Asahi Kasei Kogyo Kabushiki Kaisha

Kunio Satake

Tsuyoshi Yamada

Kiyoshi Hayakawa

Yasushi Sato

Isaburo Fukawa

Mitsuo Kohno

Katsumi Yoshitake

Noboru Fujikawa

Tadashi Taguchi

Kuniaki Sakamoto

Toshio Ibaragi

Tsutomu Teraoka

Hiroshi Harada

Takeshi Wada

Shunji Kamiya

Tomiho Sone

A novel block copolymer mixture of conjugated diene (C.D.) and vinylaromatic hydrocarbon (V.H.) having a superior transparency and impact-resistance is produced by the following two step polymerizations using an organolithium compound as a catalyst and a solvent consisting mainly of an aliphatic hydrocarbon: a first step (A) of preparing a living (co)polymer of C.D. or C.D. and V.H., by polymerizing the monomer(s) in a ratio by weight of V. H. to C.D. of 0/100 to 60/40 and in an amount of 1 to 80% by weight of total monomers to be used, in the presence of said catalyst and solvent, and a second step (B) of preparing V.H. polymer or block copolymer of V.H. and C.D., by adding to said living (co)polymer, remaining monomer(s), in a ratio by weight of V.H. to C.D. of 100/0 to 65/35 and in an amount of 99 to 20% by weight of total monomers to be used, and said catalyst and solvent, and polymerizing the remaining monomer(s) to obtain a block copolymer mixture, this block copolymer mixture having a ratio of V.H. content of ultimate block copolymers to that of the (co)polymers obtained only in step (B), of at least 1/1.8, and a ratio of V.H. portion to C.D. portion of 60/40 to 95/5.

Block copolymer mixture of conjugated diene and vinyl aromatic

A photopolymerizable element comprising a layer of a photopolymerizable composition and a liquid developer-soluble or -dispersible transparent oriented film support laminated onto one surface of the photopolymerizable composition layer is advantageously employed for the production of a polymeric image without stripping of the film support. The element may further comprise a strippable protective film provided on the other surface of the photopolymerizable composition layer. The element of this invention is useful especially for the production of photoresists which are advantageously used for the manufacture of printed circuit boards.

Photopolymerizable element comprising a soluble or dispersible oriented

A process for producing an image which comprises the steps of: (1) applying to the surface of a substrate the surface of a photosensitive layer, the other surface of the photosensitive layer being adhered to a substantially transparent film support which is soluble or dispersible in a developer consisting essentially of a liquid capable of substantially dissolving or dispersing therein the areas of the layer other than those having a polymeric image produced by imagewise exposure in the step (2) below; (2) exposing the photosensitive layer, imagewise, to actinic radiation to form a polymeric image in the layer; and (3) washing away with the developer the film support and the areas of the layer other than those having the polymeric image to form an image of a polymeric material on the substrate. The photosensitive element having on its one side the above-mentioned specific film support and the process have a variety of applications and are useful for producing photoresists which are advantageously used for making printed circuit boards.

Oriented polystyrene support for photopolymerizable element

Process for producing image using laminated oriented cover film

A novel block copolymer mixture of conjugated diene (C.D.) and vinylaromatic hydrocarbon (V.H.) having a superior transparency and impact-resistance is produced by the following two step polymerizations using an organolithium compound as a catalyst and a solvent consisting mainly of an aliphatic hydrocarbon:

Process for producing mixture of block copolymers

A block copolymer latex composition comprising (A) an aqueous latex containing at least one of block copolymers consisting of conjugated diolefin blocks and monovinyl-substituted aromatic compound blocks prepared by solution-polymerization, and having a molecular weight of 5,000 to 500,000 and a content of monovinyl-substituted aromatic compound of 10 to 70% by weight, and (B) a latex of rubber system, latex of synthetic resin system or a mixture thereof, the composition containing 5 to 87% by weight of (A) and 95 to 13% by weight of (B) in terms of solid matters, has very superior film-forming properties and provides films having improved strength.

Block copolymer latex composition

High-impact polystyrene composition is produced by radical polymerization, e.g. bulk or bulk-suspension polymerization, of styrene having dissolved therein 2 to 20% by weight of one or more polybutadienes prepared by solution polymerization using an organic lithium compound as catalyst, said polybutadienes having (1) 1,2-vinyl content of more than 15 to 35% and cis-1,4 content of 20 to 85%, and (2) Mooney viscosity of 25 to 85, 5% styrene solution viscosity at 25.degree. C. being 50 to 200 cps and between 1.5 and 3.0 of the Mooney viscosity.

High-impact polystyrene composition and production thereof

This invention provides a concentrated latex of synthetic rubbers almost without causing precipitation or coagulation of the latex components.

Concentrated latex of synthetic rubbers and the method for the

A novel high-impact polystyrene composition superior to conventional high-impact polystyrene composition, in low temperature high-impact properties, tensile strength, processability, toughness, stiffness, etc. can be obtained by a radical polymerization of a mixture of (1) 2-20% by weight of a random copolymer having a composition of continuously and gradually reduced styrene content along the polymer chain of the copolymer which is obtained by the solution polymerization of butadiene and styrene in the presence of a lithium base catalyst and (2) 80-98% by weight of styrene, carried out in bulk polymerization manner or in a manner in which bulk and suspension polymerizations are used in series.

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Yokohama, Japan

Kunio Satake