Detection Methods Black Mark Detection Sensors are positioned facing the backside of the paper to detect paper loading from the optical reflectance of the paper. (The black mark reflectance rate must be 10% or lower, and the white reflectance rate must be 70% or higher.) In order to accurately detect black marks, use paper having black marks printed at the positions indicated for each black mark of the paper specifications. Gap Detection Transmission-type sensors are positioned along the paper path to detect paper loading from differences in the light transmission rates between the backing paper and labels.
(The light transmission rate of the backing label must be 40% or more and that of the label must be 23% or less.) Light transmission rate: Light transmission rate (%) = Light transmission amount/Amount of irradiation light x 100 46