Compositions, molded articles, and optical filters

Abstract

The present invention provides a composition that exhibits good light transmission in the wavelength range used in infrared sensors and good noise suppression. [Solution] A composition comprising a polycarbonate resin (A) and an infrared absorbent (B), wherein when the total light transmittance of a 2 mm thick composition is measured, the total light transmittance at 940 nm is 88.0% or more, when the total light transmittance of a 2 mm thick composition is measured, the maximum wavelength (x) in the wavelength range of 750 to 860 nm at which the total light transmittance is 1.0% or less is 810 nm or more, and when the total light transmittance of a 2 mm thick composition is measured, the total light transmittance at a wavelength 30 nm greater than the aforementioned wavelength (x) is 35.0% or less.

Description

[Technical Field]

[0001] The present invention relates to a composition, a molded article containing the composition, and an optical filter for an infrared sensor. [Background technology]

[0002] Sensors that use infrared (IR), such as infrared cameras, are sometimes fitted with sensor covers to protect them. Sensor covers are required to transmit light at the wavelength used by the sensor (hereinafter sometimes referred to as the "target wavelength"). Furthermore, since light with wavelengths near the target wavelength can become noise for the sensor, a component that blocks light in the region near the target wavelength (sensor filter) may be used to increase the sensitivity of the sensor. As components that function as sensor covers and sensor filters, materials that block visible light and transmit infrared rays have been developed, and materials such as resins, for example, polycarbonate resins, blended with dyes that absorb infrared rays are known (for example, Patent Document 1). [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 09-3311 [Overview of the Initiative] [Problems that the invention aims to solve]

[0004] In recent years, there has been an increasing demand for improved sensor sensitivity, and there is a need for sensor covers and sensor filters that contribute to improved light transmission at target wavelengths and noise suppression. Regarding the transmittance of light at the target wavelength, some infrared sensors emit infrared light themselves and detect the reflected infrared light. In this case, the infrared light passes through the sensor cover twice—once during irradiation and once during detection—so the amount of light that can be detected relative to the irradiated light is affected by the square of the transmittance. Taking these circumstances into account, even a slight improvement in the transmittance of the target wavelength has become very significant for sensor cover materials in recent years. Furthermore, regarding noise shielding, there is a need for materials that can block as much light as possible near the target wavelength. For example, in recent years, sensors that utilize infrared light in the wavelength range of 900 nm or higher (e.g., 940 nm) have been developed. In such sensors, light between 800 nm and 900 nm can also become noise, so there is a need for sensor filters that can effectively block this wavelength range.

[0005] The present invention has been made in view of the above circumstances and aims to provide a composition that has good light transmittance in the wavelength band used in infrared sensors and good noise shielding, as well as a molded article containing the composition and an optical filter for infrared sensors. [Means for solving the problem]

[0006] As a result of diligent research, the inventors have found that the following invention can solve the above problems, and have completed the present invention. That is, the present invention includes the following embodiments, and also includes embodiments which are any combination of the following embodiments.

[0007] <1> A composition comprising a polycarbonate resin (A) and an infrared absorbent (B), wherein when the total light transmittance of a 2 mm thick composition is measured, the total light transmittance at 940 nm is 88.0% or more, when the total light transmittance of a 2 mm thick composition is measured, the maximum wavelength (x) in the wavelength range of 750 to 860 nm at which the total light transmittance is 1.0% or less is 810 nm or more, and when the total light transmittance of a 2 mm thick composition is measured, the total light transmittance at a wavelength 30 nm greater than the aforementioned wavelength (x) is 35.0% or less. <2> The infrared absorbent (B) has a ratio of (absorbance at 850 nm of the differential absorption curve) / (absorbance at 800 nm of the differential absorption curve) ≥ 0.060. <1> The composition described above. Here, the difference absorption curve is obtained by the following method. 1) Bisphenol A type polycarbonate resin (i) is kneaded at an extrusion temperature of 280°C to produce pellets of the resin (i), and the absorbance of the molded body, which is processed into a 3 mm thick plate shape by injection molding, is measured in the thickness direction to obtain the absorption curve of the resin (i). 2) The resin (i) and the infrared absorbent (B) are kneaded at an extrusion temperature of 280°C to produce pellets of composition (ii) consisting of 100 parts by mass of the resin (i) and 0.005 parts by mass of the infrared absorbent (B). The pellets are then processed into a 3 mm thick plate shape by injection molding, and the absorbance of the molded body is measured in the thickness direction to obtain the absorption curve of composition (ii). 3) The difference absorption curve is obtained by subtracting the absorption curve of composition (ii) from the absorption curve of resin (i). <3> The amount of the infrared absorber (B) is 0.02 parts by mass or more and 0.50 parts by mass or less per 100 parts by mass of the polycarbonate resin (A). <1> or <2> The composition described above. <4> Furthermore, the dye (C) has a maximum absorption wavelength of less than 700 nm, and the amount of the dye (C) is 0.01 parts by mass or more and 1.00 parts by mass or less per 100 parts by mass of the polycarbonate resin (A), <1> from <3> A composition as described in any of the following. <5> The dye (C) contains two or more dyes with different maximum absorption wavelengths. <4> The composition described above. <6> The infrared absorber (B) does not contain a quaterylene-based compound. <1> from <5> A composition as described in any of the following. <7> The infrared absorber (B) contains an anthraquinone-based compound, <1> from <6> A composition as described in any of the following. <8> The resin composition according to any one of <1> to <7>, wherein when the total light transmittance of the composition having a thickness of 2 mm is measured, the total light transmittance at 700 nm is 1.0% or less. <9> The resin composition according to any one of <1> to <8>, wherein when the total light transmittance of the composition having a thickness of 2 mm is measured, the total light transmittance in the wavelength range of 400 nm or more and less than 750 nm is 1.0% or less. <10> A molded body containing the composition according to any one of <1> to <9>. <11> An optical filter for an infrared sensor containing the molded body according to <10>.

Effects of the Invention

[0008] According to the present invention, it is possible to provide a composition having good light transmittance in the wavelength band used in an infrared sensor and good noise blocking property, and a molded body containing the composition and an optical filter for an infrared sensor.

Brief Description of the Drawings

[0009] [Figure 1] The differential absorption curves of infrared absorbers B-1 and B-2 are normalized with the absorbance at 800 nm being 1.0. [Figure 2] FIG. 1 is an enlarged view in the region of wavelengths from 800 to 1000 nm and relative absorbances from 0.0 to 1.0. [Figure 3] Transmission spectra of the total light transmittance of Examples 1 and 2, Comparative Examples 1 to 3, and Reference Example 1 in the range of 300 to 1000 nm. [Figure 4] Transmission spectra of the total light transmittance of Examples 1, Comparative Examples 1 and 2 in the range of 750 to 1000 nm. [Figure 5] Transmission spectra of the total light transmittance of Example 2, Comparative Example 3, and Reference Example 1 in the range of 750 to 1000 nm. [Figure 6] An enlarged view of the transmission spectra of the total light transmittance of Examples 1 and 2, Comparative Examples 1 to 3, and Reference Example 1 in the range of 350 to 750 nm.

Modes for Carrying Out the Invention

[0010] The embodiments of the present invention will be described in detail below, but the description of the constituent elements described below is just one example (representative example) of an embodiment of the present invention, and the present invention is not limited to the following unless its gist is changed. In this specification, when the expression "~" is used, it is used to mean an expression that includes the numerical value or physical property value before and after it.

[0011] <Composition> The present invention relates to a composition comprising a polycarbonate resin (A) and an infrared absorbent (B), wherein when the total light transmittance of a 2 mm thick composition is measured, the total light transmittance at 940 nm is 88.0% or more, when the total light transmittance of a 2 mm thick composition is measured, the maximum wavelength (x) in the wavelength range of 750 to 860 nm at which the total light transmittance is 1.0% or less is 810 nm or more, and when the total light transmittance of a 2 mm thick composition is measured, the total light transmittance at a wavelength 30 nm greater than the aforementioned wavelength (x) is 35.0% or less (hereinafter sometimes referred to as "the composition of the present invention").

[0012] When the composition of the present invention is molded into a 2 mm thick body, the total light transmittance at 940 nm is 88.0% or higher. Therefore, when used as an optical filter for an infrared sensor, the amount of light received by the infrared sensor and the amount of infrared LED light emitted are improved, resulting in improved sensing accuracy. Furthermore, when the molded body has a thickness of 2 mm, the maximum wavelength (x) at which the total light transmittance is 1.0% or less in the wavelength range of 750 to 860 nm is 810 nm or more. When the total light transmittance of the 2 mm thick composition is measured, the total light transmittance at wavelengths 30 nm greater than the aforementioned wavelength (x) is 35.0% or less. Therefore, wavelengths that are not necessary for sensing can be blocked up to the longer wavelength side, and when used as a component for an infrared sensor, it is possible to provide a sensor with good sensing accuracy.

[0013] In one embodiment of the present invention, when the composition of the present invention is used as an optical filter, the wavelength (target wavelength) used by the infrared sensor to which the optical filter is applied is 900 nm or more and 950 nm or less, preferably 910 nm or more, more preferably 920 nm or more, and also preferably 945 nm or less.

[0014] The components constituting the composition of the present invention will be described in detail below. In one embodiment, the present invention is a resin composition. In this embodiment, "composition" in this specification shall be read as "resin composition".

[0015] [Polycarbonate (PC) resin (A)] The polycarbonate resin (A) contained in the composition of the present invention is a polymer having a basic structure with a carbonate bond represented by the formula: -[-OXOC(=O)-]-. In the formula, X is generally a hydrocarbon, but X with heteroatoms or heterobonds introduced may be used to impart various properties.

[0016] Furthermore, polycarbonate resin (A) can be classified into aromatic polycarbonate resin, in which the carbon atoms directly bonded to the carbonate bonds are aromatic carbon atoms, and aliphatic polycarbonate resin, in which the carbon atoms are aliphatic carbon atoms, and either can be used. Among these, aromatic polycarbonate resin is preferred from the viewpoint of heat resistance, mechanical properties, electrical properties, etc.

[0017] There are no specific restrictions on the type of polycarbonate resin (A), but examples include polycarbonate polymers obtained by reacting a dihydroxy compound with a carbonate precursor. In this case, polyhydroxy compounds may also be reacted in addition to the dihydroxy compound and the carbonate precursor. Alternatively, a method may be used in which carbon dioxide is used as the carbonate precursor and reacted with a cyclic ether. Furthermore, the polycarbonate polymer may be linear or branched. In addition, the polycarbonate polymer may be a monopolymer consisting of one type of repeating unit, or a copolymer having two or more types of repeating units. In this case, various copolymerization forms such as random copolymers and block copolymers can be selected. Typically, such polycarbonate polymers are thermoplastic resins.

[0018] Examples of aromatic dihydroxy compounds among the monomers used as raw materials for aromatic polycarbonate resins include: Dihydroxybenzenes such as 1,2-dihydroxybenzene, 1,3-dihydroxybenzene (i.e., resorcinol), and 1,4-dihydroxybenzene;

[0019] Dihydroxybiphenyls such as 2,5-dihydroxybiphenyl, 2,2'-dihydroxybiphenyl, and 4,4'-dihydroxybiphenyl;

[0020] Dihydroxynaphthalene compounds such as 2,2'-dihydroxy-1,1'-binaphthyl, 1,2-dihydroxynaphthalene, 1,3-dihydroxynaphthalene, 2,3-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, 1,7-dihydroxynaphthalene, and 2,7-dihydroxynaphthalene;

[0021] Dihydroxydiaryl ethers such as 2,2'-dihydroxydiphenyl ether, 3,3'-dihydroxydiphenyl ether, 4,4'-dihydroxydiphenyl ether, 4,4'-dihydroxy-3,3'-dimethyldiphenyl ether, 1,4-bis(3-hydroxyphenoxy)benzene, and 1,3-bis(4-hydroxyphenoxy)benzene;

[0022] 2,2-bis(4-hydroxyphenyl)propane (i.e., 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, 1,1-Bis(4-hydroxy-3-methylphenyl)cyclohexane, 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;

[0023] 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;

[0024] Cardo-structure-containing bisphenols such as 9,9-bis(4-hydroxyphenyl)fluorene, 9,9-bis(4-hydroxy-3-methylphenyl)fluorene, and 9,9-bis[4-(2-hydroxyethoxy)phenyl]fluorene;

[0025] Dihydroxydiaryl sulfides such as 4,4'-dihydroxydiphenyl sulfide and 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfide;

[0026] Dihydroxydiaryl sulfoxides such as 4,4'-dihydroxydiphenyl sulfoxide and 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfoxide;

[0027] Dihydroxydiarylsulfones such as 4,4'-dihydroxydiphenylsulfone and 4,4'-dihydroxy-3,3'-dimethyldiphenylsulfone; These are some examples.

[0028] Among these, bis(hydroxyaryl)alkanes and / or bis(alkyl-hydroxyaryl)alkanes are preferred, and among them, bis(4-hydroxyphenyl)alkanes and / or bis(3-alkyl-4-hydroxyaryl)alkanes are preferred, with bis(4-hydroxyphenyl)alkanes being more preferred, and 2,2-bis(4-hydroxyphenyl)propane (i.e., bisphenol A) is particularly preferred from the viewpoint of impact resistance and heat resistance. Note that one aromatic dihydroxy compound may be used, or two or more may be used in any combination and ratio.

[0029] Furthermore, to give an example of monomers that are raw materials for aliphatic polycarbonate resins, Alkanediols such as ethane-1,2-diol, propane-1,2-diol, propane-1,3-diol, 2,2-dimethylpropane-1,3-diol, 2-methyl-2-propylpropane-1,3-diol, butane-1,4-diol, pentane-1,5-diol, hexane-1,6-diol, and decane-1,10-diol;

[0030] Cycloalkanediols such as cyclopentane-1,2-diol, cyclohexane-1,2-diol, cyclohexane-1,4-diol, 1,4-cyclohexanedimethanol, 4-(2-hydroxyethyl)cyclohexanol, and 2,2,4,4-tetramethyl-cyclobutane-1,3-diol;

[0031] Glycols such as ethylene glycol, 2,2'-oxydiethanol (i.e., diethylene glycol), triethylene glycol, propylene glycol, and spiroglycol;

[0032] Aralkyldiols such as 1,2-benzenedimethanol, 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-bis(2-hydroxyethoxy)biphenyl, bisphenol A bis(2-hydroxyethyl) ether, and bisphenol S bis(2-hydroxyethyl) ether;

[0033] Cyclic ethers such as 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-1,2-epoxycyclohexane, 2,3-epoxynorbornane, and 1,3-epoxypropane; These are some examples.

[0034] Among the monomers used as raw materials for polycarbonate resin, examples of carbonate precursors include carbonyl halides and carbonate esters. Note that one type of carbonate precursor may be used, or two or more types may be used in any combination and ratio.

[0035] Examples of carbonyl halides include, specifically, phosgene; bischloroformates of dihydroxy compounds; monochloroformates of dihydroxy compounds; and other haloformates.

[0036] Examples of carbonate esters include diaryl carbonates such as diphenyl carbonate and dityl carbonate; dialkyl carbonates such as dimethyl carbonate and diethyl carbonate; and carbonates of dihydroxy compounds such as biscarbonates, monocarbonates, and cyclic carbonates of dihydroxy compounds.

[0037] The method for producing polycarbonate resin (A) is not particularly limited, and any method can be used. Examples include interfacial polymerization, molten transesterification, pyridine method, ring-opening polymerization of cyclic carbonate compounds, and solid-phase transesterification of prepolymers.

[0038] The polycarbonate resin (A) only needs to have repeating units that constitute a polycarbonate polymer (i.e., a basic structure having a carbonate bond represented by the above formula: -[-OXOC(=O)-]-), and may be a monopolymer or a copolymer. Various copolymerization forms can be selected for the copolymer. Alternatively, it may be a mixture (compound) of two or more types of polycarbonate resins. Specifically, the following (a1) to (a4) can be cited as components of the polycarbonate resin (A). (a1) Monopolymer consisting of one type of repeating unit that constitutes a polycarbonate polymer (a2) Copolymer having two or more repeating units that constitute a polycarbonate polymer (a3) A copolymer having one or more repeating units that constitute a polycarbonate polymer and one or more repeating units that constitute a structure other than a polycarbonate polymer. (a4) A mixture (compound) of two or more polycarbonate polymers (monopolymers and / or copolymers) with different structures and molecular weights.

[0039] The molecular weight of the polycarbonate resin (A) is preferably in the range of 16,000 to 50,000 in viscosity-average molecular weight (Mv), more preferably 18,000 or more, even more preferably 20,000 or more, more preferably 45,000 or less, even more preferably 40,000, and particularly preferably 38,000 or less. If the viscosity-average molecular weight is less than 16,000, the impact resistance of the molded product tends to decrease and cracking may occur, which is undesirable. If it is greater than 50,000, the fluidity will be poor and problems with moldability are likely to occur, which is also undesirable.

[0040] Furthermore, polycarbonate resin (A) may be a mixture of two or more polycarbonate resins with different viscosity-average molecular weights. In this case, if the viscosity-average molecular weight of the mixture falls within the above-mentioned preferred range, polycarbonate resins with viscosity-average molecular weights outside the above-mentioned preferred range may also be mixed in.

[0041] For example, in order to improve the appearance and fluidity of the molded product, the polycarbonate resin (A) may contain a polycarbonate oligomer with a low viscosity-average molecular weight. 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. Furthermore, it is preferable that the amount of polycarbonate oligomer contained is 30% by mass or less of the polycarbonate resin (A) (including the polycarbonate oligomer).

[0042] In this invention, the viscosity-average molecular weight (Mv) of the polycarbonate resin is determined by using methylene chloride as the solvent, calculating the intrinsic viscosity [η] (unit: dl / g) at a temperature of 20°C using an Ubbelohde viscometer, and then using Schnell's viscosity formula, i.e., η = 1.23 × 10⁻¹⁰ -4 Mv 0.83 This refers to the value calculated from [the formula shown]. Furthermore, the intrinsic viscosity [η] is the value calculated by measuring the specific viscosity [ηsp] at each solution concentration [C] (g / dl) and using the following formula.

[0043]

number

[0044] Examples of copolymers having one or more repeating units constituting a polycarbonate polymer and one or more repeating units constituting a structure other than a polycarbonate polymer include copolymers of a polycarbonate polymer with monomers, oligomers, or polymers that can form thermoplastic polymers other than polycarbonate polymers. For example, a copolymer of a polycarbonate polymer with an oligomer or polymer having a siloxane structure for the purpose of further enhancing flame retardancy and impact resistance; a copolymer of a polycarbonate polymer with a monomer, oligomer, or polymer having a phosphorus atom for the purpose of further improving thermal oxidation stability and flame retardancy; a copolymer of a polycarbonate polymer with a monomer, oligomer, or polymer having a dihydroxyanthraquinone structure for the purpose of improving thermal oxidation stability; a copolymer of a polycarbonate polymer with an oligomer or polymer having an olefin-based structure such as polystyrene for the purpose of improving optical properties; a copolymer of a polycarbonate polymer with a polyester resin oligomer or polymer for the purpose of improving chemical resistance; and so on.

[0045] Furthermore, when the polycarbonate resin (A) contains repeating units that constitute a structure other than the polycarbonate polymer, the polycarbonate resin (A) is preferably a copolymer mainly composed of the polycarbonate polymer, and the proportion of the polycarbonate polymer in the polycarbonate resin (A) is preferably 50 mol% or more, more preferably 60 mol% or more, even more preferably 70 mol% or more, particularly preferably 80 mol% or more, and most preferably 90 mol% or more.

[0046] Furthermore, the polycarbonate resin (A) may be not only virgin raw material but also polycarbonate resin recycled from used products (so-called material-recycled polycarbonate resin). However, it is preferable that the recycled polycarbonate resin accounts for 80% by mass or less of the polycarbonate resin (A), and more preferably 50% by mass or less. This is because recycled polycarbonate resin is highly likely to have undergone degradation such as thermal degradation and aging degradation, and using more of such polycarbonate resin than the above range may reduce the hue and mechanical properties.

[0047] The content of polycarbonate resin (A) in the composition of the present invention is preferably 70% by mass or more, more preferably 80% by mass or more, and even more preferably 90% by mass or more. The upper limit is not particularly limited as long as the requirements of the present invention are met, and for example, all components except the infrared absorber (B) may be the polycarbonate resin (A), and the proportion may be, for example, 99.5999% by mass or less. Generally, when the content of polycarbonate resin (A) in the composition of the present invention is above the lower limit, it is easier to obtain a composition with good mechanical strength, transparency, or both.

[0048] [Infrared Visual Agent (B)] The composition of the present invention comprises an infrared absorbent (B). In one embodiment, the infrared absorbent (B) is a compound having a maximum absorption wavelength in the range of 700 nm to 800 nm.

[0049] The infrared absorbent (B) included in the composition of the present invention is preferably selected such that (absorbance at 850 nm of the differential absorption curve) / (absorbance at 800 nm of the differential absorption curve) ≥ 0.060. 850 It may be written as follows: ) The absorbance at 800 nm of the differential absorption curve (hereinafter, △A 800 It may be written as follows: ) the value divided by (△A 850 / △A 800It is preferable to select an infrared absorber (B) of 0.060 or more because the blocking rate of wavelengths on the long wavelength side that are unnecessary for sensing can be improved. The ΔA 850 / ΔA 800 is more preferably 0.080 or more, further preferably 0.10 or more, particularly preferably 0.12 or more, and extremely preferably 0.15 or more. The ΔA 850 / ΔA 800 has an upper limit of, for example, 0.50 or less, 0.40 or less, 0.30 or less, or 0.25 or less. Such an infrared absorber (B) may be selected from commercially available products.

[0050] Here, the differential absorption curve is obtained by the following method. 1) At an extrusion temperature of 280°C, knead the bisphenol A type polycarbonate resin (i) to produce pellets of the resin (i), and measure the absorption curve in the thickness direction of a molded body processed into a plate shape with a thickness of 3 mm by injection molding. 2) At an extrusion temperature of 280°C, knead the resin (i) and the infrared absorber (B) to produce pellets of a composition (ii) composed of 100 parts by mass of the resin (i) and 0.005 parts by mass of the infrared absorber (B), and obtain an absorption curve measured in the thickness direction of a molded body processed into a plate shape with a thickness of 3 mm by injection molding. 3) Subtract the absorption curve of the composition (ii) from the absorption curve of the resin (i) to obtain the differential absorption curve. That is, subtract the absorbance at each wavelength of the absorption curve of the composition (ii) from the absorbance at each wavelength of the absorption curve of the resin (i), plot the difference in absorbance at each wavelength on the vertical axis with the wavelength on the horizontal axis, and obtain the differential absorption curve. The absorbance at each wavelength of the differential absorption curve is the value on the vertical axis. For example, the absorbance at 850 nm of the differential absorption curve is the value on the vertical axis at 850 nm of the differential absorption curve.

[0051] In one embodiment, the infrared absorber (B) has an absorbance of 0.10 or less, and more preferably 0.05 or less, in the wavelength range of 900 nm to 1000 nm of the differential absorption curve. It is preferable that the absorbance in the wavelength range of 900 nm to 1000 nm of the differential absorption curve is below the above upper limit, as this improves the transmittance in the wavelength range used for sensing beyond 900 nm.

[0052] The infrared absorber (B) may be a mixture of one or more types in any combination and ratio.

[0053] The infrared absorber (B) is the aforementioned ΔA 850 / △A 800 Any infrared absorber with a value of 0.060 or higher is acceptable, regardless of its type or structure, but it may include, for example, anthraquinone-based compounds.

[0054] In one embodiment, the infrared absorber (B) may contain a quaterylene-based compound of 0.020% by mass or less. In this embodiment, the quaterylene-based compound content is preferably 0.015% by mass or less, and more preferably 0.010% by mass or less. Furthermore, the infrared absorber (B) may not contain a quaterylene-based compound.

[0055] In the composition of the present invention, the content of the infrared absorbent (B) is preferably 0.02 to 0.50 parts by mass per 100 parts by mass of the polycarbonate resin (A). More preferably, the content of the infrared absorbent (B) is 0.03 parts by mass or more, and even more preferably 0.05 parts by mass or more, per 100 parts by mass of the polycarbonate resin (A). Furthermore, the content of the infrared absorbent (B) is more preferably 0.40 parts by mass or less, even more preferably 0.30 parts by mass or less, and particularly preferably 0.20 parts by mass or less, per 100 parts by mass of the polycarbonate resin (A). When the content of the infrared absorbent (B) is above the lower limit, near-infrared rays around 800 nm can be blocked well, and when the content of the infrared absorbent (B) is below the upper limit, the transmittance of target wavelength bands such as 900 nm or more used for sensing can be made good.

[0056] [Other ingredients] The composition of the present invention may contain resins other than polycarbonate resin (A) and other additives other than infrared absorber (B), to the extent that the objectives of the present invention can be achieved.

[0057] Examples of resins other than polycarbonate resin (A) include thermoplastic resins such as polystyrene and polyester. These other resins may be blended one or more in any combination and ratio.

[0058] Other additives may include, for example, stabilizers, release agents, UV absorbers, antioxidants, fluorescent whitening agents, pigments, dyes, flame retardants, impact modifiers, antistatic agents, plasticizers, and compatibilizers. These additives may be blended individually or in any combination and ratio.

[0059] [Dye (C)] The composition of the present invention preferably contains a dye (C) having a maximum absorption wavelength of less than 700 nm. By including dye (C), the transmittance of visible light can be reduced.

[0060] The maximum absorption wavelength of dye (C) is defined as the maximum absorption wavelength in the differential absorption curve obtained by subtracting the absorption curve of resin (i) from the absorption curve of composition (iii), which is made by producing a molded article of bisphenol A type polycarbonate resin (i) and composition (iii) consisting of 100 parts by mass of bisphenol A type polycarbonate resin (i) and 0.005 parts by mass of dye (C) in the same manner as the method for obtaining the differential absorption curve of infrared absorber (B) described above.

[0061] Furthermore, as for the dye (C), one with a maximum absorption wavelength of 400 nm or more is preferred, and one with a maximum absorption wavelength of 420 nm or more is more preferred.

[0062] As the dye (C) with a maximum absorption wavelength of less than 700 nm, organic dyes are preferred. For example, dyes with a maximum absorption wavelength of less than 700 nm can be selected from among anthraquinone dyes, methine dyes, and perinone dyes.

[0063] Specifically, dyes such as CISolvent Violet 36, CISolvent Blue 97, CISolvent Green 3, CISolvent Green 5, CISolvent Green 28, CISolvent Yellow 16, CISolvent Yellow 201, CISolvent Red 111, CISolvent Red 179, CISolvent Orange 60, and CISolvent Red 52 are preferably used.

[0064] Furthermore, the content of dye (C) is preferably 0.01 to 1.00 parts by mass per 100 parts by mass of polycarbonate resin (A). More preferably, the content of dye (C) is 0.02 parts by mass or more, even more preferably 0.05 parts by mass or more, and particularly preferably 0.08 parts by mass or more, per 100 parts by mass of polycarbonate resin (A). Furthermore, the content of dye (C) is more preferably 0.70 parts by mass or less, and even more preferably 0.50 parts by mass or less, per 100 parts by mass of polycarbonate resin (A). A dye (C) content above the lower limit can reduce the transmittance of visible light, and a dye (C) content below the upper limit can reduce the amount of gas generated in the mold during molding, thereby suppressing mold contamination, which is preferable.

[0065] The dye (C) may be one type or two or more types, but from the viewpoint of blocking light in the visible light region over as wide a wavelength range as possible, it is preferable to include two or more types with different maximum wavelengths.

[0066] (Stabilizer) The composition of the present invention may contain a stabilizer. Examples of stabilizers include phosphorus-based stabilizers, phenol-based stabilizers, sulfur-based stabilizers, and the like. Among these, phosphorus-based stabilizers and / or phenol-based stabilizers are preferred.

[0067] (Phosphorus stabilizer) The composition of the present invention may contain a phosphorus-based stabilizer. The inclusion of a phosphorus-based stabilizer tends to improve the heat resistance and discoloration properties of the composition of the present invention. Any known phosphorus-based stabilizer can be used. Specific examples include phosphorus oxoacids such as phosphoric acid, phosphonic acid, phosphinic acid, phosphinic acid, and polyphosphate; acidic pyrophosphate metal salts such as sodium acidic pyrophosphate, potassium acidic pyrophosphate, and calcium acidic pyrophosphate; phosphates of Group 1 or Group 2B metals such as potassium phosphate, sodium phosphate, cesium phosphate, and zinc phosphate; phosphate compounds, phosphite compounds, and phosphonite compounds. Among these, phosphate compounds or phosphite compounds are particularly preferred from the viewpoint of obtaining a composition with high discoloration resistance and continuous productivity.

[0068] Here, the phosphate compound is a pentavalent phosphorus compound represented by the general formula O=P(OR)3, where R represents a monovalent or divalent organic group. When the phosphorus-based stabilizer contains a phosphate compound, each of the three organic groups R may independently be a substituted or unsubstituted aliphatic hydrocarbon group or an aromatic hydrocarbon group, the aliphatic hydrocarbon group may be saturated or unsaturated, and each of the three organic groups R may independently have some carbon atoms substituted with heteroatoms such as oxygen, nitrogen, sulfur, or phosphorus. The number of carbon atoms in the three organic groups R is usually 2 or more, preferably 3 or more, more preferably 5 or more, and usually 20 or less, preferably 15 or less, more preferably 12 or less. Preferably, one or more of the three organic groups R are aromatic hydrocarbon groups, more preferably two or more, and even more preferably all three are aromatic hydrocarbon groups. If one or more of the three organic groups R include an aromatic hydrocarbon group, the aromatic hydrocarbon group preferably includes one or more selected from the group consisting of a tert-butylphenyl group, a cresyl group, and a phenyl group. In a particularly preferred embodiment, the phosphate compound comprises one or more selected from the group consisting of tris(4-tert-butylphenyl) phosphate, tris(2,4-di-tert-butylphenyl) phosphate, tricresyl phosphate, and triphenyl phosphate, and more preferably comprises either tris(4-tert-butylphenyl) phosphate or tris(2,4-di-tert-butylphenyl) phosphate.

[0069] Furthermore, the phosphite compound is a trivalent phosphorus compound represented by the general formula: P(OR)3, where R represents a monovalent or divalent organic group. The preferred embodiment of R is the same as that of the phosphate compound described above. Examples of such phosphite compounds include triphenyl phosphite, tris(mononylphenyl) phosphite, tris(mononyl / dinonylphenyl) phosphite, tris(2,4-di-tert-butylphenyl) phosphite, monooctyldiphenyl phosphite, dioctylmonophenyl phosphite, monodecyldiphenyl phosphite, didecylmonophenyl phosphite, tridecyl phosphite, trilauryl phosphite, tristearyl phosphite, distearylpentaerythritol diphosphite, bis(2,4- Examples include di-tert-butyl-4-methylphenyl)pentaerythritol phosphite, bis(2,6-di-tert-butylphenyl)octyl phosphite, 2,2-methylenebis(4,6-di-tert-butylphenyl)octyl phosphite, tetrakis(2,4-di-tert-butylphenyl)-4,4'-biphenylene-diphosphite, and 6-[3-(3-tert-butyl-hydroxy-5-methylphenyl)propoxy]-2,4,8,10-tetra-tert-butyldibenzo[d,f][1,3,2]-dioxaphosfepine.

[0070] Among such phosphite compounds, aromatic phosphite compounds represented by the following general formula (II) or (III) are more preferred because they tend to effectively enhance the heat resistance and color change properties of the composition of the present invention.

[0071] [ka]

[0072] In formula (II), R 20 , R 21 and R 22 These may be the same or different, and each represents an aryl group with 6 to 30 carbon atoms.

[0073] [ka]

[0074] In formula (III), R 23 and R 24 These may be the same or different, and each represents an aryl group with 6 to 30 carbon atoms.

[0075] Among the phosphite compounds represented by the above formula (II), triphenyl phosphite, tris(mononylphenyl) phosphite, and tris(2,4-di-tert-butylphenyl) phosphite are preferred, with tris(2,4-di-tert-butylphenyl) phosphite being more preferred.

[0076] Among the phosphite compounds represented by the above formula (III), those having a pentaerythritol diphosphite structure, such as bis(2,4-di-tert-butyl-4-methylphenyl)pentaerythritol diphosphite, bis(2,6-di-tert-butyl-4-methylphenyl)pentaerythritol diphosphite, and bis(2,4-dicumylphenyl)pentaerythritol diphosphite, are particularly preferred.

[0077] Specifically, examples include "ADEKA Stab® 1178" and "ADEKA Stab® 2112" from ADEKA Corporation, "JP-351," "JP-360," and "JP-3CP" from Johoku Chemical Industry Co., Ltd., and "Irgafos® 168" from BASF Corporation.

[0078] When a phosphorus-based stabilizer is included, the content of the phosphorus-based stabilizer in the composition is preferably 0.01 to 0.5% by mass. More preferably 0.02% by mass or more, even more preferably 0.03% by mass or more, even more preferably 0.4% by mass or less, even more preferably 0.3% by mass or less, and even more preferably 0.2% by mass or less. If the content of the phosphorus-based stabilizer is less than 0.01% by mass, the heat resistance to discoloration may be insufficient, and if it exceeds 0.5% by mass, it will be an excessive amount and tend to worsen economic efficiency. Note that one type of phosphorus-based stabilizer may be included, or two or more types may be included in any combination and ratio.

[0079] (Phenol-based stabilizers) The composition of the present invention may contain 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- Examples include triyl)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-triazine-2-ylamino)phenol, and 2-[1-(2-hydroxy-3,5-di-tert-pentylphenyl)ethyl]-4,6-di-tert-pentylphenyl acrylate.

[0080] Among these, 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, for example, BASF's "Irganox® 1010" and "Irganox® 1076," and ADEKA's "ADEKA Stab® AO-50" and "ADEKA Stab® AO-60."

[0081] When a phenolic stabilizer is included, the content of the phenolic stabilizer in the composition is preferably 0.01 to 0.5% by mass. More preferably 0.03% by mass or more, even more preferably 0.05% by mass or more, even more preferably 0.07% by mass or more, and even more preferably 0.4% by mass or less, even more preferably 0.3% by mass or less, even more preferably 0.2% by mass or less, and particularly preferably 0.15% by mass or less. By having a phenolic stabilizer content above the lower limit, good antioxidant function can be obtained, and by having a content below the upper limit, a decrease in economic efficiency due to the addition of an excessive amount can be prevented. Note that one type of phenolic stabilizer may be included, or two or more types may be included in any combination and ratio.

[0082] (Release agent) The composition of the present invention may contain a release agent. Examples of release agents include aliphatic carboxylic acids, esters of aliphatic carboxylic acids and alcohols, aliphatic hydrocarbon compounds with a number average molecular weight of 200 to 15,000, and polysiloxane-based silicone oils.

[0083] Examples of aliphatic carboxylic acids include saturated or unsaturated aliphatic monovalent, divalent, or trivalent carboxylic acids. Here, aliphatic carboxylic acids also include alicyclic carboxylic acids. Among these, preferred aliphatic carboxylic acids are monovalent or divalent carboxylic acids having 6 to 36 carbon atoms, and more preferably aliphatic saturated monovalent carboxylic acids having 6 to 36 carbon atoms. 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, melissic acid, tetrariacontanoic acid, montanic acid, adipic acid, and azelaic acid.

[0084] As the aliphatic carboxylic acid in the ester of an aliphatic carboxylic acid and an alcohol, for example, the same aliphatic carboxylic acid as described above can be used. On the other hand, as the alcohol, for example, saturated or unsaturated monohydric or polyhydric alcohols can be used. These alcohols may have substituents such as fluorine atoms or aryl groups. Among these, monohydric or polyhydric saturated alcohols with 30 or fewer carbon atoms are preferred, and aliphatic saturated monohydric alcohols or aliphatic saturated polyhydric alcohols with 30 or fewer carbon atoms are more preferred. Here, aliphatic 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, and dipentaerythritol.

[0085] Furthermore, the above esters may contain aliphatic carboxylic acids and / or alcohols as impurities. Also, the above esters may be pure substances or mixtures of multiple compounds. Moreover, the aliphatic carboxylic acids and alcohols that combine to form a single ester may be used individually, or two or more may be used in any combination and ratio.

[0086] Specific examples of esters of aliphatic carboxylic acids and alcohols include beeswax (a mixture mainly composed of myricyl palmitate), stearyl stearate, behenyl behenate, stearyl behenate, glycerin monopalmitate, glycerin monostearate, glycerin distearate, glycerin tristearate, pentaerythritol monopalmitate, pentaerythritol monostearate, pentaerythritol distearate, pentaerythritol tristearate, and pentaerythritol tetrastearate.

[0087] Examples of aliphatic hydrocarbons with 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 alicyclic hydrocarbons are also included as aliphatic hydrocarbons. These hydrocarbons may also be partially oxidized. The number-average molecular weight is preferably 5,000 or less. The aliphatic hydrocarbon may be a single substance, but a mixture of substances with various components and molecular weights can also be used as long as the main component is within the above range.

[0088] Among these, paraffin wax, polyethylene wax, or partially oxided polyethylene wax are preferred, paraffin wax and polyethylene wax are more preferred, and polyethylene wax is particularly preferred.

[0089] The release agent content is preferably 0.1 parts by mass or more per 100 parts by mass of polycarbonate resin (A). If the release agent content is less than 0.1 parts by mass, the release effect may be insufficient. The release agent content is usually 2 parts by mass or less, preferably 1 part by mass or less. If the release agent content exceeds 2 parts by mass, gas is more likely to be generated during molding, which tends to contaminate the mold. The release agent may contain one type, or two or more types may be contained in any combination and ratio.

[0090] [UV absorber] The composition of the present invention may contain an ultraviolet absorber. Examples of ultraviolet absorbers include inorganic ultraviolet absorbers such as cerium oxide and zinc oxide; and organic ultraviolet absorbers such as benzotriazole compounds, benzophenone compounds, salicylate compounds, cyanoacrylate compounds, triazine compounds, oxanilide compounds, malonic acid ester compounds, and hindered amine compounds. Of these, organic ultraviolet absorbers are preferred, and benzotriazole compounds are more preferred. By selecting an organic ultraviolet absorber, good mechanical properties are obtained.

[0091] Specific examples of benzotriazole compounds include, for example, 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, and 2-(2'-hydroxy-3',5'-di-tert-amyl)-benzotriazole. Examples include azoles, 2-(2'-hydroxy-5'-tert-octylphenyl)benzotriazole, and 2,2'-methylenebis[4-(1,1,3,3-tetramethylbutyl)-6-(2H-benzotriazole-2-yl)phenol], among which 2,2'-methylenebis[4-(1,1,3,3-tetramethylbutyl)-6-(2H-benzotriazole-2-yl)phenol] and 2-(2'-hydroxy-5'-tert-octylphenyl)benzotriazole are preferred, with 2,2'-methylenebis[4-(1,1,3,3-tetramethylbutyl)-6-(2H-benzotriazole-2-yl)phenol] being particularly preferred. Examples of compounds other than benzotriazole compounds include, for example, 2,2'-dihydroxy-4-methoxybenzophenone and 2,2'-dihydroxy-4,4'-methoxybenzophenone as benzophenone compounds, and for example, 2,4,6-tris(2-hydroxy-4-hexyloxy-3-methylphenyl)-1,3,5-triazine as a triazine compound.

[0092] If an ultraviolet absorber is included, the amount is preferably 0.05 parts by mass or more, more preferably 0.1 parts by mass or more, per 100 parts by mass of polycarbonate resin (A), and the upper limit is preferably 1 part by mass or less, more preferably 0.5 parts by mass or less. Note that one type of ultraviolet absorber may be included, or two or more types may be included in any combination and ratio.

[0093] In one embodiment, when the target wavelength is 900 nm or more and 950 nm or less, the composition of the present invention preferably contains 0.50% by mass or less, more preferably 0.20% by mass or less, and even more preferably none, dyes with a maximum absorption wavelength greater than 800 nm, in order to transmit light of the target wavelength well. For example, dyes such as condensed polycyclic dyes, phthalocyanine dyes, copper-containing phthalocyanine dyes, nickel complex dyes, and polymethine dyes, which have a maximum absorption wavelength greater than 800 nm, preferably contain the above amounts.

[0094] <Total light transmittance of the composition> The composition of the present invention, when the total light transmittance of a 2 mm thick composition is measured, has a total light transmittance of 88.0% or more at 940 nm, and in the wavelength range of 750 to 860 nm, the maximum wavelength (x) at which the transmittance is 1.0% or less is 810 nm or more, and when the total light transmittance of the 2 mm thick composition is measured, the total light transmittance at a wavelength 30 nm greater than the aforementioned wavelength (x) is 35.0% or less.

[0095] The total light transmittance can be measured using a spectrophotometer with an integrating sphere, with a flat molded product of the composition of the present invention, molded to a thickness of 2 mm, as the measurement sample. The total light transmittance can be measured, for example, by a method conforming to JIS-K7361-1, and an example of specific conditions for the measurement method is as described in the examples.

[0096] When the total light transmittance of the composition of the present invention with a thickness of 2 mm is measured, the total light transmittance at 940 nm is 88.0% or higher, preferably 88.5% or higher, and more preferably 89.0% or higher.

[0097] There is no particular upper limit to the total light transmittance at a wavelength of 940 nm of a 2 mm thick composition of the present invention; a higher value is preferable. However, in one embodiment, when the total light transmittance of a 2 mm thick composition of the present invention is measured, the total light transmittance at a wavelength of 940 nm can be 88.0-95.0%, 88.0-94.0%, 88.5-93.0%, 88.5-92.0%, or 89.0-91.0%.

[0098] When the total light transmittance of the composition of the present invention with a thickness of 2 mm is measured, the maximum wavelength (x) at which the transmittance is 1.0% or less in the wavelength range of 750 to 860 nm is 810 nm or higher. For example, when applying the composition of the present invention to an optical filter of an infrared sensor that uses infrared light in the 900-950 nm range, from the viewpoint of blocking unwanted light up to the long wavelength region as close as possible to the target wavelength, the wavelength (x) is preferably 812 nm or higher, and more preferably 815 nm or higher. On the other hand, if the wavelength (x) is adjusted too far towards the long wavelength side, the transmittance of the target wavelength may decrease. Therefore, when the target wavelength is 900-950 nm, from the viewpoint of maintaining good transmittance of the target wavelength, the wavelength (x) is preferably 850 nm or lower, and more preferably 840 nm or lower.

[0099] Furthermore, when the composition of the present invention is applied to an optical filter or the like of an infrared sensor that utilizes infrared light in the 900-950 nm range, the composition of the present invention has low transmittance of light in the wavelength band near the target wavelength, specifically in the wavelength band of 800 nm to less than 900 nm. This allows it to block light that is closer to the target wavelength than light in the 700-800 nm range and is more likely to cause noise problems, thus enabling sensing with less noise. From the viewpoint of obtaining such effects, when the total light transmittance of the composition of the present invention with a thickness of 2 mm is measured, it is preferable that the total light transmittance at a wavelength 30 nm greater than the aforementioned wavelength (x) be 35.0% or less, more preferably 32.0% or less, even more preferably 30.0% or less, and particularly preferably 28.0% or less.

[0100] In one embodiment, when the total light transmittance of a composition of the present invention with a thickness of 2 mm is measured, the total light transmittance at a wavelength 30 nm greater than the aforementioned wavelength (x) can be 5.0 to 35.0%, 8.0 to 32.0%, 10.0 to 30.0%, or 15.0 to 28.0%. However, the lower limit of the total light transmittance at a wavelength 30 nm greater than the aforementioned wavelength (x) is not particularly limited, and a lower value is preferable.

[0101] In one embodiment, when the total light transmittance of a composition of the present invention with a thickness of 2 mm is measured, the total light transmittance at a wavelength of 850 nm is preferably 40.0% or less, more preferably 38.0% or less, even more preferably 35.0% or less, and particularly preferably 33.0% or less. Since the transmittance at the above wavelength of 850 nm is below the above upper limit, noise in wavelength bands that are particularly close to the wavelength range used for sensing and are difficult to eliminate as noise can be effectively blocked, and when the composition of the present invention is used as a component for a sensor, a sensor with good sensing accuracy can be provided.

[0102] In one embodiment, when the total light transmittance of a composition of the present invention with a thickness of 2 mm is measured, the total light transmittance at a wavelength of 850 nm can be 5.0 to 40.0%, 6.0 to 38.0%, 8.0 to 35.0%, or 10.0 to 33.0%, but there is no particular lower limit to the total light transmittance at a wavelength of 850 nm; the lower the better.

[0103] In one embodiment, when the total light transmittance of a composition of the present invention with a thickness of 2 mm is measured, the total light transmittance increases from the aforementioned wavelength (x) to 900 nm, and the total light transmittance at a wavelength of 900 nm can be 70.0% or more, or 70.0 to 87.5%, or 75.0 to 85.0%.

[0104] In one embodiment, when the total light transmittance of a 2 mm thick composition of the present invention is measured, the total light transmittance at a wavelength of 700 nm is 1.0% or less. Preferably, the total light transmittance is 0.8% or less, and more preferably 0.5% or less. Since the total light transmittance is below the above upper limit, it can be suitably used in sensor covers with a design that does not make the red light of the sensor's light source conspicuous.

[0105] In one embodiment, when the total light transmittance of a 2 mm thick composition of the present invention is measured, the total light transmittance in the wavelength range of 400 nm to less than 750 nm is 1.0% or less. The total light transmittance is preferably 0.8% or less, and more preferably 0.5% or less. The lower limit is not particularly limited, and is usually 0.0% or more. Since the total light transmittance is below the above upper limit, the composition of the present invention can be used as a sensor cover with a design that does not allow the contents of the sensor to be seen.

[0106] <Method for producing the composition> There are no limitations on the method of producing the composition of the present invention, and a wide range of known methods for producing polycarbonate compositions can be used. For example, a method may be used in which the polycarbonate resin (A), the infrared absorber (B), and other components to be added as needed are pre-mixed using various mixers such as a tumbler or Henschel mixer, and then melt-kneaded using a mixer such as a Banbury mixer, roll, braver, single-screw extruder, twin-screw extruder, or kneader. When a dye (C) is added, it is generally added in the form of a masterbatch that has been pre-mixed with the polycarbonate resin (A). The melt-kneading temperature is not particularly limited, but is usually in the range of 240 to 320°C.

[0107] The composition of the present invention can be used to produce various molded products by molding pellets obtained by pelletizing the above-described composition using various molding methods. Alternatively, molded products can be produced by directly molding a resin that has been melt-kneaded in an extruder, without going through the pellet stage.

[0108] <Molded products> The molded articles obtained from the composition of the present invention effectively block visible light and have high transmittance at 940 nm, making them suitable for use as infrared sensor components in the automotive, office automation equipment, home appliance, and electrical / electronic fields. For example, they can be used in products such as: monitoring stores, houses, facilities, train stations, and airports; access control and personal authentication; disaster prevention purposes such as monitoring road disasters (landslides, etc.), dam water levels, and active volcanoes; traffic flow monitoring, automatic speed enforcement devices, and automatic license plate recognition devices; in the automotive field, driver face orientation recognition, drowsiness prevention devices, night vision, rear sonar, lane departure prevention, following distance maintenance, and automatic accident avoidance; remote control devices for electrical equipment such as televisions, audio equipment, and air conditioning equipment; counting devices for items such as fruit; and optical character recognition devices using near-infrared light. In particular, the molded article of the present invention can be suitably used as a component for an infrared sensor that utilizes infrared light in the 900-950 nm range. [Examples]

[0109] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to the following examples unless its essence is changed.

[0110] 1.Raw materials The ingredients listed in Table 1 were used as raw materials.

[0111] [Table 1]

[0112] 2. △A of infrared absorber (B) 850 / △A 800 Calculation Test specimen 1:A-1:B-1 = 100:0.005 (W / W) Test specimen 2: A-1: ​​B-2 = 100: 0.005 (W / W) Test specimen 3: A-1 only

[0113] The above components were mixed in a tumbler for 20 minutes according to the above proportions. Then, the mixture was melt-kneaded using a twin-screw extruder (Shibaura Machinery Co., Ltd. "TEM-26SS") at a cylinder temperature of 280°C and a discharge rate of 25 kg / h, and the composition was obtained by strand cutting. The obtained pellets were dried at 120°C for 5 hours in a hot air circulation dryer. Then, using an injection molding machine (Shibaura Machinery Co., Ltd. "EC50SXII") at the same temperature as the extrusion temperature and a mold temperature of 80°C, flat test pieces 1 to 3 with an area of ​​90 × 60 mm and a thickness of 3 mm were obtained.

[0114] The absorption curves of test specimens 1-3 were measured under the following measurement conditions. • Equipment: UV-Vis-Near-Infrared Spectrophotometer (Shimadzu Corporation "UV-3100PC") • Measurement range: 300-2000nm in 1nm increments.

[0115] The difference absorption curve B-1 was obtained by subtracting the absorbance of test specimen 3 at each wavelength from the absorbance of test specimen 1 at each wavelength. The difference absorption curve B-2 was obtained by subtracting the absorbance of test specimen 3 at each wavelength from the absorbance of test specimen 2 at each wavelength. Each △A800 and △A 850 Find △A 850 / △A 800 The result was calculated. 850 / △A 800 This is 0.170, and is the value of triangle A in B-2. 850 / △A 800 The value was 0.050. Figure 1 shows the normalized differential absorption curves of B-1 and B-2. Figure 1 is the differential absorption curve of B-1 and B-2, normalized by setting the absorbance at 800 nm of the differential absorption curve of B-1 and B-2 to 1.0. Figure 2 is an enlarged view of Figure 1 in the region of wavelength 800 to 1000 nm and relative absorbance 0.0 to 1.0.

[0116] 3. Manufacturing of the composition Each component listed in Table 1 was blended in the proportions shown in Tables 2 and 3 below, mixed in a tumbler for 20 minutes, and then melt-kneaded using a twin-screw extruder (Shibaura Machinery Co., Ltd. "TEM-26SS") at 280°C and a discharge rate of 25 kg / h. The mixture was then cut into strands to obtain pellets of the compositions according to Examples 1-2, Comparative Examples 1-3, and Reference Example 1.

[0117] 3.2. Molding Each of the obtained pellets was dried at 120°C for 5 hours in a hot air circulating dryer. Then, using an injection molding machine (Shibaura Machine Co., Ltd. "EC50SXII"), stepped flat test pieces with an area of ​​90 × 60 mm and thicknesses of 1 mm, 2 mm, and 3 mm were obtained at the same temperature as the extrusion temperature and a mold temperature of 80°C.

[0118] [Table 2]

[0119] [Table 3]

[0120] 4. Evaluation 4.1. Measurement of Optical Properties In the 2 mm thick portions of the test specimens obtained from the production of each of the above compositions, the total light transmittance at wavelengths from 300 nm to 2000 nm was measured in 2 nm increments using an ultraviolet-visible-near-infrared spectrophotometer (Shimadzu Corporation "UV-3100PC"). Figure 3 shows the transmission spectra of total light transmittance from 300 to 1000 nm for Examples 1 and 2, Comparative Examples 1 to 3, and Reference Example 1. Figure 4 shows the transmission spectra of total light transmittance from 750 to 1000 nm for Examples 1, Comparative Examples 1 and 2. Figure 5 shows the transmission spectra of total light transmittance from 750 to 1000 nm for Examples 2, Comparative Example 3, and Reference Example 1. Figure 6 shows an enlarged view of the transmission spectra of total light transmittance from 350 to 750 nm for Examples 1 and 2, Comparative Examples 1 to 3, and Reference Example 1. Tables 2 and 3 show the maximum wavelength (x) at which the transmittance is 1% in the 300nm to 1000nm range, the total light transmittance at a wavelength 30nm greater than wavelength x (x+30nm), and the total light transmittance at 850nm, 940nm, 950nm, and 960nm.

[0121] As described above, the present invention provides a composition that has good light transmittance in the wavelength band used in infrared sensors and good noise shielding, as well as a molded article containing the composition and an optical filter for infrared sensors.

Claims

1. The composition comprises a polycarbonate resin (A) and an infrared absorbent (B), and when the total light transmittance of the composition with a thickness of 2 mm is measured, the total light transmittance at 940 nm is 88.0% or more. When the total light transmittance of the composition with a thickness of 2 mm is measured, the maximum wavelength (x) at which the total light transmittance is 1.0% or less in the wavelength range of 750 to 860 nm is 810 nm or greater. A composition having a thickness of 2 mm, wherein when the total light transmittance of the composition is measured, the total light transmittance at a wavelength 30 nm greater than the wavelength (x) is 35.0% or less.

2. The composition according to claim 1, wherein the infrared absorbent (B) has a ratio of (absorbance at 850 nm of the differential absorption curve) / (absorbance at 800 nm of the differential absorption curve) ≥ 0.

060. Here, the difference absorption curve is obtained by the following method. 1) Bisphenol A type polycarbonate resin (i) is kneaded at an extrusion temperature of 280°C to produce pellets of the resin (i), and the absorbance of the molded body, which is processed into a 3 mm thick plate shape by injection molding, is measured in the thickness direction to obtain the absorption curve of the resin (i). 2) The resin (i) and the infrared absorbent (B) are kneaded at an extrusion temperature of 280°C to produce pellets of composition (ii) consisting of 100 parts by mass of the resin (i) and 0.005 parts by mass of the infrared absorbent (B). The pellets are then processed into a 3 mm thick plate shape by injection molding, and the absorbance of the molded body is measured in the thickness direction to obtain the absorption curve of composition (ii). 3) The difference absorption curve is obtained by subtracting the absorption curve of composition (ii) from the absorption curve of resin (i).

3. The composition according to claim 1, wherein the amount of the infrared absorber (B) is 0.02 parts by mass or more and 0.50 parts by mass or less per 100 parts by mass of the polycarbonate resin (A).

4. Furthermore, it contains a dye (C) whose maximum absorption wavelength is less than 700 nm. The composition according to claim 1, wherein the content of the dye (C) is 0.01 parts by mass or more and 1.00 parts by mass or less per 100 parts by mass of the polycarbonate resin (A).

5. The composition according to claim 4, wherein the dye (C) contains two or more dyes with different maximum absorption wavelengths.

6. The composition according to claim 1, wherein the infrared absorber (B) does not contain a quaterylene-based compound.

7. The composition according to claim 1, wherein the infrared absorber (B) comprises an anthraquinone-based compound.

8. The resin composition according to claim 1, wherein when the total light transmittance of the composition with a thickness of 2 mm is measured, the total light transmittance at 700 nm is 1.0% or less.

9. The resin composition according to claim 1, wherein when the total light transmittance of the composition with a thickness of 2 mm is measured, the total light transmittance in the wavelength range of 400 nm to less than 750 nm is 1.0% or less.

10. A molded article comprising the composition according to any one of claims 1 to 9.

11. An optical filter for an infrared sensor, comprising the molded body described in claim 10.

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