| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a multilayer film having biodegradability which, in particular, has improved transparency and water vapor permeability of the film, further has high tear strength, and has high stability in the natural environment and also is excellent in economical efficiency although a component originated from a natural substance is introduced and is biodegradable. <P>SOLUTION: The multilayer film includes: an middle layer which contains gelatinized material of an oxidized starch having such a structure that a part of glucose unit is cut between C-2 and C-3 and carboxyl groups are formed at the C-2 and C-3 and a biodegradable resin; and an outer layer and an inner layer each of which is made from a biodegradable resin. Here, an composition (A) including the oxidized starch and biodegradable resin in the middle layer has a moisture content fraction of 5,000 mass ppm or less, and contains the gelatinized material of the oxidized starch of 25 to 60 mass% and the biodegradable resin of 75 to 40 mass% based on the total amount of the gelatinized material of the oxidized starch and biodegradable resin, and each of the inner layer and outer layer contains polylactic acid-based resin (B) of 5 to 50 mass% and a biodegradable resin (C) except the polylactic acid-based resin, of 50 to 95 wt.% based on the total amount of the biodegradable resin. <P>COPYRIGHT: (C)2012,JPO&INPIT</p> |
