Abstract:
A radio-frequency identification (RFID) label carries an embedded RFID antenna and is capable of being affixed to a package or label. The RFID enabled label includes a bottom portion and an RFID flap that includes a first portion attached to the bottom portion and a second portion that carries the RFID antenna. The RFID flap can be placed in a first position in which the second portion carrying the RFID antenna lies adjacent to the bottom portion, such that the RFID enabled label can be used in conjunction with a printer. The RFID flap is put into a second position in which the second portion carrying the RFID antenna is displace from the bottom portion. Displacing the RFID antenna from the bottom portion results in the RFID antenna being displace from the package or surface to which the bottom portion is affixed, allowing the RFID antenna to operate without interference from the package or surface.

Description:
CROSS-REFERENCE TO RELATED APPLICATION(S)  
       [0001]     This application claims priority of U.S. provisional patent application Ser. No. 60/841,154 filed on Aug. 30, 2006. 
     
    
     BACKGROUND  
       [0002]     The present invention relates to Radio Frequency Identification (RFID) antennas, and in particular to labels enabled with RFID antennas.  
         [0003]     RFID is an automatic identification method that stores and remotely retrieves data using devices known as RFID tags or transponders. Typically, RFID tags contain silicon chips and antennas that enable them to receive and respond to radio-frequency queries from an RFID transceiver. Passive tags require no internal power source, whereas active tags require a power source.  
         [0004]     RFID tags are often envisioned as a replacement for Universal Product Code (UPC) or European Article Number (EAN) barcodes, in which RFID tags can be used to quickly and easily track products and inventory. However, high cost and technical difficulties associated with adhering RFID tags to products and packages has limited the wide-spread use of RFID tags. For example, RFID tags affixed to metal surfaces exhibit poor performance.  
         [0005]     It would therefore be desirable to produce a label having RFID technology wherein the label may be affixed to any type of packaging or material without adversely affecting the performance of the RFID tag. It would furthermore be beneficial to generate a low cost solution to this problem.  
       SUMMARY  
       [0006]     Described herein is a radio frequency identification (RFID) enabled label. The RFID label includes a bottom portion and an RFID flap having a first portion adhered to the bottom portion and a second portion. In a first position, both the first portion and the second portion are substantially adjacent to the bottom portion. In a second position, the second portion is displaced from the bottom portion such that an RFID antenna embedded within the second portion is displaced from a packaging or surface to which the RFID enabled label is affixed.  
         [0007]     In another aspect, a method of adhering a radio frequency identification (RFID) enabled label to a surface or package is described. The method includes providing the RFID enabled label to a printer in a first position, in which an RFID flap is positioned adjacent a bottom portion of the RFID enabled label. The method further includes applying the RFID enabled label to the surface by adhering the bottom portion of the RFID enabled label to the surface. The RFID enabled label is moved from the first position to a second position, in which the RFID flap is displaced from the bottom portion. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0008]      FIGS. 1A and 1B  are perspective views of an RFID enabled label with an RFID antenna located on an RFID flap.  
         [0009]      FIGS. 2A and 2B  are cross-sectional views of an embodiment of a RFID enabled label having a shrink-wrap polymer layer that is used to separate the RFID flap from the attached surface during a thermal printing process.  
         [0010]      FIGS. 3A and 3B  are cross-sectional views of another embodiment of a RFID label having a shrink-wrap polymer layer that is used to separate the RFID flap from the attached surface during a thermal printing process.  
         [0011]      FIGS. 4A-4C  are perspective views of a RFID label having a tab for mechanically separating the RFID flap from the attached surface.  
         [0012]      FIGS. 5A and 5B  are cross-sectional views of the RFID label shown in  FIGS. 4A and 4B .  
         [0013]      FIG. 6  is a perspective view of an alternative embodiment of a RFID label having a tab for mechanically separating the RFID flap from the attached surface. 
     
    
     DETAILED DESCRIPTION  
       [0014]      FIG. 1A  shows RFID enabled label (“label”)  10  with RFID flap  12  in a first position, in which RFID flap  12  is pressed flat against bottom portion  14  of label  10 .  FIG. 1B  shows label  10  with RFID flap  12  in a second (i.e, operational) position, in which RFID flap  12  is lifted away from bottom portion  14 . In this position, RFID chip and antenna  16  (hereinafter, “antenna  16 ”) is displaced geographically from bottom portion  14 . When label  10  is in the first position (i.e., when RFID flap  12  is down), the label may be placed in a typical printer that allows graphics or labels to be printed onto top surface  18 . When label  10  is in the second, operational position, bottom portion of label  10  can be affixed to a package or product without the package or product interfering with the read/write capabilities of antenna  16 .  
         [0015]      FIGS. 2A-6  illustrate a number of embodiments in which label  10  may be converted from a first, non-operation state ( FIG. 1A ) to an operational state ( FIG. 1B ).  
         [0016]      FIGS. 2A and 2B  are cross-sectional views of an embodiment of an RFID enabled label  10  taken along lines  2 A- 2 A and  2 B- 2 B of  FIG. 1 , respectively. RFID label  10  includes, but is not limited to, the following: RFID antenna  16 , top surface  18 , heat activated polymer  22 , flap-back face  26 , bonding layer  28  (indicated by x marks), carrier layer  30 , adhesive layer  32 , and backing paper  34 .  
         [0017]      FIG. 2A  shows RFID label  10  in a first, non-operational state in which RFID flap  12  has not yet been separated from the bottom portion of RFID label  10 . Top surface  18 , heat-activated polymer layer  22   a , RFID antenna  16 , and flap-back face  26  (to the right of point A) represent the layers that are included in RFID flap  12 . A first portion of carrier layer  30  is bonded to a portion of flap-back face  26  by bonding layer  28 . A second portion of carrier layer  30  is not bonded to flap-back face  26 , which allows RFID flap  12  to be separated from carrier layer  30 . Prior to affixing RFID label  10  to a surface, backing layer  34  is removed to expose adhesive layer  32 , which is then affixed to the desired surface.  
         [0018]     In the embodiment shown in  FIG. 2A , images (such as the barcode shown in  FIGS. 1A and 1B ) are transferred or printed on top surface  18  using, for example, thermal printing techniques. For instance, either direct thermal (DT) or transfer thermal (TT) printing techniques may be employed. Both techniques have the effect of generating a desired image on top surface  20 , and both techniques provide a necessary amount of heat to activate heat-activated polymer layer  22   a . As shown in this embodiment, heat-activated polymer layer  22  is located over point A, which represents the point where flap-back face  26  is no longer bonded to carrier layer  30  by bonding layer  28 . When thermal energy is provided to heat-activated polymer layer  22 , it causes the polymer to contract or shrink in size. The contracting of heat-activated polymer layer  22   a  causes flap back face  26  to pull away from carrier layer  30  in the non-bonded region as shown in  FIG. 2B . The result is the separation of RFID flap  12  from carrier layer  30  as shown in  FIG. 2B .  
         [0019]     As shown in  FIG. 2B , following the contraction of heat-activated polymer layer  22   a , antenna  16  is physically separated from the bottom portion of label  10 . Backing paper  34  is removed to expose adhesive layer  32 , allowing label  10  to be affixed to any material without the material interfering with the operation of antenna  16 . This is an improvement over prior art methods that required insulation of antenna  16  with plastic packaging to prevent interference. The plastic packaging prevented label  10  from being used in conjunction with a printer. The present invention allows RFID labels to be manufactured such that they are still compatible with commonly used printing techniques.  
         [0020]      FIGS. 3A and 3B  show another embodiment of the present invention, in which a heat-activated polymer layer  22   b  extends along the length of label  10 . This is in contrast with the embodiment of label  10  shown in  FIGS. 2A and 2B , in which heat-activated polymer layer  22   a  was located in a small region located above point A. As shown in  FIGS. 3A and 3B , label  10  includes top surface  18 , heat-activated polymer layer  22   b , RFID antenna  16 , flap-back face  26 , bonding layer  28  (indicated once again by the x&#39;s shown to the left of point A), carrier layer  30 , adhesive layer  32 , and backing paper  34 .  
         [0021]      FIG. 3A  shows RFID label  10  in a first state in which RFID flap  12  (as shown in  FIGS. 1A and 1B ) has not yet been separated from the bottom portion of RFID label  36 . Thermal energy provided by a thermal printer (or comparable device capable or providing the requisite thermal energy) causes heat-activated polymer layer  22   b  to contract, resulting in RFID flap  12  being pulled away from carrier layer  30  to the right of point A as shown in  FIG. 3B . Therefore,  FIG. 3B  shows label  10  in a second, operational state in which free space is created between antenna  16  and a material or package to which label  10  is affixed.  
         [0022]     In the embodiments shown in  FIGS. 2A-2B  and  3 A- 3 B, the size of RFID antenna  16  creates a small bump on the surface of RFID label  10 . The size of the bump can be minimized as desired by increasing or decreasing the thickness of flap-back face  26 , top surface  18 , or heat-activated polymer layer  22   a  or  22   b . For example, in one embodiment the size of the bump created by RFID antenna  16  may be minimized by creating a RFID antenna sized slot in flap-back face  26 , allowing RFID antenna  16  to be placed in the slot. Similarly, all layers shown in  FIGS. 2A-2B  and  3 A- 3 B may be adjusted as required to generated the desired geometry of label  10 .  
         [0023]      FIGS. 4A-4C  are perspective views of another embodiment of the present invention, in which RFID label  40  includes a tab for manually separating an RFID flap from a bottom surface or adhesion layer. In this embodiment, RFID label  40  includes printable surface (or top surface)  42 , RFID flap  44  (which houses RFID antenna  46 ), tab  48 , and bottom portion  50 . As discussed above, bottom portion  50  includes an adhesive layer that allows RFID label  40  to be affixed to a package or product. Creating space between RFID antenna  46  and the material to which RFID label  40  is affixed allows RFID antenna  46  to operate without interference from the material.  
         [0024]      FIG. 4A  shows a perspective view of RFID label  40  in a first state, in which RFID flap  44  is pressed against bottom portion  50 . In this first state, RFID label  40  may be used in conjunction with a standard printer, allowing images and graphics (such as the barcode shown in  FIG. 4A ) to be printed onto top surface  42 . Following printing (or comparable operations), a user mechanically separates RFID flap  44  from bottom surface  50  by pulling tab  48  in the direction indicated by arrow  51 .  
         [0025]      FIG. 4B  shows a perspective view of RFID label  40  in a second state, in which RFID flap  44  has been mechanically separated from bottom portion  50  by pulling on tab  48 . As shown in  FIG. 4B , pulling tab  48  creates physical separation between RFID antenna  46  and bottom portion  50 . In this state, RFID label  40  may be affixed to a product or package, without the product or package material interfering with RFID antenna  46 .  
         [0026]      FIG. 4C  shows a rotated perspective view of RFID label  40  shown in  FIG. 4B , in which RFID label  40  is in the second, operational position. As shown in this view, tab  48  is attached to the upper half of RFID flap  44 . This connection style allows tab  48  to be laid flat against bottom surface  50  during printing process (or comparable processes that required label  40  to be flat). Pulling tab  48  in the direction shown by arrow  51  causes RFID flap  44  to be separated from bottom portion  50 .  
         [0027]      FIGS. 5A and 5B  are cross-sectional views of RFID label  40  taken along lines  5 A- 5 A and  5 B- 5 B, respectively. RFID label  40  includes, but is not limited to, the following: printable surface (or top layer)  42 , RFID antenna  46 , flap-back face  52 , tab  48  connected to the top portion of flap-back face  52 , carrier layer  54 , adhesion layer  56 , and backing paper  58 . A portion of carrier layer  54  is bonded to a portion of flap back face  52  by bonding layer  59  (indicated by the area marked with “x”). Tab  48  is located on the right side of RFID label  40 , and is located between flap-back face  52  and carrier layer  54 .  FIG. 5A  shows RFID label  40  in a first position, with RFID flap  44  pressed flat against the bottom portion of RFID label  40 .  FIG. 5B  shows RFID label  40  in a second, or operation position, wherein RFID flap  44  is physically separated from the bottom portion of RFID label  40 .  
         [0028]     As shown in  FIG. 5A , RFID label  40  includes top (or printable) surface  42 , RFID antenna  46 , mechanical tab  48 , flap back face  52 , carrier layer  54 , adhesive layer  56  and backing paper  58 . Top surface  42  may be a printable surface that compatible with typical printers. RFID antenna is located between top surface  42  and flap back layer  52 . Bonding layer  59  (indicated by area marked by ‘x’) secures the portion of flap back layer  52  located to the left of point A to carrier layer  54 . To the right of point A, flap back layer  52  is not bonded to carrier layer  54 , allowing flap back layer  52  to be pulled away from carrier layer  54 .  
         [0029]     Mechanical tab  48  is folded between flap back layer  52  and carrier layer  54  when RFID label  40  is in a first, non-operational state. Mechanical tab  48  is bonded to a portion of flap back layer  52 , as indicated by bonding area  62  (marked with x&#39;s). In order to separate RFID flap  44  from carrier layer  54 , a user pulls mechanical tab  48  in a direction indicated by arrow  61 .  
         [0030]      FIG. 5B  shows RFID label  40  in the second or operational state, in which RFID flap  44  has been separated from carrier layer  54  by a user pulling mechanical tab  48  in the direction indicated by arrow  61 . Backing paper  58  is removed to expose adhesive layer  56 , allowing RFID label  40  to be affixed to a package or product. In one embodiment, mechanical tab  48  also includes an adhesive layer, allowing mechanical tab  48  to be secured to the package or product, thus maintaining RFID flap  44  in the operational position.  
         [0031]      FIG. 6  is a perspective view of RFID label  64  that includes top surface  66 , RFID flap  68 , bottom portion  70 , and mechanical portion  72 . RFID antenna (not shown) is located within RFID flap  68 . In contrast with  FIGS. 4A-4C  and  5 A- 5 B in which the mechanical tab was separate from bottom portion  70 , in this alternative embodiment mechanical tab  72  is formed from a portion of bottom portion  70 . That is, bottom portion (which includes a carrier layer and adhesive layer as shown in  FIGS. 5A and 5B ) is cut to form a mechanical tab that can be actuated in the direction indicated by arrow  74 . One end of mechanical tab  72  is once again affixed to RFID flap  68 , allowing RFID flap  68  to be separated from bottom portion  70  when mechanical tab is pulled in the direction indicated by arrow  74 . In this embodiment, because mechanical tab  72  is formed of bottom portion  70 , it includes an adhesive layer that can be used to adhere mechanical tab  72  to a package or product, thus maintaining RFID flap  68  in the operational position.  
         [0032]     The present invention therefore describes an RFID label that can be used in conjunction with a standard printer for printing a label or barcode onto the surface of the RFID label. An RFID flap that houses an RFID antenna can then be separated from the package or product to which the RFID label is affixed, either automatically by applying thermal energy to the RFID label, or mechanically by applying mechanical force to a tab. The separation created between the RFID antenna and the package or product to which the RFID label is affixed allows the RFID antenna to operate without interference from the package or product. This is particular useful in application in which the RFID label is affixed to metal packages or products. In addition, the description of steps employed to affix an RFID label to a package or surface does not imply an order in which the steps must be performed. For instance, in an exemplary embodiment an RFID label is affixed to the package or surface, followed by activation of the thermal-activated polymer layer or application of mechanical force if a mechanical tab is employed to separate the RFID flap from the bottom portion of the RFID label. In another exemplary embodiment, the RFID flap is separated from the bottom portion of the RFID label during printing to a top surface of the RFID label, in which heat supplied by a thermal printer is used to activate the thermally-activated polymer layer.  
         [0033]     Although the present invention has been described with reference to preferred embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention. In particular, the present invention has been described with respect to radio frequency identification (RFID) technology, but the benefits of the present invention would apply to other technology in which the performance of a component is negatively impacted by the presence of a material or surface to which it is adhered.