Water-based photo emulsion use of eight points

1, in screen printing, to pay attention to the control of water-based photo emulsion resin parameters, including water-based photo emulsion resin viscosity, fluidity, thixotropy, and plasticity.
2, pay attention to the control index of water-based photo emulsion resin. Water-based photo emulsion resin control indexes are mainly fineness, viscosity, pH and drying speed, etc., they play a decisive role in the application of the photo emulsion effect.
3, because the water-based photo emulsion resin for the pure water-based system, so the use of water-based photo emulsion resin and alcohol photo emulsion and solvent-based photo emulsion mixed-use or add organic solvents in the ink, in order to avoid printing quality problems.
4, the use of water-based photo emulsion resin, it should be stirred evenly, measuring the viscosity of the appropriate pour into the ink tank, if the viscosity is not suitable, available thinner or thickener to adjust, and pay attention to control the pH of water-based photo emulsion resin, generally mastered in 8.5 to 9.5. printing process, due to the volatilization of water, ink resin viscosity will So we must often observe the use of photo emulsion, found photo emulsion viscosity rise or pH out of the control range, should promptly use diluent and pH stabilizer to adjust, to ensure the viscosity and pH stability.
5, in general, the ink is very suitable for high-speed printing, low-speed printing, if you encounter the drying speed is too fast or the printing effect is not good, you can add a certain percentage of slow drying agent.
6、After printing, the remaining ink resin should be taken back to the corresponding original barrel or the lid of the ink tank should be covered tightly for next use. Prevent the surface of the water-ink resin from caking, thickening, or even drying. Water-based photo emulsion resin should be stored in a ventilated and cool room with the room temperature controlled at 5~45℃.

7, after printing residual photo emulsion resin on the printing equipment when it is not completely dry can be rinsed with water, can not be washed with a clean water-ink available cleaning agent for cleaning.

8, ink resin printing suitability by printing conditions, substrate surface characteristics, environmental temperature and humidity, the length of storage, and other objective conditions, so in use, the need to use some additives to make minor adjustments to the ink to obtain the best printing effect. Water-based photo emulsion resin in the commonly used additives are color, pH stabilizer, slow drying agent, defoamer, washout agent, etc., printing to be familiar with the characteristics of the additives and the use of methods.
(1) color used to deepen the color, the amount should generally be controlled at 0 ~ 30%, more than 30% will make the ink in the connection material content is too low, resulting in its adhesion and wear resistance decline.
(2) pH stabilizer is used to adjust and control the pH value of water-based photo emulsion, so that it is stable at 8.0 ~ 9.5, to ensure that the water-based photo emulsion resin printing state. At the same time, it can also adjust the viscosity of water-based photo emulsion resin, and dilute the photo emulsion.
(3) slow drying agent used to reduce the degree of drying of ink resin, slow drying agent can inhibit and slow down the drying speed of water-based photo emulsion, prevent photo emulsion drying on the printing plate, reduce the occurrence of printing faults such as blocking and paste plate. Slow drying agent dosage should generally be controlled in the total amount of ink 0 ~ 10%, if added too much, photo emulsion drying is not complete, the print will be sticky and dirty or odor.
(4) watering down agent is mainly used to reduce the depth of color, the amount is not limited. However, adding a large amount of diluent may lead to a slight increase in ink viscosity, which can be adjusted by adding a small amount of diluent at the same time.
(5) Diluent is mainly used to reduce the viscosity of ink, the amount should be controlled within 3%, in order not to reduce the color depth of ink, and can keep the pH value of ink unchanged. The diluent should be added slowly while stirring to prevent the viscosity from being too low. If you add more diluent or use hard tap water to dilute it, it will produce bubbles, then you should add defoamer.
(6) water-based photo emulsion resin in the use of foam problems is the main reason for its water as a diluent, in the emulsion polymerization will have to use a certain amount of emulsifier, so that the emulsion system surface tension is greatly reduced.