Provided is a polyetherimide-based fiber containing a polyetherimide resin and carbon black dispersed in the resin, wherein the content of the carbon black is 0.03 wt % or greater; the carbon black has a primary particle number-mean particle size of from 30 nm to 500 nm; and the fiber has a weight reduction rate of less than 0.5% around the glass transition point (Tg) of the polyetherimide resin, where the weight reduction rate is defined by a following formula (1).
Weight reduction rate (%)={[(fiber weight at temperature T1)(fiber weight at temperature T2)]/(fiber weight at temperature T1)}100(1) Where T1 denotes a temperature (Tg15 C.) that is 15 C. lower than the glass transition point (glass transition temperature) of the polyetherimide resin, and T2 denotes a temperature (Tg+25 C.) that is 25 C. higher than the glass transition point.

Provided is a polyetherimide-based fiber containing a polyetherimide resin and carbon black dispersed in the resin, wherein the content of the carbon black is 0.03 wt % or greater; the carbon black has a primary particle number-mean particle size of from 30 nm to 500 nm; and the fiber has a weight reduction rate of less than 0.5% around the glass transition point (Tg) of the polyetherimide resin, where the weight reduction rate is defined by a following formula (1).
Weight reduction rate (%)={[(fiber weight at temperature T1)(fiber weight at temperature T2)]/(fiber weight at temperature T1)}100(1) Where T1 denotes a temperature (Tg15 C.) that is 15 C. lower than the glass transition point (glass transition temperature) of the polyetherimide resin, and T2 denotes a temperature (Tg+25 C.) that is 25 C. higher than the glass transition point.

The present invention provides a method for manufacturing a polyacetal fiber in which whiteness irregularity is improved. One embodiment of the present invention provides a method for manufacturing a polyacetal fiber, wherein the method includes a discharge step, a takeup step, a stretching step, and a winding step, the steps being continuously performed, an oxymethylene copolymer being used as the raw material of the polyacetal fiber, the oxymethylene copolymer having an oxymethylene unit and an oxyethylene unit, the content of the oxyethylene unit being 0.5-7.0 moles to 100 moles of the oxymethylene unit, the roller temperature of a stretching unit used in the stretching step being 130-155 C., and operation parameters of the method being set so as to satisfy a prescribed numerical formula.

A cloth containing a fiber having on a surface a polyacetal copolymer containing a prescribed amount of oxyalkylene unit(s), wherein the cloth exhibits a q.sub.max value of at least 0.2 W/cm.sup.2, when the cloth is brought into contact with a heat storing plate of 40 C. under a contact pressure of 0.098 N/cm.sup.2 in an environment at a temperature of 20 C. and at a relative humidity of 65%, is superior in contact cold sensation, colorfastness, quick drying property and gloss.

A method for producing a polyurethane elastic fiber according to the present invention contains the steps of: [1] producing a polyurethane urea polymer (A) having a number average molecular weight ranging from 12,000 to 50,000, and represented by general formula (1); [2] preparing a spinning dope by adding the polyurethane urea polymer (A) to a polyurethane urea polymer (B); and [3] spinning a polyurethane elastic fiber using the spinning dope.

##STR00001##

In the formula, R.sup.1 and R.sup.2 are an alkyl group or a hydroxyalkyl group, R.sup.3 is an alkylene group, a polyethyleneoxy group or a polypropyleneoxy group, R.sup.4 is a diisocyanate residue, X is a urethane bond or a urea bond, R.sup.5 and R.sup.6 are a diisocyanate residue, P is a diol residue, Q is a diamine residue, UT is a urethane bond, UA is a urea bond, each of k, l, m and n is 0 or a positive number.

A method for producing a polyurethane elastic fiber according to the present invention contains the steps of: [1] producing a polyurethane urea polymer (A) having a number average molecular weight ranging from 12,000 to 50,000, and represented by general formula (1); [2] preparing a spinning dope by adding the polyurethane urea polymer (A) to a polyurethane urea polymer (B); and [3] spinning a polyurethane elastic fiber using the spinning dope.

##STR00001##

In the formula, R.sup.1 and R.sup.2 are an alkyl group or a hydroxyalkyl group, R.sup.3 is an alkylene group, a polyethyleneoxy group or a polypropyleneoxy group, R.sup.4 is a diisocyanate residue, X is a urethane bond or a urea bond, R.sup.5 and R.sup.6 are a diisocyanate residue, P is a diol residue, Q is a diamine residue, UT is a urethane bond, UA is a urea bond, each of k, l, m and n is 0 or a positive number.

The invention provides an antimicrobial fiber which exhibits excellent antimicrobial properties even without the addition of antimicrobial agents and can remain antimicrobial even after repeated washing. The antimicrobial fiber comprises a fiber having on a surface thereof a polyacetal copolymer (X) containing oxyalkylene groups, the molar amount of oxyalkylene groups in the polyacetal copolymer (X) being 0.2 to 5 mol % relative to the total of the molar amount of oxymethylene groups and the molar amount of oxyalkylene groups.

The present invention concerns fiber made from a polymer comprising imidazole groups, the polymer further having: i) halide anions being present in an amount in the range of 0.05 to 20.1 weight percent, based on weight of fiber; ii) sulfur, wherein the sulfur is present in the fiber in an amount in the range of 0.05 to 3 weight percent, based on weight of fiber; and iii) alkali metal ion, wherein the alkali metal ion is present in the fiber in an amount in the range of 0.05 to 2 weight percent, based on weight of fiber, the fiber exhibiting hydrochloric acid evolution as identified by TGA-IR between 277.13 C. to 448.19 C.

The present invention concerns fiber made from a polymer comprising imidazole groups, the polymer further having: i) halide anions being present in an amount in the range of 0.05 to 20.1 weight percent, based on weight of fiber; ii) sulfur, wherein the sulfur is present in the fiber in an amount in the range of 0.05 to 3 weight percent, based on weight of fiber; and iii) alkali metal ion, wherein the alkali metal ion is present in the fiber in an amount in the range of 0.05 to 2 weight percent, based on weight of fiber, the fiber exhibiting hydrochloric acid evolution as identified by TGA-IR between 277.13 C. to 448.19 C.

A composition can include a carbon nanofiber, wherein a precursor for the carbon nanofiber includes an alcohol and an aldehyde crosslinked by a primary amine. In certain embodiments, the carbon nanofiber can be biotemplated. Biotemplating enables precise control of morphology at the nanometer scale, while molecular templating allows control of carbon nanotexture and structure at the sub-nanometer scale.