Abstract: A flame resistant polymer is obtained by reacting polyacrylonitrile with amine and nitro compounds, the polyacrylonitrile being polymerized by aqueous suspension polymerization using a redox initiator and containing an S component at an amount of 3,000 ?g/g or less. A PAN-based polymer in which both yarn producing properties and flame resistance are improved can be realized.

Abstract: A polyacrylonitrile (PAN)-based carbon fiber includes three or more phases different in crystal size.

Abstract: A flame resistant polymer is obtained by reacting polyacrylonitrile with amine and nitro compounds, the polyacrylonitrile being polymerized by aqueous suspension polymerization using a redox initiator and containing an S component at an amount of 3,000 ?g/g or less. A PAN-based polymer in which both yarn producing properties and flame resistance are improved can be realized.

Abstract: A flame-resistant polymer excels in moldability capable of providing a flame-resistant molded item of novel configuration; a relevant flame-resistant polymer solution; a process for easily producing them; a carbon molding from the flame-resistant polymer; and a process for easily producing the same. A flame-resistant polymer is modified with an amine compound. Further, a flame-resistant polymer solution has the polymer dissolved in a polar organic solvent. A flame-resistant molding whose part or entirety is constituted of the flame-resistant polymer modified with an amine compound. A carbon molding was part or entirety constituted of a carbon component resulting from carbonization of the flame-resistant polymer modified with an amine compound. From the solution containing the flame-resistant polymer, moldings of various configurations can be obtained through further work.

Abstract: In a flame resistant fiber assembly obtainable by fiber forming a flame resistant polymer, a flame resistant fiber of a higher performance is obtained by improving fiber forming ability. A carbon fiber of a high performance is obtained by carbonizing the flame resistant fiber. At obtaining a flame resistant fiber by subjecting a solution containing a flame resistant polymer modified by an amine-based compound to a wet spinning or a semi-dry spinning in a coagulation bath in such a way that a degree of swelling of a coagulated yarn at the outlet of the coagulation bath is 100 to 1000 wt % and then, in a bath, subjecting to a drawing and/or water washing and to a drying under tension, the flame resistant fiber is produced by controlling temperature of the drawing bath/water washing bath, drying temperature or tension in such a way that the obtained fiber would not crystallize. A carbon fiber is produced by carbonizing the flame resistant fiber.

Abstract: A flame-resistant polymer excels in moldability capable of providing a flame-resistant molded item of novel configuration; a relevant flame-resistant polymer solution; a process for easily producing them; a carbon molding from the flame-resistant polymer; and a process for easily producing the same. A flame-resistant polymer is modified with an amine compound. Further, a flame-resistant polymer solution has the polymer dissolved in a polar organic solvent. A flame-resistant molding whose part or entirety is constituted of the flame-resistant polymer modified with an amine compound. A carbon molding was part or entirety constituted of a carbon component resulting from carbonization of the flame-resistant polymer modified with an amine compound. From the solution containing the flame-resistant polymer, moldings of various configurations can be obtained through further work.

Abstract: A flame-resistant polymer excelling in moldability capable of providing a flame-resistant molded item of novel configuration; a relevant flame-resistant polymer solution; a process for easily producing them; a carbon molding from the flame-resistant polymer; and a process for easily producing the same. There is provided a flame-resistant polymer modified with an amine compound. Further, there is provided a flame-resistant polymer solution in which the polymer is dissolved in a polar organic solvent. Still further, there is provided a flame-resistant molding whose part or entirety is constituted of the flame-resistant polymer modified with an amine compound. Moreover, there is provided a carbon molding whose part or entirety is constituted of a carbon component resulting from carbonization of the flame-resistant polymer modified with an amine compound. Still further, there is provided a process for producing them.

Abstract: In a flame resistant fiber assembly obtainable by fiber forming a flame resistant polymer, a flame resistant fiber of a higher performance is obtained by improving fiber forming ability. A carbon fiber of a high performance is obtained by carbonizing the flame resistant fiber. At obtaining a flame resistant fiber by subjecting a solution containing a flame resistant polymer modified by an amine-based compound to a wet spinning or a semi-dry spinning in a coagulation bath in such a way that a degree of swelling of a coagulated yarn at the outlet of the coagulation bath is 100 to 1000 wt % and then, in a bath, subjecting to a drawing and/or water washing and to a drying under tension, the flame resistant fiber is produced by controlling temperature of the drawing bath/water washing bath, drying temperature or tension in such a way that the obtained fiber would not crystallize. A carbon fiber is produced by carbonizing the flame resistant fiber.

Abstract: A flame-resistant polymer excelling in moldability capable of providing a flame-resistant molded item of novel configuration; a relevant flame-resistant polymer solution; a process for easily producing them; a carbon molding from the flame-resistant polymer; and a process for easily producing the same. There is provided a flame-resistant polymer modified with an amine compound. Further, there is provided a flame-resistant polymer solution in which the polymer is dissolved in a polar organic solvent. Still further, there is provided a flame-resistant molding whose part or entirety is constituted of the flame-resistant polymer modified with an amine compound. Moreover, there is provided a carbon molding whose part or entirety is constituted of a carbon component resulting from carbonization of the flame-resistant polymer modified with an amine compound. Still further, there is provided a process for producing them.

Abstract: A material and product excellent in stability in the yarn forming process, small in the color shade contrast due to dyeing, to provide natural irregularity, having microscopic unevenness on the surface of a fabric, to provide dry touch to the eyes and by touch, and good in color fastness are disclosed.The polyamide based fibers of the present invention is a thick and thin yarn in which the unevenness of thickness in the length direction of the polyamide based multifilament is 5 to 20% and in which the standard deviation of the stress at 40% elongation in the stress-strain curve with a sample length of 20 cm is 0.3 g/d or less. The thick and thin yarn can be produced by a process, in which an undrawn polyamide based multifilament of 20.times.10.sup.-3 or less in birefringence .DELTA.n is drawn at a low ratio, comprising the steps of falsely twisting it at a position between a feed roller and a draw roller, drawing from 1.5 to 2.5 times, and thermosetting at 100.degree. C. to 200.degree. C.

Abstract: The present specification discloses a hygroscopic polyester copolymer with a hydrophilic compound copolymerized, containing a cross-linking agent and controlled in moisture absorbing and releasing property, and a fiber using the polyester copolymer. The fiber can be used as a comfortable material for underwear, sports wear, interlinings, etc. as highly hygroscopic woven and knitted fabrics, etc. of high quality.