Ink viscosity of the six big influence to the quality of gravure, attached to the treatment

Version of gravure printing ink viscosity product easy cause fog, misting problems, as well as to the color, transfer rate and the influence of color saturation, small make up finishing the following six major problems and treatment measures. Fog, a question: in the plastic gravure printing plate roller of ink printing surface with a layer of hazy often, transfer to the printing substrate often present a flake or lines dirty version, this is the dirty version, version is also called the fog. Causes of fouling version problem in addition to ink formula itself, the pressure of scraping blade and contact Angle and the quality of the plate, also related to the viscosity of printing ink. Such as printing ink viscosity is too high, ink viscosity is bigger, the plate of high-speed movement, the ink will produce a great impact through the scraping blade. The scraping blade is hard to make the graphic part of the ink scrape off smoothly, version of the resulting. If the ink pigment in the ink system of distribution is not uniform, or failed to ink in the resin pigment particles is a good package, so between the pigment particles will gather again. The larger particles in the formation of pigment groups easily in the printed form linear or strip cutter line. In general, the lower the viscosity of ink printing, the less prone to dirty version, so pay special attention to in the process of actual printing printing ink half of the degree of change, adjust the printing viscosity, high barrier composite packaging printing quality. Second, high-speed printing ink problem: when the intaglio printing speed is more than 20 m/min, if the gravure ink used domestic chlorinated polyethylene molecular weight distribution is very wide in PVC resin, result in printing ink viscosity is too low, may bring & other; Misting & throughout; The problem. The reasons are printing ink viscosity is too low. In cohesion of the ink, printing ink to printing, composite membrane transfer, low molecular weight of resin is easy to be isolated, in the blank section of the printed matter can see small & other; Ink & throughout; 。 Address & other; Misting & throughout; To solve the problem, you can from the following two aspects: one is to use a narrow molecular weight distribution of chlorinated polypropylene resin. Second, according to the printing conditions, increasing viscosity of printing ink. Three, for color, transfer rate and the influence of color saturation, such as: gravure of network under the background of the ink is relying on the gravure gravure printing ink transferred to the printing substrate, relatively, the volume of printing dot is the basic fixed. With the increase of printing ink viscosity, ink viscosity has been increased, the more ink also from network transfer out, so the color of the printing quality and the higher concentration, saturation, but there is a certain limit. When ink viscosity rise constantly reaches a certain level, ink transfer rate is achieved synchronization, if ink viscosity also continues to rise, ink viscosity is more and more strong, hard ink began into very small branches, branches of printing ink is less and less, ink transfer rate began to decline gradually. The color of the print concentration began to fall. Ink manufacturer suggested gravure printing ink viscosity in 13 ~ 22 seconds, this is just the experience value, in the actual printing process, to achieve good printing effect. Be careful to choose printing viscosity. Four, on the influence of printing speed: domestic existing gravure printing ( Including JinKouJi and MTK) From 30 m/min - printing speed 300 m/min. In the 80 - general printing machine printing speed 200米/分钟。 In the actual printing, must undertake choosing according to the printing speed of printer. When printing speed increase, its printing viscosity value will drop. Of course the most suitable viscosity printing. Also influenced by other factors: 1, even if is the same printing speed, due to differences in ink formula design, the viscosity of printing will also be different. So in the actual printing process, must according to the printing effect to adjust. 2, the influence of seasonal temperature: the same printing ink in the summer and winter there are differences in viscosity, ink production enterprises have also been in order to reduce the influence of temperature on the ink viscosity. 3, according to the actual condition of the printing plate roller select the most appropriate printing ink viscosity. Five, the impact on the crystal gloss printing: the lower the gravure printing ink viscosity ( Add more solvent to oil ink) In the printing ink resin and pigment content reduces, transfer ink to printing substrate is not easy to form a smooth ink layer after drying. And appear white phenomenon, as a direct result of print lack luster. So in order to get excellent gloss, must ensure that the printing ink has proper resin and pigment content. Six, electrostatic problem: under normal circumstances, the printing ink itself in the OPP antistatic ability is limited, than polyamide type table printing ink and ink more prone to electrostatic polyurethane system. For the OPP in printing ink, the higher the viscosity of the printing ink is less prone to electrostatic problem, under the condition of normal temperature of the printing ink viscosity in more than 16 seconds ( 3 # zahn cup) Electrostatic generally do not occur, If printing viscosity below 16 seconds / 3 # cup beard, stripes, such as edge exclusion malfunction is likely to happen. If printing ink viscosity has been in 15 seconds / 3 # cup, we suggest that do not adopt the method of improve the viscosity of printing ink as far as possible, because of printing ink viscosity will not only increased transfer printing cost will also bring difficulty, prone to dirty version printing failures, etc. According to the specific conditions of static electricity, use other ways to eliminate static electricity, for example, can be diluted by changing the solvent ratio. Add 5% isopropyl alcohol ( Polar solvent, good conductivity) Or discretion to add a small amount of antistatic agent can static elimination.