JPH09249830A - One-pack type ultraviolet light-shielding coating material composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject composition capable of effectively shielding ultraviolet light of short wavelengths without quite affecting the transmission of visible light and good in adhesivity to various kinds of substrates by employing both an organic binder and a fluororesin capable of being dissolved in organic solvents. SOLUTION: This coating composition comprises (A) 100 pts.wt. of an organic binder, (B) an ultraviolet light absorbent having effective absorption wavelengths of 270-380nm, (C) 1-20 pts.wt. of an ultrafine particulate white metal oxide, especially ultrafine particulate titanium dioxide, (D) 30-150 pts.wt. of a fluororesin capable of being dissolved in organic solvents, and (E) 0.5-10 pts.wt. of an acidic substance such as phosphoric acid. The component B is preferably 2-(2'-hydroxy-5'-methylphenyl) benzotriazole, etc.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention can be applied uniformly to a wide range of substrates without using a primer.
TECHNICAL FIELD The present invention relates to a one-component ultraviolet ray shielding coating agent composition which effectively shields ultraviolet rays of nm or less. The coating agent according to the present invention can be applied to wood, plastic, metal, glass, paper and the like.

[0002]

2. Description of the Related Art An ultraviolet curable coating agent containing an ultraviolet absorber is disclosed in JP-A-7-118564, is commercially available, and is well known.

[0003]

However, this coating composition does not have sufficient adhesion to the base, and it is necessary to use a primer for coating various substrates. Further, since the hardness of the coating material depends on the monomer used, it is difficult to adjust the hardness. Also,
Commercially available alcohol-soluble type coating agents lack water resistance.

The present invention does not block visible light at all.
A one-pack type UV shielding coating agent that effectively shields UV rays having a wavelength shorter than 0 nm, has excellent adhesion to a base material, durability, and can adjust the coating hardness according to the application. is there.

[0005]

The ultraviolet-shielding coating agent of the present invention has an organic binder and an effective absorption wavelength of 270.
It is a one-component type ultraviolet ray shielding coating agent composition containing an ultraviolet absorber having a wavelength of ˜380 nm, ultrafine white metal oxide, a fluororesin soluble in an organic solvent, and an acidic substance.

In addition to the organic binder, one of the features of the present invention is the combined use of a fluororesin soluble in an organic solvent, which imparts water resistance to the coating film.

The ultraviolet-shielding coating agent of the present invention comprises the organic binder 100 in the solid content weight ratio of the above components.
1 to 10 parts of ultraviolet absorber, 1 to 20 parts of ultrafine white metal oxide, 30 to 150 parts of fluororesin soluble in organic solvent, and 0.5 to 10 parts of acidic substance. It was done. A solvent is added to the components containing these to be distributed as a uniform solution, and further diluted with a solvent as required before being subjected to a coating step.

With regard to the constituent components, if the amount of the ultraviolet absorber is 1 part or less, the ultraviolet absorbing ability is insufficient, and even if 20 parts or more is added, the ultraviolet absorbing ability does not increase, and the cost becomes rather high. Even when the amount of the ultrafine white metal oxide added is 1 part or less, the ultraviolet ray shielding ability becomes insufficient, and when it is 20 parts or more, the shielding effect does not increase and the cost becomes high in this case as well. If the amount of the fluororesin added is 30 parts or less, the water resistance is not sufficient, and if it is 150 parts or more, the adhesion to the base material becomes problematic, and the applicable base material is limited.

Ultrafine particles of titanium oxide, zinc oxide, zirconium oxide and the like can be used as the white metal oxide, and titanium oxide is particularly preferable. Phosphoric acid is preferably used as the acidic substance. Although the action of phosphoric acid is not clear, it is considered that it contributes to the improvement of the adhesion to the base material. As the organic binder used in the UV-shielding coating agent of the present invention, it is also preferable to use a UV-curable resin, and particularly an oligomer that reacts with UV rays to have a high molecular weight and / or crosslinks is preferable in view of characteristics. .

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The UV-shielding coating agent of the present invention has an organic binder as a solvent and an effective absorption wavelength of 270 to 270.
380 nm ultraviolet absorber, ultrafine titanium oxide,
It can be obtained by dissolving and dispersing a component containing an organic solvent-soluble fluororesin and a one-pack type UV-shielding coating agent containing an acidic substance. Examples of the organic binder include polyurethane resin, polyacrylic acid ester-based resin or polymethacrylic acid ester-based resin, polyester resin, polyvinyl butyral resin, and the like, and it is particularly preferable to use a polymer or oligomer having a reactive acrylate group.

As the ultraviolet absorber used in the present invention, a compound having an effective absorption wavelength range of 270 to 380 nm is preferably used, and a benzotriazole compound is particularly preferable. Examples of such a benzotriazole-based ultraviolet absorber include 2- (2′-hydroxy-5′-
Methylphenyl) benzotriazole, 2- (2′-hydroxy-5′-t-butylphenyl) benzotriazole, 2- (2′-hydroxy-3 ′, 5′-di-t-
Butylphenyl) benzotriazole 2- (2'-hydroxy-3'-t-butyl-5'-methylphenyl)
-5-chlorobenzotriazole, 2- (2'-hydroxy-3 ', 5'-di-t-butylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-
3 ', 5'-di-t-amylphenyl) benzotriazole, 2- (2'-hydroxy-4'octoxyphenyl) benzotriazole, 2- {2'-hydroxy-
3 '-(3 ", 4", 5 ", 6" -tetrahydrophthalimidomethyl) -5'-methylphenyl} benzotriazole and the like.

In the present invention, a salicylate-based or benzophenone-based UV absorber can also be used. Examples of such salicylate-based or benzophenone-based ultraviolet absorbers include 2,4-di-t-butylphenyl-
3 ', 5'-di-t-butyl-4'-hydroxybenzoate, p-t-butylphenyl salicylate, 2,4
-Hydroxybenzophenone, 2-hydroxy-4-
Examples thereof include methoxybenzophenone and 2-hydroxy-4-n-octoxybenzophenone. These ultraviolet absorbers may be used alone or in combination of two or more.

In addition to these imidazole-based, salicylate-based, and benzophenone-based UV absorbers, it is also preferable to use a cyanoacrylate-based UV absorber in combination. Examples of the cyanoacrylate-based ultraviolet absorber include ethyl-2-cyano-3,3′-diphenyl acrylate and octyl-2-cyano-3,3′-diphenyl acrylate.

The ultrafine particle titanium oxide used in the present invention has a particle diameter of 300 nm or less, and particularly preferably 100 nm or less. Such fine particles transmit visible light but block ultraviolet light by light scattering.

As the solvent-soluble type fluororesin used in the present invention, commercially available clear type fluororesin paints can be used. Asahi Glass Co., Ltd., Dainippon Ink and Chemicals Co., Ltd., Nippon Paint Co., Ltd. ), Dainippon Paint Co., Ltd., etc.

As the acidic substance, a protonic acid and a Lewis acid can be used, and phosphoric acid is particularly preferable.

As the organic solvent used in the composition of the present invention, any one that can uniformly dissolve an organic binder, an ultraviolet absorber and a fluororesin can be used. Particularly, from the viewpoint of toxicity during use, ethanol, i- Propanol, n-, s
alcohols such as ec- and t-butanol, esters such as ethyl acetate, butyl acetate and ε-caprolactone,
It is preferable to use ketones such as MEK, MIBK and cyclohexanone, and aromatic hydrocarbons such as toluene and xylene.

In order to improve the dispersion of the titanium oxide,
It is preferable to use various coupling agents, and examples thereof include a silane coupling agent, a titanate coupling agent, and a zirconium coupling agent. It is also possible to use a surfactant together with or instead of these coupling agents.

The composition of the present invention is also preferably used in combination with various additives for the purpose of improving the adhesion to the substrate, and the coupling agent also has this effect. For example, the silane coupling agent contributes to the improvement of the adhesiveness with a substrate such as glass having an OH group on the surface.

The coating material of the present invention can be applied to a substrate by a known method such as spraying, brush coating, dipping, coating with a roll coater or knife coater.

[0021]

Embodiments of the present invention will be described below. (Example) Raw materials having the following composition were mixed and dissolved to obtain an ultraviolet shielding coating agent. Polyurethane lacquer Solid content 100 parts by weight 2- (2'-hydroxy-5'-methylphenyl) benzotriazole 5 parts by weight V Freon # 100 80 parts by weight as a fluorine resin (Dainippon Paint Co., Ltd.) Displayed) Phosphoric acid 1 part by weight Organic solvent n-butanol 60 parts by weight n-butyl acetate 70 parts by weight MIBK 70 parts by weight Toluene 100 parts by weight Biosorb 930 (joint chemical) 5 parts by weight (cyanoacrylate UV absorber)

The obtained paint was evaluated as follows. (Evaluation of UV shielding performance) A 2 mm hard glass plate was dipped in the obtained coating material to form a coating film having a surface of 15 μm on one side. About this glass plate, ultraviolet lamp (5W)
The shielding efficiency was measured by a UV tester using the light source as a light source. Measurement result

[0023]

[Table 1]

(Evaluation of coating film performance) A tin plate having a thickness of 0.2 mm was dipped in the coating material obtained in the example to prepare a coating film having a thickness of 20 μm. The coating film was evaluated after being left for 2 days at room temperature and dried. The results were as follows. Hardness 2H Adhesion (cross-cut test) 100/100 (no peeling) T-bending No cracks generated Solvent resistance (xylene) No change Water resistance (one day immersion) No change Salt water resistance (one day immersion) No change

A color photograph is coated with the coating material of the embodiment to a thickness of 15 μm.
Was exposed to sunlight (irradiation with an ultraviolet lamp?) For 3 months. No discoloration was observed in the coated one, but fading occurred in the uncoated one.

[0026]

As described above, according to the present invention, a coating agent is obtained which has no influence on the transmission of visible light and effectively shields ultraviolet rays having a wavelength of 380 nm or less, and at the same time has good adhesion to various substrates. be able to.

Claims (4)

[Claims] 1. An organic binder having an effective absorption wavelength of 270 to 270.
380 nm ultraviolet absorber, ultrafine titanium oxide,
A one-pack ultraviolet ray shielding coating composition containing an organic solvent-soluble fluororesin and an acidic substance. 2. Organic binder 100 in terms of solid content weight ratio.
1 to 10 parts of ultraviolet absorber, 1 to 20 parts of ultrafine white metal oxide, 30 to 150 parts of fluororesin soluble in organic solvent, and 0.5 to 10 parts of acidic substance. The one-pack ultraviolet ray-shielding coating agent composition according to claim 1. 3. The one-pack ultraviolet ray shielding coating composition according to claim 1, wherein the acidic substance is phosphoric acid. 4. An ultraviolet curable resin having an effective absorption wavelength of 270.
A one-pack ultraviolet shielding coating composition containing an ultraviolet absorber having a wavelength of ˜380 nm, ultrafine titanium oxide, a fluororesin soluble in an organic solvent, and an acidic substance.