Method for manufacturing optical component

Abstract

Through the present invention, it is possible to provide a method for manufacturing an optical component, the method comprising a step for producing a molded body by molding a resin composition, and a step for forming an optical thin film on at least a portion of the surface of the molded body, wherein the resin composition contains a vinyl copolymer resin (A) including a constituent unit (a) represented by general formula (1) and a constituent unit (b) represented by general formula (2), and the step for forming the optical thin film comprises forming a SiOx layer (x is 1.5-2.0) having a thickness of 0.5-2.0 μm on a first layer by a resistance heating vapor deposition method, and furthermore forming a laminate in which a plurality of metal oxide layers and / or non-metal oxide layers are laminated by an electron beam vapor deposition method after a second layer.

Description

Optical component manufacturing method

[0001] The present invention relates to a method for manufacturing an optical component.

[0002] Transparent thermoplastic resins are lighter than glass and easier to mold into complex shapes, making them useful as optical component materials for cameras, displays, projectors, copiers, microscopes, and other devices. Transparent thermoplastic resin molded articles used in optical component applications often have optical thin films formed on their surfaces to provide optical functions such as anti-reflection mirrors, beam splitters, and filters. Among transparent thermoplastic resin materials, polymethyl methacrylate (PMMA) excels in transparency, optical isotropy, surface hardness, weather resistance, and moldability. However, when using the widely used vacuum deposition method using electron gun heating to form such optical thin films, problems arise, such as insufficient adhesion between the PMMA substrate and the optical thin film, resulting in easy peeling of the optical thin film. While vacuum deposition using resistance heating (Patent Document 1) and a film formation method that prevents reflected electrons generated by electron gun heating from reaching the substrate (Patent Document 2) improve initial adhesion between the PMMA substrate and the optical thin film, these methods can cause cracks and clouding in the optical thin film, as well as changes in dimensions and optical properties, in high-temperature, high-humidity environments, which can be problematic depending on the application. As a result, it has been difficult to obtain optical components that are excellent in transparency, optical isotropy, surface hardness, weather resistance, and moldability, and that also have excellent durability in high-temperature and high-humidity environments.

[0003] Japanese Patent Application Publication No. 7-63903 Patent No. 5280149

[0004] In view of the above circumstances, an object of the present invention is to solve at least one of the above-mentioned problems in the prior art. Another object of the present invention is to provide a method for producing an optical component that has excellent adhesion of an optical thin film and excellent durability in a high-temperature, high-humidity environment.

[0005] As a result of extensive research to solve the above problems, the present inventors have discovered that in the process of forming an optical thin film on a molded body, a specific SiO ｘIt has been found that the above-mentioned problems can be solved by forming a layer, and further forming a laminate in which a plurality of metal oxide layers and / or non-metal oxide layers are laminated as second and subsequent layers by electron beam deposition. That is, the present invention is as follows: <1> A method for producing an optical component, comprising the steps of: molding a resin composition to produce a molded body; and forming an optical thin film on at least a part of the surface of the molded body, wherein the resin composition contains a vinyl copolymer resin (A) containing a structural unit (a) represented by the following general formula (1) and a structural unit (b) represented by the following general formula (2): (In general formula (1), R1 represents a hydrogen atom or a methyl group, and R2 represents a group having 1 to 16 carbon atoms and having a hydrocarbon group, which may have a hydroxyl group or an alkoxy group. When a plurality of structural units (a) are present, the plurality of R1s and R2s may be the same or different.) (In general formula (2), R3 represents a hydrogen atom or a methyl group, and R4 represents a phenyl group, a cyclohexadienyl group, a cyclohexenyl group, or a cyclohexyl group, which may have at least one substituent selected from the group consisting of a hydrocarbon group having 1 to 4 carbon atoms, a hydroxyl group, an alkoxy group, and a halogen atom, and when a plurality of structural units (b) are present, the plurality of R3s and R4s may be the same or different.) The step of forming the optical thin film includes depositing a first layer of SiO ｘ <2> The method further comprises forming a layer (x is 1.5 to 2.0) of TiO 2 as a second or subsequent layer, and then forming a laminate of a plurality of metal oxide layers and / or non-metal oxide layers by electron beam deposition. ２ layer, and the non-metal oxide layer is SiO ２<3> The manufacturing method according to <1> above, wherein the laminate is a laminate of 2 to 20 metal oxide layers and / or non-metal oxide layers. <4> The manufacturing method according to <1> above, wherein the laminate has a thickness of 0.1 to 1 μm. <5> The manufacturing method according to <1> above, wherein the molded body has a thickness of 0.5 to 20 mm. <6> The manufacturing method according to <1> above, wherein in general formula (1), R1 and R2 represent methyl groups, and in general formula (2), R3 represents a hydrogen atom, and R4 represents an unsubstituted cyclohexyl group. <7> The manufacturing method according to <1> above, wherein the proportion of the structural unit (a) to the total of the structural units (a) and (b) is 30 to 80 mol %. <8> The step of forming the optical thin film comprises circulating oxygen gas under vacuum to adjust the absolute pressure to 0.01 to 0.04 PaA, and depositing a SiO 2 film having a thickness of 0.5 to 2.0 μm on the first layer by a resistance heating deposition method. ｘ The manufacturing method according to the above item <1>, further comprising forming a layer (x is 1.5 to 2.0).

[0006] According to the present invention, there is provided a method for producing an optical component having excellent adhesion of an optical thin film and excellent durability in a high-temperature, high-humidity environment. The optical component obtained by this production method can be suitably used for, for example, lenses, light guides, prisms, mirrors, beam splitters, filters, etc. for cameras, displays, projectors, copiers, microscopes, etc., and can be suitably used in particular for lenses for VR.

[0007] The present invention will be described in detail below. Note that the present invention is not limited to the following embodiments, and can be implemented by making any modifications within the scope of the effects of the invention.

[0008] <Molded Body Production Step> The method for producing an optical component of the present invention includes the steps of: molding a resin composition to produce a molded body; and forming an optical thin film on at least a portion of the surface of the molded body. Here, the resin composition contains a vinyl copolymer resin (A) including a structural unit (a) represented by the following general formula (1) and a structural unit (b) represented by the following general formula (2).

[0009] (In general formula (1), R1 represents a hydrogen atom or a methyl group, and R2 represents a group having 1 to 16 carbon atoms and having a hydrocarbon group, which may have a hydroxyl group or an alkoxy group. When a plurality of structural units (a) are present, the plurality of R1s and R2s may be the same or different.)

[0010] (In general formula (2), R3 represents a hydrogen atom or a methyl group, and R4 represents a phenyl group, a cyclohexadienyl group, a cyclohexenyl group, or a cyclohexyl group, which optionally has at least one substituent selected from the group consisting of a hydrocarbon group having 1 to 4 carbon atoms, a hydroxyl group, an alkoxy group, and a halogen atom, and when a plurality of structural units (b) are present, the plurality of R3s and R4s may be the same or different.)

[0011] The structural unit (a) is a structural unit derived from a (meth)acrylic acid ester monomer, which will be described later, and R1 is a hydrogen atom or a methyl group. Here, "(meth)acrylic acid" means "methacrylic acid and / or acrylic acid." Furthermore, R2 is a group having 1 to 16 carbon atoms and containing a hydrocarbon group, and may contain a hydroxyl group or an alkoxy group. Specific examples include alkyl groups such as methyl, ethyl, butyl, lauryl, stearyl, cyclohexyl, and isobornyl; hydroxyalkyl groups such as 2-hydroxyethyl, 2-hydroxypropyl, and 2-hydroxy-2-methylpropyl; alkoxyalkyl groups such as 2-methoxyethyl and 2-ethoxyethyl; and aryl groups such as benzyl and phenyl. In the vinyl copolymer resin (A), multiple R1s and R2s may be the same or different. Preferred structural units (a) are (meth)acrylate structural units in which R2 is a methyl group and / or an ethyl group, and more preferred are methyl methacrylate structural units in which R1 is a methyl group and R2 is a methyl group.

[0012] The structural unit (b) is represented by the general formula (2) above. The structural unit (b) in which R4 has a 6-membered ring other than a phenyl group can be obtained by the method for producing the vinyl copolymer resin (A) described below, i.e., by copolymerizing a (meth)acrylic acid ester monomer with an aromatic vinyl monomer described below and then hydrogenating the benzene ring in the aromatic vinyl monomer to produce the vinyl copolymer resin (A). When the benzene ring is hydrogenated, if the hydrogenation proceeds completely, the benzene ring becomes a cyclohexyl group, and if the hydrogenation proceeds only partially, the benzene ring becomes a cyclohexenyl group or a cyclohexadienyl group. It is also believed that there may be some structural units in which hydrogenation does not occur and the benzene ring, i.e., the phenyl group, remains. Examples of the hydrocarbon group having 1 to 4 carbon atoms include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, and a tert-butyl group, and the number of carbon atoms of the alkoxy group is usually 1 to 14, and specific examples thereof include a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group, an isobutoxy group, and a tert-butoxy group, and examples of the halogen atom include F, Cl, Br, and I. In the vinyl copolymer resin (A), a plurality of structural units (b) are usually present, and in this case, the plurality of R3s and R4s present may be the same or different.

[0013] Furthermore, the structural unit (b) may be a structural unit derived from an aliphatic vinyl monomer, as described below. That is, when the vinyl copolymer resin (A) is produced by copolymerizing a (meth)acrylic acid ester monomer and an aliphatic vinyl monomer as described below, the structural unit (b) is a structural unit derived from the aliphatic vinyl monomer.

[0014] In the vinyl copolymer resin (A), the hydrogenation rate of the benzene rings in the structural unit (b) is preferably 80% or more. If the hydrogenation rate is less than 80%, transparency may decrease. It is more preferably 90% or more, and even more preferably 95% or more. A hydrogenation rate of the benzene rings in the structural unit (b) of 80% or more means that, of all R4s in the structural unit (b), the proportion of R4s that are cyclohexadienyl groups, cyclohexenyl groups, or cyclohexyl groups, which may have a substituent, is 80% or more. A proportion of 80% or more means, for example, that when there are 100 structural units (b), 80 or more of the 100 R4s are cyclohexadienyl groups, cyclohexenyl groups, or cyclohexyl groups.

[0015] The degree of hydrogenation can be determined from the rate of decrease in absorbance at 260 nm (corresponding to the absorption of benzene rings) in UV spectrum measurement of the resin before and after the hydrogenation reaction.

[0016] The vinyl copolymer resin (A) is primarily composed of structural units (a) and (b). The proportion of structural unit (a) is preferably in the range of 30 to 80 mol % relative to the total of structural units (a) and (b), and more preferably in the range of 60 to 80 mol %. If the proportion of structural unit (a) relative to the total of structural units (a) and (b) is less than 30 mol %, the surface hardness and adhesion to the hard coat paint may decrease, making it impractical. On the other hand, if the proportion exceeds 80 mol %, the optical thin film may crack or become cloudy in a high-temperature, high-humidity environment, or its dimensions and optical properties may change, making it impractical.

[0017] The vinyl copolymer resin (A) is not particularly limited, and is preferably a resin obtained by copolymerizing a (meth)acrylic acid ester monomer with an aromatic vinyl monomer and then hydrogenating the aromatic double bond derived from the aromatic vinyl monomer, or a resin obtained by copolymerizing a (meth)acrylic acid ester monomer with an aliphatic vinyl monomer, with the former being particularly preferred.

[0018] The (meth)acrylic acid ester monomer used in this case preferably has 4 to 20 carbon atoms. The (meth)acrylic acid ester monomer having 4 to 20 carbon atoms is not particularly limited, but specific examples include methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, lauryl (meth)acrylate, stearyl (meth)acrylate, cyclohexyl (meth)acrylate, isobornyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxy-2-methylpropyl (meth)acrylate, 2-methoxyethyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate, benzyl (meth)acrylate, phenyl (meth)acrylate, and 2-(meth)acryloyloxyethyl phosphorylcholine. Among these, methyl methacrylate is preferred.

[0019] Specific examples of the aromatic vinyl monomer include styrene, α-methylstyrene, o-methylstyrene, p-hydroxystyrene, alkoxystyrene, chlorostyrene, and derivatives thereof, of which styrene and α-methylstyrene are preferred.

[0020] Specific examples of the aliphatic vinyl monomer include vinylcyclohexane, isopropenylcyclohexane, 1-isopropenyl-2-methylcyclohexane, etc. Among these, vinylcyclohexane is preferred.

[0021] A method for copolymerizing a (meth)acrylic acid ester monomer with an aromatic vinyl monomer and then hydrogenating the aromatic double bond derived from the aromatic vinyl monomer will be described below. A known method can be used for polymerizing the (meth)acrylic acid ester monomer with the aromatic vinyl monomer, and the vinyl copolymer resin (A) can be produced by, for example, bulk polymerization, suspension polymerization, or solution polymerization. The solution polymerization method involves continuously supplying a monomer composition containing a monomer, a chain transfer agent, and a polymerization initiator to a complete mixing vessel and continuously polymerizing the monomer at 100 to 180°C.

[0022] Examples of the solvent to be used in this case include hydrocarbon solvents such as toluene, xylene, cyclohexane, and methylcyclohexane; ester solvents such as ethyl acetate and methyl isobutyrate; ketone solvents such as acetone and methyl ethyl ketone; ether solvents such as tetrahydrofuran and dioxane; and alcohol solvents such as methanol and isopropanol.

[0023] The hydrogenation reaction of the aromatic double bond after the polymerization of the (meth)acrylic acid ester monomer and the aromatic vinyl monomer is preferably carried out in a solvent. The solvent used for this hydrogenation reaction may be the same as or different from the polymerization solvent. Examples of the solvent include hydrocarbon solvents such as cyclohexane and methylcyclohexane; ester solvents such as ethyl acetate and methyl isobutyrate; ketone solvents such as acetone and methyl ethyl ketone; ether solvents such as tetrahydrofuran and dioxane; and alcohol solvents such as methanol and isopropanol.

[0024] The hydrogenation method is not particularly limited, and known methods can be used. For example, the hydrogenation can be carried out in a batch or continuous flow system at a hydrogen pressure of 3 to 30 MPa and a reaction temperature of 60 to 250°C. By setting the temperature at 60°C or higher, the reaction time does not become too long, and by setting the temperature at 250°C or lower, scission of molecular chains and hydrogenation of ester moieties are less likely to occur.

[0025] Examples of the catalyst used in the hydrogenation reaction include solid catalysts in which a metal such as nickel, palladium, platinum, cobalt, ruthenium, or rhodium, or an oxide, salt, or complex compound of such a metal, is supported on a porous carrier such as carbon, alumina, silica, silica-alumina, zirconia, or diatomaceous earth.

[0026] The polymerization of the (meth)acrylic acid ester monomer and the aliphatic vinyl monomer can be carried out by a known method, for example, the method described in JP-A Nos. 63-3011 and 63-170475.

[0027] The resin composition containing the vinyl copolymer resin (A) of the present invention may contain other resins as long as the transparency is not impaired. Examples of other resins that may be contained in the resin composition include methyl methacrylate / styrene copolymer resin, methyl methacrylate / styrene / maleic anhydride copolymer resin, styrene / methacrylic acid copolymer resin, styrene / maleic anhydride copolymer resin, polymethyl methacrylate, polystyrene, norbornene resin, and polycarbonate.

[0028] Various additives can be mixed with the vinyl copolymer resin (A). Examples of additives include ultraviolet absorbers, antioxidants, anti-coloring agents, anti-static agents, release agents, lubricants, dyes, pigments, and impact resistance agents. The mixing method is not particularly limited, and methods such as compounding the entire amount, dry blending a masterbatch, and dry blending the entire amount can be used.

[0029] The molded article used in the present invention is obtained by molding the above-mentioned resin composition, but may be obtained by any molding method. Examples of molding methods include known methods such as injection molding, extrusion molding, heat pressing, solvent casting, and inflation. In the present invention, the thickness of the molded article is preferably 0.5 to 20 mm, and more preferably 1 to 10 mm.

[0030] <Optical Thin Film Forming Process> The process of forming an optical thin film in the present invention involves forming a 0.5-2.0 μm thick SiOx layer (x is 1.5-2.0) as a first layer by resistance heating vapor deposition, and then forming a laminate of multiple metal oxide layers and / or non-metal oxide layers by electron beam vapor deposition as second and subsequent layers. When forming the first layer, oxygen gas is circulated under vacuum, and the absolute pressure is preferably adjusted to 0.01-0.04 PaA, and more preferably 0.02-0.03 PaA. Note that absolute pressure means "pressure defined relative to a complete vacuum (absolute vacuum)" and is expressed by the following relationship: When an optical thin film is formed on the surface of a molded product using an electron beam, the polymethyl methacrylate (PMMA) that constitutes the molded product is decomposed and deteriorated by the electron beam, but in the present invention, an SiOx layer is formed on the surface of the molded product as the first layer by resistance heating deposition, which prevents PMMA from being affected by the electron beam, thereby improving adhesion when forming an optical thin film on the surface of the molded product.

[0031] In the present invention, SiO ｘ A commonly known method can be used to form the layer, i.e., a thin film can be formed by passing a current through a resistor made of W, Mo, B, or the like in a vacuum deposition apparatus to generate heat and evaporate the deposition material.

[0032] In the present invention, the SiO formed in the first layer ｘ The thickness of the layer is 0.5 to 2.0 μm, preferably 0.7 to 1.8 μm, and more preferably 0.9 to 1.6 μm. ｘ If the thickness of the layer is less than 0.5 μm, the adhesion of the optical thin film is poor, and peeling occurs in the adhesion evaluation test described later. ｘ If the layer thickness exceeds 2.0 μm, it becomes difficult to form the second and subsequent layers, as will be shown in Comparative Example 2 described later.

[0033] In the present invention, the SiO formed in the first layer ｘ In the layer, x is 1.5 to 2.0. If x is less than 1.5, discoloration occurs after a high-temperature, high-humidity environmental test, as shown in Comparative Example 3 described later.

[0034] In the present invention, a generally known method can be used to form a laminate of multiple metal oxide layers and / or non-metal oxide layers by electron beam deposition for the second and subsequent layers, i.e., to form a thin film by irradiating a deposition material with electrons focused by an electron gun, heating and evaporating the material.

[0035] The metal oxide layer is a layer containing a metal oxide. Specific examples of metal oxides include titanium oxide, aluminum oxide, zirconium oxide, cerium oxide, bismuth oxide, chromium oxide, iron oxide, hafnium oxide, thallium oxide, tantalum pentoxide, iridium oxide, tungsten oxide, molybdenum oxide, lanthanum oxide, magnesium oxide, samarium oxide, antimony oxide, scandium oxide, tin oxide, yttrium oxide, europium oxide, and zinc oxide. Among these, titanium oxide is preferred. The non-metal oxide layer is a layer containing a non-metal oxide. Specific examples of non-metal oxides include silicon oxide.

[0036] In the present invention, the metal oxide layer is TiO ２ layer, and the non-metal oxide layer is SiO ２ In a preferred embodiment, the laminate is a laminate of 2 to 20 metal oxide layers and / or non-metal oxide layers, more preferably 4 to 15 layers, and particularly preferably 5 to 12 layers. The thickness of the laminate is preferably 0.1 to 1 μm, and more preferably 0.1 to 0.5 μm.

[0037] The optical component obtained as described above has excellent durability in high-temperature and high-humidity environments, and can be suitably used for, for example, lenses for cameras, displays, projectors, copiers, microscopes, etc., light guides, prisms, mirrors, beam splitters, filters, etc. In particular, it can be suitably used for lenses for VR.

[0038] The present invention will be described below with reference to examples, but the present invention is not limited to these examples in any way.

[0039] <Evaluation of Initial Adhesion> A sample having an optical thin film formed on one side of a molded article was left to stand for 24 hours or more in an environment of 23°C and 50% relative humidity to condition it. Cellophane tape (CT-15 manufactured by Nichiban Co., Ltd.) was rubbed with a finger onto the surface of the optical thin film to adhere it, and the cellophane tape was quickly peeled off at a right angle. The same procedure was repeated three times, and the sample in which the optical thin film peeled off the first time was ranked C, the sample in which the optical thin film peeled off the second or third time was ranked B, and the sample in which the optical thin film did not peel off was ranked A.

[0040] <Evaluation of Adhesion After Environmental Testing> A sample having an optical thin film formed on one side of a molded article was placed in a thermo-hygrostat chamber set at a temperature of 65°C and a relative humidity of 90% for 96 hours, and then the sample was removed from the thermo-hygrostat chamber and conditioned in an environment at a temperature of 23°C and a relative humidity of 50% for 1 hour. In a tape test similar to that used to evaluate initial adhesion, samples that peeled on the first try were ranked C, samples that peeled on the second or third try were ranked B, and samples that did not peel were ranked A.

[0041] <Durability Evaluation> A sample having an optical thin film formed on one side of a molded article was left to condition in an environment at a temperature of 23°C and a relative humidity of 50% for 24 hours or more. After being placed in a thermo-hygrostat chamber set at a temperature of 65°C and a relative humidity of 90% for 96 hours, the sample was removed from the thermo-hygrostat chamber and placed in an environment at a temperature of 23°C and a relative humidity of 50% for 24 hours. The sample surface was observed under an optical microscope at 100x magnification, and samples that were found to have no appearance abnormalities such as cracks and that showed peeling of the optical thin film on the first try in a tape test similar to the above evaluation were ranked C, those that showed peeling on the second or third try were ranked B, and those that showed no peeling of the optical thin film were ranked A.

[0042] <Optical Property Evaluation> The optical properties (transmittance, haze) of the sample in which an optical thin film was formed on one side of the molded article were also measured using a spectroscopic haze meter SH7000 manufactured by Nippon Denshoku Industries Co., Ltd. The optical properties were further measured after the above-mentioned constant temperature and humidity test. For transmittance, the average rate of change at wavelengths of 380 nm to 780 nm was calculated, and a value of less than 3% was ranked A, 3% or more but less than 5% was ranked B, and 5% or more was ranked C. For haze, the amount of haze change before and after the constant temperature and humidity test was calculated, and a haze change of less than 0.1 was ranked A, 0.1 or more but less than 0.3 was ranked B, and 0.3 or more was ranked C.

[0043] <Overall Evaluation> A rating of A in all of the above initial adhesion evaluation, adhesion evaluation after environmental testing, durability evaluation, and optical property evaluation was deemed to be a pass as an overall evaluation, and a rating of B or C was deemed to be a fail as an overall evaluation.

[0044] Synthesis Example 1 [Production of vinyl copolymer resin] A copolymer resin (A1') of 75 mol% methyl methacrylate and 25 mol% styrene was dissolved in methyl isobutyrate to prepare a 10% by mass methyl isobutyrate solution. 500 parts by mass of the 10% by mass methyl isobutyrate solution of copolymer resin (A1') and 1 part by mass of 10% by mass Pd / C were charged into a 1000 mL autoclave, and the benzene ring moiety was hydrogenated by holding at 200°C under a hydrogen pressure of 9 MPa for 15 hours. The catalyst was removed using a filter, and the mixture was introduced into a solvent removal apparatus to obtain a pellet-shaped vinyl copolymer resin (A1). １ Measurement by H-NMR revealed that the proportion of methyl methacrylate structural units was 75 mol %, and measurement of absorbance at a wavelength of 260 nm revealed that the hydrogenation reaction rate of the benzene ring moiety was 99%.

[0045] Synthesis Example 2 [Production of Vinyl Copolymer Resin] A vinyl copolymer resin (A2) was obtained in the same manner as in Synthesis Example 1, except that a copolymer resin (A2′) of 63 mol % of methyl methacrylate and 37 mol % of styrene was used instead of the copolymer resin (A1′) used in Synthesis Example 1. １ Measurement by H-NMR revealed that the proportion of methyl methacrylate structural units was 63 mol %, and measurement of absorbance at a wavelength of 260 nm revealed that the hydrogenation reaction rate of the benzene ring moiety was 99%.

[0046] Example 1 The vinyl copolymer resin (A1) obtained in Synthesis Example 1 was injection molded to prepare a molded body (B1) in the shape of a flat plate (82 mm x 65 mm x 3 mm in thickness). Oxygen gas was circulated under vacuum to adjust the absolute pressure to 0.02 PaA, and a 0.5 μm thick SiO 2 film was deposited on one side of the molded body (B1) as a first layer by resistance heating deposition. ｘ Next, the first layer of SiO ｘ On the layer, a second layer of TiO ２ The third layer is SiO ２ , the fourth layer is TiO２ , the fifth layer is SiO ２ , the sixth layer is TiO ２ The seventh layer is SiO ２ A laminate (laminate thickness: 0.5 μm) was formed by electron beam deposition to manufacture an optical component. The results of the initial adhesion evaluation, durability evaluation, and optical property evaluation of the obtained optical component are shown in Table 1 below (the same applies hereinafter). The optical component obtained in Example 1 was ranked A in all evaluations, and the overall evaluation was pass.

[0047] (Example 2) The first layer in Example 1 was replaced with a 1.0 μm thick SiO ｘ Except for using a layer (x = 1.5 to 2.0), an optical component was manufactured in the same manner as in Example 1. The optical component obtained in Example 2 was ranked A in all evaluations, and the overall evaluation was pass.

[0048] (Example 3) The first layer in Example 1 was replaced with a 2.0 μm thick SiO ｘ Except for using a layer (x = 1.5 to 2.0), an optical component was manufactured in the same manner as in Example 1. The optical component obtained in Example 3 was ranked A in all evaluations, and the overall evaluation was pass.

[0049] Example 4 The vinyl copolymer resin (A2) obtained in Synthesis Example 2 was injection molded to prepare a molded product (B2) in the shape of a flat plate (82 mm x 65 mm x 3 mm in thickness). Oxygen gas was circulated under vacuum to adjust the absolute pressure to 0.02 PaA, and a 0.5 μm thick SiO 2 film was deposited as a first layer on one side of the molded product (B2) by resistance heating deposition. ｘ Next, the first layer of SiO ｘ On the layer, a second layer of TiO ２ The third layer is SiO ２ , the fourth layer is TiO ２ The fifth layer is SiO ２ , the sixth layer is TiO ２ The seventh layer is SiO ２A laminate (laminate thickness: 0.5 μm) was formed by electron beam deposition to produce an optical component. The optical component obtained was subjected to an initial adhesion evaluation, an adhesion evaluation after an environmental test, a durability evaluation, and an optical property evaluation, and the results are shown in Table 1 below (the same applies hereinafter). The optical component obtained in Example 4 was ranked A in all evaluations, and the overall evaluation was pass.

[0050] (Example 5) The first layer in Example 4 was replaced with a 1.0 μm thick SiO ｘ An optical component was manufactured in the same manner as in Example 4, except that the optical component obtained in Example 5 was made into a multi-layer structure (x = 1.5 to 2.0). The optical component obtained in Example 5 was ranked A in all evaluations, and the overall evaluation was pass.

[0051] (Example 6) The first layer in Example 4 was replaced with a 2.0 μm thick SiO ｘ Except for using a layer (x = 1.5 to 2.0), an optical component was manufactured in the same manner as in Example 4. The optical component obtained in Example 6 was ranked A in all evaluations, and the overall evaluation was pass.

[0052] Comparative Example 1 The vinyl copolymer resin (A1) obtained in Synthesis Example 1 was injection molded to prepare a molded product (B1) having a plate shape (82 mm x 65 mm x 3 mm in thickness). A first layer of TiO ２ The second layer is SiO ２ , the third layer is TiO ２ The fourth layer is SiO ２ , the fifth layer is TiO ２ The sixth layer is SiO ２ A laminate (laminate thickness: 0.5 μm) was formed to produce an optical component. A low-reflection electron gun was used to heat the film raw material, and the electrons generated were deflected and captured by a magnetic field so as not to reach the molded body (B1) during film formation. The optical component obtained in Comparative Example 1 was ranked A in the initial adhesion evaluation, durability evaluation, and optical property evaluation, and ranked C in the adhesion evaluation after the environmental test, resulting in an overall failure.

[0053] Comparative Example 2 An optical component was produced in the same manner as in Comparative Example 1, except that the vinyl copolymer resin (A2) obtained in Synthesis Example 2 was used instead of the vinyl copolymer resin (A1) obtained in Synthesis Example 1. The optical component obtained in Comparative Example 2 received an A rank in the initial adhesion evaluation, durability evaluation, and optical property evaluation, and a C rank in the adhesion evaluation after the environmental test, resulting in an overall failure.

[0054] (Comparative Example 3) The first layer in Example 1 was replaced with a 3.0 μm thick SiO ｘ An attempt was made to manufacture an optical component in the same manner as in Example 1, except that the number of layers was 1.5 to 2.0. However, it was difficult to form the second and subsequent layers, and the overall evaluation was unsuccessful.

[0055] (Comparative Example 4) SiO of the first layer in Example 5 ｘ An optical component was manufactured in the same manner as in Example 5, except that the layer had x = 1.0 or more and less than 1.5, and the absolute pressure in the resistance heating vapor deposition method was 0.01 PaA. The optical component obtained in Comparative Example 4 was ranked A in the initial adhesion evaluation, durability evaluation, and optical property evaluation, and ranked C in the adhesion evaluation after the environmental resistance test, and the overall evaluation was unsuccessful.

[0056] (Comparative Example 5) SiO of the first layer in Example 5 ｘ An optical component was manufactured in the same manner as in Example 5, except that the layer had x = 1.0 or more and less than 1.5, and the absolute pressure in the resistance heating vapor deposition method was 0.04 PaA. The optical component obtained in Comparative Example 5 was ranked A in the initial adhesion evaluation, adhesion evaluation after environmental resistance test, and average transmittance change rate in the optical property evaluation, and ranked C in the durability evaluation and haze before environmental test in the optical property evaluation, and the overall evaluation was unacceptable.

[0057] (Comparative Example 6) The first layer of SiO in Example 2 ｘ An optical component was manufactured in the same manner as in Example 2, except that the layer had x = 1.0 or more and less than 1.5, and the absolute pressure in the resistance heating vapor deposition method was 0.04 PaA. The optical component obtained in Comparative Example 6 was ranked A in the initial adhesion evaluation, adhesion evaluation after environmental testing, and average transmittance change rate in the optical property evaluation, and ranked C in the durability evaluation and haze before environmental testing in the optical property evaluation, and the overall evaluation was unacceptable.

[0058]

Claims

1. A method for producing an optical component, comprising: a step of molding a resin composition to produce a molded body; and a step of forming an optical thin film on at least a portion of the surface of the molded body, wherein the resin composition contains a vinyl copolymer resin (A) containing a structural unit (a) represented by the following general formula (1) and a structural unit (b) represented by the following general formula (2), (In general formula (1), R1 represents a hydrogen atom or a methyl group, and R2 represents a group having 1 to 16 carbon atoms and having a hydrocarbon group, and may have a hydroxyl group or an alkoxy group. When a plurality of structural units (a) are present, the plurality of R1s and R2s may be the same or different.) (In general formula (2), R3 represents a hydrogen atom or a methyl group, R4 represents a phenyl group, a cyclohexadienyl group, a cyclohexenyl group or a cyclohexyl group, which may have at least one substituent selected from the group consisting of a hydrocarbon group having 1 to 4 carbon atoms, a hydroxyl group, an alkoxy group and a halogen atom, and when a plurality of structural units (b) are present, the plurality of R3's and R4's may be the same or different. ） 　 The step of forming the optical thin film is a step of forming a first layer of SiO ｘ and further forming a laminate comprising a plurality of metal oxide layers and / or non-metal oxide layers as second and subsequent layers by electron beam deposition.

2. The metal oxide layer is TiO ２ layer, and the non-metal oxide layer is SiO ２ The method of claim 1 , wherein the layer is a layer.

3. The method according to claim 1, wherein the laminate comprises 2 to 20 metal oxide layers and / or non-metal oxide layers.

4. The manufacturing method according to claim 1, wherein the thickness of the laminate is 0.1 to 1 μm.

5. The manufacturing method according to claim 1, wherein the thickness of the molded body is 0.5 to 20 mm.

6. The method according to claim 1, wherein in said general formula (1), R1 and R2 represent methyl groups, and in said general formula (2), R3 represents a hydrogen atom, and R4 represents an unsubstituted cyclohexyl group.

7. The method according to claim 1, wherein the proportion of the structural unit (a) to the total of the structural units (a) and (b) is 30 to 80 mol %.

8. The step of forming the optical thin film is carried out by circulating oxygen gas under vacuum to adjust the absolute pressure to 0.01 to 0.04 PaA, and depositing a SiO film having a thickness of 0.5 to 2.0 μm on the first layer by resistance heating deposition. ｘ The method of claim 1 comprising forming a layer (x is 1.5 to 2.0).

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