Perfect hot stamping effect depends on the coordination of temperature, pressure and speed. Therefore, to control the quality of hot stamping, it is necessary to master the reasonable temperature, pressure and speed. This creates good conditions for hot stamping and ultimately ensures the quality of hot stamping.
Temperature has a very important influence on hot stamping. The temperature must be controlled within a corresponding range to enable the dyeing resin layer and adhesive to melt moderately, in order to ensure the good transfer of the aluminum layer. If the temperature is too high and the melting is excessive, the electric aluminum around the hot stamping graphics and text will also melt and fall off, producing smearing. At the same time, high temperature will cause chemical changes in the dyeing resin and aluminum layer of the electric aluminum, reducing the brightness of the hot stamping product and losing the metallic luster, and even making foggy or bubbly marks. However, if the temperature is too low and the melting is insufficient, it will also cause the hot stamping to not adhere or adhere poorly, the marks are not firm, easy to fall off or breaks and flowers appear.
Hot stamping transfer of the aluminum layer must be completed through pressure. The size of the hot stamping pressure of the automatic hot stamping machine affects the adhesion of the electric aluminum. Even if the temperature is appropriate, if the pressure is insufficient, it will not be possible to transfer the electric aluminum well to the substrate, resulting in problems such as blurred marks and flower plates. On the contrary, if the pressure is too high, the compression deformation of the padding and the substrate will be too large, and the marks will become rough, even sticking and smearing. Generally, the hot stamping pressure should be appropriately reduced to achieve the criterion of not fading and good adherence.
The adjustment of hot stamping pressure must comprehensively consider various factors such as substrate, hot stamping temperature, speed and the electric aluminum itself. Generally speaking, if the paper is sturdy and has high smoothness, the ink layer is thick, and the hot stamping temperature is high and the speed is slow, the hot stamping pressure should be small. Otherwise, it should be increased. The hot stamping pressure must be even, and if it is found that the local hot stamping is not possible or has lines or dots, it is likely that the pressure there is too small, and a thin paper should be placed on the plate to balance the pressure. The padding for hot stamping of the automatic hot stamping machine also has a greater impact on pressure. The rigid padding can make the marks clear and is suitable for sturdy and smooth papers such as copperplate paper and glass cardboard, while the soft padding is the opposite, and the marks are coarse. It is suitable for large-area hot stamping, especially for papers with uneven surfaces, poor paper flatness and smoothness. At the same time, the installation of the hot stamping foil should not be too tight or too loose. When it is too tight, the mark is missing or breaking. When it is too loose, the mark is not clear and smears.
The hot stamping speed of the automatic hot stamping machine actually reflects the contact time between the substrate and the hot stamping foil during hot stamping, which directly affects the adhesion of hot stamping. If the hot stamping speed is too fast, it will cause the hot stamping to not adhere or the marks to become blurred. If the hot stamping speed is too slow, it will not only affect the quality of hot stamping, but also the production efficiency. During the hot stamping process, speed, pressure and temperature are mutually restricted, and their process parameters are always determined in the order of hot stamping speed, pressure and temperature. First, determine the hot stamping speed. Generally, treat it as a constant and do not change it easily. Then find the corresponding hot stamping pressure and hot stamping temperature, which can simplify the operation procedure and facilitate the control of hot stamping quality.
In addition, during the hot stamping process of the automatic hot stamping machine, it is also necessary to consider whether the substrate, hot stamping plate, hot stamping machine, fixture, and pad are suitable. Finally, study the environmental conditions, including indoor temperature and humidity, substrate temperature, and indoor air cleanliness (dust content), etc. In short, hot stamping technology is a complex technological process. Only by grasping the above issues during hot stamping can satisfactory hot stamping results be achieved.