The reasons and countermeasures of pile rubber
We are a big printing company in Shenzhen China . We offer all book publications, hardcover book printing, papercover book printing, hardcover notebook, sprial book printing, saddle stiching book printing, booklet printing,packaging box, calendars, all kinds of PVC, product brochures, notes, Children's book, stickers, all kinds of special paper color printing products, game cardand so on.
For more information please visit
http://www.joyful-printing.com. ENG only
http://www.joyful-printing.net
http://www.joyful-printing.org
email: info@joyful-printing.net
“Heap Eraser” is one of the common faults in offset printing. When the blanket is just stacked, the print is unclear, and the dots are pasted; when accumulated to a certain extent, the color shift and the dirty plate phenomenon are caused, and the wear of the printing plate is aggravated. There are many factors that cause “stacking rubber”, and the processing methods are different. The following are the reasons for each.
1. The surface coating of the paper is not firmly adhered and the paper powder is excessive. The coating on the surface of the paper is unevenly coated or insufficiently smeared. Under strong light, the surface of the paper is rough or there are many paddles. For the "stacking rubber" failure caused by this situation, in addition to adding appropriate amount of additives, it is also possible to appropriately reduce the printing pressure without affecting the quality of the printed product, and slow down the speed during the printing process to reduce the peeling of the paper. solve. If necessary, you can first pass the white material through the empty roller to remove some paper and paper scraps from the paper surface. If the product allows, the light paddle will be better.
2. One of the main reasons for the pile rubber is that the fibers on the surface of the paper are stuck to the paper powder due to the high viscosity of the ink, so that it is piled up on the blanket. Solution: You can put appropriate amount of additives or viscosity reducer in the ink to reduce the viscosity of the ink. The amount of additives should be controlled to avoid affecting the drying performance and gloss of the ink.
3. The surface of the blanket is crystallized and too smooth. Through experimental comparison, the smooth surface of the blanket has a much greater adsorption force on the paper wool impurities than the rough blanket. Solution: Thoroughly clean the blanket to restore the surface of the fluff, or choose a blanket with a slightly rougher surface to get better results.
4. The ink is excessively emulsified. After the ink is emulsified, the pigment will separate from the suspended state, and will remain on the blanket causing "stacking" or staying on the plate to cause "stacking". It can be seen that the ink on the ink roller is sticky and granulated, and the ink is dull. It can be solved by cleaning the ink roller, appropriately reducing the viscosity of the ink, and re-adjusting and controlling the ink balance.
5. The ink is drying too fast. When the ink layer of the unit ink roller is thin, after a period of printing, the ink roller generates heat, so that the drying speed of the ink is too fast. Since the ink has the strongest viscosity when it is dry, the transfer rate is lowered, and a pull-down phenomenon occurs, resulting in a "stacking rubber" phenomenon. It can be solved by: a. reducing the temperature of the workshop to keep the humidity at about 65%; b. adding an appropriate amount of viscosity reducing agent or dry agent to the ink.
6. The color sequence is not arranged properly. The ink color of the back color group is greater than that of the front color group, and the back color group pulls down the ink of the front color group to cause accumulation, and severely causes cross color. The method can be solved by adjusting the color sequence and adjusting the viscosity of the ink so that the viscosity of the back color group ink is slightly smaller than the viscosity of the ink of the front color group.