JP7441686B2 - Polycarbonate resin composition - Google Patents

Description

The present invention relates to a polycarbonate resin composition, and more particularly to a polycarbonate resin composition that has a high visible light blocking rate and a high transmittance at 960 nm.

Polycarbonate resin is a resin with excellent transparency, heat resistance, mechanical properties, and electrical properties, and is widely used as a material for manufacturing various parts, one example of which is infrared sensors. Infrared sensors use near-infrared light in the vicinity of 850 nm to 1000 nm, but in order to increase the sensitivity of the light receiving section, they require a filter that blocks visible light. When using polycarbonate resin, by adding an infrared absorber, dye and pigment, etc. necessary for blocking visible light to the polycarbonate resin, visible light is blocked and infrared rays are transmitted.

In recent years, infrared sensors have been used for automatic driving control and safe driving control of automobiles, remote control of electronic and electrical equipment, alarm devices, etc., and highly accurate sensor functions are required. Therefore, in order to prevent malfunctions caused by visible light, the infrared transmission filter selectively transmits infrared rays of the desired wavelength used by the sensor, and blocks visible light as close as possible to the wavelength used by the infrared rays, thereby reducing noise. needs to be removed.

As an example of an infrared transmission filter, an infrared transmission filter made by blending an anthraquinone dye having a specific structure with a polycarbonate resin is proposed in Patent Document 1, for example. However, the infrared transmission filter described in Patent Document 1 does not have sufficient shielding properties for visible light at wavelengths close to infrared wavelengths, specifically wavelengths of 700 to 800 nm.

The transmission and blocking performance required of infrared sensors is becoming more and more sophisticated, and recently, near-infrared reflective sensors have become mainstream, It uses the principle that infrared rays are emitted (repelled) when exposed to an object with a . The wavelength used is 900 nm to 1000 nm, and generally a 900 to 960 nm LED is used as a light source.

Japanese Unexamined Patent Publication No. 55-62410

In view of the above-mentioned prior art, an object (object) of the present invention is to provide a polycarbonate resin composition that has a high visible light blocking rate and a high transmittance at 960 nm.

In order to achieve the above-mentioned problems, the present inventor has conducted intensive studies and found that a polycarbonate resin composition containing a dye having a maximum absorption wavelength in the range of 700 to 800 nm has a high visible light blocking rate. It was discovered that the transmittance at 960 nm was high, and the present invention was completed.
That is, the present invention provides the following polycarbonate resin composition.

[1] A polycarbonate resin composition containing 0.005 to 0.45 parts by mass of a dye (B) having a maximum absorption wavelength in the range of 700 to 800 nm, per 100 parts by mass of the polycarbonate resin (A). .
[2] The polycarbonate resin composition according to [1] above, wherein the dye (B) is a quaterrylene dye.
[3] Furthermore, the above [1] or [2] contains 0.01 to 2 parts by mass of a dye (C) having a maximum absorption wavelength of less than 700 nm, based on 100 parts by mass of the polycarbonate resin (A). The polycarbonate resin composition described.
[4] The polycarbonate resin composition according to the above [3], which contains two or more kinds of dyes having different maximum absorption wavelengths as the dye (C).

[5] The polycarbonate resin composition according to any one of [1] to [4] above, which has a transmittance at 800 nm of 5% or less when measured on a molded article having a thickness of 1 mm.
[6] The polycarbonate resin composition according to any one of [1] to [5] above, which has a transmittance at 960 nm of 75% or more when measured on a molded article having a thickness of 1 mm.
[7] Any of the above [1] to [6], in which the transmittance at 800 nm is 5% or less and the transmittance at 960 nm is 75% or more, measured on a molded article molded to a thickness of 1 mm. The polycarbonate resin composition described.

The polycarbonate resin composition of the present invention has a high visible light blocking rate and a high transmittance at 960 nm. It also has excellent thermal stability during molding. Therefore, molded articles made from the polycarbonate resin composition of the present invention can be suitably used as covers for various infrared sensors.

Hereinafter, the present invention will be described in detail by showing embodiments, examples, etc., but the present invention is not limited to the embodiments, examples, etc. shown below.
In the present specification, "~" is used to include the numerical values written before and after it as a lower limit value and an upper limit value.

The polycarbonate resin composition of the present invention contains 0.005 to 0.45 parts by weight of a dye (B) having a maximum absorption wavelength in the range of 700 to 800 nm per 100 parts by weight of the polycarbonate resin (A). It is characterized by

[Polycarbonate resin (A)]
The polycarbonate resin (A) contained in the polycarbonate resin composition of the present invention is not limited in its type, and only one type may be used, or two or more types may be used in combination in any combination and in any ratio. You may.
Polycarbonate resin is a polymer having a basic structure having carbonic acid bonds represented by the general formula: -[-O-X-O-C(=O)-]-. In the above formula, X is generally a hydrocarbon, but X having a hetero atom or hetero bond may be used to impart various properties.

As the polycarbonate resin (A), aromatic polycarbonate resins are particularly preferred. The aromatic polycarbonate resin refers to a polycarbonate resin in which each carbon directly bonded to a carbonate bond is an aromatic carbon. Aromatic polycarbonates are excellent among various polycarbonates in terms of heat resistance, mechanical properties, electrical properties, and the like.

Although there is no specific restriction on the specific type of aromatic polycarbonate resin, examples include aromatic polycarbonate polymers obtained by reacting a dihydroxy compound and 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. Alternatively, a method in which carbon dioxide is used as a carbonate precursor and is reacted with a cyclic ether may also be used. Further, the aromatic polycarbonate polymer may be linear or branched. Furthermore, the aromatic polycarbonate polymer may be a homopolymer consisting of one type of repeating unit, or a copolymer having two or more types of repeating units. At this time, the copolymer can be selected from various copolymerization forms such as a random copolymer and a block copolymer. Note that such an aromatic polycarbonate polymer is usually a thermoplastic resin.

Among the monomers that are raw materials for aromatic polycarbonate resin, examples of aromatic dihydroxy compounds include:
Dihydroxybenzenes such as 1,2-dihydroxybenzene, 1,3-dihydroxybenzene (i.e., resorcinol), and 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 dihydroxynaphthalenes;

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

2,2-bis(4-hydroxyphenyl)propane (i.e., bisphenol A),
1,1-bis(4-hydroxyphenyl)propane,
2,2-bis(3-methyl-4-hydroxyphenyl)propane (i.e., bisphenol C),
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,
Bisphenols containing cardo structure such as 9,9-bis(4-hydroxy-3-methylphenyl)fluorene;

4,4'-dihydroxydiphenyl sulfide,
Dihydroxydiaryl sulfides such as 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfide;

Dihydroxydiaryl sulfoxides such as 4,4'-dihydroxydiphenyl sulfoxide and 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfoxide;

4,4'-dihydroxydiphenyl sulfone,
Dihydroxydiarylsulfones such as 4,4'-dihydroxy-3,3'-dimethyldiphenylsulfone;
etc.

Among these, bis(hydroxyaryl)alkanes are preferred, and bis(4-hydroxyphenyl)alkanes are particularly preferred, and 2,2-bis(4-hydroxyphenyl)propane (i.e. , bisphenol A), or 2,2-bis(3-methyl-4-hydroxyphenyl)propane (ie, bisphenol C).
In addition, one type of aromatic dihydroxy compound may be used, or two or more types may be used in combination in any combination and ratio.

In addition, examples of monomers that are raw materials for aliphatic polycarbonate resins include:
Ethane-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 diol, butane-1,4-diol, pentane-1,5-diol, hexane-1,6-diol, decane-1,10-diol;

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;

Glycols such as ethylene glycol, 2,2'-oxydiethanol (i.e. diethylene glycol), triethylene glycol, propylene glycol, spiroglycol;

1,2-benzenedimethanol, 1,3-benzenedimethanol, 1,4-benzenedimethanol, 1,4-benzenedimethanol, 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- Aralkyl diols such as bis(2-hydroxyethoxy)biphenyl, bisphenol A bis(2-hydroxyethyl) ether, bisphenol S bis(2-hydroxyethyl) ether;

1,2-epoxyethane (i.e. ethylene oxide), 1,2-epoxypropane (i.e. propylene oxide), 1,2-epoxycyclopentane, 1,2-epoxycyclohexane, 1,4-epoxycyclohexane, 1-methyl -Cyclic ethers such as -1,2-epoxycyclohexane, 2,3-epoxynorbornane, and 1,3-epoxypropane; and the like.

Among the monomers used as raw materials for polycarbonate resin, carbonyl halides, carbonate esters, and the like are used as examples of carbonate precursors. In addition, one type of carbonate precursor may be used, or two or more types may be used in combination in any combination and ratio.

Specific examples of carbonyl halides include phosgene; haloformates such as bischloroformates of dihydroxy compounds and monochloroformates of dihydroxy compounds.

Specific examples of carbonate esters include diaryl carbonates such as diphenyl carbonate and ditolyl carbonate; dialkyl carbonates such as dimethyl carbonate and diethyl carbonate; biscarbonates of dihydroxy compounds, monocarbonates of dihydroxy compounds, and cyclic carbonates. Examples include carbonate forms of dihydroxy compounds such as .

The method for producing polycarbonate resin is not particularly limited, and any known method can be employed. Examples include interfacial polymerization, melt transesterification, pyridine method, ring-opening polymerization of cyclic carbonate compounds, and solid phase transesterification of prepolymers.

The molecular weight of the polycarbonate resin (A) is arbitrary and may be appropriately selected and determined, but it is preferably 10,000 to 40,000 in terms of viscosity average molecular weight [Mv]. When the viscosity average molecular weight is less than 10,000, mechanical strength tends to be insufficient, and when the viscosity average molecular weight exceeds 40,000, fluidity tends to be poor and moldability tends to be poor. The viscosity average molecular weight is more preferably 16,000 to 40,000, even more preferably 18,000 to 30,000, particularly 18,500 to 25,000. The molecular weight can be adjusted within this range by known methods such as controlling the amount of a molecular weight regulator as described below.

Here, the viscosity average molecular weight [Mv] is calculated by calculating the intrinsic viscosity [η] (unit: dl/g) at a temperature of 25°C using an Ubbelohde viscometer using methylene chloride as a solvent, and using Schnell's viscosity formula, That is, it means the value calculated from η=1.23×10 ⁻⁴ Mv ^0.83 . Moreover, the intrinsic viscosity [η] is a value calculated by measuring the specific viscosity [ηsp] at each solution concentration [C] (g/dl) and using the following formula.

Other matters regarding polycarbonate resin The terminal hydroxyl group concentration of the polycarbonate resin is arbitrary and may be selected and determined as appropriate, but is usually 1,000 ppm or less, preferably 800 ppm or less, more preferably 600 ppm or less. By doing so, the retention heat stability and color tone of the polycarbonate resin composition can be further improved. Moreover, the lower limit is usually 10 ppm or more, preferably 30 ppm or more, and more preferably 40 ppm or more, especially for polycarbonate resins manufactured by melt transesterification. Thereby, a decrease in molecular weight can be suppressed and the mechanical properties of the polycarbonate resin composition can be further improved.
Note that the unit of the terminal hydroxyl group concentration is the mass of the terminal hydroxyl group expressed in ppm relative to the mass of the polycarbonate resin. The measurement method is colorimetric determination using titanium tetrachloride/acetic acid method (method described in Macromol. Chem. 88 215 (1965)).

Note that the polycarbonate resin (A) is not limited to an embodiment containing only one type of polycarbonate resin, but may be used as a mixture of two or more types of polycarbonate resins that differ in monomer composition, molecular weight, terminal hydroxyl group concentration, etc. Further, it may be used in combination as an alloy (mixture) in which polycarbonate resin is mixed with other thermoplastic resins.

Furthermore, for example, in order to further improve flame retardancy and impact resistance, polycarbonate resin may be copolymerized with an oligomer or polymer having a siloxane structure; copolymers with monomers, oligomers or polymers having a dihydroxyanthraquinone structure for the purpose of improving thermal oxidative stability; Copolymers with oligomers or polymers having an olefinic structure; copolymers with polyester resin oligomers or polymers for the purpose of improving chemical resistance; copolymers mainly composed of polycarbonate resins; 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 1,500 or more, preferably 2,000 or more, and usually 9,500 or less, preferably 9,000 or less. Furthermore, it is preferable that the polycarbonate oligomer contained be 30% by mass or less of the polycarbonate resin (including the polycarbonate oligomer).

Furthermore, 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). Examples of the used products include optical recording media such as optical discs; light guide plates; vehicle transparent members such as automobile window glass, automobile headlamp lenses, and windshields; containers such as water bottles; eyeglass lenses; soundproof walls; Examples include architectural components such as glass windows and corrugated sheets. It is also possible to use nonconforming products, pulverized products obtained from sprues, runners, etc., or pellets obtained by melting them.
However, the recycled polycarbonate resin preferably accounts for 80% by mass or less, more preferably 50% by mass or less, of the polycarbonate resin contained in the polycarbonate resin composition. Recycled polycarbonate resin is highly likely to have undergone deterioration due to thermal deterioration or aging, so if such polycarbonate resin is used in an amount greater than the above range, the hue and mechanical properties may deteriorate. This is because of their gender.

[Dye (B)]
The polycarbonate resin composition of the present invention contains a dye (B) having a maximum absorption wavelength in the range of 700 to 800 nm.

In the present invention, the maximum absorption wavelength of the dye (B) is defined as the maximum absorption wavelength of the absorption curve obtained from the following formula (1) in accordance with JIS K7105.
[Absorbance of polycarbonate resin containing 0.005% by mass of dye (B)] - [Absorbance of polycarbonate resin alone]... (1)
That is, according to the above formula (1), from the absorbance of a flat molded product of polycarbonate resin containing 0.005% by mass of dye (B), the absorbance of a polycarbonate resin of the same shape but not containing dye (B) It is defined as the maximum absorption wavelength of the absorption curve obtained by subtracting the absorbance of a flat molded product of the same thickness. Although it is considered in principle that the maximum absorption wavelength defined in this manner does not change depending on the thickness of the flat test piece used, in the present invention, it is preferable to compare the thickness of the flat test piece using a thickness of 2 mm.
In addition, the maximum absorption wavelength of dye (C) to be described later is also the same as above.
Further, the specific conditions for the method of measuring and determining the maximum absorption wavelength are as described in Examples.

As the dye (B) having a maximum absorption wavelength in the range of 700 to 800 nm, quaterrylene dyes are particularly preferred. Quaterrylene dyes typically have a quaterrylene-3,4:13,14-tetracarboxylic acid diimide structure, and preferred quaterrylene dyes have such a structure.

Quaterylene dyes are also available as commercial products; for example, manufactured by BASF Color & Effects under the trade names "Lumogen IR765" (maximum absorption wavelength: 740-790 nm) and "Lumogen IR788" (maximum absorption wavelength: 760-800 nm). ) etc.

The content of the dye (B) is 0.005 to 0.45 parts by weight based on 100 parts by weight of the polycarbonate resin (A). If the content is less than 0.005 parts by mass, the light blocking rate in the visible light region from 400 to 800 nm will be poor and the transmittance will be high, and if it exceeds 0.45 parts by mass, the transmittance at 960 nm will decrease. In addition, thermal stability deteriorates and gas generation is likely to occur during molding. The content is preferably 0.01 parts by mass or more, more preferably 0.02 parts by mass or more, and preferably 0.3 parts by mass or less, more preferably 0.2 parts by mass or less, especially 0.1 parts by mass or less. , particularly preferably 0.07 parts by mass or less, particularly preferably 0.05 parts by mass or less.

[Dye (C)]
The polycarbonate resin composition of the present invention contains a dye (C) having a maximum absorption wavelength of less than 700 nm together with the dye (B), so that the visible light blocking rate becomes higher and the visible light blocking rate at 960 nm is increased. It is particularly preferred because of its high transmittance.

The dye (C) having a maximum absorption wavelength in a range of less than 700 nm is preferably an organic dye, such as cyanine dye, phthalocyanine dye, naphthalocyanine dye, immonium dye, aminoium dye, quinolium dye, pyrylium dye, or Ni complex dye. , pyrrolopyrrole dyes, copper complex dyes, azo dyes, anthraquinone dyes, diimonium dyes, squarylium dyes, porphyrin dyes, etc. It is preferable to select a dye with a maximum absorption wavelength of less than 700 nm. .

The maximum absorption wavelength of the dye (C) is defined as described above.
The lower limit of the maximum absorption wavelength of the dye (C) is preferably 300 nm, more preferably 350 nm.

The content of the dye (C) is preferably 0.01 to 2 parts by weight based on 100 parts by weight of the polycarbonate resin (A). If the content is less than 0.01 parts by mass, the light blocking rate in the visible light region and 400 to 800 nm will be poor and the transmittance will be high; if the content exceeds 2 parts by mass, the thermal stability will be poor and the transmittance during high temperature molding will be low. In addition, gas generation during molding is likely to occur. The content is more preferably 0.015 parts by mass or more, more preferably 0.02 parts by mass or more, and preferably 1.8 parts by mass or less, more preferably 1.6 parts by mass or less, especially 1.5 parts by mass. Below, it is preferably 1 part by mass or less, particularly preferably 0.5 part by mass or less.

Containing two or more types of dyes with different maximum absorption wavelengths as dyes (C) can reduce the total content of dyes (C) compared to the case of using only one type of dye, which is effective in suppressing gas generation during molding. preferred.

[Phosphorus stabilizer]
The polycarbonate resin composition of the present invention preferably contains a phosphorus stabilizer. Any known phosphorus stabilizer can be used. Specific examples include oxoacids of phosphorus such as phosphoric acid, phosphonic acid, phosphorous acid, phosphinic acid, and polyphosphoric acid; metal salts of acidic pyrophosphate such as sodium acidic pyrophosphate, potassium acidic pyrophosphate, and calcium acidic pyrophosphate; phosphoric acid; Phosphates of Group 1 or Group 2C metals such as potassium, sodium phosphate, cesium phosphate, and zinc phosphate; examples include organic phosphate compounds, organic phosphite compounds, and organic phosphonite compounds; Particularly preferred.

Examples of organic phosphite compounds include triphenyl phosphite, tris (monononylphenyl) phosphite, tris (monononyl/dinonyl phenyl) phosphite, tris (2,4-di-tert-butylphenyl) phosphite, monooctyl Diphenyl phosphite, dioctyl monophenyl phosphite, monodecyl diphenyl phosphite, didecyl monophenyl phosphite, tridecyl phosphite, trilauryl phosphite, tristearyl phosphite, 2,2-methylenebis(4,6-di- Examples include tert-butylphenyl) octyl phosphite. Specific examples of such organic phosphite compounds include, for example, "ADEKA STAB 1178", "ADEKA STAB 2112", "ADEKA STAB HP-10" manufactured by ADEKA, "JP-351" manufactured by Johoku Kagaku Kogyo Co., Ltd. JP-360'', ``JP-3CP'', BASF's ``Irgafoss 168'', etc.
In addition, one type of phosphorus stabilizer may be contained, or two or more types may be contained in any combination and ratio.

The content of the phosphorus stabilizer is usually 3 parts by mass or more, preferably 0.01 parts by mass or more, more preferably 0.03 parts by mass or more, based on 100 parts by mass of the polycarbonate resin (A), and It is usually 1 part by mass or less, preferably 0.7 part by mass or less, more preferably 0.5 part by mass or less. If the content of the phosphorus stabilizer is less than the lower limit of the above range, the thermal stabilizing effect may be insufficient, and if the content of the phosphorus stabilizer exceeds the upper limit of the above range, the effect may be insufficient. may reach a peak and become uneconomical.

[Phenol stabilizer]
It is also preferable that the polycarbonate resin composition of the present invention contains a phenolic stabilizer. Examples of phenolic stabilizers include hindered phenolic antioxidants. Specific examples include pentaerythritol tetrakis [3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl) ) propionate, thiodiethylenebis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], N,N'-hexane-1,6-diylbis[3-(3,5-di- tert-butyl-4-hydroxyphenylpropionamide), 2,4-dimethyl-6-(1-methylpentadecyl)phenol, diethyl[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl ] Methyl]phosphoate, 3,3',3",5,5',5"-hexa-tert-butyl-a,a',a"-(mesitylene-2,4,6-tolyl)tri-p- Cresol, 4,6-bis(octylthiomethyl)-o-cresol, ethylenebis(oxyethylene)bis[3-(5-tert-butyl-4-hydroxy-m-tolyl)propionate], hexamethylenebis[3 -(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], 1,3,5-tris(3,5-di-tert-butyl-4-hydroxybenzyl)-1,3,5- Triazine-2,4,6(1H,3H,5H)-trione,2,6-di-tert-butyl-4-(4,6-bis(octylthio)-1,3,5-triazin-2-ylamino ) phenol, 2-[1-(2-hydroxy-3,5-di-tert-pentylphenyl)ethyl]-4,6-di-tert-pentylphenyl acrylate, and the like.

Among them, pentaerythritol tetrakis [3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] and octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate are preferred. . Specific examples of such phenolic antioxidants include "Irganox 1010" and "Irganox 1076" manufactured by BASF, "ADEKA STAB AO-50" and "ADEKA STAB AO-60" manufactured by ADEKA, etc. can be mentioned.
In addition, one type of phenolic stabilizer may be contained, or two or more types may be contained in any combination and ratio.

The content of the phenolic stabilizer is usually 0.001 parts by mass or more, preferably 0.01 parts by mass or more, and usually 1 part by mass or less, preferably It is 0.5 part by mass or less. If the content of the phenolic stabilizer is less than the lower limit of the above range, the effect as a phenol stabilizer may be insufficient, and the content of the phenol stabilizer exceeds the upper limit of the above range. In this case, the effect may reach a plateau and become uneconomical.

[Release agent]
It is also preferable that the polycarbonate resin composition of the present invention contains a mold release agent.
Examples of the mold release agent include aliphatic carboxylic acids, esters of aliphatic carboxylic acids and alcohols, aliphatic hydrocarbon compounds having a number average molecular weight of 200 to 15,000, and polysiloxane silicone oils.

As aliphatic carboxylic acids, mention may be made, for example, of saturated or unsaturated aliphatic mono-, di- or trivalent carboxylic acids. Here, aliphatic carboxylic acid also includes alicyclic carboxylic acid. Among these, preferred aliphatic carboxylic acids are monovalent or divalent carboxylic acids having 6 to 36 carbon atoms, and aliphatic saturated monovalent carboxylic acids having 6 to 36 carbon atoms are more preferred. Specific examples of such aliphatic carboxylic acids include palmitic acid, stearic acid, caproic acid, capric acid, lauric acid, arachidic acid, behenic acid, lignoceric acid, cerotic acid, melisic acid, tetraliacontanoic acid, montanic acid, and adipine. Examples include acids, azelaic acid, and the like.

As the aliphatic carboxylic acid in the ester of aliphatic carboxylic acid and alcohol, for example, the same aliphatic carboxylic acids as mentioned above can be used. On the other hand, examples of the alcohol include saturated or unsaturated monohydric or polyhydric alcohols. These alcohols may have a substituent such as a fluorine atom or an aryl group. Among these, monohydric or polyhydric saturated alcohols having 30 or less carbon atoms are preferred, and aliphatic saturated monohydric alcohols or aliphatic saturated polyhydric alcohols having 30 or less carbon atoms are more preferred. Note that aliphatic herein also includes alicyclic compounds.

Specific examples of such alcohols include octanol, decanol, dodecanol, stearyl alcohol, behenyl alcohol, ethylene glycol, diethylene glycol, glycerin, pentaerythritol, 2,2-dihydroxyperfluoropropanol, neopentylene glycol, ditrimethylolpropane, dipentaerythritol, and the like. can be mentioned.

Note that the above ester may contain an aliphatic carboxylic acid and/or an alcohol as an impurity. Moreover, the above-mentioned ester may be a pure substance, but may also be a mixture of a plurality of compounds. Furthermore, the aliphatic carboxylic acid and alcohol that combine to form one ester may be used alone or in combination of two or more in any combination and ratio.

Specific examples of esters of aliphatic carboxylic acids and alcohols include beeswax (a mixture containing myricyl palmitate as the main component), stearyl stearate, behenyl behenate, stearyl behenate, glycerin monopalmitate, and glycerin monostearate. ester, glycerin distearate, glycerin tristearate, pentaerythritol monopalmitate, pentaerythritol monostearate, pentaerythritol distearate, pentaerythritol tristearate, pentaerythritol tetrastearate, and the like.

Examples of aliphatic hydrocarbons having a number average molecular weight of 200 to 15,000 include liquid paraffin, paraffin wax, microwax, polyethylene wax, Fischer-Tropsch wax, and α-olefin oligomers having 3 to 12 carbon atoms. Note that the aliphatic hydrocarbons herein also include alicyclic hydrocarbons. Moreover, these hydrocarbons may be partially oxidized. Further, the number average molecular weight is preferably 5,000 or less. The aliphatic hydrocarbon may be a single substance, but even if it is a mixture of various components and molecular weights, it can be used as long as the main component is within the above range.

Among these, paraffin wax, polyethylene wax, or a partial oxide of polyethylene wax is preferred, paraffin wax and polyethylene wax are more preferred, and polyethylene wax is particularly preferred.

In addition, one type of mold release agent may be contained, or two or more types may be contained in any combination and ratio.
The content of the mold release agent is preferably 0.1 parts by mass or more based on 100 parts by mass of the polycarbonate resin (A). If the content of the mold release agent is less than 0.1 parts by mass, the mold release effect may be insufficient. The content of the mold release agent is usually 2 parts by mass or less, preferably 1 part by mass or less.

[Ultraviolet absorber]
It is also preferable that the polycarbonate resin composition of the present invention contains an ultraviolet absorber. Examples of UV absorbers include inorganic UV absorbers such as cerium oxide and zinc oxide; organic compounds such as benzotriazole compounds, benzophenone compounds, salicylate compounds, cyanoacrylate compounds, triazine compounds, oxanilide compounds, malonic acid ester compounds, and hindered amine compounds. Examples include ultraviolet absorbers. Among these, organic ultraviolet absorbers are preferred, and benzotriazole compounds are particularly preferred. By selecting an organic ultraviolet absorber, transparency and mechanical properties can be improved.

Specific examples of benzotriazole compounds include 2-(2'-hydroxy-5'-methylphenyl)benzotriazole, 2-[2'-hydroxy-3',5'-bis(α,α-dimethylbenzyl) ) phenyl]-benzotriazole, 2-(2'-hydroxy-3',5'-di-tert-butyl-phenyl)-benzotriazole, 2-(2'-hydroxy-3'-tert-butyl-5' -methylphenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-3',5'-di-tert-butyl-phenyl)-5-chlorobenzotriazole), 2-(2'-hydroxy-3 ',5'-di-tert-amyl)-benzotriazole, 2-(2'-hydroxy-5'-tert-octylphenyl)benzotriazole, 2,2'-methylenebis[4-(1,1,3, 2-(2'-hydroxy-5'-tert-octylphenyl)benzotriazole, 2,2' -methylenebis[4-(1,1,3,3-tetramethylbutyl)-6-(2H-benzotriazol-2-yl)phenol], particularly 2-(2'-hydroxy-5'-tert- Octylphenyl)benzotriazole is preferred.

When containing an ultraviolet absorber, the content is preferably 0.05 parts by mass or more, more preferably 0.1 parts by mass or more, based on 100 parts by mass of the polycarbonate resin (A), and the upper limit is Preferably it is 1 part by mass or less, more preferably 0.5 part by mass or less. In addition, one type of ultraviolet absorber may be contained, or two or more types may be contained in any combination and ratio.

[Other ingredients]
The polycarbonate resin composition of the present invention may contain other components other than those mentioned above, as necessary, as long as desired physical properties are not significantly impaired. Examples of other components include resins other than those listed above and various resin additives other than those listed above. In addition, one type of other components may be contained, or two or more types may be contained in any combination and ratio.

Other resins Other resins include, for example, thermoplastic polyester resins such as polyethylene terephthalate resin (PET resin), polytrimethylene terephthalate (PTT resin), and polybutylene terephthalate resin (PBT resin);
Polystyrene resin (PS resin), high impact polystyrene resin (HIPS), acrylonitrile-styrene copolymer (AS resin), acrylonitrile-butadiene-styrene copolymer (ABS resin), acrylonitrile-styrene-acrylic rubber copolymer (ASA) styrenic resins such as acrylonitrile-ethylene propylene rubber-styrene copolymer (AES resin);

Polyolefin resins such as polyethylene resin (PE resin), polypropylene resin (PP resin), cyclic cycloolefin resin (COP resin), and cyclic cycloolefin copolymer (COP) resin;
Polyamide resin (PA resin); Polyimide resin (PI resin); Polyetherimide resin (PEI resin); Polyurethane resin (PU resin); Polyphenylene ether resin (PPE resin); Polyphenylene sulfide resin (PPS resin); Polysulfone resin (PSU resin); polymethacrylate resin (PMMA resin); and the like.
In addition, one type of other resin may be contained, or two or more types may be contained in any combination and ratio.

One type of other resin may be contained, or two or more types may be contained in any combination and ratio. However, when containing other resins, the content thereof is preferably 20 parts by mass or less, more preferably 10 parts by mass or less, and further preferably 5 parts by mass or less, and particularly, 100 parts by mass of the polycarbonate resin (A). It is preferably 3 parts by mass or less, particularly 1 part by mass or less.

Resin Additives Examples of resin additives include antistatic agents, fillers, flame retardants, antifogging agents, lubricants, antiblocking agents, fluidity improvers, plasticizers, dispersants, antibacterial agents, and the like.
In addition, one type of resin additive may be contained, or two or more types may be contained in any combination and ratio.

[Manufacture of polycarbonate resin composition]
There are no restrictions on the method for producing the polycarbonate resin composition of the present invention, and any known method for producing a polycarbonate resin composition can be widely adopted. Examples include a method of pre-mixing using various mixers such as or Henschel mixer, and then melt-kneading with a mixer such as a Banbury mixer, roll, Brabender, single-screw kneading extruder, twin-screw kneading extruder, or kneader. Note that the melt-kneading temperature is not particularly limited, but is usually in the range of 240 to 320°C.

The polycarbonate resin composition of the present invention preferably has a transmittance at 800 nm measured on a molded article having a thickness of 1 mm of 5% or less, more preferably 4% or less, still more preferably 3% or less, particularly preferably It is less than 2%.
In addition, the polycarbonate resin composition of the present invention preferably has a transmittance at 960 nm of 75% or more, more preferably 80% or more, still more preferably 83% or more, especially when measured on a molded article having a thickness of 1 mm. is 85% or more.
The polycarbonate resin composition of the present invention has a transmittance of 5% or less at 800 nm measured for a molded article molded to a thickness of 1 mm, and a transmittance at 960 nm measured for a molded article molded to a thickness of 1 mm. It is preferable that the ratio is 75% or more.

[Molded object]
There is no restriction on the method of producing a molded article from the obtained resin composition pellets, and any molding method generally employed for polycarbonate resin compositions can be employed. Examples include injection molding, ultra-high-speed injection molding, injection compression molding, two-color molding, gas-assisted blow molding, molding using an insulated mold, and rapid heating mold. Examples include molding methods, foam molding (including supercritical fluid), insert molding, and IMC (in-mold coating molding) molding methods. Injection molding and injection compression molding are preferred from the viewpoint of ease of molding and productivity.

Molded products made from polycarbonate resin compositions have a high visible light blocking rate and a high transmittance at 960 nm, so they are suitable for use as parts for infrared sensors in the automotive field, OA equipment field, home appliances, electric/electronic fields, etc. For example, monitoring of stores, residences, facilities, railway stations, airports, etc., entry/exit control, and personal authentication; disaster prevention purposes such as road disaster (collapse, etc.) monitoring, dam water volume monitoring, and active volcano monitoring; traffic flow, automatic speed violation Enforcement devices, automatic vehicle license plate reading devices; In the automotive field, driver face orientation recognition, drowsiness prevention devices, night vision, back sonar, lane departure prevention, following distance maintenance, automatic accident avoidance; Electricity for televisions, audio, air conditioning equipment, etc. It can be suitably used for products such as a remote control device for equipment; a counting device for items such as fruits; an optical character reading device using near-infrared rays; and the like.

The present invention will be explained below using examples.
The raw material components used in the Examples and Comparative Examples are shown in Table 1 below.

[Examples 1 to 6, 8-14, Reference Example 7, Comparative Examples 1 to 5]
The above-mentioned components were blended in the proportions shown in Table 2-3 below, mixed in a tumbler for 20 minutes, and then fed to a twin-screw extruder (TEX30α) manufactured by Japan Steel Works, Ltd. equipped with one vent, and the screw rotated. The molten resin composition is melt-kneaded at several 200 rpm, a discharge rate of 20 kg/hour, and a resin temperature of 280 to 300°C (measured value), extruded into a strand, and then rapidly cooled in a water tank and pelletized using a pelletizer to form polycarbonate. Pellets of the resin composition were obtained.

[Measurement of transmittance]
The obtained pellets were dried at 120°C for 5 hours using a hot air circulation dryer, and then molded using an injection molding machine (SE50DUZ manufactured by Sumitomo Heavy Industries, Ltd.) at a resin temperature of 280°C and a mold temperature of 80°C. Under the conditions of a cycle of 40 seconds, a three-step stepped flat test piece with a width of 60 mm x a length of 90 mm and a thickness of 1 mm, 2 mm, and 3 mm was molded.
For thermal stability evaluation, a test piece (hereinafter referred to as "thermal stability evaluation test piece") was obtained in the same manner as above except that the resin temperature was 320° C. and the residence time was 10 minutes.
In accordance with JIS K7105, transmittance was measured using a spectrophotometer ("UV-3600" manufactured by Nippon Denshoku Co., Ltd.) for a 1 mm thick portion of a stepped flat test piece.
Transmittance (unit: %) at 400 nm, 550 nm, 770 nm, 800 nm, and 900 nm is listed in Table 2-3.

Further, regarding the pellets for thermal stability evaluation described above, the transmittance was measured in the same manner as above for a 1 mm thick portion of a stepped flat test piece prepared in the same manner as above. The transmittance (unit: %) at 960 nm is listed in Table 2-3.

The polycarbonate resin composition of the present invention has a high visible light blocking rate and a high transmittance at 960 nm, so it can be widely used as cover parts for various infrared sensors, and has extremely high industrial value.

Claims (4)

For 100 parts by mass of polycarbonate resin (A), 0.02 to 0.07 parts by mass of a dye (B) with a maximum absorption wavelength in the range of 700 to 800 nm , and a dye with a maximum absorption wavelength in the range of 350 nm or more and less than 700 nm. Contains 0.01 to 2 parts by mass of (C) ,
Dye (B) is a quaterrylene dye,
The dye (C) contains two or more types of dyes having different maximum absorption wavelengths, and includes a dye (c1) selected from Disperse Yellow 201, Solvent Red 179, Solvent Violet 13, and Solvent Orange 60; A polycarbonate resin composition containing Solvent Green 3 or Solvent Green 28 as a dye (c2) having a different maximum absorption wavelength . The polycarbonate resin composition according to claim 1, which has a transmittance of 5% or less at 800 nm when measured on a molded article having a thickness of 1 mm. The polycarbonate resin composition according to claim 1 or 2, which has a transmittance of 75% or more at 960 nm when measured on a molded article having a thickness of 1 mm. The polycarbonate resin composition according to any one of claims 1 to 3 , which has a transmittance at 800 nm of 5% or less and a transmittance at 960 nm of 75% or more, measured on a molded article molded to a thickness of 1 mm. .