Abstract: The present invention provides a long-life carrier for developing an electrostatic latent image to be used in such field of applications as electrostatic photography and electrostatic recording, a developer of an electrostatic latent image utilizing said carrier, a method for forming an image and an image forming apparatus by using said developer. By use of the foregoing qualities, a high-quality image can be obtained.

Abstract: A positive TCR thermistor device has excellent electrical contact between a heat generator and heat radiating blocks and high heat transfer efficiency therebetween. The positive TCR thermistor includes a heat generator having a positive temperature coefficient of resistance and heat radiating blocks supplying electric current to the heat generator and heating a heated medium by receiving heat generated by the heat generator. The heat generator is provided with a metallic paste electrode at a contact surface which is in contact with the heat radiating blocks and oil having flowability is disposed between the metallic paste electrode of the heat generator and the heat radiating blocks.

Abstract: An ignitor includes a first transistor, a transformer, an ignition member, and a switching control member. The first transistor is activated in accordance with supply from a DC power supply to perform switching. The transformer has a primary winding through which a switching current flows via the first transistor, a secondary winding for generating high voltage when the switching current flows through the first winding, and a tertiary winding for generating a control output for controlling the switching of the first transistor in accordance with the high voltage generated in the secondary winding. The ignition member ignites a target object using the high voltage generated in the secondary winding of the transformer. The switching control member prolongs the ON time for the switching of the first transistor in accordance with a decrease in at least one of the ambient temperature and the power supply voltage.

Abstract: A positive-temperature-coefficient thermistor heating device including of a PTC element, a first electrode formed on its surface, a heat radiating means having heat radiating fins and a second electrode, and conductive particles contained in the first electrode and electrically conductive with the second electrode, and, also, a process for production of a positive-temperature-coefficient thermistor heating device including the steps of printing an electrode material paste containing conductive particles on the surface of a PTC element, heating this to bake it on and form a first electrode having a rough surface, and bringing the first electrode and the second electrode of the heat radiating means into contact by the conductive particles.