| 摘要 |
<p>1381119 Positive working photo-sensitive materials KALLE AG 29 Dec 1971 [30 Dec 1970] 60420/71 Heading G2C [Also in Division B6] A positive-working, photo-sensitive composition comprises a non-light-sensitive polymer having acid substituents and a minor amount of a light-sensitive compound or polymer containing at least one six-membered N-heterocyclic nucleus substituted by or fused to at least one heterocyclic nucleus. Specified polymers are those containing carboxylic, phosphoric or sulphonic acid groups or N-arylsulphenyl-urethane groups; preferably copolymers of acrylic or methacrylic acid. Specified light-sensitive compounds are acridenes, benzecridines, phenazines, benzphenazines, quinoxalines and 2, 3-diphenyl-pyrazines or-dihydropyrazines and the specified light-sensitive polymer is the reaction product of a methyl methacrylate/ glyciolyl acrylate copolymer and b-carboxy-4', 4"- dimethoxy-2, 3-diphenyl quinoxaline. The composition may be coated on a metal, Cu/Al bimetallic Al/Cu/Cr tri-metallic or polyester support and imagewise exposed and developed (e.g. with ethylene glycol monoethyl ether, water and sulphuric acid) to produce a printing plate. Alternatively, stencils may be produced if a stencil screen support is used or colour proofs produced if a dye is added to the composition and a transparent polyester support is used. The composition may be overcoated with a polyvinyl alcohol layer. Plasticizers such as dibutylphthalate may be added to the composition. The positive resist, when used as a printing plate, may be hardened by heating to above 180‹C.</p> |
