Sheet composed of exfoliated clay mineral and method for producing same

Patent metadata

Field	Value
Publication number	US-10563104-B2
Application number	US-201414909370-A
Country	US
Kind code	B2
Filing date	Jul 16, 2014
Priority date	Aug 1, 2013
Publication date	Feb 18, 2020
Grant date	Feb 18, 2020

Abstract

A sheet including exfoliated clay minerals, having a density of 1.6 g/cm 3 or less and a compression ratio of 20% or more.

First claim

The invention claimed is:

1. A sheet consisting of exfoliated clay minerals, having a density of 1.6 g/cm 3 or less, a thickness of 0.1 to 10 mm and a compression ratio of 20% or more, the exfoliated clay minerals being selected from the group consisting of mica, montmorillonite, iron montmorillonite, beidellite, saponite, hectorite, stevensite or nontronite.

2. The sheet according to claim 1 , having a helium gas permeability coefficient in the thickness direction of 3.7×10 −5 cm 2 s −1 cmHg −1 or more.

3. The sheet according to claim 1 , wherein the exfoliated clay minerals have a thickness of 0.5 nm to 1000 nm.

4. The sheet according to claim 1 , wherein the exfoliated clay minerals are a single layer or a laminate of two or more layers.

5. The sheet according to claim 1 , wherein a void ratio, defined as the ratio of the total sum of volumes of voids having an equivalent diameter of 15 μm or more and the total volume in a region of interest, is 3 vol % or less.

6. The sheet according to claim 1 , having a bending strength of 1 MPa or more.

7. A sealing material comprising the sheet according to claim 1 .

8. The sealing material according to claim 7 , that is a gasket or a packing.

9. A method for producing the sheet according to claim 1 , comprising forming exfoliated clay minerals into a sheet by assembling the exfoliated clay minerals without the exfoliated clay minerals being oriented.

10. The method for producing a sheet according to claim 9 , wherein a dispersion in which the exfoliated clay minerals are dispersed is freeze-dried, and then subjected to compression forming.

11. The method for producing a sheet according to claim 9 , wherein clay mineral are exfoliated to obtain the exfoliated clay minerals.

12. The method for producing a sheet according to claim 9 , wherein the bulk density of the exfoliated clay minerals is 0.4 g/cm 3 or less.

13. A sheet comprising 90 wt % or more of exfoliated clay minerals, having a density of 1.6 g/cm 3 or less, a thickness of 0.1 to 10 mm and a compression ratio of 20% or more, the exfoliated clay minerals being selected from the group consisting of mica, montmorillonite, iron montmorillonite, beidellite, saponite, hectorite, stevensite or nontronite, the exfoliated clay minerals having a thickness of 0.5 nm to 1000 nm.

14. The sheet according to claim 13 , having a helium gas permeability coefficient in the thickness direction of 3.7×10 −5 cm 2 s −1 cmHg −1 or more.

15. The sheet according to claim 13 , wherein a void ratio, defined as the ratio of the total sum of volumes of voids having an equivalent diameter of 15 μm or more and the total volume in a region of interest, is 3 vol % or less.

16. The sheet according to claim 13 , having a bending strength of 1 MPa or more.

17. A sealing material comprising the sheet according to claim 13 .

18. A sheet comprising 90 wt % or more of exfoliated clay minerals, having a density of 1.6 g/cm 3 or less, a thickness of 0.1 to 10 mm and a compression ratio of 20% or more, the exfoliated clay minerals being selected from the group consisting of mica, montmorillonite, iron montmorillonite, beidellite, saponite, hectorite, stevensite or nontronite, wherein a void ratio, defined as the ratio of the total sum of volumes of voids having an equivalent diameter of 15 μm or more and the total volume in a region of interest, is 3 vol % or less.

19. The sheet according to claim 18 , having a helium gas permeability coefficient in the thickness direction of 3.7×10 −5 cm 2 s −1 cmHg −1 or more.

20. The sheet according to claim 18 , having a bending strength of 1 MPa or more.

21. A sealing material comprising the sheet according to claim 18 .

22. A sheet comprising 90 wt % or more of exfoliated clay minerals, having a density of 1.6 g/cm 3 or less, a thickness of 0.1 to 10 mm, a compression ratio of 20% or more and a bending strength of 1 MPa or more, the exfoliated clay minerals being selected from the group consisting of mica, montmorillonite, iron montmorillonite, beidellite, saponite, hectorite, stevensite or nontronite.

23. The sheet according to claim 22 , having a helium gas permeability coefficient in the thickness direction of 3.7×10 −5 cm 2 s −1 cmHg −1 or more.

24. The sheet according to claim 22 , wherein a void ratio, defined as the ratio of the total sum of volumes of voids having an equivalent diameter of 15 μm or more and the total volume in a region of interest, is 3 vol % or less.

25. A sealing material comprising the sheet according to claim 22 .

Assignees

• Nichias Corp

Inventors

• Natori Hirotaka
• Watanabe Tomokazu
• Kitajima Nahoko

Classifications

• F16J15/102

  characterised by material · CPC title

• C09K3/1003 Primary

  Pure inorganic mixtures · CPC title

• C09K2003/1078

  Fire-resistant, heat-resistant materials · CPC title

• C09K2200/0252

  Clays · CPC title

• C09K2003/1084

  Laminates · CPC title