US5254607A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Biodegradable, liquid impervious films
Assignee: Tredegar Film Products LLC
•
Filing: 1991-06-26
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Granted: 1993-10-19
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Expires: 2011-06-26
Abstract
Abstract Liquid impervious, biodegradable films are disclosed. In particular, the films comprise a blend of an interpenetrated network of destructurized starch with ethylene/acrylic acid copolymers or ethylene/vinyl alcohol copolymers, and an aliphatic polyester such as polycaprolactone. Diapers, sanitary napkins, pantiliners, and the like, containing backsheets prepared from the foregoing materials are also disclosed.
Inventors
- 👤 Robert K. McBride
- 👤 James M. Adams
- 👤 Peter I. Chang
- 👤 Carl D. Ray
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 11:38
CPC Classifications
C; C08; C08J; C08J5/00; C08J5/18; A; A61; A61L; A61L15/00; A61L15/16; A61L15/22; A61L15/225; C08L; C08L23/00; C08L23/02; C08L23/04; C08L23/08; C08L3/00; C08L3/02; C08J2303/00; C08J2303/02; C08J2367/00; C08J2367/04; C08L2205/00; C08L2205/03; C08L23/0846; C08L23/0869; C08L67/00; C08L67/04
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
61 words
A biodegradable liquid impervious film comprising a blend of: (a) a biodegradable interpenetrated network of destructurized starch and a copolymer selected from the group consisting of ethylene acrylic acid copolymer and ethylene vinyl alcohol copolymer; and (b) a biodegradable aliphatic polyester, the weight ratio of said interpenetrated network of destructurized starch and copolymer to said aliphatic polyester being greater than 1:1.
Claim 2
Dependent Claim
61 words
A biodegradable liquid impervious film comprising a blend of: (a) a biodegradable interpenetrated network of destructurized starch and a copolymer selected from the group consisting of ethylene acrylic acid copolymer and ethylene vinyl alcohol copolymer; and (b) a biodegradable aliphatic polyester, the weight ratio of said interpenetrated network of destructurized starch and copolymer to said aliphatic polyester being greater than 1:1.
Claim 3
Dependent Claim
40 words
The biodegradable film of claim 1 wherein the film comprises from about 55% to about 95% by weight of said interpenetrated network of destructurized starch and copolymer, and from about 5% to about 45% by weight of the aliphatic polyester.
Claim 4
Dependent Claim
32 words
The biodegradable film of claim 2 wherein less than 40% of the starch in the film is free and in the form of particles having an average number diameter below 1 micrometer.
Claim 5
Dependent Claim
14 words
The biodegradable film of claim 1 wherein the copolymer is an ethylene/acrylic acid copolymer.
Claim 6
Dependent Claim
23 words
The biodegradable film of claim 4 wherein the copolymer has an acrylic acid content of from about 3% to about 30% by weight.
Claim 7
Dependent Claim
14 words
The biodegradable film of claim 1 wherein the copolymer is an ethylene/vinyl alcohol copolymer.
Claim 8
Dependent Claim
23 words
The biodegradable film of claim 6 wherein the copolymer has a vinyl alcohol content of from about 50% to about 80 mole %.
Claim 9
Dependent Claim
40 words
The biodegradable film of claim 2 wherein the film comprises from about 60% to about 85% by weight of the interpenetrated network of destructurized starch and copolymer, and from about 15% to about 40% by weight of the aliphatic polyester.
Claim 10
Dependent Claim
32 words
The biodegradable film of claim 8 wherein less than 20% of the starch in the film is free and in the form of particles having an average number diameter below 1 micrometer.
Claim 11
Dependent Claim
12 words
The biodegradable film of claim 1 wherein the aliphatic polyester is polycaprolactone.
Claim 12
Dependent Claim
24 words
The biodegradable film of claim 1 wherein the aliphatic polyester is the oxidation product of an ethylene-carbon monoxide copolymer and a peroxyacid oxidizing agent.
Claim 13
Dependent Claim
25 words
The biodegradable film of claim 1 wherein the aliphatic polyester is a polyhydroxybutyrate-valerate copolymer having a valerate content-from about 10 to about 24 mole %.
Claim 14
Dependent Claim
17 words
The biodegradable liquid impervious film of claim 1, wherein the aliphatic polyester is an aliphatic polyester-based polyurethane.
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1996-10-18 | 1997-04-19 | 1997-10-19 | $2000.00 | Window Closed / Lapsed |
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