JPS6056194B2 - Resin composition for coating - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a transparent coating composition that has excellent antifogging properties and also has excellent water resistance and abrasion resistance.

One of the biggest problems with indoor mirrors such as bathroom mirrors and vanity mirrors is that when the temperature of the glass surface falls below the dew point of the environment, fogging and condensation occur on the surface. For this reason, it is often unable to function as a mirror, causing inconvenience. In addition, similar to mirrors, window glasses, eyeglass lenses, instrument panels, etc. have many similar inconveniences. Therefore, imparting antifogging properties to the surface of materials such as glass has high practical value, and there is a strong demand for this from various fields.

Many attempts have been made in various fields regarding this anti-fogging method, but at present no fully satisfactory method has yet been found. One such method is to form an antifogging film on the surface of a substrate such as glass by coating, and some methods are commercially available. However, at present, there are problems with antifogging properties, water resistance, and abrasion resistance in high temperature and high humidity environments such as bathrooms. In view of the above, the present inventors have developed a coating film that has excellent antifogging properties even under harsh environments such as high temperature and high humidity, and has water resistance and abrasion resistance. The present invention was accomplished with the aim of developing a composition that can be formed on the surface of a substrate such as glass without the need for a chemical agent.

That is, the present invention provides a partial hydrolyzate or hydrolyzate of an alkoxysilane selected from the following group [I], a polymerizable monomer selected from the group [■], and a polymerizable monomer selected from the group [■]. A coating resin composition consisting of a copolymer with an alkyl alkoxysilane having a polymerizable unsaturated group, a curing catalyst, and a surfactant, and can be applied to the surface of a material such as glass and post-cured by heating. This forms an anti-fog coating film.

Group [I]: Alkoxysilanes whose general formula is R3α-Si-()R1 or R30Si-ORI or OR2OR”R30-Si-ORI, in which R1,
R3, R3, R4, R' and R° are straight chain or branched alkyl groups having 4 or less carbon atoms.

[■] Group: -The general formula is 1! Or CH2-ACX-C-O-R7 CH2=℃X-℃-σR8-O-)-nR? It is a polymerizable monomer represented by the formula, where X is H or HCH3, and R7 is a hydroxyalkyl group,
1CH, CH, OH or 1, and R' is 1℃H
CH2--CH2CH2- or 1, R9 is H or CH3, and n is an integer from 2 to 20.

[■] Group; general formula is CH2-4SX-Si-ORI or CH2■℃X-℃-O-R13-Si-ORI1ORI
.

A polymerizable monomer represented by the formula, where X is H or C
H, R″O, RH and R″″ are alkyl groups having 2 or less carbon atoms, and R″′ is a straight chain or branched alkyl group having 5 or less carbon atoms.

Partial hydrolysates of alkoxysilanes (group I) or cured products of hydrolysates form three-dimensional Si-O-Si bonds similar to the molecular structure of glass, and when used alone, they are extremely hard. However, anti-11R30-Sll
-0R1 or R3σ-SIi--0R1 or an alkoxysilane represented by -Rl, R3 in the formula
, R3, R4, R5 and R6 are straight chain or branched alkyl groups having 4 or less carbon atoms.

[■] Group: Polymerizable monomers whose general formula is Rw-CY--n-P7 and up to C, where X is H or H
CH3, R7 is a hydroxyalkyl group and is one CH2
CH2OH or I[[-“2-” and R3 is 1C
H2CH2- or “one”2, R9 is HC
H7 or CH3, and n is an integer of 2 to 20.

[■] Group: Polymerizable monomers whose general formula is CH2-4SX-SIi (Rll or
H3, RlO, Rll and Rl2 are alkyl groups having 2 or less carbon atoms, and Rl3 is a straight chain or branched alkyl group having 5 or less carbon atoms.

Partial hydrolysates of alkoxysilanes ([1] group) or cured products of hydrolysates form three-dimensional Si-0-Si bonds similar to the molecular structure of glass, and when used alone, they are extremely hard. However, it has the disadvantage of being brittle and prone to cracking.

It has been found that by adding this to a coating resin composition, the hardness of the coating film can be improved and the antifogging properties can be maintained. In addition, the copolymers of the above [■] group and [■] group mainly have a water absorption and antifogging effect due to the hydrophilicity of the [■] group, and also have a water absorption and antifogging effect due to the copolymerization with the alkyl alkoxysilane of the [■] group. It is possible to increase the hardness due to the three-dimensional reactive group (alkoxy group) of the alkylalkoxysilane and the adhesion to the glass substrate.

Hydrophilic polymers produced by polymerization in the [■] group have a large water absorption capacity due to their hydrophilicity, and this performance is thought to contribute to the antifogging property.

Although this polymer is hydrophilic, its surface chemistry is similar to that of general plastics, so it maintains its antifogging properties until water absorption into the polymer reaches saturation. sex decreases. Therefore, adding a surfactant increases the water absorption rate and also works to reduce the contact angle for excess water even above the water absorption saturation point of the resin, resulting in improved antifogging properties. maintained.
The curing catalyst accelerates the curing of the resin at low temperatures and in a short period of time.
It also has the effect of improving the adhesion and abrasion resistance between the resin and the base material.

The resin composition of the present invention is produced by the following method.

That is, first, an alkoxysilane selected from group [1] is partially hydrolyzed or hydrolyzed.

Next, a hydrophilic monomer selected from the [previous group] and an alkyl alkoxysilane selected from the [■] group are copolymerized, a hydrolyzate of the alkoxysilane is added to the obtained copolymer, and further A coating resin composition is prepared by adding appropriate amounts of a curing catalyst and a surfactant.

Representative examples of the alkoxysilanes of group [1], hydrophilic monomers of group [■], and alkyl alkoxysilanes of group [■] used in the present invention are as follows. be.

That is, specific examples of group [1] are tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetrabutoxysilane, methyltrimethoxysilane, methyltriethoxysilane, methyltripropoxysilane, methyltributoxysilane, ethyltrimethoxysilane, ethyl Triethoxysilane, engineered tripropoxysilane, ethyltriptopoxysilane, ethyltriptoxysilane, propyltrimethoxysilane, propyltriethoxysilane, propyltripropoxysilane, propyltriptoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, Dimethylpropoxysilane, dimethyldibutoxysilane, diethyldimethoxysilane, diethyldiethoxysilane,
Diethyldiethoxysilane, diethyldibutoxysilane, methylethyldimethoxysilane, methylpropyldiethoxysilane, etc.

[■] Specific examples of group 2-Hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, diethylene glycol monoacrylate, diethylene glycol monomethacrylate, methoxydiethylene glycol monoacrylate, methoxydiethylene glycol monomethacrylate, Ethylene glycol monoacrylate, triethine glycol monomethacrylate, methoxytriethylene glycol monoacrylate, methoxytriethylene glycol monomethacrylate, polyethylene glycol monoacrylate, polyethylene glycol monomethacrylate, etc.

Specific examples of the [■] group: vinyltrimethoxysilane, vinyltriethoxysilane, vinyltripropoxysilane, vinyltributoxysilane, γ-methacryloxyethyltrimethoxysilane,
γ-methacryloxyethyltriethoxysilane, γ-acryloxyethyltrimethoxysilane, γ-acryloxyethyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropyltriethoxysilane, γ-acryloxypropyl Trimethoxysilane, γ-acryloxypropylmethoxysilane, etc.

However, these are just examples and are not limited to these.

The partial hydrolysis or hydrolysis reaction of the alkoxysilane selected from the above group [1] can be carried out by uniformly mixing the alkoxysilane selected from the group [1] in a water-soluble solvent, and performing partial hydrolysis or hydrolysis. The reaction is proceeded by adding an amount of water corresponding to , and adding an appropriate amount of a hydrolysis catalyst.

The water-soluble solvents used in this case include all other water-soluble solvents such as methanol, ethanol, propanol, isopropanol, acetone, methyl ethyl ketone, dioxane, ethyl acetate, methyl acetate, methyl cellosolve, ethyl cellosolve, methyl cellosolve acetate, etc. Hydrolysis catalysts include sulfuric acid, hydrochloric acid, sodium hydroxide,
Contains potassium hydroxide, P-toluenesulfonic acid, etc.

Radical polymerization catalysts used for the copolymerization of hydrophilic monomers of the [older group] and alkyl alkoxysilanes of the [■] group include peroxides, hydroperoxides, redox catalysts, azobis catalysts, etc. Contains all radical polymerization catalysts that can cause Furthermore, the curing catalyst used in the present invention is a combination of a partial hydrolyzate or a hydrolyzate of alkoxysilanes from the [1] group, hydrophilic monomers from the [older group], and alkyl alkoxysilanes from the [■] group. Catalysts necessary for the condensation reaction that occurs when the copolymer mixture is applied to a substrate and the film is cured by heating, specifically, sulfuric acid, P-toluenesulfonic acid, sodium acetate, potassium acetate, Triethanolamine titanate, tin octenoate, lead octenoate, octenoic acid. Examples include zinc and dibutyltin octoate.

Furthermore, the surfactant used in the present invention synergistically increases the antifogging property of the hydrophilic polymer, and nonionic and anionic surfactants are effective as surfactants, with nonionic surfactants being particularly effective. ．． Excellent type surfactant. Specifically, polyethylene glycol alkyl ether, polyethylene glycol nonylphenyl ether,
These include polyethylene glycol alkyl allyl ether, polypropylene glycol polyethylene glycol ether, polyethylene glycol alkyl amine, and polyethylene glycol fatty acid ester.

Next, to explain the respective mixing ratios, the monomer ratio in the copolymerization of the hydrophilic monomers of the [■] group and the alkylalkoxysilanes of the [■] group is as follows:
(2) The proportion of the hydrophilic monomer is 60 to 99.5 mol%, preferably 85 to 99 mol% of the total amount of alkyl alkoxysilanes in group [1], and partial hydrolysis of alkoxysilanes in group [1] The amount of compound or hydrolyzate added is [■]
5 for the copolymer (hereinafter abbreviated as copolymer) of the hydrophilic monomer of the group and the alkylalkoxysilane of the group [■]
-5% by volume, preferably 10-3% by volume.

In addition, the amount of curing catalyst added is 0.1 to 2
．． % by weight, preferably 0.5-1.0% by weight, and the amount of surfactant added is 0.1-1% by weight, preferably 0.5-5% by weight, based on the copolymer. Heel volume %.

The resin composition thus produced is applied onto the surface of a substrate such as glass to form a film, and then heated and cured at a temperature of 80 to 200°C before use.

Hereinafter, the present invention will be specifically explained with reference to Examples. Example 1 5 parts of methyl ethoxysilane (hereinafter "parts by weight" is abbreviated as "parts") was dissolved in 5 parts of acetone, 6 parts of distilled water was added, and P-
Bring the pH to 3 with toluenesulfonic acid.

This mixture was stirred at room temperature for 2CB1 hours to obtain a partial hydrolyzate of methyltriethoxysilane.

Next, 100 parts of 2-hydroxyethyl methacrylate, 15 parts of vinyltrimethoxysilane and 18 parts of isopropanol were mixed, and 1.0 parts of benzoyl peroxide (BPO) was added. The solution was added and polymerized for 120 minutes at a temperature of 60°C to obtain a colorless and transparent viscous liquid. 10 PHR of a partial hydrolyzate of methyl ethoxysilane was added to this copolymer, and further,
Sodium acetate 1.0 PHR as curing catalyst 1 3P polyethylene glycol alkyl ether as surfactant
Add HR and stir well to prepare a homogeneous composition.
This composition was applied to the surface of a glass substrate by a dipping method, heated and cured at a temperature of 100°C for 4 hours, and a thickness of 12
A colorless and transparent film of μ was formed. This film had a pencil hardness of 4H and did not fog when blown with exhaled air, nor did it fog when exposed to saturated water vapor at 40°C in a 20'C atmosphere. In addition, the cross-section test was 1001100, indicating good adhesion, and in the water resistance test of immersion in warm water at 60°C, there was no change in appearance even after immersion for 2 hours, and no deterioration in antifogging properties or adhesion was observed. .

Example 2 Tetraethoxysilane (4) parts were dissolved in ethanol (4) parts, 10 parts of distilled water was added, and the pH was adjusted to 2 to 3 with sulfuric acid.
Make it.

This mixture is stirred at room temperature for 20 hours to produce a partial hydrolyzate of tetraxysilane. Next, 100 parts of 2-hydroxyethyl acrylate, w parts of γ-methacryloxypropyltrimethoxysilane, and 1 part of ethyl cellosolve
66 parts of benzoyl peroxide (BP
O) 1.0 part was added and 6 powders were polymerized at a temperature of 70°C.

Furthermore, 80% of ethyl cellosolve is added, and the 6-powder reaction is proceeded at a temperature of 85°C to complete the copolymerization. What was obtained is
The polymerization rate was approximately 100%, and the solution viscosity was a colorless, transparent viscous liquid with a viscosity of 1300 CPS. Add 15 PHR of partial hydrolyzate of tetraethoxysilane to this copolymer and mix uniformly, further add 5 PHR of polyethylene glycol nonylphenyl ether as a surfactant and 1 PHR of potassium acetate as a curing catalyst and mix uniformly, A resin composition for coating was prepared.

Apply this material to the surface of the glass base material using the dipping method,
Baking was performed at a temperature of 120°C for 2 hours. After baking, the antifogging coating film was colorless and transparent, the film layer had a thickness of 15μ, and the pencil hardness was ■.

Even if you blow your breath on this material, it will not become cloudy, and
Exposure over saturated water vapor at 40'C in a 20°C atmosphere did not result in haze. Goban eye test is 10011
00, the adhesion was also good.

Further, in a water resistance test by immersion in warm water at 60° C., there was no change in appearance even after 2 hours, and the antifogging properties and adhesion were also good. In addition, when the above composition was formulated without adding a surfactant, it did not become foggy even when exhaled air was blown onto it, but at 20°C
When exposed to saturated water vapor at 40° C. in an atmosphere, it began to become cloudy in seconds and became completely cloudy at 908.

Example 3 Parts of tetraethoxysilane (4) were dissolved in parts of methyl cellosolve (a), w parts of distilled water were added, and partial hydrolysis was carried out in the same manner as in Example 2.

1 (1) part of 2-hydroxyethyl methacrylate, γ-
Copolymerization was carried out in the same manner as in Example 2 using a composition of 1 part of methacryloxypropyltrimethoxysilane and 1 (9) parts of methyl cellosolve.

The obtained resin was a colorless and transparent viscous liquid with a polymerization rate of 100% and a viscosity of 900 CpS.

To this resin solution, 0, 10, 20, 30, 40 PHR of partial hydrolyzate of tetraethoxysilane were added, and 0.5 PHR of P-toluenesulfonic acid was added as a curing catalyst and polyethylene glycol nonylphenyl ether was added as a surfactant. A resin composition for coating was prepared by adding the following ingredients and mixing them uniformly.

Each was applied to the surface of a glass substrate, baked at 120°C for 2 hours, and the antifogging properties, l hardness, etc. were examined depending on the amount of partial hydrolyzate of tetraethoxysilane, and the results shown in Table 1 were obtained. . Example 4 5 parts of tetramethoxysilane, 5 parts of methanol, 6 parts of distilled water
The mixture was partially mixed, and the partial hydrolysis reaction was carried out in the same manner as in Example 2.

Copolymerization was carried out in the same manner as in Example 2 by changing the blending ratio of 2-hydroxyethyl acrylate and γ-methacryloxyethyltrimethoxysilane and using methyl cellosolve as a solvent.

To this copolymer, 10 PHR of partial hydrolyzate of tetramethoxysilane was used as a curing catalyst, and 0.8 PHR of potassium acetate was used as a curing catalyst.
A coating resin composition was prepared by adding 5 PHR of polyethylene glycol nonylphenyl ether as a surfactant.

Claims (1)

[Claims] 1. A partial hydrolyzate or hydrolyzate of an alkoxysilane selected from the following group [I], a polymerizable monomer selected from the group [II], and a polymerizable monomer selected from the group [III]. A coating resin composition comprising a copolymer with an alkyl alkoxysilane, a curing catalyst, and a surfactant. [I] Group: Alkoxysilanes whose general formula is ▲There are mathematical formulas, chemical formulas, tables, etc.▼ or ▲There are mathematical formulas, chemical formulas, tables, etc.▼ or ▲There are mathematical formulas, chemical formulas, tables, etc.▼, and in the formula R^1, R
^2, R^3, R^4, R^5 and R^6 have 4 carbon atoms
The following straight chain or branched alkyl groups. [II] Group: Polymerizable monomers whose general formula is ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ or ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ In the formula, X is H or C
H_3, R^7 is a hydroxyalkyl group -CH
_2CH_2OH or ▲There are mathematical formulas, chemical formulas, tables, etc.▼, and R^3 is -CH_2CH_2- or ▲There are mathematical formulas, chemical formulas, tables, etc.▼, R^9 is H or CH_3, and n is 2~ It is an integer of 20. [III] Group: Polymerizable monomers whose general formula is ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ or ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ In the formula, X is H or C
H_3, R^1^0, R^1^1 and R^1^
2 is an alkyl group having 2 or less carbon atoms, and R^1^3 is a linear or branched alkyl group having 5 or less carbon atoms.