Photocatalyst article, anti-fogging, anti-soiling articles, and production method of anti-fogging, anti-soiling articles

• US 6,576,344 B1
• Filed: 05/24/2000
• Issued: 06/10/2003
• Est. Priority Date: 09/30/1998
• Status: Expired due to Fees

• Current Assignee: Nippon Sheet Glass Company Limited
• Original Assignee: Nippon Sheet Glass Company Limited
• Inventors: Inomata, Hiroyuki, Doushita, Kazuhiro
• Primary Examiner(s): Jones, Deborah
• Assistant Examiner(s): STEIN, STEPHEN J
• Application Number:
  US09/577,299
• Time in Patent Office: 1,112 Days
• Field of Search: 428/426, 428/428, 428/432, 428/429, 428/446, 428/447, 428/448, 428/701, 428/702, 501/134, 501/154
• US Class Current: 428/426
• CPC Class Codes: B01J 35/30 characterised by their physical properties
• CPC Class Codes: B01J 35/39 Photocatalytic properties
• CPC Class Codes: C03C 17/007 containing a dispersed phase, e.g. particles, fibres or flakes, in a continuous phase
• CPC Class Codes: C03C 17/23 Oxides C03C17/02 takes precedence
• CPC Class Codes: C03C 17/3411 with at least two coatings of inorganic materials C03C17/36, C03C17/42 take precedence
• CPC Class Codes: C03C 2217/23 Mixtures
• CPC Class Codes: C03C 2217/45 Inorganic continuous phases
• CPC Class Codes: C03C 2217/477 Titanium oxide
• CPC Class Codes: C03C 2217/71 Photocatalytic coatings
• CPC Class Codes: Y10T 428/252 Glass or ceramic [i.e., fired or glazed clay, cement, etc.] [porcelain, quartz, etc.]
• CPC Class Codes: Y10T 428/265 1 mil or less

Abstract

A photocatalyst article exhibits high photocatalytic activity even in environments illuminated by weak ultraviolet light or visible light, expresses excellent anti-fogging and anti-soiling properties, and retains good anti-fogging and anti-soiling performance over long periods and therefore has a high utilization value as an anti-fogging, anti-soiling article. The photocatalyst article contains an oxide semiconductor and a compound which contains at least one type of element selected from the group comprised of Mg, Sc, V, Cr, Mn, Y, Nb, Mo, Ru, W, and Re, at a content such that the ratio (A/B) of the number of metal atoms of the abovementioned element (A) to the number of atoms of metal that comprise the abovementioned oxide semiconductor (B) will be about 0.20 to 2.

Claims

1. A photocatalyst article consisting of a metallic compound containing at least one type of element (A) selected from the group consisting of:

magnesium, scandium, vanadium, chromium, manganese, yttrium, niobium, molybdenum, ruthenium, tungsten, and rhenium; and

a metal oxide semiconductor (B);

at a content whereby the ratio (A/B) of the number of metal atoms of said element (A) to the number of atoms of metal that comprise said metal oxide semiconductor (B) is 0.20 to 2.

3. The photocatalyst article as set forth in claim 1 or 2, wherein said oxide semiconductor is titanium oxide microparticles.

4. The photocatalyst article as set forth in claim 3, wherein said titanium oxide microparticles have an average particle diameter of 2 to 120 nm.

5. The photocatalyst article as set forth in claim 1, wherein said at least one type of element is selected from the group comprised of vanadium, niobium, and molybdenum.

2. A photocatalyst article consisting of a metallic compound containing at least one type of element (A) selected from the group consisting of:

magnesium, scandium, vanadium, chromium, manganese, yttrium, niobium, molybdenum, ruthenium, tungsten, and rhenium; and

a metal oxide semiconductor (B);

at a content whereby the ratio (A/B) of the number of metal atoms of said element (A) to the number of atoms of metal that comprise said metal oxide semiconductor (B) is 0.20 to 2; and

10 to 80 weight % of silicon oxide.

6. An anti-fogging, anti-soiling article comprising a thin film formed on a substrate surface, the thin film consisting of:

(1) a compound, containing at least one type of element (A) selected from the group consisting of;

magnesium, scandium, vanadium, chromium, manganese, yttrium, niobium, molybdenum, ruthenium, tungsten, and rhenium, and

(2) a metal oxide semiconductor (B);

wherein the content ratio (A/B) of the number of metal atoms of said element (A) to the number of atoms of metal that comprises said metal oxide semiconductor (B) is 0.20 to 2.

8. The anti-fogging, anti-soiling article as set forth in claim 6 or 7, wherein said oxide semiconductor is titanium oxide microparticles.

9. The anti-fogging, anti-soiling article as set forth in claim 8, wherein said titanium oxide microparticles have an average particle diameter of 2 to 120 nm.

10. The anti-fogging, anti-soiling article as set forth in claim 6, wherein said at least one type of element is selected from the group consisting of:

vanadium, niobium, and molybdenum.

11. The anti-fogging, anti-soiling article as set forth in claim 6, wherein said thin film has a thickness of 2 to 500 nm.

12. The anti-fogging, anti-soiling article as set forth in claim 6, wherein said substrate is glass.

13. The anti-fogging, anti-soiling article as set forth in claim 12, wherein said substrate is glass with an alkali-blocking film.

14. The anti-fogging, anti-soiling article as set forth in claim 13, wherein said alkali-blocking film is comprised of at least one type of metal oxide selected from the group consisting of:

silicon oxide, aluminum oxide, titanium oxide, zirconium oxide, and cerium oxide.

15. The anti-fogging, anti-soiling article as set forth in claim 13 or 14, wherein said alkali-blocking film is a film having silicon oxide as the main component thereof.

16. The anti-fogging, anti-soiling article as set forth in claim 13, wherein said alkali-blocking film has a thickness of 5 to 300 nm.

17. The anti-fogging, anti-soiling article as set forth in claim 6, wherein an overcoat layer, comprised of at least one type of metal oxide selected from the group consisting of:

silicon oxide, aluminum oxide, titanium oxide, zirconium oxide; and

cerium oxide, is formed on top of said thin film.

18. The anti-fogging, anti-soiling article as set forth in claim 17, wherein said overcoat layer has silicon oxide as the main component.

19. The anti-fogging, anti-soiling article as set forth in claim 17 or 18, wherein said overcoat layer has an average thickness of 0.1 to 50 nm.

20. The anti-fogging, anti-soiling article as set forth in claim 17, wherein said overcoat layer is a porous body with a porosity of 1 to 50%.

21. The anti-fogging, anti-soiling article as set forth in claim 17, wherein said overcoat layer contains silica microparticles at a content of 5 to 80 weight %.

22. The anti-fogging, anti-soiling article as set forth in claim 21, wherein at least part of said silica microparticles are chain-like silica microparticles.

23. The anti-fogging, anti-soiling article as set forth in claim 22, wherein said chain-like silica microparticles have a diameter of 10 to 20 nm and a length of 40 to 300 nm.

24. The anti-fogging, anti-soiling article as set forth in claim 6, wherein an organic substance adhesion prevention layer is formed on top of said thin film or on top of said overcoat layer.

25. The anti-fogging, anti-soiling article as set forth in claim 24, wherein said organic substance adhesion prevention layer is comprised of a silicon oxide layer or an organosilane, which contains at least one type of functional group selected from the group consisting of:

polyalkylene oxide groups, alkyl groups, alkenyl groups, and aryl groups in the molecule, or a hydrolysate of such an organosilane.

26. The anti-fogging, anti-soiling article as set forth in claim 24 or 25, wherein said organic substance adhesion prevention layer has an average of 0.5 to 5 molecular layers in the thickness direction.

7. An anti-fogging, anti-soiling article comprising a thin film formed on a substrate surface, the thin film consisting of:

(1) a compound, containing at least one element (A) selected from the group consisting of;

magnesium, scandium, vanadium, chromium, manganese, yttrium, niobium, molybdenum, ruthenium, tungsten, and rhenium; and

,

(2) a metal oxide semiconductor (B),

wherein the content ratio (A/B) of the number of metal atoms of said element (A) to the number of atoms of metal that comprise said metal oxide semiconductor (B) is 0.20 to 2; and

,

(3) 10 to 80 weight % of silicon oxide.