JP2022077664A - Optical sheet and optical component - Google Patents

Abstract

To provide an optical sheet and an optical component that can reliably emphasize light in a wavelength region of 620 nm or longer and 750 nm or shorter for a user and allows the user to identify color.SOLUTION: An optical sheet has a first peak having a transmission peak wavelength P1 of transmittance in a wavelength region of 480 nm or longer and 530 nm or shorter and a second peak having an absorption peak wavelength P2 of transmittance in a wavelength region of 550 nm or longer and 610 nm or shorter in a light absorption spectrum, average transmittance in a wavelength region of 630 nm or longer and 780 nm or shorter is 70% or less, and transmittance gradually increases toward a long-wavelength side in a wavelength region A of 630 nm or longer and 700 nm or shorter, transmittance gradually increases toward a long-wavelength side in a wavelength region B of 700 nm or longer and 780 nm or shorter, and TA<TB is satisfied when an average gradual increase rate of transmittance in the wavelength region A is set to TA and an average gradual increase rate of transmittance in the wavelength region B is set to TB.SELECTED DRAWING: Figure 5

Description

The present invention relates to optical sheets and optical components.

For example, an optical sheet that absorbs a specific wavelength range from incident light is known for the purpose of increasing the contrast of the visual field, preventing glare, and the like (see, for example, Patent Document 1). This optical sheet is used by being attached to eyeglasses, sunglasses, sun visors, and the like.

The optical sheet described in Patent Document 1 contains, for example, a resin material and a dye (light absorber) contained in the resin material and absorbing light having a specific wavelength in the light in the visible light region. For example, as a result, the light transmitted through the optical sheet is emphasized in a wavelength range other than the light absorbed by the dye, and the contrast of the visual field can be enhanced.

However, if the optical sheet simply contains a light absorber that absorbs light in a wavelength range other than the wavelength range to be emphasized, it becomes difficult to distinguish colors or it has the effect of emphasizing light of a specific wavelength. It may not be possible to obtain enough. In the past, this point has not been sufficiently examined.

WO2014 / 115705

An object of the present invention is to provide an optical sheet and an optical component capable of reliably emphasizing light in a wavelength range of 620 nm or more and 750 nm or less to a user and allowing the user to distinguish colors. It is in.

Such an object is achieved by the present invention of the following (1) to (10).
(1) A light absorbing layer composed of a resin and a material containing at least one kind of first light absorber and absorbing light in a specific wavelength range in the visible light region, and at least one kind of second light absorber. An optical sheet comprising, and having a polarizing layer having a polarizing function.
In the light absorption spectrum of the optical sheet,
It has a first peak having a transmittance transmission peak wavelength P1 in a wavelength range of 480 nm or more and 530 nm or less, and a second peak having a transmittance absorption peak wavelength P2 in a wavelength range of 550 nm or more and 610 nm or less.
The average transmittance in the wavelength range of 630 nm or more and 780 nm or less is 70% or less, and in the wavelength range A of 630 nm or more and 700 nm or less, the transmittance gradually increases toward the long wavelength side, and the transmittance is gradually increased toward the long wavelength side, and the wavelength range B of 700 nm or more and 780 nm or less. In, the transmittance gradually increases toward the long wavelength side,
An optical sheet characterized in that TA <TB is satisfied when the average gradual increase rate of the transmittance in the wavelength region A is TA and the average gradual increase rate of the transmittance in the wavelength region B is TB.

(2) The TA is 0.14 or more and less than 0.30.
The optical sheet according to (1) above, wherein the TB is 0.40 or more and less than 0.75.

(3) The optical sheet according to (1) or (2) above, wherein the transmittance at the transmission peak wavelength P1 is 8% or more and 40% or less.

(4) The optical sheet according to any one of (1) to (3) above, wherein the transmittance at the absorption peak wavelength P2 is 1% or more and 20% or less.

(5) The optical sheet according to (4) above, wherein the first light absorber is at least one of a quinoline dye, an anthraquinone dye, perylene dye, polymethine dye, porphyrin complex dye, and phthalocyanine dye. ..

(6) The second light absorber is at least one of an azo dye, a stilbene dye, a thiazole dye, a dioxazine dye, a phthalocyanine dye, a disazo dye, a trisazo dye, and a metal complex salt azo dye. The optical sheet according to (4) above.

(7) The optical sheet according to any one of (1) to (6) above, wherein the half width at the first peak is 10 nm or more and 40 nm or less.

(8) The optical sheet according to any one of (1) to (7) above, wherein the full width at half maximum at the second peak is 10 nm or more and 30 nm or less.

(9) The optical sheet according to any one of (1) to (8) above, which has a third peak having a transmittance peak wavelength P3 in a wavelength range of 400 nm or more and 450 nm or less in the light absorption spectrum of the optical sheet. ..

(10) Substrate and
An optical component laminated on the substrate and comprising the optical sheet according to any one of (1) to (9) above.

According to the present invention, it is possible to provide an optical sheet capable of reliably emphasizing light in a wavelength range of 620 nm or more and 750 nm or less to a user and allowing the user to discriminate colors.

It is a perspective view of the sunglasses provided with the optical sheet (1st Embodiment) of this invention. It is a perspective view of the sun visor provided with the optical sheet (1st Embodiment) of this invention. It is a side view schematically showing the optical sheet manufacturing apparatus which manufactures the optical sheet shown in FIG. 1. It is sectional drawing which shows schematically the optical component manufacturing apparatus which manufactures the optical component shown in FIG. 1. It is sectional drawing of the optical component shown in FIG. It is a graph which shows the optical spectrum of the light absorption layer (the specific wavelength absorption layer) included in the optical sheet shown in FIG.

Hereinafter, the optical sheet and the optical component of the present invention will be described in detail based on the preferred embodiments shown in the accompanying drawings.

<First Embodiment>
FIG. 1 is a perspective view of sunglasses provided with the optical sheet (first embodiment) of the present invention. FIG. 2 is a perspective view of a sun visor provided with the optical sheet (first embodiment) of the present invention. FIG. 5 is a cross-sectional view of the optical component shown in FIG. FIG. 6 is a graph showing an optical spectrum of a light absorption layer (specific wavelength absorption layer) included in the optical sheet shown in FIG. 1.

In FIGS. 1, 2, and 5, the upper side is referred to as "upper" or "upper", and the lower side is also referred to as "lower" or "lower". Further, in the drawings referred to in the present specification, the dimensions in the thickness direction are exaggerated and shown, which are significantly different from the actual dimensions.

The optical sheet 1 of the present invention shown in FIGS. 1, 2 and 5 is composed of a material containing a resin and at least one first light absorber, and absorbs light in a specific wavelength range in the visible light region. A specific wavelength absorbing layer 11 (light absorbing layer) and a polarizing layer 12 containing at least one second light absorbing agent and having a polarizing function are provided. Then, in the light absorption spectrum of the optical sheet 1, the first peak having a transmittance transmission peak wavelength P1 in the wavelength range of 480 nm or more and 530 nm or less, and the transmittance absorption peak wavelength P2 in the wavelength range of 550 nm or more and 610 nm or less. It has a second peak. The average transmittance in the wavelength range of 630 nm or more and 780 nm or less is 70% or less, and in the wavelength range A of 630 nm or more and 700 nm or less, the transmittance gradually increases toward the long wavelength side, and the wavelength of 700 nm or more and 780 nm or less. In the region B, the transmittance gradually increases toward the long wavelength side, and when the average gradual increase rate of the transmittance in the wavelength region A is TA and the average gradual increase rate of the transmittance in the wavelength region B is TB, TA < Satisfy TB. As a result, the transmittance of the color in the wavelength region A, that is, yellowish or orangeish red, can be sufficiently suppressed, while the transmittance of the color in the wavelength region B, that is, close to pure red can be gradually increased. As a result, the red color can be effectively emphasized. According to the present invention, since the red color can be clearly emphasized, the visibility of the signal can be enhanced and the autumn leaves can be enjoyed.

When TA ≧ TB, yellow and orange-red colors are conspicuous, and the red color cannot be clearly emphasized. Further, when the average transmittance in the wavelength range of 630 nm or more and 780 nm or less exceeds 70%, yellow and orange colors become conspicuous, and the effect of TA <TB cannot be sufficiently obtained.

Such an optical sheet 1 is used for sunglasses (optical component 10) shown in FIG. 1 and a sun visor (optical component 10') shown in FIG.

As shown in FIG. 1, the sunglasses (optical component 10) include a frame 2 mounted on the user's head and a lens 3 (optical component) with an optical sheet fixed to the frame 2. In the present specification, the "lens" includes both a lens having a light-collecting function and a lens having no light-collecting function.

As shown in FIG. 1, the frame 2 is attached to the user's head, and has a rim portion 21, a bridge portion 22, a temple portion 23 hung on the user's ear, and a nose pad portion 24. have. Each rim portion 21 has a ring shape, and is a portion on which the lens 3 with an optical sheet is mounted.

The bridge portion 22 is a portion that connects the rim portions 21. The temple portion 23 has a vine shape and is connected to the edge portion of each rim portion 21. The temple portion 23 is a portion that can be hung on the user's ear. The nose pad portion 24 is a portion that comes into contact with the user's nose when the sunglasses (optical component 10) are worn on the user's head. As a result, the mounted state can be stably maintained.

The shape of the frame 2 is not limited to the one shown in the figure as long as it can be attached to the user's head.

The optical component of the present invention has a lens 4 (base material) and an optical sheet 1 laminated on the front surface side (the side opposite to the human eye in the mounted state) of the lens 4. As a result, it is possible to exert the function as sunglasses while enjoying the advantages of the optical sheet 1 described above.

As shown in FIG. 2, the sun visor (optical component 10') has a ring-shaped mounting portion 5 mounted on the user's head and a brim 6 provided in front of the mounting portion 5. There is. The brim 6 has a light transmitting member 7 (base material) and an optical sheet 1 provided on the upper surface of the light transmitting member 7. As a result, the function as a sun visor can be exhibited while enjoying the advantages of the optical sheet 1 described above.

The constituent materials of the lens 4 and the light transmissive member 7 are not particularly limited as long as they have light transmissibility, and various resin materials, various glasses, and the like can be mentioned, but they are of the same type as the polycarbonate of the optical sheet 1. Polycarbonate is preferred. As a result, the adhesion between the lens 4 or the light transmissive member 7 and the optical sheet 1 can be improved.

Hereinafter, the optical sheet 1 will be described in detail. In the following, a case of laminating on the lens 4 (base material) will be typically described.

As shown in FIG. 5, the optical sheet 1 has a specific wavelength absorption layer 11, a polarizing layer 12, a protective layer 13, an adhesive layer 14, and an adhesive layer 15. In the optical sheet 1, the specific wavelength absorption layer 11, the adhesive layer 14, the polarizing layer 12, the adhesive layer 15, and the protective layer 13 are laminated in this order. Further, the optical sheet 1 is joined to the lens 4 in the direction in which the specific wavelength absorption layer 11 is located on the lens 4 side.

The specific wavelength absorption layer 11 contains polycarbonate as a main material, a light absorber (first light absorber), and an ultraviolet absorber.

<Resin>
The resin is not particularly limited, and examples thereof include polycarbonate, polyamide, polyvinyl chloride, polyethylene, polypropylene and the like, and among these, polycarbonate is preferable.

The polycarbonate is not particularly limited, and various types can be used, but among them, aromatic polycarbonate is preferable. The aromatic polycarbonate has an aromatic ring in its main chain, whereby the strength of the optical sheet 1 can be further improved.

This aromatic polycarbonate is synthesized, for example, by an interfacial polycondensation reaction between bisphenol and phosgene, a transesterification reaction between bisphenol and diphenyl carbonate, and the like.

Examples of the bisphenol include bisphenol A and bisphenol (modified bisphenol) which is the origin of the repeating unit of polycarbonate represented by the following formula (1).

（式（１）中、Ｘは、炭素数１～１８のアルキル基、芳香族基または環状脂肪族基であり、ＲａおよびＲｂは、それぞれ独立して、炭素数１～１２のアルキル基であり、ｍおよびｎは、それぞれ０～４の整数であり、ｐは、繰り返し単位の数である。）

(In the formula (1), X is an alkyl group having 1 to 18 carbon atoms, an aromatic group or a cyclic aliphatic group, and Ra and Rb are independently alkyl groups having 1 to 12 carbon atoms. , M and n are integers from 0 to 4, respectively, and p is the number of repeating units.)

Specific examples of the bisphenol that is the origin of the repeating unit of the polycarbonate represented by the formula (1) include 4,4'-(pentane-2,2-diyl) diphenol and 4,4'-(. Pentan-3,3-diyl) diphenol, 4,4'-(butane-2,2-diyl) diphenol, 1,1'- (cyclohexanediyl) diphenol, 2-cyclohexyl-1,4-bis ( 4-Hydroxyphenyl) benzene, 2,3-biscyclohexyl-1,4-bis (4-hydroxyphenyl) benzene, 1,1'-bis (4-hydroxy-3-methylphenyl) cyclohexane, 2,2'- Examples thereof include bis (4-hydroxy-3-methylphenyl) propane, and one or more of these can be used in combination.

In particular, as the polycarbonate, it is preferable to use bisphenol-type polycarbonate having a skeleton derived from bisphenol as a main component. By using such a bisphenol type polycarbonate, the optical sheet 1 exhibits further excellent strength.

The average molecular weight of such polycarbonate is preferably 20,000 or more and 30,000 or less, more preferably 23,000 or more and 28,000 or less, and further preferably 24,000 or more and 27,500 or less.

Thereby, the strength of the optical sheet 1 can be sufficiently increased. In addition, the fluidity can be sufficiently increased in the molten state of the polycarbonate. Thereby, for example, when the optical sheet 1 is manufactured by extrusion molding, the extrusion molding can be performed in a state where the molten polycarbonate and the light absorber are sufficiently mixed. Therefore, it is possible to prevent the light absorber from being excessively aggregated after molding. Further, since the viscosity average molecular weight Mv of the polycarbonate is 20,000 or more and 30,000 or less, it has sufficient strength. From the above, the optical sheet 1 of the present invention prevents the light absorber from aggregating and has sufficient strength.

Further, the polycarbonate has a melt flow rate (MFR) measured according to JIS K7210 preferably 3 g / 10 min or more and 30 g / 10 min or less, and more preferably 15 g / 10 min or more and 25 g / 10 min or less. .. This makes it possible to sufficiently increase the fluidity of the polycarbonate in the molten state. Therefore, for example, when the optical sheet 1 is manufactured by extrusion molding, the extrusion molding can be performed in a state where the molten polycarbonate and the light absorber are sufficiently mixed.

Further, the polycarbonate preferably has a water absorption rate of 0.02% or more and 0.2% or less, and more preferably 0.04% or more and 0.15% or less. This makes it possible to perform extrusion molding in a state where the molten polycarbonate and the light absorber are sufficiently mixed. Therefore, it is possible to prevent the light absorber from aggregating excessively.

The water absorption rate in the present specification is a value measured by Aquatrack 3E (manufactured by Brabender).

The content of the polycarbonate in the specific wavelength absorption layer 11 is preferably 87 wt% or more and 99.949 wt% or less, and more preferably 90 wt% or more and 99.87 wt% or less. Thereby, the effect of the present invention can be more reliably exhibited.

<Light absorber (first light absorber)>
The light absorber absorbs light of a specific wavelength. In the present specification, "absorbing light" means that the value of the absorbance at the maximum absorption wavelength in the visible light region of 420 nm to 780 nm is λ1, and the value on the wavelength side 20 nm lower than λ1 is λ2, on the wavelength side 20 nm higher. When the value is λ3, it means that the absorbance λ1 / λ2 or the absorbance λ1 / λ3 is 1.0 or more.

The light absorber (first light absorber) is not particularly limited as long as it absorbs light of a specific wavelength among the light in the wavelength range of 350 nm or more and 780 nm or less, and is not particularly limited. Examples thereof include dyes, perylene dyes, polymethine dyes, porphyrin complex dyes, phthalocyanine dyes and the like, and one or a combination of two or more of these can be used. This makes it possible to easily reproduce the light absorption spectrum as described later.

Examples of the quinoline dye include 2-methylquinoline, 3-methylquinoline, 4-methylquinoline, 6-methylquinoline, 7-methylquinoline, 8-methylquinoline, 6-isopropylquinoline, and 2,4-dimethylquinoline. Alkyl substituted quinoline compounds such as 2,6-dimethylquinoline and 4,6,8-trimethylquinoline, 2-aminoquinoline, 3-aminoquinoline, 5-aminoquinoline, 6-aminoquinoline, 8-aminoquinoline, 6-amino Amino group substituted quinoline compounds such as -2-methylquinoline, alkoxy group substituted quinoline compounds such as 6-methoxy-2-methylquinoline, 6,8-dimethoxy-4-methylquinoline, 6-chloroquinoline, 4,7-dichloro Examples thereof include halogen group substituted quinoline compounds such as quinoline, 3-bromoquinoline and 7-chloro-2-methylquinoline.

By blending such a quinoline-based dye, it is possible to absorb light having a wavelength range of 350 nm or more and 550 nm or less among the light incident on the specific wavelength absorption layer 11. It is preferable to have an absorption peak in a wavelength range of 400 nm or more and 550 nm or less.

Examples of the anthraquinone dye 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-trifluoro Anthraquinone, (10) 2- (m-nitroanilino) -1,3,4-trifluoroanthraquinone, (11) 2- (p-tershall butyl anthraquinone) -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-dichloroanilinone) -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-trichloroanilinone) -1,3,4-trifluoroanthraquinone, (18) 2 -(2,3,5,6-tetrachloroanilinone) -1,3,4-trifluoroanthraquinone, (19) 2- (2,3,5,6-tetrafluoroanilino) -1,3, 4-Trifluoroanthraquinone, (20) 3- (2,3,4,5-tetrafluoroanilinone) -2-butoxy-1,4-difluoroanthraquinone, (21) 3- (4-cyano-3-chloroanilinone) ) -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-sia) Noanilino) -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, (28) 2,3-dianilino-1,4-difluoroanthraquinone, (29) 2,3-bis (p-tershalbutylanilinone) -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-tetrachloroanilinone) -1,4-difluoroanthraquinone, (35) 2,3-bis (2,3,5) 6-Tetrafluoroanilinone) -1,4-difluoroanthraquinone, (36) 2,3-bis (p-cyanoanilino) -1-methoxyethoxy-4-fluoroanthraquinone, (37) 2- (2,6-dichloro Anilino) -1,3,4-trichloroanthraquinone, (38) 2- (2,3,5,6-tetrafluoroanthraquinone) -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-methylanilinone) -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, (53) 1,2,3,4-tetra (p-methoxyphenoxy)- Anthraquinone and the like can be mentioned.

By blending such an anthraquinone-based dye, it is possible to absorb light having a wavelength of 450 nm or more and 600 nm or less among the light incident on the specific wavelength absorption layer 11. It is preferable to have an absorption peak in a wavelength range of 500 nm or more and 600 nm or less.

Examples of the perylene dye include N, N'-dimethylperylene-3,4,9,10-tetracarboxylic acid diimide and N, N'-diethylperylene-3,4,9,10-tetracarboxylic acid diimide. , N, N'-bis (4-methoxyphenyl) -perylene-3,4,9,10-tetracarboxylic acid diimide, N, N'-bis (4-ethoxyphenyl) -perylene-3,4,9, Examples thereof include 10-tetracarboxylic acid diimide, N, N'-bis (4-chlorophenyl) -perylene-3,4,9,10-tetracarboxylic acid diimide, and N, N'-bis are particularly preferable. Examples thereof include (3,5-dimethylphenyl) -perylene-3,4,9,10-tetracarboxylic acid diimide.

By blending such a perylene-based dye, it is possible to absorb light having a wavelength of 400 nm or more and 800 nm or less among the light incident on the specific wavelength absorption layer 11. It is preferable to have an absorption peak in a wavelength range of 600 nm or more and 780 nm or less.

Examples of the polymethine pigment include streptocyanine or open-chain cyanine, hemicyanine, closed cyanine, merocyanine and the like.

By blending such a polymethine dye, it is possible to absorb light having a wavelength of 400 nm or more and 700 nm or less among the light incident on the specific wavelength absorption layer 11. It is preferable to have an absorption peak in a wavelength range of 450 nm or more and 550 nm or less.

Examples of the porphyrin complex dye include tetraazaporphyrin metal complex (tetraazaporphyrin metal complex type dye), tetraarylporphyrin, octaethylporphyrin and the like.

By blending such a porphyrin complex dye, it is possible to absorb light having a wavelength of 500 nm or more and 700 nm or less among the light incident on the specific wavelength absorption layer 11. It is preferable to have an absorption peak in a wavelength range of 550 nm or more and 600 nm or less.

Examples of the phthalocyanine dye include sodium CoPc-4-sulfonic acid salt, cobalt Pc tetracarboxylic acid, octahydroxyNiPc and the like.

By blending such a phthalocyanine dye, it is possible to absorb light having a wavelength of 550 nm or more and 750 nm or less among the light incident on the specific wavelength absorption layer 11. It is preferable to have an absorption peak in a wavelength range of 550 nm or more and 600 nm or less.

By blending the above light absorber, it is possible to absorb light in a specific wavelength range. Therefore, for example, the user can clearly recognize the contour of an object or a person in the worn state, and can enhance safety.

The content of the light absorber (total of each light absorber) in the specific wavelength absorbing layer 11 is preferably 0.001 wt% or more and 5 wt% or less, and more preferably 0.003 wt% or more and 4 wt% or less. preferable. This makes it possible to more reliably exert the above effect. If the content is too small, the effect as a light absorber may not be sufficiently obtained. On the other hand, if the content is too large, the light absorber tends to aggregate easily.

The basis weight of the light absorber (total of each light absorber) in the specific wavelength absorbing layer 11 is preferably 0.05 mg / m ² or more and 500 mg / m ² or less, and 1 mg / m ² or more and 100 mg / m. It is more preferably ² or less. Thereby, the effect of the present invention can be more reliably exhibited.

<UV absorber>
The ultraviolet absorber absorbs ultraviolet rays (light having a wavelength range of 100 nm or more and 420 nm or less). As a result, it is possible to alleviate the irradiation of ultraviolet rays to the eyes of the user, and it is possible to protect the eyes of the user. Further, it is possible to prevent the light absorber from being deteriorated by ultraviolet rays. That is, the ultraviolet absorber functions as a deterioration inhibitor that prevents deterioration of the light absorber.

The ultraviolet absorber is not particularly limited, and examples thereof include a triazine-based compound, a benzophenone-based compound, a benzotriazole-based compound, and a cyanoacrylate-based compound, and one or a combination of two or more of these can be used. Among these, triazine compounds are particularly preferably used. Thereby, deterioration of the specific wavelength absorbing layer 11 (polycarbonate and the light absorber) due to ultraviolet rays can be prevented or suppressed, and the weather resistance of the optical sheet 1 can be improved.

Examples of triazine-based compounds include 2-mono (hydroxyphenyl) -1,3,5-triazine compound, 2,4-bis (hydroxyphenyl) -1,3,5-triazine compound, and 2,4,6-tris (2,4,6-tris). Hydroxylphenyl) -1,3,5-triazine compounds, specifically 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, 2,4-Diphenyl- (2-hydroxy-4-butoxyphenyl) -1,3,5-triazine, 2,4-diphenyl-6- (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-dodecyl) Oxyphenyl) -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-methoxycarbonylpropyloxyphenyl) -1,3,5- Triazine, 2,4,6-tris (2-hydroxy-4-ethoxycarbonylethyloxyphenyl) -1,3,5-triazine, 2,4,6-tris (2-hydroxy-4- (1- (2)) -Ethoxyhexyloxy) -1-oxopropane-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-ethoxyethoxyphenyl) -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-methoxycarbonylpropyloxyphenyl) -1,3,5-triazine, 2,4 6-Tris (2-hydroxy-3-methyl-4-ethoxycarbonylethyloxyphenyl) -1,3,5-triazine, 2,4,6-Tris (2-hydroki) Examples thereof include 3-methyl-4- (1- (2-ethoxyhexyloxy) -1-oxopropane-2-yloxy) phenyl) -1,3,5-triazine. Examples of commercially available triazine-based ultraviolet absorbers include "Tinubin 1577", "Tinubin 460", "Tinubin 477" (manufactured by BASF Japan), and "ADEKA STUB LA-F70" (manufactured by ADEKA).

The specific wavelength absorption layer 11 further contains an ultraviolet absorber that absorbs light in the wavelength range of 100 nm or more and 420 nm or less as described above, so that the wavelength of the light incident on the specific wavelength absorption layer 11 is 100 nm or more and 420 nm or less. Can absorb the light of. Thereby, deterioration of the specific wavelength absorbing layer 11 (polycarbonate and the light absorber) due to ultraviolet rays can be prevented or suppressed, and the weather resistance of the optical sheet 1 can be improved.

The content of the ultraviolet absorber in the specific wavelength absorbing layer 11 is preferably 0.05 wt% or more and 8 wt% or less, and more preferably 0.07 wt% or more and 6 wt% or less. This makes it possible to more reliably exert the above effect. If the content is too small, the effect as an ultraviolet absorber may not be sufficiently obtained. On the other hand, if the content is too large, the ultraviolet absorber tends to aggregate easily.

The basis weight of the ultraviolet absorber in the specific wavelength absorbing layer 11 is preferably 0.01 g / m ² or more and 100 g / m ² or less, and 0.1 g / m ² or more and 10 g / m ² or less. More preferred. This makes it possible to more reliably exert the above effect.

The thickness of the specific wavelength absorption layer 11 is not particularly limited, but is preferably 0.05 mm or more and 1.5 mm or less, and more preferably 0.3 mm or more and 0.7 mm or less. As a result, the handleability can be improved, and it is possible to prevent the optical component as a whole from being unnecessarily thickened.

Further, the specific wavelength absorption layer 11 may be manufactured by stretching or may be manufactured without stretching, but the degree of stretching is preferably 10% or less. It is more preferably 5% or less. This makes it possible to prevent or suppress color unevenness, light absorber unevenness, and ultraviolet absorber unevenness during stretching.

Further, when the melting point of the polycarbonate is t1 and the melting point of the light absorber is t2, it is preferable that t1 <t2 is satisfied. This makes it possible to prevent the light absorber from being altered or discolored by heat when the molten polycarbonate and the light absorber are mixed.

Further, when the melting point of the polycarbonate is t1 and the melting point of the ultraviolet absorber is t3, it is preferable that t1 <t3 is satisfied. This makes it possible to prevent the ultraviolet absorber from being altered or discolored by heat when the molten polycarbonate and the ultraviolet absorber are mixed.

The melting point t1 of the polycarbonate is preferably 250 ° C. or higher and 400 ° C. or lower, and more preferably 270 ° C. or higher and 350 ° C. or lower.

The melting point t2 of the light absorber is preferably 300 ° C. or higher and 400 ° C. or lower, and more preferably 330 ° C. or higher and 360 ° C. or lower. Further, the melting point t3 of the ultraviolet absorber is preferably 310 ° C. or higher and 370 ° C. or lower, and more preferably 340 ° C. or higher and 360 ° C. or lower. By setting the melting points t1 to t3 in the above numerical range, the above effect can be more reliably exhibited.

The specific wavelength absorption layer 11 may contain a dye different from the dyes mentioned above. The dye 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, but for example, phthalocyanine pigments such as phthalocyanine green and phthalocyanine blue, fast yellow, disazo yellow, condensed azo yellow, penzoimidazolone yellow, dinitroaniline orange, penzoimidazolone orange and toluidin red. , Permanent Carmine, Permanent Red, Naftor Red, Condensed Azored, Benzimidazolone Carmine, Benzimidazolone Brown, etc. , Kinophthalone pigments such as quinophthalone yellow, isoindolin pigments such as isoindolin yellow, nitroso pigments such as nickeldioxime yellow, perinone pigments such as perinone orange, quinacridone magenta, quinacridon maroon, quinacridone scarlet, quinacridone red, etc. Kinacridone pigments, perylene pigments such as perylene red and perylene maroon, pyrrolopyrrole pigments such as diketopyrrolopyrrole red, organic pigments such as dioxazine pigments such as dioxazine violet, carbon black, lamp black, furnace black , Carbon pigments such as ivory black, graphite and fullerene, chromate pigments such as yellow lead and molybdate orange, cadmium yellow, cadmium lithopon yellow, cadmium orange, cadmium lithopon orange, silver vermilion, cadmium red, cadmium litho Ponred, sulfide pigments such as sulfide, ocher, titanium yellow, titanium barium nickel yellow, red iron oxide, lead tan, amber, brown iron oxide, zinc iron chrome brown, chrome oxide, cobalt green, cobalt chrome green, titanium cobalt green , Cobalt blue, Cerulean blue, Cobalt aluminum chrome blue, Iron black, Manganese ferrite black, Cobalt ferrite black, Copper chrome black, Copper chrome Manganese black and other oxide pigments, Viridian and other hydroxide pigments, Navy blue, etc. Examples thereof include ferrocyanide pigments, silicate pigments such as ultramarine, phosphate pigments such as cobalt violet and mineral violet, and inorganic pigments such as cadmium sulfide and cadmium selenium. One of them or two or more of them can be used in combination.

The dye is not particularly limited, and for example, a metal complex dye, a cyanide dye, a xanthene dye, an azo dye, a hibiscus dye, a blackberry dye, a raspberry dye, a pomegranate juice dye, a chlorophyll dye, a tetraazoporphyrin compound and the like. Examples thereof include porphyrin compounds, and one or a combination of two or more of these can be used.

(Polarizing layer)
The polarizing layer 12 contains a light absorber (second light absorber) and has a function of extracting linearly polarized light having a polarizing surface in a predetermined direction from incident light (unpolarized natural light). As a result, the incident light incident on the eyes through the optical sheet 1 is polarized.

The degree of polarization of the polarizing layer 12 is not particularly limited, but is preferably 50% or more and 100% or less, and more preferably 80% or more and 100% or less. The visible light transmittance of the polarizing layer 12 is not particularly limited, but is preferably 10% or more and 80% or less, and more preferably 20% or more and 50% or less.

The constituent material of such a polarizing layer 12 is not particularly limited as long as it has the above-mentioned function, and for example, polyvinyl alcohol (PVA), partially formalized polyvinyl alcohol, polyethylene vinyl alcohol, polyvinyl butyral, polycarbonate, ethylene-. A polymer film composed of a partially ken-valent product of a vinyl acetate copolymer, which is uniaxially stretched by adsorbing and dyeing a bicolor substance such as iodine or a bicolor dye, a dehydrated product of polyvinyl alcohol or poly. Examples thereof include a polyene-based oriented film such as a dehydrochloride-treated product of vinyl chloride.

Among these, the polarizing layer 12 is preferably a polymer film containing polyvinyl alcohol (PVA) as a main material, which is adsorbed and dyed with a light absorber and uniaxially stretched. Polyvinyl alcohol (PVA) is a material having excellent transparency, heat resistance, affinity with a light absorber, and orientation during stretching. Therefore, the polarizing layer 12 using PVA as a main material has excellent heat resistance and an excellent polarizing function.

Examples of the light absorber (second light absorber) include azo dyes, stilbene dyes, thiazole dyes, dioxazine dyes, phthalocyanine dyes, disuazo dyes, trisazo dyes, metal complex salt azo dyes and the like. , At least one or a plurality of these can be used in combination. This makes it possible to easily reproduce the light absorption spectrum as described later.

The polarizing layer 12 may further contain iodine, a dichroic dye, and the like. Examples of the bicolor dye include chloratin fast red, congo red, brilliant blue 6B, benzopurine, chlorazole black BH, direct blue 2B, diamine green, chrysophenone, sirius yellow, direct fast red, acid black and the like. Be done.

The thickness of the polarizing layer 12 is not particularly limited, and is preferably 5 μm or more and 60 μm or less, and more preferably 10 μm or more and 40 μm or less.

(Protective layer)
The protective layer 13 is located on the outermost side when the optical sheet 1 is joined to the lens 4, and has a function of protecting the layer inside the protective layer 13. The thickness of the protective layer 13 is not particularly limited, and is preferably, for example, 10 μm or more and 1000 μm or less, and more preferably 30 μm or more and 60 μm or less.

The constituent material of the protective layer 13 is not particularly limited as long as it has light transmittance, and examples thereof include various resin materials and various glass materials. The resin material is not particularly limited, and examples thereof include the same materials as the resin material of the specific wavelength absorption layer 11 described above, but it is preferable that the resin material is the same as the resin material of the specific wavelength absorption layer 11.

Further, the protective layer 13 is preferably stretched in one direction, and the stretchability is preferably 1% or more and 10% or less, and more preferably 2% or more and 8% or less. Further, it is preferable that the stretching direction coincides with the stretching direction of the polarizing layer 12. As a result, the polarization characteristics of the optical sheet 1 as a whole can be enhanced.

(Adhesive layer)
The adhesive layer 14 has a function of joining the specific wavelength absorption layer 11 and the polarizing layer 12. The adhesive layer 15 has a function of joining the polarizing layer 12 and the protective layer 13.

The adhesive (or adhesive) constituting the adhesive layer 14 and the adhesive layer 15 is not particularly limited, and examples thereof include acrylic adhesives, urethane adhesives, epoxy adhesives, and silicone adhesives. Can be mentioned. Of these, urethane-based adhesives are preferable. As a result, the transparency, adhesive strength, and durability of the adhesive layer 14 and the adhesive layer 15 can be made more excellent, and the followability to the shape change can be made particularly excellent.

Further, the adhesives constituting the adhesive layer 14 and the adhesive layer 15 may be of the same type or may be different.

The thicknesses of the adhesive layer 14 and the adhesive layer 15 are not particularly limited, and are preferably, for example, 5 μm or more and 60 μm or less, and more preferably 10 μm or more and 40 μm or less. The thicknesses of the adhesive layer 14 and the adhesive layer 15 may be the same or different.

By blending the above-mentioned light absorbers (first light absorber and second light absorber) in the optical sheet 1, light in a specific wavelength range can be absorbed, and the user can use the optical sheet 1. In the worn state, the contours of objects and people can be clearly recognized, and safety can be enhanced.

Further, by adjusting the wavelength range of the light absorbed by the light absorber, the light of a predetermined color can be emphasized to the user. In particular, by emphasizing red light (for example, light in the wavelength range of 620 nm or more and 750 nm or less) to the user, the yellow light around 580 nm, which is generally the most dazzling for humans, is cut off, resulting in eye fatigue. In addition to being able to prevent it, the beauty of autumn leaves can be felt more strongly because it emphasizes warm colors such as red, even though it is gray, which is the standard color for sunglasses.

Conventionally, red light is emphasized by simply blending a light absorber that absorbs light in a wavelength range other than red light. However, if there are too many light absorbers that absorb light in a wavelength range other than red light, the transmittance in the wavelength range other than red light may be too low and the red light may be emphasized too much. As a result, it may be difficult to distinguish colors. Further, if the amount of the light absorber that absorbs the light in the wavelength range other than the red light is too small, the effect of emphasizing the red light may not be sufficiently obtained.

Therefore, the present inventors have repeatedly studied diligently and found that the specific wavelength absorption layer 11 having the following configuration is effective in solving the above-mentioned problems, and have completed the present invention. rice field. This will be described below.

FIG. 6 is a graph showing the light absorption spectrum of the specific wavelength absorption layer 11 (light absorption layer) represented by the wavelength [nm] on the horizontal axis and the transmittance [%] on the vertical axis. The transmittance on the vertical axis is assumed to have a correlation with the light absorption rate, and it is assumed that the transmittance is small when the light absorption rate is large, and the transmittance is large when the light absorption rate is small.

As shown in FIG. 6, the light absorption spectrum of the specific wavelength absorption layer 11 is represented by a curve having a first peak Pa, a second peak Pb, and a third peak Pc.

The first peak Pa has a transmission peak wavelength P1 having a transmittance in a wavelength range of 480 nm or more and 530 nm or less. The second peak Pb has an absorption peak wavelength P2 having a transmittance in a wavelength range of 550 nm or more and 610 nm or less. The third peak Pc has a transmission peak wavelength P3 having an absorptivity in a wavelength range of 400 nm or more and 450 nm or less.

By having the first peak Pa, the complementary color of red can be emphasized, and as a result, the red color can be further emphasized.

The transmittance [%] at the transmission peak wavelength P1 is preferably 8% or more and 40% or less, and more preferably 10% or more and 35% or less. As a result, the complementary color of red can be emphasized more, and as a result, red can be emphasized more effectively.

Further, by having the second peak Pb, it is possible to absorb a color close to red, and as a result, the red color can be further emphasized.

The transmittance [%] at the absorption peak wavelength P2 is preferably 1% or more and 20% or less, and more preferably 2% or more and 17% or less. As a result, a color close to red can be absorbed more reliably, and as a result, red can be emphasized more effectively.

Further, by having the third peak Pc having the transmission peak wavelength P3 of the absorption rate in the wavelength range of 400 nm or more and 450 nm or less, it is possible to suppress excessive absorption of blue light, and as a result, red color is further effective. Can be emphasized.

The transmittance [%] at the transmission peak wavelength P3 is preferably 6% or more and 37% or less, and more preferably 9% or more and 30% or less. This makes it possible to more reliably suppress the excessive absorption of blue light, and as a result, the red color can be emphasized more effectively.

Further, the full width at half maximum W1 [nm] in the first peak Pa is preferably 10 nm or more and 40 nm or less, and more preferably 15 nm or more and 35 nm or less. As a result, the complementary color of red can be emphasized more, and as a result, red can be emphasized more effectively.

The full width at half maximum at the first peak Pa is defined as follows. First, the absorbance is measured outward from the transmission peak wavelength P1 in increments of 2 nm on both sides of the transmission peak wavelength P1, and the first wavelength at which the change in absorbance becomes 0.005 or less (more than 30 nm far from the center). ) Are detected, and the wavelength having the higher transmittance is set as the bottom wavelength. Then, the width of the first peak Pa when the value is half the difference between the transmittance of the bottom wavelength and the transmittance of the transmission peak wavelength P1 is defined as the half width at the first peak Pa.

Further, the full width at half maximum W2 [nm] in the second peak Pb is preferably 10 nm or more and 30 nm or less, and more preferably 15 nm or more and 25 nm or less. As a result, a color close to red can be absorbed more reliably, and as a result, red can be emphasized more effectively.

The full width at half maximum at the second peak Pb is defined as follows in the same manner as above. First, the absorbance is measured outward from the absorption peak wavelength P2 in increments of 2 nm on both sides of the absorption peak wavelength P2, and the first wavelength at which the change in absorbance becomes 0.005 or less (10 nm or more far from the center). ) Are detected, and the wavelength having the higher transmittance is set as the bottom wavelength. Then, the width of the second peak Pb when the value is half the difference between the transmittance of the bottom wavelength and the transmittance of the absorption peak wavelength P2 is defined as the half width at the second peak Pb.

The full width at half maximum W3 [nm] at the third peak Pc is preferably 10 nm or more and 40 nm or less, and more preferably 15 nm or more and 35 nm or less. This makes it possible to more reliably suppress the excessive absorption of blue light, and as a result, the red color can be emphasized more effectively.

The full width at half maximum at the third peak Pc is defined as follows in the same manner as above. First, the absorbance is measured outward from the transmission peak wavelength P3 in increments of 2 nm on both sides of the transmission peak wavelength P3, and the first wavelength at which the change in absorbance becomes 0.005 or less (10 nm or more far from the center). ) Are detected, and the wavelength having the higher transmittance is set as the bottom wavelength. Then, the width of the third peak Pc when the value is half the difference between the transmittance of the bottom wavelength and the transmittance of the transmission peak wavelength P3 is defined as the half width at the third peak Pc.

Here, in the present invention, in the wavelength range of 630 nm or more and 780 nm or less, which is a wavelength range of red or a color relatively close to red, the transmittance gradually increases toward the long wavelength side in the wavelength range A of 630 nm or more and 700 nm or less. However, in the wavelength range B of 700 nm or more and 780 nm or less, the transmittance gradually increases toward the long wavelength side. In the present invention, TA <TB is satisfied when the average gradual increase rate of the transmittance in the wavelength region A is TA and the average gradual increase rate of the transmittance in the wavelength region B is TB. As a result, the transmittance in the wavelength range B of 700 nm or more and 780 nm or less, that is, closer to pure red, is gradually increased rather than the color in the wavelength range A of 630 nm or more and 700 nm or less, that is, yellow or orange-red. be able to. That is, while suppressing the transmittance of yellow and orange-red, the transmittance can be gradually increased as the color approaches pure red. As a result, the red color can be effectively emphasized.

Further, by setting the average transmittance in the wavelength range of 630 nm or more and 780 nm or less to 70% or less, the above relationship can be more reliably emphasized.

The average gradual increase rate is a value obtained by measuring the transmittance on the high wavelength side in increments of 2 nm and calculating the average of the increase rates of each transmittance.

When TA ≧ TB, yellow and orange-red colors are conspicuous, and the red color cannot be clearly emphasized. Further, when the average transmittance in the wavelength range of 630 nm or more and 780 nm or less exceeds 70%, yellow and orange colors become conspicuous, and the effect of TA <TB cannot be sufficiently obtained.

As described above, the optical sheet 1 of the present invention is composed of a material containing a resin and at least one first light absorber, and is a specific wavelength absorption layer 11 that absorbs light in a specific wavelength range in the visible light region. (Light absorption layer) and a polarizing layer 12 containing at least one second light absorber and having a polarizing function. Then, in the light absorption spectrum of the optical sheet 1, the first peak having a transmittance transmission peak wavelength P1 in the wavelength range of 480 nm or more and 530 nm or less, and the transmittance absorption peak wavelength P2 in the wavelength range of 550 nm or more and 610 nm or less. It has a second peak. The average transmittance in the wavelength range of 630 nm or more and 780 nm or less is 70% or less, and in the wavelength range A of 630 nm or more and 700 nm or less, the transmittance gradually increases toward the long wavelength side, and the wavelength of 700 nm or more and 780 nm or less. In region B, the transmittance gradually increases toward the long wavelength side, and when the average gradual increase rate of the transmittance in the wavelength region A is TA and the average gradual increase rate of the transmittance in the wavelength region B is TB, TA <TB. To be satisfied. As a result, the transmittance of the color in the wavelength region A, that is, yellowish or orangeish red, can be sufficiently suppressed, while the transmittance of the color in the wavelength region B, that is, close to pure red can be gradually increased. As a result, the red color can be effectively emphasized. According to the present invention, since the red color can be clearly emphasized, the visibility of the signal can be enhanced and the autumn leaves can be enjoyed.

Further, the TA is preferably 0.14 or more and less than 0.30, and more preferably 0.15 or more and less than 0.27. As a result, the transmittance of the color in the wavelength range A, that is, yellowish or orangeish red, can be sufficiently suppressed.

Further, the TB is preferably 0.40 or more and less than 0.75, and more preferably 0.45 or more and less than 0.72. Thereby, the color in the wavelength region B, that is, the transmittance close to pure red can be gradually increased.

As described above, the TA is 0.14 or more and less than 0.30, and the TB is 0.40 or more and less than 0.75, so that the red color can be emphasized more effectively.

The average transmittance in the wavelength range of 630 nm or more and 780 nm or less may be 70% or less, preferably 30% or more, and more preferably 54% or more. Thereby, the effect of the present invention can be obtained more remarkably.

The light absorption spectrum as described above can be obtained, for example, by adjusting the type and content of the light absorber.

The first light absorber is preferably a merocyanine-based dye or a tetraazaporphyrin metal complex-based dye, and the second light-absorbing agent is preferably an azo-based dye. In this case, the content of the first light absorber in the specific wavelength absorbing layer 11 is 0.001 w% or more and 0.1 w% or less, and the content of the second light absorber in the polarizing layer 12 is 0.001 w%. It is more preferably 0.1 w% or less. As a result, the optical sheet 1 can have a light absorption spectrum as described above.

Further, the optical sheet 1 preferably has an L * value of 30 or more and 60 or less, and more preferably 35 or more and 55 or less. This makes it possible to emphasize red color more effectively.

Further, the optical sheet 1 preferably has an a * value of -15 or more and 25 or less, and more preferably -10 or more and 20 or less. This makes it possible to emphasize red color more effectively.

Further, the optical sheet 1 preferably has a b * value of −10 or more and 30 or less, and more preferably −5 or more and 25 or less. This makes it possible to emphasize red color more effectively.

In the present specification, the L * value, the a * value, and the b * value are the values measured by "V-760" manufactured by JASCO Corporation.

Next, a method for manufacturing an optical sheet and a method for manufacturing an optical component will be described. In the following, a case where an optical sheet is manufactured by using an extrusion method will be described as an example.

(Manufacturing method of optical sheet)
First, the optical sheet manufacturing apparatus used in this manufacturing method will be described.

FIG. 3 is a side view schematically showing an optical sheet manufacturing apparatus for manufacturing the optical sheet shown in FIG. 1. FIG. 4 is a cross-sectional view schematically showing an optical component manufacturing apparatus for manufacturing the optical component shown in FIG. 1. In the following description, the upper side in FIG. 4 is referred to as "upper" and the lower side is referred to as "lower".

The optical sheet manufacturing apparatus 100 shown in FIG. 3 has a sheet supply unit 200 and a sheet forming unit 300.

In the present embodiment, the sheet supply unit 200 includes an extruder 210 and a T-die 220 connected to the molten resin discharge unit of the extruder 210 via a pipe. The T-die 220 supplies the molten or softened strip-shaped sheet 1'to the sheet forming portion 300.

The T-die 220 is an extrusion-molded portion that extrudes a sheet 1'in a molten state or a softened state into a strip-shaped sheet by an extrusion method. The T-die 220 is loaded with the constituent materials constituting the above-mentioned optical sheet 1 in a molten state, and by extruding the melted material from the T-die 220, the strip-shaped sheet 1'is continuously sent out. Is done.

The sheet forming unit 300 has a touch roll 310, a cooling roll 320, and a subsequent cooling roll 330. Each of these rolls is configured to rotate independently by a motor (driving means) (not shown), and is cooled by the rotation of these rolls so that they are continuously sent out. By continuously feeding the sheet 1'to the sheet forming portion 300, the surface of the sheet 1'is flattened and the sheet 1'is set to a desired thickness and cooled. Then, the specific wavelength absorption layer 11 is obtained by cutting the cooled sheet 1'to a predetermined length.

The optical sheet of the present embodiment is manufactured by the method of manufacturing an optical sheet using the optical sheet manufacturing apparatus 100 as described above.

The production of an optical sheet includes an extrusion process, a molding process, and a cooling process.
First, the strip-shaped molten or softened sheet 1'is extruded (extrusion step). In this extrusion step, the extruder 210 is loaded with the constituent material of the specific wavelength absorption layer 11. Further, the constituent material of the optical sheet 1 is in a molten or softened state in the extruder 210.

Next, the surface of the sheet 1'is flattened and the sheet 1'is set to a predetermined thickness (molding step). This step is performed between the touch roll 310 and the cooling roll 320.

Next, the surface of the sheet 1'is cooled (cooling step). This step is performed between the cooling roll 320 and the subsequent cooling roll 330.

Next, while stretching the polyvinyl alcohol film in a water tank, the film is dyed with an aqueous solution in which a dye (second light absorber) is dissolved, then immersed in a boric acid solution, washed with water, and dried to achieve polarization. Obtain layer 12.

Then, an adhesive to be an adhesive layer 14 is applied on one surface of the polarizing layer 12, and the specific wavelength absorption layer 11 is arranged on the adhesive. Next, the adhesive was dried and cured to obtain an optical sheet 1 on which the protective layer 13, the adhesive layer 15, the polarizing layer 12, the adhesive layer 14, and the specific wavelength absorbing layer 11 were laminated.

The optical sheet 1 can be obtained through the above steps. Next, a method for manufacturing optical components will be described.

(Manufacturing method of optical parts)
First, the optical component manufacturing apparatus used in this manufacturing method will be described.

The optical component manufacturing apparatus 400 shown in FIG. 4 has a resin supply unit 500 and a mold 600. The resin supply unit 500 is filled with, for example, polycarbonate as a lens forming material. The mold 600 has a cavity 610 and a supply port 620 that communicates the inside and outside of the cavity 610. Further, the mold 600 is composed of an upper member 630 and a lower member 640, and in an assembled state in which these are assembled, the mold 600 that defines the optical component manufacturing apparatus 400 is configured.

The optical component of the present embodiment is manufactured by the method of manufacturing an optical component using the optical component manufacturing apparatus 400 as described above.

The method for manufacturing an optical component includes an optical sheet arranging process and a lens material supply process.
First, in a state where the upper member 630 and the lower member 640 are disassembled, the optical sheet 1 is arranged on the bottom surface 641 of the lower member 640 (optical sheet arrangement step). The bottom surface 641 has a curved concave surface, whereby a curved surface can be formed on the lens 4. Further, since the optical sheet 1 has flexibility, it is arranged according to the shape of the bottom surface 641.

Next, the upper member 630 and the lower member 640 are put into an assembled state, and the molten or softened lens material is poured through the supply port 620 (lens material supply step). Then, by cooling the lens material in a molten or softened state, a laminated body in which the optical sheet 1 and the lens are laminated can be obtained.

In the above description, the so-called sheet insert method has been described as an example, but the present invention is not limited to this, and for example, even if the optical sheet 1 is laminated on a molded lens via an adhesive. good.

Although the preferred embodiment of the present invention has been described above, the present invention is not limited to the above-mentioned ones, and modifications, improvements, etc. within the range in which the object of the present invention can be achieved are included in the present invention. Is.

For example, each part constituting the optical sheet of the present invention can be replaced with an arbitrary configuration capable of exhibiting the same function.

Further, the optical sheet of the present invention may have any constituents added in addition to the above-mentioned configurations.

More specifically, for example, the optical sheet of the present invention may include an intermediate layer, a power adjusting layer for adjusting the power as a lens, and the like.

Hereinafter, the present invention will be described in more detail based on Examples.
1. 1. Examination of optical sheet 1-1. Creation of Optical Sheet [Example 1]
[1] First, with 100 parts by mass of bisphenol A type polycarbonate (manufactured by Mitsubishi Gas Chemical Co., Ltd., "Iupilon E2000FN E5100") and 0.02 parts by mass of a light absorber (manufactured by Yamada Chemical Co., Ltd., "FDB-006"). , 0.06 parts by mass of light absorber (Yamada Chemical Co., Ltd., "FDG-006") and 0.4 parts by mass of ultraviolet absorber (Adeca, "Adecastab LA-31G") are stirred and mixed. By doing so, an optical sheet forming material was prepared.

[2] Next, the optical sheet forming material was stored in the extruder 210 of the optical sheet manufacturing apparatus 100 shown in FIG. 3, melted, and extruded from the T-die 220 to obtain a sheet material. Then, the sheet material was cooled and molded by the sheet molding unit 300 to create a specific wavelength absorption layer having an average thickness of 0.3 mm.

[3] Further, as a protective layer forming material, 100 parts by mass of bisphenol A type polycarbonate (“Iupilon E2000FN E5100” manufactured by Mitsubishi Engineering Plastics Co., Ltd.) is prepared, and the protective layer forming material is an optical sheet manufacturing apparatus shown in FIG. It was stored in an extruder 210 of 100, melted, and extruded from a T-die 220 to obtain a protective layer. The thickness of the obtained protective layer was 0.325 mm.

[4] Further, while stretching a polyvinyl alcohol film (“Kuraray Vinylon # 7500” manufactured by Kuraray Co., Ltd.) in a water tank, dyeing with an aqueous solution in which a dye (second light absorber) is dissolved, and then immersing in a boric acid solution. A polarizing layer was obtained by treatment, washing with water, and drying. When the dye was dissolved, the dyes of the types shown in Table 1 were dissolved so that the blending amount was as shown in Table 1 after drying. The thickness of the obtained polarizing layer was 0.02 mm.

[5] Then, an adhesive was applied to one surface side and the other surface side of the obtained polarizing layer, and the protective layer and the specific wavelength absorption layer were arranged as shown in FIG. Then, the adhesive was dried to obtain a laminate in which a protective layer, a polarizing layer and a specific wavelength absorption layer were laminated, that is, an optical sheet.

In the light absorption spectrum of the obtained optical sheet, the average transmittance in the wavelength range of 630 nm or more and 780 nm or less was 54.1%. The average gradual increase rate TA was 0.18, and the average gradual increase rate TB was 0.51.

The transmission peak wavelength P1 was 505 nm, the absorption peak wavelength P2 was 585 nm, and the transmission peak wavelength P3 was 415 nm.

The transmittance at the transmission peak wavelength P1 is 29.0%, the transmittance at the absorption peak wavelength P2 is 6.5%, and the transmittance at the transmission peak wavelength P3 is 24.7%. Met.

The half-value width W1 was 13 nm, the half-value width W2 was 13 nm, and the half-value width W3 was 12 nm.

The L * value was 52.1, the a * value was -3.8, and the b * value was 0.5.

[Example 2]
An optical sheet of Example 2 was obtained in the same manner as in Example 1 except that the configuration of the optical sheet was changed as shown in Table 1.

[Example 3]
An optical sheet of Example 3 was obtained in the same manner as in Example 1 except that the configuration of the optical sheet was changed as shown in Table 1.

[Example 4]
An optical sheet of Example 4 was obtained in the same manner as in Example 1 except that the configuration of the optical sheet was changed as shown in Table 1.

[Example 5]
An optical sheet of Example 5 was obtained in the same manner as in Example 1 except that the configuration of the optical sheet was changed as shown in Table 1.

[Example 6]
An optical sheet of Example 6 was obtained in the same manner as in Example 1 except that the configuration of the optical sheet was changed as shown in Table 1.

[Comparative Example 1]
An optical layer of Comparative Example 1 was obtained in the same manner as in Example 1 except that the configuration of the optical sheet was changed as shown in Table 1.

[Comparative Example 2]
An optical sheet of Comparative Example 2 was obtained in the same manner as in Example 1 except that the configuration of the optical sheet was changed as shown in Table 1.

[Comparative Example 3]
An optical sheet of Comparative Example 3 was obtained in the same manner as in Example 1 except that the configuration of the optical sheet was changed as shown in Table 1.

[Comparative Example 4]
An optical sheet of Comparative Example 4 was obtained in the same manner as in Example 1 except that the configuration of the optical sheet was changed as shown in Table 1.

Further, in Table 1, a1 indicates a first light absorber (manufactured by Yamada Chemical Industry Co., Ltd., "FDB-006"), and a2 indicates a first light absorber (manufactured by Yamada Chemical Industry Co., Ltd., "FDG-005"). B1 indicates a second light absorber (Huntsman, "SOLOPHENYL BLUE FGLE 220%"), b2 indicates a second light absorber (Tokyo Aniline, "Sumilit Red 4B"), and b3 indicates. , The second light absorber (manufactured by Taiwan Yongkou Co., Ltd., "EVERDIRECT SUPRA ORANGE 2GL"), and b4 indicates the second light absorber (manufactured by Kyowa Sangyo Co., Ltd., "LA1120 Chemistry").

1-2. Evaluation The optical sheets of each example and each comparative example were evaluated by the following methods.

(Evaluation of red emphasis)
A photograph of the red model was taken through the optical sheet manufactured as described above, and it was confirmed whether each of the 10 persons had the effect of enhancing the red color.
⊚: Effective for 10 out of 10 people.
〇: Effective for 6 to 9 out of 10 people.
Δ: Effective for 2 to 5 out of 10 people.
×: Effective for 1 out of 10 people.

(Evaluation of distinctiveness of other colors)
A photograph of the modeled object was taken through the optical sheet manufactured as described above, and it was confirmed by 10 people whether the color of the modeled object could be correctly identified.
⊚: 10 out of 10 people could be identified.
〇: 6 to 9 out of 10 people could be identified.
Δ: 2 to 5 out of 10 people could be identified.
X: 1 out of 10 people could be identified.

The evaluation results of the optical sheets of each Example and each Comparative Example obtained as described above are shown in Table 1 below.

As shown in Table 1, in the optical sheet in each example, the red color could be emphasized more than in each comparative example, and the result was satisfactory for each comparative example.

1 Optical sheet 1'Sheet 2 Frame 3 Lens with optical sheet 4 Lens 5 Mounting part 6 Brim 7 Light transmissive member 10 Optical component 10'Optical component 11 Specific wavelength absorption layer 12 Polarizing layer 13 Protective layer 14 Adhesive layer 15 Adhesive Layer 21 Rim part 22 Bridge part 23 Temple part 24 Nose pad part 100 Optical sheet manufacturing equipment 200 Sheet supply part 210 Extruder 220 T-die 300 Sheet forming part 310 Touch roll 320 Cooling roll 330 Later cooling roll 400 Optical parts manufacturing equipment 500 Resin Supply unit 600 Mold 610 Cavity 620 Supply port 630 Upper member 640 Lower member 641 Bottom surface

Such an object is achieved by the present invention of the following (1) to ( 9 ).
(1) A light absorbing layer composed of a resin and a material containing at least one kind of first light absorber and absorbing light in a specific wavelength range in the visible light region, and at least one kind of second light absorber. An optical sheet comprising, and having a polarizing layer having a polarizing function.
In the light absorption spectrum of the optical sheet,
A first peak having a transmittance transmission peak wavelength P1 in a wavelength range of 480 nm or more and 530 nm or less, a second peak having a transmittance absorption peak wavelength P2 in a wavelength range of 550 nm or more and 610 nm or less, and a wavelength of 400 nm or more and 450 nm or less. It has a transmission peak wavelength P3 with transmittance in the region .
The average transmittance in the wavelength range of 630 nm or more and 780 nm or less is 70% or less, and in the wavelength range A of 630 nm or more and 700 nm or less, the transmittance gradually increases toward the long wavelength side, and the transmittance is gradually increased toward the long wavelength side, and the wavelength range B of 700 nm or more and 780 nm or less. In, the transmittance gradually increases toward the long wavelength side,
An optical sheet characterized in that TA <TB is satisfied when the average gradual increase rate of the transmittance in the wavelength region A is TA and the average gradual increase rate of the transmittance in the wavelength region B is TB.

( 9 ) With the base material
An optical component laminated on the substrate and provided with the optical sheet according to any one of (1) to ( 8 ) above.

Claims (10)

It is composed of a material containing a resin and at least one first light absorber, and contains a light absorption layer that absorbs light in a specific wavelength range in the visible light region and at least one second light absorber. An optical sheet comprising a polarizing layer having a polarizing function.
In the light absorption spectrum of the optical sheet,
It has a first peak having a transmittance transmission peak wavelength P1 in a wavelength range of 480 nm or more and 530 nm or less, and a second peak having a transmittance absorption peak wavelength P2 in a wavelength range of 550 nm or more and 610 nm or less.
The average transmittance in the wavelength range of 630 nm or more and 780 nm or less is 70% or less, and in the wavelength range A of 630 nm or more and 700 nm or less, the transmittance gradually increases toward the long wavelength side, and the transmittance is gradually increased toward the long wavelength side, and the wavelength range B of 700 nm or more and 780 nm or less. In, the transmittance gradually increases toward the long wavelength side,
An optical sheet characterized in that TA <TB is satisfied when the average gradual increase rate of the transmittance in the wavelength region A is TA and the average gradual increase rate of the transmittance in the wavelength region B is TB. The TA is 0.14 or more and less than 0.30.
The optical sheet according to claim 1, wherein the TB is 0.40 or more and less than 0.75. The optical sheet according to claim 1 or 2, wherein the transmittance at the transmission peak wavelength P1 is 8% or more and 40% or less. The optical sheet according to any one of claims 1 to 3, wherein the transmittance at the absorption peak wavelength P2 is 1% or more and 20% or less. The optical sheet according to claim 4, wherein the first light absorber is at least one of a quinoline dye, an anthraquinone dye, perylene dye, polymethine dye, porphyrin complex dye, and phthalocyanine dye. The second light absorber is at least one of an azo dye, a stilbene dye, a thiazole dye, a dioxazine dye, a phthalocyanine dye, a disazo dye, a trisazo dye, and a metal complex salt azo dye. Item 4. The optical sheet according to Item 4. The optical sheet according to any one of claims 1 to 6, wherein the half width at the first peak is 10 nm or more and 40 nm or less. The optical sheet according to any one of claims 1 to 7, wherein the half width at the second peak is 10 nm or more and 30 nm or less. The optical sheet according to any one of claims 1 to 8, which has a third peak having a transmittance peak wavelength P3 in a wavelength range of 400 nm or more and 450 nm or less in the light absorption spectrum of the optical sheet. With the base material
An optical component laminated on the substrate and comprising the optical sheet according to any one of claims 1 to 9.

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