G03G9/0836

MAGNETIC TONER

A magnetic toner comprising a toner particle comprising a binder resin and a magnetic body, wherein the binder resin comprises a styrene-acrylic resin, the styrene-acrylic resin comprises a monomer unit represented by Formula (1):

##STR00001## where, in Formula (1), R.sup.1 represents a hydrogen atom or a methyl group; and R.sup.2 represents a linear alkyl group having C.sub.B carbon atoms, C.sub.B being an integer from 10 to 15; the magnetic body comprises an alkyl group having C.sub.M carbon atoms, on a surface of the magnetic body, C.sub.M being an integer from 4 to 20; C.sub.B and C.sub.M satisfy Formula (3):


|C.sub.M−C.sub.B|≤10  (3), and in a cross-sectional observation of the magnetic toner using a transmission electron microscope, a coefficient of variation of an occupied area ratio of the magnetic body in a specific square grid, is 80.0% or lower.

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

An electrostatic charge image developing carrier includes a magnetic particle and a coating resin layer that covers the magnetic particle and contains a silica particle, and a ratio of Si on a surface of the coating resin layer, determined by an X-ray photoelectron spectroscopy (XPS), is 6 atom % or more and 12 atom % or less.

TONER
20220171303 · 2022-06-02 ·

There is provided a toner containing: a toner particle containing a binder resin, a releasing agent, and a colorant; and an iron oxide particle present on a surface of the toner particle, in which the iron oxide particle has a surface containing a compound having a specific structure.

CARRIER FOR DEVELOPING ELECTROSTATIC CHARGE IMAGE, ELECTROSTATIC CHARGE IMAGE DEVELOPER, PROCESS CARTRIDGE, IMAGE FORMING APPARATUS, IMAGE FORMING METHOD, AND METHOD FOR PRODUCING CARRIER FOR DEVELOPING ELECTROSTATIC CHARGE IMAGE

A carrier for developing an electrostatic charge image includes magnetic particles and a coating layer covering the magnetic particles, the coating layer containing a resin and inorganic particles. The percentage exposure of the magnetic particles on the surface is 50% or more and 80% or less, and the mean width RSm and the maximum height Rz of the roughness profile on the surface are 0.9 μm or more and 1.5 μm or less and 2.0 μm or more and 6.0 μm or less, respectively.

Toner

A toner comprising a toner particle including a binder resin and a magnetic body, wherein in cross-sectional observation of the toner with a transmission electron microscope, where an area percentage occupied by the magnetic body in a region of 200 nm or less from a contour of a cross section of the toner particle to a centroid of the cross section is taken as A1, and an area percentage occupied by the magnetic body in a region of from 200 nm to 400 nm from the contour of the cross section of the toner particle to the centroid of the cross section is taken as A2, the area percentage A1 is from 38% to 85%, the area percentage A2 is from 0% to 37%, and a ratio A2/A1 of the area percentage A2 to the area percentage A1 is from 0 to 0.75.

Magnetic toner

A magnetic toner comprising a magnetic toner particle including a binder resin, a magnetic body and a crystalline polyester, wherein in cross-sectional observation of the magnetic toner particle using a transmission electron microscope, a variation coefficient CV3 of an occupied area ratio of the magnetic body when a cross section of the magnetic toner particle is divided by a square grid having a side of 0.8 μm is from 40.0% to 80.0%, and assuming that a storage elastic modulus at 40° C. is taken as E′(40) [Pa] and a storage elastic modulus at 85° C. is taken as E′(85) [Pa], the storage elastic moduli being obtained in a powder dynamic viscoelasticity measurement of the magnetic toner, the following formulas (1) and (2) are satisfied.
E′(85)≤2.0×10.sup.9  (1)
[E′(40)−E′(85)]×100/E′(40)≥70  (2)

MAGNETIC TONER

A magnetic toner comprising a toner particle comprising a binder resin and magnetic iron oxide particles, wherein a content of the magnetic iron oxide particles in the magnetic toner is 30 to 45 mass %, the magnetic iron oxide particles contain (i) spherical magnetic iron oxide particles and (ii) at least one selected from the group consisting of hexahedral magnetic iron oxide particles and octahedral magnetic iron oxide particles, and a content of the spherical magnetic iron oxide particles in the magnetic iron oxide particles is 1.0 to 9.0% by number.

MAGNETIC TONER
20210255557 · 2021-08-19 ·

A magnetic toner comprising a magnetic toner particle including a binder resin, a magnetic body and a crystalline polyester, wherein in cross-sectional observation of the magnetic toner particle using a transmission electron microscope, a variation coefficient CV3 of an occupied area ratio of the magnetic body when a cross section of the magnetic toner particle is divided by a square grid having a side of 0.8 μm is from 40.0% to 80.0%, and assuming that a storage elastic modulus at 40° C. is taken as E′(40) [Pa] and a storage elastic modulus at 85° C. is taken as E′(85) [Pa], the storage elastic moduli being obtained in a powder dynamic viscoelasticity measurement of the magnetic toner, the following formulas (1) and (2) are satisfied.


E′(85)≤2.0×10.sup.9  (1)


[E′(40)−E′(85)]×100/E′(40)≥70  (2)

Magnetic toner and method for manufacturing magnetic toner

Provided is a magnetic toner having a toner particle containing a binder resin and a magnetic body, wherein the binder resin contains a polymer A having a first monomer unit and a second monomer unit, the first polymerizable monomer is at least one selected from the group consisting of the (meth)acrylic acid esters having C.sub.18-36 alkyl groups, a content of the first monomer unit and a content of the second monomer unit based on the total moles of all monomer units in the polymer A are respectively 5.0 to 60.0 mol % and 20.0 to 95.0 mol %, and assuming that an SP value of the first monomer unit and the second monomer unit are taken as SP.sub.11 (J/cm.sup.3).sup.0.5 and SP.sub.21(J/cm.sup.3).sup.0.5, respectively, 3.00≤(SP.sub.21−SP.sub.11)≤25.00 is satisfied, and an oil absorption of the magnetic body is 5 to 40 ml/100 g.

TONER

A toner comprising a toner particle comprising a magnetic body, and a silica fine particle on a surface of the toner particle, wherein fragment ions corresponding to a D unit structure are observed in a specific measurement; when the silica fine particle is dispersed in a mixed solution of ethanol and aqueous solution of NaCl, followed by a titration operation using sodium hydroxide, a titer is within a specific range; in a chemical shift obtained by a specific measurement, with D as an area of a peak having a peak top present in a range from 25 to 15 ppm, and with D1 as an area of a peak having a peak top present in a range of more than 19 ppm and 17 ppm or less, D and D1 are in a specific ratio; and the magnetic body is present on the surface of the toner particle.