JPH02160543A - Double layer coating - Google Patents

Abstract

PURPOSE:To improve surface hardness, reflection preventive properties, durability, transparency, shock resistance and antistatic characteristic, by a method wherein a top and bottom coatings are applied to the surface of a base material and the bottom layer coating is obtained by a curing a composition containing silica sol, an organic silicide and/or its hydrolysate. CONSTITUTION:A double layer coating applied to the surface of a base material is constituted of a bottom layer coating and top layer coating having a thickness of 0.01-10mum. Then the bottom layer is obtained by curing a composition containing silica sol having mean particle diameter of 1-200mmu and an organic silicide displayed by formula R<2>aR<3>bSi(OR<4>)4-a-b and/or its hydrolysate. Provided that in the formula R2 and R3 are hydrocarbon group possessing respectively an alkyl group or an alkenyl group or an aryl group or a halogen group or an epoxy group or an amino group or a mercapto group or methacryloxy group or cyano group, R4 is 1-8C alkyl group or an aryl group or an alkoxy alkyl group or an acyl group (a) and (b) are respectively 0 or 1 and (a)+(b) is 1 or 2.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a coating formed on various substrates, which has particularly improved surface hardness, antireflection properties, transparency, durability, and impact resistance. It relates to multilayer coatings.

[Prior art] Regarding protection of various base materials, improvement of appearance quality, and imparting surface functions,
Methods of solving the problem by coating a substrate with various coating materials have been widely used, and various proposals have been made regarding the materials and coating methods.

On the other hand, such coating materials are charged with static electricity, which often causes inconvenience. For example, the ease with which it gets dirty due to the adhesion of dust,
Disturbing electric sparks caused by contact with human bodies in low humidity conditions can cause malfunctions in instruments, electronic equipment, etc., especially due to electrostatic charge.

These solutions and 1. Various proposals have been made so far. For example, antistatic substances such as surfactants are added to the coating material or applied to the coating material, but the antistatic properties of these substances are temporary, and if they are added to the coating material, they may affect the water resistance of the coating material. There are negative effects such as deterioration. There are other proposals for high hardness coatings with antistatic properties (Japanese Patent Application Laid-Open No. 109084/1984), but these are based on a balance with other properties in order to primarily impart antistatic properties to the outermost layer. is difficult.

Further, a hard coat composition containing silica sol as a coating component is also disclosed in Japanese Patent Application Laid-Open No. 111336/1983. However, this did not provide sufficient antireflection properties.

[Problems to be Solved by the Invention] The purpose of the present invention is to enable a wide range of selection of coatings having various surface properties, with particular excellence in surface hardness, antireflection, durability, transparency, impact resistance, etc. More preferably, the present invention aims to provide a multilayer coating having excellent antistatic properties.

[Means for Solving the Problems] In the present invention, the lower layer film is obtained by curing a composition containing the following component A, and the upper layer film has a thickness of 0.01.
Its structure is a multilayer coating characterized by a coating of μm to 10 μm.

A, silica sol with an average particle diameter of 1 to 200 mμ.

and.

General formula R2R3bS i (OR')4-i-b4
-Organosilicon compounds and/or hydrolysates thereof.

Here, R2 and R3 are each an alkyl group, an alkenyl group, an allyl group, or a hydrocarbon group having a halogen group, an epoxy group, an amino group, a mercapto group, a methacryloxy group or a cyano group, and R4 is a carbon group having 1 to 8 carbon atoms. It is an alkyl group, allyl group, alkoxyalkyl group, or acyl group, a and b are 0 or 1, and a+b is 1 or 2.

Here, the average particle diameter 1 indicated as component A in the present invention
Silica sol of ~200 mμ is manufactured by a well-known method and is commercially available, and it is necessary to use silica with an average particle diameter of 1 to 200 mμ, with silica of 5 to 80 mμ being particularly preferably used. It is particularly effective in improving adhesion with the upper layer, hardness, or durability, and is generally used as a colloidal solution in which high molecular weight silicic acid anhydride is dispersed in a hydrophilic solvent such as water or alcohol.

In addition to the above-mentioned silica sol, component A includes the general formula R2R.
3Si (OR4) 4-re a b
4-a-b Contains an organosilicon compound and/or a hydrolyzate thereof.

Here, R2 and R3 are each an alkyl group, an alkenyl group, an allyl group, or a hydrocarbon group having a halogen group, an epoxy group, an amino group, a mercapto group, a methacryloxy group or a cyano group, and R4 is a carbon group having 1 to 8 carbon atoms. an alkyl group, an alkoxyalkyl group, an acyl group, and a and b are O
or 1, and a+b is 1 or 2.

Examples of such compounds include methyltrimethoxysilane, methyltriethoxysilane, methyltripropoxysilane, methyltrimethoxyethoxysilane, methyltriacetoxysilane, methyltributoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, vinyltrimethoxysilane, Methoxysilane, vinyltriethoxysilane, vinyltriacetoxysilane, vinyltrimethoxyethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, phenyltriacetoxysilane, γ-
Chloropropyltrimethoxysilane, γ-chloropropyltriethoxysilane, γ-chloropropyltriacetoxysilane, 3.3.3-4-lifluoropropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-aminopropyl Trimethoxysilane, γ
-Aminopropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-mercaptopropyltrimethoxyethoxysilane, γ-mercaptopropyltriethoxysilane, N-β-(aminoethyl)-γ-
Aminopropyltrimethoxysilane, β-cyanoethyltriethoxysilane, methyltriphenoxysilane, chloromethyltrimethoxysilane, chloromethyltriethoxysilane, glycitoxymethyltrimethoxysilane,
Glycidoxymethyltriethoxysilane, α-glycidoxyethyltrimethoxysilane, α-glycidoxyethyltriethoxysilane, β-glycidoxyethyltrimethoxysilane, β-glycidoxyethyltriethoxysilane, α- glycidoxypropyltrimethoxysilane,
α-glycidoxypropyltriethoxysilane, β-glycidoxypropyltrimethoxysilane, β-glycidoxypropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropyltriproboxysilane, γ-glycidoxypropyltributoxysilane, γ-glycidoxypropyltrimethoxyethoxysilane, γ-glycidoxypropyltriphenoxysilane, α-glycidoxybutyltri methoxysilane,
α-glycidoxybutyltriethoxysilane, β-glycidoxybutyltrimethoxysilane, β-glycidoxybutyltriethoxysilane, γ-glycidoxybutyltrimethoxysilane, γ-glycidoxybutyltriethoxysilane, δ-glycidoxybutyltrimethoxysilane, δ-glycidoxybutyltriethoxysilane, (3,
4-Epoxycyclohexyl)methyltrimethoxysilane, (3,4-epoxycyclohexyl)methyltriethoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane Ethoxysilane, β-(3
, 4-epoxycyclohexyl)ethyltripropoxysilane, β-(3,4-epoxycyclohexyl)ethyltriptoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethoxyethoxysilane, β-(
3,4-Epoxycyclohexyl)ethyltriphenoxysilane, γ-(3,4-epoxycyclohexyl)propyltrimethoxysilane, γ-(3,4-epoxycyclohexyl)propyltriethoxysilane, β-(3
, 4-epoxycyclohexyl)butyltrimethoxysilane, β-(3,4-epoxycyclohexyl)butyltriethoxysilane, triazyloxysilane or triphenoxysilanes or their hydrolysates, and dimethyldimethoxysilane. , phenylmethyldimethoxysilane, dimethyljethoxysilane, phenylmethyljethoxysilane, γ-chloropropylmethyldimethoxysilane, γ-chloropropylmethyljethoxysilane, dimethyldiacetoxysilane,
γ-methacryloxypropylmethyldimethoxysilane,
γ-methacryloxypropylmethyljethoxysilane,
γ-Mercaptopropylmethyldimethoxysilane, γ-
Mercaptopropylmethyljethoxysilane, γ-aminopropylmethyldimethoxysilane, γ-aminopropylmethyljethoxysilane, methylvinyldimethoxysilane, methylvinyljethoxysilane, glycidoxymethylmethyldimethoxysilane, glycidoxymethylmethyljethoxy Silane, α-glycidoxyethylmethyldimethoxysilane, α-glycidoxyethylmethyljethoxysilane, β-glycidoxyethylmethyldimethoxysilane, β-glycidoxyethylmethyljethoxysilane, α-glycidoxypropyl Methyldimethoxysilane, α-glycidoxypropylmethyljethoxysilane,
β-glycidoxypropylmethyldimethoxysilane, β
-glycidoxypropylmethyljethoxysilane, γ-
Glycidoxypropylmethyldimethoxysilane, γ-glycidoxypropylmethyljethoxysilane, γ-glycidoxypropylmethyldipropoxysilane, γ-glycidoxypropylmethyldibutoxysilane, γ-glycidoxypropylmethyldimethoxyethoxy Silane, γ-
Glycidoxypropylmethyldiphenoxysilane, γ-
Glycidoxypropylmethyldiacetoxysilane, γ-
Glycidoxypropylethyldimethoxysilane, γ-glycidoxypropylethyljethoxysilane, γ-glycidoxypropylvinyldimethoxysilane, γ-glycidoxypropylvinyljethoxysilane, γ-glycidoxypropylphenyldimethoxysilane Examples are dialkoxysilanes or diacyloxysilanes such as , γ-glycidoxypropylphenyldiethoxysilane.

Such a lower film-forming composition is applied to a substrate and cured by heating. The film thickness is preferably between 10 mμ and 4 μm; if it is thicker than this, problems such as cracks will occur in the film, and if it is thinner, the antistatic properties will be insufficient. Furthermore, if only the lower layer coating is used, there is a problem that it is easily scratched by friction caused by fingernails, etc., and the durability is extremely poor.

The upper layer coating applied on the lower layer coating is 0゜01μ.
Any material may be used as long as it exhibits the desired coating performance at a film thickness of m to 10 μm, but various acrylic resins, urethane resins, epoxy resins, etc. are preferable from the viewpoints of durability, aesthetics, colorability, etc., and surface hardness. For the purpose of imparting the general formula % formula % (where l is 1 to 3, R5 is an alkyl group having 1 to 6 carbon atoms, an alkoxyalkyl group, or an allyl group, and Re is an epoxy group having 10 or less carbon atoms). and R7 is an alkyl group having 1 to 6 carbon atoms, a vinyl group, or an aryl group. Specific representative examples of these organosilicon compounds include glycidoxymethyltrimethoxysilane, glycidoxymethyltriethoxysilane, α-glycidoxyethyltrimethoxysilane, α-glycidoxyethyltriethoxysilane, β-glycidoxyethyltrimethoxysilane, β-glycidoxyethyltriethoxysilane, α-glycidoxypropyltrimethoxysilane, α-
Glycidoxypropyltriethoxysilane, β-glycidoxypropyltrimethoxysilane, β-glycidoxypropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ- Glycidoxypropyltripropoxysilane, γ-glycidoxypropyltributoxysilane, γ-glycidoxypropyltrimethoxyethoxysilane, γ-glycidoxypropyltriphenoxysilane, α-glycidoxybutyltrimethoxysilane, α−
Glycidoxybutyltriethoxysilane, β-glycidoxybutyltrimethoxysilane, β-glycidoxybutyltriethoxysilane, γ-glycidoxybutyltrimethoxysilane, γ-glycidoxybutyltriethoxysilane, δ- Glycidoxybutyltrimethoxysilane, δ
-glycidoxybutyltriethoxysilane, (3,4-
epoxycyclohexyl) methyltrimethoxysilane,
(3,4-epoxycyclohexyl)methyltriethoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, β-(3,4-epoxycyclohexyl)ethyltriethoxysilane, β-(3,4-epoxycyclohexyl)ethyltriethoxysilane
-Epoxycyclohexyl)ethyltripropoxysilane, β-(3,4-epoxycyclohexyl)ethyltributoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethoxyethoxysilane, β-(3,
4-Epoxycyclohexyl)ethyltriphenoxysilane, γ-(3,4-epoxycyclohexyl)propyltrimethoxysilane, γ-(3゜4-epoxycyclohexyl)propyltriethoxysilane, δ-(3,4
-Epoxycyclohexyl)butyltrimethoxysilane, δ-(3,4-epoxycyclohexyl)butyltriethoxysilane, glycidoxymethylmethyldimethoxysilane, glycidoxymethylmethyljethoxysilane,
α-glycidoxyethylmethyldimethoxysilane, α-
Glycidoxyethylmethyljethoxysilane, β-glycidoxyethylmethyldimethoxysilane, β-glycidoxyethylmethyljethoxysilane, α-glycidoxypropylmethyldimethoxysilane, α-glycidoxypropylmethyljethoxy Silane, β-glycidoxypropylmethyldimethoxysilane, β-glycidoxypropylmethyljethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-glycidoxypropylmethyljethoxysilane, γ-glycidoxypropyl Methyldipropoxysilane, γ-glycidoxypropylmethyldiptoxysilane, γ-glycidoxypropylmethyldimethoxyethoxysilane, γ-glycidoxypropylmethyldiphenoxysilane, γ-glycidoxypropyl ethyldimethoxysilane , γ-glycidoxypropylethyljethoxysilane, γ-glycidoxypropylvinyldimethoxysilane, γ-glycidoxypropylvinyljethoxysilane, γ-glycidoxypropylphenyldimethoxysilane, γ-glycidoxypropyl Examples include phenyldiethoxysilane, γ-glycidoxypropyldimethylmonomethoxysilane, γ-glycidoxypropyldimethylmonoethoxysilane, and the like.

Among these, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane,
γ-glycidoxypropyltripropoxysilane, γ-
Glycidoxypropyltributoxysilane, γ-glycidoxypropyltrimethoxyethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, γ-glycidoxypropylmethyldipropoxy Silane, γ-glycidoxypropylmethyldibutoxysilane, γ-glycidoxypropylmethyldimethoxyethoxysilane, β-(3
,4-epoxycyclohexyl)ethyltrimethoxysilane, β-(3,4-epoxycyclohexyl)ethyltriethoxysilane, β-(3,4-epoxycyclohexyl)ethyltripropoxysilane, β-(3,4-epoxycyclohexyl)ethyltripropoxysilane
Hydrolyzates of epoxy group-containing organosilicon compounds such as -epoxycyclohexyl)ethyltributoxysilane and β-(3,4-epoxycyclohexyl)ethyltritoxyethoxysilane are particularly effective in the present invention.

These organosilicon compounds are used after being hydrolyzed in order to lower the curing temperature and further promote curing. Hydrolysis is produced by adding and stirring pure water or an acidic aqueous solution such as hydrochloric acid, acetic acid, or sulfuric acid. Furthermore, the degree of hydrolysis can be easily controlled by adjusting the amount of pure water or acidic aqueous solution added. During hydrolysis, it is particularly preferable to add pure water or an acidic aqueous solution in an amount equal to or more than 3 times the mole of the alkoxy group, from the viewpoint of accelerating curing.

During hydrolysis, alcohol and other substances are produced, so it is possible to hydrolyze without a solvent, but in order to make the hydrolysis more even, it is possible to mix the organosilicon compound and a solvent before hydrolysis. is also possible. Depending on the purpose, it is also possible to remove an appropriate amount of the hydrolyzed alcohol etc. under heating and/or reduced pressure before use, and it is also possible to add an appropriate solvent afterwards. These solvents include alcohols, esters, ethers,
Examples include solvents such as ketones, halogenated hydrocarbons, and aromatic hydrocarbons such as toluene and xylene. Moreover, these solvents can also be used as a mixed solvent of two or more types as required. Furthermore, depending on the purpose, it is possible to accelerate the hydrolysis reaction and further advance reactions such as precondensation by heating above room temperature, or to suppress precondensation, the hydrolysis temperature can be lowered to below room temperature. Needless to say, it is possible to do so.

It is also possible to add curing catalysts, curing accelerators, crosslinking agents, etc. for the same purpose. Examples of these include aluminum compounds such as aluminum alkoxide and aluminum acetylacetonate, other metal complex compounds, imidazole, and organic acid anhydrides. Epoxy resin curing agents such as various compounds and various amine compounds can be used.

Further, in the present invention, hydrolysates of various silicon tetraalkoxides and condensation products thereof are suitable as examples for the purpose of enhancing antistatic properties. Specific examples include methyl silicate, ethyl silicate, n-propyl silicate, i-propyl silicate, n-butyl silicate, t-butyl silicate, and i-butyl silicate.

Furthermore, two or more types of coating compositions for forming these upper layer films can be used in combination depending on the purpose.

The present invention is used by dissolving or dispersing the upper layer film-forming composition as in the above example in a suitable solvent and applying it as a coating composition onto the underfoot film made of component A. The thickness of the coating is 0.01 μm to 10 μm, preferably 0.0 μm.
A suitable range is 2 μm to 5 μm. That is, if it becomes thicker than this, no improvement in antistatic properties will be observed. In addition, if it is thin, problems such as insufficient surface hardness tend to occur. The upper layer coating can also consist of two or more layers if the above conditions are met.

In addition, in the method of the present invention, by appropriately selecting the thickness and material of the multilayer film containing component A and the upper layer film coated thereon, in addition to improving surface hardness, durability, etc. It is possible to provide not only the function of preventing reflection of materials but also the function of increasing reflection. The applied various coating compositions can be heat-cured and/or dried in stages, or after the lower layer is pre-cured and/or dried, the upper layer is coated, heat-cured and/or dried. It is also possible. As a heating method, hot air, infrared rays, etc. can be used. The heating temperature should also be determined by the substrate to be applied and the coating composition used, but is usually 50 to 2
50°C, more preferably 60-200°C is used.

In the case of a lower coating film, curing or drying is insufficient at lower temperatures, and thermal decomposition occurs at higher temperatures, resulting in problems such as yellowing.

The upper coating can also be cured by utilizing curable functional groups, such as polymerization or double bonds in prepolymers, using radiation such as ultraviolet rays, electron beams, and gamma rays.

Further, it is possible to add to component A of the present invention a compound represented by the following general formula % (), a hydrolyzate thereof, and/or an oligomer or polymer obtained by condensation polymerization thereof.

Here, M is Ti (IV), Si (IV), Zr (
TV), m+n is an integer from 1 to 4, m and n are each 0.1.
2.3 or 4, R and R' are alkyl groups, alkoxyalkyl groups, or acyl groups having 1 to 10 carbon atoms, and X is M' COCH2COM 2 and M3C0CH2C
00M' (where M', M2, M3 and M4 have 6 carbon atoms)
The following alkyl group).

Such titanium, silicon, and zirconium compounds are alkoxides, carboxylates, and/or chelates of these compounds, and these compounds are present in the film-forming component in the lower film-forming composition in an amount of 10% in terms of M02.
．． It is preferable that the necessary amount is provided to contain 0% by weight or more. (Here, M represents the previously defined tetravalent element).

By containing these amounts, it becomes possible to exhibit sufficient antistatic properties.

Specific examples of the compound represented by the above general formula include:
Titanium tetraethoxide, titanium tetra-i-propoxide, titanium tetra-n-propoxide, titanium tetra-n-butoxide, titanium tetra-5ee-butoxide, titanium tetra-tert-butoxide, aluminum triethoxide, aluminum treaty Propoxide, aluminum tributoxide, zirconium tetraethoxide, zirconium tetra-i-propoxide, zirconium tetra-n-propoxide, zirconium tetra-n-butoxide, zirconium tetra-5ee-
Alcoholate compounds such as butoxide, zirconium tetra-1er1-butoxide, methyl silicate, ethyl silicate, n-propyl silicate, i-propyl silicate, n-butyl silicate, 5ec-butyl silicate and t-butyl silicate, di-isopropoxy titanium Bisacetylacetonate, dibutoxytitanium bisacetylacetonate, di-ethoxytitanium bisacetylacetonate, tri-n-butoxyzirconium monoethylacetoacetate, zirconium monobutoxytrisacetylacetonate, zirconium dibutoxybisacetylacetonate, zirconium tri- Examples include chelate compounds such as butoxyacetylacetonate, zirconium monobutoxytrisethylacetoacetate, and zirconium butoxybisethylacetoacetate.

The base material of the present invention is not particularly limited, but from the viewpoint of liquid coating, glass and plastic materials give effective results.

The above plastic materials include polymethyl methacrylate and its copolymers, polycarbonate, diethylene glycol bisallyl carbonate (CR-39),
Polyesters, particularly polyethylene terephthalate, unsaturated polyesters, acrylonitrile-styrene copolymers, vinyl chloride, polyurethanes, epoxy resins, and the like are preferred.

Moreover, it can also be preferably used for glass.

Furthermore, it can be preferably applied to base materials such as the above-mentioned plastics and glass coated with coating materials.

In particular, various physical properties such as adhesion, hardness, chemical resistance, durability, and color development can be improved by the coating material further below the lower layer coating of the present invention.

In addition, these coating compositions contain various interfaces to improve smoothness, antifoaming agents, ultraviolet absorbers as film improvers, and antioxidants to improve coating workability, as well as antioxidants to provide antifogging properties. Additives such as activators can be used. Furthermore, during coating operations, these compositions are usually diluted with a volatile solvent before being applied. The solvent to be used is not particularly limited, but should be determined in consideration of the stability of the composition, wettability to the substrate, volatility, etc. In addition, there are not only one type of solvent but also two types of solvents.
It is also possible to use a mixture of more than one species.

Some of these solvents are particularly useful for stabilizing the underlying film-forming coating composition, such as alcohols having 8 or less carbon atoms, monoalkyl ethers of ethylene glycol or diethylene glycol, and diketones such as acetylacetone. and ketoesters such as ethyl acetoacetate are particularly effective against alkoxides and chelate compounds such as titanium and zirconium.

Here, the coating composition is a composition having a viscosity within a range that can be applied in normal coating operations, and which has a viscosity of 10% at the application temperature.
Poise or less, preferably 1 poise or less is used. That is, it is difficult to obtain a uniform coating with a coating composition having a viscosity higher than this. As a coating method, methods used in normal coating operations are possible, but from the viewpoint of controlling the thickness of the thin film, curtain flow coating, dip coating, spin coating, etc. are preferable.

These materials exhibit their effects in optical lenses for glasses, cameras, etc., covers for various display devices, and especially iron plates for front panels for CRTs.

In addition, for various coatings, various chemical treatments, such as hot water immersion, solvent immersion, redox agent treatment, acid and alkali treatments, and physical treatments, such as low temperature plasma treatment, corona discharge treatment, and ultraviolet irradiation, are applied to the layers in contact with each other. It is also possible to improve adhesion and wettability by applying it to.

[Examples] The present invention will be explained in detail below using Examples, but the present invention is not limited thereto.

Example 1 (1) Preparation of lower layer coating composition (a) Preparation of γ-glycidoxypropylmethyljethoxysilane hydrolyzate γ-glycidoxypropylmethyljethoxysilane 50
g while stirring and controlling the liquid temperature to 10°C.
7.3 g of 0.05N hydrochloric acid aqueous solution was added dropwise and mixed to obtain a hydrolyzate.

(b) Preparation of coating composition The hydrolyzate prepared in (1) and (a) above was mixed at 1°6
g1 5 g of methanol-dispersed colloidal silica.1 182.5 g of methyl isobutyl ketone and 0.13 g of aluminum acetylacetonate are added and stirred until homogeneous. Thereafter, 10.8 g of tetra-n-butyl titanate was added under stirring to obtain a coating composition.

■ Preparation of upper layer coating composition 29.4 g of the hydrolyzate prepared in (1) (a) above.

0.23 g of silicone surfactant, 419.5 g of n-propyl alcohol, and 0.9 g of aluminum acetylacetonate were added, and the mixture was thoroughly stirred until uniform, to obtain a coating composition.

■) Coating and curing First, using the coating composition prepared in the previous section (1), a diethylene glycol bisallyl carbonate polymer lens (diameter 7
5 reviews, thickness 2. 1 mm, CR-39 Praluns) by dipping method. The coating conditions are a pulling speed of 10cm/
The coated lenses were heated and cured for 1 hour in a hot air dryer at 80°C.

After this, using the coating composition prepared in the previous section (■),
It was coated on top of the bottom layer in the same manner as the bottom layer. The coated lenses were heat cured at 80° C. for 2 hours.

(4) Test Results The performance of the obtained lenses with multilayer coatings was tested according to the following method. The results are shown in Table 1.

(b) Appearance The transparency, coloration, and presence or absence of cracks were observed with the naked eye.

(b) Total light transmittance was measured using a 5M-3 color computer (manufactured by Suga Test Instruments Co., Ltd.).

(c) Using steel wool with a hardness of #0000, multiple coatings were rubbed and the degree of scratching was judged.The criteria were: A...Slight scratches occur when rubbed hard.B...Slight scratches occur when rubbed lightly. A wound occurs.

3) Place 100 goblets reaching CR-39 prairons at 1 mm intervals on the adhesive multilayer film, and firmly stick cellophane adhesive tape (trade name "Cello Tape" manufactured by Nichiban Co., Ltd.).
It was rapidly peeled off in the 0 degree direction and the presence or absence of paint film peeling was examined.

(e) Dyeing properties Dyeing was carried out at 93°C for 15 minutes using disperse dyes consisting of red, blue, and yellow. The stainability was measured using the same device as in (b).

(f) Antistatic property After being left overnight at 20° C. and 65% RH, the multilayer film was rubbed with deerskin and judged by the degree of adhesion of ash.

A: Ash does not adhere B: Ash adheres [Effects of the Invention] The present invention makes it possible to select from a wide range of coatings having various surface properties, especially surface hardness, antireflection properties, It is possible to provide a multilayer coating that is excellent in durability, transparency, impact resistance, and more preferably in antistatic properties.

Patent applicant Higashi Shikikai Co., Ltd.

Claims (1)

[Claims] (1) A multilayer coating applied to the surface of a substrate, in which the lower layer coating is obtained by curing a composition containing the following component A, and the upper layer coating has a thickness of 0.01 μm to 10 μm.
A multilayer film characterized by being a film of. A, silica sol with an average particle diameter of 1 to 200 mμ, and general formula R^2_aR^3_bSi(OR^4)_4_-
An organosilicon compound represented by _a_-_b and/or a hydrolyzate thereof. Here, R^2 and R^3 are each an alkyl group, an alkenyl group, an allyl group, or a hydrocarbon group having a halogen group, an epoxy group, an amino group, a mercapto group, a methacryloxy group or a cyano group, and R^4 is a carbon group. It is an alkyl group, an alkoxyalkyl group, or an acyl group having 1 to 8 in number, a and b are 0 or 1, and a+b is 1 or 2.