Loading patent…
AssigneeMorton International, Inc.
InventorsJames Rath, William Luong-Gia Tran, Kathy M. Flynn, Vinai Ming Tara, Thomas A. Koes, Vincent J. Nizzo
Estimating the term…
In a process for fabricating a multilayer printed circuit board with permanent innerlayers of photoresist, the photoimageable composition used to form the hard permanent layer comprises a polymerizable acrylate monomer; an oligomer formed by the reaction of an epoxy resin and an acrylic or methacrylic acid; a photosensitive, free radical generating initiator for polymerization of the acrylic monomer and oligomer; a curable epoxy resin; a curing agent for the epoxy resin; and, optionally, a crosslinking agent reactive with hydroxyl groups. After exposure and development of a layer of the photoimageable composition and etching of the underlying metal layer on a board, the resultant photoresist is left on the circuitry traces. The innerlayers of photoresist are stacked in a press where it initially conforms under heat and pressure to fill voids between the innerlayers and then cures to permanence.
A multilayer printed circuit board fabricated with a plurality of permanent printed innerlayers each of which comprises a board of dielectric material, a metal layer on said board, and a light- and heat-cured photoresist on said metal layer, said photoresist comprising:
Dependencies are inferred from the claim text.