JP2001152137A - Non-fogging film-formed base and its preparation process - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a non-fogging coated film which is excellent is fog resistance, water-wiping resistance and wear resistance and retains its non-fogging performance over a long time. SOLUTION: On the surface of a base, a water-absorbing organic-inorganic composite coated film comprising a water-absorbing organic polymer and silica, is applied. Subsequently, the surface is subjected to a water-repellent treatment such as the formation of a water-repellent coated film.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to
The present invention relates to a base material provided with an antifogging film used in various fields such as window materials for automobiles and mirrors, and a method for producing the same.

[0002]

2. Description of the Related Art Recently, a film having a photocatalytic function has been formed on the surface of a substrate in order to impart hydrophilicity and anti-fog properties to the substrate. For example, Japanese Patent Application Laid-Open No. 5-253544
Plate member in which a part of the photocatalyst fine powder mainly composed of anatase type titania described in Japanese Patent Application Laid-Open No. H07-230080 is exposed from the surface of the binder layer, and the photocatalyst fine particles described in Japanese Patent Application Laid-Open No. , Strontium titanate, iron oxide, tungsten oxide, iron titanate, bismuth oxide, tin oxide, etc., and the gap filling particles of the photocatalytic particles are tin, titanium, silver, copper, zinc, iron, platinum, cobalt,
A multifunctional material having a photocatalytic function, which is a metal or oxide of nickel, covered with a hydrophilic coating containing titania particles having a photocatalytic average crystal particle size of about 0.1 μm or less described in JP-A-9-59042. Transparent substrates and the like are known.

[0003] It has long been known that a surfactant is applied to the surface of a substrate to modify the surface to have hydrophilicity and anti-fogging properties. For example, Japanese Patent Application Laid-Open No. 52-101680 discloses this. Describes that the addition of a water-soluble organic polymer such as polyacrylic acid or polyvinyl alcohol to a surfactant increases the durability of hydrophilicity and antifogging property.

Further, Japanese Patent Publication No. 5-67330 discloses that a porous film made of a hydrophobic polymer is coated on the surface and inside thereof with a film of a copolymer of polyvinyl alcohol and vinyl acetate to form cellulose, glycols and glycerin. A method for immobilizing a hydrophilic polymer in a film is described.

JP-A-10-212471 discloses an antifogging agent comprising polyvinyl alcohol, which is an organic substance having a hydroxyl group, tetramethoxysilane, which is a metal organic compound, and hydrochloric acid, which is a catalyst for condensation polymerization of these compounds. Is disclosed.

JP-A-11-84102 discloses an antifogging coating having a water-absorbing film and a porous film from the side closer to the surface of a substrate.

Further, in the physical method, a hydrophilic treatment such as a plasma treatment or a laser irradiation treatment has been put to practical use. Generally, it is effective in a short time after the treatment, but there is a problem in sustainability.

[0008]

SUMMARY OF THE INVENTION The above-mentioned JP-A-5-25
In hydrophilic and anti-fog films utilizing a photocatalytic function as disclosed in JP-A No. 3544, JP-A-7-23280, JP-A-9-59042, etc., it is essential to be exposed to ultraviolet rays. Illuminance is several mW /
It is necessary to irradiate ultraviolet rays of cm2 for several hours,
When ultraviolet light is not applied, not only antifogging property but also hydrophilic property is not exhibited. Also, once exposed to ultraviolet light, once it becomes hydrophilic and antifogging, its performance can be maintained for a short time,
After a few hours the effect is lost. Furthermore, the contact angle of water is 1
It becomes hydrophilic at around 0 # or less, but the antifogging property does not appear unless it is reduced to around 5 # or less. When a photocatalytic film is coated on a substrate, titania having a photocatalytic film function is a high-refractive-index film, so that the reflectivity may be increased or colored, thereby impairing the design.

Further, the organic polymer film described in Japanese Patent Application Laid-Open No. 52-101680 is not practically sufficient for some applications because of its low water resistance and low mechanical strength.

Further, a method described in Japanese Patent Publication No. 5-67330, in which a film of cellulose or the like is fixed on the surface and inside of a porous film via a film of a copolymer of polyvinyl alcohol and vinyl acetate. In addition, the coating is extremely soft, and it is difficult to expect chemical durability, so that its use is limited.

The membranes described in JP-A-10-212471 and JP-A-11-84102 are excellent in antifogging performance because the water-absorbing polymer is exposed to the surface. Insufficient abrasion resistance during drying is not enough.Especially, the abrasion resistance in a hygroscopic state is remarkably reduced, the film swells, and it is difficult to use it for daily wiping. If a curable additive such as a system polymer is added, the antifogging performance is inferior, so that good scratch resistance and antifogging property cannot be obtained at the same time.

Furthermore, a coating made of an inorganic substance has a relatively high film strength, but a substance exhibiting anti-fogging properties has a high solubility in water and the coating may easily disappear.
The hydrophilicity due to physical treatment can also maintain its effect only for a short period of time, and its use is practically limited.

These methods described above only provide hydrophilicity and anti-fogging property temporarily or for a relatively short period of time, and it is difficult to expect sufficient durability of the effect. However, the water film is difficult to be uniform, so that the perspective image and the reflection image are distorted, and it is difficult to say that the film has hydrophilicity but does not have antifogging properties, and that it is difficult to adopt it in practical use.

[0014]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has been made by forming a water-absorbing organic-inorganic composite coating on the surface of a substrate and further forming a water-repellent coating as a protective film. By forming a two-layer structure, a highly durable anti-fogging film-forming substrate having no image distortion and having excellent transparency and without impairing the color tone of the substrate and capable of maintaining performance for a long period of time, and its It is intended to provide a manufacturing method.

That is, the base material for forming an antifogging film of the present invention is obtained by coating the surface of a base material with a water-absorbing organic-inorganic composite film comprising a water-absorbing organic polymer and an inorganic substance, and subjecting the surface to water-repellent processing. It is characterized by.

The antifogging film-forming substrate of the present invention may be a water-absorbing organic-inorganic composite film comprising hydroxypropyl cellulose, polyvinyl alcohol, polyvinyl acetal,
It is characterized by comprising a water-absorbing organic polymer composed of at least one of polyvinylpyrrolidone and polyvinyl acetate, and an inorganic substance containing silica.

Further, the substrate for forming an antifogging film of the present invention comprises:
The composition of the water-absorbing organic-inorganic composite coating is such that the content of the organic polymer is 99.5 to 95 wt% and the content of the inorganic substance containing silica is 0.5 to 5.0 wt%.

Further, it is preferable that the substrate on which the antifogging film is formed of the present invention has a water repellent film formed thereon as a water repellent process.

Further, the water-repellent coating is made of a silicon compound, and at least one of the functional groups is a methyl group (-CH
_{In 3} ), the other functional group preferably comprises an isocyanate group (-NCO). .

The antifogging film-forming substrate of the present invention has a water-absorbing organic-inorganic composite film having a thickness of 2 to 10 μm.
The thickness of the water-repellent coating is 10 nm or less.

In the method for producing a substrate having an antifogging film according to the present invention, a solution in which a water-absorbing organic polymer and a silicate compound are uniformly dissolved in a mixed solvent of lower alcohol and water is applied to the surface of the substrate. A primary drying process is performed later, and a secondary drying process is performed after a water-repellent film as a protective film is applied thereon.

The first drying treatment is performed at 90 to 15 times.
0 ° C. and / or a second drying treatment at 70 ° C.
It is preferably performed at a temperature of up to 120 ° C.

[0023]

The substrate on which the water-absorbing organic-inorganic composite coating is formed is
The water-absorbing organic polymer inherently provides anti-fogging properties. Until the water absorbing ability (saturated state) of the organic polymer is exceeded, water droplets do not adhere to the surface and the anti-fogging property is exhibited. Since a uniform water film is formed, the antifogging property can be maintained semipermanently. However, use of a coating made of a water-absorbing organic polymer alone does not provide water resistance or mechanical strength, and cannot be expected to have chemical durability, so that its use is greatly limited. Therefore, in the present invention, by using an organic-inorganic composite coating as the water-absorbing coating, the water resistance and the chemical durability are improved, and the adhesion to the substrate is remarkably improved. Further, as a water-repellent treatment on the surface, for example, by forming a water-repellent protective film on the upper layer, the free energy of the surface is reduced (dynamic friction coefficient is greatly reduced), and the wear strength is greatly improved. be able to. Furthermore, the water-repellent film has an extremely thin film thickness (monomolecular level) of 10 nm or less and does not have a dense structure because only a drying process is performed. Without impairing the performance (adsorption and desorption of water), the function can be used much more effectively, so that it exhibits excellent antifogging properties over a long period of time.

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The antifogging film-forming substrate of the present invention comprises:
For example, after a solution obtained by uniformly dissolving a water-absorbing organic polymer and a silicate compound in a mixed solvent of lower alcohol and water is applied to the substrate surface, a first drying treatment is performed to form a water-absorbing organic-inorganic composite coating. It can be manufactured by applying a water-repellent film as a protective film thereon and then performing a second drying treatment.

By the above-mentioned drying, the water-absorbing organic-inorganic composite coating has a composite structure in which the silicate compound becomes amorphous silica and exists as a matrix so as to surround the water-absorbing polymer. With this composite structure, the mechanical strength, chemical durability, water resistance, and the like of the coating can be improved. On the other hand, the water-repellent coating has a film thickness of 10 nm or less, is extremely thin (monomolecular level), and does not have a dense structure because only drying treatment is performed. Without impairing the performance (adsorption and desorption of moisture) of the water-soluble organic-inorganic composite coating, it is possible to particularly improve the abrasion strength and exhibit excellent antifogging properties over a long period of time.

The composition range of the water-absorbing organic-inorganic composite film of the present invention is such that the content of the water-absorbing organic polymer is 99.5 to 95.
0 wt%, content of silica component is 0.5 to 5.0 wt%
It is preferred that 0.5w silica content
If it is less than t%, the water resistance and chemical durability of the water-absorbing organic polymer are insufficient, and if it exceeds 5.0 wt%, the water resistance and chemical durability are improved. And the antifogging performance decreases. More preferably, 1.0 to 2.
The range of 5wt% is good. The silica may be a single component of silica, or may contain titania, zirconia, alumina or the like in the silica.

The water-absorbing organic-inorganic composite film has a thickness of 2 to 2.
The range of 10 μm is preferable, and if it is less than 2 μm, the water absorbing ability is insufficient, and if it exceeds 10 μm, the moisture permeability (air permeability) decreases, and the release of the once adsorbed water becomes slow, and in some cases, it becomes cloudy. More preferably, it is in the range of 5 to 7 μm.

The present invention is characterized in that the surface of the water-absorbing inorganic-organic composite coating is subjected to a water-repellent treatment. The water-repellent treatment is preferably a water-repellent coating. Can have water repellency. The thickness of the protective film, which is a water-repellent coating, is preferably 10 nm or less. The antifogging property is not sufficiently exhibited, and it is difficult to exhibit antifogging properties.

As the organic polymer raw material for forming the water-absorbing organic-inorganic composite coating, there can be used hydroxypropylcellulose, polyvinyl alcohol, polyvinylpyrrolidone, polyvinyl acetal, polyvinyl acetate and the like.

Further, as a silica raw material as an inorganic substance, a silicic acid compound such as tetraethoxysilane, tetramethoxysilane, monomethyltriethoxysilane, monomethyltrimethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane and the like can be used. . As other components that can be contained in the silica, alumina, titania, zirconia, and the like can be used, and the respective raw materials may be alkoxides and acetylacetonates. In particular, zirconium may be zirconium chloride.

The raw material of the protective film exhibiting water repellency is not particularly limited as long as a water repellent film can be obtained. Preferably, at least one of the functional groups is a methyl group (-CH ₃ ) The functional group is an isocyanate group (-
NCO), for example, silyl isocyanate, fluoroalkyltrimethoxysilane, or fluoroalkyltrimethoxysilane is preferred.

As the diluting solvent, water and an alcohol-based solvent are preferred, and specific examples thereof include methanol,
Ethanol, propanol, ethylene glycol, propylene glycol, hexylene glycol, and further esters such as ethyl acetate, butyl acetate and amyl acetate;
Further, a suitable amount of a cellosolve such as methyl cellosolve, ethyl cellosolve, and butyl cellosolve and a solvent obtained by mixing them, and a suitable amount of a silane coupling agent such as methacryloxypropyltrimethoxysilane as a coupling agent and a methyl silicone such as dimethyl silicone as a leveling agent. May be added. Alcohols or cellosolves which are originally contained in the solution may be selected alone or in a mixture in consideration of the evaporation rate of the solution and the film viscosity.

The coating method is not particularly limited, but from the viewpoint of productivity and the like, for example, a spin coating method, a dip coating method, a reverse coating method, a flexographic printing method, and other roll coating methods. And a curtain coating method, and a nozzle coating method, a spray coating method, a screen printing method and the like can be appropriately employed. The concentration of the total solid content in the coating liquid when forming a coating film by these coating methods is about 1 to 5% by weight, and the viscosity of the coating liquid is 0.1%.
It is preferably about 002 to 0.01 N · s / m ² .

As the drying treatment after coating, the primary drying after the formation of the water-absorbing organic-inorganic mixed film is performed at a drying temperature of 90 to 1
The drying time is preferably about 10 to 30 minutes at about 50 ° C, more preferably the drying temperature is 110 to 130 ° C.
The drying time is about 15 to 20 minutes. The secondary drying after forming the protective film is performed at a drying temperature of 70 to
The drying time at about 120 ° C. is preferably about 5 to 30 minutes, and more preferably at a temperature of 100 to 110 ° C. for 15 to 20 minutes. Below the drying temperature, evaporation of the solvent is insufficient, water resistance, mechanical strength and chemical durability are insufficient, and no change in performance is observed even when the temperature is increased. .

As a substrate used in the present invention, glass is typically used, and the glass is a plate glass commonly used for automobiles, architectural and industrial glass, so-called float plate glass, and the like. It can be used as various types of colored glass such as clear, green, bronze, etc., various functional glass, tempered glass and similar glass, laminated glass, multi-layer glass, etc., as well as various flat glass products such as flat or bent plates. Needless to say. The thickness is, for example, about 1.0 mm or more and about 12 mm or less, and about 3.0 mm for architectural use.
The glass is preferably about 10 mm or more and about 10 mm or less, and is about 2.0 mm or more and about 5.0 mm or less for automobiles. In addition, the substrate of the present invention is not limited to glass, and other than glass, resins, metals, ceramics, and the like can be used as long as they do not deteriorate even after being dried in the above temperature range.

The physical properties relating to the anti-fogging property can be as long as the coating formed on the surface of the base material can adsorb as much water as possible. According to the present invention, the coating formed on the base material can maintain the anti-fogging property over a long period of time because the water-absorbing organic-inorganic mixed coating has a function of adsorbing and desorbing moisture through the surface protective film. That's why. In other words, the water-absorbing organic-inorganic mixed coating is
This is because moisture can be adsorbed by the entire film, and at the same time, in the dry state, the adsorbed moisture can be almost completely desorbed and desorbed.

The antifogging property is closely related to the water absorption. The antifogging property exhibits antifogging properties until the water absorbing ability of the water-absorbing organic polymer reaches a saturated state, and fogging occurs when the capacity exceeds the capacity. Water absorption refers to the property of a material to take in moisture.

[0038]

The present invention will be described below in detail with reference to examples. However, the present invention is not limited to these examples.

The antifogging property and the durability of the coating were evaluated by the following methods. Evaluation of antifogging property: in accordance with the test for anti-fog agent for glasses (JIS S 3040). Passed if there was no fogging even after exhalation after each test. Cool temperature evaluation: Left in a refrigerator at 4 ° C. for 30 minutes, then removed to room temperature and left for 10 minutes [Pass / Fail] Appearance while repeating the operation for 10 cycles A film which had no change and showed no fogging even after exhalation after each test was passed. Membrane strength evaluation: Robustness test Load; 100 g / cm ² cotton canvas; canvas cloth (JIS L 3120-1961-1206) Stroke speed; 1 reciprocation / sec Number of strokes: 3000 reciprocations [Pass / Fail Judgment] Water resistance was evaluated as being acceptable if no remarkable scratches were generated and no fogging occurred even when exhaled after the test. 5 ° C) for 6 hours [Pass / Fail] The film was evaluated as acceptable if there was no change in the appearance of the film and no fogging occurred even after exhalation after the test. Water wiping evaluation: Includes water in a commercial kitchen sponge. 2
00 reciprocal wiping [Pass / Fail judgment] A test piece was judged to have passed if there was no change in film appearance and no fogging even after exhalation after the test. Acid resistance evaluation: Immersion in 1 wt% HCl aqueous solution for 6 hours at room temperature [Pass / Fail judgment] Those having no change in appearance and having no fogging even when exhaled after the test were regarded as acceptable. The results of the above-mentioned performance evaluation in the following Examples are shown in Table 1.
Table 2 shows the performance evaluation results of the comparative example.

(Example 1) Preparation of a solution for a water-absorbing organic-inorganic mixed coating film: polyvinyl acetal (KX-1: manufactured by Sekisui Chemical) as a water-absorbing organic polymer raw material, and ethyl silicate (reagent) as a matrix-forming silica sol raw material : Kishida Chemical Co., Ltd.) and diluted with a mixed solvent of Echinen F-1 (Kishida Chemical Co.) and water (weight% is Echinen F-1: water = 5: 5) as a solvent,
The solid content was adjusted to 3 wt%. The procedure for preparing the solution was as follows.

Polyvinyl acetal: silica = 99.
5: 0.5% by weight, a predetermined amount of a solvent was added, and the mixture was stirred at room temperature to obtain a coating solution.

Preparation of Protective Film Solution: Methyl triisocyanate (SIC-
003: manufactured by Matsumoto Pharmaceutical Co., Ltd.) and diluted with ethyl acetate (reagent: manufactured by Kishida Chemical Co., Ltd.) to a solid content concentration of 1 wt%.

Film formation and drying of a water-absorbing organic-inorganic mixed film: Soda lime glass of 10 cm × 10 cm × 2 mm thick was used for the substrate, and the coated surface was sufficiently polished with cerium oxide, and then washed with tap water. After rinsing with ion-exchanged water and removing water, the substrate was wiped with isopropyl alcohol to obtain a coating substrate. The above solution was formed into a film on the thus prepared glass substrate by dipping, dried at 120 ° C. for 20 minutes, and cooled to room temperature. The obtained film has a neutral color tone for both reflection and transmission, and has a film thickness measured with a surface roughness meter (DEKTAK 3030 SL).
OAN) (5 μm).

Forming and Drying a Protective Film A liquid was formed by spin coating on the substrate obtained in
Dried for minutes. The spin coating was performed at a rotation speed of 1000 rpm for 30 seconds.

As a result of evaluating the performance of the obtained water-absorbing organic-inorganic composite coating film, as shown in Table 1, good results were obtained in all cases. The film thickness was measured with a surface roughness meter in the same manner as described above, but it was 10 nm or less. Further, when the obtained sample was examined by exhalation, no fogging occurred.

[0046]

[Table 1]

[0047]

Example 2 The drying temperature of the water-absorbing organic-inorganic mixed film was set to 90
C. and the same as in Example 1 except that the drying temperature of the protective film was 70.degree. C., and the film thickness after drying was 10 .mu.m. In addition, when the obtained sample was exhaled, no clouding occurred. The performance evaluation results were all good as shown in Table 1.

[0048]

Example 3 The drying temperature of the water-absorbing organic-inorganic mixed film was set to 150
C. and the same temperature as in Example 1 except that the drying temperature of the protective film was set to 120 ° C., and the film thickness after drying was 3.2 μm.
In addition, when the obtained sample was exhaled, no clouding occurred. The performance evaluation results were all good as shown in Table 1.

[0049]

Example 4 The composition of polyvinyl acetal and silica was 9
Everything was the same as Example 1 except that the content was 5: 5% by weight, and the film thickness after drying was 5.3 μm. In addition, when the obtained sample was exhaled, no clouding occurred. The performance evaluation results were all good as shown in Table 1.

[0050]

Example 5 The same procedure as in Example 1 was carried out except that the raw material of the water-absorbing organic polymer was hydroxypropylcellulose (brand M: manufactured by Nippon Soda), and the film thickness after drying was 3.8 μm. In addition, when the obtained sample was exhaled, no clouding occurred. The performance evaluation results were all good as shown in Table 1.

[0051]

Example 6 The same procedure as in Example 1 was carried out except that the raw material of the water-absorbing organic polymer was hydroxypropylcellulose (brand H: manufactured by Nippon Soda) and the weight percentage with respect to silica was 95: 5. The film thickness was 7.4 μm.
In addition, when the obtained sample was exhaled, no clouding occurred. The performance evaluation results were all good as shown in Table 1.

[0052]

Example 7 The same procedure as in Example 1 was carried out except that the raw material of the water-absorbing organic polymer was polyvinyl alcohol (reagent, polymerization degree: 1400, manufactured by Kishida Chemical Co.), and the film thickness after drying was 4.6.
μm. In addition, when the obtained sample was exhaled, no clouding occurred. The performance evaluation results were all good as shown in Table 1.

[0053]

Example 8 The procedure of Example 1 was repeated except that the raw material of the water-absorbing organic polymer was polyvinyl alcohol (reagent, polymerization degree: 2000, manufactured by Kishida Chemical Co.), and the film thickness after drying was 7.1.
μm. In addition, when the obtained sample was exhaled, no clouding occurred. The performance evaluation results were all good as shown in Table 1.

[0054]

Example 9 Polyvinyl acetal and hydroxypropyl cellulose (reagent, 150 to 400 cp: manufactured by Nippon Soda) were set to a solid content ratio of 1: 1 and the composition of the mixed organic polymer and silica was set to 95: 5% by weight. Were all the same as in Example 1, and the film thickness after drying was 6 μm. In addition, when the obtained sample was exhaled, no clouding occurred. The performance evaluation results were all good as shown in Table 1.

[0055]

Example 10 Polyvinyl acetal and polyvinyl pyrrolidone (reagent, K-15: manufactured by Kishida Chemical Co.) were used at a solid content ratio of 1: 1.
Everything was the same as in Example 1 except that the content was 5: 5% by weight, and the film thickness after drying was 4.7 μm. In addition, when the obtained sample was exhaled, no clouding occurred. The performance evaluation results were all good as shown in Table 1.

[0056]

Comparative Example 1 Polyvinyl acetal was diluted with a mixed solvent of Echinen F-1 and water to obtain a solid content of 4 wt%.
Was formed on a glass substrate by a spin coating method, and dried at 120 ° C. for 20 minutes. The film thickness is 4.8
μm. In addition, although the obtained sample did not produce fogging when exhalation was applied, the performance was evaluated as shown in Table 2, and the film peeled off after a film strength test, a water resistance test, a water wiping test, and an acid resistance test. Was not.

[0057]

[Table 2]

[0058]

Comparative Example 2 The raw materials and solution composition for forming the water-absorbing organic-inorganic mixed film were all the same as in Example 1, and no protective film was formed. The film thickness after drying was 6.6 μm. In addition, when the obtained sample was subjected to exhalation, no fogging occurred, but after the endurance test, all the exhalation caused fogging.

[0059]

Comparative Example 3 The raw material for forming the water-absorbing organic-inorganic mixed film and the composition of the solution were all the same as in Example 1, and the raw material of the protective film was ethyl silicate (reagent: manufactured by Kishida Chemical Co.) )). The thickness of the water-absorbing organic polymer after drying was 6 μm, and the thickness of the protective film was 10 nm or less. In addition, the obtained sample became cloudy when exhaled, and as shown in Table 2, the appearance after the test was good except for the film strength test, but all the exuded clouded.

[0060]

COMPARATIVE EXAMPLE 4 A water-absorbing film was prepared by diluting polyvinyl acetal with a mixed solvent of echinene F-1 and water to a solid concentration of 4% by weight on a glass substrate by spin coating. After drying at 20 ° C. for 20 minutes, the protective film was the same as in Example 1. The thickness of the water absorbing film was 6 μm.
The protective film had a thickness of 10 nm or less. In addition, when the obtained sample was exhaled, no clouding occurred,
As shown in Table 2, the film was peeled except for the evaluation of antifogging property and the cold temperature test.

[0061]

According to the substrate on which the anti-fogging film of the present invention is formed, excellent anti-fogging property can be maintained for a long period of time by a specific means which is stable, reliable and easy without any troublesome steps and easily. It can be obtained inexpensively and efficiently with high productivity, has no defects such as cracks, has excellent transparency, and has no practical problem in abrasion resistance. Furthermore, without damaging the color tone of the base material, it is suitable for industrial use such as architectural window materials or mirrors for bathrooms and washrooms, as well as door mirrors for automobiles, front, rear,
The present invention can provide a useful antifogging coating substrate widely applicable to various coatings such as window materials such as side windows and various glass articles used indoors and outdoors, and a method for producing the same.

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Hideki Yamamoto 1510 Oguchi-cho, Matsusaka-shi, Mie Central Glass F-term in Glass Research Laboratories Co., Ltd. 4G059 AA01 AC21 AC22 FA05 FA07 FA12 FA13 FA28 GA01 GA04 GA16 4H020 AA01 AA03 AB02 BA31 BA34

Claims (9)

[Claims] An antifogging film-forming group, wherein a surface of a substrate is coated with a water-absorbing organic-inorganic composite coating comprising a water-absorbing organic polymer and an inorganic substance, and the surface is water-repellent. Wood. 2. The water-absorbing organic-inorganic composite coating is a water-absorbing organic polymer comprising at least one of hydroxypropylcellulose, polyvinyl alcohol, polyvinyl acetal, polyvinylpyrrolidone and polyvinyl acetate.
The antifogging film-forming substrate according to claim 1, comprising an inorganic substance containing silica and silica. 3. The composition of the water-absorbing organic-inorganic composite coating is such that the content of the organic polymer is 99.5 to 95 wt% and the content of the inorganic substance containing silica is 0.5 to 5.0 wt%. The antifogging film-forming substrate according to claim 1 or 2, wherein: 4. The base material according to claim 1, wherein a water-repellent coating is formed as the water-repellent treatment. 5. The substrate according to claim 4, wherein the water-repellent coating is made of a silicon compound. 6. The silicon compound according to claim 5, wherein at least one of the functional groups of the silicon compound is a methyl group (—CH ₃ ), and the other functional group is an isocyanate group (—NCO). Fogging film forming substrate. 7. The film thickness of the water-absorbing organic-inorganic composite coating is 2-10.
The antifogging film-forming substrate according to claim 1, wherein the thickness of the water-repellent coating is 10 nm or less in a range of μm. 8. A first drying treatment is carried out after applying a solution in which a water-absorbing organic polymer and a silicate compound are uniformly dissolved in a mixed solvent of lower alcohol and water to a substrate surface, followed by a first drying treatment, and a protective film thereon. A second drying treatment after the application of the water-repellent coating, which is a method for producing an antifogging coating-forming substrate. 9. The first drying treatment is performed at 90 to 150 ° C. and / or the second drying treatment is performed at 70 to 120 ° C.
The method for producing a substrate having an antifogging film according to claim 8, wherein the method is carried out at a temperature of ℃.