Abstract: A magnetic toner comprises a binder resin and a magnetic material.The magnetic toner has a volume average particle diameter of not more than 9 .mu.m and the variation coefficient of particle size distribution, (.sigma.T/D).times.100, of the magnetic toner satisfies the following condition:25.ltoreq.(.sigma.T/D).times.100.ltoreq.35where D represents a volume average particle diameter (.mu.m) of the magnetic toner and .sigma.T represents a value of standard deviation of the volume particle size distribution of the magnetic toner,The magnetic material has a number average particle diameter of from 0.1 .mu.m to 0.2 .mu.m and the variation coefficient of particle size distribution, (.sigma./X).times.100, of the magnetic material satisfies the following condition:(.sigma./X).times.100.ltoreq.40where X represents a number average particle diameter (.mu.m) of the magnetic material and .sigma. represents a value of standard deviation of the number particle size distribution of the magnetic material.

Abstract: A smoking device for smoking of a cigarette having a tip end portion and a burning end portion has a housing assembly defining a heating chamber and having an exhaust port, an air port and an opening which all communicate with the heating chamber, a mouthpiece for supporting the cigarette such that the burning end portion of the cigarette is located within the heating chamber, a burner device for heating and decomposing at least one of the component of the main-flow smoke and the component of sub-flow smoke, and a smoke passage having an inlet as a first end portion, from which main-flow smoke is introduced, and a second end portion, from which the main-flow smoke is exhausted. The second end portion of the smoke passage is located within the heating chamber and surrounds the flame of the burner device so as to direct the main-flow smoke towards the tip of the flame of the burner device.

Abstract: An ink jet printer includes apparatus for preventing ink clogs from interfering with the flow of ink from a printing nozzle during a printing operation. The ink-declogging apparatus includes a vacuum pump having a vacuum chamber and a member movable with respect to such chamber to adjust the pressure therein. A printing nozzle is operably coupled to the chamber when the printing nozzle is not being used in a print operation. A stepper motor controls the position of the movable member relative to the chamber to selectively provide at least two different preset levels of vacuum (suction) to the printing nozzle. Having the capability of controlling the level of vacuum applied to the printing nozzle, a high vacuum need only be applied in situations warranting its use (e.g. to remove ink clogs), and the waste of ink (by an unnecessarily high vacuum) can be avoided.

Abstract: A dry toner for developing an electrostatic latent image comprising toner particles and fine particles of a lubricant coated with an inorganic compound fine powder and an image formation method using the same. The toner is excellent in fluidity, cleaning properties, stability with environmental changes, and durability.

Abstract: The present invention provide a toner for developing an electrostatic image. The toner comprises a binder resin and a coloring agent. The binder resin comprises a styrene type binder resin. The amount of an aldehyde contained in the binder resin is not more than 0.005% by weight based on the weight of the toner. The binder resin is produced by a process comprising the steps of preparing a monomer composition comprising a polymerizable monomer containing at least not less than 50% by weight of a styrene monomer, and a polymerization initiator, and subjecting said monomer composition to suspension polymerization in an aqueous medium having dissolved oxygen in an amount of not more than 2.5 mg/lit to form a styrene polymer or copolymer containing an aldehyde monomer in an amount of not more than 0.01% by weight.

Abstract: A toner for developing electrostatic images contains a binder resin and a colorant or a magnetic material. The binder is prepared by polymerizing ethylenically unsaturated monomer(s) in the presence of less than 0.1% by weight of the monomer(s) of a radical polymerization initiator. The resulting polymer or copolymer is dissolved in a polymerizable monomer and solution or suspension polymerized with a radical polymerization initiator. The resulting binder resin is substantially free of fragments of radical polymerization initiator which tend to bond to molecular chain terminals.

Abstract: A toner for developing electrostatic latent images with a good combination of fixability, anti-offset characteristic, anti-sticking characteristic and pulverizability contains a composition comprising a colorant or magnetic material and a binder resin. The binder resin has 0.1 to 60 wt. % of a chloroform-insoluble or a THF (tetrahydrofuran)-insoluble component and a THF-soluble component, the THF-soluble providing a molecular weight distribution in the chromatogram of GPC (gel permeation chromatography) thereof such that there is a main peak in the molecular weight range of 1,000 to 25,000 and a sub-peak or shoulder in the molecular weight range of 2,000 to 150,000. The binder resin may suitably be obtained through two polymerization steps including a solution polymerization step and a suspension polymerization step.

Abstract: A toner for developing electrostatic latent images with a good combination of fixability, anti-offset characteristic, anti-sticking characteristic and pulverizability is provided as a composition comprising a colorant or magnetic material and a binder resin. The binder resin has 0.1 to 60 wt. % of a chloroform-insoluble or a THF (tetrahydrofuran)insoluble and a THF-soluble, the THF-soluble providing a molecular weight distribution in the chromatogram of GPC (gel permeation chromatography) thereof such that there are a main peak in the molecular weight range of 1,000 to 25,000 and a sub-peak or shoulder in the molecular weight range of 2,000 to 150,000. The binder resin may suitably be obtained through two polymerization steps including a solution polymerization step and a suspension polymerization step.

Abstract: A binder resin comprises a vinyl copolymer, a mixture of vinyl copolymers, or a mixture of a vinyl copolymer and a vinyl polymer. A resin component with a molecular weight of not more than 10,000 is contained in an amount of from 5 to 50% by weight based on the whole resin. The vinyl copolymer or the mixture of vinyl copolymers has an acid anhydride group and a carboxyl group.

Abstract: A magnetic toner for developing an electrostatic image comprises a binder resin and a spherical magnetic powder. The spherical magnetic powder comprises spherical magnetic particles. The spherical magnetic particle has a surface layer having composition different from its core. The surface layer is formed of a ferrite having an oxide of a divalent metal other than iron in an amount of from 1.5 to 13 mol % in terms of divalent metal ion.

Abstract: The present invention provide a toner for developing an electrostatic image. The toner comprises a binder resin and a coloring agent. The binder resin comprises a styrene type binder resin. The amount of an aldehyde contained in the binder resin is not more than 0.005% by weight based on the weight of the toner. The binder resin is produced by a process comprising the steps of preparing a monomer composition comprising a polymerizable monomer containing at least not less than 50% by weight of a styrene monomer, and a polymerization initiator, and subjecting said monomer composition to suspension polymerization in an aqueous medium having dissolved oxygen in an amount of not more than 2.5 mg/lit to form a styrene polymer or copolymer containing an aldehyde monomer in an amount of not more than 0.01% by weight.

Abstract: A dry developer for developing electrostatic images comprises a) toner particles comprising 100 parts by weight of a binder resin and 1-20 parts by weight of polyalkylene having a ratio of weight average molecular weight to number average molecular weight of 2.0-10.0 and Z average molecular weight determined by gel permeation chromatography of 10,000-200,000, and containing 5-60% by weight of a component soluble in n-hexane at boiling point, kinetic friction coefficient of the toner particles being 0.20-0.50, and b) non-magnetic inorganic fine powders having BET specific surface area according to a nitrogen adsorbing method of 0.5-500 m.sup.2 /g.An image forming method comprises using the dry developer to develop electrostatic latent images on a photosensitive member having a surface hardness of 8 g or more, transferring the developed images to a receiving member, and removing the toner particles remaining on the photosensitive member by a cleaning means accompanying abrasion.

Abstract: According to a smoking device of the present invention, major and a minor smoke streams given out during smoking are temporarily stored in a storage section by means of a forcible sucking device. The storage section is taken out to the outdoors later, and the stored smoke is exhausted. The forcible sucking device comprises fans, a pump, or the like, or it utilizes the gravitational force or spring force.

Abstract: A toner for developing electrostatic latent images with a good combination of fixability, anti-offset characteristic, anti-sticking characteristic and pulverizability is provided as a composition comprising a colorant or magnetic material and a binder resin. The binder resin has 0.1 to 60 wt. % of a chloroform-insoluble or a THF (tetrahydrofuran)-insoluble and a THF-soluble, the THF-soluble providing a molecular weight distribution in the chromatogram of GPC (gel permeation chromatography) thereof such that there are a main peak in the molecular weight range of 1,000 to 25,000 and a sub-peak or shoulder in the molecular weight range of 2,000 to 150,000. The binder resin may suitably be obtained through two polymerization steps including a solution polymerization step and a suspension polymerization step.

Abstract: A magnetic toner for developing electrostatic images, comprising at least a binder resin and a magnetic powder; the binder resin having 10 to 70 wt. % of a THF (tetrahydrofuran)-insoluble and a THF-soluble, the THF-soluble providing a molecular weight distribution in the chromatogram of GPC (gel permeation chromatography) thereof such that it provides a rate (Mw/Mn) of weight-average molecular weight (Mw)/number-average molecular weight (Mn).gtoreq.5, there are a peak in the molecular weight range of 2,000 to 10,000 and a peak or shoulder in the molecular weight range of 15,000 to 100,000 and a component having a molecular weight of 10,000 or smaller is contained in an amount of 10-50 wt. % based on the binder resin; the magnetic powder comprising spherical magnetic particles having a bulk density of 0.6 g/ml or larger.

Abstract: A magnetic dry developer, comprising negatively chargeable insulating magnetic toner particles containing, at least, a binder resin, a magnetic substance, and an organo-chromium or -zinc complex; cerium oxide particles containing CeO.sub.2 as a predominant component and having a volume average particle size of 1.0 to 4.0 microns, a heating loss of 0.5 wt. % or less on heating up to 100.degree. C. and a BET specific surface area of 15 m.sup.2 /g or less as measured by the nitrogen adsorption method; and hydrophobicity-imparted negatively chargeable silicon oxide particulates. The cerium oxide particles have a function of disintegrating particularly the hydrophobicity-imparted silicon oxide particulates and enhance the attachment thereof to the toner particles, whereby the developing characteristics including the magnetic triboelectric chargeability are stabilized from the initial stage of electrophotographic copying operation.

Abstract: A magnetic toner for developing characteristic latent images is disclosed. The magnetic toner has a magnetic material content W (wt. %) of 20-60 wt. %, a saturation magnetization .sigma..sub.s of W emu/g or higher as measured at a magnetic field of 10 k Oe, and a bulk resistivity of 10.sup.13 .OMEGA..cm or higher. Because of the combination of a high .sigma..sub.s and a high resistivity, the magnetic toner has good image forming characteristics including image density, reproducibility of thin lines and transferability under various environmental conditions and for a long period of image formation.

Abstract: A dry developer for developing electrostatic images comprises (a) toner particles comprising 100 parts by weight of a binder resin and 1-20 parts by weight of polyalkylene having a ratio of weight average molecular weight to number average molecular weight of 2.0-10.0 and Z average molecular weight determined by gel permeation chromatography of 10,000-200,000, and containing 5-60% by weight of a component soluble in n-hexane at boiling point, kinetic friction coefficient of the toner particles being 0.20-0.50, and (b) non-magnetic inorganic fine powders having BET specific surface area according to a nitrogen adsorbing method of 0.5-500 m.sup.2 /g.An image forming method comprises using the dry developer to develop electrostatic latent images on a photosensitive member having a surface hardness of 8 g or more, transferring the developed images to a receiving member, and removing the toner particles remaining on the photosensitive member by a cleaning means accompanying abrasion.

Abstract: Spherical toners with magnetic material dispersed internally of the toner particles are obtained by a process for producing toners having the step of suspension polymerization of a dispersion of a toner material containing a magnetic material, a synthetic resin monomer and a polymerization initiator dispersed in a dispersion medium which is substantially incompatible with said monomer.

Abstract: A process for producing toner, which comprises dispersing a monomer system comprising a polymerizable monomer and a polar polymer in a dispersion medium containing a dispersant having a charging polarity opposite to that of said polar polymer, and subjecting said monomer system to the suspension polymerization. By this process, toner particles excellent in fixing characteristic, developing characteristic and abrasion resistance can be obtained with a narrow particle size distribution.