Filter

• US 8,758,542 B2
• Filed: 11/09/2009
• Issued: 06/24/2014
• Est. Priority Date: 03/25/2009
• Status: Expired due to Fees

• Current Assignee: Nanyang Technology University
• Original Assignee: Nanyang Technology University
• Inventors: Gong, Haiqing, Chen, Longqing
• Primary Examiner(s): BELL, WILLIAM P
• Application Number:
  US13/260,235
• Publication Number:
  US 20120024775A1
• Time in Patent Office: 1,688 Days
• Field of Search: 156/152, 264/317, 264/413, 264/425, 264/496
• US Class Current: 156/245
• CPC Class Codes: B01D 2323/345 UV-treatment
• CPC Class Codes: B01D 2325/02 Details relating to pores or porosity of the membranes
• CPC Class Codes: B01D 2325/021 Pore shapes
• CPC Class Codes: B01D 2325/02834 more than 0.1 and up to 1 µm
• CPC Class Codes: B01D 67/0032 by elimination of segments of the precursor, e.g. nucleation-track membranes, lithography or laser methods
• CPC Class Codes: B01D 67/0034 by micromachining techniques, e.g. using masking and etching steps, photolithography
• CPC Class Codes: B01D 69/06 Flat membranes
• CPC Class Codes: B01D 69/10 Supported membranes; Membrane supports

Abstract

The present invention relates to a membrane filter comprising a plurality of pores of substantially the same size. The membrane filter may be supported by at least one support (e.g. in the form of a support grid) and is able to handle a large flux and pressure in use. The invention also relates to a method of fabrication of such a filter membrane using a solvable mold.

Claims

1. A method for preparing a filter device, comprising:

(i) providing a solvable mold comprising an array of pillars of substantially the same size;

(ii) depositing a curable resin layer on the solvable mold, curing the resin to form a membrane filter comprising an array of pores of substantially the same size in contact with the solvable mold;

(iii) contacting at least a portion of a first surface of the membrane filter away from the mold to a first support; and

(iv) dissolving away the solvable mold leaving the membrane filter in contact with the support;

wherein the curable resin of step (ii) comprises a uv curable resin or a temperature curable resin and step (ii) comprises;

(a) depositing the uv curable resin or temperature curable resin onto the solvable mold;

(b) positioning a plate with a substantially flat surface over the uv curable resin or temperature curable resin and exerting pressure on the resin;

(c) exposing the resin to UV light or a temperature suitable to cure the resin as appropriate; and

(d) removing the plate and any excess resin to obtain a membrane filter with a substantially flat exposed first surface.

2. The method according to claim 1, further comprising bonding the first support to at least a portion of the first surface of the membrane filter.

3. The method according to claim 1, further comprising bonding at least a portion of a second surface of the membrane filter to a second support.

4. The method according to claim 3, wherein the portion(s) of the membrane in contact with the support(s) comprises a circumferential or peripheral portion(s) of the membrane.

5. The method according to claim 3 wherein the first and/or second support is substantially rigid and/or permeable to fluid or gas to or from the membrane filter.

6. The method according to claim 1, wherein step (i) comprises providing a through hole or blind hole mold wherein the holes are substantially the same size and using a solvable resin to cast the solvable mold from the through hole or blind hole mold.

7. The method according to claim 1, wherein the solvable mold is soluble in a solvent.

8. The method according to claim 7, wherein the solvent is water.