Abstract: A silver halide sensor type polymerizable light-sensitive material is disclosed. The material is comprised of a support having a silver halide photographic emulsion layer and a polymerizing layer adjacent to the emulsion layer. The polymerizing layer contains a nongaseous ethylenically unsaturated compound capable of undergoing addition polymerization upon reduction of the silver halide with a reducing compound. The material is capable of producing printing plates having good inking property and good printing durability. The material maintains the sensitivity and high resolving power of a silver halide photographic light-sensitive material.

Abstract: A photopolymerizable composition is described, comprising (1) a non-gaseous ethylenically unsaturated compound which has at least two ethylenically unsaturated terminal groups and is capable of forming a polymer, (2) a thermoplastic polymeric binder, (3) a photopolymerization initiator which is activated by actinic radiation, and (4) at least one of certain heterocyclic compounds. The composition is useful as a photoresist for producing printed circuit boards, printing plates, etc., by etching or plating, and the photoresist has superior adhesion with respect to the base.

Abstract: A presensitized printing plate which has a photopolymerizing composition layer provided on at least one side of a support, with the photopolymerizing composition being constituted with (A) a polymer containing in its side chains groups represented by the following general formula (I) and carboxylic groups: ##STR1## (wherein R.sub.1 to R.sub.5 each represents a hydrogen atom, a halogeno group, a carboxyl group, a sulfo group, a nitro group, a cyano group, and amido group, an amino group, or an unsubstituted or a substituted alkyl, aryl, alkoxy, aryloxy, alkylamino, arylamino, alkylsulfonyl or arylsulfonyl group; and Z represents an oxygen atom, a sulfur atom, --NH-- or --NR-- (R=alkyl)), (B) a monomer or an olygomer having at least two polymerizable ethylenically unsaturated double bonds, and (C) a photopolymerization initiator.

Abstract: A photopolymerizable composition is described, which comprises a polymerizable compound containing at least one ethylenically unsaturated double bond and a photopolymerization initiator wherein the photopolymerization initiator is a combination of a 3-keto-substituted cumarin compound and an active halogeno compound. This composition can be easily cured by irradiation with radiation and, therefore, is very useful in the preparation of light-sensitive materials.

Abstract: A photopolymerizable composition having an improved sensitivity, which comprises a polymerizable compound having an ethylenically unsaturated bond and a photopolymerization initiator, wherein said photopolymerization initiator comprises a compound represented by general formula I ##STR1## wherein R.sup.1 and R.sup.2 each represents a hydrogen atom, an alkyl group, a substituted alkyl group, an aryl group, a substituted aryl group, or an aralkyl group; X represents a substituent having a Hammett's value of not more than 0.7; and Y represents a hydrogen atom, an alkyl group, a substituted alkyl group, an aryl group, a substituted aryl group, an aralkyl group, an acyl group, or an alkoxycarbonyl group and a 1,3,5-triazine compound represented by general formula II ##STR2## wherein R.sup.3, R.sup.4, and R.sup.

Abstract: The present invention relates to a process for producing polyacrylic acid salt granules easily soluble in water characterized in that a water-soluble powder of polyacrylic acid salt is granulated according to fluidized bed granulation method while an aqueous solution of the polyacrylic acid salt of a viscosity of 50-700 c.p.s. is sprayed thereon.

Abstract: A photosensitive composition containing the 2-trihalomethyl-5-aryl-1,3,4-oxadiazole compound represented by the following general formula: ##STR1## wherein X represents a chlorine atom or a bromine atom and A represents a phenyl group, a naphthyl group or a phenyl or naphthyl group substituted by a halogen atom, an alkyl group, an alkoxy group, a nitro group, a cyano group or a methylenedioxy group.

Abstract: Photosensitive compositions containing 2-halomethyl-5-vinyl-1,3,4-oxadiazole compounds represented by the following general formula (I): ##STR1## wherein W represents a substituted or unsubstituted aryl group, X represents a hydrogen atom, an alkyl group or an aryl group, Y represents a fluorine atom, a chlorine atom or a bromine atom, and n represents an integer of 1 to 3.

Abstract: Compounds represented by the following general formula: ##STR1## wherein W represents a phenyl group, a phenyl group substituted with a member selected from the group consisting of a halogen atom, a nitro group, a cyano group, an alkyl group containing 1 to 3 carbon atoms and an alkoxy group containing 1 to 4 carbon atoms, with the number of the substituents being 1 or 2 when said substituent is a halogen atom and 1 when said substituent is other than halogen, or an unsubstituted naphthyl group, and said phenyl group may take the form of ##STR2## X represents a hydrogen atom, an unsubstituted phenyl group or an alkyl group containing 1 to 3 carbon atoms, Y represents a halogen atom, and n represents an integer of 1 to 3. These compounds are useful as photo-initiators.

Abstract: A photosensitive image forming element comprising: a support; photosensitive layer therein which is rendered alkali-soluble upon exposure and which comprises (i) an azide compound having at least one alkali-soluble group in its molecular structure, and (ii) a polyamide.

Abstract: A photosensitive lithographic printing plate comprising a support having thereon a photosensitive layer composed of a photosensitive diazo-oxide resin containing a hydroxystyrene unit and a hydroxystyrene unit having an o-quinoediazide group bonded through the oxygen of the hydroxystyrene. The photosensitive layer can contain an alkali-soluble resin. The photosensitive lithographic printing plate is stable mechanically, provides a large difference in solubility between the exposed areas and the unexposed areas of the layer, and has improved printability and sensitivity.

Abstract: A light-sensitive lithographic printing plate comprising a support with a hydrophilic surface having thereon a light-sensitive layer comprising a light-sensitive polyester containing o-quinonediazido groups as terminal groups.