JPS6273276A - Toner for electrophotography and its production - Google Patents

Abstract

PURPOSE:To obtain a spherical toner for electrophotography of which a resin for fixing consists of a novel polymerized compsn. and a process for producing the same by using such a combination in which a monomer dissolves in a reaction medium but the formed polymer thereof does not dissolve in the reaction medium as a radical polymerizable monomer and reaction medium. CONSTITUTION:This toner for electrophotography consists of the compsn. composed of the resin for fixing and a coloring agent dispersed in the resin. The resin for fixing consists of a mixture composed of a resin component I consisting of the radical polymerizable monomer (A) which can be made into a thermoplastic resin having insulating and fixing characteristics and a copolymer resin component II of the monomer (A) and a radical polymerizable monomer (B) having a charge controllable functional group. The toner consists of the polymerized compsn. in which the monomer (B) exists at a ratio of 0.1-10mol% based on the monomer (A) and the monomer (A) exists at 30-99mol% in the resin component I and at 1-70mol% in the resin component II. The toner for electrophotography having the spherical particles shaped to a uniform grain size is thus obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an electrophotographic toner and a method for producing the same. This invention relates to an electrophotographic toner of the form and a method for producing the same.

In particular, the present invention relates to a method for producing spherical electrophotographic toner containing a colorant and having a particle size within a range suitable for the toner in one step during the polymerization process of a fixing resin. The present invention also relates to a method for producing an electrophotographic toner that not only has excellent fluidity but also has various electrophotographic properties.

(Prior Art and Technical Problems of the Invention) In the field of electrophotography, toner is used for the purpose of visualizing electrostatic images. These toner particles are made of a composition in which a colorant and, if necessary, other additives such as a charge control agent are blended into a resin medium, and the particle size range is within a certain range, for example, from 1 to 30 μm. As the resin medium, a resin with the desired electrodetection properties and binding properties, such as styrene resin, is used, and as the colorant, carbon black or other organic or inorganic colored pigments are used. be done.

The most typical manufacturing method for electrophotographic toners consists of the steps of melt-kneading the aforementioned resin medium and colorant, cooling and pulverizing this kneaded composition, and classifying the pulverized product to align the particle size within a certain range. However, the yield of toner obtained by this pulverization and classification is extremely low, and a large amount of equipment is required for these operations, which makes the manufacturing cost of toner extremely high. In addition, because the shape of the particles obtained is irregular, the fluidity of the toner is generally low.
The drawback is that blocking is likely to occur.

Conventionally, many proposals have been accepted regarding the direct production of toner through the polymerization process of resin for toner. A typical method is to dissolve a soluble polymerization initiator in a water-insoluble monomer, add additives such as a coloring agent, and then mix this composition with a suitable dispersant, such as a water-soluble polymer. , an inorganic powder, a surfactant, etc. are suspended in an aqueous solution by high-speed shear stirring, and the suspension is polymerized to produce colored polymer particles. However, in this suspension polymerization method, the particle size of the final toner is determined by the state of suspension of the monomer composition in water, and the particle size distribution is determined by adding the monomer composition into water or stirring it. Depending on the situation, it is very broad and it is difficult to obtain particles with a single particle size. In general, in this suspension polymerization method, the number 1
It is imperative to obtain particles with a particle size of 1 to 30 μm, which are useful as toners for developers, and produce only coarse particles of about 0 μm to several sizes. Of course, it is possible to increase the blending amount of the dispersant to make the particle size of the produced toner finer, but in this case, the dispersant is contained in the toner and the toner tends to be sensitive to humidity, etc. This tends to cause deterioration of electrophotographic properties. In order to prevent this, special post-processing operations are required and the number of steps is large, making it impractical.

Furthermore, the so-called emulsion polymerization method is known as a method for producing polymer particles with relatively uniform particle size, but the particles obtained by this polymerization method are fine particles with a particle size of 1 7111 or less. Furthermore, it is difficult to obtain a colored resin for toner directly during the polymerization process, as it requires a step to remove the emulsifier and the like after the polymerization.

Conventionally, a styrene or acrylic monomer having polar groups such as an amino group or a hydroxyl group and a coloring agent are suspended and polymerized in the presence of an acid-soluble inorganic compound, and the resulting suspension is colored by acid treatment. A method for producing polymeric fine particle toner is also already known (Japanese Patent Publication No. 14895/1983). However, this method not only requires the troublesome operation of dissolving and removing inorganic compounds, but also polymerizes a part of the polymerizable monomer while being dissolved in the aqueous phase during the dispersion and polymerization steps, so-called Similar to emulsion polymerization, this method has the disadvantage that extremely fine polymer particles of 1 μm or less are produced as by-products.

(Gist and Object of the Invention) The present inventors first dissolved or dispersed a radically polymerizable monomer and a colorant in a reaction medium, and then added the radically polymerizable monomer and the reaction medium to the monomer. The polymer should be selected so that it dissolves in the reaction medium, but the resulting polymer does not dissolve in the reaction medium, and when this polymerization system is polymerized in the presence of a radical polymerization initiator, the combination of resin and colorant We have found that it is possible to obtain a toner consisting of substantially spherical particles with an average particle size of 1 to 30 μm. By polymerizing and continuing the polymerization by adding a radically polymerizable monomer having a charge-controlling functional group in the middle of the polymerization, uniformly spherical particles of a fixing medium having a new polymer composition can be obtained. It has been found that a toner consisting of particles can be obtained and that this spherical toner has an excellent combination of fixing properties, charge control and flowability.

That is, an object of the present invention is to provide a spherical electrophotographic toner in which the fixing resin is composed of a novel polymeric composition, and a method for producing the same.

Another object of the present invention is to provide an electrophotographic toner having excellent particle size uniformity and a combination of excellent fixing properties, charge control action, and fluidity, and a method for producing the same.

Still another object of the present invention is to provide spherical charge-controlling colored resin particles having a particle size configuration suitable for use as a toner and which does not substantially disrupt the electrophotographic properties of the toner during the polymerization process of the resin. An object of the present invention is to provide a method for producing an electrophotographic toner that can be directly produced.

Still another object of the present invention is to control the particle size of the colored resin during the polymerization process without containing fine particles and to have a particle size of 1 to 30 μm suitable for toner.
It is an object of the present invention to provide a method for producing a charge controllable colored toner, which can be stably carried out within the range of m and also maintain a uniform particle size distribution.

Still another object of the present invention is to provide a method for obtaining I.ner particles having the above characteristics by relatively simple means.

(Structure of the Invention) According to the present invention, there is provided an electrophotographic toner comprising a composition of a fixing resin and a colorant dispersed in the resin, wherein the fixing resin has an insulating property and a fixing thermoplastic. A resin component (1) consisting of a radically polymerizable monomer (A) that can become a resin, and a radically polymerizable monomer (B) having a charge control functional group and the monomer (A).
) with copolymer resin component II, and based on the monomer (A), the monomer (
B) is present in an amount of 0.1 to 10 mol%, monomer (A
30 to 99 mol % of the polymer composition is present in resin component (1) and 1 to 70 mol % is present in resin component II, thereby providing an electrophotographic toner in the form of spherical particles with uniform particle size.

According to the present invention, in the method for producing an electrophotographic toner comprising a fixing resin, a colorant dispersed in the resin, and a composition, a radically polymerizable monomer that can be an insulating and fixing thermoplastic resin is used. A) and a coloring agent are dissolved or dispersed in a reaction medium, where the monomer (A) and the reaction medium are dissolved in the reaction medium, but the resulting resin is not reacted. The monomer (A
) Polymerization is carried out so that 30 to 99 mol % of the total is converted into a polymer, and 0.1 to 10 mol % of a charge-controlling functional group-containing radically polymerizable monomer is added to this polymerization system per monomer (A). Adding body (B) continuously or in one or multiple stages,
A method for producing an electrophotographic toner is provided, which is characterized in that polymerization is continued.

(Characteristics and Effects of the Invention) The characteristics of the present invention will be explained first, starting with the method, so that it can be easily understood.

In the present invention, a radically polymerizable monomer and a colorant are dissolved or dispersed in a reaction medium (solvent), and polymerization is performed in the presence of a radical initiator. An important feature is to use a combination in which the monomer is soluble in the reaction medium, but the resulting polymer is not soluble in the reaction medium; under the conditions of this combination, the normal The particle size is larger than the resin particles obtained by emulsion polymerization, and the particle size is finer than the resin particles obtained by ordinary suspension polymerization, and it is possible to obtain a colored resin that is within the particle size range suitable for toner particles. This is based on this knowledge.

Generally, polymerization that proceeds in a solution is called solution polymerization, but in this solution polymerization, the produced polymer is dissolved in the solvent, whereas in the method of the present invention, the produced polymer is dissolved in the solvent, that is, the reactant. They are distinguished by the fact that they do not dissolve in the medium.

In the present invention, the above-mentioned polymerization method produces colored particles whose particle size range is within the above-mentioned specific range and whose particle size distribution is relatively sharp, although the reason is not limited thereto, but is as follows. considered to be a thing. That is, in the polymerization system of the present invention, at the initial stage of polymerization, polymerization is initiated within the reaction medium, and the growing polymer chains coalesce with colorant particles having a large specific surface area dispersed in the polymerization system.

During the middle stage of polymerization, that is, after the polymer particles are formed, polymerization is initiated at the interface of the polymer particles or even inside the polymer particles under conditions where the monomer is easily incorporated into the formed polymer particles. It is believed that the polymerization form has both emulsion polymerization and suspension polymerization.

For this reason, the colored polymer particles produced are intermediate between resin particles produced by emulsion polymerization and resin particles produced by suspension polymerization.
It is believed that the toner has a particle size within a suitable range. In addition, when the diameter of the polymer particles in the polymerization system is
It is believed that the growth rate of a polymer particle is inversely proportional to its surface area 4πr2. On the other hand, the volume of polymer particles (4/3)
πr3 increases in proportion to polymerization time. Therefore, fine polymer particles have a high rate of increase in particle size, while large polymer particles have a low rate of increase, resulting in a relatively sharp particle size distribution and uniform particle size. A further advantage is that the colored polymer particles that grow as the polymerization progresses are maintained in a nearly perfect spherical shape by the interfacial tension between them and the reaction medium.

In the present invention, the radically polymerizable monomer (A) that can become an insulating and fixing thermoplastic resin is partially polymerized, and then the radically polymerizable monomer (A) having a charge controllable functional group (hereinafter also referred to as a polar group) is polymerized. The second feature is that polymerization is continued by adding compound (B) to the system.

That is, when polymerization is carried out with the charge-controlling functional group-containing monomer (B) coexisting in the reaction system from the beginning, the polymer fine particles generated in the initial stage have a surface electrostatic charge based on the charge of the functional group. Due to the repulsive force, the dispersion is stabilized in the polymerization system, moderate aggregation and coalescence of the fine particles occur, and they do not coalesce with the coloring agent until the final stage of polymerization. The functional group is not contained in the polymer toner particles, or even if it is contained, the concentration thereof is extremely low.

When used as a toner, it is necessary to remove such uncolored resin particles, and as the content of polar groups in the toner particles decreases compared to the amount blended, the expected chargeability imparting effect may not be achieved. The disadvantage is that it cannot be obtained. Further, there is also a drawback that the effect of imparting chargeability is non-uniform for each particle. Moreover, since the above-mentioned polar group-containing monomer (B) is relatively expensive, it is also economically disadvantageous.

According to the present invention, a monomer (A) that can be used as an insulating and fixing resin is first polymerized to produce polymer particles containing a colorant, and then a polar group-containing monomer is added to the system. By adding (B) and continuing the polymerization, the polar group-containing monomer (B) is efficiently incorporated into the toner particles, and the polymerization and spheroidization of the particles proceed, resulting in an uncolored state. It becomes possible to suppress the residual amount of polymer fine particles to an extremely small level and to efficiently contain a polar group-containing monomer in colored particles useful as toners at a uniform concentration. In addition, it is economically advantageous because the process of separating and removing uncolored fine particles can be omitted, and the amount of expensive polar group-containing monomers used can be saved.

Of course, as long as the above-mentioned polymerization form can be maintained, it goes without saying that even if a part of the polar group-containing monomer (B) is added at the initial stage of polymerization, this essentially corresponds to the content of the present invention.

As used herein, a polymeric composition is defined as a composition obtained by polymerization, as opposed to a simple blend of multiple types of polymers, and this polymeric composition includes a mixture of multiple types of polymer components. , block copolymers thereof, or combinations thereof.

The fixing medium in the toner of the present invention is a monomer (
It is important that the resin component I consisting of A) and the copolymer resin component ■ of the monomer (A) and the charge control functional group-containing monomer (B) are contained in the form of a mixture. It is a characteristic,
Some of these may be combined in the form of a block or graft copolymer. That is, the resin component I is composed of a polymer chain consisting of the following formula % formula %, while the resin component II is composed of a random copolymer chain consisting of the following formula % formula %, and the resin component Part (2) and part of the copolymer resin component H exist in the form of a block or graft copolymer.

That is, since the copolymer resin component (2) has the above-mentioned chain structure, this component (2) has a high affinity for the resin component (I), so that the spherical toner particles of the present invention have extremely uniform resin composition for each particle. It has the characteristic of being Furthermore, a sufficient charge control effect is achieved with a relatively small amount of monomer (B), and it also has good fixing properties, is not sensitive to humidity, has a uniform particle size, and has excellent fluidity. There is an advantage.

The charge control functional group-containing monomer (B) has a sufficient charge control effect on the toner in a very small amount of 0.1 to 10 mol%, particularly 0.5 to 5 mol%, based on the monomer (A). It will be done. If it is less than the above range, the charge control effect tends to be lower than in the case of the present invention, while if it exceeds the above range, it becomes humidity sensitive, resulting in a decrease in charging characteristics at high humidity and a decrease in fluidity. It is easy to cause deterioration, etc. 30 to 99 mol%, in particular 50 to 95 mol%, of the monomer (A) is incorporated into the resin line (III), while 1 to 70 mol%, in particular 5 to 50 mol%, is incorporated into the copolymer resin line (H). It is also important that the monomer (B) is incorporated into the spherical particles with low efficiency outside these ranges.

(Thus, the colored particles obtained by the present invention do not require classification operations, have little loss of raw materials, have extremely high productivity, and have excellent fluidity as a powder, anti-blocking properties, and even fixing properties. , has excellent charge control effects, etc., and further has the remarkable advantage that by suppressing the amount of dispersant and activator used, there is virtually no factor inhibiting the electrophotographic properties of the toner.

(Description of preferred embodiments of the invention) ■ In the present invention, the monomer (A) used is radically polymerizable, and the resulting polymer has the fixing properties required for toner. One or a combination of two or more monomers having systemic unsaturation may be used subject to the aforementioned limitations. Suitable examples of such monomers include vinyl aromatic monomers, acrylic monomers, vinyl ester monomers, vinyl ether monomers, diolefin monomers, and monoolefin monomers. body etc.

As a vinyl aromatic monomer, R4 is a hydrogen atom, a lower alkyl group, or a halogen atom, and R2 is a hydrogen atom, a lower alkyl group, a halogen atom, an alkoxy group, a nitro group, or a vinyl group. , vinyl aromatic hydrocarbons such as styrene, α-methylstyrene, vinyltoluene, α-chlorostyrene, o
-1m-1p-chlorostyrene, p-ethylstyrene,
Divinylbenzene may be used alone or in combination of two or more, and the other monomers mentioned above may include the following.

CHZ = C-c o -o -R4-----1-
------- (2) In the formula, R3 is a hydrogen atom or a lower alkyl group, R4 is a hydrogen atom, a hydrocarbon group having up to 12 carbon atoms,
Acrylic monomers that are hydroxyalkyl groups or vinyl ester groups, such as methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, phenyl acrylate, methyl methacrylate, hexyl methacrylate,
2-ethylhexyl methacrylate, β-hydroxyacrylate) R4:f:, thyl, γ-hydroxyacrylate furovir, δ-hydroxybutyl acrylate, β-hydroxyethyl methacrylate, ethylene glycol dimethacrylate, tetraethylene glycol Dimethacrylic acid ester, etc.

CH2=CH”oc-R,,--------1-------(3)
In the formula, R2 is a hydrogen atom or a lower alkyl group, vinyl esters such as vinyl formate, vinyl acetate, vinyl propionate, etc.

Formula, CH, = CH o -R,
--In the formula (4), R6 is a monovalent hydrocarbon group having up to 12 carbon atoms, vinyl ethers such as vinyl methyl ether, vinyl ethyl ether, vinyl-n-butyl ether, vinyl phenyl ether, vinyl cyclohexyl ether, etc.

formula, R? R.

CHz=CC=CHRq ---------(5) In the formula, R? , Re and Rq are each a hydrogen atom, a lower alkyl group or a halogen atom, and diolefins, particularly butadiene, isoprene, chlorobrene and the like.

Formula, R1゜GHz = CR+ + −−−−−−−−−−−
---In formula (6), each of RIG and R1+ is a hydrogen atom or a lower alkyl group, monoolefins, especially ethylene, propylene, isobutylene, butene-1, pentene-1, 4-methylpentene-1 etc.

In the present invention, the radically polymerizable monomer (A) should be such that the resulting polymer is well dissolved in the monomer itself, especially in order to equalize the particle size of the colorant resin particles. desirable. Such monomers include monovinyl aromatic monomers, especially styrenes, or acrylic monomers, as well as combinations thereof.

As the colorant, various pigments and dyes (hereinafter simply referred to as coloring pigments) for coloring the toner are used.

Suitable examples of colored pigments are:

Black pigments carbon black, acetylene black, lamp black, aniline blank.

Yellow pigment yellow lead, zinc yellow, cadmium yellow, yellow iron oxide, mineral fast yellow, nickel titanium yellow, navel yellow, naphthol yellow S1 Hansa Yellow G1
Hansa Yellow 10G1 Benzidine Yellow 01 Benzidine Yellow GR, Ginoline Yellow Lake, Permanent Yellow NCG, Tartrazine Lake.

Orange pigments red yellow lead, molybdenum orange, permanent orange GTR, pyrazolo orange, palkan orange, indanthrene brilliant orange RK, benzidine orange G1 indanthrene brilliant orange GK and red pigments red pigment red pigment, cadmium red, red lead, mercury sulfide Cadmium, Permanent Red 4R, Lysol Resod, Pyrazolone Red, Watching Red Calcium Salt, Lake Red D, Brilliant Carmine 6B, Eosin Lake, Rhodamine Lake B, Alizarin Lake, Brilliant Carmine 3B.

Purple pigment Manganese Purple, Fast Violet B, Methyl Violet Lake.

Blue pigments navy blue, cobalt blue, alkali blue lake, Victoria blue lake, phthalocyanine blue, metal-free phthalocyanine blue, cyanine blue partially chlorinated product, first sky blue, indanthremble-B
C.

Green pigment chrome green, chromium oxide, pigment green B1
Malachite Green Lake, Final Yellow Green G0 White pigment zinc white, titanium oxide, antimony white, zinc sulfide.

Extender pigments Palite powder, barium carbonate, clay, silica, white carbon, talc, alumina white.

As a magnetic material pigment, conventionally, for example, triiron tetroxide (PE3
on), iron sesquioxide (7-F13203), zinc iron oxide (ZnFezOt), yttrium iron oxide (Y3Fe,
01□), cadmium oxide (CdFe204), iron gadolinium oxide (Gd3Fe5012), iron steel oxide (Cu
FegO4), iron oxide complex (PbFe+ 2019), neodymium iron oxide (NdFeO4), barium iron oxide (B
aFe+ 2019), magnesium iron oxide (MgFe
20J, iron manganese oxide (MgFe20J), lanthanum iron oxide (LaPeOz), iron powder (Fe), cobalt powder (
CO), nickel powder (Ni), and the like are known, but any of these known fine powders of magnetic materials can be used in the present invention.

On the other hand, the charge control functional group-containing monomer (B) may be a sulfonic acid, phosphoric acid, or carboxylic acid type anionic group, or a primary, twelfth, or tertiary amino group, or a quaternary ammonium group. Examples include radically polymerizable monomers having an electrolytic group such as a cationic group, and suitable examples thereof are as follows.

Styrene sulfonic acid, sodium styrene sulfonate,
2-acrylamido 2-methylpropanesulfonic acid, 2
-Acid phosphooxypropyl methacrylate, 2-
Acid phosphooxyethyl methacrylate, 3-chloro 2-acid phosphooxypropyl methacrylate,
Acrylic acid, methacrylic acid, fumaric acid, crotonic acid, tetrahydroterephthalic acid, itaconic acid, aminostyrene, aminoethyl methacrylate, aminopropyl acrylate, diethylaminopropyl acrylate, r-N
-(N',N'-diethylaminoethyl)aminopropyl methacrylate, trimethylammoniumpropyl methacrylate-1.

In the present invention, additive components that are desirable to be included in the toner can be blended into the polymerization system prior to polymerization. For example, in order to add an anti-offset effect to the toner, a release agent such as low molecular weight polyethylene, low molecular weight polypropylene, various waxes, silicone oil, etc. can be included.

Polymerization method According to the invention, an organic solvent is used as the reaction medium which dissolves the monomers but not the resulting polymer. Furthermore, it is desirable that the organic solvent be easily volatile in order to prevent the adverse effects of residual solvent in the toner.

Although the specific solvent name should be determined depending on the type of monomer and its polymer, generally speaking, suitable organic solvents include alcohols, cellosolves, ketones, or hydrocarbons. Furthermore, these compounds can be used as a mixed solvent with other molar solvents that are compatible with each other, or with water, but the present invention is not limited thereto. As alcohols, lower alcohols such as methanol, ethanol, and propatool are used; as cellosolves, methyl cellosolve and ethyl cellosolve are used; as ketones, acetone, methyl ethyl ketone, and methyl butyl ketone are used; as hydrocarbons, n -hexane, n-heptane, cyclohexane and the like.

As the polymerization initiator, ab compounds such as azobisisobutyronitrile, cumene hydroperoxide, t-butyl hydroperoxide, dicumyl peroxide, di-t-
Peroxides such as butyl peroxide, hendiyl peroxide, lauroyl peroxide, etc., which are soluble in the mixture of the monomer and the medium, are used. In addition, combinations of ionizing radiation such as gamma rays, accelerated electron beams, ultraviolet rays, and various photosensitizers are also used.

According to the present invention, first, the monomer (A) is charged into the polymerization system,
Initiate polymerization.

The amount of monomer charged is preferably such that the monomer is present in the reaction medium in an amount of 1 to 50% by weight, particularly 5 to 30% by weight, based on the reaction medium. If the colorant is blended in the amount contained in the toner resin, it is generally appropriate to range from 1 to 30% by weight, particularly from 3 to 20% by weight, based on the amount of monomers charged. In addition, when a magnetic material is used as a pigment, it is generally 5 to 300% by weight, particularly 10 to 2% by weight, based on the amount of monomer charged.
50% by weight is suitable.

The amount of the initiator, such as an azo compound or peroxide, may be a so-called catalyst appropriate amount, and is generally preferably used in an amount of 0.1 to 10% by weight based on the monomers charged. The polymerization temperature and time may be those known in the art, and generally polymerization at a temperature of 40 to 100°C for 1 to 50 hours is sufficient. Incidentally, the reaction system may be stirred gently so that a homogeneous reaction occurs as a whole;
Furthermore, in order to prevent polymerization from being inhibited by oxygen, polymerization may be carried out by replacing the reaction system with an inert gas such as nitrogen.

The monomer (A) and the polymerization initiator may be charged in their entirety,
Alternatively, a portion may be charged and the remaining portion may be supplied stepwise or continuously.

According to the present invention, the monomer (B) is removed at a stage midway through the polymerization of the monomer (A), that is, at a stage when the polymerization rate of the monomer (A) reaches 30 to 99%, particularly 50 to 95%. ) is added to the polymerization system. The monomer (B) may be added in one step, in multiple steps, or even continuously.

Instead of adding monomer (B) alone, monomer (A)
Naturally, it can be added in the form of a mixture with.

By adding monomer (B) during the polymerization of monomer (A), monomer (B) can be efficiently absorbed into the growing polymer particles of monomer (A). It becomes possible.

Since the polymerized product after the reaction is obtained in the form of granules having the particle size range described above, the resulting particles are filtered, washed with the above solvent if necessary, and dried to obtain colored particles for toner.

The colored particles for toner are sprinkled with carbon black, hydrophobic silica, etc., if necessary, to form a final toner.

Further, in the production of toner, a dispersion stabilizer can also be used if necessary. Such dispersion stabilizers include polymers soluble in the medium, such as polyvinyl alcohol, methylcellulose, ethylcellulose, polyacrylic acid, polyacrylamide, polyethylene oxide, polyvinylpyrrolidone, poly(hydroxystearic acid-g-methacrylic acid). A methyl-co-methacrylic acid) copolymer, a nonionic or ionic surfactant, etc. are used as appropriate.

The invention is illustrated by the following example.

Example 1 8 g of polyacrylic acid was dissolved in 800 mj+ of ethanol, and 80 g of styrene and 2 -butyl methacrylate were added to the solution.
0 g, carbon black (Printex L: manufactured by Degussa) 5 g and azobisisobutyronitrile 1 g were added, and the mixture was heated at 150 r under nitrogen flow in a separable flask No. 11.
The reaction was carried out at 80° C. with stirring at , p, m, and when the polymerization rate reached 80%, 1 g of 2-acid phosphooxyethyl methacrylate was added, and the polymerization was completed over 15 hours. When the polymer was observed with an optical microscope, it was approximately 1
They were spherical black particles with a diameter of 0 μm. The polymer is separated by sedimentation,
After washing with ethanol three times, it was dried to obtain 96 g of toner. It is believed that a small amount of polymer particles still remained in the supernatant during the sedimentation separation, and that these were removed during the washing process, resulting in a decrease in yield. The particle size distribution of this toner was sharp, as shown in Table 1 as measured by a Coulter counter, and the average particle size was 10.4 μm. This toner was mixed with an iron powder carrier (EFV250/400, manufactured by Nippon Tetsuko Co., Ltd.), and the amount of charge was measured by a blow-off method to obtain the values shown in Table 2. When this toner was put into a m1ta DC-211 copying machine and copied, clear images were obtained, and there was almost no toner scattering in the developing device.

Comparative example: 8 g of polyacrylic acid was dissolved in 800 mA of ethanol,
To this, 80 g of styrene, 20 g of 〇-butyl methacrylate
g, 2-acid phosphooxyethyl methacrylate 1
5 g of g1 carbon blank (Printex L: manufactured by Degussa) and 1 g of azobisisobutyronitrile were added, and the mixture was heated for 150 r under a nitrogen stream in a separable flask No. 11.
The reaction was carried out at 80°C while stirring at , p, +n, and the polymerization was completed over time. When the polymer was observed under an optical microscope, it was found to be spherical black particles of about 10 μm. The polymer was separated by sedimentation, washed three times with ethanol, and then dried to obtain 80 g of toner. It is believed that a small amount of polymer particles still remained in the supernatant during the sedimentation separation, and that these were removed during the washing process, resulting in a decrease in yield. The particle size distribution of this toner was sharp, as shown in Table 1 as measured by a Coulter counter, and the average particle size was 9.5 μm.

As shown in Table 2, the amount of charge of this toner was lower than that of the toner obtained in Example 1. This toner is
When the image was copied using a DC-211 copying machine, a clear image was obtained, but some toner was scattered inside the developing unit.

Example 2 8 g of polyacrylic acid was dissolved in 780 mj2 of methanol, and 20 g of styrene and 5 -butyl methacrylate were added to the solution.
g, add 5 g of carbon black (Printex L: manufactured by Degussa) and 1 g of azobisisobutyronitrile,
The temperature was raised to 65° C. in a separable flask (No. 1), and 60 g of styrene and 15 g of n-butyl methacrylate were added dropwise over 10 hours while stirring at 150 r, p, +w under a nitrogen stream. The polymerization rate after the completion of dropping had reached about 70%. Here, 5% sodium styrene sulfonate aqueous solution 2
0.5 g of 0ml117 zobisisobutyronitrile was added and the reaction was further carried out for 10 hours to complete the polymerization.

When the polymer was observed under an optical microscope, it was found to be spherical black particles of about 10 μm. The polymer was separated by sedimentation, washed three times with methanol, and then dried to obtain 106 g of toner.

The yield was 100%. The particle size distribution of this toner is sharp, as shown in Table 1 as measured by a Coulter counter, and the average particle size is 9.
It was 7 μm. The charge amount of this toner was measured by the blow-off method, and the values shown in Table 2 were obtained. m1taDc this toner
When the image was copied using a 211 copying machine, a clear image was obtained, and there was almost no toner scattering in the developing device.

Comparative Example 2 Methanol 180mI! 8 g of polyacrylic acid was dissolved in the solution, and 80 g of styrene and 2 g of n-butyl methacrylate were dissolved in the solution.
0g, sodium styrene sulfonate aqueous solution (5%) 2
0ml carbon blank (Printex L: manufactured by Degussa) 5g and azobisisobutyronitrile 1.5g
Add g, 17! The polymer was heated to 65° C. in a separable flask and observed under an optical microscope while stirring at 150 r, p, a+ under a nitrogen stream, and it was found to be spherical black particles of about 10 μm. The polymer was separated by sedimentation, washed three times with methanol, and then dried to obtain 90 g of toner.

Note that during sedimentation separation, a small amount of polymer particles still remained in the supernatant, and it is thought that the yield decreased because these were removed during the washing process.

The particle size distribution of this toner was sharp, as shown in Table 1 as measured by a Coulter counter, and the average particle size was 10.0 μm. As shown in Table 2, the amount of charge of this toner was lower than that of the toner obtained in Example 2. This toner is m1taDC2
11 When I put it in a copying machine and made a copy, a clear image was obtained, but toner was scattered inside the developing device.

Table 1 Table 2 that's all

Claims (2)

[Claims] (1) An electrophotographic toner comprising a composition of a fixing resin and a colorant dispersed in the resin, wherein the fixing resin contains a radically polymerizable monomer that can be an insulating, fixing thermoplastic resin. A resin component I consisting of the monomer (A) and the monomer (A)
and a radically polymerizable monomer having a charge controllable functional group (
A mixture of copolymer resin component II of B), and a mixture of monomers (A) and copolymer resin component II of
B) is present in an amount of 0.1 to 10 mol%, monomer (A
), 30 to 99 mol% of resin component I, 1 to 70 mol% of
Mol% is an electrophotographic toner consisting of a polymeric composition present in resin component II and in the form of spherical particles with uniform particle size. (2) In the method of manufacturing an electrophotographic toner comprising a fixing resin, a colorant dispersed in the resin, and a composition, a radically polymerizable monomer (A
) and a coloring agent are dissolved or dispersed in a reaction medium, and the monomer (A) and the reaction medium are dissolved or dispersed in the reaction medium. The monomer (A
) Polymerization is carried out so that 30 to 99 mol % of the total is converted into a polymer, and 0.1 to 10 mol % of a charge-controlling functional group-containing radically polymerizable monomer is added to this polymerization system per monomer (A). Adding body (B) continuously or in one or multiple stages,
A method for producing an electrophotographic toner characterized by continuing polymerization.