POROUS BODY AND PROCESS FOR MANUFACTURING SAME

• US 20150075406A1
• Filed: 02/15/2012
• Published: 03/19/2015
• Est. Priority Date: 02/15/2012
• Status: Abandoned Application

• Current Assignee: Hokuetsu Corporation, University of Tokyo
• Original Assignee: Hokuetsu Kishu Paper Company Limited, University of Tokyo
• Inventors: Nemoto, Junji, Soyama, Toshihiko, Saito, Tsuguyuki, Isogai, Akira
• Application Number:
  US14/377,902
• Publication Number:
  US 20150075406A1
• Time in Patent Office: Days
• US Class Current: 106/164.01
• CPC Class Codes: B01D 2239/025 comprising nanofibres apparatus incorporating such gas filtering material see B01D46/546
• CPC Class Codes: B01D 2239/0654 Support layers
• CPC Class Codes: B01D 2239/1233 Fibre diameter
• CPC Class Codes: B01D 39/18 the material being cellulose or derivatives thereof cork or peat B01D39/1646 ; making filter paper D21F11/14
• CPC Class Codes: B01D 67/0002 Organic membrane manufacture
• CPC Class Codes: B01D 67/00042 by deposition of fibres, nanofibres or nanofibrils
• CPC Class Codes: B01D 67/00793 Dispersing a component, e.g. as particles or powder, in another component
• CPC Class Codes: B01D 67/0095 Drying
• CPC Class Codes: B01D 69/12 Composite membranes; Ultra-thin membranes
• CPC Class Codes: B01D 71/022 Metals
• CPC Class Codes: B01D 71/04 Glass
• CPC Class Codes: B01D 71/10 Cellulose; Modified cellulose
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: C08J 2301/00 Characterised by the use of cellulose, modified cellulose or cellulose derivatives
• CPC Class Codes: C08J 2369/00 Characterised by the use of polycarbonates; Derivatives of polycarbonates
• CPC Class Codes: C08J 9/0085 Use of fibrous compounding ingredients C08J9/0076 takes precedence
• CPC Class Codes: C08J 9/42 with macromolecular compounds
• CPC Class Codes: D06M 15/05 Cellulose or derivatives thereof

Abstract

The object of the present invention is to provide a porous body having fluid permeance, which contains cellulose-based nanofibers having an extremely thin fiber diameter and high hydrophilicity, and to manufacture a porous body at low cost. The porous body according to the present invention is a porous body in which nanofibers are entangled to form net-like structural bodies in pores of a porous support having many pores that are connecting with one another, wherein the nanofibers are cellulose-based nanofibers, and have a number average fiber diameter of from 1 to 100 nm.

Claims

1. A porous body in which nanofibers are entangled to form net-like structural bodies in pores of a porous support having many pores that are connecting with one another,

wherein the nanofibers are cellulose-based nanofibers, and have a number average fiber diameter of from 1 to 100 nm.

2. The porous body according to claim 1, wherein the net-like structural bodies have a number average pore diameter of from 10 to 200 nm.

3. The porous body according to claim 1, wherein the support has an average fine pore diameter of from 0.01 to 20 μ

m.

4. The porous body according to claim 1, wherein the support is either one of a porous film or a fiber sheet.

5. The porous body according to claim 1,

wherein the net-like structural bodies contain a surfactant, and

the content of the surfactant is from 0.10 to 100% by mass in terms of solid content concentration with respect to the dry mass of the nanofibers.

6. The porous body according to claim 5, wherein the surfactant is a cationic surfactant.

11. The porous body according to claim 3, wherein the support is either one of a porous film or a fiber sheet.

12. The porous body according to claim 2,

wherein the net-like structural bodies contain a surfactant, and

the content of the surfactant is from 0.10 to 100% by mass in terms of solid content concentration with respect to the dry mass of the nanofibers.

13. The porous body according to claim 12, wherein the surfactant is a cationic surfactant.

14. The porous body according to claim 1, wherein the net-like structural bodies contain a surfactant, and the surfactant is a cationic surfactant.

20. The porous body according to claim 1, wherein the raw material of the cellulose-based nanofibers contains at least any one of kraft pulps derived from various wood materials, sulfite pulp, waste paper pulps, mechanical pulps and non-wood pulp.

22. The porous body according to claim 1, wherein the support is inorganic fiber sheets, animal fiber sheets, metal fiber sheets, porous films, porous ceramics, recycled fiber sheets, vinylon sheets or polyvinylidene chloride sheets.

7. A process for manufacturing a porous body, including:

a step of preparing a dispersion liquid, in which a dispersion liquid that cellulose-based nanofibers having a number average fiber diameter of from 1 to 100 nm are dispersed in a dispersion medium is prepared,

a step of attaching, in which the dispersion liquid is attached to a porous support having many pores that are connecting with one another, and

a step of drying, in which the support is dried to remove the dispersion medium.

8. The process for manufacturing a porous body according to claim 7, wherein the dispersion medium is water.

9. The process for manufacturing a porous body according to claim 7, wherein the dispersion liquid contains the nanofibers by from 0.001 to 0.500% by mass in terms of solid content concentration with respect to the total mass of the dispersion liquid.

10. The process for manufacturing a porous body according to claim 7, wherein the dispersion liquid further contains a surfactant, and contains the surfactant by from 0.0001 to 1.0000% by mass in terms of solid content concentration with respect to the total mass of the dispersion liquid.

15. The process for manufacturing a porous body according to claim 7, wherein the dispersion liquid contains a surfactant, and the surfactant is a cationic surfactant.

16. The process for manufacturing a porous body according to claim 10, wherein the surfactant is a cationic surfactant.

17. The process for manufacturing a porous body according to claim 9, wherein the dispersion liquid further contains a surfactant, and contains the surfactant by from 0.0001 to 1.0000% by mass in terms of solid content concentration with respect to the total mass of the dispersion liquid.

18. The process for manufacturing a porous body according to claim 17, wherein the surfactant is a cationic surfactant.

19. The process for manufacturing a porous body according to claim 7, further including a step of removing, in which the excessively attached dispersion liquid was removed, and the step of removing is performed after the step of attaching and before the step of drying.

21. The process for manufacturing a porous body according to claim 7, wherein the raw material of the cellulose-based nanofibers contains at least any one of kraft pulps derived from various wood materials, sulfite pulp, waste paper pulps, mechanical pulps and non-wood pulp.

23. The process for manufacturing a porous body according to claim 7, wherein the support is inorganic fiber sheets, animal fiber sheets, metal fiber sheets, porous films, porous ceramics, recycled fiber sheets, vinylon sheets or polyvinylidene chloride sheets.