Sharp Kabushiki Kaisha Corporation

Fuji Electric Co., Ltd.

Kao Corporation

Mitsubishi Kasei Corporation

Mitsubhishi Kasei Corporation

Yahata Electric Works Ltd.

Hiroshi Kinashi

Yoshiharu Tsujimoto

Itaru Kawabata

Teruhiko Noguchi

Jitsuo Masuda

Yuhi Yui

Kunio Ohashi

Mitsuru Tokuyama

Mamoru Nozomi

Hideaki Hagihara

Ken Yamagishi

Tadashi Umehara

Junji Morimoto

Toshiya Asari

Yuji Okamoto

Masashi Hirai

Kozo Takahashi

Hiromu Sasaki

Kazuya Adachi

Masayoshi Nawa

Yoshihisa Miwa

Yoshiaki Imanaka

Katsushi Inoue

Hidenobu Yamane

Tatsuo Tanaka

Zitsuo Masuda

Koichi Irihara

Tadashi Akiyama

Shinya Gotoh

Tooru Nakata

Kunio Otsuki

Hiroyuki Kawataki

Shoshichi Kato

An electrophotographic photoreceptor comprising a cylindrical electrically conductive substrate having thereon at least a photoconductive layer, the conductive substrate having a marking portion in which the light reflectance of the surface of the conductor substrate has been changed by a laser light treatment, a method for producing the photoreceptor, and an image correcting method using the photoreceptor.

Electrophotographic photoreceptor and method for producing the

Image correcting method using an electrophotographic photoreceptor

The present invention provides a process control stabilizing system including a cleaning device for the corona wires which allows the process control to be carried out optimally based on exact information which is obtained by certain sensors while a discharge from the main charger unit is kept uniform. The system is constructed so that an electrode cleaner is activated before the detection of the surface potential and/or the detection of the optical density, and in addition, the cleaning operation will be operated until the detection result falls within a predetermined range. Alternatively, the system causes detection of the surface potential and/or detection of the optical both before and after a cleaning operation by the electrode cleaner. The cleaning operation will be repeated until the difference between the first and second detections falls within a predetermined range. In the above operations, if the repetitions of the operations in excess of the predetermined number of times cannot make the detection result fall within the predetermined range, the system preferably activates a warning device and/or prohibits a copying operation.

Process control stabilizing system including a cleaning device for the

A photoreceptor having a marking area whose optical reflection property differs from that of a non-marking area is formed in a portion of a surface of an electrically conductive substrate. The average line of a vertical section of the non-marking area cut across the border line with the marking area is M.sub.0 and the average line of a vertical section of the marking area cut across the border line is N.sub.0 and that straight lines touching the average lines M.sub.0 and N.sub.0 at the intersection of M.sub.0 and N.sub.0 are tangent lines M.sub.1 and N.sub.1, respectively, the acute angle .theta. between M.sub.1 and N.sub.1 is within the range of 0.degree..ltoreq..theta..ltoreq.30.degree.. Setting the angle .theta. within this range enables a photoconductive layer of a uniform characteristic to be laminated on the electrically conductive substrate even when the marking area is formed on the surface of the substrate. With this arrangement, since information for optimizing the image quality of copies is obtained from the same location of a photoreceptor drum with reference to the marking area, a photoreceptor for electrophotography always produces copies of stable image quality.

Photoreceptor for electrophotography

A box-shaped container (10) has an opening (12) and the opening is sealed tightly and doubly by a sealing material (13). The sealing material is hot-glued to a peripheral portion of the opening of the cartridge body to such an extent that the sealing material can be peeled from the peripheral part. The end portion (13a) of the sealing material is bonded at an adequate length from the free end to the face 11a of a side of the peripheral portion, and the free end portion is turned down for 180 degree angle to the outer side of the opening. Furthermore, the sealing material is bonded to the face (11b) of a opposite side of the peripheral portion side at which the free end portion (13a) is adhered and turned down to cover the opening in double covering. The sealing material also covers the turned-down end portion. The other end portion (13b) of the sealing material is attached to a roller (16), and as the user turns a handle (18) of the roller, the sealing material can be peeled off easily.

Developer cartridge having easily removable sealing material

Electrophotographic apparatus according to this invention are controlled in different ways such that quality of produced images is not affected by deterioration of the developing agent or the condition of the photoreceptor. A timer may be provided to detect the duration of a rest period to adjust the speed of development accordingly as well as by the number of copies produced. Similar control may be effected by measuring the surface voltage of the photoreceptor by a voltage detector and by adjusting the output level of the principal charger used for uniformly charging the photoreceptor prior to a development process.

Electrophotographic apparatus controlling image quality according to

An image formation apparatus having a cleaning process for removing defective toner from the developing unit during a non-image formation rotation of the photoreceptor drum. The image formation apparatus includes a reverse polarity charger for charging the photoreceptor drum to an opposite polarity from the polarity that is used for forming an electrostatic latent image. The reverse polarity charger allows defective toner to be removed from the surface of the photoreceptor during a warming-up process of the apparatus or after a predetermined number of image forming processes have been performed.

Device for removing defective developer agent from a developing unit of

A long life cleaning blade for image forming apparatus is formed of a rubber elastomer which contains, or has adhered on the surface thereof, an antistatic agent in an amount effective to prevent electrification.

Cleaning blade with a surface active antistatic agent

A developing device for a copier is controlled such that if the rate at which toner is supplied into its developing tank is detected to exceed a preset reference value, stirring rollers for stirring the toner inside the developing tank are caused to rotate at a slower rate than if the toner supply rate is detected to be less than the reference value such that toner can be charged sufficiently in spite of its increased rate of supply and an image of good quality can be obtained.

Developing device for copier

Before a photoreceptor for an electrophotographic image forming apparatus is uniformly charged at the beginning of a process for forming a latent electrostatic image thereon, the photoreceptor is exposed to charge-removing light for stabilizing the surface potential such that a high-quality image can be obtained. The level of exposure is modified in view of the fatigue and recovery characteristics of the photoreceptor. During a continuous operation of the photoreceptor, the level is logarithmically reduced. When the photoreceptor is started again after a rest period, the initial level of exposure is adjusted by logarithmically increasing it according to the length of the rest period as well as in view of the level of exposure prior to the rest period.

Method of stabilizing surface potential of photoreceptor for

An image transfer device has a screening plate attached to and protruding from a paper guide so as to partially block the corona ion current from its transfer charger such that only the forward portion of an incoming transfer paper sheet already in contact with the surface of a photosensitive drum is exposed to the current. An elastic guide plate separated from the drum surface by only about 1 mm serves to allow transfer paper sheet of different stiffness to come into contact with the drum surfaces at a predetermined position.

Image transfer device

A discharging apparatus for use in a copying machine for discharging the photoreceptor layer laminated on a drum includes a short wavelength light source for producing a light having a wavelength shorter than 6000 angstrom, and a long wavelength light source for producing a light having a wavelength longer than 6200 angstrom. A control circuit is provided for controlling both light sources such that both light sources are turned on during at least one complete rotation of the drum before an exposure of a light image on the photoreceptor layer.

Discharging apparatus and method for use in a copying machine

A copying machine with a multiple transport function having a separation charger for separating from the photoreceptor surface copy paper with an image transferred thereon and a circulating transport passage formed from the paper discharge block to the paper feed block so that it is possible to select the single-sided copy mode for allowing the copy paper to be discharged outside the copying machine after the copying process, the duplex copy mode for allowing the copy paper undergoing one copying process to be led through the circulating transport passage to the copying process block as reversed, or the composite copy mode for allowing the copy paper undergoing one copying process to be led through the circulating transport passage to the copying process block without being reversed. The copying machine with a multiple transport function includes a current controller which sets current applied to the separation charger for the second copying process at a larger value in the composite copy mode and at a smaller value in the duplex copy mode than that for the copying process in the single-sided copy mode.

Copying machine with multiple transport function

Disclosed is a useful method of removing a charge from an electrophotographic photoreceptor provided with insulation layers on its surface by radiating light containing a minimum of 6,000 angstroms of peak wave length onto said photoreceptor simultaneously with a corona discharge. To realize this, a filter is applied so that light containing a minimum of 6,000 angstroms of peak wave length can be generated.

Method of removing a charge from an electrophotographic photoreceptor

Image intensity adjustment in a copying machine is performed by simultaneously adjusting both a bias voltage to be applied to a developer unit of the copying machine and the intensity of light to be projected at an exposure section onto a photosensitive medium of the copying machine. Adjustment is facilitated by operatively connected variable resistors.

Growing community of inventors

Kyoto, Japan

Hiroshi Kinashi