Canon Kabushiki Kaisha

Masami Fujimoto

Yoshihiro Ogawa

Katsuhisa Yamazaki

Daisuke Yoshiba

Toru Takahashi

Hirohide Tanikawa

Koji Nishikawa

Hiroyuki Fujikawa

Yojiro Hotta

Toshiaki Nakahara

Kazuyoshi Hagiwara

Takakuni Kobori

Shotaro Nomura

Hiroki Akiyama

Kazuo Terauchi

Tsutomu Onuma

Masaaki Taya

Minoru Shimojo

Syuhei Moribe

Keisuke Tanaka

Shuhei Moribe

Daisuke Tsujimoto

Kiyoshi Mizoe

Takaaki Furui

Ryo Nagata

Motohide Shiozawa

Keita Nozawa

Takeshi Naka

Rika Shinba

Takashige Kasuya

Yushi Mikuriya

Masayoshi Shimamura

Kazuyuki Sato

Yu Yoshida

Shohei Tsuda

Shuichi Hiroko

Yusuke Kosaki

Takuya Mizuguchi

Kuniko Kobayashi

Kouji Nishikawa

Kenji Okado

Shingo Ito

Tsuneyoshi Tominaga

Akane Masumoto

Masaki Uchiyama

Takaaki Kohtaki

Kiichiro Sakashita

Yasukazu Ikami

Shigeto Tamura

Junko Nishiyama

Naohiko Tsuchida

Junko Hirata

Kousuke Yamamoto

Tooru Takahashi

Hirata Junko

Minoru Shimojyo

A toner including a toner particle; and an external additive, wherein the external additive contains strontium titanate particle, and when in a projected image of the strontium titanate particle photographed using a scanning electron microscope, a standard deviation of a distance from a center of the projected image to an outline of the projected image is Ds, and a circle-equivalent diameter of the projected image is Da, a value CV calculated by Equation (1) is 0.07 or less,/(/2)&#x2003;&#x2003;(1).

Toner

A toner contains toner particles, titanate fine particles having a Group II element, and hydrotalcite compound fine particles as an external additive and satisfying 10&#x2264;Lt&#x2264;80 and 100&#x2264;Lh&#x2264;Weight average particle diameter (D4) of toner particles&#xd7;0.50, when the number average particle diameter (D1) of primary particles of the titanate fine particles is defined as Lt (nm) and the number average particle diameter (D1) of primary particles of the hydrotalcite compound fine particles is defined as Lh (nm).

A toner including a toner particle and an external additive, wherein the external additive contains an inorganic fine particle A and a silica fine particle; in a surface of the toner observed using a scanning electron microscope, a number-average particle diameter of primary particle of the silica fine particle is from 5 nm to 50 nm, a number-average particle diameter of primary particle of the inorganic fine particle A is at least 10 nm and less than 60 nm, a coverage ratio X1 of the toner surface covered by the silica fine particle is from 60 area % to 95 area %, the inorganic fine particle A is a fine particle of a titanate having a Group 2 element, and a coverage ratio X2 of the toner surface covered by the inorganic fine particle A is from 5 area % to 40 area %.

Provided is toner that contains a toner particle, and an external additive containing a strontium titanate particle, wherein the toner has an average circularity of at least 0.935 and not more than 0.995, the strontium titanate particle has a number-average primary particle diameter of at least 10 nm and not more than 60 nm, the strontium titanate particle has a peak in the range of 39.700&#xb0;&#xb1;0.150&#xb0; and a peak in the range of 46.200&#xb0;&#xb1;0.150&#xb0; in a CuK&#x3b1; x-ray diffraction spectrum obtained in the 2&#x3b8; range of at least 10&#xb0; and not more than 90&#xb0; where &#x3b8; is the Bragg angle, and the ratio of the area Sb of the peak at 46.200&#xb0;&#xb1;0.150&#xb0; to the area Sa of the peak at 39.700&#xb0;&#xb1;0.150&#xb0; is at least 1.80 and not more than 2.30.

A toner comprising an external additive A, and a toner particle containing a binder resin and a colorant, wherein the external additive A: i) is an external additive that has a charge control agent on the surface thereof; ii) has a wall friction angle &#x3b8; calculated from the following formula (1) of not more than 25.0&#xb0;&#x3b8;=&#x3c4;/5.0&#x2003;&#x2003;formula (1);iii) has a number-average particle diameter (D1) of primary particles of at least 70 nm and not more than 500 nm; and iv) has a solidity as given by the following formula (2) of at least 0.40 and not more than 0.90solidity=area of external additive/area of region encompassed by envelope for external additive&#x2003;&#x2003; formula (2).

Toner and method of producing toner

A toner having excellent development performance, low-temperature fixation, and high-temperature storage stability is provided. An external additive contained in this toner is an organic-inorganic composite fine particle containing an inorganic fine particle embedded in a resin fine particle. The resin fine particle is made from a resin having a melting point of 60&#xb0; C. or more and 150&#xb0; C. or less.

A toner comprising: a toner particle containing a toner base particle containing a binder resin and a colorant, and a resin particle fixed to a surface of the toner base particle; and an inorganic fine particle A, wherein the surface of the toner particle has protruded portions originating in the resin particle, an average length (D) of long sides of the protruded portions is 50 nm to 300 nm, an average Height (H) of the protruded portions is 25 nm to 250 nm, the average long-side length and the average height of the protruded portions satisfies a specific relationship, and an average value of a compactness of the inorganic fine particle A is 0.40 to 0.80, and the attachment rate of the inorganic fine particles A is 0.1% to 5.0% by area.

Provided is a toner that uses a crystalline resin, and demonstrates favorable dispersibility of the crystalline resin in the toner, demonstrates superior low-temperature fixability, and is able to inhibit fogging. The toner has a toner particle comprising a resin A, which has a long-chain alkyl group having an average number of carbon atoms of 27 to 50, and a crystalline resin, wherein the SP value (cal/cm)of the crystalline resin is 9.00 to 12.00, and in a GC/MS analysis of components that volatize when the toner is heated for 10 minutes at 200&#xb0; C., the amount of volatile components of saturated hydrocarbons having 30 to 37 carbon atoms is 90 ppm to 260 ppm of toluene equivalent, based on mass.

A toner having compatibility between transfer properties and cleaning properties is provided. A toner wherein a fine particle A containing a primary particle having a number average particle diameter (D1) of 80 nm or more and 400 nm or less is present on the surface of a toner particle at a coverage ratio of 5 to 40%, a fixing rate of 30 to 90% by mass, and a variation coefficient of 0.1 to 0.5 in a region of 0.5 &#x3c0;&#x3bc;m.

Toner and imaging method

Provided is a toner having good endurance stability and good low-temperature fixability in high-speed printing, and having good resistance to the adhesion of printed paper. The toner is a magnetic toner having, on the surface of toner particle containing a binder resin and an ester compound as a releasing agent, inorganic fine particle 'a' and organic-inorganic composite fine particle having a volumetric specific heat of from 2,900 kJ/(m&#xb7;&#xb0; C.) to 4,200 kJ/(m&#xb7;&#xb0; C.), in which a coverage A of the surface of the toner particle with the inorganic fine particle 'a' is 45.0% or more and 70.0% or less.

Magnetic toner

Provided is a toner that has excellent low-temperature fixability and is capable of obtaining an image having a stable image density, in which the occurrence of image defects is suppressed. The toner includes toner base particles, each of which contains a binder resin and a magnetic material, and organic-inorganic composite fine particles on each of the toner base particles. Each of the organic-inorganic composite fine particles comprises a vinyl resin particle, and inorganic fine particles which are embedded in the vinyl resin particle, and at least a part of which are exposed. The volumetric specific heat of the organic-inorganic composite fine particles and the volumetric specific heat of the toner base particles satisfy a predetermined provision.

The toner includes a resin component containing a crystalline polyester resin and a polyester-type resin that has a long-chain monomer bonded by condensation at a terminal, the toner having, in a total heat flow measured by a temperature-modulated differential scanning calorimeter, an endothermic peak resulting from the crystalline polyester resin in a specific temperature range, and the percentage of the endothermic quantity of the endothermic peak in a reversing heat flow with respect to the endothermic quantity of the endothermic peak in the total heat flow being at least 20.0%.

The present invention provides a toner that exhibits an excellent low-temperature fixability and an excellent ejected paper adhesiveness during high-speed printing, without affecting the long-term storage stability, in which the toner has a toner particle that contains a resin component, wherein the toner has, in a DSC curve measured with a differential scanning calorimeter, a glass transition temperature of at least 50&#xb0; C. and not more than 65&#xb0; C. and a cold crystallization peak during cooling of at least 40&#xb0; C. and not more than 70&#xb0; C., and has an endothermic peak in a DSC curve measured with a differential scanning calorimeter for the resin component of at least 70&#xb0; C. and not more than 95&#xb0; C.

The toner comprises: toner particles each containing a binder resin and a releasing agent; and an organic-inorganic composite fine particle, wherein: the organic-inorganic composite fine particle comprises: a vinyl resin particle containing a vinyl resin, the vinyl resin containing THF-insoluble matter in an amount of 95% by mass or more; and inorganic fine particles which are exposed at surfaces of the respective organic-inorganic composite fine particles, the organic-inorganic composite fine particle 1) has a plurality of convexes derived from the inorganic fine particles on the surfaces thereof, 2) has a number average particle size of 70-500 nm, and 3) has a shape factor SF-2 as measured at a magnification of 200,000 times of 103-120, and an absolute value of difference between an SP value of the releasing agent and an SP value of the vinyl resin is 0.50 (cal/cm)or less.

A toner excellent in end-portion hot offset properties is provided. A toner including toner particles and an external additive, wherein the toner particles contain a binder resin, and organic-inorganic composite fine particles dispersed in the binder resin, and the organic-inorganic composite fine particles (1) have a number-average particle diameter of 70 nm or more and 500 nm or less, (2) have a structure in which inorganic fine particles are embedded in a resin particle, convexes derived from the inorganic fine particles being present on surfaces of the organic-inorganic composite fine particles, (3) have a shape factor SF-2 of 103 or more and 120 or less, and (4) contain a resin component in which a proportion of THF-insoluble matter based on a mass of the resin component is 95% by mass or more.

Growing community of inventors

Suntou-gun, Japan

Masami Fujimoto