Abstract: A toner for developing an electrostatic image, a developer for developing an electrostatic image, a process for producing them, and a process for forming an image that provide excellent developing and transferring performance and also provide excellent performance stability, as well as high image quality and reliability are provided. The problem can be solved by a toner for developing an electrostatic image having a particle size distribution index on a small particle side GSDpS in number distribution of a particle diameter of about 1.27 or less, GSDpS is D50p/D16p, D50p represents a particle diameter providing, a particle diameter accumulation in number distribution of 50%, and D16p represents a particle diameter providing a particle diameter accumulation in number distribution of 16% from a small diameter side.

Abstract: A toner for developing an electrostatic image excellent in fixing property and particularly in light transmissibility and coloring property and satisfying high image quality and high reliability, and a process for producing the same, as well as a developer for an electrostatic image and a process for forming an image are provided. The toner for developing an electrostatic image contains at least a resin component and colorant particles, and the colorant particles exhibit a dispersion state inside the toner observed by a transmission electron microscope. The dispersion state satisfies two conditions, where (1) the colorant particles have a dispersion average particle diameter of 100 nm or less, and (2) the colorant particles have a content of coarse particles of a diameter of 400 nm or more 5% by number or less of the total of the colorant particles.

Abstract: An inexpensive method for producing trimethylhydroquinone free from the problem of the disposal of waste catalyst, which method comprises the steps of: (1) reacting isophorone in the presence of an acid catalyst and recovering &bgr;-isophorone by distillation, (2) oxidizing the &bgr;-isophorone in the presence of amorphous carbon and a base to obtain 4-oxoisophorone, (3) reacting the 4-oxoisophorone with an acid anhydride in a liquid phase or with a carboxylic acid in a vapor phase in the presence of a solid acid catalyst to obtain trimethylhydroquinones, and (4) hydrolyzing the trimethylhydroquinones to obtaining trimethylhydroquinone.

Abstract: Disclosed is an electrostatic image developing toner comprising a binder resin and a coloring agent, which exhibits a volume-average particle distribution GSDv of not more than 1.26 and an acid value of from 1.0 to 20 mgKOH/g and contains a surface active agent in an amount of not more than 3% by weight in the particulate toner and an inorganic metal salt having an electric charge having a valence of two or more in an amount of from not less than 10 ppm to not more than 1% by weight.

Abstract: An electrostatic-charged image developing toner containing a binder resin and a coloring agent, which is excellent in the fixing characteristics, has high charging uniformity and stability, and gives excellent images, wherein the crosslinking molecular weight Mc of the toner obtained by a temperature dispersion measurement in the dynamic viscoelasticity of the toner is from about 1.6.times.10.sup.4 to 3.5.times.10.sup.6, or the crosslinking density Me thereof is from about 1.6.times.10.sup.-8 to 3.5.times.10.sup.-6 /Kmol.

Abstract: A toner composed of binder resin and carbon black particles has a volume-average particle diameter (D.sub.50) of 2.0 to 9.0 microns and a volume-average particle size distribution index (GSDv) of 1.25 or less. Carbon black particles adhering to the surfaces of toner particles have an absorption of 0.250 or less for ultraviolet radiation having a wavelength of 600 nm. Disclosed also are a method for producing the toner, a developer for developing an electrostatic latent image and a method in which the developer is used for forming animage.

Abstract: It is to provide a toner for developing static charge and a process for producing the same that is excellent in peelability of the fixing sheet, adhesion of the fixed image, bending resistance of the fixed image, Dispersibility of the releasing agent in the toner and transparency on an OHP sheet, and can provide a high quality fixed image, as well as a developer and a process for forming an image. It relates to a toner for developing electrostatic charge of the invention including a coloring agent and a binder resin and a process for producing the same, wherein the relaxation modulus of elasticity G(t) at a relaxation time t=10.times.Dt (wherein Dt represents a heating time on fixing) obtained from measurement of dynamic viscoelasticity is adjusted to a range of from 2.0.times.10.sup.2 to 3.0.times.10.sup.3 Pa, or the relaxation modulus of elasticity G(t=0.01) at a relaxation time of 0.01 sec obtained from measurement of dynamic viscoelasticity is adjusted to a range of from 2.0.times.10.sup.2 to 3.0.times.

Abstract: Disclosed is toner for developing an electrostatic image, which toner has a volume average particle size distribution index (GSDv) of 1.3 or less, and a ratio of the volume average particle size distribution index (GSDv) to a number average particle size distribution index (GSDp), i.e., (GSDv/GSDp), of 0.95 or more. A method suited for producing the toner for developing an electrostatic image comprises the steps of producing a dispersion liquid of flocculated particles by forming the flocculated particles in a dispersion liquid containing at least resin particles dispersed therein, forming adhered particles by admixing a liquid dispersion comprising fine particles dispersed therein with the dispersion liquid comprising the flocculated particles so that the fine particles adhere to the flocculated particles, and forming toner particles by fusing the adhered particles upon heating.

Abstract: The present invention provides a method of preparing a toner for electrostatic charge image development comprising the steps of a liquid mixture preparation process for preparing a liquid mixture by mixing at least a resin particle dispersion prepared by dispersing resin particles in a solution including a dispersing agent having a polarity, and a coloring agent particle dispersion prepared by dispersing coloring agent particles in a solution including a dispersing agent having a polarity, an aggregated particle dispersion preparation process for preparing an aggregated particle dispersion by forming aggregated particles in the liquid mixture, and a fusion process for fusing the aggregated particles by heating, wherein the first dispersing agent and the second dispersing agent have the same polarity, a toner for electrostatic charge image development obtained by the method, an electrostatic charge image developer containing the toner and a carrier for electrophotography, and an image forming method comprising

Abstract: The toner for developing an electrostatic charge image has a sharp particle size distribution, an improved cleaning property even if the toner has small particle diameter, and a stable charging property, developing property and transfer property regardless of change of environment. By use of the toner, a highly precise image may be obtained.In a toner for developing an electrostatic charge image prepared by a wet process, the dielectric loss factor of the toner particles is 100 or less. In addition, when the toner particles are dissolved in an organic solvent and mixed with deionized water, the electrical conductance of the solution is desirably 100 ms or less and the surface tension thereof is desirably 20 mN or more. The toner may be obtained by forming agglomerated particles with stirring in a dispersion in which resin particles are dispersed to granulate; heating the toner particles to Tg or higher of the binder resin; stirring; and cleaning.

Abstract: According to the present invention, the method for producing toner for developing an image of electrostatic charge comprises the steps of producing a dispersion liquid of flocculated particles by forming the flocculated particles in a dispersion liquid comprising at least dispersed resin particles, forming combined particles by dispersing a liquid dispersion comprising dispersed fine resin particles into the dispersion liquid of flocculated particles so that the fine resin particles adhere to the flocculated particles and forming toner particles by fusing the combined particles by heating, wherein the molecular weight distribution curve of the resin in the toner particles by a gel permeation chromatography has at least two peaks or shoulders. According to the present invention, it is possible to produce toner for developing an image of electrostatic charge which is particularly superior in chargeability and the stability of the chargeability.

Abstract: The present invention relates to a production method of a toner for developing an electrostatic charge image having an excellent charging property, the method comprising the steps of: forming aggregative particles in a dispersion including at least dispersed resin particles to prepare an aggregative particle dispersion; adding a resin-containing fine particle dispersion containing dispersed resin-containing fine particles into the aggregative particle dispersion and mixing therewith to form adhered particles having said resin-containing fine particles adhering to said aggregative particles; and heating said adhered particles to be fused, wherein concentration of a dissociation group of said resin-containing particles per unit volume is lower than that of a dissociation group of said resin-containing fine particles per unit volume.

Abstract: The present invention discloses a preventive or ameliorant of hypertension or medical symptoms caused by it and a food or beverage that prevents or ameliorates hypertension or medical symptoms caused by it that contain for its active ingredient dioxabicyclo?3.3.0!octane derivative represented by the formula (2). ##STR1## wherein, R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5 and R.sup.6 are respectively and independently a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, or R.sup.1 and R.sup.2 and/or R.sup.4 and R.sup.5 collectively represent a methylene group or ethylene group, and n, m and L represent 0 or 1.

Abstract: The present invention provides a toner for developing an electrostatic charge image having excellent characteristics including a developing property, transfer property, fixing property, and cleaning property, and an efficient production method thereof. The present invention relates to a production method of a toner for developing an electrostatic charge image comprising: a first step of forming aggregative particles in a first dispersion including at least dispersed resin particles to prepare an aggregative particle dispersion, a second step of adding a fine particle dispersion containing dispersed fine particles into said aggregative particle dispersion and mixing therewith to form adhered particles having said fine particles adhering to said aggregative particles, and a third step of heating said adhered particles to be melted.

Abstract: A method for producing cyclopentadienes which comprises the step of cyclodehydration of an unsaturated carbonyl compound having a specific chemical structure in a vapor phase in the presence of a specific solid acid catalyst. The cyclopentadienes of the invention can be produced in a high yield from inexpensive starting materials through a simplified reaction process and are useful as intermediate compounds for organic synthesis.

Abstract: A suction silencer apparatus having a high silencing performance and a superior space efficiency is provided. The suction silencer apparatus is installed on an engine having a plurality of silencer chambers on a suction passage and includes a first silencer chamber surrounding a bent portion of the suction passage and communicating with the suction passage, a second silencer chamber arranged integrally with the first silencer chamber at an inner side of the bent portion of the suction passage, and a connecting device arranged at the inner side of the bent portion of the suction passage for connecting the first silencer chamber with the second silencer chamber.

Abstract: A method for preparing a high-purity p-isobutylstyrene is here disclosed which comprises the first step of reacting o- and/or m-isobutylethylbenzene, if necessary, together with isobutylbenzene, in the presence of an acid catalyst in a liquid phase at a reaction temperature of -10.degree. to 600.degree. C. so that the production of sec-butylethylbenzene in butylethylbenzene may not exceed 20% by weight, in order to form a mixture of p-isobutylethylbenzene and sec-butylethylbenzene; and the second step of bringing the mixture of p-isobutylethylbenzene and sec-butylethylbenzene recovered from the first step into contact with a dehydrogenation metal catalyst containing at least one metal selected from the groups Ib, IIb, VIa, VIIa and VIII of the periodic table at a reaction temperature of 300.degree. to 650.degree. C. under a reaction pressure of 50 kg/cm.sup.2 or less in a gaseous phase.

Abstract: The present invention relates to provide a drawn optical transmission medium having excellent heat resistance and a continuous refractive index distribution in a good productivity at a low cost, and the disadvantages in a conventional synthetic resin optical transmission medium can be eliminated, which method is characterized by a step of crosslinking a polymer having a continuous refractive index gradient distributed from the peripheral portion to the central portion in its cross section and having a crosslinkable functional groups, after the step of heating and drawing.

Abstract: A method for preparing a polymer rod for optical transmission media. The process involves copolymerization of monomers having different boiling points by removal of monomer vapor during polymerization. The process results in a transition in refractive index along the radial direction of the polymer rod.

Abstract: A carrier for developing an electrostatic latent image, which carrier comprises core particles having formed thereon a resin coating layer, in which the resin coating layer comprises a fluorine-containing resin and a second resin having a softening point lower than that of the fluorine-containing resin, and the resin and the second resin each are partially exposed on the surface of said resin coating layer. The carrier may be produced by a process comprising the steps of: dry-blending core particles, a fluorine-containing resin, and a second resin having a softening point lower than that of said fluorine-containing resin; and melting the resin blend to coat said core particles. The carrier is excellent in stability with time and environmental changes, causes no adhesion, and is less consumed.