Substrate with a photocatalytic coating

• US 7,309,664 B1
• Filed: 06/10/1999
• Issued: 12/18/2007
• Est. Priority Date: 06/10/1998
• Status: Expired due to Fees

• Current Assignee: Saint-Gobain Recherche
• Original Assignee: Saint-Gobain Recherche
• Inventors: Marzolin, Christian, Marchal, Arnaud, Talpaert, Xavier
• Primary Examiner(s): TORRES VELAZQUEZ, NORCA LIZ
• Application Number:
  US09/719,153
• Time in Patent Office: 3,113 Days
• Field of Search: 442/97, 442/101, 442/117, 442/120, 428/292, 428/429, 428/433, 428/905
• US Class Current: 442/97
• CPC Class Codes: B01D 2255/802 Photocatalytic
• CPC Class Codes: B01D 2257/90 Odorous compounds not provided for in groups B01D2257/00 - B01D2257/708
• CPC Class Codes: B01D 53/8668 Removing organic compounds not provided for in B01D53/8603 - B01D53/8665
• CPC Class Codes: B01D 53/885 Devices in general for catalytic purification of waste gases
• CPC Class Codes: B01J 35/30 characterised by their physical properties
• CPC Class Codes: B01J 35/39 Photocatalytic properties
• CPC Class Codes: C03C 2217/71 Photocatalytic coatings
• CPC Class Codes: C03C 25/26 Macromolecular compounds or prepolymers
• CPC Class Codes: C03C 25/42 Coatings containing inorganic materials
• CPC Class Codes: C03C 25/47 containing particles, fibres or flakes, e.g. in a continuous phase
• CPC Class Codes: C04B 2111/50 Flexible or elastic materials
• CPC Class Codes: C04B 2111/52 Sound-insulating materials
• CPC Class Codes: C04B 30/02 containing fibrous materials
• CPC Class Codes: C04B 41/0072 Heat treatment
• CPC Class Codes: C04B 41/009 characterised by the material treated
• CPC Class Codes: C04B 41/4535 applied as a solution, emulsion, dispersion or suspension
• CPC Class Codes: C04B 41/48 Macromolecular compounds
• CPC Class Codes: C04B 41/4922 applied to the substrate as monomers, i.e. as organosilanes RnSiX4-n, e.g. alkyltrialkoxysilane, dialkyldialkoxysilane
• CPC Class Codes: C04B 41/5041 Titanium oxide or titanates
• CPC Class Codes: Y10S 428/905 Odor releasing material
• CPC Class Codes: Y10T 428/249924 : Noninterengaged fiber-containing paper-free web or sheet which is not of specified porosity
• CPC Class Codes: Y10T 428/31612 : As silicone, silane or siloxane
• CPC Class Codes: Y10T 442/2311 : Coating or impregnation is a lubricant or a surface friction reducing agent other than specified as improving the "hand" of the fabric or increasing the softness thereof
• CPC Class Codes: Y10T 442/2344 : Coating or impregnation is anti-slip or friction-increasing other than specified as an abrasive
• CPC Class Codes: Y10T 442/2402 : Coating or impregnation specified as a size
• CPC Class Codes: Y10T 442/2475 : Coating or impregnation is electrical insulation-providing, -improving, or -increasing, or conductivity-reducing
• CPC Class Codes: Y10T 442/25 : Coating or impregnation absorbs sound
• CPC Class Codes: Y10T 442/2738 : Coating or impregnation intended to function as an adhesive to solid surfaces subsequently associated therewith
• CPC Class Codes: Y10T 442/2992 : Coated or impregnated glass fiber fabric
• CPC Class Codes: Y10T 442/60 : Nonwoven fabric [i.e., nonwoven strand or fiber material]
• CPC Class Codes: Y10T 442/603 : Including strand or fiber material precoated with other than free metal or alloy
• CPC Class Codes: Y10T 442/604 : Strand or fiber material is glass
• CPC Class Codes: Y10T 442/605 : Strand or fiber material is inorganic
• CPC Class Codes: Y10T 442/699 : Including particulate material other than strand or fiber material

Abstract

A substrate, its process of manufacture, and its applications. The substrate includes a fibrous material which is provided, over at least a portion of its surface and/or within its thickness, with a coating with photocatalytic properties including a semi-conducting material with photocatalytic properties of the oxide or sulphide type.

Claims

1. A substrate comprising:

a fibrous material; and

a photocatalytic coating material coating at least a portion of the fibrous material and including a photocatalytic semi-conducting material and an adhesion promoter for promoting adhesion of the photocatalytic semi-conducting material to the fibrous material,

wherein the photocatalytic semi-conducting material comprises titanium oxide which is at least partly crystallized in anatase form and the photocatalytic coating material coats fibers in the portion of the fibrous material over a thickness of between 30 and 50 nm, which is comparable to a means size of particles of the at least partly crystallized titanium oxide in anatase form.

2. The substrate according to claim 1, wherein

the titanium oxide is in a form of one of particles in colloidal suspension and a powder.

3. The substrate according to claim 1, wherein the photocatalytic semi-conducting material comprises a titanium oxide from one of thermal decomposition of organometallic and at least one metal halide precursor in the photocatalytic coating material.

4. The substrate according to claim 1, wherein the adhesion promoter comprises at least one of an organic material and an organic/inorganic hybrid material.

5. The substrate according to claim 1, wherein the adhesion promoter comprises a silicon-comprising component selected from the group consisting of silane, silicone and siloxane.

6. The substrate according to claim 1, wherein the adhesion promoter comprises at least one organic polymer selected from the group consisting of acrylic polymers and fluorinated polymers.

7. The substrate according to claim 1, wherein the adhesion promoter comprises at least one oxide selected from the group consisting of TiO₂ and SiO₂ from one of thermal decomposition of silicon-comprising, organometallic or metal halide precursor(s) within the photocatalytic coating material.

8. The substrate according to claim 1, wherein the adhesion promoter comprises at least one inorganic component selected from the group consisting of aluminium phosphates, potassium aluminosilicates and calcium aluminosilicates.

9. The substrate according to claim 1, wherein the adhesion promoter forms part of a binder providing cohesion of the fibrous material.

10. The substrate according to claim 1, wherein the fibrous material comprises at least one of insulation mineral wool and reinforcing glass strands.

11. The substrate according to claim 1, wherein the fibrous material is one of web, felt, mould, paper and bulk material forms.

12. The substrate according to claim 1, wherein the fibrous material comprises one of a thermal insulation material, a sound insulation material, a liquid filter, a gas filter, a purifier, and a diffuser.

13. The substrate according to claim 1, wherein the adhesive promoter further comprises at least one additive selected from the group consisting of an antioxidant, an ultraviolet absorber and a hindered amine light stabilizer.

14. The substrate according to claim 1, wherein the adhesion promoter comprises at least one of an inorganic material and an organic/inorganic hybrid material.

15. A process for manufacturing a substrate, comprising:

depositing a liquid binder to bind fibers and forms a fibrous material; and

depositing a photocatalytic coating material in liquid phase over at least a portion of the fibrous material such that the photocatalytic coating material coats fibers in the portion of the fibrous material over a thickness of between 30 and 50 nm, which is comparable to a means size of particles of at least partly crystallized titanium oxide in anatase form, the photocatalytic material including a photocatalytic semi-conducting material and an adhesion promoter for promoting adhesion of the photocatalytic semi-conducting material to the firbous material,

wherein the photocatalytic semi-conducting material comprises titanium oxide at least partially crystallized in anatase form.

16. The process according to claim 15, wherein the depositing the photocatalytic coating material after converting the fibrous material into a finished product and before subjecting the finished product to a heat treatment.

17. The process according to claim 15, wherein the depositing the photocatalytic coating material comprises one of spraying, coating and dip coating.

18. The process according to claim 15, wherein the depositing the photocatalytic coating material comprises depositing the photocatalytic coating material downstream of a fiberizing device before heat treatment/conditioning devices.

19. The process according to claim 15, wherein the depositing the photocatalytic coating material comprises depositing the photocatalytic material while the fibrous material is being formed into mats.