KR20040041027A - Cold rolling oil for steel sheet - Google Patents

Abstract

In the present invention, when the steel sheet is cold rolled at high speed, productivity can be improved by high speed rolling, and oil deposition resistance and drainage treatment around the mill are excellent, and the cleaning failure in the cleaning process is solved. Provided is a lubricating oil from which cold rolled oil is obtained. The present invention is a lubricating oil for steel sheet cold rolled oil containing (a) a fat or oil having a fatty acid having 12 to 14 carbon atoms of 50% by weight or more among the fatty acids constituting the fat or oil and (b) a composite ester.

Description

COLD ROLLING OIL FOR STEEL SHEET}

The present invention relates to cold rolled oil of steel sheet and lubricating oil used therein.

As a rolling oil supply system in the cold rolling of a steel plate, a circulating rolling oil supply system and a small amount of rolling oil emulsion which supply a large amount of rolling oil emulsion to a steel plate and a roll, and circulate and use iron rolling emulsion after use, and remove iron wear There are two methods of a direct rolling oil supply system in which a large amount of water is supplied to a roll while simultaneously supplying the rolled steel sheet, and the used rolling oil emulsion is treated as drainage without circulating use.

Conventionally, in cold rolling for direct supply (hereinafter referred to as direct cold rolling), rolled oil added with palm oil or tallow alone or an oil enhancer, an extreme pressure additive, or the like is used, which is mixed with water and used as an emulsion of 6 to 20% by weight. come. However, since the emulsion of high concentration is prepared only by mechanical stirring, the particle size of the emulsion is unstable, and the amount of oil adhesion (hereinafter referred to as plate out) to the rolling roll or the rolled steel sheet is changed, thereby causing a problem of unstable lubrication. In addition, there is a problem that the oil recovery rate in the drainage treatment is not sufficient because the oil and water are difficult to separate.

In addition, from recent years, various cold rolling for rationalization of production, further high-speed rolling exceeding 1800m / min, and high tension for thinning of steel sheets, require direct cold rolling oil to have excellent lubricity, lubrication stability, and low cost.

In addition, conventional direct cold rolled oil mainly containing palm oil or tallow is inexpensive, but due to its high melting point, it is accumulated in the vicinity of the mill, which causes deterioration of the working environment and causes fire accidents. Low melting point is also required.

In addition, thin steel sheet such as tin plate is plated through the process of alkali cleaning and continuous annealing after rolling, and during these processes, problems such as poor cleaning, staining of the surface of the steel sheet due to roll deposits in the annealing furnace, plating defects, etc. It is issued. It is considered that this is because the steel sheet temperature after rolling is high and thermal deterioration of the adhered rolling oil occurs and the washability decreases. Although deterioration of thermal deterioration can be suppressed to some extent by addition of antioxidants such as antioxidants, it can be avoided by changing the cleaning conditions, but this leads to a decrease in productivity and high cost.

Various rolling oils are proposed as a response to these problems. For example, there are rolling oils described in JP-A 7-150184 as oil-soluble high molecular compounds, which are not sufficient in terms of lubrication stability because they are affected by the water quality of the water used. It did not solve the problem. In addition, there are rolled oils described in JP-A 9-53089, which use an amine salt of a polyester compound and an organic acidic phosphate ester. However, the problem of lubricity can be solved. The problem of the cleanliness during high-speed rolling has not been solved.

In addition, in the cold rolling by the conventional circulation rolling oil supply system (hereinafter referred to as cold rolling for circulation circulation supply), oily enhancers, extreme pressure agents, rust inhibitors, antioxidants, etc. are formulated by using tallow or palm oil as the base oil as rolling oil. This was made into O / W type emulsion with an emulsifier and water. Usually, a relatively low concentration of 1 to 10% by weight has been used. However, although the conventional cold rolled oil mainly composed of natural fats and oils is inexpensive, the melting point is high, so the accumulation of scum around the mill causes the working environment to worsen and cause fire accidents. In addition, there was a problem of lack of long-term circulation stability.

Further, in the case of further high-speed rolling exceeding 1800m / min, problems such as lack of lubricity and poor cleaning occur as in the case of direct cold rolling oil.

Various rolling oils are proposed as a response to these problems. For example, JP-A 10-231494 discloses a rolling oil using fats and oils and complex esters. This rolling oil can solve problems such as lubricity during high-speed rolling, long-term circulation stability, and cleanability when the steel sheet temperature after rolling is low (equivalent to low speed). When the steel sheet temperature is high, sufficient cleanability cannot be obtained.

The problem of the present invention is that when cold rolling a steel sheet at high speed, productivity can be improved by high-speed rolling, which has not been achieved with conventional rolling oil, without problems such as an increase in the cost of rolling oil and a decrease in lubrication stability. The present invention provides a cold rolled oil that is excellent in preventing deposition of oil and scum around a mill, drainage treatment and lubricity, and also solves a poor cleaning process in a washing process, and a lubricant used therefor.

The present invention relates to cold rolled oil of a steel sheet excellent in lubricity for use in cold rolling of steel sheets, stability of lubrication, stain resistance and wastewater treatment properties, and further excellent in cleanability in a washing step, and lubricating oil used therein.

In such a situation, the inventors of the present invention use cold rolled oil containing specific fats and oils and specific complex esters to reduce the deposition of the rolling oil around the mill, thereby avoiding problems such as fire risk and deterioration of workability. It was found that it was excellent in lubricity and can be rolled at high speed at a speed of 1800 m / min or more, and the cleanability was not lowered even when the steel sheet temperature after rolling was high due to the high speed rolling, and it was found to be very superior to the conventional cold rolled oil. . Further, it was found that by using a specific water-soluble high molecular compound in a specific amount ratio, the lubricity is further improved, the lubrication stability and drainage treatment can be improved, and the above problems can be solved.

That is, the present invention is a fat or oil (hereinafter referred to as component (a)) of which fatty acid having 12 to 14 carbon atoms is 50% by weight or more among the fatty acids constituting fats and oils (hereinafter, referred to as component (a)), and (b) complex esters (hereinafter, (b It is related with the lubricating oil for steel plate cold rolling oils containing, and the steel plate cold rolling oil containing this lubricating oil and water.

The lubricating oil for cold rolled oil for steel sheet of the present invention further includes (c) (c1) a homopolymer of a monomer represented by formula (1) or a salt thereof, (c2) two or more copolymers of this monomer, and (c3) one kind of this monomer. A water-soluble high molecular compound having a weight average molecular weight in the range of 10000 to 1000000, wherein the polymer is selected from a copolymer of one or more of (meth) acrylic acid, its salt, its alkyl ester or its alkylamide. It is preferable to contain one or more types of (c) component.

(Wherein R ¹ represents a hydrogen atom or a methyl group, R ² and R ³ represent an alkyl group of 1 to 3 carbon atoms, A represents -O- or -NH-, and m represents an integer of 1 to 3)

This invention also provides the method of cold rolling a steel plate using the steel plate cold rolling oil containing the said lubricating oil and water, and the use of the said lubricating oil as a steel plate cold rolling oil lubricating oil.

Detailed description of the invention

The component (a) of the cold rolling oil lubricating oil of the present invention is a fat or oil having a fatty acid having 12 to 14 carbon atoms of 50% by weight or more among the fatty acids constituting the fat or oil, and preferably a fat or oil having a fatty acid having 12 or more carbon atoms of 40% by weight, It may be natural or synthetic. Examples of the fats and oils include palm oil, palm kernel oil, babasian kernel oil, and kernel nuclear oil. For example, while animal and vegetable oils such as Uji and palm oil, which are conventionally used in direct cold rolled oil, contain glycerides of aliphatic fatty acids having 16 to 18 carbon atoms, these fats and oils contain glycerides of aliphatic saturated fatty acids having 12 to 14 carbon atoms. Its main component is low in melting point compared to tallow, palm oil and the like, and has an effect of reducing the deposition of rolled oil around the mill. In addition, since the iodine value is lower than that of tallow or palm oil, thermal deterioration of the rolled oil with a steel sheet is unlikely to occur, and therefore, it has an effect of suppressing a drop in the washability during high-speed rolling. The fractionated fats and oils, such as Uji olein and palm olein, also have a low melting point, which has the effect of reducing the deposition of the rolling oil around the mill, but on the contrary, the iodine value tends to cause thermal deterioration. The addition of a large amount of deterioration inhibitors such as antioxidants can suppress the degradation of the washability to some extent, but it is not preferable because the oil price increases. From the standpoint of rolling oil deposition and cleanability during high-speed rolling, the melting point is preferably 30 ° C. or less, and more preferably iodine value is 25 (I ₂ g / 100g) or less. If the kinematic viscosity at 40 ° C (according to JIS K2283) is 30 mm 2 / s or less, the lubricating oil using the same has a low kinematic viscosity. Can be. Moreover, as (a) component, the thing with little glyceride content of C8 aliphatic saturated fatty acid, especially the fats and oils whose ratio of a C8 or less fatty acid is 5 weight% or less among constituent fatty acids are the most preferable, More specifically, palm kernel It is particularly preferable in terms of low oil odor and low generation of fume at the work site during rolling, and excellent working environment.

Although one type of fats and oils which are these (a) components may be used, it can also mix and use 2 or more types. Moreover, it is preferable to use the addition amount in 50 weight% or more in a lubricating oil component as direct cold rolling oil. 75-99 weight% is more preferable, and 80-95 weight% is especially preferable at the point of the improvement of the washability at the time of high speed rolling.

Moreover, as cold rolling oil for circulation type supply, it can also add and use to fractionated fats and oils, such as palm oil or palm olein. It is preferable that the addition amount is used by 20 weight% or more in a lubricating oil component. 40-95 weight% is more preferable, and 50-90 weight% is especially preferable at the point of the improvement of the washability at the time of high speed rolling.

The complex esters of the component (b) of the present invention are ester compounds obtained from polybasic acids, polyhydric alcohols, monohydric alcohols and / or monovalent fatty acids, and have a kinematic viscosity of 40 ° C. or higher in terms of lubricity improvement of 400 mm 2 / s or more. Furthermore, it is preferable that it is a complex ester of 750 mm <2> / s or more, and at least 1 sort (s) of dimer acid and polymer acid of a C16-20 higher aliphatic unsaturated acid, and the residual carboxyl group or hydroxyl group of the partial ester obtained from polyols have 12 carbon atoms. It is more preferable that it is an ester compound of the weight average molecular weights 750-20000, esterified with the monohydric alcohol or monohydric fatty acid which is -22. If this molecular weight is 750 or more, lubricity is more excellent than fats and oils, and if it is 20000 or less, the solubility to a lubricating component is favorable, and also handleability is also favorable in terms of viscosity, and it is preferable. This molecular weight is more preferably 1000 to 10,000, and most preferably 1500 to 4000. In addition, the weight average molecular weight of (b) component is measured by the gel permeation chromatography (GPC) method of the following conditions.

(Condition)

Column: G2000H × L + G1000H × L (manufactured by Tosoh Corporation)

ㆍ Column Temperature: 40 ℃

Eluent: THF (tetrahydrofuran)

Detector: RI (Refractometer)

Injection amount: 3 wt% THF solution, 20µl

ㆍ liquid flow rate: 1.0ml / min

Molecular Weight Standard: Polystyrene

Dimer acid and polymeric acid used for manufacture of (b) component are C16-20 higher aliphatic monoenoic acid or dimeric acid and polymeric acid of a dienic acid, For example, a crude acid, oleic acid, linoleic acid, tall oil fatty acid And dimer acid and polymer acid. Examples of the polyols include propylene glycol, ethylene glycol, dipropylene glycol, diethylene glycol, neopentylglytol, butanediol, pentanediol, polyoxyethylene glycol, polyoxypropylene glycol, trimethylolpropane, pentaerythritol, and glycerin. Can be mentioned. Examples of the monohydric alcohol having 12 to 22 carbon atoms include lauryl alcohol, millystyl alcohol, cetyl alcohol, stearyl alcohol, behenyl alcohol, and oleyl alcohol. Examples of monovalent fatty acids having 12 to 22 carbon atoms include lauric acid, millic acid, palmitic acid, stearic acid, behenic acid, oleic acid, erucic acid, Uji fatty acid, palm oil fatty acid, palm oil fatty acid, and the like. .

The composite esters of component (b) have a larger number of ester groups and higher kinematic viscosity than fats and oils such as tallow, which have conventionally been used as a lubricating component, and thus have a significant improvement in lubricity.

Although 1 type may be sufficient as the complex ester of these (b) components, it can mix and use 2 or more types. Moreover, it is preferable that the addition amount is used by 1 weight% or more in a lubricating oil component. From the balance of lubricity and oil price, as for direct cold rolled oil, 1-25 weight% is more preferable, and 5-20 weight% is especially preferable. Moreover, as cold rolling oil for circulating-type supply, from the same viewpoint, 5-40 weight% is preferable in a lubricating oil component, and 10-30 weight% is more preferable.

In the lubricating oil for cold rolling oil of the present invention, the weight ratio of the component (a) and the component (b) is (a) / (b) = 75 as the direct cold rolling oil in terms of improving cleanability and lubricity during high-speed rolling. / 25-99 / 1 is preferable and 80 / 20-95 / 5 is especially preferable. Moreover, as cold rolling oil for circulating-type supply, (a) / (b) = 50 / 50-95 / 5 is preferable, and 63 / 37-90 / 10 is especially preferable.

The high molecular compound of (c) component used in the lubricating oil for cold rolling oils of this invention,

(1) A water-soluble polymer compound having a weight average molecular weight in the range of 10000 to 1000000 as a homopolymer of the monomer or a salt thereof represented by the formula (c)

(2) A water-soluble polymer compound having a weight average molecular weight in the range of 10000 to 1000000 as a copolymer of two or more kinds of monomers represented by formula (c) or salts thereof.

(3) As a copolymer of (c) at least 1 sort (s) of the monomer represented by Formula (1) and its salt, and at least 1 sort (s) of acrylic acid, methacrylic acid, these salts, these alkyl esters, and these alkylamides, Water-soluble high molecular compound having a weight average molecular weight in the range of 10000 to 1000000

It is at least one selected from.

Specific examples of the monomer represented by the formula (1) include dimethylaminomethyl acrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, diethylaminopropyl acrylate, dimethylaminoethylacrylamide, dimethylaminoethyl methacrylamide, Dimethylaminopropyl methacrylamide, diethylaminomethyl acrylamide, diethylaminomethyl methacrylamide, etc. are mentioned.

Moreover, as an acid which forms a salt with the said monomer, acetic acid, butyric acid, capric acid, caprylic acid, glycolic acid, succinic acid, tartaric acid, phosphoric acid, butyl phosphate, octylate phosphate, boric acid, etc. are mentioned, for example.

Moreover, in the acrylic acid and methacrylic acid copolymerized with the said monomer, as the salt, an alkali metal, ammonium, an alkylamine, a polyoxyethylene alkylamine, an alkanolamine etc., for example, butyl acrylate, Examples of the amidates include lauryl acrylate, butyl methacrylate and lauryl methacrylate. Examples thereof include acrylamide, dimethylacrylamide, and methacrylamide.

The polymer compound of component (c) preferably has a weight average molecular weight in the range of 10000 to 1000000, and 30000 to 500000, and in the case of 10000 or more, stability when emulsion-dispersed is good. The polymer compound itself is excellent in stability and has an appropriate viscosity, resulting in good handleability. In addition, the weight average molecular weight of (c) component analyzes molecular weight by GPC method of the following conditions after hydrolyzing a high molecular compound, and converts the original molecular weight from the result.

(Condition)

Column: G2000SW (silica gel system: manufactured by Tosoh Corporation) × 2

Column temperature: 40 ℃

Eluent: 0.1N Na chloride solution / acetonitrile = 70/30

Detector: RI (Refractometer)

Injection amount: 1 wt% eluent solution, 20 μl

ㆍ liquid flow rate: 0.4ml / min

Molecular Weight Standard: Polystyrenesulfonic Acid Na

The high molecular compound of (c) component can be used 1 type or in mixture of 2 or more types. Although the surface potential of the rolled oil particles is negative, the surface potential of the rolled oil particles becomes almost zero with the addition of the component (c), and the rolled oil particles are agglomerated to have a coarse particle diameter. Excellent lubricity. When the (c) component is further added, the surface potential of the rolled oil particles becomes positive and the protective colloidal action causes the rolled oil particles to have a large particle size and good emulsion dispersibility. Lubricity is exhibited, and long-term circulation stability is also good. When the component (c) is further added, the emulsion dispersibility is very good, but the rolled oil particle diameter becomes the medium particle diameter, and thus the plate out property is insufficient and the lubricity tends to be lowered. Therefore, in the case of direct cold rolling oil, the addition amount in the lubricating oil component is preferably 0.01 to 0.5% by weight, particularly preferably 0.01 to 0.1% by weight, from the viewpoint of the coagulation effect of the rolled oil particles. If the amount is in this range, the flocculation effect is excellent, and the rolling oil particle size is appropriate without being self-emulsifying or emulsion dispersion. Moreover, as cold rolling oil for circulating-type supply, 0.1-3 weight% is preferable and, as for the addition amount in a lubricating oil component from a rolling oil particle size and long-term circulation stability, 0.5-2 weight% is especially preferable. If the addition amount is in this range, the rolling oil particle size is large, and the long-term circulation stability is also excellent.

In addition to the above components, various known additives may be added to the lubricant for cold rolled oil of the present invention, for example, an oily agent, an extreme pressure agent, a rust preventive / corrosive agent, an antioxidant, an emulsifier, and the like, as necessary.

As the oil-based improving agent, for example, fatty acids such as oleic acid, tallow fatty acid, palm oil fatty acid and polymer oil of tall oil fatty acid can be used, and these can be added up to 10% by weight in the lubricating oil component.

As the phosphorus extreme pressure agent, for example, trioctyl phosphate, tricresyl phosphate, trioleyl phosphate, dioctyl phosphate, dilauric phosphate, tributyl phosphite, trioleyl phosphite, ditridecyl phosphate, dioleyl phosphate Aromatic amine salt of a spit, mono 2 ethylhexyl phosphate, etc. are mentioned. Moreover, as a sulfur type extreme pressure agent, for example, sulfurized fats and oils, such as a sulfide sulfide, a sulfurized tallow, and a sulfide vegetable oil ester, an active type and an inactive type of sulfide mineral oil, dibenzyl disulfide, a tertiary butyl disulfide, zinc- Dialkyl dithio phosphate etc. are mentioned. Although 1 type of these extreme pressure agents may be used, they can also be used in mixture of 2 types. Moreover, the addition amount is used in 0.5 to 5.0 weight% of a lubricating oil component. The larger the amount added, the better the lubricity. However, if the added amount exceeds 5.0% by weight, the oil price becomes expensive and the improvement of the baking resistance against increase becomes impractical. From the oil price and lubricity improvement effect, the range of 1.0 to 3.0 weight% is more practically preferable.

As antirust and anticorrosive, for example, alkenylsuccinic acid and derivatives thereof, fatty acids such as oleic acid, esters such as sorbitan monooleate, benzotriazole and derivatives thereof, other amines, and the like can be used. Up to 2% by weight can be added.

As the antioxidant, for example, 2,4-di-tert-butyl p-cresol, tetrakis [methylene-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] methane, etc. Aromatic amines, such as a phenol type compound, phenyl alpha-naphthylamine, and phenothiazine, etc. can be used, These can be added to 5 weight% with respect to a lubricating oil component.

As the emulsifier, for example, anionic surfactants such as oleic acid triethanolamine salt and petroleum sulfonate sodium salt, nonionic surfactants such as polyoxyethylene nonylphenyl ether, polyoxyethylene sorbitan trioleate, and the like can be used. These can be added up to 2% by weight in the lubricant component.

The lubricating oil for cold rolling oil of the present invention preferably has an iodine value of 5 to 50, more preferably 10 to 40, and even more preferably 10 to 35 from the viewpoint of alkali degreasing and economical efficiency. Moreover, from a viewpoint of reducing deposition of the rolling oil about a mill, 10-40 degreeC is preferable, as for melting | fusing point of the said lubricating oil, 15-35 degreeC is more preferable, and 20-30 degreeC is still more preferable.

The cold rolled oil of the present invention can be obtained by dispersing the lubricating oil of the present invention in water by a known method. In addition, you may add (c) component separately from other components including (a) and (b) component. Although the dilution ratio at this time is not specifically limited, Usually, the lubricating oil concentration is preferably 1 to 20% by weight, more preferably 6 to 20% by weight as the direct cold rolled oil, and preferably 1 as the cold rolled oil for circulating feed. What is-10 weight% is spray-fed and supplied to a rolling roll or a steel plate surface as an emulsion. If the concentration is low, the amount of plate out to the steel plate surface is small, and a sufficient lubricating effect is not obtained. Moreover, the said various additives can also be mix | blended with a rolling oil.

In cold rolling of steel sheets, the emulsion of palm oil and tallow is spray-sprayed on the rolling rolls or the steel sheet surface, so that rolling oil or scum is deposited around the mill. In the case of high-speed rolling, the surface temperature of the steel sheet rises, and the rolled oil with steel sheet deteriorates and becomes viscous, so the washability is remarkably decreased. In this invention, melting | fusing point of a rolling oil falls by containing complex ester of (b) component in fats and oils of the specific fatty acid composition of (a) component, and deposition of rolling oil and scum around mill is reduced. In addition, since the iodine value of the rolling oil is lowered, and the thermal deterioration resistance is significantly improved, the viscosity increase of the rolling oil with steel sheet decreases even with the increase of the steel plate surface temperature at the time of high-speed rolling, and the decrease in the washability is suppressed. In addition, the lubricity is remarkably improved. In addition, by adding an appropriate amount of the specific water-soluble high molecular compound of the component (c), as the direct cold rolled oil, the surface potential of the rolled oil particles is neutralized and largely grained by a kind of flocculation, so that the amount of plate out to the surface of the steel sheet is increased and the lubricity is increased. Leads to improvement. Moreover, since the rolling oil particle | grains large-sized by the protective colloid action of these water-soluble high molecular compounds are stably maintained for a long time, lubrication stability is also improved. Moreover, since these water-soluble high molecular compounds disperse | distribute rolling oil particle | grains uniformly, it also has an effect which prevents clogging of foreign substances, such as a spray nozzle. In addition, since the water-soluble high molecular compound chelates Ca ions and Fe ions, the rolling oil particle diameter is determined by the addition amount thereof, and exhibits excellent stability without being affected by water quality. Moreover, as cold rolling oil for circulating feed, the emulsion dispersion property is improved and durability against leakage of rolling wear powder and mechanical oil is improved, so that the rolling oil particle size can be maintained stably for a long time, and the initial good rolling lubrication activity can be maintained for a long time. have.

The cold rolled oil using the lubricating oil of the present invention has superior lubricity and washability as compared with conventional rolled oil, and therefore, productivity at high speed rolling can be improved. In addition, since the melting point is low, the deposition of rolling oil and scum around the mill is reduced, so that the risk of fire, poor appearance, and deterioration of workability can be improved. Moreover, since there is no fall of the washability at the time of high speed rolling, the increase of the operation cost by the conventional cold rolling oil can be avoided. In addition, since rolling oil emulsion properties are stable without being affected by water quality and excellent in long-term circulation stability, operation stability is improved as compared with conventional rolling oil, and thus steel sheet can be produced at a lower cost and with high efficiency.

EXAMPLE

Example 1

Using the various lubricating oils (Invention 1-6 and Comparative products 1-6) shown in Table 1 and Table 2, the rolling oil (Emulsion) whose density | concentration is 15 weight% is prepared according to a conventional method, and the test shown below Examples were evaluated for lubricity, alkali degreasing, drainage (ESI (%)) and particle size stability. The results were written together in Table 1 and Table 2.

<Test Example 1 (rolling test)>

Using the two-stage rolling mill (200 mm diameter x 200 mm width, SUJ-2, Hs = 90), the prepared single roll rolling test was carried out on the following conditions, and the rolling reduction ratio was 40%. Lubricity was evaluated by the rolling load (tonf / m) at the time of. If the rolling load is lower than 95% of the conventional palm oil (Comparative Product 1) value, the lubricity is good. Moreover, the degreasing property (also called alkali degreasing property) was evaluated by the water content area ratio (%) of what degreased the rolled steel sheet on condition of the following. Here, the water content area ratio was obtained by immersing the degreased rolled steel sheet in water at room temperature and taking out the water content area ratio (%) on the surface of the steel sheet visually. Moreover, when the water content rate is 80% or more, degreasing property is favorable.

(Rolling condition)

Rolled material: Mild steel (SPCC-B, 30mm width × 700mm length × 2mm thickness, Ra = 0.02㎛)

Roll roughness: It grind | polishes in a rolling direction with an abrasive paper, and adjusts it to Ra = 0.3-0.4 micrometer (Rz = 2.8- 3.2 micrometer).

Plate temperature: 100 ℃

Rolling Speed: 400m / min

Rolling rate: 40%

Rolled oil concentration: 15 wt%

Liquid condition: 80 ℃, 30ℓ

Stirring condition: M type homomixer 12000r / min

Spray volume: 0.5ℓ / min x 1 each at the top and bottom, 200㎪

(Degreasing condition)

Heat treatment: 150 ° C × 12 hours (in air) (This heat treatment is performed by assuming high-speed rolling in a real machine. Under this condition, it is equivalent to rolling at a speed of 1800 m / min or more at the real machine level. )

Degreasing solution: Caustic soda 2% + polyoxyethylene nonylphenyl ether (HLB = 12.4) 0.1% + sodium gluconate 0.1% solution

Degreasing method: dipping → electrolysis → rinse

Immersion condition: 80 ℃, 1 second

Electrolytic condition: 80 ℃, 5A / dm ² , 1 second

Rinse condition: 70 ℃ hot water spray (one side 1ℓ / min × 1 second).

<Test Example 2 (cyclic emulsion stability test)>

The circulating emulsification stability test was carried out under the following conditions using a circulating test apparatus on the prepared rolled oil, and the average particle diameter of the emulsion before and after Fe ion addition was measured by a Coulter counter (manufactured by BECKMAN COULTER) and emulsified at the same time. The stability index (ESI) and the plate out amount (adhesion amount) were measured. The particle size stability was evaluated from the absolute value (micrometer) of change of average particle diameter (volume distribution). Although 10 micrometers or less of the absolute amount of changes are levels which can be used, 5 micrometers or less are especially preferable because particle size stability is favorable. In addition, ESI is an index of wastewater treatment, and the lower the ESI, the better the wastewater treatment. In addition, the plate out amount is an index of lubricity and lubrication stability, and the larger the quantity and the smaller the change, the better. The amount of change in the amount of adhesion is positively correlated with the particle size stability, and it can be said that the amount of adhesion and the smallest absolute value of the amount of change in the average particle size (good particle size stability) are excellent in terms of emulsion stability.

(Circulation conditions)

Circulation pump: Spare pump (250ℓ / min), 50mm diameter pipe

Circulation amount: 100ℓ / min

Cycle time: 30 minutes

Rolled oil concentration: 15 wt%

Liquid condition: 80 ℃, 30ℓ

Fe ion: 5 mg / kg

(ESI measurement condition)

400 ml of the rolled oil emulsion was collected in a separating funnel, and allowed to stand for 5 minutes, and then the rolling oil concentration of the upper and lower layers having a predetermined capacity was measured (volume% was read using an oil flask, or weight% was read using an oil concentration meter). Next, ESI is calculated using the following formula.

ESI (%) = B / A × 100

A: Rolled oil concentration of 100 ml of the upper layer after standing.

B: Rolled oil concentration of 100 ml of lower layer after standing

(Measurement of plate out amount)

The rolling oil emulsion is sprayed on the test piece which measured the weight degreased previously on the following conditions, affixed rolling oil, and wash | cleaned with running water. The weight is measured after drying, and the adhesion amount (plate out amount, g / m <2>) is calculated from the weight difference of a test piece.

(Plate out condition)

Test piece: mild steel (SPCC-D, 100㎜ × 100㎜ × 0.5㎜)

Plate temperature: room temperature

Spray volume: 0.5ℓ / min on one side, 200㎪

Spray distance: 150 mm

Spray way: double sided vertical

Spray time: 1 second

Water flow rate: 3ℓ / min

Wash time: 1 second

Invention One 2 3 4 5 6 lubricant Composition (% by weight) (a) A 90.98 Maintenance B 87.00 90.92 85.96 80.96 75.96 C Maintenance D (b) Composite Ester A 5.00 20.00 Composite Ester B 10.00 10.00 Composite Ester C 15.00 5.00 (c) Polymer Compound A 0.04 0.02 Polymer Compound B 0.04 0.04 Polymer Compound C 0.08 Polymer Compound D Etc Additive A 3.0 4.0 4.0 4.0 4.0 2.0 Additive B 1.0 Additive C 1.0 Kinematic viscosity (mm2 / s, 40 ° C) 40 36 40 45 55 26 Iodine (I ₂ g / 100 g) 22 20 22 24 26 14 Melting Point (℃) (Rising Method) 26 27 26 25 24 25 Rolling oil properties Test Example 1 Lubricity (tonf / m) 600 560 550 540 530 570 Alkali Degreasing (%) 95 100 95 95 90 95 Test Example 2 Average particle size (㎛) 29 60 49 51 53 66 Particle Size Stability 8 One 0 0 0 One Amount of adhesion (g / ㎡) 1.5 4.5 4.8 4.8 4.9 4.0 ESI (%) 22 One 0.5 0.5 0.5 3

Comparative product One 2 3 4 5 6 lubricant Composition (% by weight) (a) A Maintenance B 95.97 C 100 99.93 96.0 87.0 Maintenance D 96.9 (b) Composite Ester A Composite Ester B 10.0 Composite Ester C Composite Ester D 2.0 (c) Polymer Compound A 0.1 Polymer Compound B 0.03 Polymer Compound C Polymer Compound D 0.07 Etc Additive A 2.0 4.0 3.0 Additive B 1.0 Additive D 1.0 Additive E 1.0 Kinematic viscosity (mm2 / s, 40 ° C) 40 43 40 42 28 55 Iodine (I ₂ g / 100 g) 52 50 52 51 18 50 Melting Point (℃) (Rising Method) 38 40 38 38 28 37 Rolling oil properties Test Example 1 Lubricity (tonf / m) 660 620 620 630 640 590 Alkali Degreasing (%) 30 40 30 30 100 20 Test Example 2 Average particle size (㎛) 26 35 62 19 56 28 Particle Size Stability 8 0 22 10 One 8 Amount of adhesion (g / ㎡) 1.2 3.0 4.5 1.0 5.0 1.5 ESI (%) 27 52 One 35 0.5 25

In the above table, fats and oils, complex esters, polymer compounds, and other additives are as follows.

Holding A... Palm oil (iodine viscosity 13, melting point 26 ° C, 40 ° C kinematic viscosity 25mm2 / s, proportion of fatty acids having 12 to 14 carbon atoms in constituent fatty acids and 72% by weight of fatty acids having 8 or less carbon atoms)

Holding B. Palm kernel oil (iodine: 28, melting point 28 ° C, 40 ° C kinematic viscosity 28 mm2 / s, proportion of fatty acids having 12 to 14 carbon atoms in constituent fatty acids, and 61% by weight of fatty acids having 8 or less carbon atoms)

Holding C. Palm oil (iodine viscosity of 52 mm, melting point 38 ° C, 40 ° C, kinematic viscosity 41 mm 2 / s, proportion of fatty acids having 12 to 14 carbon atoms in constituent fatty acids 1% by weight)

Holding D. Uji (iodine: 49, melting point 40 ° C, kinematic viscosity 43mm2 / s at 40 ° C, proportion of fatty acids having 12 to 14 carbon atoms in constituent fatty acids 4% by weight)

Composite ester A... Ester obtained from polymeric acid of oleic acid (dimer acid: polymeric acid of trimeric acid or more = 60:40 (weight ratio) / diethylene glycol / lauryl alcohol = 2/1/2 (molar ratio) (acid value 8, hydroxyl value 6, average molecular weight) Dynamic viscosity of 1800, 40 ℃ 820㎡ / s)

Composite ester B... Esters obtained from polymer acids of tall oil fatty acid (dimer acid: polymer acid of trimeric acid or higher = 75:25 (weight ratio) / pentaerythritol / lauric acid = 1/2/6 (molar ratio) (acid value 4, hydroxyl group 8, average) Molecular viscosity 3000, 40 ℃, kinematic viscosity 1000mm2 / s)

Composite ester C... Ester obtained from polymer acid of tall oil fatty acid (dimer acid: polymer acid of trimeric acid or more = 90: 10 (weight ratio) / trimethylolpropane / lauric acid = 1/2/4 (molar ratio) (acid value 3, hydroxyl value 6, Kinematic viscosity 450mm2 / s at average molecular weight of 1900 and 40 ℃

Composite ester D... Ester obtained from adipic acid / pentaerythritol / oleic acid / octyl alcohol = 0.9 / 1 / 1.8 / 0.2 (molar ratio) (acid value 3, hydroxyl value 35, average molecular weight 50000)

ㆍ polymer compound A. Copolymer of diethylaminoethyl methacrylate with phosphoric acid neutralization / sodium methacrylate = 4/5 (weight average molecular weight = 20,000)

ㆍ polymer compound B. Phosphoric acid neutralization of dimethylaminoethyl methacrylate / copolymer of sodium acrylate = 6/1 (weight average molecular weight = 600,000)

ㆍ polymer compound C. Glycolic acid neutralization of dimethylaminopropyl methacrylateamide / copolymer of sodium acrylate = 3/1 (weight average molecular weight = 100,000)

ㆍ polymer compound D. Caprylic acid neutralized product of homopolymer of diethylaminoethyl methacrylate (weight average molecular weight = 80,000)

Additive A... Oily Enhancer (Palm Oil Fatty Acid)

Additive B... Antioxidant (2,4-di-tert-butyl p-cresol)

Additive C... Trioleil Phosphate

Additive D. 4-octyldiphenylamine salt of butyl phosphate

Additive E... Polymeric acid of tall oil fatty acid (dimer acid: polymeric acid above trimeric acid = 7: 3 (weight ratio))

The iodine value of lubricating oil was measured according to the method of JIS K0070, and melting | fusing point (rising melting | fusing point) was measured by the method of the "standard retention analysis test method" (Chapter 2, Section 4.2, issued by Japan Petrochemical Society, 1996).

In Table 1 and Table 2, kinematic viscosity, iodine value and melting point of various direct cold rolling oil lubricants are written together. The melting point is an index of the rolling oil deposition around the mill, the lower the better the rolling oil deposition resistance. As is clear from the results shown in the table, the direct cold rolled oil of the present invention is superior in the degreasing resistance and the rolled oil deposit resistance compared to the comparative product. In particular, compared with the conventional palm oil of the comparative product 1, it is excellent in all the performances.

Example 2

Water was added to the various lubricating oils for cold rolling oil (the inventions 7 to 12 and the comparative products 7 to 12) for the circulation type feed shown in Tables 3 and 4 to prepare a rolling oil (emulsion) having a concentration of 3% by weight. In the test example shown in Fig. 2, the lubricity, washability, scum resistance, and long-term circulation stability were evaluated. The results were written together in Tables 3 and 4. In addition, in Table 3, 4, each component (part) is the same as that of Example 1.

<Test Example 3 (rolling test)>

The prepared rolling oil was subjected to a single pass rolling test under the following conditions using a two-stage rolling machine (200 mmφ × 200 mm width, SUJ-2, Hs = 90), and rolling at a reduction ratio of 40%. Lubricity was evaluated by load (tonf / m). If the rolling load is lower than 95% of the conventional wuji cold rolling oil (Comparative Product 7), the lubricity is good. Moreover, the degreasing property (alkali degreasing property) was evaluated by the water content area ratio (%) of what degreased the rolled steel sheet on condition of the following. Moreover, when the water content area ratio is 80% or more, degreasing property is favorable.

(Rolling condition)

Rolled material: Mild steel (SPCC-B, 30mm width × 700mm length × 2mm thickness, Ra = 0.02㎛)

Roll roughness: It grind | polishes in a rolling direction with an abrasive paper, and adjusts it to Ra = 0.3-0.4 micrometer (Rz = 2.8- 3.2 micrometer).

Plate temperature: 100 ℃

Rolling Speed: 400m / min

Rolling rate: 40%

Rolled oil concentration: 3 wt%

Liquid condition: 60 ℃, 10ℓ

Stirrer: M type homo mixer (manufactured by Special Vaporization Co., Ltd.)

RPM: 9000r / min

Spray amount: 2ℓ / min × 1 each up and down, 100㎪

(Degreasing condition)

Heat treatment: 150 ° C × 12 hours (in air) (This heat treatment is performed by assuming high-speed rolling in a real machine. Under this condition, it is equivalent to rolling at a speed of 1800 m / min or more at the real machine level. )

Degreasing solution: Caustic soda 2% + polyoxyethylene nonylphenyl ether (HLB = 12.4) 0.1% + sodium gluconate 0.1% solution

Degreasing method: dipping → electrolysis → rinse

Immersion condition: 80 ℃, 1 second

Electrolytic condition: 80 ℃, 5A / dm ² , 1 second

Rinse condition: 60 ℃ hot water spray (one side 1ℓ / min × 1 second).

Test Example 4 (Continuous Rolling Test)

About the various rolling oils which were prepared, the coil tension 3-pass rolling test was done on the following conditions using the said two-stage rolling machine, and the scum resistance was evaluated by the accumulation scum amount (g). If the amount of accumulation scum is less than 50% of the conventional Uji cold rolling oil (Comparative Product 7) value, the scum resistance is good. In addition, the particle size of the emulsion before and after the test was measured by a Coulter counter (multiizer, manufactured by BECKMAN COULTER), and the long-term circulation stability was evaluated from the absolute value of change in the average particle diameter (volume distribution) (µm). When the absolute amount of change is 2 µm or less, the particle size stability (long-term circulation stability) is good.

(Rolling condition)

Rolled material: Mild steel (SPCC-D, 50mm width × 100mm length × 1mm thickness, Ra = 0.5㎛)

Roll roughness: It adjusts to Ra = 1.5 micrometer.

Plate temperature: Room temperature

Rolling Speed: 10m / min

Rolling tension: 68.6 MPa

Rolling Rate: 25% of each pass (58% of total rolling rate)

Rolled oil concentration: 3 wt%

Liquid condition: 60 ℃, 10ℓ

Stirring Condition: M-type Homo Mixer 9000r / min

Spray amount: 1ℓ / min × 1 each up and down, 100㎪

Atmosphere temperature: 20 ℃

Invention 7 8 9 10 11 12 lubricant Composition (% by weight) (a) A 60 Maintenance B 68 75 79 70 50 Maintenance D E 20 (b) Composite Ester A 20 15 Composite Ester B 10 20 Composite Ester C 20 30 (c) Polymer Compound A Polymer Compound B One One One Polymer Compound C 2 2 Etc Ester A Ester B Ester C Additive A 5 5 5 5 5 5 Additive B One One One One One One Additive C 2 2 2 2 One Additive D Additive E Additive F Additive G One One One One One One Additive H 3 One One Kinematic viscosity (mm2 / s, 40 ° C) 45 45 40 57 54 65 Iodine (I ₂ g / 100 g) 26 24 22 26 36 30 Melting Point (℃) (Rising Method) 24 25 26 24 20 23 Rolling oil properties Test Example 3 Lubricity (tonf / m) 560 555 560 550 550 540 Alkali Degreasing (%) 100 100 100 100 90 95 Test Example 4 Sescum resistance (g) 26 14 18 14 12 13 Particle Size Stability 2 One 0 One 0 One

Comparative product 7 8 9 10 11 12 lubricant Composition (% by weight) (a) A Maintenance B 90 70 Maintenance D 98 E 70 30 (b) Composite Ester A Composite Ester B 20 38 Composite Ester C (c) Polymer Compound A Polymer Compound B One One Polymer Compound C 2 2 Etc Ester A 19 Ester B 20 74 Ester C 15 Additive A 5 5 5 3 6 Additive B One One One 2 Additive C 2 2 Additive D 2 Additive E 2 Additive F One Additive G One One One One Additive H 2 One One 3 One Kinematic viscosity (mm2 / s, 40 ° C) 43 28 34 72 70 75 Iodine (I ₂ g / 100 g) 49 18 30 59 56 65 Melting Point (℃) (Rising Method) 40 28 22 12 0 12 Rolling oil properties Test Example 3 Lubricity (tonf / m) 600 660 660 550 600 545 Alkali Degreasing (%) 60 100 95 30 40 20 Test Example 4 Sescum resistance (g) 56 20 14 11 28 11 Particle Size Stability 5 0 One One 2 One

Holding E. Palm oil (iodine viscosity of 65 mm, melting point of 8 ° C., 40 ° C., 41 mm 2 / sec, proportion of fatty acids having 12 to 14 carbon atoms in constituent fatty acids 1% by weight)

Ester A... 2 ethylhexyl stearate

Ester B... Ester obtained from trimethylolpropane / oleic acid / stearic acid = 14.4 / 60.0 / 25.6 (weight ratio) (acid value 5)

Ester C... Ester obtained from pentaerythritol / oleic acid / stearic acid = 14.4 / 60.0 / 25.6 (weight ratio) (acid value 5)

Additive F. Antioxidant (phenyl-α-naphthylamine)

Additive G... Antirust agent (hexadecenyl succinic acid)

Additive H... Emulsifier (polyoxyethylene nonylphenyl ether, HLB = 12.4)

As is clear from the results shown in Tables 3 and 4, the cold rolled oil for circulating supply of the present invention is superior in both lubricity and degreasing properties as compared with the comparative product. In particular, it is excellent in all the performances compared with the conventional tallow cold rolling oil of the comparative product 7.

Claims (10)

The grease for steel plate cold rolling oil containing (a) the fats and oils which have a C12-14 fatty acid 50 weight% or more among the fatty acids which comprise fats and oils, and (b) a composite ester. The lubricant for steel sheet cold rolled oil according to claim 1, wherein the proportion of fatty acids having 8 or less carbon atoms is 5% by weight or less among the fatty acids constituting the fat or oil. The lubricant for steel sheet cold rolled oil according to claim 1 or 2, wherein (b) is an ester obtained from a polybasic acid, a polyhydric alcohol, and a monohydric alcohol and / or a monovalent fatty acid. The residual carboxyl group or hydroxyl group of the partial ester obtained from at least one selected from the group consisting of dimer acid and polymer acid of higher aliphatic unsaturated acids having 16 to 20 carbon atoms and polyols according to claim 1 or 2; The lubricating oil for steel plate cold rolling oil which is esterified by the monohydric alcohol or monovalent fatty acid of 12-22 carbon atoms, and is ester of a weight average molecular weight 750-20000. (C) (c1) A homopolymer of the monomer represented by formula (1) or a salt thereof, (c2) two or more copolymers of this monomer, and (c3) one of these monomers. 1 type of water-soluble high molecular compound which is a polymer selected from the copolymer of the above and (meth) acrylic acid, its salt, its alkyl ester, or its alkylamide, and whose weight average molecular weight is 10000-1 million. Lubricating oil for steel plate cold rolling oil containing the above. [Formula 1] (Wherein R ¹ represents a hydrogen atom or a methyl group, R ² and R ³ represent an alkyl group of 1 to 3 carbon atoms, A represents -O- or -NH-, and m represents an integer of 1 to 3) The steel plate cold rolling oil containing the lubricating oil and water of Claim 1 or 5. 7. The cold rolled steel sheet of claim 6, which is for direct supply. 7. The steel sheet cold rolled oil according to claim 6, which is for circulation feeding. The method of cold rolling a steel plate using the steel plate cold rolling oil containing the lubricating oil and water of Claim 1 or 5. The use of the lubricating oil of Claim 1 or 5 as a lubricating oil for steel plate cold rolling oil.