Abstract: Aqueous processable photopolymerizable compositions containing (a) a cobinder system, (b) an acrylated urethane monomeric component; (c) a photoinitiator system; and (d) a thermal cross-linking agent are disclosed, which as cured compositions, are flexible and can be used as permanent coatings for the protection of printed circuitry.

Abstract: A photopolymerizable composition comprising(a) a monomeric componment which is a half acryloyl ester of bisphenol A epoxy monomer;(b) an initiating system activated by actinic radiation; and(c) a preformed macromolecular elastomeric polymer binder.

Abstract: A photopolymerizable composition comprising(a) a monomeric component which is a half acryloyl ester of bisphenol A epoxy monomer;(b) an initiating system activated by actinic radiation; and(c) a preformed macromolecular elastomeric polymer binder.

Abstract: A storage stable photopolymerizable composition is disclosed comprising polymeric acid binder with an acid number of at least 45 and a pKa value of at least 5, monomer, photoinitiator and an aldehyde resin precursor.

Abstract: A simplified method for photoimaging a photosensitive layer produces in situ a radiation-opaque photomask on the photosensitive layer or on a cover sheet of the layer. A nonvisible latent image is toned and the toner is transferred to a layer or cover sheet to form an actinic radiation-opaque photomask.

Abstract: A dry-developing dry film resist is provided comprising a photopolymerizable layer preferably sandwiched between a support sheet and a cover sheet, the layer comprising polymerizable monomer in excess of the absorptive capacity of the layer, photopolymerization initiator, and binder component of a plurality of polymers, at least one of these polymers being incompatible so as to be present as a dispersion in the layer to reduce the cohesive strength of the layer. The layer is developed by peeling away the support sheet, the unexposed area of the layer adhering to the support sheet and the exposed area adhering to the substrate to which it was laminated to form a resist image against such treatments as etching, plating and soldering, especially to make a printed circuit.

Abstract: A dry-developing dry film resist is provided comprising a photopolymerizable layer preferably sandwiched between a support sheet and a cover sheet, the layer comprising polymerizable monomer in excess of the absorptive capacity of the layer, photopolymerization initiator, and binder component of a plurality of polymers, at least one of these polymers being incompatible so as to be present as a dispersion in the layer to reduce the cohesive strength of the layer. The layer is developed by peeling away the support sheet, the unexposed area of the layer adhering to the support sheet and the exposed area adhering to the substrate to which it was laminated to form a resist image against such treatments as etching, plating and soldering, especially to make a printed circuit.

Abstract: A radiation sensitive element comprising a support bearing a layer of photopolymerizable composition which comprises (1) at least one addition polymerizable ethylenically unsaturated compound, (2) an initiator activatable in the ultraviolet to visible region of the spectrum, and (3) at least 20% by weight of a polymeric binder containing at least 5% by weight of acrylonitrile, the composition having present at least 5% by weight halogen based on the total weight of composition covalently bonded to an aromatic moiety of at least one of said components of the composition and/or a conjugated vinyl component. The elements withstand soldering and are flame retardant and are useful as solder masks.