US3276671A - Paper wrapping having stretchable insert - Google Patents

Description

Oct. 4, 1966 D. L. FLEITMAN 3,276,671

PAPER WRAPPING HAVING STRETCHABLE INSERT Filed DSC. ll, 1964 'fNvENToR DEN/W5 L. FLE/WAN United States Patent O v 3,276,671 PAPER WRAPPING HAVING STRETCHABLE INSERT Dennis L. Fleitman, 1018 Eastern Parkway, Brooklyn, N.Y. Filed Dec. 11, 1964, Ser. No. 417,712 1 Claim. (Cl. 229-53) This invention relates to a paper wrapping having a stretchable insert running lengthwise of the wrapping. The term wrapping as used herein will denominate a tube or bag.

It is the primary object of my invention to provide a paper wrapping having a stretchable insert whereby the wrapping will distend under excessive tensile pressure.

It is another object of my invention to provide a paper Wrapping having a stretchable insert, of the character described, wherein the insert will expand transversely when excessive strain is applied to the wrapping so that bursting of the wrapping is prevented as would be the case if the stretchable insert were not present.

It is another object of my invention to provide a paper Wrapping having a stretchable insert, of the character described, wherein the wrapping has the configuration of a paper bag with the stretchable insert running between the mouth and bottom of the bag, so that when such a bag is loaded, handled, stacked, shipped or stored, the shocks, strain and tension naturally imparted to said bag in the course of such actions will be absorbed by the give of the insert whereby tears and rents in the bag are prevented.

It is a further object of my invention to provide a paper wrapping having a stretchable insert, of the character described, particularly suited for use in automated machine packaging of goods whereby excessive force applied lto the wrapping for example in forming the wrapping into. a desired shape for the goods, in ensheathing the goods with the wrapping, or in opening the wrapping to receive the goods, causes distension of the stretchable insert andfthereby prevents or deters failure of the wrapping.

It is an ancilliary object of my invention to provide a paper wrapping having a stretchable insert, of the character described, wherein said insert has the additional characteristic of elasticity so that after the insert has yielded to absorb excessive strain applied to the wrapping and t-hen said strain is removed, the paper wrapping will spring back into or towards its original configuration.

It is yet another object of my invention to provide a paper wrapping having a stretchable insert, of the character described, wherein the insert is elastic lso that the wrapping can snugly receive objects whose dimensions are slightly larger than those of the unstretched wrapping.

It is still another object of my invention to provide a paper wrapping having a stretchable insert, .of the character described, wherein the insert comprises only a comparatively small portion of the wall of the wrapping so that the inherent desirable characteristics of the wrapping such as its good tensile strength, low cost, conformability, light weight, and ability .to be stored in folded condition are not affected while the extendability of the insert enables the wrapping to perform its intended containing function in an improved manner.

It is a further object of my invention to provide a paper wrapping having a stretchable insert, of the character described, wherein the wrapping with said insert is of simple configuration which can be manufactured by mass-production methods in a speedy and efficient manner at an economical cost.

In accordance with the teaching of my invention, I provide a paper wrapping having a stretchable insert which distends to absorb excessive suddenly or gradually ap- 3,276,671 Patented Oct. 4, 1966 ICC plied forces bearing on the wrapping when the Wrapping is being utilized in the packaging of commodities, or subsequently when the wrapping is enclosing commodities and is being handled, stored or transported. I have found that during the utilization of conventional paper wrappings, excessive tensile force applied to the wrappings causes rents or tears therein which render the wrappings useless. The aforesaid excessive pressure is usually of a transitory nature in the form of a sudden impact or shock to the wrapping, which causes said wrapping to burst and fail. For example, when a wrapping in the form of an open-mouthed paper bag is being rapidly loaded with bulky articles, the articles may strike the wall of the bag or in association with articles already in the bag distort the wall of the bag so as to generate an excessively high though only momentary tensile force which leads to failure of the bag. vThe same may happen when the wrapping is quickly loaded with granular or powdered materials, wherein the sudden pressure of a large load of said material may cause excessive strain on the wrapping.

In another example, in automated high speed packaging machinery wherein inserting and spreading jaws spread the mouth of a paper wrapping open to receive goods which are to be placed therein, the spreading movement of the jaws beyond intended limits due to play or wear in the machinery may impact and tear the wrapping. The same problem arises when the contents of a wrapping shift in transit or during handling, or when external force is applied to the wrapping as when fthe wrappings, with commodities therein, are piled in stacks. In the foregoing instances, some measure of yieldability in a wall of a wrapping would permit the same to expand in a direction parallel to the direction of applied tensile pressure in order to absorb any impact without splitting the wrapping.

Notwithstanding the desirability of adding lthe characteristic of yieldability in response to applied shock or impact to a paper wrapping, said characteristic must not interfere with the normal containing function of the wrapper. That is, if an entire wrapping were formed from a more yieldable material, said wrapping would unduly stretch, distort and s-ag whenever the weight of its contents bore on the wall of the wrapping. Also, to form a wrapping entirely out of a yieldable materal which would have most of the desirable characteristics of conventional wrapping would unduly raise the cost of the wrapping and price such an Iarticle out of the competitive m-arket.

To add yieldability in response to shock and impact to the wrapping while yet preserving the conventional characteristics of paper wrapping, I provide the mentioned stretchable insert for the wrapping. The insert is linear and elongated, that is, lon'g as compared to its width and is formed from imperforate sheet material. The insert is oriented with respect to the wrapping with its length .in a direction generally perpendicular to the circumferential i.e., gir-thwise direction in which the excessive tensile force will usually be applied. Generally, the excessive force will be applied circumferentially of the wrapping so that the insert will run between the end walls, i.e. the mouth and bottom of the wrapping. The insert may terminate at said end walls or may continue part way across one or both end walls.

In order that the conventional characteristics of the paper wrapping be preserved, the insert comprises a strip, i.e. a relatively small elongated portion of the wall of the Wrapping in which it is located and preferably less thanv 35% but at least 5% of the width of said Wall of the wrapping. Said inser-t is formed from flexible imperforate sheeting significantly more yieldable than the paper or other material from which the remainder of the wrapping is made. The material of the strip is yieldable in at least a 'girthwise direction of the wrapping and preferably is 'yieldable bidirectionally, i.e. parallel and perpendicular to the length of the strip. In other words, in its preferred form, the strip has abiaxial or two-way stretch, AThe 'strip is made an integr-al part of the Wall of the Wrapping by having its edge margins rmly secured to adjacent borders 'of the wrapping, and the strip is desirably located at Ithe seam in the wrapping.

' In yet another aspect of my invent-ion, I provide a paper wrapping including an insert which is elastic as well as yieldable in order that after it has stretched due to impact or shock, said insert is biassed back to its contracted position of repose. This may be desirable from lthe standpoint of attractiveness of the appearance of the wrapping when it encloses goods. Moreover it enables the wrapping to snugly ensheath -its contents. The elasticity of an rinsert integral with the wrapping will main- -tain a snug t even when the goods slightly vary in their relevant dimensions.

Other objects of my invention will in par-t be obvious 'and in part will be pointed out hereinafter.

My invent-ion accordingly consists in the features of construction, combination of parts and arrangement of components which will be exemplified in the paper wrappings hereinafter described and the scope of which will lbe indicated in the appended claim.

In the dra-wings -in which various possible embodiments of my invention are illustrated,

FIG. 1 is a three quartered perspective View of a paper bag with a stretchable insert in accordance with the teaching of my invention,

FIGS. 2 and 3 are fragmentary sectional views of the Wall of the bag containing the stre-tchable insert, taken substantially along the l-ine 2-2 of FIG. 1 and showing said Wall, respectively, in normal or repose condition and in a transversely extended condition;

FIG. 4 is a fragmentary sectional View of the bottom corner of the bag, taken subs-tantially along the line 4-4 of FIG. l;

FIG. 5 is a view similar to FIG. 2 but illustrating the 'insert formed from crepe paper; and

FIG. 6 is a three quartered perspec-tive View of a paper tube with opposed stretchable inserts therein, the tube having i-ts end walls overlapped to enclose commodities therein.

Referring now to the drawings, and, more particularly, to FIGS. 1-4, the reference numeral 10 designates a Wrapping in the form of a paper bag constructed -in accordance with my invention, the bag comprising a walled container 12 including as an integral part thereof an elongated linear stretchable insert 14. The term walled container as used herein and in the claim is intended to denote in a very -broad sense receptacles having the general characteristics of non-rigid open-mouthed paper conta-iners (open-mouthed for insertion of goods although usually the mouths are closed after goods are inserted in the receptacles) of a variety of sizes, shapes, configurations and materials. The Iterm encompasses such artrecognized types as heavy duty paper sacks, normal and light duty sacks, industrial bags and covers, and preformed bags including the flat, square, automatic, Satchel, pouch style and contour-shaped types. Also included in the term are Wraps and over-wraps, that is, flexible containers made from sheet stock and formed in place by automatic packaging machinery around the contours of a product or a primary package. My invention is most likely to nd its best acceptance in the industrial and commercial packaging eld.

The walled container can lbe formed from lany lightweight, low-cost, flexible, strong-in-tension, non-stretchable material from which such containers are conventionally made. The term non-stretchable indicates an elongation by ASTM D 882 of not greater than 7%. The material is desirably chosen from the paper and texplied.

The material from which' the container is formed can be plain, plast-ic lined, coated, impregnated or laminated and preferably is paperv in the Weight range of from 25 to 200 lbs., this being the weight of a ream of 24,'in. by 36 in. sheets of the material, the same having'a stre-tch of about 11/2% to 3%. It is to be understood that the paper selected is conven-tional for any given size or use ofthe wrapping.

The type of walled container referred to nds particular use in the packaging of bulkly and hard-tvo-handle objects. The advantages of speed, economy and low weight in the use of these containers make them preferable over the more traditional .alternatives of rigid containers or hand wrapping. Also, less storage space is necessary, and when appropriate loading machines are used, faster packing speeds are attained. The various uses include mattress bags for enclosing mattresses as well as inner and box springs, bags for compressible products as foam rubber cushions and pads, can bags for packaging empty metal or libre cans, and bags for building materials including plywood sheets, Wallboard and acoustical tiles. From the natureof `the commodities to be enclosed by my wrapping, it is evident that severe shocks and impacts will be vimparted to the wrapping 'during the loading, handling, storing and shipping thereof, imparting intense though primarily momentary stresses to the wrapping wall.

The stretchable insert 14 is, as has been mentioned, linear and elongated, having a .width substantially less vthan its length. The insert is desirably oriented in a direction with respect to the wrapping so that stresses applied to the wrapping will assume a direction generally transverse to the length ofthe insert. Generally, the insert will be parallel to a dimension of the wrapping and will usually run lengthwise of the wrapping. That is to say, the insert generally lies in a direction perpendicular to the circumference, i.e. girth of the wrapping. In Wrappings of the type illustrated in FIGS. 1-4 that are preformed with an open end or mouth 16 and4 have a rectangular closed end wall or bottom 18, .the insert is in the form of an elongated strip that bridges an elongated slot in the container and which runs between said mouth and bottom, generally perpendicular 4to the mouth. The effective length of the strip terminates on one end at the mouth and at the other end at the bottom, and said strip is of a substantially uniform width and cross-section'. The effective width of the strip, that is, the width of the strip between linear zones of connection to the wall of the container 12 does not exceed 35% and is not less than 5% of the width of the wrapping wall in which it is located.

If the wrapping has a generally cylindrical conguration with a continuous single Wall, each half of the wall may be considered the wall in which the strip is located, for the purpose of determining the effective width of the strip.

The material from which the insert is formed is thin, ilexible, tough, yieldable, imperforate film sheeting, having a high tear strength. The term stretchable used in reference to the insert means that the insert is significantly and measurably more elongatable without failure than the material from which the walled container 12 is made. Specifically, stretchable as used herein denotes an elongation of at least 60% byASTM D 882 and with no upper limit., Materials with an elongation of as much as 600% are acceptable.

In the preferred form of my invention, the material is bidimensionally stretchable so that it can distend cir# cumferentially, i.e. girthwise of the bag and also length-` wise of the insert. If the material is Ionly stretchable in a single direction, the insert must be oriented so that `its` direction of stretch .is circumferential of the bag. The` insert can, for example, be made of crepe paper havingl a stretch of 60% Vto 300% ASTM D 882. This type of crepe paper is known as secondary crepe in the paper field and the creping is performed during the paper making operation, after the paper is fully formed and dry. By means of known techniques, kraft papers of up to 80 lbs. cans be creped. Such papers may be creped to stretch in one or two directions.`

The insert preferably is made of a synthetic resin, thermoplastic or theromsetting, in imperforate thin film sheeting having the' properties of fiexibility, yieldability of at least 60% high impact strength and high tear strength. These include polyethylene with an elongation of from 60% to 600%, polypropylene with an elongation of from 200% to 500%, polyvinylchloride with an elongation of from 60% to 500% and rubber hydrochloride with an elongation of from 200% to 500%. Other desirable films with a minimum elongation of 60% ASTM D 882 can be selected from the charts of composite and noncomposite films, pp. 179-180, in the October 1964 issue of Modern Packaging.

It is appropriate at this point to mention that an insert width of less than of the width of the wall in which the insert is located is deemed to provide a resul-tant yieldability which is insufficient f-or commercial usage even when the material utilized for the strip has a high percentage of yieldability. I believe this may be due in part to the small maximum stretch which can be obtained from such a narrow insert and partly due to the inability of such a narrow insert to absorb the energy of impact stresses to which the wrapping may be subjected.

On the other hand, where the insert width exceeds about 35% of the width of the wall in which it is located, the bag tends to be incapable of maintaining its own shape to a sufficient degree for proper utilization thereof, e.g. to be compatible with existing machine packing equipment.

A yieldability (stretchability) of less than 60% is commercially unsatisfactory due, I believe, to the inability of such materials to assimilate shock imposition of stress.

It is, therefore, my present belief that a wrapping having an effective width of at least 5% of the width of the wall in which it is located with a yieldability which at least includes a girthwise direction of stretch and with a yield-ability of at least 60% is a minimum requirement necessary to practice my invention.

It is advantageous under many circumstances to utilize materials such as aforesaid which also are Ipellucid so that the contents of a filled Wrapping can readily be seen.

The elongated margins of the side edges 20 of the yieldable strip 14 are secured to affiliated linear borders 21 of the slot in the walled container in any conventional manner resulting in a permanent connection. In the illustrated embodiment, the st-rip is disposed internally of a broad wall of the container where the overlapped seam normally would be located and its edges are overlapped by the borders of the slot in the container.

The strip can be secured to the paper by the use of an adhesive chosen from the Vegetable, animal, or synthetic classes. The strip can also be heat sealed to the container, stitched to the container, or secured by the use of adhesive tape.

In `FIGS. 1-4, my invention is illustrated in a rectangular reinforced-bottom automatic type paper bag 12. The strip 14 as well as the broad wall of the container in which it forms an insert is folded underneath the paperboard floor 22 of the bag and then adhered to said oor. Said figures show by way of example a large industrial 80 lb. kraft bag intended to contain 18 two gall-on empty paint cans. The bag is 2 ft. 8 in height and is y18 in. x 22 in. in its circumferential dimensions, the strip being disposed in the 22 in. wall. The effective Width of the strip 14 in repose is 3 inches, the same being formed from polyethylene film of 2 mil thickness, seven inches in total width.

FIGS. 2 and 3 are cross-sections of the wall of the container in, respectively, reposed or unstretched condition and partially expanded condition.

lFIG. 5 illustrates another embodiment of the iuvention wherein the strip 14 is formed from crepe paper.

Where the strip is lformed from an elastic material, e.g. rubber hydrochloride, after shock has been absorbed Aby elongation of the strip, it will tend to resume its original repose condition. This is valuable where the outward apearance of the wrapping is important, wherein a snug fit is desired between the wrapping and its contents, and where repated tensile stresses are expected to be absorbed by the wrapping.

In FIG. '6, another embodiment 10 of my paper wrapping is illustrated, this form 4being Iwell adapted for use in autom-ated packaging machinery. The wrapping here is shown as it appears after formation from fiat sheet material about a rectangular box by an automated packing machine. Said wrapping at this time is in the contiguration of a tube 12 having two parallel like strips 14, each strip being integral with and comprising an insert in an opposed elongated side wall of the tube. The tube has closed end walls formed by tucking the side Walls and overlapping and fastening the end flaps 32, 34. Of course, the previously discussed specificati-ons for the paper wrapping apply t-o this embodiment 10 as well. It may be noted in passing that the strips 14" continue around the edge of the tube and run across the end walls of the tube toward one another. Thereby, some limited yieldability is imparted to the end walls of the tube.

It should also be noted that, in general, by virtue of the ability of the stretchable insert to absorb shock, stress and impact, the strength of the remainder of the walled container may be lowered without a reduction in the over-all capability of the wrapping. This is because the strength of the Walled container need only be sufficient to bear normal loads While the yieldable strip can absorb unusually high transient stresses. Therefore, through the use of the present invention, -obvious economies can be effected without a reduction in the quality of the wrapping.

It thus will be seen that I have provided paper wrappings which achieve the several objects of my invention and which are well adapted t-o meet 4the conditions of practical use.

As various possible embodiments might be made of my above invention, and as various changes might be made in the embodiments above set lforth, it is to be understood that all matters herein described or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.

Having thus described my invention, I claim as new and useful and desire to secure by Letters Patent:

A paper bag for commodities such as mattresses, inner and box springs, metal and ber cans, plywood sheets, wall board and acoustical tiles, sai-d bag being adapted to absorb applied shock and impact without failure, said bag comprising:

(a) a ring of walls formed of non-stretchable flexible paper;

(b) said ba-g having Ian open mouth and .a closed bottom;

(c) one Wall having a slot therein running the entire length of the bag from the mouth t-o the bottom thereof, and

(d) an elongated linear stretchable insert formed yfrom imperforate -sheet material integral with the container, bridging the slot and running coincident with the slot;

(e) the width of `the insert constituting between about 5% and about 35% of the width of the wall of the bag in which it is located;

(f) the insert being formed from a synthetic resin film having an elongation and direction of stretch 7 8 girthwise 0f the bag of from about 60% to about 2,617,504 11/1952 Meyers 150-52 X 600%, 2,624,246 1/ 1953 Bryce 229-53 X 2,992,117 7/ 19611 Rosen et a1. 229-87 X References Cited by the Examiner 3,181,773 5/ 1965 Jelling et a1 229-53 X UNITED STATES PATENTS 5 FOREIGN PATENTS 1,803,712 5/ 1931 Lab'ombard et e1 206-7 476,985 9/1951 Canada 1,857,010 5/1932 Avery 229-53 776,018 5/1965 France. 1,962,071 6/1934 Greene 229-53 921,016 1/ 1947 France.

1,970,848 8/19'34 Grant 229-53 10 607,133 8/1948 Great Britain. 2,046,848 7/-1936 Royal 229-87 2,158,755 5/1939 Hodgam JOSEPH LECLAIR, Plmw'y Exdmmer.

2,475,052 7/1949 LROsen 229-87 D. T. MOORHEAD, Assistant Examiner.

Images