Title:
Container
United States Patent 2307902


Abstract:
This application is a continuation in part of our co-pending applicattionQ erial No. 36,772, filed August 19, 1935, now Patent No. 2,177,918 issued October 31, 1939,.and riltes to bags or other containers, formed of tlhiflexible sheet material, and adapted, for use in the packing, shipment,...



Inventors:
Vogt, Clarence W.
Lakso, Eino E.
Application Number:
US28597039A
Publication Date:
01/12/1943
Filing Date:
07/22/1939
Assignee:
Vogt
Primary Class:
Other Classes:
383/66, 383/119, 383/120
International Classes:
B65D5/60; B65D33/02
View Patent Images:



Description:

This application is a continuation in part of our co-pending applicattionQ erial No. 36,772, filed August 19, 1935, now Patent No. 2,177,918 issued October 31, 1939,.and riltes to bags or other containers, formed of tlhiflexible sheet material, and adapted, for use in the packing, shipment, storage and dispensing of liquid, plastic or other material.

Containers of the above type, when made entirely of thin flexible trasprent material such as "Plioflm" are somewhat diffcult to handle especially wien filled, because the extreme flexibility and slight elasticity of this material are apt to develop leaks at the corners and seams especially when subjected to rough treatment. The forming of the end.aeals and seams is by the application of heat and pressure, and it is desirable to protect the material to prevent it from sticking to the heated member by which sealing heat pressure is applied. Furthermore, direct application of sealing heat to the flexible transparent material might cause overheating of said material.

One object of the present invention is to provide a container of thin flexible transparent material, free from the disadvantages above referred to, but nevertheless capable of being conveniently and economically manufactured in quantity by automatic machines.

Another object is to provide a container of thin flexible transparent material, which is flat when collapsed, and which assumes a substantially rectangular cross-section when filled. This rectangular formation is highly desirable, since it permits the filled container to be readily in- 3X serted in, and to substantially fit the usual rectangular carton or storage compartment.

As a feature of the present invention, the container comprises a tube of thin flexible transparent material, having a reinforcing paper sheet 4( or other analogous substantially opaque sheet material secured to at least one side wall of said tube.

As a further feature, the transparent tube when collapsed has infolded side sections between a 4 pair of opposed flat panels, one or both of which are covered with a reinforcing paper sheet, while the infolded side sections remain uncovered.

As a further feature, the paper sheet extends outwardly beyond the side edges of the trans- 5 parent infolded sections to form marginal extensions which protect the folds from abrasion.

This paper sheet.imparts a certain degree of desirable rigidity to the container, and forms a backing through which the sealing heat can be 5 applied to the superposed layers of transparent material during the process of manufacture.

This paper sheet also protects the underlying layer of transparent material to which it is attached, and the longitudinal corners of the container against abrasion, puncture or other injury caused by rough or careless treatment of the container.

As a further feature, the container is provided at both ends with transverse seals, which anchor the inner fold edges of the infolds at said seals to limit outward distention of said infolds when the container is filled. The length of each seal is substantially the same as the width of the reinforcing paper sheet, which is substantially equal to the width of the side flat panels of the filled container. This paper sheet covers, one side of each seal, so that the longitudinal outer sides of the infolded panels are anchored by adhesives or by fusing to said paper sheet at the end seals. This anchoring of the flexible material at the sections indicated, together with the reinforcing and stiffening paper, serve to restrain and conrtne distention of the walls of the container, so that it will assume a rectangular crosssection when filled.

Various other objects, features and advantages of the invention will be apparent from the following particular description, and from an inspection of the accompanying drawing, in which: Fig. 1 is a perspective of one form of flexible container embodying the present invention, and shown filled and sealed, Fig. 2 is a transverse section taken on line 2-2 i of Fig. 1, but showing said bag partially collapsed, Figs. 3 and 4 are transverse sections through other forms of expanded containers respectively, embodying the present invention, Fig. 5 is a fragmentary perspective view mne 0 end of another form of container embodyi-.. the present invention, and shown in collapsed condition, Fig. 6 is a fragmentary perspective view of the upper end of another form of bag, embodying the present invention, and shown filled and sealed, an outer carton for said bag being shown partially broken away to better reveal the construction, and Fig. 7 is a perspective view of the tube from 0 which the bag of Fig. 6 is made.

It must be understood, that in the drawing the several sheets or strips are shown of exaggerated thickness to facilitate a clearer disclosure of the parts.

5 In the form shown in Pigs. 1 and 2, the bag comprises sheets II and 13 of impervious flexible sheet material, which may be sealed by heat and pressure, or by the use of adhesive or solvents.

For Instance, it may be material sold under the name of "Pliofilm," which is made from a chlorinated rubber compound, and which is thermoplastic and readily vulcanized or sealed at a temperature of approximately 115° C., so that overlapping sections thereof may be sealed together by application of heat and pressure. Other an- I alogous thin flexible transparent sheet material might be employed, as for instance, heat-sealable "Cellophane," or even "Cellophane" which is not heat-sealable, where it is satisfactory or convenient to employ adhesive in forming the seams. I The sheet II of "Plioflm" or other material referred to has its side sections 12 heat-sealed to the edge portions of a narrower sheet of "Pliofilm" 13 along its entire length to form the tube.

The sheet 1 is tucked inwardly from the sides 2 of the sheet 13 to form infolds 14, two of such infolds being shown on each side. These infolds 14 are shown narrow, so that the inner fold edges of one pair of infolds do not abut or overlap the inner edges of the opposite pair of infolds, but 2 are spaced a substantial distance from said latter edges.

Adhesively or otherwise secured to the "Pliofilm" sheet 13 to form a laminated wall therewith is a reinforcing sheet 15, made of paper or other flexible substantially opaque sheet material, which will not be injuriously affected by the application of sufficient heat and pressure to effect sealing, fusing or vulcanizing of the "Pliofilm". In order that the corners of the bag along the side edges of 3, the sheet 15 be protected when the bag is flled, said sheet 15 extends beyond the side edges of the "Pliofilm" sheet 13 to form marginal extensions 16, and portions of the side sections 12 of the "Pliofilm" sheet I project outwardly beyond the side edges of said sheet 13, and are directly glued, cemented or autogenously welded at A to said marginal extensions. Such sealing by attachment of the sheet II directly to the paper sheet 15 at the corners has a reinforcing effect, which will compensate for any weakening resulting from heating and softening of the "Pliofilm" at the corners. Cemented or otherwise secured to the panel portion of the "Pliofilm" sheet II opposite to the sheet 13 is a sheet 18 of paper or analogous material. This paper sheet desirably extends beyond the outer edges of the infolds 14, so that when a filled container is placed in a tray or compartment, the marginal extensions 20 of said strip beyond said infolds will fold along the side walls formed by said infolds 14, and thereby protect the longitudinal corners of the bag from direct contact with foreign matter, which may have collected in the corners of the tray compartment.

This paper sheet 18 as well as sheet 15 also serves .toreduce the possibility of injurious abrasion or 60 "acidental puncture of the "Pliofilm" faces of the bag to which they are applied.

• The bag may be formed as a continuous tube, which is progressively collapsed and sealed longitudinally at the edges, and transversely at spaced points along the length thereof, and which is then transversely cut intermediate of the ends of the sealed portion, so that the portion of the sealed area on one side of the line of severance forms the bottom seal 21 across the entire width 70 of the bag, while the portion of the sealed area on the outer side of the line of severance forms the side seals 22 in the top of the next succeeding bag, said side seals being formed by the fusing of the infolds 14 together, and to the opposed panel sections of the sheets II and 13, and forming an opening therebetween through which the bag may be filled.

After the bag has been filled, the opening thereof between the infolds is permanently sealed by heat sealing together the facing "Pliofilm" linings of said opening along a transverse strip 23, extending to the side seals 22. This sealing is effected by heat and pressure, so that all the superposed layers of "Pliofilm" are autogenously bonded together.

During the heat sealing operations referred to, the heated members are applied directly to the 5 paper sheets 15 or 18, and not to the "Pliofilm" layers. Although the end seals consist of two thicknesses of "Pliofllm" at the center, and seven thicknesses of "Pliofilm" at the sides, the paper sheets 15 or 18 prevent overheating of the center 0 portion of the "Pliofllm" sheets during heat seal ing.

The two paper sheets 15 and 16 on opposite side of the container serve not only for the purpose referred to, but also serve to protectively Scover the seams between the sheet II and the sheet 13, and if desired to carry advertising or other printed matter.

When the container is empty and collapsed with the two opposite transparent sides infolded, Sall of the exposed surfaces of the container will be completely covered and protected by the flat, stiffening, or reinforcing sheets 15 and 18 on the other two sides.

The fiat bottom and top seals 21 and 22, exStending across the full width of the collapsed container, anchor the edges of the infolds 14 at said seals against outward distention, the anchoring points of said infold edges to the upper side seals 22 being Indicated at B. When the container is filled, this anchoring feature restrains the outward distention of the infolds 14, so that they do not extend any substantial distance beyond the side edges of the paper sheet 15.

Between these seals 21 and 22, the infolds 14 are anchored at A along the longitudinal side edges thereof to the paper sheet 15 as already indicated. These lines A of anchorage extend to the end seals 21 and 22, and continue along said seals to the points B. This Interconnection of anchorage lines provides a restraining encirclement, which confines distention of the side walls of the container when filled, so that it will assume a generally rectangular shape.

The paper sheet 15, covering the two seals 21 and 22, serves not only as an anchoring means for the outer side edges of the infolds 14 as already indicated, but due to its comparative stiffness co-operates with the other paper sheet 18 to assist in forming and maintaining the filled container in rectangular shape. A container so shaped will readily fit in the rectangular carton in which the container is usually packaged, and lends itself easily to multiple storage in a tray even without an outer carton.

In one method of filing the container, a filling funnel is inserted into the opening between the side seals 22, and is withdrawn after the filling is completed. The seal along the strip 23 is then formed between the side seals 22 to close the opening.

Another advantage of the present construction is that this opening automatically closes when the filling funnel is removed. Due to the comparative stiffness of the paper reinforcing sheets and 18, tending to straighten said sheets out into flat position, the two opposed flat panel sections of the filling opening automatically come together to close after the filling funnel is removed. This facilitates the sealing of said opening, as it permit the heat sealing device to be applied directly to the container without requiring A any special means to first close the mouth thereof.

In the construction of Fig. 3, a sheet 25 of "Pliofilm" or analogous thin flexible transparent sheet material has secured to one surface thereof a pair of strips 26 of substantially the same material as the sheet 25, but preferably of a grade of material which is somewhat tougher or harder.

The strips 26 are each secured adjacent to their opposite edges to the sheet 26 by narrow sealing lines or areas 21, preferably effected by the application of heat and pressure. The body portion of each strip 26 is preferably unattached to the body of the sheet 28. The edge portions of the 2g sheet 25 beyond the strips 26 are brought together in overlapping relationship, and heat sealed to form a longitudinal lap seam 28, so that said sheet 25 will form a tube. The laminated strips as described may be of infinite length, and may be progressively formed and sealed as already described with reference to the construction of Figs. 1 and 2.

The portion of the laminated sheet covered by the strips 26 will form two opposite walls of the tube and of double thickness. The double thickness of the other two walls of the tube are formed by strips 30 and 30a of paper or analogous stiffer, tougher and desirably opaque sheet material, and these may be brought into proper assembly with the formed tube after the sealing of the seam 28, although the strip 30a may be applied to the sheet 25 before the latter is folded around a mandrel into tubular form.

The strips 30 and 30a are sealed in place preferably substantially throughout their area, either by an adhesive coating on the inner surface of said strip, or by partial softening of the inner layer during heating, although other sealing means may be employed, and protectively cover the seams 27 and 28. The side sections of the tube formed by the double thickness of the strips 26 and the sheet 25 are tucked in by single or double infolds respectively when the bag is collapsed, so that the transparent section of the tube is protected and concealed by the paper strips 36 and 30a as in the construction of Figs. 1 and 2..

The ends of the tube are sealed in the manner similar to that described with reference to Figs. 1 and 2 to form the completed bag, with the anchoring features by which the bag assumes a rectangular cross-section when filled, and the stiffening features by which the filling operation is facilitated. In the construction of Fig. 3, the longitudinal anchoring of the "Pliofilm" material is to both paper sheets 36 and 36a near the side o6 edges of said sheets, so that a more effective control of the rectangular shape of the container is obtained than with the construction of Figs. 1 and 2.

The strips 30 and 60a are desirably slightly 6 wider than the tube in expanded condition, so as to present edge portions 31, extending slightly beyond the other two side walls, and serving to protect the corners as shown in Fig. 3. The strips 26 are of such width and the shape of the expanded container is such, that the edge portions of the said strip which are sealed to the strip or sheet 25 fold around the corners. Thus the seams 21 are covered by sheets 30 and 36a, and the latter are 71 secured to such edge portions, so that there is formed an outer casing made up of the strips 26, 31 and 36a, and an independent inner casing formed solely by the sheet 26, the two casings being permanently secured together.

In Fig. 4 is shown an alternative construction, in which an inner "Pliofllm" sheet 35 is bent to form three sides of the container, and an outer "Pllofilm" sheet 1 is also bent to form three sides.

By turning inwardly the edges of each sheet 35 and 31, and assembling the sheets with the channels facing in opposite directions, and heat sealing each of the inturned edges of one sheet to the adjacent sheet, a tubular casing is formed having two opposite sides, each formed of two layers of the thin flexible, transparent sheet material. The strips 31 and 30a of the stiffer opaque material are applied and glued in place to cover the single layer sides, and to cover, conceal and reinforce the seams 21. This container when collapsed has the sides infolded like the construction of Fig. 3, to bring the opposed panels carrying the strips 30 and 3la into close overlapping position.

In ig. 5 is shown a form of bag, in which a strip 40 of "Pliofilm" or analogous material has its opposed longitudinal side edges 41 heat sealed together in overlapping relationship to form a fin, projecting from the middle of one of the panels 42. A sheet 43 of paper or analogous material is adhesively or otherwise secured to the strip 46 on the panel 44, and two narrow paper sheets 46 and 41 extend over and are adhesively secured to the strip 46 on the respective segments of the panel 42, with the adjacent sides 41 of said paper sheets extending over and attached to the respective faces of the fin. The side edges of the sheet are infolded when the bag is collapsed, and the paper sheets 43, 45 and 46 have their side edges 48 extending around the corners of the tube, to reinforce and protect said corners against possible injury.

The bottom of the bag has a seal (not shown) extending across the full width thereof. At the top, a seal similar to the spaced side seals 22 of Fig. 1 may be provided, or the top may be sealed across its full width, and the filling opening formed in some other part of the bag. In this manner, the bag has anchorage features similar to those described with reference to the construction of Figs. 1 to 4, to assure formation of the bag into rectagular cross-section when filled.

In Figs. 6 and 7 is shown a type of bag, which is shown as nested in an outer comparatively stiff carton. In this construction, the bag comprises a strip 50 of "Pliofilm" or analogous mam terial, having its opposite edges heat sealed together to form a longitudinal lap seam II. This tube in collapsed position forms infolded sides, and a pair of opposed panels 52 and 5c, the seam 51 extending along the latter panel. Adhesively secured to and covering this panel 53 including the seam i1 is a sheet 54 of paper or analogous material, wider than said panel, and having its projecting edge sections 55 wrapped around the corners of the container to protect said corners.

SThe tube structure shown in Fig. 7 is hermetically sealed at its lower end across the full width thereof substantially as already indicated with reference to the other constructions, and may be filled through its upper open end while In a suit0 able outer carton 51 made of comparatively stiff cardboard as shown in Fig. 6. This upper end can then be suitably heat sealed as shown in Fig. 6, so that the flexible container protected by the outer rectangular carton 56 may be safely shipped 5 and stored.

The bag may be first sealed at the ends, and then filled through an opening 60, which may be plugged or closed In any suitable manner.

The end seals, in conjunction with the paper sheet 54, afford the anchorage features by which the bag will assume a substantially rectangular cross-section.

As many changes could be made in the above construction and many apparently widely different embodiments of this invention could be made without departing from the scope thereof, it is intended that all matter contained in the above description or shown in the accompanying drawing shall be interpreted as illustrative and not in a limiting sense.

Having thus described our invention, what we claim as new and desire to secure by Letters Patent is: 1. A container comprising a tube of thin flexible transparent sheet material, said tube being approximately of rectangular cross-section when expanded, and having two opposed sides infolded and the other two flat sides close together when collapsed, and an outer sheet of stiffer substantially opaque material secured to and protectively covering one of said latter sides, and having its side edges extending beyond the edges of said side.

2. A container comprising a tube of thin flexible transparent sheet material, said tube being approximately of rectangular cross-section when expanded, and having two opposed sides infolded and the other two sides close together when collapsed, and outer sheets of stiffer substantially opaque material secured to and protectively covering said latter sides, while the infolded sections of said tube remain uncovered by said stiffer sheets.

3. A container comprising a tube of thin flexible transparent sheet material, said tube being approximately of rectangular cross-section when expanded, and having two opposed sides infolded and the other two flat sides close together when collapsed, and an outer sheet of stiffer substantially opaque material secured to and protectively covering one of said latter sides, and having its side edges extending laterally beyond the corresponding longitudinal corners of said tube to protect said corners.

4. A container comprising a tube of thin flexible transparent sheet material, said tube being approximately of rectangular cross-section when expanded, and having two opposed sides infolded and the other two flat sides close together when collapsed, and sheets of stiffer substantially opaque material secured to and protectively covering said latter sides, while the infolded sections of said tube remain uncovered by said stiffer sheets, the outer side edges of said latter sheets extending laterally beyond the corresponding longitudinal corners of said tube to protect said corners.

5. A container comprising a tube of "Pliofilm," rectangular in cross-section when expanded, and having two opposed sides infolded and the other two flat sides close together when collapsed, and 6 outer paper sheets secured to and protectively covering said latter sides, while the infolded sections of said tube remain uncovered by said paper sheets, the outer side edges of said paper sheets extending laterally beyond the corresponding longitudinal corers of said tube to protect said comers.

6. A container comprising a tube of thin flexible Stransparent sheet material, having two opposed infolded panels between a pair of opposed flat panels when collapsed, and having a transverse seal at the bottom, extending substantially across the full width of said collapsed tube, said seal anchoring thereat the inner fold edges of said infolded panels to restrain substantial outward distention of said latter panels beyond the sides of said flat panels, and an outer sheet of stiffer substantially opaque material secured to and protectively covering one of said flat panels, and of approximately the width of said panel, and extending substantially across the full width thereof.

7. A container comprising a tube of thin flexible transparent sheet material, having two opposed infolded panels between a pair of opposed fiat panels when collapsed, and having a transverse seal at the bottom extending substantially across the full width of the collapsed tube, and a seal at the top extending to the sides of said tube, said seals anchoring thereat the inner fold edges of said infolded panels to restrain substantial outward distention of said latter panels beyond the sides of said flat panels, and an outer sheet of stiffer substantially opaque material secured to, protectively covering, and of approximately the width of one of said flat panels, and extending substantially across the full width of said collapsed tube.

8. A container comprising a tube of thin flexible transparent sheet material, having two opposed infolded panels between a pair of opposed flat panels when collapsed, and having a transverse seal at the bottom extending substantially across the full width of said collapsed tube, said seal anchoring thereat the inner fold edges of said infolded panels to restrain substantial outward distention of said latter panels beyond the sides of said flat panels, and an outer sheet of stiffer substantially opaque material secured to and protectively covering one of said flat panels, and extending substantially across the full width of said seal, said tube being secured to said outer sheet longitudinally along the outer sides of said infolded panels.

9. A container comprising a tube of thin flexible transparent sheet material, having two opposed infolded panels between a pair of opposed flat panels when collapsed, and having a transverse seal at the bottom extending substantially across the full width of the collapsed tube, and a seal at the top extending to the sides of said tube, said seals anchoring thereat the inner fold edges of said infolded panels to restrain substantial outward distention of said latter panels beyond the sides of said flat panels, and an outer sheet of stiffer substantially opaque material secured to and protectively covering one of said flat panels, and extending substantially across the full width 5 of said collapsed tube, said tube being secured to said outer sheet longitudinally along the outer sides of said infolded panels up to said seals.

CLARENCE W. VOGT.

EINO E. LAKSO.