PURPOSE: To prevent the sharpness of an image from being deteriorated even under high humidity environment, by using an insulating recording medium where a dielectric layer having spherical spacer particles and binder is coated on the surface of a base film as a rugged layer.
CONSTITUTION: The insulating recording medium 3, at the side on which an electrode stylus of a recording electrode 1 contacts, is provided with a rugged layer 32 where a bead spacer member 33 is deposited on the base film 31 with a binder 34. The rugged layer 32 allows the electrode stylus to have a prescribed interval (e.g., 10μm) to the film 31. Thus, discharge is caused from the electrode stylus applied with a voltage to the film 31. A 16μm polyester film is used as the film 31, an inorganic substance is used as the spacer member 33, and a thermoplastic resin close to an inorganic substance or a thermosetting organic resin is used as the binder 34. It is required that the surface resistivity of the base film is ≥1012(Ω/cm2) when the sharpness of permissible range is ≥0.4.
AMAYA MIKIO
NAKAJIMA JIYUNZOU
| JPS5313421A | 1978-02-07 |