Patent GB-1421400-A (GB)
Title: Photopolymer process
IPC: G03F7/038
Filed: 1973-11-07
Abstract: 1421400 Producing lithographic plates HERCULES Inc 7 Nov 1973 [9 Nov 1972] 51648/73 Heading C3G [Also in Division G2] A layer of an oleophilic polymer comprising an extralinear -CR<SP>1</SP>=CR<SP>2</SP>CHR<SP>3</SP>- olefinic grouping wherein R<SP>1-3</SP> may be hydrogen and having on or in its surface a sensitizer for photoinduced oxidation to produce a polymer hydroperoxide is imagewise exposed to light of wavelength 2000-12-000  in the presence of oxygen (e.g. as air). A metal catalyst to convert the hydroperoxide to epoxide and a phenolic antioxidant to prevent thermal oxidation may also be present. A graft polymer is formed in the image areas after removal of the sensitizer by (a) reaction of the polymer hydroperoxide with a vinyl monomer in the presence of heat, redox catalyst or reducing agent or (b) by reaction of the polymer epoxide with a polymer reactant. The graft image may be treated with a dye or a chromium, zinc or zirconium salt, or may be amplified by salt formation or covalent bonding. The oleophilic polymer may be propoxylated bisphenol-A fumarate polyester resin modified with 2,3-dimethyl-1,3-butadiene and crosslinked with a trifunctional isocyanate; ethylenepropylene-ethylidenenorborene terpolymer rubber; hydrolysed polyvinyl alcohol, phenoxy resin or hydroxypropyl cellulose modified with 1,2,4 - trimethyl - 4 - chlorocarbonyl cyclohexene; phenoxy resin modified with 4,5- dimethyl-4-hexen-1-ol; ethylene-vinyl alcohol copolymer modified with p-(2,3-dimethyl prop- 2-enyl) benzoyl chloride; vinyl chloride-vinyl alcohol copolymer modified with #-(5-methyl-2- furyl)-propionyl chloride; or isophthalic polyester modified with 2,3-dimethyl-1,3-butadiene. The vinyl monomer may be acrylamide, acrylic acid, dimethylacrylamide, hydroxymethylacrylamide, polyethylene glycol diacrylate, glycidyl acrylate, vinylbenzyl chloride, sodium 2 - sulphoethylmethacrylate, methacryloxyethyltrimethyl ammonium chloride or methylsulphate, N,N - dimethylaminoethy] acrylate or methacrylate, N,N-diethylaminoethyl acrylate or methacrylate, hydroxyethyl acrylate or methacrylate, glycerol acrylate or methacrylate, hydroxyethyl acrylamide, methacrylic acid, itaconic acid, sodium ethylenesulphonate, sodium sulphoethylacrylate, sodium sulphopropylmethacrylate, sodium sulphopropylacrylate, sodium 2 - acrylamido - 2- methylpropanesulphonate, acrylyl chloride, methacrylyl chloride or itaconyl chloride. The polymeric reactant may be polyethylenimine, polyaminoethyl acrylate or methacrylate, polyaminorpopyl acrylate or methacrylate, polyacrylic acid, polymethacrylic acid, or polyitaconic acid. A cationic amplification agent may be polyethylenimine, polymethacryloxyethyltrimethylammonium methylsulphate, polymer or copolymer of N,N- dimethylaminoethyl acrylate or methacrylate or N,N - diethylaminoethyl acrylate or methacrylate, metal salt, sodium hydroxide, ethylene diamine or diethylenetriamine. An anionic amplification agent may be sodium sulphopropylacrylate - acrylamide copolymer; polyacrylic acid, polysodium acrylate or methacrylate, polysodium ethylene sulphonate, polyitaconic acid, polymethacrylic acid, polysodium sulphoethylmethacrylate, polysodium sulphopropylacrylate, and polysodium 2- acrylamido 2-methylpropanesulphonate.