US2802613A

US2802613A - Liquid carton and seal therefor

Info

Publication number: US2802613A
Application number: US292538A
Authority: US
Inventors: Boyd Robert Leo
Original assignee: American Can Co
Current assignee: Primerica Inc
Priority date: 1952-06-09
Filing date: 1952-06-09
Publication date: 1957-08-13
Anticipated expiration: 1974-08-13

Description

Aug. 13, 1957 R. BOYD LIQUID CARTON AND SEAL THEREFOR Filed June 9, 1952 IN VEN TOR.

' 2066/21. fiq BY w g 2,802,613 LIQUID CARTON AND SEAL THEREFOR Robert Leo Boyd, La Grange Park, Ill., assignor, by mesne assignments, to American Can Company, New York, N. Y., a corporation of New Jersey Application June 9, 1952, Serial No. 292,538 7 Claims. (Cl. 229-7) This invention is related to those disclosed in the applications of LeRoy Staunton, Serial Nos. 270,575, now abandoned, and 270,576, and Ervin B. Kodat, Serial No. 270,603, now Patent No. 2,754,045 all of which were filed on February 8, 1952, covering paper liquid containers and seals therefor.

The present invention, as in the case of those disclosed in the applications above identified, relates to cartons such as are commonly used for the distribution of milk, and is characterized by a corner pouring opening disposed adjacent the top in the side walls thereof, which opening is sealed until it is desired to open the carton.

The present invention differs from those disclosed in the aforesaid applications in that a seal is provided which is made of one or more relatively thin membranes of cellulose material impregnated With a thermosetting resin, which is sealed by heat and pressure in overlying relation to the pouring opening in such a way as to become permanently afiixed to the contiguous areas of the side walls of the carton.

The present invention shares the idea of having a permanent closure sealed in permanent engagement with the upper edge of the side walls of the carton body, but difiers from the latter in that the pouring opening is sealed by an imperforate and relatively unweakened membrane, or membranes, which must be ruptured by a lifting force applied to the corner of the carton at which the pouring incision is provided. The corner of the top, together with the portion of the side walls afiixed thereto which lie above the pouring opening, are thus forced upwardly as the seal is destroyed.

it is among the objects of the present invention to provide a seal for cartons of the class described in which the pouring incision and an area surrounding the latter on the outside of the carton are protected by an overlying seal, which prevents the lip of the pouring opening from becoming soiled and prevents the ingress of contaminating foreign matter.

It is another object of the invention to provide a seal interiorly of the carton which surrounds the pouring incision in a way effectively to exclude the liquid contents from gaining access thereto, thus to preclude the liquid from entering the cut edges defining the pouring opening, which, in the case of cardboard, is a wicking material capable of inducing liquid to flow through the walls of the carton in directions parallel to the surfaces thereof by capillary action. This is objectionable, since the liquid thus entrained into the walls softens the latter and causes them to weaken structurally, with the possibility of incurring failure of the carton.

The present invention, like those hereinbefore identified, is characterized by a corner pouring carton, the pouring edge of which is free from obstructing rings or dams such a might prevent the complete discharge of the contents of the carton, to the end that residual amounts of the contents usually wasted are saved and used.

It is a further object of the present invention to provide a carton that is completely sealed by permanent ice closures at the top, bottom, and pouring incision, until it is desired to void the contents thereof. An improved method for making such a carton is also contemplated.

Other objects and advantages will become apparent hereinafter when the following description is considered in conjunction with the accompanying drawings, in which- Figures 1 to 4, inclusive, are fragmentary sectional elevations taken through the side wall and adjacent top of a carton embodying this invention, at the pouring incision therein; and V Figures 5 and 6 are isometric views of a carton embodying the present invention as shown in the preceding figures.

In the drawings, the body portion 10 of the carton is formed of cellulose material, such as cardboard, which is laminated to requisite strength, and impregnated with a thermosetting resin that is non-toxic, and impervious to liquid. A bottom member 12 is suitably formed and sealed to the edges of the body portion 10. A top member 14 of material similar to that constituting the body portion 10 is formed with an inverted U-shaped channeled marginal portion 16 which is adapted to be inverted upon the upper edges 18 of the carton body and permanently sealed thereto, preferably by thermosetting resinous adhesive. This last operation is usually undertaken by the persons concerned with filling the carton, such as dairymen, who install the top closures and heat seal them in permanent engagement with the upper edges of the carton body after the milk or other liquid contents have been introduced therein.

The side walls 10 of the carton are incised as at 20 completely through the thickness of the material, so as to span a corner of the carton as best appears in Figures 5 and 6. The pouring incision 20 is located adjacent the top, but sufficiently below the flange 16 thereof so as to be unobstructed by the latter prior to being opened.

Seals of tissue-

like membrane

22 and 24 are applied, which are of a weight corresponding to second-sheet tissues commonly used in making carbons of typewritten texts. These tissues are impregnated with a thermosetting adhesive, which is preferably the same as that with which the carton side walls 10 and

closures

12 and 14 are impregnated. The tissues are of a size to overlie the pouring incision 20 so as to eifectively seal the latter while extending in engagement with the adjacent areas of the carton side walls over a substantially greater area than that defining the length of the incision itself.

As shown in Figures 1 and 2, the

tissues membranes

22 and 24 are sealed inside and outside of the carton so as to extend from a point below the pouring incision 20 in overlying relation to the latter to a point beneath the closure flanges 16.

As shown in Figure 3, only the internal membrane 22 need be applied, while in Figure 4 only the external membrane 20 is contemplated. Each is in sealing relation to the pouring incision 20 in a manner corresponding to that disclosed in the preceding figures.

In manufacturing the carton of the present invention, it is desirable to provide a carton wall 10 that is cut so as to provide a smaller cross-sectional area at the bottom of the carton body than at its top when wrapped or folded, so that the latter may be stacked one within another for shipment prior to filling. The pouring incision 20 is cut completely through the wall blank prior to its formation and is located so as to span a corner of the carton body after it is formed on a mandrel. The body blank is impregnated with resin and the internal tissuelike membrane 22, also impregnated, is applied and sealed in overlying relation to the incision 20. The carton body is then wrapped on a mandrel in such a way that the already applied seal 22 is disposed against the mandrel so as to be inside the carton. The purpose for this is that v 3 the internal seal; when first applied and later wrapped, is subject'only to compression, while if the outer seal 24 were to be applied before wrapping on the mandrel, it would be subjected to such considerable, tension upon wrapping as; mi'ght'cauisel itsfailureig 3 Therefore," it is"desirable,' and 'accor'dancejfwith the practices" of j the present invention; to. applyfthe internal in Figure 4, it is nevertheless to have such'membranes both'inside and outsldeas seal f'with"thefca'rton ibody in its" blank' forrn, and .thereafter "to'w'ra'pfthelatter and ?to seal the 'overlappingedg'es of "the"'carton"body' in the usual" way' by application of." heat and pressure thereto, so as to cause the thermos'etting IesinWitli Whichthe'body' is impregnated to adhere at fthe interfac'efof the oyerlappedpertions and to become cu'redin'this position;

An outer seal 24 of tissue-like material impregnated with a ttrermesezang. plasticas previously described is thefiappliedfin' overlying relationto the incision 20, and the" bottom .tlien prefefably is also applied to the carton body; and b'o'thoflthesefare' sealeddnto position at the same'ftime. The "carton is thedairyor tothe ultimate us'er for filling, after which theftopcl'osur'esMare disposed in overlying relation to the upper edges ofthe cartonbody, including the portions 18and those'areas of'the sealing

tissues

22 and 24 which project beneath the flanges All of these parts are thensealedper'manently' together by heat and pressure.

As appears'in Figure 6, to open a carton sealed in this manner, it is preferably disposed on a steady surface, such as a table, and grasped by the hands so that the fingersconfin'e it and steady it against the table. Then, with thethumbs positionedupon a rim of the top adjacentth'ep'ourin'g opening 20, an upward pressure is exerted so as to cause the sealing'membranes 22 and 24 to rupture to permit the pouring incision 20 'tobe opened by a hinge action along the corner of the top, which carrieswithit'thefpermanently attached rim portion 13 defining the-upper edge. of the carton body that overlies the pouring incision'20'. The carton in open position is shown in Figures 2 "and 6.

In the applications identified in the first paragraph of A this specification, the seals were either of relatively heavy stock weakened by'perforations in one way or another to afford removal, or else were of pressure sensitive adhesive'material which could 'be removed from the pouring incision substantially intact.

Iii-the present case, seals of sufiicient thinness to be frangible'are permanently sealed into position over the pouring'incision and are destroyed along the line of the latterupon application of suitable pressure at the time it is'desir'ed to void'the contents ofthe carton. The seal of the present invention is'stronger than the seals heretofore'contemplated and has the advantage of maintaining the'contents oftlie cartons inviolate until the seals are broken beyond'any' chance of disguising the fact. The seal'bei'ng a permanent one, access to the contents is permitted only, by its destruction, which differs from all known'carton seals on the, commercial market today.

In certain of 'the latter, non-wicking material, such as aluminum'foil, is applied to prevent too firm adherence between the portions of the top and the rim of the carton U body, so that the top may be separated therefrom without becoming unduly mutilated. These proposals are objectionable, in thatthe non-wicking material provides an imperfect seal, which, by its very nature, it is intended to do.

The present invention, however, provides a permanent seal, both where the top and bottom closures join the adjacent rim ofthe carton body and at the pouring incision, so that a completely hermetically sealed container is provided until the seal isbroken'as above described.

Although it is within the purview of the present invention to provide one sealing membrane either within the carton as shown in Figure 3, or outside thereof as shown "then'ready tobe shipped to 0 ,as might accidently. shear the preferred embodiment appears in Figures 1 and 2, for the reasons already set forth herein first above. As so applied, each seal reinforces the other and tends to maintain the continuity of the wall surfaces inside and outside the carton effectively to resist lateral displacement between the cut edges, such anyv one of the seals in. two prematurely."

I claim? 1. A method of making. cartons forcontaining and dispensing liquid and'the lik6,-Wl1l'l1 includes-impregnating a blank of relatively heavycellulose material with a liquid'proof, thermosetting'resin, incising apouring opening in said blank, impregnatingablank of relatively light cellulose material with a thermosetting adhesive havin an aflinity for said resin so as to bond therewith when heated, applying apatchof said latter-blankto-the area immediately surrounding said pouring openingtherein by heat and pressure'to seal said heavy blank to' close 'sai'dopening, winding said heavy blank upon'a formingm'andrel' to form ajtube with said patch inside said tube, and thereafter heat sealing atleast one end closure in said tube.

2. The'method of claiml'furtherincluding applying I a secondpatch" from saidlight blank externally of said' tube after the latter'is wound, and heat sealing said second patch. to the walls offsaidtube surrounding said pouring openingjpe'rmanentlyrto close the same until ruptured. 1

3. A liquid dispensing carton having a polyhedral tubular body, permanently attached toth'e ends ofsaid body. to close the same, alinear pouring incision spanning a cornerof said body andextendi'ngfor a limited'di'stance along contiguous portions'of the included side walls andpenetrating the latter, said incision extending'subs'tantially parallel to the top edges of said tubular body and approximately in the plane of the lower face of said top closure and below the flange thereof, a frangible membrane of thinner material than said body disposed inlclosing relation to said incision for being ruptured when. pressure is applied to said top closure adjacent said incision, said membrane having been treated with a thermosetting adhesive and being permanently secured to the side walls of said body circum acent to said incision to seal the same until ruptured.

4. The invention ofclaim 3, in which the membrane described is applied both internally and externally of the carton body.

5. The inventionof is disposed internally of the carton body.

6; The invention of claim 3, in which said membrane is disposed externally ofsaid carton-body.

7. The invention of claim 3, in which said carton body stock is impregnated with a thermosetting resin to which said adhesive bonds when heated in contact therewith.

References Cited in the file of this patent UNITED STATES PATENTS 1,262,992 Stephano Apr. 16, 1918 1,541,143 Hoile June 9, 1925 1,719,923 Cochran July 9, 1929 2,027,747 Morton Jan. 14, 1936 2,302,083 Wilcox Nov. 17, 1942 2,341,379 Householder et a1. Feb. 8, 1944 2,362,862 Sidebotham Nov. 14, 1944 2,398,405 Brooks Apr. 16, 1946 2,460,820 Hogapian Feb. 8, 1949 2,608,341 Eckman Aug. 26, 1952 FOREIGN PATENTS 426,341 GreatBritain Mar; 29. 1935 Y the patch permanently to flanged countersunk top'a'nd bottom closures.

claim 3, inwhich said membrane