Packaging bag, and method using same for storing polyvinyl alcohol-based resin that contains modified group having active hydrogen

Patent metadata

Field	Value
Publication number	US-10518498-B2
Application number	US-201515512654-A
Country	US
Kind code	B2
Filing date	Sep 28, 2015
Priority date	Sep 30, 2014
Publication date	Dec 31, 2019
Grant date	Dec 31, 2019

Abstract

A packaging bag for packaging a polyvinyl alcohol-based resin that contains a modified group having active hydrogen, the packaging bag including a film having a water vapor permeability of 10 g/m 2 /day or less. Accordingly, when a polyvinyl alcohol-based resin that contains a modified group having active hydrogen is packaged with the packaging bag, the storage stability of the polyvinyl alcohol-based resin that contains a modified group having active hydrogen can be improved, and hence an aqueous solution of the polyvinyl alcohol-based resin that contains a modified group having active hydrogen, the solution being reduced in insoluble matter content, can be obtained even after long-term storage thereof.

First claim

The invention claimed is:

1. A method comprising packaging a polyvinyl alcohol-based resin that contains a modified group having active hydrogen within a packaging bag;
wherein the packaging bag comprises a film containing a low-density polyethylene and having a water vapor permeability of 10 g/m 2 /day or less; and
wherein the polyvinyl alcohol-based resin that contains a modified group having active hydrogen comprises a powdery matter having an average particle diameter of from 100 μm to 1,000 μm.

2. The method according to claim 1 , wherein the packaging bag includes only a water vapor barrier layer having a water vapor permeability of 10 g/m 2 /day or less.

3. The method according to claim 1 , wherein the packaging bag includes a multilayer structure film formed of a substrate film layer, a water vapor barrier layer, and a protective film layer.

4. The method according to claim 1 , wherein the packaging bag has a thickness of from 10 μm to 450 μm.

5. The method according to claim 1 , wherein the polyvinyl alcohol-based resin that contains a modified group having active hydrogen has an average polymerization degree in conformity with JIS K 6726 of from 200 to 4,000.

6. The method according to claim 1 , wherein the polyvinyl alcohol-based resin that contains a modified group having active hydrogen has a saponification degree in conformity with JIS K 6726 of from 80 mol % to 100 mol %.

7. The method according to claim 1 , wherein the polyvinyl alcohol-based resin that contains a modified group having active hydrogen comprises an acetoacetyl group-containing polyvinyl alcohol-based resin.

8. The method according to claim 1 , wherein the packaging bag further comprises kraft paper, the kraft paper being outside the film.

9. The method according to claim 1 , wherein the packaging bag is sheathed with a sheath bag comprising kraft paper.

10. A method of storing a polyvinyl alcohol-based resin that contains a modified group having active hydrogen, wherein the method comprises hermetically sealing a powdery matter of the polyvinyl alcohol-based resin that contains a modified group having active hydrogen with a packaging bag including a film containing a low-density polyethylene having a water vapor permeability of 10 g/m 2 /day or less; and
wherein the powdery matter of the polyvinyl alcohol-based resin that contains a modified group having active hydrogen has an average particle diameter of from 100 μm to 1,000 μm.

11. The method according to claim 10 , wherein the polyvinyl alcohol-based resin that contains a modified group having active hydrogen comprises an acetoacetyl group-containing polyvinyl alcohol-based resin.

12. The method according to claim 10 , wherein the packaging bag includes only a water vapor barrier layer having a water vapor permeability of 10 g/m 2 /day or less.

13. The method according to claim 10 , wherein the packaging bag includes a multilayer structure film formed of a substrate film layer, a water vapor barrier layer, and a protective film layer.

14. The method according to claim 10 , wherein the packaging bag has a thickness of from 10 μm to 450 μm.

15. The method according to claim 10 , wherein the polyvinyl alcohol-based resin that contains a modified group having active hydrogen has an average polymerization degree in conformity with JIS K 6726 of from 200 to 4,000.

16. The method according to claim 10 , wherein the polyvinyl alcohol-based resin that contains a modified group having active hydrogen has a saponification degree in conformity with JIS K 6726 of from 80 mol % to 100 mol %.

17. The method according to claim 10 , wherein the packaging bag further comprises kraft paper, the kraft paper being outside the film.

18. The method according to claim 10 , wherein the packaging bag is sheathed with a sheath bag comprising kraft paper.

Assignees

• Nippon Synthetic Chem Ind Co Ltd
• Mitsubishi Chem Corp

Inventors

• TAKAHASHI Hirosato
• Nishikawa Yukitoshi
• Fujii Tomoyuki

Classifications

• B65D65/42

  Applications of coated or impregnated materials · CPC title

• B32B15/09

  comprising polyesters · CPC title

• B32B15/088

  comprising polyamides · CPC title

• B32B15/085

  comprising polyolefins · CPC title

• B32B27/10

  of paper or cardboard · CPC title