US4905838A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Easily-openable packaging container having notched inner surface layer
Assignee: Idemitsu Kosan Co Ltd
•
Filing: 1988-12-02
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Granted: 1990-03-06
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Expires: 2008-12-02
Abstract
Abstract The present invention relates to the use of a multilayer sheet for producing a multilayer container suitable for heat sterilization packaging, which makes the setting of the heat sealing condition at heat sealing of a lid member easy, and is able to make a package which not only has an excellent sealing property, but also a good easy openability and which can be opened with a stable opening force, provides a peeled surface having a good appearance and has an excelent resistance to boiling and retort treatment.
Inventors
- 👤 Takanori Suzuki
- 👤 Yukio Takata
- 👤 Takeshi Shinohara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 13:05
CPC Classifications
B; B32; B32B; B32B7/00; B32B7/04; B32B7/06; B65; B65D; B65D5/00; B65D5/42; B65D5/54; B29; B29C; B29C65/00; B29C65/02; B29C65/18; B29C65/74; B29C65/745; B29C65/76; B29C66/00; B29C66/01; B29C66/05; B29C66/10; B29C66/11; B29C66/112; B29C66/13; B29C66/131; B29C66/20; B29C66/24; B29C66/242; B29C66/2422; B29C66/24221; B29C66/50; B29C66/51; B29C66/53; B29C66/534; B29C66/5346; B29C66/53461; B29C66/54; B29C66/542; B29C66/70; B29C66/71; B29C66/72; B29C66/723; B29C66/73; B29C66/739; B29C66/7392; B29C66/80; B29C66/81; B29C66/814; B29C66/8141; B29C66/81427; B29C66/81431; B29C66/816; B29C66/8161; B29C66/83; B29C66/832; B29C66/8322; B32B27/00; B32B27/06; B32B27/08; B32B27/32; B65D77/00; B65D77/10; B65D77/20; B65D77/2024; B65D77/2028; B65D77/2032; B65D77/2044; B65D77/2048; B65D77/2052; B29C2793/00; B29C2793/0054; B29C66/7232; B29C66/72321; B29C66/7234; B29C66/72341; B29C66/737; B29C66/7377; B29C66/73771; B29C66/73773; B29C66/73775; B29C66/73921; B29C66/818; B29C66/8181; B32B2439/00; B65D2577/00; B65D2577/10; B65D2577/20; B65D2577/2025; B65D2577/2033; B65D2577/2041; B65D2577/205; B65D2577/2066; B65D2577/2075; B65D2577/2083
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
187 words
A multilayer container comprising a multilayer structure shaped to define a container portion having an opening and a flange portion surrounding the opening, said flange portion including a planar portion arranged adjacent to said opening; said multilayered structure including a layer forming an inner surface layer of the container portion and another layer contacting the inner surface layer and being laminated thereto; a notch extending into said inner surface layer and being located at an inner peripheral portion of said flange portion, said notch being positioned inwardly of at least a part of the planar portion so that upward peeling of the inner surface layer away from said another layer allows at least a part of the inner surface layer in the planar portion of the flange portion of said multilayered structure to be separated from the another layer; at least a part of the planar portion being adapted to be heat sealed to a lid member for the container and to form a bond with said lid member exhibiting a peel strength greater than the interlaminar strength of the inner surface layer and the another layer.
Claim 2
Dependent Claim
187 words
A multilayer container comprising a multilayer structure shaped to define a container portion having an opening and a flange portion surrounding the opening, said flange portion including a planar portion arranged adjacent to said opening; said multilayered structure including a layer forming an inner surface layer of the container portion and another layer contacting the inner surface layer and being laminated thereto; a notch extending into said inner surface layer and being located at an inner peripheral portion of said flange portion, said notch being positioned inwardly of at least a part of the planar portion so that upward peeling of the inner surface layer away from said another layer allows at least a part of the inner surface layer in the planar portion of the flange portion of said multilayered structure to be separated from the another layer; at least a part of the planar portion being adapted to be heat sealed to a lid member for the container and to form a bond with said lid member exhibiting a peel strength greater than the interlaminar strength of the inner surface layer and the another layer.
Claim 3
Dependent Claim
45 words
A multilayer container according to claim 1, wherein the layer structure of said inner surface layer and said layer contacting thereto is a combination of (A) a resin mixture layer comprising a polypropylene base resin and a polyethylene base resin and (B) a polyethylene layer.
Claim 4
Dependent Claim
26 words
A multilayer container according to claim 2, wherein the weight ratio between said polypropylene base resin and said polyethylene base resin is from 50:50 to 97:3.
Claim 5
Dependent Claim
16 words
A multilayer container according to claim 2, wherein said polyethylene layer is a high density polyethylene.
Claim 6
Dependent Claim
34 words
A multilayer container according to claim 1, wherein said inner surface layer is a layer of a polyolefin resin, and said layer contacting to the inner surface layer is a layer of a metal.
Claim 7
Dependent Claim
26 words
A multilayer container according to claim 1, wherein said notch is provided at a non-heat seal surface of said inner peripheral portion of said flange portion.
Claim 8
Dependent Claim
26 words
A multilayer container according to claim 1, wherein another notch is further provided to an outer layer at the outer peripheral portion of said flange portion.
Claim 9
Dependent Claim
39 words
A multilayer container according to claim 1, wherein a rib or curl portion is provided at an outer end of the flange portion, and a cut-off portion is provided at the rib or curl portion near the flange level.
Claim 10
Dependent Claim
128 words
A multilayer container according to claim 1, further comprising a lid member covering the opening in the container portion and having a planar portion heat sealed to at least a part of the planar portion of the inner surface layer to provide a heat seal portion between the lid member and the inner surface layer; the notch extending into said inner surface layer being located inwardly of said heat seal portion and said multilayered structure possessing an interlaminar strength smaller than a peeling strength exhibited by the heat seal portion between the lid member and the inner surface layer so that during upward peeling of the lid member, a portion of the inner surface layer remains attached to said lid member and is separated from said another layer.
Claim 11
Dependent Claim
17 words
A multilayer container according to claim 9, wherein the notch is formed by pressing the lid member.
Claim 12
Dependent Claim
28 words
A multilayer container according to claim 10, wherein said notch and the heat seal portion are formed simultaneously by pressing the lid member with the application of heat.
Claim 13
Dependent Claim
33 words
A multilayer container according to claim 11, wherein pressing is effected by a heat seal ring comprising a sealing member for effecting heat sealing and a ring projection member for forming a notch.
Claim 14
Dependent Claim
21 words
A multilayer container according to claim 9, wherein said notch is located at an innermost portion of said heat seal portion.
Claim 15
Dependent Claim
267 words
A multilayer container comprising a multilayered structure shaped to define a container portion having an opening and a flange portion surrounding the opening, and a lid member covering the opening in the container portion; said flange portion including a planar portion arranged adjacent to said opening; said multilayered structure including a layer forming an inner surface layer of the container portion and another layer contacting the inner surface layer and being laminated thereto; a notch extending into said inner surface layer and being located at an inner peripheral portion of said flange portion, said notch being positioned inwardly of at least a part of the planar portion so that upward peeling of the inner surface layer away from said another layer allows at least a part of the inner surface layer in the planar portion of the flange portion of said multilayered structure to be separated from the another layer; said lid member having a planar portion heat-sealed to at least a part of the planar portion of the inner surface layer at a peripheral portion of the flange portion of the multilayered structure to provide a heat seal portion between the lid member and the inner surface layer, said notch being spaced from and located inwardly of said heat seal portion; said multilayered structure possessing an interlaminar strength smaller than a peeling strength exhibited by the heat seal portion between the lid member and the inner surface layer so that during upward peeling of the lid member, a portion of the inner surface layer remains attached to said lid member and separates from said another layer.
Claim 16
Dependent Claim
267 words
A multilayer container comprising a multilayered structure shaped to define a container portion having an opening and a flange portion surrounding the opening, and a lid member covering the opening in the container portion; said flange portion including a planar portion arranged adjacent to said opening; said multilayered structure including a layer forming an inner surface layer of the container portion and another layer contacting the inner surface layer and being laminated thereto; a notch extending into said inner surface layer and being located at an inner peripheral portion of said flange portion, said notch being positioned inwardly of at least a part of the planar portion so that upward peeling of the inner surface layer away from said another layer allows at least a part of the inner surface layer in the planar portion of the flange portion of said multilayered structure to be separated from the another layer; said lid member having a planar portion heat-sealed to at least a part of the planar portion of the inner surface layer at a peripheral portion of the flange portion of the multilayered structure to provide a heat seal portion between the lid member and the inner surface layer, said notch being spaced from and located inwardly of said heat seal portion; said multilayered structure possessing an interlaminar strength smaller than a peeling strength exhibited by the heat seal portion between the lid member and the inner surface layer so that during upward peeling of the lid member, a portion of the inner surface layer remains attached to said lid member and separates from said another layer.
Claim 17
Dependent Claim
66 words
A multilayer container according to claim 14, wherein a space of 0.5 to 10 mm is provided between said notch and an inner end of the heat seal portion provided between said lid member and said inner surface layer; a peeling strength from inside the covered container being substantially larger than a peeling strength from outside required to separate the lid member from the flange portion.
Claim 18
Dependent Claim
16 words
A multilayer container according to claim 15, wherein said space is from 1.5 to 5 mm.
Claim 19
Dependent Claim
25 words
A multilayer container according to claim 14, wherein said notch is a ring notch provided at a non-heat seal surface inside said heat seal portion.
Claim 20
Dependent Claim
45 words
A multilayer container according to claim 14, wherein a heat unfusible layer is provided on at least one surface of said flange portion and said lid member inside the heat seal portion and said notch is a ring notch provided inside said heat seal portion.
Claim 21
Dependent Claim
44 words
A multilayer container according to claim 14, wherein the layer structure of said inner surface layer and said another layer is a combination of (A) a resin mixture layer comprising a polypropylene base resin and a polyethylene base resin and (B) a polyethylene layer.
Claim 22
Dependent Claim
26 words
A multilayer container according to claim 19, wherein the weight ratio between said polypropylene base resin and said polyethylene base resin is from 50:50 to 97:3.
Claim 23
Dependent Claim
16 words
A multilayer container according to claim 19 wherein said polyethylene layer is a high density polyethylene.
Claim 24
Dependent Claim
28 words
A multilayer container according to claim 14, wherein said inner surface layer is a layer of a polyolefin resin and said another layer is a layer of metal.
Claim 25
Dependent Claim
31 words
A multilayer container according to claim 14, wherein said notch is provided at a non-heat seal surface of said inner surface layer at an inner peripheral portion of said flange portion.
Claim 26
Dependent Claim
26 words
A multilayer container according to claim 14, wherein another notch is further provided in an outer layer at an outer peripheral portion of said flange portion.
Claim 27
Dependent Claim
39 words
A multilayer container according to claim 14, wherein a rib or curl portion is provided at an outer end of the flange portion and a cut-off portion is provided at the rib or curl portion near the flange level.
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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) | 1993-03-05 | 1993-09-04 | 1994-03-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-03-05 | 1997-09-04 | 1998-03-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-03-05 | 2001-09-04 | 2002-03-06 | $7700.00 | Window Closed / Lapsed |