JPH06138301A - Optical element - Google Patents

Abstract

PURPOSE:To provide the optical element which has a hard coat and an inorg. antireflection film and has excellent weatherability and consists of an org. glass base material having a primer layer of not generating light interference in spite of a high refractive index between org. glass and the hard coat. CONSTITUTION:This optical element is constituted by laminating a cured coating film of silicone and the inorg. antireflection film on the surface of the org. glass. The primer layer formed of a coating material consisting essentially of a reaction product obtd. by adding organoalkoxysilane to a two-pack type urethane resin coating material and hydrolyzing this organoalkoxysilane and inorg. particulates as essential components is interposed between the org. glass and the cured coating film of the silicone.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an organic glass surface,
The present invention relates to an optical element in which a silicone cured coating film (hard coat) and an inorganic antireflection film are laminated.

Here, the optical element means a lens, a cover for lighting equipment, a reflecting mirror, which is manufactured based on organic glass.
It is a concept that includes a prism, a filter, and the like.

The following description will be made by taking a spectacle lens as an example, but the present invention is not limited to this.

[0004]

2. Description of the Related Art In recent years, as a material for spectacle lenses, organic glass, which is lighter and less fragile than inorganic glass, has become widespread. However, in general, organic glass has markedly lower scratch resistance than inorganic glass.

Therefore, the surface of the lens usually has a silicone-based cured coating film (hereinafter referred to as "hard coat"). In addition, in the case of spectacle lenses, an inorganic antireflection film formed by dry plating such as vapor deposition of an inorganic substance has come to be provided on the lens for aesthetic reasons.

However, the lens having both the hard coat and the inorganic antireflection film on the organic glass substrate as described above has a problem that the impact resistance is poor.

Therefore, in order to improve the impact resistance of the hard coat, a technical idea of interposing a primer layer made of a urethane resin-based paint between the base material and the hard coat is disclosed (JP-A-63-63). 87223 ・ 63-141
001, JP-A-3-109502, etc.).

On the other hand, in recent years, an organic glass-based material is an aliphatic allyl carbonate type (CR-39, refractive index 1.5).
0) is being replaced by higher-refractive aromatic allyl carbonate type (refractive index 1.57), polythiourethane type (refractive index 1.60 to 1.70) and the like. In this case, the refractive index of the hard coat also prevents interference from light,
It should have the same refractive index as the base material.

[0009]

However, the refractive index of the primer layer made of the above urethane-based paint is 1.
Since it is around 50, light interference is inevitable even if the refractive index of the hard coat is made close to that of the base material. Further, in general, the urethane coating film is inferior in weather resistance even if it is a non-yellowing type, which is not desirable in the case of a spectacle lens which is often used outdoors.

In view of the above, an object of the present invention is to provide an optical element having a hard coat and an antireflection film, which has excellent weather resistance and causes optical interference even when the organic glass substrate has a high refractive index. It is to provide an optical element having a primer layer which is not allowed to be present between the organic glass and the hard coat.

[0011]

The inventors of the present invention have made extensive efforts to solve the above problems, and as a result, have completed the present invention having the following constitution.

In an optical element in which a hard coat and a single-layer or multi-layer inorganic antireflection film are laminated on the surface of an organic glass, the following components are essential active ingredients between the organic glass and the hard coat. An optical element having a primer layer formed of a paint interposed.

(A) A reaction product obtained by adding an organoalkoxysilane to a two-component urethane resin coating material and hydrolyzing the organoalkoxysilane.

(B) Inorganic fine particles

[0015]

Detailed Description of Means Each means of the present invention will be described in detail below. In the following description, the mixing unit is a weight unit unless otherwise specified.

A. The optical element of the present invention is premised on that a hard coat and an inorganic antireflection film are laminated on the surface of organic glass.

(1) The organic glass substrate is not particularly limited as long as it is transparent and has a refractive index of 1.40 to 1.70. Examples of the base material include polymethyl methacrylate, polycarbonate, aliphatic allyl carbonate-based, aromatic allyl carbonate-based, and polythiourethane.

(2) The hard coat (silicone-based cured coating film) is not particularly limited as long as it is of a silicone type. For example, a catalyst and metal oxide fine particles / composite fine particles are added to a hydrolyzate of an organoalkoxysilane, and a hard coat solution is prepared so that the viscosity can be appropriately applied with a diluting solvent. Further, agents such as an interfacial slip agent (leveling agent) and an ultraviolet absorber can be added to the hard coat liquid. The hard coat solution thus prepared is applied to a substrate by a conventional means and dried and cured to obtain a hard coat. The thickness of this hard coat is usually
It is 0.5 to 20 μm.

As the above-mentioned organoalkoxysilane, specifically, those represented by the general formula can be used.

R ¹ _a R ² _b Si (OR ³ ) _{4- (a + b)} (wherein R ¹ is an alkyl group having 1 to 6 carbon atoms, a vinyl group, an epoxy group, a methacryloxy group or a phenyl group, R
² is an alkyl group having 1 to 6 carbon atoms, a halogenated alkyl group, R ³ is an alkyl group having 1 to 4 carbon atoms, an alkoxyalkyl group, and a and b are 0, 1, 2 , A + b = 1, 2, or 3. ), More specifically, methyltrimethoxysilane, glycidoxymethyltrimethoxysilane, α-gilicidoxyethyltrimethoxysilane, β-glycidoxyethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane. Etc. can be mentioned. These may be used alone or in combination of two or more.

Examples of the catalyst include organic carboxylic acids such as trimellitic acid and trimellitic anhydride, titanium alkoxides, zirco alkoxides, silica alkoxides,
And the like, nitrogen-containing organic compounds such as methyl imidazole and dicyandiamide, metal complexes such as acetylacetone aluminum, and alkali metal organic carboxylates such as sodium acetate and potassium acetate.

As the above-mentioned diluent solvent, alcohols,
Of ketones, esters, ethers, and cellosolves (monoalkyl ethers of ethylene glycol), 1
It is possible to use one kind or a mixture of two or more kinds.

The metal oxides are mainly silicon oxide, iron (III) oxide, titanium (IV) oxide, cerium (IV) oxide, tin (IV) oxide, tungsten (VI) oxide, tantalum (V) oxide. , Antimony (III) oxide, zirconium oxide, aluminum oxide and the like can be used. In addition to the single use, two or more kinds may be used in combination, or may be used as composite fine particles.

This metal oxide hydrolyzate 100
The compounding amount with respect to parts is 0.2 to 5 parts. The particle size is 1 to 100 nm.

The above-mentioned coating method includes brush coating and
Immersion coating, roller coating, spray coating, spin coating, etc. can be mentioned. The conditions for dry curing are, for example, 80 to 120 ° C. × 2 hours.

(3) The antireflection film is formed by using an inorganic powder such as a metal, a metal oxide or a metal fluoride by a dry plating method such as vacuum deposition, sputtering or ion plating.

Examples of the above oxides include silicon dioxide, titanium (IV) oxide, tantalum (V) oxide, and antimony (III) oxide.
, Zirconium oxide, aluminum oxide and the like, and metal fluorides include magnesium fluoride and the like.

B. A primer layer made of urethane resin paint is interposed between the organic glass substrate of the present invention and the hard coat.

The above-mentioned primer coating must have each component of (1) a reaction product obtained by adding organoalkoxysilane to a two-pack type urethane resin coating and hydrolyzing the organoalkoxysilane, and (2) inorganic fine particles. It is the active ingredient. Then, if necessary, a leveling agent, an ultraviolet absorber and an antioxidant are added.

(1) The reaction product obtained by hydrolyzing the organoalkoxysilane with the two-component urethane resin coating added is prepared, for example, as follows.

Prepared by adding a hydrolysis catalyst, water, and a polar solvent to a polyol component, a polyisocyanate component, and a urethane resin catalyst, which are the components of the two-component urethane resin coating, and refluxing for 3 to 5 hours. To do.

(A) The above-mentioned two-pack type urethane resin coating material is a polyol-curing type coating material comprising a so-called polyol component and an isocyanate component. At this time, the ratio of both components is usually NCO / OH = 0.65 to 1.35, and preferably, 0.
75 to 1.1 If it is out of the range, the impact resistance of the primer layer is poor.

The long-chain polyol which is the main component of the above-mentioned polyol component is not particularly limited, such as polyether polyol, polyester polyol, acrylic polyol, epoxy polyol, etc., but from the viewpoint of impact resistance and the like,
The following polyether type is preferable.

Polyester polyols obtained by reacting a dicarboxylic acid such as succinic acid, glutaric acid, adipic acid or piperic acid with a diol component such as ethylene glycol, polyoxyethylene glycol, dipropylene glycol or polyoxypropylene glycol in excess. .

The above-mentioned isocyanate component may be any of yellowing, non-yellowing, etc.
Desirable from the viewpoint of weather resistance.

Hexamethylene diisocyanate (HMD) is included in addition to alicyclic isocyanates in addition to the aliphatic isocyanates that are non-yellowing isocyanates.
I), xylene diisocyanate (XDI), hydrogenated xylene diisocyanate (hydrogenated XDI), 4,4'-methylenebisdicyclohexyl diisocyanate (H12M)
DI), methylcyclohexyl diisocyanate (hydrogenated TDI), and isophorone diisocyanate (IPD)
I), etc., and from the viewpoint of handling, dimers, trimers, trimethylolpropane adducts, prepolymers and the like obtained by polymerizing them can be mentioned.

As the urethane resin catalyst, various amines, organic tin compounds, organic zinc compounds and the like can be used.

(B) The above-mentioned organoalkoxysilane is presumed to have a function of ensuring adhesion with the hard coat. The compounding amount of the component with respect to 100 parts of the urethane resin coating film component is usually 1 to 10 parts, preferably 3 to.
7 copies. If it is less than 1 part, the effect of addition of this component (securing the adhesiveness with the hard coat) is difficult to be exhibited, and if it exceeds 10 parts, the effect of improving impact resistance may be impaired. As the organoalkoxysilane, those exemplified in the above description of the silane-based cured coating film can be used.

(C) Hydrochloric acid is usually used as the catalyst for hydrolysis, and for example, it is added together with water in the form of a 10 ^-2 N aqueous solution of hydrochloric acid. As a polar solvent, methyl ethyl ketone (ME) is used.
K), acetone, acetylacetone, etc. can be preferably used.

(2) It is presumed that the above-mentioned inorganic fine particles have the functions of adjusting the refractive index and improving the weather resistance. The particle size of the inorganic part particles is usually 1 to 100 nm, preferably 10 to 50 nm.
nm. If it is less than 10 nm, it is difficult to expect improvement in the refractive index of the coating film, and if it exceeds 50 nm, the coating film tends to diffusely reflect,
Cloudy phenomenon is likely to occur. And, the inorganic fine particles are usually
It is desirable to use it in the form of an alcohol-dispersed sol.

The blending amount of the inorganic fine particles varies depending on the type of salt and oxide and the required refractive index, but is usually 10 to 10 with respect to 100 parts of the coating film component (urethane resin).
Set to 0. If it is less than 10 parts, the effect of adding inorganic fine particles (increasing the refractive index) is difficult to be achieved. If it exceeds 100 parts, the coating film tends to become cloudy.

The above-mentioned inorganic fine particles can be appropriately selected and used as single or composite fine particles from the metal oxides exemplified in the above description of the silane-based cured coating film. In addition, nitrides such as boron nitride, aluminum nitride, and silicon nitride, and boride, sulfide, fluoride, metal salt, and the like can be appropriately selected and used.

(3) A primer coating material prepared by adding the above inorganic fine particles to the above hydrolysis reaction product and stirring is applied onto the above organic glass substrate to obtain the optical element of the present invention.

The film thickness of this primer layer is 0.01 to 5
It is 0 μm. If it is 0.01 μm or less, the effect of impact resistance cannot be expected so much, and if it is 50 μm or more, surface accuracy (leveling property) is deteriorated. The refractive index of the primer layer depends on the kind and amount of the inorganic fine particles, but is 1.40 to 1.
70.

The coating method is selected from known methods such as a dipping method and a spin coating method. The curing condition is in the range of 80 ° C to 120 ° C for 1 minute to 60 minutes.

[0046]

In the optical element (plastic lens) of the present invention, the primer layer having the above-described structure is interposed between the hard coat and the organic glass, so that the optical layer has a resistance equal to or higher than the conventional one. Not only can the impact resistance be imparted to the optical element having the antireflection film formed on the hard coat, but the refractive index of the primer layer can be freely adjusted within the range of 1.40 to 1.70. Can also be applied. Further, weather resistance is also improved as compared with conventional primer layers made of urethane resin.

[0047]

EXAMPLES In order to confirm the effects of the present invention, examples carried out together with comparative examples will be described below.

A. Preparation of Primer Paint The paints of Examples and Comparative Examples were prepared by adding the indicated inorganic fine particles to the reaction product obtained by reacting the composition (excluding the inorganic fine particles) having the formulation shown in Table 1 for 4 hours under reflux. To prepare each primer coating.

Specific examples of each component used in each example and comparative example are as follows.

Polyisocyanate ... "Coronate H
X "Nippon Urethane Resin Co., Ltd., non-yellowing adduct polymer (HMDI type), NCO content 20% Polyester polyol I ..." Nipporan 192 "
Made by Nippon Urethane Resin Co., Ltd., OH value: 107 KOH
mg / g, solid content concentration: 80% Polyester polyol II ... "Nipporan 131" made by Nippon Urethane Resin Co., Ltd., OH value: 147 KOH m
g / g, solid content concentration: 100% Inorganic fine particles ... The composition ratio of the composite oxide is a sol in which the indicated oxide having a particle size of 30 nm is dispersed in methanol at a solid content of 30%, and Fe ₂ O ₃ / TiO ₂ is used. ₂ = 2/98, C
eO ₂ / TiO ₂ = 20/80 B.I. Preparation of hard coat liquid <Hard coat liquid a> 100 parts of γ-glycidoxypropyltrimethoxysilane, 200 parts of MeoH, 10 ^-2 NH
After hydrolyzing 100 parts of Cl at reflux for 2 hours, 1200 parts of methanol silica sol, 7 parts of acetylacetone aluminum, and 0.4 part of "Fc430" (a fluorine-based interfacial lubricant manufactured by Sumitomo 3M, the same applies hereinafter) are added.

<Hard coat liquid b> γ-glycidoxyp
100 parts of ropyltrimethoxysilane, 15 parts of ethyl silicate
Parts, methanol 20 parts, 10^-2Mix 25 parts of N HCl
And hydrolyzed at room temperature for 24 hours, Fe₂ O₃ / TiO
₂ Alcoholic sol of complex (Fe₂ O₃ / TiO ₂ =
2/98, average particle size 30 nm, solid content concentration 30%) 10
0 part, acetylacetone aluminum 20 parts, "FC-
430 "4 parts were mixed.

<Hard Coat Solution c> In the hard coat solution b, SnO ₂ alcoholic sol (average particle size: 30) was used instead of the alcoholic sol of the Fe ₂ O ₃ / TiO ₂ composite.
nm, solid content concentration 30%).

<Hard coating solution d> 100 parts of γ-glycidoxypropyltrimethoxysilane, 15 parts of ethyl silicate
Parts, 20 parts of methanol and 25 parts of 10 ^-2 NHcl are mixed and hydrolyzed at room temperature for 24 hours, and WO ₃ alcoholic sol (average particle size 30 nm, solid content concentration 30%) 150
Part, 20 parts acetylacetone aluminum, "FC-4
30 "4 parts were mixed.

<Hard Coat Solution e> In the hard coat solution d, Sb ₂ O ₃ alcoholic sol (average particle size 30 nm, solid content concentration 30%) is used instead of WO ₃ sol.

C. Preparation of Test Piece (1) Formation of Primer Layer The base material shown in Table 1 was coated with the primer coating material of each of the examples shown by the dipping method (pulling speed 100 mm / sec), and the conditions were 100 ° C. × 10 minutes. Cured. The specifications of the base material used are as follows. In addition, the test piece 12 did not form a primer coating film.

CR-39: Polyglycol bisallyl carbonate lens, refractive index 1.50 1.57 lens: diallyl isophthalate / allyl benzoate / benzyl methacrylate copolymer, refractive index 1.5
7 1.6 lens: diallyl diphenate / urethane acrylate / diisopropyl peroxydicarbonate copolymer, refractive index 1.6 1.66 lens: polythiourethane lens, refractive index 1.66 (2) formation of hard coat On the base material on which the primer coating film has been formed, the hard coat liquid shown is applied by a dipping method (pulling speed 100 mm /
sec) and then cured at 100 ° C. × 2 hours or 110 ° C. × 2 hours.

(3) Formation of Antireflection Film On the base material on which the above hard coat is formed, a vapor deposition film is formed by vacuum vapor deposition with an inorganic substance having the following constitution.

SiO ₂ / ZrO ₂ : 1/4 λ, ZrO ₂ :
1/4 λ, SiO ₂ : 1/4 λ D. Test Items Each test item prepared as described above was subjected to the tests of the following items.

(1) Adhesion test between primer layer and silicone-based cured coating film A test piece before forming an antireflection film was formed into 100 squares at 1 mm intervals in a 1 cm square, and an adhesive tape made of cellophane was used. After pressing strongly, the film was rapidly peeled in the 90 ° direction, and the number of squares that did not peel was counted.

(2) Scratch resistance test A 600 g load of steel wool (# 0000) was applied to the surface of the antireflection film of each test piece to rub it 30 times, and the degree of scratching was judged according to the following criteria. Did.

○ The scratched area is within 10%.

△ The scratched area is more than 10% and less than 30%. Χ The area with scratches exceeds 30%.

(3) Impact resistance test A steel ball was dropped from a height of 127 cm to the center of the test piece and judged by how many grams it did not crack (withstand).

(4) Appearance Fluorescent lamp (tri-wavelength medium white) "Product name: Lupica Ace 15W Mitsubishi Electric Co., Ltd." is placed in the blackened background.
The light of a fluorescent lamp was reflected on the surface of the antireflection film of the test piece, and the presence or absence of the light interference color (rainbow pattern) formed on the surface of the object was judged.

(5) Weather resistance test Accelerated weather resistance test (Suga Shinken Co., Ltd. "Sign Shine Super Long Life Weather Ometer") 200h
After exposure, the presence or absence of the above-mentioned appearance was visually judged.

E. Test Results and Evaluation From Table 1 showing the test results, it can be seen that each example of the present invention is good in all items. On the other hand, in the case of the test piece 4 using the primer (Comparative Example 1) containing no inorganic fine particles, it can be seen that interference fringes do not appear in the appearance, but the weather resistance is poor. In addition, in the case of the test piece 5 using the primer (Comparative Example 2) containing no organoalkoxysilane, it can be seen that the adhesion between the hard coat and the substrate is poor. Further, it can be seen that the test piece 13 having no primer coating is inferior in impact resistance.

[0067]

[Table 1]

[0068]

[Table 2]

Claims (4)

[Claims] 1. An optical element in which a silicone cured coating film and an inorganic antireflection coating are laminated on the surface of an organic glass, wherein the following components are essential active ingredients between the organic glass and the silicone cured coating film. An optical element having a primer layer formed of a paint interposed. (a) A reaction product obtained by adding an organoalkoxysilane to a two-component urethane resin coating material and hydrolyzing the organoalkoxysilane, (b) inorganic fine particles. 2. The optical element according to claim 1, wherein the inorganic fine particles are added as a metal oxide in the form of an alcoholic sol. 3. A primer coating for forming a primer layer between an organic glass and a silicone cured coating film, wherein the following components are essential active ingredients. (a) A reaction product obtained by hydrolyzing an organoalkoxysilane in a state of containing a two-component urethane resin coating material, (b) inorganic fine particles. 4. The primer coating composition according to claim 3, wherein the inorganic fine particles are metal oxides added in the form of an alcoholic sol.