EP0507554B1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Degradable foam, process for its preparation and use of same
Assignee: Mitsui Chemicals Inc
•
Filing: 1992-03-31
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Granted: 1996-10-02
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Expires: 2012-03-31
Abstract
No abstract record available.
Inventors
- 👤 Masanobu Ajioka
- 👤 Katashi Enomoto
- 👤 Akihiro Yamaguchi
- 👤 Kazuhiko Suzuki
- 👤 Takayuki Watanabe
- 👤 Yasuhiro Kitahara
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-23 15:00
CPC Classifications
C; C08; C08J; C08J9/00; C08J9/04; C08J9/06; C08J9/12; C08J9/14; C08J2367/00; C08J2367/04; Y; Y10; Y10S; Y10S521/00; Y10S521/916
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
93 words
A method for the preparation of a degradable foam, the method comprising foaming a thermoplastic polymer composition comprising polylactic acid or a copolymer of lactic acid and hydroxycarboxylic acid with a foaming agent thereby to generate numerous cells dispersed through the polymer, said polylactic acid or copolymer having a degree of polymerisation in the range 150 to 20 000 the foaming agent being selected from (1) decomposition type foaming agents; and (2) evaporation type foaming agents selected from the group consisting of ethane, propane, butane, pentane, hexane, heptane, ethylene, propylene and petroleum ether.
Claim 2
Dependent Claim
26 words
A method according to claim 1 wherein the foaming agent is a decomposition type foaming agent generating carbon dioxide or nitrogen gas by decomposition on heating.
Claim 3
Dependent Claim
24 words
A method according to claim 2 wherein the foaming agent is selected from sodium hydrogen carbonate, azodicarbonamide, N,N'-dinitrosopentamethylene tetramine, p,p'-oxybis (benzenesulfonylcarbazide), azobisisobutyronitrile and benzenesulfonylhydrazide.
Claim 4
Dependent Claim
16 words
A method according to claim 1 wherein the foaming agent is an evaporation type foaming agent.
Claim 5
Dependent Claim
16 words
A degradable foam as obtainable by the method of any one of claims 2 to 4.
Claim 6
Dependent Claim
26 words
A degradable foam according to claim 5 wherein the polymer composition consists substantially of polylactic acid or a copolymer of lactic acid and hydroxy carboxylic acid.
Claim 7
Dependent Claim
26 words
The degradable foam of claim 5 or claim 6 wherein the lactic acid is L-lactic acid, D-lactic acid or a mixture of L- and D-lactic acids.
Claim 8
Dependent Claim
29 words
The degradable foam of any one of claims 5 to 7 wherein the hydroxycarboxylic acid is glycolic acid, 3-hydroxylactic acid, 4-hydroxylactic acid, 3-hydroxyvaleric acid, 6-hydroxycaproic acid or mixture thereof.
Claim 9
Dependent Claim
15 words
A container prepared from the degradable foam of any one of claims 5 to 8.
Claim 10
Dependent Claim
16 words
A cushioning material prepared from the degradable foam of any one of claims 5 to 8.
References Cited (Backward Citations)
No citation records indexed.
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