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(11) | EP 1 009 672 B1 |
| (12) | EUROPEAN PATENT SPECIFICATION |
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| (54) |
METHOD FOR MAKING A TAMPER-EVIDENT CONTAINER WITH RECLOSABLE FASTENER HERSTELLUNGSVERFAHREN FÜR EINEN ORIGINALITÄTSGESICHERTEN BEHÄLTER MIT WIEDERVERSCHLIESSBARER VERRIEGELUNGSVORRICHTUNG PROCEDE POUR PRODUIRE UN CONTENANT INDICATEUR D'EFFRACTION, DOTE D'UN SYSTEME D'ATTACHE POUVANT SE REFERMER |
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| Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention). |
Field of the Invention.
[0001] The present invention relates to an improved method for attaching a reclosable zipper fastener to a flexible material from which a container is made. Access to the interior of such a container is provided by a security seal formed through the flexible material, and the reclosable fastener in the method of this invention is attached to the container in sealing relation to that seal. The improved fastener in the method of this invention is characterized by its structure comprising a pair of mating, reclosable sealing strips, both of which are attached to a common surface of the container's flexible material. Preferably, the reclosable fastener in the method of this invention is disposed on the inside surface of the container.
Description of the Prior Art.
[0002] Reclosable containers utilizing zipper-type fasteners are well known in the packaging industry and are used for holding, displaying and dispensing a wide variety of products ranging from hardware items to food products intended for human consumption. The construction of virtually all such prior art fasteners comprises one or more female parts which releasably receive one or more corresponding male parts. In order to provide access to the interior of the container, those portions of the fastener bearing the respective female and male parts must typically be attached to opposing sides of the container such that the female and male parts will be in registry with each other. A typical such construction is disclosed in U. S. Patent No. 4,909,017 to McMahon and Spanier.
[0003] US 5,024,537 discloses a fastener strip attached to a flexible material forming a container, which fastener strip extends to the side edges of the bag. However, when sealing the side edges of this arrangement, the differences in thickness between the fastener and the spot sealed ends of the fastener results in holes or gaps forming in the side seals.
[0004] US 5,461,845 also discloses a fastener strip segment attached to a flexible material forming a container by heat conventional sealing means.
[0005] Obviously, then, according to the present state of the packaging arts, great care and precision are required in the placement and attachment of reclosable fasteners to their related containers. Notwithstanding the existence of a great variety of such fasteners and reclosable containers utilizing such fasteners, it is clear that there remains a great need in the packaging arts for a reclosable, zipper-type fastener, both parts of which can be attached to a single common surface of the material forming a wall of the container before the container is even partially formed. Such a fastener would significantly simplify the manufacturing process for reclosable containers by not interfering with the operation of standard forming and filling machines.
SUMMARY OF THE INVENTION
[0006] The present invention relates to an improved method according to claim 1 for producing a tamper-evident container formed from a flexible material and having a reclosable fastener. In a preferred embodiment, the fastener comprises a pair of mating, reclosable sealing strips, each comprising a strip base segment which is attachable to a common surface of the material forming a wall of a reclosable container. Each of the sealing strips further comprise a second segment integral with its corresponding base segment and free from the container wall surface. One of the strips comprises a male fastener part, and the other of the strips comprises a female fastener part in receiving relation to the male part. Tamper-evident access to the interior of the container is provided by a removable portion of the flexible material to form an aperture for access to the reclosable fastener.
[0007] According to a first embodiment of the reclosable fastener, the male fastener part is at the juncture of one of the base segments and its corresponding second segment, and the female fastener part is formed on the second segment of the other sealing strip. Both base segments are attached to a common interior surface of the flexible material, and both second segments are free from the common surface.
[0008] According to a second embodiment, the female fastener part is formed on one of the sealing strip second segments, and that second segment is attached to a second surface of the flexible material opposite the common surface.
[0009] Hereinafter is disclosed and claimed a method for attaching the reclosable zipper-type fastener to the flexible material from which the container is made so as to provide a tamper-evident reclosable seal.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] For a fuller understanding of the nature and objects of the invention, reference should be had to the following detailed description taken in connection with the accompanying drawings, in which:
FIGURE 1 is a side elevation showing a segment of a first embodiment of the container of this invention with the fastener attached to the inside of a segment of the flexible material at least partially forming a reclosable container.
FIGURE 2 is a side elevation similar to that of Fig. 1 showing the segment of the reclosable container with the tamper-evident portion removed and the fastener opened.
FIGURE 3 is a view similar to that of Fig. 1 showing a second embodiment of the container.
FIGURE 4 is a side elevation similar to that of Fig. 3 showing the segment of the reclosable container with the tamper-evident portion removed and the fastener opened.
FIGURE 5 is a sectional view taken along line 5-5 of Fig. 6 showing attachment of the reclosable fastener to a common interior surface of a reclosable container.
FIGURE 6 is a plan view of the reclosable container shown in Fig. 5.
[0012] Similar reference characters refer to similar parts throughout the several views of the drawings.
DETAILED DESCRIPTION
[0013] A first embodiment of the improved tamper-evident container formed from a flexible material and having a reclosable fastener is generally indicated as 10 in the views of Figs. 1, 2, 5 and 6. The reclosable fastener is generally indicated as 12.
[0014] Referring to the view of Fig. 1, it can be seen that fastener 12 comprises a pair of mating, reclosable sealing strips, generally indicated as 14 and 16, respectively. Each of the sealing strips 14 and 16 comprise a base segment 18 and 20, respectively. Base segment 18 is attached to interior surface 22 of flexible material 24, and base segment 20 is similarly attached to the common interior surface 22. As shown in Fig. 1, attachment of the fastener 12 to common interior surface 22 is indicated by perimeter seal 26.
[0015] Also shown in the view of Fig. 1 is a removable portion 28 of flexible material 24 by which access to the interior of container 10 may be obtained once portion 28 is removed to form an aperture providing access to strips 14 and 16 whereby they may be separated from each other. This is clearly illustrated in the "opened" view of Fig. 2. Referring to the view of Fig. 6, it can be seen that removable portion 28 is defined by a plurality of cuts formed through flexible material 24. In the preferred embodiment, these cuts comprise a plurality of perforations 30 and at least one slit 32, though a pair of opposed slits 32 are illustrated in the view of Fig. 6. Slit 32 provides a free segment of flexible material 24 whereby portion 28 may be removed to provide access to fastener 12. The perforations 30 are preferably formed within the area defined by line A-A, and the slit, or slits, 32 are preferably formed within the area between arrows B.
[0016] Returning to the view of Fig. 1, sealing strip 14 further comprises a second segment 34 integrally formed therewith, but not attached to common interior surface 22. Sealing strip 16 also comprises a second segment 36 integral with its base segment 20, but not attached to common interior surface 22. A female fastener part 38 is formed on second segment 34, and a corresponding male fastener part 40 is formed on sealing strip 16 at the juncture of base segment 20 with second segment 36.
[0017] As further shown in the view of Fig. 1, container 10 further includes another segment of flexible material 24' forming another wall thereof, and a seam 42 is provided by the joining of flexible material 24 to a corresponding segment of flexible material 24'. Referring to the views of Figs. 5 and 6, a similar seam 42' is formed at the bottom of container 10.
[0018] Referring to the view of Fig. 6, and remembering that a principal end use for the container 10 is to hold food products intended for human consumption, the formation of an hermetic seal is a particular advantage of this invention. As shown in Fig. 6, the perimeter seal 26 extends around the perimeter of fastener 12. However, a broadened segment 44 can be seen at each end of perimeter seal 26. Broadened segment 44 is frequently referred to in the packaging industry as a "splotch" seal. Such a splotch seal involves the application of heat and pressure to the distal ends of sealing strips 14 and 16 so as to form a flattened, broadened segment 44. Then, when the fastener 12 is attached to common interior surface 22 of flexible material 24 by the perimeter seal 26, an hermetic seal is formed in completely surrounding relation to the removable portion 28.
[0019] Referring now to the views of Figs. 3 and 4, a second embodiment of the tamper-evident container is generally indicated as 10'. Inasmuch as the structural elements of container 10' are essentially identical to those of first embodiment 10, identical reference numerals have been used for their identification. As clearly shown in the views of Figs. 3 and 4, second embodiment 10' further comprises a tack seal 46 to bond second segment 34 to inside surface 48 of flexible material 24' forming the opposite side of container 10'. Such a construction virtually eliminates any probability of material contained within container 10' becoming wedged or caught in the gap otherwise present between second segment 34 and flexible material 24'.
[0020] From the above description of the structure of first and second embodiments of the container 10 and 10', respectively, attention is now invited to the following description of the method for attaching fastener 12 to a flexible material 24 for providing a tamper-evident reclosable opening therethrough. First, a segment of flexible material 24 is selected for forming a container 10. A plurality of cuts comprising perforations 30 and at least one slit 32 are made to define a removable portion 28. Next, a reclosable zipper-type fastener 12 is selected and cut to a predetermined length sufficient to overlie the removable portion 28. Opposed distal ends of fastener 12 are then "splotched" and the splotched length of fastener is disposed in adjacent, overlying relation to removable portion 28. The perimeter seal 26 is formed by the application of pressure and heat. If desired, tack seal 46 would be made in a subsequent step. From that point on, the container would be formed and filled using standard form and fill apparatus and methods. No further manipulation of fastener 12 and its related removable portion 28 is required.
[0021] It will thus be seen that the objects set forth above, among those made apparent from the preceding description, are efficiently attained, and, since certain changes may be made in the above construction without departing from the scope of the invention as defined by the appended claim, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.
(a) selecting a segment of flexible material (24) to be used for forming a container;
(b) forming a plurality of cuts (30, 32) through said segment of flexible material (24) to define a removable portion (28);
(c) selecting a reclosable zipper fastener (12) comprising a pair of mating, reclosable sealing strips (14, 16);
(d) cutting said fastener (12) to a predetermined length sufficient to overly said removable portion (28) and remain separate from the side edges of the container;
(e) forming a flat, broad seal (44) at opposed distal ends of said strips (14, 16) at each end of said length by the application of heat and pressure to yield a flattened, broadened segment (44) at each of said opposed distal ends;
(f) placing said sealed fastener (12) adjacent said flexible material (24) in overlying relation to said cuts (30, 32); and
(g) attaching said sealed fastener (12) to said flexible material (24) by forming an hermetic perimeter seal (26) around said removable portion (28) between said fastener (12) and said flexible material (24) such that said perimeter seal (26) is continuous around the perimeter of said sealed fastener (12) and separate from the side edges of the container.
(a) Auswählen eines Segmentes des flexiblen Materials (24) für die Benutzung zur Bildung eines Behälters;
(b) Bilden einer Mehrzahl von Schnitten (30, 32) durch das Segment des flexiblen Materials (24), um einen entfernbaren Abschnitt (28) zu bestimmen;
(c) Auswählen eines verschließbaren Reißverschlusses (12) mit einem Paar von zusammenpassenden, wiederverschließbaren Dichtungsbändem (14, 16);
(d) Schneiden des Verschlusses (12) auf eine bestimmte Länge, die zum Überlappen des entfembaren Abschnittes (28) ausreicht und genügt, um von den Seitenkanten des Behälters getrennt zu bleiben;
(e) Bilden eines flachen, breiten Abschlusses (44) an gegenüberliegenden distalen Enden der Bänder (14, 16) an jedem Ende der Länge durch Aufbringen von Wärme und Druck zur Erzeugung eines abgeflachten, verbreiterten Segments (44) an jedem der gegenüberliegenden distalen Enden;
(f) Anordnen des geschlossenen Verschlusses (12) neben dem flexiblen Material (24) unter Überlappen der Schnitte (30, 32); und
(g) Anbringen des geschlossenen Verschlusses (12) an dem flexiblen Material (24) durch Bilden einer hermetischen Umfangsdichtung (26) um den entfernbaren Abschnitt (28) herum zwischen dem Verschluß (12) und dem flexiblen Material (24) derart, daß die Umfangsdichtung (26) um den Umfang des geschlossenen Verschlusses (12) kontinuierlich und von den Seitenkanten des Behälters separat ist.
(a) sélectionner un segment de matériau souple (24) devant être utilisé pour former un réceptacle ;
(b) former une pluralité de découpes (30, 32) à travers ledit segment de matériau souple (24) pour définir une portion amovible (28) ;
(c) sélectionner une attache du type fermeture à glissière refermable (12) comprenant une paire de bandes d'étanchement refermables, appariées (14, 16) ;
(d) découper ladite attache (12) en une longueur prédéterminée suffisante pour recouvrir ladite portion amovible (28) et demeurer distincte des bords latéraux du réceptacle ;
(e) former une soudure plate, large (44) aux extrémités distales opposées desdites bandes (14, 16) à chaque extrémité de ladite longueur par l'application de chaleur et de pression pour obtenir un segment aplati, élargi (44) à chacune desdites extrémités distales opposées ;
(f) placer ladite attache soudée (12) adjacente audit matériau souple (24) en recouvrement par rapport auxdites découpes (30, 32) ; et
(g) fixer ladite attache soudée (12) audit matériau souple (24) en formant une soudure de périmètre hermétique (26) autour de ladite portion amovible (28) entre ladite attache (12) et ledit matériau souple (24), de façon telle que ladite soudure de périmètre hermétique (26) est continue le long du périmètre de ladite attache soudée (12) et distincte des bords latéraux du réceptacle.