41results about How to "Excellent offset resistance" patented technology

A toner for developing an electrostatic image, including a colorant, a binder resin comprising a modified polyester, and fine resin particles having a weight average particle diameter of 50 to 300 nm and being present on an outer surface of the toner, wherein the toner has a BET specific surface area of 1.5 to 4.0 m2 / g.

The present invention is directed to a toner for electrophotography that exhibits excellent hot offset resistance, storability, and glossiness and can obtain a high image-resolution and highly detailed images when used for energy saving apparatuses or as a color toner. The present invention is also directed to a developer, image-forming apparatus, and process cartridge containing such toner, and image-forming process using such toner. The toner of the present invention contains a resin and wax. The wax is dispersed within the resin in a shaped of fine particles to form a toner particle. In the toner particle, more dispersed wax particles are existed in a surface portion of the toner particle than a centric portion of the toner particle.

To provide a toner that contains at least a binder resin, a colorant, a releasing agent and zeolite, the toner being manufactured through O / W type wet granulation and having an average circularity of 0.970 or greater, and a developer and image forming method using the toner.

To provide an image forming method including forming a latent electrostatic image on a latent electrostatic image bearing member, developing the latent electrostatic image using a toner to form a visible image, transferring the visible image to a recording medium, and fixing a transfer image transferred on the recording medium, wherein the toner includes a toner base particle containing at least a binder resin, a colorant and an inorganic fine particle, and a charge control agent; and wherein the condition Xsurf>Xtotal is satisfied (where Xsurf is an average proportion of the inorganic fine particles in a near-surface region of the toner base particle, Xtotal is an average proportion of inorganic fine particles in the whole toner base particle.

To provide a toner including: a toner material that contains at least a binder resin, a pigment, and a pigment dispersant, wherein the pigment dispersant has an acid value of 20 mgKOH / g to 50 mgKOH / g and an amine value of 1 mgKOH / g to 50 mgKOH / g, and wherein the pigment contains at least aluminum phthalocyanine.

Provided is a toner that shows both developability and electrostatic offset resistance. The toner includes a charge controlling agent that is represented by the following formula (1), and that has peaks at 15.000°±0.150° and 20.100°±0.150° in CuKα X-ray diffraction spectrum obtained in 2θ range of 10° or more to 40° or less where θ represents Bragg angle, one of the peaks being a peak having a maximum intensity and the other being a peak having a second maximum intensity.

To provide a toner prepared by emulsifying or dispersing a solution or dispersion of a toner material in an aqueous medium containing fine resin particles for granulation, wherein at least one of the toner material and the aqueous medium contains a polyalkylene glycol ester compound that is compatible with the fine resin particles and that has a weight average molecular weight of 2,000 or greater.

A toner obtained by a method for producing a toner, which includes dissolving or dispersing in an organic solvent a toner material containing at least a binder resin, and a dispersion liquid of a crystalline polyester resin, so as to prepare a solution or dispersion liquid of the toner material, emulsifying or dispersing the solution or dispersion liquid of the toner material in an aqueous medium, so as to prepare an emulsion or dispersion liquid, and removing the organic solvent from the emulsion or dispersion liquid, wherein the crystalline polyester resin is localized near a surface of the toner.

Provided is a toner including at least: a binder resin; and a colorant, in which: the binder resin contains at least a polyester unit and a vinyl copolymer unit; a main peak MpA is present in the molecular weight region of 2,000 to 7,000 in a molecular weight distribution measured by means of gel permeation chromatography (GPC) of a specific tetrahydrofuran (THF) soluble matter A measured by a specific method; a main peak MpB is present in the molecular weight region of 5,000 to 10,000 in a molecular weight distribution measured by means of GPC of a specific THF soluble matter B which contains a component of a molecular weight region of 100,000 or less in range from 70 to 100 mass %, and the peak molecular weight MpA of the THF soluble matter A and the peak molecular weight MpB of the THF soluble matter B satisfy a specific equation.

The present invention relates to a binder resin for a toner which is used in electrophotography and the like. An objective of the present invention is to obtain a binder resin for a toner containing a crystalline resin which satisfies both excellent low temperature fixing property and excellent offset resistance, a method for producing the binder resin, and a toner using the binder resin. The objective can be achieved by using a binder resin for a toner that is produced by subjecting an amorphous resin and a crystalline resin to melting, kneading and reaction, and is characterized in that it includes a network structure which includes a crystalline resin.

A binder resin for a toner containing a vinyl resin (A), a non-crystalline polyester resin (SN) and a saturated crystalline polyester resin (SC), in which the content of the vinyl resin (A) is equal to or more than 65 mass % and equal to or less than 95 mass %, based on the total content of 100 mass % of (A), (SN) and (SC), (A) is composed of a carboxyl group-containing vinyl resin (C), a glycidyl group-containing vinyl resin (E) and a reaction product of the vinyl resins, the ester group concentration of (SC) is equal to or more than 10.0 mmol / g and equal to or less than 13.5 mmol / g, (SN) is dispersed in an island form in (A) and (SC) is contained in the island phase of (SN), and the metal component (M) containing at least one kind selected from the group consisting of Zn, Ca, Mg, Al and Ba (excluding metal oxide) is contained at least in (SC).

A toner for electrophotography is disclosed. The toner comprises a binder resin and a colorant and a wax in amount of 0.5 to 8 percent by weight, and adhesion power index of wax particles to toner particles is between 0.7 and 2.2. The toner improves the durability of the developer material and a photoreceptor, minimizes image smear at high temperature and humidity, and exhibits excellent fixation as well as offsetting resistance.

The invention relates to a preparing method for a styrene-acrylic resin / polyester resin compound type static charge image color matching agent and provides the preparing method for the color matching agent good in low-temperature image setting property and good in image quality. According to the technical scheme, the styrene-acrylic resin / polyester resin compound type static charge image color matching agent is obtained by agglutinating styrene-acrylic copolymer composite emulsion (A) containing a coloring agent and polyester compound emulsion (B) containing wax. The styrene-acrylic copolymer composite emulsion (A) containing the coloring agent is prepared from the coloring agent, styrene class monomers and acrylic class monomers under the action of a cationic surface active agent through an emulsion polymerization method. The polyester compound emulsion (B) containing the wax is prepared from the wax, unsaturated monomers containing polyester structure units and acrylic class monomers under the action of an anionic surface active agent through the emulsion polymerization method. The preparing method for the styrene-acrylic resin / polyester resin compound type static charge image color matching agent is simple in technology, low in cost and good in compatibility, the color matching agent has the good offset-resisting property and storage stability, and high image quality can be still kept under extreme conditions.

An electrophotographic toner contains a resin, a colorant and a releasing agent. The releasing agent has a solidifying point of from 79° C. to 109° C., and one peak in an endothermic curve measured by a differential scanning calorimeter. A difference between temperature to give a maximum endothermic peak of the releasing agent and an end-set temperature of the releasing agent is within 10° C. A melt viscosity of the releasing agent at 110° C. is in a range of from 4 mPa.s to 9 mPa.s. The releasing agent in one particle of the toner forms 3 or more domains. Domains having a ratio of a major axis to a minor axis which is in a range of from 5 to 15 occupy 90% or more by number based on the total number of domains.

A toner obtained by a method for producing a toner, which includes dissolving or dispersing in an organic solvent a toner material containing at least a binder resin, and a dispersion liquid of a crystalline polyester resin, so as to prepare a solution or dispersion liquid of the toner material, emulsifying or dispersing the solution or dispersion liquid of the toner material in an aqueous medium, so as to prepare an emulsion or dispersion liquid, and removing the organic solvent from the emulsion or dispersion liquid, wherein the crystalline polyester resin is localized near a surface of the toner.

To provide a toner that contains at least a binder resin, a colorant, a releasing agent and zeolite, the toner being manufactured through O / W type wet granulation and having an average circularity of 0.970 or greater, and a developer and image forming method using the toner.

The present invention was investigated for the purpose of providing a binder resin for toner which is excellent in the low temperature fixing property which can cope with the development of high-speed copier machines, and is excellent in the offset resistance, blocking resistance, pulverizability and development durability.As a result, it was found that the purpose could be achieved by using, as a binder resin for toner, a resin that can be obtained from at least three different vinyl polymers with different molecular weight, contents of functional groups, and preferably from a crosslinking agent having the vinyl polymer structure, and that contains a specific gel component. This resin has excellent melting property at low temperatures, and has suitable performance as a material for toner and a toner in high-speed copier machines.

A toner comprising toner particles, each of which contains a binder resin and a colorant, wherein an onset temperature Te (° C.) of a storage elastic modulus E′ obtained in a powder dynamic viscoelastic measurement on the toner is at least 50° C. and not more than 70° C., and a value at Te (° C.) of a storage elastic modulus G′ obtained in a pellet dynamic viscoelastic measurement on the toner is at least 4.0×107 Pa and not more than 1.0×1010 Pa.

The present invention was investigated for the purpose of providing a binder resin for toner which is excellent in the low temperature fixing property which can cope with the development of high-speed copier machines, and is excellent in the offset resistance, blocking resistance, pulverizability and development durability. As a result, it was found that the purpose could be achieved by using, as a binder resin for toner, a resin that can be obtained from at least three different vinyl polymers with different molecular weight, contents of functional groups, and preferably from a crosslinking agent having the vinyl polymer structure, and that contains a specific gel component. This resin has excellent melting property at low temperatures, and has suitable performance as a material for toner and a toner in high-speed copier machines.

There are provided a capsule toner, a two-component developer, and a capsule toner manufacturing method. The capsule toner in which a resin coating layer made of fine release-agent particles and fine resin particles is made on the surfaces of toner base particles, and thus excellent offset resistance without impairing blocking resistance can be obtained. The capsule toner includes toner base particles containing a binder resin and a colorant, and a resin coating layer made of fine release-agent particles and fine resin particles, for covering the surfaces of the toner base particles. The fine release-agent particles are dispersed in the resin coating layer.

An electrophotographic toner contains a resin, a colorant and a releasing agent. The releasing agent has a solidifying point of from 79° C. to 109° C., and one peak in an endothermic curve measured by a differential scanning calorimeter. A difference between temperature to give a maximum endothermic peak of the releasing agent and an end-set temperature of the releasing agent is within 10° C. A melt viscosity of the releasing agent at 110° C. is in a range of from 4 mPa·s to 9 mPa·s. The releasing agent in one particle of the toner forms 3 or more domains. Domains having a ratio of a major axis to a minor axis which is in a range of from 5 to 15 occupy 90% or more by number based on the total number of domains.

Provided are a propylene-based polymer useful for providing a toner that is excellent in offset resistance, can be fixed by using a low-temperature heating element and hardly has stickiness even after stored for a long period of time; and a toner including said propylene-based polymer. The present invention is directed to a propylene / α-olefin copolymer (A) which includes 60 to 90 mol % of structural units derived from propylene (a) and 10 to 40 mol % of structural units derived from α-olefins having 4 or more carbon atom (b) wherein (a)+(b)=100 mol % and which satisfies: (i) a weight average molecular weight (Mw) as measured by GPC of 3,000 to 40,000; (ii) a melting point (Tm) as measured by DSC of 60 to 90° C.; and (iii) a half width of a crystalline melting point peak as measured by DSC of 1 to 20° C.

In the control method of the power converter circuit, a primary side independent control mode and a secondary side independent control mode are adopted to solve the problems of control stability and reliability caused by long time delay and the like of wireless communication in real-time information interaction, and avoid the problems of low electric energy conversion efficiency and low power density caused by a multi-stage circuit. For a primary side transmitting circuit, a phase shift angle alpha and a primary side dynamic compensation phase angle delta of an inverter are controlled, so thatpower transmission is adjusted, and the change of a coupling coefficient is adapted. For a secondary side receiving circuit, the phase shift angle beta of the rectifier and the phase difference phi between the input voltage and the input current of the rectifier are controlled, so that the equivalent load resistance is matched with the optimal load resistance, and the secondary side dynamic compensation phase angle rho is controlled, so that the reactance of the resonance network counteracts the equivalent load reactance, and the reactance of the secondary side impedance is zero. Through a primary side dynamic compensation phase angle delta and a secondary side dynamic compensation phase angle rho of the resonance network, primary side resonance capacitance and secondary side resonance capacitance are respectively adjusted, and disturbance of relative distance and offset between coils is counteracted.

To provide a toner prepared by emulsifying or dispersing a solution or dispersion of a toner material in an aqueous medium containing fine resin particles for granulation, wherein at least one of the toner material and the aqueous medium contains a polyalkylene glycol ester compound that is compatible with the fine resin particles and that has a weight average molecular weight of 2,000 or greater.

The present invention relates to a binder resin for a toner which is used in electrophotography and the like. An objective of the present invention is to obtain a binder resin for a toner containing a crystalline resin which satisfies both excellent low temperature fixing property and excellent offset resistance, a method for producing the binder resin, and a toner using the binder resin. The objective can be achieved by using a binder resin for a toner that is produced by subjecting an amorphous resin and a crystalline resin to melting, kneading and reaction, and is characterized in that it includes a network structure which includes a crystalline resin.

An image forming apparatus including: image bearing member; latent image forming unit; developing unit; transfer unit; fixing unit, wherein toner in the developing unit contains amorphous polymer, crystalline resin and releasing agent, when the toner is measured for G′ at 40° C. to 210° C. with rheometer at 1 Hz and 1 deg, G′(100) is ≦20,000 and G′(150) is ≧500 Pa, and straight line drawn by connecting points of the G′(100) and G′(110) on curve of the G′ has gradient of ≦0.035, the gradient being “a” expressed by: a=|log10G′(100)−log10G′(110)| / 10, and the fixing unit includes: heating member containing flexible endless belt; heat source fixed within the flexible endless belt; and press member in contact with the belt to form nip portion, and the fixing unit is configured to heat / press the medium passing through the nip portion to fix the image on the medium.

The object of this invention is to obtain an electrophotographic toner for electrostatic developing which has excellent grindability, fixing properties, anti-offset properties, storage properties and environmental stability. The binder resin for toner of this invention is characterized by a structure in which a polyester resin and a styrene resin are connected together through an epoxy radical derived structural unit. Qwing to the usage of the binder resin for toner described above, the toner of this invention has a balance of good fixing properties and anti-offset properties and has excellent environmental stability. Another binder resin for toner of this invention is characterized by having a wax derived structure along with the above structure, and it has improved grindability and storage properties along with the above properties.

In the control method of the power converter circuit, a primary side independent control mode and a secondary side independent control mode are adopted to solve the problems of control stability and reliability caused by long time delay and the like of wireless communication in real-time information interaction, and avoid the problems of low electric energy conversion efficiency and low power density caused by a multi-stage circuit. For a primary side transmitting circuit, a phase shift angle alpha and a primary side dynamic compensation phase angle delta of an inverter are controlled, so thatpower transmission is adjusted, and the change of a coupling coefficient is adapted. For a secondary side receiving circuit, the phase shift angle beta of the rectifier and the phase difference phi between the input voltage and the input current of the rectifier are controlled, so that the equivalent load resistance is matched with the optimal load resistance, and the secondary side dynamic compensation phase angle rho is controlled, so that the reactance of the resonance network counteracts the equivalent load reactance, and the reactance of the secondary side impedance is zero. Through a primary side dynamic compensation phase angle delta and a secondary side dynamic compensation phase angle rho of the resonance network, primary side resonance capacitance and secondary side resonance capacitance are respectively adjusted, and disturbance of relative distance and offset between coils is counteracted.