Wet pick is thought to be caused by the presence of water used in lithography. The quantity of the wetting fluid, surface tension of the wetting fluid and the time interval between wetting and printing were tested to see if they affect the paper surface strength. Two rolls of web paper are pre-sampled from the RIT press room. One was found to exhibit the problem of wet pick while the other did not exhibit this defect. These papers were tested on the IGT Printability Tester in a manner similar to that predicted on press when a moisture film of 0.2 micrometer is applied with no delay between application of ink and water. This method can be used to predict the defect referred to as wet pick. Adding to the moisture film thickness results in an increased wet pick in both good and bad paper with a delay between dampening and inking of 0.3 and 0 . 6 seconds . This researcher hypothesized that for a wetting fluid, the factors that contribute to picking are the quantity, the evaporation rate, and the wetting characteristic.
Library of Congress Subject Headings
Paper--Printing properties; Paper coatings; Lithography
Department, Program, or Center
School of Print Media (CIAS)
Liu, Chung-Ni, "Laboratory investigation of the effect of the dampening solution on the loss of surface strength of coated paper" (1993). Thesis. Rochester Institute of Technology. Accessed from
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