Polarizing laminate and optical lens

Abstract

Provided is a polarizing laminate in which a first protective layer and a second protective layer are laminated on both surfaces of a polarizing layer via an adhesive layer, the polarizing laminate being characterized in that the polarizing laminate includes a base material layer, the base material layer includes an additive, and the additive satisfies one or more requirements selected from the group consisting of requirements (1) to (3). Requirement (1): the additive includes one or more compounds A selected from the group consisting of stearic acid and a stearate, and the content of the compound A is 10-5000 mass ppm with respect to the base material layer. Requirement (2): the additive includes an ultraviolet absorber, and the content of the ultraviolet absorber is 10-50,000 mass ppm with respect to the base material layer. Requirement (3): the additive includes a heat-resistant stabilizer, and the content of the heat-resistant stabilizer is 10-5000 mass ppm with respect to the base material layer.

Description

Polarizing laminate and optical lens

[0001] The present disclosure relates to a polarizing laminate and an optical lens.

[0002] Optical lenses are used as anti-glare glasses, sunglasses, goggles, corrective glasses, etc. for outdoor activities such as mountain climbing, fishing, and baseball, as well as for driving vehicles, with the aim of blocking light reflected from road surfaces, wall surfaces, snow surfaces, water surfaces, etc. These optical lenses have a laminated structure in which a lens body and a polarizing layer are laminated via an adhesive layer, and a protective layer is usually laminated on the surface of the polarizing layer.

[0003] Patent Document 1 discloses a polarizing laminate that can efficiently impart excellent properties despite its simple structure, the polarizing laminate being composed of a polarizing sheet layer in which protective layers are laminated on both sides of the polarizing layer via an adhesive, the adhesive being composed of an adhesive having an isocyanate group or a urethane group, and the protective layers being composed of a polyamide resin. Patent Document 1 also discloses a lens composed of a polarizing laminate that is composed of a polarizing sheet layer in which protective layers are laminated on both sides of the polarizing layer and a thermoformable resin layer thermally bonded to at least one of the protective layers, the thermoformable resin layer being composed of a polyamide resin.

[0004] Patent document 2 discloses a functional lens in which a lens body, an adhesive layer, and an optical function layer are laminated directly or indirectly in this order, and which is intended to be mounted in a mounting groove of a frame part, and in which the end face facing the mounting groove is formed in a shape such that the apex is located on the mounting side of the adhesive layer in the thickness direction.

[0005] Patent Document 1: JP 2006-227591 A, International Publication No. 2016 / 158680

[0006] However, the present inventors have discovered that in both the polarizing laminate of Patent Document 1 and the functional lens of Patent Document 2, the resin deteriorates due to heating during the manufacturing process, resulting in discoloration to brown or black (so-called fading). Polarizing laminates and lenses that have fading in this way are unsuitable for use as products, resulting in a low manufacturing yield. Therefore, there is a demand for polarizing laminates and optical lenses that are less susceptible to fading.

[0007] An object of the present disclosure is to provide a polarizing laminate and an optical lens that are suppressed from discoloring.

[0008] The present disclosure relates to the following: [1] A polarizing laminate in which a first protective layer and a second protective layer are laminated on both sides of a polarizing layer via an adhesive layer, the polarizing laminate including a substrate layer, the substrate layer including an additive, and the additive satisfying one or more requirements selected from the group consisting of the following requirements (1) to (3): requirement (1): the additive includes one or more compounds A selected from the group consisting of stearic acid and stearates, and the content of the compounds A is 10 to 5,000 ppm by mass relative to the substrate layer; requirement (2): the additive includes an ultraviolet absorber, and the content of the ultraviolet absorber is 10 to 50,000 ppm by mass relative to the substrate layer; and requirement (3): the additive includes a heat resistance stabilizer, and the content of the heat resistance stabilizer is 10 to 5,000 ppm by mass relative to the substrate layer. [2] The polarizing laminate according to [1], wherein the additive satisfies the requirement (2), and the ultraviolet absorber comprises one or more selected from the group consisting of a benzotriazole compound, a triazine compound, and a cyanoacrylate compound. [3] The polarizing laminate according to [1] or [2], wherein the additive satisfies the requirement (3), and the heat resistance stabilizer comprises one or more selected from the group consisting of a phenolic antioxidant, a phosphorus-based antioxidant, and a sulfur-based antioxidant. [4] The polarizing laminate according to any one of [1] to [3], wherein the adhesive layer is a layer containing a cured product of a urethane adhesive. [5] The polarizing laminate according to any one of [1] to [4], wherein the adhesive layer has a thickness of 1.0 to 100.0 μm. [6] The polarizing laminate according to any one of [1] to [5], wherein one or more selected from the group consisting of the first protective layer and the second protective layer comprises a polyamide resin. [7] The polarizing laminate according to [6], wherein the polyamide resin has a structure represented by the following formula (4): (In formula (4), R １ and R ２ each independently represents an alkyl group having 1 to 4 carbon atoms; X ３represents an alkylene group having 1 to 6 carbon atoms, n represents an integer of 1 or more, and p and q each independently represent an integer of 0 to 4.) [8] The polarizing laminate according to any one of [1] to [7], wherein one or more layers selected from the group consisting of the first protective layer and the second protective layer have a retardation value of 300 nm or more. [9] The polarizing laminate according to any one of [1] to [8], wherein the polarizing layer comprises polyvinyl alcohol.

[10] An optical lens comprising the polarizing laminate according to any one of [1] to [9].

[11] The optical lens according to

[10] , wherein the base layer comprises a polyamide resin having a structure represented by the following formula (4): (In formula (4), R １ and R ２ each independently represents an alkyl group having 1 to 4 carbon atoms; X ３ represents an alkylene group having 1 to 6 carbon atoms, n represents an integer of 1 or more, and p and q each independently represent an integer of 0 to 4.

[0009] According to the present disclosure, it is possible to provide a polarizing laminate and an optical lens in which discoloration is suppressed.

[0010] 1 is a cross-sectional view of a polarizing laminate according to one embodiment of the present disclosure.

[0011] The present disclosure will be described below based on specific embodiments. In this specification, when a numerical range is described with a lower limit and an upper limit separately, the numerical range can be a combination of any lower limit and any upper limit. In this disclosure, a numerical range expressed using "A to B" means a numerical range that includes the lower and upper limits, which are the endpoints.

[0012] <Polarizing Laminate> The polarizing laminate of the present disclosure is a polarizing laminate in which a first protective layer and a second protective layer are laminated on both sides of a polarizing layer via an adhesive layer, and the polarizing laminate includes a substrate layer, and the substrate layer includes an additive, and the additive satisfies one or more requirements selected from the group consisting of the following requirements (1) to (3): Requirement (1): The additive includes one or more compounds A selected from the group consisting of stearic acid and stearates, and the content of the compounds A is 10 to 5,000 ppm by mass with respect to the substrate layer. Requirement (2): The additive includes an ultraviolet absorber, and the content of the ultraviolet absorber is 10 to 50,000 ppm by mass with respect to the substrate layer. Requirement (3): The additive includes a heat resistance stabilizer, and the content of the heat resistance stabilizer is 10 to 5,000 ppm by mass with respect to the substrate layer. For example, the additive may satisfy requirement (1), may satisfy requirement (2), may satisfy requirement (3), may satisfy requirements (1) and (2), may satisfy requirements (1) and (3), may satisfy requirements (2) and (3), or may satisfy requirements (1) to (3). Of these, it is preferable that the additive satisfy requirements (1) and (2).

[0013] When the substrate layer contains an additive, and the additive satisfies one or more requirements selected from the group consisting of the above requirements (1) to (3), discoloration of the substrate layer in the polarizing laminate can be suppressed. Requirements (1) to (3) are described in detail below.

[0014] [Requirement (1)] The additive contains one or more compounds A selected from the group consisting of stearic acid and stearates, and the content of compound A is 10 to 5000 ppm by mass relative to the base layer. The content of compound A relative to the base layer is preferably 10 to 3000 ppm by mass, more preferably 10 to 1000 ppm by mass, even more preferably 10 to 500 ppm by mass, particularly preferably 10 to 300 ppm by mass, and especially preferably 10 to 200 ppm by mass. When the content is within the above range, the base layer is less likely to become discolored.

[0015] Although the reason for this effect is unclear, the inventors speculate as follows. Discoloration of the polarizing laminate occurs due to deterioration of the resin caused by heating during the manufacturing process. Resin deterioration is particularly likely to occur in the substrate layer. Compound A can suppress deterioration of the resin caused by heating. If the content of compound A is less than 10 ppm by mass, it becomes difficult to suppress resin deterioration. In addition, blocking of the resin occurs during the manufacturing process. If the content of compound A exceeds 5,000 ppm by mass, although resin deterioration can be suppressed, discoloration of the substrate layer may occur due to deterioration of compound A itself. In other words, by ensuring that the content of compound A in the substrate layer is within the above range, discoloration of the substrate layer can be suppressed and resin blocking can be suppressed. The content of compound A relative to the substrate layer can be adjusted by the amount of compound A added when the substrate layer is manufactured. The content of compound A relative to the substrate layer can be measured by known analytical means such as ICP-spectroscopy (ICP-AES).

[0016] As will be described in detail later, the polarizing laminate has a first protective layer and a second protective layer laminated on both sides of the polarizing layer via an adhesive layer. The polarizing laminate may further include other layers. When focusing particularly on the suppression of discoloration in each layer of the polarizing laminate, the standard for the content (ppm by mass) of compound A in each layer other than the substrate layer in requirement (1) can also be set. For example, when focusing particularly on the suppression of discoloration in the first protective layer of the polarizing laminate, the first protective layer contains an additive, the additive containing one or more compounds A selected from the group consisting of stearic acid and stearates, and the content of compound A is preferably 10 to 5,000 ppm by mass, more preferably 10 to 3,000 ppm by mass, even more preferably 10 to 1,000 ppm by mass, even more preferably 10 to 500 ppm by mass, particularly preferably 10 to 100 ppm by mass, and especially preferably 10 to 50 ppm by mass, relative to the first protective layer. When focusing on the second protective layer, when focusing on the adhesive layer, and when focusing on other layers, the same can be applied as in the case of the first protective layer.

[0017] The additive preferably contains a stearate. The stearate is not particularly limited, but examples thereof include monovalent metal salts such as lithium stearate, sodium stearate, and potassium stearate, and divalent metal salts such as magnesium stearate and calcium stearate. Of these, calcium stearate is more preferred.

[0018] [Requirement (2)] The additive contains an ultraviolet absorber, and the content of the ultraviolet absorber is 10 to 50,000 ppm by mass relative to the substrate layer. The content of the ultraviolet absorber relative to the substrate layer is preferably 10 to 30,000 ppm by mass, more preferably 10 to 10,000 ppm by mass, even more preferably 10 to 5,000 ppm by mass, particularly preferably 10 to 1,000 ppm by mass, and especially preferably 10 to 500 ppm by mass. Within the above range, the substrate layer is less likely to discolor, and the color tone of the substrate layer is also good.

[0019] While the reason for this effect is unclear, the inventors speculate as follows. As described above, discoloration of the polarizing laminate occurs due to deterioration of the resin caused by heating during the manufacturing process. Resin deterioration is particularly likely to occur in the base layer. It is believed that the UV absorber melts upon heating during the manufacturing process of the polarizing laminate and acts as a lubricant. This shortens the residence time of the resin used as the raw material for the polarizing laminate in the manufacturing equipment, reducing the amount of heat applied to the resin. As a result, deterioration of the resin caused by heating is suppressed, and discoloration of the polarizing laminate is less likely to occur. That is, if the content of the UV absorber is less than 10 ppm by mass, the UV absorber's function as a lubricant becomes insufficient, making it difficult to suppress resin deterioration. On the other hand, if the content of the UV absorber exceeds 50,000 ppm by mass, too much UV absorber melts upon heating, which undesirably causes gas generation due to poor dispersion of the UV absorber. In addition, the polarizing laminate may become colored due to the color of the UV absorber. The content of the ultraviolet absorber in the substrate layer can be adjusted by the amount of ultraviolet absorber added when producing the substrate layer. The content of the ultraviolet absorber in the substrate layer can be measured by a known analytical method such as liquid chromatography mass spectrometry (LC / MS).

[0020] As with requirement (1), when particular attention is paid to suppressing discoloration in each layer other than the base layer of the polarizing laminate, the standard for the content (ppm by mass) of the ultraviolet absorber in requirement (2) can also be set for each layer. For example, when particular attention is paid to suppressing discoloration in the first protective layer, the first protective layer contains an additive, the additive contains an ultraviolet absorber, and the content of the ultraviolet absorber relative to the first protective layer is preferably 10 to 50,000 ppm by mass, more preferably 10 to 10,000 ppm by mass, even more preferably 10 to 5,000 ppm by mass, particularly preferably 10 to 1,000 ppm by mass, and especially preferably 10 to 500 ppm by mass. The same can be said when focusing on the second protective layer, the adhesive layer, or the other layers.

[0021] The ultraviolet absorber is not particularly limited as long as it is a compound that absorbs ultraviolet light, and known ultraviolet absorbers can be used. For example, the ultraviolet absorber includes one or more selected from the group consisting of benzoxazine compounds, benzophenone compounds, benzotriazole compounds, triazine compounds, salicylic acid compounds, and cyanoacrylate compounds. Here, for example, the benzoxazine compound refers to a compound having a benzoxazine skeleton, the benzophenone compound refers to a compound having a benzophenone skeleton, the benzotriazole compound refers to a compound having a benzotriazole skeleton, the triazine compound refers to a compound having a triazine skeleton, the salicylic acid compound refers to a compound having a salicylic acid skeleton, and the cyanoacrylate compound refers to a compound having a cyanoacrylate skeleton. Among these, the ultraviolet absorber preferably includes one or more selected from the group consisting of benzotriazole compounds, triazine compounds, and cyanoacrylate compounds, and more preferably includes a benzotriazole compound. Examples of benzotriazole compounds include compounds represented by the following formula (A). Specifically, for example, Tinuvin 326 manufactured by BASF Japan Ltd. can be used. That is, the benzotriazole compound may be 2-(5-chloro-2H-benzotriazol-2-yl)-6-(1,1-dimethylethyl)-4-methylphenol. In formula (A), R ３ each independently represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 3 carbon atoms; R ４ R each independently represents a hydrogen atom, a hydroxyl group, or an alkyl group having 1 to 6 carbon atoms (preferably 1 to 4 carbon atoms). ３ Among R, it is preferred that one or more of them is a halogen atom. The halogen atom is not particularly limited, but may be any halogen atom such as a chlorine atom or a bromine atom, and is preferably a chlorine atom. ４ Preferably, at least one of R is a hydroxyl group. ４ Among these, it is preferred that one or more of them is a tert-butyl group.

[0022] The ultraviolet absorber may be a compound that does not have a benzoyl group. For example, when the ultraviolet absorber contains one or more compounds selected from the group consisting of benzoxazine compounds, benzophenone compounds, benzotriazole compounds, triazine compounds, salicylic acid compounds, and cyanoacrylate compounds, the compound may not have a benzoyl group. The benzoyl group may have any substituent. The ultraviolet absorber may be used alone or in combination of two or more.

[0023] [Requirement (3)] The additive contains a heat stabilizer, and the content of the heat stabilizer is 10 to 5000 ppm by mass relative to the base layer. The content of the heat stabilizer relative to the base layer is preferably 10 to 3000 ppm by mass, more preferably 10 to 1000 ppm by mass, even more preferably 10 to 500 ppm by mass, particularly preferably 10 to 100 ppm by mass, and especially preferably 10 to 50 ppm by mass. When the content is within the above range, the base layer is less likely to become discolored.

[0024] While the reason for this effect is unclear, the inventors speculate as follows. As described above, discoloration of the polarizing laminate occurs due to deterioration of the resin caused by heating during the manufacturing process. Resin deterioration is particularly likely to occur in the base layer. It is believed that the heat stabilizer melts upon heating during the manufacturing process of the polarizing laminate and stabilizes the polymer by capturing excess radicals. This shortens the residence time of the resin used as the raw material for the polarizing laminate in the manufacturing equipment, reducing the amount of heat applied to the resin. As a result, deterioration of the resin caused by heating is suppressed, and discoloration of the polarizing laminate is less likely to occur. That is, if the content of the heat stabilizer is less than 10 ppm by mass, the heat stabilizer's function as a lubricant becomes insufficient, making it difficult to suppress resin deterioration. On the other hand, if the content of the heat stabilizer exceeds 50,000 ppm by mass, too much of the heat stabilizer melts upon heating, and it no longer functions as a lubricant, making it difficult to suppress resin deterioration. The content of the heat stabilizer in the substrate layer can be adjusted by the amount of the heat stabilizer added when producing the substrate layer. The content of the heat stabilizer in the substrate layer can be measured by a known analytical method such as liquid chromatography mass spectrometry (LC / MS).

[0025] As with requirements (1) and (2), when particular attention is paid to suppressing discoloration in each layer other than the base layer of the polarizing laminate, the standard for the content (ppm by mass) of the heat stabilizer in requirement (3) can also be set for each layer. For example, when particular attention is paid to suppressing discoloration in the first protective layer, the first protective layer contains an additive, the additive contains a heat stabilizer, and the content of the heat stabilizer relative to the first protective layer is preferably 10 to 5,000 ppm by mass, more preferably 10 to 3,000 ppm by mass, even more preferably 10 to 1,000 ppm by mass, even more preferably 10 to 500 ppm by mass, particularly preferably 10 to 100 ppm by mass, and especially preferably 10 to 50 ppm by mass. The same can be said when focusing on the second protective layer, the adhesive layer, or the other layers.

[0026] The heat stabilizer is not particularly limited as long as it is a compound that functions as a radical scavenger, and known heat stabilizers can be used. For example, the heat stabilizer includes one or more selected from phenolic antioxidants, phosphorus-based antioxidants, and sulfur-based antioxidants. Here, the phenolic antioxidant is an antioxidant having a phenolic hydroxy group in the molecule. For example, an example of the phenolic antioxidant is a compound having a structure represented by the following formula (B). Specifically, Irganox 1010 manufactured by BASF Japan Ltd. can be used. That is, the phenolic antioxidant may be pentaerythritol tetrakis [3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]. Furthermore, the phosphorus-based antioxidant is an antioxidant having a phosphorus atom in the molecule. Furthermore, the sulfur-based antioxidant is an antioxidant having a sulfur atom in the molecule. In formula (B), R ５ and R ６ each independently represents an alkylene group having 1 to 6 (preferably 1 to 3) carbon atoms; R ７ R each independently represents a hydrogen atom, a hydroxyl group, or an alkyl group having 1 to 6 carbon atoms (preferably 1 to 4 carbon atoms). ７ Preferably, at least one of R is a hydroxyl group. ７ Among these, it is preferred that one or more of them is a tert-butyl group.

[0027] The compound having the structure represented by formula (B) is preferably a compound having a structure represented by the following formula (B-1): In formula (B-1), R ５ and R ６ each independently represents an alkylene group having 1 to 6 (preferably 1 to 3) carbon atoms; R ７ R each independently represents a hydrogen atom, a hydroxyl group, or an alkyl group having 1 to 6 carbon atoms (preferably 1 to 4 carbon atoms). ７ Preferably, at least one of R is a hydroxyl group. ７ Among these, it is preferred that one or more of them is a tert-butyl group.

[0028] The heat stabilizer is preferably a compound having an ester group. The heat stabilizer is preferably a compound having an aromatic ring. The heat stabilizer is preferably a compound composed only of carbon atoms, oxygen atoms, and hydrogen atoms. When the heat stabilizer is a compound having an aromatic ring, the aromatic ring may have any substituent, but preferably has one or more substituents selected from the group consisting of a hydroxyl group and an alkyl group having 1 to 6 carbon atoms. The heat stabilizer may be used alone or in combination of two or more types.

[0029] As described above, the polarizing laminate (200) has a first protective layer and a second protective layer (101, 102) laminated on both sides of a polarizing layer (105) via adhesive layers (103, 104) ( FIG. 1 ). The polarizing laminate (200) also includes a base layer (201). The polarizing laminate may also include other layers. That is, the polarizing laminate may include a polarizing layer (105), a first adhesive layer (103) provided on a first surface of the polarizing layer, a second adhesive layer (104) provided on a second surface of the polarizing layer, a first protective layer (101) provided on a surface opposite the first adhesive layer from the side on which the polarizing layer is located, and a second protective layer (102) provided on a surface opposite the second adhesive layer from the side on which the polarizing layer is located. The arrangement of the substrate layer (201) is not particularly limited. For example, the substrate layer (201) may be provided on the surface of the first protective layer (101) opposite the polarizing layer (105), or on the surface of the second protective layer (102) opposite the polarizing layer (105). This configuration facilitates control of the adhesive strength between the polarizing laminate and the substrate layer. In this configuration, the protective layer (first protective layer or second protective layer) can be used to bond the substrate layer. The method for achieving this configuration is not particularly limited. For example, a method may be used in which a resin is injection-molded onto a laminate in which a first protective layer and a second protective layer are laminated on both sides of a polarizing layer via an adhesive layer, and the laminate and the substrate layer are thermally welded together. Furthermore, another layer may be provided between the substrate layer (201) and the protective layer (first protective layer (101), second protective layer (102)). The following describes each layer that may constitute the polarizing laminate.

[0030] (Polarizing Layer) The polarizing layer is a layer containing a material having polarizing properties. The polarizing layer is not particularly limited, but for example, a stretched film containing a dichroic compound such as iodine or a dichroic dye, and a polarizing resin such as polyvinyl alcohol can be used. The stretched film can be prepared, for example, by subjecting a polyvinyl alcohol film obtained by stretching polyvinyl alcohol to dyeing with a dichroic compound, crosslinking, stretching (uniaxial stretching at a magnification of about 3 to 7 times), and other treatments. That is, the polarizing layer may contain a polarizing resin and may further contain a dichroic compound. The polarizing layer preferably contains polyvinyl alcohol, and more preferably further contains iodine.

[0031] The polyvinyl alcohol is not particularly limited, but examples thereof include saponified vinyl acetate polymers, saponified copolymers of vinyl acetate and copolymerizable monomers other than vinyl acetate (e.g., unsaturated carboxylic acids, unsaturated sulfonic acids, cationic monomers, etc.), and derivatives of these saponified products (e.g., formals, acetals, etc.). Derivatives include polyvinyl acetal and polyvinyl butyral. The number-average polymerization degree of polyvinyl alcohol is not particularly limited, but examples include 1,000 to 10,000 and 3,000 to 5,000. The saponification degree of polyvinyl alcohol is also not particularly limited, but is preferably 85 mol% or more, more preferably 90 mol% or more (e.g., 90 to 100 mol%), and even more preferably 95 mol% or more. Preferred examples include 90 to 100 mol%, 95 to 100 mol%, and 98 to 100 mol%.

[0032] The thickness of the polarizing layer is not particularly limited, but may be, for example, 5.0 to 100.0 μm, preferably 10.0 to 80.0 μm, and more preferably 20.0 to 60.0 μm.

[0033] (Protective Layer) The protective layers (first protective layer and second protective layer) are layers that protect the polarizing layer. The protective layer is not particularly limited as long as it can protect the polarizing layer, and examples thereof include a resin layer. The resin layer may contain one or more selected from the group consisting of thermoplastic resins and thermosetting resins, preferably a thermoplastic resin, and more preferably a thermoplastic resin. Examples of thermoplastic resins include acetyl cellulose resins such as triacetyl cellulose, polycarbonate resins, polyamide resins, polyester resins, olefin resins, acrylic resins, and urethane resins. Among these, polyamide resins are preferred. Examples of polyamide resins are not particularly limited, and examples include aliphatic polyamide resins and aromatic polyamide resins. The aliphatic polyamide resin may have a linear structure, a branched structure, or a cyclic structure. Among these, the aliphatic polyamide resin preferably has a cyclic structure. That is, the polyamide resin is preferably an alicyclic polyamide resin. The alicyclic polyamide resin has excellent transparency. Alicyclic polyamide resins are available as, for example, Trogamid (manufactured by Polypla-Evonik) and Grilamid (manufactured by EMS). The resin layer may contain one or more of these resins. Furthermore, the protective layers (first protective layer and second protective layer) may contain the same material or different materials. That is, one or more selected from the group consisting of the first protective layer and the second protective layer may contain the above-mentioned material.

[0034] The alicyclic polyamide resin can be obtained by combining suitable components selected from the group consisting of alicyclic diamines and alicyclic dicarboxylic acids, aliphatic diamines other than alicyclic diamines, aliphatic dicarboxylic acids other than alicyclic dicarboxylic acids, etc., and polymerizing them using a known method. Examples of alicyclic diamines include compounds represented by the following formula (1): (In formula (1), A １ and A ２ each independently represents a cycloalkylene group having 5 to 10 carbon atoms (preferably 6 to 8, more preferably 6), and X １represents an alkylene group having 1 to 6 carbon atoms (preferably 1 to 4, more preferably 1 to 3).

[0035] The alicyclic dicarboxylic acid may, for example, be a compound represented by the following formula (2). (In formula (2), A ３ and A ４ each independently represents a cycloalkylene group having 5 to 10 carbon atoms (preferably 6 to 8, more preferably 6), and X ２ represents an alkylene group having 1 to 6 carbon atoms (preferably 1 to 4, more preferably 1 to 3).

[0036] When an alicyclic diamine is used, it is preferable to use an aliphatic dicarboxylic acid other than an alicyclic dicarboxylic acid (hereinafter also referred to as aliphatic dicarboxylic acid A). Examples of the aliphatic dicarboxylic acid A include compounds represented by the following formula (3). (In formula (3), m is an integer of 1 or more, preferably 4 to 18, more preferably 6 to 16, and even more preferably 8 to 14.)

[0037] The alicyclic polyamide resin preferably has a structure represented by the following formula (4). (In formula (4), R １ and R ２ each independently represents an alkyl group having 1 to 4 carbon atoms (preferably 1 to 2), and X ３ represents an alkylene group having 1 to 6 carbon atoms (preferably 1 to 4, more preferably 1 to 3), n represents an integer of 1 or more (preferably 4 to 18, more preferably 6 to 16, even more preferably 8 to 14), and p and q each independently represent an integer of 0 to 4 (preferably 0 to 3, more preferably 0 to 2, even more preferably 0 to 1).

[0038] The number average molecular weight of the polyamide resin is not particularly limited, but is, for example, 0.6 × 10 ４ ~3.0 x 10 ５ may be 0.6×10 ４ ~2.0 x 10 ５ It is preferable that the ４ ~1.5 x 10 ５ More preferably, it is 2.0 × 10４ ~1.0 x 10 ５ The number average molecular weight of the polyamide resin can be measured by gel permeation chromatography (GPC) and can be calculated in terms of polystyrene.

[0039] The thickness of the protective layer is not particularly limited, but may be, for example, 20.0 to 2000.0 μm, preferably 50.0 to 800.0 μm, more preferably 80.0 to 600.0 μm, and even more preferably 100.0 to 500.0 μm. The thicknesses of the protective layers (first protective layer and second protective layer) may be the same or different.

[0040] The retardation value of the protective layer is not particularly limited, but it is preferable that one or more selected from the group consisting of the first protective layer and the second protective layer have a retardation value of 300 nm or more, and in particular, it is preferable that the retardation value of the first protective layer be 300 nm or more. By setting the retardation value of the first protective layer to 300 nm or more, the generation of white spots in the protective layer can be suppressed. The retardation value is preferably 300 to 20,000 nm, more preferably 350 to 15,000 nm, even more preferably 400 to 10,000 nm, even more preferably 450 to 5,000 nm, particularly preferably 500 to 4,000 nm, and especially preferably 550 to 3,000 nm. When the protective layer is formed by stretching, the retardation value is defined as Δn·d, where Δn is the difference in refractive index between the stretching direction and the refractive index in the direction perpendicular thereto, and d is the thickness of the protective layer. The retardation value can be controlled by the stretching ratio when producing the protective layer, the amount of resin discharged, and the thickness of the protective layer.

[0041] (Adhesive Layer) The adhesive layer is not particularly limited as long as it can bond the protective layer and the polarizing layer, but is preferably a layer containing a cured adhesive. The adhesive may be a solution-based adhesive or a hot-melt adhesive. The method for curing the adhesive is not particularly limited, and known methods can be used. For example, in the case of a solution-based adhesive, the cured adhesive can be obtained by volatilizing the solvent contained in the adhesive solution. In the case of a two-component curing adhesive, the cured adhesive can be obtained by mixing a solution containing a base agent and a solution containing a curing agent. In the case of a hot-melt adhesive, the cured adhesive can be obtained by cooling and solidifying the molten adhesive. Examples of adhesives include vinyl acetate adhesives, acrylic adhesives, polyester adhesives, urethane adhesives, and epoxy adhesives. Among these, urethane adhesives are preferred. Urethane adhesives refer to adhesives containing polyurethane resins or adhesives containing an isocyanate component and a diol component. That is, the urethane adhesive may be a one-component adhesive containing polyurethane resin, or a two-component curing adhesive (i.e., a reactive curing adhesive) containing an isocyanate component and a diol component. As the isocyanate component and the diol component, a urethane prepolymer obtained by reacting an isocyanate component and a diol component can also be used.

[0042] The adhesive layer may contain one or more of these materials. The adhesive layers (first adhesive layer and second adhesive layer) may contain the same material or different materials. A vinyl acetate adhesive refers to an adhesive containing a vinyl acetate resin, an acrylic adhesive refers to an adhesive containing an acrylic resin, a polyester adhesive refers to an adhesive containing a polyester resin, and an epoxy adhesive refers to an adhesive containing an epoxy resin and a curing agent.

[0043] The thickness of the adhesive layer is not particularly limited, but may be, for example, 0.1 to 200.0 μm, preferably 1.0 to 100 μm, more preferably 1.5 to 80.0 μm, even more preferably 2.0 to 50.0 μm, even more preferably 3.0 to 25.0 μm, particularly preferably 5.0 to 20.0 μm, and especially preferably 5.0 to 15.0 μm. The thicknesses of the adhesive layers (first adhesive layer and second adhesive layer) may be the same or different.

[0044] (Substrate Layer) The material used for the substrate layer is not particularly limited, but it is preferable that the substrate layer contains a resin, and more preferably a polyamide resin. That is, it is more preferable that the substrate layer is a polyamide resin layer. By including a polyamide resin layer, an optical lens having high lightness, toughness, and chemical resistance can be formed. As the resin, the resins described in the protective layer section can be used, and as the polyamide resin, the polyamide resins described in the protective layer section can be used. In addition, the substrate layer may contain various additives other than the additive, such as a plasticizer, a colorant, a flame retardant, an antistatic agent, etc.

[0045] The thickness of the substrate layer is not particularly limited, but may be, for example, 1 to 20 mm, preferably 2 to 20 mm, more preferably 3 to 10 mm, and even more preferably 3 to 5 mm.

[0046] The shape of the polarizing laminate is not particularly limited, and may be flat or curved. The method for forming the polarizing laminate into a curved shape is not particularly limited, and an example of the method is to form a flat polarizing laminate and then subject the polarizing laminate to bending processing.

[0047] <Optical Lens> The optical lens preferably includes a polarizing laminate. The optical lens may have other layers. For example, the optical lens may have a hard coat layer, an anti-reflection layer, an anti-fogging layer, etc. The locations of these layers are not particularly limited as long as they can perform their functions, but they are preferably included on the surface of the optical lens.

[0048] The shape of the optical lens is not particularly limited, and may be flat or curved. Specifically, it may be a concave lens, a convex lens, or a concave-convex lens. The shape of the optical lens can be adjusted by a known method, for example, by injection molding a polyamide resin onto a curved polarizing laminate.

[0049] The methods for measuring and evaluating the physical properties of the polarizing laminate and the optical lens will be described below.

[0050] <Method for measuring retardation value> The retardation value of the protective layer can be measured using a "KOBRA-WPR" (590 nm) manufactured by Otsuka Measuring Instruments Co., Ltd. In the case of a laminate, a sharp blade such as a cutter knife is inserted into the interface between the protective layer and the polarizing layer of the laminate to separate the two layers. If an adhesive layer is attached to the protective layer, the part of the protective layer that is not attached is measured, or the adhesive layer is scraped off with a cutter knife or the like and only the protective layer is measured.

[0051] <Method for evaluating blocking (Test 1)> In accordance with JIS K-6720-2 (ISO 1060-2), the bulk density of an injection molding material is measured three times. The difference between the maximum and minimum bulk density values ​​obtained is then divided by the arithmetic mean value of the three values, and the value is used to evaluate blocking according to the following criteria.

[0052] [Evaluation Criteria] A: The value of {(maximum value - minimum value) / arithmetic mean value} x 100 is less than 10. B: The value of {(maximum value - minimum value) / arithmetic mean value} x 100 is 10 or more.

[0053] <Method for Evaluating Ultraviolet Transmittance (Test 2)> Measurement was carried out in accordance with JIS K7375 (ISO 13468-2) using a color difference meter (CM5 manufactured by Konica Minolta) using a polarizing laminate having a thickness of 2 mm.

[0054] [Evaluation Criteria] A: The transmittance at 400 nm is 10% or less. B: The transmittance at 400 nm is more than 10%.

[0055] <Evaluation method for discoloration (Test 3)> A 2 mm thick laminate not including an injection molding material or a polarizing layer is left in an environment at 200°C for 30 minutes, and the color difference is measured using reflected light with a spectrophotometer (CM5 manufactured by Konica Minolta).

[0056] [Evaluation Criteria] A: Color difference ΔE is less than 3. B: Color difference ΔE is 3 or more.

[0057] <Method for Evaluating Discoloration (Test 4)> Discoloration was evaluated by using a microscope (Keyence, VHX-7000) to irradiate the lens with transmitted light and observing the size of the discoloration (black or brown foreign matter).

[0058] [Evaluation Criteria] A: Less than 3 scorches having a diameter of more than 50 μm are observed. B: 3 or more scorches having a diameter of more than 50 μm are observed.

[0059] <Overall Evaluation> Evaluation was made according to the following criteria: A: All evaluation results from the above evaluation methods were rated A. B: One or more evaluation results from the above evaluation methods were rated B.

[0060] The configurations and combinations thereof in each embodiment are merely examples, and additions, omissions, substitutions, and other modifications of the configurations are possible as appropriate within the scope of the spirit of the present invention. The present disclosure is not limited to the embodiments, but is limited only by the scope of the claims.

[0061] The present disclosure will be specifically described below with reference to examples, but the present disclosure is not limited to the aspects of the following examples.

[0062] Example 1: An alicyclic polyamide resin (TROGAMID (registered trademark) myCX) was heated and melted using a film extruder adjusted to 280-300°C. The sheet extruded from a T-die was then cooled using a cooling roll and then uniaxially stretched at a stretch ratio of 1.50x using rolls rotating at different speeds while reheating, yielding a polyamide sheet with a thickness of 200 μm. One side of the resulting polyamide sheet was coated with a polyurethane adhesive (a 100:15 mixture of Toyo-Morton's two-component adhesives "TM-593" and "CAT-RT30" at a mass ratio of 100:15) to a thickness of 10 μm. The adhesive-coated side of the polyamide sheet was bonded to both sides of a polarizing film (manufactured by Nippon Kayaku Co., Ltd.) containing polyvinyl alcohol and approximately 40 μm thick to form a polarizing plate (laminate). The resulting polarizing plate was cut into the desired shape (a pair of opposing edges of a roughly rectangular shape curved outward in a roughly arc shape) using a Thomson blade. The cut polarizing plate was preheated at approximately 100°C for 1 to 2 minutes and then placed on a concave mold with a curvature radius of 87 mm and temperature-controlled at approximately 100°C. It was then vacuum-suctioned through suction holes in the bottom of the mold and bent to obtain a polarizing plate (laminate) with a curved surface shape. The injection molding material was prepared by sprinkling calcium stearate (manufactured by Shiraishi Calcium Co., Ltd.) as Compound A onto an alicyclic polyamide resin (Trogamid (registered trademark) myCX) so that the concentration of the compound A was 200 ppm by mass relative to the injection molding material.

[0063] A polarizing plate having a curved surface was then placed on the concave surface of a lens mold installed in an injection molding machine, and the mold was closed. The injection molding material prepared by the above method, which had been melt-kneaded at 280°C, was then injected at a pressure of 200 MPa to mold a polarizing laminate (polarizing lens). The resulting polarizing lens was processed into the shape of a lens to be fitted using a lens processing machine, yielding an optical lens in which the lens edge after processing had the following structure: first protective layer 101 / first adhesive layer 103 / polarizing layer 105 / second adhesive layer 104 / second protective layer 102 / substrate layer 201.

[0064] The polarizing laminate was evaluated according to the above-mentioned evaluation methods and criteria, and the evaluation results are shown in Table 1-1.

[0065] Examples 2 to 60 Polarizing laminates were obtained in the same manner as in Example 1, except that the contents of Compound A, UV absorber, and heat stabilizer were changed to the values ​​shown in Tables 1-1 and 1-2. The physical properties of the resulting polarizing laminates are shown in Tables 1-1 and 1-2. When adding a UV absorber or heat stabilizer to the injection-molded resin, a material prepared by previously mixing an alicyclic polyamide resin (TROGAMID (registered trademark) myCX) with a UV absorber (TINUVIN 326, manufactured by BASF Japan) and a heat stabilizer (IRGANOX 1010, manufactured by BASF Japan), or either one alone, was melt-kneaded at 280°C using a twin-screw extruder to produce cylindrical resin pellets. Calcium stearate (manufactured by Shiraishi Calcium Co., Ltd.) was then sprinkled on the resin pellets as Compound A to produce a material for injection molding.

[0066] [Comparative Examples 1 to 13] Polarizing laminates were obtained in the same manner as in Example 1, except that the content of Compound A, the content of UV absorber, and the content of heat stabilizer were changed to the values ​​shown in Tables 1-1 and 1-2. The physical properties of the obtained polarizing laminates are shown in Tables 1-1 and 1-2. When an UV absorber or heat stabilizer was added to the injection molding resin, the same method as described in the above columns for Examples 2 to 60 was used. In Tables 1-1 and 1-2, Compound A indicates the content (ppm by mass) of stearic acid or a stearate salt in the injection molding material, UV absorber indicates the content (ppm by mass) of the UV absorber in the injection molding material, and heat stabilizer indicates the content (ppm by mass) of the heat stabilizer in the injection molding material.

[0067] According to the present disclosure, it is possible to provide a polarizing laminate and an optical lens in which discoloration is suppressed.

[0068] 200 Polarizing laminate, 101 First protective layer, 102 Second protective layer, 103 First adhesive layer, 104 Second adhesive layer, 105 Polarizing layer, 201 Base layer

Claims

1. A polarizing laminate in which a first protective layer and a second protective layer are laminated on both sides of a polarizing layer via an adhesive layer, the polarizing laminate including a base layer, the base layer including an additive, and the additive satisfying one or more requirements selected from the group consisting of the following requirements (1) to (3): requirement (1): the additive includes one or more compounds A selected from the group consisting of stearic acid and stearates, and the content of the compounds A is 10 to 5,000 ppm by mass relative to the base layer; requirement (2): the additive includes an ultraviolet absorber, and the content of the ultraviolet absorber is 10 to 50,000 ppm by mass relative to the base layer; requirement (3): the additive includes a heat stabilizer, and the content of the heat stabilizer is 10 to 5,000 ppm by mass relative to the base layer.

2. The polarizing laminate according to claim 1, wherein the additive satisfies the requirement (2), and the ultraviolet absorber includes one or more selected from the group consisting of a benzotriazole compound, a triazine compound, and a cyanoacrylate compound.

3. The polarizing laminate according to claim 1 or 2, wherein the additive satisfies the requirement (3), and the heat resistance stabilizer includes one or more selected from the group consisting of a phenol-based antioxidant, a phosphorus-based antioxidant, and a sulfur-based antioxidant.

4. The polarizing laminate according to any one of claims 1 to 3, wherein the adhesive layer is a layer containing a cured product of a urethane adhesive.

5. The polarizing laminate according to any one of claims 1 to 4, wherein the adhesive layer has a thickness of 1.0 to 100.0 µm.

6. The polarizing laminate according to any one of claims 1 to 5, wherein at least one selected from the group consisting of the first protective layer and the second protective layer contains a polyamide resin.

7. The polarizing laminate according to claim 6, wherein the polyamide resin has a structure represented by the following formula (4): (In formula (4), R １ and R ２ each independently represents an alkyl group having 1 to 4 carbon atoms; ３ represents an alkylene group having 1 to 6 carbon atoms, n represents an integer of 1 or more, and p and q each independently represent an integer of 0 to 4.

8. The polarizing laminate according to any one of claims 1 to 7, wherein the retardation value of one or more layers selected from the group consisting of the first protective layer and the second protective layer is 300 nm or more.

9. The polarizing laminate according to any one of claims 1 to 8, wherein the polarizing layer contains polyvinyl alcohol.

10. An optical lens comprising the polarizing laminate according to any one of claims 1 to 9.

11. The optical lens according to claim 10, wherein the substrate layer contains a polyamide resin having a structure represented by the following formula (4): (In formula (4), R １ and R ２ each independently represents an alkyl group having 1 to 4 carbon atoms; ３ represents an alkylene group having 1 to 6 carbon atoms, n represents an integer of 1 or more, and p and q each independently represent an integer of 0 to 4.

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