Resin particle, conductive particle and anisotropic conductive adhesive containing the same
View Patent ↗Resin particles comprised of an acrylic resin. Not only is the maximum compression deformation ratio thereof as great as 60% or more but also the load required for 60% compression deformation is as small as 60 mN or less. Wiring boards are therefore coupled in using an anisotropic conductive adhesive obtained by first manufacturing conductive particles having a conductive coating formed on a resin particle surface of the resin particles by adhering a conductive material to the surface of the above resin particles as a core. On dispersing the conductive particles in an adhesive material, the conductive particles sandwiched between metallic wires of the wiring boards are greatly deformed by a small load, so that the electrical devices having a high conduction reliability can be obtained.
1. A resin particle comprising a polymer of monomers containing a urethane compound and an acrylic acid ester, having a maximum compression deformation ratio of 60% or more, and needing a load less than or equal to 60 mN for a compression deformation by 60%.
2. The resin particle accordingly to claim 1 , wherein the load necessary for the compression deformation by 60% is less than or equal to 30 mN.
3. The resin particle according to claim 1 , wherein the resin particle is formed by introducing a treatment liquid containing a monomer with pressure into a medium liquid via a porous membrane to form a droplet of the treatment liquid in the medium liquid and to harden the treatment liquid composing the droplet.
4. The resin particle according to claim 1 , wherein the urethane compound of 5 or more parts by weight is contained with respect to the monomer of 100 parts by weight.
5. The resin particle according to claim 1 , wherein the urethane compound of 25 or more parts by weight contained with respect to the monomer of 100 parts by weight.
6. The resin particle according to claim 1 , wherein the urethane compound includes a polyfunctional urethane acrylate.
7. The resin particle according to claim 1 , wherein the urethane compound includes a bifunctional urethane acrylate.
8. The resin particle according to claim 1 , wherein the acrylic resin includes a polymer of monomers containing either or both an acrylic acid ester having a linear chain structure and an acrylic acid ester having a branching structure.
9. A conductive particle comprising:
A resin particle as a core, having an acrylic resin as a main component, having a maximum compression deformation ratio of 60% or more, and needing a load of less than or equal to 60 mN for a compression deformation by 60%; and
a conductive material bonded to a surface of the resin particle.
10. The conductive particle according to claim 9 , wherein the conductive material is defined as a metallic material.
11. An anisotropic conductive adhesive comprising:
a conductive particle dispersed within an adhesive material;
a resin particle comprising a polymer of monomers containing a urethane compound and an acrylic acid ester as a core of the conductive particle, the resin particle having an acrylic resin as a main component, having a maximum compression deformation ratio of 60% or more, and needing a load of less than or equal to 60 mN for a compression deformation by 60%; and
a conductive material bonded to a surface of the resin particle.
12. The anisotropic conductive adhesive according to claim 11 , wherein the adhesive material includes an epoxy material defined as a thermosetting resin and a hardener for hardening the epoxy material.
13. The anisotropic conductive adhesive according to claim 11 , wherein the anisotropic conductive adhesive is molded in a film form.