Anti-photocopying paper and/or anti-telefacsimile paper

摘要

Paper is provided with resistance to photocopying or transmission by telefacsimile by spatial spectral modulation of the paper reflectance at a specific single or preferably multiple frequencies. Such paper has a colored pattern of at least two colors repeating in at least one dimension of a face of a paper with at least one frequency in the range of from about 0.5 to about 50 times per cm. The colors contrast with black or similar dark color to permit black or similar dark colored information to be visible readable when applied to the colored pattern. The colors also cooperate with such information to provide a document resistant to photocopying and transmission by telefacsimile.