DRY FILM PHOTORESIST Russian patent published in 2002 - IPC

FIELD: microelectronics. SUBSTANCE: invention provides dry film photoresist for protective coatings on printed cables and flexible boards. Water-alkali development-type photoresist contains carboxyl-containing polymer, polar oligomer-methacrylated epoxide resin based on 4,4'- dihydroxy(2,2-diphenylpropane) with molecular weight 540-600, crosslinking oligomers, inhibitor, photoinitiating mixture of benzophenone and 4,4'- bis(dimethylamino)benzophenone, said carboxyl-containing polymer containing unsaturated polyamido acid having general formula I: (I), in which R represents methacryloyl radical, R' oxygen atom or methylene radical, n= 12-35, with molecular weight (6.5-18.3) x 10³. Photoresist is well developed by 1-3-% aqueous solutions of weak alkalis, e.g. alkali metal carbonates. When thermally hardened, material reveals elevated temperature resistance and flexibility. EFFECT: enabled use for critical microelectronic ware. 2 tbl