PHOTOCATALYST DISPERSION LIQUID AND PROCESS FOR PRODUCING THE SAME

• US 20090305879A1
• Filed: 06/04/2009
• Published: 12/10/2009
• Est. Priority Date: 06/05/2008
• Status: Abandoned Application

• Current Assignee: Sumitomo Chemical Company Limited
• Original Assignee: Sumitomo Chemical Company Limited
• Inventors: SAKATANI, Yoshiaki, Murata, Makoto, Okusako, Kensen
• Application Number:
  US12/478,079
• Publication Number:
  US 20090305879A1
• Time in Patent Office: Days
• US Class Current: 502/210
• CPC Class Codes: B01D 2255/1021 Platinum
• CPC Class Codes: B01D 2255/1023 Palladium
• CPC Class Codes: B01D 2255/104 Silver
• CPC Class Codes: B01D 2255/106 Gold
• CPC Class Codes: B01D 2255/20707 Titanium
• CPC Class Codes: B01D 2255/20776 Tungsten
• CPC Class Codes: B01D 2255/802 Photocatalytic
• CPC Class Codes: B01D 2257/306 Organic sulfur compounds, e.g. mercaptans
• CPC Class Codes: B01D 2257/40 Nitrogen compounds
• CPC Class Codes: B01D 2257/406 Ammonia
• CPC Class Codes: B01D 2257/708 Volatile organic compounds V.O.C.'s
• CPC Class Codes: B01D 2257/90 Odorous compounds not provided for in groups B01D2257/00 - B01D2257/708
• CPC Class Codes: B01D 2257/91 Bacteria; Microorganisms
• CPC Class Codes: B01D 2259/802 Visible light
• CPC Class Codes: B01D 2259/804 UV light
• CPC Class Codes: B01D 53/8687 Organic components
• CPC Class Codes: B01J 21/063 Titanium; Oxides or hydroxides thereof
• CPC Class Codes: B01J 23/30 Tungsten
• CPC Class Codes: B01J 23/6527 Tungsten
• CPC Class Codes: B01J 23/687 with tungsten
• CPC Class Codes: B01J 27/188 : with chromium, molybdenum, tungsten or polonium
• CPC Class Codes: B01J 35/0013 : Colloids
• CPC Class Codes: B01J 35/004 : Photocatalysts
• CPC Class Codes: B01J 35/023 : Catalysts characterised by dimensions, e.g. grain size
• CPC Class Codes: B01J 35/1009 : less than 10 m2/g
• CPC Class Codes: B01J 35/1014 : 10-100 m2/g
• CPC Class Codes: B01J 35/1019 : 100-500 m2/g
• CPC Class Codes: B01J 35/23 : in a colloidal state
• CPC Class Codes: B01J 35/39 : Photocatalytic properties
• CPC Class Codes: B01J 35/40 : characterised by dimensions, e.g. grain size in a colloidal state B01J35/23; crystallite size B01J35/77
• CPC Class Codes: B01J 35/612 : less than 10 m2/g
• CPC Class Codes: B01J 35/613 : 10-100 m2/g
• CPC Class Codes: B01J 35/615 : 100-500 m2/g
• CPC Class Codes: B01J 37/0211 : using a colloidal suspension
• CPC Class Codes: B01J 37/0215 : Coating
• CPC Class Codes: B01J 37/0219 : the coating containing organic compounds
• CPC Class Codes: B01J 37/345 : of ultraviolet wave energy
• CPC Class Codes: C04B 14/30 : Oxides other than silica ferrites C04B14/363
• CPC Class Codes: C04B 14/305 : Titanium oxide, e.g. titanates
• CPC Class Codes: C04B 2111/00482 : Coating or impregnation materials
• CPC Class Codes: C04B 2111/00525 : for metallic surfaces
• CPC Class Codes: C04B 2111/00827 : Photocatalysts; materials containing photocatalysts to avoid staining by air pollutants C04B2111/2061
• CPC Class Codes: C04B 2111/2061 : Materials containing photocatalysts, e.g. TiO2, for avoiding staining by air pollutants or the like
• CPC Class Codes: C04B 22/16 : containing phosphorus in the anion, e.g. phosphates
• CPC Class Codes: C04B 22/165 : Acids
• CPC Class Codes: C04B 26/00 : Compositions of mortars, concrete or artificial stone, containing only organic binders , e.g. polymer or resin concrete mechanical aspects of moulding polymer or resin concrete B29C67/242
• CPC Class Codes: C04B 28/00 : Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements
• CPC Class Codes: C04B 41/4539 : as a emulsion, dispersion or suspension
• CPC Class Codes: C04B 41/5041 : Titanium oxide or titanates
• CPC Class Codes: C04B 41/5072 : with oxides or hydroxides not covered by C04B41/5025 C04B40/0236 takes precedence; boron oxide C04B41/5006
• CPC Class Codes: C04B 41/5092 : Phosphate cements
• CPC Class Codes: C09D 1/00 : Coating compositions, e.g. paints, varnishes or lacquers, based on inorganic substances

Abstract

A photocatalyst dispersion liquid contains titanium oxide particles, tungsten oxide particles, a phosphoric acid (salt) and a dispersion medium, and a containing amount of the phosphoric acid (salt) is from 0.001 mol times to 0.2 mol times with respect to the titanium oxide particles. In this photocatalyst dispersion liquid, the aggregation of the particles is suppressed and thus solid-liquid separation is not easily generated. According to this process for producing a photocatalyst dispersion liquid, titanium oxide particles are dispersed in a dispersion medium containing a phosphoric acid (salt) dissolved therein to obtain a titanium oxide particle dispersion liquid, and then tungsten oxide particles are mixed in the titanium oxide particle dispersion liquid.

Claims

1. A photocatalyst dispersion liquid comprising titanium oxide particles, tungsten oxide particles, a phosphoric acid (salt) and a dispersion medium, wherein a containing amount of the phosphoric acid (salt) is from 0.001 mol times to 0.2 mol times with respect to the titanium oxide particles.

2. The photocatalyst dispersion liquid according to claim 1, which further comprises an electron-withdrawing substance or its precursor.

3. The photocatalyst dispersion liquid according to claim 2, wherein the electron-withdrawing substance or its precursor contains one or more atoms of metal selected from the group consisting of Cu, Pt, Au, Pd, Ag, Fe, Nb, Ru, Ir, Rh and Co.

4. The photocatalyst dispersion liquid according to claim 2, wherein a containing amount of the electron-withdrawing substance or its precursor is from 0.005 parts by mass to 0.6 parts by mass in terms of the metal atom with respect to 100 parts by mass of the total amount of the titanium oxide particles and the tungsten oxide particles.

5. The photocatalyst dispersion liquid according to claim 1, wherein the phosphoric acid (salt) is selected from the group consisting of phosphoric acid, ammonium phosphate, sodium phosphate and potassium phosphate.

6. The photocatalyst dispersion liquid according to claim 1, wherein an average dispersed particle diameter of the titanium oxide particles is from 20 nm to 150 nm.

7. The photocatalyst dispersion liquid according to claim 1, wherein the BET specific surface area of the titanium oxide particles is from 100 m²/g to 500 m²/g.

8. The photocatalyst dispersion liquid according to claim 1, wherein an average dispersed particle diameter of the tungsten oxide particles is from 50 nm to 200 nm.

9. The photocatalyst dispersion liquid according to claim 1, wherein the BET specific surface area of the tungsten oxide particles is from 5 m²/g to 100 m²/g.

10. The photocatalyst dispersion liquid according to claim 1, wherein a mass ratio of the titanium oxide particles and the tungsten oxide particles is from 4:

1 to 1;

8.

11. The photocatalyst dispersion liquid according to claim 1, wherein a mass of the dispersion medium is from 5 times to 200 times with respect to the total mass of the titanium oxide particles and the tungsten oxide particles.

12. The photocatalyst dispersion liquid according to claim 1, wherein a hydrogen ion concentration thereof is a pH value of 2.0 to 7.0.

19. A photocatalyst functional product comprising a photocatalyst layer on a surface, wherein the photocatalyst layer is formed using the photocatalyst dispersion liquid according to claim 1.

13. A process for producing a photocatalyst dispersion liquid, the process comprising steps of

dispersing titanium oxide particles in a dispersion medium containing a phosphoric acid (salt) dissolved therein to obtain a titanium oxide particle dispersion liquid;

and

mixing tungsten oxide particles in the titanium oxide particle dispersion liquid.

14. The process for producing a photocatalyst dispersion liquid according to claim 13, wherein the tungsten oxide particles are dispersed in a dispersion medium to obtain a tungsten oxide particle dispersion liquid, and then the tungsten oxide particle dispersion liquid is mixed with the titanium oxide particle dispersion liquid.

15. The process for producing a photocatalyst dispersion liquid according to claim 13, which further comprises a step of adding an electron-withdrawing substance or its precursor.

16. The process for producing a photocatalyst dispersion liquid according to claim 14, wherein the electron-withdrawing substance or its precursor is added in the tungsten oxide particle dispersion liquid.

17. The process for producing a photocatalyst dispersion liquid according to claim 15, which further comprises a step of a light irradiation after the precursor of the electron-withdrawing substance is added.

18. The process for producing a photocatalyst dispersion liquid according to claim 17, wherein the light irradiation is carried out before the tungsten oxide particles are mixed in the titanium oxide particle dispersion liquid.