JP2590787B2 - Optical components with coating - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plastic optical component, and more particularly to a spectacle lens made of plastic.

[0002]

2. Description of the Related Art Plastic moldings are used in large quantities, taking advantage of their advantages such as light weight, easy processability and impact resistance, but on the other hand, they have insufficient hardness, are easily damaged, and are easily attacked by solvents. However, they have drawbacks such as being charged and adsorb dust, and having insufficient heat resistance, and have been practically unsatisfactory for use as spectacle lenses and window materials as compared with inorganic glass molded products.

[0003] Therefore, it has been proposed to apply a protective coat to a plastic molded product. Numerous types of coating compositions for use in coatings have been proposed. Among them, a “coating composition containing an organosilicon compound or a hydrolyzate thereof as a main component (a resin component or a coating film forming component), which is expected to give a hard coating film close to an inorganic system”
(See, for example, JP-A-52-11261),
It is practically used for eyeglass lenses.

[0004] However, this coating composition is still unsatisfactory in abrasion resistance (scratch resistance), and a composition in which a silica sol dispersed in a colloidal form is added thereto has been proposed (for example, JP-A-53-111336). See also
It is practically used for eyeglass lenses. Conventionally, almost 100% of plastic glasses lenses have been manufactured by casting polymerization of a monomer called diethylene glycol biscarbonate (commonly called CR-39).
This lens has a refractive index of about 1.50, which is lower than the refractive index of a glass lens of about 1.52. Had become.

[0005] For this reason, the development of monomers higher than CR-39 has been promoted, for example, as described in JP-A-55-13747 and JP-A-56-1.
No. 66214, JP-A-57-23611 and JP-A-57-54901 have been proposed. At present, several companies have commercialized plastic lenses having a medium to high refractive index of n _d = 1.54 to 1.60. These lenses are also coated with the coating composition containing the silica sol.

[0006]

However, plastic optical parts to which a coating composition containing silica sol is applied have a problem that interference fringes are visible on the coating film and the appearance is poor. In addition, in many lenses, an antireflection film (consisting of a multilayer structure film of an inorganic oxide thin film based on the theory of optical interference) is formed on a coating film. in this case,
Although the anti-reflection film exhibits, for example, an extremely light green reflection color,
This reflected color changes according to the position of the lens surface, and there is a problem that there is unevenness.

Accordingly, a first object of the present invention is to provide n _d = 1.
For 54 to 1.60 medium to high refractive index plastic molded products,
It is an object of the present invention to provide a plastic optical component coated with a coating composition that gives a coating film in which interference fringes are not visible in the coating film and the reflection color is not uneven. Further, the second aspect of the present invention
An object of the present invention is to provide a plastic optical component having excellent scratch resistance, surface hardness, abrasion resistance, flexibility, transparency, antistatic property, dyeability, heat resistance and the like.

[0008]

Means for Solving the Problems The present inventor has made the present invention for the purpose of solving the above problems.
The present invention provides a plastic optical component comprising a transparent plastic substrate having a refractive index of 1.54 or more, and a coating obtained by curing a coating composition containing the following components (a) and (b) as main components. .

(A) General formula: R ¹ _a R ² _b Si (OR ³ ) _{4- (a + b)} (formula I) (wherein, R ¹ represents a functional group or an unsaturated double bond) Is an organic group having 4 to 14 carbon atoms, R ² is a hydrocarbon group having 1 to 6 carbon atoms or a halogenated hydrocarbon group, and R ³ is an alkyl group or an alkoxyalkyl group having 1 to 4 carbon atoms. Or an acyl group, and a and b are each 0 or 1,
And a + b is 1 or 2. (B) a coating composition comprising a colloidally dispersed tungsten oxide sol

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION

Description of the component (a): Among the compounds of the general formula (I), when R ¹ has an epoxy group as a functional group, for example, the following compounds are used. (1) General formula (II)

[0011]

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(Wherein, R^FourIs a group having 1 to 4 carbon atoms.
Alkyl group or alkoxyalkyl group or acyl group, R^Five
Is a hydrocarbon group having 1 to 6 carbon atoms or a halogenated hydrocarbon
Group, R ⁶Is a hydrogen or methyl group, m is 2 or 3, p is
1-6 and q are 0-2. ). (2) General formula (III)

[0013]

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(Where R ⁷ is an alkyl group or alkoxyalkyl group or acyl group having 1 to 4 carbon atoms, R ⁵ is a hydrocarbon group or halogenated hydrocarbon group having 1 to 4 carbon atoms, l
Is 2 or 3, and r is 1-4. ). Since all of the compounds represented by the above general formula have an epoxy group, they are also called epoxysilane.

Specific examples of epoxysilane include, for example, γ-glycidoxypropyltrimethoxysilane, γ
-Glycidoxypropyltriethoxysilane, γ-glycidoxypropyltrimethoxyethoxysilane, γ-glycidoxypropyltriacetoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane , Β- (3,4-
Epoxycyclohexyl) ethyltriethoxysilane and the like.

Examples of the compounds of the general formula (I) other than those in which R ¹ has an epoxy group as a functional group (including those in which a = 0) include, for example, the following: . Methyltrimethoxysilane, methyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltriacetoxysilane, vinyltrimethoxyethoxysilane, γ-methacryloxypropyltrimethoxysilane, aminomethyltrimethoxysilane, 3
-Aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, γ-chloropropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, 3,3,3-tri Various trialkoxysilanes such as fluoropropyltrimethoxysilane, trisiloxysilane or trialkoxyalkoxysilane compounds.

All of the above-mentioned compounds of the general formula (I) have three OR ³ groups bonded to Si atoms (a +
b = 1) This is an example of trifunctionality, but there are two OR ³ groups (a +
b = 2) Bifunctional equivalents can of course also be used. Examples of bifunctional equivalent compounds include dimethyldimethoxysilane, diphenyldimethoxysilane, methylphenyldimethoxysilane, methylvinyldimethoxysilane, dimethyldiethoxysilane, and the like.

The compounds of the general formula (I) may be used alone or in combination of two or more according to the purpose. In particular, when a bifunctional compound is used, it is preferable to use it in combination with a trifunctional compound. When they are used together, 2> a + b> 1 on average. Furthermore, it is also possible to use a tetrafunctional equivalent compound of a + b = 0 in combination.
Examples of tetrafunctional equivalents include methyl silicate, ethyl silicate, isopropyl silicate, n-
Propyl silicate, n-butyl silicate, t-butyl silicate, sec-butyl silicate and the like can be mentioned.

The compound of the formula (I) may be used as it is, but is preferably used as a hydrolyzate for the purpose of increasing the reaction rate and lowering the curing temperature. When two or more compounds having the same functional number are used in combination of two or four functional compounds, or two or more compounds having different functional numbers are used in combination, they may be used together after hydrolysis, Co-hydrolysis may be carried out in combination before. Upon hydrolysis, the alcohol HOR ³ is liberated, and the compound of general formula (I) has the corresponding silanol:

[0020]

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## EQU1 ## Silanol rapidly undergoes dehydration condensation to become an oligomer. Therefore, after the hydrolysis, it may be left (cured) for 1 to 24 hours so that this reaction proceeds sufficiently. Description of the component (b): Tungsten oxide of a tungsten oxide sol dispersed in a colloidal form can be represented by W ₂ O ₅ to WO ₃ .

Such a sol itself is known and partially available as a commercial product. The particle size of the sol is 1 to 200
mμ, particularly preferably 5 to 100 μm. If it is smaller than this, the production is difficult and the stability of the sol itself is poor,
In addition, if the effect is small and larger than this, the stability of the coating composition, the transparency and smoothness of the coating film, etc. are reduced.

The sol is a colloidal solution obtained by dispersing tungsten oxide fine particles in water or an organic solvent or a mixed solvent of both, and is useful when stabilized by adding a suitable alkali, particularly an organic amine. (c) Description of the components: A curing catalyst is optionally added, and the curing catalyst may be used as needed to shorten the time required to polymerize the component (a) to form a three-dimensional network coating film. (However, those that impair the stability of the coating composition are not preferred). For example, the following are used.

(1) Amines: monoethanolamine, diethanolamine, isopropanolamine, ethylenediamine, isopropylamine, diisopropylamine, morpholine, triethanolamine, diaminopropane, aminoethylethanolamine, dicyandiamide, triethylenediamine, 2-ethyl-4 -Methylimidazole.

(2) Various metal complex compounds: General formula: AlX _n Y _3-n (where X is OL (L is a lower alkyl group), and Y is general formula M ¹ COCH ₂ COM ² (M ¹ , M ² is a lower alkyl group) and M ¹ COCH
_{2 At} least one selected from ligands derived from COOM ² ,
n is 0, 1 or 2).

Particularly useful chelate compounds include aluminum acetylacetonate, aluminum bisethylacetoacetate monoacetylacetonate, and aluminum di-n-ethyl acetate from the viewpoint of solubility, stability and catalytic effect.
-Butoxide-monoethylacetoacetate, aluminum-di-iso-propoxide monomethylacetoacetate and the like. In addition, chromium acetylacetonate, titanyl acetylacetonate, cobalt acetylacetonate, iron (III) acetylacetonate, manganese acetylacetonate, nickel acetylacetonate.

(3) Metal alkoxides: aluminum triethoxide, aluminum tri-n-propoxide, aluminum tri-n-butoxide, tetraethoxy titanium, tetra n-butoxy titanium, tetra i-propoxy titanium. (4) Organic metal salts: sodium acetate, zinc naphthenate, cobalt naphthenate, zinc octylate, tin octylate.

(5) Perchlorate: magnesium perchlorate,
Ammonium perchlorate. (6) Organic acid or anhydride thereof:
Malonic acid, succinic acid, tartaric acid, adipic acid, azelaic acid, maleic acid, O-phthalic acid, terephthalic acid, fumaric acid, itaconic acid, oxaloacetic acid, succinic anhydride, maleic anhydride, itaconic anhydride, 1,2- Dimethyl maleic anhydride, phthalic anhydride, hexahydrophthalic anhydride,
Naphthalic anhydride.

(7) Lewis acid: ferric chloride, aluminum chloride. (8) Metal halides: stannous chloride, varnish chloride, tin bromide, zinc chloride, zinc bromide, titanium tetrachloride, titanium bromide, thallium bromide, germanium chloride, hafnium chloride, lead chloride, bromide lead.

The above catalyst can be used without using
You may mix and use more than one kind. In particular, when the component (a) has an epoxy group, one that also functions as a ring-opening polymerization catalyst for the epoxy group may be used. In particular, an aluminum chelate compound is one of the preferred catalysts. (d) Description of components: A solvent is used as necessary to make the coating composition liquid or to lower the viscosity. For example, water, lower alcohol, acetone, ether, ketone, ester and the like are used. In the coating composition of the present invention, component (b) is used in an amount of 10 to 400 parts by weight (solid content), preferably 50 to 250 parts by weight (solid content), per 100 parts by weight (solid content) of component (a). , (A)
Per 100 parts by weight (solid content) of the component and component (b),
Suitably, component (c) is used in an amount of 0.00001 to 20 parts by weight. The component (d) is used in an appropriate amount depending on the viscosity of the composition.

In addition to the above components (a) to (d), if necessary, for example, for the purpose of improving adhesion to a substrate (molded product) on the side to be coated, improving weather resistance, or coating. Various additives may be used in combination for the purpose of improving the stability of the composition. Examples of additives include pH adjusters, viscosity improvers, leveling agents, matting agents, dyes, pigments, stabilizers,
There are ultraviolet absorbers, antioxidants and the like.

In addition, an epoxy resin or another organic polymer may be used in combination for the purpose of improving the dyeability of the coating film.
Epoxy resins include alicyclic epoxy resins such as polyolefin epoxy, cyclopentadiene oxide, cyclohexene oxide, or polyglycidyl ester, polyglycidyl ether, epoxidized vegetable oil, and novolak type, which are widely used for coatings and casting. There is an epoxy novolak composed of a phenol resin and epichlorohydrin, and furthermore, glycidyl methacrylate is a methyl methacrylate copolymer.

Other organic polymers include, for example,
Examples include polyols, cellulose resins, and melamine resins.
Various surfactants can be used in combination with the coating composition for the purpose of improving the flow at the time of application, improving the smoothness of the coating film and reducing the friction coefficient of the coating film surface, and in particular, dimethyl siloxane A block or graft copolymer of styrene and an alkylene oxide, and a fluorine-based surfactant are effective.

In some cases, inorganic fillers such as silica sol, antimony oxide sol, and diamond fine particles may be used in combination as long as the object of the present invention is not impaired. The compositions according to the invention are applied in particular to plastic moldings. Speaking of molded articles, for example, polymethyl methacrylate and its copolymer, acrylonitrile styrene copolymer, polycarbonate, cellulose acetate, polyvinyl chloride, polyethylene terephthalate, epoxy resin, unsaturated polyester resin, polyurethane resin, CR The composition of the present invention is applied to a polymer such as -39.

In terms of the shape of the molded product, a lump, a wire,
The composition of the present invention is applied to a film or the like. In terms of the function of the molded product, the composition of the present invention is applied to optical products, particularly camera lenses, spectacle lenses, reflectors, prisms and the like. The composition of the present invention is particularly useful as an anti-scratch film for “glass lenses” molded with a resin having a medium to high refractive index of n _d = 1.53 or more.

The composition of the present invention can be applied not only to plastic molded articles but also to inorganic glass, wood, metal articles and the like. As a coating means, a normal coating method such as brush coating, dipping, roll coating, spray coating, and flow coating can be used. Furthermore, after applying the composition of the present invention to a mold, the raw material to be a substrate molded product is cast and polymerized to form a plastic molded product, or after the composition of the present invention is applied to the molded product, it is still cured. An uncoated film surface can be brought into close contact with a mold, and the coating film can be cured thereon.

The coating composition according to the present invention comprises:
After the application, it is often cured by heat treatment to obtain a hard coating. A sufficient effect can be obtained at a heating temperature of about 50 to 200 ° C, preferably 80 to 140 ° C. In general, it is sufficient that the thickness of the coating film after drying is from 0.3 to 30 .mu., Preferably from 0.5 to 10 .mu.m.

The coating film is transparent and excellent in hardness, especially scratch resistance, and does not cause deterioration in appearance due to scratches, which is a problem of plastic molded products, and can provide molded products having extremely high commercial value. Hereinafter, the present invention will be described more specifically with reference to Examples, but the present invention is not limited thereto.

[0039]

【Example】

(1) Preparation of Preliminary Composition A: γ-glycidoxypropylmethyldiethoxysilane was placed in a reaction vessel equipped with a rotor.
A part by weight was charged, and 36 parts by weight of a 0.05 N hydrochloric acid aqueous solution was added at a time with vigorous stirring using a magnetic stirrer.

Immediately after the addition, the solution was a heterogeneous solution, but became a colorless and transparent solution while generating heat in a few minutes. Stirring was further continued for 1 hour to obtain a hydrolyzate corresponding to the component (a).
The obtained hydrolyzate was added with ethanol (56.6) as a component (d).
Parts by weight and 53.4 parts by weight of ethylene glycol, and then aluminum acetylacetonate as the component (c).
4.7 parts by weight were added and sufficiently mixed and dissolved to prepare Preparative Composition A. (2) Preparation of Preliminary Composition B: 212.4 parts by weight of γ-glycidoxypropyltrimethoxysilane was charged into a reaction vessel equipped with a rotor, the temperature in the vessel was kept at 10 ° C., and a magnetic stirrer was used. With vigorous stirring, 48.6 parts by weight of a 0.01 N hydrochloric acid aqueous solution was gradually added dropwise. Immediately after the completion of the dropping, the cooling is stopped.
A hydrolyzate corresponding to (a) was obtained. To the obtained hydrolyzate, after adding 77.1 parts by weight of ethanol and 37.7 parts by weight of ethylene glycol as the component (d), 7.65 parts by weight of aluminum acetylacetonate as the component (c) was added,
By sufficiently mixing and dissolving, Preparatory Composition B was prepared. (3) Preparation of coating composition:
Preliminary compositions A and B prepared in (1) and (2) were weighed and poured by weight (not solid content) shown in Table 1 below, and commercially available tungsten oxide sol (water-dispersed sol, Average particle size: 10 to 15 mμ, solid content 20%) 200 parts by weight (not solids) and silicone surfactant 0.45 parts by weight are added, and the mixture is sufficiently stirred and mixed to give a uniform, colorless and transparent solution. A coating composition was prepared. (4) Coating: A commercially available polycarbonate lens having a refractive index n _d = 1.59 was prepared and immersed in the lens (with a pulling speed of 10).
cm / min), and the coating composition was heated at 100 ° C. for 2 hours to cure the coating. (5) Evaluation: The lens with the cured coating film obtained in (4) was subjected to the following test to evaluate the performance of the coating film. (A) Friction resistance test The surface of the coating film was rubbed with steel wool # 0000, and the scratch resistance was examined. In addition, evaluation was performed as follows.

A: No damage is caused even by strong friction. …: Slightly scratched when rubbed quite strongly. ×: Scratches even with weak friction. Incidentally, the evaluation of the lens without the coating film was x. (B) Appearance A general-purpose anti-reflection film was formed on the coating film cured in the above section (4) by a vacuum deposition method, and the unevenness of the reflection color was visually observed, and evaluated as follows.

◎: No unevenness of reflected color ○: 〃 Slight X: 著 し い marked (c) Adhesion After immersing the lens having the cured coating film in hot water of 90 ° C. for 2 hours,
By making a cut line in the vertical and horizontal directions every 1 mm with a knife on the coating surface, 100 goban eyes are made,
Cellophane adhesive tape (trade name “Cellotape” manufactured by Nichiban Co., Ltd.) was strongly attached. With one end of the tape in hand, the tape was rapidly peeled off in the direction of 90 degrees, and the number of peeled goban eyes on the coating film was examined. The number X of the eyes of the peeled goban is expressed as X / 100 with the number being the numerator. The smaller the X, the better the adhesion. (D) Dyeability The lens having the cured coating film was immersed in a disperse dye (mixed three colors of red, yellow, and blue) bath at 90 ° C. for 30 minutes, and the degree of dyeing was measured by light transmittance.

The results of the above evaluation are shown in Table 1 below. [Comparative Example 1] In the same manner as in the Example, except that a commercially available silica sol (methanol-dispersed sol, average particle diameter: 13 ± 1 mμ, solid content: 20%) was used instead of the tungsten oxide sol. The coating composition of this example was prepared and evaluated. [Comparative Example 2] A commercially available antimony pentoxide sol (average particle diameter: 15
m.mu., solid content 20%), except that the coating composition of this example was prepared and evaluated in substantially the same manner as in the example.

The results of the above evaluation are shown in Table 1 below.

[0045]

[Table 1]

[0046]

As described above, according to the present invention, a plastic optical component having the following characteristics can be obtained. (1) When applied to a medium to high refractive index plastic spectacle lens to form a hard coating film and then form an antireflection film thereon, a plastic optical component with less unevenness of reflection color can be obtained.

(2) A plastic optical component having excellent scratch resistance, surface hardness, abrasion resistance, flexibility, transparency, heat resistance and the like of the coating film can be obtained. (3) The elongation of the coating film is large, the risk of cracks on the surface of the coating film is extremely small even if the substrate is bent, and the adhesion to a plastic substrate having a medium to high refractive index is good. (4) There is no trouble such as curling when applied to a thin film, in which the shrinkage during curing is small.

(5) A plastic optical component having excellent antistatic properties and antifouling properties can be obtained. (6) Since the coating film can be dyed with a disperse dye, colored and dyed optical components, particularly dyed and colored lenses, can be obtained. (7) A plastic optical component having a large surface reflectance of the coating film and a good antireflection effect can be obtained.

(8) A plastic optical component having a thin film with good adhesion to a coating film such as an antireflection film or a metal vapor-deposited film, and with less peeling can be obtained. (9) Since the sliding properties of the coating film surface are good (the coefficient of friction is low), a plastic optical component with improved scratch resistance can be obtained. that's all

Claims (2)

(57) [Claims] 1. A plastic, comprising a transparent plastic substrate having a refractive index of at least 1.54 and a film formed by curing a coating composition comprising the following components (a) and (b) as main components: Optical components. (a) General formula: R ¹ _a R ² _b Si (OR ³ ) _{4- (a + b)} (formula I) (wherein, R ¹ is a functional group or the number of carbon atoms having an unsaturated double bond) An organic group having 4 to 14 carbon atoms, R ² is a hydrocarbon group having 1 to 6 carbon atoms or a halogenated hydrocarbon group, and R ³ is an alkyl group having 1 to 4 carbon atoms, an alkoxyalkyl group or an acyl group. And a and b are each 0 or 1,
And a + b is 1 or 2. (B) a coating composition comprising a colloidally dispersed tungsten oxide sol 2. The tungsten oxide sol having a particle size of 1 to 2.
The optical component according to claim 1, wherein the optical component has a diameter of 200 mμ.