Substrate with a photocatalytic coating based on titanium dioxide and organic dispersions based on titanium dioxide

• US 6,362,121 B1
• Filed: 01/21/2000
• Issued: 03/26/2002
• Est. Priority Date: 09/15/1995
• Status: Expired due to Term

• Current Assignee: Saint-Gobain Vitrage, Rhodia Chimie (Solvac SA)
• Original Assignee: Saint-Gobain Vitrage, Rhodia Chimie (Solvac SA)
• Inventors: Talpaert, Xavier, Dupuis, Dominique, Chopin, Thierry, Lehaut, Corinne, Chartier, Pascal
• Primary Examiner(s): Lovering, Richard D.
• Application Number:
  US09/488,760
• Time in Patent Office: 795 Days
• Field of Search: 252/588, 516/33, 106/287.16, 106/287.17, 501/12, 427/160, 427/168, 427/169, 427/376.2, 502/2, 502/351, 502/522, 264/DIG.25
• US Class Current: 502/2
• CPC Class Codes: B01J 35/30 characterised by their physical properties
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: C01G 23/047 Titanium dioxide
• CPC Class Codes: C01P 2002/02 Amorphous compounds
• CPC Class Codes: C01P 2002/50 Solid solutions
• CPC Class Codes: C01P 2004/64 Nanometer sized, i.e. from 1-100 nanometer
• CPC Class Codes: C01P 2004/86 Thin layer coatings, i.e. the coating thickness being less than 0.1 time the particle radius
• CPC Class Codes: C01P 2006/60 Optical properties, e.g. expressed in CIELAB-values
• CPC Class Codes: C01P 2006/82 water content
• CPC Class Codes: C03C 17/007 containing a dispersed phase, e.g. particles, fibres or flakes, in a continuous phase
• CPC Class Codes: C03C 17/008 comprising a mixture of materials covered by two or more of the groups C03C17/02, C03C17/06, C03C17/22 and C03C17/28
• CPC Class Codes: C03C 17/2456 Coating containing TiO2
• CPC Class Codes: C03C 17/256 Coating containing TiO2
• CPC Class Codes: C03C 2217/212 TiO2
• CPC Class Codes: C03C 2217/29 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: C03C 8/20 containing titanium compounds; containing zirconium compounds
• CPC Class Codes: C04B 41/5041 Titanium oxide or titanates
• CPC Class Codes: C04B 41/52 : Multiple coating or impregnating multiple coating or impregnating with the same composition or with compositions only differing in the concentration of the constituents, is classified as single coating or impregnation
• CPC Class Codes: C09D 1/00 : Coating compositions, e.g. paints, varnishes or lacquers, based on inorganic substances
• CPC Class Codes: C09D 17/008 : Titanium dioxide
• CPC Class Codes: C23C 18/1216 : Metal oxides C23C18/1212 takes precedence
• CPC Class Codes: C23C 18/1225 : Deposition of multilayers of inorganic material
• CPC Class Codes: C23C 18/1245 : Inorganic substrates other than metallic
• CPC Class Codes: C23C 18/1254 : Sol or sol-gel processing
• CPC Class Codes: C23C 18/1258 : Spray pyrolysis
• CPC Class Codes: C23C 18/127 : Preformed particles
• CPC Class Codes: C23C 18/1295 : with after-treatment of the deposited inorganic material
• CPC Class Codes: C23C 26/00 : Coating not provided for in groups C23C2/00 - C23C24/00
• CPC Class Codes: C23C 30/00 : Coating with metallic material characterised only by the composition of the metallic material, i.e. not characterised by the coating process C23C26/00, C23C28/00 take precedence
• CPC Class Codes: Y02T 50/60 : Efficient propulsion technologies, e.g. for aircraft
• CPC Class Codes: Y10S 502/522 : Radiant or wave energy activated

Abstract

The invention relates to a substrate provided, on at least a portion of one of its faces, with a coating with a photocatalytic property based on titanium dioxide which is at least partially crystalline and which is incorporated in the said coating partly in the form of particles predominantly crystallized in the anatase form. The invention also relates to a process for the preparation of this substrate and organic dispersions of titanium dioxide particles used in the said process for the preparation of the substrate.

Claims

1. A substrate provided, on at least a portion of one of its faces, with a coating with a photocatalytic property based on titanium dioxide which exhibits an external hydrophilic surface, which is at least partially crystalline and which is incorporated in said coating partly in the form of particles predominantly crystallized in the anatase form, said particles being incorporated in the coating using an inorganic binder in the form of an amorphous or partially crystalline silicon oxide or a mixture of oxides comprising silicon oxides.

2. A substrate according to claim 1, wherein the inorganic binder further contains an amorphous or partly crystalline titanium oxide.

3. A substrate according to claim 2, wherein said substrate is based on glass, ceramic or vitroceramic.

4. A substrate according to claim 2, wherein the substrate is an architectural material.

5. A substrate according to claim 1, wherein the substrate is an architectural material.

6. A process for producing a substrate according to claim 1, comprising the step of depositing and heat treating the coating from a dispersion containing at least one organometallic silicon compound of formula R_nSi(OR′

)p, wherein p is between 1 and 4, n=4−

p, R is a C₁ to C₁₈ alkyl radical, and R′

is a C₁-C₄ alkyl radical.

7. A substrate according to claim 1, wherein the coating exhibits a refractive index of between 1.40 and 2.35.

8. A substrate according to claim 1, wherein said substrate is based on glass, ceramic or vitroceramic.

9. A substrate according to claim 1, wherein at least one thin layer with an anti-static, thermal or optical function or forming a barrier to the migration of alkali metals originating from the substrate, is arranged under the coating based on titanium dioxide.

10. A substrate according to claim 1, wherein the coating constitutes the final layer of a stack of anti-glare layers.

11. A monolithic glazing or multiple glazing of the double glazing or laminated type incorporating a substrate according to claim 1.

12. A substrate provided, on at least a portion of one of its faces, with a coating with a photocatalytic property based on titanium dioxide which exhibits an external hydrophilic surface, which is at least partially crystalline and which is incorporated in said coating partly in the form of particles predominantly crystallized in the anatase form, said particles being incorporated in the coating using an inorganic binder, in the form of an amorphous or partially crystalline titanium oxide or a mixture of oxides comprising titanium oxide.

13. A substrate according to claim 12, wherein the substrate is an architectural material.

14. A substrate according to claim 12, wherein at least one thin layer with an anti-static, thermal or optical function or forming a barrier to the migration of alkali metals originating from the substrate, is arranged under the coating based on titanium dioxide.

15. A substrate according to claim 12, wherein said substrate is based on glass, ceramic or vitroceramic.

16. A substrate provided, on at least a portion of one of its faces, with a coating with a photocatalytic property based on titanium dioxide which exhibits an external hydrophilic surface, which is at least partially crystalline and which is incorporated in said coating partly in the form of particles predominantly crystallized in the anatase form, said particles being incorporated in the coating using an inorganic binder, in the form of an amorphous or partially crystalline zirconium oxide or a mixture of oxides comprising zirconium oxide.

17. A substrate according to claim 16, wherein the substrate is an architectural material.

18. A substrate according to claim 16, wherein at least one thin layer with an anti-static, thermal or optical function or forming a barrier to the migration of alkali metals originating from the substrate, is arranged under the coating based on titanium dioxide.

19. A substrate according to claim 16, wherein said substrate is based on glass, ceramic or vitroceramic.

20. A substrate provided, on at least a portion of one of its faces, with a coating with a photocatalytic property based on titanium dioxide which exhibits an external oleophilic surface, which is at least partially crystalline and which is incorporated in said coating partly in the form of particles predominantly crystallized in the anatase form, said particles being incorporated in the coating using an inorganic binder in the form of an amorphous or partially crystalline silicon oxide or a mixture of oxides comprising silicon oxides.

21. A substrate provided, on at least a portion of one of its faces, with a coating with a photocatalytic property based on titanium dioxide which exhibits an external oleophilic surface, which is at least partially crystalline and which is incorporated in said coating partly in the form of particles predominantly crystallized in the anatase form, said particles being incorporated in the coating using an inorganic binder, in the form of an amorphous or partially crystalline titanium oxide or a mixture of oxides comprising titanium oxide.

22. A substrate provided, on at least a portion of one of its faces, with a coating with a photocatalytic property based on titanium dioxide which exhibits an external oleophilic surface, which is at least partially crystalline and which is incorporated in said coating partly in the form of particles predominantly crystallized in the anatase form, said particles being incorporated in the coating using an inorganic binder, in the form of an amorphous or partially crystalline zirconium oxide or a mixture of oxides comprising zirconium oxide.