Anti-counterfeit watermark paper

One of the major trends is the change from long webs of paper to high-security circular webs.

There are three reasons for this:
· Obtain better and safer watermarks · Gain additional security measures (such as security lines, etc.) that are not available on the long web of paper
· Add long cotton fibers to wood pulp to increase paper life

A better watermark means:
1. There are more levels of circular web watermarks available for up to 15 gray levels.
2. Better Contrast In circular screen paper, the thickness of the black watermark area can reach 40μ, which is much thicker than the paper itself with an average thickness of 15-20μ. The thickness of the long paper is not significantly different.
3, better details or watermark clarity

It is for the above three reasons that the circular watermark watermark paper is more difficult to counterfeit than the long watermark watermark paper. The difference in the quality of watermarks for rotary screens and long screens is due to differences in the manufacturing process. In a rotary screen machine, the watermark is formed by the accumulation of fibers on the watermark surface, and the watermark is formed simultaneously with the paper. This means that the watermark can be filled into the peaks and valleys of the circular model, resulting in a very clear watermark.

On the Fourdrinier paper machine, paper is formed one by one. When the paper is still wet, the watermark is formed by pressing the engraved steel roller against the wet paper surface. Circular nets, as the name implies, refer to the molding process, and the long web can be described as a pressing process.

The speed of the two processes has an impact on the quality of the watermark. The long wire machine runs faster than the rotary screen machine, and there is almost no time for the paper fibers to enter the depth of the gravure roll. Most of the paper, including writing paper, newsprint paper, and business letter paper, are produced on a Fourdrinier paper machine.