JP4777750B2 - Electrophotographic toner manufacturing method, electrophotographic toner, electrophotographic developer, image forming method, and image forming apparatus - Google Patents

Description

  The present invention relates to a method for producing an electrophotographic toner, an electrophotographic toner, an electrophotographic developer, an image forming method, and an image forming apparatus used in an electrophotographic image forming apparatus such as a copying machine, a printer, and a facsimile machine. .

  In recent years, there have been remarkable developments in equipment used in information processing systems using electrophotography. In particular, the print quality and reliability of laser printers and digital copying machines that convert information into digital signals and record information by light are remarkable. Furthermore, they have been applied to laser printers or digital copiers capable of full-color printing by merging with high-speed technology.

  From such a background, as a required photoreceptor function, it is an important issue to form a high-quality, high-quality image. Improvements have been made to further reduce.

  However, the particle shape of the toner is usually indeterminate in the conventional kneading and pulverizing method, and when used as a one-component developer in the machine, the developing roller and the toner supply are used. The toner is further pulverized by contact stress caused by a roller, a layer thickness regulating blade, a friction charging blade, etc., and fine particles are generated, or a fluidizing agent is embedded in the toner surface, resulting in a decrease in image quality. ing.

  Further, because of its shape, the fluidity as a powder is poor, a large amount of fluidizing agent is required, and the filling rate into the toner bottle is low, which is an obstacle to downsizing. Therefore, the current situation is that the merit of reducing the particle size is not utilized. Furthermore, the pulverization method has a limit on the particle size and cannot cope with further reduction in the particle size. In addition, in order to produce a full-color image, the transfer process of an image formed from multicolor toner from a photoconductor to a transfer medium or paper has become complicated, and transferability due to an irregular shape such as pulverized toner is also increased. Due to the poorness of the image, there have been problems such as missing of the transferred image and a large amount of toner consumption to compensate for it.

  Accordingly, there is a growing demand for further improvement in transfer efficiency to reduce toner consumption to obtain a high-quality image without missing images and to reduce running costs. If the transfer efficiency is very good, there is no need for a cleaning unit for removing untransferred toner from the photoconductor or transfer medium, and there is an advantage that the apparatus can be reduced in size and cost and waste toner is eliminated. Because.

  As a method for solving these problems, a toner production method using a suspension polymerization method or an emulsion polymerization aggregation method has been studied. Patent Document 1 discloses that a polyester resin and a colorant are dispersed and dissolved in a volatile solvent such as a low boiling point organic solvent, and this is emulsified and formed into droplets in an aqueous medium in which an inorganic dispersant is present. A method of removing the solvent, called a polymer dissolution suspension method with volume shrinkage, has been proposed. Unlike suspension polymerization and emulsion polymerization aggregation methods, this method has a wide range of versatile resins that can be used, and is particularly useful for full-color processes that require transparency and smoothness of the image area after fixing. It is excellent in that it can be used.

Patent Document 2 discloses an emulsifying machine comprising a toner composition mixed solution in which a binder resin and a colorant are dissolved or dispersed in a solvent and an aqueous medium containing an inorganic dispersant in order to eliminate the above-described batch-type defects. A manufacturing method for continuously supplying to the substrate has been proposed. This method is intended to control the particle size distribution by the number of passes through the emulsifier. However, the dispersion state of the release agent and the colorant inside the toner changes, and the required quality changes each time. is there.
Therefore, it is conceivable to adjust the particle size depending on the amount of the dispersant in the aqueous phase. However, if a surfactant is introduced into the aqueous phase at once, it is difficult to adjust the particle size thereafter, and extra Raw materials must be used, wasting time and resources.
JP-A-7-152202 JP 2001-255695 A

  The present invention has been made in view of the above circumstances. In a toner manufacturing method in which a liquid in which constituent components of a toner are dissolved or dispersed in an organic solvent and an aqueous medium are continuously supplied to an emulsifier, separation of the inside of the toner is performed. Method for producing electrophotographic toner capable of adjusting particle size without changing dispersion state of mold agent and colorant and obtaining desired particle size distribution, developer using electrophotographic toner, image forming method, image An object is to provide a forming apparatus.

  In order to achieve the above object, in the method for producing an electrophotographic toner according to claim 1, at least a resin, a colorant, and a release agent are dissolved or dispersed in an organic solvent, and a solid hardly soluble in water. A toner manufacturing method in which an aqueous medium (aqueous phase) containing a fine particle dispersant is continuously fed to an emulsifier, emulsified and dispersed, and aggregated to the toner size before and after removing the organic solvent and removing the particles. In addition, it is characterized in that a dispersing agent is added during mixing of the aqueous phase and mixed in the pipe.

  According to a second aspect of the present invention, there is provided a method for producing an electrophotographic toner according to the first aspect of the invention, wherein the amount of liquid delivery of the dispersant is arbitrarily changed.

  The invention according to claim 3 is the method for producing the toner for electrophotography according to claim 1 or 2, wherein the amount of the liquid feed of the dispersant is 1.0 to 10.0% with respect to the amount of the liquid to be estimated. It is the range of these.

  The invention according to claim 4 is characterized in that the solid content concentration when the dispersant and the aqueous medium are mixed in the pipe is in the range of 4.0 to 15.0%.

  A fifth aspect of the present invention is a toner obtained by the method for producing an electrophotographic toner according to any one of the first to fourth aspects, wherein the toner has a volume average particle diameter (Dv) of 4.0 μm to 8 μm. The volume average particle diameter (Dv) / number average particle diameter (Dn) of the toner is 1.05 to 1.20.

  The invention described in claim 6 has the electrophotographic toner described in claim 5.

  According to a seventh aspect of the present invention, there is provided a charging step of applying a voltage to the charging member from the outside to charge the charged member, a step of forming an electrostatic charge image on the charged charged member, and an electrostatic charge image. A developing step for developing with toner to form a toner image, a transfer step for applying a voltage to the transfer member from the outside to transfer the toner image onto the transfer member, and a surface of the charged member after transfer are cleaned with a cleaning member. An image forming method comprising a cleaning step and a fixing step for heat-fixing a toner image, wherein the electrophotographic toner according to claim 5 is used from the developing step to the fixing step.

According to an eighth aspect of the present invention, there is provided a charger for charging the photosensitive member, and the information obtained by irradiating light to the charged photosensitive member based on the information obtained by reading and digitizing the information from the document is written and statically written. An exposure unit that forms an electrostatic latent image, a developing unit that develops the photosensitive member on which the electrostatic latent image is formed with toner, a transfer unit that transfers the development to the medium, and a fixing unit that fixes the transferred development to the medium An image forming apparatus comprising: a cleaning unit that cleans a non-transferred part after transfer and a photosensitive member with dirt; and a recycling unit that collects toner collected by cleaning. It is an electrophotographic toner.

  According to the present invention, since the dispersant is added and mixed in the pipe while the aqueous phase is being fed, the dispersant can be added in an arbitrary amount instead of being added all at once. The particle size can be adjusted, and a desired particle size distribution can be obtained.

Hereinafter, this embodiment will be described in detail with reference to the drawings.
FIG. 1 shows an example of a continuous emulsification apparatus for producing using the toner production method according to the present embodiment. The continuous emulsification apparatus shown in FIG. 1 includes an oil phase 1 in which a toner composition containing a resin, for example, an unmodified polyester resin, a colorant and a release agent, is dissolved or dispersed in an organic solvent or an organic dispersant, and an isocyanate bond. An oil phase 2 containing a prepolymer having a water, an aqueous medium (aqueous phase 1) containing a solid fine particle dispersant hardly soluble in water, a dispersant such as a surfactant, a static mixer, and an emulsifier As shown in FIG. 1, the dispersant is added in the middle of feeding the aqueous phase, mixed in a static mixer, and then fed to an emulsifier.

  As described above, the present embodiment is characterized in that the dispersant is added during the feeding of the aqueous phase, mixed in the static mixer, and then fed to the emulsifier. That is, according to such a method, the dispersant can be added in an arbitrary amount rather than being charged at once, so that the subsequent particle size adjustment can be easily performed and an extra raw material is used. There is no need.

  The amount of the dispersant added during the feeding of the aqueous phase is preferably 1.0% to 10.0% as the dispersing agent feeding amount relative to the aqueous phase feeding amount, and the solid content when mixed with the aqueous phase. The concentration is preferably 4.0% to 15.0%. If the solid content concentration is obtained when the aqueous phase and the dispersant are mixed in such a ratio of the amount of the liquid delivered to the dispersant, the particle size distribution is small, that is, the volume average particle size (Dv) is sharp. A toner having a volume average particle diameter (Dv) / number average particle diameter (Dn) of 1.05 to 1.20 in a range of 4.0 μm to 8.0 μm can be obtained, and an image with high image quality can be formed.

Next, materials used in the toner manufacturing method of this embodiment will be described in detail.
First, as the toner binder, any resin that is used for normal toners such as styrene acrylic resin, polyol resin, and polyester resin can be applied. Polyester resins are preferred.

(Modified polyester resin)
The polyester resin suitable for this embodiment may be a modified polyester resin. The modified polyester resin is a polyester resin in which a functional group contained in a monomer unit such as an acid or alcohol and a bonding group other than an ester bond exist, or a resin component having a different configuration in a polyester resin has a covalent bond or an ion. A resin bonded by bonding or the like.
For example, a resin obtained by reacting the terminal of a polyester resin with something other than an ester bond can be mentioned. Specifically, a resin in which a functional group such as an acid group or an isocyanate group that reacts with a hydroxyl group is introduced into the terminal end and then further reacted with an active hydrogen compound to modify the terminal end or undergo an extension reaction is also included.
Further, if the compound has a plurality of active hydrogen groups, a resin in which the polyester ends are bonded to each other is also included (such as urea-modified polyester and urethane-modified polyester).

In addition, a reactive group such as a double bond is introduced into the polyester main chain, and radical polymerization is performed at the introduction site, and a carbon-carbon bond graft component is introduced into the side chain, or double bonds are bridged. Also included (styrene modified, acrylic modified polyester, etc.).
Further, it may be a resin obtained by copolymerizing resin components having different structures in the main chain of the polyester or reacting with a terminal carboxyl group or hydroxyl group. For example, those obtained by copolymerization with a silicone resin having a terminal modified with a carboxyl group, a hydroxyl group, an epoxy group, or a mercapto group (such as a silicone-modified polyester) are also included.

Hereinafter, the modified polyester resin will be specifically described.
(Urea-modified polyester resin)
Examples of the modified polyester resin include modified polyester (i) having a urea bond. Examples of the modified polyester (i) include a reaction product of a polyester prepolymer (A) having an isocyanate group and amines (B). 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.

  The ratio of the polyol (1) and the polycarboxylic acid (2) is usually 2/1 to 1/1, preferably 1. as the equivalent ratio [OH] / [COOH] of the hydroxyl group [OH] and the carboxyl group [COOH]. 5/1 to 1/1, more preferably 1.3 / 1 to 1.02 / 1.

  Examples of the polyisocyanate (3) include aliphatic polyisocyanates (tetramethylene diisocyanate, hexamethylene diisocyanate, 2,6-diisocyanatomethylcaproate, etc.); alicyclic polyisocyanates (isophorone diisocyanate, cyclohexylmethane diisocyanate, etc.); Diisocyanates (tolylene diisocyanate, diphenylmethane diisocyanate, etc.); araliphatic diisocyanates (α, α, α ′, α′-tetramethylxylylene diisocyanate, etc.); isocyanurates; polyisocyanates with phenol derivatives, oximes, caprolactams, etc. Blocked; and combinations of two or more of these.

  The ratio of the polyisocyanate (3) is usually 5/1 to 1/1, preferably 4 /, as the equivalent ratio [NCO] / [OH] of the isocyanate group [NCO] and the hydroxyl group [OH] of the polyester having a hydroxyl group. 1 to 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 content of the polyisocyanate (3) component in the prepolymer (A) having an isocyanate group at the terminal is usually 0.5 to 40% by weight, preferably 1 to 30% by weight, more preferably 2 to 20% by weight. It is. If it is less than 0.5% by weight, the hot offset resistance deteriorates, and it is disadvantageous in terms of both heat-resistant storage stability and low-temperature fixability. On the other hand, if it exceeds 40% by weight, the low-temperature fixability deteriorates.

  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 urea-modified polyester will be low, and the hot offset resistance will deteriorate.

  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 B1 to B5 blocked amino groups (B6) include ketimine compounds and oxazoline compounds obtained from 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.

  If necessary, the molecular weight of the urea-modified polyester can be adjusted. Examples of the elongation terminator include monoamines (diethylamine, dibutylamine, butylamine, laurylamine, etc.), and those obtained by blocking them (ketimine compounds).

  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). Usually, it is 1/2 to 2/1, preferably 1.5 / 1 to 1 / 1.5, and more preferably 1.2 / 1 to 1 / 1.2. When [NCO] / [NHx] exceeds 2 or less than 1/2, the molecular weight of the urea-modified polyester (i) becomes low, and the hot offset resistance deteriorates. In the present invention, the polyester (i) modified with a urea bond may contain a urethane bond together with a urea bond. The molar ratio of the urea bond content and the urethane bond content is usually 100/0 to 10/90, preferably 80/20 to 20/80, and more preferably 60/40 to 30/70. . When the molar ratio of the urea bond is less than 10%, the hot offset resistance is deteriorated.

  The urea-modified polyester (i) in the present embodiment is produced by a one-shot method or a prepolymer method. The weight average molecular weight of the urea-modified polyester (i) is usually 10,000 or more, preferably 20,000 to 10,000,000, more preferably 30,000 to 1,000,000. If it is less than 10,000, the hot offset resistance deteriorates. The number average molecular weight of the urea-modified polyester is not particularly limited when the unmodified polyester (ii) described later is used, and may be a number average molecular weight that can be easily obtained to obtain a weight average molecular weight. (I) When used alone, the number average molecular weight is usually 20000 or less, preferably 1000 to 10000, and more preferably 2000 to 8000. When it exceeds 20000, the low-temperature fixability and the glossiness when used in a full-color apparatus are deteriorated.

(Unmodified polyester resin)
In the present invention, not only the polyester (i) modified with a urea bond can be used alone, but also the polyester (ii) not modified can be contained as a toner binder component together with this (i). By using (ii) in combination, the low-temperature fixability and glossiness when used in a full-color apparatus are improved, which is preferable to single use. Examples of (ii) include the same polycondensates of polyol (1) and polycarboxylic acid (2) as in the polyester component of (i), and preferred ones are also the same as (i). (Ii) is not limited to unmodified polyester, but may be modified with a chemical bond other than a urea bond, and may be modified with a urethane bond, for example. It is preferable that (i) and (ii) are at least partially compatible with each other in terms of low-temperature fixability and hot offset resistance. Accordingly, the polyester component (i) and (ii) preferably have similar compositions. When (ii) is contained, the weight ratio of (i) and (ii) is usually 5/95 to 80/20, preferably 5/95 to 30/70, more preferably 5/95 to 25/75, Particularly preferred is 7/93 to 20/80. If the weight ratio of (i) 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 of (ii) is usually 1000-30000, preferably 1500-10000, more preferably 2000-8000. 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 (ii) 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 (ii) is usually 1-30, preferably 5-20. By having an acid value, it tends to be negatively charged.

  In this embodiment, the glass transition point (Tg) of the toner binder is usually 50 to 70 ° C., preferably 55 to 65 ° C. If it is less than 50 ° C., the heat resistant storage stability of the toner is deteriorated, and if it exceeds 70 ° C., the low-temperature fixability becomes insufficient. Due to the coexistence of the urea-modified polyester resin, the dry toner according to the present invention tends to have good heat-resistant 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 binder, the temperature (TG ′) at which 10000 dyne / cm 2 is obtained at a measurement frequency of 20 Hz 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 binder, the temperature (Tη) at 1000 poise 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.

(Coloring agent)
As the colorant in this embodiment, 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 oxidation Iron, 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, Faisa Red, Para Lortho Nitroaniline Red, Resol Fast Scarlet G, Brilliant Fast Scarlet, Brilliant Carnmin BS, 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, Pogment Scarlet 3B, Bordeaux 5B, Toluidine 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, Lazolone Red, Polyazo Red, Chrome Vermilion, Benzidine Orange, Perinone Orange, Oil Orange, Cobalt Blue, Cerulean Blue, Alkaline Blue Lake, Peacock Blue Lake, Victoria Blue Lake, Metal Free Phthalocyanine Blue, Phthalocyanine Blue, Fast Sky Blue, Indance Ren 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 Grits Enlake, 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, based on the toner.

(Master Badge)
The colorant used in this embodiment can also be used as a master batch combined with a resin. As the binder resin to be kneaded together with the production of the masterbatch or the masterbatch, in addition to the modified and unmodified polyester resins mentioned above, styrene such as polystyrene, poly p-chlorostyrene, polyvinyltoluene, and polymers of substituted products thereof; Styrene-p-chlorostyrene copolymer, styrene-propylene copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer Styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer, styrene-α- Chloromethyl methacrylate copolymer, Tylene-acrylonitrile copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile-indene copolymer, styrene-maleic acid copolymer, styrene-malein Styrene copolymers such as acid ester copolymers; polymethyl methacrylate, polybutyl methacrylate, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, polyester, epoxy resin, epoxy polyol resin, polyurethane, polyamide, polyvinyl butyral, poly Acrylic resin, rosin, modified rosin, terpene resin, aliphatic or alicyclic hydrocarbon resin, aromatic petroleum resin, chlorinated paraffin, paraffin wax, etc. The

  The master batch in this embodiment can obtain a master batch by mixing and kneading a resin for a master batch and a colorant under a high shear force. At this time, an organic solvent can be used to enhance the interaction between the colorant and the resin. Also, a so-called flushing method called watering paste containing water of a colorant is mixed and kneaded together with a resin and an organic solvent, and the colorant is transferred to the resin side to remove moisture and organic solvent components. Since it can be used as it is, it does not need to be dried and is preferably used. For mixing and kneading, a high shear dispersion device such as a three-roll mill is preferably used.

(Release agent)
Further, a release agent such as wax may be contained together with the toner binder and the colorant. Known waxes can be used, and examples thereof include polyolefin waxes (polyethylene wax, polypropylene wax, etc.); long-chain hydrocarbons (paraffin wax, sazol wax, etc.); carbonyl group-containing waxes, and the like. 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. -Octadecandiol diol distearate, etc.); polyalkanol esters (tristearyl trimellitic acid, distearyl maleate, etc.); polyalkanoic acid amides (ethylenediamine dibehenyl 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 content of the wax in the toner is usually 0 to 40% by weight, preferably 3 to 30% by weight.

(Charge control agent)
If necessary, a charge control agent may be contained. 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 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 a phenol-based condensate (above, Orient Chemical Industry Co., Ltd.), TP-302 of a quaternary ammonium salt molybdenum complex, TP 1415 (above, Hodogaya Chemical Industry Co., Ltd.), quaternary ammonium Copy charge PSY VP2038 of salt, copy blue PR of triphenylmethane derivative, copy charge of quaternary ammonium salt NEG VP2036, copy charge NX VP434 (above, manufactured by Hoechst), LRA-901, LR-147 which is a boron complex (Nippon Carlit), copper phthalocyanine, perylene, quinacridone Azo pigments, sulfonate group, carboxyl group, and polymer compounds having a functional group such as a quaternary ammonium salt.

  In this embodiment, 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. Although it is not a thing, Preferably it is used in 0.1-10 weight part with respect to 100 weight part of 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 and mold release agents can be melt-kneaded together with the master batch and the resin, and of course, they may be added when dissolved and dispersed in an organic solvent.

(Solid fine particle dispersant)
The toner production method of the present embodiment is emulsified with an oil phase obtained by dissolving or dispersing the above-described resin, colorant, release agent, and the like in an organic solvent and an aqueous medium (aqueous phase). The solid fine particle dispersant is dispersed.
The solid fine particle dispersant exists in an aqueous medium as a solid that is hardly soluble in water, and preferably has an average particle size of 0.01 to 1 μm.

  Examples of inorganic fine particle dispersants include silica, alumina, titanium oxide, barium titanate, magnesium titanate, calcium titanate, strontium titanate, zinc oxide, tin oxide, silica sand, clay, mica, wollastonite, and diatomaceous earth. Examples include soil, chromium oxide, cerium oxide, bengara, antimony trioxide, magnesium oxide, zirconium oxide, barium sulfate, barium carbonate, calcium carbonate, silicon carbide, and silicon nitride.

  More preferably, tricalcium phosphate, calcium carbonate, colloidal titanium oxide, colloidal silica, hydroxyapatite and the like can also be used. In particular, hydroxyapatite synthesized by reacting sodium phosphate and calcium chloride in water under a basic condition is preferable.

  The organic solid fine particle dispersant is copolymerized with a monomer having a carboxyl group such as methacrylic acid obtained by microcrystals of low molecular weight organic compounds or polymer fine particles, for example, soap-free emulsion polymerization, suspension polymerization, or dispersion polymerization. Polystyrene particles such as polystyrene, methacrylic acid ester, acrylic acid ester copolymer, polycondensation systems such as silicone, benzoguanamine, and nylon, and thermosetting resin.

  After adjusting the solid fine particle dispersant in water, an inorganic substance that can be dissolved in an acid such as tricalcium phosphate is partially dissolved by adding a necessary amount of hydrochloric acid or the like in advance. The addition amount of the acid is preferably 0.01% to 10%, more preferably 0.1% to 5% of the amount capable of completely dissolving the inorganic substance.

  In the case of using a polymer fine particle copolymerized with (meth) acrylic acid having a carboxyl group as a solid fine particle dispersant, a necessary amount of a base such as sodium hydroxide is added and partially Dissolve. The amount of alkali added is preferably 0.01% to 10%, more preferably 0.1% to 5% of the amount capable of completely dissolving the inorganic substance.

(Dispersant)
As described above, the solid fine particle dispersant is dispersed in the aqueous medium, but the dispersant is used in combination to adjust the adsorptivity of the solid fine particles to the droplets and to control the particle size distribution. Examples of such dispersing agents include anionic surfactants such as alkylbenzene sulfonates, α-olefin sulfonates, phosphate esters, alkylamine salts, amino alcohol fatty acid derivatives, polyamine fatty acid derivatives, and amine salt types such as imidazoline. And quaternary ammonium salt type cationic surfactants such as alkyltrimethylammonium salt, dialkyldimethylammonium salt, alkyldimethylbenzylammonium salt, pyridinium salt, alkylisoquinolinium salt, benzethonium chloride, fatty acid amide derivatives, Nonionic surfactants such as polyhydric alcohol derivatives such as alanine, sodium dodecyl diphenyl ether disulfonate, dodecyl di (aminoethyl) glycine, di (octylaminoethyl) glycine and N-alkyl-N, N Amphoteric surfactants such as dimethyl ammonium betaine and the like.

Further, by using a surfactant having a fluoroalkyl group, the effect can be obtained in a very small amount. Examples of the anionic surfactant having a fluoroalkyl group that is preferably used include fluoroalkyl carboxylic acids having 2 to 10 carbon atoms and metal salts thereof, disodium perfluorooctanesulfonyl glutamate, 3- [ω-fluoroalkyl (C _6- C ₁₁ ) oxy] -1-alkyl (C ₃ -C ₄ ) sodium sulfonate, 3- [ω-fluoroalkanoyl (C ₆ -C ₈ ) -N-ethylamino] -1-propanesulfonic acid sodium, fluoroalkyl (C ₁₁ -C ₂₀ ) carboxylic acid and its metal salt, perfluoroalkyl carboxylic acid (C ₇ -C ₁₃ ) and its metal salt, perfluoroalkyl (C ₄ -C ₁₂ ) sulfonic acid and its metal salt, perfluoro Octanesulfonic acid diethanolamide, N-propyl-N- (2hydroxyethyl) perfluoro Click Tan sulfonamide, perfluoroalkyl (C ₆ ~C ₁₀₎ sulfonamide propyl trimethyl ammonium salts, perfluoroalkyl (C ₆ ~C ₁₀₎ -N- ethylsulfonyl glycine salts, monoperfluoroalkyl (C ₆ ~C ₁₆₎ Examples thereof include ethyl phosphate.

  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 (Daikin Kogyo Co., Ltd.), MegaFuck F-l10, 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 Co., Ltd.), and Fgentent F-100, F-150 (manufactured by Neos).

  Examples of cationic surfactants include aliphatic primary, secondary or secondary amine acids having a fluoroalkyl group, aliphatic quaternary ammonium salts such as perfluoroalkyl (C6-C10) sulfonamidopropyltrimethylammonium salt, benza Luconium salt, benzethonium chloride, pyridinium salt, imidazolinium salt, trade names include Surflon S-121 (Asahi Glass), Florard FC-135 (Sumitomo 3M), Unidyne DS-202 (Daikin Industries) Megafac F-150, F-824 (Dainippon Ink Co., Ltd.), Xtop EF-132 (Tochem Products Co., Ltd.), Footgent F-300 (Neos Co., Ltd.) and the like.

  The stabilization of the dispersed droplets may be adjusted 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 Such as β-hydroxyethyl acrylate, β-hydroxyethyl methacrylate, β-hydroxypropyl acrylate, β-hydroxypropyl methacrylate, γ-hydroxypropyl acrylate, γ-hydroxypropyl methacrylate, 3-chloroacrylate 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, etc., or esters of compounds containing vinyl alcohol and carboxyl groups, such as Vinyl acetate, vinyl propionate, vinyl butyrate, acrylamide, methacrylamide, diacetone acrylamide or their methylol compounds, acid chlorides such as acrylic acid chloride, methacrylic acid chloride, pinylpyridine, vinylpyrrolidone, vinylimidazole, ethyleneimine, etc. Homopolymers or copolymers such as those having nitrogen atoms or heterocyclic rings thereof, polyoxyethylene, polyoxypropylene, polymers 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.

Next, a toner manufacturing method will be described.
(Aqueous medium)
In the toner manufacturing method of the present embodiment, an aqueous medium is used. As an aqueous medium to be used, water alone may be used, but 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. In addition, an organic solvent such as an ester such as ethyl acetate can be used in combination with water.

(Addition of dispersant)
As described above, the solid fine particle dispersant is dispersed in the aqueous medium, and the dispersant is used in combination to adjust the adsorptivity of the solid fine particle dispersant to the droplets and to control the particle size distribution.
In the present invention, this dispersant is added while the aqueous medium (aqueous phase) is fed to the emulsifier, and mixed in the pipe by a static mixer.
The amount of dispersant added (dispersing agent feeding amount) is adjusted depending on the particle size distribution, but the dispersing agent feeding amount is preferably 1.0 to 10.0% of the feeding amount of the aqueous medium. If the amount of the liquid delivered to the dispersant is less than 1.0%, solid particles are not completely adsorbed by the dispersant, the coarse powder content increases, and the particle size distribution becomes broad. On the other hand, if the amount exceeds 10.0%, the solid particle droplet adsorption becomes excessively active, and a lot of fine powder is generated. After that, these particles are coalesced into a coarse powder, and the particle size distribution is not sharpened. In the present invention, the flow rate of the dispersant is arbitrarily changed, and is controlled by a pump, but is not particularly limited. However, it is desirable that there is no pulsating flow.

(Preparation of toner composition)
The toner binder can be produced by the following method. The polyol (1) and the polycarboxylic acid (2) are heated to 150 to 280 ° C. in the presence of a known esterification catalyst such as tetrabutoxytitanate or dibutyltin oxide, and the generated water is distilled off while reducing the pressure as necessary. Thus, a polyester having a hydroxyl group is obtained. Next, this is reacted with polyisocyanate (3) at 40 to 140 ° C. to obtain a prepolymer (A) having an isocyanate group. Further, (A) is reacted with amines (B) at 0 to 140 ° C. to obtain a polyester modified with a urea bond. When (3) is reacted and (A) and (B) are reacted, a solvent can be used as necessary. Usable solvents include aromatic solvents (toluene, xylene, etc.); ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.); esters (ethyl acetate, etc.); amides (dimethylformamide, dimethylacetamide, etc.) and ethers And those inert to the isocyanate (3), such as tetrahydrofuran (such as tetrahydrofuran). When the polyester (ii) not modified with a urea bond is used in combination, (ii) is produced in the same manner as the polyester having a hydroxyl group, and this is dissolved in the solution after completion of the reaction of (i) and mixed. .

  In order to lower the viscosity of the oil phase of the toner composition and make it emulsifiable, a volatile solvent in which the modified polyester (i) or the prepolymer (A) is soluble is used. The solvent is preferably volatile with a boiling point of less than 100 ° C. from the viewpoint of easy removal. Examples of the solvent include toluene, xylene, benzene, carbon tetrachloride, methylene chloride, 1,2-dichloroethane, 1,1,2-trichloroethane, trichloroethylene, chloroform, monochlorobenzene, dichloroethylidene, methyl acetate, ethyl acetate, Methyl ethyl ketone, methyl isobutyl ketone and the like can be used alone or in combination of two or more. In particular, aromatic solvents such as toluene and xylene and halogenated hydrocarbons such as methylene chloride, 1,2-dichloroethane, chloroform, and carbon tetrachloride are preferable. In addition, the toner shape can be further adjusted by using a solvent that can be dissolved in an aqueous medium such as alcohol or water. The amount of solvent used with respect to 100 parts of the toner composition is usually 10 to 900 parts.

  As the dispersion of the toner composition, a homogenizer having a high-speed rotating body and a stator, a high-pressure homogenizer, and a disperser using a dispersing medium such as a ball mill, a bead mill, and a sand mill are preferable. Stirring may be used.

(Emulsification)
Although it does not specifically limit as a method of emulsification, What has a rotary blade is preferable. Any commercially available emulsifier and disperser can be used. For example, Ultra Turrax (manufactured by IKA), Polytron (manufactured by Kinematica), TK auto homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.), Ebara Milder (manufactured by Ebara Corporation), TK pipeline homomixer , TK homomic line flow (manufactured by Special Machine Industries Co., Ltd.), colloid mill (manufactured by Shinko Pantech Co., Ltd.), slasher, trigonal wet pulverizer (manufactured by Mitsui Miike Chemical Co., Ltd.), Cavitron (Eurotech Co., Ltd.) ), Fine flow mill (manufactured by Taiheiyo Kiko Co., Ltd.), and other continuous emulsifiers, CLEARMIX (manufactured by M Technique Co., Ltd.), fill mix (manufactured by Koki Kogyo Co., Ltd.), etc. Etc.

  The prepolymer (A) is preliminarily emulsified with another toner composition (hereinafter referred to as “toner raw material”) that has been mixed with a colorant, a colorant masterbatch, a release agent, a charge control agent, an unmodified polyester resin, and the like. It is preferable to mix in the pipe immediately before using a static mixer.

  When a dispersant is used, the dispersant can remain on the surface of the toner particles. However, after the elongation and / or cross-linking reaction, it is better to dissolve and wash away the remaining solid fine particle dispersant. From the aspect, it is preferable.

  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.

(Unnecessary removal)
In order to remove the organic solvent from the obtained emulsified dispersion, a method in which the temperature of the entire system is gradually raised to completely evaporate and remove the organic solvent in the droplets can be employed. In that case, it is preferable to carry out under reduced pressure because the heating temperature can be lowered. This is to prevent the wax and other toner constituents from dissolving in the organic solvent, and to prevent abnormal aggregation, association and coalescence due to heating of the emulsified dispersion. This organic solvent removal step may be performed before the aggregation step or after the aggregation step. If the organic solvent is removed before the aggregation step, fusion and coalescence of the fine particles after aggregation can be promoted.

  Another treatment method for those dissolved in an organic solvent is to spray the emulsified dispersion into a dry atmosphere to completely remove the water-insoluble organic solvent in the droplets to form toner fine particles, which are combined with an aqueous dispersion. It is also possible to evaporate and remove the agent. 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, in particular, various air currents heated to a temperature equal to or higher than the boiling point of the highest boiling solvent used is generally used. Sufficient quality can be obtained with a short treatment such as spray dryer, belt dryer or rotary kiln.

  As the agglomeration method, when fine particles are dispersed in water with an electric charge, the electric double layer is compressed by casting an electrolyte or the like to agglomerate the particles or form a high molecular weight water-soluble polymer into particles. By adsorbing and aggregating each other, or introducing a substance that is oppositely charged to the surfactant or dispersant used, the charge on the surface of the fine particles is neutralized and aggregated, or the adsorbed surfactant or dispersion A method is adopted in which the solubility of the surfactant or dispersant in the aqueous medium is changed by changing the counter ion of the agent or by introducing another substance into the aqueous medium to weaken the dispersion stability and cause aggregation. The

  At that time, it is agglomerated with the wax emulsion and the resin fine particles having the polar group described above to give the manufactured toner releasability at the time of fixing, to enhance the triboelectric chargeability, By disposing the high resin fine particles relatively outside the toner, blocking of the toners during high temperature storage can be prevented.

  Examples of the flocculant used include sodium sulfate, ammonium sulfate, potassium sulfate, magnesium sulfate, sodium phosphate, sodium dihydrogen phosphate, disodium hydrogen phosphate, ammonium chloride, calcium chloride, cobalt chloride, and strontium chloride. General inorganic or organic water-soluble salts represented by cesium chloride, barium chloride, nickel chloride, magnesium chloride, rubidium chloride, sodium chloride, potassium chloride, sodium acetate, ammonium acetate, potassium acetate, sodium benzoate, etc. Can be used.

  The concentration of these electrolytes is 0.01 to 2.0 mol / l (M) when a monovalent electrolyte is used, further 0.1 to 1.0 mol / l, and further 0.2 to 0.8 mol / l. The range of is preferable. Furthermore, when a polyvalent electrolyte is used, the amount added may be smaller. In the case of a surfactant, those exemplified above, and in the case of a polymer-based aggregating agent, among those that form the above-mentioned polymer protective colloid, those of ultra high molecular weight are particularly suitable. In addition, as a substance that coexists in an aqueous medium to weaken dispersion stability, it is possible to use water-soluble organic compounds such as ethanol, butanol, isopropanol, ethyl cellosolve, butyl cellosolve, dioxane, tetrahydrofuran, acetone, and methyl ethyl ketone. it can.

  Further, by heating the dispersion liquid after aggregation, the fine particles can be fused to adjust the shape of the toner to be produced. The particles are spheroidized by the interfacial tension, and the particle shape can be arbitrarily adjusted from spherical to indeterminate depending on the heating temperature, the viscosity of the toner, the presence of an organic solvent, and the like.

  The obtained dispersion of aggregated particles is sprayed in a dry atmosphere to completely remove the water-insoluble organic solvent remaining in the aggregated particles to form toner fine particles, and the aqueous dispersant is evaporated together. It is also possible to remove it. As the dry atmosphere in which the dispersion of the aggregated particles is sprayed, a gas obtained by heating air, nitrogen, carbon dioxide gas, combustion gas, etc., especially various air currents heated to a temperature higher than the boiling point of the highest boiling solvent used are generally used. It is done. Sufficient quality can be obtained with a short treatment such as spray dryer, belt dryer or rotary kiln. If the operation of re-dispersing (reslurry) is repeated by separating the liquid into solid and liquid before drying and redispersing (reslurry), the used dispersant and emulsifier can be almost removed.

  In addition, when an acid such as calcium phosphate salt or an alkali-soluble one is used as the dispersion stabilizer, the calcium phosphate salt is removed from the fine particles by a method such as washing with water after dissolving the calcium phosphate salt with an acid such as hydrochloric acid. To do. It can also be removed by operations such as enzymatic degradation.

(Classification)
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.

(Deformation)
To further adjust the shape of the obtained toner, a toner binder, a method of adjusting the shape mechanically using a hybridizer, mechanofusion, etc. A so-called spray drying method is a method in which a toner material is dissolved and dispersed in a solvent in which a toner binder is soluble, and then a solvent is removed using a spray drying apparatus to obtain a spherical toner. Moreover, although the method of making it spherical by heating in an aqueous medium is mentioned, it is not limited to this.

(External additive)
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 used. The primary particle diameter of the inorganic fine particles is preferably 5 mμ to 2 μm, and 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 use ratio of the inorganic fine particles 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.

  In addition, polymer fine particles, such as polystyrene obtained by soap-free emulsion polymerization, suspension polymerization, and dispersion polymerization, methacrylic acid ester, acrylic acid ester copolymer, polycondensation system such as silicone, benzoguanamine, nylon, thermosetting Examples thereof include polymer particles made of a resin.

  Such a fluidizing agent performs surface treatment to increase hydrophobicity, and can prevent deterioration of fluidity characteristics and charging characteristics even under high humidity. For example, silane coupling agents, silylating agents, silane coupling agents having an alkyl fluoride group, organic titanate coupling agents, aluminum coupling agents, silicone oils, modified silicone oils and the like are preferable surface treatment agents. .

  Examples of the cleaning property improver for removing the developer after transfer remaining on the photoreceptor or the primary transfer medium include, for example, zinc stearate, calcium stearate, fatty acid metal salts such as stearic acid, such as polymethyl methacrylate fine particles, polystyrene fine particles, etc. And polymer fine particles produced by soap-free emulsion polymerization. The polymer fine particles preferably have a relatively narrow particle size distribution and a volume average particle size of 0.01 to 1 μm.

(Carrier for two components)
When the toner of this embodiment is used as 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 toners per 100 parts by weight of the carrier. Part by weight is preferred. 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 electrically conductive 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 embodiment can also be used as a one-component magnetic toner that does not use a carrier, or a non-magnetic toner.
A preferred aspect of the image forming toner of this embodiment is an image forming toner containing at least a binder resin and a colorant.

The so-called toner scattering is a phenomenon in which the toner is scattered on the developing sleeve due to the generation of the reversely charged toner or the weakly charged toner. If the coercive force of the toner is in the range of 2 to 15 kA / m, preferably 5 to 10 KA / m. In addition, since the carrier and the toner, and the developing sleeve and the toner are held, the reversely charged toner and the weakly charged toner do not scatter and are re-stirred in the developing unit, so that the toner without toner scattering and fogging can be obtained. It can also be done.
When the coercive force of the toner is less than 2 kA / m, toner scattering occurs because the coercive force is low. On the other hand, when the coercive force of the toner exceeds 15 kA / m, the coercive force between the carrier and the toner and between the developing sleeve and the toner is too strong, the developing ability is lowered, and the image density is insufficient. For the measurement of the magneto-magnetic characteristics, a magnetic measurement device BHU-60 manufactured by Riken Denshi Co., Ltd. was used, and when the magnetic field was swept up to a measurement magnetic field of 398 Am ² / kg in toner filled in a cell having an inner diameter of 7 mmφ and a height of 10 mm. From the history curve, the coercive force was obtained.

In this embodiment, the volume specific resistance of the toner is set to about 10.9 to 11.4 Log Ωcm, the dispersion state of the colorant and the like in the toner is adjusted, and the charging stability of the toner, the toner scattering and the fog are adjusted. can do.
In the image forming toner of the present embodiment, a charge control agent can be blended in order to control chargeability.
Examples of the charge control agent in this case include a nigrosine dye, a quaternary ammonium salt, an amino group-containing polymer, a metal-containing azo dye, a salicylic acid complex compound, and a phenol compound. Among them, zirconium and aromatic oxy By using a zirconium compound composed of a carboxylic acid or a salt thereof, a toner having good charging stability and start-up property can be obtained.
Further, the toner may contain a wax, and it is effective for hot offset resistance to contain 0.5 to 7% by mass of carnauba wax and / or rice wax and / or ester wax as a wax component.

  In addition, as a carrier used as a two-component developer by mixing the image forming toner of the present embodiment, the main component is glass, iron, ferrite, nickel, zircon, silica, etc., and the particle size is about 30 to 1000 μm. It can be used by selecting from powders or those coated with styrene-acrylic resin, silicon resin, polyamide resin, polyvinylidene fluoride resin, etc., using this powder as a core material. A particle size of 30-80 μm is preferred.

  The image forming toner of this embodiment is filled in a container, and the container filled with the toner is distributed separately from the image forming apparatus, and a user can attach the image forming apparatus to the image forming apparatus to form an image. The container is not limited to be used. For example, a conventional bottle type or cartridge or a flexible cartridge capable of volume reduction is used.

  Further, the image forming method of the present embodiment includes a charging step of applying a voltage to the charging member from the outside to charge the charged body, a step of forming an electrostatic charge image on the charged charged body, an electrostatic charge Developing the image with toner and forming a toner image; Transfer process for applying a voltage to the transfer member from the outside to transfer the toner image onto the transfer member; Cleaning the surface of the charged object after transfer with a cleaning member A cleaning process for fixing the toner image, and a fixing process for fixing the toner image by heating. Specifically, the toner is used when an image is formed by using an apparatus for forming an image by electrophotography, and any apparatus other than such an apparatus can be used as long as it is an electrophotographic system. For example, a copying machine or a printer is included.

  For example, FIG. 2 shows an example of an image forming apparatus used in this embodiment. An image forming apparatus, which is a digital copying machine, uses a known electrophotographic system and includes a drum-shaped photosensitive member (1) therein. Around the photoreceptor (1), a charger (2) for carrying out an electrophotographic copying process along the rotation direction indicated by an arrow A, an exposure unit (3), a developing unit (4), a transfer unit (5), A cleaning unit (6), a recycling unit (15), and a fixing unit (10) are arranged.

The exposure unit (3) forms an electrostatic latent image on the photoreceptor (1) based on the image signal read by the reading unit (8) from the document placed on the document table (7) on the upper surface of the copying machine. To do.
The electrostatic latent image formed on the photoreceptor (1) is converted into a toner image by the developing unit (4), and the toner image is transferred to the transfer paper (5) fed from the paper feeding device (9). ) Is electrostatically transferred. The transfer paper on which the toner image is placed is conveyed and fixed to the fixing unit (10), and then discharged outside the apparatus.

  On the other hand, the untransferred portion and the contaminated photoreceptor (1) are cleaned by the cleaning portion (6), and the toner recovered by the cleaning is recovered to the toner hopper portion by the recycling means (15) and mixed with the replenishing toner. Then, the developer container is returned to the next image forming step.

  Furthermore, in order to reduce the generation of ozone in recent years, the contact method is effectively used in the charging process, the transfer process, and the cleaning process, and a charging roller, a charging blade, a transfer belt, a cleaning blade, and the like are used.

  In the recycling system, the toner of the present embodiment can prevent aggregation of the recycled toner due to the hardness of a minute metal material. The material of the charging roller, charging blade, transfer belt, and cleaning blade is preferably conductive rubber.

The fixing step is a fixing device that heat-fixes the toner image by passing a support holding the toner image between two rollers, and the thickness of the fixing roller on the side in contact with the toner image support surface However, it may be used for a fixing device in which a surface pressure (roller load / contact area) applied between two rollers is 1.5 × 10 ⁵ Pa or less, for example, 1.0 mm or less. The fixing roller used in the fixing process is made of RTV, silicon rubber, tetrafluoroethylene-perfluoroalkyl vinyl ether (PFA), poly-polyethylene on the surface of a metal cylinder composed of a high thermal conductor such as aluminum, iron, stainless steel or brass. An anti-offset layer such as tetrafluoroethylene (PTFE) is coated. A heating lamp is disposed inside the fixing roller. The metal cylinder of the pressure roller is often made of the same material as that of the fixing roller, and the surface thereof may be covered with an offset prevention layer such as PFA or PTFA. In addition, although not necessarily required, a heating lamp may be disposed inside the pressure roller.

  Although the fixing roller and the pressure roller are not shown, they are pressed against and rotated by springs at both ends. Fixing can be performed by passing a toner image adhesion support (transfer paper such as paper) between the fixing roller and the pressure roller.

The fixing device used in this embodiment may have an improved temperature rise characteristic of the fixing roller by setting the thickness of the metal cylinder of the fixing roller to 1.0 mm or less. Can be launched.
For example, although the thickness of a metal cylinder changes with the intensity | strength of a material to be used and heat conductivity, it is good also as 0.2-0.7 mm.

Further, the load (surface pressure) applied between the fixing roller and the pressure roller may be, for example, 1.5 × 10 ⁵ Pa or less. The surface pressure is a value obtained by dividing the load applied to both ends of the roller by the roller contact area.
The roller contact area is determined by passing a sheet whose surface property greatly changes due to heating, such as OHP paper, between the rollers heated to the fixing temperature, stopping on the way, holding it for several tens of seconds, and then discharging it. Find the area of the location.

As described above, a higher surface pressure is advantageous for fixing a toner image. However, in a fixing device in which the thickness of the metal cylinder of the fixing roller is 1.0 mm or less, a large load is applied because the roller is distorted. The load may be 1.5 × 10 ⁵ Pa or less, and further 0.5 to 1.0 × 10 ⁵ Pa.

  In this embodiment, a process cartridge that uses the toner of the present invention, integrally supports a photosensitive member and at least one part selected from a charging unit, a developing unit, and a cleaning unit, and is detachable from an image forming apparatus main body. It is good.

  In the present embodiment, at least one unit selected from a photosensitive unit, a charging unit, a developing unit, and a cleaning unit is integrally coupled as a process cartridge, and the process cartridge is configured as an image forming apparatus such as a copying machine or a printer. It can also be configured to be detachable from the main body. In FIG. 2, an image forming apparatus of one color is illustrated. However, in the present invention, it is a matter of course that a color (for example, four colors) image forming apparatus may be used. It was just something that was made to become.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further, this invention is not limited to these. Hereinafter, a part shows a weight part.

[Example 1]
<Oil phase 1>
[Low molecular polyester 1]
229 parts of bisphenol A ethylene oxide 2-mole adduct, 529 parts of terephthalic acid and 2 parts of dibutyltin oxide are placed in a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen introduction tube, and polycondensed at 230 ° C. for 8 hours at normal pressure. After reacting and further reacting under reduced pressure of 10 to 15 mmHg for 5 hours, 44 parts of trimellitic anhydride was put in a reaction vessel and reacted at 180 ° C. at normal temperature and normal pressure for 2 hours to obtain [Low molecular weight polyester 1].

[Masterbatch 1]
Add 1200 parts of water, 540 parts of carbon black (made by Printex35 Dexa) [DBP oil absorption = 42 ml / 100 mg, pH = 9.5], 1200 parts of polyester resin, mix with Henschel mixer (made by Mitsui Mining Co., Ltd.), and mix the two After kneading for 30 minutes at 150 ° C. using a roll, the product was cooled by rolling and pulverized with a pulverizer to obtain [Masterbatch 1].

[Ketimine Compound 1]
In a reaction vessel equipped with a stirrer 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].

  In a container equipped with a stir bar and thermometer, 380 parts of [Low molecular polyester 1], 110 parts of carnauba wax, 20 parts of a charge control agent (salicylic acid metal complex E-84: Orient Chemical Industry), and 950 parts of ethyl acetate are charged. The mixture was kept at 80 ° C. with stirring for 5 hours, and then cooled to 30 ° C. in 1 hour.

Next, 500 parts of [Masterbatch 1] and 500 parts of ethyl acetate were placed in a container and mixed for 2 hours to obtain [Raw material solution 1].
[Raw material solution 1] 1324 parts were transferred to a container, and using a bead mill (Ultra Visco Mill, manufactured by IMEX), a liquid feed speed of 1 kg / h, a peripheral speed of 6 m / sec, and 0.5 mm zirconia beads were filled at 80% by deposition. Dispersion was performed under pass conditions. Thereafter, 1324 parts of a 68% ethyl acetate solution of [low molecular weight polyester 1] was added, and one pass was performed with a bead mill under the conditions to obtain [masterbatch wax dispersion 1]. The solid content concentration of [Masterbatch wax dispersion 1] was 50%.
[Oil phase A] is obtained by mixing 750 parts of [Masterbatch wax dispersion 1] and 3.0 parts of [ketimine compound 1] with a homodisper (specialized machine) at 5000 rpm for 1 minute.

<Oil phase 2>
724 parts of bisphenol A ethylene oxide 2-mole adduct, 276 parts of terephthalic acid and 2 parts of dibutyltin oxide are placed in a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen introduction tube, and polycondensed at 230 ° C. for 8 hours at normal pressure. The reaction was further carried out at a reduced pressure of 10 to 15 mmHg for 5 hours to obtain [Polyester 1]. Next, 400 parts of [Polyester 1], 90 parts of isophorone diisocyanate and 500 parts of ethyl acetate were added and reacted at 100 ° C. for 5 hours to obtain <oil phase 2>.

<Water phase 1>
[Fine particle dispersion 1]
In a reaction vessel equipped with a stir bar and a thermometer, water 683 parts, sodium salt of methacrylic acid ethylene oxide adduct sulfate (Eleminol RS-30 Sanyo Chemical Industries), 83 parts of styrene, 83 parts of methacrylic acid, acrylic 110 parts of butyl acid and 1 part of ammonium persulfate were charged and stirred at 400 rpm for 15 minutes to obtain a white emulsion. The system temperature was raised to 75 ° C. and the reaction was allowed to proceed 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. Aqueous vinyl resin (a copolymer of styrene-methacrylic acid-butyl acrylate-methacrylic acid ethylene oxide adduct sulfate sodium salt). A dispersion [fine particle dispersion 1] was obtained. [Particulate dispersion 1] 83 parts of water, 990 parts of water and 90 parts of ethyl acetate were mixed and stirred to obtain <aqueous phase 1>.

  <Oil Phase 1> 60 parts, <Oil Phase 2> 8 parts, <Aqueous Phase 1> 100 parts, and a dispersing agent are introduced into the continuous emulsifying apparatus shown in FIG. A liquid feed amount (dispersing agent: sodium dodecyl diphenyl ether disulfonate aqueous solution (Eleminol MON-7 manufactured by Sanyo Chemical Industries, Ltd.) was adjusted with a pump so as to be 5.0% of the water phase liquid feed amount, and emulsification was performed. The solid content concentration when the dispersant was mixed with the aqueous phase was 6.8%.

  Then, unnecessary portions were removed by the following method. The temperature was raised to 45 ° C., and the solvent was removed at a stirring blade peripheral speed of 10 m / s and atmospheric pressure over 18 hours. Thereafter, the base particles were obtained after filtration, washing and drying.

  Next, 100 parts of the base particles were mixed with 0.5 part of hydrophobic silica and 0.5 part of hydrophobic titanium oxide using a Henschel mixer to obtain the toner of the present invention.

[Example 2]
The toner of the present invention was obtained in the same manner as in Example 1 except that the amount of the dispersant supplied was 9.0% of the amount of the aqueous phase supplied. At this time, the solid content concentration when the aqueous phase and the dispersant were mixed was 10.0%.

[Example 3]
The toner of the present invention was obtained in the same manner as in Example 1 except that the amount of the dispersant delivered was 3.0% of the amount of the aqueous phase delivered. The solid content concentration when the aqueous phase and the dispersant were mixed was 3.7%.

[Example 4]
The toner of the present invention was obtained in the same manner as in Example 1 except that the amount of the dispersant delivered was 9.5% of the amount of the aqueous phase delivered. At this time, the solid content concentration when the aqueous phase and the dispersant were mixed was 14.4%.

[Comparative Example 1]
The toner of the present invention was obtained in the same manner as in Example 1 except that the amount of the dispersant delivered was 10.5% of the amount of the aqueous phase delivered. At this time, the solid content concentration when the aqueous phase and the dispersant were mixed was 11.4%.

[Comparative Example 2]
The toner of the present invention was obtained in the same manner as in Example 1 except that the amount of the dispersant delivered was 0.5% of the amount of the aqueous phase delivered. The solid content concentration when the aqueous phase and the dispersant were mixed was 1.8%.

[Comparative Example 3]
A toner of the present invention was obtained in the same manner as in Example 1 except that the amount of the dispersant delivered was 14.0% of the amount of the aqueous phase delivered. The solid content concentration when the aqueous phase and the dispersant were mixed was 15.9%.

[Particle size distribution measurement]
For the average particle size and particle size distribution of the toner, Coulter Multisizer III (manufactured by Coulter Inc.) was used. The sample was dispersed in the suspended electrolyte for about 3 minutes with an ultrasonic disperser, and the volume and number of toners of 2 μm or more were measured 50,000 counts using a 100 μm aperture tube, and the volume distribution (Dv) and number were measured. Distribution (Dn) was calculated. The closer Dv / Dn is to 1.0, the sharper the distribution.

[Image evaluation]
In the image evaluation, fine line reproducibility was evaluated in five stages, and a large number was evaluated as good.
For fine line reproducibility, each toner obtained above was mixed at a ratio of 8 g to 100 g of ferrite carrier to make a developer, and the fixing oil portion of an intermediate transfer type color copier (Imagio 5000 manufactured by Ricoh Co., Ltd.) was used. Put it in the removed evaluation machine and run it using plain paper (Type 6000 made by Ricoh Co., Ltd.) with a printing rate of 7% image occupancy, and the fine line part of the initial 10th image and the 20000th image at that time In comparison with the manuscript, it was observed with an optical microscope and evaluated.

  As shown by the test results in Table 1 below, by adjusting the amount of the dispersant to an appropriate amount according to the present invention, the particle size can be controlled, so that use of useless raw materials can be suppressed. Further, since particles having a sharp particle size distribution are obtained, it can be seen that a high-quality image can be obtained when the final toner is obtained.

  From the above description, in the present embodiment, the dispersant is added during mixing of the aqueous phase and mixed in the pipe, so that the dispersant can be added in an arbitrary amount rather than being charged all at once. Therefore, the particle size can be adjusted in real time, and a desired particle size distribution can be obtained.

  Further, the amount of dispersant added during the feeding of the aqueous phase is 1.0% to 10.0% as the dispersing agent feeding amount relative to the aqueous phase feeding amount, or the solid content concentration when mixed with the aqueous phase Is 4.0% to 15.0, a toner having a small particle size and a sharp particle size distribution can be produced.

  In addition, since the toner has a small particle size with a Dv of 4.0 μm to 8.0 μm, a Dv / Dn of 1.05 to 1.20, and a sharp particle size distribution according to the above manufacturing method, an image with high image quality is obtained. Can be formed.

It is a figure which shows an example of the continuous emulsification apparatus used with the manufacturing method of the toner of this invention. It is a figure which shows an example of the image forming apparatus used for this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Photoconductor 2 Charging device 3 Exposure part 4 Developing part 5 Transfer part 5a Transfer belt 6 Cleaning part 6a Cleaning blade 6b Cleaning brush 7 Document placement stand 8 Reading part 9 Paper feeder 10 Fixing part 14 Waste toner tank 15 Recycling part 21 Fixing Roller 22 Pressure roller 23 Metal cylinder 24 Offset prevention layer 25 Heating lamp 26 Metal cylinder 27 Offset prevention layer 28 Heating lamp

Claims (3)

A solution and / or dispersion obtained by dissolving or dispersing at least a resin, a colorant and a release agent in an organic solvent or an organic dispersant, and an aqueous medium containing a solid fine particle dispersant that is hardly soluble in water are continuously added. A method for producing a toner in which particles are taken out by removing an organic solvent or an organic dispersant before and / or after agglomeration and dispersion to a toner size by feeding to an emulsifier,
After adding a surfactant in the middle of liquid feeding of the aqueous medium and mixing in a static mixer, it is fed to the emulsifier,
A method for producing an electrophotographic toner, wherein the amount of the surfactant to be fed is 1.0% by mass to 10.0% by mass with respect to the amount of the aqueous medium to be fed . 2. The electrophotographic apparatus according to claim 1, wherein the concentration of the resin component contained in the liquid when the surfactant and the aqueous medium are mixed in a static mixer is 4.0% by mass to 15.0% by mass. Toner manufacturing method. The volume average particle diameter (Dv) of the toner is 4.0 μm to 8.0 μm, and the volume average particle diameter (Dv) / number average particle diameter (Dn) of the toner is 1.05 to 1.20. The method for producing an electrophotographic toner according to claim 1.

Images