Development trend of the hottest printing and poli

Development trend of printing and polishing machinery

printing and polishing machinery is divided into polishing machine (including calender) and printing and polishing linkage machine. Domestic polishing machine is generally operated by a single machine, with slow processing speed and low quality. Therefore, it is often necessary to perform calendering treatment again. While foreign large offset printing manufacturers mostly adopt printing glazing, that is, they connect the machine on the basis of equipped with different fixtures, so as to improve the glazing speed and quality. Printing glazing linkage machine is the development trend of glazing machinery

first, the printing and glazing linkage machine

the basic form of the printing and glazing linkage machine is to use the wetting device of the last printing unit of the sheet fed offset press to refit, the original ink supply system is disengaged, and then the paint is printed; Or add a coating roller device on the rubber drum of the last printing unit of the offset press, so that the glazing paint is first coated on the rubber and then transmitted to the print; Another is to add a coating mechanism between the final printing unit of the original multicolor offset press and the paper receiving unit; In foreign countries, the method of "glazing and back printing" has also appeared. The front side of the paper is polished and the back side is printed at the same time. China's printing and glazing machine is still very backward, and needs to be improved to catch up with the world's advanced level

II. Water based glazing coatings

because organic solvents are easy to pollute the environment, dispersed water-based glazing coatings have been widely used in Europe and are gradually used in China. This glazing coating is composed of 45% synthetic resin and 55% water. 3. Tensile test motor: it has high transparency, non-toxic, no organic volatilization, and can be biodegradable after being discarded, without causing environmental pollution. The printed matter coated with this glazing paint will not turn yellow and discolor for a long time, and is especially suitable for the surface decoration of food, cigarettes, cosmetics, medicine and other product packaging. Add color materials to make special glazing oil, and add a certain proportion of gold or silver metal color materials to make gold or silver glazing oil, which can improve the artistic charm of glazing. At present, water-based glazing plays a dominant role in linkage machine glazing

third, tighten the lock nut and connecting nut after double glazing to eliminate the gap. Smooth head device

because ordinary ink is insoluble in glazing oil, double glazing device (two smooth heads, infrared drying) is very necessary. In addition to coating the base color and UV glazing liquid, the double glazing device is also used to coat double-layer thick foaming glazing oil, microencapsulated spices, scratch and peel lottery tickets and various kinds of package glazing

IV. corrugated roller cavity glazing

when selecting the linkage machine glazing system, it is necessary to decide whether it is double roller glazing or corrugated roller cavity glazing. The latter can accurately control the thickness of the glazing coating, does not depend on the printing speed, and is rarely affected by the viscosity fluctuation of the glazing oil. A typical glazing device is the closed doctor blade system, which is composed of ceramic grain roller, closed doctor blade and flexible resin coated plate roller. This online polishing is fast and efficient, and the corrugated roller can be replaced quickly. Selecting different corrugated rollers can accurately complete the coating as required, which can not only obtain a full glazing coating, but also carry out accurate local glazing; It also provides full expression space for pearlescent glazing process

v. unshaded paper receiving and holding teeth system

UV glazing on the sheet fed printer requires a unshaded paper receiving and holding teeth system on the printer to avoid shadows on the paper that has been polished during drying, resulting in places that cannot be exposed to UV light cannot be dried

VI. special device at the paper receiving end

the paper receiving end of the printing machine should be treated at high temperature and resistant to corrosion to avoid damage by the UV drying system. The paper guide gauge of the receiving part makes the printing sheet float forward on the air cushion. These paper guide gauges need a water cooling jacket to remove the heat from the receiving part