JP6835564B2 - Polycarbonate resin composition for optical components - Google Patents

Description

The present invention relates to a polycarbonate resin composition for optical parts, and more particularly to a polycarbonate resin composition for optical parts, which has a good hue and improved moisture and heat resistance.

Liquid crystal display devices used in personal computers, mobile phones, and the like incorporate a planar light source device in order to meet the demands for thinning, weight reduction, labor saving, and high definition. The planar light source device is provided with a light guide plate having a flat plate shape or the like for the purpose of uniformly and efficiently guiding the incoming light to the liquid crystal display side.

Such a light guide plate is obtained by injection molding of a thermoplastic resin. Conventionally, the light guide plate has been molded from a resin material such as polymethyl methacrylate (PMMA), but recently, there is a demand for a display device that displays a clearer image, and the heat generated in the vicinity of the light source raises the temperature inside the device. Because of this tendency, it is being replaced by a polycarbonate resin material with higher heat resistance.

Polycarbonate resin is excellent in mechanical properties, thermal properties, electrical properties, and weather resistance, but since the light transmittance is lower than that of PMMA, etc., a surface light source body is formed from a light guide plate made of polycarbonate resin and a light source. When configured, there is a problem that the brightness is low. Recently, it has been required to reduce the difference in chromaticity between the light input portion of the light guide plate and the place away from the light input portion, but there is a problem that the polycarbonate resin is more likely to turn yellow than the PMMA resin.

Patent Document 1 describes a method of improving light transmittance and brightness by adding an acrylic resin and an alicyclic epoxy, and Patent Document 2 describes a method of modifying the end of a polycarbonate resin to provide transferability of an uneven portion to a light guide plate. A method of improving the brightness by increasing the brightness, Patent Document 3 proposes a method of improving the brightness by introducing a copolyester carbonate having an aliphatic segment to improve the transferability.
However, in the method of Patent Document 1, although the hue is improved by adding the acrylic resin, the light transmittance and the brightness cannot be increased because it becomes cloudy, and the transmittance is improved by adding the alicyclic epoxy. However, the effect of improving hue is not observed. In the case of Patent Document 2 and Patent Document 3, although the effect of improving fluidity and transferability can be expected, there is a drawback that the heat resistance is lowered.

On the other hand, it is known in Patent Document 4 and Patent Document 5 that polyethylene glycol, poly (2-methyl) ethylene glycol and the like are blended with a thermoplastic resin such as a polycarbonate resin. Then, the applicant in Patent Document 6 describes the formula: X-О- [CH (-R) -CH _2- O] _n- Y (in the formula, R is a hydrogen atom or an alkyl having 1 to 3 carbon atoms. A proposal was made to improve the transmittance and hue by blending polyethylene glycol or poly (2-alkyl) ethylene glycol represented by (group).

However, especially recently, in various mobile terminals such as smartphones and tablet terminals, thinning and large-sized thinning are progressing at a remarkable speed, and the required specifications are increasing for such high-end light guide plates. It is becoming more sophisticated.

Japanese Unexamined Patent Publication No. 11-158364 Japanese Unexamined Patent Publication No. 2001-208917 Japanese Unexamined Patent Publication No. 2001-215336 Japanese Unexamined Patent Publication No. 1-22959 Japanese Unexamined Patent Publication No. 9-227785 Japanese Patent No. 4069364

However, it has been found that the polycarbonate resin composition containing the polyalkylene glycol as described above has a problem in moisture and heat resistance, especially when molding a thin-walled molded product such as a light guide plate for high-end products.
An object (object) of the present invention is to provide a polycarbonate resin composition for an optical component having a good hue and excellent moisture and heat resistance.

As a result of diligent studies to achieve the above problems, the present inventor has added a polyalkylene glycol having an epoxy group at the terminal to the polyalkylene glycol, and a phosphorus-based stabilizer. However, they have found that they have excellent moisture resistance and heat resistance while having an excellent hue, and have completed the present invention.
The present invention relates to the following polycarbonate resin compositions for optical components.

[1] With respect to 100 parts by mass of the polycarbonate resin (A), 0.1 to 4 parts by mass of the polyalkylene glycol (B) having no epoxy group at the end and the polyalkylene glycol (C) having an epoxy group at the end are used. A polycarbonate resin composition for an optical component, which contains 0.005 to 2 parts by mass and 0.005 to 0.5 parts by mass of a phosphorus-based stabilizer (D).
[2] The polycarbonate resin composition for optical components according to the above [1], wherein the alkylene group of the polyalkylene glycol (C) having an epoxy group at the terminal has 3 or more carbon atoms.
[3] The mass ratio of the content of the polyalkylene glycol (B) having no epoxy group at the terminal to the polyalkylene glycol (C) having an epoxy group at the end is 30:70 to 99: 1 as described above [1]. ] Or [2]. The polycarbonate resin composition for an optical component.
[4] The polycarbonate resin composition for optical components according to any one of the above [1] to [3], wherein the polyalkylene glycol (C) having an epoxy group at the terminal has an epoxy equivalent of 200 to 1000 g / eq.
[5] The total content of the polyalkylene glycol (B) having no epoxy group at the terminal and the polyalkylene glycol (C) having an epoxy group at the end is 0. 0 with respect to 100 parts by mass of the polycarbonate resin (A). The polycarbonate resin composition for an optical component according to any one of the above [1] to [4], which is 2 to 3 parts by mass.
[6] An optical component comprising the polycarbonate resin composition for an optical component according to any one of the above [1] to [5].

The polycarbonate resin composition for optical components of the present invention has a good hue, excellent moisture and heat resistance, and excellent fluidity and high light transmittance.

Hereinafter, the present invention will be described in detail with reference to embodiments and examples.
In addition, in this specification, "~" is used in the meaning which includes the numerical values described before and after it as the lower limit value and the upper limit value unless otherwise specified.

The polycarbonate resin composition for optical components of the present invention contains 0.1 to 4 parts by mass of polyalkylene glycol (B) having no epoxy group at the terminal and an epoxy group at the terminal with respect to 100 parts by mass of the polycarbonate resin (A). It is characterized by containing 0.005 to 2 parts by mass of the polyalkylene glycol (C) having the above and 0.005 to 0.5 parts by mass of the phosphorus-based stabilizer (D).
Hereinafter, each component and the like constituting the polycarbonate resin composition for optical components of the present invention will be described in detail.

[Polycarbonate resin (A)]
The polycarbonate resin is a polymer having a basic structure having a carbonic acid bond represented by the formula:-[-O-X-OC (= O)-]-. In the formula, X is generally a hydrocarbon, but X with a heteroatom or a heterobond introduced may be used to impart various properties.

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

The specific type of the polycarbonate resin is not limited, and examples thereof include a polycarbonate polymer obtained by reacting a dihydroxy compound with a carbonate precursor. At this time, in addition to the dihydroxy compound and the carbonate precursor, a polyhydroxy compound or the like may be reacted. Further, a method of reacting carbon dioxide with cyclic ether using carbon dioxide as a carbonate precursor may also be used. Further, the polycarbonate polymer may be linear or branched. Further, the polycarbonate polymer may be a copolymer composed of one type of repeating unit or a copolymer having two or more types of repeating units. At this time, as the copolymer, various copolymer forms such as a random copolymer and a block copolymer can be selected. Usually, such a polycarbonate polymer becomes a thermoplastic resin.

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

2,2'-Dihydroxy-1,1'-binaphthyl, 1,2-dihydroxynaphthalene, 1,3-dihydroxynaphthalene, 2,3-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, 1 , 7-Dihydroxynaphthalene, 2,7-dihydroxynaphthalene and other dihydroxynaphthalene;

2,2'-Dihydroxydiphenyl ether, 3,3'-dihydroxydiphenyl ether, 4,4'-dihydroxydiphenyl ether, 4,4'-dihydroxy-3,3'-dimethyldiphenyl ether, 1,4-bis (3-hydroxyphenoxy) Dihydroxydiaryl ethers such as benzene and 1,3-bis (4-hydroxyphenoxy) benzene;

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

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

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

4,4'-Dihydroxydiphenylsulfide,
Dihydroxydiarylsulfides such as 4,4'-dihydroxy-3,3'-dimethyldiphenylsulfide;

Dihydroxydiarylsulfoxides such as 4,4'-dihydroxydiphenylsulfoxide, 4,4'-dihydroxy-3,3'-dimethyldiphenylsulfoxide;

4,4'-Dihydroxydiphenyl sulfone,
Dihydroxydiaryl sulfones such as 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfone;
And so on.

Among these, bis (hydroxyaryl) alkanes are preferable, and bis (4-hydroxyphenyl) alkanes are particularly preferable, and 2,2-bis (4-hydroxyphenyl) propane (particularly from the viewpoint of impact resistance and heat resistance). That is, bisphenol A) is preferable.
As the aromatic dihydroxy compound, one type may be used, or two or more types may be used in any combination and ratio.

Further, to give an example of a monomer which is a raw material of an aliphatic polycarbonate resin,
Ethan-1,2-diol, propane-1,2-diol, propane-1,3-diol, 2,2-dimethylpropane-1,3-diol, 2-methyl-2-propylpropane-1,3- Alkanediols such as diols, butane-1,4-diols, pentane-1,5-diols, hexane-1,6-diols and decane-1,10-diols;

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

Glycos such as ethylene glycol, 2,2'-oxydiethanol (ie, diethylene glycol), triethylene glycol, propylene glycol, spiroglycol;

1,2-Benzene dimethanol, 1,3-benzenedimethanol, 1,4-benzenedimethanol, 1,4-benzenediethanol, 1,3-bis (2-hydroxyethoxy) benzene, 1,4-bis ( 2-Hydroxyethoxy) benzene, 2,3-bis (hydroxymethyl) naphthalene, 1,6-bis (hydroxyethoxy) naphthalene, 4,4'-biphenyldimethanol, 4,4'-biphenyldiethanol, 1,4- Aralkyldiols such as bis (2-hydroxyethoxy) biphenyl, bisphenol A bis (2-hydroxyethyl) ether, bisphenol S bis (2-hydroxyethyl) ether;

1,2-Epoxide ethane (ie, ethylene oxide), 1,2-epoxide propane (ie, propylene oxide), 1,2-epoxide cyclopentane, 1,2-epoxide cyclohexane, 1,4-epoxide cyclohexane, 1-methyl Cyclic ethers such as -1,2-epoxide cyclohexane, 2,3-epoxide norbornane, and 1,3-epoxide propane; and the like.

Among the monomers used as raw materials for the polycarbonate resin, carbonyl halide, carbonate ester and the like are used as an example of the carbonate precursor. As the carbonate precursor, one kind may be used, or two or more kinds may be used in any combination and ratio.

Specific examples of the carbonyl halide include phosgene; a bischloroformate of a dihydroxy compound, a haloformate of a monochloroformate of a dihydroxy compound, and the like.

Specific examples of the carbonate ester include diaryl carbonates such as diphenyl carbonate and ditril carbonate; dialkyl carbonates such as dimethyl carbonate and diethyl carbonate; biscarbonate of dihydroxy compound, monocarbonate of dihydroxy compound, and cyclic carbonate. Examples thereof include carbonates of dihydroxy compounds such as.

The method for producing the polycarbonate resin is not particularly limited, and any method can be adopted. Examples thereof include an interfacial polymerization method, a melt transesterification method, a pyridine method, a ring-opening polymerization method of a cyclic carbonate compound, and a solid phase transesterification method of a prepolymer.

The molecular weight of the polycarbonate resin (A) is preferably 1000 to 18000, more preferably 10500 or more, still more preferably 11000 or more, particularly preferably 11500 or more, and most preferably 12000 or more in terms of viscosity average molecular weight (Mv). Yes, more preferably 17500 or less, still more preferably 17000 or less, and particularly preferably 16500 or less. By setting the viscosity average molecular weight to the lower limit of the above range or more, the mechanical strength of the polycarbonate resin composition of the present invention can be further improved, and by setting the viscosity average molecular weight to the upper limit of the above range or less, the present invention It is possible to suppress and improve the decrease in fluidity of the polycarbonate resin composition of the present invention, improve the molding processability, and facilitate the thin-wall molding process.
The polycarbonate resin (A) may be used by mixing two or more types of polycarbonate resins having different viscosity average molecular weights. In this case, a polycarbonate resin having a viscosity average molecular weight outside the above-mentioned suitable range is mixed. You may.

In the present invention, the viscosity average molecular weight Mv of the polycarbonate resin is determined by using methylene chloride as a solvent and determining the ultimate viscosity η (unit: dl / g) at a temperature of 20 ° C. using an Ubbelohde viscometer. It means the value calculated from the formula.
η = 1.23 × 10 ^-4 Mv ^0.83
The ultimate viscosity η is a value calculated by the following formula by measuring _{the specific viscosity η sp} at each solution concentration [C] (g / dl).

The polycarbonate resin is not limited to the embodiment containing only one type of polycarbonate resin, and is used in the sense of including, for example, a mode containing a plurality of types of polycarbonate resins having different monomer compositions and molecular weights. ), Or a combination of an alloy (mixture) of a polycarbonate resin and another thermoplastic resin may be used. Further, for example, a polycarbonate resin is a copolymer of an oligomer or a polymer having a siloxane structure for the purpose of further improving flame retardancy and impact resistance; a phosphorus atom for the purpose of further improving thermal oxidation stability and flame retardancy. Copolymer with a monomer, oligomer or polymer having a dihydroxyanthraquinone structure; a copolymer with a monomer, oligomer or polymer having a dihydroxyanthraquinone structure for the purpose of improving thermal oxidation stability; polystyrene or the like to improve the optical properties. Even if it is configured as a copolymer mainly composed of a polycarbonate resin, such as a copolymer with an oligomer or a polymer having an olefin structure; a copolymer with a polyester resin oligomer or a polymer for the purpose of improving chemical resistance; Good.

Further, in order to improve the appearance and fluidity of the molded product, the polycarbonate resin may contain a polycarbonate oligomer. The viscosity average molecular weight (Mv) of this polycarbonate oligomer is usually 1500 or more, preferably 2000 or more, and usually 9500 or less, preferably 9000 or less. Further, the contained polycarbonate ligomer is preferably 30% by mass or less of the polycarbonate resin (including the polycarbonate oligomer).

Further, the polycarbonate resin may be not only a virgin raw material but also a polycarbonate resin recycled from a used product (so-called material recycled polycarbonate resin).
However, the regenerated polycarbonate resin is preferably 80% by mass or less, and more preferably 50% by mass or less of the polycarbonate resin. Since the regenerated polycarbonate resin is likely to be deteriorated by heat deterioration, aging deterioration, etc., if such a polycarbonate resin is used in a larger amount than the above range, the hue and mechanical properties can be deteriorated. Because it has sexual characteristics.

[Polyalkylene glycol compound (B) having no epoxy group at the terminal]
The polycarbonate resin composition for optical components of the present invention contains 0.1 to 4 parts by mass of polyalkylene glycol (B) having no epoxy group at the terminal with respect to 100 parts by mass of the polycarbonate resin (A).

As the polyalkylene glycol (B) having no epoxy group at the terminal, various polyalkylene glycols can be used, for example, a branched polyalkylene glycol represented by the following general formula (1) or the following general formula (2). The linear polyalkylene glycol represented by is preferable. The branched polyalkylene glycol represented by the following general formula (1) or the linear polyalkylene glycol represented by the following general formula (2) may be a copolymer with another copolymerization component. It is good, but it is preferably a copolymer.

(In the formula, R represents an alkyl group having 1 to 3 carbon atoms, and X and Y independently represent a hydrogen atom, an aliphatic acyl group having 1 to 23 carbon atoms, an alkyl group having 1 to 23 carbon atoms, and carbon. It represents an aryl group of number 6 to 22 or an aralkyl group having 7 to 23 carbon atoms, and m represents an integer of 10 to 400.)
The branched polyalkylene glycol represented by the general formula (1) may be a homopolymer composed of a kind of R or a copolymer composed of a different R.

(In the formula, X and Y are independently hydrogen atoms, aliphatic acyl groups having 2 to 23 carbon atoms, alkyl groups having 1 to 23 carbon atoms, aryl groups having 6 to 22 carbon atoms, or 7 to 23 carbon atoms, respectively. Indicates the aralkyl group of, p is an integer of 2 to 6, and r is an integer of 6 to 100.)
The linear polyalkylene glycol represented by the general formula (2) may be a homopolymer composed of a kind of p or a copolymer composed of different p.

As the branched polyalkylene glycol, in the general formula (1), (2-methyl) ethylene glycol in which X and Y are hydrogen atoms and R is a methyl group and (2-ethyl) ethylene glycol in which an ethyl group is preferable are preferable. ..

As the linear polyalkylene glycol, X and Y in the general formula (2) are hydrogen atoms, polyethylene glycol having p of 2, polytrimethylethylene glycol having p of 3, and polytetramethylene having p of 4. Glycols, polypentamethylene glycol having a p of 5 and polyhexamethylene glycol having a p of 6 are preferable, and polytrimethylene glycol and polytetramethylene glycol are more preferable.

The polyalkylene glycol (B) is selected from the linear alkylene ether unit (P1) represented by the following general formula (3) and the unit represented by the following general formulas (4-1) to (4-4). Polyalkylene glycol copolymers having a branched alkylene ether unit (P2) are also preferred.

(In equation (3), p represents an integer of 2 to 6.)
The linear alkylene ether unit represented by the general formula (3) may be a single unit composed of a kind of p, or a plurality of units composed of different ps may be mixed.

(In formulas (4-1) to (4-4), R ^{1 to} R ¹⁰ each independently represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and are respectively formulas (4-1) to (4-4). In 4), ^{at least one of R 1 to} R ¹⁰ is an alkyl group having 1 to 3 carbon atoms.)

As the linear alkylene ether unit (P1) represented by the general formula (3), when it is described as a glycol, ethylene glycol having p of 2, trimethylene glycol having p of 3, and tetra having p of 4 are described. Examples thereof include methylene glycol, pentamethylene glycol having p of 5, hexamethylene glycol having p of 6, and these may be mixed, preferably trimethylene glycol and tetramethylene glycol, and tetramethylene glycol is particularly preferable.

Trimethylene glycol is industrially obtained by hydroformylation of ethylene oxide to obtain 3-hydroxypropionaldehyde, which is hydrogenated, or 3-hydroxypropionaldehyde obtained by hydrating acrolein is hydrogenated with a Ni catalyst. Manufactured by the method. Recently, glycerin, glucose, starch and the like have been reduced to microorganisms to produce trimethylene glycol by a biomethod.

When this is described as glycol as the branched alkylene ether unit represented by the above general formula (4-1), (2-methyl) ethylene glycol, (2-ethyl) ethylene glycol, (2,2-dimethyl) ethylene glycol, etc. These may be mixed, and (2-methyl) ethylene glycol and (2-ethyl) ethylene glycol are preferable.

When this is described as glycol as the branched alkylene ether unit represented by the above general formula (4-2), (2-methyl) trimethylene glycol, (3-methyl) trimethylene glycol, (2-ethyl) trimethylene glycol , (3-Eethyl) triethylene glycol, (2,2-dimethyl) trimethylene glycol, (2,2-methylethyl) trimethylene glycol, (2,2-diethyl) trimethylene glycol (ie, neopentyl glycol) , (3,3-dimethyl) trimethylene glycol, (3,3-methylethyl) trimethylene glycol, (3,3-diethyl) trimethylene glycol and the like, and these may be mixed.

When this is described as glycol as the branched alkylene ether unit represented by the above general formula (4-3), (3-methyl) tetramethylene glycol, (4-methyl) tetramethylene glycol, (3-ethyl) tetramethylene glycol , (4-Ethyl) tetramethylene glycol, (3,3-dimethyl) tetramethylene glycol, (3,3-methylethyl) tetramethylene glycol, (3,3-diethyl) tetramethylene glycol, (4,4-dimethyl) ) Tetramethylene glycol, (4,4-methylethyl) tetramethylene glycol, (4,4-diethyl) tetramethylene glycol, etc. may be mixed, and (3-methyl) tetramethylene glycol may be used. preferable.

When this is described as a glycol as the branched alkylene ether unit represented by the above general formula (4-4), (3-methyl) pentamethylene glycol, (4-methyl) pentamethylene glycol, and (5-methyl) pentamethylene glycol , (3-Ethyl) pentamethylene glycol, (4-ethyl) pentamethylene glycol, (5-ethyl) pentamethylene glycol, (3,3-dimethyl) pentamethylene glycol, (3,3-methylethyl) pentamethylene glycol , (3,3-diethyl) pentamethylene glycol, (4,4-dimethyl) pentamethylene glycol, (4,4-methylethyl) pentamethylene glycol, (4,4-diethyl) pentamethylene glycol, (5,5) -Diol) pentamethylene glycol, (5,5-methylethyl) pentamethylene glycol, (5,5-diethyl) pentamethylene glycol and the like can be mentioned, and these may be mixed.

As described above, the units represented by the general formulas (4-1) to (4-4) constituting the branched alkylene ether unit have been described with glycol as an example for convenience, but the present invention is not limited to these glycols, and these alkylene oxides are not limited to these glycols. Alternatively, these polyether-forming derivatives may be used.

As a preferable polyalkylene glycol copolymer, a copolymer composed of a tetramethylene ether unit and a unit represented by the general formula (4-3) is preferable, and a tetramethylene ether unit and 3-methyltetramethylene are particularly preferable. A copolymer composed of ether units is more preferable. Further, a copolymer composed of a tetramethylene ether unit and a unit represented by the general formula (4-1) is also preferable, and in particular, a copolymer composed of a tetramethylene ether unit and a 2-methylethylene ether unit, and a tetramethylene ether. A copolymer consisting of a unit and a 2-ethylethylene ether unit is more preferable. Further, a copolymer composed of a tetramethylene ether unit and the general formula (4-2) is also preferable, and a copolymer composed of a 2,2-dimethyltrimethylene ether unit, that is, a neopentyl glycol ether unit is also preferable.

The polyalkylene glycol copolymer may be a random copolymer or a block copolymer.

The linear alkylene ether unit (P1) represented by the general formula (3) and the branched alkylene ether unit (P2) represented by the general formulas (4-1) to (4-4) of the polyalkylene glycol copolymer. The copolymerization ratio of) is a molar ratio of (P1) / (P2), preferably 95/5 to 5/95, more preferably 93/7 to 40/60, and even more preferably 90/10. It is ~ 65/35, and it is more preferable that the linear alkylene ether unit (P1) is rich.
The mole fraction is ^{measured using a 1} H-NMR measuring device using deuterated chloroform as a solvent.

Among the above, particularly preferable polyalkylene glycol (B) is a homopolymer such as polytrimethylene glycol, poly (2-methyl) ethylene glycol, poly (2-ethyl) ethylene glycol, or polytetramethylene glycol, or polytetra. Methylene glycol-polyethylene glycol, polytetramethylene glycol-polytrimethylene glycol, polytetramethylene glycol-poly (2-methyl) ethylene glycol, polytetramethylene glycol-poly (3-methyl) tetramethylene glycol, polytetramethylene glycol- Examples thereof include copolymers of poly (2-ethyl) ethylene glycol, polytetramethylene glycol-polyneopentyl glycol, polyethylene glycol-polytrimethylene glycol, polyethylene glycol-poly (2-methyl) ethylene glycol and the like.

Further, as the polyalkylene glycol (B), even if one end or both ends thereof are sealed with a carboxylic acid or alcohol, the performance development is not affected, and an esterified product or an etherified product can be used in the same manner. Therefore, X and / or Y in the general formulas (1) and (2) are an aliphatic acyl group having 2 to 23 carbon atoms, an alkyl group having 1 to 23 carbon atoms, an aryl group having 6 to 22 carbon atoms, or an aryl group having 6 to 22 carbon atoms. It may be an Aralkyl group of 7 to 23.

Examples of the esterified product include fatty acid esters, and either linear or branched fatty acid esters can be used, and the fatty acids constituting the fatty acid esters may be saturated fatty acids or unsaturated fatty acids. Further, those in which some hydrogen atoms are substituted with a substituent such as a hydroxyl group can also be used.
The fatty acids constituting the fatty acid ester include monovalent or divalent fatty acids having 1 to 23 carbon atoms, for example, monovalent saturated fatty acids, specifically, formic acid, acetic acid, propionic acid, butyric acid, valeric acid, and caproic acid. , Enantic acid, capric acid, capric acid, lauric acid, myristic acid, pentadecic acid, palmitic acid, heptadecic acid, stearic acid, nonadecanic acid, arachidic acid, behenic acid and monovalent unsaturated fatty acids, specifically, Unsaturated fatty acids such as oleic acid, elaidic acid, linoleic acid, linolenic acid, and arachidonic acid, and divalent fatty acids having 10 or more carbon atoms, specifically sebacic acid, undecanoic acid, dodecanedioic acid, and tetradecanedioic acid. , Tapsia acid and decenoic acid, undecenoic acid, dodecene diic acid.
These fatty acids can be used alone or in combination of two or more. The fatty acid also includes a fatty acid having one or more hydroxyl groups in the molecule.

As a preferable specific example of the fatty acid ester of the polyalkylene glycol, in the general formula (1), R is a methyl group, X and Y are an aliphatic acyl group having 18 carbon atoms, polypropylene glycol stearate, R is a methyl group, and X. And polypropylene glycol behenate in which Y is an aliphatic acyl group having 22 carbon atoms. Preferred specific examples of the fatty acid ester of the linear polyalkylene glycol are polyalkylene glycol monopalmitic acid ester, polyalkylene glycol dipalmitic acid ester, polyalkylene glycol monostearic acid ester, polyalkylene glycol distearate, and polyalkylene glycol. Examples thereof include (monopalmitic acid / monostearic acid) ester and polyalkylene glycol behenate.

The alkyl group constituting the alkyl ether of the polyalkylene glycol may be linear or branched, and has, for example, the number of carbon atoms such as a methyl group, an ethyl group, a propyl group, a butyl group, an octyl group, a lauryl group and a stearyl group. Examples thereof include alkyl groups 1 to 23, and examples of such polyalkylene glycols include alkylmethyl ethers, ethyl ethers, butyl ethers, lauryl ethers, and stearyl ethers of polyalkylene glycols.

The aryl group constituting the aryl ether of the polyalkylene glycol is preferably an aryl group having 6 to 22 carbon atoms, more preferably 6 to 12 carbon atoms, and further preferably 6 to 10 carbon atoms, for example, a phenyl group or a tolyl group. Examples thereof include a group and a naphthyl group, and a phenyl group, a tolyl group and the like are preferable. Further, since the end-sealing group exhibits good compatibility with polycarbonate even if it is an aralkyl group, it can exhibit the same action as an aryl group, and the aralkyl group preferably has 7 to 23 carbon atoms. An aralkyl group having 7 to 13 carbon atoms, more preferably 7 to 11 carbon atoms is preferable, and examples thereof include a benzyl group and a phenethyl group, and a benzyl group is particularly preferable.

The number average molecular weight of the polyalkylene glycol (B) is preferably 500 to 5000, more preferably 600 or more, still more preferably 700 or more, still more preferably 4000 or less, still more preferably 3000 or less, and particularly preferably. It is 2000 or less. If it exceeds the upper limit of the above range, the compatibility is lowered, which is not preferable, and if it is less than the lower limit of the above range, gas is likely to be generated during molding, which is not preferable.
The number average molecular weight of the polyalkylene glycol is a number average molecular weight calculated based on the hydroxyl value measured in accordance with JIS K1577.

One type of polyalkylene glycol (B) may be used alone, or two or more types may be used in combination.

As described above, the content of the polyalkylene glycol (B) is 0.1 to 4 parts by mass with respect to 100 parts by mass of the polycarbonate resin (A), but is preferably 0.15 parts by mass or more, more preferably 0.15 parts by mass or more. 0.2 parts by mass or more, more preferably 0.25 parts by mass or more, preferably 3.5 parts by mass or less, more preferably 3 parts by mass or less, still more preferably 2.5 parts by mass or less, especially 2 parts by mass. Below, it is particularly preferable that it is 1.5 parts by mass or less, particularly 1 part by mass or less.

[Polyalkylene glycol (C) having an epoxy group at the end]
The polycarbonate resin composition for optical components of the present invention is characterized by containing a polyalkylene glycol (C) having an epoxy group at the end in addition to the above-mentioned polyalkylene glycol (B) having no epoxy group at the end. And.
The polyalkylene glycol (C) having an epoxy group at the terminal is not limited as long as it is a polyalkylene glycol having an epoxy group at the end, and is mentioned as the polyalkylene glycol (B) having no epoxy group at the end. Preferred examples thereof include polyalkylene glycols in which some or all of the hydroxyl groups present at the ends of the polyalkylene glycol, preferably both ends, are replaced with other epoxy groups.

The polyalkylene glycol of the polyalkylene glycol (C) having an epoxy group at the terminal preferably has an alkylene ether unit having 3 or more carbon atoms in the alkylene group.
Preferred specific examples of the polyalkylene glycol (C) having an epoxy group at the end are mono or diglycidyl products such as polytrimethylene glycol and polytetramethylene glycol, polytetramethylene glycol-polyethylene glycol and polytetramethylene glycol-polytri. Methylene glycol, polytetramethylene glycol-poly (2-methyl) ethylene glycol, polytetramethylene glycol-poly (3-methyl) tetramethylene glycol, polytetramethylene glycol-polyneopentyl glycol, polyethylene glycol-polytrimethylene glycol, Examples thereof include monos such as polyethylene glycol-poly (2-methyl) ethylene glycol or diglycidylated products.

The epoxy equivalent of the polyalkylene glycol (C) having an epoxy group at the terminal is preferably 200 to 1000 g / eq, more preferably 220 to 600 g / eq, and further preferably 250 to 550 g / eq. preferable.
Here, the epoxy equivalent of the polyalkylene glycol (C) having an epoxy group at the terminal is measured by a method based on JIS K7236.

The content of the polyalkylene glycol (C) having an epoxy group at the terminal is 0.005 to 2 parts by mass, preferably 0.01 parts by mass or more, more preferably 0.01 parts by mass with respect to 100 parts by mass of the polycarbonate resin (A). It is 0.015 parts by mass or more, preferably 1.5 parts by mass or less, more preferably 1.2 parts by mass or less, still more preferably 1 part by mass or less, and particularly preferably 0.8 parts by mass or less. If the content of the polyalkylene glycol (C) is less than 0.005 parts by mass, the moisture and heat resistance is deteriorated, and if it exceeds 2 parts by mass, the moisture and heat resistance is deteriorated.

The total content of the polyalkylene glycol (B) having no epoxy group at the terminal and the polyalkylene glycol (C) having an epoxy group at the end is 0.2 with respect to 100 parts by mass of the polycarbonate resin (A). The amount is preferably ~ 3 parts by mass, and more preferably 0.2 to 3 parts by mass.
Further, the mass ratio of the content of the polyalkylene glycol (B) having no epoxy group at the terminal and the polyalkylene glycol (C) having an epoxy group at the end is preferably 30:70 to 99: 1. It is more preferably 50:50 to 99: 1, and even more preferably 60:40 to 99: 1. If the content of the polyalkylene glycol (B) is less than 30%, gas is likely to be generated during extrusion and molding.

[Phosphorus stabilizer (D)]
The polycarbonate resin composition for optical components of the present invention further contains a phosphorus-based stabilizer. By containing a polyalkylene glycol (B) having no epoxy group at the terminal, a polyalkylene glycol (C) having an epoxy group at the end, and a phosphorus-based stabilizer in combination, the hue of the polycarbonate resin composition of the present invention can be obtained. It becomes even better, and the heat discoloration property is further improved.
Any known phosphorus-based stabilizer can be used. Specific examples include phosphoric acid, phosphonic acid, phosphite, phosphinic acid, polyphosphoric acid and other phosphorus oxo acids; acidic sodium pyrophosphate, potassium pyrophosphate, acidic calcium pyrophosphate and other acidic pyrophosphate metal salts; phosphoric acid. Phosphates of Group 1 or Group 2B metals such as potassium, sodium phosphate, cesium phosphate, zinc phosphate; phosphate compounds, phosphite compounds, phosphonite compounds and the like can be mentioned, with phosphite compounds being particularly preferred. By selecting the phosphite compound, a polycarbonate resin composition having higher discoloration resistance and continuous productivity can be obtained.

Here, the phosphite compound is a _{trivalent phosphorus compound represented by the general formula: P (OR) 3} , and R represents a monovalent or divalent organic group.
Examples of such phosphite compounds include triphenylphosphite, tris (monononylphenyl) phosphite, tris (monononyl / dinonyl-phenyl) phosphite, and tris (2,4-di-tert-butylphenyl) phos. Fight, monooctyldiphenylphosphite, dioctylmonophenylphosphite, monodecyldiphenylphosphite, didecylmonophenylphosphite, tridecylphosphite, trilaurylphosphite, tristearylphosphite, distearylpentaerythritol diphosphite, Bis (2,4-di-tert-butyl-4-methylphenyl) pentaerythritol phosphite, bis (2,6-di-tert-butylphenyl) octylphosphite, 2,2-methylenebis (4,6-di) -Tert-Butylphenyl) octylphosphite, tetrakis (2,4-di-tert-butylphenyl) -4,4'-biphenylene-diphosphite, 6- [3- (3-tert-butyl-hydroxy-5-methyl) Phenyl) propoxy] -2,4,8,10-tetra-tert-butyldibenzo [d, f] [1,3,2] -dioxaphosfepine and the like.

Among such phosphite compounds, the aromatic phosphite compound represented by the following formula (5) or (6) is more preferable because the heat-resistant discoloration property of the polycarbonate resin composition of the present invention is effectively enhanced.

(In the formula, R ¹ , R ² and R ³ may be the same or different, respectively, and represent an aryl group having 6 or more and 30 or less carbon atoms.)

(In the formula, R ⁴ and R ⁵ may be the same or different, respectively, and represent an aryl group having 6 or more and 30 or less carbon atoms.)

As the phosphite compound represented by the above formula (5), triphenylphosphine, tris (monononylphenyl) phosphite, tris (2,4-di-tert-butylphenyl) phosphite and the like are preferable, among others. Tris (2,4-di-tert-butylphenyl) phosphite is more preferred. Specific examples of such an organic phosphite compound include "ADEKA STAB 1178" manufactured by ADEKA, "Sumilyzer TNP" manufactured by Sumitomo Chemical, "JP-351" manufactured by Johoku Chemical Industry, and "ADEKA STAB" manufactured by ADEKA. 2112 ”,“ Irgaphos 168 ”manufactured by BASF,“ JP-650 ”manufactured by Johoku Chemical Industry Co., Ltd., and the like.

Examples of the phosphite compound represented by the above formula (6) include bis (2,4-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite and bis (2,6-di-tert-butyl). Those having a pentaerythritol diphosphite structure such as -4-methylphenyl) pentaerythritol diphosphite and bis (2,4-dicumylphenyl) pentaerythritol diphosphite are particularly preferable. Specific examples of such an organic phosphite compound include "ADEKA STAB PEP-24G" and "ADEKA STAB PEP-36" manufactured by ADEKA, and "Doverphos S-9228" manufactured by Doverchemical.

Among the phosphite compounds, the aromatic phosphite compound represented by the above formula (6) is more preferable because it has a more excellent hue.
The phosphorus-based stabilizer may contain one type, or two or more types may be contained in any combination and ratio.

The content of the phosphorus-based stabilizer (D) is 0.005 to 0.5 parts by mass, preferably 0.007 parts by mass or more, and more preferably 0. parts by mass with respect to 100 parts by mass of the polycarbonate resin (A). 008 parts by mass or more, particularly preferably 0.01 parts by mass or more, preferably 0.4 parts by mass or less, more preferably 0.3 parts by mass or less, still more preferably 0.2 parts by mass or less, particularly 0. . 1 part by mass or less. If the content of the phosphorus stabilizer (D) is less than 0.005 parts by mass, the hue and heat-resistant discoloration will be insufficient, and if it exceeds 0.5 parts by mass, the heat-resistant discoloration will only worsen. Not only that, but also the wet and thermal stability is reduced.

[Additives, etc.]
The polycarbonate resin composition for optical components of the present invention includes other additives other than those described above, such as a mold release agent, an antioxidant, an ultraviolet absorber, a fluorescent whitening agent, a pigment, a dye, and other than the polycarbonate resin. It can contain additives such as polymers, flame retardants, impact modifiers, antistatic agents, plasticizers and compatibilizers. These additives may be used alone or in combination of two or more.

[Manufacturing method of polycarbonate resin composition]
The method for producing the polycarbonate resin composition for optical components of the present invention is not limited, and a known method for producing the polycarbonate resin composition can be widely adopted, and the polycarbonate resin (A), polyalkylene glycol (B), (C) and phosphorus can be widely adopted. The system stabilizer (D) and other components to be blended as needed are premixed using various mixers such as a tumbler and a Henschel mixer, and then a Banbury mixer, a roll, a brabender, and a uniaxial kneading extrusion. Examples thereof include a method of melt-kneading with a mixer such as a machine, a twin-screw kneading extruder, or a kneader. The temperature of melt-kneading is not particularly limited, but is usually in the range of 240 to 320 ° C.

The polycarbonate resin composition of the present invention can produce various molded products by molding pellets obtained by pelletizing the above-mentioned polycarbonate resin composition by various molding methods. Further, the resin melt-kneaded by an extruder can be directly molded into a molded product without passing through pellets.

Since the polycarbonate resin composition of the present invention has excellent hue, moisture and heat resistance, excellent fluidity, and high light transmittance, it is suitably used for molding optical parts, particularly thin-walled optical parts, by an injection molding method. Be done. The resin temperature at the time of injection molding is preferably higher than 260 to 300 ° C., which is a temperature generally applied to injection molding of polycarbonate resin, particularly in the case of thin-walled molded products, and is preferably 305. A resin temperature of ~ 400 ° C. is preferable. The resin temperature is more preferably 310 ° C. or higher, further preferably 315 ° C. or higher, particularly preferably 320 ° C. or higher, and even more preferably 390 ° C. or lower. When a conventional polycarbonate resin composition is used, there is a problem that yellowing of the molded product is likely to occur if the resin temperature at the time of molding is raised in order to mold the thin-walled molded product. However, the resin of the present invention has a problem. By using the composition, it becomes possible to produce a molded product having a good hue, particularly a thin-walled optical component, even in the above temperature range. Further, although it has been conventionally practiced to reduce the molecular weight of the polycarbonate resin in order to mold a thin-walled molded product, since the polycarbonate resin composition of the present invention has good fluidity, thin-wall molding can be performed without reducing the molecular weight. , It becomes possible to make a molded product with higher strength.
If it is difficult to measure the resin temperature directly, the resin temperature is grasped as the barrel set temperature.

Here, the thin-walled molded product means a molded product having a plate-shaped portion having a wall thickness of usually 1 mm or less, preferably 0.8 mm or less, and more preferably 0.6 mm or less. Here, the plate-shaped portion may be a flat plate or a curved plate, may have a flat surface, may have irregularities or the like on the surface, and may have an inclined cross section. It may have a wedge-shaped cross section or the like.

Examples of the optical component include components of devices / appliances that directly or indirectly use a light source such as an LED, an organic EL, an incandescent lamp, a fluorescent lamp, and a cathode tube.
The optical component using the polycarbonate resin composition for an optical component of the present invention can be suitably used in the fields of a liquid crystal backlight unit, various display devices, and a lighting device. Examples of such devices include various mobile terminals such as mobile phones, mobile notebooks, netbooks, slate PCs, tablet PCs, smartphones, tablet terminals, cameras, watches, notebook computers, various displays, lighting devices, and the like. Be done.

Hereinafter, the present invention will be described in more detail with reference to Examples. However, the present invention is not construed as being limited to the following examples.
The raw materials and evaluation methods used in the following examples and comparative examples are as follows.

(Examples 1 to 11, Comparative Examples 1 to 3)
[Manufacturing of resin composition pellets]
Each component listed in Table 1 is blended in the proportion (part by mass) shown in Table 2 below, mixed in a tumbler for 20 minutes, and then a single-screw extruder with a vent having a screw diameter of 40 mm (manufactured by Tanabe Plastic Machinery Co., Ltd.). "VS-40") was melt-kneaded at a cylinder temperature of 240 ° C., and pellets were obtained by strand cutting.

[Measurement of hue (YI)]
The obtained pellets are dried at 120 ° C. for 5 to 7 hours with a hot air circulation type dryer, and then by an injection molding machine (“EC100SX-2A” manufactured by Toshiba Machine Co., Ltd.) at a resin temperature of 340 ° C. and a mold temperature of 80 ° C. , A long optical path molded product (300 mm × 7 mm × 4 mm) was molded.
For this long optical path molded product, YI (yellowing degree) was measured with an optical path length of 300 mm. A long optical path spectroscopic transmission chromometer (“ASA 1” manufactured by Nippon Denshoku Kogyo Co., Ltd., C light source, 2 ° field of view) was used for the measurement.

[Evaluation of moisture resistance: Hue (YI) measurement]
The long optical path molded product was kept in a thermostatic chamber at 65 ° C. and a humidity of 85% for 500 hours, and a moisture resistance test was conducted. The YI of the long optical path molded product after the test was measured, and the change in hue (ΔYI) before and after the test was determined.
The above evaluation results are shown in Table 2 below.

Since the polycarbonate resin composition for optical components of the present invention is a polycarbonate resin material having a good hue and excellent moisture and heat resistance, it can be suitably used for various optical components and the like.

Claims (6)

With respect to 100 parts by mass of the polycarbonate resin (A), 0.1 to 4 parts by mass of the polyalkylene glycol (B) having no epoxy group at the end and 0.005 parts of the polyalkylene glycol (C) having an epoxy group at the end. The alkylene group of the polyalkylene glycol (C) containing 0.005 to 0.5 parts by mass of the phosphorus-based stabilizer (D) and having an epoxy group at the terminal has 3 or more carbon atoms. A polycarbonate resin composition for an optical component. The mass ratio of the content of the terminal to the polyalkylene glycol having no epoxy group (B) and a polyalkylene glycol having an epoxy group at the terminal (C) is 30: 70 to 99: according to claim 1 which is 1 Polycarbonate resin composition for optical components. The polycarbonate resin composition for an optical component according to claim 1 or 2 , wherein the polyalkylene glycol (C) having an epoxy group at the terminal has an epoxy equivalent of 200 to 1000 g / eq. The total content of the polyalkylene glycol (B) having no epoxy group at the terminal and the polyalkylene glycol (C) having an epoxy group at the end is 0.2 to 3 with respect to 100 parts by mass of the polycarbonate resin (A). The polycarbonate resin composition for an optical component according to any one of claims 1 to 3 , which is a part by mass. The optical component according to any one of claims 1 to 4, wherein the hue change (ΔYI) of the 300 mm optical path length molded product before and after holding for 500 hours in a constant temperature room at a temperature of 65 ° C. and a humidity of 85% is 1.6 or less. Polycarbonate resin composition. An optical component comprising the polycarbonate resin composition for an optical component according to any one of claims 1 to 5.