Missing dots

from Wikipedia, the free encyclopedia

Missing dots is a term from printer language and means missing halftone dots . Under the microscope it can be seen that printed paper is by no means smooth, but rather has numerous bumps. In a 70 grid there are around 4900 cells on one cm² of the printing form , which should transfer the printing ink contained in them to the paper in a fraction of a second. Engraved gravure forms tend to have missing dots, as some cells do not transfer enough ink to the paper due to their shape. Based on the number of missing dots, experts assess the quality of the gravure products. This problem is countered with electrostatic printing aids, which are located on the impression roller . The tension field generated by the printing aid pulls the ink completely out of the cells of the gravure printing cylinder and transfers it to the printing material.

literature

  • Helmut Kipphan: Handbook of the print media . Springer, Heidelberg 2000, ISBN 3-540-66941-8 .
  • Dieter Liebau, Hugo Weschke: Polygraph specialist lexicon of the printing industry and communication technology . Polygraph, Frankfurt am Main 1997.
  • Bernd Ollech: Gravure, basics and process steps of modern gravure technology . Polygraph, Bielefeld 1999.
  • Hans-Jürgen Scheper: Examination knowledge printing technology . Verlag Beruf und Schule, Itzehoe 2005, ISBN 3-88013-623-8 .