The most popular overprint method for color printi

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A prepress detection overprint method for color printing

a method for printing a printing pattern, comprising the following steps:

a printing pattern forming process for forming a printing pattern such as a resist made of a resist component on an etching film formed on a substrate

and the subsequent thinning process, thinning the resist in the thickness direction by dry etching such as plasma ashing or wet etching such as development processing before etching using the printed pattern as a mask

as well as the etching process, the etched film is etched by Jinan assay Vickers hardness tester using the thinned printed pattern as a mask

a prepress detection overprint method for color printing, which belongs to packaging printing technology. The prepress detection overprint method and prepress detection pre correction system can directly detect the overprint error of the unprinted belt material before printing, and accurately correct the error in advance, ensuring that the overprint error of the belt material after printing is minimized and automatically returns to zero, improving the printing quality and avoiding the waste of printing materials, It is the most ideal color overprint method for various high-speed color printing equipment and is committed to creating a more transparent and environmentally friendly packaging color overprint system

selection of plate plane shape before plate making

December 31, 2006 13:58 source: 0 comments from Yitian economic and trade friends entered the forum

plate quality is the premise of printing quality. Without a good quality plate, it is impossible to print high-quality works. In the process flow of plate making, it is important to clean the upper glue plate drying, exposure, development and other processes, such as selecting, stretching and direct stripping fixtures), but the plate shape is also one of the factors affecting the printing quality. This paper deals with the selection of plate plane shape before plate making


version shape is the plane shape of the box. To make a version selection box, you usually determine the size of the box according to the net content of the draft plus the width of the ink area, and then consider what material is used for the box bar and how large the material is. The box shape is mostly rectangular, and only a few rare shapes are selected when encountering a special substrate. For example: Handkerchief printing is square; The advertisement printed on the finished sunny umbrella adopts triangle or isosceles trapezoid due to the influence of the umbrella bone; Large color printing selects hexagon to strengthen the bearing capacity of the frame and prevent inward deformation; The concave bucket bottom and basin bottom are round. In fact, the special plate shape is not only suitable for the special printing surface, but also practical for the ordinary plane in the aspects of tension force, tension uniformity, printing resolution, inking volume, etc., especially in the production of fine lines and the use of high mesh silk for step color printing. The following three aspects are described from the plate stress analysis, printing experiment and practical application

I. stress analysis of the plate plane

the silk screen printing plate is an elastic version. Stretching and scraping both deform the silk and require the silk to be restored to its original state. The frame bears the restoring force transmitted by the silk. This restoring force can be regarded as the sum of the tensile force, the scraping force and the shear force generated by the friction between the scraper and the page during operation. Since the motion force is instantaneous, the scraping force can be controlled manually, and the frame force can be regarded as the tension under static conditions. From the 90 tension point of view, within the limits of silk elasticity, the greater the tension, the tighter the version, the more uniform the tension, and the better the quality of the version. However, the tension will not be 100% transferred to the plate, and the loss of tension is mainly due to frame deformation and wire fatigue. In response to this contradiction, high-strength wire and trapezoidal cross-section frame came into being, which can improve the quality of the plate. However, if the frame and strip materials are infinitely increased, the weight will be increased and the actual operation will be affected. The deformation of the frame is proportional to its length. The longer the frame is, the greater the deformation is, and the greater the tension loss is. Therefore, the deformation of the frame varies with the shape of the frame. The following is the stress analysis of circular, hexagonal, square and rectangular frames under 90 tension (see Figure 1)

it can be seen from Figure 1 that on the circular frame, each action point is subject to the wire restoring force in both vertical and horizontal directions, and the resultant force of the restoring force points to the center of the circle to achieve balance, so there is no inward deformation. The force on the intersection point on the hexagonal frame remains unchanged, and the length of the six sides is relatively short. Under the action of the vertical resultant force, the deformation is minimized. The square frame has the same side length, which is the smallest deformation in the rectangular frame, and the tension uniformity after deformation is the best. The smaller the ratio of the short side to the long side of the rectangular frame, the greater the deformation, which has the greatest impact on the tension uniformity of the whole version

II. Printing experiment


1 Use 2cm 2cm metal square tube to bend two semicircular frames with a diameter of 40cm on the bending machine, and then weld them together. Hexagonal, square and rectangular frames are made from the same materials

2. After the frame is made, it shall be sanded and glued twice, and 300 mesh wires shall be selected and stretched on the same stretching machine, with a tension of about 8kg. Let the stretched version stand horizontally for 3 ~ 4 days

3. The blank plate is scraped and printed with 4 pieces of real land

4. Use 60 lines to make 1-9 eye positive adjustment pictures, make printing plates with the same content on the four frames, and scrape and print two clearest tone maps on 3mm white glass with each plate. Compare the printed samples of various shapes. Experimental results: the ink and evenness of the rectangular plate are slightly poor, point deformation, incomplete, and there is a phenomenon of step narrowing. The quality of samples of other versions is close to the same

III. practical application of plate shape

the circular and hexagonal frames are tight, with uniform tension and good printing effect. However, in practical application, the circular frame should be bent by a circular bending machine, with complex process. The effective printing area is an inner rectangle, which wastes materials; Although the hexagonal frame is welded with straight edges, it has many welding points and difficult to control the angle. There are also problems with the circular frame, which is lack of practicality. Only the square version has the advantages of the above version, and the processing technology is the same as that of the rectangular version, so it is better to choose a square with a side length of 1:1 or a rectangle with a side length ratio close to 1:1

when the author was just engaged in printing, he used 13 large, medium and small plates with different shapes to make a batch of large-scale maps. In order to be faithful to the original and meet the mathematical accuracy in the figure, the zigzag free crisscross square centimeters and hairy contour lines are printed to clearly reflect the five types of rivers and beaches Х It is the first time that the government has taken part in the reform and opening-up. T Lei said that he would like to take part in the reform and opening-up of China's economy for seven days, except for the first time that the government would take part in the reform and opening-up of China's economy, and the second time that the government would take part in the reform and opening-up of China's economy? 0cm 80cm, 90cm 90cm, 100cm 120cm, three groups of 12 plates are recycled. During typesetting, multiple contents shall be put together as much as possible, or one kind of content shall be arranged several times to form a layout. The patterns that cannot be spliced by overprint shall be made into small drawings by large version. It is worth it if they can succeed. Due to the change of plate shape, the monthly printing task in the later stage is as many as 80 plates and 3000 sheets of paper, with a success rate of 100%. The printing accuracy of the high-efficiency extraction metallurgical technology for iron bearing resources and poor and difficult iron ores is 2 times, and the negative error is zero. The contents of the drawings are clear, the lines are smooth, and the characters are full. The drawings submitted to the Provincial Bureau and ministerial level authorities for acceptance meet the specifications and standards. Later, the author used a square plate to make a four fan screen with step tone flowers and birds. The effect was acceptable, which also laid a foundation for large-scale color silk printing in the future

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