G03G9/081

METHOD FOR MANUFACTURING TONER FOR ELECTROSTATIC CHARGE IMAGE DEVELOPMENT
20220066336 · 2022-03-03 · ·

The preset invention provides a method for producing a toner for electrostatic-image development comprising: a dispersing step of performing a dispersing treatment in which a cavitation effect is obtained on a color resin particle containing a binder resin, a colorant, a charge control agent, and a release agent in an aqueous dispersion median so as to obtain a dispersion of the color resin particle; and a heating step of performing a heat treatment on the dispersion of the color resin particle at a temperature of equal to or more than a glass transition temperature of the color resin particle and 95° C. or less for a heating time of 5 minutes or more and 10 hours or less.

Magnetic core material for electrophotographic developer, carrier for electrophotographic developer, developer, method for producing magnetic core material for electrophotographic developer, method for producing carrier for electrophotographic developer, and method for producing developer
11099495 · 2021-08-24 · ·

To provide a magnetic core material and carrier for electrophotographic developer, which have small environmental dependence of the electric resistance, can suppress the carrier scattering, and can stably provide good images; a developer contains the carrier; and methods for producing them. The magnetic core material satisfying a value of Formula (1): a+b×10+c+d+e+f, being from 20 to 150, when a fluoride ion amount is denoted by a (ppm), a chloride ion amount is denoted by b (ppm), a bromide ion amount is denoted by c (ppm), a nitrite ion amount is denoted by d (ppm), a nitrate ion amount is denoted by e (ppm), and a sulfate ion amount is denoted by f (ppm), which are measured by a combustion ion chromatography method.

RESIN FINE PARTICLE, THERMOPLASTIC RESIN PARTICLE, AND METHOD FOR PRODUCING RESIN FINE PARTICLE

A resin fine particle includes a polyester resin; and a basic dye, in which an volume average particle diameter of the resin fine particle is 0.05 μm or more and 1 μm or less, and a ratio of a concentration of the basic dye in a center of gravity portion of the resin fine particle to a concentration of the basic dye in a surface layer portion having a depth of 10 nm or less from a surface of the resin fine particle is 0.8 or more.

Toner

A toner including a toner particle that contains a binder resin, and an inorganic fine particle, wherein the inorganic fine particle contains aggregated particles; the aggregated particles contain primary particles of at least one metal salt selected from the group consisting of titanate metal salts and zirconate metal salts; the primary particles have a number-average particle diameter of from 15 nm to 55 nm; the aggregated particles have an aggregation diameter of from 80 nm to 300 nm, the aggregated particles have a volume resistivity of from 2×10.sup.9 Ω.Math.cm to 2×10.sup.13 Ω.Math.cm; and the aggregated particles cover a surface of the toner particle, and a coverage ratio of the aggregated particles with respect to the surface of the toner particle is from 0.3 area % to 10.0 area %.

Toner and toner manufacturing method

A toner comprising a toner particle containing a binder resin, the storage elastic modulus Gt′ (150) of the toner at 150° C. is at least 1.0×10.sup.4 Pa, the binder resin contains a polymer A having a first monomer unit derived from a first polymerizable monomer and a second monomer unit derived from a second polymerizable monomer different from the first polymerizable monomer, the first polymerizable monomer is selected from specific (meth)acrylic acid esters, the contents of the first monomer unit and second monomer unit in the polymer A are within specific ranges, and the SP values of the first monomer unit and second monomer unit are within specific ranges.

MAGENTA TONER, DEVELOPER, TONER ACCOMMODATING UNIT, IMAGE FORMING APPARATUS, AND IMAGE FORMING METHOD

A magenta toner is provided. The magenta toner comprises toner particles each comprising a binder resin and a colorant. From 1.0% to 25.0% by number of the toner particles have a CH rate of 25.0% or more in absolute value. The CH rate is calculated from the following formula (1):


CH rate (%)=[(I.sub.n−I.sub.ave)/I.sub.ave]×100  Formula (1)

where, in a Raman spectrum of each toner particle, I.sub.n represents an integrated intensity within a wavenumber region of from 2,750 to 3,250 cm.sup.−1 when an intensity at a wavenumber λ within a wavenumber region of from 1,200 to 3,250 cm.sup.−1 is s normalized to 1, where a total intensity of all the toner particles is maximum at the wavenumber λ; and I.sub.ave represents an average of the I.sub.n.

TONER AND TONER MANUFACTURING METHOD
20210286280 · 2021-09-16 ·

A toner contains toner particles. The toner particles have an average circularity of 0.900 to 0.950. The toner particles have an arithmetic average surface roughness value of 30 to 100 nm. A ratio of a surface roughness standard deviation of the toner particles to the arithmetic average value is 0.3 or lower. The arithmetic average value of surface roughness of the toner particles is preferably 30 to 50 nm.

TONER AND METHOD FOR PRODUCING TONER
20210278774 · 2021-09-09 ·

A toner comprising a toner particle comprising a binder resin and a wax, wherein the binder resin comprises an amorphous polyester resin and a polymer A, contents of the amorphous polyester resin and the polymer A in the binder resin are within specific ranges, the polymer A comprises a first monomer unit in which ester (meth)acrylates comprising 18 to 36 carbon atoms are polymerized, a content ratio of the first monomer unit in the polymer A is within specific range, the toner comprises a matrix-domain structure comprising a matrix comprising the amorphous polyester resin and domains, and the domains comprise a domain A comprising at least 80 mass % of the polymer A and a domain B comprising at least 80 mass % of the wax.

TONER AND METHOD FOR MANUFACTURING TONER
20210181649 · 2021-06-17 ·

A toner is provided, which has a toner particle containing a binder resin including a first resin and a second resin, wherein the first resin is a crystalline resin, the second resin is an amorphous resin, the first resin contains a specific amount of a first monomer unit having a specific structure, an acid value of the first resin and an acid value of the second resin are within specific ranges, a domain-matrix structure formed of a matrix containing the first resin and domains containing the second resin appears in cross-sectional observation of the toner, the toner particle contains a multivalent metal element, the multivalent metal element is at least one metal element selected from the group consisting of Mg, Ca, Al, Fe and Zn, and a total content of the multivalent metal element is within a specific range.

White toner and method for producing same

A white toner comprising a toner particle including a binder resin, an inorganic white pigment, and a polyvalent metal salt compound, wherein the inorganic white pigment has an acidic group at a surface thereof; an amount of the inorganic white pigment in the toner particle is 10% to 50% by volume; the polyvalent metal salt compound is a specific compound; an absolute value of the difference between an SP value (J/cm.sup.3).sup.1/2 of the binder resin and that of the polyvalent metal salt compound is 0.0 to 6.0; and an amount of the polyvalent metal salt compound, an amount of a polyvalent metal, the amount of the inorganic white pigment, and an amount of the acidic group at a surface of the inorganic white pigment satisfy a specific relationship.