JPH1121512A - Resin composition for hydrophilic coating film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin composition which can give hydrophilic coating films having excellent clarity, persistent antifogging performances, durability, water resistance and scratch resistance. SOLUTION: This composition is prepared by compatibilizing on a molecular level a resin having in the molecule a hydrophilic moiety comprising an alkali metal salt of at least one acid selected from among sulfonic acids, phosphoric acids and carboxylic acids with a three-dimensional structure of silicon dioxide or a precursor which can give a three-dimensional structure of silicon dioxide.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a coating resin composition. More specifically, the present invention relates to a hydrophilic coating resin composition which forms a hydrophilic coating film having excellent antifogging properties, scratch resistance, water resistance and durability by being applied to the surface of glass, plastic, or the like. .

[0002]

2. Description of the Related Art Transparent substrates such as glass and transparent plastic materials have been widely used for articles such as window glasses, mirrors, spectacle lenses, building materials, and automobiles by utilizing their properties. However, these substrates have the disadvantage that when the surface temperature falls below the dew point, moisture in the air condenses on the surface to form fine water droplets, and irregular reflection of light causes fogging. In particular, it is a serious problem that the surface of a transparent substrate, such as a window glass, a spectacle lens, or a mirror, is easily fogged or damaged.

[0003] Therefore, in order to improve this drawback, the water wettability of the surface of the substrate is improved from the viewpoint that the formation of fine water droplets causing fogging is based on a surface chemistry factor between the substrate and water. Processing solutions have been proposed. For example, a method of applying various surfactants, polysaccharides, glycerin, polyvinyl alcohol, polyalkylene glycol, hydroxyalkyl acrylate, and other various hydrophilic polymers to a substrate has been known for a long time. Also, JP-A-58-32664
In Japanese Patent Application Laid-Open Publication No. H11-264, an anti-fogging coating comprising polyvinyl alcohol, particulate silica and an organosilicon compound with improved durability is proposed. Also, JP-A-55-999
No. 87 proposes a method of coating the surface of a transparent object with an inorganic-organic composite reactant comprising water-dispersible silica, a water-soluble or water-dispersible organic polymer resin and a reactive silane compound. I have. Further, Japanese Patent Application Laid-Open No. 7-150072
In Japanese Patent Application Laid-Open Publication No. H11-157, a persistent antifogging agent comprising a hydrolyzable organosilicon compound, a silicic acid solution, a water-soluble resin and cyclodextrin is proposed.

However, in the above-mentioned method of applying a surfactant or a hydrophilic polymer to the surface of a substrate, the surfactant or the hydrophilic polymer is used during use, even if the initial antifogging property is good. And the like were washed away, so no sustained effect was obtained. The above-mentioned JP-A-58-32664 and JP-A-55-32664 are also referred to.
In the methods described in JP-A-99987 and JP-A-7-150072, the durability of the antifogging effect of the coating film (in the present invention, the property that the period during which the antifogging effect can be obtained without reprocessing after coating is long) is In the present invention, durability such as water resistance (meaning that a treatment agent for improving water wettability does not flow out) and scratch resistance were insufficient.

[0005] As described above, in general, a component having high hydrophilicity but poor scratch resistance and a component having high scratch resistance but low hydrophilicity are mixed to prepare a material having the advantages of both components. Also, hydrophilicity or scratch resistance, which is the advantage of a single component,
Each component was diluted by mixing, and therefore, only those having poor practicality were often obtained. Also, in general, components having high hydrophilicity but poor scratch resistance and components having high scratch resistance but poor hydrophilicity have different physical properties, and therefore, when mixed, they are cured due to poor compatibility. In many cases, the problem of opacity of objects was a problem.

[0006]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a film having excellent transparency, continuous prevention of fogging, water resistance,
An object of the present invention is to provide a hydrophilic coating resin composition having excellent scratch resistance and durability.

[0007]

The above object is achieved by the present invention, a resin composition for a hydrophilic coating comprising the following components A and B: A resin having in its molecule a hydrophilic portion composed of one or more alkali metal salts of an acid selected from the group consisting of sulfonic acid, phosphoric acid, and carboxylic acid; A three-dimensional structure of silicon dioxide or a precursor that provides the three-dimensional structure of silicon dioxide.

[0008] Further, the above A and B components are at the molecular level.
A hydrophilic coating resin composition which is compatibilized on the order of nanometer level, and further provides a contact angle with water of 15 ° or less after curing of the coating film and / or a pencil hardness of 8H or more. It is a resin composition for functional coating. Furthermore, the present invention provides a hydrophilic coating resin composition wherein the alkali metal salt is one or more selected from the group consisting of a sodium salt, a potassium salt, and a lithium salt, and particularly a lithium salt. The present invention further provides a hydrophilic coating resin composition wherein the acid is sulfonic acid. Furthermore, the present invention provides a hydrophilic coating resin composition wherein the reaction when the precursor becomes a three-dimensional structure of silicon dioxide is hydrolysis, and wherein the precursor is tetraethoxysilane. Provided is a resin composition for use.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION As a result of intensive studies, the present inventors have found that a specific hydrophilic component (A) and a scratch-resistant component (B) are combined by compatibilizing or the like. Thus, the above-mentioned problems could be solved.

The resin having an alkali metal salt of a sulfonic acid group, a phosphoric acid group or a carboxylic acid group in the molecule of the component A in the present invention includes, for example, sodium styrenesulfonate, potassium styrenesulfonate and styrenesulfonic acid. Lithium, sodium vinyl sulfonate, potassium vinyl sulfonate, lithium vinyl sulfonate, sodium allyl sulfonate, potassium allyl sulfonate, lithium allyl sulfonate, sodium methallylsulfonate, potassium methallylsulfonate, lithium methallylsulfonate, (Meth) acrylic acid-2-sulfoethyl ester sodium salt, (meth) acrylic acid-2-sulfoethyl ester potassium salt, (meth) acrylic acid-2-sulfoethyl ester lithium salt, 2-acrylamide-
2-methylpropanesulfonic acid sodium salt, 2-acrylamido-2-methylpropanesulfonic acid potassium salt, 2-acrylamido-2-methylpropanesulfonic acid lithium salt, mono (2-methacryloyloxyethyl) acid phosphate sodium salt, mono ( 2- (methacryloyloxyethyl) acid phosphate potassium salt, mono (2-methacryloyloxyethyl) acid phosphate lithium salt, vinylphosphonic acid sodium salt, vinylphosphonic acid potassium salt, vinylphosphonic acid lithium salt, sodium acrylate, acrylic Potassium acrylate, lithium acrylate, sodium methacrylate, potassium methacrylate, lithium methacrylate, sodium maleate, potassium maleate, male Lithium phosphate, sodium itaconate, potassium itaconate, which are polymers or copolymers of these monomers, such as lithium itaconic acid.

Any of the above-mentioned monomers can provide the desired performance as long as they are alkali metal salts.
A sodium salt, a potassium salt, and a lithium salt are preferable, and among them, a lithium salt is remarkably excellent in water resistance and is particularly preferable.
Although the reason for this is not clear, it can be inferred that the hydrophilic resin is easily incorporated into the three-dimensional structure of silicon dioxide due to the small radius of the lithium atom, and is hardly dissolved in water.

As the acid group that imparts hydrophilicity to the resin, a sulfonic acid group, a phosphoric acid group, and a carboxylic acid group can be used. Among them, a sulfonic acid group is preferable because of the degree of hydrophilicity imparted. Groups are particularly preferred. Sulfonic acid group,
Groups other than the phosphoric acid group and the carboxylic acid group cannot impart sufficient hydrophilicity.

The component A in the present invention can also be a copolymer of the above-mentioned monomer, an acid alkali metal salt, with a base acid. Further, it may be a copolymer with another polymerizable monomer as long as hydrophilicity is not impaired. Examples of the other copolymerizable monomers include acrylamide, methacrylamide, amide monomers such as dimethylacrylamide, vinyl alcohol, hydroxylalkyl acrylate, hydroxyl group-containing monomers such as hydroxylalkyl methacrylate, vinyl trialkoxysilane, Examples include a hydrolyzable silicon group-containing monomer such as γ- (meth) acryloxypropyl trialkoxysilane, and a crosslinkable monomer such as methylenebisacrylamide and methylenebismethacrylamide. Further, the component A may be a modified polymer to which a sulfonic acid group, a phosphoric acid group, a carboxylic acid group and a salt thereof are added after the polymer is formed, for example, by sulfoalkylating a hydroxyl group of polyvinyl alcohol with propane sultone or the like. it can.

The component A is a component mainly for imparting antifogging property and hydrophilicity to the coating film. The component A is used as a polymer to prevent dissolution in water from the coating film in consideration of water resistance, and has a molecular weight of 1,000 to 5.0.
It is preferably 00,000. Even if a monomer such as low molecular weight sulfonate, phosphate, carboxylate such as sodium p-toluenesulfonate, sodium methylphosphonate, sodium acetate and the like is used in combination with the component B of the present invention, the surface is prevented. No haze can be imparted. When an alkali metal salt having surface activity is used in combination with the component B of the present invention, the surface hydrophilicity at the initial stage may be excellent, but the water resistance is poor and the effect is lost in a short time. I will. However, when the component A of the present invention is used together with the component B, it not only gives the initial hydrophilicity but also its effect lasts for a long time.

The precursor for providing the three-dimensional structure of silicon dioxide used as the component B of the present invention includes hydrolysis,
Substantially gives a three-dimensional crosslinked structure of silicon dioxide through a curing process such as polycondensation, and specifically, tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetrabutoxysilane, methylsilicate, ethyl Silicate. These compounds can be used alone or in combination of two or more.

The three-dimensional structure of silicon dioxide used as the component B in the present invention includes a compound formed by hydrolyzing and / or heating one or more of the above precursors. These hydrolysis methods include general methods, for example, a sol-gel method, an inorganic acid such as hydrochloric acid, an organic acid such as acetic acid, an alkali or ammonia such as sodium hydroxide as a catalyst, or water alone. A method of performing decomposition can be used. By using a three-dimensional structure of silicon dioxide, it is possible to obtain a composition that is more excellent than in the case where the precursor is used as it is. The B component is a component for mainly providing surface hardness, scratch resistance, water resistance, durability, and the like. Furthermore, when the B component of the present invention is hydrolyzed and polycondensed to form a three-dimensional structure, no hydrophobic organic groups such as an alkyl group and a phenyl group remain, which has an adverse effect on antifogging properties and hydrophilicity. There is a feature that does not affect.

In order to obtain the composition of the present invention from the above components, for example, a method of mixing the components A and B, a method of mixing and polymerizing the components A and B (precursor), or a method of mixing the components B and B
For example, a method of mixing the A component into the (three-dimensional structure) component by press-fitting or the like can be used. Further, the B (precursor) component can be hydrolyzed in a solution in which the A component is dissolved by a sol-gel method. According to this method, both components A and B can be solubilized on the order of molecular level and nanometer level, which is preferable. For example, lithium polystyrene sulfonate can be dissolved in a mixed solution of water and ethanol, tetraethoxysilane can be added, and hydrolysis can be performed using an acid catalyst. In this way, even in the case of the combination of the component A and the component B, which has conventionally been difficult to compatibilize, it is possible to satisfactorily compatibilize at the molecular level, that is, to form a so-called hybrid. When hybridized, a transparent and homogeneous composition is obtained, and in the present invention, a hybrid is considered to be transparent.

The coating film obtained by the composition of the present invention comprises:
The antifogging property itself is sufficiently practical.
By performing the heat treatment at a temperature of 00 ° C. to 250 ° C., it is possible to form a coating film with further improved anti-fogging property, hardness, scratch resistance, water resistance, durability and the like. The ratio of the A component and the B component of the present invention should be determined by the required properties such as transparency, antifogging property, surface hardness, scratch resistance and water resistance, and durability thereof. The B component is used in the range of 20 to 2,000 parts by weight based on the weight of SiO _{2 based} on parts by weight. Here, the weight of SiO ₂ of the B component means that the B component is hydrolyzed and further polycondensed to form SiO _2.
It means the weight when it becomes. When the amount of the component B is less than 20 parts by weight, transparency, surface hardness, scratch resistance, water resistance and durability thereof are reduced. When the amount of the component B is more than 2000 parts by weight, hydrophilicity and anti-fogging property are reduced. More preferably 30
１０００1000 parts by weight.

The composition of the present invention can further contain a solvent, various additives and the like in addition to the above-mentioned essential components. As the solvent, water or methanol, ethanol,
Isopropanol is preferably used. In addition, alcohols, ketones such as acetone and 2-butanone, esters such as ethyl acetate, dimethylformamide, dimethylacetamide, dimethylsulfoxide and the like can be used in combination. As additives, anionic or nonionic surfactants, various water-soluble resins or water-dispersible resins, water-soluble salts, colloidal silica, fine particle fillers such as colloidal alumina, viscosity modifiers, pigments, dyes And so on. If necessary, an aluminum chelate compound, a tin compound or the like can be used as a silanol condensation catalyst.

An organic silicon compound such as a silane coupling agent can be added in order to improve the adhesiveness of the coating within a range that does not impair the hydrophilicity. Specific examples include methyltrialkoxysilane, ethyltrialkoxysilane, phenyltrialkoxysilane, methyltrichlorosilane, vinyltrichlorosilane, vinyltrialkoxysilane, γ-aminopropyltrialkoxysilane, γ-glycidoxypropyltrisilane. Examples include alkoxysilane and γ-methacryloxypropyl trialkoxysilane. Further, a metal alkoxide other than silicon may be included as another component of the present invention for the purpose of adjusting the coating film performance.

The composition of the present invention can be applied to various substrates, and the solution is usually applied to the substrate before use. As the substrate in this case, the material to which the antifogging property or hydrophilicity of the present invention can be applied is not particularly limited, and examples thereof include inorganic glass, plastic, ceramic, metal, mirror material, and building material. Are preferably used for window glasses, window glasses of automobiles, trains, etc., plastic lenses, inorganic glass lenses, mirrors of bathrooms, mirrors of automobiles, and inner and outer walls of buildings.

The method of applying the composition of the present invention to a substrate is generally known, for example, by brushing, dip coating, spin coating, bar coating, flow coating, spray coating, roll coating, air knife coating, blade coating, and the like. Various methods used can be used. As described above, the resin composition for hydrophilic coating of the present invention is characterized in that it is excellent in hydrophilicity, excellent anti-fog property, and extremely excellent in transparency, hardness, scratch resistance, water resistance and durability. . Considering the reason why the resin composition for hydrophilic coating of the present invention has the above-mentioned excellent performance, as components for expressing hydrophilicity (anti-fog property), high molecular weight sulfonic acid, phosphoric acid, and carboxylic acid are used. The use of alkali metal salts, the use of silicon compounds such as tetraethoxysilane, which do not leave any organic components upon curing, in order to obtain the hardness and scratch resistance of the coating film without deteriorating the hydrophilicity. Hybridization at the molecular or nano level gives a hydrophilic functional group to the surface and without deteriorating its performance, excellent hydrophilicity, persistent antifogging, transparency, scratch resistance, water resistance, durability It is estimated that the property was obtained.

[0023]

EXAMPLES The test method of the performance test performed in the following examples is as follows. The test pieces obtained in each example were tested for the following items (a) to (d). (B) Transparency Transparency and the presence or absence of coating unevenness were examined by visual observation. (B) Scratch resistance (surface hardness) The surface hardness was represented by pencil hardness according to JIS K-5400 (8.4) pencil scratch test. (C) Anti-fogging property 1 (contact angle) The contact angle of water on the coating film surface was measured. It can be determined that the smaller the numerical value, the better the antifogging property. Anti-fogging property 2 The test piece was allowed to stand on a beaker containing hot water kept at 90 ° C. with the coated surface facing down, and the test piece was visually observed for fogging. (D) Water resistance After the test piece was left in water at room temperature for 24 hours and allowed to dry naturally, the surface hardness, hydrophilicity and antifogging property were tested by the above method, and compared with those not left in water. did.

Example 1 (1) Preparation of coating solution 1.0 g of sodium polystyrene sulfonate was added to 75 g of water
Was dissolved. To this was added 58 g of ethanol. After further adding 17.4 g of tetraethoxysilane, the solution was adjusted to pH 3 by adding about 1 g of 2N hydrochloric acid and stirred at room temperature for 1 hour to hydrolyze tetraethoxysilane.
A three-dimensional structure of silicon dioxide was constructed. In this way,
A resin composition (E-1) for a hydrophilic coating of the present invention was obtained. (2) Preparation of test piece (E-1) was applied on a glass plate using a bar coater so that the film thickness after drying was about 1 μm, and then 150 ° C.
For 30 minutes to obtain a test piece. (3) Performance test The above test was performed. Table 1 shows the results.

Example 2 (1) Preparation of coating liquid 1.0 g of polymono (2-methacryloyloxyethyl) acid phosphate sodium salt was dissolved in 75 g of water. To this was added 58 g of ethanol. After adding 17.4 g of tetraethoxysilane, about 1 g of 2N hydrochloric acid was added.
In addition, the solution was adjusted to pH 3 to hydrolyze tetraethoxysilane, and the solution was stirred at room temperature for 1 hour to obtain a hydrophilic coating resin composition (2) of the present invention. (2) Preparation of test piece (E-2) was applied on a glass plate using a bar coater so that the film thickness after drying was about 1 μm, and then 150 ° C.
For 30 minutes to obtain a test piece. (3) Performance test The above test was performed. Table 1 shows the results.

Example 3 (1) Preparation of coating liquid 1.0 g of sodium polyacrylate was dissolved in 75 g of water. To this was added 58 g of ethanol. After adding 17.4 g of tetraethoxysilane, about 1 g of 2N hydrochloric acid was added.
Was added to adjust the solution to pH 3, and tetraethoxysilane was hydrolyzed. This solution was stirred at room temperature for 1 hour to give the hydrophilic coating resin composition (E-
3) was obtained. (2) Preparation of test piece (E-3) was applied on a glass plate using a bar coater so that the film thickness after drying was about 1 μm, and then 150 ° C.
For 30 minutes to obtain a test piece. (3) Performance test The above test was performed. Table 1 shows the results.

Example 4 (1) Preparation of coating solution 1.0 g of potassium polystyrene sulfonate was dissolved in 75 g of water. To this was added 58 g of ethanol. Further, 17.4 g of tetraethoxysilane was added, and then about 1 g of 2N hydrochloric acid was added to adjust the solution to pH 3 to hydrolyze tetraethoxysilane. This solution was stirred at room temperature for 1 hour to obtain the hydrophilic coating resin composition (E-4) of the present invention. (2) Preparation of test piece (E-4) was applied on a glass plate using a bar coater so that the film thickness after drying was about 1 μm, and then 150 ° C.
For 30 minutes to obtain a test piece. (3) Performance test The above test was performed. Table 1 shows the results.

Example 5 (1) Preparation of coating liquid 1.0 g of lithium polystyrene sulfonate was dissolved in 75 g of water. To this was added 58 g of ethanol. Further, 17.4 g of tetraethoxysilane was added, and then about 1 g of 2N hydrochloric acid was added to adjust the solution to pH 3 to hydrolyze tetraethoxysilane. This solution was stirred at room temperature for 1 hour to obtain a hydrophilic coating resin composition (E-5) of the present invention. (2) Preparation of test piece (E-5) was applied on a glass plate using a bar coater so that the film thickness after drying was about 1 μm, and then 150 ° C.
For 30 minutes to obtain a test piece. (3) Performance test The above test was performed. Table 1 shows the results.

Example 6 (1) Preparation of coating solution 1.0 g of lithium polymono (2-methacryloyloxyethyl) acid phosphate was dissolved in 75 g of water. To this was added 58 g of ethanol. Further, 17.4 g of tetraethoxysilane was added, and then about 1 g of 2N hydrochloric acid was added to adjust the solution to pH 3 to hydrolyze tetraethoxysilane. This solution was stirred at room temperature for 1 hour to obtain the hydrophilic coating resin composition (E-
6) was obtained. (2) Preparation of test piece (E-6) was applied on a glass plate using a bar coater so that the film thickness after drying was about 1 μm, and then 150 ° C.
For 30 minutes to obtain a test piece. (3) Performance test The above test was performed. Table 1 shows the results.

Example 7 (1) Preparation of coating liquid 1.0 g of lithium polyacrylate was dissolved in 75 g of water. To this was added 58 g of ethanol. Further, 17.4 g of tetraethoxysilane was added, and then about 1 g of 2N hydrochloric acid was added to adjust the solution to pH 3 to hydrolyze tetraethoxysilane. This solution was stirred at room temperature for 1 hour to obtain the hydrophilic coating resin composition (E-
7) was obtained. (2) Preparation of test piece (E-7) was applied on a glass plate using a bar coater so that the film thickness after drying was about 1 μm, and then 150 ° C.
For 30 minutes to obtain a test piece. (3) Performance test The above test was performed. Table 1 shows the results.

Example 8 (1) Preparation of coating solution 1.0 g of lithium polystyrene sulfonate was dissolved in 75 g of water. To this was added 58 g of ethanol. Further, 17.4 g of tetraethoxysilane was added, and then about 1 g of 2N hydrochloric acid was added to adjust the solution to pH 3 to hydrolyze tetraethoxysilane. This solution was stirred at room temperature for 1 hour to obtain the hydrophilic coating resin composition (E-8) of the present invention. (2) Preparation of test piece (E-8) was applied on a glass plate using a bar coater so that the film thickness after drying was about 1 μm, and was left to dry at room temperature for 3 hours to obtain a test piece. . (3) Performance test The above test was performed. Table 1 shows the results.

Example 9 (1) Preparation of coating liquid 0.5 g of lithium polystyrene sulfonate was added to 141 g of water
Was dissolved. To this was added 110 g of ethanol. After adding 34.7 g of tetraethoxysilane, 2N
About 1 g of hydrochloric acid was added to adjust the solution to pH 3, and tetraethoxysilane was hydrolyzed. This solution is added at room temperature for 1 hour.
After stirring for an hour, a hydrophilic coating resin composition (E-9) of the present invention was obtained. (2) Preparation of test piece (E-9) was applied on a glass plate using a bar coater so that the film thickness after drying was about 1 μm, and then 150 ° C.
For 30 minutes to obtain a test piece. (3) Performance test The above test was performed. Table 1 shows the results.

Example 10 (1) Preparation of coating liquid 10.0 g of lithium polystyrene sulfonate was added to water 169
g. To this, 131 g of ethanol was added.
After adding 8.7 g of tetraethoxysilane, 2N
About 1 g of hydrochloric acid was added to adjust the solution to pH 3, and tetraethoxysilane was hydrolyzed. This solution is added at room temperature for 1 hour.
After stirring for an hour, a resin composition for hydrophilic coating (E-10) of the present invention was obtained. (2) Preparation of test piece (E-10) was applied on a glass plate using a bar coater so that the film thickness after drying was about 1 μm, and then 150 μm.
A test piece was obtained by heating and curing at 30 ° C. for 30 minutes. (3) Performance test The above test was performed. Table 1 shows the results.

Example 11 (1) Preparation of Coating Solution 1.0 g of lithium polystyrene sulfonate was dissolved in 75 g of water. To this was added 58 g of ethanol. Further, after adding 12.7 g of tetramethoxysilane, about 1 g of 2N hydrochloric acid was added to adjust the solution to pH 3, and hydrolysis of tetramethoxysilane was performed. This solution was stirred at room temperature for 1 hour to obtain a hydrophilic coating resin composition (E-11) of the present invention. (2) Preparation of test piece (E-11) was applied on a glass plate using a bar coater so that the film thickness after drying was about 1 μm, and then 150 μm.
A test piece was obtained by heating and curing at 30 ° C. for 30 minutes. (3) Performance test The above test was performed. Table 1 shows the results.

Example 12 (1) Preparation of coating liquid 0.5 g of lithium polystyrene sulfonate was added to 141 g of water
Was dissolved. To this was added 110 g of ethanol. After adding 25.4 g of tetraethoxysilane, 2N
About 1 g of hydrochloric acid was added to adjust the solution to pH 3, and tetraethoxysilane was hydrolyzed. This solution is added at room temperature for 1 hour.
After stirring for an hour, a hydrophilic coating resin composition (E-12) of the present invention was obtained. (2) Preparation of test piece (E-12) was applied on a glass plate using a bar coater so that the film thickness after drying would be about 1 μm, and then 150 μm.
A test piece was obtained by heating and curing at 30 ° C. for 30 minutes. (3) Performance test The above test was performed. Table 1 shows the results.

Example 13 (1) Preparation of coating liquid 10.0 g of lithium polystyrene sulfonate was added to water 169
g. To this, 131 g of ethanol was added.
After adding 6.3 g of tetraethoxysilane, 2N
About 1 g of hydrochloric acid was added to adjust the solution to pH 3, and tetraethoxysilane was hydrolyzed. This solution is added at room temperature for 1 hour.
After stirring for an hour, a resin composition (E-13) for hydrophilic coating of the present invention was obtained. (2) Preparation of test piece (E-13) was applied on a glass plate using a bar coater so that the film thickness after drying would be about 1 μm, and then 150 μm.
A test piece was obtained by heating and curing at 30 ° C. for 30 minutes. (3) Performance test The above test was performed. Table 1 shows the results.

Comparative Example 1 (1) Preparation of Coating Solution 1.0 g of lithium polystyrene sulfonate was dissolved in 14 g of water. 10 g of ethanol was added thereto to obtain a coating liquid (C-1). (2) Preparation of test piece (C-1) was applied on a glass plate using a bar coater so that the film thickness after drying was about 1 μm, and then 150 ° C.
For 30 minutes to obtain a test piece. (3) Performance test The above test was performed. Table 1 shows the results.

Comparative Example 2 (1) Preparation of Coating Solution Tetraethoxysilane 1 was added to 61 g of water and 47 g of ethanol.
7.4 g were added. Add about 1 g of 2N hydrochloric acid to pH
The mixture was adjusted to 3 to hydrolyze tetraethoxysilane. This solution was stirred at room temperature for 1 hour to obtain a coating liquid (C-2). (2) Preparation of test piece (C-2) was applied on a glass plate using a bar coater so that the film thickness after drying was about 1 μm, and then 150 ° C.
For 30 minutes to obtain a test piece. (3) Performance test The above test was performed. Table 1 shows the results.

Comparative Example 3 (1) Preparation of Coating Solution 1.0 g of α-cyclodextrin was dissolved in 75 g of water. To this was added 58 g of ethanol. Further, 17.4 g of tetraethoxysilane was added, and then about 1 g of 2N hydrochloric acid was added to adjust the solution to pH 3 to hydrolyze tetraethoxysilane. This solution was stirred at room temperature for 1 hour to obtain a coating resin composition (C-3). (2) Preparation of test piece (C-3) was applied on a glass plate using a bar coater so that the film thickness after drying was about 1 μm, and then 150 ° C.
For 30 minutes to obtain a test piece. (3) Performance test The above test was performed. Table 1 shows the results.

Comparative Example 4 (1) Preparation of Coating Solution 1.0 g of polyethylene glycol was dissolved in 75 g of water. To this was added 58 g of ethanol. Further, 17.4 g of tetraethoxysilane was added, and then about 1 g of 2N hydrochloric acid was added to adjust the solution to pH 3 to hydrolyze tetraethoxysilane. This solution was stirred at room temperature for 1 hour to obtain a coating resin composition (C-4). (2) Preparation of test piece (C-4) was applied on a glass plate using a bar coater so that the film thickness after drying was about 1 μm, and further 150 ° C.
For 30 minutes to obtain a test piece. (3) Performance test The above test was performed. Table 1 shows the results.

Comparative Example 5 (1) Preparation of Coating Solution 1.0 g of sodium p-toluenesulfonate was added to 75 g of water.
Was dissolved. To this was added 58 g of ethanol. Further, 17.4 g of tetraethoxysilane was added, and then about 1 g of 2N hydrochloric acid was added to adjust the solution to pH 3 to hydrolyze tetraethoxysilane. This solution was stirred at room temperature for 1 hour to obtain a coating resin composition (C-5). (2) Preparation of test piece (C-5) was applied on a glass plate using a bar coater so that the film thickness after drying was about 1 μm, and then 150 ° C.
For 30 minutes to obtain a test piece. (3) Performance test The above test was performed. Table 1 shows the results.

Comparative Example 6 (1) Preparation of Coating Solution 1.0 g of bis (2-ethylhexyl) sulfosuccinate sodium salt as a surfactant was dissolved in 75 g of water. To this was added 58 g of ethanol. After adding 17.4 g of tetraethoxysilane, about 1 g of 2N hydrochloric acid was added.
Was added to adjust the solution to pH 3, and tetraethoxysilane was hydrolyzed. This solution was stirred at room temperature for 1 hour to obtain a coating resin composition (C-6). (2) Preparation of test piece (C-6) was applied on a glass plate using a bar coater so that the film thickness after drying was about 1 μm, and then 150 ° C.
For 30 minutes to obtain a test piece. (3) Performance test The above test was performed. Table 1 shows the results.

Comparative Example 7 (1) Preparation of Coating Solution 1.0 g of lithium polystyrene sulfonate was dissolved in 75 g of water. To this was added 58 g of ethanol. After adding 13.3 g of methyltriethoxysilane, 2N
The solution was adjusted to pH 3 by adding about 1 g of hydrochloric acid. This solution was stirred at room temperature for 1 hour to obtain a coating resin composition (C-7). (2) Preparation of test piece (C-7) was applied on a glass plate using a bar coater so that the film thickness after drying was about 1 μm, and then 150 ° C.
For 30 minutes to obtain a test piece. (3) Performance test The above test was performed. Table 1 shows the results.

[0044]

[Table 1]

[0045]

Industrial Applicability According to the present invention, there is provided a hydrophilic coating resin composition having excellent transparency, continuously preventing fogging, and having excellent durability, water resistance and scratch resistance.

Claims (9)

[Claims] 1. A resin composition for hydrophilic coating comprising the following components A and B: (A) one or more acids selected from the group consisting of sulfonic acids, phosphoric acids and carboxylic acids; (B) a three-dimensional structure of silicon dioxide or a precursor that provides the three-dimensional structure of silicon dioxide. 2. A hydrophilic coating resin composition obtained by compatibilizing the components A and B according to claim 1 on the order of molecular level and nanometer level. 3. The resin composition for a hydrophilic coating according to claim 1, which gives a contact angle with water of 15 ° or less after curing the coating film. 4. The resin composition for hydrophilic coating according to claim 1, wherein a pencil hardness of 8H or more is provided after the coating film is cured. 5. The hydrophilic coating according to claim 1, wherein the alkali metal salt is at least one member selected from the group consisting of a sodium salt, a potassium salt, and a lithium salt. Resin composition. 6. The resin composition for hydrophilic coating according to claim 1, wherein the alkali metal salt is a lithium salt. 7. The resin composition for a hydrophilic coating according to claim 1, wherein the acid is a sulfonic acid. 8. The resin composition for hydrophilic coating according to claim 1, wherein the reaction when the precursor becomes a three-dimensional structure of silicon dioxide is hydrolysis. 9. The resin composition for hydrophilic coating according to claim 1, wherein the precursor is tetraethoxysilane.