Abstract: An image forming method including the steps of providing a black toner, a yellow toner, a magenta toner and a cyan toner, wherein each toner includes a binder resin, a colorant and an external additive, wherein the external additive contains a silica, and wherein the content by weight of the external additive in the black toner is greater than any one of those in the yellow, magenta and cyan toner; developing an electrostatic latent image formed on an image bearing member with one of the toners to form a toner image; repeating the developing operation mentioned above using the other toners; transferring the toner images to a receiving material; and heating the toner images using a non-contact fixing device to fix the toner images.

Abstract: A color developer is described that contains a toner and a resin-coated carrier, wherein the toner contains a hydrophobic particulate titania and a charge controlling agent, and the charge controlling agent contains an aromatic hydroxycarboxylic acid metal salt having the following formula (1): ##STR1## wherein each of Q and Q' each independently represents a residual group of an aromatic hydroxycarboxylic acid optionally substituted with an alkyl group, an aralkyl group, or an alkyl group and an aralkyl group; X is a counter ion; and M is a metal. A toner is also provided that contains the above charge controlling agent.

Abstract: A toner for developing latent electrostatic images including a resin component, with the image fixing temperature of the toner being in the range of 100.degree. to 140.degree. C., and the penetration of the toner, measured when allowed to stand at 60.degree. C. for 4 hours in accordance with Japanese Industrial Standards (JIS) K 2235, being 5 mm or more. The resin component for the toner may include a hydrogenated petroleum resin with a hydrogenation ratio of 50% or more, and optionally polyester resin.

Abstract: In an electrophotographic or electrostatic image forming device, the toner concentration of a two-component developer, i.e., a mixture of toner and carrier is measured on the basis of an output of a magnetic bridge type concentration sensor responsive to the magnetic permeability of the developer. The sensor has a surface whose mean roughness along the center line is less than 0.4 .mu.m Ra.

Abstract: A positively-chargeable toner includes a binder resin, a coloring agent, and a quaternary-ammonium-base containing copolymer with a weight-average molecular weight of 5,000 to 25,000, which included a repeat unit of formula (I), and a repeat unit of formula (II): ##STR1## wherein R.sup.1 is a hydrogen atom or a methyl group; R.sup.2 is a hydrogen atom or a methyl group; R.sup.3 is an alkylene group, and R.sup.4, R.sup.5 and R.sup.6 are an alkyl group. The quaternary-ammonium-base containing copolymer may further include a repeat unit of formula (III): ##STR2## wherein R.sup.7 is a hydrogen atom or a methyl group; and R.sup.8 is an alkyl group.

Abstract: A toner for developing latent electrostatic images composed of a continuous phase containing a binder resin, and a disperse phase dispersed in the form of finely-divided disperse phases in the continuous phase, containing a resin which is not the same as the binder resin for use in the continuous phase, and finely-divided particles of a releasing agent which are dispersed in the resin, with a coloring agent being dispersed in the continuous phase and/or the disperse phase.

Abstract: A two-component dry type developer for developing latent electrostatic images comprises (i) toner particles with an average particle diameter of 14 .mu.m or less and (ii) carrier particles with an average particle diameter of 70 .mu.m or less, with the ratio of the average particle diameter of the toner particles to the average particle diameter of the carrier particles being 1/5 or less, with a dynamic resistance of 1.0.times.10.sup.8 .OMEGA. or less, and the specific triboelectric charge quantity generated between the toner particles and the carrier particles per unit weight of the toner particles is 25 .mu.C/g or more.

Abstract: A process for fabricating a PTC thermistor device. A pair of opposing electrodes are formed on either major surface of a ceramic plate PTC thermistor element. Metallic plate heat radiation fins are secured to the opposing electrodes by brazing in a non-oxidizing environment. The PTC thermistor element is then heat treated in an oxidizing environment. Optionally, the opposing electrodes may include shield layers for preventing emission of gas from the PTC thermistor element during brazing.

Abstract: A dry type toner for electrophotography is disclosed which comprises as the main components (a) a coloring agent; and (b) a polyol resin serving as a binder agent in an effective amount, the polyol resin being prepared by subjecting a bisphenol-type epoxy resin containing epoxy groups, which may contain secondary hydroxyl groups, to reaction steps (1), (2) and (3), or steps (2) and (3), in any sequential combination, until substantially no epoxy groups remain in the polyol resin, wherein the reaction step (1) comprises a step of causing the epoxy groups in the bisphenol-type epoxy resin to react with a primary amine; the reaction step (2) comprising a step of causing the epoxy groups to react with a compound containing one active hydrogen capable of reacting with the epoxy groups; and the reaction step (3) comprising a step of esterifying at least part of the secondary hydroxyl groups or hydroxyl groups produced in the bisphenol-type epoxy resin by reaction step (1) and/or reaction step (2) by use of an ester

Abstract: A toothbrush holder for infants including a casing body having a substantial contour of an animated character and an aperture at the top thereof, a back plate fitted to a back of the casing body, side portions projecting and integrally formed with a lower portion of the casing body with a space between the side portions, a holding arm pivotally engaged at the side portions and projecting outwardly from the space between the side portions and having a recess at an outward end for releasably holding a toothbrush therein, a lever projectable outwardly through the aperture, the lever being pivotally connected with an inward end of the holding arm and having a name-plate at a top end thereof, and a suction disk fitted to the back plate to thereby releasably fix the holder to a selected place.

Abstract: The present invention relates to the positively chargeable black toner particles which comprise binder resins, carbonblack as a main colorant, quaternary anmonium salt of the following formula (I) as a charge control agent and .beta.-form Cu-phthalocyanine as a stabilizing agent for chargeability of toner particles without being affected by the change of environmental conditions. ##STR1## Wherein R.sub.1 is C.sub.1 -C.sub.8 alkyl or benzyl, R.sub.2 and R.sub.3 are each C.sub.1 -C.sub.18 alkyl, R is C.sub.1 -C.sub.118 alkyl or benzyl, X is hydroxy or amino, and Y is hydoroxy or hydrogen; (c) .beta.-form Cu-phthalocyanine; and (d) carbonblack.The present invention further relates to the two component dry-type developer composed by the improved above said positively chargeable toner particles and the carrier particles coated with silicone polylmers which have the strong durability without being changed to a supent carrier particles for a use of long time period.

Abstract: A toner for developing latent electrostatic images is disclosed, which comprises a binder resin comprising a component selected from the group consisting of: (1) a mixture of the ternary copolymers of styrene, methyl acrylate, and ethyl acrylate, (2) a mixture of the binary copolymers of two monomers from among the monomers of styrene, methyl acrylate, and ethyl acrylate and homopolymers containing the remaining monomer or the copolymers of that monomer and the other monomers, and (3) a mixture of the respective homopolymers.

Abstract: A magenta toner is disclosed, which comprises a coloring composition comprising a thioindigo pigment, and a xanthene dye having general formula (I) or a laked xanthene dye thereof, and a binder resin: ##STR1## wherein R.sup.1, R.sup.2, R.sup.5, R.sup.6, and R.sup.7 each represent hydrogen or a lower alkyl group; R.sup.3 and R.sup.4 each represent a lower alkyl group; and A.sup.- represents halogen.

Abstract: The disclosure describes carrier particles for use in a two-component dry-type developer, consisting of core particles which are coated with a silicone resin hardened by an organic tin catalyst.

Abstract: A toner for developing latent electrostatic images is disclosed, which comprises a colorant, and a binder agent comprising (i) polyester resin or epoxy resin, and (ii) styrene - methyl acrylate copolymer.

Abstract: Carrier particles for use in a two-component dry-type developer for developing latent electrostatic images comprising a core particle and a silicone resin layer coated on the core particle, the silicone resin layer comprising a silicone resin, an organic tin compound and finely-divided electroconductive particles.

Abstract: Carrier particles are disclosed for use in a two-component dry-type developer for developing latent electrostatic images to visible images, for use in electrophotography, electrostatic recording methods and electrostatic printing methods, which carrier particles are coated with a silicone resin coating layer having high resistance to abrasion and the so-called "spent phenomenon" while in use, and which therefore can be used repeatedly for a long period of time, yielding developed images with high quality. The high resistance to abrasion of the silicone resin coating layer is attained by adding to the silicone coating layer, as an inorganic fortifying agent against abrasion, silicon carbide or potassium titanate.

Abstract: Carrier particles for use in a two-component dry-type developer for developing latent electrostatic images are disclosed, which core particle comprises a core particle and a silicone resin layer coated on the core particles, and the silicone resin layer contains an organic tin compound, which serves as a catalyst for hardening the silicone resin layer in the course of the formation of the silicone resin layer on the core particle under application of heat thereto, with a concentration gradient in the direction of the thickness of the silicone resin layer towards the outer surface of the carrier particles.

Abstract: A two-component dry-type developer which comprises carrier particles coated with silicone resin and toner particles containing as a negative polarity control agent a monoazo metal complex dye. As the monoazo metal complex dye, the following metal complex dye is preferable for use in this two-component dry-type developer: ##STR1## wherein X, Y and Z independently represent hydrogen, halogen, a carboxyl group, a hydroxyl group, a nitro group, a sulfo group or a sulfonamide group; and A.sup.+ represents H.sup.+, K.sup.+, Na.sup.+ or an aliphatic ammonium cation.

Abstract: A process for manufacturing a sheet having a chip-like design composed of a plurality of chips densely aligned in a plane without overlapping and a solidified binder uniformly filling the interstices among the chips and firmly and integrally bonding the chips to one another in sheet form. The sheet is useful as a floor material, wall material, and the like.