SC Print Quality Influenced by Fiber Length, Fabric Structures and Machine Drainage Characteristics, 2001 Engineering / Finishing & Converting Conference

R. Danby

This paper presents details of an in-depth study of European and North American SC printing grades. It will show that the final print quality is influenced by headbox fiber length, forming fabric fiber support spans in relation to fiber length and also machine drainage forces and turbulence on each side of the sheet.

Using a unique computer print simulation technique developed by AstenJohnson Research, the study clearly shows that it is the very outside layer of the sheet which directly influences final print quality.

This study has been based on the analysis of stock samples taken from the headbox, commercial sheets made using that headbox stock and a detailed analysis of the forming fabric used on each side to form the sheet on that particular paper machine.

Each sheet was split (lamination technique), first in half, and further into a total of 14 parts. The uniformity of the outside 12.5% of each surface was then be examined and compared to the remainder.

The image of the outside 25% was used for the computer print simulation process.