US2359190A - Bag - Google Patents

Description

BAG

T. M. AVERY x-:rAL

Filed Jan. 11, 194s Zzglsept. 26, 1944.

Wrilllhrsillrufnusnnd/ Patented vSept. 26, 1944 UNITED 4STATES PATENT OFFICE BAG True M. Avery, Glens Falls, and William H.

Bokenkrogennudson Falls, N." Y., assignors to y Union Bag Paper Corporation, Hudson Falls, N. Y., a corporation of New Jersey Application January 11, 1943, Serial No.472,ll24

19 Claims.

food products, such for example, as dehydrated' foods, packed in ther bag or container willbe maintained in a dry state, and products, such -for example as coffee, packed in the bag'or containe;` will be kept in a moist state and the volatile or other desirable constituents thereof will be retained, and products subject to deterioration or other adverse alteration under the influence of air, moisture or other atmospheric or exterior conditions will be protected therefrom.

Another object is to provide an improved closure for bags or similar containers which-will be sift-proof and thus prevent the escape of powdery or granular material packed therein.

-Another object is to provide relatively simple and `effective means forreinforcing the closures in opened condition, showing a section `of the bottom closure structure'on the line 4 4 of Fig. 3; and

Figure is a vertical section, on an enlarged scale, of*V the lower portion of the improved bag in opened condition, the section being taken through the'bottom closure on the line 5,-5 in Fig. 3.

Similar parts are designated by the same reference characters in the several figures.

The present invention is applicable to bags of the so-called automatic and Satchel-bottom types employing the so-called "diampnd fold in the formation of the closure thereof, and to other forms of containers having a closure of similar type. Y

` Preferably, and as shown in the present inof bags of the automatic, Satchel-bottom and similarconventional types, whereby the strengthv of such closures is greatly increased.

A further object of the invention is to provide a bottom closure structure possessing some or all of these advantages, which may be produced effectively by heat sealing during the manufacture of the bags on bag machines of .usual or conventional form, thus enabling bags embody.-

'lng the improved bottom blosures to be manufactured substantiallyy with the same speed and facility, and at no substantial increase in cost as compared with bags of the usual or conventional forms. In the accompanying drawing, which shows the preferred embodiment of the invention- Figure 1 shows a portion of a-,pleated and ilat` tened bag tube an end of which is opened into a so-called diamond fold, illustrating 4the man ner of inserting a sealing member during formation of the bag'y closure in accordance withthe present invention; e A Figure 2 is a view similar to Fig. 1, but showing the sealing member inserted into the closure str ucture; l

Figure 3 is a view of the completed bag bottom; Figure 4 is a perspective view, on an enlarged scale, ot the lower portion of the improved bag walls of the tube.

y gap 9 between-them,

stance, the invention is applied to the bottom vclosure of bags of the automatic type. Such bags may be manufactured in the usual manner and upon bag machines of the usual or well known forms from, a tube l having pleats or tucks 2 in its longitudinal edges. The tube preferably comprises an outer wall 3 formed from a web of ordinary paper such asthat usually used in the manufacture of paper bags, and a coextensive inner wall or liner 4 formed from a web of materiakwhich is'impervious to moisture and air'ror other gases, or substantially so, and which is preferably thermoplastic or heat scalable, such', for example, as wax paper which is l,wax-coated and thermoplastic. on its surface the inner su'rface of the tube or bag.

,An end-of the tube formed of` such outer and inner walls, while in flattened form, is opened into a diamond f old, as shown in Fig. 1, in the manner usual in the manufacture of bags of the automatic type upon bag machines of the usual or well known form, thus folding inwardly the pleated sides of this portion oi.l the tube to form sideflaps 5 and 6, and closing flaps l and 8 which are continuations of the lfront and back In forming the bottoms vof bags of this type as just described, the inner'or free edges of the ilaps 5 and 6 are usually separated and form a and 'although in the completion of a bottom closure ofthis type. 'l is folded down upon and pasted to the, underlying flaps 5 and 6, and the ap '8 is folded down upon and pasted to-underlying portions of the and flap 1, crevices have been left between the flaps which were -in .communication with the gap 9 and through whichl moisture or volatile or other constituents ofthe bag contarte which forms inserted beneath the inner and '6 in a suitablemanner,

. ed on its other inner 4 posed on. the

v are preferably 5 and 6 'as l' 'thelnner portions of these tinuous lines careas of the liner could escape, or through from the atmosphere could enter the bag and thus cause deterioration of the contents thereof. Also, such crevices and een have heretofore permitted powdery or granular material to sift out of the bag. Other gaps or leakage points have heretofore existed at the ends of the slits which form the tabs 'le and te, and in the regions where the adhesive squeezed away in the direct bight of the hinge formed along the told lines il and eb when the naps l and ti are folded down upon the naps E and These faults inl loess oi this type as heretofore made are overcome by the present invention. According to this invention a sealing strip le, composed oi air and moisture 'proof material, is portions of the ii'aps Sand 5, preferably after the diamond fold has been made and before the naps Vl and are folded to complete the bottom, the sealing strip bridging the gap 9 between 'the inner edges of the naps 5' and -6 throughout its length/and preferably also extending into or overlapping partially, at least,

secured to the preferably, however, by heat sealing. When a'liner is employed which is provided on its inner side with a thermoplastic" coating which will bond, by heat sealing, to an uncoated surface on the'sealing strip., it is preferable to employ a thermoplastic coating on the of which faces the flaps 5 and but is not so coatsurface which will be exbag, a flexible strip wax o n one side being when the thermoinside of the of unratedv paper coated with suitable for the purpose, and plastic coated inner surface oi the' liner will not bond, by heat sealing, to an uncoated surface of the sealing strinboth Sides of the sealing strip thermoplastic coated. A inserted beneath thel flaps 2,I and is secured to flaps along the con- II and I2, and the inner faces of the portions of the liner within the aps 1 and '8 are -secured tothe outer and inner surfaces of the respectivend portions of the sealing strip and to one another along the continuous lines and I4, the end portion of the liner which forms part of the bottom closure of the bag being thus'sealed completely around al1 of its edges. Ll'hese lines of` sealingare preferably made by applying heat and the lines ii and l2, while tihe lligg d form as shown n atne inner surface of the sealing strip supported out of contact with the underlying which form portions of the inas'by a plate placed beneath the sealing strip, thereby heat-sealing the outer thermoplastic coated surface of the sealing strip throughout the lines Il and i! to the inner ther- The sealing strip is shown in Fig.

bottom is in its Side 0f mi the support for the sealing strip, pressure along the lines I3 and i4, thereby heat-sealing' .to one another the opposed contacting inner thermoplastic coated outer surface there pressure to the flaps ilrst along l 2, and prefersurfaoesJof thoseyportions of lines Hand ,tothef :assenso which moisture or air V portions of the sealing strip which extend into the flaps 1 and 8.

By supporting inner surface is underlying portions of seals are made along the lines Il4 and i2,`espe cially when the sealing strip isV thermoplastic coated on both surfaces, the heat and pressure applied along the line's li and l2 to heat-seal the flaps 5 and 6 to the sealing strip will not heat-seal the inner surface of the sealing strip to those parts of the inner surfaces of the liner which form portions of the inside of the bag, thus avoiding interference with opening of the bag bottorninto its proper rectangular form when the baz is ed.

the sealing strip lil so that its held out of contactv with'the The bottom closure is completed by folding and,

adhesively securing the flap 1 to the previouslyl infolded iiaps i and l and folding and adhesively securing the ilap 8 tothe iiap 1 and the underlying portions of the flaps 5 and 6 not covered by the flap 1. Ordinary paste or adhesive is preferably used for thus securing the naps 1 and l, it being preferable to secure the extension tabs 1n and 8a of theseilaps to the corresponding portions of theinner liner which overlap them by applying paste or adhesive, for example, to those portions of the web which forms these portions of the outer ply or the inner liner, so that the outer and inner plies or the tabs 1"l and I will be secured together, and the paste or adhesive for securing the naps 1 and in closed position may be applied in to the flaps 5 and t while these flaps are in the pleats, closure formed by a diamond form shown in Fig. 2.

Although the invention is'shown applied in ,the present instance to a v bag of the automatic type having pleats or tucks in its edges, it will be obvious that the invention is also applicable to bags of the Satchel-bottom" type without and to any other type of bag having s', i fold, and also to other forms of containers having closures.A

Also, while the invention is applicable with particular advantages to bags having an inner nner coated on its inner surface with a thermoplastic material, it is to be understood thaty the invention may also be applied tosingle wall bags the inner surface of which is coated with an air-and moisture p'roof and thermoplastic material. or to which thermoplastic material is applied on those areas of the flaps in which the heat-seals are to be made as hereinbefore described.

The improved closure provided by the present invention will not only seal the contents from the escape of moisture or volatile substances and entrance of moisture or air which would cause deterioration or loss of desirable qualities thereof. but it also provides a sift-proof closure which'will effectively prevent the loss of powdery or lar substances packed inthe bags. The air ani napsand nrmly connecting their inner edges and similar forms of the bag while the heatI the usual manner to these flaps and .v

extending into and folded with said'omsmg naps,

vthe inner and outer plies of each closingfiap back walls and over said side naps, and a sealing A member heat sealed tothe inner surfaces of said side flaps and rmly connecting them, and extending into said closing flaps between the plies thereof and heat-sealed therein, the inner and outer plies of each closing flap being heat-sealed to one another and to interposed portions of said sealing member. Y g

3. A bag closure comprising flaps folded inwardly from its sides and closing aps folded from its front and back walls, said side and closing flaps having heat-scalable inner surfaces, and a sealing stripc having a heat sealable outer surface heat-sealed to the inner surfaces of the side iiaps and bridging a gap between the latter, end portions ofthe sealing strip overlapping the closing flaps, and the inner surfaces of the closing flaps being heat sealed to said end portions of the sealing strip.

4. A bag closure comprising aps .folded inwardly from its sides'and closing flaps folded fromgits front and back walls, each of the closing iiaps embodying innerandouter plies, the

inner surfaces of the side flaps and the opposed surfaces of the inner plies of the closing naps being Aheat-scalable, and a sealing strip having.

a thermoplasticlmaterial on its outer surface lheat-sealedv to the inner surfaces of the side iiaps and having portions extending Ninto the closing flaps, the inner surface of the sealing strip exposed fto the interior of. the bag being devoid of thermoplastic material but the inner and outer surfaces-of the portions of the sealing strip extending into the closing aps being heat sealed to the'innr plies ofthe closing aps,

and the inner plies of each closing flap being heat-sealed to one another along a line adjacent to the fold line of the respective closing flap.

5. A closure for a bag the inner-surface of L which is air and moisture proof and heat-sealable, comprising flaps folded inwardly from the sides of the bag and closing flaps folded from the front and back walls thereof and onto the siderilaps, the closing iiaps having inner and surfaces of the side flaps across outer plies, and a sealing strip composed of air. .and moisture proof material both surfaces -of which are heat-scalable' and the outer surface of which is heat-sealed to the inner surfaces of the side'fiaps continuously across the width thereof, and the inner plies of each closing flap being heat sealed to the inner and outer sury faces of said" sealing strip and to one another continuously across the width vthereof on a line adjacent to flap'. l i

6. A closure for a bag having an outer wall ,and an inner air and mgoisture proof liner the inner surface yof .which is providedwith a thermoplastic coating, comprising `flaps -folded' from the sides of the bag land closing flaps-'folded from the front and back walls'thereof and onto the sideiiaps andY embodying innenand outer plies of said outer' wall and inner liner, and a strip of air andA moisture proof material, said strip being provided on at least its outer surface with a thermoplastic coating which is heat-sealed" to the inner surfaces of the side naps, and the ends of said strip extending into closing naps '.60 the fold line of the respective closing.

neV

^ closing flaps folded on ing inner and outer plies of the liner, and an air between the plies of the liner, and the plies off the liner in the closing flaps being heat-sealed to one another and to both sides of said strip along lines parallel and adjacent to the fold lines of the closing flaps.

7.7A closure for a. bag having an outer wall and an inner air andmoisture proof liner, comprising flaps folded inwardly from the sides'ol",

the bag and closing flaps folded from the front and back walls thereof 'onto the side folds and embodying inner and outer plies of the liner, the

and the plies of the portions of the liner forming parts of the closing naps beingf heat 'sealed' to ode another and to the respective sides of said s p.

8. A bag comprising an outer wall and an' inner air and moisture proof liner having a thermoplastic inner surface, said wall and liner having a diamond fold forming side fiaps and multiple closing flaps folded.

across the side folds and heat-sealed to the inner the Width thereof, portions of said strip extending into the closing flapsbetween plies of the liner and having its inner and outer surfaces respectively heatsealed thereto, and plies of the liner in the closing flaps being heat-sealed to one another' across the width of the closing flaps.

9. A bag comprising an outer wall of paper and an inner air and moisture proof liner`having a thermoplastic inner surface, said outer wall and liner being diamond folded to form side flaps, and

the side flapsand embodyand moisture proof strip having a coating of thermoplastic material on its outer side which'is heat-sealedA to the inner surfaces of the portions of the nner forming tions of said strip extending into the closing-naps between the plies of the liner therein. and said plies of the liner` in tho closing naps being neatsealed to one another and to both surfaces of said `strip along lines parallel and adjacent to the fold lines of the closing'naps.A

10. A bag of the automatic type comprising an outer wall' of paper and an .inner air and moisture proof liner having a thermoplastic inner surface, said outer wan and liner being -folded to form side naps extending toward one another, and closingrfiaps folded onto theside flaps and one upon another, and each embodying'ainner and p outer plies of the liner, and an' air and moisture across the adjacent portions proofstrip extending of the side'naps and having'a coating of thermo.-

i plastic material on its outer surface which is heatsealed to the inner surfaces of the side naps, the ends of the strip extending into the closing iiapsl between` the plies of the liner therein, andi the plies of the liner in the closing aps being" heatsealed to one anotherani of the ends of the strip.

`11, A bag comprising an outer, wall of poner i and aninner air and thereon, and a stripV of au- Vand moisture proof material extendingparis of the side flaps, por- 4 to the respective sides.

`to the inner surfaces f thereof heat-sealing i of the side of'sald of an outer 'and moisture proof liner having a a thermoplastic inner surface, said outer wall and liner being folded to'form side flaps, and closing flaps folded on the slde flaps and embodying inner and outer plies of the liner, and an air and moisture proof strip extending across the width of the -v side flaps and having a coating of thermoplastic material on its outer surface which is `heat sealed of the portions of the liner forming parts of the liner in the closing flaps being heat sealed toone another, and the portions of the liner forming parts of the; side and closing flaps being secured 'adhesively to paper forming parts of said flaps, and the closing flaps being secured adhesively to one another and to the side flaps.

12. The method of forming a. bag closure, comprising diamond folding an end of a bag -tube having atherinoplastic inner surface tc form a pair of side aps and [closing flaps, inserting a strip IYhaving a thermoplastic surface thereon beneath the side flaps in a position to bridge a gap between them, heat-sealing the inner surfaces of the side flaps to the outer thermoplastic surface of said strip while leaving the inner surface of said stri-p j aledto the surfaces of the bag which are exposed to the interior thereof, and folding and securing the closing flaps to one another and to the side aps.

13. The method of forming a bag closure, comprising diamond folding an end of a bag tube having a thermoplastic inner surface to form a pair of side aps extending toward one another and a pairof closing flaps each composed of pairs of inner and outer plies, inserting a strip thermoplastic surface thereon beneath the side flaps in a position to bridge the adjacent edges the inner surfaces of the side l flaps to the outer thermoplastic surface of said 'strip while the inner surface of said strip and the surfaces of the bag exposed to the interior thereof are in non-sealing relation, heat sealing the plies in each of the closing flaps toA one another, and folding and securing the closing flaps to one another and to the outer sides of the side flaps.

14. The method of forming a bag closure, comprising diamond folding an end of a bag tube composed of an outer wall of paper and an inner air andmoisture proof liner having a thermoplastic inner surface to form a pair of side flaps extending toward one another and a pair of closing flaps, inserting a strip which is thermoplastic on one only beneath the side flaps bridge aspace between them and the plosing flaps. heatpsealing the inner surfaces of those .portionsof thel said strip while avoiding sealing of the inner surstrip to the surfaces of the bag which are exposed to the interior thereof, heat sealing plies'of those portions of the liner which form parts of the closing flaps Both surfaces of said strip, and folding and securing the closing naps to one another and to the side naps.

15. The method of forming a bag closure, comprising diamond folding an end of a 'bag tube coinwall of paper and an inner air thermoplastic innersurface to form a pair o f side flaps extending toward one another and l a pair of closing naps, inserting a strip which is thermoplastic on both surfac beneath the side naps in a position to bridge a space between'them andto extend into the portions of the outerwall ofhaving a in a position to to extend into toone another-and to side aps, the plies of the inner surfaces of those portions the closing flaps, heat-sealing the inner fsurfaces of those portions of the liner which form parts of the side flaps to the outer s vrface of said strip while preventing sealing of the inner surface of said strip to the surfaces of the bag which are exposedto the interior thereof. heat-sealing plies of those portions of the liner which form parts of the closing flaps to one another and to both surfaces of said strip, and folding and securing the closing flaps to one another and to the side naps. i

16. The method of forming a bag closure, comprising diamond folding an end of a bag tube composedof an outer wall of paper and an inner air and moisture proof liner having a thermoplastic inner surface to form a pair of side flaps extending toward one another and a pair of closing flaps, inserting a strip beneath the side flaps in a position to bridge a space between them and to extend into the closingiiaps, heat-sealing the' of the liner which form parts of the side flaps to the outer surface of said strip while supporting the inner surface of said strip out of sealing relation with underlying portions of the bag, and then removing such 1 support for the strip, heat-sealing plies of those portions of the liner which formparts of the closing flaps to one another and to both surfaces of said strip, and folding and securing the closing flaps to one another and to theside flaps.

17. A closure for a moisture proof container comprising opposed flaps folded toward one another and closing naps folded over the opposed naps and having inner and outer plies, and a moisture proof sealing strip of a length greater than the width of the opposed naps and of a width less than that of the closing' flaps, said strip being sealed to opposed flaps, and the inner and outer plies vof the closingiiaps being sealed to one another and to the respective opposite surfaces of said strip.

18. A moisture proof container'havingj at an end thereof diamond-folded side flaps. and a pair'V of closing flaps folded over the side flaps and comprising-inner and outer plies. and a moisture proof sealing strip connecting the inner margins f of the side flaps and extending across the inner vvposite sides. of the Y which extend across liner which form parts flaps to the thermoplastic surface of surfaces thereof and between the closing flaps, the plies of the closing flaps being sealed to one another and to the respective'opstrip 'oncontinuous linesy the widths of the closing flaps, and the strip being sealed tothe inner surfaces of the side yiiaps on continuous lines which join the sealing lines on the closing flaps.

19. A bag comprisinga w'ali composed of moishaving at one end op-fv ture proof material and posed flaps folded toward one another and closing flaps folded over and secured to .said opposed I lxrles.v

flaps, the closing flaps each having innerand outer plies, and a moisture proof sealingstrip V.'

connecting the .inner edges of the opposed naps and lextending across the inner/surfaces and between the plies of the closing naps, the plies of the-closing naps being heat-sealed to one another and to of the sealing strip on linea which extend transverseiy of the closing mpc. and the winamp being heat-sealed to the inner surfaces o`f theopposed naps on dlines 'raux u. Aimar. wmum'n. nomxaoosa.

the inner surfaces of the Y plies of the the respective-opposiv te \surfaces which-Join said

Images