Measurement of the dielectric properties of paper

摘要: Unlike dc resistivities of non-impact printing papers that are routinely measured, their dielectric properties seldom considered. The resistivity alone does not predict the behavior paper very well when passes through a transfer nip. If electric field changes with time, all anisotropic frequency-dependent electrical should be We present new method for measurement in principal directions sheet. In frequency range 20 Hz-1 MHz, permittivity e' and loss factor or conductivity σ can measured. Measurements on coated uncoated commercial showed some interesting characteristics. spite low moisture content ofcoated paper, its constant increased increasing relative humidity at same rate as copy paper. measured machine direction (MD) was much higher than what thickness (ZD). For difference between MD ZD constants small. both types greater direction. Dielectric more z-direction. Differences were attributed to anisotropy