Modification of surface wetting properties of a substrate

Patent metadata

Field	Value
Publication number	US-9427908-B2
Application number	US-44741607-A
Country	US
Kind code	B2
Filing date	Oct 10, 2007
Priority date	Oct 25, 2006
Publication date	Aug 30, 2016
Grant date	Aug 30, 2016

Abstract

A method of modifying the wetting properties of the surface of a substrate, the method comprising the step of applying a first mold having an imprint forming surface to said substrate to form a first imprint thereon, said imprint forming surface being chosen to modify the wetting properties of the substrate surface.

First claim

The invention claimed is:

1. A method of modifying the anisotropic wetting properties of the surface of a polymer substrate, the method comprising the steps of:
(A) applying a first mold having an imprint forming surface including patterns to said polymer substrate at a first temperature to form a first imprint on said polymer substrate;
(B) applying a second mold having an imprint forming surface including patterns having a smaller dimension than the patterns of said first mold to said first imprint at a second temperature that is different to said first temperature to form a second imprint that is in the same polymer substrate as the first imprint, said second mold configured to vary the size of said first imprint along the height of said first imprint when forming a second imprint on said first imprint which comprises a hierarchical structure; and
(C) orienting, during said applying step (B), said second mold relative to said first imprint to form said hierarchical structure on said polymer substrate for modifying the wetting properties of the polymer substrate surface.

2. A method according to claim 1 , comprising the step of selecting the shapes of said first and second imprints generally longitudinal such that each of said imprints extends about a longitudinal axis.

3. A method according to claim 2 , comprising the step of, during said orienting step, applying said second mold to said first imprint such that the longitudinal axes of the formed second imprint are disposed at an angle, relative to the longitudinal axes of the formed first imprint, in the range selected from the group consisting of 0° to 90°, 0° to 45° and 45° to 90°.

4. A method according to claim 3 , comprising the step of applying said longitudinal axis of said second mold generally parallel relative to the longitudinal axis of said first imprint.

5. A method according to claim 2 , comprising the step of applying said longitudinal axis of said second mold generally perpendicular relative to the longitudinal axis of said first imprint.

6. A method according to claim 1 , comprising the step of selecting the width of said first and second imprints in either the microscale or the nanoscale.

7. A method according to claim 1 , comprising the step of selecting the width dimension of the patterns of the second imprint forming surface to be smaller than the patterns of the first imprint forming surface.

8. A method according to claim 1 , comprising the step of selecting said polymer substrate as a thermoplastic polymer.

9. A method according to claim 1 , comprising the step of selecting said polymer substrate as one that comprises an epoxy based negative resist.

10. A method according to claim 1 , comprising the step of forming three-dimensional structures during at least one of said first and second applying steps.

11. A method according to claim 10 , comprising the step of selecting said three-dimensional structures from at least one of microstructures, nanostructures and combinations thereof.

12. A method according to claim 1 , comprising, before at least one of step (A) and step (B), the step of treating at least one of said first and second molds with an anti-stiction agent.

13. A method according to claim 1 , comprising the step of forming a defined pattern on the polymer substrate surface which either promotes fluid flow thereon or inhibits fluid flow thereon.

14. A method according to claim 1 , comprising, during step (A), the step of selecting a temperature that is above the glass transition temperature (Tg) of said polymer substrate.

15. A method according to claim 1 comprising, during step (B), the step of selecting a temperature that is below the glass transition temperature (Tg) of said polymer substrate.

16. A method according to claim 1 , comprising after step (C), forming one or more further imprints on said second imprint in a manner such that said one or more further imprints are at a different orientation to at least said second imprint, wherein the one or more further imprints on said second imprint are in the same polymer substrate as the second imprint.

Assignees

• Low Hong Yee
• Zhang Fengxiang
• Agency Science Tech & Res

Inventors

• Low Hong Yee
• Zhang Fengxiang

Classifications

• B29C59/02

  by mechanical means, e.g. pressing {(B29C59/007 takes precedence; embossing expanded porous articles B29C44/5627)} · CPC title

• B29C59/022 Primary

  characterised by the disposition or the configuration, e.g. dimensions, of the embossments or the shaping tools therefor · CPC title

• B29C2059/023

  Microembossing · CPC title

• B05D7/04

  to surfaces of films or sheets (producing layered products by applying coatings of pasty or pulverulent plastics B29C41/00) · CPC title

• B05D3/12

  by mechanical means · CPC title