Easy to remove overwrap

A tubular film package comprising a tubular film provided with a tear strip secured upon an outside surface of the film. The tear strip is defined by a longitudinal edge of the film and a heat seal joint provided in the film essentially parallel to the longitudinal edge. The film is further provided with at least one slit running from an end of the film to the heat seal line so that pulling of the strip away from the package commencing at the slit causes film to separate proximate the heat seal line thus opening the package.

BACKGROUND OF THE INVENTION
 This invention relates to packages for food casing strands.
 Food casing strands are shirred tubular film food casing. "Shirred" means
 radially folded so as to be compressed along the longitudinal axis of the
 tubular film.
 Such shirred food casings are packages for storage and shipment to food
 processors, e.g. meat packers making cylindrically shaped sausage product.
 Numerous types of packages for shirred food casing have been used in the
 prior art. Such packages have included rigid cartons as well as net and
 film wrappings.
 Film wrappings have had certain advantages, e.g. they are light weight and
 usually provide a moisture barrier to prevent dehydration of moisturized
 strand products.
 One difficulty with film packages for food casing strands has been that a
 film which is strong enough to provide a secure package is generally
 difficult to remove from the packaged product.
 This problem has been addressed by providing adhesive opening strips or
 areas which can be readily removed to provide access to package contents.
 Unfortunately such adhesive strips have caused yet another problem in that
 after removal they tend to stick to undesirable areas creating
 disorganization and a generally messy environment.
 In another known film packaging system, tape is provided along the length
 of the package and perforations or other weakened areas are provided along
 the edges of the tape so that a portion of packaging film is removed with
 the tape. The adhesive portion of the tape is thus covered by removed film
 which prevents problems associated with sticky removed tape. Such a
 package still has some disadvantages in that the film must be processed to
 provide weakened areas and there is a cost associated with the use of
 adhesive tape.
 In essentially all cases in the prior art, at least one end of a package
 for a shirred casing strand must be opened before the strand can be placed
 on a stuffing horn to fill the casing with food product. Opening the
 package holding a strand, especially of fibrous casing, creates a risk
 that the strand will break along a helical fold thus making it very
 difficult or even impossible to load onto the stuffing horn. Furthermore,
 opening a package containing a strand of food casing before placement on a
 stuffing horn creates an increased risk of contamination.
 None of the prior packages for food casing strands permit placement of the
 strand within a sealed package on a stuffing horn without opening the
 package while permitting easy removal of the packaging material while the
 stand remains on the stuffing horn.
 It is therefore an object of the invention to provide a readily openable
 film package for food casing strands which overcomes the previously
 described disadvantages of prior art film packages.

BRIEF DESCRIPTION OF THE INVENTION
 The invention comprises a tubular film package comprising a tubular film
 provided with a tear strip secured upon an outside surface of the film.
 The tear strip is defined by a longitudinal edge of the film and a heat
 seal joint provided in the film essentially parallel to the longitudinal
 edge. The film is further provided with at least one slit running from an
 end of the film to the heat seal line so that pulling of the strip away
 from the package commencing at the slit causes film to separate proximate
 the heat seal line thus opening the package. In one embodiment the package
 further comprises at least one tubular food casing strand encased therein
 so that the film encompasses the strand. In a further embodiment the
 strand has an exterior surface, an internal cylindrical bore and an
 interior bore surface and the tubular film is in contact with and covers
 both the exterior surface and internal bore surface of the strand and the
 tear strip extends along the length of the film along both the exterior
 and interior surfaces of the strand and so that ends of the tubular film
 are in contact and provided with a seal to completely enclose the strand
 while permitting access to a hole through the bore of the strand.
 DETAILED DESCRIPTION OF THE INVENTION
 The shirred tubular film to be packaged in accordance with the present
 invention may be of any suitable material, e.g. cellulose, collagen,
 polyolefin, and polyvinylidene chloride and may be unreinforced or
 reinforced e.g., with fiber randomly dispersed or in the form of a woven
 or non-woven web.
 The tubular film may be used to package any suitable food product, e.g.,
 sausages such as hot dogs, bolognas, salamis, fresh sausage, lunch meats
 etc., whole meats such as hams or turkey breast or other food product such
 as cheeses.
 The plastic film encompassing the strands may be of any suitable heat
 sealable material, e.g., polyvinylidene chloride coated cellulose,
 polyvinylidene chloride, polyethylene and polypropylene. The plastic film
 may have shrink wrap characteristics, e.g., the strands may be placed in a
 tubular plastic film and the film shrunk over the strands to provide
 secure containment. The film may also have stretch characteristics so that
 it can be stretched over the strands and then relaxed to secure the
 strands.
 In accordance with a preferred embodiment of the invention, the tubular
 film package may extend over the ends of the material to be packaged,
 e.g., food casing strands, and may be secured, e.g., clipped, glued, heat
 sealed or tied, over the ends of the material to provide a liquid tight
 package. The package ends are preferably heat sealed. It is however, to be
 understood that the quick opening feature of the invention may be used
 whether or not the package is sealed over the ends of the strands.
 The tear strip to open the film is defined by a heat seal line essentially
 parallel to an edge of the tubular package and is usually from about 0.25
 to about 1.5 inches wide.
 For ease in gripping the tear strip and to provide a quick start for its
 removal, a slit or notch is provided in the packaging film commencing at
 an end of the film and terminating at the heat seal line weakened area.
 The tear strip defined by the heat seal line usually, but not essentially,
 extends the entire length of the strand.
 The invention may be better understood by reference to the preferred
 embodiments illustrated in the drawings which are intended to exemplify
 but not limit the present invention.
 The drawings show a tubular packaging material 10 in the form of a film
 overwrap to hold shirred (radially folded and axially compressed) food
 casing 12. In FIG. 1 the packaging material 10 is shown in a flattened
 form (flat stock). A heat seal joint 14 is formed at a distance of about 1
 mm to about 100 mm from and essentially parallel to a longitudinal edge 16
 of the tubular packaging material 10. The heat seal joint line 14 is
 formed by any suitable means, e.g. a rotary or bar sealer with a sealing
 width that forms a heat seal joint line of from about 0.5 to about 10 mm
 in width and preferably from about to about 1 to about 2 mm in width. The
 heat seal joint line 14 in conjunction with edge 16 defines a tear strip
 17 having a width of from about 1 to about 100 mm and preferably from
 about 1 to about 25 mm. A slit 18 is formed in the tubular packaging
 material 10 which runs from an end 20 of the tubular film to heat seal
 joint line 14 so that pulling of the strip away from the package
 commencing at the slit 18 causes film to separate proximate the heat seal
 joint line thus opening the package. The slit may be formed by any
 suitable means, e.g. scissors or a knife. "Slit" as used herein is
 intended to include other weakened areas along a line, e.g. by a notch or
 by perforations. "Essentially parallel" , as used herein, means that the
 heat seal joint line deviates from being parallel to edge 16 by less than
 15 degrees.
 In using the embodiment shown in FIG. 2, an operator of a food stuffing
 machine can simply load a strand packaged in the tubular film overwrap of
 the invention on a stuffing horn by placing the stuffing horn through bore
 22. The tear strip 17 is then grabbed at the slit 18 and with a quick
 pulling motion pulled free to remove the overwrap.
 In the alternative embodiment shown in FIG. 3, a strand 12 of shirred food
 casing is placed within a tubular package film 10 as above described;
 however, in the alternative embodiment, the tubular package film 10 is
 made in a length that is over twice the length of the strand so that upon
 placement of the strand 12 in the package film 10, a length 21 of package
 film overwrap 10 extending beyond the strand 12 may be inverted and drawn
 through the bore 22 of the strand to form an internal overwrap section
 covering the surface defining a bore 22 through the strand. The ends 20
 and 24 of the tubular film package may then be sealed together by seal 26
 to form an environmentally tight package over the strand. This package may
 then be placed in a carton for storage and shipment without the
 requirement of sealing the carton against the atmosphere or providing
 internal carton moisture.
 In using the overwrap package described in the alternative embodiment, the
 package containing strand 12 is placed over a stuffing horn so that the
 internal overwrap section is located between the stuffing horn and an
 internal surface of the bore 22 of the strand. Before or after placement
 on the stuffing horn, the sea 26 is cut off. The tear strip 17 is then
 pulled along the strand 12. When the exterior portion of the overwrap is
 removed, pulling of the tear strip 17 is continued to cause tearing along
 the interior portion of the overwrap until the entire package is removed.
 This embodiment is unique in that it permits a strand to remain completely
 packaged until seconds before use.