FLUORORESIN FILM MATERIAL AND PRODUCTION PROCESS THEREFOR

• US 20190308142A1
• Filed: 07/20/2017
• Published: 10/10/2019
• Est. Priority Date: 08/26/2016
• Status: Active Application

• Current Assignee: Taiyo Kogyo Corporation
• Original Assignee: Taiyo Kogyo Corporation
• Inventors: Abe, Kazuhiro
• Application Number:
  US16/327,619
• Publication Number:
  US 20190308142A1
• Time in Patent Office: Days
• CPC Class Codes: B01D 2325/10 Catalysts being present on the surface of the membrane or in the pores
• CPC Class Codes: B01D 53/86 Catalytic processes
• CPC Class Codes: B01D 71/36 Polytetrafluoroethene
• CPC Class Codes: B01J 21/063 Titanium; Oxides or hydroxides thereof
• CPC Class Codes: B01J 27/232 Carbonates
• CPC Class Codes: B01J 31/38 of titanium, zirconium or hafnium
• CPC Class Codes: B01J 35/00 Catalysts, in general, characterised by their form or physical properties
• CPC Class Codes: B01J 35/30 characterised by their physical properties
• CPC Class Codes: B01J 35/39 Photocatalytic properties
• CPC Class Codes: B01J 37/02 Impregnation, coating or precipitation B01J37/0009 and B01J37/0018 take precedence ; protection by coating B01J33/00
• CPC Class Codes: B01J 37/08 Heat treatment B01J37/0009, B01J37/0018 take precedence
• CPC Class Codes: B32B 27/18 characterised by the use of special additives
• CPC Class Codes: B32B 27/20 using fillers, pigments, thixotroping agents
• CPC Class Codes: B32B 27/30 comprising vinyl (co)polymers; comprising acrylic (co)polymers
• CPC Class Codes: C08J 7/043 Improving the adhesiveness of the coatings per se, e.g. forming primers adhesives in the form of films or foils characterised by the primer layers between the polymer carriers and the adhesives C09J7/50
• CPC Class Codes: C08K 2003/2241 Titanium dioxide
• CPC Class Codes: C08K 3/013 Fillers, pigments or reinforcing additives
• CPC Class Codes: C08K 3/22 of metals
• CPC Class Codes: C08L 2205/025 containing two or more polymers of the same hierarchy C08L, and differing only in parameters such as density, comonomer content, molecular weight, structure
• CPC Class Codes: C08L 27/18 Homopolymers or copolymers or tetrafluoroethene
• CPC Class Codes: C09D 127/18 : Homopolymers or copolymers of tetrafluoroethene
• CPC Class Codes: Y02C 20/30 : of perfluorocarbons [PFC], hydrofluorocarbons [HFC] or sulfur hexafluoride [SF6]

Abstract

The following phenomenon occurring in a fluororesin membrane material using, as its main material, a PTFE having a photocatalyst layer on a surface thereof is prevented: the surface of the membrane material is contaminated after the lapse of some years from the start of its use. A photocatalyst layer arranged on the PTFE layer of a Type A membrane material is formed of a photocatalyst and fluororesins, and the fluororesins are formed of at least one of a FEP ora PFA, and a PTFE. Here, the amount of the PTFE is preferably larger than that of at least one of the FEP or the PFA, and the weight of the photocatalyst is preferably 40% or less with respect to the total weight of the photocatalyst and the fluororesins.

Claims

1. A fluororesin membrane material, comprising:

a fluororesin layer containing a polytetrafluoroethylene (PTFE) as a fluororesin; and

a photocatalyst layer arranged on at least one outermost surface of the fluororesin layer, the photocatalyst layer containing a photocatalyst and fluororesins,

wherein the photocatalyst and the fluororesins in the photocatalyst layer satisfy a photocatalyst ratio, which is a ratio of a weight of the photocatalyst to a total weight of the photocatalyst and the fluororesins, of 40% or less, and

wherein the fluororesins in the photocatalyst layer are formed of a specific fluororesin that is a fluorinated resin copolymer having a melting point of 240°

C. or more and a continuous use temperature of 200°

C. or more, and the PTFE, and the specific fluororesin and the PTFE in the photocatalyst layer satisfy a specific fluororesin ratio, which is a ratio of a weight of the specific fluororesin to a total weight of the specific fluororesin and the PTFE, of 50% or less.

2. The fluororesin membrane material according to claim 1, wherein the photocatalyst ratio is 25% or less.

3. The fluororesin membrane material according to claim 1, wherein the photocatalyst ratio is 20% or less.

4. The fluororesin membrane material according to claim 1, wherein the photocatalyst ratio is 15% or more.

5. The fluororesin membrane material according to claim 1, wherein the specific fluororesin ratio is 30% or less.

6. The fluororesin membrane material according to claim 1, wherein the specific fluororesin ratio is 25% or less.

7. The fluororesin membrane material according to any onc of claim 1, wherein the specific fluororesin ratio is 20% or less.

8. The fluororesin membrane material according to any onc of claim 1, wherein the specific fluororesin ratio is 10% or more.

9. The fluororesin membrane material according to claim 1, wherein the specific fluororesin is at least one of a FEP or a PFA.

10. The fluororesin membrane material according to claim 1, wherein the photocatalyst layer contains a carbonate.

11. The fluororesin membrane material according to claim 10, wherein a weight of the carbonate in the photocatalyst layer is 20 wt % or less with respect to the weight of the photocatalyst in the photocatalyst layer.

12. The fluororesin membrane material according to claim 10, wherein a weight of the carbonate in the photocatalyst layer is 10 wt % or less with respect to the weight of the photocatalyst in the photocatalyst layer.

13. The fluororesin membrane material according to claim 10, wherein a weight of the carbonate in the photocatalyst layer is 5 wt % or more with respect to the weight of the photocatalyst in the photocatalyst layer.

14. The fluororesin membrane material according to claim 10, wherein the photocatalyst layer contains an inorganic pigment for coloring the photocatalyst layer.

15. The fluororesin membrane material according to claim 10, wherein a total weight of the photocatalyst and the carbonate in the photocatalyst layer is 40% or less with respect to a total weight of the photocatalyst, the carbonate, and the fluororesins in the photocatalyst layer.

16. The fluororesin membrane material according to claim 14, wherein a total weight of the photocatalyst, the carbonate, and the inorganic pigment in the photocatalyst layer is 40% or less with respect to a total weight of the photocatalyst, the carbonate, the inorganic pigment, and the fluororesins in the photocatalyst layer.

17. A method of producing a fluororesin membrane material for obtaining a fluororesin membrane material by forming a photocatalyst layer containing a photocatalyst and fluororesins on at least one outermost surface of a fluororesin layer containing a polytetrafluoroethylene (PTFE) as a fluororesin, the method comprising:

applying a dispersion containing the photocatalyst and the fluororesins to at least one outermost surface of the fluororesin layer;

drying the dispersion;

calcining the fluororesin layer having applied thereto the dispersion at a temperature equal to or more than a melting point of any fluororesin of the fluororesins incorporated into the dispersion; and

cooling the calcined fluororesin layer having applied thereto the dispersion to room temperature,

wherein the photocatalyst and the fluororesins in the dispersion to be applied to the fluororesin layer satisfy a photocatalyst ratio, which is a ratio of a weight of the photocatalyst to a total weight of the photocatalyst and the fluororesins, of 40% or less, and

wherein the fluororesins in the dispersion to be applied to the fluororesin layer are formed of a specific fluororesin that is a fluorinated resin copolymer having a melting point of 240°

C. or more and a continuous use temperature of 200°

C. or more, and the PTFE, and the specific fluororesin and the PTFE in the dispersion satisfy a specific fluororesin ratio, which is a ratio of a weight of the specific fluororesin to a total weight of the specific fluororesin and the PTFE, of 50% or less.