FIELD: image forming devices; manufacturing technology.
SUBSTANCE: hidden image in the thin sheet material body creation method from plurality of the volumetric nano-structures pairs for the securities and identification documents protection against forgery by several common characters. Method is implemented by acting on given points of the sheet material from the metal layer surface between two layers of plastic, located on the micro-lenses layer in the form of glass microbeads, deposited on the plastic substrate and partially immersed in the luminophor layer by the above-threshold power laser pulses. As a result, in the sheet material within the laser spot tremendous pressure occurs, displacing composing the laser beam light waves to the laser spot periphery. These waves penetrate inside the sheet material, within the laser spot fuse the micro-lenses with metal and luminophor particles, penetrate the plastic substrate, forming channels in it, and under the influence of enormous return pressure from micro-lenses reaching 100,000 atm., and high temperatures of the order of 3,000–4,000 °C in the adjacent to the metal layer plastic form between them the latent image points from the volumetric nanostructures pairs and nano-whiskers rows. In fact, the volumetric nanostructures pairs and nano-whiskers rows are formed as the result of the metal, glass, luminophor and plastic alloy high-speed crystallization. As a result of crystallization, on the sheet material front surface an image is formed from the points, which are a collection of crystals, and located between them the nano-whiskers rows represent the diffraction grids equivalent. With the sheet material turning relative to the light source, on the nano-whiskers rows its dispersion occurs, as a result of which, the subjected dispersion white light paints the crystal in different colors, creating a color iridescent image on the sheet material front surface. Proposed method enables creation of two more common characters to protect this material against counterfeiting, on the sheet material back side ensuring formation of the black and white image from the channels in the plastic substrate and visible in transmitted light the original color image inside the sheet material.
EFFECT: proposed security features are created by the proposed method in a thin film, so that this method can protect both securities and identification documents against forgery.
6 cl, 4 dwg
