Mitsubishi Rayon Company, Limited

Fumio Suzuki

Teruhiko Sugimori

Hideaki Habara

Haruki Sato

Hiromasa Inada

Yutaro Fukuda

Noriyuki Tajiri

Naoyuki Fukahori

Masaki Sugihara

Wataru Hadano

Toshinori Sumi

Masashi Okamoto

Naoyuki Fukabori

Process for producing thermoplastic copolymer powder

A method for producing a powdery and granular polymer by two coagulation steps comprising coagulating a latex of the polymer, the latex containing a sulfuric acid ester series and/or sulfonic acid series anionic surface active agents, with an acid to an amount of the polymer of 40 to 80 wt. % at a first coagulation step, and then bringing coagulation to completion with an acid or salt at a second coagulation step. According to the present invention, a powdery and granular polymer having a sharp particle size distribution and a high bulk specific gravity can be obtained.

Method for producing powdery and granular polymers

An endoscope comprising as an image-transmitting member a multifilament type plastic optical fiber in which 50 to 20,000 islands having a core-sheath structure, a core diameter of 2 to 70 .mu.m and a circular or substantially circular section are arranged in a zigzag-stacked or square-stacked structure in the sea having a circular or substantially circular section, so that the lamination structure of the entire cores has a substantially circular shape in the section of the image-transmitting portion, wherein the same positional relationship of the ends of light-transmitting paths arranged in the section of the optical fiber is maintained on both the ends of the optical fiber, the periphery of the section of the image-transmitting portion of the optical fiber has a circular or substantially circular shape, and an object lens is attached to one end of the image-transmitting member and an image-transmitting light-receiving member is arranged on the other end of the image-transmitting member.

Multifilament type plastic optical fiber endoscope

The invention discloses a process for the production of a particulate polymer which contains few fine particles and has a narrow particle size distribution and a controlled bulk specific gravity. Characteristic features of the process of this invention reside in that a polymer latex obtained by emulsion polymerization is successively processed through the following steps (I) and (II):

Continuous production process of particulate polymer and control method

Disclosed is method for producing a rubber modified thermoplastic reins which comprises carrying out all or a part of the following setps (I) - (VI):

Method for producing rubber modified thermoplastic resins

Disclosed herein is a particulate polymer prepared by the agglomeration of polymer particles contained in a polymer latex. The particulate polymer is composed of primary particles having particle sizes of at least 20 .mu.m and/or secondary particles formed by the agglomeration of at least some of the primary particles and is in the form of a compact mass substantially free of voids. The particulate polymer is prepared by coagulating the polymer latex in the presence of a coagulant and an organic liquid having low solubility in water. The particulate polymer has a high bulk specific gravity and contains few fine particles. It is thus easy to handle and allows the consumption of energy to be reduced in the drying step.

Particulate polymer and preparation process thereof

Disclosed is a method for producing a rubber modified thermoplastic resin which comprises carrying out all or a part of the following steps (I)-(VI):

An electrostatic recording material comprising a substrate treated for low electric resistance and a dielectric layer formed on the substrate and composed of a composition comprising an insulating resin having a volume specific resistance of at least 10.sup.12 .OMEGA.cm and a powder of an acrylonitrile-type polymer having a copolymerized acrylonitrile content of at least 95% by weight and containing substantially no ionic groups, said powder having a volume average particle size of from 1.5 to 4 .mu.m and a content of particles having a size exceeding 8 .mu.m as measured by a particle size distribution measuring apparatus, being at most 0.02% by number.

Electrostatic recording material

This invention provides a method and an apparatus for controlling a polymerization reaction. The temperature difference between a target temperature, calculated from the degradation rate of a polymerization initiator, which varies as a function of temperature, and a polymerization reactor temperature is calculated. The difference in polymerization rate between a target polymerization rate previously set and a polymerization rate calculated from a measured heat release value at a certain time in the polymerization process is calculated. The temperature inside the reactor is finely adjusted on the basis of the temperature difference and the difference in polymerization rate.

Method and apparatus for controlling polymerization reaction

A screw-type hydro-extracting extruder comprising a raw material supply zone, a hydro-extracting zone and a heat-melting zone, said hydro-extracting zone is comprised of a plurality of doughnut-shaped plates and a slit is formed between every two adjacent plates.

Growing community of inventors

Otake, Japan

Fumio Suzuki