Title of Invention

A PRESS TYPE RE-CLOSABLE FLEXIBLE PACKAGE

Abstract

The invention relates to a press type re-closable flexible package with a zipper attached to the two sides forming the mouth of the package; said zipper having inter locking elements on the two sides wherein the two sides of the zipper extend beyond the interlocking elements to form flaps for easy gripping characterized in that one flap is longer than the other to provide for an easy grip of the package.

Full Text

The invention relates to a press type re-closable flexible package. BACKGROUND OF THE INVENTION Re-closable packages, bags or pouches have found wide spread use for a number of industries. Such bags are used for packing food, medicines, cosmetics, buttons, labels, cigarettes, pens, stationary etc. Re-closable packages may be broadly classified into the following two categories: Re-closable package having slider and a zipper to open and close the package Re-closable package having interlocking elements that are pressed together to seal the package, referred to as 'press type' packages. The first category of a re-closable package usually consists of a bag or a pouch with an open end forming the mouth, with a zipper having interlocking elements attached to the mouth. A slider is mounted on this zipper to open and close the bag. Two separate processes make the bag and the zipper and they are then joined together by any known joining process. Slider zipper bags are available in large varieties including bags with barriers, barriers with score lines etc. The applicant's co-pending applications 1159/MUM/2002 and 718/MUM/2003 describe such packages. The second category of re-closable packages comprises of a bag having an open mouth where the two sides of the mouth of the bag are also provided with a zipper that has interlocking members that lock with each other when the two sides of the mouth are pressed against each other. The bags are therefore referred to as 'press type' re-closable bags or packages. Press type packages are also available in large variety and sizes and may be made in a single process where the material used for making the bag is the same as the material used in forming the zipper and the interlocking elements on the zipper. This imposes a limitation on the materials that may be used for the inter-locking elements and the bag. Typically only a monolayer package is possible with this process resulting in limited barrier properties. Press type re-closable packages are cheaper and easier to manufacture than the slider zipper packages, primarily on account of the absence of the slider and the related inventory costs. However, the press type packages suffer from inherent disadvantages such as the two sides of the mouth may not seal entirely along the opening or tendency of the package to open during handling or transporting. Press type packages also do not offer barrier properties to the contents of the package and thus their application in the industry is limited, in spite of their cost advantages. Another disadvantages of press type packages is that in order to open the package, the two sides of the mouth have to be held and pulled apart. As the two sides of the mouth tend to stick to each other the user is often found struggling to get a good grip on the two sides of the mouth in order to pull them apart. In the case of Press type packages the user tends to apply excessive pressure against the interlocking elements in order to seal the package. This eventually results in the wear of the interlocking members thereby reducing the effective life of the package. The interlocking members also tend to wear out on account of mis-alignment of the interlocking members on the two sides of the zipper. Lastly, it is also desirable that press type packages provide some form of tamper proof means that indicates that the package has been tampered with or opened before. Such tamper indicating means may be in the form of a peel seal or a barrier. It is further required that a press type package offer strong barrier properties to the contents of the package especially during handling and transporting. Various examples of press type bags with different kinds of tamper indicating mechanism are available in the prior art for example, US Patent 4966470 to Thompson. Thompson discloses a zipper with interlocking elements and a peal seal that acts as a tamper indicating mechanism. US 4672723 to Hugues also discloses another example of a zipper comprising of interlocking elements. The document discloses a projection on one side of the zipper that locks with a corresponding slot on the other side of the zipper to provide a re-closable package. Another example of a zipper with interlocking elements may be found in US 52383086 to Heintz. The document also discloses a tamper evident feature in the form of a peal seal. US Patents 61320869, 6082897, 6234676 and 6231235, all granted to Galomb disclose an alternate system of interlocking elements in which the interlocking elements of the zipper also seal the material of the bag between them to provide and air tight re-closable package. The efficiency however, of such an arrangement is open to debate. The tamper evident feature in the form of a peal seal suffers from the draw back of not being 100% reliable and also does not provide adequate barrier properties. To overcome the draw back of misalignment of the interlocking elements of the zipper, US 6004032 to Kapperman discloses a pair of interlocking elements with aligning members between them. The closure arrangement as described by Kapperman provides a firm leak proof re-closable mechanism that also provides for ease in aligning the interlocking elements. However, none of the existing press type packages adequately address or overcome all the limitations of such packages. Thus while some packages provide a better interlocking system they suffer from weak barrier and tamper proof properties and vice-versa. Furthermore, none of the existing packages concentrate on the difficulty in gripping and opening press type packages. There is therefore a requirement for a flexible re-closable press type bag that offers better gripping, improved barrier properties, better alignment of the inter-locking members providing a better seal and also a longer life for repeated use. OBJECTS AND SUMMARY OF THE INVENTION It is an object of the invention to provide a press type re-closable flexible package that is easy to grip, has strong barrier properties, offers better alignment of the inter-locking members and has a longer life. It is an object of the invention to provide a press type re-closable package that has a clear tamper indicating mechanism. It is an object of the invention to provide a press type re-closable flexible package that is easy to use and open offers a perfect seal across the mouth of the package. It is an object of the invention to provide a tamper proof press type re-closable flexible package that is economical and easy to manufacture. To meet the aforementioned objectives, the invention provides for a press type re-closable flexible package with a zipper attached to the two sides forming the mouth of the package; said zipper having inter locking elements on the two sides wherein the two sides of the zipper extend beyond the interlocking elements to form flaps for easy gripping characterized in that one flap is longer than the other to provide for an easy grip of the package BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS The accompanying drawings illustrate the preferred embodiments of the invention and together with the following detailed description serve to explain the principles of the invention. Figure 1 illustrates a press type re-closable flexible package in accordance with the invention. Figure 2 illustrates an embodiment of the invention including a tamper proof barrier. Figure 3 illustrates a side perspective view of the zipper for a press type package in accordance with the invention. Figure 4 illustrates an embodiment of the flexible package with three sides sealed. Figure 5 illustrates another embodiment of the flexible package with gussets on three sides of the package. Figure 6 illustrates another embodiment of the invention wherein the flexible package is provided with a handle. DETAILED DESCRIPTION OF THE INVENTION For the purpose of promoting an understanding of the principles of the invention, reference will now be made to the embodiment illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood diat no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated device, and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates. The invention provides for a novel re-closable flexible press type package wherein at the mouth of the bag is provided two sides of the zipper. Figures 1 illustrates the gripping, inter- locking and aligning elements of the zipper in accordance with the invention. The zipper is made of a stronger polymeric material than the pouch of bag and comprises of two sides (2, 3). The sides of the zipper extend beyond the inter-locking elements to form flaps (14,15) for easy gripping. One side of the zipper is longer than the other side such that on sealing the bag the two flaps (14, 15) at the end of the zipper can be easily separated from each other. The difference in lengths of the flaps ensures that the user can grip the edges of both flaps without rubbing the flaps together, as is required with existing packages, to separate them. The ability to easily open the package is significant in improving the overall customer convenience and experience. To further facilitate the gripping of the flap, the flaps (14, 15) are also provided with ribs (5, 6) on their inner surface to provide better gripping of the flaps for pulling open the zipper. The ribs provide a rough surface for a firmer grip and are especially useful in cases where the user's hands are wet. It is to be noted here that though in the figure the side 3 has been shown longer than side 2, it is within the scope of the invention to have either one of the flap longer in length than the other. Similarly, it has been shown in the figure that the side 2 of the zipper has two ribs for gripping whereas the side 3 has a single rib, it is within the scope of the invention to have multiple such ribs on both or one of the two sides of the zipper. The two sides of the zipper are also provided with interlocking elements. The sides are also provided with aligning members (7, 8, 13) that ensure that the interlocking elements correctly mate with each other and also do not open easily during handling and transportation. As shown in figure 1, side (2) of the zipper is provided with two interlocking elements (9,10) with a first aligning element (8) between them. The upper interlocking element (9) faces downwards whereas the lower interlocking element (10) faces upwards. The second side (3) of the zipper is also provided with two interlocking elements (11, 12) in between a second and third aligning elements (7 and 13). The upper interlocking element (11) faces upwards to lock with the corresponding interlocking element (9) facing downwards on the opposite side of the zipper. Similarly, the lower interlocking element (12) faces downwards to lock with the corresponding interlocking element (10) that faces upwards. However, it should be noted that the direction of the interlocking elements may change on the two sides of the zipper such that a joint is formed. For example, the upper interlocking element (9) on the first side of the zipper may face upwards with the corresponding interlocking element of the second side (11) facing downwards. Similarly, the lower interlocking element (10) of the first side may face downwards with the corresponding interlocking element (12) on the second side of the zipper facing upwards. The aligning member (7) seals the interlocking elements from the outside once the mouth of the bag is sealed whereas the aligning member (13) covers the interlocking members from below. The intermediate aligning member (8) separates the two pairs of interlocking elements and also in conjunction with aligning members (7, 13) serves to press the inter locking elements against each other. Such a system of the interlocking elements and the aligning members provides for an improved seal across the mouth of the bag that does not open easily during handling and transporting and also provides improved barrier properties to the contents of the package, as shown in figure 3. In accordance with another aspect of the invention, in order to make the bag tamper proof and also to provide improved barrier properties, the invention provides for a diaphragm (18) of a metallized laminate that is sealed across the sides 2 and 3 of the zipper. The flexible package (1) with such a metallized laminate is illustrated in figure 2. The metallized laminate (18) provides better barrier properties than a diaphragm of the same material as the zipper provides, as is the case for existing packages. Thus though it would be simpler to manufacture the zipper with the lower end sealed together to form a diaphragm, a diaphragm so formed would be permeable to certain gases such as nitrogen and also would be susceptible to moisture and other contaminants. The invention therefore provides for a metallized laminate that is known to have excellent barrier properties. In the preferred embodiment the metallized laminate structure used in the manufacture of the package may also be used to form the metallized laminate. The metallized laminate in the form of a barrier diaphragm can also be printed upon. This would further serve as a means of tamper indicating as well as improve the package appeal. In accordance with another aspect of the invention in order to facilitate easy opening of the package for the first time, that is to tear upon the diaphragm to access the content to the package, the metalli2ed laminate has a score line. The score line may be provided by a laser that penetrates only up to the metallized layer of the diaphragm but not through the entire thickness of the diaphragm. Such a score line helps the user of the package to tear upon a barrier without compromising the barrier properties of the metallized laminate. As shown in figure 2, the barrier diaphragm (18) in the form of a metallized laminate may be sealed to the two sides of the zipper. The assembly of the zipper and diaphragm is sealed to one end (16) of the flexible package (1). The flexible package comprises of two sides (16,17) that may be sealed along the three edges or may have gussets. The flexible package as shown in figure 2, has one side (17) of the package open. Such a package can be used by manufacturers of various commodities for filling through the open side (20). After filling the package the manufacturer needs to perform a simple heat seal operation between the side (17) and the diaphragm to provide an air tight package. This signiflcandy eliminates the investment required at the manufacturers premises of cosdy packaging machines, such as the form fill seal machines. In further embodiments the package may be three side sealed, three side gusseted or stand up pouch as per the requirements. The package may also be provided with a handle in an embodiment of the invention. Figure 4 illustrates a package (30) that is sealed on three sides and has a mouth (32) on the fourth side. The mouth is provided with the zipper and the diaphragm in accordance with the invention. Figure 5 illustrates an embodiment of the re-closable package (40) provided with gussets on three sides. The package has side gussets (42) and a bottom gusset (44). A gusset is additional material provided at the edges of the package to increase the volume of the package. The mouth (46) of the package is provided with the zipper in accordance with the invention. In another embodiment as shown in Figure 6, the flexible package (50) may be provided with handle (54) at the mouth (52) to facilitate the lifting of the package. In the figure the package is shown to have gussets on the three sides, however, the handles may be provided to a package with no gussets, two side gussets, or a stand up pouch. While the invention has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only the preferred embodiment has been shown and described and that all changes and modifications that come within the scope of the invention are desired to be protected. I Claim: 1. A press type re-closable flexible package comprising a zipper attached to the two sides (2,3) forming the mouth of the package; said zipper having inter locking elements (9,10) on the two sides wherein the two sides of the zipper extend beyond the interlocking elements to form flaps (14,15) for easy gripping characterized in that one flap is longer than the other to provide for an easy grip of the package. 2. A press type re-closable flexible package as claimed in claim 1 wherein the flaps are provided with ribs on their inner surfaces to provide a firmer grip on the package. 3. A press type re-closable flexible package as claimed in claim 1 wherein a diaphragm of a metallized laminate is sealed across the two sides of the zipper to provide a tamper indicating barrier. 4. A press type re-closable flexible package as claimed in claim 3 wherein the diaphragm is provided with a score line that penetrates up to the metallized layer. 5. A press type re-closable flexible package as claimed in claim 1 wherein the zipper comprises: a first pair of inter-locking elements on the first side of the zipper; - a second pair of inter-locking elements on the second side of the zipper; a first alignment element between the first pair of inter-locking elements; a second alignment element above the second pair of interlocking elements and a third alignment element below the second pair of interlocking elements. 6. A press type re-closable flexible package as claimed in claim 1 wherein the package is sealed on three sides. 7. A press type re-closable flexible package as claimed in claim 1 wherein the package has gussets on three sides to increase the volume of the package. 8. A press type re-closable flexible package as claimed in claim 1 wherein the package is a stand up pouch.

Documents:

1791-del-2005-abstract-01-05-2008.pdf

1791-del-2005-abstract.pdf

1791-DEL-2005-Claims-(26-03-2008).pdf

1791-del-2005-claims-01-05-2008.pdf

1791-del-2005-claims.pdf

1791-DEL-2005-Correspondence-other-(26-03-2008).pdf

1791-del-2005-correspondence-others-01-05-2008.pdf

1791-del-2005-correspondence-others.pdf

1791-del-2005-description (complete).pdf

1791-DEL-2005-Drawings-(26-03-2008).pdf

1791-del-2005-drawings.pdf

1791-del-2005-form-1.pdf

1791-del-2005-form-18.pdf

1791-DEL-2005-Form-2-(26-03-2008).pdf

1791-del-2005-form-2.pdf

1791-del-2005-form-3.pdf

1791-del-2005-form-9.pdf

1791-del-2005-gpa.pdf