PHOTO-CURABLE RESIN LAMINATE AND METHOD OF PRODUCING PRINTED WIRING BOARD USING THE SAME.

摘要

A photo-curable resin laminate composed of a support and a photo-curable resin layer disposed on one of the surfaces of the support, wherein the photo-curable resin layer has: (a) a viscosity of 10<4> to 5 x 10<5> P at 90 DEG C, (b) a thickness of 30 to 150 mu m, and (c) an UV transmissivity of 40 to 95 % at a wavelength of 365 nm. This photo-curable resin layer is laminated under pressure on both surfaces of a metal-coated insulating plate having small through-holes having a 0.5 mm or smaller inner diameter in such a manner that the side of the photo-curable resin layer comes into contact with both surfaces of the metal-coated insulating plate, the photo-curable resin layer enters partially inside the inner peripheral edge of the open portion of each through-hole so as to define a photo-curable resin layer extending from this edge along the inner wall of the through-hole in a predetermined depth on the inner wall surface. The curable resin layer which is in close contact from the inner peripheral edge of the opening of the through-hole to the inner wall is formed by exposure and development to give the coating of the opening of the through-hole free from any coating defect. When an unnecessary conductor layer other than the conductor layer of a desired pattern is thereafter removed with an etchant, a printed wiring board having the small diameter through-holes and extremely high reliability of conduction between both surfaces by the through-holes can be produced.