Patent US3913826A successfully refreshed from Google Patents.
US3913826A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Leak proof bottom for a paperboard container
Assignee: International Paper Co
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Filing: 1973-07-12
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Granted: 1975-10-21
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Expires: 1993-07-12
Abstract
Abstract Disclosed is an improved bottom closure for a paperboard container of the type commonly used to package milk. The improvement specifically relates to the blank from which the container is formed. When a container is formed from a blank which embodies this improvement, leaks in the bottom closure thereof are substantially prevented.
Inventors
- 👤 Milton A Brownlee
- 👤 Thomas A Tomlin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 12:56
CPC Classifications
B; B65; B65D; B65D5/00; B65D5/02; B65D5/06; B65D5/064
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
218 words
In combination with a thermoplastic coated paperboard blank adapted to be erected to form a square, heat sealed container, said blank having a body forming portion and a bottom forming portion, said bottom forming portion including two spaced apart gusset forming flaps having substantially aligned transverse edges and forming gusset points when said blank is erected, a cover flap foldably connected by a longitudinal fold line to at least one of said gusset forming flaps, and a tuck-in flap foldably connected by a longitudinal fold line to at least one of said gusset forming flaps, the improvement which comprises: a. at least the center portion of the transverse edge of said tuck-in flap being substantially aligned with the transverse edges of said gusset forming flaps and the remainder of the edges of said tuck-in flap disposed to entirely underlie said gusset forming panels when said blank is erected; and b. a thermoplastic film patch bonded to at least one of said flaps adjacent to the center of the transverse edge thereof and extending beyond the transverse edge of said gusset forming flaps whereby, when said blank is erected and heat sealed to form a container, both said gusset points and the center portion of the transverse edge of said tuck-in flap are sealed by said thermoplastic film patch.
Claim 2
Dependent Claim
218 words
In combination with a thermoplastic coated paperboard blank adapted to be erected to form a square, heat sealed container, said blank having a body forming portion and a bottom forming portion, said bottom forming portion including two spaced apart gusset forming flaps having substantially aligned transverse edges and forming gusset points when said blank is erected, a cover flap foldably connected by a longitudinal fold line to at least one of said gusset forming flaps, and a tuck-in flap foldably connected by a longitudinal fold line to at least one of said gusset forming flaps, the improvement which comprises: a. at least the center portion of the transverse edge of said tuck-in flap being substantially aligned with the transverse edges of said gusset forming flaps and the remainder of the edges of said tuck-in flap disposed to entirely underlie said gusset forming panels when said blank is erected; and b. a thermoplastic film patch bonded to at least one of said flaps adjacent to the center of the transverse edge thereof and extending beyond the transverse edge of said gusset forming flaps whereby, when said blank is erected and heat sealed to form a container, both said gusset points and the center portion of the transverse edge of said tuck-in flap are sealed by said thermoplastic film patch.
Claim 3
Dependent Claim
24 words
The blank of claim 1 wherein a thermoplastic film patch is bonded to each of said gusset forming flaps and overlies said gusset points.
Claim 4
Dependent Claim
19 words
The blank of claim 2 wherein said blank is coated with polyethylene and said thermoplastic film patch is polyethylene.
Claim 5
Dependent Claim
11 words
The blank of claim 2 wherein said tuck-in flap is notched.
Claim 6
Dependent Claim
13 words
The blank of claim 4 wherein said notch has parallel, longitudinal side edges.
Claim 7
Dependent Claim
21 words
The blank of claim 5 wherein said thermoplastic patch has a melt index in the range of approximately 3.0 to 300.
Claim 8
Dependent Claim
12 words
The blank of claim 4 wherein said notch has divergent side edges.
Claim 9
Dependent Claim
21 words
The blank of claim 7 wherein said thermoplastic patch has a melt index in the range of approximately 3.0 to 300.
Claim 10
Dependent Claim
21 words
The blank of claim 2 wherein said thermoplastic film patches are bonded to the interior surface of said gusset forming flaps.
Claim 11
Dependent Claim
35 words
The blank of claim 1 wherein said thermoplastic film patch is bonded to the interior surface of said tuck-in flap and overlies the center portion of said tuck-in flap adjacent to the transverse edge thereof.
Claim 12
Dependent Claim
226 words
IN combination with a thermoplastic coated paperboard blank adapted to be erected to form a heat sealed container, said blank having a body forming portion and a bottom forming portion, said bottom forming portion including two spaced apart gusset forming flaps having substantially aligned transverse edges and forming gusset points when said blank is erected, a cover flap foldably connected by a longitudinal fold line to at least one of said gusset forming flaps, and a tuck-in flap foldably connected by a longitudinal fold line to at least one of said gusset forming flaps, the improvement which comprises: a. at least the center portion of the transverse edge of said tuck-in flap being cut so as to be aligned with said gusset points when said carton is formed and the remainder of the edges of said tuck-in flap disposed to entirely underlie said gusset forming flaps when said blank is erected; and b. two thermoplastic film patches; each bonded to a respective one of said gusset forming flaps so as to overlie said gusset points and each of said patches extending beyond the transverse edge of said gusset forming flaps whereby, when said blank is erected and heat sealed to form a container, both said gusset points and the center portion of the transverse edge of said tuck-in flap are sealed by said thermoplastic film patch.
Claim 13
Dependent Claim
226 words
IN combination with a thermoplastic coated paperboard blank adapted to be erected to form a heat sealed container, said blank having a body forming portion and a bottom forming portion, said bottom forming portion including two spaced apart gusset forming flaps having substantially aligned transverse edges and forming gusset points when said blank is erected, a cover flap foldably connected by a longitudinal fold line to at least one of said gusset forming flaps, and a tuck-in flap foldably connected by a longitudinal fold line to at least one of said gusset forming flaps, the improvement which comprises: a. at least the center portion of the transverse edge of said tuck-in flap being cut so as to be aligned with said gusset points when said carton is formed and the remainder of the edges of said tuck-in flap disposed to entirely underlie said gusset forming flaps when said blank is erected; and b. two thermoplastic film patches; each bonded to a respective one of said gusset forming flaps so as to overlie said gusset points and each of said patches extending beyond the transverse edge of said gusset forming flaps whereby, when said blank is erected and heat sealed to form a container, both said gusset points and the center portion of the transverse edge of said tuck-in flap are sealed by said thermoplastic film patch.
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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) | 1978-10-20 | 1979-04-21 | 1979-10-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-10-20 | 1983-04-21 | 1983-10-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-10-20 | 1987-04-21 | 1987-10-21 | $7700.00 | Window Closed / Lapsed |