JP2006330706A - Toner for electrostatic charge image development, method for manufacturing toner for electrostatic charge image development, image forming method, and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a toner for electrostatic charge image development for low temperature fixing specification so that even when a toner image on a transfer material is thermally fixed by a heating roll, the thermally fixed transfer material is prevented from winding on the heating roll. <P>SOLUTION: The toner for electrostatic charge image development containing at least a binder resin and a colorant is characterized in that the interface adhesion strength (Fr) between the toner for electrostatic charge image development and polytetrafluoroethylene is 1.0 to 3.5 N and that the inner cohesive force (Ft) of the toner is 10 to 18 N. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an electrostatic image developing toner, an electrostatic image developing toner production method, an image forming method, and an image forming apparatus.

  As energy saving progresses, in the electrophotographic industry, a technique for fixing a toner image on a transfer material at a low temperature has been developed.

  In order to achieve low-temperature fixing, low melting point of the wax used as a toner material and low softening design of the resin can be considered. However, the storage stability of the toner is deteriorated, and the fixing roll (hereinafter also referred to as a heating roll) is used. There is a new problem that the fixed transfer material is wound.

  As a measure against storage stability of the toner, a technique is adopted in which the toner has a core-shell structure having a core portion having a low glass transition temperature and a shell layer having a high glass transition temperature (see Patent Document 1).

However, even with this core / shell structure toner, the problem that the transfer material obtained by thermally fixing the toner image around the heating roll has not been solved yet.
JP 2004-191618 A

    The present invention relates to a toner for developing an electrostatic image having a low-temperature fixing specification (hereinafter, also simply referred to as toner) in which a toner image on a transfer material is heat-fixed by a heating roll, and the heat-fixed transfer material is not wound around the heating roll. The purpose is to provide.

  The object of the present invention is achieved by adopting the following configuration.

1.
In the electrostatic image developing toner containing at least a binder resin and a colorant, the interfacial adhesive force (Fr) between the electrostatic image developing toner and polytetrafluoroethylene is 1.0 to 3.5 N. An electrostatic charge image developing toner, wherein the electrostatic charge image developing toner has an internal cohesive force (Ft) of 10 to 18 N.

2.
2. The electrostatic image developing toner according to 1 above, wherein the electrostatic charge image developing toner has a softening point of 90 to 115 ° C.

3.
An electrostatic charge image developing toner manufacturing method having an aggregation step, wherein the resin particles B are added during the aggregation step of the resin particles A, and the aggregation is further advanced to complete the aggregation. Toner manufacturing method.

4).
3. An image forming method comprising a step of forming a toner image using the electrostatic charge image developing toner according to 1 or 2 above.

5.
5. An image forming apparatus using the image forming method described in 4 above.

  As the toner of the present invention, a toner having an adhesion force (Fr) between the toner and polytetrafluoroethylene of 1.0 to 3.5 N and an internal cohesion force (Ft) of 10 to 18 N is used. As a result, even if the toner image on the transfer material is heat-fixed by the heating roll, the transfer material heat-fixed on the heating roll has an excellent effect that the transfer material is not wound.

  The phenomenon that the heat-fixed transfer material is wound around the heat roll of the heat fixing device is that the separation property between the melt (heat-fixing) toner on the transfer material and the heat roll deteriorates, and the melted toner on the transfer material is transferred to the heat roll. It is presumed that the transfer material will adhere to the heating roll.

  Although the cause has not been elucidated, it is believed that there is some relationship in the adhesion between the heating roll and the melted (heat-fixing) toner, and the surface member of the heating roll, polytetrafluoroethylene (hereinafter abbreviated as PTFE), and the toner We examined the adhesive force between them.

  As a result of investigation, factors that adjust the interfacial adhesion include the type of wax, the amount of wax added, the composition and molecular design of the binder resin that constitutes the toner particles, and the structure design of the toner particles. It was found that the composition and molecular design of the binder resin constituting the toner and the structure design inside the toner particles are important factors.

  Here, the structure design inside the toner particles means how to design the presence state of the resin having different resin characteristics. For example, by making resin particles having a glass transition temperature higher than that of the entire toner particles in the vicinity of the surface of the toner particles to have a core / shell structure, the adhesion force at the interface can be reduced, and a resin having a high glass transition temperature can be obtained. It can be present in a dispersed state inside the toner particles to increase the elasticity of the binder resin, that is, to increase the internal cohesive force.

  As an achievement means for increasing the internal cohesion force of the toner, in the toner production method of the emulsion aggregation method, the stage where the aggregation of the resin particles A has progressed to some extent (the stage where the aggregation of the resin particles A is not completed = the first stage of aggregation) ), The resin particles B having a glass transition temperature (Tg) higher than that of the resin particles A are added, and the aggregation is further promoted to complete the aggregation (the second stage of aggregation). Can exist in a dispersed state.

  By the addition of the resin particles B, high Tg portions are locally formed in the toner particles and in the vicinity of the surface, and there are portions where fusion between the resin particles is difficult to proceed on a micro scale, and as a result, from the inside of the toner to the surface. It is presumed that a passage through which the wax exudes can be secured, the wax effectively acts on the surface of the toner image, and the adhesion force with PTFE can be reduced.

  First, the interfacial adhesion force, internal cohesive force, and toner softening point will be described.

  The adhesion force (Fr) between the toner and PTFE refers to the force required to peel off the toner after the surface-coated member is adhered to the toner exposed to an arbitrary temperature. .

  The interfacial adhesion force (Fr) between the toner and PTFE is 1.0 to 3.5 N, preferably 1.5 to 3.0 N.

  The internal cohesive force (Ft) of toner refers to the force required to tear off the toner after pressing the aluminum head against the toner exposed to an arbitrary temperature.

  The internal cohesive force (Ft) of the toner is 10 to 18N, preferably 11 to 16N.

  A toner having an interface adhesion force (Fr) and an internal cohesion force (Ft) in the above ranges can suppress wrapping around a heating roll in a fixing process even for a low softening point toner intended for low-temperature fixing. It becomes. Conventional toners usually have an interfacial adhesive force (Fr) of 3.5 N or more, and may be 3.5 N or less in toners that are prevented from being wrapped around a heating roll, but may have internal aggregation. The force (Ft) was also reduced to 10 N or less at the same time, and even with a low softening point toner, image defects and wrapping around the heating roll could not be prevented.

  FIG. 1 is a schematic view showing an example of a measuring apparatus for measuring the interfacial adhesion force (Fr) and the internal cohesive force (Ft).

  In FIG. 1, 11 is a lifting shaft, 12 is a load cell, 13 is a heat insulating member, 14 is a heating member (panel heater), 15 is a head portion, 17 is a holding member, 18 is a toner pellet, 19 is a contact surface, 20 Is a mounting member, 21 is a spring, 22 is a base, 23 is a data input device, and 24 is a data analysis device.

《Interface adhesion》
The interface adhesion force between the toner and PTFE was measured by attaching the head portion shown in FIG. 2 to the head portion 15 of the apparatus shown in FIG.

  FIG. 2 is a schematic diagram of a head for measuring the interfacial adhesion force (Fr).

  In FIG. 2, 31 is a Fr measuring head, 32 is a cylindrical head, 33 is a thermocouple, 34 is a heat-resistant double-sided tape, and 35 is a member coated with PTFE.

  The measuring device has, for example, a configuration of a toner pellet fixing member, a tension and pressing member (head), and a control device that controls pressure and temperature as shown in FIG. Similar to tensile strength tester or elongational viscosity measuring device.

  The toner used for the measurement is a press-molded pellet. Since the toner pellet is deformed at the time of pressing, parallelism between the upper surface and the lower surface is not guaranteed. Therefore, the toner pellet is pushed up from below so that the upper surface of the toner pellet contacts the reference surface of the apparatus.

  Moreover, since the pressure sensor (load cell) is sensitive to heat, a three-step heat insulation means was applied.

  A panel heater is used to heat the head, and the temperature is controlled by a thermocouple installed inside the head.

  In preparation for measurement, a member having a surface coated with PTFE and a heat-resistant double-sided tape was first attached to a cylindrical head (diameter 8 mm, material aluminum A5052) of the head portion.

  The member coated with PTFE is a member obtained by coating PTFE with a layer thickness of 20 to 30 μm on silicon rubber with a thickness of 0.5 mm.

  Next, the head is screwed and fixed with a heating member (panel heater) sandwiched between screw portions provided in the heat insulating material. A thermocouple is inserted into the hole provided in the head part, and the temperature controller “E5CN-RTC” (manufactured by OMRON) is turned on to set the measurement temperature. Prior to the measurement, the PTFE surface is wiped off with tetrahydrofuran, and toner pellets are attached.

  To produce the toner pellets, 2 g of toner left for 24 hours at a temperature of 24 ± 1 ° C. and a humidity of 50 ± 5% RH was placed in a circular vinyl chloride ring having an inner diameter of 34.5 mm, and the pressure was 150 kg with a powder compression apparatus. Compressed for 2 seconds.

  When the set temperature is reached, measurement is started under the following conditions, the value at which the load cell voltage is maximized is read, and the pressure converted value is taken as the interface adhesion.

Head lowering speed: 1mm / sec
Head pressing: 0.1N
Head pressing time: 1 sec
Head lifting speed: 50 mm / sec
Measurement environment: 24 ± 1 ℃, 50 ± 5% RH
The interface adhesion at 160 to 180 ° C. was measured at three points of measurement temperatures of 160 ° C., 170 ° C., and 180 ° C., and the average value was defined as Fr (160 to 180 ° C.).

<Inner cohesion>
The internal cohesive force was measured by attaching the head part shown in FIG. 3 to the head part 15 of the measuring apparatus shown in FIG.

  FIG. 3 is a schematic diagram of a head for measuring the internal cohesive force (Ft).

  In FIG. 3, reference numeral 41 denotes an Ft measurement head, 42 denotes a cylinder-type head, and 43 denotes a head having nine points.

  First, as a measurement head, a cylinder-type head having nine 1 mm × 1 mm points (material aluminum A5052) is prepared.

  Next, the head is screwed and fixed with a heating member (panel heater) sandwiched between screw portions provided in the heat insulating material. A thermocouple is inserted into the hole provided in the head, and the temperature controller “E5CN-RTC” (manufactured by OMRON) is turned on to set the measurement temperature. Before measurement, wipe the 9-point head surface with tetrahydrofuran and attach toner pellets.

  To produce the toner pellets, 2 g of toner left for 24 hours at a temperature of 24 ± 1 ° C. and a humidity of 50 ± 5% RH is placed in a circular vinyl chloride ring with an inner diameter of 34.5 mm, and the pressure is 150 kg with a powder compression device. Compressed for 10 seconds.

  When the set temperature is reached, measurement is started under the following conditions, the value at which the load cell voltage is maximized is read, and the pressure converted value is taken as the internal cohesive force.

Head lowering speed: 1mm / sec
Head pressing: 0.1N
Head pressing time: 1 sec
Head lifting speed: 50 mm / sec
Measurement environment: 24 ± 1 ℃, 50 ± 5% RH
The internal cohesive force at 100 to 120 ° C. was measured at three points of measurement temperatures of 100 ° C., 110 ° C., and 120 ° C., and the maximum value was defined as Ft (100 to 120 ° C.).

<Softening point of toner>
The softening point (Tsp) of the toner is preferably 90 to 115 ° C, more preferably 100 to 108 ° C.

  The softening point of the toner was measured as follows.

  As a measuring device for the softening point, “CFT-500D” (manufactured by Shimadzu Corporation) is used.

  First, in an environment of 20 ± 1 ° C. and 50 ± 5% RH, 1.1 g of toner is put in a petri dish and left flat for 12 hours or more. Then, using a molding machine “SSP-10A” (manufactured by Shimadzu Corporation). Pressure is applied with a force of 3 × 9.8 kN for 30 seconds to produce a cylindrical molded sample having a diameter of 1 cm.

  In the environment of 24 ± 1 ° C. and 50 ± 5% RH, the above molding apparatus was used to cast the molded sample under the conditions of a weight of 196 N, a starting temperature of 60 ° C., a preheating time of 300 seconds, and a heating rate of 6 ° C./min. The offset method temperature Toffset, which was extruded from the end of preheating using a 1 cm diameter piston from the hole (1 mm diameter × 1 mm) of the mold die and was measured at the setting of an offset value of 5 mm by the melting temperature measurement method of the temperature rising method, The softening point.

<Toner particle size>
The toner of the present invention has a median particle diameter (D ₅₀ ) on a volume basis of preferably 3 to 8 μm, and more preferably 4 to 7 μm.

The measurement of the median particle size (D ₅₀ ) on a volume basis is performed as follows.

  Measurement and calculation are performed using a device in which a computer system for data processing (manufactured by Beckman Coulter) is connected to "Coulter Multisizer III" (manufactured by Beckman Coulter). As a measuring means, 0.02 g of toner was conditioned with 20 g of a surfactant solution (for example, a surfactant solution in which a neutral detergent containing a surfactant was diluted 10 times with pure water for the purpose of dispersing the toner). Thereafter, ultrasonic dispersion is performed for 1 minute to prepare a toner dispersion. This toner dispersion is injected into a beaker containing ISOTON II (manufactured by Beckman Coulter, Inc.) in a sample stand with a pipette until a measurement concentration of 5 to 10% by mass, and the measuring machine count is set to 2500. To do. An aperture diameter of 50 μm is used.

<Production of toner>
Next, a method for producing the toner of the present invention will be described.

  As a method for producing the toner, at least a binder resin and a colorant are contained, the interfacial adhesion between the toner and PTFE is 1.0 to 3.5 N, and the internal cohesive force (Ft) of the toner is 10 to 18 N. The toner is not particularly limited as long as the toner is obtained, and examples thereof include a suspension polymerization method, an emulsion association method, a dispersion polymerization method, a dissolution suspension method, a melting method, and a kneading and pulverizing method.

  From the viewpoint of easy adjustment of the interfacial adhesion force and internal cohesion force, the emulsification association method is particularly preferable.

  Hereinafter, a method for producing the toner of the present invention by the emulsion association method will be described.

<Emulsion association method>
The emulsion association method is a method in which resin particles are prepared by agglomeration and fusion in an aqueous medium. The method is not particularly limited, and examples thereof include methods disclosed in JP-A-5-265252, JP-A-6-329947, and JP-A-9-15904. That is, the toner of the present invention can be formed by a method of salting out, aggregating, or fusing a plurality of particles composed of resin particles and colorants, or a plurality of particles composed of resin and colorant. it can.

  In the toner manufacturing method of the present invention, a release agent is dissolved or dispersed in a polymerizable monomer, and then finely dispersed in an aqueous medium, and the polymerizable monomer is polymerized by a miniemulsion polymerization method. A method of aggregating and fusing the composite resin particles formed through the process and the colorant particles is preferably used.

  As a method for adjusting the interfacial adhesion force and internal cohesion force, specifically, in the process in which the resin particles A are aggregated in a solution medium and the particles are growing (the stage where the aggregation of the resin particles A is not completed), the resin A toner manufacturing method is preferred in which the particles B are added and further agglomerated to continue particle growth, the resin particles B are taken into the previously agglomerated particles, and aggregation is completed when the desired particle size is reached.

  Further, by adding a hydrophilic resin and a hydrophobic resin to the resin particles A and coagulating and fusing them, the hydrophobic resin is present inside the toner particles, and the hydrophilic resin is present in the vicinity of the toner particle surface, so that A method of forming a shell structure is also preferable.

  An example of a preferable toner production method (emulsion polymerization association method) will be described in detail.

This manufacturing method includes
(1) Dissolution / dispersion step for dissolving or dispersing the release agent in the radical polymerizable monomer (2) Polymerization step for preparing a dispersion of resin particles A (3) Coloring with resin particles A in an aqueous medium First aggregating step (4) for fusing the agent particles. Further, a second aggregating step (5) for adding the resin particles B to complete the agglomeration. (6) Cooling step of cooling the dispersion of the toner base (7) Solid-liquid separation of the toner base from the cooled dispersion of the toner base, and removing the surfactant and the like from the toner base Washing step (8) Drying step of drying the washed toner base If necessary, (9) A step of adding an external additive to the dried toner base may be included.

  Hereinafter, each step will be described.

[Dissolution / dispersion process]
This step is a step of preparing a radical polymerizable monomer solution of the release agent by dissolving or dispersing the release agent in the radical polymerizable monomer.

[Polymerization process]
In a preferred example of this polymerization step, a radical polymerizable monomer solution in which the release agent is dissolved or dispersed is added to an aqueous medium containing a surfactant, and mechanical energy is applied to form droplets. Then, the polymerization reaction is allowed to proceed in the droplets by radicals from the water-soluble radical polymerization initiator. In addition, you may add the resin particle as a core particle in the said aqueous medium.

  By this polymerization step, resin particles containing a release agent and a binder resin are obtained. Such resin particles may be colored particles or non-colored particles. The colored resin particles can be obtained by polymerizing a monomer composition containing a colorant. Further, when using uncolored resin particles, a dispersion of colorant particles is added to the dispersion of resin particles in the fusing step described later, and the resin particles and the colorant particles are fused. Thus, a toner base can be obtained.

[Aggregation / fusion process]
As a method of fusing in the fusing step, an aggregation / fusing method using resin particles (colored or non-colored resin particles) obtained in the polymerization step is preferable. In the fusing step, resin particles and colorant particles can be fused together with release agent particles, internal additive particles such as charge control agents, and the like.

In particular,
(Aggregation first stage)
Aggregation of the resin particles A is started and particle growth is advanced to a target particle size.

For example, when a toner having a median particle size (D ₅₀ ) of 6 μm on a volume basis is produced, aggregation is advanced until the particle size of the aggregated particles grows to 30 to 70% of the toner particle size in the first aggregation stage.

(Addition of resin particles B)
When the toner particle size has grown to 30 to 70%, a dispersion of resin particles B is added.

  In addition, it is preferable to add 10-80 mass% of resin particles B with respect to the resin particles A.

(Aggregation second stage)
After the dispersion of resin particles B is added, aggregation is further advanced and the particles are grown to the final particle size. In the second stage of aggregation, the resin particles B are taken into the aggregate of the resin particles A.

(Aging (fusion) stage)
The particles in which the resin particles B are taken into the aggregates of the resin particles A are aged by heat energy, and a toner base in which the resin particles B are mixed in the aggregate particles is obtained.

  Incidentally, the toner base is the one before an external additive is added to obtain a toner.

[Cooling process]
This step is a step of cooling the toner base dispersion. As a cooling treatment condition, cooling is performed at a cooling rate of 1 to 20 ° C./min. The cooling treatment method is not particularly limited, and examples thereof include a method of cooling by introducing a refrigerant from the outside of the reaction vessel, and a method of cooling by directly introducing cold water into the reaction system.

[Solid-liquid separation and washing process]
In this solid-liquid separation / washing step, a solid-liquid separation process for solid-liquid separation of the toner base from the dispersion of the toner base cooled to a predetermined temperature in the above-described step, and a solid-liquid separated toner cake (in a wet state) A cleaning process is performed to remove deposits such as a surfactant and a salting-out agent from an aggregate obtained by agglomerating a toner base in a cake form. Here, the filtration method is not particularly limited, such as a centrifugal separation method, a vacuum filtration method using Nutsche or the like, a filtration method using a filter press or the like.

[Drying process]
In this step, the washed toner cake is dried to obtain a dried toner base. Examples of dryers used in this process include spray dryers, vacuum freeze dryers, vacuum dryers, etc., stationary shelf dryers, mobile shelf dryers, fluidized bed dryers, rotary dryers It is preferable to use a stirring dryer or the like. The water content of the dried toner base is preferably 5% by mass or less, more preferably 2% by mass or less. In addition, when the toner bases subjected to the drying treatment are aggregated due to weak interparticle attraction, the aggregate may be crushed. Here, as the crushing treatment apparatus, a mechanical crushing apparatus such as a jet mill, a Henschel mixer, a coffee mill, or a food processor can be used.

[External process]
This step is a step in which an external additive is mixed with the dried toner base as necessary to produce a toner.

  As an external additive mixing device, a mechanical mixing device such as a Henschel mixer or a coffee mill can be used.

  Next, the compounds constituting the toner (binder resin, colorant, release agent, charge control agent, external additive) will be described.

(Binder resin)
As the polymerizable monomer for forming the resin particles A and the resin particles B constituting the binder resin, known monomers can be used. Specifically, it is preferable to use a combination of styrene, acrylic acid or methacrylic acid derivatives, and those having an ionic dissociation group.

  As the polymerizable monomer constituting the resin particles, styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, α-methylstyrene, p-chlorostyrene, 3,4-dichlorostyrene are used. , P-phenylstyrene, p-ethylstyrene, 2,4-dimethylstyrene, p-tert-butylstyrene, pn-hexylstyrene, pn-octylstyrene, pn-nonylstyrene, pn- Styrene or styrene derivatives such as decyl styrene, pn-dodecyl styrene, methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, isopropyl methacrylate, isobutyl methacrylate, t-butyl methacrylate, n-octyl methacrylate , 2-ethylhexyl methacrylate, stearyl methacrylate Methacrylic acid ester derivatives such as lauryl methacrylate, phenyl methacrylate, diethylaminoethyl methacrylate, dimethylaminoethyl methacrylate, methyl acrylate, ethyl acrylate, isopropyl acrylate, n-butyl acrylate, t-butyl acrylate, acrylic Acrylates such as isobutyl acid, n-octyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, lauryl acrylate, phenyl acrylate, olefins such as ethylene, propylene, isobutylene, vinyl chloride, vinylidene chloride, Halogenated vinyls such as vinyl bromide, vinyl fluoride and vinylidene fluoride, vinyl esters such as vinyl propionate, vinyl acetate and vinyl benzoate, vinyl methyl ether, vinyl ethyl ether Vinyl ethers such as ether, vinyl ketones such as vinyl methyl ketone, vinyl ethyl ketone, vinyl hexyl ketone, N-vinyl compounds such as N-vinyl carbazole, N-vinyl indole, N-vinyl pyrrolidone, vinyl naphthalene, vinyl pyridine, etc. Examples include vinyl compounds, acrylic acid or methacrylic acid derivatives such as acrylonitrile, methacrylonitrile, and acrylamide. These vinyl monomers can be used alone or in combination.

  Further, it is more preferable to use a combination of monomers having an ionic dissociation group as the polymerizable monomer constituting the resin. For example, it has a substituent such as a carboxyl group, a sulfonic acid group, a phosphoric acid group as a constituent group of the monomer, specifically, acrylic acid, methacrylic acid, maleic acid, itaconic acid, cinnamic acid, fumar Acid, maleic acid monoalkyl ester, itaconic acid monoalkyl ester, styrene sulfonic acid, allyl sulfosuccinic acid, 2-acrylamido-2-methylpropane sulfonic acid, acid phosphooxyethyl methacrylate, 3-chloro-2-acid phosphooxy And propyl methacrylate.

  Furthermore, multifunctional such as divinylbenzene, ethylene glycol dimethacrylate, ethylene glycol diacrylate, diethylene glycol dimethacrylate, diethylene glycol diacrylate, triethylene glycol dimethacrylate, triethylene glycol diacrylate, neopentyl glycol dimethacrylate, neopentyl glycol diacrylate, etc. It is also possible to use a crosslinkable resin by using a functional vinyl.

  These polymerizable monomers can be polymerized using a radical polymerization initiator. In this case, an oil-soluble polymerization initiator can be used in the suspension polymerization method. Examples of the oil-soluble polymerization initiator include 2,2′-azobis- (2,4-dimethylvaleronitrile), 2,2′-azobisisobutyronitrile, 1,1′-azobis (cyclohexane-1-carboxyl). Nitriles), 2,2'-azobis-4-methoxy-2,4-dimethylvaleronitrile, azo- or diazo-based polymerization initiators such as azobisisobutyronitrile, benzoyl peroxide, methyl ethyl ketone peroxide, diisopropyl peroxycarbonate , Cumene hydroperoxide, t-butyl hydroperoxide, di-t-butyl peroxide, dicumyl peroxide, 2,4-dichlorobenzoyl peroxide, lauroyl peroxide, 2,2-bis- (4,4- t-butylperoxycyclohexyl) propane, tris- Peroxide polymerization initiator or a peroxide such as t- butylperoxy) triazine and the like polymeric initiator having a side chain.

  Moreover, when using an emulsion polymerization method, a water-soluble radical polymerization initiator can be used. Examples of the water-soluble polymerization initiator include persulfates such as potassium persulfate and ammonium persulfate, azobisaminodipropane acetate, azobiscyanovaleric acid and its salts, hydrogen peroxide and the like.

  For the formation of the resin particles B, it is preferable to use a combination of polymerizable monomers that have a glass transition temperature (Tg) higher than that of the resin particles A.

  The glass transition temperature (Tg) according to the present invention is measured using a differential scanning calorimeter “DSC-7” (Perkin Elmer) and a thermal analyzer control “TAC7 / DX” (Percon Elmer). be able to.

  As an operation procedure, 4.5 to 5.0 mg of a measurement sample is precisely weighed to two digits after the decimal point, sealed in an aluminum pan (Kit No. 0219-0041), and set in a “DSC-7 sample holder”. The reference used an empty aluminum pan. The measurement conditions were a measurement temperature of 0 to 200 ° C., a temperature increase rate of 10 ° C./min, a temperature decrease rate of 10 ° C./min, and heat-cool-heat temperature control. Analysis was performed based on the data in Heat.

  The glass transition temperature is obtained by drawing an extension of the baseline before the rise of the first endothermic peak and a tangent line indicating the maximum slope between the rise portion of the first peak and the peak apex, and using the intersection as the glass transition point. Show.

(Coloring agent)
As the colorant used in the present invention, a known inorganic or organic colorant can be used. Specific colorants are shown below.

  Examples of the black colorant include carbon black such as furnace black, channel black, acetylene black, thermal black, and lamp black, and magnetic powder such as magnetite and ferrite.

  Examples of the colorant for magenta or red include C.I. I. Pigment red 2, C.I. I. Pigment red 3, C.I. I. Pigment red 5, C.I. I. Pigment red 6, C.I. I. Pigment red 7, C.I. I. Pigment red 15, C.I. I. Pigment red 16, C.I. I. Pigment red 48; 1, C.I. I. Pigment red 53: 1, C.I. I. Pigment red 57: 1, C.I. I. Pigment red 122, C.I. I. Pigment red 123, C.I. I. Pigment red 139, C.I. I. Pigment red 144, C.I. I. Pigment red 149, C.I. I. Pigment red 166, C.I. I. Pigment red 177, C.I. I. Pigment red 178, C.I. I. And CI Pigment Red 222.

  Examples of the colorant for orange or yellow include C.I. I. Pigment orange 31, C.I. I. Pigment orange 43, C.I. I. Pigment yellow 12, C.I. I. Pigment yellow 13, C.I. I. Pigment yellow 14, C.I. I. Pigment yellow 15, C.I. I. Pigment yellow 74, C.I. I. Pigment yellow 93, C.I. I. Pigment yellow 94, C.I. I. And CI Pigment Yellow 138.

  Examples of the colorant for green or cyan include C.I. I. Pigment blue 15, C.I. I. Pigment blue 15; 2, C.I. I. Pigment blue 15; 3, C.I. I. Pigment blue 15; 4, C.I. I. Pigment blue 16, C.I. I. Pigment blue 60, C.I. I. Pigment blue 62, C.I. I. Pigment blue 66, C.I. I. And CI Pigment Green 7.

  These colorants may be used alone or in combination of two or more as required. The addition amount of the colorant is set in the range of 1 to 30% by mass, preferably 2 to 20% by mass with respect to the whole toner.

(Release agent)
A known compound can be used as the release agent used in the present invention.

  As such, for example, polyolefin wax such as polyethylene wax and polypropylene wax, long chain hydrocarbon wax such as paraffin wax and sazol wax, dialkyl ketone wax such as distearyl ketone, carnauba wax, montan wax, Trimethylolpropane tribehenate, pentaerythritol tetrabehenate, pentaerythritol diacetate dibehenate, glycerin tribehenate, 1,18-octadecanediol distearate, merit acid tristearyl, distearyl maleate, etc. And amide waxes such as ethylenediamine behenyl amide and trimellitic acid tristearyl amide.

  The amount of the release agent contained in the toner is preferably 1 to 20% by mass and more preferably 3 to 15% by mass with respect to the whole toner.

(Charge control agent)
A charge control agent can be added to the toner of the present invention as necessary. A known compound can be used as the charge control agent.

(External additive)
Examples of inorganic particles that can be used as an external additive include conventionally known particles. Specifically, silica fine particles, titanium fine particles, alumina fine particles, and complex oxides thereof can be preferably used. These inorganic particles are preferably hydrophobic.

  Examples of organic fine particles that can be used as an external additive include spherical fine particles having a number average primary particle size of about 10 to 2000 nm. Examples of the constituent material of the organic fine particles include polystyrene, polymethyl methacrylate, and styrene-methyl methacrylate copolymer.

<Developer>
The toner of the present invention can be used as a one-component developer or a two-component developer.

  When used as a one-component developer, a non-magnetic one-component developer or a magnetic one-component developer containing about 0.1 μm to 0.5 μm of magnetic particles in the toner can be used. be able to.

  Further, it can be mixed with a carrier and used as a two-component developer. As the carrier, conventionally known magnetic particles such as metals such as iron, ferrite, and magnetite, and alloys of these metals with metals such as aluminum and lead can be used. Ferrite particles are particularly preferable. The particle diameter of the carrier is preferably 20 to 100 μm, and more preferably 25 to 80 μm.

  The particle diameter of the carrier can be typically measured by a laser diffraction particle size distribution measuring apparatus “HELOS” (manufactured by SYMPATEC) equipped with a wet disperser.

  The carrier is preferably a carrier in which magnetic particles are further coated with a resin, or a so-called resin dispersion type carrier in which magnetic particles are dispersed in a resin. The coating resin is not particularly limited, and for example, an olefin resin, a styrene resin, a styrene-acrylic resin, a silicon resin, an ester resin, a fluorine-containing polymer resin, or the like is used. The resin for constituting the resin-dispersed carrier is not particularly limited, and known resins can be used. For example, styrene-acrylic resin, polyester resin, fluorine resin, phenol resin, etc. are used. be able to. Among these, a coat carrier coated with a styrene-acrylic resin is more preferable because it can prevent the external additive from being detached and ensure durability.

<Image formation>
The toner of the present invention is suitably used in a contact-type fixing type image forming apparatus that fixes a transfer material on which a toner image is formed by passing between heating members constituting the fixing apparatus.

  Hereinafter, the image forming apparatus and the fixing apparatus will be described.

  FIG. 4 is a schematic view showing an example of an image forming apparatus used in the image forming method according to the present invention.

  In FIG. 4, 1Y, 1M, 1C and 1K are photoreceptors, 4Y, 4M, 4C and 4K are developing means, 5Y, 5M, 5C and 5K are primary transfer rolls as primary transfer means, and 5A is a secondary transfer. Secondary transfer rolls as means, 6Y, 6M, 6C and 6K are cleaning means, 7 is an intermediate transfer member unit, 24 is a heat roll type fixing device, and 70 is an intermediate transfer member.

  This image forming apparatus is called a tandem color image forming apparatus, and includes a plurality of sets of image forming units 10Y, 10M, 10C, and 10K, an endless belt-shaped intermediate transfer body unit 7 as a transfer unit, and a recording member P. An endless belt-shaped paper feeding and conveying means 21 and a heat roll type fixing device 24 as a fixing means. A document image reading device SC is disposed on the upper part of the main body A of the image forming apparatus.

  As one of the different color toner images formed on each photoconductor, an image forming unit 10Y that forms a yellow image includes a drum-shaped photoconductor 1Y as a first photoconductor, and a periphery of the photoconductor 1Y. A charging unit 2Y, an exposure unit 3Y, a developing unit 4Y, a primary transfer roll 5Y as a primary transfer unit, and a cleaning unit 6Y. An image forming unit 10M that forms a magenta image as another different color toner image is disposed around a drum-shaped photoconductor 1M as a first photoconductor, and the photoconductor 1M. A charging unit 2M, an exposure unit 3M, a developing unit 4M, a primary transfer roll 5M as a primary transfer unit, and a cleaning unit 6M. In addition, an image forming unit 10C that forms a cyan image as one of other different color toner images is disposed around the photoconductor 1C as a drum-type photoconductor 1C as a first photoconductor. The charging unit 2C, the exposure unit 3C, the developing unit 4C, the primary transfer roll 5C as the primary transfer unit, and the cleaning unit 6C are provided. Further, an image forming unit 10K that forms a black image as one of other different color toner images is disposed around a drum-shaped photosensitive member 1K as a first photosensitive member, and the photosensitive member 1K. It has a charging means 2K, an exposure means 3K, a developing means 4K, a primary transfer roll 5K as a primary transfer means, and a cleaning means 6K.

  The endless belt-like intermediate transfer body unit 7 has an endless belt-like intermediate transfer body 70 as an intermediate transfer endless belt-like second image carrier that is wound around a plurality of rolls and is rotatably supported.

  Each color image formed by the image forming units 10Y, 10M, 10C, and 10K is sequentially transferred onto the rotating endless belt-shaped intermediate transfer body 70 by the primary transfer rolls 5Y, 5M, 5C, and 5K, and is combined. A colored image is formed. A recording member P such as a sheet as a transfer material accommodated in the sheet feeding cassette 20 is fed by the sheet feeding / conveying means 21, passes through a plurality of intermediate rolls 22 A, 22 B, 22 C, 22 D, and a registration roll 23, and is secondary. A color image is transferred onto the recording member P at a time by being conveyed to a secondary transfer roll 5A as a transfer means. The recording member P to which the color image has been transferred is fixed by the heat roll type fixing device 24, is sandwiched by the paper discharge roll 25, and is placed on the paper discharge tray 26 outside the apparatus.

  On the other hand, after the color image is transferred to the recording member P by the secondary transfer roll 5A, the residual toner is removed from the endless belt-shaped intermediate transfer body 70 from which the recording member P is separated by the curvature by the cleaning means 6A.

  During the image forming process, the primary transfer roll 5K is always in pressure contact with the photoreceptor 1K. The other primary transfer rolls 5Y, 5M, and 5C are in pressure contact with the corresponding photoreceptors 1Y, 1M, and 1C, respectively, only during color image formation.

  The secondary transfer roll 5A is pressed against the endless belt-shaped intermediate transfer body 70 only when the recording member P passes through the secondary transfer roll 5A and the secondary transfer is performed.

  Further, the housing 8 can be pulled out from the apparatus main body A through the support rails 82L and 82R.

  The housing 8 includes image forming units 10Y, 10M, 10C, and 10K, and an endless belt-shaped intermediate transfer body unit 7.

  The image forming units 10Y, 10M, 10C, and 10K are arranged in tandem in the vertical direction. An endless belt-shaped intermediate transfer body unit 7 is disposed on the left side of the photoreceptors 1Y, 1M, 1C, and 1K in the figure. The endless belt-shaped intermediate transfer body unit 7 includes an endless belt-shaped intermediate transfer body 70 that can be rotated by winding rolls 71, 72, 73, 74, and 76, primary transfer rolls 5Y, 5M, 5C, and 5K, and a cleaning unit. 6A.

  The image forming units 10Y, 10M, 10C, and 10K and the endless belt-shaped intermediate transfer body unit 7 are integrally pulled out from the main body A by the drawer operation of the housing 8.

  In this way, toner images are formed on the photoreceptors 1Y, 1M, 1C, and 1K by charging, exposure, and development, and the toner images of the respective colors are superimposed on the endless belt-shaped intermediate transfer body 70, and are collectively applied to the recording member P. The image is transferred, and fixed by pressing and heating with a heat roll type fixing device 24 and fixed. The photoreceptors 1Y, 1M, 1C, and 1K after transferring the toner image to the recording member P are cleaned with the cleaning device 6A to remove the toner remaining on the photoreceptor, and then the above-described charging, exposure, and development cycle. The next image formation is performed.

  FIG. 5 is a cross-sectional view showing an example of a fixing device (a type using a pressure roll and a heating roll) used in the present invention.

  The fixing device 10 shown in FIG. 5 includes a heating roll 71 and a pressure roll 72 in contact with the heating roll 71. In FIG. 5, 90 is a separation claw, and 17 is a toner image formed on a transfer material (transfer paper) P.

  The heating roll 71 has a coating layer 82 made of a fluororesin or an elastic body formed on the surface of the cored bar 81 and includes a heating member 75 made of a linear heater.

  The cored bar 81 is made of metal and has an inner diameter of 10 to 70 mm. Although it does not specifically limit as a metal which comprises the metal core 81, For example, metals, such as iron, aluminum, copper, or these alloys can be mentioned.

  The thickness of the cored bar 81 is 0.1 to 15 mm, and is determined in consideration of a balance between a request for energy saving (thinning) and strength (depending on the constituent materials). For example, in order to maintain the same strength as that of a cored bar made of iron of 0.57 mm with a cored bar made of aluminum, the wall thickness needs to be 0.8 mm.

  Examples of the fluororesin constituting the surface of the coating layer 82 include PTFE (polytetrafluoroethylene) and PFA (tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer).

  The thickness of the coating layer 82 made of a fluororesin is 10 to 500 μm, preferably 20 to 400 μm.

  When the thickness of the coating layer 82 made of the fluororesin is less than 10 μm, the function as the coating layer cannot be sufficiently exhibited, and the durability as the fixing device cannot be ensured. On the other hand, there is a problem that the surface of the coating layer exceeding 500 μm is easily scratched by paper dust, and toner or the like adheres to the scratched part, thereby causing image smearing.

  Further, as the elastic body constituting the covering layer 82, it is preferable to use silicon rubber, silicon sponge rubber or the like having good heat resistance such as LTV, RTV, HTV.

  The Asker C hardness of the elastic body constituting the covering layer 82 is less than 80 °, preferably less than 60 °.

  The thickness of the coating layer 82 made of an elastic body is preferably 0.1 to 30 mm, and more preferably 0.1 to 20 mm.

  As the heating member 75, a halogen heater can be preferably used.

  The pressure roll 72 is formed by forming a coating layer 84 made of an elastic body on the surface of the cored bar 83. The elastic body constituting the coating layer 84 is not particularly limited, and examples thereof include various soft rubbers such as urethane rubber and silicone rubber, and sponge rubber. The silicon rubber exemplified as the one constituting the coating layer 84 and It is preferable to use silicon sponge rubber.

  Moreover, 0.1-30 mm is preferable and, as for the thickness of the coating layer 84, 0.1-20 mm is more preferable.

  The fixing temperature (surface temperature of the heating roll 10) is preferably 70 to 180 ° C., and the fixing linear velocity is preferably 80 to 640 mm / sec. The nip width of the heating roll is set to 8 to 40 mm, preferably 11 to 30 mm.

  The separation claw 90 is provided to prevent the transfer material thermally fixed on the heating roll from being wound around the heating roll.

  The heating roll may be used by applying 0.3 mg or less of silicon oil per print, but may be used without oil.

  FIG. 6 is a schematic view showing an example of a fixing device (a type using a belt and a heating roll) used in the present invention.

  The fixing device 10 in FIG. 6 is a type using a belt and a heating roll to ensure a nip width, and the pressure pressed against the fixing roll 601 via the fixing roll 601, the seamless belt 11, and the seamless belt 11. The pad (pressure member) 12a, the pressure pad (pressure member) 12b, and the lubricant supply member 40 constitute a main part.

  The fixing roll 601 is formed by forming a heat-resistant elastic body layer 10b and a release layer (heat-resistant resin layer) 10c around a metal core (cylindrical core) 10a. A halogen lamp 14 is disposed as a heating source. The temperature of the surface of the fixing roll 601 is measured by the temperature sensor 15, and the halogen lamp 14 is feedback-controlled by a temperature control (not shown) based on the measurement signal so that the surface of the fixing roll 601 is adjusted to a constant temperature. The seamless belt 11 is in contact with the fixing roll 601 so as to be wound at a predetermined angle, thereby forming a nip portion.

  Inside the seamless belt 11, a pressure pad 12 having a low friction layer on its surface is disposed in a state of being pressed against the fixing roll 601 via the seamless belt 11. The pressure pad 12 is provided with a pressure pad 12a to which a strong nip pressure is applied and a pressure pad 12b to which a weak nip pressure is applied, and is held by a holder 12c made of metal or the like.

  Further, a belt traveling guide is attached to the holder 12c so that the seamless belt 11 can smoothly slide and rotate. The belt running guide is preferably a member having a low coefficient of friction because it rubs against the inner surface of the seamless belt 11, and a member having low thermal conductivity is preferred so that heat is not easily taken from the seamless belt 11.

  FIG. 7 is a schematic view showing an example of a fixing device (a type using a soft roll and a heating roll) used in the present invention.

  7 is a type using a soft roll and a heating roll that secures a fixing nip and prevents the transfer material from being wound and has excellent image quality. The heating roll 601 as a heating roll member, A soft roll 17b as a roll member is used, and a halogen lamp 14 as a heating member is provided inside the heating roll 601.

  A nip portion N is formed between the heating roll 601 and the soft roll 17b, and heat and pressure are applied through the nip portion N to fix the toner image on the transfer material P. In the above, a halogen lamp 14 (not shown) as a heating member may be disposed inside the soft roll 17b.

<Transfer material>
The transfer material used in the present invention is a support for holding a toner image, and is usually called an image support, a recording material, or transfer paper. Specifically, various transfer materials such as plain paper and fine paper from thin paper to thick paper, coated printing paper such as art paper and coated paper, commercially available Japanese paper and postcard paper, plastic film for OHP, cloth, etc. However, it is not limited to these.

  Examples of the present invention will be described below, but the present invention is not limited to these examples.

<Production of toner>
<Preparation of Toner Bk1>
(Preparation of resin particles A) Preparation of three-layer structure resin particles First stage polymerization Into a reaction vessel equipped with a stirrer, a temperature sensor, a cooling tube and a nitrogen introducing device, 8 g of sodium dodecyl sulfate was charged into 3000 g of ion-exchanged water, and nitrogen was added. The internal temperature was raised to 80 ° C. while stirring at a stirring speed of 230 rpm under an air flow. After the temperature rise, a solution of 10 g of potassium persulfate dissolved in 200 g of ion-exchanged water was added, the liquid temperature was again 80 ° C., the following monomer mixture was added dropwise over 1 hour, and then heated at 80 ° C. for 2 hours. Polymerization was performed by stirring to prepare resin particles. This is referred to as “resin particles (1H)”.

Styrene 480.0g
n-Butyl acrylate 250.0g
Methacrylic acid 68.0g
n-octyl-3-mercaptopropionate 16.0 g
Second stage polymerization A reaction vessel equipped with a stirrer, temperature sensor, condenser, and nitrogen introducing device was charged with a solution prepared by dissolving 7 g of polyoxyethylene (2) sodium dodecyl ether sulfate in 800 g of ion-exchanged water and brought to 98 ° C. After heating, 260 g of the resin particles (1H) and a solution prepared by dissolving the following monomer solution at 90 ° C. were added, and a mechanical disperser “CLEARMIX” having a circulation path (M Technique) For 1 hour to prepare a dispersion containing emulsified particles (oil droplets).

Styrene 245.0g
n-Butyl acrylate 120.0g
n-octyl-3-mercaptopropionate 1.5 g
Polyethylene wax (melting point 80 ° C) 190.0g
Next, an initiator solution in which 6 g of potassium persulfate is dissolved in 200 g of ion-exchanged water is added to this dispersion, and the system is heated and stirred at 82 ° C. for 1 hour to obtain resin particles. It was. This is referred to as “resin particles (1HM)”.

Third stage polymerization Furthermore, a solution in which 11 g of potassium persulfate was dissolved in 400 g of ion-exchanged water was added, and under a temperature condition of 82 ° C.,
435.0 g of styrene
n-Butyl acrylate 130.0g
Methacrylic acid 33.0 g
n-octyl-3-mercaptopropionate 8.0 g
A monomer mixture consisting of was added dropwise over 1 hour. After completion of the dropping, polymerization was carried out by heating and stirring for 2 hours, and then cooled to 28 ° C. to obtain resin particles. This is designated as “resin particle A”. The resin particles A had a Tg of 48 ° C. and a softening point of 88 ° C.

(Preparation of resin particle B)
Into a reaction vessel equipped with a stirrer, temperature sensor, condenser, and nitrogen introduction device, 2.3 g of sodium dodecyl sulfate was charged in 3000 g of ion-exchanged water, and the internal temperature was 80 ° C. while stirring at a stirring speed of 230 rpm under a nitrogen stream. The temperature was raised to. After heating, 10 g of potassium persulfate dissolved in 200 g of ion-exchanged water was added, the liquid temperature was again 80 ° C., the following monomer mixture was added dropwise over 1 hour, and then heated at 80 ° C. for 2 hours. Polymerization was carried out by stirring to prepare resin particles. This is designated as “resin particle B”. The resin particles B had a Tg of 53 ° C. and a softening point of 140 ° C.

Styrene 520.0g
n-Butyl acrylate 210.0g
Methacrylic acid 68.0g
n-octyl-3-mercaptopropionate 16.0 g
(Preparation of colorant dispersion)
90 g of sodium dodecyl sulfate was dissolved in 1600 g of ion-exchanged water with stirring. While stirring this solution, 420 g of carbon black “Regal 330R” (manufactured by Cabot Corp.) is gradually added, and then dispersed by using a stirrer “Claremix” (manufactured by M Technique Co., Ltd.). A dispersion of agent particles was prepared. This is designated as “colorant dispersion 1”. The particle diameter of the colorant particles in this colorant dispersion liquid 1 was 110 nm as measured using an electrophoretic light scattering photometer “ELS-800” (manufactured by Otsuka Electronics Co., Ltd.).

(Aggregation / fusion process)
In a reaction vessel equipped with a stirrer, a temperature sensor, a cooling pipe, and a nitrogen introducing device, 300 g of resin particles A, 1400 g of ion-exchanged water, 120 g of “colorant dispersion 1”, polyoxyethylene ( 2) A solution in which 3 g of sodium dodecyl ether sulfate was dissolved in 120 g of ion-exchanged water was added, the liquid temperature was adjusted to 30 ° C., and the pH was adjusted to 10 by adding a 5N aqueous sodium hydroxide solution. Next, an aqueous solution in which 35 g of magnesium chloride was dissolved in 35 g of ion-exchanged water was added over 10 minutes at 30 ° C. with stirring. After holding for 3 minutes, the temperature was raised and the system was heated to 90 ° C. over 60 minutes, and the particle growth reaction was continued while maintaining 90 ° C.

In this state, the particle size of the associated particles was measured with “Coulter Multisizer III” (manufactured by Beckman Coulter), and when the median particle size (D ₅₀ ) on the volume basis became 3.1 μm, the resin particles 260 g of B was added, and the particle growth reaction was continued. When the desired particle size is reached, an aqueous solution in which 150 g of sodium chloride is dissolved in 600 g of ion-exchanged water is added to stop particle growth, and further by heating and stirring at a liquid temperature of 98 ° C. as a fusion process, Fusion between the particles was allowed to proceed until the circularity was 0.965 as measured by “FPIA-2100” (manufactured by Sysmex Corporation). Thereafter, the solution was cooled to 30 ° C., hydrochloric acid was added to adjust the pH to 4.0, and stirring was stopped.

(Washing / drying process)
The particles produced in the aggregation / fusion process were solid-liquid separated with a basket type centrifugal separator “MARK III model number 60 × 40” (manufactured by Matsumoto Kikai Co., Ltd.) to form a toner base wet cake. The wet cake was washed with water using the basket-type centrifuge until the electric conductivity of the filtrate reached 5 μS / cm, and then transferred to a “flash jet dryer” (manufactured by Seishin Enterprise Co., Ltd.). %, And a toner base material having a median particle diameter (D ₅₀ ) of 6.2 μm on a volume basis was produced.

(External additive mixing process)
To the toner base obtained above, 1% by mass of hydrophobic silicon oxide (number average primary particle size = 12 nm, hydrophobicity = 68) and hydrophobic titanium oxide (number average primary particle size = 20 nm, hydrophobicity = 63) was added and mixed by “Henschel mixer” (manufactured by Mitsui Miike Chemical Co., Ltd.) to prepare “Toner Bk1”.

<Toners Bk2 to Bk11>
“Toners Bk2 to Bk11” were prepared in the same manner except that the addition amount and addition timing of the resin particles B were changed as shown in Table 1 in the aggregation / fusion process of the production of “Toner Bk1”.

The amount and timing of addition of the resin particles B used to prepare “Toners Bk1 to Bk11”, median particle diameter (D ₅₀ ), interfacial adhesion (Fr), internal cohesive force (Ft), and softening point based on volume The measurement results of (Tsp) are shown in Table 1. Tsp, Ft, and Fr were measured by the above measuring method.

<Preparation of Toners C1 to C11>
“Toner C1 to C11” was similarly used except that 420 g of “Legal 330R” (manufactured by Cabot) used in the production of “Toner Bk1 to Bk11” was changed to 210 g of “CI Pigment Blue 15: 3”. Was made.

<Preparation of Toners M1 to M11>
“Toners M1 to M11” were prepared in the same manner except that 420 g of “Legal 330R” (manufactured by Cabot) used in the production of “Toners Bk1 to Bk11” was changed to 357 g of “CI Pigment Red 122”. did.

<Preparation of Toners Y1 to Y11>
“Toners Y1 to Y11” were prepared in the same manner except that 420 g of “Regal 330R” (manufactured by Cabot) used in the production of “Toners Bk1 to Bk11” was changed to 378 g of “CI Pigment Yellow 74”. did.

  The measurement results for “toner 1 to C11”, “toner M1 to M11”, and “toner Y1 to Y11” are the same as the measurement results for “toner Bk1 to Bk11”, and therefore will be omitted.

<Production of developer>
Each of the above toners is mixed with a silicon carrier-coated ferrite carrier having a volume average particle diameter of 60 μm, and the developer density is 6% “Developers Bk1 to Bk11”, “Developers C1 to C11”, “Developer M1”. -M11 "and" Developers Y1-Y11 "were prepared.

《Live-action evaluation》
As the evaluation apparatus, the image forming apparatus shown in FIG. 4 was used with the fixing device shown in FIG. The fixing speed, the surface temperature of the heating roll, and the surface material of the heating roll were as follows.

Fixing speed: 280mm / sec (about 50 sheets / A4 size, landscape feed)
Surface temperature of heating roll: 120 ° C
Heat roll surface material: PTFE
The evaluation was carried out for the following evaluation items in an environment of 20 ° C. and 55% RH by sequentially loading the toner prepared above in the evaluation apparatus.

The print is an image with a pixel rate of 10% (original image with character image 7%, human face photo, solid white image, solid black image each 1/4), and A4 size high quality paper (64g / m ² ) went 1 million.

  In the evaluation, ◎, ○, and Δ were acceptable with no problems, and × were unacceptable with problems.

<Image defect>
Image defects such as black spots, black streaks, and white streaks due to toner filming and transfer omission were evaluated. The image defect was evaluated by visually observing images after the completion of printing 1 million sheets and evaluating the degree of occurrence of the image defect.

Evaluation criteria A: 1 or less black spots, no streak defect ○: 2 to 4 black spots, no streak defect ×: 5 or more black spots, streak defect

<Winding around fixing (heating) roll>
The fixing separation claw of the evaluation device was removed, and the winding of the transfer material around the hot roll was evaluated.

Wrapping around the heating roll is evaluated in the state where the transfer material is wound around the heating roll when 100 sheets of solid images are printed on the top edge of the print 5 cm by feeding A4 size high-quality paper (64 g / m ² ). did.

Evaluation Criteria A: No winding of 100 sheets occurred, and no transfer material adhered to the heating roll, and no lifting phenomenon was observed. O: No winding of 100 sheets occurred, but the transfer material adhered to the heating roll. Lifting phenomenon was observed in 1 to 3 sheets Δ: No winding occurred in all 100 sheets, but a phenomenon in which the transfer material adhered to the heating roll and lifted up was observed in 4 or more sheets ×: Winding occurred.

  Table 2 shows the evaluation results.

  As is apparent from the evaluation results shown in Table 2, “Toners 1 to 7” of “Examples 1 to 7” are excellent in all evaluation items, but “Toners 8 to 11” of “Comparative Examples 1 to 4”. "" Indicates that there are problems with some of the evaluation items.

It is a schematic diagram which shows an example of the measuring apparatus which measures interface adhesion force (Fr) and internal cohesion force (Ft). It is a schematic diagram of the head which measures interface adhesive force (Fr). It is a schematic diagram of the head which measures internal cohesion force (Ft). 1 is a schematic diagram illustrating an example of an image forming apparatus used in an image forming method according to the present invention. It is sectional drawing which shows an example of the fixing device (The type using a pressure roll and a heating roll) used for this invention. It is the schematic which shows an example of the fixing device (type using a belt and a heating roll) used for this invention. It is the schematic which shows an example of the fixing device (The type using a soft roll and a heating roll) used for this invention.

Explanation of symbols

11 Lifting shaft 12 Load cell 13 Heat insulation member 14 Heating member (panel heater)
DESCRIPTION OF SYMBOLS 15 Head part 17 Holding member 18 Toner pellet contact surface 19 Contact surface 20 Attaching member 21 Spring 22 Base 23 Data input device 24 Analyzing device 31 Fr measurement head part 32 Cylindrical head 33 Thermocouple 34 Heat resistant double-sided tape 35 PTFE coated member 41 Ft measurement head part 42 Cylinder type head 43 Head with 9 points

Claims (5)

In the electrostatic image developing toner containing at least a binder resin and a colorant, the interfacial adhesive force (Fr) between the electrostatic image developing toner and polytetrafluoroethylene is 1.0 to 3.5 N. An electrostatic charge image developing toner, wherein the electrostatic charge image developing toner has an internal cohesive force (Ft) of 10 to 18 N. The toner for developing an electrostatic charge image according to claim 1, wherein the toner for developing an electrostatic charge image has a softening point of 90 to 115 ° C. An electrostatic charge image developing toner manufacturing method having an aggregation step, wherein the resin particles B are added during the aggregation step of the resin particles A, and the aggregation is further advanced to complete the aggregation. Toner manufacturing method. An image forming method comprising a step of forming a toner image using the electrostatic image developing toner according to claim 1. An image forming apparatus using the image forming method according to claim 4.

Images