VISIBLE-LIGHT-RESPONSIVE TITANIUM OXIDE MICROPARTICLE DISPERSION, AND PROCESS FOR PRODUCTION THEREOF

• US 20120214667A1
• Filed: 03/11/2011
• Published: 08/23/2012
• Est. Priority Date: 05/18/2010
• Status: Active Grant

• Current Assignee: Shin-Etsu Chemical Company Limited
• Original Assignee: Shin-Etsu Chemical Company Limited
• Inventors: Furudate, Manabu, Inoue, Tomohiro, Amano, Tadashi, Eguchi, Yoshitsugu
• Granted Patent: US 8,986,580 B2
• Time in Patent Office: Days
• US Class Current: 502/350
• CPC Class Codes: B01J 21/063 Titanium; Oxides or hydroxides thereof
• CPC Class Codes: B01J 23/835 with germanium, tin or lead
• CPC Class Codes: B01J 35/39 Photocatalytic properties
• CPC Class Codes: B01J 35/393 Metal or metal oxide crystallite size
• CPC Class Codes: B01J 35/51 Spheres
• CPC Class Codes: B01J 37/031 Precipitation
• CPC Class Codes: B01J 37/10 in the presence of water, e.g. steam
• CPC Class Codes: C01G 23/047 Titanium dioxide
• CPC Class Codes: C01P 2004/04 obtained by TEM, STEM, STM or AFM
• CPC Class Codes: C01P 2006/60 Optical properties, e.g. expressed in CIELAB-values
• CPC Class Codes: C09C 1/3653 Treatment with inorganic compounds
• CPC Class Codes: Y10T 428/2991 Coated

Abstract

Disclosed are: a visible-light-responsive titanium oxide microparticle dispersion comprising an aqueous dispersion medium and titanium oxide microparticles dispersed therein, and a peroxotitanium component, an iron component and/or a copper component and a tin component, wherein the content of the peroxotitanium component is 0.1 to 20 mass % relative to the titanium oxide content; and a process for producing a visible-light-responsive titanium oxide microparticle dispersion, comprising (1) producing peroxotitanic acid containing a tin compound from a raw material titanium compound, a tin compound and hydrogen peroxide, (2) heating an aqueous solution of peroxotitanic acid containing the tin compound to 80 to 250° C. under a high pressure to produce a titanium oxide microparticle dispersion containing a peroxotitanium component and a tin component, and (3) adding an iron compound and/or a copper compound to the titanium oxide microparticle dispersion to cause a reaction between the iron compound and/or the copper compound with the dispersion.

Claims

1. A visible-light-responsive titanium oxide microparticle dispersion comprising an aqueous dispersion solvent and titanium oxide microparticles dispersed in the aqueous dispersion solvent and additionally comprising a peroxotitanium component, a tin component, and an iron component and/or a copper component, wherein the content of the peroxotitanium component is 0.1 to 20 wt % based on titanium oxide.

2. The visible-light-responsive titanium oxide microparticle dispersion according to claim 1, wherein the content of the iron component in terms of metal iron is 0.01 to 5 wt % based on titanium oxide.

3. The visible-light-responsive titanium oxide microparticle dispersion according to claim 1, wherein the content of the copper component in terms of metal copper is 0.01 to 5 wt % based on titanium oxide.

4. The visible-light-responsive titanium oxide microparticle dispersion according to any one of claims 1 to 3, wherein the content of the tin component in terms of molar ratio (Ti/Sn) between the tin component and titanium oxide is from 1 to 1000.

5. The visible-light-responsive titanium oxide microparticle dispersion according to claim 1, wherein the titanium oxide microparticles have a 50% cumulative distribution diameter (D₅₀) measured by a dynamic scattering method of not more than 50 nm.

6. A process for producing the visible-light-responsive titanium oxide microparticle dispersion according to claim 1, comprising the steps of:

(1) producing an aqueous solution of peroxotitanic acid containing a tin compound from a raw material titanium compound, a tin compound and hydrogen peroxide;

(2) heating the aqueous solution of peroxotitanic acid containing the tin compound to 80 to 250°

C. under a high pressure to produce a titanium oxide microparticle dispersion containing a peroxotitanium component and a tin component; and

(3) adding an iron compound and/or a copper compound to the titanium oxide microparticle dispersion to cause a reaction of the iron compound and/or the copper compound with the dispersion.