JP2000319512A - Ordinary temperature-curable composition, coating liquid which use the same and is used for forming ultraviolet light-screening film and ultraviolet light-screening film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject composition giving coating liquids which can be cured at ordinary temperature to form UV light-screening films having high surface strengths, by mixing and reacting two kinds of specific alkoxysilanes. SOLUTION: This ordinary temperature-curable composition comprises a substance of the formula [X1, X2 are each an alkoxy which can be hydrolyzed to produce a silanol, such as methoxy, ethoxy, propoxy or butoxy; Y1, Y2 are each an alkyl such as methyl, ethyl, propyl or butyl; (a), (b), (c) and (d) are such numbers as satisfying the following inequalities and equations: 1<=(a)<=3, (a)+(b)=3, 1<=(c)<=3, and (c)+(d)=3] which is prepared by mixing and reacting a glycidoxypropyl group-containing alkoxysilane with an aminopropyl group-containing alkoxysilane preferably in a molar ratio of 2:1 to 1:1. The composition is compounded with a dilution solvent, a curing catalyst, and a UV light absorbent to provide a coating liquid for forming UV light- screening films which can be cured at ordinary temperature.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultraviolet shielding material applicable to glass, plastic, and other substrates requiring an ultraviolet shielding function. More specifically, the present invention relates to a specific room temperature curable composition. The present invention relates to a coating solution for forming an ultraviolet shielding film containing a component and an ultraviolet shielding film having a high surface hardness formed using the coating solution.

[0002]

2. Description of the Related Art Ultraviolet rays in a short wavelength region of 400 nm or less in artificial rays such as sunlight, fluorescent lamps and cathode ray tubes have an adverse effect on the human body such as sunburn, spots, carcinogenesis and visual impairment.
It also causes deterioration of the mechanical strength of the article, deterioration of appearance such as fading, deterioration of food, deterioration of color tone of printed matter, and the like. Also,
Insects can travel at specific wavelengths in the visible or ultraviolet region. In particular, many insects are strongly attracted to ultraviolet rays, and this causes various problems in artificial lighting such as a fluorescent lamp having a spectral wavelength in the ultraviolet region. For example, it is required to suppress the transmission of ultraviolet rays from windows to cause fading of internal fabrics or the like due to sunlight rays from windows of buildings or automobiles and to cause sunburn on human bodies. In addition, fluorescent lamps are widely used as lighting equipment, but in the display and sale of products, the ultraviolet light of the installed fluorescent lamps causes the articles to fade and the food to be deteriorated. Insects fly when they sense the ultraviolet light emitted by the fluorescent light, and mix into articles and foods.
In addition, many insects fly to streetlights, show windows, and windows, causing discomfort. In order to shield these harmful ultraviolet rays, a glass, a plastic, a film, and a coating solution containing the ultraviolet absorber, which has an ultraviolet ray absorbing function by kneading an ultraviolet ray absorbing agent, are used to apply an ultraviolet ray shielding film on the substrate. Glass, plastic, film, and the like, which are formed to have an ultraviolet shielding function, are used. In order to provide an ultraviolet shielding function to a substrate already used, such as a window of a building or a window of a vehicle, a method of forming an ultraviolet shielding film using a coating solution containing an ultraviolet absorbent is required. Simple and good. However, such a method requires that the coating liquid can be cured at room temperature. If the coating liquid can be cured at room temperature, there is no need to use a special curing device even in a factory, which is advantageous in terms of cost. In applications such as hotel windows and automobile windows, the surface is easily damaged due to cleaning and opening and closing, and the surface hardness of the cured film is required. Some coating liquids using organic binders can be cured at room temperature, but the film strength after coating and curing is weak and not practical. Further, with an inorganic binder such as silicate, the film strength after curing is practical, but heating is required for curing, and it does not cure at room temperature. As described above, there is no coating liquid for forming an ultraviolet shielding film which can be cured at room temperature and whose cured film gives sufficient surface strength.

[0003]

DISCLOSURE OF THE INVENTION The present invention has been made as a result of intensive studies to solve the above-mentioned problems of the prior art, and as a result, a novel cold-setting composition has been synthesized, and a coating solution for forming an ultraviolet shielding film containing the same has been developed. The inventors have invented an ultraviolet shielding film using the coating liquid and a substrate having the ultraviolet shielding film. That is, the present invention provides a novel cold-setting composition, and
It is an object of the present invention to provide an ultraviolet shielding film having a high surface hardness and a substrate having the film by using a coating liquid for forming an ultraviolet shielding film containing the composition.

[0004]

The gist of the invention described in claim 1 is that a glycidoxypropyl group-containing alkoxysilane and an aminopropyl group-containing alkoxysilane are mixed and reacted, and represented by the general formula (I). It is a room temperature curable composition containing the substance to be cured.

[0005]

Embedded image (Wherein, X1 and X2 each represent an alkoxyl group that produces silanol by hydrolysis such as a methoxy group, an ethoxy group, a propoxy group, and a butoxy group; Y1 and Y2 represent a methyl group;
Represents an alkyl group such as an ethyl group, a propyl group, and a butyl group;
3, 1 ≦ c ≦ 3, a number that satisfies the relationship of c + d = 3. )

The mixing ratio of the glycidoxypropyl group-containing alkoxysilane to the aminopropyl group-containing alkoxysilane is preferably in a molar ratio of 2: 1 to 1: 1.
The invention according to claim 3 is a coating liquid for forming an ultraviolet shielding film that can be cured at room temperature, which contains a room temperature curable composition, a diluting solvent, a curing catalyst, and an ultraviolet absorber. At least one kind is the room temperature curable composition of the above general formula (I). The contained ultraviolet absorber is one or both of a benzophenone-based and a benzotriazole-based organic ultraviolet absorber, and the content is 0.5 to 7 wt.
%, And the curing catalyst is preferably boron trifluoride piperidine. The invention according to claim 6 is an ultraviolet shielding film obtained by applying and curing the coating liquid for forming an ultraviolet shielding film on a substrate, and has a high surface strength. Claim 7
The invention described in (1) is a substrate having an ultraviolet shielding ability on which the ultraviolet shielding film is formed. That is, the composition according to claim 1 of the present application is a room-temperature curable composition characterized by reacting and binding a glycidoxypropyl group and an aminopropyl group, and containing the composition for forming an ultraviolet shielding film. The coating liquid cures at room temperature, and an ultraviolet shielding film having a high surface hardness can be obtained.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. The cold-setting composition according to the first aspect of the present invention is obtained by reacting an alkoxysilane having a glycidoxypropyl group with an alkoxysilane having an aminopropyl group. Examples of the glycidoxypropyl group-containing alkoxysilane include glycidoxypropyltrimethoxysilane, glycidoxypropylmethyldimethoxysilane, glycidoxypropyltriethoxysilane, and glycidoxypropylmethyldiethoxysilane. Examples of the alkoxysilane having an aminopropyl group include aminopropyltriethoxysilane and aminopropyltrimethoxysilane.

Although the reaction ratio of these compounds is not particularly limited, the mixing ratio between the glycidoxypropyl group-containing alkoxysilane and the aminopropyl group-containing alkoxysilane is usually in the range of 2: 1 to 1: 1. Preferably, there is. When the ratio of the glycidoxypropyl group-containing alkoxysilane is more than 2: 1, the curing of the coating solution for an ultraviolet shielding film is slow, and the surface hardness of the formed ultraviolet shielding film is low. Further, when the ratio of the aminopropyl group-containing alkoxysilane is more than 1: 1, the coating solution for the ultraviolet shielding film cures too quickly, and the formed ultraviolet shielding film is whitened. The reaction conditions are room temperature (25 ° C.) to 80
The mixture is agitated for one hour at ℃ and aged at room temperature for 14 days to obtain a desired room temperature curable composition. The aging time can be further reduced by selecting the temperature during mixing and stirring. The basic structure of the obtained reactant is represented by the above general formula (I). That is, it has an alkoxyl group at both ends of the molecule. This terminal alkoxyl group is hydrolyzed at room temperature to produce highly reactive silanol, which can be polymerized by itself or combined with other components by condensation polymerization. Further, since the terminal alkoxyl group is hydrolyzed and may exist in the form of an oligomer obtained by condensation polymerization of silanol, the reaction product is a mixture and has room temperature curability. In claims 1 and 2 of the present application, this is expressed as "a cold-setting composition containing a substance represented by the general formula (I)". In addition, the "room temperature curable composition" in claim 3 means that the composition is cured at room temperature without particularly requiring heating, and at least one of them is described in claim 1 or 2. Is a room temperature curable composition.

The coating solution for an ultraviolet shielding film in the invention of claim 3 of the present application contains at least one cold-setting composition of the invention of claim 1 or 2 as a cold-setting composition. The curing is caused by hydrolysis of the alkoxyl group in the cold-curable composition molecule and subsequent polymerization by silanol condensation polymerization. The siloxane bond thus formed is strong, and can form a robust coating film.

The diluting solvent in the coating solution for forming the ultraviolet shielding film is not particularly limited, and can be selected according to the coating conditions, the coating environment, and the type of solids in the coating solution. Various solvents such as alcohols such as isobutyl alcohol, ether alcohols such as ethylene glycol monomethyl ether and ethylene glycol monoethyl ether, esters such as methyl acetate and ethyl acetate, and ketones such as methyl ethyl ketone and cyclohexanone can be used. One or more solvents may be used in combination depending on the application.

In order to provide the formed ultraviolet shielding film with ultraviolet shielding ability, the coating liquid for forming an ultraviolet shielding film contains one or both of a benzophenone-based and a benzotriazole-based organic ultraviolet absorber. Content is 0.5-7
wt% is preferred. 0.5wt of UV absorber
% Or less, the ultraviolet shielding ability of the formed ultraviolet shielding film is not sufficient, and if it exceeds 7 wt%, the ultraviolet absorbent exudes to the surface of the film or fogging occurs. Further, this room temperature curable composition has moisture curability, but in order to make the curing speed at room temperature practical, it is necessary to add a curing catalyst to the coating solution for forming an ultraviolet shielding film. As the curing catalyst, boron trifluoride or the like is used, and boron trifluoride piperidine is preferred because it is easy to handle. The curing time can be controlled by changing the amount of catalyst added, and the range of application is expanded.

The coating solution for forming an ultraviolet shielding film of the present invention is applied to a substrate such as a glass, a plastic plate or a film and cured at room temperature to form an ultraviolet shielding film having an ultraviolet shielding ability having a high surface hardness on the substrate. Can be formed.
The method of applying the coating liquid for forming the ultraviolet shielding film is not particularly limited, and the processing liquid is flat and thin and uniform, such as a spin coating method, a spray coating method, a dip coating method, a screen printing method, a method using a cloth or a brush. Any method may be used as long as it can be applied to the surface. The ultraviolet shielding film formed on the substrate gives the substrate a high surface hardness and an ultraviolet shielding function, and suppresses deterioration of the substrate itself due to ultraviolet rays. The substrate on which the ultraviolet shielding film is formed as described above has high surface hardness and ultraviolet shielding ability.

[0013]

Examples and Comparative Examples Hereinafter, the present invention will be described in more detail with reference to Examples. Example 1 600 g of glycidoxypropyltrimethoxysilane and 400 g of aminopropyltriethoxysilane were mixed, stirred for 1 hour with a magnetic stirrer, and aged at room temperature for 14 days to obtain 1000 g of a desired room temperature curable composition (synthesis). Liquid 1). 25 g of Synthetic Solution 1 and 5 g of a benzotriazole-based ultraviolet absorber, 35 g of isobutyl alcohol, and 25 g of propylene glycol monoethyl ether were mixed and stirred.
g and stirred to prepare a coating solution for forming an ultraviolet shielding film. Apply 3 m of this coating solution for forming an ultraviolet shielding film.
m on a soda lime glass substrate and cured at room temperature to obtain an ultraviolet shielding film. The transmittance of the obtained ultraviolet shielding film was measured using a spectrophotometer manufactured by Hitachi, Ltd.
The ultraviolet transmittance (τuv) was calculated according to O9050. In addition, a wear test was performed using a wear wheel CS10f with a load of 250 g and 50 rotations using a Taber abrasion tester, and the surface hardness of the film was evaluated by the change in haze before and after the test (ΔH).
The UV transmittance was 0.28%, and it was confirmed that the UV shielding ability was sufficient. ΔH is 4.8%, and a film having a high surface hardness is formed.

Comparative Example 1 For comparison, the transmittance of a 3 mm soda lime glass substrate itself was measured using a spectrophotometer manufactured by Hitachi, Ltd.
The ultraviolet transmittance (τuv) was calculated according to SO9050. The ultraviolet transmittance (τuv) is 70.72%.

Example 2 68.1 g of glycidoxypropyltrimethoxysilane and 31.9 g of aminopropyltriethoxysilane were mixed, stirred for 1 hour with a magnetic stirrer, aged for 14 days at room temperature, and cured at room temperature for 100 g. Was obtained (synthesis liquid 2). The mixture molar ratio of glycidoxypropyltrimethoxysilane and aminopropyltriethoxysilane is 2: 1. A coating solution for forming an ultraviolet shielding film was prepared in the same manner as in Example 1 except that Synthetic Solution 1 of Example 1 was changed to Synthetic Solution 2, and an ultraviolet shielding film was formed and evaluated. The ultraviolet transmittance (τuv) is 0.66% and the ultraviolet shielding ability is sufficient,
ΔH is 11.2%, and there is no practical problem in surface hardness.

Example 3 51.6 g of glycidoxypropyltrimethoxysilane and 48.4 g of aminopropyltriethoxysilane were mixed, stirred for 1 hour with a magnetic stirrer, aged for 14 days at room temperature, and cured at room temperature for 100 g. Was obtained (Synthesis liquid 3). The mixture molar ratio of glycidoxypropyltrimethoxysilane and aminopropyltriethoxysilane is 1: 1. A coating solution for forming an ultraviolet shielding film was prepared in the same manner as in Example 1 except that Synthetic Solution 1 of Example 1 was changed to Synthetic Solution 3, and an ultraviolet shielding film was formed and evaluated. The ultraviolet transmittance (τuv) is 0.51% and the ultraviolet shielding ability is sufficient.
ΔH was 3.5% and the surface hardness was high.

Comparative Example 2 72.7 g of glycidoxypropyltrimethoxysilane and 27.3 g of aminopropyltriethoxysilane were mixed, stirred for 1 hour with a magnetic stirrer, aged for 14 days at room temperature, and cured at room temperature for 100 g. Was obtained (Synthetic solution 4). The mixing molar ratio of glycidoxypropyltrimethoxysilane and aminopropyltriethoxysilane is 2.5: 1. A coating solution for forming an ultraviolet shielding film was prepared in the same manner as in Example 1 except that Synthetic Solution 1 of Example 1 was changed to Synthetic Solution 4, and an ultraviolet shielding film was formed and evaluated. The ultraviolet transmittance (τuv) is 0.80% and the ultraviolet shielding ability is sufficient, but ΔH is 30.2% and the surface hardness is low.

Comparative Example 3 41.6 g of glycidoxypropyltrimethoxysilane and 58.4 g of aminopropyltriethoxysilane were mixed, stirred for 1 hour with a magnetic stirrer, aged at room temperature for 14 days, and cured at room temperature for 100 g. Was obtained (Synthesis liquid 5). The mixture molar ratio of glycidoxypropyltrimethoxysilane and aminopropyltriethoxysilane is 1: 1.5. A coating solution for forming an ultraviolet shielding film was prepared and an ultraviolet shielding film was formed in the same manner as in Example 1 except that Synthetic Solution 1 of Example 1 was changed to Synthetic Solution 5. The coating liquid for forming the ultraviolet shielding film had a high curing speed, and the coating film was whitened.

Comparative Example 4 The procedure of Example 1 was repeated, except that the amount of the benzotriazole-based UV absorber was 7.5 g and the amount of propylene glycol monoethyl ether was 22.5 g. A coating solution was prepared, an ultraviolet shielding film was formed, and evaluated. Although τuv was 0.03%, the ultraviolet shielding ability was sufficient, but when the coated film was allowed to stand at room temperature for 7 days, seepage of the ultraviolet absorber was observed on the surface of the film.

Example 4 600 g of glycidoxypropyltriethoxysilane and 400 g of aminopropyltrimethoxysilane were mixed, stirred for 1 hour with a magnetic stirrer, and aged for 14 days at room temperature to obtain 1000 g of a desired room temperature curable composition. (Synthetic solution 6). 25 g of synthetic solution 6 and 5 g of a benzophenone-based ultraviolet absorber, 35 g of isobutyl alcohol,
5 g of propylene glycol monoethyl ether was mixed and stirred, and 10 g of a solution of boron trifluoride piperidine in isobutyl alcohol (concentration: 10 wt%) was further added and stirred to prepare a coating solution for forming an ultraviolet shielding film. Forming an ultraviolet shielding film in the same manner as in Example 1,
evaluated. The ultraviolet light application rate (τuv) was 1.21%, and the ultraviolet light shielding ability was sufficient, and ΔH was 4.5%, and the surface hardness was high.

Comparative Example 5 5 g of a benzophenone-based ultraviolet absorber, 16.7 g of a lacquer-type room-temperature-curable urethane resin (solvent: isopropyl alcohol, solid content: 30%) as a resin binder,
As a diluting solvent, 53.3 g of isobutyl alcohol and 25 g of propylene glycol monoethyl ether were mixed and stirred to prepare a coating liquid for an ultraviolet shielding film. An ultraviolet shielding film was formed and evaluated in the same manner as in Example 1. τuv is 0.0
3%, which is sufficient for ultraviolet shielding ability, but ΔH is 30.
0% and the surface hardness is low.

[0022]

As shown in the above examples, the use of the novel room temperature curable composition provides a coating solution for an ultraviolet shielding film which can be cured at room temperature to form an ultraviolet shielding film having high surface strength. Was. Further, according to the present invention, it has become possible to impart a high surface strength and an ultraviolet shielding function to a substrate.

Claims (7)

[Claims] 1. A room-temperature-curable composition comprising a substance represented by the general formula (I) obtained by mixing and reacting a glycidoxypropyl group-containing alkoxysilane and an aminopropyl group-containing alkoxysilane. . Embedded image (Wherein, X1 and X2 each represent an alkoxyl group that produces silanol by hydrolysis such as a methoxy group, an ethoxy group, a propoxy group, and a butoxy group; Y1 and Y2 represent a methyl group;
Represents an alkyl group such as an ethyl group, a propyl group, and a butyl group;
3, 1 ≦ c ≦ 3, a number that satisfies the relationship of c + d = 3. ) 2. The room-temperature curability according to claim 1, wherein the mixing ratio of the glycidoxypropyl group-containing alkoxysilane and the aminopropyl group-containing alkoxysilane is in a molar ratio of 2: 1 to 1: 1. Composition. 3. A coating liquid for forming an ultraviolet shielding film which can be cured at room temperature, comprising a room temperature curable composition, a diluting solvent, a curing catalyst, and an ultraviolet absorber, wherein at least one kind of the room temperature curable composition is used. A coating liquid for forming an ultraviolet shielding film, wherein the coating liquid is the room temperature curable composition according to claim 1. 4. The curing at room temperature according to claim 3, wherein one or both of benzophenone-based and benzotriazole-based organic ultraviolet absorbers are contained as the ultraviolet absorber in an amount of 0.5 to 7 wt%. Possible coating solution for forming ultraviolet shielding film. 5. The coating solution for forming an ultraviolet shielding film curable at room temperature according to claim 3, wherein the curing catalyst is boron trifluoride piperidine. 6. The method according to claim 3, wherein
An ultraviolet-ray shielding film obtained by applying and curing the coating solution for forming an ultraviolet-ray shielding film described in 1 above to a substrate. 7. A substrate having an ultraviolet shielding function on which the ultraviolet shielding film according to claim 6 is formed.