Abstract:
Articles of apparel and the method of making the same which include a uniquely constructed fleece liner and an elastomeric polyurethane film that will allow water vapor due to perspiration to transpire through the article, but will prevent water from external sources from reaching the wearer&#39;s extremities. The fleece liner component is constructed using a novel adhesive bonding process that produces a virtually seamless liner component that provides substantial warmth and comfort to the user.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    The present invention relates generally to articles of apparel. More particularly, the invention concerns improved articles of apparel used to cover the wearer&#39;s extremities such as an improved, waterproof sock that includes a novel, stretchable fleece liner that adds comfort and warmth to the sock and an elastomeric polyurethane film that permits perspiration to transpire through the sock, but keeps water from external sources away from the wearer&#39;s foot.  
           [0003]    2. Discussion of the Prior Art  
           [0004]    Various attempts have been made in the past to produce breathable, water-proof articles of apparel such as gloves and socks that will keep the wearer&#39;s hands and feet dry and at the same time permit perspiration to transpire through the article. Materials, which will accomplish this desired function, have been known for sometime. Among the most successful waterproof, breathable articles of apparel ever developed are those developed by the present inventor and described in U.S. Pat. Nos. 5,402,540, 5,655,226 and 5,483,703. Because of the pertinence of these patents to a complete understanding of the present inventions, U.S. Pat. Nos. 5,402,540, 5,655,226 and 5,483,703 are incorporated by reference as though fully set forth herein.  
           [0005]    The present invention constitutes an improvement in the articles described in the aforementioned patents. More particularly, the articles of apparel of the present invention include a novel fleece liner component that is constructed in a highly novel manner to provide substantial warmth and comfort to the user.  
           [0006]    As will be better appreciated from the discussion which follows, the present invention provides, for the first time, articles of clothing such as socks and gloves which exhibit the warmth, comfort and stretchability of traditional types of sport socks and gloves. The articles of the invention include a uniquely constructed fleece liner component and a barrier membrane component that provides an article that is both breathable and completely waterproof.  
           [0007]    While certain articles of clothing have been fabricated in the past using fleece materials, the articles have been constructed using traditional cutting and sewing techniques. These techniques produce articles that exhibit welts that are generally unacceptable in articles of clothing such as socks and gloves. The fleece articles produced in the traditional manner have proven unacceptable for use in the construction of the three-ply waterproof and breathable articles of clothing of the present invention. Accordingly it was necessary for the present inventor to conceive of and develop an entirely new and novel method for the construction of the fleece articles that do not exhibit the undesirable welt characteristics found in the prior art sewn garments.  
         SUMMARY OF THE INVENTION  
         [0008]    It is an object of the present invention to provide comfortable articles of apparel and the method of making the same which include a uniquely constructed fleece liner and an elastomeric polyurethane film that will allow water vapor due to perspiration to transpire through the article, but will prevent water from external sources from reaching the wearer&#39;s extremities.  
           [0009]    A particular object of the invention is to provide a footwear article of the aforementioned character which includes a fleece liner component that provides substantial warmth and comfort to the user.  
           [0010]    Another object of the invention is to provide an article as described in the preceding paragraphs in which the fleece liner component is constructed using a novel adhesive bonding process that produces a virtually seamless liner component.  
           [0011]    Another object of the invention is to provide a method of making articles of the character described in the preceding paragraphs which is simple and straight forward, does not require the use of complicated equipment and can be performed by unskilled workmen with a minimum of training.  
           [0012]    A particular object of the invention is to provide a sock as described in the preceding paragraphs which is of simple construction, is lightweight, is pliant and durable in use, and is easy to manufacture.  
           [0013]    In one form of the invention, the footwear article comprises a sock having a body portion that is of three-ply construction with the inside ply being formed from a uniquely constructed fleece liner that embodies elastic fibers, the intermediate ply being made from an elastomeric polyurethane film and the outside ply being formed from a suitable stretchable fabric. The three plies are uniquely bonded together using a pliant, waterproof adhesive to provide a rugged, durable and extremely comfortable sock. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0014]    [0014]FIG. 1 is a generally perspective, diagrammatic view illustrating the first step in one form of the method of making the fleece liner component of the footwear article of the invention.  
         [0015]    [0015]FIG. 2 is a generally perspective, diagrammatic view illustrating the next step in one form of the method of making the fleece liner component of the footwear article of the invention.  
         [0016]    [0016]FIG. 3 is a generally perspective view of the fleece liner component of the footwear article of the invention.  
         [0017]    [0017]FIG. 4 is a greatly enlarged, cross-sectional view taken along lines  4 - 4  of FIG. 3.  
         [0018]    [0018]FIG. 5 is an enlarged, fragmentary, cross-sectional, illustrative view showing one of the steps in the method of making the footwear article of the invention wherein the precursor footwear article is heated and compressed.  
         [0019]    [0019]FIG. 6 is a top plan view of one form of the footwear article of the invention.  
         [0020]    [0020]FIG. 7 is an enlarged, cross-sectional view taken along lines  7 - 7  of FIG. 6. 
     
    
     DESCRIPTION OF THE INVENTION  
       [0021]    Referring to the drawings and particularly to FIGS. 1 through 4, one form of the fleece liner component of article of apparel of the present invention and the method of making the same is there illustrated. As depicted in FIG. 3, the fleece liner here comprises a bonded assemblage made up of an inner layer of a conventional, commercially available fleece material. While several commercially available materials are suitable for use in constructing the fleece liner component, a fleece fabric made by Malden Mills Ind. Inc. of Lawrence, Mass. has proven to be ideal for use in accomplishing the method of the present invention. This material is a highly insulating fabric that is soft and both comfortable and durable in use. Additionally, the material includes an elastomeric component that is woven into the fabric so that the material stretches both lengthwise and crosswise thereby providing a fourway stretch making it extremely attractive for use in the present application.  
         [0022]    In constructing the fleece liner  14  of the character shown in FIG. 3, a first sheet or layer  16  of the fleece material is placed on the top surface of a rigid support such as an aluminum plate “P”. A thin layer of heat activated powdered adhesive “A” is then sprinkled on the upper surface of first layer to form a first precursor, coated component  16 . Next, a second sheet or layer  18  of fleece material is laid over first precursor, coated component,  16  in a manner shown in FIG. 2 to form the unbonded assemblage  20 . Assemblage  20  is then uniquely bonded together into the general configuration of a sock using a strategically formed, heated die  22  of the general character shown in FIG. 2. While several heat activated adhesives can be used in the construction of the fleece liner component  14 , an adhesive sold by EMS-Chemie (North America), Inc. of Sumpter, S.C. under the name and style GRILTEX D-P160400 has proven satisfactory for this purpose. It is to be noted that the usual prior art method of constructing articles of apparel using sheets of this type of fleece fabric involves first cutting the sheets of fabric into the desired configuration and then interconnecting the sheets using conventional sewing techniques. However, sewing the seams in the traditional manner undesirably forms welts on the assembled article that are objectionable in apparel such as socks and gloves. Because of this substantial drawback of the prior art material joining techniques, it was necessary to develop the novel bonding method of the present invention for assembling the fleece components to form the inner liner component of the article of apparel.  
         [0023]    In accordance with one form of the method of the invention for constructing the fleece liner  14 , the die  22  is used to heat the unbonded assemblage along a line “L” defining an open ended area that corresponds to the sock shape of the fleece liner. More particularly, the die heats the unbonded assemblage along the line of the die so as to controllably bond together the fibrils of the fleece material that are disposed beneath the die. In accomplishing the method of the invention, the die is held in a suitable press of a character well understood by those skilled in the art (not shown) and is heated to a temperature of between about 350 and about 450 degrees Fahrenheit, which is slightly above the softening point of the adhesive. When the heated die is brought into pressural engagement with the assemblage  20 , the discrete particles of the adhesive which have been randomly deposited onto the sheet  16  melt in a manner to strategically fuse together the fibrils  25  of the fleece material that are located beneath the heated die along line “L”. These bonded fibrils define the margin of the bonded liner (see FIG. 4). During this bonding step, the pressure exerted on the die by the press is preferably between about 40 psi and about 60 psi. After the edge fibril-bonding step has been completed, the particles of adhesive that were not activated during the bonding process are removed by shaking or tumbling the liner component  14 . This done, the first and second precursor components that have been bonded together along the desired bond line are suitably trimmed to define a clean, well-defined margin. Due to the nature of the fibril bond line formed in accordance with the novel method of the invention thus described, the edges of the trimmed assemblage which forms the fleece liner  14  is supple and uniquely exhibits almost no undesirable seam welt.  
         [0024]    Forming an important component of the sock construction  28  of the present invention shown in FIG. 6 of the drawings is a thin, pliant bladder  30  that is constructed from a waterproof, breathable material, such as polyurethane sheet. The polyurethane sheet can be of various thicknesses as, for example, between about 1.0 mils and about 3.0 mils. As illustrated in FIG. 7, bladder  30 , which includes an inner surface  30   a  that has been coated with a heat activated adhesive “A” and an outer surface  30   b  that has also been coated with a heat activated adhesive “A”, has the unique capability of generally conforming to the contours of the human foot and leg so that it can be comfortably worn inside a boot or shoe.  
         [0025]    Bonded to the inner surface  30   a  of the elastomeric bladder is the previously discussed fleece liner  14 . The article of the invention also includes an outer sock  34  that is bonded to the outer surface  30   b , The details of the construction of outer sock  34  will presently be described. While several heat activated adhesives can be used in the accomplishment of the method of the present invention, a hot melt adhesive in powder form sold by EMS-Chemie (North America), Inc. of Sumpter, S.C. under the name and style GRILTEX D-P160400 has proven satisfactory for this purpose.  
         [0026]    The thin, pliant, thermoplastic material from which the waterproof, breathable bladder is made is of a character that will prevent penetration of liquid water while at the same time permitting free passage of moisture vapor such as perspiration. This material can be polyurethane sometimes described as thermoplastic polyurethane. A suitable material of this type is sold by The Dow Chemical Company. Other suitable materials include elastomers made from polyesters, copolyesters, polyamides, cellulose derivatives, polyacrylic acid and its holologs, natural or synthetic rubber with hydrophilic impurities, copolyozamides, polyureas, polyelectrolytes, polyphosphates, polyvinylamid, polyvinylalcohol, polyether, and copolymers thereof, polythioether, polythioether-polyether, copolyepichlorohydrinether, polysulphosphates, copolyester-ether and derivatives or mixtures thereof and film materials made by W. L. Gore and Associates, called Goretex that incorporate The DuPont Company&#39;s Teflon® polytetraflouroethylene.  
         [0027]    The construction of the waterproof, breathable bladder  30  in accordance with one form of the method of the invention is accomplished by first coating both sides of a sheet of the thin, pliant bladder membrane with a light coating of the hot melt adhesive “A” to form a precursor, coated membrane. Next, the precursor, coated membrane is heated to a temperature slightly above the softening point of the adhesive, thereby causing the discrete particles of the adhesive which have been randomly deposited onto the bladder to fuse to the surface of the bladder material to form a coated membrane. Reference should be made to incorporated-by-reference U.S. Pat. Nos. 5,402,540, 5,655,226 and 5,483,703 for a more detailed description of this adhesive deposition process.  
         [0028]    The next step in the method of the invention for constructing the waterproof, breathable bladder is to overlay two sheets of the previously described-coated membrane and then to define on the membrane a line circumscribing the boundary of the bladder. This done, the sheets of coated membrane are heated along the boundary line to a temperature sufficient to sealably bond the membranes together along the boundary line. This heating-fusion step can be accomplished in several ways well known to those skilled in the art, including the techniques described in the incorporated by reference U.S. Pat. Nos. 5,402,540, 5,655,226 and 5,483,703. The heating-fusion step produces a bladder having an extremity-receiving portion that is in the general shape of the wearer&#39;s extremity, in this instance of the wearer&#39;s foot.  
         [0029]    The next step in the method of the invention is to place the fleece liner  14  over a generally foot-shaped, approximately {fraction (1/32)} inch thick, generally planar mandrel  36  having smooth outer surfaces (see FIG. 5). The fleece liner  14 , which has inner and outer surfaces  14   a  and  14   b  (FIG. 5) is placed over the mandrel so that inner surface  14   a  thereof is disposed in engagement with the faces  36   a  of mandrel  36 .  
         [0030]    After fleece liner  14  has been placed over mandrel  36  and smoothed out so that its inner surface is in close engagement with the faces of the mandrel, a first assemblage is formed by carefully placing bladder  30  over the assemblage of the fleece liner  14  and mandrel  36 . This done, bladder is smoothed so that the inner surface of the bladder is in close engagement with the outer surface of the fleece liner. Next, the precursor assembly is formed by carefully placing the outer fabric sock  34  over the first assemblage. This done, the outer fabric sock  34  is smoothed so that the inner surface thereof is in close engagement with the outer surface of the bladder  30 . Fabric sock  34  preferably comprises a knit sock that includes stretch fibers such as those sold by DuPont under the name and style LYCRA™ Spandex. Alternatively, sock  34  can comprise a conventional cut and sewn sock component. Reference should be made to the incorporated by reference U.S. Pat. Nos. 5,483,703, 5,655,226 and 5,483,703 for a more complete description of the mandrel  36  and the techniques for the construction of the precursor assembly.  
         [0031]    The precursor assembly formed in the manner described in the preceding paragraph, which comprises the bonded together fleece liner  14 , the bladder  30  and the outer sock  34  is then heated and compressed in the manner illustrated in FIG. 5 and more fully described in the incorporated by reference U.S. Pat. Nos. 5,655,226 and 5,483,703 to form the finished article. Briefly, this step is accomplished by placing the mandrel, upon which the precursor assembly is mounted, between two platens “P” that can be controllably heated to a temperature between about 260° F. and about 390° F. and urged at a pressure of between about 5 pounds per square inch and about 20 pounds per square inch together. During this temperature-pressure step, the polymer of the adhesive is bonded and cross-linked making a permanent, waterproof bond of the fleece liner  14  to the inside of the bladder and the outer sock  34  to the other side of the bladder. During this important temperature-pressure step, the bonded joint between the fleece layers  16  and  18  is reheated and securely bonded along the margin of the fleece liner to the bladder. During this bonding step the bonded joint uniquely tends to smooth out so that it is virtually unnoticeable to the user when the article of the invention is worn.  
         [0032]    After completion of the heating and compression step, the precursor assembly is removed from the press and allowed to cool thoroughly prior to doffing the completed waterproof footwear article from the mandrel. When removed from the mandrel, the footwear article is generally planar in shape and in one form of the invention, the article may be stitched along the margin of the bladder and the cuff. In use, when the foot is inserted into the open cuff of the article, the foot-engaging portion of the sock will neatly and smoothly conform to the shape of the wearer&#39;s foot.  
         [0033]    Having now described the invention in detail in accordance with the requirements of the patent statutes, those skilled in this art will have no difficulty in making changes and modifications in the individual parts or their relative assembly in order to meet specific requirements or conditions. Such changes and modifications may be made without departing from the scope and spirit of the invention, as set forth in the following documents.