On the development of modern printing technology

On the development of modern printing technology

the times are developing and the society is progressing. With the rapid development of social informatization and economic globalization, printing technology is also undergoing great changes. While traditional printing continues to develop, electronic printing has also risen. Printing technology, process, service mode, method and object have changed

first, digital technology has brought great changes to prepress.

the progress of printing technology in the 1990s is characterized by the application of digital and networking technology, which has evolved from desktop publishing system (DTP) with monochrome processing of text and graphics to electronic color publishing system (CEPs) with color graphics and text processing, and completed the transition from analog to digital processing of graphics and text information processing technology. Since the electronic color publishing system (CEPs) came into being, it has basically replaced the traditional processes of photography, color separation, production and plate making in terms of publishing, packaging, trademarks, advertisements, etc., and plays the leading role in the field of color creative design and reproduction in the prepress field. Great changes have also taken place in image information sources; Originally, analog information was obtained through original or physical photography, but now digital information is input into the computer through digital photography or scanning for processing and utilization. In the traditional simulation process, if you want to make some modifications to the original graphics and texts or change the hue, you must start from the camera or even the original information source, and completely rework from scratch, which is time-consuming, consumable, and the effect is not necessarily ideal

however, for the electronic processing technology of digital image and text information, not only the geometric shape of the image and text can be changed, the color and tone level of the image can also be greatly changed, but also the editing, obscuration and assembly can be achieved seamlessly. This is undoubtedly a new breakthrough for the traditional analog technology, and the addition form has also developed from amplitude modulation to frequency modulation, and even both can be used on the same picture to improve the addition effect

in the past, under normal circumstances, from photography to proofing, no matter how fast, it can be counted every day. Now digital proofing can not exceed one hour, and it is faster to implement "soft proofing" with computer display. And the sample can be modified at any time through man-machine dialogue. Because CEPS system and color image digital information processing technology have the above excellent functions and significant timeliness, it is natural that CEPS system has quickly become a popular pet in the market and has been popularized and applied. In the industry, the term "pre - press" instead of "plate making" has been understood and accepted, but in recent years, the term "pre - media" has appeared, temporarily translated as cross media pre-processing, which means that image digital information is not only "pre-processing" for "printing", but also "pre-processing" for "cross media" preparation, that is to say, in the future, pre - press will lead not only to printing, but also to "cross media". The future is bright and promising

second, digital printing and computer direct plate making

digital printing and computer direct plate making technology are popular printing technologies in the late 1990s, but from the situation of our country, they are still in the embryonic stage for the time being, with limited application, but there is a trend in their future development

digital printing refers to the printing technology that directly outputs the digital information processed by the computer to paper or other substrates, so it does not need to go through plate making, and the output information is random and variable. Unlike the traditional plate printing, the same print can only be printed from the same plate, thus developing the concept and practice of personalized printing and variable information printing, which is fast, personalized and flexible, This is the characteristic of digital printing. Moreover, the digital printing information can also be stored for printing at any time or in different places through the network when necessary

another type of digital printing equipment is based on the traditional offset press and combined with the digital direct plate making technology on the machine, which belongs to the type of plate printing. Such development has become a trend. Digital printing can be printed on demand in terms of quantity, time, distance and content according to customers' needs. This is not only a remedy for traditional printing, but also the continuous penetration and expansion of modern information processing and transmission technology into the printing field, and computer direct plate making (CTP) technology is also one of them

at present, in general, because the price of special plates and plate making equipment is not low, and the quality and quantity are still to be observed, many potential users believe that in the near future, the quality of plates and equipment will be better, and the price will also decline. Therefore, they hold a wait-and-see attitude, but they affirm that the average profit margin will rise and develop in the future

III. high speed, automation and high quality of traditional printing

high speed, automation and high quality are the common development direction of traditional printing equipment (whether lithography, gravure or flexo). Take the separate lithography machine as an example, the speed has increased from 1 50000 prints increased to 1 80000 or even 20000 seals; The drum lithography machine has increased from 50000 - 60000 revolutions per hour to 100000 revolutions. The speed of gravure printing, flexo printing and other printing locomotives has also increased. With the increase of the speed, the automation of the printing machine is also improving. Automatic loading and unloading of printing plates, automatic registration, preset and automatic adjustment of ink volume, automatic adjustment of wetting system, automatic cleaning of rollers and cots, automatic monitoring of double sheets, automatic tracking and monitoring of printing sheet quality, etc., have become common devices on printing machines. In terms of web printing machines, they also include automatic adjustment of tension, web feeding, paper receiving, folding and cutting. Only a high degree of automation can give full play to the efficiency of high-speed. On the other hand, due to the substantial increase of the speed, the interference of the cylinder gap to the balanced operation of the machine is more prominent. Therefore, the blanket cylinder and the printing plate cylinder are developing in the seamless direction, and the sleeve blanket and sleeve printing plate came into being. The pointer instability of electronic tensile testing machine refers to the change of group transmission from coaxial transmission to independent motor unit drive. These technical improvements are conducive to ensuring the quality of printing products at high speed

IV. main evolution in several major printing processes

in the four major printing processes of flat, convex (flexible), concave and hole, in addition to the above important improvements on plate making and printing equipment, there are also the following main evolution

1. Lithography: no horizontal printing, the main principle is to use the oil repellency of silicone resin as the ink resistant layer of lithography plate, and carry out lithography without the protection of wetting liquid. After trial development, the flat printing has been increasingly accepted by the market in the past 10 years. Horizontal printing has become an important process of high-quality lithography

2. Relief printing has basically been replaced by flexographic printing. The metal plates originally used for embossing, except for copper plates used for rolling concave convex graphics and texts or bronzing, have been replaced by polymer plates, and the process has also become a flexographic printing process, that is, from long ink path to short ink path, and the ink is evenly transferred by the roller

3. In the past 20 years, gravure printing has lagged behind due to the rise of flexible printing. The share of gravure printing in the overall printing market has not increased, but has been affected by the development of flexible printing (mainly in the field of packaging printing). The main reason is that the cost of preparing gravure plate cylinder is high, which is related to the increase of less batch printing in the market, forming a contradiction between supply and demand economic interests. However, it cannot be considered that the development of gravure printing technology is too slow. From the aspect of printing equipment, its improvement is also noteworthy in terms of print quality, efficiency and automation. For example, the high-speed multi-color gravure rotary die-cutting production line is one of them. Therefore, gravure printing still has its advantages in the printing of fine, high-grade and large quantities of cigarette packaging

4. In recent years, silk printing has developed rapidly. In view of the above characteristics, silk printing has become the main body of hole printing. Due to the small investment, the development of silk printing has become one of the important printing processes. The development of silk printing is wide and fast, sometimes giving people the illusion that it is difficult to be elegant, but in fact, silk printing is not so. Silk screen printing in the printing of electronic circuit boards or electronic components, more and more high-precision technology is expected to bring huge demand for vanadium to the vanadium industry, especially the highly integrated circuit board electronic components, which are very strict with the dust-free requirements of the printing equipment process and production site, and the investment is not trivial. This is another typical example of high-tech promoting printing, which in turn serves high-tech. The two promote each other, so silk printing has developed into one of the important printing processes

v. special printing technology came into being.

with the development of printing technology and the different needs of people's lives, the application scope of printing methods and printing is expanding, which has gone beyond the four major printing categories, and has produced many new printing methods with new characteristics and kinetic energy, such as inkjet printing, three-dimensional Shaanxi printing, electrostatic printing, holographic printing, pad printing, etc. These new printing methods are playing an increasingly important role in social life and production. With the development of science and technology, there will be more special printing methods

source: Joint Journal of Tianjin Vocational Colleges