Teijin Limited

Kohichi Iohara

Michikage Matsui

Togi Suzuki

Shinji Ohwaki

Setsuo Yamada

Osamu Wada

Akio Kimura

Tadashi Konishi

Hironori Yamada

Kimihiro Ogawa

An improved copolyester fiber capable of being dyed with cationic dyes and having an excellent brightness, heat resistance and a satisfactory mechanical strength comprises a copolyester resin comprising a polymerization product of at least one aromatic dicarboxylic acid compound, at least one alkylene diol compound and at least one quaternary phosphonium organic sulfonate of the formula (I): ##STR1## wherein A=an aromatic or aliphatic radical, X.sup.1 =H or an ester-forming organic radical, X.sup.2 =an ester-forming organic radical, R.sup.1, R.sup.2, R.sup.3 and R.sup.4 =an alkyl or aryl radical, n=1 or more, and having an [.eta.].sub.f of 0.5 or more, the copolyester fiber having a silk factor of 25 or more and exhibiting the number of scission of backbone chains of the copolyester molecules of 140.times.10.sup.23 or less per 10.sup.6 g of fiber when wet heat-treated in a solution of 0.4 g/l of acetic acid in distilled water at 130.degree. for 60 minutes.

Cationically-dyeable, thermally-resistant copolyester fiber comprising

A fiber composed of a polyester having at least a part of terminals blocked with the residue of at least one specific metal sulfonate compound, where the amount of the blocked terminals is 1.3 to 4.0 mol % based on the dicarboxylic acid component of the polyester and the alkali dissolution speed constant is 3.3.times.10.sup.-9 to 6.5.times.10.sup.-9 cm/sec. This polyester has a good dyeability with a cationic dye and is excellent in the heat resistance and alkali resistance. The polyester fiber can be spun at a high speed or super high speed and can be false-twisted at a high temperature.

Modified polyester fiber and process for preparation thereof

An undrawn polyester yarn comprising 0.2 to 10% by weight of a polymer having a recurring unit structure represented by the following formula (1): ##STR1## wherein R.sub.1 and R.sub.2 stand for substituents consisting of optional atoms selected from C, H, N, O, S, P and halogen atoms, with the proviso that the sum of the molecular weights of R.sub.1 and R.sub.2 is equal to or more than 40, and n is a positive integer, and having a molecular weight equal to or more than 1000, the elongation increase ratio (I) of the undrawn polyester yarn, represented by the following formula (2), being equal to or more than 8%: ##EQU1## wherein EL.sub.b stands for the residual elongation (%) of the undrawn yarn and EL.sub.o stands for the residual elongation (%) of a corresponding undrawn polyester yarn substantially free of the polymer represented by the formula (1).

Undrawn polyester yarn and process for manufacturing

A high twist polyester multifilament yarn having a twist of a twist multiplier K within a range between 15,000 and 25,000, made from polyester filaments consisting essentially of a copolymer of two or more monomers selected from the group consisting of ethylene terephthalate, trimethylene terephthalate and tetramethylene terephthalate and/or a blend of two or more polymers of the respective monomers and having a breaking elongation of not more than 60% and a shrinkage in boiling water of not more than 6%. A woven or knitted crepe fabric obtained by employing such a high twist yarn has a desirable pebble configuration.

High twist polyester multifilament yarn and fabric made therefrom

A polyester multifilament consisting essentially of a filament groups (I) and (II). The filament group (I) is composed of a polyester selected from the group consisting of polyethylene terephthalate, polytrimethylene terephthalate and polytetramethylene terephthalate, and/or a blend and/or copolymer comprising at least two members selected from the polyesters. The filament group (II) is composed of a substrate composed of a polyester selected from the group consisting of polyethylene terephthalate, polytrimethylene terephthalate and polytetramethylene terephthalate, and/or a blend and/or a copolymer comprising at least two members selected from the polyesters and at least one polymer selected from the group consisting of styrene type polymers, methacrylate type polymers and acrylate type polymers, which is added to said substrate in an amount of 0.4 to 8% by weight based on the substrate.

Polyester multifilament yarn and a process for manufacturing the same

A polyester multifilament consisting essentially of filament groups (I) and (II). The filament group (I) is composed of a polyester selected from the group consisting of polyethylene terephthalate, polytrimethylene terephthalate and polytetramethylene terephthalate, and/or a blend and/or copolymer comprising at least two members selected from the polyesters. The filament group (II) is composed of a substrate composed of a polyester selected from the group consisting of polyethylene terephthalate, polytrimethylene terephthalate and polytetramethylene terephthalate, and/or a blend and/or a copolymer comprising at least two members selected from the polyesters and at least one polymer selected from the group consisting of styrene type polymers, methacrylate type polymers and acrylate type polymers, which is added to said substrate in an amount of 0.4 to 8% by weight based on the substrate.

Growing community of inventors

Ibaraki, Japan

Kohichi Iohara