# US 4,394,435 A · Syndiotactic polybutadiene composition for a photosensitive printing plate > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 4,394,435 A - Document ID: US4394435A - Status: Granted - Kind: A - Application number: 06/307,360 - Filed: 1981-10-01 - Granted: 1983-07-19 - Earliest claimed: 1981-10-01 - Assignees: Uniroyal, Inc. - Inventors: Milton Farber; John R. Worns - Web page: https://patentgrep.com/patent/US4394435A ## CPC - G03F 7/038: Macromolecular compounds which are rendered insoluble or differentially wettable (G03F7/075 takes precedence; macromolecular azides G03F7/012; macromolecular diazonium compounds G03F7/021) - G03F 7/033: the binders being polymers obtained by reactions only involving carbon-to-carbon unsaturated bonds, e.g. vinyl polymers - Y10S 430/106: Binder containing - Y10S 430/113: with plasticizer - G03F: PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR; (phototypographic composing devices B41B; photosensitive materials or processes for photographic purposes G03C; electrophotography, sensitive layers or processes therefor G03G) - Y10S: TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS ## Abstract A photopolymer elastomeric article designed to be used primarily in a flexographic printing system comprising: a polymer matrix made up of a mixture of syndiotactic 1,2-polybutadiene and cis-1,4-polyisoprene; a photoinitiator, which is a compound, which when irradiated, will initiate polymerization and/or crosslinking; and optionally, 0-3 phr of photopolymerizable, ethylenically unsaturated crosslinking agent, as typified by esters of acrylic or methacrylic acid. ## Claims ### Claim 1 An elastomeric composition for making a printing plate comprising (A) a mixture of syndiotactic 1,2-polybutadiene (SBD) and cis-1,4-polyisoprene (cis-IR); (B) between about 0.1 and 5 phr of a photoinitiator activatable by actinic radiation; and (C) from 0 to 3 phr of a photopolymerizable ethylenically unsaturated compound, wherein (A) comprises 30 to 75% cis-IR and correspondingly 70 to 25% SBD by weight. ### Claim 2 An elastomeric composition for making a printing plate consisting of a mixture of syndiotactic 1,2, polybutadiene (SBD) and cis-1,4, polyisoprene (cis-IR) and between about 0.1 and 5 phr of a photoinitiator activatable by actinic radiation, wherein (A) contains between 30 and 75% by weight of cis-IR and correspondingly, 70 to 25% SBD by weight. ### Claim 3 (depends on 1) An elastomeric article defined in claim 1 wherein (C) comprises from 0.5 to 2.0 phr. ### Claim 4 (depends on 3) The elastomeric composition defined in claim 3 wherein (C) is an ester of acrylic acid. ### Claim 5 (depends on 3) The elastomeric composition defined in claim 3 wherein (C) is an ester of methacrylic acid. ### Claim 6 (depends on 3) The elastomeric composition defined in claim 3 wherein (C) is a photopolymerizable ethylenically unsaturated compound selected from the group consisting of ethylene glycol diacrylate, ethylene glycol dimethacrylate, diethylene glycol diacrylate, diethylene glycol dimethacrylate, 1,4-butanediol diacrylate, 1,4-butanediol dimethacrylate, 1,6-hexanediol diacrylate, 1,6-hexanediol dimethacrylate, trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, or blends thereof. ### Claim 7 (depends on 6) The elastomeric composition defined in claim 6 wherein (C) is ethylene glycol diacrylate. ### Claim 8 (depends on 6) The elastomeric composition defined in claim 6 wherein (C) is ethylene glycol dimethacrylate. ### Claim 9 (depends on 6) The elastomeric composition defined in claim 6 wherein (C) is diethylene glycol diacrylate. ### Claim 10 (depends on 6) The elastomeric composition defined in claim 6 wherein (C) is diethylene glycol dimethacrylate. ### Claim 11 (depends on 6) The elastomeric composition defined in claim 6 wherein (C) is 1,4-butanediol diacrylate. ### Claim 12 (depends on 6) The elastomeric composition defined in claim 6 wherein (C) is 1,4-butanediol dimethacrylate. ### Claim 13 (depends on 6) The elastomeric composition defined in claim 6 wherein (C) is 1,6-hexanediol diacrylate. ### Claim 14 (depends on 6) The elastomeric composition defined in claim 6 wherein (C) is 1,6-hexanediol dimethacrylate. ### Claim 15 (depends on 6) The elastomeric composition defined in claim 6 wherein (C) is trimethylolpropane triacrylate. ### Claim 16 (depends on 6) The elastomeric composition defined in claim 6 wherein (C) is trimethylolpropane trimethacrylate. ### Claim 17 (depends on 6) The elastomeric composition defined in claim 6 wherein (B) is benzophenone. ### Claim 18 (depends on 6) The elastomeric composition defined in claim 6 wherein (B) is C.sub.1 -C.sub.5 alkyl ethers of benzoin. ### Claim 19 (depends on 6) The elastomeric composition defined in claim 6 wherein (B) is benzil. ### Claim 20 (depends on 6) The elastomeric composition defined in claim 6 wherein (B) is C.sub.1 -C.sub.5 alkyl monoketals of benzil. ### Claim 21 (depends on 6) The elastomeric composition defined in claim 6 wherein (B) is 2,2-dimethoxy-2-phenylacetophenone. ### Claim 22 (depends on 1) The elastomeric composition defined in claim 1, wherein (A) is a mixture of 50% sydiotactic polybutadiene and 50% cis-IR; (B) is 2 to 3 phr 2,2-dimethoxy-2-phenylacetophenone; and (C) is 1 to 2 phr hexanediol diacrylate. ### Claim 23 (depends on 22) The elastomeric composition defined in claim 22 wherein (A) is a mixture of 70% syndiotactic polybutadiene and 30% of cis-IR. ### Claim 24 (depends on 1) The elastomeric composition defined in claim 1 wherein said SBD is from 5 to 20% crystalline. ### Claim 25 (depends on 24) The elastomeric composition defined in claim 24 wherein said cis-IR has a Mooney viscosity at 100.degree. of from 30 to 65. ### Claim 26 (depends on 24) The elastomeric composition defined in claim 24 wherein said mixture of (A) comprises 30 to 70% SBD by weight and correspondingly 70 to 30% cis-IR by weight.