Film, multilayer body, and heat-bent molded body

A polycarbonate resin film blended with a yellow dye and ultraviolet absorber addresses the challenge of blue LED glare and UV protection, ensuring effective light transmission and glare suppression.

WO2026075059A1PCT designated stage Publication Date: 2026-04-09MITSUBISHI GAS CHEM CO INC
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Patent Information

Authority / Receiving Office
WO · WO
Patent Type
Applications
Current Assignee / Owner
Filing Date
2025-09-29
Publication Date
2026-04-09

AI Technical Summary

Technical Problem

Existing polycarbonate resin films used in sunglasses struggle to effectively suppress glare from blue LEDs while maintaining sufficient transmission of light at 485 nm and protecting against ultraviolet rays.

Method used

A film comprising polycarbonate resin blended with a yellow dye and an ultraviolet absorber, where the yellow dye has a specific absorption coefficient at 520 nm and a particle size of 1/ppm·μm or less, and the film is designed to have a light transmittance of 20.0% or more at 485 nm and 5.0% or less at 460 nm, along with a thickness of 200 to 600 μm.

Benefits of technology

The film effectively cuts ultraviolet rays, suppresses glare from blue LEDs, and allows sufficient transmission of light at 485 nm, enhancing visibility and protection.

✦ Generated by Eureka AI based on patent content.

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Abstract

Provided are: a film which is capable of blocking ultraviolet rays and suppressing glare of a blue LED, and through which light having a wavelength of 485 nm or more can transmit; a multilayer body; and a heat-bent molded body. A film according to the present disclosure comprises a polycarbonate resin, a yellow dye, and an ultraviolet ray absorbing agent. The yellow dye exhibits an absorbance index (I520) of not more than 1.0×10-7 / ppm·µm with respect to a wavelength of 520 nm. With respect to 100 parts by mass of the polycarbonate resin, the contained amount of the yellow dye is 100-4000 mass ppm and the contained amount of the ultraviolet ray absorbing agent is 0.01-1 parts by mass. The average light transmittance of the film with respect to wavelengths of 350-460 nm is not more than 5.0%. The light transmittance of the film with respect to a wavelength of 485 nm is not less than 20.0%.
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Description

Films, multilayer bodies, and heat-bent molded bodies

[0001] This invention relates to films, multilayers, and heat-bendable molded articles. In particular, it relates to films having polycarbonate resin as a main component.

[0002] Polycarbonate resin is produced by the condensation polymerization of aromatic diols such as bisphenol A and carbonate precursors such as phosgene. It possesses excellent impact strength, numerical stability, heat resistance, and transparency, and is applied to a wide range of fields, including exterior materials for electrical and electronic products, automotive parts, building materials, and optical components.

[0003] On the other hand, optical lenses used in sunglasses and the like require a transmittance that does not affect the field of view while also preventing glare from external light sources. Furthermore, they need to protect the eyes from harmful light rays of specific wavelengths, such as ultraviolet light. Therefore, various technologies have been developed to use polycarbonate resin, which possesses excellent optical properties in addition to mechanical properties, for optical lenses used in outdoor activities such as sunglasses (Patent Documents 1, 2, etc.).

[0004] Japanese Patent Publication No. 2019-202542, International Publication No. 2019 / 066493

[0005] Previously, the incorporation of UV absorbers into polycarbonate resin films used for sunglass lenses has been considered. However, in recent years, the glare from blue LEDs (Light Emitting Diodes) has become a problem, and there is a demand for polycarbonate resin films that can suppress the glare of blue LEDs. On the other hand, even if a polycarbonate resin film can suppress the glare of blue LEDs, its usefulness as sunglasses will be reduced if it cannot transmit light with a wavelength of around 485 nm. The present invention aims to solve these problems and provides a film that can cut ultraviolet rays, suppress the glare of blue LEDs, and transmit light of 485 nm or greater, as well as a multilayer and a heat-bending molded article.

[0006] Based on the above problems, the inventors conducted research and found that the above problems can be solved by blending a predetermined amount of a yellow dye having a predetermined absorption coefficient with an ultraviolet absorber into a polycarbonate resin. Specifically, the above problems were solved by the following means: [1] A film comprising a polycarbonate resin, a yellow dye, and an ultraviolet absorber, wherein the yellow dye has an absorption coefficient (I) at a wavelength of 520 nm. 520 ) is 1.0 × 10 -7 A film having a particle size of 1 / ppm·μm or less, a content of the yellow dye per 100 parts by mass of the polycarbonate resin of 100 to 4000 ppm by mass, a content of the ultraviolet absorber of 0.01 to 1 part by mass, an average light transmittance of the film at a wavelength of 350 to 460 nm of 5.0% or less, and a light transmittance of the film at a wavelength of 485 nm of 20.0% or more. [2] The film according to [1], wherein the thickness of the film is 200 to 600 μm. [3] The yellow dye is the ratio of the absorption coefficient at a wavelength of 520 nm to the absorption coefficient at a wavelength of 460 nm. 520 / I 460 3.0 x 10 -3 The film according to [1] or [2], which is as follows: [4] The film according to any one of [1] to [3], wherein the yellow dye comprises at least one compound represented by formula (YP). Formula (YP) [5] The film according to any one of [1] to [4], wherein the ultraviolet absorber comprises a compound represented by formula (UV-1). (In formula (UV-1), R 1 R is a group consisting of a hydrocarbon group having 1 to 10 carbon atoms, or a combination of a hydrocarbon group having 1 to 10 carbon atoms and -O- and / or -C(=O)-, 2 ~R 4is, independently of each other, a hydroxyl group, a hydrocarbon group having 1 to 10 carbon atoms, or a group composed of a combination of a hydrocarbon group having 1 to 10 carbon atoms, -O- and / or -C(=O)-, n2 is an integer of 0 to 3, and n3 and n4 are each independently an integer of 0 to 4.) [6] The film according to any one of [1] to [5], wherein the light transmittance at a wavelength of 460 nm is 3.0% or less. [7] The thickness of the film is 200 to 600 μm, and the yellow dye is I 520 / I 460 is 3.0×10 -3 or less, the yellow dye contains at least one compound represented by the formula (YP), the ultraviolet absorber contains a compound represented by the formula (UV-1), and the light transmittance at a wavelength of 460 nm is 3.0% or less. The film according to any one of [1] to [6]. Formula (YP) (In the formula (UV-1), R 1 is a hydrocarbon group having 1 to 10 carbon atoms, or a group composed of a combination of a hydrocarbon group having 1 to 10 carbon atoms, -O- and / or -C(=O)-, R 2 to R 4 are each independently a hydroxyl group, a hydrocarbon group having 1 to 10 carbon atoms, or a group composed of a combination of a hydrocarbon group having 1 to 10 carbon atoms, -O- and / or -C(=O)-, n2 is an integer of 0 to 3, and n3 and n4 are each independently an integer of 0 to 4.) [8] A multilayer body having the film according to any one of [1] to [7] and a polarizing film. [9] A thermally bent molded body of the multilayer body according to [8].

[0007] According to the present invention, it has become possible to provide a film that can cut ultraviolet rays, suppress the glare of blue LEDs, and further transmit light of 485 nm or more, as well as a multilayer body and a thermally bent molded body.

[0008] It is a schematic diagram for explaining an example of the layer structure of the multilayer body, the thermally bent molded body, or sunglasses of the present embodiment.

[0009] The following describes in detail embodiments for carrying out the present invention (hereinafter simply referred to as "these embodiments"). These embodiments are illustrative examples for explaining the present invention, and the present invention is not limited to these embodiments. In this specification, "~" is used to mean that the numerical values ​​before and after it are included as the lower and upper limits. "A~B" means A or greater and B or less. Furthermore, the upper and lower limits of the numerical values ​​in this specification are given as examples of these embodiments, regardless of the combination of the upper and lower limits.

[0010] In this specification, preferred combinations of embodiments are considered more preferred embodiments. In this specification, all physical properties and characteristic values ​​are given at 23°C unless otherwise specified. In this specification, "film" refers to a molded article that is thin in thickness relative to its length and width, and is generally flat. In this specification, "film" includes sheets and may be single-layer or multi-layer. If the measurement methods etc. described in the standards shown in this specification differ from year to year, unless otherwise specified, the standards as of January 1, 2024 shall apply. If the measurement methods etc. described in the standards shown in this specification have been abolished as of January 1, 2024, the standards at the time of abolition shall apply. Figure 1 may not be consistent with reality in terms of scale, etc.

[0011] The film of this embodiment is a film comprising a polycarbonate resin, a yellow dye, and an ultraviolet absorber, wherein the yellow dye has an absorption coefficient (I) at a wavelength of 520 nm. 520 ) is 1.0 × 10 -7The film is characterized by having a particle size of 1 / ppm·μm or less, a content of the yellow dye of 100 to 4000 ppm per 100 parts by mass of the polycarbonate resin, a content of 0.01 to 1 part by mass of the ultraviolet absorber, an average light transmittance of the film at wavelengths of 350 to 460 nm of 5.0% or less, and a light transmittance of the film at a wavelength of 485 nm of 20.0% or more. With this configuration, it is possible to provide a film that can cut ultraviolet rays, suppress the glare of blue LEDs, and transmit light of 485 nm or higher. The UV cut is achieved by blending an ultraviolet absorber into the polycarbonate resin. Furthermore, it was hypothesized that the glare of blue LEDs originates from light with a peak wavelength of 460 nm, and that if light around 460 nm can be cut, the glare of blue LEDs can be cut. On the other hand, if light rays with a wavelength of 485 nm are also cut out in addition to light rays with a wavelength of 460 nm, the visibility of objects will decrease, resulting in a lack of performance as sunglasses. Under these circumstances, the inventors conducted studies and found that the absorption coefficient at a wavelength of 520 nm (I 520 ) is 1.0 × 10 -7 We found that by using a predetermined amount of yellow dye with a particle size of 1 / ppm·μm or less, it is possible to cut down on the glare of blue LEDs while still allowing sufficient transmission of 485nm light.

[0012] The embodiments of the present invention will be described in detail below, but the description of the constituent elements described below is merely one example of an embodiment of the present invention and is not limited to these.

[0013] <Polycarbonate Resin> The film of this embodiment includes a polycarbonate resin. By using a polycarbonate resin, a film with excellent transparency can be obtained. The polycarbonate resin used in this embodiment is not particularly limited as long as it contains a carbonate ester bond--[O-R-OC(=O)]- unit in the molecular main chain (where R is a hydrocarbon group, specifically an aliphatic group, an aromatic group, or a group containing both an aliphatic and an aromatic group, and furthermore, a linear or branched structure). In this embodiment, an aromatic polycarbonate resin is preferred, and a polycarbonate resin having a bisphenol skeleton is more preferred. In the polycarbonate resin having a bisphenol skeleton, it is preferable that 90 mol% or more (preferably 95 mol% or more, more preferably 97 mol% or more) of the total constituent units are constituent units having a bisphenol skeleton. The bisphenol is preferably at least one selected from bisphenol A, bisphenol AP, bisphenol Z, and bisphenol TMC, and is more preferably bisphenol A.

[0014] Furthermore, the viscosity-average molecular weight (Mv) of the polycarbonate resin is preferably 10,000 or more, more preferably 12,000 or more, even more preferably 15,000 or more, and even more preferably 18,000 or more. Setting it above the lower limit tends to further improve the durability of the substrate. The upper limit of the viscosity-average molecular weight (Mv) of the polycarbonate resin is preferably 50,000 or less, more preferably 40,000 or less, and even more preferably 30,000 or less. Setting it below the upper limit tends to further improve the moldability of the substrate. The viscosity-average molecular weight (Mv) is determined by using methylene chloride as the solvent, and calculating the intrinsic viscosity [η] (unit dL / g) at a temperature of 25°C using an Ubbelohde viscometer, and using Schnell's viscosity formula, i.e., η = 1.23 × 10⁻⁶. -4 ×Mv 0.83 This refers to the value calculated from [the specified values]. When using two or more types of polycarbonate resin, the viscosity-average molecular weight of the mixture is used.

[0015] In this embodiment, the polycarbonate resin may be bio-polycarbonate resin or recycled polycarbonate resin.

[0016] The method for producing polycarbonate resin 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.

[0017] Further details regarding the polycarbonate resin can be found in paragraphs 0011 to 0020 of Japanese Patent Application Publication No. 2012-144604 and paragraphs 0014 to 0035 of Japanese Patent Application Publication No. 2019-002023, without departing from the spirit of this embodiment, and these contents are incorporated herein.

[0018] The polycarbonate resin content in the film of this embodiment is preferably 85% by mass or more, more preferably 90% by mass or more, even more preferably 95% by mass or more, even more preferably 97% by mass or more, even more preferably 98% by mass or more, and may also be 99% by mass or more. Furthermore, the polycarbonate resin content in the film of this embodiment is preferably such that, in 100% by mass of the film, all components other than the yellow dye and ultraviolet absorber are polycarbonate resin. If the film of this embodiment contains two or more types of polycarbonate resin, it is preferable that the total amount falls within the above range.

[0019] <Yellow Dye> The film of this embodiment has an absorption coefficient (I) at a wavelength of 520 nm. 520 ) (Hereafter, simply, "I 520 (Sometimes referred to as "") 1.0 x 10 -7 The film contains a yellow dye with a particle size of 1 / ppm·μm or less in a ratio of 100 to 4000 ppm by mass per 100 parts by mass of polycarbonate resin. By including the specified yellow dye in the above ratio, a film can be obtained that effectively cuts glare from blue LEDs while transmitting light rays with a wavelength of approximately 485 nm. The term "yellow dye" refers to a dye that appears yellow to the human eye.

[0020] The yellow dye I 520 90.0 x 10 -9 It is preferable that the particle size is less than or equal to ppm·μm, and is 50.0 × 10 -9 It is more preferable that the particle size be less than or equal to ppm·μm, and 10.0 × 10 -9 It is even more preferable that the particle size be less than or equal to ppm·μm, and the size is 7.0 × 10 -9 It is even more preferable that the particle size be less than or equal to ppm·μm. 520 By setting it below the aforementioned upper limit, the visibility of the object tends to improve further. 520 The lower limit is preferably 0, but 1.0 × 10 -10 Even if the particle size is / ppm·μm or larger, it will still adequately meet the required performance. The film of this embodiment may contain only one of the above-mentioned yellow dyes, or it may contain two or more. If it contains two or more, I 520 This is the I of each yellow dye. 520 This is the sum (weighted average) of the values ​​obtained by multiplying by the mass fraction of each yellow dye. The absorption coefficient I at a wavelength of 460 nm will be described later. 460 The same applies to this matter.

[0021] The yellow dye used in this embodiment has an absorption coefficient (I) at a wavelength of 520 nm. 520 ) and the absorption coefficient at a wavelength of 460 nm (I 460 The ratio of I 520 / I 460 However, for example, 50.0 x 10 -3 The following is true: 35.0 × 10 -3 Preferably, it is 30.0 × 10 -3 It is more preferable that the following conditions apply: 10.0 × 10 -3 It is even more preferable that the following conditions apply: 7.0 × 10 -3 It is even more preferable that the following conditions be met: 3.0 × 10 -3 It is even more preferable that the following conditions apply, and furthermore, 2.5 × 10 -3 Below, 2.0 x 10 -3 Below, 1.5 x 10 -3 The following is preferable: The above yellow dye (especially I 520 / I 460 3.0 x 10 -3By using the following yellow dyes, the yellow tint of the resulting film can be suppressed. In other words, even with a reduced amount of yellow dye, the glare originating from the blue LED can be effectively suppressed. 520 / I 460 The lower limit is, for example, 1.0 × 10 -3 That's all.

[0022] The method for measuring the absorption coefficient of the yellow dye can be the general method used to measure the absorption coefficient of dyes. Specifically, it can be measured using the method described in the examples.

[0023] Examples of yellow dyes include dyes whose color index (CI) is classified as solvent yellow. The yellow dyes used in this embodiment include solvent yellow 33, 201, 93, 104, 167, etc., and preferably include at least one of solvent yellow 33, 201 (compounds represented by formula (YP)). Formula (YP) Furthermore, the molecular weight of the yellow dye used in this embodiment is preferably 200 to 800.

[0024] The yellow dye content in the film of this embodiment is 100 ppm by mass or more, preferably 200 ppm by mass or more, more preferably 300 ppm by mass or more, even more preferably 500 ppm by mass or more, even more preferably 700 ppm by mass or more, and even more preferably 900 ppm by mass or more, per 100 parts by mass of polycarbonate resin. By setting the yellow dye content above the lower limit, the effect of cutting ultraviolet rays and high-energy visible light tends to be further improved. Furthermore, the yellow dye content in the film of this embodiment is 4000 ppm by mass or less, preferably 3500 ppm by mass or less, more preferably 2500 ppm by mass or less, even more preferably 1500 ppm by mass or less, even more preferably 1300 ppm by mass or less, and even more preferably 1100 ppm by mass or less, per 100 parts by mass of polycarbonate resin. By keeping the yellow dye content below the aforementioned upper limit, the yellowing of the film can be suppressed more effectively. Furthermore, in this embodiment, as described above, 520 / I 460 3.0 x 10 -3 By using the following yellow dyes, glare from blue LEDs can be effectively suppressed even with a reduced amount of yellow dye. The film of this embodiment may contain only one type of yellow dye, or it may contain two or more types. When two or more types are included, it is preferable that the total amount is within the above range.

[0025] The film of this embodiment is I 520 1.0 × 10 -7 The present invention may contain yellow dyes in a quantity greater than ppm·μm, but it is preferable that they are substantially absent, without departing from the spirit of the present invention. 520 1.0 × 10 -7 Substantially free of yellow dyes exceeding ppm·μm means that in the film of this embodiment, I 520 1.0 × 10 -7 The amount of yellow dye greater than / ppm·μm is I 520 1.0 × 10 -7 / This means that the content of yellow dye that is less than ppm·μm is less than 1.5% by mass, preferably less than 1% by mass, more preferably less than 0.7% by mass, even more preferably less than 0.5% by mass, even more preferably less than 0.3% by mass, and even more preferably less than 0.1% by mass.

[0026] <UV Absorber> The film of this embodiment contains a UV absorber. By including a UV absorber, a film with excellent weather resistance can be obtained that effectively suppresses UV transmission. The UV absorber is preferably one having a maximum absorption wavelength of 280 nm to 380 nm, and more preferably one having a maximum absorption wavelength of only 280 nm to 380 nm. However, if the UV absorber is also a yellow dye, it shall be a yellow dye. Examples of UV absorbers include benzotriazole-based UV absorbers, benzophenone-based UV absorbers, benzoate-based UV absorbers, hindered amine-based UV absorbers, and triazine-based UV absorbers, and it is preferable to include a triazine-based UV absorber.

[0027] Benzotriazole-based UV absorbers include 2-(2-hydroxy-5-t-octylphenyl)-2H-benzotriazole, 2-(3-t-butyl-2-hydroxy-5-methylphenyl)-5-chloro-2H-benzotriazole, 2-[5-chloro(2H)-benzotriazole-2-yl]-4-methyl-6-(t-butyl)phenol, 2,4-di-tert-butyl-6-(5-chlorobenzotriazole-2-yl)phenol, (2-[5-chloro(2H)-benzotriazole-2-yl]-4,6-di(tert-pentyl)phenol), and 3-[3-tert-butyl-5-(5 Preferred examples include [(2H)-benzotriazole-2-yl)-4-hydroxyphenyl]octylpropionate, 2-(3-t-butyl-5-methyl-2-hydroxyphenyl)-5-chlorobenzotriazole, 2-(2H-benzotriazole-2-yl)-6-dodecyl-4-methylphenol, 2-(2H-benzotriazole-2-yl)-p-cresol, 2-[(2H)-benzotriazole-2-yl]-4,6-bis-(1-methyl-1-phenylethyl)phenol, 2,2'-methylenebis[6-(benzotriazole-2-yl)-4-t-octylphenol], etc.

[0028] The triazine-based ultraviolet absorber used in this embodiment preferably contains a compound represented by formula (UV-1), more preferably contains a compound represented by formula (UV-2), and even more preferably contains a compound represented by formula (UV-3). (In formula (UV-1), R 1 R is a group consisting of a hydrocarbon group having 1 to 10 carbon atoms, or a combination of a hydrocarbon group having 1 to 10 carbon atoms and -O- and / or -C(=O)-, 2 ~R 4 Each of these groups is independently a hydroxyl group, a hydrocarbon group having 1 to 10 carbon atoms, or a group consisting of a hydrocarbon group having 1 to 10 carbon atoms and -O- and / or -C(=O)-, where n2 is an integer from 0 to 3, and n3 and n4 are independently integers from 0 to 4.

[0029] R 1The group is a hydrocarbon group having 1 to 10 carbon atoms, or a combination of a hydrocarbon group having 1 to 10 carbon atoms and -O- and / or -C(=O)-, preferably an aliphatic hydrocarbon group having 1 to 10 carbon atoms, or a combination of an aliphatic hydrocarbon group having 1 to 10 carbon atoms and -O- and / or -C(=O)-, more preferably an aliphatic hydrocarbon group having 1 to 10 carbon atoms, even more preferably a linear aliphatic hydrocarbon group having 3 to 10 carbon atoms, and even more preferably a linear alkyl group having 3 to 10 carbon atoms. 1 The number of carbon atoms in the hydrocarbon group (preferably an aliphatic hydrocarbon group, more preferably an alkyl group) is preferably 2 or more, more preferably 3 or more, even more preferably 4 or more, even more preferably 5 or more, and also preferably 9 or less, more preferably 8 or less, and even more preferably 7 or less.

[0030] R 2 ~R 4 Each of these is independently a hydroxyl group, a hydrocarbon group having 1 to 10 carbon atoms, or a group consisting of a hydrocarbon group having 1 to 10 carbon atoms and -O- and / or -C(=O)-, R 2 ~R 4 At least one of them is a hydroxyl group, R 2 ~R 4 At least one of the other members is preferably a hydrocarbon group having 1 to 10 carbon atoms, or a group consisting of a hydrocarbon group having 1 to 10 carbon atoms and -O- and / or -C(=O)-. 2 ~R 4 The hydrocarbon group having 1 to 10 carbon atoms may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group, and is preferably a linear aliphatic hydrocarbon group (preferably a linear alkyl group) or a phenyl group. 2 ~R 4 The number of carbon atoms in the hydrocarbon group having 1 to 10 carbon atoms is preferably 2 or more, more preferably 3 or more, even more preferably 4 or more, even more preferably 5 or more, and also preferably 9 or less, more preferably 8 or less, and even more preferably 7 or less.

[0031] n2 is an integer from 0 to 3, preferably an integer from 0 to 2, more preferably 0 or 1, and even more preferably 1. n3 and n4 are each independently an integer from 0 to 4, preferably an integer of 1 or more, more preferably an integer of 2 or more, even more preferably an integer of 3 or more, and preferably an integer of 4 or less.

[0032] (In formula (UV-2), R 11 , R 31 , and R 41 are each independently an aliphatic hydrocarbon group having 3 to 10 carbon atoms. R 2 , R 32 , and R 42 are each independently a hydroxyl group, a hydrocarbon group having 1 to 10 carbon atoms, or a group composed of a combination of a hydrocarbon group having 1 to 10 carbon atoms, -O- and / or -C(=O)-. n2, n3-1, and n4-1 are each independently an integer from 0 to 3.)

[0033] R 11 , R 31 , and R 41 are each independently an aliphatic hydrocarbon group having 3 to 10 carbon atoms. The number of carbon atoms of the aliphatic hydrocarbon group is preferably 4 or more, more preferably 5 or more, preferably 9 or less, more preferably 8 or less, and even more preferably 7 or less. The aliphatic hydrocarbon group is preferably a linear aliphatic hydrocarbon group, and more preferably a linear alkyl group. The aliphatic hydrocarbon group is preferably a linear aliphatic hydrocarbon group, and more preferably a linear alkyl group. A propyl group, a butyl group, a pentyl group, and a hexyl group are preferred, and a butyl group, a pentyl group, and a hexyl group are more preferred.

[0034] R 2 , R 32 , and R 42is, independently of each other, a hydroxyl group, a hydrocarbon group having 1 to 10 carbon atoms, or a group consisting of a combination of a hydrocarbon group having 1 to 10 carbon atoms, -O- and / or -C(=O)-. R 2 The preferable range of is the same as that of R in the formula (UV-1). R 2 is the same as that in the formula (UV-1). R 32 , and R 42 The preferable range of is, independently of each other, preferably a hydroxyl group and an alkyl group having 1 to 3 carbon atoms, more preferably a hydroxyl group and a methyl group. n2 is an integer of 0 to 3, preferably 1 or 2, and more preferably 1. n3-1 and n4-1 are, independently of each other, integers of 0 to 3, preferably 1 or 2, and more preferably 2.

[0035] (In the formula (UV-3), R 11 , R 31 , and R 41 are, independently of each other, aliphatic hydrocarbon groups having 3 to 10 carbon atoms.)

[0036] R 11 , R 31 , and R 41 are, independently of each other, aliphatic hydrocarbon groups having 3 to 10 carbon atoms. The number of carbon atoms of the aliphatic hydrocarbon group is preferably 4 or more, more preferably 5 or more, preferably 9 or less, more preferably 8 or less, and even more preferably 7 or less. The aliphatic hydrocarbon group is preferably a linear aliphatic hydrocarbon group, more preferably a linear alkyl group. The aliphatic hydrocarbon group is preferably a linear aliphatic hydrocarbon group, more preferably a linear alkyl group, even more preferably a propyl group, a butyl group, a pentyl group, or a hexyl group, and still more preferably a butyl group, a pentyl group, or a hexyl group.

[0037] Hereinafter, triazine-based ultraviolet absorbers used in this embodiment will be exemplified. Needless to say, the ultraviolet absorbers used in this embodiment are not limited to these.

[0038] The molecular weight of the ultraviolet absorber used in this embodiment is preferably 400 or more, more preferably 500 or more, even more preferably 550 or more, even more preferably 610 or more, and even more preferably 650 or more. By setting the molecular weight of the ultraviolet absorber to be above the lower limit, the ultraviolet absorber becomes less volatile, and roll soiling can be suppressed more effectively. Furthermore, the molecular weight of the ultraviolet absorber used in this embodiment is preferably 1000 or less, more preferably 900 or less, and even more preferably 800 or less. By setting the molecular weight of the ultraviolet absorber to be below the upper limit, the compatibility with the polycarbonate resin tends to improve further.

[0039] The amount of ultraviolet absorber in the film of this embodiment is 0.01 parts by mass or more, preferably 0.05 parts by mass or more, more preferably 0.08 parts by mass or more, and also 1 part by mass or less, preferably 0.8 parts by mass or less, more preferably 0.5 parts by mass or less, even more preferably 0.3 parts by mass or less, and even more preferably 0.2 parts by mass or less, per 100 parts by mass of polycarbonate resin. By setting the amount of ultraviolet absorber above the lower limit, the weather resistance of the resulting molded product tends to improve further. Furthermore, by setting the amount of ultraviolet absorber below the upper limit, the weather resistance of the resulting molded product tends to improve further without reducing hue, mechanical properties, or heat resistance. The film of this embodiment may contain only one type of ultraviolet absorber or two or more types. When two or more types are included, it is preferable that the total amount is within the above range.

[0040] <Other Components> The film of this embodiment may or may not contain other components other than those listed above. Examples of other components include antioxidants, release agents, heat stabilizers, flame retardants, flame retardant aids, colorants other than yellow dyes, antistatic agents, fluorescent whitening agents, antifogging agents, flow improvers, plasticizers, dispersants, antibacterial agents, antiblocking agents, impact improvers, sliding improvers, hue improvers, acid trapping agents, etc. Furthermore, the film of this embodiment may be formulated with additives described in paragraphs 0047 to 0103 of International Publication No. 2021 / 241471, without departing from the spirit of the present invention, and this content is incorporated herein. If other components are included, their total content is preferably 0.001 to 3% by mass of the film, more preferably 2% by mass or less, even more preferably 1% by mass or less, even more preferably 0.5% by mass or less, even more preferably 0.1% by mass or less, and may be less than 0.01% by mass. The other components may consist of only one type or two or more types. If two or more other components are included, it is preferable that the total amount is within the above range. An example of the film in this embodiment is one that does not contain a black coloring agent. Another example of the film in this embodiment is one that does not contain any coloring agents other than a yellow dye.

[0041] <Film Thickness> The film of this embodiment is preferably 200 to 600 μm thick. By setting the film thickness to be above the lower limit, the average light transmittance of the film at wavelengths of 350 to 460 nm tends to be reduced. By setting the film thickness to be below the upper limit, the heat bending processability tends to be improved. When the film of this embodiment is laminated with lenses such as eyeglasses, its thickness is preferably half or less the thickness of the lens. The film thickness is more preferably 250 μm or more, even more preferably 300 μm or more, even more preferably 350 μm or more, and most preferably 550 μm or less.

[0042] <Light transmittance of the film and b *Value > The film of this embodiment has an average light transmittance of 5.0% or less at wavelengths of 350 to 460 nm, and a light transmittance of 20.0% or more at wavelengths of 485 nm. The light transmittance is mainly achieved by incorporating a yellow dye. The average light transmittance of the film of this embodiment at wavelengths of 350 to 460 nm is 5.0% or less, preferably 3.0% or less, more preferably 2.0% or less, and the lower limit is substantially greater than 0%.

[0043] The light transmittance of the film of this embodiment at a wavelength of 485 nm is 20.0% or more, preferably 30.0% or more, more preferably 40.0% or more, even more preferably 50.0% or more, even more preferably 60.0% or more, and even more preferably 70.0% or more. The upper limit is 100%, but even if it is 99.0% or less, or even 95.0% or less, the required performance can be met.

[0044] Furthermore, the light transmittance of the film of this embodiment at a wavelength of 460 nm is preferably 5.0% or less, more preferably 4.0% or less, even more preferably 3.0% or less, even more preferably 2.0% or less, and especially even more preferably 1.8% or less. There is no lower limit to the light transmittance of the film of this embodiment at a wavelength of 460 nm, but it is practical to be greater than 0%. A film that satisfies the above-mentioned light transmittance can be achieved, for example, by blending a predetermined amount of a predetermined yellow dye into a polycarbonate resin.

[0045] The film of this embodiment is b * A low value is preferable. Specifically, the b of the film. * The value is preferably 112 or less, more preferably 110 or less, even more preferably 105 or less, even more preferably 101 or less, even more preferably 90 or less, and even more preferably 85 or less. The b of the film of this embodiment * The lower limit of the value may be 0, but 1 or greater is practical, and 3 or greater also sufficiently satisfies the required performance.* The values ​​represent the amount of yellow dye used and the type of yellow dye (especially I 520 / I 460 This is achieved by adjusting the value.

[0046] Light transmittance of the film, b * A general method can be used to measure the value. Specifically, it can be measured using the method described in the examples.

[0047] <Film Manufacturing Method> A known manufacturing method can be used to manufacture the film of this embodiment. For example, a polycarbonate resin, a yellow dye, and an ultraviolet absorber, along with other components as needed, may be melt-kneaded and then extruded into a film. Furthermore, it is preferable that the film be manufactured by roll-to-roll molding. It is preferable that the film of this embodiment is not an injection-molded product formed by injection molding. Therefore, the film of this embodiment usually does not have weld lines.

[0048] <Winding Body> The film of this embodiment can be in the form of a winding body wound around a core material.

[0049] <Multilayer> The multilayer of this embodiment comprises the film of this embodiment and a polarizing film. An example of the multilayer of this embodiment is a polarizing sheet. In this embodiment, the first embodiment of the multilayer is a sheet laminated in the order of the film of this embodiment, a polarizing film, and a polarizing film substrate. That is, the film of this embodiment is preferably used as at least one of the polarizing film substrates of the polarizing sheet. The polarizing film substrate is usually bonded to the polarizing film via an adhesive. In this embodiment, one of the polarizing film substrates of the polarizing sheet is the film of this embodiment. The other polarizing film substrate of the polarizing sheet can be a polarizing film substrate of a known polarizing sheet, or it may be the film of this embodiment. The polarizing film can be a known one, and an example is a polyvinyl alcohol (PVA) film in which iodine or a dichroic organic dye is adsorbed or impregnated. The adhesive used to bond the film and / or polarizing film substrate of this embodiment to the polarizing film can be a known adhesive, and examples include acrylic adhesives, urethane adhesives, epoxy adhesives, silicone adhesives, polyvinyl alcohol adhesives, etc. Among these, urethane adhesives are preferred. The thickness of the adhesive is usually 1 μm or more, and usually 30 μm or less. In addition, the polarizing sheet of this embodiment may have a masking film or the like provided on the outside of the film and / or polarizing film substrate of this embodiment.

[0050] In this embodiment, the second embodiment of the multilayer is a sheet laminated in the order of the film of this embodiment, polarizing film substrate, polarizing film, and polarizing film substrate. That is, in addition to the polarizing film substrate, the film of this embodiment can be laminated and used. The polarizing film substrate, polarizing film, adhesive, etc. in the second embodiment are the same as in the first embodiment of the multilayer, and the preferred ranges are also the same.

[0051] Furthermore, in this embodiment, the multilayer body of this embodiment is preferably used in a heat-bent molded body. When the multilayer body of this embodiment is used as a polarizing sheet, the film of this embodiment may be provided on either side of the polarizing film, or on both sides. Also, the film of this embodiment may be a polarizing film substrate, or it may be a film provided separately from the polarizing film substrate. The first embodiment is one in which the film of this embodiment is positioned on the concave side of the polarizing film after heat bending, for example, on the side of the polarizing film substrate 3 in Figure 1. The second embodiment is one in which the film of this embodiment is positioned on the convex side of the polarizing film after heat bending, for example, on the side of the polarizing film substrate 4 in Figure 1. The third embodiment is one in which the film of this embodiment is positioned on both sides of the polarizing film, for example, both the polarizing film substrates 3 and 4 in Figure 1 are the film of this embodiment. In Figure 1, the polarizing sheet is lens 1, the polarizing film 2, and the polarizing film substrates 3 and 4 are bent, but it goes without saying that this embodiment also includes cases where the polarizing film is not bent.

[0052] In this embodiment, the polarizing sheet is preferably used as a polarizing sheet for liquid crystal display devices, a polarizing lens (sunglass lens, ski goggle lens, prescription eyeglass lens, camera viewfinder lens), a cover for various instruments, automobile glass, train glass, polarizing sheets for in-vehicle display panels and electronic device housings, an in-vehicle rearview mirror, a silver mirror for helmets, etc.

[0053] The multilayer body of this embodiment may have a hard coat layer. The hard coat layer is preferably obtained by applying a hard coat material that can be cured by heat or by active energy rays and then curing it. An example of a material (paint) that can be cured using active energy rays is a resin composition consisting of one or more monofunctional or polyfunctional (preferably 2 to 10-functional) (meth)acrylate monomers or oligomers, and preferably a resin composition containing a monofunctional or polyfunctional (preferably 2 to 10-functional) urethane (meth)acrylate oligomer. These resin compositions preferably contain a photopolymerization initiator as a curing catalyst. Examples of thermosetting materials (paints) include polyorganosiloxane-based and crosslinked acrylic-based materials. Some of these resin compositions are commercially available as hard coat agents for acrylic resin or polycarbonate resin films or sheets, and can be appropriately selected considering their suitability with the painting line. For the hard coat layer, reference can be given to the descriptions in paragraphs 0045 to 0055 of Japanese Patent Publication No. 2013-020130, paragraphs 0073 to 0076 of Japanese Patent Publication No. 2018-103518, and paragraphs 0062 to 0082 of Japanese Patent Publication No. 2017-213771, the contents of which are incorporated herein by reference.

[0054] In addition to the above components, the hard coat layer may also contain light stabilizers, heat stabilizers, flame retardants, flame retardant additives, antistatic agents, fluorescent whitening agents, anti-fogging agents, flow modifiers, plasticizers, dispersants, antibacterial agents, antiblocking agents, impact modifiers, sliding modifiers, color modifiers, acid trapping agents, etc. One of these components may be used, or two or more may be used in combination.

[0055] The multilayer body of this embodiment may further have an infrared-cutting layer.

[0056] The multilayer body of this embodiment is preferably used as a polarizing sheet for liquid crystal display devices, a polarizing lens (sunglass lens, ski goggle lens, prescription eyeglass lens, camera viewfinder lens), a cover for various instruments, automobile glass, train glass, polarizing sheets for in-vehicle display panels and electronic device housings, an in-vehicle rearview mirror, a silver mirror for helmets, etc.

[0057] The present invention will be described in more detail below with reference to examples. The materials, amounts used, proportions, processing content, processing procedures, etc., shown in the following examples can be modified as appropriate, as long as they do not depart from the spirit of the present invention. Therefore, the scope of the present invention is not limited to the specific examples shown below. If the measuring instruments, etc., used in the examples are difficult to obtain due to discontinuation or other reasons, measurements can be taken using other instruments with equivalent performance.

[0058] 1. Raw Materials The following raw materials were used: <Polycarbonate resin (A)> A1: Bisphenol A type polycarbonate sheet resin: Manufactured by Mitsubishi Gas Chemical Company, Inc., S-3000

[0059] <Yellow dye (B)> B1: Plast yellow 8005 (CI: solvent yellow 33), manufactured by Arimoto Chemical Industry Co., Ltd. B2: Plast yellow 8070 (CI: solvent yellow 201), manufactured by Arimoto Chemical Industry Co., Ltd. B3: Plast yellow 8000 (CI: solvent yellow 93), manufactured by Arimoto Chemical Industry Co., Ltd. B4: KP Plast yellow F (CI: solvent yellow 104), manufactured by Kiwa Chemical Industry Co., Ltd. B5: KP Plast yellow MK (CI: solvent yellow 167), manufactured by Kiwa Chemical Industry Co., Ltd. B6: KP Plast yellow HK (CI: solvent yellow 163), manufactured by Kiwa Chemical Industry Co., Ltd.

[0060] <UV absorbers (C)> C1: LA-F70, triazine-based UV absorber, manufactured by ADEKA Corporation C2: LA-31, benzotriazole-based UV absorber, manufactured by ADEKA Corporation

[0061] <Measurement of the Absorption Coefficient of Yellow Dye> Absorption coefficient of yellow dye at wavelengths of 520 nm and 460 nm (I 520 , I 460The absorbance of each yellow dye in a 500 μm thick polycarbonate resin film was measured at wavelengths of 520 nm and 460 nm using a spectrophotometer with a scan speed of 300 nm / min and a sampling interval of 1 nm. The absorbance of a film of the same thickness as the above film but without the yellow dye was measured at wavelengths of 520 nm and 460 nm under the same conditions. The difference in absorbance between the film containing the yellow dye and the film without the yellow dye at each wavelength was taken as the absorbance of each yellow dye in a 500 μm thick film. The absorption coefficient (unit: / ppm·μm) at each wavelength was calculated by dividing this by the dye concentration (50 ppm) and the film thickness (500 μm). A spectrophotometer U-4100 (manufactured by Hitachi High-Tech Corporation) was used for the measurements. Absorption coefficient of the yellow dye at wavelength 520 nm (I 520 Regarding ), in Table 1 or Table 2, the unit is 10 -9 The values ​​are shown in ppm / μm. The ratio of the absorption coefficient of the yellow dye at a wavelength of 520 nm to the absorption coefficient at a wavelength of 460 nm (I 520 / I 460 The figures are shown in Table 1 or Table 2.

[0062] 2. Examples 1-5, Comparative Examples 1-5 <Film Manufacturing> Polycarbonate resin films were manufactured using the following method. Each component listed in Table 1 or 2 was weighed to the amount listed in Table 1 or 2 (Tables 1 and 2 show amounts in parts by mass). After mixing in a tumbler for 15 minutes, the mixture was extruded into a molten state using a T-die melt extruder consisting of a vented twin-screw segment extruder with a barrel diameter of 25 mm and a screw L / D = 30 (Toyo Seiki Co., Ltd., "2D30W2") at a discharge rate of 8 kg / h and a screw rotation speed of 100 rpm. The film was then cooled and solidified using only the first roll of a film / sheet take-up device (Toyo Seiki Co., Ltd., "FT3W20") to produce a polycarbonate resin film. The cylinder / die head temperature was 280°C and the roll temperature was 130°C. The roll speed of the first roll was adjusted so that the final film thickness was 500 μm.

[0063] <Average Light Transmittance at Wavelengths of 350–460 nm> The average light transmittance of the obtained polycarbonate resin film was measured at wavelengths of 350–460 nm. Specifically, a spectrophotometer was used to measure the light transmittance (unit: %) of the film at wavelengths of 350–460 nm under conditions of a scan speed of 300 nm / min and a sampling interval of 1 nm. The average value was calculated from the light transmittance values ​​for each 1 nm wavelength. A spectrophotometer U-4100 (manufactured by Hitachi High-Tech Corporation) was used for the measurement. The following categories were used for evaluation: A: 5.0% or less B: Greater than 5.0%

[0064] <Light transmittance at a wavelength of 460 nm> The light transmittance at a wavelength of 460 nm was measured for the obtained polycarbonate resin film. The light transmittance was measured in the same manner as the average light transmittance for wavelengths of 350 to 460 nm described above. The unit is expressed in %.

[0065] <Light transmittance at a wavelength of 485 nm> The light transmittance at a wavelength of 485 nm was measured for the obtained polycarbonate resin film. The light transmittance was measured in the same manner as the average light transmittance at wavelengths of 350 to 460 nm described above. The following classifications were used for evaluation: A: 20.0% or more B: Less than 20.0%

[0066] <Glitter Evaluation> The glare of a lit blue LED was evaluated as follows when viewed through a film from a distance of 5 meters from the LED. The evaluation was conducted by five experts and decided by majority vote. The blue LED used was an ultra-high brightness bulb-type LED (manufactured by Elekit Co., Ltd.). A: No glare is perceived. B: Glare is perceived.

[0067] <b * Value > Regarding the obtained polycarbonate resin film, b * The values ​​were measured according to JIS Z 8781-4 using a spectrophotometer under the following conditions: Measurement method: Transmitted specular reflection processing: SCI Light source: D65 Field of view: 2° The spectrophotometer used was the "SD-7000" manufactured by Nippon Denshoku Industries Co., Ltd.

[0068]

[0069]

[0070] I in Tables 1 and 2 above 520 This is the absorption coefficient of the yellow dye at a wavelength of 520 nm, and its unit is 10. -9 The value is / ppm·μm. For example, the absorption coefficient of the yellow dye used in Example 1 at a wavelength of 520 nm is 4.3 × 10⁻¹⁶. -9 / ppm·μm. The I of the yellow dye 520 / I 460 [10 -3 Regarding ], for example, in Example 1, I 520 / I 460 1.0 × 10 -3 This is the result.

[0071] As is clear from the above results, the film of this embodiment was able to cut out light in the ultraviolet region, reduce the glare of the blue LED, and transmit light with a wavelength of 485 nm (Examples 1 to 5). In contrast, when the yellow dye and ultraviolet absorber were not included (Comparative Example 1), the glare of the blue LED could not be cut out. Furthermore, light in the ultraviolet region was also transmitted. 520 1.0 × 10 -7 When the concentration exceeded ppm·μm (Comparative Example 2), the glare of the blue LED was reduced, but light with a wavelength of 485 nm could not be transmitted. Also, when the yellow dye content was below the lower limit of the present invention (Comparative Example 3), the glare of the blue LED could not be reduced. Furthermore, light in the ultraviolet region was also transmitted. On the other hand, when the yellow dye content exceeded the upper limit of the present invention (Comparative Example 4), light with a wavelength of 485 nm could not be transmitted. Also, when no ultraviolet absorber was included (Comparative Example 5), light in the ultraviolet region could not be reduced.

[0072] Although the present invention has been described in detail using specific embodiments, it will be apparent to those skilled in the art that various modifications are possible without departing from the intent and scope of the invention.

[0073] 1. Lens 2. Polarizing film 3. Polarizing film substrate 4. Polarizing film substrate

Claims

1. A film comprising a polycarbonate resin, a yellow dye, and an ultraviolet absorber, wherein the yellow dye has an absorption coefficient (I) at a wavelength of 520 nm. 520 ) is 1.0 × 10 -7 A film having a particle size of 1 / ppm·μm or less, a content of the yellow dye per 100 parts by mass of the polycarbonate resin of 100 to 4000 ppm by mass, a content of the ultraviolet absorber of 0.01 to 1 part by mass, an average light transmittance of the film at a wavelength of 350 to 460 nm of 5.0% or less, and a light transmittance of the film at a wavelength of 485 nm of 20.0% or more.

2. The film according to claim 1, wherein the thickness of the film is 200 to 600 μm.

3. The yellow dye is defined as the ratio of the absorption coefficient at a wavelength of 520 nm to the absorption coefficient at a wavelength of 460 nm. 520 / I 460 3.0 x 10 -3 The film according to claim 1 or 2, which is as follows:

4. The film according to claim 1 or 2, wherein the yellow dye comprises at least one compound represented by formula (YP). Formula (YP) 5. The film according to claim 1 or 2, wherein the ultraviolet absorber comprises a compound represented by formula (UV-1). (In formula (UV-1), R 1 R is a group consisting of a hydrocarbon group having 1 to 10 carbon atoms, or a combination of a hydrocarbon group having 1 to 10 carbon atoms and -O- and / or -C(=O)-, 2 ~R 4 Each of these is independently a hydroxyl group, a hydrocarbon group having 1 to 10 carbon atoms, or a group consisting of a hydrocarbon group having 1 to 10 carbon atoms and -O- and / or -C(=O)-, where n2 is an integer from 0 to 3, and n3 and n4 are independently integers from 0 to 4.

6. The film according to claim 1 or 2, wherein the light transmittance at a wavelength of 460 nm is 3.0% or less.

7. The thickness of the film is 200 to 600 μm, and the yellow dye is I, which is the ratio of the absorption coefficient at a wavelength of 520 nm to the absorption coefficient at a wavelength of 460 nm 520 / I 460 is 3.0×10 -3 or less, the yellow dye contains at least one compound represented by the formula (YP), the ultraviolet absorber contains a compound represented by the formula (UV-1), and the light transmittance at a wavelength of 460 nm is 3.0% or less. The film according to claim 1. Formula (YP) (In the formula (UV-1), R 1 is a hydrocarbon group having 1 to 10 carbon atoms, or a group composed of a hydrocarbon group having 1 to 10 carbon atoms and a combination of -O- and / or -C(=O)-, and R 2 to R 4 are each independently a hydroxyl group, a hydrocarbon group having 1 to 10 carbon atoms, or a group composed of a hydrocarbon group having 1 to 10 carbon atoms and a combination of -O- and / or -C(=O)-, n2 is an integer of 0 to 3, and n3 and n4 are each independently an integer of 0 to 4.) 8. A multilayer having the film and polarizing film according to claim 1, 2, or 7.

9. The multilayer heat-bendable molded article according to claim 8.

Citation Information

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