Abstract: The invention concerns a procedure for measuring the coating quantities contained in coating layers deposited on both sides of paper, cardboard or equivalent material in the case in which both coating layers contain the same component emitting characteristic radiation. In the case most commonly encountered, both coating layers consist of the same coating material. In the procedure two functionally mutually independent radiation source/detector pairs are used, between which the coated paper or equivalent is placed. Separately each radiation source/detector pair effects excitation of fluorescent radiation in both coating layers under measurement and the total intensity of the excited radiation present at the detector is measured. If the base weight of the paper or equivalent is known, the coating rates are calculable from the results of measurement obtained. The base weight is most advantageously measured before the coating step with the aid of a separate source of radiation and a transmission detector.

Abstract: The invention concerns a procedure for measurement of the material quantities in coating layers applied upon a base material, by utilizing x-ray radiation. The procedure is particularly suited for use in a paper or cardboard manufacturing process wherein onto a material web in continuous motion are applied by steps one or several coating courses. The radiation source and detector are both placed on one side of the moving web, and the procedure is based on measurement of the fluorescence radiation excited by the primary x-ray radiation obtained from the radiation source in the material underlying the coating layer that is to be measured. The primary and secondary radiation both are thereby compelled to pass through the coating layer under measurement before the arrival of the fluorescence radiation at the detector.