Abstract: The present invention relates to a particular multi-layer microporous membrane having a good balance of important properties, including excellent electrochemical stability and low heat shrinkage, while maintaining high permeability and heat resistance, with good mechanical strength, compression resistance and electrolytic solution absorption. Of particular importance when used as a battery separator, the present multi-layer microporous membrane exhibits excellent heat shrinkage, melt down temperature and thermal mechanical properties, i.e. low maximum shrinkage in the molten state. The multi-layer microporous membrane of the present invention can be produced (or manufactured) by layering, such as for example by coextrusion, one or more microporous membrane second layers and one or more microporous membrane first layers, such as on one or both sides of a second layer.

Abstract: The invention relates to a particular multi-layer microporous membrane having a good balance of important properties, including excellent electrochemical stability and low heat shrinkage, while maintaining high permeability and heat resistance, with good mechanical strength, compression resistance and electrolytic solution absorption. Of particular importance when used as a battery separator, the present multi-layer microporous membrane exhibits excellent heat shrinkage, melt down temperature and thermal mechanical properties, i.e. low maximum shrinkage in the molten state. The multi-layer microporous membrane of the present invention is manufactured by layering, such as for example by coextrusion, one or more microporous membrane first layers and one or more microporous membrane second layers, such as on one or both sides of a first layer. The invention further relates to battery separators comprising the multi-layer microporous membrane and batteries utilizing the battery separators.

Abstract: The present invention relates to a yarn, comprising (a) a plurality of fibers having an orientation angle of no more than 8.0 degrees and made of a para-aramid having an inherent viscosity of 5.2 to 6.2 dl/g, (b) a linear density of at least 2666 dtex (2400 denier), (c) a modulus of at least 810 grams per dtex (900 grams per denier), and (d) a tenacity of at least 18 grams per dtex (20 grams per denier). The invention further relates to methods of making such yarn.

Abstract: The invention relates to a microporous membrane which comprises polyethylene, the microporous membrane having a differential pore volume curve with an area under the curve over the range of pore diameters of from about 100 nm to about 1,000 nm that is 25% or more of a total area under the curve over the range of pore diameters of from about 10 nm to about 1,000 nm.

Abstract: Embodiments of the present invention may provide a method of preparing biodegradable polyester polymer materials both in a filament type and a sheet type using a compressed gas. The method of the present invention comprises the following steps: 1) preparing biodegradable polyester polymers through a solution-state polymerization process of a cyclic monomer using a compressed gas as a reaction solvent in the presence of a catalyst; 2) performing a flash-spinning process of the biodegradable polyester polymers prepared above to form a polymer material in a filament type; and 3) performing a calendering process of the polymer material in a filament type prepared above to form a polymer material in a point-bonded sheet type.

Abstract: Polymer compositions comprising poly-glycolic acid (PGA) or a functional derivative thereof with a tensile strength of at least 1200 MPa are disclosed. Processes suitable for manufacturing said compositions are also described, comprising rendering PGA into an amorphous state then drawing to form a highly orientated polymer structure. The polymer compositions can be used to make artefacts, for example sutures, or used in combination with other polymers or non-polymeric substances to produce other artefacts, for example medical devices suitable for implantation into the human body. Processes for the production of said artefacts are also described.

Abstract: Described are fibers comprising a polyoxymethylene copolymer having an ISO 1133 MVR melt index (determined at 190° C. under a load of 2.16 kg) in the range from 0.3 to 30 ml/10 min which possess a bend recovery (measured by the double loop method in air and/or water) of not less than 125° C. These fibers are useful in brushes.

Abstract: The present invention relates to a thermo-shrinkable polyester film with a superior thermal shrinkage, which has an orientation angle of a molecular chain in a range of from 0° to about ±10° relative to a main shrinkage direction, and a molecular orientation ratio (MOR) in a range of from 1.29 to about 2.5, thereby preventing a label made from the film from curling or waving.

Abstract: Forming a fastener component having heads constructed to engage loops formed e.g. of fibers of a mating component, comprises forming, from a thermoformable material, a preform product having a sheet-form base and an array of preform stems integrally molded with and extending from the base to corresponding terminal ends, by a process having a machine direction and a cross-machine direction. Each molded stem has at least two terminal features spaced from one another in the cross-machine direction, the features having a transverse shape about which engaging fibers can bend, the features having a thickness of about 0.25 mm (0.010 inch) or less, preferably about 0.20 mm (0.008 inch), and for personal care products and the like preferably about 0.1 mm (0.004 inch) or less. The terminal ends of the features are heated to a predetermined softening temperature and the terminal ends are contacted to reform the terminal ends to form heads therefrom that overhang the sheet-form base sufficiently to engage loops.

Abstract: A method for forming a unitary polymeric projection or fastener comprising a thin, strong flexible backing, and a multiplicity of thin spaced hook members projecting from the upper surface of the unitary backing the method generally including extruding a thermoplastic resin through a die plate which die plate is shaped to form a base layer and spaced ridges, ribs or hook elements projecting above a surface of the base layer. When the die forms the spaced ridges or ribs the cross sectional shape of the hook members are formed by the die plate while the initial hook member thickness is formed by transversely cutting the ridges at spaced locations along their lengths to form discrete cut portions of the ridges. Subsequently longitudinal stretching of the backing layer (in the direction of the ridges on the machine direction) separates these cut portions of the ridges, which cut portion then form spaced apart hook members.

Abstract: A method of stretching films in which all or a portion of the width of the film is cooled during or just after stretching so as to improve the uniformity of the film. The includes stretching a polymeric film in a tenter that grasps the film with a plurality of clips along the opposing edges of the film and propels the clips to thereby stretch the film. The tenter includes driven clips and idler clips, with at least one idler clip between respective pairs of driven clips. The cooling is done so as to improve the uniformity of the clip spacing relative to the spacing obtained at otherwise identical process conditions without such cooling.

Abstract: A flat yarn of a high strength and a high modulus of elasticity, being excellent in solvent resistance, thermal stability and resistance to bending fatigue is provided. The flat yarn comprises polyoxymethylene copolymer containing 0.5 to 10 moles of specified oxyalkylene units per 100 moles of oxymethylene units in the polymer chain principally comprising repeating oxymethylene units and having a melt index at 190° C. with load of 2160 g of 0.3 to 20 g/10 min.

Abstract: A manufacturing system and method for use in the production of high strength plastic materials which can be used in the construction arts. The system and method includes a central rotary mold element which has vacuum means and cooling means placed inside thereof. Heating elements are positioned exteriorly of the rotary mold. Treated long fiber sheets are introduced to the rotary mold and combined with plastic sheets which are also fed to the mold.

Abstract: Improvements in preventing heat- and moisture-shrink problems in specific polypropylene tape fibers are demonstrated herein. Such fibers are manufactured through the initial production of polypropylene films or tubes which are then slit into very thin, though flat tape fibers thereafter. Such fibers include rigidifying nucleating compounds that nucleate polymer crystals within the target polypropylene after exposure to sufficient heat to melt the initial pelletized polymer and upon allowing such a melt to cool. Specific methods of manufacture of such inventive tape fibers, as well as fabric articles made therefrom, are also encompassed within this invention.

Abstract: The present invention provides a method for forming preferably a unitary polymeric hook fastener comprising a flexible backing, and a multiplicity of spaced hook members projecting from the upper surface of the unitary backing wherein each hook member comprises a multiplicity of hook head elements projecting in substantially the same direction. The hook members each comprise a stem portion attached at one end to the backing, and a head portion at the end of the stem portion opposite the backing. The head portion can also extend from a side of a stem portion or be omitted entirely to form alternative projections which can be other forms than a hook member. The head portion preferably projects past the stem portion on at least one of two opposite sides. At least the hook head portions have two or more hook head elements on at least one of the two opposing sides of the stem.

Abstract: A manufacturing system and method for use in the production of high strength plastic materials which can be used in the construction arts. The system and method includes a central rotary mold element which has vacuum means and cooling means placed inside thereof. Heating elements are positioned exteriorly of the rotary mold. Treated long fiber sheets are introduced to the rotary mold and combined with plastic sheets which are also fed to the mold.

Abstract: In a method and a device for continuously manufacturing films, webs, and sheets of plastics capable of forming optical images a melted plastic mass, pre-shaped as a sheet, is guided into a roller gap of a calender, the roller gap formed between a shaping engraving cylinder roller and a smoothing strip surrounding partially the shaping engraving cylinder roller. The shaping engraving surface of the cylinder roller is heated to melting temperature in the roller gap, wherein the melted plastic mass is applied directly onto the shaping engraving surface of the heated cylinder roller. A profiling is provided by cooling the melted plastic mass in the roller gap by heat removal on a side facing the shaping engraving surface.

Abstract: A process for preparing poly(trimethylene terephthalate) fibers including (a) providing a poly(trimethylene terephthalate) composition comprising about 0.05 to about 10 weight % ionomer and (b) spinning the polymer composition to form fibers. In addition, a poly(trimethylene terephthalate) fiber including poly(trimethylene terephthalate) with about 0.1 to about 10 weight % ionomer dispersed throughout the poly(trimethylene terephthalate), and use thereof in yarns, fabrics, and carpets, as well as the yarns, fibers and fabrics.

Abstract: A process for preparing poly(trimethylene dicarboxylate) multifilament yarns and monofilaments. One process for preparing poly(trimethylene dicarboxylate) multifilament yarns includes (a) providing a polymer blend including poly(trimethylene dicarboxylate) and about 0.1 to about 10 weight % styrene polymer, by weight of the polymer in the polymer blend, (b) spinning the polymer blend to form poly(trimethylene dicarboxylate) multiconstituent filaments containing dispersed styrene polymer, and (c) processing the multiconstituent filaments into poly(trimethylene dicarboxylate) multifilament yarn including poly(trimethylene dicarboxylate) multiconstituent filaments containing styrene polymer dispersed throughout the filaments. Another process includes spinning at a speed of at least 3,000 m/m and processing a blend including poly(trimethylene dicarboxylate) to form partially oriented poly(trimethylene dicarboxylate) multifilament yarn.

Abstract: A method for producing a flame retarding polypropylene fiber having both good flame retardancy and good fiber strength, and which generates no toxic gas, includes mixing 0.4% by wt. or more of a hindered amine-based stabilizer and 0.5% by wt. or more of a phosphoric ester-based flame retardant with a polypropylene resin having an MPR of 5 to 50 g/10 min, melt-spinning the mixture to form an undrawn yarn, drafting the yarn at a drafting magnification of 2 to 7 fold and a drafting temperature of 50 to 100° C., and further thermally setting at 60 to 140° C.

Abstract: The invention concerns a biaxially stretched and thermoset tubular seamless single- or multi-layered foodstuff skin wherein the layer, or, a multi-layered skin wherein at least one of the layers, contains a block copolymer with “hard” aliphatic polyamide blocks and “soft” aliphatic polyether blocks, the block copolymer corresponding to one of formulae (I) to (III), Ea—(NH—[CH2]x—CO)m—Xa—(A—O)n—A Xa—(CO—[CH2]x—NH)m—Ea (I), (II), —[X—(CO—[CH2]x—NH)o—Y—X—(A—O)p—A]-(III). The invention is particularly suitable as a skin for a sausage which is to be boiled or heated in water, and does not form folds when the filling is introduced manually, with no or only slight pressure.

Abstract: A drawn film production method including steps of drawing a crystalline thermoplastic resin film in the TD direction is characterized in that the orientation coefficient of the c-axis of the crystal of the thermoplastic resin in the film to the MD direction of the film is 0.8 or higher.

Abstract: A film made of a vinylidene-trifluoroethylene or tetrafluoroethylene copolymer is uniaxially drawn to fabricate a uniaxially drawn film. Then, the uniaxially drawn film is thermally treated at a temperature within a temperature range of the Curie temperature through the melting point of the vinylidene-trifluoroethylene or tetrafluoroethylene copolymer for five hours or over, to diffuse the molecular chains of the uniaxially drawn film along the orientation direction and thus, to remove the intertwining between the molecular chains.

Abstract: A process of manufacturing a sulfoaluminate or ferroaluminate cement, and an apparatus for the manufacture. The cement is manufactured from a mixture containing CaCO3, Al3 and/or Al(OH)3, CaSO4, SiO2 and/or a product containing silica or silicates such as clay, these compounds being present in the anhydrous or hydrated form. In this process, the mixture is treated up to clinkering by movement in a center of a kiln, in a sheet with approximately constant thickness, at approximately constant speed, along a treatment path having a positive temperature gradient, and for a treatment time during which the mixture remains below its melting temperature. The mixture is clinkered to produce a clinkered mixture that is cooled upon exit from the treatment path.

Abstract: A process for the preparation of a side-by-side or eccentric sheath-core bicomponent fiber wherein each component comprises a different poly(trimethylene terephthalate) composition.

Abstract: A method for forming a unitary polymeric projection or fastener comprising a base layer, and a multiplicity of spaced projections or hook members projecting from the upper surface of the unitary base layer the method generally including extruding of forming a thermoplastic resin through a die plate or mold. A die plate, if used, is shaped to form a base layer and spaced ridges, projecting above a surface of the base layer. When the die forms the spaced ridges or ribs the cross sectional shape of the projections are formed by the die plate. The ridges are then cut at spaced locations along their lengths to form discrete cut portions of the ridges. The cut portions are then heat treated resulting in shrinkage of at least a portion of at least the cut portion thickness by from 5 to 90 percent, preferably 30 to 90 percent thereby forming discrete upstanding projections.

Abstract: A soft stretch yarn produced by spinning yarn of conjugate fibers including two types of polyester in which one component is PTT at a take-up velocity of at least 1200 m/min, drawing at a drawing temperature of 50 to 80° C. at a draw ratio such that the drawn yarn tensile elongation is 20 to 45%, and then heat setting.

Abstract: An apparatus and method for producing self-texturing hollow fiber that exhibits a desirable tendency to coil rather than to bend sharply or zig-zag. In one embodiment the invention is a spinneret for the production of hollow filament having first and second curved slots where each slot is defined by a first end having a first width and a second end having a second width and where the first and second ends are separated by an intermediate portion possessing a non-uniform width. In another embodiment the invention is a method for of producing generally cylindrical hollow filaments comprising extruding a polymer melt through a spinneret having first and second curved slots where each slot has a first end having a first width and a second end having a second width and where the first and second ends are separated by a intermediate portion possessing a non-uniform width along the continuum defined by the distance between the first end and the second end.

Abstract: A process for producing a polyester sheet by dropping a molten polyester sheet extruded from an orifice-form nozzle on a cooling roll having the grooves of a large number of micro-cracks formed on the surface, closely adhering it to the cooling roll and solidifying it on the cooling roll, wherein the surface temperature (T, ° C.) of the molten polyester sheet 10 mm below the orifice-form nozzle is maintained at a temperature which satisfies the following expression (1): (Tc+20)° C.≦T≦(Tm+40)° C.  (1) wherein Tc and Tm are the falling temperature crystallization temperature (° C.) and melting point (° C.) of the polyester, respectively and T is as defined hereinabove, and the surface temperature of the cooling roll when it contacts the molten polyester sheet is controlled to a range of 5 to 100° C.

Abstract: The present invention is directed to a process for electrostatically spinning fibers of polyamic acid and the fibers thus produced as well as the nonwoven webs that may be formed from the fibers. According to the processes of the present invention, polyamic acid solutions may be electrostatically spun to form fibers of very small diameter, such as, for instance, less than about 5 &mgr;m in average diameter. The fibers may be formed into a nonwoven web having very high specific surface area and large porosity. The polyamic acid may be converted to polyimide to form a polyimide nonwoven web. The polyimide nonwoven web may then be activated through a carbonization process to enhance the electrochemical properties of the web. The nonwoven webs of the invention may be utilized in a variety of electrochemical applications including, for example, electrical double layer capacitors.

Abstract: A method including forming a pseudo-gel of a semi-crystalline polymer material and a solvent. The pseudo-gel is shaped into a first form and stretched. A portion of the solvent is removed to create a second form. The second form is stretched into a microstructure including nodes interconnected by fibrils. A method including forming a first form of a pseudo-gel including an ultra-high molecular weight polyethylene material and a solvent; stretching the first form; removing the solvent to form a second form; stretching the second form into a microstructure including nodes interconnected by fibrils; and annealing the stretched second form. An apparatus including a body portion formed of a dimension suitable for a medical device application and including a polyolefin polymer including a node and a fibril microstructure. An apparatus including a body portion including an ultra-high molecular weight polyolefin material including a node and a fibril microstructure.

Abstract: Thermally divisible multicomponent fibers (4) having at least a first component including an elastomeric polymer (6) and at least a second component including a non-elastomeric polymer (8). The multicomponent fibers are useful in the manufacture of nonwoven structures, and in particular nonwoven structures used as synthetic suede and filtration media.

Abstract: Polyester multi-filamentary yarn, useful as tire reinforcement, is produced by melting polyester resin at 290° C. or below including at least 90 mol % of polyethylene terephthalate with intrinsic viscosity of 0.7-1.2; filtering the molten resin for filtering retention time of ten minutes or below; spinning the filtered, molten resin by extrusion through a nozzle which has 250-500 holes, each ranging in diameter from 0.5 mm to 1.2 mm with a length/diameter ratio from 2 to 5; primarily quenching the extruded yarn at a temperature of 100-195° C. in a zone of 50 mm or more distance directly below the nozzle; secondarily quenching the yarn with air at its glass transition temperature (Tg) or below; taking off the yarn at spinning stress of 0.3 g/d or greater; drawing taken-off yarn at total draw ratio of 1.3 or greater; and thermally treating the yarn at temperature 150-230° C.

Abstract: A method of forming a fastener is provided, including (a) forming, from a thermoformable material, a preform product having a sheet-form base and an array of preform stems integrally molded with and extending from the base to corresponding terminal ends; (b) heating the terminal ends of the stems to a predetermined softening temperature, while maintaining the sheet-form base and a lower portion of each stem at a temperature lower than the softening temperature; and (c) contacting the terminal ends with a contact surface that is at a predetermined forming temperature, lower than the softening temperature, to deform the terminal ends to form heads therefrom that overhang the sheet-form base. Fasteners and other methods of forming them are also provided.

Abstract: A method for making a polymeric web exhibiting a soft and silky tactile impression on at least one side thereof. The method comprises the steps of providing a forming structure being moveable upon a forming drum and comprising a plurality of protrusions extending from the forming structure, the protrusions being generally columnar forms having an average aspect ratio of at least about 1. The forming structure is disposed adjacent a vacuum chamber and vacuum is applied at a sufficient level to induce a sufficient partial pressure to conform a precursor web to the forming structure, thereby forming the polymeric web. The precursor web can be cast directly onto the forming structure, or it can be re-heated by re-heat means to elevate its temperature sufficiently to permit vacuum formation.

Abstract: A method including forming a semi-crystalline polymer material into a lamella; and stretching the lamella into a polymer including a node of folded lamella and a fibril orientation. A method including extruding a pseudo-gel including an ultrahigh molecular weight polyethylene material into a lamella; stretching the lamella into a polymer including a node of folded lamella and a fibril orientation; and annealing the polymer at a temperature sufficient to define the node and fibril orientation. An apparatus including a body portion formed of a dimension suitable for a medical device application and including a semi-crystalline polymer arrayed in a node of folded lamella and a fibril orientation. An apparatus including a body portion including an ultra-high molecular polyethylene material arrayed in a node of folded lamella and a fibril orientation.

Abstract: The invention provides an improved method for making a poly(ester) bicomponent fiber wherein at least one poly(ester) contains a styrene polymer.

Abstract: A side-by-side or eccentric sheath-core bicomponent fiber wherein each component comprises a different poly(trimethylene terephthalate) composition and wherein at least one of the compositions comprises styrene polymer dispersed throughout the poly(trimethylene terephthalate), and preparation and use thereof.

Abstract: A process for making polyester film base material comprising more than 65 mol % of 1,4-cyclohexanedimethanol (CHDM) of the total glycol component in the polyester material. The film base is prepared by sequentially carrying out the following steps: (a) casting a molten polyester resin in a machine direction onto a casting surface to form a continuous sheet, (b) drafting the sheet by stretching in the machine direction at a stretch ratio of from 2 to 4, and at a temperature ranging from 70° C. to 130° C., (c) tentering the sheet in the transverse direction by stretching at a stretch ratio of from 2 to 4, and at a temperature ranging from 70° C. to 130° C. to obtain a biaxially oriented film, (d) heat-setting the oriented film at an actual temperature of from 160° C. to 200° C., and (e) cooling the heat-set film without substantial detentering to obtain a biaxially oriented, heat-set polyester-based film having a cutting index of 1 to 1.

Abstract: A polymer of a kind different from a polyester in an amount within the range of 0.3 to 5.0% by weight based on the polyester is added to the polyester, and the resulting composition is melt-extruded from the same pack. The extruded filament group including polyester multi-filaments is cooled once to the glass transition temperature or below, and the filament group is subsequently divided into two groups. One of the filament groups in an opened state is subjected to non-contact heat treatment at an atmospheric temperature of 120° C. or above; however, the other filament group is kept in a state without being subjected to the heat treatment. The respective filament groups are then simultaneously taken off at a speed of 2500 m/min or above and subjected to doubling and mixing of the filaments.

Abstract: Highly crimped, fully drawn bicomponent fibers, prepared by melt-spinning, followed by gas-flow quenching, heat treatment and high speed windup, are provided, as are fine-decitex and highly uniform polyester bicomponent fibers.

Abstract: The invention provides a poly(trimethylene terephthalate) drawn yarn pirn. The drawn yarn pirn of the invention comprises poly(trimethylene terephthalate) drawn yarn having an intrinsic viscosity of 0.7-1.3 dl/g, a heat shrinkage stress-exhibiting initial temperature of 55° C. or higher, a heat shrinkage stress extreme temperature of 150-190° C. and a breaking elongation of 36-60%, wound at a wound hardness of 80-90. The drawn yarn pirn of the invention exhibits satisfactory reelability even with high-speed false twisting, as well as minimal yarn breakage and fluff generation, thereby giving a textured yarn with satisfactory quality.

Abstract: Improved polypropylene fibers exhibiting greatly reduced heat- and moisture-shrink problems and including certain compounds that quickly and effectively provide rigidity to the target polypropylene fiber after heat-setting are disclosed herein. In such a manner, the “rigidifying” compounds provide nucleation sites for polypropylene crystal growth. After drawing the nucleated composition into fiber form, the fiber is then exposed to sufficient heat to grow the crystalline network, thus holding the fiber in a desired position. The preferred “rigidifying” compounds include dibenzylidene sorbitol based compounds, as well as less preferred compounds, such as sodium benzoate, certain sodium and lithium phosphate salts (such as sodium 2,2′-methylene-bis-(4,6-di-tert-butylphenyl)phosphate, otherwise known as NA-11).

Abstract: The present invention relates to a process for the production and for the spooling of preoriented polyester filaments comprising at least 90 weight %, relative to the total weight of the polyester filament, of polybutylene terephthalate (PBT) and/or polytrimethylene terephthalate (PTMT), preferably of PTMT, characterized in that: a) the spinline extension ratio is set in the range of 70 to 500; b) the filaments, immediately after exiting from the spinning nozzles, pass through a cooling delay zone from 30 mm to 200 mm in length; c) the filaments are cooled off to below the solidification temperature; d) the filaments are bundled at a distance of between 500 mm and 2500 mm from the lower side of the spinneret plate; e) the tension of the thread in front of and between the draw-off galettes is set to between 0.05 cN/dtex to 0.20 cN/dtex; f) the thread is spooled with a tension of the thread of between 0.025 cN/dtex to 0.15 cN/dtex; g) the spooling speed is adjusted to between 2200 m/min. and 3500 m/min.

Abstract: Improved polypropylene fibers exhibiting greatly reduced heat- and moisture-shrink problems and including certain compounds that quickly and effectively provide rigidity to the target polypropylene fiber after heat-setting are disclosed herein. In such a manner, the “rigidifying” compounds provide nucleation sites for polypropylene crystal growth. After drawing the nucleated composition into fiber form, the fiber is then exposed to sufficient heat to grow the crystalline network, thus holding the fiber in a desired position. The preferred “rigidifying” compounds include dibenzylidene sorbitol based compounds, as well as less preferred compounds, such as sodium beuzoate, certain sodium and lithium phosphate salts (such as sodium 2,2′-methylene-bis-(4,6-di-tert-butylphenyl)phosphate, otherwise known as NA-11).

Abstract: The invention relates to a raw material or masterbatch made from a thermoplastic and comprising silicon compounds, to a process for its production, and also to films produced using the polymer and having a thickness in the range from 0.5 to 1 000 &mgr;m. The polymer or masterbatch also comprises at least one stabilizer/free radical scavenger. The invention further relates to a process for producing the film.

Abstract: PTT staple fibers which are characterised by a novel combination of properties. In combination with novel stress-strain properties and modulus parameters, staple fibers or textiles or home textiles having extremely desirable aesthetics and service quality are obtained. Economical two-stage process for the production of PTT staple fibers. The melt spinning is carried out at a high polymer throughput and a spinning take-off speed of at least 600 m/min. In a separate fiber drawing frame, the stretching, heat-setting, crimping and drying are carried out.

Abstract: The object of the present invention is to provide melt-extrusion conditions and drawing process which enable to carry out stable and smooth fiber spinning of polyester produced by microorganisms, particularly P(3HB-CO-3HH) which conventionally had problems in spinning stability, as well as P(3HB) and P(3HB-CO-3HV). Another object of the present invention is to obtain filament having particular properties according to the process. The process comprises extruding a thermoplastic polymer from a melt-extruder, then rapidly cooling the same to at most the glass transition point of the polymer immediately after the extrusion to prevent the filament from blocking, and carrying out partial crystallization of the same rapidly at not less than the glass transition point.

Abstract: A bulky polyester multifilament composite yarn having a delicate hand and an appropriate bulkiness, which comprises two types of polyester filaments FA and FB differing from each other in average filament length, the FA being formed from a polyester resin containing 0.1 to 9.0% by mass of a micropore-forming agent (e.g., a polyoxyalkylene polyether, a metal organic sulfonate, a metal-containing phosphorus compound, and the like) and 0.5 to 5.0% by mass of a residual elongation improver (e.g., a polymer of methyl methacrylate, a polymer of a styrene compound, a polymer of a methylpentene compound, and the like) based on the mass of the polyester-resin, the FA having an average filament length that is from 1.07 to 1.40 times the average filament length of the FB, and the FA forming the peripheral portion of the composite yarn.

Abstract: A process for making load limiting yarn comprising making block copolymer and then spinning the block copolymer into yarn. The process employs a twin screw extruder and comprises (A) forwarding aromatic polyester melt to an injection position in a twin screw extruder, (B) injecting lactone monomer into the molten aromatic polyester, (C) dispersing the monomer into the aromatic polyester melt so that a uniform mixture forms in less than about thirty seconds, and (D) reacting the uniform mixture resulting from step (C) at a temperature from about 250° C. to from a block copolymer. Steps (A) through (D) occur in less than about four minutes residence time in the twin screw extruder. The process is advantageous because high IV starting aromatic polyester can be used and the short reaction time at high temperature results in block copolymer with minimum transesterification, a high melting point, and a high melt viscosity.