JP7845899B2 - Polycarbonate resin composition and molded article thereof - Google Patents

Description

This invention relates to a polycarbonate resin composition having light-guiding properties and a molded article made therefrom. More specifically, it relates to a polycarbonate resin composition and a molded article made therefrom that exhibits excellent light-guiding properties, minimal yellowing during molding, minimal degradation in humid and hot environments, and excellent fluidity, making it suitable for use in optical elements such as light guide plates, or in display panels and lighting covers.

LED-based light sources are attracting attention as next-generation light sources due to their energy efficiency and long lifespan. Since the development of blue light-emitting diodes in the 1990s, the practical potential of white light illumination using LEDs has increased, and commercially available products have rapidly appeared, mainly for localized illumination. Furthermore, for surface light sources such as displays, LED light sources offer the advantage of higher color purity compared to the colors (red, green, and blue) obtained by transmitting white light emitted by cold cathode fluorescent lamps through color filters. This significantly expands the range of color reproduction, leading to a trend towards LED light sources.

On the other hand, because LEDs are point light sources, illuminating a large area requires many LEDs to be placed on the back of the light source (backlight method), and each of these LEDs appears as a point light source, resulting in uneven illumination. Recently, to eliminate this unevenness, and to achieve lower costs, further power savings, and thinner products, there has been an increase in so-called edge-lit light sources where LEDs are placed on the edge of the light source.

In edge-lit light sources, a light guide is used to transmit light over long distances to achieve uniform surface illumination. However, edge-lit light sources have the problem of becoming dimmer as the distance from the light source increases. Therefore, materials for molded bodies with light-guiding properties require characteristics that minimize light attenuation from the light source, i.e., good light-guiding properties. Among transparent resins, polymethyl methacrylate (hereinafter sometimes referred to as "PMMA") has been used as the most suitable material. However, PMMA does not always have sufficient impact resistance and thermal stability, which limits its use in the aforementioned applications. Furthermore, with the shift to LED light sources, heat resistance has also become a requirement for light guides in addition to the above characteristics. Therefore, technologies to improve the light-guiding properties of polycarbonate resin, which excels in heat resistance and impact resistance, have attracted attention. In addition, to achieve thinner products, high fluidity is required in the molten resin to maintain improved light-guiding properties while ensuring excellent processability for injection molding, extrusion molding, or compression molding.

As an example of improving the light-guiding properties of polycarbonate, Patent Document 1 reports an aromatic polycarbonate resin composition for light guide plates, in which a specific phosphorus-based stabilizer and mold release agent are blended into a polycarbonate resin with a viscosity-average molecular weight of 13,000 to 15,000. However, in addition to problems with strength, there is also the problem of reduced heat and humidity resistance due to the phosphorus-based stabilizer, which limits its applications.

Patent documents 2 and 3 report aromatic polycarbonate resin compositions for light guide plates containing small amounts of specific siloxane compounds. However, silicone-based compounds may generate low-molecular-weight silicone gas under high-temperature conditions.

Patent Document 4 reports a light guide plate having a light scattering layer on the surface or back surface of a plate-shaped molded body formed using a resin composition consisting of polycarbonate and an acrylic resin. Patent Document 5 reports an aromatic polycarbonate resin composition consisting of an aromatic polycarbonate resin and another thermoplastic resin having a refractive index difference of 0.001 or more compared to the aromatic polycarbonate resin. However, because an acrylic resin, which is inherently immiscible with polycarbonate resin, is added, the amount added is limited, and the light-guiding properties may not be fully realized.

Japanese Patent Publication No. 2007-204737 Japanese Patent Publication No. 2004-250557 Japanese Patent Publication No. 2015-157901 Japanese Patent Application Publication No. 10-73725 Japanese Patent Publication No. 2002-60609

The object of the present invention is to provide a polycarbonate resin composition and a molded article made therefrom that exhibits excellent light-guiding properties, minimal yellowing during molding, minimal degradation in humid and hot environments, and excellent fluidity.

As a result of diligent research aimed at achieving the above objective, the inventors of the present invention discovered that a polycarbonate resin composition comprising a specific polyether polymer and/or polyoxyalkylene bisphenol A ether, preferably further comprising a specific phosphorus compound, in a specific proportion to a polycarbonate resin achieves the above objective, and thus arrived at the present invention.
In other words, the present invention provides the following configurations (1) to (6).

(1) A polycarbonate resin composition having light-guiding properties, characterized by containing (A) 100 parts by weight of polycarbonate resin (component A), and (B) 0.2 to 1.5 parts by weight of a polyether polymer having an alkyl group at at least one terminal having a number average molecular weight of 300 to 3,500 and/or polyoxyalkylene bisphenol A ether (component B) having a number average molecular weight of 300 to 2,000.
(2) A polycarbonate resin composition having the light-guiding performance described in item 1, wherein component B is at least one polyether polymer selected from the group consisting of polyethers having an alkyl group at at least one terminal represented by the following formula [1] and/or the following formula [2].

(In the formula, m is an integer between 10 and 18, and n is an integer between 5 and 40.)

(In the formula, m is an integer between 12 and 18, and n is an integer between 4 and 50.)
(3) A polycarbonate resin composition having the light-guiding performance described in item 1 above, wherein component B is a polyoxyalkylene bisphenol A ether represented by the following formula [3].

(In the formula, OR' represents ethylene oxide or propylene oxide, and n is an integer between 3 and 20.)
(4) A polycarbonate resin composition having the light-guiding performance described in item 1 above, comprising 0.01 to 0.1 parts by weight of (C) a phosphorus-based compound having a phenyl group (component C) per 100 parts by weight of (A) polycarbonate resin (component A).
(5) A polycarbonate resin composition having the light-guiding performance described in item (4) above, wherein component C is a phosphorus-based compound having three phenyl groups represented by the following formula [4].

(6) A molded article made from a polycarbonate resin composition having the light-guiding properties described in item 1 above.

The polycarbonate resin composition of the present invention exhibits excellent light-guiding properties, minimal yellowing during molding, low degradation in humid and hot environments, and superior fluidity. Because of these effects, the polycarbonate resin composition of the present invention is extremely useful in various industrial applications, including lighting (including LED lighting), office automation equipment, electrical and electronic equipment, and the automotive industry, and its industrial benefits are extremely significant.

The details of this invention will be described below.

<Component A: Polycarbonate resin>
The polycarbonate resin used as component A in this invention is typically obtained by reacting a dihydroxy compound with a carbonate precursor by interfacial polycondensation or melt transesterification, or by polymerizing a carbonate prepolymer by solid-phase transesterification, or by polymerizing a cyclic carbonate compound by ring-opening polymerization.

The dihydroxy component used here can be any dihydroxy component commonly used in polycarbonate resins, and may be either bisphenols or aliphatic diols.

Examples of bisphenols include 4,4'-dihydroxybiphenyl, bis(4-hydroxyphenyl)methane, 1,1-bis(4-hydroxyphenyl)ethane, 1,1-bis(4-hydroxyphenyl)-1-phenylethane, 2,2-bis(4-hydroxyphenyl)propane, 2,2-bis(4-hydroxy-3-methylphenyl)propane, 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane, 2,2-bis(4-hydroxy-3,3'-biphenyl)propane, 2,2-bis(4-hydroxy-3-isopropylphenyl)propane, and 2,2-bis(3-t-butyl-4-hydroxyphenyl)propane. , 2,2-bis(4-hydroxyphenyl)butane, 2,2-bis(4-hydroxyphenyl)octane, 2,2-bis(3-bromo-4-hydroxyphenyl)propane, 2,2-bis(3,5-dimethyl-4-hydroxyphenyl)propane, 2,2-bis(3-cyclohexyl-4-hydroxyphenyl)propane, 1,1-bis(3-cyclohexyl-4-hydroxyphenyl)cyclohexane, bis(4-hydroxyphenyl)diphenylmethane, 9,9-bis(4-hydroxyphenyl)fluorene, 9,9-bis(4-hydroxy-3-methylphenyl)fluorene, 1,1-bis(4-hydroxyphenyl)cyclohexane, 1,1- Bis(4-hydroxyphenyl)cyclopentane, 4,4'-dihydroxydiphenyl ether, 4,4'-dihydroxy-3,3'-dimethyldiphenyl ether, 4,4'-sulfonyldiphenol, 4,4'-dihydroxydiphenyl sulfoxide, 4,4'-dihydroxydiphenyl sulfide, 2,2'-dimethyl-4,4'-sulfonyldiphenol, 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfoxide, 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfide, 2,2'-diphenyl-4,4'-sulfonyldiphenol, 4,4'-dihydroxy-3,3'-diphenyldiphenyl sulfoxide, 4, Examples include 4'-dihydroxy-3,3'-diphenyldiphenyl sulfide, 1,3-bis{2-(4-hydroxyphenyl)propyl}benzene, 1,4-bis{2-(4-hydroxyphenyl)propyl}benzene, 1,4-bis(4-hydroxyphenyl)cyclohexane, 1,3-bis(4-hydroxyphenyl)cyclohexane, 4,8-bis(4-hydroxyphenyl)tricyclo[5.2.1.02,6]decane, 4,4'-(1,3-adamantanediyl)diphenol, 1,3-bis(4-hydroxyphenyl)-5,7-dimethyladamantane, and bisphenol compounds having a siloxane structure represented by the following formula [5].

[In the formula, ^R3 and ^R4 are each independently a hydrogen atom, a halogen atom, an alkyl group having 1 to 10 carbon atoms, and an alkoxy group having 1 to 10 carbon atoms; ^R5 , ^R6 , ^R7 , ^R8 , ^R9 , and ^R10 are each independently a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 12 carbon atoms; p and q are each integers from 1 to 4; e is a natural number; f is 0 or a natural number; and e + f is a natural number less than 100. X is a divalent aliphatic group having 2 to 8 carbon atoms.]

Examples of aliphatic diols include 2,2-bis-(4-hydroxycyclohexyl)-propane, 1,14-tetradecanediol, octaethylene glycol, 1,16-hexadecanediol, 4,4'-bis(2-hydroxyethoxy)biphenyl, bis{(2-hydroxyethoxy)phenyl}methane, 1,1-bis{(2-hydroxyethoxy)phenyl}ethane, 1,1-bis{(2-hydroxyethoxy)phenyl}-1-phenylethane, 2,2-bis{(2-hydroxyethoxy)phenyl}propane, 2,2-bis{(2-hydroxyethoxy)-3-methylphenyl}propane, 1,1-bis(2-hydroxyethoxy)phenyl}-3,3,5-trimethylcyclohexane, and 2,2-bis{4-(2-hydroxyethoxy) )-3,3'-biphenyl}propane, 2,2-bis{(2-hydroxyethoxy)-3-isopropylphenyl}propane, 2,2-bis{3-t-butyl-4-(2-hydroxyethoxy)phenyl}propane, 2,2-bis{(2-hydroxyethoxy)phenyl}butane, 2,2-bis{(2-hydroxyethoxy)phenyl}-4-methylpentane, 2,2-bis{(2-hydroxyethoxy)phenyl}octane, 1,1-bis{(2-hydroxyethoxy)phenyl}decane, 2,2-bis{3-bromo-4-(2-hydroxyethoxy)phenyl}propane, 2,2-bis{3,5-dimethyl-4-(2-hydroxyethoxy)phenyl}propane, 2,2-bis{3-cyclohexyl-4-(2-hydroxyethoxy)phenyl} Propane, 1,1-bis{3-cyclohexyl-4-(2-hydroxyethoxy)phenyl}cyclohexane, bis{(2-hydroxyethoxy)phenyl}diphenylmethane, 9,9-bis{(2-hydroxyethoxy)phenyl}fluorene, 9,9-bis{4-(2-hydroxyethoxy)-3-methylphenyl}fluorene, 1,1-bis{(2-hydroxyethoxy)phenyl}cyclohexane, 1,1-bis{(2-hydroxyethoxy)phenyl}cyclopentane, 4,4'-bis(2-hydroxyethoxy)diphenyl ether, 4,4'-bis(2-hydroxyethoxy)-3,3'-dimethyldiphenyl ether, 1,3-bis[2-{(2-hydroxyethoxy)phenyl}propyl]benzene, 1,4-bis[2-{(2- Examples include hydroxyethoxy)phenyl}propyl]benzene, 1,4-bis{(2-hydroxyethoxy)phenyl}cyclohexane, 1,3-bis{(2-hydroxyethoxy)phenyl}cyclohexane, 4,8-bis{(2-hydroxyethoxy)phenyl}tricyclo[5.2.1.02,6]decane, 1,3-bis{(2-hydroxyethoxy)phenyl}-5,7-dimethyladamantane, 3,9-bis(2-hydroxy-1,1-dimethylethyl)-2,4,8,10-tetraoxaspiro(5,5)undecane, 1,4:3,6-dianhydro-D-sorbitol (isosorbide), 1,4:3,6-dianhydro-D-mannitol (isomannide), 1,4:3,6-dianhydro-L-iditol (isoidide), etc.

Among these, aromatic bisphenols are preferred, particularly 1,1-bis(4-hydroxyphenyl)-1-phenylethane, 2,2-bis(4-hydroxyphenyl)propane, 2,2-bis(4-hydroxy-3-methylphenyl)propane, 1,1-bis(4-hydroxyphenyl)cyclohexane, 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane, 4,4'-sulfonyldiphenol, 2,2'-dimethyl-4,4'-sulfonyldiphenol, and 9,9-bis(4-hydroxy-3-methylphenyl) Bisphenol compounds represented by the general formula [4] are preferred, particularly 2,2-bis(4-hydroxyphenyl)propane, 1,1-bis(4-hydroxyphenyl)cyclohexane, 4,4'-sulfonyldiphenol, 9,9-bis(4-hydroxy-3-methylphenyl)fluorene, and the bisphenol compounds represented by the general formula [4]. Among these, 2,2-bis(4-hydroxyphenyl)propane is the most preferred due to its excellent strength and good durability. These may be used individually or in combination of two or more.

The polycarbonate resin used as component A of the present invention may be a branched polycarbonate resin by using a branching agent in combination with the above-mentioned dihydroxy compound. Examples of the three- or more polyfunctional aromatic compounds used in such branched polycarbonate resins include phloroglucin, phloroglucid, or 4,6-dimethyl-2,4,6-tris(4-hydroxyphenyl)heptene-2,2,4,6-trimethyl-2,4,6-tris(4-hydroxyphenyl)heptane, 1,3,5-tris(4-hydroxyphenyl)benzene, 1,1,1-tris(4-hydroxyphenyl)ethane, 1,1,1-tris(3,5-dimethyl-4-hydroxyphenyl)ethane, 26-bis(2-hydroxy-5-methylbenzyl)-4-methylphenol, 4-{4-[1,1-bis(4- Examples include trisphenols such as hydroxyphenyl)ethyl]benzene}-α,α-dimethylbenzylphenol, tetra(4-hydroxyphenyl)methane, bis(2,4-dihydroxyphenyl)ketone, 1,4-bis(4,4-dihydroxytriphenylmethyl)benzene, or trimellitic acid, pyromellitic acid, benzophenonetetracarboxylic acid, and their acid chlorides. Among these, 1,1,1-tris(4-hydroxyphenyl)ethane and 1,1,1-tris(3,5-dimethyl-4-hydroxyphenyl)ethane are preferred, and 1,1,1-tris(4-hydroxyphenyl)ethane is particularly preferred.

These polycarbonate resins are produced by conventional aromatic polycarbonate resins using known reaction methods, such as reacting aromatic dihydroxy components with carbonate precursors like phosgene or diester carbonate. A brief explanation of the basic methods for their production is provided below.

In reactions using phosgene as a carbonate precursor, for example, the reaction is usually carried out in the presence of an acid binder and a solvent. Examples of acid binders include alkali metal hydroxides such as sodium hydroxide and potassium hydroxide, or amine compounds such as pyridine. Examples of solvents include halogenated hydrocarbons such as methylene chloride and chlorobenzene. Catalysts such as tertiary amines or quaternary ammonium salts can also be used to accelerate the reaction. The reaction temperature is usually 0 to 40°C, and the reaction time is several minutes to 5 hours. Transesterification reactions using diester carbonate as a carbonate precursor are carried out by heating and stirring a predetermined proportion of aromatic dihydroxy components with diester carbonate under an inert gas atmosphere, and distilling off the resulting alcohol or phenol. The reaction temperature varies depending on the boiling point of the resulting alcohol or phenol, but is usually in the range of 120 to 300°C. The reaction is completed by distilling off the resulting alcohol or phenol under reduced pressure from the beginning. Catalysts commonly used in transesterification reactions can also be used to accelerate the reaction. Examples of diester carbonates used in the transesterification reaction include diphenyl carbonate, dinaphthyl carbonate, bis(diphenyl) carbonate, dimethyl carbonate, diethyl carbonate, and dibutyl carbonate. Of these, diphenyl carbonate is particularly preferred.

In this invention, an end-terminating agent is used in the polymerization reaction. The end-terminating agent is used to adjust the molecular weight, and the resulting polycarbonate resin has superior thermal stability compared to those without end-termination because their ends are sealed. Examples of such end-terminating agents include monofunctional phenols represented by the following formulas [6] to [8].

[In formula (6), A is a hydrogen atom, an alkyl group having 1 to 9 carbon atoms, an alkylphenyl group (the alkyl portion having 1 to 9 carbon atoms), a phenyl group, or a phenylalkyl group (the alkyl portion having 1 to 9 carbon atoms), and r is an integer from 1 to 5, preferably from 1 to 3.]

[In formula (8), Y is -R-O-, -R-CO-O-, or -R-O-CO-, where R represents a single bond or a divalent aliphatic hydrocarbon group having 1 to 10 carbon atoms, preferably 1 to 5, and n represents an integer from 10 to 50.]

Specific examples of monofunctional phenols represented by the above formula [6] include, for example, phenol, isopropylphenol, p-tert-butylphenol, p-cresol, p-cumylphenol, 2-phenylphenol, 4-phenylphenol, and isooctylphenol.

Furthermore, the monofunctional phenols represented by formulas [7] or [8] are phenols having long-chain alkyl groups or aliphatic ester groups as substituents. When these are used to seal the ends of polycarbonate resins, they not only function as end-terminating agents or molecular weight modifiers, but also improve the melt-flow properties of the resin, facilitating molding and processing, and reducing the resin's water absorption rate. Therefore, they are preferably used.

The substituted phenols in formula [7] above are preferably those in which n is 10 to 30, particularly 10 to 26. Specific examples include decylphenol, dodecylphenol, tetradecylphenol, hexadecylphenol, octadecylphenol, eicosylphenol, docosylphenol, and triacontylphenol.

Furthermore, suitable substituted phenols for formula [8] are compounds in which Y is -R-COO- and R is a single bond, with n being 10 to 30, particularly 10 to 26. Specific examples include decyl hydroxybenzoate, dodecyl hydroxybenzoate, tetradecyl hydroxybenzoate, hexadecyl hydroxybenzoate, eicosyl hydroxybenzoate, docosyl hydroxybenzoate, and triacontyl hydroxybenzoate.

Among these monofunctional phenols, the monofunctional phenol represented by formula [6] above is preferred, more preferably alkyl-substituted or phenylalkyl-substituted phenols, and particularly preferred are p-tert-butylphenol, p-cumylphenol, or 2-phenylphenol.

These monofunctional phenol end-terminating agents are preferably introduced at least 5 mol%, more preferably at least 10 mol%, of the total end-termination of the resulting polycarbonate resin. The end-terminating agents may be used individually or in combination of two or more types.

The polycarbonate resin used as component A in this invention may be a polyester carbonate copolymerized with an aromatic dicarboxylic acid, such as terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid, or a derivative thereof, as long as it does not impair the spirit of this invention.

The viscosity-average molecular weight of the polycarbonate resin used as component A in this invention is preferably in the range of 11,500 to 50,000, more preferably in the range of 12,500 to 40,000, even more preferably in the range of 13,500 to 35,000, and most preferably in the range of 15,000 to 30,000. If the molecular weight exceeds 50,000, the melt viscosity may become too high, resulting in poor moldability, and if the molecular weight is less than 11,500, problems may arise with mechanical strength. In this invention, the viscosity-average molecular weight is first determined by calculating the specific viscosity using the following formula from a solution obtained by dissolving 0.7 g of polycarbonate resin in 100 ml of methylene chloride at 20°C using an Ostwald viscometer, and then inserting the obtained specific viscosity into the following formula to determine the viscosity-average molecular weight Mv.
Specific viscosity (η _SP )=(t−t ₀ )/t ₀
[ _t0 is the number of seconds for the methylene chloride to fall, and t is the number of seconds for the sample solution to fall.]
η _SP /c = [η] + 0.45 × [η] ² c (where [η] is the intrinsic viscosity)
[η]=1.23×10 ⁻⁴ Mv ^0.83
c = 0.7

The polycarbonate resin used as component A in this invention preferably has a total chlorine (Cl) content of 0 to 500 ppm, more preferably 0 to 350 ppm. A total Cl content within this range is preferable because it provides excellent color and thermal stability.

<Component B: A specific polyether polymer and/or polyoxyalkylene bisphenol A ether>
The polycarbonate resin composition of the present invention contains a polyether polymer having a number average molecular weight of 300 to 3,500 and/or a polyoxyalkylene bisphenol A ether having a number average molecular weight of 300 to 2,000, which has an alkyl group at at least one end (preferably having a structure that is end-encapsulated with an alkyl group).

Polyether polymers are polyether polymers composed of units derived from alkylene glycols, and their alkylene groups may contain branched structures.

Preferably, the polyalkylene glycol is an alkylene glycol having 2 to 3 carbon atoms, such as ethylene glycol or propylene glycol. Furthermore, the polyalkylene glycol may be a homopolymer of a single alkylene glycol, or a random copolymer or block copolymer of two alkylene glycols.

Specifically, polyethylene glycol and polypropylene glycol are preferred as polyalkylene glycols. The polyalkylene glycol compounds used in this invention are characterized by having at least one end sealed with an alkyl group, as shown in formulas [1] and [2] below. The alkyl group preferably has 10 to 18 carbon atoms, more preferably 12 to 18 carbon atoms, and preferably does not contain unsaturated carbon bonds like an alkyl group.

(In the formula, m is an integer between 10 and 18, and n is an integer between 5 and 40.)

(In the formula, m is an integer between 12 and 18, and n is an integer between 4 and 50.)
Polyalkylene glycol compounds having an alkyl group at at least one terminal are obtained by addition polymerization of an alkylene oxide to an alkyl group-containing alcohol. Addition polymerization of alkylene oxides is well known and not particularly limited, but is generally carried out under an alkaline catalyst such as sodium hydroxide or potassium hydroxide.

The etherification method is well known and not particularly limited, but generally, it involves reacting polyalkylene glycol with an alcohol in the presence of metallic sodium, sodium hydride, sodium hydroxide, etc.

The number-average molecular weight of the polyether polymer, in which at least one end is encapsulated with an alkyl group, is in the range of 300 to 3,500, preferably 500 to 3,000, and more preferably 800 to 2,500. Exceeding this range results in poor resistance to humidity and heat, and a reduced effect on enhancing light-guiding properties. Below this range, the effect on enhancing fluidity is reduced, and adverse effects such as thermal decomposition of the polycarbonate resin occur. The number-average molecular weight of the polyether polymer is calculated based on the hydroxyl value measured in accordance with JIS K1577.

Furthermore, the polyoxyalkylene bisphenol A ether preferably has polyethylene oxide or polypropylene oxide at both ends of the bisphenol A structure, as shown in formula [3] below. The polyoxyalkylene structure is preferably such that the number n in formula [3] is an integer from 3 to 20, more preferably an integer from 5 to 18, and even more preferably an integer from 8 to 16.

(In the formula, OR' represents ethylene oxide or propylene oxide, and n is an integer between 3 and 20.)

The number-average molecular weight of polyoxyalkylene bisphenol A ether is in the range of 300 to 2,000, preferably 500 to 1,800, and more preferably 1,000 to 1,600. Exceeding this range results in poor resistance to humidity and heat, and a reduced effect on enhancing light-guiding properties. Below this range, the effect on enhancing fluidity is reduced. Note that the number-average molecular weight of polyoxyalkylene bisphenol A ether is calculated based on the hydroxyl value measured in accordance with JIS K1577.

The specific polyether polymer and/or polyoxyalkylene bisphenol A ether used as component B in this invention improves the light-guiding performance of the polycarbonate resin without impairing its mechanical properties, hue, and molding stability. The content of the specific polyether polymer and/or polyoxyalkylene bisphenol A ether is 0.2 to 1.5 parts by weight per 100 parts by weight of the polycarbonate resin (component A). Preferably, it is 0.4 to 1.3 parts by weight, and more preferably 0.5 to 1.2 parts by weight. If the content falls below this range, the improvement in transparency and fluidity is insufficient; if it exceeds this range, the resin becomes discolored, impairing the transparency of the polycarbonate and adversely affecting its heat resistance and mechanical strength.

<Component C: A phosphorus compound containing a phenyl group>
The phosphorus-based compound preferably used as component C of the present invention is a phosphorus-based compound having a phenyl group. Among these, a phosphorus-based compound having three phenyl groups is preferred, and triphenylphosphine represented by the following formula [4] is particularly preferred.

By using a phosphorus-based compound containing a phenyl group, high fluidity is imparted, and it also functions as an antioxidant. The content of the phosphorus-based compound containing a phenyl group (component C) is preferably 0.01 to 0.1 parts by weight, more preferably 0.02 to 0.08 parts by weight, per 100 parts by weight of the polycarbonate resin (component A). When the content is within this range, fluidity is improved, transparency is sufficiently enhanced as an antioxidant, and it does not adversely affect the heat resistance or mechanical strength of the polycarbonate resin.

<Other ingredients>
Other resins and fillers may be added to the polycarbonate resin composition of the present invention, as long as they do not impair transparency, light-guiding properties, etc. However, since many other resins and fillers interfere with transparency, this should be taken into consideration when selecting their type and quantity.

The polycarbonate resin composition of the present invention, while taking the above points into consideration, advantageously utilizes additives used for improvements in thermal stability, design properties, and other aspects. These additives will be specifically described below.

(I) Heat stabilizers The polycarbonate resin composition of the present invention may be blended with various known heat stabilizers. Specifically, examples include phosphorus-based antioxidants other than component C, phenol-based antioxidants, etc.

Specific examples of such phosphorus-based antioxidants include phosphorous acid (phosphite), phosphonite, phosphinite, phosphine, phosphoric acid (phosphate), phosphonate, phosphinate, and phosphine oxide, among which phosphite, phosphonite, phosphine, phosphonate, and phosphate are preferred. Specifically, examples of phosphite compounds include trimethyl phosphite, triethyl phosphite, tripropyl phosphite, triisopropyl phosphite, tributyl phosphite, triphenyl phosphite, tris(nonylphenyl) phosphite, tridecyl phosphite, trioctyl phosphite, trioctadecyl phosphite, didecyl monophenyl phosphite, dioctyl monophenyl phosphite, diisopropyl monophenyl phosphite, and monobutyl diphenyl phosphite. Examples include yl phosphite, monodecyldiphenyl phosphite, monooctyldiphenyl phosphite, 2,2-methylenebis(4,6-di-tert-butylphenyl)octyl phosphite, tris(diethylphenyl) phosphite, tris(di-iso-propylphenyl) phosphite, tris(di-n-butylphenyl) phosphite, tris(2,4-di-tert-butylphenyl) phosphite, and tris(2,6-di-tert-butylphenyl) phosphite. Furthermore, other phosphite compounds that react with divalent phenols to form cyclic structures can also be used. For example, 2,2'-methylenebis(4,6-di-tert-butylphenyl)(2,4-di-tert-butylphenyl) phosphite, 2,2'-methylenebis(4,6-di-tert-butylphenyl)(2-tert-butyl-4-methylphenyl) phosphite, 2,2'-methylenebis(4-methyl-6-tert-butylphenyl)(2-tert-butyl-4-methylphenyl) phosphite, and 2,2'-ethylidenebis(4-methyl-6-tert-butylphenyl)(2-tert-butyl-4-methylphenyl) phosphite are examples of such phosphate groups.

Examples of phosphonite compounds include 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-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)-4-phenyl-phenylphosphonite, and bis Examples include (2,4-di-tert-butylphenyl)-3-phenyl-phenylphosphonite, bis(2,6-di-n-butylphenyl)-3-phenyl-phenylphosphonite, bis(2,6-di-tert-butylphenyl)-4-phenyl-phenylphosphonite, and bis(2,6-di-tert-butylphenyl)-3-phenyl-phenylphosphonite. Tetrakis(di-tert-butylphenyl)-biphenylenediphosphonite and bis(di-tert-butylphenyl)-phenyl-phenylphosphonite are preferred, and tetrakis(2,4-di-tert-butylphenyl)-biphenylenediphosphonite and bis(2,4-di-tert-butylphenyl)-phenyl-phenylphosphonite are more preferred. Such phosphonite compounds can be used in combination with phosphite compounds having aryl groups substituted with two or more alkyl groups, and this is preferable.

Examples of phosphine compounds other than triphenylphosphine (component C) include triethylphosphine, tripropylphosphine, tributylphosphine, trioctylphosphine, triamylphosphine, dimethylphenylphosphine, dibutylphenylphosphine, diphenylmethylphosphine, diphenyloctylphosphine, tri-p-tolylphosphine, trinaphthylphosphine, and diphenylbenzylphosphine. Triphenylphosphine is a particularly preferred phosphine compound.

Examples of phosphonate compounds include dimethyl benzenephosphonate, diethyl benzenephosphonate, and dipropyl benzenephosphonate.

Examples of phosphate compounds include tributyl phosphate, trimethyl phosphate, tricresyl phosphate, triphenyl phosphate, trichlorophenyl phosphate, triethyl phosphate, diphenyl cresyl phosphate, diphenyl monoorthoxenyl phosphate, tributoxyethyl phosphate, dibutyl phosphate, dioctyl phosphate, and diisopropyl phosphate, with triphenyl phosphate and trimethyl phosphate being preferred.

Specific examples of phenolic antioxidants include, for example, vitamin E, n-octadecyl-β-(4'-hydroxy-3',5'-di-tert-butylphenol)propionate, 2-tert-butyl-6-(3'-tert-butyl-5'-methyl-2'-hydroxybenzyl)-4-methylphenyl acrylate, 2,6-di-tert-butyl-4-(N,N-dimethylaminomethyl)phenol, 3,5-di-tert-butyl-4-hydroxybenzylphosphonate diethyl ester, 2,2'-methylenebis(4-methyl-6-tert-butylphenol), 2,2'-methylenebis(4-ethyl-6-tert-butylphenol), 4,4'-methylenebis(2,6-di-tert-butylphenol), 2,2'-methylenebis(4-methyl-6-cyclohexylphenol), and 2,2'-dimethylenebis(6- α-methyl-benzyl-p-cresol)2,2'-ethylidene-bis(4,6-di-tert-butylphenol),2,2'-butylidene-bis(4-methyl-6-tert-butylphenol),4,4'-butylidenebis(3-methyl-6-tert-butylphenol),triethylene glycol-N-bis-3-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionate, 1,6 -Hexanediol bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, bis[2-tert-butyl-4-methyl6-(3-tert-butyl-5-methyl-2-hydroxybenzyl)phenyl]terephthalate, 3,9-bis{2-[3-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionyloxy]-1,1,-dimethylethyl}-2,4,8, 10-Tetraoxaspiro[5,5]undecane, 4,4'-thiobis(6-tert-butyl-m-cresol), 4,4'-thiobis(3-methyl-6-tert-butylphenol), 2,2'-thiobis(4-methyl-6-tert-butylphenol), bis(3,5-di-tert-butyl-4-hydroxybenzyl) sulfide, 4,4'-di-thiobis(2,6-di-tert-butylphenol) , 4,4'-trithiobis(2,6-di-tert-butylphenol), 2,4-bis(n-octylthio)-6-(4-hydroxy-3',5'-di-tert-butylanilino)-1,3,5-triazine, N,N'-hexamethylenebis-(3,5-di-tert-butyl-4-hydroxyhydrocinnamide), N,N'-bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propio Examples of suitable and preferable alternatives include [nyl]hydrazine, 1,1,3-tris(2-methyl-4-hydroxy-5-tert-butylphenyl)butane, 1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene, tris(3,5-di-tert-butyl-4-hydroxyphenyl)isocyanurate, tris(3,5-di-tert-butyl-4-hydroxybenzyl)isocyanurate, 1,3,5-tris(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl)isocyanurate, 1,3,5-tris-2[3(3,5-di-tert-butyl-4-hydroxyphenyl)propionyloxy]ethyl isocyanurate, and tetrakis[methylene-3-(3',5'-di-tert-butyl-4-hydroxyphenyl)propionate]methane.

Among these, n-octadecyl-β-(4'-hydroxy-3',5'-di-tert-butylfel)propionate, 2-tert-butyl-6-(3'-tert-butyl-5'-methyl-2'-hydroxybenzyl)-4-methylphenyl acrylate, 3,9-bis{2-[3-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionyloxy]-1,1,-dimethylethyl}-2,4,8,10-tetraoxaspiro[5,5]undecane, and tetrakis[methylene-3-(3',5'-di-tert-butyl-4-hydroxyphenyl)propionate]methane are preferred, and n-octadecyl-β-(4'-hydroxy-3',5'-di-tert-butylfel)propionate is even more preferred.

The phosphorus-based antioxidants and phenol-based antioxidants listed above can be used individually or in combination of two or more. The content of each phosphorus-based or phenol-based antioxidant is preferably 0.0001 to 1 part by weight per 100 parts by weight of component A. More preferably, it is 0.0005 to 0.5 parts by weight, and even more preferably 0.001 to 0.2 parts by weight.

Furthermore, since the moisture and heat resistance of the polycarbonate resin decreases when the amount of phosphorus-based antioxidants, especially phosphite-based antioxidants, is increased, the amount is preferably less than 0.02 parts by weight, more preferably 0.015 parts by weight or less, even more preferably 0.01 parts by weight or less, particularly preferably 0.005 parts by weight or less, and most preferably 0.001 parts by weight or less. It is also preferable to substantially omit the antioxidants.

(II) Release Agents Release agents may be added to the polycarbonate resin composition of the present invention as needed. Any known release agents can be used. For example, saturated fatty acid esters, unsaturated fatty acid esters, polyolefin waxes (such as polyethylene wax or 1-alkene polymers; these can also be modified with functional group-containing compounds such as acid modification), silicone compounds, fluorine compounds, paraffin wax, beeswax, etc. Among these, saturated fatty acid esters, linear or cyclic polydimethylsiloxane oil, polymethylphenyl silicone oil, and fluorine oil are preferred. Particularly preferred release agents include saturated fatty acid esters, such as monoglycerides like monoglyceride stearate, polyglycerin fatty acid esters like decaglycerin decastearate and decaglycerin tetrastearate, lower fatty acid esters like stearate stearate, higher fatty acid esters like behenate sebacate, and erythritol esters like pentaerythritol tetrastearate. The amount of such release agent is preferably 0.01 to 1 part by weight per 100 parts by weight of component A.

(III) UV absorbers The polycarbonate resin composition of the present invention may contain UV absorbers as needed. Examples of such UV absorbers include benzophenone-based UV absorbers such as 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-n-octoxybenzophenone, 2-hydroxy-4-n-dodecyloxybenzophenone, 2-hydroxy-4-bendyloxybenzophenone, 2,2'-dihydroxy-4-methoxybenzophenone, 2-hydroxy-4-methoxy-2'-carboxybenzophenone, 2-hydroxy-4-methoxy-5-sulfoxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2,2',4,4'-tetrahydroxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxy-5-sodium sulfoxybenzophenone, and bis(5-benzoyl-4-hydroxy-2-methoxyphenyl)methane.

Examples of UV absorbers include 2-(2'-hydroxy-5'-methylphenyl)benzotriazole, 2-(2'-hydroxy-5'-tert-butylphenyl)benzotriazole, 2-(2'-hydroxy-5'-tert-octylphenyl)benzotriazole, 2-(2'-hydroxy-3',5'-di-tert-butylphenyl)benzotriazole, 2-(2'-hydroxy-3',5'-di-tert-amylphenyl)benzotriazole, 2-(2'-hydroxy-3'-dodecyl-5'-methylphenyl)benzotriazole, 2-(2'-hydroxy-3',5'-bis(α,α'-dimethylbenzyl)phenylbenzotriazole, 2-[2'-hydroxy-3'-( Benzotriazole-based ultraviolet absorbers can be exemplified by condensates of 3'', 4'', 5'', 6'', tetraphthalimidomethyl)-5'-methylphenyl]benzotriazole, 2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole, 2'-hydroxy-3',5'-di-tert-butylphenyl)-5-chlorobenzotriazole, 2,2'methylenebis[4-(1,1,3,3-tetramethylbutyl)-6-(2H-benzotriazole-2-yl)phenol], and methyl-3-[3-tert-butyl-5-(2H-benzotriazole-2-yl)-4-hydroxyphenylpropionate-polyethylene glycol].

Furthermore, examples of UV absorbers include hydroxyphenyltriazine compounds such as 2-(4,6-diphenyl-1,3,5-triazine-2-yl)-5-hexyloxyphenol and 2-(4,6-bis-(2,4-dimethylphenyl-1,3,5-triazine-2-yl)-5-hexyloxyphenol, as well as malonic acid ester compounds such as Hostavin PR-25 and Hostavin B-CAP, both manufactured by Clariant Japan.

The amount of UV absorber is preferably 0.01 to 5 parts by weight, and more preferably 0.02 to 1 part by weight, per 100 parts by weight of component A.

(IV) Light stabilizers The polycarbonate resin composition of the present invention may contain light stabilizers as needed. Examples of such light stabilizers include bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis(1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, bis(1,2,2,6,6-pentamethyl-4-piperidyl)-2-(3,5-di-tert-butyl-4-hydroxybenzyl)-2n-butylmalonate, a condensate of 1,2,3,4-butanecarboxylic acid, 2,2,6,6-tetramethyl-4-piperidinol, and tridecyl alcohol, and 1,2,3,4-butanedicarboxylic acid and 1,2,2,6,6- Condensate of pentamethyl-4-piperidinol and tridecyl alcohol, tetrakis(2,2,6,6-tetramethyl-4-piperidyl)-1,2,3,4-butanetetracarboxylate, tetrakis(1,2,2,6,6-pentamethyl-4-piperidyl)-1,2,3,4-butanetetracarboxylate, poly{[6-(1,1,3,3-tetramethylbutyl)amino-1,3,5-triazine-2,4-diyl][(2,2,6,6-tetramethylpiperidyl)imino]hexamethylene[(2,2,6,6-tetramethylpi [peridyl)imino]}, poly{[6-morpholino-s-triazine-2,4-diyl][(2,2,6,6-tetramethylpiperidyl)imino]hexamethylene[(2,2,6,6-tetramethylpiperidyl)imino]}, condensate of 1,2,3,4-butanetetracarboxylic acid and 2,2,6,6-tetramethyl-4-piperidinol and β,β,β',β'-tetramethyl-3,9-(2,4,8,10-tetraoxaspiro[5,5]undecane)diethanol, N,N'-bis(3-aminopropyl)ethylenediamine and 2,4- Examples of hindered amines include a condensate of bis[N-butyl-N-(1,2,2,6,6-pentamethyl-4-piperidyl)amino]-chloro-1,3,5-triazine, a condensate of 1,2,3,4-butanetetracarboxylic acid, 1,2,2,6,6-pentamethyl-4-piperidinol, and β,β,β',β'-tetramethyl-3,9-(2,4,8,10-tetraoxaspiro[5,5]undecane)diethanol, and polymethylpropyl 3-oxy-[4-(2,2,6,6-tetramethyl)piperidinyl]siloxane. The content of the light stabilizer is preferably 0.01 to 5 parts by weight, more preferably 0.02 to 1 part by weight, per 100 parts by weight of component A.

(V) Bluing Agent The polycarbonate resin composition of the present invention may contain a bluing agent to counteract the yellowing caused by ultraviolet absorbers, etc. Any bluing agent commonly used for polycarbonate resins can be used without any particular problems. Generally, anthraquinone dyes are readily available and preferred. Specific bluing agents include, for example, Solvent Violet 13 [CA. No. (Color Index No.) 60725; Trademark name: "Macrolex Violet B" manufactured by Bayer, "Diarezin Blue G" manufactured by Mitsubishi Chemical Corporation, "Sumiplast Violet B" manufactured by Sumitomo Chemical Co., Ltd.], Solvent Violet 31 [CA. No. 68210; Trademark name: "Diarezin Violet D" manufactured by Mitsubishi Chemical Corporation], and Solvent Violet 33 [CA. Examples include No. 60725; trademark name "Diarezin Blue J" manufactured by Mitsubishi Chemical Corporation, generic name Solvent Blue 94 [CA. No. 61500; trademark name "Diarezin Blue N" manufactured by Mitsubishi Chemical Corporation], generic name Solvent Violet 36 [CA. No. 68210; trademark name "Macrolex Violet 3R" manufactured by Bayer AG], generic name Solvent Blue 97 [trademark name "Macrolex Blue RR" manufactured by Bayer AG], and generic name Solvent Blue 45 [CA. No. 61110; trademark name "Terazol Blue RLS" manufactured by Sandoz], with Macrolex Blue RR, Macrolex Violet B, and Terazol Blue RLS being particularly preferred. The bluing agent content is preferably 0.000005 to 0.001 parts by weight per 100 parts by weight of component A, and more preferably 0.00001 to 0.0001 parts by weight.

(VI) Fluorescent Whitening Agent In the polycarbonate resin composition of the present invention, the fluorescent whitening agent is not particularly limited as long as it is used to improve the color tone of the resin, etc., to white or bluish-white. Examples include stilbene-based, benzimidazole-based, benzoxazole-based, naphthalimide-based, rhodamine-based, coumarin-based, and oxazine-based compounds. Specifically, examples include CI Fluorescent Brightener 219:1, EASTOBRITE OB-1 manufactured by Eastman Chemical Company, and "Hakkoll PSR" manufactured by Hakkoll Chemical Company. Here, the fluorescent whitening agent has the effect of absorbing the ultraviolet energy of light rays and radiating this energy to the visible region. The content of the fluorescent whitening agent is preferably 0.001 to 0.1 parts by weight, and more preferably 0.001 to 0.05 parts by weight, per 100 parts by weight of component A.

(VII) Epoxy Compounds The polycarbonate resin composition of the present invention may contain epoxy compounds as needed. Such epoxy compounds are added for the purpose of suppressing mold corrosion, and basically all epoxy compounds having epoxy functional groups can be used. Specific examples of preferred epoxy compounds include 3,4-epoxycyclohexylmethyl-3',4'-epoxycyclohexylcarboxylate, 1,2-epoxy-4-(2-oxyranyl)cyclosexane adduct of 2,2-bis(hydroxymethyl)-1-butanol, copolymers of methyl methacrylate and glycidyl methacrylate, copolymers of styrene and glycidyl methacrylate, and the like. The amount of such epoxy compound added is preferably 0.003 to 0.2 parts by weight, more preferably 0.004 to 0.15 parts by weight, and even more preferably 0.005 to 0.1 parts by weight, per 100 parts by weight of component A.

(VIII) Organometallic Salts The polycarbonate resin composition of the present invention may contain organometallic salt compounds. Such organometallic salts are added for the purpose of imparting flame retardancy, and are preferably alkali (earth) metal salts of organic acids having 1 to 50 carbon atoms, preferably 1 to 40, and more preferably alkali (earth) metal salts of organic sulfonic acids. These alkali (earth) metal salts of organic sulfonic acids include metal salts of fluorine-substituted alkyl sulfonic acids, such as metal salts of perfluoroalkyl sulfonic acids having 1 to 10 carbon atoms, preferably 2 to 8, and alkali metals or alkaline earth metals, and metal salts of aromatic sulfonic acids having 7 to 50 carbon atoms, preferably 7 to 40, and alkali metals or alkaline earth metals. Examples of alkali metals constituting the metal salts include lithium, sodium, potassium, rubidium, and cesium, and examples of alkaline earth metals include beryllium, magnesium, calcium, strontium, and barium. More preferably alkali metals. Among these alkali metals, rubidium and cesium, which have larger ionic radii, are suitable when transparency is a higher requirement. However, these are not commonly used and are difficult to purify, which can result in cost disadvantages. On the other hand, metals with smaller ionic radii, such as lithium and sodium, may be disadvantageous in terms of flame retardancy. Considering these factors, the alkali metal used in alkali metal sulfonates can be selected accordingly, but potassium sulfonates, which offer an excellent balance of properties in all respects, are the most suitable. It is also possible to use potassium sulfonates in combination with alkali metal sulfonates composed of other alkali metals.

Specific examples of alkali metal salts of perfluoroalkyl sulfonates include potassium trifluoromethanesulfonate, potassium perfluorobutanesulfonate, potassium perfluorohexanesulfonate, potassium perfluorooctanesulfonate, sodium pentafluoroethanesulfonate, sodium perfluorobutanesulfonate, sodium perfluorooctanesulfonate, lithium trifluoromethanesulfonate, lithium perfluorobutanesulfonate, lithium perfluoroheptanesulfonate, cesium trifluoromethanesulfonate, cesium perfluorobutanesulfonate, cesium perfluorooctanesulfonate, cesium perfluorohexanesulfonate, rubidium perfluorobutanesulfonate, and rubidium perfluorohexanesulfonate, which can be used individually or in combination of two or more. Here, the number of carbon atoms in the perfluoroalkyl group is preferably in the range of 1 to 18, more preferably in the range of 1 to 10, and even more preferably in the range of 1 to 8. Among these, potassium perfluorobutanesulfonate is particularly preferred. Alkali (earth) metal perfluoroalkyl sulfonic acid salts, which are composed of alkali metals, usually contain a small amount of fluoride ions. The presence of such fluoride ions can reduce flame retardancy, so it is preferable to reduce them as much as possible. The proportion of such fluoride ions can be measured by ion chromatography. The fluoride ion content is preferably 100 ppm or less, more preferably 40 ppm or less, and particularly preferably 10 ppm or less. Furthermore, it is preferable that the content be 0.2 ppm or more for efficient manufacturing. Such alkali (earth) metal perfluoroalkyl sulfonic acid salts with reduced fluoride ion content can be manufactured using known manufacturing methods, by methods that reduce the amount of fluoride ions contained in the raw materials when manufacturing fluorine-containing organometallic salts, by methods that remove hydrogen fluoride obtained by the reaction using gases generated during the reaction or by heating, and by methods that reduce the amount of fluoride ions by using purification methods such as recrystallization and reprecipitation in the manufacturing of fluorine-containing organometallic salts. In particular, since organometallic salt-based flame retardants are relatively soluble in water, it is preferable to manufacture them using ion-exchanged water, especially water that satisfies an electrical resistance of 18 MΩ·cm or higher, i.e., an electrical conductivity of approximately 0.55 μS/cm or less, by dissolving and washing at a temperature higher than room temperature, and then cooling and recrystallizing them. Specific examples of alkali (earth) metal salts of aromatic sulfonic acids include, for example, disodium diphenyl sulfide-4,4'-disulfonate, dipotassium diphenyl sulfide-4,4'-disulfonate, potassium 5-sulfoisophthalate, sodium 5-sulfoisophthalate, polysodium polyethylene terephthalate polysulfonate, calcium 1-methoxynaphthalene-4-sulfonate, disodium 4-dodecylphenyl ether disulfonate, poly(2,6-dimethylphenylene oxide) polysulfonate, poly(1,3-phenylene oxide) polysulfonate, poly(1,4-phenylene oxide) polysulfonate, poly(2,6-diphenylphenylene oxide) polysulfonate, lithium poly(2-fluoro-6-butylphenylene oxide) polysulfonate, potassium benzenesulfonate, sodium benzenesulfonate, and benzenesulfonic acid. Examples include strontium, magnesium benzenesulfonate, dipotassium p-benzenedisulfonate, dipotassium naphthalene-2,6-disulfonate, calcium biphenyl-3,3'-disulfonate, sodium diphenylsulfon-3-sulfonate, potassium diphenylsulfon-3-sulfonate, dipotassium diphenylsulfon-3,3'-disulfonate, dipotassium diphenylsulfon-3,4'-disulfonate, sodium α,α,α-trifluoroacetophenone-4-sulfonate, dipotassium benzophenone-3,3'-disulfonate, disodium thiophene-2,5-disulfonate, dipotassium thiophene-2,5-disulfonate, calcium thiophene-2,5-disulfonate, sodium benzothiophenesulfonate, potassium diphenylsulfoxide-4-sulfonate, formalin condensates of sodium naphthalenesulfonate, and formalin condensates of sodium anthracenesulfonate. Among these alkali (earth) metal salts of aromatic sulfonic acids, potassium salts are particularly preferred. Of these alkali (earth) metal salts of aromatic sulfonic acids, potassium diphenylsulfon-3-sulfonate and dipotassium diphenylsulfon-3,3'-disulfonate are preferred, and mixtures thereof (with a weight ratio of 15/85 to 30/70) are particularly preferred.

Examples of organometallic salts other than alkali (earth) metal salts of sulfonic acid include alkali (earth) metal salts of sulfate esters and alkali (earth) metal salts of aromatic sulfonamides. Particularly noteworthy examples of alkali (earth) metal salts of sulfate esters include alkali (earth) metal salts of sulfate esters of monohydric and/or polyhydric alcohols. Examples of such sulfate esters of monohydric and/or polyhydric alcohols include methyl sulfate, ethyl sulfate, lauryl sulfate, hexadecyl sulfate, sulfate ester of polyoxyethylene alkylphenyl ether, mono, di, tri, and tetra sulfates of pentaerythritol, sulfate ester of lauric acid monoglyceride, sulfate ester of palmitic acid monoglyceride, and sulfate ester of stearate monoglyceride. Among these sulfate esters, alkali (earth) metal salts of lauryl sulfate are preferred. Examples of alkali (earth) metal salts of aromatic sulfonamides include saccharin, N-(p-tolylsulfonyl)-p-toluenesulfoimide, N-(N'-benzylaminocarbonyl)sulfanilimide, and alkali (earth) metal salts of N-(phenylcarboxyl)sulfanilimide. The content of the organometallic salt is preferably 0.001 to 1 part by weight, more preferably 0.005 to 0.5 parts by weight, even more preferably 0.01 to 0.3 parts by weight, and particularly preferably 0.03 to 0.15 parts by weight, per 100 parts by weight of component A.

(IX) Others In addition to the above, the resin composition of the present invention may contain known additives to impart various functions to molded articles or improve their properties, as long as the objectives of the present invention are not impaired. Examples of such additives include reinforcing fillers, lubricants (e.g., PTFE particles), colorants, fluorescent dyes, inorganic phosphors (e.g., phosphors with aluminate as the matrix crystal), antistatic agents, nucleating agents, inorganic and organic antimicrobial agents, photocatalytic antifouling agents (e.g., fine particle titanium dioxide, fine particle zinc oxide), light diffusing agents, flow modifiers, radical generators, infrared absorbers (heat absorbers), and photochromic agents.

<Regarding the manufacture of polycarbonate resin compositions>
Any method can be used to produce the polycarbonate resin composition of the present invention. For example, one method is to thoroughly mix component A, component B, and optionally other components using pre-mixing means such as a V-type blender, Henschel mixer, mechanochemical device, or extruder, then granulate as needed using an extruder or briquetting machine, and then melt-knead in a melt-kneader such as a vented twin-screw extruder, and then pelletize using equipment such as a pelletizer. Alternatively, one method is to supply component A, component B, and optionally other components independently to a melt-kneader such as a vented twin-screw extruder, to pre-mix component A and a portion of the other components and then supply them independently to the melt-kneader with the remaining components, to dilute and mix component B with water or an organic solvent and then supply it to the melt-kneader, or to pre-mix such diluted mixture with the other components and then supply it to the melt-kneader. If there is a liquid component to be blended, a so-called liquid injection device or liquid additive device can be used to supply it to the melt-kneader.

<Manufacturing of molded products>
Any method can be used to manufacture molded articles made from the polycarbonate resin composition of the present invention. For example, the polycarbonate resin composition can be kneaded in an extruder, Banbury mixer, or roll, and then molded by conventionally known methods such as injection molding, extrusion molding, or compression molding to obtain a molded article. Alternatively, a surface light source can be created by providing a light source on at least one side of a molded plate obtained by molding it into a plate shape, and installing a reflector on one side of the molded plate. As the light source for such a molded plate and surface light source, in addition to fluorescent lamps, self-emissive materials such as cold cathode tubes, LEDs, laser diodes, and organic ELs can be used. Molded plates and surface light sources obtained according to the present invention are used in mobile phones, mobile terminals, cameras, watches, laptop computers, displays, lighting, signals, automobile lamps, and display components for home appliances and optical equipment.
Furthermore, it is extremely useful for various industrial applications, including those in the fields of office automation equipment, electrical and electronic equipment, and automobiles.

Specifically, examples include covers for lighting, diffusers for displays, glass substitutes, various optical discs and related components, various housing molded products such as battery housings, lens barrels, memory cards, speaker cones, disc cartridges, surface light emitters, mechanical components for micromachines, molded products with hinges or molded products for hinges, light-transmitting and light-guiding buttons, and touch panel components.

The embodiment of the present invention that the inventors currently consider to be the best is a combination of the preferred ranges of the above-mentioned requirements, and a representative example is described in the following examples. Of course, the present invention is not limited to these embodiments.

The present invention will be further explained with reference to the following examples, but it is not limited to these examples. The details of each component used and their evaluation are as follows.
(Component A)
A: Bisphenol A type aromatic polycarbonate resin (Teijin Corporation: CM-1000, viscosity-average molecular weight 15,400)

(B component)
B-1: A polyether having an alkyl group with 12 carbon atoms at one end, polyethylene glycol, and/or polypropylene glycol structure (Pelletex PC-2421, manufactured by Miyoshi Oil & Fat Co., Ltd., number average molecular weight approximately 490).
B-2: A polyether with a polyethylene glycol structure, where one of the terminal atoms is an alkyl group with 16 or 18 carbon atoms (Pelletex 2828, manufactured by Miyoshi Oil & Fat Co., Ltd., number average molecular weight approximately 830).
B-3: Polyether having a polyethylene glycol structure with one end being an alkyl group having 12 or 14 carbon atoms (Pelletex 2465, manufactured by Miyoshi Oil & Fat Co., Ltd., number average molecular weight approximately 1,960)
B-4: A polyether having an alkyl group with 12 carbon atoms at one end, polyethylene glycol, and/or polypropylene glycol structure (Miyoshi Oil & Fat Co., Ltd. "Pelletex PC-2465", a polyether with a number average molecular weight of approximately 2,740).
B-5 (Comparative Example): A polyethylene glycol structure with a hydrocarbon group having 18 carbon atoms at one end and containing an unsaturated bond (Miyoshi Oil & Fat Co., Ltd.'s "Pelletex 2917H", a polyether with a number average molecular weight of approximately 360).
All of the above components B-1 to B-5 have been treated to remove alkali metals derived from metal catalysts that remain as impurities, while ensuring that their heat resistance and permeability are not compromised.
B-6: Polyoxyalkylene bisphenol A ether with 18 ethylene oxide groups (Bis-ol 18EN, manufactured by Toho Chemical Industry Co., Ltd., number average molecular weight approximately 1,010)
B-7: Polyoxyalkylene bisphenol A ether with 30 ethylene oxide units ("Bis-ol 30EN" manufactured by Toho Chemical Industry Co., Ltd., number average molecular weight approximately 1,600)

(C component)
C: Triphenylphosphine (manufactured by Johoku Chemical Industry Co., Ltd.: JC-263)
(Other ingredients)
(Release agent)
D: Glycerin monostearate (manufactured by Riken Vitamin Co., Ltd.: Rikemar S-100A)
(Evaluation method)
(1) Spectroscopic light transmittance The pellets obtained from each composition of the example were dried in a hot air circulation dryer at 120°C for 5 hours, and molded plates with a width of 50 mm, a length of 90 mm, and a thickness of 2 mm were formed using an injection molding machine [J85-ELIII manufactured by Japan Steel Works, Ltd.] at a molding temperature of 270°C and a mold temperature of 80°C. The spectral light transmittance of this 2 mm thick molded plate was measured at 1 nm intervals in the wavelength range of 200 nm to 800 nm using a spectrophotometer [Carry 5000 manufactured by Agilent Corporation]. The average spectral light transmittance in the wavelength range of 340 nm to 420 nm was calculated from the obtained spectral light transmittance.
A higher spectral light transmittance value indicates less light attenuation and superior light guiding performance. A spectral light transmittance of 87.0% or higher is marked with a circle (○), and a value below 87.0% is marked with a cross (×).

(2) Hue of molded sheet The pellets obtained from each composition of the example were dried at 120°C for 5 hours in a hot air circulation dryer, and molded sheets with a width of 50 mm, a length of 90 mm, and a thickness of 2 mm were formed using an injection molding machine [J85-ELIII manufactured by Japan Steel Works, Ltd.] at a molding temperature of 270°C and a mold temperature of 80°C. The hue (L*, a*, b*) of this 2 mm thick molded sheet was measured in accordance with JIS-K7105 using an integrating sphere spectrophotometer [CE-7000A manufactured by X-Rite Corporation] under the conditions of light source D65, field of view of 10 degrees, and transmission method.
A higher b* value for this molded plate indicates that the plate is more prone to yellowing. A b* value of 0.4 or less is marked with ○, and a value greater than 0.4 is marked with ×.

(3) Moisture and Heat Resistance The pellets obtained from each composition of the examples were dried at 120°C for 5 hours in a hot air circulation dryer, and molded plates with a width of 50 mm, a length of 90 mm, and a thickness of 2 mm were formed using an injection molding machine [J85-ELIII manufactured by Japan Steel Works, Ltd.] at a molding temperature of 270°C and a mold temperature of 80°C. These molded plates were subjected to moist heat treatment (temperature 120°C, 24 hours) using a steam sterilizer [SN-510 manufactured by Yamato Scientific Co., Ltd.], and the haze and viscosity-average molecular weight (Mv) were measured before and after the moist heat treatment. The haze of the molded plates was measured according to JIS-K7361-1, and the viscosity-average molecular weight (Mv) was measured by the method described below.

Measurement of Viscosity-Average Molecular Weight (Mv) The specific viscosity (η _SP ), calculated using the following formula, was determined using an Ostwald viscometer from a solution of polycarbonate resin dissolved in 100 ml of methylene chloride at 20°C. From the determined specific viscosity (η _SP ), the viscosity-average molecular weight Mv was calculated using the following formula.
Specific viscosity (η _SP )=(t−t ₀ )/t ₀
[ _t0 is the number of seconds for the methylene chloride to fall, and t is the number of seconds for the sample solution to fall.]
η _SP /c = [η] + 0.45 × [η] ² c (where [η] is the intrinsic viscosity)
[η]=1.23×10 ⁻⁴ Mv ^0.83
c = 0.7

The higher the haze after moist heat treatment, the lower the transparency of the molded sheet. A greater decrease in viscosity-average molecular weight after moist heat treatment indicates that the resin is more susceptible to hydrolysis. The increase in haze before and after moist heat treatment is represented by ΔHaze, with values of ΔHaze 8.0 or less being marked with ○, and values exceeding 8.0 being marked with ×. Furthermore, the decrease in Mv before and after moist heat treatment is represented by ΔMv, with values of Mv 14,000 or higher or ΔMv 2,000 or less being marked with ○, and values of Mv less than 14,000 and ΔMv exceeding 2,000 being marked with ×.

(4) Melt volume flow rate (MVR)
Pellets obtained from each composition of the examples were dried at 120°C for 4 hours in a hot air circulation dryer, and the melt volume flow rate (MVR) was measured in accordance with ISO 1133 using a semi-automatic melt indexer [3A, manufactured by Toyo Seiki Seisakusho Co., Ltd.]. A melt volume flow rate of 80 ^cm³ /10 min or more was marked with ◎, 60 ^cm³ /10 min or more and less than 80 ^cm³ /10 min was marked with ○, and less than 60 ^cm³ /10 min was marked with ×.

[Examples 1-9 and Comparative Examples 1-4]
Components A, B, C, and other components were mixed in a blender in the proportions shown in Table 1, and then melt-kneaded using a vented twin-screw extruder to obtain pellets. The vented twin-screw extruder used was a TEX30α manufactured by Japan Steel Works, Ltd. (full meshing, co-direction rotation, double-thread screw). The extrusion conditions were a discharge rate of 30 kg/h, a screw rotation speed of 270 rpm, a vent vacuum of 1 kPa, and an extrusion temperature of 260°C. The evaluation results are shown in Table 1.

Examples 1-9 all exhibit high transparency, show no yellowing, possess good heat and humidity resistance, and have excellent fluidity. On the other hand, comparative examples 1-2, which do not contain component B, exhibit inferior transparency and fluidity compared to those containing component B. Furthermore, in cases of excessive component B, as in comparative example 3, transparency is impaired, and yellowing and deterioration of heat and humidity resistance are observed. Similarly, in cases where the hydrocarbon group has an unsaturated bond rather than an alkyl group, as in comparative example 4, transparency is impaired, and yellowing and deterioration of heat and humidity resistance are also observed.

The polycarbonate resin composition of the present invention exhibits excellent light-guiding properties, minimal yellowing during molding and degradation under humid and hot environments, and superior fluidity. Therefore, molded articles obtained from this polycarbonate resin composition are extremely useful in various industrial applications, including lighting (including LED lighting), office automation equipment, electrical and electronic equipment, and the automotive industry.

Claims (5)

A polycarbonate resin composition having light -guiding properties, characterized by containing (A) 100 parts by weight of polycarbonate resin (component A) and (B) 0.2 to 1.5 parts by weight of a polyether polymer (component B) having an alkyl group at at least one end having a number average molecular weight of 300 to 3,500 and containing units derived from ethylene glycol . The polycarbonate resin composition having light-guiding properties according to claim 1, wherein component B is at least one polyether polymer selected from the group consisting of polyethers having an alkyl group at at least one terminal represented by the following formula [1] .
(In the formula, m is an integer between 10 and 18, and n is an integer between 5 and 40. ) A polycarbonate resin composition having light-guiding properties according to claim 1, comprising (A) 100 parts by weight of polycarbonate resin (component A) and (C) 0.01 to 0.1 parts by weight of a phosphorus-based compound having a phenyl group (component C). The polycarbonate resin composition having light-guiding properties according to claim 3 , wherein component C is a phosphorus-based compound having three phenyl groups represented by the following formula [4].
A molded article made from a polycarbonate resin composition having the light-guiding performance described in claim 1.