The effective way to improve the printing effect

With the development of social economy and the improvement of people’s living standards, people are paying more and more attention to the perfection of commodity packaging. Corrugated carton packaging has a growing share of the entire packaging industry with its unique features. The key technology of corrugated cartons lies in the printing of ink and ink. This article talks about how to use the equipment improvement to improve the quality of ink printing.

First, printing dew treatment

Printing luster is the most common and most difficult quality problem in the production of corrugated cartons. Its causes are: poor ink absorption properties of the paper; dirty printing plates; paper scraps, dust, etc. on the cardboard. The traditional approach to these problems is to change boxes manually or to increase the frequency of manual printing. These methods will play a role in the objective, but the improvement effect after the change of the box is not great, and it is easy to cause the efficiency to drop; the version will also cause water, electricity, and artificial waste.

After a long period of observation and analysis, the author believes that in the process of equipment installation, maintenance and management, the key to solving the problem of printing and whitening is dust removal. The main source of dust was generated by single-blade paper separation. Based on this situation, the author installed electrostatic suction and dust collection devices on computer horizontally after the cross cutting knife of the cardboard production line and the paper feeding section of the printing press two years ago. A hair dryer is used before the cutting knife to blow out or blow off the paper scraps hidden in the pit pattern when the single knife is divided, and then the paper scraps are sucked by the electrostatic suction dust suction device at the delivery rack after the computer cross cutter. go. In the paper feeding section of the printing press, the dust on the paperboard is sucked away by the electrostatic dust to keep the printing surface clean and dustless. In this condition, when the paperboard enters the printing roller, ink is applied. Barrier-free, uniform ink absorption. After such improvements, the printing effect of the product has been greatly improved, and the phenomenon of printing and whitening caused by dust has been fundamentally overcome.

Second, the processing of overprinting

Nowadays, more and more attention has been paid to the artistic and three-dimensional appearance of the patterns in the packaging of goods so that consumers can feel the perfection of the purchased goods from the packaging. To achieve this goal, packaging printing must use multi-color printing, that is, multi-color overlay.

In the overprinting process, there often occurs the overlap between the latter color and the previous color, or the positional position is misplaced, so that the printing pattern cannot reflect the design effect of the product packaging, and even diverges completely, completely destroying the image of the product.
In response to this particular problem, the author's company has conducted in-depth field investigations for a period of time, performed detailed calculations on the speed of electronic control and the accuracy of mechanical fit tolerances, and performed various improvements on existing equipment, and developed related Equipment maintenance measures.

1. Improve the accuracy of printing drum phase positioning

The phase position of the printing cylinder is controlled by the encoder and counter. If the precision of the counter is too low, the position of the encoder will be inaccurate.棸鉩ounter reflects the speed of 3K, but it often produces an error of ±1mm during positioning. After consulting with Taiwan Electric Control Co., Ltd., it produced a counter of 5K, which reduced the printing roller positioning error to ±0.4mm.

2. Timing lubrication, testing transmission machinery

In the paper feeding process, if the transmission machinery can not maintain a good and smooth operation, the position of each paper board arrives will change, resulting in printing and positioning the position, so it is very important for the correct maintenance and testing of the equipment. . A daily commissioning checklist can be developed for daily startup work, including lubrication maintenance. At the same time, the limits for the amount of wear of the paper feed roller and the paper feed ring are defined. If it fails, it must be worn and re-wrapped or replaced to overcome the phenomenon of the board walking and the oblique position during walking.

3. Using suction paper feed

The traditional printing press adopts the upper printing and can only use the paper feeding wheel to convey the paperboard, while the new printing press adopts the advanced technology of lower printing and upper suction air conveying the paperboard. The suction paper feed uses the wind to suck the paperboard on the transfer wheel. The suction force is uniform, the position is not taken, and the position is not inclined. The curved paperboard is evenly leveled, the printing level is right, and the ink is evener and flatter.

Third, printing ink bad treatment

Ink problems In addition to paper and offset problems, there are technical problems with the ink roller on the device.

Anilox roller is used in the anilox roller, in the high standard carton printing, using 250lpi anilox roller, the mesh hole is most likely to be blocked by ink residue, resulting in uneven ink, ink is not enough, light ink and so on phenomenon. The traditional method is to use clean water to clean the ink roller. No matter how the water scrubs the ink roller or the scrubbing method, the effect is not ideal. A new ink roller is used for less than a month, and the effect is obviously not as good as before.

The author's company, through long-term exploration and experiments, believes that the following methods can effectively solve the problem of poor printing ink.

1. Add a filter in the ink tank to prevent the ink particles from being transferred to the ink roller.
2. Regularly (usually two weeks) use an anilox roller cleaner to perform cycle cleaning.
3. Every day after work, use a dripping water circulation to clean the ink roller, and use a magnifying glass 60 times to 100 times to dial the mesh of the ink roller. There should be no residue of the ink residue. If there is residual ink residue, it should be immediately cleaned with a deep cleaning agent.

Through the above points of maintenance, the inking ink roller effect can always be maintained.

The above-mentioned several printing technical problems are crucial to the quality of the carton products in actual production. Through the recognition and improvement of the equipment and good maintenance, the products that the customer is satisfied with can be produced and the comprehensive benefits of the enterprise can be improved.

Source: Shanghai Jinchang Carton Machinery Manufacturing Co., Ltd.