阅读说明：本技术 树脂组合物、光学层、罩构件及移动体 (Resin composition, optical layer, cover member, and moving object ) 是由 船越雄一朗 于 2019-09-24 设计创作，主要内容包括：本发明的树脂组合物用于形成光学层(10)中的第二层,所述光学层具备：第一层即基材层(1),包含树脂材料和可见光吸收剂；及第二层即保护层(2),保护第一层,所述树脂组合物包含硅改性(甲基)丙烯酸树脂、氨基甲酸酯(甲基)丙烯酸酯及多官能(甲基)丙烯酸酯,并且满足下述要件A。要件A：在基材上形成了第二层时,在第二层上形成有包含45wt％以上的石油系溶剂的混合溶剂的涂膜的状态下静置之后,去除混合溶剂,然后通过划格法测得的切割为格子状的第二层相对于基材的附着性为95％以上。(The resin composition of the present invention is used for forming a second layer in an optical layer (10) which comprises: a first layer (substrate layer) (1) comprising a resin material and a visible light absorber; and a second layer (i.e., a protective layer (2) which protects the first layer, wherein the resin composition contains a silicon-modified (meth) acrylic resin, a urethane (meth) acrylate, and a polyfunctional (meth) acrylate, and satisfies the following requirement A. A key element A: when the second layer is formed on the base material, the second layer is left to stand in a state where a coating film containing a mixed solvent of 45 wt% or more of a petroleum-based solvent is formed on the second layer, and after removing the mixed solvent, the adhesion of the second layer cut into a lattice shape with respect to the base material as measured by a cross hatch method is 95% or more.)

1. A resin composition for forming a second layer in an optical layer, the optical layer comprising: a first layer including a resin material as a main material having light transmittance and a visible light absorber dispersed in the resin material and absorbing visible light; and the second layer for protecting the first layer, the resin composition being characterized in that,

contains a silicon-modified (meth) acrylic resin, a urethane (meth) acrylate and a polyfunctional (meth) acrylate, and satisfies the following requirement A,

a key element A: when the second layer having an average thickness of 12 μm is formed on a base material containing a bisphenol type polycarbonate resin as a main material, the second layer is allowed to stand at 85 ℃ for 24 hours in a state where a coating film containing a mixed solvent of a petroleum solvent in an amount of 45 wt% or more is formed on the second layer, and then is returned to an atmosphere of 25 ℃, after the mixed solvent is removed, the adhesion of the second layer cut into a lattice shape as measured by a cross-hatch method defined in JIS K5600-5-6 to the base material is 95% or more.

2. The resin composition according to claim 1, wherein the following condition B is satisfied,

a key element B: the second layer having an average thickness of 12 [ mu ] m is provided on a substrate having an average thickness of 2mm and made of a bisphenol type polycarbonate resin to form a laminate composed of the substrate and the second layer, the laminate is allowed to stand under conditions of 85 ℃ for 24 hours in a state where a coating film of the mixed solvent is formed on the second layer, and then is returned to an atmosphere of 25 ℃, and after the mixed solvent is removed, the transmittance (%) of the laminate at a wavelength of 900nm is measured, and the transmittance is 60% or more.

3. The resin composition according to claim 1 or 2, wherein,

the resin composition further contains an isocyanate.

4. The resin composition according to any one of claims 1 to 3, wherein,

the multifunctional (meth) acrylate comprises a tetrafunctional (meth) acrylate and an aromatic difunctional (meth) acrylate.

5. The resin composition according to any one of claims 1 to 4, wherein,

the urethane (meth) acrylate is an alicyclic urethane (meth) acrylate having a carbonate structure.

6. The resin composition according to any one of claims 1 to 4, wherein,

the resin composition further contains an ultraviolet absorber for absorbing ultraviolet rays.

7. The resin composition according to any one of claims 1 to 6, wherein,

the optical layer functions as a cover member having light transmittance.

8. An optical layer comprising:

the first layer; and

the second layer formed using the resin composition according to any one of claims 1 to 7.

9. The optical layer of claim 8,

the resin material contained in the first layer is a bisphenol polycarbonate-based resin.

10. The optical layer of claim 8 or 9,

the visible light absorber included in the first layer includes at least one of a first light absorber that absorbs light having a wavelength of 300nm or more and 550nm or less, a second light absorber that absorbs light having a wavelength of 450nm or more and 800nm or less, and a third light absorber that absorbs light having a wavelength of 400nm or more and 800nm or less.

11. The optical layer of any one of claims 8 to 10,

the first layer further contains an ultraviolet absorber that absorbs ultraviolet light.

12. A cover member comprising the optical layer according to any one of claims 8 to 11 as a cover member having light transmittance, which is provided to a movable body.

13. A movable body comprising the cover member according to claim 12.

Technical Field

The present invention relates to a resin composition for forming an optical layer, a cover member, and a moving body.

Background

Generally, a molded article made of a light-transmitting resin material is lightweight and excellent in moldability. In particular, molded articles made of polycarbonate resins are excellent in transparency and impact resistance as compared with glass products, and therefore are generally used for various lamp glasses, window materials, covers for instruments, windshields, and the like (see, for example, patent document 1).

Such a molded article can be used as a cover member provided in a moving body such as an automobile or a two-wheeled vehicle. Since these mobile bodies are used outdoors, a cover member having a hard coating layer (coating layer) formed by hard coating the surface of a molded article is used in order to make the cover member able to withstand a very severe environment such as sunlight and rain.

In order to be able to withstand harsh environments, the coating layer is required to have scratch resistance as an essential characteristic in terms of protecting the surface in addition to weather resistance and environmental resistance. Further, various properties such as flexibility (workability) are required for the coating layer depending on the application, and various studies have been made in recent years.

However, the conventional coating is exposed to chemicals such as petroleum solvents used for maintenance of the moving body depending on the environment in which the moving body is used, and the like, and there is a problem that the appearance of the coating is impaired when the coating is left in a state in which the chemicals are adhered to the coating.

Disclosure of Invention

Technical problem to be solved by the invention

The purpose of the present invention is to provide a resin composition capable of forming an optical layer as a cover member that reliably prevents or inhibits damage to the appearance even when exposed to chemicals such as petroleum solvents, an optical layer and a cover member formed using the resin composition, and a highly reliable moving body provided with the cover member.

Means for solving the technical problem

This object can be achieved by the present invention described in the following (1) to (13).

(1) A resin composition for forming a second layer in an optical layer, the optical layer comprising: a first layer including a resin material as a main material having light transmittance and a visible light absorber dispersed in the resin material and absorbing visible light; and the second layer for protecting the first layer, the resin composition being characterized in that,

contains a silicon-modified (meth) acrylic resin, a urethane (meth) acrylate, and a polyfunctional (meth) acrylate, and satisfies the following requirement A.

A key element A: when the second layer having an average thickness of 12 μm is formed on a base material containing a bisphenol type polycarbonate resin as a main material, the second layer is allowed to stand at 85 ℃ for 24 hours in a state where a coating film containing a mixed solvent of a petroleum solvent in an amount of 45 wt% or more is formed on the second layer, and then is returned to an atmosphere of 25 ℃, after the mixed solvent is removed, the adhesion of the second layer cut into a lattice shape as measured by a cross-hatch method defined in JIS K5600-5-6 to the base material is 95% or more.

(2) The resin composition according to the above (1), wherein the following requirement B is satisfied.

A key element B: the second layer having an average thickness of 12 [ mu ] m is provided on a substrate having an average thickness of 2mm and made of a bisphenol type polycarbonate resin to form a laminate composed of the substrate and the second layer, the laminate is allowed to stand under conditions of 85 ℃ for 24 hours in a state where a coating film of the mixed solvent is formed on the second layer, and then is returned to an atmosphere of 25 ℃, and after the mixed solvent is removed, the transmittance (%) of the laminate at a wavelength of 900nm is measured, and the transmittance is 60% or more.

(3) The resin composition according to the above (1) or (2), wherein the resin composition further contains an isocyanate.

(4) The resin composition according to any one of the above (1) to (3), wherein the polyfunctional (meth) acrylate comprises a tetrafunctional (meth) acrylate and an aromatic difunctional (meth) acrylate.

(5) The resin composition according to any one of the above (1) to (4), wherein the urethane (meth) acrylate is an alicyclic urethane (meth) acrylate having a carbonate structure.

(6) The resin composition according to any one of the above (1) to (4), further comprising an ultraviolet absorber that absorbs ultraviolet rays.

(7) The resin composition according to any one of the above (1) to (6), wherein the optical layer serves as a cover member having light transmittance.

(8) An optical layer comprising: the first layer; and the second layer, using the resin composition described in any one of (1) to (7) above to form.

(9) The optical layer according to the above (8), wherein the resin material contained in the first layer is a bisphenol polycarbonate-based resin.

(10) The optical layer according to the above (8) or (9), wherein the visible light absorber included in the first layer includes at least one of a first light absorber that absorbs light having a wavelength of 300nm or more and 550nm or less, a second light absorber that absorbs light having a wavelength of 450nm or more and 800nm or less, and a third light absorber that absorbs light having a wavelength of 400nm or more and 800nm or less.

(11) The optical layer according to any one of the above (8) to (10), wherein the first layer further contains an ultraviolet absorber that absorbs ultraviolet rays.

(12) A cover member characterized by comprising the optical layer according to any one of (8) to (11) above as a light-transmitting cover member provided to a movable body.

(13) A movable body comprising the cover member described in (12) above.

ADVANTAGEOUS EFFECTS OF INVENTION

The resin composition of the present invention is used for forming a second layer in an optical layer, the optical layer comprising: a first layer including a resin material as a main material having light transmittance and a visible light absorber dispersed in the resin material and absorbing visible light; and the second layer, protect this first layer.

In this resin composition, the resin composition of the present invention contains a silicon-modified (meth) acrylic resin, a urethane (meth) acrylate and a polyfunctional (meth) acrylate, and when the second layer having an average thickness of 12 μm is formed on a base material containing a bisphenol type polycarbonate resin as a main material, the second layer is allowed to stand at 85 ℃ for 24 hours in a state where a coating film containing a mixed solvent of a petroleum-based solvent of 45 wt% or more is formed on the second layer, and then is returned to an atmosphere of 25 ℃, and after removing the mixed solvent, the adhesion of the second layer cut into a lattice shape as measured by a cross hatch method defined in JIS K5600-5-6 to the base material is 95% or more. Therefore, the optical layer including the second layer can be used as a cover member that reliably prevents or suppresses the appearance from being damaged even if the second layer is exposed to chemicals such as petroleum solvents. Therefore, a moving body provided with the optical layer as a cover member has excellent reliability.

Drawings

Fig. 1 is a longitudinal sectional view showing a first embodiment of the optical layer of the present invention.

Fig. 2 is a longitudinal sectional view showing a second embodiment of the optical layer of the present invention.

Detailed Description

The resin composition, the optical layer, the cover member, and the mobile object of the present invention will be described in detail below with reference to preferred embodiments shown in the drawings.

The resin composition of the present invention is a resin composition for forming a second layer in an optical layer, the optical layer including: a first layer including a resin material as a main material having light transmittance and a visible light absorber dispersed in the resin material and absorbing visible light; and a second layer which protects the first layer, wherein the resin composition contains a silicon-modified (meth) acrylic resin, a urethane (meth) acrylate, and a polyfunctional (meth) acrylate, and satisfies the following requirement A.

A key element A: when the second layer having an average thickness of 12 μm is formed on a base material containing a bisphenol type polycarbonate resin as a main material, the second layer is allowed to stand at 85 ℃ for 24 hours in a state where a coating film containing a mixed solvent of a petroleum solvent in an amount of 45 wt% or more is formed on the second layer, and then is returned to an atmosphere of 25 ℃, after the mixed solvent is removed, the adhesion of the second layer cut into a lattice shape as measured by a cross-hatch method defined in JIS K5600-5-6 to the base material is 95% or more. Thus, according to the resin composition of the present invention, an optical layer having a second layer satisfying requirement a can be formed. Therefore, even if the optical layer is exposed to chemicals such as petroleum solvents, peeling of the second layer (protective layer) from the first layer (base material layer) in the optical layer can be reliably suppressed or prevented. Therefore, the optical layer can be used as a cover member that maintains an excellent appearance.

Hereinafter, before the resin composition, the optical layer, the cover member, and the moving body of the present invention are described, the optical layer of the present invention will be described.

< optical layer >

First embodiment

First, a first embodiment of the optical layer of the present invention will be explained.

Fig. 1 is a longitudinal sectional view showing a first embodiment of the optical layer of the present invention. For convenience of description, the upper side of fig. 1 is referred to as "upper" and the lower side is referred to as "lower".

The optical layer 10 (optical film) is applied to the cover member, and in the present embodiment, as shown in fig. 1, includes a base material layer 1 (first layer) and a protective layer 2 (second layer) laminated on the base material layer 1 and protecting the base material layer 1.

When the optical layer 10 is applied to the cover member, the optical layer 10 is provided so that the protective layer 2 faces outward and the base layer 1 covers the object. This enables the protective layer 2 (hard coat layer) to function as a protective layer for the protective substrate layer 1.

The base material layer 1 (first layer) includes a resin material as a main material having light transmittance and a visible light absorber dispersed in the resin material and absorbing visible light. Thereby, the base material layer 1 has a function of allowing transmission of light having a desired wavelength region by suppressing or preventing transmission of visible light in a specific wavelength region.

Since the optical layer 10 includes the base material layer 1, the optical layer 10 (cover member) exhibits light-blocking properties for blocking light in a specific wavelength region. Thus, the optical layer 10 exhibits light transmittance for transmitting light having a desired wavelength range. Therefore, the optical layer 10 can be used as a cover member that allows light having a desired color tone to be transmitted.

The resin material (base resin) is included as a main material of the base material layer 1, and is used for molding the base material layer 1 into a substrate shape.

The resin material is not particularly limited as long as it is a material having light transmittance, and examples thereof include acrylic resins, polystyrene resins, polyethylene resins, polypropylene resins, polyester resins such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), polycarbonate resins, vinyl chloride resins, polyacetal resins, and the like, and one or two or more of these resins may be used in combination. Among these, polycarbonate-based resins are particularly preferable. Since the polycarbonate-based resin is rich in transparency (light transmittance) and mechanical strength such as rigidity and impact resistance, the transparency of the resin material of the optical layer 10 and the mechanical strength of the optical layer 10 can be improved by using the polycarbonate-based resin as the resin material. Further, since the polycarbonate-based resin has a specific gravity of about 1.2 and is classified as a light material among resin materials, the optical layer 10 can be reduced in weight by using the polycarbonate-based resin as the resin material.

As the polycarbonate-based resin, various polycarbonate resins having various molecular structures can be used, and among them, bisphenol-based polycarbonate-based resins are preferable. The bisphenol polycarbonate resin has benzene rings in its main chain, and thus the optical layer 10 has more excellent strength.

The bisphenol polycarbonate resin is synthesized, for example, by an interfacial polycondensation reaction between bisphenol and phosgene, an ester exchange reaction between bisphenol and diphenyl carbonate, or the like.

Examples of the bisphenol include bisphenol a and bisphenol (modified bisphenol) which is a source of a repeating unit of a polycarbonate represented by the following formula (a).

(in the formula (A), X is C1-18 alkyl, aromatic group or cyclic aliphatic group, Ra and Rb are independently C1-12 alkyl, m and n are integers of 0-4, and p is the number of repeating units.)

Specific examples of the bisphenol to be a source of the repeating unit of the polycarbonate represented by the formula (A) include 4,4 '- (pentane-2, 2-diyl) diphenol, 4' - (pentane-3, 3-diyl) diphenol, 4 '- (butane-2, 2-diyl) diphenol, 1' - (cyclohexanediyl) diphenol, 2-cyclohexyl-1, 4-bis (4-hydroxyphenyl) benzene, 2, 3-dicyclohexyl-1, 4-bis (4-hydroxyphenyl) benzene, 1 '-bis (4-hydroxy-3-methylphenyl) cyclohexane, and 2, 2' -bis (4-hydroxy-3-methylphenyl) propane, one of these or two or more of these can be used in combination.

The content of the resin material in the optical layer 10 is not particularly limited, but is preferably 75 wt% or more, and more preferably 85 wt% or more. When the content of the resin material is within the above range, the optical layer 10 can exhibit excellent strength.

The visible light absorber is a material that suppresses or prevents transmission of visible light in a specific wavelength region. By substantially uniformly containing the visible light absorbing material in a state of being dispersed in the base material layer 1, a function of allowing light having a desired wavelength region to transmit is provided to the base material layer 1.

Such a visible light absorber is not particularly limited, and examples thereof include a first light absorber that absorbs light having a wavelength of 300nm or more and 550nm or less, a second light absorber that absorbs light having a wavelength of 450nm or more and 800nm or less, and a third light absorber that absorbs light having a wavelength of 400nm or more and 800nm or less, and by appropriately setting the combination of these and the content thereof, a function of allowing light having a desired wavelength region to pass through can be reliably provided to the base layer 1. Therefore, the optical layer 10 (cover member) exhibits light transmittance for transmitting light having a desired wavelength range.

The first light absorber has an absorption wavelength characteristic of absorbing light having a wavelength of 300nm or more and 550nm or less. Examples of the first light absorber include quinoline pigments.

Examples of the quinoline-based coloring matter include alkyl-substituted quinoline compounds such as 2-methylquinoline, 3-methylquinoline, 4-methylquinoline, 6-methylquinoline, 7-methylquinoline, 8-methylquinoline, 6-isopropylquinoline, 2, 4-dimethylquinoline, 2, 6-dimethylquinoline and 4,6, 8-trimethylquinoline, amino-substituted quinoline compounds such as 2-aminoquinoline, 3-aminoquinoline, 5-aminoquinoline, 6-aminoquinoline, 8-aminoquinoline and 6-amino-2-methylquinoline, alkoxy-substituted quinoline compounds such as 6-methoxy-2-methylquinoline and 6, 8-dimethoxy-4-methylquinoline, 6-chloroquinoline, 6-methylquinoline, 4-methylquinoline, and the like, And halogen-substituted quinoline compounds such as 4, 7-dichloroquinoline, 3-bromoquinoline and 7-chloro-2-methylquinoline, and one or more of these compounds can be used.

By blending such a first light absorber as a visible light absorber, light having a wavelength of 300nm or more and 550nm or less among light incident on the base layer 1 can be reliably absorbed in the base layer 1.

The content of the first light absorber in the base layer 1 is not particularly limited, but is preferably 0.001 wt% or more and 10 wt% or less, more preferably 0.002 wt% or more and 1.0 wt% or less, and further preferably 0.005 wt% or more and 0.3 wt% or less. If the content of the first light absorber in the base material layer 1 is less than the lower limit, the absorption of visible light (light having a wavelength of 300nm or more and 550nm or less) in the base material layer 1 may be reduced depending on the type of the first light absorber. Even if the content of the first light absorber in the base material layer 1 exceeds the upper limit, no improvement in the absorption of visible light (light having a wavelength of 300nm or more and 550nm or less) of the content is observed, and there is a possibility that the adhesion of the base material layer 1 to the protective layer 2 is impaired.

The second light absorber has an absorption wavelength characteristic of absorbing light having a wavelength of 450nm or more and 800nm or less. The second light absorber includes, for example, an anthraquinone dye.

Examples of the anthraquinone-based coloring matter include (1) 2-anilino-1, 3, 4-trifluoroanthraquinone, (2)2- (o-ethoxycarbonylanilino) -1,3, 4-trifluoroanthraquinone, (3)2- (p-ethoxycarbonylanilino) -1,3, 4-trifluoroanthraquinone, (4)2- (m-ethoxycarbonylanilino) -1,3, 4-trifluoroanthraquinone, (5)2- (o-cyanoanilino) -1,3, 4-trifluoroanthraquinone, (6)2- (p-cyanoanilino) -1,3, 4-trifluoroanthraquinone, (7)2- (m-cyanoanilino) -1,3, 4-trifluoroanthraquinone, (8)2- (o-nitroanilino) -1,3, 4-trifluoroanthraquinone, (9)2- (p-nitroanilino) -1,3, 4-trifluoroanthraquinone, (10)2- (m-nitroanilino) -1,3, 4-trifluoroanthraquinone, (11)2- (p-tert-butylanilino) -1,3, 4-trifluoroanthraquinone, (12)2- (o-methoxyanilino) -1,3, 4-trifluoroanthraquinone, (13)2- (2, 6-diisopropylanilino) -1,3, 4-trifluoroanthraquinone, (14)2- (2, 6-dichloroanilino) -1,3, 4-trifluoroanthraquinone, (15)2- (2, 6-difluoroanilino) -1,3, 4-trifluoroanthraquinone, (16)2- (3, 4-dicyanoanilino) -1,3, 4-trifluoroanthraquinone, (17)2- (2,4, 6-trichloroanilino) -1,3, 4-trifluoroanthraquinone, (18)2- (2,3,5, 6-tetrachloroanilino) -1,3, 4-trifluoroanthraquinone, (19)2- (2,3,5, 6-tetrafluoroanilino) -1,3, 4-trifluoroanthraquinone, (20)3- (2,3,4, 5-tetrafluoroanilino) -2-butoxy-1, 4-difluoroanthraquinone, (21)3- (4-cyano-3-chloroanilino) -2-octyloxy-1, 4-difluoroanthraquinone, (22)3- (3, 4-dicyanoanilino) -2-hexyloxy-1, 4-difluoroanthraquinone, (23)3- (4-cyano-3-chloroanilino) -1, 2-dibutoxy-4-fluoroanthraquinone, (24)3- (p-cyanoanilino) -2-phenoxy-1, 4-difluoroanthraquinone, (25)3- (p-cyanoanilino) -2- (2, 6-diethylphenoxy) -1, 4-difluoroanthraquinone, (26)3- (2, 6-dichloroanilino) -2- (2, 6-dichlorophenoxy) -1, 4-difluoroanthraquinone, (27)3- (2,3,5, 6-tetrachloroanilino) -2- (2, 6-dimethoxyphenoxy) -1, 4-difluoroanthraquinone, a salt thereof, a base, a stabilizer, (28)2, 3-dianilino-1, 4-difluoroanthraquinone, (29)2, 3-bis (p-tert-butylanilino) -1, 4-difluoroanthraquinone, (30)2, 3-bis (p-methoxyanilino) -1, 4-difluoroanthraquinone, (31)2, 3-bis (2-methoxy-6-methylanilino) -1, 4-difluoroanthraquinone, (32)2, 3-bis (2, 6-diisopropylanilino) -1, 4-difluoroanthraquinone, (33)2, 3-bis (2,4, 6-trichloroanilino) -1, 4-difluoroanthraquinone, (34)2, 3-bis (2,3,5, 6-tetrachloroanilino) -1, 4-difluoroanthraquinone, (35)2, 3-bis (2,3,5, 6-tetrafluoroanilino) -1, 4-difluoroanthraquinone, (36)2, 3-bis (p-cyanoanilino) -1-methoxyethoxy-4-fluoroanthraquinone, (37)2- (2, 6-dichloroanilino) -1,3, 4-trichloroanthraquinone, (38)2- (2,3,5, 6-tetrafluoroanilino) -1,3, 4-trichloroanthraquinone, (39)3- (2, 6-dichloroanilino) -2- (2, 6-dichlorophenoxy) -1, 4-dichloroanthraquinone, (40)2- (2, 6-dichloroanilino) anthraquinone, (41)2- (2,3,5, 6-tetrafluoroanilino) anthraquinone, (42)3- (2, 6-dichloroanilino) -2- (2, 6-dichlorophenoxy) anthraquinone, (43)2, 3-bis (2-methoxy-6-methylanilino) -1, 4-dichloroanthraquinone, (44)2, 3-bis (2, 6-diisopropylanilino) anthraquinone, (45) 2-butylamino-1, 3, 4-trifluoroanthraquinone, (46)1, 4-bis (n-butylamino) -2, 3-difluoroanthraquinone, (47)1, 4-bis (n-octylamino) -2, 3-difluoroanthraquinone, (48)1, 4-bis (hydroxyethylamino) -2, 3-difluoroanthraquinone, (49)1, 4-bis (cyclohexylamino) -2, 3-difluoroanthraquinone, (50)1, 4-bis (cyclohexylamino) -2-octyloxy-3-fluoroanthraquinone, (51)1,2, 4-tris (2, 4-dimethoxyphenoxy-3-fluoroanthraquinone, (52)2, 3-bis (phenylthio) -1-phenoxy-4-fluoroanthraquinone, and (53)1,2,3, 4-tetrakis (p-methoxyphenoxy) -anthraquinone, and one or a combination of two or more of these can be used.

By blending such a second light absorber as a visible light absorber, light having a wavelength of 450nm or more and 800nm or less among light incident on the base layer 1 can be reliably absorbed in the base layer 1.

The content of the second light absorber in the base layer 1 is not particularly limited, but is preferably 0.001 wt% or more and 10 wt% or less, more preferably 0.002 wt% or more and 1.0 wt% or less, and further preferably 0.005 wt% or more and 0.6 wt% or less. If the content of the second light absorber in the base material layer 1 is less than the lower limit, the absorption of visible light (light having a wavelength of 450nm or more and 800nm or less) in the base material layer 1 may be reduced depending on the type of the second light absorber. Even if the content of the second light absorber in the base material layer 1 exceeds the upper limit, no improvement in the absorption of visible light (light having a wavelength of 450nm or more and 800nm or less) of the content is observed, and the adhesion of the base material layer 1 to the protective layer 2 may be impaired.

The third light absorber has an absorption wavelength characteristic of absorbing light having a wavelength of 400nm or more and 800nm or less. Examples of the third light absorber include perinone-based pigments.

Examples of the perinone-based coloring matter include 2, 3-naphthalocyanine (naphthaloylone), 1, 8-naphthalocyanine-perinone, and tetrabromo-1, 2-naphthalocyanine-perinone, and one of these or two or more of these can be used in combination.

By incorporating such a perinone-based dye, light having a wavelength of 400nm or more and 800nm or less among light entering the substrate layer 1 can be reliably absorbed in the substrate layer 1.

The content of the third light absorber in the base layer 1 is not particularly limited, but is preferably 0.001 wt% or more and 10 wt% or less, more preferably 0.002 wt% or more and 1.0 wt% or less, and further preferably 0.005 wt% or more and 0.6 wt% or less. If the content of the third light absorber in the base material layer 1 is less than the lower limit, the absorption of visible light (light having a wavelength of 400nm or more and 800nm or less) in the base material layer 1 may be reduced depending on the type of the third light absorber. Even if the content of the third light absorber in the base material layer 1 exceeds the upper limit, no improvement in the absorption of visible light (light having a wavelength of 400nm or more and 800nm or less) of the third light absorber or more is observed, and the adhesion of the base material layer 1 to the protective layer 2 may be impaired.

The base layer 1 preferably contains an ultraviolet absorber in addition to the visible light absorber. This can reliably prevent or suppress deterioration of the resin material and the visible light absorber contained in the base material layer 1 and the object to be covered with the optical layer 10 (cover member) due to ultraviolet rays. Therefore, the base material layer 1 has excellent weather resistance.

The ultraviolet absorber is not particularly limited, but preferably includes a fourth light absorber that absorbs light having a wavelength of 100nm or more and 400nm or less. This can suppress the transmission of light having a relatively short wavelength (light having a wavelength of 400nm or less) of ultraviolet light and visible light. Therefore, the function as an ultraviolet absorber can be reliably exhibited.

The fourth light absorber (ultraviolet absorber) is not particularly limited, and examples thereof include triazine compounds, benzophenone compounds, benzotriazole compounds, and cyanoacrylate compounds, and one of these compounds or a combination of two or more of these compounds can be used. Among these, triazine compounds are particularly preferable. This can more reliably prevent or suppress deterioration of the base material layer 1 by ultraviolet rays, and can further improve the weather resistance of the optical layer 10.

Examples of the triazine compound include 2-mono (hydroxyphenyl) -1,3, 5-triazine compounds, 2, 4-bis (hydroxyphenyl) -1,3, 5-triazine compounds, and 2,4, 6-tris (hydroxyphenyl) -1,3, 5-triazine compounds, and specific examples thereof include 2, 4-diphenyl-6- (2-hydroxy-4-methoxyphenyl) -1,3, 5-triazine, 2, 4-diphenyl-6- (2-hydroxy-4-ethoxyphenyl) -1,3, 5-triazine, 2, 4-diphenyl- (2-hydroxy-4-propoxyphenyl) -1,3, 5-triazine, and, 2, 4-diphenyl- (2-hydroxy-4-butoxyphenyl) -1,3, 5-triazine, 2, 4-diphenyl-6- (2-hydroxy-4-hexyloxyphenyl) -1,3, 5-triazine, 2, 4-diphenyl-6- (2-hydroxy-4-octyloxyphenyl) -1,3, 5-triazine, 2, 4-diphenyl-6- (2-hydroxy-4-dodecyloxyphenyl) -1,3, 5-triazine, 2, 4-diphenyl-6- (2-hydroxy-4-benzyloxyphenyl) -1,3, 5-triazine, 2, 4-diphenyl-6- (2-hydroxy-4-butoxyethoxy) -1,3, 5-triazine, 2, 4-bis (2-hydroxy-4-butoxyphenyl) -6- (2, 4-dibutoxyphenyl) -1, 3-5-triazine, 2,4, 6-tris (2-hydroxy-4-methoxyphenyl) -1,3, 5-triazine, 2,4, 6-tris (2-hydroxy-4-ethoxyphenyl) -1,3, 5-triazine, 2,4, 6-tris (2-hydroxy-4-propoxyphenyl) -1,3, 5-triazine, 2,4, 6-tris (2-hydroxy-4-butoxyphenyl) -1,3, 5-triazine, 2,4, 6-tris (2-hydroxy-4-hexyloxyphenyl) -1,3, 5-triazine, 2,4, 6-tris (2-hydroxy-4-octyloxyphenyl) -1,3, 5-triazine, 2,4, 6-tris (2-hydroxy-4-dodecyloxyphenyl) -1,3, 5-triazine, 2,4, 6-tris (2-hydroxy-4-benzyloxyphenyl) -1,3, 5-triazine, 2,4, 6-tris (2-hydroxy-4-ethoxyethoxyphenyl) -1,3, 5-triazine, 2,4, 6-tris (2-hydroxy-4-butoxyethoxyphenyl) -1,3, 5-triazine, 2,4, 6-tris (2-hydroxy-4-propoxyethoxyphenyl) -1,3, 5-triazine, 2,4, 6-tris (2-hydroxy-4-methoxycarbonylpropoxyphenyl) -1,3, 5-triazine, 2,4, 6-tris (2-hydroxy-4-ethoxycarbonylethoxyphenyl) -1,3, 5-triazine, 2,4, 6-tris (2-hydroxy-4- (1- (2-ethoxyhexyloxy) -1-oxopropan-2-yloxy) phenyl) -1,3, 5-triazine, 2,4, 6-tris (2-hydroxy-3-methyl-4-methoxyphenyl) -1,3, 5-triazine, 2,4, 6-tris (2-hydroxy-3-methyl-4-ethoxyphenyl) -1,3, 5-triazine, 2,4, 6-tris (2-hydroxy-3-methyl-4-propoxyphenyl) -1,3, 5-triazine, 2,4, 6-tris (2-hydroxy-3-methyl-4-butoxyphenyl) -1,3, 5-triazine, 2,4, 6-tris (2-hydroxy-3-methyl-4-hexyloxyphenyl) -1,3, 5-triazine, 2,4, 6-tris (2-hydroxy-3-methyl-4-octyloxyphenyl) -1,3, 5-triazine, 2,4, 6-tris (2-hydroxy-3-methyl-4-dodecyloxyphenyl) -1,3, 5-triazine, 2,4, 6-tris (2-hydroxy-3-methyl-4-benzyloxyphenyl) -1,3, 5-triazine, 2,4, 6-tris (2-hydroxy-3-methyl-4-ethoxyethoxyethoxyphenyl) -1,3, 5-triazine, 2,4, 6-tris (2-hydroxy-3-methyl-4-butoxyethoxyphenyl) -1,3, 5-triazine, 2,4, 6-tris (2-hydroxy-3-methyl-4-propoxyethoxyphenyl) -1,3, 5-triazine, 2,4, 6-tris (2-hydroxy-3-methyl-4-methoxycarbonylpropoxyphenyl) -1,3, 5-triazine, 2,4, 6-tris (2-hydroxy-3-methyl-4-ethoxycarbonylethoxyphenyl) -1,3, 5-triazine, 2,4, 6-tris (2-hydroxy-3-methyl-4- (1- (2-ethoxyhexyloxy) -1-oxopropan-2-yloxy) phenyl) -1,3, 5-triazine, and the like. Examples of commercially available triazine-based ultraviolet absorbers include "Tinuvin 1577", "Tinuvin 460", "Tinuvin 477" (manufactured by BASF Japan ltd.) "adekasab LA-F70" (manufactured by adakacorporation), and one of these or two or more of these can be used in combination.

By incorporating such a fourth light absorber, light having a wavelength of 100nm or more and 400nm or less among light entering the base layer 1 can be reliably absorbed in the base layer 1.

When the substrate layer 1 contains the fourth light absorber, the content of the fourth light absorber in the substrate layer 1 is not particularly limited, but is preferably 0.1 wt% or more and 24 wt% or less, and more preferably 0.1 wt% or more and 10 wt% or less. If the content of the fourth light absorber in the base material layer 1 is less than the lower limit, the weather resistance of the base material layer 1 may be reduced depending on the type of the first light absorber. Even if the content of the fourth light absorber in the base material layer 1 exceeds the upper limit, the weather resistance is not improved more than that, and adhesion of the base material layer 1 to the protective layer 2 may be impaired.

The base layer 1 may contain a pigment (e.g., an infrared absorber) different from the visible light absorber and the ultraviolet absorber listed above. The coloring matter is not particularly limited, and examples thereof include pigments and dyes, and these can be used alone or in combination.

The pigment is not particularly limited, and examples thereof include phthalocyanine pigments such as phthalocyanine green and phthalocyanine blue, fast yellow, disazo yellow, condensed azo yellow, benzimidazolone yellow, dinitroaniline orange, benzimidazolone orange, toluidine red, permanent magenta, permanent red, naphthol red, condensed azo red, benzimidazolone magenta and benzimidazolone brown, anthraquinone pigments such as anthraquinone pyrimidine yellow and anthraquinone red, azomethine pigments such as copper azomethine yellow, quinophthalone pigments such as quinophthalone yellow, isoindoline pigments such as isoindoline yellow, nitroso pigments such as nickel dioxime yellow, perinone pigments such as perinone orange, quinacridone magenta, quinacridone red, quinacridone scarlet and quinacridone red, perylene red and perylene red, perylene pigments such as diketopyrrolopyrrole red, pyrrolopyrrole pigments such as diketopyrrolopyrrole red, perylene pigments, and perylene pigments, Organic pigments such as dioxazine violet; carbon-based pigments such as carbon black, lamp black, furnace black, ivory black, graphite, and fullerene, chromate-based pigments such as chrome yellow and molybdate orange, sulfide-based pigments such as cadmium yellow, cadmium zinc barium white yellow, cadmium orange, cadmium zinc barium white orange, vermilion, cadmium red, cadmium zinc barium white red, and sulfide, yellow brown (ocher), titanium yellow, titanium barium nickel yellow, iron oxide red (bengala), and red lead, amber (amber), iron oxide brown, zinc iron chromium brown, chromium oxide, cobalt green, cobalt chromium green, titanium cobalt green, cobalt blue, cyan blue, cobalt aluminum chromium blue, iron black, manganese ferrite black, cobalt ferrite black, copper chromium manganese black, etc., chromium green, etc., iron blue, Berlin blue, etc., ultramarine blue, etc., cobalt violet, mineral violet, etc., phosphate pigment, other (for example, cadmium sulfide, cadmium selenide, etc.), etc., and one or more of these may be used in combination.

The dye is not particularly limited, and examples thereof include a metal complex dye, a cyan dye, a xanthene dye, an azo dye, a hibiscus dye, a blackberry dye, a raspberry dye, a pomegranate fruit juice dye, and a chlorophyll dye, and one of these dyes or a combination of two or more thereof can be used.

By appropriately setting the combination of the visible light absorber, the ultraviolet absorber, and the different types of pigments, and further appropriately setting the content thereof, the substrate layer 1 can be made to exhibit a function of selectively allowing light having a desired wavelength region to transmit therethrough.

The protective layer 2 is laminated on the base material layer 1 to cover the base material layer 1, thereby functioning as a hard coat layer (coating layer) for protecting the base material layer 1.

The protective layer 2 is composed of a second layer formed using the resin composition of the present invention.

The resin composition of the present invention comprises a silicon-modified (meth) acrylic resin, a urethane (meth) acrylate, and a polyfunctional (meth) acrylate. As a result, the optical layer 10 including the protective layer 2 composed of the second layer has excellent weather resistance, durability, scratch resistance, and thermoformability, and particularly satisfies the following requirement a.

A key element A: when the second layer having an average thickness of 12 μm is formed on a base material containing a bisphenol type polycarbonate resin as a main material, the second layer is allowed to stand at 85 ℃ for 24 hours in a state where a coating film containing a mixed solvent of a petroleum solvent in an amount of 45 wt% or more is formed on the second layer, and thereafter is returned to an atmosphere of 25 ℃ to remove the mixed solvent, and the adhesion of the second layer cut into a lattice shape as measured by a cross-hatch method defined in JIS K5600-5-6 to the base material is 95% or more.

As described above, according to the resin composition of the present invention, the optical layer 10 in which the protective layer 2 composed of the second layer satisfying the requirement a is formed on the base layer 1 can be obtained. Therefore, when the optical layer 10 is applied to a cover member provided in a brake lamp or a hazard lamp provided in a moving body such as an automobile or a two-wheeled vehicle, for example, even if the cover member is exposed to chemicals such as petroleum solvents contained in lubricants and rust inhibitors used for maintenance of the moving body, the peeling of the protective layer 2 (second layer) from the base material layer 1 (base material) in the optical layer 10 (cover member) is reliably suppressed or prevented. Therefore, the optical layer 10 suitable for the cover member can maintain excellent appearance. Therefore, it is possible to reliably suppress or prevent the change in characteristics such as the visibility of the optical layer 10 and the light transmittance allowing the light transmission in the specific wavelength region.

Hereinafter, various constituent materials included in the resin composition of the present invention for forming the protective layer 2 (second layer) will be described.

Here, by including the silicon-modified (meth) acrylic resin in the resin composition, it is possible to achieve an increase in the surface hardness of the protective layer 2. Therefore, excellent durability and scratch resistance can be imparted to the optical layer 10 including the protective layer 2.

Further, by including urethane (meth) acrylate in the resin composition, it is possible to improve flexibility of the protective layer 2. Therefore, it is possible to suppress the occurrence of cracks on the surface of the protective layer 2 when the optical layer 10 is thermally bent, and to impart excellent thermoformability to the optical layer 10.

In addition, by including a polyfunctional (meth) acrylate in the resin composition, it is possible to improve chemical resistance of the protective layer 2 against chemicals such as petroleum solvents. Therefore, the protective layer 2 satisfies the requirement a. Therefore, the optical layer 10 including the protective layer 2 can be provided with excellent chemical resistance against chemicals such as petroleum solvents. Further, the surface hardness of the protective layer 2 can be improved. Therefore, excellent durability and scratch resistance can be imparted to the optical layer 10 including the protective layer 2.

By combining the silicon-modified (meth) acrylic resin, the urethane (meth) acrylate, and the polyfunctional (meth) acrylate, the optical layer 10 satisfying the requirement a can be obtained while achieving both excellent scratch resistance and thermoformability.

The silicon-modified (meth) acrylic resin is a polymer (prepolymer) having a main chain in which a structural unit derived from a (meth) acrylic monomer having a (meth) acryloyl group is repeated, and a repeating body which is linked to the main chain and in which a structural unit having a siloxane bond is repeated.

The silicon-modified (meth) acrylic resin has the main chain to impart transparency to the protective layer 2, and contains a repeating body in which structural units having siloxane bonds are repeated to impart scratch resistance to the protective layer 2.

Specifically, the main chain of the silicon-modified (meth) acrylic resin includes a structure composed of a repeat of a structural unit derived from a monomer having a (meth) acryloyl group, which is represented by at least one of the following formulae (1) and (2).

(in the formula (1), n represents an integer of 1 or more, R1 independently represents a hydrocarbon group, an organic group or a hydrogen atom, and R0 independently represents a hydrocarbon group or a hydrogen atom.)

(in the formula (2), m represents an integer of 1 or more, R2 independently represents a hydrocarbon group, an organic group or a hydrogen atom, and R0 independently represents a hydrocarbon group or a hydrogen atom.)

Further, it is preferable to have a hydroxyl group (-OH) at the end of the main chain or in the side chain. That is, in the case of the formula (1) or the formula (2), it is preferable that R1 or R2 is hydrogen. Thus, when a polycarbonate-based resin is used as the resin material included in the base layer 1, the adhesion between the protective layer 2 and the base layer 1 can be improved. Therefore, the protective layer 2 can be reliably suppressed or prevented from being unintentionally peeled from the base material layer 1. When the resin composition contains an isocyanate described later, the hydroxyl group reacts with an isocyanate group of the curing agent to form a crosslinked structure based on a urethane bond. Therefore, the protective layer 2 can be densified, and chemical resistance against chemicals such as petroleum solvents is improved, so that the protective layer 2 reliably satisfies the requirement a.

And a repeating body in which a structural unit having a siloxane bond is repeated is bonded to at least one end of the main chain or a side chain.

Since the siloxane bond has a high bonding force, the protective layer 2 having further excellent heat resistance and weather resistance can be obtained by the silicon-modified (meth) acrylic resin containing a repeating body in which the structural units having siloxane bonds are repeated. Further, since the bonding force of the siloxane bond is high, the hard protective layer 2 can be obtained. Therefore, when the optical layer 10 is applied to a cover member of a brake lamp or a hazard lamp provided in a moving object such as an automobile or a two-wheeled vehicle, the abrasion resistance of the optical layer 10 against impact of sand dust, flying stones, or the like can be further improved.

Specifically, the repeating body in which the structural unit having a siloxane bond is repeated includes a repeating structure of a structural unit having a siloxane bond of at least one of the following formulae (3) and (4).

(in the formula (3), X1 represents a hydrocarbon group or a hydroxyl group.)

(in the formula (4), X2 represents a hydrocarbon group or a hydroxyl group, and X3 represents a divalent group wherein hydrogen is separated from the hydrocarbon group or the hydroxyl group.)

Specific examples of the repeating body in which the structural unit having a siloxane bond is repeated include a structure having polyorganosiloxane and a structure having silsesquioxane. The silsesquioxane may have any structure such as a random structure, a cage structure, or a ladder structure (ladder structure).

Examples of the hydrocarbon group include an alkyl group such as a methyl group, an ethyl group, a propyl group, and an isopropyl group, a cycloalkyl group such as a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, and a cyclohexyl group, an aryl group such as a phenyl group, a naphthyl group, and a 2-methylphenyl group, an aralkyl group such as a benzyl group, a diphenylmethyl group, and a naphthylmethyl group, a phenyl group, and a biphenyl group.

It is preferable that an unsaturated double bond is introduced to a terminal or a side chain of a repeating body in which a structural unit having a siloxane bond is repeated. Thereby, a network of the silicon-modified (meth) acrylic resin and the urethane (meth) acrylate can be formed by bonding to the (meth) acryloyl group of the urethane (meth) acrylate. Therefore, the silicon-modified (meth) acrylic resin and the urethane (meth) acrylate are more uniformly dispersed in the protective layer 2, and as a result, the protective layer 2 can more uniformly exhibit the above-described characteristics in the entire layer.

The content of the silicon-modified (meth) acrylic resin in the resin composition is not particularly limited, but is preferably 7 wt% or more and 15 wt% or less, more preferably 8.5 wt% or more and 15 wt% or less, and further preferably 10 wt% or more and 14 wt% or less, in a main resin (main resin) described later.

If the content of the silicon-modified (meth) acrylic resin in the resin composition is less than the lower limit value, the hardness of the protective layer 2 obtained from the resin composition may decrease depending on the type of the silicon-modified (meth) acrylic resin. When the content of the silicon-modified (meth) acrylic resin in the resin composition exceeds the upper limit, the content of the material other than the silicon-modified (meth) acrylic resin in the resin composition is relatively decreased, and as a result, the flexibility of the protective layer 2 formed using the resin composition may be decreased.

Urethane (meth) acrylate is a compound having a main chain having a urethane bond (-OCONH-) and a (meth) acryloyl group bonded to the main chain. And, the urethane (meth) acrylate is a monomer or oligomer.

Urethane (meth) acrylate is a compound having excellent flexibility because it has a urethane bond. Therefore, when the protective layer 2 contains urethane (meth) acrylate, further flexibility (flexibility) can be imparted to the protective layer 2.

Therefore, when the optical layer 10 is molded into a curved shape, the occurrence of cracks in the curved portion can be reliably suppressed or prevented.

The number of (meth) acryloyl groups in one molecule of the urethane (meth) acrylate is preferably two or more.

When the number of (meth) acryloyl groups in one molecule of the urethane (meth) acrylate is two or more, the urethane (meth) acrylate and the silicon-modified (meth) acrylic resin are bonded to form a network. Therefore, when the protective layer 2 is formed from the resin composition, curing of the protective layer 2 can be promoted. This can increase the crosslinking density of the protective layer 2, and thus can increase the hardness of the protective layer 2 to some extent. Therefore, the scratch resistance, chemical resistance, and other properties of the protective layer 2 can be achieved. Therefore, the protective layer 2 that reliably satisfies the requirement a can be produced.

The urethane (meth) acrylate can be obtained as a reaction product of an isocyanate compound obtained by reacting a polyol with a diisocyanate and a (meth) acrylate monomer having a hydroxyl group.

Examples of the polyol include polyether polyol, polyester polyol and polycarbonate diol.

The polyether polyol is preferably polyethylene oxide, polypropylene oxide, ethylene oxide-propylene oxide random copolymer and has a number average molecular weight of less than 1300. When the polyether polyol having a number average molecular weight of 1300 or more is used, the flexibility of the protective layer 2 becomes too high, and there is a possibility that scratches and the like are easily generated on the protective layer 2 (cover member) by the impact of, for example, sand dust, flying stones and the like.

The polyester polyol can be obtained, for example, by subjecting a diol and a dicarboxylic acid or dicarboxylic acid chloride to a polycondensation reaction or esterifying a diol or dicarboxylic acid to cause an ester exchange reaction. As the dicarboxylic acid, adipic acid, succinic acid, glutaric acid, pimelic acid, sebacic acid, azelaic acid, maleic acid, terephthalic acid, isophthalic acid, phthalic acid, and the like are used, and as the diol, ethylene glycol, 1, 4-butanediol, 1, 6-hexanediol, diethylene glycol, dipropylene glycol, triethylene glycol, tetraethylene glycol, tripropylene glycol, tetrapropylene glycol, and the like are used.

As the polycarbonate diol, 1, 4-butanediol, 1, 6-hexanediol, ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, 1, 2-propanediol, 1, 3-propanediol, dipropylene glycol, 2-ethyl-1, 3-hexanediol, 1, 5-pentanediol, 3-methyl-1, 5-pentanediol, 1, 4-cyclohexanediol, polyoxyethylene glycol, and the like are used, and one kind or two or more kinds may be used at the same time.

Examples of the acrylate monomer having a hydroxyl group include trimethylolpropane triacrylate, pentaerythritol triacrylate, dipentaerythritol triacrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxybutyl acrylate, 3-hydroxybutyl acrylate, and polyethylene glycol monoacrylate.

The weight average molecular weight of the urethane (meth) acrylate is not particularly limited, but is preferably 1.0 × 10³Above and 1.5 × 10⁴Hereinafter, more preferably 1.5 × 10³Above and 1.0 × 10⁴The following. When the weight average molecular weight of the urethane (meth) acrylate is within the above range, the balance between the flexibility and the hardness of the protective layer 2 becomes good, and the occurrence of cracks in the bent portion when the optical layer 10 is molded into a curved surface shape can be suppressed.

The weight average molecular weight of the urethane (meth) acrylate can be measured by GPC (gel permeation chromatography), for example.

Among the above materials, the urethane (meth) acrylate is particularly preferably an alicyclic urethane (meth) acrylate having a carbonate structure. This makes it possible to provide the protective layer 2 with both flexibility (flexibility) and pressure resistance. The protective layer 2 is excellent in weather resistance. Therefore, even when the optical layer 10 is formed into a curved shape, the optical layer 10 can be formed into a layer having excellent water resistance and hot water resistance and excellent weather resistance. The alicyclic urethane (meth) acrylate having a carbonate structure can be obtained by using, as an isocyanate compound, a compound obtained by reacting a polycarbonate diol with an alicyclic diisocyanate, for example.

The content of the urethane (meth) acrylate in the resin composition is not particularly limited, but is preferably 10 wt% or more and 25 wt% or less, and more preferably 12 wt% or more and 24 wt% or less, in the main resin described later. If the content of the urethane (meth) acrylate in the resin composition is less than the lower limit, the protective layer 2 may lack flexibility depending on the type of the urethane (meth) acrylate, and as a result, the water resistance and hot water resistance may be reduced. When the content of the urethane (meth) acrylate in the resin composition exceeds the upper limit, the content of the material other than the urethane (meth) acrylate in the resin composition is relatively decreased, and the scratch resistance of the optical layer 10 may be decreased.

The polyfunctional (meth) acrylate is a (meth) acrylate containing two or more (meth) acryloyl groups in one molecule which contribute to the polymerization reaction.

Since the polyfunctional (meth) acrylate has two or more (meth) acryloyl groups, the hardness of the formed protective layer 2 becomes relatively high. Therefore, by containing the polyfunctional (meth) acrylate, the hard and high-strength protective layer 2 can be obtained.

The polyfunctional (meth) acrylate may contain two or more (meth) acryloyl groups contributing to polymerization reaction in one molecule, and represents the whole monomer or oligomer, and the molecular weight and molecular structure thereof are not particularly limited.

Examples of the polyfunctional (meth) acrylate monomer include 1, 4-butanediol diacrylate, ethoxylated cyclohexanedimethanol diacrylate, tricyclodecane dimethanol diacrylate, ethoxylated bisphenol A diacrylate, dipentaerythritol hexaacrylate, pentaerythritol tetraacrylate, ditrimethylolpropane triacrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate, dipentaerythritol triacrylate, ethoxylated trimethylolpropane triacrylate, ethoxylated pentaerythritol triacrylate, and ethoxylated pentaerythritol tetraacrylate.

Examples of the polyfunctional (meth) acrylate oligomer include polyfunctional epoxy (meth) acrylate and polyfunctional polyester (meth) acrylate.

The polyfunctional epoxy (meth) acrylate oligomer can be obtained, for example, by esterification reaction of an oxirane ring of a low molecular weight bisphenol epoxy resin or a novolak epoxy resin with (meth) acrylic acid.

The polyfunctional polyester (meth) acrylate oligomer can be obtained, for example, by esterifying the hydroxyl group of a polyester oligomer having hydroxyl groups at both ends, which is obtained by condensation of a polyvalent carboxylic acid and a polyvalent alcohol, with (meth) acrylic acid. The polyfunctional polyester (meth) acrylate oligomer can be obtained by esterifying a hydroxyl group at the end of an oligomer obtained by adding an alkylene oxide to a polycarboxylic acid with (meth) acrylic acid.

The polyfunctional (meth) acrylate monomer as above is preferably a combination of a tetrafunctional (meth) acrylate having four (meth) acryloyl groups in one molecule and an aromatic difunctional (meth) acrylate having two (meth) acryloyl groups in one molecule and having an aromatic ring. According to such a combination, a three-dimensional cross-linked structure having an aromatic ring can be formed in the formed protective layer 2. Therefore, the chemical resistance of the protective layer 2 against chemicals such as petroleum solvents can be improved, and the scratch resistance of the protective layer 2 can be improved, so that the above requirement a can be satisfied reliably for a long period of time.

In this case, the content of the tetrafunctional (meth) acrylate in the resin composition is not particularly limited, but is preferably 40 wt% or more and 70 wt% or less, more preferably 40 wt% or more and 65 wt% or less, and the content of the aromatic difunctional (meth) acrylate is not particularly limited, but is preferably 6 wt% or more and 15 wt% or less, more preferably 7 wt% or more and 14 wt% or less, in the main resin described below. If the content of the tetrafunctional (meth) acrylate and the aromatic difunctional (meth) acrylate in the resin composition is less than the lower limit, the chemical resistance of the protective layer 2 may be poor depending on the types of the tetrafunctional (meth) acrylate and the aromatic difunctional (meth) acrylate. When the content of the tetrafunctional (meth) acrylate and the aromatic difunctional (meth) acrylate in the resin composition exceeds the upper limit, the content of the material other than the tetrafunctional (meth) acrylate and the aromatic difunctional (meth) acrylate in the resin composition is relatively decreased, and there is a possibility that the flexibility of the optical layer 10 is decreased.

Also, when the silicon-modified (meth) acrylate has a hydroxyl group, the resin composition preferably contains isocyanate. In this case, the isocyanate functions as a crosslinking agent for bonding (crosslinking) the silicon-modified (meth) acrylate between molecules. Therefore, when isocyanate functions as a crosslinking agent, a hydroxyl group of the silicon-modified (meth) acrylate reacts with an isocyanate group of the isocyanate to form a crosslinked structure composed of a urethane bond. This can improve the scratch resistance of the protective layer 2.

The isocyanate is not particularly limited, and examples thereof include polyisocyanates having two or more isocyanate groups, and in particular, polyfunctional isocyanates further having three or more isocyanate groups are more preferable. This can further improve the scratch resistance of the protective layer 2.

The content of the isocyanate in the resin composition is not particularly limited, but is preferably 2 to 8 wt%, more preferably 3 to 7 wt% in the main resin described later. If the content of isocyanate in the resin composition is less than the lower limit value, the scratch resistance of the protective layer 2 may be reduced depending on the type of isocyanate. If the content of isocyanate in the resin composition exceeds the upper limit, unreacted isocyanate remains as impurities in the coating film, and therefore, depending on the type of isocyanate, the scratch resistance and durability (adhesion of the coating film) of the coating film may be reduced.

In the present specification, the silicon-modified (meth) acrylic resin, the urethane (meth) acrylate, the polyfunctional (meth) acrylate and the isocyanate in the resin composition are "main resins", and among the main resins, the silicon-modified (meth) acrylic resin, the urethane (meth) acrylate and the polyfunctional (meth) acrylate are essential components, and the isocyanate is preferably contained.

Also, the resin composition preferably contains an ultraviolet absorber. This can more reliably prevent or suppress deterioration of the protective layer 2 by ultraviolet rays, and can further increase the weather resistance of the optical layer 10. The ultraviolet absorber is not particularly limited, and examples thereof include triazine-based, benzophenone-based, benzotriazole-based, and cyanoacrylate-based compounds, and one of these compounds or a combination of two of these compounds can be used. Among these, triazine-based ultraviolet absorbers are particularly preferably used, and among the triazine-based ultraviolet absorbers, hydroxyphenyl-triazine-based ultraviolet absorbers are more preferred. This can more significantly exhibit the above-described effects.

The content of the ultraviolet absorber in the resin composition is not particularly limited, but is preferably 1.0 wt% or more and 4.0 wt% or less, and more preferably 1.7 wt% or more and 3.5 wt% or less, based on 100 wt% of the main resin. If the content of the ultraviolet absorber in the resin composition is less than the lower limit, the weather resistance of the protective layer 2 may be reduced. Even if the content of the ultraviolet absorber in the resin composition exceeds the upper limit, the weather resistance is not improved more than that, and the transparency of the protective layer 2 and the adhesion of the protective layer 2 to the base material layer 1 may be impaired.

Also, the resin composition may include a photopolymerization initiator. The photopolymerization initiator is not particularly limited, and benzoin or benzoin alkyl ethers such as benzoin methyl ether, benzoin ethyl ether and benzoin isopropyl ether, aromatic ketones such as benzophenone and benzoylbenzoic acid, α -dicarbonyl such as benzil, benzil ketal such as benzil dimethyl ketal and benzil diethyl ketal, benzil ketals such as acetophenone, 1- (4-dodecylphenyl) -2-hydroxy-2-methylpropan-1-one, 1-hydroxycyclohexylphenyl ketone, 2-hydroxy-2-methyl-1-phenyl-1-propane-1-one, 1- (4-isopropylphenyl) -2-hydroxy-2-methyl-propane-1-one, and mixtures thereof, Acetophenone compounds such as 2-methyl-1- [ 4- (methylthio) phenyl ] -2-morpholinyl-1-one, anthraquinone compounds such as 2-methylanthraquinone, 2-ethylanthraquinone and 2-tert-butylanthraquinone, thioxanthone compounds such as 2, 4-dimethylthioxanthone, 2-isopropylthioxanthone and 2, 4-diisopropylthioxanthone, phosphine oxide compounds such as bis (2,4, 6-trimethylbenzoyl) -phenylphosphine oxide, alpha-acyloxime compounds such as 1-phenyl-1, 2-propanedione-2- (o-ethoxycarbonyl) oxime, ethyl p-dimethylaminobenzoate and isoamyl p-dimethylaminobenzoate, among which amines such as 1- (4-dodecylphenyl) -2-hydroxy-2-methylpropan-1-one, 2-methylanthraquinone, 2, Acetophenones such as 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenyl-1-propan-1-one, 1- (4-isopropylphenyl) -2-hydroxy-2-methyl-propan-1-one, and 2-methyl-1- [ 4- (methylthio) phenyl ] -2-morpholino-1-propanone.

The content of the photopolymerization initiator in the resin composition is not particularly limited, but is preferably 0.5 wt% or more and 10 wt% or less, and more preferably 2.0 wt% or more and 6.0 wt% or less, based on 100 wt% of the main resin. If the content of the photopolymerization initiator in the resin composition is less than the lower limit, it may be difficult to sufficiently cure the resin composition, and even if the content of the photopolymerization initiator in the resin composition exceeds the upper limit, no improvement more than that is observed.

Other materials than the above materials may be contained in the resin composition.

Examples of the other materials include resin materials other than the silicon-modified (meth) acrylic resin, colorants, sensitizers, stabilizers, surfactants, antioxidants, reduction inhibitors, antistatic agents, surface conditioners, and solvents.

The solvent is a component contained in the resin composition in order to reliably make the resin composition varnish, and examples of the solvent include aliphatic hydrocarbons such as hexane, heptane, and cyclohexane, aromatic hydrocarbons such as toluene and xylene, alcohols such as methanol, ethanol, propanol, and butanol, ketones such as methyl ethyl ketone, 2-pentanone, isophorone, and diisobutyl ketone, esters such as ethyl acetate, butyl acetate, isobutyl acetate, and methoxypropyl acetate, cellosolve-based solvents such as ethyl cellosolve, and glycol-based solvents such as methoxypropanol, ethoxypropanol, and methoxybutanol. These can be used alone or in combination. Among these, solvents containing a butyl group such as diisobutyl ketone and isobutyl acetate are preferable. The butyl group-containing solvent has excellent affinity for the polycarbonate-based resin. Therefore, when the base layer 1 contains a polycarbonate-based resin as a base resin, the protective layer 2 formed on the base layer 1 using the resin composition can be formed into a layer having excellent adhesion to the base layer 1.

The thickness of the protective layer 2 is not particularly limited, but is preferably 1 μm or more and 40 μm or less, and more preferably 3 μm or more and 20 μm or less. If the thickness of the protective layer 2 is less than the lower limit, the weather resistance of the optical layer 10 may be reduced. On the other hand, if the thickness of the protective layer 2 exceeds the upper limit, cracks may occur in the bent portion when the optical layer 10 is molded into a curved shape.

In the element a, the adhesion of the second layer cut in a lattice shape to the base material may be 95% or more, but is preferably 98% or more, and more preferably 100%. Thus, even if exposed to chemicals such as petroleum solvents, the peeling of the protective layer 2 from the base layer 1 in the optical layer 10 (cover member) is more reliably suppressed or prevented. Therefore, the appearance of the optical layer 10 can be maintained in a more excellent state.

In the above-mentioned element a, the base material to be prepared may be a base material made of a bisphenol polycarbonate resin as long as the base material contains the bisphenol polycarbonate resin as a main material, but is preferably a base material containing the bisphenol polycarbonate resin as a main material, a visible light absorber, and an ultraviolet light absorber (fourth light absorber). When the visible light absorber and the ultraviolet absorber are contained, the total content of the visible light absorber and the ultraviolet absorber in the base material is preferably 0.30 wt% or more and 0.4 wt% or less, and more preferably about 0.38 wt%. In addition, as the visible light absorber, a combination of the first to third light absorbers is preferable. In the bisphenol type polycarbonate resin, bisphenol a is preferred as the bisphenol. When such a material is used as the base material, it can be said that the peelability of the protective layer 2 to the base material layer 1 is more reliably evaluated by satisfying the requirement a. Therefore, if the requirement a is satisfied in this base material, it can be said that even if the base material is exposed to a chemical such as a petroleum solvent, the peeling of the protective layer 2 from the base material layer 1 in the optical layer 10 (cover member) is more reliably suppressed or prevented.

In the above-mentioned requirement a, the mixed solvent to be prepared may contain 45 wt% or more of the petroleum solvent, but preferably contains 45 wt% or more and 70 wt% or less of the petroleum solvent, and more preferably contains 50 wt% or more and 60 wt% or less of the petroleum solvent. In addition, the petroleum-based solvent is defined in JIS K2201-1991, and may be any of No. 1 (gasoline), No. 2 (rubber volatile oil), No. 3 (soybean volatile oil), No. 4 (mineral spirits), and No. 5 (cleaning solvent). Examples of the components other than the petroleum solvent contained in the mixed solvent include mineral oil (petroleum oil), lubricant additives, rust preventive additives, and surfactants. When such a component is used as the mixed solvent, it can be said that the peelability of the protective layer 2 to the base material layer 1 is more reliably evaluated by satisfying the requirement a. Therefore, when the mixed solvent is used, it can be said that even if the mixed solvent is exposed to chemicals such as petroleum solvents, the peeling of the protective layer 2 from the base layer 1 in the optical layer 10 (cover member) can be more reliably suppressed or prevented as long as the requirement a is satisfied.

In the present invention, it is preferable that the requirement a is satisfied even when an acid solution (chemical) containing 15 wt% or more and 30 wt% or less of nitrileacetic acid (nitrileacetic acid) and a salt thereof in total is used instead of a mixed solvent containing 45 wt% or more of a petroleum-based solvent. This makes it possible to more reliably prevent or suppress the peeling of the protective layer 2 from the base layer 1 in the optical layer 10 (cover member), not only in chemicals such as petroleum solvents, but also in chemicals such as acid solutions containing nitriloacetic acid. Therefore, the protective layer 2 can be said to be a protective layer for the protective substrate layer 1 having more excellent chemical resistance.

In addition, the acid solution preferably contains 5 wt% to 15 wt% of a nonionic surfactant in addition to the nitriloacetic acid and the salt thereof. When the acid solution further contains such a nonionic surfactant, the protective layer 2 can be said to be a protective layer of the protective substrate layer 1 having particularly excellent chemical resistance by satisfying the requirement a for using the acid solution.

When the optical layer 10 is applied to a cover member of a brake lamp or a hazard lamp provided in a moving object such as an automobile or a two-wheeled vehicle, an acid solution containing nitriloacetic acid or a salt thereof is contained in a cleaning liquid or the like used in the cleaning of the moving object. Therefore, it is considered that the protective layer 2 is peeled from the base material layer 1 due to the contact of the acid solution (cleaning solution) with the optical layer 10 (cover member) at the time of car washing.

In the above-mentioned requirement a, the second layer formed on the substrate is preferably subjected to a boiling test by immersing the substrate in boiling hot water for 10 hours before forming the coating film of the mixed solvent. Even in the second layer subjected to such a boiling test, the protective layer 2 can be said to be a protective layer for the protective substrate layer 1 having more excellent chemical resistance, since the above requirement a is satisfied.

In the above-mentioned element A, the second layer formed on the substrate is preferably subjected to Iceper UV Tester (IWASAKI ELECTRIC CO., LTD., manufactured by LTD.) with an ultraviolet illuminance of 150mW/cm before the formation of the coating film of the mixed solvent²Temperature 63 ℃/humidity 50% RH, spray frequency 18 minutes out of 120 minutes, exposure time 72 hours). Even in the second layer subjected to such a weather resistance test, the protective layer 2 satisfies the above requirement a, and therefore can be said to be a protective layer of the protective substrate layer 1 having more excellent chemical resistance.

In addition to the above requirement a, the second layer formed on the substrate preferably satisfies the following requirement B.

A key element B: the second layer having an average thickness of 12 [ mu ] m is provided on a substrate having an average thickness of 2mm and made of a bisphenol type polycarbonate resin to form a laminate composed of the substrate and the second layer, the laminate is allowed to stand under conditions of 85 ℃ for 24 hours in a state where a coating film of the mixed solvent is formed on the second layer, and then is returned to an atmosphere of 25 ℃, and after the mixed solvent is removed, the transmittance (%) of the laminate at a wavelength of 900nm is measured, and the transmittance is 60% or more.

The transmittance may be 60% or more, but is preferably 75% or more, and more preferably 85% or more. When the optical layer 10 having the second layer satisfying the relationship as the protective layer 2 is applied to, for example, a cover member included in a brake lamp and a hazard lamp provided in a moving body such as an automobile or a two-wheeled vehicle, it can be said that even if the cover member is exposed to a chemical such as a petroleum solvent included in a lubricant or a rust preventive agent used for maintenance of the moving body, it is possible to reliably suppress or prevent a decrease in light transmission characteristics (infrared ray transmission characteristics) in infrared rays in various wavelength regions in the optical layer 10 (cover member) due to the protective layer 2 (second layer). Therefore, by applying the optical layer 10 satisfying the requirement B to the cover member, the infrared ray transmission characteristics (light transmission characteristics) of the cover member can be maintained in an excellent state.

In the above-mentioned requirement B, the boiling test and the weather resistance test of the prepared base material, mixed solvent, acid solution, and base material are preferably the same components and test methods as those described in the above-mentioned requirement a. When such a composition and test method are used, the protective layer 2 satisfying the requirement B can be said to be a protective layer of the protective base layer 1 which more reliably suppresses or prevents the deterioration of the infrared transmission characteristics.

< second embodiment >

Next, a second embodiment of the optical layer of the present invention will be described.

Fig. 2 is a longitudinal sectional view showing a second embodiment of the optical layer of the present invention.

Hereinafter, the optical layer 10A of the second embodiment will be mainly described about differences from the optical layer 10 of the first embodiment, and the description about the same matters will be omitted.

The optical layer 10A of the present embodiment is the same as the first embodiment except that the structure of the base material layer is different.

In the present embodiment, the optical layer 10A is a laminate (see fig. 2) including a visible light absorption layer 3 that absorbs visible light, an ultraviolet absorption layer 4 that absorbs ultraviolet light, and a protective layer 2, which are laminated in this order from the lower side. That is, in the present embodiment, the base layer 1 (first layer) in the first embodiment is composed of a laminate of the visible light absorption layer 3 and the ultraviolet absorption layer 4.

In such a laminate, the visible light absorption layer 3 includes a resin material having light transmittance as a main material and a visible light absorber dispersed in the resin material and absorbing visible light, thereby suppressing or preventing transmission of visible light in a specific wavelength region and having a function of allowing transmission of light having a desired wavelength region, and the ultraviolet light absorption layer 4 includes a resin material having light transmittance as a main material and an ultraviolet light absorber dispersed in the resin material and absorbing ultraviolet light, thereby having a function of allowing transmission of infrared light and visible light and suppressing or preventing transmission of ultraviolet light.

The resin material included in the visible light absorption layer 3 and the ultraviolet absorption layer 4 is a material that is included as a main material of each layer and is used to form each layer into a substrate shape, and the same material as the resin material included in the base layer 1 in the first embodiment can be used.

In the present embodiment, the visible light absorber included in the visible light absorbing layer 3 preferably includes at least one of a first light absorber that absorbs light having a wavelength of 300nm or more and 550nm or less, a second light absorber that absorbs light having a wavelength of 450nm or more and 800nm or less, and a third light absorber that absorbs light having a wavelength of 400nm or more and 800nm or less, as in the visible light absorber included in the base layer 1 of the first embodiment. As the first to third light absorbers, the same materials as those described as the first to third light absorbers included in the base layer 1 in the first embodiment can be used.

In the present embodiment, the ultraviolet absorber included in the ultraviolet absorbing layer 4 preferably includes a fourth light absorber that absorbs light having a wavelength of 100nm or more and 400nm or less, as in the case of the ultraviolet absorber that may be included in the base layer 1 of the first embodiment. As this fourth light absorber, the same material as that described as the fourth light absorber that can be included in the base layer 1 in the first embodiment can be used.

In this embodiment, as described above, the base layer (first layer) is composed of a laminate of the visible light absorption layer 3 and the ultraviolet absorption layer 4. Even if the substrate layer (first layer) is formed of such a laminate, if the protective layer 2 (second layer) formed on the laminate (substrate layer) satisfies the requirement a, even if the optical layer 10A applied as the cover member is exposed to chemicals such as petroleum solvents, peeling of the protective layer 2 (second layer) from the substrate layer (first layer) in the optical layer 10A (cover member) can be reliably suppressed or prevented.

The resin composition, the optical layer, the cover member, and the moving object of the present invention have been described above, but the present invention is not limited thereto.

For example, the optical layer of the present invention can be applied to a cover member provided in a brake lamp and a hazard lamp of a mobile body such as an automobile or a two-wheeled vehicle as described above, and can also be applied to a cover member provided in an infrared radar of a mobile body, a windshield and a spoiler of a mobile body, a cover member provided in a weighing machine of a gas station, a lens member (cover member) provided in a monitoring camera, and the like.

When the optical layer of the present invention is applied to a cover member provided in an infrared radar, the infrared radar may be incorporated as a human body sensor provided in, for example, an outdoor ticket vending machine or a vending machine, in addition to the case where the infrared radar is incorporated in a moving body such as an automobile, as described above.

The moving object (moving object of the present invention) having the optical layer of the present invention as a cover member may be a ship, a railway vehicle, an airplane, a bus, a forklift, a working vehicle performing a predetermined work at a construction site or the like, a two-wheeled cart accommodating a golf club, an automated guided vehicle, or the like, in addition to an automobile and a two-wheeled vehicle (motorcycle, bicycle).