Abstract: An object of the present invention is to reduce the hysteresis loss ratio of a capacitive pressure-sensitive sensor by forming elastic layers from two types of elastic materials (i.e., a certain elastic material and an additional specific elastic material) when the hysteresis loss ratio is high in the capacitive pressure-sensitive sensor including the elastic layers formed only of the certain elastic material. The capacitive pressure-sensitive sensor includes a first electrode, a first elastic layer, a second electrode, a second elastic layer, and a third electrode that are laminated in this order. The first elastic layer and the second elastic layer exhibit different stresses as measured during compression and decompression at a rate of 0.5 mm/minute at 23° C. when the capacitive hysteresis loss ratio is the maximum, and the stress difference is 3 kPa or more.

Abstract: The present invention provides a sensor that exhibits a small effect on a detection target during detection, a high detection sensitivity, a wide dynamic range for detection, and a small change after repeated detection, as well as a composition suitable for use in the sensor. The composition is a polyrotaxane composition containing two polyrotaxane cyclic molecules crosslinked with a crosslinking agent present between the molecules, wherein the polyrotaxane composition exhibits a hysteresis loss of 10% or less, an elongation at break of 200% or more, an initial Young's modulus of 5 MPa or less, and a relative dielectric constant of 8.0 or more. The sensor includes a film formed of the aforementioned polyrotaxane composition, and elastomer-made electrode layers disposed on both surfaces of the film.

Abstract: A transducer device includes a first dielectric layer, a first electrode layer and a second electrode layer that hold the first dielectric layer in a thickness direction, a second dielectric layer provided continuously from the first dielectric layer, a third electrode layer and a fourth electrode layer that hold the second dielectric layer in the thickness direction, and a controller. The controller calculates a command value of voltage to be applied to the first electrode layer and the second electrode layer and applies a voltage corresponding to the command value to the first electrode layer and the second electrode layer so that the first dielectric layer is deformed in the thickness direction. The controller measures a capacitance Cs of the second dielectric layer via the third electrode layer and the fourth electrode layer and calculates the command value in reference to the measured capacitance Cs.