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US4134875A Expired / Lapsed US ⏱️ 0.0 years remaining

Polyolefin film for agricultural use

Assignee: Repsol Quimica SA
•
Filing: 1978-03-17
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Granted: 1979-01-16
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Expires: 1998-03-17
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Abstract

Abstract Polyethylene or EVA copolymer film which includes up to about 15% by weight of an additive preferably a mixture of alunite - aluminum hydroxide is disclosed for particular use as a cover for agricultural purposes. The disclosed film has improved properties which provide growth of plants and/or crops by reducing thermal losses to the atmosphere and by minimizing shadow formation. The physical characteristics of the film are equal to or better than conventional films.

Inventors

  • 👤 Graciano J. Tapia

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 06:11
CPC Classifications
A; A01; A01G; A01G9/00; A01G9/14; A01G9/1438; C; C08; C08K; C08K3/00; C08K3/18; C08K3/20; C08K3/22; C08K3/30; Y; Y02; Y02A; Y02A40/00; Y02A40/10; Y02A40/25

Claims Analysis

Total Claims: 16
Claim 1
Independent Claim 74 words
Polymeric composition especially well suited for agricultural use comprising from about 80% or more polyolefin and from about 1% to about 15% by weight of an additive referred to as a basic metallic sulfate and having the formula (SO.sub.4).sub.4 M.sub.6.sup.111 . M.sub.2.sup.1 12(OH) wherein M 1 is a monovalent metal, M 111 is a trivalent metal, said film having low thermal transmittance properties between 7 and 14 micron wavelengths and excellent light diffusion properties.
Claim 2
Dependent Claim 74 words
Polymeric composition especially well suited for agricultural use comprising from about 80% or more polyolefin and from about 1% to about 15% by weight of an additive referred to as a basic metallic sulfate and having the formula (SO.sub.4).sub.4 M.sub.6.sup.111 . M.sub.2.sup.1 12(OH) wherein M 1 is a monovalent metal, M 111 is a trivalent metal, said film having low thermal transmittance properties between 7 and 14 micron wavelengths and excellent light diffusion properties.
Claim 3
Dependent Claim 17 words
The polymeric composition as defined in claim 1 wherein said polyolefin is polyethylene or copolymers of ethylene.
Claim 4
Dependent Claim 15 words
The polymeric composition as defined in claim 1 wherein said additive also includes aluminum hydroxide.
Claim 5
Dependent Claim 15 words
The polymeric composition as defined in claim 1 wherein said basic metallic sulfate is alunite.
Claim 6
Dependent Claim 36 words
The polymeric composition as defined in claim 1 wherein said additive comprises a mixture of alunite and aluminum hydroxide (or hydrated alumina) which together is present in an amount ranging from 3% to 10% by weight.
Claim 7
Dependent Claim 26 words
The polymeric composition as defined in claim 5 wherein said polyolefin is polyethylene which is present in an amount ranging from 90% to 97% by weight.
Claim 8
Dependent Claim 29 words
The polymeric composition as defined in claim 5 wherein said polyolefin is an ethylene-vinyl acetate copolymer which is present in an amount ranging from 90% to 97% by weight.
Claim 9
Dependent Claim 25 words
The polymeric composition as defined in claim 3 wherein the ratio of basic metallic sulfate and aluminum hydroxide ranges from about 4:1 to about 1:4.
Claim 10
Dependent Claim 14 words
The polymeric composition as defined in claim 1 formed as film or sheet material.
Claim 11
Dependent Claim 15 words
The polymeric composition as defined in claim 3 formed as a film or sheet material.
Claim 12
Dependent Claim 59 words
Polymeric film for covering plants or crops comprising polyethylene or copolymers thereof with an effective amount of basic metallic sulfate having the formula: (SO.sub.4).sub.4 M.sub.6.sup.111 M.sub.2.sup.1 12(OH) wherein M 1 is a monovalent metal, M 111 is a trivalent metal, for imparting to said film low thermal transmittance properties between 7 and 14 microns and excellent light diffusion properties.
Claim 13
Dependent Claim 59 words
Polymeric film for covering plants or crops comprising polyethylene or copolymers thereof with an effective amount of basic metallic sulfate having the formula: (SO.sub.4).sub.4 M.sub.6.sup.111 M.sub.2.sup.1 12(OH) wherein M 1 is a monovalent metal, M 111 is a trivalent metal, for imparting to said film low thermal transmittance properties between 7 and 14 microns and excellent light diffusion properties.
Claim 14
Dependent Claim 32 words
The polymeric film of claim 11 further including aluminum hydroxide admixed with said basic metallic sulfate, said combined additive being present in an amount up to 20% by weight of said film.
Claim 15
Dependent Claim 25 words
A composition according to claim 3 further including from about 0.05 to about 2% by weight of an ultra-violet absorber such as benzophenone or benzotriazole.
Claim 16
Dependent Claim 26 words
A polymeric film according to claim 12 further including from about 0.05 to about 2% by weight of an ultra-violet absorber such as benzophenone or benzotriazole.

References Cited (Backward Citations)

US3252250A Cited
US3592792A Cited
US3953565A Cited
US4024087A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1982-01-15 1982-07-17 1983-01-16 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1986-01-15 1986-07-17 1987-01-16 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1990-01-15 1990-07-17 1991-01-16 $7700.00 Window Closed / Lapsed

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