WO2000071433A1

WO2000071433A1 - Reclosable storage bag with color closure indicator

Info

Publication number: WO2000071433A1
Application number: PCT/US2000/013850
Authority: WO
Inventors: Daniel Raymond Cerone; Catherine Jean Randall
Original assignee: The Procter & Gamble Company
Priority date: 1999-05-21
Filing date: 2000-05-19
Publication date: 2000-11-30
Also published as: CN1351567A; KR20020001890A; MXPA01011928A; CA2373261A1; BR0010780A; AU5441900A; JP2003500298A; TW462938B; EP1181206A1

Abstract

The present invention provides a flexible storage bag (10) having an opening and a closure system (40) for the opening, wherein the closure system provides a high contrast color indication when complete closure of the closure system has been achieved. The closure system may be a mechanical interlocking seal or an adhesive-based closure system. The high contrast color indication may be a change from coloress to colored, from white to black, and/or from translucent to opaque.

Description

RECLOSABLE STORAGE BAG WITH COLOR CLOSURE INDICATOR

FIELD OF THE INVENTION

The present invention relates to closures such as those commonly employed on flexible storage bags, particularly those suitable for use in the containment and protection of vaπous items including perishable mateπals.

BACKGROUND OF THE INVENTION

Flexible storage bags for use in the containment and protection of vaπous items, as well as the preservation of peπshable mateπals such as food items, are well known in the art. Such bags typically compπse a rectangular sheet of polymeπc 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 πb-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 mateπals which are capable of being flexed or bent, especially repeatedly, such that they are pliant and yieldable m response to externally applied forces. Accordingly, "flexible" is substantially opposite in meaning to the terms inflexible, πgid, or unyielding. Mateπals 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 vanety are typically formed from polymeπc 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 vanety provide a means of conveniently stoπng a wide range of objects and matenals in a generally disposable containment device Many commercially available flexible storage bags utilize mechanical interlocking seals to achieve closure of the bag opening, and some such bags additionally employ a sliding mechanical closure to improve the ease of opening and closing mechanical interlocking seals. With either type of mechanical interlocking seal, there remains the issue of determining whether complete closure has in fact been completed across the mouth of the bag to achieve the desired completion of the closing operation. Currently there are two color change systems on the market for such closures. One system involves the interlocking of blue and yellow elements to produce a green seal, while the other involves the interlocking of red and blue elements to produce a purple seal. These are accomplished by simply dying each side of the translucent zipper closure a different primary color so that when they are pressed together to seal, light passing through the closure produces an apparent color which is the secondary color formed from the ongmal two pπmary colors. While such systems do provide a color change indication of when sealing has been accomplished, under many lighting conditions it is difficult to discern whether the color seen by the consumer is produced by interlocking of the seals or by light passing through elements which are merely closely superimposed. Moreover, those individuals with visual impairments such as color blindness or reduced visual acuity may not correctly interpret the condition of the seal by vision alone

Accordingly, it would be desirable to provide a closure which provides for a positive indication of when a complete closure has been achieved.

SUMMARY OF THE INVENTION

The present invention provides a flexible storage bag having an opening and a closure system for the opening, wherein the closure system provides a high contrast color indication when complete closure of the closure system has been achieved. The closure system may be a mechanical interlocking seal or an adhesive-based closure system. The high contrast color indication may be a change from colorless to colored, from white to black, and/or from translucent to opaque.

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 mvention will be better understood from the following descπption 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 a closure m accordance with the present invention;

Figure 2 is an elevational view of another flexible storage bag in accordance with the present mvention;

Figure 3 is a perspective view of a further flexible storage bag m accordance with the present invention; and Figure 4 is an elevational view of yet another flexible storage bag in accordance with the present invention. 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 mateπal 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 a mechamcal closure system 40 located adjacent to edge 30 for sealing edge 30 to form a fully-enclosed container or vessel. Bags such as the flexible storage bag 10 of Figure 1 can be also constructed from a continuous tube of sheet mateπal, thereby eliminating side seams 24 and 26 and substituting a bottom seam for fold line 22. The mechanical closure system 40 includes an interlocking mechanical seal of any suitable conventional design.

In accordance with the present invention the closure system 40 provides a high contrast color indication when complete closure of the closure system has been achieved. As utilized herein, the term "high contrast color indication" is used to refer to refer to a change in visual appearance that is categoπcal rather than a matter of degree. For example, the high contrast color indication may be a change from colorless to colored, from white to black, and/or from translucent to opaque, rather than a change from one color to another of the same degree The high contrast color indication may be visible from one or both sides of the bag. With continued reference to Figure 1, the closure system 40 provides a high contrast color indication in the form of a change from the initial clear/transparent/colorless appearance indicated by the numeral 60 to the purple color appearance indicated 'ι the numeral 50 when the hand 70 of the consumer is translated along the closure system 40 to interlock the opposing elements of the mechanical interlocking seal. Figure 2 illustrates a similar flexible storage bag 10 wherein the high contrast color indication is in the form of a change from the initial white appearance indicated by the numeral 60 to the black color appearance indicated by the numeral 50.

Figure 3 illustrates a flexible storage bag 10 which utilizes a pressure-activated adhesive- based closure system 45 which provides a high contrast color indication in the form of a change from the initial clear/transparent/colorless appearance indicated by the numeral 60 to the green color appearance indicated by the numeral 50. A suitable adhesive-based closure system comprises a selectively activatible adhesive-beaπng structure protected from inadvertent contact by a plurality of compressible, collapsible protrusions surrounded by adhesive which provides a secure closure seal upon activation. Suitable representative three-dimensional mateπals of this vanety which include a thin layer of pressure-sensitive adhesive protected from inadvertent contact, as well as methods and apparatus for manufactuπng them, have been developed and are described in detail in commonly-assigned U.S. Patent Nos. 5,662,758, issued September 2, 1997 to Hamilton and McGuire, entitled "Composite Matenal Releasably Sealable to a Target Surface When Pressed Thereagamst and Method of Making", and 5,871,607, issued February 16, 1999 to Hamilton and McGuire, entitled "Mateπal Having A Substance Protected by Deformable Standoffs and Method of Making", and commonly-assigned, co-pending U.S. Patent Application Nos. 08/745,339 (allowed), filed November 8, 1996 in the names of McGuire, Tweddell, and Hamilton, entitled "Three-Dimensional, Nestmg-Resistant Sheet Matenals and Method and Apparatus for Making Same", 08/745,340, filed November 8, 1996 in the names of Hamilton and McGuire, entitled "Improved Storage Wrap Matenals", all of which are hereby incorporated herein by reference.

Figure 4 is a flexible storage bag 10 similar to that of Figure 1, but employing a sliding mechanical closure (not numbered) as a mechanism for closing the interlocking mechanical closure 40. The sliding mechanical closure may be of suitable conventional design for the type of interlocking mechanical seal employed. Any suitable means for generating the high contrast color indication consistent with the matenals utilized for bag and closure system construction, the intended contents of the bag (i.e., food grade, stenle, etc.), and the environmental conditions foreseen may be utilized. Colors and indications can be selected depending upon the color of the bag components, bag contents, and chemical/structural approaches utilized. For example, the high contrast color indication from translucent to opaque or black can be accomplished through opposing surfaces having coatings that when pressed together blocked enough light to appear much darker when together. Another more exotic approach would be to use coatings that polaπzed light so that when they were separate they appeared completely clear but when together would block sufficient light transmission to make them appear opaque. Another suitable approach to generating a high contrast color indication would be to use a system of chemicals that when contacted created a color via chemical reaction One such system would include a microencapsulated phenolthalene solution sprayed on one side of a seal and a microencapsulated basic solution sprayed on the other. When the two sides were pressed together under sufficient pressure to make a seal the capsules would break, the indicators would react, and a pmk color would be apparent. Potentially this could be done without the microcapsules if adequate water could be entrained in an adhesive.

Another approach would be to use encapsulated ink similar to that utilized for carbonless forms. These could be pnnted within the texture of the adhesive closure sytem opposite the adhesive and covered with a varnish or other impervious coating, or potentially between the adhesive and the bag mateπal. For mechanical closure systems, the encapsulated ink could be located withm the mechanical interlocking seal. Vaπous compositions suitable for constructing the flexible storage bags of the present invention include substantially impermeable mateπals such as polyvmyl chloπde (PVC), polyvmyhdene chloride (PVDC), polyethylene (PE), polypropylene (PP), aluminum foil, coated (waxed, etc.) and uncoated paper, coated nonwovens etc., and substantially permeable materials such as scnms, meshes, wovens, nonwovens, or perforated or porous films, whether predominantly two-dimensional in nature or formed into three-dimensional structures Such materials may compnse a single composition or layer or may be a composite structure of multiple mateπals, including a substrate mateπal utilized as a earner for a substance.

Once the desired sheet mateπals are manufactured in any desirable and suitable manner, compnsing all or part of the mateπals 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 mateπal. 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

While particular embodiments of the present invention have been illustrated and descnbed, it would be obvious to those skilled in the art that vaπous other changes and modifications can be made without departing from the spmt and scope of the invention. It is therefore intended to cover m the appended claims all such changes and modifications that are withm the scope of this mvention.

Claims

WHAT IS CLAIMED IS:

1. A flexible storage bag comprising:

(a) a bag having an opening; and

(b) a closure system adjacent said opening for closing said opening; wherein said closure system provides a high contrast color indication when complete closure of said closure system has been achieved.

2. The flexible storage bag of Claim 1, wherein said high contrast color indication is progressive with regard to the degree to which said closure has been closed.

3. The flexible storage bag of Claim 1 , wherein said closure is a mechanical interlocking seal.

4. The flexible storage bag of Claim 3, wherein said closure further includes a sliding mechanical closure.

5. The flexible storage bag of Claim 1, wherein said closure compπses an adhesive-based closure system.

6. The flexible storage bag of Claim 1, wherein said high contrast color indication is selected from the group consisting of clear to colored, white to black, translucent to opaque, and combinations thereof.

7. The flexible storage bag of Claim 1, wherein said high contrast color indication is accomplished via chemical reaction.

8. The flexible storage bag of Claim 1, wherein said high contrast color indication is accomplished via polaπzation of light.

9. The flexible storage bag of Claim 1, wherein said high contrast color indication is accomplished via encapsulated ink.

10. The flexible storage bag of Claim 1, wherein said high contrast color indication is accomplished via coatings on opposed surfaces.