Application of Screen Printing Technology on Ceramic Seepage Tiles (I)

Ceramic infiltrating tile is a new product developed in the 1990s. It combines the high strength, wear resistance, corrosion resistance of natural granite and the rich decorative effect of natural marble and color glazed tiles. Its rich and colorful colors and exquisite The pattern is mainly achieved through the screen printing process, and most of the current use of direct screen printing method, fine print patterns, high production efficiency, the process flow is roughly as follows:

The bottom plate making (positive picture) One screen printing plate making (direct photosensitive plate making method) The bucket printing plate one enamel prepares a proofing One brick Surface treatment One screen printing

From the above process flow, we can see that the difference between the tile screen printing and the general screen printing process is the process of enamel preparation, brick processing and so on. In the production process, if the process is not properly controlled, the quality of the seepage bricks will have a greater impact. The following focuses on some issues that should be taken into account when applying the screen printing process on architectural ceramics.

Influence of the distance between screen and brick on the quality of printing

In screen printing, the spacing between the tile and the screen directly affects the accuracy of the printed pattern. With the movement of the scraper, the screen will undergo a certain deformation, the pattern printed on the brick and the pattern on the screen will not be exactly the same, so theoretically analyzed, the smaller the distance between the brick and the screen, the pattern on the brick The higher the precision, as shown in Figure 1. Fig. 1a is a schematic diagram of deformation of a screen image when the distance between the tile and the screen is large, and Fig. 1b is a schematic diagram of the deformation of the screen image when the distance between the tile and the screen is small. In the actual production control of building ceramic seepage tiles, the spacing can neither be too large nor too small.

In the screen printing process, when the squeegee scrapes through the screen, it is required that the screen must leave the surface of the tile before the stencil adheres to the mesh. Otherwise, the edge of the image may be blurred due to the infiltration of the enamel into the body. Moreover, if the speed of the wire mesh leaving the brick blank is too slow, as the moisture in the glaze is volatilized, the seed glaze easily adheres to the wire mesh, and the seed glaze particles continuously gather, resulting in blockage of the wire mesh mesh. The spacing between the tile and the screen has a direct effect on the speed at which the screen leaves the surface of the blank. When the distance is small, during the movement of the squeegee, the deformation of the screen is less, the upward tension generated by the screen is reduced, and the speed of the screen leaving the surface of the brick is decreased. If the viscosity of the stencil is large, it may be Attached to the mesh, the screen cannot leave the surface of the brick, causing serious printing defects.

Of course, the spacing between the screen and the brick cannot be too large. Excessive spacing not only reduces the accuracy of the pattern, but also imposes higher requirements on the strength of the screen material. Moreover, the speed of the screen leaving the surface of the brick is accelerated, and the amount of the penetrant impregnated into the body is relatively reduced, resulting in a light and blurred pattern. Therefore, the distance between the screen and the brick is an important parameter, and it should be comprehensively considered according to the requirements of the pattern precision and the performance of the enamel. (to be continued)