Japan Synthetic Rubber Co., Ltd.

Tanken Seal Seiko Co., Ltd.

Hiroshi Oka

Yoshinori Yoshida

Akira Iio

Noboru Oshima

Takao Miura

Yoichi Kamoshida

Kohei Goto

Noboru Yamahara

Yosihiro Ohira

Chozo Okuda

Zen Komiya

Munenari Kitajima

Yuuzi Naitou

Masayuki Toyoshima

Toshihiko Takahashi

Masao Hisatomi

Masao Sakamoto

The compression ring is mounted on the seal ring at the end thereof. The compression ring has the outer circumference projections that are fixed in the groove extending in the axial direction at the inner surface of the flange . With this construction, the compression ring can move in the axial direction and is stopped in the rotational direction. The compression ring is pressed by the springs Thus the compression ring works as a stopper to stop the rotation of the seal ring and as a spring receiver.

Mechanical seal

A process for producing a hydrogenation product of ring-opening polymer by hydrogenating, in the presence of a hydrogenation catalyst, the non-aromatic carbon-to-carbon double bond present in a ring-opening polymer obtained by subjecting to ring-opening polymerization at least one norbornene derivative represented by general formula (I): ##STR1## wherein A and B independently represent hydrogen atoms or hydrocarbon groups having 1-10 carbon atoms, X and Y independently represent hydrogen atoms, halogen atoms or monovalent organic groups, and m is 0 or 1, alone or in combination with a monomer copolymerizable with said norbronene derivative, characterized by using, as the hydrogenation catalyst, a ruthenium compound represented by general formula (II):

Process for producing hydrogenation product of ring-opening polymer

A transparent resin material consisting of a hydrogenation product of a (co)polymer obtained by subjecting at least one compound represented by general formula (I) or a combination of at least 5% by weight of said compound and 95% by weight or less of other copolymerizable cyclic olefin monomer to metathesis polymerization: ##STR1## wherein A and B are independently hydrogen atoms or C.sub.1-10 hydrocarbon groups; and X and Y are independently hydrogen atoms, C.sub.1-10 hydrocarbon groups, --C(CH.sub.2).sub.n COOR.sup.1 groups or --(CH.sub.2).sub.n OCOR.sup.1 groups [R.sup.1 is a C.sub.1-20 hydrocarbon group and n is 0 or an integer of 1-10] with the proviso that at least one of X and Y is selected from the above --(CH.sub.2).sub.n COOR.sup.1 and --(CH.sub.2).sub.n OCOR.sup.1 groups. Said transparent resin material is moldable and has sufficient optical properties, low hygroscopicity, good heat resistance and excellent adhesion to recording layer.

Transparent resin material

A positive type radiation-sensitive resin composition comprising an alkali-soluble novolac resin and a 1,2-quinonediazide compound, characterized in that said alkali-soluble novolac resin is a resin produced by condensing a carbonyl compound and a phenol mixture comprising 6 to 94 mole % of m-cresol and 94 to 6 mole % of at least one compound represented by the formula (I) other than m-cresol: ##STR1## wherein X is --CH.sub.3, --C.sub.2 H.sub.5, --C(CH.sub.3).sub.3, --CO.sub.2 CH.sub.3 or --CO.sub.2 C.sub.2 H.sub.5 ; n is an integer satisfying 3.gtoreq.m.gtoreq.1; and m is an integer satisfying 3.gtoreq.m.gtoreq.1, in which resin when the polystyrene-reduced molecular weight is determined by a gel permeation chromatography using a monodisperse polystyrene as the standard, maximum values a, b and c present, respectively, in the molecular weight ranges of 6,300 to 25,000, 2,500 to 6,000 and 150 to 900 in the molecular weight distribution curve obtained satisfy the following relationships: a/b=0-1.5 and c/b=1.4-2. Said positive type-radiation-sensitive resin composition is excellent in resolution, sensitivity, developability, thermal resistance and adhesion and hence is useful as a positive type resist for producing integrated circuits having a higher integration.

Positive type radiation-sensitive resin composition comprising a

Polyamide acid obtained by reacting 2,3,5-tricarboxycyclopentane-acetic acid and a diamine in a solvent has a high stability in the form of a solution, has a high workability and is excellent in storage stability. Polyimide obtained by heating said polyamide acid is excellent in heat resistance, mechanical properties, electrical properties and chemical resistance.

Polyamide acid, process for producing same and polyimide obtained

A process for producing a diol by reacting an acetic ester of butanediol or butenediol with methanol, which comprises (a) continuously feeding to a first reaction-distilling column from its upper part a liquid acetic ester of butanediol or butenediol, while continuously feeding methanol to said column from its lower part, to bring both feeds into counter current gas-liquid contact in the presence of an acidic or a basic catalyst, to allow both feeds to react, and withdrawing from the bottom a bottom stream comprising a diol as major constituent, (b) continuously feeding to a hydrolyzer the distillate obtained from said first reaction-distilling column containing methyl acetate as major constituent, thus bringing said distillate into contact with water or steam in the presence of an acidic catalyst to hydrolyze the methyl acetate, (c) then continuously feeding the hydrolysis product thus obtained from the hydrolyzer to a second distilling column, withdrawing a methyl acetate-containing methanol stream from the top of said second distilling column, and recycling said stream to the lower part of the first reaction-distilling column. According to this process, it is possible to leave out the conventional complicated procedure necessary for the separation of methanol and, hence, to save the labor required therefor.

Process for producing diol

A process for producing simultaneously tetrahydrofuran and 1,4-butanediol in any desired proportion which comprises (a) reacting the acetic ester of 1,4-butanediol with a theoretical or smaller quantity, based on said acetic ester, of water (preferably 0.2-0.8 mole of water per mole of said acetic ester) in the presence of an acidic catalyst, (b) distilling, in the first distillation column, the reaction mixture to separate it into a distillate comprising tetrahydrofuran as major constituent and a bottom stream comprising as major constituent the acetic ester of 1,4-butanediol and (c) subjecting, in the second reaction-distillation column, at least a part of said bottom stream to a counter-current gas-liquid contact reaction with methanol, the quantity of said methanol being preferably 1-5 moles per mole of the acetate group of the acetic ester, in the presence of an acidic or basic catalyst and, simultaneously therewith, separating the reaction mixture into a bottom stream comprising 1,4-butanediol as major constituent and a distillate comprising methyl acetate as major constituent. By this process, methanol and catalyst can be economized to a great extent.

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Yokkaichi, Japan

Hiroshi Oka