Multi-functional material with photocalytic functions and method of manufacturing same

• US 5,853,866 A
• Filed: 10/06/1995
• Issued: 12/29/1998
• Est. Priority Date: 12/10/1993
• Status: Expired due to Term

• Current Assignee: Toto Limited
• Original Assignee: Toto Limited
• Inventors: Hayakawa, Makoto, Watanabe, Toshiya, Kitamura, Atsushi, Kojima, Eiichi, Machida, Mitsuyoshi, Nakashima, Yasushi, Kuga, Tatsuhiko, Chikuni, Makoto, Norimoto, Keiichiro, Kimura, Tamon, Saeki, Yoshimitsu
• Primary Examiner(s): Bell, James J.
• Assistant Examiner(s): COPENHEAVER, BLAINE R
• Application Number:
  US08/501,110
• Time in Patent Office: 1,180 Days
• Field of Search: 427/126.3, 427/214, 427/216, 427/217, 427/219, 428/309.9, 428/312.8, 428/313.9, 428/317.7, 430/947, 502/236, 502/242, 502/309, 502/439, 156/308.2, 156/309.6, 156/311
• US Class Current: 428/312.8
• CPC Class Codes: B01J 21/063 Titanium; Oxides or hydroxides thereof
• CPC Class Codes: B01J 35/30 characterised by their physical properties
• CPC Class Codes: B01J 35/39 Photocatalytic properties
• CPC Class Codes: B01J 37/0215 Coating
• CPC Class Codes: C03C 17/007 containing a dispersed phase, e.g. particles, fibres or flakes, in a continuous phase
• CPC Class Codes: C03C 17/3411 with at least two coatings of inorganic materials C03C17/36, C03C17/42 take precedence
• CPC Class Codes: C03C 2217/42 consisting of particles only
• CPC Class Codes: C03C 2217/425 consisting of a porous layer
• CPC Class Codes: C03C 2217/475 Inorganic materials
• CPC Class Codes: C03C 2217/477 Titanium oxide
• CPC Class Codes: C03C 2217/71 Photocatalytic coatings
• CPC Class Codes: C04B 33/00 Clay-wares monolithic refractories or refractory mortars C04B35/66; porous products C04B38/00
• CPC Class Codes: C04B 35/10 based on aluminium oxide
• CPC Class Codes: C04B 41/0045 Irradiation; Radiation, e.g. with UV or IR C04B41/0036 takes precedence
• 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 41/4537 by the sol-gel process
• CPC Class Codes: C04B 41/4539 as a emulsion, dispersion or suspension
• CPC Class Codes: C04B 41/455 the coating or impregnating process including a chemical conversion or reaction
• CPC Class Codes: C04B 41/4554 the coating or impregnating material being an organic or organo-metallic precursor of an inorganic material
• CPC Class Codes: C04B 41/4562 : Photographic methods, e.g. making use of photo-sensitive materials
• CPC Class Codes: C04B 41/5022 : with vitreous materials composition of vitreous glazes and enamels C03C; ceramic pigments C09C1/0009
• CPC Class Codes: C04B 41/5041 : Titanium oxide or titanates
• CPC Class Codes: C04B 41/505 : Tin oxide
• CPC Class Codes: C04B 41/51 : Metallising , e.g. infiltration of sintered ceramic preforms with molten metal covering materials with metals in general C23C; ceramic compositions containing free metal bonded to carbides, diamond, oxides, borides, nitrides, silicides, e.g. cermets, or other metal compounds, e.g. oxynitrides or sulfides, other than as macroscopic reinforcing agents C22C; infiltration of preforms containing free metal, e.g. cermets C22C
• CPC Class Codes: C04B 41/5111 : Ag, Au, Pd, Pt or Cu
• 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: C04B 41/81 : Coating or impregnation
• CPC Class Codes: C04B 41/89 : for obtaining at least two superposed coatings having different compositions
• CPC Class Codes: Y10S 430/148 : Light sensitive titanium compound containing
• CPC Class Codes: Y10T 428/24909 : Free metal or mineral containing
• CPC Class Codes: Y10T 428/24997 : Of metal-containing material
• CPC Class Codes: Y10T 428/249974 : Metal- or silicon-containing element
• CPC Class Codes: Y10T 428/249982 : With component specified as adhesive or bonding agent
• CPC Class Codes: Y10T 428/249985 : Composition of adhesive or bonding component specified

Abstract

Multi-functional materials are classified into those which have a photocatalytic layer 2 with a photocatalytic function directly disposed on the surface of a base 1 and those which have a photocatalytic layer 2 with a photocatalytic function disposed on the surface of a base 1 through a binder layer 6 interposed therebetween. Photocatalytic particles of the photocatalytic layer 2 are joined together by a surface energy or solid-state sintering. The photocatalytic layer 2 may have a structure in which fine particles fill interstices defined between photocatalytic particles or a structure in which no fine particles fill interstices defined between photocatalytic particles. A metal such as Ag, Pt, or the like may be fixed or not fixed to surfaces of the photocatalytic particles.

Claims

1. A multi-functional material exhibiting a photocatalytic function, comprising:

a base and a photocatalytic layer having a photocatalytic function and disposed on a surface of said base;

said photocatalytic layer including at least a surface layer exposed outwardly;

said surface layer comprising fine photocatalytic particles intimately joined together in abutting relationship such that pores are defined therebetween at a predetermined porosity;

said photocatalytic layer being disposed on the surface of said base through a binder layer interposed therebetween;

said photocatalytic layer including a surface layer exposed outwardly and a lower layer embedded in said binder layer;

said multi-functional material being a multi-functional glass;

said base being made of soda glass; and

said binder layer containing a smaller quantity of alkali-metal component than said base.

2. A multi-functional material exhibiting a photocatalytic function, comprising:

a base and a photocatalytic layer having a photocatalytic function and disposed on a surface of said base;

said photocatalytic layer including at least a surface layer exposed outwardly;

said surface layer comprising fine photocatalytic particles intimately joined together in abutting relationship such that pores are defined therebetween at a predetermined porosity;

said photocatalytic layer being disposed on the surface of said base through a binder layer interposed therebetween;

said photocatalytic layer including a surface layer exposed outwardly and a lower layer embedded in said binder layer;

said multi-functional material being a multi-functional glass;

said base being made of soda glass; and

said binder layer being made of silica.

3. A multi-functional material according to claim 2, wherein said material is heat-treated in a range of 300°

-500°

C. to embed the portion of the lower layer of the photocatalytic layer in the binder layer.

4. A multi-functional material exhibiting a photocatalytic function, comprising:

a base and a photocatalytic layer having a photocatalytic function and disposed on a surface of said base;

said photocatalytic layer including at least a surface layer exposed outwardly;

said surface layer comprising fine photocatalytic particles intimately joined together in abutting relationship such that pores are defined therebetween at a predetermined porosity;

said photocatalytic layer being disposed on the surface of said base through a binder layer interposed therebetween;

said photocatalytic layer including a surface layer exposed outwardly and a lower layer embedded in said binder layer;

said multi-functional material being a multi-functional glass;

said multi-functional material being a multi-functional glass; and

said photocatalytic layer being produced by hydrolyzing titanium alkoxide to obtain titanium hydroxide, dehydrolyzing and condensing the titanium hydroxide, and further crystallizing the titanium hydroxide.

5. A method of manufacturing a multi-functional material exhibiting a photocatalytic function, comprising the steps of:

forming a photocatalytic layer of photocatalytic particles on a substantially planar binder layer of thermoplastic material;

placing or applying said substantially planar binder layer to a surface of a base;

thereafter softening said binder layer to embed a portion of a lower layer of the photocatalytic layer in the binder layer; and

solidifying said binder layer;

said binder layer having a softening temperature lower than a softening temperature of said base, and said step of softening the binder layer involves heating the binder layer at an atmospheric temperature which is higher than the softening temperature of said binder layer by X, where 20°

<

X<

320°

C., and lower than the softening temperature of said base.

6. A method according to claim 5, wherein X satisfies the equation 40°

C.≦

X≦

300°

C.

7. A method according to claim 5, wherein the step of softening the binder layer involves hot pressing of the photocatalytic layer and the binder layer to embed the portion of the lower layer of the photocatalytic layer in the binder layer.

8. A method of manufacturing a multi-functional material exhibiting a photocatalytic function, comprising the steps of:

dispersing a sol, a precursor, or a suspension of photocatalytic particles in a solution with a dispersant to form a dispersion, forming a photocatalytic layer of the photocatalytic particles using the dispersion on a substantially planar binder layer of thermoplastic material;

placing or applying said substantially planar binder layer to a surface of a base;

thereafter softening the binder layer to embed a portion of a lower layer of the photocatalytic layer in the binder layer; and

solidifying the binder layer;

said dispersant consisting of a component which is vaporized at a temperature lower than a heat-treatment temperature at which said binder layer is softened.

9. A method of manufacturing a multi-functional material exhibiting a photocatalytic function, comprising the steps of:

forming a photocatalytic layer of photocatalytic particles on a substantially planar binder layer of thermoplastic material;

placing or applying said substantially planar binder layer to a surface of a base;

thereafter softening said binder layer to embed a portion of a lower layer of the photocatalytic layer in the binder layer, and solidifying said binder layer;

said photocatalytic particles and said binder layer having respective specific gravities δ

t, δ

b which satisfy the relationship;

0≦

δ

t-δ

b≦

3.0.

10. A method according to claim 9, wherein said photocatalytic layer is disposed on the surface of said base through first and second binder layers interposed therebetween, said first binder layer being disposed on said base and said second binder layer being disposed on said first binder layer, and said photocatalytic particles and said second binder layer have said respective specific gravities δ

t, δ

b which satisfy the relationship;

0≦

δ

t-δ

b≦

3.0.