Coating composition of photocatalyst

• US 20050233893A1
• Filed: 03/16/2005
• Published: 10/20/2005
• Est. Priority Date: 03/17/2004
• Status: Active Grant

• Current Assignee: Asahi Chemical Co. Ltd. (Sumitomo Chemical Company Limited), Sumitomo Chemical Company Limited
• Original Assignee: Asahi Chemical Co. Ltd. (Sumitomo Chemical Company Limited), Sumitomo Chemical Company Limited
• Inventors: Sakaguchi, Seiichi, Sakatani, Yoshiaki
• Granted Patent: US 7,521,391 B2
• Time in Patent Office: Days
• US Class Current: 502/150
• CPC Class Codes: B01J 35/39 Photocatalytic properties
• CPC Class Codes: B01J 37/0215 Coating
• CPC Class Codes: C03C 17/256 Coating containing TiO2
• CPC Class Codes: C03C 2217/212 TiO2
• CPC Class Codes: C03C 2217/213 SiO2
• CPC Class Codes: C03C 2217/22 ZrO2
• CPC Class Codes: C03C 2217/71 Photocatalytic coatings
• CPC Class Codes: C03C 2218/113 by sol-gel processes

Abstract

A photocatalytic coating composition comprising a photocatalyst, a silicon alkoxide, a zirconium compound, colloidal silica, and a liquid medium, wherein a content of the zirconium compound in terms of zirconium atoms is 0.3 to 3 times by mole a content of the silicon alkoxide in terms of silicon atoms, which can form a coating film of a photocatalyst with a high adhesion strength to a substrate.

Claims

1. A photocatalytic coating composition comprising a photocatalyst, a silicon alkoxide, a zirconium compound, colloidal silica, and a liquid medium, wherein a content of the zirconium compound in terms of zirconium atoms is 0.3 to 3 times by mole a content of the silicon alkoxide in terms of silicon atoms.

2. The photocatalytic coating composition according to claim 1, wherein a content of colloidal silica in terms of silicon oxide is 1 to 200 parts by weight per 100 parts by weight of the silicon alkoxide in terms of silicon oxide, and the total content of the silicon alkoxide, the zirconium compound and colloidal silica in terms of the oxides is 5 to 200 parts by weight of the photocatalyst.

3. The photocatalytic coating composition according to claim 1, which further comprises a chelating agent.

4. The photocatalytic coating composition according to claim 3, wherein the amount of the chelating agent is 1 to 40 times by mole the content of the zirconium compound in terms of zirconium atoms.

5. The photocatalytic coating composition according to claim 1, which contains at least 0.1% by weight of the photocatalyst based on the whole weight of the coating composition.

6. The photocatalytic coating composition according to claim 1, wherein the photocatalyst comprises titanium oxide.

7. The photocatalytic coating composition according to claim 1, wherein the liquid medium comprises an organic solvent.