Abstract:
A marker for use on printed materials includes a hollow body containing an ink reservoir. One end of the hollow body has an opening in which is received a tip, one end of the tip being in contact with the ink in the ink reservoir. The opposite end of the tip has at least one relatively sharp edge. The tip is made of a porous material that transmits ink from the ink reservoir to the printed material at a desired rate of flow by means of capillary action.

Description:
RELATED APPLICATIONS  
       [0001]     This application is a divisional of U.S. application Ser. No. 10/976,635 titled “MARKER TIP,” filed Oct. 29, 2004, which application claims the benefit of U.S. Provisional Application No. 60/622,058, filed on Oct. 26, 2004, entitled “MARKER TIP,” which applications are assigned to the assignee of the present invention and the entire contents of which are incorporated herein by reference. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     The present invention relates to a marker that reduces smearing of ink when used on printed materials. Inkjet printers enjoy widespread use. They are inexpensive, flexible, and produce high quality images. However, some inks used in inkjet printing are not completely waterfast and are accordingly susceptible of smearing when manipulated after printing.  
         [0003]     Smearing is particularly pronounced when the text or image is handled or otherwise modified immediately after printing, when the inks used are still wet. However, even after the inkjet inks have dried, images and text are still subject to smearing, as the solvents typically used in highlighter inks may solubilize the inkjet inks, which are then smeared by the tip of the highlighter.  
         [0004]     Referring to  FIG. 1 , there is illustrated a typical prior art marker used for highlighting text or coloring images. The prior art marker  100  has a tip  102  with a distal end  104  that is relatively flat or which has a large radius. The large distal ends are often used to increase the amount of ink that may be applied to the media being written upon. As the tip  102  of the prior art marker  100  is drawn across the surface of a printed medium  106  in the direction of arrow  108 , a first portion  110  of the tip  102  transfers ink from the tip  102  of the marker to the medium  106 . The ink transferred from the first portion  110  of the tip  102  is generally sufficient to solubilize the inkjet inks that have been laid down on the medium  106 . Thereafter, a second portion of the tip  112  transfers additional ink from the tip  102  to the medium  106 , but also acts to scour or abrade the surface of the medium  106 . This scouring action is a result of the inherent abrasiveness of the material from which the tip  102  is made. In many cases, the tip  102  of a prior art marker  100  is made of a fibrous material such as felt or the like. The scouring action of the second portion  112  tends to smear the inks applied to medium  106 . Because of these limitations, there is a need for a marker having a tip that can apply a visually sufficient amount of ink to media printed with inkjet inks and other non-fast inks that avoids or limits smearing of the images.  
         [0005]     These and other objects, aspects, features and advantages of the present invention will become more fully apparent upon careful consideration of the following detailed description of some embodiments of the present invention and the accompanying drawings, which may be disproportionate for ease of understanding, wherein like structure and steps are referenced generally by corresponding numerals and indicators. The invention further provides methods and apparatus of varying scope.  
       BRIEF SUMMARY OF THE INVENTION  
       [0006]     The present invention satisfies the needs of the prior art by providing a marker constructed and arranged to apply sufficient ink to a medium without smearing the ink. The marker includes a hollow body that may be cylindrical or another useful or ergonomic shape. The body of the marker encloses an ink reservoir and has an opening in one end that communicates with the ink reservoir. A tip is inserted and retained in the opening of the marker body such that an upper, proximal end of the tip is in contact with the ink in the reservoir. A lower, distal end of the tip is has a narrow edge formed thereon for applying ink transmitted through the tip by means of capillary action to a medium. 
     
    
     DESCRIPTION OF THE DRAWINGS  
       [0007]      FIG. 1  is a schematic illustration of a prior art marker tip being drawn across a printed medium.  
         [0008]      FIG. 2  is a schematic illustration of the front of an embodiment of a marker tip of the present invention.  
         [0009]      FIG. 3  is a schematic illustration of the side of the embodiment of the marker tip of  FIG. 2 .  
         [0010]      FIG. 4  is a side schematic illustration of another embodiment of a marker tip according to the present invention.  
         [0011]      FIG. 5  is a front schematic illustration of the marker tip of  FIG. 4 .  
         [0012]      FIG. 6  is a side schematic illustration of yet another embodiment of a marker tip according to the present invention.  
         [0013]      FIG. 7  is a front schematic illustration of the marker tip of  FIG. 6 .  
         [0014]      FIG. 8  is a side schematic illustration of an embodiment of a marker tip according to the present invention that includes a ferrule.  
         [0015]      FIG. 9  is a front schematic illustration of the marker tip of  FIG. 8 . 
     
    
     DETAILED DESCRIPTION  
       [0016]     In the following detailed description of some embodiments of the present invention, reference is made to the accompanying drawings that form a part hereof and in which is shown, by way of illustration, specific embodiments in which the invention may be practiced. In the drawings, like numerals describe substantially similar components throughout the several views. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention. Other embodiments may be utilized and structural changes may be made without departing from the scope of the present invention. The following description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is defined only by the appended claims and equivalents thereof.  
         [0017]     A marker  10  according to the present invention overcomes the limitations of the prior art by providing a tip structure that provides sufficient ink to the surface of the media, without scouring the surface and smearing the images on the media. The marker  10  illustrated in  FIGS. 2 and 3  includes a tip  12  made of a relatively rigid and porous molded material. The material from which the tip  12  is fashioned may be molded into many desired shapes, preferably having smooth surfaces. In some embodiments, the tip  12  may be formed using a suitable machining process. The tip  12  is mounted in an end of a hollow tube  14  such that an upper end (not shown) of the tip  12  is received within the tube  14  and is in contact with ink contained in a reservoir (not shown) of ink within the tube  14 . Ink is conducted from the reservoir in the tube  14  through the body of the tip  12  to a distal end  16  of the tip  12 . Touching the distal end  16  of the tip  12  to media  11  allows ink to flow from the tip  12  onto the media  11 .  
         [0018]     The tip  12  of the marker  10  is in its base form, generally cylindrically or slightly frustoconical. A distal end  16  of the tip  12  is shaped by a pair of planar facets  13  that are formed into the tip  12  in a generally planar parallel relationship to one another and a bottom surface  15  that intersects the facets  13  in a substantially perpendicular manner. Accordingly, the distal end  16  of the tip  12  is generally rectangular in cross section and has relatively sharp edges  17 . The tip  12  is preferably fashioned of a moldable, smooth material, though in some embodiments, the tip  12  may be formed by cutting portions thereof away in a suitable machining process. The distal end  16  of tip  12  may be inclined in orientation with respect to an axis of the marker  12  to allow the marker  10  to be held in a more natural writing attitude by a user as can best be seen in  FIG. 3 .  
         [0019]     In use, the marker  10  is addressed to the media  11  such that one of the sharp edges  17  is addressed to the media  11  in substantially full linear contact. As the tip  12  is drawn across the media  11 , the capillary nature of the tip  12  dispenses ink form the tube  14  of the marker  12  onto the media  11 . Note that in order to maintain contact between the edge  17  of the tip  12  and the media  11 , the marker  10  is angled as shown in  FIG. 2 . In this manner, the total area of contact  20  between the tip  12  and the media  11  is minimized. Scouring, and subsequently smearing of images on the media  11 , is thereby reduced. The edges  17  of the distal end  16  of the tip  12  need not be perfectly linear. However, any radius incorporated into the edges  17  should be small enough to approximate a linear edge and yet have sufficient surface area to transmit ink at a desired rate from the tube  14  to the media  11  via capillary action. In one embodiment, the edges  17  of the tip  12  have a radius of no more than forty (40) thousandths of an inch. In another embodiment, the edges  17  of the tip  12  have a radius that is no more than twenty (20) thousandths of an inch.  
         [0020]      FIGS. 4 and 5  illustrate side and front views, respectively, of another embodiment of a marker  30  according to the present invention. Marker  30  includes a tube  32  that incorporates an ink reservoir (not shown) therein. A tip  34  is received and retained in an open end of tube  32  such that an upper end of tip  34  (not shown) is in contact with the ink in the ink reservoir within tube  32 . The tip  34  is preferably fashioned of a moldable, smooth material, though in some embodiments, the tip  34  may be formed by cutting portions thereof away in a suitable machining process. The basic shape of the tip  34  is generally cylindrical or slightly frustoconical and has a distal end  36  having a relatively sharp edge  38  that is defined by first and second facets  40 . These facets  40  may be planar or curvilinear, though in the illustrated embodiment, the facets  40  are shown as being planar. Note also that the sharp edge  38  may be linear as shown in the illustrated embodiments, but may also be curvilinear in shape, so long as it retains its “sharp” aspect. In one embodiment, the tip  34  has a complex shape in which facets  40  sharpen a taper begun by facets  40 .  
         [0021]     The edge  38  of the distal end  36  of the tip  34  need not be perfectly sharp. However, any radius incorporated into the edge  38  should be small enough to approximate a sharp linear, and in some embodiments a curvilinear, edge and yet have sufficient surface area to transmit ink at a desired rate from the tube  32  to the media (not shown) via capillary action. In one embodiment, the edge  38  of the tip  34  has a radius of no more than forty (40) thousandths of an inch. In another embodiment, the edge  38  of the tip  34  has a radius that is no more than twenty (20) thousandths of an inch. While the edge  38  is in the illustrated embodiments inclined with respect to an axis of symmetry of the tube  32  to facilitate an ergonomic grip while in use, the edge  38  may also be perpendicular to an axis of the tube  32 .  
         [0022]      FIGS. 6 and 7  illustrate side and front views, respectively, of yet another embodiment of a marker  50  of the present invention. Marker  50  includes a tube  52  that incorporates an ink reservoir (not shown) therein. A tip  54  is received and retained in an open end of tube  52  such that an upper end of tip  54  (not shown) is in contact with the ink in the ink reservoir within tube  52 . The tip  54  is preferably fashioned of a moldable, smooth material, though in some embodiments, the tip  54  may be formed by cutting portions thereof away in a suitable machining process. The basic shape of the tip  54  is generally cylindrical or slightly frustoconical. The distal end  56  of the tip  54  has a relatively sharp edge  58  defined by facets  60 .  
         [0023]     The edge  58  of the distal end  56  of the tip  54  need not be perfectly linear. However, any radius incorporated into the edge  58  should be small enough to approximate a linear edge and yet have sufficient surface area to transmit ink at a desired rate from the tube  52  to the media (not shown) via capillary action. In one embodiment, the edge  58  of the tip  54  has a radius of no more than forty (40) thousandths of an inch. In another embodiment, the edge  58  of the tip  54  has a radius that is no more than twenty (20) thousandths of an inch. While the edge  58  is in the illustrated embodiments inclined with respect to an axis of symmetry of the tube  52  to facilitate an ergonomic grip while in use, the edge  58  may also be perpendicular to an axis of the tube  52 .  
         [0024]      FIGS. 8 and 9  illustrate side and front views, respectively, of an embodiment of a marker  70  that includes a supporting ferrule. Marker  70  includes, like the previous embodiments, a tube  72  that incorporates an ink reservoir (not shown) therein. A tip  74  is received and retained in an open end of tube  72  such that an upper end of tip  74  (not shown) is in contact with the ink in the ink reservoir within tube  72 . A supporting ferrule  76  is formed around the top  74  such that only a radiused edge  80  of the tip  74  is exposed. The ferrule  76  stiffens the tip  74  and couples the tip  74  to the tube  72 .  
         [0025]     The edge  80  of the tip  74  is generally cylindrical in shape and presents a relatively small radius to a medium to which ink is to be applied. The radius of the edge  80  is sufficient to facilitate the transmission of ink through the tip  74  by capillary action to the media at a desired rate and without scouring the surface of the media. In one embodiment, the chord width of the portion of the cylindrical edge  80  of the tip  74  that contacts the media  10  during use is no more than forty (40) thousandths of an inch. In another embodiment, the chord width of the portion of the cylindrical edge  80  of the tip  74  that contacts the media  10  during use is no more than twenty (20) thousandths of an inch. While the edge  80  is in the illustrated embodiments inclined with respect to an axis of symmetry of the tube  72  to facilitate an ergonomic grip while in use, the edge  80  may also be perpendicular to an axis of the tube  72 .  
       CONCLUSION  
       [0026]     Although specific embodiments have been illustrated and described herein, it is manifestly intended that this invention be limited only by the following claims and equivalents thereof.