Claims
- 1. A method of forming an anisotropically-conductive film or coated substrate, the steps of which comprise:
- (a) applying to the coated substrate, a layer of a liquid composition comprising:
- (i) a solidifiable ferrofluid composition, the ferrofluid comprising a colloidal suspension of ferromagnetic particles in a non-magnetic carrier liquid, and
- (ii) a plurality of electrically-conductive particles, dispersed in the ferrofluid,
- (b) exposing the liquid composition to a magnetic field to array the electrically-conductive particles in a non-random pattern, and
- (c) concurrent with or subsequent to step (b), exposing the liquid composition to conditions sufficient to solidify the liquid composition to form an anisotropically-conductive film, and
- (d) optionally, removing the layer of the formed solidified composition from the substrate.
- 2. A method according to claim 1 wherein the composition is curable and comprises at least a primary cure system, and solidification of the composition is achieved by effecting a primary cure.
- 3. A method according to claim 2 wherein the composition contains a latent cure system in addition to the primary cure system which is activatable to further cure said film or said coated substrate, respectively, at a time subsequent to solidification of the composition.
- 4. A method according to claim 1 which includes applying pressure to the layer of the composition prior to and/or during curing or other solidification of the composition.
- 5. A method according to claim 1 wherein the composition is applied to the substrate, and is then exposed to the magnetic field.
- 6. A method according to claim 1 wherein the composition is exposed to the magnetic field while the composition is being applied to the substrate.
- 7. A method according to claim 6 wherein the composition is applied to the substrate by stenciling or screen printing using stenciling or screen printing equipment having one or more magnets mounted appropriately on it.
- 8. A method according to claim 1 wherein the coating is applied to an active or passive electronic component, as the substrate.
- 9. A method according to claim 1 wherein the thickness of the layer of composition exposed to the magnetic field is not more than twice the average diameter of the electrically-conductive particles.
- 10. A method according to claim 1 wherein the composition is heated during exposure to the magnetic field.
Priority Claims (1)
Number |
Date |
Country |
Kind |
950589 |
Aug 1995 |
IEX |
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Parent Case Info
This is a divisional application of prior U.S. application Ser. No. 08/686,987, filed Jul. 25, 1996, now U.S. Pat. No. 5,851,644.
US Referenced Citations (62)
Foreign Referenced Citations (1)
Number |
Date |
Country |
0208391 |
Jan 1987 |
EPX |
Divisions (1)
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Number |
Date |
Country |
Parent |
686987 |
Jul 1996 |
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