Abstract: A photoimageable composition and process for use of the same. The composition comprises a binder that is a mixture of a phenolic resin and a multifunctional epoxy or vinyl compound and a curing system comprising a photoactive compound capable of generating a curing catalyst capable of crosslinking the binder components. The process for use of the composition comprises application of the composition to a substrate, drying of the same, exposing the dried coating to activating radiation, curing the binder in light exposed areas, developing the coating and thermally curing the developed image. The composition is especially useful as a solder mask.

Abstract: A photoimageable composition and process for use of the same. The composition comprises a binder that is a mixture of a phenolic resin and a multifunctional epoxy or vinyl ether pound and a curing system comprising a photoactive compound capable of generating a curing catalyst capable of crosslinking the binder components. The process for use of the composition comprises application of the composition to a substrate, drying of the same, exposing the dried coating to activating radiation, curing the binder in light exposed areas, developing the coating and thermally curing the developed image. The composition is especially useful as a solder mask.

Abstract: A light sensitive composition and process for using said composition. The light sensitive composition comprises a phenolic resin, a multifunctional epoxy or vinyl compound, a photoinitiator and a thermal crosslinking agent. The process for using the same comprises application of the light sensitive composition to a substrate, drying of the same, exposing the dried coating to activating radiation, partially heat curing the coating, developing the coating and thermally curing the developed image. The composition is especially useful as a solder mask.

Abstract: A photoresist composition comprising a sensitizer in a binder that is a naphthol polymer alone or mixed with another compatible resin such as a novolak resin or a polyvinyl phenol. The use of the naphthol resin as a portion of the binder increases the heat distortion temperature of the photoresist composition.

Abstract: This invention is directed to processes for using a light sensitive photoresist material in the manufacture of an article having a surface permanently modified in an image pattern. The process comprises applying the photoresist to a substrate through a screen, preferably as a continuous, incompletely imaged layer and thereafter, imaging and developing to provide a relief image in the photoresist layer and treating the substrate to provide a permanent image in the finished article. The process is particularly useful in the manufacture of printed circuits. The process is believed to be a departure from conventional processes in the step of screening a light sensitive photoresist material over a substrate.

Abstract: Rosinous material is added to photoresist compositions to improve flexiblity, rheology and other physical properties. The rosinous material may be a rosin or a hydrogenated, esterified or neutralized derivative of a rosin. Particular advantages are achieved when the photoresists also contain a polyvinyl alkyl ether.