Abstract: A positively chargeable toner includes a plurality of toner particles each including a toner mother particle and an external additive attached to a surface of the toner mother particle. The external additive includes first resin particles each having a surface to which a cationic surfactant is attached and second resin particles each having a surface to which a cationic surfactant is attached. The first resin particles have a hydrophobicity of at least 15% and no greater than 30%. The second resin particles have a hydrophobicity of at least 50% and no greater than 80%. A first resin particle coverage ratio and a second resin particle coverage ratio each are at least 10% and no greater than 30%. Each blocking rate of the first resin particles and the second resin particles is no greater than 30% by mass.
Abstract: A positively chargeable toner includes a plurality of toner particles. Each of the toner particles includes a toner mother particle and an external additive adhering to a surface of the toner mother particle. The external additive includes a plurality of resin particles. Each of the resin particles has a resin mother particle and a coat layer covering at least a portion of a surface of the resin mother particle. The coat layer contains a specific vinyl resin.
Abstract: A first aspect is a toner production method in which an organosilicon compound is condensed in a surfactant-containing aqueous medium with a specific surface tension, in which a resin particle is dispersed, to produce a toner having the condensate of the organosilicon compound on the surface of the resin particle, and a second aspect is a toner production method in which an organosilicon compound is condensed in an aqueous medium which has a surfactant and a specific metal salt and in which a resin particle is dispersed, to produce a toner having the condensate of the organosilicon compound on the surface of the resin particle.
Abstract: The toner has a toner particle that contains a binder resin, a colorant, a release agent, and a crystalline polyester, wherein the release agent contains an ester wax, and the peak top temperature of the maximum endothermic peak of the ester wax as measured with a differential scanning calorimeter is from 65° C. to 85° C., the ester wax satisfies specific conditions and the crystalline polyester satisfies specific conditions, the toner contains from 3.0 parts by mass to 20.0 parts by mass of the crystalline polyester per 100 parts by mass of the binder resin, and the mass ratio of the ester wax to crystalline polyester is from 25/75 to 75/25.
Abstract: A positively chargeable toner includes a plurality of toner particles. The toner particles each include a toner mother particle and an external additive attached to a surface of the toner mother particle. The toner mother particle contains a binder resin and a wax. The external additive includes a plurality of antioxidant particles. Each of the antioxidant particles includes a base particle containing an antioxidant and having a surface treated with a surface treatment agent. The surface treatment agent has a first functional group and a second functional group in a molecule thereof. The first functional group has stronger positive chargeability than the base particle. The second functional group has stronger hydrophobicity than the base particle.
Abstract: A toner is provided. The toner includes toner particles each including a mother particle and external additive particles covering the mother particle. In a SEM image of the toner, toner particles having a ratio Sd/St of from 5% to 50% are present at a frequency of 15% or more, where Sd representing an area of a largest recessed portion D of each toner particle and St representing whole area of the toner particle, Sd and St determined from the SEM image magnified and binarized to discriminate recessed portions and projected portions of the toner particle from each other. An external additive coverage rate Ca at the largest recessed portion D is from 30% to 100%.
Abstract: A toner comprising a toner particle containing a resin and a colorant, wherein, with respect to a temperature-storage elastic modulus curve obtained by powder dynamic viscoelastic measurement on the toner, (I) the relative minimum values for the variation in the storage elastic modulus E? with respect to temperature T in the temperature range of at least 30° C. and not more than 180° C. have a relative minimum value of equal to or less than ?1.00×107 and the relative minimum value on the lowest temperature side is equal to or less than ?1.00×108; (II) the storage elastic modulus E? (50) of the toner at 50° C. is at least 1.00×109 and not more than 9.00×109; and (III) for a storage elastic modulus E? (120) of the toner at 120° C., E? (50) and E? (120) satisfy 1.50?[E? (50)]/[E? (120)]?3.00.
Abstract: A toner for electrophotography, which contains a binder resin, and a release agent, wherein a maximum value of loss tangent of the toner at 95° C. to 115° C. is 8 or greater, as a viscoelasticity of the toner is measured, where the loss tangent is represented by the following formula: Loss tangent (tan ?)=loss elastic modulus (G?)/storage elastic modulus (G?).
Abstract: A polyarylate resin is represented by general formula (1) shown below. In general formula (1), R1 and R2 each represent, independently of one another, a hydrogen atom or a methyl group. r and s each represent an integer of at least 0 and no greater than 49. t and u each represent an integer of at least 1 and no greater than 50. r+s+t+u=100. r+t=s+u. X and Y each represent, independently of one another, a divalent group represented by chemical formula (1-1), chemical formula (1-2), chemical formula (1-3), or chemical formula (1-4). X and Y are different from one another.
Abstract: Provided is an alloy steel powder for powder metallurgy containing an iron-based powder as a main component that is capable of achieving both high strength and high toughness in a sintered body using the same. In the alloy steel powder, the iron-based powder contains a reduced powder, and Mo content with respect to a total amount of the alloy steel powder is 0.2 mass % to 1.5 mass %, Cu powder content with respect to a total amount of the alloy steel powder is 0.5 mass % to 4.0 mass % and graphite powder content with respect to a total amount of the alloy steel powder is 0.1 mass % to 1.0 mass %.
Abstract: A method of additive manufacturing includes depositing a layer of absorptive material onto a workpiece, depositing a layer of additive manufacturing stock powder onto the workpiece, and fusing the stock powder to the workpiece using a focused energy source at a wavelength wherein the absorptive material has a higher absorptivity at the wavelength of the focused energy source than the absorptivity of the stock powder at that wavelength. The focused energy source can be a laser, e.g., with a 1064 nm wavelength, for example.
November 9, 2015
Date of Patent:
April 23, 2019
Vijay Jagdale, Tahany I. El-Wardany, Wayde R. Schmidt
Abstract: An ester wax is provided. The ester wax includes a long-chain aliphatic ester represented by the following formula: R—COO—R? wherein R represents an alky group having 13 to 23 carbon atoms and R? represents an alkyl group having 18 to 22 carbon atoms. The ester wax further includes an aliphatic alcohol having 18 to 22 carbon atoms in an amount less than 3% by mass based on a total mass of the ester wax.
Abstract: A toner for electrophotography, the toner including an amorphous polyester resin, an addition polymerization-based resin, and wax that is ester wax or carnauba wax, wherein the toner satisfies relationships represented by Formula 1 and Formula 2 below, SPr>SPw>SPd??(Formula 1) |SPr?SPw|>|SPw?SPd|??(Formula 2) where SPr is a value of a solubility parameter of the amorphous polyester resin, SPw is a value of a solubility parameter of the wax, and SPd is a value of a solubility parameter of the addition polymerization-based resin.
Abstract: Provided is a means to exhibit excellent low temperature fixability and to improve all of the heat-resistant storage property of a toner, charging uniformity, and transferability under a high temperature and high humidity condition. A toner for developing electrostatic charge image which contains at least a binder resin, in which the binder resin has a core-shell structure having a core portion which contains a hybrid crystalline polyester resin formed by chemical bonds of a crystalline polyester resin unit with an amorphous resin unit other than a polyester resin and an amorphous resin and a shell portion which contains a hybrid amorphous polyester resin formed by chemical bonds of an amorphous polyester resin unit with an amorphous resin unit other than a polyester resin.
Abstract: An electrostatic charge image developing toner set includes a white toner that includes white toner particles containing a core and a coating layer which does not contain a coloring agent and a colored toner that includes colored toner particles containing a core and a coating layer which does not contain a coloring agent, wherein with respect to a difference between an average equivalent circle diameter [Rw1] of the cores (Win) in the white toner particles and an average equivalent circle diameter [Rw2] of the white toner particles [Rw2?Rw1], and a difference between the average equivalent circle diameter [Rc1] of the cores (Cin) in the colored toner particles and the average equivalent circle diameter [Rc2] of the colored toner particles [Rc2?Rc1], a relationship of the following Expression (1) is satisfied: [Rw2?Rw1]<[Rc2?Rc1]??(1).
Abstract: The present invention relates to a process for producing a toner for development of electrostatic images, including step (1) of mixing a releasing agent and a water dispersion of resin particles (A) to obtain a water dispersion of releasing agent particles; step (2) of mixing the obtained water dispersion of the releasing agent particles and a water dispersion of resin particles (B) to aggregate the releasing agent particles and the resin particles (B), thereby obtaining aggregated particles; and step (3) of coalescing the obtained aggregated particles to obtain coalesced particles, in which the resin particles (A) include a composite resin including a segment (a1) constituted of a polyester resin and a vinyl-based resin segment (a2) containing a constitutional unit derived from a styrene-based compound; and a resin constituting the resin particles (B) includes a segment (b1) constituted of a polyester resin in an amount of not less than 50% by mass.
Abstract: An electrostatically charged image developing toner includes a particulate toner matrix containing an external additive on the surface of the particulate toner matrix. The external additive includes silica particles A and silica particles B. The silica particles A have a number average primary-particle diameter in the range of 40 to 100 nm and an average circularity in the range of 0.50 to 0.90, and are surface-modified with silicone oil. The silica particles B have a number average primary-particle diameter of 25 nm or more and smaller than the number average primary-particle diameter of the silica particles A, and are surface-modified with alkylalkoxysilane having a specific structure or silazane.
Abstract: A transfer assist member comprising a plurality of layers, one of the layers being a check film layer comprising a mixture of a polymer and a conductive component in contact with a layer of a polyalkylene furandicarboxylate.
Abstract: A toner in which the content of polysiloxane is 1% by mass or more and 15% by mass or less based on the total mass of toner particles, the polysiloxane is present in the toner as a domain of 10 nm or more and 500 nm or less, and Siloxane index (Ge)/Siloxane index (D) of the toner particles is 1.0 or less.
Abstract: A toner production method including: a melt-kneading step of melt-kneading a resin composition including a binder resin, a colorant, a wax, and a wax dispersant to obtain a melt-kneaded product; and a pulverizing step of pulverizing the melt-kneaded product. Where the temperature of the melt-kneaded product at the end of the melt-kneading step is Tk (° C.), and the softening point of the wax dispersant is Tm (° C.), the relationship of ?18?[Tk?Tm]?10 is satisfied. The wax dispersant is a polymer in which a styrene acrylic polymer is graft-polymerized to a polyolefin. The styrene acrylic polymer has a monomer unit derived from ?-methylstyrene and a monomer unit derived from a cycloalkyl (meth)acrylate.