The Practice of Web Bronzing with Web Connection

In many packaging printing production processes, hot stamping operations are often encountered, especially with the increasing number of anti-counterfeiting requirements, hot stamping anchor marks become more common. Colorful packaging products are easy to cause people's visual attention, but also can improve the taste and grade of packaging products.

Modern mass-produced packages are required to be completed on gravure and flexo presses. The materials used are reel materials and the production speed is fast. This requires hot stamping films to be produced rapidly (up to 60 m/min or more). Complete 100% transfer in time. At the same time, since the bronzing operation only occupies a small position on each small package, the galvanized aluminum bronzing material must be consistent with the printing speed when hot stamping. If no technical measures are taken, bronzing materials will be greatly wasted. Due to the large length of each roll of printed material and the small size of each roll of bronzing film, it cannot be matched to the production. Even if the lengths of the two materials are the same, there is a contradiction that the galvanized aluminum must skip work.

The flat stamping hot stamping mechanism is a problem that cannot be easily solved because the printing material needs to be stopped periodically on the hot stamping table, and the position of the stamping quality should be accurately reached at each stop position.

In the normal course of the printing material, if it is moving at a speed of 100 m/min, if it is made to move at the same speed in the reverse direction, it can be a stationary state in the space position, that is to say a double roller swing frame can be used. The periodic positive and negative movements require that the stroke length of the positive and negative movements be the same as the length of the print, requiring that the printed space be stopped at a fixed point for a period of time for hot stamping, but the mechanically reciprocating swing mechanism is generally realized by the crank connecting rod. The movement of the crank is obtained by the average speed rotation of the eccentric. The speed curve of the crank movement is a sinusoidal curve, that is, the speed is the minimum at the starting point of 0° and the ending point of 180°, and is the maximum at 90° and 270°. It is a non-uniform movement. .

Then, when the printed matter is stationary on the hot stamping workbench, it is only relatively stopped near the two phases of 45° and 135° during the work process, and the hot stamping operation cannot be completed. In order to solve this problem, Xi'an Heiniu Machinery Co., Ltd. adopts an exchange. Servo motor 360° cycle operation Non-uniform mode software programming for 180° working process, and through trial and error modification to enable it to completely reach relative standstill from 45° to 135° during operation, such as a hot stamping cycle time For a 400ns (150 beats/min) hot stamping process, the 180° hot stamping process takes a total of 200ms for a 180° hot stamping process. If the phase is between 45° and 135°, the AC servo uses a non-uniform speed to achieve a uniform speed of 100ms. Finishing hot stamping is more than enough.

In 2002, the author saw the production of Komori Shangbang gravure printing equipment produced in France. There was a station of continuous round hot foil stamping units. When the speed reached 100m/min to 120m/min, the hot stamping was still working properly, and hot stamping was also performed. It is clear that Komori Shangbang Machinery has successfully solved the synchronizing and skipping of the speed of the bronzing film in the round-pressing operation, so that the bronzing film can be used without waste. The method is simple and reliable. Using a small inertial arm, the swing is a quarter of the length of the packaged printing unit. As the hot stamping copper plate is pressed during hot stamping, the hot stamping film and the printing object are pressed against the supporting roller, under the double action of pressure and heat, The transfer is realized. At this time, the bronzing film must run at the same speed as the printed material. When the hot stamping point left after the hot stamping is completed, the galvanized aluminum film will not be pressed before the next stamping. The film is returned to a length, so that the hot stamping film can be fully utilized during the continuous hot stamping and the hot stamping film can be greatly saved. However, its structural characteristics only solve the problem of waste of anodized aluminum, and it cannot solve the hot stamping of laser hot stamping materials.

Due to the development of science and technology, the domestic hot stamping film has also developed to low-temperature cold-hot stamping type. The bronzing film matching the Shangbang machine has been able to be supplied in domestic facilities. Domestic materials with high-speed hot stamping enable Xi'an Black Niu to develop a research roll. The idea of ​​circular press hot stamping in operation.

Because there are two problems that cannot be solved before round round hot stamping: One is how to solve the problem of waste of hot stamping film: one is the quality problem of hot stamping when working at high speed. If the above two problems can be solved, then the round press mechanism itself The characteristics will be clearly revealed, mainly due to its simple structure, small space occupation, short process adjustment time, low cost, and easy popularization of technology.

Shenzhen Jingjia Printing is one of the leading printing and packaging enterprises in China. In 2003, it imported a hot stamping unit for the quick replacement of the printing group for its Heidelberger compact press. Through the Swiss engineers, it stamped its products. Debugging has successfully achieved a hot stamping at 80M per minute. Since the company mainly manufactures cigarette packets, and the production of soft packets is produced with laser transfer paper, it can be used for laser paper seam processing in the future. There are seams imposition methods, but due to the difficulty of the AC servo motor to send hot stamping materials and positioning in the middle of each interval, the computer processing time is extended, so the hot stamping speed only reaches about 70 meters/minute. The printing speed is adapted to the level. If the bronzing method is evenly arranged on the circumference, the gold speed can be increased to 90 meters or even 100 meters per minute.

As Xi'an Black Bull used the AC servo motor to handle the paper feeding process of the flat stamping hot stamping machine, it was recognized by Shenzhen Jin Jia and Xi'an Black Bull was commissioned to research and manufacture the round press hot stamping mechanism. In the new design, we removed the aluminum alloy cleats used for unwinding, making it easy to replace new rolls and remove waste rolls. The roll-up common common motor is used to wind through the torque slip method. The unwinding takes into account the hot stamping. The precise positioning of the laser anti-counterfeiting mark in the job is still using a single single-motor positioning drive feeding method, and the eccentric common swing roller method is boldly adopted on the hot stamping intermittent feeding, which greatly simplifies the original mechanism, and the AC servo motor used is reduced to 6 The station greatly simplifies the line and facilitates customers.

As the design is simplified, the use is convenient, the cost is reduced, and the web round press hot stamping mechanism can be used on both gravure printing and flexo printing, so that the domestic web connection hot stamping production process has A practical organization, and because of the lower cost, can be widely used in the printing industry.