Teijin Limited

Akebono Brake Industry Co., Ltd.

Teijin Limied

Keizo Shimada

Akihiro Aoki

Hiroshi Mera

Toshiaki Harada

Tsutomu Nakamura

Hideharu Sasaki

Toru Sawaki

Masahiro Koga

Yorikazu Tamura

Shizuo Nagahama

Yuzo Aito

Hidetsugu Yoshida

Koji Sumitani

Noriaki Sasaki

Seiji Itoh

Yasuo Nakagawa

Akio Nakaishi

Takashi Watanabe

Toshihiro Aoyama

Takeo Nishikawa

Yutaka Tabe

Kazuhiro Sato

Hiroyoshi Minematsu

Jiro Sadanobu

Kimihiko Sato

Hiromitsu Takamoto

Risuke Suzuki

Akio Namatame

Osamu Kai

Tsugusi Yosida

Yasusaburo Sugita

Tsugushi Yoshida

A polyamide comprising a solution of (i) an aliphatic polyamide and/or an aliphatic aromatic poly amide dissolved in (ii) N-methyl-2-pyrrolidone and containing (iii) calcium chloride, the ratio between the polyamide (i) and the N-methyl-2-pyrrolidone (ii) in the solution composition being 3 to 25% by weight of the polyamide (i)to 97 to 75% by weight of the N-methyl-2-pyrrolidone, (ii) with the solution also containing calcium chloride (iii) in an amount of 5 to 60 parts by weight based on 100 parts by weight of the polyamide (i) which can be precipitated in a precipitant consisting essentially of water while stirring the precipitant to provide fibrids, which then can be mixed with fibers or natural pulp and formed into synthetic paper.

Polyamide solution composition and methods for producing fibrids and

Method for preparing dialkylnaphthalene

In a process for producing an alkenylbenzene by the reaction of an alkylbenzene having 8 or more carbon atoms and a conjugated diolefin, the improvement in which the reaction is performed in the presence of a catalyst obtained by dispersing (a) an alkali metal and (b) potassium carbonate and/or potassium hydroxide in the presence of (c) an aromatic hydrocarbon having at least a substituent with a double bond.

Process for producing alkenylbenzene

A shaped silicon carbide-based ceramic article having an improved mechanical strength is produced at a high efficiency by a process comprising the step of: forming an organic silicone polymer, for example, polycarbosilastyrene copolymer, into a predetermined shape, for example, a filament or film; doping the shaped polymer with a doping material consisting of at least one type of halogen, for example, bromine or iodine, in an amount of 0.01% to 150% based on the weight of the shaped polymer, to render the shaped polymer infusible; and pyrolyzing the infusible shaped polymer into a shaped SiC-based ceramic article at a temperature of 800.degree. C. to 1400.degree. C. in an inert gas atmosphere, optionally the halogen-doped shaped polymer being treated with a basic material, for example, ammonia, before the pyrolyzing step, to make the filament uniformly infusible.

Shaped silion carbide-eased ceramic article

A shaped silicon carbide-based ceramic article having an improved mechanical strength is produced at a high efficiency by a process comprising the step of: forming an organic silicon polymer, for example, polycarbosilastyrene copolymer, into a predetermined shape, for example, a filament or film; doping the shaped polymer with a doping material consisting of at least one type of halogen, for example, bromine or iodine, in an amount of 0.01% to 150% based on the weight of the shaped polymer, to render the shaped polymer infusible; and pyrolyzing the infusible shaped polymer into a shaped SiC-based ceramic article at a temperature of 800.degree. C. to 1400.degree. C. in an inert gas atmosphere, optionally the halogen-doped shaped polymer being treated with a basic material, for example, ammonia, before the pyrolyzing step, to make the filament uniformly infusible.

Process for producing a shaped silicon carbide-based ceramic article

A new polycarbosilastyrene copolymer which comprises recurring carbosilane units of the formula I: ##STR1## and recurring silastyrene units of the formula II: ##STR2## and having easy shaping and sintering properties, is produced by ultra-violet ray treatment and/or heat treatment of a polysilastyrene material and is useful for producing a shaped sintered silicon carbide article by shaping the polycarbosilastyrene copolymer to a desired form, by applying an ultra-violet ray treatment or heat treatment to the shaped article, and by sintering the resultant corss-linked, non-fusible shaped article at an elevated temperature.

Polycarbosilastyrene copolymer, method for producing the same, and

A polycarbosilastyrene copolymer which comprises recurring carbosilane units of the formula I: ##STR1## and recurring silastyrene units of the formula II: ##STR2## is useful for producing a shaped sintered silicon carbide article by shaping the polycarbosilastyrene copolymer to a desired form, by applying an ultra-violet ray treatment or heat treatment to the shaped article, and by sintering the resultant cross-linked, non-fusible shaped article at an elevated temperature.

Process for producing shaped silicon carbide article from a

A fiber-reinforced composite material comprising a resin and 20 to 90% by weight, based on the composite material, of reinforcing fibers, said reinforcing fibers comprising fibers of a wholly aromatic polyamide consisting essentially of

Fiber-reinforced composite materials

There is provided an aromatic polyamide composition, which comprises (a) a polyamide, the recurring structural units of which are substantially totally aromatic, (b) an organic amide solvent, and (c) one or more salts selected from chlorides and bromides of an alkali metal, an alkaline earth metal or ammonium. The amounts of the polyamide and the organic amide solvent are in the ranges of 30 to 50% and 70 to 50% by weight, respectively, based on the total weight of the polyamide and the organic amide solvent. The amount of the salt is defined by the formulae:

Aromatic polyamide composition and processes for preparing film and

High modulus shaped articles such as fibers and films, composed of a wholly aromatic copolyamide, are provided. The wholly aromatic copolyamide is comprised of recurring units of the formulae:

Wholly aromatic halogenated polyamide fiber and film

An aromatic polyamide paper-like sheet having excellent heat- and chemical- resistances and electric insulating properties, comprises an artificial pulp ingredient comprising a number of amorphous pulp particles consisting of an aromatic polyamide material, and a fiber ingredient consisting of a number of short fibers bonded to each other with the amorphous pulp particles, the ratio in weight of the artificial pulp ingredient to the fiber ingredient being in a range of from 1:9 to 9:1 and the aromatic polyamide molecules contained at least in the amorphous pulp particles being cross-linked with a cross-linking agent.

Aromatic polyamide paper-like sheet and processes for producing the same

A wholly aromatic polyamide fiber non-woven sheet having satisfactory density, impregnating property, heat resistance, and surface evenness, comprises mutually, randomly entangled fibers consisting essentially of a wholly aromatic polyamide having 85 molar % or more of at least one type of recurring units selected from those of the formulae (I) and (II): ##STR1## The non-woven sheet is characterized in that the wholly aromatic polyamide fibers have portions thereof having a flattened cross-sectional profile; the aromatic polyamide fibers are fuse-bonded to each other at least at portions thereof intersecting each other; and the sheet includes pores connected to each other, and having a size at the peak of pore size distribution, of 13 microns or less determined by means of a mercury porosimeter, and no voids isolated from each other, and has a porosity of from 5% to 40% and an air permeability rate of from 0.1 to 10,000 sec/100 ml.

Wholly aromatic polyamide fiber non-woven sheet and processes for

An aromatic copolyamide comprising recurring units (A) of the formula (I), (B) of the formula (II) and (C) of the formula (III): ##STR1## wherein in (I), (II) and (III), Ar.sub.1 is phenylene, naphthylene or biphenylene radicals, each having two valence bonds oriented meta; Ar.sub.2 is phenylene, naphthylene or biphenylene radicals, each having two valence bonds oriented coaxially or in parallel to each other and radicals of the formula (IV): ##STR2## wherein Y.sub.1 and Y.sub.2 are independently ##STR3## and; X.sub.1, X.sub.2, X.sub.3, X.sub.4, X.sub.5 and X.sub.6 respectively are independently --NH-- and --CO-- radicals, connected to each other to form an amide bond (--NHCO-- or --CHNH--), and the molar proportions of said recurring units (A), (B), and (C) fall within a quadrilateral defined by the co-ordinates P, Q, R and S or on a twice-turned line defined by the co-ordinates Q, R, S and P:

Aromatic copolyamide containing 3,4'-diphenylene moiety

A papery product consisting essentially of a fibrous web, at least part of said web being made of a wholly aromatic polyamide fiber having a readily soluble skin layer and a sparingly soluble or insoluble core layer, and pressure and heat being applied to said web. Said product is excellent in its mechanical and heat-resisting properties.

Papery product

An aromatic and/or heterocyclic polyamide-amide type polar solvent composition is prepared by prepolymerizing an aromatic or heterocyclic diamine with an aromatic or heterocyclic or heterocyclic dicarboxylic acid chloride in a smaller molar equivalent than that of the diamine to prepare a prepolymer solution having a solution viscosity of 20 poise or less; by removing a by-product, hydrochloric acid, from the resultant prepolymer solution by neutralizing it with ammonia to such an extent that the pH of a mixture of 10 g of the neutralized mixture with 200 ml of water becomes 3.7 to 8.0; by high polymerizing the prepolymer with an additional amount of aromatic or heterocyclic dicarboxylic acid chloride, and; finally, by converting the entire amount of hydrochloric acid and 10 to 70% NH.sub.4 Cl in the resultant polyamide solution into an amide type polar solvent-soluble salt, with a neutralizing agent, the amount of the salt being in a range of from 5 to 95% by weight of the theoretical amount of the salt to be derived from the entire amount of the dicarboxylic acid chloride.

Growing community of inventors

Iwakuni, Japan

Keizo Shimada