JP2008185759A - Optical article - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical article which has an antireflection effect and also is excellent in water resistance, alkali resistance and scuffing resistance. <P>SOLUTION: The optical article comprises an organic layer consisting of a first composition containing hollow silica particulates having inner cavities and an organic silicon compound and an organic layer consisting of a second composition containing a tetrafunctional organic silicon compound of a non-fluorine system expressed by formula (1): R<SP>1</SP>R<SP>2</SP><SB>n</SB>SiX<SP>1</SP><SB>3-n</SB>, wherein R<SP>1</SP>is an organic group having a polymerizable reaction group, R<SP>2</SP>is a 1-6C hydrocarbon group, X<SP>1</SP>is a hydrolyzable group and (n) is 0 or 1. The organic layer consisting of the first composition is constituted of one layer which is formed on a base material directly or via a primary layer constituted of at least one layer, which has a lower refractive index than that of the base material or the primary layer and has refractive index difference of 0.1 or more toward the base material or the primary layer. The organic layer consisting of the second composition is constituted of one layer which is formed on a surface of the layer consisting of the first composition. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an optical article having an antireflection effect.

  In an optical article such as an optical lens, a spectacle lens, or a recording medium, when surface reflection occurs, the transmittance of the optical system is lowered, the light contributing to imaging is reduced, and the contrast of the image is lowered. For this reason, it is important to apply an antireflection process to the optical article. As antireflection processing, it has been studied to form a low refractive index layer having a lower refractive index than that of the base material or the base layer directly on the base material or via a base layer composed of at least one layer.

Patent Document 1 discloses a plastic lens having excellent heat resistance and sufficient antireflection function. In this plastic lens, a low refractive index layer having a refractive index lower by 0.10 or more than the refractive index of the outermost layer of the plastic lens substrate is provided on the plastic lens substrate by a wet method with a film thickness of 50 nm to 150 nm. ing. An example of the low refractive index layer includes an organic layer containing the following components (A) and (B).
(A) Organosilicon compound represented by the following general formula (0) R ¹¹ R ¹² _p SiX ¹¹ _3-p (0)
(In the formula, R ¹¹ is an organic group having a polymerizable reactive group, R ¹² is a hydrocarbon group having 1 to 6 carbon atoms, X ¹¹ is a hydrolytic group, and p is 0 or 1. .)
(B) Silica-based fine particles having internal cavities
JP-A-2003-222703

  In order to improve the antireflection effect, it is necessary to increase the difference in refractive index between the low refractive index layer and the base material or base layer that is the base. For that purpose, it is desirable to make the low refractive index layer further lower in refractive index. For example, in order to achieve a further lower refractive index in the organic layer containing the components (A) and (B) as described above, the component (B) (silica-based fine particles having internal cavities) Hereinafter, it is necessary to increase the content (% by weight) of hollow silica fine particles. However, when the content of the hollow silica fine particles is increased, the content of the component (A) (organosilicon compound) that functions as a binder decreases, and durability including water resistance and alkali resistance and hardness including scratch resistance. Tends to decrease.

  Similarly to the inorganic low refractive index layer, the refractive index can be lowered by adopting a multilayer structure of a high refractive index layer and a low refractive index layer. However, in order to obtain the antireflection effect, it is necessary to precisely control the film thickness of all these multilayers, and the merit of the organic low refractive index layer that can be formed by a simple method such as immersion cannot be utilized. .

  As described above, in the organic low refractive index layer, it is difficult to achieve both antireflection function and durability.

One embodiment of the present invention is formed directly on a substrate or through an underlayer composed of at least one layer, has a refractive index lower than that of the substrate or the underlayer, and has a refractive index difference with respect to the substrate or the underlayer at least. 0.1 organic layer formed on the surface of a layer composed of a first composition containing hollow silica fine particles having internal cavities and an organosilicon compound, and a layer composed of the first composition. And an organic layer comprising a second composition comprising a non-fluorine-based tetrafunctional organosilicon compound represented by the following general formula (1): .
R ¹ R ² _n SiX ¹ _3-n (1)
However, in formula (1), R ¹ is an organic group having a polymerizable reactive group, R ² is a hydrocarbon group having 1 to 6 carbon atoms, X ¹ is a hydrolytic group, and n is 0. Or it is 1.

  The layer composed of the first composition containing hollow silica fine particles having internal cavities and an organosilicon compound can be easily made to have a lower refractive index than the base material or the base layer, and the refractive index relative to the base material or the base layer. The difference can be 0.1 or more. For this reason, the effect which suppresses the reflection in the optical article surface is acquired. That is, the layer made of the first composition can be formed by an immersion method or the like, and functions as a single layer and an antireflection layer.

  On the other hand, since the layer composed of the second composition containing the non-fluorine-based tetrafunctional organosilicon compound is a layer mainly composed of the organosilicon compound, it is easy to ensure durability and hardness even if the film thickness is small. Therefore, the layer made of the second composition functions as a reinforcing layer that reinforces the layer made of the first composition (organic antireflection layer). Therefore, even if the content of the hollow silica fine particles in the layer made of the first composition is increased to further reduce the refractive index, the structure including the layer made of the second composition has water resistance and alkali resistance. Sufficient durability including sufficient hardness and sufficient hardness including scratch resistance can be obtained. Furthermore, non-fluorine tetrafunctional organosilicon compounds do not contain fluorine atoms that hinder reactivity with organic antireflection layers, so adhesion strength is improved and durability and scratch resistance can be improved. It becomes. In addition, since it is tetrafunctional, the reactivity with the antireflection layer is improved.

  The layer made of the second composition is an organic layer and can be formed by a dipping method or the like. Further, by providing this layer, the refractive index of the layer made of the first composition can be lowered, so that the layer has a sufficient antireflection function. For this reason, it is not necessary to lower the refractive index by combining the layer made of the first composition and the layer made of the second composition, and when these layers are formed, highly accurate film thickness control is performed. do not need.

In this optical article, the film thickness d of the layer (reinforcing layer) made of the second composition preferably satisfies the following condition (2).
10 nm ≦ d ≦ 30 nm (2)

  When the film thickness d of the layer composed of the second composition (reinforcing layer) is less than 10 nm, the effect (reinforcing effect) of protecting the layer composed of the first composition (organic antireflection layer) is sufficiently high. It is difficult to obtain. Further, if the thickness d of the reinforcing layer is about 10 to 30 nm, the function as the reinforcing layer can be sufficiently obtained, and if the thickness exceeds the thickness, there is a possibility of optically affecting the optical article, which is not preferable.

  A reinforcement layer consists of a 2nd composition containing the non-fluorine-type tetrafunctional organosilicon compound shown by the said General formula (1). Since the tetrafunctional organosilicon compound is three-dimensionally crosslinked to form a reinforcing layer, it is effective in improving durability such as water resistance and alkali resistance and scratch resistance. Further, the reinforcing layer may contain silica fine particles or metal oxide fine particles that are not hollow as long as the diameter is smaller than the film thickness. That is, when the reinforcing layer includes fine particles such as silica fine particles that are not hollow, the particle size of the fine particles is preferably 30 nm or less.

In this optical article, the layer (organic antireflection layer) made of the first composition preferably contains 20 to 90% by weight of hollow silica fine particles. By containing in the said range, since it becomes possible to make a refractive index still lower, an antireflection characteristic improves more. Furthermore, since a reinforcing layer is formed on the surface, even if the organic antireflection layer contains 20% by weight or more of hollow silica fine particles, the combination of these layers provides water resistance and alkali resistance. Durability and hardness are sufficiently obtained. However, if it exceeds 90% by weight, the binder content decreases, and it becomes difficult to obtain durability and hardness.

In this optical article, the non-fluorine tetrafunctional organosilicon compound contained in the second composition for forming the reinforcing layer is particularly limited as long as it is represented by the following general formula (1). It is not a thing.
R ¹ R ² _n SiX ¹ _3-n (1)
However, in formula (1), R ¹ is an organic group having a polymerizable reactive group, R ² is a hydrocarbon group having 1 to 6 carbon atoms, X ¹ is a hydrolytic group, and n is 0. Or it is 1.

In the above formula (1), R ¹ is an organic group having a polymerizable reactive group, and specific examples thereof are vinyl group, allyl group, acrylic group, methacryl group, epoxy group, mercapto group, cyano group, amino group. Groups and the like. R ² is a hydrocarbon group having 1 to 6 carbon atoms, and specific examples thereof include a methyl group, an ethyl group, a butyl group, a vinyl group, and a phenyl group. X ¹ is a hydrolyzable functional group, and specific examples thereof include alkoxy groups such as methoxy group, ethoxy group, and methoxyethoxy group, halogen groups such as chloro group and bromo group, and acyloxy groups.

  Examples of the non-fluorinated tetrafunctional organosilicon compound represented by the formula (1) include tetramethoxysilane, vinyltrialkoxysilane, vinyltrichlorosilane, vinyltri (β-methoxy-ethoxy) silane, allyltrialkoxysilane, Acrylicoxypropyltrialkoxysilane, methacryloxypropyltrialkoxysilane, methacryloxypropyl dialkoxymethylsilane, β- (3,4-epoxycyclohexyl) -ethyltrialkoxysilane, mercaptopropyltrialkoxysilane, γ-aminopropyltrialkoxy Examples thereof include silane, N-β (aminoethyl) -γ-aminopropylmethyl dialkoxysilane, tetraalkoxysilane, and γ-glycidoxypropyltrimethoxysilane. The non-fluorine tetrafunctional organosilicon compound contained in the second composition preferably contains tetramethoxysilane.

In this optical article, the organosilicon compound contained in the first composition for forming the layer composed of the first composition is not particularly limited. For example, it is represented by the following general formula (2). Can be used.
R ³ R ⁴ _m SiX ² _3-m (2)
However, in the formula (2), R ³ is an organic group having a polymerizable reactive group, R ⁴ is a hydrocarbon group having 1 to 6 carbon atoms, X ² is a hydrolytic group, and m is 0. Or it is 1.

In the above formula (2), R ³ is an organic group having a polymerizable reactive group.
It is similar to R ¹ in the above (1), and R ³ of the above (2), the formula (1) R ¹ and may be be the same or different. R ⁴ is a hydrocarbon group having 1 to 6 carbon atoms.
(1) it is the same as R ² of formula, and R ⁴ of the above (2), the equation (1) R ² and may be be the same or different. X ² is a hydrolyzable functional group, and specific examples are the same as X ^{1 in the} above formula (1), but X ² in the above formula (2) and X ^{1 in the} above formula (1) May be the same or different.

  Therefore, the specific example of the organosilicon compound represented by the above formula (2) is the same as the specific example of the organosilicon compound represented by the above formula (1), but the organosilicon compound contained in the first composition And the organosilicon compound contained in the second composition may be the same or different.

The organosilicon compound contained in the first composition for forming the layer composed of the first composition may be used by mixing two or more kinds of compounds. Further, it is more effective to use the organosilicon compound contained in the composition for forming the layer after hydrolysis.

  In order to lower the refractive index of the layer composed of the first composition and enhance the antireflection effect, hollow silica fine particles (hollow spherical silica-based fine particles having internal cavities in which cavities are formed inside the silica-based fine particles ) Is preferably used. This is because in the case of hollow silica fine particles having an internal cavity, a reduction in the refractive index is achieved by the gas being contained in the cavity formed inside.

  As the hollow silica fine particles having internal cavities contained in the first composition for forming the layer made of the first composition, for example, silica sol made of silica-based fine particles having a particle diameter of 10 to 1000 nm can be used. . As the silica sol, a dispersion in a colloidal form in an organic solvent such as water, alcohols, cellosolves, or the like can be used.

  In addition to the organosilicon compound, the first and second compositions include various resins such as polyurethane resins, epoxy resins, melamine resins, polyolefin resins, urethane acrylate resins, epoxy acrylate resins, and the like. Various monomers such as methacrylates, acrylates, epoxies, and vinyls as raw materials may be added. In order to reduce the refractive index, it is preferable to add various fluorine-containing polymers or various fluorine-containing monomers to the first composition. The fluorine-containing polymer at this time is preferably a polymer obtained by polymerizing a fluorine-containing vinyl monomer, and preferably has a functional group copolymerizable with other components.

  Moreover, the 1st and 2nd composition can be diluted and used for a solvent as needed. As the solvent, solvents such as water, alcohols, esters, ketones, ethers and aromatics can be used.

  Further, in addition to the above-mentioned components, the first and second compositions include a small amount of a curing catalyst, a surfactant, an antistatic agent, an ultraviolet absorber, an antioxidant, a hindered amine and a hint as necessary. Light stabilizers such as dirt phenol, disperse dyes, oil-soluble dyes, fluorescent dyes, pigments and the like may be added. There is a possibility that the coating property can be improved and the coating performance after curing can be improved. As a method for forming the layer made of the first composition and the layer made of the second composition, a wet method can be used. Specifically, known methods such as a dipping method (immersion method), a spinner method, a spray method, and a flow method can be used.

  Hereinafter, an embodiment of the optical article of the present invention will be described. An optical article according to an embodiment of the present invention is a plastic lens for spectacles having a plastic substrate. The plastic lens of this embodiment is formed on a plastic lens substrate, a primer layer formed on the surface of the plastic lens substrate, a hard coat layer formed on the upper surface of the primer layer, and an upper surface of the hard coat layer. And a hollow silica fine particle-containing layer (organic antireflection layer), a hollow silica fine particle-free single layer (reinforcing layer), and an antifouling layer. In this example, the primer layer and the hard coat layer are base layers.

<Example 1>
First, preparation of the composition for forming each layer is demonstrated.

(C1) Preparation of primer layer forming composition A coating liquid (primer layer forming composition, primer layer forming coating liquid) PC1 for forming a primer layer by coating was prepared. First, 3700 parts by weight of methyl alcohol, 250 parts by weight of water, and 1000 parts by weight of propylene glycol monomethyl ether are charged into a stainless steel container, and after sufficiently stirring, composite fine particles mainly composed of titanium oxide, zirconium oxide, and silicon oxide. Sol (rutile type crystal structure, methanol dispersion, total solid concentration 20% by weight, manufactured by Catalyst Kasei Kogyo Co., Ltd., trade name "OPTRAIQUE 1120Z 8RU-25 / A1
7 ") 2800 parts by weight were added and mixed with stirring. Next, 2200 parts by weight of a polyurethane resin was added and stirred and mixed, and then 2 parts by weight of a silicone surfactant (manufactured by Nippon Unicar Co., Ltd., trade name “L-7604”) was added and stirring was continued for a whole day and night. Filtration was performed using a filter of No. 1 to obtain a primer layer forming composition PC1.

(C2) Preparation of hard coat layer forming composition A coating liquid (hard coat layer forming composition, hard coat layer forming coating liquid) HC1 for forming a hard coat layer by coating was prepared. First, in a stainless steel container, 1000 parts by weight of butyl cellosolve was taken, 1200 parts by weight of γ-glycidoxypropyltrimethoxysilane was added and stirred sufficiently, and then 300 parts by weight of 0.1 mol / liter hydrochloric acid was added, Stirring was continued all day and night to obtain a silane hydrolyzate. In this silane hydrolyzate, 30 parts by weight of a silicone surfactant (trade name “L-7001” manufactured by Nippon Unicar Co., Ltd.) was added and stirred for 1 hour, and then titanium oxide, tin oxide and silicon oxide were added. 7300 parts by weight of a composite fine particle sol (rutile type crystal structure, methanol dispersion, manufactured by Catalyst Kasei Kogyo Co., Ltd., trade name “OPTRAIQUE 1120Z 8RU-25, A17”) as a main component was added and mixed with stirring for 2 hours. Next, 250 parts by weight of epoxy resin (manufactured by Nagase ChemteX Corporation, trade name “Denacol EX-313”) was added and stirred for 2 hours, and then 20 parts by weight of iron (III) acetylacetonate was added and stirred for 1 hour. And it filtered with a 2 micrometers filter, and obtained composition HC1 for hard-coat layer formation.

(C3) Preparation of first composition (composition for forming an organic antireflection layer) for forming a layer (antireflection layer) comprising the first composition To form an organic antireflection layer by coating A coating liquid (coating liquid, first composition) AR1 was prepared. First, 0.3 g of 0.05N aqueous hydrochloric acid was added dropwise to 1.3 g of γ-glycidoxypropyltrimethoxysilane, which is one of the organosilicon compounds represented by R ³ R ⁴ _m SiX ² _3-m , with stirring. The mixture was further stirred for 4 hours and then aged overnight. In this solution, 7.0 g of hollow silica sol (manufactured by Catalyst Chemical Industry Co., Ltd., solid content concentration 10% by weight), 91.1 g of butyl cellosolve, 0.01 g of tris (2,4-pentanedionate) iron (III) and silicone 0.03 g of a system surfactant (manufactured by Nippon Unicar Co., Ltd., trade name “L-7001”) was added. After further stirring for 4 hours, the mixture was aged for a whole day and night to obtain a coating liquid AR1 for forming an organic antireflection layer. In the first composition AR1 for forming the organic antireflection layer, the content of hollow silica is 70% by weight in terms of solid content.

(C4) Preparation of second composition (reinforcing layer forming composition) for forming a layer (reinforcing layer) comprising the second composition Coating liquid (coating liquid, Second composition) RF1 was prepared. First, 0.4 g of γ-glycidoxypropyltrimethoxysilane, which is a non-fluorine tetrafunctional organosilicon compound represented by R ¹ R ² _n SiX ¹ _3-n , and 3.0 g of tetramethoxysilane, A 1.8N aqueous solution of 0.05N hydrochloric acid was added dropwise with stirring, and the mixture was further stirred for 4 hours and then aged overnight. In this liquid, 94.7 g of butyl cellosolve, 0.01 g of tris (2,4-pentandionate) iron (III), and 0.03 g of a silicone-based surfactant (trade name “L-7001” manufactured by Nihon Unicar Co., Ltd.) And were added. The mixture was further stirred for 4 hours and then aged for 24 hours to obtain a second composition RF1 for forming a reinforcing layer.

  Next, a process for producing a plastic lens using these compositions will be described.

(P1) Formation of primer layer A thiourethane plastic lens base material (manufactured by Seiko Epson Corporation, trade name “Seiko Super Sovereign Fabric” refractive index 1.67) was prepared. The lens substrate is subjected to alkali treatment. Specifically, the lens substrate is immersed in a 2.0 N aqueous potassium hydroxide solution maintained at 50 ° C. for 5 minutes, washed with pure water, and then washed with 0.5 N sulfuric acid maintained at 25 ° C. for 1 minute. Immersion neutralized. Thereafter, pure water was washed, dried and allowed to cool. Then, it was immersed in the primer layer forming composition PC1 prepared in (C1), pulled up at a lifting speed of 30 cm / min, and baked at 80 ° C. for 20 minutes to form a primer layer on the surface of the lens substrate. The formed primer layer had a thickness of 0.5 μm and a refractive index of 1.67.

(P2) Formation of Hard Coat Layer The lens base material on which the primer layer has been formed is immersed in the hard coat layer forming composition HC1 prepared in (C2) and pulled up at a lifting speed of 30 cm / min at 80 ° C. Baked for 30 minutes. Then, it heated for 3 hours in oven set to 125 degreeC, and formed the hard-coat layer on the primer layer. The formed hard coat layer had a thickness of 2.5 μm and a refractive index of 1.67.

(P3) Formation of organic antireflection layer The lens substrate on which the primer layer and the hard coat layer are formed is immersed in the first composition AR1 for forming the organic antireflection layer prepared in (C3). Then, it was pulled up at a pulling rate of 15 cm / min and baked at 80 ° C. for 30 minutes. Then, the heating and hardening process for 120 minutes was further performed at 120 degreeC. In this way, an organic antireflection layer was formed on the hard coat layer. The formed organic antireflection layer had a thickness of 78 nm and a refractive index of 1.37.

(P4) Formation of Reinforcing Layer The surface of the lens substrate on which the primer layer, the hard coat layer, and the organic antireflection layer were formed was plasma treated to make the organic antireflection layer hydrophilic. The plasma-treated lens base material was dipped in the second composition RF1 for reinforcing layer formation prepared in (C4), pulled up at a lifting speed of 15 cm / min, and heated and cured at 80 ° C. for 30 minutes. . Then, the heating and hardening process for 120 minutes was further performed at 120 degreeC. In this way, a reinforcing layer was formed on the organic antireflection layer. The formed reinforcing layer had a thickness of 10 nm and a refractive index of 1.46.

(P5) Formation of antifouling layer A fluorine-containing silane compound (manufactured by Shin-Etsu Chemical Co., Ltd., trade name “KY-130”) was diluted in perfluorohexane to prepare a 0.2% solution, and an antifouling layer was formed. A dipping treatment solution (dipping treatment solution, water repellent treatment solution) was used. The lens substrate on which the primer layer, the hard coat layer, the organic antireflection layer, and the reinforcing layer were formed was dipped in a dipping treatment solution for forming an antifouling layer and pulled up at a lifting speed of 15 cm / min. Thereafter, as a solvent removal step, the lens substrate coated with the immersion treatment liquid for forming the antifouling layer was put into a heating furnace at a temperature of 60 ° C. and a relative humidity of 20%, and held for 10 minutes. Subsequently, as an annealing process, an antifouling layer was formed by putting it in a constant temperature and humidity chamber set at a temperature of 60 ° C. and a relative humidity of 60%, and holding it for 2 hours. Thus, a plastic lens for spectacles was obtained.

<Example 2>
Using the same lens substrate as in Example 1, a primer layer and a hard coat layer were formed by the same processes (P1) and (P2).

(P3) Formation of organic antireflection layer The lens base material on which the primer layer and the hard coat layer are formed is immersed in the same first composition AR1 for forming the organic antireflection layer as in Example 1, The film was pulled up at a pulling rate of 12 cm / min and fired at 80 ° C. for 30 minutes. Then, the heating and hardening process for 120 minutes was further performed at 120 degreeC. In this way, an organic antireflection layer was formed on the hard coat layer. The formed organic antireflection layer had a thickness of 66 nm and a refractive index of 1.37.

(P4) Formation of Reinforcing Layer A lens substrate that has been plasma-treated in the same manner as in Example 1 is immersed in the same second composition RF1 for reinforcing layer formation as in Example 1, and pulled up at a lifting speed of 20 cm / min. Then, it was heated and cured at 80 ° C. for 30 minutes. Then, the heating and hardening process for 120 minutes was further performed at 120 degreeC. In this way, a reinforcing layer was formed on the organic antireflection layer. The formed reinforcing layer had a thickness of 20 nm and a refractive index of 1.46.

  Otherwise, a plastic lens for spectacles was obtained in the same manner as in Example 1.

<Example 3>
Using the same lens substrate as in Example 1, a primer layer and a hard coat layer were formed by the same processes (P1) and (P2).

(P3) Formation of organic antireflection layer The lens base material on which the primer layer and the hard coat layer are formed is immersed in the same first composition AR1 for forming the organic antireflection layer as in Example 1, The film was pulled up at a pulling rate of 8 cm / min and baked at 80 ° C. for 30 minutes. Then, the heating and hardening process for 120 minutes was further performed at 120 degreeC. In this way, an organic antireflection layer was formed on the hard coat layer. The formed organic antireflection layer had a thickness of 53 nm and a refractive index of 1.37.

(P4) Formation of Reinforcing Layer A lens base material that has been plasma-treated in the same manner as in Example 1 is dipped in the same second composition RF1 for reinforcing layer formation as in Example 1 and pulled up at a lifting speed of 24 cm / min. Then, it was heated and cured at 80 ° C. for 30 minutes. Then, the heating and hardening process for 120 minutes was further performed at 120 degreeC. In this way, a reinforcing layer was formed on the organic antireflection layer. The formed reinforcing layer had a thickness of 30 nm and a refractive index of 1.46.

  Otherwise, a plastic lens for spectacles was obtained in the same manner as in Example 1.

<Example 4>
Using the same lens substrate as in Example 1, a primer layer and a hard coat layer were formed by the same processes (P1) and (P2).

(P3) Formation of organic antireflection layer The lens base material on which the primer layer and the hard coat layer are formed is immersed in the same first composition AR1 for forming the organic antireflection layer as in Example 1, The film was pulled up at a pulling rate of 5 cm / min and baked at 80 ° C. for 30 minutes. Then, the heating and hardening process for 120 minutes was further performed at 120 degreeC. In this way, an organic antireflection layer was formed on the hard coat layer. The formed organic antireflection layer had a thickness of 40 nm and a refractive index of 1.37.

(P4) Formation of Reinforcing Layer A lens base material that has been plasma-treated in the same manner as in Example 1 is dipped in the same second composition RF1 for reinforcing layer formation as in Example 1 and pulled up at a lifting speed of 30 cm / min. Then, it was heated and cured at 80 ° C. for 30 minutes. Then, the heating and hardening process for 120 minutes was further performed at 120 degreeC. In this way, a reinforcing layer was formed on the organic antireflection layer. The formed reinforcing layer had a thickness of 40 nm and a refractive index of 1.46.

  Otherwise, a plastic lens for spectacles was obtained in the same manner as in Example 1.

<Comparative Example 1>
Using the same lens substrate as in Example 1, a primer layer and a hard coat layer were formed by the same processes (P1) and (P2).

(P3) Formation of organic antireflection layer The lens base material on which the primer layer and the hard coat layer are formed is immersed in the same first composition AR1 for forming the organic antireflection layer as in Example 1, The film was pulled up at a pulling rate of 20 cm / min and fired at 80 ° C. for 30 minutes. Then, the heating and hardening process for 120 minutes was further performed at 120 degreeC. In this way, an organic antireflection layer was formed on the hard coat layer. The formed organic antireflection layer had a thickness of 90 nm and a refractive index of 1.37.

  Thereafter, the antifouling layer was formed in the same manner as in Example 1 without forming the reinforcing layer. Otherwise, a plastic lens for spectacles was obtained in the same manner as in Example 1.

<Evaluation>
The plastic lenses for glasses obtained in Examples 1 to 4 and Comparative Example 1 were evaluated for water resistance, water trace residue, alkali resistance, antireflection effect, and scratch resistance. The durability described in the present application indicates the above water resistance and alkali resistance, and the hardness indicates scratch resistance.

The water resistance was evaluated as follows. The plastic lens for spectacles obtained in each example and comparative example was immersed in pure water at 60 ° C. and left as it was for 1 day. The appearance of the lens taken out from water was evaluated according to the following criteria.
“◎”: no peeling occurs “◯”: peeling occurs less than 5 mm ² “△”: peeling occurs 5 mm ² or more “×”: peeling occurs throughout

The remaining water marks were evaluated as follows. Water drops were dropped on the surface of the obtained plastic lens for spectacles and left as it was for 20 minutes. Then, the water droplet was wiped off and it was confirmed visually whether there was a water droplet trace.
“◎”: Water trace is not visible “○”: Water trace appears very thin “×”: Water trace is clearly visible

The alkali resistance was evaluated as follows. A part of the plastic lens for spectacles obtained in each of the above Examples and Comparative Examples was immersed in an aqueous sodium hydroxide solution prepared to 0.1 N for 2 hours as a test piece. The test piece after immersion was washed well with water. Appearance evaluation after wiping off water was evaluated according to the following criteria.
“◎”: no peeling occurs “◯”: peeling occurs less than 5 mm ² “△”: peeling occurs 5 mm ² or more “×”: peeling occurs throughout

The antireflection effect was evaluated as follows. The surface reflectance of the plastic lens for spectacles obtained in each example and comparative example was measured with a spectrophotometer (manufactured by Hitachi, Ltd., U-3500), and one side of the visible light range (400 nm to 700 nm) Average reflectance was calculated. This single-sided average reflectance was evaluated by converting to the transmittance of the film alone by the calculation of (1-one-sided average reflectance) ² .
“◎”: Average transmittance is 98.0% or more. The anti-reflection effect is very large.
“◯”: The average transmittance is 97.7% or more. Great anti-reflection effect.
“Δ”: The average transmittance is 97.4% or more. There is an anti-reflection effect.
"X": Average transmittance is 97.0% or less. Less antireflection effect.

The scratch resistance was evaluated as follows. A weight of 1 kg was applied with Bonstar # 0000 steel wool (manufactured by Nippon Steel Wool Co., Ltd.), and the surface of the plastic lens for spectacles obtained in each of the examples and comparative examples was rubbed 10 times to obtain a scratched extent. Visual evaluation was made.
“◎”: 0 to 5 scratches in the above range “◯”: 6 to 10 scratches in the above range “Δ”: 11 to 20 scratches in the above range “×” ": There are countless scratches

<Evaluation results>
FIG. 1 summarizes the evaluation results (water resistance, water trace residue, alkali resistance, antireflection effect, scratch resistance) of the plastic lenses for glasses obtained in Examples 1 to 4 and Comparative Example 1 above. It is shown.

  The plastic lenses produced in Examples 1 to 4 gave good results in all of the water resistance test, water trace test, alkali resistance test, antireflection effect test, and scratch resistance test. In the plastic lens manufactured in Example 4, the thickness of the reinforcing layer is 40 nm, which is slightly larger than the plastic lens obtained in the other examples. For this reason, although the antireflection effect was slightly small, a sufficient antireflection effect was obtained. Further, good results were obtained in the water resistance test, the water mark remaining test, the alkali resistance test, and the scratch resistance test. Therefore, considering the antireflection effect, the thickness d of the reinforcing layer is desirably 30 nm or less.

  On the other hand, since the plastic lens manufactured in Comparative Example 1 did not form a reinforcing layer, the water mark remaining test and the alkali resistance test result were not good. Moreover, the water resistance and scratch resistance test results were also inferior to the plastic lenses manufactured in Examples 1 to 4. Accordingly, it has been found that providing the reinforcing layer is very effective in improving the durability and hardness of the plastic lens as the optical article. In order to obtain such mechanical performance and to ensure a substantially uniform film thickness by the dipping method (dipping), the thickness d of the reinforcing layer is desirably 10 nm or more.

When manufacturing the spectacle lens of each of the above examples, the second composition for forming the reinforcing layer is a non-fluorine-based tetrafunctional group represented by R ¹ R ² _n SiX ¹ _3-n . Tetramethoxysilane is mainly contained as the organosilicon compound. And it turned out that the spectacle lens which has a reinforcement layer formed with this 2nd composition can obtain high durability and hardness as mentioned above. Therefore, it can be said that tetramethoxysilane is one of the preferred tetrafunctional organosilicon compounds contained in the second composition.

  In the above description, the base material is a plastic lens, but the same effect can be obtained even if the base material is a glass lens. An optical article having an antireflection function and having an organic layer formed on a base material or a base layer is not limited to a spectacle lens, but a wide variety of lenses for cameras, etc., and elements of an optical system of an image display device , Prisms, optical fibers, elements for information recording media, filters, DVDs, and other recording media, and glass for windows.

The figure which shows the evaluation result of an Example and a comparative example.

Claims (4)

It is formed on the base material directly or through at least one base layer, has a refractive index lower than that of the base material or the base layer, and has a refractive index difference of at least 0.1 relative to the base material or the base layer. An organic layer comprising a first composition comprising hollow silica fine particles having internal cavities and an organosilicon compound;
A second organic composition layer comprising a non-fluorine-based tetrafunctional organosilicon compound represented by the following general formula, which is a single layer organic layer formed on the surface of the first composition layer An optical article having a layer comprising:
R ¹ R ² _n SiX ¹ _3-n
In the formula, R ¹ is an organic group having a polymerizable reactive group, R ² is a hydrocarbon group having 1 to 6 carbon atoms, X ¹ is a hydrolytic group, and n is 0 or 1. is there. 2. The optical article according to claim 1, wherein the film thickness d of the layer made of the second composition satisfies the following condition.
10 nm ≦ d ≦ 30 nm   3. The optical article according to claim 1, wherein the layer made of the first composition contains 20 to 90% by weight of hollow silica fine particles.   4. The optical article according to claim 1, wherein the second composition contains tetramethoxysilane. 5.

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