Sealing for paperboard containers

April 9, 1940.

2,196,243

D. BENSEL

SEALING FOR PAPERBOARD CONTAINERS

Filed March 27, 1937

<img file="US2196243A_D0001.tif" />

Patented Apr. 9, 1940

2,196,243

UNITED STATES PATENT OFFICE

2,196,243

SEALING FOR PAPERBOARD CONTAINERS

Duryea Bensel, New York, N. Y., assignor, by mesne assignments, to Albert Borden, New York, N. Y.

Application March 27, 1937, Serial No. 133,335

Claims. (CL 229—17)

The present invention relates to an improvement in paperboard containers, and more especially to containers for packaging liquids and flowable pulverulent materials.

&amp; The important feature herein is in the provision of means at the corners and score lines of the container whereby, when the carton is closed, the comers, folds and hinge scores of the closure are all rendered leak-, sift-proof and watertight. IQ In the present embodiment, the provision of means shown herein to accomplish the foregoing noted advantages, makes it possible to use a much thinner paperboard than is customary to use in cartons of this type, thus making for 15 greater economy in the use of materials, in the manufacture thereof.

The sealing element, as will be seen, is in the form of a strip or ribbon of paper, which is glued on the carton blank to overlie the main flap de20 fining score lines, which define all of the end closing flaps on each of said panels. It is a further advantage that the present sealing strip and its mode of attachment, permits its use on carton end-closures in which the flaps are cut25 scored from each other, or on end-closures in which the flaps are uncut, but are defined from each other by score lines.

The foregoing, and other features of advantage will be apprehended as the herein description 50 proceeds, and it will be obvious that modifications may be made in the structure herein without departing from the spirit of the invention or the scope of the appended claims.

In the drawing,

Fig. 1 is a plan view of the layout of a container blank partially broken away to save space;

Fig. 2 is a fragmentary perspective view of the container showing a scored, but uncut end closure;

Fig. 3 is a fragmentary, perspective view of another form of container end closure, comprising separate cut apart flaps;

Fig. 4 is an end view of Fig. 2, in reduced scale, showing the end closure of Fig. 2 sealed;

Fig. 5 is an end view, in reduced scale, of Fig. 3, in sealed end closure;

Fig. 6 is an enlarged, fragmentary, sectional view, taken on the line 6—6, Fig. 4, looking in the direction of the arrows; Fig. 7 is an enlarged ₆0 fragmentary sectional view taken on the line 7—7, Fig. 5, looking in the direction of the arrows.

Tn Fig. 1, the container blank comprises four main body forming panels A, B, C and D and a _cs body glue lap E, all defined from one another by score lines 19, 20, 21 and 22. The glue lap E has flap extensions 10 and T and these are defined from, their associate glue lap E by common score lines 29 and 30. Lap extension 10 is also defined from its associate end closure flap by a score line _B19, and lap extension T is defined from its associated end closure flap 4 by a cut score 4'.

Main body panels A, B, C and D, at their upper end as viewed in Fig. 1, have each uncut, end closure flaps 9, 10 and 11, respectively, all defined jq from said body panels by a common score line 29. Each of said end closure flaps 8, 9, 10 and I f are defined from one another by score lines 20, 21 and 22.

The end closure flap 8, Fig. 1, is provided with jg angularly disposed score lines 23—24 which extend inwardly from score lines 19 and 20 to the outer end of the flap 8, at which point they meet, forming two spaced apart diagonal sub-sections 12 and 13. ₂o

Flap 10 is similarly provided with angular score lines 26—27 forming two spaced apart diagonal sub-sections (6 and 17.

End closure flap II is provided with one diagonal score line 28, which extends from score 25 line 22 to the end of flap 11, at its marginal midportion, and forms a diagonal sub-section 18. Flaps 8, 10 and II are half or sub-flaps, that is, they are equal in length to one half of the dimension of the set-up container. ₃₀

Major end closure flap 9, is a full sized flap, and forms the main cover flap when over-folded on the sub-flaps, as indicated in Fig. 4.

Main flap 9 is provided with two angularly disposed score lines 25 and 31, line 25 extending from _3gscore line 21 to about the center of flap 9, and line 3 i extending in an opposite angular direction from the end of score line z5 and ends in the upper right hand corner of flap 9, as viewed in Fig. 1.

Sealing strip 3 is glued, as shown by the stip- .θ pling G, to the glue lap extension 10, and end closure flaps 8,9, 10 and 11, in such a manner that half of its width is free and extends beyond the outer ends of connected sub-flaps 9, 10 and II, but is fully glued to the major closure flap 9. ₄₆

Thus, the sealing strip 3 on the sub-flaps 8, 10 and 11 has half of its area arranged to freely overhang the edges of said sub-flaps.

As indicated at Fig. 1, the major flap 9 and a portion of the sealing strip 3 are provided with a ₆₀short, cut-score or perforated line S, which commences at the junction of the diagonal score lines 25 and 31 and ends at the sub-flap score line 21. The purpose of this line of weakening will be later described. 55

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The lower half of the container blank, as viewed in Fig. 1, is also provided with a sealing strip 2, and this is so glued, as to straddle the common score line 30, which defines the cut and scored 5 closure flaps 4, 5, 6 and 7 from the body panels A, B, C and D, and extends over and is glued to the glue lap extension T. Each of the flaps 4, 5, 6 and 7 and the glue lap T are independently foldable of each other on their common score line 10 30. Each of the flaps is provided with a pouring or filling aperture H, which, when the flaps are overfolded and sealed in container closing position, register with each other to form a common aperture, as indicated at H in Fig. 5.

The sealing strip 2, as indicated by the stippling G' is fully glued to the glue lap E, and to the extension T, and is partially glued to the flap 4 and the panel A, leaving a glue spot G' and two unglued spots F'—F'; the strip is fully glued to 20 the flap 5 and the panel B; and the flap 6 is provided with a glue spot G' with two unglued spots F'—F', while the strip portion on the panel C is fully glued and the strip is fully glued to the panel D and flap 7. These unglued portions on 25 the flaps 4 and 6 are located adjacent the cutscore edges of each flap and lap, and such portions being free, allows the unglued strip portions F—F to adjust themselves to the infolding action of the flaps, to be later described in detail.

The preferred material for these sealing strips is an extremely thin paper, such as featherweight or onion skin, which are not only thin but durable and tough. Such thin papers require a minimum of space between the overfolded closure 85 flaps and thus insure a true contact seal between said overfolded flaps.

In erecting and closing the container, the panels A, B, C and D are folded in the following order: glue lap E and its extensions are folded 40 over and down flat onto the panel A on score line IS. Then glue is applied to the exposed surface. Then the panels C—D are folded over upon score line 21 ,· forcing panel D and its flaps onto the glued glue lap E and its extensions.

After drying, the container is then brought to rectangular form by bending on the score lines 19, 20, 21 and 22.

Then the flaps 4, 5, 6 and 7, which are full sized flaps, are folded in the following order;

flap 7 may be first closed in, Fig. 3, then flap 5 is glued and folded down upon 7, -this action, as indicated in Fig. 3, pulls down the four gluefree sections F—F, and F—F of strip 2 into natural angular corner folds F—F, Fig. 3, with 55 the remaining portion of the strip 2 adhered to flaps 6 and 4. Then the flaps 4 and 6 are glued and folded down, causing the adherent strip portions thereon to lie in face contact with the next successive index flaps, Fig. 6, at L. As these 50 flaps are in full glued contact with each other, as folded, it is obvious that a fully closed contact is effected between the flaps and the sealing strip sections, and makes the scores and comer jointures sift- and leak-proof.

This last described end closure, may form a bottom filler closure for the present container and the aperture H to be closed with a closure cup such as is set forth in my pending patent application, Serial #758,820, filed December 22, 70 1934, Figs. 5 to 11. This end closure may also be used as a filling and sealed pouring closure for fluid holding or similar containers, and sealed as disclosed in Figs. 10 and 11.

In the upper closure, as viewed in Fig. 1, the 75 closure flaps 8, 9, 10 and II are all connected to one another, the scoring, straight and angular being so arranged as to permit of the flaps S and 10 to be angularly infolded, in closing, as indicated in Fig. 2, such infolding causing the simultaneous drawing in, to closing position, of b the two flaps 11 and 9, flap I i closiiig in on top of flaps 8 and 10 and their under sub-flaps 12—13, 16 and 17, and flap 9 finally closing down on flap 11 and being adhered thereto to form an outer cover closure. This closure is 10 similar to that disclosed in my pending patent application, Serial #116,053, filed December 16, 1936, Figs. 1 and 10, with the exception of the herein described sealing strip 3.

In the folding down of the flaps 8, 9, 10 and 15 11, as above described, the overhanging unglued extension of strip 3, is automatically positioned sequentially from that shown in Fig. 2, to the position shown in Fig. 6, the said unglued extension and flaps taking the positions as shown in 20 said figure at V and the final closure folds said portions V of strip 3 down flat upon the under flaps 8—II, 12 and 13, leaving the various folds V in contact with one another, in adhered relation. When this closure is opened as will be 25 pointed out in, detail later, the unglued position of strip 3 is tom at the line of weakened resistance S.

With the closure so formed, the main top closure flap 9, when glued down, then presents the 30 perforated line of weakness S, best seen in Fig. 4. This closure, like the one previously described, is leak- and sift-proof.

To open this closure to pour out the contained material, the perforated line of weakness on the M cover 9 is broken, to the center of the cover, the two double triangular connected flaps 25 and 31 on each side of the break, being bent backwardly on the score lines 26—27 this action exposing the underlying triangular flap 10 and its 45 two triangular sub-flaps 16 and 17.

Then the flap 10 and its appurtenant triangular sub-flaps 16—17 with triangular subflaps 14 and 18 are pulled upwardly and outwardly and thereby form a reclosable, extended 55 pouring spout. During this opening action, the weakened line S on the sealing strip 3, Fig. 1, is torn, the extending edge of the strip beyond the edge of flap 10, having been adhered to the extending strip portion on flap 11 and its sub-flap 55 18, which extending portion, is itself adhered flat on top of flap 11 and its sub-flap 18.