JP4198619B2 - Toner for developing electrostatic image, image forming apparatus, process cartridge - Google Patents

Description

  The present invention relates to a toner for developing an electrostatic image that visualizes an electrostatic image formed on the surface of a photoreceptor in electrophotography or electrostatic recording, a developer using the toner, and the toner or developer. The present invention relates to an image forming apparatus to be used.

Conventionally, in an electrophotographic apparatus, an electrostatic recording apparatus, or the like, an electric or magnetic latent image is visualized with toner. For example, in electrophotography, an electrostatic charge image (latent image) is formed on a photoconductor that is an image carrier, and the latent image is developed with toner to form a toner image. The toner image is usually transferred onto a transfer material such as paper and fixed by a method such as heating.
Toner used for electrostatic image development is generally colored particles in which a binder, a colorant, a charge control agent, and other additives are contained in a binder resin. There is a suspension polymerization method.
In the pulverization method, a colorant, a charge control agent, an offset preventing agent and the like are melt-mixed in a thermoplastic resin and uniformly dispersed, and the resulting composition is pulverized and classified to produce a toner. According to the pulverization method, a toner having some excellent characteristics can be produced, but there is a limitation in the selection of the toner material. For example, the composition obtained by melt mixing must be capable of being pulverized and classified by economically usable equipment. From this requirement, the melt-mixed composition must be made sufficiently brittle. Therefore, when the above composition is actually pulverized into particles, a high-range particle size distribution is likely to be formed, and when attempting to obtain a copy image with good resolution and gradation, for example, the particle size There is a disadvantage that the fine powder of 5 μm or less and the coarse powder of 20 μm or more must be removed by classification, resulting in a very low yield. Further, in the pulverization method, it is difficult to uniformly disperse the colorant, the charge control agent, and the like in the thermoplastic resin. The uneven dispersion of the compounding agent adversely affects the fluidity, developability, durability, image quality and the like of the toner.
In recent years, in order to overcome these problems in the pulverization method, a toner production method by a suspension polymerization method has been proposed and implemented. A technique for producing a toner for developing an electrostatic latent image by a polymerization method is known. For example, toner particles are obtained by a suspension polymerization method. However, the toner particles obtained by the suspension polymerization method are spherical and have a drawback of poor cleaning properties. Development / transfer with a low image area ratio results in a small amount of residual toner, and poor cleaning does not pose a problem. However, images with a high image area ratio, such as photographic images, and untransferred images formed due to poor paper feed, etc. Toner may be generated on the photoconductor as untransferred toner, and if accumulated, the image may be soiled. In addition, the charging roller that contacts and charges the photosensitive member is contaminated, and the original charging ability cannot be exhibited. For this reason, Patent Document 1 discloses a method of obtaining irregularly shaped toner particles by associating resin fine particles obtained by an emulsion polymerization method. However, in the toner particles obtained by the emulsion polymerization method, a large amount of the surfactant remains not only on the surface but also inside the particles even after the water washing step, and the environmental stability of the toner charging is impaired. The amount distribution is widened, and the background stain of the obtained image becomes poor. Further, the remaining surfactant contaminates the photoreceptor, the charging roller, the developing roller, etc., and the original charging ability cannot be exhibited.

On the other hand, Patent Document 2 proposes a new production method called a dissolution suspension method (EA: Emulsion-Aggregation method). This method is a method of granulating from a polymer dissolved in an organic solvent, etc., while the suspension polymerization method forms particles from monomers, and has advantages such as expansion of the resin selection range and polarity controllability. Cite. Although the toner structure control (core / shell structure control) is possible, the shell structure is a resin-only layer intended to reduce the exposure of pigments and wax to the surface. It is disclosed that the state is not devised, and that it does not have such a structure. Therefore, although the shell structure is used, the surface of the toner is a normal resin and is not particularly devised. When aiming at fixing at a lower temperature, it is not sufficient in terms of heat-resistant storage stability and environmental charge stability.
Moreover, it is common to use a styrene-acrylate copolymer for any of the suspension polymerization method, emulsion polymerization method, and dissolution suspension method, and polyester resins have difficulty in particle formation and have a particle size and particle size distribution. It was difficult to control the shape. In addition, there was a limit to fixability when aiming at lower temperature fixing.
On the other hand, the use of a polyester modified with a urea bond for the purpose of heat-resistant storage stability and low-temperature fixing is also described in Patent Document 3, but the surface is not particularly devised, and the environment is particularly severe. The problem was not sufficient in terms of charging stability.

  In the field of electrophotography, high image quality has been studied from various angles, and among them, the recognition that toner diameter reduction and spheroidization are extremely effective is increasing. However, as the diameter of the toner is reduced, the transferability and the fixing property are lowered, and a tendency to become a poor image is observed. On the other hand, Patent Document 4 describes that transferability is improved by making the toner spherical. Under such circumstances, further speeding up of image formation is desired in the field of color copiers and color printers. For speeding up, the “tandem method” is effective as described in Patent Document 5. The “tandem method” is a method of obtaining a full-color image on a transfer sheet by sequentially superimposing and transferring an image formed by an image forming unit onto a single transfer sheet conveyed to a transfer belt. A tandem color image forming apparatus has a variety of transfer papers that can be used, has high quality of a full color image, and has excellent characteristics that a full color image can be obtained at a high speed. In particular, the characteristic that a full color image can be obtained at a high speed is a characteristic that is not found in other color image forming apparatuses. On the other hand, attempts have been made to achieve high speed while improving image quality using spherical toner. However, in order to cope with higher speeds, quick fixability is required, but a toner having both good fixability and low temperature fixability with a spherical toner has not been realized so far.

Japanese Patent No. 2537503 Japanese Patent No. 3141784 Japanese Patent Laid-Open No. 11-133667 JP 9-258474 A JP-A-5-341617

  SUMMARY OF THE INVENTION In view of the above problems, the present invention provides a developer capable of forming a stable image that is compatible with a low-temperature fixing system, has good offset resistance, and does not contaminate the image. An object is to provide an electrophotographic image forming apparatus.

As a result of intensive studies to solve the above problems, the present inventors have at least an organic solvent phase in which a functional group-containing polyester resin is dissolved, an active hydrogen-containing compound, and a colorant. Dispersed in a dispersed aqueous medium phase to cause elongation reaction and / or cross-linking reaction between the functional group-containing polyester resin and the active hydrogen-containing compound, thereby forming particles from the resulting dispersion It has been found that a toner base that is compatible with a low-temperature fixing system and has good offset resistance can be obtained by dispersing a tertiary amine compound in an organic solvent phase. The present invention has been completed based on the findings.
The present invention includes at least an isocyanate group-containing organic solvent phase polyester resin is dissolved, and an amine, and a colorant, the resin particles are dispersed in an aqueous medium phase which is dispersed, isocyanate group-containing polyester A toner for developing an electrostatic charge image that causes an elongation reaction and / or a cross-linking reaction between a resin and an amine and forms particles from the resulting dispersion, wherein a tertiary amine compound is added to the organic solvent phase. It is a toner for developing an electrostatic image characterized by containing.

The present invention, the tertiary amine compound is electrostatic toner for developing electrostatic images which you express by the following structural formula (I).

In the present invention, in the organic solvent phase, a non-reactive polyester is further dissolved together with the functional group-containing polyester resin, and the weight ratio of the functional group-containing polyester resin to the non-reactive polyester is 5/95 to 75/25 toner for developing electrostatic images.
The present invention preferably has a volume average particle size of the toner particles are toner for developing electrostatic images you being a 3 to 8 [mu] m.
The present invention is a toner for developing electrostatic images you wherein the Dv / Dn of the toner particles is 1.25 or less.
The present invention has an average circularity of the toner particles are toner to that developing electrostatic images, characterized in that a 0.900 to 0.980.
The present invention is a two-component developer comprising any one of the toners described above and a carrier composed of magnetic particles.

The present invention relates to an electrostatic image carrier that forms a latent image, a charging unit that uniformly charges the surface of the image carrier, and exposure that writes the latent image by exposing the charged image carrier surface based on image data. Means, a developing means for supplying toner to the latent image formed on the surface of the image carrier and making it visible, a cleaning means for cleaning the surface of the image carrier, and a charge removing means for eliminating the charge on the surface of the image carrier When, with a contact transfer means for transferring to a recording medium after transferring the visible image on the image carrier surface directly or to an intermediate transfer member, and a heat fixing means for fixing the toner image on the recording medium, the developing means and the An image forming apparatus using any one of the electrostatic image developing toners.
The present invention, the charging means is brought into contact with the charging member to the electrostatic image bearing member, are images forming device you being a charging device which performs charging by applying a voltage to the charging member .
The present invention, the electrostatic image bearing member, is images forming device you characterized in that an amorphous silicon electrostatic image bearing member.
In the present invention, the heating and fixing unit includes a heating body provided with a heating element, a film in contact with the heating body, and a pressure member in pressure contact with the heating body through the film. is images forming device you wherein the member is a fixing device is passed through heat fixing an unfixed recording material on which an image was formed a between.
The present invention relates to a process cartridge which integrally supports an electrostatic image bearing member photoreceptor and at least one unit selected from a charging unit, a developing unit, and a cleaning unit and is detachable from an image forming apparatus. The developing means holds a toner, and the toner is at least one of the electrostatic image developing toners.
The present invention is an image forming apparatus characterized by comprising said process cartridge.

According to the present invention, it is possible to provide a toner for developing an electrostatic image that is compatible with a low-temperature fixing system, has good offset resistance, and does not contaminate the fixing device and the image.
Further, even if a process cartridge using electrostatic charge image developing toner is mounted, the same excellent effect can be obtained.
Also, a charging device with reduced generation of ozone, a photoconductor that has high surface hardness, high sensitivity to long wavelength light such as a semiconductor laser (770 to 800 nm), etc., and that is hardly deteriorated by repeated use, and It is possible to provide an image forming apparatus using a fixing device that is efficient and can shorten the rise time.

The best mode for carrying out the present invention will be described below with reference to the drawings. The following description is an example of the best mode of the present invention, and it is easy for those skilled in the art to make other embodiments within the scope of the claims by making changes and modifications within the scope of the claims. However, this does not limit the scope of the claims.
[Organic solvent phase]
<Organic solvent>
The materials used for producing the toner of the present invention will be described. In the present invention, the organic solvent is not particularly limited as long as it is a solvent capable of dissolving and / or dispersing the toner composition. As a preferable thing, it is preferable from the point that removal is easy that the boiling point of a solvent is less than 150 degreeC. Examples of the solvent include toluene, xylene, benzene, carbon tetrachloride, methylene chloride, 1,2-dichloroethane, 1,1,2-trichloroethane, trichloroethylene, chloroform, monochlorobenzene, methyl acetate, ethyl acetate, methyl ethyl ketone, acetone, Tetrahydrofuran or the like can be used alone or in combination of two or more. Of these, methyl acetate and ethyl acetate are preferred because they are particularly volatile to toner. The amount of the solvent used relative to 100 parts of the toner solid component is usually 40 to 300 parts, preferably 60 to 140 parts, and more preferably 80 to 120 parts.

<Functional group-containing polyester resin>
In the present invention, a polyester prepolymer having an isocyanate group can be used as the modified polyester resin. Examples of the polyester prepolymer (A) having an isocyanate group include a product obtained by further reacting a polyester having an active hydrogen group with a polyisocyanate (3), which is a polycondensate of polyol (1) and polycarboxylic acid (2). Can be mentioned. Examples of the active hydrogen group possessed by the polyester include hydroxyl groups (alcoholic hydroxyl groups and phenolic hydroxyl groups), amino groups, carboxyl groups, mercapto groups, and the like. Among these, alcoholic hydroxyl groups are preferred.
Examples of the polyol (1) include a diol (1-1) and a tri- or higher valent polyol (1-2). (1-1) alone or (1-1) and a small amount of (1-2) Mixtures are preferred. Diol (1-1) includes alkylene glycol (ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,6-hexanediol, etc.); alkylene ether glycol (diethylene glycol) , Triethylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol, etc.); alicyclic diols (1,4-cyclohexanedimethanol, hydrogenated bisphenol A, etc.); bisphenols (bisphenol A, bisphenol) F, bisphenol S, etc.); alkylene oxide (ethylene oxide, propylene oxide, butylene oxide, etc.) adduct of the alicyclic diol; bisphenol And alkylene oxide (ethylene oxide, propylene oxide, butylene oxide, etc.) adducts. Among them, preferred are alkylene glycols having 2 to 12 carbon atoms and alkylene oxide adducts of bisphenols, and particularly preferred are alkylene oxide adducts of bisphenols and alkylene glycols having 2 to 12 carbon atoms. It is a combined use.

The trihydric or higher polyol (1-2) includes 3 to 8 or higher polyhydric aliphatic alcohols (glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, sorbitol, etc.); trihydric or higher phenols (Trisphenol PA, phenol novolak, cresol novolak, etc.); and alkylene oxide adducts of the above trivalent or higher polyphenols.
Examples of the polycarboxylic acid (2) include dicarboxylic acid (2-1) and trivalent or higher polycarboxylic acid (2-2). (2-1) alone and (2-1) with a small amount of ( The mixture of 2-2) is preferred. Dicarboxylic acid (2-1) includes alkylene dicarboxylic acid (succinic acid, adipic acid, sebacic acid, etc.); alkenylene dicarboxylic acid (maleic acid, fumaric acid, etc.); aromatic dicarboxylic acid (phthalic acid, isophthalic acid, terephthalic acid) And naphthalenedicarboxylic acid). Of these, preferred are alkenylene dicarboxylic acids having 4 to 20 carbon atoms and aromatic dicarboxylic acids having 8 to 20 carbon atoms.
Examples of the trivalent or higher polycarboxylic acid (2-2) include aromatic polycarboxylic acids having 9 to 20 carbon atoms (trimellitic acid, pyromellitic acid, and the like). In addition, as polycarboxylic acid (2), you may make it react with polyol (1) using the acid anhydride or lower alkyl ester (methyl ester, ethyl ester, isopropyl ester, etc.) of the above-mentioned thing.
In order to adjust the polyester having an alcoholic hydroxyl group at the terminal by a polycondensation reaction, the ratio of the polyol (1) and the polycarboxylic acid (2) is equivalent to the equivalent ratio [OH] / [hydroxyl group [OH] and carboxyl group [COOH]. COOH] is usually 2/1 to 1/1, preferably 1.5 / 1 to 1/1, and more preferably 1.3 / 1 to 1.02 / 1.

Examples of the polyisocyanate (3) used for preparing the polyester prepolymer by reacting with the alcoholic hydroxyl group of the polyester include aliphatic polyisocyanates (tetramethylene diisocyanate, hexamethylene diisocyanate, 2,6-diisocyanatomethyl carbonate). Proate, etc.); alicyclic polyisocyanates (isophorone diisocyanate, cyclohexylmethane diisocyanate, etc.); aromatic diisocyanates (tolylene diisocyanate, diphenylmethane diisocyanate, etc.); Xylylene diisocyanate); isocyanurates; the polyisocyanate blocked with a phenol derivative, oxime, caprolactam, etc .; and These two or more types can be used in combination.
The use ratio of the polyisocyanate is generally 5/1 to 1/1, preferably 4/1 to 1 as an equivalent ratio [NCO] / [OH] of the isocyanate group [NCO] and the hydroxyl group [OH] of the polyester having a hydroxyl group. 1.2 / 1, more preferably 2.5 / 1 to 1.5 / 1. When [NCO] / [OH] exceeds 5, low-temperature fixability deteriorates. If the molar ratio of [NCO] is less than 1, the urea content in the modified polyester will be low, and the hot offset resistance will deteriorate.
The number of isocyanate groups contained per molecule in the prepolymer (A) having an isocyanate group is usually 1 or more, preferably 1.5 to 3 on average, more preferably 1.8 to 2.5 on average. It is. If it is less than 1 per molecule, the molecular weight of the modified polyester after crosslinking and / or elongation becomes low, and the hot offset resistance deteriorates.

<Combination of non-reactive low molecular weight polyester>
In the present invention, it is important not only to use the modified polyester (A) alone, but also to contain an unmodified polyester (C) that is not modified with the (A) as a toner binder component. By using (C) in combination, the low-temperature fixability and the glossiness when used in a full-color apparatus are improved. Examples of (C) include the same polycondensates of polyol (1) and polycarboxylic acid (2) as in the polyester component (A), and preferred ones are also the same as (C). (C) is not limited to unmodified polyester, but may be modified with a chemical bond other than a urea bond, and may be modified with, for example, a urethane bond. It is preferable that (A) and (C) are at least partially compatible with each other in terms of low-temperature fixability and hot offset resistance. Accordingly, the polyester component (A) and (C) preferably have similar compositions. When (A) is contained, the weight ratio of (A) to (C) is usually 5/95 to 75/25, preferably 10/90 to 25/75, more preferably 12/88 to 25/75, Especially preferably, it is 12 / 88-22 / 78. If the weight ratio of (A) is less than 5%, the hot offset resistance deteriorates, and it is disadvantageous in terms of both heat-resistant storage stability and low-temperature fixability.
The peak molecular weight measured by GPC (gel permeation chromatography) of the polyester (C) is usually 1000 to 30000, preferably 1500 to 10000, more preferably 2000 to 8000. If it is less than 1000, heat-resistant storage stability will deteriorate, and if it exceeds 10,000, low-temperature fixability will deteriorate. The hydroxyl value of (C) is preferably 5 or more, more preferably 10 to 120, and particularly preferably 20 to 80. If it is less than 5, it is disadvantageous in terms of both heat-resistant storage stability and low-temperature fixability. The acid value of (C) is usually 0.5 to 40, preferably 5 to 35. If the acid value is too high, it tends to be negatively charged, which is not preferable. Those exceeding this range are susceptible to environmental influences under high temperature and high humidity and low temperature and low humidity environments, and are liable to cause image deterioration.

[Active hydrogen-containing compounds]
As will be described later, the above-mentioned polyester prepolymer (A) having an isocyanate group is made to have a higher molecular weight by being subjected to elongation and / or crosslinking reaction with an active hydrogen compound.
In the present invention, amines can be used as a crosslinking agent and / or an extender. As amines (B), diamine (B1), trivalent or higher polyamine (B2), aminoalcohol (B3), aminomercaptan (B4), amino acid (B5), and amino acids B1-B5 blocked (B6) etc. are mentioned. Examples of the diamine (B1) include aromatic diamines (phenylenediamine, diethyltoluenediamine, 4,4′diaminodiphenylmethane, etc.); alicyclic diamines (4,4′-diamino-3,3′dimethyldicyclohexylmethane, diaminecyclohexane, Isophorone diamine etc.); and aliphatic diamines (ethylene diamine, tetramethylene diamine, hexamethylene diamine etc.) and the like. Examples of the trivalent or higher polyamine (B2) include diethylenetriamine and triethylenetetramine. Examples of amino alcohol (B3) include ethanolamine and hydroxyethylaniline. Examples of amino mercaptan (B4) include aminoethyl mercaptan and aminopropyl mercaptan. Examples of the amino acid (B5) include aminopropionic acid and aminocaproic acid. Examples of the B1 to B5 amino group blocked (B6) include ketimine compounds and oxazoline compounds obtained from the B1 to B5 amines and ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.). Among these amines (B), preferred are B1 and a mixture of B1 and a small amount of B2.
Furthermore, if necessary, the molecular weight of the modified polyester after completion of the reaction can be adjusted by using a terminator for crosslinking and / or elongation. Examples of the terminator include monoamines (diethylamine, dibutylamine, butylamine, laurylamine, etc.), and those blocked (ketimine compounds).

[Tertiary amine compound]
In the present invention, a tertiary amine compound is used as a catalyst for crosslinking and / or elongation. Any tertiary amine compound can be used and is not particularly limited. Examples of the tertiary amine compound include amines, amino alcohols, amino mercaptans, and amidines. Examples of amines include aromatic amines (such as triphenylamine and triallylamine), alicyclic amines (such as N-methylpiperidine); and aliphatic amines (such as triethylamine and trimethylamine). Examples of amino alcohols include triethanolamine and dihydroxyethylaniline. Examples of amino mercaptans include triethanethiolamine and trimethanethiolamine. Examples of amidine include DBU (1,8-diaza-bicyclo [5.4.0] undecene-7) and DBN (1,5-diaza-bicyclo [4.3.0] nonene-5). It is done. Among these tertiary amine compounds, the compound of the structural formula (I) is more preferable.

  The ratio of amines (B) is the equivalent ratio [NCO] / [NHx] of isocyanate groups [NCO] in the prepolymer (A) having isocyanate groups and amino groups [NHx] in amines (B). The ratio is usually 1/2 to 2/1, preferably 1.5 / 1 to 1 / 1.5, more preferably 1.2 / 1 to 1 / 1.2. When [NCO] / [NHx] is greater than 2 or less than 1/2, the molecular weight of the urea-modified polyester (i) becomes low, and the hot offset resistance deteriorates.

<Features of toner binder>
In the present invention, as described above, the polyester prepolymer (A) is characterized by using, as a toner binder, a urea-modified polyester resin obtained by a reaction between an amine (B) and non-reactive polyester, etc. Other components (including the resin used for the colorant master batch) are also used. In the present invention, the glass transition point (Tg) of the toner binder is usually 40 to 70 ° C., preferably 45 to 55 ° C. If it is less than 40 ° C., the heat-resistant storage stability of the toner deteriorates, and if it exceeds 70 ° C., the low-temperature fixability becomes insufficient. Due to the coexistence of the crosslinked and / or elongated polyester resin, the toner for developing an electrostatic charge image of the present invention exhibits good storage stability even when the glass transition point is low, as compared with known polyester-based toners. As the storage elastic modulus of the toner, the temperature (TG ′) at which the measurement frequency is 20 Hz becomes 1000 Pa is usually 100 ° C. or higher, preferably 110 to 200 ° C. If it is less than 100 ° C., the resistance to hot offset deteriorates. As the viscosity of the toner, the temperature (Tη) at 100 Pa · s at a measurement frequency of 20 Hz is usually 180 ° C. or lower, preferably 90 to 160 ° C. If it exceeds 180 ° C., the low-temperature fixability deteriorates. That is, TG ′ is preferably higher than Tη from the viewpoint of achieving both low temperature fixability and hot offset resistance. In other words, the difference between TG ′ and Tη (TG′−Tη) is preferably 0 ° C. or higher. More preferably, it is 10 degreeC or more, Most preferably, it is 20 degreeC or more. The upper limit of the difference is not particularly limited. Further, from the viewpoint of achieving both heat-resistant storage stability and low-temperature fixability, the difference between Tη and Tg is preferably 0 to 100 ° C. More preferably, it is 10-90 degreeC, Most preferably, it is 20-80 degreeC.

[Aqueous medium phase]
<Aqueous medium>
In the present invention, the aqueous medium in which the resin fine particles described later are dispersed to form an aqueous medium phase may be water alone, or a solvent miscible with water may be used in combination. Examples of miscible solvents include alcohols (methanol, isopropanol, ethylene glycol, etc.), dimethylformamide, tetrahydrofuran, cellosolves, and lower ketones (acetone, methyl ethyl ketone, etc.). These can be used singly or in combination of two or more.

<Resin fine particles>
The resin fine particles in the toner of the present invention are added in the production process in order to control the toner shape (circularity, particle size distribution, etc.) described later. As will be described later, the fine particles are considered to be bonded to the surface portion when an organic solvent phase and an active hydrogen-containing compound (amines) are dispersed in an aqueous medium to form organic dispersed particles. Thus, it is considered that the toner base particles obtained are unevenly distributed mainly on the surface portion as in the case of the external additive described later. In the present invention, it is necessary and important that the amount of resin fine particles contained in the obtained toner particles after the external additive treatment is 0.5 to 5.0 wt%. When the content is less than 0.5 wt%, the storability of the toner deteriorates, blocking occurs during storage and in the developing machine, and when the remaining amount is 5.0 wt% or more, the resin fine particles are not present. The exudation of the wax is obstructed, the effect of releasing the wax is not obtained, and the occurrence of offset is observed. Further, it is important that the glass transition point (Tg) of the resin fine particles is 40 to 100 ° C. and the weight average molecular weight is 9000 to 200,000. If the Tg of the resin fine particles is less than 40 ° C. and / or the weight average molecular weight is less than 9,000, the storage stability of the toner deteriorates, and blocking occurs during storage and in the developing machine. Is 80 ° C. or higher and / or the weight average molecular weight is 200,000 or higher, the resin fine particles inhibit the adhesiveness to the fixing paper, and an increase in the minimum fixing temperature is observed.

The residual rate of the resin fine particles can be measured by analyzing a substance caused by the resin fine particles, not by the toner particles, using a pyrolysis gas chromatograph mass spectrometer, and calculating from the peak area.
The detector is preferably a mass spectrometer, but is not particularly limited. The dispersion / blending amount of the resin fine particles in the aqueous medium may be set so as to satisfy the conditions related to the content, but is usually in the range of about 0.5 to 10% by weight.
The resin fine particles may be any resin as long as it can form an aqueous dispersion, and may be a thermoplastic resin or a thermosetting resin. For example, vinyl resin, polyurethane resin, epoxy resin, polyester resin, polyamide resin, polyimide Examples thereof include resins, silicon-based resins, phenol resins, melamine resins, urea resins, aniline resins, ionomer resins, and polycarbonate resins. As the resin fine particles, two or more of the above resins may be used in combination. Of these, vinyl resins, polyurethane resins, epoxy resins, polyester resins, and combinations thereof are preferred because an aqueous dispersion of fine spherical resin particles is easily obtained.
The vinyl resin is a polymer obtained by homopolymerization or copolymerization of a vinyl monomer, such as a styrene- (meth) acrylate resin, a styrene-butadiene copolymer, a (meth) acrylic acid-acrylate polymer, Examples include styrene-acrylonitrile copolymers, styrene-maleic anhydride copolymers, styrene- (meth) acrylic acid copolymers, and the like.

[Other ingredients]
<Colorant>
As the coloring agent of the present invention, all known dyes and pigments can be used. For example, carbon black, nigrosine dye, iron black, naphthol yellow S, Hansa yellow (10G, 5G, G), cadmium yellow, yellow iron oxide , Ocher, yellow lead, titanium yellow, polyazo yellow, oil yellow, Hansa Yellow (GR, A, RN, R), Pigment Yellow L, Benzidine Yellow (G, GR), Permanent Yellow (NCG), Vulcan Fast Yellow ( 5G, R), Tartrazine Lake, Quinoline Yellow Lake, Anthrazan Yellow BGL, Isoindolinone Yellow, Bengala, Red Dan, Lead Zhu, Cadmium Red, Cadmium Mercury Red, Antimon Zhu, Permanent Red 4R, Para Red , Fais red, parachlorol Nitroaniline Red, Resol Fast Scarlet G, Brilliant Fast Scarlet, Brilliant Carmine B, Permanent Red (F2R, F4R, FRL, FRLL, F4RH), Fast Scarlet VD, Belkan Fast Rubin B, Brilliant Scarlet G, Resol Rubin GX, Permanent Red F5R, Brilliant Carmine 6B, Pigment Scarlet 3B, Bordeaux 5B, Tolujing Maroon, Permanent Bordeaux F2K, Helio Bordeaux BL, Bordeaux 10B, Bon Maroon Light, Bon Maroon Medium, Eosin Lake, Rhodamine Lake B, Rhodamine Lake Y, Alizarin Lake , Thioindigo red B, thioindigo maroon, oil red, quinacridone red, pyrazolone , Polyazo red, chrome vermillion, benzidine orange, perinone orange, oil orange, cobalt blue, cerulean blue, alkali blue rake, peacock blue rake, Victoria blue rake, metal free phthalocyanine blue, phthalocyanine blue, fast sky blue, in Dunslen Blue (RS, BC), Indigo, Ultramarine Blue, Bitumen, Anthraquinone Blue, Fast Violet B, Methyl Violet Lake, Cobalt Purple, Manganese Purple, Dioxane Violet, Anthraquinone Violet, Chrome Green, Zinc Green, Chrome Oxide, Pyridian, Emerald Green, Pigment Green B, Naphthol Green B, Green Gold, Acid Green Lake, Malachite Green Lake Phthalocyanine green, anthraquinone green, titanium oxide, zinc white, litbon and mixtures thereof can be used. The content of the colorant is usually 1 to 15% by weight, preferably 3 to 10% by weight as the content in the toner base of the present invention.

The colorant used in the present invention can also be used as a master batch combined with a resin. Examples of the binder resin kneaded together with the production of the master batch or the master batch include, for example, the above-mentioned urea-modified polyester resin and non-reactive polyester resin, as well as the weight of styrene such as polystyrene, poly p-chlorostyrene, and polyvinyltoluene, and their substituted products. Styrene-p-chlorostyrene copolymer, styrene-propylene copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer Polymer, styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer, styrene- α-Chlormeta Methyl acrylate copolymer, styrene-acrylonitrile copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile-indene copolymer, styrene-maleic acid Styrene copolymers such as copolymers and styrene-maleic acid ester copolymers; polymethyl methacrylate, polybutyl methacrylate, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, polyester, epoxy resin, epoxy polyol resin, polyurethane , Polyamide, polyvinyl butyral, polyacrylic acid resin, rosin, modified rosin, terpene resin, aliphatic or alicyclic hydrocarbon resin, aromatic petroleum resin, chlorinated paraffin, paraffin wax, etc. Or it can be used in combination.
This master batch can be obtained by mixing and kneading a resin for a master batch and a colorant under a high shear force to obtain a master batch. At this time, an organic solvent can be used to enhance the interaction between the colorant and the resin. In addition, a so-called flushing method, which is a wet cake of a coloring agent, is a method of mixing and kneading an aqueous paste containing water of a coloring agent together with a resin and an organic solvent, transferring the coloring agent to the resin side, and removing moisture and organic solvent components. Can be used as it is, so that it is not necessary to dry and is preferably used. For mixing and kneading, a high shear dispersion device such as a three-roll mill is preferably used. The colorant or masterbatch can be dissolved or dispersed in the organic solvent phase, but is not limited thereto.

<Release agent>
Further, a wax may be contained together with the toner binder and the colorant. Known waxes can be used as the wax of the present invention, and examples include polyolefin wax (polyethylene wax, polypropylene wax, etc.); long chain hydrocarbon (paraffin wax, sazol wax, etc.); carbonyl group-containing wax. Of these, carbonyl group-containing waxes are preferred. Carbonyl group-containing waxes include polyalkanoic acid esters (carnauba wax, montan wax, trimethylolpropane tribehenate, pentaerythritol tetrabehenate, pentaerythritol diacetate dibehenate, glycerin tribehenate, 1,18. -Octadecanediol distearate, etc.); polyalkanol esters (tristearyl trimellitic acid, distearyl maleate, etc.); polyalkanoic acid amides (ethylene diamine dibehenyl amide, etc.); polyalkylamides (trimellitic acid tristearyl amide, etc.) And dialkyl ketones (such as distearyl ketone). Among these carbonyl group-containing waxes, polyalkanoic acid esters are preferred. The melting point of the wax of the present invention is usually 40 to 160 ° C, preferably 50 to 120 ° C, more preferably 60 to 90 ° C. A wax having a melting point of less than 40 ° C. has an adverse effect on heat-resistant storage stability, and a wax having a melting point of more than 160 ° C. tends to cause a cold offset when fixing at a low temperature. Further, the melt viscosity of the wax is preferably 5 to 1000 cps, more preferably 10 to 100 cps as a measured value at a temperature 20 ° C. higher than the melting point. Waxes exceeding 1000 cps have poor effects for improving hot offset resistance and low-temperature fixability. The amount of the wax (release agent) used is usually 0 to 40% by weight, preferably 3 to 30% by weight as the content in the toner base. Further, the wax (release agent) can be dissolved or dispersed in the organic solvent phase, but is not limited thereto.

<Charge control agent>
The toner of the present invention may contain a charge control agent as necessary. All known charge control agents can be used, such as nigrosine dyes, triphenylmethane dyes, chromium-containing metal complex dyes, molybdate chelate pigments, rhodamine dyes, alkoxy amines, quaternary ammonium salts (fluorine-modified). Quaternary ammonium salts), alkylamides, phosphorus simple substances or compounds, tungsten simple substances or compounds, fluorine-based activators, salicylic acid metal salts, and metal salts of salicylic acid derivatives. Specifically, Nitronine-based dye Bontron 03, quaternary ammonium salt Bontron P-51, metal-containing azo dye Bontron S-34, oxynaphthoic acid metal complex E-82, salicylic acid metal complex E- 84, E-89 of phenol-based condensate (above, manufactured by Orient Chemical Industries), TP-302, TP-415 of quaternary ammonium salt molybdenum complex (above, manufactured by Hodogaya Chemical Co., Ltd.), quaternary ammonium Copy charge PSY VP2038 of salt, Copyble-PR of triphenylmethane derivative, Copy charge of quaternary ammonium salt NEG VP2036, Copy charge NX VP434 (manufactured by Hoechst), LRA-901, LR-147 which is a boron complex (Nippon Carlit), copper phthalocyanine, perylene, quinacridone Azo pigments, sulfonate group, a carboxyl group include compounds of polymers having a functional group such as quaternary ammonium salts.
In the present invention, the amount of charge control agent used is determined uniquely by the type of binder resin, the presence or absence of additives used as necessary, and the toner production method including the dispersion method, and is uniquely limited. However, it is preferably used in the range of 0.1 to 10 parts by weight with respect to 100 parts by weight of the binder resin. The range of 0.2 to 5 parts by weight is preferable. When the amount exceeds 10 parts by weight, the chargeability of the toner is too high, the effect of the main charge control agent is reduced, the electrostatic attractive force with the developing roller is increased, the flowability of the developer is reduced, and the image density is reduced. Incurs a decline. These charge control agents can be dissolved and dispersed after being melt-kneaded with a masterbatch or resin, and of course, they may be added directly when dissolved and dispersed in an organic solvent. It is preferable to make it.

[Preparation of toner particles]
The dry toner of the present invention can be produced by the following method, but is not limited thereto.
<Toner production method in aqueous medium>
The aqueous phase used in the present invention is used by adding resin fine particles in advance. The water used for the aqueous phase may be water alone, or a solvent miscible with water may be used in combination. Examples of the miscible solvent include alcohol (methanol, isopropanol, ethylene glycol, etc.), dimethylformamide, tetrahydrofuran, cellosolves (methylcellosolve, etc.), lower ketones (acetone, methyl ethyl ketone, etc.) and the like.

<Dispersion and reaction of organic solvent phase>
As described above, the toner particles are obtained by dispersing the organic solvent phase containing the polyester prepolymer (A) in the aqueous medium phase together with the amines (B) and the tertiary amine, It is formed through a step of forming a urea-modified polyester by crosslinking reaction. As a method for stably forming a dispersion comprising a polyester prepolymer (A) in an aqueous phase, a composition of a toner raw material comprising a polyester prepolymer (A) dissolved or dispersed in an organic solvent in an aqueous phase is added. And a method of dispersing by shearing force. Polyester prepolymer (A) dissolved or dispersed in an organic solvent and other toner composition (hereinafter referred to as toner raw material), colorant masterbatch, release agent, charge control agent, unmodified The polyester resin or the like may be mixed when forming the dispersion in the aqueous phase, but after the toner raw material is mixed in advance and dissolved or dispersed in an organic solvent, the mixture is added to the aqueous phase and dispersed. Is more preferable. In the present invention, other toner raw materials such as a colorant, a release agent, and a charge control agent do not necessarily have to be mixed when forming particles in the aqueous phase. It may be added. For example, after forming particles containing no colorant, the colorant can be added by a known dyeing method.

The dispersion method is not particularly limited, and known equipment such as a low-speed shear method, a high-speed shear method, a friction method, a high-pressure jet method, and an ultrasonic wave can be applied. In order to make the particle size of the dispersion 2 to 20 μm, a high-speed shearing type is preferable. When a high-speed shearing disperser is used, the number of rotations is not particularly limited, but is usually 1000 to 30000 rpm, preferably 5000 to 20000 rpm. The dispersion time is not particularly limited, but in the case of a batch method, it is usually 0.1 to 5 minutes. The temperature during dispersion is usually 0 to 150 ° C. (under pressure), preferably 40 to 98 ° C. Higher temperatures are preferred in that the dispersion of the polyester prepolymer (A) has a low viscosity and is easy to disperse.
The usage-amount of the aqueous medium with respect to 100 parts of solid components contained in the organic solvent phase of a polyester prepolymer (A) is 50-2000 weight part normally, Preferably it is 100-1000 weight part. If the amount is less than 50 parts by weight, the dispersion state of the toner composition is poor, and toner particles having a predetermined particle diameter cannot be obtained. If it exceeds 20000 parts by weight, it is not economical. Moreover, a dispersing agent can also be used as needed. It is preferable to use a dispersant because the particle size distribution becomes sharp and the dispersion is stable.
As a dispersant for emulsifying and dispersing the organic solvent phase containing the polyester prepolymer (A) and the like, alkylbenzene sulfonates, α-olefin sulfonates, anionic surfactants such as phosphate esters, alkylamine salts, Amino alcohol fatty acid derivatives, polyamine fatty acid derivatives, amine salt types such as imidazoline, and quaternary alkyltrimethylammonium salts, dialkyldimethylammonium salts, alkyldimethylbenzylammonium salts, pyridinium salts, alkylisoquinolinium salts, benzethonium chloride, etc. Nonionic surfactants such as ammonium salt type cationic surfactants, fatty acid amide derivatives, polyhydric alcohol derivatives, such as alanine, dodecyldi (aminoethyl) glycine, di (octylaminoethyl) glycine and N-alkyl -N, amphoteric surfactants such as N- dimethyl ammonium betaine.

Further, by using a surfactant having a fluoroalkyl group, the effect can be obtained in a very small amount. Preferred anionic surfactants having a fluoroalkyl group include fluoroalkylcarboxylic acids having 2 to 10 carbon atoms and metal salts thereof, disodium perfluorooctanesulfonyl glutamate, 3- [omega-fluoroalkyl (C6 to C11). ) Oxy] -1-alkyl (C3-C4) sodium sulfonate, 3- [omega-fluoroalkanoyl (C6-C8) -N-ethylamino] -1-propanesulfonic acid sodium, fluoroalkyl (C11-C20) carvone Acids and metal salts, perfluoroalkylcarboxylic acids (C7 to C13) and metal salts thereof, perfluoroalkyl (C4 to C12) sulfonic acids and metal salts thereof, perfluorooctanesulfonic acid diethanolamide, N-propyl-N- ( 2-hydroxyethyl Perfluorooctanesulfonamide, perfluoroalkyl (C6-C10) sulfonamidopropyltrimethylammonium salt, perfluoroalkyl (C6-C10) -N-ethylsulfonylglycine salt, monoperfluoroalkyl (C6-C16) ethyl phosphate, etc. Is mentioned.
Product names include Surflon S-111, S-112, S-113 (Asahi Glass Co., Ltd.), Florard FC-93, FC-95, FC-98, FC-129 (Sumitomo 3M Co., Ltd.), Unidyne DS-101. DS-102 (manufactured by Taikin Kogyo Co., Ltd.), Megafac F-110, F-120, F-113, F-191, F-812, F-833 (Dainippon Ink Co., Ltd.), Xtop EF-102 , 103, 104, 105, 112, 123A, 123B, 306A, 501, 201, 204 (manufactured by Tochem Products), and Fgentent F-100, F150 (manufactured by Neos).

In addition, as the cationic surfactant, an aliphatic quaternary ammonium salt such as an aliphatic primary, secondary or secondary amic acid, perfluoroalkyl (C 6 -C 10) sulfonamidopropyltrimethylammonium salt that has a right fluoroalkyl group, Benzalkonium salts, benzethonium chloride, pyridinium salts, imidazolinium salts, trade names include Surflon S-121 (manufactured by Asahi Glass), Florard FC-135 (manufactured by Sumitomo 3M), Unidyne DS-202 (manufactured by Daikin Industries, Ltd.) ), Megafuck F-150, F-824 (Dainippon Ink Co., Ltd.), Xtop EF-132 (Tochem Products Co., Ltd.), Footgent F-300 (Neos Co., Ltd.), and the like.
Moreover, tricalcium phosphate, calcium carbonate, titanium oxide, colloidal silica, hydroxyapatite, etc. can be used as an inorganic compound dispersant which is hardly soluble in water.

  Further, the dispersed droplets may be stabilized by a polymer protective colloid. For example, acrylic acid, methacrylic acid, α-cyanoacrylic acid, α-cyanomethacrylic acid, itaconic acid, crotonic acid, fumaric acid, maleic acid or maleic anhydride and other (meth) acrylic monomers containing hydroxyl groups Bodies such as β-hydroxyethyl acrylate, β-hydroxyethyl methacrylate, β-hydroxypropyl acrylate, β-hydroxypropyl methacrylate, γ-hydroxypropyl acrylate, γ-hydroxypropyl methacrylate, 3-acrylate Chloro-2-hydroxypropyl, 3-chloro-2-hydroxypropyl methacrylate, diethylene glycol monoacrylate, diethylene glycol monomethacrylate, glycerol monoacrylate, glycerol monomethacrylate, N -Methylol acrylamide, N-methylol methacrylamide, etc., vinyl alcohol or ethers with vinyl alcohol, such as vinyl methyl ether, vinyl ethyl ether, vinyl propyl ether, or esters of compounds containing vinyl alcohol and carboxyl groups For example, pinyl acetate, pinyl propionate, vinyl butyrate, acrylamide, methacrylamide, diacetone acrylamide or their methylol compounds, acid chlorides such as acrylic acid chloride, methacrylic acid chloride, pinylviridine, vinylpyrrolidone, vinylimidazole, ethyleneimine Homopolymers or copolymers such as those having a nitrogen atom or its heterocyclic ring, polyoxyethylene, polyoxypropylene, Oxyethylene alkylamine, polyoxypropylene alkylamine, polyoxyethylene alkylamide, polyoxypropylene alkylamide, polyoxyethylene nonyl phenyl ether, polyoxyethylene lauryl phenyl ether, polyoxyethylene stearyl phenyl ester, polyoxyethylene nonylphenyl Polyoxyethylenes such as esters, celluloses such as methyl cellulose, hydroxyethyl cellulose, and hydroxypropyl cellulose can be used.

In addition, when an acid such as calcium phosphate salt or an alkali-soluble substance is used as the dispersion stabilizer, the calcium phosphate salt is removed from the fine particles by a method such as dissolving the calcium phosphate salt with an acid such as hydrochloric acid and washing with water. To do. It can also be removed by operations such as enzymatic degradation.
When a dispersant is used, the dispersant can remain on the surface of the toner particles. However, it is preferable from the charged surface of the toner that the dispersant is washed and removed after the elongation and / or crosslinking reaction.
The elongation and / or cross-linking reaction time is selected depending on the reactivity of the isocyanate group structure of the prepolymer (A) and the amines (B), but is usually 10 minutes to 40 hours, preferably 2 to 24 hours. is there. The reaction temperature is generally 0 to 150 ° C, preferably 40 to 98 ° C. Moreover, a well-known catalyst can be used as needed. Specific examples include dibutyltin laurate and dioctyltin laurate.
In order to remove the organic solvent from the obtained emulsified dispersion, a method can be employed in which the temperature of the entire system is gradually raised and the organic solvent in the droplets is completely evaporated and removed. Alternatively, it is also possible to spray the emulsified dispersion in a dry atmosphere to completely remove the water-insoluble organic solvent in the droplets to form toner fine particles, and to evaporate and remove the aqueous dispersant together. . As a dry atmosphere in which the emulsified dispersion is sprayed, a gas obtained by heating air, nitrogen, carbon dioxide gas, combustion gas, or the like, particularly various air streams heated to a temperature equal to or higher than the boiling point of the highest boiling solvent used are generally used. Sufficient quality can be obtained with a short treatment such as spray dryer, belt dryer or rotary kiln.

When the particle size distribution at the time of emulsification dispersion is wide and washing and drying processes are performed while maintaining the particle size distribution, the particle size distribution can be adjusted by classifying into a desired particle size distribution.
In the classification operation, the fine particle portion can be removed in the liquid by a cyclone, a decanter, centrifugation, or the like. Of course, the classification operation may be performed after obtaining the powder as a powder after drying. The unnecessary fine particles or coarse particles obtained can be returned to the kneading step and used for the formation of particles. At that time, fine particles or coarse particles may be wet.
The dispersant used is preferably removed from the obtained dispersion as much as possible, but it is preferable to carry out it simultaneously with the classification operation described above.
Mixing or giving mechanical impact force to the powder mixture after drying with different types of particles such as release agent fine particles, charge control fine particles, fluidizing agent fine particles, and colorant fine particles By immobilizing and fusing on the surface, it is possible to prevent detachment of foreign particles from the surface of the resulting composite particle.
Specific means include a method of applying an impact force to the mixture by blades rotating at high speed, a method of injecting and accelerating the mixture in a high-speed air stream, and causing particles or composite particles to collide with an appropriate collision plate, etc. is there. As equipment, Ong mill (manufactured by Hosokawa Micron Co., Ltd.), I-type mill (manufactured by Nippon Pneumatic Co., Ltd.), modified with reduced pulverization air pressure, hybridization system (manufactured by Nara Machinery Co., Ltd.), Kryptron System (manufactured by Kawasaki Heavy Industries, Ltd.), automatic mortar, etc.

[Application of external additives]
As the external additive for assisting the fluidity, developability and chargeability of the colored particles obtained in the present invention, inorganic fine particles can be preferably used. The primary particle diameter of the inorganic fine particles is preferably 5 mμ to 2 μm, particularly preferably 5 mμ to 500 mμ. Moreover, it is preferable that the specific surface area by BET method is 20-500 m < ² > / g. The proportion of the inorganic fine particles used is preferably 0.01 to 5% by weight of the toner, and particularly preferably 0.01 to 2.0% by weight.
Specific examples of the inorganic fine particles include, for example, silica, alumina, titanium oxide, barium titanate, magnesium titanate, calcium titanate, strontium titanate, zinc oxide, tin oxide, quartz sand, clay, mica, wollastonite, diatomaceous earth. Examples include soil, chromium oxide, cerium oxide, pengala, antimony trioxide, magnesium oxide, zirconium oxide, barium sulfate, barium carbonate, calcium carbonate, silicon carbide, and silicon nitride.
Other polymer fine particles such as polystyrene obtained by soap-free emulsion polymerization, suspension polymerization and dispersion polymerization, methacrylic acid ester and acrylic acid ester copolymer, polycondensation system such as silicone, benzoguanamine and nylon, and thermosetting resin Examples include polymer particles.
Such a fluidizing agent can be surface-treated to increase hydrophobicity and prevent deterioration of flow characteristics and charging characteristics even under high humidity. For example, silane coupling agents, silylating agents, silane coupling agents having a fluoroalkyl group, organic titanate coupling agents, aluminum coupling agents, silicone oils, modified silicone oils and the like are preferable surface treatment agents. .
On the other hand, examples of the cleaning property improver for removing the developer after transfer remaining on the photosensitive member or the primary transfer medium include fatty acid metal salts such as zinc stearate, calcium stearate, and stearic acid, such as polymethyl methacrylate fine particles, polystyrene. Examples thereof include fine polymer particles produced by soap-free emulsion polymerization of fine particles and the like. The polymer fine particles preferably have a relatively narrow particle size distribution and a volume average particle size of 0.01 to 1 μm.

[Toner shape, etc.]
<Circularity and circularity distribution>
It is important for the toner in the present invention to have a specific shape and shape distribution, and with an irregularly shaped toner having an average circularity of less than 0.90 and far away from a sphere, satisfactory transferability and dust A high-quality image with no image cannot be obtained. As a method for measuring the shape, an optical detection band method is suitable in which a suspension containing particles is passed through an imaging unit detection band on a flat plate, and a particle image is optically detected and analyzed by a CCD camera. Toner having an average circularity of 0.980 to 0.900, which is a value obtained by dividing the perimeter of an equivalent circle having the same projected area obtained by this method by the perimeter of the actual particle, has high density with a reproducibility of an appropriate density. It was found to be effective in forming a clear image. More preferably, particles having an average circularity of 0.970 to 0.950 and a circularity of less than 0.94 are 15% or less. When the average circularity is 0.980 or more, in a system that employs blade cleaning or the like, a cleaning failure occurs on the photosensitive member or the transfer belt, causing stain on the image. For example, development / transfer with a low image area ratio results in a small amount of residual toner and poor cleaning does not become a problem. The image-formed toner may be generated as a transfer residual toner on the photosensitive member, and if accumulated, the image may be soiled. In addition, the charging roller that contacts and charges the photosensitive member is contaminated, and the original charging ability cannot be exhibited. This value was measured as an average circularity by a flow type particle image analyzer FPIA-2100 (manufactured by Toa Medical Electronics Co., Ltd.). A specific measurement method will be described later.

<Volume average particle diameter, number average particle diameter>
The toner of the present invention preferably has a volume average particle diameter (Dv) of 3 to 8 μm, more preferably 4 to 7 μm. The ratio (Dv / Dn) of the volume average particle diameter (Dv) to the number average particle diameter (Dn) is 1.25 or less, preferably 1.10 to 1.20. Here, the volume average particle diameter (Dv) is defined as Dv = [Σ (nD ³ ) / Σn] ^1/3 (where n is the number of particles and D is the particle diameter). In the present invention, by setting the value of (Dv / Dn) within the above range, it is excellent in all of heat resistant storage stability, low temperature fixability and hot offset resistance, and particularly when used in a full-color copying machine or the like. Excellent two-component developer, even with long-term toner balance, fluctuations in toner particle diameter in the developer are reduced, and even with long-term agitation in the developing device, it is stable and stable. Developability is obtained. Even when used as a one-component developer, even if the balance of the toner is performed, the fluctuation of the toner particle diameter is reduced, and the toner filming on the developing roller and the toner layer are made thin. The toner is not fused to a member such as a blade, and good and stable developability and an image can be obtained even in the long-term use (stirring) of the developing device.
In general, it is said that the smaller the particle size of the toner, the more advantageous it is to obtain a high-resolution and high-quality image, but it is disadvantageous for transferability and cleaning properties. is there. Further, when the volume average particle diameter is smaller than the range of the present invention, in the case of the two-component developer, the toner is fused to the surface of the carrier during a long period of stirring in the developing device, and the charging ability of the carrier is reduced, or the one-component development When used as an agent, toner filming on the developing roller and toner fusion to a member such as a blade for thinning the toner are likely to occur. These phenomena are the same for the toner having a fine powder content larger than the range of the present invention.

On the contrary, when the particle diameter of the toner is larger than the range of the present invention, it becomes difficult to obtain a high resolution and high quality image, and when the balance of the toner in the developer is performed, In many cases, the variation of the particle size becomes large. It was also clarified that the same applies when the volume average particle diameter / number average particle diameter (Dv / Dn) is too large. Furthermore, if the volume average particle diameter / number average particle diameter (Dv / Dn) is too small, there are preferable aspects in terms of stabilizing the behavior of the toner and uniforming the charge amount, but the toner becomes insufficiently charged. In some cases, it was also found that the cleaning property may be deteriorated.
The volume average particle diameter / number average particle diameter (Dv / Dn) is measured with a volume average particle diameter (Dv) measured with an aperture diameter of 100 μm using a particle size measuring device “Coulter Counter TAII” manufactured by Coulter Electronics. It is automatically measured by the value of the number average particle diameter (Dn).

[Two-component carrier]
When the toner of the present invention is used for a two-component developer, it may be used by mixing with a magnetic carrier. The carrier to toner content ratio in the developer is 1 to 10 weights of toner with respect to 100 parts by weight of carrier. Part is preferable, and the range of 3 to 9 parts by weight is more preferable. As the magnetic carrier, conventionally known ones such as iron powder, ferrite powder, magnetite powder, magnetic resin carrier having a particle diameter of about 20 to 200 μm can be used. Examples of the coating material include amino resins such as urea-formaldehyde resin, melamine resin, benzoguanamine resin, urea resin, polyamide resin, and epoxy resin. Polyvinyl and polyvinylidene resins such as acrylic resins, polymethyl methacrylate resins, polyacrylonitrile resins, polyvinyl acetate resins, polyvinyl alcohol resins, polyvinyl butyral resins, polystyrene resins and styrene acrylic copolymer resins, Halogenated olefin resins such as vinyl, polyester resins such as polyethylene terephthalate resin and polybutylene terephthalate resin, polycarbonate resins, polyethylene resins, polyvinyl fluoride resins, polyvinylidene fluoride resins, polytrifluoroethylene resins, polyhexafluoro Propylene resin, copolymer of vinylidene fluoride and acrylic monomer, copolymer of vinylidene fluoride and vinyl fluoride, tetrafluoroethylene and vinylidene fluoride And fluoro such as terpolymers of non-fluoride monomers including, and silicone resins. Moreover, you may contain electroconductive powder etc. in coating resin as needed. As the conductive powder, metal powder, carbon black, titanium oxide, tin oxide, zinc oxide or the like can be used. These conductive powders preferably have an average particle diameter of 1 μm or less. When the average particle diameter is larger than 1 μm, it becomes difficult to control electric resistance. The toner of the present invention can also be used as a one-component magnetic toner that does not use a carrier or a non-magnetic toner.

An image forming apparatus using the electrophotographic toner of the present invention or a two-component developer composed of the toner and a carrier will be described below.
FIG. 1 is a schematic configuration diagram of an image forming apparatus according to the present invention. Around a photosensitive drum (hereinafter referred to as a photosensitive member) 40 as an image carrier, a charging roller 60 as a charging device, an exposure device 21, a cleaning device 63 having a cleaning blade, a static elimination lamp 64 as a static elimination device, and development. An apparatus 61 and an intermediate transfer member 10 as an intermediate transfer member are provided. The intermediate transfer member 10 is suspended by a plurality of suspension rollers 14, 15 and 16, and is configured to run endlessly in the direction of an arrow by a driving unit such as a motor (not shown). A part of the suspension rollers 14, 15, 16 also serves as a transfer bias roller for supplying a transfer bias to the intermediate transfer member, and a predetermined transfer bias voltage is applied from a power source (not shown). A cleaning device 17 having a cleaning blade for the intermediate transfer member 10 is also provided. In addition, a transfer roller 22 is disposed as a transfer means for transferring the developed image onto the transfer paper P as a final transfer material, facing the intermediate transfer body 10, and the transfer roller 22 is supplied with a transfer bias by a power supply device (not shown). Is done. A corona charger 62 is provided around the intermediate transfer member 10 as charge applying means.
The developing device 61 includes a developing belt 41 as a developer carrier, a black (hereinafter referred to as “Bk”) developing unit 61K, a yellow (hereinafter referred to as “Y”) developing unit 61Y, The developing unit 61M and the cyan (hereinafter referred to as C) developing unit 61C are hereinafter referred to as magenta. The developing belt 41 is stretched between a plurality of belt rollers and is configured to run endlessly in a direction indicated by an arrow by a driving unit such as a motor (not shown). Move at almost the same speed.

The apparatus configuration of the image forming apparatus according to the present embodiment is not limited to the apparatus configuration illustrated in FIG. 1, but includes an apparatus configuration in which each color developing unit is provided around the photoconductor 40 as illustrated in FIG. 2. It may be.
Next, the operation of the image forming apparatus according to the present embodiment will be described. In FIG. 1, the photosensitive member 40 is uniformly charged by the charging device 60 while being rotated in the direction of the arrow, and then the reflected light from the document is imaged and projected onto the photosensitive member 40 by the optical system (not shown) by the exposure device 21. An electrostatic latent image is formed. This electrostatic latent image is developed by the developing device 61 to form a toner image as a visible image. The developer thin layer on the developing belt 41 is peeled off from the belt 41 in a thin layer state by contact with the photoconductor in the developing region, and moves to a portion where a latent image is formed on the photoconductor 40. The toner image developed by the developing device 40 is transferred to the surface of the intermediate transfer member 10 at the contact portion (primary transfer region) between the photosensitive member 40 and the intermediate transfer member 10 moving at a constant speed (primary transfer). Transcription). In the case of performing transfer in which three or four colors are superimposed, this process is repeated for each color, and a color image is formed on the intermediate transfer member 10.
The corona charger 62 for applying a charge to the superimposed toner image on the intermediate transfer member is arranged downstream of the contact facing portion between the photosensitive member 40 and the intermediate transfer member 10 in the rotation direction of the intermediate transfer member 10. In addition, it is installed at a position upstream of the contact facing portion between the intermediate transfer member 10 and the transfer paper P. The corona charger 62 gives the toner image a true charge having the same polarity as the charge polarity of the toner particles forming the toner image, so that the toner image has sufficient charge for good transfer to the transfer paper P. Give to the toner image. The toner image is charged by the corona charger 62 and then transferred onto the transfer paper P conveyed in the direction of the arrow from the paper supply unit (not shown) by the transfer bias from the transfer roller 22 (secondary transfer). . Thereafter, the transfer paper P onto which the toner image has been transferred is separated from the photoreceptor 40 by a separation device (not shown), subjected to a fixing process by a fixing device (not shown), and then discharged from the device. On the other hand, after the transfer, the untransferred toner is collected and removed by the cleaning device 63, and the residual charge is discharged by the discharging lamp 64 in preparation for the next charging.

Surface layer material of developing belt 41, surface layer prevents contamination of photoreceptor by elastic material, reduces surface friction resistance to transfer belt surface, reduces toner adhesion, and improves cleaning performance and secondary transfer performance Is required. For example, a material that uses one or more of polyurethane, polyester, epoxy resin, etc. to reduce surface energy and increase lubricity, such as fluororesin, fluorine compound, fluorocarbon, titanium dioxide, silicon carbide powder It can be used by dispersing one or more types of particles, particles, or particles with different particle sizes, and by performing heat treatment like a fluorinated rubber material, a surface rich in fluorine can be formed by forming a fluorine-rich layer. The present invention can also be used as a tandem color image forming apparatus. An example of an embodiment of a tandem type color image forming apparatus will be described.

FIG. 3 is a schematic configuration diagram of a tandem type color image forming apparatus.
In the figure, reference numeral 100 is a copying apparatus main body, 200 is a paper feed table on which the copying apparatus is placed, 300 is a scanner mounted on the copying apparatus main body 100, and 400 is an automatic document feeder (ADF) mounted thereon. The copying machine main body 100 is provided with an endless belt-shaped intermediate transfer member 10 at the center. Then, as shown in FIG. 3, in the illustrated example, it is wound around three support rollers 14, 15, and 16 so that it can be rotated and conveyed clockwise in the figure.
In this illustrated example, an intermediate transfer body cleaning device 17 for removing residual toner remaining on the intermediate transfer body 10 after image transfer is provided on the left of the second support roller 15 among the three. Further, among the three images, four images of yellow, cyan, magenta, and black are arranged on the intermediate transfer member 10 stretched between the first support roller 14 and the second support roller 15 along the conveyance direction. The tandem image forming apparatus 20 is configured by arranging the forming units 18 side by side.
An exposure device 21 is further provided on the tandem image forming apparatus 20 as shown in FIG. On the other hand, a secondary transfer device 22 is provided on the side opposite to the tandem image forming apparatus 20 with the intermediate transfer body 10 interposed therebetween. In the illustrated example, the secondary transfer device 22 is configured by spanning a secondary transfer belt 24, which is an endless belt, between two rollers 23, and is pressed against the third support roller 16 via the intermediate transfer body 10. The image on the intermediate transfer body 10 is transferred to a sheet.
A fixing device 25 for fixing the transfer image on the sheet is provided beside the secondary transfer device 22. The fixing device 25 is configured by pressing a pressure roller 27 against a fixing belt 26 that is an endless belt.
The secondary transfer device 22 described above is also provided with a sheet transport function for transporting the image-transferred sheet to the fixing device 25. Of course, a transfer roller or a non-contact charger may be arranged as the secondary transfer device 22, and in such a case, it is difficult to provide this sheet conveying function together.

In the illustrated example, under such a secondary transfer device 22 and a fixing device 25, a sheet reversing device 28 for reversing the sheet so as to record images on both sides of the sheet in parallel with the tandem image forming device 20 described above. Is provided.
When making a copy using this color electrophotographic apparatus, the original is set on the original table 30 of the automatic original conveying apparatus 400. Alternatively, the automatic document feeder 400 is opened, a document is set on the contact glass 32 of the scanner 300, and the automatic document feeder 400 is closed and pressed by it.
When a start switch (not shown) is pressed, when the document is set on the automatic document feeder 400, the document is transported and moved onto the contact glass 32, and then the document is set on the other contact glass 32. At that time, the scanner 300 is immediately driven to travel the first traveling body 33 and the second traveling body 34. Then, the first traveling body 33 emits light from the light source and further reflects the reflected light from the document surface toward the second traveling body 34, and is reflected by the mirror of the second traveling body 34 and passes through the imaging lens 35. The document is placed in the reading sensor 36 and the original content is read.
When a start switch (not shown) is pressed, one of the support rollers 14, 15 and 16 is rotationally driven by a drive motor (not shown), the other two support rollers are driven to rotate, and the intermediate transfer body 10 is rotated and conveyed. To do. At the same time, the individual image forming means 18 rotates the photoconductor 40 to form black, yellow, magenta, and cyan monochrome images on each photoconductor 40. Then, along with the conveyance of the intermediate transfer member 10, the single color images are sequentially transferred to form a composite color image on the intermediate transfer member 10.

On the other hand, when a start switch (not shown) is pressed, one of the paper feed rollers 42 of the paper feed table 200 is selectively rotated, and the sheet is fed out from one of the paper feed cassettes 44 provided in multiple stages in the paper bank 43, and the separation roller 45. Then, the sheets are separated one by one into the paper feed path 46, transported by the transport roller 47, guided to the paper feed path 48 in the copying machine main body 100, and abutted against the registration roller 49 and stopped.
Alternatively, the sheet feed roller 50 is rotated to feed out the sheets on the manual feed tray 51, separated one by one by the separation roller 52, put into the manual feed path 53, and abutted against the registration roller 49 and stopped.
Then, the registration roller 49 is rotated in synchronization with the composite color image on the intermediate transfer member 10, the sheet is fed between the intermediate transfer member 10 and the secondary transfer device 22, and transferred by the secondary transfer device 22. A color image is recorded on the sheet.
The image-transferred sheet is conveyed by the secondary transfer device 22 and sent to the fixing device 25. The fixing device 25 applies heat and pressure to fix the transferred image, and then the switching roller 55 is used to switch the discharge roller. The paper is discharged at 56 and stacked on the paper discharge tray 57. Alternatively, it is switched by the switching claw 55 and put into the sheet reversing device 28, where it is reversed and guided again to the transfer position, and an image is recorded also on the back surface, and then discharged onto the discharge tray 57 by the discharge roller 56.

On the other hand, the intermediate transfer body 10 after the image transfer is removed by the intermediate transfer body cleaning device 17 to remove residual toner remaining on the intermediate transfer body 10 after the image transfer, so that the tandem image forming apparatus 20 can prepare for another image formation.
Here, the registration roller 49 is generally used while being grounded, but it is also possible to apply a bias for removing paper dust from the sheet.
In the tandem image forming apparatus 20 described above, the individual image forming means 18 is more specifically, for example, as shown in the enlarged view of the image forming unit in FIG. A developing device 61, a primary transfer device 62, a photoconductor cleaning device 63, a charge eliminating device 64, and the like are provided.

As the electrophotographic photoreceptor used in the present invention, a conductive support is heated to 50 ° C. to 400 ° C., and a vacuum deposition method, a sputtering method, an ion plating method, a thermal CVD method, a photo CVD method is applied on the support. An amorphous silicon photoconductor (hereinafter referred to as “a-Si-based photoconductor”) having a photoconductive layer made of a-Si can be used by a film forming method such as a plasma CVD method. Among them, a plasma CVD method, that is, a method in which a source gas is decomposed by direct current, high frequency or microwave glow discharge to form an a-Si deposited film on a support is preferably used.
The layer structure of the amorphous silicon photoconductor is, for example, as follows.
FIG. 5 is a schematic configuration diagram for explaining a layer configuration. An electrophotographic photoreceptor 500 shown in FIG. 5A is provided with a photoconductive layer 502 made of a-Si: H, X and having photoconductivity on a support 501. An electrophotographic photoreceptor 500 shown in FIG. 5B includes a photoconductive layer 502 made of a-Si: H, X and having photoconductivity, and an amorphous silicon surface layer 503 on a support 501. It is configured. An electrophotographic photoreceptor 500 shown in FIG. 5C has a photoconductive layer 502 made of a-Si: H, X and having photoconductivity on a support 501, an amorphous silicon surface layer 503, And an amorphous silicon based charge injection blocking layer 504. In the electrophotographic photoreceptor 500 shown in FIG. 5D, a photoconductive layer 502 is provided on a support 501. The photoconductive layer 502 includes a charge generation layer 505 made of a-Si: H, X and a charge transport layer 506, and an amorphous silicon-based surface layer 503 is provided thereon.

The support for the photoreceptor may be conductive or electrically insulating. Examples of the conductive support include metals such as Al, Cr, Mo, Au, In, Nb, Te, V, Ti, Pt, Pd, and Fe, and alloys thereof such as stainless steel. Also, at least the surface of the electrically insulating support such as polyester, polyethylene, polycarbonate, cellulose acetate, polypropylene, polyvinyl chloride, polystyrene, polyamide, etc. A conductively treated support can also be used.
The shape of the support can be a cylindrical or plate-like or endless belt with a smooth or uneven surface, and the thickness thereof is appropriately determined so that a desired photoreceptor for an image forming apparatus can be formed. When flexibility as a photoreceptor for an image forming apparatus is required, it can be made as thin as possible within a range where the function as a support can be sufficiently exhibited. However, the support is usually 10 μm or more from the viewpoints of manufacturing and handling, such as mechanical strength.

The amorphous silicon photosensitive member that can be used in the present invention includes a charge injection blocking layer that functions to prevent charge injection from the conductive support side between the conductive support and the photoconductive layer, if necessary. It is more effective to provide (Fig. 5 (c)). That is, the charge injection blocking layer has a function of blocking charge injection from the support side to the photoconductive layer side when the photosensitive layer is subjected to a charging process with a certain polarity on its free surface. When charged, it has a so-called polarity dependency that does not exhibit such a function. In order to provide such a function, the charge injection blocking layer contains a relatively large number of atoms for controlling conductivity as compared with the photoconductive layer.
The layer thickness of the charge injection blocking layer is preferably from 0.1 to 5 μm, more preferably from 0.3 to 4 μm, and most preferably from 0.5 to 5 in view of obtaining desired electrophotographic characteristics and economic effects. It is desirable to be 3 μm.
The photoconductive layer is formed on the undercoat layer as necessary, and the layer thickness of the photoconductive layer 502 is appropriately determined as desired from the viewpoint of obtaining desired electrophotographic characteristics and economic effects, preferably It is desirable that the thickness is 1 to 100 μm, more preferably 20 to 50 μm, and most preferably 23 to 45 μm.

The charge transport layer is a layer mainly having a function of transporting charges when the photoconductive layer is functionally separated. The charge transport layer includes at least silicon atoms, carbon atoms, and fluorine atoms as constituent elements, and is formed of a-SiC (H, F, O) including hydrogen atoms and oxygen atoms as required. It has conductive properties, particularly charge retention properties, charge generation properties, and charge transport properties. In the present invention, it is particularly preferable to contain an oxygen atom.
The layer thickness of the charge transport layer is appropriately determined as desired from the viewpoints of obtaining desired electrophotographic characteristics and economic effects. The charge transport layer is preferably 5 to 50 μm, more preferably 10 to 40 μm, Optimally, it is desirably 20 to 30 μm.
The charge generation layer is a layer mainly having a function of generating charges when the photoconductive layer is functionally separated. This charge generation layer is composed of a-Si: H containing at least silicon atoms as components and substantially no carbon atoms and, if necessary, hydrogen atoms, and has desired photoconductive properties, particularly charge generation properties. , Has charge transport properties.

The layer thickness of the charge generation layer is appropriately determined as desired from the viewpoint of obtaining desired electrophotographic characteristics and economic effects, etc., preferably 0.5 to 15 μm, more preferably 1 to 10 μm, optimally 1 ˜5 μm.
If necessary, the amorphous silicon photoconductor that can be used in the present invention can be provided with a surface layer on the photoconductive layer formed on the support as described above. It is preferable to form a surface layer. This surface layer has a free surface and is provided to achieve the object of the present invention mainly in moisture resistance, continuous repeated use characteristics, electrical pressure resistance, use environment characteristics, and durability.
The thickness of the surface layer in the present invention is usually 0.01 to 3 μm, preferably 0.05 to 2 μm, and most preferably 0.1 to 1 μm. If the layer thickness is less than 0.01 μm, the surface layer is lost due to wear or the like during use of the photoreceptor, and if it exceeds 3 μm, electrophotographic characteristics such as an increase in residual potential are observed.

FIG. 6 shows a schematic configuration of an example of an image forming apparatus using the contact-type charging device according to the present invention. A photosensitive member as an object to be charged and an image carrier is rotationally driven in the direction of an arrow at a predetermined speed (process speed).
In FIG. 6A, a charging roller 60a, which is a charging member brought into contact with the photosensitive drum, basically has a core metal 60c and a conductive rubber layer 60d concentrically formed on the outer periphery of the core metal 60c. Both ends of the cored bar 60c are rotatably held by a bearing member (not shown) and the like, and the photosensitive drum 40 is pressed with a predetermined pressure by a pressing means (not shown). It rotates following the rotational drive of 40. The charging roller 60a is formed in a diameter of 16 mm by coating a medium resistance rubber layer of about 100,000 Ω · cm on a core metal 60c having a diameter of 9 mm.
The metal core 60c of the charging roller 60a and the illustrated power source 60f are electrically connected, and a predetermined bias is applied to the charging roller 60a by the power source 60f. As a result, the peripheral surface of the photoreceptor 40 is uniformly charged to a predetermined polarity and potential.
The shape of the charging member used in the present invention may take any form such as a magnetic brush or a fur brush in addition to the roller, and can be selected according to the specifications and form of the electrophotographic apparatus. In the case of using a magnetic brush, the magnetic brush is composed of various ferrite particles such as Zn—Cu ferrite as a charging member, a non-magnetic conductive sleeve for supporting it, and a magnet roll included therein. In addition, when using a fur brush, for example, as a material of the fur brush, a fur treated with carbon, copper sulfide, metal, and metal oxide is used, and this is wound around a metal or other conductive core metal. By charging or pasting, it becomes a charger.

In FIG. 6B, a brush roller 60b constituted by a fur brush as a charging member is brought into contact with a predetermined nip width with a predetermined pressing force against the elasticity of the brush portion 60e.
A fur brush roller 60b as a contact charging member in this example is a tape in which a metal cored bar 60c having a diameter of 6 mm which also serves as an electrode and a conductive rayon fiber REC-B manufactured by Unitika Co., Ltd. as a brush portion is piled. Is wound in a spiral shape to form a roll brush having an outer diameter of 14 mm and a longitudinal length of 250 mm. The brush of the brush part has a density of 300 denier / 50 filaments and 155 per square millimeter. This roll brush was inserted into a pipe having an inner diameter of 12 mm while rotating in one direction, and the brush and the pipe were set to be concentric, and left in a high-temperature and high-humidity atmosphere to bend and bevel.
The resistance value of the fur brush roller is 1 × 10 ⁵ Ω at an applied voltage of 100V. This resistance value was converted from the current that flows when a fur brush roller is brought into contact with a metal drum having a diameter of φ30 mm with a nip width of 3 mm and a voltage of 100 V is applied.
The resistance value of the fur brush charger is such that, even when a low-voltage defective portion such as a pinhole is generated on the photosensitive member 40 to be charged, an excessive leakage current flows into this portion, and the charging nip portion becomes poorly charged. 10 ⁴ Ω or more is necessary to prevent image defects, and 10 ⁷ Ω or less is necessary to sufficiently inject charges onto the surface of the photoreceptor 40.
In addition to REC-B manufactured by Unitika Ltd., the brush material is REC-C, REC-M1, REC-M10, SA-7 manufactured by Toray Industries, Inc., Nippon Kashiwa Co., Ltd. It is possible to use Sanderlon manufactured by Kanebo, Beltron manufactured by Kanebo, Kuraray Co., Ltd., Krabobo, carbon dispersed in rayon, Mitsubishi Rayon Co., Ltd. global, etc. One brush is 3 to 10 denier, and preferably has a density of 10 to 100 filaments / bundle and 80 to 600 brushes / mm. The hair foot is preferably 1 to 10 mm.
The fur brush roller 60b is rotationally driven at a predetermined peripheral speed (surface speed) in a direction opposite to the rotation direction (counter) of the photoconductor 40, and contacts the surface of the photoconductor 40 with a speed difference. By applying a predetermined charging voltage from the power source to the fur brush roller 60b, the surface of the rotating photoconductor is uniformly contact-charged to a predetermined polarity and potential. In this example, the contact charging of the photoreceptor 40 by the fur brush roller 60b is performed by direct injection charging, and the surface of the rotating photoreceptor is charged to a potential substantially equal to the applied charging voltage to the fur brush roller 60b.
A magnetic brush may be used as the contact charging member. In the magnetic brush, Zn—Cu ferrite particles having an average particle diameter of 25 μm and Zn—Cu ferrite particles having an average particle diameter of 10 μm are mixed at a weight ratio of 1: 0.05, and peaks at the positions of the respective average particle diameters. Magnetic particles having an average particle diameter of 25 μm and coated with a medium resistance resin layer were used. The contact charging member is composed of the coated magnetic particles prepared above, a nonmagnetic conductive sleeve for supporting the coated magnetic particles, and a magnet roll included therein, and the coated magnetic particles are formed on the sleeve with a thickness. Coating was performed at 1 mm to form a charging nip having a width of about 5 mm between the photosensitive member and the photosensitive member. The gap between the magnetic particle holding sleeve and the photosensitive member was about 500 μm. Further, the magnet roll is rotated so that the sleeve surface rubs in the opposite direction at twice as fast as the circumferential speed of the surface of the photoconductor, and the photoconductor and the magnetic brush are in uniform contact with each other. I did it.

FIG. 7 is a view showing a fixing device according to the present invention.
As shown in FIG. 7, the fixing device 25 is a so-called surf fixing device that rotates and fixes the fixing film 26. More specifically, the fixing film 26 is an endless belt-like heat-resistant film, and is fixed by being held by a driving roller 25c, a driven roller 25b, and a heater support provided below the two rollers. It is stretched around a heating body 25f disposed in a supported manner.
The driven roller 25b also serves as a tension roller for the fixing film 26, and the fixing film 26 is rotationally driven in the clockwise direction by the rotational driving of the driving roller 25c in the clockwise direction in the drawing. The rotational driving speed is adjusted to a speed at which the transfer material and the fixing film 26 have the same speed in the fixing nip region L where the pressure roller 27 and the fixing film 26 are in contact with each other.
Here, the pressure roller 27 is a roller having a rubber elastic layer having good releasability such as silicon rubber, and abutting against the fixing nip region L with a total pressure of 4 to 10 kg while rotating counterclockwise. It is pressed with pressure.
The fixing film 26 preferably has excellent heat resistance, releasability, and durability. A thin film having a total thickness of 100 μm or less, preferably 40 μm or less is used. For example, at least an image of a single layer film or a composite layer film of a heat-resistant resin such as polyimide, polyetherimide, PES (polyether sulfide), PFA (tetrafluoroethylene bar fluoroalkyl vinyl ether copolymer resin), or a 20 μm thick film. On the contact surface side, a release coating layer with a conductive material added to a fluororesin such as PTFE (tetrafluoroethylene resin) or PFA is applied to a thickness of 10 μm, or an elastic layer such as fluororubber or silicon rubber is applied. It is a thing.

In FIG. 7, the heating body 25f of the present embodiment is composed of a planar substrate 25e and a fixing heater 25a. The planar substrate 25e is made of a material having high thermal conductivity and high electrical resistivity, such as alumina. On the surface in contact with the film 26, a fixing heater 25a composed of a resistance heating element is provided in the longitudinal direction. The fixing heater 25a is obtained by coating an electric resistance material such as Ag / Pd or Ta2N in a linear or belt shape by screen printing or the like. In addition, electrodes (not shown) are formed at both ends of the fixing heater 25a, and the resistance heating element generates heat when energized between the electrodes. Further, a fixing temperature sensor 25d constituted by a thermistor is provided on the surface of the substrate opposite to the surface provided with the fixing heater 25a. The substrate temperature information detected by the fixing temperature sensor 25d is sent to a control unit (not shown), and the amount of electric power supplied to the fixing heater 25a is controlled by the control unit, so that the heating body is controlled to a predetermined temperature.
In addition, it is possible to obtain a process cartridge that integrally supports at least one of the photosensitive member according to the present invention and a charging device, a developing device, or a cleaning device and is detachable from the image forming apparatus. By using the toner according to the present invention, the process cartridge can be a process cartridge with excellent image quality.

EXAMPLES The present invention will be further described below with reference to examples, but the present invention is not limited thereto.
In the following, “parts” means parts by weight, and “%” means percent by weight.
(Example 1)
The specific production of the toner according to the present invention will be described below.
<Synthesis of resin fine particle emulsion>
In a reaction vessel equipped with a stir bar and a thermometer, 683 parts of water, 11 parts of sodium salt of ethylene oxide methacrylate adduct sulfate (Eleminol RS-30, manufactured by Sanyo Chemical Industries), 80 parts of styrene, 83 parts of methacrylic acid, When 110 parts of butyl acrylate, 12 parts of butyl thioglycolate and 1 part of ammonium persulfate were added and stirred for 15 minutes at 400 rpm, a white emulsion was obtained. The system was heated to raise the system temperature to 75 ° C. and reacted for 5 hours. Further, 30 parts of a 1% ammonium persulfate aqueous solution was added, and the mixture was aged at 75 ° C. for 5 hours, and an aqueous vinyl resin (a copolymer of styrene-methacrylic acid-butyl acrylate-methacrylic acid ethylene oxide adduct sulfate sodium salt). A dispersion was obtained. This is designated as [fine particle dispersion 1]. The volume average particle size of the [fine particle dispersion 1] measured with a laser diffraction particle size distribution analyzer (LA-920, manufactured by Shimadzu Corp.) was 120 nm. A portion of [Fine Particle Dispersion 1] was dried to isolate the resin component. The Tg of the resin component was 42 ° C., and the weight average molecular weight was 30,000.

<Preparation of aqueous phase>
990 parts of water, 65 parts of [fine particle dispersion 1], 37 parts of a 48.5% aqueous solution of sodium dodecyl diphenyl ether disulfonate (ELEMINOL MON-7 manufactured by Sanyo Chemical Industries) and 90 parts of ethyl acetate were mixed and stirred to give a milky white liquid. Obtained. This is designated as [Aqueous Phase 1].
<Synthesis of low molecular weight polyester>
In a reaction vessel equipped with a condenser, a stirrer and a nitrogen inlet tube, 229 parts of bisphenol A ethylene oxide 2-mole adduct, 529 parts of bisphenol A propylene oxide 3-mole adduct, 208 parts terephthalic acid, 46 parts adipic acid and dibutyl 2 parts of tin oxide was added, reacted at 230 ° C. for 8 hours at normal pressure, and further reacted for 5 hours at a reduced pressure of 10 to 15 mmHg. Then, 44 parts of trimellitic anhydride was added to the reaction vessel, and 2 parts at 180 ° C. and normal pressure. The reaction was performed for a while to obtain [Low molecular weight polyester 1]. [Low molecular polyester 1] had a number average molecular weight of 2500, a weight average molecular weight of 6700, a Tg of 43 ° C., and an acid value of 25.

<Synthesis of intermediate polyester>
In a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen introduction tube, 682 parts of bisphenol A ethylene oxide 2-mole adduct, 81 parts of bisphenol A propylene oxide 2-mole adduct, 283 parts of terephthalic acid, 22 parts of trimellitic anhydride Then, 2 parts of dibutyltin oxide was added, reacted at 230 ° C. for 8 hours at normal pressure, and further reacted for 5 hours at a reduced pressure of 10 to 15 mmHg to obtain [Intermediate Polyester 1]. [Intermediate Polyester 1] had a number average molecular weight of 2,100, a weight average molecular weight of 9,500, Tg of 55 ° C., an acid value of 0.5, and a hydroxyl value of 51.
-Synthesis of a modified polyester resin (referred to as prepolymer 1) capable of reacting with a compound having at least an active hydrogen group-
In a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen introduction tube, 410 parts of the above [intermediate polyester 1], 89 parts of isophorone diisocyanate, and 500 parts of ethyl acetate were added and reacted at 100 ° C. for 5 hours. ] Was obtained. [Prepolymer 1] had a free isocyanate weight% of 1.53%.
<Synthesis of ketimine>
In a reaction vessel equipped with a stir bar and a thermometer, 170 parts of isophoronediamine and 75 parts of methyl ethyl ketone were charged and reacted at 50 ° C. for 5 hours to obtain [ketimine compound 1]. The amine value of [ketimine compound 1] was 418.

<Synthesis of master batch>
1200 parts of water, 40 parts of carbon black (Cabot, Regal 400R), 60 parts of polyester resin (manufactured by Sanyo Kasei, RS801), 30 parts of water are added, and they are mixed with a Henschel mixer (manufactured by Mitsui Mining). The mixture was kneaded at 150 ° C. for 30 minutes using two rolls, rolled and cooled, and pulverized with a pulverizer to obtain [Masterbatch 1].
<Production of oil phase>
In a container equipped with a stir bar and a thermometer, 400 parts of [Low molecular weight polyester 1], 110 parts of carnauba wax and 947 parts of ethyl acetate were charged, heated to 80 ° C. with stirring, and maintained at 80 ° C. for 5 hours. Thereafter, it was cooled to 30 ° C. at 1 hour. Next, 500 parts of [Masterbatch 1] and 500 parts of ethyl acetate were charged in a container and mixed for 1 hour to obtain [Raw material solution 1].
[Raw material solution 1] 1324 parts are transferred to a container, and using a bead mill (Ultra Visco Mill, manufactured by Imex Co., Ltd.), a liquid feeding speed is 1 kg / hr, a disk peripheral speed is 6 m / sec, and 0.5 mm zirconia beads are 80% by volume. The wax was dispersed under the conditions of filling and 3 passes. Next, 1324 parts of a 65% ethyl acetate solution of [low molecular weight polyester 1] was added, and one pass was performed with a bead mill under the above conditions to obtain [pigment / wax dispersion 1]. The solid content concentration of [Pigment / Wax Dispersion 1] (130 ° C., 30 minutes) was 50%.

<Emulsification>
[Pigment / Wax Dispersion 1] 648 parts, [Prepolymer 1] 154 parts, [Ketimine Compound 1] 8.5 parts, and 0.9 part of tertiary amine compound represented by Structural Formula (I) in a container The mixture was mixed for 1 minute at 5,000 rpm with a TK homomixer (manufactured by Tokushu Kika), then 1200 parts of [Aqueous phase 1] was added to the container, and mixed with a TK homomixer at a rotational speed of 10,000 rpm for 20 minutes [emulsification Slurry 1] was obtained.
That is, it is dispersed in an aqueous medium containing resin fine particles and an elongation reaction is performed.
<Desolvent>
[Emulsion slurry 1] was put into a container equipped with a stirrer and a thermometer, and after removing the solvent at 30 ° C. for 8 hours, aging was carried out at 45 ° C. for 4 hours to obtain [Dispersion slurry 1].

<Washing and drying>
[Dispersion Slurry 1] After filtering 100 parts under reduced pressure,
(1): 100 parts of ion-exchanged water was added to the filter cake, mixed with a TK homomixer (10 minutes at 12,000 rpm), and then filtered.
(2): 100 parts of 10% aqueous sodium hydroxide solution was added to the filter cake of (1), mixed with a TK homomixer (30 minutes at 12,000 rpm), and then filtered under reduced pressure.
(3): 100 parts of 10% hydrochloric acid was added to the filter cake of (2), mixed with a TK homomixer (10 minutes at 12,000 rpm), and then filtered.
(4): 300 parts of ion exchanged water was added to the filter cake of (3), mixed with a TK homomixer (10 minutes at 12,000 rpm), and then filtered twice to obtain a cake-like product. . This is designated as [Filter cake 1].
[Filter cake 1] was dried at 45 ° C. for 48 hours in a circulating dryer. Thereafter, the mixture was sieved with a 75 μm mesh to obtain toner base particles. This is designated as [toner base particle 1].
<External additive treatment>
To 100 parts of [Toner Base Particle 1] obtained above, 0.7 part of hydrophobic silica as an external additive and 0.3 part of hydrophobic titanium oxide are mixed with a Henschel mixer to obtain a toner. It was. This is referred to as [Toner 1]. The physical property values of [Toner 1] are listed in Table 1.
<Adjustment of developer>
[Toner 1] A two-component developer comprising 5% by weight and 95% by weight of a copper-zinc ferrite carrier coated with a silicone resin and having an average particle size of 40 μm was prepared. Using a developer, Ricoh's imgio Neo 450, which can print 45 sheets of A4 size paper per minute, was printed continuously and evaluated by the following evaluation method. The evaluation results obtained are shown in Table 2. .

(Example 2)
[Toner 2] was obtained in the same manner as in Example 1 except that in the emulsification of Example 1, the tertiary amine compound represented by the structural formula (I) was changed to 0.6 part.
(Example 3)
[Toner 3] was obtained in the same manner as in Example 1 except that the tertiary amine compound represented by the structural formula (I) was changed to 0.3 part in the emulsification of Example 1.
Example 4
[Toner 4] was obtained in the same manner as in Example 1 except that in the emulsification of Example 1, the tertiary amine compound (triethanolamine manufactured by Wako Pure Chemical Industries, Ltd.) was changed to 0.9 part.
(Comparative Example 1)
[Toner 5] was obtained in the same manner as in Example 1 except that in the emulsification of Example 1, the tertiary amine compound was changed to 0 part.

<Evaluation method>
(Evaluation item)
(1) Measurement of Volume Average Particle Size and (Dv / Dn) The particle size of the toner was measured using a particle size measuring device “Coulter Counter TAII” manufactured by Coulter Electronics Co., Ltd., with an aperture diameter of 100 μm. The volume average particle diameter and the number average particle diameter were determined by the particle size measuring instrument. (Dv / Dn) was automatically calculated from the above values.
(2) Average circularity The average circularity can be measured by a flow particle image analyzer FPIA-2100 (manufactured by Toa Medical Electronics Co., Ltd.). As a specific measurement method, 0.1 to 0.5 ml of a surfactant, preferably an alkylbenzene sulfonate, is added as a dispersant to 100 to 150 ml of water from which impure solids have been removed in advance. About 0.1 to 0.5 g. The suspension in which the sample is dispersed is obtained by performing dispersion treatment for about 1 to 3 minutes with an ultrasonic disperser and measuring the shape and distribution of the toner with the above apparatus at a dispersion concentration of 3000 to 10,000 / μl. .
(3) Charge amount 6 g of developer is weighed, charged into a metal cylinder that can be sealed, and blown to obtain the charge amount. The toner concentration is adjusted to 4.5 to 5.5 wt%.
(4) Cleanability Using an evaluator, the transfer residual toner on the photoconductor that has passed the cleaning process after outputting 100 sheets is transferred to a white paper with a scotch tape (manufactured by Sumitomo 3M Co., Ltd.), and it is transferred to a Macbeth reflection densitometer RD514. Measured with a mold, “◎” indicates that the difference from the blank is less than 0.005, “◯” indicates 0.005-0.010, “Δ” indicates 0.011-0.02, “0” Those exceeding .02 were evaluated as “x”.

(5) Image Density Using an evaluator, after running 150,000 sheets of an image chart with a 50% image area in a single color mode, the solid image was output to 6000 paper manufactured by Ricoh, and the image density was changed to X-Rite ( Measurement was performed by X-Rite). This was performed for four colors alone, and the average was obtained. When this value is less than 1.2, “x”, when it is 1.2 or more and less than 1.4, “△”, when it is 1.4 or more and less than 1.8, “◯”, 1.8 or more and 2 . When less than 2, “」 ”is given.
(6) Image granularity and sharpness Using an evaluator, a photographic image was output in a single color, and the degree of granularity and sharpness was visually evaluated. In order from the best, “◎” is equivalent to offset printing, “○” is slightly worse than offset printing, “△” is much worse than offset printing, “×” is about the same as conventional electrophotographic images (very much Bad).
(7) Background stain After running 30,000 image charts of 50% image area in monochrome mode using an evaluation machine, the blank image is stopped during development, and the developer on the photosensitive member after development is taped. The difference from the image density of the transferred and untransferred tape was measured with a 938 spectrodensitometer (manufactured by X-Rite). The smaller the difference in image density, the better the background stains, and the better ones were ranked in the order of “」 ”,“ ◯ ”,“ Δ ”,“ × ”.
(8) White spots inside character images Using an evaluator, after running 30,000 50% image area image charts in single color mode, the character image is overlaid on a Ricoh type DX OHP sheet in four colors. The toner untransferred frequency at which the inside of the line image of the character portion is lost is compared with the step sample. Rank 1 is the lowest and rank 5 is the highest. In the case of rank 1 or 2, “X” was assigned, “△” was assigned in rank 3, “◯” was given in rank 4, and “◎” was given in rank 5.

(9) Toner fluidity A powder tester (PT-N type, manufactured by Hosokawa Micron) is loaded with meshes of 75 μm, 45 μm, and 22 μm openings in order from the top, and 2 g of the toner base is put on the uppermost 75 μm mesh. Then, a vibration of 1 mm in the vertical direction was applied for 10 seconds, and the fluidity (cohesion degree) of the toner base was calculated from the residual amount of toner on each mesh.
Aggregation degree (%) = (5 × (remaining toner amount (g) on 75 μm mesh))
+ 3 × (residual toner amount on 45 μm mesh (g))
+ (Residual toner amount on 22 μm mesh (g))) × 10
When the degree of aggregation was 8% or less, “◎”, when it was 8 to 16%, “◯”, when it was 16 to 25%, “Δ”, and when it was 25% or more, “X”.
(10) Fixability Using an evaluation machine, a plain image and a thick paper transfer paper (manufactured by Ricoh, type 6200 and NBS Ricoh copy printing paper <135>) with a solid image of 0.85 ± 0.1 mg / cm ² The fixing was evaluated by the toner adhesion amount. A fixing test was performed by changing the temperature of the fixing belt, and an upper limit temperature at which hot offset did not occur on plain paper was defined as an upper limit fixing temperature. Further, the minimum fixing temperature was measured with a thick paper. The lower limit fixing temperature was determined as the fixing lower limit temperature at the fixing roll temperature at which the residual ratio of the image density after rubbing the obtained fixed image with a pad was 70% or more. The fixing upper limit temperature is “◎” when the temperature is 190 ° C. or higher, “◯” when the temperature is 190 to 180 ° C., “Δ” when the temperature is 180 to 170 ° C., and “X” when the temperature is 170 ° C. or lower. The lower limit fixing temperature is “◎” when it is 135 ° C. or less, “◯” when it is 135 to 145 ° C., “Δ” when it is 145 to 155 ° C., and “X” when it is 155 ° C. or more.

1 is a schematic configuration diagram of an image forming apparatus according to the present invention. FIG. 2 is a diagram illustrating an apparatus configuration in which a developing unit is provided around a photoconductor. 1 is a schematic configuration diagram of a tandem color image forming apparatus. FIG. 4 is an enlarged view of an image forming unit in FIG. 3. It is a typical block diagram for demonstrating the layer structure of an amorphous silicon photoconductor. It is a figure which shows the charging device which concerns on this invention. 1 is a diagram illustrating a fixing device according to the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Intermediate transfer body 14, 15, 16 Support roller 17 Intermediate transfer body cleaning apparatus 18 Image forming means 20 Tandem image forming part 21 Exposure apparatus 22 Secondary transfer apparatus (transfer roller)
23 roller 24 secondary transfer belt 25 fixing device 25a fixing heater 25b driven roller 25c driving roller 25d fixing temperature sensor 25e flat substrate 26 fixing belt (fixing film)
27 Pressure roller 28 Sheet reversing device 32 Contact glass 33 First traveling body 34 Second traveling body 35 Imaging lens 36 Reading sensor 40 Photoconductor 41 Developing belt 42 Paper feed roller 43 Paper bank 44 Paper feed cassette 45 Separating roller 46, 48 Feeding path 47 Conveying roller 49 Registration roller 50 Feeding roller 51 Manual feed tray 52 Separating roller 53 Manual feeding path 55 Switching claw 56 Ejection roller 57 Ejection tray 60 Charging device 60a Charging roller 60b Brush roller 60c Core metal 60d Conductive rubber Layer 60e Brush portion 60f Power supply 61 Developing device 62 Primary transfer device 63 Cleaning device 64 Static elimination device (static elimination lamp)
DESCRIPTION OF SYMBOLS 100 Copier main body 200 Paper feed table 300 Scanner 400 Automatic document feeder P Transfer paper

Claims (13)

At least an organic solvent phase in which an isocyanate group- containing polyester resin is dissolved, an amine, and a colorant are dispersed in an aqueous medium phase in which resin fine particles are dispersed, and the isocyanate group- containing polyester resin and the amine are dispersed. to cause an extension reaction and / or crosslinking reaction with the kind, comprising thereby a toner for developing electrostatic images to form particles from the dispersion obtained, in that it contains tertiary amine compound in an organic solvent phase A toner for developing an electrostatic charge image. The electrostatic image developing toner according to claim 1, wherein the tertiary amine compound is represented by the following structural formula (I).

In the organic solvent phase, a non-reactive polyester is further dissolved together with the functional group-containing polyester resin, and the weight ratio of the functional group-containing polyester resin to the non-reactive polyester is 5/95 to 75/25. The toner for developing an electrostatic charge image according to claim 1 or 2. 4. The electrostatic image developing toner according to claim 1, wherein the toner particles have a volume average particle diameter of 3 to 8 [mu] m. 5. The electrostatic image developing toner according to claim 1, wherein Dv / Dn of the toner particles is 1.25 or less. 6. The electrostatic image developing toner according to claim 1, wherein the toner particles have an average circularity of 0.900 to 0.980. A two-component developer comprising at least a carrier comprising the toner according to claim 1 and magnetic particles. An electrostatic charge image carrier that forms a latent image, a charging unit that uniformly charges the surface of the image carrier, an exposure unit that exposes the charged image carrier surface based on image data and writes a latent image, and an image A developing means for supplying toner to the latent image formed on the surface of the carrier and making it visible, a cleaning means for cleaning the surface of the image carrier, a charge eliminating means for eliminating charge on the surface of the image carrier, and an image carrier Claims 1 to 6 comprising contact transfer means for transferring the visible image of the body surface directly or onto an intermediate transfer body and then transferring it to a recording medium, and heat fixing means for fixing the toner image on the recording medium. An image forming apparatus using the electrostatic image developing toner according to any one of the above. The image forming apparatus according to claim 8, wherein the charging unit is a charging device that performs charging by bringing a charging member into contact with the electrostatic charge image carrier and applying a voltage to the charging member. The image forming apparatus according to claim 8, wherein the electrostatic charge image carrier is an amorphous silicon electrostatic charge image carrier. The heat fixing unit includes a heating body including a heating element, a film in contact with the heating body, and a pressure member in pressure contact with the heating body through the film, and between the film and the pressure member. 11. The image forming apparatus according to claim 8, wherein the image forming apparatus is a fixing device that heats and fixes a recording material on which an unfixed image is formed. In a process cartridge that integrally supports at least one means selected from an electrostatic charge image bearing member photosensitive member, a charging means, a developing means, and a cleaning means, and is detachable from an image forming apparatus.
7. A process cartridge according to claim 1, wherein the developing means holds toner, and the toner is at least an electrostatic image developing toner according to any one of claims 1 to 6. An image forming apparatus comprising the process cartridge according to claim 12.

Images