An object of the present invention is to provide a thin volume hologram sheet to be embedded sufficiently resistant to a mechanical stress such as a stress including a tensile stress, a shear stress and a compression stress at the time of processing even under a heating condition, a forgery prevention paper and a card using the same. The object is achieved by providing a volume hologram sheet to be embedded comprising a volume hologram layer, and a substrate disposed only on one side surface of the volume hologram layer using an adhesion means, wherein a peeling strength of the volume hologram layer and the substrate is 25 gf/25 mm or more.

A method for marking an item including a shape memory polymer (SMP) having a visual readable and/or machine readable graphic element on the surface of the item. The method includes pretreating the surface of the item; coloring the surface of the item with a dye solution containing an organic dye and an organic solvent; cleaning and drying the surface of the item; and engraving by at least partially ablating the surface of the item. The dyeing process is suitable for coloring the surface of a shape memory polymer (SMP), wherein the information is engraved in a form of a code or other label on the colored surface. The coloring causes an increased contrast and thus facilitates machine readability of marking and coding without affecting the other properties of the SMP.

The present invention relates to a security document and/or document of value with a hologram in a visually changeable window as a novel security element, and also to a method for producing the same.

The invention relates to a security element for a security and/or valuable document, comprising a matrix based on an organic polymeric material and at least one electrically conductive pigment dispersed in the matrix and at least one organic luminescent substance dispersed in the matrix. In the presence of the conductive pigment the luminescent substance is capable of non-contact excitation of light emission where the particle size is less than 200 nm. The luminescent substance is not encapsulated and is directly surrounded by the matrix and is embedded therein. The invention also relates to uses of the security and/or valuable document and to the security and/or valuable documents produced by such uses.

The invention relates to polycarbonate-based or copolycarbonate-based security documents and/or documents of value which contain at least one hologram integrated in the card body, and to a method for producing such security documents and/or documents of value.