TW202411346A - Aromatic polycarbonate resin composition - Google Patents

Abstract

Provided is an aromatic polycarbonate resin composition in which heat resistance and mechanical strength inherent in polycarbonate resin are not impaired, that has excellent thermal stability, high transparency, high light transmittance and high light diffusing properties, and that is less likely to cause deterioration in transparency and light transmittance. The aromatic polycarbonate resin composition includes: a linear aromatic polycarbonate resin (A), a polyether derivative (B), a light diffusing agent (C), a phosphorus antioxidant (D) and an aromatic compound (E) represented by the following Formula (1), wherein the aromatic polycarbonate resin composition includes, with respect to 100 parts by weight of the linear aromatic polycarbonate resin (A), 0.1 to 2.0 parts by weight of the polyether derivative (B), a 0.1 to 6.0 parts by weight of the light diffusing agent (C), up to 0.5 parts by weight of the phosphorus antioxidant (D), and up to 0.003 parts by weight of the aromatic compound (E).

Description

Aromatic polycarbonate resin composition and light diffusing molded product

The present invention relates to an aromatic polycarbonate resin composition and a light diffusing molded product.

Since polycarbonate resin has excellent impact resistance, heat resistance, and transparency, it has been used in molded products such as light guide plates, various lenses, and nameplates. Compared with light diffusing molded products made of acrylic resin, light diffusing molded products made of resin compositions in which light diffusing agents such as inorganic particles and polymer particles are mixed into aromatic polycarbonate resins have better heat resistance and dimensional stability. Therefore, they are used in a wide range of fields, such as lamp covers, meters, billboards (especially internal lighting), resin window glass, light diffusing plates for image reading devices or image display devices (such as light diffusing plates used in backlight modules of liquid crystal display devices, light diffusing plates used in projection type display screens such as projection televisions, etc.), and light diffusing films (such as high-transmittance light diffusing films used to increase the brightness of liquid crystal display devices, etc.).

As image display devices have become larger, thinner (lighter), more complex in shape, and more functional in recent years, there is an increasing demand for light diffusing molded products, especially light diffusing plates and films used in image display devices, to be larger, thinner (lighter), more complex in shape, and more functional, and aromatic polycarbonate resin compositions with excellent fluidity during molding are required.

Patent document 1 states that pentaerythritol ester compounds are added to reduce the molecular weight of aromatic polycarbonate resins by ester exchange to improve fluidity. [Prior art document] [Patent document]

[Patent Document 1] International Publication No. 2013/011977

(Invent the problem you want to solve)

However, the polycarbonate resin composition disclosed in Patent Document 1 still cannot fully meet the requirements for materials in recent years, such as the requirements for less reduction in transparency and light transmittance even when forming at high temperatures for thin-wall forming and the requirements for large-scale production.

Furthermore, light diffusing molded products (e.g., light diffusing plates for image display devices) used in automotive image display devices that have been formed and processed into thin sizes of about 0.3 mm in recent years are required to have little reduction in transparency and light transmittance even when exposed to high temperature conditions caused by light irradiation for an extremely long time. In other words, the light transmittance should not be reduced despite the large size, and the high light diffusing material should not be invisible due to the light source penetrating through it.

The purpose of the present invention is to provide: without damaging the original heat resistance and mechanical strength of polycarbonate resin, excellent thermal stability, high transparency, light transmittance, and light diffusion, and after forming into a thin large-scale molded product of about 0.3 mm (for example, a light diffusion plate for an image display device), even if it is exposed to high temperature conditions caused by light irradiation for a very long time, it is still not easy to reduce transparency and light transmittance (not easy to cause white turbidity and coloring), that is, even if it is large, the light transmittance is not reduced, and there is no high light diffusion aromatic polycarbonate resin composition that cannot be seen due to the penetration of light source. (Technical means to solve the problem)

The inventors of the present invention have conducted in-depth research to solve these problems and have found that an aromatic polycarbonate resin composition containing a predetermined amount of a linear aromatic polycarbonate resin, a polyether derivative (B) and a light diffuser (C) does not damage the original properties of the polycarbonate resin, such as heat resistance and mechanical strength, and has excellent thermal stability and high light transmittance. Even if a thin molded product (light guide plate) having a thickness of about 0.3 mm is exposed to high temperature conditions caused by light source irradiation for a long time, the transparency and transmittance are still slightly reduced (it is not easy to become cloudy or colored), thereby completing the present invention.

That is, the present invention provides an aromatic polycarbonate resin composition and a light diffusing molded product formed by molding the same, wherein the aromatic polycarbonate resin composition comprises: a linear aromatic polycarbonate resin (A), a polyether derivative (B), a light diffuser (C), a phosphorus antioxidant (D), and an aromatic compound (E) represented by the following formula (1); wherein, relative to 100 parts by weight of the linear aromatic polycarbonate resin (A), the polyether derivative (B) is contained in an amount of 0.1 to 2.0 parts by weight, the light diffuser (C) is contained in an amount of 0.1 to 6.0 parts by weight, the phosphorus antioxidant (D) is contained in an amount of up to 0.5 parts by weight, and the aromatic compound (E) is contained in an amount of up to 0.003 parts by weight. Formula (1): [Chemical 1] (Compared with the efficacy of previous technologies)

The polycarbonate resin composition of the present invention does not damage the heat resistance, mechanical strength and other properties originally possessed by the polycarbonate resin, and has excellent thermal stability, high transparency, light transmittance and light diffusion. Moreover, even if the obtained molded product is exposed to a hot weather environment and/or high temperature conditions caused by light source irradiation for an extremely long period of time, the transparency and transmittance are not easily reduced (white turbidity or coloration is not likely to occur). Therefore, even if it is a thin molded product (diffusion plate) with a thickness of about 0.3 mm, it is not easy to change the color and reduce the appearance (deterioration). Even if it is exposed to high temperature conditions caused by the external environment or light source for a long time, it is not easy to reduce the transparency (not easy to become cloudy or colored), that is, it will not cause the light transmittance to be reduced. In addition, a polycarbonate resin composition with high light diffusion that will not be invisible due to the penetration of light source can be provided, and the industrial utilization value is extremely high.

The following is a detailed description of the implementation form. However, sometimes more detailed descriptions than necessary are omitted. For example, detailed descriptions of known matters or repeated descriptions of substantially the same structure will be omitted. This is to avoid the following description being too lengthy so that people familiar with this technology can easily understand it.

In addition, the inventors provide the following description in order to enable those skilled in the art to fully understand the present invention, but it is not intended to limit the subject matter described in the patent application scope.

The aromatic polycarbonate resin composition of the embodiment of the present invention comprises: a linear aromatic polycarbonate resin (A), a polyether derivative (B), a light diffuser (C), and, if necessary, a phosphorus antioxidant (D) and/or a specific aromatic compound (E). The aromatic polycarbonate resin composition of the embodiment may further contain an epoxy compound and/or other components as required.

In the embodiment of the present invention, "linear aromatic polycarbonate resin (A)" is a polycarbonate resin based on an aromatic compound. As long as the aromatic polycarbonate resin composition for the purpose of the present invention can be obtained, there are no special restrictions on the rest. However, since branched aromatic polycarbonates will lead to reduced transparency and light transmittance, they are excluded from the scope of the present invention as much as possible. Linear aromatic polycarbonate resins can be exemplified by polymers obtained by the phosgene method of reacting various dihydroxy diaryl compounds with phosgene, or the ester exchange method of reacting dihydroxy diaryl compounds with carbonates such as diphenyl carbonate. Representative examples include polycarbonate resins made from 2,2-bis(4-hydroxyphenyl)propane (bisphenol A).

Examples of the dihydroxydiaryl compound include bisphenol A and bis(4-hydroxyphenyl)methane, 1,1-bis(4-hydroxyphenyl)ethane, 2,2-bis(4-hydroxyphenyl)butane, 2,2-bis(4-hydroxyphenyl)octane, bis(4-hydroxyphenyl)phenylmethane, 2,2-bis(4-hydroxyphenyl-3-methylphenyl)propane, 1,1-bis(4-hydroxy-3-tert-butylphenyl)propane, 2,2-bis(4-hydroxy-3-bromophenyl)propane, 2,2-bis(4-hydroxy-3,5-dibromophenyl)propane, and 2,2-bis(4-hydroxy-3,5-dichlorophenyl)propane. Bis(hydroxyaryl)alkanes such as 1,1-bis(4-hydroxyphenyl)cyclopentane and 1,1-bis(4-hydroxyphenyl)cyclohexane; dihydroxydiaryl ethers such as 4,4'-dihydroxydiphenyl ether and 4,4'-dihydroxy-3,3'-dimethyldiphenyl ether; 4,4'- Dihydroxydiaryl sulfides such as dihydroxydiphenyl sulfide; dihydroxydiaryl sulfides such as 4,4'-dihydroxydiphenyl sulfide and 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfide; dihydroxydiaryl sulfides such as 4,4'-dihydroxydiphenyl sulfide and 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfide. These can be used alone or in combination. In addition to these, piperidine, dipiperidinyl hydroquinone, resorcinol, 4,4'-dihydroxydiphenyl and the like can also be used in combination.

The viscosity average molecular weight of the linear aromatic polycarbonate resin (A) is preferably 10000 to 100000, more preferably 12000 to 30000. In addition, when producing such an aromatic polycarbonate resin (A), a molecular weight regulator, a catalyst, etc. may be used as necessary.

In the embodiment of the present invention, the so-called "polyether derivative (B)" refers to a derivative of a polyether compound, and is not particularly limited as long as the aromatic polycarbonate resin composition of the present invention can be obtained. Representative examples of such polyether derivatives include the polyether derivatives represented by the following formula (2).

Formula (2): RO-(X-O)m(Y-O)n-R' (wherein, R and R' represent independently hydrogen atoms or alkyl groups with 1 to 30 carbon atoms; X represents a linear or branched alkyl group with 2 to 4 carbon atoms; Y represents a linear or branched alkyl group with 2 to 5 carbon atoms; X and Y may be the same or different, m and n represent independently 3 to 60, and m+n is 6 to 12). The weight average molecular weight of the polyether derivative represented by formula (2) is preferably 500 to 8000, and more preferably 1000 to 4000. The polyether derivative represented by formula (2) may also be commercially available.

The polyether derivative represented by formula (2) may also be a compound represented by the following formula (2-1). Formula (2-1): RO-(X-O)m(Y-O)n-R' (In the formula, R and R' represent independently hydrogen atoms or alkyl groups with 1 to 30 carbon atoms; X represents a linear alkyl group with 2 to 4 carbon atoms; Y represents a branched alkyl group with 2 to 5 carbon atoms; m and n represent independently 3 to 60, and m+n is 8 to 90.) The weight average molecular weight of the polyether derivative represented by formula (2-1) is preferably 500 to 8000, and more preferably 1000 to 4000. The polyether derivative represented by formula (2-1) may also be commercially available.

The polyether derivative represented by formula (2) may also be a compound represented by the following formula (2-2). Formula (2-2): RO-(X-O)m(Y-O)n-R' (In the formula, R and R' represent independently hydrogen atoms or alkyl groups with 1 to 30 carbon atoms; X represents a linear alkyl group with 2 to 4 carbon atoms; Y represents a linear alkyl group with 2 to 5 carbon atoms; X and Y may be the same or different; m and n represent independently 3 to 60, and m+n is 6 to 100.) The weight average molecular weight of the polyether derivative represented by formula (2-2) is preferably 500 to 8000, and more preferably 1000 to 4000. The polyether derivative represented by formula (2-2) may also be commercially available.

The polyether derivative represented by formula (2) may also be a compound represented by the following formula (2-3). Formula (2-3): RO-(X-O)m(Y-O)n-R' (In the formula, R and R' represent independently hydrogen atoms or alkyl groups with 1 to 30 carbon atoms; X represents a branched alkyl group with 2 to 4 carbon atoms; Y represents a branched alkyl group with 2 to 5 carbon atoms; X and Y may be the same or different; m and n represent independently 3 to 60, and m+n is 6 to 120.) The weight average molecular weight of the polyether derivative represented by formula (2-3) is preferably 500 to 8000, and more preferably 1000 to 4000. The polyether derivative represented by formula (2-3) may also be commercially available.

The polyether derivative represented by formula (2) preferably contains at least one selected from the group consisting of a polyether derivative represented by formula (3), a polyether derivative represented by formula (4), a polyether derivative represented by formula (5), a polyether derivative represented by formula (6), a polyether derivative represented by formula (7), a polyether derivative represented by formula (8), a polyether derivative represented by formula (9), a polyether derivative represented by formula (10), and a polyether derivative represented by formula (11).

The polyether derivative represented by formula (2-1) preferably includes at least one selected from the group consisting of a polyether derivative represented by formula (3), a polyether derivative represented by formula (4), a polyether derivative represented by formula (5), a polyether derivative represented by formula (6), and a polyether derivative represented by formula (7).

The polyether derivative represented by formula (2-2) preferably contains at least one selected from the group consisting of the polyether derivative represented by formula (8) and the polyether derivative represented by formula (9).

The polyether derivative represented by formula (2-3) is preferably at least one selected from the group consisting of a polyether derivative represented by formula (10) and a polyether derivative represented by formula (11).

Formula (3): HO-(CH ₂ CH ₂ CH ₂ CH ₂ O)m(CH(CH ₃ )CH ₂ O)nH (In the formula, m and n are independently 3 to 60, and m+n is 8 to 90.)

The polyether derivative represented by formula (3) is preferably a modified diol containing a butanediol unit and a propylene glycol unit. Such polyether derivatives can be commercially available, for example, POLYCERIN DCB-1000 (weight average molecular weight 1000), POLYCERIN DCB-2000 (weight average molecular weight 2000), POLYCERIN DCB-4000 (weight average molecular weight 4000) manufactured by NOF Corporation. The weight average molecular weight of the polyether derivative represented by formula (3) is preferably 500 to 8000, more preferably 1000 to 4000.

Formula (4): HO-(CH ₂ CH ₂ CH ₂ CH ₂ O)m(CH ₂ CH ₂ CH(CH ₃ )CH ₂ O)nH (In the formula, m and n are independently 3 to 60, and m+n is 8 to 90.)

The polyether derivative represented by formula (4) is preferably a modified diol containing butanediol units and 2-methylbutanediol units. Such polyether derivatives can be commercially available, for example, PTG-L1000 (weight average molecular weight 1000), PTG-L2000 (weight average molecular weight 2000), or PTG-L3000 (weight average molecular weight 3000) manufactured by Hodogaya Chemical Industry Co., Ltd. The weight average molecular weight of the polyether derivative represented by formula (4) is preferably 500 to 8000, more preferably 1000 to 4000.

Formula (5): HO-(CH ₂ CH ₂ O)m(CH(CH ₃ )CH ₂ O)nH (In the formula, m and n are independently 3 to 60, and m+n is 8 to 90.)

The polyether derivative represented by formula (5) is preferably a modified diol containing ethylene glycol units and propylene glycol units. Such polyether derivatives can be commercially available, for example, UNILUB 50DE-25 (weight average molecular weight 1750), UNILUB 75DE-25 (weight average molecular weight 1400) manufactured by NOF Corporation, etc. The weight average molecular weight of the polyether derivative represented by formula (5) is preferably 500 to 8000, more preferably 1000 to 4000.

Formula (6): RO-(CH ₂ CH ₂ CH ₂ CH ₂ O)m(CH(CH ₃ )CH ₂ O)nH (wherein, R represents an alkyl group having 1 to 30 carbon atoms; m and n represent independently 3 to 60, and m+n is 8 to 90.)

The polyether derivative represented by formula (6) is preferably a modified diol containing a butylene glycol unit and a propylene glycol unit and having a butyl group at one end or a stearyl group at one end. Such a polyether derivative can be commercially available, for example, POLYCERIN BC-1000 (butyl group at one end, weight average molecular weight 1000) and POLYCERIN SC-1000 (stearyl group at one end, weight average molecular weight 1000) manufactured by NOF Corporation. The weight average molecular weight of the polyether derivative represented by formula (6) is preferably 500 to 8000, more preferably 1000 to 4000.

Formula (7): RO-(CH ₂ CH ₂ O)m(CH(CH ₃ )CH ₂ O)nH (wherein, R represents an alkyl group having 1 to 30 carbon atoms; m and n represent independently 3 to 60, and m+n is 8 to 90.)

The polyether derivative represented by formula (7) is preferably a modified diol containing ethylene glycol units and propylene glycol units and having a butyl group or a stearyl group at one end. Such polyether derivatives can be commercially available, for example, UNILUBE 50MB-11 (butyl group at one end, weight average molecular weight 1000), UNILUBE 50MB-26 (butyl group at one end, weight average molecular weight 2000), UNILUBE 50MB-72 (butyl group at one end, weight average molecular weight 3000), UNILUBE 10MS-250KB (stearyl group at one end, weight average molecular weight 2000) manufactured by NOF Corporation. The weight average molecular weight of the polyether derivative represented by formula (7) is preferably 500 to 8000, more preferably 1000 to 4000.

Formula (8): HO-(CH ₂ CH ₂ CH ₂ CH ₂ O)m(CH ₂ CH ₂ O)nH (In the formula, m and n are independently 3 to 60, and m+n is 8 to 90.)

The polyether derivative represented by formula (8) is preferably a modified diol containing a butanediol unit and an ethylene glycol unit. Such polyether derivatives can be commercially available, for example, POLYCERIN DC3000E (weight average molecular weight 3000), POLYCERIN DC1800E (weight average molecular weight 1800) manufactured by NOF Corporation, etc. The weight average molecular weight of the polyether derivative represented by formula (8) is preferably 500 to 8000, more preferably 1000 to 4000.

Formula (9): HO-(CH ₂ CH ₂ CH ₂ CH ₂ O)pH (wherein, p represents 6 to 100.)

The polyether derivative represented by formula (9) is preferably polytetramethylene glycol. Such polyether derivatives can be commercially available, for example, PTG-650SN (weight average molecular weight 650), PTG-850SN (weight average molecular weight 850), PTG-1000SN (weight average molecular weight 1000), PTG-1400SN (weight average molecular weight 1400), PTG-2000SN (weight average molecular weight 2000), or PTG-2900 (weight average molecular weight 2900) manufactured by Hodogaya Chemical Industry Co., Ltd. The weight average molecular weight of the polyether derivative (polytetramethylene glycol) represented by formula (9) is preferably 500 to 8000, more preferably 1000 to 4000.

Formula (10): Formula: HO-(CH(CH ₃ )CH ₂ O)qH (wherein, q represents 7 to 120.)

The polyether derivative represented by formula (10) is preferably polypropylene glycol. Such polyether derivatives can be commercially available, for example: Polyglycol P2000P (weight average molecular weight 2000) manufactured by Dow Chemical; UNIOL D-1000 (weight average molecular weight 1000), UNIOL D-2000 (weight average molecular weight 2000), UNIOL D-4000 (weight average molecular weight 4000) manufactured by NOF Corporation, etc. The weight average molecular weight of the polyether derivative (polypropylene glycol) represented by formula (10) is preferably 500 to 8000, more preferably 1000 to 4000.

Formula (11): HO-(CH(C ₂ H ₅ )CH ₂ O)rH (wherein r represents 6 to 100.)

The polyether derivative represented by formula (11) is preferably polybutylene glycol. Such polyether derivatives can be commercially available, for example, UNIOL PB-500 (weight average molecular weight 500), UNIOL PB-1000 (weight average molecular weight 1000), UNIOL PB-2000 (weight average molecular weight 2000) manufactured by NOF Corporation. The weight average molecular weight of the polyether derivative (polybutylene glycol) represented by formula (11) is preferably 500 to 8000, more preferably 1000 to 4000.

The polyether derivative represented by the general formula (2) above is generally highly heat-resistant, and a molded product obtained by molding an aromatic polycarbonate resin composition blended with the polyether derivative at a high temperature has high brightness and light transmittance.

Furthermore, each of the polyether derivatives represented by the above formulae (2) to (11) may contain repeating units other than the repeating units described in the formulae provided that the aromatic polycarbonate resin composition and optical molded article of the present invention can be obtained. Examples of such repeating units include repeating units based on impurities that may be contained in the starting materials of the polyether derivatives, repeating units based on an initiator used in polymerization (polymerization initiator), and the like.

When a polymerization initiator is used in the synthesis of the polyether derivative, the polymerization initiator may be exemplified by the following compounds: for example, hydrogenated bisphenol A, bisphenol A, isosorbide, glycerol, pentaerythritol, sorbitol, glucose, and the like.

A polyether derivative containing a repeating unit based on such a polymerization initiator may be used, for example, POLYCERIN 60DB-2000H (manufactured by NOF Corporation) represented by the following formula (3') (see formula 3-2). Formula (3'): [Chemical 2] (In the formula, m1+m2 corresponds to m in formula (3), and n1+n2 corresponds to n in formula (3).)

The weight average molecular weight of the polyether derivative represented by formula (3-2) is preferably 500 to 8000, more preferably 1000 to 4000.

Furthermore, since the polyether derivative (B) used in the present invention has a moderate lipophilicity, it has excellent miscibility with the aromatic polycarbonate resin (A), so that the transparency of the molded article obtained from the aromatic polycarbonate resin composition blended with the polyether derivative (B) is not reduced, and the transparency can be maintained. The weight average molecular weight of the polyether derivative (B) is preferably 500-8000, more preferably 1000-4000.

Furthermore, the CPR (unit: dimensionless) (Controlled Polymerization Rate, an index indicating the amount of alkaline substances in the polyether derivative, measured according to JIS K1557-4) of the polyether derivative (B) used in the present invention is preferably 2.0 or less, and more preferably 1.0 or less. If the CPR is 2.0 or less, the polyether derivative (B) has excellent miscibility with the polycarbonate resin, decomposition and degradation are suppressed, storage stability is excellent, and the hue of the obtained polycarbonate resin composition is not easily adversely affected. For example, the CPR of POLYCERIN DCB-2000 belonging to the polyether derivative (B) represented by the above formula (3) is less than 1.0, the CPR of POLYCERIN 60DB-2000H (manufactured by NOF Corporation) belonging to the polyether derivative (B) represented by the above formula (3) is less than 1.0, and the CPR of PTG-1000SN (manufactured by Hodogaya Chemical Industries, Ltd.) belonging to the polyether derivative (B) represented by the above formula (9) is less than 1.0.

Furthermore, the pH (measured in accordance with JIS K1557-5) of the polyether derivative (B) used in the present invention is preferably 5.0 or more and less than 7.5, and more preferably 6.0 or more and less than 7.0. When the pH of the polyether derivative (B) is 5.0 or more and less than 7.5, decomposition and degradation are suppressed, storage stability is excellent, and the hue of the obtained polycarbonate resin composition is unlikely to be adversely affected. For example, the pH of POLYCERIN DCB-2000 belonging to the polyether derivative (B) represented by the above formula (3) is 6.7, the pH of POLYCERIN 60DB-2000H (manufactured by NOF Corporation) belonging to the polyether derivative (B) represented by the above formula (3) is 6.8, and the pH of PTG-1000SN (manufactured by Hodogaya Chemical Industries, Ltd.) belonging to the polyether derivative (B) represented by the above formula (9) is 6.7.

Furthermore, the temperature at which the polyether derivative (B) used in the present invention becomes 90% by weight (or the temperature at which the weight reduction rate becomes 10%) (measured by thermogravimetric measurement in accordance with JIS K7120) is preferably 300° C. or higher, more preferably 330° C. or higher. When the temperature at which the polyether derivative (B) becomes 90% by weight is 300° C. or higher, decomposition and degradation are suppressed, storage stability is excellent, and the hue of the obtained polycarbonate resin composition is less likely to be adversely affected. For example, the temperature at which POLYCERIN DCB-2000 belonging to the polyether derivative (B) represented by the above formula (3) becomes 90% by weight is 330°C, and the temperature at which POLYCERIN 60DB-2000H (manufactured by NOF Corporation) belonging to the polyether derivative (B) represented by the above formula (3) becomes 90% by weight is 400°C.

The amount of the polyether derivative is 0.1 to 2.0 parts by weight, preferably 0.3 to 1.8 parts by weight, relative to 100 parts by weight of the aromatic polycarbonate resin (A). If the amount of the polyether derivative is less than 0.1 parts by weight, the light transmittance and hue enhancement effect are insufficient. On the contrary, if the amount of the polyether derivative exceeds 2.0 parts by weight, the atomization rate increases, resulting in a decrease in light transmittance.

In the embodiment of the present invention, the light diffuser (C) is not particularly limited, provided that it can scatter light in the polycarbonate resin composition, and the chemical composition such as polymer system and inorganic system is not particularly limited. However, when the light diffuser (C) is added to the linear polycarbonate resin (A) and dispersed by a known method such as melt mixing using an extruder, it must be in the form of particles that are not compatible with or difficult to be compatible with the matrix phase.

The light diffuser (C) is preferably a microparticle with light diffusing ability. Such microparticles include inorganic microparticles and polymer microparticles. Examples of inorganic microparticles include glass fillers, calcium carbonate, barium sulfate, silicon dioxide, talc, mica, silica, titanium oxide, etc. Among them, calcium carbonate is preferred. The shape of the inorganic microparticles is preferably granular (including amorphous) or plate-like rather than fibrous. For example, in the case of glass fillers, examples include glass beads, tiny hollow glass spheres, ground glass fibers, glass fragments, ultra-thin glass fragments (made by the sol-gel method), amorphous glass, etc. The same is true for other inorganic microparticles, and various shapes can be used.

From the perspective of light diffusion, polymer particles are preferably spherical, and the closer to a true sphere, the better. Examples include: silicone-based light diffusers, acrylic-based light diffusers, silicone rubber elastomers, polymethylsilsesquioxane, acrylic-based, styrene-based, polyester-based, polyolefin-based, urethane-based, nylon-based, styrene-(meth)acrylate-based, fluorine-based, northene-based, silicone-based and other organic diffusers, and silicone-based and acrylic-based light diffusers are preferred as organic particles. As the light diffuser, commercially available products can be used. For example, as a silicone-based light diffuser, "Tospearl (registered trademark) 120S" manufactured by Momentive Performance Materials Japan Co., Ltd. can be used. As an acrylic-based light diffuser, "Ganzpearl (registered trademark) GM-0449S" and "Ganzpearl GM-0205S" manufactured by AICA Industries, Ltd., and "Chemisnow (registered trademark) KMR-3TA" manufactured by Soken Chemical Co., Ltd. can be used.

The light diffuser (C) may preferably be microparticles obtained by copolymerizing styrene monomer, methyl methacrylate monomer, and a crosslinking agent (styrene-methyl methacrylate copolymer crosslinked microparticles). General emulsion polymerization, solution polymerization, dispersion polymerization, suspension polymerization, bulk polymerization, soap-free polymerization, seed polymerization, etc. may be used. Among these polymerization methods, emulsion polymerization, dispersion polymerization, and suspension polymerization are preferred. From the perspective of the physical properties of the light diffuser plate, emulsion polymerization and dispersion polymerization are more preferred.

The crosslinking agent used in the styrene-methyl methacrylate copolymer crosslinked microparticles can be any monomer that contains two or more vinyl or (meth)acrylic groups and can undergo free radical polymerization. Specific examples thereof include divinylbenzene, ethylene glycol diacrylate, ethylene glycol di(methacrylate), trihydroxymethylpropane triacrylate, trihydroxymethylpropane tri(methacrylate), pentaerythritol tetra(acrylate), and pentaerythritol tetra(methacrylate). Moreover, one or more of these crosslinking agents may be used.

The average particle size of the styrene-methyl methacrylate copolymer crosslinked microparticles is 5-30μm. The more preferred average particle size is in the range of 8-20μm. If the average particle size is less than 5μm, the surface state of the obtained light diffusion plate remains smooth, so that the light scattering cannot be fully obtained, resulting in poor light diffusion. If it exceeds 30μm, the surface state of the obtained light diffusion plate is close to smooth, so the light advances and penetrates in a straight line, and the light scattering is reduced, resulting in poor light diffusion and resistance to light source penetration, so it is not preferred. General methods for measuring the average particle size of microparticles include, for example, the Coulter method, dynamic light scattering method, centrifugal sedimentation method, etc.

The refractive index of the styrene-methyl methacrylate copolymer crosslinked microparticles is in the range of 1.54 to 1.57. The more preferred range is 1.55 to 1.57. If the refractive index is less than 1.54, haze may be generated, resulting in reduced light transmittance. If it exceeds 1.57, light diffusion may be reduced. The refractive index can be changed by adjusting the polymerization ratio of each monomer of styrene and methyl methacrylate during the copolymerization of the microparticles.

Styrene-methyl methacrylate copolymer crosslinked microparticles are commercially available, for example, SMX-12R (average particle size 12.3 μm, refractive index 1.56) manufactured by Sekisui Chemicals Co., Ltd., or GMS-6121 (average particle size 11.3 μm, refractive index 1.56) manufactured by Guide Win Special Chemicals Co., Ltd.

The general method for measuring the refractive index of styrene-methyl methacrylate copolymer cross-linked microparticles is, for example, the immersion method. The resin particles are placed on a carrier glass and a refractive liquid (Cargille standard refractive liquid manufactured by CARGILLE) is dripped on. The resin particles and the refractive liquid are thoroughly mixed, and a sodium lamp is irradiated from below. The particle outline is then observed from above. When the outline cannot be seen, the refractive index of the refractive liquid and the resin particles are assumed to be equal. The absolute value of the difference between the refractive index of the light diffuser and the refractive index of the aromatic polycarbonate resin is preferably 0.02 to 0.2. By keeping the refractive index difference within this range, both light diffusion and total light transmittance can be taken into account at a high level. It is more preferable that the refractive index of the light diffuser is lower than the refractive index of the aromatic polycarbonate resin.

The preferred average particle size of the light diffuser is 0.1-50 μm, more preferably 0.5-10 μm, and particularly preferably 1-5 μm. If the average particle size of the light diffuser is too small, sufficient light dispersion effect cannot be obtained, and if it is too large, the surface of the molded product will be rough or the mechanical strength of the molded product will be reduced. Here, the average particle size of the light diffuser is the volume average particle size measured by the Coulter counter method. The Coulter particle size analysis method allows the electrolyte containing suspended sample particles to pass through fine holes (sieve holes) and reads the voltage pulse changes that are proportional to the particle volume to quantify the particle size. By measuring each voltage pulse height one by one, a volume distribution diagram of the sample particles can be obtained. Particle size or particle size distribution measurement using this Coulter particle size analysis method is the most commonly used particle size distribution measurement device.

Furthermore, from the viewpoint of light diffusion, the refractive index difference (Δn) between the light diffuser (C) and the polycarbonate resin (A) is preferably 0.01 or more. In order to fully exert the light diffusion property, for example, to suppress the light source behind the molded body (light diffuser plate, etc.) from penetrating and being seen, and to further exert sufficient brightness, the refractive index difference between the light diffuser and the polycarbonate resin is more preferably 0.05 or more, and particularly preferably 0.07 or more.

Furthermore, the mass average particle size of the light diffuser (C) is usually 0.5 μm or more, preferably 1 μm or more, more preferably 1.5 μm or more, and usually 30 μm or less, preferably 20 μm or less, more preferably 10 μm or less, particularly preferably 5 μm or less, and even more preferably 3 μm or less. If the mass average particle size is too small, the light diffusion property of the obtained polycarbonate resin composition is poor, and when used as a diffusion plate, the light source may be seen through or the visibility may be poor; on the contrary, if it is too large, the diffusion effect may be reduced relative to the content.

The light diffuser (C) may be used alone or in combination of two or more in any combination and ratio. It is preferred to use a polysilicone light diffuser in combination with other light diffusers.

It is also possible to use any one of a polysilicone light diffuser, an acrylic light diffuser, and styrene-methyl methacrylate copolymer crosslinked microparticles and an inorganic light diffuser (inorganic microparticles) in combination. When any one of a polysilicone light diffuser, an acrylic light diffuser, and styrene-methyl methacrylate copolymer crosslinked microparticles and an inorganic light diffuser are used in combination, the same light diffusion property as before the reduction can be obtained while reducing the amount of the polysilicone or organic diffuser blended. The inorganic light diffuser used in combination is preferably titanium oxide (white pigment). As titanium oxide, for example, TIPAQUE (registered trademark) PC-3 manufactured by Ishihara Sangyo Co., Ltd., CP-K manufactured by Resino Color Industries, Ltd., KRONOS (registered trademark) 2233 manufactured by Kronos Corporation, etc. can be used.

The amount of the light diffuser (C) blended is preferably 0.1 to 6.0 parts by weight, more preferably 1.0 to 5.0 parts by weight, relative to 100 parts by weight of the linear aromatic polycarbonate resin (A). If it is less than 0.1 parts by weight, light is not sufficiently scattered and the effect of preventing light source visibility is poor; if it exceeds 6.0 parts by weight, there is a risk that the transmittance is significantly reduced.

The aromatic polycarbonate resin composition of the embodiment of the present invention may contain a phosphorus antioxidant (D) as needed. When the aromatic polycarbonate resin composition contains the polyether derivative (B), the diffuser (C) and the phosphorus antioxidant (D) at the same time, the excellent optical properties required for the light diffusing molded product can be maintained and improved, and in particular, the initial optical properties of the molded product composed of the obtained aromatic polycarbonate resin composition will not be deteriorated, and the deterioration caused by the use conditions can be prevented.

The phosphorus-based antioxidant (D) is not particularly limited as long as the aromatic polycarbonate resin composition of the present invention can be obtained. It is preferably a phosphite compound having the following phosphite structure. [Chemistry 3]

In the aromatic polycarbonate resin composition of the embodiment of the present invention, the above-mentioned phosphorus-based antioxidant (D) preferably contains at least one compound selected from: a phosphite compound represented by the following formula (12), a phosphite compound represented by the following formula (13), a phosphite compound represented by the following formula (14), and a phosphite compound represented by the following formula (15).

The phosphorus-based antioxidant (D) preferably contains, for example, a compound represented by the following formula (12).

Formula (12): [Chemical 4] (In the formula, ^R1 represents an alkyl group with 1 to 20 carbon atoms, and a represents an integer from 0 to 3)

In the above formula (12), ^R1 is an alkyl group having 1 to 20 carbon atoms, and preferably an alkyl group having 1 to 10 carbon atoms.

Examples of the compound represented by formula (12) include triphenyl phosphite, tricresyl phosphite, 2,4-di-tert-butylphenyl phosphate, 2,4-di-tert-butylphenyl phosphate, and 2,4-di-tert-butylphenyl phosphate. Among them, 2,4-di-tert-butylphenyl phosphate is particularly preferred, and is commercially available, for example, as IRGAFOS 168 manufactured by BASF ("IRGAFOS" is a registered trademark of BASF SOCIETAS EUROPAEA).

The phosphorus-based antioxidant (D) preferably contains, for example, a compound represented by the following formula (13).

Formula (13): [Chemical 5] (In the formula, R ² , R ³ , R ⁵ and R ⁶ each independently represent a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, an alkylcycloalkyl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, or a phenyl group. R ⁴ represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. X represents a single bond, a sulfur atom, or a group represented by the formula: -CHR ⁷ - (wherein R ⁷ represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or a cycloalkyl group having 5 to 8 carbon atoms). A represents an alkylene group having 1 to 8 carbon atoms, or the formula: *-COR ⁸ - (wherein R ⁸ represents a single bond or an alkylene group having 1 to 8 carbon atoms, and * represents a bond group on the oxygen side). Y and Z represent that one of them is a hydroxyl group, an alkoxy group having 1 to 8 carbon atoms, or an aralkyloxy group having 7 to 12 carbon atoms, and the other is a hydrogen atom or an alkyl group having 1 to 8 carbon atoms.

In formula (13), R ² , R ³ , R ⁵ and R ⁶ each independently represent a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, an alkylcycloalkyl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, or a phenyl group.

Examples of the alkyl group having 1 to 8 carbon atoms include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, t-butyl, t-pentyl, iso-octyl, t-octyl, 2-ethylhexyl, etc. Examples of the cycloalkyl group having 5 to 8 carbon atoms include cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, etc. Examples of the alkylcycloalkyl group having 6 to 12 carbon atoms include 1-methylcyclopentyl, 1-methylcyclohexyl, 1-methyl-4-isopropylcyclohexyl, etc. Examples of the aralkyl group having 7 to 12 carbon atoms include benzyl, α-methylbenzyl, α,α-dimethylbenzyl, etc.

The above ^R2 , ^R3 and ^R5 are independently an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, or an alkylcycloalkyl group having 6 to 12 carbon atoms. Particularly preferably ^{, R2} and ^R5 are independently a tertiary alkyl group such as tertiary butyl, tertiary pentyl, tertiary octyl, or a cyclohexyl or 1-methylcyclohexyl group. Particularly preferably, ^R3 is an alkyl group having 1 to 5 carbon atoms such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tertiary butyl, tertiary pentyl, or the like, and more preferably, a methyl group, a tertiary butyl, or a tertiary pentyl.

The above ^R6 is preferably a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or a cycloalkyl group having 5 to 8 carbon atoms, and more preferably a hydrogen atom, a methyl group, an ethyl group, a n-propyl group, an isopropyl group, a n-butyl group, an isobutyl group, a sec-butyl group, a t-butyl group, a t-pentyl group or an alkyl group having 1 to 5 carbon atoms.

In formula (13), ^R4 represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. Examples of the alkyl group having 1 to 8 carbon atoms include the alkyl groups exemplified in the above description of ^R2 , ^R3 , ^R5 and ^R6 . ^R4 is particularly preferably a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and more preferably a hydrogen atom or a methyl group.

In formula (13), X represents a single bond, a sulfur atom, or a group represented by the formula: -CHR ⁷ -. In the formula: -CHR ⁷ -, R ⁷ represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or a cycloalkyl group having 5 to 8 carbon atoms. Examples of the alkyl group having 1 to 8 carbon atoms and the cycloalkyl group having 5 to 8 carbon atoms include the alkyl groups and cycloalkyl groups exemplified in the above description of R ² , R ³ , R ⁵ , and R ⁶ . X is particularly preferably a single bond, a methylene group, or a methylene group substituted by a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, or the like, and is more preferably a single bond.

In formula (13), A represents an alkylene group having 1 to 8 carbon atoms, or a group represented by the formula: *-COR ⁸ -. Examples of the alkylene group having 1 to 8 carbon atoms include methylene, ethylene, propylene, butylene, pentamethylene, hexamethylene, octamethylene, 2,2-dimethyl-1,3-propylene, etc., preferably propylene. In the formula: *-COR ⁸ -, R ⁸ represents a single bond, or an alkylene group having 1 to 8 carbon atoms. Examples of the alkylene group having 1 to 8 carbon atoms representing R ⁸ include the alkylene groups exemplified in the above description of A. R ⁸ is preferably a single bond or an ethylene group. In the formula: *-COR ⁸ -, * represents a bonding group on the oxygen atom side, indicating that the carbonyl group is bonded to the oxygen atom of the phosphate group.

In formula (13), Y and Z represent that one of them is a hydroxyl group, an alkoxy group having 1 to 8 carbon atoms, or an aralkyloxy group having 7 to 12 carbon atoms, and the other is a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. Examples of the alkoxy group having 1 to 8 carbon atoms include methoxy, ethoxy, propoxy, tert-butoxy, and pentyloxy. Examples of the aralkyloxy group having 7 to 12 carbon atoms include benzyloxy, α-methylbenzyloxy, and α,α-dimethylbenzyloxy. Examples of the alkyl group having 1 to 8 carbon atoms include the alkyl groups exemplified in the above description of R ² , R ³ , R ⁵ , and R ⁶ .

The compound represented by formula (13) may be exemplified by: 2,4,8,10-tetra-tert-butyl-6-[3-(3-methyl-4-hydroxy-5-tert-butylphenyl)propoxy]dibenzo[d,f][1,3,2]diphosphophtholhydrazine, 6-[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propoxy]-2,4,8,10-tetra-tert-butyldibenzo[d,f][1,3,2]diphosphophtholhydrazine 、6-[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propoxy]-4,8-di-tert-butyl-2,10-dimethyl-12H-dibenzo[d,g][1,3,2]dioxophosphine、6-[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propoxy]-4,8-di-tert-butyl-2,10-dimethyl-12H-dibenzo[d,g][1,3,2]dioxophosphine Among them, when the obtained aromatic polycarbonate resin composition is used in a field requiring optical properties, 2,4,8,10-tetra-tert-butyl-6-[3-(3-methyl-4-hydroxy-5-tert-butylphenyl)propoxy]dibenzo[d,f][1,3,2]dioxaphosphocin is preferred, and it can be commercially obtained, for example, as SUMIRAIZER GP manufactured by Sumitomo Chemical Co., Ltd. ("SUMIRAIZER" is a registered trademark).

The phosphorus-based antioxidant (D) preferably contains, for example, a compound represented by the following formula (14).

Formula (14): [Chemical 6] (In the formula, ^R9 and ^R10 are independently an alkyl group having 1 to 20 carbon atoms, or an aryl group which may be substituted by an alkyl group; b and c are independently integers of 0 to 3.)

Examples of the compound represented by formula (14) include bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphate and phenylbisphenol A pentaerythritol diphosphate. Bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphate is commercially available under the trade name "ADKSTAB PEP-24G" manufactured by ADEKA. ADKSTAB PEP-36 ("ADKSTAB" is a registered trademark) manufactured by ADEKA is also commercially available.

The phosphorus-based antioxidant (D) preferably contains, for example, a compound represented by the following formula (15).

Formula (15): [Chemical 7]

(In the formula, R ¹¹ to R ¹⁸ represent independently an alkyl group or alkenyl group having 1 to 3 carbon atoms. R ¹¹ and R ¹² , R ¹³ and R ¹⁴ , R ¹⁵ and R ¹⁶ , and R ¹⁷ and R ¹⁸ may be bonded to each other to form a ring. R ¹⁹ to R ²² represent independently a hydrogen atom or an alkyl group having 1 to 20 carbon atoms. d to g represent independently an integer of 0 to 5. X ¹ to X ⁴ represent independently a single bond or a carbon atom. When X ¹ to X ⁴ are single bonds, the functional groups in R ¹¹ to R ²² connected to the single bonds are excluded from the general formula (15).)

Specific examples of the compound represented by formula (15) include bis(2,4-diisopropylphenyl)pentaerythritol diphosphate. It is commercially available under the trade name "Doverphos (registered trademark) S-9228" manufactured by Dover Chemical Co., Ltd. and the trade name "ADKSTAB PEP-45" (bis(2,4-diisopropylphenyl)pentaerythritol diphosphate) manufactured by ADEKA Corporation.

The aromatic polycarbonate resin composition preferably satisfies at least one of the following items: The phosphite compound represented by the formula (12) contains tris(2,4-di-tert-butylphenyl) phosphate; The phosphite compound represented by the formula (13) contains 2,4,8,10-tetra-tert-butyl-6-[3-(3-methyl-4-hydroxy-5-tert-butylphenyl) propoxy] dibenzo[d,f][1,3,2]diphosphophenanthene; The phosphite compound represented by the formula (14) contains 3,9-bis(2,6-di-tert-butyl-4-methylphenoxy)-2,4,8,10-tetra-tert-butyl-3,9-diphosphaspiro[5,5]undecane; and The phosphite compound represented by the formula (15) contains bis(2,4-diisopropylphenyl)pentaerythritol diphosphate.

The amount of the phosphorus-based antioxidant (D) is preferably 0.5 parts by weight or less, more preferably 0.02 to 0.2 parts by weight, relative to 100 parts by weight of the aromatic polycarbonate resin (A).

The aromatic polycarbonate resin composition of the embodiment of the present invention preferably contains a polyether derivative (B), a light diffuser (C), a phosphorus antioxidant (D), and an aromatic compound (E) represented by the following formula (1). By using the polyether derivative (B), the light diffuser (C), the phosphorus antioxidant (D), and the aromatic compound (E), the excellent optical properties required for the light diffusing molded article can be maintained, and the molded article composed of the obtained aromatic polycarbonate resin composition can be prevented from being deteriorated due to use conditions and aging.

For example, it can effectively prevent optical molded products formed from aromatic polycarbonate resin compositions from thermal degradation (cloudiness or coloration) caused by long-term exposure to light from light sources (LED light sources, etc.). If light-diffusing molded products are exposed to light under adverse conditions such as hot weather and/or for a long period of time, the surface temperature of the molded products rises, and the linear aromatic polycarbonate resin (A) contained in the aromatic polycarbonate resin composition may gradually undergo thermal degradation in small amounts. In addition, the polyether derivative (B) in the resin composition may be modified, which may impair the transparency (brightness or light transmittance) expected of the aromatic polycarbonate resin composition used in light-diffusing molded products, resulting in cloudiness or coloration (light to dark coloration) on the surface of the molded products.

The inventors of this case have conducted in-depth research on this topic and found that as a compound that can inhibit the modification and degradation of polyether derivatives (B), the specific aromatic compound (E) of the following formula (1) is particularly effective. By adding the specific aromatic compound (E) to the polyether derivative (B) in advance, or adding it before melt kneading to obtain an aromatic polycarbonate resin composition, the degradation of the polyether derivative (B) in the molded product can be inhibited, and the whitening or coloring (light to dark coloring) phenomenon can be reduced or alleviated. Formula (1): [Chemical 8]

The amount of the aromatic compound (E) used in the embodiment of the present invention is preferably 0.003 parts by weight or less relative to 100 parts by weight of the aromatic polycarbonate resin (A). In order to obtain the effect of inhibiting the modification of the polyether derivative (B) caused by the aromatic compound (E), the amount of the aromatic compound (E) is set to 0.0001 parts by weight or more relative to 100 parts by weight of the aromatic polycarbonate resin (A). The amount of the aromatic compound (E) is more preferably 0.0005 parts by weight or more and 0.003 parts by weight or less relative to 100 parts by weight of the aromatic polycarbonate resin (A). If the amount of the aromatic compound (C) is less than 0.0001 parts by weight, the effect of inhibiting whitening or coloring is insufficient. On the other hand, if the amount of the aromatic compound (C) exceeds 0.003 parts by weight, the high level of light transmittance and hue required for the optically formed body may not be achieved, so it is best to avoid this.

In addition to the above components, the aromatic polycarbonate resin composition of the embodiment is used in conjunction with the molded product obtained by molding the aromatic polycarbonate resin composition, and can appropriately use, for example, an ultraviolet absorber that is a component that can further improve the weather resistance of the obtained aromatic polycarbonate resin composition.

Examples of the ultraviolet absorber include benzotriazole compounds, trioxane compounds, diphenyl ketone compounds, oxalic acid anilide compounds, and other ultraviolet absorbers that are usually blended into polycarbonate resins. These may be used alone or in combination of two or more.

Examples of benzotriazole compounds include 2-(2-hydroxy-5-tert-octylphenyl)benzotriazole, 2-(3-tert-butyl-2-hydroxy-5-methylphenyl)-5-chloro-2H-benzotriazole, 2-(3,5-di-tert-pentyl-2-hydroxyphenyl)-2H-benzotriazole, 2-(2H-benzotriazol-2-yl)-4-methyl-6-(3,4,5,6-tetrahydrophthalimide 2-(2-Hydroxy-5-tert-octylphenyl)benzotriazole, 2-[2'-hydroxy-3,5-bis(1,1-dimethylbenzyl)phenyl]-2H-benzotriazole, 2,2'-methylenebis[6-(2H-benzotriazol-2-yl)4-(1,1,3,3-tetramethylbutyl)phenol], etc. Among them, 2-(2-hydroxy-5-tert-octylphenyl)benzotriazole is particularly preferred, and commercially available products include TINUVIN 329 manufactured by BASF (TINUVIN is a registered trademark), SEESORB 709 manufactured by SHIPRO Chemicals, and KEMISORB 79 manufactured by CHEMIPRO Chemicals.

Examples of trioxane compounds include 2,4-diphenyl-6-(2-hydroxyphenyl-4-hexyloxyphenyl)-1,3,5-trioxane, 2-[4,6-bis(2,4-dimethylphenyl)-1,3,5-trioxane-2-yl]-5-(octyloxy)phenol, and 2-(4,6-diphenyl-1,3,5-trioxane-2-yl)-5-[(hexyl)oxy]phenol. Commercially available products include TINUVIN 1577 manufactured by BASF.

Anilide oxalate compounds are commercially available, for example, as Sanduvor VSU manufactured by Clariant Japan.

Examples of the phenyl ketone compounds include 2,4-dihydroxyphenyl ketone and 2-hydroxy-4-n-octyloxyphenyl ketone.

The amount of the ultraviolet absorber is 0-1.0 part by weight, preferably 0-0.5 part by weight, relative to 100 parts by weight of the aromatic polycarbonate resin (A). When the amount of the ultraviolet absorber exceeds 1.0 part by weight, there is a possibility that the initial hue of the aromatic polycarbonate resin composition is reduced. Moreover, when the amount of the ultraviolet absorber reaches 0.1 part by weight or more, the effect of further improving the weather resistance of the aromatic polycarbonate resin composition can be greatly exerted.

The aromatic polycarbonate resin composition of the embodiment of the present invention may contain an epoxy compound (F). When the aromatic polycarbonate resin composition contains the polyether derivative (B), the aromatic compound (E) and the epoxy compound (F) at the same time, the excellent optical properties required for the light diffusing molded product can be maintained and improved, and the initial optical properties of the molded product composed of the obtained aromatic polycarbonate resin composition will not be deteriorated, and degradation caused by use conditions and aging can be prevented.

The epoxy compound (F) has at least one epoxy group in the molecule, and is not particularly limited as long as the aromatic polycarbonate resin composition of the present invention can be obtained. The epoxy compound (F) may include, for example, 3',4'-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, epoxidized soybean oil, ε-caprolactone-modified 3',4'-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, epoxy-containing acrylic acid-styrene polymer, 2,2-bis(4-hydroxycyclohexyl)propane-diethoxypropyl ether, etc. The epoxy compound (F) preferably contains 3',4'-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate.

In the aromatic polycarbonate resin composition of the embodiment of the present invention, the epoxy compound (F) is preferably contained in an amount of 0.001 to 0.2 parts by weight, more preferably 0.002 to 0.1 parts by weight, and particularly preferably 0.005 to 0.05 parts by weight, relative to 100 parts by weight of the linear aromatic polycarbonate resin. In the aromatic polycarbonate resin composition of the embodiment of the present invention, when the epoxy compound (E) is contained in an amount of 0.001 to 0.2 parts by weight relative to 100 parts by weight of the linear aromatic polycarbonate resin, the initial optical properties (integrated transmittance and yellowness) of the molded article formed from the obtained aromatic polycarbonate resin composition can be improved while maintaining the excellent optical properties required for the light diffusing molded article, and degradation due to use and aging can be prevented.

Furthermore, the aromatic polycarbonate resin composition of the embodiment may also be appropriately blended with various additives such as heat stabilizers, other antioxidants, colorants, release agents, softeners, antistatic agents, impact modifiers, and polymers other than linear aromatic polycarbonate resins, within the scope of not impairing the effects of the present invention.

The method for producing the aromatic polycarbonate resin composition of the embodiment of the present invention can be exemplified by: mixing a linear aromatic polycarbonate resin, a polyether derivative (B) and a light diffuser (C), and optionally further mixing in a phosphorus antioxidant (D), an aromatic compound (E), an epoxy compound (F), the above-mentioned various additives, and a polymer other than the linear aromatic polycarbonate resin. As long as the aromatic polycarbonate resin composition of the present invention can be obtained, the production method is not particularly limited, and the type and amount of each component can be appropriately adjusted. The mixing method of the components is also not particularly limited, and examples thereof include: a method of mixing using a known mixer such as a rotary drum and a belt blender; and a method of melt kneading using an extruder. By these methods, the particles of the aromatic polycarbonate resin composition can be easily obtained. The aromatic compound (E) can be mixed before melt kneading, or can be added or mixed in the polyether derivative (B) in advance.

The shape and size of the particles of the aromatic polycarbonate resin composition obtained as described above are not particularly limited, as long as they are the shape and size of general resin particles. For example, the particle shape can be set to be elliptical, cylindrical, etc. The size of the particles is preferably set to a length of about 2 to 8 mm. In the case of an elliptical column, the long diameter of the cross-sectional ellipse is preferably about 2 to 8 mm and the short diameter is about 1 to 4 mm. In the case of a cylindrical shape, the diameter of the cross-sectional circle is preferably about 1 to 6 mm. In addition, the obtained particles can be each of such a size, all particles forming a particle aggregate can be of such a size, or the average value of the particle aggregate can be of such a size, and there is no special limitation.

The light diffusing molded product of the embodiment of the present invention can be obtained by molding the above-mentioned aromatic polycarbonate resin composition. As a large and thin-walled light diffusing plate (especially a light diffusing plate for an image display device), a light diffusing plate with a surface area of 500 to 50,000 cm ² can be obtained. The surface area of the light diffusing plate is preferably 1,000 to 25,000 cm ² and the thickness is preferably 0.3 to 3 mm. Thus, according to the aromatic polycarbonate resin composition of the present invention, a large, thin-walled (lightweight) light diffusing plate with high dimensional stability can be manufactured.

The method for producing the light diffusing molded article is not particularly limited as long as the light diffusing molded article of the present invention can be obtained. For example, the method of molding the aromatic polycarbonate resin composition by a known injection molding method, compression molding method, etc. can be used.

The light diffusing molded product of the present invention can be exemplified by light diffusing plates, light diffusing films, electronic and electrical equipment, OA machine parts, vehicle parts, machine parts, agricultural materials, fishing materials, transport containers, packaging containers, sundries, etc. More specifically, it is preferably a light diffusing plate for an image display device (a light diffusing plate used in a backlight module of a liquid crystal display device, etc., a light diffusing plate used in a screen of a projection type display device such as a projection television, etc.). The backlight module of a liquid crystal display device, etc. can use various light sources (cold cathode tubes, LEDs, etc.).

As described above, the exemplary embodiments of the present invention have been described. However, the technology of the present invention is not limited thereto, and embodiments that are appropriately modified, replaced, added, omitted, etc. are also applicable. [Example]

The present invention is described in more detail below using examples, but the present invention is not limited to these examples. In addition, unless otherwise stated, "parts" and "%" are weight-based.

The following materials were used as raw materials. 1. Linear aromatic polycarbonate resin: Polycarbonate resin synthesized from bisphenol A and carbonyl chloride Viscosity average molecular weight: 15,000, SD POLYCA 200-80 (trade name) manufactured by Sumika Polycarbonate Co., Ltd., "SD POLYCA" is a registered trademark of Sumika Polycarbonate Co., Ltd., hereinafter also referred to as "(A1)".

2. Polyether derivative (B): 2-1. Modified diol composed of butanediol units and propylene glycol units (random copolymerization) Weight average molecular weight: 2000, pH: 6.7 (JIS K1557-5), POLYCERIN DCB-2000 (trade name) manufactured by NOF Corporation, hereinafter also referred to as "(B1)".

2-2. Modified diol composed of ethylene glycol units and propylene glycol units (random copolymerization) Weight average molecular weight: 1750, UNILUB 50DE-25 (trade name) manufactured by NOF Corporation, hereinafter also referred to as "(B2)".

2-3. Polybutylene glycol Weight average molecular weight: 1000, PTG-1000SN (trade name) manufactured by Hodogaya Chemical Industry Co., Ltd., hereinafter also referred to as "(B3)".

3. Light diffuser (C): 3-1. Polymethylsilsesquioxane diffuser Tospearl 120S (trade name) manufactured by Momentive, hereinafter referred to as "(C1)". 3-2. Acrylic diffuser GM-0449S (trade name) manufactured by AICA Industries, hereinafter referred to as "(C2)". 3-3. Styrene-methyl methacrylate copolymer crosslinked microparticles SMX-12R (trade name) manufactured by Sekisui Chemicals, hereinafter referred to as "(C3)". 3-4. Inorganic diffuser (titanium oxide) TIPAQUE (registered trademark) PC-3 (trade name) manufactured by Ishihara Sangyo Co., Ltd., hereinafter referred to as "(C4)".

4. Phosphorus antioxidant (D): 4-1. Phosphorus (2,4-di-tert-butylphenyl ester) represented by the following formula: IRGAFOS 168 (trade name) manufactured by BASF, hereinafter also referred to as "(D1)".

4-2. 2,4,8,10-tetra-tert-butyl-6-[3-(3-methyl-4-hydroxy-5-tert-butylphenyl)propoxy]dibenzo[d,f][1,3,2]diphosphinothionine [Chemical 10] represented by the following formula SUMIRAIZER GP (trade name) manufactured by Sumitomo Chemical Co., Ltd., hereinafter also referred to as "(D2)".

4-3. Bis(2,4-diisopropylphenyl)pentaerythritol diphosphate (IUPAC name: 3,9-bis[2,4-bis(α,α-dimethylbenzyl)phenoxy]-2,4,8,10-tetrakis-3,9-diphosphaspiro[5.5]undecane) represented by the following formula: Doverphos S-9228 (trade name) manufactured by Dover Chemical Co., Ltd., hereinafter also referred to as "(D3)".

4-4. Bis(2,6-di-tert-butyl-4-methylphenyl)pentaerythritol diphosphate (IUPAC name: 3,9-bis(2,6-di-tert-butyl-4-methylphenoxy)-2,4,8,10-tetrakis-3,9-diphosphaspiro[5,5]undecane) represented by the following formula: ADKSTAB PEP-36 (trade name) manufactured by ADEKA, hereinafter also referred to as "(D4)". 5. Aromatic compound (E): 3,5-di-tert-butyl-4-hydroxytoluene manufactured by Wako Pure Chemical Industries, Ltd., hereinafter also referred to as "(E1)".

6. Epoxy compound (F) 3',4'-Epoxycyclohexylmethyl-3,4-epoxycyclohexylcarboxylate Celloxide 2021P (trade name) manufactured by Daicel Chemical Industries, Ltd., hereinafter also referred to as "(F1)".

(Examples 1 to 14 and Comparative Examples 1 and 2) The above raw materials were put into a drum in the proportions shown in Table 1, and after dry mixing for 10 minutes, a double-screw extruder (TEX30α, manufactured by Nippon Steel Works, Ltd.) was used to perform melt kneading at a melting temperature of 230°C to obtain aromatic polycarbonate resin composition particles of Examples 1 to 11 and Comparative Examples 1 and 2, respectively. In addition, the particles obtained in the Examples and Comparative Examples are roughly elliptical columns, and the average length of the aggregate composed of 100 particles is about 5.1 mm to about 5.4 mm, the average major diameter of the cross-sectional ellipse is about 4.1 mm to about 4.3 mm, and the average minor diameter is about 2.2 mm to about 2.3 mm.

The obtained granules were used to prepare test pieces for each evaluation according to the following method and provided for evaluation. The results are shown in Table 1.

(Test piece preparation method) The obtained pellets were dried at 120℃ for more than 4 hours, and then used an injection molding machine (manufactured by FANUC, ROBOSHOT S2000i100A) to form a three-layer plate-shaped test piece with a width of 50mm and a length of 90mm (3mm thick part: 35mm long / 2mm thick part: 30mm long / 1mm thick part: 25mm long) at a molding temperature of 290℃ and a mold temperature of 80℃.

(Test piece evaluation method) 1. Total light transmittance (%): The total light transmittance is measured according to JIS K7361 using the 1mm portion of the obtained three-layer plate-shaped test piece. The larger the value, the better the light transmittance of the molded product. The total light transmittance value of the molded product with a thickness of 1mm is rated as "○" if it reaches 40% or more, and the rest is rated as "×".

2. Light diffusion (degrees): Use the 1mm portion of the three-layer plate test piece used in 1 above to obtain the light diffusion (D50) using an automatic goniophotometer (goniophotometer GP-1R manufactured by Murakami Color Technology Laboratory). The detailed measurement method is as follows. The larger the value, the better the light diffusion of the molded product. Let the straight light emitted by the light source of the automatic goniophotometer irradiate the normal direction of the test piece, and use the movable light receiver to measure the intensity of the transmitted light. For the angle deviating from the normal direction, the transmittance is plotted, and the angle (D50) at which the transmittance is 50% of the straight transmittance is obtained. The unit is "degree", and the light diffusion (D50) of 30 degrees or more is rated as good.

3. Anti-light source transparency (visual judgment): A 3cm×5cm rectangular hole was chiseled in the center of a 20W straight tube LED lamp made by Philips, and a 3cm×5cm×1mm injection molded plate was set at a height of about 1.5cm from the LED light source. The anti-light source transparency was visually judged from a height of about 20cm on the injection molded plate where the LED lamp was set. When the light diffusion is very good and the outline of the LED light source disappears, it is rated as excellent "◎". When the outline of the LED light source can be slightly distinguished, it is rated as good "○", and when the light diffusion is lacking and the outline of the LED light source is clearly distinguished, it is rated as poor "×".

4. Yellow chromaticity: Using the 1mm portion of the obtained three-layer plate test piece, a spectrophotometer (UH4150 manufactured by Hitachi Ltd.) was used to obtain the yellow chromaticity (hereinafter referred to as "YI") of each test piece before and after the heating test using a standard light source D65 at a 10-degree field of view. The heating test was carried out by placing the above test piece in an inert furnace IPHH-201M manufactured by ESPEC and maintaining it at 90°C for 500 hours. In addition, YI below 4.0 was rated as good "◎", above 4.0 and below 5.0 was rated as usable "○", and above 5.0 was rated as poor "×".

Tables 1 to 3 show the raw materials, blending ratios, and evaluation results of each embodiment and comparative example. [Table 1] Embodiment 1 2 3 4 5 6 Polycarbonate resin A1 200-80 100 100 100 100 100 100 Polyether derivatives B1 POLYCERIN DCB-2000 1.0 0.5 1.0 1.0 1.0 1.0 B2 UNILUBE 50DE-25 B3 PTG-1000 Light Diffuser C1 SL-200M 3.0 3.0 1.0 5.0 3.0 3.0 C2 GM-0449S 1.0 C3 SMX-12R 2.0 C4 TIPAQUE PC-3 Phosphite compounds D1 Irgafos P-168 0.05 0.05 0.05 0.05 0.05 0.05 D2 Sumilizer GP D3 Doverfos S-9228PC D4 ADKSTAB PEP-36 Phenolic compounds E1 BHT (added during granulation) 0.002 0.002 0.002 Epoxides F1 Celloxide 2021P 0.02 0.02 0.02 Before the test Total light transmittance 53.4 52.6 63.4 47.3 52.1 50.7 ○ ○ ○ ○ ○ ○ Light Diffusion 59.5 59.5 52.7 59.6 59.5 59.6 ○ ○ ○ ○ ○ ○ Light source transparency 99.71 99.73 99.65 99.71 99.74 99.75 ◎ ◎ ○ ◎ ◎ ◎ Yellow chromaticity YI 1.8 2.0 2.0 3.5 2.2 2.2 ◎ ◎ ◎ ◎ ◎ ◎ After heating test (90℃×500hr) Yellow chromaticity YI 2.1 2.3 2.1 3.7 2.5 2.5 ◎ ◎ ◎ ◎ ◎ ◎ [Table 2] Embodiment 7 8 9 10 11 Polycarbonate resin A1 200-80 100 100 100 100 100 Polyether derivatives B1 POLYCERIN DCB-2000 1.0 1.0 1.0 B2 UNILUBE 50DE-25 1.0 B3 PTG-1000 1.0 Light Diffuser C1 SL-200M 3.0 3.0 3.0 3.0 3.0 C2 GM-0449S C3 SMX-12R C4 TIPAQUE PC-3 Phosphite compounds D1 Irgafos P-168 D2 Sumilizer GP 0.05 D3 Doverfos S-9228PC 0.05 0.05 D4 ADKSTAB PEP-36 0.05 0.05 Phenolic compounds E1 BHT (added during granulation) 0.002 0.002 Epoxides F1 Celloxide 2021P 0.02 0.02 Before the test Total light transmittance 52.7 53.4 53.4 53.4 53.3 ○ ○ ○ ○ ○ Light Diffusion 59.5 59.5 59.5 59.5 59.5 ○ ○ ○ ○ ○ Light source transparency 99.72 99.72 99.72 99.72 99.72 ◎ ◎ ◎ ◎ ◎ Yellow chromaticity YI 2.3 1.9 1.8 2.0 1.9 ◎ ◎ ◎ ◎ ◎ After heating test (90℃×500hr) Yellow chromaticity YI 3 2.2 2.3 2.2 2.1 ◎ ◎ ◎ ◎ ◎ [table 3] Embodiment Comparison Example 12 13 14 1 2 Polycarbonate resin A1 200-80 100 100 100 100 100 Polyether derivatives B1 POLYCERIN DCB-2000 1.0 1.0 1.0 B2 UNILUBE 50DE-25 1.0 B3 PTG-1000 1.0 Light Diffuser C1 SL-200M 0.5 0.3 0.05 7.0 C2 GM-0449S 1.0 C3 SMX-12R C4 TIPAQUE PC-3 0.05 Phosphite compounds D1 Irgafos P-168 0.05 0.05 0.05 0.05 D2 Sumilizer GP D3 Doverfos S-9228PC D4 ADKSTAB PEP-36 0.05 Phenolic compounds E1 BHT (added during granulation) 0.002 Epoxides F1 Celloxide 2021P 0.02 0.02 Before the test Total light transmittance 70.8 85.3 47.7 85.2 37.5 ○ ○ ○ ○ × Light Diffusion 36.7 twenty one 58.5 16.7 59.9 ○ ○ ○ × ○ Light source transparency 99.53 98.31 99.66 47.3 99.8 ○ ○ ○ × ◎ Yellow chromaticity YI 2.4 1.8 4.7 3.7 4.3 ◎ ◎ ○ ◎ ○ After heating test (90℃×500hr) Yellow chromaticity YI 2.6 2 4.9 4 4.7 ◎ ◎ ○ ◎ ○

The aromatic polycarbonate resin compositions of Examples 1 to 14 contain linear aromatic polycarbonate resin, polyether derivative (B) and light diffuser (C) in specific proportions, and optionally phosphorus antioxidant (D), aromatic compound (E) and epoxy compound (F), etc. Therefore, the test pieces formed from the aromatic polycarbonate resin composition have high total light transmittance, light diffusion, and light source resistance, low yellowness, and almost no deterioration after heating test.

Furthermore, the molded product formed by molding the aromatic polycarbonate resin composition has low yellowness and excellent hue, and also has almost no deterioration after a heating test.

In contrast, the aromatic polycarbonate resin composition of Comparative Example 1 has a low light diffusion rate and poor light source resistance because the amount of light diffuser blended is relatively small. In addition, the aromatic polycarbonate resin composition of Comparative Example 2 has a low total light transmittance because the amount of light diffuser blended is relatively large.

As described above, the exemplary embodiments of the present invention are described. Therefore, a detailed description is given.

Therefore, the constituent elements described in the detailed description include not only the essential constituent elements that are useful for solving the problem, but also the essential constituent elements that are not essential for solving the problem in order to illustrate the above technology. Therefore, although the detailed description is given for these non-essential constituent elements, these non-essential constituent elements should not be considered as essential elements.

Furthermore, the above-mentioned implementation forms are only examples of the present invention technology. Various changes, substitutions, additions, omissions, etc. can be implemented within the scope of the patent application or its equivalent scope. (Industrial applicability)

The aromatic polycarbonate resin composition of the present invention does not impair the heat resistance, mechanical strength and other properties inherent in the polycarbonate resin, and has excellent thermal stability and weather resistance. Moreover, even when the molded product containing the aromatic polycarbonate resin composition of the present invention is heated, the appearance and optical properties are still excellent. Therefore, even when the diffuser surface of a thin diffuser light source of about 0.3 mm in thickness is irradiated for a long time and is continuously heated, the color of the diffuser does not change and the appearance and optical properties do not decrease, and the industrial utilization value is extremely high.

Claims (6)

An aromatic polycarbonate resin composition comprises: a linear aromatic polycarbonate resin (A), a polyether derivative (B), a light diffuser (C), a phosphorus antioxidant (D), and an aromatic compound (E) represented by the following formula (1); wherein, relative to 100 parts by weight of the linear aromatic polycarbonate resin (A), the polyether derivative (B) is contained in an amount of 0.1 to 2.0 parts by weight, the light diffuser (C) is contained in an amount of 0.1 to 6.0 parts by weight, the phosphorus antioxidant (D) is contained in an amount of up to 0.5 parts by weight, and the aromatic compound (E) is contained in an amount of up to 0.003 parts by weight; Formula (1): [Chemical 1] . The aromatic polycarbonate resin composition of claim 1, wherein the polyether derivative (B) contains a polyether derivative represented by the following formula (2) and having a weight average molecular weight of 500 to 8000; Formula (2): RO-(X-O)m(Y-O)n-R' (wherein, R and R' are each independently a hydrogen atom or an alkyl group having 1 to 30 carbon atoms; X is a linear or branched alkyl group having 2 to 4 carbon atoms; Y is a linear or branched alkyl group having 2 to 5 carbon atoms; X and Y may be the same or different, m and n are each independently 3 to 60, and m+n is 6 to 120). The aromatic polycarbonate resin composition of claim 1, wherein the light diffuser (C) is a silicone-based light diffuser, an acrylic-based light diffuser, and inorganic microparticles, or a combination thereof. The aromatic polycarbonate resin composition of claim 1 further comprises at least one selected from the group consisting of a thermal stabilizer, a colorant, a release agent, a softener, an antistatic agent, and an impact modifier. A light diffusing molded article comprises the aromatic polycarbonate resin composition of any one of claims 1 to 4. A light diffusing molded article as claimed in claim 5, wherein the light diffusing molded article is a light diffusing plate or a light diffusing film for an image display device.