Jfe Chemical Corporation

Ube Industries, Inc.

Taiheiyo Cement Corporation

Yamato Scientific Co., Ltd.

Adchemco Corporation

Hiroaki Mori

Katsuhiko Tada

Tetsuo Hachiya

Naoyuki Kitamura

Risa Nakayama

Takeshi Orii

Takahiko Sado

Youko Sugio

Shinpei Maehori

Shingo Sugiyama

Katsuya Kono

Youhei Inoue

Yukio Suzuki

Naoki Kumagai

Tatsuhiko Saito

Shigeki Inatomi

Tamotsu Konishi

Hikaru Takabatake

Masahiro Ida

A polyamide acid composition and a polyimide composition are obtained from a tetracarboxylic acid compound containing an aromatic tetracarboxylic acid compound having a naphthalene skeleton and a diamine compound containing an aromatic diamine compound having a biphenyl skeleton.

Polyamide acid composition and polyimide composition

Provided is a cement composition that has high fluidity (for example, a 0-drop flow value of 200 mm or more) before curing and exhibits high compressive strength (for example, 320 N/mmor more) after curing. The cement composition includes a cement, a silica fume having a BET specific surface area of from 10 m/g to 25 m/g, an inorganic powder having a 50% cumulative particle size of from 0.8 &#x3bc;m to 5 &#x3bc;m, a fine aggregate having a maximum particle size of 1.2 mm or less, a water reducing agent, an antifoaming agent, and water. The ratio of the cement is from 55 vol % to 65 vol %, the ratio of the silica fume is from 5 vol % to 25 vol %, and the ratio of the inorganic powder is from 15 vol % to 35 vol % in the total amount of 100 vol % of the cement, the silica fume, and the inorganic powder.

Cement composition and manufacturing method for cement cured body using same

There is provided a polyimide composition that is useful for electronic substrate materials, retains high heat resistance and mechanical strength intrinsic to polyimides, and has a lower dielectric constant and dielectric loss tangent. A polyimide composition for use in electronic substrate materials, containing a polyimide produced by polymerization between a diamine component containing 5-(4-aminophenoxy)-3-[4-(4-aminophenoxy)phenyl]-1,1,3-trimethylindan and an acid component containing 3,3',4,4&#x2032;-biphenyltetracarboxylic acid dianhydride.

Poly(amic acid) composition and polyimide composition

A process is provided for the production of 2,7-dibromofluorenone. According to the process, a 2,7-dibromofluorene-contianing raw material is oxidized with molecular oxygen in the presence of a phase transfer catalyst such as a quaternary ammonium salt in a heterogeneous, mixed solvent of an aqueous solution of a caustic alkali and a water-insoluble organic solvent. Crude crystals of 2,7-dibromofluorenone, which have been obtained by the oxidization, can be purified by recrystallization to recover 2,7-dibromofluorenone as crystals having a purity of at least 99 wt. %.

Production process of 2,7-dibromofluorenone

A method for preparing bromofluorenes includes a step of dispersing a compound selected from the group consisting of fluorene, fluorenone, and derivatives of fluorene and fluorenone in water to prepare a disperse system. Bromination is initiated by adding bromine Brinto the disperse system. Thus, bromofluorenes can be efficiently and economically prepared without using any environmentally harmful organic solvent requiring a high cost to dispose of.

Method for preparing bromofluorenes

Indene is produced from an indene-containing coal tar distillate by adding a glycol to the indene-containing coal tar distillate and then conducting azeotropic distillation to obtain an indene fraction while eliminating benzonitrile from the indene-containing coal tar distillate.

Production process of indene

A process is provided for the purification of 4,4&prime;-(9-fluorenylidene)diallylphenol. With an inclusion-compound-forming solvent which contains an inclusion-compound-forming compound capable of forming an inclusion compound with 4,4&prime;-(9-fluorenylidene)diallylphenol, crude 4,4&prime;-(9-fluorenylidene)diallylphenol is dissolved to form the inclusion compound in the form of a solution. The inclusion compound is then caused to deposit, for example, by charging the solution of the inclusion compound into a poor solvent for the inclusion compound, for example, an aliphatic hydrocarbon solvent such as n-hexane, n-heptane, cyclohexane or a mixture thereof.

Purification process of fluorenylidenediallylphenol

Preparation process of fluorenes

A spray dryer device for spray drying a sample dissolved in an organic solvent is disclosed, comprising a circulation line in which an inert gas is circulated by a blower, a heater for heating the inert gas to a specified temperature, a main drying chamber provided with a spray nozzle through which the sample dissolved in the organic solvent is sprayed into the inert gas, a collector in which the powdered sample produced in the main drying chamber is collected, and a condenser in which the gaseous organic solvent is condensed and recovered. The powdered sample is obtained in this spray dryer device for spray drying organic solvents by spraying the organic solvent through the spray nozzle into the main drying chamber in which the oxygen concentration is held to a low value by the introduction of the inert gas.

Organic solvent spray dryer device

A three-dimensionally shaped aromatic imide polymer sheet article is produced by a method comprising the steps of shaping an aromatic imide polymer sheet having a second order transition temperature of 250.degree. C. to 400.degree. C. and an ultimate elongation of 120% or more at 100.degree. C., by press-stretching at least a portion of the sheet at a temperature of 100.degree. C. or more, but not exceeding a temperature of 100.degree. C. higher than the second order transition temperature of the sheet, into a desired three-dimensional convex or concave form protruding from the sheet, heat-setting the resultant shaped sheet article in its shaped form at a temperature equal to or higher than the second order transition temperature of the sheet, and then cooling the heat-set sheet article to a desired low temperature.

Method for producing a three-dimensionally shaped aromatic imide polymer

There is provided a continuous flow type homogenizer. The homogenizer comprises, a tubular container having at upper end thereof an inlet for introducing tissue to be homogenized and at lower end thereof an outlet for discharging the homogenized tissue, a pestle disposed freely rotatable in the tubular container with a clearance defined between the inner surface of the tubular container and the peripheral surface of the pestle, a rotation shaft driving means connected to a rotation shaft of the pestle, a speed setting means for setting the rotation speed of the pestle, and a speed controlling means for controlling the speed of the rotation shaft with a predetermined speed gradient with respect to a speed value set by the speed setting means. '

Continuous flow type homogenizer

An aromatic polyimide laminate sheet having a relatively large thickness of 50 .mu.m or more comprises (1) at least one first film layer comprising a polymerization-imidization product of an acid component containing 80 to 100 molar % of at least one biphenyltetracarboxylic acid with an amine component containing 80 to 100 molar % of at least one aromatic diamine having two or more benzene rings, and having a glass transition point of 250.degree. C. to 350.degree. C.; and (2) at least one second film layer comprising an aromatic imide polymer, the first and second film layers being alternately laminated on and directly bonded to each other without using bonding material.

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Tokyo, Japan

Hiroaki Mori