One, self adhesive label stamping
1 stamping method
According to the processing method of the self adhesive label, the stamping method is divided into a single sheet of paper and a roll of paper. Single sheet of paper to the traditional hot stamping process of the same, in the special stamping machine processing. Roll paper stamping is completed on the label machine, is the most widely used one of the processing methods. At present, there are several ways to foil roll material:
The label on the flat stamping machine
Toppan labelling printing machine either flat or circular applanation - type equipment, due to the paper web occasional, so blocking all the pressure formula of the square. Under normal circumstances, the station for the independence of the unit, there are some models of hot stamping to die sharing a unit, the use of separate.
The multi station die stamping
Some models have two stations of the hot stamping units, such as the Japanese SMHC-45-MWL Shiki tag machine, one of its units close to the plate, complete the lateral stamping, the other unit is an independent unit, complete the vertical stamping. The models can be double color hot stamping.
The flat stamping processing machine
The machine is designed for processing printed web tags and labels that do not need to be printed. Hot stamping is a function of the machine, the stamping device on the machine is generally used in flat pressing square, its working principle with the label machine.
The rotary rotary bronzing machine
Round press round stamping with the gilt version for the roller, stamping and embossing roller to roll contact, to achieve. Round press round stamping is suitable for use on the continuous transmission of the wheel of the wheel, but there is a certain requirement for the speed of transmission, which means that the speed of printing. But relative to the flat stamping, greatly improving the efficiency. Round foil stamping roller manufacturing cost is high, so it is only suitable for long version of live hot stamping.
The rotary cold stamping machine
This is a new process of hot gold, no longer use the heating metal plates, but the use of printing adhesive method, so that the transfer of metal foil, to achieve gold foil. Process is: in printing need gilding position first printed on UV curable pressure-sensitive adhesive, UV drying device causing the adhesive to dry, then use special metal foil with pressure-sensitive adhesive compound, then stripping foil, so metal foil need transfer part of the transfers to the printing surface, for cold stamping. Cold stamping process is low cost, energy saving, high production efficiency, can make use of existing equipment components, no need to add additional equipment, is a very promising new technology.
Two, self adhesive label UV glazing
Glazing technology is mainly used in coating the surface of a mirror coated paper, coated paper labels to increase the surface gloss, and achieve the role of anti fouling, anti moisture, protection pattern. According to the processing method, self adhesive label material is divided into a single sheet of paper polishing and web, in which the web is the most widely used in the label printing process.
Roll paper label is on the turn of the wheel on the label machine. At present, the common use of UV glazing process, namely: in the printing of the surface evenly coated with a layer of UV varnish. For water-based ink flexo printing labels, glazing is an indispensable step.
UV glazing process should pay attention to the following matters:
1 polishing oil quality test
UV glazing oil varieties, a certain storage period, and has certain requirements on the environment, so that Sichuan before use should check glazing oil color and quantitative coating after drying, and the matching of additives, but also pay attention to the observation and the printing ink of reaction. General requirements for glazing test, and then put into normal production.
2 on the thickness of light oil
UV glazing oil is not as solvent based varnish, if the amount is too large, it will make the surface of the surface appear stripes, affecting the effect of light reflection. Coating amount is too large will make polishing oil dry is not completely dry, only the surface dry, resulting in re roll after adhesion.
3 polishing oil viscosity and surface tension
The viscosity of polish oil has influence on its leveling characteristics, drying rate and surface gloss. According to different paper, adjust the appropriate viscosity. In the control of viscosity, but also pay attention to the change of surface tension on the polishing oil. To make varnish surface tension is less than printing ink layer surface tension, so that varnish can completely wetting surface polishing, avoid stythe eye of a needle, streak and other quality problems.
4 speed, coating amount, pressure, drying temperature
Coating speed, coating amount, pressure and drying temperature of the four are mutual constraints, the need to be based on the different surface of the paper on the wetting and absorption of light oil, a reasonable adjustment of the relationship between them.
5 regularly check UV drying device
UV drying device in the ultraviolet lamp with the extension of the use of time, the effective power is gradually reduced, the general UV tube is 1000 hours of effective time. The effective power of the production should be regularly detected, when the use of time is close to 1000 hours should be replaced in a timely manner.
2 first and after the hot stamping
Adhesive for the first and then hot stamping, stamping is the first in the label on the first hot stamping, and then printing; and then the first stamping, and finally re - stamping. The key to hot stamping and post hot stamping ink drying problem. The relationship between stamping designs and printing patterns of the two types: parallel and overprint. Due to the use of different ink, label printing to be used in the first and then after the two kinds of gold foil stamping process.
First stamping process
Using an intermittent lose paper stamping parts installed in before labeling machine using the common ink printed label, the stamping process, due to the use of ink for oxidative polymerization drying, printing ink layer