JP2014084428A - Lubricant for a polycarbonate resin - Google Patents

Abstract

Disclosed is a polycarbonate resin composition that is suppressed in coloring and excellent in releasability, heat resistance, and moldability, a lubricant used in the resin composition, and a molded product comprising the resin composition.
A lubricant containing pentaerythritol tetrafatty acid ester composed of pentaerythritol and a fatty acid containing stearic acid and palmitic acid, the mass of stearic acid and palmitic acid contained in the fatty acid constituting the ester A lubricant for a polycarbonate resin, wherein the ratio (stearic acid / palmitic acid) is 0.5 to 1.2, and the contents of the metal elements Na and Sn in the lubricant are each 2 mg / kg or less, (a) polycarbonate A resin, and (b) a resin composition containing the lubricant, and a molded product formed by molding the resin composition.
[Selection figure] None

Description

  The present invention relates to a lubricant for polycarbonate resin, a resin composition containing the lubricant, and a molded article.

  Polycarbonate resins are widely used in OA equipment, electrical / electronic equipment, automobile parts, etc. due to their excellent impact resistance, heat resistance, electrical properties, etc., but they have the problems of high molding processing temperature and poor melt flowability. Have.

Polycarbonate resin is molded into various molded products by injection molding, but in the case of parts such as copiers, fax machines and other office equipment, electrical and electronic equipment, housings, etc., if the shape becomes complicated, ribs, bosses, etc. Since the unevenness is formed in the molded product, it may be difficult to remove the molded product from the mold, the mold can not be removed, there is a hole in the molded product, deformation even if it can be removed, Whitening and distortion remain, resulting in problems such as reduction in dimensional accuracy, strength, and appearance of the molded product.
On the other hand, in order to improve the releasability of thermoplastic resins such as polycarbonate resins, adding fatty acid esters is often performed. For example, Patent Documents 1 to 3 disclose polycarbonate resin compositions containing pentaerythritol fatty acid esters as fatty acid esters.

JP 2003-327818 A JP 2004-137423 A JP 2001-192543 A

However, the resin compositions disclosed in Patent Documents 1 to 3 are not satisfactory in terms of releasability, heat resistance, moldability, and hue.
An object of the present invention relates to a polycarbonate resin composition that is suppressed in coloration and excellent in releasability, heat resistance, and moldability, a lubricant used in the resin composition, and a molded article comprising the resin composition.

The present invention includes a lubricant containing a pentaerythritol tetrafatty acid ester having a specific fatty acid composition and having a specific metal element content of a certain amount or less, a polycarbonate resin and a resin composition containing the lubricant, and the resin composition A molded article comprising:
That is, the present invention relates to the following [1] and [2].
[1] A lubricant containing pentaerythritol tetrafatty acid ester composed of pentaerythritol and a fatty acid containing stearic acid and palmitic acid, the mass ratio of stearic acid and palmitic acid contained in the fatty acid constituting the ester A lubricant for polycarbonate resin, wherein (stearic acid / palmitic acid) is 0.5 to 1.2, and the contents of metal elements Na and Sn in the lubricant are each 2 mg / kg or less.
[2] A resin composition comprising (a) a polycarbonate resin, and (b) the lubricant according to [1].
[3] A molded product obtained by molding the resin composition according to [2].

  According to the present invention, it is possible to provide a polycarbonate resin composition that is suppressed in coloration and excellent in releasability, heat resistance, and moldability, a lubricant used in the resin composition, and a molded article comprising the resin composition. Can do.

[Lubricant]
The lubricant of the present invention is a lubricant containing pentaerythritol tetrafatty acid ester composed of pentaerythritol and a fatty acid containing stearic acid and palmitic acid, and includes stearic acid and palmitic acid contained in the fatty acid constituting the ester. The mass ratio (stearic acid / palmitic acid) is 0.5 to 1.2, and the contents of the metal elements Na and Sn in the lubricant are each 2 mg / kg or less.
The lubricant of the present invention is used as a lubricant for polycarbonate resin. When a general lubricant is used for the polycarbonate resin, the heat resistance is likely to decrease, but the use of the lubricant of the present invention can improve the decrease in the heat resistance.
In the present specification, pentaerythritol tetrafatty acid ester may be simply referred to as “ester”.

The mass ratio (stearic acid / palmitic acid) of stearic acid and palmitic acid contained in the fatty acid constituting the ester is 0.5 or more, preferably 0.7 or more, from the viewpoint of moldability and heat resistance. 0.8 or more is more preferable, and from the viewpoint of releasability and heat resistance, it is 1.2 or less, preferably 1.15 or less, and more preferably 1.10 or less. The mass ratio of stearic acid and palmitic acid is 0.5 to 1.2, preferably 0.5 to 1.15, more preferably 0.7 to 1.15, and 0.8 to 1. 10 is more preferable.
Among the fatty acids, the total content of stearic acid and palmitic acid is preferably 95% by mass or more, more preferably 96% by mass or more, from the viewpoints of moldability, heat resistance, and releasability. More preferably, it is 98 mass% or more. The fatty acid may contain a fatty acid other than stearic acid and palmitic acid.
The composition ratio of the fatty acid constituting the ester can achieve the above-mentioned range by adjusting the composition, type, preparation ratio, and the like of the fatty acid used as the ester raw material.
The mass ratio of stearic acid and palmitic acid (stearic acid / palmitic acid) and the total content of stearic acid and palmitic acid in the total fatty acids used as raw materials for the ester are within the range described for the fatty acids constituting the ester. It is preferable that it exists in.
As a fatty acid used for the raw material of the said ester, the fatty acid derived from raw material fats and oils can be used 1 type or in combination of 2 or more types, for example. Examples of raw oils and fats include vegetable oils such as rapeseed oil, sunflower oil, corn oil, soybean oil, rice oil, safflower oil, cottonseed oil and linseed oil, and animal oils such as beef fat, pork fat and fish oil.

The acid value of the ester is preferably 3.0 mgKOH / g or less, more preferably 2.5 mgKOH / g or less, from the viewpoint of impact strength. Although there is no particular lower limit, it is preferably 1.0 mgKOH / g from the economical viewpoint. Here, the acid value is the number of mg of potassium hydroxide required to neutralize free fatty acids and the like contained in 1 g of a sample, and can be determined by the method defined in JIS K 0070-1992.
In order to set the acid value of the ester within the above range, the reaction product is sampled during the esterification reaction described below, the acid value is measured, and the esterification reaction is stopped when the desired acid value is reached. Can be implemented.

  The hydroxyl value of the ester is preferably in the range of 0.1 to 40 mgKOH / g, more preferably in the range of 1 to 30 mgKOH / g, and still more preferably in the range of 2 to 20 mgKOH / g. Here, the hydroxyl value is the number of mg of potassium hydroxide required to neutralize acetic acid bonded to a hydroxyl group when 1 g of a sample is acetylated, and is obtained by the method defined in JIS K 0070-1992. Can do.

The ester is obtained by esterification or transesterification of pentaerythritol with a fatty acid containing stearic acid and palmitic acid or its lower alcohol (C1-3).
As a specific method for producing the ester, an esterification reaction is preferable, and examples thereof include a method of performing an esterification reaction of pentaerythritol and a fatty acid containing stearic acid and palmitic acid in the presence of a catalyst.
Examples of the catalyst used in the esterification reaction include one or more metal catalysts selected from titanium catalysts such as tetraisopropyl titanate, tin catalysts such as tin octylate, dibutyltin oxide, and tin oxide (SnO).
The amount of the catalyst to be used is preferably 0.01 to 0.5% by mass, more preferably 0.02 to 0.1% by mass, based on the total amount of pentaerythritol and the fatty acid.
The charged molar ratio of the fatty acid is preferably 3.5 to 4.5 mol, more preferably 3.7 to 4.2 mol, and still more preferably 3.8 to 4. mol with respect to 1.0 mol of pentaerythritol. 0 mole.
The reaction temperature in the esterification reaction is preferably 180 to 260 ° C, more preferably 190 to 240 ° C.

In the lubricant of the present invention, the ester content is preferably 90% by mass or more, more preferably 95% by mass or more, still more preferably 99% by mass or more, and still more preferably 100%.
Substantially 100% means that the metal elements Na and Sn may be contained in the range of 2 mg / kg or less in addition to the ester.
The content of the metal element Na in the lubricant of the present invention is 2 mg / kg or less, preferably 1.0 mg / kg or less, from the viewpoint of impact strength and releasability, in addition to heat resistance improvement and coloring suppression. More preferably, it is 5 mg / kg or less.
The content of the metal element Sn in the lubricant of the present invention is 2 mg / kg or less, preferably 1.0 mg / kg or less, from the viewpoint of impact strength and releasability, in addition to heat resistance improvement and coloring suppression, More preferably, it is 5 mg / kg or less.
As the lubricant of the present invention, as components other than the ester, metal elements Na and Sn, a pentaerythritol component which is an unreacted component in the production of pentaerythritol tetrafatty acid ester, a stearic acid component, a palmitic acid component, or a pentaerythritol tetra Esters other than fatty acid esters may be contained.
Examples of esters other than pentaerythritol tetrafatty acid ester include dipentaerythritol hexafatty acid ester and trimethylolpropane fatty acid ester.

As a method for reducing the contents of the metal elements Na and Sn contained in the ester, a method of treating with an adsorbent is preferable. When a tin catalyst is used during the production of the ester, an excess of the tin catalyst in the ester is used. A method of treating with an adsorbent after neutralization with phosphoric acid is preferred.
The adsorbent used when adsorbing the ester with the adsorbent is preferably an adsorbent containing magnesium silicate and / or magnesium oxide from the viewpoint of reducing the contents of the metal elements Na and Sn. The adsorbent may contain silicon dioxide, aluminum oxide and the like in addition to the above components.
From the viewpoint of reducing the contents of the metal elements Na and Sn, the total content of magnesium silicate and magnesium oxide in the adsorbent is preferably 25% by mass or more, more preferably 40% by mass or more, and 70% by mass or more. Is more preferable, and 90% by mass or more is more preferable.
The adsorption treatment is performed by mixing the ester and the adsorbent, but the method is not particularly limited, and a method of adding the adsorbent to the ester at once or a method of gradually adding the adsorbent. Etc.

  Specific examples of the adsorbent include Kyoward 300 (magnesium oxide content: 28% by mass, manufactured by Kyowa Chemical Industry Co., Ltd.), Kyoward 600S (magnesium silicate content: 100% by mass, manufactured by Kyowa Chemical Industry Co., Ltd.). ) And the like.

  The addition amount of the adsorbent is preferably 0.1 to 10 parts by mass, more preferably 0.7 to 7 parts by mass, and still more preferably from the viewpoint of cost reduction and adsorption efficiency with respect to 100 parts by mass of the ester. It is 0.8-5 mass parts, More preferably, it is 1-5 mass parts, More preferably, it is 1-3 mass parts.

During the adsorption treatment, the temperature of the object to be adsorbed during the adsorption treatment is preferably 100 ° C. or less from the viewpoint of suppressing coloration, preferably 70 ° C. or more, and preferably 70 to 100 ° C. Preferably it is 70-90 degreeC, More preferably, it is 70-80 degreeC.
Further, the mixing time of the object to be adsorbed and the adsorbent is preferably 5 hours or less from the viewpoint of productivity, preferably 0.5 hours or more from the viewpoint of adsorption removal, and preferably 0.5 to 5 hours, 0 More preferably, 5 to 3 hours.

In the present invention, the lubricant of the present invention can be obtained by removing the adsorbent from the adsorption-treated product obtained as described above by a filtration step or the like. When performing a filtration process, it is preferable to make the temperature of an adsorption treatment thing into 70-80 degreeC before using an adsorption treatment thing for a filtration process from a viewpoint of filtration efficiency and coloring suppression. The filtration step of the adsorbent can be performed under conditions of reduced pressure filtration of preferably 60 kPa or less, more preferably 40 kPa or less, or preferably pressure filtration of 100 to 600 kPa, more preferably 200 to 510 kPa.
At this time, diatomaceous earth, pearlite, or the like may be used as a filter aid to reduce the filtration load.

  In addition, tin ions and sodium ions in the ester can be reduced by an ion exchange resin.

[Resin composition]
The resin composition of the present invention contains a polycarbonate resin as the component (a) and the lubricant of the present invention as the component (b).

(Polycarbonate resin)
As the polycarbonate resin, an aromatic polycarbonate produced by a reaction between a dihydric phenol and a carbonate precursor is preferable. The reaction between the dihydric phenol and the carbonate precursor includes a solution method or a melting method. Specific examples include a reaction between the dihydric phenol and phosgene and a transesterification reaction between the dihydric phenol and diphenyl carbonate.

  Divalent phenols include 2,2-bis (4-hydroxyphenyl) propane [bisphenol A], bis (4-hydroxyphenyl) methane, 1,1-bis (4-hydroxyphenyl) ethane, and 2,2-bis. (4-hydroxy-3,5-dimethylphenyl) propane, 4,4′-dihydroxydiphenyl, bis (4-hydroxyphenyl) cycloalkane, bis (4-hydroxyphenyl) oxide, bis (4-hydroxyphenyl) sulfide, Bis (4-hydroxyphenyl) sulfone, bis (4-hydroxyphenyl) sulfoxide, bis (4-hydroxyphenyl) ether, bis (4-hydroxyphenyl) ketone and the like can be mentioned. In addition, examples of the dihydric phenol include hydroquinone, resorcin, and catechol. These dihydric phenols may be used alone or in admixture of two or more. Particularly preferred dihydric phenols are those based on bis (hydroxyphenyl) alkanes, particularly bisphenol A.

  Examples of the carbonate precursor include carbonyl halide, carbonyl ester, haloformate and the like, and specifically, phosgene, dihaloformate of dihydric phenol, diphenyl carbonate, dimethyl carbonate, diethyl carbonate and the like.

  The polycarbonate resin may have a branched structure, and 1,1,1-tris (4-hydroxyphenyl) ethane, α, α ′, α ″ -tris (4-hydroxy) may be used as the branching agent. Phenyl) -1,3,5-triisopropylbenzene, phloroglycine, trimellitic acid, isatin bis (o-cresol) and the like. Moreover, phenol, pt-butylphenol, pt-octylphenol, p-cumylphenol, etc. are used for adjustment of molecular weight.

  Further, as the polycarbonate resin, a copolymer having a polycarbonate part and a polyorganosiloxane part, or a polycarbonate resin containing this copolymer can also be used. Further, the copolymer may be a polyester-polycarbonate resin obtained by conducting a polymerization reaction of polycarbonate in the presence of an ester precursor such as a bifunctional carboxylic acid such as terephthalic acid or an ester-forming derivative thereof. . Furthermore, various polycarbonate resins can be used by mixing them appropriately.

The polycarbonate resin preferably has a viscosity average molecular weight of 10,000 to 100,000, particularly preferably 14,000 to 40,000, from the viewpoint of mechanical strength and moldability. The viscosity average molecular weight (Mv) of the polycarbonate resin is obtained by measuring the viscosity of the methylene chloride solution at 20 ° C. using an Ubbelohde viscometer, obtaining the intrinsic viscosity “η” from this, and calculating by the following equation. .
“Η” = 1.23 × 10 ⁻⁵ Mv ^0.83

  In the resin composition of the present invention, the content of the lubricant as the component (b) with respect to 100 parts by mass of the polycarbonate resin (a) is the moldability, the release property at the time of injection molding, the bleed prevention property of the lubricant, and the Izod impact strength. In view of the above, 0.6 parts by mass or more is preferable, 0.8 parts by mass or more is more preferable, and from the economical aspect, 5.0 parts by mass or less is preferable, and 2.0 parts by mass or less is more preferable. . Moreover, 0.6-5.0 mass parts is preferable and, as for the content rate of (b) component with respect to 100 mass parts of (a) component, 0.8-2.0 mass parts is more preferable.

  In the resin composition of the present invention, other additives usually used in thermoplastic resins for the purpose of improving the appearance, preventing static charge, improving weather resistance, improving rigidity and the like can be appropriately blended as necessary. As for content of an additive, 5 mass parts or less are preferable with respect to 100 mass parts of (a) polycarbonate resin.

  The resin composition of the present invention can be obtained by blending the components (a) and (b) and other additives in an appropriate ratio and kneading. The compounding and kneading at this time are premixed with a commonly used equipment such as a ribbon blender or a drum tumbler, and then a Henschel mixer, a Banbury mixer, a single screw extruder, a twin screw extruder, a multi screw extruder. It can be performed by a method using a machine, a conida or the like. The heating temperature at the time of kneading is usually appropriately selected within the range of 240 to 300 ° C. It should be noted that the components other than the component (a) can be added as a master batch which is previously melt-kneaded with the component (a).

The resin composition of the present invention is a pellet obtained by the melt kneading molding method, or using this pellet as a raw material, an injection molding method, an injection compression molding method, an extrusion molding method, a blow molding method, a press molding method, a vacuum, It can be produced as various molded products by a molding method, a foam molding method, or the like. Among them, a pellet-shaped molding raw material is manufactured by the melt-kneading molding method, and then, using this pellet, it is particularly suitable for manufacturing an injection molded product by injection molding or injection compression molding in which mold release properties are most problematic. Can be used. As the injection molding method, a gas injection molding method can be employed for preventing the appearance of sink marks or reducing the weight.
The molded product of the present invention is obtained by molding the resin composition by such a method.

  Molded products (including injection molded products and injection compression molded products) obtained from the resin composition of the present invention include copiers, fax machines, televisions, radios, tape recorders, video decks, personal computers, printers, telephones, information terminals OA equipment such as refrigerators and microwave ovens, home appliances, housings and various parts of electric / electronic devices

The physical properties of the ester and lubricant were measured and evaluated by the following methods.
(1) Fatty acid composition of ester Obtained by preparing fatty acid methyl ester according to “Preparation method of fatty acid methyl ester (2.4.1.-1996)” in “Standard oil analysis test method” edited by Japan Oil Chemists' Society Samples were measured by American Oil Chemists. Society Official Method Ce 1f-96 (GLC method).

(2) Acid value measurement method 20 g of a sample was weighed correctly into an Erlenmeyer flask, a 1% phenolphthalein indicator solution was added to a toluene-ethanol mixture (2: 1), and a mixed solvent neutralized to a slight red color just before use. And dissolved, and titrated with a 0.1 mol / L alcoholic potassium hydroxide standard solution. The end point is a point where a slight red color lasts for 30 seconds.
The acid value is determined from the following formula. Acid value = (A × f × K) / sampled amount (g)
A: Amount of alcoholic potassium hydroxide standard solution required for titration (mL)
f: Factor of alcoholic potassium hydroxide standard solution
K: 5.611

(3) Method for Measuring Hydroxyl Value Analysis is performed according to the test method of JIS K 0070-1992 except that acetic anhydride / pyridine = 1/4 (volume ratio) is used as the acetylating reagent and the addition amount is 3 mL.

(4) Method for measuring content of metal element Quantitative analysis by inductively coupled plasma optical emission spectrometry (ICP-AES) is performed using SPS5100 type manufactured by SII Nano Technology Co., Ltd. The Sn content was measured.

Each performance of the resin composition was measured and evaluated by the following methods.
(1) Izod impact strength Impact strength (unit: kJ / unit) at a measurement temperature of 23 ° C. according to ASTM standard D-255 using a 3.2 mm (1/8 inch) thick test piece produced by an injection molding machine. m ² ) was measured. Larger values indicate better impact strength.

(2) Formability (melt index)
The melt index (unit: g) was measured using G-01 manufactured by Toyo Seiki Seisakusho under the conditions of 280 ° C. and 2.16 kg load. Larger values indicate better moldability.

(3) Releasability Using a molded product mold (80 mm × 100 mm × thickness 3 mm, draft 0) for the releasability evaluation test, the pressure (unit: unit) at the time of mold release from the mold MPa). The maximum pressure is 2.9 MPa, and the smaller the value, the better the releasability.

(4) Hue The YI value of the test piece used in the evaluation of releasability was measured with a color meter (manufactured by Nippon Denshoku Industries Co., Ltd.). The smaller the value, the better the hue.

(5) Izod impact test after heating The specimen was heat-treated at 140 ° C. for 100 hours and then left at room temperature of 23 ° C. for 24 hours. With respect to the test piece after standing, the impact strength (unit: kJ / m ² ) was measured according to ASTM standard D-255 at a test piece thickness of 3.2 mm (1/8 inch) and a measurement temperature of 23 ° C.
(6) Heat resistance Heat resistance is the ratio of the Izod impact strength after heating measured in (5) above the Izod impact strength before heating measured in (1) above (Izod impact strength after heating / Izod impact strength before heating). ) Was calculated. A value closer to 1 indicates better heat resistance.

Production Example 1
In a 1 L four-necked flask, 81.6 g (0.6 mol) of pentaerythritol (Guangei Chemical Co., Ltd.) and “Lunac P-95” as a fatty acid (trade name, palmitic acid content: 96 mass by Kao Corporation) %, Stearic acid content: 4% by mass) 35.6 g (0.139 mol) and “Lunac S-50V” (trade name, manufactured by Kao Corporation, stearic acid content 55% by mass, palmitic acid content 44% by mass ) 588.6 g (2.172 mol) and 0.21 g of tin oxide (SnO) (reagent) as a catalyst are weighed and heated to 240 ° C. under nitrogen blowing, so that the acid value becomes 2.5 mgKOH / g or less. The esterification reaction was carried out.
Then, it cooled to 70-80 degreeC, added 0.54g of 85 mass% phosphoric acid, and continued stirring for 30 minutes or more. Further, 3.1 g of an adsorbent (trade name: KYOWARD 600S, manufactured by Kyowa Chemical Industry Co., Ltd., magnesium silicate content: 100% by mass) was added and stirred at 75 ° C. for 30 minutes, and then a filter aid (trade name: Radiolite # 700 (manufactured by Showa Chemical Industry Co., Ltd.) was subjected to vacuum filtration at 1 to 3 kPa using an appropriate amount to obtain an ester.
The obtained ester has a [stearic acid / palmitic acid] mass ratio of 1.1 / 1.0, an acid value of 2.2, a hydroxyl value of 8.9, and a content of the metal elements Na and Sn of 2 mg / kg, respectively. It was the following.

Production Example 2
In a 1 L four-necked flask, 81.6 g (0.6 mol) of pentaerythritol (Guangei Chemical Industry Co., Ltd.) and “purified stearic acid 450V” (trade name of Kao Corporation, stearic acid content 45% by mass as fatty acid) , Palmitic acid content 54 mass%) 619.1 g (2.31 mol) and tin oxide (SnO) (reagent) 0.21 g as a catalyst were weighed, and an ester was obtained under the same conditions as in Production Example 1.
The obtained ester has a [stearic acid / palmitic acid] mass ratio of 0.82 / 1.0, an acid value of 2.0, a hydroxyl value of 3.2, and a content of each of the metal elements Na and Sn of 2 mg / kg. It was the following.

Comparative production example 1
In a 1 L four-necked flask, 81.6 g (0.6 mol) of pentaerythritol (manufactured by Guangei Chemical Industry Co., Ltd.) and 35.6 g (0.139 mol) of “Lunac P-95” (trade name, manufactured by Kao Corporation) as a fatty acid ) And “Lunac S-50V” (trade name, manufactured by Kao Corporation) 588.6 g (2.172 mol), 0.21 g of tin oxide (SnO) (reagent) as a catalyst, and up to 240 ° C. under nitrogen blowing The temperature was raised, and the esterification reaction was carried out until the acid value was 2.5 mgKOH / g or less. Then, it cooled to 70-80 degreeC, vacuum filtration was performed at 1-3 kPa using the filter aid (brand name: Radiolite # 700, Showa Chemical Industry Co., Ltd.) suitable amount, and ester was obtained.
The obtained ester has a [stearic acid / palmitic acid] mass ratio of 1.1 / 1.0, an acid value of 2.1, a hydroxyl value of 4.8, a content of metal element Na of 25 mg / g, and a metal element. The Sn content was 280 mg / g.

Comparative production example 2
In a 2 L four-necked flask, 163.2 g (1.2 mol) of pentaerythritol (manufactured by Guangei Chemical Industry Co., Ltd.) and “purified stearic acid 450V” (trade name, manufactured by Kao Corporation) as fatty acid 1238.2 g (4.62 mol) ), 0.42 g of tin oxide (SnO) (reagent) was weighed as a catalyst, and an ester was obtained under the same conditions as in Production Example 1.
To 1300 g of this ester, 75 mg of tin stearate (manufactured by Wako Pure Chemical Industries, Ltd.) was added and dissolved by stirring at 80 to 90 ° C.
The resulting ester has a [stearic acid / palmitic acid] mass ratio of 0.82 / 1.0, an acid value of 2.0, a hydroxyl value of 5.1, a metal element Na content of 2 mg / kg or less, a metal The content of elemental Sn was 10 mg / kg.

Comparative production example 3
In a 2 L four-necked flask, 163.2 g (1.2 mol) of pentaerythritol (manufactured by Koei Chemical Co., Ltd.), stearic acid (trade name: purified stearic acid 450 V, manufactured by Kao Corporation), 1238.2 g (4.62 mol) ), 0.42 g of tin oxide (SnO) (reagent) was weighed as a catalyst, and an ester was obtained under the same conditions as in Production Example 1.
To 1300 g of this ester, 75 mg of tin stearate (manufactured by Wako Pure Chemical Industries, Ltd.) and 180 mg of semi-cured beef tallow fatty acid soda soap (trade name: NS soap, manufactured by Kao Corporation) were added and dissolved by stirring at 80 to 90 ° C. .
The resulting ester has a [stearic acid / palmitic acid] mass ratio of 0.82 / 1.0, an acid value of 1.9, a hydroxyl value of 7.4, a metal element Na content of 10 mg / kg, and a metal element. The Sn content was 10 mg / kg.

Comparative production example 4
In a 1 L four-necked flask, 81.6 g (0.6 mol) of pentaerythritol (manufactured by Guangei Chemical Industry Co., Ltd.), stearic acid (trade name: LUNAC S-50V, stearic acid content 55% by mass, palmitic acid content 44 mass%, manufactured by Kao Corporation) 597.0 g (2.20 mol), stearic acid (trade name: LUNAC S-90V, stearic acid content 96 mass%, palmitic acid content 3 mass%, manufactured by Kao Corporation 30.6 g (0.11 mol) and 0.14 g of tin oxide (SnO) (reagent) as a catalyst were weighed, and an ester was obtained under the same conditions as in Production Example 1.
The resulting ester has a [stearic acid / palmitic acid] mass ratio of 1.4 / 1.0, an acid value of 1.8, a hydroxyl value of 9.5, and metal elements Na and Sn content of 2 mg / kg, respectively. It was the following.

Comparative Production Example 5
In a 1 L four-necked flask, 57.9 g (0.42 mol) of pentaerythritol (manufactured by Guangei Chemical Industry Co., Ltd.), palmitic acid (trade name: LUNAC P-95, palmitic acid content 96 mass%, stearic acid content 42.2% by mass, manufactured by Kao Corporation) 372.2 g (1.51 mol), 0.09 g of tin oxide (SnO) (reagent) as a catalyst was weighed and esterified until the acid value was 2.5 mgKOH / g or less Esters were obtained under the same conditions as in Production Example 1 except that the reaction was performed.
The obtained ester has a [stearic acid / palmitic acid] mass ratio of 0.04 / 1.00, an acid value of 2.3, a hydroxyl value of 10.8, and the contents of the metal elements Na and Sn are 2 mg / kg, respectively. It was the following.

Examples 1-2 and Comparative Examples 1-6
[Production of resin composition]
Using the following components (a) and (b), each component is supplied to an extruder (laboplast mill twin screw extruder, manufactured by Toyo Seiki Seisakusho Co., Ltd.) at the ratio shown in Table 1, and melt mixed at 260 ° C. Smelted and pelletized. In all Examples and Comparative Examples, 0.2 parts by mass of Irganox 1078 (manufactured by BASF Japan) and 0.1 part by mass of ADK STAB C (manufactured by ADEKA) were blended as antioxidants.
The obtained pellets were dried at 80 ° C. for 12 hours and then injection molded at a molding temperature of 260 ° C. to prepare test pieces.
Using the obtained test piece, Izod impact strength and melt index were measured.
Moreover, the YI value was measured using the said mold and the mold release property and the test piece obtained by it.
Table 1 shows the physical properties and evaluation of the resin compositions obtained in each Example and Comparative Example.

(A) Component: Bisphenol A polycarbonate resin (trade name: Toughlon A1900, manufactured by Idemitsu Kosan Co., Ltd.) Melt index: 20 g / 10 min (280 ° C., 2.16 kg load) Viscosity average molecular weight: 19000

(B) Component:
(B-1): Pentaerythritol tetrafatty acid ester of Production Example 1 (b-2): Pentaerythritol tetrafatty acid ester of Production Example 2 (b-3): Pentaerythritol tetrafatty acid ester of Comparative Production Example 1 (b-4) ): Pentaerythritol tetrafatty acid ester (b-5) of Comparative Production Example 2: Pentaerythritol tetrafatty acid ester (b-6) of Comparative Production Example 3: Pentaerythritol tetrafatty acid ester (b-7) of Comparative Production Example 4: Pentaerythritol tetrafatty acid ester (b-8) of Comparative Production Example 5: Pentaerythritol tetrafatty acid ester (trade name: Riquester EW-400, manufactured by Riken Vitamin Co., Ltd., [Stearic acid / palmitic acid] mass ratio = 1.4 / 1.0, acid value is 10.5, hydroxyl value is 2.3, Na content is 2 mg / kg, Sn content is 360 mg / kg)

  From Table 1, the resin composition of Example 1 and 2 is excellent in mold release property, heat resistance, and moldability compared with the resin composition of Comparative Examples 1-6 by containing the lubricant which belongs to this invention. It can be seen that since the coloring is suppressed, the hue is excellent.

  Since the lubricant and the polycarbonate resin composition of the present invention are suppressed in coloring and are excellent in releasability, heat resistance, and moldability, components and housings such as copiers, fax machines and other office equipment, electrical / electronic equipment, etc. It can be widely used for automobile parts and the like.

Claims (6)

  A lubricant containing pentaerythritol tetrafatty acid ester composed of pentaerythritol and a fatty acid containing stearic acid and palmitic acid, the mass ratio of stearic acid and palmitic acid contained in the fatty acid constituting the ester (stearic acid / Palmitic acid) is 0.5 to 1.2, and the content of the metal elements Na and Sn in the lubricant is 2 mg / kg or less, respectively.   The lubricant according to claim 1, wherein the total content of stearic acid and palmitic acid among the fatty acids constituting the ester is 95% by mass or more.   The lubricant according to claim 1 or 2, wherein the acid value of the ester is 3.0 mgKOH / g or less.   A resin composition comprising (a) a polycarbonate resin, and (b) the lubricant according to any one of claims 1 to 3.   (A) The resin composition of Claim 4 which contains 0.6-5.0 mass parts of (b) lubricants with respect to 100 mass parts of polycarbonate resin.   A molded product obtained by molding the resin composition according to claim 4 or 5.