<abstract xmlns="http://www.w3.org/1999/xhtml"><p> According to lots of books, the pressure in offset printing affects the optical density and the quality of printouts. One of the quality parameters is a tone value increase. An advantage of our research method is obtaining printing effects for different pressures on one printout, thus meaning for identical printing conditions. We obtained the same printing conditions through using different amounts of underlay sheets fixed to the blanket cylinder, under a blanket. The pressure was increased from optimal settings - in accordance with the machine manufacturer’s recommendation. The test printouts were printed using Adast Dominant 515, on a coated and an uncoated paper. The optical density value was measured on the tone value scale from 10% to 100% stepping regularly by 10%. For this scale the tone value increase was computed. The research shows that for both types of paper the optical density and the tone value increase changes not very much above the optimal pressure recommended by the machine manufacturer. A difference in the optical density and in the tone value increase is bigger for coated paper than for uncoated paper. Changes in these two parameters are negligible in places where used form 0 to 4 underlay sheets and are quite significant in the place where 5 underlay sheets were.</p></abstract>

According to lots of books, the pressure in offset printing affects the optical density and the quality of printouts. One of the quality parameters is a tone value increase. An advantage of our research method is obtaining printing effects for different pressures on one printout, thus meaning for identical printing conditions. We obtained the same printing conditions through using different amounts of underlay sheets fixed to the blanket cylinder, under a blanket. The pressure was increased from optimal settings - in accordance with the machine manufacturer’s recommendation. The test printouts were printed using Adast Dominant 515, on a coated and an uncoated paper. The optical density value was measured on the tone value scale from 10% to 100% stepping regularly by 10%. For this scale the tone value increase was computed. The research shows that for both types of paper the optical density and the tone value increase changes not very much above the optimal pressure recommended by the machine manufacturer. A difference in the optical density and in the tone value increase is bigger for coated paper than for uncoated paper. Changes in these two parameters are negligible in places where used form 0 to 4 underlay sheets and are quite significant in the place where 5 underlay sheets were.

The Change of Printouts' Quality Depending on Pressure of a Blanket Cylinder Against an Impression Cylinder and a Plate Cylinder in Offset Machine

Faculty of Production Engineering, Institute of Mechanics and Printing, Warsaw University of Technology, ul. Konwiktorska 2, 00-217 Warsaw, Poland

Acta Mechanica et Automatica

This article is distributed under the terms of the Creative Commons Attribution Non-Commercial License, which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

According to lots of books, the pressure in offset printing affects the optical density and the quality of printouts. One of the quality parameters is a tone...

The Change of Printouts' Quality Depending on Pressure of a Blanket Cylinder Against an Impression Cylinder and a Plate Cylinder in Offset Machine

Publié en ligne: 02 juil. 2014

Pages: 9 - 15

DOI: https://doi.org/10.2478/ama-2014-0002

Mots clés
Optical Density, Tone Value Increase, Contact Between Cylinders

© Bialystok University of Technology

This article is distributed under the terms of the Creative Commons Attribution Non-Commercial License, which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

The Change of Printouts' Quality Depending on Pressure of a Blanket Cylinder Against an Impression Cylinder and a Plate Cylinder in Offset Machine

Publié en ligne: 02 juil. 2014

Pages: 9 - 15

DOI: https://doi.org/10.2478/ama-2014-0002

Mots clésOptical Density, Tone Value Increase, Contact Between Cylinders

© Bialystok University of Technology

This article is distributed under the terms of the Creative Commons Attribution Non-Commercial License, which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

Mots clés
Optical Density, Tone Value Increase, Contact Between Cylinders