Wrapped material, and method and apparatus for wrapping and unwrapping such material

An elongate mass of material wrapped by a liner in which the liner is wrapped around the material with the liner inside surface facing the peripheral surface of the material, with first and second regions of the liner extending away from the material with the liner inside surface of the first region in unbonded contact with the liner inside surface of the second region so as to enclose the material with said liner. The material and the center region of the liner together form a core of the wrapped mass of material, and the first and second liner regions together form a tab of the wrapped mass of material. The wrapped mass of material includes a first portion and a second portion and is arranged such that the core of a second portion applies sufficient force to the tab of a first portion so as to maintain the mass of material enveloped by the liner at the first portion. Also presented are methods and apparatus for wrapping and unwrapping such material. A preferred embodiment of the invention provides a cold-flowable material such as a hot-melt pressure sensitive adhesive wrapped in a liner such that the liner is easily removed from the material.

TECHNICAL FIELD 
The present invention relates generally to a wrapped mass of material and 
to methods and apparatus for wrapping and unwrapping such material. The 
present invention relates more particularly to a cold-flowable material 
such as a hot-melt pressure sensitive adhesive wrapped in a liner such 
that the liner is easily removed from the material, and a method and 
apparatus for wrapping and unwrapping the material with the liner. 
BACKGROUND OF THE INVENTION 
There have been several attempts to provide a means to package and handle 
materials such a hot melt pressure sensitive adhesives. For example, U.S. 
Pat. No. 5,392,592, "Hot-Melt Pressure Sensitive Adhesive Packaging, 
Preform, and Method," (Bozich et al.), describes a method for waste-free 
packaging for a hot-melt pressure sensitive adhesive that comprises 
extruding a hot-melt pressure sensitive adhesive into a continuous tubular 
film, wherein the film is compatible with being integrated into the 
composition of the hot-melt adhesive composition. In one embodiment, the 
preform of the packaging material of Bozich et al. comprises a continuous 
sheet of a heat sealable film having two opposed edges, with a patterned 
silicone coating on at least one face leaving an uncoated area. The 
uncoated area on the first edge is capable of forming a heat seal with a 
second uncoated area on either face in proximity to the opposite edge. The 
heat sealable film must be capable of being sealed by the application of 
heat or a hot-melt adhesive. Hot melt adhesive is then extruded into the 
tubular film and the tube is crimped to isolate desired amounts of 
adhesive between crimps. By melting the compatibly packaged hot melt 
adhesive in a glue pot, the compatible packaging becomes compatibly 
integrated into the molten hot melt adhesive composition. 
U.S. Pat. No. 5,373,682, "Method for Tackless Packaging of Hot Melt 
Adhesives," (Hatfield et al.), discusses packaging a non-blocking hot-melt 
adhesive by directly pouring or pumping the molten adhesive into a 
cylindrical plastic tube, the tube being in contact with a heat sink. The 
tube comprises a thermoplastic film which is meltable together with the 
adhesive composition and blendable into the molten adhesive and which will 
not deleteriously affect the properties of the adhesive composition when 
blended therewith. In one embodiment, the plastic film is threaded through 
a film folder which folds the film and forms a lap seal around a fill pipe 
or mandrel. The lap seal is sealed with hot air, induction welding or 
ultrasonic welding. The molten hot-melt adhesive is then pumped into the 
tube. The adhesive filled tube is then crimped or pinched into smaller 
cartridge size segments. 
U.S. Pat. No. 3,418,059, "Dispenser Package for Flowable Materials and 
Method of Forming Same," (Robe), discusses a dispenser package in the form 
of a flexible pouch having a constricted throat orifice separating the 
main portion of the pouch from a dispenser portion. A method is provided 
for forming the pouch by forming a tube of a thermoplastic material, and 
using a heat sealing device to form the material into a tube, then 
gathering the tube material at spaced locations and applying heat to form 
a thickened, stiffened portion at the throat orifice. 
U.K. Patent Application GB 2,135,238A, "Producing Tubes for Packages," 
discusses a tube for packaging in which a mandrel is used to provide a 
tubular packaging means having a longitudinal seam formed as a sealed 
film. This application also discusses a method of producing tubular 
packaging means from a flat length of film, in particular heat sealable 
film, which comprises folding a length of film about a sealing mandrel to 
bring two longitudinal edges of the film against each other alongside the 
sealing mandrel, sealing the two edges to form a sealed film, and drawing 
the tubular piece off the sealing mandrel. 
U.S. Pat. No. 4,755,245, "Method for Conditioning a Permanent Adhesive 
Composition in the Form of Blocks or Sections," (Viel), discusses several 
prior proposed and implemented methods to package adhesive compositions. 
The methods discussed in Viel include providing permanent adhesive 
compositions in the form of rods, blocks, strips, sections, and slabs, 
which are enveloped by a thin film. Viel characterizes the method of 
wrapping with film as costly. Veil also points out that the choice of 
films suitable for such protection is fairly limited since it is 
absolutely essential that they blend perfectly with the composition during 
re-melting of the latter when used, as the protected composition is now 
inseparable from its protective film. 
It is also known to provide hot melt adhesives in the form of a coextruded 
core/sheath composite, in which the sheath is relatively non-tacky and can 
be mixed with the material of the core upon remelt of the composite. It is 
also known that such composites can be coiled about a spool. See, for 
example, U.S. Pat. Nos. 3,317,368 and 4,490,424, and U.K. Patent 
Specification 1,095,735. 
SUMMARY OF THE INVENTION 
The present invention provides generally a wrapped mass of material and 
methods and apparatus for wrapping and unwrapping such material. A 
preferred embodiment of the invention provides a cold-flowable material 
such as a hot-melt pressure sensitive adhesive wrapped in a liner such 
that the liner is easily removed from the material. The present invention 
also provides a method and apparatus for wrapping and unwrapping the 
material with the liner. The present invention is also useful for wrapping 
difficult to handle materials, such as materials which stick or bond to 
themselves. The present invention is also useful with materials which are 
not coherent or strong enough to be drawn through processing or delivery 
apparatuses themselves, but which can be easily packaged and handled 
according to the present invention by drawing the liner which wraps the 
material. This can include materials in particulate form. 
One aspect of the present invention presents a wrapped mass of material. 
The wrapped mass of material comprises an elongate mass of material 
including an outer peripheral surface and a liner. The liner includes an 
inside surface, an outside surface, a first edge, and a second edge, with 
the first and second edges opposite to one another. The liner also 
includes a first region extending along the first edge, a second region 
extending along the second edge, and a center region between the first and 
second regions. The liner is wrapped around the mass of material with the 
liner inside surface at the center region facing the peripheral surface of 
the mass of material, the liner first and second regions extending away 
from the mass of material with the liner inside surface of the first 
region contacting the liner inside surface of the second region so as to 
enclose the mass of material within the liner. The mass of material and 
the center region of the liner together form a core of the wrapped mass of 
material, and the first region and the second region together form a tab 
of the wrapped mass of material. The wrapped mass of material includes a 
first portion and a second portion and is arranged such that the tab of 
the first portion and the core of the second portion contact one another 
so as to maintain the mass of material enveloped by the liner at the first 
region. 
In one preferred embodiment of the above wrapped mass of material, the mass 
of material comprises a cold-flowable material. In one aspect of this 
embodiment, the cold-flowable material is subject to cold flow at 
20.degree. C. In another aspect of this embodiment, the liner inside 
surface of the first region is in unbonded contact with the liner inside 
surface of the second region. In another preferred embodiment, the 
cold-flowable material comprises a hot-melt pressure sensitive adhesive. 
In another preferred embodiment of the above wrapped mass of material, the 
liner comprises a polyethylene liner including a silicone release coating 
on at least the inside surface. In still another preferred embodiment, the 
liner comprises a cloth including a silicone release coating on at least 
the inside surface. 
In another preferred embodiment of the above wrapped mass of material, the 
first and second portions of the wrapped mass of material are portions of 
a continuous wrapped mass of material. In a variation to this embodiment, 
the first and second portions are of discrete, discontinuous first and 
second respective wrapped masses of materials. In another preferred 
embodiment, the wrapped mass of material is arranged in a coil about a 
spool and the core of each successive coil contacts the tab of each 
respective previous coil. 
The present invention also provides another embodiment of a wrapped mass of 
material. The wrapped mass of material includes an elongate mass of 
cold-flowable material including an outer peripheral surface and a liner. 
The liner includes an inside surface, an outside surface, a first edge, 
and a second edge, with the first and second edges opposite to one 
another. The liner also includes a first region extending along the first 
edge, a second region extending along the second edge, and a center region 
between the first and second regions. The liner is wrapped around the 
cold-flowable material with the liner inside surface at the center region 
facing the peripheral surface of the cold-flowable material, the liner 
first and second regions extending away from the cold-flowable material 
with the liner inside surface of the first region in unbonded contact with 
the liner inside surface of the second region so as to enclose the 
cold-flowable material with the liner. 
The present invention also provides a wrapped cold-flowable material, 
comprising an elongate mass of cold-flowable material including an outer 
peripheral surface and a liner. The liner includes an inside surface, an 
outside surface, a first edge, and a second edge, with the first and 
second edges opposite to one another. The liner also includes a first 
region extending along the first edge, a second region extending along the 
second edge, and a center region between the first and second regions. The 
liner is wrapped around the cold-flowable material with the liner inside 
surface at the center portion facing the peripheral surface of the 
cold-flowable material, the liner first and second regions extending away 
from the cold-flowable material with the liner inside surface of the first 
region in unbonded contact with the liner inside surface of the second 
region so as to enclose the cold-flowable material with the liner. The 
mass of cold-flowable material and the center region of the liner together 
form a core of the wrapped mass of cold-flowable material, and the first 
region and the second region together form a tab of the wrapped mass of 
cold-flowable material. The wrapped mass of cold-flowable material 
includes a first portion and a second portion and is arranged such that 
the tab of the first portion and the core of the second portion contact 
one another so as to maintain the mass of cold-flowable material enveloped 
by the liner at the first portion. 
The present invention also provides a wrapped hot melt adhesive, comprising 
an elongate mass of cold-flowable hot melt adhesive including an outer 
peripheral surface and a liner. The liner includes an inside surface, an 
outside surface, a first edge, and a second edge, with the first and 
second edges opposite to one another. The liner includes a first region 
extending along the first edge, a second region extending along the second 
edge, and a center region between the first and second regions. The liner 
is wrapped around the hot melt adhesive with the liner inside surface at 
the center region facing the peripheral surface of the hot melt adhesive, 
the liner first and second regions extending away from the hot melt 
adhesive with the liner inside surface of the first region in unbonded 
contact with the liner inside surface of the second region so as to 
enclose the hot melt adhesive with the liner. The mass of material and the 
center region of the liner together form a core of the wrapped mass of hot 
melt adhesive, and the first region and the second region together form a 
tab of the wrapped mass of hot melt adhesive. The wrapped mass of hot melt 
adhesive includes a first portion and a second portion and is arranged 
such that the tab of the first portion and the core of the second contact 
one another so as to maintain the hot melt adhesive enveloped by the liner 
at the first portion. 
The present invention also provides a method of enclosing a mass of 
material with a liner. The method includes the steps of: a) contacting a 
region of an inside surface of an elongate liner with at least a portion 
of the outer peripheral surface of an elongate mass of material, wherein 
the liner has first and second regions on opposite side of the center 
region; b) bringing the first and second regions of the inside surface of 
the liner together so as to enclose the mass of material with the liner, 
thereby forming: (i) a core of wrapped mass of material which includes the 
mass of material and the center region of the liner and (ii) a tab of the 
wrapped mass of material which includes the first and second regions of 
the liner; and c) arranging the wrapped mass of material such that the tab 
of a first portion of the wrapped mass of material and the core of a 
second portion of the wrapped mass of material contact one another so as 
to maintain the mass of material enveloped by the liner at the first 
portion. 
In one preferred embodiment of the above method, step a) comprises 
contacting the liner with an elongate mass of cold-flowable material. In 
another preferred embodiment of the above method, step a) comprises 
contacting the liner with an elongate mass of material that is subject to 
cold flow at 20.degree. C. 
In another preferred embodiment of the above method, step c) comprises 
arranging first and second portions of a single, continuous wrapped 
elongate material. In an alternate embodiment, step c) comprises winding a 
first coil of wrapped elongate material about a central spool and 
subsequently winding a second coil of elongate material about the central 
spool such the core of the second coil is in contact with the tab of the 
first coil. In one aspect of this embodiment, the first and second coils 
are of a single, continuous elongate wrapped mass of material. 
In another embodiment, the above method includes the further step of 
bonding the first and second regions to one another. 
In another embodiment of the above method, step a) comprises extruding the 
mass of material onto the inside surface of the central region of the 
liner between the first and second regions. 
The above inventive method can also include the further steps of: d) 
removing the core of the second portion of wrapped mass of material from 
the tab of the first portion; d) separating the first and second regions 
of the liner to expose the mass of material; and f) removing the mass of 
material from the liner. The method can also include the further steps of 
g) contacting the central portion of the inside surface of the elongate 
liner with at least a portion of the outer peripheral surface of a second 
elongate mass of material; h) bringing the first and second regions of the 
inside surface of the liner together so as to enclose the second mass of 
material with the liner, thereby forming: (i) a core of wrapped material 
which includes the second mass of material and the center region of the 
liner and (ii) a tab of the wrapped material which includes the first and 
second regions of the liner; and i) arranging the second wrapped cold 
flowable material such that the core of a second portion of the second 
wrapped material applies sufficient force to the tab of a first portion of 
the second wrapped cold-flowable material so as to maintain the second 
mass of cold-flowable material enveloped by the liner at the first 
portion. 
The present invention also provides a method of enclosing a mass of 
cold-flowable hot melt adhesive with a liner, comprising the steps of: a) 
contacting a central portion of an inside surface of an elongate liner 
with at least a portion of the outer peripheral surface of an elongate 
mass cold-flowable hot melt adhesive, wherein the liner has first and 
second regions on opposite sides of the center region; b) bringing the 
first and second regions of the inside surface of the liner together so as 
to enclose the mass of cold-flowable hot melt adhesive with the liner, 
thereby forming: (i) a core of wrapped mass of cold-flowable hot melt 
adhesive which includes the mass of cold-flowable hot melt adhesive and 
the center region of the liner and (ii) a tab of the wrapped mass of 
cold-flowable hot melt adhesive which includes the first and second 
regions of the liner; and c) arranging the wrapped mass of cold-flowable 
hot melt adhesive such that the tab of a first portion of the wrapped mass 
cold-flowable hot melt adhesive and the core of a second portion of the 
wrapped mass of cold-flowable hot melt adhesive contact one another so as 
to maintain the mass of cold-flowable hot melt adhesive enveloped by the 
liner at the first portion. 
The present invention also provides a method of enclosing a mass of 
cold-flowable hot melt adhesive with a liner, comprising the steps of: a) 
contacting a center of an inside surface of an elongate liner with at 
least a portion of the outer peripheral surface of an elongate mass 
cold-flowable hot melt adhesive, wherein the liner has first and second 
regions on opposite side of the center region; b) bringing the first and 
second regions of the inside surface of the liner together in unbonded 
contact so as to enclose the mass of cold-flowable hot melt adhesive with 
the liner, thereby forming: (i) a core of wrapped mass of cold-flowable 
hot melt adhesive which includes the mass of cold-flowable hot melt 
adhesive and the center region of the liner and (ii) a tab of the wrapped 
mass of cold-flowable hot melt adhesive which includes the first and 
second regions of the liner in unbonded contact; and c) arranging the 
wrapped mass of cold-flowable hot melt adhesive such that the tab of a 
first portion of the wrapped mass cold-flowable hot melt adhesive and the 
core of a second portion of the wrapped mass of cold-flowable hot melt 
adhesive contact one another so as to maintain the mass of cold-flowable 
hot melt adhesive enveloped by the liner at the first portion. 
In yet another aspect, the present invention provides an apparatus for 
enclosing a mass of material with a liner. The apparatus comprises a) 
contacting means for contacting a central portion of an inside surface of 
an elongate liner with at least a portion of the outer peripheral surface 
of an elongate mass of material, wherein the liner has first and second 
regions on opposite side of the center region; b) folding means for 
folding the liner so as to contact the first and second regions of the 
inside surface of the liner so as to enclose the mass of material with the 
liner, thereby forming: (i) a core of wrapped mass of material which 
includes the mass of material and the center region of the liner and (ii) 
a tab of the wrapped mass of material which includes the first and second 
regions of the liner; and c) arranging means for arranging the wrapped 
cold flowable material such that the core of a second portion of the 
wrapped mass of material applies sufficient force to the tab of a first 
portion of the wrapped mass of material so as to maintain the mass of 
material enveloped by the liner at the first portion. 
Certain terms are used in the description and the claims that, while for 
the most part are well known, may require some explanation. It should be 
understood that, when referring to the first and second regions of the 
liner as being in "unbonded" contact, this means that the first and second 
regions are freely separable from one another and have not been bonded to 
one another such as by an adhesive, heat sealing, ultrasonic welding, or 
the like. It should also be understood that when referring to the material 
as "cold-flowable" this means that the material will exhibit 
time-dependent non-elastic deformation or strain under an applied load at 
temperatures below 120.degree. F. (50.degree. C.).

DETAILED DESCRIPTION OF THE INVENTION 
The present invention provides a wrapped mass of material. A preferred 
embodiment of the invention provides a cold-flowable material such as a 
hot-melt pressure sensitive adhesive wrapped in a liner such that the 
liner is easily removed from the material. The present invention also 
provides a method and apparatus for wrapping and unwrapping the material 
with the liner. 
The present invention is also useful for difficult to handle materials, 
such as materials which stick or bond to themselves. The present invention 
is also useful with materials which are not coherent or strong enough to 
be drawn through processing or delivery apparatuses themselves, and which 
are easily transported by drawing the liner which wraps the material. This 
can include materials in particulate form. 
FIG. 1 illustrates a mass of material 12 partially enclosed with a liner 20 
according to a first preferred embodiment of the present invention. FIG. 1 
shows the material in a partially wrapped state as taken along line I--I 
of FIG. 8. Referring to FIG. 1, the mass of material 12 has an outer 
surface 14. Liner 20 includes inside surface 26 which contacts the outer 
surface 14 of the material 12. Liner 20 also includes outside surface 28. 
Liner 20 has a first edge 22 and second edge 24 opposite to one another 
and extending for the length of the liner 20. Liner 20 is illustrated as 
having three regions: first region 30 extending along the length of the 
liner adjacent first edge 22; second region 32 extending along the length 
of the liner adjacent second edge 24; and center region 34 extending the 
length of the liner between the first region 30 and second region 32. The 
liner 20 contacts the outer surface 14 of the mass of material at the 
center portion 34 of the inside surface 26 of the liner. 
FIG. 2 illustrates the wrapped material 10 in a fully wrapped state. FIG. 2 
is taken along line II--II of FIG. 8. In the illustrated preferred 
embodiment shown in FIG. 2, the first region 30 and second region 32 of 
the liner are brought into contact at the inside surface 26 of the liner. 
Preferably, the first and second edges 22, 24 of the liner are 
substantially aligned with one another as illustrated, however this is not 
essential. The first and second regions 30, 32 of the liner together form 
a tab 36 of the wrapped material 10. The mass of material 12 and the 
center region 34 of the liner 20 together form a core 38 of the wrapped 
mass of material 10. In the preferred embodiment of the wrapped material 
10 illustrated in FIG. 2, the tab 36 of the wrapped material 12 extends 
away from the core 38. As illustrated in the preferred embodiment, the 
center portion 34 of the liner contacts most of the outer surface 14 of 
the material 12. The entire outer surface 14 of the material 12 can be, 
but is not required to be, in contact with the liner 20. It is also seen 
that in the preferred embodiment, the mass of material 12 is generally 
cylindrical, having a circular cross-section. This is a preferred 
configuration for the mass of material 12. It is understood, however, that 
other cross-sectional shapes of material 12 can be advantageously wrapped 
with liner 20 in accordance with the present invention. For example, the 
cross section of material 12 can be oval, oblong, tear-drop shaped, or 
polygonal with either rounded comers or more sharply defined corners. 
In a preferred embodiment of the present invention, the first and second 
regions 30, 32 of the liner 20 are in unbonded contact with one another 
along the inside surface 26 of the liner. When referring to the first and 
second regions of the liner as being in "unbonded" contact, this means 
that the first and second regions are freely separable from one another 
and have not been bonded to one another such as by an adhesive, heat 
sealing, ultrasonic welding, or the like. Keeping the liner 20 unbonded 
facilitates unwrapping the material as will explained in greater detail 
below. It is also within the scope of the present invention to bond the 
first and second regions 30, 32 of the liner to one another to enclose the 
mass of material 12 therein. Such bonding may be by means of an adhesive, 
heat sealing, ultrasonic welding, mechanical means, or the like, and can 
be chosen based on the material of the liner 20 and the desired strength 
of the bond. 
The wrapped mass of material 10 is preferably extremely long relative to 
the cross-sectional width of the material 12. This allows for convenient 
handling of large amounts of the material 12 by coiling the wrapped mass 
of material about a spool assembly 40 as illustrated in FIG. 3. For 
example, the length of the wrapped material 10 can be in excess of 100 
times the cross-sectional width of the material 12, and is preferably in 
excess of 1000 times the width of the material. It is understood that the 
present invention is not thereby limited, and that smaller and larger 
length to width ratios are within the scope of the present invention. As 
seen in FIG. 3, the wrapped material 10 is arranged in coils about the 
spool such that the core 38b of a second portion of the wrapped mass of 
material 10 applies sufficient force to the tab 36a of a first portion of 
the wrapped mass of material so as to maintain the mass of material 12 
enveloped by the liner 20 at the first portion. Successive coils of the 
wrapped material are likewise arranged so that the core of each successive 
coil contacts the tab of each respective preceding coil. That is, core 38e 
contacts tab 36d; core 38c contacts tab 36b, and so on. 
FIG. 4 is a view of the wrapped material of FIG. 3, in which the mass of 
material 12 is a cold-flowable material and has cold-flowed over time. The 
cross section of the core 38 of the wrapped material 10 in FIG. 4 has 
flowed to a generally rectangular cross section, conforming to the 
periphery of the central spool 42 of the spool assembly 40, and filling 
the voids that existed between the coils of the initially cylindrical 
material 12 that had been wound upon the spool assembly 40. 
The spool assembly 40 is illustrated in FIGS. 3 and 4 as having a single 
layer of wrapped material 10 wound about the central spool 42. It is 
understood that any desired numbers of layers of wrapped material 10 may 
be wound upon the spool, as determined by the cross sectional size of the 
core 38 of the wrapped material, the diameter of the central spool 42, and 
the diameter of the first and second end plates 48, 50, attached to the 
first and second ends 44, 46 respectively, of the central spool 42. Such 
multiple layers are illustrated in FIGS. 5-7. 
FIG. 5 illustrates the spool assembly 40 of FIG. 4, in which a second layer 
of wrapped material 10 has been wound about the first layer of wrapped 
material 10 already present central spool 42. As described above with 
respect to the first layer, the second layer is arranged such that tab 36b 
maintains pressure on the core 38c; tab 36a maintains pressure on core 
38b, and so on. This pressure between the tabs 36 and the cores 38 on the 
second layer of wrapped material 10 maintains the mass of material 
enveloped by the liner 20. 
FIG. 6 illustrates the spool assembly 40 and wrapped material 10 of FIG. 5, 
in which the cold-flowable material 12 of the second layer has cold flowed 
to conform to the first layer of wrapped material and to fill the voids 
that existed between the coils of the initially cylindrical material 12 
wrapped with liner 20 that had been wound upon the first layer of wrapped 
material 10. It is also seen that the second layer of wrapped material 
applies pressure to the first layer, further increasing the force applied 
to close the tabs 36 in the first layer. 
FIG. 7 illustrates the spool assembly 40 of FIG. 6, in which a third layer 
of wrapped material 10 has been wound about the second layer of wrapped 
material 10 already present on the central spool 42. The cores 38 in each 
coil of the third layer apply force to tabs 36 of each respective 
preceding coil in the third layer, as described above with respect to the 
first layer illustrated in FIGS. 3-4. In each of the just-described 
arrangements, the forces acting on the material 12 are at equilibrium, 
such that there are no unbalanced forces causing the material 12 to be 
forced out of the liner 20. 
The arrangement of wrapped material 10 illustrated in FIGS. 3-7 allows for 
the liner first and second regions 30, 32 to be unbonded, while 
maintaining the first and second regions 30, 32 under sufficient pressure 
to attenuate leakage of the material 12 from the liner 20. This is 
especially advantageous when the material 12 is a cold-flowable material. 
Thus, the present invention maintains the cold flowable material 12 in the 
liner 20, while allowing the liner to be easily and conveniently removed 
from the material 12 as discussed below. This provides the advantage of 
avoiding complex, time consuming, and expensive methods and apparatus for 
removing the liner from the material. It also allows for convenient re-use 
of the liner 20 because it is not damaged upon removal from the material 
12. It also allows selection of any desired liner material that provides 
the desired release characteristics for the particular material 12 to be 
wrapped, without concern for consuming the liner 20 when using a hot-melt 
pressure sensitive adhesive as the material 12, which previously required 
using a liner material compatible with the pressure sensitive adhesive. It 
is understood that relatively small amounts of the material 12 may leak 
from the liner 20, depending on the material rheology, liner 
configuration, spool configuration, and other factors, and that the liner 
will nonetheless be considered to maintain the mass of material enveloped 
by the liner. It is therefore preferred that the liner 20 have suitable 
release characteristics on both its inside surface 26 and outside surface 
28. 
Liners 20 useful in the present invention include woven and nonwoven 
fabrics, polymeric films, flexible papers, and the like which may be 
optionally coated or treated with a release material to modify at least 
the inside surface 26 of the liner, and optionally the outside surface 28 
of the liner. Examples of specific materials which are suitable for liner 
20 include silicone-coated fabrics, silicone-coated biaxially oriented 
polyester films, TEFLON films or fabrics, biaxially oriented polypropylene 
films, polyethylene films, and polyethylene coated fabrics or papers. The 
choice of the release coating, if any, on the liner 20 is generally 
selected to obtain desired release characteristics from the particular 
material 12. For example, a silicone release surface is preferable when 
material 12 is an acrylate pressure sensitive adhesive, while a TEFLON 
release surface may be preferable when material 12 is a silicone pressure 
sensitive adhesives. The liner material, and coating if present, is also 
chosen to get desired frictional engagement between the first and second 
regions of the liner 30, 32 when in contact to form tab 36, and to get 
desired friction between adjacent layers of the wrapped material. 
Material 12 can comprise any material which can be held in liner 20. The 
present invention is particularly well suited for use with pressure 
sensitive adhesives and heat activated adhesives. Pressure sensitive 
adhesives are adhesives which are tacky at room temperature and generally 
have a glass transition temperature below 0.degree. C. Heat activated 
adhesives are generally non-tacky or slightly tacky at room temperature, 
but become significantly tacky at elevated temperatures. The present 
invention is particularly well suited for use with adhesives, and other 
materials, which are cold-flowable materials, and particularly with 
materials which are cold-flowable at room temperature (20.degree. C.). 
Examples of adhesives which can be wrapped by the present invention include 
acrylate adhesives, such as those described in U.S. Pat. Nos. Re. 24,906 
(Ulrich); 4,833,179; 4,952,650; 5,292,844; 5,374,698; 5,464,916; and 
co-pending U.S. Pat. application Ser. No. 08/596,897 (Harmer et al); 
polyalpha-olefin adhesives; and ethylene vinyl acetate adhesives. 
The present invention is also useful for adhesives that may not exhibit 
cold flow, but are tacky or otherwise have a tendency to stick to 
themselves making handling difficult. Such adhesives include copolymer 
adhesives such as styrene-isoprene-styrene copolymers, styrene-butadiene 
copolymers, acrylonitrile rubber copolymers and the like. The copolymers 
are typically tackified and/or plasticized to make them pressure 
sensitive. The present invention is also useful with materials which are 
not coherent or strong enough to be drawn through processing or delivery 
apparatuses themselves, and which are easily transported by drawing the 
liner which wraps the material. This can include materials in particulate 
form. 
FIG. 8 is a partial schematic view of a wrapping apparatus 110 and method 
for wrapping a mass of material 12 with a liner 20 according to the 
present invention. A length of liner 20 is initially provided in roll form 
at liner spindle 112. The liner 20 progresses along tension sensing roller 
114 and idler rollers 116 and 118 and then around speed sensing roller 
120. Up until this point, the liner 20 is in a generally planer, unfolded 
state. After the liner 20 passes over speed sensing roller 120, the mass 
of material 12 is introduced onto the inside surface 26 of the liner at 
the center region 34 of the liner (as discussed above with respect to FIG. 
1, taken along line I--I of FIG. 8). Material 12 can be prepared at a time 
or location remote from the wrapping apparatus 110, and then delivered 
into the wrapping apparatus. Alternatively, the material 12 can be 
prepared (polymerized, blended, or compounded, for example, as appropriate 
for the particular material), and then introduced into wrapping apparatus 
110 in a continuous process. Furthermore, it is understood that extruding 
the material 12 through supply tube 122 and exit nozzle 124 is just one of 
many ways to introduce the material into the wrapping apparatus. The 
material 12 can be laid in place by any external conveyer. For example, 
material 12 can be extruded in a film or sheet form, and then repeatedly 
folded or wrapped upon itself to obtain a generally round cross section 
and then introduced into the wrapping apparatus. 
In the illustrated embodiment, the mass of material 12 is a cold-flowable 
material, such as a hot-melt pressure sensitive adhesive. The material 12 
is extruded in cylindrical form by supply tube 122 through exit nozzle 
124, as is commonly known to those of ordinary skill in the art of 
handling hot-melt materials. It is preferable to position the exit nozzle 
124 to introduce the material 12 at a height below the speed sensing 
roller 120 and the liner height adjusting assembly 130 (described below). 
This causes the liner 20 to begin to fold in half, with first and second 
edges 22, 24 of the liner substantially aligned with one another. An 
optional additional roller (not illustrated) can be positioned where the 
material 12 is deposited on the liner 20, with the optional roller at a 
height to force the material down below the edges 22, 24 of the liner 20 
to initiate and/or maintain the fold of the liner. Such an optional roller 
is preferably narrower than the liner 20. The partially enclosed material 
and liner then progresses through liner height adjusting assembly 130. 
As seen in FIGS. 9-11, liner height assembly 130 includes a first roller 
132 with a plurality of gripping rings 134 thereon. The gripping rings 134 
are arranged around the circumference of the first roller 132 generally 
perpendicular to the axis of rotation of the roller. Roller 132 is 
arranged such that the gripping rings 134 contact the second region 32 of 
the folded liner 20 on the liner outside surface 28. The materials of the 
rings is selected to engage the liner with sufficient friction to align 
the liner as described below. A similarly arranged roller (not 
illustrated) is provided on the opposite side of the folded liner 20 to 
contact the first region 30 of the folded liner on the liner outside 
surface 28. Center region 34 of the liner is seen at the bottom of the 
folded liner, and contains the material 12 therein. 
In one preferred embodiment, the first roller 132 includes rubber gripper 
rings 134 selected to provide desired frictional engagement with the 
particular liner 20. Alternative means for handling the liner can be 
substituted for the roller 132 having gripper rings 134 thereon. All that 
is required is that the height adjusting assembly 130 be able to engage 
the liner 20 and apply sufficient force to adjust the height of the edges 
22, 24 of the folded liner. For example, any roller type configuration 
having sufficient frictional contact with the liner can be used. This can 
include a roller 132 which itself has sufficient friction, or which has 
thereon any engaging means in place of gripper rings 134. 
FIG. 9 is an elevational view of the liner 20, material 12, and height 
adjusting assembly 130, in a direction looking from within the wrapped 
material 10, through the second region 32 of the liner 20 (shown in 
phantom for clarity) to the roller 132. Also seen schematically in FIG. 9 
is electric eye 140. When the electric eye determines that the second edge 
24 of the liner 20 is at the desired height then the roller 132 is 
oriented such that the gripper rings 134 are horizontal, so as to direct 
the liner forward (from right to left in FIG. 9) at a constant height. As 
seen in FIG. 10, the second edge 24 of the liner has dropped below the 
desired height. When electric eye 140 senses this, it sends a signal to an 
actuator (not illustrated) to orient the roller 132 such that the rings 
134 are at an angle relative to horizontal, thereby causing the second 
edge 24 of the liner to move upward as it passes the roller 132. When the 
liner is again at the desired height, as seen in FIG. 9, the electric eye 
140 senses this, and signals the actuator to orient the roller 132 such 
that the gripper rings 134 are again horizontal. The arrangement of the 
electric eye 140 is seen in FIG. 11. Electric eye 140 and reflector 142 
are oriented such that the liner 20 blocks the light emitted from the 
electric eye from reflecting off of reflector 142 back to a sensor in the 
eye. When the liner drops below the desired height, the light signal from 
the electric eye 140 reflects off of reflector 142 and returns to a sensor 
in the eye, indicating that the liner is too low. A similar arrangement 
can be provided for the roller engaging the first region 30 of the liner 
to maintain the first edge 22 at a desired height. 
The electric eye 140 and first roller 132 can operate in a binary mode as 
described above; that is, the eye determines whether or not the liner 
height is in a preferred range, and the roller 132 is actuated to a first 
or second position in response. Alternatively, an analog system can be 
used, in which the eye senses the position of the edge of the liner and 
the roller 132 is continuously adjustable within a range of motion 
depending on the height of the second edge 24 of the liner. 
After passing between the height adjusting assembly 130, the first and 
second regions 30, 32 of the liner 20 are in unbonded contact, with the 
material 12 contained in the center region 34 of the liner, as described 
above with respect to FIG. 2. Returning to FIG. 8, the wrapped material 10 
then progresses through belt assembly 150. The belt assembly includes an 
endless toothed belt 152 mounted on rollers 154. The belt 152 is arranged 
such that the teeth 156 engage with the outside surface 28 of the liner 20 
at the second region 32. The belt travels around idler rollers 154 so as 
to convey the wrapped material 10 to roller 160. A similar belt 
arrangement (not illustrated) is provided opposite to assembly 150, and is 
arranged so as to engage the outside surface 28 of the liner at the first 
region 30. The two belt assemblies are arranged to maintain the first and 
second regions 30, 32 of the liner in unbonded contact and to allow the 
core 38 of the wrapped material to pass underneath as the wrapped material 
10 is pulled toward the spool by rotation of the spool 40 and driven 
turntable 190 as described below. 
Other arrangements than the belt drive assembly are also within the scope 
of the present invention. What is required is some arrangement to maintain 
the first and second regions 30, 32 of the liner together as the wrapped 
material 10 is pulled toward the spool 40. For example, FIG. 8A is a top 
view of a conveying means which can be used in place of belt assembly 150. 
As seen in FIG. 8A, rollers 151 and 153 are arranged on opposite sides of 
the tab 36 of the wrapped material 10. Rollers 151 engage the outside 
surface 28 of the liner at second region 32, and rollers 153 engage the 
outside surface 28 at the first region 30. Rollers 151 and 153 are 
arranged such that their outer peripheries alternately extend beyond what 
would otherwise have been a straight line of travel for the wrapped 
material 10. The rollers are also arranged to engage the tab 36 of the 
wrapped material while allowing the core 38 to pass beneath the rollers 
151, 153. 
A cross section of roller 160 is illustrated in FIG. 8B. Roller 160 
includes an extended portion 164 for engaging the tab 36 of the wrapped 
material 10 as the wrapped material is pulled around roller 160 towards 
the spool 40. Roller 160 also includes a cavity 166 for engaging the core 
38 of the wrapped material. The cavity 166 is sized to have a smaller 
diameter than extended portion 164. 
The wrapped material 10 is then wound about spool assembly 40, as described 
above with respect to FIG. 3. As seen in FIG. 8, the spool 40 is provided 
on top of driven turntable 190. Turntable 190 rotates the spool 40 so as 
to coil the wrapped material about the central spool 42. To facilitate 
this, frame 162 is mounted on level wind tower 170. Mounted to frame 162 
are idler roller 118, speed sensing roller 120, liner height adjustment 
assembly 130, belt assembly 150 (or rollers 151, 153), and roller 160. 
Also mounted on the frame 162 is supply tube 122 with exit nozzle 124 for 
providing material 12 to the liner 20. Frame 162, with the components just 
described mounted thereon, is raised and lowered by level wind tower 170 
as the wrapped material 10 is coiled onto spool 40. 
The driven turntable 190 rotates the spool 40, thereby providing the 
driving force for pulling liner 20 through the wrapping apparatus 110. A 
variable brake is included in liner spindle 112 to maintain desired 
tension in the liner 20 as measured at tension sensing roller 114. Speed 
sensing roller 120 provides feedback to the turntable 190 to maintain the 
linear speed of the liner 20 constant, at a desired rate selected for the 
feed rate of material 12 to form the wrapped material 10. As additional 
layers of wrapped material 10 are added to the spool 40, the effective 
diameter increases. It is therefore necessary to decrease the rotational 
speed of the turntable 190 and spool 40 to maintain constant linear speed 
of the liner 20 at the speed sensing roller 120. The rate of travel of the 
frame 162 on the level wind tower 170 is controlled so as to be at a 
constant ratio relative to the rotational speed of turntable 190 and spool 
40. This provides the desired height advance (up or down as appropriate) 
of the wrapped material as it is being wound about the central spool 42. 
Accordingly, the rate of travel of the frame 162 on the level wind tower 
170 decreases proportionately to the decrease in rotational speed of the 
turntable 190 and spool 40. 
FIG. 12 is a partial schematic view of an unwind apparatus 210 and method 
for unwrapping liner 20 from the mass of material 12. The wrapped mass of 
material 10 is uncoiled from the spool 40 (not illustrated), and is 
initially in an enclosed state as illustrated in FIG. 3. Returning to FIG. 
12, the mass of material 12 is removed from the liner, and conveyed away 
on endless conveyor belt 230. The conveyor belt 230 is guided by rollers 
212, 214, 216, 218, 220, and 222, of which, 212 is a drive roller with the 
rest being idler rollers. The mass of material 12 can then be provided to 
any desired destination, such as the hopper of a hot-melt pressure 
sensitive adhesive applicator when the material 12 comprises a hot-melt 
pressure sensitive adhesive. 
The liner 20, after being separated from the material 12, is rewound onto 
liner take-up roll 298 for future use as follows. The liner first passes 
around idler 232 and then between upper separating assembly 240 and lower 
separating assembly 260. As described in more detail below, the spreader 
assemblies maintain the liner 20 in an unfolded state and centered in the 
unwind apparatus 210. The liner 20 then passes around idlers 280 and 282, 
and then around drive roller 290. Drive roller 290 maintains the linear 
speed of the liner 20 at a constant rate, selected as appropriate for the 
desired rate of feed of the unwrapped mass of material 12. As the layers 
of wrapped material 10 are unwound from the spool 40, the effective 
diameter decreases. Therefore, the rotational speed of the spool 40 must 
be increased to maintain constant linear speed of the liner at drive 
roller 290. Idler roller 282 is mounted on pivotable arm 284. The roller 
282 and arm 284 can have a desired weight or force applied to maintain the 
desired tension in the liner 20. A sensor on pivot arm 284 is used to 
determine when the motion of the arm exceeds an acceptable range in either 
direction. When the arm pivots too far upward, this is an indication that 
the spool 40 is not unwinding fast enough to keep up with drive roller 
290, and the unwind speed of the spool 40 is then increased. When the 
roller 282 and pivot arm 284 pivot downwards out of the desired range of 
motion, this indicates that the spool 40 is unwinding too quickly for the 
speed of the drive roller 290, and the speed of unwind of the spool 40 is 
accordingly decreased. Instead of the arrangement illustrated, it is also 
within the scope of the present invention to adjust the unwind speed of 
the spool 40 by other means. For example, the idler roller 284 can be 
mounted on a vertical slide means or dancer with a preselected allowable 
vertical range of motion to determine when the spool speed should be 
adjusted. 
After passing around drive roller 290, the liner 20 can optionally pass 
around tension sensing roller 292, idler rollers 294, 295, 296 and 297, 
and onto take-up roll 298. The tension sensing roller 292 provides 
feedback to a brake in liner take-up roll 298 to maintain the desired 
tension on the liner 20 as it is wound onto liner take-up roll 298. It is 
also possible to include an optional web edge guide just prior to the 
take-up roll as desired. 
The operation of the upper and lower spreader assemblies 240, 260 is shown 
in FIGS. 13-16. FIG. 13 is a top plan view of the liner 20 passing under 
the upper spreader assembly 240. Upper spreader assembly includes a first 
upper roller 242 having four gripping rings 244 mounted thereon. The first 
upper roller 242 is positioned such that the gripping rings 244 engage the 
inside surface 26 of the liner 20 at second region 32 adjacent second edge 
24. As seen in FIG. 13, the first upper roller 242 is in a first position, 
in which the gripping rings 244 are parallel to the direction of motion of 
the liner 20. The upper spreader assembly also includes second upper 
roller 246 having a plurality of gripping rings 248 mounted thereon. The 
second upper roller is positioned such that the gripping rings 248 engage 
the inside surface 26 of the liner at first region 30 adjacent first edge 
22. The gripping rings 248 are oriented to provide an outward force 
towards the first edge 22 as the liner traverses past the upper spreader 
assembly 240. 
FIG. 15 illustrates the lower spreader assembly, and its interaction with 
the upper spreader assembly 240. Lower spreader assembly 260 includes 
first lower roller 262 having four gripping rings 264 mounted thereon, and 
second lower roller 266 having four gripping rings 268 mounted thereon. 
Both the first and second lower rollers 262, 266 are mounted on pivoting 
arms (not illustrated) such that they may be brought into contact 
selectively with the outside surface 28 of the liner 20. When in its upper 
position, the first lower roller 262 is oriented such that its gripping 
rings 264 contact the outside surface 28 of the liner 20 at the second 
region 32 adjacent the second edge 24. The gripping rings 264 are oriented 
to provide an outward force towards the second edge 24 when engaged with 
the liner 20. When in its upper position, the second lower roller 266 is 
oriented such that its gripping rings 268 contact the liner outside 
surface 28 at the first region 30 adjacent the first edge 22. The gripping 
rings 268 are oriented to provide an outward force towards the first edge 
22 when engaged with the liner. 
In one preferred embodiment, rollers 242, 246, 262, 266 have rubber rings 
244, 248, 264, 268 thereon, selected to provide desired engagement with 
the particular liner 20. Alternative means for handling the liner can be 
substituted for the rollers having rubber rings thereon. All that is 
required is that the spreader assemblies be able to engage the liner and 
apply sufficient force to adjust the liner as described above. For 
example, any roller type configuration having sufficient frictional 
contact with the liner can be used. This can include a roller which itself 
has sufficient friction, or which has thereon any engaging means in place 
of the rings described herein. 
As illustrated in FIGS. 13 and 15, when the electric eye 250 senses that 
the second edge 24 of the liner is in an acceptable position, the first 
upper roller 242 is oriented such that gripping rings 244 are parallel to 
the direction of motion to the liner; the second upper roller 246 and 
second lower roller together apply an outward force in the direction of 
the liner first edge 22. The outward force applied by second upper roller 
246 and second lower roller 266 acts together with the force imparted by 
the first upper roller 242 to maintain the liner 20 under tension across 
its width, thus keeping the liner taut and unfolded. 
Electric eye 250 senses whether position of the second edge 24 of the liner 
is within an acceptable range. When the liner 20 has shifted too far in 
the direction of the 30 second upper roller 246, as seen in FIGS. 14 and 
16, the first upper roller 242 is shifted to a second position in which 
the gripping rings 244 apply an outward force in the direction of the 
second edge 24 of the liner. The first lower roller 262 contacts the 
outside surface 28 of the liner opposite the first upper roller 242. The 
rings 264 of the first lower roller also apply a force in the same 
direction as the first upper roller 242. The second lower roller 266 
shifts away from the outside surface 28 of the liner, and no longer 
applies force to the liner. In the arrangement shown in FIGS. 14 and 16, 
the liner 20 is urged in a direction toward the second edge 24 of the 
liner. When the electric eye 250 senses that the liner 20 has returned to 
its desired position, then the upper and lower spreader assemblies 240, 
260, return to the configuration illustrated in FIGS. 13 and 15. 
FIGS. 17-18 illustrate an alternate spreader assembly 270, in place of 
upper and lower spreader assemblies 240, 260. As seen in FIG. 17, spreader 
assembly 270 engages liner 20 after material 12 has been pulled away as 
described above, and before the liner passes over idler roller 280. As 
seen in FIG. 18, spreader assembly 270 includes first spreader arm 271 and 
second spreader arm 273. The spreader arms 271, 273 are pivotally mounted 
about the central axis of roller 280. This allows the arms 271, 273 to 
freely pivot up and down to maintain engagement between spreader assembly 
270 and the inside surface 26 of the liner 20. If desired, weight can be 
added to the arms 271, 273 to maintain a desired force of engagement. The 
location of mounting the arms 271, 273 is not critical to the operation of 
the invention. The arms 271, 273 could be mounted elsewhere, provided the 
spreader assembly 270 engages the liner 20 in approximately the same 
location as that illustrated. 
First spreader arm 271 has a first roller arm 272 pivotally mounted to the 
end of the arm 271 opposite to where arm 271 is mounted to the roller 280. 
Mounted on first roller arm 272 is a first roller 242, as described above 
with respect to the embodiment illustrated in FIGS. 13-16. First roller 
arm 272 is pivotally mounted to the spreader arm 271 allowing the first 
roller 242 to be oriented in a range of motion such that the gripper rings 
244 can direct the second edge 24 of the liner 20 to either side, or 
parallel to the direction of motion of the liner. Similarly, second 
spreader arm 273 has a second roller arm 274 pivotally mounted to the end 
of the arm 273 opposite to where arm 273 is mounted to the roller 280. 
Mounted on second roller arm 274 is a second roller 246, as described 
above with respect to the embodiment illustrated in FIGS. 13-16. Second 
roller arm 274 is pivotally mounted to the second spreader arm 273 
allowing the second roller 246 to be oriented in a range of motion such 
that the gripper rings 248 can direct the first edge 22 of liner 20 to 
either side, or parallel to the direction of motion of the liner. Electric 
eyes 250 determine whether each edge 22, 24 of the liner 20 is located 
within an allowable range of position. The electric eyes send a signal 
that causes either or both of the first and second rollers 242, 246 to 
pivot to cause the liner to shift in either direction as required, and to 
maintain the liner spread taut across its width. 
The present invention has now been described with reference to several 
embodiments thereof. The foregoing detailed description and examples have 
been given for clarity of understanding only. No unnecessary limitations 
are to be understood therefrom. It will be apparent to those skilled in 
the art that many changes can be made in the embodiments described without 
departing from the scope of the invention. For example, the liner can be 
chosen so as to be compatible with the hot melt adhesive, thus making it 
unnecessary to unwrap the hot melt adhesive before use. Also, it is 
possible to arrange discontinuous segments of wrapped material onto one 
another such that the core of one portion applies force to the tab of 
another portion, such as by laying portions of wrapped material next to 
one another in a container, or by wrapping individual portions in a 
cylindrical direction about a spool, rather than helically wrapping a 
continuous wrapped material about the spool. Furthermore, it is possible 
to have a second strip of material between the first and second regions of 
the liner when the liner is folded over the mass of material so as to make 
it easier to open the liner to unwrap the material. Thus, the scope of the 
present invention should not be limited to the exact details and 
structures described herein, but rather by the structures described by the 
language of the claims, and the equivalents of those structures.