| 摘要 |
FIELD: printing.SUBSTANCE: invention relates to a valuable document that is protected against forgery. The valuable document comprises coating in the form of a printing raster, made with at least one colour that is different from the colour of the basis of the document. Also, the document comprises a three-dimensional raster located in relation to the coating so that the three-dimensional screen is at least partially located on the coating, is mainly oriented parallel to the lines of the printing raster, and with the coating it forms a latent image which is indistinguishable when observing the document at right angle to the surface. At least some of the three-dimensional raster strokes are made with asymmetrical cross section profile with the ratio of the profile walls of not less than 1:1.25; thereby when changing the angle of observation the latent image is appeared which is made in the form of coloured elements or monochromatic coloured field. When changing the direction of viewing the document by 180° at the same angle of observation an effect of the change in optical density or colour-grade of at least a part of the latent image appears.EFFECT: invention enables to improve protection against forgery of valuable document with an optically variable image, which makes it possible to carry out a visual control of authenticity by the unskilled user, both with and without the use of simple and accessible technical devices to determine the authenticity of the document.29 cl, 11 dwg, 4 ex |
