Minolta Company, Ltd.

Minolta Camera Kabushiki Kaisha

Hitoshi Kato

Toshitaro Kohri

Takeshi Yamashita

Tomoko Yamamoto

Junji Machida

Hiroyuki Fukuda

Noboru Ito

Koji Nagai

Hiromi Kameda

Kunio Takahashi

Toshihito Shimoda

Hideyuki Yoshida

A method for manufacturing an electrophotographic toner having a mean particle diameter of more than 5 &mgr;m and less than 10 &mgr;m. For manufacturing the above size of toner, coarsely pulverized particles are pulverized to medium pulverized particles having a mean particle diameter of more than 10 &mgr;m and not more than 19 &mgr;m at first. Subsequently, the medium pulverized particles are further pulverized to small diameter particles having a mean particle diameter of more than 5 &mgr;m and less than 10 &mgr;m, and thereafter the small diameter particles are classified by a rotor type classifier.

Method for manufacturing an electrophotographic toner

A mill offers superior milling efficiency by being provided with a partition to divide a milling chamber into a first guide path and a second guide path. Particles of a milling material that have been ground at a milling area in the milling chamber are guided into a particle classifier through the first guide path, and the ground particles of the milling material that were classified by the particle classifier as requiring further milling are guided back into the milling area through the second guide path.

Mill provided with partition within milling chamber

Ink jet recorder

An ink cartridge has an ink holding chamber, an ink holding member that is placed inside the ink holding chamber and that holds ink, an ink supply outlet that connects the ink holding chamber and the outside; and a protruding member that is placed on the wall of the ink holding chamber in which the ink supply outlet is formed and that protrudes into the ink holding chamber. In the ink cartridge, the protruding member that protrudes into the cartridge presses onto the ink holding member from the area around the ink supply outlet. Consequently, the ink holding member becomes compressed by means of the protruding member, so that the ink held in the ink holding member flows out easily from the ink holding member. Further, in the ink cartridge, it is preferred that the protruding member be located such that it surrounds the supply outlet and that an ink pathway where the protruding member does not exist be created in at least part of the area around the ink supply outlet. This construction permits the ink to be sent smoothly to the ink supply outlet via the ink pathway. When the ink is sent smoothly to the ink supply outlet in this way, even shortly after the ink is supplied to the ink holding member or when a large amount of ink is supplied to the print head via the ink supply outlet for the purpose of continuous printing or purging, a sufficient amount of ink is stably led to the print head via the ink supply outlet.

Ink cartridge used in inkjet printer

In an ink cartridge, a holding section, containing a holding member for holding ink, is provided in the cartridge body; a supply port, for supplying the ink held in the holding member to the outside, and a cover member, for opening and closing the supply port, are provided in the holding section; and the cover member is urged by the holding member to close the supply port. Further, in an ink supplying apparatus, a guide pipe is provided in its apparatus body, and the guide pipe is inserted into the supply port to press the cover member into the holding section to open the supply port.

Ink cartridge and ink supplying apparatus

An ink cartridge for supplying ink to a recording head in the present invention is provided with an ink containing section containing the ink, an ink supply port for supplying the ink to the recording head, a vent hole for introducing air into the ink cartridge, a first holding member containing section containing an ink holding member for holding the ink between the ink containing section and the ink supply port, and a second holding member containing section containing the ink holding member for holding the ink between the ink containing section and the vent hole, the first holding member containing section and the second holding member containing section not communicating with each other.

Ink cartridge

The present invention related to a toner for electrophotography comprising at least a binder resin, a coloring agent and a wax for off-set prevention, in which the wax is incompatible with the resin, dispersed insularly in the resin in the form of substantially spherical and/or substantially spindle-shaped particles, the number of spindle-shaped wax-particles occupying 70% or less of the total number of wax-particles. The spherical wax-particles have a following relationship between a mean wax-particle size (Dw) and a mean toner-particle size (Dt):

Toner for electrophotography containing wax-particles dispersed in

The invention relates to a toner for developing electrostatic latent images for use in copying machines and including a thermoplastic resin and a black coloring material as main components. The black coloring material comprises a substantially non-magnetic inorganic black pigment of 5-25 cc/100 g oil absorption and 0.5-10 .mu.m average particle diameter, to obtain high quality copy images having fine textures.

Toner for developing electrostatic latent images

A dry developer for developing electrostatic latent images comprises a positive charge type carrier and a negative charge type toner. The negative charge type toner includes, as after-treating agents, fine particles of hydrophobic silica in an amount of 0.05-1.0 percent by weight relative to the toner and fine particles of hydrophobic titanium oxide in an amount of 0.1-3.0 percent by weight relative to the toner, the fine particles of hydrophobic silica and the fine particles of hydrophobic titanium oxide being contained in a weight ratio of 1:5 to 1:1.

Dry developer for developing electrostatic latent images contains silica

A developer for use in developing an electrostatic latent image according to electrography comprises a mixture of a carrier and a toner having a property of being triboelectrically charged to a positive polarity when held in frictional contact with the carrier. The toner includes a binders which is a thermoplastic resin having a Lewis acid-functional group.

Electrophotographic developer composition of improved resistance to

An electrographic developing method for developing a latent electrostatic image on a support to a toner image by brushing the image bearing surface of the support with a magnetic brush comprising a magnetic toner which comprises core particles having a low resistivity and containing a resin and a finely divided magnetic material, and secondary particles thermally adhered to part of the outer surface of each core particle and said secondary particles consisting predominantly of an insulating resin.

Growing community of inventors

Itami, Japan

Hitoshi Kato