JP2002328488A - Method for producing polymerized toner - Google Patents

Abstract

(57) [Problem] To provide excellent low-temperature fixability and anti-offset property even when left for a long time under high temperature and high humidity, and to impair the developability (toner charge amount and image density) even when many sheets are used. To provide a method for producing a polymerized toner. A method for producing a polymerized toner obtained by polymerizing a polymerizable monomer composition containing at least a polymerizable monomer and a colorant, wherein a polymerization initiator is added a plurality of times,
And the polymerization initiator added after the second time is an organic peroxide, and at the time of addition of the polymerization initiator, the conversion of the polymerizable monomer is 70 to 95%, and And adding the polymerization initiator over 5 to 300 seconds.

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 polymerized toner used in electrophotography and electrostatic recording.

[0002]

2. Description of the Related Art Conventionally, many methods have been known as electrophotography. In general, a photoconductive substance is used to form an electric latent image on a photoreceptor by various means. The latent image is developed with a toner to form a visible image, the toner image is transferred to a transfer material such as paper as necessary, and then the toner image is fixed on the transfer material by heat, pressure, etc. Is what you get.

Various methods have been conventionally proposed as a method of developing with toner or a method of fixing a toner image.

Conventionally, toners used for these purposes are:
Generally, a colorant comprising a dye or a pigment is melt-kneaded in a thermoplastic resin, uniformly dispersed, then finely pulverized by a fine pulverizer, and the finely pulverized material is classified by a classifier to obtain a desired particle size. Has been manufactured.

[0005] Although this method can produce fairly good toners, it does have certain limitations, namely the choice of toner materials. For example, the resin colorant dispersion must be brittle enough to be pulverized in economically feasible manufacturing equipment. However, when the resin colorant dispersion is fragile to satisfy these requirements, when the dispersion is actually finely pulverized at a high speed, the particle size range of the formed particles tends to be widened, and in particular, a relatively large proportion of fine particles Is included in this. Further, the toner obtained from such a highly brittle material is liable to be further pulverized or powdered in a developing device such as a copying machine. Further, in this method, it is difficult to completely and uniformly disperse solid fine particles such as a colorant in a resin, and depending on the degree of the dispersion, an increase in fog at the time of image formation, a decrease in image density, color mixing or transparency. Because it causes poor sex
Great care must be taken in dispersing the colorant.
Further, exposure of the coloring agent to the fracture surface of the pulverized particles may cause a change in development characteristics.

On the other hand, in order to overcome the problems of the toner caused by these pulverization methods, Japanese Patent Publication Nos.
Various polymerization toners and production methods thereof have been proposed, including suspension polymerization toners disclosed in JP-A-3-10799 and JP-A-51-14895. For example, in a suspension polymerization method toner, a polymerizable monomer, a colorant and a polymerization initiator, and if necessary, a crosslinking agent, a charge control agent, and other additives are uniformly dissolved or dispersed to prepare a monomer composition. After, the medium containing the monomer composition containing a dispersion stabilizer,
For example, the toner particles are dispersed in an aqueous phase using a suitable stirrer, and simultaneously undergo a polymerization reaction to obtain toner particles having a desired particle size. In this method, since no pulverization step is included, the toner does not need to be brittle, a soft material can be used as the resin, and the colorant is not exposed on the particle surface, and uniform friction can be achieved. There is an advantage that a toner having chargeability can be obtained. Further, since the particle size distribution of the obtained toner is relatively sharp, even if the classification step is omitted or the classification is performed, the toner can be obtained in a high yield.

Further, in order to prevent the toner from adhering to the surface of the fixing roller, the surface of the roller is formed of a material having excellent releasability from the toner (silicone rubber, fluorine-based resin, etc.), and the surface is prevented from being offset. In order to prevent the roller surface from being fatigued, the roller surface is coated with a thin film of a liquid having high releasability such as silicone oil or fluorine oil. However, this method is extremely effective in preventing toner offset, but has a problem that a fixing device is complicated because a device for supplying an anti-offset liquid is required. Needless to say, this oil application causes delamination between the layers constituting the fixing roller, and consequently shortens the life of the fixing roller.

In view of this, instead of using a silicone oil supply device, instead of supplying the offset preventing liquid from the toner particles during heating, a releasing agent such as a low molecular weight polyethylene or a low molecular weight polypropylene is contained in the toner particles. Has been proposed.

It is known that wax is contained as a release agent in toner particles. For example, Japanese Patent Publication No. 52-33
04, JP-B-52-3305, JP-A-57
No. 52574.

Further, JP-A-3-50559, JP-A-2-79860, JP-A-1-109359, JP-A-62-14166, and JP-A-61-2
73554, JP-A-61-94062, JP-A-61-138259, and JP-A-60-2523
No. 61, JP-A-60-252360 and JP-A-60-217366 disclose that wax is contained in toner particles.

[0011] Wax is used for improving the anti-offset property at the time of low-temperature fixing or high-temperature fixing of the toner and for improving the fixing property at the time of low-temperature fixing. On the other hand, it lowers the blocking resistance of the toner, lowers the developability of the toner by raising the temperature inside the machine, and develops when the wax migrates to the surface of the toner particles when the toner is left for a long time under high temperature and high humidity. Or decrease the quality.

Toners produced by a suspension polymerization method have been proposed to solve the above problems. For example, JP-A-5-34
According to 1573, in a water-based dispersion medium, when a polar component is added to a monomer composition, a component having a polar group contained in the monomer composition is added to a surface layer portion at an interface with an aqueous phase. It is easy to exist, and the non-polar component hardly exists in the surface layer portion. Therefore, the toner particles can have a core / shell structure.

[0013] The toner produced by the suspension polymerization method can have both contradictory performances such as anti-blocking property and anti-high-temperature offset property by encapsulating wax in toner particles. It is possible to prevent high-temperature offset without applying a release agent as described above.

[0014] Japanese Patent Publication No. 7-82248,
Japanese Patent Application Laid-Open No. -120072 discloses a method for improving the fixability of a polymerized toner, in which a monomer composition is granulated in an aqueous medium, and then a polymerization initiator is added to the aqueous medium to perform suspension polymerization. Propose that. According to this method, it is possible to have a spherical and sharp particle size distribution and to contain a large amount of wax.

JP-A-10-239900 discloses that after a monomer composition is dispersed in an aqueous medium, a polymerization initiator is added to the aqueous medium, and further dispersed to prepare droplets. It proposes suspension polymerization.

Further, copiers or printers for forming full-color images have been used.

In the case of a fixing device in a color image forming apparatus, since a magenta toner, a cyan toner, a yellow toner, and a black toner are formed on a transfer material, a plurality of toner layers are formed. Tends to be easy.

As the transfer material on which the toner image is fixed, various papers, coated papers, plastic films and the like are generally used. In particular, the need for a transparency film (OHP film image) using an overhead projector for presentation is increasing. In particular, unlike paper, the OHP film has a low oil absorption capacity, so that a large amount of oil is present on the OHP film surface after fixing. Silicone oil evaporates due to heat and contaminates the inside of the image forming apparatus, and there is also a problem of processing collected oil.

However, in view of recent demands for miniaturization, weight reduction, and high reliability, it is preferable to remove even these auxiliary devices even in a full-color image forming apparatus, and a toner that can cope with such an auxiliary apparatus is desired.

In order to enhance the color mixing of the toner and to obtain a toner having excellent low-temperature fixability, it is preferable that the binder resin of the toner is instantaneously melted at the time of fixing. However, on the other hand, a binder resin having such properties is inferior in high-temperature offset resistance, blocking resistance, and durability.

[0021]

SUMMARY OF THE INVENTION An object of the present invention is to provide excellent low-temperature fixability and anti-offset properties even when left for a long period of time under high temperature and high humidity, and developability (toner charge amount) even when many sheets are used. , An image density) is provided.

An object of the present invention is to provide a method for producing a polymerized toner having a good charge amount of the toner and excellent transferability even when many sheets are used.

[0023]

Means for Solving the Problems The inventors of the present invention have made intensive studies to solve the above-mentioned problems, and have derived the present invention by paying attention to a technique of adding a polymerization initiator in plural times.

That is, the present invention relates to a method for producing a polymerized toner obtained by polymerizing a polymerizable monomer composition containing at least a polymerizable monomer and a colorant, wherein the polymerization initiator is used a plurality of times. The polymerization initiator to be added and added in the second and subsequent times is an organic peroxide, and the time of addition of the polymerization initiator added in the second and subsequent times depends on the conversion rate of the polymerizable monomer. Is 70 to 99%, and the polymerization initiator is added over 5 to 300 seconds.

[0025]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, it is important to add a polymerization initiator in plural times. This is because if the toner is added at once, a toner having the same molecular weight distribution as the vicinity of the surface layer of the obtained toner and the inside of the binder resin is obtained.

As described above, by adding a polar resin to the monomer composition, a non-polar component such as wax can be easily included in the toner, and as a result, excellent fixability and blocking resistance can be obtained. It is considered that a toner is obtained, but when the toner is left for a long time under a high temperature and a high humidity, a low softening point substance such as a wax included in the toner tends to migrate to the surface layer of the toner.

Therefore, the reaction is started with the polymerization initiator added the first time, and the second and subsequent polymerization initiators are added at the stage where the toner particles have been formed to some extent.

As the kind of the polymerization initiator for the second and subsequent times,
Organic substances are preferable in that the added polymerization initiator is easily adsorbed to the surface layer of the toner particles, and peroxides having strong hydrogen extraction ability are more preferable. Thereby, the resin in the surface layer of the toner particles is crosslinked in the course of the reaction, and as a result, a toner having a high strength only in the vicinity of the surface layer is obtained. When a crosslinking agent or the like is previously added to the monomer composition in order to obtain a sufficient surface layer strength, the entire binder resin is crosslinked, and it is difficult to increase the strength of only the surface layer. As a result, even if the surface layer strength is sufficient, the low-temperature fixability is impaired. However, a feature of the present invention is to increase the strength near the surface layer with respect to the inside of the toner, and a small amount of a crosslinking agent may be added in advance as long as the low-temperature fixability is not impaired. Specific examples of the crosslinking agent used include divinylbenzene, ethylene glycol diacrylate, ethylene glycol dimethacrylate, 1,3
-Butanediol dimethacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol diacrylate,
Examples thereof include 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, tripropylene glycol diacrylate, and polypropylene glycol diacrylate. These crosslinking agents may be used in combination.

Preferred organic peroxides used in the present invention include diacyl peroxides, specifically benzoyl peroxide, which have a good balance between the 10-hour half-life temperature and the hydrogen extraction ability. .

In the second addition of the polymerization initiator, the conversion of the polymerizable monomer is preferably from 70 to 99%, more preferably from 70 to 95%. If it is added at a stage where the conversion is less than 70%, a large amount of unreacted polymerizable monomer remains, and the crosslinking reaction easily proceeds inside the toner, which is not preferable. On the other hand, when it exceeds 99%, the amount of unreacted polymerizable monomer is small, so that it is insufficient to increase the strength sufficiently.

Further, it is preferable to raise the reaction temperature by 5 ° C. or more before or after the addition of the second polymerization initiator. It is considered that by raising the temperature by 5 ° C. or more, the molecular chains near the surface layer of the toner particles can be more easily moved, the reactivity near the surface layer increases, and the surface layer strength increases.

As a method of adding the polymerization initiator, 5
It is preferable to add over a period of about 300 seconds. It takes 5 to 300 seconds to add
When the polymerization initiator is supplied uniformly, the surface of each toner particle becomes uniform, so that the toner has good fixability, good fluidity of the toner, and good developability and transferability. Further, a toner having excellent durability, which does not easily fuse to members such as a carrier, a sleeve, and a blade, can be obtained.

When the polymerization initiator is added to the reaction system in less than 5 seconds, the added polymerization initiator tends to stay in one place, so that the polymerization initiator is uniformly applied to the surface of each toner particle. Is not easily supplied, and it is difficult to obtain uniformity of the surface of each toner particle, which is not preferable.

When the addition of the polymerization initiator exceeds 300 seconds, the polymerization initiator is uniformly supplied to the surface of each toner particle, but is gradually supplied to the surface of the toner particle little by little because the addition time is long. Will be. In the present invention, a predetermined amount of the polymerization initiator is uniformly adsorbed on the surface of each toner particle at a stretch to cause a reaction, so that the object can be achieved by imparting uniform strength to each toner particle surface, which is not preferable.

Further, the time T (second) required for adding the polymerization initiator and the number of passes N (times / second) per unit time of the stirring blade used for granulation are as follows: 10 ≦ T × N ≦ 1000 It is more preferable to satisfy the following relationship.

Here, the number of passes per unit time refers to the discharge amount per unit time of the stirring blade used for the reaction, and the total amount of the reaction system (for example, polymerization of the polymerizable monomer composition in an aqueous medium). In this case, the value is obtained by dividing by the total amount of the aqueous medium and the polymerizable monomer composition).

When the product of T and N is less than 10, the discharge amount of the stirring blade is small and the time required for addition of the polymerization initiator is short. In such a state, it is difficult to uniformly supply the polymerization initiator to the surface of each toner particle, and it is difficult to obtain surface uniformity of each toner particle, which is not preferable. On the other hand, when the product of T and N exceeds 1000, the discharge amount of the stirring blade is large and the time required for adding the polymerization initiator is long, so that the polymerization is uniformly started in each polymerizable monomer composition particle. Although the agent is supplied, coalescence of the particles is likely to occur, the generation of coarse particles tends to increase, and the particle size distribution becomes broad, which is not preferable.

The stirring blades used during the reaction include propeller blades, paddle blades, anchor blades, ribbon blades, Max Blend blades (manufactured by Sumitomo Heavy Industries), full zone blades (manufactured by Shinko Pantech) and the like. It is preferably used.

Further, the addition amount of the polymerization initiator added after the second time is changed to the addition amount of the polymerization initiator added at the first time.
The amount is preferably 1 to 50 parts by mass with respect to 0 parts by mass. When the amount is less than 1 part by mass, the amount of the polymerization initiator to be added is small, so that a sufficient reaction is not performed, and the surface strength of the toner becomes insufficient. Conversely, if it exceeds 50 parts by mass, the surface strength becomes too high, and the low-temperature fixability is impaired.

In the toner of the present invention, the THF-insoluble content of the polymerized toner is preferably 5 to 50% based on the polymerized toner. When the THF-insoluble content is less than 5%, the surface strength of the toner is insufficient. On the other hand, if it exceeds 50%, the surface layer strength is sufficient, but the low-temperature fixability decreases.

Further, it is preferable to contain 1 to 30 parts by mass of the low softening point substance based on 100 parts by mass of the polymerized toner. When the amount of the low softening point substance is less than 1 part by mass, the fixing property (offset resistance) cannot be obtained. Conversely, if the amount exceeds 30 parts by mass, the surface strength of the toner must be set to a considerably high level, and the low-temperature fixability decreases.

As the polar resin used in the present invention, a copolymer of styrene and (meth) acrylic acid, a maleic acid copolymer, a saturated polyester resin, and an epoxy resin are preferably used. Among these polar resins, polyester resins are particularly preferred. Further, it becomes possible to obtain a toner having a core / shell structure in which wax is included. This is because the toner is obtained by polymerization in an aqueous medium, the polar resin is likely to be localized on the toner surface layer, and low-polarity wax is pushed into the toner. It is considered that the polar resin present in the vicinity of the toner surface layer further reacts with the polymerization initiator added from the second time onward to obtain a surface layer strength that does not impair the low-temperature fixability.

The amount of the polar resin to be added is 0.1 to 100 parts by mass of the polymerizable monomer in the polymerizable monomer composition.
20 parts by weight are preferred. When the addition amount is less than 0.1 part by mass, the encapsulation of the wax described above becomes insufficient,
The effect of the present invention becomes insufficient. Further, even if the added amount exceeds 20 parts by mass, the effect of the present invention is not changed, and the granulation property of the toner particles is reduced, resulting in a distorted toner having a small average circularity. That is, according to the present invention, a toner having a high average circularity, an excellent wax encapsulation property, and a high surface strength can be obtained with a small amount of polar resin.

Further, the toner according to the present invention has an average circularity of 0.9 in a circle equivalent diameter-circularity scattergram based on the number of toners measured by a flow type particle image measuring apparatus.
It is preferably from 5 to 1.00. This is because the strength of the toner surface is made uniform, the stress resistance is excellent, and the developability and transferability are also improved.

As the low softening point substance used in the present invention, the wax is preferably a compound having a main maximum peak value of 40 to 110 ° C. measured according to ASTM D3418-8. If the maximum peak is less than 40 ° C., the self-cohesive force of the wax becomes weak, and as a result, the high-temperature offset resistance becomes weak, which is not preferable. On the other hand, the maximum peak is 1
If it exceeds 10 ° C., the fixing temperature increases, which is not preferable.
Further, when a toner is obtained by a direct polymerization method,
If the temperature of the maximum peak value is high due to granulation / polymerization in an aqueous system, a substance having a low softening point is deposited mainly during granulation, which is not preferable because the suspension system is hindered.

In the measurement of the temperature of the maximum peak value of the present invention,
For example, DSC-7 manufactured by Perkin Elemer Inc. is used. The temperature correction of the device detection unit uses the melting points of indium and zinc, and the heat quantity correction uses the heat of fusion of indium. An aluminum pan was used as a sample, an empty pan was set as a control, and the temperature was raised at a rate of 10 ° C./min. Was measured.

The wax used in the present invention includes ester wax, paraffin wax, polyolefin wax, Fischer-Tropsch wax,
Examples include amide waxes, higher fatty acids and their derivatives or graft / block compounds thereof, and ester waxes are particularly preferred.

When the low softening point substance is an ester wax having an ester compound, the wax exhibits good transparency, and when contained in toner particles, shows good fixability. After dissolving the low softening point substance and the polar resin in a polymerizable monomer, by promoting the polymerization reaction of the polymerizable monomer in an aqueous medium, the charge amount of the obtained toner particles is large, It is possible to obtain an excellent toner which has a high speed until reaching an appropriate charge value and has a small variation in the triboelectric charge amount in a multi-sheet durability.

As the polymerizable monomer used in the toner of the present invention, a vinyl polymerizable monomer capable of radical polymerization is used. As the vinyl polymerizable monomer, a monofunctional polymerizable monomer or a polyfunctional polymerizable monomer can be used.

As the monofunctional polymerizable monomer, styrene; α-methylstyrene, β-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, 2,4-dimethylstyrene, p-methylstyrene n-butylstyrene, p-tert-butylstyrene, p-n-hexylstyrene, p-n-octylstyrene, p-n-nonylstyrene, p-n-decylstyrene, p-n-dodecylstyrene, p-methoxy Styrene derivatives such as styrene and p-phenylstyrene; methyl acrylate, ethyl acrylate, n-propyl acrylate, iso-propyl acrylate, n-butyl acrylate, iso
-Butyl acrylate, tert-butyl acrylate, n-amyl acrylate, n-hexyl acrylate, 2-ethylhexyl acrylate, n-octyl acrylate, n-nonyl acrylate, cyclohexyl acrylate, benzyl acrylate, dimethyl phosphate ethyl acrylate, diethyl phosphate ethyl Acrylic polymerizable monomers such as acrylate, dibutyl phosphate ethyl acrylate and 2-benzoyloxyethyl acrylate; methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, iso-propyl methacrylate, n-butyl methacrylate, iso-butyl methacrylate; tert
-Butyl methacrylate, n-amyl methacrylate,
Methacrylic polymerizable monomers such as n-hexyl methacrylate, 2-ethylhexyl methacrylate, n-octyl methacrylate, n-nonyl methacrylate, diethyl phosphate ethyl methacrylate, dibutyl phosphate ethyl methacrylate; methylene aliphatic monocarboxylic acid esters; acetic acid Vinyl esters such as vinyl, vinyl propionate, vinyl butyrate, vinyl benzoate and vinyl formate; vinyl ethers such as vinyl methyl ether, vinyl ethyl ether and vinyl isobutyl ether; vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone and vinyl isopropyl ketone. No.

These can be used alone or in general in the published Polymer Handbook, 2nd edition III-P 139-192.
The monomers are appropriately mixed and used so that the theoretical glass transition temperature (Tg) described in (John Wiley & Sons) shows 40 to 75 ° C. Theoretical glass transition temperature is 4
If the temperature is lower than 0 ° C., problems arise in terms of the storage stability of the toner and the durability stability of the developer. On the other hand, if the temperature is higher than 75 ° C., the fixing point is increased. The color mixture of each color toner is insufficient and the color reproducibility is poor, and the transparency of the OHP image is remarkably reduced, which is not preferable from the viewpoint of high image quality. The molecular weight of the toner is GPC
(Gel permeation chromatography). As a specific GPC measurement method, the toner is extracted in advance with a toluene solvent using a Soxhlet extractor for 20 hours, and then the toluene is distilled off with a rotary evaporator. After washing sufficiently by adding an organic solvent that cannot be dissolved, such as chloroform, and the like, a solution dissolved in THF (tetrahydrofuran) was filtered through a solvent-resistant membrane filter having a pore diameter of 0.3 μm, and a sample manufactured by Waters Co., Ltd.
Using 50C, the column configuration was A-801 manufactured by Showa Denko,
802, 803, 804, 805, 806, 807 can be connected to measure the molecular weight distribution using a standard polystyrene resin calibration curve.

The measurement of the THF insoluble content of the toner of the present invention is as follows.
This is performed as follows.

1 g of the toner particles or the toner is precisely weighed, charged into a cylindrical filter paper, and subjected to Soxhlet extraction with 200 ml of THF for 20 hours. After that, remove the cylindrical filter paper.
It is calculated from the following formula by measuring the mass of the residue by vacuum drying for 0 hour. Note that the resin component of the toner is a component obtained by removing the magnetic powder, the charge control agent, the release agent component, the external additive, and the pigment from the toner. When the THF-insoluble component is measured, these components are converted to THF. The THF-insoluble content is calculated based on the resin component in consideration of whether it is soluble or insoluble. THF-insoluble matter (%) = (W2-W3) / (W1-W3-
W4) × 100 where W1 is the mass of the toner, W2 is the mass of the residue, W3 is the mass of a component insoluble in THF other than the resin component of the toner, W4
Represents the mass of a component soluble in THF other than the resin component of the toner.

The molecular weight distribution of the THF-soluble component of the toner of the present invention is such that the main peak molecular weight Mp is 5,000 to 5,
0000 and a weight average molecular weight Mw of 50,000 to 1
It is preferably 000000.

If the main peak molecular weight Mp is less than 5,000 or the weight average molecular weight Mw is less than 50,000, the durability is impaired, and conversely, the main peak molecular weight Mp exceeds 50,000, or the weight average molecular weight Mw is reduced. 1
If it exceeds 000000, the fixing property is inferior, which is not preferable.

As the polymerization initiator (the polymerization initiator added at the first time) used in the polymerization of the above-mentioned polymerizable monomer, an oil-soluble initiator is preferably used. For example, examples of the oil-soluble initiator include 2,2′-azobisisobutyronitrile, 2,2′-azobis-2,4-dimethylvaleronitrile, and 1,1′-azobis (cyclohexane-1-carbonitrile). , 2,2'-azobis-4-methoxy-
Azo compounds such as 2,4-dimethylvaleronitrile; acetylcyclohexylsulfonyl peroxide, diisopropyl peroxycarbonate, decanoyl peroxide, lauroyl peroxide, stearoyl peroxide, propionyl peroxide, acetyl peroxide, t-butylperoxy- 2-ethylhexanoate, benzoyl peroxide, t-butylperoxyisobutyrate, cyclohexanone peroxide, methyl ethyl ketone peroxide, dicumyl peroxide, t-butylhydroperoxide, di-t-butylperoxide, cumenehydro Peroxide initiators such as peroxides can be used.

The amount of the polymerization initiator added for the first time is preferably from 0.1 to 10 parts by mass based on 100 parts by mass of the polymerizable monomer.

In the present invention, in order to control the degree of polymerization of the polymerizable monomer, a chain transfer agent, a polymerization inhibitor and the like may be further added and used.

As the colorant used in the present invention, a black colorant that is toned to black using carbon black, a magnetic substance, and the following yellow / magenta / cyan colorants is used. In the case of a colorant used in a toner produced by a polymerization method, it is necessary to pay attention to the polymerization inhibitory property and the water phase migration property of the colorant. The colorant is preferably subjected to a surface modification (for example, a hydrophobic treatment that does not inhibit polymerization). In particular, dyes and carbon black need to be carefully used because many of them have polymerization inhibitory properties.

Examples of the yellow colorant include condensed azo compounds, isoindolinone compounds, anthraquinone compounds,
Compounds represented by azo metal complexes, methine compounds and allylamide compounds are used. Specifically, C.I. I. Pigment Yellow 12, 13, 14, 15, 17, 6
2, 74, 83, 93, 94, 95, 109, 110,
111, 128, 129, 147, 168, 180 and the like are preferably used.

As the magenta coloring agent, condensed azo compounds, diketopyrrolopyrrole compounds, anthraquinones, quinacridone compounds, basic dye lake compounds, naphthol compounds, benzimidazolone compounds, thioindigo compounds and perylene compounds are used. Specifically, C.I.
I. Pigment Red 2, 3, 5, 6, 7, 23, 4
8: 2, 48: 3, 48: 4, 57: 1, 81: 1, 1
22, 146, 166, 169, 177, 184, 18
5, 202, 206, 220, 221, 254 are particularly preferred.

As the cyan colorant used in the present invention, copper phthalocyanine compounds and derivatives thereof, anthraquinone compounds, basic dye lake compounds and the like can be used.
Specifically, C.I. I. Pigment Blue 1, 7, 15,
15: 1, 15: 2, 15: 3, 15: 4, 60, 6
2, 66 and the like are particularly preferably used.

These colorants can be used alone or as a mixture or in the form of a solid solution. The colorant of the present invention is selected from the viewpoints of hue angle, saturation, lightness, weather resistance, OHP transparency, and dispersibility in toner. The colorant is used in an amount of 1 to 20 parts by mass per 100 parts by mass of the resin.

Further, the toner of the present invention contains a magnetic material as a colorant and can be used as a magnetic toner. In this case, the magnetic material can also serve as a colorant. In the present invention, the magnetic material contained in the magnetic toner includes iron oxide such as magnetite, hematite, and ferrite; metals such as iron, cobalt, and nickel; and aluminum, cobalt, copper, lead, magnesium, and tin of these metals. , Zinc, antimony, beryllium, bismuth,
Cadmium, calcium, manganese, selenium, titanium,
Alloys of metals such as tungsten and vanadium and mixtures thereof can be given.

The magnetic material used in the present invention is more preferably a surface-modified magnetic material. When the magnetic material is used in a polymerization toner, it is hydrophobized by a surface modifier which is a substance having no polymerization inhibition. Those that have been treated are preferred. Examples of such a surface modifier include a silane coupling agent and a titanium coupling agent. These magnetic materials have an average particle size of 2 μm or less, preferably 0.1 μm or less.
Those having a thickness of about 1 to 0.5 μm are preferred. The amount to be contained in the toner particles is about 2 parts per 100 parts by mass of the binder resin.
The amount is preferably 0 to 200 parts by mass, particularly preferably 40 to 150 parts by mass with respect to 100 parts by mass of the binder resin.

The magnetic properties when 7.96 × 10 ² kA / m was applied were as follows: coercive force (Hc) 1.59 to 23.9 kA / m, saturation magnetization (σs) 50 to ²⁰⁰ Am ² / kg, remanent magnetization (σ
r) A magnetic material of ^{2 to 20} Am ² / kg is preferred.

The toner of the present invention may contain a charge control agent.

The following substances control the toner to be negatively charged.

For example, organic metal compounds and chelate compounds are effective, and examples thereof include monoazo metal compounds, acetylacetone metal compounds, aromatic hydroxycarboxylic acids, and aromatic dicarboxylic acid-based metal compounds. Other examples include aromatic hydroxycarboxylic acids, aromatic mono- and polycarboxylic acids and their metal salts, anhydrides, esters, and phenol derivatives such as bisphenol. Furthermore, urea derivatives, metal-containing salicylic acid-based compounds, metal-containing naphthoic acid-based compounds, boron compounds, quaternary ammonium salts, calixarenes and the like can be mentioned.

The following substances control the toner to be positively charged.

Nigrosine modified with nigrosine and fatty acid metal salts, guanidine compounds, imidazole compounds, quaternary ammonium salts such as tributylbenzylammonium-1-hydroxy-4-naphthosulfonate and tetrabutylammonium tetrafluoroborate;
And onium salts such as phosphonium salts, which are analogs thereof, and lake pigments thereof, triphenylmethane dyes, and these lake pigments (as the lake-forming agent, phosphotungstic acid, phosphomolybdic acid, phosphotungsten molybdic acid, tannic acid) , Lauric acid, gallic acid, ferricyanide, ferrocyanide, etc.), metal salts of higher fatty acids; diorganotin oxides such as dibutyltin oxide, dioctyltin oxide, dicyclohexyltin oxide; dibutyltin borate, dioctyltin borate, dicyclohexyltin borate And diorganotin borates. These can be used alone or in combination of two or more.

The charge control agent is preferably used in an amount of 0.01 to 20 parts by mass, more preferably 0.5 to 10 parts by mass, per 100 parts by mass of the binder resin.

From the viewpoint of durability, the additive for improving various properties of the toner preferably has a particle diameter of 1/5 or less of the volume average diameter of the toner particles. The particle size of the additive means the average particle size of the toner particles obtained by observing the surface of the toner particles with an electron microscope. As additives for imparting these properties, for example, the following are used.

Examples of the fluidity-imparting agent include metal oxides (such as silicon oxide, aluminum oxide, and titanium oxide), carbon black, and carbon fluoride. Those subjected to a hydrophobic treatment are more preferable.

Examples of the abrasive include metal oxides (such as strontium titanate, cerium oxide, aluminum oxide, magnesium oxide and chromium oxide), nitrides (such as silicon nitride), carbides (such as silicon carbide), and metal salts (calcium sulfate). , Barium sulfate, calcium carbonate, etc.).

Examples of the lubricant include fluororesin powder (vinylidene fluoride, polytetrafluoroethylene, etc.) and fatty acid metal salts (zinc stearate, calcium stearate, etc.).

Examples of the charge control particles include metal oxides (such as tin oxide, titanium oxide, zinc oxide, silicon oxide, and aluminum oxide) and carbon black.

These additives are used in an amount of 0.1 to 10 parts by mass, preferably 0.1 to 5 parts by mass, based on 100 parts by mass of the toner particles. These additives may be used alone or in combination of two or more.

As a method for producing toner particles, a low softening point substance such as a wax, a coloring agent, a crosslinking agent, and other additives are added to a polymerizable monomer, and the mixture is uniformly dissolved with a homogenizer, an ultrasonic disperser, or the like. Or, the polymerizable monomer composition dispersed, in an aqueous medium containing a dispersion stabilizer, a conventional stirrer, a homomixer, a stirrer collectively referred to as a homogenizer, for example, as such a high-speed rotary shear stirrer Is T. K homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.), CLEARMIX (manufactured by M Technique Co., Ltd.), Polytron homogenizer (KINEMATICA), Supraton (manufactured by Tsukishima Kikai Co., Ltd.), etc. The granulation is performed by adjusting the stirring speed and time so that the droplets of the body composition have the desired size of the toner particles. During or after the granulation step, a polymerization initiator is added. Polymerization initiator added at this time (initial polymerization initiator)
May be previously added to the polymerizable monomer composition. Thereafter, stirring may be performed to such an extent that the state of the particles is maintained and the sedimentation of the particles is prevented by the action of the dispersion stabilizer. Polymerization temperature is 40 ° C or higher, usually 50 to 90 ° C
(Preferably 55 to 85 ° C.) and the polymerization is carried out.

When the conversion of the polymerizable monomer reaches 70 to 99%, the second or subsequent polymerization initiator is added by the method of the present invention, and the reaction temperature is raised by 5 ° C. or more. More preferably, the temperature is raised by 10 ° C. or more. This heating may be performed before the addition of the polymerization initiator. Further, in order to remove unreacted polymerizable monomers and by-products which cause odor at the time of fixing the toner, the aqueous medium may be partially distilled off in the latter half of the reaction or after completion of the reaction. After the reaction, the generated toner particles are collected by washing and filtration, and dried.

In the suspension polymerization method, it is usually preferable to use 300 to 3000 parts by weight of water as a dispersion medium with respect to 100 parts by weight of the monomer composition. Examples of the dispersant used include inorganic oxides such as tricalcium phosphate, magnesium phosphate, aluminum phosphate, zinc phosphate, calcium carbonate, magnesium carbonate, calcium hydroxide,
Examples include magnesium hydroxide, aluminum hydroxide, calcium metasilicate, calcium sulfate, barium sulfate, bentonite, silica, and alumina. As the organic compound, for example, polyvinyl alcohol, gelatin, methylcellulose, methylhydroxypropylcellulose, ethylcellulose, sodium salt of carboxymethylcellulose, starch and the like are used. These dispersants are
It is preferable to use 0.2 to 2.0 parts by mass based on 100 parts by mass of the polymerizable monomer.

As these dispersants, commercially available ones may be used as they are. However, in order to obtain finely dispersed particles having a uniform particle size, the inorganic compound may be formed under high-speed stirring in a dispersion medium. I can do it. For example, in the case of tricalcium phosphate, a dispersant suitable for a suspension polymerization method can be obtained by mixing an aqueous solution of sodium phosphate and an aqueous solution of calcium chloride under high-speed stirring. A surfactant of 0.001 to 0.1% by mass may be used in combination for miniaturization of these dispersants. Specifically, commercially available nonionic, anionic and cationic surfactants can be used. For example, sodium dodecyl sulfate, sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate,
Sodium oleate, sodium laurate, potassium stearate, calcium oleate and the like are preferably used.

When used as a two-component developer, a carrier is used as a developer together with the toner of the present invention. The magnetic carrier is composed of an element consisting of iron, copper, zinc, nickel, cobalt, manganese, and chromium alone or in a composite ferrite state. The shape of the magnetic carrier is spherical, flat, or irregular. Furthermore, the fine structure of the surface state of the magnetic carrier particles (for example, surface unevenness)
Is also preferably controlled. In general, a method is used in which magnetic carrier core particles are generated in advance by baking and granulating the inorganic oxide, and then coating the resin with a resin. From the standpoint of reducing the load on the toner of the magnetic carrier, after kneading the inorganic oxide and the resin, pulverizing and classifying to obtain a low-density dispersion carrier, or further, directly kneading the inorganic oxide and the monomer It is also possible to use a method of obtaining a spherical magnetic carrier by suspension polymerization in an aqueous medium.

A coated carrier for coating the surface of the carrier particles with a resin is particularly preferred. As the method, a method of dissolving or suspending the resin in a solvent, applying the resin, and attaching the resin to the carrier, or a method of simply mixing the resin powder and the carrier particles and attaching the mixture is applicable.

The substance fixed to the surface of the carrier particles varies depending on the toner material. Examples thereof include polytetrafluoroethylene, monochlorotrifluoroethylene polymer, polyvinylidene fluoride, silicone resin, polyester resin, styrene resin, acrylic resin, and polyamide resin. , Polyvinyl butyral, amino acrylate resin and the like. These may be used alone or in combination.

The magnetic properties of the carrier are preferably as follows.
Magnetic field strength after magnetic saturation of 79.6 kA / m
The magnetization intensity (σ79.6) at 3.77 to 3
It is required to be 7.7 μWb / cm ³ . In order to achieve higher image quality, preferably 12.6 to 3
Preferably, it is 1.4 Wb / cm ³ . 37.7 μWb
If it is larger than / cm ^3, it becomes difficult to obtain a high quality toner image. When it is less than 3.77 Wb / cm ³ ,
Since the magnetic binding force is also reduced, carrier adhesion is likely to occur.

When a two-component developer is prepared by mixing the toner of the present invention and a magnetic carrier, the mixing ratio is 2 to 15% by mass, preferably 4% by mass, as the toner concentration in the developer.
Good results are usually obtained when the content is set to 通常 13% by mass.

An image forming method to which the toner of the present invention can be applied will be described below with reference to the accompanying drawings.

The toner of the present invention can be mixed with a magnetic carrier and applied to an image forming method using, for example, developing means 37 as shown in FIG. Specifically, while applying an alternating electric field, the magnetic brush is used to hold the electrostatic image holder (for example,
It is preferable that the development is performed in a state of being in contact with the photosensitive drum 33. The distance (S-D distance) B between the developer carrier (developing sleeve) 31 and the photosensitive drum 33 is 100 to 1
000 μm is good in preventing carrier adhesion and improving dot reproducibility. If it is smaller than 100 μm, the supply of the developer tends to be insufficient and the image density is reduced. If it is larger than 1000 μm, the magnetic field lines from the magnet S1 are widened and the density of the magnetic brush is reduced, resulting in poor dot reproducibility or restrained carrier. And the carrier is likely to adhere. The toner 41 is sequentially supplied to the developing device,
The toner is mixed with the carrier by the stirring means 35 and 36 and transported to the developing sleeve 42 containing the fixed magnet 34.

The voltage between the peaks of the alternating electric field is 500 to 50.
00V is preferable, the frequency is 500 to 10000 Hz,
The frequency is preferably 500 to 3000 Hz, and can be appropriately selected and used for each process. In this case, the waveform may be triangular, rectangular, sine, or Duty.
Various selections such as waveforms with different ratios can be used. If the applied voltage is lower than 500 V, it is difficult to obtain a sufficient image density, and it may not be possible to satisfactorily collect fog toner in the non-image area. If the voltage exceeds 5000 V, the electrostatic image may be disturbed via the magnetic brush, which may cause deterioration in image quality.

By using a two-component developer having a well-charged toner, the fog removal voltage (Vback)
And the primary charge of the photoconductor can be reduced, so that the life of the photoconductor can be extended. Vbac
k is preferably 150 V or less, more preferably 100 V or less, depending on the developing system.

As the contrast potential, 200 to 500 V is preferably used so that a sufficient image density can be obtained.

When the frequency is lower than 500 Hz, although it depends on the process speed, the charge may be injected into the carrier, so that the image quality may be deteriorated due to the adhesion of the carrier or the disturbance of the latent image. If the frequency exceeds 10,000 Hz, the toner cannot follow the electric field, and the image quality is likely to deteriorate.

In order to obtain a sufficient image density, achieve excellent dot reproducibility, and perform development without carrier adhesion, the contact width (developing nip C) of the magnetic brush on the developing sleeve 31 with the photosensitive drum 33 is preferably set. 3 to 8 mm. If the developing nip C is narrower than 3 mm, it is difficult to sufficiently satisfy a sufficient image density and dot reproducibility.
If it is wider than mm, packing of the developer occurs to stop the operation of the machine, and it is difficult to sufficiently suppress the adhesion of the carrier. As a method of adjusting the developing nip, the nip width is appropriately adjusted by adjusting the distance A between the developer regulating member 32 and the developing sleeve 31 or adjusting the distance B between the developing sleeve 31 and the photosensitive drum 33.

In the output of a full-color image particularly in which halftone is emphasized, three or more developing units for magenta, cyan and yellow are used, and a digital latent image is formed using the toner of the present invention. By combining with a developing system, there is no influence of the magnetic brush, and it is possible to faithfully develop the dot latent image without disturbing the latent image. In the transfer step, a high transfer rate can be achieved by using the toner of the present invention, so that high image quality can be achieved in both the halftone portion and the solid portion.

Furthermore, by using the toner of the present invention together with the initial improvement of the image quality, the effect of the present invention without deterioration in image quality can be sufficiently exerted even when copying a large number of sheets.

The toner image on the electrostatic image holder 33 is transferred to a transfer material by a transfer means 43 such as a corona charger.
The toner image on the transfer material is fixed by a heat and pressure fixing unit having a heating roller 46 and a pressure roller 45, and a fixed image is formed on the transfer material. Electrostatic image holder 33
The upper transfer residual toner is removed from the electrostatic image holder 33 by cleaning means 44 such as a cleaning blade.
The toner of the present invention has a high transfer efficiency in the transfer step, a small amount of untransferred toner, and an excellent cleaning property, so that filming hardly occurs on the electrostatic image holding member. Further, even when a multi-sheet durability test is performed, the toner of the present invention has less embedding of the external additive on the surface of the toner particles than the conventional toner, so that good image quality can be maintained for a long time.

In order to obtain a good full-color image, it is preferable that a developing device for magenta, cyan, yellow, and black is provided, and a tight image is obtained by performing black development last. it can.

An example of an image forming apparatus capable of favorably performing a multi-color or full-color image forming method will be described with reference to FIG.

The color electrophotographic apparatus shown in FIG. 4 includes a transfer material transport system I provided from the right side of the apparatus main body to substantially the center of the apparatus main body, and the transfer material transport system I provided substantially at the center of the apparatus main body. And a developing unit (that is, a rotary developing device) III disposed in close proximity to the latent image forming unit II. It is roughly divided.

The transfer material transport system I has the following configuration. An opening is formed in a right wall (right side in FIG. 4) of the apparatus main body, and detachable transfer material supply trays 302 and 303 are provided in the opening so as to partially protrude outside the apparatus. Feed rollers 304 and 315 are disposed almost directly above the trays 302 and 303, and link the feed rollers 304 and 305 with a transfer drum 315 disposed to the left and rotatable in the direction of the arrow. Thus, the paper feed roller 306 and the paper feed guides 307 and 308 are provided. In the vicinity of the outer peripheral surface of the transfer drum 315, the contact roller 30 is moved from the upstream side to the upstream side in the rotation direction.
9, a gripper 310, a transfer material separating charger 311, and a separating claw 312 are sequentially arranged.

A transfer charger 313 and a transfer material separating charger 314 are disposed on the inner peripheral side of the transfer drum 315. A transfer sheet (not shown) made of a polymer, such as polyvinylidene fluoride, is attached to a portion of the transfer drum 315 around which the transfer material is wound, and the transfer material is electrostatically placed on the transfer sheet. It is stuck on. At the upper right side of the transfer drum 315, a conveyor belt unit 316 is disposed in close proximity to the separation claw 312. At the end (right side) of the conveyor belt unit 316 in the transfer material transport direction (right side), a fixing device 318 is disposed. I have. A discharge tray 317 that extends outside the apparatus main body 301 and that is detachable from the apparatus main body 301 is provided downstream of the fixing device 318 in the transport direction.

Next, the configuration of the latent image forming section II will be described. A photosensitive drum (for example, an OPC photosensitive drum) 319, which is a latent image carrier rotatable in the direction of the arrow in FIG. 4, is provided with its outer peripheral surface in contact with the outer peripheral surface of the transfer drum 315. Above the photosensitive drum 319 and in the vicinity of the outer peripheral surface thereof, from the upstream side to the downstream side in the rotation direction of the photosensitive drum 319, a charge removing charger 321 and a cleaning unit 320 are arranged.
And a primary charger 323 are sequentially arranged. Further, an image exposure unit 324 such as a laser beam scanner for forming an electrostatic latent image on the outer peripheral surface of the photosensitive drum 319 and an image exposure reflection unit 325 such as a mirror are provided. It is arranged.

The configuration of the rotary developing device III is as follows. A rotatable housing (hereinafter referred to as a “rotating body”) 3 is provided at a position facing the outer peripheral surface of the photosensitive drum 319.
26, and four types of developing devices are mounted in the rotating body 326 at four positions in the circumferential direction.
9, the electrostatic latent image formed on the outer peripheral surface is visualized (that is, developed). The four types of developing devices include a yellow developing device 327Y, a magenta developing device 327M, a cyan developing device 327C, and a black developing device 327BK, respectively.

The sequence of the entire image forming apparatus having the above configuration will be described by taking a full color mode as an example. When the above-described photosensitive drum 319 rotates in the direction of the arrow in FIG.
Charged by 4, the peripheral speed of the photosensitive drum 319 (hereinafter referred to as process speed) is 1
00 mm / sec or more (for example, 130 to 250 mm /
sec). When the photosensitive drum 319 is charged by the primary charger 323, image exposure is performed by the laser light E modulated by the yellow image signal of the document 328, and an electrostatic latent image is formed on the photosensitive drum 319,
By the rotation of the rotating body 326, the electrostatic latent image is developed by the yellow developing device 327Y fixed at the developing position in advance, and a yellow toner image is formed.

A paper feed guide 307, a paper feed roller 306,
The transfer material transported via the paper feed guide 308 is
It is held by the gripper 310 at a predetermined timing,
The transfer roller 315 is electrostatically wound around the contact roller 309 and an electrode facing the contact roller 309. The transfer drum 315 includes a photosensitive drum 319.
4, the yellow toner image formed by the yellow developing device 327Y is
The outer peripheral surface of the photosensitive drum 319 and the transfer drum 315
Is transferred onto a transfer material by a transfer charger 313 at a portion where the outer peripheral surface of the transfer member contacts. The transfer drum 315 continues to rotate as it is, and the next color (magenta in FIG. 4)
Prepare for transcription.

The photosensitive drum 319 is provided with
After being removed by the cleaning device 21 and cleaned by the cleaning means 320 using a cleaning blade, the primary charging device 323 again charges the image, performs image exposure using the next magenta image signal, and forms an electrostatic latent image. The rotary developing device rotates while an electrostatic latent image is formed on the photosensitive drum 319 by image exposure based on a magenta image signal, and causes the magenta developing device 327M to be disposed at the above-described predetermined developing position. Develop with magenta toner. Subsequently, the above-described process is also performed for cyan and black, respectively. When the transfer of the four-color toner image is completed, the three-color visual image formed on the transfer material is transferred to each of the chargers 322 and 314. , The gripping of the transfer material by the gripper 310 is released, and the transfer material is separated from the transfer drum 315 by the separation claw 312.
18 and is fixed by heat and pressure to complete a series of full-color print sequences, and a required full-color print image is formed on one surface of the transfer material.

Next, another image forming method will be described with reference to FIG.

In the apparatus system shown in FIG. 5, the developing units 74-1, 74-2, 74-3, and 74-4 respectively include a developer having a cyan toner, a developer having a magenta toner, and a developing device having a yellow toner. A developer having a developer and a black toner is introduced, and the electrostatic charge image formed on the photoconductor 71 is developed by a magnetic brush development system or a non-magnetic one-component development system, so that a toner image of each color is formed on the photoconductor 71. . The photoconductor 71 is made of a-Se, Cds, ZnO ₂ ,
A photosensitive drum or a photosensitive belt having a photoconductive insulating material layer such as OPC or a-Si. The photoconductor 71 is rotated in a direction indicated by an arrow by a driving device (not shown).

As the photosensitive member 71, a photosensitive member having an amorphous silicon photosensitive layer or an organic photosensitive layer is preferably used.

As the organic photosensitive layer, the photosensitive layer contains a charge generating substance and a substance having charge transport performance in the same layer.
It may be a single-layer type or a function-separated type photosensitive layer having a charge transport layer as a component of the charge transport layer. A laminated photosensitive layer having a structure in which a charge generation layer and then a charge transport layer are laminated on a conductive substrate in this order is one of preferred examples.

The binder resin for the organic photosensitive layer is preferably a polycarbonate resin, a polyester resin, or an acrylic resin, particularly having good transferability and cleaning properties, and has poor cleaning, fusion of toner to a photoreceptor, and filming of external additives. Less likely.

In the charging step, there are a system that is not in contact with the photoreceptor 71 using a corona charger and a contact system that uses a roller or the like, and any of them is used. Fig. 5 for efficient uniform charging, simplification, and low ozone generation
As shown in the above, a contact type is preferably used.

The charging roller 72 basically has a central core bar 72b and a conductive elastic layer 72a formed on the outer periphery thereof. The charging roller 72 is pressed against the surface of the photoconductor 71 with a pressing force, and is driven to rotate as the photoconductor 71 rotates.

As a preferable process condition when the charging roller is used, the contact pressure of the roller is 4.9 to 490 N.
/ M (0.5 to 50 kg / m), when an AC voltage superimposed on a DC voltage is used, the AC voltage is 0.5 to 5
kVpp, AC frequency = 50 Hz to 5 kHz, DC voltage = ± 0.2 to ± 1.5 kV, and when DC voltage is used, DC voltage = ± 0.2 to ± 5 kV.

Other charging methods include a method using a charging blade and a method using a conductive brush. These contact charging means are effective in that high voltage is not required and generation of ozone is reduced.

The material of the charging roller and the charging blade as the contact charging means is preferably conductive rubber, and a release coating may be provided on the surface thereof. As the release coating, a nylon resin, PVDF (polyvinylidene fluoride), PVDC (polyvinylidene chloride) or the like can be applied.

The toner image on the photosensitive member is applied with a voltage (for example, ±
(0.1 to ± 5 kV). The surface of the photoreceptor after the transfer is cleaned by cleaning means 79 having a cleaning blade 78.

The intermediate transfer member 75 comprises a pipe-shaped conductive core 75b and a medium-resistance elastic layer 75 formed on the outer peripheral surface thereof.
a. The core metal 75b may be formed by applying a conductive plating to a plastic pipe.

The medium resistance elastic layer 75a is made of silicone rubber, fluorine rubber, chloroprene rubber, urethane rubber,
EPDM (terpolymer of ethylene propylene diene)
A conductive material such as carbon black, zinc oxide, tin oxide, and silicon carbide is mixed and dispersed in an elastic material such as the above to adjust the electric resistance (volume resistivity) to a medium resistance of 10 ⁵ to 10 ¹¹ Ω · cm. It is a solid or foamed layer.

The intermediate transfer member 75 is provided in parallel with the photosensitive member 71 so as to be in contact with the lower surface of the photosensitive member 71, and is arranged in the counterclockwise direction indicated by an arrow at the same peripheral speed as the photosensitive member 71. Rotate.

In the process in which the first color toner image formed and carried on the surface of the photosensitive member 71 passes through the transfer nip where the photosensitive member 71 and the intermediate transfer member 75 are in contact, the transfer bias applied to the intermediate transfer member 75 The intermediate transfer is sequentially performed on the outer surface of the intermediate transfer body 75 by the electric field formed in the transfer nip area.

If necessary, the surface of the intermediate transfer member 75 is cleaned by the detachable cleaning means 80 after the transfer of the toner image onto the transfer material. When there is a toner image on the intermediate transfer member, the cleaning unit 80 is separated from the surface of the intermediate transfer member so as not to disturb the toner image.

A transfer means is provided in parallel with the intermediate transfer body 75 and is brought into contact with the lower surface of the intermediate transfer body 75. The transfer means 77 is, for example, a transfer roller or a transfer belt. It rotates clockwise with the same peripheral speed as the arrow. The transfer unit 77 may be disposed so as to directly contact the intermediate transfer body 75, or a belt or the like may be disposed so as to contact between the intermediate transfer body 75 and the transfer unit 77.

In the case of the transfer roller, the transfer roller is basically composed of a central core 77b and a conductive elastic layer 77a formed on the outer periphery thereof.

For the intermediate transfer member and the transfer roller, general materials can be used. By setting the volume resistivity of the elastic layer of the transfer roller smaller than the volume resistivity of the elastic layer of the intermediate transfer body, the voltage applied to the transfer roller can be reduced, and a good toner image can be formed on the transfer material. It is possible to form the transfer material and to prevent the transfer material from winding around the intermediate transfer member. In particular, it is particularly preferable that the volume resistivity of the elastic layer of the intermediate transfer member is at least 10 times the volume resistivity of the elastic layer of the transfer roller.

The hardness of the intermediate transfer member and the transfer roller is J
It is measured according to ISK-6301. The intermediate transfer member used in the present invention is preferably composed of an elastic layer belonging to the range of 10 to 40 degrees. On the other hand, the hardness of the elastic layer of the transfer roller is higher than the hardness of the elastic layer of the intermediate transfer member.
Those having a value of 1 to 80 degrees are preferable from the viewpoint of preventing the transfer material from being wound around the intermediate transfer member. When the hardness of the intermediate transfer body and that of the transfer roller are reversed, a concave portion is formed on the transfer roller side, and the winding of the transfer material around the intermediate transfer body is likely to occur.

The transfer means 77 rotates the intermediate transfer member 75 at a constant speed or at a different peripheral speed. The transfer material 76 is conveyed between the intermediate transfer body 75 and the transfer means 77,
The toner image on the intermediate transfer body 75 is transferred to the surface of the transfer material 76 by applying a bias having a polarity opposite to the frictional charge of the toner to the transfer unit 77 from the transfer bias unit.

As the material of the transfer rotary member, the same material as that of the charging roller can be used. Preferred transfer process conditions include a contact pressure of the roller of 4.9 to 49.
At 0 N / m, the DC voltage is ± 0.2 to ± 10 kV.

For example, the conductive elastic layer 77 of the transfer roller
b is a polyurethane in which a conductive material such as carbon is dispersed,
Ethylene-propylene-diene terpolymer (EPD
M) or the like, and is made of an elastic body having a volume resistance of about 10 ⁶ to 10 ¹⁰ Ωcm. A bias is applied to the core 77a from a constant voltage power supply. The bias condition is ± 0.
2 to ± 10 kV is preferred.

Next, the transfer material 76 is conveyed to a fixing device 81 having a heating roller having a built-in heating element such as a halogen heater and an elastic pressure roller pressed against the heating roller with a pressing force. The toner image is heated and pressed and fixed on the transfer material by passing between the roller and the pressure roller. A fixing method using a heater via a film may be used.

Next, the one-component developing method will be described. The toner of the present invention can be applied to a one-component developing method such as a magnetic one-component developing method and a non-magnetic one-component developing method. The magnetic one-component developing method will be described with reference to FIG.

In FIG. 6, the substantially right half peripheral surface of the developing sleeve 83 is always in contact with the toner reservoir in the toner container 84, and the toner T near the surface of the developing sleeve 83 is brought into contact with the developing sleeve surface by the magnetic generating means in the sleeve. With a magnetic force of 85 and /
Or, it is attached and held by electrostatic force. Developing sleeve 83
There the magnetic toner layer when driven rotating the sleeve surface is formed as a thin magnetic toner T ₁ of the respective portions substantially uniform thickness in the process of passing through the position of the regulating member 86. The magnetic toner is charged mainly by frictional contact with the sleeve surface as the developing sleeve 83 rotates, and the magnetic toner thin layer surface on the developing sleeve 83 rotates toward the latent image holding member 87 as the developing sleeve 83 rotates. Then, the developer passes through the developing area A, which is the closest part between the latent image holding member 87 and the developing sleeve 83. During this passage process, the magnetic toner of the magnetic toner thin layer on the side of the developing sleeve 83 flies by the DC and AC electric fields applied between the latent image holding member 87 and the developing sleeve 83 by the bias applying means 96 due to the DC and AC voltages. It reciprocates between (the gap α) between the surface of the latent image holding member 87 in the area A and the surface of the developing sleeve 83. Finally the toner image T ₂ are sequentially formed by selectively transition adhere according to the potential pattern of the latent image on the surface of the magnetic toner a latent image holding member 87 side of the developing sleeve 83 side.

The surface of the developing sleeve, through which the magnetic toner has been selectively consumed after passing through the developing area A, is re-rotated into the toner reservoir of the toner container 84 to receive the supply of the magnetic toner again. magnetic thin toner layer T ₁ side of the developing sleeve 83 is transported, repeatedly developing process is performed.

The regulating member 86 as the toner thinning means used in FIG. 6 is a doctor blade such as a metal blade or a magnetic blade disposed at a predetermined gap from the sleeve. Alternatively, a metal, resin, or ceramic roller may be used instead of the doctor blade.

Further, an elastic blade (for example, 80 in FIG. 7) or an elastic roller which comes into contact with the surface of the developing sleeve (toner carrier) by an elastic force may be used as the toner thinning regulating member.

As the material for forming the elastic blade or the elastic roller, silicone rubber, urethane rubber, NBR
Rubber elastic body such as polyethylene terephthalate; and metal elastic body such as stainless steel, steel and phosphor bronze. A composite of them may be used.
Preferably, the sleeve contact portion is a rubber elastic body or a resin elastic body.

FIG. 7 shows an example in which an elastic blade is used.

The base on the upper side of the elastic blade 80 is fixed and held on the developer container side, and the lower side is on the elastic blade 8 side.
The inner surface of the elastic blade 80 (in the case of the reverse direction, the outer surface) is pressed against the surface of the developing sleeve 89 with an appropriate elasticity by bending the developing sleeve 89 in the forward or reverse direction against the elasticity of 0. To make contact. According to such an apparatus, a thin and dense toner layer can be obtained more stably with respect to environmental fluctuations.

When an elastic blade is used, a sleeve,
Although the toner easily fuses to the blade surface, the toner of the present invention is preferably used because of excellent releasability and stable triboelectric charging.

In the case of the magnetic one-component developing method, the blade 80
The contact pressure between the sleeve 89 and the sleeve 89 is 98 N / m or more, preferably 2.9 × 10 ² , as the linear pressure in the sleeve generatrix direction.
２．５2.5 × 10 ⁴ N / m, more preferably 4.9 × 10 ²
１．２1.2 × ⁴ N / m is preferred.

The gap α between the latent image holder 88 and the developing sleeve 89 is set to, for example, 50 to 500 μm. The thickness of the magnetic toner layer on the developing sleeve 89 is
Is most preferably smaller than the gap α between the magnetic toner layer and the developing sleeve 89, but in some cases, among the many ears of the magnetic toner constituting the magnetic toner layer, a part of the magnetic toner layer The layer thickness may be regulated.

The developing sleeve 89 is rotated at a peripheral speed of 100 to 200% with respect to the latent image holding member 88. The alternating bias voltage by the bias applying means 96 is 0.1 kV or more at peak to peak, preferably 0.2 to 3.0 kV,
More preferably, it is used at 0.3 to 2.0 kV.
The alternating bias frequency is 0.5 to 5.0 kHz, preferably 1/0 to 3.0 kHz, more preferably 1.5 to 5.0 kHz.
Used at 3.0 kHz. As the alternating bias waveform, a waveform such as a rectangular wave, a sine wave, a sawtooth wave, and a triangular wave can be applied. Also, asymmetrical AC biases having different positive and reverse voltages and times can be used. It is also preferable to superimpose a DC bias.

Next, an example of a developing method for performing non-magnetic one-component development will be described with reference to FIG. Reference numeral 75 denotes a latent image holding member, and a latent image is formed by an electrophotographic process unit or an electrostatic recording unit (not shown). A developing sleeve 74 is made of a non-magnetic sleeve such as aluminum or stainless steel.

As the developing sleeve 74, a rough tube of aluminum or stainless steel may be used as it is, but preferably the surface is uniformly roughened by spraying spherical particles such as glass beads, mirror-finished, or resin. What is coated with is good.

As the developing sleeve 74, a rough tube of aluminum or stainless steel may be used as it is, but preferably the surface is uniformly roughened by spraying spherical particles such as glass beads, mirror-finished, or resin. What is coated with is good.

The toner T is stored in a hopper 71 and is supplied onto a developing sleeve (toner carrier) 74 by a toner application roller 72. As the toner application roller 72, a roller made of a foamed material of a porous elastic body (for example, a soft polyurethane foam or the like) is preferably used. The roller is rotated with respect to the developing sleeve 74 in a forward or reverse direction at a non-zero relative speed, so that toner is supplied onto the developing sleeve 74 and the developing sleeve 74 is rotated.
The above-mentioned developed toner (undeveloped toner) is also stripped off. At this time, the developing sleeve 7 of the toner applying roller 72 is
In consideration of the balance between toner supply and stripping, the abutment width (nip width) of the sheet 4 is preferably 2.0 to 10.0 mm, more preferably 4.0 to 6.0 mm. Stress is applied to the toner to increase aggregation due to deterioration of the toner, or the developing sleeve 74 and the toner application roller 7
However, the toner of the present invention is excellent in fluidity and releasability, and has durability stability. Therefore, the toner of the present invention is preferably used also in the developing device shown in FIG. Instead of the toner application roller 72, a brush roller made of a resin fiber such as nylon or rayon may be used. The developing method shown in FIG. 8 is extremely effective in a one-component developing method using a non-magnetic one-component toner.

The toner supplied onto the developing sleeve 74 is thinly and uniformly applied by the regulating member 73. It is particularly preferable that the toner regulating member 73 presses the toner onto the surface of the developing sleeve 74 with an elastic blade or an elastic roller. The elastic blade or the elastic roller is preferably made of a material of a triboelectric series suitable for charging the toner to a desired polarity. The regulating member 73 is preferably made of silicone rubber, urethane rubber, styrene-butadiene rubber, or the like. Furthermore, even if an organic resin layer such as polyamide, polyimide, nylon, melamine, melamine crosslinked nimelon, phenol resin, fluorine resin, silicone resin, polyester resin, urethane resin, styrene resin, and acrylic resin is provided on the regulating member 73. good.

The contact pressure between the elastic blade or the elastic roller and the developing sleeve 74 is 0.98 to 245 N / m, preferably 4.9 to 11 as a linear pressure in the sleeve genera direction.
8N / m is effective and the contact pressure is 0.98-245N
By adjusting to / m, it is possible to effectively loosen the aggregation of the toner, and it is possible to instantaneously raise the triboelectric charge amount of the toner.

In a system in which a thin layer of toner is coated on the developing sleeve 74 with a blade, particularly in the non-magnetic one-component developing method, the developing sleeve 74 is attached to the latent image holding member 75 in order to obtain a sufficient image density. , 100-300
It is rotated at a peripheral speed of%. Preferably, it is rotated at a peripheral speed of 120 to 250%.

It is preferable that the thickness of the toner layer on the developing sleeve 74 is smaller than the length of the gap between the developing sleeve 74 and the latent image holding member 75, and an alternating electric field is formed in this gap. By applying a developing bias in which an alternating electric field or a DC electric field is superimposed on the alternating electric field to the developing sleeve 74 by the bias power supply 56, the movement of the toner from the developing sleeve 74 to the latent image holding member 75 is facilitated, and further high quality is achieved. Images can be obtained.

In the present invention, the conversion of the polymerizable monomer is as follows:
The amount of the polymerizable monomer in the reaction solution was quantified by gas chromatography and calculated.

In the present invention, the circularity of the toner is used as a simple method for quantitatively expressing the shape of the toner particles. In the present invention, the flow type particle image measuring device FPI is used.
The measurement was performed using Model A-1000 (manufactured by Toa Medical Electronics Co., Ltd.) and calculated using the following equation.

[0154]

(Equation 1)

Here, the “particle projection area” is the area of the binarized toner particle image, and “the perimeter of the particle projection image”.
Is defined as the length of the contour obtained by connecting the edge points of the toner particle image.

The circularity in the present invention is an index indicating the degree of unevenness of the toner particles. The circularity is 1.00 when the toner particles are completely spherical, and the circularity decreases as the surface shape becomes more complicated. Become.

The measurement of the particle size distribution of the toner is as follows.

A Coulter Counter TA-II or Coulter Multisizer II (manufactured by Coulter Inc.) is used as a measuring device. As the electrolyte, about 1% NaCl aqueous solution is prepared using primary sodium chloride. For example, I
SOTON-II (manufactured by Coulter Scientific Japan) can be used. As a measuring method, a surfactant (preferably an alkylbenzene sulfonate) is used as a dispersant in 100 to 150 ml of the electrolytic aqueous solution,
0.1-5 ml is added, and the measurement sample is further 2-20 mg.
Add. The electrolyte in which the sample is suspended is mixed with an ultrasonic
Performing a dispersion process for about 3 minutes, and measuring the volume and the number of toner particles for each channel by using the measuring device with a 100 μm aperture as an aperture.
The volume distribution and the number distribution of the toner are calculated. then,
The weight average particle size (D4) of the toner based on the weight obtained from the volume distribution of the toner particles (the median value of each channel is set as a representative value for each channel) is obtained.

The channels are 2.00 to 2.52
μm; 2.52 to 3.17 μm; 3.17 to 4.00 μm
m; 4.00 to 5.04 μm; 5.04 to 6.35 μm
m; 6.35 to 8.00 μm; 8.00 to 10.08 μm
m; 10.08 to 12.70 μm; 12.70 to 16.
00 μm; 16.00-20.20 μm; 20.20
25.40 μm; 25.40-32.00 μm;
13 channels of 00 to 40.30 μm are used.

Coefficient of variation A in the number distribution of toner particles
Is calculated from the following equation.

Coefficient of variation A = [S / D1] × 100 where S represents a standard deviation value in the number distribution of toner particles, and D1 is the number average particle diameter (μm) of the toner particles.
Is shown. ]

Various physical properties of toner and development, fixing and image quality evaluation methods in Examples described later will be described below.

(1) Measurement of charge amount of toner in each environment The charge amount of the environment is measured by the following method after the toner and the carrier are allowed to stand all day and night under each environmental condition.

For example, room temperature and normal humidity (23 ° C./60% R
H), the triboelectric charge of the toner is measured based on the blow-off method in an environment of high temperature / high humidity (30 ° C./80% RH) and low temperature / low humidity (15 ° C./10% RH).

FIG. 1 is an explanatory view of an apparatus for measuring a triboelectric charge amount of a toner. First, a mixture of a toner and a carrier having a mass ratio of 1:19 to be measured for a triboelectric charge amount is placed in a polyethylene bottle having a capacity of 50 to 100 ml in a metal measuring container 2 having a screen 3 having an opening of 25 μm at the bottom. The mixture is shaken by hand for 5 to 10 minutes, and about 0.5 to 1.5 g of the mixture (developer) is put in and the metal lid 4 is closed. At this time, the mass of the entire measurement container 2 is weighed and defined as W ₁ (g). Next, in the suction device 1 (at least the portion in contact with the measurement container 2 is at least an insulator), the air is sucked from the suction port 7 and the air volume control valve 6 is adjusted to adjust the pressure of the vacuum gauge 5 to 2.5 × 10 ³ Pa. In this state, suction is sufficiently performed, preferably for 2 minutes, to remove the toner by suction. The potential of the electrometer 9 at this time is V (volt).
And Here, 8 is a capacitor whose capacity is C (μ
F). Weigh the mass of the entire measuring container after suction and weigh W
₂ (g). The triboelectric charge amount of this toner (mC / k
g) is calculated as follows:

[0166]

(Equation 2)

(2) Image Density The image density of the fixed image portion at a toner mass of 0.60 dg / m ² per unit area was measured using Macbeth RD918 (manufactured by Macbeth).

(3) Image quality of halftone part and solid part In the case of two-component development; contamination of the carrier / drum due to durability greatly affects the solid part image. By visual judgment, A, B,
C and D were evaluated.

In the case of a non-magnetic one component: The fusion of the toner on the sleeve due to the durability and the unevenness of the toner coating greatly affect the solid image, and the solid image quality of the obtained image on the transfer paper is visually determined. A, B, C, and D were evaluated.

(4) Fixability and Offset Resistance An appropriate amount of an external additive is externally added to the toner particles to obtain a toner. An unfixed image of the obtained toner is created by a commercially available copying machine.

The toner is evaluated for fixing and anti-offset properties by a heat roller external fixing device having no oil application function. Further, a fixed image for transparency evaluation is obtained.

At this time, the surface of both the upper roller and the lower roller is made of a fluororesin or rubber. Both upper and lower rollers have a diameter of 4
0 mm, and the transfer condition is SK
In the case of paper (manufactured by Nippon Paper), the nip is 5.5 mm and the fixing speed is 120 mm / sec. When the transfer material is an OHP sheet (manufactured by CG3300 / 3M), the nip is 5.5.
mm, the fixing speed is 35 mm / sec, and the temperature is adjusted every 5 ° C. within a temperature range of 100 ° C. to 250 ° C.

[0173] The fixing property was determined by comparing the image without offset with 5 points.
0 dg / m ^{2 with} a load of silbon paper [Lenz Cl
eaning Paper “desper (R)” (O
zuPaper Co. , Ltd. )], Rub twice,
The temperature at which the rate of decrease in density before and after rubbing is less than 10% is defined as the fixing start point.

In the offset resistance, the temperature at which no offset is visually observed is defined as a low-temperature non-offset starting point, and the maximum temperature at which no offset is generated by increasing the temperature is defined as a high-temperature non-offset end point.

(5) Degree of agglomeration After the screens were placed on a shaking table of a powder tester (manufactured by Hosokawa Micron Co., Ltd.) in the order of 150 μm, 75 μm, and 38 μm in order from the top, the amplitude of the shaking table was 0.4 m.
Adjust to m. Next, 5 g of the toner is weighed, gently placed on a 150 μm mesh screen located at the top, and subjected to vibration for 15 seconds. Thereafter, the weight of the toner remaining on each screen is measured, and the degree of aggregation is calculated according to the following equation. In addition, the smaller the value of the cohesion degree, the better the fluidity.

[0176]

## EQU00003 ## Degree of aggregation (%) = [mass (g) of toner on sieve with openings of 150 .mu.m / 5 g] .times.100 + [mass (g) of toner on sieve with openings of 75 .mu.m / 5 g] .times.100.times. (3/5) + [mass (g) / 5 g of toner on sieve with mesh of 38 μm] × 100 × (1/5)

[0177]

The present invention will be described below in more detail with reference to examples and comparative examples.

Example 1 An aqueous dispersion medium and a polymerizable monomer composition were prepared as described below.

Preparation of Aqueous Dispersion Medium 10 parts by weight of calcium phosphate was finely dispersed in 500 parts by weight of water, and the temperature was raised to 65 ° C. to obtain an aqueous dispersion medium.

Preparation of polymerizable monomer composition 90 parts by mass of styrene 9 parts by mass of 2-ethylhexyl acrylate 1 part by mass of methyl methacrylate 5 parts by mass of coloring agent (CI Pigment Blue 15: 3) 5 g t-butyl-salicylic acid metal compound 0.5 parts by mass-polyester resin 5 parts by mass-ester-based wax (melting point 60 ° C) 10 parts by mass-divinylbenzene 0.05 part by mass It was dissolved and dispersed to obtain a polymerizable monomer composition.

The polymerizable monomer composition prepared above was added to the aqueous dispersion medium prepared above with a high-speed rotary shearing stirrer CLEARMIX (manufactured by M Technique Co., Ltd.) under high stirring, and the mixture was formed for 10 minutes. Granulated. Here, 4 parts by mass of 2,2′-azobis (2,4-dimethylvaleronitrile) was added as a polymerization initiator, and granulation was further performed for 5 minutes. After completion of granulation, this is blended with Max Blend Tsubasa (Sumitomo Heavy Industries)
And the rotation speed was adjusted such that the number of passes N per unit time was 1 / sec. The polymerization was continued at an internal temperature of 65 ° C. When the conversion reached 90%, 1 part by mass of benzoyl peroxide was added over 60 seconds. At this time, T × N is 60.

The polymerization temperature was raised to 75 ° C., and the heating and stirring were continued for 5 minutes.
The polymerization was completed over a period of time. After completion of the polymerization reaction, residual monomers were distilled off under reduced pressure. After cooling, dilute hydrochloric acid was added to dissolve the dispersant, and solid-liquid separation, water washing, filtration and drying were performed to obtain polymerized toner particles.

When the cross section of the cyan toner particles was observed with a TEM, the release agent (wax) was obtained as shown in FIG.
Was successfully encapsulated in the outer shell resin.

100 parts by mass of the obtained cyan toner particles and 1.0 part by mass of a hydrophobic titanium oxide fine powder having a specific surface area of 100 m ² / g by the BET method were mixed to obtain a negatively triboelectrically charged cyan toner. Obtained.

A developer was prepared by mixing 8 parts by mass of the cyan toner with 92 parts by mass of an acryl-coated ferrite carrier, and a commercially available digital full-color copying machine (CLC500, manufactured by Canon Inc.) as shown in FIG. Using a modified machine (excluding the oil application mechanism of the fixing device), a continuous paper passing test (under high temperature and high humidity) of 10,000 sheets of cyan toner was performed.
Tables 1 and 2 show the physical properties and evaluation results of the toner.

<Examples 2 to 9> Under the conditions shown in Table 1, toners of Examples 2 to 9 were produced. Observation of the cross section of the cyan toner particles by TEM confirmed that the release agent was well encapsulated in the outer shell resin as shown in FIG. Tables 1 and 2 show the physical properties and evaluation results of the toner.

<Example 10> The colorant of Example 1 was replaced with C.I.
I. Pigment yellow 180, C.I. I. Pigment Red 122 and carbon black, respectively, and the same operation as in Example 1 was performed to obtain yellow, magenta and black toners, and to prepare a developer. Using a modified digital full-color copier (CLC500, manufactured by Canon) as shown in FIG. 4 (excluding the oil application mechanism of the fixing unit), continuous printing test of 10,000 sheets of full-color paper (under high temperature and high humidity)
As a result, stable image quality with solid uniformity was obtained.

<Example 11> Using the toner used in Example 10 and a non-magnetic one-component developing system as shown in FIG. 5, a continuous printing test of 5000 full-color sheets (under high temperature and high humidity) was performed. As a result, stable image quality with solid uniformity was obtained.

<Comparative Examples 1 to 5> Based on the conditions shown in Table 1, in the same manner as in Example 1, toners of Comparative Examples 1 to 5 were produced. Tables 1 and 2 show the physical properties and evaluation results of the toner.

[0190]

[Table 1]

[0191]

[Table 2]

[0192]

As described above, according to the toner production method of the present invention, even if the toner is left for a long time under high temperature and high humidity, it has excellent low-temperature fixability and anti-offset properties, and developability even when many sheets are used. A polymerized toner which does not impair (toner charge amount, image density) can be obtained.

[Brief description of the drawings]

FIG. 1 is a schematic explanatory view of an apparatus for measuring a triboelectric charge amount of a toner.

FIG. 2 is a schematic view of a cross section of a toner particle in which a release agent is included in an outer shell resin.

FIG. 3 is a schematic diagram of a developing device to which the toner of the present invention can be applied.

FIG. 4 is a schematic diagram for explaining a full-color or multi-color image forming method.

FIG. 5 is a schematic diagram for explaining another image forming method.

FIG. 6 is a schematic diagram illustrating an example of a developing device.

FIG. 7 is a schematic diagram illustrating an example of another developing device.

FIG. 8 is a schematic diagram illustrating an example of another developing device.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme court ゛ (Reference) G03G 9/08 365 G03G 9/08 384 321 331 (72) Inventor Katsuyuki Nonaka 3-30 Shimomaruko, Ota-ku, Tokyo No. 2 within Canon Inc. (72) Inventor Shinya Taniuchi 3-30-2 Shimomaruko, Ota-ku, Tokyo F-term within Canon Inc. (reference) 2H005 AA01 AA06 AB06 CA02 CA08 CA14 DA06 EA03 EA10 4J011 BB02 BB06 BB08 PA69 PA86 PA88 PB40 PC02 4J026 AA17 AA45 AB04 AB07 BA05 BA06 BA12 BA16 BA20 BA27 DB03 DB12 DB13 DB25 FA02 FA03 GA02

Claims (14)

[Claims] 1. A method for producing a polymerized toner obtained by polymerizing a polymerizable monomer composition containing at least a polymerizable monomer and a colorant, wherein a polymerization initiator is added a plurality of times, and The polymerization initiator added in the second and subsequent times is an organic peroxide, and the time of addition of the polymerization initiator added in the second and subsequent times is determined when the conversion of the polymerizable monomer is 70 to 99. %, And the polymerization initiator is added over 5 to 300 seconds. 2. The method according to claim 1, wherein the amount of the polymerization initiator added after the second time is 1 to 50 parts by mass with respect to 100 parts by mass of the polymerization initiator added for the first time. Item 10. The method for producing a polymerized toner according to Item 1. 3. The method for producing a polymerized toner according to claim 1, wherein the reaction temperature is increased by 5 ° C. or more before or after the addition of the polymerization initiator added after the second time. 4. The time T (second) required for adding the polymerization initiator added after the second time and the number of passes N (times / second) per unit time of the stirring blade used for the reaction are as follows: 10 ≦ T The method for producing a polymerized toner according to any one of claims 1 to 3, wherein the following relationship is satisfied. 5. The method according to claim 1, wherein the polymerization initiator added after the second time is a diacyl peroxide.
5. The method for producing a polymerized toner according to any one of claims 1 to 4. 6. The method for producing a polymerized toner according to claim 1, wherein the polymerization initiator added after the second time is benzoyl peroxide. 7. The method for producing a polymerized toner according to claim 1, wherein the polymerized toner has a THF-insoluble content of 5 to 50% based on the polymerized toner. 8. One hundred parts by mass of the polymerized toner,
The method for producing a polymerized toner according to any one of claims 1 to 7, further comprising 30 to 30 parts by mass of a low softening point substance. 9. The melting point of the low softening point substance is 40 to 110 ° C.
The method for producing a polymerized toner according to claim 8, wherein 10. The polymerizable monomer composition according to claim 1, wherein the polarizable resin is contained in an amount of 0.1 to 20 parts by mass based on 100 parts by mass of the polymerizable monomer. A method for producing the polymerized toner according to any one of the above. 11. The method according to claim 10, wherein the polar resin is a polyester resin. 12. An average circularity of 0.95 to 1.00 in a scattergram of circular equivalent diameter-circularity based on the number of toners measured by a flow-type particle image measuring apparatus. 12. The method for producing a polymerized toner according to any one of 1 to 11. 13. The method for producing a polymerized toner according to claim 1, wherein the polymerizable monomer composition is obtained by granulating and reacting in an aqueous medium. 14. A polymerizable monomer composition containing no polymerization initiator is granulated in an aqueous medium, and an initial polymerization initiator is added during granulation to obtain a reaction. The method for producing a polymerized toner according to claim 13.