Abstract:
The present invention comprises a RFID signal distortion device which overcome the foregoing difficulties which have long since characterized the prior art. In accordance with the broader aspects of the invention the RFID device comprises multiple layers of substrates; wherein each substrate is adapted, when the RFID device is positioned substantially orthogonal to the transmitting plane of the RFID device, to distort data transmission from an RFID when the RFID is interrogated by an electric field or a magnetic field.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application is related to, claims the earliest available effective filing date(s) from (e.g., claims earliest available priority dates for other than provisional patent applications; claims benefits under 35 USC §119(e) for provisional patent applications), and incorporates by reference in its entirety all subject matter of the following listed application(s) (the “Related Applications”) to the extent such subject matter is not inconsistent herewith; the present application also claims the earliest available effective filing date(s) from, and also incorporates by reference in its entirety all subject matter of any and all parent, grandparent, great-grandparent, etc. applications of the Related Application(s) to the extent such subject matter is not inconsistent herewith. U.S. provisional patent application 61/589,382 entitled “Passive RFID Data Signal Distortion Device”, naming Kevin Correll, as inventor, filed 22 Jan. 2012. 
    
    
     BACKGROUND 
     1. Field of Use 
     This invention relates generally to intentional distortion of Radio Frequency Identification (RFID) devices, and more particularly to devices for preventing unauthorized electronic retrieval of personal information from identification cards, credit cards, and other RFID equipped cards. 
     2. Description of Prior Art (Background) 
     Radio Frequency Identification technologies, commonly referred to as RFID, utilize electronic signals to identify people and objects. In general, a RFID system comprises at least one microchip and an antenna, together referred to as an RFID transponder or tag, and at least one reader. The antenna enables the chip to electronically transmit identification data to the reader. The reader receives and converts the radio waves into digital information for further processing. 
     RFID systems are used in numerous industries, the most common being use of RFID systems for asset tracking purposes. Active RFID tags have their own transmitter and power source and are therefore used for tracking larger objects across greater distances. Passive RFID tags do not have either a power source or an antenna. Instead they simply reflect radio waves back to a reader associated with the transmission a of an electronic signal. Passive tags are therefore more limited in range. Examples of passive tag systems include tollbooth applications enabling a transponder on a vehicle to reflect a signal to a reader in the tollbooth and inventory tracking systems in retail stores that track inventory movement within the store and prevent theft of items from the store. 
     More recently RFID systems have been implemented into touchless express pay systems whereby payment can be made by simply waving a credit card or key fob in front of a reader. Although highly convenient, express pay systems incorporate the inherent danger that the associated account will be charged by accident or possibly charged without the owner&#39;s knowledge. Indeed, theft of credit or debit card information and identification has become rampant worldwide. Governments, companies, and consumers spend millions of dollars each year to prevent and pursue such thefts. 
     Nevertheless, recent developments in security technology still do not fully address potential security breaches of an RFID system; such as when an unauthorized RFID interrogation or reading device attempts to extract the RFID information, especially when a user or possessor of an RFID device is unsuspecting or not cognizant that the RFID device is being interrogated. Others have attempted solutions at blocking RFID devices to enhance privacy. 
     Prior art solutions typically involve a shielded wallet or bill-fold comprising a textile material having electromagnetic shielding incorporated therein. In other words, prior art solutions attempt to shield or block electromagnetic signals from reaching the RFID device. This approach often leads to bulky shielding solutions, such as, for example, cases made of aluminum. In addition, while aluminum is often used as electromagnetic shielding of an electric field it can fail to block a magnetic field. Other prior art solutions disclose lengths of electromagnetic shielding for electric fields but also fail to disclose layers of electromagnetic shielding wherein each layer of the electromagnetic field is adapted to block different types of electromagnetic fields due to different types of RFID data transfer, e.g., electric fields associated with RFID backscatter techniques and magnetic fields associated with RFID magnetic dipole antennas. In addition, prior art textile or fabric type shields are generally designed to block electromagnetic frequencies in the high megahertz (MHz) to gigahertz (GHz) range. However, mainstream RFID frequency ranges are on the order of below 150 kilohertz (KHz) for magnetic inductive coupling to about 15 MHz for inductive coupling and backscatter techniques. 
     Still other complex prior art solutions disclose an RFID card designed to radiate an interference pattern sufficient to disrupt or interfere with the data transmission of the RFID being interrogated. These solutions, aside from being expensive, require that the interfering RFID card radiate a pattern of sufficient strength and signal similarity with the interrogated RFID card in order to disrupt or interfere with the signal radiated by the interrogated RFID card. However, these types of solutions are comparatively expensive and require complex micro-circuitry. Moreover, each RFID card, or groups of RFID cards, requiring protection may need a separate interfering RFID matched to its specific type of data transmission. For example, a RFID card using electromagnetic backscatter techniques would need interfering RFID using similar techniques. Likewise, a RFID card using magnetic dipole antenna would require in interfering RFID card using similar magnetic dipole antenna techniques. It will be appreciated that this approach would be very cumbersome for the user to carry extra interfering RFID cards, in addition to the ones the user typically carries. It will also be appreciated that the user would likely be confused which interfering RFID card goes with which RFID card to be protected; particularly since the data communication type of RFID card, e.g., magnetic dipole or electromagnetic backscatter, is not readily apparent. 
     Shielding against low-frequency magnetic fields is, comparatively, not as easy as shielding against electric fields. The effectiveness of magnetic shielding depends on the type of material—its permeability, its thickness, and the frequencies involved. Due to its high relative permeability, steel is much more effective than aluminum and copper as a shield for low-frequency (roughly below 100 kHz) magnetic fields. At higher frequencies, however, aluminum and copper can be used as well. However, the magnetic shielding properties of these metals are quite ineffective at low frequencies. In general, the magnetic shielding provided by non-magnetic conductor depends upon random eddy currents induced in the non-magnetic conductor by the magnetic reader field and the subsequent random counter magnetic fields opposing the magnetic reader field. Better magnetic shields such as Mu-metal can be found for low-frequency magnetic shielding; but, Mu-metal is very fragile, relies on thickness or depth for its magnetic shielding; and can have severe degradation of its permeability, and hence, degradation of its effectiveness as a magnetic shield by mechanical shocks. Consequently, to be effective, Mu-metal solutions require bulky, difficult to handle, Mu-metal shielding. 
     BRIEF SUMMARY 
     The present invention comprises a RFID signal distortion device which overcome the foregoing difficulties which have long since characterized the prior art. In accordance with the broader aspects of the invention the RFID device comprises multiple layers of substrates; wherein each substrate is adapted, when the RFID device is positioned substantially orthogonal to the transmitting plane of the RFID device, to distort data transmission from an RFID when the RFID is interrogated by an electric field or a magnetic field. 
     According to this invention, a passive RFID data signal distortion device is provided. The device includes a first substrate having a top surface area adaptable to receive print media. The device also includes a bottom surface area having a plurality of magnetically receptive deposits for disruption of data transferred via magnetic induction. The device also includes a second substrate having an electric field disruption material; and an adhesive layer for bonding the bottom surface area of the first substrate to the second substrate. 
     The invention is also directed towards a passive RFID data signal distortion device. The device includes a first substrate having a top surface area adaptable to receive magnetically receptive ink printed as a message, artwork, or advertisement. The device also includes a second substrate comprising an electric field disruption material. The second substrate and the first substrate are bonded together by an adhesive layer. Optionally, the adhesive layer may contain metallic particles for disrupting either the electric field or magnetic field data transfer. 
     The invention is also directed towards a passive RFID data signal distortion device. The device includes a first substrate having a top surface area adaptable to receive print media. The print media includes a plurality of printed magnetically receptive deposits, wherein each of the printed magnetically receptive deposits comprises a layer thickness less than 20 microns thick. The spatial location of each of the plurality of printed magnetically receptive deposits is predetermined. Each of the plurality of printed magnetically receptive deposits includes magnetites; resin binders; and plastizers combined to form a laser printing toner composition. The device also includes a second substrate for disrupting or blocking electric fields or radio frequency transmissions. In addition, the spatial location of each of the plurality of printed magnetically receptive deposits may be predetermined according to an opposing magnetic field generated by the second substrate in response to an exterior magnetic field. In addition, the spatial location of each of the plurality of printed magnetically receptive deposits may also be predetermined according to a predetermined image. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a side perspective view of the portable RFID signal distortion device according to this invention; 
         FIG. 2  is a pictorial top view of the advertising/instruction layer of the invention shown in  FIG. 1 ; 
         FIG. 3  is a pictorial top view of the magnetic field interference layer of the invention shown in  FIG. 1 ; 
         FIG. 4  is a pictorial top view of the electric field interference layer of the invention shown in  FIG. 1 ; 
         FIG. 5  is a pictorial view of a billfold employing the invention shown in  FIG. 1  and  FIG. 6 ; 
         FIG. 6  is a side perspective view of an alternate embodiment of the portable RFID signal distortion device shown in  FIG. 1 ; 
         FIG. 7  is a pictorial top view of the print layer shown in  FIG. 6 ; 
         FIG. 8  is a pictorial bottom view of the print substrate shown in  FIG. 6  showing magnetically receptive deposits; 
         FIG. 9  is a pictorial bottom view of the radio signal substrate shown in  FIG. 6  showing partial adhesive layer; 
         FIG. 10  is a side perspective view of an alternate embodiment of the portable RFID signal distortion device shown in  FIG. 1 ; 
         FIG. 11  is a pictorial top view of the print layer shown in  FIG. 10 ; and 
         FIG. 12  is a pictorial bottom view of the radio signal substrate shown in  FIG. 10  showing partial adhesive layer. 
     
    
    
     DETAILED DESCRIPTION 
     Referring to  FIG. 1  there is shown a side perspective view of the portable RFID signal distortion device  10  according to this invention.  FIG. 1  illustrates an embodiment of the invention comprising layers of electric field distortion layer  16 , magnetic field distortion layer  14 , and print layer  10 . Optionally print layer  18  may also be included. 
     Referring still to  FIG. 1 , and also  FIG. 2 , the RFID blocking device  10  also comprises a media layer  12 . The media layer  12  may be any suitable media layer such as a flexible printable layer for conveying, for example, advertising instructions, warnings, or public service messages. The media layer  12  may also be a photographic layer comprising suitable photographic paper. 
     Referring also to  FIG. 1  and  FIG. 4 , the RFID blocking device  10  comprises electric field signal distortion layer  16 . The electric field distortion layer  16  may be any suitable electric field distortion layer having electric field distortion properties combined with flexible properties; such as, for example, aluminum foil. It will be appreciated that any suitable electric field distortion layer may be used, such as, for example: metalized fabrics, carbon impregnated polyethylene; mirrored plastics, metallic coated mesh; and conductive polyethylene and other plastics. 
     Referring also to  FIG. 1  and  FIG. 3 , the RFID blocking device  10  also includes a magnetically receptive layer  14  combined with flexible properties. Magnetically receptive layer  14  includes suitable substrate  31 . Substrate  31  may be any suitable substrate such as, for example, paper, foil, or fabric. Substrate  31  may be a separate substrate or alternatively may be one or both sides of media layer  12  and/or one or both sides of electric field signal distortion layer  16 . 
     Still referring to  FIG. 1  and  FIG. 3 , magnetically receptive layer  14  includes magnetically receptive signal distortion grating  36 . Magnetically receptive signal distortion grating  36  comprises magnetically receptive deposits  32  arranged to interfere with data transmission for impinging magnetic and electric fields generated by an RFID reader or by an RFID card activated by an RFID Reader. The magnetically receptive deposits  32  may be any suitable magnetically receptive deposit shape or character painted, printed, or otherwise deposited on magnetically receptive layer  14 . In addition, magnetically receptive signal distortion grating  36  also comprises spaces  38  between magnetically receptive deposits  32 . Spaces  38  may be any suitable size space between magnetically receptive deposits  32  selected to optimize interference. Magnetically receptive deposits  32  are preferably less than 25 microns thick. 
     The magnetically receptive layer  14  is generally imprinted upon substrate  31  and is generally on the order of a few microns in depth, however, any suitable receptive layer depth may be used. In addition, the magnetically receptive layer  14 , or a portion thereof, may be visible through the media layer  12 . The portion of the magnetically receptive layer  14  visible through the media layer  12  may display a mark or message after being exposed to a magnetic field. 
     Magnetic ink printing methods with inks containing magnetic particles are known. For example, U.S. Pat. No. 3,998,160 (incorporated herein in its entirety by reference) relates to various magnetic inks used in printing digits, characters, or designs on checks or bank notes. The magnetic ink used for these processes generally consists of acicular magnetic particles, such as magnetite in a fluid medium, and a magnetic coating of ferric oxide, chromium dioxide, or similar materials dispersed in a vehicle containing binders and plasticizers. 
     Single component toner compositions generally contain, for example, magnetic particles, such as magnetite, resin binders, and other additives. There are several types of magnetites ranging from soft to hard. Generally, there are three types of iron oxides used: (1) cubic; (2) octahedral; and (3) acicular. U.S. Pat. No. 4,859,550 (incorporated in its entirety by reference herein) indicates that hard and/or soft magnetites may be incorporated into toner at amounts of from 35-70% by weight. 
     In applications requiring magnetic ink character recognition (MICR) capabilities, toners must generally contain magnetites having specific properties, the most important of which is a high enough level of remanence or retentivity. Retentivity is a measure of the magnetism left when the magnetite is removed from the magnetic field, i.e., the residual magnetism. In applications requiring MICR capability, it is important for the toner to show a high enough retentivity such that when the characters are read, the magnetites produce a signal. This is the signal strength of the toner composition. The signal level can vary in proportion to the amount of toner deposited on the document being generated. It will be understood that the magnetically receptive layer  14  may be composed using MICR ink or toner. 
     In addition, toner compositions used in single component development applications, i.e., those having 40-50% soft magnetites, typically have a low retentivity and a low signal strength. Soft or cubic magnetites give a low retentivity whereas octahedral and acicular magnetites give a higher retentivity. Therefore, past toner compositions have contained high levels of acicular magnetites to provide the desired retentivity. However, the use of toner compositions with all acicular magnetites is expensive, and often exhibit signal strengths that are too high. Thus, it will be understood that the magnetically receptive layer  14  may be composed of any suitable shaped magnetite shape and composition. 
     Still referring to  FIG. 1  and  FIG. 3  spaces  38  between magnetically receptive deposits  32  may be arranged to augment, or not otherwise impede, a counter magnetic force generated by an eddy current within the electric field signal distortion layer  16 . 
     Referring now to  FIG. 6  there is shown a side perspective view of an alternate embodiment of the portable RFID signal distortion device shown in  FIG. 1 . RFID signal distortion device  60  includes print substrate  62 , adhesive layer  68 , and electric field interference substrate  66 . It will be understood that print substrate  62  and electric field interference substrate  66  are bonded together by adhesive layer  68  but are shown here as separate for illustration clarity and discussion. 
     Still referring to  FIG. 6 , print substrate  62  includes a printable or media surface  61  for printing artwork, general messages, instructions, or advertisement. Print substrate  62  also includes a magnetically receptive surface  63  for disrupting or interfering with data transmitted via RFID data transfer techniques such as magnetic induction or electric field backscatter techniques. 
       FIG. 6  also illustrates the adhesive layer  68 . The adhesive layer  68  may be any suitable adhesive suitable for bonding print substrate  62  and electric field interference substrate  66 . For example, adhesive layer  68  may be a pressure sensitive adhesive applied initially to either the print substrate  62  or electric field interference substrate  66  to facilitate manufacture of the portable RFID signal distortion device  60 . In addition, adhesive layer  68  may include magnetically receptive particles for disrupting or interfering with data transmitted via RFID data transfer techniques such as magnetic induction or electric field backscatter techniques. 
     Still referring to  FIG. 6  there is also shown a side view of electric field interference (EFI) substrate  66 . EFI substrate  66  includes EFI top surface  65  and EFI bottom surface  64 . EFI bottom surface  64  may also include a print receptive primer or color. EFI substrate  66  may be any suitable material or textile designed to interfere with data transmitted via RFID data transfer techniques such as magnetic induction or electric field backscatter techniques. In addition EFI substrate  66  may also be embossable with logos or messages showing EFI substrate  66  bottom surface  64 . 
     Referring also to  FIG. 7 , there is shown a pictorial top view of the print substrate  62  shown in  FIG. 6 . Print substrate  62  includes printable media surface  61  for printing artwork, general messages, instructions, or advertisement. 
     Referring also to  FIG. 8  there is shown is a pictorial bottom view of the print substrate  62  shown in  FIG. 6  showing magnetically receptive deposits  82  arranged with spaces  88  to form magnetically receptive signal distortion grating  86 . Magnetically receptive signal distortion grating  86  also comprises spaces  88  between magnetically receptive deposits  82 . Spaces  88  may be any suitable size or shape arranged between magnetically receptive deposits  82  to interfere with data transmission for impinging magnetic and electric fields generated by an RFID reader or by an RFID card activated by an RFID Reader. The magnetically receptive deposits  82  may be any suitable magnetically receptive deposit shape or character painted, printed, or otherwise deposited on print substrate  62 . 
     Referring also to  FIG. 9  there is shown a pictorial bottom view of the EFI substrate  66  shown in  FIG. 6  showing partial adhesive layer  91 . It will be understood that adhesive layer  91  covers the entire bottom area of the EFI substrate  66  and is partially shown here for illustration and description clarity. EFI substrate  66  may be any suitable material or textile designed to interfere with data transmitted via RFID data transfer techniques such as magnetic induction or electric field backscatter techniques. Further, EFI substrate  66  may be any suitable material or textile designed to operate in conjunction with signal distortion grating  86  to interfere with data transmission for impinging magnetic and electric fields generated by an RFID reader or by an RFID card activated by an RFID Reader when RFID signal distortion device  60  substrates are assembled. 
     Referring also to  FIG. 10  there is shown a side perspective view of an alternate embodiment of the portable RFID signal distortion device shown in  FIG. 1 . RFID signal distortion device  100  includes print substrate  102 , adhesive layer  108 , and electric field interference substrate  106 . It will be understood that print substrate  102  and electric field interference substrate  106  are bonded together by an adhesive layer  108  between substrate  102 , bottom surface  103 , and electric field interference substrate  106  top surface  105 ; but, the substrates are shown here as separate for illustration clarity and discussion. In addition, electric field interference substrate  106  also includes embossable surface  104  for embossing messages and, or, logos. 
     Still referring to  FIG. 10  and  FIG. 11 , print substrate  102  includes a printable or media surface  101  for printing artwork  101 D, general messages  101 B, instructions  101 C, or advertisement  101 E. Printed artwork  101 D, messages  101 B, instructions  101 C, and advertisement  101 E as shown in  FIG. 11  is optionally printed with magnetic ink to form a magnetically receptive surface  101 A for disrupting or interfering with data transmitted via RFID data transfer techniques such as magnetic induction or electric field backscatter techniques. The magnetically receptive surface  101 A is preferably less than 25 microns. 
     Referring also to  FIG. 12  there is shown a pictorial bottom view of the EFI substrate  106  shown in  FIG. 10  showing partial adhesive layer  121 . It will be understood that adhesive layer  121  covers the entire bottom area of the EFI substrate  106  and is partially shown here for illustration and description clarity. EFI substrate  106  may be any suitable material or textile designed to interfere with data transmitted via RFID data transfer techniques such as magnetic induction or electric field backscatter techniques. Further, EFI substrate  106  may be any suitable material or textile designed to operate in conjunction with magnetically receptive surface  101 A to interfere with data transmission for impinging magnetic and electric fields generated by an RFID reader or by an RFID card activated by an RFID Reader when RFID signal distortion device  100  substrates are assembled. 
     Referring also  FIG. 5  there is shown a pictorial view of a billfold  54  employing the invention shown in  FIG. 1 ,  FIG. 6  and  FIG. 10  adapted to the retrofitting of existing wallets, purses, credit card holders, and the like to provide protection by interfering with, or scrambling, data retrieval from RFID devices embedded in credit cards  52 , personal identification cards, and other cards contained and transported therein. The RFID signal distortion device  60  or portable RFID signal distortion device  10  is constructed to allow scalability to dimensions conforming to dimensions of user preferred conventional wallets, purses, credit card holders, and the like. 
     It will be understood that the present invention overcomes the prior art problems by disrupting, or scrambling, data transfer. Thus, the invention advantageously accomplishes the objectives of the prior art solutions, i.e., the prevention of electronic pick pocketing; but, without complex micro-circuitry or the cumbersome solutions to shield, or prevent the interrogation signal from reaching the RFID enabled device. 
     It should be understood that the foregoing description is only illustrative of the invention. Accordingly, the present invention is intended to embrace all such alternatives, modifications and variances which fall within the scope of the appended claims.