US Pat. No. 9,557,682

RESIN-COATED CARRIER FOR ELECTROPHOTOGRAPHIC DEVELOPER AND ELECTROPHOTOGRAPHIC DEVELOPER USING THE RESIN-COATED CARRIER

POWDERTECH CO., LTD., Ch...

1. A resin-coated carrier for an electrophotographic developer, wherein the carrier has a coated resin layer on the surface
of a porous ferrite core material, and
the pore volume and the peak pore size of the porous ferrite core material are 55 to 160 mm3/g and 0.2 to 0.7 ?m, respectively, and wherein

the pores of the porous ferrite core material are not impregnated with a resin.

US Pat. No. 9,372,426

FERRITE PARTICLE HAVING OUTER SHELL STRUCTURE, FERRITE CARRIER CORE MATERIAL FOR ELECTROPHOTOGRAPHIC DEVELOPER, AND ELECTROPHOTOGRAPHIC DEVELOPER

POWDERTECH CO., LTD., Ch...

1. A ferrite carrier core material for an electrophotographic developer comprising a ferrite particle, wherein
the ferrite particle consists of a porous structure of ferrite in an interior, and an outer shell structure of ferrite having
a higher density than the interior, on an outer periphery.

US Pat. No. 9,201,329

POROUS FERRITE CORE MATERIAL FOR ELECTROPHOTOGRAPHIC DEVELOPER, RESIN-COATED FERRITE CARRIER AND ELECTROPHOTOGRAPHIC DEVELOPER USING THE FERRITE CARRIER

POWDERTECH CO., LTD., Ch...

1. A porous ferrite core material for an electrophotographic developer comprising:
Mn in an amount of 10 to 25% by weight; Mg in an amount of 0.2 to 3% by weight; Fe in an amount of 48 to 60% by weight; and
Sr in an amount of 0.14 to 1% by weight; wherein the porous ferrite core material is formed under conditions that result in
an apparent density of 1.5 to 1.9 g/cm3, a shape factor SF-2 of 101 to 110, and a magnetization as measured with a VSM at 1K·1000/4?·A/m of 40 to 60 Am2/kg.

US Pat. No. 9,201,328

CORE MATERIAL FOR RESIN-FILLED FERRITE CARRIER AND FERRITE CARRIER FOR ELECTROPHOTOGRAPHIC DEVELOPER, AND ELECTROPHOTOGRAPHIC DEVELOPER USING THE FERRITE CARRIER

POWDERTECH CO., LTD., Ch...

1. A resin-filled ferrite carrier core material for an electrophotographic developer, comprising a porous ferrite particle
having an average compression strength of 100 mN or more and a coefficient of variation of the compression strength of 50%
or less.

US Pat. No. 10,564,561

FERRITE CARRIER CORE MATERIAL FOR ELECTROPHOTOGRAPHIC DEVELOPER, FERRITE CARRIER FOR ELECTROPHOTOGRAPHIC DEVELOPER, ELECTROPHOTOGRAPHIC DEVELOPER, AND METHOD FOR MANUFACTURING FERRITE CARRIER CORE MATERIAL FOR ELECTROPHOTOGRAPHIC DEVELOPER

POWDERTECH CO., LTD., Ch...

1. A ferrite carrier core material for an electrophotographic developer, comprising a ferrite particle containing:15 mass % or more and 25 mass % or less of Mn,
0.5 mass % or more and 5.0 mass % or less of Mg,
0.05 mass % or more and 4.0 mass % of Sr, and
45 mass % or more and 55 mass % or less of Fe,
with Zr localized in the surface thereof;
wherein the ferrite carrier core material has a Cl concentration of 0.1 ppm or more and 50 ppm or less in a Cl elution testing of the ferrite carrier core material, the Cl elution testing being performed by:
(a) consecutively adding to a 150 ml glass bottle:
50.000 g±0.0002 g of the ferrite carrier core material,
50 ml of a phthalate (pH: 4.01), and
1 ml of an ionic strength conditioner;
(b) closing the glass bottle and shaking the glass bottle on a paint shaker for 10 minutes to obtain a mixture;
(c) applying a magnet to the bottom of the glass bottle, and filtering the mixture into a 50 ml vessel made of PP through filter paper No. 5B to obtain a supernatant,
(d) measuring the voltage of the supernatant with a pH meter, and
(e) comparing the measured voltage to a calibration curve of voltages measured from pure water and solutions having Cl concentrations of 1 ppm, 10 ppm, 100 ppm, and 1000 to calculate the Cl concentration of the ferrite carrier core material.
US Pat. No. 9,081,318

FERRITE CARRIER CORE MATERIAL AND FERRITE CARRIER FOR ELECTROPHOTOGRAPHIC DEVELOPER, METHODS FOR MANUFACTURING THESE, AND ELECTROGRAPHIC DEVELOPER USING THE FERRITE CARRIER

POWDERTECH CO., LTD., Ch...

6. A ferrite carrier for an electrophotographic developer, wherein a surface of a ferrite carrier core material according
to claim 1 is coated with a resin.
US Pat. No. 9,329,515

RESIN-COATED CARRIER FOR ELECTROPHOTOGRAPHIC DEVELOPER AND ELECTROPHOTOGRAPHIC DEVELOPER USING THE RESIN-COATED CARRIER

POWDERTECH CO., LTD., Ch...

1. A resin-coated carrier for an electrophotographic developer, wherein the surface of a magnetic particle is coated with
a mixed resin composed of two resins, and when the two resins are denoted by the resin 1 and the resin 2, respectively, the relative difference between the respective adsorbed moisture amounts of the resin 1 and the resin 2 at a temperature of 30° C. and a relative humidity of 80% satisfies the following formula (1):
1?|ax?b(100?x)|?10  (1)

a: the adsorbed moisture content (% by weight) of the resin 1
b: the adsorbed moisture content (% by weight) of the resin 2
x: the content percentage of the resin 1 (0
US Pat. No. 9,588,453

RESIN-FILLED FERRITE CARRIER FOR ELECTROPHOTOGRAPHIC DEVELOPER AND ELECTROPHOTOGRAPHIC DEVELOPER USING THE FERRITE CARRIER

POWDERTECH CO., LTD., Ka...

1. A resin-filled ferrite carrier for an electrophotographic developer, in which a void of a porous ferrite particle used
as a ferrite carrier core material is filled with silicone resin,
wherein a true specific gravity (Y) of the porous ferrite particle filled with the silicone resin and a Si/Fe value (X) measured
by fluorescent X-ray elemental analysis satisfy the following inequality (1):

?350X?Y?4.83??100X  (1); and

wherein the true specific gravity (Y) of the porous ferrite particle filled with the silicone resin also satisfies the following
inequality (2):

4.15 g/cm3?Y  (2).

US Pat. No. 10,036,982

CARRIER AND ELECTROPHOTOGRAPHIC DEVELOPER USING THE CARRIER

POWDERTECH CO., LTD., Ch...

1. A carrier comprising a core material coated with a resin, the core material comprisinga magnetic component, the magnetic component being porous ferrite particles having voids, and wherein the voids are filled with
a nonmagnetic component
filling the voids of the porous ferrite particles;
being a cured product of a silane coupling agent or a methyl silicone oligomer, and
filling the voids of the porous ferrite particles;
wherein the carrier contains volatile organic compounds which evaporate by heating at 60° C. for 2 hours, and
the sum total of the volatile organic compounds in the carrier, which is defined as a sum total of the total evaporation amount of non-aldehyde components subjected to quantitative analysis with a gas chromatograph-mass spectrometer and the total evaporation amount of aldehyde components measured by high performance liquid chromatography is 1 ppb or more and 1.5 ppm or less;
the silane coupling agent being any of 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, and 3-methacryloxypropyltriethoxysilane.

US Pat. No. 10,603,614

FERRITE PARTICLES HAVING OUTER SHELL STRUCTURE USED FOR FILTERING MEDIUM

POWDERTECH CO., LTD., Ch...

1. A particle comprising a core and an outer shell, the outer shell comprising a titanium oxide, and the core comprising ferrite;wherein an apparent density of the core is smaller than an apparent density of the outer shell.
US Pat. No. 10,593,454

SPHERICAL FERRITE PARTICLES IN NANO-SIZE AND METHOD OF MANUFACTURING SAME

POWDERTECH CO., LTD., Ch...

1. A manganese-magnesium ferrite particle comprising:from 13 to 25% by weight manganese,
from 1 to 3.5% by weight magnesium, and from 43 to 57% by weight iron, as the manganese-magnesium ferrite;
the particle having an average particle size of 1 to 2000 nm and a spherical shape; and
the particle being surface-treated with an aluminum-compound.

US Pat. No. 11,032,955

FERRITE POWDER, RESIN COMPOSITION, ELECTROMAGNETIC SHIELDING MATERIAL, ELECTRONIC CIRCUIT SUBSTRATE, ELECTRONIC CIRCUIT COMPONENT, AND ELECTRONIC DEVICE HOUSING

POWDERTECH CO., LTD., Ch...

1. A powdered ferrite comprising platy ferrite particles having a spinel crystal structure,wherein the powdered ferrite comprises at least 50 number % platy ferrite particles each having at least one protrusion on a surface of the particle, and the at least one protrusion has a shape selected from the group consisting of a rectangular pyramid, a truncated rectangular pyramid, an elongated rectangular pyramid, and combinations thereof.
US Pat. No. 10,501,333

SPHERICAL FERRITE POWDER, RESIN COMPOUND INCLUDING SPHERICAL FERRITE POWDER, AND MOLDED PRODUCT MADE OF RESIN COMPOUND

POWDERTECH CO., LTD., Ch...

1. A spherical ferrite powder comprising a mixture of:spherical ferrite particles having a particle diameter of less than 11 ?m; and
spherical ferrite particles having a particle diameter of 11 ?m or more;
wherein:
the spherical ferrite particles having a particle diameter of less than 11 ?m have a BET specific surface area of 2 to 50 m2/g;
the spherical ferrite particles having a particle diameter of 11 ?m or more have a BET specific surface area of 0.1 to 2 m2/g;
an amount of the spherical ferrite particles having a particle diameter of less than 11 ?m present in the mixture is 15 to 30 wt % of a total weight of the mixture; and
a volume average particle diameter of the mixture of spherical ferrite particles is 10 to 50 ?m.

US Pat. No. 10,585,369

FERRITE PARTICLE HAVING OUTER SHELL STRUCTURE

POWDERTECH CO., LTD., Ch...

1. A ferrite particle comprising a porous core and an outer shell, the porous core comprising calcined ferrite and the outer shell comprising a Ti oxide, the ferrite particle comprising:a) 0.5 wt % to 4 wt % Mg,
b) 3 wt % to 20 wt % Mn,
c) 47 wt % to 70 wt % Fe, and
d) 0.5 wt % to 4.5 wt % Ti;
wherein the porous core is coated with particles of a Ti oxide to obtain a Ti oxide-coated porous core and Ti oxide-coated porous core is then fired to obtain the ferrite particle comprising the porous core and the outer shell,
wherein a) through d) are determined with an inductively-coupled plasma emission spectrometer from an aqueous solution of 0.2 g of the particles completely dissolved in 60 mL of pure water, 20 mL of 1 N hydrochloric acid, and 20 mL of 1 N nitric acid.

US Pat. No. 10,996,576

MAGNETIC CORE MATERIAL FOR ELECTROPHOTOGRAPHIC DEVELOPER, CARRIER FOR ELECTROPHOTOGRAPHIC DEVELOPER, AND DEVELOPER

POWDERTECH CO., LTD., Ka...

1. A magnetic core material for electrophotographic developer, having a sulfur component content of from 50 to 700 ppm in terms of a sulfite ion and a BET specific surface area of from 0.06 to 0.25 m2/g, wherein the sulfur component content is from 80 to 500 ppm in terms of a sulfate ion.

US Pat. No. 10,969,706

MAGNETIC CORE MATERIAL FOR ELECTROPHOTOGRAPHIC DEVELOPER, CARRIER FOR ELECTROPHOTOGRAPHIC DEVELOPER, AND DEVELOPER

POWDERTECH CO., LTD., Ka...

1. A magnetic core material for electrophotographic developer, having a sulfur component content of from 60 to 800 ppm on a weight basis and a pore volume of from 30 to 100 mm3/g, wherein the sulfur content is quantified by detection of sulfate ions.

US Pat. No. 10,258,970

FERRITE PARTICLES PROVIDED WITH OUTER SHELL STRUCTURE FOR CATALYST SUPPORTING MEDIUM

POWDERTECH CO., LTD., Ch...

1. A ferrite particle comprising a ferrite core and an outer shell, the outer shell comprising Ti oxide, the outer shell having a thickness of 0.5 to 10 ?m.
US Pat. No. 11,029,618

CARRIER, ELECTROPHOTOGRAPHIC DEVELOPER AND PRODUCTION METHOD OF CARRIER

POWDERTECH CO., LTD., Ka...

1. A carrier comprising:(i) a magnetic core material having a surface; and
(ii) a resin coat layer coating the core material surface, wherein the resin coat layer comprises a mixture of:
(a) an elemental fluorine-containing resin;
(b) a polyimide (PI) resin having an imide bond in the main chain; and
(c) a surfactant;
wherein:
the surfactant has an elution amount of from 180 ppm to 3,500 ppm, remaining in water in an elution test comprising mixing the carrier into the water, filtering the carrier from the water, and measuring a weight of eluted material remaining after being removed from the water and dried, and
a mass ratio of the polyimide (PI) resin to the elemental fluorine-containing resin in the resin coat layer of 1/10 or more.

US Pat. No. 11,014,826

FERRITE PARTICLES, RESIN COMPOSITION AND RESIN FILM

POWDERTECH CO., LTD., Ch...

1. Ferrite particles, wherein the ferrite particles are composed of a single crystalline body having an average particle size of 1 to 2000 nm, are Mn-based ferrite particles having a spherical particle shape, and have a saturation magnetisation of 45 to 95 Am2/kg;wherein the metal component is composed of Mn and Fe, and contains Mn in a content of 1 to 23% by weight, and Fe in a content of 58 to 65% by weight.

US Pat. No. 10,996,579

MAGNETIC CORE MATERIAL FOR ELECTROPHOTOGRAPHIC DEVELOPER, CARRIER FOR ELECTROPHOTOGRAPHIC DEVELOPER, AND DEVELOPER

POWDERTECH CO., LTD., Ka...

1. A magnetic core material for electrophotographic developer, satisfying a value of Expression (1): a+b x 10+c+d+e+f, being from 200 to 1,400, when an amount of fluorine ion is denoted by a (ppm), an amount of chlorine ion is denoted by b (ppm), an amount of bromide ion is denoted by c (ppm), an amount of nitrite ion is denoted by d (ppm), an amount of nitrate ion is denoted by e (ppm), and an amount of sulfate ion is denoted by f (ppm), which are measured by combustion ion chromatography; and having a pore volume of from 30 to 100 mm3/g.

US Pat. No. 10,919,779

IRON OXIDE POWDER FOR BRAKE FRICTION MATERIAL

POWDERTECH CO., LTD., Ch...

1. An iron oxide powder for a brake friction material having:an average particle diameter of 40 ?m or more, and
a saturation magnetization of 20 emu/g or less.

US Pat. No. 10,825,593

NI—ZN—CU FERRITE PARTICLE, RESIN COMPOSITION, AND RESIN MOLDING

POWDERTECH CO., LTD., Ch...

1. A Ni-Zn-Cu ferrite particle in a single crystalline body having an average particle diameter of 1 to 2000 nm, having a polyhedral particle shape, comprising 5 to 10 wt % of Ni, 15 to 30 wt % of Zn, 1 to 5 wt % of Cu, and 25 to 50 wt % of Fe.

US Pat. No. 10,775,711

FERRITE CARRIER CORE MATERIAL FOR ELECTROPHOTOGRAPHIC DEVELOPER, FERRITE CARRIER FOR ELECTROPHOTOGRAPHIC DEVELOPER, ELECTROPHOTOGRAPHIC DEVELOPER, AND METHOD FOR MANUFACTURING FERRITE CARRIER CORE MATERIAL FOR ELECTROPHOTOGRAPHIC DEVELOPER

POWDERTECH CO., LTD., Ch...

1. A ferrite carrier core material for an electrophotographic developer, comprising a ferrite particle containing:15 mass % or more and 25 mass % or less of Mn,
0.5 mass % or more and 5.0 mass % or less of Mg,
0.05 mass % or more and 4.0 mass % or less of Sr,
45 mass % or more and 55 mass % or less of Fe, with Si localized in the surface thereof, and
a Cl concentration of 0.1 ppm or more to 50 ppm or less as measured in an elution testing of the ferrite carrier core material, the elution testing being performed by:
(a) consecutively adding to a 150 ml glass bottle: 50.000 g±0.0002 g of the ferrite carrier core material, 50 ml of a phthalate (pH: 4.01), and 1 ml of an ionic strength conditioner;
(b) closing the glass bottle and shaking the glass bottle on a paint shaker for 10 minutes to obtain a mixture;
(c) applying a magnet to the bottom of the glass bottle, and filtering the mixture into a 50 ml vessel made of PP through filter paper No. 5B to obtain a supernatant;
(d) measuring the voltage of the supernatant with a pH meter; and
(e) comparing the measured voltage to a calibration curve of voltages measured from pure water and solutions having Cl concentrations of 1 ppm, 10 ppm, 100 ppm, and 1000 ppm to calculate the Cl concentration of the ferrite carrier core material.

US Pat. No. 10,754,271

MAGNETIC CORE MATERIAL FOR ELECTROPHOTOGRAPHIC DEVELOPER, CARRIER FOR ELECTROPHOTOGRAPHIC DEVELOPER, AND DEVELOPER

POWDERTECH CO., LTD., Ka...

1. A magnetic core material for electrophotographic developer, satisfying a value of Expression (1): a +b [[]]?10+c +d +e +f, being from 300 to 1,300, when an amount of fluorine ion is denoted by a (ppm), an amount of chlorine ion is denoted by b (ppm), an amount of bromide ion is denoted by c (ppm), an amount of nitrite ion is denoted by d (ppm), an amount of nitrate ion is denoted by e (ppm), and an amount of sulfate ion is denoted by f (ppm), which are measured by combustion ion chromatography; and having a BET specific surface area being from 0.06 to 0.25 m2/g.
US Pat. No. 10,248,039

CARRIER, ELECTROPHOTOGRAPHIC DEVELOPER, AND METHOD OF MANUFACTURING CARRIER

POWDERTECH CO., LTD., Ch...

1. A carrier which is a core material composed of a magnetic component and a non-magnetic component coated with a resin, characterized in thatthe carrier has water content of 200 ppm or less and cyclic siloxane content of 100 ppb or less.