Thermosetting ink printing process and printing method

Thermosetting inks are fluids whose viscosity changes with the action of shear (usually including printing and stirring) and temperature. Also called pseudoplastic fluid. Its viscosity is not a constant value. With the same kind of ink, the viscosity will decrease with the effect of shear (the ink is printed more dilute); the viscosity decreases with increasing temperature (summer ink is thinner than winter). This property directly determines the adjustment method for the viscosity and printability of thermosetting inks. In general, the ink company's factory viscosity is a universal value, if there are special requirements, it should learn to adjust the viscosity according to their own printing habits.

The printability is ultimately determined by the operator's perceived print viscosity, and the operating viscosity requirements are different for different mesh counts and pattern effects. Here, we give a brief introduction to the usual adjustment methods:

1. Before using the ink, it is recommended to stir it thoroughly first, and the stirring time depends on the factory date. The delivery time is relatively long (more than 30 days), and the stirring time is about 20 minutes (Ryron ink stirrer).

2, the correct use of viscosity adjustment additives, the usual thickening method is ink special thickening powder mo-0010 and liquid thickener mo-0001, the ratio is less than 1%. In general, the ink diluent is a dedicated liquid diluent and a curable diluent. All viscosity adjustment aids should be fully stirred and should be used up on the same day.

Second, the table dry speed

The speed at which the ink is dry depends on the temperature and the formula ratio of the ink. If the formula proportion of ink is not correct, it cannot be dried at normal temperature, and it can only increase the temperature (sometimes still does not help). This is an unchangeable performance. Only good inks can be selected. Usually the slow-drying ink will have problems with sticky hands or even oil leakage. In this case, the ink should be replaced immediately.

Adding a certain proportion of low-temperature transparent ink fc-0196 (15%-30%) in the ink can greatly speed up the surface drying and reduce the surface dry temperature.

Surface equipment selection

In the automatic printing presses, an intermittent flash plate is generally used; in a better hand-printing factory, a walking drying machine is used; in Guangdong, the most surface-heating equipment is an electric air gun. Here we must specifically point out that if the walk-behind dryer is used to bake mortar, there may be problems with insufficient temperature. The solution is to add more heat pipes. In addition, lower the baking plate position.

Third, drying characteristics and low temperature curing agent fc-0880, low temperature curing ink fc series

Thermoset inks must be properly dried to produce good adhesion to textiles. Without the addition of low-temperature additives, the drying temperature is 160 degrees Celsius for the cloth (printing surface). Please note that the fabric temperature is mentioned here. If the position of the temperature probe of the tunnel dryer is different, the temperature of the dial will be different from the actual temperature. This requires temperature correction. The drying process is from the table to the inside, from the extension to the center.

The drying time is not a fixed value, but it is selected flexibly according to the size and thickness of the printing area. The usual experience is 45 seconds to two minutes. For an ordinary 8 inch square dot and color printing, 160 degrees 1 minute is enough. If it is thick printing, the drying time will be longer.

The advent of thermosetting ink low-temperature curing agent fc-0880 is a breakthrough for plastisol inks. The significance of this is to broaden the range of suitable fabrics for thermosetting inks.