Abstract: It is provided a rewritable printing method and its printer in which a heat sensitive medium with a leuco type coating applied is used to rewrite the information repeatedly, printing can be performed in the same way as the conventional technique, and the medium easily as the transmission means of the information, thereby extremely contributing to the improvement of environmental issues relating to the use of paper.

Abstract: A body fluid leak sensing device adapted for correctly informing only a caretaker of a leak of body fluid. The sensing device is miniaturized so as to properly operate in any worn state. A liquid sensor applicable to the body fluid leak sensing device is disposable and highly sensitive to even a small amount of body fluid. A sensor (1) comprises a water absorber (11) formed of a porous material with a high electrical resistance and an insulating coating film (14) on which the ends (12a, 13a) of the electrodes (12, 13) are secured at its sides and spaced from each other in such a way that one end (11a) of the water absorber (11) is exposed. There are provided means for detecting leak of body fluid by measuring the resistance of the sensor (1) and means for informing according to the detection.