G03G9/097

TONER FOR ELECTROSTATIC IMAGE DEVELOPMENT, ELECTROSTATIC IMAGE DEVELOPER, AND TONER CARTRIDGE

A toner for electrostatic image development contains: toner base particles containing at least a nonionic surfactant, a binder resin, and a release agent; and an external additive. The content of the nonionic surfactant is from 0.05% by mass to 1% by mass inclusive based on the total mass of the toner, and the external additive contains tin oxide particles.

ELECTROSTATIC CHARGE IMAGE DEVELOPING TONER, ELECTROSTATIC CHARGE IMAGE DEVELOPER, TONER CARTRIDGE, PROCESS CARTRIDGE, IMAGE FORMING APPARATUS, AND IMAGE FORMING METHOD

An electrostatic charge image developing toner includes: toner particles including an amorphous resin and a crystalline polyester resin including a polycondensate of a linear dicarboxylic acid and a linear dialcohol having 2 to 12 carbon atoms; and an external additive including silica particles having a BET specific surface area of 100 m.sup.2/g or more. The electrostatic charge image developing toner satisfies the expression: 0.05H2/H10.95, wherein H1 (mW/g) is an endothermic energy amount based on an endothermic peak derived from the crystalline polyester resin in a first temperature increase process in differential scanning calorimetry according to ASTM D3418-8 (2008), and H2 (mW/g) is an endothermic energy amount based on an endothermic peak derived from the crystalline polyester resin in a second temperature increase process in differential scanning calorimetry according to ASTM D3418-8 (2008).

Toner

A toner comprising: a toner particle that contains a binder resin and a colorant: and an external additive, wherein (1) the average circularity of the toner is at least 0.960; (2) the fixing ratio of the external additive on the toner particle is from 75% to 100%; and (3) in a differential curve obtained by the differentiation, by load, of a load-displacement curve where the horizontal axis is load (mN) and the vertical axis is displacement (m), the load-displacement curve being provided by measurement of the strength of the toner by a nanoindentation procedure, a load A that provides a maximum value in the differential curve in a load region from 0.20 mN to 2.30 mN is from 1.15 mN to 1.50 mN.

ELECTROSTATIC-IMAGE DEVELOPING TONER, ELECTROSTATIC-IMAGE DEVELOPER, AND TONER CARTRIDGE

An electrostatic-image developing toner includes toner particles including a binder resin including an amorphous resin including a polyester resin segment and a styrene acrylate resin segment and a release agent. The content of 5-chloro-3-hydroxy-2-methoxy-2-naphthanilide in the electrostatic-image developing toner is 1,000 ppm by mass or less.

TONER FOR DEVELOPING ELECTROSTATIC CHARGE IMAGE
20200292952 · 2020-09-17 ·

A toner for electrostatic charge image development is a toner for electrostatic charge image development including toner particles containing a binder resin and an external additive, wherein the binder resin contains a crystalline polyester resin and an amorphous polyester resin, the external additive includes AlSi composite oxide particles, and a Si element content of the AlSi composite oxide particles is in the range of 50 to 90 mass % and a Si element ratio on surfaces of the AlSi composite oxide particles is in the range of 3 to 35 at %.

ELECTROPHOTOGRAPHIC IMAGE FORMING APPARATUS AND PROCESS CARTRIDGE

Provided are an electrophotographic apparatus and a process cartridge each capable of suppressing the occurrence of a black spot (white background contamination) in an output image under a low-temperature and low-humidity environment. The electrophotographic apparatus includes: an electrophotographic photosensitive member including a support, a photosensitive layer, and a protective layer in the stated order; an exposing device; a developing device; and a cleaning device, wherein the protective layer has a triarylamine structure and a specific structure at a ratio in a specific range, and a toner contains toner particles each containing at least a resin, and an external additive. The toner has a volume-average particle diameter of 7 m or more. The external additive contains a compound containing a titanium atom. The ratio of the mass of the compound containing a titanium atom to the total mass of the toner is 0.6 mass % or more.

TONER
20200292956 · 2020-09-17 ·

A toner comprising: a toner particle; and an external additive, wherein the external additive includes spherical silica particles and hydrotalcite particles, a number average particle diameter Da of the spherical silica particles is from 10 nm to 40 nm, a circularity of the spherical silica particles is at least 0.80, and the toner satisfies formula (1) below:


{Ga(1Ka/100)}/{Gb(1Kb/100)}0.050(1) wherein Ga: a content of the spherical silica particles with respect to 100 parts by mass of the toner particle; Gb: a content of the hydrotalcite particles with respect to 100 parts by mass of the toner particle; Ka: a fixing ratio (%) of the spherical silica particles on a surface of the toner particle; and Kb: a fixing ratio (%) of the hydrotalcite particles on the surface of the toner particle.

TONER FOR DEVELOPING ELECTROSTATIC CHARGE IMAGE, ELECTROSTATIC CHARGE IMAGE DEVELOPER, AND TONER CARTRIDGE

A toner for developing an electrostatic charge image includes toner particles containing a binder resin; and an external additive containing silica particles, in which a coefficient of variation of a Si content is determined by determining the Si content in 0.5 m0.5 m square regions in a surface of each of the toner particles after performing a process of dispersing the toner in water and drying the dispersed toner, and an amount of change between this coefficient of variation of the Si content and a coefficient of variation of a Si content before the process ((coefficient of variation of Si content after process)(coefficient of variation of Si content before process)) is 0.05 or more and 0.60 or less.

TONER FOR DEVELOPING ELECTROSTATIC CHARGE IMAGE, ELECTROSTATIC CHARGE IMAGE DEVELOPER, AND TONER CARTRIDGE

A toner for developing an electrostatic charge image includes toner particles containing a binder resin; and an external additive containing silica particles, in which a coefficient of variation of a Si content is determined by determining the Si content in 0.5 m0.5 m square regions in a surface of each of the toner particles after performing a process of dispersing the toner in water and drying the dispersed toner, and an amount of change between this coefficient of variation of the Si content and a coefficient of variation of a Si content before the process ((coefficient of variation of Si content after process)(coefficient of variation of Si content before process)) is 0.05 or more and 0.60 or less.

TONER

A toner comprising: a toner particle that contains a release agent-containing toner base particle, and an organosilicon polymer on a toner base particle surface, and an external additive A, the organosilicon polymer has a T3 unit structure; the organosilicon polymer forms protruded portions on the toner base particle surface; the number-average value of the protrusion height H is from 30 nm to 300 nm; the ratio of the number-average primary particle diameter R of the external additive A to the number-average value of the protrusion height H is from 1.00 to 4.00; the number-average primary particle diameter R of the external additive A is from 30 nm to 1,200 nm; and, in an image obtained by observing the toner surface with SEM, the area percentage for the bright region area in the image with reference to the total area of the image is from 30.0% to 75.0%.