2227results about "Developers" patented technology

A toner including a toner particle, wherein a weight-average particle size of the toner is a specific range, a domain-matrix structure in which a domain is dispersed in a matrix is observed on a cross-section of the toner, the matrix includes a crystalline resin A, the domain includes an amorphous resin B, where the domain with a major axis of 300 nm or more is defined as domain C, and the domain with a major axis of 200 nm or less is defined as domain D, a number-average major axis of the domain D is 30 to 150 nm, and a proportion of the cross-section which satisfies (i) and (ii) is 90% or more; (i) 5 to 20 of domains C are present per cross-section and an area ratio of the domain C is 10 to 30%, (ii) the domain D is observed over an entire region in the cross-section.

A toner comprises toner particles and an external additive adhering to surfaces of the toner particles, wherein the toner particle includes a crystalline polyester resin and a wax, the external additive includes organic / inorganic composite fine particles and an associated silica having two or more primary particles being associated with each other, and the toner has a softening point of 110° C. or lower.

An electrostatic charge image developing toner, an electrostatic charge image developer, a toner cartridge, a process cartridge, an image forming apparatus, and an image forming method, the electrostatic charge image developing toner having toner particles containing an amorphous polyester resin, a crystalline polyester resin, and cross-linked resin particles, the internal cross-linked resin particles are styrene-(meth) acrylic copolymer particles and have an average dispersion diameter of 100 nm or more and 300 nm or less, and when a 3 [mu] m * 3 [mu] m square region of 600 [pix] 600 [pix] is divided into n * n in a cross-sectional view of the toner particles, the average dispersion diameter of the internal cross-linked resin particles is 1 [mu] m or less, and the average dispersion diameter of the internal cross-linked resin particles is 1 [mu] m or less. When DAR (n) is the coefficient of variation of the area ratio of the added cross-linked resin particles with respect to the area of the divided regions in the n * n divided regions, and slopeF (16) is the slope of an approximate straight line in a dispersion plot plotted by changing n to 3, 4, 6, 8, 12, and 16 with log [1 / n] as the X axis and log [DAR (n)] as the Y axis, formula (1) is satisfied: 0.6 < = slopeF (16).

A toner includes toner particles each containing a binder resin. The binder resin contains 50% or more by mass of a polyester A containing 60 mol % or more of a unit derived from isophthalic acid as an acid component. The toner includes agglomerates on surfaces of the toner particles, each of the agglomerates containing silica and a resin. The toner has a CI (% by number) of 1% or more by number and 15% or less by number, CI being the percentage by number of the toner particles including the agglomerates. The percentage by number of the toner particles including the agglomerates satisfies predetermined requirements.

On the surface of a toner particle, a cohesion cluster containing a silica fine particle and a binding component is present. When a ratio by number of toner particles each having the cohesion cluster is denoted by CI (percent by number), the CI is 1 percent by number or more and 15 percent by number or less. When a ratio by number of toner particles each having the cohesion cluster in a toner subjected to processing under a weak ultrasound condition A is denoted by Ca (percent by number) and a ratio by number of toner particles each having the cohesion cluster in a toner subjected to processing under a strong ultrasound condition B is denoted by Cb (percent by number), the CI, the Ca, and the Cb satisfy formulae (1) and (2):0.9≤Ca / CI≤1.,and(1)0.05≤Cb / CI≤0⁢.25.(2)

Provided are cobalt ferrite particles having a micrometer-order average particle diameter and similar particle diameters. The cobalt ferrite particles are obtained by a method for producing cobalt ferrite particles, including performing a thermal treatment on an aqueous solution containing a divalent iron salt and a divalent cobalt salt stabilized by a complexing agent (ferrite precursor).

A toner includes toner particles. A cohesion cluster containing fine silica particles and a binder component is present on surfaces of the toner particles. The toner includes fatty acid metal salt particles. An arithmetic mean value of a Feret diameter of the cohesion cluster is 1,000 to 8,000 nm. A number percentage CI of toner particles having the cohesion cluster is 1 to 15 number %. Number percentages of toner particles having the cohesion cluster in the toner after treatment under ultrasonic wave conditions A and B are represented by Ca and Cb, respectively. CI, Ca, and Cb satisfy formulae (1) and (2): ultrasonic wave condition A: output frequency 30 kHz, output capacity 0.75 W, irradiation time 300 s, ultrasonic wave condition B: output frequency 30 kHz, output capacity 25 W, irradiation time 300 s0.9≤Ca / CI≤1.Formula⁢ (1)0.1≤Cb / CI≤0⁢.40.Formula⁢ (2)

A process cartridge includes a charging unit, (I) wherein the charging unit includes a conductive member, wherein the conductive member includes a conductive layer disposed on an outer surface of a support, the conductive layer has a matrix-domain structure including a matrix and a plurality of domains, the matrix contains a first rubber, the domains contain a second rubber, and (II) wherein the toner includes agglomerates containing silica fine particles and binding components on surfaces of the toner particles, and wherein a relationship of Dms<Ag is satisfied, where Dms is an arithmetic mean of distances between adjacent domains at the outer surface of the conductive roller, and Ag is an arithmetic mean of Feret diameters of the agglomerates.

An image formation apparatus may include: a first image formation unit including a storage part and configured to form a glitter developer image; and a controller. The controller may be configured to control the first image formation unit, (i) upon forming a glitter image on a medium based on predetermined print data when a remaining amount of a glitter developer in the storage part is a first remaining amount, to form the glitter developer image with a ratio of the glitter image per unit area being a first area ratio, and (ii) upon forming the glitter image on the medium based on the predetermined print data when the remaining amount is a second remaining amount less than the first remaining amount, to form the glitter developer image with the ratio of the glitter image per unit area being a second area ratio greater than the first area ratio.

To provide a toner which is excellent in low temperature fixability and heat resistant storage property.SOLUTION: A toner contains toner particles. The toner particles have toner base particles. The toner base particles contain a binder resin. The binder resin contains a polyester resin. The toner base particles have a porous structure. A volume median diameter of the toner base particles is 6.0 μm or more and 8.0 μm or less. A BET specific surface area of the toner base particles is 1.1 m2 / g or more and 1.4 m2 / g or less.SELECTED DRAWING: Figure 1

To provide an electrophotographic apparatus and a process cartridge each suppressing the occurrence of image smearing in an output image under a high-temperature and high-humidity environment, provided are the following electrophotographic apparatus and process cartridge. That is, provided are an electrophotographic apparatus including: an electrophotographic photosensitive member; a charging unit; an image exposing unit; a developing unit; and a transferring unit, wherein the electrophotographic photosensitive member includes a surface layer containing indium tin oxide particles and a (meth)acrylic resin, and wherein the toner contains strontium titanate particles as an external additive, and a process cartridge.

A toner is provided, which has a toner particle including a binder resin and inorganic fine particles, wherein the binder resin includes a crystalline vinyl resin having a specific monomer unit having at least two long-chain alkyl groups, the content of the specific monomer unit is at least 5.0% by mass, based on the mass of the crystalline vinyl resin, the inorganic fine particles each have on a surface thereof alkyl groups, and the content of the inorganic fine particles is 0.10% by mass to 15.00% by mass, based on the mass of the toner particle.

To provide an electrostatic charge image developing toner which can form an image less likely to cause adhesion due to charging caused by contact with each component of an image forming apparatus, has high low-temperature fixability, and is less likely to cause hot offset.SOLUTION: An electrostatic charge image developing toner includes a binder resin in a toner base particle. The binder resin includes a polymer having a constituent unit represented by general formula (1) in the figure and a constituent unit represented by a specific formula). In general formula (1), R1 represents a hydrogen atom or a methyl group, and R2 represents a hydrocarbon group with an alicyclic structure in which the number of carbon atoms is from 6 to 12 inclusive.SELECTED DRAWING: Figure 1

A fine particle of a silicon polymer, wherein the fine particle has pores; the total pore volume of the fine particle is 0.35 to 1.00 cm3 / g; a number-average primary particle diameter of the fine particle is 0.05 to 0.30 μm; the silicon polymer has a siloxane bond and an Si—R1 bond; R1 represents an alkyl group having 1 to 6 carbon atoms; and designating, with reference to a chart obtained by 29Si-NMR measurement of the fine particle, A as a total peak area corresponding to the silicon polymer, and B as a peak area corresponding to Si—R1, A and B satisfy a following formula (1):10.0≤B / A×100≤45.0  (1).

Provided is a toner that includes a toner particle containing a binder resin; and an external additive, wherein the binder resin contains a polyester resin A; when a content of the polyester resin A in the binder resin is taken as Wp (mass %), Wp is 50 mass % or more; when a content ratio of the monomer unit Uiso corresponding to isophthalic acid to all monomer units corresponding to polycarboxylic acids in the polyester resin A is taken as MIPA (mol %), MIPA is 40 mol % or more; the external additive contains inorganic fine powder; and the inorganic fine powder contains a silica fine particle having aluminum hydroxide on the surface thereof.

A toner comprising a toner particle comprising a binder resin, wherein the binder resin comprises a first resin and a second resin, the first resin is a crystalline resin, the second resin is an amorphous resin, and in observations of cross sections of 100 toner particles using a transmission electron microscope, (i) when an area ratio A (area %) denotes a ratio of an area occupied by the first resin in each of cross sections of the toner particles, an average value of the area ratio A is 30 to 75 area %, and (ii) when X denotes the number of cross sections of the toner particle for which the area ratio A is 90 area % or more and Z denotes the total number of cross sections of observed toner particles, then a value of X / Z is 0.15 or more.

A toner comprising a toner particle comprising a binder resin and a release agent, wherein the binder resin comprises a first resin and a second resin; the first resin is a crystalline resin having a melting point Tp of 50° C. to 90° C.; the second resin is an amorphous resin; in a cross section of the toner particle observed by a transmission electron microscope, the cross section of the toner particle has a matrix-domain structure composed of a matrix comprising the first resin and domains comprising the second resin; an area ratio of the matrix comprising the first resin in a total area of the cross section of the toner particle is 35 to 70 area %; and where a longest direction of each of the domains is taken as a longitudinal direction, a standard deviation of an angle of the longitudinal direction of the domains is 25° or less.

A toner comprising a toner particle containing a binder resin and an inorganic fine particle, wherein the binder resin contains a crystalline resin, the crystalline resin has a first monomer unit represented by the following formula (1), the inorganic fine particle is at least one inorganic fine particle selected from the group consisting of a particle containing CaCO3, a particle containing BaSO4, a particle containing Mg3Si4O10(OH)2, and a particle containing Al2Si2O5(OH)4, the inorganic fine particle is treated with a fatty acid, and a content B of the inorganic fine particle in the toner particle is 1.0 mass % or more to 15.0 mass % or less,wherein RZ1 represents a hydrogen atom or a methyl group, and R1 represents an alkyl group having 18 to 36 carbon atoms.

To provide an image forming system that can obtain a satisfactory image for a long period without causing toner filming on a surface of a photoreceptor.SOLUTION: An electrophotographic image forming system includes the steps of: forming an electrostatic latent image at least on a photoreceptor; performing development by using a toner for electrostatic charge image development; and bringing a leading end ridge part of a cleaning blade into pressure contact with a surface of the photoreceptor to remove the toner for electrostatic charge image development. A surface layer of the photoreceptor contains a thermoplastic resin having at least electron acceptability. Toner particles constituting the toner for electrostatic charge image development each contain at least a fatty acid metal salt in its surface as an external additive. A leading end ridge part of a cleaning blade having an edge angle within a range of 90-130° is brought into pressure contact with a surface of the photoreceptor, and the effective contact angle of the cleaning blade is within a range of 7-20°.SELECTED DRAWING: Figure 3

A toner containing a toner particle containing a binder resin and a wax, wherein the binder resin contains a crystalline resin, the content of the crystalline resin is within a specific range, in viscoelastic measurement of the toner, when a storage elastic modulus of the toner at a temperature T (° C.) is G′(T), in a graph in which a horizontal axis represents the temperature T, and a vertical axis represents a value d(log G′(T)) / dT obtained by differentiating Log G′(T) with respect to the temperature T, the local minimum value is observed in a specific range, when a temperature at which the local minimum value is reached is defined as a temperature T1 (° C.), d(log G′(T1)) / dT, d(log G′(T1+3)) / dT≤0, G′(T1), and G′(T1+30) satisfy specific relationships.

An external additive for toner, wherein the external additive is an organosilicon polymer particle, and defining A (nm) as the number-average particle diameter of primary particles of the external additive measured using a scanning electron microscope, and defining B (nm) as the number-average particle diameter of the external additive measured in accordance with a centrifugal sedimentation method, the A and the B satisfy a following Expression (1):1.5≤B / A≤3.0  (1).

An image forming apparatus may include a holding container that holds a toner containing an antibacterial agent, and an image forming unit that forms an antibacterial region by applying the toner supplied from the holding container to a recording material by performing an image forming process. The antibacterial region is formed on a partial region that is a partial region of a first surface of the recording material and that is likely to be touched by a user's finger

Mixtures are disclosed containing a plurality of charged pigment particles and a one or more charge control agents. At least one of the charge control agents has a chemical structure that includes a cationic head group, such as an ammonium cation or an iminium compound, and a non-ionic, polar functional group, other than an acyclic secondary amide group. The mixtures are useful as dispersions for forming electrophoretic media that may be incorporated into electrophoretic displays. Alternatively, the dispersions may be useful for forming electrophotographic toners and dispersions for other printing applications.

The present invention provides: a powder which is capable of forming an electromagnetic wave absorption layer that has electromagnetic wave absorption characteristics in a wider frequency region than ever before and is suppressed in performance variation, and which can be electrostatically adhered or heat fixed to a support body; and an electromagnetic wave absorber which comprises a melt molded body of the powder as an electromagnetic wave absorption layer. The present invention provides: a powder which is capable of forming an electromagnetic wave absorption layer that has electromagnetic wave absorption characteristics in a wider frequency region than ever before and is suppressed in performance variation, and which can be electrostatically adhered or heat fixed to a support body; and an electromagnetic wave absorber which comprises a melt molded body of the powder as an electromagnetic wave absorption layer.

A method of producing a toner, the method comprising: a melt-kneading step of melt-kneading a mixture A comprising a binder resin, and a material to be dispersed over the binder resin to yield a kneaded product, wherein the mixture A comprises 1.0 to 10.0 parts by mass of water to 100.0 parts by mass of the binder resin and the material to be dispersed in total, the water comprised in the mixture A comprises bubbles comprising ultrafine bubbles having a particle diameter of not more than 1000 nm, and the number of the ultrafine bubbles comprised in the water comprised in the mixture A is at least 1.0×104 per milliliter.

An image forming apparatus includes: a forming unit configured to form an image on a sheet by forming a plurality of toner images using a plurality of types of toner, and transfer the plurality of toner images onto the sheet, or transfer the plurality of toner images onto the sheet via an intermediate transfer member; and a controller configured to control the forming unit to form a formed image and an antimicrobial pattern on the sheet based on first image data representing the formed image, wherein at least one first toner out of the plurality of types of toner is antimicrobial toner that includes an antimicrobial agent, at least one second toner out of the plurality of types of toner is non-antimicrobial toner that does not contain the antimicrobial agent, and the antimicrobial pattern is formed using the first toner.

A fine particle of a silicon polymer having a siloxane group and a silanol group, wherein a moisture adsorption amount of the fine particle at a temperature of 30° C. and a humidity of 80% RH is from 1.0 mg / g to 22.0 mg / g, an amount of the silanol group of the fine particle measured by a titration method using KOH is from 0.012 mmol / g to 0.120 mmol / g, and a number average particle diameter of primary particle of the fine particle is from 0.05 μm to 0.30 μm.

An external additive for toner comprising a particle of a silicon polymer having a siloxane bond and a Si—O—C bond, wherein in an FT-IR spectrum of the external additive obtained by an ATR method, a maximum peak is present in a range of from 1030 cm−1 to 1070 cm−1, where an average intensity in a range of from 1015 cm−1 to 1025 cm−1 of the spectrum is denoted by A and an average intensity in a range of from 1085 cm−1 to 1095 cm−1 is denoted by B, the A and the B satisfy a following formula (1):0.5⁢5≤A / B≤1.5.(1)

Provided is a toner comprising: a toner particle containing a binder resin; and an organic silicon polymer particle on a surface of the toner particle, wherein the binder resin contains a crystalline resin, and when the toner particle is pelletized and a Young's modulus of the toner measured in a micro compression test at 25° C. is represented by TE (MPa) and when one organic silicon polymer particle is separated from the toner and a Young's modulus of the one organic silicon polymer particle measured in a micro compression test at 25° C. is represented by SiE (MPa), TE and SiE satisfies 800≤TE≤2500 and 1.5≤SiE / TE≤10.0.

A toner including: a toner particle; and an inorganic fine particle, wherein the inorganic fine particle contains a strontium titanate fine particle, a Si-containing protrusion portion is present at a surface of the strontium titanate fine particle, and the toner contains an amorphous polyester resin and an aluminum element at a surface of the toner particle.