Patent ID: 6074803
Filing Date: 2000-06-13
Classification: H05K

Abstract:
A process for manufacturing a multilayer circuit board, the process comprising the steps of:(A) providing a first layer which comprises an insulating sub-layer and a conducting sub-layer;(B) providing a first resin component that is substantially free of unreacted epoxide groups and has photopolymerisable groups;(C) providing a resin mixture that includes a free-radical polymerization photoinitiator and a molecule having unreacted epoxide groups;(D) combining the first resin component and the resin mixture to form a resin composition having from 50 weight percent to 94 weight percent of the first resin component and from 5 weight percent to 49 weight percent of the molecule having unreacted epoxide groups wherein the weight percentages are based upon the total weight of the resin composition;(E) applying the resin composition to a surface of the conducting sub-layer to form a resin composition layer that is etchable;(F) forming areas of the resin composition layer that are etch-resistant and leaving areas of the resin composition layer that are etchable;(G) contacting the etchable areas of the resin composition layer with an aqueous developing composition to remove the etchable areas of the resin composition layer to reveal areas of the conducting sub-layer;(H) etching the revealed areas of the conducting sub-layer;(I) contacting a second layer with a surface of the etch-resistant areas of the resin composition layer; and(J) adhering the first layer to the second layer to form the multi-layer circuit board.