There are several different methods for determining the roughness of paper and board. When paper is intended for letterpress printing, it is desirable to have a measure of the depth of the pits in the paper surface when under the pressures encountered during printing, to indicate the ink film thickness required for a satisfactory result.
BS 6563 describes a method for determining the roughness of paper and board under printing pressures, by use of the Parker Print-surf air-leak apparatus. Air-leak methods provide convenient means of testing paper roughness, but they are known to be subject to errors caused by the flow of air through the paper.
BS 6563 is applicable to coated and uncoated papers and paperboards which are intended to be printed by contacting printing processes.
BS 6563 on the roughness of paper and board is useful for:
Surface roughness is a significant factor in determining the printability of papers and paperboards. By measuring roughness under conditions approximating letterpress, litho and gravure printing processes this method yields information relevant to the performance of the product during printing.
BS 6563 provides you with a parker print-surf method to measure the roughness of paper and paperboard under conditions intended to simulate the nip pressures and backing substrates found in printing processes.
BS 6563 guides you with the preparation of test pieces. The results of the test are expressed directly as an average value of roughness which in many cases correlates better with printability than other comparable methods. BS 6563 guidelines help to ensure efficient printability of papers and paperboards.