Die-cutting is an important process in relation to the production quality and production efficiency in the process of card making. Since the card book has special requirements for the process in the die-cutting process, there are different factors in the production process that affect the quality of the book. Therefore, it is necessary to strictly follow the technical requirements of the die-cutting process in order to avoid quality problems.
Card Book's die-cutting process: Die-cutting or die-up version One sets up the pressure on the machine. A regular sponge strip is used to test the die-cut and adjust the quasi-pressure. The die-cut is officially die-cut. This is a relatively standard die-cutting process, but from the die-cut product, some products have burrs and paper dust. Traces of weakness, and individual bursts occur.
Card paper used
More special, some papers have long fibers, and generally do not have burrs and dust. There is also a fair amount of white paper or gray-white paper that is short in fiber, low in density, heavily powdered, and has more dust after die cutting. And laborious. In view of this situation, we should choose a good-quality die cutter or a special die with good steel properties. However, the accuracy and sharpness of general die cutters cannot fully meet the requirements. Some die cutters use a magnifying glass to observe the blade, and they find that there are many flaws. The blade is not straight and smooth, which is one of the reasons for paper dust and burrs. Some manufacturers' cutting knives are sharp on the surface, but they are poor in steel. The blade will be worn out in a short time. This will cause dust and burrs to appear at the die cuts and windows in the paper edge or inside pages. Good die cutters are not necessarily expensive, and you can compare different brands of die cutters, select the right brands, and fix them down for targeted use. A good die cutter or die can both reduce the friction between the knife and the paper, make the product smooth and dust free, and reduce the wear on the machine equipment.
After the die-cut version is on the machine, it is necessary to press on the attached bottom paper (back-knife paper) to determine the exact position of the slot line on the bottom stencil. However, due to improper operation or excessive pressure, the blade and the steel base plate collide with each other too much and directly hit the cutting edge of the die cutter. Continuous pressure after formal production is also a major cause of blade damage. If it is not detected or the die cutter is not replaced in time, it may cause paper dust and burrs to appear to varying degrees.
Therefore, after the die-cut version of the machine should be based on the card book page to see which need to cut through, where need indentation, debugging pressure must be light, the bottom mold paper can have clear marks. After sculpting, adjust it and adjust it to set a pressure value. Under the steel plate under the pad, test pressure after the knife edge of the waste paper or printed products easy to separate. Withdrawal of the pressure, to do a partial pad of the uncut part of the treatment, so that the layout of the die cutter pressure uniformity, and then gradually increase the pressure on the machine. The ideal pressure is that when the waste edge of each incision is just separated, the pressure of the machine is the minimum and the pressure is appropriate. Touch the cut edge smooth, lint. Easy to separate, and die cutter is not easy to wear. When the automatic die-cutting machine starts to adjust the pressure, the substrate material is used to make up and wear according to different positions, and then the pressure is locked and then die-cutting. This results in the molding of the die-cut product, and the production speed is fast and the efficiency is high.
The page graphics of the three-dimensional card book need to be die-cut and indented. Before the die-cutting, the bottom stencil must be engraved first. The groove line engraving on the bottom stencil directly affects the drawing effect of the three-dimensional figure. If the grooved lines are not uniform, straight, or nicked, or if the die cutters, indentation lines and the bottom groove lines cannot be accurately matched, and the knife line linings are not suitable, the indentation shift can be caused. Die cutting cannot be completely cut off. During die-cutting, the paper may be pultrusion-shifted before the die-cutting knife has cut through the edges or graphics. The thickness of the general underlay paper is less than or equal to the thickness of the die cut paper. Hand-sculpted slot lines impose higher requirements on the operator's proficiency, skills, and experience. A skilled operator should understand that the indentation effect will vary according to the arrangement direction of the indentation line and the direction of the paper fiber. The graphic die cut lines and the marks in the page of the three-dimensional card book are parallel to the book and are also vertical. . In the die-cutting, the lines parallel to the direction of the paper web tend to be weak and dry, and the lines that are perpendicular to the direction of the paper web are full and powerful. For die-cutting of graphics, smooth-cutting is easier to separate, and perpendicular to the cocoon, often filiform fibers appear. Therefore, when adjusting the underlay, the indentation line grooves in the ruled-line direction are preferably narrower. The edge of the die-cut product is clean and smooth, with strong lines and lines.
Improper selection and installation of rebound rubber strips is also one of the reasons that affect the quality of die-cutting, because the sponge strip should have enough hardness to compress the paper, let the die-cutting knife/frames cut the paper differently. Paper should use different hardness sponge tape, installation location and height must also be scientific. Standard material selection and installation is the fundamental way to improve the quality of die-cutting. Because the change of the three-dimensional card book pattern and the distance between the die cutting edges are irregular, some pitches are small, and the layout is irregular, which brings difficulties to the selection of the hardness and correct use of the sponge strip. The correct selection and installation are as follows .
1. Rebound sponge rubber hardness choice
(1) If the distance between the die cutters is <10mm, the hardness of the sponge strips should be about HS60; if> 10mm, it should be HS20 ~ HS35.
(2) If the distance between the die cutter and the steel wire is <10mm, the arched sponge rubber strip is used and the hardness is HS55; if >10mm, the sponge rubber with the hardness of HS35 is selected.
2. Rebound sponge tape installation
(1) The sponge strip should be at least 1-2mm away from the die cutter and cannot be installed close to the blade body. Otherwise, the sponge strip cannot expand in the direction of the blade body after being pressed, and can only expand in the other direction, resulting in pulling the paper on both sides. The die cutter also has to cut the paper in the future, and the paper has been broken by the sponge strip. This will cause the edges of the graphics to be not clean, or even deform or tear the paper so that the die-cut pages will not be even.
(2) Sponge tape should be about 1.5mm higher than the blade, depending on the hardness of the appropriate adjustments, in general, the softer sponge tape, the higher the height. The quantity, hardness, and height of the sponge strips on the entire die-cut plate should be evenly distributed in the corresponding positions. Sponge strips should also be arranged on both sides of the balance knife.