JP5068004B2 - Molded body of thermoplastic resin composition with white appearance and excellent light-shielding properties - Google Patents

Description

  The present invention relates to a molded body made of a thermoplastic resin having a white appearance and a high light shielding property. Furthermore, the present invention relates to a molded article having a white appearance and excellent light-shielding properties, which are excellent in mechanical strength, color tone stability, flame retardancy and the like.

Molded articles made of a resin composition in which titanium oxide is blended with a thermoplastic resin are widely used as materials for housings having a white appearance, sheets, films, or molded articles having a light reflecting function.
In particular, a resin composition obtained by blending aromatic polycarbonate with titanium oxide has a high whiteness, is excellent in light reflectivity, and has excellent dimensional stability, impact resistance, or heat resistance. Therefore, it is also used for display lamps such as guide lights and advertisement lights, and reflectors for backlight units for liquid crystal displays.
Recently, due to demands for a wide variety of designs, there has been an increasing demand for molded bodies for housings that have a light-shielding property while having a white appearance. For example, in a liquid crystal projector, there is a demand for a white housing molded body that does not leak light from the periphery of a light source section and has less fading due to heat or light (that is, excellent color tone stability).
In order to increase the whiteness of the thermoplastic resin and improve the light-shielding property, a method of incorporating titanium oxide is common, but recent examples relating to the aromatic polycarbonate resin composition include Patent Documents 1 to 4 and the like. be able to.

However, when it is intended to obtain a molded article having excellent whiteness and sufficient light-shielding properties only by blending titanium oxide, it is necessary to blend a large amount of titanium oxide, and when the blending amount of titanium oxide increases, Since chemically active sites exist on the surface of titanium oxide, this may promote deterioration of the resin during melt kneading and melt molding.
In addition, with regard to light shielding properties, there is a problem that a sufficient effect cannot be obtained even if a large amount of titanium oxide is blended, and light leakage occurs.
In particular, aromatic polycarbonates have a problem that the melt stability during molding is greatly reduced due to the blending of a large amount of titanium oxide. That is, there is a problem that the blending of a large amount of titanium oxide not only lowers the molecular weight of the aromatic polycarbonate, but also generates silver during molding and tends to cause poor appearance. Furthermore, blending a large amount of titanium oxide makes the molded body very brittle, making it difficult to maintain sufficient strength as a product. There was a problem of discoloration.
On the other hand, resin composition moldings used for OA equipment and electrical / electronic equipment often require high flame retardancy at the same time, and recently, brominated flame retardants or phosphorus-based flame retardants are environmentally friendly. There is a need for flame retardant resin composition molded bodies that do not use a flame retardant.

JP 2003-183491 A JP 2003-213114 A JP 2003-213144 A JP 2003-226805 A

  The present invention is a molded article made of a thermoplastic resin having a white appearance and a high light-shielding property, and also has a white appearance with improved properties such as mechanical strength, color stability and flame retardancy. It is an object of the present invention to provide a molded article having a high light shielding property.

As a result of intensive studies, the present inventors have found that 3 to 30 parts by weight of titanium oxide (B), dye / pigment (excluding component (B)) (C) 0.0001 per 100 parts by weight of the thermoplastic resin (A) A molded product comprising a resin composition containing ˜0.1 parts by weight, wherein the resin composition constituting the molded product has an L ^* value measured according to JIS-Z-8722 of 80 or more, and The above object is achieved by a molded article characterized in that the total light transmittance (T) [unit:%] at a thickness of 2 mm measured according to JIS-K-7105 is 0.1% or less. As a result, the inventors have found out that the present invention can be achieved.

That is, the present invention includes the following [1] to [3].
[1] 6 to 12 parts by weight of titanium oxide (B), dye / pigment (excluding component (B)) with respect to 100 parts by weight of aromatic polycarbonate or resin (A) mainly composed of aromatic polycarbonate (C) 0.0001-0.1 part by weight, aromatic condensed phosphate ester flame retardant (D) 12-30 part by weight, fluoropolymer (E) 0.01-1 part by weight, silicate compound (however, “50-200 (Excluding layered silicates having a cation exchange capacity of milliequivalents / 100 g)) (F) 3
A molded product comprising a resin composition containing 10 parts by weight, wherein the resin composition constituting the molded product has an L ^* value of 85 or more measured according to JIS-Z-8722, and JIS The total light transmittance (T) [unit:%] at a thickness of 2 mm measured according to -K-7105 is 0.1% or less, and the molded product has a light source part or a heat source part. A molded body, which is a housing member.
(Here, the resin mainly composed of aromatic polycarbonate means that when the total amount of component (A) is 100 parts by weight, the component exceeding 50 parts by weight of component (A) is aromatic polycarbonate, and the rest (Indicates that the resin component is a thermoplastic resin other than aromatic polycarbonate.)
[2] The molded body according to [1], wherein the molded body is an injection molded body or an extrusion molded body.
[3] The molded body according to [1] or [2], wherein the molded body is a housing member for a liquid crystal projector.

  The molded body made of a thermoplastic resin having a white appearance and a high light-shielding property according to the present invention has a particularly high white appearance as a molded body for various electric / electronic devices and OA devices having a light source part. It is extremely useful for applications that require light-shielding properties and excellent discoloration resistance, and has very high industrial significance.

The molded product of the present invention is characterized by having a “white appearance”. The “white appearance” as used in the present invention is an L * value (brightness) determined by a spectral colorimetry method (JIS-Z-8722). Is 80 or more, preferably 82 or more, more preferably 85 or more, and particularly preferably 87 or more. When the L * value is less than 80, it is insufficient to satisfy the “white appearance” that is the object of the present invention.
Furthermore, in this invention, the resin composition which comprises a molded object has a total light transmittance (T) [unit:%] in thickness 2mm measured according to JIS-K-7105 at 0.1% or less. Preferably, the total light transmittance at a thickness of 1.5 mm is 0.1% or less, more preferably the total light transmittance at a thickness of 1.0 mm is 0.1% or less. When the L * value and the total light transmittance satisfy the requirements of the present invention, the object of the present invention can be achieved.

The present invention will be specifically described below.
In the present invention, the component (A) is a thermoplastic resin, for example, polycarbonate resin, polystyrene resin, polymethacrylate resin, styrene / methacrylate copolymer, ABS resin, polyester resin, polyolefin resin, polyarylate. Resin, polyvinyl chloride resin, polyamide resin, polyphenylene ether resin, polyphenylene sulfide resin, etc., or a mixture of two or more of them can be used.
In the present invention, the component (A) is most preferably an aromatic polycarbonate resin or a resin mainly composed of an aromatic polycarbonate from the viewpoints of whiteness, heat resistance, light resistance, heat discoloration, dimensional stability, rigidity, and impact resistance. It can be preferably used.
Here, the resin mainly composed of aromatic polycarbonate means that when the total amount of component (A) is 100 parts by weight, the component exceeding 50 parts by weight of component (A) is aromatic polycarbonate, and the remaining resin The component is a thermoplastic resin other than the aromatic polycarbonate.
The aromatic polycarbonate preferably used as the component (A) of the present invention is an aromatic polycarbonate derived from an aromatic dihydroxy compound. Examples of the aromatic dihydroxy compound include 1,1-bis (4-hydroxy-t -Butylphenyl) propane, bis (hydroxyaryl) alkanes such as 2,2-bis (4-hydroxyphenyl) propane, 1,1-bis (4-hydroxyphenyl) cyclopentane, 1,1-bis (4- Bis (hydroxyaryl) cycloalkanes such as hydroxyphenyl) cyclohexane, dihydroxyaryl ethers such as 4,4′-dihydroxydiphenyl ether, 4,4′-dihydroxy-3,3′-dimethylphenyl ether, 4,4′- Dihydroxydiphenyl sulfide, 4,4 -Dihydroxyaryl sulfides such as dihydroxy-3,3'-dimethylphenyl sulfide, dihydroxyaryl sulfoxides such as 4,4'-dihydroxydiphenyl sulfoxide, 4,4'-dihydroxy-3,3'-dimethylphenyl sulfoxide, 4 , 4'-dihydroxydiphenylsulfone, dihydroxyarylsulfones such as 4,4'-dihydroxy-3,3'-dimethylphenylsulfone, and the like.
Among these, 2,2-bis (4-hydroxyphenyl) propane (common name, bisphenol A) is particularly preferable. These aromatic dihydroxy compounds can be used alone or in combination of two or more.

As the aromatic polycarbonate preferably used as the component (A) of the present invention, those produced by a known method can be used. Specifically, a known method of reacting an aromatic dihydroxy compound and a carbonate precursor, for example, reacting an aromatic dihydroxy compound and a carbonate precursor (for example, phosgene) in the presence of an aqueous sodium hydroxide solution and a methylene chloride solvent. Interfacial polymerization method (for example, phosgene method), transesterification method (melting method) for reacting aromatic dihydroxy compound and carbonic acid diester (for example, diphenyl carbonate), crystallization carbonate prepolymer obtained by phosgene method or melting method Solid phase polymerization [Japanese Unexamined Patent Publication No. 1-158033 (corresponding to US Pat. No. 4,948,871), Japanese Unexamined Patent Publication No. 1-271426, Japanese Unexamined Patent Publication No. 3-68627 (US Pat. No. 5,204) , No. 377))] and the like can be used. That.
Particularly preferred as the aromatic polycarbonate used as the component (A) of the present invention is substantially free of chlorine atoms produced by a transesterification method from a dihydric phenol (aromatic dihydroxy compound) and a carbonic acid diester. Aromatic polycarbonate.
The weight average molecular weight (Mw) of the aromatic polycarbonate is usually 5,000 to 500,000, preferably 10,000 to 100,000, more preferably 13,000 to 50,000, and particularly preferably. Is 15,000 to 30,000, particularly preferably 17,000 to 25,000.

In the present invention, the weight average molecular weight (Mw) of the aromatic polycarbonate can be measured using gel permeation chromatography (GPC), and the measurement conditions are as follows.
That is, it is obtained by using a converted molecular weight calibration curve according to the following formula from the composition curve of standard monodisperse polystyrene using polystyrene gel with tetrahydrofuran as a solvent.
M _pc = 0.3591M _ps ^1.0388
(M _pc is the molecular weight of aromatic polycarbonate, M _ps is the molecular weight of polystyrene)
Moreover, it is also a preferable embodiment that the aromatic polycarbonate preferably used as (A) of the present invention is a combination of two or more aromatic polycarbonates having different molecular weights. For example, an aromatic polycarbonate of an optical disk material whose Mw is usually in the range of 14,000 to 16,000, and an aromatic for injection molding or extrusion molding whose Mw is usually in the range of 20,000 to 50,000. A combination of polycarbonates can also be used.
Examples of the thermoplastic resin other than the aromatic polycarbonate that can be preferably used in the resin mainly composed of the aromatic polycarbonate include polystyrene, high impact polystyrene (HIPS), acrylonitrile-styrene resin (AS resin), and butyl acrylate. -Acrylonitrile-styrene resin (BAAS resin), acrylonitrile-butadiene-styrene resin (ABS resin), methyl methacrylate-butadiene-styrene resin (MBS resin), butyl acrylate-acrylonitrile-styrene resin (AAS resin), polyethylene terephthalate and polybutylene Examples thereof include polyester resins such as terephthalate, thermoplastic resins such as polyamide resin, polymethyl methacrylate, and polyarylate. In particular, AS resin and BAAS resin are preferable for improving fluidity, ABS resin and MBS resin are preferable for improving impact resistance, and polyester resin is preferable for improving chemical resistance.

In the present invention, the titanium oxide used as component (B) is not limited by the production method, crystal structure and particle size, but is titanium oxide produced by the chlorine method, and has a rutile crystal structure. What is taken is preferred.
Generally, the average particle size of titanium oxide used as a pigment is 0.1 to 0.4 μm, but the component (B) used in the present invention may have a particle size of less than 0.1 μm. .
The titanium oxide used in the present invention is preferably one that has been surface treated with one or more inorganic surface treatment agents selected from alumina hydrate and silicic acid hydrate. More preferably, in addition to the inorganic surface treatment, titanium oxide treated with an organic surface treatment agent is more preferred. The surface-treated titanium oxide is preferable because the molecular weight reduction and discoloration of the base resin can be suppressed when the resin composition is melt-kneaded at a high temperature.
Examples of the organic surface treatment agent include organopolysiloxanes such as alkylpolysiloxane, alkylarylpolysiloxane, and alkylhydrogenpolysiloxane, and organosilicones such as alkylalkoxysilane and amino silane coupling agents. Preferred treatment agents include methyl hydrogen polysiloxane, methyltrimethoxysilane, trimethylmethoxysilane, N-β (aminoethyl) -γ-aminopropyltrimethoxysilane, N-β (aminoethyl) -γ-aminopropylmethyl. Examples include dimethoxysilane. The surface treatment agent may contain a stabilizer, a dispersant and the like in an amount that does not inhibit the present invention. Further, as a surface treatment method, titanium oxide and a surface treatment agent are dispersed in water or an organic solvent and wet-treated, or a dry-treatment method using a super mixer, a hensil mixer, or the like, or a surface treatment agent and titanium oxide. Also effective are a method in which the thermoplastic resin as component (A) is simultaneously mixed in a V-type blender, and a method in which the thermoplastic resin is simultaneously introduced into an extruder and melt-kneaded.
The amount of titanium oxide (B) that can be used in the present invention is 3 to 30 parts by weight, preferably 4 to 20 parts by weight, more preferably 5 to 15 parts by weight, based on 100 parts by weight of the thermoplastic resin (A). Parts, particularly preferably 6 to 12 parts by weight. When the blending ratio of titanium oxide is less than 3 parts by weight, the light-shielding property becomes insufficient. On the other hand, when it exceeds 30 parts by weight, the impact strength of the resin composition is greatly decreased, which is not preferable.

The component (C) that can be used in the present invention is a dye / pigment. In the present invention, the dye / pigment represents a pigment or dye that can be used for coloring a thermoplastic resin.
Since the molded article of the present invention is a molded article having a white appearance and high light shielding properties, the amount of component (C) used is extremely small. However, in the present invention, by using a combination of an extremely small amount of the component (C) in addition to the component (B), a molded product with significantly improved light shielding properties can be obtained.
Specific examples of such component (C) include inorganic pigments such as titanium yellow, petal, ultramarine, cobalt blue, and spinel green, condensed azo organic pigments, quinacdolin organic pigments, isoindolinone organic pigments, and perylene organics. Pigments, organic pigments such as anthraquinone organic pigments, phthalocyanine organic pigments, carbon black, perylene dyes, coumarin dyes, thioindigo dyes, anthraquinone dyes, thioxanthone dyes, perinone dyes, quinoline dyes, quinacridone And organic dyes such as dyes, dioxazine dyes, isoindolinone dyes and phthalocyanine dyes.
In this invention, a component (C) can also be used in combination of 2 or more type.
The amount of component (C) in the present invention is 0.0001 to 0.1 parts by weight, preferably 0.0002 to 0.1 parts by weight, and 0.0005 to 100 parts by weight of component (A). 0.01 part by weight is more preferable, 0.001 to 0.005 part by weight is further preferable, and 0.002 to 0.001 part by weight is particularly preferable.
When the amount of the component (C) used is less than 0.0001 part by weight, the light shielding property is insufficient. On the other hand, when it exceeds 0.1 part by weight, it is difficult to maintain the white appearance of the molded product. It becomes.

Component (D) used in the present invention is a flame retardant, and represents a flame retardant that can be used for flame retardant thermoplastic resins.
Examples of the component (D) used in the present invention include organic phosphorus compounds (mainly phosphates and phosphazenes), organopolysiloxanes, halogen-containing compounds, metal oxides, metal hydroxides, triazine compounds, red phosphorus, zirconium compounds, Examples thereof include polyphosphate compounds, sulfamic acid compounds, and organic metal sulfonic acid alkali metal salts.
Although the compounding quantity of the component (D) in this invention changes according to the kind of flame retardant to be used, and the level of required flame retardance, it is 0.001 with respect to 100 weight part of component (A) normally. 30 parts by weight, preferably 0.01 to 20 parts by weight, more preferably 0.05 to 15 parts by weight, still more preferably 0.08 to 10 parts by weight.
In the present invention, an aromatic polycarbonate can be most preferably used as the component (A). However, when the component (A) is an aromatic polycarbonate, those that can be preferably used as the component (D) are organic acid alkali metal salts and It is at least one organic acid metal salt selected from organic acid alkaline earth metal salts.
Such an organic acid metal salt is a metal salt of an organic sulfonic acid and / or a metal salt of a sulfate, and these can be used alone or in combination of two or more.
Examples of the alkali metal contained in the organic acid metal salt include lithium, sodium, potassium, rubidium, and cesium, and examples of the alkaline earth metal include beryllium, magnesium, calcium, strontium, and barium.
In the present invention, particularly preferred alkali metals are lithium, sodium and potassium, and most preferably sodium and potassium.

Examples of the metal salts of organic sulfonic acids that can be preferably used in the present invention include alkali / alkaline earth metal salts of aliphatic sulfonic acids, alkali / alkaline earth metal salts of aromatic sulfonic acids, and the like. In the present specification, the term “alkali / alkaline earth metal salt” is used to include both alkali metal salts and alkaline earth metal salts.
Alkali / alkaline earth metal salts of aliphatic sulfonic acids include alkali / alkaline earth metal salts of alkane sulfonic acids having 1 to 8 carbon atoms, or alkyl groups of alkali / alkaline earth metal salts of such alkane sulfonic acids. Alkali / alkaline earth metal salts of sulfonic acids partially substituted with fluorine atoms, and further alkali / alkaline earth metal salts of perfluoroalkanesulfonic acids having 1 to 8 carbon atoms can be preferably used. Preferable specific examples include perfluoroethanesulfonic acid sodium salt and perfluorobutanesulfonic acid potassium salt.
In addition, as the alkali / alkaline earth metal salt of aromatic sulfonic acid, as aromatic sulfonic acid, monomeric or polymeric aromatic sulfide sulfonic acid, aromatic carboxylic acid and its ester sulfonic acid, monomeric or Polymeric aromatic ether sulfonic acid, aromatic sulfonate sulfonic acid, monomeric or polymeric aromatic sulfonic acid, monomeric or polymeric aromatic sulfonesulfonic acid, aromatic ketone sulfonic acid, heterocyclic An aromatic sulfonate alkali / alkaline earth metal salt having an aromatic sulfonic acid as at least one selected from the group consisting of a sulfonic acid, a sulfonic acid of an aromatic sulfoxide, and a condensate of an aromatic sulfonic acid by a methylene type bond Can be mentioned.
Preferred examples of the monomeric or polymeric aromatic sulfonic acid alkali / alkaline earth metal salts include diphenyl sulfide-4,4′-disulfonic acid disodium and diphenyl sulfide-4,4′-disulfone. Mention may be made of dipotassium acid.

Preferred examples of the sulfonic acid alkali / alkaline earth metal salts of the aromatic carboxylic acids and esters thereof include potassium 5-sulfoisophthalate, sodium 5-sulfoisophthalate, and polysodium poly (ethylene terephthalate). be able to.
The monomeric or polymeric aromatic ether sulfonate alkali / alkaline earth metal salt is, as a preferred example thereof, 1-methoxynaphthalene-4-calcium sulfonate, 4-sodium dodecylphenyl ether disulfonate, Poly (2,6-dimethylphenylene oxide) polysodium sulfonate, poly (1,3-phenylene oxide) polysodium sulfonate, poly (1,4-phenylene oxide) polysodium sulfonate, poly (2,6-diphenyl) Phenylene oxide) polypotassium polysulfonate, lithium poly (2-fluoro-6-butylphenylene oxide) polysulfonate.
Moreover, the sulfonate alkali / alkaline earth metal salt of the said aromatic sulfonate can mention the potassium sulfonate of benzenesulfonate as the preferable example.
The monomeric or polymeric aromatic sulfonic acid alkali / alkaline earth metal salts are preferably sodium benzenesulfonate, potassium benzenesulfonate, strontium benzenesulfonate, magnesium benzenesulfonate, p-benzene. Examples include dipotassium disulfonate, dipotassium naphthalene-2,6-disulfonate, calcium biphenyl-3,3′-disulfonate, sodium toluenesulfonate, potassium toluenesulfonate, and potassium xylenesulfonate.
The monomeric or polymeric aromatic sulfonesulfonic acid alkali / alkaline earth metal salts include, as preferred examples, sodium diphenylsulfone-3-sulfonate, potassium diphenylsulfone-3-sulfonate, and diphenylsulfone-3. , 3′-disulfonic acid dipotassium, diphenylsulfone-3,4′-disulfonic acid dipotassium.

Preferred examples of the sulfonate alkali / alkaline earth metal salt of the aromatic ketone include sodium α, α, α-trifluoroacetophenone-4-sulfonate and dipotassium benzophenone-3,3′-disulfonate. Can do.
Preferred examples of the heterocyclic alkali sulfonate / alkaline earth metal salt include disodium thiophene-2,5-disulfonate, dipotassium thiophene-2,5-disulfonate, and calcium thiophene-2,5-disulfonate. And sodium benzothiophene sulfonate.
Preferred examples of the aromatic sulfonate alkali / alkaline earth metal salt of aromatic sulfoxide include potassium diphenyl sulfoxide-4-sulfonate.
Preferred condensates of the above aromatic sulfonate alkali / alkaline earth metal salt by methylene type bond include a formalin condensate of sodium naphthalene sulfonate and a formalin condensate of sodium anthracene sulfonate.

On the other hand, as the alkali / alkaline earth metal salt of a sulfate ester, a monovalent and / or polyhydric alcohol sulfate / alkaline earth metal salt can be preferably used in the present invention. As sulfates of polyhydric alcohols, methyl sulfate, ethyl sulfate, lauryl sulfate, hexadecyl sulfate, polyoxyethylene alkylphenyl ether sulfate, pentaerythritol mono, di, tri, tetrasulfate And sulfuric acid ester of lauric acid monoglyceride, sulfuric acid ester of palmitic acid monoglyceride, and sulfuric acid ester of stearic acid monoglyceride. Particularly preferable alkali / alkaline earth metal salts of these sulfates include alkali / alkaline earth metal salts of lauryl sulfate.
Examples of other alkali / alkaline earth metal salts include alkali sulfonamide alkali / alkaline earth metal salts such as saccharin, N- (p-tolylsulfonyl) -p-toluenesulfonimide. N- (N′-benzylaminocarbonyl) sulfanilimide, and alkali / alkaline earth metal salts of N- (phenylcarboxyl) sulfanilimide, and the like.
Among the enumerated above, more preferable alkali / alkaline earth metal salts include alkali / alkaline earth metal salts of aromatic sulfonic acid and alkali / alkaline earth metal salts of perfluoroalkanesulfonic acid.
In the present invention, when the component (A) is an aromatic polycarbonate, at least one organic acid metal salt selected from the organic acid alkali metal salts and organic acid alkaline earth metal salts that can be preferably used as the component (D). The amount used is usually 0.001 to 1 part by weight, preferably 0.005 to 0.8 part by weight, and more preferably 0.01 to 0.7 part by weight with respect to 100 parts by weight of the component (A). 0.03-0.5 part by weight is more preferred, 0.05-0.3 part by weight is particularly preferred, and 0.06-0.2 part by weight is most preferred.

Component (E) that can be used in the present invention is a fluoropolymer, and is used for the purpose of preventing dripping of combustion products. The component (E) that can be preferably used in the present invention is a fluoropolymer having a fibril-forming ability, and a tetrafluoroethylene polymer such as polytetrafluoroethylene or a tetrafluoroethylene / propylene copolymer is preferably used. Particularly preferred is polytetrafluoroethylene.
As the component (E), various forms of fluoropolymers such as a fine powdery fluoropolymer, an aqueous dispersion of fluoropolymer, and a powdery mixture with a second resin such as AS or PMMA can be used.
As an aqueous dispersion of a fluoropolymer that can be preferably used in the present invention, “Teflon 30J (registered trademark)” manufactured by Mitsui DuPont Fluorochemical Co., Ltd., “Polyflon D-1 (registered trademark)” manufactured by Daikin Industries, Ltd., “Polyfluorocarbon” Examples thereof include “D-2 (registered trademark)”, “Polyflon D-2C (registered trademark)”, and “Polyflon D-2CE (registered trademark)”.
In the present invention, a fluoropolymer in a powdery mixture with a second resin such as AS or PMMA can also be suitably used as the component (E). Techniques relating to the fluoropolymer as a mixture are disclosed in JP-A-9-95583 (corresponding to US Pat. No. 5,804,654) and JP-A-11-49912 (US Pat. No. 6,040,370). , JP 2000-143966 A, JP 2000-297189 A, and the like. Fluoropolymers in a powdery mixture with these second resins that can be preferably used in the present invention include “Blendex 449 (registered trademark)” manufactured by GE Specialty Chemicals Co., Ltd., “Metablene A-3800” manufactured by Mitsubishi Rayon Co., Ltd. Registered trademark) ”.
When using a component (E) in this invention, the compounding quantity is 0.01-1 weight part normally with respect to 100 weight part of components (A), Preferably it is 0.05-0.8 weight part. More preferably, it is 0.1-0.6 weight part, More preferably, it is 0.1-0.4 weight part. When the usage-amount of a component (E) exceeds 1 weight part, it exists in the tendency for the surface appearance of a molded object to fall.

In the present invention, an aromatic polycarbonate can be most preferably used as the component (A). However, when the component (A) is an aromatic polycarbonate, it is more preferable to include a silicate compound (component (F)).
Such a silicate compound is a silicate compound comprising a metal oxide component and a SiO ₂ component. The silicate compound that can be used as the component (F) may be in any form such as orthosilicate, disilicate, cyclic silicate, chain silicate, layered silicate, etc.
The “silicate compound” may be any compound of a complex oxide, an oxyacid salt, and a solid solution, and the complex oxide is a combination of two or more of a single oxide, and a single oxide and an oxyacid salt. The solid solution may be either a solid solution of two or more metal oxides or a solid solution of two or more oxyacid salts. The “silicate compound” may be a hydrate.
The “silicate compound” may be a natural product or an artificial synthetic product. As the artificial compound, silicate compounds obtained from various conventionally known methods, for example, various synthesis methods using a solid reaction, a hydrothermal reaction, an ultrahigh pressure reaction, and the like can be used.
The silicate compound particularly preferably used as the component (F) of the present invention preferably has a composition substantially represented by the following formula (1).
_{xMO · ySiO 2 · zH 2 O} (1)
(Here, x and y represent natural numbers, z represents an integer of 0 or more, MO represents a metal oxide component, and may be a plurality of metal oxide components.)
Examples of the metal M in the metal oxide MO include potassium, sodium, lithium, barium, calcium, zinc, manganese, iron, cobalt, magnesium, zirconium, aluminum, and titanium.
In the metal oxide MO, preferred is one that substantially contains either CaO or MgO. Further preferred is the case where the metal oxide MO consists essentially of at least one component selected from CaO and MgO, and particularly preferred is the case consisting essentially of MgO.

Specific examples of the silicate compound preferably used as the component (F) of the present invention include talc, mica, wollastonite, zonotlite, kaolin clay, montmorillonite, bentonite, sepiolite, imogolite, sericite, lawsonite, smectite, and the like. Can be listed.
The “silicate compound” can be of any shape (plate, needle, granular, fiber, etc.), but is preferably plate or needle, and in particular, plate Are most preferably used as the component (F) of the present invention.
Here, the plate-like form means that when the average particle diameter is (a) and the thickness is (c), the a / c ratio is 5 to 500, preferably 10 to 300, more preferably 20 to 200. It is of shape.
The needle-like form means that the a / c ratio is 5 to 500, preferably 10 to 10 when the average particle diameter in the major axis direction is (a) and the average particle diameter in the uniaxial direction is (c). 300, more preferably 20-200.
In the present invention, the average particle size of the component (F) is preferably 0.1 to 500 μm, more preferably 0.5 to 100 μm, further preferably 1 to 50 μm, particularly preferably 2 to 30 μm, most preferably 3 to 20 μm. preferable.
The average particle size referred to in the present invention is determined by a laser diffraction method (for example, using SALD-2000 manufactured by Shimadzu Corporation).
Among the silicate compounds that can be used as the component (F) of the present invention, talc and mica are particularly preferable.
Talc that can be particularly preferably used as the component (F) of the present invention is a hydrous magnesium silicate having a layered structure, represented by the chemical formula 4SiO ₂ .3MgO.H ₂ O, usually about 63 wt% SiO ₂ , It contains about 32% MgO, about 5% by weight H ₂ O, other Fe ₂ O ₃ , CaO, Al ₂ O _{3 and the} like, and has a specific gravity of about 2.7.
In addition, as the talc that can be particularly preferably used as the component (F) of the present invention, calcined talc, talc that has been washed with an acid such as hydrochloric acid or sulfuric acid to remove impurities, and the like can be preferably used. Furthermore, talc that has been subjected to surface hydrophobic treatment with a silane coupling agent, a titanate coupling agent, or the like can also be used.

On the other hand, mica which can be particularly preferably used as the component (F) of the present invention is a pulverized product of silicate mineral containing aluminum, potassium, magnesium, sodium, iron and the like. Mica includes muscovite (mascobite, chemical formula: K (AlSi ₃ O ₁₀ ) (OH) ₂ Al ₄ (OH) ₂ (AlSi ₃ O ₁₀ ) K), phlogopite (phlogopite, chemical formula: K (AlSi ₃ O ₁₀₎ ) (OH) ₂ Mg ₆ (OH) ₂ (AlSi ₃ O ₁₀ ) K), biotite (biotite, chemical formula: K (AlSi ₃ O ₁₀ ) (OH) ₂ (Mg, Fe) ₆ (OH) ₂ ( AlSi ₃ O ₁₀ ) K), artificial mica (fluorine phlogopite, chemical formula: K (AlSi ₃ O ₁₀ ) (OH) ₂ F ₂ Mg ₆ F ₂ (AlSi ₃ O ₁₀ ) K) Any mica can be used, but muscovite is preferred.
Such mica may be subjected to surface hydrophobic treatment with a silane coupling agent, a titanate coupling agent, or the like.
When using a component (F) in this invention, the usage-amount is 0.1-30 weight part normally with respect to 100 weight part of component (A), 0.5-25 weight part is preferable, 1 -20 parts by weight is more preferable, 2-15 parts by weight is still more preferable, and 3-10 parts by weight is particularly preferable.
Furthermore, when using the said component (F) in this invention, it is preferable to use together an organic acidic compound and / or an organic acidic compound derivative (component (G)).

Specifically, the component (G) that can be preferably used in the present invention is an organic acid derivative selected from organic acids and / or organic acid esters, organic acid anhydrides, organic acid phosphonium salts, and organic acid ammonium salts. Can be mentioned.
In the present invention, by using a combination of component (F) and component (G), the flame retardancy and melt stability of the resin composition can be dramatically improved.
In addition, when the component (F) is used in the present invention, the amount of the component (G) used relative to the component (F) is extremely important, and even if the amount of the component (G) is too small relative to the component (F) Even if it exists, it becomes difficult to obtain the melt stability and color tone stability of the resin composition.
The “organic acid” is an organic compound containing at least one group selected from the group consisting of —SO ₃ H group, —COOH group, and —POH group in the molecular structure, ie, organic sulfonic acid, organic carboxylic acid, Organic phosphoric acid. Of these, organic sulfonic acids and organic carboxylic acids are preferred in the present invention, and organic sulfonic acids are particularly preferred.
The “organic acid derivative” represents an organic acid ester, an organic acid anhydride, an organic acid phosphonium salt, or an organic acid ammonium salt derived from the organic acid.
The “organic acid derivative (G) selected from organic acids and / or organic acid esters, organic acid anhydrides, organic acid phosphonium salts, and organic acid ammonium salts” is not only a low molecular weight compound, but also an oligomeric or polymeric material. Things can be used.
In the present invention, two or more components (G) can be used in combination.
As component (G) of the present invention, organic sulfonic acid derivatives and organic carboxylic acids selected from organic sulfonic acids and / or organic sulfonic acid esters, organic sulfonic acid phosphonium salts, and organic sulfonic acid ammonium salts are particularly preferably used. it can.
Among them, when an organic sulfonic acid or organic sulfonic acid ester is used as the component (G), the melt stability of the resin composition is particularly excellent, and the generation of volatile components can be suppressed to a low level. The molding process can be performed in the temperature range and the appearance of the molded product is extremely excellent.

As the organic sulfonic acid that can be preferably used as the component (G) of the present invention, benzenesulfonic acid, p-toluenesulfonic acid, xylenesulfonic acid, naphthalenesulfonic acid, diisopropylnaphthalenesulfonic acid, diisobutylnaphthalenesulfonic acid, dodecylbenzene Examples include aromatic sulfonic acids such as sulfonic acids, aliphatic sulfonic acids having 8 to 18 carbon atoms, sulfonated polystyrene, polymers such as methyl acrylate / sulfonated styrene copolymers, and oligomeric organic sulfonic acids. Can do.
Examples of the organic sulfonic acid ester that can be used as the component (G) of the present invention include methyl benzenesulfonate, ethyl benzenesulfonate, propyl benzenesulfonate, butyl benzenesulfonate, octyl benzenesulfonate, and phenyl benzenesulfonate. , Methyl p-toluenesulfonate, ethyl p-toluenesulfonate, propyl p-toluenesulfonate, butyl p-toluenesulfonate, octyl p-toluenesulfonate, phenyl p-toluenesulfonate, methyl naphthalenesulfonate, naphthalenesulfone Ethyl acetate, propyl naphthalenesulfonate, butyl naphthalenesulfonate, 2-phenyl-2-propyl dodecylbenzenesulfonate, 2-phenyl-2-butyl dodecylbenzenesulfonate, etc. It can be.
Examples of the organic sulfonic acid phosphonium salt that can be used as the component (G) of the present invention include octylsulfonic acid tetrabutylphosphonium salt, decylsulfonic acid tetrabutylphosphonium salt, benzenesulfonic acid tetrabutylphosphonium salt, and dodecylbenzenesulfonic acid. Examples thereof include tetraethylphosphonium salt, tetrabutylphosphonium dodecylbenzenesulfonate, tetrahexylphosphonium dodecylbenzenesulfonate, tetraoctylphosphonium dodecylbenzenesulfonate, and the like.
Examples of the organic sulfonic acid ammonium salt that can be used as the component (G) of the present invention include decyl ammonium butyl sulfate, decyl ammonium decyl sulfate, dodecyl ammonium methyl sulfate, dodecyl ammonium ethyl sulfate, dodecyl methyl ammonium methyl sulfate, and dodecyl dimethyl. Ammonium tetradecyl sulfate, tetradecyl dimethyl ammonium methyl sulfate, tetramethyl ammonium hexyl sulfate, decyl trimethyl ammonium hexadecyl sulfate, tetrabutyl ammonium dodecyl benzyl sulfate, tetraethyl ammonium dodecyl benzyl sulfate, tetramethyl ammonium dodecyl benzyl sulfate, etc. Door can be.

Furthermore, in the present invention, the organic sulfonic acid preferably used as the component (G) includes an —OH group, —NH ₂ group, —COOH group, halogen group, etc. in addition to —SO ₃ H group in the molecular structure. For example, naphthol sulfonic acid, sulfamyl acid, naphthylamine sulfonic acid, sulfobenzoic acid, fully substituted or partially substituted chloro group-containing organic sulfonic acid, fully substituted or partially substituted fluoro group Examples thereof include organic sulfonic acids.
As the component (G) used in the present invention, an aromatic sulfonic acid compound is particularly preferable, and benzenesulfonic acid, p-toluenesulfonic acid, naphthalenesulfonic acid, and the like can be given as the most preferable examples.
When using a component (G) in this invention, the usage-amount is 0.001-5 weight part normally with respect to 100 weight part of component (A), More preferably, 0.01- 3 parts by weight, more preferably 0.05 to 2 parts by weight, particularly preferably 0.1 to 1 part by weight.
The amount (parts by weight) of component (G) in the composition of the present invention is such that when the pH value of the mixture of component (F) and component (G) is measured based on JIS-K-5101, It is particularly preferable that the pH value of the mixture is in the range of 4 to 8 parts by weight.
That is, the optimal usage amount of the component (G) in the present invention varies depending on the type, shape and amount of the component (F) or the type of the component (F).
The amount of component (G) used is such that when the pH value of a mixture of component (F) and component (G) is measured based on JIS-K-5101, the pH value of the mixture is 4.2 to 7.8. More preferably, the number of parts by weight is in the range of 4.5 to 7.6, more preferably the number of parts by weight in the range of 5.0 to 7.4. Particularly preferred is the number of parts by weight in the range of 5.5 to 7.2.
In the measurement of the pH value of JIS-K-5105 according to the present invention, there are a boiling method and a room temperature method as an operation method, but the boiling method is used in the present invention.
In the measurement of the pH value of the mixture of component (F) and component (G) in the present invention, when the solubility of component (G) in water is low, alcohols such as ethanol and isopropyl alcohol are dispersed in the suspension. Used as a medium.

In this invention, it is preferable that the resin composition which comprises a molded object further contains an organic phosphorus stabilizer. By blending the organophosphorus compound, the thermal stability of the resin composition can be improved, and the color tone stability, moist heat resistance, heat discoloration resistance, and molding processing characteristics can be improved.
As such an organic phosphorus stabilizer, phosphate ester, phosphite ester, phosphonate ester and the like can be used.
Specific examples of the phosphate ester include tributyl phosphate, triethyl phosphate, trimethyl phosphate, triphenyl phosphate, diphenyl monooxoxenyl phosphate, dibutyl phosphate, dioctyl phosphate, and diisopropyl phosphate.
Specific examples of phosphites include triphenyl phosphite, tris (nonylphenyl) phosphite, tridecyl phosphite, trioctyl phosphite, trioctadecyl phosphite, didecyl monophenyl phosphite, dioctyl mono Phenyl phosphite, diisopropyl monophenyl phosphite, monobutyl diphenyl phosphite, monodecyl diphenyl phosphite, monooctyl diphenyl phosphite, tris (2,4-di-tert-butylphenyl) phosphite, bis (2,6- Di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite, 2,2-methylenebis (4,6-di-tert-butylphenyl) octyl phosphite, bis (nonylphenyl) pentaeryth Diphosphite, bis (2,4-di -tert- butylphenyl) pentaerythritol diphosphite can be exemplified distearyl pentaerythritol diphosphite.
Specific examples of the phosphonic acid ester include tetrakis (2,4-di-iso-propylphenyl) -4,4′-biphenylenediphosphonite, tetrakis (2,4-di-n-butylphenyl) -4. , 4′-biphenylenediphosphonite, tetrakis (2,4-di-tert-butylphenyl) -4,4′-biphenylenediphosphonite, tetrakis (2,4-di-tert-butylphenyl) -4,3 '-Biphenylenediphosphonite, tetrakis (2,4-di-tert-butylphenyl) -3,3'-biphenylenediphosphonite, tetrakis (2,6-di-iso-propylphenyl) -4,4'- Biphenylene diphosphonite, tetrakis (2,6-di-n-butylphenyl) -4,4′-biphenylene diphosphonite, tetrakis (2, 6-di-tert-butylphenyl) -4,4′-biphenylenediphosphonite, tetrakis (2,6-di-tert-butylphenyl) -4,3′-biphenylenediphosphonite, tetrakis (2,6- Di-tert-butylphenyl) -3,3′-biphenylenediphosphonite, bis (2,4-di-tert-butylphenyl) -biphenylphosphonite, dimethyl benzenephosphonate, diethylbenzenephosphonate, dipropylbenzenephosphonate Can be illustrated.
Of these, tris (2,4-di-tert-butylphenyl) phosphite and tetrakis (2,4-di-tert-butylphenyl) -4,4′-biphenylenediphosphonite are particularly preferable. And bis (2,4-di-tert-butylphenyl) -biphenylphosphonite.
The amount of the organophosphorus stabilizer used is usually preferably 0.001 to 0.5 parts by weight, more preferably 0.01 to 0.3 parts by weight, with respect to 100 parts by weight of the component (A), and 0.02 -0.2 weight part is further more preferable. Moreover, these organic phosphorus stabilizers may be used alone or in combination of two or more.

In this invention, the resin composition which comprises a molded object can contain a ultraviolet absorber further, and can thereby improve light resistance.
Examples of such ultraviolet absorbers include benzophenone-based ultraviolet absorbers represented by 2,2′-dihydroxy-4-methoxybenzophenone, 2- (4,6-diphenyl-1,3,5-triazin-2-yl)- Triazine-based ultraviolet absorbers typified by 5-hexyloxyphenol, 2- (2H-benzotriazol-2-yl) -4-methylphenol, 2- (2H-benzotriazol-2-yl) -4-tert- Octylphenol, 2- (2H-benzotriazol-2-yl) -4,6-bis (1-methyl-1-phenylethyl) phenol, 2- (2H-benzotriazol-2-yl) -4,6-di -Tert-pentylphenol, 2- (5-chloro-2H-benzotriazol-2-yl) -4-methyl-6-tert-butyl Phenol, 2- (5-chloro-2H-benzotriazol-2-yl) -2,4-tert-butylphenol and 2,2′-methylenebis [6- (2H-benzotriazol-2-yl) -4- ( 1,1,3,3-tetramethylbutyl) phenol] and the like are exemplified, and these may be used alone or in combination of two or more.
The amount of the ultraviolet absorber used is usually preferably 0.001 to 1 part by weight, more preferably 0.01 to 0.8 part by weight, and 0.05 to 0. 0 part by weight with respect to 100 parts by weight of the component (A). 5 parts by weight is more preferable.

In this invention, the resin composition which comprises a molded object can contain a fluorescent whitening agent further. The fluorescent whitening agent has an action of absorbing energy in the ultraviolet part of light and radiating this energy to the visible part, and can improve the color tone of the resin composition to white or bluish white.
Examples of such optical brighteners include stilbenzene, benzimidazole, benzoxazole, naphthalimide, rhodamine, coumarin, and oxazine compounds.
The amount of the fluorescent whitening agent used is usually preferably 0.0005 to 0.1 parts by weight, more preferably 0.001 to 0.05 parts by weight, and more preferably 0.003 to 100 parts by weight of the component (A). -0.03 weight part is still more preferable.
Moreover, in the resin composition which comprises the molded object of this invention, a lubricant, a mold release agent, antioxidant, an antistatic agent etc. can also be added as needed.

Next, the manufacturing method of the resin composition concerning this invention is demonstrated.
The resin composition according to the present invention can be obtained by blending each constituent component in the composition ratio described in the present specification and melt-kneading using a melt-kneading apparatus such as an extruder. At this time, blending of each component and melt kneading use a commonly used device, for example, a premixing device such as a tumbler or ribbon blender, a melt kneading device such as a single screw extruder, a twin screw extruder, or a kneader. I can do it. The raw materials can be supplied to the melt-kneading apparatus after mixing each component in advance, but it is also possible to supply each component independently to the melt-kneading apparatus.
As a melt-kneading apparatus for producing the resin composition according to the present invention, an extruder, preferably a twin-screw extruder is usually used. The melt-kneading can usually be carried out by appropriately setting the cylinder set temperature of the extruder to 200 to 300 ° C., preferably 220 to 270 ° C., and appropriately selecting the screw speed of the extruder from 100 to 700 rpm, preferably from 200 to 500 rpm. However, care should be taken not to give excessive heat during melt kneading. Furthermore, it is also effective to provide an opening in the latter part of the extruder and perform open devolatilization and, if necessary, vacuum devolatilization. Further, the residence time of the raw material resin in the extruder is usually selected appropriately within a range of 10 to 60 seconds.

The molding method for obtaining the molded product of the present invention is not particularly limited, and examples thereof include injection molding, extrusion molding, compression molding, rotational molding, blow molding, etc. Among them, injection molding and extrusion molding are preferably used.
When the molded product of the present invention is molded by injection molding, not only a normal molding method, but also injection compression molding, injection press molding, gas assist injection molding, foam molding (including those by supercritical fluid injection), A molded product can be obtained using an injection molding method such as insert molding, in-mold coating molding, heat-insulating mold molding, rapid heating / cooling mold molding, two-color molding, sandwich molding, or ultrahigh-speed injection molding. For injection molding, either a cold runner method or a hot runner method can be selected.
In the case of injection molding, as a special technique for increasing the fluidity of the resin, a method of improving the fluidity of the molten resin by dissolving nitrogen or carbon dioxide as a plasticizer in the molten resin may be used. Nitrogen and carbon dioxide may be appropriately injected by providing a vent portion in an injection molding machine cylinder. In order to improve transferability of molded products, or to prevent defects in appearance (swirl marks) when filling the mold with a resin in which nitrogen or carbon dioxide is dissolved in the molten resin, the molten resin is used as a mold. Before filling into the mold, the mold may be filled with nitrogen gas or carbon dioxide in advance. In this case, carbon dioxide is preferably used for the purpose of improving transferability.

Moreover, when shape | molding the molded object of this invention by extrusion molding. It can also be used in the form of various profile extrusion moldings, sheets, films and the like. For forming sheets and films, an inflation method, a calendar method, a casting method, or the like can be used.
When the molded article of the present invention is a sheet or film-like extruded molded article, the thickness is preferably 0.01 to 10 mm, more preferably 0.1 to 5 mm, still more preferably 0.15 to 3 mm, and 2 to 2 mm is particularly preferable.
Furthermore, the molded body comprising the aromatic polycarbonate resin composition of the present invention preferably achieves any flame retardancy of 5V, V-0, V-1 by a test method according to the UL94 standard, in particular 5V, It is preferable to achieve V-0.
The molded body of the present invention has an excellent white appearance and excellent light-shielding property, and various electrical / electronic equipment and OA equipment housing members having a light source part and a heat source part, especially an advanced white appearance and light-shielding property. It is extremely useful for applications requiring discoloration resistance, including liquid crystal projectors, copiers, printers, notebook computers, mobile phones, lighting equipment, signboards, reflectors, various electronic and electrical equipment, containers, miscellaneous goods, etc. It can be used in a wide variety of fields.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples.
In Examples or Comparative Examples, the following components were used to produce a thermoplastic resin composition.
1. Component (A): Thermoplastic resin (A-1) Aromatic polycarbonate Octadecyl-3 is a bisphenol A polycarbonate produced by melt transesterification from bisphenol A and diphenyl carbonate and used as a hindered phenol antioxidant. -300 ppm of-(3,5-di-t-butyl-4-hydroxyphenyl) propionate and 300 ppm of tris (2,4-di-t-butylphenyl) phosphite as a phosphite heat stabilizer Average molecular weight (Mw) = 20,800.
(A-2) Aromatic polycarbonate A bisphenol A-based polycarbonate produced from bisphenol A and diphenyl carbonate by the melt transesterification method, and octadecyl-3- (3,5-di-) as a hindered phenol-based antioxidant. 300 ppm of t-butyl-4-hydroxyphenyl) propionate and 500 ppm of tris (2,4-di-t-butylphenyl) phosphite as a phosphite heat stabilizer, weight average molecular weight (Mw) = 27, 200 things.
(A-3) Polymethylmethacrylate manufactured by Asahi Kasei Chemicals Corporation: Delpet 60N (registered trademark)

2. Component (B): Titanium oxide (B-1)
Rutile-type titanium dioxide produced by the sulfuric acid method, alumina-treated titanium dioxide having a primary average particle size of 0.22 μm (B-2)
2. Rutile-type titanium dioxide produced by a chlorine method, treated with alumina having a primary average particle size of 0.21 μm, and then surface-treated with methyl hydrogen polysiloxane. Component (C): Dyeing pigment (C-1)
“Mitsubishi Carbon No. 52 (registered trademark)” manufactured by Mitsubishi Chemical Corporation
(C-2)
Made by Bayer Corporation; “Macrolex Violet B (registered trademark)”
4). Ingredient (D): Flame retardant (D-1)
Perfluorobutanesulfonic acid potassium salt (“Mega-Fuck F114 (registered trademark)” manufactured by Dainippon Ink Industries, Ltd.)
(D-2)
Aromatic condensed phosphate ester ("PX-200 (registered trademark)" manufactured by Daihachi Chemical Co., Ltd.)

5. Component (E): Fluoropolymer (E-1)
50/50 (weight ratio) powdered mixture of polytetrafluoroethylene (PTFE) and polymethyl methacrylate (PMMA) (“Metbrene A-3800 (registered trademark)” manufactured by Mitsubishi Rayon Co., Ltd.)
6). Component (F): Silicate compound (F-1)
Made by Nippon Talc Co., Ltd. “Microace P3 (registered trademark)”
7). Component (G): Organic acidic compound and / or organic acidic compound derivative (G-1)
p-toluenesulfonic acid; manufactured by Wako Pure Chemical Industries, Ltd. Other ingredients:
(PETS)
Pentaerythritol tetrastearate (“Unistar H476 (registered trademark)” manufactured by NOF Corporation)

[Reference Examples 1 to 4, Example 5, Reference Example 6 and Comparative Examples 1 to 3]
Each component was melt kneaded in the amounts shown in Table 1 (units are parts by weight) using a twin screw extruder to obtain a resin composition.
Each component was premixed for 5 minutes in advance using a tumbler to obtain a powder raw material mixture. Thereafter, using a twin screw extruder (ZSK-25, L / D = 37, manufactured by Werner & Pfleiderer), melt kneading was performed under conditions of a cylinder set temperature of 250 ° C. and a screw rotation speed of 150 rpm.
The melt-kneaded resin composition is extruded into a strand shape and pelletized. A molded body was prepared using the obtained pellets and used for each evaluation.
The molded bodies of Reference Examples 1 to 4 and Example 5 were molded by injection molding.
The molded body of Reference Example 6 was obtained by drying pellets of the resin composition at 120 ° C. for 4 hours, and using a 65 mm single-screw extruder (GM65-25, manufactured by GM Engineering Co., Ltd.) equipped with a T-die, a cylinder set temperature of 270 ° C. The sheet was molded under the conditions of a screw rotation speed of 15 rpm and a discharge amount of 10 to 15 kg / hr. The T die had a slit width of 0.5 to 2.5 mm and a slit length of 380 mm. The sheet extruded from the T-die was adjusted by a roll in a range of roll rotation speed of 0.6 to 1.5 m / min to obtain a sheet having a desired thickness while balancing the discharge amount.

(1) L ^* measurement With an injection molding machine (auto shot 100D, manufactured by FANUC) set to a cylinder temperature of 280 ° C. and a mold temperature of 80 ° C., the thickness is 50 mm (width) × 90 mm (length), and the thickness is 3 mm. 3 mm plates of 2 mm and 1 mm were formed.
The L * value was measured using a spectrocolorimeter CM-2002 manufactured by Minolta Co., Ltd. with respect to the 2 mm thickness portion of the three-stage plate. The measurement conditions were D65 / 10 °.
About Example 6, it measured using the sheet | seat of thickness 2mm.
(2) Light-shielding property measurement All light transmission using the COLOR AND COLOR DIFFERENCE METER MODEL 1001DP by Nippon Denshoku Industries Co., Ltd. with respect to the thickness 2mm part and thickness 1mm part of the 3 step | paragraph plate used by the said L ^* measurement. Rate (T) [unit%] was measured.
About Example 6, it measured using the sheet | seat of thickness 2mm and 1mm.
Furthermore, using the multimedia projector “ELP-51” manufactured by Epson Corporation, with the light source turned on, the projection lens part is pressed against the 2 mm thick part of the three-stage plate to provide the following light shielding properties in the dark room: Visual judgment was made based on the evaluation criteria.
○: There is no light transmission and the light shielding property is good.
X: Light transmission is recognized.

(3) Heat-resistant discoloration The three-stage plate used in the L ^* measurement is held in an oven set at 100 ° C. for 100 hours, and the change in color difference (ΔE _ab ^* ) from the initial hue is measured. Judged.
○: ΔE _ab ^* is 1 or less.
X: ΔE _ab ^* exceeds 1.
(4) Flame retardance A strip-shaped molded product for a combustion test is molded by an injection molding machine and held in an environment of a temperature of 23 ° C. and a humidity of 50% for 2 days, and then a vertical combustion test is performed according to the UL94 standard. The specimen thicknesses shown in the table were classified into 5VB, V-0, V-1, and V-2.
The results are shown in Tables 1 and 2.

  The molded body of the present invention is a molded body having a white appearance and excellent light shielding properties, and is a housing member of various electric / electronic devices and OA devices having a light source part and a heat source part. Furthermore, it is extremely useful for applications that require excellent discoloration resistance, such as liquid crystal projectors, copiers, printers, notebook computers, mobile phones, lighting equipment, signboards, resin windows, various electronic and electrical equipment, containers, It can be used in various fields including miscellaneous goods and is useful.

Claims (3)

6 to 12 parts by weight of titanium oxide (B), dye / pigment (excluding component (B)) with respect to 100 parts by weight of aromatic polycarbonate or resin (A) mainly composed of aromatic polycarbonate (C) 0.0001 -0.1 part by weight, aromatic condensed phosphate ester flame retardant (D) 12-30 parts by weight, fluoropolymer (E) 0.01-1 part by weight, silicate compound (however, "50-200 meq / (Excluding layered silicate having a cation exchange capacity of 100 g)) (F) A molded article comprising a resin composition containing 3 to 10 parts by weight, wherein the resin composition constituting the molded article is JIS-Z- The L ^* value measured according to 8722 is 85 or more, and the total light transmittance (T) [unit:%] at a thickness of 2 mm measured according to JIS-K-7105 is 0.1. % Of the light source part. Molded body characterized by have is housing member of a product having a heat source unit.
(Here, the resin mainly composed of aromatic polycarbonate means that when the total amount of component (A) is 100 parts by weight, the component exceeding 50 parts by weight of component (A) is aromatic polycarbonate, and the rest (Indicates that the resin component is a thermoplastic resin other than aromatic polycarbonate.)   The molded body according to claim 1, wherein the molded body is an injection molded body or an extrusion molded body.   The molded body according to claim 1 or 2, wherein the molded body is a housing member for a liquid crystal projector.