JP3151675B2 - Manufacturing method of toner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a toner used for developing an electrostatic image in, for example, electrophotography, electrostatic recording, electrostatic printing, and the like.

[0002]

2. Description of the Related Art In an example of electrophotography, an electrostatic image is formed on a photoconductive photoreceptor by charging and exposure, and the electrostatic image is developed with toner to form a toner image.
Next, the toner image is transferred to a transfer material and fixed to form a visible image. On the other hand, toner remaining on the photoreceptor without being transferred to the transfer material is cleaned by cleaning means such as a blade. A toner applied to such an electrophotographic method needs to have high cleaning properties and appropriate polishing properties. That is, when the cleaning property of the toner is low, the image is stained by the toner remaining on the surface of the photoconductor without being cleaned.
Also, if the abrasiveness of the toner is too high, the surface of the photoreceptor is damaged, and the toner material is embedded in the damaged portion, resulting in dot-like stains (black spots) on the image at the time of forming the next image. Appear. On the other hand, if the abrasiveness of the toner is too low, the toner substance gradually adheres and accumulates on the surface of the photoreceptor, and the electrical characteristics of the photoreceptor deteriorate.

Conventionally, the following techniques have been proposed as techniques relating to the cleaning and polishing properties of toner. A technique in which an acrylic polymer fine powder having a smaller diameter than the toner powder is added to and mixed with the toner powder.
0-188851). A technique of adding and mixing a binder resin powder with a composite fine powder obtained by fixing an inorganic fine powder on the surface of a resin fine powder having a smaller diameter by a mechanical impact force (JP-A-64-91143, 2-464
No. 69).

[0004]

However, according to the above-mentioned technique, sufficient abrasiveness cannot be exhibited because the hardness of the acrylic polymer fine powder is low. Therefore, there is a problem that the surface of the photoreceptor is filmed by the toner substance as the image formation is repeated, and the electrical characteristics of the photoreceptor are deteriorated early. Further, in the above technique, when the pressing force of the cleaning blade against the surface of the photoconductor is increased in order to prevent filming of the photoconductor by the toner substance, the blade is greatly deformed and its durability is significantly reduced. . In addition, according to the above-mentioned technology, when the inorganic fine powder is not sufficiently fixed to the surface of the resin fine powder, the inorganic fine powder is released from the composite fine powder by mechanical stirring or the like in a developing device, and the cleaning property is improved. Drop,
Also, the surface of the photoreceptor is damaged by the released inorganic fine powder, and the inorganic fine powder is embedded in the damaged portion of the surface of the photoreceptor so that it is not cleaned. As a result, the embedded inorganic powder is formed in the next image formation. There is a problem that the toner adheres to the fine powder and is fixed, thereby causing black streak-like stains or black spots on the image. Further, when the released inorganic fine powder adheres to the binder resin powder, there is a problem that the chargeability of the toner is significantly changed and the image density is reduced.

Accordingly, the present inventor has conducted intensive studies on a technique for preventing the release of inorganic fine particles from composite fine particles that function as a so-called cleaning aid. The fixation rate is an important factor, and by setting the fixation rate to 25% or more and less than 100%, more preferably 40% or more and less than 100%, the fixation of the inorganic fine particles becomes sufficient.
Knowledge that inorganic fine particles are not released even when an image is formed many times, no cleaning failure occurs due to damage of the photoreceptor due to the inorganic fine particles, and the image density does not decrease due to change in chargeability Based on the above, it has been found that the temperature of the product when applying the impact force to the mixture of the resin particles and the inorganic fine particles is important in order to define the fixation rate as described above, and completed the present invention. It is. The present invention has been made based on the above circumstances,
An object of the present invention is to provide a method capable of producing a toner having excellent cleaning properties and charge stability without releasing inorganic fine particles from composite fine particles.

[0006]

Means for Solving the Problems To achieve the above object, the present invention provides a method for producing a composite particle comprising at least a resin and a colorant, and a composite particle comprising inorganic resin particles fixed on the surface of the resin particle. When the resin particles and the inorganic fine particles are made into a uniform mixture and the softening point of the resin particles is Tsp (° C.) and the glass transition point is Tg (° C.) , In a mixer set so that the temperature T (° C.) satisfies the following equation, the mixture is repeatedly given an impact force to apply fine particles to the surface of the resin particles.
The method is characterized by producing composite fine particles having a sticking rate of the particles of 25% or more and less than 100% . Tg ≦ T ≦ Tsp-70

[0007]

In the present invention, the product temperature T when applying a shock to a uniform mixture of resin particles and inorganic fine particles is determined by taking into account the softening point Tsp and glass transition point Tg of the resin particles. As a result, the fixing rate of the inorganic fine particles to the surface of the resin particles can be reliably maintained at a level of 25% or more and less than 100%, and moreover, the composite fine particles can be obtained in a stable and high yield. The fixing process of the inorganic fine particles on the resin particle surface is not necessarily clear, but is considered as follows. That is, in a mixed state in which the inorganic fine particles are completely adhered to the resin particles and no free excessive particles are present, in the case of a homogeneous mixture mixed in a so-called ordered mixture state, the inorganic fine particles adhered on the resin particle surface Are rearranged while moving on the resin surface under the impact force, and are further fixed by collision with resin particles and adjacent inorganic fine particles and plastic deformation on the resin surface. If the product temperature T is set so as to satisfy the above equation, the plastic deformation on the resin surface occurs moderately, and the above process proceeds smoothly. As a result, the adhesion of the inorganic fine particles to the surface of the resin particles It is considered that the rate becomes a level of 25% or more and less than 100%. Therefore, even when an image is formed many times, release of the inorganic fine particles from the composite fine particles is prevented, and cleaning failure due to damage of the photoreceptor due to the inorganic fine particles does not occur, and an image due to a change in chargeability is not generated. No reduction in concentration occurs.

Hereinafter, the present invention will be described specifically. In the present invention, when producing the composite fine particles, the resin particles and the inorganic fine particles are made into a uniform mixture, and the mixture is repeatedly subjected to the impact force in a mixer set so that the product temperature T satisfies the above formula. give. If the product temperature T is lower than the lower limit of the above equation, that is, lower than the glass transition point Tg of the resin particles, plastic deformation of the surface of the resin particles hardly occurs, and the fixation rate is significantly reduced. On the other hand, if the product temperature T is higher than the upper limit of the above equation, that is, a temperature higher than (Tsp-70), the adhesiveness of the resin particles increases, and as a result, the resin particles are likely to aggregate and aggregate. Moreover, they are deposited on the inner wall of the mixer, and the yield is greatly reduced. Also, sufficient impact force is not applied to the fixation, and the fixation rate decreases.

The softening point Tsp is defined as 20% by a plunger while heating a 1 cm ³ sample at a heating rate of 6 ° C./min using a Koka type flow tester (manufactured by Shimadzu Corporation).
A nozzle having a diameter of 1 mm and a length of 1 mm was applied by applying a load of kg / cm ² , whereby the plunger descent-temperature curve (softening flow curve) of the flow tester was obtained.
And the temperature corresponding to h / 2 when the height of the S-shaped curve is h. Further, the glass transition point Tg refers to a value measured based on a differential scanning calorimetry (DSC), and specifically, using “DSC-20” (manufactured by Seiko Instruments Inc.), When measured at 10 ° C / min,
It refers to the temperature at the intersection of the extension of the baseline below the glass transition point and the tangent that shows the maximum slope from the peak rise to the peak apex.

By setting the product temperature T within the range of the above formula, the fixing rate of the inorganic fine particles to the resin particles in the composite fine particles is in the range of 25% or more and less than 100%. here,
The fixation rate was defined as the specific surface area of the resin particles Sa, the specific surface area of the inorganic fine particles Sb, the specific surface area of the composite fine particles after the inorganic fine particles were fixed on the surface of the resin particles Sh, and the addition rate of the inorganic fine particles x (%). Is defined by the following equation (1). However, the specific surface area is “Flowsorb 2300”
(Shimadzu Corporation), and the nitrogen adsorption specific surface area was measured by a one-point method based on the BET specific surface area measurement method.

[0011]

(Equation 1)

[0012] The range of the fixation rate is 25% or more and 100% or more.
It is less than 40%, but is particularly preferably 40% or more and 80% or less.
If the fixing rate is less than 25%, the fixing of the inorganic fine particles to the surface of the resin particles becomes insufficient, and the inorganic fine particles present on the surface of the composite fine particles are easily released. Therefore, when an image is formed many times, the release of the inorganic fine particles gradually increases, and a cleaning failure that adheres to the surface of the photoreceptor to form spot-like stains (black spots) occurs.
There is a problem that the chargeability of the developer is changed with time and the image density is reduced.

As the resin particles constituting the composite fine particles,
From the viewpoints of cleaning properties and triboelectrification, the average particle size is preferably 0.1 to 7 μm, and particularly preferably 0.2 to 7 μm.
5 μm is preferred. The average particle size of the resin particles refers to a volume-based average particle size, and is a laser diffraction particle size distribution analyzer “HELOS” (SYMPATE) equipped with a wet disperser.
(Manufactured by Company C). However, before the measurement, several tens of mg of the resin particles were added to water 50m together with the surfactant.
and then ultrasonic homogenizer (output 15
0W), a pretreatment of dispersing for 1 to 10 minutes was performed while paying attention to re-aggregation due to heat generation.

The resin material constituting the resin particles is not particularly limited, and various resins are used. For example, styrene, α-methylstyrene, styrene-based resin such as divinylbenzene, methyl methacrylate, ethyl methacrylate, butyl methacrylate, 2-ethylhexyl methacrylate, methyl acrylate, ethyl acrylate, acrylic resin such as butyl acrylate,
Styrene monomers such as styrene, α-methylstyrene and divinylbenzene and acrylic monomers such as methyl methacrylate, ethyl methacrylate, butyl methacrylate, 2-ethylhexyl methacrylate, methyl acrylate, ethyl acrylate and butyl acrylate Examples of the polymer include a styrene-acrylic copolymer, dimethylaminomethacrylate, diethylaminomethacrylate, and a nitrogen-containing resin containing vinylpyridine, a polyester resin, an epoxy resin, a nylon resin, a urethane resin, and a urea resin. The glass transition point Tg of the resin particles is preferably from 30 to 120 ° C, more preferably from 40 to 10 ° C, from the viewpoint of obtaining an excellent function as a cleaning aid.
0 ° C. is preferred. In addition, from the same viewpoint, the softening point Tsp of the resin particles is preferably from 100 to 200 ° C, and particularly preferably 12 to 200 ° C.
0-180 ° C is preferred.

Means for obtaining resin particles composed of the above resins include a method of synthesizing a monomer by a polymerization reaction such as emulsion polymerization or suspension polymerization, and a method of melting the resin itself by heat or the like. Examples thereof include a method of atomizing by spraying and a method of dispersing in water or the like to obtain a predetermined particle size. In the case where the resin particles are produced by a polymerization method, a so-called soap-free polymerization method is preferably used so that a surfactant or the like does not remain on the surface of the resin particles in order to stabilize the chargeability. A method of removing the suspension stabilizer may be used.

The inorganic fine particles constituting the composite fine particles preferably have an average particle diameter of 0.01 to 1 μm in terms of primary average particle diameter, and particularly preferably 0.01 to 1 μm, from the viewpoint of enhancing the cleaning property and the fixing property. ~ 0.5 μm is preferred. In addition, the primary average particle diameter of the inorganic fine particles refers to a number average particle diameter measured by image analysis observed with a scanning electron microscope. As the inorganic material constituting the inorganic fine particles, various inorganic oxides, carbides, nitrides, borides and the like are suitably used. For example, silica, alumina, titania, zirconia, barium titanate, aluminum titanate, strontium titanate, magnesium titanate, calcium titanate, zinc oxide, chromium oxide, cerium oxide, antimony oxide, tungsten oxide, tin oxide, tellurium oxide , Manganese oxide, boron oxide, silicon carbide, boron carbide, titanium carbide, silicon nitride, titanium nitride, titanium nitride, boron nitride and the like. Further, those obtained by subjecting the above compound to a hydrophobic treatment may be used.

As a method for fixing the inorganic fine particles on the surface of the resin particles, the resin particles and the inorganic fine particles are charged into a usual stirring device, for example, an OM dither, a turbular mixer, a Ladige mixer, a Henschel mixer, and the like. Then, the inorganic fine particles are electrostatically attached to the surface of the resin particles, and then the uniform mixture of the resin particles and the inorganic fine particles is transferred to a device improved from a usual impact-type pulverizer, and the impact force is applied to the mixture for 1 to 20 minutes. Over and over.

FIG. 1 shows an example of a processing apparatus suitably used for producing composite fine particles. 1 is a material input valve, 2 is a material input chute, 3 is a product discharge valve, 4 is a product discharge chute, 5 is a rotating disk (rotor), 6 is a blade (rotating blade) provided on the rotating disk 5, 7 is A stator, 8 is a recycling pipe, 9 is a jacket (can be cooled or heated), 10 is a casing, and 11 is a thermometer. The product thermometer 11 has a temperature measurement probe. This temperature measuring probe is composed of a chromel-alumel thermocouple, a resistance temperature detector, and the like, and can measure the temperature by electrically measuring the electromotive force, the resistance value, and the like. Also, the recycling pipe 8, the raw material input chute 2, and the product discharge chute 4 may be formed in a jacket structure to cool or heat. In this apparatus, while a uniform mixture of resin particles and inorganic fine particles sealed from the raw material charging valve 1 is rotated and dispersed by the turntable 5 and the blade 6,
The impact of the collision with the rotating disk 5, the blade 6 and the stator 7 and the collision of the particles causes the inorganic fine particles to be fixed to the surface of the resin particles.
By repeatedly receiving the impact force while circulating, the fixation is promoted. In FIG. 1, arrows indicate the trajectories of the raw material particles and the like.

Here, "product temperature" means that particles obtained by adhering inorganic fine particles to resin particles insert a temperature measuring probe into a particle population flowing by applying an impact force, and The average value of the approximate surface temperature of particles obtained by bringing particles into random contact with each other.
0cm, 6.4mm diameter stainless steel (SUS304)
-Alumel thermocouple with a stainless steel cover (Hayashi Electric Co., Ltd.)
The measurement was performed by inserting the end of the device 5 cm from the side wall of the apparatus, and the maximum temperature reached during the processing was defined as the product temperature T.

The amount of the inorganic fine particles added to the resin particles is
Any amount may be used as long as it can uniformly cover the surface of the resin particles. Specifically, although it differs depending on the specific gravity of the inorganic fine particles, from the viewpoint of improving the polishing effect by the composite fine particles and preventing the release of the inorganic fine particles, the amount is preferably 5 to 100 parts by weight with respect to 100 parts by weight of the resin particles, particularly 5 to 80 parts by weight are preferred. For example, when the addition amount of the inorganic fine particles is too small,
Since the surface of the composite fine particles becomes non-uniform and many resin portions are present on the surface, the polishing effect is likely to be reduced.

The amount of the composite fine particles added to the colored particles is as follows:
From the viewpoint of enhancing the cleaning property due to the polishing effect and not hindering the triboelectric charging property of the toner, it is preferable that the colorant particles have a particle size of 0.1%.
It is preferably from 0.01 to 5% by weight, particularly preferably from 0.01 to 2% by weight. It is also possible to add a fluidity improver such as hydrophobic silica or a fatty acid metal salt before use. When adding and mixing, it is preferable that the compound be present in a free state, not in a state of being fixed to the colored particles. When mixing, it is preferable to use a turbular mixer, Henschel mixer or the like.

The colored particles contain a binder resin, a colorant, and other additives used as needed.
The average particle size is usually in the range of 1 to 30 μm. The binder resin constituting the colored particles is not particularly limited,
Conventionally known various resins are used. For example, polyester resin, styrene / acrylic resin and the like are typical examples. As a coloring agent constituting the colored particles,
There is no particular limitation, and various conventionally known coloring agents are used. Examples include carbon black, nigrosine dye, aniline blue, calco oil blue, chrome yellow, ultramarine blue, Dupont oil red, quinoline yellow, methylene blue chloride, phthalocyanine blue, malachite green oxalate, lamp black, rose bengal, and the like.

Examples of other additives include charge control agents such as salicylic acid derivatives, and fixability improvers such as low molecular weight polyolefins. When a magnetic toner is obtained, magnetic particles are contained in the colored particles as an additive. The average particle diameter of the magnetic particles is 0.1 to 2 μm.
Particles of m, such as ferrite and magnetite, are used.
The amount of the magnetic particles added is usually in the range of 20 to 70% by weight of the colored particles excluding external additives such as composite fine particles.

Further, from the viewpoint of enhancing the fluidity of the toner,
In addition to the colored particles and the composite fine particles, inorganic fine particles may be further added from the outside to constitute the toner. As the inorganic fine particles, particularly, silica fine particles subjected to a hydrophobic treatment with a silane coupling agent, a titanium coupling agent or the like are preferable.

The toner produced by the production method of the present invention is mixed with a carrier to form a two-component developer,
Alternatively, when the toner is a magnetic toner, a one-component developer is formed by only the magnetic toner. As the carrier constituting the two-component developer, any of an uncoated carrier such as iron powder and a resin-coated carrier in which the surface of magnetic particles is coated with a resin can be used. The average particle size of the carrier is usually in the range of 30 to 150 μm.

The toner produced by the production method of the present invention can be used in combination with various conventionally known developing methods. Also, selenium-based photoconductors, organic photoconductive photoconductors (OPC photoconductors), amorphous silicon photoconductors (a-
It can be used in combination with various conventionally known photoconductors such as Si photoconductor.

[0027]

EXAMPLES Hereinafter, more specific examples will be described, but the present invention is not limited to these examples. In the following, MMA represents methyl methacrylate, BA represents butyl acrylate, BMA represents butyl methacrylate, and St represents styrene.

Example 1 Production of Composite Fine Particles Resin particles (St / BA (weight ratio: 8)
5/15) Copolymer particles, average particle size: 1.8 μm, BE
T specific surface area: 4.3 m ² / g, Tg: 62 ° C., Tsp:
162 ° C.) and 100 parts by weight of inorganic fine particles (aluminum oxide, average particle size: 0.02 μm, BET specific surface area: 4)
5.0 m ² / g) and 20 parts by weight were mixed with a high-speed stirring mixer for 10 minutes to obtain a uniform mixture in which inorganic fine particles were electrostatically adhered to the surface of the resin particles. Thereafter, the above mixture was mixed with "Hybridizer NHS-1" as shown in FIG.
Using a remodeling device (made by Nara Kikai Seisakusho), while circulating hot water, the product temperature is 64 ° C and the rotor speed is 8000r.
The mixture was treated for 10 minutes under the condition of pm to obtain composite fine particles A.
The fixing rate of the inorganic fine particles in the composite fine particles A is 36%.
Met. The yield of the composite fine particles A was 85%. [Production of colored particles] 60 parts by weight of a binder resin (St / MMA / BMA copolymer (weight ratio 75/5/20)), 30 parts by weight of magnetic powder (magnetite), 3 parts by weight of polypropylene, and charged A control agent (salicylic acid derivative) (0.5 part by weight) was mixed, ground, crushed, and classified to have an average particle size of 12.
Magnetic colored particles 1 of 0 μm were obtained. [Production of Toner] Hydrophobic silica (primary average particle size: 7 nm) was added to the magnetic colored particles 1 at a ratio of 0.4% by weight, and the composite fine particles A were added at a ratio of 0.7% by weight and mixed. Thus, a one-component magnetic toner 1 was produced, and this was used as a one-component developer.

Examples 2 to 4, Comparative Examples 1 and 2 In the production of the composite fine particles of Example 1, the product temperature was measured as shown in Table 1 below.
In the same manner, composite fine particle B
One-component magnetic toners 2 to 4 and one component for comparison were prepared in the same manner as in Example 1 except that C, D, a, and b were produced, and composite fine particles A were changed to each composite fine particle as shown in Table 4 below. Magnetic toners 1 and 2 were manufactured, and these were used as a one-component developer.

Example 5 [Production of composite fine particles] Resin particles (MMA / BA / St)
(Weight ratio 65/10/25) copolymer particles, average particle size:
2.0 μm, BET specific surface area: 3.9 m ² / g, Tg:
Example 1 using 100 parts by weight of 82 ° C., Tsp: 175 ° C.) and 15 parts by weight of inorganic fine particles (titanium oxide, average particle size: 0.015 μm, BET specific surface area: 56.0 m ² / g). Similarly, composite fine particles E were produced. The fixing ratio of the inorganic fine particles in the composite fine particles E was 42%. The yield of the composite fine particles E was 85%. [Production of colored particles] Binder resin (polyester resin) 10
0 parts by weight, 10 parts by weight of carbon black, and 4 parts by weight of polypropylene were mixed, kneaded, crushed, and classified to obtain nonmagnetic colored particles 2 having an average particle size of 11.0 μm. [Production of Toner] Hydrophobic silica (primary average particle size: 16 nm) was added to the colored particles 2 in an amount of 0.5% by weight, and the composite fine particles E were added and mixed in an amount of 1.0% by weight. 2
Component toner 5 was produced. [Production of developer] 3 parts by weight of the above toner and St / MM
A (3/7) resin-coated carrier (average particle size of 10) in which the surface of ferrite core particles is coated with a copolymer resin
(0 μm) was mixed to prepare a two-component developer.

Examples 6 to 8, Comparative Examples 3 and 4 Composite fine particles F, G, and H were prepared in the same manner as in Example 5 except that the resin particles and the inorganic fine particles were changed as shown in Table 2 below. , C, d, and
As in Example 5, two-component toners 6 to 8 and two-component toners for comparison 3 and 4 were produced in the same manner as in Example 5 except that the composite fine particles E were changed to each composite fine particle, and these toners were used. A two-component developer was produced in the same manner as in Example 5.

Examples 9 to 12 and Comparative Example 5 Composite fine particles I, J, K and L were prepared in the same manner as in Example 1 except that the resin particles and the inorganic fine particles were changed as shown in Table 3 below. , E, and Table 4
In the same manner as in Example 1 except that the composite fine particles A were changed to the composite fine particles as shown in FIG.
In addition, a one-component magnetic toner 5 for comparison was manufactured, and these were used as a one-component developer.

[0033]

[Table 1]

[0034]

[Table 2]

[0035]

[Table 3]

[0036]

[Table 4]

Using each developer obtained in the above Examples and Comparative Examples, the electrostatic image formed on the photoreceptor is developed to form a toner image, and this toner image is transferred to a transfer material. An image forming process including a step of fixing the transferred toner image and cleaning the toner remaining on the photoreceptor after the transfer with a cleaning blade was performed, and an actual printing test for forming a copy image was performed. The one-component developer is an electrophotographic copying machine for a one-component developer including a selenium (Se) photoreceptor, a non-contact type developing device for applying an oscillating electric field to a developing area, and a cleaning blade. Under a high-temperature high-humidity environment (HH environment) at a temperature of 33 ° C. and a relative humidity of 80%, and a low-temperature low-humidity environment (LL environment) at a temperature of 10 ° C. and a relative humidity of 15%. , Up to 100,000 times. Also,
For the two-component developer, arsenic selenium (As ₂ S
e ₃ ) Using an electrophotographic copying machine “U-Bix4060” (manufactured by Konica Corporation) for a two-component developer comprising a photoconductor, a developing device for a two-component developer, and a cleaning blade, H. Same as above. H environment and L. Under the L environment, a live-action test for forming a copy image up to 100,000 times was performed. The following items were evaluated by the actual shooting test described above. The results are shown in Table 5 below.

(1) Cleanability Under the L environment, a copy image was formed 100,000 times, and every 10,000 times, the surface of the photoreceptor after being cleaned by the cleaning blade was visually observed, and the presence or absence of attached matter was determined. The case where almost no deposits were observed was rated as “O”, the case where some deposits were observed but was at a practical level was rated as “Δ”, and the case where many deposits were observed and there was a problem in practice was rated “x”. (2) Black streak-like stains or black spots caused by deposits on the photoreceptor surface Under the L environment, a copy image is formed 100,000 times, and every 10,000 times, the surface of the photoreceptor after being cleaned by the cleaning blade is visually observed, and an image corresponding to a portion where an adhered substance is present. The number of copies when black streak-like stains or black spots began to occur on the portion was examined and evaluated. (3) Black streak-like stains or black spots due to scratches on the photoreceptor surface Under the L environment, a copy image is formed 100,000 times, and the surface of the photoreceptor is visually observed every 10,000 times. The number of copies when black stripe-like stains or black spots began to be generated was examined and evaluated. (4) Image density "Sakura Densitometer" in a live-action test conducted for 10 days at a rate of 10,000 times a day under the H environment
The maximum image density Dmax was measured and evaluated using Konica Corporation. ○ when the relative concentration is 1.25 or more,
The case where the value was 1.1 or more and less than 1.25 was rated as Δ, and the case where it was less than 1.1 was rated as x. (5) Fog H. "Sakura Densitometer" in a live shooting test under the H environment for 10,000 days / day at a pace of 10 days
(Manufactured by Konica Corporation) and the relative density of a white background portion where the document density was 0.0 was measured and judged. In addition, the white background reflection density was set to 0.0. ○ when the relative concentration is less than 0.01, Δ and 0.03 when the relative concentration is 0.01 or more and less than 0.03
The above case was evaluated as x.

[0039]

[Table 5]

[0040]

As described in detail above, according to the present invention, release of inorganic fine particles is sufficiently prevented, and a toner having excellent cleaning properties and charge stability can be produced.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing an example of a processing apparatus suitably used for producing composite fine particles.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Raw material input valve 2 Raw material input chute 3 Product discharge valve 4 Product discharge chute 5 Rotating disk (rotor) 6 Blade (rotating blade) 7 Stator 8 Recycling pipe 9 Jacket (Cooling or heating possible) 10 Casing 11 Thermometer

 ──────────────────────────────────────────────────続 き Continuing from the front page Judge Tetsuo Taki Judge Hiroshi Ueno Judge Hiroshi Shirosho (56) References JP-A-64-91143 (JP, A) JP-A-63-2075 (JP, A) JP-A-2-308262 (JP, A) JP-A-2-160032 (JP, A)

Claims (1)

(57) [Claims] 1. A method for producing a toner comprising: colored particles containing at least a resin and a colorant; and composite fine particles having inorganic fine particles adhered to the surface of the resin particles. A uniform mixture with inorganic fine particles,
When the softening point of the resin particles is Tsp (° C.) and the glass transition point is Tg (° C.) , the mixture is repeated in a mixer set so that the product temperature T (° C.) satisfies the following equation. By applying an impact force, the inorganic fine particles adhere to the surface of the resin particles.
A method for producing a toner, comprising producing composite fine particles having a deposition rate of 25% or more and less than 100% . Tg ≦ T ≦ Tsp-70