Abstract: Security documents often incorporate optically variable devices to prevent or hinder counterfeiters. Disclosed herein are layered optically variable devices such as color-shift foils, and methods for their production and use. Such devices afford new techniques for a user of a security document to check quickly and easily whether the security document is a legitimate document or a counterfeit copy.

Abstract: Security documents often incorporate optically variable devices to prevent or hinder counterfeiters. Disclosed herein are layered optically variable devices such as colour-shift foils, and methods for their production and use. Such devices afford new techniques for a user of a security document to check quickly and easily whether the security document is a legitimate document or a counterfeit copy.

Abstract: A self-verifying security document, such as a banknote, comprises a flexible sheet formed from a plastics substrate bearing indicia. The sheet has a window of transparent plastics material that includes self-verification means for verifying a security device provided at a laterally spaced second portion of the sheet when the sheet is bent or folded to bring the window into register with the security device. The self-verification means may be an optical lens for reading an area of microprinting. In another embodiment, the self-verification means may be an optical filter for viewing an area printed with metameric inks. In other embodiments, the self-verification means and the security device may be polarizing windows or Moire inducing patterns.

Abstract: A method of determining at least one characteristic of one or more security documents such as banknotes, each security document including a sheet-like substrate of plastics material and opacifying layers applied to opposing faces of the substrate, the method comprising the steps of:(a) projecting radiation from a radiation source into the substrate of each security document for propagation therein, the opacifying layers acting to guide the projecting radiation within the substrate; (b) detecting a radiation emission of the substrate of each security document, the radiation emission resulting from the propagated radiation; and (c) analysing one or more characteristics of the radiation emission.

Abstract: A self-verifying security document, such as a banknote (1) comprises a flexible sheet formed from a plastics substrate (2) bearing indicia (3). The sheet has a window (5) of transparent plastics material which includes self-verification means (11) for verifying a security device (4) provided at a laterally spaced second portion of the sheet when the sheet is bent or folded to bring the window (5) into register with the security device (4). The self-verification means may be an optical lens (11) for reading an area of microprinting (10). In another embodiment, the self-verification means may be an optical filter (21) for viewing an area (22) printed with metameric inks. In other embodiments, the self-verification means and the security device (4) may be polarising windows (31, 32) or Moire inducing patterns (41, 42).

Abstract: A self-verifying security document, such as a banknote, comprises a flexible sheet formed from a plastics substrate bearing indicia. The sheet has a window of transparent plastics material which includes self-verification means for verifying a security device provided at a laterally spaced second portion of the sheet when the sheet is bent or folded to bring the window into register with the security device. The self-verification means may be an optical lens for reading an area of microprinting. In another embodiment, the self-verification means may be an optical filter for viewing an area printed with metameric inks. In other embodiments, the self-verification means and the security device may be polarizing windows or Moire inducing patterns.

Abstract: A self-verifying security document, such as a banknote (1) comprises a flexible sheet formed from a plastics substrate (2) bearing indicia (3). The sheet has a window (5) of transparent plastics material which includes self-verification means (11) for verifying a security device (4) provided at a laterally spaced second portion of the sheet when the sheet is bent or folded to brings the window (5) into register with the security device (4). The self-verification means may be an optical lens (11) for reading an area of microprinting (10). In another embodiment, the self-verification means may be an optical filter (21) for viewing an area (22) printed with metameric inks. In other embodiments, the self-verification means and the security device (4) may be polarising windows (31, 32) or Moire inducing patterns (41, 42).

Abstract: A self-verifying security document, such as a banknote (1) comprises a flexible sheet formed from a plastics substrate (2) bearing indicia (3). The sheet has a window (5) of transparent plastics material which includes self-verification means (11) for verifying a security device (4) provided at a laterally spaced second portion of the sheet when the sheet is bent or folded to bring the window (5) into register with the security device (4). The self-verification means may be an optical lens (11) for reading an area of microprinting (10). In another embodiment, the self-verification means may be an optical filter (21) for viewing an area (22) printed with metameric inks. In other embodiments, the self-verification means and the security device (4) may be polarising windows (31, 32) or Moire inducing patterns (41, 42).

Abstract: A method of determining at least one characteristic of one or more security documents such as banknotes, each security document including a sheet-like substrate of plastics material and opacifying layers applied to opposing faces of the substrate, the method comprising the steps of: (a) projecting radiation from a radiation source into the substrate of each security document for propagation therein, the opacifying layers acting to guide the projecting radiation within the substrate; (b) detecting a radiation emission of the substrate of each security document, the radiation emission resulting from the propagated radiation; and (c) analysing one or more characteristics of the radiation emission.

Abstract: A self-verifying security document, such as a banknote (1) comprises a flexible sheet formed from a plastics substrate (2) bearing indicia (3). The sheet has a window (5) of transparent plastics material which includes self-verification means (11) for verifying a security device (4) provided at a laterally spaced second portion of the sheet when the sheet is bent or folded to bring the window (5) into register with the security device (4). The self-verification means may be an optical lens (11) for reading an area of microprinting (10). In another embodiment, the self-verification means may be an optical filter (21) for viewing an area (22) printed with metameric inks. In other embodiments, the self-verification means and the security device (4) may be polarizing windows (31, 32) or Moire inducing patterns (41, 42).

Abstract: A self-verifying security document, such as a banknote, comprises a flexible sheet formed from a plastics substrate bearing indicia. The sheet has a window of transparent plastics material which includes self-verification means for verifying a security device provided at a laterally spaced second portion of the sheet when the sheet is bent or folded to bring the window into register with the security device. The self-verification means may be an optical lens for reading an area of microprinting. In another embodiment, the self-verification means may be an optical filter for viewing an area printed with metameric inks. In other embodiments, the self-verification means and the security device may be polarizing windows or Moire inducing patterns.

Abstract: One aspect of the present invention provides a method of producing a security document, including the steps of: (a) forming a sheet-like substrate of plastics material having first and second opposing surfaces, (b) coating a first layer of polymer material containing magnetic particles on the first opposing surface, (c) melting at least a portion of the first layer such that the magnetic particles can orient under the influence of a magnetic field, (d) applying the magnetic field so as to form a magnetic watermark, and (e) allowing the first layer portion to cool so as to fix the orientation of the magnetic particles

Abstract: A self-verifying security document, such as a banknote (1) comprises a flexible sheet formed from a plastics substrate (2) bearing indicia (3). The sheet has a window (5) of transparent plastics material which includes self-verification means (11) for verifying a security device (4) provided at a laterally spaced second portion of the sheet when the sheet is bent or folded to bring the window (5) into register with the security device (4). The self-verification means may be an optical lens (11) for reading an area of microprinting (10). In another embodiment, the self-verification means may be an optical filter (21) for viewing an area (22) printed with metameric inks. In other embodiments, the self-verification means and the security device (4) may be polarizing windows (31, 32) or Moire inducing patterns (41, 42).

Abstract: A self-verifying security document, such as a banknote (1) comprises a flexible sheet formed from a plastics substrate (2) bearing indicia (3). The sheet bas a window (5) of transparent plastics material which includes self-verification means (11) for verifying a security device (4) provided at a laterally spaced second portion of the sheet when the sheet is bent or folded to bring the window (5) into register with the security device (4). The self-verification means may be an optical lens (11) for reading an area of microprinting (10). In another embodiment, the self-verification means may be an optical filter (21) for viewing an area (22) printed with metameric inks. In other embodiments, the self-verification means and the security device (4) may be polarising windows (31, 32) or Moire inducing patterns (41, 42).

Abstract: A self-verifying security document, such as a banknote (1) comprises a flexible sheet formed from a plastics substrate (2) bearing indicia (3). The sheet has a window (5) of transparent plastics material which includes self-verification means (11) for verifying a security device (4) provided at a laterally spaced second portion of the sheet when the sheet is bent or folded to bring the window (5) into register with the security device (4). The self-verification means may be an optical lens (11) for reading an area of microprinting (10). In another embodiment, the self-verification means may be an optical filter (21) for viewing an area (22) printed with metameric inks. In other embodiments, the self-verification means and the security device (4) may be polarising windows (31, 32) or Moire inducing patterns (41, 42).