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2008-07-22
10/455,541
2003-06-04
US 7,402,222 B2
2008-07-22
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Philip Tucker | Sing P. Chan
2023-08-09
A flocked transfer is produced by applying a release agent to a release sheet and then applying the flocking to the release agent. Unlike the traditional method, a binder and hot melt film is not applied to the back of the flock. The transfer (which is essentially a flocked release sheet) is then applied to a substrate (i.e., an item of clothing, a rubber pad, etc.) by positioning a sheet of thermosetting hot melt film on the substrate; placing the transfer on the hot melt film with the flock in contact with the hot melt film; and applying heat and pressure. The heat melts the thermosetting hot melt film to bind the flock to the substrate and binds the flocking together. This method reduces the costs involved in producing flocked articles, especially for articles produced on a continuous basis.
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B29C65/02 IPC
Joining of preformed parts ; Apparatus therefor by heating, with or without pressure
B32B37/16 IPC
Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding characterised by the properties of the layers with all layers existing as coherent layers before laminating
B32B38/00 IPC
Ancillary operations in connection with laminating processes
B44C1/165 IPC
Processes, not specifically provided for elsewhere, for producing decorative surface effects for applying transfer pictures or the like for decalcomanias; sheet material therefor
B44C1/17 IPC
Processes, not specifically provided for elsewhere, for producing decorative surface effects for applying transfer pictures or the like for decalcomanias; sheet material therefor Dry transfer
The present application is a divisional application of U.S. patent application Ser. No. 09/621,830, filed Jul. 24, 2000, of the same title to Abrams, which is incorporated in its entirety by this reference.
Not Applicable.
This invention relates to flocked transfers, and, in particular, to an improved method of making flocked transfers which can reduce the cost and time required of producing transfers by a significant amount.
Heretofore, flocked transfers have generally been produced by applying a release agent to a release sheet. The flocking is applied to the release sheet in the desired pattern. A binder and a permanent hot melt adhesive are applied to the back of the flocking, and the transfer is allowed to dry. The binder is required hold the flocking in the desired pattern. The hot melt adhesive, which is applied to the transfer as a powder, is used to adhere the transfer to a substrate, such as an article of clothing, a neoprene pad, etc. The transfer is applied to the substrate by placing the transfer on the substrate with the dried hot melt adhesive in contact with the substrate. Heat, such as from an iron, is then applied to the release sheet. The heat melts the hot melt adhesive to cause hot melt adhesive to flow into intimate contact with the substrate, forming a mechanical and molecular bond with the substrate. The release agent then allows for the release sheet to be removed from the transfer, leaving the flocking exposed on the substrate.
This traditional method has worked well for years. However, the method can be improved upon to reduce the cost of producing the transfer, and hence, the cost of the item containing the transfer.
In accordance with the invention, generally stated, a flocked transfer of the present invention is produced by applying a release agent to a release sheet and then applying the flocking to the release agent. Unlike the traditional method, a binder and adhesive are not applied to the ends of the flock.
To form an article of manufacture with the flocked transfer, a hot melt or thermosetting adhesive film (in the form of a sheet or cut to shape) is positioned on the substrate to which the transfer is to be applied. The thermosetting film is preferably a polyester or polyurethane film, but can be any thermosetting film. The flock with the release adhesive and release sheet (i.e., the transfer) is then placed on the sheet of permanent adhesive film with the release sheet up, so that the flocking is in contact with the permanent adhesive film. Heat is then applied to the transfer. The heat melts the permanent adhesive film, and secures the flock to the substrate. Because the permanent adhesive film is thermosetting in one embodiment, even if it is subsequently subjected to heat, it will not remelt, nor become tacky, and hence, there is no risk of fibers becoming matted down in any of this type of adhesive, which could otherwise ruin the plush pile effect. In addition, it is likely that the use of a thermoset powder could be added to a bond print latex flock adhesive binder, to serve as a method for increasing the adhesion and again reducing the risk of any remelting, or becoming tacky, when the flock transfer is subsequently exposed to heat. It is known that there is a much stronger adhesion with thermosetting materials, because thermoset materials will cross-link with a chemical reaction and thereby adhere the flock fibers to it, which become chemically attached thereto. Through the usage of this invention, the finished flock surface is more plush, soft, because more of the fiber is exposed and extends upwardly out of the adhesive, than with the screen-printed latex, as currently used. Also, this affords better soil release during washing or cleaning because of less fiber/adhesive entanglement occurs with the flock, during application.
FIG. 1 is a cross-sectional view of a prior art flock transfer;
FIG. 2 is a cross-sectional view of a flock transfer of the present invention;
FIG. 3 is an exploded view of the transfer, a permanent adhesive sheet, and a substrate used to make an article of manufacture;
FIG. 4 is a cross-sectional view of an article of manufacture using the transfer of the present invention, showing a part of the transfer applied to part of the substrate and a part of the transfer and permanent adhesive film spaced from the substrate; and
FIG. 5 is a schematic drawing of a process for continuously producing articles of manufacture, such as mouse pads, coasters, etc.
Corresponding reference numerals will be used throughout the several figures of the drawings.
The following detailed description illustrates the invention by way of example and not by way of limitation. This description will clearly enable one skilled in the art to make and use the invention, including what I presently believe is the best mode of carrying out the invention.
A prior art flocked transfer 101 is shown in FIG. 1. As is known, such transfers include a dimensionally stable release sheet 103 to which a conventional flock transfer release adhesive 105 is applied in a pattern which corresponds to the overall image to be flocked. The flock 107 is then electrostatically coated into the release adhesive 105. A binder adhesive 109 is applied to the exposed ends of the flock to bind the flock together as a unit. Lastly, a hot melt adhesive 111 is applied. The transfer is then allowed to dry. The transfer is applied to a substrate, as is known, by positioning the transfer on a substrate, such as a shirt or other item of clothing, with the hot melt adhesive in contact with the substrate, and applying heat to the transfer. The heat activates the hot melt adhesive to adhere the transfer to the substrate.
This process is described in my prior patent, U.S. Pat. No. 4,810,549, as well as in my co-pending U.S. application, Ser. No. 09/548,839 filed Apr. 13, 2000, both of which are incorporated herein by reference. In U.S. Pat. No. 4,810,549, a plush textured multicolored flock is disclosed in which differing colors of flock having a length greater than 0.3 mm are applied sequentially to a release adhesive coated base sheet through predetermined areas of masked screens. The applied flock is thereafter coated with a binder adhesive, such as a liquid water-based acrylic (40-60% water), which binds the flock into a unit. In one configuration, the binder adhesive contains an additional adhesive, such as a hot melt, for binding the transfer to a substrate. In an alternative configuration, the hot melt adhesive (which is usually a granular polyester or nylon) is formed as a separate layer. U.S. application Ser. No. 09/548,839, filed Apr. 13, 2000, discloses a mouse pad produced by applying differently colored flock (having a length of 1 mm and 3.3 Dtex) electrostatically through a screen to a release adhesive-coated paper sheet. A binder adhesive, such as a water-based acrylic, is screen printed to the flock after contacting the release adhesive. The binder adhesive may contain a hot melt or the hot melt may be applied to the free surface of the binder adhesive. The hot melt adhesive is bonded to a surface, such as a rubber pad, using heat and pressure. The release adhesive and paper sheet are then removed. In one process configuration, a flock-coated adhesive carrier sheet, a solid pre-formed binder adhesive film or heat seal film, and the rubber base material are thermally fused together in a drying oven.
A flocked transfer 1 of the present invention is shown in FIG. 2. The transfer 1 of the present invention includes a release sheet 3 to which a conventional release agent 5, such as wax, has been applied. The release agent is applied to the sheet in the shape of the pattern of the flocking. Flocking 7 is then applied to the release agent, and hence to the release sheet, to form the transfer. The flocking 7 is applied, for example, in the manner as described in my prior patent, U.S. Pat. No. 4,810,549, which is incorporated herein by reference. Unlike the prior art processes, the transfer 1 of this embodiment is made without the use of a binder adhesive or a hot melt adhesive. As is discussed below, a thermosetting film is used to adhere the transfer to a substrate.
An article of manufacture, such as an item of clothing having a transfer 1 applied thereto, a mouse pad, coaster, or other item having a flocked surface is easily produced using the transfer 1. The article of manufacture 11 is produced by positioning a hot melt or thermosetting permanent adhesive sheet 13 between a substrate 15 and the flocked release sheet. The sheet is, for example, a sheet of thermosetting polyester, available from Bostik, Inc. The sheet can also be made from a thermosetting polyurethane. Any other thermosetting film should also work well. The substrate can be an item of clothing, a rubber pad (for producing a mouse pad or coaster), etc. The sheet can be precut to correspond to the shape of the transfer 1. The transfer 1 is then positioned on the sheet with the flock 5 against the sheet 13. Heat is applied to the transfer through the release sheet to activate the permanent adhesive sheet. The sheet then acts to both bind the flock 5 together and to adhere the flock 5 to the substrate 15. Preferably, to assemble the article, the flocked release sheet, the permanent adhesive sheet (which is preferably the thermosetting film), and the substrate are brought together and passed through a heat-laminating press where the three parts are subject to temperature of about 300° F. (about 150° C.) and pressure (about 40-50 psi) for about 30 seconds. It has been found that a medium-to-firm pressure has been most advantageous in providing for assembly of this type of plush flocked transfer. The pressure and heat will cause the permanent adhesive sheet to adhere to the flock and the substrate. Additionally, the thermosetting film will cross-link or cure, to give a strong attachment of the flock to the substrate.
Articles, such as mouse pads or coaster, in which the entire top surface of the article is covered with the flocking can be produced on a continuous basis, as shown in FIG. 5. Rolls 21, 23, and 25 of a flocked release sheet 1, the permanent adhesive sheet 13, and the substrate 15 are provided. The three parts are brought together at a laminating station 33. Rollers can be provided in front of the station 33 so that the three elements are adjacent each other as they enter the laminating station. In the laminating station, heat and pressure are applied to the three sheets (the flocked release sheet, the permanent adhesive sheet, and the substrate) to melt the permanent adhesive sheet. The melted permanent adhesive sheet will then cure or cross-link, as noted above, to adhere the flock to the substrate. A web 35 exits the laminating station. The web 35 is then allowed to cool. The web 35 is ultimately directed to a cutting station where it is cut into individual articles. Once the web 35 is cooled, it can be directed immediately to a cutting station (after the sheet 35 cools), or can it can be wound up on an uptake roller to be cut into individual articles at a later time, or at a different location. At the cutting station, the release sheet is removed from the flock and gathered on an uptake roll or is otherwise disposed of. After the release sheet has been removed from the flock, the substrate with the flock adhered thereto is cut to form the articles 11. It is also likely that one could remove the release liner either before or after the die cutting procedure.
Preferably, the release sheet is flocked and supplied in roll form as shown in FIG. 5. However, the flocking of the release sheet could be made part of the process.
To produce flocked articles, such as shirts, jackets, etc., which cannot be easily flocked on a continuous basis, the permanent adhesive sheet can be applied to the transfer 1 prior to applying the transfer to the substrate. To do this, the thermosetting film is placed in contact with the flock of the transfer, and the transfer and release sheet are heated to a temperature at which the thermosetting film become tacky, but below the temperature at which the thermosetting film begins to cure and cross-link. This will adhere the thermosetting film to the transfer 1 to form a transfer which can later be applied to an article by positioned the transfer with the thermosetting film in position on the article (i.e., piece of clothing) and applying heat and pressure to the transfer, for example, with an iron, sufficient to melt the thermosetting film, to cause the film to cure and cross-link.
The method eliminates two steps from the-prior art method: (1) application of the binder adhesive and (2) application, cleaning, sintering, and drying of the hot melt adhesive. In a continuous process, the present method also eliminates a station for applying the binder and hot melt adhesives as well as a station for drying the completed transfer. Because a station is not needed to apply (i.e., print) the binder and hot melt adhesives to the flocking as part of the transfer, the machinery required to produce the article 11 is much less expensive (both in actual costs and in maintenance costs). Additionally, because the binder adhesive and hot melt adhesive is not used, the cost of the article of manufacture is significantly reduced.
As various changes could be made in the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.
1. A method of producing an article of manufacture having a flocked surface; the method comprising:
(a) supplying a flocked release sheet comprising a release sheet, a release adhesive adhered to the release sheet, and a plurality of flock fibers, with the flock fibers being adhered to the release sheet by the release adhesive;
(b) supplying a pre-formed, solid and self-supporting thermosetting adhesive sheet;
(c) thereafter contacting the flocked release sheet with the pre-formed, solid, and self-supporting thermosetting adhesive sheet, with the flock fibers being substantially perpendicular to an adjacent surface of the thermosetting sheet and the flock being positioned between the release sheet and release adhesive on the one hand and the thermosetting adhesive sheet on the other;
(d) while the flocked release sheet is in contact with the thermosetting adhesive sheet, heating and applying pressure to the pre-formed, solid, and self-supporting thermosetting adhesive sheet to tackify the thermosetting adhesive and embed ends of the flock fibers in the adhesive, thereby adhering the thermosetting adhesive to the flock of the flocked release sheet.
2. The method of claim 1 wherein the step of heating the thermosetting adhesive sheet comprises heating the thermosetting adhesive sheet to a temperature at which the thermosetting adhesive sheet becomes tacky, but below a temperature at which the thermosetting adhesive sheet begins to cure and cross-link and wherein the thermosetting adhesive sheet is later adhered to a substrate.
3. The method of claim 1 wherein the step of heating the thermosetting adhesive sheet comprises heating the thermosetting adhesive sheet to a temperature at which the thermosetting adhesive sheet cures and cross-links and wherein the thermosetting adhesive sheet is in contact with a substrate during heating and is adhered permanently to the substrate after heating.
4. The method of claim 3 wherein the thermosetting adhesive sheet is heated to about 300° F. and, while heated, subjected to a pressure from about 40 to about 50 psi.
5. The method of claim 1 wherein the thermosetting adhesive sheet is at least one of a thermosetting polyurethane adhesive film or a thermosetting polyester adhesive film having a substantially uniform thickness.
6. The method of claim 1, wherein at least most of the flock fibers are in direct contact with the thermosetting adhesive sheet.
7. The method of claim 1, wherein the interface between the flock and thermosetting adhesive sheet is at least substantially free of a binder adhesive.
8. The method of claim 7, wherein the thermosetting adhesive sheet is preformed before the adhering step (b).
9. The method of claim 1, wherein the release sheet and thermosetting adhesive sheet are on opposing surfaces of the flock.
10. The method of claim 1, wherein, after step (c), an embedded length of a flock fiber is positioned in the thermosetting adhesive sheet and wherein, for at least most of the flock fibers, the embedded flock length used for the thermosetting adhesive sheet is less than the embedded flock length used for a screen-printed latex.
11. The method of claim 1, wherein the flock is thermoplastically adhered to the thermosetting adhesive sheet before the thermosetting adhesive sheet is contacted with and adhered in a thermoset state to the substrate.
12. The method of claim 1, further comprising adhering the thermosetting adhesive sheet to a substrate to adhere the flock to the substrate.
13. The method of claim 12 wherein the step of heating the thermosetting adhesive sheet and the step of adhering the thermosetting adhesive sheet to the substrate are performed substantially simultaneously in a single operation.
14. The method of claim 12, wherein, after the heating step, an embedded length of a flock fiber is positioned in the thermosetting adhesive sheet and wherein, for most of the flock fibers, the embedded flock length used for the thermosetting adhesive sheet is less than the embedded flock length used for a screen-printed latex.
15. The method of claim 1, wherein the flock comprises a plurality of fibers substantially perpendicular to the release sheet, and wherein at least substantially all of the flock fibers that are substantially perpendicular to the release sheet contact the thermosetting adhesive sheet.
16. The method of claim 1, wherein, in step (c), the flock fibers are embedded in the thermosetting adhesive sheet to a desired and substantially uniform depth.
17. A method for continuously producing an article of manufacture having a flocked surface; the method comprising:
(a) providing a flocked release sheet comprising a release sheet, a release agent on the release sheet and a plurality of flock fibers attached to the release agent, wherein the flock fibers are formed in a desired pattern on the release sheet and are substantially perpendicular to the release sheet;
(b) providing a pre-formed, solid, and self-supporting thermosetting adhesive sheet;
(c) providing a substrate;
(d) thereafter contacting the thermosetting adhesive sheet, flocked release sheet, and substrate, with the thermosetting adhesive sheet being positioned between the release sheet and the substrate and the flock in contact with the thermosetting adhesive sheet, to produce a pre-assembly, wherein at least substantially all of the flock fibers that are substantially perpendicular to the release sheet contact the thermosetting adhesive sheet; and
(e) heating while applying pressure to the pre-assembly to soften and thermoset the thermosetting adhesive and thereby adhere the free surface of the flock and the substrate to the thermosetting adhesive sheet to form an article of manufacture, wherein the at least substantially all of the flock fibers are embedded in the thermosetting adhesive sheet.
18. The method of claim 17 wherein, the thermosetting adhesive sheet has a substantially uniform thickness.
19. The method of claim 17 wherein, the thermosetting adhesive sheet is a thermosetting polyester or a thermosetting polyurethane.
20. The method of claim 17, wherein the pressure applied to the pre-assembly ranges from about 40 to about 50 psi.
21. The method of claim 17, wherein at least most of the flock fibers are in direct contact with the thermosetting adhesive sheet.
22. The method of claim 17, wherein there is no binder adhesive in contact with the thermosetting adhesive sheet.
23. The method of claim 17, wherein the release sheet and thermosetting adhesive sheet are on opposing surfaces of the flock.
24. The method of claim 17, further comprising applying heat to the pre-assembly to adhere the flock fibers to the substrate; and removing the release sheet from the flock fibers to produce a flocked substrate.
25. A method of producing an article of manufacture having a flocked surface, comprising:
supplying a flocked surface comprising flock fibers;
supplying a pre-formed solid, and self-supporting thermosetting adhesive sheet having a substantially uniform thickness and substantially flat upper and lower surfaces;
thereafter contacting the thermosetting adhesive sheet with the flock fibers; and
while the flocked surface is in contact with the thermosetting adhesive sheet, heating and applying pressure to the flocked surface to soften the thermosetting adhesive and embed ends of the flock fibers in the thermosetting adhesive sheet, thereby binding the thermosetting adhesive sheet to the flock fibers;
wherein the step of heating the thermosetting adhesive sheet comprises heating the thermosetting adhesive sheet to a temperature at which the thermosetting adhesive sheet becomes tacky, but below the temperature at which the thermosetting adhesive sheet begins to cure and cross-link, and wherein the thermosetting adhesive sheet is later adhered to a substrate.
26. The method of claim 25 wherein the flocked surface comprises a release sheet and release agent in contact with a first side of the flocked surface, wherein the pressure applied to the flocked surface is from about 40 to about 50 psi, and wherein the thermosetting adhesive sheet is in contact with an opposing second side of the flocked surface.
27. The method of claim 25 wherein the thermosetting adhesive sheet is a thermosetting polyester and wherein there is no binder adhesive positioned between the flock fibers and thermosetting adhesive sheet.
28. The method of claim 25, wherein the thermosetting adhesive sheet is cut to a shape before the thereafter contacting step.
29. The method of claim 25, wherein the flock fibers are adhered to a first surface of the thermosetting adhesive sheet, wherein the thermosetting adhesive sheet has a second surface opposed to the first surface, and wherein there is no hot melt adhesive adjacent to the second surface.
30. A method of producing a flocked article, comprising:
(a) forming a flocked release sheet, the flocked release sheet comprising a release sheet, a release adhesive and flock adhered to the release sheet by the release adhesive;
(b) contacting a pre-formed, solid, and self-supporting thermosetting adhesive sheet to the exposed ends of the flock of the flocked release sheet, wherein the thermosetting adhesive sheet is formed before step (b); and
(c) while the thermosetting adhesive sheet is in contact with the flock, heating and applying pressure to the flocked release sheet and thermosetting adhesive sheet to soften the thermosetting adhesive and embed ends of the flock in the thermosetting adhesive, thermoplastically adhere the flock to the thermosetting adhesive sheet, and provide a transfer comprising the thermosetting adhesive sheet and the flocked release sheet, wherein embedded fibers of the flock are substantially perpendicular to an adjacent surface of the thermosetting adhesive sheet.
31. The method of claim 30, wherein step (c) is performed substantially in the absence of a binder adhesive positioned between the thermosetting adhesive sheet and the flock, and wherein the thermosetting adhesive sheet has a substantially uniform thickness before and after steps (b) and (c).
32. The method of claim 31, wherein the thermosetting adhesive sheet is free of an acrylic adhesive.
33. The method of claim 31, wherein the flocked substrate is free of a hot melt adhesive.
34. The method of claim 31, wherein the thermosetting adhesive sheet is cross-linked during the heating step (c) and wherein the pressure applied to the flocked release sheet and thermosetting adhesive sheet ranges from about 40 to about 50 psi.
35. The method of claim 31, wherein the thermosetting adhesive sheet is not substantially cross-linked before the heating step (c).
36. The method of claim 31, further comprising, after the heating step (c):
applying the thermosetting adhesive sheet to a substrate; and
heating the thermosetting adhesive sheet until the thermosetting adhesive is fully activated.
37. The method of claim 30, further comprising:
(d) thereafter contacting the thermosetting adhesive sheet with a substrate; and
(e) while the thermosetting adhesive sheet is contacted with the substrate, heating and applying pressure to the transfer to adhere the transfer to the substrate, wherein, in the adhering step (b), the interface between the thermosetting adhesive sheet and the substrate is at least substantially free of a binder adhesive and wherein the thermosetting adhesive sheet is in the thermoset state after step (e).
38. The method of claim 37, wherein, after step (c), an embedded length of a flock fiber is positioned in the thermosetting adhesive sheet and wherein, for at least most of the flock fibers, the flock length embedded in the thermosetting adhesive sheet is less than the flock length embedded in a screen-printed latex.
39. The method of claim 30, further comprising:
before step (b), precutting the thermosetting adhesive sheet to a desired final shape of the transfer.
40. The method of claim 30, wherein, in the heating step (c), the thermosetting adhesive sheet is heated to a temperature to soften the thermosetting adhesive.
41. The method of claim 30 wherein the step (b) of contacting the thermosetting adhesive sheet to the flocked release sheet and the step (c) of heating and applying pressure to the thermosetting adhesive sheet and the flocked release sheet are performed substantially simultaneously.
42. The method of claim 30, wherein a first surface of the thermosetting adhesive sheet in contact with the flock and a second opposing surface are each at least substantially free of a binder adhesive.
43. The method of claim 30, wherein the flock comprises a plurality of fibers substantially perpendicular to the release sheet, and wherein at least substantially all of the flock fibers that are substantially perpendicular to the release sheet contact the thermosetting adhesive sheet.
44. A method of producing a flocked transfer assembly, comprising:
providing a release agent on the release sheet;
flocking a plurality of flock fibers on the release agent in a desired pattern to define a free surface of the flock, wherein the release agent holds the flock to the release sheet, and wherein the flock fibers are substantially perpendicular to an adjacent surface of the release sheet;
providing a pre-formed, solid and self-supporting thermosetting adhesive sheet;
contacting the free surface of the flock with the thermosetting adhesive sheet such that at least most of a free surface of the flock is in direct physical contact with the thermosetting adhesive sheet; and
while the flock fibers are in contact with the thermosetting adhesive sheet, heating and applying pressure to the release sheet to force the ends of the flock fibers into the heated and softened thermosetting adhesive sheet, thereby adhering the thermosetting adhesive sheet to the free surface of the flock to produce a flocked transfer assembly, wherein the flock fibers are substantially perpendicular to an adjacent surface of the thermosetting adhesive sheet.
45. The method of claim 44, further comprising adhering the flocked transfer assembly to a substrate.
46. The method of claim 45, wherein the flock is thermoplastically adhered to the thermosetting adhesive sheet before the thermosetting adhesive sheet is contacted with and adhered in a thermoset state to the substrate.
47. The method of claim 44, wherein the thermosetting adhesive sheet is continuous and wherein, in the adhering step, pressure is applied to the release sheet while the thermosetting adhesive sheet is heated, the applied pressure ranging from about 40 to about 50 psi.
48. The method of claim 44, wherein there is no binder adhesive positioned between the flock fibers and thermosetting adhesive sheet.
49. The method of claim 44, wherein the thermosetting adhesive sheet is cut to a shape before the thereafter contacting step.
50. The method of claim 44, wherein the flock is adhered to a first surface of the thermosetting adhesive sheet, wherein the thermosetting adhesive sheet has a second surface opposed to the first surface, and wherein there is no hot melt adhesive adjacent to the second surface.