JPH0436941B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides pegs and
The present invention relates to a thermoflexible bag that can be hung in a filled state from a board-type display. In particular, the present invention relates to heat-shrinkable and side-sealed thermoplastic bags used for the packaging of processed meats and cheeses displayed for retail sale.

In retail stores and supermarkets, many processed meat and cheese packages are hung on peg boards for easy viewing by customers. There are many different ways in which it can be hung. Straps or hooks that can be secured to the packaged package in the retail store can be used, for example a strip of semi-rigid plastic with a hook at one end, or alternatively a cone to hold the filled bag. Alternatively, you can use cut-out paper patterns that can be shaped into straps. Another type of hanging configuration consists of drilling holes at either end of the bag and reinforcing this hole with metal or plastic eyelets to provide a sufficiently strong suspension means. A further alternative is a loop or strap that is welded to the bag as it is formed. It is this last configuration that the present invention relates to.

HLFarmer U.S. Pat. No. 3,207,300, issued September 21, 1965, discloses a heat-sealable, heat-shrinkable plastic film wrap surrounding an article and a heat-shrinkable plastic film wrapper within the wrapper that is within the heat seal. A label containing a semi-rigid product having a printed label of a thin strip of heat-sealable and heat-shrinkable plastic film with each fixed strip end extending across the product. package is shown. However, the strip will shrink with the wrapping material and will not form a loop to form a hanging strap. Accordingly, one object of the present invention is to provide a package having a shrinkable wrapping material and a non-shrinkable strip or strap that can be used for hanging.

For packaging many foods, especially fresh or processed meats, it is particularly desirable to use packaging materials with low oxygen permeability. For one such material, see HJ, published June 26, 1973.
Brax et al., US Pat. No. 3,741,253. The Brax et al. patent describes a packaging film having a first layer of extruded cross-linked ethylene vinyl acetate copolymer coated with another layer of ethylene vinyl acetate copolymer. If the strap is welded to a non-crosslinked vinyl acetate polymer layer, the Brax
When using bags made from the film of the U.S. Pat. It was found that there was a risk of damage in a short period of time. It is therefore another object of the present invention to provide a hanger bag which can be used with fat-containing products and which can be hung on a retail display shelf for an extended period of time.

These and other objects will be better understood upon consideration of the summary of the invention, the drawings, and the detailed description below.

In one aspect, the invention resides in a handle bag having a bag portion including front and back panels made of multilayer heat-shrinkable thermoplastic sheet material;
In this, at least two layers of multilayer material are extruded together, the panel consisting of a sheet folded so that the folded portion forms the bottom of the bag, and the edges on each side of the panel Heat shrink sealed against each opposite side edge in parallel side seals, leaving unsealed sides defining the top of the bag with an opening for filling the bag with product. A strap of non-stick heat sealable material is provided, one end of which is sealed against the seal on one side and the other end is sealed against the seal on the other side, thereby causing the bag to heat up. When deflated, the bag retracts away from the strap to form the strap into a loop for suspending the bag.

In another aspect, the invention does not require that two of the layers of the multilayer film be extruded at the same time, but that the straps are made of superimposed strips of heat-shrinkable and non-heat-shrinkable material. The present invention relates to a bag with a handle, in which a retractable strip of material is next to or in contact with the bag.

In yet another aspect, the invention provides an article of manufacture;
This article consists of a multi-layer side-seal thermoplastic plastic bag that is shrunk around the circumference, the material from which said bag is formed consisting of a multi-layer film with at least two layers simultaneously extruded and heat-sealed. including a hanging loop constituting a non-heat shrinkable strap of possible thermoplastic material, one end of said strap being attached to the outer surface of said one layer of co-extruded material at one of said side seals. The other end of the strap is sealed against one outer surface of the coextruded layer at the other side seal.

In yet another aspect, the present invention relates to a method of making a hanger bag, the method providing a flat heat-shrinkable thermoplastic tubular material, the material from which the tubular material is formed having multiple layers. and the layer constituting the outer surface of the tubular material is extruded simultaneously with its adjacent layer, and the flat tubular material is extruded at or adjacent one longitudinal edge. making cuts, superimposing a strip of non-shrinkable material on the tubular material, and making perforations between the tubular material and the superimposed strip at mutually parallel intervals along the length of the tubular material. said flat tubular material is passed through sealing and perforating means arranged to form two successive transverse seals having orations, said flat tubular material being sealed by said sealing means to itself and said strip. and sealing the strip to each side seal having perforation between the seals to form a side seal bag.

The invention will be better understood by examining the drawings.

In FIG. 1, a flat tubular material 2 is shown being guided on guide rolls 3 past a sealing and perforating device 4. In FIG. The flat tubular material is preferably made from a multilayer thermoplastic film of low oxygen permeability; one such film is described in the aforementioned Brax et al. patent. In another preferred film, a substrate of ethylene vinyl acetate copolymer containing about 9% vinyl acetate is extruded, crosslinked by radiation, and then coated by extrusion with two coextruded layers. It is something that will be done. The two layers melted simultaneously and extruded onto the substrate is very similar in operation to single layer extrusion coating. The two co-extruded layers that make up the extruded coating are a vinylidene chloride copolymer layer of the type disclosed in the Brax et al. patent, and an ethylene vinyl acetate copolymer layer containing about 9% vinyl acetate. This vinylidene chloride copolymer layer is in contact with the substrate and an ethylene vinyl acetate copolymer layer is present on the outside. Thus, considering FIG. 1 again, the outer surface of the flat tubular material 2 is made of ethylene vinyl acetate copolymer that is not in a cross-linked state, and the inner surface of the tubular material that is in contact with each other is made of a cross-linked Consisting of state ethylene vinyl acetate copolymer. The tubular material is preferably cut at the side edge opposite from where the substrate 8 is fed from the roll 7, and this cut edge will of course provide a mouth or opening in the finished bag. Cutting devices are well known in the art and are not shown in the text.

When the cut tubing enters the sealing device, a strip of strap material 8 is laid on top of the tubing. The strip 8 is preferably made of low density polyethylene or ethylene vinyl acetate copolymer and is not oriented or stretched to provide some degree of heat shrinkage.
This material must, of course, be a heat-sealable thermoplastic material and can be sealed together with the tubular material in the sealing and piercing device 4. A typical width of this strap material is 25 mm (or approximately 1 inch).

The width of the flat tubing will vary depending on the product to be packaged in the finished side seal bag, but typical widths of the flat tubing are 25 to 30 mm (1.0 to 1.2 inches). ).

The sealing device 4 may be any commercially available sealing and cutting device. These are well known in the art and typically seal when the opposing members of the sealing device 4 are pressed together through the straps 7 onto the tubular material when a current pulse is applied. Consists of electrical resistance wire that is heated to a temperature. In fact, this sealing device 4 has two sealing wires forming a spaced seal 5, and furthermore, said sealing device drills a perforation 6 into the flat tubular material 2 and into the strap 8. It has a punching device. These perforations are typically 63.5mm to 76.5mm
mm (2.5 to 3 inches) apart, and the residence time when the sealing member is closed to form the side seal is 1/
It will take about 4 to 1/2 seconds. In FIG. 1, after the sealing and piercing operations have been carried out, the sealing device 4 results in a flat side seal bag 9 which still adheres to the subsequent bag being formed. Side-sealed bags are generally considered to be sealed on at least one side by a seal and defined by a fold at the bottom.

In FIG. 2, the side seal bag 9 is now separated from the tubular material and ready for filling. Filling can be accomplished manually or by any means, and involves loading a wide variety of products, especially food products such as meat and cheese, into the mouth of the bag at the end opposite the strip 8. I can do it. In the typical case described below, 500g of processed meat, such as sausage, is placed in a bag, the bag is evacuated by means well known in the art, such as a vacuum device or a vacuum nozzle device, and the bag opening is Heat sealed. One suitable configuration is the Cryovac Division of WR Grace & Co., Duncan, South Carolina, USA.
There is a model 8300 rotary vacuum generator commercially available. A heat seal similar to that produced by impact sealing device 4 can be used or metal clips can be used. After the final closure seal has been carried out, the filled bag is heated to within the range of approximately 85-96°C (185-205〓) in order to shrink the unsealed bag 9 so that it clings around the piece of meat. Simply immersing the bag in hot water results in the package assuming the appearance shown in FIG. 3 in which the bag 9 contracts and the strap material 8 forms a loop 8 for hanging purposes.

In Figure 4, a peg 1 on which a bag or package 9 filled with a loop 8 is suspended, as is common in many supermarkets.
A display peg board 10 having 1 is shown.

When a single layer strap is attached to a multilayer bag material that is not extruded simultaneously, fat from the filled product can erode the strap seal at high temperatures, such as heat shrink temperatures, and cause the outer layer of the bag to It was found that there was a risk of peeling.

Surprisingly, it has been found that this delamination problem can be solved by coextruding at least two layers of the multilayer film from which the bag is formed. One of these layers is the layer to which the ends of the strap 8 are heat sealed.

In a test to determine the reliability of the suspension loop of the present invention, peanut oil was applied to the inside of the bag before packaging the meat, and the bag was then suspended from the loop at a temperature of 32°C. Bag configurations that were not simultaneously extruded were found to fall off either immediately or after a short period of time in this test using 500 grams of product. Meanwhile, bags containing 500 g of meat pieces in a coextruded configuration were suspended by straps at a relatively low temperature (8° C.) and at room temperature. The product was left hanging on a hanging shelf until the 30th, but no problems occurred.

In addition to the discovery that the coextrusion structure described above significantly eliminates the strap breakage problem, the addition of approximately 50 mm (2 inches) of heat-shrinkable film, such as heat-shrinkable polyethylene, to one side of the tubular material It has also been found that a satisfactory handle bag can be obtained if a non-shrinkable strap is welded to the top of the shrinkable film after a relatively wide strip of material has been installed. It has been theorized that a wide band of shrinkable film that contracts with the tubular material from which the bag is formed will distribute the forces acting on the strap over a relatively long distance of the outer layer of bag material. This kind of structure is made up of strap material 8 from roll 7.
can be constructed as shown in Figure 1 by adding two layers of strips, the first layer being a thermoplastic, heat-shrinkable material; The overlapping second layer is a non-shrinkable material that provides a hanging loop. As previously mentioned, these two layers of strapping material 8 are applied in the same way as a single layer, but upon shrinking the shrinkable layer shrinks with the bag material and the non-shrinkable material does not, so that the previous example Form a hanging loop like this. The width of the hanging loop will be 25 mm as before, and the width of the retractable film will be approximately 50 mm (2 inches).

As mentioned above, one of the main objects of the present invention is to provide a bag with a handle that is both heat-shrinkable and has low airtightness. When used as one layer in a multilayer film, hydrolyzed ethylene vinyl acetate copolymers provide excellent resistance to gas permeation, and in the Brax et al. Although producing excellent resistance to permeation, single layer films of vinylidene chloride copolymers are said to not compromise the resistance necessary to withstand commercial distribution. Thus, while the Brax et al. patent describes the discovery of multilayer films containing vinylidene chloride copolymer layers in a unique combination of heat-shrinkable and rough-handling resistant materials, in the present invention Brax et al. Although it is desirable to use a multilayer film such as that described in the patents of J.D. et al., the addition of strapping material to such a multilayer film in high-speed bag manufacturing processes is such that the fat-containing product is packaged within the bag and shrinks at high temperatures. When forced to do so, the result is an unacceptable defect rate. Solutions to this problem, which can be expected to occur in other multilayer films used for the packaging of fat-containing foods such as raw meat, smoked meat, cured meat and cheese, are described in the text and in the preface. It is summarized in the claims.

[Brief explanation of drawings]

FIG. 1 is a diagram illustrating the method of forming tubular material and strap material into a bag with side-sealed handles; FIG.
FIG. 3 is a perspective view showing a bag with a handle in an unfilled state and an unshrinked state according to the present invention; FIG. The figure shows a package according to the invention displayed on a peg board in a retail supermarket. 1...Roll, 2...Tubular material, 3...Guide roll, 4...Sealing and perforation device, 5...Seal, 6...Perforation, 7...Roll,
8...Strap, 9...Side seal bag,
10...Peg board.

Claims (1)

[Scope of Claims] 1. A heat-shrinkable bag with a handle having low oxygen permeability, which includes: (a) a bag portion, the bag portion comprising (i) a multi-layered bag having at least two layers extruded simultaneously; having front and rear panels made of heat-shrinkable thermoplastic sheet material; (ii) said panels comprising a single sheet folded to form the bottom of said bag; iii) both sides of each of said front and rear panels are sealed along their side edges to the corresponding sides of the other panel to provide parallel side seals and the top side is unsealed; (b) providing a strap made of a non-heat shrinkable sealable material, one end of the strap being the bag is sealed against one side seal and the other end is sealed against the other side seal so that when the bag is heated and shrinks it contracts away from the strap; A bag with a handle, characterized in that the strap is formed into a loop for hanging the bag. 2 The multilayer film of the bag consists of three layers, the layer forming the inner surface of the bag is a crosslinked ethylene vinyl acetate copolymer, the middle layer is a vinylidene chloride copolymer, and the outer layer is an ethylene vinyl acetate copolymer. 2. The bag of claim 1, wherein the bag is an acetate copolymer, and wherein the middle layer and the outer layer are coextruded onto the inner layer. 3. A bag with a handle according to claim 1, wherein said strap is located adjacent to the bottom of said bag. 4. A heat-shrinkable handle bag with low oxygen permeability, comprising: (a) a bag portion, which portion (i) has a front and rear portion made from a multilayer heat-shrinkable thermoplastic sheet material; (ii) said panel comprises a sheet folded to form the bottom of said bag; and (iii) each side of said panel has opposite side edges thereof. (b) sealed to the other panel along with a parallel side seal, leaving the unsealed side to define an opening in the bag for filling goods into said bag; two superimposed straps, one heat-shrinkable and one non-heat-shrinkable, said heat-shrinkable strap being in contact with a surface of said bag such that said bag is heat-shrinkable; A bag with a hanger, characterized in that, when the bag is contracted, the contractible strap contracts away from the non-heat-shrinkable strap together with the bag, thereby forming a loop for hanging the bag. 5. A bag with a handle according to claim 4, wherein said strap is located adjacent to the bottom of said bag. 6. (a) an article; (b) a heat-shrinkable thermoplastic bag having side seals and contracted around said article, the material of said bag comprising at least two simultaneously extruded layers; (c) providing a hanging loop of non-heat shrinkable thermoplastic material, one end of the loop being sealed against one side seal and the other end of the loop being sealed against the other side seal; A package cage for hanging display characterized by being sealed against a seal. 7. The material from which the side seal bag is formed consists of at least three layers, at least two of which are extruded simultaneously, and at least one of the layers is made of vinylidene chloride copolymer and hydrolyzed ethylene vinyl acetate. 7. A package according to claim 6, characterized in that it is selected from the group consisting of copolymers. 8. A package according to claim 6, characterized in that the product is selected from the group of foods consisting of raw meat, smoked meat, preserved meat and cheese. 9. The package of claim 6, wherein said hanging loop is located adjacent the bottom of said bag. 10 (a) an article; (b) a thermoplastic bag having side seals and contracted around said article, the material from which the bag is formed comprising a multilayer thermoplastic material; ( c) a heat-shrinkable strap whose ends are sealed to opposite side seals of said bag and shrunk with said bag; and (d) made of thermoplastic material superimposed on said shrunkable strap. a non-heat-shrinkable strap, one end of the strap being sealed to one side seal and the other end of the strap being sealed to the other side seal; A package, thereby providing a hanging loop for the bag, characterized in that the ends of the non-collapsible strap and the collapsible strap are sealed together. 11. The package of claim 10, wherein a retractable strap and a non-retractable strap are located adjacent the bottom of the bag. 12. A package according to claim 10, characterized in that said product is selected from the group of foods consisting of raw meat, smoked meat, cured meat and cheese. 13 (a) providing a flat heat-shrinkable thermoplastic tubular material, said tubular material comprising a multilayer thermoplastic film having at least two simultaneously extruded layers; (b) said flat cutting the tubular material along one of its edges; (c) superimposing a strip of non-shrinkable material on the tubular material; and (d) sealing and perforating the tubular material and the superimposed strap material. forming a continuous seal across the width of said tubular material being passed through the device, said seals being parallel to each other; (e) strap material sealed at side seals with said sealing device; 1. A method for manufacturing a bag with a handle, the method comprising forming a side seal bag having a side seal. 14. The method of claim 13, including positioning a strap adjacent an end of the bag and away from the opening.