Abstract: The invention provides novel polyether hydroxycarboxylate copolymers which are effective sequestering agents. The polyether hydroxycarboxylate copolymer when used in a cleaning composition enhances or “builds” the cleaning efficiency of the surfactant by inactivating hardness ions. In addition, the polyether hydroxycarboxylate copolymers assist in cleaning by dispersing and suspending soils to prevent the redeposition of soils. The polyether hydroxycarboxylate copolymer has the structure wherein M+ is a cation wherein M is independently selected from hydrogen, ammonia, alkali metals, alkaline earth metals, zinc, copper, organic amines, amino acids, and amino saccharides; R2 and R3 are independently hydrogen or a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms; n is from about 2 to about 100; x1 and x2 are independently 0 or 1; a is from 0 to 99 mole percent; and b is from 100 to 1 mole percent, provided that (a+b) is 100 mole percent.

Abstract: An aliphatic copolyester having a plurality of first: ester units of the formula: —CO—[R1]t—CO—O—R2—O— wherein R1 represents a divalent aliphatic group, R2 represents a divalent aliphatic and t is an integer of 0 or 1, and a plurality of second ester units of the formula: wherein R1 and t are as defined above and R3 represents an aliphatic group. The molar ratio of the first ester unit to the second ester unit is 90:10 to 99.9:0.1. The copolyester is produced by reacting an aliphatic diester with an aliphatic glycol and with a monoacylated glycerin under ester exchanging conditions.

Abstract: The invention relates to a polymer prepared from the repeat units of residues of a monomer of at least one dicarboxylic acid or ester; a monomer comprising a diol, diamine or a mixture thereof; a monomer comprising at least one sulfonate group and at least one polyester reactive group, and a monomer comprising an optical brightener agent having at least one polyester reactive group. The invention further relates to a method for preparing a polymer. The invention further relates to method of marking an article or composition with the polymer. The invention further relates to a method for detecting and separating an article contacted with the polymer. The invention further relates to an article or composition contacted with the polymer. The invention further relates to a method for enhancing the optical brightness of an article or composition, by contacting the article or composition with the polymer.

Abstract: A method of forming an esterification product Comprises providing (1) a material selected from the group consisting of ester monomers, ester oligomers, ester polymers, and mixtures thereof, and (2) a catalyst selected from the group consisting of: ##STR1## and mixtures thereof. wherein D is selected from the group consisting of carbon and silicon; Q is selected from the group consisting of O, S, and NR; M is selected from the group consisting of sodium, lithium, potassium, rubidium, and cesium; R, R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, R', R", and R'" are each independently selected from the group consisting of H, O, halogen, Si, N, S, P, C.sub.1 to C.sub.20 linear or branched alkyl, C.sub.3 to C.sub.10 cycloalkyl, and aromatic; and reacting the material in the presence of the catalyst to form an esterification product.

Abstract: The invention relates to amorphous and crystalline fibers, particularly binder fibers, made from polyesters and the polyesters themselves. The polyesters of the invention are generally formed from a glycol component, such as a five carbon glycol, and a dicarboxylic acid component. The polyesters may be formed into a variety of products, for example fibers, composites and other molded articles. Preferably the polyesters are binder fibers for nonwovens, textile and industrial yarns and fabrics.

Abstract: The invention relates to fibers, particularly binder fibers, made from copolyesters and the copolyesters themselves. The copolyesters of the invention are generally formed from 1,3- or 1,4-cyclohexanedimethanol, ethylene glycol and isophthalic acid or esters thereof and at least one dicarboxylic acid selected from terephthalic acid, naphthalenedicarboxylic acid, 1,3- or 1,4-cyclohexanedicarboxylic acid or esters thereof. Such copolyesters may be formed into a variety of products, especially binder fibers for nonwoven fabrics, textile and industrial yarns, and composites.

Abstract: A process for the preparation of an unsaturated polyester which comprises (i) reacting an organic diol with a cyclic akylene carbonate in the presence of a first catalyst to thereby form a polyalkoxy diol, and (ii) optionally adding thereto a further amount of cyclic alkylene carbonate in the presence of a second catalyst, and (iii) subsequently polycondensing the resulting mixture with a dicarboxylic acid.

Abstract: A process is disclosed for the preparation of a polyester polymer or polyester copolymer under superatmospheric pressure conditions in a pipe or tubular reaction under turbannular flow conditions. Reaction material having a glycol equivalents to carboxylic acid equivalents mole ratio of from 1.0:1 to 1.2:1, together with a superatmospheric dense gaseous medium are fed co-currently to the reactor. Dicarboxylic acid and/or diol raw materials may be injected into any of the reaction zones in the process during operation to achieve the overall desired mole ratio balance. The process operates at temperatures of from about 220.degree. C. to about 320.degree. C., with turbannular flow achieved before the polymer product and gas exit the reactor process. The pressure in the reaction zones can be in the range from 15 psia to 2500 psia.

Abstract: An organic oligomer binder produced by depolymerizing virgin, scrap, recycled or reclaimed polyethylene terephthalate via an alcoholysis reaction with branched glycols and esterifiing the resulting polyol oligomer with polybasic carboxylic acids and/or anhydrides.

Abstract: A process for co-polymerizing unsaturated vegetable oils or fatty acids utilizing the steps of mixing the unsaturated vegetable oil or fatty acid with maleic anhydride in a container. Simultaneously, inert gas is added to the container to provide an oxygen free environment within the container. A sufficient amount of initiator is added to the mixture in the container to produce free radicals for the co-polymerization of the vegetable oil with this fatty acid or the maleic anhydride.

Abstract: The present invention discloses a process for producing molded, shaped or extruded articles comprising the steps of:a) melt reacting, in the presence of a catalyst which is substantially free of Co compounds, at least one glycol and at least one dicarboxylic acid to form a polyester having an I.V. of at least about 0.5 dL/g, wherein said at least one glycol is selected from the group consisting of glycols having up to 10 carbon atoms and mixtures thereof and said dicarboxylic is selected from the group consisting of alkyl dicarboxylic acids having 2 to 16 carbon atoms, aryl dicarboxylic acids having 8 to 16 carbon atoms and mixtures thereof;b) adding an acetaldehyde reducing additive to said polyester to form a reduced acetaldehyde polyester; andc) forming said reduced acetaldehyde polyester into articles directly from step b.Thus, the present invention provides a process for directly producing from the melt article having extremely low acetaldehyde content.

Abstract: The process for preparing polyethylene naphthalate according to the invention is intended to obtain polyethylene naphthalate having a low impurity content from naphthalenedicarboxylic acid containing impurities.

Abstract: A catalyst composition is disclosed. The composition comprises a titanium compound, a complexing agent, a solvent, and optionally a cocatalyst. The cocatalyst can be a cobalt/aluminum catalyst, an antimony compound, or combinations thereof. Also disclosed is a process for producing the composition. The process comprises combining a titanium compound, a complexing agent, a solvent, and optionally a cocatalyst. Further disclosed is a process for using the composition which comprises contacting a carbonyl compound, in the presence of the composition, with an alcohol under a condition suitable for esterification, transesterification, polymerization, or combinations thereof.

Abstract: A catalyst composition is disclosed. The composition comprises a titanium compound, a phosphorus compound, an amine, a solvent and optionally a cocatalyst in which the phosphorus compound has a formula selected from the group consisting of (R.sup.1 O).sub.x (PO)(OH).sub.3-x, (R.sup.1 O).sub.y (P.sub.2 O.sub.3)(OH).sub.4-y, and combinations thereof; the amine is a tertiary amine; each R.sup.1 is independently a linear or branched alkyl radical containing from 1 to about 20 carbon atoms per radical; x is 1 or 2; and y is 1, 2, or 3; and the cocatalyst can be a cobalt/aluminum catalyst, an antimony compound, or combinations thereof. Also disclosed is a process for producing the composition. The process comprises combining a titanium compound, a phosphorus compound, a solvent, an amine, a solvent, and optionally a cocatalyst. The phosphorus compound, amie, and solvent are the same as those disclosed above.

Abstract: A polyester polymer and method for making the polyester, wherein the polyester is prepared by (1) combining in a reactor a monomer containing a diacid moiety; a monomer comprising a diol moiety; and a monomer containing an isosorbide moiety; with a condensation catalyst suitable for condensing aromatic diacids and diols; and (2) heating the monomers and catalyst to polymerize the monomers to yield a polyester having an inherent viscosity of at least about 0.15 dL/g.

Abstract: A polyester fiber made from a polymer having ethylene glycol moieties, isosorbide moieties and terepthaloyl moieties, and the method of making the fiber is described. The polyester fiber is used to form articles suitable for commercial, especially textile, and industrial uses, and has an inherent viscosity of at least 0.35 dL/g when measured as a 1% (weight/volume) solution of the polyester in o-chlorophenol at a temperature of 25.degree. C.

Abstract: A process for the preparation of an unsaturated polyester which comprises (i) reacting an organic diol with a cyclic akylene carbonate in the presence of a first catalyst to thereby form a polyalkoxy diol, and (ii) optionally adding thereto a further amount of cyclic alkylene carbonate in the presence of a second catalyst, and (iii) subsequently polycondensing the resulting mixture with a dicarboxylic acid.

Abstract: Polymers based ona) lactic acid or its C.sub.1 -C.sub.4 alkyl esters or mixtures thereof,b) at least one aliphatic C.sub.4 -C.sub.10 dicarboxylic acid andc) at least one C.sub.3 -C.sub.10 alkanol containing from three to five hydroxyl groups.

Abstract: A process for producing an aromatic polyester by esterifying a dicarboxylic acid mainly composed of an aromatic dicarboxylic acid and a glycol mainly composed of ethylene glycol in the presence of 1 to 30 mmol %, based on the dicarboxylic acid, of a quaternary phosphonium sulfonate having ester-forming functional group(s), and then polycondensing the resulting product.

Abstract: A method for preparing polyester films, which comprises addition of partially esterified trimellitate at any stage of the polymerization of polyester through direct esterification or ester interchange, the partially esterified trimellitates resulting from salt formation of partial esterified trimellitic acids which are prepared by partial esterification of aromatic tricarboxylic acids selected from trimellitic acid and trimellitic anhydride with alcohols selected from alkyl alcohols and alkylene alcohols. The polyester film prepared the composition has little voids by virtue of good affinity of the particles originating from the partially esterified trimellitates with polyester and thereby not easily broken when forming films. In addition, it is easy to control particle content and size. Further, fine protrusions can be repeatitively formed in the final films, with ease, giving high abrasion resistance and slip property to the film.

Abstract: New copolyester composition that provides excellent filament spinning and mill/yarn processing of staple fiber into fabrics having combination of excellent pilling performance as well as aesthetics and tactility ("hand"). Preferred fibers have non-round cross-sections, especially multi-grooved and scalloped-oval cross-sections that provide fabrics having outstanding comfort qualities of moisture-management, dryness and comfort, as well as minimal pilling.

Abstract: A process which can be used in oligomerization, polymerization, or depolymerization such as, for example, the production of a polyester is provided. The process comprises contacting a carbonyl compound, in the presence of a composition, with an alcohol. The catalyst comprises a catalyst having the formula of M.sub.x Ti.sup.(III) Ti.sup.(IV).sub.y O.sub.(x+3+4y)/2 wherein M is an alkali metal, Ti.sup.(III) is titanium in the +3 oxidation state, Ti.sup.(IV) is titanium in the +4 oxidation state, x and y are numbers greater than or equal to zero wherein if x equals zero, y is a number less than 1/2.

Abstract: The invention provides non-antimony containing polymerization catalysts for the condensation of polyesters. The catalyst is in the form of a clear chlorine and/or bromine containing solution of a metal glycoxide and a metal glycolate having a pH in the range of from 0 to about 1, and containing chlorine and/or bromine atoms at a number ratio of chlorine and/or bromine to total metal cations in the catalyst ranging from about 0.5:1 to about 3:1. Polyesters produced with this catalyst have improved melt elasticity, and higher melt viscosity. The former property is desirable for the preparation of large and complex shaped polyester containers, and the latter property is desirable for melt spinning of industrial grade fibers and tire cords.

Abstract: Copolyether ester elastomers are provided which contain epoxide compounds. The compositions show improved bloom resistance in the presence of diamines with minimum increase in melt viscosity. Also disclosed are methods to improve appearance and eliminate bloom from finished products comprising thermoplastic copolyesters by lowering the level of acid terminated oligomers in the thermoplastic copolyesters with epoxide compounds.

Abstract: An ethylene terephthalate/ethylene-2,6-naphthalene dicarboxylate copolymer comprising 2,6-naphthalenedicarboxylic acid in an amount of 5 to 20 mol % of the total of all dicarboxylic acid components. This copolymer contains Mn, Mg and Co derived from catalysts and P derived from a phosphorus compound as a stabilizer whose amount is controlled to a specific value and is suitable for use as a raw material for molding a bottle having good color (achromatic) and transparency.

Abstract: A thermoplastic resin composition comprises units represented by the amide formula (I): ##STR1## and the ester formula (II): ##STR2## wherein said amide units are present as a physical mixture in said resin or as a polymer with the repeating ester units to impart an enhanced crystallization rate as compared to said resin without said amide units of formula (I), said amide units being present in an effective amount to decrease the difference between the temperature of melting and the temperature of crystallization of said resin to an amount less than 5 mole percent of amide unites of formula (I) based on the moles of ester units of formula (II).

Abstract: A method for making a polyester resin comprises reacting a first polyfunctional alcohol or polyfunctional thiol and a carbonate in the presence of a catalyst to form an alkoxylated intermediate. The catalyst comprises: (1) a metal, a salt of a metal, or mixtures thereof and (2) a quaternary ammonium salt, a tertiary amine, an imidazole, or mixtures thereof. The alkoxylated intermediate is then reacted with a polyfunctional organic acid or anhydride thereof to form the polyester resin.

Abstract: There is disclosed a method of manufacturing a polyester-series photographic support, comprising the steps of: incorporating at least one anthraquinone-series dye into a polyester, which polyester is produced by a condensation polymerization reaction of a dicarboxylic acid component that comprises a dialkyl ester of naphthalene-2,6-dicarboxylic acid as a main component, with a diol component that comprises ethylene glycol as a main component, the polyester being produced by allowing manganese, magnesium, antimony, and phosphorus to be incorporated in specific amounts, whereby the polyester has melt electric resistance in terms of common logarithm (log R) in the melt state at 300.degree. C. in the range of from 7.0 to 9.5, and intrinsic viscosity, measured in a mixture solution of phenol/tetrachloroethane (6/4, weight ratio) at 25.degree. C., in the range of from 0.49 to 0.

Abstract: The invention relates to a copolyester, having (a) a repeat unit of a dicarboxylic acid component, having from 80 to 100 mole % terephthalic acid or the corresponding ester thereof, and from 0 to 20 mole % of a modifying aromatic dicarboxylic acid having less than or equal to 20 carbon atoms or the corresponding ester thereof, wherein the total mole % of dicarboxylic acid component is equal to 100 mole %; and (b) a repeat unit of a glycol component, having from 5 to 85 mole % 2,2,4,4-tetramethyl-1,3-cyclobutanediol, ethylene glycol of from 15 to 95 mole %, and at least 1 mole % of a modifying glycol having from 3 to 16 carbon atoms, wherein the total mole % of glycol component is equal to 100 mole %. The invention also relates to a method of making the copolyester described above. The invention also relates to articles made from the copolyesters described above. The invention further relates to a method of determining the melt strength and sag of a polyester.

Abstract: A film-formable high molecular polyetherpolyester comprising structural unit (1) of formula (1) and functional group (2) of formula (2) and having a number-average molecular weight of 40,000 to 10,000,000, wherein the molar ratio of functional group (2) to R in the polyetherpolyester is in the range of 1.0 to 3.0. This polyetherpolyester can be produced by carrying out a chain extension reaction of a low molecular polyalkylene oxide of 1,000 to 30,000 in number-average molecular weight with a polyvalent acid anhydride at 0.003 MPa or higher in a molar ratio of (acid anhydride group)/(hydroxyl group)=0.8 to 1.0.

Abstract: A process for the preparation of an esterification product comprises reacting a polyfunctional organic acid or anhydride and a cyclic organic carbonate compound in the presence of a catalyst to form an esterification product. The catalyst comprises a quaternary ammonium salt and a component selected from the group consisting of a metal, a salt of a metal, and mixtures thereof.

Abstract: A polyester film made from a polymer having ethylene glycol moieties, isosorbide moieties and terepthaloyl moieties, and the method of making the film is described. The polyester film is used to form articles such as films, lacquers, labels, capacitors, insulators, and the like, and has an inherent viscosity of at least 0.35 dL/g when measured as a 1% (weight/volume) solution of the polyester in o-chlorophenol at a temperature of 25.degree. C.

Abstract: A general approach to making water-resistant polyetherester resins and thermosets is disclosed. In one aspect, an unsaturated polyetherester resin prepared by inserting a carboxylic acid derivative into a polyether is co-cured with a vinyl monomer and a di- or polyisocyanate to give a water-resistant, thermoset that has excellent dimensional stability, flexibility, and strength properties. Processes for making low-viscosity resins that give thermosets with good water resistance are also described. In one process, an unsaturated polyetherester resin intermediate reacts with a mono-functional isocyanate or fatty alcohol to produce an easy-to-formulate, low-viscosity, low-molecular-weight capped resin.

Abstract: A biaxially stretched polyester film for forming a container, characterized by being formed of a polyester substantially consisting of an ethylene terephthalate unit and an ethylene naphthalate unit, the refractive index in the direction of thickness of the film being 1.5 or greater. This film is not only excellent in the formability during formation into cans or the like, but has excellent properties in taste property, particularly, the taste property after the retorting, and may be suitably used for containers produced by forming process and, particularly, for metallic cans.

Abstract: The present invention relates to a process comprising polymerizing repeat units derived from an acid component comprising terephthalic acid and naphthalenedicarboxylic acid and at least one glycol in the presence of less than about 10 ppm sodium carbonate and between about 10 and about 60 ppm phosphorus. Polyesters formed via the process of the present invention display surprisingly good clarity and color.

Abstract: The invention relates to a preparation process of aliphatic polyester, comprising using an ion exchange resin as a drying agent and after the dehydration polycondensation reaction, regenerating and drying the used ion exchange resin and repeatedly using said ion exchange resin in the next dehydration polycondensation reaction, in a process for preparing aliphatic polyester from one or more aliphatic compound (A) by heating in an organic solvent in the presence of a catalyst, distilling a generated water containing organic solvent out of the reaction system, treating the distilled organic solvent with a drying agent, and returning the treated solvent to the reaction system to progress a dehydration polycondensation reaction. The process of the invention enables one to steadily and efficiently prepare in industry an aliphatic polyester having an excellent color tone, high molecular weight and high quality.

Abstract: A continuous process for producing polyethylene terephthalate polyester from terephthalic acid and ethylene glycol uses a stabilizer, preferably containing phosphorous, to produce a high quality polyethylene terephthalate polyester which is relatively free of the acetaldehyde and discoloration which are associated with the post-polymerization activity of a polymerization catalyst. The stabilizer is preferably added at or after the end of the polymerization reaction prior to polymer processing to deactivate the polymerization catalyst and can increase the throughput of the polyester without adversely affecting the thermal stability of the polyethylene terephthalate polyester. Alternatively, the late addition of the stabilizer can increase the thermal stability of the polyester without adversely affecting the throughput of the polyethylene terephthalate polyester.

Abstract: A process for making a random polyalkylene terephthalate/naphthalate copolymer by synthesizing a bis-(hydroxyalkyl)-naphthalate composition under transesterification conditions, and subsequently combining the bis-(hydroxyalkyl)-naphthalate, a terephthalic acid, and an alkylene glycol under direct esterification conditions to form a random polyaklylene terephthalate/naphthalate copolymer. The preferred bis-(hydroxyalkyl)-naphthalate is bis-(2-hydroxyalkyl)-2,6-naphthalate, with bis-(2-hydroxyethyl)-2,6-naphthalate being the most preferred. Preferably, the bis-(hydroxyalkyl)-naphthalate is added at the initial stage of an acid-based polymer process, and polymerization is initiated or continued to produce a polyester copolymer. Alternatively, the bis-(hydroxyalkyl)-naphthalate is added to phthalate-based oligomers after the initial direct esterification stage, and polymerization is continued to produce a polyester copolymer.

Abstract: The invention relates to Amorphous and/or semicrystalline copolyesters containing .beta.-hydroxyalkylamide groups according to formula (I) ##STR1## whereinP=polymer chain of the polyesterR1=alkyl residues with 1-5 atoms or hydrogen or ##STR2## R2=alkyl residues with 1-5 C-atoms or hydrogen, R3=alkyl residues and 1-5 C-atoms or hydrogen, andn.gtoreq.2,with a molecular weight (Mn) of 300 to 15,000 and a hydroxyl value of 10 to 400 ?mg KOH/g!.

Abstract: This invention relates to a process of producing a moldable polyethylene terephthalate or modified polyethylene terephthalate having an inherent viscosity greater than 0.6 dL/g comprising reacting the diacid component with the diol component such that a combination of a titanium-based catalyst and a phosphorus-based catalyst is used during the polycondensation steps.

Abstract: A process for making polyetherester resins is disclosed. A glycol ester of an aromatic diacid such as terephthalic acid is reacted with a polyether and a source of a dicarboxylic acid such as maleic anhydride to produce a polyetherester resin, wherein the aromatic diester content may be conveniently adjusted as desired. The process permits the preparation of unsaturated polyetherester resins with relatively high levels of terephthalate repeating units while avoiding the difficulties associated with the direct use of terephthalic acid in previously known procedures. Such unsaturated polyetheresters are useful for making thermoset resins with excellent mechanical and physical properties.

Abstract: A container formed from a copolyester composition which comprises a copolyester containing 80 to 95 mol % of terephthalic acid and 20 to 5 mol % of 2,6-naphthalenedicarboxylic acid as acid components and ethylene glycol as a glycol component, wherein catalyst metals of a calcium compound, magnesium compound and cobalt compound are contained in the copolyester in such amounts that satisfy all the following expressions (1) to (4) based on the total of the whole acid component of the polymer:0<Ca.ltoreq.35(mmol %) (1)0<Mg.ltoreq.80(mmol %) (2)40.ltoreq.(Mg+Ca).ltoreq.90(mmol %) (3)0.ltoreq.Co.ltoreq.15(mmol %) (4).The above polyester container is excellent in gas barrier property, ultraviolet light screening property, hot water resistance, hue and transparency, is not whitened and has a small content of aldehyde.

Abstract: A polyester comprises a dicarboxylic acid moiety comprising terephthalic acid or its ester forming derivative and a diol moiety comprising ethylene glycol and 1,4-cyclohexanedimethanol of 10 to 60 mol % based on the whole diol moiety, the intrinsic viscosity of the polyester being 0.68 to 0.95 dl/g, the "b" value of color tone of the produced pellets of polyester being -5 to 5, the number of the carboxylic acid terminals being not more than 30 eq/ton, and the sum of the numbers of the vinyl terminals, the vinylidene terminals and the methylcyclohexene terminals being not more than 25 eq/ton.

Abstract: A process for preparing a thermoplastic hydroxy-functionalized polyesters comprises contacting a dicarboxylic acid or a mixture of dicarboxylic acids with a diepoxide in the presence of a monofunctional carboxylic acid and a catalyst, and in the absence of a solvent under conditions sufficient to form the hydroxy-functionalized polyesters.

Abstract: New compounds including bis-.beta.-hydroxy ethyl bibenzoate containing less than 2.5%, and preferably less than 1%, diethylene glycol and a process for the production of the bis-.beta.-hydroxy ethyl bibenzoate by the condensation of 4,4'-biphenyl dicarboxylic acid and ethylene glycol at low temperature and pressure in the presence of a catalyst are disclosed. Use of the compounds to produce polyesters is also disclosed.

Abstract: The invention relates to heat-curable coating compounds containing a carboxyl-functional polyester produced by a condensation reaction from aliphatic and/or cycloaliphatic and/or aromatic polycarboxylic acids and anhydrides, a .beta.-hydroxyalkylamide and special stabilizers.

Abstract: A process for the preparation of a readily hydrolyzable and/or biodegradable polyhydroxycarboxylic acid resin which can be used in agricultural materials, gardening materials, fishery materials, caking materials, medical instruments and materials, etc. and, even when discarded after use, which undergoes hydrolysis and/or is biodegraded into carbon dioxide, water, etc. Also disclosed are a hydrolyzable and/or biodegradable polyhydroxycarboxylic acid resin composition having an increased resin strength and melt viscosity, and a process for the preparation thereof.

Abstract: New polyester composition for new polyester staple fiber that provides fabrics having a combination of excellent pilling performance, aesthetics and tactility ("hand"). Preferred fibers have non-round cross-sections that are retained, especially such non-round cross-sections having multi-grooved scalloped-oval cross-sections that provide fabrics having outstanding comfort qualities of moisture-management, dryness and comfort, along with minimal pilling.

Abstract: In the production of polyethylene naphthalate of the present invention, the esterification reaction between naphthalenedicarboxylic acid and ethylene glycol is conducted while causing water to be present in a reaction system from a start of reaction, in the presence of at least one catalyst selected from the group consisting of nitric, carboxylic, phosphoric and hydrogenphosphoric acid metal salts and alkyl amines according to necessity, to thereby attain an esterification ratio of 45 to 80%, so that a liquid mixture of naphthalenedicarboxylic acid esterification reaction products containing naphthalenedicarboxylic acid, carboxyl-hydroxyethoxycarbonylnaphthalene and bis(hydroxyethoxycarbonyl)naphthalene is obtained. Subsequently, a crystallized reaction product is separated from this liquid mixture to thereby obtain a mixture of esterification reaction products. Thereafter, this mixture having ethylene glycol added thereto according to necessity is subjected to polycondensation.

Abstract: The present invention is a packaging material composed of a thermoplastic polyester as a constituent material. By adjusting the contents of a dibasic carboxylic acid and its oligomer derived from the polyester to 500 ppm or less, and adjusting sodium to 6 ppm or less and all alkali metals to 30 ppm or less, especially 20 ppm or less, the flavor retention of the packaging material can be markedly increased.