Units of paper quantity Units of paper quantity Various measures of paper quantity have been and are in use. Although there are no S.I. units such as quires and bales, there are ISO and DIN standards for the ream. Expressions used here include U.S. Customary units. A quire of paper is a measure of paper quantity. The usual meaning is 25 sheets of the same size and quality: of a ream of 500 sheets. Quires of 25 sheets are often used for machine-made paper, while quires of 24 sheets are often used for handmade or specialised paper of 480-sheet reams. (As an old UK
Paper and ink testing Paper sheets are cut to a size of 10 cm x 10 cm, then the sheets are massed individually. The mean of the masses is used to calculate the mass of the paper per square meter, and the standard deviation is determined from all samples. If the mass is higher than specified, it is a loss for the publisher. Defines the thickness of the paper.Consistency of caliper throughout the paper web is an important consideration.An abrupt increase or decrease in caliper can affect the extent to which the printing plate or blanket contacts the paper and transfers a complete printed