An identification document including a multilayer laminate having a core layer defining an opening therethrough, and a dynamic window in the opening. The dynamic window includes an optically variable coating on at least a front or a back of the dynamic window. The optically variable coating appears transparent when viewed from the front of the identification document in light transmitted through the dynamic window from the back of the identification document toward the front of the identification document, and appears nontransparent when viewed from the front of the identification document in light reflected from the front of the identification document. Fabricating an identification document with a dynamic window includes forming an opening in a core layer, positioning a dynamic window in the opening, and plate laminating the core layer and the dynamic window between at least one outer layer on each side of the core layer.

An identification document including a multilayer laminate having a core layer defining an opening therethrough, and a dynamic window in the opening. The dynamic window includes an optically variable coating on at least a front or a back of the dynamic window. The optically variable coating appears transparent when viewed from the front of the identification document in light transmitted through the dynamic window from the back of the identification document toward the front of the identification document, and appears nontransparent when viewed from the front of the identification document in light reflected from the front of the identification document. Fabricating an identification document with a dynamic window includes forming an opening in a core layer, positioning a dynamic window in the opening, and plate laminating the core layer and the dynamic window between at least one outer layer on each side of the core layer.

Paper substrates which incorporate covert marking pigments (CMPs) which are one or more infrared (IR) anti-Stokes pigments. Also, processes for incorporating such CMPs into a paper substrate other than by a printing technique, such as, for example, by using a size press or spraying, as well as processes for identifying the presence of such CMPs incorporated into a paper substrate sheet with an infrared (IR) pigment sensor of, for example, a copier or printer for the purpose of adjusting the quantity of printer pigment deposited on a paper substrate sheet or to determine whether the paper substrate sheet is an authentic or counterfeit document.

Paper substrates which incorporate covert marking pigments (CMPs) which are one or more infrared (IR) anti-Stokes pigments. Also, processes for incorporating such CMPs into a paper substrate other than by a printing technique, such as, for example, by using a size press or spraying, as well as processes for identifying the presence of such CMPs incorporated into a paper substrate sheet with an infrared (IR) pigment sensor of, for example, a copier or printer for the purpose of adjusting the quantity of printer pigment deposited on a paper substrate sheet or to determine whether the paper substrate sheet is an authentic or counterfeit document.

A security feature for protecting valuable documents, in particular for ensuring the authenticity of valuable documents, comprises a luminescent pigment which has a host lattice doped with a first luminophore and a second luminophore, with an excitation energy of the first luminophore being transferable to the second luminophore. However, in the case of the luminescent pigment according to the invention, the excitation energy is not transferred completely from the first luminophore to the second, but rather only partially. The incomplete transfer of the excitation energy is achieved by selecting suitable amount-of-substance fractions of the first and the second luminophores on the luminescent pigment. As a result of the incomplete transfer of the excitation energy, the luminescent light that is emitted by the luminescent pigment also has, in addition to a luminescence peak of the second luminophore, a luminescence peak of the first luminophore.

A security feature for protecting valuable documents, in particular for ensuring the authenticity of valuable documents, comprises a luminescent pigment which has a host lattice doped with a first luminophore and a second luminophore, with an excitation energy of the first luminophore being transferable to the second luminophore. However, in the case of the luminescent pigment according to the invention, the excitation energy is not transferred completely from the first luminophore to the second, but rather only partially. The incomplete transfer of the excitation energy is achieved by selecting suitable amount-of-substance fractions of the first and the second luminophores on the luminescent pigment. As a result of the incomplete transfer of the excitation energy, the luminescent light that is emitted by the luminescent pigment also has, in addition to a luminescence peak of the second luminophore, a luminescence peak of the first luminophore.

An anti-counterfeiting pattern having an optically variable structure, comprising lithographic lines and gravure blind embossed relief lines printed on a carrier. The lithographic lines are a set of lithographic curve lines having a curvature, the widths of the lithographic curve lines changing from thick to thin, or thin to thick. The gravure blind embossed relief lines are a set of curve lines corresponding to the lithographic lines, and having the same curvature. The relief lines are overprinted on the lithographic lines with a width variation identical to that of said lithographic lines. Accurate overprinting of the two printing types forms a curved relief structure wherein the width of the lines changes continuously. When a printed product is rotated and observed, a continuously variable optical effect will be seen, which is visual, readily to identify, anti-copying and difficult to forgery.

An anti-counterfeiting pattern having an optically variable structure, comprising lithographic lines and gravure blind embossed relief lines printed on a carrier. The lithographic lines are a set of lithographic curve lines having a curvature, the widths of the lithographic curve lines changing from thick to thin, or thin to thick. The gravure blind embossed relief lines are a set of curve lines corresponding to the lithographic lines, and having the same curvature. The relief lines are overprinted on the lithographic lines with a width variation identical to that of said lithographic lines. Accurate overprinting of the two printing types forms a curved relief structure wherein the width of the lines changes continuously. When a printed product is rotated and observed, a continuously variable optical effect will be seen, which is visual, readily to identify, anti-copying and difficult to forgery.

A near-infrared-absorption white material, a method of manufacturing the same, and uses thereof. The near-infrared-absorption material includes copper pyrophosphate compound. The copper pyrophosphate compound has a brightness (CIE L*) value of 90 or more in a visible-ray region and is excellent in particle manufacturing properties, and a crystalline structure of the copper pyrophosphate compound is made chemically stable using a heat treatment at a high temperature. The copper pyrophosphate compound is represented by the following chemical formula:
Cu.sub.2P.sub.2O.sub.7 or Cu.sub.2P.sub.2O.sub.7.XH.sub.2O (x=1-3).

A near-infrared-absorption white material, a method of manufacturing the same, and uses thereof. The near-infrared-absorption material includes copper pyrophosphate compound. The copper pyrophosphate compound has a brightness (CIE L*) value of 90 or more in a visible-ray region and is excellent in particle manufacturing properties, and a crystalline structure of the copper pyrophosphate compound is made chemically stable using a heat treatment at a high temperature. The copper pyrophosphate compound is represented by the following chemical formula:
Cu.sub.2P.sub.2O.sub.7 or Cu.sub.2P.sub.2O.sub.7.XH.sub.2O (x=1-3).