Biodegradable prod. simple mfr. useful for a blown foamy structure - by passing a natural polymer at below gelatinisation temp. into or through a heated mould, for packaging for high dimensional stability

摘要

Biodegradable foam product (35) is formed by: (a) passing a pressurised natural polymer(s) at below gelatinisation temperature, into or through a mould (23); (b) heating to cause crosslinking of the polymer and a rise to baking temperature. Also claimed are: (i) apparatus including a closed mould (23); and (ii) an appts. for mfg. biodegradable prods. comprising an extrusion die.