Currently, the hot stamping machines available on the market for paper processing can be classified into three categories based on their working principles: flat-flat, round-flat, and round-round. The hot stamping and die-cutting dual-purpose machine is currently the most popular flat-flat hot stamping machine model, and the most commonly used manual hot stamping machine also belongs to this category. Among these types of hot stamping machines, each process has its unique characteristics and cannot be simply deemed superior or inferior to the others.
Flat-Flat
In the packaging and printing field, the flat-flat hot stamping process is most widely used because the equipment typically possesses both hot stamping and die-cutting functions. For users, when the hot stamping business volume is unstable or insufficient to ensure full-load operation of the equipment, using a flat-flat hot stamping and die-cutting dual-purpose machine can ensure investment efficiency. In terms of the process, flat-flat hot stamping is also the most mature hot stamping process, with hot stamping plate production supported domestically. In addition to general flat hot stamping plates, three-dimensional engraved hot stamping plates can also be produced, achieving hot stamping and embossing in one step. The production speed of high-speed flat-flat hot stamping machines has currently reached a relatively high level. However, the flat-flat process also has its drawbacks. For example, the effect of large-area hot stamping is not as good as the other two processes because the pressure in flat-flat hot stamping machines is surface pressure, while in round-flat or round-round hot stamping machines, the pressure is linear.
Round-Flat
Round-flat hot stamping uses a flat hot stamping plate and a round impression cylinder. The flat hot stamping plate is easy to produce, while the round impression cylinder allows the stamping pressure to be linear, compensating for the shortcomings of the flat-flat hot stamping process. The disadvantage of round-flat hot stamping is that it cannot achieve hot stamping and embossing in one step. Additionally, the production speed is relatively slow, typically between 2000-2500 sheets per hour. In European and American countries, printing plants specializing in hot stamping usually have both flat and round-flat hot stamping machines. These two processes complement each other, overcoming their respective shortcomings and meeting the needs of different designs.
Round-Round
The greatest advantage of round-round hot stamping is its high speed. However, the drawbacks of round-round hot stamping are also quite significant. Firstly, the hot stamping plate is not only expensive but also requires high precision. It must consider the thermal expansion coefficient of the material and the wear of the plate, among other factors. Secondly, the hot stamping foil also has special requirements; it must be capable of quick transfer. Currently, domestically produced aluminum foil can hardly meet this requirement, necessitating the use of expensive imported special materials. Otherwise, the high production speed remains an empty promise. Additionally, hot stamping and embossing must be achieved in two separate units, requiring at least two sets of molds, which invisibly increases the cost. Furthermore, if market demand changes and the hot stamping business volume decreases, the high-value equipment may become useless, representing a significant investment risk.
