US3195795A

US3195795A - Container

Info

Publication number: US3195795A
Application number: US303960A
Authority: US
Inventors: Isaac L Wilcox
Original assignee: Phillips Petroleum Co
Current assignee: Phillips Petroleum Co
Priority date: 1963-08-20
Filing date: 1963-08-20
Publication date: 1965-07-20
Anticipated expiration: 1982-07-20

Description

1. L. WILCOX v 3,195,795

\ CONTAINER Filed Aug. 20, 1965 July 20, 1965 FIG. 4 FIG. 5

INVENTOR.

ISAAC L. WILCOX.

HIS ATTORNEY.

United States Patent 3,195,795 CONTADIER Isaac L. Wilcox, Fulton, N.Y., assignor, by mesne assignments, to Phillips Petroleum Company, a corporation of Delaware Filed Aug. 20, 1963, Ser. No. 303,960 3 Claims. (Cl. 229-7) This invention relates to containers made of sheet material such as paperboard, and has to do particularly with the attachment of the end closure to the body of the container.

Several million of such containers are used daily for the retail packaging of liquid food products, such as milk. It is most desirable that the container embody a structural arrangement whereby an end closure, particularly a top end closure may be quickly sealed in liquid tight relation and remain so sealed during handling of the filled container, and at the same time be easy and convenient to separate, or open to permit the contents of the container to be poured therefrom.

In order to render such containers, when formed of paperboard, to be entirely impervious to liquid, and to permit sterilization of the containers prior to filling, they are coated with plastic material, such for example, as polyethylene. The end closure may be quickly and conveniently permanently closed, or permanently bonded to the body of the container by the application of heat and pressure, the thermoplastic polyethylene coating also acting as an adhesive for sealing the end closures to the body of the container. However, such bonding is of a permanent nature and the overlapping, or engaging portions of the end closure, or the body and the end closure cannot be subsequently readily separated, it being necessary to puncture, tear, or otherwise mutilate the sealed parts to provide for the opening of the container to remove the contents therefrom.

In order to provide for easy opening of the sealed container in some instances, an arrangement is employed to prevent a portion of the engaging parts from heatsealing together. This is accomplished by employing a sealed barrier of some form between confronting portions of the engaging or overlapping parts to prevent those portions of the parts from fixedly bonding together.

Also, when such containers coated with thermoplastic material are open, and the liquid contents poured therefrom, there is a tendency for the liquid to trickle, or run down the exterior of the container.

This invention has as an object a container formed of sheet fibrous material, such as paperboard coated with thermoplastic material to render the container impervious to liquids, and serving as an adhesive to seal the engaging parts of the container closure, the container of the invention embodying a unique coating arrangement, whereby an area of the engaging parts of the end closure, or the end closure and body are bonded together in a restricted area by the heat-sealing operation employed in closing the container, these engaging parts being bonded in such manner as to be entirely leak-proof, and yet the parts bonded in such area can be conveniently separated to provide a pour opening for the removal of the contents of the container.

The invention has as a further object, the employment of a coating arranged on the engaging, or overlapping parts of the container, which when the parts are separated provides for the elimination of any trickling, or run down of the contents on the outer surface of the container.

The invention consists generally of a container formed of sheet material having engaging parts coated with thermoplastic heat-scalable material for bonding the parts together. A portion of one of the parts is provided with a coating of material non-heat-sealable to the thermoplastic material on said other part, the portion of said other part confronting said portion of the one part having bonded thereto in a restricted area a material heatsealable to the coating on said portion of said one part.

The invention consists in the novel features and constructions and method hereinafter set forth and claimed.

In describing the invention, reference is had to the accompany drawings in which like characters designate corresponding parts in all the views.

In the drawings- FIGURE 1 is a view, in perspective, of a container embodying my invention.

FIGURE 2 is an enlarged, sectional view taken on line 2-2, FIGURE 1.

FIGURE 3 is a view, with the portion of the top closure, shown in FIGURE 2, separated from the side wall of the container.

FIGURE 4 is a plan view of the blank from which the container body is formed.

FIGURE 5 is a view, in perspective, of the top corner of the container body prior to the application of the top closure.

The container illustrated in the drawings is of the general type disclosed in Patent No. 2,470,984, to R. H. Horning, et al., May 24, 1949. It includes a body formed of paperboard, or like fibrous material. The body is formed is formed from the blank shown in FIGURE 4. The blank is provided with vertically extending scores 11 defining

side wall panels

12, 13, 14, 15 and 16. The blank is coated on both sides with thermoplastic material 20, the coating being bonded to the blank. The surface of the blank, constituting the outer surface of the container has printing applied thereto between the

lines

21, 22. The blank is formed with an incision 23 extending lengthwise of the blank, and being spaced slightly inwardly from one side edge thereof. The body blank is severed from a web moving continuously through the printing apparatus, and the printing cylinder, simultaneously with applying the printed material between the

lines

21, 22, prints a line 25 immediately above the incision line 23. This print line 25 extends laterally from one of the score lines, such as the score line 11, the print line extending approximately to the center of the

adjacent side panels

13, 14, see FIGURE 4. The purpose of the incision 23, and the print line 25 will be explained hereinafter.

The blank is folded on the score lines 11 to square tubular form with the free edge of the panel 16 overlapping the edge portion 27 of panel 12, and being heat-sealed thereto by the thermoplastic coating 20. A suitable bottom closure is bonded to the lower end of the tubular body. After the contents has been placed in the container, a top closure is sealed to the top end of the body. This top closure is also formed of fibrous material such as paperboard. The top closure is formed from a flat blank to provide a flat central area 29, dimensioned corresponding to the tubular body, and having at its periphery an upstanding flange 30 extending upwardly inside of the top portion of the body, and outwardly over the top edge of the body, and merges with a downwardly extending outer flange 31. The top closure is also provided on its inner surface with a coating 33 of thermoplastic material, heatsealable to the coatings 20 on the container body.

The

flanges

30, 31 form an inverted channel positioned over the top edge of the container body. Heat and pressure are applied to these flanges, whereby the flanges become permanently heat-sealed and bonded to the container body by the

coatings

20, 33.

In order to permit convenient opening of the closed container for the removal of the contents therefrom, as

set forth in the Homing patent previously referred to, a

F I i n Veneer 95f {D ED I corner portion of the channel structure of the top closure was not heat-sealed to the container body. The bonding of this corner portion of thetop closure was prevented by aseal barrier positioned. intermediate the corner por- 7 tion of the top closure flange, and the Contiguusportion.

of the container body. Such a seal barrierrna'y consist ofa strip ofsheet'materia'l 37, such as'rnetallic foil. The

foil'strip 37 is heat-sealed, and bonded .to the inner sur-* faces; of the closure flanges: 30, 31 by the coating 33, on

these inner surfaces. The opposite side of the seal barrier unintentional separation ofthe'parts.

rier strip. The print line '25 is applied to a restricted area of the container body, whereby the heat seal bond-- ing of the outer closure flange 31 to the body' is only in thisrestricted area." This restricted area of bonding of these engaging parts" is entirely sufiicient to prevent any On' the other hand, the restricted area does not require any additional effort in the opening'of the container." This is particularly true because of the'incision'line 23, which as previously pointed strip 37 'has applied to-it, a coating 40 of material that is non-heat-sealable' to the coatings on the body, and V accordingly, the foilistrip sea-l barrier prevents one corner portion of the top closure flanges from sealing to the container body. It will be apparentthat the non-scalable coating ,40 could be applied; directly to theinnersur'faces of the

top closure flanges

30, 31,:but that arrangement would require pattern,'or spot Jcoatingon the top closure,

or the body blank,if the non-scalable coating, were.ap-' plied thereto. It has beenfoundin practice, that the use I of the seal-barrier strip 37' with the release or non-scal able coating 44) applied thereto is the more" practical an. 7,

rangement.

It will be understood that the seal barrier. strip 3 7Jextendsabout acornerp'ortion of thexcontainer body, as the upper ends of 'the'panels ,13,'14,Iand preferably extends downwardlyon the outer side of the body below the flange 31 of the top closure, to provide'a free finger: grip tab portion for assisting in movingthe flange 31 outwardly fromthe container body, and swinging the, corner portion of the top cl'o'sure upwardly, as shown in FIGURE 3; to

provide. the corner. pour opening for the removal. ofthe.

contentsfrom the container The flat central po'rtion29 of the top closure may be provided with a score line43 extending diagonallyacros's the corner portion'of the top closure',;inwhich the seal barrier is" positioned, see FIG.- URE 1. factory separable top closure corner portion, which, under normal handling. of the containers, remains in leakproof engagement with the contiguous top corner portion The arrangement described, provides a satis} of the container body. -However, unusually rough hang dling of the filled container, or "the application of ap-- preciable pressure to thattop' corner portion ofthe conj tainer tends to. effect premature separation betweenv the j top closure, and'the container'at this onefsealed corner portion; If the container is of larger ,capacity, such as gallon or half gallomand it is picked up by grasping the top rim. of the container, the s'queezepres'sure at' the top may cause such premature leakage. However, this arrangement in general is particularly advantageousin that it provides for easy and convenient opening of thecontainer, andwhen thiscorner portion ofthe top closure is V separated from the container body, and swung upwardly to provide. the pour opening, that exposed top-edge of the container-body isste'rileinthat it has been previously J completely protected by the top closure flanges.

By my invention, I modify the arrangement described to prevent any premature separation ofthe topclosure from the container body without sacrificing the ease of" opening the container. I obtain this advantage'witho ut incurring any increase in the cost of the fabrication of the container. The print plate or cylinder for printing the exterior of'the body blank between the lines 21, .22,

simultaneously applies the print line'25 to theblank. The ink used in the printing operation after drying 'bonds firmlyto the thermoplastic coating 20 on the body blank, and

after drying, this ink is 'heat-sealable'to' the coating 40 on the seal barrier strip 37,.which as previouslyexplained is'bondedfto the inner surfaces ofthe'closure. flanges 30,

31,:hy thethermoplastic coatingZgS. In other.;Words, while the coating 40 onthe'sealbarrier'fij isnoni-heat- 1 sealable with the coatings20 on .thecontainer body, the print line 25 bonded tothe outersurface' of the container 'body ishea -sealablewiththe coating 40pm the seal barout, extends along the loweredgeof the print line 25. The print line 25 is permanently bonded-to the outer. coating 20 of the container body, and this coating in turn is permanently bonded to the container body, all whereby when the flange 31 of the top closure is swung outward- 1y, the-print. line 25 and; the coating 20. bonded thereto movewith the flange causing a separation of the fibers.

in the outerlayer. of the containerbody'. v

r .Itwiil be apparent that the; incision line 23 aids material- 1y in,-the starting ofthis fiberseparation. This action is illustrated in; FIGURE 3 of the drawings, showing the coatinglli extending above the incision: 23 havingbeen separated fronrthe containerbody, leaving the same with an'exposed fibrous surface, as indicated'at' 50. In other 7 words, the strength'of thejbond bctweenthe' printline 25 and the" coating 20 exceeds-the. strength of the paperboard; when? the top closure flange; :31: is intentionally moved-outWardlyfrom the container body forthe opening of the container, thisresulting in the" separation of. the" 7 layer fibers to which the body coatingZl) is bonded to.

separate from the paper-inthe sidewall of the container body. I have foundthis area of exposed fibers on the outer surface of the container body at the top edge thereof, over which the contents of the container are poured,

is effective to prevent any dribbling, or. ru'n cl own of the poured milk over the outer surface of the container body.

While the bonding of the print line 25 to the coatingi20 is sufficient to tear the coating from the containerbody,

the incision 23-assists greatly inthe'more'ready separation.

of the coating 29, and of the outer fibrouslayer of the container sidewall.

I The material for theicoating 20 may consist ofilow' density Alathon l5 polyethylene, manufactured and sold by E. I. du Pont de emours & Co., Inc., Wilmington, Delaware, Plastics Department. A material suitable for the coating ti on the seal barrier strip 37 may consist of the following: c r y 1 The ink used in printingv the exterior surface of the container body, and including the print' line ZS'may'be a'flcxographic. inkforrnulated'of the following materials:

Cellulose nitrate I, Pigment Natural resins Synthetic resins Waxcompounds r Proprietary .ethyl alcohol The coating 40 is applied Wet to the" seal barrier strip, and'upon drying, bonds firmly. thereto. The printing, in- ..cluding the print line-25, isappliedwet to theexterior surface of thecontainer body; and upon drying, bonds to the polyethylene coating'20. After drying, the print line 25 isheat-sealable to the coating 40.. Other, materials may be usedfor the coating 49 and the ink, if they are mutually heat scalable.

What I claim is:

i. A container formed of paperboard and having ongaging parts with contacting surfaces, the entire surface of one engaging part being coated with a thermoplastic material, the major portion of the contacting surface of said other engaging part being coated with like thermoplastic material for bonding the parts together, a strip of foil bonded to the remaining portion of said other part and having bonded to its surface confronting said one part,

a coating of material non-heat-sealable to the thermoplastic material on said one part, the surface of said one part confronting said foil being provided in a restricted area with a material overlying and bonded to said thermoplastic material on said one part, and being heat-sealable to the coating on said foil.

2. A container formed of paperboard, including a body member and an end closure member, said members having overlapping portions with contacting surfaces, the entire contacting surface of the overlapping portion of said body member being coated with a thermoplastic material, and the major part of the contacting surface of the overlapping portion of said closure member being coated With like thermoplastic material for heat-sealing the parts together, the remaining'part of the contacting surface of the overlapping portion of said closure member having bonded thereto a strip of metal foil, the surface of said foil confronting the overlapping portion of said body member having bonded thereto a coating, including nitro cellulose material non-heat-sealable to the thermoplastic coating on the body member, the contacting surface of the overlapping portion of said body member confronting said foil having bonded thereto in a restricted area, a

coating, including nitro cellulose material, heat-scalable to the coating on the confronting surface of the foil.

3. A container formed of paperboard and having first and second parts with contacting surfaces, the entire contacting surface of said first part being coated with a thermoplastic material, a portion of the contacting surface of said second part being coated with a like thermoplastic material, said materials serving to join said coated surfaces by the application of heat and pressure, the remaining portion of the contacting surface of said second part having adhered thereto a coating of material nonheat-sealable to the thermoplastic material on said first part, the contacting surface of said first part confronting said remaining portion of said second part being provided in a restricted area with a coating overlying said thermoplastic coating on said first part and being adhered thereto, said overlaid coating being heat-scalable to the coating adhered on the said remaining portion on said second part.

References Cited by the Examiner UNITED STATES PATENTS 2,328,579 9/43 Pelosi 2295.5 2,470,984 5/49 Horning et al. 229-7 2,471,017 5/49 Wilcox 2295.5 2,802,613 8/57 Boyd 229-7 3,012,707 12/61 Gray 229-51 3,096,918 7/63 Van Dyke et a1. 22951 FOREIGN PATENTS 562,5 86 9/58 Canada.

FRANKLIN T. GARRETT, Primary Examiner.

Claims

1. A CONTAINER FORMED OF PAPERBOARD AND HAVING ENGAGING PARTS WITH CONTACTING SURFACES, THE ENTIRE SURFACE OF ONE ENGAGING PART BEING COATED WITH A THERMOPLASTIC MATERIAL, THE MAJOR PORTION OF THE CONTACTING SURFACE OF SAID OTHER ENGAGING PART BEING COATED WITH LIKE THEREMOPLASTIC MATERIAL FOR BONDING THE PARTS TOGETHER, A STRIP OF FOIL BONDED TO THE REMAINING PORTION OF SAID OTHER PART AND HAVING BONDED TO ITS SURFACE CONFRONTING SAID ONE PART, A COATING OF MATERIAL NON-HEAT-SEALABLE TO THE THERMOPLASTIC MATRIAL ON SAID ONE PART, THE SURFACE OF SAID ONE