BACKGROUND OF THE INVENTION This invention relates to a flexible bag that can be repeatedly opened and resealed. In particular, it relates to a bag that has at least two wires fixed to at least one side of a bag that are not parallel when they are on the same side of the bag.
Many dry, solid products, such as snack foods and cereal, are sold in flexible plastic bags. Since all of the product within the bag may not be used when the bag is initially opened, it is necessary to close and re-seal the bag. Sealing the bag helps to preserve the freshness of the product, prevents it from accidentally coming out of the bag, and prevents contaminants, insects, and vermin from going into the bag.
Bags may be manufactured with a variety of different types of seals. For example, some plastic bags have plastic zippers (“Zip-Loc”), where a protuberance on one side of the bag is pressed into a groove on the other side of the bag. While this provides a tight seal, it is sometimes difficult to line up the protuberance with the groove and it is difficult to seal the bag without using both hands.
Other bags are sealed with wire ties that are stuck at one spot to the neck of the bag or are supplied with the bag. To seal the bag, the neck is twisted, the tie is bent around the twisted neck, and the ends of the tie are twisted together. However, sometimes the tie can fall off the bag and become lost. Also, the tie is at a fixed location on the neck and cannot be easily moved down the neck as the bag is emptied. Thus, if the bag is almost empty it will still be sealed at the top of the bag, enclosing an unnecessary amount of air within the bag, which will make the product become stale faster.
Bags can also be sealed using clamps or clips that are separately purchased. These require rolling up or folding up the opening of the bag, then applying the clamp or clip to the folded portion. Alternatively, the neck of the bag can be twisted and several loops of a rubber band can be placed over the neck. However, clamps, clips, and rubber bands may not always be available, especially if the bag is opened at a remote location, such as on a hike or while camping. Also, when a clamp or clip is used, the bag cannot be sealed by twisting the neck, which may be a more desirable seal for some bags.
SUMMARY OF THE INVENTION I have invented a re-sealable bag that is inexpensive and comes with a built-in seal. The seal consists of at least two wires that extend at least partly between the top and the bottom of the bag. The wires on any one side of the bag are not parallel (as they are, for example, in U.S. Pat. No. 3,537,636), which keeps the bag rolled-up tightly across its entire width, not just at the positions of the wires. It is also easier to roll up the bag when the wires are not parallel because the wires do not form two bulky coils of wire as they do when they are parallel. Rather, the wires in the rolled-up bag are spread out across the bag.
The wires may be fixed along their entire length to the bag, so they cannot come off the bag or become lost. Also, they may be enclosed in plastic so that they do not come into contact with the contents of the bag. Unlike prior seals, the re-sealable bag of this invention is unique in that it can be sealed either by twisting the neck of the bag or by rolling up or folding up the neck.
While prior bags require several steps to seal, the bag of this invention can be more quickly sealed, in a single step. For example, bags sealed with ties require two twisting motions, one to twist the neck of the bag and the other to twist the tie, while the re-sealable bag of this invention can be sealed with only a single twist of the neck. Sealing the bag by rolling up or folding up the neck also requires only a single step and there is no need to search for and apply a clamp, clip, or rubber band. Unlike bags sealed with a tie stuck to the neck of the bag, the bag of this invention can be sealed anywhere along the length of the wires. Thus, if the bag is almost empty, the neck can be twisted near the bottom of the bag, or rolled up to the bottom of the bag, to exclude most of the air and preserve the contents for a longer time.
BRIEF DESCRIPTION OF THE DRAWINGSFIG. 1 is a side view of a certain presently preferred embodiment of a laid flat re-sealable paper bag according to this invention having two wires crossed in a diamond pattern and fixed to the outside of one side of the bag.
FIG. 2 is an isometric view of the bag shown inFIG. 1, after it has been filled and sealed by rolling up the top.
FIG. 3 is an isometric view of another certain presently preferred embodiment of a re-sealable bag according to this invention having two non-parallel wires fixed to the inside of one side of the bag, where the bag is sealed by rolling up the top.
FIG. 4 is an isometric view of a further certain presently preferred embodiment of a re-sealable plastic bag according to this invention having two parallel wires on opposing sides of the bag, where the bag is sealed by twisting the top.
FIG. 5 is an isometric view of a still further certain presently preferred embodiment of a re-sealable plastic bag according to this invention for holding bagels that has two non-parallel wires on opposing sides of the bag.
FIG. 6 is an isometric view of the bag shown inFIG. 5, after it has been sealed by twisting the neck of the bag.
DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring toFIGS. 1 and 2,re-sealable bag1 is made of paper, but it may also be made of other flexible materials, such as plastic, cloth, or net-like materials.Bag1 may have a variety of shapes and sizes, but it is preferably rectangular in shape when it is laid flat (FIG. 1).Bag1 has two opposingparallel sides2 and3 and a parallel top4 andbottom5.Bag1 is open only at top4, and the opening at top4 is preferably the same width assides2 and3. While this invention is applicable to bags of almost any size and shape, it is particularly suited for bags that are rectangular when laid flat, where the distance between top4 andbottom5 is about 8 to about 18 inches and the distance between the twoedges6 is about 3 to about 12 inches.
Fixed tobag1 by means ofadhesive tape7 are at least twowires8 that extend in a direction between top4 andbottom5. Preferably, exactly 2 wires are used as one wire is not adequate to form a good seal and more than 2 wires are usually unnecessary.Wires8 may be fixed to the outside of the bag, as shown inFIGS. 1 and 2, but are preferably fixed to the inside of the bag (FIG. 4) so that they do not interfere with the design on the outside of the bag and are less noticeable.Wires8 are preferably fixed tobag1 along their entire length, not just at a single location, so that they adhere to the material of the bag and force it to conform to the shape the wires are bent to when the bag is closed.
Wires8 should be capable of being repeatedly bent and un-bent without breaking so thatbag1 can be repeatedly opened and re-sealed.Wires8 should bend easily, with little force, and should hold the position they are bent to without springing back to the un-bent position. Wires having a gauge between about 20 to about 25 are usually suitable, with the heavier gauges being used for heavier bags. The preferred wire is 24 gauge floral wire (Hillman), which is used to support flower arrangements, as it works very well for most bag sizes. Steel wires are preferred, but wires made of other materials, such as copper, aluminum, alloys, etc. may also be used. The wires are preferably insulated or enclosed in plastic so that they cannot be contacted by users or by the contents of the bag.
Wires8 may extend along the length ofbag1 from opening4 at the top of the bag all the way to the bottom of the bag, as shown inFIG. 3. Preferably, to save on wire and prevent the consumer from contacting the ends of the wires,wires8 are spaced about 2 to about 3 inches from the top and bottom of the bag, as shown inFIGS. 1, 2, and4.
The bag may be sealed by rolling up the top of the bag, as shown inFIGS. 2 and 3, or by twisting the top of the bag, as shown inFIG. 4. If the bag is to be sealed by rolling up the top of the bag, the wires are preferably on one side of the bag and are not parallel to eitheredges6 of the bag or to each other. Wires that are not parallel wires may also be in an “X” pattern or in other patterns. If the bag is to be sealed by twisting the top of the bag, as shown inFIG. 4, the wires are preferably onopposing sides2 and3 of the bag, are parallel toedges6 and to each other, and are equally spaced apart so that the same amount of bag material is in between them. In all the bags of this invention, the wires are not perpendicular to the sides of the bag. That is, the wires are either (1) diagonal to the sides or (2) they are parallel to the sides if they are on opposite sides.
For the pattern of conjoined diamonds shown inFIGS. 1 and 2, the wires intersect at least twice and preferably intersect about 3 to about 12 times. The wires preferably extend to within about 2 to about 4 inches ofedges6 in order to force most of the material of the bag into the desired shape when the bag is closed. Also, the crossing points of the wires are preferably about 1 to about 3 inches apart and preferably extend the same distance apart vertically as they do horizontally, so that the diamonds are squares. A pattern of intersecting wires may also use curved wires, where the two wires have sinusoidal shapes that are 180 degrees out of phase. For added strength and support, the wires are preferably bonded to each other at their crossing points. This may be accomplished by gluing, welding, soldering, melting the insulation on the wires, or other means.
InFIG. 3,re-sealable bag9 has twonon-parallel wires10 in a “/\” pattern that extend all the way from the bottom11 ofbag9 to top12. (A “\/” pattern may also be used but the “/\” pattern seals more easily.)Wires12 are fixed along their entire length to the inside ofbag9 by means oftape13.Bag9 is sealed by rolling up the top of the bag. Becausewires10 are not parallel, they do not form bulky coils when the top is rolled up and the wires cover a wider area of the bag.
InFIG. 4, re-sealableplastic bag14 is suitable for holding a product such as bread. Two opposingparallel wires15 and16 are fused directly into the plastic material ofbag14.Bag14 is sealed by twistingneck17 of the bag.
InFIGS. 5 and 6, re-sealableplastic bag18, holdingbagels19, has twonon-parallel wires20 and21 fused into the plastic material of the bag. It is sealed inFIG. 6 by twistingneck22.
Resealable bag1 may be made in a variety of ways. For example, for a paper bag the wires may be embedded within the paper when the paper is manufactured or they may be bonded to the paper at a later stage by gluing, adhesive, or tape. For plastic bags that are two ply, the wires may be placed in between the plies. The wires can also be made with a low temperature insulation on them that can be heat bonded to a plastic bag. Other manufacturing methods will also no doubt occur to those skilled in the art.
The bags may be used for containing various solid food items, such as potato chips, pretzels, cereal, bread, pet food, sugar, and flour, as well as non-food items, such as mortar mix, fertilizer, potting soil, salt, etc. Since the wires effectively seal the bags, the bags will not normally have any other types of seals on them other than the wires.
The following example further illustrates this invention:
EXAMPLE Two 24 gauge steel floral wires (Hillman) in various patterns were taped to the outside of plastic bags with 2 inch wide clear adhesive tape. A pattern of conjoined diamonds was made by hammering alternating rows of nails into a board, winding wires back and forth between the nails, and carefully removing the wires. The following table describes the various bags and patterns that were made and tested:
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| Bag | Number | | Pattern |
Sample | Size | ofbags | Pattern | Size | |
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1 | 8 × 14″ | 3 | Diamond | 1.5 × 14″ |
2 | 8 × 14″ | 2 | “/ \” | 6 × 14″ |
3 | 8 × 14″ | 2 | “\ /” | 6 × 14″ |
4 | 6 × 12″ | 3 | “X” | 3 × 12″ |
5 | 8 × 16″ | 3 | “/” “\”* | 4 × 16″ |
6 | 7 × 15″ | 4 | Parallel* |
7 | 8 × 14″ | 3 | Parallel |
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*wires placed on opposite sides of the bag.
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Bags Sealed by Rolling Up the Top
All of the bags maintained their shape and re-sealed after repeated openings and closings. The bags insamples 1 to 3 were filled with pretzels and the bags in sample 4 were filled with coffee. The bags were sealed by folding up the top, then they were unsealed and re-sealed again 30 times without the wires breaking or coming off the bag. The closed bags turned upside down, and shaken. The bags did not open and the contents of the bags did no come out of the bags despite the shaking.
Sample 1 and 2 bags were easily opened and closed with one hand, since the wires were placed closer together in the middle of the bags. However,sample 3, 4, and 7 bags required more effort to close, since the wires were widely spaced apart.
The bags insample 1 to 4 minimized the exposure of the contents of the bags to atmospheric air and eliminated the need for a clip or any other external closure device. Thesample 1 to 4 bags also decreased the rate at which food in the bags became stale in a humid environment.
The diamond pattern (sample 1 bags) was superior to all the other patterns as the diamond segments were easy to handle and fold. The diamond segments continually reinforced and complemented one another when the bags were closed and opened. This pattern produced the strongest seal in the center of the bag. The crossing wires of the bags insample 1 reinforced one another throughout repeated use, which helped the wires to maintain their opened and closed positions. The parallel wires (sample 7) must work independently. The crossing wires (samples 1 and 4) and the nonparallel wires (samples 2 and 3) increased the surface area of the bag that is directly controlled by the wires, which in turn provided a superior seal. The parallel wires (sample 7) acted directly on only a very small portion of the bag. The bags with crossed wires (sample 1) were easier to close than the bags with parallel wires (sample 7), and opened much easier because the wires reinforced one another at the center of the bag. The bags with crossed wires (sample 1) folded much more easily, and the diamond segments were easy to handle. The samples were rated based on the quality of the seal and the ease of closing in the order: 1>2>4>3>7.
Bags Sealed by Twisting
The bags insamples 5 and 6 were each filled with a loaf of bread, sealed by twisting, then unsealed, and re-sealed 20 times without the wires breaking or coming off the bags.Sample 5 and 6 bags provided an air-tight seal which completely secured the contents from the external environment. In another test, empty bags filled with air were closed tightly, and left sitting. After forty-eight hours, the bags remained sealed and inflated with air. The bags insamples 5 and 6 also reduced the rate at which food within the bags became stale, especially in humid environment.Sample 5 and 6 bags maintained a seal even when the bags were hung by their twisted necks. The bags insamples 5 and 6 can be sealed in one third the time it takes to seal a bag with an external tie.