Anisotropic conductive film, connection structure and method of producing the same
An anisotropic conductive film is obtained by dispersing conductive particles in an insulating adhesive composition including a (meth)acrylate-based monomer composition, a radical polymerization initiator, and a film-forming resin. The (meth)acrylate-based monomer composition includes a (meth)acrylate-based monomer which has a cyclic ester residue or a cyclic amide residue represented by the formula (1): R1 is a hydrogen atom or a methyl group; R2 is an alkylene group or an alkyloxy group; R3 is an alkyl group, an alkylene group, an aryl group, or a halogen atom; n is an integer of 0 to 3; R4 is absent or an alkylene, dotted lines on both sides of R4 jointly represent a single bond; X1 is absent, or an oxygen atom or a carbon atom; and X2 is an oxygen atom, a nitrogen atom, or a sulfur atom.
1. An anisotropic conductive film comprising an insulating adhesive composition and conductive particles that are uniformly dispersed in the insulating adhesive composition, wherein:
the insulating adhesive composition comprises a (meth)acrylate-based monomer composition, a radical polymerization initiator, and a film-forming resin;
the (meth)acrylate-based monomer composition includes a (meth)acrylate-based monomer having a cyclic ester residue or a cyclic amide residue; and
the (meth)acrylate-based monomer having a cyclic ester residue is represented by the following constitutional formula (2) or (3):
where R1 is a hydrogen atom or a methyl group.
2. The anisotropic conductive film according to claim 1 , wherein the (meth)acrylate-based monomer having a cyclic amide residue is represented by the following constitutional formula (1):
where in the formula, R1 is a hydrogen atom or a methyl group; R2 is an alkylene group or an alkyloxy group; R3 is an alkyl group, an alkylene group, an aryl group, or a halogen atom; n is an integer of 0 to 3; R4 is absent or an alkylene group which may be substituted by an oxygen atom, wherein when R4 is absent, dotted lines on both sides of R4 jointly represent a single bond; X1 is absent, or an oxygen atom or a carbon atom, wherein when X1 is absent, solid lines on both sides of X1 jointly represent a single bond; and X2 is a nitrogen atom.
3. The anisotropic conductive film according to claim 1 , wherein the conductive particles are electroless-plated metal-coated resin particles having a size of 1 to 20 μm.
4. The anisotropic conductive film according to claim 1 , wherein the (meth)acrylate-based monomer composition is present in the insulating adhesive composition in an amount of 1 to 50% by mass based on a total mass of the insulating adhesive composition.
5. A method for producing an anisotropic conductive film, comprising uniformly dispersing and mixing conductive particles in an insulating adhesive composition including a (meth)acrylate-based monomer composition, a radical polymerization initiator, and a film-forming resin; and coating the resulting mixture on a release film and then drying the mixture, wherein
a (meth)acrylate-based monomer having a cyclic ester residue or a cyclic amide residue is used as the (meth)acrylate-based monomer composition; and
the (meth)acrylate-based monomer having a cyclic ester residue is represented by the following constitutional formula (2) or (3):
where R1 is a hydrogen atom or a methyl group.
6. The production method according to claim 5 , wherein the (meth)acrylate-based monomer having a cyclic amide residue is represented by the following constitutional formula (1):
where in the formula, R1 is a hydrogen atom or a methyl group; R2 is an alkylene group or an alkyloxy group; R3 is an alkyl group, an alkylene group, an aryl group, or a halogen atom; n is an integer of 0 to 3; R4 is absent or an alkylene group which may be substituted by an oxygen atom, wherein when R4 is absent, dotted lines on both sides of R4 jointly represent a single bond; X1 is absent, or an oxygen atom or a carbon atom, wherein when X1 is absent, solid lines on both sides of X1 jointly represent a single bond; and X2 is a nitrogen atom.
7. The method according to claim 5 , wherein the (meth)acrylate-based monomer composition is present in the insulating adhesive composition in an amount of 1 to 50% by mass based on a total mass of the insulating adhesive composition.
8. A connection structure having a terminal of a first electronic part and a terminal of a second electronic part that are bonded by anisotropic conductive connection through the anisotropic conductive film according to claim 1 .
9. A method for producing a connection structure wherein a terminal of a first electronic part and a terminal of a second electronic part are bonded by anisotropic conductive connection, the method comprising:
temporarily adhering the anisotropic conductive film according to claim 1 on the terminal of the first electronic part;
temporarily disposing the second electronic part on the temporarily adhered anisotropic conductive film so that the terminal of the first electronic part and the terminal of the second electronic part are opposed to each other; and
heating and pressurizing the temporarily disposed second electronic part, thereby connecting the terminal of the first electronic part and the terminal of the second electronic part to each other by anisotropic conductive connection.