U.S. patent number 3,692,226 [Application Number 05/045,507] was granted by the patent office on 1972-09-19 for removable side wall for tightly sealed drumhead cartons.
This patent grant is currently assigned to Riegel Paper Corporation. Invention is credited to William H. Watson, Chauncey Young.
United States Patent |
3,692,226 |
Young , et al. |
September 19, 1972 |
REMOVABLE SIDE WALL FOR TIGHTLY SEALED DRUMHEAD CARTONS
Abstract
An improved opening arrangement for dispensing the contents of a
hermetically sealed drumhead carton is disclosed herein. A totally
removable side wall panel is included in the carton, and its
removal is facilitated by an integral lift tab formed in a
contiguous dust flap in the end closing structure. The lift tab is
arranged and pre-cut so that it may be readily grasped and removed
along with the side wall panel to provide an open sided carton,
without disturbing either of the drumheads, for "eat-from-box;"
"mix-in-box;" "grow-in-box;" "heat-in-box" product
applications.
Inventors: |
Young; Chauncey (St. Louis,
MO), Watson; William H. (St. Louis, MO) |
Assignee: |
Riegel Paper Corporation (New
York, NY)
|
Family
ID: |
21938287 |
Appl.
No.: |
05/045,507 |
Filed: |
June 11, 1970 |
Current U.S.
Class: |
229/240;
229/125.34 |
Current CPC
Class: |
B65D
5/725 (20130101) |
Current International
Class: |
B65D
5/72 (20060101); B65d 005/54 (); B65d 005/08 () |
Field of
Search: |
;229/17R,7,37,51TS,51R,51D,51C,14BA,14BL |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Leclair; Joseph R.
Assistant Examiner: Marcus; Stephen
Claims
We claim
1. An end sealed carton fabricated from sheet material including a
paperboard layer, comprising
a. a carton body having consecutively articulated first side, front
wall, second side, and rear wall panels;
b. first and second dust flaps articulated to the ends of each of
said side wall panels along first and second hinge lines;
c. end flaps articulated to the ends of each of said front and rear
wall panels along hinge lines;
d. a pair of sealing membranes having parallel side edges;
e. means strongly bonding said membranes to the inner surfaces of
all of said flaps to close off the ends of said carton;
f. major portions of the side edges of said second side wall being
defined by vertical lines of severance;
g. a pre-cut tab contiguous with said opening panel and defined
within said second dust flap;
h. beveling lines of severance connecting the ends of said lift tab
with said vertical lines of severance.
2. The carton of claim 1, further characterized in that
a. said end flaps have relieved portions adjacent said second dust
flap;
b. said relieved portions are sufficient to provide access to said
lift tab when said second dust flap is infolded and said end flaps
are infolded over said infolded second dust flap.
3. The carton of claim 1, further characterized in that
a. a membrane is sealed to said second dust flap only along inboard
portions thereof.
4. The carton of claim 1, in which
a. a major portion of the bottom edge of said second side wall is
defined by a horizontal line of severance.
5. A one-piece paperboard blank for an end-fillable carton adapted
to be end sealed with a membrane of predetermined width,
comprising
a. first side wall, front wall, second side wall, rear wall, and
glue flap panels consecutively articulated along parallel. vertical
score lines;
b. first and second dust flaps articulated to the ends of said side
wall panels along first and second horizontal fold lines;
c. first and second end flaps articulated to the ends of said front
and rear wall panels along horizontal score lines;
d. major portions of the side edges of said second side wall being
defined by vertical lines of severance;
e. a pre-cut lift tab of less than full carton depth contiguous
with said opening panel and defined within said second dust
flap;
f. beveling lines of severance connecting the ends of said lift tab
with said vertical lines of severance;
g. said end flaps having relieved portions adjacent said second
dust flap; and
h. said relieved portions being sufficient to provide access to
said lift tab when said second dust flap is infolded and said end
flaps are infolded over said infolded second dust flap.
6. The blank of claim 5, further characterized in that
a. a major portion of said bottom edge of said second side wall is
defined by a horizontal line of severance.
Description
BACKGROUND OF THE INVENTION
Many airtight, siftproof, and moistureproof paperboard carton
constructions for liquid and pulverulent materials are formed from
parallelpiped cartons and have their opposite ends tightly sealed
by "safety shield" members or "drumhead" membranes adhered to the
carton end flaps and side flaps (dust flaps). Presently, in
commercially useful drumhead cartons, the membrane material and/or
the inner surfaces of the flaps to which the membranes are adhered
are thermoplastic. For example, a resin, wax or other material
which may be easily heat sealed may be coated on the membrane or
flaps. The strength of these drumhead cartons is often custom
tailored to meet packaging requirements by the choice of laminated
materials used to construct the blanks. Moreover, with the
development of improved coated and laminated paperboard materials
and improved thermoplastic films, the tightness and imperviousness
of membrane sealed cartons of the aforementioned type have been
greatly improved, and these cartons have continued to find ever
increasing acceptance and widespread use in diverse packaging
applications. Ironically, however, the vastly improved strengths of
the heat seal bonds of the thermoplastic membranes to the carton
flaps, while offering increased packaging protection, have often
introduced serious opening problems for the ultimate consumer.
Accordingly, it is to one solution of these opening problems that
the present invention is directed.
SUMMARY OF THE INVENTION
In membrane sealed cartons erected from laminated or plastic coated
paperboard blanks, the cartons may, of course, be opened and access
to the contents may be had by puncturing the membrane or by peeling
it from the carton body. However, this is extremely difficult and
often impossible due to the integrity and high strength of the heat
seal bond between the membrane material and the flaps. Where the
carton is a thermoplastic coated foil laminate, for example,
peeling removal of the entire thermoplastic or thermoplastic coated
membrane is strenuously resisted by the strong and hard bonding of
the membrane to the flaps. Accordingly, effecting a delamination of
the entire membrane is extremely difficult.
In accordance with the principles of the present invention, access
to the contents of the drumhead carton is obtained through an
entire side of the carton without disturbing or disrupting the
membrane. This is accomplished by removing the entire side wall
along pre-scored lines of severance. The corners of the opening
side wall are beveled to optimize the facility of its removal.
Moreover, an integral pre-cut lift tab is included in the dust flap
which is contiguous with the opening side wall panel, which, as
previously mentioned, is defined by lines of weakness or severance
which do not penetrate carton material and do not effect
permeability. In this manner, a hermetically sealed carton or the
like may be economically constructed, since the cuts in the dust
flap which define the lift tab will be sealed by the drumhead
membrane. Moreover, to provide a consumer with easy access to the
starting lift tab defined in the dust flap, those portions of the
carton end flaps which tend to overlie the starting tab are cut
back or relieved to expose the starting tab.
For a better understanding of the present invention and its
attendant advantages, reference should be made to the following
detailed description taken in conjunction with the accompanying
drawings.
DESCRIPTION OF DRAWINGS
FIG. 1 is a plan elevational view of a drumhead carton blank from
which a carton embodying the principles of the invention may be
fabricated;
FIG. 2 is a perspective view of a sealed carton embodying the
principles of the invention; and
FIG. 3 is a fragmentary, perspective view of the carton of FIG. 2
with the opening panel partially removed.
FIG. 4 is a perspective view of the carton of the invention showing
the application of the sealing membrane; and
FIG. 5 is an enlarged, fragmentary, cross-sectional view of the
carton of the invention showing the relationship of the membrane to
the infolded flaps.
DESCRIPTION OF PREFERRED EMBODIMENT
Referring to Fig. 1, a blank 10, from which the carton of the
invention may be erected, is advantageously a paperboard sheet
material having a heat sealable coating such as polyethylene on the
inner surface (in terms of the erected carton). The blank includes
contiguous first side, front, removable second side, and rear wall
panels 11-14, respectively, a glue flap panel 15 consecutively
articulated along score lines 16-19. End flaps 20-23 are
articulated to the front and rear wall panels 12, 14 along
horizontal score lines 24, 25, as shown. A pair of dust flaps 26,
27 are articulated to the first side wall panel 11 along the
horizontal score lines 24, 25. A pair of second dust flaps 28, 29
are articulated to the second side wall along the horizontal score
lines 24, 25. As shown, all of the carton flaps are separated from
one another by cuts 30. In accordance with the invention, the side
wall 13 is readily severable from the blank by the further
weakening of its scored edges by cut scores 17', 18' and 25' which
do not fully penetrate the blank.
As an important aspect of the present invention, the removable wall
panel 13 has an integral lift tab 32 hinged thereto. The tab 32 is
formed at the juncture of the side wall 13 with its dust flap 28.
As shown, the lift tab 32 is completely defined by an arcuate cut
33 and the horizontal score line 24, while the removable opening
wall panel 13 is defined by the non-penetrating lines of weakness
17', 18' 25' and beveling lines of weakness 40 and 41,as shown. In
addition, end flaps 20, 22 are appropriately cut back or relieved,
as shown at 35. The shape of the relieved edges 35 of the end flaps
20, 22 is sufficient to define an access opening 36 when the flaps
20, 22 are subsequently infolded over the dust flap 28 in carton
formation. The access opening 36 will expose substantially all of
the cut 33 for easy grasping of the lift tab 32 by a consumer.
In accordance with the invention, an easily openable membrane end
sealed carton 50 is fabricated from the blank 10 as follows: The
blank is first formed into a collapsed carton tube by folding
panels 14, 15 about the score line 18, then folding side wall panel
11 about the score line 16, and finally gluing or otherwise
suitably adhering the underlying glue flap 15 to the overlying side
wall panel 11. As will be understood, the flattened tubes may be
economically and conveniently shipped from the manufacturer to the
packaging plant where they are to be squared and filled.
Preparatory to filling, the carton tube is squared and then the
bottom side or dust flaps 27, 29 and bottom end flaps 21, 23 are
outfolded into a horizontal plane. Thereafter, the sealing or
drumhead membrane 51 is heat sealed to the outfolded flaps. The
bottom end closure is then completed by infolding the dust flaps
27, 29 then infolding the end flap 23; infolding the flap 21 and
finally, suitably securing by adhesive or otherwise the outboard
portion 21 of the flap 21 to the outboard portion of the underlying
flap 23. At this stage, the carton may be filled with a liquid,
semi-liquid, granular or pulverulent material or the like, through
the open top end after which the top end is sealed with another
membrane 51 and completed in the identical manner as that described
for the bottom end.
Opening of the carton, in accordance with the principles of the
invention, may be effected simply and efficiently in the following
manner. The lift tab 32, which is exposed through the opening 36,
as shown in Fig. 2, is grasped and pulled upwardly and outwardly by
the user, thereby separating the removable side panel 13 from the
carton and defining a dispensing opening 52 of substantially full
carton side wall dimensions. Advantageously, the open corners of
the carton are strengthened by triangular webs 55 which are formed
by virtue of the beveling lines 40, 41, which themselves facilitate
the tearing removal of the panel 13. The webs 55 are particularly
advantageous where the opened carton is used with its contents such
as in "eat-in-box," "bake-in-box," "mix-in-box," and "grow-in-box"
type applications. Since a portion of the membrane 51 will have
been sealed to the dust flap 28 during carton formation, the
grasping and pulling of the lift tab, during opening, will separate
the pre-cut lift tab from the membrane by delamination (either
within the strata of the laminated paperboard stock, itself, or
along the membrane-flap interface). Regardless of the nature of the
delamination of the lift tab 32 from the membrane 51, such
delamination will be greatly facilitated and expedited by limiting
the area of the lift tab which is heat sealed to the membrane 51.
To that end and as an important aspect of the invention, the area
of bonding of the membrane to the lift tab is restricted to an
inboard portion of the lift tab, advantageously a narrow zone 53
(Fig. 3) immediately adjacent the score line 24 so that the
outboard end 54 of the lift tab is unbonded from the membrane 51.
In this manner, and as will be appreciated, the lift tab 32 may be
easily separated from the dust flap 28 and underlying membrane 51
to start the tear opening of the panel 13 along the score line
34.
It should be understood that the specific carton herein illustrated
and described is intended to be representative only, as certain
changes may be made therein without departing from the clear
teachings of the disclosure. Accordingly, reference should be made
to the following appended claims in determining the full scope of
the invention.
* * * * *