Causes Of Printing Tape Impression Formation For Desktop Flower Box

Causes of printing tape impression formation for Desktop Flower Box

When using the original collage printing version of the PS version, it often leaves some tape and the original edge of the printing plate, the direct reason is caused by the use of the original collage method to produce the printing version of the positive image, if the use of the whole original will not appear this fault phenomenon.

So why will the use of collage original printing produce tape marks  First of all, it is certain that the lack of exposure is the main reason for its production. Because although the Mosaic tape is very thin and transparent, in fact, it will absorb and block a part of the light through, resulting in local underexposure, so the sensitive layer corresponding to the blank part of the printing plate can not be thoroughly developed during development, and it is easy to appear impressions. But why is it not the overall uniform tape impression, but the edge of the tape is more obvious than the inside 

First, when exposed, the optical phenomenon is different when the light passes through the center and edge of the tape, because the central part of the tape theoretically belongs to a uniform medium, while the edge of the tape, especially the critical part of the tape edge, belongs to an uneven medium, which will produce different degrees of light scattering, refraction and diffraction. At the same time, there will be a ring of air layer around the edge of the patchwork tape, which produces optical path difference and causes optical interference phenomenon. This will cause the edge of the tape to be even less exposed.

Second, in the process of use and placement, dust and other dirt are attached to the side of the tape, resulting in additional light blocking and light absorption phenomenon, further causing local underexposure. In actual work, especially when the environmental conditions are poor, it is often seen that the edge of the tape is obviously with a dark edge, and the original version of such a tape collage must be printed.

Third, in the development process, there will be a certain "critical effect". Although plate development is mostly dynamic development, from the macro point of view should not exist this phenomenon, but from the micro analysis there is still the possibility of this impact, although not as obvious as film development, but can not be ignored.

The fourth is the visual existence of the "Mach van der effect", which further aggravates the phenomenon of printing tape. The edge of the tape impression on the plate layout after development is visually more obvious than the center, and this effect is small but insurmountable.