Technique for producing window-open type broad safety line money paper by single-circle mesh paper machine

Abstract

The invention relates to a technology of the single-round net paper machine to produce the fenestration-type wide safety line Bank Paper. It contains the following steps: distribute paper pulp on the round net part of the single-round net paper machine to form paper sheets. During the forming process, release the wide safety line clinging to the fenestration plate (2) of the round net part by the releasing frame (5). The paper sheets are sent from the round net part to the press part for dewatering. The press part adopts the vacuum composite pressing with three rolls and two pressure areas. The water can discharge quickly through the blanket oillets under the vacuum aspiration. Then, the paper sheets enter the dryer part to pass two groups of ten dryers for drying. After drying, the paper sheets enter the sizing part for sizing and the back dryer part for finishing. Finally, the paper sheets can achieve the better smoothness through the soft calendar and roll to the paper axis with the regulation size. The invention produces the fenestration-type wide safety line Bank Paper successfully by using the single-round net paper machine.

Description

technical field [0001] The invention relates to a process for producing banknote paper with a window-type wide security line, which can produce window-type banknote paper with a wide security line meeting the anti-counterfeiting and technical requirements on a single cylinder paper machine. Background technique [0002] At present, the application of window-type wide security thread in the production of banknote paper as a popular anti-counterfeiting technology has attracted more and more attention from all over the world. The wider the security thread is, the more difficult it is to produce and the higher the anti-counterfeiting performance is. . [0003] In the prior art, someone has used a single cylinder wire machine to produce window-type narrow security line (for example, 1.5 mm) banknote paper, yet the applicant has not heard of anyone using a single cylinder wire machine to produce window paper Type wide security thread banknote paper, wide security thread generally...

AI Technical Summary

Problems solved by technology

This is because the paper produced by the single cylinder paper machine is a single-layer cloth pulp, 80-90g / m 2 The slurry is formed in the cylinder wire section of the single cylinder wire paper machine at one time. The thickness of the paper sheet is only about 100 microns, while the thickness of the window-type safety thread reaches about 35 microns. During the slurry forming process, the safety thread is The upper and lower positions in the pulp layer are not easy to control, so in the production of window-opening security thread banknote paper, it is easy to have defects where the window should be opened on the surface of the security thread buried in the pulp or defects where the thread should be buried ( Such as: the part where the thread should be fully embedded on the reverse side of the window is very prone to the defect of exposed line), especially in the production of banknote paper with a wide security line (such as a 3.0mm wide security line) where the security line is likely to occur Rafting and longitudinal crushing of paper sheets at the safety line cause paper defects such as large areas of exposed lines on the paper sheet, which directly affect product quality and continuous production

Therefore, before the technology of the present invention appeared, it was not possible to produce window-type wide security line banknote paper on a single cylinder paper machine, but to produce window paper by a multi-cylinder paper machine (or the cooperation of a cylinder and a short former). However, the structure of the multi-drum paper machine (or the combination of the drum and the short former) is complicated, and because the other drum or the short former of the multi-drum paper machine generally adopts spraying When the pulp is sprayed on the Internet, it is easy to cause small pulp rolls due to the mismatch between the pulp speed and the net speed during the spraying process, and the pulp will form small pulp rolls, which are manifested as pulp rolls (rolled pulp clusters) defects on the paper. It will affect product quality and yield to a certain extent

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