SINGLE COMPONENT TYPE EPOXY ADHESIVE AGENT FOR REINFORCING JOINT STRENGTH IN SOLDER PASTE TO PREVENT BREAK IN WIRE BY DISTORTION OR IMPACT WITHOUT REQUIRING ADDITIONAL PROCESS OR APPARATUS

摘要

PURPOSE: A single component type epoxy adhesive agent(44) is provided to improve the joint strength of a solder paste(30) thereby preventing the separation between a connection point(12) and a lead(22) in a circuit board(10) and further preventing break in wire caused by distortion or impact, without requiring additional process or apparatus. The epoxy adhesive agent also improves the reliability in final products and being economical. By using the adhesive agent, a printed circuit board can have more neat and clean appearance, since the adhesive agent is applied to the lower part of parts(20). CONSTITUTION: The single component type epoxy adhesive agent comprises: 100pts.wt of an epoxy resin; 5-55pts.wt of a potential hardening agent; 2-25pts.wt of an inorganic filler and a thixotropic agent; and 3pts.wt of a dye. The epoxy resin is selected from a bisphenol A type resin having a viscosity of 7000-20000cps at 25deg.C, an epoxy equivalent amount of 170-240g/eq and a chlorine portion of 1000ppm or less, a phenol novolac epoxy type resin having a viscosity of 1000-10000cps at 25deg.C, an epoxy equivalent amount of 140-200g/eq, and a cresol novolac epoxy type resin having an epoxy equivalent amount of 150-250g/eq and a softening point of 60-100deg.C. The potential hardening agent should be possible for a long-term storage at a given temperature without causing changes in its characteristics, show rapid chemical reaction upon heating to a certain temperature, and be selected from amine, imidazole, modified amine and modified imidazole compounds.