Heat sealable barrier coating

• US 11,555,276 B2
• Filed: 04/26/2018
• Issued: 01/17/2023
• Est. Priority Date: 04/28/2017
• Status: Active Grant

• Current Assignee: Sun Chemical Corporation
• Original Assignee: Sun Chemical Corporation
• Inventors: Triclot, Magali, Le Lain, Pierrick, Beche, Michel, Caron, Dominique, Turgis, Jean-Dominique
• Primary Examiner(s): Halpern, Mark
• Application Number:
  US16/607,458
• Publication Number:
  US 20200131708A1
• Time in Patent Office: 1,727 Days
• Field of Search: 428 342
• CPC Class Codes: B65D 5/563 Laminated linings; Coatings
• CPC Class Codes: B65D 65/42 Applications of coated or impregnated materials
• CPC Class Codes: C08L 23/06 Polyethene
• CPC Class Codes: C09D 133/08 Homopolymers or copolymers of acrylic acid esters
• CPC Class Codes: C09D 191/06 Waxes
• CPC Class Codes: D21H 19/18 comprising waxes
• CPC Class Codes: D21H 19/20 comprising macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
• CPC Class Codes: D21H 19/40 siliceous, e.g. clays
• CPC Class Codes: D21H 19/58 Polymers or oligomers of diolefins, aromatic vinyl monomers or unsaturated acids or derivatives thereof
• CPC Class Codes: D21H 21/16 Sizing or water-repelling agents
• CPC Class Codes: D21H 27/10 Packing paper packaging materials of special type or form B65D65/38

Abstract

The present invention provides a heat-sealable water-based coating composition suitable for coating substrates used for packaging of products that contain grease, oil, water, etc. The coating compositions comprise acrylic polymer or copolymer emulsions and melting waxes. The substrates may be formed into containers, such as cups, for example. The coatings provide a barrier that is resistant to the permeation of, for example, grease, oil, water, and other liquids. Furthermore, the coating compositions are compostable.

Claims

1. A heat sealable water-based coating composition comprising:

a) 5 wt % to 90 wt % one or more acrylic polymer or copolymer emulsions;

b) 2 wt % to 25 wt % one or more melting waxes;

c) 5 wt % to 85 wt % water; and

d) 0.01 wt % to 20 wt % one or more fillers;

wherein the heat sealable water-based coating composition is a single composition comprising all of items a, b, c, and d; and

wherein the heat sealable water-based coating composition is compostable.

2. The composition of claim 1, wherein the melting wax has a melting point of 40°

C. to 100°

C.

3. The composition of claim 1, wherein the one or more melting waxes are selected from the group consisting of paraffin wax, acrylic-grafted paraffin wax, crystalline wax, polyethylene wax, high density polyethylene wax, polyethylene/polytetrafluorethylene wax, carnauba wax, and combinations thereof;

and/or wherein the one or more acrylic polymer or copolymer emulsions are selected from the group consisting of pure acrylic polymer, ethylene acrylic acid copolymer, vinyl acrylic acid copolymer, styrene-acrylic copolymer, and combinations thereof.

4. The composition of claim 1, further comprising one or more additives selected from the group consisting of adhesion promoters, light stabilizers, de-gassing additives, flow promoters, defoamers, antioxidants, stabilizers, wetting agents, surfactants, clays, dispersants, plasticizers, rheological additives, other waxes, silicones, colorants, and combinations thereof.

5. The composition of claim 1, wherein the coating composition is a barrier coating composition, resistant to permeation of liquids and vapors.

6. The composition of claim 1, wherein the composition is recyclable, biodegradable, and compostable.

7. A substrate comprising the coating composition of claim 1.

8. The substrate of claim 7, which is cellulosic.

9. The substrate of claim 7, wherein the substrate is compostable;

and/or wherein the substrate is repulpable.

10. An article comprising the substrate of claim 7.