Abstract: A photopolymerizable composition comprised of an addition polymerizable material, a photoinitiator, a thermal addition polymerization inhibitor and a polymeric binding agent. The addition polymerizable material is comprised of a defined monoethylenically unsaturated acrylate and one or more non-gaseous compounds having at least two terminal ethylenic groups. The photopolymerizable composition displays superior flexibility and develops and strips more efficiently when compared to a like composition but in the absence of the acrylate. The photopolymerizable composition may be in the form of sheet or roll on a film support which can be laminated to a substrate and can be used in the preparation of printed circuit boards.

Abstract: An automatic system that feeds, laminates, unloads, stores and transfers laminated panels to subsequent processing for use in the electronics industry includes an automatic laminator that operates with a single roll of photoresist dry film to effect single wrap around lamination of each of a plurality of panels in succession and removal of the polyethylene protective cover sheet, and further includes a buffer/interface unit that is operative during a post lamination period to provide a holding area for the laminated panels to allow them to chemically stabilize prior to imaging, and in addition, is operative after the panel has stabilized to translate each of the panels, in turn, from a vertical to a horizontal position and deliver it to the infeed portion of an exposure machine that is mated with it.

Abstract: Compositions containing a polymerizable, curable or crosslinkable component, a photoinitiator, a colorformer capable of changing color upon contact with a suitable activator and a latent activator containing an organic halide will become insoluble and change color under the influence of actinic radiation. The organic halide is a carbonylic compound such as an aliphatic or cycloaliphatic ketone or an ester or amide of a dicarboxylic acid. The compositions are useful to make resists used in the electronics industry to manufacture printed circuits.

Abstract: A photopolymerizable composition comprised of an addition polymerizable material, a photoinitiator, a thermal addition polymerization inhibitor and a polymeric binding agent. The addition polymerizable material is comprised of a defined monoethylenically unsaturated acrylate and one or more non-gaseous compounds having at least two terminal ethylenic groups. The photopolymerizable composition displays superior flexibility and develops and strips more efficiently when compared to a like composition but in the absence of the acrylate. The photopolymerizable composition may be in the form of sheet or roll on a film support which can be laminated to a substrate and can be used in the preparation of printed circuit boards.

Abstract: An apparatus for automatically laminating photoresist dry film onto each of a plurality of panels stacked upright in a panel feed unit with a 10.degree. slant counterclockwise from the vertical, the film being characterized by being easily contaminated, limp and tacky although peelable thereby enabling the use of a polyethylene protective coating, includes a film feed bar for pulling the film from a roll into a laminating station on a 10.degree. upward slant, the polyethylene coating being wound on a take-up roll, and further includes a film hold bar, a film hold cutoff bar and a film cutoff knife for cutting the film precisely to the length required for folding the film over the panel on both sides with no overlap. A panel pick-up unit picks up each of the panels in succession and moves it down into engagement with a transverse center line on the film, through a laminating nip and between heated laminating rolls, delivery belts and cooperating lugs moving the laminated panel to a delivery stack.

Abstract: Compositions containing a polymerizable, curable or crosslinkable component, a photoinitiator, a fluoran colorformer and a latent activator that releases or promotes the release of a Lewis acid, will become insoluble and change color under the influence of actinic radiation. These compositions are particularly useful to make dry film photoresists, which are widely used in the electronics industry to manufacture printed circuits.

Abstract: Photopolymerizable screen printing inks comprising a hydroxyalkyl acrylate-type monomeric material, a polyester binder and a free-radical initiating system, such inks having a viscosity of from 5,000 to 200,000 centipoises, an acid number of from 0 to 120 and a thixotropic index of from 1 to 4. The process of using such inks to treat substrates, such as in making printed circuits, which includes the steps of screen printing the photopolymerizable ink on the substrate; exposing the ink to actinic radiation to cure the ink and to form a resist; and permanently modifying the exposed areas on the substrate. The resist may thereafter be removed by dissolving in aqueous dilute alkali or an organic solvent.

Abstract: A new photopolymerizable composition which contains an addition polymerizable monomer, a photoinitiator, and an improved binding agent which is a polymer of three types of monomeric materials, namely, a styrene-type monomer, an acrylate monomer, and an alpha, beta-unsaturated carboxyl-containing monomer. These compositions are useful for flexible photopolymerizable films which, after exposure, may be developed in aqueous alkaline solutions. These films may be used as photo-resists, screen stencils and printing plates.

Abstract: The free bases of various amino dyestuffs, such as the amino derivatives of triarylmethane and xanthene dyestuffs form stable solutions with organic halides and a matrix, such as a film-forming binder. Dry films of such compositions are lightly colored; upon exposure to actinic light, the dyestuffs become intensely colored. The combination of dyestuff free base and organic halide is particularly useful in conjunction with photopolymerizable compositions to denote the polymerized portions of a dry film photoresist and to enable the use of thicker films or coatings of liquid photopolymerizable compositions than were previously useful.

Abstract: Highly durable coatings are formed by the photopolymerization of screen printing inks containing aryloxyalkyl acrylate monomers or prepolymers, a polymerizable diluent and a free-radical initiating system, such inks having a viscosity of 5,000 to 200,000 centipoises and a thixotropic index of from 1 to 6. The photopolymerizable inks are useful for coating substrates, such as printed circuits, and serve as solder masks and resists for electroless plating, electroplating and etching.

Abstract: Highly durable coatings are formed by the photopolymerization of screen printing inks containing aryloxyalkyl acrylate monomers or prepolymers, a polymerizable diluent and a free-radical initiating system, such inks having a viscosity of 5,000 to 200,000 centipoises and a thixotropic index of from 1 to 6. The photopolymerizable inks are useful for coating substrates, such as printed circuits, and serve as solder masks and resists for electroless plating, electroplating and etching.

Abstract: A process for making photoresists which comprises preparing a photopolymerizable layer of an addition polymer, an initiator system, and a polymerizable inhibitor, using a preformed macromolecular binding agent which is a copolymer of a first monomeric material containing one or more non-acidic vinyl-type compounds and a second monomeric material containing one or more alpha,beta-unsaturated carboxyl-containing monomers, wherein the ratio of the first monomer to the unsaturated carboxylic-containing monomer is sufficient to render the binding agent soluble in a dilute alkaline solution; thereafter exposing a portion of the photopolymerizable layer to actinic light; and washing said layer with a dilute aqueous alkaline solution to dissolve the unexposed portion of the photopolymerizable layer. Preferably, the photopolymerizable layer is supported on a metallic substrate prior to said washing step.

Abstract: Photopolymerizable screen printing inks comprising a hydroxyalkyl acrylate-type monomeric material, a polyester binder and a free-radical initiating system, such inks having a viscosity of from 5,000 to 200,000 centipoises, an acid number of from 0 to 120 and a thixotropic index of from 1 to 4. The process of using such inks to treat substrates, such as in making printed circuits, which includes the steps of screen printing the photopolymerizable ink on the substrate; exposing the ink to actinic radiation to cure the ink and to form a resist; and permanently modifying the exposed areas on the substrate. The resist may thereafter be removed by dissolving in aqueous dilute alkali or an organic solvent.