METHOD AND DEVICE FOR MEASURING PAPER DENSITY AND MOISTURE CONTENT

摘要

A resonant frequency (f1) and peak resonance level (P1) of a microwave resonator in a first state in which a sample is not present and a resonant frequency (f2) and peak resonance level (P2) of the microwave resonator in a second state in which the sample is present are measured, and a resonant frequency shift amount (∆f = f1 - f2) and peak level change amount (∆P = P1 - P2) are determined. A moisture content (WT) is determined using a calibration curve indicating the relationship between ∆P and the moisture content (WT). Using the following relationship between ∆f, WT, and BD, a paper density at absolute dryness (BD) is determined from ∆f and the WT value determined using the calibration curve:∆f = A ∙ BD + B ∙ WT (A and B are constants)