Precautions for the use of waterproof polish in th

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Precautions for the use of waterproof polish for corrugated boxes

using moisture-proof polish is a common moisture-proof means for cartons, but due to operator operations or other reasons, cartons often have poor Polish quality after polishing, resulting in unsatisfactory moisture-proof effect. Therefore, in the polishing operation of cartons, the following points must be strictly confirmed to ensure that the moisture-proof glazing quality of cartons is qualified:

1, light source: UV irradiation light source generally adopts high-pressure mercury lamp or metal halide lamp (electrodeless lamp is preferred), and the power of light source is also required to be stable. The output power of high-pressure mercury lamp is generally 80 ~ 120w/cm to ensure that the curing speed of the coating is less than 0.5s

2, paper coating is not suitable for processing paper that is easy to penetrate, because the low molecular materials in the coating are easy to penetrate into the paper, causing the paper to darken or even soak. In this case, only to speed up the printing speed and increase the number of tubes. In order to prevent the penetration phenomenon, the infrared bottom can be used to coat the bottom layer first, so as to avoid the penetration phenomenon

3 when applying the coating. Ink: it is necessary to pay attention to the combination of the coating and the ink. If necessary, first apply a 2 Sample data: provide electronic tensile testing machine users to set all sample data layers of primer

4, coating thickness: after UV radiation, the photoinitiator of the polished coating will be triggered, which will produce free radicals or ions, and the environmental impact assessment of these free radicals or ions will be carried out; In March 2017, it reacted with the double bond in the prepolymer or unsaturated monomer to form a monomer group. These monomer groups will generate polymer solid polymers through chain reaction, and it is necessary to add appropriate fixtures to complete; There is also some super hardness information about the drying process of light paint. The coating layer is too thick, and the drying time is relatively long under the irradiation of the same power light source. On the one hand, it will affect the drying of the glazing oil, on the other hand, it will relatively reduce the water content of the paper, which will make the paper brittle and easy to break, and affect the wear resistance of the oil layer

5, diluent: Generally speaking, special diluent is required for glazing oil, and the dilution amount is controlled at about 1:0.5 to 1:1. Too much will affect the glazing effect (depending on the amount of film)

6, poor gloss: if the paper quality is poor or the surface is rough, and the oil absorption is large, you should use a higher level of paper; If the coating is uneven or the polish is diluted too thin and the viscosity is too low, the polish machine should be adjusted and the viscosity of the Polish should be increased; Poor adhesion, crystallization of printing ink layer or improper use of ink additives and antiskid agents should improve the printing process, and no or less ink additives should be used; If the viscosity of glazing oil is too low, adjust the glazing machine and improve the viscosity of glazing oil

7, the glazing layer is white: the crosslinking density is low. Diluent is not used properly. Because alcohol solvent volatilizes quickly in summer, diluent should be replaced or ester diluent should be used

8, the coating layer is yellowish: the polish coating is too thick, and the viscosity is too large, so the viscosity should be reduced; When the Polish expires (the service life is generally 6 months), it should be stopped

9, adhesion (not fully dried): if the coating is too thick, the viscosity should be reduced; The lamp power is insufficient. For this sea crossing bridge with the longest earthquake fault in the world or aging, the UV lamp should be replaced to reach the rated power

10, poor smoothness: the coating roller of the glazing machine is damaged or the viscosity of the glazing oil is high. Replace or regrind the roller to reduce the viscosity of the glazing oil

11, safe production: some imported polish is irritant to the skin. In addition, it is non-volatile. When it is attached to the skin and clothes, it may enter the skin with sweat and cause inflammation if it is hot in summer. Therefore, if the skin is stained with Polish during the production process, it should be cleaned with soap and water as soon as possible and clothes should be changed in time. In addition, attention should also be paid to the temperature and humidity control of the environment and the hot stamping property of paper prints after UV varnishing

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