On the application of inkjet technology in the digital printing industry
physically speaking, printing is a process of copying or reproducing graphic information
with the development of computer technology, automatic control technology and material technology, a new type of ball screw is produced. It is a graphic reproduction technology that relies on the rotation friction of the ball. It is called inkjet printing technology. It is also a graphic reproduction technology. It may play a role in the printing industry and find its own place
I. the development direction and current situation of the printing industry
digital printing and digital plate making are the two main directions of the development of the printing industry today. Printing includes gravure printing, embossing printing, flexible plate printing and silk printing. The printing equipment is constantly updated to make printing faster and more square. According to the difference of the maximum experimental force (loading capacity) it can test, the load sensor is also divided into 50N and 5kn, which is convenient, more economical and more in line with the needs of the development of commodity economy and society. Its common feature is to use computing as a pioneer machine technology and new material technology to innovate the original plate making and printing process. The disadvantage is that different printing methods need different plates and different plate making equipment. Digital printing and digital plate making have become a rapidly developing trend. Various technologies are looking for their own development space here, which is a very obvious strategic feature facing the current printing industry
II. Classification of digital printing
at present, digital printing can be divided into three categories:
1. Computer direct plate making - it uses a computer to control an optical system to directly arrange images on the plate for printing, eliminating the original laser Phototypesetter
2. Computer direct printing - that is, the printed plates are arranged on the printing machine in advance, and plate making is carried out through a plate making system controlled by the computer. After plate making, direct printing is carried out. The printing machine itself is a plate making machine, which combines the two into one
3. Digital printing - no carrier is needed. Direct digital printing is controlled by computer. The intermediate process of printing is not needed. The graphic and graphic information is directly transferred to the recipient, and the speed is slow
at present, in terms of plates, digital printing includes three parts: plate making equipment, plates and inks. The most important one is the plate. Basically, plates can be divided into the following categories:
1. Silver salt photosensitive plate - this kind of plate is based on aluminum plate, with a silver salt photosensitive layer on the surface, which is then scanned and exposed by computer-controlled laser, and then printed directly. The advantages are high precision, high sensitivity, fast exposure speed and good imaging quality; Disadvantages: the price is expensive, and there is certain environmental pollution
2. Silver salt composite PS plate refers to the pre coated photosensitive plate. It is coated with a layer of photosensitive material on the PC plate, scanned by the computer, and then exposed to form a picture and text. This layer of picture and text is exposed with ultraviolet light to remove the photosensitive material of the upper layer of PS
3. Photosensitive resin plate - the photosensitive material used is a mixture of halide and polymer, which has photosensitivity. It is characterized by high sensitivity. It can be scanned with a general infrared laser machine, with a resolution of more than 2000dpi. It can be scanned with computer control for direct plate making. But its stability is poor
4. Thermal plate - thermal plate is not sensitive to light, but to heat. The laser line used is infrared laser line. Because it adopts heat sensitivity, it improves the working efficiency without chemical treatment, and has no pollution to the environment. According to different materials and photosensitive properties, thermosensitive plates can be divided into two categories: the first category is thermochemical reactivity, which means that the scanned part of the surface coating generates heat for thermochemical reaction under infrared laser scanning, and the original non light ink becomes light ink, while other parts are light water. This kind of plate can be printed directly. There are several types of this plate, but its basic principle is the same. It has the characteristics of high sensitivity. The laser is more than 800~900 nm. A few years ago, silver salt plate was considered to be the most mature, but now thermal plate is the development trend. The second kind is called laser "stone burning". This kind of plate is generally composed of three layers (some of which are four layers). The most superficial layer is the silica gel layer, which is neither mucous membrane nor water. The second is the layer layer, the third is the ink absorption layer, and below it is the plate base. First, the pictures and texts are prepared by the computer, and then the laser is controlled by the computer to scan this kind of board. The laser power is large, and the sensitivity is about one joule per square centimeter. The engraved pictures and texts are where the printing is stained with ink, and other places are not stained with ink. This kind of board can be waterless offset printed after laser "burning stone". This kind of heat sensitive plate has high resolution, up to 5000dpi. Because it is waterless offset printing, it will not point spread. It is a kind of plate with great development prospects
digital printing, through laser scanning image to form a preprint: one is toner preprint, the other is electronic ink preprint, that is, the preprint part absorbs toner or electronic ink, which is the most used material in digital printing
At present, there are more than 60 kinds of plate making equipment in the world, including external roller, internal roller and flat plate type. According to different plates, there are several milliwatts to several watts of equipmentat present, the development of digital printing abroad is very fast, accounting for a large proportion in European and American countries. It is just emerging in China, and some manufacturers are exploring it. They plan to engage in digital plate making and digital printing based on the PS version with low price, mature technology and all localization. It is worth discussing whether inkjet printing can also take PS version as the main printing means. At present, the annual output of PS version in the world is more than 200 million, and that in China is 40million, which is a very large market. (end)
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