Abstract: A batch-type polyester polymerization apparatus manufactured by assembling a conventional batch-type apparatus with a thin film tower. The batch-type polyester polymerization apparatus is advantageous in that oligomer is polymerized while forming a polyester thin film on each inclined plate of a thin film tower, and a polycondensation reaction is conducted in a polycondensation reactor as well as the thin film tower, thus greatly reducing polymerization time.

Abstract: A method of producing a polyethylene terephthalate-based polyester fiber includes spinning polyethylene terephthalate based polyester to produce an undrawn yarn with an intrinsic viscosity of 0.83 or more and a density of 1338 g/cm3 or more, multi-stage drawing the undrawn yarn, heat-setting the drawn yarn, relaxing heat-set yarn, and winding the relaxed yarn to produce the resulting drawn yarn with an intrinsic viscosity of 0.83 or more and a density of 1.38 to 1.3865 g/cm3, so that the thusly produced industrial polyester yarn with high modulus and low shrinkage contributes to significantly improving strength retention (tenacity of a dip cord/tenacity of a grey yarn) of the dip cord, produced by treating the polyester yarn with an adhesive (RFL) and subsequently heat-treating the RFL-treated polyester yarn, to be useful as a tire cord.

Abstract: The present invention relates to cellulose fiber containing 500 to 2000 of filaments and having homogeneous physical properties and the multi-filaments according to the present invention is characterized in that the strength and the breaking elongation of the multi-filaments are 4 to 9 g/d and 4 to 15%, respectively. In particular, the present invention is characterized in that each mono-filament selected 100 strands from every three part divided from multi-filaments has properties as following: (a) 3 to 9 g/d in average strength, 7 to 15% in average breaking elongation and 0.035 to 0.055 in by birefringence, (b) the differences of the above three parts are below 1.0 g/d in average strength, 1.5% in breaking elongation and 0.7 denier in denier, (c) the CV (%)(coefficient of variation) of the above three parts are below 10%, and (d) the birefringence differences of the above three parts are below 0.004.

Abstract: There is provided with a cellulose fiber suitable for industrial material which is produced by a process comprising following steps: producing NMMO solution made in a manner to dissolve 0.1 wt % to 10 wt % of salt and polyvinyl alcohol in concentrated N-Methyl Morpholine N-oxide (NMMO) in liquid state; producing cellulose solution in a manner that said NMMO solution is mixed with cellulose powder and then said cellulose powder is swelled to produce cellulose solution; obtaining multifilament by solidifying said cellulose solution reached at a coagulation bath through air layer after extruded-sprayed with spraying nozzle having orifices of 500 to 2000; and winding said multifilament for storing after in turn washing, drying and treating with organic solvent, and the cellulose fiber according to the present invention is suitable for industrial materials due to excellent mechanical strength.

Abstract: This invention relates to a poly(trimethylene terephthalate) BCF carpet yarn having a Y-shaped cross-section that has an modification ratio and a arm angle within a specific range, and a method for preparing it. The BCF carpet yarn has excellent bulk property and spinning efficiency, and a carpet made from it has good appearance, sense of touch, and tufting efficiency.

Abstract: The present invention relates to a method for making highly homogenized cellulose solution, wherein the cellulose solution is obtained by obtaining a solidified N-methylmorphorine-N-oxide (hereinafter, referred to as ‘NMMO’) hydrates which is solidified a liquid-state NMMO hydrates comprising 10 to 18% by weight water by using a simple screw-type feeder and by controlling the temperature, feeding the solidified NMMO into a twin-screw type extruder continuously, obtaining a cellulose solution which is fully swelled in a few minutes by dispersing and mixing with cellulose powder in the twin-screw type extruder, and extruding a highly homogenized cellulose solution by feeding the obtained cellulose solution into a melting zone of the extruder to melting the cellulose solution in a few minutes by minimum heat and shear force.

Abstract: This invention relates to a method of preparing cellulose solution which is homogeneous at relatively low temperature, in which a small amount of cellulose powder or polyvinylalcohol is dissolved in the liquid-state, concentrated N-methylmorpholine-N-oxide (hereinafter, referred to as ‘NMMO’) so as to lower the solidifying temperature of NMMO, and then, the resulting solution and cellulose powder are fed into an extruder so as to be mixed, swollen and melted in the extruder.

Abstract: Disclosed is a fluorescent elastic yarn and method for producing the same. The fluorescent elastic yarn which is finished with the spinfinish oil containing the fluorescent agent can fluoresce sufficiently to allow a fine elastic yarn to be seen by the naked eye when ultraviolet light is irradiated to the fluorescent elastic yarn. Therefore, the fluorescent elastic yarn of the present invention is advantageous in that CSY (Core spun yarn) producers are able to identify its presence inside of the hard fiber covering it more easily and timely and thus minimize the numbers of inferior CSY products which are not spun with elastic yarn strands.

Abstract: The present invention relates to, and more particularily, to a lyocell dip cord and tire produced by a method comprising the steps of: (A) dissolving 0.01 to 3 wt % of cellulose powder in portions in concentrated liquid N-methylmorpholine N-oxide (NMMO) to prepare cellulose-containing NMMO solution; (B) feeding the NMMO solution and cellulose powder into an extruder having a screw to be subjected to dispersing, mixing, shearing, kneading, melting and measuring ability in the extruder to prepare a swollen and homogenized cellulose solution; (C) spinning the cellulose solution through a spinning nozzle, passing the spinning solution through an air gap to a coagulation bath and coagulating the spinning solution to obtain a multifilament; (D) subject the multifilament to water-wash, drying and oil-treatment, followed by winding; and (E) twisting the wound yarn with a twisting machine to prepare a greige cord, weaving the greige cord and dipping the woven cord in a dipping solution.

Abstract: Disclosed is a method of producing a polyethylene terephthalate-based polyester fiber, including spinning polyethylene terephthalate based polyester to produce an undrawn yarn with an intrinsic viscosity of 0.83 or more and a density of 1.338 g/cm3 or more, multi-stage drawing the undrawn yarn, heat-setting the drawn yarn, relaxing the heat-set yarn, and winding the relaxed yarn to produce the resulting drawn yarn with an intrinsic viscosity of 0.83 or more and a density of 1.38 to 1.3865 g/cm3. Compared to a prior polyester yarn with high modulus and low shrinkage, produced according to conventional melt-spinning and drawing processes, an industrial polyester yarn with high modulus and low shrinkage according to the present invention contributes to significantly improving strength retention (tenacity of a dip cord/tenacity of a grey yarn) of the dip cord, produced by treating the polyester yarn of the present invention with an adhesive (RFL) and subsequently heat-treating the RFL-treated polyester yarn.

Abstract: The present invention relates to a high tenacity polyethylene naphthalate fiber containing a silica compound. This fiber is produced by a method comprising the steps of: (A) melt-spinning a solid phase-polymerized polyethylene-2,6-naphthalate chip containing ethylene-2,6-naphthalate units at more than 85 mole % and a silica compound and having an intrinsic viscosity of 0.70-1.20, to produce a melt-spun yarn; (B) passing the melt-spun yarn through a retarded cooling zone and a cooling zone to solidify the yarn; (C) withdrawing the yarn at such a speed that the undrawn yarn has a birefringence of 0.001-0.1; and (D) subjecting the undrawn yarn to multi-stage drawing at a total draw ratio of at least 1.5 and a drawing temperature of 50-250° C.

Abstract: Disclosed is a potentially elastic Interlaced-textured yarn including a potentially crimped yarn and a composite filaments interlaced with each other, and an elastic woven fabric produced using the same. The potentially elastic interlaced-textured yarn is produced by interlacing the PET/PTT polyester-based potentially crimped yarn with an ultrafine yarn having a monofilament fineness after the weight reduction by alkali treatment of 0.01 to 0.5 deniers and a total fineness of 30 to 300 deniers. At this time, the ultrafine yarn is selected from the group consisting of a sea-island type composite filaments, a radial type composite filaments, and a yarn produced through a direct spinning process. Furthermore, the potentially elastic interlaced-textured yarn has elasticity of 15 to 40%, and the woven fabric has superior elastic recovery, elasticity recovery, drape, and dyeability, in addition having soft, suede-like texture.

Abstract: The present invention relates to a polyamide fiber for uncoated airbags, the fineness and stress-strain curve of the monofilaments of which were controlled such that the polyamide fiber can absorb impact energy which occurs instantaneously when the airbags operate. More particularly, the present invention relates to a high strength polyamide fiber consisting of polyamide monofilaments each having a fineness of less than 4 denier and a stress-strain curve where (a) the monofilament elongates less than 5% when subjected to an initial stress of 1.0 g/d, (b) it elongates less than 12% when subjected to a middle stress of 4.5 g/d, and (c) it elongates more than 3% over a tensile strength range from a tensile strength of at least 9.0 d/g to the tensile strength at break of the monofilament, the elongation values being measured at ambient temperature. A fabric produced using the inventive polyamide fiber has high tensile strength and high tear strength, so that it will be useful as an uncoated fabric for airbags.

Abstract: The present invention relates to a high tenacity, high modulus and low shrinkage lyocell multifilament yarn suitable for use in tire cords and MRG (mechanical rubber goods). The lyocell multifilament yarn is a cellulose-based fiber for industrial applications, which is produced by dissolving pulp having a degree of polymerization (DPW) of 700-2,000 and preferably 800-1,400, and a ?-cellulose content of more than 90% and preferably more than 92%, in N-methylmorpholine N-oxide (NMMO) hydrate, at a pulp concentration of 5-15% by weight and preferably 8-13% by weight. The lyocell monofilament according to the present invention is characterized by the following stress-strain profile: (1) the lyocell monofilament analyzed after drying is elongated by less than 3.0% and has an initial modulus of 150-400 g/d, when it was subjected to an initial stress of 3.0 g/d; (2) it is elongated by 3.0-7.0% when it was subjected to a stress greater than the initial stress but smaller than 6.

Abstract: The present invention relates to crosslinked polyvinyl alcohol raw cord and method for producing the same, and more particularly, to crosslinked polyvinyl alcohol fiber, in which PVA resin having a degree of polymerization of more than 1,000 and a degree of saponification of more than 97.0 mol % is dissolved in dimethyl sulfoxide, the solution is subjected to dry and wet gel spinning using methanol as a coagulation solution, drawn and thermally treated, the resulting polyvinyl alcohol drawn yarn with 500-3,000 deniers is twisted to produce a cabling yarn, the cabling yarn is plied into a 2-ply or 3-ply yarn to produce a raw cord, the raw cord is wound on a bobbin for crosslinking and crosslinked in an aqueous crosslinking solution containing an aromatic aldehyde compound and an acid catalyst. Moreover, the present invention relates to a crosslinker-introducing apparatus, which is used in the above method and can effectively induce the crosslinking reaction of the wound raw cord.

Abstract: Disclosed is a potentially elastic interlaced-textured yarn including a potentially crimped yarn and a composite filaments interlaced with each other, and an elastic woven fabric produced using the same. The potentially elastic interlaced-textured yarn is produced by interlacing the PET/PTT polyester-based potentially crimped yarn with an ultrafine yarn having a monofilament fineness after the weight reduction by alkali treatment of 0.01 to 0.5 deniers and a total fineness of 30 to 300 deniers. At this time, the ultrafine yarn is selected from the group consisting of a sea-island type composite filaments, a radial type composite filaments, and a yarn produced through a direct spinning process. Furthermore, the potentially elastic interlaced-textured yarn has elasticity of 15 to 40%, and the woven fabric has superior elastic recovery, elasticity recovery, drape, and dyeability, in addition having soft, suede-like texture.

Abstract: Method for manufacturing polyester fibers comprising melt-extruding a polymer without increasing an intrinsic viscosity of the polymer during spinning to minimize a reduction of the intrinsic viscosity of the polymer; maintaining a low atmospheric temperature directly below a nozzle to maximize a degree of orientation of undrawn yarn; winding the polymer at 2,000 m/min or more to produce a undrawn yarn, followed by drawing the undrawn yarn through continuous three phases at low temperature. The method has advantages in that high strength and low shrinkage polyester fibers with a uniform fineness and physical properties can be manufactured at high spinning efficiency, without formation of broken filament and curved filament, by preventing formation of a vortex of cooling air with the use of eddy plates directly below a nozzle.

Abstract: Process for preparing an industrial polyester multifilament yarn with high modulus and low shrinkage, in which polyethylene terephthalate polyester is wound at 2000 m/min or more to produce undrawn yarns with an intrinsic viscosity of 0.88 or higher and a density of 1.338 to 1.365 g/cm3, an oiling agent is provided to undrawn yarns, the resulting undrawn yarns are wound, drawn through three stages, heat set, relaxed, and wound again. The polyethylene terephthalate polyester yarn is produced by drawing undrawn yarns at a glass transition temperature (Tg, about 80° C.) or lower through three stages under conditions that a draw ratio of the 1st stage is greater than a draw ratio of the 2nd stage or a draw ratio of the 3rd stage and the draw ratio of the 3rd stage is greater than the draw ratio of the 2nd stage.

Abstract: The present invention relates to a method for producing tire using high strength lyocell dip cord, and more particularity, to a lyocell dip cord and tire produced by a method comprising the steps of: (A) dissolving 0.

Abstract: Disclosed is a lyocell multi-filament for a tire cord and a method of producing the same. The method includes i) dissolving mixed powder of cellulose and polyvinyl alcohol in a mixed solvent of N-methyl morpholine N-oxide and water to prepare a dope, ii) extruding the dope using a spinning nozzle including orifices through air gaps into a conical upper coagulation bath to solidify the dope to produce a multi-filament, iii) feeding the multi-filament through a lower coagulation bath to a washing bath, and washing the multi-filament, and iv) drying and oiling the washed multi-filament and winding the resulting multi-filament. At this time, the orifices each have a diameter (D) of 100 to 300 ?m, a length (L) of 200 to 2400 ?m, and a ratio of the length to the diameter (L/D) of 2 to 8, and are spaced apart from each other at intervals of 2.0 to 5.0 mm.