Resin optical element and method for manufacturing resin optical element

Abstract

The purpose of the present invention is to provide a resin optical element that, at all of a plurality of optically effective surfaces, exhibits excellent adhesion between an optical thin film or inorganic oxide film formed on an optically effective surface and the resin surface layer of a substrate, and maintains good film adhesion and crack resistance even after high-temperature, high-humidity testing.　In order to solve the abovementioned problem, the present invention provides a resin optical element having at least two optically effective surfaces, each comprising a laminated structure including a resin substrate and an optical thin film, said resin optical element being characterized in that the laminated structure is obtained by sequentially forming the resin substrate, an inorganic oxide film, and the optical thin film, and the surface layer degradation index (Isurf / Iint) of the optically effective surface on a tape-side release surface of the resin substrate as measured by X-ray photoelectron spectroscopy satisfies the following relationship: 0.8≦Isurf / Iint≦1 (where Isurf is the normalized intensity of the C=O bond-derived peak in the surface layer of the resin substrate, and Iint is the normalized intensity of the C=O bond-derived peak of the resin substrate.) is satisfied.

Description

Resin optical element and method for manufacturing a resin optical element

[0001] The present invention relates to a resin optical element and a method for manufacturing a resin optical element.

[0002] Traditionally, glass was used for optical elements such as lenses and prisms, but in recent years, resin materials have come into use due to their ability to be lighter, smaller, and offer greater design flexibility, such as the ability to create aspherical lenses. Commonly known resin materials used in optical components include methacrylic resins, styrene resins, polycarbonate resins, and cyclic olefin resins.

[0003] Furthermore, in recent years, with the dramatic improvement in the performance of optical products such as VR (virtual reality) and AR (augmented reality), the complexity and precision of optical design in optical products have increased even further. As a result, optical elements used in optical products require not only high shape but also stringent characteristics, including high durability, in the optical thin films deposited on the surface of the optical elements.

[0004] Optical thin films are usually deposited using physical vapor deposition (PVD). However, when deposited on resin materials, backscattered electrons generated during PVD repeatedly collide and reflect off the inner walls of the apparatus before hitting the substrate. This causes deterioration and alteration of the substrate surface, resulting in reduced durability.

[0005] For example, Patent Document 1 discloses a deposition technique that uses only resistance heating deposition. Also, Patent Document 2 discloses a technique for suppressing the generation of backscattered electrons by backscattered electron trapping.

[0006] Japanese Patent Publication No. 58-60701 Japanese Patent Publication No. 2010-106289

[0007] However, with the technology described in Patent Document 1, the deposition materials that can be deposited by resistance heating deposition are limited to those with relatively low melting points, making it difficult to deposit optical thin films that satisfy the stringent characteristics required for VR and AR. Furthermore, even when using a backscattered electron trap as in Patent Document 2, it is not possible to completely eliminate the generation of backscattered electrons, and deterioration of the substrate was unavoidable, especially when depositing optical thin films with large thicknesses or when depositing films on multiple surfaces.

[0008] Therefore, resin-based optical elements obtained by conventional methods, such as those described in Patent Documents 1 and 2, are insufficient in terms of the high optical performance required for optical products such as VR and AR in recent years, as well as the adhesion between the resin substrate constituting the optical element and the optical thin film, and resistance to high temperature and high humidity tests. Further improvements were desired.

[0009] The present invention has been made in view of the above-mentioned problems, and one aspect of the present invention aims to provide a resin optical element and a method for manufacturing the same, which have excellent adhesion between an optical thin film formed on the surface and a resin substrate in a plurality of laminated structures, and good shape retention before and after film formation. Another aspect of the present invention aims to provide a resin optical element which has excellent adhesion between an optical thin film and / or inorganic oxide film formed on the surface and the surface layer of the resin part of the substrate even after high temperature and high humidity testing. Furthermore, another aspect of the present invention aims to provide a resin optical element in which the optical thin film and / or inorganic oxide film formed on the surface maintains crack resistance even after high temperature and high humidity testing. Yet another aspect of the present invention aims to provide a method for suppressing deterioration of the surface layer of a resin substrate due to collisions of backscattered electrons with the surface layer of a resin optical element having a plurality of optically effective surfaces. Note that the description of these problems does not preclude the existence of other problems. Note that one aspect of the present invention does not need to solve all of these problems. Note that it is possible to extract other problems from the description in the specification, drawings and claims.

[0010] The present inventors have diligently researched resin optical elements having at least two optically effective surfaces, comprising a laminated structure of a resin substrate and an optical thin film, in order to solve the above problems. As a result, they have found that by sequentially forming the resin substrate, an inorganic oxide film with a thickness of 300 to 500 nm, and the optical thin film in the laminated structure, and optimizing the surface degradation index of the resin substrate on the optically effective surface as determined by X-ray photoelectron spectroscopy, it is possible to improve the adhesion between the optical thin film and / or inorganic oxide film and the surface layer of the resin part of the substrate, as well as the surface smoothness, while maintaining high optical performance.

[0011] That is, the present invention is as follows. (1) A resin optical element having at least two optically effective surfaces composed of a laminated structure including a resin base material and an optical thin film, wherein the laminated structure is formed by sequentially forming the resin base material, an inorganic oxide film and the optical thin film, and the surface layer degradation index (I ｓｕｒｆ / I ｉｎｔ ) on the tape-side peeled surface of the resin base material obtained by X-ray photoelectron spectroscopy analysis on the optically effective surface satisfies the following relationship: 0.8≦I ｓｕｒｆ / I ｉｎｔ ≦1 (where I ｓｕｒｆ represents the normalized intensity of the peak derived from the C=O bond in the surface layer of the resin base material, and I ｉｎｔ represents the normalized intensity of the peak derived from the C=O bond in the resin base material). A resin optical element characterized by satisfying the above. (2) A resin optical element having at least two optically effective surfaces composed of a laminated structure including a resin base material and an optical thin film, wherein the laminated structure is formed by sequentially forming the resin base material, an inorganic oxide film and the optical thin film, and the base material degradation index (I ｓｕｒｆ / I ｉｎｔ ) on the base-side peeled surface of the resin base material obtained by X-ray photoelectron spectroscopy analysis on the optically effective surface satisfies the following relationship: 0.80≦I ｓｕｒｆ / I ｉｎｔ ≦1.00. A resin optical element characterized by satisfying the above. (3) The surface layer degradation index (I ｓｕｒｆ / I ｉｎｔ ) on the tape-side peeled surface of the resin base material obtained by X-ray photoelectron spectroscopy analysis on the optically effective surface satisfies the following relationship: 0.70≦I ｓｕｒｆ / I ｉｎｔ ≦1.00 (where I ｓｕｒｆ represents the normalized intensity of the peak derived from the C=O bond in the surface layer of the resin base material, and I ｉｎｔ(2) A resin optical element according to (2), characterized in that it satisfies the following conditions. (4) A resin optical element according to any one of (1) to (3), characterized in that the thickness of the inorganic oxide film is 300 to 500 nm. (5) A resin optical element according to any one of (1) to (4), characterized in that the resin substrate contains a radical decomposition type resin having quaternary carbon in its main chain. (6) A resin optical element according to any one of (1) to (5), characterized in that the inorganic oxide film contains one or more elements selected from the group consisting of silicon, aluminum, titanium, hafnium, zirconium, tantalum, cerium, and niobium. (7) A resin optical element according to any one of (1) to (6), characterized in that the optical thin film is an anti-reflective film. (8) The resin optical element according to any one of (1) to (7), wherein the optical thin film is a partial reflective film, and the partial reflective film is a multilayer film obtained by alternately laminating five to nine layers of a high refractive index film with a refractive index of 1.90 to 2.46 and a low refractive index film with a refractive index of 1.44 to 1.60, the thickness of the partial reflective film is smaller than the thickness of the inorganic oxide film, the spectral reflectance of the partial reflective film in the wavelength range of 450 to 650 nm is 30% to 60%, and the difference between the maximum and minimum values ​​of the spectral reflectance is 2% to 10%. (9) The resin optical element according to (8), wherein the refractive index of the layer in contact with the inorganic oxide film in the multilayer film is 1.90 to 2.20. (10) The resin optical element according to (9), wherein, when the layer in contact with the inorganic oxide film in the multilayer film is considered the first layer, the refractive index of the layers other than the first layer of the high refractive index film is greater than the refractive index of the first layer. (11) The resin optical element according to (8) or (9), characterized in that the refractive index of the low refractive index film among the multilayer films is smaller than the refractive index of the inorganic oxide film. (12) A method for manufacturing a resin optical element according to any one of (1) to (11), comprising: a first film formation step of forming an inorganic oxide film with a thickness of 300 nm or more on a resin substrate of all optically effective surfaces by a dry film formation method that does not generate backscattered electrons in principle; and a second film formation step of forming the optical thin film by a film formation method that can generate backscattered electrons in principle.(13) The method for manufacturing a resin optical element according to (12), characterized in that the dry film deposition method is a resistance heating deposition method and / or an electron beam bombarded indirect heating deposition method. (14) A method for suppressing surface layer deterioration of a resin optical element, characterized in that a first film deposition step is performed in which an inorganic oxide film of sufficient thickness to sufficiently shield backscattered electrons is deposited on all of the resin substrates by a dry film deposition method that does not generate backscattered electrons in principle, thereby suppressing deterioration of the surface layer of the surface due to collisions with backscattered electrons during a second film deposition step in which the optical thin film is deposited by a film deposition method that can generate backscattered electrons in principle.

[0012] According to one aspect of the present invention, it is possible to provide a resin optical element that has excellent adhesion between the optical thin film or inorganic oxide film formed on the surface of multiple optical effective surfaces and the resin surface layer of the substrate, and that maintains good film adhesion and crack resistance even after high temperature and high humidity testing. Furthermore, according to one aspect of the present invention, it is possible to provide a resin optical element that has excellent adhesion between the optical thin film and / or inorganic oxide film formed on the surface and the resin surface layer of the substrate on multiple optical effective surfaces. Moreover, it is possible to provide a resin optical element that maintains excellent adhesion between the optical thin film and / or inorganic oxide film formed on the surface and the resin surface layer of the substrate even after high temperature and high humidity testing, and in addition, it is possible to provide a resin optical element in which the optical thin film and / or inorganic oxide film formed on the surface maintains crack resistance even after high temperature and high humidity testing. Furthermore, according to one aspect of the present invention, it is possible to provide a method for suppressing surface layer degradation of a resin optical element having multiple optical effective surfaces, which can suppress the degradation of the surface layer due to collisions of backscattered electrons with the surface layer of the resin substrate. Note that the description of these effects does not preclude the existence of other effects. It should be noted that one embodiment of the present invention does not need to solve all of these effects. Other effects will naturally become clear from the description in the specification, drawings, and claims, and it is possible to extract other effects from the description in the specification, drawings, and claims.

[0013] Figure 1 is a schematic diagram showing a cross-section parallel to and including the optical axis Z of an example of a plastic lens (biconvex lens) formed in this embodiment. Figure 2 is a schematic diagram showing a cross-section parallel to and including the optical axis Z of an example of a plastic lens (plano-convex lens) formed in this embodiment. Figure 3 is a schematic diagram showing a cross-section parallel to the bottom surface of an example of a prism (right-angle prism) formed in this embodiment. Figure 4 is a schematic diagram showing the positional relationship between the gate provided on the bottom surface and the first, second, and third optically effective surfaces of an example of a prism (right-angle prism) formed in this embodiment. Figure 5(a) is a schematic configuration diagram (front view) of a typical deposition apparatus having a resistance heating type deposition source used for resistance heating deposition, and Figure 5(b) is a schematic configuration diagram (front view) of a typical deposition apparatus having an electron beam heating type deposition source used for electron beam heating deposition.

[0014] Hereinafter, embodiments for carrying out the present invention (hereinafter referred to as "this embodiment") will be described in detail with reference to drawings as necessary. However, the present invention is not limited to the following description and can be implemented in various modifications within the scope of its gist. Here, Figures 1 and 2 show examples of plastic lenses (resin optical elements) formed in this embodiment, respectively. Figure 3 shows a cross-section parallel to the bottom surface of an example of a prism (right-angle prism) formed in this embodiment, and Figure 4 shows the positional relationship between the gate provided on the bottom surface and the first, second, and third effective optical surfaces of an example of a prism (right-angle prism) formed in this embodiment.

[0015] <Resin Optical Element> The resin optical element of this embodiment has at least two optically effective surfaces, which are made up of a laminated structure comprising a resin substrate and an optical thin film. Here, "optically effective surface" refers to the minimum optical surface required to produce the optical properties required of the optical element, and is the path of the light ray. More specifically, it is the surface through which the principal ray is transmitted and / or reflected. For example, in the case of a lens, it refers to the curved surface described by the aspherical surface formula and the curved surface or plane opposite to said curved surface. In the case of a prism, it refers to the incident surface, the reflective surface, and the exit surface of light.

[0016] The resin optical elements shown in Figures 1 and 2 each have two optical effective surfaces: a first optical effective surface 11 and a second optical effective surface 21. The resin optical element shown in Figure 3 has three optical effective surfaces: a first optical effective surface 11, a second optical effective surface 21, and a third optical effective surface 31. Furthermore, the resin optical element shown in Figure 4 has a first optical effective surface, a second optical effective surface, and a third optical effective surface formed to surround a gate provided on the bottom surface.

[0017] The optically effective surface may have a microstructure on its surface. If the optically effective surface has a microstructure on its surface, the surface on which the microstructure is formed may be counted as one surface. Examples of microstructures include Fresnel lenses, prism sheets, lenticular lenses, microlens arrays, optical members with sub-millimeter shapes for forming two-sided corner reflector arrays, optical direction conversion elements, diffraction gratings, microfluidic structures, and the like.

[0018] (Resin Substrate) In this embodiment, the resin optical element uses a substrate (resin substrate) made of a molded resin on the optically effective surface. The shape of the resin substrate is not particularly limited and can be used in various forms such as film / sheet, flat plate, curved, bowl-shaped, lens-shaped, block-shaped, spherical, rod-shaped, columnar, cylindrical, tubular, and fibrous shapes. In addition to the above shapes, shapes with fine shaping applied to the surface can also be used. As a more specific example, the shape of the substrate in this embodiment may be a lens, prism, light guide, diffraction grating, cover, or optical fluid dynamics device. In the resin optical element shown in Figure 1, a resin substrate 15 (lens) with a curved shape is disclosed; in the resin optical element shown in Figure 2, a resin substrate 15 (lens) with a bowl-shaped shape is disclosed; and in the resin element shown in Figure 3, a triangular prism-shaped resin substrate 15 (prism) is disclosed.

[0019] The method for manufacturing the resin substrate is not particularly limited, and known methods can be used. Examples include injection molding, extrusion molding, casting, compression molding, injection compression molding, vacuum molding, pressure molding, blow molding, and casting polymerization. Furthermore, the molded article obtained by the above manufacturing method may be further ground, turned, or polished.

[0020] When extrusion molding is used as the method for manufacturing the resin substrate, for example, the polishing roll method or the air knife method may be used. In the polishing roll method, it is preferable to compress and cool the molten resin between a set of three polishing rolls. It is preferable to use a feeding mechanism for the polishing rolls that minimizes driving irregularities. Instead of the polishing rolls, a configuration may be used in which a pair of seamless metal belts for cooling the molten resin are arranged opposite each other at a predetermined distance at the outlet of the extruder.

[0021] When cast molding is used as the manufacturing method for the resin substrate, a glass casting method may be used. In the glass casting method, the raw material for the resin substrate is poured between glass plates with good flatness and smoothness, and then a polymerization process is carried out to solidify the raw material for the resin substrate. The cast molding is not limited to the glass casting method described above. For example, an endless belt made of metal facing each other may be used as the cast. In this case, the resin substrate can be continuously manufactured by carrying out the polymerization process while rotating the endless belt. Other casting methods include using a metal plate instead of glass in the glass casting method.

[0022] When using grinding, turning, or polishing as the manufacturing method for the resin substrate, diamond wheels, diamond turning, or diamond polishing may be used.

[0023] The above-mentioned resin substrate can be made of, for example, a thermoplastic resin, a thermosetting resin, or an active energy ray curable resin. Of these, it is preferable that it contains a thermoplastic resin, and it is particularly preferable that it consists of a thermoplastic resin.

[0024] Examples of thermoplastic resins used include methacrylic resins, polycarbonate resins, polyester resins, aramid resins, polyolefin resins, modified polyolefin resins, norbornene resins, modified norbornene resins, alicyclic olefin resins, polystyrene resins, cyclic block copolymers (CBCs), maleimide resins, polyvinyl chloride resins (PVC), triacetylcellulose (TAC), polyphenylene sulfide (PPS), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyethylene naphthalate (PEN), ABS resins, polyimide (PI), and polyetherimide (PEI). In particular, since excellent transparency is desirable for optical applications, methacrylic resins, polycarbonate resins, polyester resins, polyolefin resins, norbornene resins, modified norbornene resins, alicyclic olefin resins, polystyrene resins, maleimide resins, TAC, PET, PEN, and PEI are preferred. From the viewpoint of color tone, any one selected from the group consisting of methacrylic resins, polycarbonate resins, polyester resins, norbornene resins, alicyclic olefin resins, TAC, and PET is more preferred. From the viewpoint of moldability, any one selected from the group consisting of methacrylic resins, polycarbonate resins, polyester resins, norbornene resins, and alicyclic olefin resins is even more preferred. Furthermore, from the viewpoint of low birefringence and ease of surface degradation due to backscattered electron damage, and ease of obtaining the effects of the present invention, methacrylic resins are particularly preferred. The above thermoplastic resins may be used individually or in combination of two or more.

[0025] (Methacrylic resin) When a methacrylic resin is used as the thermoplastic resin, either a homopolymer of methyl methacrylate (MMA) or a copolymer of MMA and other monomers can be used. From the viewpoint of thermal stability, heat resistance, and low birefringence, it is preferable to use a copolymer, and more preferably to use a random copolymer. The composition of the methacrylic resin is not particularly limited, but it may contain 50 to 100 wt% of methacrylic acid ester monomer units (A), 0 to 30 wt% of structural units (B) having a ring structure in the main chain and / or side chains, and 0 to 20 wt% of other vinyl monomer units (C) copolymerizable with methacrylic acid ester monomers.

[0026] Examples of methacrylate monomer units (A) include, but are not limited to, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, t-butyl methacrylate, 2-ethylhexyl methacrylate, cyclopentyl methacrylate, cyclohexyl methacrylate, cyclooctyl methacrylate, tricyclodecyl methacrylate, isobornyl methacrylate, phenyl methacrylate, benzyl methacrylate, 1-phenylethyl methacrylate, 2-phenoxyethyl methacrylate, 3-phenylpropyl methacrylate, and 2,4,6-tribromophenyl methacrylate. From the viewpoint of heat resistance, optical properties, and weather resistance of the resulting methacrylic resin, the methacrylic ester monomers are preferably methyl methacrylate, ethyl methacrylate, cyclohexyl methacrylate, phenyl methacrylate, and benzyl methacrylate. From the viewpoint of availability, methyl methacrylate and benzyl methacrylate are preferred. The methacrylic ester monomers may be used individually or in combination of two or more.

[0027] The methacrylic acid ester monomer units (A) of the methacrylic resin can be appropriately adjusted in ratio to structural units (B) having a ring structure in the main chain and / or side chain (described later), and other vinyl monomer units (C) copolymerizable with the methacrylic acid ester monomer. This allows for sufficient thermal stability and heat resistance, good hue, low hygroscopicity, and reduction of birefringence caused by orientation and residual stress during molding in the resin optical elements of this embodiment. From these viewpoints, the content of methacrylic acid ester monomer units (A) is preferably 50 wt% or more, more preferably 55 wt% or more, and even more preferably 60 wt% per 100 wt% of the methacrylic resin. It is also preferably 100 wt% or less, more preferably 95 wt% or less, and even more preferably 90 wt% or less.

[0028] The structural unit (B) having a ring structure in the main chain and / or side chain is not limited to the following, but it is preferable to have at least one structural unit selected from the group consisting of maleimide structural units (B-1), glutaric acid anhydride structural units (B-2), glutarimide 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 of two or more types.

[0029] As the maleimide-based structural unit (B-1) constituting the methacrylic resin, the structural unit represented by the following general formula (1) is preferably used. In the above general formula (1), R １ This represents any of the group selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 14 carbon atoms, a cycloalkyl group having 3 to 14 carbon atoms, an alkoxy group having 1 to 14 carbon atoms, an arylalkyl group having 7 to 14 carbon atoms, and an aryl group having 6 to 14 carbon atoms, wherein the alkyl group, cycloalkyl group, alkoxy group, arylalkyl group, and aryl group may have substituents on carbon atoms.

[0030] The monomers for forming the maleimide-based structural unit (B-1) are not limited to the following, but include, for example, maleimides: N-methylmaleimide, N-ethylmaleimide, N-n-propylmaleimide, N-isopropylmaleimide, N-n-butylmaleimide, N-isobutylmaleimide, N-t-butylmaleimide, N-n-pentylmaleimide, N-n-hexylmaleimide, N-n-heptylmaleimide, N-n-octylmaleimide, N-laurimide. N-alkyl-substituted maleimides such as lumaleimide; N-cycloalkyl-substituted maleimides such as N-cyclopentylmaleimide, N-cyclohexylmaleimide, 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, and 1-cyclohexyl-3,4-diphenyl-1H-pyrrole-2,5-dione; N-phenylmaleimide, 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- Examples of N-aryl group-substituted maleimides include (4-benzylphenyl)maleimide, N-(2,4,6-tribromophenyl)maleimide, N-naphthylmaleimide, N-anthracenylmaleimide, 3-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 units (B-1) may be used individually or in combination of two or more.

[0031] The content of maleimide-based structural units (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, based on 100% by mass of the methacrylic resin. When the content of maleimide-based structural units (B-1) is within the above range, a resin with good moldability, heat resistance, optical properties, low birefringence, and low water absorption can be obtained, which is therefore preferable.

[0032] The methacrylic resin containing the maleimide structural unit (B-1) may further contain, if necessary, structural units derived from other monomers copolymerizable with the methacrylic acid ester monomer unit (A) and the maleimide structural unit (B-1), such as aromatic vinyl monomer units and unsaturated nitrile monomer units. The aromatic vinyl monomer is not particularly limited, but examples include styrene and α-methylstyrene, with styrene being preferred. The unsaturated nitrile monomer is not particularly limited, but examples include acrylonitrile, methacrylonitrile, and ethacrylonitrile, with acrylonitrile being preferred.

[0033] As the glutaric acid anhydride-based structural unit (B-2) constituting the methacrylic resin, the structural unit represented by the following general formula (2) is preferably used. In the above general formula (2), R １ and R ２ Each of these independently represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, which may be substituted with a hydroxyl group.

[0034] The method for forming the glutaric acid anhydride structural unit (B-2) described above is not particularly limited, but for example, one method is to copolymerize a monomer having the structure represented by the following general formula (3) with a monomer forming the methacrylate ester monomer unit (A) described above, and then cyclize it by heat treatment in the presence or absence of a catalyst. In the above general formula (3), R １ R represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, which may be substituted with a hydroxyl group. ２ represents a hydrogen atom or a t-butyl group.

[0035] Furthermore, within the limits within which the effects of the present invention can be achieved, monomers with the structure represented by general formula (3) may remain unreacted in the methacrylic resin.

[0036] The glutarimide-based structural unit (B-3) constituting the methacrylic resin may be formed after resin polymerization. The structural unit represented by the following general formula (4) is preferably used as the (B-3) structural unit. In the above general formula (4), R １ and R ２ Each of these independently represents a hydrogen atom or a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, and the alkyl group may be substituted with a hydroxyl group. Also, R ３ R represents any of the following selected from 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. Particularly preferred is R １ , R ２ , and R ３ These are all methyl groups.

[0037] The glutarimide-based structural units (B-3) described above may be used individually or in combination of two or more types.

[0038] The content of glutarimide-based structural units (B-3) is preferably 1 to 70% by mass, and more preferably 3 to 60% by mass, based on 100% by mass of the methacrylic resin. A glutarimide-based structural unit (B-3) content within the above range is preferable because it yields a resin with good moldability, heat resistance, optical properties, and low birefringence. The content of glutarimide-based structural units (B-3) can be calculated, for example, by the method described in

[0136] to

[0137] of International Publication No. 2015 / 098096.

[0039] The methacrylic resin containing glutarimide-based structural units (B-3) may further contain aromatic vinyl monomer units as needed. The aromatic vinyl monomer is not particularly limited, but examples include styrene and α-methylstyrene, with styrene being preferred.

[0040] The lactone ring structural unit (B-4) constituting the methacrylic resin may be formed after resin polymerization. The structural unit represented by the following general formula (5) is preferably used as the (B-4) structural unit. In the above general formula (5), R １ , R ２ , and R ３ Each of these independently represents either a hydrogen atom or an organic group having 1 to 20 carbon atoms. The organic group may also contain an oxygen atom. The lactone ring structural unit (B-4) described above may be used individually or in combination of two or more types.

[0041] Lactone ring structural units can be formed, for example, by copolymerizing an acrylic acid monomer having a hydroxyl group with a methacrylic acid ester monomer such as methyl methacrylate to introduce a hydroxyl group and an ester group or carboxyl group into the molecular chain, and then causing de-alcoholization (esterification) or dehydration condensation (hereinafter also referred to as "cyclization condensation reaction") between these hydroxyl groups and the ester group or carboxyl group.

[0042] Examples of acrylic acid monomers having a hydroxyl group used in polymerization include 2-(hydroxymethyl)acrylic acid, 2-(hydroxyethyl)acrylic acid, alkyl 2-(hydroxymethyl)acrylate, and alkyl 2-(hydroxyethyl)acrylate, with methyl 2-(hydroxymethyl)acrylate and ethyl 2-(hydroxymethyl)acrylate being preferred.

[0043] The content of lactone ring structural units (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, based on 100% by mass of the methacrylic resin. When the content of lactone ring structural units (B-4) is within the above range, a resin with good moldability, heat resistance, optical properties, low birefringence, solvent resistance, and surface hardness is obtained, which is therefore preferable.

[0044] The methacrylic resin containing the lactone ring structural unit (B-4) may further contain aromatic vinyl monomer units as needed. The aromatic vinyl monomer is not particularly limited, but examples include styrene and α-methylstyrene, with styrene being preferred.

[0045] The acid anhydride structural unit (B-5) constituting the methacrylic resin can be formed using, for example, an acid anhydride such as maleic anhydride, a half-ester of the acid anhydride with a linear or branched alcohol having 1 to 20 carbon atoms, or an α,β-ethylenically unsaturated carboxylic acid.

[0046] The content of acid anhydride structural units (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, based on 100% by mass of the methacrylic resin. A content of acid anhydride structural units (B-5) within the above range is preferable because it yields a resin with good moldability, heat resistance, optical properties, and low birefringence.

[0047] The methacrylic resin containing the acid anhydride structural unit (B-5) may further contain, if necessary, structural units derived from other monomers copolymerizable with the methacrylic acid ester monomer unit (A) and the acid anhydride structural unit (B-5), such as aromatic vinyl monomer units and unsaturated nitrile monomer units.

[0048] The aromatic vinyl monomer is not particularly limited, but examples include styrene and α-methylstyrene, with styrene being preferred. The unsaturated nitrile monomer is not particularly limited, but examples include acrylonitrile, methacrylonitrile, and ethacrylonitrile, with acrylonitrile being preferred.

[0049] The aromatic structural unit (B-6) constituting the methacrylic resin is preferably a structure represented by the following general formula (6). In the above general formula (6), R １ R represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and the alkyl group may be substituted with, for example, a hydroxyl group. ２R is selected from 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 allyloxy group having 6 to 8 carbon atoms. ２ These may all be the same group or different groups. Also, R ２ They may form a ring structure with each other. In general formula (6), n represents an integer from 0 to 5.

[0050] Specific examples of monomers represented by the above general formula (6) are not particularly limited, but 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-diphenylethylene, ilopropenylbenzene (α-methylstyrene), isopropenyltoluene, isopropenylethylbenzene, isopropenylpropylbenzene, isopropenylbutylbenzene, isopropenylpentylbenzene, isopropenylhexylbenzene, isopropenyloctylbenzene, etc. Among the above, styrene and α-methylstyrene are preferred, and styrene is more preferred from the viewpoint of providing fluidity and reducing unreacted monomers by improving the polymerization conversion rate.

[0051] The content of aromatic structural units (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, based on 100% by mass of the methacrylic resin. It is preferable that the content of aromatic structural units (B-6) be within the above range because it yields a resin with good moldability, heat resistance, optical properties, and low birefringence.

[0052] As the alicyclic structural unit (B-7) constituting the methacrylic resin, a saturated alicyclic hydrocarbon compound having a vinyl group is preferably used.

[0053] The number of carbon atoms constituting the alicyclic structure is typically in the range of 4 to 30, preferably 5 to 20, more preferably 5 to 15, and most preferably 6, from the viewpoint of mechanical strength, heat resistance, and moldability.

[0054] Specific examples of such monomers include vinylcyclohexane, isopropenylcyclohexane, 4-methylisopropenylcyclohexane, 3-methylisopropenylcyclohexane, 4-methylvinylcyclohexane, and 3-methylvinylcyclohexane.

[0055] Such structural units can be formed, for example, by copolymerization of vinylcycloalkane monomers with methacrylic acid ester monomers such as methyl methacrylate. Alternatively, they can be formed by copolymerizing vinylcycloalkene monomers or aromatic vinyl monomers with methacrylic acid ester monomers such as methyl methacrylate to introduce unsaturated alicyclic groups or aromatic rings into the molecular chains, and then hydrogenating them. In the hydrogenation reaction, all carbon-carbon unsaturated bonds, including aromatic rings, are preferably hydrogenated by 80% or more, more preferably 95% or more, and even more preferably 99-100%.

[0056] Examples of vinylcycloalkene monomers used in polymerization include 4-vinylcyclohexene, 4-isopropenylcyclohexene, 1-methyl-4-vinylcyclohexene, 2-methyl-4-vinylcyclohexene, 1-methyl-4-isopropenylcyclohexene, and 2-methyl-4-isopropenylcyclohexene.

[0057] Examples of aromatic vinyl monomers used in polymerization include styrene, α-methylstyrene, α-ethylstyrene, α-propylstyrene, α-isopropylstyrene, α-t-butylstyrene, 2-methylstyrene, 3-methylstyrene, 4-methylstyrene, 2,4-diisopropylstyrene, 2,4-dimethylstyrene, 4-t-butylstyrene, 5-t-butyl-2-methylstyrene, 4-monochlorostyrene, dichlorostyrene, 4-monofluorostyrene, and 4-phenylstyrene.

[0058] The content of alicyclic structural units (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, based on 100% by mass of the methacrylic resin. It is preferable that the content of alicyclic structural units (B-7) be within the above range because it yields a resin with good moldability, heat resistance, optical properties, and low birefringence.

[0059] Other vinyl monomer units (C) copolymerizable with methacrylic acid ester monomer units include acrylic acid ester monomer units (C-1), vinyl cyanide monomer units (C-2), and other monomer units (C-3). These other vinyl monomer units (C) copolymerizable with methacrylic acid ester monomers may be used individually or in combination of two or more.

[0060] The monomer unit (C) can be appropriately selected from materials depending on the properties required for the methacrylic resin of this embodiment. However, if properties such as thermal stability, fluidity, mechanical properties, and chemical resistance are particularly required, at least one selected from the group consisting of acrylic acid ester monomer units (C-1) and vinyl cyanide monomer units (C-2) is preferred.

[0061] As the acrylic acid ester structural unit (C-1) constituting the methacrylic resin, the structural unit represented by the following general formula (7) is preferably used. In the above general formula (7), R １ R represents a hydrogen atom or an alkoxy group having 1 to 12 carbon atoms. ２ This represents an alkyl group with 1 to 18 carbon atoms.

[0062] As monomers for forming the acrylic acid ester monomer unit (C-1) in the methacrylic resin of this embodiment, from the viewpoint of improving weather resistance, heat resistance, fluidity, and thermal stability, methyl acrylate, ethyl acrylate, n-propyl acrylate, n-butyl acrylate, sec-butyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, phenyl acrylate, etc. are preferred, more preferably methyl acrylate, ethyl acrylate, and n-butyl acrylate, and from the viewpoint of availability, methyl acrylate and ethyl acrylate are even more preferred. The acrylic acid ester monomer unit (C-1) may be used alone or in combination of two or more types.

[0063] When using acrylic acid ester monomer units (C-1), the content is preferably 5% by mass or less, and more preferably 3% by mass or less, when the total amount of (A) monomer units and (B) structural units is taken as 100% by mass, from the viewpoint of heat resistance and thermal stability.

[0064] The monomers that make up the vinyl cyanide monomer unit (C-2) constituting the methacrylic resin are not particularly limited, but examples include acrylonitrile, methacrylonitrile, vinylidene cyanide, etc., and among these, acrylonitrile is preferred from the viewpoint of availability and imparting chemical resistance. The vinyl cyanide monomer unit (C-2) may be used alone or in combination of two or more types.

[0065] When vinyl cyanide monomer units (C-2) are used, the content is preferably 15% by mass or less, more preferably 12% by mass or less, and even more preferably 10% by mass or less, when the total amount of (A) monomer units and (B) structural units is taken as 100% by mass, from the viewpoint of solvent resistance and heat resistance retention.

[0066] The monomers forming monomer units (C-3) other than (C-1) and (C-2) that constitute the methacrylic resin are not particularly limited, but examples include amides such as acrylamide and methacrylamide; ethylene glycol or its oligomers such as ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, and tetraethylene glycol di(meth)acrylate, in which both terminal hydroxyl groups of ethylene glycol or its oligomers are esterified with acrylic acid or methacrylic acid; neopentyl glycol di(meth)acrylate and di(meth)acrylate, in which the hydroxyl groups of two alcohols are esterified with acrylic acid or methacrylic acid; polyhydric alcohol derivatives such as trimethylolpropane and pentaerythritol are esterified with acrylic acid or methacrylic acid; and polyfunctional monomers such as divinylbenzene.

[0067] The content of other vinyl monomer units (C) copolymerizable with methacrylic acid ester monomers is preferably 0 to 20% by mass, more preferably 0 to 18% by mass, and more preferably 0 to 15% by mass, based on 100% by mass of the methacrylic resin, from the viewpoint of enhancing the effect of imparting heat resistance by the (B) structural units. In particular, when a crosslinkable polyfunctional (meth)acrylate having multiple reactive double bonds is used 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 fluidity.

[0068] The stereoregularity of the methacrylic resin is not particularly limited to syndiotacticity (rr) and attacticity (mr) as expressed in triplicate notation. Syndiotacticity (rr) is the proportion of two chains (diad) in a triplicate (triad), which is a chain of three consecutive structural units, that are both racemo (rr). Similarly, attacticity (mr) is the proportion of two chains (diad) in a triplicate that are meso and racemo (mr). In polymer molecules, chains of structural units with the same stereoconfiguration are called meso, and those with the opposite stereoconfiguration are called racemo, and are denoted as m and r, respectively.

[0069] The triple-represented syndiotacticity (rr) ratio and attacticity (mr) ratio were determined in deuterated chloroform at 30°C. １ This is obtained by measuring the 1H-NMR spectrum. In this spectrum, with TMS set to 0 ppm, the chemical shift corresponding to syndiotacticity (rr) is observed in the range of 0.6–0.95 ppm, and the chemical shift corresponding to attackiness (mr) is observed in the range of 0.95–1.10 ppm. The ratio of these peak areas to the area in the 0.6–1.35 ppm region is the syndiotacticity (rr) ratio and the attackiness (mr) ratio.

[0070] (Other components) When a thermoplastic resin is used as the material constituting the resin substrate of this embodiment, known or other resins may be included in combination, as long as they can exhibit the properties required for the resin substrate and resin optical element of this embodiment.

[0071] Other resins include, but are not limited to, rubbery polymers such as acrylic rubber, polyethylene resins, polypropylene resins, polystyrene resins, syndiotactic polystyrene resins, polycarbonate resins, ABS resins, acrylic resins, AS resins, BAAS resins, MBS resins, AAS resins, biodegradable resins, polyurethane resins, polycarbonate-ABS resin alloys, polyalkylene arylate resins (polybutylene terephthalate, polyethylene terephthalate, polypropylene terephthalate, polytrimethylene terephthalate, polyethylene naphthalate, etc.), polyamide resins, polyphenylene ether resins, polyphenylene sulfide resins, phenolic resins, etc. The above thermoplastic resins may be used individually or in combination of two or more resins.

[0072] In particular, when used in combination with methacrylic resins, AS resin and BAAS resin are preferred from the viewpoint of improving fluidity, acrylic rubber polymers, ABS resin and MBS resin are preferred from the viewpoint of improving impact resistance, and polyester resin is preferred from the viewpoint of improving chemical resistance. Polycarbonate resins are preferred when it is necessary to impart heat resistance, impact resistance, or adjust optical properties. Furthermore, acrylic resins have good compatibility with the aforementioned methacrylic resins and are preferred when it is necessary to adjust properties such as fluidity and impact resistance while maintaining transparency.

[0073] In the thermoplastic resin used in this embodiment, when the above-mentioned thermoplastic resin is combined with the other resins, the combination should be within a range that allows the effects of the present invention to be expressed. However, considering the effect of imparting properties, the blending ratio of the other resins is preferably 50% by mass or less, more preferably 45% by mass or less, even more preferably 40% by mass or less, even more preferably 30% by mass or less, and particularly preferably 20% by mass or less, based on 100% by mass of the total amount of the thermoplastic resin and the other resins. Furthermore, considering the effect of imparting properties when blending with other resins, the lower limit of the blending amount of the other resins is preferably 0.1% by mass or more, more preferably 1% by mass or more, even more preferably 2% by mass or more, even more preferably 3% by mass or more, and particularly preferably 5% by mass or more. The type and content of the other resins can be appropriately selected according to the effects expected when used in combination with the other resins.

[0074] (Additives) When a thermoplastic resin is used in this embodiment, additives may be optionally added. Additives are not particularly limited as long as they can exert the effects of the present invention, and may be appropriately selected according to the purpose.

[0075] Additives include, but are not limited to, various stabilizers such as UV absorbers, heat stabilizers, and light stabilizers; mold release agents; lubricants; plasticizers; flame retardants; flame retardant aids; curing agents; curing accelerators; antistatic agents; conductivity imparters; stress relaxants; crystallization accelerators; hydrolysis inhibitors; chain length extenders; compatibilizers; nucleating agents; reinforcing materials such as fillers; impact imparters; flow regulators; dyes; sensitizers; colorants; thickeners; settling inhibitors; sagging inhibitors; fillers; defoamers; coupling agents; light-diffusing microparticles; refractive index adjusters; heat absorbers; rust inhibitors; antibacterial and antifungal agents; antifouling agents; conductive polymers, etc.

[0076] When using the aforementioned thermosetting resin and / or active energy ray curing resin, examples include (meth)acrylate resins, epoxy resins, silicone resins, aliphatic allyl carbonate resins, aromatic allyl carbonate resins, polyurethane resins, polythiourethane resins, episulfide resins, polyurea resins, etc. A thiourethane resin refers to a resin having a bond (-NHCOS-, -NHCSO-, -NHSS-) in which at least one oxygen atom of the polyurethane bond (-NHCOO-) in the main chain is replaced by a sulfur atom. As the resin material, a polymerizable component can be suitably used that combines one or more isocyanate components selected from polyisocyanates, polyisothiocyanates, and polyisothiocyanate thioisocyanates with one or more known active hydrogen compound components selected from polythiols and polyols as appropriate. Here, examples of polyisocyanates include aliphatic, alicyclic, aromatic, and their derivatives, as well as those derived from sulfide, polysulfide, or thiocarbonyl (thioketone) derivatives in which sulfur is introduced into part of their carbon chains. From the viewpoint of resistance to yellowing, aliphatic or alicyclic polyisocyanates are preferred. Similarly, examples of polythiols include aliphatic, alicyclic, aromatic, and their derivatives, as well as those derived from sulfide, polysulfide, or polythioethers in which sulfur is introduced into part of their carbon chains. From the viewpoint of resistance to yellowing, aliphatic or alicyclic polythiols are preferred.

[0077] Episulfide resins refer to resins obtained by reacting dithioepoxy compounds, curing agents, and other polymerizable compounds. Known resins obtained by curing linear alkyl sulfide type dithioepoxy compounds can be used. As curing agents, amines, organic acids, or inorganic acids, which are common curing agents for epoxy resins, can be used.

[0078] When using the aforementioned thermosetting resin and / or active energy ray curing resin, antioxidants, ultraviolet absorbers, specific wavelength absorbers, mold release agents, curing agents, molecular weight modifiers, photochromic agents, etc., may be added as needed, to the extent that they do not interfere with the effects of the present invention.

[0079] The glass transition temperature (Tg) of the resin constituting the resin substrate is preferably 105°C to 160°C, more preferably 110 to 155°C, even more preferably 115 to 150°C, and most preferably 120 to 145°C, when a thermoplastic resin is used as the resin. The glass transition temperature can be measured by the midpoint method in accordance with JIS-K7121. A glass transition temperature of 115°C or higher ensures heat resistance even in high-temperature environments such as those generated by electronic devices like VR / AR devices and in some outdoor and automotive environments. It is also preferable from the viewpoint of suppressing cracks in the optical thin film caused by thermal deformation of the resin substrate, as the shape is maintained even at high temperatures. On the other hand, when the glass transition temperature (Tg) is 160°C or lower, melting at extremely high temperatures is unnecessary, thus suppressing thermal decomposition of the resin and other materials, and allowing for the production of a product with a good appearance. The glass transition temperature (Tg) is preferably 155°C or lower, more preferably 150°C or lower, and even more preferably 145°C or lower, in order to obtain the above-mentioned effects even more effectively. Furthermore, when the glass transition temperature exceeds 160°C, it is necessary to maintain a high mold temperature when forming the resin substrate by injection molding in order to improve the shape accuracy of the resin substrate and reduce birefringence. When removing the resin substrate from the mold, a long cooling time is required to suppress deformation such as sink marks, which increases the cycle time. In addition, rapid cooling due to the temperature difference with room temperature can easily leave distortion in the resin substrate, which is undesirable from the standpoint of sufficiently reducing the birefringence of the resin substrate.

[0080] In this embodiment, as described above, the resin optical element is composed of a resin substrate. Here, the part of the resin substrate that forms the substrate, which is made of an organic compound and is the outermost surface layer, is called the "resin surface layer." In other words, the resin surface layer is the surface layer that is in contact with the outside of the resin substrate, and the optical thin film and inorganic oxide film described later are formed on this resin surface layer.

[0081] Furthermore, the resin substrate used in the resin optical element of this embodiment may be a radical-decomposing resin. Thermoplastic resins are classified into radical-decomposing and radical-crosslinking types. When a resin is irradiated with energy rays such as electron beams, X-rays, UV rays, and gamma rays, polymer radicals are generated in the main chain, and in many cases, a crosslinking reaction in which radicals become bonding sites and a decomposition reaction in which radicals become decomposition sites occur simultaneously. At this time, resins in which the crosslinking reaction is more dominant are called radical-crosslinking resins, and resins in which the decomposition reaction is more dominant are called radical-decomposing resins. Such crosslinking and decomposition reactions proceed similarly in the reaction between organic radicals generated by the thermal decomposition of organic peroxides and resins, or in the reaction between a gas plasma-generated by a high-frequency power supply and resins. When a film is formed on a radical-decomposing resin, the electron beam used for film formation or backscattered electrons generated by film formation act on the outermost surface of the resin, generating radicals in the main chain skeleton of the resin and causing a decomposition reaction of the resin, thereby generating a disintegrated and altered layer on the outermost surface of the resin in which brittleness is increased due to the detachment of side chains and a decrease in molecular weight. At this time, the film is formed on top of the disintegrated and altered layer. When measuring film adhesion to a deposited film using known methods such as tape peel tests, there is a problem in that the film adhesion appears poor because the decomposed and altered layer peels off along with the film. In the resin optical element of this embodiment, even with a radical-decomposed resin, a film with good film adhesion can be obtained without causing deterioration of the resin surface. In the decomposition reaction of a radical-decomposed resin, decomposition gas is generated simultaneously with the severance of the main chain and side chains. That is, as a result of the decomposition reaction, some of the structures that made up the resin are desorbed as decomposition gas, so the proportion of elements and bonding modes in the resin changes before and after the decomposition reaction. Therefore, the degree of resin decomposition can be quantified by measuring the changes in the proportion of elements and bonding modes in the resin before and after the decomposition reaction. Examples of methods for measuring such changes include energy-dispersive X-ray spectroscopy (EDS / EDX), X-ray fluorescence analysis (XRF), Auger electron spectroscopy (AES), and X-ray photoelectron spectroscopy (XPS). Among these, X-ray photoelectron spectroscopy is preferred from the viewpoint that information on the proportion of elements and bonding modes (chemical state) can be obtained simultaneously. Preferred analytical methods using X-ray photoelectron spectroscopy will be described later.

[0082] Examples of the radical-decomposing resins include resins that mainly have quaternary and / or tertiary carbon in their main chain, but resins in which decomposition reactions have been experimentally confirmed to proceed predominantly by irradiation with energy rays such as gamma rays and electron beams can also be used. Specifically, examples include methacrylic resins, polycarbonate resins, PET, polyisobutylene, polyalphamethylstyrene, polymethacrylic acid, polymethacrylamide, polymethacrylonitrile, polyvinylidene chloride, cellulose, and tetrafluoroethylene. Among these, since excellent transparency is desirable for optical applications, methacrylic resins and polycarbonate resins are preferred, and from the viewpoint of low birefringence, methacrylic resins are more preferred.

[0083] (Optical Thin Film) In the resin optical element of this embodiment, an optical thin film is formed on at least one of the optically effective surfaces, either directly or via an intervening film such as an inorganic oxide film formed as needed on the surface layer of the resin substrate constituting the optical element. By forming an optical thin film, desired optical properties can be imparted to the resin optical element of this embodiment. In the resin optical elements shown in Figures 1 and 2, optical thin films 12 and 22 are formed on the resin surface layers 14 and 24 via inorganic oxide films 13 and 23.

[0084] The functions of the optical thin film in this embodiment include, for example, anti-reflective, mirror, partial reflection, partial transmission, ultraviolet cut filter, infrared cut filter, bandpass filter, notch filter, edge filter, dichroic mirror, conductive film, etc. Among these, the optical thin film is preferably an anti-reflective film, a partially reflective film, a partially transparent film, or a mirror, and more preferably an anti-reflective film, a partially reflective film, or a partially transparent film. When the optical thin film of this embodiment is deposited adjacent to an inorganic oxide film, it is preferable to design the optical thin film by taking into account the optical properties and thickness of the inorganic oxide film so that the desired optical function is expressed in the overall film configuration combining the inorganic oxide film and the optical thin film.

[0085] When the optical thin film is a partially anti-reflective film or a partially transparent film, it is preferable that the spectral reflectance of the partially reflective film or the partially transparent film is 30% or more and 60% or less in the wavelength range of 450 nm to 650 nm. By having a spectral reflectance of 30% or more and 60% or less, it is possible to obtain the high optical performance required for optical products such as VR and AR, while simultaneously achieving a good balance with film adhesion and crack resistance before and after high temperature and high humidity testing. Note that a spectral reflectance of 30% or more and 60% or less for the partially reflective film or the partially transparent film means that in the target wavelength range, the minimum value of the spectral reflectance curve is 30% or more and the maximum value is 60% or less.

[0086] From a similar viewpoint, it is more preferable that the partial reflective film or the partial transparent film has an average spectral reflectance in the wavelength range of 450 nm to 650 nm that is greater than 30% and less than 60%.

[0087] Furthermore, it is preferable that the difference between the maximum and minimum spectral reflectance values ​​of the partial reflective film or the partial transparent film in the wavelength range of 450 nm to 650 nm is 2% or more and 10% or less. By setting the difference in spectral reflectance to 2% or more and 10% or less, it is possible to obtain sufficient optical performance required for optical products such as VR and AR while maintaining good film adhesion. If the difference between the maximum and minimum spectral reflectance values ​​is less than 2%, the number of multilayer films required will increase, and the total thickness of the multilayer films will increase. This will lead to larger film stresses immediately after deposition and changes in film stress over time, making it difficult to achieve both good film adhesion and crack resistance before and after high-temperature and high-humidity testing. On the other hand, if the difference between the maximum and minimum spectral reflectance values ​​is greater than 10%, film adhesion and crack resistance before and after high-temperature and high-humidity testing will improve, but the precision of the reflectance will decrease, which may reduce the image quality when used as an optical product such as VR or AR.

[0088] The optical thin film in this embodiment may be an inorganic film. Examples of materials for the inorganic film include metal oxides, metal halides, metal nitrides, metal sulfides, etc. Specifically, MgF ２ SiO ２ Low refractive index materials such as Al ２ O ３ SiOｘ (1≦x<2), LaF ３ , Y ２ O ３ , medium refractive index materials such as MgO, Nb ２ O ５ , HfO ２ , ZrO ２ , CEO ２ Ta ２ O ５ ZnS, TiO ２ Examples include high refractive index materials such as SiN and AlN. Mixtures, composite oxides, and oxygen-deficient compounds based on these materials can also be used. Specifically, TiO, Ti ３ O ５ Ti ４ O ７ Ti ２ O ３ Al, available as Merck's Substance M series ２ O ３ -La ２ O ３ TiO2 is available as a mixture, Substance H series. ２ -ZrO ２ mixture, TiO ２ -Pr ６ O １１ mixture, TiO ２ -La ２ O ３ mixture, TiO ２ -Nb ２ O ５ Examples include mixtures. When the optical thin film is a mirror, a partially reflective film, or a partially transparent film, other metals such as silver, aluminum, chromium, and copper can also be used. Furthermore, when the optical thin film is a conductive film, materials such as ITO can also be used.

[0089] When the optical thin film in this embodiment is an inorganic film, the inorganic film can be used as a single layer or multiple layers can be stacked. Furthermore, a structure can be created that has a refractive index gradient from the interface on the resin surface side to the interface on the outside side.

[0090] The optical thin film of this embodiment can be deposited by known methods. Among these, deposition by physical vapor deposition (PVD) is preferred, deposition by vacuum deposition, ion-assisted deposition, ion plating, plasma-assisted deposition, and sputtering is more preferred, and deposition by vacuum deposition, ion-assisted deposition, ion plating, and plasma-assisted deposition is even more preferred. All physical vapor deposition methods are dry deposition methods.

[0091] Vacuum deposition, ion-assisted deposition, ion plating, and plasma-assisted deposition systems consist of a chamber and a deposition source located within the chamber, with the substrate to be deposited held within the chamber. Examples of deposition sources include resistance heating sources and electron beam heating sources.

[0092] Here, a schematic diagram of a typical deposition apparatus is shown in Figure 5. Figure 5(a) is an example of a deposition apparatus having a resistance heating type deposition source, and Figure 5(b) is an example of a deposition apparatus having an electron beam heating type deposition source (electron gun). Although not shown in the figures, it is also possible to use a deposition apparatus that has both a resistance heating type deposition source and an electron beam heating type deposition source.

[0093] In the deposition apparatus 111 shown in Figure 5(a), 112 is the chamber, 113 is the resistance heating power supply, 114 is the deposition dome, 115 is the boat, and 116 is the shutter. The resistance heating power supply 113 and the boat 115 together are called the deposition source. When the boat 115 is heated by the resistance heating power supply 113, the deposition material 117 is heated through the heat and vapor is generated. The generated vapor reaches and deposits on the substrate 118 to be deposited, which is held inside the deposition dome 114, thereby forming a thin film 119 made of the deposition material 117. Multiple boats 115 may be installed inside the deposition apparatus 111, which allows for increasing the film thickness of the same deposition material or depositing multiple deposition materials (not shown).

[0094] The material of the boat 115 is preferably a material with high heat resistance, corrosion resistance, and low vapor pressure, from the viewpoint of preventing contamination with the deposition material 117 and its vapor during the high-temperature heating process under high vacuum, and obtaining the film composition and optical properties of the thin film 119 as designed. Specifically, this includes tungsten, tantalum, molybdenum, and alloy materials based on these. It is also possible to use materials on which a coating for improved corrosion resistance has been applied separately to the surface. The shape of the boat 115 may be selected from the viewpoint of the characteristics of the deposition material used, the thickness of the thin film obtained, the film composition, and the suppression of film defects. Specifically, this includes, but is not limited to, boat-shaped, spiral-shaped, basket-shaped, crucible-shaped, a composite structure of crucible and basket, box-shaped, baffled box-shaped, etc.

[0095] Furthermore, in the deposition apparatus 120 shown in Figure 5(b), 121 is the chamber, 122 is the electron gun, 123 is the electron gun power supply, 124 is the deposition dome, 125 is the crucible, 126 is the pole piece, and 127 is the shutter. The electron gun power supply 123, electron gun 122, and crucible 125 together are called the deposition source. The electron beam 132 generated from the electron gun 122 is deflected by 150° or more (for example, 180°, 270°) by the magnetic field formed by the pole piece 126, and irradiates the deposition material 129 contained inside the crucible 125. When the electron beam 132 irradiates the deposition material 129, the deposition material 129 is heated and vapor is generated. The generated vapor reaches and deposits on the substrate 130 to be deposited, which is held inside the deposition dome 124, thereby forming a thin film 131 made of the deposition material 129. Multiple crucibles 125 are provided on a rotating platform, and by rotating the platform, any crucible can be positioned at the electron beam irradiation location (not shown).

[0096] As described above, when the electron beam 132 is incident on the deposition material 129, some of the irradiated electrons are reflected (backscattered) on the surface of the deposition material 129 due to the input power and material properties, causing a certain amount of backscattered electrons 133 to diverge. When the backscattered electrons 133 repeatedly reflect off the inner wall of the deposition apparatus and reach the substrate 130, resin decomposition (embrittlement of the substrate 130) occurs, causing poor adhesion between the substrate 130 and the thin film 131 (the thin film 131 is more likely to peel off from the embrittlemented portion of the substrate 130). Furthermore, some of the backscattered electrons 133 also wrap around to the back of the deposition dome 124 and reach the back surface of the substrate 130, which is a non-deposited surface. When the backscattered electrons 133 reach the back surface of the substrate 130, resin decomposition (embrittlement of the back surface of the substrate 130) also occurs, causing poor adhesion between the back surface of the substrate 130 and the thin film when the thin film is deposited on the back surface of the substrate 130 in subsequent film deposition. Once the substrate 130 and its back surface become brittle, it is difficult to improve (recover) the poor adhesion in subsequent film deposition.

[0097] While all radical-decomposing resins can cause similar problems, methacrylic resins are particularly susceptible to the effects of backscattered electrons 133 compared to other resins. Therefore, in order to obtain good adhesion, it is necessary to suppress the effects of backscattered electrons 133 on multiple optically effective surfaces, including the film-forming and non-film-forming surfaces of the substrate 130, preferably on all optically effective surfaces. As a countermeasure, it is effective to make it as difficult as possible for backscattered electrons 133 to reach the substrate 130.

[0098] One method to make it difficult for backscattered electrons 133 to reach the substrate 130 is to deposit an inorganic oxide film with sufficient thickness to adequately shield backscattered electrons on multiple optically effective surfaces of the substrate in a manner that does not generate backscattered electrons, before depositing the film that generates backscattered electrons. As a result, even if backscattered electrons 133 generated during the subsequent deposition of the optical thin film are directed toward the substrate 130, the inorganic oxide film acts as a barrier layer, preventing the backscattered electrons from reaching the surface of the substrate 130 (the interface with the inorganic oxide film), thereby suppressing embrittlement of the substrate 130 on the surface where the inorganic oxide film is deposited. In this case, it is preferable that the inorganic oxide film is deposited on one or more optically effective surfaces in addition to the optically effective surface where the backscattered electron-generating film deposition is to be performed first, and it is most preferable that it is deposited on all optically effective surfaces.

[0099] Dry film deposition methods that, in principle, do not generate backscattered electrons include resistance heating deposition, electron beam bombardment indirect heating deposition, and high-frequency induction heating deposition. When depositing the inorganic oxide film of this embodiment, it is preferable to use one of these deposition methods.

[0100] Electron beam bombardment (not shown) is similar to electron beam deposition in that it uses an electron gun power supply, an electron gun, and a crucible as the deposition source, but it differs in that it heats the crucible (liner) by irradiating the back surface of the crucible (liner) filled with deposition material with an electron beam generated from the electron gun. In electron beam bombardment, the electron beam is not directly irradiated onto the deposition material, so in principle, backscattered electrons are not generated.

[0101] The shape of the deposition material used for forming the optical thin film in this embodiment is not particularly limited and can be appropriately selected considering the specifications and characteristics of the deposition apparatus and the availability of the deposition material. Specifically, examples include pellet shape, tablet shape, granular shape, powder, fan shape, ring shape, and rod shape.

[0102] In the deposition of the optical thin film according to this embodiment, values ​​such as the pressure before deposition, pressure during deposition, type and amount of introduced gas, deposition rate, electron beam output, ion assist voltage, ion assist current, neutralizer bias current, ion beam irradiation time, and deposition temperature can be appropriately set.

[0103] In the deposition of optical thin films according to this embodiment, when using ion-assisted deposition, it is preferable to use oxygen gas, argon gas, or a mixture thereof as the introduced gas. The gas introduction amount is preferably 20 to 100 sccm for oxygen gas and 0 to 30 sccm for argon gas. Increasing the gas introduction amount allows for a higher film density of the optical thin film, improving film quality and suppressing optical shift due to moisture adsorption. In the case of increased oxygen gas introduction, it also allows for efficient oxidation of oxygen-deficient compounds. However, excessive gas introduction can lead to problems such as increased film density, increased film stress, increased substrate deformation, cracking, and delamination; a shorter mean free path of vaporized deposition particles, a decrease in deposition rate; and increased energy required to obtain a certain film thickness. Those skilled in the art can set the type and amount of introduced gas to appropriate values ​​according to the composition and refractive index of the target compound.

[0104] The ion assist conditions are preferably such that the ion beam voltage is 100 to 1500 V, more preferably 200 to 1400 V, even more preferably 300 to 1300 V, and particularly preferably 400 to 1200 V. The ion beam current is preferably 50 to 1500 mA, more preferably 100 to 1400 mA, even more preferably 200 to 1300 mA, and particularly preferably 400 to 1200 mA. If the ion beam voltage or ion beam current is below the lower limit of these numerical ranges, the effect of improving the adhesion between the resin substrate and the optical thin film may not be sufficient, or the film density of the optical thin film may decrease, potentially leading to larger changes in film properties due to moisture adsorption over time and during reliability tests. If the ion beam voltage or ion beam current exceeds the upper limit of these numerical ranges, the resin substrate may be damaged, resulting in yellowing of the substrate, delamination or cracking of the film, or the film stress of the optical thin film may increase, resulting in deformation of the substrate or cracking of the film. Those skilled in the art can set the ion-assisted conditions to appropriate values ​​depending on the composition and refractive index of the target compound and the properties of the substrate.

[0105] The refractive index of the inorganic film constituting the optical thin film of this embodiment can be adjusted by changing the pressure during film formation, the type and amount of introduced gas, the film formation rate, the ion-assisted voltage, the ion-assisted current, the plasma gun output, the film formation temperature, etc. Generally, the denser the film produced, the higher the refractive index of the resulting inorganic film. Specifically, the following conditions can be used to increase the refractive index of the inorganic film: In the deposition of oxygen-deficient compounds, change the ratio of the amount of oxygen gas introduced and / or the oxygen partial pressure during film formation to the film formation rate of the deposited material (here, if the refractive index when the deposited material is completely oxidized is greater than that in the oxygen-deficient state, set the amount of oxygen gas introduced and / or the oxygen partial pressure during film formation relatively higher. In the opposite case, set them relatively lower); increase the value of the ion-assisted voltage and / or ion-assisted current in ion-assisted deposition; increase the amount of gas introduced in ion-assisted deposition; increase the output of the plasma gun in ion plating deposition and plasma-assisted deposition; increase the film formation temperature; etc., but are not limited to these. When setting these conditions, a person skilled in the art can set appropriate values ​​according to the composition and refractive index of the target compound and the properties of the substrate.

[0106] When depositing the optical thin film according to this embodiment, the initial pressure (starting vacuum) is 1 × 10⁻⁶ －４ Pa ~ 1 x 10 －２ It is preferable to use Pa. Also, the pressure during film formation should be 1 × 10⁻⁶. －３ Pa ~ 5 x 10 －２ A range of Pa is preferred. Lower pressure during film formation allows for efficient vaporization of the deposition material, from the viewpoint of the vapor pressure of the deposition material. Furthermore, since the mean free path of the vaporized deposition material is increased, a high film formation rate can be obtained even when the energy supplied to the deposition material is small. On the other hand, when performing reactive deposition using oxygen-deficient compounds as the deposition material, if the partial pressure of the reacting gas (oxygen, nitrogen, etc.) is low, the reaction rate decreases, making it impossible to obtain the desired composition, or productivity may actually worsen by reducing the film formation rate to compensate for the reaction rate. Considering these points, it is preferable to appropriately set the pressure during film formation depending on the deposition material, the type of introduced gas, and whether or not reactive deposition is performed.

[0107] When depositing the optical thin film in this embodiment, the deposition rate is preferably 0.1 to 100 Å / sec, more preferably 0.5 to 50 Å / sec, and even more preferably 1 to 30 Å / sec. A higher deposition rate shortens the deposition cycle time and improves productivity, but makes precise control of the film thickness difficult. Furthermore, when performing reactive deposition using oxygen-deficient compounds or the like as the deposition material, it is necessary to appropriately set the partial pressure of the reaction gas (oxygen, nitrogen, etc.) and the deposition rate according to the composition of the deposition material and the composition of the desired film. The value of the deposition rate may be set as appropriate depending on the deposition material, the type of gas introduced, whether or not reactive deposition is performed, and the desired film composition and film thickness precision.

[0108] When depositing the optical thin film of this embodiment onto multiple optically effective surfaces, it is preferable to keep the exposure time to the atmosphere as short as possible when switching the deposition surface from one surface to another. More specifically, it is preferable to keep it within 24 hours, more preferably within 12 hours, even more preferably within 6 hours, particularly preferably within 3 hours, and especially preferably within 1 hour. Furthermore, as disclosed in Japanese Patent Application Publication No. 3-294481, the exposure time to the atmosphere can be reduced to zero by using a deposition apparatus having an automatic substrate reversal mechanism.

[0109] (Inorganic Oxide Film) As shown in Figures 1, 2, and 3, in the resin optical element of this embodiment, it is preferable that an inorganic oxide film is formed adjacent to the resin surface layer on multiple optically effective surfaces, and it is more preferable that the film is formed on all optically effective surfaces. This is to prevent backscattered electrons generated during the subsequent formation of the optical thin film from reaching the resin surface layer and to suppress the embrittlement of the resin surface layer caused by the influence of backscattered electrons. Furthermore, the inorganic oxide film has the function of improving film adhesion between the resin substrate and the optical thin film, and also functions as a buffer layer to alleviate stress caused by the difference in expansion rates between the resin substrate and the optical thin film in high temperature and high humidity environments, thereby suppressing the occurrence of cracks in the optical thin film. Here, being formed adjacent to the resin surface layer means that, as shown in Figures 1 to 3, a coating layer (here, inorganic oxide films 13, 23, 33) is directly formed on the resin surface layers 14, 24, 34.

[0110] The inorganic oxide film preferably contains one or more elements selected from silicon, aluminum, titanium, hafnium, zirconium, tantalum, cerium, and niobium; more preferably contains one or more elements selected from silicon, aluminum, titanium, and zirconium; even more preferably contains silicon; particularly preferably is a silicon oxide; and most preferably is SiOx (1 < x < 2).

[0111] Here, the inorganic oxide film may be a single layer or a laminate of multiple layers. Furthermore, it may have a structure that has a refractive index gradient from the interface with the resin surface to the interface facing the outside.

[0112] Furthermore, the thickness of the inorganic oxide film is preferably such that it can sufficiently shield backscattered electrons, and this can be calculated by Monte Carlo simulation. Specifically, it is preferably 300 nm or more, more preferably 305 nm or more, even more preferably 310 nm or more, even more preferably 315 nm or more, and even more preferably 320 nm or more. If the thickness is greater than or equal to the above values, even if backscattered electrons generated during the formation of the optical thin film reach the substrate, the penetration of backscattered electrons stops inside the inorganic oxide film, and the backscattered electrons do not reach the surface of the substrate (interface with the inorganic oxide), thereby suppressing the deterioration of the resin surface layer beneath the inorganic oxide film. Furthermore, the thickness of the inorganic oxide film is preferably 2000 nm or less, more preferably 1600 nm or less, even more preferably 1200 nm or less, even more preferably 1000 nm or less, even more preferably 800 nm or less, even more preferably 600 nm or less, even more preferably 500 nm or less, even more preferably 470 nm or less, especially preferably 440 nm or less, particularly preferably 420 nm or less, and especially preferably 400 nm or less. A thickness of less than or equal to the above values ​​is preferable from the viewpoint of ease of optical design, precision of optical design, productivity, and economics.

[0113] Furthermore, it is preferable that the inorganic oxide is deposited on multiple optically effective surfaces, and more preferably on all optically effective surfaces.

[0114] In addition, an optical film may be laminated adjacent to the inorganic oxide film. Examples of the optical film include polarizers, waveplates, and phase difference plates.

[0115] The inorganic oxide film in this embodiment is formed by a film formation method that, in principle, does not generate backscattered electrons, and a dry film formation method is preferred. Specifically, it is preferable to form an inorganic oxide film with a thickness of 300 nm or more on multiple optical effective surfaces, preferably all optical effective surfaces, by resistance heating deposition and / or electron beam bombardment indirect heating deposition. As a result, as shown in Figure 5(b), even if backscattered electrons 133 generated during the subsequent formation of the optical thin film are directed toward the substrate 130, the inorganic oxide film acts as a barrier layer and does not reach the surface of the substrate (interface with the inorganic oxide film), thereby suppressing embrittlement of the substrate 130. Furthermore, it is preferable to form an inorganic oxide film with sufficient thickness on multiple optical effective surfaces of the substrate using a method that does not generate backscattered electrons before performing film formation that generates backscattered electrons, and it is more preferable to perform the film formation on all optical effective surfaces. If the film is not formed under these conditions, backscattered electrons 133 are more likely to reach the substrate 130 on optical effective surfaces where the inorganic oxide film is not formed or is of insufficient thickness, and embrittlement progresses on the surface layer of the optical effective surface, making it impossible to obtain good film adhesion.

[0116] Furthermore, methods for depositing inorganic oxide films that, in principle, do not generate backscattered electrons include resistance heating deposition and electron beam bombardment indirect heating deposition. When depositing the inorganic oxide film in this embodiment, it is preferable to use one of these deposition methods.

[0117] The shape of the deposition material used for forming the inorganic oxide film in this embodiment is not particularly limited and can be appropriately selected considering the specifications and characteristics of the deposition apparatus and the availability of the deposition material. Specifically, examples include pellet shape, tablet shape, granular shape, powder, fan shape, ring shape, and rod shape.

[0118] In the deposition of inorganic oxide films according to this embodiment, values ​​such as the pressure before deposition, the pressure during deposition, the type and amount of introduced gas, the deposition rate, the voltage applied to the boat, the electron beam output, and the deposition temperature can be set as appropriate.

[0119] When ion-assisted deposition is performed in the deposition of the inorganic oxide film according to this embodiment, there is a possibility that the resin substrate may be damaged, resulting in yellowing of the substrate, delamination and cracking of the film, or deformation and cracking of the substrate due to increased film stress of the inorganic oxide film. In addition, the flexibility of the inorganic oxide decreases as the film density increases, and the effect of mitigating stress caused by the difference in expansion rates between the resin substrate and the optical thin film in high temperature and high humidity environments may not be sufficiently obtained. In particular, when the resin substrate is a radical-decomposing resin, decomposition and embrittlement of the substrate due to ion-assisted deposition is likely to occur significantly. For this reason, when depositing the inorganic oxide film according to this embodiment, it is preferable to perform the deposition using a normal vacuum deposition method without ion-assisted deposition.

[0120] The refractive index of the inorganic film constituting the inorganic oxide film of this embodiment can be adjusted by changing the pressure during film formation, the type and amount of introduced gas, the film formation rate, the boat applied voltage, the electron beam output, the film formation temperature, etc. In particular, when the inorganic oxide film of this embodiment is formed using an oxygen-deficient compound such as SiO as the deposition material, it is preferable to adjust the refractive index by adjusting the amount of oxygen gas introduced and / or the pressure during film formation to control the degree of oxidation of the resulting inorganic film.

[0121] When the inorganic oxide film of this embodiment is formed using an oxygen-deficient compound as the deposition material, the amount of oxygen gas introduced is preferably 20 to 300 sccm, more preferably 30 to 280 sccm, and particularly preferably 40 to 250 sccm. The pressure during film formation is 1.0 × 10⁻⁶. －３ Pa ~ 5 x 10 －２A range of Pa is preferred, and it can be set as appropriate to a value higher than the initial pressure (starting vacuum). As the amount of oxygen gas introduced or the pressure during film formation increases, the degree of oxidation of the oxygen-deficient compound increases. In particular, when SiO is used as the deposition material, increasing the amount of oxygen gas introduced or the pressure during film formation increases the degree of oxidation, and the refractive index of the resulting film decreases. When the inorganic oxide film in this embodiment is silicon oxide (SiOx (1 < x ≤ 2)), the refractive index is preferably 1.45 to 1.64, more preferably 1.46 to 1.62, even more preferably 1.47 to 1.61, particularly preferably 1.48 to 1.60, and especially preferably 1.49 to 1.59. Here, the refractive index values ​​are shown at 550 nm (the same applies hereinafter).

[0122] When forming the inorganic oxide film in this embodiment, the initial pressure (initial vacuum) is 1 × 10⁻⁶. －４ Pa ~ 1 x 10 －２ It is preferable to use Pa. Also, the pressure during film formation is 1.0 × 10⁻⁶ as described above. －３ Pa ~ 5 x 10 －２ A range of Pa is preferred. Lower pressure during film formation allows for efficient vaporization of the deposition material, from the viewpoint of the vapor pressure of the deposition material. Furthermore, since the mean free path of the vaporized deposition material increases, a high film formation rate can be obtained even with less energy. On the other hand, when performing reactive deposition using oxygen-deficient compounds as the deposition material, if the partial pressure of the reacting gas (oxygen, nitrogen, etc.) is low, the reaction rate decreases, making it impossible to obtain the desired composition, or productivity may actually worsen by reducing the film formation rate to compensate for the reaction rate. Considering these points, it is preferable to appropriately set the pressure during film formation depending on the deposition material, the type of introduced gas, and whether or not reactive deposition is performed.

[0123] When forming the inorganic oxide film of the present embodiment, the film formation rate is preferably 0.1 to 100 Å / sec, more preferably 0.5 to 50 Å / sec, and still more preferably 1 to 30 Å / sec. A higher film formation rate results in shorter film formation tact time and improved productivity, but makes precise control of film thickness difficult. In addition, when reactive vapor deposition is performed using an oxygen-deficient compound or the like as a vapor deposition material, it is necessary to appropriately set the partial pressure of a reaction gas (oxygen, nitrogen, etc.) and the film formation rate in accordance with the composition of the vapor deposition material and the composition of the desired film. The value of the film formation rate may be appropriately set according to the vapor deposition material, the type of introduced gas, the presence or absence of reactive vapor deposition, the desired film composition, and the required film thickness precision.

[0124] When forming the inorganic oxide film of the present embodiment on a plurality of optically effective surfaces, it is preferable that the exposure time to the atmosphere for switching the film formation surface from one surface to another after forming a film on one surface is as short as possible. If the exposure time to the atmosphere is long, the previously formed inorganic oxide film adsorbs moisture in the air, which may reduce the adhesion of an optical thin film formed on the inorganic oxide film, or the inorganic oxide film may react with oxygen in the air to change the film composition and refractive index, making it impossible to obtain designed optical properties. More specifically, the exposure time to the atmosphere is preferably within 24 hours, more preferably within 12 hours, still more preferably within 6 hours, particularly preferably within 3 hours, and most preferably within 1 hour. In addition, as disclosed in Japanese Unexamined Patent Application Publication No. Hei 3-294481, the exposure time to the atmosphere can also be reduced to zero by using a vapor deposition apparatus having an automatic substrate reversing mechanism.

[0125] (X-ray Photoelectron Spectroscopy) In the first resin optical element of the present embodiment, the surface layer deterioration index on the tape-side peeled surface of the resin base material measured by X-ray photoelectron spectroscopy (I ｓｕｒｆ / I ｉｎｔ ) satisfies the following relationship: 0.8 ≤ I ｓｕｒｆ / I ｉｎｔ ≤ 1 (where, I ｓｕｒｆ is the normalized intensity of the peak derived from C=O bonds in the surface layer of the resin base material, and I ｉｎｔ).) is satisfied. In the second resin optical element of the present embodiment, the surface layer deterioration index (I ｓｕｒｆ / I ｉｎｔ ) on the substrate-side peeled surface of the resin base material measured by X-ray photoelectron spectroscopy satisfies the following relationship: 0.80 ≦ I ｓｕｒｆ / I ｉｎｔ ≦ 1.00. In the second resin optical element of the present embodiment, the surface layer deterioration index I ｓｕｒｆ / I ｉｎｔ ) on the tape-side peeled surface of the resin base material on the optically effective surface measured by X-ray photoelectron spectroscopy satisfies the following relationship: 0.70 ≦ I ｓｕｒｆ / I ｉｎｔ ≦ 1.00 (wherein, the normalized intensity of the peak derived from C=O bonds in the surface layer of the resin base material is I ｓｕｒｆ , and the normalized intensity of the peak derived from C=O bonds in the resin base material is I ｉｎｔ ). It is preferable that the above requirement is satisfied. The above I ｉｎｔ and I ｓｕｒｆ are normalized intensity ratios of peaks derived from C=O bonds when the narrow scan spectrum obtained by X-ray photoelectron spectroscopy focusing on the electron state of the 1s orbital of carbon atoms in the resin base material and the surface layer thereof is normalized by the peak intensity derived from C-C bonds. More specifically, I ｉｎｔ refers to the normalized intensity ratio at a position 5 µm deep from the surface layer of the resin base material. I ｓｕｒｆ refers to the normalized intensity ratio on a peeled surface obtained by peeling a tape described below (hereinafter referred to as "tape peeled surface").

[0126] The surface layer deterioration index (I ｓｕｒｆ / I ｉｎｔThe numerical value represented by ) indicates the degree of deterioration of the resin surface due to decomposition, oxidation, etc., caused by backscattered electrons colliding with the resin surface, as described above. The surface deterioration index changes as new C=O bonds are formed in the polymer or C=O bonds in the polymer are removed due to the deterioration. When the resin substrate contains a radical-decomposing resin with quaternary carbon in the main chain, cleavage of the quaternary carbon causes breakage and oxidation of the main chain and removal of side chains, leading to substrate embrittlement and generation of decomposition gases. In particular, when the side chains bonded to the quaternary carbon contain C=O bonds, the removal of side chains is observed as a decrease in peak intensity originating from the C=O bonds. Therefore, when the surface deterioration index satisfies the above relationship, the damage to the resin surface from backscattered electrons during the optical thin film formation process is sufficiently small, substrate deterioration and embrittlement are suppressed, and the resin surface and the interior of the resin optical element have equivalent chemical structures, resulting in good adhesion between the optical thin film or inorganic oxide film formed on the resin substrate and the resin surface. From the above viewpoint, the surface degradation index at the tape-side peeling surface of the first resin optical element is 0.85 ≤ I ｓｕｒｆ / I ｉｎｔ It is preferable that ≤ 1.00 is satisfied, and 0.90 ≤ I ｓｕｒｆ / I ｉｎｔ It is more preferable that ≤ 1.00 is satisfied, and 0.95 ≤ I ｓｕｒｆ / I ｉｎｔ It is particularly preferable that the condition ≤ 1.00 is satisfied. The surface degradation index at the substrate-side delamination surface of the second resin optical element is 0.82 ≤ I ｓｕｒｆ / I ｉｎｔ Preferably, ≤ 1.00 is satisfied, and 0.84 ≤ I ｓｕｒｆ / I ｉｎｔ Preferably, the condition ≤ 1.00 is satisfied, and 0.86 ≤ I ｓｕｒｆ / I ｉｎｔ Preferably, the condition ≤ 1.00 is satisfied, and 0.88 ≤ I ｓｕｒｆ / I ｉｎｔ It is preferable that ≤ 1.00 is satisfied, and 0.90 ≤ I ｓｕｒｆ / I ｉｎｔ It is more preferable that ≤ 1.00 is satisfied, and 0.91 ≤ I ｓｕｒｆ / I ｉｎｔ It is even more preferable that ≤ 1.00 is satisfied, and 0.92 ≤ I ｓｕｒｆ / I ｉｎｔIt is even more preferable that ≤ 1.00 is satisfied, and 0.93 ≤ I ｓｕｒｆ / I ｉｎｔ It is even more preferable that ≤ 1.00 is satisfied, and 0.94 ≤ I ｓｕｒｆ / I ｉｎｔ It is even more preferable that ≤ 1.00 is satisfied, and 0.95 ≤ I ｓｕｒｆ / I ｉｎｔ It is particularly preferable that the condition ≤ 1.00 is satisfied. The surface degradation index on the tape-side peeling surface of the second resin optical element is 0.75 ≤ I ｓｕｒｆ / I ｉｎｔ It is preferable that ≤ 1.00 is satisfied, and 0.80 ≤ I ｓｕｒｆ / I ｉｎｔ It is preferable that ≤ 1.00 is satisfied, and 0.82 ≤ I ｓｕｒｆ / I ｉｎｔ Preferably, ≤ 1.00 is satisfied, and 0.84 ≤ I ｓｕｒｆ / I ｉｎｔ Preferably, the condition ≤ 1.00 is satisfied, and 0.86 ≤ I ｓｕｒｆ / I ｉｎｔ Preferably, the condition ≤ 1.00 is satisfied, and 0.88 ≤ I ｓｕｒｆ / I ｉｎｔ It is preferable that ≤ 1.00 is satisfied, and 0.90 ≤ I ｓｕｒｆ / I ｉｎｔ It is more preferable that ≤ 1.00 is satisfied, and 0.91 ≤ I ｓｕｒｆ / I ｉｎｔ It is even more preferable that ≤ 1.00 is satisfied, and 0.92 ≤ I ｓｕｒｆ / I ｉｎｔ It is even more preferable that ≤ 1.00 is satisfied, and 0.93 ≤ I ｓｕｒｆ / I ｉｎｔ It is even more preferable that ≤ 1.00 is satisfied, and 0.94 ≤ I ｓｕｒｆ / I ｉｎｔ It is even more preferable that ≤ 1.00 is satisfied, and 0.95 ≤ I ｓｕｒｆ / I ｉｎｔIt is particularly preferable that the value be ≤ 1.00. Due to the depth to which backscattered electrons penetrate, the degree of deterioration of the resin substrate is greater the closer it is to the surface of the resin part. Therefore, the value obtained by subtracting the surface deterioration index on the tape side peeling surface from the surface deterioration index on the substrate side peeling surface is preferably 0.22 or less, more preferably 0.21 or less, even more preferably 0.20 or less, even more preferably 0.19 or less, even more preferably 0.18 or less, still preferably 0.17 or less, and even more preferably 0.16 or less. Also, it is preferable that it be 0 or more. When the difference in the surface deterioration index is within the above range, the degree of deterioration of the resin closer to the surface is small, which is preferable from the viewpoint of good adhesion between the optical thin film or inorganic oxide film formed on the resin substrate and the surface of the resin part.

[0127] When the number of optically effective surfaces of the resin optical element of this embodiment is m surfaces, it is preferable that the number of optically effective surfaces that satisfy the above relationship is two or more, with m surfaces being the most preferable. In particular, when optical thin films are deposited on multiple optically effective surfaces or optical films are laminated to them, it is preferable that the above relationship is satisfied on those surfaces. When the above relationship is satisfied, the adhesion of the optical thin films or optical films on those surfaces is good, and resistance to peeling and cracking in high temperature and high humidity tests is good. On the other hand, when the optically effective surfaces are used with the resin surface layer exposed, without any optical thin film deposition or optical film lamination on their surfaces, the above relationship may or may not be satisfied on those surfaces.

[0128] Here, X-ray photoelectron spectroscopy focusing on the electronic state of the 1s orbital of the carbon atom can be performed by narrow-scan analysis under the following measurement conditions: -Spectrum acquisition conditions- ・Equipment used: ULVAC-PHI VersaProbe II ・Excitation source: Monochromatic Al Kα 15kV × 3.3mA ・Analysis size: Approximately 200μmφ ・Photoelectron extraction angle: 45 degrees ・Pass energy: 117.4eV (Survey), 46.95eV (Narrow) ・Charge correction: C1s = 284.6eV (Surface cleaning conditions) ・Ion species: Ar+ ・Acceleration voltage: 5kV ・Sample current: 20nA ・Raster size: 3mm × 3mm ・Sputtering time: 30 seconds

[0129] In the narrow-scan spectrum obtained by the aforementioned narrow-scan analysis, the charge correction was applied so that the peak originating from the C-C bond was 284.6 eV. At this time, the peaks observed in the range of 288.0 to 289.0 eV are the peaks originating from the C=O bond. In this case, the normalized intensity (I) of the C=O bond originating peak (I) was defined as the value obtained by dividing the C=O bond originating peak intensity (B) by the C=C bond originating peak intensity (A) (B / A).

[0130] Normalized intensity I of peaks originating from C=O bonds in the surface layer of the resin part ｓｕｒｆ Sample pretreatment for measurement can be carried out by the following method (I).

[0131] Method (I): First, a grid-like pattern of cuts consisting of approximately 1 mm x 1 mm squares is formed on the optically effective surface using a cutter. Tape (LP-24, manufactured by Nichiban Co., Ltd.) is applied to the grid-like cuts, rubbed well with the spatula part of a spatula, and then the tape is peeled off quickly. This causes part or all of the optical thin film and / or inorganic oxide film that had formed on the optically effective surface to be taken off by the adhesive of the tape, resulting in film delamination. The newly formed surface due to film delamination is designated as the delamination surface (tape side and substrate side). The tape with the delaminated film etc. attached is used as the measurement sample for the delamination surface on the tape side. The substrate portion that has been successfully delaminated is masked with weighing paper to prevent contamination of the delamination surface, and cut out to a size of approximately 4 mm square with a band saw to be used as the measurement sample for the delamination surface on the substrate side. Next, both the substrate side and the tape side measurement samples are covered with a 2 mmφ Mo mask and measured. If the resin is continuously irradiated with X-rays, the resin may be damaged by the X-rays, and the C=O intensity may gradually decrease. Normalized intensity I of the peak originating from the C=O bond, while minimizing damage caused by X-ray irradiation. ｓｕｒｆ To evaluate this, the measurement is performed using the following procedure: (1) Without adjusting the height (z-align), the measurement is performed with the previously confirmed optimal z value (z = 17.85) fixed. At this time, a recess holder and Mo mask are used. (2) First, the C 1s spectrum is measured in about 5 minutes, and then the remaining Narrow scan and Survey scan are performed. X-ray photoelectron spectroscopy analysis is performed on the peeled surfaces of the tape side and the substrate side using the above procedure, and the obtained C1s spectrum is subjected to three-point leveling using a binary algorithm with the analysis software MaltiPak, and then the normalized intensity of the peak originating from the C=O bond is read, and I ｓｕｒｆ Let's assume that.

[0132] Normalized intensity I of the peak originating from the C=O bond at a depth of 5 μm from the surface of the resin part ｉｎｔ The sample pretreatment for measurement can be carried out as follows. First, the surface side of the optically effective surface is cut parallel with a microtome to expose the surface to a depth of 5 μm ± 1 μm from the resin surface. The normalized intensity (I) of the C=O bond-derived peak obtained by performing X-ray photoelectron spectroscopy analysis on the exposed surface using the same procedure as described above is taken as I. ｉｎｔLet's assume that.

[0133] <Articles using resin optical elements> The resin optical elements of this embodiment may be used in combination with a housing as needed. The resin optical elements of this embodiment can be suitably used as optical components in household goods, office automation equipment, AV equipment, battery electrical components, lighting equipment, automobile parts, etc.

[0134] One example of an article for which this technology is preferably used is a lens for a VR (Virtual Reality) head-mounted display (HMD). Since a head-mounted display is an image display device worn on the head, it is required to be small, lightweight, and cause minimal discomfort when worn. As a means of miniaturization, a method has been proposed in which a quarter-wave plate and a reflective polarizer are combined with the lens, and the polarization state of the light after passing through the lens is changed to switch between reflection and transmission, thereby causing the image to pass through a single lens one and a half times (U.S. Patent No. 6,563,638, Japanese Patent Application Publication No. 2017-21321, etc.).

[0135] The above method works as follows: A quarter-wave plate and a reflective polarizer are placed behind a lens with a partially reflective coating on its front surface. Light incident from the front of the lens as circularly polarized light is converted to linearly polarized light by the quarter-wave plate after passing through the lens. This linearly polarized light is reflected by the reflective polarizer and converted again to the opposite circularly polarized light by the quarter-wave plate, then incident on the lens from the back and reaches the partially reflective coating on the front surface. The light reflected by the partially reflective coating exits the back of the lens, becomes linearly polarized light with a 90° different direction from the initial light, passes through the reflective polarizer, and enters the eye as an image. In this way, a high magnification and wide field of view can be obtained even with a thin optical module. If the polarization state changes while passing through the lens, for example, some light will pass through the reflective polarizer after passing through the lens for the first time, resulting in the overlap of low-magnification and high-magnification images, making it difficult to obtain a clear image. Therefore, low birefringence lenses are required. Furthermore, changes in lens shape due to humidity fluctuations during use are undesirable for improving image quality. Therefore, there is a need for lenses with low hygroscopicity and high shape stability in high-temperature, high-humidity environments.

[0136] Optical components used in household goods, office automation equipment, AV equipment, battery and electrical components, lighting equipment, etc. include, for example, light guide plates, display front panels, and touch panels used in displays of smartphones, PDAs, tablet PCs, and LCD TVs; lenses and prisms used in smartphone and tablet PC cameras, and in telephoto cameras (periscope cameras) with bent optical systems; optical components used in VR (virtual reality) / AR (augmented reality) / MR (mixed reality) / XR (cross reality) head-mounted displays, LCD projectors, and near-infrared sensors (LiDAR; Light Detection and Ranging), such as prism elements, waveguides, freeform light guide members, lenses, especially small, thin, and variable-thickness optical lenses; optical fibers, optical fiber coating materials, optical communication lenses and prisms, lenses, Fresnel lenses, phase plates equipped with microlens arrays, optical cover components, substrates constituting polarization separation elements, polarizers and phase difference films and substrates to which they are bonded, and lenses.

[0137] Examples of optical components in automotive parts include: light guide plates for in-vehicle displays; optical covers made of front panels or curved molded bodies used in in-vehicle meter panels, instrument clusters, car navigation systems, information displays, rear-seat displays, etc.; lenses, prisms, optical direction conversion elements, waveguides, light guides, combiners, dustproof sheets, optical cover components, etc. used in head-up displays; in-vehicle camera lenses (especially front lenses); and light guide rods. In addition to the above, they can also be preferably used in camera focusing plates and components for digital signage display devices that transmit information to network-connected thin displays for advertising and promotional purposes in outdoor locations, stores, public institutions, transportation facilities, etc.

[0138] The present invention will be specifically described below with reference to examples and comparative examples. However, the present invention is not limited to the following examples. The raw materials used in the manufacturing examples are as follows.

[0139] [Monomers] Methyl methacrylate (MMA): Manufactured by Asahi Kasei Corporation; N-phenylmaleimide (phMI): Manufactured by Nippon Shokubai Co., Ltd.; N-cyclohexylmaleimide (chMI): Manufactured by Nippon Shokubai Co., Ltd.; 2-(hydroxymethyl)methyl acrylate (RHMA): Manufactured by Combi-Blocks; Styrene (St): Manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.; Methyl acrylate: Manufactured by Tokyo Chemical Industry Co., Ltd.

[0140] [Organic solvents] ・Metaxylene (mXy): Manufactured by Mitsubishi Gas Chemical Corporation ・Toluene: Manufactured by Fujifilm Wako Pure Chemical Industries, Ltd. ・Methyl isobutyrate: Manufactured by Kanto Chemical Co., Ltd.

[0141] [Polymerization Initiators] ・1,1-di(t-butylperoxy)cyclohexane: Manufactured by NOF Corporation, Perhexa C・t-amyl peroxyisononanoate: Manufactured by Arkema Yoshitomi Co., Ltd., Luperox 570 ・t-amyl peroxy-2-ethylhexanoate: Manufactured by Arkema Yoshitomi Co., Ltd., Luperox 575 ・t-butylperoxy-2-ethylhexanoate: Manufactured by NOF Corporation, Perbutyl O

[0142] [Chain transfer agent] ・n-octyl mercaptan: Manufactured by Chevron Philips Chemicals

[0143] [Other Additives, etc.] ・Stearyl phosphate: Manufactured by Sakai Chemical Industry Co., Ltd., Phoslex A-18 ・Monomethylamine: Manufactured by Mitsubishi Gas Chemical Corporation ・Dimethyl carbonate: Manufactured by Fujifilm Wako Pure Chemical Corporation ・Triethylamine: Manufactured by Fujifilm Wako Pure Chemical Corporation ・Pd / C: Manufactured by NE Chemcat Co., Ltd. ・Rikemar H-100: Manufactured by Riken Vitamin Co., Ltd. ・Tricalcium phosphate: Manufactured by Nippon Chemical Industrial Co., Ltd. ・Calcium carbonate: Manufactured by Shiraishi Industries Co., Ltd. ・Sodium lauryl sulfate: Manufactured by Fujifilm Wako Pure Chemical Corporation

[0144] (Manufacturing Example 1: Methacrylic Resin A) 358.6 kg of methyl methacrylate (hereinafter referred to as MMA), 29.4 kg of N-phenylmaleimide (hereinafter referred to as phMI), 67.7 kg of N-cyclohexylmaleimide (hereinafter referred to as chMI), 0.77 kg of n-octyl mercaptan as a chain transfer agent, and 224.3 kg of metaxylene (hereinafter referred to as mXy) ​​were weighed out and placed in a 1.25 m² chamber equipped with a jacketed temperature control device and stirring blades. ３The mixture was added to the reactor and stirred to obtain a mixed monomer solution. Next, 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 supplemental mixed monomer solution. Dissolved oxygen was removed from the contents of the reactor by bubbling with nitrogen at a rate of 30 L / min for 1 hour, and from Tank 1 by bubbling with nitrogen at a rate of 10 L / min for 30 minutes. Then, steam was blown into the jacket to raise the solution temperature in the reactor to 115°C, and polymerization was started by adding a polymerization initiator solution, which consisted of 0.470 kg of 1,1-di(t-butylperoxy)cyclohexane dissolved in 1.905 kg of mXy, at a rate of 1.0 kg / hour while stirring at 50 rpm. During polymerization, the solution temperature in the reactor was controlled to 115 ± 2°C by temperature control using the jacket. Thirty minutes after the start of polymerization, the rate of addition of the initiator solution was reduced to 0.5 kg / hour. Furthermore, from one hour after the start of polymerization, the entire amount of the additive mixed monomer solution was added from tank 1 at a constant rate over a period of four hours. Additionally, the rate of addition of the initiator solution was reduced to 0.25 kg / hour 3.5 hours after the start of polymerization, and the addition was stopped 5 hours after the start of polymerization. After 12 hours from the start of polymerization, a polymer solution containing a methacrylic resin having a ring structure in the main chain was obtained, and polymerization was completed. This polymer solution was supplied to a concentration apparatus consisting of a tubular heat exchanger and a vaporization tank preheated to 250°C for defoliation. The vacuum level in the vaporization tank was set to 10-15 Torr. The resin flowing down the vaporization tank was discharged with a gear pump, extruded from a strand die, water-cooled, and pelletized to obtain methacrylic resin A. Upon examination of the composition of the obtained pelletized polymer, it was found that the structural units derived from the MMA, phMI, and chMI monomers accounted for 81.0% by mass, 6.6% by mass, and 12.4% by mass, respectively. The weight-average molecular weight was 108,000, the Mw / Mn ratio was 2.04, and the glass transition temperature was 134°C.

[0145] (Manufacturing Example 2: Methacrylic Resin B) A glutarimidated resin was produced using a 15 mm diameter interlocking co-rotating twin-screw extruder, with a molecular weight of 100,000 (styrene content 8% by mass) as the raw material resin and monomethylamine as the imidizing agent. The temperature of each temperature control zone was set to 230-250°C, and the screw rotation speed was 150 rpm. Methyl methacrylate-styrene copolymer (hereinafter also referred to as "MS resin") was supplied at 2 kg / hr, and after the resin was melted and filled using a kneading block, 8 parts by mass of monomethylamine were injected into the resin from the nozzle. A reverse flight was placed at the end of the reaction zone to fill it with resin. By-products and excess monomethylamine after the reaction were removed by reducing the pressure at the vent port to -0.092 MPa. The resin, which emerged as strands from a die at the extruder outlet, was cooled in a water bath and then pelletized in a pelletizer to obtain glutarimidated MS resin intermediate (1). Next, a 15 mm diameter, meshing, co-rotating twin-screw extruder was set to a temperature of 230°C in each temperature control zone and a screw rotation speed of 150 rpm. The glutarimidated MS resin intermediate (1) obtained from the hopper was supplied at a rate of 1 kg / hr, and the resin was melted and filled using a kneading block. Then, a mixture of 0.8 parts by mass of dimethyl carbonate and 0.2 parts by mass of triethylamine was injected into the resin from the nozzle to reduce the number of carboxyl groups in the resin. A reverse flight was placed at the end of the reaction zone to fill it with resin. By-products and excess dimethyl carbonate after the reaction were removed by reducing the pressure at the vent port to -0.092 MPa. The resin, which emerged as strands from a die at the extruder outlet, was cooled in a water bath and then pelletized in a pelletizer to obtain glutarimidated MS resin intermediate (2). Furthermore, glutarimidated MS resin intermediate (2) was fed into a 15 mm diameter, mesh-type, co-rotating twin-screw extruder under the conditions of a set temperature of 230°C in each temperature control zone of the extruder, a screw rotation speed of 150 rpm, and a feed rate of 1 kg / hr. The pressure at the vent port was reduced to -0.095 MPa to remove volatile components such as unreacted adjuncts.The defolable imide resin, which emerged as strands from a die at the outlet of the extruder, was cooled in a water bath and then pelletized in a pelletizer to obtain methacrylic resin B (glutarimide MS resin). The weight-average molecular weight of methacrylic resin B was 85,000, Mw / Mn was 1.8, the monomer unit content in the copolymer was 8% by mass of styrene units, 82% by mass of MMA units, and 10% by mass of glutarimide units, and the glass transition temperature was 128°C.

[0146] (Manufacturing Example 3: Methacrylic Resin C) In a reaction vessel equipped with a stirrer, temperature sensor, cooling tube, nitrogen inlet tube, and dropping pump, 5.40 parts by mass of methyl 2-(hydroxymethyl)acrylate (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 charged, and the temperature was raised to 105°C while passing nitrogen through. Solution polymerization was carried out at 105°C to 110°C while adding a solution consisting of 3.63 parts by mass of toluene and 0.245 parts by mass of t-amyl peroxyisononanoate as an initial initiator dropwise over 9 minutes. Then, 11 minutes later, a solution consisting of 4.42 parts by mass of toluene and 0.298 parts by mass of t-amyl peroxyisononanoate was added dropwise over 180 minutes as a dropping initiator. Furthermore, simultaneously with the addition of the dropwise initiator, a solution consisting of 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 to 110°C, followed by maturation for another 100 minutes. To the obtained polymerization solution, a solution consisting of 1.20 parts by mass of toluene and 0.0750 parts by mass of stearyl phosphate was added as a catalyst for the cyclization condensation reaction (cyclization catalyst), and the cyclization condensation reaction to form a lactone ring structure was carried out under reflux at approximately 90°C to 110°C for 1.5 hours. Next, the obtained polymerization solution was passed through a multi-tube heat exchanger maintained at 220°C to complete the cyclization condensation reaction, and then the polymerization solution was defolarated by introducing it into a vented screw twin-screw extruder (L / D = 52) equipped with a leaf-disc type polymer filter (filtration accuracy 5 μm) at its tip at a processing rate of 90 parts by mass / hour in terms of resin volume. The twin-screw extruder with vents was configured with one rear vent and four fore vents (referred to as the first, second, third, and fourth vents from upstream). The barrel temperature was 220°C, and the pressure was reduced to 13.3–400 hPa (10–300 mmHg). During defoliation, deionized water was added at a rate of 1.3 parts by mass / hour from behind the first, second, and third vents. The obtained methacrylic resin C had a weight-average molecular weight of 102,000, a Mw / Mn ratio of 2.3, a glass transition temperature of 125°C, and the proportions of MMA units, styrene units, lactone ring structures, and RHMA units in the copolymer were 76.8% by mass, 4.6% by mass, 16.9% by mass, and 1.7% by mass, respectively.

[0147] (Production Example 4: Methacrylic Resin D) A monomer composition consisting of 63.08 parts by mass of MMA, 38.54 parts by mass of styrene, and 0.46 parts by mass of t-amyl peroxy-2-ethylhexanoate as a polymerization initiator was continuously supplied at 1 kg / h to a 10 L complete mixing tank equipped with helical ribbon blades, and continuous polymerization was carried out at an average residence time of 2.5 hours and a polymerization temperature of 150°C. The liquid was continuously withdrawn from the bottom of the polymerization tank to maintain a constant liquid level and supplied to a concentration device consisting of a tubular heat exchanger and a vaporization tank for defloration. The vacuum level in the vaporization tank was set to 10 to 15 Torr. The resin flowing down the vaporization tank was discharged with a screw pump, extruded from a strand die, water-cooled and pelletized, and introduced into a solvent removal device to obtain pelletized methyl methacrylate-styrene copolymer. This copolymer was dissolved in methyl isobutyrate to prepare a 10% by mass methyl isobutyrate solution. 500 parts by mass of a 10% by mass methyl isobutyrate solution of this copolymer and 1 part by mass of 10% by mass Pd / C as a hydrogenation catalyst were charged into a 1000 mL autoclave. The mixture was maintained at a hydrogen pressure of 9 MPa and 200°C for 15 hours to hydrogenate the aromatic double bonds of the styrene moiety of the copolymer. The hydrogenation catalyst was removed by filtration, and 0.04 parts by mass of Rikemar H-100 was added to the polymer solution and mixed. The solution was then supplied to a concentration apparatus consisting of a tubular heat exchanger and a vaporization tank for defoliation. The vacuum level in the vaporization tank was set to 10-15 Torr. The resin flowing down the vaporization tank was discharged with a gear pump, extruded from a strand die, water-cooled, and pelletized to obtain methacrylic resin D. When the composition of the obtained pellets was examined, absorbance measurements at a wavelength of 260 nm showed that the hydrogenation rate of the aromatic double bonds of the styrene moiety was 99%. Furthermore, NMR measurements revealed that the structural units derived from the MMA and vinylcyclohexane monomers in the copolymer accounted for 60.7% by mass 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.

[0148] (Production Example 5: Methacrylic Resin E) Methacrylic resin E was obtained in the same manner as in Production Example 4, except that the amount of MMA was 75.09 parts by mass and styrene was 26.04 parts by mass. When the composition of the obtained pellets was examined, absorbance measurement at a wavelength of 260 nm showed that the hydrogenation rate of the aromatic double bond in the styrene moiety was 99%. NMR measurement showed that the structural units derived from the MMA and vinylcyclohexane monomers in the copolymer were 73.2% by mass and 26.8% by mass, respectively. The weight-average molecular weight was 148,000, Mw / Mn was 2.0, and the glass transition temperature was 118°C.

[0149] (Production Example 6: Methacrylic Resin F) In a container equipped with a stirrer fitted with four inclined paddle blades, 2 kg of water, 65 g of tricalcium phosphate, 39 g of calcium carbonate, and 0.39 g of sodium lauryl sulfate were added to obtain mixture (a). Next, 26 kg of water was added to a 60 L reactor equipped with a stirrer fitted with three swept-back blades and the temperature was raised to 75°C. Mixture (a) was added, followed by 22 kg of monomer mixture, which had been pre-mixed with 96.5 parts by mass of MMA, 3.5 parts by mass of methyl acrylate, 0.28 parts by mass of the chain transfer agent n-octyl mercaptan, and 0.25 parts by mass of the polymerization initiator t-butyl peroxy-2-ethylhexanoate. Suspension polymerization was carried out while maintaining a temperature of approximately 80°C, and an exothermic peak was observed approximately 120 minutes after the addition of the raw material mixture. Subsequently, the temperature was raised to 97°C at a rate of 1°C / min, and the mixture was aged for 120 minutes to substantially complete the polymerization reaction. Next, the mixture was cooled to 50°C, and 20% by mass sulfuric acid was added to dissolve the suspension agent. Then, the polymerization reaction solution was sieved through a 1.68 mm mesh to remove aggregates, and the water was filtered off. The resulting slurry was dehydrated to obtain bead-shaped polymers. The obtained bead-shaped polymers were washed with water, dehydrated in the same manner as above, and then washed again with deionized water, repeating the dehydration process to obtain polymer particles. The average particle size was 0.30 mm. The obtained polymer particles were extruded at 200 rpm and 10 kg / hour (in terms of resin volume) using a 3-vent φ37 mm extruder with the cylinder temperature near the die set to 240°C, the kneading section cylinder temperature set to 240°C, and the temperature from resin input to the kneading section set to 220°C, while defoliating. The extruded strands were water-cooled and cut to obtain resin pellets. The weight-average molecular weight of the obtained resin pellets was 100,000. The resin composition determined by NMR was 96.5% by mass of MMA units and 3.5% by mass of methyl acrylate units, and the glass transition temperature was 115°C.

[0150] <Evaluation> The resins produced in the manufacturing examples were evaluated as follows: (1) Analysis of structural units Unless otherwise specified in each manufacturing example, １ H-NMR measurement and １３ The structural units of the manufactured thermoplastic resin were identified and their abundances were calculated using C-NMR measurements. １ H-NMR measurement and１３ The measurement conditions for C-NMR are as follows: • Measurement instrument: JEOL Ltd. ECZ400 • Measurement solvent: CDCl ３ or DMSO-d ６ ・Measurement temperature: 40℃

[0151] (2) Molecular Weight Measurement The weight-average molecular weight (Mw) and number-average molecular weight (Mn) of the thermoplastic resin produced in the manufacturing example were measured using the following apparatus and conditions. ・Measuring apparatus: Gel permeation chromatography (HLC-8320GPC) manufactured by Tosoh Corporation ・Measurement conditions: Columns: One TSKguardcolumn SuperH-H, two TSKgel SuperHM-M, and one TSKgel SuperH2500 were used in series. Column temperature: 40°C Developing solvent: Tetrahydrofuran, flow rate: 0.6 mL / min, 0.1 g / L of 2,6-di-t-butyl-4-methylphenol (BHT) was added as an internal standard. Detector: RI (differential refraction) detector, detection sensitivity: 3.0 mV / min Sample: 20 mL solution of tetrahydrofuran containing 0.02 g of thermoplastic resin. Injection volume: 10 μL Calibration curve standard samples: The following 10 types of polymethyl methacrylate (manufactured by Polymer Laboratories; PMMACalibrication Kit M-M-10) with known monodisperse weight peak molecular weights and different molecular weights were used. Weight 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 against the elution time of the thermoplastic resin was measured. Based on the calibration curve obtained from the measurement of the above-mentioned standard samples for calibration, the weight-average molecular weight (Mw) and number-average molecular weight (Mn) of the thermoplastic resin were determined.

[0152] (3) Measurement of glass transition temperature The glass transition temperature (Tg) (°C) of the thermoplastic resin was measured in accordance with JIS-K7121. First, four pieces (four locations) of approximately 10 mg each were cut from a sample that had been conditioned under standard conditions (23°C, 50% RH) (left at 23°C for one week) to be used as test pieces. Next, a differential scanning calorimeter (Diamond DSC, manufactured by PerkinElmer Japan Co., Ltd.) was used under nitrogen gas flow rate of 25 mL / min. The temperature was raised from room temperature (23°C) to 200°C at 10°C / min (first heating), and held at 200°C for 5 minutes to completely melt the sample. Then, the temperature was lowered from 200°C to 40°C at 10°C / min, held at 40°C for 5 minutes, and then heated again under the same heating conditions (second heating). The intersection point (midpoint glass transition temperature) of the DSC curve drawn during the step-like change portion of the curve during the second heating and a straight line equidistant in the vertical direction from each baseline extension was measured as the glass transition temperature (Tg) (°C). Four measurements were taken per sample, and the arithmetic mean of the four points (rounded to the nearest whole number) was taken as the measured value.

[0153] [Example 1] (Molding of a biconvex lens) 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 injection molded using an injection molding machine (FANUC S-2000i50B). The finished product has an aspherical shape with the first optical effective surface containing the optical axis and a radius of curvature of R93.5 mm on one side, with a cone constant k = -1.12452 and no even-order constants set. The second effective surface containing the optical axis is a spherical shape with 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 for molding. The holding pressure was set to 90 MPa for 5 seconds in the first stage, and then to 70 MPa for 4 seconds in the second holding stage to relieve stress strain inside the molded product. Furthermore, molding was carried out with the injection speed set to 10 mm / s to obtain a biconvex lens molded product. (Deposition of inorganic oxide film) An inorganic oxide film was deposited on the second optically effective surface of the biconvex lens molded product obtained above using a vacuum deposition apparatus (SAPIO SGC-1300, manufactured by Showa Vacuum Co., Ltd.) by resistance heating deposition method. The biconvex lens molded product was placed in the vacuum deposition apparatus, and then a silicon oxide layer with a refractive index of 1.58 and a film thickness of 320 nm was deposited using SiO as the deposition material. During film deposition, oxygen gas was introduced as the reaction gas, and the biconvex lens molded product, which was the target of film deposition, was not heated during the deposition process. Subsequently, an inorganic oxide film was deposited on the first optically effective surface of the biconvex lens molded product. Except that the deposition surface was the first optically effective surface, a silicon oxide layer with a refractive index of 1.58 and a thickness of 320 nm was deposited by resistance heating deposition in the same manner as the deposition of the second optically effective surface, thereby obtaining a biconvex lens in which silicon oxide layers were deposited on both the first and second optically effective surfaces. (Deposition of optical thin film) An optical thin film was deposited on the biconvex lens in which silicon oxide layers were deposited on both the first and second optically effective surfaces by vacuum deposition. An electron gun without a backscattered electron trap was used for deposition. First, TiO was deposited on the first optically effective surface. ２ and SiO ２ An anti-reflective film consisting of a laminated structure was formed. Following the formation of the silicon oxide layer on the first optically effective surface as described above, Ti was used as the deposition material. ３ O ５Using this method, the biconvex lens molded product, which is the target of the film deposition, is not specifically heated, and a TiO2 film with a refractive index of 2.12 and a film thickness of 25 nm is deposited by electron beam heating. ２ The film was formed using SiO as the deposition material. ２ Using this method, the biconvex lens molded product, which is the target of the film deposition, is heated by electron beam heating to deposit a film of SiO2 with a refractive index of 1.46 and a film thickness of 24 nm. ２ A film was formed. Furthermore, these operations were repeated to create a TiO film with a refractive index of 2.42 and a film thickness of 57 nm. ２ SiO2 with a refractive index of 1.46 and a film thickness of 9 nm ２ TiO2 with a refractive index of 2.42 and a film thickness of 35 nm ２ SiO2 with a refractive index of 1.46 and a film thickness of 90 nm ２ A film was formed. Through the above procedure, an anti-reflective film with a total film thickness of 240 nm was formed. Subsequently, TiO was applied to the second optically effective surface. ２ and SiO ２ A partially permeable film consisting of a layered structure was formed. Ti was used as the deposition material. ３ O ５ Using this method, the biconvex lens molded product, which is the target of the film deposition, is coated with TiO2 with a refractive index of 2.12 and a film thickness of 30 nm without any special heating. ２ The film was formed using SiO as the deposition material. ２ Using this method, the biconvex lens molded product, which is the target of the film deposition, is coated with SiO2 with a refractive index of 1.46 and a film thickness of 25 nm without any special heating. ２ A film was formed. Furthermore, these operations were repeated to create a TiO film with a refractive index of 2.42 and a film thickness of 56 nm. ２ SiO2 with a refractive index of 1.46 and a film thickness of 97 nm ２ TiO2 with a refractive index of 2.42 and a film thickness of 50 nm ２ SiO2 with a refractive index of 1.46 and a film thickness of 38 nm ２ A film was deposited, resulting in a partially permeable film with a total thickness of 296 nm.

[0154] [Example 2] (Molding of Plano-Convex Lens) Using the methacrylic resin A obtained in Manufacturing Example 1, a plano-convex lens with an optical axis thickness of 3.2 mm and an effective diameter of φ41 mm was injection molded using an injection molding machine (FANUC S-2000i50B). The finished product has an aspherical shape with the first optical effective surface containing the optical axis and a radius of curvature of the convex surface of R93.5 mm, with a cone constant k = -1.12452 and no even-order constants set. The second optical effective surface is a planar shape with R∞ and contains the optical axis. 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 for molding. The holding pressure was set to 100 MPa for 5 seconds in the first stage, and then to 80 MPa for 4 seconds in the second holding stage to relieve stress strain inside the molded product. Furthermore, molding was performed with the injection speed set to 10 mm / s to obtain a plano-convex lens. (Deposition of inorganic oxide film) A plano-convex lens was obtained in the same manner as in Example 1, except that the refractive index of the silicon oxide layer deposited on the first optical effective surface was set to 1.49 and the film thickness to 370 nm, and the refractive index of the silicon oxide layer deposited on the second optical effective surface was set to 1.49. (Deposition of optical thin film) For the plano-convex lens in which silicon oxide layers were deposited on both the first and second optical effective surfaces, an optical thin film was deposited only on the first optical effective surface by vacuum deposition. An electron gun without a backscattered electron trap was used for deposition. TiO ２ and SiO ２ A partially permeable film consisting of a laminated structure was formed. Following the formation of the silicon oxide layer on the first optically effective surface described above, Ti was used as the deposition material. ３ O ５ Using this method, the biconvex lens molded product, which is the target of the film deposition, is not specifically heated, and a TiO2 film with a refractive index of 2.12 and a film thickness of 16.2 nm is deposited by electron beam heating. ２ The film was formed using SiO as the deposition material. ２ Using this method, the biconvex lens molded product was subjected to film deposition without special heating, and an electron beam heating method was used to deposit SiO2 with a refractive index of 1.46 and a film thickness of 28.6 nm. ２ A film was formed. Furthermore, these operations were repeated to create a TiO film with a refractive index of 2.42 and a film thickness of 108.0 nm.２ SiO2 with a refractive index of 1.46 and a film thickness of 165.2 nm ２ TiO2 with a refractive index of 2.42 and a film thickness of 67.7 nm ２ SiO2 with a refractive index of 1.46 and a thickness of 109.6 nm ２ TiO2 with a refractive index of 2.42 and a film thickness of 31.3 nm ２ A film was deposited, resulting in a partially transparent film with a total thickness of 526.5 nm.

[0155] [Example 3] (Molding of Right-Angle Prism) Using the methacrylic resin A obtained in Manufacturing Example 1, a right-angle prism was injection molded using an injection molding machine (FANUC, α-S50iA) with a triangular prism mold having a base of a right triangle with sides of 12 mm and a height of 15 mm. A gate for injecting resin into the cavity was provided on the base of the triangular prism. Viewed from the base with the gate, the side of the triangular prism containing the hypotenuse of the right triangle was designated as the first optically effective surface, the side touching the first optically effective surface in a clockwise direction was designated as the second optically effective surface, and the side touching the second optically effective surface in a clockwise direction was designated as the third optically effective surface. 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, and molding was performed. The holding pressure was set to 95 MPa for 6 seconds in the first stage, and then to 60 MPa for 3 seconds in the second holding stage to relieve stress strain inside the molded product. The injection speed was set to 6 mm / s to perform molding and obtain a right-angle prism molded product. (Deposition of inorganic oxide film) Before deposition on the second optical effective surface, a silicon oxide layer was deposited on the third optical effective surface. The silicon oxide layer had a refractive index of 1.55 and a film thickness of 320 nm, and the silicon oxide layer was deposited by resistance heating deposition in the same manner as the deposition on the second optical effective surface in Example 1. Similarly, deposition was performed on the second optical effective surface and the first optical effective surface, and a right-angle prism was obtained in which silicon oxide layers were deposited on all three optical effective surfaces: the first optical effective surface, the second optical effective surface, and the third optical effective surface. (Deposition of optical thin films) Optical thin films were deposited on a right-angle prism, which had silicon oxide layers deposited on all three optical effective surfaces: the first, second, and third optical effective surfaces, using vacuum deposition. An electron gun without a backscattered electron trap was used for deposition. First, TiO ２ and SiO２ An anti-reflective coating consisting of a laminated structure was deposited. Following the deposition of the silicon oxide layer on the first optical surface as described above, an anti-reflective coating with a total thickness of 240 nm was deposited in the same manner as in Example 1. The same deposition was performed on the second and third optical surfaces in the same order to obtain a right-angle prism in which the anti-reflective coating was deposited on all optical surfaces.

[0156] [Example 4] (Molding of a biconvex lens) A biconvex lens molded product was obtained using the methacrylic resin B obtained in Manufacturing Example 2, and otherwise in the same manner as in Example 1. (Deposition of inorganic oxide film) A silicon oxide layer was deposited in this order on the second optical effective surface and the first optical effective surface of the biconvex lens molded product obtained above. A biconvex lens was obtained in which a silicon oxide layer was deposited on both the first and second optical effective surfaces, with a refractive index of 1.58 and a film thickness of 390 nm, and otherwise in the same manner as in Example 1. (Deposition of optical thin film) An optical thin film was deposited on the biconvex lens in which a silicon oxide layer was deposited on both the first and second optical effective surfaces, in the same manner as in Example 1.

[0157] [Example 5] In Example 4, the methacrylic resin C obtained in Manufacturing Example 3 was used when molding the biconvex lens, and otherwise the procedure was the same as in Example 4 to obtain a biconvex lens.

[0158] [Example 6] In Example 4, the methacrylic resin D obtained in Manufacturing Example 4 was used when molding the biconvex lens, and otherwise the procedure was the same as in Example 4 to obtain a biconvex lens.

[0159] [Example 7] In Example 4, the methacrylic resin E obtained in Manufacturing Example 5 was used when molding the biconvex lens, and otherwise the procedure was the same as in Example 4 to obtain a biconvex lens.

[0160] [Example 8] In Example 4, the methacrylic resin F obtained in Manufacturing Example 6 was used when molding the biconvex lens, and otherwise the procedure was the same as in Example 4 to obtain a biconvex lens.

[0161] [Example 9] (Forming of a flat plate) Acrylite L (manufactured by Mitsubishi Chemical Corporation) was used as the methacrylic resin G. A 3 mm thick plate of methacrylic resin G was cut using a circular saw to create a 60 mm square flat plate. (Deposition of inorganic oxide film) The pair of surfaces with the largest area of ​​the flat plate obtained above were designated as the optically effective surfaces, and silicon oxide films were deposited on the second optically effective surface and the first optically effective surface in that order. The surface on which the film was deposited first was designated as the second optically effective surface. The refractive index was set to 1.58 and the film thickness to 390 nm, and otherwise the procedure was the same as in Example 1 to obtain a flat plate on which silicon oxide layers were deposited on both the first and second optically effective surfaces. (Deposition of optical thin film) An optical thin film was deposited on the flat plate on which silicon oxide layers were deposited on both the first and second optically effective surfaces in the same manner as in Example 1.

[0162] [Comparative Example 1] A biconvex lens was obtained in the same conditions as in Example 1, except that the deposition order of the inorganic oxide film and the optical thin film was changed. The specific deposition order is as follows: First, a silicon oxide layer with a thickness of 320 nm was deposited on the first optical effective surface by resistance heating deposition, and then an anti-reflective film with a total thickness of 240 nm was deposited. Subsequently, a silicon oxide layer with a thickness of 320 nm was deposited on the second optical effective surface by resistance heating deposition, and then a partially transparent film with a total thickness of 296 nm was deposited.

[0163] [Comparative Example 2] A biconvex lens was obtained in the same conditions as in Example 1, except that the film thickness of the inorganic oxide was changed. Specifically, a silicon oxide layer with a film thickness of 120 nm was deposited on both the first and second optical effective surfaces by resistance heating deposition.

[0164] [Comparative Example 3] In Example 1, inorganic oxide film deposition was omitted, and an electron gun equipped with a backscattered electron trap was used for optical thin film deposition. Otherwise, a biconvex lens was obtained in the same manner as in Example 1. [Comparative Example 4] In Example 1, inorganic oxide film deposition was omitted, and a hard coat was deposited by dip coating before deposition of the optical thin film. The biconvex lens molded product was immersed in a coating solution (Artiens RioDuras LC1587-55), coated at a pulling speed of 1 mm / s, dried in an 80°C oven for 60 seconds, and each surface of the biconvex lens molded product was exposed to an integrated light intensity of 400 mJ / cm using an 80 W / cm high-pressure mercury lamp. ２ The material was cured by irradiation with UV light. Otherwise, a biconvex lens was obtained in the same manner as in Example 1.

[0165] <Evaluation> The resin optical elements prepared in each of the above examples and comparative examples were evaluated as follows. The evaluation results are shown in Table 1.

[0166] (1) X-ray photoelectron spectroscopy analysis Narrow scan spectra were measured for each layered structure of the resin optical element by X-ray photoelectron spectroscopy, focusing on the electronic state of the 1s orbital of carbon atoms in the surface layer of the resin substrate and in the resin substrate. The measurement conditions were as follows: ・Equipment used: ULVAC-PHI VersaProbe II ・Excitation source: Monochromatic Al Kα 15kV × 3.3mA ・Analysis size: Approximately 200 μmφ ・Photoelectron extraction angle: 45 degrees ・Pass energy: 117.4 eV (Survey), 46.95 eV (Narrow) ・Charge correction: C1s = 284.6 eV The normalized intensity of the peak originating from the C=O bond was measured at the surface layer of the resin part and at a depth of 5 μm from the surface layer of the resin part, and the I ｓｕｒｆ / I ｉｎｔ We calculated I. ｓｕｒｆ The aforementioned method (I) was used as the sample pretreatment method for measuring the value.

[0167] (2) Adhesion Test Cross-cuts were made on each optically effective surface of the resin optical element using an art knife to create 25 1 mm x 1 mm grids. Cellophane tape (Nichiban LP-24) was applied to the grids, and the tape was peeled off in one swift motion in the direction of a peeling angle of 120 degrees. This operation was performed a total of 10 times, using a new tape each time (tape that had been used once was not reused). After this, the surface condition of the cross-cut areas was observed to see if peeling of the inorganic oxide film had occurred. The results were classified as follows, with classification 0 or 1 being A (good), classification 2 being B (usable), and classifications 3 to 5 being C (poor). The test was conducted in a constant temperature and humidity environment of 23°C and 50% RH. The peeling angle was defined as 180 degrees when the end of the tape was held and folded back so that the back of the tape overlapped. (Classification) 0: The edges of the cuts are perfectly smooth, and there is no peeling in any of the grids. 1: There is slight peeling of the film at the intersection of the cuts. 1: The percentage of peeling at the cross-cut area does not clearly exceed 5% of the total area of ​​the cross-cut section, which is 100% of the total area of ​​the cross-cut section. 2: There is small peeling along the edges of the cuts and / or at the intersections. The percentage of peeling at the cross-cut area clearly exceeds 5% but does not exceed 15% of the total area of ​​the cross-cut section, which is 100% of the total area of ​​the cross-cut section. 3: There is partial or complete peeling along the edges of the cuts and / or partial or complete peeling in several grids. The percentage of peeling at the cross-cut area clearly exceeds 15% but does not exceed 35% of the total area of ​​the cross-cut section, which is 100% of the total area of ​​the cross-cut section. 4: There is partial or complete large peeling along the edges of the cuts and / or complete large peeling in several grids. The percentage of peeling at the cross-cut area clearly exceeds 35% but does not exceed 65% of the total area of ​​the cross-cut section, which is 100% of the total area of ​​the cross-cut section. 5: Any of the following types of peeling that cannot be classified as Category 4.

[0168] (3) High Temperature and High Humidity Test The resin optical elements prepared in the examples and comparative examples were subjected to reliability tests under the following temperature and humidity conditions to evaluate their reliability in a high temperature and high humidity environment. The optical elements were placed in a constant temperature and humidity chamber (ESPEC PL-2J) set to the specified temperature and humidity conditions, held for 200 hours, and then removed and evaluated in (3-1) to (3-2). Temperature and humidity conditions: 85°C, 85%RH

[0169] (3-1) Adhesion Test Cross-cuts were made on each optically effective surface of the resin optical element using an art knife to create 25 1 mm x 1 mm grids. Cellophane tape (Nichiban LP-24) was applied to the grids, and the tape was peeled off in one swift motion in the direction of a 120-degree peeling angle. This operation was performed a total of 10 times, using a new tape each time (not using tape that had been used once). After this, the surface condition of the cross-cut areas was observed to see if peeling of the inorganic oxide film had occurred. The results were classified as follows, with classification 0 or 1 being A (good), classification 2 being B (usable), and classifications 3 to 5 being C (poor). The test was conducted in a constant temperature and humidity environment of 23°C and 50% RH. The peeling angle was defined as 180 degrees when the end of the tape was held and folded back so that the back of the tape overlapped. (Classification) 0: The edges of the cuts are perfectly smooth, and there is no peeling in any of the grids. 1: There is slight peeling of the film at the intersection of the cuts. 1: The percentage of peeling at the cross-cut area does not clearly exceed 5% of the total area of ​​the cross-cut section, which is 100% of the total area of ​​the cross-cut section. 2: There is small peeling along the edges of the cuts and / or at the intersections. The percentage of peeling at the cross-cut area clearly exceeds 5% but does not exceed 15% of the total area of ​​the cross-cut section, which is 100% of the total area of ​​the cross-cut section. 3: There is partial or complete peeling along the edges of the cuts and / or partial or complete peeling in several grids. The percentage of peeling at the cross-cut area clearly exceeds 15% but does not exceed 35% of the total area of ​​the cross-cut section, which is 100% of the total area of ​​the cross-cut section. 4: There is partial or complete large peeling along the edges of the cuts and / or complete large peeling in several grids. The percentage of peeling at the cross-cut area clearly exceeds 35% but does not exceed 65% of the total area of ​​the cross-cut section, which is 100% of the total area of ​​the cross-cut section. 5: Any of the following types of peeling that cannot be classified as Category 4.

[0170] (3-2) Visual Evaluation Before (i.e., 0 hours) and after the specified time of the reliability test in a high temperature and high humidity environment, the appearance of each optically effective surface of the resin optical element that did not deform was visually observed to check for the presence or absence of cracks in the inorganic oxide film. The evaluation was performed according to the following criteria: A (Good): No cracks were observed. B (Fairly Good): A few cracks (about 1 to 2) were observed. C (Fairly Poor): Numerous cracks (about several to several dozen) were observed. D (Poor): Countless cracks were observed.

[0171] (3-3) Evaluation of Shape Retention Non-contact shape accuracy measurements were performed on biconvex lens molded products and resin optical elements made using said molded products under the following conditions. The shape accuracy measurements were performed on the surface on which the partially transparent film was deposited. This was because sufficient reflected light intensity could not be obtained on the surface on which the anti-reflective film was deposited, making measurement using this method difficult. Equipment used: NH-3SPs manufactured by Mitaka Kohki Measurement surface: Side of the partially transparent film deposition Measurement location: Passing through the optical center of the optical element in a direction perpendicular to the flow Thereafter, the obtained shape accuracy measurement results were standardized according to the following criteria. A (Good): Absolute value of ΔPV is less than 2.0 μm B (Fairly Good): Absolute value of ΔPV is 2.0 μm or more and less than 5.0 μm C (Poor): Absolute value of ΔPV is 5.0 μm or more Here, ΔPV is the change in PV in the resin optical element (after film formation) with respect to the biconvex lens molded product (before film formation), and the Best Fit R value of the biconvex lens molded product (before film formation) was used in common for the calculation.

[0172] [Supplement based on Rule 26, 13.05.2026]

[0173] [Example 10] (Molding of a biconvex lens) 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 injection molded using an injection molding machine (FANUC S-2000i50B). As a finished product, one side is an aspherical shape with a radius of curvature of R93.5 mm, which includes the optical axis, and the cone constant k = -1.12452, with no even-order constants set. The other side is a spherical shape with a radius of R67 mm, which includes the optical axis. 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 for molding. The holding pressure was set to 90 MPa for 5 seconds in the first stage, and then to 70 MPa for 4 seconds in the second holding stage to relieve stress strain inside the molded product. Furthermore, the injection speed was set to 10 mm / s to perform the molding process, and a biconvex lens molded product was obtained.

[0174] (Deposition of the underlayer) An underlayer was deposited on the spherical side of the biconvex lens molded product obtained above using a vacuum deposition apparatus (SAPIO SGC-1300, manufactured by Showa Vacuum Co., Ltd.) by resistance heating deposition. The biconvex lens molded product was placed in the vacuum deposition apparatus, and a silicon oxide layer with a refractive index of 1.58 and a thickness of 320 nm was deposited using SiO as the deposition material. During deposition, oxygen gas was introduced as the reaction gas, and the biconvex lens molded product, which was the target of the deposition, was not heated during the deposition process. Next, an underlayer was deposited on the aspherical side of the biconvex lens molded product. Except that the deposition surface was the aspherical side, an underlayer was deposited on the aspherical side using resistance heating deposition in the same manner as the deposition on the spherical side, and a silicon oxide layer with a refractive index of 1.58 and a thickness of 320 nm was deposited, obtaining a biconvex lens with silicon oxide layers deposited on both the spherical and aspherical sides.

[0175] (Anti-reflective coating deposition) An anti-reflective coating was deposited on the aspherical side of a biconvex lens, which had silicon oxide layers deposited on both the spherical and aspherical sides, using vacuum deposition. An electron gun without a backscattered electron trap was used for deposition.

[0176] Following the aforementioned deposition of the silicon oxide layer on the aspherical side, Ti is used as the deposition material. ３ O ５Using this method, the biconvex lens molded product to be coated is not specifically heated, and a TiO2 film with a refractive index of 2.12 and a film thickness of 25 nm is deposited by electron beam heating. ２ The film was deposited.

[0177] Next, as a deposition material, SiO ２ Using this method, the biconvex lens molded product, which is the target of the film deposition, is not heated in particular, and a film of SiO2 with a refractive index of 1.46 and a film thickness of 24 nm is deposited by electron beam heating. ２ A thin film was formed.

[0178] Furthermore, by repeating these operations, a TiO2 film with a refractive index of 2.42 and a film thickness of 57 nm is obtained. ２ SiO2 with a refractive index of 1.46 and a film thickness of 9 nm ２ TiO2 with a refractive index of 2.42 and a film thickness of 35 nm ２ SiO2 with a refractive index of 1.46 and a film thickness of 90 nm ２ A film was deposited. Through the above procedure, an anti-reflective film with a total film thickness of 240 nm was deposited.

[0179] (Deposition of a partial reflective film) Then, TiO ２ and SiO ２ A partially reflective film consisting of a layered structure was formed. Ti was used as the deposition material. ３ O ５ Using this method, the biconvex lens molded product, which is the target of the film deposition, is coated with TiO2 with a refractive index of 2.12 and a film thickness of 30 nm without any special heating. ２ The film was formed using SiO as the deposition material. ２ Using this method, the biconvex lens molded product, which is the target of the film deposition, is coated with SiO2 with a refractive index of 1.45 and a film thickness of 25 nm without any special heating. ２ A film was formed. Furthermore, these operations were repeated to create a TiO film with a refractive index of 2.42 and a film thickness of 56 nm. ２ SiO2 with a refractive index of 1.46 and a film thickness of 97 nm ２ TiO2 with a refractive index of 2.42 and a film thickness of 50 nm ２ SiO2 with a refractive index of 1.46 and a film thickness of 38 nm ２ A film was deposited, resulting in a partial reflective film with a total film thickness of 296 nm.

[0180] [Example 11] (Molding of Plano-Convex Lens) Using the methacrylic resin A obtained in Manufacturing Example 1, a plano-convex lens with an optical axis thickness of 3.2 mm and an effective diameter of φ41 mm was injection molded using an injection molding machine (FANUC S-2000i50B). The finished product has an aspherical shape with the first optical effective surface containing the optical axis and a radius of curvature of the convex surface of R93.5 mm, with a cone constant k = -1.12452 and no even-order constants set. The second optical effective surface is a planar shape with R∞ and contains the optical axis. 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 for molding. The holding pressure was set to 100 MPa for 5 seconds in the first stage, and then to 80 MPa for 4 seconds in the second holding stage to relieve stress strain inside the molded product. Furthermore, molding was carried out with the injection speed set to 10 mm / s to obtain a plano-convex lens molded product. (Inorganic oxide film / underlayer deposition) An inorganic oxide film was deposited on the second optically effective surface of the plano-convex lens molded product obtained above using a vacuum deposition apparatus (SAPIO SGC-1300, manufactured by Showa Vacuum Co., Ltd.) by resistance heating deposition method. The plano-convex lens molded product was placed inside the vacuum deposition apparatus, and the vacuum chamber was set to 1.5 × 10 －３ The system was evacuated to Pa. Next, SiO tablets filled in a molybdenum boat were heated and sublimated by resistance heating to deposit a silicon oxide layer with a refractive index of 1.58 and a film thickness of 390 nm. During film deposition, oxygen gas was introduced as the reaction gas, and the plano-convex lens molded product, which was the target of the film deposition, was not heated during the deposition process. Subsequently, an inorganic oxide film, which was the underlayer, was deposited on the first optical effective surface of the plano-convex lens molded product. The deposition surface was designated as the first optical effective surface, and the silicon oxide layer was deposited by resistance heating deposition so that the resulting film had a refractive index of 1.49 and a film thickness of 390 nm, with the rest of the process being the same as for the deposition of the second optical effective surface. This resulted in a plano-convex lens with silicon oxide layers deposited on both the first and second optical effective surfaces. (Deposition of partial reflective film) A partial reflective film was deposited on the first optical effective surface of the plano-convex lens, which had silicon oxide layers deposited on both the first and second optical effective surfaces, using the same method as in Example 10. (Formation of anti-reflective coating) Subsequently, an anti-reflective coating was formed on the second optically effective surface using the same method as in Example 10.

[0181] [Example 12] In Example 10, the film thickness of the underlayer constituting the anti-reflective coating of the second optical effective surface was changed, and the film formation conditions and film thickness of the multilayer constituting the underlayer constituting the partial reflective coating of the first optical effective surface were changed. Otherwise, a biconvex lens was obtained in the same manner as in Example 10. Specifically, the film thickness of the underlayer of the second optical effective surface was set to 390 nm, and the underlayer of the first optical effective surface had a refractive index of 1.55 and a film thickness of 330 nm. Furthermore, the multilayer structure of the first optical effective surface consisted of TiO2 with a refractive index of 2.12 and a film thickness of 19 nm, in order from the layer closest to the underlayer. ２ SiO2 with a refractive index of 1.46 and a film thickness of 31 nm ２ TiO2 with a refractive index of 2.42 and a film thickness of 116 nm ２ SiO2 with a refractive index of 1.46 and a film thickness of 40 nm ２ TiO2 with a refractive index of 2.42 and a film thickness of 70 nm ２ A partial reflective film with a total film thickness of 275 nm was then deposited.

[0182] [Example 13] A biconvex lens was obtained in the same manner as in Example 12, except that the thickness of the underlayer and the thickness of the multilayer film constituting the partial reflective film of the first optical effective surface were changed. Specifically, the thickness of the underlayer of the first optical effective surface was set to 380 nm. The multilayer film of the first optical effective surface was composed of TiO2 with a refractive index of 2.12 and a thickness of 20 nm, in order from the layer closest to the underlayer. ２ SiO2 with a refractive index of 1.46 and a film thickness of 28 nm ２ TiO2 with a refractive index of 2.42 and a film thickness of 111 nm ２ SiO2 with a refractive index of 1.46 and a film thickness of 135 nm ２ TiO2 with a refractive index of 2.42 and a film thickness of 34 nm ２ A partial reflective film with a total film thickness of 327 nm was then deposited.

[0183] [Example 14] A biconvex lens was obtained in the same manner as in Example 10, except that methacrylic resin B was used instead of methacrylic resin A, and the film thickness of the underlayer of the first optical effective surface and the second optical effective surface was set to 390 nm.

[0184] [Example 15] A biconvex lens was obtained in the same manner as in Example 14, except that methacrylic resin C was used instead of methacrylic resin B.

[0185] [Example 16] A biconvex lens was obtained in the same manner as in Example 14, except that methacrylic resin D was used instead of methacrylic resin B.

[0186] [Example 17] A biconvex lens was obtained in the same manner as in Example 14, except that methacrylic resin E was used instead of methacrylic resin B.

[0187] [Example 18] A biconvex lens was obtained in the same manner as in Example 14, except that methacrylic resin F was used instead of methacrylic resin B.

[0188] [Example 19] (Forming of a flat plate) Acrylite L (manufactured by Mitsubishi Chemical Corporation) was used as the methacrylic resin G. A 3 mm thick plate of methacrylic resin G was cut using a circular saw to create a 60 mm square flat plate. (Deposition of the base layer) The pair of surfaces with the largest area of ​​the flat plate obtained above were designated as the optically effective surfaces, and silicon oxide films were deposited on the second optically effective surface and the first optically effective surface in that order. The surface to which the film was deposited first was designated as the second optically effective surface. The refractive index was set to 1.58 and the film thickness to 390 nm, and otherwise the procedure was the same as in Example 1 to obtain a flat plate with silicon oxide layers deposited on both the first and second optically effective surfaces. (Deposition of an optical thin film) An optical thin film was deposited on the flat plate with silicon oxide layers deposited on both the first and second optically effective surfaces in the same manner as in Example 2.

[0189] [Comparative Example 5] A biconvex lens was obtained in the same manner as in Example 4, except that the film thickness of the underlayer of the second optically effective surface was changed. Specifically, the film thickness of the underlayer of the second optically effective surface was set to 120 nm.

[0190] [Comparative Example 6] (Molding of a biconvex lens) A biconvex lens molded product made of methacrylic resin A was obtained in the same manner as in Example 10. (Deposition of underlayer and partial reflective film) An underlayer and a partial reflective film consisting of a multilayer film were deposited on the spherical side of the biconvex lens molded product obtained above using a vacuum deposition apparatus (SAPIO SGC-1300, manufactured by Showa Vacuum Co., Ltd.). The biconvex lens molded product was placed in the vacuum deposition apparatus, and a silicon oxide layer with a refractive index of 1.58 and a film thickness of 380 nm was deposited using resistance heating deposition with SiO as the deposition material. During film deposition, oxygen gas was introduced as the reaction gas, and the biconvex lens molded product to be deposited was not particularly heated during film deposition. Following the deposition of the underlayer, TiO was deposited on the spherical side. ２ and SiO ２ A partially reflective film consisting of a layered structure was deposited by vacuum deposition. Ti was used as the deposition material. ３ O ５ Using this method, the biconvex lens molded product, which is the target of the film deposition, is coated with TiO2 with a refractive index of 2.12 and a film thickness of 16 nm without any special heating. ２ The film was formed using SiO as the deposition material. ２ Using this method, the biconvex lens molded product, which is the target of the film deposition, is coated with SiO2 with a refractive index of 1.46 and a film thickness of 29 nm without any special heating. ２ A film was formed. Furthermore, these operations were repeated to create a TiO film with a refractive index of 2.42 and a film thickness of 108 nm. ２ SiO2 with a refractive index of 1.46 and a film thickness of 165 nm ２ TiO2 with a refractive index of 2.42 and a film thickness of 68 nm ２ SiO2 with a refractive index of 1.46 and a film thickness of 110 nm ２ TiO2 with a refractive index of 2.42 and a film thickness of 31 nm ２A partial reflective film with a total thickness of 527 nm was deposited. An electron gun without a backscattered electron trap was used for deposition. (Deposition of underlayer and anti-reflective film) Next, an anti-reflective film consisting of an underlayer and a multilayer film was deposited on the aspherical side of the biconvex lens molded product. The biconvex lens molded product was placed in a vacuum deposition apparatus, and a silicon oxide layer with a refractive index of 1.52 and a thickness of 340 nm was deposited using resistance heating deposition with SiO as the deposition material. During deposition, oxygen gas was introduced as the reaction gas, and the biconvex lens molded product, which was the target of the deposition, was not heated during deposition. Following the deposition of the underlayer, TiO was deposited on the aspherical side. ２ and SiO ２ An anti-reflective film consisting of a layered structure was deposited by vacuum deposition. Ti was used as the deposition material. ３ O ５ Using this method, the biconvex lens molded product, which is the target of the film deposition, is coated with TiO2 with a refractive index of 2.12 and a film thickness of 25 nm without any special heating. ２ The film was formed using SiO as the deposition material. ２ Using this method, the biconvex lens molded product, which is the target of the film deposition, is coated with SiO2 with a refractive index of 1.46 and a film thickness of 24 nm without any special heating. ２ A film was formed. Furthermore, these operations were repeated to create a TiO film with a refractive index of 2.42 and a film thickness of 57 nm. ２ SiO2 with a refractive index of 1.46 and a film thickness of 9 nm ２ TiO2 with a refractive index of 2.42 and a film thickness of 35 nm ２ SiO2 with a refractive index of 1.46 and a film thickness of 90 nm ２ A film was deposited, resulting in an anti-reflective coating with a total thickness of 240 nm. An electron gun without a backscattered electron trap was used for film deposition.

[0191] [Comparative Example 7] A biconvex lens was obtained in the same manner as in Comparative Example 6, except that all layers of the multilayer film constituting the partial reflective film of the first optically effective surface were formed by ion-assisted deposition.

[0192] <Evaluation> The resin optical elements prepared in each of the above examples and comparative examples were evaluated as follows. The evaluation results are shown in Table 2.

[0193] (4) Spectroscopic reflectance measurement Spectroscopic reflectance measurements were performed on the partially reflective film-deposited surface of resin optical elements using a microscopic spectroscopic reflectance microscope (LambdaVision, LVmicro-RUR) in the wavelength range of 450 nm to 650 nm. In the case of lenses, the measurement point was the intersection of the partially reflective film-deposited surface and the optical axis, and in the case of flat plates, it was the center of the surface. An objective lens with a numerical aperture (NA) of 0.4 was used. Spectroscopic reflectance values ​​were acquired at 1 nm intervals of wavelength, and the average value of the spectral reflectance in the wavelength range of 450 nm to 650 nm was R Ａｖｅ , the maximum value is R Ｍａｘ , the minimum value is R Ｍｉｎ This was done. Also, from the obtained values ​​(R Ｍａｘ -R Ｍｉｎ ) The value of was calculated. (5) X-ray photoelectron spectroscopy analysis For each layered structure of the resin optical element, narrow scan spectra were measured by X-ray photoelectron spectroscopy focusing on the electron state of the 1s orbital of carbon atoms in the surface layer of the resin substrate and in the resin substrate. The measurement conditions were as follows: ・Equipment used: VersaProbe II manufactured by ULVAC-PHI ・Excitation source: Monochromatic Al Kα 15kV × 3.3mA ・Analysis size: Approximately 200 μmφ ・Photoelectron extraction angle: 45 degrees ・Pass energy: 117.4 eV (Survey), 46.95 eV (Narrow) ・Charge correction: C1s = 284.6 eV The normalized strength of the C=O bond in the resin surface layer on the film deposition surface of the partial reflective film, which is the first optically effective surface, was set to I ＨＭ The normalized strength of the C=O bond in the resin surface layer at the nth optically effective surface is I ｎ , toshi, I ｎ / I ＨＭ The values ​​were calculated. The sample pretreatment method was the method described above (I). The measured values ​​were taken from the tape-side peel surface. The normalized intensity of the C=O bond-derived peak was measured at the surface of the resin part and at a depth of 5 μm from the surface of the resin part, and the I values ​​were calculated for both the tape-side peel surface and the substrate-side peel surface. ｓｕｒｆ / I ｉｎｔ We calculated I. ｓｕｒｆ The aforementioned method (I) was used as the sample pretreatment method for measuring the value.

[0194] (6) Adhesion Test Cross-cuts were made on each optically effective surface of the resin optical element using an art knife to create 25 1 mm x 1 mm grids. Cellophane tape (Nichiban LP-24) was applied to the grids, and the tape was peeled off in one swift motion in the direction of a 120-degree peeling angle. This operation was performed a total of 10 times, using a new tape each time (tape that had been used once was not reused). After this, the surface condition of the cross-cut areas was observed to see if peeling of the partial reflective film or optical functional layer had occurred. The results were classified as follows, with classification 0 or 1 being A (good), classification 2 being B (usable), and classifications 3 to 5 being C (poor). The tests were conducted in a constant temperature and humidity environment of 23°C and 50% RH. The peeling angle was defined as 180 degrees when the end of the tape was held and folded back so that the back of the tape overlapped. (Classification) 0: The edges of the cuts are perfectly smooth, and there is no peeling in any of the grids. 1: There is slight peeling of the film at the intersection of the cuts. 1: The percentage of peeling at the cross-cut area does not clearly exceed 5% of the total area of ​​the cross-cut section, which is 100% of the total area of ​​the cross-cut section. 2: There is small peeling along the edges of the cuts and / or at the intersections. The percentage of peeling at the cross-cut area clearly exceeds 5% but does not exceed 15% of the total area of ​​the cross-cut section, which is 100% of the total area of ​​the cross-cut section. 3: There is partial or complete peeling along the edges of the cuts and / or partial or complete peeling in several grids. The percentage of peeling at the cross-cut area clearly exceeds 15% but does not exceed 35% of the total area of ​​the cross-cut section, which is 100% of the total area of ​​the cross-cut section. 4: There is partial or complete large peeling along the edges of the cuts and / or complete large peeling in several grids. The percentage of peeling at the cross-cut area clearly exceeds 35% but does not exceed 65% of the total area of ​​the cross-cut section, which is 100% of the total area of ​​the cross-cut section. 5: Any of the following types of peeling that cannot be classified as Category 4.

[0195] (7) High Temperature and High Humidity Test The resin optical elements prepared in the examples and comparative examples were subjected to reliability tests under the following temperature and humidity conditions to evaluate their reliability in a high temperature and high humidity environment. The optical elements were placed in a constant temperature and humidity chamber (ESPEC PL-2J) set to the specified temperature and humidity conditions, held for 200 hours, and then removed and evaluated according to (4-1) to (4-2). Temperature and humidity condition a: 65°C, 90%RH Temperature and humidity condition b: 85°C, 85%RH

[0196] (7-1) Adhesion Test Cross-cuts were made on each optically effective surface of the resin optical element using an art knife to create 25 1 mm x 1 mm grids. Cellophane tape (Nichiban LP-24) was applied to the grids, and the tape was peeled off in one swift motion in the direction of a 120-degree peeling angle. This operation was performed a total of 10 times, using a new tape each time (tape that had been used once was not reused). After this, the surface condition of the cross-cut areas was observed to see if peeling of the partial reflective film or optical functional layer had occurred. The results were classified as follows, with classification 0 or 1 being A (good), classification 2 being B (usable), and classifications 3 to 5 being C (poor). The test was conducted in a constant temperature and humidity environment of 23°C and 50% RH. The peeling angle was defined as 180 degrees when the end of the tape was held and folded back so that the back of the tape overlapped. (Classification) 0: The edges of the cuts are perfectly smooth, and there is no peeling in any of the grids. 1: There is slight peeling of the film at the intersection of the cuts. 1: The percentage of peeling at the cross-cut area does not clearly exceed 5% of the total area of ​​the cross-cut section, which is 100% of the total area of ​​the cross-cut section. 2: There is small peeling along the edges of the cuts and / or at the intersections. The percentage of peeling at the cross-cut area clearly exceeds 5% but does not exceed 15% of the total area of ​​the cross-cut section, which is 100% of the total area of ​​the cross-cut section. 3: There is partial or complete peeling along the edges of the cuts and / or partial or complete peeling in several grids. The percentage of peeling at the cross-cut area clearly exceeds 15% but does not exceed 35% of the total area of ​​the cross-cut section, which is 100% of the total area of ​​the cross-cut section. 4: There is partial or complete large peeling along the edges of the cuts and / or complete large peeling in several grids. The percentage of peeling at the cross-cut area clearly exceeds 35% but does not exceed 65% of the total area of ​​the cross-cut section, which is 100% of the total area of ​​the cross-cut section. 5: Any of the following types of peeling that cannot be classified as Category 4.

[0197] (7-2) Visual Evaluation Before reliability testing in a high-temperature, high-humidity environment (i.e., 0 hours) and after the predetermined time, the appearance of each optically effective surface of resin optical elements that did not deform was visually observed to check for the presence or absence of cracks in the inorganic oxide film. The evaluation was performed according to the following criteria: A (Good): No cracks were observed. B (Fairly Good): A few cracks (about 1-2) were observed. C (Fairly Poor): Numerous cracks (about several to several dozen) were observed. D (Poor): Countless cracks were observed.

[0198] (7-3) Evaluation of Shape Retention Non-contact shape accuracy measurements were performed on biconvex lens molded products and resin optical elements made using said molded products under the following conditions. The shape accuracy measurements were performed on the surface on which the partially transparent film was deposited. This was because sufficient reflected light intensity could not be obtained on the surface on which the anti-reflective film was deposited, making measurement using this method difficult. Equipment used: NH-3SPs manufactured by Mitaka Kohki Measurement surface: Surface on which the partially transparent film was deposited Measurement location: Passing through the optical center of the optical element in a direction perpendicular to the flow After that, the obtained shape accuracy measurement results were evaluated according to the following criteria. A (Good): Absolute value of ΔPV is less than 2.0 μm B (Fairly Good): Absolute value of ΔPV is 2.0 μm or more and less than 5.0 μm C (Poor): Absolute value of ΔPV is 5.0 μm or more Here, ΔPV is the change in PV in the resin optical element (after film formation) with respect to the biconvex lens molded product (before film formation), and the Best Fit R value of the biconvex lens molded product (before film formation) was used in common for the calculation.

[0202]

[0199] [Supplement based on Rule 26, 13.05.2026]

[0200] The resin optical element of this embodiment has excellent adhesion between the optical thin film or inorganic oxide film formed on the optically effective surface and the resin surface layer, and maintains good adhesion and crack resistance even after high temperature and high humidity testing. Examples of suitable applications of the resin optical element of this embodiment include optical components in household goods, office automation equipment, AV equipment, battery electrical components, lighting equipment, etc., such as light guide plates, display front panels, and touch panels used in displays of smartphones, PDAs, tablet PCs, and LCD TVs; lenses and prisms used in smartphone and tablet PC camera lenses and bent optical system telephoto cameras (periscope cameras); VR (virtual reality) / AR (augmented reality) / MR (mixed reality) / XR (cross reality) head-mounted displays, LCD projectors, and near-infrared sensors (LiDAR; LightDetection And Optical components used in applications such as Ranging include, for example, prism elements, waveguides, freeform light guide members, lenses, especially small, thin-walled, and variable-thickness optical lenses; optical fibers, optical fiber coating materials, lenses and prisms for optical communication, lenses, Fresnel lenses, phase plates equipped with microlens arrays, optical cover components, substrates constituting polarization separation elements, polarizers and phase difference films, and substrates and lenses to which they are bonded. Optical components in automobiles include, for example, light guide plates for in-vehicle displays; optical covers composed of front panels and curved molded bodies used in in-vehicle meter panels, instrument clusters, car navigation systems, information displays, rear-seat displays, etc.; lenses and prisms, optical direction conversion elements, waveguides, light guides, combiners, dustproof sheets, optical cover components, etc. used in head-up displays; in-vehicle camera lenses (especially front lenses); and light guide rods. In addition to the above, it can also be preferably used in camera focus plates and components for digital signage display devices that transmit information to network-connected thin displays for advertising and promotional purposes in outdoor locations, stores, public institutions, transportation facilities, etc.

[0201] 11, 21, 31: Optically effective surface 12, 22, 32: Optical thin film 13, 23, 33: Inorganic oxide film 14, 24, 34: Resin surface layer 15: Resin substrate 111: Evaporation apparatus 112: Chamber 113: Resistive heating power supply 114: Evaporation dome 115: Boat 116: Shutter 117: Evaporation material 118: Substrate to be coated 119: Thin film 120: Evaporation apparatus 121: Chamber 122: Electron gun 123: Electron gun power supply 124: Evaporation dome 125: Crucible 126: Pole piece 127: Shutter 128: Backscattered electron trap 129: Evaporation material 130: Substrate 131: Thin film 132: Electron beam 133: Backscattered electron

Claims

1. A resin optical element having at least two optically effective surfaces, comprising a laminated structure comprising a resin substrate and an optical thin film, wherein the laminated structure is formed by sequentially forming the resin substrate, an inorganic oxide film, and the optical thin film, and the surface degradation index (I) of the tape-side peeled surface of the resin substrate on the optically effective surface, determined by X-ray photoelectron spectroscopy analysis. ｓｕｒｆ / I ｉｎｔ ) has the following relationship: 0.8 ≤ I ｓｕｒｆ / I ｉｎｔ ≤ 1 (where the normalized intensity of the peak originating from the C=O bond on the surface layer of the resin substrate is I) ｓｕｒｆ The normalized intensity of the peaks originating from the C=O bond in the resin substrate is I ｉｎｔ A resin-based optical element characterized by satisfying the following conditions.

2. A resin optical element having at least two optically effective surfaces formed of a laminated structure comprising a resin base material and an optical thin film, wherein the laminated structure is formed by sequentially forming the resin base material, an inorganic oxide film and the optical thin film, and a base material deterioration index (I ｓｕｒｆ / I ｉｎｔ ) on a base material-side peeled surface of the resin base material obtained by X-ray photoelectron spectroscopy analysis on said optically effective surface satisfies the following relationship: 0.80≦I ｓｕｒｆ / I ｉｎｔ ≦1.

00. The resin optical element characterized by satisfying the above condition.

3. Surface degradation index (I) of the tape-side peel surface of the resin substrate as determined by X-ray photoelectron spectroscopy analysis on the optically effective surface. ｓｕｒｆ / I ｉｎｔ ) has the following relationship: 0.70 ≤ I ｓｕｒｆ / I ｉｎｔ ≤ 1.00 (where the normalized intensity of the peak originating from the C=O bond on the surface layer of the resin substrate is I) ｓｕｒｆ The normalized intensity of the peaks originating from the C=O bond in the resin substrate is I ｉｎｔ A resin optical element according to claim 2, characterized in that it satisfies the following conditions.

4. The resin optical element according to claim 1 or 2, characterized in that the thickness of the inorganic oxide film is 300 to 500 nm.

5. The resin optical element according to claim 1 or 2, characterized in that the resin substrate contains a radical-decomposing resin having quaternary carbon in its main chain.

6. The resin optical element according to claim 1 or 2, characterized in that the inorganic oxide film contains one or more elements selected from the group consisting of silicon, aluminum, titanium, hafnium, zirconium, tantalum, cerium, and niobium.

7. The resin optical element according to claim 1 or 2, characterized in that the optical thin film is an anti-reflective film.

8. The resin optical element according to claim 1 or 2, wherein the optical thin film is a partial reflective film, the partial reflective film comprises a multilayer film obtained by alternately laminating five to nine layers of a high refractive index film having a refractive index of 1.90 to 2.46 and a low refractive index film having a refractive index of 1.44 to 1.60, the film thickness of the partial reflective film is smaller than the film thickness of the inorganic oxide film, the spectral reflectance of the partial reflective film in the wavelength range of 450 to 650 nm is 30% to 60%, and the difference between the maximum and minimum values ​​of the spectral reflectance is 2% to 10%.

9. The resin optical element according to claim 8, characterized in that the refractive index of the layer in contact with the inorganic oxide film among the multilayer films is 1.90 to 2.

20.

10. The resin optical element according to claim 9, characterized in that, when the layer in contact with the inorganic oxide film is considered the first layer of the multilayer film, the refractive index of the layers other than the first layer of the high refractive index film is greater than the refractive index of the first layer.

11. The resin optical element according to claim 8, characterized in that the refractive index of the low refractive index film among the multilayer films is smaller than the refractive index of the inorganic oxide film.

12. A method for manufacturing a resin optical element according to claim 1 or 2, comprising: a first film formation step of forming an inorganic oxide film with a thickness of 300 nm or more on a resin substrate with all optically effective surfaces by a dry film formation method that does not generate backscattered electrons in principle; and a second film formation step of forming the optical thin film by a film formation method that can generate backscattered electrons in principle.

13. The method for manufacturing a resin optical element according to claim 12, characterized in that the dry film formation method is a resistance heating deposition method and / or an electron beam bombarded indirect heating deposition method.

14. A method for suppressing surface layer degradation of a resin optical element, comprising a resin optical element having two or more laminated structures comprising a resin substrate and an optical thin film, characterized in that a first film deposition step is performed in which an inorganic oxide film of sufficient thickness to sufficiently shield against backscattered electrons is deposited on all of the resin substrates by a dry film deposition method that does not generate backscattered electrons in principle, thereby suppressing degradation of the surface layer of the surface due to collisions with backscattered electrons during a second film deposition step in which the optical thin film is deposited by a film deposition method that can generate backscattered electrons in principle.

Images