Abstract: Provided is an organic fiber doubled-and-twisted yarn cord the twist structure of which is uniform and with which it is possible to reduce weight. A doubled-and-twisted yarn cord comprising an organic fiber characterized in that a total fineness is 5000-15000 dtex inclusive, a coefficient of twisted yarn length difference between untwisting yarns constituting the doubled-and-twisted yarn cord that is obtained by an expression: coefficient of twisted yarn length difference (%)=(maximum value of yarn length difference between untwisting yarns)/(average value of yarn length of untwisting yarns)×100 is 1.5% or less, and breaking strength is 7.0 cN/dtex or greater.

Abstract: A method of producing an optical fiber wire including a coating made of an ultraviolet curable resin, the method includes: a first irradiation step including applying first ultraviolet light to a point on the optical fiber wire where at least a portion of the ultraviolet curable resin is uncured; and a second irradiation step including applying second ultraviolet light to the point on the optical fiber wire where at least the portion is cured after the first irradiation step. The portion is a surface layer of the coating. A temperature of the optical fiber wire immediately before the second irradiation step is 50° C. or higher and 300° C. or lower.

Abstract: Provided is an organic fiber doubled-and-twisted yarn cord the twist structure of which is uniform and with which it is possible to reduce weight. A doubled-and-twisted yarn cord comprising an organic fiber characterized in that a total fineness is 5000-15000 dtex inclusive, a coefficient of twisted yarn length difference between untwisting yarns constituting the doubled-and-twisted yarn cord that is obtained by an expression: coefficient of twisted yarn length difference (%)=(maximum value of yarn length difference between untwisting yarns)/(average value of yarn length of untwisting yarns)×100 is 1.5% or less, and breaking strength is 7.0 cN/dtex or greater.

Abstract: Provided is a short rubber reinforcement fiber for short fiber-containing rubber compositions that are used for transmission belts for which friction transmission behavior has been stabilized and travel service life has been further improved. The present invention is a short fiber, which is the product of cutting an adhesive-treated synthetic long fiber multifilament yarn and is used by dispersing in a rubber composition, the short fiber being characterized in that the percentage of the number of non-adhesive-treated single yarns is 0-5%; and a method for manufacturing said short fibers, the method comprising a step for immersing a sudare-woven product in which the synthetic long fiber multifilament yarns have been sudare-woven in an adhesive treatment solution and then pressing at a nip pressure of 1.2-5.0 MPa using nip rolls, and a step for cutting the sudare-woven product bundles obtained to a specified length.

Abstract: Provided is a short rubber reinforcement fiber for short fiber-containing rubber compositions that are used for transmission belts for which friction transmission behavior has been stabilized and travel service life has been further improved. The present invention is a short fiber, which is the product of cutting an adhesive-treated synthetic long fiber multifilament yarn and is used by dispersing in a rubber composition, the short fiber being characterized in that the percentage of the number of non-adhesive-treated single yarns is 0-5%; and a method for manufacturing said short fibers, the method comprising a step for immersing a sudare-woven product in which the synthetic long fiber multifilament yarns have been sudare-woven in an adhesive treatment solution and then pressing at a nip pressure of 1.2-5.0 MPa using nip rolls, and a step for cutting the sudare-woven product bundles obtained to a specified length.