US2736656A - Method of packaging - Google Patents

Description

Feb. 28, 1956 J. M. MARSHALL METHOD OF PACKAGING Filed Feb. 11. 1952 2 Sheets-Sheet 1 INVENTOR. J0///V M. MFJ/V/MA ffiQ/Vf);

Feb. 28, 1956 J, M. MARSHALL METHOD OF PACKAGING 2 Sheets-Sheet 2 Filed Feb. 11, 1952 I N VEN TOR. ,f/V/V M MAPSWALL United States Patent 9" METHOD OF PACKAGENG John M. Marshall, Patehogue', N. Y., assignor to Kraft Foods Company, Chicago, 111., a corporation of Delaware Application February 11, 1952, Serial No. mom

1 Claim. c1. saw-m veniently served in package form by restaurants, railroads and airlines. The packages prepared in accordance with my method may also be used for containing a variety of other materials and substances, particularly Where such materials and substances are distributed in sample quantities.

It is an object of the invention to provide a method of packaging whereby substantially sealed packages are constructed which may nevertheless be opened easily and without special implements.

It is another object of the invention to provide a package which is simple and inexpensive to manufacture a simple and inexpensive method for manufacturing and filling packages.

Still other objects will be obvious from the following description. A preferred method of packaging will now be described with reference to the accompanying drawings and the features forming the invention will then be pointed out in the appended claim.

In the drawings:

Figure 1 is a fiat view of one end of a blank strip suitable for forming the package of the invention;

Figure 2 is a schematic perspective illustrating the method of forming the package;

Figure 3 is a plan view of the completed package on an enlarged scale, with part of the cover broken away to show the structure below;

Figures 4 and 5 are sections on the respective lines 44 and 5-5 of Figure 3;

Figures 6 and 7 are views similar to Figure 4, but illustrating formation of the package under different conditions; and

Figure 8 is a perspective showing the manner in which the package is opened.

The package may conveniently be formed from a strip 1 of suitable plastic, thermoplastics being preferred, and plastic, such as a vinyl chloride acetate (Vinylite) being suitable. Successive lengths l are formed into containers and then cut off from the strip 1 as described below.

The method of forming the package is indicated schematically in Figure 2. The strip 1 is subjected to the action of heat, pressure and suitable forming dies to form a succession of cups having side walls 3 and bottoms 4, a margin 2 of undeformed strip material being left around these cups. The cups may now be filled with jam or jelly 5 or with other desired material and the cover 6 applied as from a roll 7. The cover material is preferably a relatively elastic plastic material such as a rubber hydrochloride (Pliofilm) and is sealed to the border strip 2 surrounding the individual cups containing the material 5 by the application of heat and of the package.

2,736,656 Patented Feb. 28, 1956 pressure. Thereafter, the cup packages as formed are severed from the strip, as indicated in the case of the right hand package in Figure 2, and are ready for shipment and use.

It is preferred that the heat sealing of the cover 6 to the border flange 2 of the package extend over a wide surface area (roughly from the phantom line '10 of Figure 3 outwardly to the edge of the border 2). The two plastic materials involved being immiscible under ordinary conditions, the seal may be formed under suitable heat and pressure so as to provide a hermetic seal and yet permit peeling cover 6 from border flange 2 without difliculty and without tearing the cover. The cover strip 6 is preferably slightly wider than the strip 1 so as to overlap at least one edge of the border 2 of the package, as indicated at 8, thus facilitating gripping with the fingers for opening the package by peeling off the cover in the manner indicated in Figure 8. The cover may also overlap slightly at the opposite edge, as indicated at 9, it being preferable to use a slight excess width of cover material in order to avoid reduction in the sealed area between the cover and the border flange 2 Along the other two sides of the package the co-ver and flange 2 are sheared off flush with each other. This shearing action tends to create a sharp corner capable of inflicting a serious cut. However, since the cover 6 and edge of the border flange 2 are flush along two edges, and the edge of the cover 6 protrudes over the edge of border flange 2 along edge 8, the natural method of opening as indicated in Figure 8 eliminates, to all intents and purposes, any possibility of injury on a sharp corner.

The package should be made from a blank 1 of relatively thin material. In the case of a package which is two inches square in its maximum dimensions, material about one one hundredth of an inch in thickness or somewhat less is found suitable. In the drawing, the walls 3 and bottom 4 of the cup which is formed will have a combined area about double the area of the blank material out of which they are drawn, so that the side walls I 3 and bottom 4 of the cup'are reduced on the average to about one half the thickness of the original blank 1 and of the surrounding flange 2. The bottom 4 and adjacent lower part of the side walls 3 will normally be somewhat less than half the thickness of the original blank and may be about three to five thousandths of an inch in thickness. The Pliofilm cover 6 is preferably even thinner and may be around two thousandths of an inch or somewhat less in thickness.

It will be understood that the cup formed from the blank need not be square or rectangular in shape, but may be circular or of any other convenient shape which may be preferred. it will also be understood that the depth to which the cup is drawn may be varied somewhat, as for accommodating a half ounce, three-quarter ounce or one ounce of material in a container of the size indicated.

Where jams or jellies are being packaged, it is preferred to fill the package with the material at about F. instead of the much higher temperatures heretofore used in packaging such materials. Figure 6 illustrates schematically the cooling. of a container filled as indicated in Figure 4, the condensation of water vapor and contraction of the air concaving the top 6 as indicated and also the bottom 4 and walls 3 of the cup. It is found that the package withstands the resulting concaving without difliculty and may be shipped without any unusual or special precautions and stored for relatively long periods of time. the package will withstand refrigeration where desired,

the resulting further contraction of the air space above In particular, it is found that the contents causing no difficulty. It has been found that the package will also withstand reduction of exterior pressure, such as is encountered in flight at altitudes of five to ten thousand feet, the cover 6 bulging upward and the walls 3 and 4 also bulging to a smaller extent as necessary, without producing any harmful separation of the cover 6 from the flange 2 or impairing the seal.

Despite the fact that the closure between the cover 6 and flange 2 of the package is hermetic and will withstand all normal service conditions, the cover may be peeled off, starting with one edge or side as indicated in Figure 8, with no ditficulty, thus making the package very convenient in use.

It will be understood that while only a few cups have been shown in Figure 2, there may be large numbers of such cups in the strip in the various stages of manufacture, as indicated, as is found convenient in particular manufacturing operations.

This application is a continuation in part of my prior application Serial No. 152,958, filed March 30, 1950, which issued as Patent No. 2,649,392.

What is claimed is:

The method of packaging individual food servings which comprises forming an elongated first strip of thermoplastic material into a longitudinally spaced series of cups while leaving a horizontally extending border flange about each cup, successively filling the cups with a food material, applying a continuous second strip of thermoplastic material to said first strip to provide covers for said cups and border flanges, the width of said second strip being greater than the width of said first strip, so that an edge portion of said second strip extends beyond a marginal edge of said first strip, heat sealing said second strip to said first strip along said border flanges at a temperature such that a low strength hermetic seal is effected between said strips, and cutting the sealed strips transversely of said strips between said cups to provide a plurality of individual sealed packages each having a cover which includes an edge portion extending beyond a marginal edge of the associated border flange, said extending portion providing a finger grip for peeling said cover from said associated border flange.

References Cited in the file of this patent UNITED STATES PATENTS 571,521 Heberline et a1 Nov. 17, 1896 1,689,018 Froidevaux s Oct. 23, 1928 1,995,712 Irvine Mar. .26, 1935 2,012,529 Eldredge Aug. 27, 1935 2,155,445 Pittenger et al Apr. 25, 1939 2,276,744 Smith et al Mar. 17, 1942 2,452,218 Bemis Oct. 26, 1948 2,513,852 Donafrio July 4, 1950 2,527,919 Drangle Oct. 31, 1950 2,530,306 Land Nov. 14, 1950 2,553,513 Denison et al. May 15, 1951 2,649,392 Marshall Aug. 18, 1953

Images