The invention relates to an absorbent medium for improving the overprintability, in particular by inkjet printing, of a security element, in particular an optically variable security element, comprising a binder, at least one pigment and an in particular aqueous solvent. The invention furthermore relates to a transfer film with an absorbent layer made of such an absorbent medium as well as a method for personalizing a security element using such a transfer film.

The invention relates to an absorbent medium for improving the overprintability, in particular by inkjet printing, of a security element, in particular an optically variable security element, comprising a binder, at least one pigment and an in particular aqueous solvent. The invention furthermore relates to a transfer film with an absorbent layer made of such an absorbent medium as well as a method for personalizing a security element using such a transfer film.

There is provided an optical structure having a quantization phase difference structure on one surface of a quantization phase difference structure layer, wherein in the quantization phase difference structure, a plurality of quantization projecting portions in a constant size and a plurality of quantization recessed portions in a constant size are aligned, wherein a multiple diffraction region has the quantization phase difference structure where ribbed projecting portions, in which the quantization projecting portions are aligned in one direction, are arranged adjacent to and alternately with groove-like recessed portions, in which the quantization recessed portions are aligned parallel to the ribbed projecting portions, and wherein the multiple diffraction region is a quantization phase difference structure configured to reproduce a plurality of reproduction points discrete in one direction and arranged regularly.

There is provided an optical structure having a quantization phase difference structure on one surface of a quantization phase difference structure layer, wherein in the quantization phase difference structure, a plurality of quantization projecting portions in a constant size and a plurality of quantization recessed portions in a constant size are aligned, wherein a multiple diffraction region has the quantization phase difference structure where ribbed projecting portions, in which the quantization projecting portions are aligned in one direction, are arranged adjacent to and alternately with groove-like recessed portions, in which the quantization recessed portions are aligned parallel to the ribbed projecting portions, and wherein the multiple diffraction region is a quantization phase difference structure configured to reproduce a plurality of reproduction points discrete in one direction and arranged regularly.

A decoration method of a printed matter includes: forming a printed layer on a surface of a sheet or of a mounting paper with a transparent varnish, printing a predetermined pattern on the surface of the printed layer by an ink or by a resin which are capable of being adhered to the printed layer; and pressing a metal foil onto the pattern printed by the ink or the resin with an adhesive agent. The adhesive agent does not adhere to the printed layer but adheres to the pattern. As a result, the metal foil 6 is printed only to the pattern.

An optical device includes an array of lenses and a plurality of first and second segments disposed under the array of lenses. At a first viewing angle, the array of lenses presents a first image for viewing without presenting the second image for viewing, and at a second viewing angle different from the first viewing angle, the array of lenses presents for viewing the second image without presenting the first image for viewing. In some examples, individual ones of the first and second segments can comprise specular reflecting, transparent, diffusely reflecting, and/or diffusely transmissive features. In some examples, individual ones of the first and second segments can comprise transparent and non-transparent regions. Some examples can incorporate more than one region producing an optical effect.

An optical device includes an array of lenses and a plurality of first and second segments disposed under the array of lenses. At a first viewing angle, the array of lenses presents a first image for viewing without presenting the second image for viewing, and at a second viewing angle different from the first viewing angle, the array of lenses presents for viewing the second image without presenting the first image for viewing. In some examples, individual ones of the first and second segments can comprise specular reflecting, transparent, diffusely reflecting, and/or diffusely transmissive features. In some examples, individual ones of the first and second segments can comprise transparent and non-transparent regions. Some examples can incorporate more than one region producing an optical effect.

The present invention relates to compositions, comprising silver nanoplatelets, wherein the mean diameter of the silver nanoplatelets, present in the composition, is in the range of 20 to 70 nm with standard deviation being less than 50% and the mean thickness of the silver nanoplatelets, present in the composition, is in the range of 5 to 30 nm with standard deviation being less than 50%, wherein the mean aspect ratio of the silver nanoplatelets is higher than 1.5, a process for its production, printing inks containing the compositions and their use in security products. The highest wavelength absorption maximum of the population of all silver nanoplatelets in the composition being within the range of 450 to 550 nm. A coating, comprising the composition, shows a red, or magenta color in transmission and a greenish-metallic color in reflection.

A document, product, or package, such as a banknote, passport or the like comprises structures having dichroic effects that change color with viewing angle in both transmission and reflection. Such structures can be useful as security features that counter the ability to effectively use counterfeit documents, products, packages, etc.

A document, product, or package, such as a banknote, passport or the like comprises structures having dichroic effects that change color with viewing angle in both transmission and reflection. Such structures can be useful as security features that counter the ability to effectively use counterfeit documents, products, packages, etc.