Envelopes – wrappers – and paperboard boxes – Paper or paperboard cup
Reexamination Certificate
2002-02-01
2003-12-16
Elkins, Gary E. (Department: 3727)
Envelopes, wrappers, and paperboard boxes
Paper or paperboard cup
C229S005500
Reexamination Certificate
active
06662996
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention relates to the field of leakproof paper cups and the making thereof.
Volume production of paper cups and plastic coated paper cups has achieved considerable success in the United States of America and abroad. One deficiency inherent in the cups formed using a layer of insulating foam is that the leak rate per million cups is almost double when compared to cups formed using plain paper stock. However, insulating foam cups have proven to be very popular. An unsolved problem is how to produce a better bottom seam seal for insulating foam cups since most of the leaks occur where the side seam adjoining a lower cylindrical portion of the cup attaches to the bottom blank.
FIG. 1A
shows a cross section of a prior art cylindrical cup
100
. The peripheral wall
150
of cup
100
has its lower edge
160
curved inwardly and upwardly forming a channel.
The circular bottom blank
110
is typically a single layer of board and has a downwardly extending skirt
120
formed about its periphery.
FIG. 1A
also shows where the prior art applies heat to seal the bottom blank
110
to the peripheral wall
150
. Heat is applied at
130
to the interior of the shallow hollow formed below the ascending sidewall
140
and the bottom blank
110
.
FIG. 1B
shows a more detailed cutaway of an X-point
180
where five layers of board come together. The X-point
180
is especially prone to leaks.
Typically, a single layer of board is shaped to form a peripheral wall
150
of a cup
100
. The two edges of the peripheral wall board meet and overlap to form a side seam
170
. The side seam
170
is created by overlapping the two edges of the board and sealing them together. Because the board is overlapped to form the side seam
170
, the side seam
170
is two layers thick. Because the peripheral wall
150
has its lower edge
160
curved inwardly and upwardly to form the channel, a double layer of the peripheral wall
150
is thus also curved inwardly and upwardly at the seam
170
.
At all points where the peripheral wall
150
meets the bottom blank
110
, except at the X-point
180
, there are three layers of board. To seal the peripheral wall
150
to the bottom blank
110
, the heat must penetrate two layers of board. The two layers of board are the peripheral wall's
150
single layer and the bottom blank's
110
single layer.
But, at the X-point
180
is where side seam
170
meets the periphery of bottom blank
110
, the side seam
170
is four layers thick, two layers on the outside and two layers on the inside where the side seam
170
is folded upward. When the bottom blank
110
is then coupled to the top blank, the X-point
180
becomes five layers thick. To seal at the X-point
180
, the heat must penetrate three layers of board. The three layers of board are the side seam's
170
two outer layers and the bottom blank's
110
single layer.
BRIEF SUMMARY OF THE INVENTION
The present invention provides a cup less likely to leak by forming a u-shaped channel about a periphery of a bottom blank, forming a top blank into a generally cylindrical shape, and coupling an edge of the top blank to the u-shaped channel of the bottom blank.
REFERENCES:
patent: 2611154 (1952-09-01), Chevrier
patent: 3137431 (1964-06-01), Crouse et al.
patent: 3157339 (1964-11-01), Negoro
patent: 3164314 (1965-01-01), Waycie
patent: 3322045 (1967-05-01), Tanona
patent: 3439590 (1969-04-01), Rosenberg et al.
patent: 3547012 (1970-12-01), Amberg et al.
patent: 3855908 (1974-12-01), Schmidt et al.
patent: 3949927 (1976-04-01), Smith et al.
patent: 3973316 (1976-08-01), Maher
patent: 4127059 (1978-11-01), Richards
patent: 4168676 (1979-09-01), Itoh
patent: 4187768 (1980-02-01), Suzuki
patent: 4211339 (1980-07-01), Itoh
patent: 4222974 (1980-09-01), Smith
patent: 4373928 (1983-02-01), Horton
patent: 4428741 (1984-01-01), Westphal
patent: 4430142 (1984-02-01), Ochi et al.
patent: 4435344 (1984-03-01), Iioka
patent: 4757936 (1988-07-01), Homma et al.
patent: 4836400 (1989-06-01), Chaffey et al.
patent: 5363982 (1994-11-01), Sadlier
patent: 5431619 (1995-07-01), Bacon et al.
patent: 5490631 (1996-02-01), Iioka et al.
patent: 5725916 (1998-03-01), Ishii et al.
patent: RE35830 (1998-06-01), Sadlier
patent: 5766709 (1998-06-01), Geddes et al.
patent: 5840139 (1998-11-01), Geddes et al.
patent: 5993705 (1999-11-01), Grishchenko et al.
patent: 6030476 (2000-02-01), Geddes et al.
patent: 6129653 (2000-10-01), Fredricks et al.
patent: 6139665 (2000-10-01), Schmelzer et al.
patent: 6142331 (2000-11-01), Breining et al.
patent: 6308883 (2001-10-01), Schmelzer et al.
patent: 6319590 (2001-11-01), Geddes et al.
patent: 6328557 (2001-12-01), Grishchenko et al.
patent: 819036 (1951-10-01), None
patent: 383003 (1931-10-01), None
patent: 5-147639 (1993-06-01), None
Elkins Gary E.
Fulbright & Jaworski LLP
Georgia-Pacific Corporation
LandOfFree
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