US4275544A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Vacuum packaging method
Assignee: Kureha Corp
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Filing: 1979-09-12
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Granted: 1981-06-30
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Expires: 1999-09-12
Abstract
Abstract An improved method of vacuum packaging by using a specific laminated film as a package film, the laminated film being composed of a plastically deformable layer of a synthetic resin having a yield stress more than 50 kg/cm 2 at a temperature of 23° C. and an elongation of less than 30% at elastic limit at a shaping temperature of 50° to 180° C. and an elastic layer of a synthetic resin having an elongation of more than 40% at elastic limit at the shaping temperature.
Inventors
- 👤 Nobuyuki Hisazumi
- 👤 Masataka Yamamoto
- 👤 Tsutomu Uehara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 08:00
CPC Classifications
B; B65; B65B; B65B31/00; B65B11/00; B65B11/50; B65B11/52
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
238 words
A method of vacuum packaging comprising the steps of: (a) cup-shape-forming in a metal mold at a temperature of 50° to 180° C. under vacuum, a laminate film which is composed of (1) a plastically deformable layer of a synthetic resin having a yield stress larger than 50 kg/cm 2 at a temperature of 23° C. and an elongation of less than 30% at the elastic limit at the shaping temperature and (2) an elastic layer of a synthetic resin having an elongation of more than 40% at the elastic limit at said shaping temperature; (b) placing a base film provided with a plurality of small holes for passage of air adjacent to the metal mold; (c) placing articles or materials to be packed at positions on said base film corresponding to the cup-shaped hollows in said laminate film; (d) bringing the flat edge part of said cup-shape formed laminate film into contact with the edge part of said base film; (e) evacuating the interior of the spaces formed by the cup-shape hollows of said laminate film and said base film through said holes provided in said base film; and (f) releasing the vacuum which had been established in step (a) between said metal mold and said cup-shape formed laminate film thereby producing a tight package of said articles or materials having closely adhered laminate film, with tightly closed holes in said base film with said laminate film.
Claim 2
Independent Claim
238 words
A method of vacuum packaging comprising the steps of: (a) cup-shape-forming in a metal mold at a temperature of 50° to 180° C. under vacuum, a laminate film which is composed of (1) a plastically deformable layer of a synthetic resin having a yield stress larger than 50 kg/cm 2 at a temperature of 23° C. and an elongation of less than 30% at the elastic limit at the shaping temperature and (2) an elastic layer of a synthetic resin having an elongation of more than 40% at the elastic limit at said shaping temperature; (b) placing a base film provided with a plurality of small holes for passage of air adjacent to the metal mold; (c) placing articles or materials to be packed at positions on said base film corresponding to the cup-shaped hollows in said laminate film; (d) bringing the flat edge part of said cup-shape formed laminate film into contact with the edge part of said base film; (e) evacuating the interior of the spaces formed by the cup-shape hollows of said laminate film and said base film through said holes provided in said base film; and (f) releasing the vacuum which had been established in step (a) between said metal mold and said cup-shape formed laminate film thereby producing a tight package of said articles or materials having closely adhered laminate film, with tightly closed holes in said base film with said laminate film.
Claim 3
Dependent Claim
28 words
The method according to claim 1 in which the plastically deformable layer and/or the elastic layer of said laminated film are composed of a plurality of resinous layers.
Claim 4
Dependent Claim
28 words
The method according to claim 1, in which the total thickness of the plastically deformable layer of said laminate film is in the range of 3 to 100μ.
Claim 5
Dependent Claim
27 words
The method according to claim 1, in which the total thickness of the elastic layer of said laminated film is in the range of 10 to 100μ.
Claim 6
Dependent Claim
23 words
The method according to claim 1, in which the total thickness of the laminated film is in the range of 40 to 150μ.
Claim 7
Dependent Claim
46 words
The method according to claim 1, in which the plastically deformable layer of said laminated film comprises a first resinous layer highly impermeable to gases and a second resinous layer having a yield stress less than that of said first resinous layer at the shaping temperature.
Claim 8
Dependent Claim
35 words
The method according to claim 6, in which the second resinous layer serving as a plastically deformable layer of said laminated film has a yield stress less than 5 kg/cm 2 at said shaping temperature.
Claim 9
Dependent Claim
51 words
The method according to claim 1, in which the plastically deformable layer of said laminated film is formed of a resin which is readily plastically deformable at the shaping temperature by a stress which is less than 1/3 of the yield stress of the film at a temperature of 23° C.
Claim 10
Dependent Claim
38 words
The method according to claim 8, in which the plastically deformable layer of said laminated film is formed of a resinous material which is easily deformable plastically by a stress below 10 kg/cm 2 at said shaping temperature.
Claim 11
Dependent Claim
23 words
The method according to claim 1, in which the laminated film has an elastic recovery rate of above 80% at said shaping temperature.
Claim 12
Dependent Claim
40 words
The method according to claim 1, in which the plastically deformable layer of said laminated film is composed of at least one resinous material selected from the group consisting of vinylidene chloride copolymer saponified ethylenevinyl acetate copolymers, and acrylonitrile resins.
Claim 13
Dependent Claim
41 words
The method according to claim 1, in which the elastic layer of said laminated film is composed of at least one resinous material selected from the group consisting of plasticized polyvinyl chloride, 1,2-polybutadiene and stretched and oriented vinylidene chloride-vinyl chloride copolymers.
Claim 14
Dependent Claim
22 words
The method according to claim 1 or 2, in which said shaping temperature is in the range of 70° to 150° C.
Claim 15
Dependent Claim
31 words
The method according to claim 1 or 2, in which said laminated film is shape-formed under a stress between the elastic limits of the plastically deformable layer and the elastic layer.
References Cited (Backward Citations)
US3663240A
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FR2079331B1
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USRE30009E
Cited
FR2141043A5
Cited
FR2183932B1
Cited
FR2282371B1
Cited
FR2310935A1
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US4164109A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-06-29 | 1984-12-29 | 1985-06-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-06-29 | 1988-12-29 | 1989-06-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-06-29 | 1992-12-29 | 1993-06-30 | $7700.00 | Window Closed / Lapsed |