Compostable multilayer structures, methods for manufacture, and articles prepared therefrom

US5849374A · kind A · utility

Assignee

• CARGILL, INCORPORATED · US

Inventors

• Patrick R. Gruber · Blaine, US
• Jeffrey John Kolstad · Wayzata, US
• James Lunt · Sarnia, CA
• Christopher M. Ryan · Dayton, US
• Ali El-Afandi · Maplewood, US
• James Nangeroni · Doylestown, US
• Nancy Uzelac Buehler · Minneapolis, US
• Mark Hartmann · Minnetonka, US
• Jed Richard Randall · Minneapolis, US
• Andrea L. Brosch · Eden Prairie, US

Key dates

• Filing date: Sep 28, 1995
• Grant date: Dec 15, 1998
• Expiry date: Sep 28, 2015

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T428/3179
• WIPO field: Surface technology, coating
• WIPO sector: Chemistry

Abstract

A compostable multilayer structure in the form of a film, sheet, laminate, and the like, which comprises a core layer having a first surface and a second surface, a first blocking reducing layer covering the first surface of the core layer, and a second blocking reducing layer covering the second surface of the core layer. The core layer contains a lactic acid residue-containing polymer and has a glass transition temperature (T.sub.g) below about 20.degree. C. The first and second blocking reducing layers include a polymer composition of a hydrolyzable polymer and have a T.sub.g above about 50.degree. C. The multilayer structure can be used for preparing bags and wrappers.