With the rapid development of the fifth generation wireless network and technology, touch screen mobile phone, tablet computer, LIQUID crystal display and other internal materials continue to produce grade, all aspects of materials, parts of the rapid update, applied in these products of various types of protective film, optical film, functional film, New energy films require thinner, more uniform, but also need to have high transparency, low fog, excellent contact and smoothness.
The quality of functional adhesives and coatings is the basic condition that determines these properties. In the process of precision coating, the filtration of adhesive is more and more demanding. At present, deep filter element combined with folded filter element is adopted for glue supply filtration of coater. Then, due to different types of filter elements,Different filtration mechanisms and different applications often occur during filtration fiber shedding and filtration unclean phenomenon.
Combined with the actual feedback problems of coating companies, several appropriate filtration technologies and solutions are briefly analyzed to help enterprises solve the problem of adhesive filtration and improve product quality.

1. Fiber shedding
In the filtration of high viscosity liquid, due to the friction force of liquid flow will gradually destroy the structure between the fibers, so that the fibers break off, resulting in the appearance of fibrous substance in the glue. Fibrous material is mainly due to the loss of the main fiber of the low-end filter element matched by the manufacturer.
Lentop adopts advanced hot melt welding technology and imported raw materials made of filter elements after ultra-pure water washing, drying and other environment greatly reduces the probability of fiber shedding.

2. Gel penetration
Gel penetration is one of the common problems in adhesive filtration, which directly leads to black spots and dark lines in film products. The main reason is that the selection of filter element and the design of filter solutions do not match. Adhesives generally contain not less than 30% solid content, and most of the glue is unfiltered, or only use ordinary filter or filter cloth for simple filtration, so the adhesive in the dilution will produce more colloids particles. In this case, Lentop recommends using a deep filter element with polypropylene as the filter material first. It is suitable for pre-filtration of adhesives with high gel content and low viscosity. It can improve filtration stability and reduce gel penetration.
After deep filtration, most of the colloidal particles are removed, but it is still possible for very fine gel particles to flow downstream through the filtration layer.These fine gels are smaller than those found in ordinary filtration media. They are not easy to be isolated by filtration, and colloidal particles have certain adhesion. Therefore, for the residual fine gel particles, deep filtration materials with adsorption performance can be selected, such as nanometer fiber filter membrane material.The filter element made by folding process has a filtration efficiency of 99.9%, which can remove fine gel impurities.