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Stretched film of lactic acid-based polymer

Assignee: Mitsui Chemicals Inc
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Filing: 1996-11-20
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Granted: 1998-06-16
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Expires: 2016-11-20
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Abstract

Abstract The stretched film of the lactic acid-based polymer of the invention can degrade under natural environment, and additionally has an excellent mechanical strength and durability. By use of a lubricant in combination with an inorganic filler, these properties are further improved and thickness accuracy is enhanced. Consequently, the stretched film of the lactic acid-based polymer of the invention can be widely applied to a prepaid card and other various film materials, lamination materials and packaging materials. Even though abandoned after use in the natural environment, the stretched film relatively quickly decomposes into carbon dioxide and water and does not accumulate as waste.

Inventors

  • 👤 Shuhei Ikado
  • 👤 Takayuki Kuroki
  • 👤 Masumi Saruwatari
  • 👤 Naoki Kobayashi
  • 👤 Kazuhiko Suzuki
  • 👤 Hirotaka Wanibe

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-27 13:13
CPC Classifications
C; C08; C08J; C08J5/00; C08J5/18; B; B29; B29C; B29C55/00; C08K; C08K3/00; C08K3/01; C08J2367/00; C08J2367/04; Y; Y10; Y10S; Y10S428/00; Y10S428/91; Y10T; Y10T428/00; Y10T428/25; Y10T428/256; Y10T428/258; Y10T428/259; Y10T428/31504; Y10T428/31786

Claims Analysis

Total Claims: 14
Claim 1
Independent Claim 149 words
A stretched film of a polylactic acid or a copolymer of lactic acid and other aliphatic hydroxycarboxylic acid comprising 3 to 25 parts by weight of one or more inorganic fillers selected from the group consisting of titanium oxide having an average particle size of 0.1 to 0.5 μm, calcium carbonate having an average particle size of 0.3 to 6 μm, barium sulfate having an average particle size of 0.1 to 2 μm, silica having an average particle size of 1 to 12 μm, kaolin having an average particle size of 0.5 to 10 μm, and talc having an average particle size of 0.1 to 10 μm, and 0.1 to 2 parts by weight of a lubricant for 100 parts by weight of polylactic acid or a copolymer of lactic acid and other aliphatic hydroxycarboxylic acid, and being stretched 1.3 to 5 times to one or more axial directions.
Claim 2
Dependent Claim 149 words
A stretched film of a polylactic acid or a copolymer of lactic acid and other aliphatic hydroxycarboxylic acid comprising 3 to 25 parts by weight of one or more inorganic fillers selected from the group consisting of titanium oxide having an average particle size of 0.1 to 0.5 μm, calcium carbonate having an average particle size of 0.3 to 6 μm, barium sulfate having an average particle size of 0.1 to 2 μm, silica having an average particle size of 1 to 12 μm, kaolin having an average particle size of 0.5 to 10 μm, and talc having an average particle size of 0.1 to 10 μm, and 0.1 to 2 parts by weight of a lubricant for 100 parts by weight of polylactic acid or a copolymer of lactic acid and other aliphatic hydroxycarboxylic acid, and being stretched 1.3 to 5 times to one or more axial directions.
Claim 3
Dependent Claim 32 words
The stretched film of a polylactic acid or a copolymer of lactic acid and other aliphatic hydroxycarboxylic acid according to claim 1 wherein the film thickness is from 0.01 to 2 mm.
Claim 4
Dependent Claim 40 words
The stretched film of a polylactic acid or a copolymer of lactic acid and other aliphatic hydroxycarboxylic acid according to claim 1 wherein the inorganic filler is titanium oxide having an average particle size of from 0.1 to 0.5 μm.
Claim 5
Dependent Claim 40 words
A material for prepaid card, said material comprising the stretched film of a polylactic acid or a copolymer of lactic acid and other aliphatic hydroxycarboxylic acid having a film thickness of from 0.1 to 0.5 mm according to claim 3.
Claim 6
Dependent Claim 30 words
The stretched film of a polylactic acid or a copolymer of lactic acid and other aliphatic hydroxycarboxylic acid according to claim 1 wherein folding endurance is at least 900 times.
Claim 7
Dependent Claim 40 words
A material for prepaid card, said material comprising the stretched film of a polylactic acid or a copolymer of lactic acid and other aliphatic hydroxycarboxylic acid having a film thickness of from 0.1 to 0.5 mm according to claim 5.
Claim 8
Dependent Claim 43 words
The stretched film of a polylactic acid or a copolymer of lactic acid and other aliphatic hydroxycarboxylic acid according to claim 1 wherein the lubricant is one or more compounds selected from the group consisting of aliphatic amides, aliphiatic esters and metallic soaps.
Claim 9
Dependent Claim 40 words
A material for prepaid card, said material comprising the stretched film of a polylactic acid or a copolymer of lactic acid and other aliphatic hydroxycarboxylic acid having a film thickness of from 0.1 to 0.5 mm according to claim 7.
Claim 10
Dependent Claim 51 words
The stretched film of a polylactic acid or a copolymer of lactic acid and other aliphatic hydroxycarboxylic acid according to claim 1 wherein the film has a thickness of from 0.01 to 2 mm, variation coefficient of thickness of not more than 1.3%, and folding endurance of at least 900 times.
Claim 11
Dependent Claim 40 words
The stretched film of a polylactic acid or a copolymer of lactic acid and other aliphatic hydroxycarboxylic acid according to claim 9 wherein the inorganic filler is titanium oxide having an average particle size of from 0.1 to 0.5 μm.
Claim 12
Dependent Claim 40 words
A material for prepaid card, said material comprising the stretched film of a polylactic acid or a copolymer of lactic acid and other aliphatic hydroxycarboxylic acid having a film thickness of from 0.1 to 0.5 mm according to claim 10.
Claim 13
Dependent Claim 40 words
A material for prepaid card, said material comprising the stretched film of a polylactic acid or a copolymer of lactic acid and other aliphatic hydroxycarboxylic acid having a film thickness of from 0.1 to 0.5 mm according to claim 9.
Claim 14
Dependent Claim 40 words
A material for prepaid card, said material comprising the stretched film of a polylactic acid or a copolymer of lactic acid and other aliphatic hydroxycarboxylic acid having a film thickness of from 0.1 to 0.5 mm according to claim 1.

References Cited (Backward Citations)

WO1990001521A1 Cited
WO1992001548A1 Cited
EP0510998A2 Cited
JPH0542786A Cited
JPH0570696A Cited
JPH06340753A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2001-06-15 2001-12-15 2002-06-16 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2005-06-15 2005-12-15 2006-06-16 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2009-06-15 2009-12-15 2010-06-16 $7700.00 Window Closed / Lapsed

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