Polyethylene terephthalate resin composition and film formed from same

Patent metadata

Field	Value
Publication number	US-10774178-B2
Application number	US-201615771899-A
Country	US
Kind code	B2
Filing date	Oct 17, 2016
Priority date	Oct 29, 2015
Publication date	Sep 15, 2020
Grant date	Sep 15, 2020

Abstract

A polyethylene terephthalate resin composition which is characterized by having a manganese element content of 30 to 60 ppm, a potassium element content of 2 to 10 ppm, an antimony element content of 70 to 150 ppm, a molar ratio of metal elements to phosphorus element (M/P=(M1+M2/2)/P) satisfying formula (1), and a gelation ratio of 5% by weight or less:

0.6≤(M1+M2/2)/P≤1.3  (1)

wherein M1 represents the content (mol/t) of a bivalent metal element selected from the group consisting of Mg, Mn, and Ca; M2 represents the content (mol/t) of a monovalent metal element selected from the group consisting of Li, Na, and K; and P represents the content (mol/t) of phosphorus element.

First claim

The invention claimed is:

1. A polyethylene terephthalate resin composition, having a manganese element content of 30 to 60 ppm, a potassium element content of 2 to 10 ppm, and an antimony element content of 70 to 150 ppm with respect to the total weight of elements of the polyethylene terephthalate resin composition,
wherein a molar ratio of metal elements to phosphorus element, (M/P=(M1+M2/2)/P), satisfies formula (1):
0.6≤(M1+M2/2)/P≤1.3  (1)

wherein M1 represents the content (mol/t) of Mn and, optionally, at least one of a bivalent metal element selected from the group consisting of Mg and Ca;
M2 represents the content (mol/t) of a monovalent metal element selected from the group consisting of Li and K; and
P represents the content (mol/t) of phosphorus element;
the total content of metal elements: Mg, Ca, and Li is less than 0.1 ppm;
the content of phosphorus element is 15 ppm to 45 ppm; and
the composition has a gelation ratio of 5% by weight or less.

2. The polyethylene terephthalate resin composition according to claim 1 , wherein the composition generates linear oligomer in an amount of 210 μg/g or less when melted at 290° C. for 20 minutes.

3. The polyethylene terephthalate resin composition according to claim 1 , wherein the composition comprises internal particles whose largest particle diameter is 0.3 μm or less, and has 1.0% or less of solution haze.

4. The polyethylene terephthalate resin composition according to claim 1 , having a COOH terminal group content of 25 to 40 eq/t, wherein the COOH terminal group amount (ΔCOOH) increases after heat-moisture treatment by 80 eq/t or less.

5. The polyethylene terephthalate resin composition according to claim 1 , having an intrinsic viscosity of 0.60 to 0.70, a COOH terminal group content of 5 to 20 eq/t, and 0.40% by weight or less of cyclic trimeric oligomer.

6. A polyester film formed from the polyethylene terephthalate resin composition according to claim 1 .

Assignees

• Toray Industries

Inventors

• Fujiwara Susumu
• Sai Hiromitsu
• Yoshimura Hitoshi
• Kamigaito Yoshiki

Classifications

• C08G63/87

  Non-metals or inter-compounds thereof (boron C08G63/84) · CPC title

• C08J5/18

  Manufacture of films or sheets · CPC title

• C08K2003/026

  Phosphorus · CPC title

• C08L67/02 Primary

  Polyesters derived from dicarboxylic acids and dihydroxy compounds (C08L67/06 takes precedence) · CPC title

• C08G63/866

  Antimony or compounds thereof · CPC title