Abstract: An identification medium can be used in an opening label, clearly show signs of it having been opened, and also have a superior authenticity-confirming function. The identification medium has a structure including, in the following order as seen from the side of observation: an optical function layer that generates a color shift, a separation layer that is partially formed, a printed layer, and an adhesive layer, in which when an adhesive strength between the adhesive layer and an adherend is set to be Xa, an adhesive strength between the adhesive layer and the printed layer is set to be Xb, and an adhesive strength at a portion in which the separation layer is laminated between the optical function layer and the printed layer is set to be Xc, the adhesive strength of each part is set to satisfy Xa>Xb>Xc or Xb>Xa>Xc.

Abstract: In an identification medium, switching of images can be clearly observed, and the medium has a structure produced at low cost. The structure comprises a cholesteric liquid crystal layer 102 in which a hologram is formed, and which selectively reflects circularly polarized light of a specific rotating direction of a specific central wavelength, a cholesteric liquid crystal layer reflecting the entire range of visible light 105 which has reflection characteristics equivalent to a case of reflecting the entire range of visible light and which reflects circularly polarized light of the same rotating direction as the circularly polarized light reflected from the cholesteric liquid crystal layer 102, and a display pattern 106 having a specific content displayed, arranged in this order, as seen from the side of observation.

Abstract: An identification medium can be used in an opening label, clearly show signs of it having been opened, and also have a superior authenticity-confirming function. The identification medium has a structure including, in the following order as seen from the side of observation: an optical function layer that generates a color shift, a separation layer that is partially formed, a printed layer, and an adhesive layer, in which when an adhesive strength between the adhesive layer and an adherend is set to be Xa, an adhesive strength between the adhesive layer and the printed layer is set to be Xb, and an adhesive strength at a portion in which the separation layer is laminated between the optical function layer and the printed layer is set to be Xc, the adhesive strength of each part is set to satisfy Xa>Xb>Xc or Xb>Xa>Xc.

Abstract: An identification medium cannot be reused when an attempt has been made to remove it from an object by using solvent. A cholesteric liquid crystal layer subjected to a hologram processing is formed while contacting a COP (cycloolefin polymer) layer. When the identification medium is removed using a solvent from a state in which it was adhered to an object by an adhesive layer, the COP layer is melted by the solvent and is damaged. The COP layer is a layer which functions as a substrate of the identification medium, and the identification medium is damaged by contacting with the solvent, as described above, and it is difficult to reuse.

Abstract: In an identification medium, switching of images can be clearly observed, and the medium has a structure produced at low cost. The structure comprises a cholesteric liquid crystal layer 102 in which a hologram is formed, and which selectively reflects circularly polarized light of a specific rotating direction of a specific central wavelength, a cholesteric liquid crystal layer reflecting the entire range of visible light 105 which has reflection characteristics equivalent to a case of reflecting the entire range of visible light and which reflects circularly polarized light of the same rotating direction as the circularly polarized light reflected from the cholesteric liquid crystal layer 102, and a display pattern 106 having a specific content displayed, arranged in this order, as seen from the side of observation.