Abstract: A fluororubber composition comprising 5 to 30 parts by weight of carbon black having an iodine adsorption of 70 mg/g or more, 5 to 20 parts by weight of carbon fiber having an average fiber diameter of 5 to 20 ?m and an aspect ratio of 2 to 10, and 3 to 20 parts by weight of PTFE, based on 100 parts by weight of fluororubber. The crosslinked molded article obtained from the fluororubber composition exhibits excellent effects of imparting oil film retention by using carbon fiber with specific properties, and improving abrasion resistance in unlubricated conditions by using the carbon fiber in combination with PTFE as a solid lubricant.

Abstract: A seal ring is an annular seal ring which is configured to be interposed between first and second members, and seals a gap between the first and second members. The second member is inserted into the first member, and reciprocates in its axial direction with respect to the first member. The seal ring includes an annular base part, an annular innermost end part, and a widening protrusion part. The annular base part has a radially exterior end to contact the first member. The annular innermost end part is integrally formed with a radially interior end of the base part to contact the second member. The widening protrusion part is integrally formed with the innermost end part, and protrudes with respect to the base part in the axial direction of the second member.

Abstract: A fluororubber composition comprising 3 to 20 parts by weight of carbon fibers and 1 to 8 parts by weight of carbon nanotubes based on 100 parts by weight of fluororubber. The crosslinked molded article obtained from the fluororubber composition has excellent effects of not only imparting oil film retention, but also improving the material strength of fluororubber due to the combined use of carbon nanotubes, which have high reinforcing properties. Further, the fluororubber composition can give a fluororubber crosslinked product excellent in abrasion resistance and pressure resistance.

Abstract: A sealing device which can reduce its sliding friction is provided. A sealing device is configured to be attached into an annular attachment groove which is opened radially outward, and includes a first ring and a second ring. The first ring is formed of a rubber-like elastic material. The first ring includes an inner peripheral contact surface, an outer peripheral contact surface a cut portion, and an annular holding groove. The inner peripheral contact surface is configured to contact a bottom surface of the attachment groove. The outer peripheral contact surface is configured to be positioned on a side opposite to the attachment groove. The cut portion is arranged in a part of the circumference of the first ring. The annular holding groove is opened in an end surface of the first ring on a pressure side. The second ring is formed of a rubber-like elastic material and held in the holding groove.

Abstract: A seal ring is an annular seal ring which is configured to be interposed between first and second members, and seals a gap between the first and second members. The second member is inserted into the first member, and reciprocates in its axial direction with respect to the first member. The seal ring includes an annular base part, an annular innermost end part, and a widening protrusion part. The annular base part has a radially exterior end to contact the first member. The annular innermost end part is integrally formed with a radially interior end of the base part to contact the second member. The widening protrusion part is integrally formed with the innermost end part, and protrudes with respect to the base part in the axial direction of the second member.

Abstract: A natural yeast extract which is rich in glutamic acid and therefore has an impact at first taste. Further, provided is a yeast extract which is also rich in 5?-guanylic acid or 5?-inosinic acid and therefore has strong umami. Further, provided is a yeast mutant capable of accumulating a large amount of glutamic acid, glutamine and ribonucleic acid for obtaining such a yeast extract. A yeast mutant to which resistance to organic acids and analogues thereof has been imparted by inducing spontaneous mutation, accumulates a significant amount, i.e., 10% by weight or more of the total of free glutamic acid and glutamine in the cell, and further accumulates 5% by weight or more of a ribonucleic acid. The yeast extract produced by using this strain contains 20% by weight or more of L-glutamic acid, and further contains 3% by weight or more of 5?-IG.

Abstract: A natural yeast extract which is rich in glutamic acid and therefore has an impact at first taste. Further, provided is a yeast extract which is also rich in 5?-guanylic acid or 5?-inosinic acid and therefore has strong umami. Further, provided is a yeast mutant capable of accumulating a large amount of glutamic acid, glutamine and ribonucleic acid for obtaining such a yeast extract. A yeast mutant to which resistance to organic acids and analogues thereof has been imparted by inducing spontaneous mutation, accumulates a significant amount, i.e., 10% by weight or more of the total of free glutamic acid and glutamine in the cell, and further accumulates 5% by weight or more of a ribonucleic acid. The yeast extract produced by using this strain contains 20% by weight or more of L-glutamic acid, and further contains 3% by weight or more of 5?-IG.

Abstract: The present invention provides a natural yeast extract having a high-impact first taste by containing glutamic acid in a large amount. Further, the present invention provides a yeast extract having strong umami by containing 5?-guanylic acid or 5?-inosinic acid in a large amount. In addition, the present invention provides a yeast mutant accumulating glutamic acid, glutamine, and ribonucleic acid in a large amount for obtaining the yeast extract. A yeast mutant inducing a natural mutation to which organic acid-tolerance or organic acid analogue-tolerance is imparted accumulates free glutamic acid and glutamine in such a significant amount as a total amount of 10% by weight or more in a cell, and further accumulates ribonucleic acid in an amount of 5% by weight or more. A yeast extract produced using the above yeast mutant contains L-glutamic acid in an amount of 20% by weight or more, and further contains 5?-IG in an amount of 3% by weight or more.

Abstract: A natural yeast extract which is rich in glutamic acid and therefore has an impact at first taste. Further, provided is a yeast extract which is also rich in 5?-guanylic acid or 5?-inosinic acid and therefore has strong umami. Further, provided is a yeast mutant capable of accumulating a large amount of glutamic acid, glutamine and ribonucleic acid for obtaining such a yeast extract. A yeast mutant to which resistance to organic acids and analogues thereof has been imparted by inducing spontaneous mutation, accumulates a significant amount, i.e., 10% by weight or more of the total of free glutamic acid and glutamine in the cell, and further accumulates 5% by weight or more of a ribonucleic acid. The yeast extract produced by using this strain contains 20% by weight or more of L-glutamic acid, and further contains 3% by weight or more of 5?-IG.