Anisotropic conductive compound
View Patent ↗An anisotropic conductive compound includes an electrically conducting material suspended in a binder. The electrically conducting material includes nickel coated particles having a coating of silver or gold over the nickel coat and/or gold or silver coated nickel particles. In one embodiment, the binder is formed from the reaction product of a catalyst and a compound comprising an aromatic epoxy resin, a dimer fatty acid diglycidyl ester and oxirane. In another embodiment, the binder is formed from the reaction product of a novalac resin, a catalyst and either a heat polymerized aromatic epoxy resin or a phenoxy modified epoxy novalac resin.
1. An anisotropic conductive material configured to be cured in the presence of a magnetic field, said anisotropic conductive material comprising electrically conducting material suspended in a binder, said electrically conducting material comprising a plurality of non-magnetic particles, each of which is coated with a layer of nickel and a layer of electrically conductive material, said electrically conducting material forming electrically conductive and isolated parallel paths when cured in the presence of a magnetic field.
2. The anisotropic conductive material as set forth in claim 1 , wherein each particle is formed from one of (i) carbon/graphite, (ii) glass and (iii) mica.
3. The anisotropic conductive material as set forth in claim 2 , wherein each glass particle is at least one of a solid and a hollow glass sphere.
4. The anisotropic conductive material as set forth in claim 1 , wherein each particle has a spherical shape.
5. The anisotropic conductive material as set forth in claim 1 , wherein an average maximum dimension of the particles including their coatings is between 10 μm and 25 μm.
6. The anisotropic conductive material as set forth in claim 1 , wherein the binder is formed from the reaction product of a catalyst and compound comprising an aromatic epoxy resin, a dimer fatty acid diglycidyl ester and an oxirane.
7. The anisotropic conductive material as set forth in claim 6 , wherein the oxirane is a (butoxy methyl)-butyl glycidyl ether.
8. The anisotropic conductive material as set forth in claim 6 , wherein the compound includes about one-third by weight of each of the aromatic epoxy resin, the dimer fatty acid diglycidyl ester and the oxirane.
9. The anisotropic conductive material as set forth in claim 6 , wherein the catalyst includes a quaternary cyanyl R-substituted amine.
10. The anisotropic conductive material as set forth in claim 6 , wherein the aromatic epoxy resin is formed from the reaction product of bisphenol-A and epichlorohydrin.
11. The anisotropic conductive material as set forth in claim 6 , further wherein the binder further includes a UV curable modifier.
12. The anisotropic conductive material as set forth in claim 11 , wherein the binder further includes a phenolic resin.
13. The anisotropic conductive material as set forth in claim 12 , wherein the phenolic resin is a novalac resin.
14. The anisotropic conductive material as set forth in claim 13 , wherein the novalac resin is formed from the reaction product of formaldehyde and one of phenol, cresol and bisphenol-A.
15. The anisotropic conductive material as set forth in claim 1 , wherein the binder is formed from the reaction product of a phenolic resin, a catalyst and one of (i) a thermally polymerized aromatic epoxy resin and (ii) a phenoxy modified epoxy novalac resin.
16. The anisotropic conductive material as set forth in claim 15 , wherein the phenolic resin is a novalac resin.
17. The anisotropic conductive material as set forth in claim 15 , wherein the phenolic resin and the novalac resin are formed from the reaction product of formaldehyde and one of phenol, cresol and bisphenol-A.
18. The anisotropic conductive material as set forth in claim 1 , wherein the electrically conductive material includes at least one of gold and silver.
19. The anisotropic conductive material as set forth in claim 1 , wherein the layer of electrically conductive material on each particle overlays the nickel layer on the particle.
20. The anisotropic conductive material as set forth in claim 1 , wherein the magnetic field is at least one of a DC magnetic field and an AC magnetic field.