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The traditional heating method of bronzing machine, how to improve the efficiency of bronzing

Traditional hot stamping machine heating method

At present, the heating method of the web bronzing equipment (the web circular pressing hot stamping machine or the web flat pressing and bronzing machine) is to fix the hot stamping version (arc version, flat ironing version) on the heating honeycomb version seat. Conductive heating is carried out (generally 50-250 ° C, adjustable), and then the temperature and pressure of the bronzing plate are used to adhere the fusible thermoplastic glue in the electrochemical aluminum to the printing material, thereby completing the transfer of the electrochemical aluminum.

1 defects in traditional heating methods

In the actual production process, due to the difference in temperature control performance of the equipment itself, the difference in quality stability of the electrochemical aluminum, the change in the ambient temperature, and the fluctuation of the surface tension of the printing material (such as varnish, ink), the actual hot stamping process often occurs due to electrification. Quality problems such as hair loss and defects caused by poor aluminum film removal affect the hot stamping efficiency.

2 traditional solutions and their problems

In view of the above problems, it is generally solved by heating the plated plate, reducing the production speed, and replacing the electrochemical aluminum. However, these methods have the following constraints and cannot be completely solved.

(1) The current maximum temperature of bronzing equipment can only reach 250 °C, and it is more difficult to warm up.

(2) The overall heating method of the hot stamping plate is not flexible, and it is not possible to independently position and heat up a certain position independently. Some just adapted positions will have new hot stamping problems due to the temperature rise.

(3) will increase energy consumption, which in turn increases costs.

(4) The purpose of reducing the speed is to extend the hot stamping time and transfer more aluminum, but it will significantly reduce the production efficiency.

(5) The method of replacing the anodized aluminum has high requirements on the quality of the anodized aluminum, and frequent replacement will result in multiple shutdowns, resulting in a large amount of waste.

improve proposals

In view of the above problems, the author believes that the traditional heating method can be broken (heating only for the hot stamping plate), and the method of locally controllable heating of the Hot stamping paper is adopted as an innovative supplement and perfection of the traditional hot stamping scheme to solve the hot stamping temperature. The problem of insufficient rise or uneven temperature.

specific plan

Make an online preheating device, including 3 to 6 movable plug-in hot air generators, infrared temperature feedback sensor, 1 set of fixing brackets, and thermostat. Before the printing material (paper) enters the hot stamping cylinder, The position of the paper to be stamped is preheated. The schematic diagram of the bronzing preheating device is shown in Figure 1. The structure of the paper preheating device is shown in Figure 2.

1 preheating purpose

(1) Increasing the surface temperature of the paper, generally the surface temperature of the paper without preheating is between 22 and 28 ° C, and the surface temperature of the preheated paper can reach 50 ° C, which is equivalent to a temperature of 0 to 20 ° C. Lifting can effectively compensate for the problem that the bronzing plate temperature cannot continue to rise and the local temperature is not uniform.

(2) By preheating, the surface tension of the paper to be stamped can be changed, so that when the printing material enters the hot stamping station for hot stamping, the anodized aluminum glue layer can better adhere to the surface of the paper, thereby reducing the removal of the aluminum Quality defects such as hair loss and defects caused by poor film.

2 paper preheating precautions

It is generally recommended that the preheating temperature be around 50 °C and below. If the temperature is too high, the paper will be deformed. Multiple independent preheating devices can be made, which can be moved and selected flexibly. Each preheating unit can also perform separate temperature regulation according to the actual situation to prevent reasonable regulation when the temperature of the equipment is not uniform.

Improvement effect

After being used on the Stoly Web 820 round stamping and bronzing machine, the device solves the hot stamping temperature limit compared with the current single hot stamping heating method, changes the surface characteristics of the printing material, and improves the anodized aluminum glue layer and the printing paper. The adhesion is firm and the problem of hot stamping is reduced. According to the calculation, the machine speed can be increased by 5~10m/min, and the efficiency is increased by 20%.

There is no end to innovation, and the above methods are just a breeze. As long as the product quality and efficiency can be improved, optimization and innovation can be carried out according to the actual bronzing equipment, hot stamping materials and bronzing environment, such as pre-temperature regulation of electrochemical aluminum, etc. It is hoped that people of insight and experts in the industry will try to research and publish in many aspects. More mature and advanced insights.