JP2017048369A - Aromatic polycarbonate resin composition and molded article thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an aromatic polycarbonate resin composition which is excellent in residence heat stability, and suppresses reduction in molecular weight and yellow discoloration due to residence on a high temperature condition.SOLUTION: An aromatic polycarbonate resin composition contains an aromatic polycarbonate resin (A), and a stabilizer (B) which includes 0.005-0.1 pt.mass of a phenol-based stabilizer (B-1) having a spiro ring skeleton and 0.005-0.1 pt.mass of a phosphite-based stabiliser (B-2) having a spiro ring skeleton, with respect to 100 pts.mass of the aromatic polycarbonate resin (A).SELECTED DRAWING: None

Description

  The present invention relates to an aromatic polycarbonate resin composition. Specifically, the present invention relates to an aromatic polycarbonate resin composition having improved residence heat stability. The present invention also relates to a molded article formed by molding this aromatic polycarbonate resin composition.

  Aromatic polycarbonate resins are excellent in impact resistance, heat distortion resistance, rigidity, dimensional stability, transparency, etc., and are therefore used in a wide range of applications such as electrical equipment, communication equipment, precision machinery, and automotive parts.

  Aromatic polycarbonate resin deteriorates by receiving heat during the molding process, causing problems such as molecular weight reduction and yellowing due to decomposition of the resin. The decrease in the molecular weight of the aromatic polycarbonate resin impairs the mechanical properties such as the excellent impact resistance inherent in the aromatic polycarbonate resin, and yellowing is a product for applications that utilize the transparency inherent in the aromatic polycarbonate resin. It becomes a serious problem that damages value.

  On the other hand, for example, when injection molding an aromatic polycarbonate resin composition, it is possible to ensure a long holding time from filling the aromatic polycarbonate resin composition into the cylinder of the injection molding machine until the molten resin is injected, Residual heat stability of the resin composition is very important in industrial production. For example, the degree of freedom in production planning (molding cycle) can be increased, and unexpected troubles can be dealt with. This is an improvement item.

  Conventionally, in order to improve the residence heat stability of an aromatic polycarbonate resin composition, a heat stabilizer has been blended. For example, Patent Document 1 discloses a phosphorous having a spiro ring skeleton as a heat stabilizer. It is described that yellowing is suppressed by adding a phyto-based stabilizer.

JP2013-139097A

  If it is the aromatic polycarbonate resin composition of patent document 1, a certain amount of yellowing suppression effect will be acquired, but it is not enough, and the improvement of further residence heat stability is desired.

  An object of the present invention is to provide an aromatic polycarbonate resin composition excellent in staying heat stability and suppressed in molecular weight reduction and yellowing due to staying under high temperature conditions, and a molded product thereof.

  In order to solve the above-mentioned problems, the present inventor has conducted extensive research on a heat stabilizer to be blended with an aromatic polycarbonate resin. It has been found that the above-mentioned problems can be solved by using together.

  The present invention has been achieved based on such findings, and the gist thereof is as follows.

[1] With respect to 100 parts by mass of the aromatic polycarbonate resin (A) and the aromatic polycarbonate resin (A), as a stabilizer (B), a phenol-based stabilizer (B-1) 0.005 having a spiro ring skeleton. An aromatic polycarbonate resin composition comprising: -0.1 part by mass and 0.005-0.1 part by mass of a phosphite stabilizer (B-2) having a spiro ring skeleton.

[2] In [1], the phenol stabilizer (B-1) having a spiro ring skeleton has a 2,4,8,10-tetraoxaspiro [5.5] undecane ring, Group polycarbonate resin composition.

[3] An aromatic polycarbonate resin composition characterized in that, in [1] or [2], the phosphite stabilizer (B-2) having a spiro ring skeleton is represented by the following general formula (II).

(In formula (II), R ^10A and R ^10B each independently represent an alkyl group having 1 to 30 carbon atoms or an aryl group having 6 to 30 carbon atoms.)

[4] In any one of [1] to [3], the weight ratio of the phenol-based stabilizer (B-1) having a spiro ring skeleton and the phosphite stabilizer (B-2) having a spiro ring skeleton. Is a phenol-based stabilizer having a spiro-ring skeleton (B-1): a phosphite-based stabilizer having a spiro-ring skeleton (B-2) = 1: 0.5-2, and a phenol-based having a spiro-ring skeleton The total content of the stabilizer (B-1) and the phosphite stabilizer (B-2) having a spiro ring skeleton is 0.01 to 0.15 with respect to 100 parts by mass of the aromatic polycarbonate resin (A). An aromatic polycarbonate resin composition characterized by being part by mass.

[5] In any one of [1] to [4], the YI value measured for a molded article having a thickness of 2 mm obtained by injection molding after holding the pellet of the aromatic polycarbonate resin composition at 340 ° C. for 5 minutes. Is YI (5), and the YI value measured for a molded article having a thickness of 2 mm obtained by injection molding after holding the pellet of the aromatic polycarbonate resin composition at 340 ° C. for 20 minutes is defined as YI (20) An aromatic polycarbonate resin composition, wherein the increase amount ΔYI of the YI value calculated by the following formula (1) is 0.3 or less.
ΔYI = YI (20) −YI (5) (1)

[6] In any one of [1] to [5], the viscosity average molecular weight of the aromatic polycarbonate resin (A) contained in the aromatic polycarbonate resin composition pellet is Mv (0), and the aromatic polycarbonate resin composition When the viscosity average molecular weight of the aromatic polycarbonate resin (A) contained in the molded article obtained by holding the pellet at 340 ° C. for 20 minutes and then injection molding is Mv (20), it is calculated by the following formula (2). An aromatic polycarbonate resin composition having a decrease in viscosity average molecular weight ΔMv of 1000 or less.
ΔMv = Mv (0) −Mv (20) (2)

[7] A molded product formed by molding the aromatic polycarbonate resin composition according to any one of [1] to [6].

[8] The molded article according to [7], which is an automotive lighting cover.

The aromatic polycarbonate resin composition of the present invention is excellent in residence heat stability and has almost no problem of molecular weight reduction or yellowing due to residence under high temperature conditions.
For this reason, according to the aromatic polycarbonate resin composition of the present invention, for example, in the production of a molded product by injection molding, it is possible to increase the degree of freedom of the molding cycle, and it is efficient to flexibly respond to the situation of the production line. It becomes possible to perform proper molding.

  The molded article of the aromatic polycarbonate resin composition of the present invention is useful for a wide range of applications such as electrical equipment, communication equipment, precision machinery, automobile parts, etc., but the aromatic polycarbonate resin composition of the present invention is stable in residence heat stability. Excellent, even when the residence time in the molding machine is long during molding, there are few problems of molecular weight reduction and yellowing due to resin decomposition, and it is possible to obtain molded products with excellent mechanical properties such as impact resistance and hue Therefore, the molded product formed by molding the aromatic polycarbonate resin composition of the present invention is particularly suitable in the fields of mechanical properties such as impact resistance and transparency, and the lens cover, lighting cover, etc. where the hue is important. used. The molded article made of the aromatic polycarbonate resin composition of the present invention is particularly suitably used as an automotive lighting cover.

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

[Aromatic polycarbonate resin composition]
The aromatic polycarbonate resin composition of the present invention comprises an aromatic polycarbonate resin (A) and a phenolic stabilizer having a spiro ring skeleton as a stabilizer (B) with respect to 100 parts by mass of the aromatic polycarbonate resin (A). It contains 0.005 to 0.1 parts by mass of (B-1) and 0.005 to 0.1 parts by mass of a phosphite stabilizer (B-2) having a spiro ring skeleton.

[Aromatic polycarbonate resin (A)]
The aromatic polycarbonate resin (A) is an aromatic polycarbonate polymer obtained by reacting an aromatic hydroxy compound with a diester of phosgene or carbonic acid. The aromatic polycarbonate polymer may have a branch. The method for producing the aromatic polycarbonate resin is not particularly limited, and may be a conventional method such as a phosgene method (interfacial polymerization method) or a melting method (transesterification method).

  Typical examples of the aromatic dihydroxy compound include bis (4-hydroxyphenyl) methane, 2,2-bis (4-hydroxyphenyl) propane, and 2,2-bis (4-hydroxy-3-methylphenyl). ) Propane, 2,2-bis (4-hydroxy-3-tert-butylphenyl) propane, 2,2-bis (4-hydroxy-3,5-dimethylphenyl) propane, 2,2-bis (4-hydroxy) -3,5-dibromophenyl) propane, 4,4-bis (4-hydroxyphenyl) heptane, 1,1-bis (4-hydroxyphenyl) cyclohexane, 4,4'-dihydroxybiphenyl, 3,3 ', 5 , 5′-tetramethyl-4,4′-dihydroxybiphenyl, bis (4-hydroxyphenyl) sulfone, bis (4-hydroxyphenyl) Le) sulfide, bis (4-hydroxyphenyl) ether, bis (4-hydroxyphenyl) ketone.

Among the aromatic dihydroxy compounds, 2,2-bis (4-hydroxyphenyl) propane (bisphenol A) is particularly preferable.
The aromatic dihydroxy compounds may be used alone or in combination of two or more.

  When the aromatic polycarbonate resin (A) is produced, a small amount of polyhydric phenol having 3 or more hydroxy groups in the molecule may be added in addition to the aromatic dihydroxy compound. In this case, the aromatic polycarbonate resin (A) has a branch.

  Examples of the polyhydric phenol having three or more hydroxy groups include phloroglucin, 4,6-dimethyl-2,4,6-tris (4-hydroxyphenyl) heptene-2, 4,6-dimethyl-2,4. , 6-tris (4-hydroxyphenyl) heptane, 2,6-dimethyl-2,4,6-tris (4-hydroxyphenyl) heptene-3, 1,3,5-tris (4-hydroxyphenyl) benzene, Polyhydroxy compounds such as 1,1,1-tris (4-hydroxyphenyl) ethane, or 3,3-bis (4-hydroxyaryl) oxindole (= isatin bisphenol), 5-chlorouisatin, 5,7-dichloroisatin , 5-bromoisatin and the like. Among these, 1,1,1-tris (4-hydroxylphenyl) ethane or 1,3,5-tris (4-hydroxyphenyl) benzene is preferable. The amount of the polyhydric phenol used is preferably an amount of 0.01 to 10 mol%, more preferably 0.1 to 2 mol%, based on the aromatic dihydroxy compound (100 mol%). It is.

  In the polymerization by the transesterification method, a carbonic acid diester is used as a monomer instead of phosgene. Representative examples of the carbonic acid diester include substituted diaryl carbonates typified by diphenyl carbonate and ditolyl carbonate, and dialkyl carbonates typified by dimethyl carbonate, diethyl carbonate, di-tert-butyl carbonate and the like. These carbonic acid diesters can be used alone or in combination of two or more. Among these, diphenyl carbonate and substituted diphenyl carbonate are preferable.

  The carbonic acid diester may preferably be substituted with dicarboxylic acid or dicarboxylic acid ester in an amount of 50 mol% or less, more preferably 30 mol% or less. Representative dicarboxylic acids or dicarboxylic acid esters include terephthalic acid, isophthalic acid, diphenyl terephthalate, and diphenyl isophthalate. When a part of the carbonic acid diester is substituted with such a dicarboxylic acid or dicarboxylic acid ester, a polyester carbonate is obtained.

  When an aromatic polycarbonate resin is produced by a transesterification method, a catalyst is usually used. Although there is no restriction | limiting in a catalyst seed | species, Generally basic compounds, such as an alkali metal compound, an alkaline-earth metal compound, a basic boron compound, a basic phosphorus compound, a basic ammonium compound, an amine compound, are used. Of these, alkali metal compounds and / or alkaline earth metal compounds are particularly preferred. These may be used alone or in combination of two or more. In the transesterification method, the catalyst is generally deactivated with p-toluenesulfonic acid ester or the like.

  The aromatic polycarbonate resin (A) can be copolymerized with a polymer or oligomer having a siloxane structure for the purpose of imparting flame retardancy and the like.

The viscosity average molecular weight of the aromatic polycarbonate resin (A) is preferably 15,000 to 30,000. When the viscosity average molecular weight of the aromatic polycarbonate resin (A) is less than 15,000, the obtained molded article has insufficient mechanical strength, and it may not be possible to obtain a product having sufficient mechanical strength. Further, when the viscosity average molecular weight of the aromatic polycarbonate resin (A) exceeds 30,000, the melt viscosity of the aromatic polycarbonate resin (A) becomes large. For example, the aromatic polycarbonate resin composition is molded by injection molding. When it is not possible to obtain excellent fluidity when manufacturing the resin, and the amount of heat generated by shearing of the resin increases and the resin deteriorates due to thermal decomposition, so that a molded product having an excellent hue cannot be obtained. There is.
The viscosity average molecular weight of the aromatic polycarbonate resin (A) is more preferably 17,000 to 28,000, and further preferably 18,000 to 25,000.

  Here, the viscosity average molecular weight is calculated from the solution viscosity measured at a temperature of 20 ° C. using methylene chloride as a solvent.

  The aromatic polycarbonate resin (A) may be a mixture of two or more kinds of aromatic polycarbonate resins having different viscosity average molecular weights, or a mixture of aromatic polycarbonate resins having a viscosity average molecular weight outside the above range. It may be within the range of the viscosity average molecular weight.

[Stabilizer (B)]
The aromatic polycarbonate resin composition of the present invention includes, as the stabilizer (B), a phenolic stabilizer (B-1) having a spiro ring skeleton (hereinafter sometimes referred to as “component (B-1)”). And a phosphite stabilizer (B-2) having a spiro ring skeleton (hereinafter sometimes referred to as “component (B-2)”).

<Phenolic stabilizer (B-1) having a spiro ring skeleton>
The phenol-based stabilizer (B-1) having a spiro ring skeleton is not particularly limited as long as it is a phenol compound having a spiro ring skeleton, and is represented by the following formula (Ia) as a spiro ring. Those having a 4,8,10-tetraoxaspiro [5.5] undecane ring are preferred, and those represented by the following general formula (I) are particularly preferred.

(In formula (I), R ^1A , R ^1B , R ^3A , R ^3B , R ^4A and R ^4B each independently represents a hydrogen atom or an alkyl group, and R ^5A and R ^5B each independently represent an alkylene. Represents a group.)

In the general formula (I), R ^1A , R ^1B , R ^2A and R ^2B are preferably each independently a linear or branched lower alkyl group having 1 to 4 carbon atoms, particularly preferably a methyl group. It is.
R ^3A , R ^3B , R ^4A and R ^4B are preferably each independently a linear or branched alkyl group having 1 to 4 carbon atoms, and more preferably a methyl group or a t-butyl group.
R ^5A and R ^5B are preferably each independently a lower alkylene group having 1 to 4 carbon atoms, and more preferably an ethylene group. Incidentally, R ^5A, an alkylene group of R ^5B may further have an alkyl group as a substituent.
In the general formula (I), R ^1A = R ^1B , R ^2A = R ^2B , R ^3A = R ^3B , R ^4A = R ^4B , R ^5A = R ^5B and symmetrical with respect to the central carbon atom of the spiro ring It is preferable that it is a compound of these.

  As the phenol-based stabilizer (B-1) having such a spiro ring skeleton, specifically, 3,9-bis [2- {3- (3- tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy} 1,1-dimethylethyl] -2,4,8,10-tetraoxaspiro [5,5] undecane.

  Said (B-1) component may be used individually by 1 type, and may use 2 or more types together.

<A phosphite stabilizer having a spiro ring skeleton (B-2)>
The phosphite stabilizer (B-2) having a spiro ring skeleton is not particularly limited as long as it is a phosphite compound having a spiro ring skeleton. For example, it is represented by the following general formula (II). Those are preferred.

(In formula (II), R ^10A and R ^10B each independently represent an alkyl group having 1 to 30 carbon atoms or an aryl group having 6 to 30 carbon atoms.)

In the general formula (II), the alkyl groups represented by R ^10A and R ^10B are preferably each independently a linear or branched alkyl group having 1 to 10 carbon atoms. When R ^10A and R ^10B are aryl groups, aryl groups represented by any of the following general formulas (II-a), (II-b), or (II-c) are preferable.

(In formula (II-a), R ^A represents an alkyl group having 1 to 10 carbon atoms. In formula (II-b), R ^B represents an alkyl group having 1 to 10 carbon atoms.)

  The phosphite stabilizer (II-1) having a spiro ring skeleton represented by the general formula (II) may be a compound represented by the following general formula (II-1).

(In formula (II-1), R ^{11 to} R ¹⁸ each independently represents a hydrogen atom or an alkyl group, and R ^{19 to} R ²² each independently represents an alkyl group, an aryl group or an aralkyl group, a to d each independently represents an integer of 0 to 3.)

In the general formula (II-1), R ^{11 to} R ¹⁸ are each independently preferably an alkyl group having 1 to 5 carbon atoms, preferably a methyl group, and a to d are 0 is preferred.

  Examples of the phosphite stabilizer (B-2) having a spiro ring skeleton include bis (2,6-di-tert-butyl-4-methylphenyl) penta represented by the following structural formula (II-A). Erythritol diphosphite and bis (2,4-dicumylphenyl) pentaerythritol diphosphite represented by the following structural formula (II-B) are preferred.

  Said (B-2) component may be used individually by 1 type, or may use 2 or more types together.

<Content of stabilizer (B)>
In the aromatic polycarbonate resin composition of the present invention, the content of the component (B-1) is 0.005 to 0.1 parts by mass with respect to 100 parts by mass of the aromatic polycarbonate resin (A). When the content of the component (B-1) is less than 0.005 parts by mass, it is not possible to obtain a sufficient improvement effect of the residence heat stability. If the content of the component (B-1) exceeds 0.1 parts by mass, the amount of gas during molding increases or transfer defects due to mold deposits occur, so the light transmittance of the resulting molded product decreases. There is a fear. The content of the component (B-1) is preferably 0.008 to 0.08 parts by mass, more preferably 0.01 to 0.05 parts by mass with respect to 100 parts by mass of the aromatic polycarbonate resin (A). is there.

  In the aromatic polycarbonate resin composition of the present invention, the content of the component (B-2) is 0.005 to 0.1 parts by mass with respect to 100 parts by mass of the aromatic polycarbonate resin (A). When the content of the component (B-2) is less than 0.005 parts by mass, it is not possible to obtain a sufficient improvement effect of the residence heat stability. If the content of the component (B-2) exceeds 0.1 parts by mass, the amount of gas at the time of molding increases or transfer defects due to mold deposits occur, so the light transmittance of the resulting molded product decreases. There is a fear. The content of the component (B-2) is preferably 0.008 to 0.08 parts by mass, more preferably 0.01 to 0.05 parts by mass with respect to 100 parts by mass of the aromatic polycarbonate resin (A). is there.

  The component (B-1) and the component (B-2) are preferably used in a balanced manner in order to more reliably obtain the effect of improving the residence heat stability by using these in combination. The content weight ratio of the component (B-1) and the component (B-2) in the polycarbonate resin composition is in the range of (B-1) component: (B-2) component = 1: 0.5-2. Preferably, it is in the range of 1: 0.6 to 1.8, more preferably in the range of 1: 0.7 to 1.6. Moreover, the total content of the component (B-1) and the component (B-2) in the aromatic polycarbonate resin composition of the present invention is 0.01 to 100 parts by mass with respect to 100 parts by mass of the aromatic polycarbonate resin (A). The amount is preferably 0.15 parts by mass, more preferably 0.02 to 0.12 parts by mass, and still more preferably 0.03 to 0.1 parts by mass.

[Fatty acid ester (C)]
The aromatic polycarbonate resin composition of the present invention may contain a fatty acid ester (C) as a releasing agent in addition to the aromatic polycarbonate resin (A) and the stabilizer (B).
The fatty acid ester (C) is a condensation compound of an aliphatic carboxylic acid and an alcohol.

  Examples of the aliphatic carboxylic acid constituting the fatty acid ester (C) include saturated or unsaturated aliphatic monocarboxylic acid, dicarboxylic acid, and tricarboxylic acid. Here, the aliphatic carboxylic acid also includes an alicyclic carboxylic acid. As the aliphatic carboxylic acid, a monocarboxylic acid or dicarboxylic acid having 6 to 36 carbon atoms is preferable, and an aliphatic saturated monocarboxylic acid having 6 to 36 carbon atoms is more preferable. Specific examples of such aliphatic carboxylic acids include palmitic acid, stearic acid, valeric acid, caproic acid, capric acid, lauric acid, arachidic acid, behenic acid, lignoceric acid, serotic acid, melicic acid, tetratriacontanoic acid. , Montanic acid, glutaric acid, adipic acid and azelaic acid.

  On the other hand, examples of the alcohol include saturated or unsaturated monohydric alcohols and polyhydric alcohols. These alcohols may have a substituent such as a fluorine atom, a chlorine atom, a bromine atom or an aryl group. Among these alcohols, monovalent or polyvalent saturated alcohols having 30 or less carbon atoms are preferable, and aliphatic saturated monohydric alcohols or polyhydric alcohols having 30 or less carbon atoms are more preferable. Here, the aliphatic alcohol also includes an alicyclic alcohol.

  Examples of the alcohol include octanol, decanol, dodecanol, tetradecanol, stearyl alcohol, behenyl alcohol, ethylene glycol, diethylene glycol, glycerin, pentaerythritol, 2,2-dihydroxyperfluoropropanol, neopentylene glycol, ditrimethylolpropane, dipentaol. Examples include erythritol.

  Examples of the fatty acid ester (C) include beeswax (mixture containing myristyl palmitate as a main component), hydrogenated oil, butyl stearate, behenyl behenate, octyldodecyl behenate, stearyl stearate, glycerin monopalmitate, glycerin. Monostearate, glycerin monooleate, glycerin distearate, glycerin tristearate, pentaerythritol monopalmitate, pentaerythritol monostearate, pentaerythritol distearate, pentaerythritol tristearate, pentaerythritol tetrastearate, etc. It is done.

  The fatty acid ester (C) may be used alone or in combination of two or more.

  When the aromatic polycarbonate resin composition of the present invention contains the fatty acid ester (C), the content is 0.03 to 0.3 parts by mass with respect to 100 parts by mass of the aromatic polycarbonate resin (A). It is preferable. When content of fatty acid ester (C) is less than 0.03 mass part, there exists a tendency for the mold release property of the obtained molded article to become inadequate. On the other hand, when the content of the fatty acid ester (C) exceeds 0.3 parts by mass, the amount of gas at the time of molding increases or transfer defects due to mold deposits occur. May decrease. The content of the fatty acid ester (C) is more preferably 0.06 to 0.25 parts by mass, and still more preferably 0.08 to 0.2 parts by mass with respect to 100 parts by mass of the aromatic polycarbonate resin (A). It is.

[Ultraviolet absorber (D)]
The aromatic polycarbonate resin composition of the present invention may preferably contain an ultraviolet absorber (D). By containing the ultraviolet absorbent (D), the weather resistance of the aromatic polycarbonate resin composition of the present invention can be improved.

  Examples of the ultraviolet absorber (D) include inorganic ultraviolet absorbers such as cerium oxide and zinc oxide; benzotriazole compounds, benzophenone compounds, salicylate compounds, cyanoacrylate compounds, triazine compounds, oxanilide compounds, malonic ester compounds, hindered amine compounds, etc. Organic ultraviolet absorbers and the like can be mentioned. In these, an organic ultraviolet absorber is preferable and a benzotriazole compound is more preferable. By selecting the organic ultraviolet absorber, the transparency and mechanical properties of the aromatic polycarbonate resin composition of the present invention are improved.

  Examples of the benzotriazole compound include 2- (2′-hydroxy-5′-methylphenyl) benzotriazole, 2- [2′-hydroxy-3 ′, 5′-bis (α, α-dimethylbenzyl) phenyl]. -Benzotriazole, 2- (2'-hydroxy-3 ', 5'-di-tert-butyl-phenyl) -benzotriazole, 2- (2'-hydroxy-3'-tert-butyl-5'-methylphenyl) ) -5-chlorobenzotriazole, 2- (2′-hydroxy-3 ′, 5′-di-tert-butyl-phenyl) -5-chlorobenzotriazole), 2- (2′-hydroxy-3 ′, 5) '-Di-tert-amyl) -benzotriazole, 2- (2'-hydroxy-5'-tert-octylphenyl) benzotriazole, 2,2'- And tylene bis [4- (1,1,3,3-tetramethylbutyl) -6- (2N-benzotriazol-2-yl) phenol], among others, 2- (2′-hydroxy-5′-). tert-octylphenyl) benzotriazole, 2,2′-methylenebis [4- (1,1,3,3-tetramethylbutyl) -6- (2N-benzotriazol-2-yl) phenol] are preferred, especially 2 -(2'-Hydroxy-5'-tert-octylphenyl) benzotriazole is preferred. Specific examples of such benzotriazole compounds include “Seesorb 701”, “Seesorb 705”, “Seesorb 703”, “Seesorb 702”, “Seesorb 704”, “Seesorb 709” manufactured by Sipro Kasei Co., Ltd. “Biosorb 520”, “Biosorb 582”, “Biosorb 580”, “Biosorb 583”, Chemipro Kasei “Chemisorb 71”, “Chemisorb 72”, Cytec Industries “Siasorb UV5411”, Adeka “LA” -32 "," LA-38 "," LA-36 "," LA-34 "," LA-31 "," Tinubin P "," Tinubin 234 "," Tinubin 326 "," Ciba Specialty Chemicals " Tinuvin 327 "," Tinubin 328 ", etc. are mentioned.

  Examples of the benzophenone compound include 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid, 2-hydroxy-4-n-octoxybenzophenone, 2 -Hydroxy-n-dodecyloxybenzophenone, bis (5-benzoyl-4-hydroxy-2-methoxyphenyl) methane, 2,2'-dihydroxy-4-methoxybenzophenone, 2,2'-dihydroxy-4,4 ' Specific examples of such benzophenone compounds include “Seesorb 100”, “Seesorb 101”, “Seesorb 101S”, “Seesorb 102”, and “Seesorb 103” manufactured by Sipro Kasei Co., Ltd. “Biotechnology” "100", "Biosorb 110", "Biosorb 130", "Chemisorb 10", "Chemsorb 11", "Chemsorb 11S", "Chemsorb 12", "Chemsorb 13", "Chemsorb 111", BASF manufactured by Chemipro Kasei Co., Ltd. “Ubinul 400” manufactured by BASF, “Ubinur M-40” manufactured by BASF, “Ubinur MS-40” manufactured by BASF, “Siasorb UV9”, “Siasorb UV284”, “Siasorb UV531”, “Siasorb UV24” manufactured by Cytec Industries. And “Adeka Stub 1413”, “Adeka Stub LA-51” manufactured by Adeka Corporation.

  Examples of the salicylate compound include phenyl salicylate and 4-tert-butylphenyl salicylate. Specific examples of such a salicylate compound include “Seesorb 201”, “Seesorb 202”, and Chemipro manufactured by Cypro Kasei Co., Ltd. “Chemisorb 21”, “Chemisorb 22” manufactured by Kasei Co.

  Examples of the cyanoacrylate compound include ethyl-2-cyano-3,3-diphenyl acrylate, 2-ethylhexyl-2-cyano-3,3-diphenyl acrylate, and the like. For example, “Cisorb 501” manufactured by Sipro Kasei Co., Ltd. “Biosorb 910” manufactured by Kyodo Pharmaceutical Co., Ltd., “Ubisolator 300” manufactured by Daiichi Kasei Co., Ltd., “Ubinur N-35” manufactured by BASF, Can be mentioned.

  Examples of the oxanilide compound include 2-ethoxy-2′-ethyl oxalinic acid bis-arinide. Specific examples of such an oxalinide compound include “Sanduboa VSU” manufactured by Clariant Corporation. Can be mentioned.

  As the malonic acid ester compound, 2- (alkylidene) malonic acid esters are preferable, and 2- (1-arylalkylidene) malonic acid esters are more preferable. Specific examples of such a malonic ester compound include “PR-25” manufactured by Clariant Japan, “B-CAP” manufactured by Ciba Specialty Chemicals, and the like.

  The said ultraviolet absorber (D) may be used individually by 1 type, or may use 2 or more types together.

  When the aromatic polycarbonate resin composition of this invention contains a ultraviolet absorber (D), the content is 0.001-3 mass parts normally with respect to 100 mass parts of aromatic polycarbonate resin (A), Preferably Is 0.01 to 1 part by mass, more preferably 0.05 to 0.5 part by mass. When the content of the ultraviolet absorber (D) is less than the above lower limit, the effect of improving the weather resistance may be insufficient. When the content of the ultraviolet absorber exceeds the above upper limit, mold debossit, etc. May cause mold contamination.

[Other ingredients]
In the aromatic polycarbonate resin composition of the present invention, an antioxidant, a release agent, a fluorescent whitening agent, a dye / pigment, a flame retardant, an impact resistance improver, as optional components, as long as the object of the present invention is not impaired. An antistatic agent, a lubricant, a plasticizer, a compatibilizer, a filler and the like may be blended.

[Method for producing aromatic polycarbonate resin composition]
The method for producing the aromatic polycarbonate resin composition of the present invention is not particularly limited, and for example, at any stage until the final molded product is molded, the components are mixed together or divided and melt-kneaded. A method is mentioned. As a blending method of each component, for example, a method using a tumbler, a Henschel mixer or the like, a method of quantitatively feeding to an extruder hopper with a feeder and mixing, and the like can be mentioned. Examples of the melt kneading method include a method using a single screw kneading extruder, a twin screw kneading extruder, a kneader, a Banbury mixer, and the like.

[Molding method of aromatic polycarbonate resin composition]
Although there is no restriction | limiting in particular in the shaping | molding method of the aromatic polycarbonate resin composition of this invention, For example, an injection molding method, a compression molding method, an injection compression molding method etc. are mentioned, Preferably it is an injection molding method.

  In order to suppress thermal deterioration of the resin during molding and obtain an excellent initial hue, when molding the aromatic polycarbonate resin composition of the present invention, molding is performed in an inert gas atmosphere such as nitrogen. May be performed.

〔Molding〕
The molded article of the aromatic polycarbonate resin composition of the present invention is useful for a wide range of applications such as electrical equipment, communication equipment, precision machinery, automobile parts, etc., but the aromatic polycarbonate resin composition of the present invention is stable in residence heat stability. Excellent, even when the residence time in the molding machine is long during molding, there are few problems of molecular weight reduction and yellowing due to resin decomposition, and it is possible to obtain molded products with excellent mechanical properties such as impact resistance and hue Therefore, the molded product formed by molding the aromatic polycarbonate resin composition of the present invention is particularly suitable in the fields of mechanical properties such as impact resistance and transparency, and the lens cover, lighting cover, etc. where the hue is important. used. The molded article made of the aromatic polycarbonate resin composition of the present invention is particularly suitably used as an automotive lighting cover.

[ΔYI]
The aromatic polycarbonate resin composition of the present invention is excellent in residence heat stability, and yellowing during the heat residence process is suppressed. For example, the aromatic polycarbonate resin composition of the present invention has a YI value measured on a molded article having a thickness of 2 mm obtained by injection molding after holding the pellet of the aromatic polycarbonate resin composition of the present invention at 340 ° C. for 5 minutes. YI (5), and when the YI value measured for a molded article having a thickness of 2 mm obtained by injection molding after holding the pellet of the aromatic polycarbonate resin composition at 340 ° C. for 20 minutes is YI (20) The YI value increase amount ΔYI calculated by the following formula (1) is preferably excellent in heat-resistant yellowing such that it is preferably 0.3 or less. This ΔYI is more preferably 0.2 or less, and still more preferably 0.1 or less.
ΔYI = YI (20) −YI (5) (1)

  In addition, the YI value of a molded product is specifically measured by the method described in the section of Examples described later.

[ΔMv]
The aromatic polycarbonate resin composition of the present invention is excellent in residence heat stability and has a small decrease in molecular weight due to decomposition of the resin during the heat residence process. For example, the viscosity average molecular weight of the aromatic polycarbonate resin (A) contained in the aromatic polycarbonate resin composition pellets of the present invention is Mv (0), and the pellets are held at 340 ° C. for 20 minutes, and then molded by injection molding. When the viscosity average molecular weight of the aromatic polycarbonate resin (A) contained in the product is Mv (20), the heat resistance such that the decrease amount ΔMv of the viscosity average molecular weight calculated by the following formula (2) is preferably 1000 or less It is excellent in degradability. This ΔMv is more preferably 900 or less, and still more preferably 700 or less.
ΔMv = Mv (0) −Mv (20) (2)

  In addition, the viscosity average molecular weight of aromatic polycarbonate resin (A) is specifically measured by the method described in the item of the below-mentioned Example.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples unless it exceeds the gist.

  Hereinafter, the materials used in Examples and Comparative Examples are as follows.

[Aromatic polycarbonate resin (A)]
Aromatic polycarbonate resin manufactured by Mitsubishi Engineering Plastics: Bisphenol A type aromatic polycarbonate resin manufactured by interfacial polymerization (viscosity average molecular weight 21,500)

[Stabilizer (B)]
<Phenolic stabilizer (B-1)>
“ADEKA STAB AO-80” manufactured by ADEKA: 3,9-bis [2- {3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyl represented by the structural formula (I-1) Oxy} 1,1-dimethylethyl] -2,4,8,10-tetraoxaspiro [5,5] undecane. (In Tables 1 and 2, it is described as “AO-80”.)

<Other phenolic stabilizers>
"ADEKA STAB AO-60" manufactured by ADEKA: pentaerythritol tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl] propionate represented by the following structural formula (in Tables 1 and 2, "AO- 60 ”)

<Phosphite stabilizer (B-2)>
“ADEKA STAB PEP-36” manufactured by ADEKA: bis (2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite represented by the structural formula (II-A) (in Tables 1 and 2) , Described as “PEP-36”.)
“Doverphos S-9228” manufactured by Properties & Characteristics: bis (2,4-dicumylphenyl) pentaerythritol diphosphite represented by the structural formula (II-B) (in Tables 1 and 2, “S-9228” and (Describe)

<Other phosphite stabilizers>
“ADEKA STAB 2112” manufactured by ADEKA Corporation: Tris (2,4-di-tert-butylphenyl) phosphite represented by the following structural formula (indicated as “2112” in Tables 1 and 2)

<Fatty acid ester (C)>
“Roxyol VPG861” manufactured by Cognis Japan Co., Ltd .: Pentaerythritol tetrastearate (referred to as “VPG861” in Tables 1 and 2)

<Ultraviolet absorber (D)>
“Seesorb 709” manufactured by Cypro Kasei Co., Ltd .: 2- (2′-hydroxy-5′-tert-octylphenyl) -2H-benzotriazole (described as “Seesorb 709” in Tables 1 and 2)

[Examples 1-8 and Comparative Examples 1-9]
<Production of aromatic polycarbonate resin composition>
The components shown in Tables 1 and 2 were blended so as to have the ratios shown in Tables 1 and 2 and mixed uniformly with a tumbler mixer to obtain a mixture. This mixture is supplied to a single screw extruder (“VS-40” manufactured by Isuzu Chemical Industries Ltd.) equipped with a full flight screw and a vent, and the screw rotation speed is 80 rpm, the discharge rate is 20 kg / hour, and the barrel temperature is 250 ° C. Kneaded and extruded in a strand form from the tip of the extrusion nozzle. The extrudate was quenched in a water bath and cut and pelletized using a pelletizer to obtain pellets of an aromatic polycarbonate resin composition.

<Characteristic evaluation>
The aromatic polycarbonate resin composition obtained as described above was evaluated as follows, and the results are shown in Tables 1 and 2.

(1) YI value After drying pellets of an aromatic polycarbonate resin composition at 120 ° C. for 4 to 8 hours with a hot air circulation dryer, an injection molding machine (“ROBOSHOT-S-2000i 150B” manufactured by FANUC) is used. Then, a molded product having a thickness of 70 mm × 40 mm × 2 mm was molded at an injection temperature of 340 ° C., a residence time in the cylinder of 5 minutes, and a mold temperature of 80 ° C. About this molded article, the YI value of thickness 2mm was measured using Nippon Denshoku Industries Co., Ltd. product color meter "SE-2000". This YI value is assumed to be “YI (5)”.
Separately, injection molding was performed in the same manner as above except that the residence time in the cylinder was 20 minutes, and the YI value of 2 mm in thickness was measured in the same manner. This YI value is assumed to be “YI (20)”.
ΔYI was calculated from the following formula (1).
ΔYI = YI (20) −YI (5) (1)

(2) ΔMv
With respect to the pellets of the aromatic polycarbonate resin composition, the “viscosity average molecular weight” was measured by the following method. This value is assumed to be “Mv (0)”.
Separately, similarly to the measurement of YI (20), injection molding was performed with a residence time in the cylinder of 20 minutes to obtain a molded product, and the viscosity average molecular weight of this molded product was measured in the same manner. This value is assumed to be “MV (20)”.
ΔMv was calculated from the following equation (2).
ΔMv = Mv (0) −Mv (20) (2)

<Measurement method of viscosity average molecular weight>
Using methylene chloride as a solvent and using an Ubbelohde viscometer, the intrinsic viscosity ([η]) (unit dl / g) at a temperature of 20 ° C. was determined, and Schnell's viscosity formula: η = 1.23 × 10 ⁻⁴ Calculated from the equation of M ^0.83 . Here, the intrinsic viscosity ([η]) is a value calculated from the following equation by measuring the specific viscosity (η _sp ) at each solution concentration (C) (g / dl).

From Tables 1 and 2, it can be seen that the aromatic polycarbonate resin composition of the present invention has excellent residence heat stability and suppresses molecular weight reduction and yellowing during the thermal residence process.
In contrast, Comparative Examples 1 to 3 in which both the phenol stabilizer and the phosphite stabilizer do not satisfy the provisions of the present invention, or one of the phenol stabilizer and the phosphite stabilizer is the provision of the present invention. Comparative Examples 4 to 6, which do not satisfy the above, Comparative Example 7 using only one of a phenol-based stabilizer (B-1) having a spiro ring skeleton and a phosphite stabilizer (B-2) having a spiro ring skeleton In ˜9, the residence heat stability is inferior, and there are problems of molecular weight reduction and yellowing during the heat residence process.

Claims (8)

For 100 parts by mass of the aromatic polycarbonate resin (A) and the aromatic polycarbonate resin (A),
As stabilizer (B), 0.005-0.1 part by mass of a phenol-based stabilizer (B-1) having a spiro ring skeleton and 0.005 of a phosphite stabilizer (B-2) having a spiro ring skeleton Aromatic polycarbonate resin composition characterized by containing ~ 0.1 part by mass.   The aromatic polycarbonate resin according to claim 1, wherein the phenol-based stabilizer (B-1) having a spiro ring skeleton has a 2,4,8,10-tetraoxaspiro [5.5] undecane ring. Composition. 3. The aromatic polycarbonate resin composition according to claim 1, wherein the phosphite stabilizer (B-2) having a spiro ring skeleton is represented by the following general formula (II).

(In formula (II), R ^10A and R ^10B each independently represent an alkyl group having 1 to 30 carbon atoms or an aryl group having 6 to 30 carbon atoms.)   The content weight ratio of the phenol stabilizer (B-1) having a spiro ring skeleton and the phosphite stabilizer (B-2) having a spiro ring skeleton in any one of claims 1 to 3 is a spiro ring. Phenolic stabilizer having a skeleton (B-1): Phosphite stabilizer having a spiro ring skeleton (B-2) = 1: 0.5 to 2, and a phenol stabilizer having a spiro ring skeleton (B -1) and the total content of the phosphite stabilizer (B-2) having a spiro ring skeleton is 0.01 to 0.15 parts by mass with respect to 100 parts by mass of the aromatic polycarbonate resin (A). An aromatic polycarbonate resin composition characterized by that. 5. The YI value measured on a molded article having a thickness of 2 mm obtained by injection molding after holding the pellets of the aromatic polycarbonate resin composition at 340 ° C. for 5 minutes according to claim 1. 5) When the YI value measured for a molded article having a thickness of 2 mm obtained by injection molding after holding the pellet of the aromatic polycarbonate resin composition at 340 ° C. for 20 minutes is defined as YI (20), An aromatic polycarbonate resin composition, wherein the increase amount ΔYI of the YI value calculated in (1) is 0.3 or less.
ΔYI = YI (20) −YI (5) (1) The viscosity average molecular weight of the aromatic polycarbonate resin (A) contained in the aromatic polycarbonate resin composition pellet is Mv (0) and the aromatic polycarbonate resin composition pellet is 340 according to any one of claims 1 to 5. When the viscosity average molecular weight of the aromatic polycarbonate resin (A) contained in the molded product obtained by injection molding after holding at 20 ° C. for 20 minutes is Mv (20), the viscosity average calculated by the following formula (2) An aromatic polycarbonate resin composition having a molecular weight reduction amount ΔMv of 1000 or less.
ΔMv = Mv (0) −Mv (20) (2)   A molded article formed by molding the aromatic polycarbonate resin composition according to any one of claims 1 to 6.   The molded article according to claim 7, which is an automotive lighting cover.