Method of making and using a degradable package for containment of liquids

• US 5,512,333 A
• Filed: 04/06/1994
• Issued: 04/30/1996
• Est. Priority Date: 10/16/1992
• Status: Expired due to Fees

• Current Assignee: Confab, Inc. (Johnson Controls International plc)
• Original Assignee: ICD Industries
• Inventors: Suskind, Stuart P.
• Primary Examiner(s): Seidleck, James J.
• Assistant Examiner(s): Williamson, Michael A.
• Application Number:
  US08/224,002
• Time in Patent Office: 755 Days
• Field of Search: 428/34.2, 428/34.3, 264/173, 264/512, 264/524, 206/233, 206/494, 206/812, 206/209, 206/524.2, 427/536, 427/539, 427/316, 427/326, 427/223, 241/DIG. 38
• US Class Current: 427/536
• CPC Class Codes: D21H 19/00 Coated paper coated fibreboard D21J1/08; Coating material recording sheets characterised by the coating used to improve ink, dye or pigment receptivity B41M5/50
• CPC Class Codes: D21H 19/20 comprising macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
• CPC Class Codes: Y10S 241/38 Solid waste disposal

Abstract

A method of making and using a compostable paperboard container and package for liquids which is coated with a polymeric material capable of degrading under composting conditions and subsequently in the presence of light to form carbon dioxide, water, and biomass.

Claims

1. A method of making a compostable package for containing a liquid or a liquid containing material comprising,

providing a base of paperboard having an external surface and an internal surface;

treating at least one of said internal and external surfaces with corona discharge or a flame;

coating the internal surface of said paperboard with a biodegradable polymer capable of preventing leaks and coating the external surface with a biodegradable polymer wherein at least one of said internal and external polymer coatings contains a photodegradable polyolefin, wherein said base of paperboard and said coatings compost at substantially the same rate to carbon dioxide, water, and biomass and wherein at least said treated internal or external surface and said coating define a water insensitive inter-facial bond free of adhesive; and

forming said paperboard into a container wherein said internal surface forms the interior of the container and said external surface forms the exterior of the container.

2. The method according to claim 1, wherein said biodegradable polymer is an aliphatic polyester.

3. The method according to claim 2, wherein said biodegradable polymer is heat sealable, flexible, adhesive, resistant to stress cracks, and abrasion resistant.

4. The method according to claim 1, wherein said biodegradable polymer is selected from the group consisting of polycaprolactone, poly-3-hydroxybutyric acid, poly-3-hydroxyvaleric acid, polyglycolic acid, copolymers of glycolic acid and lactic acid, and polylactide.

5. The method according to claim 4, wherein said biodegradable polymer is polycaprolactone.

6. The method according to claim 2, wherein one or both of said biodegradable polymer has been added polyolefin further contains a blend of a second polymer, said second polymer selected from the group consisting of PVS, SAN, ABS, phenoxy, polycarbonate, nitrocellulose, polyvinylidene chloride, a styrene/allyl alcohol copolymer, polyethylene, polypropylene, natural rubber, a sytrene/butadiene elastomer and block copolymer, polyvinylacetaqte, polybutadiene, ethylene/propylene rubber, starch, and thermoplastic segmented polyurethane.

7. The method according to claim 6, wherein the second polymer is polyethylene.

8. The method according to claim 1, wherein the liquid or liquid containing material is selected from the group consisting of milk, juice, fruit punch, soda, frozen juice, iced tea, fabric softener, butter, margarine, a cosmetic, shampoo, conditioner, suntan lotion, body lotion, pancake syrup, cooking oil, a processed grain, fruit, vegetable, applesauce, a pasta sauce, a frozen vegetable, a frozen fruit, bread, a bread product, and a single-use wet wipe.

9. The method according to claim 8, wherein the liquid or liquid containing material is a single-use wet wipe.

10. A method of using a compostable package for containing a liquid or a liquid containing material comprising,

providing a base of paperboard having an external surface and an internal surface;

coating the internal surface of said paperboard with a biodegradable polymer capable of preventing leaks and coating the external surface with a biodegradable polymer wherein at least one of said internal and externals polymer coatings contains a photodegradable polyolefin, wherein said base of paperboard and said coatings compost at substantially the same rate to carbon dioxide, water, and biomass;

forming said paperboard into a container wherein said internal surface having said biodegradable polymer thereon forms the interior or the container and said external surface forms the exterior of the container;

sealing the edges and bottom of said container; and

placing into said container a liquid or a material containing a liquid.

11. The method according to claim 10, wherein the biodegradable film is a polyhydroxyaliphatic acid.

12. The method according to claim 10, wherein said biodegradable film is sealable, flexible, adhesive, resistant to stress cracks, and abrasion resistant.

13. The method according to claim 10, wherein said biodegradable film is selected from the group consisting of polycaprolactone, poly-3-hydroxybutyric acid, poly-3-hydroxyvaleric acid, polyglycolic acid and copolymers of glycolic acid and lactic acid, and polylactide.

14. The method according to claim 13, wherein said biodegradable film is polycaprolactone.

15. The method according to claim 10, wherein one or both of said biodegradable polymer and said photodegradable polyolefin further contain a blend of a second polymer, said second polymer selected from the group consisting of PVS, SAN, ABS, phenoxy, polycarbonate, nitrocellulose, polyvinylidene chloride, a styrene/allyl alcohol copolymer, polyethylene, polypropylene, natural rubber, a sytrene/butadiene elastomer and block copolymer, polyvinylacetaqte, polybutadiene, ethylene/propylene rubber, starch, and thermoplastic segmented polyurethane.

16. The method according to claim 15, wherein said second polymer is polyethylene.

17. The method according to claim 10, wherein the liquid or liquid containing material is selected from the group consisting of milk, juice, fruit punch, soda, frozen juice, iced tea, fabric softener, butter margarine, a cosmetic, shampoo, conditioner, suntan lotion, body lotion, pancake syrup, cooking oil, a processed grain, fruit, vegetable, applesauce, a pasta sauce, a frozen vegetable, a frozen fruit, bread, a bread product, and a single-use wet wipe.

18. The method according to claim 17, wherein the liquid or liquid containing material is a single-use wet wipe.

19. A method of composting a coated paperboard comprising:

providing a coated paperboard substrate having two sides and having a biodegradable linear aliphatic polyester on at least one side thereof and a photodegradable polyolefin on at least the other side thereof;

subjecting said coated paperboard to composting conditions to compost at substantially the same rate as said biodegradable polyester and said paperboard substrate to carbon dioxide, water and biomass; and

subjecting the remaining photodegradable polyolefin to light to cause substantially complete degradation thereof.