Biodegradable or compostable material made from pre-gelled starch suspension and wood fibers and process of forming it

摘要

A process and materials for forming biodegradable containers that can hold food products in dry, damp or wet conditions are disclosed. The containers are produced through the use of a pre-gelled starch suspension that is unique in its ability to form hydrated gels and to maintain this gel structure in the presence of many other types of materials and at low temperatures. The process disclosed herein for forming a biodegradable material comprises the steps of: (a) forming a pre-gelled starch suspension or paper starch suspension that is maintained between 0 and 60 degree C; (b) mixing together wood fibers or wood flour having an aspect ratio between approximately 1: 2 and 1: 8, water and additional materials selected from the group comprising: (i) dry or damp starch; (ii) pre-gelled starch; (iii) wax, fatty alcohol, phospholipid and/or glycerol; (v) baking powder; and/or (vi) homogenous moldable composition of natural earth fillers, clays, bentonite, amorphous raw products, gypsum or calcium sulfate, minerals such as limestone, and man made materials such as fly-ash to form a homogeneous mixture ; (c) adding to the pre-gelled starch suspension the dry or damp, homogeneous mixture to form a homogenous moldable composition ; and (d) molding the homogenous moldable composition with heat to form a biodegradable material.