Optical molded body

Abstract

This invention provides an optical molded body that exhibits high shape stability and optical performance stability even after storage in high temperature and high humidity environments. The optical molded body is characterized by comprising, in sequence, a resin substrate, a moisture-proof layer, and an optical functional layer; the moisture-proof layer is an amorphous film containing aluminum, silicon, oxygen, and carbon; and the optical functional layer is an anti-reflective film and / or a partially reflective film.

Description

[Technical Field]

[0001] This invention relates to a molded body for optical applications. [Previous Technology]

[0002] Previously, glass was used in optical molding systems such as lenses or prisms. However, in recent years, due to the high degree of design freedom, such as lightweighting, miniaturization, or aspherical lenses, resin materials have gradually begun to be used. Furthermore, in recent years, the performance of optical products such as VR (virtual reality) and AR (augmented reality) has improved dramatically, and the precision of the internal optical design of optical products has also increased. Therefore, regardless of whether it is made of glass or resin, not only at room temperature, but also in harsh environments such as high temperature and high humidity, the requirements for the stability of optical properties such as shape stability or refractive index of optical moldings have become very stringent.

[0003] However, resin materials suffer from the problem that their optical properties, such as the shape or refractive index, change due to moisture absorption. To address this issue, attempts have been made to form a moisture-proof coating on the surface of an optical molded article containing a resin substrate. Patent Document 1 discloses a technique for covering the external air contact surface of an optical molded article with a polycrystalline moisture-proof coating. [Prior Art Documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2006-146025 [Summary of the Invention]

[0005] [Problem to be solved by the invention] The inventors have discovered through research that the optical molded body containing a moisture-proof film obtained by the above-mentioned prior art method cannot obtain sufficient moisture resistance and cannot suppress the performance changes caused by moisture absorption when stored in a high temperature and high humidity environment.

[0006] Therefore, the present invention was made in view of the above-mentioned problems, and its object is to provide an optical molded body that exhibits high shape stability and optical performance stability even after storage in high temperature and high humidity environments. [Technical Means for Solving the Problem]

[0007] That is, the present invention is as follows. [1] An optical molded body, characterized in that: the optical molded body sequentially comprises a resin substrate, a moisture-proof layer, and an optical functional layer, wherein the moisture-proof layer is an amorphous film containing aluminum, silicon, oxygen, and carbon, and the optical functional layer is an anti-reflective film and / or a partial reflective film. [2] The optical molded body described in [1] is characterized in that: the moisture-proof layer further contains nitrogen. [3] The optical molded body described in [1] or [2] is characterized in that: the moisture-proof layer comprises an aluminum-based composition layer containing aluminum, oxygen, and carbon. [4] The optical molded body described in [3] is characterized in that: in the moisture-proof layer, the aluminum-based composition layer comprises a layer with a carbon content of 0.1 to 10 atomic%. [5] The optical molded body described in [3] or [5] is characterized in that: in the moisture-proof layer, the total content of aluminum, oxygen, and carbon in the aluminum-based composition layer is 70 atomic% or more. [6] An optical molded article as described in any one of [1] to [5] is characterized in that: the moisture-proof layer comprises a silicon-based composition layer containing silicon, oxygen, and nitrogen. [7] An optical molded article as described in [6] is characterized in that: in the moisture-proof layer, the silicon-based composition layer comprises a layer with a nitrogen content of 0.1 to 10 atomic% [8] An optical molded article as described in [6] or [7] is characterized in that: in the moisture-proof layer, the total content of silicon, oxygen, and nitrogen in the silicon-based composition layer is 70 atomic% or more. [9] An optical molded article as described in any one of [6] to [8] is characterized in that: the moisture-proof layer comprises an alternating laminated structure of the aluminum-based composition layer and the silicon-based composition layer.

[10] The optical molded article as described in [9] is characterized in that: in the above-mentioned moisture-proof layer, the ratio of the total thickness of the aluminum-based constituent layers to the total thickness of the silicon-based constituent layers (aluminum-based constituent layers: silicon-based constituent layers) is 1:4 to 4:1.

[11] The optical molded article as described in

[10] is characterized in that: in the above-mentioned alternating layered structure, the total number of layers is 6 or more.

[12] The optical molded article as described in

[11] is characterized in that: the moisture-proof layer covers the entire surface of the molded article, and the film thickness distribution is within 10%.

[13] The optical molded article as described in any one of [1] to

[12] is characterized in that: the above-mentioned resin substrate is formed from any one or more resins selected from the group consisting of methacrylic resins, polyester resins, carbonate resins, norcamphene resins, and modified norcamphene resins. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide an optical molded body that has sufficient moisture-proof properties and high shape stability and optical performance stability even after being stored in a high temperature and high humidity environment.

Implementation Method

[0009] Hereinafter, the form in which the present invention is implemented (hereinafter referred to as "this embodiment") will be described in detail, but the present invention is not limited to the following description and can be implemented with various changes within the scope of its spirit.

[0010] <Optical Molded Body> The optical molded body of this embodiment sequentially includes a resin substrate, a moisture-proof layer, and an optical functional layer. Here, "sequentially" refers to the order of layering (i.e., "sequentially layered"). The optical molded body of this embodiment may also have additional layers other than those mentioned above. Examples of additional layers include: functional layers such as anti-fouling layers, water-repellent layers, oil-repellent layers, and hard coatings; blackening layers to suppress light incident from the side; pretreatment layers to improve the adhesion of each layer; and base coatings. Without impairing the effect of this embodiment, the additional layers can be arranged in any location, such as between the resin substrate and the moisture-proof layer, between the moisture-proof layer and the optical functional layer, or on top of the optical functional layer.

[0011] <Resin Substrate> The resin substrate in this embodiment may be a resin molded body.

[0012] The shape of the resin substrate described above is not particularly limited. For example, it can be used in various forms such as film, sheet, plate, curved surface, bowl, lens, block, sphere, rod, cylinder, tube, and fiber. In addition to the above-mentioned shapes, shapes with fine shaped features applied to its surface can also be used. As a more specific example, the shape of the substrate in this embodiment can also be a lens, prism, light guide, or diffraction grating.

[0013] There is no particular limitation on the manufacturing method of the above-mentioned resin substrate, and known methods can be used. For example, injection molding, extrusion molding, compression molding, injection compression molding, vacuum forming, air-pressing molding, blow molding, casting polymerization, etc. can be used. Alternatively, the substrate can be obtained by grinding or turning the molded body obtained by the above-mentioned manufacturing method.

[0014] The size of the resin substrate described above is not particularly limited. However, from the viewpoint of ease of operation and productivity in the film-forming process, it is preferable to have ϕ1 mm or more, more preferably ϕ5 mm or more, further preferably ϕ10 mm or more, further preferably ϕ20 mm or more, especially preferably ϕ30 mm or more, preferably ϕ300 mm or less, more preferably ϕ200 mm or less, further preferably ϕ150 mm or less, further preferably ϕ120 mm or less, and especially preferably ϕ100 mm or less. Furthermore, the above size can be set as the size of one surface shape of the substrate. Also, it can be set as the diameter in the case of a roughly circular shape (for example, the length of the major axis in the case of an ellipse).

[0015] The thickness of the aforementioned resin substrate is preferably 0.1 mm or more, more preferably 0.2 mm or more, further preferably 0.3 mm or more, even more preferably 0.5 mm or more, preferably 100 mm or less, even more preferably 50 mm or less, further preferably 30 mm or less, and even more preferably 25 mm or less. Here, the thickness refers to the distance between the main surface of the resin substrate and its opposite surface. If the resin substrate is lens-shaped, the maximum distance in the optical axis direction between the light incident surface and its opposite surface can be used. If the resin substrate is prism-shaped, the smaller of the smaller distance between the light incident surface and its opposite surface (in the case of multiple opposite surfaces, the farthest surface can be selected) or the distance between the base surfaces of a polygonal prism can be used. If the resin substrate is cylindrical or elliptical, the smaller of the smaller of the minimum outer diameter length or the distance between the base surfaces can be used. In the case of a substrate with transversely incident light, such as a light guide plate, this represents the maximum distance between the light emitting surface and the surface on its opposite side.

[0016] When the substrate surface has fine textures, the specific surface area of ​​the resin substrate is preferably 0.1 mm⁻¹ or more, more preferably 0.3 mm⁻¹ or more, particularly preferably 0.5 mm⁻¹ or more, preferably 10 mm⁻¹ or less, more preferably 8 mm⁻¹ or less, and particularly preferably 5 mm⁻¹ or less. When the substrate surface does not have fine textures, the specific surface area is preferably 0.01 mm⁻¹ or more, more preferably 0.1 mm⁻¹ or more, particularly preferably 0.3 mm⁻¹ or more, more preferably 5 mm⁻¹ or less, more preferably 4 mm⁻¹ or less, and particularly preferably 3 mm⁻¹ or less. If the specific surface area is within this range, it is preferable from the viewpoint of balancing the surface functionality as an optical element with the shape change of the molded body associated with the penetration of moisture from the surface of the molded body. Here, specific surface area refers to the surface area per unit volume of the substrate.

[0017] The above-mentioned resin substrate can also be a thermoplastic resin.

[0018] Examples of thermoplastic resins include: methacrylic resins, polycarbonate resins, polyester resins, aromatic polyamide resins, polyolefin resins, modified polyolefin resins, modified norcamphene resins, norcamphene resins, cyclic block copolymers (CBC), triacetin cellulose (TAC), polyphenylene sulfide (PPS), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyethylene naphthalate (PEN), polyoxymethylene (POM), polyether ether ketone (PEEK), ABS resin, polyamide, polyimide, etc. Since the material is intended for optical applications, excellent transparency is desirable. In this regard, methacrylic resins, polycarbonate resins, polyester resins, modified norbornene resins, TAC, PET, and PEN are preferred. More preferably, the material is selected from any one of the group consisting of methacrylic resins, polyester resins, carbonate resins, modified norbornene resins, TAC, and PET. Even more preferably, the material is selected from any one of the group consisting of methacrylic resins, polyester resins, carbonate resins, and modified norbornene resins. Furthermore, from the viewpoint of low birefringence, methacrylic resins are particularly preferred.

[0019] The above-mentioned thermoplastic resin can be used alone or in combination with two or more. Furthermore, additives can be selectively formulated at will. There are no particular limitations on the additives used, as long as they can achieve the effects of this invention, and they can be appropriately selected according to the purpose.

[0020] (Methacrylic Resin) When using a methacrylic resin as the aforementioned thermoplastic resin, a homopolymer of methyl methacrylate (MMA) or a copolymer of MMA with other monomers can be used. From the viewpoint of thermal stability, heat resistance, and low birefringence, copolymers are preferred, and random copolymers are even more preferred. The composition of the methacrylic resin is not particularly limited, and may be configured to include 50-100 wt% of methacrylic ester monomer units (A), 0-30 wt% of structural units (B) having a ring structure in the main chain and / or side chains, and 0-20 wt% of other vinyl monomer units (C) that can copolymerize with the methacrylic ester monomer.

[0021] The methacrylate monomer unit (A) is not limited to the following, but may include, for example: methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, tributyl methacrylate, 2-ethylhexyl methacrylate, cyclopentyl methacrylate, cyclohexyl methacrylate, cyclooctyl methacrylate, tricyclodecyl methacrylate, isocamphenyl methacrylate, phenyl methacrylate, benzyl methacrylate, 1-phenylethyl methacrylate, 2-phenoxyethyl methacrylate, 3-phenylpropyl methacrylate, 2,4,6-tribromophenyl methacrylate, etc. From the viewpoint of the heat resistance, optical properties, and weather resistance of the obtained methacrylate resin, the above-mentioned methacrylate monomers are preferably methyl methacrylate, ethyl methacrylate, cyclohexyl methacrylate, phenyl methacrylate, and benzyl methacrylate; from the viewpoint of ease of acquisition, methyl methacrylate and benzyl methacrylate are preferred. The above-mentioned methacrylate monomers may be used alone or in combination with two or more.

[0022] By appropriately adjusting the ratio of the methacrylate monomer unit (A) of the aforementioned methacrylate resin to the structural unit (B) having a ring structure in the main chain and / or side chain, and other vinyl monomer units (C) that can copolymerize with the methacrylate monomer, the resin-made optical element of this embodiment can be sufficiently endowed with thermal stability, heat resistance, good hue, and low hygroscopicity, and birefringence caused by alignment or residual stress during molding can be reduced. From these viewpoints, the content of the methacrylate monomer unit (A) relative to 100 wt% of the methacrylate resin is preferably 50 wt% or more, more preferably 55 wt% or more, and even more preferably 60 wt%. It is also preferably 100 wt% or less, more preferably 95 wt% or less, and even more preferably 90 wt% or less.

[0023] The structural unit (B) having a ring structure in the main chain and / or side chain is not limited to the following, but preferably has at least one structural unit selected from the group consisting of maleimine structural units (B-1), glutaric anhydride structural units (B-2), glutaric anhydride structural units (B-3), lactone ring structural units (B-4), acid anhydride structural units (B-5), aromatic structural units (B-6), and alicyclic structural units (B-7). The structural unit (B) having a ring structure in the main chain and / or side chain may be used alone or in combination with two or more types.

[0024] As the maleimide structural unit (B-1) constituting the above-mentioned methacrylic resin, the structural unit represented by the following general formula (1) is suitable. [Chemical 1] In the above general formula (1), R1 represents any one of the group consisting of hydrogen atom, alkyl with 1 to 14 carbon atoms, cycloalkyl with 3 to 14 carbon atoms, alkoxy with 1 to 14 carbon atoms, aralkyl with 7 to 14 carbon atoms, and aryl with 6 to 14 carbon atoms. The alkyl, cycloalkyl, alkoxy, aralkyl, and aryl groups may also have substituents on the carbon atoms.

[0025] The monomer used to form the maleimide structural unit (B-1) is not limited to the following, but may include, for example: maleimide; N-methylmaleimide, N-ethylmaleimide, N-n-propylmaleimide, N-isopropylmaleimide, N-n-butylmaleimide, N-isobutylmaleimide, N-tert-butylmaleimide, N-n-pentylmaleimide, N-n-hexylmaleimide, N-n-heptylmaleimide, N-n-octyl N-alkyl-substituted maleimides such as maleimide and N-lauryl maleimide; N-cyclopentyl maleimide, N-cyclohexyl maleimide, 1-cyclohexyl-3-methyl-1H-pyrrole-2,5-dione, 1-cyclohexyl-3,4-dimethyl-1H-pyrrole-2,5-dione, 1-cyclohexyl-3-phenyl-1H-pyrrole-2,5-dione, 1-cyclohexyl-3,4-diphenyl-1H-pyrrole-2,5-dione, etc. N-Phenylacetinimide, N-Benzylmaleimide, N-(2-Chlorophenyl)maleimide, N-(4-Chlorophenyl)maleimide, N-(4-Bromophenyl)maleimide, N-(2-Methylphenyl)maleimide, N-(2,6-Dimethylphenyl)maleimide, N-(2-Ethylphenyl)maleimide, N-(2-Methoxyphenyl)maleimide, N-(2-Nitrophenyl)maleimide, N-(2,4,6-Trimethylphenyl)maleimide N-aryl-substituted maleimides include malimines such as methyl-1-phenyl-1H-pyrrole-2,5-dione, 3,4-dimethyl-1-phenyl-1H-pyrrole-2,5-dione, 1,3-diphenyl-1H-pyrrole-2,5-dione, and 1,3,4-triphenyl-1H-pyrrole-2,5-dione. The above-mentioned maleimide structural unit (B-1) can be used alone or in combination of two or more.

[0026] When the methacrylic resin is set to 100% by mass, the content of maleimide structural unit (B-1) is preferably 1 to 70% by mass, more preferably 3 to 60% by mass, and even more preferably 5 to 40% by mass. If the content of maleimide structural unit (B-1) is within the above range, it is preferable to obtain a resin with good molding processability, heat resistance, optical properties, low birefringence, and low water absorption.

[0027] The methacrylic resin containing the maleimide structural unit (B-1) may, as needed, further include aromatic vinyl monomer units, unsaturated nitrile monomer units, and other structural units derived from monomers that can copolymerize with the methacrylate monomer unit (A) and the maleimide structural unit (B-1). There are no particular limitations on the aromatic vinyl monomer; examples include styrene and α-methylstyrene, with styrene being preferred. There are no particular limitations on the unsaturated nitrile monomer; examples include acrylonitrile, methacrylonitrile, and ethylacrylonitrile, with acrylonitrile being preferred.

[0028] The glutaric anhydride structural unit (B-2) constituting the above-mentioned methacrylic resin is preferably represented by the structural unit represented by the following general formula (2). [Chemical 2] In the above general formula (2), R1 and R2 independently represent hydrogen atoms or substituted or unsubstituted alkyl groups having 1 to 6 carbon atoms, which may also be substituted with hydroxyl groups.

[0029] The method for forming the above-mentioned glutaric anhydride structural unit (B-2) is not particularly limited. For example, a method can be described in which the monomer of the structure represented by the following general formula (3) is copolymerized with the monomer constituting the above-mentioned methacrylate monomer unit (A), and then cyclized by heat treatment in the presence or absence of a catalyst. [Chemical 3] In the above general formula (3), R1 represents a hydrogen atom, or a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, which may also be substituted with a hydroxyl group. R2 represents a hydrogen atom, or a third butyl group.

[0030] Furthermore, as long as it is within the range that can exert the effects of the present invention, the monomer of the structure represented by general formula (3) can also remain in the methacrylic resin in an unreacted state.

[0031] The pentylene imine structural unit (B-3) constituting the above-mentioned methacrylic resin can be formed after resin polymerization. As the (B-3) structural unit, it is suitable to use the structural unit represented by the following general formula (4). [Chemical 4] In the above general formula (4), R1 and R2 independently represent a hydrogen atom or a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, which may also be substituted with a hydroxyl group. Furthermore, R3 represents any one of the group consisting of a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 6 to 14 carbon atoms, and a substituted or unsubstituted aryl group having 6 to 18 carbon atoms. It is particularly suitable that R1, R2, and R3 are all methyl groups.

[0032] The above-mentioned pentadienylimine structural unit (B-3) can be used alone or in combination of two or more.

[0033] The methacrylic resin is set to 100% by mass, and the content of the pentylene imide structural unit (B-3) is preferably 1 to 70% by mass, more preferably 3 to 60% by mass. If the content of the pentylene imide structural unit (B-3) is within the above range, it is better to obtain a resin with good processability, heat resistance, optical properties, and low birefringence. Furthermore, the content of the pentylene imide structural unit (B-3) can be calculated, for example, by the method described in International Publication No. 2015 / 098096

[0136] to

[0137] .

[0034] Methacrylic resins containing pentadienylimine structural units (B-3) may also include aromatic vinyl monomer units as needed. There are no particular limitations on the aromatic vinyl monomers, and examples include styrene and α-methylstyrene, with styrene being preferred.

[0035] The lactone ring structural unit (B-4) constituting the above-mentioned methacrylic acid resin can be formed after resin polymerization. As the (B-4) structural unit, the structural unit represented by the following general formula (5) is suitable. [Chemical 5] In the above general formula (5), R1, R2, and R3 independently represent hydrogen atoms or organic groups with 1 to 20 carbon atoms. Furthermore, the organic group may also contain oxygen atoms. The above-mentioned lactone ring structural unit (B-4) can be used alone or in combination of two or more.

[0036] The lactone ring structural unit can be formed, for example, by copolymerizing an acrylic monomer with hydroxyl groups with a methacrylate monomer such as methyl methacrylate, introducing hydroxyl groups, ester groups or carboxyl groups into the molecular chain, and then causing the hydroxyl groups and ester groups or carboxyl groups to undergo de-alcoholization (esterification) or dehydration condensation (hereinafter also referred to as "cyclization condensation reaction") to form the unit.

[0037] Examples of acrylic monomers with hydroxyl groups used for polymerization include 2-hydroxymethylacrylic acid, 2-hydroxyethylacrylic acid, alkyl 2-hydroxymethylacrylic acid, alkyl 2-hydroxyethylacrylic acid, etc., with methyl 2-hydroxymethylacrylic acid and ethyl 2-hydroxymethylacrylic acid being more preferred.

[0038] When the methacrylic resin is set to 100% by mass, the content of the lactone ring structural unit (B-4) is preferably 1 to 70% by mass, more preferably 3 to 60% by mass, and even more preferably 5 to 40% by mass. If the content of the lactone ring structural unit (B-4) is within the above range, it is preferable to obtain a resin with good molding processability, heat resistance, optical properties, low birefringence, solvent resistance, and surface hardness.

[0039] Methacrylic resins containing lactone ring structural units (B-4) may also include aromatic vinyl monomer units as needed. There are no particular limitations on the aromatic vinyl monomers, and examples include styrene and α-methylstyrene, with styrene being preferred.

[0040] As the anhydride structural unit (B-5) constituting the above-mentioned methacrylic resin, for example, anhydrides such as maleic anhydride, half-esters of the anhydride and straight-chain or branched alcohols having 1 to 20 carbon atoms, or α,β-vinyl unsaturated carboxylic acids can be used.

[0041] When the methacrylic resin is set to 100% by mass, the content of the anhydride structural unit (B-5) is preferably 1 to 70% by mass, more preferably 3 to 60% by mass, and even more preferably 5 to 40% by mass. If the content of the anhydride structural unit (B-5) is within the above range, it is preferable to obtain a resin with good processability, heat resistance, optical properties, and low birefringence.

[0042] The methacrylic resin containing the anhydride structural unit (B-5) may also include, as needed, structural units from other monomers that can copolymerize with the methacrylate monomer unit (A) and the anhydride structural unit (B-5).

[0043] As an aromatic vinyl monomer, there is no particular limitation, and examples include styrene, α-methylstyrene, etc., with styrene being preferred. As an unsaturated nitrile monomer, there is no particular limitation, and examples include acrylonitrile, methacrylonitrile, ethylacrylonitrile, etc., with acrylonitrile being preferred.

[0044] As the aromatic structural unit (B-6) constituting the above-mentioned methacrylic resin, the structure represented by the following general formula (6) is suitable. [Chemical 6] In the above general formula (6), R1 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, which may, for example, be substituted with a hydroxyl group. R2 is selected from any one of the group consisting of a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an aryl group having 6 to 8 carbon atoms, and an aryloxy group having 6 to 8 carbon atoms. R2 may be the same group or different groups. Furthermore, R2 may also form a ring structure with each other. In general formula (6), n represents an integer from 0 to 5.

[0045] Specific examples of the monomers represented by the above general formula (6) are not particularly limited, and examples include: styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, 2,4-dimethylstyrene, 2,5-dimethylstyrene, 3,4-dimethylstyrene, 3,5-dimethylstyrene, p-ethylstyrene, m-ethylstyrene, o-ethylstyrene, p-tert-butylstyrene, 1-vinylnaphthalene, 2-vinylnaphthalene, 1,1-diphenylstyrene, isopropenylbenzene (α-methylstyrene), isopropenyltoluene, isopropenylethylbenzene, isopropenylpropylbenzene, isopropenylbutylbenzene, isopropenylpentylbenzene, isopropenylhexylbenzene, isopropenyloctylbenzene, etc. Among the above, styrene and α-methylstyrene are preferred. From the viewpoint of improving fluidity or reducing unreacted monomers due to increased polymerization conversion, styrene is more preferred.

[0046] When the methacrylic resin is set to 100% by mass, the content of aromatic structural unit (B-6) is preferably 1 to 30% by mass, more preferably 3 to 25% by mass, and even more preferably 5 to 20% by mass. If the content of aromatic structural unit (B-6) is within the above range, it is preferable to obtain a resin with good molding processability, heat resistance, optical properties, and low birefringence.

[0047] As the alicyclic structural unit (B-7) constituting the above-mentioned methacrylic resin, a saturated alicyclic hydrocarbon compound having vinyl groups is suitable.

[0048] From the viewpoint of mechanical strength, heat resistance and formability, the number of carbon atoms constituting the alicyclic structure is usually in the range of 4 to 30, preferably 5 to 20, more preferably 5 to 15, and most preferably 6.

[0049] Specific examples of such monomers include: vinylcyclohexane, isopropenylcyclohexane, 4-methylisopropenylcyclohexane, 3-methylisopropenylcyclohexane, 4-methylvinylcyclohexane, 3-methylvinylcyclohexane, etc.

[0050] This structural unit can be formed, for example, by copolymerizing a vinylcycloalkane monomer with a methacrylate monomer such as methyl methacrylate. Alternatively, it can be formed by copolymerizing a vinylcycloolefin monomer or an aromatic vinyl monomer with a methacrylate monomer such as methyl methacrylate, introducing an unsaturated alicyclic group or aromatic ring into the molecular chain, and then hydrogenating it. In the hydrogenation reaction, it is preferable to hydrogenate at least 80% of all carbon-carbon unsaturated bonds containing the aromatic ring, more preferably at least 95%, and even more preferably 99-100%.

[0051] Examples of vinyl cycloolefin monomers used for polymerization include: 4-vinylcyclohexene, 4-isopropenylcyclohexene, 1-methyl-4-vinylcyclohexene, 2-methyl-4-vinylcyclohexene, 1-methyl-4-isopropenylcyclohexene, 2-methyl-4-isopropenylcyclohexene, etc.

[0052] Examples of aromatic vinyl monomers used for polymerization include: styrene, α-methylstyrene, α-ethylstyrene, α-propylstyrene, α-isopropylstyrene, α-tert-butylstyrene, 2-methylstyrene, 3-methylstyrene, 4-methylstyrene, 2,4-diisopropylstyrene, 2,4-dimethylstyrene, 4-tert-butylstyrene, 5-tert-butyl-2-methylstyrene, 4-monochlorostyrene, dichlorostyrene, 4-monofluorostyrene, 4-phenylstyrene, etc.

[0053] When the methacrylic resin is set to 100% by mass, the content of the alicyclic structural unit (B-7) is preferably 1 to 70% by mass, more preferably 3 to 60% by mass, and even more preferably 5 to 40% by mass. If the content of the alicyclic structural unit (B-7) is within the above range, it is preferable to obtain a resin with good processability, heat resistance, optical properties, and low birefringence.

[0054] Examples of other vinyl monomer units (C) that can be copolymerized with methacrylate monomer units include: acrylate monomer units (C-1), cyanoethylene monomer units (C-2), and monomer units other than these (C-3). The other vinyl monomer units (C) that can be copolymerized with methacrylate monomers may be used alone or in combination with two or more.

[0055] The monomer unit (C) above can be selected from suitable materials according to the characteristics required by the methacrylic resin of this embodiment. In cases where thermal stability, flowability, mechanical properties, chemical resistance and other properties are particularly required, it is more suitable to select at least one of the group consisting of acrylate monomer unit (C-1) and vinyl cyanide monomer unit (C-2).

[0056] As the acrylate structural unit (C-1) constituting the above-mentioned methacrylic resin, the structural unit represented by the following general formula (7) is suitable. [Chemical 7] In the above general formula (7), R1 represents a hydrogen atom or an alkoxy group having 1 to 12 carbon atoms, and R2 represents an alkyl group having 1 to 18 carbon atoms.

[0057] From the viewpoint of improving the weather resistance, heat resistance, flowability, and thermal stability of the methacrylic resin of this embodiment, the monomers used to form the above-mentioned acrylate monomer unit (C-1) are preferably methyl acrylate, ethyl acrylate, n-propyl acrylate, n-butyl acrylate, dibutyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, phenyl acrylate, etc., and more preferably methyl acrylate, ethyl acrylate, and n-butyl acrylate. From the viewpoint of ease of acquisition, methyl acrylate and ethyl acrylate are even more preferred. The above-mentioned acrylate monomer unit (C-1) may be used alone or in combination with two or more types.

[0058] When using acrylate monomer units (C-1), from the viewpoint of heat resistance and thermal stability, when the total amount of (A) monomer units and (B) structural units is set to 100% by mass, it is preferably 5% by mass or less, and more preferably 3% by mass or less.

[0059] The monomer constituting the cyanoethylene monomer unit (C-2) of the above-mentioned methacrylic acid resin is not particularly limited, and examples include acrylonitrile, methacrylonitrile, and dicyandioxide. Among these, acrylonitrile is preferred from the viewpoint of ease of acquisition and chemical resistance. The above-mentioned cyanoethylene monomer unit (C-2) may be used alone or in combination with two or more types.

[0060] In the case of using cyanide monomer unit (C-2), from the viewpoint of maintaining solvent resistance and heat resistance, when the total amount of (A) monomer unit and (B) structural unit is set to 100% by mass, it is preferably 15% by mass or less, more preferably 12% by mass or less, and even more preferably 10% by mass or less.

[0061] There is no particular limitation on the monomers (C-3) that constitute the monomer units other than (C-1) and (C-2) of the above-mentioned methacrylic resins. Examples include: acrylamide, methacrylamide and other amides; ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate and other monomers obtained by esterifying the two terminal hydroxyl groups of ethylene glycol or its oligomers with acrylic acid or methacrylic acid; neopentyl glycol di(meth)acrylate, di(meth)acrylate and other monomers obtained by esterifying the hydroxyl groups of two alcohols with acrylic acid or methacrylic acid; trimethylolpropane, neopentyl tetraol and other monomers obtained by esterifying polyol derivatives with acrylic acid or methacrylic acid; divinylbenzene and other multifunctional monomers.

[0062] The content of other vinyl monomer units (C) that can be copolymerized with methacrylate monomers, which is set as 100% by mass, is 0 to 20% by mass, more preferably 0 to 18% by mass, and even more preferably 0 to 15% by mass, from the viewpoint of improving the heat resistance imparted by the (B) structural unit. In particular, when using a polyfunctional (meth)acrylate with crosslinking properties having a plurality of reactive double bonds as the (C) monomer unit, the content of the (C) monomer unit is preferably 0.5% by mass or less, more preferably 0.3% by mass or less, and even more preferably 0.2% by mass or less, from the viewpoint of polymer flowability.

[0063] The stereoregularity of the above-mentioned methacrylic resins is not specifically limited to ternary representation of syndiotacticity (rr) and atacticity (mr). Syndiotacticity (rr) is the ratio of two racemic chains (diad) in a tripartite (triad). Similarly, atacticity (mr) is the ratio of meso and racemic chains (diad) in a tripartite (triad). Furthermore, in polymer molecules, chains with the same stereoconfiguration are called meso, and those with different stereoconfigurations are called racemo, denoted as m and r respectively.

[0064] The ternary representation of the syndiotactic (rr) ratio and the random (mr) ratio was obtained by measuring 1H-NMR spectra in deuterated chloroform at 30°C. In this spectrum, with TMS set to 0 ppm, the chemical shifts corresponding to syndiotactic (rr) were observed in the range of 0.6–0.95 ppm, and the chemical shifts corresponding to random (mr) were observed in the range of 0.95–1.10 ppm. The ratio of the peak areas to the area of ​​the region from 0.6 to 1.35 ppm is called the syndiotactic (rr) ratio and the random (mr) ratio.

[0065] (Other components) When using thermoplastic resin as the material constituting the resin substrate of this embodiment, other known resins may also be combined, as long as they can perform the properties required for the resin substrate of this embodiment and the resin optical element.

[0066] Other resins are not limited to the following, but may include, for example: rubbery polymers such as acrylic rubber, polyethylene resins, polypropylene resins, polystyrene resins, para-polystyrene resins, polycarbonate resins, ABS resins, acrylic resins, AS resins, BAAS resins, MBS resins, AAS resins, biodegradable resins, polyurethane resins, alloys of polycarbonate-ABS resins, polyalkylene alkyl ester resins (polybutylene terephthalate, polyethylene terephthalate, polypropylene terephthalate, polytrimethylene terephthalate, polyethylene naphthalate, etc.), polyamide resins, polyphenylene ether resins, polyphenylene sulfide resins, phenolic resins, etc. Each of the above thermoplastic resins may be used alone or in combination of two or more resins.

[0067] In particular, when used in combination with methacrylic resins, AS resins and BAAS resins are preferable from the viewpoint of improved flowability; acrylic rubber polymers, ABS resins, and MBS resins are preferable from the viewpoint of improved impact resistance; and polyester resins are preferable from the viewpoint of improved chemical resistance. Polycarbonate resins are preferable when heat resistance, impact resistance, or optical properties need to be imparted. Furthermore, acrylic resins have good compatibility with the aforementioned methacrylic resins, and are preferable when adjusting flowability, impact resistance, and other properties while maintaining transparency.

[0068] When combining the thermoplastic resin with the other resins used in this embodiment, the combination should be within the range that enables the effects of the present invention to be demonstrated. Considering the effect of imparting properties, the mixing ratio of the other resins relative to 100% by mass of the total mass of the thermoplastic resin and the other resins is preferably 50% by mass or less, more preferably 45% by mass or less, further preferably 40% by mass or less, further preferably 30% by mass or less, and most preferably 20% by mass or less. Furthermore, considering the effect of imparting properties when mixing other resins, the lower limit of the mixing amount when mixing other resins is preferably 0.1% by mass or more, more preferably 1% by mass or more, further preferably 2% by mass or more, further preferably 3% by mass or more, and most preferably 5% by mass or more. The type or content of the other resins can be appropriately selected according to the desired effect when used in combination with other resins.

[0069] (Additives) When using thermoplastic resin in this embodiment, additives may be selectively formulated at will. There are no particular limitations on the additives as long as they can achieve the effects of the present invention, and they can be appropriately selected according to the purpose.

[0070] As an additive, it is not limited to the following, but may include: various stabilizers such as ultraviolet absorbers, heat stabilizers, and light stabilizers; release agents; lubricants; plasticizers; flame retardants; flame retardant additives; hardeners; hardening accelerators; antistatic agents; conductivity imparting agents; stress relievers; crystallization accelerators; hydrolysis inhibitors; chain length extenders; compatibilizers; nucleating agents; reinforcing materials such as fillers; impact imparting agents; flow modifiers; dyes; sensitizers; colorants; tackifiers; precipitation inhibitors; anti-sagging agents; filler materials; defoamers; coupling agents; light diffusing microparticles; refractive index modifiers; linear heat absorbers; rust inhibitors; antibacterial agents; mildew inhibitors; antifouling agents; conductive polymers, etc.

[0071] The above-mentioned resin substrate may also be a thermosetting resin or an active energy-curing resin.

[0072] When using the above-mentioned thermosetting resins and / or active energy-curing resins, examples include: (meth)acrylate resins, epoxy resins, silicone resins, aliphatic allyl carbonate resins, aromatic allyl carbonate resins, polyurethane resins, polythiocarbamate resins, cyclosulfide resins, polyurea resins, etc. Furthermore, antioxidants, ultraviolet absorbers, specific wavelength absorbing materials, release agents, curing agents, molecular weight modifiers, photochromic agents, etc., may be added as needed, within a range that does not impair the effects of the present invention.

[0073] <Moisture-proof layer> The moisture-proof layer in this embodiment is an amorphous film containing aluminum, silicon, oxygen, and carbon. If the moisture-proof layer is polycrystalline as disclosed in Patent Document 1, gas can pass through continuous paths containing the grain boundaries of polycrystalline materials or the chaotic voids near the grain boundaries, columnar structures, etc. Therefore, it is impossible to obtain a higher moisture-proof effect that can withstand long-term storage in high-temperature and high-humidity environments. By making the moisture-proof layer an amorphous film, there are no continuous paths for gas to pass through. Therefore, the gas permeation rate in the moisture-proof layer is suppressed, and a higher moisture-proof effect that can withstand long-term storage in high-temperature and high-humidity environments can be obtained, which can impart higher shape stability and optical performance stability.

[0074] Furthermore, the moisture-proof layer of this embodiment may also have pores inside. When pores exist inside the moisture-proof layer, although the moisture-proof effect of the moisture-proof layer will be reduced, the flexibility of the moisture-proof layer will be improved, and the shape stability and optical property stability under high temperature and high humidity environments will be improved. Therefore, the effect of this embodiment can be achieved by appropriately determining the balance between the dispersion state of the pores and the thickness of the moisture-proof layer. The number or size of the pores and the dispersion state are determined by the amount of unreacted components of the raw material gas in the moisture-proof film, or the amount of gas generated by the resin substrate, etc. Therefore, the pores can be controlled by appropriately setting and implementing the film-forming conditions of the moisture-proof film including the vacuum degree of the chamber, or by pre-treating the resin substrate (gas discharge), etc. When pores exist inside the moisture-proof layer, the number of pores is preferably an appropriate number that will not significantly impair the moisture-proof effect and optical properties of the moisture-proof layer. In addition, the size of the pores is preferably smaller than the thickness of each layer constituting the moisture-proof layer, and the structure is discontinuous. If the pores, due to their size or connectivity, form a continuous moisture-proof layer, capillary action will promote flow, thereby significantly impairing the moisture-proof effect. Furthermore, in order to suppress light scattering within the pores, the pore size is preferably sufficiently smaller than the wavelength used in the optical molded article.

[0075] Preferably, the aforementioned moisture-proof layer further contains nitrogen. Furthermore, the aforementioned moisture-proof layer is preferably an alternating layer structure of an aluminum-based composition layer containing aluminum, oxygen, and carbon, with the total content of aluminum, oxygen, and carbon being 70 atomic% or more, and a silicon-based composition layer containing silicon, oxygen, and nitrogen, with the total content of silicon, oxygen, and nitrogen being 70 atomic% or more. The total content of aluminum, oxygen, and carbon in the aluminum-based composition layer is preferably 70 atomic% or more, more preferably 75 atomic% or more, further preferably 80 atomic% or more, and particularly preferably 85 atomic% or more. It is also preferably 99.5 atomic% or less, more preferably 99 atomic% or less, and further preferably 98.5 atomic% or less. By making the composition of the aluminum-based composition layer at or above the aforementioned lower limit, excellent shape stability and optical performance stability under high temperature and high humidity environments are achieved. Furthermore, by setting the composition of the aluminum-based layer to the upper limit mentioned above, the flexibility of the moisture-proof layer is improved, resulting in excellent suppression of cracking in the moisture-proof layer and optical functional layer under high temperature and high humidity environments. The total content of silicon, oxygen, and nitrogen in the silicon-based layer is preferably 70 atomic% or more, more preferably 75 atomic% or more, and even more preferably 80 atomic% or more. It is also preferably 99.5 atomic% or less, more preferably 99 atomic% or less, even more preferably 98 atomic% or less, even more preferably 97 atomic% or less, and particularly preferably 96 atomic% or less. By setting the composition of the silicon-based layer to the lower limit mentioned above, excellent shape stability and optical performance stability are achieved under high temperature and high humidity environments. Furthermore, by setting the composition of the silicon-based layer to the upper limit mentioned above, the flexibility of the moisture-proof layer is improved, resulting in excellent suppression of cracking in the moisture-proof layer and optical functional layer under high temperature and high humidity environments.

[0076] In the aforementioned moisture-proof layer, it is preferable that the element with the largest proportion in the aluminum-based composition layer is oxygen, and the second largest element is aluminum. Also, it is preferable that the element with the largest proportion in the aforementioned silicon-based composition layer is oxygen, and the second largest element is silicon. By making the aforementioned moisture-proof layer have the above composition, each layer of the moisture-proof layer has sufficient moisture-proof performance, and the moisture-proof layer as a whole can exhibit high moisture-proof performance, thus exhibiting high shape stability and optical performance stability.

[0077] In the aforementioned moisture-proof layer, the ratio of the total thickness of the aluminum-based component layer to the total thickness of the silicon-based component layer (aluminum-based component layer: silicon-based component layer) is preferably 1:4 to 4:1, more preferably 1:3 to 3:1, and even more preferably 1:2 to 2:1. Thin films generally containing inorganic compounds have film stress. The aluminum-based component layer has tensile stress, and the silicon-based component layer has compressive stress. If the ratio of the total thickness of the aluminum-based component layer to the silicon-based component layer is within the aforementioned range, the film stress is appropriately offset, and the overall film stress of the moisture-proof layer is reduced, which is therefore preferable. The reduction in the overall film stress of the moisture-proof layer is preferable from the viewpoint of suppressing substrate deformation caused by the film-forming moisture-proof layer and from the viewpoint of good adhesion between the moisture-proof layer and the substrate layer.

[0078] The total number of layers in the above-described alternating laminated structure is preferably 6 or more. If the moisture-proof layer is a single-layer structure, cracks may occur when the moisture-proof layer cannot keep up with the expansion of the resin substrate under high temperature and high humidity conditions. In this case, gas flows through the continuous path including the continuous cracks, and the capillary flow within the cracks promotes flow, resulting in a significant reduction in the moisture-proof effect of the moisture-proof layer. On the other hand, by making the moisture-proof layer a laminated structure, even if cracks occur in a portion of the laminated structure, the cracking will stop at the interface of the laminated structure and will not penetrate the entire moisture-proof layer. Therefore, it is possible to maintain a high moisture-proof effect of the moisture-proof layer as a whole without generating continuous paths including cracks. Furthermore, in this embodiment, a rigid optical functional layer with low flexibility is formed on the moisture-proof layer. The alternating laminated structure of the moisture-proof layer also has the following effect: it efficiently disperses the stress generated between the substrate with a high expansion rate under high temperature and high humidity conditions and the rigid optical functional layer with a low expansion rate. Regarding the effect of suppressing the generation of penetrating cracks and dispersing stress, the more layers there are, the greater the effect. The total number of layers is preferably 8 or more, more preferably 10 or more, especially 12 or more, and even more preferably 14 or more. Furthermore, from the viewpoint of productivity and uniformity of membrane structure, it is preferable to have 100 or fewer layers, more preferably 80 or fewer, even more preferably 60 or fewer, and particularly preferably 50 or fewer.

[0079] Preferably, the moisture-proof layer is applied to the entire surface of the molded article. Furthermore, the film thickness distribution of the moisture-proof layer is preferably within 10%. In cases where the moisture-proof layer is defective, has non-film-forming portions, or its thickness results in areas with lower moisture-proof performance, the following situation arises: moisture absorption occurs unevenly from these areas, leading to a decrease in the overall shape accuracy of the optical element.

[0080] When the aforementioned moisture-proof layer reaches the outermost surface of the optical molded article, the outermost surface is preferably a silicon-based composite layer. Silicon-based composite layers have relatively high surface hardness and low reactivity with components or moisture in the air, thus enabling them to maintain a stable film over a long period. To protect the moisture-proof layer and the resin substrate, the outermost silicon-based composite layer is preferably at least as thick as the silicon-based composite layer inside the moisture-proof layer.

[0081] The above-mentioned moisture-proof layer can be formed by known methods. From the viewpoint of obtaining a uniformly composed amorphous form and uniformly covering the entire surface of the molded article, it is preferable to form the film by chemical vapor deposition, and even more preferably by atomic layer deposition (ALD).

[0082] A known device may be used for performing ALD.

[0083] The raw material gas (precursor) used in ALD may be a known compound.

[0084] Examples of the above-mentioned raw material gases include organometallic raw materials, and more specifically, examples include: organosilicon with Si-O bonds or Si-C bonds, raw material gases containing metal-oxygen bonds or metal-carbon bonds, organometallic complexes, or silicon or metal hydrides. More specifically, examples of reactant gases include: silanes (a general term for hydrogenated silanes), TEOS (TetraEthyl OrthoSillicate), TMS (TriMethoxySilane), TES (TriEthoxySilane), TMA (TriMethyl Alminium), DMAI (DiMethylAluminum Isopropoxide), TDMAS (Tris(DiMethylAmino)Silane), BDEAS (Bis(DiEthylAmino)Silane), BTBAS (Bis(Tertiary-ButylAmino)Silane), etc., or Orthrus (a registered trademark of Air Liquide). Furthermore, examples can be given of heterogeneous complexes containing multiple metallic elements rather than a single metallic element.

[0085] Examples of oxidizing gases used in ALD include oxygen, water (water vapor), ozone, ammonia, and nitrogen. Furthermore, the raw material gas and oxidizing gas can also be supplied to the reaction chamber of the ALD film-forming apparatus using carrier gases (N2, Ar, He, etc.).

[0086] The aforementioned moisture-proof layer can be formed by thermal ALD (thermal ALD) using heat-promoted chemical reaction or PE-ALD (Plasma-Enhanced ALD) using plasma-promoted chemical reaction. From the viewpoint of suppressing damage to the substrate during film formation and obtaining a moisture-proof layer with good adhesion, and from the viewpoint of easily adjusting the composition to a suitable range, minimizing the deterioration of moisture-proof performance under high temperature and high humidity environments, and obtaining optical elements with higher shape stability and performance stability, it is preferable to use an organometallic raw material as the raw gas and ozone gas as the reactant gas to form a layer by thermal ALD.

[0087] The composition, structure, and film thickness uniformity obtained by ALD vary depending on various parameters such as the type of raw material gas or oxidizing gas, gas flow rate, pulse time, film formation temperature, and pressure. For example, these parameters can be controlled. By appropriately setting these parameters, a moisture-proof film with the specified composition, structure, and film thickness uniformity in this embodiment can be obtained. Film formation temperature: The content ratio of aluminum, silicon, oxygen, carbon, and nitrogen varies depending on the film formation temperature. Depending on the adsorption state or reactivity of the raw material gas during the supply stage, the content may increase or decrease. When considering the adsorption state of the raw material gas, for example, when the raw material gas is physically adsorbed onto the film formation surface and undergoes a condensation reaction, setting the film formation temperature higher results in greater kinetic energy of the raw material gas and lower influence of physical adsorption. Therefore, unreacted components are less likely to remain, and the content of aluminum, silicon, and oxygen is higher. On the other hand, when the adsorption of the feed gas on the film surface is incomplete, setting the film-forming temperature higher facilitates the adsorption reaction. However, depending on the structure of the feed gas, aggregation reactions as described above may sometimes occur, reducing the content of aluminum, silicon, and oxygen. Setting the film-forming temperature too high may sometimes promote the detachment of the adsorbed gas, resulting in poor film thickness uniformity. Furthermore, considering the reactivity of the feed gas, generally speaking, the higher the temperature, the higher the reactivity, and therefore, the higher the content of aluminum and silicon. From a structural point of view, at higher temperatures, the molecules forming the film more easily move to their restatement positions (on the crystal lattice). Therefore, amorphous films are more likely to form at lower film-forming temperatures, while crystalline films are more likely to form at higher temperatures. Selection of feed gas: The higher the reactivity of the feed gas, the less likely unreacted components will remain; therefore, the higher the content of aluminum, silicon, and oxygen. Raw material gas venting time: The shorter the venting time of the raw material gas, the greater the impact of unreacted component residue due to the physical adsorption of the raw material gas, resulting in lower aluminum, silicon, and oxygen content. Oxidizing gas selection: Using a more reactive oxidizing gas promotes the reaction, increasing the aluminum, silicon, and oxygen content. Oxidizing gas concentration: Setting a higher oxidizing gas concentration promotes the reaction, increasing the aluminum, silicon, and oxygen content. Furthermore, film thickness uniformity improves. Oxidizing gas pulse time: The longer the oxidizing gas flow time, the more it promotes the reaction, resulting in higher aluminum, silicon, and oxygen content. Furthermore, film thickness uniformity improves. Oxidizing gas lifetime: When using a gas with a short lifetime (active species) as the oxidizing gas, the oxidizing gas deactivates before covering the entire surface of the molded product, easily leaving unreacted raw material gas residue. Therefore, the aluminum, silicon, and oxygen content decreases. Furthermore, film thickness uniformity decreases. Vacuum level during exhaust: If the vacuum level during exhaust is low (pressure is high), the exhaust of raw material gas or oxidizing gas is not fully carried out, the influence of unreacted components becomes greater, and the content of aluminum, silicon, and oxygen decreases. In addition, the lower the content of aluminum, silicon, and oxygen in the obtained film, the easier it is to form an amorphous film.

[0088] The film-forming temperature of the ALD is preferably performed at a higher temperature within a range that does not cause deterioration or deformation of the substrate. Here, the film-forming temperature refers to the temperature of the inner wall of the cavity into which the substrate is immersed during film formation. The heating of the substrate is mainly carried out by radiant heat from the inner wall of the cavity; therefore, the substrate temperature is usually about 20°C lower than the inner wall temperature of the cavity. The film-forming temperature is preferably set such that the substrate temperature is 30°C or higher than the temperature at which the reliability test is conducted, and more preferably, it is set such that the substrate temperature is higher than or equal to the temperature at which the reliability test is conducted. Specifically, the film-forming temperature is preferably 60°C or higher, more preferably 70°C or higher, more preferably 80°C or higher, and especially preferably 90°C or higher. When considering the difference in expansion rates between the substrate and the moisture-proof layer, the reference temperature at which the strain between the two becomes zero is near the substrate temperature during film formation. Therefore, by forming the film at a temperature above the reliability test temperature, the difference in expansion rates between the substrate and the moisture-proof layer during the reliability test is reduced, and the effectiveness of the moisture-proof layer as a buffer layer is enhanced. This suppresses the formation of cracks caused by the difference in expansion rates between the substrate, the moisture-proof layer, and the optical functional layer. On the other hand, from the viewpoint of suppressing cracking in low-temperature regions below -30°C caused by substrate deformation due to the decomposition of raw material gases or film stress, or by the difference in shrinkage rates between the substrate, the moisture-proof layer, and the optical functional layer, and also from the viewpoint of suppressing the formation of crystalline phases and obtaining an amorphous film with excellent moisture-proof performance and flexibility, the film-forming temperature is preferably 150°C or lower, more preferably 140°C or lower, further preferably 130°C or lower, and particularly preferably 120°C or lower.

[0089] The thickness of each layer of the aforementioned moisture-proof layer is not particularly limited, but is preferably 1 nm or more, more preferably 2 nm or more, and even more preferably 5 nm or more. Furthermore, it is preferably 50 nm or less, more preferably 30 nm or less, even more preferably 20 nm or less, even more preferably 15 nm or less, and particularly preferably 10 nm or less. If the thickness of each layer is within the above range, it is preferable from the viewpoints of inhibiting film peeling and cracking caused by film stress, or transparency, flexibility, and manufacturability. The thickness of each layer may be the same, or the thickness of each layer may be different.

[0090] Furthermore, from the viewpoint of suppressing chemical changes in the moisture-proof layer caused by long-term exposure to a constant temperature and humidity environment and maintaining good moisture-proof performance over a long period, the outermost layer of the moisture-proof layer (the layer furthest from the resin substrate) is preferably a silicone-based layer. This silicone-based layer may have the same thickness as the silicone-based layer located further inside (closer to the resin substrate), or it may have a different thickness, but it is preferably a thickness greater than that of the inner silicone-based layer. When different thicknesses are used, from the viewpoint of improving the protective properties of the moisture-proof film, it is preferably 5 nm or more, more preferably 10 nm or more, and even more preferably 15 nm or more, and most preferably 20 nm or more. On the other hand, from the viewpoint of crack suppression and productivity, it is preferably 100 nm or less, more preferably 50 nm or less, and even more preferably 30 nm or less.

[0091] Furthermore, from the viewpoint of the moisture-proof performance of the layer itself, the total thickness of the moisture-proof layer is preferably 20 nm or more, more preferably 30 nm or more, and even more preferably 50 nm or more, and even more preferably 60 nm or more. Furthermore, from the viewpoint of productivity, and from the viewpoint of maintaining good overall flexibility of the moisture-proof layer and suppressing cracking, it is preferably 200 nm or less, more preferably 150 nm or less, even more preferably 120 nm or less, and even more preferably 100 nm or less.

[0092] <Aluminum-based constituent layer> From the viewpoint of the layer's flexibility and crack resistance, the carbon content in the aforementioned aluminum-based constituent layer is preferably 0.1 atomic% or more, more preferably 1 atomic% or more, further preferably 2 atomic% or more, and particularly preferably 3 atomic% or more. Furthermore, from the viewpoint of the layer's moisture resistance, it is preferably 10 atomic% or less, more preferably 9 atomic% or less, and further preferably 8 atomic% or less. If the carbon content is within this range, it is preferable from the viewpoint of balancing the layer's moisture resistance, flexibility, and crack resistance. Furthermore, if the carbon content is within this range, it is preferable from the viewpoint of easily obtaining an amorphous film at film-forming temperatures below the heat resistance temperature (approximately 150°C or less) of the resin-based substrate.

[0093] Furthermore, the aforementioned aluminum-based constituent layer may also contain other atoms besides aluminum, oxygen, and carbon. For example, it may also contain nitrogen or silicon. When other atoms are included, the content of each atom is preferably less than the content of aluminum atoms in the aluminum-based constituent layer.

[0094] <Silicone-based constituent layer> From the viewpoint of the layer's flexibility and crack resistance, the nitrogen content in the aforementioned silicon-based constituent layer is preferably 0.1 atomic% or more, more preferably 0.2 atomic% or more, and even more preferably 0.4 atomic% or more. Furthermore, from the viewpoint of the layer's moisture resistance, it is preferably 10 atomic% or less, more preferably 8 atomic% or less, even more preferably 6 atomic% or less, and particularly preferably 4 atomic% or less. If the nitrogen content is within this range, it is preferable from the viewpoint of balancing the layer's moisture resistance, flexibility, and crack resistance. Furthermore, if the nitrogen content is within this range, it is preferable from the viewpoint of easily obtaining an amorphous film at film-forming temperatures below the heat resistance temperature (approximately 150°C or less) of the resin substrate.

[0095] Furthermore, the aforementioned silicon-based constituent layer may also contain other atoms besides silicon, oxygen, and nitrogen. For example, it may also contain carbon or aluminum. When other atoms are included, the content of each atom is preferably less than the content of silicon atoms in the silicon-based constituent layer.

[0096] <Optical Functional Layer> The optical functional layer in this embodiment is an anti-reflective film and / or a partially reflective film.

[0097] The so-called anti-reflection film refers to an optical functional layer that has the function of reducing the surface reflectivity of incident light. As a typical example, a layer with a spectral reflectivity of less than 1% in the visible light wavelength region (400-700 nm) can be cited. The wavelength range or the value of spectral reflectivity can be appropriately set according to the application of the optical molded body.

[0098] A partial reflective film refers to an optical functional layer that has the function of reflecting a portion of the incident light and transmitting a portion of it. As a typical example, a half mirror with a spectral reflectance of 50% ± 5% in the visible light wavelength region (400–700 nm) can be cited. The wavelength range or the value of the spectral reflectance can be appropriately set according to the application of the optical molded body.

[0099] The optical functional layer of this embodiment can be formed by known methods. For example, vacuum evaporation, sputtering, ion plating, immersion, inkjet printing, etc. can be suitably used.

[0100] The optical functional layer of this embodiment can be composed of dielectric single-layer film, dielectric multilayer film, metal film, thermosetting resin, active energy line curing resin, etc. Alternatively, a moth-eye structure with a continuously changing refractive index from the side near the moisture-proof layer to the air layer can also be used.

[0101] The optical functional layer can cover the entire surface of the optical molded body, or it can cover only the part through which light passes. Furthermore, in the case of multiple optically effective surfaces, the film can be formed on any one surface or multiple surfaces.

[0102] Furthermore, the optical functional layer may also have other optical functional layers while having an anti-reflective film and / or a partial reflective film. As an example, high reflectivity (mirror) characteristics can be cited, and further, the characteristics of bandpass filters, cutoff filters, dichroic filters, grooved filters, etc.

[0103] <Articles Using Optical Molded Bodies> The optical molded body of this embodiment can be used in combination with a housing as needed, or it can be the housing itself. Furthermore, it can also be used with protective films, optical films, or other films.

[0104] The optical molded body of this embodiment can be used as an optical element and is suitable for use in optical parts in household products, office automation equipment, audio-visual equipment, batteries and electrical parts, lighting equipment, automobile parts, etc.

[0105] As a suitable example, the lens of a VR (Virtual Reality) head-mounted display (HMD) can be cited. Head-mounted displays are image display devices worn on the head, so they need to be small, lightweight, and cause little discomfort when worn. As a method of miniaturization, a method has been proposed that combines a quarter-wave plate and a reflective polarizer with a lens to change the polarization state of the light passing through the lens, switching between reflection and transmission, so that the image travels back and forth once and a half times in a single lens (US Patent No. 6,563,638, Japanese Patent Application Publication No. 2017-21321, etc.).

[0106] The above method is, for example, based on the following mechanism. A quarter-wave plate and a reflective polarizer are disposed on the back of a lens with a partially reflective coating on the front side. Light incident from the front of the lens as circularly polarized light is converted into linearly polarized light by the quarter-wave plate after passing through the lens. This linearly polarized light is reflected by the reflective polarizer, and then converted back into circularly polarized light (opposite to the initial polarization) by the quarter-wave plate and incident on the lens from the back side, reaching the partially reflective coating on the front side. The light reflected by the partially reflective coating and exiting from the back of the lens becomes linearly polarized light (90° different from the initial polarization) by the quarter-wave plate and passes through the reflective polarizer, thus entering the eye as an image. In this way, even in a thin optical module, the magnification is high, resulting in a wide field of view.

[0107] If the polarization state changes during the passage of light through the lens, for example, after passing through the lens once, some light passes through a reflective polarizer, resulting in the lower magnification image overlapping with the higher magnification image, making it difficult to obtain a clear image. Therefore, a lens with low birefringence is required. Furthermore, it is also undesirable for the shape of the lens to change due to humidity changes during use, thereby affecting the imaging performance. Therefore, a lens with low hygroscopicity and high shape stability in high temperature and high humidity environments is required.

[0108] Examples of other suitable optical elements for use with the molded body of this embodiment include optical elements in household goods, office automation equipment, audio-visual equipment, batteries and electrical parts, lighting equipment, etc. Examples include: light guide plates, display front panels, and touch panels for displays of smartphones, PDAs, tablet PCs, LCD TVs, etc.; lenses for smartphone and tablet PC cameras, or lenses or prisms for telescopes (periscope cameras) in folding optical systems; and near-infrared sensors (LiDAR; Light Detection) for VR (virtual reality) / AR (augmented reality) / MR (mixed reality) / XR (cross-realization) head-mounted displays or LCD projectors. Optical components such as those from Ranging (Guangda), including prism elements, waveguides, freeform light guides, lenses, especially small, thin-walled optical lenses with uneven thickness; optical fibers, optical fiber coating materials, lenses or prisms for optical communication, lenses, Fresnel lenses, phase plates with microlens arrays, optical cover components, substrates constituting polarization separation elements, polarizing elements, retardation films or substrates bonded to them, lenses, etc.

[0109] As optical components in automotive parts, examples include: light guide plates for automotive displays; optical covers for front panels or including curved shapes used in automotive dashboards, instrument clusters, car navigation systems, information displays, rear-seat displays, etc.; lenses or prisms, light direction conversion elements, waveguides, light guides, combiners, dustproof sheets, optical cover parts, etc. used in head-up displays; automotive camera lenses (especially front lenses); light guide rods, etc.

[0110] As optical components used in aerial displays, examples include: substrates for regressive reflectors or partial transmissive mirrors; optical components with sub-millimeter shapes used to form dihedral reflector arrays; microlens arrays; substrates for concave and convex mirrors; lenses used to magnify or reduce images; and light guide components and direction conversion elements.

[0111] Furthermore, in addition to the above, it can also be preferably used as a display device component for digital signage that transmits information on a thin display connected to the network for purposes such as advertising and promotion in locations such as camera focus plates, outdoor spaces, shops, public institutions, and transportation facilities. [Example]

[0112] Hereinafter, embodiments and comparative examples will be given to specifically describe the content of the present invention. Furthermore, the present invention is not limited to the following embodiments.

[0113] The raw materials used in the manufacturing example are as follows.

[0114] [Monomers] • Methyl methacrylate (MMA): Manufactured by Asahi Kasei Corporation • N-Phenylamyridine (phMI): Manufactured by Nippon Shokubai Corporation • N-Cyclohexylmaleimide (chMI): Manufactured by Nippon Shokubai Corporation

[0115] [Organic Solvent] ・m-Xylene (mXy): Manufactured by Mitsubishi Gas Chemical Co., Ltd.

[0116] [Polymerization Initiator] • 1,1-Di(tert-butylperoxy)cyclohexane: Manufactured by Nippon Oil Co., Ltd., Perhexa C

[0117] [Chain Transfer Agent] • n-Octamethasone: Manufactured by Chevron Phillips Chemical Company

[0118] (Manufacturing Example 1: Methacrylic A Resin) 358.6 kg of methyl methacrylate (MMA), 29.4 kg of N-phenylmaleimide (phMI), 67.7 kg of N-cyclohexylmaleimide (chMI), 0.77 kg of n-octyl mercaptan (as a chain transfer agent), and 224.3 kg of m-xylene (mXy) were weighed and added to a 1.25 m³ reactor equipped with a temperature control device with a sleeve and a stirring blade, and stirred to obtain a mixed monomer solution. Then, 88.0 kg of MMA, 6.3 kg of phMI, and 142.4 kg of mXy were weighed and added to tank 1 and stirred to obtain a top-up mixed monomer solution. Nitrogen gas was introduced into the contents of the reactor at a rate of 30 L / min for 1 hour, and nitrogen gas was introduced into tank 1 at a rate of 10 L / min for 30 minutes to remove dissolved oxygen. Subsequently, steam was blown into the casing to raise the solution temperature in the reactor to 115°C. Stirring was performed at 50 rpm, and simultaneously, a polymerization initiator solution obtained by dissolving 0.470 kg of 1,1-di(tert-butylperoxy)cyclohexane in 1.905 kg of mXy was added at a rate of 1.0 kg / h to initiate polymerization. Furthermore, during polymerization, the solution temperature in the reactor was controlled at 115 ± 2°C using the casing. Thirty minutes after the start of polymerization, the rate of initiator solution addition was reduced to 0.5 kg / h. Then, starting one hour after the start of polymerization, a mixed monomer solution was added in full at a constant rate over a period of four hours. Subsequently, the rate of initiator solution addition was reduced to 0.25 kg / h three and a half hours after the start of polymerization, and addition was stopped five hours after the start of polymerization. Twelve hours after the start of polymerization, a polymer solution containing a methacrylic resin with a cyclic structure in the main chain was obtained, and polymerization was terminated. The polymer solution was fed into a concentration unit containing a tubular heat exchanger preheated to 250°C and a vaporization tank for de-evaporation. The vacuum level in the vaporization tank was set to 10–15 Torr. The resin flowing down from the vaporization tank was extracted by a gear pump, extruded from a wire die, water-cooled, and granulated to obtain methacrylic resin A. The composition of the obtained granular polymer was confirmed, with structural units from MMA, phMI, and chMI monomers accounting for 81.0%, 6.6%, and 12.4% by mass, respectively. Furthermore, the weight-average molecular weight was 108,000, the Mw / Mn ratio was 2.04, and the glass transition temperature was 134°C.

[0119] (Manufacturing Example 2: Methacrylic Acid Resin B) A pentylene-poly(methyl methacrylate) copolymer (8% by mass of styrene) with a molecular weight of 100,000 was used as the raw material. Monomethylamine was used as the amide-iminizing agent. A 15 mm diameter twin-screw extruder was used to manufacture pentylene-amide-iminized resin. The set temperatures of each temperature control zone were set to 230–250 °C, and the screw speed was set to 150 rpm. The methyl methacrylate-styrene copolymer (hereinafter also referred to as "MS resin") was supplied at 2 kg / hr. After the resin was melted and filled by kneading, 8 parts by mass of monomethylamine were injected into the resin through the nozzle. A reverse flight thread was inserted at the end of the reaction zone to fill the resin. The pressure at the vent was reduced to -0.092 MPa to remove reaction byproducts and excess monomethylamine. Resin exiting the extruder nozzle in wire form was cooled in a water bath and then granulated by a granulator to obtain pentyleneiminated MS resin intermediate (1). Subsequently, a 15 mm diameter, co-rotating twin-screw extruder was used. The temperature settings of each temperature control zone were set to 230°C, and the screw speed was 150 rpm. The pentyleneiminated MS resin intermediate (1) obtained from the hopper was fed at a rate of 1 kg / hr. After the resin was melted and filled by kneading, a mixture of 0.8 parts by weight of dimethyl carbonate and 0.2 parts by weight of triethylamine was injected into the resin through the nozzle to reduce the carboxyl groups in the resin. A reverse thread was inserted at the end of the reaction zone to fill the resin. The pressure at the vent was reduced to -0.092 MPa to remove reaction byproducts and excess dimethyl carbonate. Resin exiting the extruder nozzle in filament form is cooled in a water bath and then granulated using a granulator to obtain pentadienoimide MS resin intermediate (2). The pentadienoimide MS resin intermediate (2) is then fed into a 15 mm diameter, co-rotating twin-screw extruder under the following conditions: set temperature of 230°C in each temperature control zone, screw speed of 150 rpm, and feed rate of 1 kg / hr. The pressure at the exhaust port is reduced to -0.095 MPa to further remove unreacted volatiles such as excipients. The devolatileized pentadienoimide resin exiting the extruder nozzle in filament form is cooled in a water bath and then granulated using a granulator to obtain methacrylic resin B (pentadienoimide MS resin). The weight average molecular weight of methacrylic resin B is 85,000, the Mw / Mn ratio is 1.8, and the monomer units in the copolymer are 8% by mass of styrene units, 82% by mass of MMA units, 10% by mass of pentadieneimide units, and the glass transition temperature is 128°C.

[0120] (Manufacturing Example 3: Methacrylic Acid Resin C) In a reaction vessel equipped with a stirrer, temperature sensor, cooling pipe, nitrogen inlet pipe, and drop pump, 5.40 parts by mass of methyl 2-hydroxymethacrylate (hereinafter referred to as RHMA), 37.6 parts by mass of methyl methacrylate (hereinafter referred to as MMA), 0.450 parts by mass of styrene (hereinafter referred to as St), and 90.0 parts by mass of toluene were added. Nitrogen gas was introduced and the temperature was raised to 105°C. A solution containing 3.63 parts by mass of toluene and 0.245 parts by mass of tripentyl peroxyisononanoate was added dropwise as an initial initiator over a period of 9 minutes, while solution polymerization was carried out at 105°C to 110°C. Subsequently, after 11 minutes, a solution containing 4.42 parts by mass of toluene and 0.298 parts by mass of tripentyl peroxyisononanoate was added dropwise as a dropwise initiator over a period of 180 minutes. Furthermore, simultaneously with the addition of the initiator, a solution containing 6.6 parts by mass of RHMA, 45.9 parts by mass of MMA, and 4.05 parts by mass of St was added dropwise over 180 minutes, while solution polymerization was carried out at 105°C–110°C, followed by curing over 100 minutes. A solution containing 1.20 parts by mass of toluene and 0.0750 parts by mass of stearyl phosphate was added to the obtained polymerization solution as a catalyst for the cyclization condensation reaction (cyclization catalyst), and the reaction was carried out under reflux at approximately 90°C–110°C for 1.5 hours to form a lactone ring structure. Subsequently, the obtained polymerization solution undergoes a cyclization condensation reaction in a multi-tube heat exchanger maintained at 220°C. Then, it is introduced at a processing rate of 90 parts by mass per hour (based on resin content) into a vented-type twin-screw extruder (L / D = 52) equipped with a vane-disc polymer filter (filtration accuracy 5 μm) at the front end for de-volatileization. The vented-type twin-screw extruder used has one vent port after discharge and four vent ports before discharge (referred to as vent ports 1, 2, 3, and 4 from the upstream side). The barrel temperature is set at 220°C, and the pressure is set at 13.3–400 hPa (10–300 mmHg). During de-volatileization, ion-exchanged water is added at a rate of 1.3 parts by mass per hour from behind vent ports 1, 2, and 3. The obtained methacrylic resin C has a weight average molecular weight of 102,000, a Mw / Mn ratio of 2.3, a glass transition temperature of 125°C, and the ratios of MMA units, styrene units, lactone ring structures, and RHMA units in the copolymer are 76.8% by mass, 4.6% by mass, 16.9% by mass, and 1.7% by mass, respectively.

[0121] (Manufacturing Example 4: Methacrylic Acid Resin D) A monomer composition comprising 63.08 parts by weight of MMA, 38.54 parts by weight of styrene, and 0.46 parts by weight of tripentyl 2-ethylhexanoate as a polymerization initiator was continuously fed at a rate of 1 kg / h into a 10 L completely mixed tank with a spiral wing. Continuous polymerization was carried out at an average residence time of 2.5 hours and a polymerization temperature of 150°C. The polymer was continuously drawn from the bottom of the polymerization tank at a constant liquid level and fed to a concentration device including a tubular heat exchanger and a vaporization tank for de-evaporation. The vacuum degree of the vaporization tank was set to 10–15 Torr. The resin flowing down from the vaporization tank was extracted by a screw pump, extruded from a wire die, water-cooled, granulated, and introduced into a desolventizing device to obtain granular methyl methacrylate-styrene copolymer. The copolymer was dissolved in methyl isobutyrate to prepare a 10% by weight methyl isobutyrate solution. In a 1000 mL autoclave, 500 parts by weight of a 10% methyl isobutyrate solution of the copolymer and 10% by weight of Pd / Cl as a hydrogenation catalyst were added. The mixture was kept at a hydrogen pressure of 9 MPa and 200°C for 15 hours to hydrogenate the aromatic double bonds in the styrene portion of the copolymer. After removing the hydrogenation catalyst by a filter, 0.04 parts by weight of RIKEMAL H-100 was added to the polymer solution, which was then fed into a concentration unit containing a tubular heat exchanger and a vaporization tank for de-evaporation. The vacuum degree of the vaporization tank was set to 10–15 Torr. The resin flowing down from the vaporization tank was extracted by a gear pump, extruded from a wire die, water-cooled, and granulated to obtain methacrylic resin D. The composition of the obtained particles was confirmed, and the absorbance measurement at a wavelength of 260 nm showed that the hydrogenation rate of the aromatic double bonds in the styrene portion was 99%. Furthermore, NMR measurements showed that the structural units of MMA and vinylcyclohexane monomers in the copolymer accounted for 60.7% and 39.3% by mass, respectively. The weight-average molecular weight was 167,000, the Mw / Mn ratio was 1.9, and the glass transition temperature was 118°C.

[0122] (Manufacturing Example 5: Methacrylic Acid Resin E) The composition was set as follows: 75.09 parts by mass of MMA and 26.04 parts by mass of styrene. All other aspects were handled in the same manner as in Manufacturing Example 4 to obtain methacrylic acid resin E. The composition of the obtained particles was confirmed. Absorbance measurements at 260 nm showed that the hydrogenation rate of the aromatic double bonds in the styrene portion was 99%. Furthermore, NMR measurements showed that the structural units of the MMA and vinylcyclohexane monomers from the copolymer were 73.2% and 26.8% by mass, respectively. The weight-average molecular weight was 148,000, the Mw / Mn ratio was 2.0, and the glass transition temperature was 118°C.

[0123] <Evaluation> The resins produced in the manufacturing examples were evaluated as follows. (1) Analysis of structural units In each manufacturing example, unless otherwise stated, the structural units of the manufactured thermoplastic resins were identified by 1H-NMR and 13C-NMR measurements, and their abundance was calculated. The measurement conditions for 1H-NMR and 13C-NMR measurements are as follows. ・Measuring equipment: ECZ400 manufactured by NEC Corporation ・Measuring solvent: CDCl3 or DMSO-d6 ・Measuring temperature: 40℃

[0124] (2) Determination of Molecular Weight The weight-average molecular weight (Mw) and number-average molecular weight (Mn) of the thermoplastic resin manufactured in the manufacturing example were determined using the following apparatus and conditions. ・Apparatus: Gel permeation chromatography (HLC-8320GPC) manufactured by Tosoh Co., Ltd. ・Determination conditions: Column: One TSKguardcolumn SuperH-H, two TSKgel SuperHM-M, and one TSKgel SuperH2500 were connected in series. Column temperature: 40℃ Developing solvent: Tetrahydrofuran, flow rate: 0.6 mL / min, 2,6-di-tert-butyl-4-methylphenol (BHT) was added at 0.1 g / L as an internal standard. Detector: RI (differential refractive index) detector, detection sensitivity: 3.0 mV / min Sample: 20 mL of tetrahydrofuran solution of 0.02 g of thermoplastic resin. Injection volume: 10 μL. Standard samples for calibration curve: Ten polymethyl methacrylates (PMMA) with known monodisperse peak molecular weights and different molecular weights were used (Polymer Laboratories; PMMA Calibration Kit MM-10). Peak molecular weight (Mp): Standard sample 1 1,916,000; Standard sample 2 625,500; Standard sample 3 298,900; Standard sample 4 138,600; Standard sample 5 60,150; Standard sample 6 27,600; Standard sample 7 10,290; Standard sample 8 5,000; Standard sample 9 2,810; Standard sample 10 850. Under the above conditions, the RI detection intensity relative to the dissolution time of the thermoplastic resin was determined. Based on the calibration curve obtained by measuring the standard samples for calibration curve, the weight-average molecular weight (Mw) and number-average molecular weight (Mn) of the thermoplastic resin were calculated.

[0125] (3) The glass transition temperature was determined according to JIS-K7121. The glass transition temperature (Tg) (°C) of the thermoplastic resin was determined. First, four pieces (4 parts) were cut from the sample that had been conditioned (placed at 23°C for 1 week) under standard conditions (23°C, 50%RH) as test pieces. Subsequently, a differential scanning calorimeter (PerkinElmer Diamond DSC) was used at a nitrogen flow rate of 25 mL / min. The sample was heated from room temperature (23°C) to 200°C at a rate of 10°C / min (one heating cycle), held at 200°C for 5 minutes to allow complete melting, and then cooled from 200°C to 40°C at a rate of 10°C / min, held at 40°C for 5 minutes. The glass transition temperature (Tg) (°C) was then measured at the intersection of the stepped change curve during the two heating cycles and the straight lines equidistant from the extended baselines on the vertical axis. Four measurements were taken for each sample, and the arithmetic mean of the four measurements (rounded to the nearest decimal) was used as the final value.

[0126] [Example 1] (Lens Forming) Using the methacrylic resin A obtained in Manufacturing Example 1, a biconvex lens with an optical axis thickness of 7.0 mm and an effective diameter of ϕ41 mm was formed using an injection molding machine (manufactured by FANUC Corporation, S-2000i50B). As a finishing process, one side of the surface containing the optical axis was an aspherical shape with a radius of curvature of R93.5 mm, a conic constant k = -1.12452, and an even-order constant was not set. The other side of the surface containing the optical axis was a spherical shape with a radius of curvature of R67 mm. The cylinder temperature was set to Tg +135°C of the methacrylic resin A used, and the mold temperature was set to Tg -15°C of the methacrylic resin A used. The pressure was held at 60 MPa for 4 seconds in the first stage, and then at 40 MPa for 3 seconds in the second stage to alleviate internal stress and strain in the molded part. Furthermore, the injection speed was set to 10 mm / s to perform the forming process, resulting in a lens-shaped product.

[0127] (Deposition of the moisture-proof layer) On the entire surface of the lens, an atomic layer deposition (ALD) apparatus (manufactured by Meiden Nanoprocess Innovations, PO-ALD) was used to deposit an alternating layer of aluminum-based and silicon-based constituent layers. First, using DMAI gas as the organometallic raw material, and using high-concentration ozone gas generated by a pure ozone generator (manufactured by Meidensha, MPOG-HM1A1) as the oxidant, a 10 nm thick aluminum-based constituent layer was formed by thermal ALD at a deposition temperature of 110°C. Next, using Orthrus (registered trademark, Air Liquide) as the organometallic raw material, and using high-concentration ozone gas generated by a pure ozone generator (manufactured by Meidensha, MPOG-HM1A1) as the reactant, a 10 nm thick silicon-based constituent layer was formed by thermal ALD at a deposition temperature of 110°C. The same film deposition process was repeated four times under identical conditions, with the thickness of the silicon-based component layer increasing to 30 nm in the fourth deposition. Based on this, a lens was obtained in which the entire surface was coated with alternating layers of aluminum-based and silicon-based components, totaling eight layers with a thickness of 100 nm. Here, the total thickness of the aluminum-based components is 40 nm, and the total thickness of the silicon-based components is 60 nm.

[0128] (Film Formation of Optical Functional Layer) An anti-reflective film comprising alternating layers of titanium oxide and silicon oxide is formed on the R67 mm spherical side of the lens by vacuum evaporation, thereby obtaining the lens.

[0129] [Example 2] During the formation of the moisture-proof layer, a thermal ALD at a formation temperature of 110°C was used to alternately repeat the formation of an aluminum-based composition layer with a thickness of 10 nm and a silicon-based composition layer with a thickness of 10 nm four times under the same conditions, resulting in a lens with a total thickness of 80 nm and an alternating laminated film having the composition shown in Table 1, covering the entire surface. Here, the total thickness of the aluminum-based composition layer is 40 nm, and the total thickness of the silicon-based composition layer is 40 nm. Except as described above, the process was the same as in Example 1 to obtain the lens.

[0130] [Example 3] During the formation of the moisture-proof layer, a thermal ALD at a formation temperature of 100°C was used to alternately repeat the formation of an aluminum-based composition layer with a thickness of 10 nm and a silicon-based composition layer with a thickness of 5 nm four times under the same conditions, resulting in a lens with a total thickness of 60 nm and an alternating laminated film having the composition shown in Table 1, covering the entire surface of the lens. Here, the total thickness of the aluminum-based composition layer is 40 nm, and the total thickness of the silicon-based composition layer is 20 nm. Except as described above, the process was the same as in Example 1 to obtain the lens.

[0131] [Example 4] During the formation of the moisture-proof layer, thermal ALD at a formation temperature of 100°C was used to alternately form an aluminum-based layer with a thickness of 5 nm and a silicon-based layer with a thickness of 5 nm eight times under the same conditions. The number of cycles was increased so that the thickness of the silicon-based layer in the eighth cycle was 25 nm. A total of 16 alternating laminated films with a thickness of 100 nm and the composition shown in Table 1 were formed. Here, the total thickness of the aluminum-based layer was 40 nm and the total thickness of the silicon-based layer was 60 nm. Except as described above, the process was the same as in Example 1 to obtain a lens.

[0132] [Example 5] During the formation of the moisture-proof layer, a thermal ALD at a formation temperature of 120°C was used to alternately repeat the formation of an aluminum-based composition layer with a thickness of 10 nm and a silicon-based composition layer with a thickness of 5 nm four times under the same conditions, resulting in a lens with a total thickness of 60 nm and an alternating laminated film with the composition shown in Table 1 covering the entire surface. Here, the total thickness of the aluminum-based composition layer is 40 nm, and the total thickness of the silicon-based composition layer is 20 nm. Furthermore, during the fabrication of the lens, a partial reflective film (reflectivity 50% ± 5%, wavelength range 450–650 nm) comprising alternating laminated films of titanium oxide and silicon oxide was formed on the R67 mm spherical side of the lens by vacuum evaporation. Except as described above, the process was the same as in Example 1, and the lens was obtained.

[0133] [Example 6] When manufacturing the lens, the methacrylic resin B obtained in Manufacturing Example 2 was used, and the process was carried out in the same manner as in Example 1, otherwise the lens was obtained.

[0134] [Example 7] When manufacturing the lens, the methacrylic resin C obtained in Manufacturing Example 3 was used, and the process was carried out in the same manner as in Example 1, otherwise the lens was obtained.

[0135] [Example 8] When manufacturing the lens, the methacrylic resin D obtained in Manufacturing Example 4 was used, and the process was carried out in the same manner as in Example 1, otherwise the lens was obtained.

[0136] [Example 9] When manufacturing the lens, the methacrylic resin E obtained in Manufacturing Example 5 was used, and the process was carried out in the same manner as in Example 1, otherwise the lens was obtained.

[0137] [Comparative Example 1] In Example 1, the moisture-proof layer was not formed, but otherwise the same procedure as in Example 1 was performed to obtain a lens.

[0138] [Comparative Example 2] In Example 5, the moisture-proof layer was not formed, but otherwise the same procedure as in Example 5 was performed to obtain a lens.

[0139] [Comparative Example 3] In Example 1, the moisture-proof layer was formed by vacuum evaporation, alternatingly forming an aluminum-based layer with a thickness of 10 nm and a silicon-based layer with a thickness of 10 nm four times under the same conditions, with the film formation time extended so that the thickness of the silicon-based layer in the fourth time was 30 nm. The moisture-proof layer was formed on the aspherical side of the lens (R93.5 mm) and then on the spherical side (R67 mm). Based on the above, a lens with alternating laminated films having a total thickness of 60 nm and having the composition shown in Table 1, covering both sides of the lens, was obtained. Otherwise, the process was the same as in Example 1, and the lens was obtained.

[0140] [Comparative Example 4] In Example 3, when forming the moisture-proof layer, an aluminum-based composition layer with a single film thickness of 60 nm was formed. Otherwise, the process was the same as in Example 3, and a lens was obtained.

[0141] <Evaluation> The optical molded articles produced in each embodiment and comparative example were evaluated as follows. The evaluation results are shown in Table 1.

[0142] (1) Composition of the moisture-proof film: The composition of the moisture-proof layer was confirmed by XPS measurement of the optical molded articles prepared in the Examples and Comparative Examples from the air interface side of the moisture-proof layer under the following conditions. The parts with the highest concentration of aluminum or silicon were used in the determination of the composition. <Analysis conditions> Equipment used: ULVAC-PHI VersaProbeII Excitation source: Monochromatic Al Kα Analysis size: Approximately 200 μm ϕ Photoelectron grazing angle: 45° Pass energy: 46.95 eV (Narrow) <Ar+ sputtering conditions> Acceleration: 1 kV Grating size: 2 mm × 2 mm with Zalar rotation

[0143] (2) Film thickness and structure of the moisture-proof film: The optical molded bodies produced in the Examples and Comparative Examples were cross-sectionally observed under the following conditions to confirm the uniformity of the film thickness of the moisture-proof layer. In addition, the crystallinity of each layer of the moisture-proof layer was evaluated based on the electron diffraction pattern. Assuming that there is no diffraction ring, it is an amorphous structure, it was confirmed whether each layer constituting the moisture-proof film is an amorphous structure. Equipment used (cross-section processing): Hitachi High-Tech NX5000, Japan FEI Helios650 Equipment used (cross-section observation, electron diffraction): Hitachi High-Tech HD2300 The evaluation of film thickness uniformity was performed according to the following criteria. A (Good): The difference between the film thickness of the thickest part and the film thickness of the thinnest part is within 10% of the film thickness of the thickest part. Wherein, if there are pinholes in the moisture-proof film, the part is excluded from the calculation. In addition, if there are pores in the moisture-proof film, the pores are included and considered as film thickness. B (Poor): The value obtained using the above calculation method exceeds 10%.

[0144] (3) Reliability test under high temperature and humidity conditions The optical molded bodies manufactured in the examples and comparative examples were subjected to reliability tests under the following temperature and humidity conditions to evaluate their reliability under high temperature and humidity conditions. Optical components were placed in a constant temperature and humidity chamber (ESPEC PL-2J) set to the specified temperature and humidity conditions and kept there for 168 hours, 336 hours and 504 hours before being removed and evaluated in (4) to (6). Temperature and humidity condition 1: 65℃, 90%RH Temperature and humidity condition 2: 85℃, 85%RH

[0145] (4) Shape stability evaluation: Before the reliability test under high temperature and high humidity environment (i.e., 0 hours) and after the specified time, the shape accuracy of the optical molded body is measured under non-contact conditions to evaluate the shape stability. Furthermore, the shape accuracy measurement is performed on the aspherical side without the film-coated optical functional layer because the spherical side with the anti-reflective film cannot obtain sufficient reflected light intensity, making it difficult to measure using this method. Equipment used: Mitsubishi Opto-Mechanical Manufacturing NH-3SPs Measurement surface: Aspherical side Measurement location: Through the optical center of the optical element, in the direction perpendicular to the flow Evaluation is performed according to the following criteria. A (Good): The absolute value of ΔPV is less than 2.0 μm. B (Good): The absolute value of ΔPV is greater than 2.0 μm but less than 5.0 μm. C (Poor): The absolute value of ΔPV is greater than 5.0 μm but less than 10.0 μm. D (Poor): The absolute value of ΔPV is greater than 10.0 μm. Here, ΔPV is the change in PV before and after the reliability test, and the Best Fit R value for 0 hours of common ground use is calculated.

[0146] (5) Visual evaluation: Visually observe the appearance of the optical molded body before (i.e., 0 hours) and after the specified time of the reliability test under high temperature and high humidity conditions to confirm the presence of cracks. The evaluation is based on the following criteria: A (Good): No cracks were found. B (Good): Slight cracks (about 1 to 2) were found. C (Poor): Many cracks (about several to dozens) were found. D (Poor): Numerous cracks were found.

[0147] (6) Optical Characteristic Evaluation Before the reliability test under high temperature and high humidity conditions (i.e., 0 hours) and after the specified time, the microscopic spectrophotometric reflectance of the optical functional layer of the optical molded body is measured. The change in the average reflectance value in the wavelength range of 450–650 nm before and after the reliability test is confirmed. When the optical functional layer is an antireflective film, the evaluation is conducted according to the following criteria: A (Good): Change less than 0.1% B (Good): Change greater than 0.1% but less than 0.2% C (Poor): Change greater than 0.2% but less than 0.5% D (Poor): Change greater than 0.5% When the optical functional layer is a partial reflective film, the evaluation is conducted according to the following criteria. A (Good): Change less than 2.0% B (Fairly Good): Change greater than 2.0% but less than 2.5% C (Fairly Poor): Change greater than 2.5% but less than 3.0% D (Poor): Change greater than 3.0%

[0148] [Table 1] Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Example 8 Example 9 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Shape of the molded body lens lens lens lens lens lens lens lens lens lens lens lens lens resin A A A A A B C D E A A A A Composition of the moisture-proof layer composition Aluminum-based composition layer aluminum atom% 27.7 26.9 29.4 29.8 25.0 27.6 27.8 27.5 27.4 - - 30.7 30.3 oxygen atom% 66.2 66.2 64.8 64.7 65.0 66.5 65.9 66.2 66.1 - - 69.3 65.9 carbon atom% 2.6 2.3 3.3 3.8 6.3 2.6 2.7 2.6 2.9 - - 0.0 3.3 The total of the above atom% 96.5 95.4 97.5 98.3 96.3 96.7 96.4 96.3 96.4 - - 100.0 99.5 Silicon-based constituent layers Silicon atom% 25.7 22.3 18.2 17.2 16.1 25.7 25.6 25.6 24.9 - - 27.8 - oxygen atom% 67.2 66.0 65.8 64.4 67.1 66.5 67.8 67.1 66.6 - - 72.2 - nitrogen atom% 1.5 2.3 1.2 1.3 0.3 1.8 1.3 1.6 1.6 - - 0.0 - The total of the above atom% 94.4 90.6 85.2 82.9 83.5 94.0 94.7 94.3 93.1 - - 100.0 - The ratio of the total thickness of aluminum-based layers to the total thickness of silicon-based layers (aluminum-based layers: silicon-based layers). 2:3 1:1 2:1 2:3 2:3 2:3 2:3 2:3 2:3 - - 2:3 - Number of moisture-proof layers 8 floors 8 floors 8 floors 16th floor 8 floors 8 floors 8 floors 8 floors 8 floors - - 8 floors 1st floor Moisture-proof layer film thickness uniformity A A A A A A A A A - - B A Construction of the moisture-proof layer Amorphous Amorphous Amorphous Amorphous Amorphous Amorphous Amorphous Amorphous Amorphous - - Amorphous Amorphous Types of optical functional layers Anti-reflective film Anti-reflective film Anti-reflective film Anti-reflective film Partial reflective film Anti-reflective film Anti-reflective film Anti-reflective film Anti-reflective film Anti-reflective film Partial reflective film Anti-reflective film Anti-reflective film Reliability testing 65℃, 90%RH Shape stability ΔPV after 168 hours μm -0.7 -0.8 1.3 -1.0 2.1 0.2 0.5 2.1 1.3 2.5 4.0 5.1 3.7 ΔPV after 336 hours μm -0.8 -0.7 2.2 -0.2 2.6 2.2 -0.6 2.6 1.1 4.1 3.3 4.9 5.2 ΔPV after 504 hours μm -1.0 -1.0 3.0 -0.6 4.6 3.1 -0.8 0.4 0.9 5.5 5.3 4.6 6.3 determination A A B A B B A B A C C C C Appearance evaluation (after 504 hours) A A A A A A A A A A A A D Optical property evaluation (after 504 hours) Change in average reflectivity % 0.07 0.12 0.08 0.00 2.03 0.11 0.05 0.02 0.03 0.19 3.39 0.13 - determination A B A A B B A A A B D B - 85℃, 85%RH Shape stability ΔPV after 504 hours μm 3.5 4.1 3.6 1.7 2.9 3.7 2.9 0.5 -0.5 5.1 6.8 8.3 11.4 determination B B B A B B B A A C C D D Appearance evaluation (after 504 hours) B B B A B B B A A D D D D Optical property evaluation (after 504 hours) Change in average reflectivity % 0.00 0.03 0.05 0.00 1.91 0.11 0.03 0.02 0.02 0.16 3.76 0.15 - determination A A A A A B A A A B D B - [Industrial Applicability]

[0149] The optical molded body of this embodiment has sufficient moisture-proof performance and has high shape stability and optical performance stability even in high temperature and high humidity environments.

[0150] Examples of optical molded bodies suitable for use in this embodiment include optical components used in household goods, office automation equipment, audio-visual equipment, batteries and electrical parts, lighting equipment, etc. Examples include: light guide plates, display front panels, and touch panels for displays of smartphones, PDAs, tablet PCs, LCD TVs, etc.; lenses for smartphone and tablet PC cameras, or lenses or prisms for telescopes (periscope cameras) in folding optical systems; and near-infrared sensors (LiDAR; Light Detection) for VR (virtual reality) / AR (augmented reality) / MR (mixed reality) / XR (cross-realization) head-mounted displays or LCD projectors. Optical components such as those from Ranging (Guangda), including prism elements, waveguides, freeform light guides, lenses, especially small, thin-walled optical lenses with uneven thickness; optical fibers, optical fiber coating materials, lenses or prisms for optical communication, lenses, Fresnel lenses, phase plates with microlens arrays, optical cover components, substrates constituting polarization separation elements, polarizing elements or retardation films, substrates or lenses bonded to them, etc.

[0151] As optical components in automobiles and other applications, examples include: light guide plates for vehicle displays; optical covers for front panels or including curved shapes used in vehicle dashboards, instrument clusters, car navigation systems, information displays, rear-seat displays, etc.; lenses or prisms, light direction conversion elements, waveguides, light guides, combiners, dustproof sheets, optical cover parts, etc. used in head-up displays; camera lenses (especially front lenses) for vehicles; light guide rods, etc.

[0152] As optical components used in aerial displays, examples include: substrates for regressive reflectors or partial transmissive mirrors; optical components with sub-millimeter shapes used to form dihedral reflector arrays; microlens arrays; passive light components; substrates for concave and convex mirrors; lenses used to magnify or reduce images; light guide components; and direction conversion elements.

[0153] In addition to the above, it can also be preferably used as a display device component for digital signage that transmits information on a thin display connected to the network for publicity, advertising, or other purposes in places such as camera focus plates, outdoor spaces, shops, public institutions, and transportation facilities.

Claims

1. An optical molded body, characterized in that: the optical molded body sequentially comprises a resin substrate, a moisture-proof layer, and an optical functional layer, wherein the moisture-proof layer is an amorphous film containing aluminum, silicon, oxygen, carbon, and nitrogen, and the optical functional layer is an anti-reflective film and / or a partially reflective film.

2. The optical molded body of claim 1, wherein the moisture-proof layer comprises an aluminum-based composition layer containing aluminum, oxygen, and carbon.

3. The optical molded body of claim 2, wherein in the moisture-proof layer, the aluminum-based composition layer comprises a layer with a carbon content of 0.1 to 10 atomic percent.

4. The optical molded article of claim 2, wherein in the moisture-proof layer, the total content of aluminum, oxygen and carbon in the aluminum-based constituent layer is 70 atomic% or more.

5. The optical molded body as claimed in claim 1 or 2, wherein the moisture-proof layer comprises a silicon-based composition layer containing silicon, oxygen, and nitrogen.

6. The optical molded article of claim 5, wherein in the moisture-proof layer, the silicon-based composition layer comprises a layer with a nitrogen content of 0.1 to 10 atomic percent.

7. The optical molded article of claim 5, wherein in the moisture-proof layer, the total content of silicon, oxygen and nitrogen in the silicon-based composition layer is 70 atomic% or more.

8. The optical molded article of claim 5, wherein the moisture-proof layer comprises an alternating laminated structure of the aluminum-based constituent layer and the silicon-based constituent layer.

9. The optical molded body of claim 8, wherein in the moisture-proof layer, the ratio of the total thickness of the aluminum-based constituent layers to the total thickness of the silicon-based constituent layers (aluminum-based constituent layers: silicon-based constituent layers) is 1:4 to 4:

1.

10. The optical molded body of claim 9, wherein in the above-mentioned alternating layered structure, the total number of layers is 6 or more.

11. The optical molded article of claim 10, wherein the moisture-proof layer covers the entire surface of the molded article, and the film thickness distribution is within 10%.

12. The optical molded article of claim 10, wherein the resin substrate is formed from any one or more resins selected from the group consisting of methacrylic resins, polyester resins, carbonate resins, norcamphene resins, and modified norcamphene resins.