Abstract: A photopolymerizable element suitable for use in the production of photorelief printing plates comprises a film or sheet, an adhesive layer and a photopolymerizable layer wherein the adhesive layer comprises a non-photopolymerizable plastics binder and a photopolymerization initiator comprising an admixture of a compound of the formula: ##STR1## preferably 4,4'-bis(dimethylamino)-benzophenone in an amount 0.01 to 2.0% by weight based upon the weight of the binder and another photopolymerization initiator in an amount 0.1 to 7% by weight based upon the weight of the binder.

Abstract: This invention is directed to dual UV and heat activated compositions comprising(1) a liquid, ethylenically unsaturated monomer, oligomer or prepolymer of the formula: ##STR1## wherein R is H or CH.sub.3, R.sub.1 is an organic moiety and n is 2 to 4, hereinafter referred to as the ethylenically unsaturated compound,(2) a photoinitiator, and(3) a substituted or unsubstituted pinacolThe exposure to UV radiation and heat in seriatim or simultaneously results in a cured solid product which can be utilized as coatings, gaskets, sealants, resists and the like.

Abstract: A hologram is produced by causing a crosslinking reaction in accordance with an interference pattern in a recording carrier composed of a polymer containing in its unit structure an aromatic or hetero cyclic ring having a reactive position capable of being substituted by radical.

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: A photopolymerizable mixture for the preparation of printing plates and photoresists is disclosed which contains a polymeric binder, an ethylenically unsaturated polymerizable compound and, as a photoinitiator, a compound having the formula ##STR1## wherein R is an aromatic group which may be substituted and n is 1 or 2.

Abstract: Photosensitive, elastomeric compositions comprising(1) a high molecular weight carboxylated butadiene/acrylonitrile copolymer in which at least about 25% of the carboxyl groups are neutralized with a metal cation of Groups IIA or IIB of the Periodic Table,(2) an ethylenically unsaturated monomer, and(3) a free radical generating system, having outstanding properties as photosensitive elements for flexographic printing plates.

Abstract: Process for preparation of positive images which comprises exposing imagewise a supported layer of a photosensitive composition comprising an alkali-soluble polymeric binder, at least one dihydropyridine compound and at least one hexaarylbiimidazole compound and developing by washing out the exposed image areas. Optionally auxiliary layers can be present between the support and photosensitive layer. The photosensitive elements are useful in preparing positive working printing plates and photoresists.

Abstract: A photopolymerizable coating composition comprising(1) a nongaseous, ethylenically unsaturated, polymerizable compound,(2) a specified nitroaromatic compound, and(3) an organic, radiation-sensitive, free-radical generating systemis useful for making a positive or negative polymeric image on a substrate.

Abstract: A stencil sheet is prepared with an ink-impervious coating of a film forming, solventless olefinic material. The coating includes a photopolymerization initiator, and may be applied to a tissue base in liquid form and thereafter cured by exposure to ultraviolet radiation. The present invention reduces the cost and pollution generation that conventionally attends the preparation of stencil sheets.

Abstract: This invention relates to a series of photoinitiator combinations comprising mixtures of a primary photoinitiator in combination with N-halosuccinimides, N-haloacetanilides and N-halobenzanilides and photopolymerizable composition containing such combinations.

Abstract: In a photopolymerizable composition comprising (1) an addition-polymerizable compound having at least one ethylenically unsaturated double bond and (2) a photopolymerization initiator as essential components, the improvement which comprises that said photopolymerization initiator is a combination of (a) p-dialkylamino aromatic carbonyl compounds represented by the general formulae (1) to (4), (b) 5-isoxazolones represented by the general formula (5) and (c) 2,4,6-substituted-1,3,5-triazines represented by the general formula (6): ##STR1## where R.sup.1, R.sup.2 and R.sup.3 each represents an alkyl group or a substituted alkyl group, which may be the same or different from one another, X represents a substituent having a Hammett's .sigma. value in the range from -0.9 to 0.7, m represents 1 or 2, A.sup.1 and A.sup.

Abstract: A photopolymer initiator system comprising selected semiconductors, reducing agents and oxidizing agents, in combination, and their use in photopolymerization and cross-linking of ethylenically unsaturated monomers.

Abstract: A photosensitive resin composition comprising:(a) a photopolymerizable or photocrosslinkable ethylenically unsaturated compound;(b) a compound of the formula (I): ##STR1## wherein X.sub.1, X.sub.2 and X.sub.3 may be the same or different and each represents a hydrogen atom, a chlorine atom or a bromine atom and at least one of X.sub.1, X.sub.2 and X.sub.3 representing a chlorine atom or a bromine atom; Y represents a --CX.sub.1 X.sub.2 X.sub.3 group where X.sub.1, X.sub.2 and X.sub.3 are as defined above, --NH.sub.2, --NHR', --NR'.sub.2, --SR', --OR' or --R' wherein R' is an alkyl group or an aryl group; R is an alkyl group, an aryl group or an alkenyl group, and may be substituted;(c) a compound of the formula (II): ##STR2## where Z represents the non-metallic atoms necessary to complete a nitrogen-containing heterocyclic ring; R.sub.1 is an alkyl group or a substituted alkyl group; R.sub.2 is an alkyl group, an aryl group or a substituted aryl group; and(d) a dye precursor.

Abstract: A hologram is produced by causing a crosslinking reaction in accordance with an interference pattern in a recording carrier composed of a polymer containing in its unit structure an aromatic or hereto cyclic ring having a reactive position capable of being substituted by radical.

Abstract: A photosensitive material is described which comprises a base and a solid photosensitive layer comprising a photopolymerizable compound and a photopolymerization initiating mixture consisting of an oxime ester, a photopolymerization initiator and a p-dialkylaminobenzene of the formula ##STR1## wherein R.sup.1 and R.sup.2 are lower alkyl, R.sup.3 is hydrogen, alkyl, alkoxy or N(R.sup.1) (R.sup.2) and X is --CO--, --CS--, CH.sub.2, or --CH(OH)--.Synergistic photocuring sensitivity is obtained by said oxime ester in admixture with said p-dialkyl aminobenzene compound.

Abstract: A photosensitive element for preparing negative tonable images which comprises a support bearing a layer of a photosensitive composition comprising a thermoplastic binder, at least one dihydropyridine compound and at least one hexaarylbiimidazole compound. Optionally softeners and sensitizer can be present in the photosensitive layer. The photosensitive element is useful in preparing negative tonable images.

Abstract: 2-Arylnaphtho[1,8-bc]furan-5-ones represented by general formula (I): ##STR1## wherein G represents a substituted phenyl group, an unsubstituted or substituted 1-naphthyl group and an unsubstituted or substituted 2-naphthyl group, with the substituents being selected from the group consisting of a straight chain or branched chain alkyl group having 1 to 5 carbon atoms, a straight chain or branched chain alkoxy group having 1 to 3 carbon atoms and a halogen atom; are disclosed as well as photopolymerizable compositions containing at least one of the above compounds as a photopolymerization initiator for addition polymerizable ethylenically unsaturated compounds.

Abstract: Photopolymerizable compositions for the production of printing plates and relief plates, consisting essentially of a photoinitiator-containing mixture of olefinically unsaturated photopolymerizable compounds with polymeric binders, contain up to 1% by weight of a compound having the structural element of anthrone, e.g. bianthrone and 9,9'-bianthryl, which results in an improved relief image in the production of relief plates.

Abstract: Photosensitive, elastomeric compositions containing(1) a high molecular weight butadiene/acrylonitrile copolymer,(2) a low molecular weight butadiene polymer,(3) an ethylenically unsaturated monomer, and(4) a free-radical generating systemhave outstanding properties as photosensitive coatings for flexographic printing plates. When the combination of high and low molecular weight polymers contains at least about 2% by weight of carboxyl groups, the compositions are processable in aqueous or semiaqueous basic solutions.