Abstract: The present invention provides an epoxy resin composition, comprising:(A) a phenol epoxy resin represented by the following formula (I) ##STR1## wherein each R.sup.1 is the same or different and is independently selected from the group consisting of hydrogen, C.sub.1 to C.sub.6 hydrocarbyl groups, C.sub.6 to C.sub.10 aromatic groups, and C.sub.1 to C.sub.6 hydrocarbyl-substituted C.sub.6 to C.sub.10 aromatic groups,each R.sup.2 is the same or different and is independently selected from the group consisting of hydrogen, C.sub.1 to C.sub.6 hydrocarbyl groups, C.sub.6 to C.sub.10 aromatic groups, and C.sub.1 to C.sub.6 hydrocarbyl-substituted C.sub.6 to C.sub.10 aromatic groups, ##STR2## wherein R.sup.3 is selected from the group consisting of hydrogen, C.sub.1 to C.sub.6 hydrocarbyl groups, C.sub.6 to C.sub.10 aromatic groups, and C.sub.1 to C.sub.6 hydrocarbyl-substituted C.sub.6 to C.sub.10 aromatic groups, each R.sup.

Abstract: An adhesive for a flexible printed circuit board and the method of preparing the same where the adhesive displays excellent migration inhibition, moisture adsorption resistance, and superior peeling strength, heat resistance, solvent resistance, chemical resistance, flexibility, and electrical properties. The adhesive is prepared by pre-polymerizing an epoxy resin, a COOH-containing rubber, a filler, and a primary catalyst in a solvent using a tertiary amine as a primary catalyst to form a prepolymer, followed by curing the prepolymer using a curing agent and a curing catalyst. The adhesive is coated on a plastic film, dried and laminated with a copper foil and then cured at an elevated temperature to form a substrate.