JP7656436B2 - Transparent antibacterial polycarbonate resin composition and molded article thereof - Google Patents

Description

The present invention relates to a transparent antibacterial polycarbonate resin composition and a molded article thereof. More specifically, the present invention relates to a transparent antibacterial polycarbonate resin composition and a molded article thereof, the transparency and impact resistance of which have been improved by adding a silver-based glass antibacterial agent to a polycarbonate-polydiorganosiloxane copolymer resin.

Polycarbonate resins are generally used in many applications, including machine parts, automobile parts, electrical and electronic parts, and office equipment parts, due to their excellent properties, such as excellent transparency, impact resistance, heat resistance, dimensional stability, and flame retardancy. In recent years, in order to prevent the spread of known and unknown pathogens, as well as from the perspective of hygiene and cleanliness-oriented considerations, there is a demand for materials with antibacterial properties for the exteriors and various parts of products that can be used by an unspecified number of people, such as home appliances such as toilets, home appliances such as refrigerators and air conditioners, medical equipment, ATMs (automated teller machines), POS terminals, mobile phones, and smartphones installed in convenience stores.

As a method for imparting antibacterial properties to polycarbonate resin, a method of adding various phosphorus-based or phenol-based antioxidants, heat stabilizers, and acid-modified olefin waxes to inorganic antibacterial agents (for example, calcium phosphate, zeolite, zirconium phosphate, etc. carrying antibacterial metal ions such as silver, copper, and zinc) has been proposed (Patent Documents 1 to 3), but the antibacterial properties were not sufficient. As a method for improving antibacterial properties, a method of using silver-based and zinc-based antibacterial agents in combination (Patent Document 4) has been proposed, but the various characteristics when added to a polycarbonate resin composition were not sufficient. As a method for imparting antibacterial properties without impairing the characteristics of polycarbonate resin, a method of adding an antibacterial agent containing glass that elutes silver ions (Patent Document 5) and a method of blending a zinc-based glass antibacterial agent and a silver-based zirconium phosphate antibacterial agent in a specific ratio (Patent Document 6) have been proposed, but the former does not sufficiently suppress the decrease in impact resistance and heat resistance, which are generally sacrificed by adding glass components, and the latter is recognized as maintaining impact resistance, but transparency and heat resistance are sacrificed, and were not considered.

Japanese Patent Application Publication No. 6-240125 Japanese Patent Application Publication No. 10-168294 Japanese Patent Application Publication No. 11-323117 JP 2007-217300 A JP 2011-137068 A JP 2017-132913 A

The object of the present invention is to provide a transparent antibacterial polycarbonate resin composition that exhibits antibacterial properties without impairing the inherent characteristics of polycarbonate resin, namely transparency and impact resistance.

As a result of intensive research aimed at solving the above problems, the present inventors discovered that a resin composition in which a silver-based glass antibacterial agent is added to a polycarbonate-polydiorganosiloxane copolymer resin exhibits antibacterial properties while simultaneously achieving both transparency and good impact resistance, and thus completed the present invention. According to the present invention, the above problems are solved by the following configuration.

(Configuration 1)
A transparent antibacterial polycarbonate resin composition comprising 100 parts by weight of (A) a polycarbonate-polydiorganosiloxane copolymer resin (component A-1) or a mixture (component A-1) of component A-1 and a polycarbonate resin other than component A-1 (component A-2) comprising a repeating unit represented by the following general formula [1], and (B) 0.3 to 5 parts by weight of a silver-based glass antibacterial agent (component B) supported on glass so that silver ions are eluted, wherein the haze of a molded article having a thickness of 2 mm and made of the resin composition is less than 50%.

[In formula [1], R ¹ and R ² each independently represent a group selected from the group consisting of a hydrogen atom, a halogen atom, an alkyl group having 1 to 18 carbon atoms, an alkoxy group having 1 to 18 carbon atoms, a cycloalkyl group having 6 to 20 carbon atoms, a cycloalkoxy group having 6 to 20 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an aryl group having 6 to 14 carbon atoms, an aryloxy group having 6 to 14 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, an aralkyloxy group having 7 to 20 carbon atoms, a nitro group, an aldehyde group, a cyano group, and a carboxy group, and when there are a plurality of each, they may be the same or different, e and f each represent an integer of 1 to 4, and W represents a single bond or at least one group selected from the group consisting of groups represented by the following formula [2].]

[In formula [2], R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ , R ¹⁶ , R ¹⁷ and R ¹⁸ each independently represent a group selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, an aryl group having 6 to 14 carbon atoms and an aralkyl group having 7 to 20 carbon atoms; R ¹⁹ and R ²⁰ each independently represents a group selected from the group consisting of a hydrogen atom, a halogen atom, an alkyl group having 1 to 18 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a cycloalkyl group having 6 to 20 carbon atoms, a cycloalkoxy group having 6 to 20 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an aryl group having 6 to 14 carbon atoms, an aryloxy group having 6 to 10 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, an aralkyloxy group having 7 to 20 carbon atoms, a nitro group, an aldehyde group, a cyano group, and a carboxy group, and when there are a plurality of such groups, they may be the same or different, g is an integer from 1 to 10, and h is an integer from 4 to 7.]

(Configuration 2)
The transparent antibacterial polycarbonate resin composition according to the above-mentioned constitution 1, characterized in that the A-1 component is a polycarbonate-polydiorganosiloxane copolymer resin containing a repeating unit represented by the following general formula [3]:

[In formula [3], R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ 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; R ⁹ and R ¹⁰ are each independently a hydrogen atom, a halogen atom, an alkyl group having 1 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms; p is a natural number; q is 0 or a natural number; and p+q is a natural number from 30 to 50. X is a divalent aliphatic group having 2 to 8 carbon atoms.]

(Configuration 3)
3. The transparent antibacterial polycarbonate resin composition according to the above-mentioned constitution 2, wherein R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ in the above-mentioned general formula [3] are methyl groups.

(Configuration 4)
The transparent antibacterial polycarbonate resin composition according to the above-mentioned constitution 2 or 3, characterized in that the repeating unit represented by the above-mentioned general formula [3] is a repeating unit derived from a (2-allylphenol)-terminated polydiorganosiloxane or a (2-methoxy-4-allylphenol)-terminated polydiorganosiloxane.

(Configuration 5)
5. The transparent antibacterial polycarbonate resin composition according to any one of the above structures 1 to 4, characterized in that the content of the A-1 component is 5 to 100 parts by weight per 100 parts by weight of the total of the A-1 component and the A-2 component.

(Configuration 6)
The transparent antibacterial polycarbonate resin composition according to any one of the above structures 2 to 5, characterized in that the content of the polydiorganosiloxane block represented by the above general formula [3] is 0.5 to 20% by weight based on the total weight of the component A.

(Configuration 7)
7. The transparent antibacterial polycarbonate resin composition according to any one of the above configurations 2 to 6, wherein the A-1 component has an aggregate structure in which polydiorganosiloxane domains are dispersed in a polycarbonate resin matrix, and the average size of the polydiorganosiloxane domains is 5 to 15 nm and the normalized dispersion is 25% or less.

(Configuration 8)
8. The transparent antibacterial polycarbonate resin composition according to any one of the above configurations 1 to 7, wherein the average particle size (D50) of component B measured by a laser diffraction/scattering method is 7 to 15 μm.

(Configuration 9)
9. The transparent antibacterial polycarbonate resin composition according to any one of the above structures 1 to 8, characterized in that it contains, relative to 100 parts by weight of Component A, 0.01 to 0.1 parts by weight of (C) a phosphorus-based stabilizer (Component C), 0.1 to 1 parts by weight of (D) a release agent (Component D), and 0 to 1 parts by weight of (E) an ultraviolet absorbing agent (Component E).

(Configuration 10)
A molded article obtained by molding the transparent antibacterial polycarbonate resin composition according to any one of the above items 1 to 9.

The transparent antibacterial polycarbonate resin composition of the present invention can provide molded articles that exhibit antibacterial properties without impairing the inherent characteristics of polycarbonate resin, such as transparency and impact resistance. The composition is useful for applications that can be used by an unspecified number of people, such as plastic parts related to toilets and washstands, the exteriors of tablets, laptops, smartphones, digital cameras, medical monitors, POS, office machines, printers, televisions, and the like, as well as irons, hair dryers, rice cookers, microwave ovens, air conditioners, air purifiers, negative ion generators, various buttons and switches, doorknobs, amusement-related plastic parts, and various vehicle-related plastic parts, and the industrial effects it provides are exceptional.

(Component A)
Component A is a polycarbonate-polydiorganosiloxane copolymer resin (component A-1) or a mixture of component A-1 and a polycarbonate resin (component A-2) other than component A-1 which comprises a repeating unit represented by the following general formula [1]:

(A-1 Component: Polycarbonate-Polydiorganosiloxane Copolymer Resin)
In the present invention, the polycarbonate-polydiorganosiloxane copolymer resin (hereinafter sometimes abbreviated as PC-POS copolymer) is preferably a polycarbonate-polydiorganosiloxane copolymer resin containing a repeating unit represented by formula [3], and more preferably a polycarbonate-polydiorganosiloxane copolymer resin composed of a polycarbonate block represented by formula [1] and a polydiorganosiloxane block represented by formula [3].

<Polycarbonate block represented by formula [1]>
In the present invention, the polycarbonate block is represented by the following formula [1].

[In formula [1], R ¹ and R ² each independently represent a group selected from the group consisting of a hydrogen atom, a halogen atom, an alkyl group having 1 to 18 carbon atoms, an alkoxy group having 1 to 18 carbon atoms, a cycloalkyl group having 6 to 20 carbon atoms, a cycloalkoxy group having 6 to 20 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an aryl group having 6 to 14 carbon atoms, an aryloxy group having 6 to 14 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, an aralkyloxy group having 7 to 20 carbon atoms, a nitro group, an aldehyde group, a cyano group, and a carboxy group, and when there are a plurality of each, they may be the same or different, e and f each represent an integer of 1 to 4, and W represents a single bond or at least one group selected from the group consisting of groups represented by the following formula [2].]

[In formula [2], R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ , R ¹⁶ , R ¹⁷ and R ¹⁸ each independently represent a group selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, an aryl group having 6 to 14 carbon atoms and an aralkyl group having 7 to 20 carbon atoms; R ¹⁹ and R ²⁰ each independently represents a group selected from the group consisting of a hydrogen atom, a halogen atom, an alkyl group having 1 to 18 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a cycloalkyl group having 6 to 20 carbon atoms, a cycloalkoxy group having 6 to 20 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an aryl group having 6 to 14 carbon atoms, an aryloxy group having 6 to 10 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, an aralkyloxy group having 7 to 20 carbon atoms, a nitro group, an aldehyde group, a cyano group, and a carboxy group, and when there are a plurality of such groups, they may be the same or different, g is an integer from 1 to 10, and h is an integer from 4 to 7.]

Examples of halogen atoms include fluorine, chlorine, and bromine atoms. Examples of alkyl groups having 1 to 18 carbon atoms include methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, dodecyl, and tetradecyl groups. An alkyl group having 1 to 6 carbon atoms is preferable. Examples of alkoxy groups having 1 to 18 carbon atoms include methoxy, ethoxy, propoxy, butoxy, pentoxy, hexoxy, and octoxy groups. An alkoxy group having 1 to 6 carbon atoms is preferable. Examples of cycloalkyl groups having 6 to 20 carbon atoms include cyclohexyl and cyclooctyl groups. An cycloalkyl group having 6 to 12 carbon atoms is preferable. Examples of cycloalkoxy groups having 6 to 20 carbon atoms include cyclohexyloxy and cyclooctyloxy groups. An cycloalkyl group having 6 to 12 carbon atoms is preferable. Examples of alkenyl groups having 2 to 10 carbon atoms include methenyl, ethenyl, propenyl, butenyl, and pentenyl groups. Alkenyl groups having 2 to 6 carbon atoms are preferred. Examples of aryl groups having 6 to 14 carbon atoms include phenyl and naphthyl groups. Examples of aryloxy groups having 6 to 14 carbon atoms include phenyloxy and naphthyloxy groups. Examples of aralkyl groups having 7 to 20 carbon atoms include benzyl and phenylethyl groups. Examples of aralkyloxy groups having 7 to 20 carbon atoms include benzyloxy and phenylethyloxy groups.

Examples of alkyl groups having 1 to 18 carbon atoms include methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, and dodecyl groups. Preferred are alkyl groups having 1 to 6 carbon atoms. Examples of aryl groups having 6 to 14 carbon atoms include phenyl and naphthyl groups. These may be substituted. Examples of substituents include alkyl groups having 1 to 6 carbon atoms, such as methyl, ethyl, propyl, and butyl groups. Examples of aralkyl groups having 7 to 20 carbon atoms include benzyl and phenylethyl groups.

g is preferably an integer from 1 to 6. h is preferably an integer from 4 to 5.

The polycarbonate block represented by formula [1] is preferably derived from 2,2-bis(4-hydroxyphenyl)propane.

The length of the polycarbonate block is the average number of repeating units of formula [1], and is preferably 10 to 100, more preferably 30 to 100, and even more preferably 50 to 70.

The content of the polycarbonate block represented by formula [1] is preferably 50 to 99.9% by weight, more preferably 80 to 99.5% by weight, and even more preferably 90 to 99.0% by weight, based on the total weight of the PC-POS copolymer.

<Polydiorganosiloxane block represented by formula [3]>
In the present invention, the polydiorganosiloxane block is represented by the following formula [3].

[In formula [3], R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ 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; R ⁹ and R ¹⁰ are each independently a hydrogen atom, a halogen atom, an alkyl group having 1 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms; p is a natural number; q is 0 or a natural number; and p+q is a natural number from 30 to 50. X is a divalent aliphatic group having 2 to 8 carbon atoms.]

Examples of the alkyl group having 1 to 12 carbon atoms include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, and a dodecyl group. An alkyl group having 1 to 6 carbon atoms is preferable. Examples of the substituted or unsubstituted aryl group having 6 to 12 carbon atoms include a phenyl group and a naphthyl group. Examples of the substituent include an alkyl group having 1 to 12 carbon atoms, such as a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, and a hexyl group. It is preferable that R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ , and R ⁸ are a methyl group.

Examples of halogen atoms include fluorine, chlorine, and bromine atoms. Examples of alkyl groups having 1 to 10 carbon atoms include methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, and dodecyl groups. Preferred are alkyl groups having 1 to 6 carbon atoms. Examples of alkoxy groups having 1 to 10 carbon atoms include methoxy, ethoxy, propoxy, butoxy, pentoxy, hexoxy, heptoxy, and octoxy groups. Preferred are alkoxy groups having 1 to 6 carbon atoms.

Divalent aliphatic groups include alkylene groups having 2 to 8 carbon atoms. Examples of alkylene groups include ethylene groups, trimethylene groups, and tetramethylene groups.

The polydiorganosiloxane block represented by the above formula [3] is preferably a polydiorganosiloxane block derived from a (2-allylphenol)-terminated polydiorganosiloxane or a (2-methoxy-4-allylphenol)-terminated polydiorganosiloxane. That is, in the above formula [3], it is preferable that X is a trimethylene group and R ⁹ and R ¹⁰ are hydrogen atoms, or that X is a trimethylene group and R ⁹ and R ¹⁰ are methoxy groups.

The content of the polydiorganosiloxane block represented by the above formula [3] is preferably 0.5 to 20.0% by weight, more preferably 1.0 to 18.0% by weight, even more preferably 2.0 to 15.0% by weight, and particularly preferably 3.0 to 10.0% by weight, based on the total weight of the PC-POS copolymer. If it is below the lower limit of this preferred range, not only will the desired refractive index of the PC-POS copolymer, which is important for expressing the transparency of the resin composition in the present invention, not be obtained, but the domain formation described below will be insufficient, and the improvement effect of impact resistance (particularly in a low-temperature environment such as -30°C) may not be fully expressed. On the other hand, if it exceeds the upper limit of this preferred range, major problems in terms of production may occur, such as polymerization reaction failure due to deterioration of the emulsion state or difficulty in granulation due to a too low glass transition temperature, or the transparency and heat resistance of the PC-POS copolymer may decrease.

The viscosity average molecular weight of component A-1 is preferably 11,000 to 30,000, more preferably 15,000 to 27,000, and even more preferably 18,000 to 25,000. Below the lower limit of this preferred range, it may be difficult to obtain practical mechanical strength in many fields, and the difference in melt viscosity with the polycarbonate resin (component A-2) other than component A-1 to be mixed may become large, resulting in poor melt-kneadability. On the other hand, above the upper limit of this preferred range, the melt viscosity is high and generally requires a high molding processing temperature, which may lead to problems such as thermal degradation of the resin and reduced productivity due to poor separation in the water washing step during production.

p + q is 30 to 50, and more preferably 30 to 45. If it is below the lower limit of this preferred range, a sufficient improvement in impact resistance cannot be obtained, while if it exceeds the upper limit of this preferred range, excellent transparency is not achieved.

(A-2 component: polycarbonate resin other than A-1 component)
The polycarbonate resin (A-2 component) other than the A-1 component in the present invention is derived from a dihydric phenol represented by the following general formula [4].

(In the above general formula [4], R ¹ , R ² , e, f and W are the same as those in formula [1].)

[In formula [2], R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ , R ¹⁶ , R ¹⁷ and R ¹⁸ each independently represent a group selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, an aryl group having 6 to 14 carbon atoms and an aralkyl group having 7 to 20 carbon atoms; R ¹⁹ and R ²⁰ each independently represents a group selected from the group consisting of a hydrogen atom, a halogen atom, an alkyl group having 1 to 18 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a cycloalkyl group having 6 to 20 carbon atoms, a cycloalkoxy group having 6 to 20 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an aryl group having 6 to 14 carbon atoms, an aryloxy group having 6 to 10 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, an aralkyloxy group having 7 to 20 carbon atoms, a nitro group, an aldehyde group, a cyano group, and a carboxy group, and when there are a plurality of such groups, they may be the same or different, g is an integer from 1 to 10, and h is an integer from 4 to 7.]

Examples of the dihydric phenol 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, 2,2-bis(3-t-butyl-4-hydroxy 2,2-bis(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)diphenylmethane, 4,4'-Dihydroxydiphenyl)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'-dihydro Examples of such compounds include 4,4'-dihydroxy-3,3'-diphenyldiphenyl sulfoxide, 4,4'-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, and 1,3-bis(4-hydroxyphenyl)-5,7-dimethyladamantane.

Among these, 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, 9,9-bis(4-hydroxy-3-methylphenyl)fluorene, 1,3-bis{2-(4-hydroxyphenyl)propyl}benzene, and 1,4-bis{2-(4-hydroxyphenyl)propyl}benzene are preferred, and 2,2-bis(4-hydroxyphenyl)propane, 1,1-bis(4-hydroxyphenyl)cyclohexane (BPZ), 4,4'-sulfonyldiphenol, and 9,9-bis(4-hydroxy-3-methylphenyl)fluorene are particularly preferred. Among these, 2,2-bis(4-hydroxyphenyl)propane is the most suitable, as it gives rise to polycarbonate resins that are excellent in transparency, strength, and durability. These may be used alone or in combination of two or more.

The A component in the present invention is a polycarbonate-polydiorganosiloxane copolymer resin (A-1 component) or a mixture of A-1 component and a polycarbonate resin (A-2 component) other than A-1 component, which comprises a repeating unit represented by the above general formula [1]. The content of A-1 component in 100 parts by weight of the A component is preferably 5 to 100 parts by weight, more preferably 20 to 100 parts by weight, and even more preferably 50 to 100 parts by weight. If the A-1 component is less than this preferred range, sufficient impact resistance may not be exhibited.

In the present invention, the content of the polydiorganosiloxane block represented by the above general formula [3] is preferably 0.5 to 20.0% by weight, more preferably 0.8 to 15.0% by weight, and even more preferably 1.0 to 9.0% by weight, based on the total weight of component A. If the content is below the lower limit of this preferred range, transparency and impact resistance may not be fully exhibited, and if the content exceeds the upper limit of this preferred range, impact resistance, mechanical properties, and heat resistance may decrease.

The viscosity average molecular weight of component A is preferably 11,000 to 30,000, and more preferably 13,000 to 25,000. Below the lower limit of this preferred range, it may be difficult to obtain practical mechanical strength in many fields, and above the upper limit of this preferred range, the melt viscosity increases and requires a high molding processing temperature, which may lead to discoloration due to thermal degradation and a decrease in mechanical properties.

(Domain size of polydiorganosiloxane)
The PC-POS copolymer in the present invention has an aggregate structure in which polydiorganosiloxane domains are dispersed in a polycarbonate polymer matrix.

In the present invention, the polydiorganosiloxane domain refers to a domain that is mainly composed of polydiorganosiloxane dispersed in a polycarbonate matrix, and may contain other components. As described above, the polydiorganosiloxane domain does not necessarily consist of a single component because its structure is formed by phase separation from the polycarbonate matrix.

In the polycarbonate-polydiorganosiloxane copolymer resin (component A-1), the average size of the polydiorganosiloxane domains is preferably 5 to 15 nm, and more preferably 7 to 12 nm. If it is less than the lower limit of this preferred range, transparency, impact resistance, and flame retardancy may not be fully exhibited, and if it exceeds the upper limit of this preferred range, the desired transparency may not be achieved.

Furthermore, even if the average size of the polydiorganosiloxane domains is within the preferred range, good and stable transparency may not be achieved if the normalized variance exceeds 25%. The normalized variance of such polydiorganosiloxane domain sizes is more preferably 23% or less, and even more preferably 20% or less. The lower limit of such normalized variance is preferably 7% or more in practical terms, and more preferably 10% or more. By having such a preferred average domain size and normalized variance, a polycarbonate-polydiorganosiloxane copolymer resin and molded articles thereof that are excellent in both transparency, impact resistance, and flame retardancy may be provided.

The average domain size and normalized dispersion of the polydiorganosiloxane domains of the polycarbonate-polydiorganosiloxane copolymer resin molded product in the present invention are evaluated by small angle X-ray scattering (SAXS). Small angle X-ray scattering is a method for measuring diffuse scattering and diffraction occurring in a small angle region where the scattering angle (2θ) is less than 10°. In this small angle X-ray scattering method, if there are regions in a substance with different electron densities of about 1 to 100 nm in size, the diffuse scattering of X-rays is measured based on the electron density difference. The particle size of the measurement object is determined based on the scattering angle and scattering intensity. In the case of a polycarbonate-polydiorganosiloxane copolymer resin having an aggregate structure in which polydiorganosiloxane domains are dispersed in a polycarbonate polymer matrix, the difference in electron density between the polycarbonate matrix and the polydiorganosiloxane domains causes diffuse scattering of X-rays. The scattering intensity I at each scattering angle (2θ) in the range of scattering angles (2θ) less than 10° is measured to measure a small-angle X-ray scattering profile, and assuming that the polydiorganosiloxane domains are spherical domains and that there is variation in particle size distribution, a simulation is performed using commercially available analysis software from a tentative particle size and a tentative particle size distribution model to determine the average size and particle size distribution (normalized variance) of the polydiorganosiloxane domains. The small-angle X-ray scattering method allows the average size and particle size distribution of the polydiorganosiloxane domains dispersed in a polycarbonate polymer matrix to be measured accurately, easily, and with good reproducibility, which cannot be accurately measured by observation using a transmission electron microscope.

The average domain size means the number average of the individual domain sizes. The normalized variance means a parameter that normalizes the spread of the particle size distribution by the average size. Specifically, it is the value that normalizes the variance of the polydiorganosiloxane domain size by the average domain size, and is expressed by the following formula (1).

In the above formula (1), δ is the standard deviation of the polydiorganosiloxane domain size, and D _av is the average domain size.

The terms "average domain size" and "normalized variance" used in connection with the present invention refer to measurements obtained by measuring a molded product having a thickness of 1.0 mm formed by injection molding using the above-mentioned small angle X-ray scattering method. Note that the analysis was performed using an isolated particle model that does not take into account interparticle interactions (interparticle interference).

(Polydiorganosiloxane)
In the present invention, a polydiorganosiloxane having a specific average chain length and represented by the following general formula [5], hydroxyaryl-terminated polydiorganosiloxane (II), is used as a raw material.

[In formula [5], R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ each independently represent 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; R ⁹ and R ¹⁰ each independently represent a hydrogen atom, a halogen atom, an alkyl group having 1 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms; p is a natural number; q is 0 or a natural number; and p+q is a natural number of 30 to 50; and X is a divalent aliphatic group having 2 to 8 carbon atoms.]

The average chain length p+q is 30 to 50, preferably 30 to 45. Below the lower limit of this preferred range, sufficient impact resistance improvement effect cannot be obtained, and above the upper limit of this preferred range, excellent transparency may not be achieved.

As the hydroxyaryl-terminated polydiorganosiloxane (II) represented by the general formula [5], for example, the following compounds are preferably used.

Hydroxyaryl-terminated polydiorganosiloxane (II) is a phenol having an olefinically unsaturated carbon-carbon bond, and is easily produced by subjecting vinylphenol, 2-allylphenol, isopropenylphenol, or 2-methoxy-4-allylphenol to a hydrosilylation reaction at the end of a polysiloxane chain having a predetermined degree of polymerization. Among these, (2-allylphenol)-terminated polydiorganosiloxane and (2-methoxy-4-allylphenol)-terminated polydiorganosiloxane are preferred, and (2-allylphenol)-terminated polydimethylsiloxane and (2-methoxy-4-allylphenol)-terminated polydimethylsiloxane are particularly preferred.

In the present invention, only one type of hydroxyaryl-terminated polydiorganosiloxane (II) may be used, or two or more types may be used.

In addition, other comonomers than the dihydric phenol (I) and hydroxyaryl-terminated polydiorganosiloxane (II) may be used in an amount of 10% by weight or less based on the total weight of the copolymer, provided that the use of these comonomers does not interfere with the production process of the present invention.

<Method for producing polycarbonate-polydiorganosiloxane copolymer resin>
In the case of the PC-POS copolymer of the present invention, a mixed solution containing an oligomer having a terminal chloroformate group is prepared in advance by reacting a dihydric phenol (I) with a carbonate ester-forming compound in a mixed solution of a water-insoluble organic solvent and an aqueous alkali solution.

When producing an oligomer of dihydric phenol (I), the entire amount of dihydric phenol (I) used in the method of the present invention may be converted into an oligomer at once, or a part of it may be added as a post-added monomer as a reaction raw material to the interfacial polycondensation reaction in the latter stage. A post-added monomer is added to speed up the polycondensation reaction in the latter stage, and there is no need to add it if it is not necessary.

The method for this oligomer formation reaction is not particularly limited, but it is usually preferable to carry out the reaction in a solvent in the presence of an acid binder.

The proportion of the carbonate ester-forming compound used may be adjusted appropriately, taking into consideration the stoichiometric ratio (equivalents) of the reaction. When using a gaseous carbonate ester-forming compound such as phosgene, it is preferable to blow this into the reaction system.

As the acid binder, for example, an alkali metal hydroxide such as sodium hydroxide or potassium hydroxide, an alkali metal carbonate such as sodium carbonate or potassium carbonate, an organic base such as pyridine, or a mixture of these may be used. Similarly to the above, the proportion of the acid binder used may be appropriately determined taking into account the stoichiometric ratio (equivalents) of the reaction. Specifically, it is preferable to use 2 equivalents or a slightly excess amount of the acid binder relative to the number of moles of the dihydric phenol (I) used to form the oligomer (usually 1 mole corresponds to 2 equivalents).

As the solvent, a solvent inert to various reactions, such as those used in the production of known polycarbonates, may be used alone or as a mixture of solvents. Representative examples include hydrocarbon solvents such as xylene, and halogenated hydrocarbon solvents such as methylene chloride and chlorobenzene. In particular, halogenated hydrocarbon solvents such as methylene chloride are preferably used.

There are no particular restrictions on the reaction pressure for oligomer production, and it may be normal pressure, elevated pressure, or reduced pressure, but it is usually advantageous to carry out the reaction under normal pressure. The reaction temperature is selected from the range of -20 to 50°C, and since heat is generated during polymerization in many cases, it is desirable to cool the reaction with water or ice. The reaction time depends on other conditions and cannot be specified in general, but it is usually carried out for 0.2 to 10 hours.

The pH range for the oligomer formation reaction is similar to known interfacial reaction conditions, and the pH is always adjusted to 10 or higher.

In this way, the present invention obtains a mixed solution containing an oligomer of dihydric phenol (I) having terminal chloroformate groups, and then adds the hydroxyaryl-terminated polydiorganosiloxane (II) to the dihydric phenol (I) while stirring the mixed solution, and then the hydroxyaryl-terminated polydiorganosiloxane (II) and the oligomer are subjected to interfacial polycondensation to obtain a polycarbonate-polydiorganosiloxane copolymer resin.

In carrying out the interfacial polycondensation reaction, an acid binder may be appropriately added in consideration of the stoichiometric ratio (equivalents) of the reaction. Examples of acid binders include alkali metal hydroxides such as sodium hydroxide and potassium hydroxide, alkali metal carbonates such as sodium carbonate and potassium carbonate, organic bases such as pyridine, and mixtures thereof. Specifically, when the hydroxyaryl-terminated polydiorganosiloxane (II) used or a portion of the dihydric phenol (I) as described above is added to this reaction stage as a post-added monomer, it is preferable to use 2 equivalents or an excess amount of alkali relative to the total moles of the post-added dihydric phenol (I) and hydroxyaryl-terminated polydiorganosiloxane (II) (usually 1 mole corresponds to 2 equivalents).

The polycondensation by interfacial polycondensation reaction between the oligomer of dihydric phenol (I) and the hydroxyaryl-terminated polydiorganosiloxane (II) is carried out by vigorously stirring the above mixture.

In such polymerization reactions, a terminal terminator or a molecular weight regulator is usually used. Examples of terminal terminators include compounds having a monovalent phenolic hydroxyl group, such as ordinary phenol, p-tert-butylphenol, p-cumylphenol, tribromophenol, and the like, as well as long-chain alkylphenols, aliphatic carboxylic acid chlorides, aliphatic carboxylic acids, hydroxybenzoic acid alkyl esters, hydroxyphenyl alkyl acid esters, and alkyl ether phenols. The amount of such agents used is preferably 100 to 0.5 mol, and more preferably 50 to 2 mol, per 100 mol of all dihydric phenol compounds used. Naturally, two or more types of the above terminal terminators can be used in combination.

To accelerate the polycondensation reaction, a catalyst such as a tertiary amine like triethylamine or a quaternary ammonium salt may be added.

The reaction time of such a polymerization reaction needs to be relatively long in order to reduce the amount of unreacted polydiorganosiloxane components, and is preferably 30 minutes or more, and more preferably 50 minutes or more. On the other hand, since polymer precipitation may occur due to stirring of the reaction solution for a long period of time, the reaction time of such a polymerization reaction is preferably 180 minutes or less, and more preferably 90 minutes or less.

If desired, small amounts of antioxidants such as sodium sulfite or hydrosulfide may be added.

In addition, the polycarbonate resin composition of the present invention can be made into a branched polycarbonate by using a branching agent in combination with the above-mentioned dihydric phenol compound. Examples of trifunctional or higher polyfunctional aromatic compounds used in such branched polycarbonate resins include phloroglucine, phloroglucide, 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, 2,6-bis(2-hydroxy-5-methylbenzyl)-4-methylphenol, 4-{4-[1,1-bis(4- Examples include trisphenols such as {4-hydroxyphenyl)ethyl]benzene}-α,α-dimethylbenzylphenol, tetra(4-hydroxyphenyl)methane, bis(2,4-dihydroxyphenyl)ketone, 1,4-bis(4,4-dihydroxytriphenylmethyl)benzene, trimellitic acid, pyromellitic acid, benzophenonetetracarboxylic acid, and acid chlorides thereof, among which 1,1,1-tris(4-hydroxyphenyl)ethane and 1,1,1-tris(3,5-dimethyl-4-hydroxyphenyl)ethane are preferred, with 1,1,1-tris(4-hydroxyphenyl)ethane being particularly preferred.

The reaction pressure can be reduced, normal, or increased, but is usually suitable for carrying out the reaction at normal pressure or at the reaction system's own pressure. The reaction temperature is selected from the range of -20 to 50°C, and since the polymerization often generates heat, it is desirable to cool the reaction with water or ice. The reaction time varies depending on other conditions such as the reaction temperature and cannot be specified in general, but is usually carried out for 0.5 to 10 hours.

In some cases, the obtained polycarbonate copolymer resin can be appropriately subjected to a physical treatment (mixing, fractionation, etc.) and/or a chemical treatment (polymer reaction, crosslinking treatment, partial decomposition treatment, etc.) to obtain a polycarbonate copolymer resin having a desired reduced viscosity [η _SP /c].

The resulting reaction product (crude product) can be subjected to various post-treatments, such as known separation and purification methods, to recover a polycarbonate-polydiorganosiloxane copolymer resin of the desired purity (degree of purification).

(Component B: Silver-based glass antibacterial agent supported on glass so that silver ions are eluted)
The resin composition of the present invention contains, as component B, a silver-based glass antibacterial agent supported on glass so that silver ions are eluted. In particular, it is preferable that the composition contains silver oxide, phosphorus oxide, and zinc oxide, has excellent transparency as a composition, and has a polyhedral shape. Excellent transparency is essential for maintaining the transparency of the resin composition when mixed and dispersed in a transparent resin, and when the shape is polyhedral, it is easy to disperse uniformly in the resin and is easy to be oriented in a certain direction during molding, which suppresses light scattering, making it suitable for expressing good transparency of the resin composition.

Such a silver-based glass antibacterial agent preferably contains 0.2 to 5 wt % Ag ₂ O, 50 to 55 wt % P ₂ O ₅ , 40 to 50 wt % ZnO, and 0.1 to 15 wt % B ₂ O ₃ , and more preferably contains 0.1 to 15 wt % CaO relative to the total amount, and the weight ratio of CaO to ZnO (ZnO/CaO) is within the range of 1.1 to 15. When the contents of these components are within the above-mentioned ranges, a silver-based glass antibacterial agent that is excellent in transparency and mechanical properties and stably releases silver ions can be obtained, which is suitable as a component constituting the transparent antibacterial resin composition of the present invention.

Other factors that affect the transparency of the resin composition due to the inclusion of a silver-based glass antibacterial agent include the average particle size (D50) and the refractive index (the difference in the refractive index with the resin matrix). The average particle size (D50) of such a silver-based glass antibacterial agent measured by a laser diffraction/scattering method is preferably 1 to 30 μm, more preferably 3 to 20 μm, and even more preferably 7 to 15 μm. If the average particle size (D50) is less than 1 μm, the expression efficiency on the surface of the molded product may decrease, making it difficult to express antibacterial properties, making it necessary to increase the content, or light scattering may occur easily, leading to a decrease in transparency. On the other hand, if the average particle size (D50) exceeds 30 μm, the surface of the molded product may become rough, causing a deterioration in appearance, or the impact resistance may decrease. In addition, the smaller the difference in the refractive index of such a silver-based glass antibacterial agent with the resin matrix, the more the transparency of the resin composition improves, so the difference in the refractive index is most preferably 0, but due to the characteristics of the refractive index inherent to the substance, such as the Abbe number and anisotropy, it is practically difficult to achieve this. Therefore, the refractive index difference is preferably 0.1 or less, more preferably 0.05 or less, and even more preferably 0.03 or less. An example of the silver-based glass antibacterial agent of the present invention is Zeomic KM10D (product name) manufactured by Sinanen Zeomic Co., Ltd., which is readily available as a commercial product.

The content of component B is 0.3 to 5 parts by weight, preferably 0.3 to 3 parts by weight, and more preferably 0.3 to 1 part by weight, per 100 parts by weight of component A. If the content of component B is less than 0.3 parts by weight, antibacterial properties will not be expressed, and if it exceeds 5 parts by weight, transparency will be impaired and impact resistance will decrease significantly.

(Component C: phosphorus-based stabilizer)
The resin composition of the present invention may contain a phosphorus-based stabilizer as component C to the extent that it does not promote hydrolysis. Such a phosphorus-based stabilizer improves the thermal stability during production or molding, and improves mechanical properties, color, and molding stability. Examples of phosphorus-based stabilizers include phosphorous acid, phosphoric acid, phosphonous acid, phosphonic acid, and their esters, as well as tertiary phosphines.

Specific examples of phosphite compounds include triphenyl phosphite, tris(nonylphenyl)phosphite, tridecyl phosphite, trioctyl phosphite, trioctadecyl phosphite, didecyl monophenyl phosphite, dioctyl monophenyl phosphite, diisopropyl monophenyl phosphite, monobutyl diphenyl phosphite, monodecyl diphenyl phosphite, monooctyl diphenyl phosphite, 2,2-methylenebis(4,6-di-tert-butylphenyl)octyl phosphite, tris(diethylphenyl)phosphite, tris(di-iso-propylphenyl)phosphite, and tris(di-n-butylphenyl)phosphite. , tris(2,4-di-tert-butylphenyl)phosphite, tris(2,6-di-tert-butylphenyl)phosphite, distearyl pentaerythritol diphosphite, bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphite, bis(2,6-di-tert-butyl-4-methylphenyl)pentaerythritol diphosphite, bis(2,6-di-tert-butyl-4-ethylphenyl)pentaerythritol diphosphite, phenyl bisphenol A pentaerythritol diphosphite, bis(nonylphenyl)pentaerythritol diphosphite, dicyclohexyl pentaerythritol diphosphite, etc.

Furthermore, other phosphite compounds that react with dihydric phenols to form a cyclic structure 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, 2,2'-ethylidenebis(4-methyl-6-tert-butylphenyl)(2-tert-butyl-4-methylphenyl)phosphite, etc. can be mentioned.

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, diisopropyl phosphate, etc. Preferred are triphenyl phosphate and trimethyl phosphate.

Examples of the phosphonite compound include tetrakis(2,4-di-tert-butylphenyl)-4,4'-biphenylene diphosphonite, tetrakis(2,4-di-tert-butylphenyl)-4,3'-biphenylene diphosphonite, tetrakis(2,4-di-tert-butylphenyl)-3,3'-biphenylene diphosphonite, tetrakis(2,6-di-tert-butylphenyl)-4,4'-biphenylene diphosphonite, tetrakis(2,6-di-tert-butylphenyl)-4,3'-biphenylene diphosphonite, and tetrakis(2 ,6-di-tert-butylphenyl)-3,3'-biphenylene diphosphonite, bis(2,4-di-tert-butylphenyl)-4-phenyl-phenyl phosphonite, bis(2,4-di-tert-butylphenyl)-3-phenyl-phenyl phosphonite, bis(2,6-di-n-butylphenyl)-3-phenyl-phenyl phosphonite, bis(2,6-di-tert-butylphenyl)-4-phenyl-phenyl phosphonite, bis(2,6-di-tert-butylphenyl)-3-phenyl-phenyl phosphonite, etc. Among these, tetrakis(di-tert-butylphenyl)-biphenylene diphosphonite and bis(di-tert-butylphenyl)-phenyl-phenyl phosphonite are preferred, and tetrakis(2,4-di-tert-butylphenyl)-biphenylene diphosphonite and bis(2,4-di-tert-butylphenyl)-phenyl-phenyl phosphonite are more preferred. Such a phosphonite compound can be preferably used in combination with the above-mentioned phosphite compound having an aryl group substituted with two or more alkyl groups.

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

Examples of tertiary phosphines include triethylphosphine, tripropylphosphine, tributylphosphine, trioctylphosphine, triamylphosphine, dimethylphenylphosphine, dibutylphenylphosphine, diphenylmethylphosphine, diphenyloctylphosphine, triphenylphosphine, tri-p-tolylphosphine, trinaphthylphosphine, and diphenylbenzylphosphine. A particularly preferred tertiary phosphine is triphenylphosphine.

The phosphorus-based stabilizers may be used alone or in combination with two or more other types. Among the above phosphorus-based stabilizers, it is preferable to use them in combination with phosphite compounds and phosphonite compounds.

The content of component C is preferably 0.001 to 0.5 parts by weight, more preferably 0.005 to 0.3 parts by weight, and even more preferably 0.01 to 0.1 parts by weight, per 100 parts by weight of component A.

(Component D: Release agent)
The resin composition of the present invention may contain a mold release agent as component D in order to improve mold releasability during molding and reduce distortion of molded products, within the scope of the present invention.

As such a release agent, known ones can be used. For example, saturated fatty acid esters, unsaturated fatty acid esters, polyolefin waxes (polyethylene wax, 1-alkene polymers, etc. Those modified with functional group-containing compounds such as acid modification can also be used), silicone compounds (silicone oils, organosiloxanes, etc.), fluorine compounds (fluorine oils such as polyfluoroalkyl ethers), paraffin wax, beeswax, etc. Among them, fatty acid esters are preferred as release agents.

Such fatty acid esters are esters of aliphatic alcohols and aliphatic carboxylic acids. Such aliphatic alcohols may be monohydric alcohols or polyhydric alcohols having dihydric or higher valences, and the number of carbon atoms is preferably in the range of 3 to 32, and more preferably in the range of 5 to 30. Examples of such monohydric alcohols include dodecanol, tetradecanol, hexadecanol, octadecanol, eicosanol, tetracosanol, ceryl alcohol, and triacontanol. Examples of such polyhydric alcohols include pentaerythritol, dipentaerythritol, tripentaerythritol, polyglycerol (triglycerol to hexaglycerol), ditrimethylolpropane, xylitol, sorbitol, and mannitol. Polyhydric alcohols are more preferred in the fatty acid esters of the present invention.

On the other hand, the aliphatic carboxylic acid preferably has 3 to 32 carbon atoms, and particularly preferably has 10 to 22 carbon atoms. Examples of the aliphatic carboxylic acid include saturated aliphatic carboxylic acids such as decanoic acid, undecanoic acid, dodecanoic acid, tridecanoic acid, tetradecanoic acid, pentadecanoic acid, hexadecanoic acid (palmitic acid), heptadecanoic acid, octadecanoic acid (stearic acid), nonadecanoic acid, behenic acid, icosanoic acid, and docosanoic acid, and unsaturated aliphatic carboxylic acids such as palmitoleic acid, oleic acid, linoleic acid, linolenic acid, eicosenoic acid, eicosapentaenoic acid, and cetoleic acid. Among the above, the aliphatic carboxylic acid is preferably one having 14 to 20 carbon atoms. Among them, saturated aliphatic carboxylic acids are more preferable. In particular, stearic acid and palmitic acid are even more preferable.

The above-mentioned aliphatic carboxylic acids such as stearic acid and palmitic acid are usually produced from natural oils and fats such as animal oils and fats such as beef tallow and lard, and vegetable oils and fats such as palm oil and sunflower oil, and therefore these aliphatic carboxylic acids are usually mixtures containing other carboxylic acid components with different numbers of carbon atoms. Therefore, in the production of the fatty acid ester of the present invention, aliphatic carboxylic acids produced from such natural oils and fats and in the form of a mixture containing other carboxylic acid components, particularly stearic acid and palmitic acid, are preferably used.

The fatty acid ester may be either a partial ester or a full ester (full ester). However, partial esters usually have a high hydroxyl value and tend to induce decomposition of the resin at high temperatures, so full esters are more preferable. The acid value of such fatty acid esters is preferably 20 or less, more preferably 4 to 20, and even more preferably 4 to 12, from the viewpoint of thermal stability. The acid value can be substantially 0. In addition, the hydroxyl value of such fatty acid esters is preferably 0.1 to 30, and the iodine value of such fatty acid esters is preferably 10 or less. The iodine value can be substantially 0. These properties can be determined by the method specified in JIS K 0070.

The above release agents may be used alone or in combination of two or more.

The content of component D is preferably 0.01 to 2 parts by weight, more preferably 0.05 to 1.5 parts by weight, and even more preferably 0.1 to 1 part by weight, per 100 parts by weight of component A.

(Component E: UV absorber)
The resin composition of the present invention may contain an ultraviolet absorber as component E for the purpose of imparting light resistance. Examples of ultraviolet absorbers include benzophenone-based ultraviolet absorbers, cyclic iminoester-based ultraviolet absorbers, cyanoacrylate-based ultraviolet absorbers, benzotriazole-based ultraviolet absorbers, and triazine-based ultraviolet absorbers. Among these, benzotriazole-based ultraviolet absorbers and triazine-based ultraviolet absorbers are preferred.

Benzotriazole-based UV absorbers include 2-(2-hydroxy-5-methylphenyl)benzotriazole, 2-(2-hydroxy-5-tert-octylphenyl)benzotriazole, 2-(2-hydroxy-3,5-dicumylphenyl)phenylbenzotriazole, 2-(2-hydroxy-3-tert-butyl-5-methylphenyl)-5-chlorobenzotriazole, 2,2'-methylenebis[4-(1,1,3,3-tetramethylbutyl)-6-(2H-benzotriazol-2-yl)phenol], 2-(2-hydroxy-3,5-di-tert-butylphenyl)benzotriazole, 2-(2-hydroxy-3,5-di-tert-butylphenyl)benzotriazole, Examples of such benzotriazoles include 2-(2-hydroxy-3,5-di-tert-amylphenyl)benzotriazole, 2-(2-hydroxy-5-tert-octylphenyl)benzotriazole, 2-(2-hydroxy-5-tert-butylphenyl)benzotriazole, 2-(2-hydroxy-4-octoxyphenyl)benzotriazole, 2,2'-methylenebis(4-cumyl-6-benzotriazolephenyl), 2,2'-p-phenylenebis(1,3-benzoxazin-4-one), and 2-[2-hydroxy-3-(3,4,5,6-tetrahydrophthalimidomethyl)-5-methylphenyl]benzotriazole. Other examples include polymers having a 2-hydroxyphenyl-2H-benzotriazole skeleton, such as a copolymer of 2-(2'-hydroxy-5-methacryloxyethylphenyl)-2H-benzotriazole and a vinyl monomer copolymerizable with the monomer, and a copolymer of 2-(2'-hydroxy-5-acryloxyethylphenyl)-2H-benzotriazole and a vinyl monomer copolymerizable with the monomer.

Suitable examples of triazine-based UV absorbers include hydroxyphenyl triazine-based compounds such as 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-hexyloxyphenol, 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-methyloxyphenol, 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-ethyloxyphenol, 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-propyloxyphenol, and 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-butyloxyphenol. Further examples include compounds in which the phenyl group of the hydroxyphenyl triazine-based compounds listed above is a 2,4-dimethylphenyl group, such as 2-(4,6-bis(2,4-dimethylphenyl)-1,3,5-triazin-2-yl)-5-hexyloxyphenol.

The above UV absorbers may be used alone or in a mixture of two or more.

When light resistance is not required and/or when consideration is given to suppressing deterioration of the mechanical properties (especially impact resistance, etc.) of the resin composition, the content of component E is preferably substantially 0 parts by weight. However, since light resistance is required in many applications, when light resistance is to be imparted, the content of component E is preferably 1 part by weight or less, more preferably 0.5 parts by weight or less, and even more preferably 0.3 parts by weight or less, per 100 parts by weight of component A. When the content of component E exceeds 1 part by weight, not only will the mechanical properties of the resin composition decrease significantly as described above, but the resin composition may also become discolored due to light absorption by the ultraviolet absorber and lose transparency.

(Other additives)
The resin composition of the present invention may contain various known additives depending on the application and necessity, such as flame retardants, fluorine-containing anti-dripping agents, plasticizers, impact modifiers, antistatic agents, light diffusing agents, fillers (titanium oxide, talc, mica, glass fiber, carbon fiber, etc.), fluorescent whitening agents, dyes and pigments, etc.

In particular, polycarbonate resin is known as a resin that is self-extinguishing and has excellent flame retardancy, and because of this characteristic, there are many cases where improved flame retardancy is required. As such, the following additives related to improving flame retardancy are described below: (i) flame retardants and (ii) fluorine-containing drip prevention agents.

(i) Flame Retardant As the flame retardant, various compounds known as flame retardants for thermoplastic resins, particularly aromatic polycarbonate resins, can be used. More preferred are (i) organometallic salt-based flame retardants (e.g., organic sulfonic acid alkali (earth) metal salts, boric acid metal salt-based flame retardants, and stannic acid metal salt-based flame retardants, etc.), (ii) organophosphorus-based flame retardants (e.g., monophosphate compounds, phosphate oligomer compounds, phosphonate oligomer compounds, phosphonitrile oligomer compounds, and phosphonic acid amide compounds, etc.), and (iii) silicone-based flame retardants made of silicone compounds. The incorporation of compounds used as flame retardants not only improves flame retardancy, but also brings about improvements in antistatic properties, fluidity, rigidity, and thermal stability, etc., based on the properties of each compound.

(Organometallic salt flame retardants)
The organic metal salt flame retardant is advantageous in that the heat resistance is almost maintained. The organic metal salt flame retardant most advantageously used in the present invention is an alkali (earth) metal salt of sulfonate. Among them, an alkali (earth) metal salt of a fluorine-substituted organic sulfonic acid is preferred, and an alkali (earth) metal salt of a sulfonic acid having a perfluoroalkyl group is more preferred. Here, the number of carbon atoms in the perfluoroalkyl group is preferably 1 to 18, more preferably 1 to 10, and even more preferably 1 to 8.

The metals constituting the metal ions of the fluorine-substituted organic sulfonic acid alkali (earth) metal salts are alkali metals or alkaline earth metals. Examples of alkali metals include lithium, sodium, potassium, rubidium, and cesium. Examples of alkaline earth metals include beryllium, magnesium, calcium, strontium, and barium. Alkaline metals are more preferred. Therefore, the preferred organic metal salt-based flame retardant is an alkali metal salt of perfluoroalkylsulfonic acid. Among such alkali metals, rubidium and cesium are preferred when a higher transparency is required, but they are not versatile and are difficult to purify, which can result in a disadvantage in terms of cost. On the other hand, although lithium and sodium are advantageous in terms of cost and flame retardancy, they can conversely be disadvantageous in terms of transparency. Taking these into consideration, the alkali metals in the alkali metal salts of perfluoroalkylsulfonic acid can be used differently, but potassium salts of perfluoroalkylsulfonic acid, which have an excellent balance of properties in all respects, are the most preferred. Such potassium salts can also be used in combination with alkali metal salts of perfluoroalkylsulfonic acid made of other alkali metals.

Examples of such alkali metal salts of perfluoroalkylsulfonic acid include potassium trifluoromethanesulfonate, potassium perfluorobutanesulfonate, potassium perfluorohexanesulfonate, potassium perfluorooctane sulfonate, sodium pentafluoroethanesulfonate, sodium perfluorobutanesulfonate, sodium perfluorooctane sulfonate, lithium trifluoromethanesulfonate, lithium perfluorobutanesulfonate, lithium perfluoroheptanesulfonate, cesium trifluoromethanesulfonate, cesium perfluorobutanesulfonate, cesium perfluorooctane sulfonate, cesium perfluorohexanesulfonate, rubidium perfluorobutanesulfonate, and rubidium perfluorohexanesulfonate, and these can be used alone or in combination of two or more. Among these, potassium perfluorobutanesulfonate is particularly preferred.

The above-mentioned organometallic salt flame retardant preferably has a fluoride ion content of 50 ppm or less, more preferably 20 ppm or less, and even more preferably 10 ppm or less, as measured by ion chromatography. The lower the fluoride ion content, the better the flame retardancy and light resistance. The lower limit of the fluoride ion content can be set to substantially 0, but in terms of the balance between the refining process and the effect, a practical value of about 0.2 ppm is preferable. Perfluoroalkylsulfonic acid alkali metal salts having such a fluoride ion content are purified, for example, as follows. Perfluoroalkylsulfonic acid alkali metal salts are dissolved in ion-exchanged water in an amount 2 to 10 times the weight of the metal salt at a temperature in the range of 40 to 90°C (more preferably 60 to 85°C). The alkali metal salt of perfluoroalkylsulfonic acid is produced by neutralizing perfluoroalkylsulfonic acid with an alkali metal carbonate or hydroxide, or by neutralizing perfluoroalkylsulfonyl fluoride with an alkali metal carbonate or hydroxide (preferably the latter method). The ion-exchanged water is particularly preferably water having an electrical resistance of 18 MΩ·cm or more. The liquid in which the metal salt is dissolved is stirred at the above temperature for 0.1 to 3 hours, more preferably for 0.5 to 2.5 hours. The liquid is then cooled to a range of 0 to 40°C, more preferably 10 to 35°C. Crystals are precipitated by cooling. The precipitated crystals are removed by filtration. In this way, a suitable purified alkali metal salt of perfluoroalkylsulfonic acid is produced.

When a fluorine-substituted organic sulfonic acid alkali (earth) metal salt is contained as a flame retardant, the content is preferably 0.01 to 1.0 parts by weight, more preferably 0.05 to 0.8 parts by weight, and even more preferably 0.08 to 0.6 parts by weight, per 100 parts by weight of component A. Within such a suitable range, the effects expected from the inclusion of a fluorine-substituted organic sulfonic acid alkali (earth) metal salt (for example, flame retardancy, antistatic properties, etc.) may be exhibited.

As an organic metal salt-based flame retardant other than the fluorine-substituted alkali (earth) metal salt of an organic sulfonic acid, a metal salt of an organic sulfonic acid that does not contain a fluorine atom is suitable. Examples of such metal salts include alkali metal salts of aliphatic sulfonic acids, alkaline earth metal salts of aliphatic sulfonic acids, alkali metal salts of aromatic sulfonic acids, and alkaline earth metal salts of aromatic sulfonic acids (none of which contain a fluorine atom).

Preferred examples of aliphatic sulfonic acid metal salts include alkylsulfonic acid alkali (earth) metal salts, which can be used alone or in combination of two or more (herein, the term "alkali (earth) metal salt" is used to mean both alkali metal salts and alkaline earth metal salts). Preferred examples of alkanesulfonic acids used in such alkylsulfonic acid alkali (earth) metal salts include methanesulfonic acid, ethanesulfonic acid, propanesulfonic acid, butanesulfonic acid, methylbutanesulfonic acid, hexanesulfonic acid, heptanesulfonic acid, octanesulfonic acid, etc., which can be used alone or in combination of two or more.

The aromatic sulfonic acid used in the aromatic sulfonate alkali (earth) metal salt may be at least one acid selected from the group consisting of monomeric or polymeric aromatic sulfide sulfonic acids, aromatic carboxylic acid and ester sulfonic acids, monomeric or polymeric aromatic ether sulfonic acids, aromatic sulfonate sulfonic acids, monomeric or polymeric aromatic sulfonic acids, monomeric or polymeric aromatic sulfone sulfonic acids, aromatic ketone sulfonic acids, heterocyclic sulfonic acids, aromatic sulfoxide sulfonic acids, and aromatic sulfonic acid condensates with methylene bonds, and these may be used alone or in combination of two or more.

Specific examples of aromatic sulfonic acid alkali (earth) metal salts 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, polysodium poly(2,6-dimethylphenylene oxide) polysulfonate, polysodium poly(1,3-phenylene oxide) polysulfonate, polysodium poly(1,4-phenylene oxide) polysulfonate, polypotassium poly(2,6-diphenylphenylene oxide) polysulfonate, lithium poly(2-fluoro-6-butylphenylene oxide) polysulfonate, potassium sulfonate of benzenesulfonate, sodium ... Examples of suitable sulfonates include thoronium, magnesium benzenesulfonate, dipotassium p-benzenedisulfonate, dipotassium naphthalene-2,6-disulfonate, calcium biphenyl-3,3'-disulfonate, sodium diphenylsulfone-3-sulfonate, potassium diphenylsulfone-3-sulfonate, dipotassium diphenylsulfone-3,3'-disulfonate, dipotassium diphenylsulfone-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, a formalin condensate of sodium naphthalenesulfonate, and a formalin condensate of sodium anthracenesulfonate.

Among the metal salts of organic sulfonic acids that do not contain fluorine atoms, aromatic sulfonic acid alkali (earth) metal salts are preferred, and potassium salts are particularly preferred. When such aromatic sulfonic acid alkali (earth) metal salts are included as flame retardants, the content is preferably 0.01 to 1 part by weight, more preferably 0.05 to 0.8 parts by weight, and even more preferably 0.08 to 0.6 parts by weight, per 100 parts by weight of component A.

(Organophosphorus flame retardant)
As the organic phosphorus flame retardant in the present invention, a phosphate compound, particularly an aryl phosphate compound, is preferred. Such a phosphate compound is effective in improving flame retardancy, and since the phosphate compound has a plasticizing effect, it is advantageous in that it can improve the molding processability of the resin composition of the present invention, although it reduces the heat resistance. As such a phosphate compound, various phosphate compounds known as flame retardants can be used, but more preferably, one or more phosphate compounds represented by the following general formula [6] can be mentioned.

[In formula [6], Y is a dihydric phenol residue derived from a dihydroxy compound selected from the group consisting of hydroquinone, resorcinol, bis(4-hydroxydiphenyl)methane, bisphenol A, 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane, 1,1-bis(4-hydroxyphenyl)cyclohexane, 1,1-bis(4-hydroxyphenyl)-3-methylcyclohexane, dihydroxydiphenyl, dihydroxynaphthalene, bis(4-hydroxyphenyl)sulfone, bis(4-hydroxyphenyl)ketone, and bis(4-hydroxyphenyl)sulfide; g, h, i, and j each independently represent 0 or 1; n represents an integer of 0 to 5, or, in the case of a mixture of phosphate esters having different n numbers, represents the average value thereof; R ²¹ , R ²² , R ²³ , and R Each of ²⁴ is independently a monohydric phenol residue derived from an aryl group selected from the group consisting of phenol, cresol, xylenol, isopropylphenol, butylphenol, and p-cumylphenol.

The phosphate compound of the above formula [6] may be a mixture of compounds having different n numbers. In the case of such a mixture, the average n number is preferably 0.5 to 1.5, more preferably 0.8 to 1.2, even more preferably 0.95 to 1.15, and particularly preferably 1 to 1.14.

Specific examples of suitable dihydric phenols from which Y in the above formula [6] is derived include resorcinol, bisphenol A, and dihydroxydiphenyl, with resorcinol and bisphenol A being particularly preferred.

Preferred specific examples of the monohydric phenol from which R ²¹ , R ²² , R ²³ , and R ²⁴ in the above formula [6] are phenol, cresol, xylenol, and 2,6-dimethylphenol, and among these, phenol and 2,6-dimethylphenol are preferred.

Specific examples of the phosphate compound of the above formula [6] include monophosphate compounds such as triphenyl phosphate and tri(2,6-xylyl)phosphate, as well as phosphate oligomers based on resorcinol bis(di(2,6-xylyl)phosphate), phosphate oligomers based on 4,4-dihydroxydiphenyl bis(diphenyl phosphate), and phosphoric acid ester oligomers based on bisphenol A bis(diphenyl phosphate), and among these, phosphate oligomers based on resorcinol bis(di(2,6-xylyl)phosphate), phosphate oligomers based on 4,4-dihydroxydiphenyl bis(diphenyl phosphate), and phosphoric acid ester oligomers based on bisphenol A bis(diphenyl phosphate) are preferred.

Another example of an organic phosphorus-based flame retardant is phosphazene. Phosphazene contains phosphorus and nitrogen atoms in the molecule, which can impart flame retardancy to the resin composition. There are no particular limitations on the phosphazene, so long as it does not contain halogen atoms and has a phosphazene structure in the molecule. The phosphazene structure here refers to a structure represented by the formula: -P(R)=N- [wherein R is an organic group]. Phosphazene compounds are represented by the general formulas [7] and [8].

(In the above general formulas [7] and [8], R ²⁵ , R ²⁶ , R ²⁷ and R ²⁸ represent hydrogen, a hydroxyl group, an amino group, or an organic group not containing a halogen atom, and n represents an integer of 3 to 10.)

In the above formulas [7] and [8], examples of the organic group not containing a halogen atom represented by R ²⁵ , R ²⁶ , R ²⁷ and R ²⁸ include an alkoxy group, a phenyl group, an amino group and an allyl group.
Among these, a cyclic phenoxyphosphazene represented by the following general formula [9] is preferred.

[In the above general formula [9], n represents an integer of 3 to 10.]

When an organic phosphorus flame retardant is included as the flame retardant, the content is preferably 1 to 20 parts by weight, more preferably 2 to 15 parts by weight, and even more preferably 3 to 10 parts by weight, per 100 parts by weight of component A. Within this preferred range, the effects expected from the inclusion of the organic phosphorus flame retardant (e.g., flame retardancy) may be exhibited without impairing transparency.

(Silicone Compound)
The silicone compound in the present invention is not particularly limited as long as it can obtain the transparency that is the object of the present invention, but it is preferable that the silicone compound has an aromatic group, and more preferably has a viscosity of 300 cSt or less at 25 ° C. If the viscosity is high, the transparency of the molded product may decrease. Furthermore, in order for the silicone compound to efficiently exert the flame retardant effect, the dispersion state during the combustion process is important. Viscosity is an important factor that determines such a dispersion state. This is because, when the silicone compound is too easily volatilized during the combustion process, that is, when the silicone compound has too low a viscosity, the silicone remaining in the system during combustion is thin, making it difficult to form a uniform silicone structure during combustion. From this viewpoint, the viscosity at 25 ° C. is more preferably 10 to 300 cSt, even more preferably 15 to 200 cSt, and particularly preferably 20 to 170 cSt.

The aromatic groups in silicone compounds are bonded to silicone atoms, which contribute to improved compatibility with polycarbonate resins and maintaining transparency, and are also advantageous in forming a carbonized film during combustion, which contributes to the expression of flame retardant effects. If the compound does not have an aromatic group, it tends to be difficult to obtain transparency in molded products and a high level of flame retardancy.

The silicone compound of the present invention is preferably a silicone compound containing a Si-H group. In particular, it is a silicone compound containing a Si-H group and an aromatic group in the molecule,
It is more preferable that the silicone compound be at least one selected from among silicone compounds having (1) an amount of Si—H groups (Si—H amount) of 0.1 to 1.2 mol/100 g, (2) a ratio of aromatic groups represented by the following general formula [10] (aromatic group amount) of 10 to 70% by weight, and (3) an average degree of polymerization of 3 to 150.

(In formula [10], each X independently represents a hydrocarbon group having 1 to 20 carbon atoms, which may have an OH group or a heteroatom-containing functional group. m1 represents an integer from 0 to 5. Furthermore, when m1 is 2 or more in formula [10], each X may be different from the others.)

More preferably, the silicone compound is at least one selected from silicone compounds containing at least one of the structural units represented by the following general formulas [11] and [12] as the Si-H group-containing unit.

(In formula [11] and formula [12], Z ¹ to Z ³ each independently represent a hydrogen atom, a hydrocarbon group having 1 to 20 carbon atoms which may have a heteroatom-containing functional group, or a compound represented by the following general formula [13]. α1 to α3 each independently represent 0 or 1. m2 represents an integer of 0 or 1 or more. Furthermore, in formula [11], when m2 is 2 or more, the repeating unit can be a plurality of repeating units which are different from each other.)

(In formula [13], ^Z4 to ^Z8 each independently represent a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms which may have a heteroatom-containing functional group. α4 to α8 each independently represent 0 or 1. m3 represents an integer of 0 or 1 or more. Furthermore, in formula [14], when m3 is 2 or more, the repeating units can each be a plurality of mutually different repeating units.)

More preferably, when M is a monofunctional siloxane unit, D is a difunctional siloxane unit, and T is a trifunctional siloxane unit, the silicone compound is composed of MD units or MDT units.

Examples of the hydrocarbon group having 1 to 20 carbon atoms, which may have a heteroatom-containing functional group, in Z ¹ to Z ⁸ of the structural units represented by the above formulas [11], [12] and [13] and in X of the above formula [10] include alkyl groups such as methyl, ethyl, propyl, butyl, hexyl and decyl groups, cycloalkyl groups such as cyclohexyl groups, alkenyl groups such as vinyl and allyl groups, aryl groups such as phenyl and tolyl groups, and aralkyl groups, and these groups may further contain various functional groups such as epoxy groups, carboxyl groups, carboxylic anhydride groups, amino groups, and mercapto groups. More preferred are alkyl groups, alkenyl groups or aryl groups having 1 to 8 carbon atoms, and particularly preferred are alkyl groups having 1 to 4 carbon atoms such as methyl, ethyl and propyl groups, vinyl groups or phenyl groups.

In a silicone compound containing at least one of the structural units represented by the formulas [11] and [12] above, when the compound has multiple repeating units of siloxane bonds, the compound can take any of the forms of random copolymerization, block copolymerization, and tapered copolymerization.

In the present invention, for silicone compounds containing Si-H groups, it is preferable that the amount of Si-H in the silicone compound is in the range of 0.1 to 1.2 mol/100g. When the amount of Si-H is in the range of 0.1 to 1.2 mol/100g, the formation of a silicone structure during combustion becomes easier. The amount of Si-H is more preferably 0.1 to 1.0 mol/100g, and even more preferably 0.2 to 0.6 mol/100g. If the amount is less than this preferred range, it becomes difficult to form a silicone structure, and if the amount is more than this preferred range, the thermal stability of the composition decreases. Here, the silicone structure refers to a network structure formed by the reaction between silicone compounds or the reaction between a resin and silicone.

The amount of Si-H groups referred to here means the number of moles of Si-H structures contained in 100 g of a silicone compound, which can be determined by measuring the volume of hydrogen gas generated per unit weight of the silicone compound using an alkali decomposition method. For example, when 122 ml of hydrogen gas is generated per 1 g of a silicone compound at 25° C., the amount of Si-H is calculated to be 0.5 mol/100 g according to the following formula:
122×273/(273+25)÷22400×100≒0.5

The amount of aromatic groups in the silicone compound of the present invention is preferably 10 to 70% by weight, more preferably 15 to 60% by weight, and even more preferably 25 to 55% by weight. If it is less than this preferred range, the silicone compound may be unevenly distributed and poorly dispersed, resulting in poor appearance. On the other hand, if it exceeds this preferred range, the molecular rigidity of the silicone compound itself becomes too high, so it may be unevenly distributed and poorly dispersed, resulting in poor appearance.

The amount of aromatic groups herein refers to the proportion of aromatic groups represented by the above-mentioned formula [10] contained in the silicone compound, and can be calculated by the following formula.
Aromatic group amount = [A/M] x 100 (wt%)
Here, A and M in the above formula respectively represent the following values.
A = the total molecular weight of all aromatic group moieties represented by the general formula [10] contained in one molecule of the silicone compound; M = the molecular weight of the silicone compound

Furthermore, the silicone compound used in the present invention preferably has a refractive index at 25°C of 1.40 to 1.60, more preferably 1.42 to 1.59, and even more preferably 1.44 to 1.59. Within such a preferred range, the silicone compound is finely dispersed in the aromatic polycarbonate, providing a resin composition with less cloudiness and good dyeability.

Furthermore, the silicone compound used in the present invention preferably has a volatilization amount of 18% or less as measured by a heat loss method at 105°C for 3 hours. More preferably, the silicone compound has a volatilization amount of 10% or less. If the volatilization amount is more than 18%, there will be a problem that the amount of volatile matter from the resin will be large when the resin composition of the present invention is extruded and pelletized, and there will also be a problem that a large number of bubbles are likely to be generated in the molded product.

The silicone compound used may be linear or branched as long as it satisfies the above conditions, and various compounds having Si-H groups at side chains, terminals, branching points, or multiple sites in the molecular structure can be used.

Generally, the structure of a silicone compound containing a Si--H group in the molecule is formed by arbitrarily combining the following four types of siloxane units.
M units: monofunctional siloxane units such as ( _CH3 ) _{3SiO1/2 ,} H( _CH3 ) _{2SiO1/ 2} , _H2 ( _CH3 )SiO1 _/2 , ( _CH3 ) ₂ ( _CH2 =CH) _{SiO1 / 2} , ( _CH3 ) ₂ ( _C6H5 )SiO1 _{/ 2} , (CH3)( _C6H5 )( _CH2 =CH)SiO1 _/2, etc. D units: bifunctional siloxane units such as ( _CH3 ) _2SiO , H( _CH3 )SiO, _H2SiO , H( _C6H5 )SiO, ( _CH3 )( _CH2 = _CH )SiO, ( _C6H5 ) _2SiO , _etc. T units: ( _CH3 )SiO _{Q unit : a tetrafunctional siloxane} unit _{represented by SiO 2 .}

Specific examples of the structure of the silicone compound containing a Si _{- H group used} in the present invention include rational formulas Dn _{, Tp} , _MmDn , _MmTp , _MmQq , MmDnTp _{, MmDnQq , MmTpQq} , _MmDnTpQq , _DnTp , _DnQq , _{and DnTpQq . Of these , preferred} structures of _the silicone compound _{are MmDn , MmTp , MmDnTp , and MmDnQq , and more preferred structures are MmDn or MmDnTp .}
(The coefficients m, n, p, and q in the above rational formula are integers that represent the degree of polymerization of each siloxane unit. Furthermore, when any of m, n, p, and q is a value of 2 or more, the siloxane unit with that coefficient can be two or more types of siloxane units having different hydrocarbon groups having 1 to 20 carbon atoms that may have a bonded hydrogen atom or a heteroatom-containing functional group.)

Here, the sum of the coefficients in each rational formula is the average degree of polymerization of the silicone compound. In the present invention, the average degree of polymerization is preferably 3 to 150, more preferably 4 to 80, and even more preferably 5 to 60. If it is below this preferred range, the volatility of the silicone compound itself becomes high, and there is a problem that the resin composition containing the silicone compound is likely to volatilize in large amounts during processing. If it exceeds this preferred range, the resin composition containing the silicone compound is likely to have insufficient flame retardancy and transparency. The above silicone compounds may be used alone or in combination of two or more.

Such silicone compounds having Si-H bonds can be produced by conventional methods. For example, the target compound can be obtained by co-hydrolyzing the corresponding organochlorosilanes according to the structure of the target silicone compound and removing the by-products such as hydrochloric acid and low boiling points. In addition, when silicone oils having a hydrocarbon group with 1 to 20 carbon atoms, which may have Si-H bonds, aromatic groups represented by the general formula [10], or other heteroatom-containing functional groups in the molecule, cyclic siloxanes, or alkoxysilanes are used as starting materials, the target silicone compound can be obtained by using an acid catalyst such as hydrochloric acid, sulfuric acid, or methanesulfonic acid, optionally adding water for hydrolysis, proceeding with the polymerization reaction, and then similarly removing the acid catalyst and low boiling points used.

Further, the silicone compound containing Si-H groups has siloxane units M, M ^H , D, D ^H , D ^φ2 , T, and T ^φ represented by the following structural formula (wherein M is (CH ₃ ) ₃ SiO _1/2
M ^H : H(CH ₃ ) ₂ SiO _1/2 D: (CH ₃ ) ₂ SiOD ^H : H(CH ₃ )SiO ^φ2 : (C ₆ H ₅ ) ₂ SiT: (CH ₃ )SiO _3/2 T ^φ : (C ₆ H ₅ )SiO _3/2 and assuming that the average numbers of siloxane units per molecule are m, _mh , d, _dh , _dp2 , t and _tp, respectively, it is preferable that all of the following relational expressions are satisfied.
2 ≦ m+m _h ≦ 40
0.35 ≦ d+d _h +d _p2 ≦ 148
0 ≦ t+t _p ≦ 38
0.35 ≦ m _h + d _h ≦ 110
If the above range is not satisfied, it becomes difficult to simultaneously achieve good flame retardancy and excellent transparency in the resin composition of the present invention, and in some cases it becomes difficult to produce the silicone compound containing Si-H groups.

When a silicone compound is included as a flame retardant, the content is preferably 0.1 to 7 parts by weight, more preferably 0.1 to 4 parts by weight, even more preferably 0.1 to 2 parts by weight, and particularly preferably 0.1 to 1 part by weight, per 100 parts by weight of component A. If the content exceeds this preferred range, the heat resistance of the resin may decrease and gas may be more likely to be generated during processing, and if the content is below this preferred range, flame retardancy may not be achieved.

(ii) Fluorine-containing drip-preventing agent The resin composition of the present invention may contain a fluorine-containing drip-preventing agent. By containing this fluorine-containing drip-preventing agent, good flame retardancy can be achieved without impairing the physical properties of the molded article.

Fluorine-containing anti-dripping agents include fluorine-containing polymers that have fibril-forming ability, such as polytetrafluoroethylene, tetrafluoroethylene-based copolymers (e.g., tetrafluoroethylene/hexafluoropropylene copolymers, etc.), partially fluorinated polymers such as those shown in U.S. Pat. No. 4,379,910, and polycarbonate resins produced from fluorinated diphenols. Of these, polytetrafluoroethylene (hereinafter sometimes referred to as PTFE) is preferred.

PTFE with fibril-forming ability has an extremely high molecular weight, and shows a tendency to bond PTFE together and become fibrous due to external action such as shear force. Its molecular weight is preferably 1 million to 10 million, more preferably 2 million to 9 million, in number average molecular weight calculated from standard specific gravity. Such PTFE can be used in solid form or in aqueous dispersion form. Furthermore, such PTFE with fibril-forming ability can be used in a mixed form with other resins to improve dispersibility in resins and obtain even better flame retardancy and mechanical properties.

PTFE in a mixed form can be prepared by (1) mixing an aqueous dispersion of PTFE with an aqueous dispersion or solution of an organic polymer and co-precipitating to obtain a coagulated mixture (methods described in JP-A-60-258263, JP-A-63-154744, etc.), (2) mixing an aqueous dispersion of PTFE with dried organic polymer particles (method described in JP-A-4-272957), or (3) homogeneously mixing an aqueous dispersion of PTFE with a solution of organic polymer particles and simultaneously extracting each medium from the mixture. (4) a method of polymerizing a monomer that forms an organic polymer in an aqueous dispersion of PTFE (method described in JP-A-06-220210, JP-A-08-188653, etc.), and (5) a method of homogeneously mixing an aqueous dispersion of PTFE and an organic polymer dispersion, and then polymerizing a vinyl monomer in the mixed dispersion to obtain a mixture (method described in JP-A-11-29679, etc.) can be used.

The proportion of PTFE in the mixed form is preferably 1 to 60% by weight, more preferably 5 to 55% by weight, based on 100% by weight of the PTFE mixture. If it is within this preferred range, good dispersibility of PTFE can be achieved.

When a fluorine-containing drip-preventing agent is included as a flame retardant, the content is preferably 0.01 to 5 parts by weight, more preferably 0.05 to 1.5 parts by weight, and even more preferably 0.1 to 1 part by weight, per 100 parts by weight of component A. If the content of the fluorine-containing drip-preventing agent is less than 0.01 part by weight, the flame retardancy may be insufficient, and if it exceeds 5 parts by weight, PTFE may precipitate on the surface of the molded article, resulting in a poor appearance, as well as increasing the cost of the resin composition.

(Production of transparent antibacterial polycarbonate resin composition)
Any method may be adopted for producing the transparent antibacterial polycarbonate resin composition of the present invention. For example, the A and B components, and optionally the C to E components and other additives are thoroughly mixed using a premixing means such as a V-type blender, a Henschel mixer, a mechanochemical device, an extrusion mixer, or the like, and then the premix is granulated as necessary using an extrusion granulator or a briquetting machine, and then melt-kneaded using a melt kneader such as a vented twin-screw extruder, followed by pelletization using equipment such as a pelletizer.

(Production of molded articles made of transparent antibacterial polycarbonate resin compositions)
The transparent antibacterial polycarbonate resin composition of the present invention can be injection molded from pellets obtained by the above-mentioned method to produce various molded products. In such injection molding, not only the usual cold runner type molding method but also a hot runner that enables runnerless production can be used. In addition, in the injection molding, not only the usual molding method but also gas-assisted injection molding, injection compression molding, ultra-high speed injection molding, injection press molding, two-color molding, sandwich molding, in-mold coating molding, insert molding, foam molding (including those using supercritical fluids), rapid heating and cooling mold molding, heat insulating mold molding, and in-mold remelting molding, as well as molding methods consisting of combinations thereof, can be used.

The resin composition of the present invention can also be used in the form of various profile extrusion products, sheets, films, etc., by extrusion molding. Sheets and films can also be molded by inflation, calendaring, casting, etc. Furthermore, it can be molded into heat shrinkable tubes by subjecting it to a specific stretching operation. The resin composition of the present invention can also be molded into molded products by rotational molding, blow molding, etc.

Furthermore, molded articles formed from resin compositions can be subjected to various types of surface treatments, including decorative painting, hard coating, water- and oil-repellent coating, hydrophilic coating, ultraviolet absorbing coating, infrared absorbing coating, electromagnetic wave absorbing coating, heat-generating coating, antistatic coating, antistatic coating, conductive coating, and metallizing (plating, chemical vapor deposition (CVD), physical vapor deposition (PVD), thermal spraying, etc.).

(Transparency)
In the transparent antibacterial polycarbonate resin of the present invention, the haze value measured in a 2 mm-thick molded article made of the resin composition in accordance with JIS K 7136 is less than 50%, preferably less than 30%, and more preferably less than 10%.

(Impact resistance)
In the transparent antibacterial polycarbonate resin composition of the present invention, the notched Charpy impact strength of test pieces made of the resin composition conditioned at 23°C and -30°C in accordance with ISO 179 is preferably 15 kJ/m2 or ^more , more preferably 20 kJ/ ^m2 or more, and even more preferably 30 kJ/m2 or ^more . If the strength is below this preferred range, it is difficult to apply the composition to outdoor structural members for cold regions, various housing members, and automobile-related parts.

(Antibacterial)
In the transparent antibacterial polycarbonate resin composition of the present invention, the antibacterial activity value against Staphylococcus aureus and Escherichia coli in accordance with JIS Z 2801 for a test piece made of the resin composition is preferably 2.0 or more, more preferably 3.0 or more, even more preferably 4.0 or more, and particularly preferably 5.0 or more. If the antibacterial activity value is less than 2.0, it can be said that the antibacterial effect is insufficient.

The present invention will be described in more detail below with reference to examples, but these are not intended to limit the present invention. Unless otherwise specified, parts in the examples are parts by weight and percentages are percentages by weight. Evaluations were performed according to the following methods.

1. Evaluation of Polycarbonate-Polydiorganosiloxane Copolymer Resin (Component A-1) (1) Viscosity Average Molecular Weight (Mv)
The specific viscosity (η _SP ) calculated by the following formula was determined using an Ostwald viscometer from a solution prepared by dissolving 0.7 g of polycarbonate-polydiorganosiloxane copolymer resin in 100 ml of methylene chloride at 20° C.
Specific viscosity (η _SP )=(t−t ₀ )/t ₀
[ _t0 is the number of seconds that methylene chloride falls, and t is the number of seconds that the sample solution falls]
The viscosity average molecular weight Mv was calculated from the determined specific viscosity (η _SP ) according to the following formula.
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

(2) Polydiorganosiloxane component content and average chain length p+q
^{The 1} H-NMR spectrum of the polycarbonate-polydiorganosiloxane copolymer resin was measured using an NMR JNM-AL400 manufactured by JEOL Ltd., and the integral ratio of the peak derived from the dihydric phenol (I) was compared with the integral ratio of the peak derived from the hydroxyaryl-terminated polydiorganosiloxane (II) to calculate the average chain length p+q. Similarly, the integral ratio of the peak derived from the hydroxyaryl terminal was compared with the integral ratio of the peak derived from the polydiorganosiloxane to calculate the average chain length p+q.

(3) Average Domain Size and Normalized Dispersion of Polydiorganosiloxane Domains Using a three-stage plate (width 50 mm, length 90 mm, thickness from the gate side 3.0 mm (length 20 mm), 2.0 mm (length 45 mm), 1.0 mm (length 25 mm)) prepared by the following method, the average size and particle size distribution (normalized dispersion) of the polydiorganosiloxane domains at the intersection 5 mm from the end and 5 mm from the side of the 1.0 mm thick part were measured using an X-ray diffraction device (RINT-TTRII manufactured by Rigaku Corporation). The X-ray source was CuKα characteristic X-rays (wavelength 0.1541841 nm), tube voltage 50 kV, tube current 300 mA. The small angle scattering optical system was Slit: 1st 0.03 mm, HS 10 mm, SS 0.2 mm, RS 0.1 mm. The measurements were performed by asymmetric scanning (2θ scan) with FT 0.01° step, 4 sec/step, and scan range 0.06-3°. Small angle scattering analysis software NANO-Solver (Ver. 3.3) manufactured by Rigaku Corporation was used for curve fitting analysis. The analysis was performed using an isolated particle model that does not consider interparticle interactions (interparticle interference) and assumes an aggregate structure in which spherical domains of polydiorganosiloxane are dispersed in a polycarbonate polymer matrix and that there is variation in particle size distribution, with the density of the polycarbonate matrix set to 1.2 g/cm ³ and the density of the polydiorganosiloxane domain set to 1.1 g/cm ³ .

2. Production of Polycarbonate-Polydiorganosiloxane Copolymer Resin (Component A-1) In the Examples and Comparative Examples, the polydiorganosiloxane compound shown in (II)-1 below was used as the dihydric phenol (II) having a polydiorganosiloxane structure.
(II)-1: p+q=40 (Shin-Etsu Chemical Co., Ltd.; KF-2201)
PC-POS-1 and PC-POS-2 were produced in the following manner.

(Production method of PC-POS-1)
A reactor equipped with a thermometer, a stirrer, and a reflux condenser was charged with 21,592 parts of ion-exchanged water and 3,675 parts of a 48.5% aqueous sodium hydroxide solution, and 3,880 parts (17.00 moles) of 2,2-bis(4-hydroxyphenyl)propane (bisphenol A) as the dihydric phenol (I) represented by the general formula [4] and 7.6 parts of hydrosulfite were dissolved therein. Then, 14,565 parts of methylene chloride (10 molar equivalents with respect to the total amount of the dihydric phenol) was added, and 1,900 parts of phosgene was blown in over a period of 60 minutes at 22 to 30° C. with stirring. 7283 parts of methylene chloride (5 molar equivalents relative to the total amount of dihydric phenols) was added, 1131 parts of 48.5% aqueous sodium hydroxide solution and a solution of 108 parts of p-tert-butylphenol dissolved in 800 parts of methylene chloride (0.55 molar equivalents relative to the total amount of dihydric phenols) were added, and while stirring, a solution of 430 parts (0.137 moles) of the above KF-2201 as dihydric phenol (II) represented by the general formula [5] dissolved in 800 parts of methylene chloride (0.55 molar equivalents relative to the total amount of dihydric phenols) was added at a rate of 0.0008 molar equivalents/min relative to the dihydric phenol (I) to emulsify the mixture, and then vigorously stirred again. Under such stirring, 4.3 parts of triethylamine was added while the reaction solution was at 26°C, and the reaction was terminated by continuing stirring at a temperature of 26 to 31°C for 1 hour. After the reaction was completed, the organic phase was separated, diluted with methylene chloride, washed with water, and then acidified with hydrochloric acid and washed with water. When the conductivity of the aqueous phase was almost the same as that of ion-exchanged water, the mixture was placed in a kneader filled with warm water and the methylene chloride was evaporated while stirring to obtain a polycarbonate-polydiorganosiloxane copolymer powder. After dehydration, the mixture was dried at 120°C for 12 hours in a hot air circulation dryer. In the obtained polycarbonate-polydiorganosiloxane copolymer, the average chain length p+q of the polydiorganosiloxane was 37, the viscosity average molecular weight was 20,100, the polydiorganosiloxane component content was 8.4% by weight, and the average domain size and normalized dispersion of the polydiorganosiloxane domains were 11 nm and 21.1%, respectively.

(Production method of PC-POS-2)
The production method was the same as for PC-POS-1, except that the amount of p-tert-butylphenol was changed to 86 parts. The resulting polycarbonate-polydiorganosiloxane copolymer resin had an average polydiorganosiloxane chain length p+q of 37, a viscosity average molecular weight of 24,100, a polydiorganosiloxane component content of 8.3% by weight, and an average domain size and normalized dispersion of the polydiorganosiloxane domains of 11 nm and 20.8%, respectively.

3. Evaluation of transparent antibacterial polycarbonate resin composition (1) Transparency (haze)
A three-tiered plate (width 50 mm, length 90 mm, thickness from the gate side 3.0 mm (length 20 mm), 2.0 mm (length 45 mm), 1.0 mm (length 25 mm)) prepared by the following method was used as a test piece, and the thickness of the test piece was measured in accordance with JIS K 7136.
The haze at the 0 mm portion was measured.
The transparency was evaluated according to the following criteria.
◎: Haze is less than 10%. ○: Haze is 10% or more but less than 30%. △: Haze is 30% or more but less than 50%. ×: Haze is 50% or more.

(2) Impact resistance (notched Charpy impact strength)
Molded products (width 10 mm, length 80 mm, thickness 4.0 mm) prepared by the method described below were used as test pieces, and the notched Charpy impact strength of the test pieces conditioned at 23°C and -30°C was measured in accordance with ISO179.
The impact resistance was evaluated according to the following criteria.
◎: Notched Charpy impact strength is 30 kJ/ ^m2 or more. ○: Notched Charpy impact strength is 20 kJ/ ^m2 or more and less than 30 kJ/m2 ^. △: Notched Charpy impact strength is 15 kJ/ ^m2 or more and less than 20 kJ/ ^m2. ×: Notched Charpy impact strength is less than 15 kJ/m2 ^.

(3) Antibacterial properties (antibacterial activity value)
A square plate molded product (width 150 mm, length 150 mm, thickness 2 mm) prepared by the following method was cut to obtain a test piece (width 50 mm, length 50 mm, thickness 2 mm).
The test was carried out in accordance with 2801 under the following conditions.
* Bacteria liquid concentration: 1/500 normal bouillon medium (1/500NB)
* Amount of bacterial liquid dropped: 0.4 mL (covering film: polyethylene film with a surface area of 16 ^cm2 ) * Culture temperature and humidity: 35°C, 90% RH
*Culture time: 24 hours *Bacteria used: Staphylococcus aureus (NBRC12732), Escherichia coli (NBRC3972)
*Cleaning method: Wiping with absorbent cotton soaked in ethanol. Antibacterial properties were evaluated using antibacterial activity values according to the following criteria.
Antibacterial activity value = log ₁₀ (viable bacteria count on untreated test piece after 24 hours) - log ₁₀ (viable bacteria count on antibacterial treated test piece after 24 hours)
○: Antibacterial activity value is 2.0 or more against both of the two types of bacteria used. ×: Antibacterial activity value is less than 2.0 against at least one of the two types of bacteria used. The antibacterial treated test piece refers to a test piece made of a resin composition containing a silver-based glass antibacterial agent. On the other hand, the untreated test piece refers to a test piece made of a resin composition containing the silver-based glass antibacterial agent, from which only the silver-based glass antibacterial agent has been removed.

[Examples 1 to 17, Comparative Examples 1 to 4]
The compositions of components A to E shown in Tables 1 and 2 were mixed uniformly using a blender, and then melt-kneaded using a vented twin-screw extruder to obtain pellets. A preliminary mixture of the components with the powder of the main component A was prepared in advance, with a concentration of approximately 10 to 100 times the amount of each component mixed, and the entire mixture was mixed using a blender. The vented twin-screw extruder used was a KTX-30 (diameter 30 mmφ) manufactured by Kobe Steel, Ltd. The extrusion conditions were cylinder temperature and die temperature 280°C, screw rotation speed 200 rpm, discharge rate 20 kg/h, and vent suction degree 3 kPa. Strands were extruded and cooled in a water bath, then strand cut using a pelletizer, and pelletized.

The pellets obtained were dried in a hot air circulation dryer at 120°C for 5 hours, and then molded products for various evaluations were produced using an injection molding machine (SE130EV-A manufactured by Sumitomo Heavy Industries, Ltd.) at a cylinder temperature of 280°C and a mold temperature of 70°C. Specifically, the following (a) to (c) were produced. (a) Three-stage plate: width 50 mm, length 90 mm, thickness 3.0 mm from the gate side
m (length 20 mm), 2.0 mm (length 45 mm), 1.0 mm (length 25 mm)
(b) Molded product for Charpy impact test according to ISO 179: width 10 mm, length 80 mm, thickness 4.0 mm
(c) Square plate molded product: width 150 mm, length 150 mm, thickness 2 mm
The results of various evaluations are shown in Tables 1 and 2.

The components represented by symbols in Tables 1 and 2 are as follows:
(Component A)
A-1-1: PC-POS-1, refractive index 1.57
A-1-2: PC-POS-2, refractive index 1.57
A-2-1: Aromatic polycarbonate resin (linear aromatic polycarbonate resin powder having a repeating skeleton of 2,2-bis(4-hydroxyphenyl)propane and a viscosity average molecular weight of 19,700 and a refractive index of 1.59) (manufactured by Teijin Limited; Panlite L-1225WX (product name)),
A-2-2: Aromatic polycarbonate resin (linear aromatic polycarbonate resin powder having a repeating skeleton of 2,2-bis(4-hydroxyphenyl)propane, a viscosity average molecular weight of 23,900, and a refractive index of 1.59) (manufactured by Teijin Limited; Panlite L-1250WP (product name)),

(Component B)
B-1: Silver-based glass antibacterial agent (manufactured by Sinanen Zeomic Co., Ltd.; Zeomic KM10D (product name)), average particle size (D50): 10 μm
B-2 (for comparison): antibacterial agent containing zinc-based glass and silver-based zirconium phosphate (manufactured by Toagosei Co., Ltd.; product name: Novalon VFA701), average particle size (D50): 1.2 μm
The antibacterial agent B-2 is zirconium phosphate carrying silver ions, which falls outside the scope of claim 1.

(Component C)
C-1: Phosphorus-based stabilizer (tris(2,4-di-tert-butylphenyl)phosphite) (manufactured by ADEKA Corporation; Adeka STAB 2112 (product name))

(Component D)
D-1: Glycerin monostearate (Riken Vitamin Co., Ltd.; Rikemal S-100A (product name))
D-2: Pentaerythritol tetrastearate (product name: Unistar H-476-S, manufactured by NOF Corporation)

(Component E)
E-1: Benzotriazole-based ultraviolet absorber (manufactured by ADEKA CORPORATION; Adeka STAB LA-31 (product name))
E-2: Triazine-based ultraviolet absorber (manufactured by BASF Japan Ltd.; Tinuvin 1577ED (product name))

From Examples 1 to 17, it can be seen that by adding the silver-based glass antibacterial agent described in claim 1 of the present invention to a mixture of polycarbonate-polydiorganosiloxane copolymer resin or polycarbonate-polydiorganosiloxane copolymer resin and other polycarbonate resin, transparency and impact resistance are improved and antibacterial properties are also expressed. A comparison between Example 2 and Comparative Example 4 shows that when the silver-based glass antibacterial agent described in claim 1 of the present invention is added to a polycarbonate resin other than polycarbonate-polydiorganosiloxane copolymer resin, impact resistance is inferior. Furthermore, a comparison between Example 2 and Comparative Example 4 shows that in order to maintain transparency, it is necessary to use the silver-based glass antibacterial agent described in claim 1 of the present invention.

Claims (9)

A transparent antibacterial polycarbonate resin composition comprising 100 parts by weight of (A) a polycarbonate-polydiorganosiloxane copolymer resin (component A-1) or a mixture (component A-2) of component A-1 and a polycarbonate resin other than component A-1 which comprises a repeating unit represented by the following general formula [1], and (B) 0.3 to 5 parts by weight of a silver-based glass antibacterial agent (component B) supported on glass so that silver ions having an average particle size (D50) of 7 to 15 μm as measured by a laser diffraction/scattering method are eluted, wherein the haze of a molded article having a thickness of 2 mm and made of the resin composition is less than 50%.
[In formula [1], R ¹ and R ² each independently represent a group selected from the group consisting of a hydrogen atom, a halogen atom, an alkyl group having 1 to 18 carbon atoms, an alkoxy group having 1 to 18 carbon atoms, a cycloalkyl group having 6 to 20 carbon atoms, a cycloalkoxy group having 6 to 20 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an aryl group having 6 to 14 carbon atoms, an aryloxy group having 6 to 14 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, an aralkyloxy group having 7 to 20 carbon atoms, a nitro group, an aldehyde group, a cyano group, and a carboxy group, and when there are a plurality of each, they may be the same or different, e and f each represent an integer of 1 to 4, and W represents a single bond or at least one group selected from the group consisting of groups represented by the following formula [2].]
[In formula [2], R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ , R ¹⁶ , R ¹⁷ and R ¹⁸ each independently represent a group selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, an aryl group having 6 to 14 carbon atoms and an aralkyl group having 7 to 20 carbon atoms; R ¹⁹ and R ²⁰ each independently represents a group selected from the group consisting of a hydrogen atom, a halogen atom, an alkyl group having 1 to 18 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a cycloalkyl group having 6 to 20 carbon atoms, a cycloalkoxy group having 6 to 20 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an aryl group having 6 to 14 carbon atoms, an aryloxy group having 6 to 10 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, an aralkyloxy group having 7 to 20 carbon atoms, a nitro group, an aldehyde group, a cyano group, and a carboxy group, and when there are a plurality of such groups, they may be the same or different, g is an integer from 1 to 10, and h is an integer from 4 to 7.] 2. The transparent antibacterial polycarbonate resin composition according to claim 1, wherein the component A-1 is a polycarbonate-polydiorganosiloxane copolymer resin containing a repeating unit represented by the following general formula [3]:
[In formula [3], R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ 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; R ⁹ and R ¹⁰ are each independently a hydrogen atom, a halogen atom, an alkyl group having 1 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms; p is a natural number; q is 0 or a natural number; and p+q is a natural number from 30 to 50. X is a divalent aliphatic group having 2 to 8 carbon atoms.] 3. The transparent antibacterial polycarbonate resin composition according to claim 2, wherein R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ in the general formula [3] are methyl groups. The transparent antibacterial polycarbonate resin composition according to claim 2 or 3, characterized in that the repeating unit represented by the above general formula [3] is a repeating unit derived from (2-allylphenol)-terminated polydiorganosiloxane or (2-methoxy-4-allylphenol)-terminated polydiorganosiloxane. The transparent antibacterial polycarbonate resin composition according to any one of claims 1 to 4, characterized in that the content of component A-1 is 5 to 100 parts by weight per 100 parts by weight of the total of components A-1 and A-2. A transparent antibacterial polycarbonate resin composition according to any one of claims 2 to 5, characterized in that the content of the polydiorganosiloxane block represented by the general formula [3] is 0.5 to 20% by weight based on the total weight of component A. The transparent antibacterial polycarbonate resin composition according to any one of claims 2 to 6, characterized in that component A-1 is an aggregate structure in which polydiorganosiloxane domains are dispersed in a polycarbonate resin matrix, the average size of the polydiorganosiloxane domains is 5 to 15 nm, and the normalized dispersion is 25% or less. 8. The transparent antibacterial polycarbonate resin composition according to any one of claims 1 to 7, characterized in that it contains, relative to 100 parts by weight of component A, 0.01 to 0.1 parts by weight of (C) a phosphorus-based stabilizer (component C), 0.1 to 1 part by weight of (D) a release agent (component D), and 0 to 1 part by weight of (E) an ultraviolet absorbing agent (component E). A molded article obtained by molding the transparent antibacterial polycarbonate resin composition according to any one of claims 1 to 8 .