JP6151615B2 - Polycarbonate resin composition and molded product - Google Patents

Description

  The present invention relates to a polycarbonate resin composition and a molded product, and more particularly to a polycarbonate resin composition excellent in fluidity, impact resistance, light reflectivity, light shielding properties, hue and heat resistance, and a molded product thereof.

  Polycarbonate resin is a resin excellent in heat resistance, mechanical properties, and electrical characteristics, and is widely used in, for example, automotive materials, electrical / electronic equipment materials, housing materials, and other parts manufacturing materials in industrial fields. . Among them, the light-reflective polycarbonate resin composition containing a white pigment such as titanium oxide is suitable for applications requiring light reflectivity and light shielding properties such as a light reflection plate and a light reflection frame of a liquid crystal display device and LED lighting. Used.

  On the other hand, polycarbonate resin cannot be said to have sufficient fluidity, and when it is used for a light reflecting plate and a light reflecting frame of a liquid crystal display device of a mobile phone, a smartphone, or a tablet that has been remarkably increased in size and thickness in recent years. A light-reflective polycarbonate resin excellent in fluidity is required.

  As a technique for improving the fluidity of the polycarbonate resin composition, there is a technique using a polycarbonate resin having a small molecular weight, but the polycarbonate resin composition has a feature that the impact resistance is lowered as the molecular weight is reduced. When this method was used, it was difficult to achieve both fluidity and impact resistance. In order to solve this problem, there is a method of adding a core / shell type elastomer. However, some elastomers are colored or have low thermal stability, and there is a concern that the molded product may be colored, so excessive addition may not be preferable.

As a technique for improving fluidity, there is a technique using a flow modifier having a molecular structure different from that of polycarbonate. As a typical flow modifier, a phosphate ester compound is known (Patent Document 1).
However, when phosphate ester is used, the impact resistance and heat resistance of the polycarbonate resin composition are lowered. In addition, the phosphoric acid ester has a drawback that it is not suitable for a liquid crystal display device that receives illumination light and is exposed to a high temperature because it has poor resistance to moist heat and easily causes heat discoloration.

Japanese Patent Laid-Open No. 10-1600

  The present invention was devised in view of the above-mentioned problems of the prior art, and provides a polycarbonate resin composition excellent in fluidity, impact resistance, light reflectivity, light shielding properties, hue and heat resistance, and a molded product thereof. For the purpose.

As a result of intensive studies in order to achieve the above-mentioned problems, the present inventor is surprised by containing two or more kinds of polycarbonate resins having a specific molecular weight, titanium oxide and elastomer in specific amounts. In particular, the present inventors have found that a polycarbonate composition that can achieve both high fluidity and impact resistance and that is excellent in light reflectivity, light shielding properties, hue and heat resistance, and bending resistance can be obtained, and the present invention is completed. It came to.
The present invention provides the following polycarbonate resin composition and molded article.

[1] The polycarbonate resin (A) contains 5 to 20 parts by mass of titanium oxide (B) and 1 to 10 parts by mass of the core / shell type elastomer (C) with respect to 100 parts by mass of the polycarbonate resin (A). A polycarbonate resin composition comprising 5 to 50% by mass of a polycarbonate resin (A1) having an average molecular weight of 4,000 to 10,000 and 50 to 95% by mass of a polycarbonate resin (A2) having a viscosity average molecular weight of 13,000 to 30,000.
[2] The polycarbonate resin composition according to the above [1], wherein a value of a deflection temperature under load measured in accordance with ISO 75-1 under a condition of 1.8 MPa is 105 ° C. or higher.
[3] A molded product formed by molding the polycarbonate resin composition according to [1] or [2].
[4] The molded article according to the above [3], wherein the thinnest portion has a thickness of 1 mm or less.
[5] The molded article according to the above [4], which is a liquid crystal display device reflection frame.
[6] The molded article according to the above [4], which is a liquid crystal display device reflecting plate.

The polycarbonate resin composition of the present invention has both high fluidity and impact resistance, is excellent in light reflectivity, light shielding properties, hue and heat resistance, and is excellent in thin-wall moldability and bending resistance.
Therefore, the polycarbonate resin composition of the present invention is suitable for a thin molded product having a thickness of 1 mm or less at the thinnest portion, and is particularly suitable for a reflection frame, a reflection plate, and the like of a liquid crystal display device. Moreover, since the bending characteristic is good, it is suitable for a molded product having a hinge structure.

  Hereinafter, although an embodiment, an example thing, etc. are shown and explained in detail about the present invention, the present invention is limited to an embodiment, an example, etc. shown below and is not interpreted.

[Overview]
The polycarbonate resin composition of the present invention contains 5 to 20 parts by mass of titanium oxide (B) and 1 to 10 parts by mass of a core / shell type elastomer (C) with respect to 100 parts by mass of the polycarbonate resin (A). (A) is characterized by comprising 5 to 50% by mass of a polycarbonate resin (A1) having a viscosity average molecular weight of 4000 to 10,000 and 50 to 95% by mass of a polycarbonate resin (A2) having a viscosity average molecular weight of 13,000 to 30000.

[Polycarbonate resin (A)]
The polycarbonate resin (A) used in the polycarbonate resin composition of the present invention is 5 to 50 mass% of the polycarbonate resin (A1) having a viscosity average molecular weight of 4000 to 10,000 and 50 to 95 mass% of the polycarbonate resin (A2) having a viscosity average molecular weight of 13,000 to 30000. %.

If the content of the polycarbonate resin (A1) having a viscosity average molecular weight as low as 4000 to 10,000 is less than 5% by mass, impact resistance is lowered. Moreover, when the content of the polycarbonate resin (A1) exceeds 50% by mass, classification is likely to occur when the polycarbonate resin composition raw material of the present invention is put into an extruder hopper, and the content of the polycarbonate resin (A1) during extrusion is included. The amount becomes difficult to stabilize, and mold deposits are easily generated during injection molding.
The polycarbonate resin (A2) used in combination with the polycarbonate resin (A1) is a polycarbonate resin (A2) having a viscosity average molecular weight of 13,000 to 30,000, and the content of the polycarbonate resin (A2) is less than 50% by mass. Classification is likely to occur when the polycarbonate resin composition raw material is put into an extruder hopper, the content of the polycarbonate resin (A1) is difficult to stabilize during extrusion, and mold deposits are easily generated during injection molding. If it exceeds mass%, the impact resistance will decrease.

  The preferable content of the polycarbonate resin (A1) and the polycarbonate resin (A2) is 6 to 45% by mass of the polycarbonate resin (A1), 55 to 94% by mass of the polycarbonate resin (A2), more preferably 7 to 40% of the polycarbonate resin (A1). % By mass, 60 to 93% by mass of the polycarbonate resin (A2), more preferably 8 to 35% by mass of the polycarbonate resin (A1), and 65 to 92% by mass of the polycarbonate resin (A2).

The viscosity average molecular weight [Mv] is determined by using the methylene chloride as a solvent and obtaining the intrinsic viscosity [η] (unit dl / g) at a temperature of 20 ° C. using an Ubbelohde viscometer, and the Schnell viscosity formula, It means a value calculated from η = 1.23 × 10 ⁻⁴ Mv ^0.83 . 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).

  There is no restriction | limiting in the kind of polycarbonate resin (A1) and polycarbonate resin (A2). Moreover, polycarbonate resin (A1) and (A2) may use one type, and may use two or more types together by arbitrary combinations and arbitrary ratios.

  The polycarbonate resin is a polymer having a basic structure having a carbonic acid bond, represented by a general formula: — [— O—X—O—C (═O) —] —. In the formula, X is generally a hydrocarbon group, but for imparting various properties, X introduced with a hetero atom or a hetero bond may be used.

  The polycarbonate resin can be classified into an aromatic polycarbonate resin in which carbon directly bonded to a carbonic acid bond is aromatic carbon and an aliphatic polycarbonate resin in which aliphatic carbon is aliphatic carbon, either of which can be used. Of these, aromatic polycarbonate resins are preferred from the viewpoints of heat resistance, mechanical properties, electrical characteristics, and the like.

  Although there is no restriction | limiting in the specific kind of polycarbonate resin (A1) and (A2), For example, the polycarbonate polymer formed by making a dihydroxy compound and a carbonate precursor react is mentioned. At this time, in addition to the dihydroxy compound and the carbonate precursor, a polyhydroxy compound or the like may be reacted. Further, a method of reacting carbon dioxide with a cyclic ether using a carbonate precursor may be used. The polycarbonate polymer may be linear or branched. Further, the polycarbonate polymer may be a homopolymer composed of one type of repeating unit or a copolymer having two or more types of repeating units. At this time, the copolymer can be selected from various copolymerization forms such as a random copolymer and a block copolymer. In general, such a polycarbonate polymer is a thermoplastic resin.

Among monomers used as raw materials for aromatic polycarbonate resins, examples of aromatic dihydroxy compounds include:
Dihydroxybenzenes such as 1,2-dihydroxybenzene, 1,3-dihydroxybenzene (ie, resorcinol), 1,4-dihydroxybenzene;
Dihydroxybiphenyls such as 2,5-dihydroxybiphenyl, 2,2′-dihydroxybiphenyl, 4,4′-dihydroxybiphenyl;
2,2′-dihydroxy-1,1′-binaphthyl, 1,2-dihydroxynaphthalene, 1,3-dihydroxynaphthalene, 2,3-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, , 7-dihydroxynaphthalene, dihydroxynaphthalene such as 2,7-dihydroxynaphthalene;

2,2′-dihydroxydiphenyl ether, 3,3′-dihydroxydiphenyl ether, 4,4′-dihydroxydiphenyl ether, 4,4′-dihydroxy-3,3′-dimethyldiphenyl ether, 1,4-bis (3-hydroxyphenoxy) Dihydroxy diaryl ethers such as benzene and 1,3-bis (4-hydroxyphenoxy) benzene;

2,2-bis (4-hydroxyphenyl) propane (ie, bisphenol A),
1,1-bis (4-hydroxyphenyl) propane,
2,2-bis (3-methyl-4-hydroxyphenyl) propane,
2,2-bis (3-methoxy-4-hydroxyphenyl) propane,
2- (4-hydroxyphenyl) -2- (3-methoxy-4-hydroxyphenyl) propane,
1,1-bis (3-tert-butyl-4-hydroxyphenyl) propane,
2,2-bis (3,5-dimethyl-4-hydroxyphenyl) propane,
2,2-bis (3-cyclohexyl-4-hydroxyphenyl) propane,
2- (4-hydroxyphenyl) -2- (3-cyclohexyl-4-hydroxyphenyl) propane,
α, α′-bis (4-hydroxyphenyl) -1,4-diisopropylbenzene,
1,3-bis [2- (4-hydroxyphenyl) -2-propyl] benzene,
Bis (4-hydroxyphenyl) methane,
Bis (4-hydroxyphenyl) cyclohexylmethane,
Bis (4-hydroxyphenyl) phenylmethane,
Bis (4-hydroxyphenyl) (4-propenylphenyl) methane,
Bis (4-hydroxyphenyl) diphenylmethane,
Bis (4-hydroxyphenyl) naphthylmethane,
1,1-bis (4-hydroxyphenyl) ethane,
1,1-bis (4-hydroxyphenyl) -1-phenylethane,
1,1-bis (4-hydroxyphenyl) -1-naphthylethane,
1,1-bis (4-hydroxyphenyl) butane,
2,2-bis (4-hydroxyphenyl) butane,
2,2-bis (4-hydroxyphenyl) pentane,
1,1-bis (4-hydroxyphenyl) hexane,
2,2-bis (4-hydroxyphenyl) hexane,
1,1-bis (4-hydroxyphenyl) octane,
2,2-bis (4-hydroxyphenyl) octane,
1,1-bis (4-hydroxyphenyl) hexane,
2,2-bis (4-hydroxyphenyl) hexane,
4,4-bis (4-hydroxyphenyl) heptane,
2,2-bis (4-hydroxyphenyl) nonane,
1,1-bis (4-hydroxyphenyl) decane,
1,1-bis (4-hydroxyphenyl) dodecane,
Bis (hydroxyaryl) alkanes such as;

1,1-bis (4-hydroxyphenyl) cyclopentane,
1,1-bis (4-hydroxyphenyl) cyclohexane,
1,1-bis (4-hydroxyphenyl) -3,3-dimethylcyclohexane,
1,1-bis (4-hydroxyphenyl) -3,4-dimethylcyclohexane,
1,1-bis (4-hydroxyphenyl) -3,5-dimethylcyclohexane,
1,1-bis (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane,
1,1-bis (4-hydroxy-3,5-dimethylphenyl) -3,3,5-trimethylcyclohexane,
1,1-bis (4-hydroxyphenyl) -3-propyl-5-methylcyclohexane,
1,1-bis (4-hydroxyphenyl) -3-tert-butyl-cyclohexane,
1,1-bis (4-hydroxyphenyl) -3-tert-butyl-cyclohexane,
1,1-bis (4-hydroxyphenyl) -3-phenylcyclohexane,
1,1-bis (4-hydroxyphenyl) -4-phenylcyclohexane,
Bis (hydroxyaryl) cycloalkanes such as;

9,9-bis (4-hydroxyphenyl) fluorene,
Cardio structure-containing bisphenols such as 9,9-bis (4-hydroxy-3-methylphenyl) fluorene;

4,4′-dihydroxydiphenyl sulfide,
Dihydroxydiaryl sulfides such as 4,4′-dihydroxy-3,3′-dimethyldiphenyl sulfide;

4,4′-dihydroxydiphenyl sulfoxide,
Dihydroxydiaryl sulfoxides such as 4,4′-dihydroxy-3,3′-dimethyldiphenyl sulfoxide;

4,4′-dihydroxydiphenyl sulfone,
Dihydroxydiaryl sulfones such as 4,4′-dihydroxy-3,3′-dimethyldiphenyl sulfone;
Etc.

Among these, bis (hydroxyaryl) alkanes are preferable, and bis (4-hydroxyphenyl) alkanes are preferable, and 2,2-bis (4-hydroxyphenyl) propane (ie, from the viewpoint of impact resistance and heat resistance). Bisphenol A) is preferred.
In addition, 1 type may be used for an aromatic dihydroxy compound and it may use 2 or more types together by arbitrary combinations and a ratio.

In addition, when an example of a monomer that is a raw material of the aliphatic polycarbonate resin is given,
Ethane-1,2-diol, propane-1,2-diol, propane-1,3-diol, 2,2-dimethylpropane-1,3-diol, 2-methyl-2-propylpropane-1,3- Alkanediols such as diol, butane-1,4-diol, pentane-1,5-diol, hexane-1,6-diol, decane-1,10-diol;

  Cyclopentane-1,2-diol, cyclohexane-1,2-diol, cyclohexane-1,4-diol, 1,4-cyclohexanedimethanol, 4- (2-hydroxyethyl) cyclohexanol, 2,2,4, Cycloalkanediols such as 4-tetramethyl-cyclobutane-1,3-diol;

  Glycols such as ethylene glycol, 2,2'-oxydiethanol (ie, diethylene glycol), triethylene glycol, propylene glycol, spiro glycol and the like;

  1,2-benzenedimethanol, 1,3-benzenedimethanol, 1,4-benzenedimethanol, 1,4-benzenediethanol, 1,3-bis (2-hydroxyethoxy) benzene, 1,4-bis ( 2-hydroxyethoxy) benzene, 2,3-bis (hydroxymethyl) naphthalene, 1,6-bis (hydroxyethoxy) naphthalene, 4,4′-biphenyldimethanol, 4,4′-biphenyldiethanol, 1,4- Aralkyl diols such as bis (2-hydroxyethoxy) biphenyl, bisphenol A bis (2-hydroxyethyl) ether, bisphenol S bis (2-hydroxyethyl) ether;

  1,2-epoxyethane (ie ethylene oxide), 1,2-epoxypropane (ie propylene oxide), 1,2-epoxycyclopentane, 1,2-epoxycyclohexane, 1,4-epoxycyclohexane, 1-methyl And cyclic ethers such as -1,2-epoxycyclohexane, 2,3-epoxynorbornane, and 1,3-epoxypropane;

  Among the monomers used as the raw material for the aromatic polycarbonate resin, carbonyl halides, carbonate esters and the like are used as examples of the carbonate precursor. In addition, 1 type may be used for a carbonate precursor and it may use 2 or more types together by arbitrary combinations and a ratio.

  Specific examples of carbonyl halides include phosgene; haloformates such as bischloroformate of dihydroxy compounds and monochloroformate of dihydroxy compounds.

  Specific examples of the carbonate ester include diaryl carbonates such as diphenyl carbonate and ditolyl carbonate; dialkyl carbonates such as dimethyl carbonate and diethyl carbonate; biscarbonate bodies of dihydroxy compounds, monocarbonate bodies of dihydroxy compounds, and cyclic carbonates. And carbonate bodies of dihydroxy compounds such as

-Manufacturing method of polycarbonate resin The manufacturing method of polycarbonate resin is not specifically limited, Arbitrary methods are employable. Examples thereof include an interfacial polymerization method, a melt transesterification method, a pyridine method, a ring-opening polymerization method of a cyclic carbonate compound, and a solid phase transesterification method of a prepolymer. Hereinafter, a particularly preferable one of these methods will be specifically described.

.. Interfacial polymerization method First, the case where a polycarbonate resin is produced by the interfacial polymerization method will be described. In the interfacial polymerization method, a dihydroxy compound and a carbonate precursor (preferably phosgene) are reacted in the presence of an organic solvent inert to the reaction and an aqueous alkaline solution, usually at a pH of 9 or higher. Polycarbonate resin is obtained by interfacial polymerization in the presence. In the reaction system, a molecular weight adjusting agent (terminal terminator) may be present as necessary, or an antioxidant may be present to prevent the oxidation of the dihydroxy compound.

  The dihydroxy compound and the carbonate precursor are as described above. Of the carbonate precursors, phosgene is preferably used, and a method using phosgene is particularly called a phosgene method.

  Examples of the organic solvent inert to the reaction include chlorinated hydrocarbons such as dichloromethane, 1,2-dichloroethane, chloroform, monochlorobenzene and dichlorobenzene; aromatic hydrocarbons such as benzene, toluene and xylene; It is done. In addition, 1 type may be used for an organic solvent and it may use 2 or more types together by arbitrary combinations and a ratio.

  Examples of the alkali compound contained in the alkaline aqueous solution include alkali metal compounds and alkaline earth metal compounds such as sodium hydroxide, potassium hydroxide, lithium hydroxide, and sodium hydrogen carbonate, among which sodium hydroxide and water Potassium oxide is preferred. In addition, 1 type may be used for an alkali compound and it may use 2 or more types together by arbitrary combinations and a ratio.

  Although there is no restriction | limiting in the density | concentration of the alkali compound in alkaline aqueous solution, Usually, in order to control pH in the alkaline aqueous solution of reaction to 10-12, it is used at 5-10 mass%. For example, when phosgene is blown, the molar ratio of the bisphenol compound and the alkali compound is usually 1: 1.9 or more in order to control the pH of the aqueous phase to be 10 to 12, preferably 10 to 11. Among these, it is preferable that the ratio is 1: 2.0 or more, usually 1: 3.2 or less, and more preferably 1: 2.5 or less.

  Examples of the polymerization catalyst include aliphatic tertiary amines such as trimethylamine, triethylamine, tributylamine, tripropylamine, and trihexylamine; alicyclic rings such as N, N′-dimethylcyclohexylamine and N, N′-diethylcyclohexylamine. Formula tertiary amines; aromatic tertiary amines such as N, N′-dimethylaniline and N, N′-diethylaniline; quaternary ammonium salts such as trimethylbenzylammonium chloride, tetramethylammonium chloride, triethylbenzylammonium chloride, etc. Pyridine; guanine; guanidine salt; and the like. In addition, 1 type may be used for a polymerization catalyst and it may use 2 or more types together by arbitrary combinations and a ratio.

  Examples of the molecular weight regulator include aromatic phenols having a monohydric phenolic hydroxyl group; aliphatic alcohols such as methanol and butanol; mercaptans; phthalimides and the like. Of these, aromatic phenols are preferred. Specific examples of such aromatic phenols include alkyl groups such as m-methylphenol, p-methylphenol, m-propylphenol, p-propylphenol, p-tert-butylphenol, and p-long chain alkyl-substituted phenol. Examples thereof include substituted phenols; vinyl group-containing phenols such as isopropanyl phenol; epoxy group-containing phenols; carboxyl group-containing phenols such as o-hydroxybenzoic acid and 2-methyl-6-hydroxyphenylacetic acid; In addition, a molecular weight regulator may use 1 type and may use 2 or more types together by arbitrary combinations and a ratio.

  The usage-amount of a molecular weight regulator is 0.5 mol or more normally with respect to 100 mol of dihydroxy compounds, Preferably it is 1 mol or more, and is 50 mol or less normally, Preferably it is 30 mol or less. By making the usage-amount of a molecular weight modifier into this range, the thermal stability and hydrolysis resistance of a polycarbonate resin composition can be improved.

In the reaction, the order of mixing the reaction substrate, reaction medium, catalyst, additive and the like is arbitrary as long as a desired polycarbonate resin is obtained, and an appropriate order may be arbitrarily set. For example, when phosgene is used as the carbonate precursor, the molecular weight regulator can be mixed at any time as long as it is between the reaction (phosgenation) of the dihydroxy compound and phosgene and the start of the polymerization reaction.
In addition, reaction temperature is 0-40 degreeC normally, and reaction time is normally several minutes (for example, 10 minutes)-several hours (for example, 6 hours).

-Melt transesterification method Next, the case where a polycarbonate resin is manufactured by the melt transesterification method is demonstrated. In the melt transesterification method, for example, a transesterification reaction between a carbonic acid diester and a dihydroxy compound is performed.

The dihydroxy compound is as described above.
On the other hand, examples of the carbonic acid diester include dialkyl carbonate compounds such as dimethyl carbonate, diethyl carbonate, and di-tert-butyl carbonate; diphenyl carbonate; substituted diphenyl carbonate such as ditolyl carbonate, and the like. Among these, diphenyl carbonate and substituted diphenyl carbonate are preferable, and diphenyl carbonate is more preferable. In addition, carbonic acid diester may use 1 type and may use 2 or more types together by arbitrary combinations and a ratio.

  The ratio of the dihydroxy compound and the carbonic acid diester is arbitrary as long as the desired polycarbonate resin can be obtained, but it is preferable to use an equimolar amount or more of the carbonic acid diester with respect to 1 mol of the dihydroxy compound. Is more preferable. The upper limit is usually 1.30 mol or less. By setting it as such a range, the amount of terminal hydroxyl groups can be adjusted to a suitable range.

  In the polycarbonate resin, the amount of terminal hydroxyl groups tends to have a great influence on thermal stability, hydrolysis stability, color tone and the like. For this reason, you may adjust the amount of terminal hydroxyl groups as needed by a well-known arbitrary method. In the transesterification reaction, a polycarbonate resin in which the amount of terminal hydroxyl groups is adjusted can be usually obtained by adjusting the mixing ratio of the carbonic diester and the aromatic dihydroxy compound; the degree of vacuum during the transesterification reaction, and the like. In addition, the molecular weight of the polycarbonate resin usually obtained can also be adjusted by this operation.

When adjusting the amount of terminal hydroxyl groups by adjusting the mixing ratio of the carbonic acid diester and the dihydroxy compound, the mixing ratio is as described above.
Further, as a more aggressive adjustment method, there may be mentioned a method in which a terminal terminator is mixed separately during the reaction. Examples of the terminal terminator at this time include monohydric phenols, monovalent carboxylic acids, carbonic acid diesters, and the like. In addition, 1 type may be used for a terminal terminator and it may use 2 or more types together by arbitrary combinations and a ratio.

  When producing a polycarbonate resin by the melt transesterification method, a transesterification catalyst is usually used. Any transesterification catalyst can be used. Among them, it is preferable to use, for example, an alkali metal compound and / or an alkaline earth metal compound. In addition, auxiliary compounds such as basic boron compounds, basic phosphorus compounds, basic ammonium compounds, and amine compounds may be used in combination. In addition, 1 type may be used for a transesterification catalyst and it may use 2 or more types together by arbitrary combinations and a ratio.

  In the melt transesterification method, the reaction temperature is usually 100 to 320 ° C. The pressure during the reaction is usually a reduced pressure condition of 2 mmHg or less. As a specific operation, a melt polycondensation reaction may be performed under the above-mentioned conditions while removing a by-product such as an aromatic hydroxy compound.

  The melt polycondensation reaction can be performed by either a batch method or a continuous method. When performing by a batch type, the order which mixes a reaction substrate, a reaction medium, a catalyst, an additive, etc. is arbitrary as long as a desired aromatic polycarbonate resin is obtained, What is necessary is just to set an appropriate order arbitrarily. However, considering the stability of the polycarbonate resin and the polycarbonate resin composition, the melt polycondensation reaction is preferably carried out continuously.

  In the melt transesterification method, a catalyst deactivator may be used as necessary. As the catalyst deactivator, a compound that neutralizes the transesterification catalyst can be arbitrarily used. Examples thereof include sulfur-containing acidic compounds and derivatives thereof. In addition, 1 type may be used for a catalyst deactivator and it may use 2 or more types together by arbitrary combinations and a ratio.

  The amount of the catalyst deactivator used is usually 0.5 equivalents or more, preferably 1 equivalent or more, and usually 10 equivalents or less, relative to the alkali metal or alkaline earth metal contained in the transesterification catalyst. Preferably it is 5 equivalents or less. Furthermore, it is 1 ppm or more normally with respect to aromatic polycarbonate resin, and is 100 ppm or less normally, Preferably it is 20 ppm or less.

  The polycarbonate resin composition of the present invention can also contain other polycarbonate resins not corresponding to the above polycarbonate resins (A1) and (A2), and when included, the content of the other polycarbonate resins is the polycarbonate resin. It is preferably 15 parts by mass or less, more preferably 12 parts by mass or less, still more preferably 10 parts by mass or less, and particularly preferably 7 parts by mass with respect to 100 parts by mass in total of (A1) and (A2). Or less.

[Titanium oxide (B)]
The polycarbonate resin composition of the present invention contains 5 to 20 parts by mass of titanium oxide (B) with respect to 100 parts by mass of the polycarbonate resin (A).
As for the titanium oxide used for titanium oxide (B), a manufacturing method, a crystal form, an average particle diameter, etc. are not specifically limited. There are sulfuric acid method and chlorine method in the production method of titanium oxide, but titanium oxide produced by sulfuric acid method tends to be inferior in whiteness of the composition to which this is added, so the object of the present invention can be effectively achieved. To achieve this, those produced by the chlorine method are preferred.

  Further, the crystal form of titanium oxide includes a rutile type and an anatase type, but a rutile type crystal form is preferable from the viewpoint of light resistance. It is preferable that the average particle diameter of a titanium oxide (B) is 0.1-0.7 micrometer, More preferably, it is 0.1-0.4 micrometer. When the average particle size is less than 0.1 μm, the light shielding property of the molded product is inferior, and when it exceeds 0.7 μm, the surface of the molded product is easily roughened, and the mechanical strength of the molded product tends to be lowered. Two or more types of titanium oxide having different average particle diameters may be mixed and used.

  The titanium oxide (B) is preferably surface-treated with an organosiloxane-based surface treatment agent, but before that, it is preferably pretreated with an alumina-based surface treatment agent. Alumina hydrate is preferably used as the alumina-based surface treatment agent. Furthermore, it may be pretreated with silicic acid hydrate together with alumina hydrate. The pretreatment method is not particularly limited, and any method can be used. The pretreatment with alumina hydrate and, if necessary, silicic acid hydrate is preferably carried out in the range of 1 to 15% by weight with respect to titanium oxide.

  Titanium oxide with alumina hydrate, pretreated with silicic acid hydrate if necessary, further improves the thermal stability by surface-treating the surface with an organosiloxane surface treatment agent. In addition, the uniform dispersibility in the polycarbonate resin composition and the stability of the dispersed state are improved, which is preferable.

  As the organosiloxane surface treating agent, a reactive functional group-containing organosilicon compound having a reactive functional group that reacts with the surface of the inorganic compound particles is preferable. Examples of reactive functional groups include Si-H groups, Si-OH groups, Si-NH groups, and Si-OR groups, but those having Si-H groups, Si-OH groups, and Si-OR groups. More preferred are Si-H group-containing organosilicon compounds having Si-H groups.

  The Si—H group-containing organosilicon compound is not particularly limited as long as it is a compound having a Si—H group in the molecule, and may be appropriately selected and used. Among them, poly (methyl hydrogensiloxane), polycyclo (Methylhydrogensiloxane), poly (ethylhydrogensiloxane), poly (phenylhydrogensiloxane), poly [(methylhydrogensiloxane) (dimethylsiloxane)] copolymer, poly [(methylhydrogensiloxane) (ethylmethylsiloxane) )] Copolymer, poly [(methylhydrogensiloxane) (diethylsiloxane)] copolymer, poly [(methylhydrogensiloxane) (hexylmethylsiloxane)] copolymer, poly [(methylhydrogensiloxane) (octylmethy) Siloxane)] copolymer, poly [(methylhydrogensiloxane) (phenylmethylsiloxane)] copolymer, poly [(methylhydrogensiloxane) (diethoxysiloxane)] copolymer, poly [(methylhydrogensiloxane) (dimethoxysiloxane)] Copolymer, poly [(methylhydrogensiloxane) (3,3,3-trifluoropropylmethylsiloxane)] copolymer, poly [(dihydrogensiloxane) ((2-methoxyethoxy) methylsiloxane)] copolymer, poly [( Polyorganohydrogensiloxanes such as dihydrogensiloxane) (phenoxymethylsiloxane)] copolymers are preferred.

  Surface treatment methods using an organosiloxane surface treatment agent for titanium oxide include (1) a wet method and (2) a dry method. In the wet method, a mixture of an organosiloxane-based surface treatment agent and a solvent is added with alumina hydrate, and if necessary, titanium oxide pretreated with silicic acid hydrate. Further, the heat treatment is performed at 100 to 300 ° C. thereafter. In the dry method, pretreated titanium oxide and polyorganohydrogensiloxane are mixed with a Henschel mixer in the same manner as described above, and an organic solution of polyorganohydrogensiloxane is sprayed on the pretreated titanium oxide. And a method of heat-treating at 100 to 300 ° C.

The treatment amount of the siloxane compound is usually 0.01 to 10 parts by mass with respect to 100 parts by mass of titanium oxide (B). When the amount of treatment is less than the above lower limit, the surface treatment effect is low, the polycarbonate resin composition of the present invention is yellowed, and the reflectance tends to be lowered. Moreover, when the amount of treatment exceeds the above upper limit, the amount of gas generated in the polycarbonate resin composition of the present invention is increased, which may cause mold contamination and poor appearance of the molding surface, which is not preferable.
From such a viewpoint, the processing amount is more preferably 0.1 to 6 parts by mass, further preferably 0.5 to 5 parts by mass, and particularly preferably 1 to 4 parts by mass with respect to 100 parts by mass of titanium oxide (B). preferable.

  The preferable content of titanium oxide (B) is 6 parts by mass or more, more preferably 7 parts by mass or more, still more preferably 8 parts by mass or more, preferably 100 parts by mass of the polycarbonate resin (A). 19 parts by mass or less, more preferably 18 parts by mass or less, and still more preferably 17 parts by mass or less.

[Core / shell type elastomer (C)]
The polycarbonate resin composition of the present invention contains a core / shell type elastomer (C).
As the core / shell type elastomer (C), a rubber component is used as a core layer, and a (meth) acrylic acid ester compound, a (meth) acrylic acid compound, an aromatic vinyl compound, and an unsaturated nitrile compound are selected around the rubber layer. A core / shell type graft copolymer comprising a shell layer formed by copolymerizing at least one monomer component is preferred.

  Specific examples of the rubber component include polybutadiene rubber, polyisoprene rubber, polybutyl acrylate and poly (2-ethylhexyl acrylate), polyalkyl acrylate rubber such as butyl acrylate-2-ethylhexyl acrylate copolymer, and polyorganosiloxane rubber. Silicone rubber, butadiene-acrylic composite rubber, composite rubber made of polyorganosiloxane rubber and polyalkylacrylate rubber, styrene-butadiene rubber, ethylene-propylene rubber, ethylene-butene rubber, ethylene-α-olefin system such as ethylene-octene rubber Examples thereof include rubber, ethylene-acrylic rubber, and fluorine rubber. These may be used alone or in admixture of two or more.

  In the present invention, the core / shell type elastomer (C) is preferably a core / shell having an acrylic rubbery polymer as a core layer and an acrylic polymer or copolymer component as a shell layer around it. Type elastomer.

  The acrylic rubbery polymer constituting the core layer is composed of an acrylic component. The core of the acrylic component can be obtained by polymerizing an unsaturated nitrile compound such as a (meth) acrylic acid ester compound or acrylonitrile.

  As the acrylic rubbery polymer constituting the core layer, the glass transition temperature is usually 0 ° C. or lower, preferably −20 ° C. or lower, more preferably −30 ° C. or lower. Specific examples of the rubber component include polybutyl acrylate, poly (2-ethylhexyl acrylate), and butyl acrylate / 2-ethylhexyl acrylate copolymer. These may be used alone or in admixture of two or more.

  Aromatic polyfunctional vinyl compounds such as divinylbenzene and divinyltoluene; polyvalent compounds such as ethylene glycol dimethacrylate, 1,3-butanediol diacrylate, trimethylolethane triacrylate, trimethylolpropane trimethacrylate, pentaerythritol tetramethacrylate Unsaturated carboxylic acid esters of alcohol; unsaturated carboxylic acid allyl esters such as allyl acrylate and allyl methacrylate; cross-linking monomers such as di- and triallyl compounds such as diallyl phthalate, diallyl sebacate, and triallyl triazine You can also

The shell of the acrylic component can be obtained by polymerizing a (meth) acrylic acid ester compound, a (meth) acrylic acid compound, or the like.
Examples of (meth) acrylic acid ester compounds include (meth) acrylic acid alkyl esters such as methyl methacrylate, ethyl methacrylate, n-butyl methacrylate and hexyl methacrylate; aryl (meth) acrylates such as phenyl methacrylate and naphthyl methacrylate; glycidyl acrylate and glycidyl Examples thereof include glycidyl group-containing (meth) acrylates such as methacrylate; among them, methacrylic acid alkyl esters are preferable, and methyl methacrylate is more preferable.
In addition, the said (meth) acrylic acid ester compound can use 1 type (s) or 2 or more types.

  In addition to the (meth) acrylic acid ester compound, other vinyl monomers may be contained. Other vinyl monomers include, for example, aromatic vinyls such as styrene and α-methylstyrene; unsaturated nitriles such as acrylonitrile and methacrylonitrile; vinyl ethers such as methyl vinyl ether and butyl vinyl ether; maleimide, N -Maleimide compounds such as methylmaleimide and N-phenylmaleimide; α, β-unsaturated carboxylic acid compounds such as maleic acid, phthalic acid and itaconic acid, and anhydrides thereof (for example, maleic anhydride); and the like.

  Furthermore, aromatic polyfunctional vinyl compounds such as divinylbenzene and divinyltoluene; polyvalent compounds such as ethylene glycol dimethacrylate, 1,3-butanediol diacrylate, trimethylolethane triacrylate, trimethylolpropane trimethacrylate, pentaerythritol tetramethacrylate Unsaturated carboxylic acid esters of alcohol; unsaturated carboxylic acid allyl esters such as allyl acrylate and allyl methacrylate; cross-linking monomers such as di- and triallyl compounds such as diallyl phthalate, diallyl sebacate, and triallyl triazine You can also

In the present invention, such a core / shell type elastomer (C) is used in combination with the polycarbonate resins (A1) and (A2) and titanium oxide (B), thereby achieving both high fluidity and impact resistance. It is possible to obtain a polycarbonate resin composition having excellent light reflectivity, light shielding properties, hue and heat resistance, as well as excellent thin moldability and bending resistance.
Content of a core / shell type elastomer (C) is 1-10 mass parts with respect to 100 mass parts of polycarbonate resin (A). When the content of the core / shell type elastomer (C) is less than 1 part by mass, the impact resistance improvement effect is insufficient, and when the content exceeds 10 parts by mass, the thermal stability deteriorates. The whiteness of the molded product tends to decrease. The content of the core / shell type elastomer (B) is preferably 1.5 parts by mass or more, more preferably 2 parts by mass or more, and preferably 9 parts by mass or less, more preferably 8 parts by mass or less. .

[Phosphorus stabilizer]
The polycarbonate resin composition of the present invention preferably contains a phosphorus stabilizer. Any known phosphorous stabilizer can be used. Specific examples include phosphorus oxo acids such as phosphoric acid, phosphonic acid, phosphorous acid, phosphinic acid, and polyphosphoric acid; acidic pyrophosphate metal salts such as acidic sodium pyrophosphate, acidic potassium pyrophosphate, and acidic calcium pyrophosphate; phosphoric acid Group 1 or Group 2B metal phosphates such as potassium, sodium phosphate, cesium phosphate and zinc phosphate; organic phosphate compounds, organic phosphite compounds, organic phosphonite compounds, etc. Particularly preferred.

Organic phosphite compounds include triphenyl phosphite, tris (monononylphenyl) phosphite, tris (monononyl / dinonyl phenyl) phosphite, tris (2,4-di-tert-butylphenyl) phosphite, monooctyl Diphenyl phosphite, dioctyl monophenyl phosphite, monodecyl diphenyl phosphite, didecyl monophenyl phosphite, tridecyl phosphite, trilauryl phosphite, tristearyl phosphite, 2,2-methylenebis (4,6-di- tert-butylphenyl) octyl phosphite and the like. Specific examples of such organic phosphite compounds include, for example, “ADEKA STAB 1178”, “ADEKA STAB 2112”, “ADEKA STAB HP-10” manufactured by ADEKA, “JP-351” manufactured by Johoku Chemical Industry Co., Ltd., “ JP-360 ”,“ JP-3CP ”,“ Irgaphos 168 ”manufactured by BASF, and the like.
In addition, 1 type may contain phosphorus stabilizer and 2 or more types may contain it by arbitrary combinations and a ratio.

  The content of the phosphorus stabilizer is usually 0.001 parts by mass or more, preferably 0.01 parts by mass or more, more preferably 0.03 parts by mass or more, with respect to 100 parts by mass of the polycarbonate resin (A). Moreover, it is 1 mass part or less normally, Preferably it is 0.7 mass part or less, More preferably, it is 0.5 mass part or less. If the content of the phosphorus stabilizer is less than or equal to the lower limit of the range, the thermal stability effect may be insufficient, and if the content of the phosphorus stabilizer exceeds the upper limit of the range, the effect May stop and become economical.

[Phenolic stabilizer]
The polycarbonate resin composition of the present invention preferably contains a phenol-based stabilizer. As a phenol type stabilizer, a hindered phenol type antioxidant is mentioned, for example. Specific examples thereof include pentaerythritol tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl). ) Propionate, thiodiethylenebis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], N, N′-hexane-1,6-diylbis [3- (3,5-di-) tert-butyl-4-hydroxyphenylpropionamide), 2,4-dimethyl-6- (1-methylpentadecyl) phenol, diethyl [[3,5-bis (1,1-dimethylethyl) -4-hydroxyphenyl ] Methyl] phosphoate, 3,3 ′, 3 ″, 5,5 ′, 5 ″ -hexa-tert-butyl-a, a ′, a ″-(mesi Tylene-2,4,6-triyl) tri-p-cresol, 4,6-bis (octylthiomethyl) -o-cresol, ethylenebis (oxyethylene) bis [3- (5-tert-butyl-4- Hydroxy-m-tolyl) propionate], hexamethylenebis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], 1,3,5-tris (3,5-di-tert- Butyl-4-hydroxybenzyl) -1,3,5-triazine-2,4,6 (1H, 3H, 5H) -trione, 2,6-di-tert-butyl-4- (4,6-bis ( Octylthio) -1,3,5-triazin-2-ylamino) phenol, 2- [1- (2-hydroxy-3,5-di-tert-pentylphenyl) ethyl] -4,6-di-te t- pentylphenyl acrylate.

Among them, pentaerythritol tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate preferable. Specific examples of such a phenolic antioxidant include “Irganox 1010”, “Irganox 1076” manufactured by BASF, “Adekastab AO-50”, “Adekastab AO-60” manufactured by ADEKA, and the like. Is mentioned.
In addition, 1 type may be contained for the phenol type stabilizer, and 2 or more types may be contained by arbitrary combinations and ratios.

  The content of the phenol-based stabilizer is usually 0.001 part by mass or more, preferably 0.01 part by mass or more, and usually 1 part by mass or less, preferably 100 parts by mass of the polycarbonate resin (A). 0.5 parts by mass or less. When the content of the phenolic stabilizer is not more than the lower limit of the above range, the effect as the phenolic stabilizer may be insufficient, and the content of the phenolic stabilizer exceeds the upper limit of the above range. If this is the case, the effect may reach its peak and not economical.

[Release agent]
Moreover, it is also preferable that the polycarbonate resin composition of this invention contains a mold release agent (lubricant). Examples of the release agent include aliphatic carboxylic acids, esters of aliphatic carboxylic acids and alcohols, aliphatic hydrocarbon compounds having a number average molecular weight of 200 to 15,000, polysiloxane silicone oils, and the like.

  Examples of the aliphatic carboxylic acid include saturated or unsaturated aliphatic monovalent, divalent or trivalent carboxylic acid. Here, the aliphatic carboxylic acid includes alicyclic carboxylic acid. Among these, preferable aliphatic carboxylic acids are monovalent or divalent carboxylic acids having 6 to 36 carbon atoms, and aliphatic saturated monovalent carboxylic acids having 6 to 36 carbon atoms are more preferable. Specific examples of such aliphatic carboxylic acids include palmitic acid, stearic acid, caproic acid, capric acid, lauric acid, arachidic acid, behenic acid, lignoceric acid, serotic acid, mellicic acid, tetrariacontanoic acid, montanic acid, adipine Examples include acids and azelaic acid.

  As aliphatic carboxylic acid in ester of aliphatic carboxylic acid and alcohol, the same thing as the said aliphatic carboxylic acid can be used, for example. On the other hand, examples of the alcohol include saturated or unsaturated monohydric or polyhydric alcohols. These alcohols may have a substituent such as a fluorine atom or an aryl group. Among these, monovalent or polyvalent saturated alcohols having 30 or less carbon atoms are preferable, and aliphatic saturated monohydric alcohols or aliphatic saturated polyhydric alcohols having 30 or less carbon atoms are more preferable. Here, the term “aliphatic” is used as a term including alicyclic compounds.

  Specific examples of such alcohols include octanol, decanol, dodecanol, stearyl alcohol, behenyl alcohol, ethylene glycol, diethylene glycol, glycerin, pentaerythritol, 2,2-dihydroxyperfluoropropanol, neopentylene glycol, ditrimethylolpropane, dipentaerythritol, and the like. Is mentioned.

  In addition, said ester may contain aliphatic carboxylic acid and / or alcohol as an impurity. Moreover, although said ester may be a pure substance, it may be a mixture of a plurality of compounds. Furthermore, the aliphatic carboxylic acid and alcohol which combine and comprise one ester may each be used 1 type, and may use 2 or more types together by arbitrary combinations and a ratio.

  Specific examples of esters of aliphatic carboxylic acids and alcohols include beeswax (a mixture based on myricyl palmitate), stearyl stearate, behenyl behenate, stearyl behenate, glycerin monopalmitate, glycerin monostearate Examples thereof include rate, glycerol distearate, glycerol tristearate, pentaerythritol monopalmitate, pentaerythritol monostearate, pentaerythritol distearate, pentaerythritol tristearate, pentaerythritol tetrastearate and the like.

  Examples of the aliphatic hydrocarbon having a number average molecular weight of 200 to 15,000 include liquid paraffin, paraffin wax, microwax, polyethylene wax, Fischer-Tropsch wax, and α-olefin oligomer having 3 to 12 carbon atoms. Here, the aliphatic hydrocarbon includes alicyclic hydrocarbons. Further, these hydrocarbons may be partially oxidized.

Among these, paraffin wax, polyethylene wax, or a partial oxide of polyethylene wax is preferable, and paraffin wax and polyethylene wax are more preferable.
The number average molecular weight of the aliphatic hydrocarbon is preferably 5,000 or less.
The aliphatic hydrocarbon may be a single substance, but even a mixture of various constituent components and molecular weights can be used as long as the main component is within the above range.

  Examples of the polysiloxane silicone oil include dimethyl silicone oil, methylphenyl silicone oil, diphenyl silicone oil, and fluorinated alkyl silicone.

  In addition, 1 type may contain the release agent mentioned above, and 2 or more types may contain it by arbitrary combinations and a ratio.

  The content of the release agent is usually 0.001 parts by mass or more, preferably 0.01 parts by mass or more, and usually 2 parts by mass or less, preferably 1 with respect to 100 parts by mass of the polycarbonate resin (A). It is below mass parts. When the content of the release agent is not more than the lower limit of the above range, the effect of releasability may not be sufficient, and when the content of the release agent exceeds the upper limit of the above range, hydrolysis resistance And mold contamination during injection molding may occur.

[Flame retardants]
The polycarbonate resin composition of the present invention preferably contains a flame retardant.
Flame retardants include halogenated bisphenol A polycarbonate, brominated bisphenol epoxy resin, brominated bisphenol phenoxy resin, halogenated flame retardant such as brominated polystyrene, phosphazene flame retardant, organometallic salt flame retardant, polyorgano Siloxane-based flame retardants and the like can be mentioned. Among these, organometallic salt-based flame retardants that hardly deteriorate the heat resistance of the polycarbonate resin are preferable.

  The organic metal salt flame retardant is preferably an organic sulfonic acid metal salt, particularly preferably a fluorine-containing aliphatic sulfonic acid metal salt or an aromatic sulfonic acid metal salt, and particularly preferably an aromatic sulfonic acid metal salt.

  The metal of the aromatic sulfonic acid metal salt is preferably an alkali metal or an alkaline earth metal. Examples of the alkali metal and alkaline earth metal include sodium, lithium, potassium, rubidium, cesium, beryllium, magnesium, calcium, strontium, and barium. Of these, sodium and potassium are preferable as the alkali metal, and magnesium, calcium and cesium are preferable as the alkaline earth metal from the viewpoint of compatibility with the polycarbonate resin and flame retardancy, and the aromatic sulfonic acid metal salt is 2 It may be a mixture of seeds or more.

  Examples of aromatic sulfonic acid metal salts include sodium diphenylsulfone-3-sulfonate, potassium diphenylsulfone-3-sulfonate, sodium 4,4′-dibromodiphenyl-sulfone-3-sulfone, 4,4′-dibromodiphenyl -Sulfone-3-sulfone potassium, 4-chloro-4'-nitrodiphenylsulfone-3-sulfonate calcium, diphenylsulfone-3,3'-disulphonate disodium, diphenylsulfone-3,3'-dipotassium disulfonate Can be mentioned. Among them, sodium dodecylbenzene sulfonate, sodium styrene sulfonate, etc. are mentioned as examples of non-halogen aromatic sulfonic acid metal salts. Among them, sodium paratoluene sulfonate or para-toluene in terms of flame retardancy, thermal stability and handling. Potassium sulfonate is preferred.

[Other ingredients]
The polycarbonate resin composition of the present invention may contain other components in addition to those described above as necessary, as long as the desired physical properties are not significantly impaired. Examples of other components include resins other than polycarbonate resins and various resin additives. In addition, 1 type may contain other components and 2 or more types may contain them by arbitrary combinations and ratios.

Other resins Examples of the other resins include thermoplastic polyester resins such as polyethylene terephthalate resin, polytrimethylene terephthalate, and polybutylene terephthalate resin;
Styrenic resin such as polystyrene resin, high impact polystyrene resin (HIPS), acrylonitrile-styrene copolymer (AS resin); polyolefin resin such as polyethylene resin and polypropylene resin; polyamide resin; polyimide resin; polyetherimide resin; Polyphenylene ether resin; polyphenylene sulfide resin; polysulfone resin; polymethacrylate resin and the like.
In addition, 1 type may contain other resin and 2 or more types may contain it by arbitrary combinations and a ratio.

-Resin additives Examples of resin additives include flame retardant aids (anti-dripping agents), UV absorbers, dyes and pigments, antistatic agents, antifogging agents, antiblocking agents, fluidity improvers, plasticizers, and dispersions. Agents, antibacterial agents and the like. In addition, 1 type may contain resin additive and 2 or more types may contain it by arbitrary combinations and a ratio.

  The polycarbonate resin composition of the present invention is excellent in heat resistance and has a high deflection temperature under load (DTUL). The measurement of high deflection temperature under load (DTUL) is based on ISO75-1 and is performed under the condition of 1.8 MPa, and the detailed conditions are as described in the examples. While the polycarbonate resin composition of the present invention contains a low molecular weight polycarbonate resin (A1) having a viscosity average molecular weight of 4000 to 10,000, the value of deflection temperature under load is preferably 105 ° C. or higher, more preferably 107 ° C. or higher. Holds the value of.

[Production of polycarbonate resin composition]
There is no restriction | limiting in the method of manufacturing the polycarbonate resin composition of this invention, The manufacturing method of a well-known polycarbonate resin composition can be employ | adopted widely.
Specific examples include polycarbonate resin (A1), polycarbonate resin (A2), titanium oxide (B) and core / shell type elastomer (C), and other components blended as necessary, such as tumbler or Examples thereof include a method of mixing in advance using various mixers such as a Henschel mixer and then melt-kneading with a mixer such as a Banbury mixer, roll, Brabender, single-screw kneading extruder, twin-screw kneading extruder, kneader.

Further, for example, it is possible to produce a polycarbonate resin composition without mixing each component in advance or by mixing only a part of the components in advance and supplying the mixture to an extruder using a feeder and melt-kneading. .
Also, for example, by mixing a part of the components in advance and supplying the resulting mixture to an extruder and melt-kneading it as a master batch, this master batch is again mixed with the remaining components and melt-kneaded. A polycarbonate resin composition can also be produced.
In addition, for example, when mixing a component that is difficult to disperse, the component that is difficult to disperse is dissolved or dispersed in a solvent such as water or an organic solvent in advance, and kneaded with the solution or the dispersion. It can also improve sex.

[Molding]
In order to produce a molded article from the polycarbonate resin composition of the present invention, a molding method generally adopted for the polycarbonate resin composition can be arbitrarily adopted. For example, injection molding method, ultra-high speed injection molding method, injection compression molding method, two-color molding method, hollow molding method such as gas assist, molding method using heat insulating mold, rapid heating mold were used. Molding method, foam molding (including supercritical fluid), insert molding, IMC (in-mold coating molding) molding method, extrusion molding method, sheet molding method, thermoforming method, rotational molding method, laminate molding method, press molding method, Examples thereof include a blow molding method, and a molding method using a hot runner method can also be used. Of these, injection molding methods such as injection molding, ultra-high speed injection molding, and injection compression molding are preferred.

Since the polycarbonate resin composition of the present invention is excellent in fluidity, in particular, thin-wall fluidity, it can be thinned to a level of 1 mm or less, and a thin-walled molded article having a thin-walled portion with a thickness of the thinnest portion of 1 mm or less. It can be. The thickness of the thinnest part is preferably 0.8 mm or less, more preferably 0.6 mm or less, and the upper limit of the thickness of the thinnest part is usually 0.1 mm or more, preferably 0.2 mm or more. It is. As a molded product having a thin portion, it is sufficient that the thin portion has a thickness of 1 mm or less at least partially, and there is no limitation on the shape, dimensions, and the like.
In addition, a thin-walled molded product in which the thin-walled portion constitutes the hinge portion of the molded product is also possible, and the hinge portion is excellent in bending resistance.

  Examples of molded products include parts such as electrical / electronic equipment, OA equipment, information terminal equipment, machine parts, home appliances, vehicle parts, building members, various containers, leisure goods / miscellaneous goods, and lighting equipment. Among these, it is particularly suitable for use in parts such as electrical and electronic equipment, OA equipment, information terminal equipment, home appliances, and lighting equipment, and particularly suitable for use in parts such as electrical and electronic equipment.

Examples of the electric / electronic devices include display devices such as personal computers, game machines, televisions, and electronic paper, printers, copiers, scanners, fax machines, electronic notebooks and PDAs, electronic desk calculators, electronic dictionaries, cameras, and videos. Cameras, mobile phones, smartphones, tablet terminals, touch panel terminals, battery packs for these, recording medium drives and reading devices, mice, numeric keys, CD players, MD players, portable radio / audio players, etc. .
Especially, it can be conveniently used as a reflective frame or reflector for various liquid crystal display devices.

Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not construed as being limited to the following examples.
In the following description, “parts” means “parts by mass” based on mass standards unless otherwise specified.
Each component used in Examples and Comparative Examples is as shown in Table 1 below.

(Examples 1 to 3 , 5 , 7 to 10, Reference Examples 4 and 6, Comparative Examples 1 to 9)
[Production of resin pellets]
Each component described in Table 1 was blended in the proportions (mass ratios) described in Tables 2 to 4 below, mixed for 20 minutes with a tumbler, and then a twin-screw extruder manufactured by Nippon Steel Works, Ltd. equipped with 1 vent ( TEX30HSST), kneaded under the conditions of a screw rotation speed of 250 rpm, a discharge rate of 25 kg / hour, and a barrel temperature of 260 ° C., the molten resin extruded into a strand is rapidly cooled in a water tank, pelletized using a pelletizer, and polycarbonate A pellet of the resin composition was obtained.

[Preparation of test piece]
The pellets obtained by the above production method were dried at 120 ° C. for 5 hours for those not using phosphate ester (D), and 5 hours at 100 ° C. for those using phosphate ester, and then Sumitomo Heavy Industries An ISO multipurpose test piece (3 mm thickness and 4 mm thickness) is injection molded under the conditions of a cylinder temperature of 280 ° C. and a mold temperature of 80 ° C. using an injection molding machine manufactured by Kogyo Co., Ltd. (Cycap M-2, clamping force 75T). did.
Moreover, the pellet obtained by said manufacturing method was dried at 120 degreeC for 5 hours about the thing which does not use phosphate ester (D), and 5 hours at 100 degreeC about the thing which uses phosphate ester (D). Thereafter, a two-stage plate having both a thickness of 3 mm and a thickness of 1 mm was injection molded under the conditions of a cylinder temperature of 280 ° C. and a mold temperature of 80 ° C. using a J55 type injection molding machine manufactured by Nippon Steel.

[Evaluation of fluidity by bar flow measurement]
The pellets obtained by the above production method were dried at 120 ° C. for 5 hours for those not using phosphate ester (D), and after 5 hours at 100 ° C. for those using phosphate ester (D), An injection molding machine manufactured by Nippon Steel Co., Ltd. (clamping force 55T) and a mold having a spiral resin flow part, a thickness of 1 mm and a width of 6 mm, a cylinder temperature of 280 ° C., an injection speed of 200 mm / s, Molding was performed under the conditions of an injection pressure upper limit of 100 MPa and a mold temperature of 80 ° C., and the flow length (unit: mm) was measured.
In the table, it is expressed as “fluidity (flow length)”.

[Charpy impact test]
Using ISO multi-purpose test piece (3mm thickness) obtained by the above method, conforming to ISO 179, R = 0.25 V notch, notched Charpy impact strength (unit: kJ) / M ² ) was measured.
In the table, “Charpy impact” is indicated.

[Light reflectivity evaluation]
The reflectance of the 3 mm thick part of the two-stage plate was measured. Using a spectrocolorimeter (CM3600d) manufactured by Konica Minolta, the light source was set to D65, the field of view was set to 10 degrees, and the reflectance (unit:%) at a wavelength of 440 nm was measured in the SCI normal measurement mode.
In the table, it is expressed as “light reflectivity (reflectance)”.

[Light shielding evaluation (total light transmittance)]
Using an NDH4000 turbidimeter manufactured by Nippon Denshoku Industries Co., Ltd., the total light transmittance (unit:%) of a 1 mm thick part of the two-stage plate was measured according to JIS K7361-1. The smaller the total light transmittance, the better the light shielding property.
In the table, it is expressed as “light shielding property (total light transmittance)”.

[Hue]
Using a SE6000 type color difference meter manufactured by Nippon Denshoku Industries Co., Ltd., setting the light source as the C light source and the field of view at 2 degrees, YI (Yellow Index) at the center of the two-stage plate (3 mm thick part) obtained by the above method Was measured. It means that the smaller the YI, the better the hue.
In the table, “Hue (YI)” is indicated.

[Heat resistance evaluation (DTUL)]
Using the 4 mm thick ISO multipurpose test piece obtained by the above method, the deflection temperature under load (DTUL, unit: ° C.) was measured under the condition of load 1.80 MPa (Method A) according to ISO 75-1 & 2. .
In the table, “heat resistance (DTUL)” is indicated.

[Bending resistance test]
The pellets obtained by the above production method were dried at 120 ° C. for 5 hours for those not using phosphate ester (D), and at 100 ° C. for 5 hours for those using phosphate ester (D), Using a J55 type injection molding machine manufactured by Nippon Steel Co., Ltd., injection molding was performed under conditions of a cylinder temperature of 280 ° C. and a mold temperature of 80 ° C., and a test for a bending resistance test with a length of 125 mm, a width of 13 mm and a thickness of 0.8 mm. A piece was molded.
Using this test piece, using an MIT folding resistance tester manufactured by Ueshima Seisakusho, in accordance with JIS P8115, with a load of 1.5 kgf, a mounting clamp R = 0.38 mm, an angle of 135 °, and a speed of 175 cpm. The number of reciprocal bendings until breakage (unit: times, 1 reciprocation = 1 time) was counted.
In the table, it is expressed as “number of bending test fractures”.
The above evaluation results are shown in Tables 2 to 6 below.

  The polycarbonate resin composition of the present invention has both high fluidity and impact resistance, is excellent in light reflectivity, light shielding properties, hue and heat resistance, and is also excellent in thin-wall moldability and bending resistance. It can be suitably used for applications requiring light reflectivity and light shielding properties, such as a light reflection plate and a light reflection frame of a display device, and LED lighting, and industrial applicability is very high.

Claims (6)

5 to 20 parts by mass of titanium oxide (B) with respect to 100 parts by mass of the polycarbonate resin (A), an acrylic rubber polymer as a core layer, and an acrylic polymer or copolymer component around the shell layer as a shell layer 1 to 10 parts by mass of the core / shell type elastomer (C) to be used, and the polycarbonate resin (A) is 5 to 50% by mass of the polycarbonate resin (A1) having a viscosity average molecular weight of 4,000 to 10,000 and a viscosity average molecular weight of 13,000 to 30,000. A polycarbonate resin composition comprising 50 to 95% by mass of a polycarbonate resin (A2). Based on ISO75-1, the value of the deflection temperature under load measured under the condition of 1.8 MPa is 10
The polycarbonate resin composition according to claim 1, which is 5 ° C or higher.   A molded article formed by molding the polycarbonate resin composition according to claim 1. The molded product according to claim 3, wherein the thickness of the thinnest part is 0.1 mm or more and 0.6 mm or less.   The molded article according to claim 4, which is a liquid crystal display device reflection frame.   The molded article according to claim 4, which is a liquid crystal display device reflector.