Coating solution for gas barrier, gas barrier laminate, packaging material and packaging material for heat sterilization

Patent metadata

Field	Value
Publication number	US-11279844-B2
Application number	US-201916708041-A
Country	US
Kind code	B2
Filing date	Dec 9, 2019
Priority date	Nov 7, 2012
Publication date	Mar 22, 2022
Grant date	Mar 22, 2022

Abstract

This coating solution for a gas barrier contains an ammonium salt (A) of a polymer having a carboxyl group, a particulate multivalent metallic compound (B), and water, the content of the multivalent metallic compound (B) being about 0.5-2.0 times the chemical equivalent of the ammonium salt (A), and the mean particle diameter of the multivalent metallic compound (B) being about 4 μm or less.

First claim

What is claimed is:

1. A method of preparing a coating solution for a gas barrier, consisting of:
preparing a mixture consisting of an ammonium salt of a polymer that includes carboxylic groups (A), a particulate multivalent metallic compound (B) and a solvent that consists of water and an alcohol, wherein an amount of the particulate multivalent metallic compound in the mixture is 0.5 times to 2.0 times the chemical equivalent of the ammonium salt of the polymer (A); and
performing a dispersion treatment of the prepared mixture so that after the treatment a mean particle size of the multivalent metallic compound (B) is 4 μm or less and 50 nm or more to form the coating solution.

2. The method of claim 1 , wherein the dispersion treatment is performed using a ball mill or a bead mill having a diameter of treatment balls or beads of 0.2 to 1 mm.

3. The method of claim 1 , wherein the multivalent metallic compound (B) is at least one selected from the group consisting of an oxide, hydroxide and carbonate of a multivalent metal selected from the group consisting of zinc, magnesium and calcium.

4. The method of claim 1 , wherein the multivalent metallic compound (B) is at least one selected from the group consisting of zinc oxide and magnesium oxide.

5. The method of claim 1 , wherein the polymer including a carboxyl group is polyacrylic acid.

6. The method of claim 1 , wherein the multivalent metallic compound has a solubility of 5.0 g or less at 25° C. in 1 L of water and the ammonium salt (A) is 1.5 mass % to 10 mass % relative to a gross mass of the coating solution, and
a pH of the coating solution is 6.5-9.5 at 25° C.

7. A method of producing a gas barrier laminate comprising a substrate and a gas barrier layer provided on at least one surface of the substrate,
wherein the gas barrier layer includes a coat layer, wherein the method consists of: preparing a mixture consisting of an ammonium salt of a polymer that includes carboxylic groups (A), a particulate multivalent metallic compound (B) and a solvent that consists of water and an alcohol, wherein an amount of the particulate multivalent metallic compound in the mixture is 0.5 times to 2.0 times the chemical equivalent of the ammonium salt of the polymer (A);
performing a dispersion treatment of the prepared mixture so that after the treatment a mean particle size of the multivalent metallic compound (B) is 4 μm or less and 50 nm or more to form a coating solution;
and forming the coat layer by applying the coating solution on the substrate and then drying.

8. The method of claim 7 , wherein the drying is performed at a temperature of 40 to 150° C. in an oven.

9. The method of claim 8 , wherein the drying is performed for 0.5 seconds to 10 minutes.

10. The method of claim 7 , wherein the drying is performed for 0.5 seconds to 10 minutes.

Assignees

• Toppan Printing Co Ltd

Inventors

• Oto Chisato
• Kawaguchi Katsumi

Classifications

• C09D133/02 Primary

  Homopolymers or copolymers of acids; Metal or ammonium salts thereof · CPC title

• B32B27/00

  Layered products comprising {a layer of} synthetic resin {(fibrous or filamentary layer made of a synthetic resin B32B5/02; particulate layer made of a synthetic resin B32B5/16; foamed layer made of a synthetic resin B32B5/18)} · CPC title

• C09D7/61

  inorganic · CPC title

• C08K3/26

  Carbonates; Bicarbonates · CPC title

• C09D5/00

  Coating compositions, e.g. paints, varnishes or lacquers, characterised by their physical nature or the effects produced {(electrically insulating plastics, resins or waxes H01B3/30)}; Filling pastes · CPC title