Shin-etsu Chemical Co., Ltd.

Mitsui Chemicals, Inc.

Oki Data Corporation

Satao Hirabayashi

Tsutomu Nakamura

Noriyuki Meguriya

Nobumasa Tomizawa

Masaaki Kawasaki

Takeo Yoshida

Yoshiharu Kikuchi

Takashi Hakuta

Hiroshi Kikuchi

Yoshinori Inokuchi

Hidenari Nakahama

Takao Mizutani

Hirokazu Ando

Shigeru Ubukata

Mikio Hosoya

Yuji Ishii

Mitsunao Arino

Taku Koda

Mikio Iino

Shuichi Nonaka

Hiroki Furukawa

Hiroshi Kameda

Masao Matuhira

A method for producing a millable silicone rubber sponge is a method for producing a millable silicone rubber sponge with an open cell ratio of not lower than 20%, comprising:

Millable silicone rubber composition, millable silicone rubber sponge, and method for producing said sponge

A thermal fixing roll or belt-forming silicone rubber composition having a high thermal conductivity, a low compression set, and an improved heat resistance which is well adapted for use as a coating material in a fixing roll or fixing belt is provided. Also provided are a fixing roll and a fixing belt formed by using such composition. The thermal fixing roll or belt-forming silicone rubber composition comprises 100 parts by weight of a heat-curable silicone rubber composition and 50 to 800 parts by weight of silicon carbide having an iron content of up to 0.2% by weight at the surface and an average particle size of 1 to 50 &#x3bc;m.

Silicone rubber composition for highly heat conductive thermal fixing roll or thermal fixing belt, fixing roll, and fixing belt

A thermally conductive silicone rubber sponge composition which is composed of 100 parts by weight of heat-curable organopolysiloxane composition, 0.1 to 50 parts by weight of organic resin hollow filler having an average particle diameter of up to 200 &#x3bc;m and a true specific gravity of up to 0.3, and 20 to 300 parts by weight of thermally conductive filler having an average particle diameter of 1 to 30 &#x3bc;m and a thermal conductivity of at least 15 W/m&#xb7;K, with the highly thermally conductive silicone rubber sponge having voids accounting for 10 to 70% of the entire volume thereof. The silicone rubber sponge composition of the present invention gives a silicone rubber sponge having high thermal conductivity, small heat capacity, low hardness, light weight, and low permanent compression set.

Thermally conductive silicone rubber sponge composition and fixing roll

A heat fixing roll or belt having a silicone rubber layer which is formed by curing a silicone rubber composition comprising (A) 100 pbw of an organopolysiloxane having at least two silicon-bonded alkenyl radicals in a molecule, (B) 20-500 pbw of a metallic silicon powder having an average particle size of up to 100 &#x3bc;m, and (C) an effective amount of a curing agent. The silicone rubber layer has a high heat conductivity and long-term temperature durability.

Heat fixing roll and fixing belt

The crosslinkable rubber composition of the invention is crosslinkable by hot air, and a hot-air crosslinked rubber sheet thereof has no scratch on the surface in a hardness test using a pencil of HB and has a compression set of not more than 70% after a heat treatment at 150&#xb0; C. for 22 hours. The rubber composition comprises an ethylene/&#x3b1;-olefin/non-conjugated polyene random copolymer rubber comprising a specific vinyl end group-containing norbornene compound, a SiH group-containing compound having at least two SiH groups in one molecule, and if necessary, an addition reaction catalyst comprising a platinum group element and a reaction inhibitor.

Crosslinkable rubber compositions and uses thereof

A silicone rubber composition comprising (A) a normally liquid organopolysiloxane having at least two silicon atom-bonded alkenyl radicals, (B) a liquid organohydrogenpolysiloxane having at least two Si&#x2014;H radicals, (C) a blend of two inorganic powders selected from three highly heat conductive inorganic powders which form 30% slurries at pH at least 8, 6 to less than 8, and less than 6, and (D) an addition reaction catalyst cures into a silicone rubber having a high thermal conductivity and heat resistance and is suited for fixing rolls or belts in copiers.

Highly heat conductive silicone rubber composition, fixing roll and fixing belt

The crosslinkable rubber composition of the invention is crosslinkable by hot air, and a hot-air crosslinked rubber sheet thereof has no scratch on the surface in a hardness test using a pencil of HB and has a compression set of not more than 70% after a heat treatment at 150&#xb0; C. for 22 hours. The rubber composition comprises an ethylene/&#x3b1;-olefin/non-conjugated polyene random copolymer rubber comprising a specific vinyl end group-containing norbornene compound, a SiH group-containing compound having at least two SiH groups in one molecule, and if necessary, an addition reaction catalyst comprising a platinum group element and a reaction inhibitor. The automobile weatherstrip, hose, rubber vibration insulator, belt, sealing material, expanded product, covered electric wire, electric wire joint, electric insulating part and household rubber product according to the invention comprise the above-mentioned rubber composition. The rubber composition has a high crosslinking rate and excellent productivity to produce crosslinked rubber molded products, is capable of undergoing hot-air crosslinking such as HAV or UHF and is capable of providing crosslinked rubber molded products having excellent compression set resistance, strength properties, heat resistance, weathering resistance and abrasion resistance.

Crosslinkable rubber compositions and use thereof

Conductive fluorosilicone rubber composition

The invention provides a semiconductive silicone rubber composition comprising (A) an organopolysiloxane containing at least two aliphatic unsaturated groups, (B) reinforcing silica powder having a specific surface area of at least 50 m.sup.2 /g, (C) a conductive agent, (D) a hydrocarbon oil having a heat loss of up to 30% at 200.degree. C./4 hours, and (E) a curing agent. Cured silicone rubber of the composition has a resistance of 1.times.10.sup.3 to 1.times.10.sup.12 .OMEGA. which remains stable for long-term use. The semiconductive silicone rubber composition is appropriate as a semiconductive roll stock for the manufacture of charging rolls, transfer rolls and developing rolls in business machines.

Semiconductive silicone rubber compositions and semiconductive silicone

A silicone rubber roll is characteristically prepared on a metallic center by forming a layer of the cured product of a silicone rubber composition which comprises (A) organopolysiloxane, in which the total amount of low molecular weight siloxanes having a degree of polymerization ranging from 3 to 20 is controlled to be at most 10,000 ppm, (B) reinforcing silica powder with a specific surface area of at least 50 m.sup.2 /g, (C) silicone elastomer particles with an average particle size of 200 .mu.m, in which the total amount of low molecular weight siloxanes having a degree of polymerization ranging from 3 to 20 is 2,000 ppm or less, and (D) a curing agent. The total amount of low molecular weight siloxanes having a degree of polymerization ranging from 3 to 20 within the cured product layer is controlled to be 2,000 ppm or less, since the elimination of the low molecular weight siloxanes having a degree of polymerization ranging from 3 to 20 proceeds effectively during the processes of the silicone rubber composition preparation, forming, and curing. Therefore, the obtained roll is extremely useful for various types of rolls utilized in copying machines which particularly need to avoid the low molecular weight siloxanes.

Silicone rubber roll

An addition curing type silicone rubber composition comprising an aliphatic unsaturated group-containing organopolysiloxane, an organohydrogenpolysiloxane and a platinum series catalyst is further blended with a triazine or sulfide control agent to provide a composition which is stable and resistant against premature gelation at room temperature and thus has long-term storage stability. Heating causes the composition to be quickly vulcanized at an acceptable rate into a silicone rubber having satisfactory physical properties.

Silicone rubber compositions

A rubber compound comprising (A) an organopolysiloxane having at least two alkenyl groups in a molecule and (B) reinforcing silica powder is blended with (C) silicone elastomer particles obtained by reacting an organohydrogenpolysiloxane with a vinyl group-containing organopolysiloxane such that the molar ratio of .tbd.SiH group to --CH.dbd.CH.sub.2 group ranges from 1.2 to 5 and (D) a platinum catalyst to form a silicone rubber composition which cures into a product having high rubber strength despite the inclusion of silicone elastomer particles. The composition finds typical use as silicone rubber parts in copying machines.

Growing community of inventors

Annaka, Japan

Satao Hirabayashi