Abstract: An object of the present invention is to provide a polyester resin excellent in moldability, surface smoothness, transparency, mechanical characteristics, and heat-resistance, with reduced generation of gel. The present invention relates to a polyester resin comprising a constituent moiety derived from dicarboxylic acid component and a constituent moiety derived from alcohol component, wherein a content of a compound represented by Formula (I) is 0.0002 to 5.9% by weight in 100% by weight of the alcohol component. In the Formula (I), m and n each represent 1 to 1000, 1 represents 0 to 1000, R1 represents an aromatic hydrocarbon group having 6 to 20 carbon atoms, and R2, R3, and R4 each represent a hydrogen atom or an alkyl group having 1 to 10 carbon atoms.

Abstract: The aim of the present invention is to provide a copolymerized polyester resin for solving the problem of die staining and foreign matter adhesion to the film etc. in the continuous production of the film etc.; and the problem of recycling property of the copolymerized polyester. This copolymerized polyester resin contains dicarboxylic acid and did as constituting components, wherein the copolymerized polyester resin contains terephthalic acid as a main component of a dicarboxylic acid component, and contains ethylene glycol as a main component of a diol component, wherein a content of diethylene glycol is from 7 to 30% by mole and a content of triethylene glycol is from 0.05 to 2% by mole when a total amount of the whole diol component is taken as 100% by mole, wherein a content of a cyclic dimer consisting of terephthalic acid and diethylene glycol is 7000 ppm or less, and wherein a content of a cyclic dimer consisting of terephthalic acid, diethylene glycol and triethylene glycol is 200 ppm or less.

Abstract: The invention provides a copolymerized polyester resin which contains terephthalic acid as a main component of a dicarboxylic acid component; and contains ethylene glycol as a main component of a diol component, wherein a content of neopentyl glycol is more than 15% by mole and not more than 40% by mole and a content of diethylene glycol is from 6 to 20% by mole when a total amount of the whole diol component is taken as 100% by mole, wherein a content of a cyclic dimer consisting of terephthalic acid, neopentyl glycol and diethylene glycol is 5000 ppm or less, and wherein a content of a cyclic trimer consisting of terephthalic acid and ethylene glycol is 5000 ppm or less.

Abstract: Provided is a hydrolysis-resistant polyester film having a low acid value due to suppression of acid value-increase during film formation. The hydrolysis-resistant polyester film of the present invention is a polyester film comprising a polyester resin composition, wherein the polyester resin composition that forms the films comprises 0.03 to 6.7 eq/ton of hindered phenol structural units, an acid value of a polyester that forms the film is less than 25 eq/ton, and an intrinsic viscosity of a polyester that forms the film is more than 0.64 dL/g and not less than 0.90 dL/g.

Abstract: The present invention is directed to a heat-resistant polyester blow-molded article made of a polyester resin composition containing 0.035 to 1.75 equivalent/ton of a hindered phenol structural unit and containing at least one selected from the group consisting of antimony compounds as a polymerization catalyst, the cyclic trimer content thereof being less than or equal to 0.5% by mass, the acetaldehyde content thereof being less than or equal to 50 ppm and the intrinsic viscosity thereof being 0.68 to 0.90 dL/g. The present invention enables efficient production of a molded article excellent in transparency and heat-resistant dimensional stability, in particular a heat-resistant blow-molded article. Moreover, according to the present invention, there are provided a polyester resin composition which is excellent in long-term continuous moldability and hardly stains a mold and a molded article prepared therewith, and a method for molding a polyester blow-molded article using the polyester resin composition.

Abstract: The present invention is directed to a heat-resistant polyester blow-molded article made of a polyester resin composition containing 0.035 to 1.75 equivalent/ton of a hindered phenol structural unit and containing at least one selected from the group consisting of antimony compounds as a polymerization catalyst, the cyclic trimer content thereof being less than or equal to 0.5% by mass, the acetaldehyde content thereof being less than or equal to 50 ppm and the intrinsic viscosity thereof being 0.68 to 0.90 dL/g. The present invention enables efficient production of a molded article excellent in transparency and heat-resistant dimensional stability, in particular a heat-resistant blow-molded article. Moreover, according to the present invention, there are provided a polyester resin composition which is excellent in long-term continuous moldability and hardly stains a mold and a molded article prepared therewith, and a method for molding a polyester blow-molded article using the polyester resin composition.

Abstract: The present invention provides a polyester resin obtained by using an aluminum compound and a phosphorus compound as a polymerization catalyst, containing greater than or equal to 85% by mol of an ethylene terephthalate structural unit, wherein the content of an aluminum-based contaminant with respect to the mass of the polyester resin is less than or equal to 100 ppb, and the content of a phosphorus compound represented by a specific structure is 5 to 11 ppm. The present invention is able to provide a polyester resin capable of keeping high transparency of the molded body when it is sequentially polymerized and produced on a commercial scale, and having such characteristics that crystallization of a mouth plug part can be easily controlled when it is used for a heat resistant bottle, and whitening is less likely to occur at the time of heating in molding when it is used as a sheet for molding.

Abstract: Provided is a hydrolysis-resistant polyester film having a low acid value due to suppression of acid value-increase during film formation. The hydrolysis-resistant polyester film of the present invention is a polyester film comprising a polyester resin composition, wherein the polyester resin composition that forms the films comprises 0.03 to 6.7 eq/ton of hindered phenol structural units, an acid value of a polyester that forms the film is less than 25 eq/ton, and an intrinsic viscosity of a polyester that forms the film is more than 0.64 dL/g and not less than 0.90 dL/g.

Abstract: A polyester composition comprising 99.9 to 80 wt % of a thermoplastic polyester containing an antimony compound and 0.1 to 20 wt % of a partially aromatic polyamide, wherein a 4 mm-thick molded plate formed by molding the thermoplastic polyester at 290° C. has a haze value of 10% or lower, and wherein the phosphorus atom content in the partially aromatic polyamide (P1), the partially aromatic polyamide content in the polyester composition (A), and the antimony atom content in the thermoplastic polyester (S) satisfy a specific formula, wherein a 4 mm-thick molded plate produced by molding the polyester composition at 290° C. has a haze value of 20% or lower. The polyester composition can be molded into a hollow molded article (e.g., a bottle) at a high productivity rate, which is not deteriorated in transparency or color, and which is excellent in flavor-conserving property, thermal stability and gas-barrier property.

Abstract: A polyester resin that can be beneficially employed as one finding application in deactivation of polycondensation catalysts for polyester production and suppression of forming of acetaldehyde and other aldehydes and cyclic ester oligomers at molding stage. In particular, there is provided a polyester resin composed mainly of an aromatic dicarboxylic acid component and a glycol component wherein a phosphorus compound is incorporated through copolymerization or blending in an amount of 100 to 10,000 ppm in terms of phosphorus element, characterized in that the contents of Zn element, Fe element, Ni element and Cr element are not greater than specified values.

Abstract: The invention is a polyester resin mainly comprising a terephthalic acid component and a glycol component, wherein the fluorescence spectrum obtained by irradiating the polyester resin with excited light having a wavelength of 343 nm has a fluorescence intensity at 450 nm (B0) of 20 or lower. The resin makes it possible to efficiently produce a shaped article, especially a heat-resistant blow-molded article, that has excellent transparency and a moderate and stable crystallization rate and excellent heat-resistance dimensional stability, and is prevented from emitting fluorescence when irradiated with UV rays, and which is excellent in long-run continuous workability with no mold contamination, and which provides a wrapping material having excellent flavor retentiveness.

Abstract: A coat resin composition comprising a polyester (A) comprising an acid component comprising an aromatic dicarboxylic acid in a proportion of 50-100% by mole relative to the entire acid component and other carboxylic acid(s) in a proportion of 50-0% by mole relative to the entire acid component, and a glycol component comprising 2-methyl-1,3-propanediol and/or 1,3-propanediol in a proportion of 1-25% by mole relative to the entire glycol component and an alkylene glycol having 5 to 10 carbon atoms in a proportion of 75-99% by mole relative to the entire glycol component, or an alicyclic glycol in a proportion of 20-85% by mole relative to the entire glycol component, an addition product of bisphenol A with alkylene oxide in a proportion of 80-15% by mole relative to the entire glycol component and other glycol(s) in a proportion of 0-50% by mole relative to the entire glycol component, wherein the total of the glycols is 100% by mole, the polyester (A) having a reduced viscosity of not less than 0.

Abstract: An aqueous dispersion comprising (A) a polyester comprising an aromatic dicarboxylic acid, an addition product of bisphenol A with ethylene oxide and/or propylene oxide, and a dicarboxylic acid having a metal base of sulfonic acid and/or a polyol having a metal base of sulfonic acid, (B) a water-soluble organic compound having a boiling temperature of about 60.degree. C. to about 250.degree. C., (C) water and (D) a neutralizer; the amounts of the components A, B, C and D satisfying the following ratios of (1) to (3):(1) A/B/C being about 1% to about 70% by weight/about 0% to about 69% by weight/about 9% to about 99% by weight,(2) B/(B+C) being about 0 to about 0.7 (weight ratio), and(3) the equivalent ratio of D to A being about 0.1 to about 20.

Abstract: An aqueous dispersion suitable for use as various coatings is provided. The dispersion includes polyester resin (A), a water soluble organic compound (B), water (C), and a neutralizer (D). The polyester resin has an acid number of 50 equivalents/10.sup.6 g or more. The polycarboxylic acid component of the resin contains aromatic dicarboxylic acid having no metal sulfonate groups in an amount in the range of 50 to 99.99 mole percent, and dicarboxylic acid having a metal sulfonate group in an amount in the range of 0.01 to 20 mole percent based on the total moles of the polycarboxylic acid component. The polyol component of the resin contains diol in an amount in the range of 30 to 100 mole percent based on the total moles of the polyol component. The diol has an alkyl group with 1 to 3 carbon atoms on a side chain, and the total number of carbon atoms in the diol is 6 to 25. The water soluble organic compound has a boiling point in the range of 60.degree. to 250.degree. C.