Biodegradable bags and processes for making such biodegradable bags

• US 5,679,421 A
• Filed: 10/30/1995
• Issued: 10/21/1997
• Est. Priority Date: 10/30/1995
• Status: Expired due to Term

• Current Assignee: William F. Brinton Jr
• Original Assignee: William F. Brinton Jr
• Inventors: Brinton, William F. Jr.
• Primary Examiner(s): Dye, Rena
• Application Number:
  US08/549,933
• Time in Patent Office: 722 Days
• Field of Search: 383/1, 428/35.2, 428/35.4, 428/35.7, 428/36.6, 428/36.7, 428/532, 428/533, 428/537.5, 428/511, 428/518, 428/34.2, 428/34.3, 428/481, 428/913, 428/480, 428/483, 428/514
• US Class Current: 428/34.3
• CPC Class Codes: B32B 2307/7163 Biodegradable
• CPC Class Codes: B32B 2317/122 Kraft paper
• CPC Class Codes: B32B 2439/00 Containers; Receptacles
• CPC Class Codes: B32B 27/10 of paper or cardboard
• CPC Class Codes: B32B 27/28 comprising synthetic resins not wholly covered by any one of the sub-groups B32B27/30 - B32B27/42
• CPC Class Codes: B32B 29/00 Layered products comprising a layer of paper or cardboard
• CPC Class Codes: B32B 7/12 using interposed adhesives or interposed materials with bonding properties
• CPC Class Codes: B65D 65/466 Bio- or photodegradable packaging materials
• CPC Class Codes: Y02W 90/10 Bio-packaging, e.g. packing containers made from renewable resources or bio-plastics
• CPC Class Codes: Y10S 428/913 Material designed to be responsive to temperature, light, moisture
• CPC Class Codes: Y10T 428/1307 Bag or tubular film [e.g., pouch, flexible food casing, envelope, etc.]
• CPC Class Codes: Y10T 428/1334 Nonself-supporting tubular film or bag [e.g., pouch, envelope, packet, etc.]
• CPC Class Codes: Y10T 428/3179 Next to cellulosic
• CPC Class Codes: Y10T 428/31971 Of carbohydrate

Abstract

Biodegradable bags can be formed out of two-ply sheet materials that include an outer ply of kraft paper and an inner ply of biodegradable thermoplastic material. The two-ply sheets are formed and connected together with the use of biodegradable adhesives that do not constitute barriers to biodegradation of the bag material in a composting environment. The sheets are preferably laminated and joined together, using heat-sealing procedures. Preferred biodegradable materials are polyvinyl alcohol, hydroxyethylcellulose polymer, polyethylene glycol polymer, polycaprolactone, polylactic acid, hydroxybutyrate polymer, hydroxyvalerate polymer, and a copolymer of hydroxybutyrate and hydroxyvalerate.

Claims

1. A multi-ply laminate bag material consisting of a paper layer, a biodegradable polymer resin layer, and an intervening biodegradable adhesive layer between the paper layer and polymer resin layer;

said biodegradable adhesive layer being formed of starch; and

said polymer resin layer being formed of a material selected from the group consisting of hydroxybutyrate polymer, hydroxyvalerate polymer, and a copolymer of hydroxybutyrate and hydroxyvalerate.

2. The bag material, as described in claim 1, wherein said resin layer is hydroxybutyrate polymer.

3. The bag material, as described in claim 1, wherein said resin layer is hydroxyvalerate polymer.

4. The bag material, as described in claim 1, wherein said resin layer is a copolymer of hydroxybutyrate and hydroxyvalerate.