JP4769607B2 - Toner, image forming apparatus, and process cartridge - Google Patents

Description

  The present invention relates to a toner, an image forming apparatus, and a process cartridge.

  In recent years, needs for environmentally friendly, small and inexpensive personal use copiers and laser printers have increased. In response to such demands for environmental friendliness, miniaturization, and cost reduction, recently, it has been studied to use contact charging means without using a corona discharger. Specifically, while applying a voltage to the conductive roller / brush as a charging member, it is brought into contact with a charged body such as a photoconductor to charge the surface of the charged body to a predetermined potential. If such contact charging means is used, the unit can be simplified, miniaturized, and the voltage can be reduced as compared with the corona discharger, and the amount of ozone generated can be reduced.

  On the other hand, in the contact charging device, a DC voltage or a DC voltage superposed with an AC voltage is applied to the charging member. At this time, in the vicinity of the contact portion between the charging member and the photosensitive drum, the abnormal charging and flying motion of the residual toner having a small particle size and light weight are repeated. For this reason, there is a situation where residual toner is easily electrostatically attracted or embedded in the surface of the charging member or the photosensitive drum, and the contact charging means is very different from the case of using the non-contact charging means by the conventional corona discharger. The charging performance tends to change with time.

  Also, due to similar market needs, recently, a fixing mechanism for a color copying machine or a color laser printer using an oilless fixing device has been rapidly spread.

  By making the fixing mechanism of the color output machine oil-free, the fixing device can be simplified, and since oil is not consumed as a consumable item, it is effective in reducing running costs.

  The toner used in such an oilless color image fixing apparatus must have gloss to obtain a preferable color image while improving the release function. It is difficult to achieve both, and it is a conflicting characteristic item.

  In recent years, attempts have been made to formulate and manufacture various toners against these conflicting properties. In toners using the pulverization method, both the conflicting properties can be achieved by designing the resin and wax materials and the wax domain dispersion technology. There are many attempts to plan. In addition, in the toner by the polymerization method or the wet granulation method, it is possible to relatively increase the wax content from the manufacturing principle as compared with the toner by the pulverization method. Since it is also possible to control the position of the toner, recently, as a toner method suitable for oilless fixing, a method development and a prescription development have been very active.

  However, in general, a toner highly filled with wax has a problem that the wax on the surface is liberated and image noise is generated in processes other than fixing. In particular, when free wax is filmed on the developer carrier or latent image carrier in the developing section, problems such as charging failure occur, causing image noise such as fogging, and further, filling the latent image carrier. There is a problem that the wax that has been mingled is transferred to the contact charging member, the charging ability is lowered, and charging of the latent image carrier is caused.

  Furthermore, in the case of a toner by a polymerization method, since it is generally produced by granulation in an aqueous system, the charging performance of the toner base particles is higher than that of a toner by a pulverization method due to the influence of a surfactant added during the production. Therefore, there is a problem that image noise such as fog is easily deteriorated.

  In addition, as described above, when the toner is highly filled with wax, it is difficult to disperse the wax when it is manufactured by a pulverization method, so that the distribution of the dispersed particle diameter of the wax is likely to be wide, and free wax is also generated. The toner composition tends to be non-uniform. As a result, the charge distribution of the toner becomes broad, and the problem of image noise such as fogging due to poorly charged toner becomes significant.

  Further, as a problem caused by such wax dispersion, toner powder cohesiveness is deteriorated. As a result, transferability is deteriorated, and problems such as omission of characters and fine lines occur.

  As a means for suppressing such filming of oilless fixing color toner members, the formulation of toner base particles and filming that suppress the release of wax and other toner additives that cause filming Measures such as external addition of an abrasive substance to the surface of toner particles to remove the substance and external addition of a lubricating substance to make the filming substance difficult to adhere to the member are being studied.

  As a polishing agent for removing the filming substance, a method of adding hard inorganic fine particles of several hundred nanometers has been conventionally disclosed. For example, in Patent Document 1, by adding cerium oxide as a polishing agent. There is a description that the filming substance can be effectively removed. Patent Document 2 describes that the filming substance can be effectively removed by adding strontium titanate particles having a particle size range of 200 to 800 nm.

  However, although these means have a high effect of removing the filming substance on the photosensitive member having the cleaning blade, in general, a member such as a contact charging roller having no friction member such as a regulation blade or a cleaning blade is added. There is a problem that the abrasive that has been transferred to the contact charging member and the charging performance thereof is lowered. That is, the known abrasive material has a problem that it is poorly contaminated with respect to the charging member in the contact charging method.

  On the other hand, as a lubricant that makes it difficult to adhere a filming substance, generally, a method of adding metal soap is widely known, but this means is certainly high in suppressing filming on the photoconductor due to a lubricating effect. Although effective, there is a problem that the charging property is greatly changed due to charge-up of the toner and the charging stability is lowered.

  On the other hand, magnesium silicate minerals (attapulgite, sepiolite, etc.) disclosed in Patent Document 3 are effective for filming during cleaning, but have a high water content and cause poor charging even in normal use environments. Problems due to poor charging, such as background contamination, toner leakage, and toner scattering, are likely to occur.

  Similarly, when magnesium silicate treated with silicone oil disclosed in Patent Documents 4 to 6 is used, the toner fluidity deteriorates due to the silicone oil, the charge rises, etc., the conveyance failure in the developing device, the density is lowered. cause.

  In Patent Document 7, there is a description that a silicate fine powder is made of magnesium silicate, and a toner with a coverage of 60 to 100% is prepared. However, when used as a negatively charged toner, a reversely charged toner is likely to be generated, and scumming is likely to occur. . This is because, as shown by the relationship of electronegativity (see Non-Patent Document 1), magnesium silicate tends to be positively charged due to the influence of the MgO portion that tends to be strong positively charged.

  When the titanic acid fine powder is used as in the toner described in Patent Document 8, an excellent effect on filming is exhibited. However, since this material itself has a low resistance, a leakage of charging is large. Soil stains, toner leakage, and toner scattering are likely to occur. In addition, there is a problem that the charging performance of the charging member is lowered when the charging member is transferred.

  Even when titania is used as in the toner described in Patent Document 9, it is difficult to adjust the amount of addition because this material is a low-resistance and high-dielectric constant material. It is large and causes a decrease in charge of the entire toner, and a small amount causes an increase in charge. Thereby, in any case, scumming, toner leakage, and toner scattering are likely to occur.

As described above, in the full-color toner with high wax filling, the actual situation is that filming, chargeability, and member contamination are contradictory characteristics.
Japanese Patent No. 2656230 Japanese Patent No. 3407545 JP 2002-31913 A JP-A-3-294864 JP-A-4-214568 JP-A-5-165257 JP 11-95480 A JP-A-11-184239 JP 2003-186240 A Journal of the Imaging Society of Japan Vol.39 No.3 259

  In view of the above-described problems of the prior art, the present invention uses a toner having good chargeability and capable of suppressing adhesion to the surface of the charging member and the surface of the photosensitive member and generation of scratches, and the toner. An object is to provide an image forming apparatus and a process cartridge.

The invention according to claim 1 is a toner having colored particles containing a binder resin, a colorant and a release agent, and first inorganic particles, wherein the first inorganic particles have an average secondary particle size. Ru der above 2μm or less 0.02 [mu] m, a MgSiO ₂ particles or _Mg 2 SiO ₄ particles, relative to the first atomic concentration ratio of Mg to Si of the inorganic particles, Si in the vicinity of the surface of the first inorganic particles It is characterized by being larger than the atomic concentration ratio of Mg.

  According to a second aspect of the present invention, in the toner according to the first aspect, the first inorganic particles have an average primary particle size of 0.02 μm or more and 0.15 μm or less.

  The invention according to claim 3 is the toner according to claim 2, wherein the first inorganic particles are sintered aggregates having an average secondary particle size of 0.05 μm or more and 2 μm or less. To do.

  According to a fourth aspect of the present invention, in the toner according to any one of the first to third aspects, the first inorganic particles are externally added to the colored particles.

  According to a fifth aspect of the present invention, in the toner according to any one of the first to fourth aspects, the first inorganic particles are forsterite, enstatite, or steatite.

According to a sixth aspect of the present invention, in the toner according to any one of the first to fifth aspects, the first inorganic particles include Mg (OH) ₂ particles or MgO particles and an average primary particle size of 0. .. Sintered SiO ₂ particles having a size of 10 μm or less, and then obtained by acid treatment .

  The invention according to claim 7 is the toner according to any one of claims 1 to 6, wherein the average primary particle size is 5 nm or more and 20 nm or less, and second inorganic particles made of hydrophobic silica; The average primary particle size is 20 nm or more and 100 nm or less, and further has third inorganic particles made of hydrophobic titania or hydrophobic silica.

  According to an eighth aspect of the present invention, in the toner according to the seventh aspect, the ratio of the total weight of the second inorganic particles and the third inorganic particles to the weight of the colored particles is 2% or more and 5% or less. The ratio of the weight of the first inorganic particles to the weight of the colored particles is from 0.3% to 5%.

  The invention according to claim 9 is the toner according to claim 7 or 8, wherein the weight ratio of the second inorganic particles to the third inorganic particles is 1/9 or more and 7/3 or less. Features.

The invention according to claim 10, in the toner according to any one of claims 1 to 9, prior Symbol colored particles is a volume average particle diameter of 4μm or more 9μm or less, the non-magnetic one-component developing method It is used.

The invention according to claim 11, in the toner according to any one of claims 1 to 9, prior Symbol colored particles is a volume average particle diameter of 4μm or more 9μm or less, used in two-component developing method It is characterized by that.

  According to a twelfth aspect of the present invention, in the toner according to any one of the first to eleventh aspects, the colored particles contain 3.5% by weight or more and 10% by weight of the release agent, and are pulverized. It is manufactured by.

  According to a thirteenth aspect of the present invention, in the toner according to any one of the first to eleventh aspects, the colored particles contain the release agent in an amount of 5 wt% to 12 wt%, and wet granulation It is manufactured by the method.

Invention of claim 14, conveying and pivotable image bearing member, disposed in contact with said image bearing member, a charging member Ru charges the image bearing member to a predetermined potential, the toner by rotating in the image forming apparatus having a developing device having a supply member for supplying the conveying member and the toner on the conveying member, the toner is characterized in that a toner according to any one of claims 1 to 13 .

The invention according to claim 15, an image bearing member, an electrostatic latent image formed on the image bearing member is developed with a toner developing device for forming a toner image is supported on one body, an image forming apparatus in universal process cartridge detachable to the main body, the toner is characterized in that a toner according to any one of claims 1 to 13.

  According to the present invention, there is provided a toner having good chargeability and capable of suppressing the adhesion to the surface of the charging member or the surface of the photoreceptor or the generation of scratches, and an image forming apparatus and a process cartridge using the toner. can do.

  Next, the best mode for carrying out the present invention will be described.

  The toner of the present invention has at least colored particles containing a binder resin, a colorant and a release agent, and at least one kind of inorganic particles, and the inorganic particles are preferably externally added to the colored particles. In addition, external addition means adding to the coloring particle | grains obtained previously so that it may exist on the surface (external) of coloring particle | grains.

The toner of the present invention has an average secondary particle size (number average) of 0.02 to 2 μm and a general formula Mg _x SiO _{x + 2} (x is 1 or 2).
It has the inorganic particle A represented by these. Here, when x = 1, the inorganic particle A corresponds to a material having a specific crystal structure called steatite or enstatite, and when x = 2, the inorganic particle A is a material having a specific crystal structure called forsterite. Applicable, both can be identified by analysis by X-ray diffraction.

In general, MgO · SiO ₂ composite oxides called forsterite, steatite, and enstatite have properties similar to alumina, such as high thermal expansion, and are also excellent in dielectric properties in the high frequency region and insulation resistance at high temperatures. It is a material with characteristics and has been used as ceramics for electronic parts since ancient times.

However, since the conventional MgO.SiO ₂ composite oxide powder has a small average primary particle size (number average), it exceeds 0.2 μm, and the average secondary particle size (number average) is 2 to 3 μm or more. When added to an electrophotographic toner, there are problems such as poor dispersibility on the surface of the toner, adversely affecting the chargeability of the toner, and scratching the photoreceptor due to its large particle size. There is a problem in application to

The inorganic particles A of the present invention can solve the problem when such a conventional MgO.SiO ₂ composite oxide powder (magnesium silicate particles) is applied to a toner. That is, the conventional MgO.SiO ₂ composite oxide powder has a clearly small particle size distribution, and the fine particles having an average primary particle size (number average) of 0.02 to 0.15 μm are in the shape of grape tufts. It is preferable to form a sintered aggregate (secondary particle). Furthermore, the average secondary particle size (number average) is preferably 0.05 to 2.0 μm, more preferably 0.1 to 1.5 μm.

By using MgO / SiO ₂ composite oxide adjusted to such a particle size range, the problems of dispersibility on the toner surface and scratches on the members, which are the problems of the conventional magnesium silicate, are solved. Is possible.

The inorganic particles A having such a particle size distribution are sintered by mixing Mg (OH) ₂ powder or MgO powder and SiO ₂ powder having an average primary particle size (number average) of 0.10 μm or less. It is preferable that the inorganic particles A thus obtained are identified as forsterite, enstatite, or steatite by analysis by X-ray diffraction, and the inorganic particles A thus produced are unreacted MgO, Mg (OH ) _2, is preferably free of SiO _2.

  In the present invention, the inorganic particles A are surface-treated so that the Mg atomic concentration ratio Mg / Si ratio with respect to Si on the surface decreases. By performing such treatment, the charging characteristics of the surface of the inorganic particles A are shifted to the negatively charged side as compared with the case where the treatment is not performed, and the migration of the inorganic particles A to the positively charged contact charging mechanism is suppressed. In addition, deterioration with time of the contact charging function can be suppressed.

  Examples of such a treatment method include a method of treating the pH of the aqueous medium acidic in a wet process such as pulverization / disintegration in the production process of the inorganic particles A and a washing process. It is considered that this acid treatment partially destroys the crystal structure of the inorganic particles A, and the Mg / Si ratio on the surface is lowered by the elution of Mg first due to the difference in solubility between Mg and Si.

  When the Mg / Si ratio of the inorganic particles A is (a) and the Mg / Si ratio in the vicinity of the surface of the inorganic particles A is (a), the ratio of (a) to (a) (b) / (a) is It is preferable that it is 0.6-0.9. When (A) / (A) is larger than 0.9, the charging characteristics of the surface of the inorganic particles A may not be sufficiently transferred to the negative charging side. Moreover, when smaller than 0.6, destruction of the crystal structure of the inorganic particle A becomes large, and the electrical characteristics of the inorganic particle A may be impaired.

  In addition, (A) can be calculated from a value quantitatively analyzed by a method capable of analyzing the entire bulk of the inorganic particles A such as fluorescent X-ray analysis, and (A) can be calculated by X-ray photoelectron spectroscopy ( XPS) can be calculated from a value quantitatively analyzed by a method of analyzing only the outermost surface region having an analysis depth of several nanometers from the surface.

  By having such inorganic particles A, the toner of the present invention has the following excellent characteristics.

  First, filming (contamination) of a full color toner containing a large amount of a release agent and an external additive on a charging member and a photoreceptor can be eliminated. This is because the inorganic particles A contain the above-mentioned secondary particles, and therefore, during the blade cleaning, the inorganic particles A released from the toner form a damming layer at the blade nip portion, and the release mold is released through the blade nip portion. This is considered to be due to the function of reducing the amount of the agent. When the number average particle size of the inorganic particles A is smaller than 0.02 μm, the effect of preventing filming is insufficient, and when the number average particle size is larger than 2 μm, when repeated image formation is performed, during blade cleaning, or a full-color image forming apparatus, etc. Then, at the time of pressure transfer by the transfer drum or the intermediate transfer belt, the photoconductor is easily damaged.

  Secondly, there is almost no transfer to a charging member such as a charging roller in the contact charging method, and even if it is transferred, the electric resistance of the charging roller is reduced from the electric characteristics (high resistance and low dielectric constant) of the inorganic particles A. The charging performance of the charging roller is hardly deteriorated as a result.

  Third, since the inorganic particles A contain magnesium, the charge polarity is likely to have a positive polarity, and since the above-described relatively large secondary particles are used, when used in one-component development, the toner is used during development. Has a secondary effect of supplementing the negative chargeability of the toner when peeled from the toner, and when used in two-component development, the secondary effect of supplementing the positive chargeability of the carrier by the transfer of the inorganic particles A to the carrier As a result, the chargeability of the full-color toner for oilless fixing containing a large amount of a release agent and poor chargeability (charge distribution is broad) can be improved. Furthermore, a toner with poor chargeability obtained by wet granulation in an aqueous medium such as a polymerized toner can be used more effectively.

  In the present invention, the inorganic particles A are preferably added in an amount of 0.3 to 5.0% by weight, more preferably 0.5 to 3.0% by weight, based on the colored particles. When the addition amount is less than 0.3% by weight, the effect of preventing filming may be insufficient, and when the addition amount is more than 5% by weight, the influence on the chargeability of the toner may be increased.

The specific surface area of the inorganic particles A is usually 5 to 50 m ² / g, preferably 5 to 40 m ² / g.

  In addition, the inorganic particles A may be surface-treated with a hydrophobizing agent, an amino coupling agent, an amino silicone oil and the like which will be described later.

  The toner of the present invention preferably further includes inorganic particles B having a predetermined particle size and a predetermined degree of hydrophobicity, and inorganic particles C having a predetermined particle size.

  The inorganic particles B are made of hydrophobic silica having an average primary particle size (number average) of 5 to 20 nm, preferably 7 to 15 nm and a hydrophobization degree of 55 to 90. By using the inorganic particles B, it is possible to improve the fluidity of the toner to improve the gradation reproducibility and to impart lubricity to the photosensitive member of the cleaning blade. When the average primary particle size is larger than 20 nm, the effect of improving the fluidity of the toner and the effect of improving the lubricity of the cleaning blade may be insufficient. On the other hand, when the average particle size is smaller than 5 nm, embedding in colored particles is likely to occur, and the change in powder characteristics during printing durability may be increased, and environmental stability may be reduced.

  The inorganic particles C have an average primary particle size (number average) of 20 to 100 nm, preferably 25 to 80 nm, and are made of hydrophobic silica or hydrophobic titania having a degree of hydrophobicity of 55 to 90. By using the inorganic particles C, it is possible to suppress the occurrence of white spots in the transfer step in the full-color image forming method, particularly secondary transfer when using an intermediate transfer belt, and it is possible to improve heat-resistant storage stability. . When the average primary particle size is larger than 100 nm, the coverage with respect to the toner is decreased, and thus the environmental stability, heat-resistant storage property, and the effect of suppressing the occurrence of white spots may be reduced. Due to the agitation stress in the developing device at the time, the inorganic particles C tend to be embedded in the colored particles, and as a result, the effect of suppressing the aggregation of the developer is reduced and white spots occur in the solid image. May be easier. As the inorganic particles C, either silica or titania may be used. In particular, it is effective to use titania to suppress a decrease in image density due to charge-up in a low-temperature and low-humidity environment in the two-component development method. It is. Further, in order to adjust the fluctuation of the charging level and the charging environment, silica and titania may be appropriately used as the inorganic particles C. As titania, anatase titania, rutile titania, amorphous titania and the like can be used.

  The total amount of inorganic particles B and inorganic particles C added is preferably 2 to 5% by weight, more preferably 2 to 3.5% by weight, based on the colored particles. If the amount added is less than 2% by weight, the effect of suppressing the occurrence of white spots may be insufficient. If the amount added exceeds 5% by weight, filming on the charging member or latent image carrier by the free inorganic particles will occur. (Contamination) may occur easily. The weight ratio of the inorganic particles B to the inorganic particles C varies depending on the respective particle sizes and the like, but cannot be generally specified, but is preferably 1/9 to 7/3, and more preferably 1/4 to 3 / 2. When the weight ratio is larger than 7/3, it may be difficult to obtain the effect of improving transfer dropout. When the weight ratio is smaller than 1/9, the fluidity of the toner is remarkably deteriorated. Failure to form a thin layer on the roller is likely to occur.

  The inorganic particles B and the inorganic particles C are surface-treated with a hydrophobizing agent. As the hydrophobizing agent, silane coupling agents, titanate coupling agents, silicone oils, silicone varnishes and the like can be used. Examples of silane coupling agents include hexamethyldisilazane, trimethylsilane, trimethylchlorosilane, dimethyldichlorosilane, methyltrichlorosilane, allyldimethylchlorosilane, benzyldimethylchlorosilane, methyltrimethoxysilane, methyltriethoxysilane, and isobutyltrimethoxysilane. , Dimethyldimethoxysilane, dimethyldiethoxysilane, trimethylmethoxysilane, hydroxypropyltrimethoxysilane, phenyltrimethoxysilane, n-butyltrimethoxysilane, n-hexadecyltrimethoxysilane, n-octadecyltrimethoxysilane, vinyltrimethoxy Silane, vinyltriethoxysilane, γ-methacryloyloxypropyltrimethoxysilane, vinyltriacetoxysila Etc., and as the silicone oil, for example, dimethyl polysiloxane, methyl hydrogen polysiloxane, methyl phenyl polysiloxane.

  When the inorganic particles are surface-treated with the hydrophobizing agent, for example, a solution obtained by diluting the hydrophobizing agent with a solvent is added to the inorganic particles and mixed, and the resulting mixture is heated, dried, and then crushed. The method can be performed by a wet method in which inorganic particles are dispersed in an aqueous medium to form a slurry, a hydrophobizing agent is added and mixed, the mixture is heated and dried, and then crushed. In particular, for inorganic particles made of titania, it is preferable to perform the surface treatment in an aqueous medium from the viewpoints of uniformity of surface treatment, prevention of aggregation of inorganic particles, and the like.

  In the present invention, the degree of hydrophobicity can be measured by a methanol wettability method. First, methanol is dropped into water in which the sample is dispersed, and the weight of methanol necessary to wet the entire sample is measured. The ratio of the weight of methanol to the weight of the mixed solvent of water and methanol at this time is expressed in percentage as the degree of hydrophobicity.

  In the present invention, the colored particles contain at least a binder resin, a colorant, and a release agent.

  As the binder resin, resins known in the field of electrophotography, electrostatic printing, etc. can be used. For example, styrene resins, acrylic resins such as alkyl (meth) acrylate, styrene acrylic copolymer resins, polyester resins Resins, silicone resins, olefin resins, amide resins, epoxy resins, and the like can be used.

  In particular, when used in a full-color toner for oilless fixing, from the viewpoint of fixing separation and preferable image glossiness, a polymer elastic resin component (first binder resin) and a sharp melt low-molecular resin component (second binder resin) are used. ) Are preferably used in combination.

  The types of the first binder resin and the second binder resin are not particularly limited, and are known binder resins in the field of full color toners, for example, polyester resins, (meth) acrylic resins, styrene- (meth) acrylic copolymer weights. Examples include coalesced resins, epoxy resins, and COC (cyclic olefin resins (for example, TOPAS-COC (manufactured by Ticona))). From the viewpoint of oilless fixing, the first binder resin and the second binder resin are both polyesters. It is preferable to use a base resin.

  In the present invention, as the polyester resin, a polyester resin obtained by polycondensation of a polyhydric alcohol component and a polyvalent carboxylic acid component can be used.

  Among the polyhydric alcohol components, examples of the dihydric alcohol component include polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane and polyoxypropylene (3.3) -2,2. -Bis (4-hydroxyphenyl) propane, polyoxypropylene (6) -2,2-bis (4-hydroxyphenyl) propane, polyoxyethylene (2.0) -2,2-bis (4-hydroxyphenyl) Alkylene oxide adducts of bisphenol A such as propane; ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, neopentyl glycol, 1,4-butene Diol, 1,5-pentanediol, 1,6-hexanedio Le, 1,4-cyclohexanedimethanol, dipropylene glycol, polyethylene glycol, polytetramethylene glycol, bisphenol A, hydrogenated bisphenol A, and the like. Examples of the trivalent or higher alcohol component include sorbitol, 1,2,3,6-hexanetetrol, 1,4-sorbitan, pentaerythritol, dipentaerythritol, tripentaerythritol, 1,2,4-butanetriol. 1,2,5-pentanetriol, glycerol, 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, trimethylolpropane, 1,3,5-trihydroxymethylbenzene, etc. Is mentioned.

  Among the polyvalent carboxylic acid components, examples of the divalent carboxylic acid component include maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, phthalic acid, isophthalic acid, terephthalic acid, cyclohexanedicarboxylic acid, and succinic acid. Acid, adipic acid, sebacic acid, azelaic acid, malonic acid, n-dodecenyl succinic acid, isododecenyl succinic acid, n-dodecyl succinic acid, isododecyl succinic acid, n-octenyl succinic acid, isooctenyl succinic acid, n-octyl succinic acid Examples thereof include acids, isooctyl succinic acid, acid anhydrides or lower alkyl esters thereof. Examples of the trivalent or higher carboxylic acid component include 1,2,4-benzenetricarboxylic acid (trimellitic acid), 1,2,5-benzenetricarboxylic acid, 2,5,7-naphthalenetricarboxylic acid, 1,2 , 4-Naphthalenetricarboxylic acid, 1,2,4-butanetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, 1,3-dicarboxyl-2-methyl-2-methylenecarboxypropane, 1,2,4- Examples include cyclohexanetricarboxylic acid, tetra (methylenecarboxyl) methane, 1,2,7,8-octanetetracarboxylic acid, pyromellitic acid, empole trimer acid, anhydrides of these acids, and lower alkyl esters.

  In the present invention, the polyester resin is a mixture of a polyester resin raw material monomer, a vinyl resin raw material monomer, and a monomer that reacts with both resin raw material monomers. A resin obtained by performing the condensation polymerization reaction to be obtained and the radical polymerization reaction to obtain a vinyl resin in parallel (hereinafter referred to as vinyl polyester resin) can also be used. In addition, the monomer which reacts with the raw material monomer of both resin is a monomer which can be used for both reaction of a condensation polymerization reaction and a radical polymerization reaction in other words. That is, it is a monomer having a carboxyl group or hydroxyl group that can undergo a condensation polymerization reaction and a vinyl group that can undergo a radical polymerization reaction, and examples thereof include fumaric acid, maleic acid, acrylic acid, and methacrylic acid.

  Examples of the raw material monomer for the polyester resin include the polyhydric alcohol component and the polyvalent carboxylic acid component described above.

  Examples of the raw material monomer for the vinyl resin include styrene, o-methyl styrene, m-methyl styrene, p-methyl styrene, α-methyl styrene, p-ethyl styrene, 2,4-dimethyl styrene, p-tert. -Styrene or styrene derivatives such as butylstyrene and p-chlorostyrene; Ethylene unsaturated monoolefins such as ethylene, propylene, butylene and isobutylene; Methyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n- methacrylate Butyl, isobutyl methacrylate, t-butyl methacrylate, n-pentyl methacrylate, isopentyl methacrylate, neopentyl methacrylate, 3-methylbutyl methacrylate, hexyl methacrylate, octyl methacrylate, nonyl methacrylate, Alkyl methacrylates such as decyl crylate, undecyl methacrylate, dodecyl methacrylate; methyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, t-butyl acrylate, acrylic acid alkyl acrylates such as n-pentyl, isopentyl acrylate, neopentyl acrylate, 3-methylbutyl acrylate, hexyl acrylate, octyl acrylate, nonyl acrylate, decyl acrylate, undecyl acrylate, dodecyl acrylate; acrylic acid , Unsaturated carboxylic acids such as methacrylic acid, itaconic acid, maleic acid; acrylonitrile, maleic acid ester, itaconic acid ester, vinyl chloride, vinyl acetate, vinyl benzoate, vinyl methyl ethyl ketone, vinyl hex Examples include silketone, vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether.

  As a polymerization initiator when polymerizing the raw material monomer of the vinyl resin, for example, 2,2′-azobis (2,4-dimethylvaleronitrile), 2,2′-azobisisobutyronitrile, 1,1 Azo or diazo polymerization initiators such as' -azobis (cyclohexane-1-carbonitrile), 2,2'-azobis-4-methoxy-2,4-dimethylvaleronitrile, benzoyl peroxide, dicumyl peroxide, And peroxide polymerization initiators such as methyl ethyl ketone peroxide, isopropyl peroxycarbonate, lauroyl peroxide, and the like.

  As the first binder resin and the second binder resin, various polyester resins as described above are preferably used. Among them, from the viewpoint of further improving the separability and offset resistance as an oilless fixing toner, It is more preferable to use the first binder resin and the second binder resin shown in FIG.

  The first binder resin is preferably a polyester resin obtained by polycondensation of the above-described polyhydric alcohol component and polyhydric carboxylic acid component. As the polyhydric alcohol component, an alkylene oxide adduct of bisphenol A is used, and the polyhydric carboxylic acid is used. Polyester resins obtained using terephthalic acid and fumaric acid as components are particularly preferred.

  The second binder resin is preferably a vinyl-based polyester resin, and an alkylene oxide adduct of bisphenol A, terephthalic acid, trimellitic acid, and succinic acid are used as a raw material monomer for the polyester resin, and styrene and a raw material monomer for the vinyl-based resin are used. A vinyl polyester resin obtained by using butyl butyrate and fumaric acid as the both-reactive monomer is particularly preferred.

  In the present invention, in order to increase the amount of a release agent necessary for oilless color fixing, it is preferable to add a release agent in advance to the binder resin. In this case, the toner may be internally added to either the first binder resin or the second binder resin. However, in the case of the toner by the pulverization method, it is preferable to internally add to the first binder resin from the viewpoint of easily taking a share at the time of kneading. . In order to add the release agent to the first binder resin in advance, the first binder resin may be synthesized with the release agent added to the monomer when the first binder resin is synthesized. For example, the polycondensation reaction may be performed in a state where a hydrocarbon wax is added to a polyhydric alcohol component and a polycarboxylic acid component constituting the polyester resin as the first binder resin. When the first binder resin is a vinyl-based polyester resin, the vinyl-based resin raw material monomer is dropped into the polyester resin raw-material monomer while stirring and heating the monomer with the hydrocarbon-based wax added. The polycondensation reaction and the radical polymerization reaction may be performed.

  The weight ratio of the first binder resin (including the weight of the internally added wax) to the second binder resin in the colored particles is usually 20/80 to 45/55, and preferably 30/70 to 40/60. . When the weight ratio is less than 20/80, the separation property and the high temperature offset resistance may be deteriorated. Moreover, when it exceeds 45/55, glossiness and heat-resistant storage property may fall.

  In this invention, it is preferable that the softening point of binder resin which consists of 1st binder resin and 2nd binder resin is 100-125 degreeC, Most preferably, it is 105-125 degreeC.

  In the present invention, as the release agent, for example, polyethylene wax, polypropylene wax, carnauba wax, rice wax, sazol wax, montan ester wax, Fischer-Tropsch wax, paraffin wax and the like can be used. When used for a full color toner for oilless fixing, the melting point of the release agent is usually 60 to 100 ° C., preferably 70 to 90 ° C., for example, fatty acid ester, low molecular weight polyethylene, carnauba wax, low melting point. Paraffin or the like can be used. Among these, low melting point paraffin having a low polarity and a high release effect is particularly preferable. In particular, in a color toner for oilless fixing, it is necessary to use a release agent as an essential component. When the melting point of the release agent is lower than 60 ° C., the effect of improving the high temperature offset property may be reduced, and when higher than 100 ° C., the dispersion in the binder resin becomes insufficient, and filming on the photoconductor May occur easily.

  Further, the addition amount of the release agent in the toner is usually 3.5 to 10% by weight, preferably 4 to 8% by weight in the toner by the pulverization method. If the content is less than 3.5% by weight, the release effect may not be exhibited. If the content exceeds 8% by weight, a release mold release agent is generated due to poor dispersion of the release agent during melt kneading. It may become easier to cause filming problems. On the other hand, in the toner by the wet granulation method, it is relatively easy to control the arrangement of the release agent in the toner such as encapsulation, and the dispersion of the release agent or the release of the release agent from the toner by the grinding method is relatively easy. Since there is a margin for release of the mold, the amount of the mold release agent can be increased to 5 to 12% by weight.

  In the present invention, known pigments and dyes can be used as the colorant, and are not particularly limited. For example, carbon black, aniline blue, calcoil blue, chrome yellow, ultramarine blue, DuPont oil red, quinoline yellow, methylene blue chloride, copper phthalocyanine, malachite green oxalate, lamp black, rose bengal, C.I. I. Pigment red 48: 1, C.I. I. Pigment red 122, C.I. I. Pigment red 57: 1, C.I. I. Pigment red 184, C.I. I. Pigment red 269, C.I. I. Pigment red 150, C.I. I. Pigment red 146, C.I. I. Pigment yellow 97, C.I. I. Pigment yellow 12, C.I. I. Pigment yellow 17, C.I. I. Pigment yellow 162, C.I. I. Pigment yellow 180, C.I. I. Pigment yellow 93, C.I. I. Pigment yellow 185, C.I. I. Pigment yellow 74, C.I. I. Pigment yellow 155, C.I. I. Pigment blue 15: 1, C.I. I. Pigment blue 15: 3.

  When a colorant is used for a color toner, it is preferable to use a colorant that has been previously highly dispersed in a resin by subjecting the colorant to a master batch treatment or a flushing treatment. The content of the colorant is preferably 2 to 15 parts by weight with respect to 100 parts by weight of the resin.

  Moreover, it is also possible to mix | blend additives, such as a charge control agent, with a colored particle as needed. Examples of the charge control agent for negatively charged toner include chromium complex type azo dyes S-32, 33, 34, 35, 37, 38, 40 (above, manufactured by Orient Chemical Industries), Eisenspiron Black TRH, BHH ( Above, Hodogaya Chemical Co., Ltd.), Kaya Set Black T-22, 004 (Nippon Kayaku Co., Ltd.), Copper Phthalocyanine Dye S-39 (Orient Chemical Co., Ltd.), Chromium Complex Salt E-81, 82 ( As described above, zinc complex salt E-84 (manufactured by Orient Chemical Industry Co., Ltd.), aluminum complex salt E-86 (manufactured by Orient Chemical Co., Ltd.), boron complex salt LR-147 (manufactured by Nippon Carlit Co., Ltd.) consisting of benzylic acid derivatives. Further, calixarene compounds can be used. Further, as the negative charge control agent used for the full color toner, a colorless, white or light color charge control agent that does not adversely affect the color tone and translucency of the color toner can be used. For example, a salicylic acid derivative such as zinc or chromium is used. Metal complexes, calixarene compounds, organoboron compounds composed of benzylic acid derivatives, fluorine-containing quaternary ammonium salt compounds, and the like are preferably used. Examples of the salicylic acid metal complex include those described in JP-A Nos. 53-127726 and 62-145255, and examples of the calixarene compound include those described in JP-A No. 2-201378. Examples of the organic boron compound described in JP-A-2-221967 can be used, and examples of the organic boron compound described in JP-A-3-1162 can be used. .

  As a method for producing the colored particles, a known production method can be used, and examples thereof include a dry pulverization method, a wet emulsion polymerization, a suspension polymerization, and a dissolution suspension (emulsion granulation) method. Generally, in the case of the pulverization method, amorphous particles can be obtained, and in the case of the wet method, spherical particles can be obtained, and a toner manufacturing method suitable for the image forming process may be used.

  The volume average particle diameter of the colored particles is preferably 4 to 9 μm from the viewpoint of image quality. Especially preferably, it is 4-8 micrometers.

  In the case of producing a toner by a pulverization method, in accordance with conventionally known means, a step of mechanically mixing a binder resin, a release agent (including a case of being internally added to the resin) and a colorant toner component, and melting A toner production method having a kneading step, a pulverizing step, and a classification step can be applied. Further, in the mechanical mixing step or the melt kneading step, powder other than the particles that become the product obtained in the pulverization or classification step may be returned and reused.

  When a toner is produced by an emulsion polymerization association method, at least a release agent is dissolved or dispersed in a vinyl monomer, and the release agent is internally added to the vinyl resin dispersion by a method such as miniemulsion polymerization. The vinyl resin dispersion internally containing the mold agent is assembled and fused together with the pigment dispersion to obtain a toner slurry, which can be isolated by washing, filtering and drying according to known methods. . In this manufacturing method, shape controllability is high, and it is possible to control the shape relatively freely in the range from potato to true sphere.

  The dissolution suspension (elongation) method is a method for producing toner in which oil droplets of an organic solvent in which a toner composition containing a polymer is dissolved is dispersed in an aqueous medium and granulated. A dissolution suspension extension method with improved structure controllability is disclosed in JP-A-2004-139003. This production method is a method for producing a toner by dispersing oil droplets of an organic solvent in which a toner composition containing a prepolymer is dissolved in an aqueous medium and performing an extension reaction and / or a crosslinking reaction. According to this production method, it is possible to use a polyester resin that could not be used in the emulsion polymerization method or suspension polymerization method, and it is possible to produce a full-color toner having particularly excellent fixing characteristics. Further, the molecular weight on the polymer side can be easily controlled by the prepolymer extension reaction by the urethane / urea bond, which is suitable for the production of a full color toner for oilless fixing.

  In the present invention, the method of externally adding inorganic particles to the colored particles is preferably a method of dry mixing with a mixer such as a Henschel mixer. Furthermore, after the treatment, it is preferable to pass through a sieve having an opening of 100 μm or less from the viewpoint of removing foreign substances.

  The toner of the present invention can be obtained by externally adding and mixing inorganic particles A to colored particles. At this time, the inorganic particles B and C may also be externally added and mixed.

  The toner of the present invention can be used as a known electrophotographic toner regardless of whether it is monochrome, color, one component, or two components. In particular, a contact charging method, a blade cleaning method, and an oilless fixing method are used. It is preferable to use for the full color image forming method which has.

  The image forming apparatus of the present invention includes at least a rotatable image carrier, a charging member that is disposed in contact with the image carrier and charges the image carrier to a predetermined potential, and a carrier that rotates to convey toner. A developing device having a member and a supply member for supplying toner to the conveying member; The toner is the toner of the present invention.

  FIG. 1 shows an example of a charging member used in the present invention. The charging member (2) includes a cored bar (3), a conductive layer (5) provided on the cored bar (3), and a surface layer (6) covering the conductive layer (5). It is formed. The voltage applied to the core metal (3) by the power source (7) is applied to the image carrier (1) via the conductive layer (5) and the surface layer (6), and the surface of the image carrier (1). Is to be charged.

  The cored bar (3) of the charging member (2) is disposed along the longitudinal direction of the image carrier (1) (parallel to the axis of the image carrier (1)), and the charging member (2) It is pressed against the image carrier (1) with a predetermined pressing force. As a result, a part of the surface of the image carrier (1) and a part of the surface of the charging member (2) are brought into contact with each other along the longitudinal direction thereof to form a contact nip having a predetermined width. The image carrier (1) is rotationally driven by a driving unit (not shown), and the charging member (2) is configured to be driven to rotate.

  The image carrier (1) is charged by the power source (7) through the vicinity of the contact nip. Through the contact nip, the surface of the charging member (2) and the charged region (corresponding to the length of the charging member (2)) on the surface of the image carrier (1) are in uniform contact, The charged area on the surface of the image carrier (1) is uniform.

  The conductive layer (5) of the charging member (2) is formed using a low-hardness material (in this example, conductive vulcanized rubber) in order to stabilize the contact state with the image carrier (1). It is preferable. Examples of such materials include resins such as polyurethane, polyether, and polyvinyl alcohol, and rubbers such as hydrin, EPDM, and NBR. Examples of the material that imparts conductivity to the conductive layer (5) include carbon black, graphite, titanium oxide, and zinc oxide.

The surface layer (6) is made of a medium resistance (10 ² to 10 ¹⁰ Ω) material (in this example, polyurethane-silicon acrylic polymer containing acetylene black). As the resin material, for example, nylon, polyamide, polyimide, polyurethane, polyester, silicone resin, Teflon (registered trademark), polyacetylene, polypyrrole, polythiophene, polycarbonate, polyvinyl and the like can be used, but the contact angle with water is increased. Therefore, it is preferable to use a fluorine-based resin.

  Examples of the fluorine-based resin include polyvinylidene fluoride, polytetrafluoroethylene, vinylidene fluoride-tetrafluoroethylene copolymer, vinylidene fluoride-tetrafluoroethylene-hexafluoropropylene copolymer, and the like. It is done.

  Furthermore, a conductive material such as carbon black, graphite, titanium oxide, zinc oxide, tin oxide, and iron oxide may be appropriately added to the surface layer (6) for the purpose of adjusting to a medium resistance.

  FIG. 2 shows an example of a developing device used in the present invention. In this image forming apparatus, the image carrier (11) rotates in the direction of the arrow. The developing roller (13) of the developing device (12) contacts the image carrier (11) or holds a gap of 0.1 to 0.3 mm and is driven in the direction of the arrow.

  Around the developing roller (13) is a toner supply roller (14), a material made by attaching a rubber plate (urethane rubber, silicone rubber, etc.) to a plate spring material, or a metal material such as SUS, or a regulating blade (toner layer thickness regulation) Blade) (15) is arranged. A toner feed shaft (16) for supplying toner to the toner supply roller (14) is rotatably disposed in a holding chamber (17) for holding the toner.

As the developing roller (13), for example, a roller in which an elastic rubber layer is coated on a conductive shaft is used, and a surface coat layer made of a material that is easily charged to a polarity opposite to that of the toner is provided on the surface. As the conductive shaft, for example, a metal conductor such as aluminum or stainless steel whose surface is maintained to an appropriate roughness by sandblasting can be used. The elastic rubber layer is set to a hardness of 60 degrees or less according to JIS-A in order to prevent toner deterioration due to pressure concentration at the contact portion with the layer regulating member. The surface roughness Ra is set to 0.3 to 2.0 μm, and a necessary amount of toner is held on the surface. The developing roller (13) is applied with a developing bias for forming an electric field with the image carrier (11), so that the elastic rubber layer has a resistance value of 10 ³ to 10 ¹⁰ Ω. Is done. The developing roller (13) conveys the toner held on the surface to a position facing the image carrier (11) through the regulating blade (15).

  The regulating blade (15) is provided at a position lower than the contact position between the toner supply roller (14) and the developing roller (13). The regulating blade (15) is made of a metal leaf spring material such as SUS or phosphor bronze, and the free end is brought into contact with the surface of the developing roller (13) with a pressing force of 10 to 40 N / m. The toner that has passed under the pressure is thinned and charged by frictional charging. Further, a regulation bias having a value offset in the same direction as the charging polarity of the toner with respect to the developing bias is applied to the regulation blade (15) in order to assist frictional charging.

  Examples of rubber elastic bodies constituting the surface of the developing roller (13) include, for example, styrene-butadiene copolymer rubber, acrylonitrile-butadiene copolymer rubber, acrylic rubber, epichlorohydrin rubber, urethane rubber, silicon rubber, A blend of two or more of these may be mentioned. Among these, a blend rubber of epichlorohydrin rubber and acrylonitrile-butadiene copolymer rubber is preferably used.

  The image forming apparatus of the present invention can form an image using a known exposure device, transfer device, cleaning device, or the like.

  Hereinafter, a method for analyzing the toner and constituent materials used in the present invention will be described.

  The average secondary particle size of the inorganic particles can be measured with a laser diffraction / scattering particle size distribution analyzer LA-920 (manufactured by Horiba, Ltd.). Specifically, the measurement is performed using a sample in which inorganic particles are ultrasonically dispersed in advance in an aqueous medium to which a surfactant is added.

  The average primary particle size of the inorganic particles can be measured by an observation image by SEM or TEM.

  The specific surface area of the inorganic particles can be determined by the BET multipoint method using a specific surface area meter auto soap 1 (manufactured by QUANTACHROME).

  The toner softening point T1 / 2 and the outflow end temperature Tend can be measured by a flow tester CFT-500D (manufactured by Shimadzu Corporation). The extrusion port has a diameter of 0.5 mm and a depth of 1 mm, and the temperature rise is 3 ° C. Per minute. The load applied to the sample was set to 30 kgf.

  The glass transition point and melting point were raised to 200 ° C. using a differential scanning calorimeter DSC6200 (manufactured by Seiko Instruments Inc.), and the sample was cooled to 0 ° C. at a temperature drop rate of 10 ° C./min from that temperature. It is determined by measuring at 10 ° C./min. By this analysis, the glass transition point of the resin and the toner and the melting point of the release agent can be calculated.

The acid value is measured according to JIS K-0070. The specific operation procedure is as follows.
(1) Put the sample W [g] in a 300 ml beaker, and dissolve by adding 150 ml of a toluene / ethanol (4/1: v / v) mixture.
(2) Titrate with a potentiometric titrator using an ethanol solution of 0.1 M KOH. For example, automatic titration can be performed using a potentiometric titrator AT-400 (winworkstation) (manufactured by Kyoto Electronics Co., Ltd.) and an ABP-410 electric burette.
(3) The amount of KOH solution used at this time is set to S [ml], and a blank is measured at the same time, and the amount of KOH solution used at this time is set to B [ml].
(4) The acid value can be calculated by the following formula. Note that f is a factor of an ethanol solution of 0.1 M KOH.

Acid value (mgKOH / g) = {(SB) × f × 5.61} / W
The toner particle size is measured by a Coulter counter method. As an apparatus for measuring the particle size distribution of toner by the Coulter Counter method, there are Coulter Counter TA-II, Coulter Multisizer II, and Coulter Multisizer III (all manufactured by Coulter Co.). The measurement method will be described below.

  First, 0.1 to 5 ml of a surfactant (preferably an alkylbenzene sulfonate) is added as a dispersant to 100 to 150 ml of the electrolytic solution. Here, the electrolytic solution is an about 1% NaCl aqueous solution prepared using primary sodium chloride, and for example, ISOTON-II (manufactured by Coulter) can be used. Here, 2 to 20 mg of the measurement sample is further added as a solid content. The electrolytic solution in which the sample is suspended is subjected to dispersion treatment for 1 to 3 minutes with an ultrasonic disperser, and the volume and number of toners are measured with the measuring device using a 100 μm aperture to obtain the volume distribution and number distribution. calculate. From the obtained distribution, the volume average particle diameter (Dv) and the number average particle diameter (Dn) of the toner can be obtained.

  As a toner shape measurement method, it is possible to use an optical detection band method 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. it can. Toner having an average circularity of 0.96 to 1.00, 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 is preferable because a clear image can be formed. More preferably, the average circularity is 0.98 to 1.00. The average circularity can be measured by a flow type particle image analyzer FPIA-2000. As a specific measurement method, a surfactant (preferably 0.1 to 0.5 ml of alkylbenzene sulfonate is added as a dispersant to 100 to 150 ml of water from which impure solids have been removed in advance in a container, Further, 0.1 to 0.5 g of a measurement sample is added, and the suspension in which the sample is dispersed is subjected to dispersion treatment for 1 to 3 minutes using an ultrasonic disperser, and the concentration of the dispersion is set to 3000 to 10,000 pieces / μl. The average circularity is measured by the apparatus.

  The Mg / Si ratio of the inorganic particles was determined by quantifying the amounts of Mg and Si after preparing a sample using a pressure molding binder with a fluorescent X-ray analyzer ZSX Primus (manufactured by Rigaku Corporation). To calculate the Mg / Si ratio.

The Mg / Si ratio in the vicinity of the surface of the inorganic particles was measured using an X-ray photoelectron spectrometer 1600S type (manufactured by PHI). X-ray source: Mg, Al (400 W)
Analysis area: 0.8-2.0mm
Thus, the surface atomic concentration of Mg and Si is calculated using a relative sensitivity factor (provided by PHI), and the Mg / Si ratio can be obtained from the obtained result.

Next, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples. In the examples, all parts represent parts by weight.
(Production Example 1 of Inorganic Particle A)
The slurry of Mg (OH) ₂ powder and SiO ₂ powder (average primary particle size 0.02 μm) were weighed so that the MgO: SiO ₂ (molar ratio) was 2: 1, and the MgO concentration was 71.5 g / L, A slurry of 150 L with a SiO ₂ concentration of 53.3 g / L is used, and an alumina silica-based bead with a particle diameter of 0.8 mm is used as a medium with a sand grinder mill, a media filling rate of 80%, a feeding speed of 4.0 L / min, and a slurry. Wet pulverization was performed under conditions of 3 passes. The slurry was spray-dried with a spray dryer, and baked at 1100 ° C. for 30 minutes in the air using an electric furnace. Thereafter, the fired product is slurried to 300 g / L, 50 L is sand grinder mill, alumina silica beads having a particle diameter of 0.8 mm are used as media, the media filling rate is 80%, and the feeding speed is 5.6 L. / Min., And wet pulverization was performed under the conditions of 2 passes of slurry pass. The slurry was spray-dried with a spray dryer and pulverized with a sand mill to obtain inorganic particles A-1.

When the inorganic particles A-1 were identified by X-ray diffraction, they were a single phase of forsterite. The average primary particle size is 0.10 μm, the specific surface area is 18.9 m ² / g, the average secondary particle size is 0.39 μm, the Mg / Si ratio is 2.05, and Mg near the surface The / Si ratio was 2.05.
(Production Example 2 of Inorganic Particle A)
In the wet pulverization step, inorganic particles A-2 were obtained in the same manner as in Production Example 1 of inorganic particles A, except that hydrochloric acid was added to the aqueous slurry after pulverization and the acid treatment was performed.

When the inorganic particles A-2 were identified by X-ray diffraction, they were a single phase of forsterite. The average primary particle size is 0.11 μm, the specific surface area is 19.0 m ² / g, the average secondary particle size is 0.40 μm, the Mg / Si ratio is 2.05, and Mg / The Si ratio was 1.64.
(Production Example 3 of Inorganic Particle A)
Except having changed baking temperature into 1200 degreeC, it carried out similarly to manufacture example 2 of the inorganic particle A, and obtained the inorganic particle A-3.

When the inorganic particles A-3 were identified by X-ray diffraction, they were a single phase of forsterite. The average primary particle size is 0.16 μm, the specific surface area is 10.3 m ² / g, the average secondary particle size is 1.5 μm, the Mg / Si ratio is 2.01, and Mg near the surface The / Si ratio was 1.77.
(Production Example 4 of Inorganic Particle A)
Manufacture of inorganic particles A except that MgO: SiO ₂ (molar ratio) was weighed to 1: 1 and the slurry was 150 L with a MgO concentration of 35.8 g / L and a SiO ₂ concentration of 53.3 g / L. In the same manner as in Example 2, inorganic particles A-4 were obtained.

Inorganic particle A-4 was identified by X-ray diffraction and found to be a single phase of enstatite. The average primary particle size is 0.09 μm, the specific surface area is 20.5 m ² / g, the average secondary particle size is 0.40 μm, the Mg / Si ratio is 1.01, and Mg near the surface The / Si ratio was 0.68.
(Production Example 1 of colored particles)
As a vinyl monomer, 600 g of styrene, 110 g of butyl acrylate, 30 g of acrylic acid, and 30 g of dicumyl peroxide as a polymerization initiator were placed in a dropping funnel. Among polyester monomers, as polyols, 1230 g of polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane, polyoxyethylene (2.2) -2,2-bis (4 -Hydroxyphenyl) propane 290 g, isododecenyl succinic anhydride 250 g, terephthalic acid 310 g, 1,2,4-benzenetricarboxylic anhydride 180 g and esterification catalyst, 7 g of dibutyltin oxide, thermometer, stainless steel stirrer, falling condenser and Put in a 5 liter four-necked flask equipped with a nitrogen inlet tube and stir at a temperature of 160 ° C. in a mantle heater under a nitrogen atmosphere, and mix the mixture of vinyl monomer and polymerization initiator from the dropping funnel over one hour. And dripped. While maintaining the temperature at 160 ° C., the addition polymerization reaction was aged for 2 hours, and then the temperature was raised to 230 ° C. to perform the condensation polymerization reaction. The degree of polymerization was tracked by the softening point measured using a constant load extrusion capillary rheometer, and when the desired softening point was reached, the reaction was terminated to obtain Resin H1. T1 / 2 of the obtained resin H1 was 130 ° C.

  As for the resin L1, 1650 g of polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane was obtained in the same manner as the resin H1 except that a vinyl monomer and a release agent were not added. As an esterification catalyst, 660 g of polyoxyethylene (2.2) -2,2-bis (4-hydroxyphenyl) propane, 190 g of isododecenyl succinic anhydride, 750 g of terephthalic acid, 190 g of 1,2,4-benzenetricarboxylic anhydride and A polyester resin was synthesized by charging 0.3 g of dibutyltin oxide. T1 / 2 of the resin L1 thus obtained was 113 ° C.

Resin H1 30 parts Resin L1 70 parts Paraffin wax (melting point: 73.3 ° C.) 5 parts Colorant (copper phthalocyanine blue pigment) 2.5 parts The above materials were sufficiently mixed in a blender, then kneaded in a pressure kneader and cooled. Thereafter, the mixture was pulverized and classified to obtain cyan colored particles 1 having a volume average particle diameter of 7.0 μm.

The acid value of the colored particles 1 was 22.4 mgKOH / g, T1 / 2 was 120 ° C., Tend was 127 ° C., and the average circularity was 0.922.
(Production Example 2 of colored particles)
50 parts of pigment C.I. I. Pigment Blue 15: 3, 10 parts of sodium dodecyl sulfate and 200 parts of ion-exchanged water were dispersed by a sand grinder mill to obtain a cyan colorant dispersion having a volume average particle diameter (D50) of 170 nm.

  A 5000 mL separable flask equipped with a stirrer, temperature sensor, cooling pipe, and nitrogen introducing device was charged with a dispersion medium consisting of 4.05 g of sodium dodecyl sulfate and 2500 g of ion-exchanged water, and stirred at a stirring speed of 230 rpm under a nitrogen stream. The temperature in the flask was raised to 80 ° C. Next, an initiator solution prepared by dissolving 9.62 g of a polymerization initiator (potassium persulfate) in 200 g of ion-exchanged water is added, and from 612 g of styrene, 156 g of n-butyl acrylate, 32 g of methacrylic acid, and 13 g of n-octyl mercaptan. The resulting monomer solution was added dropwise over 90 minutes, and the system was heated and stirred at 80 ° C. for 2 hours to carry out polymerization (first stage polymerization) to prepare 1 L of latex. The T1 / 2 of the dried latex 1L was 124 ° C.

  A 5000 mL separable flask equipped with a stirrer, temperature sensor, condenser, and nitrogen introducing device was charged with a dispersion medium consisting of 4.05 g of sodium dodecyl sulfate and 2500.00 g of ion-exchanged water at a stirring speed of 230 rpm under a nitrogen stream. While stirring, the temperature in the flask was raised to 80 ° C. Next, an initiator solution in which 9.62 g of a polymerization initiator (potassium persulfate) was dissolved in 200 g of ion-exchanged water was added, and 568.00 g of styrene, 164.00 g of n-butyl acrylate, 68.00 g of methacrylic acid, and A monomer solution consisting of 16.51 g of n-octyl mercaptan was added dropwise over 90 minutes, and this system was heated and stirred at 80 ° C. for 2 hours to conduct polymerization (first stage polymerization) to prepare latex 1H. did. The weight average particle diameter of Latex 1H was 68 nm.

  In a flask equipped with a stirrer, a monomer solution consisting of 123.81 g of styrene, 39.51 g of n-butyl acrylate, 12.29 g of methacrylic acid, 0.72 g of n-octyl mercaptan and 75.0 g of paraffin wax was charged. The monomer solution A was prepared by heating to 80 ° C. and dissolving.

Meanwhile, a dispersion medium composed of 0.60 g of C ₁₀ H ₂₁ (OCH ₂ CH ₂ ) ₂ OSO ₃ Na and 2700.00 g of ion-exchanged water is heated to 98 ° C., and latex 1H, which is a dispersion medium for core particles, is heated to this dispersion medium. After adding 32 g in terms of solid content, the monomer solution A was mixed and dispersed for 8 hours using CLEARMIX (M-Technique Co., Ltd.), a mechanical disperser with a circulation path, and emulsified particles (oil droplets) A dispersion (emulsion) containing was prepared. Next, an initiator solution prepared by dissolving 6.12 g of a polymerization initiator (potassium persulfate) in 250 mL of ion exchange water is added to this dispersion (emulsion), and this system is heated and stirred at 82 ° C. for 12 hours. Thus, polymerization (second-stage polymerization) was performed to obtain latex 1HM (a dispersion of composite resin particles having a structure in which the surface of latex 1H particles was coated).

  An initiator solution in which 8.8 g of a polymerization initiator (KPS) is dissolved in 350 ml of ion exchange water is added to latex (1HM), and under a temperature condition of 82 ° C., 350 g of styrene, 95 g of n-butyl acrylate, methacrylic acid are added. A monomer solution consisting of 5 g of acid and 6.1 g of n-octyl mercaptan was added dropwise over 1 hour. Furthermore, after carrying out polymerization (third-stage polymerization) by heating and stirring for 2 hours, the mixture was cooled to 28 ° C., and latex 1HML (a central portion made of latex 1H and an intermediate layer made of second-stage polymerization resin) A composite resin dispersion having an outer layer made of a third-stage polymer resin and a release agent contained in the second-stage polymer resin layer) was obtained. In addition, the quantity of the mold release agent prepared to latex 1HML is 12.5 weight% with respect to a monomer. Moreover, T1 / 2 of dried latex 1HML was 131 ° C.

  240.0 g (converted to solid content) of latex 1 L, 180.0 g (converted to solid content) of latex 1 HML, 900 g of ion-exchanged water and 150 g of cyan colorant dispersion, temperature sensor, cooling pipe, nitrogen introducing device, stirring device It put into the attached reaction container (four necked flask), and stirred. After adjusting the temperature in a container to 30 degreeC, 5N sodium hydroxide aqueous solution was added to this solution, and pH was adjusted to 8-10.0. Next, an aqueous solution obtained by dissolving 65.0 g of magnesium chloride hexahydrate in 1000 ml of ion-exchanged water was added over 10 minutes at 30 ° C. with stirring. After standing for 3 minutes, the temperature was raised to 92 ° C. to produce aggregated particles. In this state, the particle diameter of the aggregated particles was measured with a Coulter counter TA-II. When the volume average particle diameter reached 6.6 μm, an aqueous solution in which 80.4 g of sodium chloride was dissolved in 1000 ml of ion-exchanged water was added. Then, the particle growth was stopped, and as the aging treatment, the particles were fused and the phase separation of the crystalline substance was continued by heating and stirring at a liquid temperature of 94 ° C. (aging process). In this state, the shape of the fused particles was measured with FPIA-2000, and when the average circularity reached 0.952, the mixture was cooled to 30 ° C. and stirring was stopped. The produced fused particles were filtered, washed repeatedly with ion exchange water at 45 ° C., and then dried with hot air at 40 ° C. to obtain colored particles 2. When the volume average particle diameter and the average circularity of the colored particles 2 were measured again, they were 6.5 μm and 0.954, respectively.

The acid value of the colored particles was 25.1 mgKOH / g, T1 / 2 was 127 ° C., and Tend was 135 ° C.
(Production Example 3 of colored particles)
In a reaction vessel in which a stir bar and a thermometer were set, 683 parts of water, 11 parts of sodium salt Eleminol RS-30 (manufactured by Sanyo Chemical Industries), ethylene oxide methacrylate adduct sulfate, 83 parts of styrene, 83 parts of methacrylic acid, When 110 parts of butyl acrylate and 1 part of ammonium persulfate were charged and stirred at 3800 rpm for 30 minutes, a white emulsion was obtained. The system was heated to raise the system temperature to 75 ° C. and reacted for 4 hours. Further, 30 parts of a 1% by weight aqueous ammonium persulfate solution was added, and the mixture was aged at 75 ° C. for 6 hours to form a vinyl resin (a copolymer of styrene-methacrylic acid-butyl acrylate-methacrylic acid ethylene oxide adduct sulfate sodium salt). An aqueous dispersion [fine particle dispersion 1] was obtained. The volume average particle diameter of [fine particle dispersion 1] measured by LA-920 was 110 nm. Further, when a part of [Fine Particle Dispersion 1] was dried to isolate the resin, the Tg of the resin was 58 ° C. and the weight average molecular weight was 130,000.

  990 parts of water, 83 parts of [fine particle dispersion 1], 37 parts of a 48.3% by weight aqueous solution of sodium dodecyldiphenyl ether disulfonate, Eleminol MON-7 (manufactured by Sanyo Kasei Kogyo Co., Ltd.) and 90 parts of ethyl acetate were mixed and stirred. A liquid was obtained. This is designated as [Aqueous Phase 1].

  229 parts of bisphenol A ethylene oxide 2-mole adduct, 529 parts of bisphenol A propylene oxide 3-mole adduct, 208 parts of terephthalic acid, 46 parts of adipic acid and dibutyltin 2 parts of oxide was added and reacted at normal pressure and 230 ° C. for 7 hours. Further, after 5 hours of reaction at a reduced pressure of 10 to 15 mmHg, 44 parts of trimellitic anhydride was placed in a reaction vessel at 180 ° C. and normal pressure. The mixture was reacted for 3 hours to obtain [Low molecular weight polyester 1]. [Low molecular polyester 1] had a number average molecular weight of 2,300, a weight average molecular weight of 6,700, a Tg of 43 ° C., and an acid value of 25 mgKOH / g.

  In a reaction vessel equipped with a cooling pipe, a stirrer and a nitrogen introduction pipe, 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, trimellitic anhydride 22 Part and 2 parts of dibutyltin oxide were added, reacted at normal pressure and 230 ° C. for 7 hours, and further reacted at reduced pressure of 10 to 15 mmHg for 5 hours to obtain [Intermediate Polyester 1]. [Intermediate Polyester 1] had a number average molecular weight of 2200, a weight average molecular weight of 9700, Tg of 54 ° C., an acid value of 0.5 mgKOH / g, and a hydroxyl value of 52 mgKOH / g.

  Next, 410 parts of [Intermediate polyester 1], 89 parts of isophorone diisocyanate, and 500 parts of ethyl acetate are placed in a reaction vessel equipped with a cooling tube, a stirrer, and a nitrogen introduction tube, and reacted at 100 ° C. for 5 hours. Prepolymer 1] was obtained. [Prepolymer 1] had a free isocyanate weight% of 1.53%.

  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 4 and a half hours to obtain [ketimine compound 1]. The amine value of [ketimine compound 1] was 417 mgKOH / g.

  Add 1200 parts of water, 540 parts of carbon black Printex 35 (manufactured by Dexa) (DBP oil absorption = 42 ml / 100 mg, pH = 9.5), 1200 parts of polyester resin, and mix with a Henschel mixer (manufactured by Mitsui Mining). Was kneaded at 130 ° C. for 1 hour using two rolls, rolled and cooled, and pulverized with a pulverizer to obtain [Masterbatch 1].

  378 parts of [Low molecular weight polyester 1], 100 parts of carnauba wax, and 947 parts of ethyl acetate were charged in a container equipped with a stirring bar and a thermometer, heated to 80 ° C. with stirring, and maintained at 80 ° C. for 5 hours. Cooled to 30 ° C. in 1 hour. Next, 500 parts of [Masterbatch 1] and 500 parts of ethyl acetate were charged into a container and mixed for 1 hour to obtain [Raw material solution 1].

  [Raw material solution 1] Transfer 1324 parts to a container, and use a bead mill Ultra Visco Mill (manufactured by Imex) to feed zirconia beads having a liquid feeding speed of 1 kg / hour, a disk peripheral speed of 6 m / second, and a particle diameter of 0.5 mm. Filled with 80% by volume, carbon black and wax were dispersed under the condition of 3 passes. Next, 1324 parts of a 65% by weight ethyl acetate solution of [low molecular weight polyester 1] was added, and the mixture was passed through a bead mill under the above conditions to obtain [Pigment / Wax Dispersion 1]. The solid content concentration of [Pigment / Wax Dispersion 1] (measurement conditions: 130 ° C., 30 minutes) was 50% by weight.

  [Pigment / Wax Dispersion 1] 749 parts, [Prepolymer 1] 115 parts, [Ketimine Compound 1] 2.9 parts are put in a container, and 2 at 5000 rpm using a TK homomixer (manufactured by Koki Co., Ltd.). After mixing for 1 minute, 1200 parts of [Aqueous Phase 1] was added to the container and mixed for 25 minutes at 13000 rpm using a TK homomixer to obtain [Emulsified Slurry 1].

  [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 7 hours to obtain [Dispersion slurry 1].

[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 (12000 rpm for 10 minutes), and then filtered.
(2) 100 parts of a 10 wt% aqueous sodium hydroxide solution was added to the filter cake of (1), mixed with a TK homomixer (30 minutes at 12000 rpm), and then filtered under reduced pressure.
(3) 100 parts of 10 wt% hydrochloric acid was added to the filter cake of (2), mixed with TK homomixer (12000 rpm for 10 minutes), 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 12000 rpm), and then filtered twice to obtain [Filter cake 1].

[Filtration cake 1] was dried at 45 ° C. for 48 hours using a circulating dryer, and sieved with a mesh of 75 μm to obtain colored particles 3. The T1 / 2 of the colored particles 3 was 108 ° C.
(Examples and Comparative Examples)
As shown in Table 1, inorganic particles were added to 100 parts of the colored particles, mixed with a Henschel mixer, and then screened with a vibration sieve to obtain a toner.

なお、表１における無機粒子Ａ−５、Ｂ−１〜Ｂ−３、Ｃ−１〜Ｃ−３は、表２に示す。

In addition, Table 2 shows inorganic particles A-5, B-1 to B-3, and C-1 to C-3 in Table 1.

（評価方法及び評価結果）
実施例及び比較例で得られたトナーを各評価項目について、以下の方法に従って評価した。
（１）現像ノイズ
各トナーを接触帯電ローラ方式、非磁性１成分現像方式を採用するタンデムフルカラープリンタＩＰＳｉＯ ＣＸ−３０００（リコー社製）にセットし、印字率が１５％の画像チャートを用いて８０００枚連続印字したときの帯電不良による画像地汚れ、現像ローラーのフィルミング、スジ等の発生状況を評価した。

(Evaluation method and evaluation results)
The toners obtained in Examples and Comparative Examples were evaluated according to the following methods for each evaluation item.
(1) Development noise Each toner is set in a tandem full-color printer IPSiO CX-3000 (manufactured by Ricoh) using a contact charging roller system and a non-magnetic one-component development system, and 8000 using an image chart having a printing rate of 15%. Evaluation was made on the occurrence of image background smearing, filming on developing rollers, streaks, and the like due to poor charging during continuous printing.

  A: No soiling, filming, streaks, or thin layer formation failure occurred.

  ◯: Some of background contamination, filming, streaks, or thin layer formation was slightly occurring, but the level was not problematic in practical use.

  (Triangle | delta): Any of background stain | pollution | contamination, filming, a stripe | line | column, and thin layer formation defect generate | occur | produced, and it was the level which becomes a problem practically.

×: Many of ground stain, filming, streaks, and thin layer formation failure occurred.
(2) Cleanability In the same manner as in (1), the state of occurrence of uncleaned cleaning on the photoconductor after printing 8,000 sheets was evaluated.

  ○: No wiping residue due to poor cleaning occurred.

X: A wiping residue due to poor cleaning occurred.
(3) Photoconductor Noise In the same manner as in (1), the filming and streak generation conditions on the photoconductor after printing 8000 sheets were evaluated.

  ○: Filming and streaks were not generated on the surface of the photoreceptor.

X: Filming and streaks were generated on the surface of the photoreceptor.
(4) Charging roller noise In the same manner as in (1), the occurrence of filming of the contact charging roller after printing 8000 sheets was evaluated.

  A: Filming and photoreceptor charging failure did not occur on the charging roller surface.

X: Filming and photoconductor charging failure occurred on the surface of the charging roller.
(5) Omission in transfer In the same manner as in (1), a thin line image after printing 8000 sheets was output to evaluate the occurrence of transfer omission.

  ○: The level of omission in transfer was at a level causing no problem in practical use.

  X: Omission in transfer occurred and was a level causing a problem in practical use.

  The above evaluation results are shown in Table 3.

以上説明したように、本発明のトナーは、帯電性が良好であり、帯電部材の表面や感光体の表面への固着やキズの発生を抑制することができる。また、接触帯電工程とのマッチングが極めて良好であり、帯電部材の能力を充分発揮させ、常に良好な画像形成を行うことができた。

As described above, the toner of the present invention has good chargeability, and can suppress adhesion to the surface of the charging member and the surface of the photoreceptor and the generation of scratches. In addition, the matching with the contact charging process was very good, the charging member was fully demonstrated, and good image formation was always possible.

It is a figure which shows an example of the charging member used by this invention. It is a figure which shows an example of the image development apparatus used by this invention.

Claims (15)

In a toner having colored particles containing a binder resin, a colorant and a release agent, and first inorganic particles,
The first inorganic particles have an average secondary particle diameter of Ru der least 2μm or less 0.02 [mu] m, a MgSiO ₂ particles or _Mg 2 SiO ₄ grains,
The first atomic concentration ratio of Mg to Si in the inorganic particles, toner being greater than the atomic concentration ratio of Mg to Si in the vicinity of the surface of the first inorganic particles.   The toner according to claim 1, wherein the first inorganic particles have an average primary particle size of 0.02 μm or more and 0.15 μm or less.   The toner according to claim 2, wherein the first inorganic particles are sintered aggregates having an average secondary particle size of 0.05 μm or more and 2 μm or less.   The toner according to claim 1, wherein the first inorganic particles are externally added to the colored particles.   The toner according to any one of claims 1 to 4, wherein the first inorganic particles are forsterite, enstatite, or steatite. The first inorganic particles are obtained by performing acid treatment after sintering Mg (OH) ₂ particles or MgO particles and SiO ₂ particles having an average primary particle size of 0.10 μm or less. The toner according to claim 1.   A second inorganic particle having an average primary particle size of 5 nm to 20 nm and made of hydrophobic silica; and a third inorganic particle having an average primary particle size of 20 nm to 100 nm and made of hydrophobic titania or hydrophobic silica. The toner according to claim 1, further comprising inorganic particles. The ratio of the total weight of the second inorganic particles and the third inorganic particles to the weight of the colored particles is 2% or more and 5% or less,
The toner according to claim 7, wherein a ratio of the weight of the first inorganic particles to the weight of the colored particles is 0.3% or more and 5% or less.   The toner according to claim 7 or 8, wherein a weight ratio of the second inorganic particles to the third inorganic particles is 1/9 or more and 7/3 or less. Before SL colored particles have a volume average particle size is at 4μm or 9μm or less,
The toner according to claim 1, wherein the toner is used in a nonmagnetic one-component development system. Before SL colored particles have a volume average particle size is at 4μm or 9μm or less,
The toner according to claim 1, wherein the toner is used in a two-component development system.   12. The toner according to claim 1, wherein the colored particles contain the releasing agent in an amount of 3.5 wt% or more and 10 wt% and are manufactured by a pulverization method.   12. The toner according to claim 1, wherein the colored particles contain the release agent in an amount of 5 wt% to 12 wt% and are manufactured by a wet granulation method. . Gyrus and rotatably image bearing member,
Disposed in contact with said image bearing member, a charging member Ru charges the image bearing member to a predetermined potential,
It rotates in an image forming apparatus having a developing device having a supply member for supplying the conveying member and the toner on the conveying member conveys the toner,
The image forming apparatus according to claim 1, wherein the toner is the toner according to claim 1. An image bearing member, an electrostatic latent image formed on the image bearing member is developed with a toner developing device for forming a toner image is supported on one body, in a free process cartridge detachable to the main body of the image forming apparatus ,
The process cartridge according to claim 1, wherein the toner is the toner according to claim 1.

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