1) Printing proofing must be carried out under normal printing conditions, otherwise it will cause difficulties in tracing samples. For example, when printing proofing, the scraper is too close to the imprint line, so it is difficult to handle or adjust the scraper related faults in formal printing. If the printing sample is carried out when the scraper is far away from the embossing line, it is difficult to transfer the ink in some shallow places during the formal printing, which will produce dots on the printed matter. When the distance is shortened to eliminate these dots, the ink color will certainly change. Due to the characteristics of gravure, the color of the printed product is different under different printing speed and pressure. Therefore, the ink with low speed adjustment must be proofed again after the printing speed reaches the daily speed, so as to avoid color difference and waste.
2) Printing color control is mainly to control the mixing effect of various colors. In the specific operation, it is necessary to accurately determine which color has changed. Be careful not to patronize a local color and forget the color changes associated with it.
3) When observing the color of printing sample, it is better to carry out under the standard light source. Sometimes, even if the color looks the same under the ordinary light, it looks inconsistent under another light source. Therefore, the standard light source should be selected for color observation or color comparison. In proofing or replacement of ink batch size, especially pay attention to the same color of the ink spectrum phenomenon.
4) In the printing process, how to keep the ink color of a batch of printed matter or several batches of printed matter consistent is not only a basic requirement, but also an important problem. In the production process, the color of ink film mainly depends on the concentration and transfer rate of working ink. For a specific substrate and a specific working ink, the concentration of working ink is relatively fixed, and the transfer rate depends on the viscosity, the dryness of the working ink and the mesh condition of the layout. At the same time, it is also affected by the printing speed, printing pressure, scraper pressure, scraper position, blade angle and environmental conditions (temperature and humidity). It is necessary to point out that the influence of these conditions on the highlight, dark tone and intermediate tone of printed matter is different.
Sometimes the printing process is not always ideal, and some factors have to be adjusted and a new balance is reached after this adjustment. When the viscosity changes, the scraper is changed, the speed is changed, the ink is added, and the solvent is added, the color of the ink film must change. Therefore, the operation should be started after the confirmation of the color sample.
Dongguan Beite packaging materials Co., Ltd. - located in Dongguan City, the world's manufacturing city, is a subsidiary of Beite packaging (China) Co., Ltd., with a plant area of 6000 square meters. It is a flexible packaging enterprise integrating R & D, production and sales. It has a complete set of domestic advanced production equipment, a scientific and humanized management system and a group of experienced technical personnel For backing, to provide customers with quality products and first-class service.
The company produces composite bags, roll film, fruit bags, aluminum foil bags, suction mouth bags, self-supporting bags, zipper bags, anti-static bags, special-shaped bags, etc., which are suitable for the internal and external packaging of food, daily chemicals, electronics, toys, medicine, cosmetics, industrial products and other industries.
We uphold the integrity of cooperation, good quality, good service business philosophy, won the industry's approval, products sold to all over the world; welcome friends from all walks of life to inquire, visit our factory to investigate guidance and business negotiations.