Quick Drying Water Based Varnish

Quick Drying Oil

The composition of water-based varnish and the surface properties of printed matter also affect the determination of drying time and drying temperature. When the printing surface has strong absorption, the penetration of small molecular substances in the waterborne varnish coating layer is strengthened and the drying speed is improved. The drying time and temperature should be appropriately shortened.

The relative temperature of the printing environment also has a certain impact on the selection of drying conditions. The reasons are: first, the moisture in the air enters the coating layer during the coating process, which affects the comprehensive volatilization rate of the solvent. Second, there is a large amount of water in the air, which inhibits the volatilization of the solvent. When other conditions remain unchanged, the temperature is doubled and the drying time is nearly doubled. Therefore, when the air moisture content is high, the drying temperature and drying time should be increased as much as possible.

During polishing and coating, the drying conditions shall be controlled according to the above characteristics, including the drying temperature, air volume and drying device conditions. If the coating is not completely dried, the solvent volatilizes incompletely, the amount of solvent remaining in the film exceeds the requirements, the polishing effect decreases, and the solvent is subject to thermal expansion or volatilization during polishing, which is prone to bubbles or sand holes and adhesive calendering belt, If the drying is excessive, the deformation value of the film increases or softens, and the printed matter is brittle.

The control of drying time can be realized by changing the distance of drying mechanism or coating speed. The control of drying temperature of water-based varnish is realized by adjusting the power of heating source of drying mechanism. The velocity of air in the drying channel has a certain influence on the drying of the coating. In solid heat conduction drying, too high air flow rate will reduce the drying temperature. In radiation drying, on the basis of ensuring the reasonable distance between the drying source and the dried coating, the principle of air flow rate selection is to minimize the absorption rate of rays.

Precautions for use of water-based varnish:

1. Due to the complete curing of Waterborne Varnish, its appearance is very smooth and rarely sticky. Unlike other gloss agents, everything is in use, and the use of UV anti adhesion agent can be completely cancelled or reduced.

2. When using water-based varnish, pay attention to the performance of the paper. Thin paper has poor dimensional stability and thick paper has good dimensional stability. Because dimensional stability is one of the key indexes of printing quality. The amount of water in printing, the humidity regulation of paper, the monotonous time and mode and the control of viscosity are closely related. In all operations, water-based varnish shall be used with care.

3. Viscosity control is particularly important. The ethanol content should be increased in time to ensure the stability of the product. In the coating process, the dilution can only be carried out within a certain solid content range, and the viscosity and solid content of UV varnish must be reasonably controlled.. Ethanol and water are usually used as diluents. The viscosity reduction effect of aqueous varnish is obvious, and the use proportion should be strictly controlled Zhongzhixing matte water-based varnish environmental friendly water-based ink has fast drying speed and strong weather resistance.

4. The coating amount of water-based varnish is relatively difficult to control. Ethanol volatilizes very fast on the coating, while water is colorless and transparent. It is difficult to distinguish the transparent water-based liquid on white paper with the naked eye. UV varnish is a common surface decoration process in packaging and printing industry. Officially, it is difficult to observe the production state with the naked eye. When using varnish on the surface, special processes such as fluff feeling and bronzing feeling will be used, which puts forward higher requirements for the difficulty of operation.

Hot Tags: quick drying water based varnish, China quick drying water based varnish manufacturers, suppliers, thinning water based varnish, solvent based polyurethane varnish, extra strong varnish, Matte Water Based Varnish, non water based varnish, water based conversion varnish