UV Ink
1. Adjustment of indoor temperature
UV type ink has the property that its viscosity changes sharply with the change of air temperature. This viscosity change will have a great impact on the printing adaptability and the thickness of the printing film. Generally, when the ink temperature decreases, the viscosity increases and the film thickness becomes thicker. If the viscosity of the ink changes too high and the permeability of the screen deteriorates, the printing film thickness will result in foaming and more porosity. Therefore, please keep the room temperature at a constant temperature as far as possible during printing, generally 18-25°C is appropriate. A little ink, the printing site will absorb moisture when the humidity is high, and problems such as viscosity and gel will occur. At this time, it needs to be treated with air conditioner or dehumidifier.

2.
When using common colored inks, a version with a 300 mesh or above and a sol thickness of less than 10UM shall be used. Under these conditions, the thickness of the printed ink film is 10-12UM, and the printing area can reach 70-80 square meters/kg. If colorless varnish is printed, the result of thick film can be printed by using a low-screen plate, and the screen plate can be selected according to the purpose.

3. Scraper
A polyurethane scraper with a hardness of 65-80 should be used with sharp edges. The monomer contained in the ink will cause the scraper to swell, so it is necessary to grind or reverse the scraper.

4. Viscosity adjustment
After full stirring, take it out of the ink tank and print it directly. According to the purpose, if it is necessary to reduce the viscosity of the ink, a thinner within 10% should be added. On the contrary, if it is necessary to improve the viscosity, should be mixed in matting varnish (high viscosity, increased viscosity) or add 1A-244, JAR-20 and other powder matting agent, in full stirring after printing use.

5. Concentration adjustment
When adjusting the concentration, clear varnish (CLEAR) or colorless concentration adjuster (EXTENDER) should be added.

6. Influence of light
During the printing process or the cleaning process of the plate, direct sunlight should be avoided. As long as the light of fluorescent lamps is not very close, there is generally no problem.

7. Standard Curing Conditions
Each series of inks has its own standard curing conditions. Refer to the standard curing conditions recorded in the product specifications of each series of inks.

8. Preliminary test
The curing conditions in formal printing vary depending on the printing materials and printing conditions. Different manufacturers and models of UV irradiation machines will also cause differences in curing. Therefore, the preliminary test must be carried out according to the same conditions as the printing production line to determine the curing conditions. The procedures for the preliminary test are as follows:
After printing ink on the printing material, pass through the UV irradiation machine under standard conditions;
Then test the remaining marks, adhesion, scratching and bending of the printed surface;
If the test results fail, it is necessary to adjust the various conditions of the irradiation machine until satisfactory results can be obtained. During the test, it is recommended to use a UV accumulation light meter for measuring the amount of light.
9. Printing Preheating
When printing on materials that are not easy to adhere, after printing with ink, preheat should be carried out before UV irradiation. Preheating with near infrared, far infrared, etc. for 15-90 seconds will greatly improve the adhesion.