JPS62153147A - Article having anti-fogging property - Google Patents

Abstract

PURPOSE:To obtain an article having coats with improved anti-fogging properties and adhesive strength, by laminating a coat of a silane coupling agent, and coats of polyvinyl alcohol, fine particulate silica, organosilicon compound and/or hydrolyzate thereof one after another on a substrate. CONSTITUTION:The following coats (A) and (B) are laminated on a substrate in the order described below to give an article having anti-fogging properties; (A) is silane coupling agent and (A) a cured coat obtained from the following components (a), (b) and (c); (a) 100pts.wt. polyvinyl alcohol, (b) 60-300pts.wt. fine particulate silica having 5-200mu average particle size and (c) 0.5-30pts.wt. organosilicon compound expressed by the formula and/or hydrolyzate thereof. The content of carbon and silicon elements in the cured coat is 0.7/1-1/2 weight ratio (C/Si) of carbon to Si and the above-mentioned weight ratio in the surface layer is higher than the weight ratio (C/Si) in the total cured coat and is >=1.7/1.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an article having antifogging properties, durability, surface hardness, etc.

[Traditional art] Plus Deck and Mugei Karasu have traditionally been widely used in products such as window glass, mirror surfaces, automobile front glasses, side glasses, rear windows, and eyeglass lenses, taking advantage of their properties as transparent base materials. ing. However, the disadvantage of products using plastic and glass substrates is that when they are used in high-temperature, high-humidity pumping places or on interfaces with large temperature and humidity differences, condensation occurs on the surface of the product, which can cause the surface of the product to deteriorate. It is to become cloudy. In particular, it is a serious safety problem that the surfaces of products such as window glasses, glass used in automobiles, eyeglass lenses, mirrors, etc. tend to fog up easily. Accordingly, there have been demands for improvements in these from various quarters, and various attempts have been made to provide antifogging properties and durability to various articles.

As the simplest method for achieving an antifogging effect, a method for improving the wettability of the surface of an article by applying or mixing a hydrophilic substance such as a surfactant has been proposed (US Pat. No. 3.47).
9.308). In addition, a hydrophilic polymer has also been applied to impart durability to anti-fog properties. A proposal was made to use polyvinyl alcohol in this.

For example, US Pat. No. 4,127,682 proposes an antifogging agent of polyvinyl alcohol crosslinked with zirconium nitrate and formaldehyde.

On the other hand, it is known that polyvinyl alcohol can be crosslinked with particulate silica to provide a water-resistant coating (U.S. Pat. No. 3,773,776).

Additionally, curable coating compositions based on polyvinyl alcoholex have also been proposed (US Pat. No. 4,016,129).

Furthermore, it has been proposed to improve abrasion resistance and antifogging properties by using a discontinuous inorganic film and a hydrophilic resin (US Pat. No. 3,895, '155).

Until now, wear-resistant coating compositions using silane compounds and silica particles have been proposed (U.S. Patent No. 4.
No. 027,073 and U.S. Patent No. 4.211.823
issue). These are particularly effective in hardening the surface of plastic substrates, but do not have antifogging properties.

The present inventors also proposed a composition that solved these problems, and in JP-A-58-32664, proposed a method for producing a coating film with an improved balance between antifogging properties, abrasion resistance, and durability.

[Problems to be solved by the invention] Methods such as coating a surfactant such as in U.S. Patent No. 3,479.308 only temporarily provide antifogging properties, and a continuous effect cannot be expected. I can't.

Also, U.S. Patent No. 4,127,682M, U.S. Patent No. 3
．． No. 773.776, as well as U.S. Patent No. 4.016.
The coating proposed by No. 129 using polyvinyl alcohol has an insufficient balance between anti-fogging properties and hardness, and is therefore impractical.

On the other hand, the technology according to US Pat. No. 3,895,155 is not sufficiently durable and suffers from swelling, for example due to the low water resistance of the hydrophilic polymer.

In addition, the technology disclosed in Japanese Patent Application Laid-Open No. 58-32664Q creates a coating film with an improved balance of abrasion resistance, antifogging properties, and even durability, but the adhesion to 5Q GL glass is insufficient. However, there is a problem in that it is of limited practicality.

The present invention solves these problems all at once.

[Means for Solving the Problems] The present invention relates to a glass article having antifogging properties, characterized in that the following coatings A and B are laminated in this order on a glass substrate.

A. Silane coupling agent B. A cured film made of 1q from the following components A, 2 and C, and the elemental content of carbon and silicon in the cured film has a carbon/silicon (C/S i ) weight ratio of about 0.7.
/1.0 to 2.0/1.0, and the above weight ratio in the surface layer is larger than the C/Si weight ratio of the entire cured film, and 1.7/1.0 or more. A coating that is.

stomach. Polyvinyl alcohol 100 car parts. Fine particulate silica with an average particle diameter of approximately 5 to 200 mμ
60-300 members c. General formula R1R2 Si(OR
0.5 to 30 parts by weight of a silicon compound and/or its hydrolyzate represented by 3>3 (where R1 is an Fg group having 1 to 10 carbon atoms, R2 is a Fg group having 1 to 10 carbon atoms)
~6 hydrocarbon group, R3 is an alkyl group having 1 to 8 carbon atoms,
an alkoxyalkyl group or an acyl group, and a is O or 1>.

The substrate used in the present invention is not particularly limited as long as it requires antifogging properties.

Here, specific examples of the silane coupling agent used as the coating film A include methyl silicate, ethyl silicate, n-propyl silicate, 1-propyl silicate, n-butyl silicate, 5ec-butyl silicate, and t-butyl silicate. Tetraalkoxysilanes such as, and their hydrolysates, as well as methyltrimethoxysilane, methyltriethoxysilane, methyltrimethoxyethoxysilane, methyltriacetoxysilane, methyltributoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, Vinyltrimethoxysilane, vinyltriethoxysilane, vinyltriacetoxysilane, vinyltrimethoxyethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, phenyl-1-lyacetoxysilane, γ-chloropropyltrimethoxysilane, γ-chloro Propyltriethoxysilane, T-chloropropyltriacetoxysilane, 3.3.3-trifluoropropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-aminopropyltrimethoxysilane, γ
-Aminopropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, N-8-(aminoethyl)-γ-
Aminopropyltrimethoxysilane, β-cyanoethyltriethoxysilane, methyltriphenoxysilane, chloromethyltrimethoxysilane, chloromethyltriethoxysilane, glycidoxymethyltrimethoxysilane,
Glycidoxymethyltriethoxysilane, α-glycidoxyethyltrimethoxysilane, α-glycidoxyethyltriethoxysilane, B-glycidoxyethyltrimethoxysilane, β-glycidoxyethyltriethoxysilane, α- glycidoxypropyltrimethoxysilane,
α-glycidoxypropyltriethoxysilane, β-glycidoxypropyltrimethoxysilane, β-glycidoxypropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-Glycidoxypropyltriproboxysilane, T-glycidoxypropyltributoxysilane, T-glycidoxypropyltrimethoxyethoxysilane, γ-glycidoxypropyltriphenoxysilane, α-glycidoxybutyl trimethoxysilane,
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)ethyltributoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethoxyethoxysilane, β-(
3,4-epoxycyclobexyl)ethyltriphenoxysilane, γ-(3,4-epoxycyclohexyl)propyltrimethoxysilane, γ-(3,4-epoxycyclohexyl)propyltriethoxysilane, β-(3
, 4-epoxycyclohexyl> butyltrimethoxysilane, trialkoxysilane such as 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, glycidoxymethylmethyljethoxysilane Toxysilane, α-glycidoxyethylmethyldimethoxysilane, α-glycidoxyethylmethyljethoxysilane, β-glycidoxyethylmethyldimethoxysilane, β-glycidoxyethylmethyljethoxysilane, α-glycidoxy Propylmethyldimethoxysilane, α-glycidoxypropylmethyljethoxysilane, β-glycidoxypropylmethyldimethoxysilane,
β-glycidoxypropylmethyljethoxysilane, γ
-Glycidoxypropylmethyldimethoxysilane, γ-glycidoxypropylmethyljethoxysilane, γ-glycidoxypropylmethyldipropoxysilane, γ-glycidoxypropylmethyldibutoxysilane, γ-glycidoxypropyl Methyldimethoxyethoxysilane, γ
-Glycidoxypropylmethyldiphenoxysilane, γ
-glycidoxypropylethyldimethoxysilane, γ-glycidoxypropylethyljethoxysilane, γ-glycidoxypropylethyldipropoxysilane, γ-crisitoxypropylvinyldimethoxysilane, r-glycidoxypropylvinyldiethoxysilane , γ-glycidoxypropylphenyldimethoxysilane, γ-glycidoxypropylphenyldiethoxysilane, dialkoxysilanes, diphenoxysilanes, diacyloxysilanes, or hydrolysates thereof.

It is also possible to add one or more types of these silicon compounds. Hydrolyzates of these silicon compounds are preferably used, and particularly for the purpose of improving adhesion, silicon compounds containing at least one group selected from an epoxy group, a glycidoxy group, or an amino group are preferably used.

Although the coating amount is not particularly limited, it is preferable that the coating film has a thickness of 1 μm or less.

The coating A may be heated after coating, and then the components forming the coating B may be applied, but it is preferable to apply the coating composition A as it is or by blowing the coating composition (with some heat and drying). Coating composition B is applied immediately after the solvent is removed because it is easy to operate and improves the adhesion of the film.

In the present invention, the above-mentioned B coating is provided on the above-mentioned H coating layer. Here, the polyvinyl alcohol used as component A contained in the B coating is a polyvinyl ester such as polyvinyl acetate. It refers to polyvinyl alcohol obtained by partial or complete hydrolysis, and among them, polyvinyl alcohol having an average degree of polymerization of 250 to 3000 and a degree of saponification of 70 mol% or more is preferably used in the present invention. Polyvinyl alcohol with an average degree of polymerization of less than 250 has poor durability, especially water resistance, and
If it is larger, the viscosity will increase when used as a paint, causing problems in terms of work, such as difficulty in obtaining a smooth coating film. In general, if the degree of saponification is lower than 70 mol%, sufficient performance in terms of anti-fogging properties cannot be expected.

Furthermore, an effective example of the particulate silica having an average particle diameter of 5 to 200 mμ, which is a daily component, is silica sol. Silica sols are colloidal dispersions of high molecular weight silicic anhydride in organic solvents such as water and/or alcohols. For purposes of the present invention, the average particle size is approximately 50 to
A diameter of 200 mμ is used, but a diameter of about 7 to 50 mμ is particularly preferred. If the average particle size is less than about 5μ, the stability of the dispersion state is poor and it is difficult to obtain a uniform crystalline state; The quality is poor, and you can only get things that are very cloudy.

The silicon compound represented by the general formula R1R2Sj (OR3)3-a, which is the component (3), is a necessary component for improving water resistance and adhesion to the base material. Glycidoxyethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, β-glycidoxypropyltrimethoxysilane, β-glycidoxyethylmethyldimethoxysilane, β- glycidoxyethylmethyljethoxysilane,
γ-glycidoxypropylmethyldimethoxysilane, γ
-glycidoxypropylmethyljethoxysilane, β-
Glycidoxyethylethyldimethoxysilane, γ-glycidoxypropylethyldimethoxysilane, γ-glycidoxypropylethyljethoxysilane, β-glycidoxypropylethyljethoxysilane, β-glycidoxyethylpropyldimethoxysilane, β-(3,4 epoxycyclohexyl>ethyltrimethoxysilane, β-
(3,4 epoxycyclohexyl)ethyltriethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltriacetoxysilane, vinyltrimethoxyethoxysilane, γ-chloropropyltrimethoxysilane , γ-chloropropyltriethoxysilane,
γ-chloropropyltripropoxysilane, γ-chloropropyltributoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, γ-trifluoropropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, dimethyldimethoxysilane, γ
-chloropropylmethyldimethoxysilane, γ-methacryloxypropylmethyldimethoxysilane, and the like. Moreover, these compounds can be used not only alone but also in combination of two or more.

When using the above-mentioned organosilicon compound as component (iii), it can be added as a component as it is, or it can be hydrolyzed in advance and then the silane hydrolyzate is added thereto.

For hydrolysis, conventional methods can be used, such as hydrolysis using an inorganic acid such as hydrochloric acid, an organic acid such as acetic acid, or an alkali such as caustic soda, or using only water.

Each of the eight coatings of the present invention has the above-mentioned components (A), (3), and (C) as essential components, and if one of these is missing, the coating should be satisfactory in terms of antifogging properties and durability, which are the objectives of the present invention. cannot be obtained.

Further, the present invention is a cured coating having a surface layer portion which essentially contains a relatively larger amount of component A than in the coating B.

The surface layer refers to the outermost layer that comes into contact with the outside air and can be distinguished from the layer below by its composition.

The base material may be treated with activated gas, physical treatment such as sandblasting, or chemical treatment with a base, a base, an oxidizing agent, etc. in order to improve the adhesion with the A coating.

If the content of the components in the surface layer is less than the above-mentioned value, the water resistance will be reduced, and if it is more than this, the antifogging property will be significantly reduced.

The thickness of the surface layer portion is preferably in the range of 0.001 μm to 5 μm, and if it is thinner than this, the antifogging property will be reduced, and if it is thicker, the water resistance will be reduced.

Water resistance and vf! If the amount exceeds this level, cracks will occur during or after curing, and the coating will deteriorate. The thickness of the entire coating is preferably 0.1 μm or more; if it is less than this, the antifogging properties will be insufficient and the hardness will also decrease. There is no particular restriction on the thickness, but in consideration of painting workability, a thickness of about 30 # or less is preferably used.

In addition to the essential components listed above, the film-forming composition B of the present invention may also contain solvents, additives, various modifiers, and the like.

As the solvent, for example, water, various alcohols, ketones, esters, ethers, cyclic ethers, dimethylformamide, dimethyl sulfoxide, etc. can be used as appropriate.

As additives, various surfactants can be used for the purpose of improving surface smoothness, and examples include silicone compounds, fluorine surfactants, and surfactants. Furthermore, as a modifier, organic polymers having good compatibility with the composition of the present invention may be used, such as droxyethyl cellulose, polyhydroxyethyl MEC 1 route, or copolymers thereof, alcohol-soluble nylon, polyacrylamide, polyvinylpyrrolidone, or their copolymers. Examples include copolymers. It is also possible to add tetrafunctional silane compounds such as ethyl silicate, n-propyl silicate, i-propyl silicate, n-butyl silicate, i-butyl silicate, and t-butyl silicate. Examples of modifiers that can be added include various epoxy resins, melamine resins, and amide resins.

If necessary, for the purpose of accelerating curing, condensation of silanol and/or silanol and water i! Various catalysts known as i% reaction catalysts are used, but the general formula is Ar1-
Xn-Y3. An aluminum chelate compound represented by can be preferably used.

(Here, X is a lower alkoxy group, Y is M1COCHpC
Ligands (Ml, M2.M
3 and M4 are lower alkyl groups), n is 0.1 or 2
).

Various types of aluminum chelate compounds can be used, but examples of preferred compounds from the viewpoint of catalytic activity, solubility in the composition, and stability include aluminum acetylacetonate, aluminum ethyl acetoacetate bisacetylacetonate, and aluminum. Examples include acetoacetate acetylacetonate, aluminum morobutoxide monoethylacetoacetate, aluminum diamypropoxide monomethylacetoacetate, and mixtures of these compounds can also be used.

These additional components other than the essential components are used to improve the heat resistance, weather resistance, water resistance, adhesion, or chemical resistance of the coating film formed from the antifogging composition of the present invention, to which the present invention is applied. Various practical characteristics can be improved depending on the situation.

Furthermore, dyes and pigments may be added to one or both of the surface layer portion and the lower layer portion of the A coating and B coating of the present invention to the extent that transparency is not impaired, thereby coloring the cured coating formed from the composition. It is possible.

The composition of the present invention can be obtained by, for example, simply mixing each component, or depending on the component, using a material that has undergone hydrolysis or other treatment in advance and roughly mixing it with other components. All of these methods are useful for producing the composition of the present invention.

As described in the present invention, in order to specifically produce a film in which the component A in the surface layer is relatively larger than the component A in the rest, the lower layer forming composition is coated on the substrate having the coating A by $1. , two coats are performed by roughly applying the surface layer forming composition thereon.

In this case, the lower layer forming composition may be applied and cured, and then the surface layer forming composition may be applied and cured. Alternatively, the lower layer forming composition may be coated with m5, and after a slight setting, the surface layer forming composition may be applied and cured. It is also possible to use wet-on-wet coating to cure coatings with different surface layer compositions all at once. Formation of the cured film is usually carried out at 50 to 25 O'C. If the temperature is too low, curing will be insufficient, and if the temperature is too high, the coating will become discolored or deteriorate.

In addition, the coating composition is applied in one coat, and the surface layer and/or component C is reduced by a cured film or a wet treatment after curing, so that the surface layer has a relatively larger amount of component A than the total component A. wo can be manufactured.

Here, the wet treatment refers to immersing the film in water or an organic solvent, or leaving it in a high humidity atmosphere. At this time, it is heated if necessary.

Furthermore, instead of the above-mentioned wet treatment, the surface of the B coating can be covered with gauze.
A similar film can also be produced by a friction treatment in which the material is wiped with a flexible article such as paper, or an article made more flexible by moistening it with water. .

The protective film of the present invention can be applied to various base materials, and there are no particular restrictions on the base material for T2 coating as long as it does not impair the properties of the present invention, but in general, The coating of the present invention is preferably used for inorganic glass lenses, windows of bathrooms, windows of automobiles, trains, etc., as examples of articles to be coated that have remarkable characteristics and have great practical value.

Methods for applying the respective compositions of Coating A and Coating B to the substrate to be coated include, for example, brush coating, dip coating, spin coating, flow coating, spray coating, roll coating, curtain flow coating, etc. commonly known in the art. It is possible to use various methods that have been described.

[Example] Hereinafter, the present invention will be explained in more detail with reference to Examples.

Example 1 (1) Preparation of A coating (a) Preparation of coating composition γ-glycidoxypropyltrimethoxysilane 3.50
While controlling the temperature to 10'C, 0.8C of 0.01N aqueous hydrochloric acid solution was added dropwise and mixed with stirring to obtain a hydrolyzate. To this hydrolyzate, 495.7 CI of a solvent of n-propertool/methanol mixture (1/1 weight ratio) was added and sufficiently stirred to obtain a coating composition.

(b) Coating and drying The coating composition obtained in (a) above was pulled onto a hot glass plate (3 x 60 x 900 mm) at a speed of 20 cm/
Coating was carried out by the dipping method under conditions of min. The coated board is 11
It was dried at 0'C for 10 minutes.

<2> B? t:lPi! (a) Preparation of coating composition■ Preparation of γ-glycidoxypropyltrimethoxysilane hydrolyzate 236q of γ-glycidoxypropyltrimethoxysilane was charged into a reactor equipped with a rotor, and a wave sound was applied. 0.01 while keeping at 10'C and stirring with magnetic stirrer.
A normal aqueous hydrochloric acid solution 54C1 is gradually added dropwise. After the dropwise addition was completed, cooling was stopped to obtain a hydrolyzate of γ-glycidoxypropyltrimethoxysilane.

◎ Paint preparation Polyvinyl alcohol (Nippon Gosei Kagaku Kogyo Co., Ltd. product)
AL-06, degree of saponification 91.0-94.0 mol%) 1
After weighing 5% by weight aqueous solution 250Q into a beaker,
While stirring, 28Q of water, 10.4CI of the γ-glycidoxypropyltrimethoxysilane hydrolyzate, and 105q of methanol-dispersed colloidal silica (solid content 30%, average particle size 13±1 mμ) are added, respectively. To this mixed dispersion were added 105 Cl of 1,4 dioxane, 0.24 C7 of a fluorosurfactant, and 1.5 g of aluminum acetylacetonate, and thoroughly stirred and mixed to obtain paint B.

The content of carbon and silicon in the film-forming components of this paint was approximately 1.6 in C/Si weight ratio.

(B) Coating and curing: Coating B was coated on the inorganic glass with coating A obtained in (1) above using a dipping method at a pulling speed of 10 cm/min, and dried by heating in a hot air drying chamber at 80'C for 10 minutes. did. After curing by heating in a hot air drying hall at 130'C for 2 hours,
It was immersed in hot water at 90'C for 1 hour, and dried at 80'C for 30 minutes as an after cure.

(3) Test results The coated glass plate was subjected to the following tests.

(b) Adhesion test The coated glass plate was subjected to the following tests.

Using a steel knife, insert 100 goblets reaching the substrate of 1 mm square onto the glass coating surface, then firmly stick cellophane adhesive tape (trade name: "Cello Tape", manufactured by Nichiban Co., Ltd.) in a 90 degree direction. It was rapidly peeled off and the presence or absence of paint film peeling was examined.

(Mouth) After the anti-fogging test sample was left in a room at 23°C and 150% RH for one day and night, it was examined to see if it fogged when exhaled air was blown onto it. Immediately after, fogging appeared on the entire surface of the glass.

As a result of the above results, no peeling of the coating film was observed in the adhesion test, indicating strong adhesion and excellent anti-directional properties.

Example 2 A test was carried out in the same manner as in Example 1 except that the plugging material was changed to polycarbonate and the coating composition of the A film was changed to the following (1).

(1) Preparation of paint N-β(aminoethyl>γ-aminopropyltrimethoxysilane 1.'82Q) was mixed with n-propatool/methanol mixture (1/1 weight ratio> 247°740) and stirred. After adding 0.01N hydrochloric acid 0°45Q and stirring thoroughly, the mixture was left at room temperature for 24 hours to prepare a coating composition.

(2) Test results (a) Adhesion test As a result of the same test as in Example 1, it had the same strong Mitsuya force.

(b) Anti-fog test It had the same excellent antifogging properties as Example 1.

Comparative Example 1 Using non-density glass and polycarbonate as the base material,
Only the B coating was applied in the same manner as in Example 1 for coating.

The resulting coated article has a rating of 9 for any base material.
The film peeled off during the hot water treatment at 0'C, and a coating film with desirable anti-oxidation properties could not be obtained.

[Effects of the Invention] According to the present invention, it has become possible to provide an article having a coating film having excellent antifogging properties and excellent adhesion strength. As a result, it has become suitable for use in durable consumer goods such as automobiles and trains.

Claims (2)

[Claims] (1) An article having antifogging properties, characterized in that the following coatings A and B are laminated in this order on a substrate. A, a silane coupling agent B, and a cured film obtained from the following components A, B, and C, in which the elemental content of carbon and silicon in the cured film is approximately in the carbon/silicon (C/Si) weight ratio. 0.7/1.0
~2.0/1.0, and the above weight ratio in the surface layer is larger than the C/Si weight ratio of the entire cured film, and is 1.7/1.0 or more. (a) 100 parts by weight of polyvinyl alcohol (b) Fine particulate silica with an average particle diameter of approximately 5 to 200 mμ 6
0 to 300 parts by weight c, general formula R^1R^2_aSi(OR^3)_3_-
0.5 to 30 parts by weight of an organosilicon compound and/or its hydrolyzate represented by __a (where R^1 is an organic group having 1 to 10 carbon atoms, R^2 is a hydrocarbon having 1 to 6 carbon atoms) group, R^3 is an alkyl group, alkoxyalkyl group, or acyl group having 1 to 8 carbon atoms, and a is 0 or 1). (2) The article having antifogging properties according to claim (1), wherein the silane coupling agent is an organic silane compound having an epoxy group, a glycidoxy group, and/or an amino group.