What are the development of coater in these years?The coating production of pet optical film coater mainly uses the optical film coater, which is used to coat materials with special functional glue, coating or ink, dry and roll up after rolling. The special high-speed cloth applicator can effectively reduce the generation of bubbles. The retractable roll coater is arranged with full-automatic splicing mechanism. The optical film coater with closed-loop automatic control of film tension needs to uniformly bond the aluminum foil or ink adhesion materials, plastic film, cloth or fabric surface, and the coating process requirements are relatively high, not only highly uniform Coating, but also to make high-speed roll replacement without downtime, improve production efficiency.
The optical thin film is composed of a thin layer of medium, which transmits light through the interface. The application of pet optical film coater began in 1930s. Modern optical film has been widely used in the field of Optics and optoelectronics, and various optical instruments have been manufactured. The characteristics of optical thin films are: smooth surface, geometric segmentation of the interface between the layers; the refractive index of the thin films can jump on the interface, but it is continuous in the film layer; it can be transparent medium or light absorbing medium; it can be normal and uniform or normal and uneven.
In the traditional paper machine, when the speed of the paper machine is over 1000m / min, there will be turbulence in the material pool, which will cause the spray of the rubber. It needs to increase the pressure of the press area to maintain the same amount of rubber, but this will increase the tendency of paper breaking. The door roller sizing technology developed in the 1960s significantly increased the potential for speed-up. However, due to the spray at the outlet of the roller pressure zone or the splash of the tank, the speed limit is about 1200 ~ 1300m/min.
In order to solve the problem of door roller sizing and pressing, the coater manufacturer developed film press with short dwell metering applicator head. In the future, this kind of effective film sizing press is applied to film coating, which is called film press coating. The results show that the film press can be used for surface sizing or precoating with the application amount of 0.7-4.0g/m2 (coating solid content of 5% - 18%) on each side, or for pigment coating with the application amount of 3-15g / m2 (coating solid content of 30% - 60%) on each side. At present, film press coating has been widely used in coated paper with and without mechanical wood pulp, as well as some special coated paper.
Coating machine film coating plus on-line soft calendering, has been able to produce low-cost high-quality LWC paper. LWC paper for gravure coater has reached a satisfactory smoothness index in the pilot scale film press coating. Another use is LWC base paper surface sizing and double coated paper precoating.
In the past 10 years, the film coating press has been installed in a new type of paper machine that does not contain mechanical wood pulp paper. The introduction of a large diameter smooth metering rod in the film press coating can be used for online precoating without mechanical wood pulp paper. This kind of paper used to be finished by the combination of surface sizing and external scraper pre coating. Film press has been identified as a low volume, non surface sizing, non mechanical wood pulp double coating machine. It has been successfully coated on a single layer of wood pulp free paper with a speed of less than 1200m / min and a coating capacity of 2-15g / m2 per surface.