Patent Publication Number: US-6216422-B1

Title: Method and apparatus for wrapping material

Description:
This is a divisional of application Ser. No. 09/085,493, filed May 27, 1998. 
    
    
     TECHNICAL FIELD 
     The present invention relates generally to a wrapped mass of material and to methods and apparatus for wrapping such material. The present invention relates more particularly to a cold-flowable material, such as a hot-melt adhesive, wrapped in a liner. 
     BACKGROUND OF THE INVENTION 
     There have been several attempts to provide a means to package and handle materials such a hot melt adhesives or pressure sensitive adhesives. For example, U.S. Pat. No. 5,392,592, “Hot-Melt Pressure Sensitive Adhesive Packaging, Perform, 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 perform of the packaging material of Bozich et al. comprises a continuous sheet of a heat sealable film having two opposed edges, with a patterned silicon 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 a the tube is crimped to isolate desired amounts of adhesive between crimps. By melting the compatible 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 form 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 Veil 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. 
     Co-pending U.S. patent application Ser. No.: 08/753,461, filed on Nov. 25, 1996, now U.S. Pat. No. 5,848,696 discloses 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. 
     SUMMARY OF THE INVENTION 
     The present invention provides a wrapped mass of material and methods and apparatus for wrapping such material. A preferred embodiment of the invention provides a cold-flowable material such as a hot-melt adhesive or 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 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, powders, and liquids. 
     One aspect of the present invention presents a wrapped mass of material. The wrapped mass of material comprises a flexible liner and a mass of material including a peripheral surface. The liner includes an inside surface, an outside surface opposite the inside surface, a first edge, and a second edge opposite the first edge. The inside surface of the liner is at least partially wrapped around the peripheral surface of the mass of material forming a wrapped mass of material. The wrapped mass of material is spirally wound about itself. 
     In one preferred embodiment of the above wrapped mass of material, there are consecutive spirals of the wrapped mass of material in which a second spiral of the wrapped mass of material is supported by a first spiral of wrapped mass of material adjacent the second spiral. 
     In another preferred embodiment of the above wrapped mass of material, the wrapped mass of material includes consecutive spirals of the wrapped mass of material and a reinforcing film interposed between the consecutive spirals of the wrapped mass of material. 
     In another preferred embodiment of the above wrapped mass of material, the wrapped mass of material is in combination with a core, where the wrapped mass of material is spirally wound about the core. 
     In another preferred embodiment of the above wrapped mass of material, the liner is under tension so as to support the mass of material inside the liner. 
     In another preferred embodiment of the above wrapped mass of material, the mass of material includes an elongated cross-section. 
     In another preferred embodiment of the above wrapped mass of material, a portion of the peripheral surface of the mass of material remains exposed between the first edge and the second edge of the liner, forming an exposed surface of the mass of material. In another aspect of this embodiment, the first edge and the second edge of the liner extend beyond the exposed surface. 
     In another preferred embodiment of the above wrapped mass of material, the liner includes a first exposed surface extending along the first edge and a second exposed surface extending along the second edge, and a center surface extending between the first exposed surface and the second exposed surface, where the first exposed surface of the liner and the second exposed surface of the liner are unbonded. 
     In another preferred embodiment of the above wrapped mass of material, the liner includes a first exposed surface extending along the first edge and a second exposed surface extending along the second edge, and a center surface extending between the first exposed surface and the second exposed surface, wherein the first exposed surface of the liner and the second exposed surface of the liner are bonded together. 
     In another preferred embodiment of the above wrapped mass of material, the mass of material comprises a cold-flowable material. In another aspect of this embodiment, the cold-flowable material comprises an adhesive. In yet another aspect of this embodiment, the adhesive comprises a hot-melt adhesive. In another aspect of this embodiment, the adhesive comprises a pressure sensitive adhesive. In yet another aspect of this embodiment, the cold-flowable material is subject to cold flow at 20° C. In another aspect of this embodiment, the liner is meltable and mixable with the hot melt adhesive so as to provide a coatable hot melt adhesive composition. 
     In another preferred embodiment of the above wrapped mass of material, the liner comprises a cloth including a silicone release coating on at least the inside surface of the liner. 
     In another preferred embodiment of the above wrapped mass of material, the wrapped mass of material is in combination with a pallet including a first major surface and a second major surface opposite the first major surface, wherein the wrapped mass of material is supported by the first major surface. Another aspect of this embodiment further includes a core, where the wrapped mass of material is spirally wound about the core and where the core is engaged with the first major surface of the pallet. Yet another aspect of this embodiment further includes a spacer extending from the first major surface of the pallet and a second pallet supported by the spacer, the second pallet including a first major surface and a second major surface and a second wrapped mass of material supported by the first major surface of the second pallet. 
     In another preferred embodiment of the above wrapped mass of material, the mass of material is continuous. In another preferred embodiment of the above wrapped mass of material, the liner is continuous. 
     In another aspect, the present invention provides a wrapped mass of material, comprising a mass of cold-flowable adhesive including an elongated cross-section and a peripheral surface and a flexible liner. The liner has an inside surface, an outside surface opposite the inside surface, a first edge, and a second edge opposite the first edge. The liner is wrapped around the mass, and a portion of the peripheral surface of the material remains generally exposed. 
     In still another aspect, the present invention provides a mass of hot melt adhesive, comprising a flexible liner and a mass of hot melt adhesive. The liner includes an inside surface, an outside surface opposite the inside surface, a first edge, and a second edge opposite the first edge, a first exposed surface extending along the first edge, a second exposed surface extending along the second edge, a center surface extending between the first exposed surface and the second exposed surface. The mass of hot melt adhesive includes a peripheral surface, where the peripheral surface is in contact with the center surface of the liner forming a wrapped mass of hot melt adhesive, where the first exposed surface and the second exposed surface of the liner to extend away from the wrapped mass of hot melt adhesive, and where the first exposed surface and the second exposed surface of the liner are unbonded. The wrapped mass of hot melt adhesive is spirally wound about itself. 
     The present invention also provides a method for wrapped mass of cold-flowable material in a liner. The method includes the steps of: a) folding a liner, wherein the liner includes an inside surface, and outside surface opposite the inside surface, a first edge and a second edge opposite the first edge and wherein the fold is between the first edge and second edge, b) introducing a mass of cold-flowable material onto the liner, and c) spirally winding the wrapped mass of material about itself. In one preferred embodiment of this method, step b) proceeds step a). In another preferred embodiment of this method, step a) proceeds step b). 
     In yet another preferred embodiment of the above method, step b) comprises extruding the mass of cold-flowable material onto the liner. In another preferred embodiment of the above method, step b) comprises introducing a plurality of discontinuous masses of cold-flowable material onto the liner. 
     In another preferred embodiment of the above method, the mass of material is continuous. In another preferred embodiment of the above method, the liner is continuous. 
     In another preferred embodiment of the above method, the mass of cold-flowable material includes an elongated cross-section. In another aspect of this embodiment, the mass of cold-flowable material is subject to cold flow at 20° C. In yet another aspect of this embodiment, the mass of cold-flowable material comprises an adhesive. In another aspect of this embodiment the adhesive comprises a hot melt adhesive. Another aspect of this embodiment further includes steps of d) unwinding the wrapped mass of hot melt adhesive and e)melting the mass of hot melt adhesive and the liner, wherein the liner is meltable and mixable with the hot melt adhesive so as to provide a coatable hot melt adhesive composition. In another preferred embodiment of the above method, the adhesive comprises a pressure sensitive adhesive. 
     In another preferred embodiment, the above method further comprises the step of d) interposing a reinforcing film between consecutive spirals of the wrapped mass of material. In yet another preferred embodiment of the above method, step c) comprises spirally winding the wrapped mass of material about a core. 
     In another preferred embodiment, the above method further comprises the steps of d) spirally unwinding the wrapped mass of cold-flowable material and e) removing the mass of material from the liner. 
     In another preferred embodiment, the above method further includes the step of d) progressively traversing the spirally wound mass of material as additional spirals are provided. 
     The present invention also provides an apparatus for wrapping a mass of material in a liner, comprising a) a means for folding a liner, b) a means for introducing a mass of cold-flowable material onto the liner and c) a means for spirally winding the wrapped mass of material about itself. Another aspect of this embodiment further includes a means for progressively traversing the spirally wrapped mass as additional wraps are provided. 
     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 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° F. (50° C.) 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The present invention will be further explained with reference to the appended Figures, wherein like structure is referred to by like numerals throughout the several views, and wherein: 
     FIG. 1 is a cross-section of a wrapped mass of material partially wrapped with a liner according to a preferred embodiment of the present invention; 
     FIG. 2 is a cross-section of a wrapped mass of material with the liner bonded, enclosing the mass of material therein according to a preferred embodiment of the present invention; 
     FIG. 3 is a partial cross-section of the wrapped mass of material shown in FIG. 1 spirally wound about a core and supported by a pallet; 
     FIG. 4 is a view like FIG. 3, including additional spirals of the wrapped mass of material; 
     FIG. 5 is an isometric view of a preferred embodiment of a core for use with the present invention; 
     FIG. 6 is an isometric view a preferred embodiment of a first corner spacer; 
     FIG. 7 is an isometric view a preferred embodiment of a second corner spacer; 
     FIG. 8 is an isometric view of a preferred embodiment of a pallet for use with the present invention; 
     FIG. 9 is a side view of a preferred embodiment of the pallet of FIG. 8; 
     FIG. 10 is an isometric view of a preferred embodiment of the wrapped material, pallet, corner spacers and core; 
     FIG. 10A is an exploded view of the spirals of wrapped mass of material with an optional reinforcing film interposed between consecutive spirals; 
     FIG. 10B is an exploded view of an alternative embodiment of the spirals of wrapped mass of material; 
     FIG. 11 is a side view of a stack of multiple wrapped masses of material; 
     FIG. 12 is a partially schematic top view of an apparatus and method for wrapping a mass of material with a liner according to the present invention; 
     FIG. 13 is a side view of the apparatus of FIG. 12; 
     FIG. 14 is a view like FIG. 12 with a spiral wound mass of material; 
     FIG. 15 is a side view of a preferred embodiment of supply tube and exit nozzle; 
     FIG. 16 is a front view of the supply tube and exit nozzle of FIG. 15; 
     FIG. 17 is a side view of an unwrapped mass of material; 
     FIG. 18 is a cross-sectional view of one alternative wrapped mass of material; and 
     FIG. 19 is a cross-sectional view of a second alternative wrapped mass of material. 
    
    
     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 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 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, powders, and liquids. 
     FIG. 1 illustrates a mass of material  12  partially wrapped with a liner  18  according to a first preferred embodiment of the present invention. FIG. 1 shows the material in a wrapped state as taken along line  1 — 1  of FIG.  14 . The mass of material  12  has a peripheral surface  14 . Liner  18  includes inside surface  20  which contacts the peripheral surface  14  of the material  12 . Liner  18  also includes outside surface  22 . Liner  18  has a firsts edge  24  and second edge  26  opposite to one another and extending for the length of the liner  18 . Liner  18  is illustrated as having three regions: a first exposed region  28  extending along the length of the liner  18  adjacent first edge  24 ; a second exposed region  30  extending along the length of the liner  18  adjacent second edge  26 ; and a center region  32  extending the length of the liner  18  between the first exposed region  28  and second exposed region  30 . The liner  18  contacts the peripheral surface  14  of the mass of material  12  at the center region  32  of the inside surface  20  of the liner  18 . The exposed portion  16  of the peripheral surface  14  of the mass of material  12  which is not in contact with liner  18  extends between the first and second exposed regions  28 ,  30  of the liner  18 . The exposed surface  16  of material  12  is not in intimate and permanent contact with the inside surface  20  of the liner  18 . 
     Preferably, the first and second edges  24 ,  26  of the liner  18  are substantial aligned with one another as illustrated, however this is not essential. Preferably the first and second edges  24 ,  26  of liner  18  extend beyond the exposed surface  16  of the mass of material  12 , forming first and second exposed regions  28 ,  30 , as illustrated, however, this is not essential. Exposed surface  16  of the material may instead be flush with the first and second edges  24 ,  26  of the liner  18 . 
     In a preferred embodiment of the present invention, the first and second exposed regions  28 ,  30  of the liner  18  are unbonded to one another along the inside surface  20  of the liner  18 . When referring to the first and second exposed regions of the liner as being “unbonded,” this means that the first and second exposed regions may or may not contact one another, and, if in contact, 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  18  unbonded facilitates wrapping and unwrapping the material as explained in greater detail below. It is also within the scope of the present invention to bond the first and second regions  28 ,  30  of the liner to one another to enclose the mass of material  12  therein, as illustrated in FIG.  2 . The first exposed region  28  and second exposed region  30  of the liner  18  are bonded. 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  18  and the desired strength of the bond. It may be desirable to bond the first exposed region  28  and second exposed region  30  of liner  18  to prevent the material form being exposed to dirt, air, dust, or other contaminants. 
     All or much of the entire peripheral surface  14  of the material  12  is in contact with the liner  18 . In the preferred embodiment, the mass of material  12  has an elongated cross-section. However, any cross-sectional shapes of material  12  can be advantageously wrapped with liner  18  in accordance with the present invention. For example, the cross section of material  12  can be circular, oval, rectangle, oblong, tear-drop shaped, or polygonal with either rounded corners or more sharply defined corners. Typically, material  12  is flowable material and its ross sectional shape will conform to adjacent spirals and the supporting surface of pallet  34 . 
     The wrapped mass of material  10  is preferably extremely long in the spiral wrap direction relative to any cross-sectional dimension of the material  12 . This allows for convenient handling of large amounts of the material  12  by spirally winding a length of the wrapped mass of material about a core assembly  40 , as illustrated in FIG.  3 . For example, the length can be on the order of 50 or 100 times or more the longest cross-sectional dimension. Additionally, the height of the wrapped material  10  can be in excess of 200 times the cross-sectional width of the material  12 , and is preferably in excess of 6 times the width of the material  12 . Preferably, the mass of material has a height of 10 inches (25.4 cm) and a width of 1.5 inches (3.8 cm). It is understood that the present invention is not thereby limited, and that smaller and larger length ratios and height to width ratios are within the scope of the present invention. 
     FIG. 3 shows the spirally wound wrapped mass of material  10  taken along line  3 — 3  of FIG.  10 . The wrapped material  10  is arranged in spirals about the core assembly  40  and is supported by a pallet  34 . Pallet  34  includes a first major surface  36  and a second major surface  38  opposite the first major surface  36 . The first major surface of the pallet  34  supports the wrapped material  10 . Core assembly  40  engages with the first major surface  36  in the general center of pallet  34 . 
     The wrapped mass of material  10  is first wound around the core assembly  40 . Then the wrapped mass of material  10  is spirally wound about itself. As seen in FIG. 3, the wrapped material  10  is arranged in spirals about the core assembly  40  such that a first spiral  100  of the wrapped mass of material  10  is adjacent to a second spiral  110  of the wrapped mass of material. Such an arrangement allows the successive spirals to support one another, so as to maintain the mass of material  12  wrapped by the liner  18 . Successive spirals of the wrapped material are likewise arranged so that the outside liner surface  22  of each successive spiral contacts the outside liner surface  22  of each respective preceding spiral and so on. 
     FIG. 4 shows a finished spirally wound wrapped mass of material  10  taken along line  4 — 4  of FIG.  10 . Outside wrap  48  is wrapped in tension around the outer most spiral  120  of wrapped material  10  to support the wrapped material  10 . Outside wrap  48  may comprise tape, paper, film, cardboard, liner or any material with sufficient tensile strength, preferably at least of ten lbs./in. More preferably, outside wrap  48  comprises polyester or glass filament adhesive tape. The outside wrap  48  may only need to attach the end of the outermost spiral  120  to the previous spiral and may not need to be wrapped entirely around the outermost spiral  120 . The outer most spiral  120  is supported by the outside wrap  48  and the preceding spiral of wrapped material  10 . Each internal spiral of wrapped material  10  is supported on either side by the preceding spiral and the subsequent spiral of the wrapped material  10 . The pressure between the preceding spiral and the subsequent spiral of wrapped material  10  maintains the mass of material  12  wrapped by the liner  18 . In each of the just-described arrangements, the forces acting to the mass of that material  12  are at equilibrium, such that there are no unbalanced forces causing the mass of material  12  to be forced out of the liner  18 . The liner  18  can be considered to be acting as a trough to hold material  12 . 
     FIGS. 3 and 4 illustrate the wrapped material spirally wound about core assembly  40  supported by pallet  34 . Alternatively, the wrapped material  10  could be spirally wound about itself without a core assembly  40 . Furthermore, the wrapped material does not require a pallet  34  for support, but is convenient for storage and transportation of the material. 
     FIG. 5 illustrates a preferred embodiment of the core assembly  40 . Core assembly  40  is configured to engage with a pallet  34 . Core assembly  40  includes a core  47  having a peripheral surface  42  and a core center  44 . Core  47  includes a first end  43  and a second end  45  opposite the first end  43 . Core  47  includes two notches  41  in the first end  43 . The two notches  41  are located opposite each other. The core center  44  is located inside core  47 , extending across the interior of the core  47 . Core center  44  includes two core lets  46  extending from the second end  45  of the core  47 . Core legs  46  are configured to engage with first major surface  36  of pallet  34 , as shown in greater detail in FIG.  11 . Notches  41  are configured to receive the second major surface  38  of a second pallet  34  stacked on top of the first pallet  34 . 
     FIGS. 6 and 7 illustrate a preferred first corner spacer  50  and a preferred second corner spacer  60 , respectively. First spacer  50  and second spacer  60  are configured to engage with the first major surface  36  of a first pallet  34  and to support the second major surface  38  of a second pallet  34  stacked on top of the spacers  50 ,  60 . First spacer  50  and second spacer  60  are mounted in the pallet  34  in adjacent corners, as illustrated in FIG.  10 . Spacers  50  are mounted in pallet  34  diagonally opposite one another. Spacers  60  are also mounted in pallet  34  diagonally opposite one another. Several pallets  34  of wrapped material  10  may be stacked sequentially on top of one another using spacers  50 ,  60 , as illustrated in FIG.  11 . 
     First corner spacer  50  includes two walls  54 A,  54 B assembled 90° relative to each other. First corner spacer  50  includes a first end  51  and a second end  53  opposite the first end  51 . A notch  56  is located at the first end  51  of the spacer  50  where the two walls  54 A,  54 B meet. A corner leg  52  extends along both walls  54 A,  54 B at the 90° juncture and extends beyond the second end  53  opposite the notch  56 . First corner spacer  50  is configured to engage with pallet  34  by placing leg  52  into the corresponding cup  72  in the first major surface  36  of pallet  34 , as shown in greater detail in FIG.  11 . The notch  56  receives the bottom of a cut  72  extending from the second major surface  38  of a second pallet  34 . Walls  54 A,  54 B are configured to engage at their second end  53  with groove  39  located around the periphery of the first major surface  36  of pallet  34 . Walls  54 A,  54 B are configured to support at their first end  61  the second major surface  38  of a second pallet  34 . 
     Second corner spacer  60  includes two walls  64 A,  64 B assembled 90° relative to each other. Second corner spacer  60  includes a first end  61  and a second end  63  opposite the first end  61 . A notch  68 A is located in the general middle of the first wall  64 A in the first end  61  of spacer  60 . Another notch  68 B is located on the edge of the second wall  64 B in the first end of spacer  60  and is open to the edge of the second wall  64 B opposite form the 90° juncture. A support member  66  is located at the 90° juncture of the walls  64 A,  64 B. A leg  62  extends along the first wall  64 A and extends beyond the second end  63  of spacer  60  opposite the notch  68 A. Another leg  62  extends along the second wall  64 B and extends beyond the second end  63  of spacer  60  opposite the notch  68 B. Second corner spacer  60  is configured to engage with the pallet  34  by placing legs  62  into the corresponding cups  74 A,  74 B in the first major surface  36  of pallet  34 , as shown in greater detail in FIG.  11 . The notches  68 A,  68 B support the bottom of cups  74 A,  74 B extending from the second major surface  38  of a second pallet  34 . Walls  64 A,  64 B are configured to engage at their second ends  63  with groove  39  located around the periphery of the first major surface  36  of pallet  34 . Walls  64 A,  64 B are configured to support at their first end  61  the second major surface  38  of a second pallet  34 . 
     FIG.  8  and FIG. 9 illustrate a preferred embodiment of pallet  34 . FIG. 8 is an isometric view of pallet  34 . FIG. 9 is a side view of pallet  34 . Pallet  34  has a first major surface  36  and a second major surface  38  opposite first major surface. Around the periphery of the first major surface  36  is groove  39 . Core cups  70 A and  70 B are located near the middle of the first major surface  36  of pallet  34 . Core cups  70 A,  70 B are configured to engage with the legs  46  of core assembly  40 . Spacer cups  72  and spacer cups  74 A,  74 B are located in opposite corners of pallet  34 . Spacer cup  72  is configured to engage with the leg  52  of the first corner spacer  50 . Spacer cups  74 A,  74 B are configured to engage with legs  62  of the second corner spacer  60 . Cups  70 A,  70 B,  72 ,  74 A,  74 B also extend from the second major surface  38  of pallet  34 , as shown in FIG. 9, for engagement with the notches  41  in the first end  43  of the core  47 , notches  56  in the first end  51  of first spacer  50 , and notches  68 A,  68 B in the first end  61  of second spacer  60  of the stacked pallet  34  below. 
     FIG. 10 is an isometric view of a wrapped mass of material  10  supported by a pallet  34  with first corner spacer  50  and second corner spacers  60 . Walls  54 A,  54 B of first corner spacer  50  engage with groove  39  located around the periphery of the first major surface  36  of pallet  34 . Legs  52  of first corner spacers  50  engage with cups  72 . Legs  62  of second corner spacers  60  engage with cups  74 A,  74 B. Walls  64  of second corner spacer  60  also engage with groove  39  located around the periphery of the first major surface  36  of pallet  34 . 
     As illustrated in FIG. 10, the first edge  24  and second edge  26  of the liner  18  are unbonded. The material  12  inside the liner  18  of one spiral of wrapped material  10  is sufficiently supported on both sides of liner  18  by adjacent spirals of wrapped material  10  to attenuate the material  12  from being forced out of the liner  18 . 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  18 , 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  18  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  18  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. Alternatively, suitable liners may be used which are meltable and mixable with the hot melt adhesive so as to provide a coatable hot melt adhesive composition. 
     Liners  18  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  20  of the liner  18 , and optionally the outside surface  22  of the liner  18 . Examples of specific materials which are suitable for liner  18  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 release coating, if any, on the liner  18  is selected generally 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 adhesive. 
     It is understood that relatively small amounts of the material  12  may be forced out of the liner  18 , depending on the material rheology, liner configuration, spiral configuration, winding tension, temperature of material  12  and other factors, and that the material will nonetheless be considered a “wrapped mass of material” as that term is used herein, including the claims. It is therefore preferred that the liner  18  have suitable release characteristics on both its inside surface  20  and outside surface  22 , such as a silicon release coating. 
     FIG. 10A illustrates an alternative embodiment of wrapped mass of material  10 . As illustrated in FIG. 10A, an optional reinforcing film  80  may be interposed between sequential spirals, for example, between a first spiral  100  and a second spiral  110 . The reinforcing film  80  is wound with the wrapped material  10  as it is spirally wound about itself. The reinforcing film  80  provides additional support to the wrapped material  10 . 
     The wrapped mass of material  10  shown in FIGS. 1-4, and FIG. 10 is illustrated as including a continuous mass of material  12  and a continuous liner  18 . Alternatively, any number of discrete pieces of material  12  may be interspersed throughout liner  18 , as illustrated in FIG.  10 B. Furthermore, liner  18  may include any number of discrete lengths of liner  18 . Also, a first spiral  100  of wrapped mass of material  10  may be discontinuous from a second spiral  110  of wrapped mass of material  10 . 
     Any desired number of spirals of wrapped material  10  may be wound around the core assembly  40 , as determined by the cross sectional width of the wrapped mass of material  10 , the diameter of the core  47 , and the area of the first major surface  36  of pallet  34 . Preferably, the width of exposed surface  16  of material  12  is approximately 1.5 inches (3.8 cm). Preferably the height of the material  12  is 10 inches (25.4 cm). Preferably, 5 to 6 pounds (2.3-2.7 kg) of material  12  are wrapped by a 1 ft (30.5 cm) length of liner  18  in the spiral direction. Preferable dimension of pallet  34  are 3.75 ft by 4 ft (1.14 m by 1.22 m). A pallet of this size can hold 75-80 ft of liner  18  (22.8-24.3 m), containing approximately 450 lbs (205 kg) of adhesive. 
     FIG. 11 illustrates multiple pallets  34  of wrapped material  10  stacked vertically, one on top of the other. Core assembly  40 , first corner spacers  50  and second corner spacers  60  support he pallet  34  above them. The notches  41  located in the first end  43  of core  47 , the notches  56  in the first end  51  of first spacer  50 , and the notches  68 A,  68 B in the first end  61  of second spacer  60  are configured to receive the corresponding cups  70 A,  70 B,  72 ,  74 A,  74 B of pallet  34  located directly above core assembly  40  and spacers  50 ,  60 . Walls  54 A,  54 B of first corner spacer  50  at their second end  53  engage with groove  39  located around the periphery of the first major surface  36  of a first pallet  34  below and engage at their first end  51  with groove  39  located around the periphery of the second surface  38  of a second pallet  34  above, providing lateral support for both first and second pallets  34 . Walls  64  of second corner spacer  60  at their second end  63  engage with groove  39  located around the periphery of the first major surface  36  of a first pallet  34  below and support at their first end  61  the second surface  38  of a second pallet  34  above, providing lateral support for both first and second pallets  34 . 
     Material  12  can comprise any material which can be held in liner  18 . The present invention is particularly well suited for use with materials that are cold flowable at room temperature (about 20° C.), or materials that tend to stick to themselves at room temperature to form a large mass of material that may be difficult to handle. Such materials include A-B-A and A-B elastomeric block copolymers (such as styrene-butadiene copolymers, styrene-isoprene-styrene-block copolymers, and acylonitrile copolymers), pressure-sensitive adhesives (including those made from acrylates, ethylene-vinyl acetate, and tackified and/or plasticized block copolymers), thermosettable materials (such as epoxy resins), and the like. Block copolymers are commercially available form Shell Chemical Co. under the Kraton™ tradename. The present invention is also particularly well suited for use with pressure sensitive adhesives and hot melt adhesives. Pressure sensitive adhesives are adhesives which are tacky at room temperature ad generally have a glass transition temperature below 0° C. Hot melt 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° 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. 08/919,756 (Hamer et al) now U.S. Pat. No. 5,804,610; 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. The present invention is also useful with materials such as resins. 
     The present invention is also useful to package materials that are liquids at elevated temperatures and are solids at room temperature. This allows wrapping of material  12  while it is liquid and then cooling to a solid. 
     FIGS. 12-14 are a schematic views of a wrapping apparatus  200  and method for wrapping a mass of material  12  with a liner  18  according to the present invention. FIG. 12 is a top view of wrapping apparatus  200 . FIG. 13 is a side view of a wrapping apparatus  200  and liner  18 . FIG. 14 is a top view of the wrapping apparatus  200  with a wrapped mass of material  10  spirally wound about a core assembly  40 . 
     As illustrated in FIG. 13, a length of liner  18  is initially provided in a roll form at liner spindle  212 . Liner spindle  212  has a brake  213 . Brake  213  is set at a constant setting to inhibit spindle  212  from freely rotating, but instead to rotate with a slight amount of resistance. The liner  18  progresses from the liner spindle  212  to the nip assembly  214 . Nip assembly  214  includes roller  215 , roller  216 , encoder  226  and brake  228 . Roller  215  is preferably covered in rubber. Roller  216  has a first end  218  and a second end  220  opposite the first end  218 . Encoder  226  is attached to a first end  218  of roller  216 . Encoder  226  is any suitable device for measuring the rotational speed of roller  216  to determine the linear speed of the liner  18 . As illustrated, brake  228  is attached to the second end  220  of roller  216  and controls tension in liner  18 . It may be preferable to mount brake  228  and encoder  226  on separate rollers. Nip assembly  214  also prevents the liner  18  from slipping, which is desired so encoder  226  provides an accurate liner speed. 
     After the liner  18  passes through the nip assembly  214 , it passes over tension roller  240  and over feed roller  242 . Tension roller  240  has transducers  241  mounted on each end. The transducer  241  is any suitable device for measuring the tension on the liner  18  as it passes around the tension roller  240 . Up until this point, the liner  18  is in a generally planer, unfolded state. 
     After the liner  18  passes over feed roller  242 , the liner is introduced to the folding assembly  232 . Folding assembly folds liner  18  approximately in half before the mass of material  12  is introduced into the fold. Folding assembly  232  includes two V-bars  236  and a cross bar  238 , forming a triangle. Cross bar  238  is parallel with the axis of feed roller  242  and provides support to both V-bars  236 . V-bars  236  are tilted downward in the direction from feed roller  242  and are attached for support to a supply pipe  222 . The liner  18  first passes under cross bar  238 . The first edge  24  and second edge  26  of liner  18  remain relatively aligned as the V bars  236  introduce a fold into the liner  18 . V bars  236  include air holes  234  running the length of the V bars  236 . The air holes  234  blow air against the liner as the liner  18  passes against the bars  236  thereby reducing friction between the liner  18  and the V bars  236  as the liner  18  is pulled into guide roll assembly  250 . 
     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  flows from an extruder  204  into supply tube  222  and through exit nozzle  224 , as is commonly known to those of ordinary skill in the art of handling hot-melt or cold flowable materials. The mass of material  12  is introduced onto the inside surface  26  of the liner at the center region  34  of the liner by nozzle  224 . Nozzle  224  may be one continuous nozzle or a series of nozzles. A preferred embodiment of nozzle  224  is illustrated in FIGS. 15-16. It is preferable to position the exit nozzle  224  to introduce the material  12  at a height below the first and second edges  24 ,  26  of the liner  18 . Material  12  can be prepared (polymerized, blended, or compounded, for example, as appropriate for the particular material) at a time or location remote from the wrapping apparatus  200 , and then delivered into the wrapping apparatus  200 . Alternatively, the materials  12  can be prepared and then introduced into wrapping apparatus  200  in a continuous process. Furthermore, it is understood that extruding the material  12  through supply tube  222  and exit nozzle  224  is just one of many ways to introduce the material into the liner  18 . The material  122  can be introduced onto the liner  18  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 elongated cross section and then introduced into the liner  18 . 
     As material  12  is introduced into liner  18 , the liner is pulled through the guide roll assembly  250 . Guide roll assembly provides a place to load the material  12  into the liner fold and guides the wrapped mass of material  10  to the pallet  34 . Guide roll assembly includes a first row  254  of eight vertical rollers  252  and a second row  256  of eight vertical rollers  252 . The first row  254  of rollers  252  is hinged on the roller  252 C and can pivot away from the second row  256  of rollers  252 . This allows an operator to access the exit nozzle  224 , easily thread liner  18 , inspect nozzle flow or make nozzle adjustments. The second row  256  of rollers  252  is stationary. All eight of the rollers  252  in the first row  254  are non-driven. Drive roller  252 A and drive roller  252 B of the second row  256  are driven. The liner  18  near first edge  24  is pulled by drive roller  252 A and drive roller  252 B. The section of liner near the first edge  24  will have a tendency to slack because that side of the liner  18  will be at a smaller radius than the opposite side of the wrapped material  10  as it is spirally wound around core assembly  40 . Drive rollers  252 A and  252 B ensure that the liner  18  near first edge  24  will not slack as the wrapped material  10  is spirally wound around core assembly  40  forming spirals of wrapped material  10  adjacent to one another. Preferably, drive rollers  252 A,  252 B are wrapped with silicone belt material. This provides sufficient friction between the rollers  252 A,  252 B and the liner  18  as it goes through the guide roll assembly  250 . The rotational speed of the drive rollers  252 A,  252 B is above the linear speed of the liner  18 . Preferably, the rotational speed of drive rollers  252 A,  252 B is 150% of the linear speed of the liner  18 . 
     The wrapped mass of material  10  exists the guide roller assembly and is spirally wound around core assembly  40  mounted in the middle of the first major surface  36  of pallet  34 , as described above with respect to FIG.  3 . To start spirally winding the wrapped material  10  around core assembly  40 , the wrapped material is taped manually to the core assembly  40 . As seen in FIGS. 13-14, the pallet  34  is provided on top of driven turntable  150 . Turntable  150  rotates the pallet  34  so as to spirally wind the wrapped material  10  about the core assembly  40 . Turntable motor  244  rotates the drive sprocket  246  which drives a chain  248  which rotates the turntable sprocket  243  thereby rotating turntable  150 . The driven turntable  150  rotates the pallet  34 , thereby providing the driving force for pulling the wrapped material  10  through the guide roll assembly  250 . The pallet  34  is clamped to turntable  150  during operation and the core assembly  40  is externally clamped to pallet  34  during operation. 
     A computer or programmable logic controller, referred to herein as a “PLC,” uses information received from encoders or other sensors in the apparatus  200  to control various parameters such as speed or operation of motors used to rotate turntable  150  and to more turntable  150  laterally, and to control the tension and speed of the liner  18 . 
     As illustrated in FIG. 14, it is preferred that the wrapped material  10  about to be wound around core assembly  40  be oriented generally tangentially to the already spirally wound material  10  around core assembly  40  so as to reduce or eliminate slack on wrapped material  10 . To maintain the wrapped mass  10  exiting the guide roll assembly  250  generally tangent to the wrapped material  10  previously wound around core assembly  40 , turntable  150  traverses laterally as the diameter of the already spirally wound wrapped material  10  increases as shown by arrow A. To facilitate this, turntable  150  is mounted on a movable frame which is laterally moved by ball screw  160 . (See FIG. 12.) An indexing motor  260  drives the ball screw  160  thereby causing turntable  150  to traverse laterally from position A to position B (shown in phantom lines for clarity), as illustrated in FIG.  12 . Wheels  266  mounted on the movable frame roll on track  262  to maintain the direction of turntable  150 . Track  262  is orientated at an angle β relative to a line perpendicular to the guide roll assembly  250 . Preferably, angle β is between 11-15°. More preferably, angle β is 12°. 
     As shown schematically in FIGS. 12 and 14, a sensing arm  270  is attached to the guide roller assembly  250  and located between the guide roller assembly  250  and core assembly  40  mounted in the pallet  34 . Sensing arm  270  provides feedback to the PLC or computer which in turn controls the operation of the turntable index motor  260 . As the diameter of the already wound material  10  on core assembly  40  increases, the material  10  contacts and moves the sensing arm  270  sending a signal to the PLC to start the indexing motor  260  mounted below turntable  150  to drive the turntable  150  away from the sensing arm  270 , towards position B. As the turntable  150  moves away from the sensing arm, the wound material  10  comes out of contact with the sensing arm  270  which sends a signal to the PLC to deactivate the index motor  260 . This process repeats again when the diameter of the wrapped material  10  on core assembly  40  increases enough to contact the sensing arm  270 . This process continues until the turntable  150  and the moveable frame move from position A to position B, as illustrated in FIG.  12 . As the index motor  260  turns the ball screw  160 , the number of rotations of the ball screw  160  is counted. The number of ball screw rotations are used to calculate the distance the turntable has been traversed, which is used to calculate the diameter of the already wound material  10 . At position B, no more wrapped material  10  will be wound around core assembly  40 . 
     A first encoder  268  is mounted on the turntable motor  244  to measure the rotational speed of the turntable  150 . It is preferred to keep the liner speed constant during the operation of the apparatus  200 . The rotational speed of the turntable  150  therefore will need to decrease as the diameter of the wrapped material  10  around core assembly  40  increases, as described above. 
     A second encoder  226 , mounted on the first end  218  of roller  216 , measures the linear speed of liner  18 . The computed liner speed, based on the diameter of the already wrapped material  10  mentioned above and rotational speed of the turntable  150 , is compared by the PLC to the actual linear speed of the liner  18 , which is measured by the second encoder  226  mounted on roller  216 . If the actual speed of the liner  18  measured at roller  216  is at least 20% greater than the calculated liner speed at the turntable  150 , then the PLC signals the turntable  150  speed to increase. This reduces or eliminates slack in the wrapped material  10  as it is spirally wound about core assembly  40 . This greater than 20% differential could occur if material  12  exiting nozzle  224  into guide roller assembly  250  is thick enough to increase the force between the drive guide rollers  252 A,  252 B and the liner  18  causing the liner  18  to increase its line speed up to the drive guide roller speed of 150% of line speed. When this occurs, the PLC signals the turntable  150  to increase it&#39;s rotational speed to accommodate the increased speed of the wrapped material  10  exiting the guide roll assembly  250 . With this increased liner speed, the thickness of the material  12  will decrease, thus decreasing the force between the drive rollers  252 A,  252 B and liner  18 . 
     As seen in FIGS. 12-14, a transducer  241  is mounted on the tension roller  240  for measuring the tension in the liner  18 . A brake  228  is mounted on the second end  220  of roller  216 . As the liner tension measured by transducer  241  increases or decreases, the PLC will tighten or loosen brake  228  on roll  216  appropriately to maintain a generally constant liner tension Preferably, liner tension is set at 10 lbs (44N). Desired liner tension depends on liner strength, desired wrapping tension, and matieral rheology. 
     Also seen schematically in FIGS. 12-14, an electric eye  280  is mounted next to the folding assembly  232 . When the electric eye senses that liner  18  is not running along the folding assembly  232  or is not at the desired height, it sends a signal the PLC which in turn sends a signal to the extruder  204  and the turntable drive motor  244  to stop. This prevents matieral  12  from being introduced by the exit nozzle  224  into the guide roller assembly  250  without a liner  18  present or with the liner  18  out of position. 
     The method for wrapping a mass of material  12  with a liner illustrated in FIGS. 12-14 and described above includes the steps of: a) folding a liner  18 ; b) introducing a mass of material  12  onto the liner  18 ; and c) spirally winding the wrapped mass of material  10  about itself. It is understood that the order of step a) and step b) may be interchanged, such that the mass of material  12  may be first introduced onto liner  18  and then the liner  18  may be folded prior to spirally winding the wrapped mass of material. 
     The method for unwrapping the mass of material  12  includes the steps of a) unwinding the wrapped mass of material  12  and b) removing the liner  18  from the mass of matieral  12 . Alternatively, if the material  12  is a hot melt adhesive and the liner  18  is meltable and mixable with the hot melt adhesive so as to provide a coatable hot melt adhesive composition, the wrapped adhesive maybe melted with the liner  18 . 
     An alternative method for unwrapping a wrapped mass is described in co-pending U.S. application Ser. No.: 08/753461, filed on Nov. 25, 1996, now U.S. Pat. No. 5,848,696, the entire disclosure of which is incorporated herein by reference. 
     FIGS. 15 and 16 illustrate a preferred embodiment of a supply tube  222  and exit nozzle  224 . FIG. 15 is a side view of supply tube  222  and exit nozzle  224 . FIG. 16 is a front view of supply tube  222  and exit nozzle  224 . Supply tube  222  and exit  224  are configured to deliver a uniform volume flow of material  12  into liner  18  throughout the cross-section of material  12 . An elongated slot is located in supply tube  222  and extends upward from first end  291 . Exit nozzle  224  is attached to supply tube  222  at the slot. Exit nozzle  224  includes two side plates  292 , top plate  290 , and bottom plate  299 . The material  12  flows through the opening provided within side plates  292  and top plate  290  and bottom plate  299 . Top and bottom plates  290 ,  299  are generally parallel to each other and are tilted downward at angle α. Angle α is preferably 110°-125°, and more preferable 116°. Side plates  292  are generally parallel to one another and are connected by a series of bolts  294 , which extend entirely across the opening between the plates  292 . The exit nozzle  224  is designed to deliver material  12  from the bottom of fold in the liner  18  to within one to two inches from edges  24  and  26 . Plates  292  also include threaded flow control bolts  296  which may be adjusted to varying lengths. The number, position, and lengths of threaded flow control bolts  296  are adjusted to provide a uniform pressure drop of material  12  from supply tube  222  through the exit nozzle  224  into liner  18  thereby delivering a uniform volume flow of material  12  into liner  18 . 
     As previously mentioned, the method of wrapping a material  12  with a liner  18  may be described by the steps of: a) introducing a mass of material  12  onto the liner  18 ; b) folding liner  18 ; and c) spirally winding the wrapped mass of material  10  about itself. FIG. 17 illustrates an alternative embodiment of step a). FIG. 17 is a side view of an unwrapped mass of material. Positions X, Y, and Z are illustrated on liner  18  to indicate where folds are to be made in the material  12  and liner  18 , as described in greater detail below. Material  12  is a layer introduced onto liner  18 , extending between a first exposed region  28  and a second exposed region  30  of liner  18 . Material  12  may be cured or polymerized by exposure to ultra violet light, for example, before folding liner  18 . 
     FIGS. 18 and 19 illustrate alternative wrapped masses of the material of FIG.  17 . FIG. 18 is a cross-sectional view of one alternative wrapped mass of material and FIG. 19 is a cross-sectional view of a second alternative wrapped mass of material  10 . 
     The wrapped mass of material  10  illustrated in FIG. 18 is first formed as material  12  and liner  18 , as illustrated in FIG.  17 . Next, material  12  and liner  18  are folded lengthwise at position Y and position Z so that material  12  is folded onto itself. Then, material  12  and liner  18  are folded at position X so that liner  18  is folded back on itself to form the cross section illustrated in FIG.  18 . Lastly, the wrapped material  10  is spirally wound about itself. 
     The wrapped mass of material  10  illustrated in FIG. 19 is first formed as material  12  and liner  18 , as illustrated in FIG.  17 . Next, material  12  and liner  18  are folded in half lengthwise at position X so that material  12  inside liner  18  is folded onto itself. Then, material  12  and liner  18  are folded to bring position X to the W position. Then, material  12  and liner  18  are folded at position W to form the cross section illustrated in FIG.  19 . Lastly, the wrapped material  10  is spirally wound about itself. 
     The present invention has not 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. 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.