US2252106A

US2252106A - Packaging method

Info

Publication number: US2252106A
Application number: US359823A
Authority: US
Inventors: Harry F Waters
Original assignee: Individual
Current assignee: Individual
Priority date: 1940-10-05
Filing date: 1940-10-05
Publication date: 1941-08-12
Anticipated expiration: 1958-08-12

Description

Aug. 12, 1941. H. F. WATERS PACKAGING METHOD 4 Shehets-Sheet 1 Filed ot. 5, 1940 IYNVENTOR. HHHVFWHTERLS- HTTRNE'Y All@ 12, 1941 H. F. WATERS 2,252,106

PACKAGING METHOD Filed oct. 5, 1940 4-sneetssheet 2 INVENTOR. BY HH/FTy/r-WHTEFJ HTTR/VEY Aug. 12, 1941. H. F. WATERS PACKAGING METHOD 4 Sheets-Sheet 3 Filed 0G11. 5, 1940 ug.- 12, 1941. H, F WATERS 2,252,106

PACKAGING METHOD Filed 001;. 5, 1940 4 SheetS-Shee'l'l 4 HTTOR/YEY Patented Aug. 12, 1941 UNITED STATES Pa'rl-:lv'lfl OFFICE 2,252,103 PACKAGING Marnon nam F. waters. New York, N. Y. Application october s, 1940, sei-'n1 No. 359.823

14 Claims.

The present invention relates to the art of packaging, and more particularly, to a novel method of forming fluid-tight containers and of packaging commodities therein.

The productwith which the present invention is primarily concerned is ay container of generally moisture-proof and fluid-tight character comprising an outer carton having at least. some flexibility and strength and an inner bag or liner` iiuid-tight and heat fusible at least on y the inner face thereof. I have found that in containers of the described character it is desirable to provide a ybag which is bigger than the inner space of the carton so that in the filled and sealed condition of the bag it will be 15 supported by the carton throughout the entire surface thereof. In other words, the liner may be of a relatively weak material provided it has Vgood fluid-tight qualities since the stresses occurring during transportation and storage are taken up by the outer carton. Containers of the described character have obtained great importance in the packaging art and are' disclosed,l

involved attaching a flat liner sheet to the' carton blank and simultaneously forming a tubular carton structure and a tubular or envelope-like liner structure Within this carton. In both of these instances the container was 1 formed in its flat or collapsed condition and was subsequently erected prior to filling. Various problems were encountered in forming uidtight containers by means of these methods particularly when it was desired tol use a foursided carton. As those skilled in the art know, 5 Fig 2 depicts a longitudinal4 Sectional View it is diilicult, if not impossible, to directly and adhesively secure a collapsed envelope or bag to a collapsed four-sided tubular carton due to the fact that upon erection a container of this type develops substantial stresses in the bottom seam thereof. This can be avoided only by leaving the liner open at both ends which are sealed only after the container vhas been erected. This, of course, involves performing bag making op- (ci. azi-a) tent complicates the use of this type of container.

Itis an object of the present invention to provide a packaging method which completely eliminates these disadvantages and inconveniences of prior procedures.

It is another object of the present invention to provide a continuous method of packaging which starts out from a heat-fusible and Huid- 10 tight liner material and forms or erects such I material about a mandrel. It is a further object of the present invention to provide a novel and improved method of forming nuid-tight, duplex containers involving heat sealing la. Huid-tight sheet material on a mandrel and thereafter combining such erected @and iiuid-tight bag with a carton either by "pushing the erected bag into an erected carton or by wrapping the carton blank around the erected bag while it is still on the mandrel.

It is also within the contemplation of the invention to provide a method offorming fluidtight and hermetically sealed packages which operates in a direct and continuous manner starting from the sheet-like liner material and from the flat carton blankand converts such materials into a nished and hermetically sealed -iiuid-tight package.

Still another object of the present invention is to provide an apparatus for carrying the method of the invention into practice.

The invention also contemplates a packaging method which is simple in character and which may be employed on a practical and industrial scale for the quantity production of Huid-tight and hermetically sealed, packages.

Other and further objects and advantages' of the present invention will become apparent from the following description taken in conjunction with the accompanying drawings invwhich:

Fig. 1 illustrates a top elevational view of a liner or bag integrallyy formed from a single sheet of material; Y

taken on line 2-2 of Fig. 1;

Fig. 3 shows a perspective view of a mandrel having a fluid-tight liner material wrapped around it and sealed along its longitudinal edges;

Fig. 4 is a horizontal sectional view, somewhat fragmentary in character, and taken on line 4--4 of Fig. 3;

Fig. 5 illustrates a perspective view, having parts broken away for reasons of'clarity, and

erations at the filling station and to some exlshowing the longitudinal seams or fins of the liner material flattened into the plane of two panels or walls thereof;

Fig. 6 depicts a plan view of a carton blank on a somewhat reduced scale adapted to be combined with the erected bag appearing in Fig.

Fig. 7 shows a perspective view of the liner supported by a mandrel after it has been combined with a. carton;

Fig. 8 is a similar view of the finished and lined carton in its erected condition during the filling operation;

Fig. 9 illustrates a perspective view of the top portions of the filled container with the mouth portions of the bag flattened into the plane dened by the upper hinge lines of the carton; y

Fig. 10 is a similar view of the top part of the container in the position in which the collapsed mouth portions of the liner bag are hermetically sealed;

Fig. 11 is a similar view of the finished lled and sealed package, the top flaps of the carton being open for clarity of illustration;

Fig. 12 illustrates a top elevational view of a modified bag adapted to be used in the method of the invention;

Fig. 13 depicts a transverse sectional view taken on line I3--I3 of Fig. 12;

Fig. 14 shows the bag illustrated in Figs. 12 and 13 erected on a mandrel;

Fig. 15 is a top elevational view of a six-sided carton blank adapted to be combined with the erected bag;

Fig. 16 is a perspective view of the erected bag combined with the carton;

Fig. 17 represents the carton and bag removed from the mandrel upon which they were formed and in a collapsed condition in which they may be stored and shipped prior to use;

Fig. 18 is a perspective view of the carton and bag in its erected form during the filling operation;

Fig. 19 is a perspective View illustrating an alternative procedure for forming the heat fusible, fluid-tight liner on a mandrel;

Fig. 2O is a similar view showing the liner sheet on a mandrel sealed along its longitudinal edges;

Fig. 21 is a similar perspective view showing the formation of the transverse or bottom edge of the liner on the mandrel; and

Fig. 22 is a similar view of the liner after it has been converted into an erected heat sealed bag ready for insertion into a carton.

Generally speaking, the containers contemplated by my invention have to satisfy certain important considerations. First of all, it is of great importance that in the erected and filled condition of the package, the inner fluid-tight bag should be greater than the inner space of the carton so that the relatively weak material of the bag is supported by the carton walls throughout the entire surface thereof. Another important condition of providing a completely uid-tight and leakage-proof container is that the inner bag should be formed as far as possible exclusively by means of completely fiat seams so that in the sealed regions not more than two layers of material are placed in a face to face position. Experience has demonstrated that in the event that reentrant folds, intervening layers of materials and similar regions are present in which there are more than two layers of the liner material included, such regions will be greatlysubject to the danger of leakage due to the non-uniform thickness of the liner materials therein.-

In accordance with my invention, I first provide a liner or envelope preferably formed of a single sheet of material which is fluid-tight and fusible at least on one face thereof. Preferred examples of these fusible or thermoplastic materials are a sheeted rubber hydrochloride product known by the name Pliofllm, synthetic resinous materials sold under the name Koroseal, Vinylite, and the like. These sheets may be employed in the form of a self-sustaining film or layer or in the form of a layer coated on or laminated to a sheet of flexible material, such as paper. The latter procedure has the advantage that the liner material may be made fusible on one face and is non-fusible on the other so that heat and pressure may be applied to the fusible portion through the unfusible portion whereby adherence of the material to the heat-sealing members is prevented. A bag or envelope may be formed in fiat form by means of folding a sheet of such laminated material about a medial line and heat sealing the resulting structure at least at two lateral edges thereof whereby an envelope closed at three sides and open at one side is obtained. As an alternative, the bag may be heatsealed on a mandrel by means of folding a piece or strip of such liner material, fluid-tight and fusible on at least one face thereof, around the mandrel and applying heat and pressure along a predetermined region. In either case the result is a liner bag or envelope in erected form upon a mandrel and having a continuous coating of fluid-tight material throughout the entire inner surface thereof. This erected bag which is closed at the bottom and is open at the top may now be pushed into an erected tubular carton, or a carton blank of suitable character and of appropriate dimensions may be wrapped around the bag and may be adhesively secured thereto while the bag is still on the mandrel. After the mandrel is withdrawn, a squared-up carton having a squared-up liner therein is provided and may be filled with a commodity in any conventional manner. 'After filling, the mouth portions of the liner or bag are collapsed and are hermetically sealed preferably by the application of heat and pressure along a transverse strip. Hereafter, the resulting tabs of the liner or bag may be folded into the inner space of the carton and the flaps may be closed thereabout.

Referring now more particularly to the drawings, Figs. 1 and 2 illustrate a bag or envelope of the so-called seamless bottom type employed in the method of the present invention. It will be noted that this bag essentially comprises a sheet or strip l of flexible material fusible at least on the inner face thereof. This sheet is folded about a transverse medial line 2 to bring its edges into registering position. 'Ihe resulting structure may be sealed by the application of heat and pressure to two lateral marginal strips 3 thereof, whereby an envelope closed at the sides -and at the bottom is obtained. This bag may now be erected or squared-up on a mandrel 4 whereby the structure illustrated in Fig. 5 is obtained. The heat sealed regions 3 are nattened in the plane of the two side walls of the mandrel and in the same direction whereby they are converted into longitudinal fins 5. Tabs 6 will be provided at the end of the side walls of the erected bag and may be subsequently folded inwards into the plane of the bottom wall of the bag.

Instead of forming the bag in a at or collapsed form and subsequently squaring it up on a mandrel, it is also possible to wrap or fold a sheet or strip of the liner material around a mandrel of suitable shape and then heat seal the marginal-regions of such strip. In fact. in some cases this type of operation is to be preferred since in thiscase the bag is directly formed in an erected shape and the intermediate step of erecting a fiat bag may be dispensed with. It was already suggested to heat seal a suitable sheet or stripon a mandrel or former and thereby to convert it into an erected bag. 'I'hese prior procedures, however, were incapable of providing a bag which was potentially greaterin all of its dimensions than the inner space of the carton into which it was inserted. The reason for this difllcultywas obvious. In order to form the sheet of the bag on a mandrel it hadto be tightly wrapped around the mandrel and since the dimensions of the mandrel had to be necessarily smaller than the dimensions of the carton into which mandrel and bag were subsequently inserted, the bag was necessarily at least slightly smaller than the inner space defined by the erected carton. Thus,- after thebag was lled with a owable or fluid commodity, the inner pressure on the inner walls of the bag was unable to obtain support from the walls of the carton. inner linerremained unsupported by the outer carton, causing frequent rupturing or tearing of the bag and loss of the contents during transportation and storage. As a result of this great difficulty, as far as I know, this procedure was never employed commercially. I have now discovered that this difficulty may be eliminated in an extremely simple manner by means of heat As a result at least a portion of the character ls in Fig. s. Thus, after the seanng operation is completed,- the sealing members are withdrawn, and the resulting fins 5 are flattened into the plane of' end panels 9 and I0, there will 'sion joint-like effect is obtained. In other words,

afterv the bag is inserted into a carton of appropriate dimensions and is filled with a uid material, the bag is capable of slight expansion under the pressure of the contents, this expansion not exerting any appreciable pressure on the material but being taken up by the said slip or expansion joint. This expansion continues until Y the inner filled bag is completely supported by the outer carton throughout the entire surface thereof. l

Whether the bag is first formed :dat and then erected on a mandrel or it is directly made in erected form on a mandrel, the structure illustrated in Fig. 5 is obtained. In order to obtain a completely satisfactory reinforced fluid-tight package, it is necessary' to combine the erected bag with a carton. 'This may be accomplished in various ways. Thus, in the simplest case an erected carton of suitafble dimensions may be formed and the bag may be pushed into the carton while it is still on the mandrel. After withdrawal of the mandreL-the package is ready for Vfilling. Another possibility is to provide a carton sealing the liner material on a mandrel in such a way that the heat sealed region is at a substantial distance from the mandrel surface. I have found that when the resulting seam is flattened into the plane of one of the walls of the erected bag, a structure is obtained which is capable of relative displacement and of an increase in size until the bag is fully supported by the carton walls. This seam structure which operates in the. manner of an expansion joint orl slip joint will be best understood from the con-4 templation of Figs. 3 and 4,

As it win be observed in Fig. 3, sheet 1, which` permanently secured to each other by applying heat and pressure along a longitudinal marginal strip thereof. This is preferably accomplished by means of heat sealing members II and I2 extending in longitudinal direction parallel with the end vpanels of mandrel 4 and of the bag.V

Preferably, one of these heat sealing members I2 is heated by means of an electric resistance.

or heating element (not shown) to a temperature at which the coating or laminating material of theliner is fusible. The other member II is preferably constituted of an at least partially resilient material such as rubber. It will be readily noted that sealing members II and I2 operate along a strip of the bag material which is remote from the end walls of the erected bag on mandrel 4, the distance being denoted byreference blank 23 of the type shown in Fig. 6 having main panels 1a and 8a and end panels 9a and Ina corresponding in dimensions and arrangement to

similar panels

1, 8, 9 and IIl of the erected bag. Main panels 1a andsa are provided with top and bottom flaps I4 and I 5, I6 and Il, respectively,

while similar flaps I8 and I9, 20 and 2l are provided for end panels 9a and Illa. A

conventional glue fiap

2,2 is provided at one end of the carton blank. Iny carrying this modification of my method into practice, carton blank 23 is wrapped around the erected bag and glue flap 22 is secured tothe corresponding portion of end panel 9a. If desired, the carton and the bag may be adhesively secured to each other although in most cases this is not necessary. 'I'he resulting structure will be best observed in Fig. 7 which clearly shows the tubular carton with its top and bottom aps extending in opposite directions and mandrel 4 within the bag.

The next step in my novel packaging method involves closing the bottom flaps of the carton around tabs 6 of the bag which are likewise folded into the inner Space of the carton. 'I'he erected bag may now be filled through a filling device 24 with a predetermined quantity of the commodity to be packaged. Hereafter, the mouth portions of the inner bag extending beyond the main body portion of the carton may be collapsed or brought into a face to face position and may be hermetically sealed by the application of heat and pressure across a transverse strip thereof.

@s it has been pointed out in the foregoing, in order to provide a positively fluid-tight and leakage-proof package, it is desirable to have a structure comprising only completely flat seams. The principles governing this type of seams are disclosed in my copending application Ser. No. 329,254 referred to in the foregoing. I have found that in a carton and bag structure having lateral fins flattened into the plane of one or more panels of the bag, certain conditions have to be satisfied in order to permit the provision of a completely fiat transverse top seam with a minimum of liner material. In order to obtain this result it is necessary to flatten mouth portions of the bag into the plane defined by the hinge lines of the top flaps of the carton and in the direction in which the fins extend. This will be best observed in Fig. 9 in which mouth portions 30 of the bag are shown collapsed against each other and brought into a substantially horizontal position. A fiat top seam may be applied to the mouth portions of the inner bag already in this position. In most cases, however, it is preferred to fold collapsed mouth portions 30 vertically upwards about a line 25 at a distance from center line 26 of the package (Fig. 10). In this position the collapsed mouth portions are readily accessible to a heat sealing device of suitable character and a transverse heat seal or seam 21 may be applied thereto hermetically sealing the inner bag. Thereafter, the resulting

tabs

28 and 29 may be folded in and top flaps I4, I6, I8 and 20 may be closed thereabout and secured in such closed position by means of a suitable quick drying adhesive whereby the fluid-tight package shown in Fig. l1 is obtained satisfying all of the important considerations set forth in the foregoing.

While in the foregoing' a bag of the seamless bottom type has been described, Figs. 12 to 18 illustrate my novel method of packaging applied to a bag having an L-shaped continuous seam incorporated therein. A bag of this type may be made in at form by providing a sheet 3|, fluid-tight and fusible on at least one face thereof, which is folded over about a longitudinal medial line 32 to bring its edges into registering position. L-shaped marginal strip 33 extending along one of the longitudinal edges and one of the transverse edges of this folded structure converts the same into a fiat bag closed at three sides f.

and open at one side.

The first step in this modified packaging method is to erect the bag on a mandrel 34 whereby the structureillustrated in Fig. 14 is obtained. It will be noted that upon erection the bag will have a pair of

main panels

35 and 36 and a pair of

end panels

31 and 38. The L-shaped seam 33 will be converted into a longitudinal fin 39 and a transverse bottom fin 40. In addition, vertically depending tabs 4| and 42 are obtained at the places where the end panels merge with the bottom panel of the erected bag. The erected bag on the mandrel may be combined with a carton of suitable dimensions and having at least the same number of panels, or walls, as the erected bag. 'I'his may be accomplished, for example, by simply pushing the bag, while it is still on the mandrel, into an erected four-sided carton. Another possibility, which is preferred in some cases, involves wrapping a carton of appropriate shape around the erected bag. This carton may be a four-sided carton of the type shown in Fig. 15 having main panels 35a and 36a, end panels 31a and 38a corresponding in dimensions and arrangement to

panels

35, 36, 31 and 38 of the bag. Main panels 35a and 36a are provided with conventional top and

bottom flaps

43 and 44, 45 and 46, respectively, while end panels 31a and 38a are provided with similar top and

bottom flaps

41 and 4B, 49 and 50, respectively. Al conventional glue flap 5I is connected to main panels 36a and is adapted to cooperate with the corresponding portion of end panel 31a to convert the carton into a tubular structure.` Adhesive lines 52 heat sealing device.

are provided on the main and end panels and have the object to secure the bag to the carton. In the event that after combining the carton with the bag the resulting structure is immediately filled and sealed, these adhesive lines may be omitted. On the other hand, if it is proposed to remove the container comprising the carton and the inner bag and to ship it in collapsed form to a filling station, it is necessary to provide medial score lines 53 and 54 in end panels 31a and 38a, respectively. to obtain a six-sided structure. I n this case the duplex container may be co1- lapsed on these medial score lines 53 and 54 and may be shipped and stored in such collapsed form whereby the space requirements are greatly reduced.

'I'he structure obtained after combining the carton with the bag is shown in Fig. 16 illustrating the carton and bag while they are still on mandrel 34. Upon withdrawal of the mandrel, the container may be either collapsed on

medial fold lines

53 and 54, as this is shown in Fig. 1'7, or the bottom flaps of the carton may be closed and the inner bag may be filled with a commodity through a conventional filling device 55. After filling, the mouth portions of the inner bag are collapsed into a fac'e to face position and are hermetically sealed by applying heat and pressure to a transverse marginal strip thereof.

In forming this top closure or seal for the inner bag the same conditions have to be considered as were explained in connection with the previous embodiment of my invention. In other words, in view of the presence of a longitudinal fin 39 in one of the end panels of the bag, the closed top portions of the bag must be first folded into the plane defined by the top hinge lines of 1 the carton and in the direction determined by the fin. Hereafter, heat and pressure may be applied tothe mouth portionsl of the bag across a transverse strip thereof or these flattened mouth portions may be first folded vertically upwards in which position they Aare more accessible to a After the top closure has been made, the resulting tabs of the bag are folded into the carton and the top flaps of the cartonire closed thereabout. I'he procedure followed in making this top closure is practically identical with the manipulations illustrated in Figs. 9 to 11, the only difference being that while in Figs. 9, 10 and 11,

tabs

28 and 29 are of equal length d'ue tothe presence of a lateral iln in both end panels, the tabs resulting in the closure of the bag shown in Fig. 18 are of unequal length since there is only one lateral fin 39 present. Due to the extreme similarity of these procedures, no

detailed description of 'forminga closure for the structure of Fig. 18 is believed necessary.

In the foregoing, I have explained the various steps of my novel packaging method by means of which a preformed fiat bag having an L-shaped seam may be converted into a finished and hermetically sealed package. Instead of forming a bag fiat and then subsequently erecting the same on a mandrel it is also possible to form a bag o! this type formed on the mandrel was pushed into an erected carton, the bag had to be necessarily at least slightly smaller than the inner space of the carton. Upon filling the bag with a nuid commodity, the inner pressure of the contents exerted substantial pressure onthe inner walls of the bag and such substantial pressure was likewise exerted in the sealing region, which is generally the weakest portion of a heat sealed bag. Due to this lack of expansion of the bag and due to the fact that the bag was not fully supportedby the carton throughout the entire spacev thereof. breaking or rupturing of the relatively weak bag was frequent. In contrast to this, I found that by sealing the cooperating edges of the liner or bag material at a substantial distance from the mandrel, a slip-joint or expansion joint effect is obtained, which permits restricted expansion of the bag until it is fully supported by the carton throughout the entire surface thereof, such expansion having no appreciable effect on the sealed regions. In other words, I succeeded in forming a bag on. a mandrel which in actual operation has a considerably greater volumetric content than the volume dened by the mandrel.

Referring now to Fig. 19, the first step in forming the liner material intoa bag is to wind a sheet 56 about a mandrel 34 so that its longitudinal edges are brought into a registering position. VHeat'and pressure may be applied to these 30 registering portions of the liner material by means of a pair of

heat sealing members

51 and 58. Preferably. one of these heat sealing members, for example 51, is constituted of a metal and has an electric heating element (not shown) whereby it maybe maintained at a temperature at which the fusible portion of the liner material becomes plastic.I The other heat sealing member 58 may be constituted of a resilient or yielding material such as rubber, in order to applyva unlform and equalized pressure to the regions to be heat sealed. It will be noted that in Fig. 19

heat sealing members

51 and 58 are located at a substantial distance 59 from the surface of the mandrel in order to obtain the expansion joint effect already explained in the foregoing particularly in connection with Figs. 3 and 4.

After the'liner material has been provided with a longitudinal seam and thus has been converted into a tube preliminary to providing the bottom or transverse seam, the tube is pushed down on the mandrel to a suitable extent in order to free the portions to be heat sealed for displacement towards each other (FigQZO).

Prior to forming the bottom seam, lateral seam 60 is flattened into the plane ofthe end panel of the tube. Thereafter the bottom portions of the tube are collapsed and folded in the direction determined by the flattened iin. The procedure followed is exactly the same in forming this bottom closure as that explained in Figs. 9, 10 and 11 in connection with forming the top closure. That is, rstthe collapsed mouth portions are folded in which position the bag may be combined with the carton in one of the ways explained in connection with Fig. 14 and may be filled and sealed at the top.

It will be noted that my novel packaging method provides important advantages for packaging commodities of various character and is especially advantageous for packaging fluids which have to be hermetically sealed, and commodities desired to be sealed in a vacuou's atmosphere such as coffee. The principal advantage of. my novel method resides in that the packaging materials such as liner sheets and carton blanks may be converted into a finished and hermetically sealed package in a simple, direct and continuous manner.

It is also to be observed that while the various steps of my method have been explained for the sake of simplicity as hand manipulations, obviously, all of the steps are preferably carried out by means of machinery. In fact, practically all yof the steps involved in my method may be carried ,out by some of the conventional packaging machines without requiring any complicated or expensive changes.

Furthermore, thelpackaging method of my invention provides a. finished package which employs all of the important structural elements lwhich I have found indispensable for the provision of a practical and commercial hermetically sealed fluid-tight package. In the packages prepared in accordance with my method, the inner liner is bigger. than the outer carton and after filling and sealing is fully supported by the carton throughout the entire surface thereof. Moreover, all of the sealed regions have only two layers of liner material incorporated therein and reentrant folds,'intervening layers and similar danger points of leakage are completely i avoided. All of the seams, includingnthe seam in the top closure, are flat and if in a package made in accordance with my method the completely sealed bag would be withdrawn and the uid contents removed therefrom, for example Although the' present invention has been described in connection with a few preferred embodiments thereof, variations and Ymodifications may be resorted to by those skilled in the art Without departing from the principles of my invention. Thus, while in the foregoing it was dist closed that the filling operation is performed into a horizontal plane and in the direction in l which the attened lateral n is pointing. Thereafter, the collapsed mouth portions are'folded vertically downward along a line at a substantial distance from the center line of the package and a transverse heat seal is applied by means of a pair of transverse

heat sealing members

60 and 6|, at least one of which is heated to a heat sealing temperature by means of an electric heating element. After this ,bottom seam has been provided the resulting tabs 62 and -63 are folded inwardly providing the structure shown in Fig. 22

- f carton, with equal or similarresults.

after the bag has been combined with the erected carton, it is also possible to i'lll the erected bag with the commodity to be packaged and thereafter to insert the4 filled bag into an erected I consider all of these variations and modifications as Within the true spiritfand'scope of the present inventight on at least the inner surface thereof and having only two layers of flexible sheet material in face to face position including the seams, erecting said envelope on a mandrel, combining said erected envelope with a carton, filling said envelope with contents, bringing the mouth portions of said filled envelope into flattened face to face position, and then sealing said flattened mouth portions thereby to obtain a package completely free from reentrant folds and layers of increased thickness in the sealed regions.

2. The method of fluid-tight packaging which comprises providing a flat envelope formed from fluid-tight flexible material with. sealed regions in the longitudinal marginal portions thereof and having only two layers of said material in face to face position including said .sealed regions, erecting said envelope on a mandrel, converting said sealed regions of the envelope into flattened lateral fins pointing in the same direction, inserting said erected envelope into a carton, filling said envelope with contents, bringing the mouth portions of said filled envelope into flattened face to face position, and then applying a at top seal to said mouth portions thereby to obtain a package completely free from reentrant folds and intervening layers and from similar danger points of leakage.

3. The method of fluid-tight packaging which comprises providing a fiat bag with a continuous fluid-tight and fusible inner surface and parallel sealed regions in two longitudinal marginal portions thereof and having only two layers of flexible material in face to face position including said sealed regions, erecting said bag on a mandrel, flattening said longitudinal sealed regions into unidirectionally extending fins, introducing said bag into a carton, filling said bag with contents, folding the mouth portions of said bag in the direction determined by said fins, bringing said mouth portions into flattened face to face relation, applying a fiat transverse seal to said folded and flattened mouth portions, and then infolding the resulting tabs and closing the carton thereabout thereby to obtain a substantially hermetically sealed package having uniform thickness and number of layers incorporated into its sea 4. The method of fluid-tight packaging which r comprises providing a fiat bag integrally formed of a sheet presenting a continuous fluid-tight and fusible inner surface and having an L- shaped heat sealed region extending along two adjacent marginal strips thereof including only two layers of material in face to face position, erecting said bag on a mandrel, flattening said sealed region into unidirectionally extending longitudinal and transverse fins, slipping said erected bag into Ia carton, filling said bag with contents, folding the mouth portions of said bag into face to face position in the directionj determined by said longitudinal iin, applying heat and pressure along a transverse marginal strip of said folded and flattened mouth portions to hermetically seal said bag with at two-layer seams, and then folding the resulting tabs of the bag into the carton and closing the carton thereabout.

5. The method of fluid-tight packaging which comprises providing a fiat bag integrally formed of a sheet presenting a continuous fiuid-tight and fusible inner surface and having at least one longitudinal seam with two layers of the bag material in face to face position, squaring-up said bag on a mandrel, flattening said longitudinal seam into a fin, introducing said squared-up bag into a carton and withdrawing said mandrel therefrom, filling said bag with contents, horizontally folding the mouth portions of said bag in the direction in which said iin is pointing, folding up the top marginal strip of said mouth portions irito face to face heat-sealing position, applying heat and pressure to said marginal strip to hermetically seal said bag with a two-layer transverse searnwhereby the seam regions of the bag are constituted of only two layers of material in face to face position, and then folding the resulting tabs of the bag into the carton and closing the carton thereabout.

6. The method of fluid-tight packaging which comprises providing a fiat bag integrally formed of a sheet presenting a continuous fluid-tight and fusible inner surface and having at least one longitudinal seam including two layers of the' bag material in faceto face position, squaring-up said bag on a mandrel, attening said longitudinal seam into a fin, wrapping a carton blank around said squared-up bag and adhesively securing together the ends thereof, withdrawing said mandrel from said bag, filling said bag with contents, bringing the mouth portions of said filled bag into flattened face to face position and then hermetically sealing said flattened mouth portions and closing said carton thereabout thereby to obtain a package completely free from Ireentrant folds and layers of increased thickness in the sealed regions.

7. The method of fluid-tight packaging which comprises providing a fiat bag integrally formed of a sheet presenting a continuous fluid-tight and fusible inner surface and having at least one longitudinal seam including two layers of the bag material in face to face position, squaring up said bag on a mandrel, fiattening said longitudinal seam into a iin, wrapping a carton blank having top and bottom closure flaps around saidl the inner surface thereof and having at least' one longitudinal seam including two layers of the bag material in face to face position, erecting said bag on a mandrel, wrapping around and adhesively securing to said erected bag a carton blank having a plurality of panels and top and bottom closure flaps and thereby flattening said longitudinal sealed region into a iin, closing the bottom flaps of said carton, filling said bag with contents, folding down the mouth portions of said bag in the direction determined by said longitudinal fins and into the plane defined by the hinge lines of said top flaps, bringing said mouth portions into flattened face to face -position, applying a hermetic heat seal to said mouth portions, and then closing the top flaps thereabout thereby to obtain a package having only two layers of material in face to face position in all of its seams.

9. The method of fluid-tight packaging which comprises providing a fiat bag having a concarton thereabout thereby to obtain a package tinuous fluid-tight and fusible inner surface and a pair of longitudinal seams including two layers of the bag material disposed in face to face position in two marginal portions thereof, erecting said bag on a mandrel to convert it into a bag having four panels, wrapping around and adhesively securing to said erected bag a carton blank having four panels corresponding to those of said bag and having top and bottom closure iiaps thereby flattening said seams into a pair of longitudinal iins extending in the same direction, closingthe bottom flaps of said carton, lling said bag into' flattened face to face position in the direction in which said fins extend and into the plane dened by the hinge lines of said top flaps, folding up the top marginal portions of said bag into heat-sealing position, applying a hermetic heat seal to said upfolded marginal portions, and then folding the resulting tabs into the carton and closing the flaps thereabout thereby to obtain a package having only two layers of material in face to face position in all of its seams.

19. The method of fluid-tight packaging which comprises providing a flat bag integrally formed of a medially folded sheet presenting a continuous huid-tight and fusible inner surface and having an L-shaped heat-sealed seam extendingv along a longitudinal and a transverse marginal strip thereof and including only two layers of the bag material disposed in face to face position, erecting said bag on a mandrel to convert it into a bag having four panels and a flattened longitudinal and transverse fin, wrapping around andA adhesively securing to said erected bag a carton blank having four panels corresponding to those of said bag and having top and bottom closure flaps, closing the bottom flaps of said carton, filling said bag with contents, folding down the mouth portions of said bag into nattened face to face position in the direction in which said longitudinal n extends and into the plane defined by the hinge lines of said top flaps, folding up the top marginal strip of said bag into heat-sealing position, applying a heatseal to said up-folded marginal portions to forni a transverse top seam forming continuation of said L-shaped seam, and then folding the resulting tabs into the carton and closing the flaps thereabout thereby to obtain a package having a single continuous seam with only two layers of material in face to face position.

11. The method of packaging which comprises providing a flat bag fluid-tight and fusible on at least the inner surface thereof and having at least one longitudinal seam including only two layers of the bag material in face to face position, erecting said bag on a mandrel and flattening said seam into a longitudinal iin, lling said bag with contents, inserting said lled bag into a carton, folding down the mouth portions of said bag into flattened face to face position in the direction in which the longitudinal n is pointing, sealing said flattened mouth portions to form a transverse top seam forming continuation of said longitudinal seam, and then closing Said having a single continuous seam including only two layers of the bag material in face to face position and free from layers of increased thick- DESS.

12. The method of packaging which comprises providing a at bag fluid-tight and fusible on at least the inner surface thereof and having at least one longitudinal seam including only two layers of the bag material in face to face position, erecting said bag on a mandrel and flattening said seam into a longitudinal iln, filling said bag with contents, wrapping a carton blank having top and bottom closure flaps around said filled bag and adhesively securing the ends thereof together, folding down the mouth portions of said bag in thedirection in which the longitudinal iin is pointing to bring said portions into iiattened face to face position, heat-sealing said nattened mouth portions to form a twolayer top seam forming continuation of said longitudinal seam, and thenclosing said carton flaps thereabout thereby to obtain a package having a single continuous seam including only two layers of the bag material in face to face position and free from layers of increased thickness.

13. The method of fluid-tight packaging which comprises providing a collapsed envelope constituted of uuid-tight flexible material having marginal strips thereof adhesively secured together in face to face position to form at least one longitudinal seam, squaring-up said envelope, combining said envelope with a carton, filling said squared-up envelope with the contents, bringing the mouth portions of the envelope into face to face position and into a single plane including the upper terminal portion of the longitudinal seam, and then securing said mouth portions together thereby to obtain a fluid-tight package having a single continuous seam including only two layers of sheet material in face to face position.

14. The method of fluid-tight packaging which comprises providing a collapsed envelope constituted of iiexible material fluid-tight and fusible on at least the inner face thereof and having marginal strips sealed together in face to face position to form at least one longitudinal seam, squaring-up said envelope, combining said envelope with a carton, filling said squared-up envelope with a unitary amount of material to be packaged,A bringing the mouth portions of the envelope into face to face position and into a single plane including the upper terminal portion of the longitudinal seam, applying heat and pressure to said mouth portions to seal the lled envelope with a top closure seam forming direct continuation of said longitudinal seam whereby a fluid-tightly sealed package is obtained having a single continuous sealed region including only two layers of the flexible material in face to face position, and then closing said carton about the package.

HARRY F. WATERS.

DISCLAIMER 2,252,106.Harry F. Waters, New York, N. Y. PACKAGING METHOD. Patent dated August 12, 1941. Disclaimer filed June 22, 1944, by the inventor. Hereby enters this disclaimer to

claims

1, 13, and 14 of said patent.

[Oc'ial Gazette August 1, 1.944.]