Sumitomo Riko Company Limited

Ryosuke Yamaoka

Takahiro Morita

Yasunori Nimura

Yasuyuki Hayasaki

Tomohito Seki

Satoshi Tatsumi

Junichiro Suenaga

Risa Tajima

Shigeru Fukagawa

Kousuke Minematsu

This seal member is a cured product of a silicone rubber composition that comprises a silicone rubber and silica particles, and has multiple insertion holes into which counterpart members are inserted; and this seal member satisfies the following conditions (a) to (d). (a) If X (parts by mass) is the content of the silica particles relative to 100 parts by mass of a base polymer of the silicone rubber, (elastic recovery rate (%))/(X (parts by mass)) is from 3.6 to 9.6. (b) The type A durometer hardness is from 15 to 30. (c) The tensile strength at break is 2.1 MPa or more. (d) The coefficient of kinetic friction of the surfaces of the insertion holes is 2.5 or less.

Seal member

Provided is a silicone rubber composition that allows for both the securing of time for filling materials and an improvement in productivity which is achievable due to a short curing time, and that has excellent reproducibility of curing properties. The silicone rubber composition contains (a) an organopolysiloxane having an alkenyl group, (b) a peroxide cross-linking agent, and (c) a heat stabilizer, wherein (c) includes a compound represented by general formula (1). In formula (1), Rrepresents hydrogen or a methyl group, R, R, R, and R, each independently represent a C1-9 alkyl group, and Rrepresents hydrogen or a methyl group.

Silicone rubber composition, silicone rubber crosslinked body, and sealant

Provided are a silicone rubber composition that is excellent in storage stability and crosslinking reactivity, and a silicone rubber crosslinked body made from the silicone rubber composition. The silicone rubber composition contains (a) an organopolysiloxane, (b) a crosslinking agent, and (c) a microcapsule type catalyst that is made of microparticles of a resin and a crosslinking catalyst encapsulated in the microcapsules, wherein the solubility parameter of the resin of (c) is 7.9 or higher, a thermal conductivity of 0.16 W/m&#xb7;K or higher, and a glasstransition temperature of 40 to 145 degrees C. The silicone rubber crosslinked body is made of a crosslinked product of the above-described silicone rubber composition.

Silicone rubber composition and silicone rubber crosslinked body

To provide an elastic roll for an electro-photographic apparatus that includes an elastic body layer having a low hardness and being excellent in fatigue resistance, and thus is resistant to fatigue, and to provide a method for manufacturing the same. An elastic rollfor an electrophotographic apparatus includes a shaft bodyand a foamed elastic body layerprovided on an outer periphery of the shaft bodywherein the foamed elastic body layerconsists of a silicone rubber foamed body including a plurality of air bubblesin its base material containing cross-linked silicone rubber and a reinforcement material, and wherein the foamed elastic body layer has a communication degree of 40% or more. It is preferable that the elastic rollshould further include a skin layerin the foamed elastic body layeron an outer peripheral side.

Growing community of inventors

Komaki, Japan

Ryosuke Yamaoka