FLEXIBLE STORAGE BAG WITH DUAL MECHANICAL CLOSURES
FIELD OF THE INVENTION
The present invention relates to sliding mechanical closures such as those commonly employed on flexible storage bags, particularly those suitable for use in the containment and protection of various items including perishable materials.
BACKGROUND OF THE INVENTION
Flexible storage bags for use in the containment and protection of various items, as well as the preservation of perishable materials such as food items, are well known in the art. Such bags typically comprise a rectangular sheet of polymeric film folded upon itself and sealed along two edges to form a semi-enclosed container having two flexible opposed sidewalls, three sealed or folded edges, and one open edge. A closure integrally formed with the bag such as an interlocking rib-type seal or separately provided such as a plastic or paper-clad-wire tie completes the containment assembly.
As utilized herein, the term "flexible" is utilized to refer to materials which are capable of being flexed or bent, especially repeatedly, such that they are pliant and yieldable in response to externally applied forces. Accordingly, "flexible" is substantially opposite in meaning to the terms inflexible, rigid, or unyielding. Materials and structures which are flexible, therefore, may be altered in shape and structure to accommodate external forces and to conform to the shape of objects brought into contact with them without losing their integrity. Flexible storage bags of the foregoing variety are typically formed from polymeric film, such as polyethylene or other members of the polyolefin family, in thicknesses of between about 0.0002 inches to about 0.002 inches. Such films are frequently transparent but sometimes are opaque and/or colored.
Flexible storage bags of the currently commercially available variety provide a means of conveniently storing a wide range of objects and materials in a generally disposable containment device. Flexible storage bags with sliding mechanical closures have been developed to improve the ease of opening and closing mechanical interlocking seals. While such sliding mechanical closures have proven suitable for such uses, there remains the issue of determining whether the slider mechanism has in fact been completely translated across the mouth of the bag to achieve the desired completion of the closing operation. The same questions can arise with regard to mechanical interlocking closures which rely upon manually pressing interlocking elements together without a slider mechanism.
Accordingly, it would be desirable to provide a flexible storage bag which provides for a positive indication of when a complete closure has been achieved and increased security against accidental opening.
SUMMARY OF THE INVENTION
The present invention provides a flexible storage bag having an opening and at least two mechanical closures for closing the opening. The mechanical closures preferably comprise mechanical interlocking seals, and at least one closure preferably includes a slider for closing the mechanical closure.
BRIEF DESCRIPTION OF THE DRAWINGS
While the specification concludes with claims particularly pointing out and distinctly claiming the present invention, it is believed that the present invention will be better understood from the following description in conjunction with the accompanying Drawing Figures, in which like reference numerals identify like elements, and wherein:
Figure 1 is an elevational view of a flexible storage bag employing dual mechanical closures in accordance with the present invention in an open, empty condition; and
Figure 2 is an elevational view of the flexible storage bag of Figure 1 in a fully closed condition.
DETAILED DESCRIPTION OF THE INVENTION
Figure 1 depicts a presently preferred embodiment of a flexible storage bag 10 according to the present invention. In the embodiment depicted in Figure 1, the flexible storage bag 10 includes a bag body 20 formed from a piece of flexible sheet material folded upon itself along fold line 22 and bonded to itself along side seams 24 and 26 to form a semi-enclosed container having an opening along edge 30. Flexible storage bag 10 also includes mechanical closures 40 and 50 located adjacent to edge 30 for sealing edge 30 to form a fully-enclosed container or vessel as shown in Figure 2. Bags such as the flexible storage bag 10 of Figure 1 can be also constructed from a continuous tube of sheet material, thereby eliminating side seams 24 and 26 and substituting a bottom seam for fold line 22.
As shown in Figure 1, the mechanical closure 40 includes an interlocking mechanical seal of any suitable conventional design. The mechanical closure 50 also includes a slider 60 of suitable conventional design for the type of interlocking mechanical seal employed in mechanical closure 50. The combination of the dual mechanical closures provides a positive indication that a fully completed closure operation has been achieved after the consumer has performed two closure sequences. The consumer therefore has confidence that even if one or
the other of the mechanical closures should fail or be incompletely secured, the other closure will provide the desired protection of the contents. A plurality of mechanical closures, two, three, or more may be employed, and appropriate types of closures may be selected. For ease of operation, in most instances the closure at the edge 30 may employ a slider while the other closure(s) farther down the faces of the bag typically will not utilize a slider mechanism.
Various compositions suitable for constructing the flexible storage bags of the present invention include substantially impermeable materials such as polyvinyl chloride (PVC), polyvinylidene chloride (PVDC), polyethylene (PE), polypropylene (PP), aluminum foil, coated (waxed, etc.) and uncoated paper, coated nonwovens etc., and substantially permeable materials such as scrims, meshes, wovens, nonwovens, or perforated or porous films, whether predominantly two-dimensional in nature or formed into three-dimensional structures. Such materials may comprise a single composition or layer or may be a composite structure of multiple materials, including a substrate material utilized as a carrier for a substance.
Once the desired sheet materials are manufactured in any desirable and suitable manner, comprising all or part of the materials to be utilized for the bag body, the bag may be constructed in any known and suitable fashion such as those known in the art for making such bags in commercially available form. Heat or adhesive sealing technologies may be utilized to join various components or elements of the bag to themselves or to each other. In addition, the bag bodies may be thermoformed, blown, or otherwise molded rather than reliance upon folding and bonding techniques to construct the bag bodies from a web or sheet of material. Two recent U.S. Patents which are illustrative of the state of the art with regard to flexible storage bags similar in overall structure to those depicted in Figures 1 and 2 but of the types currently available are Nos. 5,554,093, issued September 10, 1996 to Porchia et al., and 5,575,747, issued November 19, 1996 to Dais et al.
While particular embodiments of the present invention have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. It is therefore intended to cover in the appended claims all such changes and modifications that are within the scope of this invention.