CORELESS FLEXIBLE FILM PACKAGING SYSTEM AND CORELESS CONTAINMENT PACKAGE THEREFOR

Abstract

A coreless flexible film packaging system is disclosed. The system includes: (i) a containment cylinder including a cylindrical wall defining first and second cylinder end apertures and an interior film containment area; (ii) a film feed slot in the cylindrical wall extending longitudinally along the containment cylinder; and (iii) a supply of flexible film wound about itself to form a film roll having a central cylindrical cavity, said roll including a leading end and a terminal end and contained within the interior film containment area. A coreless containment package and a method for packaging a flexible film are also described.

Claims

1. A coreless flexible film packaging system, said system comprising: (i) a containment cylinder comprising a cylindrical wall with an outer surface, said cylindrical wall defining first and second cylinder end apertures and an interior film containment area; (ii) a film feed slot in said cylindrical wall extending longitudinally along said containment cylinder; and (iii) a supply of flexible film wound about itself to form a film roll having a central cylindrical cavity, said film roll comprising a leading end and a terminal end and contained within said interior film containment area.

2. The coreless flexible film packaging system of claim 1 wherein said flexible film is self-winding.

3. The coreless flexible film packaging system of claim 1 wherein said central cylindrical cavity is lined by said film.

4. The coreless flexible film packaging system of claim 1 further comprising a seal strip affixed to said containment cylinder at said outer surface.

5. The coreless flexible film packaging system of claim 4 wherein said seal strip is adjacent to said film feed slot.

6. The coreless flexible film packaging system of claim 4 wherein said terminal end of said supply of said flexible film is affixed to said seal strip.

7. The coreless flexible film packaging system of claim 1 further comprising caps at each of said first and second end apertures.

8. The coreless flexible film packaging system of claim 7 wherein at least one if said caps is substantially transparent.

9. A coreless containment package for containing a supply of flexible film comprising a leading end and a terminal end and wound about itself to form a film roll having a central cylindrical cavity, said package comprising: (i) a containment cylinder for containing said film roll, said cylinder comprising a cylindrical wall with an outer surface, said cylindrical wall defining first and second cylinder end apertures; and (ii) a film feed slot in said cylindrical wall extending longitudinally along said containment cylinder.

10. The coreless containment package of claim 9 further comprising a seal strip affixed to said containment cylinder at said outer surface.

11. The coreless containment package of claim 10 wherein said seal strip is adjacent to said film feed slot.

12. The coreless containment package of claim 10 wherein said terminal end of said supply of said flexible film is affixed to said seal strip.

13. The coreless containment package of claim 9 further comprising caps at each of said first and second end apertures.

14. The coreless containment package of claim 13 wherein at least one of said caps is substantially transparent.

15. The coreless containment package of claim 9 wherein said central cylindrical cavity is lined by said film.

16. A method for packaging a flexible film, said method comprising: (i) providing a containment cylinder, said cylinder comprising a cylindrical wall with an outer surface and a film feed slot in said cylindrical wall extending longitudinally along said containment cylinder, said cylindrical wall defining first and second cylinder end apertures and an interior film containment area; (ii) feeding said flexible film into said interior film containment area through said film feed slot; and (iii) winding said flexible film about itself to form a roll having a central cylindrical cavity lined by said film, said roll contained within said interior film containment area.

17. The method of claim 16 wherein said winding step includes (a) removably inserting a rotating perforated axle into said interior film containment area; and (b) removably attaching said leading end of said flexible film to said axle.

18. The method of claim 17 wherein said removably attaching step (b) includes applying vacuum to said flexible film.

19. The method of claim 17 further comprising releasing said vacuum and optionally applying pressure to said flexible film at the conclusion of said winding step.

20. The method of claim 17 further comprising removing said perforated axle from said interior film containment area at the conclusion of said winding step.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0015] FIG. 1 is a side elevational view of an embodiment of the coreless flexible film packaging system of the present invention, with the packaged flexible film shown partially outside the containment cylinder for illustration purposes only.

[0016] FIG. 2 is partial side elevational view of an embodiment of the coreless flexible film packaging system of the present invention, with the packaged flexible film shown partially outside the containment cylinder for illustration purposes only.

[0017] FIG. 3 is a partial side elevational view of an embodiment of the coreless containment package of the present invention.

[0018] FIG. 4 is a side elevational view of an embodiment of the coreless containment package of the present invention that includes caps.

[0019] FIG. 5 is a partial side elevational view illustrating suitable equipment for practicing the method of the present invention for packaging a flexible film.

DETAILED DESCRIPTION

[0020] As shown in FIGS. 1 and 2, a first aspect of the present invention is directed to a coreless containment package 10 for containing a supply of flexible film 15. The film 15 includes a leading end 18 and a terminal end 19 and is wound about itself to form a film roll 20 which includes a central cylindrical cavity 25 that is preferably lined by film 15. The coreless containment package 10 includes containment cylinder 30 for containing the film roll 20. The cylinder 30 includes cylindrical wall 35 having an outer surface 40, with cylindrical wall 35 defining first and second cylinder end apertures 45 and 50. Containment package 10 further includes a film feed slot 55 in said cylindrical wall 35 extending longitudinally along the containment cylinder 30. Containment cylinder 30 may be formed from materials well known to one of ordinary skill, for example cardboard or plastics such as polypropylene or polystyrene, using well-known manufacturing techniques selected depending in part on the material chosen, such as for example injection molding or hot melt extrusion when the core is formed from plastic. The term “coreless” is utilized herein to denote that the film is wound about itself to form a film roll which includes a central cylindrical cavity lined by film as opposed to packaging in which the film roll is wound onto a cylindrical supporting carrier or core.

[0021] As shown in FIGS. 3 and 4, the coreless containment package 10 of the present invention preferably further includes seal strip 57 affixed to said containment cylinder 30 at said outer surface 40. Preferably the seal strip 57 is located adjacent to film feed slot 55 and most preferably is also affixed to the terminal end 19 of the supply of said flexible film 15. Seal strip 57 may be applied to the core and formed in situ from materials well known to one of ordinary skill, for example a pressure sensitive, hot melt or curable adhesive. Seal strip 57 may also be a separately formed adhesive tape adhered to the core.

[0022] In a particularly preferred embodiment, the coreless containment package 10 further includes caps 60 at each of said first and second end apertures 45 and 50. Caps 60 may be formed from materials well known to one of ordinary skill, for example thermoplastic polymers, using well-known manufacturing techniques such as for example injection molding and hot-press molding. In this embodiment, the outer surface 40 of the cylindrical wall 35 of the cylinder constitutes the exposed surface of a coreless flexible film packaging system as described below. In comparison to the prior art flexible film packaging systems wherein film wound on a core formed from rigid, non-compressible plastic, cardboard or the like which is then contained in a box, bag or other packaging to protect the film, this embodiment of the present invention provides an advantageous, environmentally friendly and cost-saving alternative system that uses significantly less packaging material and accordingly reduced packaging waste. In this embodiment, at least one of the caps 60 is substantially transparent so as to facilitate visual inspection of the film. Outer surface 40 may also optionally include at least one of printing or graphics so as to provide information and/or an aesthetically pleasing appearance to customers.

[0023] In a second and related aspect, the present invention relates to a coreless flexible film packaging system. In its most general sense and as shown in FIGS. 1-4, the coreless flexible film packaging system 75 of the present invention includes flexible film 15 contained within coreless containment package 10. Accordingly, the coreless flexible film packaging system 75 includes: (i) a containment cylinder 30 that includes cylindrical wall 35 having an outer surface 40, with cylindrical wall 35 defining first and second cylinder end apertures 45 and 50 and an interior film containment area 52; (ii) a film feed slot 55 in said cylindrical wall 35 extending longitudinally along said containment cylinder 30; and (iii) a supply of flexible film 15 wound about itself to form a film roll 20 having a central cylindrical cavity 25 lined by film 15. Film 15 further includes a leading end 18 and terminal end 19 and is contained within said interior film containment area 52. Containment cylinder 30 may be formed from materials well known to one of ordinary skill, for example cardboard or plastics such as polypropylene and made using well-known manufacturing techniques selected depending in part on the material chosen, such as for example injection molding or hot melt extrusion when the core is formed from plastic.

[0024] The system 75 preferably further includes seal strip 57 affixed to said containment cylinder 30 at said outer surface 40. Preferably the seal strip 57 is located adjacent to film feed slot 55 and most preferably is also affixed to the terminal end 19 of the supply of said flexible film 15. Seal strip 57 may be applied to the core and formed in situ from materials well known to one of ordinary skill, for example a pressure sensitive, hot melt or curable adhesive composition. Seal strip 57 may also be a separately formed adhesive tape adhered to the core.

[0025] In a particularly preferred embodiment, the system 75 further includes caps 60 at each of said first and second end apertures 45 and 50. Caps 60 may be formed from materials well known to one of ordinary skill, for example thermoplastic polymers, using well-known manufacturing techniques such as for example injection molding and extrusion. In this embodiment, the outer surface 40 of the cylindrical wall 35 of the cylinder constitutes the exposed surface 80 of the coreless flexible film packaging system. In comparison to the prior art flexible film packaging systems wherein film is wound on a core which is then enclosed in a box, bag or other packaging to protect the film, the system 75 provides an advantageous, environmentally friendly and cost-saving alternative that uses significantly less packaging material and accordingly reduces the amount of packaging waste. Further, it will be readily appreciated that the film feed slot of the system is also a dispensing port for the contained flexible film in this embodiment.

[0026] In this embodiment, at least one of the caps 60 is substantially transparent so as to facilitate visual inspection of the film. Exposed surface 80 may also optionally include at least one of printing or graphics so as to provide information and/or an aesthetically pleasing appearance to customers.

[0027] The flexible film for use with the present invention may be any flexible film, web or the like typically packaged concurrent with or after manufacturing as a roll. Non-limiting examples include PET, polypropylene, PVC, polyurethane and the like. Preferably, the flexible film is “self-winding”, defined herein to encompass films that exhibit a natural tendency to wind or curl about themselves without application of external force. For example, many films utilized in the window films industry develop during manufacture what is known in the art as “MD (machine direction) curl”, a tendency of the film to curl in the direction in which the film travels during process operations such as dyeing, coating, laminating and slitting. This tendency can be particularly relevant in flexible films with multiple laminated layers or applied coatings and is created as tension that is applied during the processing steps elongates the film and creates strain in the layers that varies for example by layer type and thickness. For example, MD curl in commercial window film constructions generally towards the scratch-resistant coating.

[0028] In a third aspect, the present invention relates to a method for packaging a flexible film. The method of the present invention includes: (i) providing a containment cylinder that includes a cylindrical wall with an outer surface and a longitudinally extending film feed slot, with the cylindrical wall defining first and second cylinder end apertures and an interior film containment area; (ii) feeding the flexible film into the interior film containment area through the film feed slot; and (iii) winding said flexible film about itself to form a roll having a central cylindrical cavity lined by said film, with the roll contained within the interior film containment area.

[0029] Suitable equipment for operation of the method of the present invention is shown in FIG. 5. With regard to the in-feed step, film may be fed into the film containment area of the containment cylinder by means of a feed device such as a driven nip roller 65 in relatively close proximity to the film feed slot 55. The containment cylinder is preferably held stationary in position during the feeding step. It will be understood by one of ordinary skill that a number of variables, such as for example the feed velocity and feed angle of the film on entry into the containment cylinder, through the feed slot and the distance between the nip and the feed slot may be adjusted to optimize winding performance. It is anticipated that film angled towards the top inside surface of the core and the shortest distance from the nip to core entrance slot will provide better winding.

[0030] Preferably, the flexible film is a self-winding film which winds about itself to form the roll without externally applied force and the winding step therefore includes self-winding of the flexible film. For example, in the embodiment where the flexible film is a window film that includes a scratch-resistant coating, winding would include self-winding of the flexible film toward the scratch resistant side. In typical window film constructions, this will leave a release liner side, a more slippery surface, to slide against the inside surface of the cylinder during winding.

[0031] Optionally, the winding step may include applying external winding force to the film. In one particular embodiment, the optional winding force is applied by a rotatable axle 85 such that the winding step of the method present invention includes (a) removably inserting a rotating axle 85 into the interior film containment area 52 and (b) removably attaching said leading end 18 of flexible film 15 to the axle 85. In this embodiment, the method of the present invention most preferably includes the further step (c) of releasing the leading end of the film from the axle at the conclusion of said winding step and removing the rotating axle from interior film containment area. In a particularly preferred embodiment, rotating axle 85 is a perforated axle connected to a vacuum/pressure source such that the removably attaching step (b) above preferably includes applying vacuum to the flexible film during winding and the releasing step (c) preferably includes releasing the vacuum when winding is complete. The releasing step (c) may optionally also include applying positive pressure to the flexible film to facilitate release of the leading end of the flexible film 15 at the conclusion of the winding step when winding is complete. Axle 85 and the nip roller speed should be controlled and adjusted so that the flexible film 15 does not wind up around the axle 85 but is simply held by it at and close to the leading end 18.

[0032] As movement of materials such as flexible films can cause static build up, it will be understood that the method of the present invention preferably includes electrically grounding the flexible film and the containment cylinder.

[0033] The foregoing description of various embodiments of the invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise embodiments disclosed. Numerous modifications or variations are possible in light of the above teachings. The embodiments discussed were chosen and described to provide the best illustration of the principles of the invention and its practical application to thereby enable one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the invention as determined by the appended claims when interpreted in accordance with the breadth to which they are fairly, legally, and equitably entitled.