Thermoplastic polyester composition having improved flavor-retaining property and vessel formed therefrom

• US 4,837,115 A
• Filed: 07/30/1987
• Issued: 06/06/1989
• Est. Priority Date: 07/30/1986
• Status: Expired due to Term

• Current Assignee: TOYO Seikan Kaisha Limited
• Original Assignee: TOYO Seikan Kaisha Limited
• Inventors: Igarashi, Reiko, Watanabe, Yoshihiko, Hirata, Sadao
• Primary Examiner(s): Robinson, Ellis P.
• Assistant Examiner(s): Seidleck, James J.
• Application Number:
  US07/079,387
• Time in Patent Office: 677 Days
• Field of Search: 428/35, 428/474.4, 428/475.2, 428/480, 525/425, 264/523
• US Class Current: 428/36.92
• CPC Class Codes: B29C 2049/7879 Stretching, e.g. stretch rod
• CPC Class Codes: B29C 2949/22 at neck portion
• CPC Class Codes: B29C 2949/24 at flange portion
• CPC Class Codes: B29C 2949/26 at body portion
• CPC Class Codes: B29C 2949/28 at bottom portion
• CPC Class Codes: B29C 2949/3008 at neck portion
• CPC Class Codes: B29C 2949/3012 at flange portion
• CPC Class Codes: B29C 2949/3016 at body portion
• CPC Class Codes: B29C 2949/302 at bottom portion
• CPC Class Codes: B29C 2949/3024 characterised by the number of components or by the manufacturing technique
• CPC Class Codes: B29C 2949/3028 having three or more components
• CPC Class Codes: B29C 2949/3032 having components being injected
• CPC Class Codes: B29C 2949/3036 having three or more components being injected
• CPC Class Codes: B29C 2949/3041 having components being extruded
• CPC Class Codes: B29C 2949/3056 having components being compression moulded
• CPC Class Codes: B29C 49/0005 characterised by the material
• CPC Class Codes: B29C 49/087 Means for providing controlled or limited stretch ratio
• CPC Class Codes: B29K 2067/00 Use of polyesters or derivatives thereof, as moulding material
• CPC Class Codes: B29K 2105/0002 monomers or prepolymers
• CPC Class Codes: B65D 1/0215 multilayered B65D81/3837 takes precedence
• CPC Class Codes: C08L 67/02 : Polyesters derived from dicarboxylic acids and dihydroxy compounds C08L67/06 takes precedence
• CPC Class Codes: C08L 77/08 : from polyamines and polymerised unsaturated fatty acids
• CPC Class Codes: Y10T 428/1397 : Single layer [continuous layer]
• CPC Class Codes: Y10T 428/31725 : Of polyamide
• CPC Class Codes: Y10T 428/31736 : Next to polyester
• CPC Class Codes: Y10T 428/31786 : Of polyester [e.g., alkyd, etc.]

Abstract

In a vessel composed of a thermoplastic polyester such as polyethylene terephthalate, by incorporating a predetermined amount of a terminal amino group-containing polyamide or an amino group-containing compound into the polyester, acetaldehyde formed in the vessel wall can be effectively caught.

Claims

1. A heat-molded or draw-formed plastic vessel composed of a thermoplastic polyester composition comprising (A) a thermoplastic polyester having ethylene terephthalate units and (B) 3×

10^-7 to 10.0% by weight, based on the polyester, of a thermoplastic polyamide having a terminal amino group at a concentration of 0.05 to 50 millimoles per 100 g of the resin, said thermoplastic polyamide being a polymerized fatty acid polyamide obtained by polycondensation of (i) a polymerized fatty acid formed by polymerizing an unsaturated fatty acid with (ii) a diamine.

2. A vessel as set forth in claim 1, wherein the thermoplastic polyester (A) is polyethylene terephthalate.

3. A vessel as set forth in claim 1, wherein the thermoplastic polyester (A) is a copolyester comprising in the polymer chain a terephthalic acid component and an isophthalic acid component at a molar ratio of from 95/5 to 5/95 and an ethylene glycol component and a bis(2-hydroxyethoxy)benzene component at a molar ratio of from 99.999/0.001 to 2.0/98.0.

4. A vessel as set forth in claim 1, wherein the polyamide (B) is incorporated in an amount of 5×

10^-7 to 10.0% by weight based on the thermoplastic polyester (A).

5. A vessel as set forth in claim 1, wherein the polyamide (B) is incorporated in an amount of 5×

10^-4 to 5.0% by weight based on the thermoplastic polyester (A).

6. A vessel as set forth in claim 1, wherein the terminal amino group concentration in the polyamide (B) is 0.1 to 40 millimoles per 100 g of the resin.

7. A vessel as set forth in claim 3, which is a multi-layer vessel comprising a layer of said thermoplastic polyester composition as a gas barrier layer.

8. A vessel as set forth in claim 7, which is obtained by forming a laminate having a layer of said thermoplastic polyester composition by co-injection molding and molding the laminate into a vessel.

9. A vessel as set forth in claim 1, wherein said polymerized fatty acid polyamide is a polyamide of dimerized linoleic acid with hexamethylene-diamine.

10. A polyester vessel having an improved flavor-retaining property, which is composed of a resin composition comprising (A) a thermoplastic polyester and (C) 5×

10^- to 3.0% by weight, based on the polyester, of a primary amino group-containing compound having a molecular weight of at least 100, said compound being selected from the group consisting of polyoxyethylene diamine, spiroacetal diamine and spiroguanamine.

11. A polyester vessel as set forth in claim 10, wherein the amino group-containing compound (C) is a compound having a molecular weight of at least 100 and containing a primary amino group at a concentration of 0.05 to 3000 meq/100 g.

12. A vessel as set forth in claim 10, wherein the thermoplastic polyester (A) is polyethylene terephthalate.

13. A vessel as set forth in claim 10, wherein the thermoplastic polyester (A) is a copolyester comprising in the polymer chain a terephthalic acid component and isophthalic acid component at a molar ratio of from 95/5 to 5/95 and an ethylene glycol component and a bis(2-hydroxyethoxy)benzene component at a molar ratio of from 99.999/0.001 to 2.0/98.0.

14. A polyester vessel as set forth in claim 13, which is a multi-layer vessel comprising a layer of said resin composition as a gas barrier layer.

15. A polyester vessel as set forth in claim 10, which is obtained by forming a laminate having a layer of said resin composition by co-injection molding and molding the laminate into a vessel.

16. A method for reducing the acetaldehyde concentration in a heat-molded polyester vessel, which comprises dry-blending a thermoplastic polyester with 3×

10^- to 10.0% by weight, based on the polyester, of a thermoplastic polyamide having a terminal amino group at a concentration of 0.05 to 50 millimoles per 100 g of the resin, melt-kneading the composition and thermoforming the melt-kneaded composition into a vessel, wherein said thermoplastic polyamide is a polymerized fatty acid polyamide obtained by polycondensation of (i) a polymerized fatty acid formed by polymerizing an unsaturated fatty acid with (ii) a diamine.

17. A method for reducing the acetaldehyde concentration in a heat-molded polyester vessel, which comprises dry-blending a thermoplastic polyester with 5×

10^-7 to 3.0% by weight, based on the polyester, of a primary amino group-containing compound having a molecular weight of at least 100, melt-kneading the composition and thermoforming the melt-kneaded composition into a vessel, wherein said compound is selected from the group consisting of polyoxyethylene diamine, spiroacetal diamine and spiroguanamine.