Ricoh Company, Ltd.

Mamoru Hozumi

Osamu Uchinokura

Tsuyoshi Sugimoto

Daisuke Inoue

Naohiro Watanabe

Shinya Hanatani

Junichi Awamura

Daisuke Ito

Satoshi Kojima

Satoshi Ogawa

Teruki Kusahara

Tomoyuki Satoh

Takahiro Honda

Tomoyuki Sato

Shoko Sato

Masaki Watanabe

Tsuneyasu Nagatomo

Tomoki Murayama

Ryuuta Yoshida

Syouko Satoh

Kiwako Hirohara

To provide a toner, containing: a binder resin; a colorant; a releasing agent; and a crystalline polyester resin, wherein the toner satisfies the following formulae (1) to (3): 40&#xb0; C.&#x2266;X&#x2266;55&#xb0; C. Formula (1) 85&#xb0; C.&#x2266;Y&#x2266;92&#xb0; C. Formula (2) 35&#xb0; C.&#x2266;Y&#x2212;X&#x2266;50&#xb0; C. Formula (3) where X is an onset temperature and Y is an endset temperature of an endothermic peak on a differential scanning calorimetry (DSC) curve of the toner as measured by a differential scanning calorimeter (DSC).

Toner and developer

A toner set, including: a transparent toner including a binder resin a, a releasing agent a and no colorant; and one or more color toners, each including a binder resin b, a colorant b and a releasing agent b, wherein the binder resin a includes a non-crystalline resin &#x3b1; and a crystalline resin &#x3b1;, the binder resin b includes a non-crystalline resin &#x3b2; and a crystalline resin &#x3b2;, the releasing agent a has an average particle diameter as a long diameter of 0.2 &#x3bc;m to 2.0 &#x3bc;m, and there is a relationship of 1&#x3c;A/B&#x3c;1.5, where A is an area of the releasing agent a in a transparent toner cross-section from a surface thereof to a &#x2153;-depth of a volume-average particle diameter, and B is an area of the releasing agent b in a color-toner cross-section from a surface thereof to a &#x2153;-depth of a volume-average particle diameter.

Toner set, developer set, and image forming apparatus

A toner including a binder resin which contains a crystalline polyester resin and a non-crystalline polyester resin, wherein the crystalline polyester resin has at least two diffraction peaks in a range of 20&#xb0;&#x3c;2&#x3b8;&#x3c;25&#xb0; as detected by X-ray diffraction measurement, and has a melting point which is 60&#xb0; C. or higher but lower than 80&#xb0; C., and wherein the diffraction peaks each have a half width which is less than 1.0&#xb0;.

Toner containing crystalline polyester

A toner including: a binder resin containing a non-crystalline resin and a crystalline resin; a colorant; and, a releasing agent, wherein the releasing agent has a melting point of 55&#xb0; C. to 80&#xb0; C., and wherein the toner satisfies the following Expressions 1 and 2: (Expression 1): 20,000 Pa&#xb7;s&#x2266;G&#x2266;50,000 Pa&#xb7;s; and (Expression 2): (G/G)/(G/G) 1.00, where Gis a storage modulus, Gis a loss modulus, Gis a storage modulus and Gis a loss modulus, and the storage modulus Gand the loss modulus Gare measured at 80&#xb0; C. when the toner is heated from 70&#xb0; C. to 150&#xb0; C. and the storage modulus Gand the loss modulus Gare measured at 80&#xb0; C. when the toner heated to 150&#xb0; C. is cooled to 70&#xb0; C.

Toner, developer and image forming apparatus

A toner including base particles each containing a crystalline polyester and a non-crystalline polyester, wherein the toner has a glass transition temperature of 45&#xb0; C. or higher where the glass transition temperature is determined from a DSC curve of the toner obtained in the first elevation of temperature thereof, and wherein the toner has a temperature width of 8&#xb0; C. or lower where the temperature width is a temperature width at &#x2153; the height of an endothermic peak attributed to the crystalline polyester in the DSC curve.

Toner and method for producing the same

To provide a toner, which contains: toner base particles each containing a binder resin and a colorant; and an external additive containing inorganic particles and fatty acid metal salt particles, wherein the inorganic particles contain at least hydrophobic silica particles, wherein a liberation ratio Ya of the hydrophobic silica particles from the toner is 1% by mass to 20% by mass, and wherein a libration ratio Yb of the fatty acid metal salt particles from the toner is 30% by mass to 90% by mass.

Toner and image forming apparatus

To provide a toner, containing: a binder resin; a crystalline polyester resin; a colorant; and wax, wherein the toner has a fluidized powder characteristic value of 35% to 45%, and a BET specific surface area of 2.8 m/g to 4 m/g, and wherein the toner has an intensity ratio P2850/P828 of 0.10 to 0.20, where P2850 is an intensity of a peak at 2850 cmwhich is attributed from the wax and the crystalline polyester resin, and P828 is an intensity of a peak at 828 cmwhich is attributed from the binder resin, as measured by total reflectance infrared spectroscopy.

Toner, production method thereof, developer and image forming method

A toner containing toner particles, each toner particle containing: a releasing agent; a colorant; and a binder resin containing at least a crystalline polyester resin and a non-crystalline polyester resin, wherein in the case where a volume average particle diameter of the toner is defined as Dv, the toner contains a group of the toner particles having 4/5 Dv, and a group of the toner particles having 6/5 Dv, and wherein an endothermic value A of the crystalline polyester resin at a first temperature increase in DSC of the toner, an endothermic value B of the crystalline polyester resin at a first temperature increase in DSC of the group of the toner particle having 4/5 Dv, and an endothermic value C of the crystalline polyester resin at a first temperature increase in DSC of the group of the toner particles having 6/5 Dv satisfy the relation represented by the following formulas:50&#x3c;()&#xd7;100&#x3c;90, and110&#x3c;()&#xd7;100&#x3c;150.

Toner, developer, image forming method and image forming apparatus

A toner containing a binder resin, a colorant, and a releasing agent, wherein the colorant contains a mixed crystal of a C. I. PIGMENT YELLOW 185 and a C. I. PIGMENT YELLOW 139, and wherein a mass ratio of the C. I. PIGMENT YELLOW 185 to the C. I. PIGMENT YELLOW 139 (mass of the C. I. PIGMENT YELLOW 185/mass of the C. I. PIGMENT YELLOW 139) in the toner is 95/5 to 50/50.

Toner, developer, and image forming method

A toner containing: a non-crystalline polyester resin; a crystalline polyester resin; a releasing agent; a graft-modified polymer; and a colorant, wherein the graft-modified polymer is a polymer having a glass transition temperature of higher than 40&#xb0; C. but lower than 80&#xb0; C., and obtained by grafting an acrylic resin onto at least one of a hydrocarbon wax and a crystalline polyester resin, and wherein a SP value of the non-crystalline polyester resin is defined as SP1, a SP value of the crystalline polyester resin is defined as SP2, a SP value of the releasing agent is defined as SP3, and a SP value of the graft-modified polymer is defined as SP4, and SP1, SP2, SP3 and SP4 satisfy relations represented by Formulas (1) to (3): 

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Miyagi, Japan

Mamoru Hozumi