US 20050282695 A1
Reclosable bags, plastic film for making the bags, and a method and apparatus for making the bags are disclosed. The bag has a reclosable fastener (26) connected to a single wall of the bag, and the film (55) has a reclosable fastener (26) connected to one side thereofwhich does not require attachment to any other portion of the film (55) when making a bag. The fastener (26) has a tamper-proof member attached thereto to indicate if the bag has been previously opened. The film (55) can be wound into a roll (54) suitable for use on conventional bag making machines including form, fill, and seal machines or a chain of coilable reclosable bags can be produced therefrom since the fasteners (26) are connected tothe web preferably transversely to the bags longitudinal formation axis. The method and apparatus for making the film (55) includes supplying a continuous web of bag making material, feeding from a coil of continuous fastener material enough fastener material to makea single fastener, (26) positioning, cutting, and attaching the fastener (26) to the film (55), with a plurality of fasteners (26) attached thereon.
1. A method for making reclosable bags comprising:
a. connecting a plurality of reclosable fasteners each with two interlocking profile strips to a rectangular sheet of film having two parallel side edges and a top and a bottom edge, each profile strip of each reclosable fastener means being maintained in the interlocked position and being independently connected to the same side of said film, said film being maintained in a flat unfolded state,
b. supplying a continuous sheet of said film with said reclosable fasteners and overlapping said side edges of said film to form a tube to enclose said reclosable fasteners on the inside of said tube, said tube having a top edge and a bottom edge,
c. sealing said overlapped side edges of said film,
d. sealing said bottom edge of said tube, and
e. sealing said tube said single bag length from said bottom edge to form a top edge of said bag to enclose a single reclosable fastener.
The invention relates to reclosable fasteners for attachment to plastic film, plastic film having a reclosable fastener transversely attached thereon, bags made from plastic film having a reclosable fastener attached thereto, and methods and apparatus for making film and bags having reclosable fasteners attached thereto. Even more particularly, the present invention is related to plastic film having a reclosable fastener thereon which may be used (a) in a form, fill, and seal packaging machine to package items in a reclosable bag and (b) to make reclosable bags which may be connected to one another.
Plastic bags are well known in the art. Such bags may be used for containing a variety of items. A popular use for plastic bags is to contain and display food items such as poultry and the like. Exemplary of the prior art are the following patents:
U.S. Pat. No. 5,116,140 discloses an easy-to-open synthetic resin bag including (a) a bag body substantially composed of a pair of laminated walls made of synthetic resin films, the peripheries of the laminated walls being heat-sealed to form a sealed border region while defining an unsealed storing space within the sealed border region, (b) a tear string which is heat sealed along an imaginary opening line on the inside of one of the laminated walls, the tear string having both ends thereof heat sealed in a sandwiched condition on the corresponding portion of the sealed border region, (c) a pulling tab formed by cutting a part of one side portion of the sealed bolder region which corresponds to one end of the tear string, the pulling tab being tearable from the bag body integrally with the tear string, and (d)a tear string retaining portion including a transverse opening which is formed by cutting off a part of the other side portion of the sealed border region and a pair of inside and outside heat sealed portions which are located at both sides of the transverse opening, the transverse opening extending in a direction perpendicular to the tear string such that the tear string passes through a central portion of the transverse opening. Due to such a tear string, retaining portion, the separation and complete removal of the tear string from the bag is reliably prevented while assuring the easy bag opening operation.
U.S. Pat. No. 5,050,736 discloses a reclosable package including interlocking closure strips positioned outside of a hermetic seal or seal area and the method for producing same. The hermetic seal is of the easy-open or peelaway type so as to not destroy the integrity of the package or closure strips upon opening of the package.
U.S. Pat. No. 5,036,543 discloses a form, fill, seal and separate packaging machine foreclosable containers to web by a plurality of stations disposed along a path of travel of a thermoplastic web including a device to attach a pair of mated, resealable closure strips to the base web. The machine is intermittent in its operation, with movement of the web through the machine controlled so that the various steps of applying the closure strips, forming, filling, sealing and separating the reclosable containers are performed during periodic stops of the machine. The machine is further characterized by its use of two pairs of web belts to move the web through the machine. A first pair of web belts initially receive the folded web stock and partially form and completely fill the containers. The second pair of web belts overlap with the downstream end of the first pair of belts, but are disposed lower than the first belts. When the filled partially formed containers pass from the first pair of belts to the second pair of belts, the unsealed free ends are exposed for final sealing and severing.
U.S. Pat. No. 5,022,530 discloses a modified zipper elements for easy open containers having interlocking zipper elements and a tear strip for opening the container along the upper edge, wherein the bases of the zipper elements are extended upward towards the tear strip to limit the area of tearing and protect the zipper elements, and a method for making.
U.S. Pat. No. 4,909,017 discloses a reclosable bag material, method and apparatus which is a new method of making a form fill bag having a reclosable fastener thereon and a mechanism therefor wherein a continuous length of film is advanced and joined first and second fastener profile strips are laid laterally onto the film of a length substantially equal to one-half of the film width, the film is advanced and formed into a tube with the side edges folded together and seamed, the first profile strip is attached to the surface of the film prior to forming it into the tube and the second opposed interlocked profile strip is attached to the inner surface of the film after it is formed into a tube, and a cross-seam is formed in the tube above the closure strip to form the bottom of the succeeding bag, and a completed bag is cut from the film by cutting below the bottom seam and above the fastener strips.
U.S. Pat. No. 4,894,975 discloses a method and apparatus for making reclosable bags with fastener strips in a form fill and seal machine from a supply of thin thermoplastic film with the film being formed into tubular shape about a filling tube with the edges of the film brought together and joined solely by a zipper strip having reclosable pressure interlocking members thereon with the zipper strip preferably heat sealed to the film and the zipper strip having a web between the pressure interlocking members which provides a tamper-evident juncture between the edges of the film so that the web must be severed for access to the interior of a bag formed from the film, and individual bags formed from the continuous tube by filing the tube through the filling tube and cross-seaming and cutting individual bags from the continuous film tube.
U.S. Pat. No. 4,782,951 discloses a reclosable package and method of making reclosable package including interlocking closure strips positioned outside of a hermetic seal or seal area and the method for producing same. The hermetic seal is of the easy-open or peelaway type so as to not destroy the integrity of the package or closure strips upon opening of the package.
U.S. Pat. No. 4,617,683 disclosed a reclosable bag, material, and method of and a device for making same wherein in one aspect extruded resiliently flexible plastic profiled reclosable fastener strip device for reclosable bags is located across the longitudinal formation axis of the bag wall web material, and in another aspect of the invention single strip fastener strip has at one or more suitable locations there along separations across the profiles, such as notches, to facilitate bending or folding of the strip upon itself so that the self-interlocking profiles of the portions of the strip folded upon themselves are adapted for reclosable interlocking with one another. The interlockable portions of the strip may have separable airtight sealing ribs therealong. The web and fastener material and fastener assembly is especially suitable for machines wherein the bags are formed, filled and sealed.
U.S. Pat. No. 4,241,865 discloses a reclosable shipping sack and method, the sack having a pouring mouth from which discrete pourable contents may be discharged, including a primary non-reclosable stitched closure fastener across and closing the mouth against unintentional discharge o the contents and including a device such as chain stitch and rip strip for facilitating digital opening of the primary closure fastener. A secondary, reclosable fastener, desirably of the zipper type, extends across the sack mouth outwardly from the primary closure fastener and is adapted for selectively opening and closing the sack mouth after opening of the primary closure fastener. A method of making the reclosable sack is also disclosed.
U.S. Pat. No. 3,473,589 discloses a plastic bag having a closure structure and a method for making same, the structure having a first thin inner layer of flexible plastic material with a first fastener element extending therealong formed of a resilient material and being of one piece with the layer, a second thin layer of flexibly plastic material facing the first layer and having a uniform second fastener element extending therealong formed of a resilient material and being of one piece with the second layer and shaped to be releasably interlocked with the first fastener element, a first outer layer positioned over the outer surface of the first inner layer and laminated thereto, the first inner and outer layers providing a first substantially monolithic wall so that the first inner layer provides a support with the layers coacting and allowing a stronger lock with a thin film, and a second outer layer positioned over the outer surface of the second inner layer and laminated thereto, the second inner and outer layers providing a second substantially monolithic wall so that the second inner layer provides a backing for the support allowing a stronger lock with a thin film, the outer layers laminated to the inner layer opposite fastener elements so as to reinforce the inner layers in the area of the fastener elements.
In accordance with the first embodiment of the present invention there is provided a reclosable bag made from plastic film having reclosable fastener assemblies thereon, film having a reclosable fastener assembly attached thereon, and a method for making reclosable bags from plastic film having reclosable fastener assemblies thereon. The reclosable bag has a reclosable fastener assembly connected to a single wall of the bag, and the film has a reclosable fastener connected to one side thereof which does not require attachment to any other portion of the film when making a bag. The fastener may have an easy bag opening tamper-proof member attached thereto to indicate if the bag has been previously opened.
The film of the invention has the advantage of having a reclosable fastener assembly completely connected thereto prior to being fed to a bag making machine or a form, fill, and seal machine, thereby eliminating the need to apply a reclosable fastener assembly during the bag making process or during the form, fill, and seal process, thereby eliminating the need for the equipment necessary to add a reclosable fastener during the form, fill, and seal process.
The film of the invention has the additional advantage of being capable of forming a reclosable bag on a vertical or horizontal form, fill, and seal machine.
The bag and film of the invention has the advantage of allowing the reclosable fastener assembly to be located at any desired distance from the top or bottom of the bag because thefastener assembly is attached to only one wall of the bag of the invention. The length of the fastener assembly may be much less than the width of a bag formed with the fastener assemblythereon. Such small length fasteners allow liquids, powders, and other small granular materials to be poured from the bag through the fastener assembly.
A good use for the bags of the invention when the ends of the fastener assembly are not sealed to front wall of the bag is to store non-perishable items such as ice glazed food products that are not susceptible to freezer burn since air and moisture is able to enter the bag around the ends of the fastener assembly after the front wall of the bag has been penetrated to gain access to the fastener assembly or even before the bag wall has been penetrated such as when a line of perforations is utilized for allowing easy access to the fastener assembly.
In accordance with the first, second and third embodiment of the present invention there is provided a method for making reclosable bags on a bag making machine where the reclosable fastener strips are independently attached to the same side of the bag film preferably transversely to the longitudinal forming axis in-line with the bag making machine, a unique two-piece interlocking fastener assembly that minimizes the size of the opening at the fastener strip ends, film having a plurality of the unique reclosable fasteners each with two interlocking profile strips attached thereon, and an apparatus for attaching the unique fastener assembly to a sheet of film including a mechanism for supplying a continuous film of flexible bag material and a mechanism for feeding preferably the coiled reclosable profile strip material preferably transversely across the bag material film, and a mechanism for positioning, cutting, and attaching enough of the reclosable profile strip material to form a preferably transversely positioned reclosable fastener for a single bag during each cycle of the apparatus, the reclosable fasteners each being spaced a single bag length apart and each profile strip of eachreclosable fastener being maintained in the interlocked position and being independently connected to the same side of the film that forms one panel of the resulting bag. The bag material can be wound into a roll in the folded or unfolded state or fed directly into a conventional form, fill, and seal machine that is in-line with the apparatus for positioning andattaching the reclosable fastener strip material to the bag material web.
In accordance with a fourth embodiment of the present invention there is provided a chain of coilable interconnected reclosable bags and a method for making the same. A chain of bags are interconnected by a series of preferably transverse cross-seals including a plurality of spaced tearlines between adjacent bags. Each bag of the coilable chain includes preferably a transversely positioned reclosable fastener secured to the outer or inner surface of materialthat forms its front wall. The present invention allows a single bag to be easily torn away from the chain of bags.
The method of making the chain of coilable reclosable bags includes supplying a continuous film of plastic web material and moving said film forward in a bag forming direction. A plurality of reclosable fasteners are secured to the surface of the web material, that forms the front wall of each bag, preferably transversely across the web. The web is drawn forward bringing the inside surface of said web material that forms the front wall of each bag next to the surface of a web material that forms the back wall of each bag. The longitudinal edges of the web materials that form the front and back wall of each bag are sealed together to form a tube of plastic web material.
The front wall and back wall of the tube are cross-sealed to each other to form the topand bottom end of each bag. A tearline is cut in the tube between the seals of each bag and the chain of bags are coiled into a roll. The method can include the application of a twin sealwith a tearline between them thereby creating a closed top end and a closed bottom end on each bag or a single seal and tearline can be applied which creates an open end and a closedend on each bag. The method of the present invention also includes a rupturable line of weakness applied to the front wall of each bag adjacent to the reclosable fastener for entering the bag. The reclosable bags on a roll can be conveniently used by the customer. The reclosable bags of the present invention also have the unique property of being less likely to leak when the bag is placed on its back wall with the reclosable fastener facing up.
Referring now to the drawings, in
Bag 10 has a seal 20 at the top end 12 at which the front wall 16 is joined to the back wall 18, and a seal 22 at the bottom end at which the front wall 16 is joined to the back wall 18. Located on the back wall 18 is a seam generally indicated by the numeral 24.
As best can be seen in
Each end 26 a and 26 b of reclosable fastener assembly 26 is preferably sealed in any conventional manner such as heat sealing to the inside of front wall 16 to prevent air or liquids from entering or leaving bag 10 through the ends 26 a and 26 b of reclosable fastener assembly 26 after the front wall 16 has been opened by the user of the bag 10 to gain access to reclosable fastener assembly 26. However, if desired, the ends 26 a and 26 b need not be sealed to the inside of front wall 16, and after opening front wall 16, air or liquids can enter or leave bag 10 through the ends 26 a and 26 b of bag 10 and through the opening in front wall 16.
The bag 10 is air tight prior to opening the front wall 16 to gain access to reclosable fastener assembly 26. Therefore, products can be vacuum packed in bag 10.
Groove 32 is formed in groove body 36, and groove body 36 is connected to groove body arm 38. A portion of groove body arm 38 is connected to the inside of front wall 16 at seal 40. Groove body arm 38 could be made separately from groove body 36 and attached to groove body 36 in any conventional manner such as heat sealing.
Protuberance 34 is integrally connected to protuberance body 42, and protuberance body 42 is integrally connected to protuberance body leg 44. A portion of protuberance body leg 44 is connected to the inside of front wall 16 at seal 46. Protuberance body leg 44 could be made separately from protuberance body 42 and attached to protuberance body 42 in any conventional manner such as heat sealing.
A string 48 for tearing a portion of front wall 16 to expose and provide access to reclosable fastener 26 is located adjacent to the inside of front wall 16 and seal 40. String 48 has an exposed end 50 connected to pull tab 52 for grasping by the customer and pulling to tear a portion of the front wall 16 covering reclosable fastener 26. If desired, string 48 could be replaced with a plurality of perforations in front wall 16 between seal 40 and protuberance body 42. If desired, string 48 and the plurality of perforations in front wall 16 could be omitted from bag 10, and the portion of front wall 16 between seal 40 and protuberance body 42 could be opened with a sharp object such as knife or scissors.
A roll of film 54 on a paper core 54a placed on an axle or roller 56 containing the reclosable fastener 26 is shown in
To make the bag 10 of the invention from the roll of film 54, each side 56 and 58 of the film 54 is folded together as shown in
Any conventional bag making film known in the art may be utilized as the film stock to make bag 10. The seals of the invention are preferably made by heat sealing as is well known in the art. Such bag film is commonly referred to as plastic film, and is commonly made from polymeric materials.
Referring now to
Bag 110 has a generally horizontal seal 120 at the top end 112 at which the front wall 116 is joined to the back wall 118, and a seal 122 generally parallel to seal 120 at the bottom end at which the front wall 116 is joined to the back wall 118. Located on the back wall 118 is a seam generally indicated by the numeral 124 which is generally perpendicular to seal 120 and 122.
As can best be seen in
Groove 132 is formed into groove body 136, and groove body 136 is connected to groove body arm 138. A portion of groove body arm 138 is connected by heat-sealing or welding to the inside of front wall 116 at seal 140. As shown in
Peelable seals such as peelable seal 141 are well known in the art and are disclosed in U.S. Pat. No. 5,050,736, which is hereby incorporated by reference. Peelable seals such as peelable seal 141 are made to peel open easily using minimal opening forces by utilizing lowsealing temperatures, reduced dwell time, and light pressures. Peelable seals can also be produced by utilizing a single polymer or from a combination of polymers that molecularly produce low seal strengths.
As can best be seen in
As can be seen in
Thus, to open a bag 110 that has been filled with a desired product such as rice, cereal, meat, or the like, pull-out plug 150 is torn or pulled out as explained above to expose and provide access to reclosable fastener 126 through opening 153 a. Profile strip 130 is then pulled away from profile strip 128, forcing peelable seal 141 away from sealing contact with the inside of front wall 116. The interior of bag 110 may then be accessed through opening 153 a, between profile strips 128 and 130, and between front wall 116 and peelable seal 141. As mentioned above, pull-out plug 150 could be replaced with a line of perforations or line of weakness or a continuous sheet of film, and reclosable fastener assembly 126 would be accessed by tearing the line of perforations or weakness, or opening the sheet of film with a knife or scissors.
Each end 126 a and 126 b of reclosable fastener assembly 126 is preferably sealed at seams 126 c and 126 d in any conventional manner such as heat sealing to the inside of front wall 116 to prevent air or liquids from entering or leaving bag 110 through the openings 125 a and 125 b at ends 126 a and 126 b of reclosable fastener assembly 126 after the front wall 116 has been penetrated by the user of the bag 110 to gain access to reclosable fastener assembly 126. However, if desired, the openings 125 a and 125 b at ends 126 a and 126 b need not be sealed to the inside of front wall 116, and after penetrating front wall 116, air or liquids can enter or leave bag 110 through the openings 125 a and 125 b at ends 126 a and 126 b of bag 110 and through the penetrations in front wall 116.
Groove body arm 138 and groove body leg 139 could be an integral part of groove body 136 or as shown in 6B could be made separately from groove body 136 and attached to groove body 136 during a separate operation in any conventional manner such as heat sealing. Groove body arm 138 and groove body leg 139 could be opaque in color for optically identifying where one bag should end and another bag begins without having to print some type of colored identifier on the film at each bag location.
To make the bag 110 as shown in
As shown in
As shown in
As can best be seen in
As shown in
Any device known in the art for providing easy opening features could be utilized. The location of the mechanism 180 for providing easy opening could be incorporated into the apparatus 170 for making roll of film 154 anywhere desirable, but the mechanism 180 would preferably be located in a place whereby the easy opening feature would be provided in or on the film 155 immediately prior to the attaching of reclosable fastener assembly 126 onto film 155.
The apparatus 170 for making rolls of film 154 includes a rewinding device 182 for winding film 155 into a roll on a supporting core 154 a or into coil 60 without supporting core material as shown in
The apparatus for making zippered film could be connected to a form, fill, and seal machine, that is, provided in-line or part of the form, fill, and seal machine. As a result the method for making bag 110 would not require that film 155 be formed into a roll of film 154 since the film 155 would be fed directly into the form, fill, and seal machine. The device 182 for rewinding the film into roll 154 would not be a required part of the apparatus for making zippered film when the in-line method is used. As a result of not having to wind film 155 into a roll 154, film 155 could have the fastener assemblies 126 attached by apparatus 170 parallel to the longitudinal forming axis of film 155 as shown in
Any conventional bag making film known in the art may be utilized as a film stock to make bag 110. The seals of the invention are preferably made by heat sealing as, is well known in the art. Such bag film is commonly referred to as plastic film, and is commonly made from polymeric materials.
As can best be seen in
Reclosable bag 1010 could be formed from J-sheeted film 1155 which includes reclosable fastener assemblies 1266 that have been attached by a machine, such as apparatus 170 shown in
Referring now to
Each bag 210 has a seal 220 a at the top end 223 and a seal 220 b at the bottom end 224 at which the front wall 211 is joined to the back wall 212. Each bag 210 has side edge seals 221 a and 221 b at which the front wall 211 is joined to the back wall 212.
As can best be seen in
A flange 216 is connected to the outside of profile strip 214. Flange 216 is connected to front panel 211 along flange edge 219. A rupturable perforation line 217 in front wall 211 provides a tear line for tearing open to enter bag 210 once the reclosable fastener 213 is opened. Each end 216 a and 216 b of flange 216 is preferably secured to front wall 211 in any conventional manner such as heat sealing to the front wall 211 to prevent air or liquids from entering or leaving through flange ends 216 a and 216 b. However, if desired, the flange ends 216 a and 216 b need not be sealed to the front wall 211 so air and liquids can enter or leave bag 210 through the flange ends 216 a and 216 b.
The flange 216 could be integrally connected to the profile strip 214 or as shown in
Reclosable fastener 213 with attached flange 216 could be replaced with any of the previously described fastener arrangements such as shown in
The collapsed tubular web 218 or reclosable bags 210 is formed by connecting a plurality of bags 210 together by perforation lines 222 extending across the tube 218 transversely to the side edge seams 221 a and 221 b and between the top end seals 220 a and bottom end seals 220 b of two adjacent bags 210.
The preferred method of producing the collapsed tubular web of reclosable bags of the present invention according to
Back wall web material 212 is diverted around sealing device 256 by passing over preferably at least one additional idler roll 253. At nip section 258 the web materials that form the front wall 211 and the back wall 212 are rejoined by passing through two preferably driven nip rolls 258 a and 258 b where they are secured together by continues seams along the longitudinal edges 224 a and 224 b of front wall 211 and the longitudinal edges 224 c and 224 d of back wall 212 by any conventional method such as heat sealing.”
The web materials that form front wall 211 and the rear wall 212 with their peripheral edges 224 a, 224 b 224 c, and 224 d, sealed together reform a tube 218 with a plurality of spaced reclosable fasteners 213 and perforation lines 217 transversely secured a bag's length apart along the length of tube 218.
The tube 218 passes through a cutting cross-sealing device 260 that applies one bag stop end seal 220 a and the adjacent bags bottom end seal 220 b simultaneously while cutting the perforation line 222 extending transversely across the tube 218 and between the top end seals 220 a and bottom end seal 220 b. Such cutting sealing devices are well known in the art. U.S. Pat. No. 4,449,962 shows a typical cutting sealing device with the exception that a straight cut is included for making separated bags. While the present invention could also produce separated bags the preferred embodiment is bags connected to one another by the perforation lines 222 between adjacent bags. The device of U.S. Pat. No. 4,449,962 could accomplish this by utilizing a serrated knife, and U.S. Pat. No. 4,449,962 is hereby incorporated by reference.
The tube 218 has been converted, as described above, into a series of reclosable bags 210 connected together making it possible to wind them into roll 262 by any conventional winding machine 263. The reclosable bags 210 can be wound onto any preferred core material 264 such as a paper tube or can be would into roll 262 without any supporting core material 264. Roll 262 can be produced with any desired number of reclosable bags 10 making up the roll 262.
As shown in
Although the preferred embodiments of the invention have been described in detail above, it should be understood that the invention is in no sense limited thereby. Other variations are possible. For example referring to the fourth embodiment, a single web of material could be unwound from a roll and folded, out of line with blown film tube extrusion machine 250, after the reclosable fasteners 213 have been attached and the perforated bag openings 217 have been applied. Then the side opposite the fold could be sealed closed and the remaining steps of the method of making reclosable bags on a roll according to the present invention would follow as previously described above. Also a device for staggering the bags could replace the winder so as to fan fold stack the interconnected bags into a container in a zigzag fashion versus winding them into a roll. Furthermore, the top end 223 of each bag 210 could be unsealed so the series of bags could be dispensed from the roll with one end open, allowing product to be loaded through the open end and later sealed shut by the user after loading. The rupturable line of weakness 217 could also be eliminated requiring the user to cut each bag open or a tear string could be incorporated to assist in creating an opening adjacent the reclosable profile strips 214 and 215 of each bag 210. In addition the front wall 211 could be formed from a transparent flexible film and the back wall 212 could be formed from C a opaque flexible film. As taught in the fourth embodiment, many other applications could utilize a film with pre-applied reclosable fasteners that are greater than half the width of the web each located a bag length apart with each profile strip independently connected to the same side of the film, such as, lidding films for vacuum formed trays or lidding films covering forming webs used in vacuum packaging.
Many of the elements of the various embodiments of the present invention could be interchanged with one another, e.g., the reclosable fastener assembly of the second embodiment could be substituted for the fastener assembly of the third embodiment and vice versa. The fastener assemblies of the present invention could not only be interchanged, but they could be positioned transversely or parallel to the longitudinal forming axis of the zippered film as shown in