Study on the factors affecting the gravure printing is accurate andWith other printing way (as offset, and network printing,) as, intaglio printing products also requirements all single version must has precision, and accurate of overprint location, if overprint location occurred has deviated from, on will appeared rules deviation and overprint errors, caused printing image of tones and level occurred changes, makes image blurred, text of overprint appeared drag tail, and leak white, phenomenon, and to Hou road process (as hot printing, and pressure convex, and die cut, and pressure marks,) of processing increased difficulty, effect printing products of quality, caused not due of cost increased. Below the author on factors affecting Web gravure printing printing accurate, to talk about my views. A paper roll tension 1. paper roll tension on the tension of paper reel paper paper roll change of tightness of the affected paper tension, instability likely to cause tension, making printing and reference sometimes you lead, sometimes lag behind, thereby affecting the printing graphics and text alignment. Although almost all gravure press with paper tension adjustment device before printing, but if the paper roll is too loose, beyond the scope of device adjustments, would have fluctuated in the tension roller in the printing process, resulting in misregister. Once we use the gold card paper of cigarette factory in Jinan, "Amber King" when the cigarette, found printed product printing is good or bad, the upper and lower deviation. Because it is a six-color printing, all printing units are occupied, so initially we thought that the situation was caused by various printing printing pressure is inconsistent, but the pressure has been carefully adjusted, the effect is not obvious. Later, a print worker in transport of inks, solvent, found the Unwinder balloon Web loose on the shaft to the inner core going sideways, leading to tension roll moves up and down too fast and hit the ground, and reached the top position, causing misregister. Change after a new paper roll, set of problems are solved.
2. how judge paper volume of elastic author think, first removed reel paper paper volume Shang of outside packaging Kraft, show internal printing with paper, then carefully observation paper volume sides volume have align not align, if paper side compared align, description this paper volume elastic degree uniform consistent, can Shang machine printing; if paper side in out turn, rugged, is description paper volume a part had pine or had tight, should not be for printing. According to we years of using experience, imports reel paper as United States of "weishiweike", and Finland of "double a,", and Canada of "Butterfly", white paper jam, Japan of "three ocean policy" coated paper and the domestic of Ningbo Chinese paper of Whiteboard paper, and Kim Dong-paper of coated paper its paper volume of elastic degree more uniform consistent, in printing process in the General not appeared overprint no of problem.
II-for paper rolls, 1. effect of paper for printing the current gravure line unwinding adopts paper static paper paper and dynamics in two ways. Whether it is dynamic or static paper tray, paper roll moment unwinding machine paper in the presence of tension rollers are at rest. Tension roll moves up and down rapidly, making paper tension but little changed, print graphic misregister phenomena to occur. In fact, under normal circumstances, this phenomenon of misregister by overprinting the master Console adjustments will automatically return to the normal printing position. But if the new paper roll with the paper being printed is not produced by the same manufacturers, misregister problems are likely to arise. Once we print Harbin cigarette factory "Harbin" cigarette when, due to supplier's reasons, we need to swap with another brand of paper-"Red Tower" Web. In our printing "weishiweike" paper, after receiving a new paper roll, overprint problems found through overprinting recover console, so we can only adjust pressure to re-registration. After analysis, we believe that is due to these two sources of quantitative, thickness and change the printing pressure, thus affecting the registration.
2. connectors on the printing of the paper within a paper roll effect paper within a paper roll joints will also affect overprinting. This is because the two paper overlap each other at the joint, front and back are tape, becoming thicker and when a joint paper to the printing unit pressure roller when printing pressure changes cause misregister. Paper roll joints more paper tension changes, the more the number of printing pressure change more the number, set, the more unstable, resulting in paper waste. Roll paper paper roll each connector is the equivalent for cigarette paper, makes the tension changes affect overprinting. Before the printed roll up, carefully inspect the packaging for any marked paper joints, or after you open the packaging paper check for paper connector marked line and ready to work in a timely manner. Recommended gravure paper manufacturers do not use volume connectors reels of paper, so as to avoid unnecessary waste.
of printing pressure in all three ways of printing, gravure printing pressure imposed by most. Printing pressure uniformity and size affects paper tension changes, which affect overprinting.
1. Printing pressure of uniform consistent sex according to years of practice, author think, for printing color number less of products (4 color within), printing pressure of uniform sex on overprint of effect not too big, as long as printing pressure reached printing products of requirements can; but for printing color number for 4~6 color even more Shi, on must on each printing unit of pressure rubber roll for adjustment, makes each unit of pressure rubber roll ends keep flat, and consistent, before and after unit of pressure phase consistent, or unit and unit Zhijian will appeared "Out of paper", so that the paper is too loose, or paper wrapped around the gravure cylinder, scraping knife blade for damage. Addition, in daily in the, to keep pressure printing rubber roll surface clean, because some non-normal downtime (as broken paper, and suddenly downtime,) will makes ink slot and small ink spill ink, pressure printing rubber roll also inevitable to will stick Shang some, ink in rubber roll Shang dry Hou formed firm ink skin, makes rubber roll of local perimeter increases, to makes whole rubber roll of uniform sex occurred changes, while also will accelerated pressure printing rubber roll aging.
2. printing printing pressure pressure size key, under normal circumstances, normal shutdown can be used to verify the size of printing pressure. If under normal outage per unit pressure roller can automatically lift, description printing pressure is just the right size. Of course, at this time for certain colors (such as gold, red bottom) may appear printed false, that is, "issued on" phenomenon, and therefore can be printed according to the actual situation, while maintaining uniform pressure increased on the basis of a unit of pressure.
four plates of the thickness of the shaft head gravure cylinder into the shaft drum and shaft-less version of the drum.
of shaft-less version, every change needs a version of axis to support. Axis after many times of use, heads will wear thinner, outer metal sleeve will bounce, drum rotates to form eccentric motion effects and overprint. For the axis cylinder, due to plate fees higher, printing factory will repeatedly removing the plate cylinder using, in the course of this (more than 8 million cycles), shaft becomes finer and finer, of the above results. If you want to continue using this version of the drum, recommends that the reduced metal sleeve inside diameter dimension of the shaft, as a gravure printing plate cylinders with shafts of higher production costs, and metal processing prices are relatively cheaper.
plate fastening when plug in version, if too loose on the intaglio fastening plug, will make the printing cylinder embossing rollers under the action of axial movement occurs, there is a graphic horizontal misregister of failure. So in the version before the working end, product registration, be sure to carefully check all gravure printing unit-solid plug is loose. Fastening plug internal bearing wear will also have an impact on printing. If worn, there will be a metal shaft movement, intaglio jumping fault. In order to prevent wear of the bearing, at the time of each version, internal bearing fastening plug must be applied a certain amount of butter.
six photoelectric scanning head key parts of the photoelectric scanning head is the detection of intaglio printing, it scans the signal directly to the console, so the signal stability for printing plays an important role. The photoelectric scanning head following a brief description of the use and maintenance. Photoelectric scanning head closely related to the detection angle and the printed colors. In general situation Xia, like red, and black, and gold, and green, more deep of color, because signal strong, so scan head can open detection; and for yellow (transparent yellow, and in the yellow, and pale yellow), and shallow Brown and the gold and silver paper jam Shang printing of white,, due to signal weaker, then scan head must rotating must of angle for detection, and also to gently regulation scan head Shang of fine-tuning spin twist, until main control Taiwan displayed of signal stable weizhi. When scheduling, producing gravure gravure printing process, generally want to choose darker colors as a base for overprinting color, machine overprints on the upside to this is to facilitate production. In order to prevent the scan head provide a wrong signal, on a day-to-day basis to keep the photoelectric scanning head clean, staff to regularly check on the scanning head, head crystal clear to prevent dust, wool, paper scraps and ink particles and other debris enter the photocells Interior, jamming signal.