FIELD OF THE INVENTION
[0001] The present invention relates to packaged flexible polymer films and packaging systems
for flexible polymer films.
BACKGROUND OF THE INVENTION
[0002] In the prior art, flexible films formed from polymeric materials and/or plastics
are typically packaged at the manufacturing site as rolls, with the film wound onto
a cylindrical supporting carrier formed from rigid, non-compressible plastic, cardboard
or the like (called a core). The roll is then enclosed and contained in a box, bag
or other packaging to protect the film during transport and provide an aesthetically
pleasing appearance to customers. For some products, for example films for application
to windows installed in automobiles and buildings, the flexible films are often packaged
during manufacture in large and heavy "bulk" rolls; however, product distribution
channel requirements demand that film wound on such bulk rolls be unwound and then
rewound into smaller "commercial" rolls for shipping and eventual sale. By way of
example, such window films are often wound on bulk rolls of around 3000 meters at
manufacture and then repackaged for sale to customers in relatively short rolls wherein
30.5 meters or less of material is wound on a 76.5mm diameter plastic core. Highly
specialized flexible films, such as metallized films for use in medical testing devices,
electronic devices, displays and the like, are also packaged as rolls of material
wound on a core.
[0003] So that the film can be wound onto the core properly for commercial rolls, the leading
end of the film nearest the core is typically adhered to the core using a double-sided
self-adhesive strip that runs transversely along the full width of the film at the
leading end. When the film is unwound from the commercial roll for use, the 1-3 meters
of the film packaged nearest the core when originally wound thereon, is often found
to be unusable as a result of a repeating imprint, sometimes referred to as an "embossment",
created in the initial wraps of the film around the core. Because the flexible film
is relatively thin, in the order of 60 - 400µ, this imprint effect is replicated in
several of the innermost layers of wound film close to the core. These imprints are
caused by one or more factors typically present in the packaging process and system.
There are several reasons why film suffers from imprints. These include:
Film tension. Mechanical requirements demand that tension is applied during winding in order to
be able to process film through the winding machine.
Film Edge. The leading end of the film runs across the width of the wound film and is cut with
a relatively sharp vertical edge that forms a ridge at the interface of the film's
leading end with surface of the core.
Adhesive Strip. The double sided adhesive strip has a minimized (typically 25-50µ) but nonetheless
potentially impactful thickness and can create an even more severe imprint than the
end of the film. It presents two ends rather than one and the general evenness of
the thickness of adhesive strip over the entire area of adhesive, particularly hand-applied
aerosol pressure sensitive adhesives, can be very poor.
Core surface. The core surface itself may have defects or minute contaminants that impact its
uniformity and smoothness.
[0004] These imprints are typically permanent such that, if use of the film is attempted,
defects in the final product's functionality and/or aesthetic appearance are highly
likely. With respect to window films, installation of this portion of the film from
the roll on a vehicle or building window is often the source for consumer complaints
and warranty claims.
[0005] One prior art attempt to overcome the embossment problem included chamfering the
leading end of the film so that the cut end of the film is angled or gradually reduced
in thickness rather than presenting a sharp vertical end. It is difficult with such
thin materials, however, to achieve any uniform angled cut of this kind, particularly
at such a shallow angle as would be necessary to materially reduce the impact of the
leading end on the imprint problem. Other prior art methods to reduce imprinting involve
changing aspects of the core, for example (i) milling an angled depression into the
length of the core such that the leading end of the film seats in the depression in
the core so as to present a smooth surface over which subsequent layers of film wrap
during winding onto the core or (ii) modifying the core to include a slit or other
feature to "trap" and/or hold the leading end of the film within the core cavity.
Such solutions are, however, typically not cost effective as they add expensive machining,
molding, slitting or other high-precision steps to the core manufacturing process
and create the need for cores that are highly customized to match individual film
types and thicknesses. Further, they also present challenges in properly adhering
the leading end of the film to the core so that the roll can be properly wound.
[0006] Despite these prior art efforts, embossments remain a significant source of waste
and inefficiency for the flexible films industry. Aside and apart from the embossment
problem, the films industry is in lock step with industry in general as it seeks out
improved, sustainable packaging systems and for its products that reduce excess packaging
material and waste.
[0007] The prior art document
DE 93 00 693 U1 describes a container for receiving a pack of bags tearably connected to each other
and which can be carried in a handbag. The container is formed by a piece of pipe
at whose end faces one end wall is detachably connected to the pipe section for filling
the container. The pipe section having a withdrawal slot running along a circumferential
line for pulling out the pipe section.
[0008] The
GB 2 472 436 A describes portable bag dispenser comprising a roll of bags contained in a cartridge
inside the container. The container is formed from two sections that can be joined
together and separated. When the container is joined together it encloses the cartridge
and when it is separated the cartridge can be removed.
[0009] The
EP 1 352 602 A2 describes a package for dispensing a paper roll, comprising a rotatable paper roll
and a housing in which the paper roll is contained. The housing forms a dispenser
for the paper roll having an opening provided in the housing and a fastener for attaching
the package to a wall.
[0010] The
US 4 771 889 A describes a packaged food casing article having a rotatable support to support e.g.
paper rol.
[0011] The
GB 934 550 A describes forming a package of biscuits which comprises applying wrapping material
about an end of a continuous column of biscuits.
[0012] The
EP 2 017 2015 A1 describes a method of manufacturing a roll that unwinds from the centre by forming
a protrusion along a length axis of one of side of the roll.
SUMMARY OF THE INVENTION
[0013] In a first aspect, the present invention relates to a coreless flexible film packaging
system. 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, with the roll comprising a leading
end and a terminal end and contained within said interior film containment area, and
wherein said flexible film is self-winding.
[0014] In yet another aspect, the present invention relates to a method for packaging a
flexible film including: (i) providing a containment cylinder, the cylinder including
a cylindrical wall and a film feed slot extending longitudinally along the containment
cylinder, 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 film roll having a central cylindrical cavity lined by
the film, with roll contained within the interior film containment area, wherein said
film is self-winding.
[0015] Further aspects of the invention are as disclosed and claimed herein.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016]
Figure 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.
Figure 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.
Figure 3 is a partial side elevational view of an embodiment of the coreless containment
package of the present invention.
Figure 4 is a side elevational view of an embodiment of the coreless containment package
of the present invention that includes caps.
Figure 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
[0017] 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.
[0018] The present invention relates to a coreless flexible film packaging system. In its
most general sense and as shown in Figures 1-4. 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.
[0019] 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.
[0020] 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.
[0021] 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.
[0022] 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. 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.
[0023] 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, wherein said
fil 15 is self-winding.
[0024] Suitable equipment for operation of the method of the present invention is shown
in Figure 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.
[0025] 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 includes 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.
[0026] 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 end18.
[0027] 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.
[0028] 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.
1. A coreless flexible film packaging system (75), said system comprising:
(i) a containment cylinder (30) comprising a cylindrical wall (35) with an outer surface
(40), said cylindrical wall (35) defining first and second cylinder end apertures
(45, 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), said film roll (20) comprising a leading end and
a terminal end and contained within said interior film containment area (52),
characterized in that,
said flexible film (15) is self-winding.
2. The coreless flexible film packaging system of claim 1 wherein said central cylindrical
cavity (25) is lined by said film (15).
3. The coreless flexible film packaging system of claim 1 further comprising a seal strip
(57) affixed to said containment cylinder (30) at said outer surface (40).
4. The coreless flexible film packaging system of claim 3 wherein said seal strip (57)
is adjacent to said film feed slot (55).
5. The coreless flexible film packaging system of claim 3 wherein said terminal end of
said supply of said flexible film (15) is affixed to said seal strip (57).
6. The coreless flexible film packaging system of claim 1 further comprising caps (60)
at each of said first and second end apertures (45, 50).
7. The coreless flexible film packaging system of claim 6 wherein at least one if said
caps (60) is substantially transparent.
8. A method for packaging a flexible film, said method comprising:
(i) providing a containment cylinder (30), said cylinder (30) comprising a cylindrical
wall (35) with an outer surface (40) and a film feed slot (55) in said cylindrical
wall (35) extending longitudinally along said containment cylinder(30), said cylindrical
wall (35) defining first and second cylinder end apertures (45, 50) and an interior
film containment area (52);
(ii) feeding said flexible film (15) into said interior film containment area (52)
through said film feed slot (55); and
(iii) winding said flexible film (15) about itself to form a roll having a central
cylindrical cavity (25) lined by said film (15), said roll contained within said interior
film containment area (52), wherein said film (15) is self-winding.
9. The method of claim 8 wherein said winding step includes
(a) removably inserting a rotating perforated axle (85) into said interior film containment
area (52); and
(b) removably attaching said leading end of said flexible film (15) to said axle (85).
10. The method of claim 9 wherein said removably attaching step (b) includes applying
vacuum to said flexible film (15).
11. The method of claim 9 further comprising releasing said vacuum and optionally applying
pressure to said flexible film (15) at the conclusion of said winding step.
12. The method of claim 9 further comprising removing said perforated axle (85) from said
interior film containment area (52) at the conclusion of said winding step.
1. Kernloses flexibles Folienverpackungssystem (75), das System aufweisend:
(i) einen Aufnahmezylinder (30), der eine zylindrische Wand (35) mit einer Außenfläche
(40) umfasst, wobei die zylindrische Wand (35) eine erste und eine zweite Zylinderendöffnung
(45, 50) und einen inneren Folienaufnahmebereich (52) definiert;
(ii) einen Folienzuführschlitz (55) in der zylindrischen Wand (35), der sich in Längsrichtung
entlang des Aufnahmezylinders (30) erstreckt; und
(iii) einen Vorrat an flexibler Folie (15), die um sich selbst gewickelt ist, um eine
Folienrolle (20) mit einem zentralen zylindrischen Hohlraum (25) zu bilden, wobei
die Folienrolle (20) ein vorderes Ende und ein hinteres Ende aufweist und in dem inneren
Folienaufnahmebereich (52) enthalten ist,
dadurch gekennzeichnet, dass
die flexible Folie (15) selbstaufwickelnd ist.
2. Kernloses flexibles Folienverpackungssystem nach Anspruch 1, bei dem der zentrale
zylindrische Hohlraum (25) mit der Folie (15) ausgekleidet ist.
3. Kernloses flexibles Folienverpackungssystem nach Anspruch 1 ferner aufweisend einen
Dichtungsstreifen (57), der an der Außenfläche (40) des Aufnahmezylinders (30) befestigt
ist.
4. Kernloses flexibles Folienverpackungssystem nach Anspruch 3, bei dem sich der Dichtungsstreifen
(57) neben dem Folienzuführschlitz (55) befindet.
5. Kernloses flexibles Folienverpackungssystem nach Anspruch 3, wobei das hintere Ende
des Vorrats an flexibler Folie (15) an dem Dichtungsstreifen (57) befestigt ist.
6. Kernloses flexible Folienverpackungssystem nach Anspruch 1 ferner aufweisend Kappen
(60) an jeder der ersten und zweiten Endöffnungen (45, 50).
7. Kernloses flexibles Folienverpackungssystem nach Anspruch 6, wobei mindestens eine
der Kappen (60) im Wesentlichen transparent ist.
8. Verfahren zum Verpacken einer flexiblen Folie, das Verfahren aufweisend:
(i) Bereitstellen eines Aufnahmezylinders (30), wobei der Zylinder (30) eine zylindrische
Wand (35) mit einer Außenfläche (40) und einem Folienzuführschlitz (55) in der zylindrischen
Wand (35) aufweist, der sich in Längsrichtung entlang des Aufnahmezylinders (30) erstreckt,
wobei die zylindrische Wand (35) eine erste und eine zweite Zylinderendöffnung (45,
50) und einen inneren Folienaufnahmebereich (52) definiert;
(ii) Zuführen der flexiblen Folie (15) in den inneren Folienaufnahmebereich (52) durch
den Folienzuführschlitz (55); und
(iii) Aufwickeln der flexiblen Folie (15) um sich selbst, um eine Rolle mit einem
zentralen zylindrischen Hohlraum (25) zu bilden, der von der Folie (15) ausgekleidet
ist, wobei die Rolle in dem inneren Folienaufnahmebereich (52) enthalten ist, wobei
die Folie (15) selbstaufwickelnd ist.
9. Verfahren nach Anspruch 8, wobei der Aufwickelschritt beinhaltet
(a) entfernbares Einsetzen einer rotierenden perforierten Achse (85) in den inneren
Folienaufnahmebereich (52); und
(b) entfernbares Anbringen des vorderen Endes der flexiblen Folie (15) an der Achse
(85).
10. Verfahren nach Anspruch 9, wobei der Schritt (b) des entfernbaren Anbringens das Anlegen
eines Vakuums an die flexible Folie (15) beinhaltet.
11. Verfahren nach Anspruch 9 ferner aufweisend das Abbauen des Vakuums und gegebenenfalls
das Aufbringen von Druck auf die flexible Folie (15) nach Abschluss des Aufwickelschritts.
12. Das Verfahren nach Anspruch 9 ferner aufweisend das Entfernen der perforierten Achse
(85) aus dem inneren Folienaufnahmebereich (52) nach Abschluss des Aufwickelschritts.
1. Système d'emballage de film souple sans mandrin (75), ledit système comprenant :
(i) un cylindre de confinement (30) comprenant une paroi cylindrique (35) avec une
surface externe (40), ladite paroi cylindrique (35) définissant des première et deuxième
ouvertures d'extrémité de cylindre (45, 50) et une zone intérieure de confinement
de film (52) ;
(ii) une fente d'alimentation de film (55) dans ladite paroi cylindrique (35) s'étendant
longitudinalement le long dudit cylindre de confinement (30) ; et
(iii) un stock de film souple (15) enroulé sur lui-même afin de former un rouleau
de film (20) ayant une cavité centrale cylindrique (25), ledit rouleau de film (20)
comprenant une extrémité de tête et une extrémité terminale et étant contenu à l'intérieur
de ladite zone intérieure de confinement de film (52),
caractérisé en ce que,
ledit film souple (15) est auto-enroulable.
2. Système d'emballage de film souple sans mandrin selon la revendication 1 dans lequel
ladite cavité centrale cylindrique (25) est doublée par ledit film (15).
3. Système d'emballage de film souple sans mandrin selon la revendication 1 comprenant
en outre une bande de scellement (57) apposée sur ledit cylindre de confinement (30)
au niveau de ladite surface externe (40).
4. Système d'emballage de film souple sans mandrin selon la revendication 3 dans lequel
ladite bande de scellement (57) est adjacente à ladite fente d'alimentation de film
(55).
5. Système d'emballage de film souple sans mandrin selon la revendication 3 dans lequel
ladite extrémité terminale dudit stock dudit film souple (15) est apposée sur ladite
bande de scellement (57).
6. Système d'emballage de film souple sans mandrin selon la revendication 1 comprenant
en outre des bouchons (60) au niveau de chacune desdites première et deuxième ouvertures
d'extrémité (45, 50).
7. Système d'emballage de film souple sans mandrin selon la revendication 6 dans lequel
au moins un desdits bouchons (60) est sensiblement transparent.
8. Procédé pour l'emballage d'un film souple, ledit procédé comprenant :
(i) la fourniture d'un cylindre de confinement (30), ledit cylindre (30) comprenant
une paroi cylindrique (35) avec une surface externe (40) et une fente d'alimentation
de film (55) dans ladite paroi cylindrique (55) s'étendant longitudinalement le long
dudit cylindre de confinement (30), ladite paroi cylindrique (35) définissant des
première et deuxième ouvertures d'extrémité de cylindre (45, 50) et une zone intérieure
de confinement de film (52) ;
(ii) l'alimentation dudit film souple (15) dans ladite zone intérieure de confinement
de film (52) à travers ladite fente d'alimentation de film (55) ; et
(iii) l'enroulement dudit film souple (15) autour de lui-même afin de former un rouleau
ayant une cavité centrale cylindrique (25) doublée par ledit film (15), ledit rouleau
étant contenu à l'intérieur de ladite zone intérieure de confinement de film (52),
dans lequel ledit film (15) est auto-enroulable.
9. Procédé selon la revendication 8 dans lequel ladite étape d'enroulement inclut
(a) l'insertion de manière amovible d'un axe rotatif perforé (85) dans ladite zone
intérieure de confinement de film (52) ; et
(b) la fixation de manière amovible de ladite extrémité de tête dudit film souple
(15) audit axe (85).
10. Procédé selon la revendication 9 dans lequel ladite étape (b) de fixation amovible
inclut l'application de vide audit film souple (15).
11. Procédé selon la revendication 9 comprenant en outre la libération dudit vide et éventuellement
l'application d'une pression audit film souple (15) à la fin de ladite étape d'enroulement.
12. Procédé selon la revendication 9 comprenant en outre l'enlèvement dudit axe perforé
(85) de ladite zone intérieure de confinement de film (52) à la fin de ladite étape
d'enroulement.