Abstract: A swim fin is provided that is placed between a user's foot and the sole of a foot covering. The fin is generally planar and fin-shaped, having a heel end and a toe end, with opposing lateral sides extending between the toe end and the heel end. An optional tab(s) is located at one of the lateral sides and spaced distantly from the toe end, and may terminate in a enlarged terminal end that projects inwardly. A groove is formed between the tab and the heel end. Binding members, such as straps of a sandal, are inserted into the groove.

Abstract: A swim fin is provided that is placed between a user's foot and the sole of a foot covering. The fin is generally planar and fin-shaped, having a heel end and a toe end, with opposing lateral sides extending between the toe end and the heel end. An optional tab(s) is located at one of the lateral sides and spaced distantly from the toe end, and may terminate in a enlarged terminal end that projects inwardly. A groove is formed between the tab and the heel end. Binding members, such as straps of a sandal, are inserted into the groove.

Abstract: In an improved power transmission belt, the circumferentially disposed reinforcing cords are made from multi-filament yarns of heterofilaments. These cords, when fused, have good inter-filament bonding without the solvent of the solvent/adhesive systems.

Abstract: The invention is directed to LCP monofilaments and yarn made therefrom which have improved adhesion properties, said monofilaments, and yarn made therefrom, comprising a liquid crystalline polymer filament having a finish selected from the group consisting of esters formed between (a) pentaerythritol and saturated polyols of up to 10 carbon atoms and 2 to 6 hydroxyl groups, and (b) a carboxylic acid of formula C.sub.x H.sub.2x=1 COOH, wherein x is from 2 to 20, and wherein 2 to 6 of the hydroxy functions are converted to ester functions. In a preferred embodiment of the invention the finish is an ester formed from the reaction of pentaerythritol and a carboxylic acid of formula C.sub.x H.sub.2x=1 COOH, wherein x is from 2 to 20, and preferably between 14 and 20. The most preferred esters are pentaerythritol tetrapelargonate and pentaerythritol tetraisostearate.

Abstract: A heterofilament of a PBT sheath, a multifilament composite yarn composed of a plurality of heterofilaments having PBT sheath, and a conductive bundle containing a wire wrapped with a plurality of the multifilament composite yarn.

Abstract: A process for high stress spinning of polyethylene terephthalate yarns to produce a yarn of improved mechanical properties is disclosed. The process of the invention is conducted by spinning polyethylene terephthalate polymer through a spinneret having a plurality of rows of orifices wherein at least one row of orifices is larger than adjacent row of orifices. The yarn is quenched by contacting filaments issuing from the larger orifice with a quench medium prior to contacting of the yarn issuing from the orifices of smaller size. Thereafter, the yarn is drawn at a draw ratio which is at least about 85% of the maximum draw ratio of the yarn. A yarn having improved strength and/or a reduced fray levels is produced.

Abstract: The aging period for chemically stabilized, adhesive activated polyester material can be reduced by contacting the material before it is substantially drawn or stretched with a composition containing a defined epoxide compound catalyzed with ions of at least one of potassium, cesium, rubidium or ammonium at a pH of between about 7.5 to about 13.0. The composition preferably also contains chloride, bromide or iodide ions which stabilizes the pH and/or an amine which improves adhesion to rubber.

Abstract: An apparatus and process for the continuous manufacture of high stress, high denier industrial yarn spun from polyethylene terephthalate polyester. A control system continuously measures melt viscosity of the polymer both at the outlet from a polymerization zone and at a downstream location adjacent a manifold immediately preceding a plurality of spinnerettes through which the polymer is drawn into filamentary material. Adjustments are continuously made to a meaningful operating condition within the polymerization zone, such as the magnitude of the vacuum therein, whenever IV inferred from operating data strays from a pre-established level. Adjustments are also regularly made at discrete short term intervals, for example, minute by minute, whenever viscosity at the outlet from the polymerization zone strays from the pre-established level.

Abstract: Melt extruded poly(6-oxy-2-naphthoate-4-oxybenzoate) shaped articles of relatively high strength and modulus are produced in a lesser period of time than commonly heretofore required in the prior art. The required polymer is capable of exhibiting an anisotropic melt phase and is formed through the reaction of 6-acetoxy-2-naphthoic acid and 4-acetoxybenzoic acid under a combination of melt polymerization conditions which surprisingly has been found to yield a shaped article following melt extrusion which may be heat strengthened in an unusually brief period of time (i.e. two hours or less). The polymerization is catalyzed by a potassium salt (e.g. potassium acetate), and the polymerization conditions require a relatively highly elevated final polymerization temperature. Substantially all of the acetic acid by-product is removed from the polymerization zone prior to concluding the polymerization under reduced pressure conditions.

Abstract: A slit extrusion die with a modified entry port which allows extrusion of a low denier tape at high draw down ratios is disclosed. The die has an entry port wherein the depth of the slit is greater at both ends than at the middle by an amount equal to 0.1 to 0.4 times the length of the slit.

Abstract: A low denier, high tenacity poly(ethylene terephthalate) fibrillated tape yarn particularly suited for conversion into a sewing thread which exhibits excellent sewing performance is produced by intimately mixing poly(ethylene terephthalate) polymer with from about 0.1 to 20 percent polypropylene based on the weight of poly(ethylene terephthalate), extruding the polymer mixture in the form of a tape through a slit die having a modified entry port wherein the depth of the slit is greater at both ends than at the middle, at a melt draw down of from about 26:1 to about 75:1, quenching said tape, hot drawing said tape in two stages wherein said tape is initially hot drawn to a draw ratio of from about 3.3 to about 4.2 while being subjected to a temperature of from about 80 to about 140 degree centigrade, thereafter hot drawing to a total draw ratio of about 5.0 while heated to a temperature about 160 degrees and thereafter subjecting the tape to fibrillation.

Abstract: A low denier, high tenacity poly(ethylene terephthalate) fibrillated tape yarn particularly suited for conversion into a sewing thread which exhibits excellent sewing performance is produced by intimately mixing poly(ethylene terephthalate) polymer with from about 0.1 to 20 percent polypropylene based on the weight of poly(ethylene terephthalate), extruding the polymer mixture in the form of a tape through a slit die having a modified entry port wherein the depth of the slit is greater at both ends than at the middle, at a melt draw down of from about 26:1 to about 75:1, quenching said tape, hot drawing said tape in two stages wherein said tape is initially hot drawn to a draw ratio of from about 3.3 to about 4.2 while being subjected to a temperature of from about 80.degree. to about 140.degree. centigrade, thereafter hot drawing to a total draw ratio of about 5.0 while heated to a temperature about 160.degree. and thereafter subjecting the tape to fibrillation.

Abstract: A low denier, high tenacity poly(ethylene terephthalate) fibrillated tape yarn particularly suited for conversion into a sewing thread which exhibits excellent sewing performance is produced by intimately mixing poly(ethylene terephthalate) polymer with from about 0.1 to 20 percent polypropylene based on the weight of poly(ethylene terephthalate), extruding the polymer mixture in the form of a tape through a slit die having a modified entry port wherein the depth of the slit is greater at both ends than at the middle, at a melt draw down of from about 26:1 to about 75:1, quenching said tape, hot drawing said tape in two stages wherein said tape is initially hot drawn to a draw ratio of from about 3.3 to about 4.2 while being subjected to a temperature of from about 80.degree. to about 140.degree. C, thereafter hot drawing to a total draw ratio of about 5.0 while heated to a temperature about 160 degrees and thereafter subjecting the tape to fibrillation.