JP2008274236A - Lubricating oil composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lubricating oil composition which can combine the viscosity-temperature characteristics and the low-temperature viscosity characteristics at a high level, and which keeps a satisfactory low frictional property, namely, fuel consumption saving, even at the time of the deterioration of such a lubricating oil as that due to the contamination with soot or metal wear powder, and is excellent in the durability such as the wear proofness and cleanability and in the oxidative stability and also makes possible the low ashing, and also which is capable of satisfactorily maintaining the performance of a waste-gas after-treatment device over a long period. <P>SOLUTION: The lubricating oil composition comprises a base oil of a lubricating oil having a urea-adduct value of 4% by mass or less and a viscosity index of 100 or more, and on the basis of the total amount of the composition, 0.01-10% by mass of an ashless friction adjuster, and 0.01-0.2% by mass, in terms of a phosphorus quantity, of a phosphorus-containing wear-proofing agent. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a lubricating oil composition.

  Conventionally, in the field of lubricating oil, improvement of low temperature viscosity characteristics of lubricating oil has been achieved by blending additives such as pour point depressant with lubricating base oil such as highly refined mineral oil (for example, patents) Reference 1 to 3). Further, as a method for producing a high viscosity index base oil, a method of refining a lubricating base oil by hydrocracking / hydroisomerization is known for a raw material oil containing natural or synthetic normal paraffin (for example, (See Patent Documents 4 to 6).

  As an evaluation index of the low temperature viscosity characteristics of the lubricating base oil and lubricating oil, a pour point, a cloud point, a freezing point, and the like are common. In addition, a technique for evaluating low-temperature viscosity characteristics based on a lubricating base oil such as the content of normal paraffin or isoparaffin is also known.

  By the way, in general, an internal combustion engine, an automatic transmission, a shock absorber, a drive system device such as a power steering, a gear, and the like, which are engines having sliding parts, use lubricating oil for smooth operation. Yes. In particular, lubricating oils for internal combustion engines mainly lubricate parts such as piston rings and cylinder liners, bearings for crankshafts and connecting rods, valve mechanisms, etc., as well as cooling inside the engine, cleansing and dispersing combustion products, It acts to prevent corrosion.

  As described above, in addition to low temperature viscosity characteristics, the lubricating oil for internal combustion engines is required to have various performances, and in recent years, low ash for improved fuel economy and compatibility with exhaust gas aftertreatment devices, There is also a need to achieve a high level of trade-off performance such as low phosphorus, low sulfur, and improved long drain performance. In an internal combustion engine, energy loss is large in the friction part where the lubricating oil is involved, and as a countermeasure for reducing friction loss and fuel consumption, for example, as shown in Patent Document 7, various additives such as a friction reducer are added. Lubricating oil in combination with agents is used.

  Conventionally, in order to lower the friction coefficient of lubricating oil, addition of an organic molybdenum compound typified by molybdenum dithiocarbamate or molybdenum dithiophosphate, a combination formulation of the organic molybdenum compound and a metallic detergent (see, for example, Patent Document 8), Or the combination mixing (for example, refer patent document 9) etc. of this organic molybdenum compound and a sulfur type compound are performed.

  However, in a diesel engine or a direct injection type gasoline engine, a large amount of soot generated in the piston is mixed into the engine oil. Since this soot has surface activity, it exhibits the action of adsorbing the polar additive in the oil and scraping the coating formed on the friction surface. Therefore, even under such severe friction conditions, even if an organic molybdenum compound, which is said to have the best friction reduction effect, is used, a sufficient friction reduction effect is obtained due to inhibition by soot and metal wear powder. I can't. There are few research examples to improve this, and only a few proposals have been made such as blending alkali metal borate hydrate to improve fuel efficiency of diesel engines (for example, see Patent Document 10). .

  On the other hand, it is known that lowering the viscosity of a lubricating oil is also effective as a means of improving fuel efficiency. A multi-component which is obtained by adding a viscosity index improver such as polymethacrylate or ethylene-propylene copolymer to a low-viscosity lubricating oil. Grade diesel engine oil is commonly used. However, the fuel efficiency reduction effect of the multi-grade diesel engine oil to which only these viscosity index improvers are added is insignificant, and cannot be said to be sufficient. For this reason, there has been a strong demand for the development of engine oil technology capable of exhibiting a sufficient fuel consumption reduction effect even in diesel engines and direct injection gasoline engines.

  By the way, for diesel engines, there is an urgent need to reduce NOx and particulate matter (SPM). In order to reduce these exhaust gases, for example, high pressure injection, exhaust gas recirculation system (EGR), oxidation catalyst, diesel The introduction of exhaust gas reduction means such as a particulate filter (DPF) or NOx storage reduction catalyst is being studied.

  However, it is known that, among the exhaust gas reduction means, in particular, the oxidation catalyst, NOx storage reduction catalyst, and DPF of the exhaust gas after-treatment device have a longer life depending on the composition of the engine oil used. For example, when a lubricating oil containing a zinc dialkyldithiophosphate (hereinafter referred to as ZnDTP) that is effective as an antiwear or antioxidant (peroxide decomposer) is used, the zinc content in ZnDTP is lost during the combustion process. By forming oxides, phosphates or sulfates and depositing them on the catalyst surface or in the filter, the purification performance of these exhaust gas aftertreatment devices may be impaired. Therefore, it is desirable not to add ZnDTP to the engine lubricating oil equipped with the exhaust gas aftertreatment device as described above, or to keep the amount added even if it is used. Moreover, since it is easy to produce the above-mentioned problem about a metal type detergent and a sulfur content, when a metal oxide and a sulfate deposit as ash content, it is desirable to reduce these content as much as possible.

  In addition, in diesel engines, particularly diesel engines equipped with EGR, soot is mixed in a large amount of lubricating oil, so there is a concern about increased wear of valve systems and deterioration of high temperature cleanliness such as piston cleanliness. The Further, even in a direct-injection gasoline engine, there are concerns about the same adverse effects due to soot mixing, combustion chamber deposits and valve deposits. Therefore, simply reducing the content of ZnDTP, metallic detergents, and sulfur is accompanied by a particular difficulty, and new means for compensating for the reduction in cleanliness and wear prevention associated with the reduction have been studied. I need it.

As a lubricating oil composition for an engine equipped with an exhaust gas aftertreatment device, a diesel engine oil composition having a sulfated ash content of 0.7% by mass or less has been proposed (see Patent Document 11). Further, engine oils containing a dispersion type viscosity index improver have been proposed as a means for improving cleanliness at the time of soot mixing and wear prevention (see Patent Documents 12 and 13). However, in these proposals, high-temperature cleanliness and base number maintenance performance when metal-based detergents are reduced are not always sufficient, and high-temperature cleanliness when ZnDTP content is reduced and wear prevention under mixing of soot Sex has not been fully examined. Therefore, there is room for further study in order to maintain or improve the high temperature cleanliness and base number maintainability at a high level and to suppress wear at the time of mixing soot that becomes noticeable when the blending amount of ZnDTP is reduced.
JP-A-4-36391 Japanese Patent Laid-Open No. 4-68082 Japanese Patent Laid-Open No. 4-120193 JP 2005-154760 A JP-T-2006-502298 JP-T-2002-503754 Japanese Patent Publication No. 3-23595 Japanese Examined Patent Publication No. 6-62983 Japanese Patent Publication No. 5-83599 Japanese Examined Patent Publication No. 1-48319 JP 2000-256690 A JP 2001-279287 A JP 2004-10799 A

  Recently, demands for improving the low-temperature viscosity characteristics of lubricating oils, and also for satisfying both low-temperature viscosity characteristics and viscosity-temperature characteristics are increasing, and based on the above conventional evaluation index, it is judged that low-temperature performance is good. Even when a lubricating base oil is used, it is difficult to sufficiently satisfy the required characteristics.

  Although this characteristic can be improved to some extent by blending additives into the lubricating base oil, this method has its limitations. In particular, the effect of the pour point depressant is not proportional to the concentration even if the blending amount is increased, and the shear stability is lowered as the blending amount is increased.

  Further, in the above-described method for refining a lubricating base oil by hydrocracking / hydroisomerization, the low temperature viscosity characteristics are improved by improving the isomerization ratio of normal paraffin to isoparaffin and reducing the viscosity of the lubricating base oil. From the point of view, optimization of hydrocracking / hydroisomerization conditions has been studied, but the viscosity-temperature characteristics (particularly viscosity characteristics at high temperature) and the low-temperature viscosity characteristics are in a contradictory relationship. It is very difficult to achieve both. For example, when the isomerization ratio of normal paraffin to isoparaffin is increased, the low-temperature viscosity characteristic is improved, but the viscosity-temperature characteristic becomes insufficient, for example, the viscosity index is lowered. Furthermore, as described above, it is difficult to optimize the hydrocracking / hydroisomerization conditions because the indices such as the pour point and the freezing point are not necessarily appropriate as the evaluation index of the low temperature viscosity characteristics of the lubricating base oil. It is a cause of being.

  The present invention has been made in view of such circumstances, and can achieve both a viscosity-temperature characteristic and a low-temperature viscosity characteristic at a high level, and soot and metal wear powder are mixed therein. Sufficiently low friction, that is, fuel saving, is maintained even when the lubricant is deteriorated, and it has excellent durability such as wear prevention and cleanliness, oxidation stability, and low ashing. An object of the present invention is to provide a lubricating oil composition capable of sufficiently maintaining the performance of a treatment apparatus over a long period of time.

  In order to solve the above problems, the present invention provides a lubricant base oil having a urea adduct value of 4% by mass or less and a viscosity index of 100 or more, and 0.01 to 10% by mass based on the total amount of the composition. An ashless friction modifier and a phosphorus-containing wear inhibitor having a phosphorus content of 0.01 to 0.2% by mass are provided.

  The urea adduct value as used in the present invention is measured by the following method. 100 g of weighed sample oil (lubricating base oil) is placed in a round bottom flask, 200 g of urea, 360 ml of toluene and 40 ml of methanol are added and stirred at room temperature for 6 hours. As a result, white granular crystals are produced as urea adducts in the reaction solution. The reaction solution is filtered through a 1 micron filter to collect the produced white granular crystals, and the obtained crystals are washed 6 times with 50 ml of toluene. The recovered white crystals are put in a flask, 300 ml of pure water and 300 ml of toluene are added, and the mixture is stirred at 80 ° C. for 1 hour. The aqueous phase is separated and removed with a separatory funnel, and the toluene phase is washed three times with 300 ml of pure water. A desiccant (sodium sulfate) is added to the toluene phase for dehydration, and then toluene is distilled off. The ratio (mass percentage) of the urea adduct thus obtained to the sample oil is defined as the urea adduct value.

  Moreover, the viscosity index as used in the present invention and the kinematic viscosity at 40 ° C. or 100 ° C. described later mean a viscosity index measured according to JIS K 2283-1993 and a kinematic viscosity at 40 ° C. or 100 ° C., respectively. .

  According to the lubricating base oil composition of the present invention, the urea adduct value and the viscosity index satisfy the above-mentioned conditions, respectively, and the ashless friction modifier and the phosphorus-containing antiwear agent are within the above specific ranges, respectively. In a low temperature condition of 0 ° C. or less from the practical temperature range, the viscosity resistance and stirring resistance can be greatly reduced, and the effect can be exhibited. Even when the lubricating base oil is applied to an internal combustion engine such as a direct injection gasoline engine, it is very useful in that energy loss can be reduced and energy saving can be achieved.

  In addition, as described above, improvement of the isomerization rate from normal paraffin to isoparaffin has been studied in the conventional refining method of lubricating base oil by hydrocracking / hydroisomerization. According to the above study, it is difficult to sufficiently improve the low-temperature viscosity characteristics simply by reducing the residual amount of normal paraffin. That is, the isoparaffin produced by hydrocracking / hydroisomerization contains components that adversely affect the low-temperature viscosity characteristics, but this point is not fully recognized in conventional evaluation methods. Analytical techniques such as gas chromatography (GC) and NMR are applied to the analysis of normal paraffin and isoparaffin. In these analytical techniques, components that adversely affect the low-temperature viscosity characteristics are separated or specified from isoparaffin. This cannot be said to be practically effective because it requires complicated work and a lot of time.

  On the other hand, in the measurement of the urea adduct value in the present invention, as urea adduct, a component that adversely affects low-temperature viscosity characteristics among isoparaffins, and further when normal paraffin remains in the lubricating base oil Since the normal paraffin can be collected accurately and reliably, it is excellent as an evaluation index for the low temperature viscosity characteristics of the lubricating base oil. The inventors of the present invention have analyzed by using GC and NMR that the main component of the urea adduct is a normal paraffin and an isoparaffin urea adduct having 6 or more carbon atoms from the end of the main chain to the branch position. Confirm that there is.

  In the present invention, the lubricating base oil is hydrocracked so that the raw material oil containing normal paraffin has a urea adduct value of 4% by mass or less and a viscosity index of 100 or more. / It is preferable that it is manufactured by the manufacturing method provided with the process of performing hydroisomerization.

The kinematic viscosity at 100 ° C. of the lubricating base oil is preferably 3.5 mm ² / s or higher, and the CCS viscosity at −35 ° C. of the lubricating base oil is preferably 2000 mPa · s or lower.

  The NOACK evaporation amount of the lubricating base oil is preferably 15% by mass or less.

The product of the kinematic viscosity (unit: mm ² / s) at 40 ° C. and the NOACK evaporation (unit: mass%) of the lubricating base oil is preferably 250 or less.

  The ashless friction modifier is preferably a compound containing at least 3 atoms of one or more elements selected from nitrogen, oxygen, and sulfur.

  In addition, the lubricating oil composition of the present invention preferably contains an organic molybdenum compound other than molybdenum dithiocarbamate and molybdenum dithiophosphate in an amount of 0.001 to 0.2% by mass based on the total amount of the composition.

  The use of the lubricating oil composition of the present invention is not particularly limited, but can exhibit particularly excellent effects when used as a lubricating oil for diesel engines or direct injection gasoline engines.

  According to the present invention, the viscosity-temperature characteristic and the low-temperature viscosity characteristic can be achieved at a high level, and the friction is sufficiently low even when the lubricating oil is deteriorated such that soot and metal wear powder are mixed. Maintain the performance of exhaust gas after-treatment device for a long period of time, maintaining durability, fuel economy, durability such as wear prevention and cleanliness, excellent oxidation stability, and low ashing A lubricating oil composition is provided.

  Hereinafter, preferred embodiments of the present invention will be described in detail.

  The lubricating oil composition of the present invention contains a lubricating base oil having a urea adduct value of 4% by mass and a viscosity index of 100 or more (hereinafter referred to as “the lubricating base oil according to the present invention”). .

  Further, the urea adduct value of the lubricating base oil according to the present invention is required to be 4% by mass or less as described above from the viewpoint of improving the low temperature viscosity characteristics without impairing the viscosity-temperature characteristics, preferably It is 3.5% by mass or less, more preferably 3% by mass or less, and further preferably 2.5% by mass or less. Further, the urea adduct value of the lubricating base oil may be 0% by mass.

  The viscosity index of the lubricating base oil according to the present invention needs to be 100 or more as described above from the viewpoint of viscosity-temperature characteristics, preferably 110 or more, more preferably 120 or more, still more preferably 130 or more. Especially preferably, it is 140 or more.

  When producing the lubricating base oil according to the present invention, a normal oil containing normal paraffin or a wax containing normal paraffin can be used. The raw material oil may be either mineral oil or synthetic oil, or may be a mixture of two or more of these. Further, the content of normal paraffin in the raw material oil is preferably 50% by mass or more, more preferably 70% by mass or more, still more preferably 80% by mass or more, more preferably 90% by mass, based on the total amount of the raw material oil. Especially preferably, it is 95 mass% or more, Most preferably, it is 97 mass% or more.

  Moreover, it is preferable that the raw material oil used by this invention is a wax containing raw material which boils in the lubricating oil range prescribed | regulated to ASTM D86 or ASTM D2887. The wax content of the raw material oil is preferably 50% by mass or more and 100% by mass or less based on the total amount of the raw material oil. The wax content of the raw material can be measured by analytical techniques such as nuclear magnetic resonance spectroscopy (ASTM D5292), correlated ring analysis (ndM) method (ASTM D3238), solvent method (ASTM D3235) and the like.

  Examples of the wax-containing raw material include oils derived from solvent refining methods such as raffinate, partial solvent dewaxed oil, dewaxed oil, distillate, reduced pressure gas oil, coker gas oil, slack wax, foots oil, and fisher Examples include Tropsch wax, and among these, slack wax and Fischer-Tropsch wax are preferable.

  Slack waxes are typically derived from hydrocarbon feedstocks by solvent or propane dewaxing. Slack wax may contain residual oil, which can be removed by deoiling. Foots oil corresponds to deoiled slack wax.

  Fischer-Tropsch wax is produced by a so-called Fischer-Tropsch synthesis method.

  Furthermore, you may use a commercial item as raw material oil containing normal paraffin. Specific examples include Paraflint 80 (hydrogenated Fischer-Tropsch wax) and Shell MDS Waxy Raffinate (hydrogenated and partially isomerized middle distillate synthetic waxy raffinate). It is done.

  Moreover, the raw material oil derived from solvent extraction is obtained by sending a high-boiling petroleum fraction from atmospheric distillation to a vacuum distillation apparatus and solvent-extracting the distillation fraction from this apparatus. The residue from the vacuum distillation may be denitrified. In the solvent extraction method, aromatic components are dissolved in the extraction phase while leaving more paraffinic components in the raffinate phase. Naphthene is partitioned into the extraction phase and the raffinate phase. As the solvent for solvent extraction, phenol, furfural, N-methylpyrrolidone and the like are preferably used. By controlling the solvent / oil ratio, the extraction temperature, the method of contacting the distillate to be extracted with the solvent, etc., the degree of separation between the extraction phase and the raffinate phase can be controlled. Furthermore, a bottom fraction obtained from a fuel oil hydrocracking apparatus may be used as a raw material by using a fuel oil hydrocracking apparatus having higher hydrogenation resolution.

The raw material oil is subjected to hydrocracking / hydroisomerization so that the urea adduct value of the material to be treated is 4% by mass or less and the viscosity index is 100 or more. Such a lubricating base oil can be obtained. The hydrocracking / hydroisomerization step is not particularly limited as long as the urea adduct value and the viscosity index of the obtained workpiece satisfy the above conditions. The preferred hydrocracking / hydroisomerization step in the present invention is:
A first step of hydrotreating a raw oil containing normal paraffin using a hydrotreating catalyst;
A second step of hydrodewaxing the object to be treated obtained in the first step using a hydrodewaxing catalyst;
The to-be-processed object obtained by a 2nd process is equipped with the 3rd process of hydrotreating using a hydrotreating catalyst.

  In the conventional hydrocracking / hydroisomerization, a hydrotreating step is provided before the hydrodewaxing step for the purpose of desulfurization / denitrogenation for the prevention of poisoning of the hydrodewaxing catalyst. There is a thing. On the other hand, in the first step (hydrotreating step) in the present invention, a part of the normal paraffin in the feedstock (for example, about 10% by mass, preferably in the previous stage of the second step (hydrodewaxing step), preferably 1 to 10% by mass), and desulfurization / denitrogenation is possible in the first step, but the purpose is different from that of the conventional hydrotreatment. Providing such a first step is preferable for ensuring that the urea adduct value of the article to be processed (lubricant base oil) obtained after the third step is 4% by mass or less.

  Examples of the hydrogenation catalyst used in the first step include a catalyst containing a Group 6 metal, a Group 8-10 metal, and a mixture thereof. Preferred metals include nickel, tungsten, molybdenum, cobalt, and mixtures thereof. The hydrogenation catalyst can be used in a form in which these metals are supported on a refractory metal oxide support, and the metal is usually present as an oxide or sulfide on the support. When a metal mixture is used, the metal may be present as a bulk metal catalyst in which the amount of metal is 30% by mass or more based on the total amount of the catalyst. Examples of the metal oxide support include oxides such as silica, alumina, silica-alumina, and titania, and among these, alumina is preferable. Preferred alumina is γ-type or β-type porous alumina. The amount of metal supported is preferably in the range of 0.5 to 35% by mass based on the total amount of the catalyst. Also, when using a mixture of Group 9-10 metal and Group 6 metal, either Group 9 or Group 10 metal is present in an amount of 0.1-5% by weight, based on the total amount of catalyst, The Group 6 metal is preferably present in an amount of 5 to 30% by mass. Metal loading may be measured by atomic absorption spectroscopy, inductively coupled plasma emission spectroscopy, or other methods specified by ASTM for individual metals.

  The acidity of the metal oxide support can be controlled by adding additives, controlling the nature of the metal oxide support (eg, controlling the amount of silica incorporated into the silica-alumina support), and the like. Examples of additives include halogens, especially fluorine, phosphorus, boron, yttria, alkali metals, alkaline earth metals, rare earth oxides, and magnesia. Cocatalysts such as halogen generally increase the acidity of the metal oxide support, but weakly basic additives such as yttria or magnesia tend to weaken the acidity of such support.

Regarding the hydrotreatment conditions, the treatment temperature is preferably 150 to 450 ° C., more preferably 200 to 400 ° C., the hydrogen partial pressure is preferably 1400 to 20000 kPa, more preferably 2800 to 14000 kPa, and the liquid space velocity (LHSV) is preferably 0.1 to 10 ^-1, more preferably 0.1～5Hr ^-1, a hydrogen / oil ratio is preferably 50~1780m ³ / ^{m 3,} more preferably 89～890M ³ / M ³ . In addition, said conditions are an example and the hydrotreating conditions in the 1st process for the urea adduct value and viscosity index of the to-be-processed object obtained after a 3rd process satisfy | fill the said conditions respectively are a raw material, a catalyst, an apparatus, etc. It is preferable to select appropriately according to the difference.

  The object to be processed after the hydrogenation treatment in the first step may be used as it is in the second step, but the object to be processed is stripped or distilled to generate gas from the object to be processed (liquid product). It is preferable to provide a step of separating and removing the object between the first step and the second step. Thereby, the nitrogen content and sulfur content contained in the object to be treated can be reduced to a level without affecting the long-term use of the hydrodewaxing catalyst in the second step. The object of separation and removal by stripping or the like is mainly gaseous foreign matters such as hydrogen sulfide and ammonia, and stripping can be performed by ordinary means such as a flash drum and a fractionator.

  Moreover, when the conditions of the hydrogenation treatment in the first step are mild, there is a possibility that the remaining polycyclic aromatics may pass through depending on the raw materials used. It may be removed by purification.

  Further, the hydrodewaxing catalyst used in the second step may contain either crystalline or amorphous material. Examples of the crystalline material include molecular sieves having a 10- or 12-membered ring passage mainly composed of aluminosilicate (zeolite) or silicoaluminophosphate (SAPO). Specific examples of zeolite include ZSM-22, ZSM-23, ZSM-35, ZSM-48, ZSM-57, ferrierite, ITQ-13, MCM-68, MCM-71 and the like. Moreover, ECR-42 is mentioned as an example of an aluminophosphate. Examples of molecular sieves include zeolite beta and MCM-68. Among these, it is preferable to use 1 type, or 2 or more types selected from ZSM-48, ZSM-22, and ZSM-23, and ZSM-48 is particularly preferable. The molecular sieve is preferably in the hydrogen form. Although the reduction of the hydrodewaxing catalyst can occur in situ at the time of hydrodewaxing, a hydrodewaxing catalyst that has been subjected to a reduction treatment in advance may be subjected to hydrodewaxing.

  Examples of the amorphous material of the hydrodewaxing catalyst include alumina doped with a group 3 metal, fluorided alumina, silica-alumina, fluorided silica-alumina, silica-alumina, and the like.

  Preferred embodiments of the dewaxing catalyst include those equipped with bifunctional, ie, metal hydrogenation components that are at least one Group 6 metal, at least one Group 8-10 metal, or mixtures thereof. Preferred metals are group 9-10 noble metals such as Pt, Pd or mixtures thereof. The mounting amount of these metals is preferably 0.1 to 30% by mass based on the total amount of the catalyst. Examples of the catalyst preparation and the metal mounting method include an ion exchange method and an impregnation method using a decomposable metal salt.

  When molecular sieves are used, they may be combined with a binder material having heat resistance under hydrodewaxing conditions, or may be without a binder (self-bonding). As binder materials, silica, alumina, silica-alumina, combinations of two components of silica and other metal oxides such as titania, magnesia, tria, zirconia, silica-alumina-tria, silica-alumina-magnesia, etc. Inorganic oxides such as a combination of three components of oxides such as The amount of the molecular sieve in the hydrodewaxing catalyst is preferably 10 to 100% by mass, more preferably 35 to 100% by mass, based on the total amount of the catalyst. The hydrodewaxing catalyst is formed by a method such as spray drying or extrusion. The hydrodewaxing catalyst can be used in a sulfided or non-sulfided form, and a sulfided form is preferred.

Regarding hydrodewaxing conditions, the temperature is preferably 250-400 ° C., more preferably 275-350 ° C., and the hydrogen partial pressure is preferably 791-20786 kPa (100-3000 psig), more preferably 1480-17339 kPa (200- a 2500 psig), liquid hourly space velocity is preferably 0.1 to 10 ^-1, more preferably 0.1~5hr ^-1, a hydrogen / oil ratio is preferably 45~1780m ³ / ^{m 3} (250~10000scf / B), more preferably ^{89~890m 3 / m 3 (500~5000scf /} B). In addition, said conditions are an example and the hydrodewaxing conditions in the 2nd process for the urea adduct value and viscosity index of the to-be-processed object obtained after a 3rd process satisfy | fill the said conditions are a raw material, a catalyst, and an apparatus, respectively. It is preferable to select appropriately according to the difference.

  The object to be treated that has been hydrodewaxed in the second step is subjected to hydrorefining in the third step. Hydrorefining is a form of mild hydrotreating that aims to saturate olefins and residual aromatic compounds by hydrogenation in addition to removal of residual heteroatoms and hues. The hydrorefining in the third step can be carried out in cascade with the dewaxing step.

  The hydrorefining catalyst used in the third step is preferably a metal oxide carrier on which a Group 6 metal, a Group 8-10 metal or a mixture thereof is supported. Preferred metals include noble metals, especially platinum, palladium and mixtures thereof. If a mixture of metals is used, it may be present as a bulk metal catalyst where the amount of metal is 30% by weight or more based on the catalyst. The metal content of the catalyst is preferably 20% by mass or less for non-noble metals and 1% by mass or less for noble metals. The metal oxide support may be either amorphous or crystalline oxide. Specific examples include low acid oxides such as silica, alumina, silica-alumina or titania, and alumina is preferred. From the viewpoint of saturation of the aromatic compound, it is preferable to use a hydrorefining catalyst in which a metal having a relatively strong hydrogenation function is supported on a porous support.

  Preferred hydrorefining catalysts include mesoporous materials belonging to the M41S class or family of catalysts. M41S series catalysts are mesoporous materials with high silica content, and specifically include MCM-41, MCM-48 and MCM-50. Such a hydrorefining catalyst has a pore diameter of 15 to 100 mm, and MCM-41 is particularly preferable. MCM-41 is an inorganic porous non-layered phase having a hexagonal arrangement of uniformly sized pores. The physical structure of MCM-41 is like a bundle of straws where the opening of the straw (cell diameter of the pores) is in the range of 15-100 angstroms. MCM-48 has cubic symmetry, and MCM-50 has a layered structure. MCM-41 can be manufactured with pore openings of different sizes in the mesoporous range. The mesoporous material may have a metal hydrogenation component that is at least one of a Group 8, 9 or 10 metal, and the metal hydrogenation component is preferably a noble metal, particularly a Group 10 noble metal, Pt , Pd or mixtures thereof are most preferred.

Regarding the hydrorefining conditions, the temperature is preferably 150-350 ° C, more preferably 180-250 ° C, the total pressure is preferably 2859-20786 kPa (about 400-3000 psig), and the liquid space velocity is preferably 0. 0.1 to 5 hr ⁻¹ , more preferably 0.5 to ³ hr ⁻¹ , and the hydrogen / oil ratio is preferably 44.5 to 1780 m ³ / m ³ (250 to 10,000 scf / B). In addition, said conditions are an example and the hydrogenation production | generation conditions in the 3rd process for the urea adduct value and viscosity index of the to-be-processed object obtained after a 3rd process satisfy | fill the said conditions respectively are the difference of a raw material or a processing apparatus. It is preferable to select appropriately according to.

  Moreover, about the to-be-processed object obtained after a 3rd process, you may separate and remove a predetermined component by distillation etc. as needed.

  In the lubricating base oil according to the present invention obtained by the above production method, the other properties are not particularly limited as long as the urea adduct value and the viscosity index satisfy the above conditions, respectively, but the lubricating base oil according to the present invention is It is preferable that the following conditions are further satisfied.

  The content of the saturated component in the lubricating base oil according to the present invention is preferably 90% by mass or more, more preferably 93% by mass or more, and still more preferably 95% by mass or more, based on the total amount of the lubricating oil base oil. Moreover, the ratio of the cyclic | annular saturated part to the said saturated part becomes like this. Preferably it is 0.1-50 mass%, More preferably, it is 0.5-40 mass%, More preferably, it is 1-30 mass%, Most preferably, it is 5-20. % By mass. Viscosity-temperature characteristics and thermal / oxidative stability can be achieved by satisfying the above conditions for the content of the saturated component and the ratio of the cyclic saturated component in the saturated component, respectively. When the additive is blended, the function of the additive can be expressed at a higher level while the additive is sufficiently stably dissolved and held in the lubricating base oil. Furthermore, when the content of the saturated component and the ratio of the cyclic saturated component in the saturated component satisfy the above conditions, the friction characteristics of the lubricating base oil itself can be improved, and as a result, the friction reducing effect is improved. As a result, energy saving can be improved.

  In addition, when content of a saturated part is less than 90 mass%, it exists in the tendency for a viscosity-temperature characteristic, thermal / oxidation stability, and a friction characteristic to become inadequate. Further, when the ratio of the cyclic saturated component to the saturated component is less than 0.1% by mass, when the additive is blended with the lubricating base oil, the solubility of the additive becomes insufficient, and the lubricating base Since the effective amount of the additive dissolved and retained in the oil is reduced, the function of the additive tends to be unable to be obtained effectively. Furthermore, when the ratio of the cyclic saturated component in the saturated component exceeds 50% by mass, the effectiveness of the additive tends to decrease when the additive is blended with the lubricating base oil.

  In the present invention, the ratio of the cyclic saturated component in the saturated component being 0.1 to 50% by mass is equivalent to the non-cyclic saturated component in the saturated component being 99.9 to 50% by mass. Here, the non-cyclic saturated component includes both normal paraffin and isoparaffin. The proportion of normal paraffin and isoparaffin in the lubricating base oil according to the present invention is not particularly limited as long as the urea adduct value satisfies the above conditions, but the proportion of isoparaffin is preferably 50 to 99 based on the total amount of the lubricating base oil. 9.9% by mass, more preferably 60 to 99.9% by mass, still more preferably 70 to 99% by mass, and particularly preferably 80 to 99.9% by mass. When the ratio of isoparaffin in the lubricating base oil satisfies the above conditions, the viscosity-temperature characteristics and thermal / oxidative stability can be further improved, and when the additive is added to the lubricating base oil Therefore, the function of the additive can be expressed at a higher level while the additive is sufficiently stably dissolved and held.

  In addition, content of the saturated part said by this invention means the value (unit: mass%) measured based on ASTM D 2007-93.

  Moreover, the ratio of the cyclic saturated component and the non-cyclic saturated component in the saturated component referred to in the present invention is a naphthene component measured according to ASTM D 2786-91, respectively (measuring object: 1-ring to 6-ring naphthene, unit : Mass%) and alkane content (unit: mass%).

In addition, the ratio of normal paraffin in the lubricating base oil referred to in the present invention is a gas chromatographic analysis of the saturated component separated and fractionated by the method described in ASTM D 2007-93 under the following conditions. This means a value obtained by converting the measured value when the ratio of normal paraffin in the saturated content is identified and quantified, based on the total amount of the lubricating base oil. In the identification and quantification, a normal paraffin mixed sample having 5 to 50 carbon atoms is used as a standard sample, and the normal paraffin occupying the saturated component is the total peak area value of the chromatogram (the peak derived from the diluent). Is obtained as a ratio of the sum of peak area values corresponding to each normal paraffin.
(Gas chromatography conditions)
Column: non-polar liquid phase column (length 25 mm, inner diameter 0.3 mmφ, liquid phase film thickness 0.1 μm)
Temperature rising condition: 50 ° C. to 400 ° C. (temperature rising rate: 10 ° C./min)
Carrier gas: helium (linear velocity: 40 cm / min)
Split ratio: 90/1
Sample injection amount: 0.5 μL (injection amount of sample diluted 20 times with carbon disulfide)

  Further, the ratio of isoparaffin in the lubricating base oil means a value obtained by converting the difference between the non-cyclic saturated component in the saturated component and the normal paraffin component in the saturated component, based on the total amount of the lubricant base oil. .

  In the method of separating saturated components, or in analyzing the composition of cyclic saturated components, non-cyclic saturated components, etc., a similar method can be used in which similar results can be obtained. For example, in addition to the above, a method described in ASTM D 2425-93, a method described in ASTM D 2549-91, a method using high performance liquid chromatography (HPLC), a method obtained by improving these methods, and the like can be given.

  In the lubricating base oil according to the present invention, when the bottom fraction obtained from the fuel oil hydrocracking apparatus is used as a raw material, the content of the saturated component is 90% by mass or more and occupies the saturated component. The proportion of cyclic saturated component is 30 to 50% by mass, the proportion of non-cyclic saturated component in the saturated component is 50 to 70% by mass, the proportion of isoparaffin in the lubricating base oil is 40 to 70% by mass, and the viscosity index is Although a base oil of 100 to 135, preferably 120 to 130 is obtained, the urea adduct value satisfies the above conditions, the effect of the present invention, the improvement of low temperature viscosity characteristics and the wear prevention property and low friction property when soot is mixed. Can be achieved, and in particular, it is possible to obtain an effect that a significant improvement in low-temperature viscosity characteristics can be realized. In the lubricating base oil according to the present invention, when slack wax or Fischer-Tropsch wax, which is a raw material having a high wax content (for example, a normal paraffin content of 50% by mass or more) is used as a raw material, Of 90% by mass or more, the proportion of cyclic saturated component in the saturated component is 0.1 to 40% by mass, the proportion of non-cyclic saturated component in the saturated component is 60 to 99.9% by mass, lubrication A base oil having a ratio of isoparaffin in the oil base oil of 60 to 99.9% by mass and a viscosity index of 100 to 170, preferably 135 to 160 is obtained. The composition of the lubricating oil that has both the effects of high-viscosity, improved low-temperature viscosity characteristics, anti-wear and low-friction properties at the time of soot mixing, and has particularly excellent high viscosity index and low-temperature viscosity characteristics It is possible to obtain.

Further, when the refractive index at 20 ° C. is represented by n ₂₀ and the kinematic viscosity at 100 ° C. is represented by kv100, n ₂₀ −0.002 × kv100 for the lubricating base oil according to the present invention is preferably 1.435 to 1. 450, more preferably 1.440 to 1.449, still more preferably 1.442 to 1.448, and still more preferably 1.444 to 1.447. _By setting n ₂₀ −0.002 × kv100 within the above range, excellent viscosity-temperature characteristics and thermal / oxidative stability can be achieved, and an additive is blended in the lubricating base oil. In this case, the function of the additive can be expressed at a higher level while the additive is sufficiently stably dissolved and held in the lubricating base oil. Furthermore, by setting n ₂₀ −0.002 × kv100 within the above range, the friction characteristics of the lubricating base oil itself can be improved, and as a result, an improvement in friction reduction effect and an improvement in energy saving can be achieved. can do.

When n ₂₀ −0.002 × kv100 exceeds the upper limit, the viscosity-temperature characteristics, thermal / oxidation stability, and friction characteristics become insufficient, and further, an additive is blended in the lubricating base oil. In some cases, the effectiveness of the additive tends to decrease. Further, when n ₂₀ −0.002 × kv100 is less than the lower limit, when an additive is blended in the lubricating base oil, the solubility of the additive becomes insufficient, and the lubricating base oil contains Since the effective amount of the additive that is dissolved and held is lowered, the function of the additive tends to be unable to be obtained effectively.

In addition, the refractive index (n20) in ₂₀ degreeC said by this invention means the refractive index measured in 20 degreeC based on ASTMD1218-92. The kinematic viscosity (kv100) at 100 ° C. in the present invention means a kinematic viscosity measured at 100 ° C. in accordance with JIS K 2283-1993.

  The aromatic content in the lubricating base oil according to the present invention is preferably 5% by mass or less, more preferably 0.05 to 3% by mass, and still more preferably 0.1 to 3% by mass, based on the total amount of the lubricating base oil. 1% by mass, particularly preferably 0.1 to 0.5% by mass. If the aromatic content exceeds the above upper limit, the viscosity-temperature characteristics, thermal / oxidative stability, friction characteristics, volatilization prevention characteristics and low-temperature viscosity characteristics tend to decrease. When an additive is blended with the additive, the effectiveness of the additive tends to decrease. Further, the lubricating base oil according to the present invention may not contain an aromatic component, but the solubility of the additive is further improved by setting the aromatic content to 0.05% by mass or more. Can be increased.

  In addition, content of an aromatic content here means the value measured based on ASTM D 2007-93. In general, the aromatic component includes alkylbenzene, alkylnaphthalene, anthracene, phenanthrene, and alkylated products thereof, as well as compounds in which four or more benzene rings are condensed, pyridines, quinolines, phenols, naphthols and the like. Aromatic compounds having atoms are included.

Further, the% C _p of the lubricating base oil according to the present invention is preferably 80 or more, more preferably 82 to 99, still more preferably 85 to 98, and particularly preferably 90 to 97. If the% C _p of the lubricating base oil is less than 80, the viscosity-temperature characteristics, thermal / oxidative stability, and friction characteristics tend to be reduced, and when the additive is added to the lubricating base oil The effectiveness of the additive tends to decrease. Further, when the% C _p value of the lubricating base oil exceeds 99, the additive solubility will tend to be lower.

Moreover,% _{C N} of the lubricating base oil according to the present invention is preferably 20 or less, more preferably 15 or less, more preferably 1 to 12, particularly preferably 3 to 10. If the% C _N value of the lubricating base oil exceeds 20, the viscosity - temperature characteristic, heat and oxidation stability and frictional properties will tend to be reduced. Moreover, when% _CN is less than 1, the solubility of the additive tends to decrease.

Moreover,% _{C A} of the lubricating base oil according to the present invention is preferably 0.7 or less, more preferably 0.6 or less, more preferably 0.1 to 0.5. When% C _A of the lubricating base oil exceeds 0.7, the viscosity - temperature characteristic, heat and oxidation stability and frictional properties will tend to be reduced. Moreover,% C _A of the lubricating base oil according to the present invention may be 0% by 0.1 or more C _A, it is possible to further increase the solubility of additives.

Furthermore, the ratio of the lubricating base% in oil _{C P} and% _{C N} of the present _invention,% C is preferably P /% _{C N} is 7 or more, more preferably 7.5 or more, More preferably, it is 8 or more. When% C _P /% _CN is less than 7, viscosity-temperature characteristics, thermal / oxidative stability and friction characteristics tend to be reduced, and further when an additive is blended in the lubricating base oil. The effectiveness of the additive tends to decrease. _{Moreover,% C} P /% C _N is preferably 200 or less, more preferably 100 or less, more preferably 50 or less, particularly preferably 25 or less. By setting% C _P /% _CN to 200 or less, the solubility of the additive can be further increased.

Incidentally, _say% C P in the present invention,% _C A _N and% _{C A,} obtained by a method in accordance with ASTM D 3238-85, respectively (n-d-M ring analysis), the total carbon number of the paraffin carbon number The percentage of the total number of naphthene carbons to the total number of carbons, and the percentage of the total number of aromatic carbons to the total number of carbons. That is, the preferred ranges of% C _P ,% C _N and% C _A described above are based on the values obtained by the above method. For example, even a lubricating base oil containing no naphthene is obtained by the above method. is% C _N may indicate a value greater than zero.

  The iodine value of the lubricating base oil of the present invention is preferably 0.5 or less, more preferably 0.3 or less, still more preferably 0.15 or less, and less than 0.01. However, it is preferably 0.001 or more, more preferably 0.05 or more, from the viewpoint of small effects that are commensurate with it and economic efficiency. By setting the iodine value of the lubricating base oil to 0.5 or less, the thermal and oxidation stability can be dramatically improved. In addition, the iodine value as used in the field of this invention means the iodine value measured by the indicator titration method of JIS K0070 "the acid value of a chemical product, the saponification value, the iodine value, the hydroxyl value, and the unsaponification value."

  Further, the content of sulfur in the lubricating base oil according to the present invention depends on the content of sulfur in the raw material. For example, when a raw material that does not substantially contain sulfur such as a synthetic wax component obtained by a Fischer-Tropsch reaction or the like is used, a lubricating base oil that does not substantially contain sulfur can be obtained. In addition, when using raw materials containing sulfur such as slack wax obtained in the refining process of the lubricating base oil and microwax obtained in the refining process, the sulfur content in the obtained lubricating base oil is usually 100 mass ppm. That's it. In the lubricating base oil according to the present invention, the content of sulfur is preferably 10 ppm by mass or less, and is preferably 5 ppm by mass or less, from the viewpoint of further improving thermal and oxidation stability and reducing sulfur content. More preferred is 3 ppm by mass or less.

  Further, from the viewpoint of cost reduction, it is preferable to use slack wax or the like as a raw material. In that case, the sulfur content in the obtained lubricating base oil is preferably 50 ppm by mass or less, and preferably 10 ppm by mass or less. More preferred. In addition, the sulfur content as used in the field of this invention means the sulfur content measured based on JISK2541-1996.

  The nitrogen content in the lubricating base oil according to the present invention is not particularly limited, but is preferably 5 ppm by mass or less, more preferably 3 ppm by mass or less, and further preferably 1 ppm by mass or less. If the nitrogen content exceeds 5 ppm by mass, the thermal and oxidation stability tends to decrease. In addition, the nitrogen content as used in the field of this invention means the nitrogen content measured based on JISK2609-1990.

The kinematic viscosity of the lubricating base oil according to the present invention is preferably 1.5 to ²⁰ mm ² / s, more preferably 2.0 to 11 mm ² / s at 100 ° C. When the kinematic viscosity at 100 ° C. of the lubricating base oil is less than 1.5 mm ² / s, it is not preferable in terms of evaporation loss. In addition, when trying to obtain a lubricating base oil having a kinematic viscosity at 100 ° C. exceeding 20 mm ² / s, the yield decreases, and the decomposition rate can be increased even when heavy wax is used as a raw material. Since it becomes difficult, it is not preferable.

In the present invention, it is preferable to use a lubricating base oil having a kinematic viscosity at 100 ° C. in the following range by distillation or the like.
(I) less than the kinematic viscosity at 100 ° C. is 1.5 mm ² / s or more 3.5 mm ² / s, more preferably kinematic viscosity at 2.0 to 3.0 mm ² / s lubricating base oils (II) 100 ° C. There 3.0 mm ² / s or more 4.5mm less than ² / s, more preferably a kinematic viscosity at 3.5~4.1mm ² / s lubricating base oil (III) 100 ℃ 4.5~20mm ² / s, more preferably 4.8 to 11 mm ² / s, particularly preferably 5.5 to 8.0 mm ² / s.

Moreover, the kinematic viscosity at 40 ° C. of the lubricating base oil according to the present invention is preferably 6.0 to 80 mm ² / s, more preferably 8.0 to 50 mm ² / s. In the present invention, it is preferred that a lubricating oil fraction having a kinematic viscosity at 40 ° C. in the following range is fractionated by distillation or the like and used.
(IV) less than the kinematic viscosity at 40 ° C. is 6.0 mm ² / s or more 12 mm ² / s, more preferably 8.0~12mm ² / s lubricating base oil (V) kinematic viscosity at 40 ° C. is 12 mm ² / More than s and less than 28 mm < ² > / s, more preferably 13-19 mm < ² > / s lubricating base oil (VI) The kinematic viscosity at 40 [deg.] C. is 28-50 mm < ² > / s, more preferably 29-45 mm < ² > / s, particularly preferred. Is a lubricating base oil of 30 to 40 mm ² / s.

  The above-mentioned lubricating base oils (I) and (IV) have a viscosity-temperature characteristic and low temperature compared with conventional lubricating base oils having the same viscosity grade by satisfying the above conditions for the urea adduct value and the viscosity index, respectively. Viscosity characteristics can be achieved at a high level, in particular, low temperature viscosity characteristics are excellent, and viscosity resistance and stirring resistance can be significantly reduced. Moreover, the BF viscosity in -40 degreeC can be 2000 mPa * s or less by mix | blending a pour point depressant. The BF viscosity at −40 ° C. means the viscosity measured according to JPI-5S-26-99.

  The lubricating base oils (II) and (V) have a viscosity-temperature characteristic compared to a conventional lubricating base oil having the same viscosity grade by satisfying the above conditions for the urea adduct value and the viscosity index, respectively. And low-temperature viscosity characteristics can be achieved at a high level. In particular, the low-temperature viscosity characteristics are excellent, and further, volatilization prevention and lubricity are excellent. For example, in the lubricating base oils (II) and (V), the CCS viscosity at −35 ° C. can be set to 3000 mPa · s or less.

  In addition, the lubricating base oils (III) and (VI) have viscosity-temperature characteristics compared to conventional lubricating base oils having the same viscosity grade by satisfying the above conditions for the urea adduct value and the viscosity index, respectively. And low-temperature viscosity characteristics can be achieved at a high level. In particular, the low-temperature viscosity characteristics are excellent, and further, volatilization prevention, thermal / oxidative stability, and lubricity are excellent.

  Further, the refractive index at 20 ° C. of the lubricating base oil according to the present invention depends on the viscosity grade of the lubricating base oil, and for example, the refractive index at 20 ° C. of the lubricating base oils (I) and (IV). Is preferably 1.455 or less, more preferably 1.453 or less, and still more preferably 1.451 or less. Moreover, the refractive index at 20 ° C. of the lubricating base oils (II) and (V) is preferably 1.460 or less, more preferably 1.457 or less, and still more preferably 1.455 or less. The refractive index of the lubricating base oils (III) and (VI) at 20 ° C. is preferably 1.465 or less, more preferably 1.463 or less, and still more preferably 1.460 or less. If the refractive index exceeds the above upper limit, the viscosity-temperature characteristics and thermal / oxidative stability of the lubricating base oil tend to be reduced, and further, the volatilization preventing properties and low-temperature viscosity characteristics tend to deteriorate. When an additive is blended with the additive, the effectiveness of the additive tends to decrease.

  Further, the pour point of the lubricating base oil according to the present invention depends on the viscosity grade of the lubricating base oil. For example, the pour point of the lubricating base oils (I) and (IV) is preferably −10. ° C or lower, more preferably -12.5 ° C or lower, still more preferably -15 ° C or lower. The pour points of the lubricating base oils (II) and (V) are preferably −10 ° C. or lower, more preferably −15 ° C. or lower, and still more preferably −17.5 ° C. or lower. The pour point of the lubricating base oils (III) and (VI) is preferably −10 ° C. or lower, more preferably −12.5 ° C. or lower, and still more preferably −15 ° C. or lower. When the pour point exceeds the upper limit, the low temperature fluidity of the entire lubricating oil using the lubricating base oil tends to decrease. In addition, the pour point as used in the field of this invention means the pour point measured based on JISK2269-1987.

  Further, the CCS viscosity of the lubricating base oil according to the present invention at −35 ° C. depends on the viscosity grade of the lubricating base oil, but for example, the lubricating base oils (I) and (IV) at −35 ° C. The CCS viscosity is preferably 1000 mPa · s or less. Further, the CCS viscosity at −35 ° C. of the lubricating base oils (II) and (V) is preferably 3000 mPa · s or less, more preferably 2400 mPa · s or less, still more preferably 2000 mPa · s or less, and further preferably 1800 mPa · s. · S or less, more preferably 1600 mPa · s or less, particularly preferably 1500 mPa · s or less. The CCS viscosity of the lubricating base oils (III) and (VI) at −35 ° C. is preferably 15000 mPa · s or less, more preferably 10000 mPa · s or less. When the CCS viscosity at −35 ° C. exceeds the upper limit, the low-temperature fluidity of the entire lubricating oil using the lubricating base oil tends to decrease. In addition, the CCS viscosity at −35 ° C. in the present invention means a viscosity measured according to JIS K 2010-1993.

  In addition, the BF viscosity at −40 ° C. of the lubricating base oil according to the present invention depends on the viscosity grade of the lubricating base oil, for example, at −40 ° C. of the lubricating base oils (I) and (IV). The BF viscosity is preferably 10,000 mPa · s or less, more preferably 8000 mPa · s, and still more preferably 6000 mPa · s or less. Moreover, the BF viscosity at −40 ° C. of the lubricating base oils (II) and (V) is preferably 1500,000 mPa · s or less, more preferably 1000000 mPa · s or less. When the BF viscosity at −40 ° C. exceeds the upper limit, the low-temperature fluidity of the entire lubricating oil using the lubricating base oil tends to decrease.

Further, the density (ρ ₁₅ ) at 15 ° C. of the lubricating base oil according to the present invention depends on the viscosity grade of the lubricating base oil, but is not more than the value of ρ represented by the following formula (1), that is, ρ It is preferable that ₁₅ ≦ ρ.
ρ = 0.0025 × kv100 + 0.816 (1)
[Wherein, kv100 represents the kinematic viscosity (mm ² / s) of the lubricating base oil at 100 ° C. ]

When ρ ₁₅ > ρ, the viscosity-temperature characteristics and thermal / oxidation stability, volatilization prevention properties and low-temperature viscosity characteristics tend to decrease, and additives are added to the lubricating base oil. In some cases, the effectiveness of the additive tends to decrease.

For example, ρ ₁₅ of the lubricating base oils (I) and (IV) is preferably 0.825 or less, more preferably 0.820 or less. Moreover, ρ ₁₅ of the lubricating base oils (II) and (V) is preferably 0.835 or less, more preferably 0.830 or less. The ρ ₁₅ of the lubricating base oils (III) and (VI) is preferably 0.840 or less, more preferably 0.835 or less.

  In addition, the density in 15 degreeC said by this invention means the density measured in 15 degreeC based on JISK2249-1995.

Further, the aniline point (AP (° C.)) of the lubricating base oil according to the present invention depends on the viscosity grade of the lubricating base oil, but is not less than the value of A represented by the following formula (2). It is preferable that ≧ A.
A = 4.3 × kv100 + 100 (2)
[Wherein, kv100 represents the kinematic viscosity (mm ² / s) of the lubricating base oil at 100 ° C. ]

  When AP <A, viscosity-temperature characteristics and thermal / oxidative stability, volatilization prevention properties and low-temperature viscosity characteristics tend to decrease, and when additives are added to the lubricating base oil In addition, the effectiveness of the additive tends to decrease.

  For example, the AP of the lubricating base oils (I) and (IV) is preferably 108 ° C. or higher, more preferably 110 ° C. or higher. The AP of the lubricating base oils (II) and (V) is preferably 113 ° C. or higher, more preferably 119 ° C. or higher. The AP of the lubricating base oils (III) and (VI) is preferably 125 ° C. or higher, more preferably 128 ° C. or higher. In addition, the aniline point as used in the field of this invention means the aniline point measured based on JISK2256-1985.

  Further, the NOACK evaporation amount of the lubricating base oil according to the present invention is not particularly limited. For example, the NOACK evaporation amount of the lubricating base oils (I) and (IV) is preferably 20% by mass or more, more preferably. Is 25% by mass or more, more preferably 30 or more, preferably 50% by mass or less, more preferably 45% by mass or less, and still more preferably 40% by mass or less. The NOACK evaporation amount of the lubricating base oils (II) and (V) is preferably 5% by mass or more, more preferably 8% by mass or more, still more preferably 10% by mass or more, and preferably 20%. It is at most mass%, more preferably at most 16 mass%, still more preferably at most 15 mass%. The NOACK evaporation amount of the lubricating base oils (III) and (VI) is preferably 0% by mass or more, more preferably 1% by mass or more, and preferably 6% by mass or less, more preferably 5%. It is not more than mass%, more preferably not more than 4 mass%. When the NOACK evaporation amount is the lower limit value, it tends to be difficult to improve the low temperature viscosity characteristics. Further, when the NOACK evaporation amount exceeds the upper limit value, when the lubricating base oil is used as the lubricating oil for an internal combustion engine, the evaporation loss amount of the lubricating oil increases, and accordingly, catalyst poisoning is promoted. Therefore, it is not preferable. In addition, the NOACK evaporation amount as used in the field of this invention means the evaporation loss amount measured based on ASTM D 5800-95.

  The product of the kinematic viscosity (unit: mm2 / s) and the NOACK evaporation (unit: mass%) at 40 ° C. of the lubricating base oils (II) and (V) is not particularly limited, but preferably It is 250 or less, more preferably 240 or less, further preferably 230 or less, more preferably 220 or less, particularly preferably 210 or less, and particularly preferably 200 or less. That is, unprecedented excellent lubrication in which the smaller the product of the kinematic viscosity (unit: mm2 / s) at 40 ° C. and the NOACK evaporation amount (unit: mass%), the lower the viscosity and the lower the evaporation property. Means an oil base oil.

  Further, the distillation properties of the lubricating base oil according to the present invention are preferably gas chromatography distillation, wherein the initial boiling point (IBP) is 290 to 440 ° C. and the end point (FBP) is 430 to 580 ° C. Lubricating base oils (I) to (III) and (IV) to (VI) having the preferred viscosity ranges described above are obtained by rectifying one or more fractions selected from the fractions in the range. Obtainable.

  For example, regarding the distillation properties of the lubricating base oils (I) and (IV), the initial boiling point (IBP) is preferably 260 to 340 ° C, more preferably 270 to 330 ° C, and still more preferably 280 to 320 ° C. It is. Moreover, 10% distillation temperature (T10) becomes like this. Preferably it is 310-390 degreeC, More preferably, it is 320-380 degreeC, More preferably, it is 330-370 degreeC. Moreover, 50% distillation point (T50) becomes like this. Preferably it is 340-440 degreeC, More preferably, it is 360-430 degreeC, More preferably, it is 370-420 degreeC. Moreover, 90% distillation point (T90) becomes like this. Preferably it is 405-465 degreeC, More preferably, it is 415-455 degreeC, More preferably, it is 425-445 degreeC. Moreover, an end point (FBP) becomes like this. Preferably it is 430-490 degreeC, More preferably, it is 440-480 degreeC, More preferably, it is 450-490 degreeC. Moreover, T90-T10 becomes like this. Preferably it is 60-140 degreeC, More preferably, it is 70-130 degreeC, More preferably, it is 80-120 degreeC. Moreover, FBP-IBP becomes like this. Preferably it is 140-200 degreeC, More preferably, it is 150-190 degreeC, More preferably, it is 160-180 degreeC. Further, T10-IBP is preferably 40 to 100 ° C, more preferably 50 to 90 ° C, and further preferably 60 to 80 ° C. Moreover, FBP-T90 becomes like this. Preferably it is 5-60 degreeC, More preferably, it is 10-55 degreeC, More preferably, it is 15-50 degreeC.

  Further, regarding the distillation properties of the lubricating base oils (II) and (V), the initial boiling point (IBP) is preferably 310 to 400 ° C, more preferably 320 to 390 ° C, still more preferably 330 to 380 ° C. It is. Moreover, 10% distillation temperature (T10) becomes like this. Preferably it is 350-430 degreeC, More preferably, it is 360-420 degreeC, More preferably, it is 370-410 degreeC. The 50% distillation point (T50) is preferably 390 to 470 ° C, more preferably 400 to 460 ° C, still more preferably 410 to 450 ° C. Moreover, 90% distillation point (T90) becomes like this. Preferably it is 420-490 degreeC, More preferably, it is 430-480 degreeC, More preferably, it is 440-470 degreeC. Moreover, an end point (FBP) becomes like this. Preferably it is 450-530 degreeC, More preferably, it is 460-520 degreeC, More preferably, it is 470-510 degreeC. Moreover, T90-T10 becomes like this. Preferably it is 40-100 degreeC, More preferably, it is 45-90 degreeC, More preferably, it is 50-80 degreeC. Moreover, FBP-IBP becomes like this. Preferably it is 110-170 degreeC, More preferably, it is 120-160 degreeC, More preferably, it is 130-150 degreeC. T10-IBP is preferably 5 to 60 ° C, more preferably 10 to 55 ° C, and still more preferably 15 to 50 ° C. Moreover, FBP-T90 becomes like this. Preferably it is 5-60 degreeC, More preferably, it is 10-55 degreeC, More preferably, it is 15-50 degreeC.

  The initial boiling point (IBP) of the lubricating base oils (III) and (VI) is preferably 440 to 480 ° C, more preferably 430 to 470 ° C, and still more preferably 420 to 460 ° C. It is. Moreover, 10% distillation temperature (T10) becomes like this. Preferably it is 450-510 degreeC, More preferably, it is 460-500 degreeC, More preferably, it is 460-480 degreeC. The 50% distillation point (T50) is preferably 470 to 540 ° C, more preferably 480 to 530 ° C, still more preferably 490 to 520 ° C. Moreover, 90% distillation point (T90) becomes like this. Preferably it is 470-560 degreeC, More preferably, it is 480-550 degreeC, More preferably, it is 490-540 degreeC. Moreover, an end point (FBP) becomes like this. Preferably it is 505-565 degreeC, More preferably, it is 515-555 degreeC, More preferably, it is 525-565 degreeC. Moreover, T90-T10 becomes like this. Preferably it is 35-80 degreeC, More preferably, it is 45-70 degreeC, More preferably, it is 55-80 degreeC. Moreover, FBP-IBP becomes like this. Preferably it is 50-130 degreeC, More preferably, it is 60-120 degreeC, More preferably, it is 70-110 degreeC. Further, T10-IBP is preferably 5 to 65 ° C, more preferably 10 to 55 ° C, and still more preferably 10 to 45 ° C. Moreover, FBP-T90 becomes like this. Preferably it is 5-60 degreeC, More preferably, it is 5-50 degreeC, More preferably, it is 5-40 degreeC.

  In each of the lubricating base oils (I) to (VI), IBP, T10, T50, T90, FBP, T90-T10, FBP-IBP, T10-IBP, and FBP-T90 are set to the above preferable ranges. Further, it is possible to further improve the low temperature viscosity and further reduce the evaporation loss. In addition, about each of T90-T10, FBP-IBP, T10-IBP, and FBP-T90, when the distillation range is made too narrow, the yield of lubricating base oil is deteriorated, which is not preferable in terms of economy. .

  In the present invention, IBP, T10, T50, T90 and FBP mean distillate points measured in accordance with ASTM D 2887-97, respectively.

  Further, the residual metal content in the lubricating base oil according to the present invention is derived from the metal content contained in the catalyst and raw materials that are inevitably mixed in the manufacturing process, but it is preferable that the residual metal content be sufficiently removed. . For example, the contents of Al, Mo, and Ni are each preferably 1 mass ppm or less. If the content of these metals exceeds the above upper limit, the function of the additive blended with the lubricating base oil tends to be inhibited.

  In addition, the residual metal content as used in the field of this invention means the metal content measured based on JPI-5S-38-2003.

  Moreover, it is preferable that the lubricating base oil according to the present invention exhibits the RBOT life shown below according to its kinematic viscosity. For example, the RBOT life of the lubricating base oils (I) and (IV) is preferably 290 min or more, more preferably 300 min or more, and further preferably 310 min or more. The RBOT life of the lubricating base oils (II) and (V) is preferably 350 min or more, more preferably 360 min or more, and further preferably 370 min or more. The RBOT life of the lubricating base oils (III) and (VI) is preferably 400 min or more, more preferably 410 min or more, and further preferably 420 min or more. When the RBOT life is less than the lower limit, the viscosity-temperature characteristics and thermal / oxidative stability of the lubricating base oil tend to decrease. Further, when an additive is blended in the lubricating base oil, The effectiveness of the additive tends to decrease.

  The RBOT life as used herein refers to a composition in which 0.2% by mass of a phenolic antioxidant (2,6-di-tert-butyl-p-cresol; DBPC) is added to a lubricating base oil. It means the RBOT value measured according to JIS K 2514-1996.

  The lubricating base oil according to the present invention having the above structure is excellent in viscosity-temperature characteristics and low-temperature viscosity characteristics, has low viscosity resistance and stirring resistance, and further has improved thermal / oxidation stability and friction characteristics. Yes, it is possible to improve the friction reducing effect, and thus improve the energy saving property. In addition, when an additive is blended in the lubricating base oil according to the present invention, the function of the additive (the effect of improving the low temperature viscosity characteristics by the pour point depressant, the effect of improving the heat and oxidation stability by the antioxidant, the friction The friction reducing effect by the adjusting agent and the wear resistance improving effect by the antiwear agent can be expressed at a higher level. Therefore, the lubricating base oil according to the present invention can be suitably used as a base oil for various lubricating oils. Specifically, the lubricating base oil according to the present invention is applied to internal combustion engines such as gasoline engines for passenger cars, gasoline engines for motorcycles, diesel engines, gas engines, gas heat pump engines, marine engines, and power generation engines. Lubricating oil (lubricating oil for internal combustion engine), automatic transmission, manual transmission, continuously variable transmission, final reduction gear, etc. Hydraulic fluids used in hydraulic equipment such as compressor oil, turbine oil, industrial gear oil, refrigeration oil, rust prevention oil, heat medium oil, gas holder seal oil, bearing oil, paper machine oil, machine tool oil, Examples include slip guide surface oil, electrical insulating oil, cutting oil, press oil, rolling oil, heat treatment oil, etc., and by using the lubricating base oil according to the present invention for these applications, Improve oil viscosity-temperature characteristics, thermal / oxidation stability, energy saving, fuel efficiency, etc., and increase the life of each lubricant and reduce environmental impact substances at a high level. Become.

  In the lubricating oil composition of the present invention, the lubricating base oil according to the present invention may be used alone, or the lubricating base oil according to the present invention is used in combination with one or more other base oils. May be. When the lubricating base oil according to the present invention is used in combination with another base oil, the ratio of the lubricating base oil according to the present invention in the mixed base oil is preferably 30% by mass or more. 50% by mass or more is more preferable, and 70% by mass or more is still more preferable.

Although it does not restrict | limit especially as another base oil used together with the lubricating base oil concerning this invention, As a mineral oil type | system | group base oil, solvent refined mineral oil whose kinematic viscosity in 100 degreeC is 1-100 mm < ² > / s, for example, hydrogen Examples include hydrocracked mineral oil, hydrorefined mineral oil, and solvent dewaxing base oil.

  Synthetic base oils include poly α-olefins or hydrides thereof, isobutene oligomers or hydrides thereof, isoparaffins, alkylbenzenes, alkylnaphthalenes, diesters (ditridecyl glutarate, di-2-ethylhexyl adipate, diisodecyl adipate, ditridec Decyl adipate, di-2-ethylhexyl sebacate, etc.), polyol ester (trimethylolpropane caprylate, trimethylolpropane pelargonate, pentaerythritol 2-ethylhexanoate, pentaerythritol pelargonate, etc.), polyoxyalkylene glycol, dialkyl Examples thereof include diphenyl ether and polyphenyl ether, and among them, poly α-olefin is preferable. As the poly α-olefin, typically, an oligomer or co-oligomer (1-octene oligomer, decene oligomer, ethylene-propylene co-oligomer, etc.) having 2 to 32 carbon atoms, preferably 6 to 16 carbon atoms, and those. Of the hydrides.

  The production method of the poly-α-olefin is not particularly limited. For example, Friedel-Crafts catalyst containing a complex of aluminum trichloride or boron trifluoride with water, alcohol (ethanol, propanol, butanol, etc.), carboxylic acid or ester. And a method of polymerizing α-olefin in the presence of a polymerization catalyst such as

These, among other base oils other than lubricating base oil according to the present invention, a viscosity index of 80 or higher,% C _P is 60 or more,% C _A base oil is 10 or less (hereinafter, "second lubricating It is preferable to use “oil base oil”.

The viscosity index of the second lubricating base oil is preferably 100 or more, more preferably 120 or more, preferably 170 or less, more preferably 135 or less, and its% _CP is preferably 70 or more, more preferably 75. or more, preferably 100 or less, more preferably 85 or less, preferably the% _{C A} is 3 or less, more preferably 2 or less, more preferably 1 or less, CCS viscosity at -35 ° C. is, 3000 mPa · More than s, Preferably it is 3500 mPa * s or more, Preferably it is 100,000 mPa * s or less, More preferably, it is 50000 mPa * s or less, More preferably, it is 15000 mPa * s or less.

The kinematic viscosity at 100 ° C. of the second lubricating base oil is preferably 5 mm ² / s or more, more preferably 6 mm ² / s or more, preferably 35 mm ² / s or less, more preferably 20 mm ² / s. It is s or less, More preferably, it is 12 mm < ² > / s or less, Most preferably, it is 8 mm < ² > / s or less. By using a second lubricating base oil having a kinematic viscosity at 100 ° C. of 5 mm ² / s or more, it has excellent anti-wear properties when mixed with soot, and has reduced viscosity during long-term use by reducing evaporation loss. By suppressing the increase and maintaining low friction performance, it is possible to improve the low temperature startability and the fuel efficiency during the cold state by using the one having a thickness of 35 mm ² / s or less.

  The NOACK evaporation amount of the second lubricating base oil is not particularly limited, but is preferably 0 to 25% by mass, more preferably 2 to 15% by mass, and particularly preferably 5 to 10% by mass. By selecting a second lubricant base oil having a NOACK evaporation amount within the above range, it is easy to maintain low friction performance by reducing evaporation loss and suppressing increase in viscosity even during long-term use. It is particularly preferable to select one having a mass% or more because a lubricating oil composition having excellent low-temperature viscosity characteristics can be easily obtained.

  Further, the sulfur content of the second lubricating base oil is not particularly limited, but is preferably 1% by mass or less, more preferably 0.3% by mass or less, still more preferably 0.1% by mass or less, particularly Preferably it is 0.01 mass% or less. By selecting the second lubricating base oil having a sulfur content equal to or lower than the above upper limit, a composition with improved thermal / oxidative stability, high-temperature cleanability and low friction can be obtained.

  The iodine value of the second lubricating base oil is not particularly limited, but is preferably 8 or less, more preferably from the viewpoint that it is excellent in high temperature cleanliness and can reduce wear and friction under soot mixing. It is 6 or less, and is preferably 0.01 or more, more preferably 1 or more, and further preferably 3 or more in terms of economy in the production process.

  When the lubricating base oil according to the present invention and the second lubricating base oil are used in combination, the content of the second lubricating base oil is not particularly limited, but is preferably based on the total amount of the lubricating base oil. Is 10% by mass or more, more preferably 20% by mass or more, further preferably 30% by mass or more, preferably 90% by mass or less, more preferably 70% by mass or less, and further preferably 50% by mass or less.

When using a mixed base oil of the lubricating base oil according to the present invention and another lubricating base oil (including the second lubricating base oil), the kinematic viscosity at 100 ° C. of the mixed base oil is preferably It is preferably adjusted to 3 to 8 mm ² / s, more preferably 3.5 to ⁶ mm ² / s, and further to 4 to 5.5 mm ² / s, and the viscosity index is preferably 110 or more, more preferably 115. Above, more preferably 120 or more, particularly preferably 125 or more. Further, the sulfur content of the mixed base oil is not particularly limited and is preferably 0.3% by mass or less, but preferably 0.1% in that it can further enhance the life-span performance such as base number maintenance. It is not more than mass%, more preferably not more than 0.05 mass%, still more preferably not more than 0.005 mass%. Further, the NOACK evaporation amount of the mixed base oil is not particularly limited, but is preferably 5 to 25% by mass, more preferably 10 to 20% by mass, and particularly preferably 12 to 15% by mass. Further, the low temperature viscosity characteristics of the mixed base oil are not particularly limited, but the CCS viscosity at −30 ° C. is preferably 20000 mPa · s or less, more preferably 7000 mPa · s or less, and further preferably 3500 mPa · s or less. desirable. Here, the CCS viscosity means a viscosity at a specific temperature measured according to JIS K 2010.

  In the lubricating oil composition of the present invention, (A) an ashless friction modifier and (B) phosphorus-containing wear prevention are added to the lubricating base oil according to the present invention and other lubricating base oils used as necessary. A specific amount of each agent is blended.

  (A) As the ashless friction modifier, any compound usually used as an ashless friction modifier for lubricating oil can be used. For example, a hydrocarbon group having 6 to 30 carbon atoms, preferably an alkyl group or An amine compound, an imide compound, a fatty acid ester, a fatty acid amide, a fatty acid, an aliphatic alcohol, an aliphatic ether or the like having at least one alkenyl group, particularly a linear alkyl group having 6 to 30 carbon atoms or a linear alkenyl group in the molecule Ashless friction modifiers, or various ashless friction modifiers having 1 to 30 carbon atoms and 2 or more nitrogen atoms. In the present invention, among these ashless friction modifiers, an ashless friction modifier having an ester bond or an amide bond is preferable, and one or more selected from nitrogen, oxygen, and sulfur are used. Ashless friction modifiers having at least 3 atoms are preferred, and ashless friction modifiers selected from compounds having two or more nitrogen atoms and oxygen atoms and / or sulfur atoms, particularly those having an amide bond Is particularly preferred.

  Examples of the amine compound include linear or branched, preferably linear aliphatic monoamines having 6 to 30 carbon atoms, linear or branched, preferably linear aliphatic polyamines, or fatty acids thereof. An alkylene oxide adduct of a group amine can be exemplified. Examples of fatty acid esters include esters of linear or branched, preferably linear, fatty acids having 7 to 31 carbon atoms with aliphatic monohydric alcohols or aliphatic polyhydric alcohols. Examples of fatty acid amides include amides of linear or branched, preferably linear fatty acids having 7 to 31 carbon atoms, and aliphatic monoamines or aliphatic polyamines.

  Examples of suitable ashless friction modifiers having at least 3 atoms of one or more elements selected from nitrogen, oxygen, and sulfur include trihydric or higher polyhydric alcohols such as glycerin and sorbitan and oleic acid. Examples thereof include esters with fatty acids such as compounds having two or more nitrogen atoms, oxygen atoms and / or sulfur atoms, which will be described later.

Further, as various ashless friction modifiers selected from compounds having two or more nitrogen atoms and oxygen atoms and / or sulfur atoms, the nitrogen atoms are 2 to 10 atoms, preferably 2 to 4 atoms, particularly preferably. The compound which has 2 atoms and has an oxygen atom and / or a sulfur atom, Preferably it is 1-4 atoms, Preferably it has 1-2 atoms, The thing which has an amide bond among these is preferable. More specifically, examples thereof include hydrazide (oleic hydrazide and the like), semicarbazide (oleyl semicarbazide and the like), urea (oleyl urea and the like), ureido (oleyl and the like) exemplified in International Publication No. 2005/037967 pamphlet. Ureido, etc.), allophane amides (oleyl allophanamide, etc.) and derivatives thereof. Among these, one or more compounds selected from the group consisting of nitrogen-containing compounds represented by the following general formulas (1) and (2) and acid-modified derivatives thereof are particularly preferable.

In the general formula (1), R ¹ has a hydrocarbon group having 1 to 30 carbon atoms or a functional hydrocarbon group having 1 to 30 carbon atoms, preferably a hydrocarbon group having 10 to 30 carbon atoms or a functionality. A hydrocarbon group having 10 to 30 carbon atoms, more preferably an alkyl group having 12 to 24 carbon atoms, an alkenyl group or a hydrocarbon group having functionality, particularly preferably an alkenyl group having 12 to 20 carbon atoms, R ² and Each R ³ has a hydrocarbon group having 1 to 30 carbon atoms, a hydrocarbon group having 1 to 30 carbon atoms or hydrogen having functionality, preferably a hydrocarbon group having 1 to 10 carbon atoms, and functionality. A hydrocarbon group or hydrogen having 1 to 10 carbon atoms, more preferably a hydrocarbon group or hydrogen having 1 to 4 carbon atoms, more preferably hydrogen, and X ¹ represents oxygen or sulfur, preferably oxygen. As a most preferable example of the nitrogen-containing compound represented by the general formula (1), specifically, a compound in which X ¹ is oxygen and an acid-modified derivative thereof, more specifically, X ¹ is oxygen, R ¹ Is an alkyl or alkenyl group having 12 to 24 carbon atoms, R ² and R ³ are hydrogen, dodecyl urea, tridecyl urea, tetradecyl urea, pentadecyl urea, hexadecyl urea, heptadecyl urea, octadecyl urea, oleyl urea, etc. Examples include urea compounds having an alkyl group or an alkenyl group having 12 to 24 carbon atoms and acid-modified derivatives thereof. Among these, oleyl urea (C ₁₈ H ₃₅ —NH—C (═O) —NH ₂ ) and acid-modified derivatives thereof (boric acid-modified derivatives and the like) are particularly preferable examples.

In the general formula (2), R ⁴ is a hydrocarbon group having 1 to 30 carbon atoms or a hydrocarbon group having 1 to 30 carbon atoms, and preferably a hydrocarbon group or functionality having 10 to 30 carbon atoms. A hydrocarbon group having 10 to 30 carbon atoms, more preferably an alkyl group having 12 to 24 carbon atoms, an alkenyl group or a hydrocarbon group having functionality, particularly preferably an alkenyl group having 12 to 20 carbon atoms, and R ^{5 to} R ⁷ are each independently a hydrocarbon group having 1 to 30 carbon atoms, a hydrocarbon group having 1 to 30 carbon atoms or hydrogen having functionality, preferably a hydrocarbon group having 1 to 10 carbon atoms, and functionality. C1-C10 hydrocarbon group or hydrogen which has more preferably, C1-C4 hydrocarbon group or hydrogen, More preferably, hydrogen is shown.

Specific examples of the nitrogen-containing compound represented by the general formula (2) include a hydrazide having 1 to 30 carbon atoms or a functional hydrocarbon group having 1 to 30 carbon atoms and derivatives thereof. is there. When R ⁴ is a hydrocarbon group having 1 to 30 carbon atoms or a functional hydrocarbon group having 1 to 30 carbon atoms, and R ^{5 to} R ⁷ are hydrogen, the hydrocarbon group having 1 to 30 carbon atoms or the functionality Any of hydrazide having a hydrocarbon group having 1 to 30 carbon atoms, R ⁴ and R ^{5 to} R ⁷ is a hydrocarbon group having 1 to 30 carbon atoms or a hydrocarbon group having 1 to 30 carbon atoms having functionality. And when the remainder of R ^{5 to} R ⁷ is hydrogen, N-hydrocarbyl hydrazide having a hydrocarbon group having 1 to 30 carbon atoms or a hydrocarbon group having 1 to 30 carbon atoms having functionality (hydrocarbyl is a hydrocarbon group) Etc.). As a most preferable example of the nitrogen-containing compound represented by the general formula (2), R ⁴ is an alkyl group or alkenyl group having 12 to 24 carbon atoms, and R ⁵ , R ⁶ and R ⁷ are hydrogen. Hydrazide compounds having an alkyl or alkenyl group having 12 to 24 carbon atoms such as tridecanoic acid hydrazide, tetradecanoic acid hydrazide, pentadecanoic acid hydrazide, hexadecanoic acid hydrazide, heptadecanoic acid hydrazide, octadecanoic acid hydrazide, oleic acid hydrazide, and erucic acid hydrazide Examples thereof include acid-modified derivatives (boric acid-modified derivatives and the like). Among these, hydrazide oleic acid _{(C 17 H 33 -C (=} O) -NH-NH 2) and acid-modified derivatives, erucic acid hydrazide _{(C 21 H 41 -C (=} O) -NH-NH 2 ) And acid-modified derivatives thereof are particularly preferred examples.

  Production methods relating to various ashless friction modifiers having two or more nitrogen atoms in these molecules and preferred embodiments thereof are described in detail in the above-mentioned International Publication No. 2005/037967 pamphlet. It may be contained in the lubricating oil composition of the present invention in the form of a complex or salt with an organometallic compound. These ashless friction modifiers having 2 or more nitrogen atoms and oxygen atoms and / or sulfur atoms in these molecules are equivalent to or more than the friction reducers conventionally used such as molybdenum dithiocarbamate. In addition to exhibiting a reduction effect, the friction reduction effect is hardly deteriorated even when soot is mixed, and it is particularly preferable because the effect is easily maintained for a long time.

  The content of the (A) ashless friction modifier in the lubricating oil composition of the present invention is 0.01 to 10% by mass, preferably 0.1% by mass or more, more preferably, based on the total amount of the composition. It is 0.3% by mass or more, preferably 3% by mass or less, more preferably 2% by mass or less, and further preferably 1% by mass or less. When the content of the ashless friction modifier is less than 0.01% by mass, the effect of reducing friction due to the addition tends to be insufficient. When the content exceeds 10% by mass, the effect of an anti-wear additive or the like. Tends to be inhibited, or the solubility of the additive tends to deteriorate.

Component (B) in the lubricating oil composition of the present invention is a phosphorus-containing wear inhibitor. The phosphorus-containing antiwear agent is not particularly limited as long as it is an antiwear agent containing phosphorus in the molecule. For example, a phosphorus compound represented by the general formula (3) or a general formula (4) is used. It is preferably at least one compound selected from the group consisting of phosphorus compounds, metal salts thereof, amine salts thereof, and derivatives thereof.

In Formula (3), X ² , X ³ and X ⁴ each independently represent an oxygen atom or a sulfur atom, and R ⁸ , R ⁹ and R ¹⁰ each independently represent a hydrogen atom or a carbon atom having 1 to 30 carbon atoms. A hydrogen-containing group is shown.

In the formula (4), X ⁵ , X ⁶ , X ⁷ and X ⁸ are each independently an oxygen atom or a sulfur atom (one or two of X ⁵ , X ⁶ and X ⁷ are a single bond or (poly) oxyalkylene) R ¹¹ , R ¹² and R ¹³ each independently represent a hydrogen atom or a hydrocarbon-containing group having 1 to 30 carbon atoms.

Examples of the hydrocarbon-containing group having 1 to 30 carbon atoms represented by R ^{8 to} R ¹³ include an alkyl group, a cycloalkyl group, an alkenyl group, an alkyl-substituted cycloalkyl group, an aryl group, an alkyl-substituted aryl group, and an arylalkyl. A hydrocarbon-containing group having a hydrocarbon group such as a group can be exemplified, and the hydrocarbon group is preferably an alkyl group having 1 to 30 carbon atoms or an aryl group having 6 to 24 carbon atoms, more preferably It is a C3-C18, More preferably, it is a C4-C12 alkyl group. These hydrocarbon-containing groups may contain a hydrocarbon group and any one of an oxygen atom, a nitrogen atom and a sulfur atom in the molecule, but a hydrocarbon group composed of carbon and hydrogen is desirable.

  Examples of the phosphorus compound represented by the general formula (3) include phosphorous acid, monothiophosphorous acid, dithiophosphorous acid, trithiophosphorous acid; a nitrous acid having one hydrocarbon group having 1 to 30 carbon atoms. Phosphoric acid monoester, monothiophosphorous acid monoester, dithiophosphorous acid monoester, trithiophosphorous acid monoester; phosphorous acid diester having two hydrocarbon groups having 1 to 30 carbon atoms, monothiophosphorous acid diester , Dithiophosphite diester, trithiophosphite diester; phosphite triester having three hydrocarbon groups having 1 to 30 carbon atoms, monothiophosphite triester, dithiophosphite triester, trithiophosphite And acid triesters; and mixtures thereof.

  Examples of the phosphorus compound represented by the general formula (4) include phosphoric acid, monothiophosphoric acid, dithiophosphoric acid, trithiophosphoric acid, tetrathiophosphoric acid; phosphoric acid monoester having one hydrocarbon group having 1 to 30 carbon atoms. Monothiophosphoric acid monoester, dithiophosphoric acid monoester, trithiophosphoric acid monoester, tetrathiophosphoric acid monoester; phosphoric acid diester having two hydrocarbon groups having 1 to 30 carbon atoms, monothiophosphoric acid diester, dithiophosphoric acid diester, trithiophosphoric acid Diesters, tetrathiophosphoric acid diesters; phosphoric acid triesters having three hydrocarbon groups having 1 to 30 carbon atoms, monothiophosphoric acid triesters, dithiophosphoric acid triesters, trithiophosphoric acid triesters, tetrathiophosphoric acid triesters; 1-30 hydrocarbon groups ~ 3 phosphonic acid, phosphonic acid monoester, phosphonic acid diester; the above phosphorus compound having a (poly) oxyalkylene group having 1 to 4 carbon atoms; β-dithiophosphorylated propionic acid or dithiophosphoric acid and olefin cyclopentadiene or ( (Methyl) Derivatives of the above phosphorus compounds such as reaction products with methacrylic acid; and mixtures thereof.

  As the salt of the phosphorus compound represented by the general formula (3) or (4), the phosphorus compound may be a metal base such as a metal oxide, metal hydroxide, metal carbonate, metal chloride, ammonia, 1 to 1 carbon atoms. Examples thereof include salts obtained by allowing a nitrogen compound such as an amine compound having only 30 hydrocarbon groups or hydroxyl group-containing hydrocarbon groups in the molecule to act to neutralize part or all of the remaining acidic hydrogen.

  Specific examples of the metal in the metal base include alkali metals such as lithium, sodium, potassium and cesium, alkaline earth metals such as calcium, magnesium and barium, zinc, copper, iron, lead, nickel, silver and manganese. And heavy metals. Among these, alkaline earth metals such as calcium and magnesium and zinc are preferable.

  Specific examples of the nitrogen compounds include ammonia, monoamines, diamines, and polyamines. More specifically, the same compounds as the amine compounds that constitute the amine complex of molybdenum described later in the component (E2) can be exemplified. .

  Among these nitrogen compounds, aliphatic amines having an alkyl or alkenyl group having 10 to 20 carbon atoms such as decylamine, dodecylamine, dimethyldodecylamine, tridecylamine, heptadecylamine, octadecylamine, oleylamine and stearylamine (these are It may be linear or branched)).

As the component (B) in the present invention, the above-mentioned phosphorus-containing antiwear agent may be contained in the lubricating oil composition of the present invention containing at least one selected from the following (B1) to (B3) as a main component. Particularly desirable.
(B1) zinc dialkyldithiophosphate having a secondary alkyl group selected from 3 to 8 carbon atoms (B2) zinc dialkyldithiophosphate having a primary alkyl group selected from 3 to 8 carbon atoms (B3) phosphorus containing no sulfur Metal salt of acid contained

As said (B1) and (B2) component, what is represented by following General formula (5) can be illustrated.

In the formula, R ¹⁴ , R ¹⁵ , R ¹⁶ and R ¹⁷ may be the same or different, and are each independently a secondary alkyl group or primary alkyl group having 3 to 8 carbon atoms, preferably 3 to 6 carbon atoms. Secondary alkyl groups or primary alkyl groups having 6 to 8 carbon atoms, and may have alkyl groups having different carbon numbers and alkyl groups having different structures (secondary, primary) in the same molecule.

  In the present invention, it is preferable to contain a zinc dialkyldithiophosphate having a secondary alkyl group selected from 3 to 8 carbon atoms (B1) in that it is easy to suppress wear under soot mixing even at a low concentration, (B2) It is preferable to contain a zinc dialkyldithiophosphate having a primary alkyl group selected from 3 to 8 carbon atoms in that the oxidation stability can be further improved and the base number maintenance performance can be remarkably improved. It is most preferable to use the components (B1) and (B2) together in that the wear suppression performance and the base number maintenance performance under mixing can be improved at a high level with a good balance.

Note that any conventional method can be adopted as a method for producing zinc dithiophosphate, and is not particularly limited. Specifically, for example, an alkyl group corresponding to R ¹⁴ , R ¹⁵ , R ¹⁶ and R ¹⁷ may be used. It can be synthesized by reacting the alcohol with diphosphorus pentasulfide to produce dithiophosphoric acid and neutralizing it with zinc oxide.

The component (B3) is a metal salt of a phosphorus-containing acid that does not contain sulfur, and all of X ^{2 to} X ⁴ in the general formula (3) are oxygen atoms (X ² , X ^3, and X ⁴ 1 One or two of them may be a single bond or a (poly) oxyalkylene group), and all of X ^{5 to} X ⁸ in the general formula (4) are oxygen atoms (X ⁵ , X ⁶ and X ^A typical example is a metal salt of a phosphorus compound in which one or two of ⁷ may be a single bond or a (poly) oxyalkylene group. These (B3) components can be preferably used in that the long drain performance such as high temperature cleanliness, oxidation stability, and base number maintenance can be remarkably enhanced.

The structure of the metal salt of the phosphorus compound varies depending on the valence of the metal and the number of OH groups of the phosphorus compound, and therefore the structure is not limited at all. For example, when 1 mol of zinc oxide is reacted with 2 mol of phosphoric diester (one OH group), it is considered that a compound having a structure represented by the following general formula (6) is obtained as a main component. It is thought that there are some molecules

For example, when 1 mol of zinc oxide and 1 mol of phosphoric acid monoester (two OH groups) are reacted, a compound having a structure represented by the following general formula (7) is considered to be obtained as a main component. However, polymerized molecules are also thought to exist.

  Among these (B3) components, a salt of phosphorous acid diester having two alkyl groups or aryl groups having 3 to 18 carbon atoms and zinc, one alkyl group or aryl group having 3 to 18 carbon atoms Salt of phosphoric acid monoester and zinc, diester of phosphoric acid having two alkyl groups or aryl groups having 3 to 18 carbon atoms and zinc, two alkyl groups or aryl groups having 1 to 18 carbon atoms A salt of phosphonic acid monoester and zinc is preferable. These components can be arbitrarily blended in one kind or two or more kinds. In the present invention, an alkyl phosphate metal salt having one or two alkyl groups having 4 to 12 carbon atoms is preferable, and an alkyl group having 6 to 8 carbon atoms is preferable in that it is more excellent in wear resistance under soot mixing. Mono- and / or dialkyl phosphate metal salts having one or two are more preferable, and zinc mono- and di-2-ethylhexyl phosphate are particularly preferable.

  The upper limit of the phosphorus-containing antiwear agent in the lubricating oil composition of the present invention, preferably at least one selected from the above (B1), (B2) and (B3) is 0.2% by mass or less as the phosphorus amount. The lower limit is preferably 0.1% by mass or less, more preferably 0.08% by mass or less, and particularly preferably 0.06% by mass or less. The amount is 0.01% by mass or more, preferably 0.02% by mass or more, and particularly preferably 0.04% by mass or more.

  When the content of the phosphorus-containing wear inhibitor exceeds 0.2% by mass as phosphorus, it is not preferable because the high-temperature cleanliness and the base number maintainability are remarkably deteriorated, and 0.09 to 0.2% by mass In this case, it is preferable in that wear does not remarkably occur even in the presence of soot, but it is 0.08% by mass or less in terms of lowering sulfur, lowering phosphorus, or improving high-temperature cleanability and base number maintenance. It is desirable.

  The lubricating oil composition of the present invention contains the lubricating base oil according to the present invention, (A) an ashless friction modifier, and (B) a phosphorus-containing antiwear agent, in order to further enhance its performance. Or, depending on the use and required performance of the lubricating oil composition, one or more selected from (C) a metal detergent, (D) an ashless dispersant, and (E) an organomolybdenum compound. It is preferable to contain.

  The component (C) in the lubricating oil composition of the present invention is a metallic detergent. Specific examples include sulfonate detergents, phenate detergents, salicylate detergents, and carboxylate detergents, all of which can be used. In the present invention, it is particularly preferable to use a sulfonate-based detergent because it is particularly excellent in anti-wear property under soot mixing.

  The structure of the sulfonate detergent is not particularly limited. For example, an alkali metal salt of an alkyl aromatic sulfonic acid obtained by sulfonating an alkyl aromatic compound having a molecular weight of 100 to 1,500, preferably 200 to 700. Alternatively, alkaline earth metal salts are exemplified, and particularly, magnesium salts and / or calcium salts are preferably used. Specific examples of alkyl aromatic sulfonic acids include so-called petroleum sulfonic acids and synthetic sulfonic acids. As the petroleum sulfonic acid, those obtained by sulfonating an alkyl aromatic compound of a lubricating oil fraction of mineral oil or so-called mahoganic acid which is produced as a by-product when white oil is produced is used. Synthetic sulfonic acids include, for example, alkylbenzenes having linear or branched alkyl groups that are obtained as a by-product from an alkylbenzene production plant that is a raw material for detergents, or are obtained by alkylating polyolefin to benzene. As a raw material, a sulfonated one or a sulfonated dinonylnaphthalene is used. The sulfonating agent for sulfonating these alkyl aromatic compounds is not particularly limited, but usually fuming sulfuric acid or sulfuric acid is used.

  In the alkylation of the aromatic sulfonic acid, it is preferable to use a linear or branched (poly) olefin, for example, an oligomer of an olefin having 2 to 4 carbon atoms such as ethylene, propylene and butene. It is particularly preferable to use an ethylene oligomer. Alkali metal salts or alkaline earth metal salts of alkyl aromatic sulfonic acids alkylated with linear α-olefins having 6 to 40 carbon atoms derived from ethylene oligomers can particularly enhance the friction reducing effect. . The straight chain α-olefin having 6 to 40 carbon atoms mentioned here is preferably a straight chain α-olefin having 10 to 30 carbon atoms, more preferably 14 to 20 or 20 to 30 carbon atoms. It is desirable that it is a linear α-olefin having 20 to 26 carbon atoms in that the friction reducing effect is particularly excellent.

  In addition, as the sulfonate detergent, the above alkyl aromatic sulfonic acid may be directly reacted with an alkaline earth metal base such as magnesium and / or calcium alkaline earth metal oxide or hydroxide, or once sodium Not only neutral alkaline earth metal sulfonates obtained by replacing alkali metal salts such as salts and potassium salts with alkaline earth metal salts, but also neutral alkaline earth metal sulfonates and excess alkaline earths. Of basic alkaline earth metal sulfonates obtained by heating an alkali metal salt or alkaline earth metal base (hydroxide or oxide) in the presence of water, carbon dioxide and / or boric acid or borate Carbonates obtained by reacting the neutral alkaline earth metal sulfonate with an alkaline earth metal base in the presence Basic alkaline earth metal sulfonates, also borate overbased alkaline earth metal sulfonate is included.

  As the sulfonate detergent in the present invention, the above-mentioned neutral alkaline earth metal sulfonate, basic alkaline earth metal sulfonate, overbased alkaline earth metal sulfonate, and a mixture thereof can be used.

  As the sulfonate detergent in the present invention, a calcium sulfonate detergent or a magnesium sulfonate detergent is preferably used, and a calcium sulfonate detergent is particularly preferably used.

  Sulfonate detergents are usually commercially available in a state diluted with a light lubricating base oil or the like, and are available, but generally the metal content is 1.0 to 20% by mass, preferably Is preferably 2.0 to 16% by mass.

  The base number of the sulfonate detergent used in the present invention is arbitrary, and is usually 0 to 500 mgKOH / g. However, the base number is preferably 100 to 450 mgKOH / g from the viewpoint of excellent high temperature cleanability improvement effect per content. Is preferably 200 to 400 mgKOH / g.

  The base number referred to here is JIS K2501 “Petroleum products and lubricating oils-Neutralization number test method”. It means the base number by the perchloric acid method measured according to the above.

  The salicylate-based detergent is not particularly limited in its structure, but a metal salt of salicylic acid having 1 to 2 alkyl groups having 1 to 40 carbon atoms, preferably an alkali metal salt or an alkaline earth metal salt, particularly a magnesium salt And / or calcium salts are preferably used.

  The salicylate detergent used in the lubricating oil composition of the present invention preferably has a higher proportion of monoalkyl salicylic acid metal salt in view of excellent low-temperature viscosity characteristics. For example, the proportion of monoalkyl salicylic acid metal salt is 85. An alkyl salicylic acid metal salt in which the constituent ratio of the metal salt of dialkyl salicylic acid is 0 to 15 mol% and the constituent ratio of the metal salt of 3-alkyl salicylic acid is 40 to 100 mol% and / or its (over) basic A salt is preferred. In addition, the salicylate-based detergent in the present invention is preferably one containing a dialkyl salicylic acid metal salt from the viewpoint of excellent high-temperature cleanability and base number maintenance.

  The monoalkyl salicylic acid metal salt here means an alkyl salicylic acid metal salt having one alkyl group such as a 3-alkyl salicylic acid metal salt, a 4-alkyl salicylic acid metal salt, a 5-alkyl salicylic acid metal salt, and the like. The constituent ratio of the salt is 85 to 100 mol%, preferably 88 to 98 mol%, more preferably 90 to 95 mol% with respect to 100 mol% of the alkylsalicylic acid metal salt, and an alkylsalicylic acid metal salt other than the monoalkylsalicylic acid metal salt, for example, The composition ratio of the dialkyl salicylic acid metal salt is 0 to 15 mol%, preferably 2 to 12 mol%, and more preferably 5 to 10 mol%. Moreover, the structural ratio of 3-alkyl salicylic acid metal salt is 40-100 mol% with respect to 100 mol% of alkyl salicylic acid metal salt, Preferably it is 45-80 mol%, More preferably, it is 50-60 mol%. The total composition ratio of the 4-alkyl salicylic acid metal salt and the 5-alkyl salicylic acid metal salt corresponds to the composition ratio excluding the 3-alkyl salicylic acid metal salt and the dialkyl salicylic acid metal salt with respect to 100 mol% of the alkyl salicylic acid metal salt. And 0 to 60 mol%, preferably 20 to 50 mol%, more preferably 30 to 45 mol%. By containing a small amount of a metal salt of a dialkyl salicylic acid, a composition having excellent high-temperature cleanliness and low-temperature characteristics and excellent base number maintenance can be obtained. -The composition ratio of the alkyl salicylic acid metal salt can be relatively lowered, and the oil solubility can be improved.

  Moreover, as an alkyl group in the alkyl salicylic acid metal salt constituting the salicylate detergent, the carbon number is 10 to 40, preferably the carbon number is 10 to 19, or the carbon number is 20 to 30, and more preferably the carbon number is 14 to 18 or the carbon number. An alkyl group having 20 to 26, particularly preferably an alkyl group having 14 to 18 carbon atoms. Examples of the alkyl group having 10 to 40 carbon atoms include decyl group, undecyl group, dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, hexadecyl group, heptadecyl group, octadecyl group, nonadecyl group, icosyl group, heicosyl group, docosyl group, Examples thereof include alkyl groups having 10 to 40 carbon atoms such as a tricosyl group, a tetracosyl group, a pentacosyl group, a hexacosyl group, a heptacosyl group, an octacosyl group, a nonacosyl group, and a triacontyl group. These alkyl groups may be linear or branched, and may be a primary alkyl group, a secondary alkyl group, or a tertiary alkyl group. In the present invention, the desired metal salicylate is used. A secondary alkyl group is particularly preferred from the viewpoint of easily obtaining a salt.

  Examples of the metal in the alkyl salicylic acid metal salt include alkali metals such as sodium and potassium, alkaline earth metals such as calcium and magnesium, and are preferably calcium and magnesium, and particularly preferably calcium.

  The salicylate detergent can be produced by a known method and is not particularly limited. For example, 1 mol or more of a polymer such as ethylene, propylene, or butene or a copolymer of 1 mol or more of phenol is used. A method of alkylating with a C10-40 olefin, preferably a linear α-olefin such as an ethylene polymer, and carboxylating with carbon dioxide or the like, or 1 mol or more of the olefin per 1 mol of salicylic acid, preferably Reacts with a metal base such as an alkali metal or alkaline earth metal oxide or hydroxide to an alkyl salicylic acid mainly composed of a monoalkyl salicylic acid obtained by an alkylation method using the linear α-olefin. Or an alkali metal salt such as sodium salt or potassium salt Further, it can be obtained by replacing an alkali metal salt with an alkaline earth metal salt. Here, the reaction ratio of phenol or salicylic acid and olefin is preferably controlled to, for example, 1: 1 to 1.15 (molar ratio), more preferably 1: 1.05 to 1.1 (molar ratio). The composition ratio of the monoalkyl salicylic acid metal salt and the dialkyl salicylic acid metal salt can be controlled to a desired ratio, and by using a linear α-olefin as the olefin, a 3-alkyl salicylic acid metal salt and a 5-alkyl salicylic acid metal It is particularly preferable because the constituent ratio of the salt and the like can be easily controlled to a desired ratio of the present application and an alkyl salicylic acid metal salt having a secondary alkyl which is preferable in the present invention can be obtained as a main component. In addition, when a branched olefin is used as the olefin, it is easy to obtain only a 5-alkyl salicylic acid metal salt, but the oil solubility is improved by mixing a 3-alkyl salicylic acid metal salt or the like so as to have the desired configuration of the present application. This is an unfavorable method because the manufacturing process is diversified.

  The salicylate detergent preferably used in the lubricating oil composition of the present invention is an alkali metal or alkaline earth gold salicylate (neutral salt) obtained as described above, and an excess of alkali metal or alkaline earth metal. Basic salts obtained by heating a salt, alkali metal or alkaline earth metal base (a hydroxide or oxide of an alkali metal or alkaline earth metal) in the presence of water, carbon dioxide, boric acid or boron Also included are overbased salts obtained by reacting the neutral salt with a base such as an alkali metal or alkaline earth metal hydroxide in the presence of an acid salt.

  These reactions are usually carried out in a solvent (an aliphatic hydrocarbon solvent such as hexane, an aromatic hydrocarbon solvent such as xylene, a light lubricating base oil, etc.), and the metal content thereof is 1.0 to It is desirable to use 20% by mass, preferably 2.0 to 16% by mass.

  As the most preferable salicylate-based detergent used in the present invention, the composition ratio of the monoalkyl salicylic acid metal salt is 85 to 95 mol%, because it is excellent in the balance between high temperature cleanliness and base number maintenance and low temperature viscosity characteristics. The composition ratio of the dialkyl salicylic acid metal salt is 5 to 15 mol%, the composition ratio of the 3-alkyl salicylic acid metal salt is 50 to 60 mol%, and the composition ratio of the 4-alkyl salicylic acid metal salt and the 5-alkyl salicylic acid metal salt is 35 to 45 mol%. Certain metal salts of alkyl salicylic acid and / or (over) basic salts thereof. The alkyl group here is particularly preferably a secondary alkyl group.

  In the present invention, the base number of the salicylate detergent is usually 0 to 500 mgKOH / g, preferably 20 to 300 mgKOH / g, particularly preferably 100 to 200 mgKOH / g, and one or two selected from these These can be used together. The base number referred to here is 7. JIS K2501 “Petroleum products and lubricating oils-Neutralization number test method”. Means the base number measured by the perchloric acid method according to the above.

  Specifically, the phenate detergent is obtained by reacting sulfur with an alkylphenol having at least one linear or branched alkyl group having 4 to 40 carbon atoms, preferably 6 to 18 carbon atoms. Alkali earth metal salts, particularly magnesium salts and / or calcium salts, of Mannich reaction products of alkylphenols obtained by reacting alkylphenol sulfides or alkylphenols with formaldehyde are preferably used.

  For phenate detergents, the alkali metal or alkaline earth gold phenate (neutral salt) obtained as described above, and an excess of alkali metal or alkaline earth metal salt or alkali metal or alkaline earth metal base Basic salt obtained by heating (alkali metal or alkaline earth metal hydroxide or oxide) in the presence of water, or neutral salt in the presence of carbon dioxide, boric acid or borate Also included are overbased salts obtained by reacting with a base such as an alkali metal or alkaline earth metal hydroxide.

  These reactions are usually carried out in a solvent (an aliphatic hydrocarbon solvent such as hexane, an aromatic hydrocarbon solvent such as xylene, a light lubricating base oil, etc.), and the metal content thereof is 1.0 to It is desirable to use 20% by mass, preferably 2.0 to 16% by mass.

  The base number of the phenate detergent is usually 0 to 500 mgKOH / g, preferably 20 to 450 mgKOH / g.

  The metal ratio of these metallic detergents is not particularly limited and is usually 1 to 40, but in the present invention, it is preferably 2 or more, more preferably 3 or more, from the viewpoint of easily suppressing wear under soot mixing. Particularly preferably, at least one of 6 or more is preferably blended. From the viewpoint of stability, the metal ratio is preferably 20 or less, more preferably 15 or less. The metal ratio here is represented by the valence of the metal element in the metal-based detergent × metal element content (mol%) / soap group content (mol%), and the soap group is a metal salt. It is an organic group of the other party to be formed, and shows a sulfonic acid-containing group, a salicylic acid-containing group, a phenol-containing group, and the like.

  In the present invention, it is desirable to contain a sulfonate detergent and / or a phenate detergent having a metal ratio of 6 or more, preferably 8 to 15 in terms of superior wear prevention properties under soot mixing. A metal detergent having a metal ratio of less than 2, preferably 1.5 or less, particularly a sulfonate detergent and / or a salicylate detergent, particularly a sulfonate detergent, in that the friction and high temperature cleanability can be further improved. Desirably, a sulfonate detergent and / or phenate detergent having a metal ratio of 6 or more and a sulfonate detergent and / or a salicylate detergent having a metal ratio of less than 2 may be used in combination. More desirably, it is particularly desirable to use a sulfonate detergent having a metal ratio of 6 or more and a sulfonate detergent having a metal ratio of less than 2.

In the lubricating oil composition of the present invention, the content of the component (C) is 0.01 to 1% by mass, preferably 0.05 to 0.5% by mass, more preferably as a metal amount, based on the total amount of the lubricating oil composition. Is 0.1-0.3 mass%, More preferably, it is 0.15-0.25 mass%.
In addition, as the component (C), a sulfonate detergent and / or phenate detergent having a metal ratio of 6 or more and a sulfonate detergent and / or a salicylate detergent having a metal ratio of less than 2 are used in combination. Although there is no restriction | limiting in particular in the content rate in the case of making it contain, For the said reason, the metal amount (M1) resulting from the sulfonate detergent and / or phenate detergent with the said metal ratio of 6 or more, and the said metal ratio are less than 2 The metal amount (M2) resulting from the sulfonate detergent and / or the salicylate detergent having a metal ratio of less than 2 to the total amount of the sulfonate detergent and / or the salicylate detergent (M2). ) Mass ratio (M2 / (M1 + M2)) is preferably 0.001 to 0.5, more preferably 0.01 to 0.3, and still more preferably 0.05 to 0. 2, particularly preferably 0.08 to 0.12.

  The component (D) in the present invention is an ashless dispersant. Ashless dispersants include succinimides having an alkenyl or alkyl group derived from polyolefin, nitrogen-containing compounds such as benzylamine, polyamine, Mannich base, boron compounds such as boric acid and borate to these nitrogen-containing compounds, Examples thereof include phosphorus compounds such as (thio) phosphoric acid and (thio) phosphate, derivatives obtained by acting an organic acid, hydroxy (poly) oxyalkylene carbonate, and the like.

  In the present invention, one or two or more arbitrarily selected from these can be blended. Here, the alkenyl group or the alkyl group may be linear or branched. Specifically, preferred are olefin oligomers such as propylene, 1-butene and isobutylene, and ethylene and propylene co-oligomers. Branched alkyl groups derived from alkenyl groups, branched alkenyl groups, and the like, and branched alkyl groups and branched structures derived from polybutene (polyisobutene) having a number average molecular weight of 700 to 5,000, particularly 900 to 5,000. An alkenyl group is preferred.

  The weight average molecular weight of the ashless dispersant used in the present invention needs to be 3000 to 20000, and preferably the weight average molecular weight of the ashless dispersant is 4000 to 15000. When the weight average molecular weight is less than 3000, the molecular weight of the non-polar polybutenyl group is small and the sludge dispersibility is poor, and the amine portion of the polar group which may become an active site for oxidative degradation is relatively increased and oxidized. On the other hand, the weight average molecular weight is preferably 20000 or less and particularly preferably 15000 or less from the viewpoint of preventing the deterioration of the low temperature viscosity characteristics. Here, the weight average molecular weight means that two columns of GHSHR-M (7.8 mm ID × 30 cm) manufactured by Tosoh Corporation are used in series on a 150-CALC / GPC apparatus manufactured by Waters, and tetrahydrofuran is used as a solvent. By means of temperature, 23 ° C., flow rate of 1 mL / min, sample concentration of 1% by mass, sample injection amount of 75 μL, and weight average molecular weight in terms of polystyrene measured with a detector differential refractometer (RI) are meant.

Examples of the ashless dispersant preferably used in the lubricating oil composition of the present invention include polybutenyl succinimide represented by the following general formula (8) or (9).

  PIB in the general formulas (8) and (9) represents a polybutenyl group, and is obtained from polybutene obtained by polymerizing a high-purity isobutene or a mixture of 1-butene and isobutene with a boron fluoride catalyst or an aluminum chloride catalyst. In the polybutene mixture, those having a vinylidene structure at the terminal are usually contained in an amount of 5 to 100 mol%. From the viewpoint of excellent sludge suppression effect, n is preferably an integer of 2 to 5, and preferably an integer of 3 to 4.

  Although there is no restriction | limiting in particular as a manufacturing method of the succinimide represented by General formula (8) or (9), For example, what chlorinated the said polybutene, Preferably the said high purity isobutene is a boron fluoride type catalyst. Polybutenyl succinic acid obtained by reacting polymerized highly reactive polybutene (polyisobutene), more preferably polybutene from which chlorine and fluorine have been sufficiently removed, with maleic anhydride at 100 to 200 ° C. is converted into diethylenetriamine, triethylenetetramine. It can be obtained by reacting with a polyamine such as tetraethylenepentamine or pentaethylenehexamine.

  When producing bissuccinimide, the polybutenyl succinic acid may be reacted twice as much as the polyamine (molar ratio), and when producing monosuccinimide, the polybutenyl succinic acid and the polyamine, etc. What is necessary is just to make it react by quantity (molar ratio). Among these, polybutenyl bissuccinimide is preferable from the viewpoint of excellent sludge dispersibility.

  The polybutene used in the above production method may contain a trace amount of fluorine and chlorine due to the catalyst in the production process. Therefore, the fluorine and chlorine content can be reduced by an appropriate method such as an adsorption method or sufficient water washing. It is preferable to use polybutene that has been sufficiently removed. The content of fluorine or chlorine is preferably 50 mass ppm or less, more preferably 10 mass ppm or less, still more preferably 5 mass ppm or less, and particularly preferably 1 mass ppm or less.

  In the step of obtaining polybutenyl succinic anhydride by reaction of polybutene and maleic anhydride, a chlorination method using chlorine is often applied conventionally. However, this method results in a large amount of chlorine (eg, about 2000 to 3000 ppm) remaining in the succinimide final product. On the other hand, in a method that does not use chlorine, for example, when the above highly reactive polybutene is used and / or in a thermal reaction method, chlorine remaining in the final product can be suppressed to an extremely low level (for example, 0 to 30 ppm). Therefore, in order to suppress the chlorine content in the lubricating oil composition to an amount in the range of 0 to 30 ppm by weight, the chlorination method is not used, and the method using the highly reactive polybutene and / or the thermal reaction method is used. The polybutenyl succinic anhydride obtained is preferably used.

  Moreover, as a derivative | guide_body of polybutenyl succinimide, in addition to the compound represented by the said General formula (8) or (9), boron compounds, such as a boric acid, alcohol, an aldehyde, a ketone, an alkylphenol, cyclic carbonate, organic It can be used as a so-called modified succinimide in which an oxygen-containing organic compound such as an acid is allowed to act to neutralize or amidate part or all of the remaining amino group and / or imino group. In particular, a boron-containing alkenyl (or alkyl) succinimide obtained by a reaction with a boron compound such as boric acid is advantageous in terms of thermal and oxidation stability.

  Examples of the boron compound that acts on the compound represented by the general formula (8) or (9) include boric acid, borates, and borate esters.

  Specific examples of boric acid include orthoboric acid, metaboric acid, and tetraboric acid.

  Examples of borates include alkali metal salts, alkaline earth metal salts or ammonium salts of boric acid, and more specifically, for example, lithium metaborate, lithium tetraborate, lithium pentaborate, perborate. Lithium borate such as lithium; sodium borate such as sodium metaborate, sodium diborate, sodium tetraborate, sodium pentaborate, sodium hexaborate, sodium octaborate; potassium metaborate, potassium tetraborate, Potassium borates such as potassium pentaborate, potassium hexaborate and potassium octaborate; calcium borates such as calcium metaborate, calcium diborate, tricalcium tetraborate, pentacalcium tetraborate and calcium hexaborate ; Magnesium metaborate, magnesium diborate, trimagnesium tetraborate, pentaborate Neshiumu, magnesium borate and magnesium hexaborate acid; and ammonium metaborate, ammonium tetraborate, ammonium pentaborate and ammonium borate such as ammonium eight borate.

  Examples of the boric acid ester include esters of boric acid and preferably an alkyl alcohol having 1 to 6 carbon atoms. More specifically, examples thereof include monomethyl borate, dimethyl borate, trimethyl borate, and boric acid. Examples include monoethyl, diethyl borate, triethyl borate, monopropyl borate, dipropyl borate, tripropyl borate, monobutyl borate, dibutyl borate, tributyl borate and the like.

  The succinimide derivative in which the boron compound is allowed to act is preferably used because it is excellent in heat resistance and oxidation stability.

  Specific examples of the oxygen-containing organic compound that acts on the compound represented by the general formula (8) or (9) include formic acid, acetic acid, glycolic acid, propionic acid, lactic acid, butyric acid, valeric acid, Carbon such as caproic acid, enanthic acid, caprylic acid, pelargonic acid, capric acid, undecyl acid, lauric acid, tridecanoic acid, myristic acid, pentadecanoic acid, palmitic acid, margaric acid, stearic acid, oleic acid, nonadecanoic acid, eicosanoic acid C1-C30 monocarboxylic acid, oxalic acid, phthalic acid, trimellitic acid, pyromellitic acid and other C2-C30 polycarboxylic acids or their anhydrides, ester compounds, C2-C6 Examples include alkylene oxide and hydroxy (poly) oxyalkylene carbonate.

By causing such an oxygen-containing organic compound to act, for example, part or all of the amino group or imino group in the compound represented by the general formula (8) or (9) is represented by the following general formula (10). Presumed to be a structure.

R ¹⁸ in the general formula (10) is a hydrogen atom, an alkyl group having 1 to 24 carbon atoms, an alkenyl group having 1 to 24 carbon atoms, an alkoxy group having 1 to 24 carbon atoms, or —O— (R ¹⁹ O) _m. A hydroxy (poly) oxyalkylene group represented by H; R ¹⁹ is an alkylene group having 1 to 4 carbon atoms; and m is an integer of 1 to 5. Among these, polybutenyl bissuccinimides mainly composed of those in which these oxygen-containing organic compounds are allowed to act on all amino groups or imino groups are preferably used since they are excellent in sludge dispersibility. Such a compound can be obtained, for example, by allowing 0.5 to (n-1) mol, preferably (n-1) mol of an oxygen-containing organic compound to act on 1 mol of the compound of formula (8). . A succinimide derivative having such an oxygen-containing organic compound acted thereon is excellent in sludge dispersibility, and in particular, one having hydroxy (poly) oxyalkylene carbonate acted thereon is preferable.

  As a preferred embodiment when the lubricating oil composition of the present invention contains an ashless dispersant, (D1) an ashless dispersant having a weight average molecular weight of 6500 or more and / or (D2) a weight average molecular weight of 3000 or more and boron It is preferable to contain an ashless dispersant, and these (D1) and (D) and (D1) and ( It is particularly preferable to use D2) together. Among these ashless dispersants, the above-mentioned polybutenyl succinimide and derivatives thereof, particularly those of the bis type are desirable. Here, the weight average molecular weight of (D1) component is 6500-20000, Preferably it is 8000 or more, More preferably, it is 9000 or more, Preferably it is 15000 or less, Most preferably, it is 12000 or less. Moreover, the weight average molecular weight of (D2) component is 3000-20000, Preferably it is 4000-6500, More preferably, it is 4500-5500.

  The content of the (D) ashless dispersant in the lubricating oil composition of the present invention is preferably 0.01 to 0.4 mass%, more preferably in terms of nitrogen element, based on the total amount of the composition. Is 0.02% by mass or more, more preferably 0.04% by mass or more, preferably 0.3% by mass or less, more preferably 0.2% by mass or less, and further preferably 0.1% by mass or less. It is. (D) When the content of the ashless dispersant is less than the above lower limit value, the wear preventing property under soot mixing is insufficient, and the sufficient cleansing effect tends to be hardly exhibited, while the content thereof When the amount exceeds the above upper limit, the above range is particularly preferable because the low-temperature viscosity characteristics and the demulsibility tend to deteriorate.

  In the case of using the component (D1), the content is preferably 0 in terms of nitrogen element based on the total amount of the composition in terms of improving the anti-wear property under soot mixing and excellent low-temperature viscosity characteristics. 0.005 to 0.1% by mass, and more preferably 0.01 to 0.04% by mass.

  In addition, when the component (D2) is used, the content is preferably 0.01% by mass or more in terms of nitrogen element based on the total amount of the composition in order to enhance sufficient high-temperature cleanability and thermal stability. More preferably, it is 0.02 mass% or more, preferably 0.3 mass% or less, more preferably 0.1 mass% or less, and still more preferably 0.04 mass% or less. For the same reason, the content is preferably 0.001% by mass or more, more preferably 0.005% by mass or more, and further preferably 0.008% by mass in terms of boron element based on the total amount of the composition. % Or more, preferably 0.2% by mass or less, more preferably 0.1% by mass or less, further preferably 0.04% by mass or less, and particularly preferably 0.02% by mass or less.

  Moreover, as (D2) component, the mass ratio (B / N ratio) of the boron content and nitrogen content is 0.1-5 normally, Preferably it is 0.1-1, More preferably, it is 0.00. It is particularly preferable to select and use one of 2 to 0.6.

  The mass ratio (B / N ratio) of boron content and nitrogen content (B / N ratio) resulting from (D) ashless dispersant in the present invention is to reduce wear and friction under soot mixing and to enhance high temperature cleanliness. In addition, it is desirable to make it contain 0.01 to 5, preferably 0.05 to 1, more preferably 0.1 to 0.4, and particularly preferably 0.1 to 0.2.

  The lubricating oil composition of the present invention has the above-described structure, reduces wear and friction under soot mixing, is excellent in high-temperature cleanliness, and can also improve startability and fuel economy in cold conditions. However, any additive commonly used in lubricating oils can be added to further improve its performance or depending on other purposes. In particular, the lubricating oil composition of the present invention preferably contains an organic molybdenum compound as the component (E).

  Examples of the organic molybdenum compound include (E1) an organic molybdenum compound (molybdenum friction modifier) selected from molybdenum dithiophosphate and molybdenum dithiocarbamate, and (E2) an organic molybdenum compound other than molybdenum dithiophosphate and molybdenum dithiocarbamate. Examples of the component (E2) include organic molybdenum compounds other than (E1), and organic sulfur compounds containing sulfur as a constituent element and organic molybdenum compounds not containing sulfur as a constituent element (molybdenum antioxidant). In the present invention, it is particularly desirable to contain the component (E2) as an essential component.

As a molybdenum dithiophosphate, the compound represented by following General formula (11) is mentioned, for example.

In the general formula (11), R ²⁰ , R ²¹ , R ²² and R ²³ may be the same or different, and have 2 to 30 carbon atoms, preferably 5 to 18 carbon atoms, more preferably 5 carbon atoms. A hydrocarbon group such as an alkyl group having ˜12 or a (alkyl) aryl group having 6 to 18 carbon atoms, preferably 10 to 15 carbon atoms. Y ¹ , Y ² , Y ³ and Y ⁴ each independently represent a sulfur atom or an oxygen atom.

  Preferred examples of the alkyl group include ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, A hexadecyl group, a heptadecyl group, an octadecyl group, etc. are mentioned, These may be a primary alkyl group, a secondary alkyl group, or a tertiary alkyl group, and may be linear or branched.

  Preferred examples of (alkyl) aryl groups include phenyl, tolyl, ethylphenyl, propylphenyl, butylphenyl, pentylphenyl, hexylphenyl, octylphenyl, nonylphenyl, decylphenyl, Examples thereof include a decylphenyl group and a dodecylphenyl group, and the alkyl group may be a primary alkyl group, a secondary alkyl group, or a tertiary alkyl group, and may be linear or branched. Further, these (alkyl) aryl groups include all substituted isomers in which the substitution position of the alkyl group to the aryl group is different.

  Specific examples of preferred molybdenum dithiophosphates include molybdenum sulfide diethyldithiophosphate, molybdenum sulfide dipropyldithiophosphate, molybdenum dibutyldithiophosphate, molybdenum dipentyldithiophosphate, molybdenum dihexyldithiophosphate, molybdenum dioctyldithiophosphate, molybdenum disulfide. Decyl dithiophosphate, sulfurized molybdenum didodecyl dithiophosphate, molybdenum di (butylphenyl) dithiophosphate, molybdenum di (nonylphenyl) dithiophosphate, sulfurized oxymolybdenum diethyldithiophosphate, sulfurized oxymolybdenum dipropyldithiophosphate, sulfurized oxymolybdenum dibutyldithiophosphate, sulfurized Oki Molybdenum dipentyldithiophosphate, sulfurized oxymolybdenum dihexyldithiophosphate, sulfurized oxymolybdenum dioctyldithiophosphate, sulfurized oxymolybdenum didecyldithiophosphate, sulfurized oxymolybdenum didodecyldithiophosphate, sulfurized oxymolybdenum di (butylphenyl) dithiophosphate, sulfurized oxymolybdenum di (nonylphenyl) Examples thereof include dithiophosphate (the alkyl group may be linear or branched, and the bonding position of the alkyl group of the alkylphenyl group is arbitrary), and mixtures thereof. As these molybdenum dithiophosphates, compounds having hydrocarbon groups having different carbon numbers and / or structures in one molecule can be preferably used.

As the molybdenum dithiocarbamate, specifically, a compound represented by the following general formula (12) can be used.

In the general formula (12), R ²⁴ , R ²⁵ , R ²⁶ and R ²⁷ may be the same or different and each has 2 to 24 carbon atoms, preferably 4 to 13 carbon atoms, or carbon atoms. A hydrocarbon group such as an (alkyl) aryl group having 6 to 24, preferably 10 to 15 carbon atoms is shown. Y ⁵ , Y ⁶ , Y ⁷ and Y ⁸ each independently represent a sulfur atom or an oxygen atom.

  Preferred examples of the alkyl group include ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, A hexadecyl group, a heptadecyl group, an octadecyl group, etc. are mentioned, These may be a primary alkyl group, a secondary alkyl group, or a tertiary alkyl group, and may be linear or branched.

  Preferred examples of (alkyl) aryl groups include phenyl, tolyl, ethylphenyl, propylphenyl, butylphenyl, pentylphenyl, hexylphenyl, octylphenyl, nonylphenyl, decylphenyl, Examples thereof include a decylphenyl group and a dodecylphenyl group, and the alkyl group may be a primary alkyl group, a secondary alkyl group, or a tertiary alkyl group, and may be linear or branched. Further, these (alkyl) aryl groups include all substituted isomers in which the substitution position of the alkyl group to the aryl group is different. Examples of molybdenum dithiocarbamate other than the above structure include those having a structure in which a dithiocarbamate group is coordinated to thio or polythio-trinuclear molybdenum as disclosed in WO98 / 26030 or WO99 / 31113.

  Specific examples of preferred molybdenum dithiocarbamates include molybdenum sulfide diethyldithiocarbamate, molybdenum dipropyldithiocarbamate, molybdenum dibutyldithiocarbamate, molybdenum dipentyldithiocarbamate, molybdenum dihexyldithiocarbamate, molybdenum dihexyldithiocarbamate, molybdenum dioctyldithiocarbamate, and molybdenum disulfide. Decyl dithiocarbamate, sulfurized molybdenum didodecyl dithiocarbamate, molybdenum di (butylphenyl) dithiocarbamate, molybdenum di (nonylphenyl) dithiocarbamate, sulfurized oxymolybdenum diethyldithiocarbamate, sulfurized oxymolybdenum dipropyldithiocarbamate, sulfurized oxymolybdenum dibutyldithiocarbamate Oki Molybdenum dipentyldithiocarbamate, sulfurized oxymolybdenum dihexyldithiocarbamate, sulfurized oxymolybdenum dioctyldithiocarbamate, sulfurized oxymolybdenum didecyldithiocarbamate, sulfurized oxymolybdenum didodecyldithiocarbamate, sulfurized oxymolybdenum di (butylphenyl) dithiocarbamate, sulfurized oxymolybdenum di (nonylphenyl) Examples thereof include dithiocarbamate (the alkyl group may be linear or branched, and the bonding position of the alkyl group of the alkylphenyl group is arbitrary), and mixtures thereof. As these molybdenum dithiocarbamates, compounds having hydrocarbon groups having different carbon numbers and / or structures in one molecule can also be preferably used.

  Examples of the organic molybdenum compound (E2) other than molybdenum dithiophosphate and molybdenum dithiocarbamate include organic molybdenum compounds containing sulfur as a constituent element other than (E1). Examples of organic molybdenum compounds containing sulfur as a constituent element include molybdenum compounds (for example, molybdenum oxide such as molybdenum dioxide and molybdenum trioxide, orthomolybdic acid, paramolybdic acid, molybdic acid such as (poly) sulfurized molybdic acid, these molybdenum Metal salts of acids, molybdates such as ammonium salts, molybdenum disulfide, molybdenum trisulfide, molybdenum pentasulfide, molybdenum sulfide such as polysulfide molybdenum, sulfurized molybdenum acid, metal salts or amine salts of sulfurized molybdenum acid, molybdenum chloride, etc. ) And sulfur-containing organic compounds (eg, alkyl (thio) xanthate, thiadiazole, mercaptothiadiazole, thiocarbonate, tetrahydrocarbylthiuram disulfide, bis (di (thio) hydrocarbi Dithiophosphonates), disulfides, organic (poly) sulfides, sulfide esters, etc.) or complexes with other organic compounds, etc., or molybdenum sulfides, molybdenum sulfides, sulfides of molybdenum oxide, sulfides of molybdenum acids, etc. A complex of a sulfur-containing molybdenum compound and an amine compound, an succinimide, an organic acid, an alcohol-free organic compound such as alcohol described later in the section of an organic molybdenum compound that does not contain sulfur as a constituent element, or a structure described later Molybdenum compounds that do not contain sulfur as an element, organic compounds that do not contain sulfur, and sulfur sources (elemental sulfur, hydrogen sulfide, phosphorus pentasulfide, sulfur oxide, inorganic sulfides, hydrocarbyl (poly) sulfides, sulfurized olefins, sulfurized esters) , Sulfurized wax, sulfurized carboxylic acid, alkyl sulfide Phenol, thioacetamide, thiourea) and may include those various such sulfur-containing organic molybdenum compound obtained by reacting. These sulfur-containing organomolybdenum compounds are described in detail in, for example, JP-A-56-10591 and US Pat. No. 4,263,152.

  As the organic molybdenum compound (E2) other than molybdenum dithiophosphate and molybdenum dithiocarbamate, an organic molybdenum compound that does not contain sulfur as a constituent element can be used.

  Specific examples of organic molybdenum compounds that do not contain sulfur as a constituent element include molybdenum-amine complexes, molybdenum-succinimide complexes, molybdenum salts of organic acids, and molybdenum salts of alcohols. Complexes, molybdenum salts of organic acids and molybdenum salts of alcohols are preferred.

The molybdenum - The molybdenum compounds constituting the amine complex, molybdenum trioxide or its hydrate _{(MoO 3 · nH 2 O)} , molybdic acid _(H 2 _MoO 4), molybdenum acid alkali metal salts _(M 2 _MoO 4; M represents an alkali metal), ammonium molybdate ((NH ₄ ) ₂ MoO ₄ or (NH ₄ ) ₆ [Mo ₇ O ₂₄ ] · 4H ₂ O), MoCl ₅ , MoOCl ₄ , MoO ₂ Cl ₂ , MoO ₂ Examples thereof include molybdenum compounds containing no sulfur such as Br ₂ and Mo ₂ O ₃ Cl ₆ . Among these molybdenum compounds, hexavalent molybdenum compounds are preferable from the viewpoint of the yield of the molybdenum-amine complex. Furthermore, from the viewpoint of availability, among the hexavalent molybdenum compounds, molybdenum trioxide or a hydrate thereof, molybdic acid, alkali metal molybdate, and ammonium molybdate are preferable.

  The amine compound constituting the molybdenum-amine complex is not particularly limited, and specific examples of the nitrogen compound include monoamines, diamines, polyamines, and alkanolamines. More specifically, methylamine, ethylamine, propylamine, butylamine, pentylamine, hexylamine, heptylamine, octylamine, nonylamine, decylamine, undecylamine, dodecylamine, tridecylamine, tetradecylamine, pentadecylamine , Hexadecylamine, heptadecylamine, octadecylamine, dimethylamine, diethylamine, dipropylamine, dibutylamine, dipentylamine, dihexylamine, diheptylamine, dioctylamine, dinonylamine, didecylamine, diundecylamine, didodecylamine, ditridecylamine Decylamine, ditetradecylamine, dipentadecylamine, dihexadecylamine, diheptadecylamine, dioctadecylamine, methyl ethyl Alkylamines having an alkyl group having 1 to 30 carbon atoms such as amine, methylpropylamine, methylbutylamine, ethylpropylamine, ethylbutylamine, and propylbutylamine (these alkyl groups may be linear or branched); Alkenyl amines having 2 to 30 carbon atoms such as ethenylamine, propenylamine, butenylamine, octenylamine, and oleylamine (these alkenyl groups may be linear or branched); methanolamine, ethanolamine, propanolamine , Butanolamine, pentanolamine, hexanolamine, heptanolamine, octanolamine, nonanolamine, methanol ethanolamine, methanol propanolamine, methanol butanol amine Alkanolamines having 1 to 30 carbon atoms such as ethanolpropanolamine, ethanolbutanolamine, and propanolbutanolamine (these alkanol groups may be linear or branched); methylenediamine, ethylenediamine, Alkylene diamine having 1-30 carbon atoms such as propylene diamine and butylene diamine; polyamines such as diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine; undecyldiethylamine, undecyldiethanolamine, dodecyldipropanol Amine, oleyl diethanolamine, oleyl propylene diamine, stearyl tetraethylene pentamine, etc. Examples thereof include compounds having an alkyl group or alkenyl group having 8 to 20 carbon atoms in the amine and heterocyclic compounds such as imidazoline; alkylene oxide adducts of these compounds; and mixtures thereof. Of these amine compounds, primary amines, secondary amines and alkanolamines are preferred.

  Carbon number of the hydrocarbon group which the amine compound which comprises a molybdenum-amine complex has becomes like this. Preferably it is 4 or more, More preferably, it is 4-30, Most preferably, it is 8-18. When the number of carbon atoms of the hydrocarbon group of the amine compound is less than 4, the solubility tends to deteriorate. Moreover, by setting the number of carbon atoms of the amine compound to 30 or less, the molybdenum content in the molybdenum-amine complex can be relatively increased, and the effects of the present invention can be further enhanced with a small amount of compounding.

  The molybdenum-succinimide complex is a complex of a sulfur-free molybdenum compound as exemplified in the description of the molybdenum-amine complex and a succinimide having an alkyl group or alkenyl group having 4 or more carbon atoms. Is mentioned. As the succinimide, a succinimide having at least one alkyl group or alkenyl group having 40 to 400 carbon atoms or an alkenyl group in the molecule described in the ashless dispersant, or a carbon number of 4 to 39, preferably carbon number. Examples thereof include succinimide having 8 to 18 alkyl groups or alkenyl groups. If the alkyl group or alkenyl group in the succinimide has less than 4 carbon atoms, the solubility tends to deteriorate. A succinimide having an alkyl group or an alkenyl group having more than 30 carbon atoms and not more than 400 carbon atoms can also be used. By setting the alkyl group or alkenyl group to 30 or less carbon atoms, molybdenum-succinimide is obtained. The molybdenum content in the complex can be relatively increased, and the effects of the present invention can be further enhanced with a small amount of compounding.

  Examples of the molybdenum salt of an organic acid include a salt of a molybdenum base such as molybdenum oxide or molybdenum hydroxide, molybdenum carbonate or molybdenum chloride exemplified in the description of the molybdenum-amine complex and an organic acid. It is done. As an organic acid, the phosphorus containing acid which does not contain sulfur illustrated in the term of the said (B3) component, and carboxylic acid are preferable.

  The carboxylic acid constituting the carboxylic acid molybdenum salt may be either a monobasic acid or a polybasic acid.

  As the monobasic acid, a fatty acid having 2 to 30 carbon atoms, preferably 4 to 24 carbon atoms, is used. The fatty acid may be linear or branched, and may be saturated or unsaturated. . Specifically, for example, acetic acid, propionic acid, linear or branched butanoic acid, linear or branched pentanoic acid, linear or branched hexanoic acid, linear or branched heptane Acid, linear or branched octanoic acid, linear or branched nonanoic acid, linear or branched decanoic acid, linear or branched undecanoic acid, linear or branched dodecane Acid, linear or branched tridecanoic acid, linear or branched tetradecanoic acid, linear or branched pentadecanoic acid, linear or branched hexadecanoic acid, linear or branched heptadecane Acid, linear or branched octadecanoic acid, linear or branched hydroxyoctadecanoic acid, linear or branched nonadecanoic acid, linear or branched icosanoic acid, linear or branched Henicosanoic acid, linear or branched Saturated fatty acids such as cosanoic acid, linear or branched tricosanoic acid, linear or branched tetracosanoic acid, acrylic acid, linear or branched butenoic acid, linear or branched pentenoic acid, Linear or branched hexenoic acid, linear or branched heptenoic acid, linear or branched octenoic acid, linear or branched nonenoic acid, linear or branched decenoic acid, Linear or branched undecenoic acid, linear or branched dodecenoic acid, linear or branched tridecenoic acid, linear or branched tetradecenoic acid, linear or branched pentadecenoic acid, Linear or branched hexadecenoic acid, linear or branched heptadecenoic acid, linear or branched octadecenoic acid, linear or branched hydroxyoctadecenoic acid, linear or branched nonadecene Acid, linear or branched Unsaturated fatty acids such as cocenoic acid, linear or branched heicosenoic acid, linear or branched docosenoic acid, linear or branched tricosenoic acid, linear or branched tetracosenoic acid, and the like And the like.

  Moreover, as a monobasic acid, in addition to the above fatty acid, a monocyclic or polycyclic carboxylic acid (which may have a hydroxyl group) may be used, and the carbon number thereof is preferably 4 to 30, and more preferably. Is 7-30. The monocyclic or polycyclic carboxylic acid is an aromatic carboxylic acid having 0 to 3, preferably 1 to 2 linear or branched alkyl groups having 1 to 30 carbon atoms, preferably 1 to 20 carbon atoms. Or cycloalkyl carboxylic acid etc. are mentioned, More specifically, (alkyl) benzene carboxylic acid, (alkyl) naphthalene carboxylic acid, (alkyl) cycloalkyl carboxylic acid, etc. can be illustrated. Preferable examples of the monocyclic or polycyclic carboxylic acid include benzoic acid, salicylic acid, alkylbenzoic acid, alkylsalicylic acid, and cyclohexanecarboxylic acid.

  Examples of polybasic acids include dibasic acids, tribasic acids, and tetrabasic acids. The polybasic acid may be a chain polybasic acid or a cyclic polybasic acid. Further, in the case of a chain polybasic acid, it may be either linear or branched, and may be either saturated or unsaturated. As the chain polybasic acid, a chain dibasic acid having 2 to 16 carbon atoms is preferable. Specifically, for example, ethanedioic acid, propanedioic acid, linear or branched butanedioic acid, linear Or branched pentanedioic acid, linear or branched hexanedioic acid, linear or branched heptanedioic acid, linear or branched octanedioic acid, linear or branched nonane diacid Acid, linear or branched decanedioic acid, linear or branched undecanedioic acid, linear or branched dodecanedioic acid, linear or branched tridecanedioic acid, linear or Branched tetradecanedioic acid, linear or branched heptadecanedioic acid, linear or branched hexadecanedioic acid, linear or branched hexenedioic acid, linear or branched heptenedioic acid Linear or branched octene diacid, linear or branched nonene diacid, linear or branched Branched decenedioic acid, linear or branched undecenedioic acid, linear or branched dodecenedioic acid, linear or branched tridecenedioic acid, linear or branched tetradecenedioic acid And linear or branched heptadecene diacid, linear or branched hexadecene diacid, alkenyl succinic acid, and mixtures thereof. As the cyclic polybasic acid, 1,2-cyclohexanedicarboxylic acid, 4-cyclohexene-1,2-dicarboxylic acid alicyclic dicarboxylic acid, phthalic acid or other aromatic dicarboxylic acid, trimellitic acid or other aromatic Examples thereof include aromatic tetracarboxylic acids such as tricarboxylic acid and pyromellitic acid.

  Examples of the molybdenum salt of alcohol include a salt of a molybdenum compound not containing sulfur as exemplified in the description of the molybdenum-amine complex and an alcohol. The alcohol is a monohydric alcohol, polyhydric alcohol, polyhydric alcohol. Any of a partial ester or partial ether compound of alcohol, a nitrogen compound having a hydroxyl group (alkanolamine, etc.), etc. may be used. Molybdic acid is a strong acid and forms an ester by reaction with alcohol. The ester of molybdic acid and alcohol is also included in the molybdenum salt of alcohol in the present invention.

  As the monohydric alcohol, those having 1 to 24 carbon atoms, preferably 1 to 12 carbon atoms, more preferably 1 to 8 carbon atoms are usually used. Such alcohols may be linear or branched and saturated. Or may be unsaturated. Specific examples of the alcohol having 1 to 24 carbon atoms include methanol, ethanol, linear or branched propanol, linear or branched butanol, linear or branched pentanol, and linear Linear or branched hexanol, linear or branched heptanol, linear or branched octanol, linear or branched nonanol, linear or branched decanol, linear or branched Undecanol, linear or branched dodecanol, linear or branched tridecanol, linear or branched tetradecanol, linear or branched pentadecanol, linear or branched hexadecane Decanol, linear or branched heptadecanol, linear or branched octadecanol, linear or branched nonadecanol, linear or branched icosa Lumpur, linear or branched Hen'ikosanoru, linear or branched Torikosanoru, such as linear or branched tetracosanol, and mixtures thereof.

  Moreover, as a polyhydric alcohol, the thing of 2-10 valence is preferable, Preferably it is 2-6 valence. Specific examples of the 2 to 10 polyhydric alcohol include, for example, ethylene glycol, diethylene glycol, polyethylene glycol (3 to 15 mer of ethylene glycol), propylene glycol, dipropylene glycol, and polypropylene glycol (3 to 15 of propylene glycol). Monomer), 1,3-propanediol, 1,2-propanediol, 1,3-butanediol, 1,4-butanediol, 2-methyl-1,2-propanediol, 2-methyl-1,3 -Dihydric alcohols such as propanediol, 1,2-pentanediol, 1,3-pentanediol, 1,4-pentanediol, 1,5-pentanediol, neopentylglycol; glycerin, polyglycerin (glycerin 2- Octamers such as diglycerin, triglyceride Phosphorus, tetraglycerin, etc.), trimethylolalkanes (trimethylolethane, trimethylolpropane, trimethylolbutane, etc.) and their 2- to 8-mer, pentaerythritol and their 2- to 4-mer, 1,2,4- Butanetriol, 1,3,5-pentanetriol, 1,2,6-hexanetriol, 1,2,3,4-butanetetrol, sorbitol, sorbitan, sorbitol glycerin condensate, adonitol, arabitol, xylitol, mannitol, etc. Polysaccharides of xylose, arabinose, ribose, rhamnose, glucose, fructose, galactose, mannose, sorbose, cellobiose, maltose, isomaltose, trehalose, sucrose, sugars, and mixtures thereof That.

  Examples of the partial ester of the polyhydric alcohol include compounds in which a part of the hydroxyl group of the polyhydric alcohol exemplified in the description of the polyhydric alcohol has been hydrocarbyl esterified, among which glycerin monooleate and glycerin dioleate. Sorbitan monooleate, sorbitandiolate, pentaerythritol monooleate, polyethylene glycol monooleate, polyglycerin monooleate and the like are preferable.

  Moreover, as the partial ether of the polyhydric alcohol, an ether bond is formed by condensation of polyhydric alcohols, a compound in which a part of the hydroxyl groups of the polyhydric alcohol exemplified in the description of the polyhydric alcohol is hydrocarbyl etherified. Compounds (such as sorbitan condensate) and the like, among which 3-octadecyloxy-1,2-propanediol, 3-octadecenyloxy-1,2-propanediol, polyethylene glycol alkyl ether and the like are preferable.

  Examples of the nitrogen compound having a hydroxyl group include alkanolamines exemplified in the description of the molybdenum-amine complex, and alkanolamides (diethanolamide, etc.) in which the amino group of the alkanol is amidated. Among them, stearyldiethanolamine Polyethylene glycol stearylamine, polyethylene glycol dioleylamine, hydroxyethyl laurylamine, oleic acid diethanolamide and the like are preferable.

  As the (E) organomolybdenum compound in the present invention, one or more sulfur-containing organomolybdenum compounds (E1) selected from molybdenum dithiophosphate and molybdenum dithiocarbamate are used because they are excellent in the initial friction reduction effect. It is preferable. Moreover, it is preferable to use organic molybdenum compounds (E2) other than molybdenum dithiophosphate and molybdenum dithiocarbamate because they are excellent in high-temperature cleanliness, suppress an increase in viscosity, and easily maintain fuel saving performance for a long period of time. As the component (E2), among those exemplified above, a sulfur-containing molybdenum compound (for example, molybdenum sulfide, molybdenum oxysulfide, a sulfide of molybdic acid, etc.) and an organic compound that does not contain sulfur as a constituent element (an amine compound, Complexes or salts with succinimides, alcohols, carboxylic acids, etc., molybdenum compounds that do not contain sulfur as constituent elements (oxymolybdenum, molybdic acid, etc.), and organic compounds that do not contain sulfur as constituent elements (amine compounds, succinic acid) An imide, alcohol, carboxylic acid, etc.) or a salt, a sulfur-containing molybdenum compound or a molybdenum compound that does not contain sulfur as a constituent element, an organic compound that does not contain sulfur as a constituent element, and a sulfur source One or more organic molybdenum selected from molybdenum compounds Compounds are preferred.

  In the present invention, it is particularly preferable to use (E2) in that it is excellent in high-temperature cleanliness, and a composition excellent in sustainability of initial fuel saving performance can be obtained even under soot mixing.

  In the composition of the present invention, when an organic molybdenum compound is used, the content is not particularly limited, but is preferably 0.001% by mass or more, preferably 0.001% by mass or more in terms of molybdenum element based on the total amount of the composition. It is 005 mass% or more, More preferably, it is 0.01 mass% or more. Moreover, it is preferably 0.2% by mass or less, preferably 0.1% by mass or less, more preferably 0.05% by mass or less, and particularly preferably 0.03% by mass or less. When the content is less than 0.001% by mass, the heat / oxidation stability of the lubricating oil composition becomes insufficient, and in particular, it tends to be impossible to maintain excellent cleanliness over a long period of time. On the other hand, when the content exceeds 0.2% by mass, an effect commensurate with the content cannot be obtained, and the storage stability of the lubricating oil composition tends to decrease.

  Examples of additives other than the organomolybdenum compound (E) that can be preferably added to the lubricating oil composition of the present invention include ashless antioxidants, organometallic antioxidants, viscosity index improvers, (B ) Additives such as anti-wear agents, corrosion inhibitors, rust inhibitors, anti-emulsifiers, metal deactivators, antifoaming agents, and colorants other than the component).

  As the ashless antioxidant, any ashless antioxidants such as phenolic antioxidants and amine antioxidants that are generally used in lubricating oils can be used. By adding the antioxidant, the antioxidant property of the lubricating oil composition can be further enhanced, and the oxidation stability, high temperature cleanability and base number maintaining property of the composition of the present invention can be further enhanced.

  Examples of phenolic antioxidants include 4,4′-methylenebis (2,6-di-tert-butylphenol), 4,4′-bis (2,6-di-tert-butylphenol), 4,4 ′. -Bis (2-methyl-6-tert-butylphenol), 2,2'-methylenebis (4-ethyl-6-tert-butylphenol), 2,2'-methylenebis (4-methyl-6-tert-butylphenol), 4,4′-butylidenebis (3-methyl-6-tert-butylphenol), 4,4′-isopropylidenebis (2,6-di-tert-butylphenol), 2,2′-methylenebis (4-methyl-6) -Nonylphenol), 2,2'-isobutylidenebis (4,6-dimethylphenol), 2,2'-methylenebis (4-methyl) 6-cyclohexylphenol), 2,6-di-tert-butyl-4-methylphenol, 2,6-di-tert-butyl-4-ethylphenol, 2,4-dimethyl-6-tert-butylphenol, 2, 6-di-tert-α-dimethylamino-p-cresol, 2,6-di-tert-butyl-4 (N, N′-dimethylaminomethylphenol), 4,4′-thiobis (2-methyl-6) -Tert-butylphenol), 4,4'-thiobis (3-methyl-6-tert-butylphenol), 2,2'-thiobis (4-methyl-6-tert-butylphenol), bis (3-methyl-4- Hydroxy-5-tert-butylbenzyl) sulfide, bis (3,5-di-tert-butyl-4-hydroxybenzyl) sulfide 2,2′-thio-diethylenebis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], tridecyl-3- (3,5-di-tert-butyl-4-hydroxy Phenyl) propionate, pentaerythrityl-tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], octyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) ) Propionate, octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate, 3-methyl-5-tert-butyl-4-hydroxyphenyl substituted fatty acid esters and the like are preferable examples. Can do. You may use these in mixture of 2 or more types.

  Examples of amine-based antioxidants include phenyl-α-naphthylamine, alkylphenyl-α-naphthylamine, and dialkyldiphenylamine. You may use these in mixture of 2 or more types.

  In addition, as the organometallic antioxidant, a known organometallic antioxidant containing a metal and having an antioxidant effect can be used, and the component (E2) of the organomolybdenum compounds described above Can be preferably used.

  You may mix | blend the said phenolic antioxidant, amine-type antioxidant, and organometallic antioxidant in combination.

  When the antioxidant is contained in the lubricating oil composition of the present invention, the content is usually 0.01 to 20% by mass, preferably 0.1 to 10% by mass, based on the total amount of the lubricating oil composition. Preferably it is 0.5-5 mass%. When the content exceeds 20% by mass, sufficient performance corresponding to the blending amount cannot be obtained. On the other hand, when the content is less than 0.01% by mass, the effect of improving the base number maintenance property is small. Each is not preferred.

Examples of the viscosity index improver include non-dispersed or dispersed viscosity index improvers. Specifically, non-dispersed or dispersed polymethacrylates, non-dispersed or dispersed ethylene-α-olefin copolymers or hydrides thereof, polyisobutylene or hydrides thereof, styrene-diene hydrogenated copolymers, Examples thereof include styrene-maleic anhydride ester copolymers, polymethacrylate-styrene copolymers, polymethacrylate-olefin copolymers, and polyalkylstyrenes. The weight average molecular weight of these viscosity index improvers is not particularly limited, and is usually 10,000 to 1,000,000, but is preferably 50,000 to 800,000 in terms of further improving fuel economy and excellent shear stability. More preferably, it is 100,000-600,000, Most preferably, it is 150,000-500,000. The PSSI of the viscosity index improver is not particularly limited, but is preferably 1 to 60, more preferably 10 to 40, and still more preferably 20 to 30. Here, PSSI (Permanent Shear Stability Index) is the following calculation using the kinematic viscosity at 100 ° C. before and after the shear stability test (ASTM D6278) and the kinematic viscosity at 100 ° C. of the base oil. formula:
PSSI (%) = {1− (kinematic viscosity after shearing−kinematic viscosity of base oil) / (kinematic viscosity before shearing−kinematic viscosity of base oil)} × 100
Means the index calculated by When the viscosity index improver is contained, the content is usually 0.1 to 20% by mass, preferably 1 to 15% by mass, and more preferably 3 to 10% by mass based on the total amount of the composition.

  As the antiwear agent other than the component (B), for example, a sulfur-based extreme pressure agent can be used, and an effect of suppressing wear under soot mixing can be expected.

  Examples of the sulfur-based extreme pressure agent include disulfides, polysulfides, sulfurized olefins, sulfurized oils and fats, sulfur-containing compounds such as sulfurized esters, dithiocarbamates, and zinc dithiocarbamates, and sulfurized oils and fats are most preferable. Among these compounds, the sulfur content in the sulfur-based extreme pressure agent is preferably 1 to 40% by mass, more preferably 5 to 20% by mass, and still more preferably 5 to 15% by mass. . Even if the sulfur content in the sulfur-based extreme pressure agent is too high, the effect of suppressing wear under soot mixing does not become an effect commensurate with the sulfur content, on the other hand, there is a possibility that the base number maintenance performance deteriorates, When the sulfur content in the sulfur-based extreme pressure agent is small, the effect of suppressing wear under soot mixing is small. As other antiwear agents, known ones such as boric acid esters, ashless antiwear agents, and metal antiwear agents can be used.

  In the lubricating oil composition of the present invention, the content of the anti-wear agent other than the component (B) is usually 0.01 to 10% by mass, preferably 0.1 to 5% by mass based on the total amount of the composition. %.

  Examples of the corrosion inhibitor include benzotriazole, tolyltriazole, thiadiazole, and imidazole compounds.

  Examples of the rust inhibitor include petroleum sulfonate, alkylbenzene sulfonate, dinonylnaphthalene sulfonate, alkenyl succinic acid ester, and polyhydric alcohol ester.

  Examples of the demulsifier include polyalkylene glycol nonionic surfactants such as polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, and polyoxyethylene alkyl naphthyl ether.

  Examples of metal deactivators include imidazoline, pyrimidine derivatives, alkylthiadiazoles, mercaptobenzothiazoles, benzotriazoles or derivatives thereof, 1,3,4-thiadiazole polysulfide, 1,3,4-thiadiazolyl-2,5-bis. Examples include dialkyldithiocarbamate, 2- (alkyldithio) benzimidazole, and β- (o-carboxybenzylthio) propiononitrile.

  When the lubricating oil composition of the present invention contains a pour point depressant, since the effect of adding the pour point depressant by the lubricating base oil according to the present invention is maximized, excellent low temperature viscosity characteristics (−40 MRV viscosity at a temperature of preferably 20000 mPa · s or less, more preferably 15000 mPa · s or less, and still more preferably 10,000 mPa · s or less). In addition, MRV viscosity at -40 degreeC here means MRV viscosity at -40 degreeC measured based on JPI-5S-42-93. For example, when a pour point depressant is blended with the base oils (II) and (V), the MRV viscosity at −40 ° C. can be 12000 mPa · s or less, more preferably 10000 mPa · s or less, and still more preferably. Can obtain a lubricating oil composition having extremely excellent low-temperature viscosity characteristics of 8000 mPa · s, particularly preferably 6500 mPa · s or less. In this case, the blending amount of the pour point depressant is 0.05 to 2% by mass, preferably 0.1 to 1.5% by mass, based on the total amount of the composition, but in particular the MRV viscosity can be lowered. The pour point depressant is preferably from 1 to 300,000, more preferably from 5 to 200,000, and more preferably fluid. As the point depressant, polymethacrylates are particularly preferable.

  As the antifoaming agent, any compound usually used as an antifoaming agent for lubricating oil can be used, and examples thereof include silicones such as dimethyl silicone and fluorosilicone. One or two or more compounds arbitrarily selected from these can be blended in any amount. Examples of antifoaming agents include silicone oil, alkenyl succinic acid derivatives, esters of polyhydroxy aliphatic alcohols and long chain fatty acids, methyl salicylate and o-hydroxybenzyl alcohol, aluminum stearate, potassium oleate, N-dialkyl-allylamine Nitroaminoalkanol, aromatic amine salt of isoamyl octyl phosphate, alkylalkylene diphosphate, metal derivative of thioether, metal derivative of disulfide, fluorine compound of aliphatic hydrocarbon, triethylsilane, dichlorosilane, alkylphenyl polyethylene glycol ether sulfide, fluoro Examples thereof include alkyl ethers.

  As the colorant, any compound that is usually used can be used, and any amount can be blended. Usually, the blending amount is 0.001 to 1.0% by mass based on the total amount of the composition. is there.

  When these additives are contained in the lubricating oil composition of the present invention, the content is based on the total amount of the composition, 0.005 to 5% by mass for the corrosion inhibitor, the rust inhibitor, and the demulsifier, respectively, and the metal inertness. 0.005 to 1% by mass for the agent, 0.01 to 1% by mass for the pour point depressant, 0.0001 to 1% by mass for the antifoaming agent, and 0.001 to 1.0% by mass for the colorant. Usually selected by range.

  The sulfur content in the lubricating oil composition of the present invention is not particularly limited, but is preferably 0.3% by mass or less, more preferably 0.26% by mass or less, and 0.2% by mass or less. More preferably, it is particularly preferably 0.15% by mass or less. When the sulfur content exceeds 0.3% by mass, the lifetimes of the oxidation catalyst, NOx storage reduction catalyst, and DPF of the exhaust gas aftertreatment device tend to be shortened. Further, the sulfated ash content of the lubricating oil composition of the present invention is preferably 1.2% by mass or less, more preferably 1.0% by mass or less, and still more preferably from the viewpoint of maintaining the performance of the exhaust gas aftertreatment device. Is 0.9% by mass or less, preferably 0.3% by mass or more, particularly 0.7% by mass or more, so that wear and friction under soot mixing can be reduced and high temperature cleanliness is also excellent. A composition can be obtained.

The kinematic viscosity at 100 ° C. of the lubricating oil composition of the present invention is usually 5 to 30 mm ² / s in that the lubricity of the engine or the like can be properly maintained, but it is easy to maintain the wear prevention property under soot mixing, It is preferably 8 to 25 mm ² / s, more preferably 9.3 to 16.3 mm ² / s, and particularly preferably 9.3 to 11.5 mm ² / s in that the frictional resistance due to stirring resistance can be suppressed.

  The viscosity index of the lubricating oil composition of the present invention is usually 140 or more, preferably 150 or more, more preferably 160 or more, and still more preferably 170 or more, from the viewpoint of improving the viscosity-temperature characteristics and fuel economy. In view of excellent shear stability, high-temperature cleanability and base number maintenance performance, it is preferably 250 or less, more preferably 200 or less, and even more preferably 190 or less.

  Furthermore, the lubricating oil composition of the present invention has a TBS viscosity at 150 ° C. of preferably 2.6 mPa · s or more, particularly 2.9 to 3.7 mPa · s, thereby further reducing wear particularly during soot mixing. The CCS viscosity at −25 ° C. is 3500 mPa · s or lower, or the CCS viscosity at −30 ° C. is 3250 mPa · s or lower. Thus, a lubricating oil composition suitable as 0W-20, 5W-20, 0W-30, 5W-30 grade engine oil, particularly 0W-30 engine oil can be obtained.

  The lubricating oil composition of the present invention is excellent in wear resistance and friction reduction performance, and suppresses increase in wear and friction due to soot mixing, which is particularly noticeable when the amount of phosphorus compound such as ZnDTP is reduced, and is long-term. This can be easily maintained over a long period of time, and the influence on the exhaust gas aftertreatment device can be mitigated. Therefore, the lubricating oil composition is suitable for diesel engines and direct injection gasoline engines equipped with exhaust gas aftertreatment devices such as DPF and various catalysts. Moreover, it can be used not only for engines for such applications, but also for gasoline engines, diesel engines, gas engines for motorcycles, automobiles, power generation, cogeneration, etc. Not only can it be suitably used for these various engines using fuel of 50 mass ppm or less, but it is also useful for various engines for ships and outboard motors. Further, a low sulfur fuel, for example, a fuel having a sulfur content of 50 mass ppm or less, more preferably 30 mass ppm or less, particularly preferably 10 mass ppm or less (for example, gasoline, light oil, kerosene, alcohol, dimethyl ether, LPG, natural gas, (Hydrogen, GTL (Gas Liquid) fuel, etc.) are suitable for lubricating oil for internal combustion engines. Further, since the lubricating oil composition of the present invention is also excellent in oxidation stability, lubricating oil for drive systems such as automatic or manual transmissions, grease, wet brake oil, hydraulic hydraulic oil, turbine oil, compressor oil, bearing oil Also, it can be suitably used as a lubricating oil such as refrigerator oil.

  EXAMPLES Hereinafter, although this invention is demonstrated more concretely based on an Example and a comparative example, this invention is not limited to a following example at all.

[Manufacture of base oil 1]
First, the fraction separated by distillation under reduced pressure in the step of refining the solvent refined base oil was subjected to hydrogenation after solvent extraction with furfural, and then dewaxed with a methyl ethyl ketone-toluene mixed solvent. A wax component (hereinafter referred to as “WAX1”), which was removed during solvent dewaxing and obtained as slack wax, was used as a base oil for a lubricating base oil. Table 1 shows the properties of WAX1.

  Next, hydroprocessing was performed using WAX1 as a raw material oil and a hydroprocessing catalyst. At this time, the reaction temperature and the liquid space velocity were adjusted so that the decomposition rate of normal paraffin in the raw material oil was 10% by mass or less.

  Next, about the to-be-processed object obtained by said hydrogenation process, in the temperature range of 315 degreeC-325 degreeC using the zeolite-type hydrodewaxing catalyst adjusted to noble metal content 0.1 to 5 weight%. Hydrodewaxing was performed.

  Furthermore, the to-be-processed object (raffinate) obtained by the above hydrodewaxing was hydrorefined using a hydrogenation catalyst. Thereafter, the light component was separated by distillation to obtain a base oil 1 having the composition and properties shown in Table 4. In Table 4, “the ratio of the components derived from normal paraffin in the urea adduct” is obtained by performing a gas chromatography analysis on the urea adduct obtained in the measurement of the urea adduct value. Yes (the same applies hereinafter).

  Next, a base oil 1 was added with a polymethacrylate pour point depressant (weight average molecular weight: about 60,000) generally used in automotive lubricating oil to obtain a lubricating oil composition. The addition amount of the pour point depressant was three conditions of 0.3% by mass, 0.5% by mass and 1.0% by mass based on the total amount of the composition. Next, the MRV viscosity at −40 ° C. was measured for each obtained lubricating oil composition. The results obtained are shown in Table 4.

[Manufacture of base oil 2]
In the production of the base oil 2, a wax obtained by further deoiling WAX1 (hereinafter referred to as "WAX2") was used as a raw material for the lubricating oil base oil. Table 2 shows the properties of WAX2.

  Next, a lubricating oil having the composition and properties shown in Table 4 was obtained by performing hydrotreatment, hydrodewaxing, hydrorefining and distillation in the same manner as base oil 1 except that WAX2 was used instead of WAX1. A base oil was obtained.

  Next, a lubricating oil composition containing a polymethacrylate pour point depressant was prepared in the same manner as in base oil 1 except that base oil 2 was used, and the MRV viscosity at −40 ° C. was measured. . The results obtained are shown in Table 4.

[Manufacture of base oil 3]
In the base oil 3, FT wax (hereinafter referred to as “WAX3”) having a paraffin content of 95% by mass and having a carbon number distribution of 20 to 80 was used. Table 3 shows the properties of WAX3.

  Next, a lubricating oil having the composition and properties shown in Table 4 was obtained by performing hydrotreatment, hydrodewaxing, hydrorefining and distillation in the same manner as base oil 1 except that WAX3 was used instead of WAX1. Base oil 3 was obtained.

  Next, a lubricating oil composition containing a polymethacrylate pour point depressant was prepared in the same manner as in base oil 1 except that base oil 3 was used, and the MRV viscosity at −40 ° C. was measured. . The results obtained are shown in Table 4.

  Table 5 shows the composition and properties of the base oil 4 and the base oil 5 as highly hydrocracked mineral oils that do not correspond to the lubricating base oil according to the present invention.

[Examples 1 and 2 and Comparative Examples 1 to 6]
In Examples 1 and 2 and Comparative Examples 1 to 6, the base oil 1 shown in Table 4, the base oil 5 shown in Table 5, and the following base oils 6 and 7 and additives are used, and shown in Tables 6 and 7. A lubricating oil composition having a composition was prepared. In Tables 4 and 5, the ratio of base oil is based on the total amount of base oil, and the amount of each additive is based on the total amount of composition.
(Base oil)
Base oil 6: poly α-olefin base oil (100 ° C. kinematic viscosity: 3.9 mm ² / s, viscosity index: 126, S: less than 0.01% by mass, −35 ° C. CCS viscosity: 1500 mPa · s, NOACK: 12% by mass)
Base oil 7: Ester base oil (100 ° C. kinematic viscosity 9.2 mm ² / s, viscosity index: 176, pour point: −30 ° C., S: less than 0.01% by mass)
(Additive)
A: oleyl urea B1: zinc dibutyl phosphate (phosphorus content: 13.2% by mass, sulfur content: 0% by mass, zinc content: 13% by mass)
B2: Mixture of sec-butyl-ZnDTP / sec-hexyl-ZnDTP (zinc content: 7.2% by mass, phosphorus content: 6.2% by mass, sulfur content: 14.9% by mass)
C1: calcium sulfonate (calcium content: 2.4% by mass, sulfur content: 2.9% by mass, metal ratio: 1.0)
C2: Overbased calcium sulfonate (calcium content: 12.7% by mass, sulfur content: 2.0% by mass, metal ratio: 12)
C-3: Calcium salicylate (calcium content: 2.1 mass%, metal ratio: 1.0)
D1: Bis-type polybutenyl succinimide (nitrogen content: 0.6 mass%, weight average molecular weight: 10,000)
D2: Modified boric acid of bis-type polybutenyl succinimide (nitrogen content: 1.5% by mass, B: 0.5% by mass, weight average molecular weight: 5000)
E1: Molybdenum dithiocarbamate (molybdenum content: 10% by mass, sulfur content: 10% by mass)
E2: Oxymolybdenum-ditridecylamine complex F: Alkyldiphenylamine G: Additive package containing ethylene-α-olefin copolymer viscosity index improver (PSSI = 24), polymethacrylate pour point depressant, antifoaming agent and the like.

  Next, the performance of the lubricating oil compositions of Examples 1 and 2 and Comparative Examples 1 to 6 was evaluated by the following evaluation method.

(1) High-speed four-ball wear test To prepare soot-mixed oil in a simulated manner, 1.5% by mass of carbon black is dispersed in each lubricating oil composition, and the following test is performed in accordance with JPI-5S-32-90. A four-ball wear test was performed under the conditions, and the wear scar diameter after the test was measured. The obtained results are shown in Tables 6 and 7. In this test, the smaller the wear scar diameter, the better the wear resistance.
(Test conditions)
Rotation speed: 1500rpm
Load: 294N
Test oil temperature: 110 ° C
Test time: 1 hour

(2) HFRR friction test For each lubricating oil composition, two types of test oil were prepared, one with carbon black dispersed at 1.5% by mass and the other without carbon black dispersed (new oil). The friction coefficient was measured under the following conditions using a testing machine. The obtained results are shown in Tables 6 and 7. In this test, the smaller the coefficient of friction, the better the fuel economy, and the smaller the coefficient of friction after the addition of carbon black, the better the friction reduction effect and the maintainability of soot mixed. To do.
(Test conditions)
Weight: 200g
Test oil temperature: 100 ° C
Amplitude: 1 mm
Frequency: 50Hz
Test time: 1 hour Friction coefficient measurement: Friction coefficient was averaged from 50 minutes to 60 minutes after the start of the test.

  As is clear from the results shown in Tables 6 and 7, it can be seen that the lubricating oil compositions of Examples 1 and 2 have significantly superior wear prevention performance under soot mixing, and the friction coefficient under soot mixing is also as follows. There is almost no increase compared to the coefficient of friction when soot is not mixed. This result shows that significant improvement has been achieved even when PAO base oil or conventional hydrocracked mineral oil is used instead of base oil 1 (Comparative Examples 1 to 6).

Claims (8)

  A lubricant base oil having a urea adduct value of 4% by mass or less and a viscosity index of 100 or more, an ashless friction modifier of 0.01 to 10% by mass based on the total amount of the composition, and a phosphorus amount of 0 A lubricating oil composition comprising: 0.01 to 0.2% by mass of a phosphorus-containing antiwear agent.   The lube base oil is hydrocracking / hydroisomerization so that the raw material oil containing normal paraffin has a urea adduct value of 4% by mass or less and a viscosity index of 100 or more. The lubricating oil composition according to claim 1, wherein the lubricating oil composition is produced by a production method including a step of performing crystallization. The lubrication according to claim 1 or 2, wherein the lubricating base oil has a kinematic viscosity at 100 ° C of 3.5 mm ² / s or more and a CCS viscosity at -35 ° C of 2000 mPa · s or less. Oil composition.   The lubricating oil composition according to any one of claims 1 to 3, wherein a NOACK evaporation amount of the lubricating base oil is 15% by mass or less. The product of kinematic viscosity (unit: mm ² / s) and NOACK evaporation (unit: mass%) at 40 ° C. of the lubricating base oil is 250 or less. The lubricating oil composition according to any one of the above.   6. The ashless friction modifier is a compound containing at least 3 atoms of one or more elements selected from nitrogen, oxygen, and sulfur. 2. The lubricating oil composition according to item 1.   The organic molybdenum compound other than molybdenum dithiocarbamate and molybdenum dithiophosphate is contained in an amount of 0.001 to 0.2% by mass as molybdenum based on the total amount of the composition. The lubricating oil composition according to claim 1. The lubricating oil composition according to any one of claims 1 to 7, wherein the lubricating oil composition is for a diesel engine or a direct injection gasoline engine.