Manufacture of paperboard cartons with liquid-proof liners
United States Patent 11 1 [111 3,878,771 Malcolm 5] Apr. 22, 1975 MANUFACTURE OF PAPERBOARD CARTONS WITH LIQUID-PROOF LINERS James A. Malcolm, l lngleside Dr.. Downsview. Ontario. Canada Filed: June 26, 1972 Appl. No.: 265.964  
 Inventor:  
 References Cited UNITED STATES PATENTS ll/l937 Bergstein 93/36.0l X 2/ i942 Gardner 93/360! 7/1964 Christensson... 93/366 Il/l970 Wood 93/36.0l UX Primary Examiner-Roy Lake Assistant l-lraminer-James F. Coan [57] ABSTRACT the blanks and cover adhesive thereon so that the assembled blanks and liners can if desired be stacked and stored. The liners are made from continuous tubular flexible material that is fed around a rotating cylinder where the liners are severed from the continuous material. The liners are sealed across one end, forming bags which when the containers are set up form ears at corners thereof. An ear can be used as a corner pouring spout; an ear can be adhered to an end flap of the container to be pierced by a pouring spout; and the container can be opened at a corner where the bag is adhered thereto. thereby opening the bag.  
 l4 Claims, 20 Drawing Figures sum u or 6 3878771 PATENTEDAPRZZIHTS MANUFACTURE OF PAPERBOARD CARTONS WITH LIQUID-PROOF LINERS CROSS-REFERENCES TO RELATED APPLICATIONS Nil BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to the manufacture of containers from paperboard carton blanks to which flexible bags are attached to serve as fluid-containing liners from which the contents can conveniently be poured.  
 2. Description of the Prior Art For holding liquids or other fluid materials it has heretofore been proposed to provide containers made of paperboard and lined with a fluid-impermeable material in order to provide an inexpensive, preferably rectangular container that can be easily disposed of, but various difficulties have been encountered in producing, storing and readily setting up such containers into a structure that is strong, full, capable of stacking, easily opened and easily emptied, with materials compatible with the contents of the container.  
 SUMMARY OF THE INVENTION A In accordance with the present invention a flexible bag, of material impermeable to the intended contents, is accurately positioned on a flat carton blank and affixed thereto by adhesive covered by the bag. To form the bag. continuous tubular material is fed to a rotary cylinder where the bag is cut from the material and laid against thecarton blank. Patterns of adhesive ensure that as the carton is set up the bag is opened to substantially fill the carton and be supported thereby, the bag having one end closed by a seal transverse to the bag anddefining a bag corner or car of surplus bag material located adjacent a corner of one&#39;flat end of the carton, the carton being openable at that corner so that the ear can be used to form a pouring spout. An ear of the bag can be affixed to said end of the carton, to be pierced by a pouring spout. Part of the sealed end of the bag can be adhered to a corner of the carton to be opened therewith. The bag is filled from the opposite end, which can be closed by any convenient means.  
 &#39; BRIEF DESCRIPTION OF THE DRAWINGS The making of preferred embodiments of the invention is illustrated in the accompanying drawings in which:  
  FIG. 1 shows diagrammatically apparatus for applying adhesive to paperboard carton blanks, for forming bags from tubular liner material. and for assembling the blanks and bags;  
  FIG. 2 is a longitudinal section through parts of the apparatus of FIG. 1;  
  FIG. 3 shows diagrammatically the folding and gluing of an assembled blank and bag in forming a container therefrom;  
  FIG. 4 shows the carton blank with the tubular bag correctly positioned thereon;  
 FIG. 5 shows one of the stages in folding the blank;  
  FIG. 6 shows the container erected or set up, but with the ends of the carton open;  
  FIG. 7 showsthe container with one end of the carton closed;  
  FIG. 8 shows the other open end of the carton with the bag ready for filling;  
  FIG. 9 shows the same end as in FIG. 8 but with the bag filled and sealed;  
 FIG. 10 shows the container filled and closed;  
  FIG. 1 1 shows how the container can be opened from the end shown closed in FIG. 7;  
  FIG. 12 shows another carton blank with a tubular bag correctly positioned thereon (parts of the bag being cut away for clarity of illustration);  
  FIG. 13 shows a container formed from the blank and bag of FIG. 12, with the ends of the carton open;  
  FIG. 14 shows the container of FIG. 13 during a stage of closing and sealing one end of the carton;  
  FIG. 15 is a longitudinal section through the fully closed end of the container of FIG. 14;  
  FIG. 16 is a longitudinal section similar to FIG. 14 but showing a pouring spout inserted into the container;  
  FIG. 17 shows the container of FIG. 16 with the pouring spout inserted;  
 FIG. 18 shows the pouring spout;  
  FIG. 19 shows another carton blank with a tubular bag positioned thereon (parts of the bag being cut away); and  
  FIG. 20 shows a container formed from the blank and bag of FIG. 19.  
 DESCRIPTION OF THE PREFERRED EMBODIMENTS The carton blank 10 shown in&#39;FIG. 4 consists of a sheet of paperboard (which term as used herein includes corrugated or uncorrugated board) that has been cut and creased in a die (not shown) to define four rectangular side-forming panels 11, 12, 13 and 14, with flaps 11a, 12a, 13a and 14a protruding beyond the ends of the panels for closing what will ultimately be the flat top end of a carton, and flaps 11b, 12b, 13b and 14b protruding beyond the opposite ends of the panels for closing what will ultimately be the flat bottom end of the carton. The flaps 11a and 12a are rectangular and are scored along lines 15, 15&#34; which will ultimately coincide with a diagonal 15 of the upper end of the carton (FIG. 7). The flaps 13a and 14a are approximately triangular, terminating with their hypotenuses along lines 15&#34; and 15&#34; which will also ultimately eoincide with the diagonal 15. Along the crease that separates the flap 11a from panel 11 the blank is weakened by a perforated line 16 that deviates downwardly at 17, adjacent what will be a corner of the carton, to form a tab, and then continues at 18 along the crease that separates the flap 12a from panel 12. The panel 14 has a narrow flap along its free edge, and within the body of each panel 13 and 14 is a flap 19 defined by a straight crease line 19a and a curved perforated line 19b to form a handle, as seen in FIG. 11. (For simplicity the flaps 19 have not been shown in FIGS. 1 and 3.) Applied to the central panels 12 and 13 of the blank 10 is a first widthwise line or pattern of adhesive 20 which extends along what will be the top end of the carton, and another such adhesive line or pattern 21 is applied near the opposite end. The line 20 crosses the juncture of panels 12 and 23 at x which will form one corner of the carton.  
  A flexible liner 30 is laid flat on the blank 10 as shown in FIG. 4, over the adhesive lines 20, 21 to which it adheres. The liner is of material suitable for holding liquids. the material of the liner being chosen so as to be impermeable to the liquid that is to to hold. The liner illustrated may be a transparent polyethylene bag having a transverse seal 31 at one end and open at its other end 32. The bag material is of course chosen to suit the liquid or granular or other fluid material that the bag is to contain. The bag is laid over the central panels 12 and 13 and, when flat, is coterminous with the total width of these adjoining panels, protrudingbeyond the ends of the panels over the flaps 12a, 13a and 12b, 1312 but not beyond the longitudinal extremities of the flaps. As will be seen, the longitudinal distance d between the seal 31 and the adhesive line 20 (coincident with the crease line 18) must be at least half-the length of the diagonal 15, d being equal to the distance between point x, where adhesive line 20 crosses the juncture of panels 12 and 13, and point z spaced longitudinally from x on seal 31. The other end 32 of the bag must protrude beyond the adhesive line 21 sufficiently far to have adequate material to close the end 32 once the bag has been filled. On the flaps 12b, 13b are spots of adhesive 33 which detachably secure the bag to these flaps.  
  Apparatus for producing the knocked down container of FIG. 4 is illustrated in FIG. 1. Carton blanks that have been cut, creased and perforated, ready for gluing, are stacked in a feed tray 34 from which a rotary combing device 35 of conventional type delivers the blanks in succession to a conveyor 36. The blanks pass below a rotary gluer 37 which applies the adhesive lines 20, 21 and spots 33, to each blank, as for example by means of raised elements 21, 33 (FIG. 2) which are supplied with glue from a pot 38 by rollers 39, 40.  
  The blanks travel, adhesive line 20 and adjacent end flaps leading, under a rotating combiner cylinder 41 of a machine 42 which makes the bags and positions them accurately on the blanks. To hold the blank 10 on the conveyor 36 the latter may be perforated and have a vacuum box (not shown) under it. The machine 42 is basically a known machine for laying windows over openings in carton blanks (for example, a Model Triple A window machine made by International Paper Box Machine Company of Nashua, N.H., U.S.A.), but with important modifications described below. From a spool 43 extruded, seamless tubular bag stock 30 passes continuously between driven feed rolls 44, over an idler roll 45 and around a bob roll 46 onto the combiner cylinder 41, the latter being perforate as at 41a, with vacuum applied to the interior of the cylinder through a line 4112 so that the material 30&#39; clings to the combiner cylinder without blousing the cylinder rotates. For simplicity on illustration, the perforations 41a are not shown in FIG. 2.) Electrostatic properties of the tubular material 30 may also help in holding it against the cylinder. Above the combiner cylinder is a cutting and sealing cylinder 47 having rings 48 which retain an elongated knife 49 and electrical heating bar 50 that register on each revolution of the cylinders with a longitudinal anvil 51 on the combiner cylinder. The tubular material 30&#39; is fed lengthwise between the cylinders 41, 47 and the knife 49 severs the tubular stock 30 (thus forming the open end 32 of a bag 30), and, substantially at the same time, the heating bar 50 forms the transverse seal 31 in a straight line adjacent to and just behind the line of severance. As an alternative to. providing the heating bar 50, the tubular material can be provided with spaced apart transverse seals 31 before it is wound on the spool 43, and the knife 49 can sever the bags adjacent these seals. To ensure that successive bags are spaced apart by the same amoount as the successive blanks 10 on conveyor 36, after a bag has been separated from the material 30&#39; by the knife 49 the bob roll 46 is swung to the broken line position 46&#39;, drawing the sealed, free end of the material 30&#39; away from the severed end of the just completed bag 30, this being accomplished by a roller 52 which runs on a cam 53 of cylinder 47, the roller 52 and bob roll 46 being at opposite ends of a rocker 54 that pivots about the axis of idler 45. Successive bag lengths are severed on successive rotations of cylinder 47. The bags travel with their sealed ends leading. The feeding of blanks 10 is coordinated with the spacing between bags formed at the combiner cylinder to bring the bags precisely into the position shown in FIG. 4 as the bags pass under the combiner cylinder and are pressed thereby against the adhesive lines 20, 21 and spots 33 on the blanks 10. It is to be noted that the bags cover the adhesive lines 20, 21 and spots 33, these being the only adhesive areas on the blank, so that no adhesive is transferred to the mechanisms that contact the blank.  
  The machine 42 can assemble a bag 30 and carton blank 10 on each revolution of the cylinder 41. The machine can be wide enough to run two parallel spools of material 30&#39; and to handle two parallel lines of carton blanks, thus doubling its per hour output so that a production of at least 6,000 knocked down units per hour can be achieved. These flat units are devoid of exposed adhesive areas and if desired can be stacked for further processing as needed. Alternatively, the units may continue, as shown diagrammatically in FIG. 3, to be folded for setting up into containers.  
  FIG. 3 illustrates the operations of a straight-line folder-gluer of conventional type. Knocked down containers consisting of carton blanks 10 with bags 30 affixed thereto enter at the right hand end of FIG. 3, and are folded about the crease 123 between panels 12 and 13, to break this crease, the panels 11 and 12 being laid over the panels 13 and 14 and then returned to their original position. Then gluing means, for example rollers 50, apply adhesive to both the upper and lower sides of the edge flap 14c. Thus, a line of adhesive is applied to the upper side of flap 14c. Another spot of glue 59 is applied to end flap 14b by a glue spotter (not shown). As a first step in setting up the container, the panel 14 having the flap is folded over the flat liner 30, as also shown in FIG. 5, so that the adhesive line 60 (on the underside of flap 14c as seen in FIG. 5) adheres to the liner, as does the adhesive spot 59. It is important that the adhesive line 60 terminates at one end at the distance d from the seal 31 (FIG. 5). At the other end the line 60 terminates at 60b, level with the adhesive line 21. With flap 140 in the position shown in FIG. 5, there is exposed adhesive 61 covering the other side of flap 14c. The panel 1 1 is then folded over, as shown at the left hand end of FIG. 3, to lie upon and adhere to the adhesive 61 on edge flap 14c. At this stage, the knocked down containers might be stored for subsequent use, but if they are to be filled immediately they can proceed to a conventional erecting mechanism (not shown) which erects the carton to the rectangular box condition shown in FIG. 6  
  In the set up condition of FIG. 6, the bag seal 31 runs generally diagonally of the box from adjacent the cor-.  
 ner tab 17, and the bag has been stretched taut along a line adjacent the other diagonal of the box. Tautness along line 15 is ensured by the fact that each half of the line 15 (i.e., the distance between each corner x and the midpoint z of seal line 31) represents the distance d of FIGS. 4 and 5, one half being from the seal 31 to the adhesive line adjacent one end of the diagonal, and the other half being from the seal 31 to the adhesive line 60, adjacent the other end of the diagonal 15 of the carton, the adhesive line 60 being on the flap 140 which joins the two sides 11 and 14 of the carton.  
  Although the bag is tautalong the line 15&#34; of FIG. 6, the remainder of the closed end of the bag forms a pair of corners or ears 70 of material that is surplus in the sense that it must be pressed or folded into the carton when the flaps 11a, 12a, 13a and 14a are later closed to the positions shown in FIG. 7 where they form a substantially flat container end. As will later appear, the provision of the generally conical car 70 at the openable corner 17 of the carton is useful in dispensing the contents of the container.  
  The flaps 14a, 12a, 13a and 11a are closed in that sequence, adhesive being applied as they are laid one upon another. Flap 14a, as it is closed, presses downwardly the ear 70 adjacent to it. but because flap 14a terminates along hypotenuse 15&#34;&#34; the other ear 70 is not pushed away by flap 14a but is left in a position to be pressed down by the next flap to be closed, namely, 12a. Referring to FIG. 8, which shows the container of FIG. 7 inverted, it is to be noted that the unsealed end 32 of the bag was pulled open in erecting the container, because the longitudinal adhesive line 60 pulls one side of the bag away from the opposite side which adheres to the lines 20, 21, the complete opening of end 32 being ensured by the spots of glue 33, 59 which hold the bag to the flaps 12b, 13b and 14b adjacent the unsealed end 32 of the bag.  
  The squaring up of the carton requires the sealed end of the bag to draw inwardly towards the open end 32, the bag portions in FIG. 6 between each corner and the bag seal at 1 having moved through ninety degrees from their positions in FIG. 4, and the seal 31 having twisted downwardly at z. to form the cars 70 which extend upwardly at angles of about 45 from z. The fact that end 32 opens fully ensures that air pressures within and outside the bag are equal so that there is no air pressure differential tending to pull the bag out ofplace as the carton is set up. The containers may be stored in the condition shown in FIG. 8, with the bag ends 32 open, or they may be immediately filled with liquid or other flowable material. The open end 32 is then closed and, if necessary, sealed as by a transverse seal 72 as shown in FIG. 9. When the end 32 is closed it is pulled away from the glue spots 33, 59 which were provided to ensure opening of the end 32. The flaps 11b, 12h, 13h and 14b are then folded and glued down (the order is immaterial) to form a second flat closed end for the container, as seen in FIG. 10. Such a container is light in weight, and having flat sides and ends it can be stacked and packed tightly with other such containers. The hypotenuses of the triangular flaps 13a, 14a lie along the diagonal 15 which is coincident with the taut diagonal 15&#34; of the inner bag 30. Because the carton is weakened along the tab 17 at one corner, the container can easily be opened by pressing the tab 17 inwardly and tearing the flaps 11a, 12a along the perforated lines 16 and 18, folding these two flaps back along the&#39;score lines 15&#39; and 15&#34; (FIG. 11), the hypotenuse offlap 13a serving as a fulcrum. One of the ears 70 is thereby exposed, and it can be pulled out and cut open as at 70a to serve as a pouring spout for dispensing the contents of the container. As indicated in FIG. 11, the flaps 19 can be pressed inwardly with the fingers by freeing them along the perforated lines 19b, thereby providing recesses whereby the container can be grasped when pouring its contents from the spout opening 70a. The inwardly swinging-flaps l9 protect the inner bag from being perforated by the finger nails. The adhesive lines 20, 21 and 60 are spaced from the flaps l9 and consequently the bag can flex when the flaps are pressed inwardly. The bag deforms particularly easily adjacent the flap 19 of panel 14 because the adhesive lines 20 and 21 do not extend onto panel 14.  
  The bag fits snugly into the carton 10 because its transverse dimensions are the same as the transverse dimensions of the interior of the carton, and the bag walls are pulled closely against the walls of the carton because the adhesive lines 20 and 21 affix the bag to two sides of the carton and the adhesive line 60 pulls the bag against the other two sides of the carton as the container is erected, the vertical adhesive line 60 on the inturned flap 140 being diagonally opposite the center points of the horizontal adhesive lines 20 and 21. The line 20 could be spaced slightly from the ends of panels l2, 13 if it is desired to reduce the amount by which the spout can protrude from the carton when it is opened, but the distance d must be maintained between the seal 31 and the line 20. The adhesive line 21 is spaced upwardly from the bottom of the carton sufficiently to make room for the end 32 of the bag when it has been closed; a spacing of about half an inch is satisfactory. The end h ofthe adhesive line 60 is similarly spaced upwardly to ensure that no undue tension is applied to the bag material. The bag and the carton can be completely filled, the carton providing physical support for the flexible bag and its contents. The adhesive lines 20, 21 and 60 prevent the bag from collapsing when its contents are poured out, but it would be possible to employ an adhesive which allows the bag to release from its attachments to the carton and thus deflate as it is emptied. (To achieve this one might wish to use a bag material which is slightly pervious to the contents of the bag, and by using an adhesive which loses its effectiveness when exposed to such contents.) The adhesive line 20 extends close to the tabbed corner 17 to affix the bag to the carton adjacent that corner and thus prevent collapse of the pouring spout, though the ear is not itself affixed to the carton. If any difficulty should be encountered in pouring out the contents of the bag, the other ear 70 can be exposed and opened to provide ingress for air or to serve as a second spout.  
  The bag 30 may consist of a laminate of nylon (forming the outside of the bag, and used for its strength and barrier qualities) and polyethylene (used at the inside for its heat sealability). The adhesive used must be compatible with the bag material which it engages. It is not necessary to use an adhesive that remains tacky, the described method making it unnecessary to apply adhesive a substantial time before it is used.  
  Another container made according to the method of the present invention is illustrated in FIGS. 12 to 17. In this embodiment, a flat paperboard blank consists of four rectangular side-forming panels 111, 112, 113,  
  1 14 having rectangular flaps 111a, 112a, 113a, 114a respectively protruding beyond one end and rectangular flaps 111a, 11211. 113b, 1l4b at the other. On the adjoining central panels 112, 113 are a pair of widthwise lines of adhesive, a first 120 extending along the ends from which the flaps 112a, 113a protrude, and a second 121 extending near the opposite ends of the central panels. Spots of adhesive 133 are provided on the flaps 1121), 113b to serve the same purpose as the spots 33 of the first embodiment. All the adhesive so far described is, as in the first embodiment, covered by a liner bag 130 which covers the whole of the inner surfaces of panels 112, 113 and the major part of the end flaps of these panels, the bag 130 having a sealed end 131 and an open end 132. Bags 130 are laid on blanks 110 by the method illustrated in FIG. 1 so that the bags cover all the adhesive that has been applied at the gluer 37, so that the knocked down containers emerging from the machine 42 have no exposed adhesive and can if desired be stacked and stored. The ends of each bag 130 do not protrude beyond the free ends of the end flaps of the carton blank, and thus are protected by the carton blank against fouling.  
  At the juncture of the panels 112, 113 the adhesive line 120 is the distance d from the transverse seal 131 ofthe bag, the distance d as before being half the length of the diagonal of the set-up container. To set the container up, adhesive is applied to both sides of an edge flap 111c of panel 111, a spot of adhesive 159 is applied to flap 114b, panel 111 is folded over panel 112 so that the line of adhesive 160 on edge flap lllc sticks to the bag, the end of line 160 being the distance d from the bag seal 131. Panel 114 is folded over panel 113 and sticks to the other adhesive side of edge flap lllc to connect the sides of the carton together. and when the carton is squared up it appears as in FIG. 13, the bag being taut along the diagonal, as at 115&#34;, between the juncture of sides 112, 113 and the juncture of sides 111, 114. At either end of the transverse bag seal 131 the bag has surplus material forming corners or ears 170.  
  The end flap 113a of the carton blank has, at the end of panel 113, a rectangular portion 300 which is devoid of adhesive and is surrounded by a line of perforations so that portion 300 can without difficulty be removed as described hereinafter. The portion 300 is surrounded by adhesive, namely by the line 120 on panel 113, by lines 120a along the sides of portion 300, and by a line 1201; along the edge of portion 300 remote from panel 113. When the bag 130 is laid on the blank 110 the bag adheres to all these lines of adhesive, and when the carton is set up (FIG. 13) part of one of the ears 170 of the bag is affixed, at the side adjacent flap 113a, around the removable portion 300, without being attached to the removable portion. Where the adhesive lines 120a and 120h meet they have a corner bevel 120(- corresponding to a line that the ear 170 can adhere to without rupture when the carton is set up. This bevel 1200 in FIG. 12 coincides with an imaginary straight line drawn from x, which will constitute a corner of the set-up carton, to the bag apex y. As will be seen, the removable portion 300 has a width (measured along the line 120) corresponding to that of an insertable pouring spout. If this width is so great that it is difficult to achieve a firm bond of the bag to the flap 113a around the entire portion 300, because of the limitation imposed by the bevel lc, it may be necessary to space the bag seal 131 a greater distance than d from the corner .r, thus raising y and increasing the slope of the bevel C to ensure that the bag is firmly held taut across the area of the portion 300.  
  The area 120!) is divided by parallel perforations into fingers 301, best seen in FIG. 14, which abut the portion 300 at their free ends, at the side of portion 300 opposite from line 120 and thus spaced from what will be the edge of the carton at the top of carton side 113. These fingers can be deflected downwardly to facilitate smooth and easy penetration of the container by a pouring spout, as described later.  
  With the carton set up as in FIG. 13, the flaps 112a, 114a, 113a and 111a are folded in, in that order, to close one end of the container. The flap 112a has a rectangular portion 202 removed. ofa size snugly to receive an insertable pouring spout, and also large enough to enable the flap 112a to be closed down at the end of the container without pulling the bag ear 170 away from its adhesion to the lines 120a, 120!) of flap 113a. The flap 114a has a similar cutout portion 204, and the flap 114a is folded down and laid on the upper surface of flap 112a to which adhesive has been applied by conventional means. Flap 113a is then laid down on the upper, adhesive coated surface of flap 114a, and thus overlies the flaps 114a and 112a save where the bag ear 170 is affixed to the flap 113a. On the upper side of flap 113a, as seen in FIG. 14, is a rectangular varnished area 302 which includes and is slightly larger than the fingers 301, and adhesive applied to attach the flap 111a to flap 113a is effective at all areas except 302. Thus, a lifting tab 400 on the flap 111a is adhered to the portion 300 of flap 113a but not to the fingers 301, the tab 400 overlying both the portion 300 and the fingers 301. With the flaps folded down the upper end of the container is as illustrated in FIG. 15, the bag car 170 being located in the cut-away areas 202, 204 of flaps 112a. 114a, and this ear being held taut under the removable portion 300 by the adhesive which surrounds the latter in the areas 120a, 120!) of flap 113a and along the line 120 of side wall 113. The bag can be filled from the other, open end 132 (the opening of this end having been facilitated by glue spots 133, 159), the bag material having been chosen to hold without leakage the desired contents, for example, motor oil. The end 132 is sealed after filling, and the flaps 111b, 112b, 113k and 114!) are closed and adhered together to complete the container.  
  The container can be opened in a manner similar to the one illustrated in FIG. 11, by opening the corner of the container at the juncture of walls 111, 112, thus exposing the bag ear that is not attached to flap 113a, and for this purpose a lifting tab can be provided similar to the tab 17 of FIG. 11. The exposed bag ear can then be cut open. However the preferred mode of opening the container of FIG. 15 is shown in FIGS. 16 and 17, using a metal pouring spout shown in FIG. 18. This spout 500 is the same as a conventional oil can spout except that instead of having a curved guide to fit a cylindrical can it has a rectangular guide 501 that matches the configuration of the container and fits snugly thereover as seen in FIG. 17. The spout has a curved pouring neck 502 that extends through the guide 501 and merges with a bayonet having a curved, piercing tip 502 from which a pair of flanges 503 diverge upwardly, the flanges having openings 504 therethrough. (The distance between the flanges 503 at the guide 501 equals the diameter of the neck 502 at the guide and is herein referred to as the width of the pouring spout.) The first step in opening the container is to lift the tab portion 400, thus lifting the removable portion 300 attached thereto. It will be noted from FIG. 12 that the portion 300 extends slightly into panel 113 so that when the carton is set up its extension forms a small protruding lip 300a (FIG. 15) beneath which one can insert ones fingernail to lift portions 300 and 400. With these lifted, the ear 170 is exposed, stretched taut over the opening left by the portion 300, where ear 170 is easily pierced by the tip 502 of the bayonet. The fingers 301 are also exposed, since the varnish on them prevented them from being attached to, and thus lifted with. the tab 400, and as the spout is pushed downwardly the fingers 301 are depressed by the flanges 503 into the container, the flanges engaging first the middle fingers and then the outer ones. These easily flexed fingers cause little resistance to the downward progress of the spout, so that only slight pressure is required to press the spout to the fully inserted position shown in FIGS. 16 and 17. Because the spout is so easily inserted, it is not necessary to grasp and squeeze the container as the spout is pressed down. To squeeze the container would of course tend to force its contents upwardly as the spout is inserted, causing spillage. The guide 501 assists in positioning the spout on the container and ensures that when the container is inverted its contents all flow out the neck 502. The wall 1 13 may be provided with a line of weakness 113c to enable the wall to bulge easily behind the bayonet, and the glue line 120 may be extended downwardly in this region, as at 113d (FIG. 12) to ensure that the bag 130 is not&#39;dislodged from the carton wall and to reinforce the bag against leakage.  
  The cross-sectional size of the pouring spout (ignoring the guide 501) approximates the cutout portions 202 and 204 of the flaps 112a, 114a, and the combined area of the removable portion 300 and the fingers 301, so that the spout fits snugly into the container.  
  In the containers described above. the bag is attached to the carton at and adjacent to the points x of FIGS. 4 and 12, and thus at a corner in which no ear 70 or 170 of the bag is nested when the container is set up. The attachment of the bag to this corner of the carton can be used for an alternative mode of opening the container, as can be most easily described by reference to the embodiment illustrated in FIGS. 19 and 20. In this embodiment a carton blank 610 consists of rectangular panaels 611, 612, 613, 614 having flaps 611a, 612a, 613a. 614a at one end and flaps 611b, 612b, 613b, 6141) at the other. A line of adhesive 620 is applied on the panels 612, 613 along the crease line separating these panels from their flaps 612a, 613a, the line 620 being extended downwardly as at 620d at the juncture of the panels 612 and 613. Another adhesive line 621 crosses panels 612 and 613 near their other end. Spots of adhesive 633 are applied to flaps 612b, 613b, and a bag 630 is formed and laid over the central panels 612, 613 and parts of their end flaps by the apparatus of FIG. 1, the bag having a sealed end 631 and an open end 632. As before, the sealed end 631 is located the distance d from point x at the juncture of panels 612, 613. Both panels 611 and 614 are provided with edge flaps 61 1c and 614c respectively. When the carton is to be set up, the side of flap 614a seen in FIG. 19 is covered with adhesive, a spot of adhesive 659 is applied to end flap 611b, and both sides of edge flap 6110 are coated with adhesive, but the adhesive on the side of flap 6110 seen in FIG. 19 terminates at 611d level with the lower edge of adhesive line 621. Panel 611 is folded over panel 612 so that flap 611C and spot 659 adhere to the bag 630, and then panel 614 is folded over panel 613 to adhere to flap 1110. and flap 6140 also adheres to panel 611 and overlies it as seen in FIG. 20 which shows the erected container. The end flaps 611a. 613a, 614a. and 612a are folded down and glued together in that order, the bag 630 is filled from its open end 632, and then the bag is pulled away from the spots 633, 659 and closed, and the end flaps 611b, 612b, 6131), 614b are closed and glued together.  
  In the set-up container the bag is taut along a diagonal of the upper end of the container extending from the corner x to the upper end of the flap 6110, the adhesive at the ends of this diagonal being spaced from the bag seal 631 by the distance d. The line of adhesive 620 secures the bag to the carton along the upper edges of the panels 612 and 613, and adjacent corner x these panels are weakened by a perforated line that extends at 616 for a short distance along the crease between panel 612 and flap 612a, then deviates downwardly as at 617 to form a tab portion at the juncture of panels 612, 613, and then extends at 618 for a short distance along the crease between panel 613 and flap 613a. From the outer ends of perforated lines 616 and 618 two crease lines 615 define triangular corner portions of the end flaps 612a, 613a, corresponding in size to triangular corner positions that are removed from end flaps 611a and 614a along lines 615&#39;. When the container is set up. the lines 615, 615 coincide and form a fulcrum about which the corner of the container can be opened by pushing in the tab portion above line 617 and lifting the tab portion and the triangular corner portions of flaps 612a, 613a. It is to be noted that the bag is adhered to the carton both above and below the line 617, and when the tab portion is pushed in and lifted the part of the bag attached to it tears along the lines 616, 617, 618, so that the contents of the container can be poured over the lip formed at the juncture of panels 612 and 613. The additionaladhesive area 620d is provided to ensure that the bag remains affixed to the carton below the pouringlip, to prevent bleeding or leakage of the contents of the bag and consequent weakening of the paperboard. To facilitate grasping the container for pouring, flaps 619 can be pressed inwardly in the panels 611 and 614 about crease lines 619a, the flaps 619 beingdefined by these crease lines and by perforated lines 61%. The carton can be grippedin one hand by pressing one flap 619 inwardly with the fingers and the other flap 619 with the thumb, the flaps guarding the bag against puncture by the fingernails. The edge flaps 6110 and 6140 reinforce the carton along the edge where it is gripped, opposite the corner x.  
  Modifications of the preferred embodiments herein described will readily occur tothose skilled in the art. and are intended to be covered by the subjoined claims.  
 What I claim as my invention is:  
  1. A method of making knocked down containers from flat paperboard blanks each having four rectangular panels for forming sides of a carton, an edge flap on one of the panels for connecting sides of the carton, and end flaps protruding beyond the ends of the panels for closing the ends of such carton, comprising applying adhesive to successive blanks across a pair of adjoining panels, feeding the blanks successively past a rotating cylinder with end flaps of the blanks leading, feeding continuous tubular flexible bag material lengthwise to the rotating cylinder, providing sealed lines transversely of the tubular material at spaced apart intervals therealong, transversely severing the tubular material on the cylinder adjacent to but not coincident with said sealed lines to form successive separate bags each having an open end and one of said transverse sealed lines at the other end, delivering the successive bags around the cylinder and applying them by the cylinder flat against the adhesive on the successive blanks as the blanks pass the cylinder to secure the bags to the blanks, and coordinating the delivery of the bags to the blanks to ensure that each bag covers said pair of adjoining panels of a blank and covers and adheres to said adhesive and protrudes beyond the ends of said adjoining panels with the transverse sealed line of the bag spaced from the ends of said adjoining panels by a distance that is at least one half the length of a diagonal of one end of such carton.  
  2. A method as claimed in claim 1, wherein the sealed lines are provided transversely of the tubular material by pressing an elongated heating element against the tubular material on the rotating cylinder to heat seal the material transversely, and wherein the tubular material is transversely severed on the cylinder, at substantially the same time as each transverse sealed line is formed, by pressing against the tubular material an elongated knife adjacent said heating element.  
  3. A method as claimed in claim 1, wherein said pair of panels are central panels of the paperboard blank, adhesive is applied to two sides of said edge flap, and the carton is formed by folding the panel having the edge flap to lay one of said adhesive sides of the edge flap against the flat bag to adhere thereto, and then folding the remaining panel to lie over the other adhesive side of the edge flap to adhere thereto, the adhesive on said one side of the edge flap being spaced from said transverse sealed line of the flat bag by a distance at least one half the length of a diagonal of one end of such carton.  
  4. A method as claimed in claim 3, wherein the adhesive applied across said pair of central panels comprises apair of transverse adhesive patterns adjacent the ends of said central panels.  
  5. A method as claimed in claim 3, wherein adhesive is applied to end flaps of the blanks to adhere to the bags and facilitate opening the bags when the carton is set up. i  
 6. A method as claimed in claim 1, wherein an end flap, that adjoins one of said pair of panels is provided witha removable portion at an end of said one panel, adhesive is applied to surround said removable portion, and the bags are laid on the blanks to cover and adhere to the last mentioned adhesive.  
 7. A method as claimed in claim l, wherein the cylinder is perforated and holds the bag material against it by vacuumlapplied to its interior.  
  8. A method of making containers from flat paperboard blanks each having four rectangular panels for forming sides of a carton, an edge flap on one of the panels adjacent the ends of said adjoining panels, and  
 feeding the blanks successively past a rotating cylinder which applies flat against each blank a flexible tubular bag that adheres to and covers said adhesive patterns and is coterminous with the total width of said adjoining panels, the bag being laid to protrude beyond the ends of said adjoining panels with an end seal of the bag longitudinally spaced from one of the transverse adhesive patterns, at the juncture of said adjoining panels, by a distance at least one half the length of a diagonal of one end of such carton, adhesive being applied to two sides of said edge flap, and such carton being formed by folding the panel having the edge flap to lay one of said adhesive sides of the edge flap against the flat bag to adhere thereto, and folding the remaining panel to lie over the other adhesive side of the edge flap to adhere thereto, the adhesive on said one side of the edge flap being spaced from said seal of the bag by a distance at least one half the length of a diagonal of one end of such carton.  
  9. A method as claimed in claim 8, wherein successive bags are formed by feeding extruded tubular bag material to said cylinder where bags are cut from the tubular material and the end seal of each bag is formed in a straight line across the width of the leading end of the bag.  
  10. A method as claimed in claim 9, wherein said cylinder is a vacuum cylinder for holding the bags thereagainst to apply them to the blanks.  
  11. A method as claimed in claim 8, wherein the adhesive is applied to the edge flap and the panels are folded in a straight-line folder-gluer.  
  12. Amethod as claimed in claim 11, wherein spots of adhesive are provided on end flaps of the blank to adhere to the bag adjacent its unsealed end and thereby open said unsealed end when the carton is set up.  
  13. A method of making knocked down containers from flat paperboard blanks each having four rectangular panels for forming sides of a carton, an edge flap on one of the panels for connecting sides of such carton, andend flaps protruding beyond the ends of the panels for closing the ends of such carton, comprising applying to successive blanks a pair of transverse patterns of adhesive extending across the widths of a pair of adjoining panels adjacent the ends of the panels, and feeding the blanks successively past a rotating cylinder which applies flat against each blank a flexible tubular bag that adheres to and covers said transverse adhesive patterns and is coterminous with the total width of said pair of panels, the bag being laid to protrude beyond the ends of said pair of panels with an end seal of the bag longitudinally spaced from one of the adhesive patterns, where it crosses the juncture of said pair of panels, by a distance at least one half the length of a diagonal of one end of such carton, the flat blank and bag being devoid of exposed adhesive whereby they can be stacked with other such flat assembled blanks and bags without adhering&#39;thereto, an end flap being provided with a removable portion adjoining one of said pair of panels and defined by a line of weakness and surrounded by adhesive which is covered by and adheres to the bag, the removable portion being unattached to the bag.  
  14. A method of making knocked down containers from flat paperboard blanks each having four rectangular panels for forming sides of a carton, an edge flap on one of the panels for connecting sides of such carton,  
 that is coterminous with the total width of said pair of panels and protrudes beyond the ends of said pairs of panels and adheres to and covers the adhesivc, with a transverse end seal of the bag longitudinally spaced from said transversely extending adhesive by a distance at least one half the length of a diagonal of one end of such carton.