Printing

Embossing is a special printing process that does not use ink in the range of plate printing. In the printed matter printed on graphic, according to its graphic made bumps and two plates, and then pressed with a flat press, so that the surface of the printed image is shaped like a relief, resulting in a unique artistic effect. Therefore, it is also called "rolling bumps." This method is similar to "arching flowers."

The printing process of bump printing is as follows: The production of the embossing plate is embossed.

First, the production of bump printing plate

First of all, to distinguish between the primary and secondary levels of the drawings, we must use subject performance as the theme, use the depth of the hierarchy, reach a certain depth, and then consider the secondary level. The main body of the highlight should be higher in elevation. The printing plate is first made into a gravure, which is performed by a carving process, and may be a woodcut version, a copper engraving, a steel engraving, or an etching plate; secondly, the representation of the figure and the line is determined, and the main body and the general level are coordinated, and the layout is deep and shallow. In order to coordinate, the outline of a picture should be from shallow to deep and have a certain slope. The engraving drawing is based on the perspective principle and near-deep shallow expression. After finishing the outline carving, the whole picture is polished and polished. Run.

The engraved gravure is glued in the center of the metal bottom plate of the flattening press and the printing plate is leveled to prevent unbalanced pressure, false pressure or walking, and the yellow plate paper is adhered to the platen. , To correct the pressure, the parts of the contour level more, according to different shades, with the yellow paper press the size of the printed surface cut into pieces of paper paste to form the trapezoidal punch with the same gravure, then the details of the trapezoidal punch is not The gravure is the same, a layer of gypsum slurry is laid on the trapezoidal punch, and the gypsum slurry is mixed with the fine gypsum powder mixed with the glue, and the consistency is appropriate. A thin paper is used to cover the gypsum slurry, and the gypsum will dry when it is not dry. Convex pressure test, in order to prevent plaster from sticking, you can brush a layer of kerosene on the gravure. When the pressure is used to gently shake the machine, the speed should be slow at the beginning so as to prevent the gypsum layer from spreading quickly, and the gravure and the relief plate do not coincide with each other. After the plaster has been hardened and set, it can be imprinted at normal speed. If the pattern that is pressed for the first time does not meet the quality requirements, the gypsum layer needs to be repaired, and when the plaster is not yet hardened, excess plaster on the non-embossed surface is scraped off with a knife.

Second, embossed version of the imprint

When printing, the printed matter is placed between the gravure and the relief, and under a greater pressure, the uneven pattern can be rolled out. If the paper is damaged due to excessive pressure or undulations during the embossing process, grind it evenly on the surface of the plaster. Always clean the embossed surface in the embossing to prevent dirt from pressing into the damaged surface. The nature of the printing paper is relatively hard. When the quality of the product is high, hot pressing may be used. That is, a resistance wire may be added in the middle of the metal base plate, and the current may be passed through during operation so that the printing plate can be heated and the high-quality product can be pressed.