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CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a divisional of U.S. patent application Ser. No. 14/221,317, filed on Mar. 21, 2014, the entire disclosure of which is hereby incorporated herein by reference in their entirety. 
     
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
       [0002]    N/A 
       BACKGROUND OF THE INVENTION 
       [0003]    1. Field of the Invention 
         [0004]    The present invention generally relates window treatment components and more specifically to a light blocking side valance or trim piece for use in conjunction with any type of window treatment. 
         [0005]    2. Description of Related Art 
         [0006]    Window treatments such as a slat blinds, venetian blinds, mini blinds, roller blinds, blackout shades, roman shades and the like are useful for providing privacy and blocking incoming light from a window. However, the complex mounting hardware and actuators needed for the window treatment to operate effectively typically requires the shade portion of the treatment to be somewhat narrower than the actual window opening in which the treatment is installed. For example, in the case of a typical roller shade, mounting brackets must be secured at the top of the window opening and protrude out into the opening at least ½″ on each side. Thus, in order for the roller blind to fit into the bracket and function properly, the shade is offset from either side of the window opening, leaving at least a ½″ edge gap through which unwanted light can pass through. The same problem is true for venetian blinds, roman shades, and other window treatments where the mounting hardware is placed inside the window opening (typically at the top edge of the opening). The gap at either side may be even more significant if the window treatment includes complex or large actuators such as turning rods, cords, and the like that require space accommodations. The resultant edge gap not only allows unwanted light to leak through but it also can result in a window treatment that appears unfinished or otherwise unsightly. Accordingly, there is a need in the art to provide a means to block unwanted light from leaking through at the sides of the window treatment while also maintaining a cohesive and attractive look. 
         [0007]    Some attempts have been made to fill the space or gap at the edge of the windows left by window treatments; however, none are versatile enough to be used with any type of window treatment and installation configuration. 
         [0008]    For example, U.S. Patent Application Publication No. 2013/0048230 to Marocco describes a window opening space filler used to adjust the window opening width to accommodate standard sized blinds in otherwise larger window openings. The filler includes a bracket piece affixed to the window opening and a filler member that attaches to the bracket piece and extends into the window opening so the user can reduce the width of the window opening at the side or edge thereof. The device is designed so the blind rides behind the filler member. The disadvantage of this arrangement is that the filler device requires two pieces and is completely visible because the blind rides behind the member. Further, only certain types of blinds such as roller blinds can be accommodated by the filler member without snagging because the blind rides behind the extended filler member. Multi-slat blinds will not function properly with this configuration because they do not have sufficient space behind the blind to rotate. Further still, because the blind rides behind the filler member, the blind will have a tendency to sway back toward the window which can again cause an edge gap that allows light to pass through. 
         [0009]    U.S. Patent Application Publication No. 2012/0012261 to Santoro et al. describes a window shade assembly having a two-part side channel system including a side channel attachment piece and a trim piece that is received in a slot on the attachment piece. The shade is received in a cavity created by the two pieces and slides up and down therein. The device is designed to retain the blind so that it doesn&#39;t sway from front to back inside the window and is not necessarily designed to block light at the side edges. More importantly, because the blind must ride inside the small cavity between the attachment piece and the trim piece, the side channel can only accommodate roller blinds as slat or venetian blinds will not have sufficient space to rotate and open. 
         [0010]    Accordingly, there is a significant need in the art for a light blocking solution that can be used with any type of blind in an aesthetically pleasing manner. It is, therefore, to the effective resolution of the aforementioned problems and shortcomings of the prior art that the present invention is directed. However, in view of the window treatment components in existence at the time of the present invention, it was not obvious to those persons of ordinary skill in the pertinent art as to how the identified needs could be fulfilled in an advantageous manner. 
       SUMMARY OF THE INVENTION 
       [0011]    The present invention is a light-blocking device for a window treatment to fill gaps on either side of the window treatment and to retain the window treatment at a distance spaced away from the window. The device is configured as a side valance or trim piece comprising an L-shaped member having a mounting face and a retaining face, the retaining face extending substantially perpendicular from the mounting face. The side valance may be constructed as an extrusion of any length desired. At least one frangible width adjustment notch is disposed lengthwise along the retaining face for adjusting the width of the device by breaking it along the desired notch. The mounting face is attached to a side of a window opening such that the retaining face extends outwardly from the side of the window opening to block light and retain the window treatment. When installed in a window opening, the retaining face is configured to be disposed between the window treatment and the window to keep the treatment away from the wall while also closing the gaps between the window opening and the edges of the window treatment. The length and width adjustability allows the side valance to be used for virtually any window treatment installation and configuration. 
         [0012]    In some embodiments, the side valance includes at least one frangible length adjustment notch disposed transversely across the valance similar to the width adjustment  20  notches but allowing the user to adjust the length of the piece to fit a wide variety of window openings. In some embodiments, a strip of protective material is disposed on an interior aspect of the side valance where the mounting face and the retaining face meet, in order to protect the window treatment as it moves up and down along the device. 
         [0013]    Accordingly, it is an object of the present invention to provide a device that fills the gap commonly found between the sides of a window opening and a window treatment to prevent unwanted light from passing through the gap. 
         [0014]    It is another object of the present invention to provide a device that retains a window treatment and spaces it away from the window for optimal stability, functionality, and aesthetics. 
         [0015]    It is another object of the present invention to provide a gap filling, light-blocking, and retaining device for window treatments that can be used for any style of window treatment including roller blinds, roman shades, slat blinds, and the like without the need to reconfigure or rearrange the components of the window treatment. 
         [0016]    It is another object of the present invention to provide a gap-filling, light-blocking device for window treatments that is adjustable in both length and width to accommodate the parameters of virtually any window treatment installation. 
         [0017]    It is another object of the present invention to provide a gap-fill, light-blocking device for window treatments that can be retrofitted into existing window treatment installations easily and quickly. 
         [0018]    With the foregoing and other objects in view, there is provided, a method of preventing light from passing through a gap between a window frame and a window treatment disposed in the window frame, the window frame having a window opening and vertical sides, the method including the steps of providing an L-shaped light-blocking device with a mounting face, a retaining face extending substantially perpendicular to the mounting face, and at least one frangible width adjustment notch disposed lengthwise along the retaining face, and attaching the mounting face to one of the vertical sides of the window frame to have the retaining face extend from the vertical side between the window treatment and the window opening and block at least some light passing between the window frame and the window treatment. 
         [0019]    With the objects in view, there is also provided a method of preventing light from passing through a gap between a window frame and a window treatment disposed in the window frame, the window frame having a window opening and vertical sides, the method including the steps of providing a pair of L-shaped light-blocking devices each with a mounting face, a retaining face extending substantially perpendicular to the mounting face, and at least one frangible width adjustment notch disposed lengthwise along the retaining face, and attaching the mounting face of each of the light-blocking devices to one of the vertical sides of the window frame to have the retaining face respectively extend from the vertical side between the window treatment and the window opening and block at least some light passing between the window frame and the window treatment. 
         [0020]    In accordance with another mode, the light-blocking device has a longitudinal extent, a transverse extent, and at least one frangible length adjustment notch disposed across at least a portion of the transverse extent. 
         [0021]    In accordance with a further mode, each of the light-blocking devices has a longitudinal extent, a transverse extent and at least one frangible length adjustment notch disposed across at least a portion of the transverse extent. 
         [0022]    In accordance with an added mode, the mounting face and the retaining face meet at a corner having an interior aspect and further comprising a strip of protective material disposed on the interior aspect of the corner. 
         [0023]    In accordance with an additional mode, the retaining face is wider than the mounting face. 
         [0024]    In accordance with yet another mode, the at least one frangible adjustment notch is substantially U-shaped and at least partially penetrates the retaining face. 
         [0025]    In accordance with yet a further mode, the at least one frangible length adjustment notch is disposed across at least one of the transverse extent of the mounting face, the transverse extent of the retaining face, and the transverse extent of both the mounting face and the retaining face. 
         [0026]    In accordance with yet an added mode, the at least one frangible adjustment notch is formed to break along the notch when a breaking force is applied at the retaining face. 
         [0027]    In accordance with yet an additional mode, the attaching step is performed by attaching the mounting face to one of the vertical sides of the window frame to have the retaining face extend from the vertical side between the window treatment and the window opening and block at least some light passing between the window frame and the window treatment and retain the window treatment at the window frame. 
         [0028]    In accordance with again another mode, there is provided the step of breaking the light-blocking device along the at least one frangible width adjustment notch to reduce a width of the retaining face. 
         [0029]    In accordance with again a further mode, there is provided the step of breaking the light-blocking device along the at least one frangible length adjustment notch to adjust a length of the device to fit the vertical side of the window frame. 
         [0030]    In accordance with again an added mode, two of the light-blocking devices are provided and the mounting face of each of the light-blocking devices is attached to one of the vertical sides of the window frame to have the retaining face respectively extend from the vertical side between the window treatment and the window opening and block at least some light passing between the window frame and the window treatment. 
         [0031]    In accordance with a concomitant mode, there is provided at least one of the steps of breaking the light-blocking device along the at least one frangible width adjustment notch to reduce a width of the retaining face and breaking the light-blocking device along the at least one frangible length adjustment notch to adjust a length of the device to fit the vertical side of the window frame. 
         [0032]    In accordance with these and other objects that will become apparent hereinafter, the instant invention will now be described with particular reference to the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0033]      FIG. 1  is a front perspective view of one embodiment of the side valance of the present invention having width adjustment features; 
           [0034]      FIG. 2  is a front perspective view of another embodiment of the side valance of the present invention having a length and width adjustment features; 
           [0035]      FIG. 3  is an end view of the side valance of the present invention showing the width adjustment feature; 
           [0036]      FIG. 3A  is a close-up view of the width adjustment features shown in  FIG. 3 ; 
           [0037]      FIG. 4  is another perspective view of the side valance of the present invention; and 
           [0038]      FIG. 5  shows the side valance in use with an exemplary window treatment. 
       
    
    
     DETAILED DESCRIPTION 
       [0039]      FIG. 1  is a front perspective view of one embodiment of the side valance  10  of the present invention. Side valance  10  is designed as a trim piece device to block light between the edge of a window treatment and a window opening and retain the window treatment away from the window. Side valance  10  is generally configured as an L-shaped member of any desired length and width comprising a mounting face  11  and a retaining face  12  wherein the retaining face  12  is perpendicular to the mounting face  11 . In some embodiments, the mounting face  11  and retaining  12  are generally planar rectangular bodies and the two faces  11  and  12  meet at corner  13  such that the retaining face extends from corner  13 , terminating at outer edge  121 . An interior aspect of corner  13  may be filled with a protective material  14  such as a felt, rubber, or other soft substance to prevent damage to the window treatment as further described here. 
         [0040]    In some embodiments, the retaining face  12  is somewhat wider than the mounting face  11 . Optionally provided lengthwise along the retaining face  12  are one or more frangible width adjustment notches  15 . Width adjustment notches  15  are disposed at predetermined locations on the retaining face  12  and allow for adjustment of the width of the retaining face  12 . Adjustment is accomplished by applying force to the retaining face  12  such that it breaks or snaps off at the desired width adjustment notch  15 . This obviates the need to use a saw or power tool to cut the side valance  10  down to fit the particular parameters of an installation.  FIG. 2  is a perspective view of another embodiment of the side valance  10 . Here, the valance  10  further includes one or more length adjustment notches  16  disposed transversely across the side valance toward one end. These length adjustment notches  16  allow for adjustment of the length of the side valance by applying force to the end of the side valance  10  and breaking or snapping it at the desired notch  16 . The depicted embodiments shown two width adjustment notches  15  and two length adjustment notches  16 ; however, any desired number of notches can be provided spaced apart at any desired increment. 
         [0041]      FIG. 3  is an end view of the side valance  10  again shown the mounting face  11  and retaining face  12 . Here, corner  13  is shown as having a relatively rounded shape with the interior aspect including protective material  14 . The profile of width adjustment notches  15  can be seen in  FIG. 3  and more easily in close-up  FIG. 3A  as substantially U-shaped grooves running lengthwise along the side valance  10 . In a preferred embodiment, the width adjustment notches  15  partially penetrate the surface of the retaining face  12  so that the valance  10  is easily frangible at the notches to provide a clean break and resultant edge. The length adjustment notches  16  shown in  FIG. 2  may be similarly configured. It is appreciated that the notches  15  and  16  could be disposed on either side of the side valance  10 . Also seen in the end view is protective material  14  disposed on the interior aspect of the corner  13  where the two faces  11  and  12  meet. The protective material preferably runs along the entire length of the side valance  10 . 
         [0042]      FIG. 4  shows one embodiment of the side valance  10  in full view. From here it can be seen that side valance  10  comprises an extruded member of any desired length or dimension. The side valance  10  can be constructed of any suitable opaque light-blocking material such as metal, plastic, wood, or combinations thereof and it may be pre-painted a desired color or may be of such a material that is suitably paintable. The dimensions of the side valance are not limiting, however by way of example, a standard side valance  10  may be 60 inches long and have a ½″ wide mounting face  11  and a 2″ wide retaining face  12 . In this example, the width adjustment notches  15  may be located such that the retaining face  12  can be adjusted to a width of ½″ and  1 ″ depending on which width adjustment notch  15  is used as a break point. In this configuration the notches are ½″ apart with the outermost notch ½″ from the outer edge  121  of the retaining face  12 . The length adjustment notches  16  can be at any desired increment such as 12″ to allow the 60 inch side valance to be adjusted to 48″, 36″, 24″ and so on. In another example, the length of the side valance  10  may be 72 inches and adjustable by length adjustment notches  16  to 60″, 48″, and 36″. 
         [0043]      FIG. 5  depicts one application of the side valance of the present invention in use with a window treatment to block light from passing through at the sides of the window treatment. Here it can be seen that two side valances  10  are employed and attached to either side of a window opening  20  that has a blind  30  disposed therein. The mounting face  11  of the side valances  10  is attached to the side walls  21  and  22  of the window opening  20 , respectively by known means such as a screw, nail, rivet, adhesive, double-sided tape, or the like. The side valances  10  are oriented such that once attached to the window opening, the retaining face  12  extends slightly into the window opening creating a light blocking and retaining trim feature for the blind  30 . In a preferred embodiment, the side valance  10  is such that the retaining face  12  is offset inside the window opening. The blind  30  is installed and oriented such that it rides on the outside of the retaining face  12  such that the retaining face  12  is disposed between the window  40  and the blind  30 . The protective material  14  prevents damage to the blind  30  from repeated reciprocation over the side valance  10 . As such, the side valance  10  is dual purpose by, primarily, filling the gaps on either side of the blind  30  to prevent light from passing through and, secondarily, by retaining the blind  30  a fixed distance away from the window  40  which prevents the blind  30  from swaying back toward the window. This retaining feature can be helpful with certain window treatments such as blackout shades because it is desired to maintain sufficient distance from the window for optimal light blocking. It is further apparent that because the retaining face  12  is disposed behind the blind  30 , the side valance  10  will not interrupt the operation of any type of blind  30  that is utilized whether it be a roller blind, slat blind, roman shade, mini blinds, faux wood and wood, roller shades and roman shades, pleated and honeycomb shades, woven wood/bamboo blinds, window shadings, panel tracks, and vertical blinds. Significantly, because the blind  30  rides in front of the retaining face  12 , it can move freely up and down and the blind&#39;s slats, if applicable, are free to rotate in any direction as desired. This is a substantial improvement over side channels known in the art that can only be used with roller blinds that have a flat, planar shade. It is further appreciated that the width and length adjustment notches are very useful in fine-tuning the light blocking ability of the side valance, as well as the aesthetics of the overall resultant installation. The width adjustment feature is particularly useful because it  10  allows the side valance  10  to accommodate different sized blinds and the parameters of virtually any window treatment installation. To the extent that the side valance  10  is visible, it can be painted or manufactured in a desired color to match the design of the window treatment or adjacent wall surfaces and other features. Further, the side valance  10  can be easily retrofitted to existing window treatment installations without the need to cut-down or otherwise reconfigure the window treatment itself. 
         [0044]    The instant invention has been shown and described herein in what is considered to be the most practical and preferred embodiments. It is recognized, however, that departures may be made therefrom within the scope of the invention and that obvious modifications will occur to a person skilled in the art.

Summary:
A method of preventing light from passing through a gap between a window frame and a window treatment disposed in the window frame, the window frame having a window opening and vertical sides includes the steps of providing an L-shaped light-blocking device with a mounting face, a retaining face extending substantially perpendicular to the mounting face, and at least one frangible width adjustment notch disposed lengthwise along the retaining face, and attaching the mounting face to one of the vertical sides of the window frame to have the retaining face extend from the vertical side between the window treatment and the window opening and block at least some light passing between the window frame and the window treatment.