Patent Abstract:
A building panel includes a sheet of wood material having opposing surfaces and bounding edges. The sheet of wood material is encased by a coating of a mixture of pigments and polymeric resins electrostatically adhered to the opposing surfaces and edges, and cured.

Full Description:
RELATED APPLICATIONS 
       [0001]    This application is a continuation of U.S. application Ser. No. 11/869,429 filed Oct. 9, 2007 which is incorporated herein by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    This invention relates to wall panels. 
         [0003]    More particularly, the present invention relates to wood panels for use in buildings and a method by which they are employed. 
       BACKGROUND OF THE INVENTION 
       [0004]    In the field of building construction, a conventional building is typically constructed as a masonry structure, framework structure, or a combination of both. Masonry construction typically includes the erection of masonry walls of brick, block, or concrete. Frame construction includes the erection of a supporting framework of wood or metal for stability and strength. The structure defined by the framework is typically enclosed by sheathing. Sheathing consists of sheet material hung from the framework, typically on an outer surface thereof. Drywall or sheet rock is employed to finish the interior of the structure, and is typically hung from an inner surface of the framework. The materials used for sheet material include wood, metal, glass and plastic products. Upon assembly of the structure, additional procedures or treatments are required to enhance the aesthetics of the building and increase its durability and weathering ability. The treatments, such as the application of paint, water barriers and the like, can be costly and time consuming, but are necessary to protect the sheet material from the elements. 
         [0005]    While used extensively over the ages, these building types each have drawbacks. Masonry buildings are labor intensive and require a large amount of heavy materials. Frame buildings while lighter, still require a large amount of time for construction. Both of these building types require expensive materials and man hours of labor for construction as well as various additional steps, such as painting, for completion. 
         [0006]    The sheathing materials used include composite sheet material. For this specific application wood based sheets (lignocellulosic composites) are addressed. Wood based composite sheets include particle board, flake board, plywood and the like. Sheet material formed of wood products such as these use various binders to create a solid structure. 
         [0007]    Binder compositions which are used in making such composite wood sheets include phenol formaldehyde resins, urea formaldehyde resins and isocyanates. Each of these types of binders has its advantages and disadvantages. Phenolformaldehyde and urea-formaldehyde binders are relatively inexpensive and have high structural strength. Their disadvantages include emission of formaldehyde which can pose health risks and absorption of moisture. The emission of formaldehyde has been addressed to some extent by reformulating the binders to include a lower percentage of formaldehyde. While generally successful, the modification to the phenolformaldehyde and urea-formaldehyde binders also adversely impacts the structural strength of the final product. The other disadvantage of composite sheets made with these binders, moisture absorption, is more problematic. In humid and damp environments, composite wood sheets of this type can swell and distort causing many problems and reducing the life of the composite sheet. 
         [0008]    Isocyanate binders provide sheets with good structural strength and have no formaldehyde emissions. They tend to be more expensive, and have some processing difficulties. A specific problem in processing is that the isocyanate has a undesirably rapid reaction with water present in the wood material and any water present in the binder composition itself. This problem can be reduced by utilizing wood materials that have very low moisture content. To obtain wood materials having low moisture content, it is often necessary to dry the materials. This can substantially increase the cost of the final product, and more importantly, the dried wood material tends to absorb moisture and swell when the final product is used in humid environments. 
         [0009]    It would be highly advantageous, therefore, to remedy the foregoing and other deficiencies inherent in the prior art. 
         [0010]    An object of the present invention is to provide a panel for building construction. 
         [0011]    Another object of the present invention is to provide a panel system for building construction having moisture resistant characteristics. 
         [0012]    Yet another object of the present invention is to provide a method of using the panel for constructing building with weather withstanding ability. 
       SUMMARY OF THE INVENTION 
       [0013]    Briefly, to achieve the desired objects and advantages of the instant invention, a building panel is provided. The building panel includes a sheet of wood material having opposing surfaces and bounding edges. The sheet of wood material is encased by a coating of a mixture of pigments and polymeric resins electrostatically adhered to the opposing surfaces and edges, and cured. 
         [0014]    Also provided is a method of fabricating a building panel. The method includes forming a sheet of wood material, electrostatically adhering a mixture of pigments and polymeric resins to the sheet of wood material to completely encase the sheet of wood material in a moisture resistant coating, and curing the coating encasing the sheet of wood material. 
         [0015]    Additionally, the step of curing includes heating the sheet of wood material with the adhered mixture of pigments and polymeric resins with ultra-violet light. In a specific aspect, the method includes pre-heating the sheet of wood material with the adhered mixture of pigments and polymeric resins prior to heating with ultra-violet light. 
         [0016]    The step of forming a sheet of wood material includes the step of forming a sheet of composite wood material. A plurality of wood piece is provided and mixed with a resin binder. The mixed resin binder and wood pieces are formed in a sheet of wood material with heat and pressure. 
         [0017]    The step of forming the sheet of wood material can include cutting the sheet of wood material to pre-determined dimensions for a building construction prior to the steps of electrostatically adhering and curing. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0018]    Specific objects and advantages of the instant invention will become readily apparent to those skilled in the art from the following detailed description of a preferred embodiment thereof taken in conjunction with the drawings, in which: 
           [0019]      FIG. 1  is a cross sectional view of a panel according to the present invention; 
           [0020]      FIG. 2  is a plan view of a pre-cut panel according to the present invention; 
           [0021]      FIG. 3  is a is a simplified schematic illustration of an exterior wall panel fastened to a foundation; 
           [0022]      FIG. 4  is a perspective of panels used as exterior walls; 
           [0023]      FIG. 5  is a simplified top view of panels joined with a rebate joint; 
           [0024]      FIG. 6  is a simplified top view of panels joined with a mitered joint; 
           [0025]      FIG. 7  is a partial perspective view of panels joined as interior walls; 
           [0026]      FIG. 8  is a partial perspective view of panels joined as interior walls; 
           [0027]      FIG. 9  is a partial sectional side view of joined ceiling panels; 
           [0028]      FIG. 10  is a partial perspective view illustrating a truss on the ceiling panels; 
           [0029]      FIG. 11  is a top plan view of an interior wall box; and 
           [0030]      FIG. 12  is a top plan view of another interior wall box. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0031]    Turning now to the drawings in which like reference characters indicate corresponding elements throughout the several views, attention is first directed to  FIG. 1  which illustrate a sectional view of a panel according to the present invention, generally designated  10 . Panel  10  includes a wood composite sheet material  12  fabricated of myriad pieces of wood. Conventional composite wood sheet material includes particle board, flakeboard, plywood and the like. These wood pieces can be of various shapes and sizes and can be of newly acquired wood, recovered wood, or recycled wood materials. The composite wood sheet material is formed in a generally conventional manner. In this preferred embodiment, flakeboard is the composite sheet material of choice and will be described below. 
         [0032]    The fabrication of flake board includes providing flakes or pieces of wood material, generally of a substantially uniform size, mixed with a binder resin, and bonded together with pressure and heat. Most composite boards are produced by pressing a mat of resin intermixed parts flat in a heated press. Extruded boards are produced by forcing the resin imparted pieces between parallel heated rollers. Wood composite sheet material  12  is then cut to the desired dimensions, and can include shaped edges, such as bull nose, rebated joints, miters and the like, and openings such as for windows, doors, and the like. 
         [0033]    To complete panel  10 , wood composite sheet material  12  is then sealed against moisture and provided with a durable and esthetically pleasing surface. This is accomplished by providing a mixture of fine particles of pigment and polymeric resin. The powder is sprayed and adhered electrostatically to the surfaces of wood composite sheet material  12  to form panel  10 . Pre-heating sheet material  12  is preferably part of this process. Panel  10  is then heating in a curing oven utilizing UV radiation to fuse the powder into a strong adhering coating  14 . In this manner a composite wood sheet material  12  is formed into panel  10  capable of being subjected to the environment without adverse effects and eliminating moisture absorption. Additionally, further steps during construction are avoided, such as painting, weather proofing and the like. 
         [0034]    As can be seen with reference to  FIG. 2 , panel  10  can be pre-cut prior to formation of coating  14 . The desired edge shape, rebate joints, miter joints, and the like, and openings such as window and door openings are formed in composite wood sheet material  12 , so when coating  14  is formed, all surfaces, including edges have the coating thereon. 
         [0035]    Turning now to  FIGS. 3 and 4 , a method of constructing a building using panel  10  of the present invention is illustrated. A foundation  20  is first provided, and can be constructed in any known manner, such as concrete slab, wood platform, and the like. A sole plate  22  is laid on foundation  20 , and the pre-sized panels  10  are then erected and braced as exterior walls  24 . The foot edge of panels  10  are held in position by an angle iron  23  extending therealong and fastened to foundation  20 . Panels  10  used for exterior walls  24  of a building are preferably 1½ inches thick, and preferably measure  24  feet wide by 9 feet high. Battens  25  can be attached using fasteners such as screws and glued to the exterior surface of panels  10  used as exterior walls  24 . Battens  25  extend vertically and provide additional strength and permit attachment of siding if desired. The unique thickness and dimensions of panels  10  allow the construction of buildings capable of withstanding 200 mph winds. Additionally, since panels  10  have been pre-cut to the desired dimensions and with the desired openings such as for windows and doors prior to the completion of the panel fabricating process with the addition of coating  14 , all surface are coated and protected against the elements. 
         [0036]    Turning to  FIGS. 5 and 6 , panels  10  of exterior walls  24  are joined employing rebate joints ( FIG. 5 ) at perpendicular or end joined panels  10 , or mitered joints ( FIG. 6 ) at perpendicular or angled joined panels  10 . The joints are glued with an adhesive  16  and coupled using fasteners such as screws  18 . 
         [0037]    Once panels  10  for exterior walls  24  are in place, interior walls  27  are erected. Turning to  FIG. 7 , interior walls  27  are attached to exterior walls  24  or other interior walls  27  (as shown) using a rebate joint, fasteners such as screws, and an adhesive. Panels  10  used for interior walls  27  are preferably 1 inch in thickness. No headers are employed. Since all of the interior and exterior panels are cut prior to installation very little additional material removal is required. In this manner, the panels are finished with coating  14  protecting the composite wood sheet material  12  from adverse weather and in particular, moisture. Any additional cuts or removal of material will be finished by adding a pigment resin mixture, as in the coating, to the exposed edge. Still referring to  FIG. 7 , the foot edge of panels  10  of interior walls  27  are coupled to foundation  20  using any convenient means such as anchors but preferably a tapcon fastening  19  is employed. The edges of the interior walls can be shaped as desired, such as being radiused or the like for esthetic purposes. 
         [0038]    Referring to  FIG. 8 , angled interior walls are preferably joined with panels  10  of interior walls  27  joined to panels  10  of other interior walls  27  using rebate joints. Lesser angles can employ miter joints instead. 
         [0039]    Once interior walls  27  are positioned, ceiling panels  28  are laid over the top edges of exterior walls  24  and interior walls  27  and attached by a fastener such as screws and an adhesive. As can be seen in  FIG. 9 , panels  10  employed for ceiling panels  27  are joined by an angled tongue and groove joint  30  supported by a plate  32  fastened to each panel  10  by fasteners  33 . Plate  32  extends along and across joint  30  between ceiling panels  28 . With additional reference to  FIG. 10 , trusses  35  are then positioned on panels  10  used as ceiling panels  28  for the completion of a roof. Once ceiling panels  28  are in place and attached to exterior walls  24  and interior walls  27 , the bracing can be removed. 
         [0040]    Interior walls  27  can appear unsubstantial at interior openings such as doorways, archways and the like. This can be esthetically improved by boxing the opening as illustrated in  FIGS. 11 and 12 . With reference to  FIG. 11 , the end of an interior wall  27  terminates in a box  40  formed of four pieces  42   a,    42   b,    42   c,    42   d  of a panel  10 . The four pieces are joined using rebate joints as illustrated, with channels formed in pieces  42   a  and  42   c  for receiving the ends of pieces  42   b  and  42   d.  The pieces are fixed using an adhesive within the joint, and a fastener such as screws. Interior wall  27  terminates in a rebate joint with box  40 . An end of interior wall  40  is received in a channel formed in piece  42   d.  A door frame  45 , in this embodiment, is coupled to piece  42   b.  It will be understood that an identical box is formed on the opposite side of the door. It will also be understood that while interior wall  27  terminates centrally in piece  42   d,  interior wall  27  can terminate at or closer to either pieces  42   a  or  42   c.  It is also noted that corners of box  40  can be curved by providing curved edges to pieces  42   a  and  42   c.  A curved joint as illustrated can be employed on any joint in the building. 
         [0041]    Another embodiment of a box  40 ′ is illustrated with reference to  FIG. 12 . In this embodiment, only three pieces  42   a ′,  42   b ′ and  42   c ′ are required. The fourth side of box  40 ′ is provided by the terminating interior wall  27 ′. A door frame  45 ′ is attached to piece  42   c ′. As will be understood, opening such as archways will not employ doorframes and the like. 
         [0042]    Various changes and modifications to the embodiments herein chosen for purposes of illustration will readily occur to those skilled in the art. To the extent that such modifications and variations do not depart from the spirit of the invention, they are intended to be included within the scope thereof, which is assessed only by a fair interpretation of the following claims.

Technology Classification (CPC): 4