On the quality control of cigarette label gravure

Talking about the quality control of cigarette label gravure printing

in order to meet the high-quality, long-term and large-scale packaging needs of Yunnan cigarette trademarks, many Yunnan printing enterprises have invested in gravure printing equipment to print cigarette trademarks in the early 1990s, forming an upsurge in the history of Yunnan printing. In recent years, we have experienced a process from unknown to familiar with gravure printing technology and quality control. Here, we only take some process improvement projects and quality control procedures of the company in recent years as examples to discuss the quality control of cigarette label gravure printing

(-) reasonable process design and technical improvement are the premise of quality control

inking and flying ink are the most common quality problems in gravure printing at the beginning, resulting in a high scrap rate. After analysis, the main reasons for the ink drawing phenomenon are the material problems of the ink knife itself; The flatness of the printing plate surface; Impurities in the ink, such as coarse particles and foreign matters, lift up the part of the tool. For the most common third reason, we are in the ink cycle 5. In a horizontal environment without impact and vibration; Filtering is added to the system, which realizes the filtering before ink application and filtering during circulation, and effectively controls the inking phenomenon. To solve the problem of flying ink, we should start from prepress. First of all, the layout design should not be too full, and the best effect is when it accounts for 75-85% of the maximum printing width; The second is to improve the chamfering accuracy of both ends of the plate roller, reduce the concentricity deviation, and also reduce the phenomenon of ink flying; The two ends of the third printing plate are equipped with ink blocking hard films, which can also prevent ink splashing

the Honghe Cigarette label printed by our company has strict requirements on hue, and the depth of the printing plate directly affects the hue index. In order to make sure that even some people know that there are technologies such as 3D printing to ensure that the hue index is qualified, the printing plate is required to have a certain depth. The deeper plates have poor smoothness. Although the number of lines and the angle of engraving needle have been adjusted many times, there has been no substantive breakthrough in smoothness. Last year, our company put into use a high shear emulsifying machine, and the ink insisted on emulsifying first and then on the machine. During the emulsification process, the ink particles are fully ground, and the ink after grinding is fine, uniform and smooth. After being used on the machine, the evenness is significantly improved, and the ink drawing phenomenon is also significantly reduced. Different kinds of colors need to be added to the ink in the process of hue adjustment. Due to insufficient mixing, ink transfer is easy to occur during printing, which is commonly known as white strip pulling. The high shear emulsifying machine solves this problem in the process of color ink blending

(II) formulating acceptance standards for key auxiliary materials is one of the keys to quality control

surface scratch, moisture degree and dust degree of paper; Viscosity of raw ink, range of hue L, a, b values, printability; Water content, dryness and residual odor of the solvent; Printing plate samples are listed as the most basic auxiliary material inspection items of our company

(III) strengthening process supervision and improving statistical records are the intermediate links of quality control

if the reference printing resistance index specified by the printing plate is 1million turns, the process control department will focus on monitoring the printing plates that are still printing beyond the specified number by issuing a preventive action notice, which will not only control the potential quality influencing factors, but also save the production cost. The company also implements the system that the quality management department regularly evaluates the supplier's ability through the statistical data monitored in the process, and selects the supplier in combination with the periodic statistical qualification rate of auxiliary materials

(IV) quality awareness is the foundation of quality control

our company has a leading group that attaches great importance to quality, and has formulated the quality policy of "people-oriented, advanced technology oriented, advanced management methods as control means, and ensuring quality first". A series of documents such as gravure process system documents, process discipline documents, process quality control system documents and quality reward and punishment regulations have been formulated and implemented, which not only make the company's employees tighten the quality strings from top to bottom, but also make the quality workers realize that "there is a law for degradation and disappearance in seawater within a few days to hundreds of days after abandonment"

in a word, employees' quality awareness, skill quality, reasonable printing process design, equipment performance, auxiliary material performance, etc. are related to gravure printing quality. With the development of gravure trademark printing industry, gravure quality control will still be a long-term topic, and we still need to do a lot. Only by constantly exploring and summarizing, can we better grasp the gravure quality, so that the impact testing machine has the characteristics of stable transmission, low noise, high speed accuracy, wide speed regulation range, long service life and so on; Auto parts testing machine adopts microcomputer to automatically control the experimental process, and the quality really becomes a powerful guarantee for enterprise competition