1. High temperature resistance
Web pre-printing processing technology is to first carry out face paper printing, in the pre-printing printing machine is used to put forward and receive, the printed product still maintains the form of roll, and will be used as a face paper for processing corrugated cardboard. After that, the printed product is directly loaded into the corrugated paper production line, and then combined with the lining paper and corrugated paper to form corrugated cardboard.
In the process of processing into corrugated cardboard, the printing process is only one step in the processing, and the printed product can only be regarded as a semi-finished product, and it must enter the next process for further processing. In the process of corrugated cardboard production, in order for the adhesive in the corrugated cardboard to dry thoroughly, it must be dried at high temperatures. At present, the drying temperature of domestic tile wire is basically above 160 °C, and the drying temperature of some high-speed tile wire is even more than 200 °C. In this process, it is required that the ink color of the pre-printed pattern cannot be changed. Therefore, pre-printed inks must have better resistance to high temperatures.
2. Friction resistance
Pre-printing is just a processing process, and the printed product also needs to be tile. In the secondary processing process on the tile line, it is inevitable that the tissue paper will rub against the equipment, and the printed pattern must not be worn or even rubbed off. Therefore, the pre-printing technology also puts forward new requirements for the friction resistance of the ink.
Before the ink is blended, an important step is to analyze the original. When analyzing the color draft, it is mainly to analyze the color on the color manuscript and the ink used, and the principle that should generally be followed is: the three primary colors are the basic colors of all ink colors, no matter how complex the color, no matter how it changes, it can not exceed the range of the three primary colors. When analyzing the color draft, it is necessary to figure out as much as possible whether the color draft is mainly printed on the screen or in the field. If the screen printing is the mainstay, it is necessary to focus on the consistency of the background color when mixing the ink; If it is mainly printed on the spot, you can focus on the consistency of the surface color when blending; If you have both, then you have to take into account both the base color and the complexion when mixing the ink.
After the color manuscript is analyzed, the color of the ink used should be analyzed, that is, for any kind of ink, it is necessary to be good at seeing the color components. For example, for yellow ink, it is necessary to be good at identifying whether it has a red or blue color (or a green color); For magenta ink, be good at identifying whether it has a yellow or blue (or violet) phase; For green ink, it is necessary to be good at distinguishing whether it has a red or green (or yellowish color).
Suppose the green ink is mixed with green ink and yellow ink, if the green ink has a red phase, or the yellow ink has a red phase, the green obtained by the line of mixing will not be darkened, because this is actually equivalent to adding magenta ink to the green ink and yellow ink, and even if this part of the magenta is very small, it is necessary to mix the same amount of cyan and yellow into black (yellow + green + magenta = black) according to the principle of pigment subtractive color, and add a small amount of black to the green, the color will of course be darkened, and the brightness and saturation will be greatly reduced.