Method for reproducing polyester container and reproduced polyester chip prepared therefrom

Patent metadata

Field	Value
Publication number	US-11008435-B2
Application number	US-201916687388-A
Country	US
Kind code	B2
Filing date	Nov 18, 2019
Priority date	Apr 30, 2018
Publication date	May 18, 2021
Grant date	May 18, 2021

Abstract

Embodiments relate to a process for regenerating a polyester container and regenerated polyester chips prepared therefrom. The process comprises preparing a polyester container provided with a heat shrinkable film; crushing the container provided with the heat shrinkable film to obtain flakes; and thermally treating the flakes to produce regenerated polyester chips, wherein when the flakes are thermally treated at a temperature of 200° C. to 220° C. for 60 minutes to 120 minutes, the clumping fraction is 5% or less, and the flakes comprise first flakes obtained by crushing the container and second flakes obtained by crushing the heat shrinkable film. It not only solves the environmental problems by improving the recyclability of the polyester container, but also is capable of enhancing the yield and productivity.

First claim

The invention claimed is:

1. A plastic container comprising:
a polyester container, and
a heat shrinkable film, which is provided at the polyester container;
wherein the heat shrinkable film is shrunk by steam or hot air to wrap the outer surface of the polyester container,
wherein the heat shrinkable film comprises a copolymerized polyester resin comprising a diol component and a dicarboxylic acid component and
has a heat shrinkage rate of 30% or more in the main shrinkage direction upon thermal treatment at a temperature of 80° C. for 10 seconds and
a melting point of 190° C. or higher as measured by differential scanning calorimetry,
wherein when a plurality of flakes are thermally treated at a temperature of 200° C. to 220° C. for 60 minutes to 120 minutes, the clumping fraction is 5% or less,
wherein the flakes comprise first flakes obtained by crushing the container and second flakes obtained by crushing the heat shrinkable film.

2. The plastic container of claim 1 , wherein the copolymerized polyester resin comprises ethylene glycol and neopentyl glycol.

3. The plastic container of claim 1 , wherein the particle size of the first flakes is 0.1 to 20 mm, and the particle size of the second flakes is 0.1 to 20 mm.

4. The plastic container of claim 1 , wherein the polyester container comprises polyethylene terephthalate in an amount of 90% by weight or more.

5. The plastic container of claim 1 , wherein the copolymerized polyester resin comprises neopentyl glycol in an amount of 5 to 35% by mole based on the total number of moles of the diol component and terephthalate in an amount of at least 90% by mole based on the total number of moles of the dicarboxylic acid component.

6. The plastic container of claim 1 , wherein the copolymerized polyester resin comprises ethylene glycol in an amount of 55 to 93% by mole and diethylene glycol in an amount of 2 to 10% by mole based on the total number of moles of the diol component.

7. The plastic container of claim 1 , wherein the heat shrinkable film has a melting point of 190° C. or higher as measured by differential scanning calorimetry.

8. The plastic container of claim 1 , wherein the crystallization temperature of the heat shrinkable film is not measured or is 70° C. to 95° C. by differential scanning calorimetry.

Assignees

• Skc Inc
• Skc Co Ltd

Inventors

• Shin Daeyong
• Kim Yongdeuk
• Lee Jung Kyu
• Son Jaehyong
• Jung Eugene

Classifications

• Y02W30/62

  Plastics recycling; Rubber recycling · CPC title

• C08G63/672 Primary

  Dicarboxylic acids and dihydroxy compounds · CPC title

• C08G63/183

  Terephthalic acids · CPC title

• B29B2017/0468

  Crushing, i.e. disintegrating into small particles · CPC title

• C08J5/18

  Manufacture of films or sheets · CPC title