Samsung Electronics Co., Ltd.

S-printing Solution Co., Ltd.

Se-young Yoon

Hae-ree Joo

Sung-jin Park

Hong-chul Shin

Seung-sik Woo

Seung-Jun Lee

Jong-in Kim

Tae-hoe Koo

In-su Lee

Song-won Hyun

Sung-jun Cho

Sung-dong Lee

Disclosed is a toner for developing an electrostatic latent image, the toner comprising a plurality of toner particles, each toner particle includes: a core particle that contains a binding resin, a coloring agent, and a releasing agent; and an external additive attached to the surface of the core particle, wherein the toner has two endothermic peaks in a heat curve, which is obtained at the time of the secondary temperature rise in differential scanning calorimetry of the toner, and a stepped endothermic curve; and first and second melting temperatures, which are determined to be the locations of vertices of the two endothermic peaks, a glass transition temperature, which is determined to be the midpoint of a linear portion of the stepped endothermic curve, and first and second heat of melting, which are determined to be the areas of the two endothermic peaks, satisfy the condition set forth herein.

Toner for developing electrostatic latent image

A toner to develop electrostatic latent images which uses an appropriate combination of a high molecular weight binder resin and a low molecular weight binder resin, an appropriate amount of a releasing agent, and a combination of silica particles and iron oxide particles as external additives, and thus has the following effects: the toner may reduce a generation amount of ultra-fine particles (UFPs) and have enhanced fluidity, charging uniformity, charging stability, transfer efficiency, fixability, durability and a cleaning ability.

Toner to develop electrostatic latent images

A toner Tdevelops an electrostatic latent image, the toner Thaving relieved charge-up characteristics, improved development characteristics, and improved transfer characteristics. The toner Tmay ensure high charge stability against environmental condition changes, and an appropriate amount of charges at a high printing speed, may reduce background contamination on a photoreceptor, may prevent undesirable fusing onto a blade even after prolonged printing, and may have high transfer efficiency and high image uniformity. The toner Tmay have effective flowability and transportability, and may have good storage stability, so as to be unlikely to cause blocking when stored for an extended time.

Main performances of a toner are significantly affected by a shape and surface characteristics of toner particles. Using an external additive may be a factor that complicates control of surface characteristics of the toner particles, and anti-offset properties of toner change according to a wax and a binder composition at a surface portion of the toner particles. Provided is a toner usable in electrophotography, wherein the toner has improved durability, fixability, charging stability, and cleaning properties through an appropriate distribution of a binder, a wax, and an external additive on a surface portion of toner particles.

Electrophotography toner

A toner to develop electrostatic latent images, which has surface characteristics that may simultaneously improve charge uniformity, charge stability, transferability, and cleaning ability. The toner to develop electrostatic latent images may include core particles comprising a binder resin, a colorant, and a releasing agent; and an external additive including silica particles and titanium dioxide particles, wherein the external additive is attached to external surfaces of the core particles, wherein an iron intensity [Fe], a silicon intensity [Si], and a titanium intensity [Ti] that are measured by X-ray fluorescence (XRF) satisfy both conditions, 0.004&#x2266;[Si]/[Fe]&#x2266;0.009 and 0.8&#x2266;[Ti]/[Fe]&#x2266;2.

Disclosed is a toner for developing an electrostatic charge image, including a toner particle coated with a combination of sol-gel silica particles, hydrophobically surface-treated fumed silica particles, and hydrophobically surface-treated titanium dioxide particles.

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Hwaseong-si, South Korea

Se-young Yoon