Sharp Kabushiki Kaisha Corporation

Kanto Denka Kogyo Co., Ltd.

Masatomo Hayashi

Hidehiko Iinuma

Natsuki Matsuura

Tadashi Iwamatsu

Hiroshi Maeda

Takanori Kamoto

Osamu Wada

Nobuyuki Yoshioka

Taiji Iizuka

Kenkichi Hara

Masao Obata

Yasuji Yabe

Yukinari Oguma

Masaki Arima

Nobuhiro Seki

A resin coated carrier is provided that can stably charge a toner having added thereto an external additive having a large particle size over a long period of time and can prevent blocking of a developer. The resin coated carrier satisfies the following formula (1):log()&#x3e;2&#x2003;&#x2003;(1)in which Ma is a weight average molecular weight of a silicone resin having the minimum weight average molecular weight, contained in a resin coating layer, and Mb is a weight average molecular weight of a silicone resin having the maximum weight average molecular weight, and

Resin coated carrier, two-component developer, developing device and image forming apparatus

This invention provides an Mg-based ferrite having a high dielectric breakdown voltage and a saturation magnetization suitable for electrophotographic development, a carrier containing the ferrite, and an electrophotographic developer containing the carrier. The Mg-based ferrite material of this invention comprises Li, Na, K, Rb, Cs, Ca, Sr, Ba, Y, La, Ti, Zr, Hf, V, Nb, Ta, Al, Ga, Si, Ge, P, Sb, Bi or a combination thereof. The Mg-based ferrite material has a saturation magnetization of 30 to 80 emu/g, and a dielectric breakdown voltage of 1.5 to 5.0 kV. The Mg-based ferrite material can realize high image quality, and be in compliance with environmental regulations.

Mg-based ferrite, an electrophotographic development carrier containing the ferrite, and developer containing the carrier

This invention provides an Mg-based ferrite carrier composed of an environment-friendly material meeting environmental regulations, and an electrophotographic developer comprising the carrier. The carrier and the developer of this invention realize high image quality and improved gradation properties. This invention also provides a method for producing the Mg-based ferrite material having a saturation magnetization of from 30 to 80 emu/g and a dielectric breakdown voltage of from 1.0 to 5.0 kV, and having the composition of the formula (1). The above properties are obtained by controlling conditions of sintering and heating treatments. CaaMgbFecOd (1) wherein a, b, and c satisfy 0.10 b/(b+c/2) 0.85 and 0 R(Ca) 0.10; R(Ca) is expressed as R(Ca)=a&#x2dc;Fw(CaO)/(a&#x2dc;Fw(CaO)+b&#x2dc;Fw(MgO)+(c/2)&#x2dc;Fw(Fc2O3)) (Fw(A): formula weight of A j; and d is determined by oxidation numbers of Ca, Mg and Fe.

Mg-based ferrite, an electrophotographic development carrier containing the ferrite, and a developer containing the carrier

A display apparatus of a simple matrix type displays an intermediate tone on a liquid panel by a data thinning-out system. As a modulated alternating inverted signal for determining a polarity of a driving voltage is applied to each pixel of the liquid panel, employed is a signal whose phase is inverted by 180.degree. every tone representing cycle which is a predetermined period of a plurality of frames, and it is structured such that a polarity of the driving voltage to be applied to each pixel is changed according to polarity of the modulated alternating inverted signal. Therefore, a positive polarity portion and a negative polarity portion of an effective voltage to be applied to a pixel in an arbitrary tone representing cycle are completely canceled by a negative polarity portion and a positive polarity portion of the driving voltage to be applied to the pixel in a tone representing cycle adjacent to said arbitrary tone representing cycle respectively. As a result, each of mean values of effective voltages applied to respective pixels in the two adjacent tone representing cycles becomes zero, so that no direct voltage is applied to the liquid crystal panel.

Display apparatus and method of driving display panel

A display circuit for a simple matrix type liquid crystal display apparatus which is multiduty. The picture element data of one line portion is sequentially output through the segment driver into one electrode contacting the liquid crystal. The scanning pulses are sequentially output through the command driver into the other electrode contacting the liquid crystal. The driving circuit further reverses the polarities of the outputs at a constant period with an alternating signal, so as to drive the respective liquid crystal.

Driving circuit for liquid crystal display apparatus

Growing community of inventors

Shibukawa, Japan

Masatomo Hayashi