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US4136072A Expired / Lapsed US ⏱️ 0.0 years remaining

Thermoplastic polyolefin film compositions

Assignee: Millennium Petrochemicals Inc
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Filing: 1977-05-24
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Granted: 1979-01-23
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Expires: 1997-05-24
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Abstract

Abstract Improved thermoplastic polyolefin films are provided with the desired improvements in certain properties to make them especially suitable for packaging fresh meat and other foods, as well as for packaging other products, by the use of selected additives to improve or maintain certain desired properties, such as, gloss, anti-fogging, tensile strength, tear resistance, cling and tack, low blocking (that is low, film to metal coefficient of friction), low water transmission, desired levels of permeability to oxygen and carbon dioxide, heat sealability at lower temperatures but with an adequate range (without burn through), and the like. A preferred composition, comprises a transparent thin polyethylene film with at least one additive and a shellac compound. A particularly preferred composition comprises a copolymer of low density polyethylene and vinyl acetate plus one or more additives, and a shellac material.

Inventors

  • 👤 Charles E. Ladish
  • 👤 Earl S. Hill, Jr.

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-02 18:01
CPC Classifications
C; C08; C08L; C08L23/00; C08L23/02; C08L23/04; C08L23/08; C08L23/0846; C08L23/0853; C08L23/06; C08L23/16; C08L91/00

Claims Analysis

Total Claims: 13
Claim 1
Independent Claim 30 words
A thermoplastic polyolefin film composition suitable for packaging use comprising a polyolefin containing one or more additives having a plasticizing effect and about 0.05% to about 1.0% of a shellac.
Claim 2
Dependent Claim 30 words
A thermoplastic polyolefin film composition suitable for packaging use comprising a polyolefin containing one or more additives having a plasticizing effect and about 0.05% to about 1.0% of a shellac.
Claim 3
Dependent Claim 25 words
A film composition in accordance with claim 1 in which the additives are intimately mixed together with the polyolefin prior to formation of said film.
Claim 4
Dependent Claim 32 words
A film composition as claimed in claim 2 in which the polyolefin is a low density polyethylene and which contains from about 0.2% up to about 5% of a high density polyethylene.
Claim 5
Dependent Claim 71 words
A transparent thermoplastic polyolefin wrapping film comprising: a. a predominant amount of an ethylene copolymer, b. one or more plasticizer additives in sufficient quantity to provide the predetermined requisite properties of gloss, anti-fog, contact clarity, tackifier, cling, low resistance to blocking and adequately low film to metal coefficient of friction, and c. a shellac in sufficient quantity to impart desired prerequisite properties of tack, gloss, strength, cohesiveness, and improved heat sealability.
Claim 6
Dependent Claim 71 words
A transparent thermoplastic polyolefin wrapping film comprising: a. a predominant amount of an ethylene copolymer, b. one or more plasticizer additives in sufficient quantity to provide the predetermined requisite properties of gloss, anti-fog, contact clarity, tackifier, cling, low resistance to blocking and adequately low film to metal coefficient of friction, and c. a shellac in sufficient quantity to impart desired prerequisite properties of tack, gloss, strength, cohesiveness, and improved heat sealability.
Claim 7
Dependent Claim 104 words
A film composition suitable for making film for use in wrapping fresh meat and other food products comprising: a. a copolymer of ethylene and vinyl acetate, b. at least one plasticizer additive in an amount of about 0.2 to 12% by weight intimately associated with and dispersed throughout said film to enhance properties of flexibility, anti-fog, contact clarity, tack, and c. a shellac in an amount of about 0.05 to about 1.0% intimately associated with and dispersed throughout said film to lower and broaden the heat sealing temperature range, to enhance the properties of gloss and to increase tack and cling of said film.
Claim 8
Dependent Claim 104 words
A film composition suitable for making film for use in wrapping fresh meat and other food products comprising: a. a copolymer of ethylene and vinyl acetate, b. at least one plasticizer additive in an amount of about 0.2 to 12% by weight intimately associated with and dispersed throughout said film to enhance properties of flexibility, anti-fog, contact clarity, tack, and c. a shellac in an amount of about 0.05 to about 1.0% intimately associated with and dispersed throughout said film to lower and broaden the heat sealing temperature range, to enhance the properties of gloss and to increase tack and cling of said film.
Claim 9
Dependent Claim 67 words
A film composition suitable for use in making thin films of less than 1 mil comprising: a. a transparent thermoplastic ethylene copolymer, b. from about 0.2 to about 12% of one or more plasticizing additives, c. from about 0.05 to about 1% of a shellac d. from about 0.1 to about 5% of an elastomer, said components being intimately mixed and fabricated into a thin film form.
Claim 10
Dependent Claim 67 words
A film composition suitable for use in making thin films of less than 1 mil comprising: a. a transparent thermoplastic ethylene copolymer, b. from about 0.2 to about 12% of one or more plasticizing additives, c. from about 0.05 to about 1% of a shellac d. from about 0.1 to about 5% of an elastomer, said components being intimately mixed and fabricated into a thin film form.
Claim 11
Dependent Claim 20 words
A composition as claimed in claim 6 which contains from about 0.2% up to about 5% of high density polyethylene.
Claim 12
Dependent Claim 96 words
A thin film composition suitable for wrapping meat and other fresh food products comprising: a. a copolymer of low density polyethylene and vinyl acetate in an amount equal to about 92.75% by weight, b. one or more plasticizers in an amount of about 2.75% by weight, c. a shellac in an amount of about 0.5% by weight, d. a high density polyethylene in an amount of about 2.75% by weight, and e. an elastomer in an amount of about 1.25% by weight, all of said ingredients being intimately mixed together and fabricated into a thin film.
Claim 13
Dependent Claim 96 words
A thin film composition suitable for wrapping meat and other fresh food products comprising: a. a copolymer of low density polyethylene and vinyl acetate in an amount equal to about 92.75% by weight, b. one or more plasticizers in an amount of about 2.75% by weight, c. a shellac in an amount of about 0.5% by weight, d. a high density polyethylene in an amount of about 2.75% by weight, and e. an elastomer in an amount of about 1.25% by weight, all of said ingredients being intimately mixed together and fabricated into a thin film.

References Cited (Backward Citations)

GB645914A Cited
GB781467A Cited
US2928797A Cited
US3232895A Cited
US3313754A Cited
US3615106A Cited
US3853606A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1982-01-22 1982-07-24 1983-01-23 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1986-01-22 1986-07-24 1987-01-23 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1990-01-22 1990-07-24 1991-01-23 $7700.00 Window Closed / Lapsed

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