1. Paper â‘ There are tension rollers at the front and rear of the commercial rotary machine. The paper is transmitted between the printing units under tension, and the viscosity resistance of the ink is added. Therefore, the mechanical properties of the paper such as long fracture and folding resistance Degree, tear strength, etc. have higher requirements. The better the mechanical properties of the paper, the less likely it is to break the paper, which can save a lot of unnecessary waste. â‘¡Now the commodity news of some hypermarkets, real estate advertisements of advertising companies, etc. all require printed products with bright colors and high saturation. Correspondingly, the paper should have excellent printability: water resistance, oil resistance, abrasion resistance, folding resistance, high surface strength, suitable pH and water content. At present, more light-coated paper is used, and the performance of different manufacturers' products is different: for example, UPM paper imported from Switzerland has serious surface wrinkles after printing and drying, but the surface does not dust off much. Some domestic papers have serious powder loss and some have low smoothness. 2. Ink Commercial rotary presses are generally faster. For example, the speed of Heidelberg M-600 is 44000 folio / hour, which requires excellent performance of the ink. â‘ Drawability: The characteristics of the drawing, breaking, and rebounding of the ink layer during the splitting process. In the high-speed printing process, the drawing is too long, and the phenomenon of flying ink is often formed. At the same time, the rebound is weak and the dot expansion is obvious; the drawing is too short Therefore, the transfer of the ink is not real, so it is required that the ink is used with a moderate stringiness. â‘¡Heat resistance: the resistance of the ink on the surface of the printed product to discoloration under high temperature heating. If the printed layer is dried in an oven, the ink layer becomes discolored and the image is blurred, which means that the ink has poor heat resistance. In use, it is found that the ink with dark hue has better heat resistance, because the ink pigment particles with dark hue are uniform, fine and high in purity, and the heat resistance depends on the performance of the pigment. â‘¢Ink fineness should be less than 15μm, because rough ink will accelerate plate wear and reduce the gloss of the surface of the printed product, so for the pursuit of high-quality commercial rotation, of course, the smaller the fineness of the ink, the better. 3. Fountain solution The fountain solution of a commercial rotary offset press is different from the newspaper rotary printing and more different from the offset offset printing. It requires that the fountain solution be conducive to a stable water-ink balance, with less water on the ink, to ensure the concentration of the ink, and to reduce emulsification. Even if the machine is running for a long time, it can still ensure stable printing quality and the machine's rapid startup. In the continuous water delivery system, the proportion of imported water bucket liquid additive concentration is 2% to 3%, IPA (isopropyl alcohol) ratio is 6% to 8%, and the hardness of the solvent water used is 4 ° to 25 ° DH. The PH value is controlled at 4.9 ～ 5.2 (it can be adjusted slightly according to the hardness of water), the conductivity is 800 ～ 1200μs / cm; at the same time, the fountain solution should be used so that the ink roller does not leave calcium deposits, reducing the residual ink on the blanket And paper powder should be able to effectively prevent foam and microorganisms. When the PH value of fountain solution is too low. The fountain solution will chemically react with the desiccant in the ink. In general, the stronger the acidity of the fountain solution, the slower the ink will dry; the PH value is too high, often caused by the IPA value is too high, will make the ink film lose gloss, The surface of the printed matter looks dull and dull. 4. Use of blanket During the printing process, if it is found that the blanket has collapsed, it is necessary to replace the blanket in a serious situation in which the blanket reducing agent does not work. If it is replaced with a new blanket, it is best to change the upper and lower versions at the same time. New blanket. Because the blanket is subjected to periodic stress during the printing process, it gradually forms enamel on its surface, and its dot reducibility and rebound ability will be greatly reduced. If the old and new blankets are used on a unit at the same time, the pressure of the paper tape between the new and old blankets is different, and the reducibility of the dots can be imagined and not much better. However, after replacing the old blanket, it is placed for a period of time. Generally imported high-end air cushion blankets such as Heidelberg DAYGRAPHICAL, etc., the micro-pore resilience layer will restore the elasticity of the blanket under the action of air cushion molecules, which is often said " Sober. " After “waking upâ€, the old blanket can also be used. Therefore, the principle of exchanging blankets should adhere to the principle of "old to old, new to new". In this way, the pressure on the surface of the paper and the surface of the blanket are basically the same, so as to provide conditions for obtaining good dot reduction. Plastic Salad Container,Plastic Salad Trays,Salad Plastic Bowls,Plastic Salad Boxes EVER GREEN(ZHEJIANG)NEW MATERIAL CO., LTD / KUNSHAN GREENPACK CO.,LTD , https://www.jiaxingevergreen.com