Three problems affecting the quality of Cigar Paper Boxes With Ribbon printing and their solutions

Three problems affecting the quality of Cigar Paper Boxes With Ribbon printing and their solutions

The treatment of printing exposure in flexo printing, the treatment of overprinting out of position, and the treatment of poor ink on printing

First, the processing of printing exposure

Printing exposure is the most common and the most difficult to eliminate quality problems in the production of corrugated boxes, the reasons are: paper ink absorption performance is poor; Plate dirty; There is debris, dust, etc on the cardboard. The traditional way to deal with these problems is to manually change the box, or increase the frequency of manual erasers. These methods will play a certain role in the objective, but after changing the box improvement effect is not big, and easy to cause efficiency decline; The plate will also cause water, electricity, artificial waste.

After long-term observation and analysis, the author believes that in the process of equipment installation, maintenance and management, the key to solve the printing dew is dust removal. Dust is the main source of single pole points when the paper, based on this, the author in cardboard production line computer cross-cutting knife after two years ago and the printer paper department has installed the electrostatic suction aspiration device, use the hair drier, in front of my computer cross-cutting knife to monolithic knife hidden in the grooved as "paper about dust blowing out or blow away, Then the paper scraps are sucked away by electrostatic suction device at the paper holder behind the computer crosscutting knife. At the gap between the paper feeding apron and the paper feeding wheel in the paper feeding department of the printing press, electrostatic dust is used to absorb the dust on the paperboard, so that the quality printing surface is clean and dust-free. Under such conditions, when the paperboard enters the printing roller, the ink is smooth and uniform. After such improvement, the product printing effect greatly improved, and fundamentally overcome the dust caused by the phenomenon of printing white.

Second, the processing of overprinting

Now commodity packaging is paying more and more attention to the artistry of the design, three-dimensional sense, so that consumers feel the perfection of the goods purchased from the outer packaging. To achieve this purpose, packaging printing must be multi-color printing, that is, multi-color overprinting.

In the overprinting process, the latter color is often superimposed with the former color or the positioning position is misaligned, so that the printing pattern can not reflect the design effect of the product packaging, or even completely destroy the image of the product.

In view of this special problem, the author's company, after a period of in-depth field investigation and research, has carried out a detailed calculation of the electrical control reflection speed to the mechanical fit tolerance accuracy, has carried out a number of improvements to the existing equipment, and developed relevant equipment maintenance measures.

1, improve the precision of printing drum phase positioning

The phase positioning of the printing drum is controlled by the encoder and the counter. If the accuracy of the counter is too low, the position of the encoder will be inaccurate and the position of the encoder will be out of place during printing. Poly 鉩 ounter reflect the rate of 3 k, but often in the positioning error of plus or minus 1 mm, after discussions with Taiwan electronic company, producing 5 krcounter, printing roller positioning error was reduced to + / - 0.4 mm.

2, timing lubrication, testing transmission machinery

In the process of paper feeding, if the transmission machinery can not maintain a good and balanced operation, the position of the cardboard will be changed every time, resulting in printing and positioning, so the correct maintenance and detection of the equipment is very important. Can develop a daily pre-startup test checklist, including lubrication maintenance. At the same time, the limit of wear of the paper feeding wheel and the paper feeding ring should be established. In case of unqualified, it must be turned over, re-coated or replaced to overcome the phenomenon of the position and oblique position of the cardboard in the walking process.

3. Adopt air suction and paper feeding

The traditional printing machine adopts upper printing and can only use the paper feeding wheel to transmit the cardboard, while the new printing machine adopts the advanced technology of lower printing and upper suction to transmit the cardboard. Air suction paper feeding uses wind to adsorb the cardboard on the transmission wheel, its suction is uniform, does not move, does not tilt, and the curved cardboard will be sucked flat, printing alignment, ink more uniform, more flat.

Three, printing ink bad treatment

Ink in addition to paper and offset problems, in the equipment and ink roller technical processing problems.

In the printing of high standard carton, the roller with more than 250lpi is used. The mesh of the roller is most likely to be blocked by ink residue, resulting in uneven ink, insufficient ink amount, and shallow black. The traditional method is to use water to clean the upper black roller. No matter how to clean the upper ink roller with water or cleaning agent, the effect is not ideal. A new upper ink roller can be used for less than one month, and the effect is obviously worse than before.

Through long-term exploration and experiment, the author's company believes that the following methods can effectively solve the impact of bad ink on printing.

1. A filter screen is installed in the ink bucket to prevent ink particles from being transmitted to the ink roller.

2, regular (generally half a month) use roller deep cleaning agent, cycle cleaning.

3. Clean the ink roller with a drip cycle every day after work, and dialyse the mesh of the ink roller with a magnifying glass of 60 to 100 times. There shall be no residue of ink residue.