METHOD FOR MANUFACTURING A SECURITY PAPER AND A SUCTION DEVICE FOR PRODUCING THIN SITES OR OPENINGS IN A WET PAPER WEB AT PAPER MANUFACTURE

摘要

The invention relates to a method for manufacturing a security paper and a suction device for producing thin sites or openings in a wet paper web at paper manufacture. A method for manufacturing a security paper, characterized in that in a first wet end of a paper machine, a first paper web is formed and, if applicable, provided with individualization features, such as an opening or a watermark, in a second wet end of a paper machine, a second paper web is formed, the second paper web is merged and firmly joined with the first paper web via a pickup belt, and that from the second paper web, still in the wet state, paper fibers are removed by means of a suction apparatus, preferably in register with any existing individualization features of the first paper web. The suction apparatus is formed by a suction wheel, composed of multiple segment plates, in which are provided at least one intermediate plate forming the extraction openings, and two cover plates forming edge delimiters.