US 5,830,389 A · Electrically conductive compositions and methods for the preparation and use thereof

Abstract

Electrically conductive adhesive compositions and methods for the preparation and use thereof, in which a solder powder, a chemically protected cross-linking agent with fluxing properties and a reactive monomer or polymer are the principal components. Depending upon the intended end use, the compositions comprise three or more of the following: a relatively high melting metal powder; solder powder; the active cross-linking agent which also serves as a fluxing agent; a resin; and a reactive monomer or polymer. The compositions are useful as improved conductive adhesives, such as for attaching electrical components to electrical circuits; the compositions comprising metal powder are ideally suited for creating the conductive paths on printed circuits. The compositions for forming conductive paths may first be applied to a substrate in the desired pattern of an electrical circuit, and then heated to cure it. During heating, the action of the cross-linking agent and optional reactive monomer or polymer within the mixture fluxes the metals, enabling sintering to occur between the metal powder and the solder powder.

Claims26

Dependent claims

A composition of matter comprising:

greater than 0 up to 65% of a high melting point metal, wherein the high melting point metal is selected from the group consisting of copper, silver, aluminum, gold, platinum, palladium, beryllium, rhodium, nickel, cobalt, iron, molybdenum, and alloys thereof;
6-65% of a solder, wherein said solder is selected from the group consisting of Sn, Bi, Pb, Cd, Zn, Ga, In, Te, Hg, To, Sb, Se, and alloys thereof;
0-45% of a resin;
0.01-61% of a chemically protected cross-linking agent with fluxing properties which is reactive only at or near the time at which the solder is melted,
wherein said chemically protected cross-linking agent is an acid or a strong base, wherein said acid or strong base is selected from the group consisting of anhydrides, carboxylic acids, amides, amines and phenols, and
wherein said acid or strong base is protected by a protecting group selected from the group consisting of carboxylic acids, alcohols, glycols and polyols;
and
0-50% of a reactive monomer or polymer,
wherein all percentages referred to herein are based on volume.

6 more elements

Dependencies are inferred from the claim text.

Electrically conductive compositions and methods for the preparation and use thereof

Life of this patent

Electrically conductive compositions and methods for the preparation and use thereof

Life of this patent

Abstract

Claims26