312. What are the contents of the identification plate quality?
A: Identify the quality of the printing plate:
(1) Inspection of the quality of plate appearance;
(2) Inspection of layout specifications;
(3) color identification;
(4) Inspection of graphic content;
(5) Inspection of network quality;
(6) Inspection of signal strips (test strips).

313. What is the appearance quality of the plate?
A: The appearance quality of the printing plate refers to the external performance state of the printing plate. Generally, it is checked visually. The basic requirements for the appearance quality of printing plates are: layout and back cleaning, flat layout, uniform glue removal, no breakage, no creases, no scratches, no dirt and ink spots, etc.

314. What are the contents of the plate layout check?
A: The layout specification inspection includes: layout size, graphic location, mouth size, fold relationship, notch size, and mouth size. It can be checked according to the layout specifications required by the printing process sheet and the printing machine specifications. The quality standard of the layout specification is: the printing plate size is accurate, the error is less than 0.5mm, the dimensional error between the chromatic printing plates is less than 0.1mm, and the image is no sun drying phenomenon.

315. Why do you want to identify colors?
A: Each plate represents a certain color. The color is used to distinguish different colors of the plate, such as yellow, magenta, cyan, and black. The structure of the images on these plates, such as tone levels, dot area size and distribution, network line angles, and text, lines, etc., are all disassembled and distributed with the color characteristics of the manuscript, the tone structure, etc., and the layout is well-organized. The color of the image is generally black (after ink extraction). Therefore, the printing plate on the machine must be identified by color, so that the printing color and the required printing plate are completely consistent, and the product is not obsolete due to color errors.

316. What are the methods of color identification?
A: The traditional method of color identification is generally the dot angle identification method and the layout of the text shade depth contrast identification method. In addition, the color of the film currently used by the photo-composing machine is provided with a color mark, which can be identified according to the color mark on the printing plate.

317. What are the requirements for graphic content inspection?
Answer: The basic quality requirements for the inspection of printed text and graphic content: The text is correct, no words, characters, characters, or characters are missing; the lines should be intact, and the line thickness should meet the design requirements; the picture and the text should be consistent. The correct direction; multi-color version of the sun set, the color version is complete, no lack of color or sunburn phenomenon; proper rules line complete and complete, no incomplete phenomenon.

318. What are the contents of the network quality check?
A: The quality of the printing plate outlets mainly refers to the fullness of the printing plate's Internet sites, the level of edge smoothness, sharpness, and reproducibility. Detection can use the magnifying glass (5 ~ 50 times), based on the original quality standards on the quality of the plate on the qualitative and quantitative detection. The printing plate quality that satisfies the printing requirements should be: full, complete, smooth, no damage, no scratches, no hollow, no points, no defects, less burrs, narrow edges and no distortion of the dots, dot gain , shrinking within the prescribed range.

319. What are the contents of the signal strip (test strip) or copying scale inspection?
Answer: The signal strip (test strip) or printing scale is a reflection signal to control the printing quality, check the printing quality, and master the printing plate image condition. Through its ability to check out the reduction or increase of the printing plate's Internet point due to insufficient exposure, excess, or other causes during the printing, to check the printing degree and quality of the printing plate, this is a method of scientifically checking the printing plate. .

320. What is the printing plate resistance?
A: The printing resistance of a printing plate is a descriptive indicator of the stability and service life of the printing plate, and it is the comprehensive ability of the plate printing and textual basis to resist pulling, abrasion and corrosion. According to the structure of the printing plate, the theoretical fastness can be determined from the physicochemical properties of the graphic base layer and the blank intermediate layer, the molecular structure, and the physical state of the printing plate surface. The printing plate resistance force is the maximum printing capacity displayed within the limit of the allowable product quality after the printing plate overcomes various physical and chemical effects in the printing process. The printing plate resistance to printing force is affected by the plate base material, the roughening treatment method, and the basic performance of the graphic and text, and is closely related to the plate making technology and printing conditions. Different printing plates have different resistance to printing force. The positive-printed PS plate that has not been baked has a resistance force of 80,000 impressions or more.

What is the 321. printing plate resistance force detection method?
A: The printing plate resistance can be detected by actual printing inspection and laboratory instrument testing. Printing inspection: printing directly on the machine, the limit print quality that meets the printing quality requirements is the printing force of the printing plate. Laboratory instrument testing: Application of special friction tester, tensile tester and other instruments to simulate printing status, indirect evaluation of data by measuring the number of friction of the printing plate, the adhesion of the graphic and text, and the degree of swelling and erosion of the solvent. The printing plate is resistant to printing force.

322. How does the printing machine work?
A: The plate-making machine is a contact exposure imaging device used for making printing plates. It uses pressure (including atmospheric pressure and mechanical pressure) to make the original plate and the photosensitive plate fit tightly so that the photo on the original plate can be accurately made through photochemical reaction. Ground on the photographic plate.

---From "Printing Technology"