Optical laminate, polarizing lens, and eyewear

Abstract

The present invention relates to an optical laminate (101, 102, 103) comprising: a light reflection layer (20) including at least one cholesteric liquid crystal layer (10, 11) having an absolute value (|ΔR1-R2|) of the difference between an average reflectance (R1) in a wavelength range from 500 nm to 700 nm and an average reflectance (R2) in a wavelength range from more than 700 nm to 900 nm of 10.0 or less; a polarization element (23) including at least one dichroic dye; and a first support (21) and a second support (22) sandwiching the light reflection layer (20) and the polarization element (23). The first support (21), the light reflection layer (20), the polarization element (23), and the second support (22) are laminated in this order. A first adhesive layer (25) is disposed between the light reflection layer (20) and the first support (21), and a second adhesive layer (24) is disposed between the polarization element (23) and the second support (22). The first adhesive layer (25) contains at least one of a hue adjustment colorant and a specific wavelength absorption colorant.

Description

Optical laminate, polarized lens and eyewear

[0001] The present invention relates to an optical laminate, and a polarized lens and eyewear (sunglasses, goggles, helmet visors, etc.) using the same.

[0002] Eyewear (sunglasses, goggles, visors, etc.) are used to reduce glare caused by light reflected from water surfaces, road surfaces, snow surfaces, etc. For example, in sunglasses, the lenses are colored with a pigment or the like, which absorbs the reflected light. This reduces the amount of light incident on the eyes of the wearer of the sunglasses, thereby reducing glare. Meanwhile, since light reflected from water and snow surfaces generally tends to be polarized, polarized sunglasses are particularly effective against this reflected light. Polarized sunglasses are designed to effectively absorb light in the direction of polarization, so they can reduce glare and improve visibility without significantly reducing the amount of light incident on the eyes.

[0003] The optical film used in polarized sunglasses typically has a structure in which a polarizing element is sandwiched between a support material such as polycarbonate. Polarized sunglasses can be produced by processing such an optical film into a desired shape and fitting it into a frame. The polarizing element is a film in which a dichroic dye, such as a dichroic dye or an iodine-polyvinyl alcohol (PVA) complex, is uniaxially oriented together with a polymer such as PVA, and polarizing elements of various colors can be obtained depending on the color of the dye used. In the case of regular sunglasses, the polarizing element is often colored gray to impart polarization to the entire visible light range.

[0004] In order to add design features to polarized sunglasses or to further improve visibility, a multilayer film may be vapor-deposited on the surface (Patent Document 1). By applying a multilayer film, the light reflected from the surface of the sunglasses appears to others not wearing the sunglasses in metallic tones such as blue, green, and red, while to the wearer, specific light is reflected, reducing glare and further improving visibility of the scenery.

[0005] On the other hand, methods for imparting reflected light with a metallic color tone using organic materials without using a multilayer film include a method using a light-reflecting polarizing film as described in Patent Document 3 and a cholesteric liquid crystal layer as described in Patent Document 2.

[0006] A reflective polarizing film utilizes light interference to transmit only the P wave of incident light and reflect the S wave that does not pass through the polarizing plate as a linearly polarized component. In Patent Document 3, a colored absorptive polarizing film layer, a reflective polarizing film layer, and an absorptive polarizing film layer are laminated in this order from the light incident side, thereby providing a mirror lens that allows the lens exterior color and transmission color to be selected as desired.

[0007] Cholesteric liquid crystals are liquid crystal molecules that are helically oriented, and have the ability to selectively reflect circularly polarized light components in a specific wavelength range that are oriented in the same direction as the helical direction of the liquid crystal molecules, depending on the length of the helical pitch. Optical laminates using cholesteric liquid crystal layers in which the helical orientation is fixed so that light is reflected in a desired wavelength range exhibit vivid reflected light and can add decorativeness to various components (Patent Document 2).

[0008] It is also known that by using a liquid crystal material with a continuously changing helical pitch, it is possible to achieve flat wavelength characteristics in the reflection characteristics of a cholesteric liquid crystal layer across the visible light range with a single layer of cholesteric liquid crystal (Non-Patent Document 1).

[0009] JP 2000-066149 A JP 2001-180200 A International Publication No. 2013 / 051489

[0010] Journal of the Japanese Liquid Crystal Society Vol. 2 No. 2 Published April 25, 1998

[0011] However, the method described in Patent Document 1 has handling problems, such as the difficulty in removing sebum and other substances that adhere to the multilayer film, and the multilayer film may peel off in places exposed to moisture such as the sea or sea breezes. To prevent this, a method of providing the multilayer film inside the support material, i.e., between the polarizing element and the support material, is considered. However, because the reflective performance of the multilayer film is exerted by the difference in refractive index between each layer, it is difficult to obtain reflective performance equivalent to that of the outer air interface. Furthermore, because the multilayer film is made of inorganic materials, it is difficult to ensure sufficient adhesion to the polarizing element, which is an organic material.

[0012] In the method described in Patent Document 3, the reflected light from the reflective polarizing film becomes S-waves due to its characteristics, so the reflected light is cut off for other people wearing polarized sunglasses, which may impair the design.

[0013] Furthermore, in the method described in Patent Document 2, the reflection characteristics of the cholesteric liquid crystal layer are angle-dependent, and the color tone changes when the cholesteric liquid crystal layer is observed at different angles. Therefore, when the reflected color of an optical laminate having a cholesteric liquid crystal layer is visually observed from 0° to 90°, for example, in addition to a metallic red color, the reflected color may be visually recognized as changing to yellow or orange depending on the viewing angle from surrounding observers.

[0014] Furthermore, in eyewear applications, these cholesteric liquid crystal layers are generally formed into a curved shape and then integrally molded with a resin to produce a polarized lens, so the cholesteric liquid crystal layer is observed in a curved state. Therefore, even when the cholesteric liquid crystal layer is used, the surface of the polarized sunglasses is observed in an angle-dependent state, and the color tone of the surface is not uniform, resulting in the problem of appearing colored.

[0015] The present invention aims to provide an optical laminate that has a curved surface and exhibits a desired reflection hue with little change in color even when observed from various angles, and to provide polarized lenses and eyewear that use the same.

[0016] An optical laminate according to an embodiment of the present invention comprises a light-reflecting layer including at least one cholesteric liquid crystal layer in which the absolute value of the difference (|ΔR1-R2|) between the average reflectance (R1) in a wavelength range of 500 nm or more and 700 nm or less and the average reflectance (R2) in a wavelength range of more than 700 nm and 900 nm or less is 10.0 or less; a polarizing element including at least one kind of dichroic dye; and a first support and a second support which sandwich the light-reflecting layer and the polarizing element, wherein the first support, the light-reflecting layer, the polarizing element, and the second support are laminated in this order, a first adhesive layer is disposed between the light-reflecting layer and the first support, and a second adhesive layer is disposed between the polarizing element and the second support, and the first adhesive layer includes at least one kind of hue-adjusting dye and a specific wavelength-absorbing dye.

[0017] According to the present invention, it is possible to provide an optical laminate that has a curved surface and exhibits a desired reflection hue with little change in color even when observed from various angles, as well as polarized lenses and eyewear using the same.

[0018] FIG. 1 is a schematic diagram showing one embodiment of the optical laminate of the present invention. FIG. 2 is a schematic diagram showing another embodiment of the optical laminate of the present invention. FIG. 3 is a schematic diagram showing another embodiment of the optical laminate of the present invention. FIG. 4 is a conceptual diagram of an apparatus for measuring the angle dependence of the reflection hue exhibited by the optical laminate of the present invention. FIG. 5 shows the reflection spectra of cholesteric liquid crystal layers L-WSi / R-WSi, R550 and R650. FIG. 6 shows the reflection spectra of the optical laminates produced in Example 1 and Comparative Example 1.

[0019] Hereinafter, embodiments according to the present invention will be described in detail. Note that the following embodiments are examples of some typical embodiments of the present invention, and various modifications can be made within the scope of the present invention.

[0020] <Optical Laminate> As shown in FIG. 1 , an optical laminate 101 according to one embodiment of the present invention includes a light-reflecting layer 20, a polarizing element 23, a first support 21, and a second support 22, and is arranged in the following order from the external light incident side: first support 21, light-reflecting layer 20, polarizing element 23, and second support 22. The light-reflecting layer 20 and polarizing element 23 are sandwiched between the first support 21 and the second support 22. A first adhesive layer 25 is arranged between the first support 21 and the light-reflecting layer 20, and a second adhesive layer 24 is arranged between the second support 22 and the polarizing element 23. The light-reflecting layer 20 also includes a cholesteric liquid crystal layer 10 exhibiting predetermined optical properties. The first adhesive layer 25 and the second adhesive layer 24 are different adhesive layers, with the first adhesive layer 25 being a hue-adjusting dye-containing adhesive layer and the second adhesive layer 24 being a colorless and transparent adhesive layer. The external light incident side refers to the incident light side when the optical laminate is provided in a polarized lens of eyewear. An adhesive layer (not shown) is also provided between the light reflecting layer 20 and the polarizing element 23.

[0021] 2, an optical laminate 102 according to another embodiment of the present invention has the same laminate structure as the optical laminate shown in Fig. 1, except that the light-reflecting layer 20 includes a cholesteric liquid crystal layer 10 and a further cholesteric liquid crystal layer 11. In this case, the liquid crystal molecules of the cholesteric liquid crystal layer 10 and the cholesteric liquid crystal layer 11 are oriented in different helical directions, and one of the cholesteric liquid crystal layer 10 and the cholesteric liquid crystal layer 11 is at least one cholesteric liquid crystal layer whose helical direction is right-handed (R-form), and the other is at least one cholesteric liquid crystal layer whose helical direction is left-handed (L-form).

[0022] As shown in Fig. 3, an optical laminate 103 according to another embodiment of the present invention has the same laminate structure as the optical laminate shown in Fig. 2, except that a first adhesive layer 25 is disposed between the second support 22 and the polarizing element 23. That is, two hue-adjusting dye-containing adhesive layers are disposed in the optical laminate 103. In this case, the hue-adjusting dye-containing adhesive layers of the first adhesive layers 25 may be the same adhesive layer or may be different adhesive layers.

[0023] (Light-Reflecting Layer) The light-reflecting layer used in the present invention includes at least one cholesteric liquid crystal layer. Cholesteric liquid crystal is composed of nematic liquid crystal with chirality or a compound in which a chiral agent is added to nematic liquid crystal. Since the helical orientation or reflection wavelength can be freely designed depending on the type or amount of chiral agent, cholesteric liquid crystal obtained by adding a chiral agent to nematic liquid crystal is preferred. Unlike liquid crystals that are controlled by an electric field, nematic liquid crystals are used with their helical orientation state fixed, so a nematic liquid crystal monomer having a polymerizable group is preferred.

[0024] Nematic liquid crystal monomers with polymerizable groups are compounds that contain polymerizable groups within their molecules and exhibit liquid crystallinity within a specific temperature or concentration range. Examples of polymerizable groups include (meth)acryloyl, vinyl, chalconyl, cinnamoyl, and epoxy groups. Furthermore, to exhibit liquid crystallinity, it is preferable to have a mesogenic group within the molecule. Mesogenic groups refer to rod- or plate-shaped substituents such as biphenyl, terphenyl, (poly)benzoic acid phenyl ester, (poly)ether, benzylideneaniline, and acenaphthoquinoxaline groups, or discotic substituents such as triphenylene, phthalocyanine, and azacrown groups, i.e., groups capable of inducing liquid crystal phase behavior. Liquid crystal compounds with rod- or plate-shaped substituents are known in the art as calamitic liquid crystals. Specific examples of such nematic liquid crystal monomers having a polymerizable group include the polymerizable liquid crystals described in JP-A Nos. 2003-315556 and 2004-29824, the PALIOCOLOR series (manufactured by BASF), the RMM series (manufactured by Merck), etc. These nematic liquid crystal monomers having a polymerizable group can be used alone or in combination.

[0025] The chiral agent can induce right-handed (R-configuration) or left-handed (L-configuration) helical orientation in the nematic liquid crystal monomer having a polymerizable group, and like the nematic liquid crystal monomer having a polymerizable group, a compound having a polymerizable group is preferred. Examples of such chiral agents include Paliocolor LC756 (manufactured by BASF) and the compounds described in JP 2002-179668 A. The type of chiral agent determines the direction of the reflected circularly polarized light, and further, the reflection wavelength of the cholesteric liquid crystal layer can be changed depending on the amount of chiral agent added to the nematic liquid crystal. For example, the more the amount of chiral agent added, the more likely it is that a cholesteric liquid crystal layer will reflect shorter wavelengths. The amount of chiral agent added varies depending on the type of chiral agent and the wavelength to be reflected, but in order to adjust the central reflection wavelength of the cholesteric liquid crystal layer for ordinary light to a desired wavelength range, the amount is preferably 0.5 parts by mass or more and 30 parts by mass or less, more preferably 1 part by mass or more and 20 parts by mass or less, and even more preferably 3 parts by mass or more and 10 parts by mass or less, per 100 parts by mass of nematic liquid crystal monomer having a polymerizable group.

[0026] Furthermore, it is also possible to add a polymerizable compound that does not have liquid crystallinity but can react with a nematic liquid crystal monomer having a polymerizable group, such as a polymerizable compound that forms an ultraviolet-curable resin. Examples of ultraviolet curable resins include dipentaerythritol hexa(meth)acrylate, a reaction product of dipentaerythritol penta(meth)acrylate and 1,6-hexamethylene diisocyanate, a reaction product of a triisocyanate having an isocyanuric ring and pentaerythritol tri(meth)acrylate, a reaction product of pentaerythritol tri(meth)acrylate and isophorone diisocyanate, dipentaerythritol penta(meth)acrylate, dipentaerythritol tetra(meth)acrylate, pentaerythritol tetra(meth)acrylate, pentaerythritol tri(meth)acrylate, trimethylolpropane tri(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, tris(acryloxyethyl)isocyanurate, tris(metha[pi] ... tris(acryloxyethyl)isocyanurate, reaction products of glycerol triglycidyl ether and (meth)acrylic acid, caprolactone-modified tris(acryloxyethyl)isocyanurate, reaction products of trimethylolpropane triglycidyl ether and (meth)acrylic acid, triglycerol di(meth)acrylate, reaction products of propylene glycol diglycidyl ether and (meth)acrylic acid, polypropylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, pentaerythritol di(meth)acrylate, reaction products of 1,6-hexanediol diglycidyl ether and (meth)acrylic acid, 1,6-Hexanediol di(meth)acrylate, glycerol di(meth)acrylate, reaction products of ethylene glycol diglycidyl ether and (meth)acrylic acid, reaction products of diethylene glycol diglycidyl ether and (meth)acrylic acid, bis(acryloxyethyl)hydroxyethyl isocyanurate, bis(methacryloxyethyl)hydroxyethyl isocyanurate, reaction products of bisphenol A diglycidyl ether and (meth)acrylic acid, tetrahydrofurfuryl (meth)acrylate, caprolactone-modified tetrahydrofurfuryl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, polypropylene glycol (meth)acrylate, polyethylene glycol (meth)acrylate, phenoxyhydroxypropyl (meth)acrylate ) acrylate, acryloylmorpholine, methoxypolyethylene glycol (meth)acrylate, methoxytetraethylene glycol (meth)acrylate, methoxytriethylene glycol (meth)acrylate, methoxyethylene glycol (meth)acrylate, methoxyethyl (meth)acrylate, glycidyl (meth)acrylate, glycerol (meth)acrylate, ethyl carbitol (meth)acrylate, 2-ethoxyethyl (meth)acrylate, N,N-dimethylaminoethyl (meth)acrylate, 2-cyanoethyl (meth)acrylate, a reaction product of butyl glycidyl ether and (meth)acrylic acid, butoxytriethylene glycol (meth)acrylate, or butanediol mono(meth)acrylate, which may be used alone or in combination. These UV-curable resins without liquid crystallinity must be added to an extent that the nematic liquid crystal monomer having a polymerizable group does not lose its liquid crystallinity, and are preferably added in an amount of 0.1 parts by mass or more and 20 parts by mass or less, more preferably 1.0 parts by mass or more and 10 parts by mass or less, per 100 parts by mass of the nematic liquid crystal monomer having a polymerizable group.

[0027] When the nematic liquid crystal monomer having a polymerizable group or other polymerizable compound is an ultraviolet curable resin, a photopolymerization initiator is added to the composition containing these compounds in order to cure them by ultraviolet light. Examples of the photopolymerization initiator include acetophenone compounds such as 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropane-1, 1-hydroxycyclohexyl phenyl ketone, 4-(2-hydroxyethoxy)-phenyl(2-hydroxy-2-propyl)ketone, 1-(4-dodecylphenyl)-2-hydroxy-2-methylpropan-1-one, 1-(4-isopropylphenyl)-2-hydroxy-2-methylpropan-1-one, 2-hydroxy-2-methyl-1-phenylpropan-1-one, and diethoxyacetophenone; benzoin compounds such as benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, and 2,2-dimethoxy-2-phenylacetophenone; benzoylbenzoic acid, methyl benzoylbenzoate, 4- Benzophenone compounds such as phenylbenzophenone, hydroxybenzophenone, 4-benzoyl-4'-methyldiphenyl sulfide, and 3,3'-dimethyl-4-methoxybenzophenone (manufactured by Nippon Kayaku Co., Ltd., Kayacure (registered trademark) MBP); and thioxanthone compounds such as thioxanthone, 2-chlorothioxanthone (manufactured by Nippon Kayaku Co., Ltd., Kayacure (registered trademark) CTX), 2-methylthioxanthone, 2,4-dimethylthioxanthone (manufactured by Nippon Kayaku Co., Ltd., Kayacure (registered trademark) RTX), isopropylthioxanthone, 2,4-dichlorothioxanthone (manufactured by Nippon Kayaku Co., Ltd., Kayacure (registered trademark) CTX), 2,4-diethylthioxanthone (manufactured by Nippon Kayaku Co., Ltd., Kayacure (registered trademark) DETX), and 2,4-diisopropylthioxanthone (manufactured by Nippon Kayaku Co., Ltd., Kayacure (registered trademark) DITX).Preferably, for example Omnirad® TPO, Omnirad® TPO-L, Omnirad® OXE01, Omnirad® OXE02, Omnirad® 1300, Omnirad® 184, Omnirad® 369, Omnirad® 379, Omnirad® 819, Omnirad® 127, Omnirad® 907 or Omnirad® 1173 (all available from IGM Resins) are used. B.V.), and particularly preferred are Omnirad (registered trademark) TPO, Omnirad (registered trademark) TPO-L, Omnirad (registered trademark) OXE01, Omnirad (registered trademark) OXE02, Omnirad (registered trademark) 1300, and Omnirad (registered trademark) 907. These photopolymerization initiators can be used alone or in combination in any desired ratio.

[0028] When a benzophenone compound or a thioxanthone compound is used as the photopolymerization initiator, an auxiliary agent can be used in combination to promote the photopolymerization reaction. Examples of such auxiliary agents include amine compounds such as triethanolamine, methyldiethanolamine, triisopropanolamine, n-butylamine, N-methyldiethanolamine, diethylaminoethyl methacrylate, Michler's ketone, 4,4'-diethylaminophenone, ethyl 4-dimethylaminobenzoate, (n-butoxy)ethyl 4-dimethylaminobenzoate, and isoamyl 4-dimethylaminobenzoate.

[0029] The amounts of the photopolymerization initiator and auxiliary added are preferably within a range that does not affect the liquid crystallinity of the liquid crystal composition containing the nematic liquid crystal monomer, and the amounts are preferably 0.5 to 10 parts by mass, more preferably 2 to 8 parts by mass, relative to 100 parts by mass of the ultraviolet-curable compound in the liquid crystal composition. The amount of the auxiliary added is preferably 0.5 to 2 times the amount of the photopolymerization initiator.

[0030] The liquid crystal composition further contains a solvent. Such a solvent is not particularly limited as long as it can dissolve the liquid crystal compound, chiral agent, etc. used. Examples include methyl ethyl ketone, toluene, methyl isobutyl ketone, cyclopentanone, acetone, anisole, etc., and preferably cyclopentanone, which has good solubility. These solvents can be added in any ratio, and one type may be added alone, or multiple solvents may be used in combination. These solvents are dried and removed in a drying oven or drying equipment of a film coating device.

[0031] A method for preparing a cholesteric liquid crystal layer using cholesteric liquid crystals involves, for example, adding a necessary amount of a right-handed or left-handed chiral agent to a nematic liquid crystal monomer having a polymerizable group so as to reflect the desired wavelength. These are then dissolved in a solvent, and a photopolymerization initiator is added. The solution is then applied to a plastic substrate such as a polyethylene terephthalate (PET) film to a thickness as uniform as possible. The solvent is then removed by heating, and the coating is left for a certain period of time under temperature conditions such that the cholesteric liquid crystals on the substrate become oriented at the desired helical pitch. By subjecting the surface of the plastic substrate to an orientation treatment such as rubbing or stretching before applying the solution, the orientation of the cholesteric liquid crystals can be made more uniform, thereby reducing the haze value of each cholesteric liquid crystal layer. Next, while the helical pitch is continuously changed so as to reflect light from the visible light region to the near-infrared region, ultraviolet light is irradiated from a high-pressure mercury lamp or the like to fix the orientation, resulting in a silver-colored cholesteric liquid crystal layer. An example of a method for continuously changing the helical pitch is the method described in JP 2003-139953 A, in which the atmosphere during curing by ultraviolet irradiation or the surface irradiated with ultraviolet light is oriented in a specific direction. In this case, the desired reflection band can be adjusted by adjusting the oxygen concentration in the atmosphere during ultraviolet irradiation, the amount of ultraviolet light irradiated, the irradiation time, the irradiation temperature, and the like. To obtain a silver-colored cholesteric liquid crystal layer, the reflection band is at least in the range of 380 nm to 850 nm, preferably in the range of 380 nm to 900 nm, and more preferably in the range of 380 nm to 1000 nm.

[0032] The film thickness after forming the cholesteric liquid crystal layer is preferably 1 μm or more and 15 μm or less, more preferably 2 μm or more and 10 μm or less.

[0033] In the structure of the cholesteric liquid crystal layer of the light reflection layer, in order to impart high polarization characteristics when laminating the light reflection layer and the polarizing element according to the design of the eyewear, the light reflection layer may include both a cholesteric liquid crystal layer of the R form and a cholesteric liquid crystal layer of the L form. Also, when polarization characteristics are not emphasized, it may include only a light reflection layer of either the cholesteric liquid crystal layer of the R form or the cholesteric liquid crystal layer of the L form. Further, these structures are not particularly limited as long as they can exhibit the above-described effects, and any of them can be used. Since the optical characteristics do not change regardless of the lamination order for the surface of the cholesteric liquid crystal layer laminated with the polarizing element, either the L form or the R form may be used.

[0034] When the cholesteric liquid crystal layer exhibits achromatic silver color, generally, it means that a color with a shine (also called luster) like that of metallic silver is visually recognized. As an example of the reflectance waveform exhibiting such silver color, it is substantially uniformly distributed over the visible light region (wavelength range of 380 nm or more and 780 nm or less), and in terms of perception, it means a state that is visually recognized as a silver luster without color. Specifically, in the L ＊ a ＊ b ＊ hue values a ＊ and b ＊ based on the color space (CIE 1976), a ＊ = -2 to +2, b ＊ is a hue of about -4 to +4.

[0035] The reflectance of the cholesteric liquid crystal layer depends on the design of the eyewear, but the average reflectance in the visible light region (380 nm to 780 nm) is preferably at least 10% or more, more preferably 20% or more. The optical laminate may also include both R-type and L-type cholesteric liquid crystal layers. In this case, the average reflectance in the visible light region is preferably at least 15% or more, more preferably 25% or more. This allows for a bright, mirror-like surface with a metallic luster.

[0036] Because the cholesteric liquid crystal layer has angle-dependent reflectance, it is preferable that the reflectance be substantially uniform across the wavelength range of the visible light region and further across the near-infrared region (wavelengths of 781 nm or greater). The angular dependency is known to be a phenomenon caused by the complex layer structure of the cholesteric liquid crystal layer due to the angular relationship between the light incident on the cholesteric liquid crystal layer and the light reflected therefrom, resulting in a shift of the entire reflected waveform toward shorter wavelengths. Therefore, the waveform structure in the long wavelength region shifted by this shift causes coloring. Therefore, since the cholesteric liquid crystal layer has equivalent reflectance characteristics in the near-infrared region, the characteristics are directly shifted to the visible light region, allowing the layer to function as a light-reflecting layer with minimal coloring.

[0037] Furthermore, in consideration of the above-mentioned waveform shift band, the absolute value (also referred to as |ΔR1-R2|) of the difference (ΔR1-R2) between the average reflectance in the wavelength range of 500 nm or more and 700 nm or less (hereinafter referred to as R1) and the average reflectance in the wavelength range of more than 700 nm and less than 900 nm (hereinafter referred to as R2) is 10.0 or less, preferably 5.0 or less, and more preferably 3.0 or less. When such a difference in average reflectance (also referred to as reflectance difference) is within the above-mentioned range, the reflective properties in the visible light region and the near-infrared region are substantially uniform across these wavelength ranges, thereby providing an achromatic silver color that is almost or completely free of coloration even when wavelength shift due to angle dependence occurs. On the other hand, when the reflectance difference exceeds 10, as described above, since the cholesteric liquid crystal layer has reflective properties in the near-infrared region, coloring of the cholesteric liquid crystal layer due to angle dependence can be reduced, but a sufficiently achromatic color tone cannot be obtained.

[0038] Furthermore, even when the wavelength shift band includes both R-type and L-type cholesteric liquid crystal layers, the reflectance difference is within 10, preferably within 5, and more preferably within 3. By providing two or more cholesteric liquid crystal layers, it is possible to impart a bright surface with a mirror-like metallic luster, and to impart an achromatic silver tone that is almost or completely free of coloration even when a wavelength shift due to angle dependency occurs.

[0039] The change in the reflective hue of the cholesteric liquid crystal layer is evaluated, for example, by the hue difference at each tilt angle relative to a tilt angle of 0°, and the absolute value of the hue difference is expressed as |Δa ＊ r | and |△b ＊ r| can be expressed as |△a ＊ r | and |△b ＊ Both r| are preferably within 2.0, and more preferably within 1.0. When the hue difference is within these ranges, the change in reflected hue becomes unrecognizable in visual evaluation.

[0040] Such an optical laminate has a structure in which a cholesteric liquid crystal layer and a polarizing element are sandwiched between supports, and is useful in the design and use of eyewear.

[0041] (Polarizing Element) The polarizing element contains at least one dichroic dye. Examples of such polarizing elements (also referred to as bare polarizing films) include polyvinyl alcohol (PVA) polarizing films and coated polarizing films, with PVA polarizing films being representatively suitable. A known stretching method can be used to produce a PVA polarizing film. The film can be produced by adsorbing a dye such as iodine or a dichroic dye onto a polymer film containing PVA or a derivative thereof, and then uniaxially stretching the film to approximately 2 to 5 times its original size. In particular, from the viewpoints of hue design and designability, it is preferable to use a dichroic dye. Furthermore, from the viewpoint of heat resistance, it is preferable to use a direct dye containing an azo dye having a sulfonic acid group.

[0042] Examples of dichroic dyes include C.I. Direct Yellow 12, C.I. Direct Yellow 28, C.I. Direct Yellow 44, C.I. Direct Yellow 142, C.I. Direct Orange 26, C.I. Direct Orange 39, C.I. Direct Orange 71, C.I. Direct Orange 107, C.I. Direct Red 2, C.I. Direct Red 31, C.I. Direct Red 79, and C.I. Direct Red 81, C. I. Direct Red 117, C. I. Direct Red 247, C. I. Direct Green 80, C. I. Direct Green 59, C. I. Direct Blue 71, C. I. Direct Blue 78, C. I. Direct Blue 168, C. I. Direct Blue 202, C. I. Direct Violet 9, C. I. Direct Violet 51, C. I. Direct Brown 106, C. I. Direct Brown 223. The dichroic dyes may be used alone or in combination of two or more kinds.

[0043] Alternatively, the dichroic dye may be a dye that can be produced by a known method. Examples of known methods include the method described in JP-A-3-12606 and the method described in JP-A-59-145255. Commercially available dyes include Kayafect (registered trademark) Violet P Liquid, Kayafect (registered trademark) Yellow Y, Kayafect (registered trademark) Orange G, Kayafect (registered trademark) Blue KW, and Kayafect (registered trademark) Blue Liquid 400 (all manufactured by Nippon Kayaku Co., Ltd.).

[0044] At least two of the dichroic dyes described above are blended together, and optical properties (mainly luminosity-corrected single transmittance Ys and luminosity-corrected polarization degree Py), hue (e.g., CIE 1976 color space (L ＊ s, a ＊ s, b ＊ s) can be designed.

[0045] The polarizing element used in the present invention preferably has optical properties of a luminous efficiency-corrected single transmittance Ys of 25% to 45% and a luminous efficiency-corrected polarization degree of 90% or more, or a luminous efficiency-corrected single transmittance Ys of 40% to 60% and a luminous efficiency-corrected polarization degree of 60% or less, and preferably has a neutral gray hue from the viewpoint of not affecting the field of vision of the eyewear wearer. Gray-based hues include intermediate colors between black and white (generally called gray or achromatic colors) as well as hues with a slight tint, and specifically, the L obtained from the transmittance of the polarizing element alone. ＊ a ＊ b ＊ Hue value a in color space (CIE 1976) ＊ s and b ＊Each of s is preferably in the range of −5.0 to 5.0 (including 0), and more preferably in the range of −3.0 to 3.0 (including 0). Using a polarizing element having such a hue value makes it easier to perform color design using a hue-adjusting dye, as described below. For example, commercially available polarizing elements for polarized sunglasses containing dichroic dyes include Grey type, NYSH-30, KF-60, etc. (all manufactured by Nippon Kayaku Co., Ltd., each with a film thickness of 25 μm to 35 μm) made of PVA-based resin film, which can be preferably used as a polarizing element. In addition, polarizing elements having a hue such as brown may be used depending on the design of the eyewear and the visibility of the field of view.

[0046] In particular, when combining the above-mentioned cholesteric liquid crystal layer with a polarizing element, it is particularly preferable to appropriately adjust the type of dye used in the polarizing element, or, if multiple dyes are used, their blending ratio, so that the hue of the transmitted light when worn as sunglasses falls within the standard of the relative luminous efficacy attenuation factor (Q value) specified in JIS T7333, which is related to the visibility of traffic lights, for example.

[0047] Specifically, the Q value is adjusted to be equal to or greater than the following value: Q ｒｅｄ (Red): 0.8, Q ｙｅｌｌｏｗ (Yellow): 0.6, Q ｇｒｅｅｎ (Green): 0.6, Q ｂｌｕｅ (Blue): 0.4

[0048] The application of such an optical laminate that complies with the traffic light visibility standard is particularly preferable for eyewear used when driving a car. The degree of polarization (Py) is sufficient as long as it has sufficient polarization performance for sunglasses, and the degree of polarization is preferably 70% or more, more preferably 80% or more, and even more preferably 90% or more.

[0049] (Optical laminate) The structure of the optical laminate of the present invention will be exemplified below, but the optical laminate of the present invention is not limited thereto. One embodiment of the optical laminate has a laminate structure of, in order from the external light incident side, a first support / cholesteric liquid crystal layer R body (or L body) / polarizing element / second support, as shown in Figure 1. Another embodiment has a laminate structure of, in order from the external light incident side, a first support / cholesteric liquid crystal layer L body (or R body) / cholesteric liquid crystal layer R body (or L body) / polarizing element / second support, as shown in Figures 2 and 3.

[0050] A third support may be provided between the polarizing element and the cholesteric liquid crystal layer. The first support, the second support, and the third support may be made of the same material, or may be made of different materials depending on the design of the eyewear. Furthermore, each member of the optical laminate is preferably laminated via an adhesive layer.

[0051] In the process of laminating each component of the optical laminate, the cholesteric liquid crystal layer formed on a plastic substrate such as a PET film may be adhered to a polarizing element or a support, and then the plastic substrate may be removed and other layers may be sequentially laminated to form the above-described embodiment example.

[0052] (Support) The supports such as the first support, the second support, and the third support are formed of a film or sheet-like transparent resin material. Examples of such resin materials include resin materials containing polycarbonate (PC)-based resins, triacetyl cellulose (TAC)-based resins, polyamide (PA)-based resins, etc. In the case of PC-based resins, it is more preferable to use aromatic PCs made from bisphenol A. From the viewpoint of ensuring visibility, the total light transmittance of the support is preferably 70% or more, more preferably 80% or more, and even more preferably 85% or more. Furthermore, when the optimal processing temperature of the optical laminate described below is low, it is preferable to use, for example, an aromatic PCC composition (fully alicyclic polyester composition) or a PA-based resin having a glass transition temperature of 130°C or less.

[0053] Compared with PC resins, PA resins have less optical anisotropy, suppressed birefringence, and excellent solvent resistance. Furthermore, they are lightweight due to their low specific gravity, and their low heat distortion temperature allows for good processability during molding. Furthermore, PA resins are preferred because they prevent deterioration of appearance due to refractive index differences during injection molding and because it is desirable that the resin of the lens substrate layer and the support of the optical laminate be made of the same material to ensure adhesion. Furthermore, PA resins are preferred because they can suppress frame whitening due to outgassing caused by heating, eliminating restrictions on the frame material.

[0054] Examples of PA resins include nylons containing an aliphatic skeleton and aramids composed solely of an aromatic skeleton. Examples of nylons include nylon 6, nylon 11, nylon 12, and nylon 66. Examples of aramids include para-aramid and meta-aramid. In particular, the PA resin is preferably in the form of a transparent film or sheet; for example, a commercially available nylon film (film thickness 80 μm) manufactured by EMS can be used. The film thickness of the support is preferably 10 μm or more and 200 μm or less, and more preferably 40 μm or more and 100 μm or less.

[0055] (Adhesive Layer) The adhesive layer is used to bond the support and polarizing element, the support and light-reflecting layer, and the polarizing element and light-reflecting layer. The adhesive layer can be formed from a resin material containing at least a base polymer (hereinafter also referred to as the main agent) and a curing aid such as a crosslinking agent. Depending on the dilution component of the adhesive, it may be water-based, solvent-based, or solventless, and can be appropriately selected depending on the surface properties of the adherend and the curing method. From the viewpoint of compatibility with the hue-adjusting dye described below, the adhesive layer is preferably a solvent-based or solvent-free adhesive layer. The use of a solvent-based adhesive layer is particularly preferred due to the ease of preparing the dye solution and adjusting the dye concentration and transmittance in the system. Hereinafter, a solvent-based or solvent-free adhesive layer will be referred to as a "solvent-based or solvent-free adhesive layer," and a water-based adhesive layer will be referred to as an "aqueous adhesive layer."

[0056] Furthermore, from the viewpoint of improving the efficiency of lamination of each component and making it easier to determine a composition that ensures adhesion between layers, a radical polymerization type and / or cationic polymerization type ultraviolet-curing adhesive may be used. Among such ultraviolet-curing adhesives, a solventless ultraviolet-curing adhesive can be preferably used.

[0057] The adhesive layer is used to adhere between the support and the polarizing element, between the support and the light-reflecting layer, between the polarizing element and the light-reflecting layer, or between the support and another support, and may have at least one layer in the optical laminate, or may have multiple layers depending on the design of the optical laminate. Furthermore, when a TAC-based resin film is used as the support of the optical laminate, a water-based adhesive layer may be used to laminate the polarizing element or the TAC-based resin films together, or a water-based adhesive layer may be used in combination with a solvent-based or solventless adhesive layer. Furthermore, when laminating cholesteric liquid crystal layers contained in the light-reflecting layer together, a UV-curable adhesive may be used.

[0058] In order to improve adhesion, the surfaces of the components of the optical laminate may be subjected to surface modification using a commercially available treatment device such as corona treatment or plasma treatment during or before the bonding process of the components.

[0059] For the solvent-based or solventless adhesive layer, a transparent photocurable resin or thermosetting resin can be preferably used as the main component, such as an acrylic resin, a urethane resin, an epoxy resin, a silicone resin, a rubber resin, a polyvinyl ether resin, or a polyester resin. In particular, the processing of a polarized lens using an optical laminate and a lens substrate involves, as described below, a shaping process involving heat or integral molding with the resin. Therefore, from the viewpoint of these moldability, it is preferable that the adhesive layer contains a thermosetting resin, and among these, it is particularly preferable that it contains an amorphous polyester resin.

[0060] The amorphous polyester resin is soluble in organic solvents, preferably has a mass average molecular weight (Mw) of 15,000 or more and 30,000 or less, and more preferably has a glass transition temperature of -20°C or more and 20°C or less. These properties ensure excellent lens processability and adhesion between components, and also allow for easy formation of an adhesive layer by the coating method described below. Commercially available amorphous polyester resins include, for example, the "Vylon" series (product numbers: 200, 240, 245, 500, etc.) manufactured by Toyobo Co., Ltd.

[0061] The adhesive composition containing the amorphous polyester resin may contain a curing agent together with a diluting solvent. The type of curing agent is not particularly limited, but an isocyanate compound is preferred. A curing aid (also called a curing catalyst) may also be included to promote curing and control physical properties. The diluting solvent is not particularly limited as long as it can dissolve the amorphous polyester resin and various additives, but examples include methyl ethyl ketone (MEK), cyclopentanone (CPN), and cyclohexanone (CHN).

[0062] The viscosity of the adhesive composition is preferably in the range of 300 mPa·s to 600 mPa·s, and more preferably in the range of 300 mPa·s to 400 mPa·s.

[0063] (Hue-Adjusting Dye) The hue-adjusting dye has a maximum absorption wavelength (also referred to as λmax) in the visible light region and is used to adjust the reflected hue, reflectance in the visible light region, transmitted hue, and transmittance in the visible light region of the optical laminate. The hue-adjusting dye can be contained in the adhesive layer, and one or more types may be blended into the adhesive layer depending on the optical design. Furthermore, the hue-adjusting dye is preferably a dye that does not interact with the specific wavelength absorbing dye described below, such as by decomposition or aggregation, and is compatible or dispersible with the resin component of the adhesive layer. These materials can be generally referred to as "dyes for resin coloring." An optical laminate containing a hue-adjusting dye causes a decrease in transmittance within a specific wavelength range in the visible light region or overall transmittance based on the polarizing element.

[0064] The hue-adjusting dye may be contained in a first adhesive layer disposed between the first support and the light-reflecting layer in the optical laminate. By containing a hue-adjusting dye in the first adhesive layer between the first support and the light-reflecting layer, the reflected hue and reflectance of the optical laminate can be adjusted. Furthermore, the hue-adjusting dye contained in the first adhesive layer between the first support and the light-reflecting layer may contain two or more dyes having different maximum absorption wavelengths in any ratio. This allows the production of optical laminates exhibiting a variety of reflected hues, thereby providing optical laminates with excellent design.

[0065] The hue-adjusting dye may also be contained in the second adhesive layer disposed between the second support and the polarizing element. By including a hue-adjusting dye in the second adhesive layer between the second support and the polarizing element, the transmitted hue and transmittance of the optical laminate can be adjusted. In this case, since the dye-adjusting dye is included in the adhesive layer closer to the viewer than the light-reflecting layer with respect to incident external light, the reflected color and reflectance are not affected. As a result, it is possible to adjust only the transmitted hue and transmittance without impairing the design. Furthermore, the hue-adjusting dye contained in the second adhesive layer between the second support and the polarizing element may contain two or more dyes with different maximum absorption wavelengths in any ratio. This allows the design of a transmitted hue that provides a natural color scheme when viewed by the wearer as eyewear. Examples of natural color schemes include neutral grays and browns, and yellows that the wearer perceives as bright.

[0066] Examples of hue-adjusting dyes include Solvent Yellow 33, Disperse Yellow 54, Disperse Yellow 160, Disperse Yellow 201, Solvent Orange 60, Solvent Red 111, Solvent Red 135, Solvent Red 168, Solvent Red 207, Disperse Red 22, Solvent Red 52, Solvent Red 179, Disperse Red 60, Disperse Violet 31, Solvent Blue 36, and Solvent Violet Examples of suitable hue-adjusting dyes include Solvent Blue 13, Disperse Blue 14, Solvent Blue 94, Solvent Blue 63, Solvent Blue 104, Solvent Blue 97, Solvent Green 20, Solvent Violet 13, Disperse Violet 28, and Solvent Violet 36. These hue-adjusting dyes are resin coloring dyes and have good compatibility with amorphous polyester resins. Furthermore, resin coloring dyes have excellent color development properties in resins, so the amount required for hue adjustment can be reduced. As a result, the adhesive strength of the adhesive layer formed is not affected even when a resin coloring dye is incorporated, and sufficient adhesion strength can be maintained for the formation of an optical laminate.

[0067] The hue-adjusting dye preferably has heat resistance, particularly heat resistance that prevents the hue-adjusting dye from being decomposed or discolored by heat due to the thermal history caused by bending of the optical laminate or lens molding, which will be described later.

[0068] The optical properties of the optical laminate are adjusted using a hue-adjusting dye by incorporating multiple dyes corresponding to each wavelength range in the visible light range, such as those listed below (A) to (D), into the adhesive layer, based on the transmittance waveform of the polarizing element. This reduces the transmittance in the wavelength range corresponding to the maximum absorption wavelength (λmax) of each dye, adjusting the transmittance waveform across the visible light range and enabling the design of any desired color tone. Furthermore, the hue-adjusting dye is not limited to the dyes listed (A) to (D), and dyes exhibiting other colors of the same kind or dyes having multiple light absorption wavelength ranges may also be used as long as they satisfy the objectives of the present invention.

[0069] Representative examples of hue-adjusting dyes are as follows: (A) a red dye having a maximum absorption wavelength in the wavelength range of 400 nm or more and 500 nm or less, (B) a green dye having a maximum absorption wavelength in the wavelength range of 500 nm or more and 600 nm or less, (C) a blue dye having a maximum absorption wavelength in the wavelength range of 600 nm or more and 700 nm or less, and (D) a yellow dye having a maximum absorption wavelength in the wavelength range of 400 nm or more and 450 nm or less.

[0070] One of the hue-adjusting dyes preferably has an anthraquinone skeleton, and in the case of (A) a red dye, it is Solvent Red 168 represented by the chemical formula (1) below, (B) a green dye, it is Solvent Green 20 represented by the chemical formula (2) below, and (C) a blue dye, it is Solvent Blue 97 represented by the chemical formula (3) below. The other of the hue-adjusting dyes preferably has a yellow dye, and (D) Disperse Yellow 201 having a styryl skeleton represented by the chemical formula (4) below can be particularly preferably used. The amount of the hue-adjusting dye to be blended is, for example, preferably 0.001 parts by mass or more and 0.5 parts by mass or less, and more preferably 0.002 parts by mass or more and 0.4 parts by mass or less, per 100 parts by mass of the adhesive, which is the main agent contained in the adhesive composition.

[0071]

[0072]

[0073]

[0074]

[0075] As commercially available hue-adjusting dyes, for example, Plast Red 8320 from the Plast Blue series manufactured by Arimoto Chemical Industry Co., Ltd. can be used for Solvent Red 168, Plast Green 8645 from the same manufacturer can be used for Solvent Green 20, Plast Blue 8590 from the same manufacturer can be used for Solvent Blue 97, and Plast Yellow 8070 from the same manufacturer can be used for Disperse Yellow 201.

[0076] (Specific Wavelength Absorbing Dye) The optical laminate of the present invention may further contain a specific wavelength absorbing dye. The specific wavelength absorbing dye is used, particularly in eyewear, to absorb light in a specific wavelength range in the visible light region from incident light (external light) in order to increase the contrast of the field of view and impart effects such as anti-glare properties.

[0077] The specific wavelength absorbing dye may be contained in the first adhesive layer disposed between the first support and the light-reflecting layer for the purpose of adjusting the reflected hue and reflectance. This allows for color designs that cannot be reproduced with ordinary hue-adjusting dyes. Furthermore, even if the specific wavelength absorbing dye is contained in the first adhesive layer between the first support and the light-reflecting layer, the optical laminate absorbs light in a specific wavelength range in the visible light range, thereby enhancing the visual contrast and providing anti-glare properties as in the conventional case. Furthermore, the specific wavelength absorbing dye may be blended in combination with a hue-adjusting dye. This allows for a wider variety of color designs.

[0078] The specific wavelength absorbing dye may be contained in the second adhesive layer disposed between the second support and the polarizing element for the purpose of adjusting the transmission hue and transmittance. This allows the transmission hue of the optical laminate to be adjusted to a natural color scheme, thereby improving the visibility of the wearer. It is also possible to impart effects such as increasing the contrast of the field of view, which are conventional effects, and anti-glare properties.

[0079] The specific wavelength absorbing dye preferably has heat resistance, particularly heat resistance that prevents the specific wavelength absorbing dye from being decomposed or discolored by heat due to the thermal history caused by bending of the optical laminate or lens molding process described below.

[0080] The specific wavelength absorbing dye can be contained in the adhesive layer, and one or more types may be contained in the adhesive layer depending on the optical design. The optical characteristics of the specific wavelength absorbing dye are that it has a maximum absorption wavelength (λmax) in the wavelength range of 570 nm to 600 nm or 400 nm to 450 nm, and its half-width is preferably in the range of about 10 nm to 60 nm. Such specific wavelength absorbing dyes can be selected from, for example, cyanine-based, merocyanine-based, squarylium-based, xanthene-based, oxonol-based, azo-based, tetraazaporphyrin-based, polymethine-based dyes, etc., and in particular, tetraazaporphyrin-based dyes that exhibit a blue to purple color and are represented by the chemical formula (5) below can be preferably used.

[0081]

[0082] In formula (5), R １ ~R ８ each independently represents a hydrogen atom, a halogen atom, a nitro group, a cyano group, a hydroxy group, an amino group, a carboxy group, a sulfonic acid group, a linear, branched, or cyclic alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an aryloxy group having 6 to 20 carbon atoms, a monoalkylamino group having 1 to 20 carbon atoms, a dialkylamino group having 2 to 20 carbon atoms, a dialkylamino group having 7 to 20 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, a heteroaryl group, an alkylthio group having 6 to 20 carbon atoms, or an arylthio group having 6 to 20 carbon atoms, or may form a ring other than an aromatic ring via a linking group. M represents two hydrogen atoms, a divalent metal atom, a divalent mono-substituted metal atom, a tetravalent di-substituted metal atom, or an oxymetal atom.

[0083] Furthermore, the tetraazaporphyrin dye is represented by the formula (5), where M is Cu (divalent), and R １ ~R ８ is R in formula (5). １ and R ２, R ３ and R ４ , R ５ and R ６ and R ７ and R ８ a tet-butyl group (t-C ４ H ９ Preferably, the substituted aryl group is a positional isomer.

[0084] Commercially available tetraazaporphyrin dyes include, for example, FDG-005 and FDG-006 (both manufactured by Yamada Chemical Co., Ltd.). The maximum absorption wavelength (λmax) of the tetraazaporphyrin dye in the resin is 585 nm for FD-G005 and 595 nm for FDG-006. The specific wavelength absorbing dye can be incorporated into the adhesive layer so that the transmittance at the maximum absorption wavelength (λmax) in the adhesive layer is 5 to 70%, preferably 30 to 60%, thereby imparting excellent anti-glare effects to eyewear. Specifically, the amount of the specific wavelength absorbing dye incorporated is preferably 0.01 to 0.20 parts by mass, and more preferably 0.05 to 0.15 parts by mass, per 100 parts by mass of the adhesive layer, which is the main component contained in the adhesive composition.

[0085] (Polarized Lens) The polarized lens of the present invention can be obtained by using the optical laminate of the present invention and molding it into a desired shape with the light-reflecting layer facing outward. Furthermore, by fixing the polarized lens to a frame, eyewear of the present invention, such as sunglasses, goggles, and helmet visors, can be obtained. An example of the process for forming the polarized lens of the present invention is shown below, but the process is not limited to this.

[0086] For example, a polarized lens can be manufactured by punching the above-described optical laminate into a desired shape and then bending it. There are no particular restrictions on the bending method, and it is sufficient to process it through a step that can impart a spherical or aspherical shape depending on the purpose.

[0087] Specifically, the optical laminate described above is subjected to a shaping process in advance using a heat press or the like to facilitate processing into a lens shape when combined with a lens substrate (described later). A mold designed to a predetermined size is generally used for the shaping process, and is appropriately designed according to the design of the eyewear product. The optical laminate can be curved by placing the optical laminate in a bending mold (concave mold) and pressing it with a hemispherical mold (convex mold, also called a hot iron ball) heated to a predetermined temperature.

[0088] The bending conditions are, for example, in consideration of the bendability and heat resistance (discoloration of the polarizing element, etc.) of the optical laminate, and are performed at a temperature of 70 to 120°C, preferably 80 to 100°C, for a time period of 1 to 3 minutes. At this time, only a portion of the optical laminate to be used in the subsequent insert molding step may be simultaneously or sequentially trimmed from the sheet-like optical laminate.

[0089] The bent product may further have a resin (also called a lens substrate) injected into it. This has the advantage of making uneven thickness of the optical laminate invisible, and resin injection is used for lenses that do not have focal refractive power, but are particularly excellent in impact resistance, appearance, and eye fatigue. The material of the injected resin is preferably the same as the material of the layer that the injected resin comes into contact with, in order to prevent deterioration of appearance due to refractive index differences.

[0090] A resin material is used for the lens substrate so that the optical laminate of the present invention and a resin can be integrated and processed into a lens shape. The integration process can generally be performed using an insert molding method. The resin material is not particularly limited, and examples thereof include thermoplastic resins that can be molded by injection molding, and thermosetting resins that can be molded by distillation polymerization or the like and are generally used for eyewear lenses. Specific examples include (meth)acrylic resins such as methyl methacrylate homopolymers and copolymers of methyl methacrylate and one or more other monomers; diethylene glycol bisallyl carbonate resins such as diethylene glycol bisallyl carbonate homopolymers and copolymers of diethylene glycol bisallyl carbonate and one or more other monomers; acrylonitrile-styrene copolymers, halogen-containing copolymers; polysulfide resins such as homopolymers of monomers having sulfide bonds and copolymers of monomers having sulfide bonds and one or more other monomers; polyurea resins, PA resins, PC resins, polystyrene resins, polyolefin resins, polyvinyl chloride resins, polyester resins, PET resins, polyurethane resins, and sulfur-containing urethane resins such as polythiourethane resins; and epoxy resins. From the viewpoint of adhesion to the optical laminate, it is preferable that the lens substrate be formed from the same material as the layer to be in contact with it. As a specific example, the support of the optical laminate on the side to be integrally processed is made of a PA resin, and the lens substrate is also made of a PA resin, thereby enabling fusion bonding of the support and the lens substrate. This makes it possible to obtain a lens in which the optical laminate and the lens substrate are integrated.

[0091] (Evaluation of properties of optical laminate) A method for evaluating the properties exhibited by the optical laminate of the present invention will be described. The properties (reflection properties and transmission properties) of the optical laminate can be measured using, for example, a spectrophotometer ("UH4150" manufactured by Hitachi High-Tech Science Corporation). The evaluation of the optical properties may also be carried out in the form of a polarized lens, as long as it does not interfere with the measurement.

[0092] (Reflection measurement of light-reflecting layer and optical laminate) The reflectance of the light-reflecting layer and the optical laminate can be measured in accordance with JIS Z8722:2009, for example, using a spectrophotometer (Hitachi High-Tech Science Corporation, "UH4150"). Reflectance measurement is performed by total reflection measurement, in which the surface of the light-reflecting layer is placed in the integrating sphere of the spectrophotometer. At that time, natural light is used as the light source, and the reflectance is measured by placing the measurement sample at 0 degrees and 90 degrees, respectively, and the average value of the reflectance is taken as the reflectance. In addition, the detection condition for the reflectance at each wavelength is set to a pitch of 10 nm or less, preferably 5 nm or less, which can improve the accuracy of calculating the transmittance difference and reduce the difference from visual evaluation.

[0093] The average reflectance of the light-reflecting layer in the wavelength range of 500 nm to 700 nm (hereinafter referred to as "average reflectance (R1)") is preferably in the range of 10% to 30%, more preferably 15% to 25%. The average reflectance of the optical laminate in the wavelength range of more than 700 nm to 900 nm (hereinafter referred to as "average reflectance (R2)") is preferably in the range of 15% to 30%, more preferably 20% to 30%.

[0094] The angular dependence of the reflection hue of the light-reflecting layer and the optical laminate can be quantitatively evaluated using, for example, a motorized goniometer (DMS series) manufactured by Konica Minolta. Specifically, the measurement is performed in reflection mode, and as shown in FIG. 4, the light reflected from the reflection surface of a sample 33 placed flat on a measurement stage 30 can be measured by the light-receiving unit of the measurement device. In this case, the light-receiving unit can be tilted at any angle (0 to 70 degrees) relative to the sample surface. Here, a tilt angle of 0 degrees is defined as the perpendicular direction to the sample surface. The measurement stage 30 can also be rotated horizontally to any orientation (0 to 359 degrees, where 0 degrees is the initial installation position of the sample 33). FIG. 4 shows the light-receiving unit 31 of the measurement device installed at a tilt angle of 0 degrees and the light-receiving unit 32 of the measurement device when tilted at an angle θ, with the tilt direction of the light-receiving unit 32 being 0 degrees or 180 degrees relative to the measurement stage 30. The reflectance value obtained by this measurement can be obtained as a wavelength dependency, and therefore, optical characteristics (mainly luminosity-corrected reflectance Yr), CIE1976 (JIS Z8781-4) color space (L ＊ a ＊ b ＊ ) can be used to determine the hue value.

[0095] Measurement of the angle dependence of reflected hue generally takes into account the aspect of a polarized lens or eyewear having a curved shape, and therefore evaluates the hue change when the tilt angle is 10 degrees or more, preferably 30 degrees or more. For example, if the hue change is small at larger tilt angles, this is useful for application to polarized lenses or eyewear with a large curve diameter.

[0096] The evaluation of the hue change of the light-reflecting layer was performed using the following formula: ＊ a ＊ b ＊ Hue value a based on color space ＊ r and b ＊ In r, for example, the hue difference of each tilt angle relative to a tilt angle of 0 degrees is expressed as |Δa ＊ r | and |△b ＊ r| can be expressed as |△a ＊ r | and |△b ＊Each of |r| is preferably 5.0 or less, more preferably 4.0 or less, and particularly preferably 3.0 or less. ＊ r | and |△b ＊ Both r| are preferably 5.0 or less, more preferably 4.0 or less, and particularly preferably 3.0 or less. When the hue difference of the light-reflecting layer is within these ranges, almost no change in color is visible in visual evaluation.

[0097] The evaluation of the hue change of the optical laminate was also carried out by L ＊ a ＊ b ＊ Hue value a based on color space ＊ r and b ＊ In r, for example, the hue difference of each tilt angle relative to a tilt angle of 0 degrees is expressed as |Δa ＊ r | and |△b ＊ r| can be expressed as |△a ＊ is preferably 5.0 or less, more preferably 4.1 or less, and particularly preferably 3.0 or less. ＊ is preferably 7.0 or less, more preferably 5.0 or less, and particularly preferably 3.0 or less. By setting the hue difference of the optical laminate within these ranges, almost no change in color is visible in visual evaluation.

[0098] In the optical laminate of the present invention, it is particularly preferable that the amount of change in reflected hue when the observation position is tilted to 60 degrees from a direction perpendicular to the reflection surface as 0 degrees is |Δa ＊ r|≦5.0, and |Δb ＊ It is preferable to satisfy r|≦5.0.

[0099] The transmitted hue of the optical laminate is L ＊ a ＊ b ＊ Hue value a based on color space (CIE 1976) ＊ s and b ＊ In s, a ＊ s = -5.0 or more and 5.0 or less (including 0), and b ＊It is preferable that s is -5.0 or more and 5.0 or less (including 0), and a ＊ s = -3.0 or more and 3.0 or less, and b ＊ It is more preferable that s = -3.0 or more and 3.0 or less is satisfied. When the optical laminate exhibits a grayish hue, the visibility of the wearer is improved when the optical laminate is applied to eyewear.

[0100] (Method for manufacturing optical laminate) The method for manufacturing the optical laminate of the present invention includes a step of forming a polarizing element, a step of forming a light-reflecting layer, a step of forming an adhesive layer, and a step of laminating the support, the polarizing element, and the light-reflecting layer using each adhesive layer, and may be performed continuously in order starting from the step of forming the polarizing element, or each step may be performed sequentially.

[0101] From the viewpoints of ease of manufacturing and quality stability, the process of forming the adhesive layer preferably includes a step of dissolving various dyes in a solvent and then mixing the resulting solution with the main component of the adhesive layer. Specifically, the dyes are dissolved in a solvent using the same solvent as the dilution solvent used for the main component, and the resulting dye solution is blended into the main component or a solution of the main component. This allows the dyes to be uniformly mixed into the main component. Note that "dissolved" also means a uniformly dispersed state.

[0102] Furthermore, various dyes may be prepared as dye solutions using the same dilution solvent, and each dye solution may be mixed simultaneously or sequentially into the main agent or the main agent solution, or all dyes may be mixed together using the same dilution solvent to prepare dye solutions, which may then be mixed into the main agent or the main agent solution.

[0103] (Eyewear) The eyewear of the present invention comprises the above-mentioned polarized lens. A hard coat, an anti-reflection film, etc. is appropriately formed on the surface of the polarized lens, and the polarized lens is then fixed to a frame by edging, drilling, screwing, etc., to obtain the eyewear of the present invention.

[0104] The eyewear may contain the above-mentioned ultraviolet absorber in any layer of the optical laminate or lens substrate to provide ultraviolet absorption function, or may contain a dye, metal oxide, or the like to provide infrared absorption function, or may have a further layer laminated thereon containing these. The eyewear may also contain a photochromic material in any layer of the optical laminate or lens substrate to provide photochromic function, or may have a further layer laminated thereon containing this.

[0105] The eyewear of the present invention can be worn both indoors and outdoors as highly fashionable eyewear. In such cases, a higher transmittance than that of ordinary lenses is required, and the eyewear is designed to satisfy "Lens Category 1" (luminous transmittance (τv): 43% < τv ≦ 80%) specified in the European standard for lens transmittance (EN ISO12312-1:2013 / Al:2015).

[0106] The European standard (EN ISO12312-1:2013 / Al:2015) is a standard for personal protective equipment such as sunglasses, and corresponds to the personal protective equipment regulations established in the European region. In this standard, the explanation label for general-use sunglasses lenses and the outline of the luminous transmittance (τv) and lens classification requirements are as follows. Here, τv corresponds to the above-mentioned Ys. Explanation label: Light-tinted sunglasses Lens category 0: τv > 80% Lens category 1: 43% < τv ≦ 80% Explanation label: General-use sunglasses Lens category 2: 18% < τv ≦ 43% Lens category 3: 8% < τv ≦ 18% Explanation label: Special-use sunglasses Lens category 4: 3% < τv ≦ 8%

[0107] Based on the above embodiments, the present invention relates to the following [1] to

[10] : [1] An optical laminate comprising: a light-reflecting layer including at least one cholesteric liquid crystal layer in which the absolute value of the difference (|ΔR1-R2|) between the average reflectance (R1) in a wavelength range of 500 nm or more and 700 nm or less and the average reflectance (R2) in a wavelength range of more than 700 nm and 900 nm or less is 10.0 or less, a polarizing element including at least one dichroic dye, and a first support and a second support sandwiching the light-reflecting layer and the polarizing element, wherein the first support, the light-reflecting layer, the polarizing element, and the second support are laminated in this order, a first adhesive layer is disposed between the light-reflecting layer and the first support, and a second adhesive layer is disposed between the polarizing element and the second support, and the first adhesive layer contains at least one of a hue-adjusting dye and a specific wavelength-absorbing dye. [2] When the observation position is inclined 60 degrees from the reflection surface, the direction perpendicular to the reflection surface of the optical laminate is set to 0 degrees, L ＊ a ＊ b ＊ Hue value a based on color space (CIE 1976) ＊ r and b ＊ In r, the change in the reflected hue of the optical laminate is |Δa ＊ r|≦5.0 and |Δb ＊ [3] L ＊ a ＊ b ＊ Hue value a based on color space (CIE 1976) ＊ s and b ＊ In s, the transmission hue of the optical laminate is ＊ s = -5.0 or more and 5.0 or less, and b ＊The optical laminate according to any one of [1] to [2] above, wherein s=-5.0 or more and 5.0 or less is satisfied. [4] The optical laminate according to any one of [1] to [3] above, wherein the polarizing element has a luminosity-corrected single transmittance of 25% or more and 45% or less, and a luminosity-corrected polarization degree of 90% or more. [5] The optical laminate according to any one of [1] to [4] above, wherein the light-reflecting layer comprises at least one cholesteric liquid crystal layer (R-form) having a right-handed helical direction and at least one cholesteric liquid crystal layer (L-form) having a left-handed helical direction. [6] The optical laminate according to any one of [1] to [5] above, wherein the hue-adjusting dye is a dye for resin coloring and contains at least one dye selected from the group consisting of: (A) a reddish dye having a maximum absorption wavelength in a wavelength range of 400 nm to 500 nm, (B) a greenish dye having a maximum absorption wavelength in a wavelength range of 500 nm to 600 nm, (C) a blueish dye having a maximum absorption wavelength in a wavelength range of 600 nm to 700 nm, and (D) a yellowish dye having a maximum absorption wavelength in a wavelength range of 400 nm to 450 nm. [7] The optical laminate according to any one of [1] to [6] above, wherein the first adhesive layer and the second adhesive layer contain an amorphous polyester resin. [8] The optical laminate according to any one of [1] to [7] above, wherein the second adhesive layer contains at least one of the hue-adjusting dyes. [9] A polarized lens comprising a lens substrate and the optical laminate according to any one of [1] to [8] above.

[10] Eyewear comprising the polarized lens according to [9] above.

[0108] The present invention will be described in detail below with reference to examples, but the present invention is not limited to such examples. In the examples, "parts" means parts by mass.

[0109] (A) Preparation of Polarizing Element NYSH-30 (manufactured by Nippon Kayaku Co., Ltd.), a dye-based PVA resin film for polarized sunglasses, was used as the polarizing element. The polarization characteristics of the polarizing element were measured using a spectrophotometer (manufactured by Hitachi High-Tech Science Corporation, "U-4100"), and the luminosity-corrected single transmittance (Ys) was 38.0% and the luminosity-corrected polarization degree (Py) was 99.50%. ＊a ＊ b ＊ The hue in the color space is a ＊ s = -1.1, b ＊ The value of s was 5.3, and the color was grayish.

[0110] (B) Preparation of Cholesteric Liquid Crystal Layers The cholesteric liquid crystal layers were prepared according to Example 1 of JP 2003-139953 A. A right-handed helical cholesteric liquid crystal layer (sample name: R-Wide Band Silver (hereinafter also referred to as "R-WSi")) having a substantially uniform reflectance over the wavelength range of 380 nm to 900 nm, and a left-handed helical cholesteric liquid crystal layer (sample name: L-Wide Band Silver (hereinafter also referred to as "L-WSi")) having a substantially uniform reflectance over the wavelength range of 380 nm to 900 nm, were prepared on a rubbed PET film (manufactured by Toyobo Co., Ltd., "A4100", film thickness: 50 μm) as a substrate. Furthermore, two cholesteric liquid crystal layers (sample name L-WSi / R-WSi (hereinafter also referred to as "L-WSi / R-WSi")) were prepared by laminating the R-WSi and L-WSi layers obtained from the cholesteric liquid crystal layers. Similarly, following the description of Example 1 in JP-A 2003-139953, cholesteric liquid crystal layers (sample names R550 and R650 (hereinafter also referred to as "R550" and "R650", respectively)) having right-handed helical alignment with maximum reflection lengths of 550 and 650 nm, and cholesteric liquid crystal layers (sample names L620 and L650 (hereinafter also referred to as "L620" and "L650", respectively)) having left-handed helical alignment with maximum reflection lengths of 620 and 650 nm were prepared on a rubbed PET film (manufactured by Toyobo Co., Ltd., "A4100", film thickness 50 μm) as a substrate. Each of these cholesteric liquid crystal layers had a thickness of about 4 μm.

[0111] Each prepared cholesteric liquid crystal layer was placed flat with the reflective surface facing up, and the color was observed when viewed from directly above (front). The reflectance of the cholesteric liquid crystal in the wavelength range of 380 nm to 900 nm was measured using a spectrophotometer (Hitachi High-Tech Science Corporation, "U-4100") with a detection condition of 1 nm pitch. From the obtained measurement data, the absolute value of the difference between the average reflectance (R1) in the wavelength range of 500 nm to 700 nm and the average reflectance (R2) in the wavelength range of more than 700 nm to 900 nm (|ΔR1-R2|) was calculated. Table 1 shows the measurement results for each cholesteric liquid crystal layer. Figure 5 shows the reflectance spectra of L-WSi / R-WSi, R550, and R650 in the wavelength range of 380 nm to 900 nm.

[0112]

[0113] In Table 1, both the fabricated cholesteric liquid crystal layers R-WSi and L-WSi exhibited a silvery reflection hue, and the average reflectances of L-WSi containing the L-form of the cholesteric liquid crystal and R-WSi containing the R-form of the cholesteric liquid crystal were 17.7% and 17.1%, respectively. The absolute value differences (|ΔR1-R2|) between the average reflectances (R1) and (R2) were 2.8 and 2.0, respectively, indicating flat reflectance up to a long wavelength region of 900 nm. The two-layer structure fabricated by stacking the fabricated R-WSi and L-WSi also exhibited a silvery reflection hue, with an average reflectance of 30.2% and an absolute value difference (|ΔR1-R2|) of 3.5.

[0114] The cholesteric liquid crystal layer R550 exhibited a green reflection hue when observed from the front. The difference (|ΔR1-R2|) between the absolute values ​​of the average reflectances (R1) and (R2) was 11.8, and a localized reflection waveform was observed near 550 nm. The cholesteric liquid crystal layers L620, R650, and L650 exhibited a red reflection hue when observed from the front. The difference (|ΔR1-R2|) between the absolute values ​​of the average reflectances (R1) and (R2) was 10.5, 10.6, and 12.1, respectively, and a localized reflection waveform was observed near 620 to 650 nm.

[0115] The evaluation of the angle dependency of the reflection hue of the obtained cholesteric liquid crystal layer was carried out using a motorized goniometer ("DMS505" manufactured by Konica Minolta), and the hue values ​​(a ＊ r, b ＊ The hue values ​​were measured when the stage of the device was rotated to 0 degrees, 45 degrees, and 90 degrees, but since there was no significant difference between the orientations, the hue values ​​were calculated as the average value. These evaluation results are shown in Table 2. Here, |Δa ＊ r | and |△b ＊ r| represents the hue difference between the reflection hue at an inclination angle of 0 degrees and the reflection hue at each inclination angle.

[0116]

[0117] In the vertical direction (0°) of the obtained cholesteric liquid crystal layer, L-WSi, R-WSi, and their laminated L-WSi / R-WSi all exhibited a neutral silver hue. Furthermore, even when the tilt angle of the light receiving part of the measuring device was changed (10 degrees, 30 degrees, and 60 degrees), the change in hue was small, and |Δa ＊ r| and |Δb ＊ The change in r| was 5.0 or less in all cases.

[0118] In the vertical direction (0°) of the obtained cholesteric liquid crystal layer, R550 exhibited a yellow-green hue. However, when the inclination angle (10°, 30°, and 60°) of the light receiving part of the measurement device was changed, the inclination angle of |Δa ＊ r| and |Δb ＊ The amount of change in |Δa ＊ r| and |Δb ＊ The change in |Δa| was very large, reaching 45.1 and 77.3, respectively. The visually observed reflected color was blue. Similarly, for L620, R650, and L650, a red reflected hue was observed in the vertical direction (0°). However, when the inclination angle of the light receiving part of the measuring device was changed (10°, 30°, and 60°), the change in |Δa| ＊ r| and |Δb ＊The amount of change in |Δa ＊ The changes in r| were extremely large, reaching 75.8, 52.4, and 49.7, respectively. Furthermore, the reflected color was green when visually observed.

[0119] Next, the preparation of the optical laminates of Examples 1 to 7 and Comparative Examples 1 and 2 will be described.

[0120] [Example 1] (1) Preparation of Adhesive Composition 1 An organic solvent-soluble polyester resin (manufactured by Toyobo Co., Ltd., "Vylon 500", resin solids content 44.9% by mass) serving as the adhesive's main component was mixed with 2% by mass of an isocyanate-based curing agent (manufactured by Soken Chemical & Engineering Co., Ltd., "590E"), 0.01% by mass of dibutyltin dilaurate (DBSn), 0.13% by mass of Disperse Yellow 201 as a hue-adjusting dye, and 11% by mass of cyclohexanone as a dilution solvent to obtain Adhesive Composition 1. Here, the hue-adjusting dye was dissolved in a dilution solvent in advance, and then the solution was mixed with the main component to uniformly mix it into the main component. The viscosity of Adhesive Composition 1 was measured using a viscometer (manufactured by Toki Sangyo Co., Ltd., "TVB-10M") and was 350 mPa s. At this time, the adhesive composition 1 was formed into a film on a first support described later, and the optical property L ＊ a ＊ b ＊ The hue value in the color space is a ＊ = -10.3, b ＊ = 24.0.

[0121] (2) Preparation of Adhesive Composition 2 An organic solvent-soluble polyester resin (manufactured by Toyobo Co., Ltd., "Vylon 500", resin solids content 44.9% by mass) serving as the main adhesive agent was mixed with 2% by mass of an isocyanate-based curing agent (manufactured by Soken Chemical & Engineering Co., Ltd., "590E"), 0.01% by mass of dibutyltin dilaurate (DBSn), and 11% by mass of cyclohexanone as a dilution solvent to obtain Adhesive Composition 2. The viscosity of the obtained Adhesive Composition 2 was measured with a viscometer (manufactured by Toki Sangyo Co., Ltd., "TVB-10M") and was 350 mPa s. The obtained Adhesive Composition 2 was colorless and transparent.

[0122] (3) Preparation of the light-reflecting layer The first cholesteric liquid crystal layer was prepared in (B) above, and the second cholesteric liquid crystal layer was prepared in (B) above. The liquid crystal surfaces were laminated using the ultraviolet-curable adhesive described in Example 1 of WO 2019 / 116760. A light-reflecting layer having a configuration of R-WSi / L-WSi sandwiched between PET substrates was prepared. The obtained light-reflecting layer exhibited a silvery reflective color, and the average reflectance in the wavelength range of 380 nm to 900 nm was 30.2%.

[0123] (4) Preparation of optical laminate As a first support, one side of a TAC film (manufactured by Fujifilm Corporation, "TD-80UL", film thickness 80 μm) that had been saponified (immersed in a 2N aqueous sodium hydroxide solution at 40 ° C. for 10 minutes) was coated with the above-mentioned adhesive composition 1 by a die coater method, and the coated film was dried at 100 ° C. for 3 minutes to remove the solvent, forming an adhesive layer 1 (film thickness 18 μm) on the TAC film. Next, the PET substrate on the R-WSi side of the light-reflecting layer prepared in (3) was peeled off, and the R-WSi liquid crystal layer and adhesive layer 1 were bonded together to obtain a laminate having a laminate structure of first support / first adhesive layer / R-WSi / L-WSi / PET substrate. Thereafter, the PET substrate on the L-WSi side was peeled off, and the liquid crystal surface of the L-WSi and the polarizing element (NYSH-30) described in (A) above were laminated using the ultraviolet-curable adhesive described in Example 1 of WO 2019 / 116760, thereby producing a laminate arranged in the order of first support / first adhesive layer / R-WSi / L-WSi / polarizing element.

[0124] Next, the adhesive composition 2 described above was applied to one side of a PA resin film (manufactured by LOFO, "TRF-800", film thickness 80 μm) as a second support by a die coater method, and the coating film was dried at 100 ° C for 3 minutes to remove the solvent, forming an adhesive layer 2 (film thickness 18 μm) on the PA resin film. The polarizing element side of the laminate prepared above was then bonded to the adhesive layer 2 to prepare an optical laminate in the following order from the external light incident side: first support / first adhesive layer / R-WSi / L-WSi / polarizing film / second adhesive layer / second support. Furthermore, the prepared optical laminate was aged at 35 ° C for 1 week to promote the curing reaction of each adhesive layer and to promote adhesion between each support and the light-reflecting layer and polarizing element.

[0125] Example 2 (1) Preparation of Adhesive Composition 1 This is the same as the adhesive composition 1 described in Example 1 (1).

[0126] (2) Preparation of adhesive composition 2 The adhesive's main component is an organic solvent-soluble polyester resin (manufactured by Toyobo Co., Ltd., "Vylon 500", resin solids content 44.9% by mass), an isocyanate-based curing agent (manufactured by Soken Chemical & Engineering Co., Ltd., "590E") 2% by mass, dibutyltin dilaurate (DBSn) 0.01% by mass, a red-based dye Solvent Red 168 as a hue adjusting dye 0.17% by mass, a blue-based dye Solvent Blue 97 0.17% by mass, a specific wavelength absorbing dye FDG-005 (manufactured by Yamada Chemical Co., Ltd.) 0.21% by mass, and cyclohexanone as a dilution solvent were mixed at a ratio of 11% by mass to obtain adhesive composition 2. Here, the hue adjusting dye and the specific wavelength absorbing dye were dissolved in a dilution solvent in advance, and then the solution was mixed with the main component to uniformly mix the main component. The viscosity of the obtained adhesive composition 2 was measured with a viscometer ("TVB-10M" manufactured by Toki Sangyo Co., Ltd.) and was found to be 350 mPa·s. At this time, the adhesive composition 2 was formed into a film on a second support and used as a second adhesive layer, and the optical properties L ＊ a ＊ b ＊ The hue value in the color space is a ＊ = 9.4, b ＊ =-21.1.

[0127] (3) Preparation of Light Reflecting Layer The same as the light reflecting layer described in (3) of Example 1 was prepared.

[0128] (4) Preparation of optical laminate An optical laminate was prepared in the same manner as in (4) of Example 1, except that the adhesive composition 1 described in (1) of Example 1 was used as the first adhesive layer, the adhesive composition 2 described in (2) of Example 2 was used as the second adhesive layer, and the arrangement was, from the external light incident side, first support / first adhesive layer / R-WSi / L-WSi / polarizing element / second adhesive layer / second support.

[0129] [Example 3] (1) Preparation of Adhesive Composition 1 Adhesive composition 1 was prepared in the same manner as in (1) of Example 1, except that 0.51 mass % of Solvent Green 28 was mixed with the main adhesive agent as a hue-adjusting dye. At this time, the adhesive composition 1 was formed into a film on a first support, and the optical property L ＊ a ＊ b ＊ The hue value in the color space is a ＊ = -23.1, b ＊ = 1.2.

[0130] (2) Preparation of Adhesive Composition 2 Adhesive composition 2 was prepared in the same manner as in (1) of Example 1, except that 0.43% by mass of Solvent Red 168 was mixed with the main adhesive agent as a hue-adjusting dye. At this time, adhesive composition 2 was formed into a film on a second support, and the optical properties L ＊ a ＊ b ＊ The hue value in the color space is a ＊ = 19.4, b ＊ =-1.9.

[0131] (3) Preparation of Light Reflecting Layer The same as the light reflecting layer described in (3) of Example 1 was prepared.

[0132] (4) Preparation of Optical Laminate An optical laminate was prepared in the same manner as in (4) of Example 1, except that the adhesive composition 1 described in (1) of Example 3 was used as the first adhesive layer, the adhesive composition 2 described in (2) of Example 3 was used as the second adhesive layer, and the arrangement was, from the external light incident side, first support / first adhesive layer / R-WSi / L-WSi / polarizing film / second adhesive layer / second support.

[0133] [Example 4] (1) Preparation of Adhesive Composition 1 Adhesive composition 1 was prepared in the same manner as in (1) of Example 1, except that 0.24 mass % of FDG-005 was mixed as a specific wavelength absorbing dye in place of the hue adjusting dye into the main component of the adhesive. At this time, adhesive composition 1 was formed into a film on a first support, and the optical property L ＊ a ＊ b ＊ The hue value in the color space is a ＊ = 7.9, b ＊ =-19.6.

[0134] (2) Preparation of Adhesive Composition 2 Adhesive composition 2 was prepared in the same manner as in (1) of Example 1, except that 0.06 wt % of Disperse Yellow 201 was mixed with the main adhesive agent as a hue-adjusting dye. At this time, adhesive composition 2 was formed into a film on a second support, and the optical properties L ＊ a ＊ b ＊ The hue value in the color space is a ＊ = -5.4, b ＊ = 11.8.

[0135] (3) Preparation of Light Reflecting Layer The same as the light reflecting layer described in (3) of Example 1 was prepared.

[0136] (4) Preparation of Optical Laminate An optical laminate was prepared in the same manner as in (4) of Example 1, except that the adhesive composition 1 described in (1) of Example 4 was used as the first adhesive layer, the adhesive composition 2 described in (2) of Example 4 was used as the second adhesive layer, and the arrangement was, from the external light incident side, first support / first adhesive layer / R-WSi / L-WSi / polarizing film / second adhesive layer / second support.

[0137] [Example 5] (1) Preparation of adhesive composition 1 Adhesive composition 1 was prepared in the same manner as in (1) of Example 1, except that 0.51 mass % of Solvent Red 168 and 0.085 mass % of Disperse Yellow 201 were used as hue-adjusting dyes relative to the main adhesive agent. At this time, adhesive composition 1 was formed into a film on a first support, and the optical property L ＊ a ＊ b ＊ The hue value in the color space is a ＊ = 16.1, b ＊ = 14.4.

[0138] (2) Preparation of Adhesive Composition 2 Adhesive composition 2 was prepared in the same manner as in (1) of Example 1, except that 0.34% by mass of Solvent Blue 97 and 0.085% by mass of Solvent Green 28 were used in combination as hue-adjusting dyes relative to the main adhesive agent. At this time, adhesive composition 2 was formed into a film on a second support, and the optical properties L ＊ a ＊ b ＊ The hue value in the color space is a ＊ = -10.2, b ＊ =-14.3.

[0139] (3) Preparation of Light Reflecting Layer The same as the light reflecting layer described in (3) of Example 1 was used.

[0140] (4) Preparation of Optical Laminate An optical laminate was prepared in the same manner as in (4) of Example 1, except that the adhesive composition 1 described in (1) of Example 5 was used as the first adhesive layer, the adhesive composition 2 described in (2) of Example 5 was used as the second adhesive layer, and the arrangement was, from the external light incident side, first support / first adhesive layer / R-WSi / L-WSi / polarizing film / second adhesive layer / second support.

[0141] [Example 6] (1) Preparation of Adhesive Composition 1 Adhesive composition 1 was prepared in the same manner as in (1) of Example 1, except that 0.51 mass % of Solvent Red 168 was mixed with the main agent of the adhesive as a hue-adjusting dye. At this time, adhesive composition 1 was formed into a film on a first support, and the optical property L＊ a ＊ b ＊ The hue value in the color space is a ＊ = 22.9, b ＊ =-2.1.

[0142] (2) Preparation of Adhesive Composition 2 Adhesive composition 2 was prepared in the same manner as in (1) of Example 1, except that 0.085 mass% of Solvent Blue 97 and 0.34 mass% of Solvent Green 28 were used as hue-adjusting dyes relative to the main adhesive agent. At this time, adhesive composition 2 was formed into a film on a second support, and the optical properties L ＊ a ＊ b ＊ The hue value in the color space is a ＊ = -17.5, b ＊ =-2.9.

[0143] (3) Preparation of Light Reflecting Layer The same as the light reflecting layer described in (3) of Example 1 was prepared.

[0144] (4) Preparation of optical laminate An optical laminate was prepared in the same manner as in (4) of Example 1, except that the adhesive composition 1 described in (1) of Example 6 was used as the first adhesive layer, the adhesive composition 2 described in (2) of Example 6 was used as the second adhesive layer, and the arrangement was, from the external light incident side, first support / first adhesive layer / R-WSi / L-WSi / polarizing film / second adhesive layer / second support.

[0145] [Example 7] (1) Preparation of Adhesive Composition 1 Adhesive composition 1 was prepared in the same manner as in (1) of Example 1, except that 0.17% by mass of Solvent Blue 97 and 0.17% by mass of Solvent Green 28 were used as hue-adjusting dyes, and 0.13% by mass of FDG-005 was used as a specific wavelength absorbing dye, relative to the main component of the adhesive. At this time, adhesive composition 1 was formed into a film on a first support, and the optical property L ＊ a ＊ b ＊ The hue value in the color space is a ＊ = -10.4, b ＊ =-12.4.

[0146] (2) Preparation of Adhesive Composition 2 Adhesive composition 2 was prepared in the same manner as in (1) of Example 1, except that 0.26% by mass of Solvent Red 168 and 0.05% by mass of Disperse Yellow 201 were used in combination as hue-adjusting dyes relative to the main adhesive agent. At this time, adhesive composition 2 was formed into a film on a second support, and the optical properties L ＊ a ＊ b ＊ The hue value in the color space is a ＊ = 7.6, b ＊ =8.9.

[0147] (3) Preparation of Light Reflecting Layer The same as the light reflecting layer described in (3) of Example 1 was prepared.

[0148] (4) Preparation of Optical Laminate An optical laminate was prepared in the same manner as in (4) of Example 1, except that the adhesive composition 1 described in (1) of Example 7 was used to form the first adhesive layer, the adhesive composition 2 described in (2) of Example 7 was used to form the second adhesive layer, and the arrangement was, from the external light incident side, first support / first adhesive layer / R-WSi / L-WSi / polarizing film / second adhesive layer / second support.

[0149] Comparative Example 1 (1) Preparation of Adhesive Composition 1 This is the same as Adhesive Composition 2 described in Example 1 (2).

[0150] (2) Preparation of Adhesive Composition 2 This is the same as Adhesive Composition 2 described in Example 1 (2).

[0151] (3) Preparation of Light-Reflecting Layer Using the R550 prepared in (B) above as the first cholesteric liquid crystal layer and the L650 prepared in (B) above as the second cholesteric liquid crystal layer, the respective liquid crystal surfaces were laminated using the ultraviolet-curable adhesive described in Example 1 of WO 2019 / 116760. A light-reflecting layer having a configuration of R550 / L650 sandwiched between PET substrates was prepared. The obtained light-reflecting layer exhibited a golden reflective color, and the average reflectance in the wavelength range of 380 nm to 900 nm was 24.4%.

[0152] (4) Preparation of Optical Laminate An optical laminate was prepared in the same manner as in (4) of Example 1, except that the adhesive composition 1 described in (1) of Comparative Example 1 was used to form the first adhesive layer, the adhesive composition 2 described in (2) of Comparative Example 1 was used to form the second adhesive layer, and the arrangement was, from the external light incident side, first support / first adhesive layer / R550 / L650 / polarizing film / second adhesive layer / second support.

[0153] Comparative Example 2 (1) Preparation of Adhesive Composition 1 This is the same as Adhesive Composition 2 described in Example 1 (2).

[0154] (2) Preparation of Adhesive Composition 2 This is the same as Adhesive Composition 2 described in Example 1 (2).

[0155] (3) Preparation of Light-Reflecting Layer Using the R650 prepared in (B) above as the first cholesteric liquid crystal layer and the L620 prepared in (B) above as the second cholesteric liquid crystal layer, the respective liquid crystal surfaces were laminated using the ultraviolet-curable adhesive described in Example 1 of WO 2019 / 116760. A light-reflecting layer having a configuration of R650 / L620 sandwiched between PET substrates was prepared. The obtained light-reflecting layer exhibited a gold reflective color, and the average reflectance in the wavelength range of 380 nm to 900 nm was 24.4%.

[0156] (4) Preparation of Optical Laminate An optical laminate was prepared in the same manner as in (4) of Example 1, except that the adhesive composition 1 described in (1) of Comparative Example 2 was used as the first adhesive layer, the adhesive composition 2 described in (2) of Comparative Example 2 was used as the second adhesive layer, and the arrangement was, from the external light incident side, first support / first adhesive layer / R650 / L620 / polarizing film / second adhesive layer / second support.

[0157] Table 3 shows the configurations of the optical laminates produced in Examples 1 to 7 and Comparative Examples 1 and 2. However, descriptions of adhesive layers and their arrangements when an ultraviolet-curable adhesive is used in each configuration are omitted. In addition, in the optical laminates of Examples 1 to 7 and Comparative Examples 1 and 2, the hue values ​​a of the first adhesive layer and the second adhesive layer are ＊ and b ＊are shown in Table 3. Furthermore, Fig. 6 shows the reflection spectra of the optical laminates produced in Example 1 and Comparative Example 1 in the wavelength range of 380 nm to 900 nm.

[0158]

[0159] Next, evaluation of the optical properties of the optical laminates obtained in Examples 1 to 7 and Comparative Examples 1 and 2 will be described.

[0160] (C) Evaluation of Optical Properties of Optical Laminate As the reflection and transmission properties of the optical laminate, the transmission properties (Ys, L) in the visible light range were measured using a spectrophotometer (UH4150). ＊ s, a ＊ s, b ＊ s and Py) and reflection properties (Yr, L ＊ r, a ＊ r and b ＊ Furthermore, the reflection hue and transmission hue in the front direction of the optical laminate were measured by placing the optical laminate flat with the surface on the external light incident side facing upward in a room under fluorescent lighting and visually observing the optical laminate from a vertical direction, and the transmission hue was measured by visually observing the optical laminate in a room under fluorescent lighting. Table 4 shows these evaluation results.

[0161]

[0162] In Example 1, the color value a of adhesive composition 1 in Table 3 ＊ and b ＊ The values ​​of a were very similar to the reflection characteristics of the optical laminate in Table 4, and it was possible to adjust the desired reflection color. In addition, since no hue-adjusting dye that would be a complementary color was blended into adhesive composition 2, the transmission color of the optical laminate exhibited yellow, and the transmission characteristics were ＊ s is -9.3, b ＊ The color value a of adhesive composition 1 in Table 3 is 22.9. ＊ and b ＊ was very similar to the value of

[0163] In Examples 2 to 7, Ys is in the range of 15.2 to 19.7%, Py is in the range of 98.5 to 99.2%, and the transmittance is a ＊ s is -2.9 to 0.7, b ＊The hue value a of adhesive composition 1 in Table 3 was in the range of -1.4 to 3.4, and the adhesive composition exhibited optical properties suitable for an optical laminate for polarized sunglasses. ＊ and b ＊ The values ​​of were very similar to the reflection hues of the optical laminates in Table 4, and it was possible to adjust the desired reflection hue.

[0164] On the other hand, in Comparative Examples 1 and 2, different light-reflecting layers were used, and furthermore, no hue-adjusting dye was blended into Adhesive Composition 1, so the reflected color of each combination of light-reflecting layers was exhibited. Furthermore, since no hue-adjusting dye was blended into Adhesive Composition 2, coloring was observed in the transmitted color.

[0165] (Angle Dependence of Reflection Hue of Optical Laminate) The angle dependence of the reflection hue of the obtained optical laminate was evaluated using a motorized goniometer (manufactured by Konica Minolta, Inc., "DMS505"), and the hue values ​​(a ＊ r, b ＊ The hue values ​​were measured when the stage of the measuring device was rotated to 0 degrees, 45 degrees, and 90 degrees, but since there was no significant difference between the orientations, the hue values ​​were calculated as the average value. These evaluation results are shown in Table 5. In addition, |Δa ＊ r | and |△b ＊ The r| indicates the hue difference between each tilt angle and a tilt angle of 0 degree. Furthermore, Table 5 shows the appearance color observed when tilted at each angle.

[0166]

[0167] In Examples 1 to 7, even when the tilt angle of the light receiving part of the measuring device was changed (10 degrees, 30 degrees, and 60 degrees), the change in hue was small, and |Δa ＊ The change in r| is 3.0 or less, and |Δb ＊The change in r| was 7.0 or less. This is because the reflection band of the R-WSi / L-WSi used in the light-reflective layer is wide and uniform from the visible light region to the near-infrared region, and even when the reflection wavelength is shifted to shorter wavelengths by observation at an oblique angle, the near-infrared region with its uniform reflection band covers the reflectance of the visible light region, so there appears to be virtually no change in reflectance. Furthermore, the hue-adjusting dye contained in adhesive composition 1 does not change its absorption band even when observed at an oblique angle, so it was possible to produce an optical laminate with little color change and exhibiting any reflection color.

[0168] On the other hand, in Comparative Examples 1 and 2, when the inclination angle of the light receiving part of the measuring device is 10 degrees, |Δa ＊ r| and |Δb ＊ Although the change in |r| was very small, less than 1.0, at an inclination angle of 30 degrees, in Comparative Example 1, ＊ In Comparative Example 2, the change in |Δb ＊ At an inclination angle of 60 degrees, the change in |Δa ＊ r| and |Δb ＊ The change in |Δa ＊ r| and |Δb ＊ The change in r| exceeded 70.0 and 50.0, respectively, indicating a very large color change. This is because the reflection bands of R550, L620, R650, and L650 used in the light-reflecting layer are narrow, and when observed at an inclined angle, the reflection wavelength shifts to short wavelengths and does not have a reflection band on the long wavelength side, resulting in a large change in the reflection waveform in the visible light range.

[0169] (Shaping of optical laminate) The obtained optical laminate was subjected to shaping using a heat press. The optical laminate was placed in a bending mold (concave, 9 cmΦ), and a hemispherical hot iron ball heated to 100 ° C. was pressed for about 3 minutes to bend the reflective surface to the convex side. The degree of curvature of the obtained curved shape was measured with a curve meter (manufactured by Sannishimura Co., Ltd., model number 340) and was 8 curves.

[0170] (Visual evaluation of reflective hue of shaped product) The optical laminate subjected to the above-mentioned shaping process was placed flat with the light-reflecting layer facing up, and the color of the reflective layer when observed from directly above (front direction) and when observed from an oblique angle (about 45 to 60 degrees) was evaluated according to the following criteria. The results of the visual evaluation are shown in Table 6.

[0171] (Evaluation Criteria) ○: The same reflected color is seen as when the optical laminate is observed from a perpendicular direction. The scenery color observed through the laminate is naturally colored and appears grayish. ×: A different color is seen as when the optical laminate is observed from a perpendicular direction. The scenery color observed through the laminate is not grayish but appears colored.

[0172]

[0173] In Examples 1 to 7, the results were consistent with the results of observing the optical laminate at an inclined angle in Table 4, and it was confirmed that there was no change in color even after shaping. Furthermore, in Example 1, after shaping, coloring was observed in the view seen through from the front, but it was the same yellow color as the transmitted color shown by the optical laminate. From these results, even after shaping of the optical laminate, no change in color was observed when observed from an oblique direction, and a correlation was obtained between quantitative evaluation using a measuring device and visual evaluation.

[0174] On the other hand, in Comparative Examples 1 and 2, even when the reflected color of the optical laminate after shaping was observed from the front, the reflected color changed in this state. Furthermore, when observed from an oblique direction, the reflected color changed even more significantly. The scenery seen through the light from the front was observed to have the same color as the transmitted color shown by the optical laminate. From these results, even after shaping of the optical laminate, a change in color was observed when observed from an oblique direction, and a correlation was obtained between quantitative evaluation using a measuring device and visual evaluation.

[0175] From the above results, the optical laminate of the present invention can exhibit a desired reflected color with little change in color even when observed from various angles while having a curved surface. Furthermore, the optical laminate of the present invention can be applied to eyewear (sunglasses, goggles, helmet visors, etc.) that is not only durable but also has excellent design. Furthermore, since the transmitted color of the optical laminate of the present invention can be adjusted, it can also be used as a film that can improve visibility while also having excellent design.

[0176] 10 Cholesteric liquid crystal layer (R or L form) 11 Cholesteric liquid crystal layer (L or R form) 20 Light-reflecting layer 21 First support 22 Second support 23 Polarizing element 24 Second adhesive layer 25 First adhesive layer 30 Measurement stage 31 Light-receiving part of measuring device (position at 0 degrees) 32 Light-receiving part of measuring device when tilted at angle θ (position tilted at angle θ) 33 Sample

Claims

1. An optical laminate comprising: a light-reflecting layer including at least one cholesteric liquid crystal layer in which the absolute value of the difference (|ΔR1-R2|) between the average reflectance (R1) in the wavelength range of 500 nm or more and 700 nm or less and the average reflectance (R2) in the wavelength range of more than 700 nm and 900 nm or less is 10.0 or less; a polarizing element containing at least one dichroic dye; and a first support and a second support that sandwich the light-reflecting layer and the polarizing element, wherein the first support, the light-reflecting layer, the polarizing element, and the second support are laminated in this order, a first adhesive layer is disposed between the light-reflecting layer and the first support, and a second adhesive layer is disposed between the polarizing element and the second support, and the first adhesive layer contains at least one of a hue-adjusting dye and a specific wavelength absorbing dye.

2. The direction perpendicular to the reflection surface of the optical laminate is set to 0 degrees, and the L when the observation position is tilted 60 degrees from the reflection surface ＊ a ＊ b ＊ Hue value a based on color space (CIE 1976) ＊ r and b ＊ In r, the change in the reflected hue of the optical laminate is |Δa ＊ r|≦5.0 and |Δb ＊ The optical laminate according to claim 1, wherein r|≦7.0 is satisfied.

3. L ＊ a ＊ b ＊ Hue value a based on color space (CIE 1976) ＊ s and b ＊ In s, the transmission hue of the optical laminate is ＊ s = -5.0 or more and 5.0 or less, and b ＊ The optical laminate according to claim 1, wherein s = -5.0 or more and 5.0 or less.

4. The optical laminate according to claim 1, wherein the polarizing element has a luminosity-corrected single transmittance of 25% or more and 45% or less, and a luminosity-corrected polarization degree of 90% or more.

5. The optical laminate according to claim 1, wherein the light-reflecting layer comprises at least one cholesteric liquid crystal layer having a right-handed helical direction (R form) and at least one cholesteric liquid crystal layer having a left-handed helical direction (L form).

6. The optical laminate according to claim 1, wherein the hue-adjusting pigment is a dye for coloring resin and comprises at least one pigment selected from the group consisting of: (A) a red pigment having a maximum absorption wavelength in the wavelength range of 400 nm or more and 500 nm or less, (B) a green pigment having a maximum absorption wavelength in the wavelength range of 500 nm or more and 600 nm or less, (C) a blue pigment having a maximum absorption wavelength in the wavelength range of 600 nm or more and 700 nm or less, and (D) a yellow pigment having a maximum absorption wavelength in the wavelength range of 400 nm or more and 450 nm or less.

7. The optical laminate according to claim 1, wherein the first adhesive layer and the second adhesive layer contain an amorphous polyester resin.

8. The optical laminate according to claim 1, wherein the second adhesive layer contains at least one of the hue-adjusting dyes.

9. A polarized lens comprising a lens substrate and the optical laminate according to any one of claims 1 to 8.

10. Eyewear comprising the polarized lens according to claim 9.

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