Water-based coating is an effective means to process the surface of printed matter, to improve the gloss and strength of the surface of printed matter, enhance the aesthetic effect, temperature resistance, water resistance, wear resistance, improve the grade of printed matter and commodity value. Therefore, to measure the quality of the coating, it is also necessary to examine the brightness, strength, adhesion and other aspects of the coating.

Water-based coating is an effective means to process figures on the surface of printed matter, to improve the gloss and strength of printed matter surface, enhance the aesthetic effect, temperature resistance, water resistance, wear resistance, improve the grade of printed matter and commodity value, so to measure the quality of the film Fuji Star, also need to examine the brightness, strength, adhesion and other aspects of the film.

The development of water-based laminating machine makes the water-based laminating process widely promoted and applied. Water-based wet laminating is favored by the majority of customers for its high strength, high grade, easy recovery, no pollution and other characteristics of laminating printed matter.

Water-based film coating process has just been promoted, because customers do not know much about this process, more concerns about film, afraid of problems, in view of this, had done a lot of tests for customers in advance, such as:  in order to test the combined printing of water-coated printed matter with temperature resistance, humidity resistance and oil resistance, has done the relevant film coating test in the early use of the machine, whether temperature resistance, humidity resistance and oil resistance, can meet the requirements of the film coating products.

Laminating process is more complex, in normal production still need to pay attention to the following problems:Powder printing

Print product dusting

Because water-based glue can dissolve powder on the surface of printed matter, so when the coated product snowflake point when the post-press process, it will feel incomprehensible, in fact, the reason is very simple, water-based glue itself is also limited by solubility, if the printing powder is too large, the excess part can not be completely dissolved by glue plate making, there will be a large area of snow.

There are three ways to deal with this situation:

1. Coordinate the upper and lower processes to minimize the amount of powder spraying during printing

2. The amount of glue water should be increased appropriately to increase the ability of the glue to dissolve the powder; Digital printing post-press processing

3. Clean the surface of the printed matter with suspended powder spraying before coating

Clean

Due to the water-based coating adhesive drying quickly, if static no flow, will dry into rubber equipment maintenance and maintenance, into a solid block. If attached to the rubber roll or pressure roll, it will cause local glue is too small, or pressure when the local pressure is too large. So in the coating process to keep the rubber roll and pressure roll clean.

If there is too much dust in the surrounding environment into glue dry rubber and cut film fragments, coated products will have snow, so we should pay attention to environmental hygiene, glue should not be finished back to the glue bucket sealed redundancy, or take the method of filtering before glue.

If there is too much dust in the surrounding environment into glue dry rubber and cut film fragments, coated products will have snow, so we should pay attention to environmental hygiene, glue should not be finished back to the glue bucket sealed redundancy, or take the method of filtering before glue.

Discoloration

It mainly appears in large - area gold printing and bronzing products. This is due to a chemical reaction between chemically active elements in the glue and the gold powder.

The solution is: for gold printing products using special gold ink or special glue, or change the process, bronzing products first coated after bronzing, many manufacturers use the latter process, the effect is very good.

Paper and plastic detachment

This phenomenon is easy to appear in the prepress process in the full print, because the surface ink layer is thick, the glue is difficult to wet, diffusion, penetration, and the bonding is not strong.

The solution is:

1. For this product, glue manufacturers are required to increase the solid content of adhesive;

2. Increase the thickness of the coating layer appropriately;

3. Increase the external temperature during the coating and product drying process;

4. Check whether the glue deteriorates, check the factory date and shelf life of the adhesive;

5. Whether the film is packaged and printed beyond the warranty period, check whether the corona treatment of the film is invalid.

Transformation

There are the following reasons for this situation:

1. The amount of glue is too large, because the amount of glue water will inevitably make the paper absorb water.Any paper will deform when it absorbs a lot of water. So in the absence of snowflake point, try to reduce the amount of glue;

2. Laminating tensile deformation is serious, at this time should be appropriate to adjust the film tension testing system and instrument, as long as the film can be smooth and paper fit, the smaller the tension force is the better;

3. The winding tension is too large. Under the premise of ensuring that the product can be rewound to the roll after the review, the smaller the tightening force, the better;

4. The temperature difference and humidity difference of the external environment of the film are too large.

At present, there is also a kind of glue between oil and water, the price is very cheap, itself without drying variable data printing, natural drying after the film, the brightness and smoothness of the covered products can meet the requirements, but it has a strong irritating smell, the quality is not stable. Can be used for low grade products. High-grade products are recommended to use the formal manufacturer of white environmental protection glue. With the rapid development of printing and packaging industry, waterborne film will have a broader prospect.

At present, our company's waterborne glue and water based adhesive and waterborne resin, has been put on the market, the market feedback is good, the performance is excellent, fully able to meet the complex needs of customers of various packaging structures.