US2423804A - Method of making lined cartons - Google Patents

Description

July 8, 1947.

H. F. WATERS METHOD oF MAKING LINED cARToNs original Filed May 15, 1941 2 Sheets-Sheet 1 IN VENTOR.

HTToR/YEY HHRRYF WHTERS y1/Mx@ W 'l l i l July 8, 1947. H. F. WATERS METHOD oF MAKING LINED cARToNs 2 Sheets-*Sheet 2 Original Filed-May 15, 1941 v I lNvENToR.

H/Ry/TWHTERS HTTORNY' Patented July 8, 1947 UNITED STATES PATENT OFFICE 2,423,804 Y METHOD OF MAKING LINED CARTONS HarryF. Waters, New York, N. Y.

Original application May 13, 1941, Serial No. 393,171.y Divided and this application May 11, 1942, Serial No.'442,530

This invention relates to a method f making a lined carton.

This application is a division of my application Serial No. 393,171, iiled May 13, 1941, for Method of making containers and products thereof.

It is within the contemplation of the present invention to provide a novel method of forming duplex containers having an outer four-sided carton and an inner tubular liner which involves a few and simple operations and which may be readily carried out on a practical and indii-Jistrial scale at a high speed and at a low cos It is a further object of the invention to provide flexible sheet material containers substantially continuously by applying adhesive to the longitudinal marginal portions of a sheet and in which the transverse seams are formed by the application of heat and pressure to predetermined transverse strips of the tubular structure so formed.

Fig. 1 illustrates a top elevational view of a carton blank having a liner attached thereto and embodying some of the principles of the present invention;

Fig. 2 is a transverse sectional view taken on line 2-2 of Fig. 1; v Y

Fig. 3 shows the carton blankyand attached liner in the next stage of their conversion into a lined tubular carton;

Fig. 4 is a transverse section taken on line. 4-4 of Fig. 3;

Fig. 5 illustrates the carton blank and the liner converted into a duplex tubular form;

Fig. 6 depicts a transverse sectional view taken on line 6-6 of Fig. 5;

Fig. 7 is a similar View of the tubular container after its erection;

Fig. 8 is a perspective view of the upper portions of the lined container in the erected condition preparatory to filling and to forming the top'seal;

. Fig. 9 is a similar view showing the mouth portions of the liner attened down into the plane defined by the hinge lines of the top flaps;

Fig. 10 is a similar perspective view of the top portions of the container after it has been iilled with the commodity to be packaged and after its mouth portions have been folded into sealing position;

Fig. 11 is a perspective representation of the resulting package after the tabs resulting from -the top seam have been folded inwardly within the space dened by the body of the carton;

4 claims. (c1. eis-36.01)

Fig. V12 is a. perspective view of the package with'thetop end flaps closed and the front and rear flaps open; and

Fig. 13 is a similar view of the top portions of the completed package.

Broadly stated, according to the principles of my invention, I depart from the practice ci employing only an adhesive or only the application of heat and pressure for forming a substantially duid-tight or moisture-proof container. Asthose skilled in the art know, heretofore inthe quantity production of moisture-proof containers generally an adhesive of suitable character Was applied to predetermined marginal regions of a sheet or strip in order to form a Seam in such regions by means ofthe adhesive. Another procedure practiced on large scale with flexible sheets constituted of a heat-fusible material on at least vone face thereof involved bringing the corresponding marginal portions of the sheet into face to face position and then applying heat and pressureV to such region whereby the fusible material formed a strong bond between the said marginal portions. Both of these prior practices had certainl inherent disadvantages in that by the exclusive use of an adhesive it was difficult, if not impossiblato obtain a hermetic seal while, when heat sealing has been resorted to, it was difficult to obtain high operating speeds due to the fact that a relatively long time had to be allowed for satisfactory fusion of the thermoplastic material and for its subsequent cooling, which was necessary prior to further handling.

I havey discovered that excellent results may be obtained by combining an adhesively secured seam with heat sealed seams in the manufacture of flexible-walled containers, provided that a certain critically important relationship is maintained between the adhesive employed and the thermoplastic material employed. Thus, for example,I have found that in forming a moistureproof orfluid-tight container from sheet material it is-A very advantageous to form the longitudinal seam by means of an adhesive which may be applied in a liquid or heat-fused condition and which exerts its adhesive effect immediately after its application. Preferably, the adhesive is c0nstituted of a material which is fusible or thermoplastic after drying. At present a large number of such adhesives are known, examples of which are a rubber hydrochloride product known under the name Pliolm, a vinyl resin known under the name Vinylite, and the like. Similar results may be obtained by means of a thermoplastic adhesive materal known under the name Koroseal which 'I understand to be a vinyl chloride compound. All of these materials constitute excellent and quickly drying adhesives when they are brought into a viscous condition by means of heat fusion or by means of dissolving in a suitable solvent. Accordingly, the preferred form of my method involves the conversion of a continuous strip of material having a huid-tight or thermoplastic coating on one face thereof by applying such adhesive to the longitudinal marginal portions of the sheet and by pressing such portions together. Due to the rapid cooling or drying of the adhesive, a tube having a continuous iiuidtight and thermoplastic inner surfacev 1 will be formed and this tube may be separated into :lndividual bags by applying a heated transverse bar at spaced intervals thereto and subsequently severing such bags from the tube. I have found that in most cases it is desirable to employ the same material for the adhesive as for the coating of the sheet so that the dried adhesive may be fused and heat sealed substantially by the same degree of heat and pressure as the other portions of the sheet. Of course, it will be readily appreciated that the bags thus formed may be combined with a reinforcing carton either before, during or after the formation of the bag itself, as this will be explained morev fully hereinafter.

Figs. 1 to 3 illustrates the application of the principles of the present invention to the production of afour-sided carton having a fluid-tight flexible-Walled bag therein. In Fig. 1 is shown a four-sided carton blank 50 having front and rear panels 5l and 52 and having two end panels 53 and 54. Panels 5I and 52 have top closure flaps 55 and 56 and bottom closure flaps 51 and 58 associated therewith and end panels 53 and 54 have top closure aps 59 and 60 and bottom closure flaps 6| and 62 hingedly connected thereto. 'Ihe carton blank is provided with conventional longitudinal score lines 45, 46, 41 and 48 and with conventional transverse score lines 49. A glue iiap 65 is hingedly connected to panel 52 and is continued by means of tabs or ears 56 which are hingedly Aconnected to top and" bottom closure flaps 56 and 58, respectively.

To the carton blank described is attached a liner 10 constituted of flexible material which is fusible and fluid-tight on at least the top surface thereof, such as, for example, paper coated with a suitable fluid-tight and thermoplastic material. Of course, a flexible sheet constituted of integrally thermoplastic material may be likewise employed with equal or similar results. This liner sheet has dimensions closely approximating those of the carton blank and is attached thereto by means of lines of adhesive 1| provided on the various panels 5| to 54 so that the liner willfollow the movement of the carton blank during the subsequent folding operations. As it will be best observed in Fig. 2, liner 10 is so attached to blank 50 that its right hand edge slightly protrudes beyond the carton blank.

The rst step in converting blank 59' and liner 10 into a container includes folding carton on score line 41. Hereafter, the protruding portion 13 of the liner is folded back along the edge of glue flap B5 and tabs 66 and is attached thereto by means of spots of adhesive 15. This structure Will be readily observed in Figs. 3 and 4.

The next operation involves folding carton and liner along score line 45 and applying a suitable quick drying adhesive which is thermoplastic upon drying to the top surface ofthe Yfolded back portions of the liner. This folding operation will bring the two longitudinal marginal strips of the liner into cooperating contacting position whereby the adhesive applied thereto may take effect and will firmly bond these regions together and form a longitudinal seam. At the same time the left hand marginal strip of end panel 53 may be attached to the corresponding portion of glue flap 65 by means of glue, or some other suitable adhesive. These operations will convert carton blank 5E) and liner sheet 19 into a four-sided tubular carton with a four-sided tubular liner, the latter having a completely fluid-tight and fusible inner surface. The finished structure of this collapsed tubular container will be best seen in Fig. 6 v which clearly shows that the liner forms a complete tubular structure the closures of which are independent from those of the carton.

Otherl important properties of this structure will appear in Fig. 7 which is a cross-sectional view taken across the tubular carton and liner after it has been erected. From Fig. '7 it is apparent that the main fold line 19 of the longitudinal seam of the tubular liner is placed in the medial line of end panel 53 and that the longitudinal seam of the liner is flattened in the plane of such panel. This circumstance is of great importance during the subsequent operations required for forming the bottom closure and the top closure of the liner. It is also Worth noting that the region ofadhesion in the longitudinal seam of the liner generally denoted by reference character 18 is spaced from fold line 19 of the liner whereby a slip joint structure of desirable characteristics is obtained,'as it is set forth more fully in my co-p'ending application Serial No. 260,708, led March 9', 1939. This slip joint makes it possible for the inner tubular liner to expand under the effect of internal pressure and to pay out excess material incorporated therein whereby full support ofthe liner material by the considerably stro-nger carton walls is assured under all operating conditions. This operation provides a collapsed four-sided carton with a four-sided tubular liner which may be shipped or stored in the collapsed condition, shown in Fig. 5, and is ready for its ultimate use.

When it is desired to package commodities into this container,A the preferred procedure followed is to rst square up or erect the collapsed carton and thereby simultaneously to erect the tubular liner, which obviously follows all movements of the carton panels. Hereafter, the bottom of the tubular liner is sealed b-y the application of heat and pressure to a transverse zone thereof and is folded into the body ofthe carton and the bottom flaps of the carton are closed thereabout. Thus, the tubular liner has been converted into a bag with an open filling opening. This bag may know be lled with the commodity to be packaged and after filling, the mouth opening may be likewise sealed and the top aps may be closed thereabout in a similar manner. In View of the fact that the procedure followed in forming the top and bottom closures of the liner are identical, in the following only formation of the top closure will be described.

Fig. 8 illustrates the upper portions of the lined carton in the erected condition thereof. In this condition the liner may be filled with a deter'- mined amount of the commodity to be packaged through a suitable lling device diagrammatcally shown by a filling spout 80. In this condition of the erected container, tab 66 hingedly connected to top nap 56 is located between the body of the liner and the longitudinal seam 8|. Hereafter, all top closure aps'55, 56,59 and 60 are folded away from the upper portions of the 'liner in order to facilitate manipulation thereof. Folding away of top closure flap 56-Will pull out tab 65 from-'its former position and leave the mouth portions of the liner completely free for subsequent operations. In forming the top closure seam, the upper portions of the liner are flattened linto the planedened by the hinge lines of the top closure flaps so thatall of the mouth portions 'are'. brought into a single plane including the upper end of longitudinal seam 8|. This condition is illustrated in Fig. 9. It will be readily observed in this gure that the flattened mouth vportions contain only two layers of material brought into face to face position and that intervening and doubled up layers are completely absent from this structure. Heat and pressure may be applied to a transverse strip 82 of these flattened portions already in this condition of the package but in most cases it is preferred to first foldthe regions to be kl'ieat-sealed vertically upwards as this is shown in Fig, A10 whereby the regions to be heat sealed are more 'accessible to a conventional heat sealing device. This application of heat and pressure will provide a hermetic seal which in the absence of intervening or doubled up layers is completely free from the danger of leakage. f

After the top closure seam has been formed, it may be folded flat and the resulting tabs 83 and 84 may be folded into the body of the package, as this appears in Fig. 11. The top closure flaps may now be folded into closing position in a number of different ways for example by first folding end panel aps 59 and 60 into position (Fig. 12) and then folding main panel flap- 55 and finally main panel flap 55 into closing position. Tab or ear 66 attached to flap 56 may be adhesively secured to end panel 53, as shown in Fig. 13, although, of course, it is also possible to fold this tab inwardly so that it doesnt appear in the iinished package.

It will be noted that the present invention provides a simple, inexpensive and highly effective method for converting sheet material having a fusible inner surface into a hermetically sealed package having a combination of seams formed by adhesion and of seams formed by heat fusion. The invention teaches the art, the forming of a four-sided tubular carton having a four-sided tubular liner incorporated therein by a few and simple folding operations without requiring any complicated and expensive special machinery. Moreover, the invention also discloses a novel type of four-sided packaging medium involving an outer carton and an inner liner which is formed with a minimum amount of material and which has various desirable properties, such as the absence of intervening and doubled up layers in any one of the seams.

Although the present invention has been described in connection with a few preferred embodiments thereof, variations and modifications may be resorted to by those skilled in the art without departing from the principles of the present invention. Thus, while in the four-sided tubular carton it is preferred to provide the longitudinal seam of the liner by means of an adhesive, in some cases heat sealing may be resorted to without materially changing the finished structure. I consider all of these variations and modifications to be within the true spirit and scope of the present invention as disclosed in the 6 foregoing description and defined by the appended claims.

Iclaim:

1. The method of forming a lined tubular packaging medium which comprises attaching a liner sheet to a carton' blank having at least four parallel score lines defining pairs of main and end panels and a glue flap so as to leave the liner sheet unattached to the several panels at the marginal edges thereof, folding said carton blank and liner along one of said score lines, folding back one of the longitudinal marginal strips of said liner about the free edge of said glue flap, folding said carton blank and liner along another one of said score lines to bring the longitudinal marginal strips of the liner into a cooperating position and one end pane1 in contact with the said glue flap, and then independently securing said liner and said carton ends together to form a concentrical tubular carton and separate liner structure.

2. The method of forming a lined tubular packaging medium in collapsed form adapted to be erected before lling which comprises attaching a liner sheet to a carton blank cut and scored along four parallel score lines to denne pairs of main and end panels with top and bottom closure flaps and a glue iiap so as to leave the liner sheet unattached to the several panels at the marginal edges thereof, said liner sheet having substantially the same dimensions as said carton blank and having one of its longitudinal edges protruding beyond the corresponding edge of the carton blank, folding said blank and thereby simultaneously folding said liner along one of said score lines, folding back said protruding portion of the liner about the free edge of the glue flap, simultaneously folding said carton blank and liner along another one of said score lines to bring the folded-back portion of the liner into contact with the other longitudinal edge thereof and at the same time to bring said glue ap into contact with a panel of said blank, and then adhesively securing the contacting portions of the carton and of the liner together independently from each other to form a tubular carton with a separate tubular liner therein.

3. The method of forming a lined tubular .packaging medium adapted to be erected from collapsed form before filling which comprises attaching a liner sheet fluid-tight and fusible at least on the top surface thereof to a carton blank cut and scored along at least four parallel score lines to denne pairs of main and end panels with top and bottom closure aps and a glue flap in such a position as to have one of the longitudinal edges of the liner protruding beyond said blank so as to leave the liner sheet unattached to the several panels at the marginal edges thereof, said blank having hingedly connected ears adapted to longitudinally extend the edge of said glue ilap to the full length of the blank, folding said blank and thereby simultaneously folding said liner along one of said score lines, folding back said protruding portion of the liner about the folding edge defined by said glue flap and said ears, simultaneously folding said carton blank and liner along another one of said score lines to bring the folded back portion of the liner into contact with the other longitudinal edge thereof and at the same time to bring said glue flap into contact with a panel of said blank, and then adhesively 'securing the contacting portions of the carton and of the liner together independently from each other to form a tubular carton with aseparate tubular liner therein, said carton being adapted to be squared up together with said liner and said liner adapted to be hermetically sealed by applying heat and pressure to a transverse top and bottom region thereof; after said folding ears ofthe carton have been folded `avvay from the liner.

4. The method of forming a lined tubular packaging medium adapted to be erected from collapsed form before lling which comprises attaching a liner sheet fluid-tight and fusible at least on the top surface thereof to a carton blank out and scorped along at least fourrlongitudinal score lines to define pairs of main and end panels with top and bottom closure aps and a glue ap in such a position as to have one .of the longitudinal edges of the liner protruding beyond said blank so as to leave the liner sheet unattached to the several panels at the marginal edges thereof, said glue ap having the same length as said panels and being extended at each end to the full length of said carton blank by means of ears hingedly connected to a top and a bottom nap, folding said blank and thereby simultaneouslyvfolding said liner along one of said score lines, folding back said protruding portion of the liner about the folding edge defined by said glue flap and said ears, simultaneously folding said carton blank and liner alongfanother one of said score lines to bring the folded-back portion of the liner into contact with the other longitudinal edge thereof `and at the, same time to bringy said glue flap into Contact with apanel of said blank, securing the contact-ing fusible faces of the liner edges together with a reactivable fusible adhesive along a strip parallel-spaced from the edge of the glue flap thereby forming a flattened expandable fluid-tight longitudinal seam having its fold line substantially in the medial line of one of said end panels, and then adhesively securing the contacting portions of the carton together, said lined tubular carton being adapted to be erected together With said liner and said tubular liner being adapted to be hermetically sealed by applyingheatv and pressure to flattened top and bottom portions thereof after the closure flaps of the carton have been folded away from the liner and said folding ears have been Withdrawn from the interspaoe between said longitudinal seam and the body of the liner.

HARRY F. WATERS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,905,334 Bicker Apr. 25, 1933 1,947,664 Staude Feb. 20, 1934 2,284,604 Brooks May-26, 1942 2,216,527 Weiss et al Oct. 1, 1940

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