Usually anti-counterfeiting printing is used In all kinds of high-end tobacco, wine, cosmetics and other packaging materials processing. Compared with the traditional molding roller heated by heat transfer oil, the product not only has more uniform temperature, but also reduces energy consumption by 50% - 70%.
Production and application of laser film anti counterfeiting printing
1. Background
Laser molding machine is the most important equipment in the field of laser anti-counterfeiting printing. Its working principle is: under the condition of high temperature and high pressure, the information on the laser die plate on the plate roller is transferred to the film substrate or special coating, forming uneven and different size light refraction points. After illumination, the diffuse reflection of different wavelengths will make the laser film show rainbow light. When pressing laser graphics and texts, it is necessary to master the three elements of temperature, speed and tension. If the control of these three elements is not accurate enough, serious quality defects such as color difference, black spots, white spots, water lines, wrinkles, cloud flowers, pitted laser graphics and light column deformation and unstable tension will be produced. These defects will bring trouble to the subsequent printing, and even make the laser film unable to be put into the next production process.The common laser molding machine consists of four parts: unwinding section, preheating section, traction section and winding section. In the production process, the temperature, speed, tension three elements, speed and tension after the adjustment is relatively stable. The preheating roll and plate roller are heated by heat transfer oil circulation. The principle of this heating method is simple and the manufacturing cost is low. However, the rotary joint is easy to leak, the heat transfer oil is easy to coking, and the electric heating pipe is replaced frequently. The surface temperature of the roller is uneven after long-term use, which has a great impact on the product quality.
2. Existing technology defects:
1) Serious pollution: heat transfer oil will continue to volatilize into the air during heating. At the same time, the leakage of heat transfer oil will occur after the rotary joint is used for a period of time, which will not only pollute the air and ground environment of the workshop, but also affect the product quality. Meanwhile, the outflow of flammable heat transfer oil medium is easy to cause fire and other unsafe factors.
2) Low accuracy of temperature control: heat transfer oil is easy to oxidize and coking after long-term use, resulting in uneven heating of roller body and large temperature difference of roller surface, thus affecting product quality.
3) High energy consumption: the heating of heat transfer oil is completed by electric heating pipe. After heating, it enters into the internal circulation of roller body and pass through a section of oil pipeline during this period. In this process, the heat is emitted to the air, causing a large amount of loss.
Meanwhile, 2 ~ 3KW oil pump works continuouslyto keep the circulation of heat transfer oil. The its energy consumption is considerable.
d. Heavy workload of repair and maintenance: working under long-term high-temperature, heat-transfer oil is easy to produce carbon deposition and scale on roll wall, oil core, electric heating tube, oil tank, etc., which requires regular replacement of heat-transfer oil and cleaning of roll wall and oil path, oil core, electric heating tube and oil tank. In addition, rotary joints, seals, high-temperature oil pumps, heaters, high-temperature valves and other accessories also need regular maintenance and replacement, resulting in high maintenance costs and huge shutdown losses and manpower losses.
3. Solution:
The induction heating molding roller is used to replace the existing heat transfer oil heating roller.