JP2006243718A - Image forming method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress winding of a recording material around a fixing member and disarray of a developer in a fixing step in an image forming apparatus capable of forming an entirely frameless image. <P>SOLUTION: In an image forming method including: an electrostatic latent image forming step of forming an electrostatic latent image on a charged image carrier; a developing step of developing the electrostatic latent image by shifting a toner to the latent image; a transfer step of electrostatically transferring the resulting toner image visualized by the toner on the image carrier onto a recording material; and a fixing step of heat-fixing the toner image on the recording material, an image whose length in at least one of main and secondary scanning directions is larger than the length of the recording material is formed on the image carrier, part of the image is transferred onto the recording material and fixed, and the toner is a color toner obtained by a wet process including: an agglomerating step of preparing an agglomerated particle dispersion by forming agglomerated particles in a dispersion prepared by dispersing fine resin particles containing a binder resin and a release agent and colorant particles; and a fusing step of fusing the agglomerated particles by heating the agglomerated particle dispersion. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an image forming method using a color toner for developing an electrostatic latent image.

  Opportunities for consumers to output image data collected by digital cameras, digital video cameras, and the like in electrophotographic image forming apparatuses such as digital copying machines and digital laser printers are increasing. Therefore, it has become necessary to stretch the image over the entire surface of the paper in the same manner as in the development of a conventional optical film camera. In response to such a request, in recent years, proposals have been made to add an image forming function without a border to an image forming apparatus (Patent Documents 1 and 2).

  In order to form an image having no border, it is necessary to limit the thickness, gloss and strength of the recording material. This is because the toner used in the electrophotographic image forming apparatus needs to be appropriately fixed on the image in order to achieve an image quality equivalent to that of a film photograph. There has also been a proposal regarding the color tone at the time of fixing (Patent Document 3).

  Furthermore, in the future, as the speed of the printer is increased, further lubricity at the time of fixing will be required. When the printing speed is increased, in the fixing process, peeling discharge is likely to occur when the recording material is separated from the fixing member, and the toner layer that forms a visible image on the recording material may be disturbed. Rise. As such adverse effects on the image due to the disturbance of the toner layer, “fixing scattering” and “peeling offset” are known. For this reason, it is known that neutralizing the charge of the recording material at the time of recording material separation is an effective means (Patent Document 4).

JP 2003-98915 A JP 2004-45457 A JP 2004-1108020 A JP 2004-54182 A

  In the fixing process of the image forming apparatus capable of forming an image with no border on the entire surface, the winding of the recording material around the fixing member and the disturbance of the developer are suppressed.

  The present invention is an image forming method characterized by the following configuration.

(1) A charging step in which a voltage is applied to the charging member to charge the image carrier, an electrostatic latent image forming step in which an electrostatic latent image is formed on the charged image carrier, and the electrostatic latent image A development process in which the toner is transferred and developed, a transfer process in which the toner image visualized on the image carrier by the toner is electrostatically transferred to the recording material with or without the intermediate transfer member, and recording In an image forming method having a fixing step of heating and fixing a toner image on a material and repeatedly forming an image on an image carrier,
In the image forming method, an image having at least one of the main scanning direction and the sub-scanning direction longer than the length of the recording material is formed on the image carrier, and a part of the image is transferred to the recording material and fixed. ,
The toner includes an aggregating step of forming an aggregated particle dispersion in a dispersion in which at least a binder resin, resin fine particles including a release agent, and a colorant particle are dispersed to prepare an aggregated particle dispersion; and the aggregated particle dispersion An image forming method, which is a color toner obtained by a wet manufacturing method including a fusing step of fusing the aggregated particles by heating.

  (2) The image forming method as described in (1), wherein the color toner contains a polar resin having a sulfur atom.

  (3) The image forming apparatus according to (1) or (2), wherein the color toner is obtained by adding a compound represented by the following structural formula as a charge control agent during the aggregation process. Method.

（式中、環ＡおよびＲは、それぞれ置換基を有していてもよい芳香族環残基を表し、−ＯＨと−ＣＯＮＨ−Ｒは芳香族環残基Ａ上で相隣る置換位置に結合している。）

(In the formula, each of rings A and R represents an aromatic ring residue which may have a substituent, and —OH and —CONH—R are adjacent to each other on the aromatic ring residue A. Combined.)

（式中、Ａ¹、Ａ²、Ｒ¹およびＲ²は、それぞれ置換基を有していてもよい芳香族環残基を表し、Ｂは２価の有機基を表す。また、式中の−ＯＨと−ＣＯＮＨ−Ｒ¹および−ＯＨと−ＣＯＮＨ−Ｒ²は芳香族環残基Ａ１、Ａ²上で相隣る置換位置に結合している。）

(In the formula, A ¹ , A ² , R ¹ and R ² each represent an aromatic ring residue which may have a substituent, and B represents a divalent organic group. -OH and -CONH-R ¹ and -OH and -CONH-R ² is attached to the Aitonaru substitution positions on the aromatic ring residue A1, a ^2.)

  (4) The image forming method as described in any one of (1) to (3), wherein the binder resin in the color toner has a peak molecular weight in the range of 5000 to 30000.

  When the electrostatic latent image developer according to the present invention is used, a good image with no border can be obtained.

[Means for forming an image with no borders]
In the electrophotographic image forming apparatus of the present invention, the surface of the photoreceptor is uniformly charged by the charging process, and then the charged surface of the photoreceptor is exposed according to the image data by the exposure process to write the electrostatic latent image. Then, the electrostatic latent image is developed by attaching toner in a developing process to generate an original image which is a visible image, and the original image is transferred onto a recording material by a transfer process. Thereafter, the recording material is fed into a fixing process, the original image on the paper is thermally fixed by applying pressure with a high-temperature and high-pressure roller, and the recording material is discharged out of the apparatus.

  At this time, there are an area in the main scanning direction and an area in the sub-scanning direction in the area where the electrostatic latent image can be formed by the exposure process. The region in the main scanning direction on the photoconductor is a region from a laser beam irradiation start position to a laser beam irradiation end position in a direction parallel to the rotation axis of the photoconductor. Further, the sub-scanning direction area on the surface of the photosensitive member is an area from the irradiation position of the first main scanning line to the irradiation position of the last main scanning line in one page of image data.

  The exposure process will be specifically described. First, a rotating polygon mirror is irradiated with a laser beam from a semiconductor laser as a light source. Then, the laser beam periodically deflected and reflected is focused by the scanning lens, and the photosensitive member rotating in the sub-scanning direction is repeatedly scanned in the main scanning direction orthogonal to the sub-scanning direction. Then, the electrostatic latent image is exposed.

  In the entire borderless printing mode provided in the electrophotographic image forming apparatus of the present invention, this electrostatic latent image formable area is different.

  That is, in the full-borderless printing mode, the main scanning direction area and the sub-scanning direction area of the electrostatic latent image formable area are larger than in the bordered printing mode. This is because when printing an image with no border, the image is printed on a borderless image to correct and erase the margin caused by a small size error between the image size of the image data and the actual size of the recording material. This is because it is necessary to reflect the magnification.

  When the full borderless printing mode is selected, the exposure unit sets the image resolution by setting the main scanning pixel clock and the polygon mirror rotation period. The main scanning pixel clock is set by a write clock generation circuit. The polygon mirror rotation period is set by a rotation motor control circuit of the polygon mirror. Further, the exposure unit finely adjusts the settings of the main scanning pixel clock and the polygon rotation period, thereby performing main scanning magnification adjustment and sub-scanning magnification adjustment in the bordered printing mode. Based on this, main scanning magnification adjustment and sub-scanning magnification adjustment for an image having no border on the whole surface in the borderless printing mode are performed.

  As described above, the electrostatic latent image formed on the photoconductor in the exposure process becomes a visible image by the toner in the development process, and is transferred to the recording material in the transfer process.

[Configuration of transfer process]
When the image forming apparatus as shown in FIG. 2 is used, the primary transfer roller 12 in the transfer process is a roller in which a core metal is covered with a rubber such as urethane, EPDM, NBR, or a sponge-like elastic layer obtained by foaming them. The transfer nip T having a predetermined width is formed by contacting the photosensitive member with a predetermined pressing force. A roller having a roller hardness of 40 ° or less (Asker-C hardness, 500 g load) is used to prevent missing characters in the transfer and scraping of the photoreceptor. Carbon and metal fine powder are uniformly dispersed in this elastic layer, and a medium resistance roller with a volume resistivity of 10 ⁶ to 10 ⁹ Ω · cm is used, so that even with a relatively high resistance recording material, good electrostatic Can perform transcription. If the volume resistivity is less than 10 ⁶ Ω · cm, an excessive current flows to the photosensitive drum 1 and damages the photosensitive drum. Conversely, if the volume resistivity is greater than 10 ⁹ Ω · cm, the current necessary for transfer is increased. Insufficient transfer results.

  Therefore, there is an optimum value for the resistance value of the primary transfer roller 12. At this time, an appropriate voltage of 1 kV to 6 kV is applied to the primary transfer roller 17 according to the resistance value from the cored bar.

  In addition, the primary transfer roller 12 uses a gear (not shown) to prevent peripheral holes (outer diameter of the primary transfer roller 12) from occurring in order to prevent “collapse” that easily occurs when the recording material is OHT or thick paper. (Value calculated from the above) is rotated as fast as 105% to 120% with respect to the photosensitive member. As a result, the conveyance speed of the actual recording material or intermediate transfer member is increased by about 1% with respect to the photosensitive member.

The intermediate transfer belt 20 is made of a resin such as polyimide or polyamide containing an appropriate amount of a conductive material such as carbon black, and has a volume resistivity of 10 ⁶ to 10 ¹⁴ Ω · cm. Yes.

  The secondary transfer devices 17 and 18 include a secondary transfer roller 18 disposed in pressure contact with the toner image carrying surface side of the intermediate transfer belt 20, and a counter electrode of the secondary transfer roller 18 disposed on the back surface side of the intermediate transfer belt 20. The secondary transfer bias is stably applied to the backup roller 17.

In the present embodiment, the secondary transfer roller 18 is made of a urethane rubber tube having carbon dispersed on the surface, and the inside is made of foamed urethane rubber having carbon dispersed. Further, the roller surface is coated with fluorine to form a volume resistance of 10 ³ to 10 ¹⁰ Ω · cm.

  Through such a transfer process, the recording material onto which the visible image formed by the toner is transferred is sent to the fixing process.

[Configuration of fixing process]
The fixing device used in the present invention has the following configuration.

  The fixing device is a fixing device as shown in FIG. 1, and includes a heating roll 14 and a pressure roll 15. The heating roll 14 has a roll structure in which a heating electromagnetic induction coil 24 is disposed inside a hollow of a cylindrical roll core 23 made of a metal material. As the metal material of the roll core material 23, a material having high thermal conductivity such as iron, aluminum, stainless steel or the like is used. The heating roll 14 is provided with an elastic layer made of silicone rubber or the like on the outer peripheral surface of the roll core 23 as necessary, or a surface release layer 22 made of fluorine-based resin (PFA or the like) on the outermost surface. Can be provided. When providing an elastic layer, it is preferable to form the elastic layer having a thickness of 1 to 3 mm.

  The electromagnetic induction coil 24 is feedback-controlled so that the heating operation can be heated at a predetermined temperature based on the detection information of the surface temperature of the heating roll 26. The heating roll 26 is rotatably supported in the direction of arrow C at a predetermined speed by a rotational driving force transmitted from a rotational driving source (not shown) while the roll core member 23 is rotatably supported. Yes.

  The pressure roll 15 has substantially the same roll structure as the heating roll 14 except that an elastic layer 21 made of silicone rubber or the like is provided on the outer peripheral surface of the roll core member 23. The pressure roll 25 is configured such that the roll core member 23 is rotatably supported and is pressed against the heating roll 26 with a predetermined pressure by a pressure mechanism (not shown). A pressure contact portion (fixing nip portion) is formed between the pressure roll 15 and the heating roll 14. The pressure applied by the pressure mechanism is set so that the pressure at the fixing nip is 0.5 to 3 MPa.

  Conventionally, as a means for solving the toner offset problem in the fixing device, a method of applying a release agent such as silicone oil to the surface of the heat fixing means with a web, a pad or the like, or collecting the offset toner on a cleaning member has been taken. It was.

  However, recently, a configuration in which a bias is applied to one or both of the heating roller 14 and the pressure roller 15 to prevent toner offset on the heat fixing unit has become widespread. By the way, when a bias is applied to the fixing device as described above, the recording material and the heat fixing unit are likely to be electrostatically adsorbed, and the charge held by the recording material is liable to cause peeling charging at the time of separation from the heat fixing unit. There was a drawback. When printing without borders on the entire surface, the timing of discharging the trailing edge of the recording material is delayed, so that the surface of the fixing roller as the heat fixing unit is peeled and charged. As a result, the image on the recording material after one rotation of the fixing roller is disturbed, or a so-called “peeling offset” is generated, which causes an offset after one rotation of the fixing roller.

  In other words, in the image forming process, the recording material after the toner image transfer has a charge opposite in polarity to the toner, and the toner is electrostatically held on the recording material. In order to prevent the offset to the fixing unit, it is effective to generate a potential difference in the direction in which the toner is pressed against the recording material in the fixing step. As a result, the cleaning member becomes unnecessary, the fixing device can be reduced in size and cost, and the user can save time and effort to replace the cleaning member periodically.

  There are mainly the following two methods for applying a bias to the fixing device.

  A) One is that the heating roller 14 side induces a potential of the same polarity as the toner on the surface, while the pressure roller 15 side pressed against the heat fixing means has a diode on a roller metal core made of conductive rubber. In this system, the electric charge having the same polarity as that of the toner is removed by the electrode effect.

  B) The other is that the conductive substrate on the heating roller 14 side is grounded or a weak bias having the same polarity as that of the toner is applied, and the elastic roller side that is in pressure contact with the heat fixing means has a low resistance release layer on the surface. And applying a reverse polarity bias.

  The former A has a merit that an insulating fluororesin can be used as the surface release layer 22 and has high releasability and is difficult to get dirty. On the other hand, the charge held by the recording material varies depending on the type and printing rate of the recording material, There is a drawback that the potential is difficult to stabilize. In addition, if there is a leak site on the surface of the heat fixing unit, in the case of a recording material that has absorbed moisture, current flows between the recording material and transfer-fixing, so the toner holding charge of the recording material disappears and back scattering occurs. There is.

  On the other hand, since the latter B can supply the charge for holding the toner from the back side of the recording material, there is an advantage that the potential of the surface of the recording material and the fixing member is stabilized and offset is hardly generated.

  In order to prevent peeling electrification due to the recording material, measures are taken such that the primer for bonding the roll core material 23 is made conductive rather than the surface release layer 22 to increase the capacitance of the heat fixing means. Further, it is known that it is an effective means to remove the charge of the recording material during separation. As a method therefor, it has been proposed to apply a bias while the recording material is in the fixing nip and to turn off the applied bias in accordance with the timing at which the trailing edge of the recording material reaches the fixing nip. There is also a method in which a bias is applied to a charging member disposed near the nip of the fixing device to supply toner holding charges from the back of the recording material in accordance with the timing when the recording material comes.

[Toner and image forming method]
However, in the process of earnestly studying the present invention, it has been found that it is difficult to eliminate the above-described adverse effects of the image only by improving the fixing process and the transfer process.

  Therefore, by adding a binder resin having a specific molecular weight distribution and a charge control agent proposed in the present invention in the course of toner production, in addition to maintaining the charging ability of the toner, the circularity standard deviation is small, A toner having a small difference in charge distribution between toner particles to be developed and transferred can be produced. As a result, the toner loading amount on the developer carrying member is stabilized, so that the developability of the entire solid image in continuous paper passing at high temperature and high humidity is improved. In addition, it has been found that voids caused by development of poorly charged toner are also improved.

  In addition, by combining the charge control agent of the present invention and the colorant, the binder resin has a weak crosslinkability as compared with the conventional color toner charge control agent. For this reason, in the present invention, the toner discharge capacity is suppressed while maintaining the toner charge capacity, and the toner is rapidly fused during fixing by controlling the glass transition temperature and viscoelasticity. Made possible. As a result, it was possible to remove adverse effects such as peeling offset during fixing and toner scattering on the image.

[Production method of color toner particles]
The method for producing the toner is not particularly limited. (1) Aggregated particles are formed by forming aggregated particles in a dispersion obtained by dispersing at least a binder resin, resin fine particles containing a release agent, and colorant particles. (2) adding and mixing a fine particle dispersion in which fine particles are dispersed in the aggregated particle dispersion to adhere the fine particles to the aggregated particles to form adhered particles; and (3 And a step of heating and fusing the adhered particles to form toner particles.

In this case, the resin fine particles and the dispersant for the colorant particles used are aqueous media containing a surfactant. Examples of the aqueous medium include water such as distilled water and ion exchange water, and alcohols.
The granulation of the fine particles in the present invention is preferably performed under high speed shearing. In particular, in order to form fine particles, it is preferable to select a disperser equipped with a high-speed shearing mechanism. Among them, high-speed blade rotating type or forced interval passing type emulsifiers such as various homomixers, homogenizers, colloid mills, etc. More preferably, is used.

  The color toner production method of the present invention is an emulsification / aggregation method in which aggregates are produced from various emulsified particles to form toner particles. The manufacturing method preferably includes at least a fine particle mixture preparation step and includes an aggregated particle formation step, a fusion step, and a cooling step. Furthermore, in this invention, another process can be included as needed.

  In the fine particle mixture preparation step, the binder resin fine particles, the colorant fine particles, and the like are uniformly dispersed and mixed in the mixed solution of the binder resin particle dispersion, the colorant particle dispersion, etc. in the aqueous medium. . In the aggregated particle forming step, fine particles of the binder resin, fine particles of the colorant and the like that are uniformly dispersed in the mixed solution are aggregated to form aggregated particles. In the fusing step, the resin in the aggregated particles melts and fuses to form color toner particles.

  In the attached particle forming step, the fine particles contained in the fine particle dispersion added and mixed in the aggregated particle dispersion in which the aggregated particles are dispersed adhere to the surface of the aggregated particles as the mother particles. Particles are formed. When the adhered particle forming step is included before the fusing step, in the fusing step, the resin in the adhered particles is melted and fused to form electrostatic charge image developing toner particles.

  The distribution of the fine particles of the colorant in the aggregated particles finally becomes the distribution of the colorant particles in the toner particles. Therefore, the smaller the dispersion of the colorant particles, the more uniform the color development of the resulting toner particles. Improves. In the method for producing a color toner of the present invention, since the colorant particles are uniformly dispersed in the aggregated particles in the aggregated particle forming step, the color toner particles obtained have very good color developability. . This color development is important because it directly affects the color reproducibility and the like, but the electrostatic image developing toner obtained by the method for producing color toner particles of the present invention is advantageous in terms of color reproducibility and the like. Further, the color toner particles are advantageous in that they can be easily washed and have excellent charging properties, and their characteristics, particularly charging properties, do not easily vary depending on environmental conditions.

  The combination of the fine particles of the colorant and the fine particles of the binder resin is not particularly limited and can be selected. The particle dispersion may contain fine particles such as fine particles of an internal additive, fine particles of a charge control agent, inorganic fine particles, organic fine particles, fine particles of a lubricant, fine particles of an abrasive, and the like. The fine particles that may be mixed are not particularly limited and may be appropriately selected depending on the purpose. In the present invention, these fine particles such as release agent fine particles may be dispersed in the resin particle dispersion or the colorant particle dispersion.

  As the surfactant, ionic or nonionic surfactants can be used. Specifically, alkylbenzene sulfonate, alkylphenyl sulfonate, alkyl naphthalene sulfonate, higher fatty acid salt, sulfate of higher fatty acid ester, sulfonic acid of higher fatty acid ester, etc. can be used as an anionic surfactant. . As the cationic activator, primary to tertiary amine salts, quaternary ammonium salts and the like can be used. Nonionic activators include polyoxyethylene nonyl phenyl ether, polyoxyethylene octyl phenyl ether, polyoxyethylene dodecyl phenyl ether, polyoxyethylene alkyl ether, polyoxyethylene fatty acid ester, sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester , Fatty acid alkylolamide and the like can be used. These dispersion stabilizing aids may be used alone or in combination of two or more. These dispersion stabilizing aids are preferably used in the range of 0.001 to 5 parts by mass with respect to 100 parts by mass of the main medium of the aqueous phase.

  In the present invention, in order to control the internal structure of the toner obtained by the growth due to the aggregation of the fine particles, it is preferable to add the resin fine particles sequentially while the aggregation of the fine particles is in progress. Thus, in the initial stage of particle aggregation, the resin fine particles enter the toner, and the resin fine particles added thereafter can cover the surface of the toner.

  The obtained toner is preferably washed with an acid such as hydrochloric acid, nitric acid, formic acid or acetic acid which makes the inorganic dispersion stabilizer water-soluble. This washing removes the inorganic dispersion stabilizer remaining on the toner surface. In the case of a toner in which the inorganic dispersion stabilizer or the above-described surfactant remains on the toner surface, if the residual deposits are hygroscopic, the dependency of the charging property on the environment is reduced. It is preferable to remove as much as possible to reduce the influence on the chargeability and powder flowability of the toner.

  The acid-treated or alkali-treated toner may be washed again with an alkaline water such as sodium hydroxide as necessary. As a result, when placed under a basic condition, a part of the ionic substance on the surface of the insolubilized toner is solubilized and removed, and the chargeability and powder flowability of the toner are improved. Further, when the toner is washed with acid or alkaline water, there is an advantage that the wax which has been released and adhered to the toner surface can be washed away. In addition to conditions such as pH at the time of washing, the number of times of washing, and temperature at the time of washing, washing is preferably performed using a stirrer, an ultrasonic dispersion device, or the like. Further, if necessary, the toner for electrophotography of the present invention can be obtained by drying by filtration, centrifugation or the like.

[Binder resin in resin particles]
Examples of the monomer that is a constituent component of the binder resin contained in the resin fine particles in the present invention include vinyl monomers capable of radical polymerization. As the vinyl polymerizable monomer, a monofunctional polymerizable monomer or a polyfunctional polymerizable monomer can be used.

  Monofunctional polymerizable monomers include styrene; α-methylstyrene, β-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, 2,4-dimethylstyrene, pn-butyl. Styrene, p-tert-butyl styrene, pn-hexyl styrene, pn-octyl styrene, pn-nonyl styrene, pn-decyl styrene, pn-dodecyl styrene, p-methoxy styrene, p -Styrene derivatives such as phenylstyrene; methyl acrylate, ethyl acrylate, n-propyl acrylate, iso-propyl acrylate, n-butyl acrylate, iso-butyl acrylate, tert-butyl acrylate, n-amyl acrylate, n-hexyl acrylate, 2 -Ethylhexyl acrylate , N-octyl acrylate, n-nonyl acrylate, cyclohexyl acrylate, benzyl acrylate, dimethyl phosphate ethyl acrylate, diethyl phosphate ethyl acrylate, dibutyl phosphate ethyl acrylate, 2-benzoyloxyethyl acrylate Methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, iso-propyl methacrylate, n-butyl methacrylate, iso-butyl methacrylate, tert-butyl methacrylate, n-amyl methacrylate, n-hexyl methacrylate, 2-ethylhexyl methacrylate, n-octyl Methacrylate, n-nonyl methacrylate, diethyl phosphate ethyl methacrylate Methacrylic polymerizable monomers such as dibutyl phosphate ethyl methacrylate; methylene aliphatic monocarboxylic acid esters; vinyl esters such as vinyl acetate, vinyl propionate, vinyl acetate, vinyl benzoate, vinyl formate; vinyl methyl ether Vinyl ether such as vinyl ethyl ether and vinyl isobutyl ether; vinyl ketone such as vinyl methyl ketone, vinyl hexyl ketone and vinyl isopropyl ketone.

  Also, ethylenically unsaturated monoolefins such as ethylene, propylene and butylene; vinyl halides such as vinyl chloride, vinylidene chloride and vinyl fluoride; vinyl esters such as vinyl acetate and vinyl propionate; 2-vinylpyridine, 4-vinyl And monovinyl monomers such as nitrogen-containing vinyl compounds such as pyridine and N-vinylpyrrolidone;

  As polyfunctional polymerizable monomers, diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol diacrylate, 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, tripropylene glycol Diacrylate, polypropylene glycol diacrylate, 2,2′-bis (4- (acryloxydiethoxy) phenyl) propane, trimethylolpropane triacrylate, tetramethylolmethane tetraacrylate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol Dimethacrylate, tetraethylene glycol dimethacrylate, polyethylene glycol Dimethacrylate, 1,3-butylene glycol dimethacrylate, 1,6-hexanediol dimethacrylate, neopentyl glycol dimethacrylate, polypropylene glycol dimethacrylate, 2,2'-bis (4- (methacryloxy-diethoxy) phenyl) propane, Examples include 2,2′-bis (4- (methacryloxy / polyethoxy) phenyl) propane, trimethylolpropane trimethacrylate, tetramethylolmethane tetramethacrylate, divinylbenzene, divinylnaphthalene, and divinyl ether.

  In the present invention, the above monofunctional polymerizable monomers are used alone or in combination of two or more, or the above monofunctional polymerizable monomers and polyfunctional polymerizable monomers are used in combination. To do. The polyfunctional polymerizable monomer can also be used as a crosslinking agent.

  As the binder resin of the resin fine particles in the present invention, a polyester resin can also be used. Of these, those having an acid value (according to JIS K 0070) in the range of 1 to 50 (KOH mg / g) are preferred, and those in the range of 3 to 30 are more preferred. If the acid value is 1 or less, it is difficult to obtain a stable aqueous dispersion. On the other hand, if it exceeds 50, the amount of water absorbed by the toner increases, which is not preferable. The acid value of the polyester resin can be adjusted by changing the composition ratio of the acid component and the alcohol component or by neutralizing the acid value with alcohol.

  In the present invention, in order to produce fine particles using the above polyester resin having an acid value, an oil phase in which a pigment is dispersed and the polyester resin is dissolved in a suitable organic solvent is prepared, and a neutralizing agent is added thereto. It is obtained by adding and ionizing the carboxyl group of the polyester resin, then adding it to an aqueous medium to invert the phase, and distilling off the solvent. In the oil phase, an internal substance such as a wax or a charge control agent may be dispersed as necessary. The fine particles obtained in this manner are formed by preferentially gathering ionically high acid value polyesters on the particle surfaces and pushing wax or low acid value polyesters into the particles.

  The polyester resin used as the binder resin is produced by subjecting a polyhydric alcohol component and a polyvalent carboxylic acid component as polymerization monomers to a polycondensation reaction in the presence of a catalyst, if necessary. Examples of the polyhydric alcohol component of the polymerization monomer include polyoxypropylene (2,2) -2,2-bis (4-hydroxyphenyl) propane, polyoxypropylene (3,3) -2,2- Bis (4-hydroxyphenyl) propane, polyoxyethylene (2,0) -2,2-bis (4-hydroxyphenyl) propane, polyoxypropylene (2,0) -polyoxyethylene (2,0) -2 Diols such as 1,2-bis (4-hydroxyphenyl) propane, polyoxypropylene (2,0) -polyoxyethylene (2,0) -2,2-bis (4-hydroxyphenyl) propane; ethylene glycol, diethylene glycol , Triethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, isopen Glycol, hydrogenated bisphenol A, 1,3-butanediol, 1,4-butanediol, neopentyl glycol, xylylene glycol, 1,4-cyclohexanedimethanol, glycerin, trimethylolethane, trimethylolpropane, pentaerythritol Bis- (β-hydroxyethyl) terephthalate, tris- (β-hydroxyethyl) isocyanurate, 2,2,4-trimethylolpentane-1,3-diol and the like are used. Furthermore, as a hydroxycarboxylic acid component, for example, p-oxybenzoic acid, vanillic acid, dimethylolpropionic acid, malic acid, tartaric acid, 5-hydroxyisophthalic acid and the like can be added.

  Examples of the polyvalent carboxylic acid component include malonic acid, succinic acid, glutaric acid, dimer acid, phthalic acid, isophthalic acid, terephthalic acid, isophthalic acid dimethyl ester, terephthalic acid dimethyl ester, terephthalic acid monomethyl ester, and tetrahydroterephthalic acid. , Methyltetrahydrophthalic acid, hexahydrophthalic acid, dimethyltetrahydrophthalic acid, endomethylenehexahydrophthalic acid, naphthalenetetracarboxylic acid, diphenolic acid, trimellitic acid, pyromellitic acid, trimesic acid, cyclopentanedicarboxylic acid, 3, 3 ′, 4,4′-benzophenonetetracarboxylic acid, 1,2,3,4-butanetetracarboxylic acid, 2,2-bis- (4-carboxyphenyl) propane, trimellitic anhydride and 4,4- Diaminophenyl meta Obtained from a trimerization reaction product of diimide carboxylic acid, tris- (β-carboxyethyl) isocyanurate, isocyanurate ring-containing polyimide carboxylic acid, tolylene diisocyanate, xylylene diisocyanate or isophorone diisocyanate and trimellitic anhydride Examples include isocyanate ring-containing polyimide carboxylic acid. These may be used alone or in admixture of two or more.

  Among these, when a trivalent or higher polyvalent carboxylic acid and a polyhydric alcohol are used, a crosslinked polyester resin is generated, and thus stability such as fixing strength and offset resistance can be improved. A desired polyester resin can be easily produced by polycondensation using these as raw materials by a conventionally known ordinary method.

  The binder resin used in the toner of the present invention is preferably a resin for color toners that is excellent in transparency and color developability. Furthermore, in terms of toner fixability and particle formability, at least the polyester resin obtained by the above method. Among them, two or more different Tg or acid values may be mixed.

  The binder resin used in the present invention may be combined with other resins in the polyester resin. Other resins include styrene resin, acrylic resin, styrene-acrylic resin, silicone resin, epoxy resin, diene resin, phenol resin, terpene resin, coumarin resin, amide resin, amideimide resin, butyral resin, urethane resin, ethylene Examples include vinyl acetate resin.

  In the present invention, the polyester resin in the toner material is dissolved in a soluble organic solvent. The organic solvent used depends on the constituent components of the polyester, but usually, hydrocarbons such as toluene, xylene and hexane, halogenated hydrocarbons such as methylene chloride, chloroform and dichloroethane, ethanol, butanol and benzyl alcohol ether And alcohols such as tetrahydrofuran, ethers, esters such as methyl acetate, ethyl acetate, butyl acetate and isopropyl acetate, and ketones such as acetone, methyl ethyl ketone, diisobutyl ketone, cyclohexanone and methylcyclohexanone. These organic solvents mainly dissolve the polyester resin, but the colorant and other additives may not be dissolved.

  The volume average particle diameter of the binder resin in the resin particle dispersion is preferably 1 μm or less, and more preferably 0.01 μm or more and 1 μm or less. When the volume average particle size exceeds 1 μm, the particle size distribution of toner particles obtained by agglomeration and fusion may be broadened, or free particles may be generated, leading to a decrease in toner performance and reliability. In the present invention, by setting the volume average particle size to 1 μm or less, it is possible to improve the dispersion of the resin fine particles in the agglomerated particles, to suppress the uneven distribution of the composition among the toner particles, and to vary the toner performance and reliability. There is an advantage that it can be kept low. The volume average particle diameter can be measured with, for example, a laser diffraction particle size distribution measuring machine or a Coulter counter.

  Moreover, as said binder resin, it is preferable to use the thing whose glass transition temperature (Tg) measured by DSC (differential scanning calorimeter) is the range of 40-70 degreeC. This glass transition temperature can be adjusted by changing the composition ratio of the constituent monomers. The peak molecular weight of the binder resin is preferably in the range of 5000 to 30000. If the peak molecular weight is less than 5000, fine particles cannot be obtained by drying, or the toner is too meltable and color mixing occurs between pixels. On the other hand, if the peak molecular weight exceeds 30000, the oil phase becomes highly viscous, or the viscosity of the toner at the time of fixing becomes too high, and a low temperature offset occurs in the fixing step, which is not preferable.

  Further, when the Mw (weight average molecular weight) / Mn (number average molecular weight) of the binder resin in the resin fine particles exceeds 100, the molecular weight distribution of the binder resin becomes too wide, so that sufficient fixing is performed. It will disappear.

[Colorant]
The colorant used in the present invention is added together with the binder resin as a toner material and dispersed in the fine particles. Further, the colorant may be incorporated by heteroaggregation during the particle growth process. As the colorant, known organic pigments, inorganic pigments or dyes are used. Among the color toners used in the present invention, yellow toner is used as the colorant in the colorant particles. Y. 49, 65, 73, 74, 75, 97, 98, 111, 116, 130 are preferably included. Similarly, in magenta toner, P.I. R. 31, 32, 122, 146, 147, 150, 164, 170, 175, 176, 184, 185, 187, 188, 208, 210, 212, 213, 222, 238, 245, 253, 256, 258, 261, Preferably, at least one of 269 is included. For cyan toner, C.I. I. Pigment blue 15: 1, C.I. I. Pigment Blue 15: 3 is preferable. In the case of the black toner, a mixture of carbon black, metal complex salt, and the like can be given.

  By using the colorant in consideration of the charge control agent, the scattering of the image at the time of fixing is reduced although the mechanism is not clear. These colorants need to be contained in a ratio that can form a visible image having a sufficient density, and vary depending on the toner particle size, development amount, etc., but usually 1 per 100 parts by mass of toner. It is -100 mass parts, Preferably it is the range of 2-20 mass parts.

  The colorant preferably has a volume average particle size of 1 μm or less, more preferably 0.5 μm or less, and still more preferably 0.01 μm or more and 0.5 μm or less. When the volume average particle size exceeds 1 μm, the particle size distribution of the finally obtained color toner may be broadened, free particles may be easily generated, and the toner performance and reliability may be reduced. It may be easy to invite.

  On the other hand, by setting the volume average particle size to 1 μm or less, the dispersion to the colorant in the agglomerated particles is improved, the uneven distribution of the composition among the toner particles is suppressed, and the variation in toner performance and reliability is suppressed to a low level. There is an advantage that can be easily done. Further, by setting the volume average particle size to 0.5 μm or less, the color developability, color reproducibility, OHP permeability and the like of the color toner can be further improved. In addition, the said volume average particle diameter can be measured using a laser diffraction type particle size distribution analyzer etc., for example. Further, the content of the colorant in the aggregated particles is preferably 50% by mass or less, and more preferably 2% by mass or more and 20% by mass or less.

[Release agent]
Any releasing agent may be used as long as it has releasability. Specifically, for waxes and waxes, plant systems such as carnauba wax, cotton wax, wood wax, rice wax, etc. Animal waxes such as wax, beeswax and lanolin, mineral waxes such as ozokerite and cercin, and petroleum waxes such as paraffin, microcrystalline and petrolatum can be used.

  In addition to these natural waxes, synthetic hydrocarbon waxes such as Fischer-Tropsch wax and polyethylene wax, fatty acid amides such as 12-hydroxystearic acid amide, stearic acid amide, phthalic anhydride imide, and chlorinated hydrocarbon, esters, Synthetic waxes such as ketones and ethers can also be used. In addition, as a low molecular weight crystalline polymer resin, a homopolymer or copolymer of polyacrylate such as poly n-stearyl methacrylate and poly n-lauryl methacrylate (for example, a copolymer of n-stearyl acrylate-ethyl methacrylate, etc.) And the like, and a crystalline polymer compound having a long-chain alkyl group as a side chain, such as petroleum wax or synthetic wax such as paraffin wax and microcrystalline wax is preferable.

  The volume average particle size of the release agent in the dispersion is preferably 2 μm or less, more preferably 0.1 to 1.5 μm.

  When the volume average particle diameter of the release agent in the dispersion exceeds 2 μm, the particle size distribution of the finally obtained electrostatic charge developing toner becomes wide, and free particles may be easily generated. In some cases, the reliability is likely to decrease.

  In the present invention, by adjusting the volume average particle diameter of the release agent in the dispersion to the above range, uneven distribution of the composition among the toner particles can be suppressed, and variation in toner performance and reliability can be suppressed low. There is an advantage that can be. In addition, the said volume average particle diameter can be measured using a laser diffraction type particle size distribution measuring machine, a centrifugal type particle size distribution measuring machine, etc., for example.

[Charge control agent]
As the charge control agent used in the present invention, a commonly used positive charge property or negative charge property charge control agent can be used. As the charge control agent, a metal soap can be used in combination. Such metal soaps include aluminum tristearate, aluminum distearate, barium, calcium, lead and zinc stearate, or cobalt, manganese, lead and zinc linolenate, aluminum, calcium, cobalt octanoic acid Salts, calcium and cobalt oleates, zinc palmitate, calcium, cobalt, manganese, lead and zinc naphthenates, calcium, cobalt, manganese lead and zinc resins and the like can be used. In addition, a metal complex of an organic compound having a carboxyl group or a nitrogen-containing group, a metal-containing dye, nigrosine, and the like can be given. In addition, a compound selected from the group consisting of metal salts of benzoic acid, salicylic acid, alkylsalicylic acid or catechol, metal-containing bisazo dyes, tetraphenylborate derivatives, alkylpyridinium salts, and combinations of these as appropriate. Is also possible. Specifically, Spiron Black TRH (Hodogaya Chemical Co., Ltd.), T-77 (Hodogaya Chemical Co., Ltd.), Bontron S-34 (Orient Chemical Co., Ltd.), Bontron E-84 (Orient Chemical Co., Ltd.), Bontron Examples thereof include charge control resins such as N-01 (manufactured by Orient Chemical Co., Ltd.), copy blue-PR (manufactured by Hoechst), quaternary ammonium salt-containing resins, and polar resins containing sulfur atoms. The counter ion of the charge control agent is not particularly limited, and any one can be used. For example, there are hydrogen, lithium, sodium, potassium, ammonium, alkylammonium and the like.

Further, the charge control agent used in the present invention is preferably a compound represented by the general formula (I) or (II) or a metal compound thereof. In the general formula (I) or (II), A, A ¹ , A ² , R, R ¹ and R ² represent aromatic ring residues which may have a substituent, and are the same or different. May be. Here, the aromatic ring means a carbocyclic ring (referring to a cyclic carbon-carbon conjugated double bond system), a heterocyclic ring or carbocyclic rings, a heterocyclic ring, or a condensed carbocyclic ring and a heterocyclic ring.

（式中、環ＡおよびＲは、それぞれ置換基を有していてもよい芳香族環残基を表し、−ＯＨと−ＣＯＮＨ−Ｒは芳香族環残基Ａ上で相隣る置換位置に結合している。）

(In the formula, each of rings A and R represents an aromatic ring residue which may have a substituent, and —OH and —CONH—R are adjacent to each other on the aromatic ring residue A. Combined.)

（式中、Ａ¹、Ａ²、Ｒ¹およびＲ²は、それぞれ置換基を有していてもよい芳香族環残基を表し、Ｂは２価の有機基を表す。また、式中の−ＯＨと−ＣＯＮＨ−Ｒ¹および−ＯＨと−ＣＯＮＨ−Ｒ²は芳香族環残基Ａ¹、Ａ²上で相隣る置換位置に結合している。）

(In the formula, A ¹ , A ² , R ¹ and R ² each represent an aromatic ring residue which may have a substituent, and B represents a divalent organic group. -OH and -CONH-R ¹ and -OH and -CONH-R ² is attached to the Aitonaru substitution positions on the aromatic ring residue a ^1, a ^2.)

Specific examples of such aromatic rings include benzene ring, naphthalene ring, anthracene ring, phenanthrene ring, carbazole ring, fluorene ring, fluorenone ring, dibenzofuran ring, dibenzothiophene ring, benzocarbazole ring, and preferably A benzene ring and a naphthalene ring. More preferably, A, A ¹ and A ² are naphthalene rings, and R, R ¹ and R ² are each a benzene ring or a naphthalene ring. Specific examples of the substituent that may be present on the aromatic ring include alkyl groups such as a methyl group, an ethyl group, a propyl group, an n-butyl group, and a tert-butyl group; a haloalkyl such as a trifluoromethyl group. Group; a halogen atom such as a chlorine atom or a bromine atom may be mentioned, and a chlorine atom or a trifluoromethyl group is more preferable. The number of substitutions is preferably 1 to 5, and when plural, the substituents may be the same or different from each other.

  In the general formula (II), B represents a divalent organic group which may have a substituent. Specific examples include a methylene group, an ethylene group, a trimethylene group, a cyclohexylene group, and the like. Is a methylene group. Specific examples of the substituent include a methyl group, an ethyl group, a propyl group, a phenyl group, and the like, and preferably unsubstituted. The metal element of the metal compound of the compound represented by the general formula (I) or (II) is not particularly limited, but is preferably an alkali metal salt, an alkaline earth metal salt, an aluminum compound, or a boron compound, and more preferable. Examples include potassium salts, aluminum compounds, and boron compounds. Particularly preferred is a potassium salt. Furthermore, the content of potassium is preferably 0.5 mol or less, most preferably 0.001 to 0.3 mol, relative to 1 mol of the compound represented by the general formula (I) or (II). Among the compounds represented by the general formula (I) or (II), specific examples of suitable compounds include the following compounds or potassium salts thereof, but are not limited thereto.

  Examples of the method for dispersing these compounds in water include the following methods. Nonionic surfactants typified by polyoxyethylene alkylphenyl ethers, anionic surfactants typified by alkylbenzene sulfonates, and cationic surfactants typified by quaternary ammonium salts, etc. It can be easily prepared by adding a compound represented by the formula (I) or (II) or a metal salt thereof in water and using a mechanical pulverization method in which a medium or the like is added. The dispersion diameter is optimally 0.01-1 μm. When the dispersion diameter is less than 0.01 μm, the charge control ability decreases. Further, when the dispersion diameter is larger than 1 μm, it is difficult to uniformly charge the toner. Furthermore, these compounds may be used alone or in combination of two or more.

[Polar resin containing sulfur atoms]
In addition, a polar resin having a sulfur atom can be added as a charge control agent to the toner of the present invention. Among polar resins having a sulfur atom, it is particularly preferable to use a polymer having a sulfonic acid group.

Specifically, it is a copolymer composed of a vinyl monomer and SO ₃ X (X = H, alkali metal) group-containing (meth) acrylamide (hereinafter sometimes referred to as sulfonic acid acrylamide), and The weight average molecular weight is 10,000 to 30,000, and has charge control performance. By adding a polymer having a sulfonic acid group to the toner, the dispersion state of the wax in the binder is improved, the fixability on the low temperature side and the high temperature side is dramatically improved, and the deterioration of the charging property due to the wax is prevented. be able to. Furthermore, since the polarity of the sulfonic acid group also improves the chargeability of the toner, scattering that occurs during fixing can be sufficiently suppressed, and the image density and fog are also improved.

  Examples of the polymer having a sulfonic acid group used in the present invention include a polymer type compound having a sulfonic acid group in the side chain, and in particular, a methacrylic acid monomer containing a sulfonic acid group has a copolymerization ratio of 2 mass. % Or more, preferably 5% by mass or more, and a polymer compound comprising a styrene and / or styrene (meth) acrylate copolymer having a glass transition temperature of 40 to 90 ° C. is used in the toner particles. The preferred charging characteristics can be enjoyed without affecting the required thermal characteristics.

  As said (sulfonic) group containing (meth) acrylamide type monomer, what can be represented by following General formula (2) is preferable, and, specifically, 2-acrylamido-2-methylpropanoic acid and 2-methacrylamide-2-methyl are used. And propanoic acid.

［上記一般式（２）中、Ｒ₁は水素原子、又はメチル基を示し、Ｒ₁とＲ₃は、それぞれ水素原子、Ｃ１〜Ｃ１０のアルキル基、アルケニル基、アリール基、又はアルコキシ基を示し、ｎは１〜１０の整数を示す。］

[In the general formula (2), R ₁ represents a hydrogen atom or a methyl group, and R ₁ and R ₃ represent a hydrogen atom, a C1-C10 alkyl group, an alkenyl group, an aryl group, or an alkoxy group, respectively. , N represents an integer of 1-10. ]

(Vinyl monomer in polar resin)
Representative examples of vinyl monomers copolymerized with sulfonic acid acrylamide include vinyl aromatic hydrocarbon monomers and (meth) acrylate monomers.

  The vinyl aromatic hydrocarbon monomer is a compound having a structure in which a vinyl group is bonded to an aromatic hydrocarbon. Specific examples include styrene, α-methylstyrene, 2-methylstyrene, 3-methylstyrene, 4 -Methylstyrene, 2-ethylstyrene, 3-ethylstyrene, 4-ethylstyrene, 2-propylstyrene, 3-propylstyrene, 4-propylstyrene, 2-isopropylstyrene, 3-isopropylstyrene, 4-isopropylstyrene, 2 -Chlorostyrene, 3-chlorostyrene, 4-chlorostyrene, 2-methyl-α-methylstyrene, 3-methyl-α-methylstyrene, 4-methyl-α-methylstyrene, 2-ethyl-α-methylstyrene, 3-ethyl-α-methylstyrene, 4-ethyl-α-methylstyrene, 2-propyl-α-methyl Tylstyrene, 3-propyl-α-methylstyrene, 4-propyl-α-methylstyrene, 2-isopropyl-α-methylstyrene, 3-isopropyl-α-methylstyrene, 4-isopropyl-α-methylstyrene, 2-chloro -Α-methylstyrene, 3-chloro-α-methylstyrene, 4-chloro-α-methylstyrene, 2,3-dimethylstyrene, 3,4-dimethylstyrene, 2,4-dimethylstyrene, 2,6-dimethyl Styrene, 2,3-diethylstyrene, 3,4-diethylstyrene, 2,4-diethylstyrene, 2,6-diethylstyrene, 2-methyl-3-ethylstyrene, 2-methyl-4-ethylstyrene, 2- Chloro-4-methylstyrene, 2,3-dimethyl-α-methylstyrene, 3,4-dimethyl-α-methylstyrene, , 4-dimethylstyrene, 2,6-dimethyl-α-methylstyrene, 2,3-diethyl-α-methylstyrene, 3,4-diethyl-α-methylstyrene, 2,4-diethyl-α-methylstyrene, 2,6-diethyl-α-methylstyrene, 2-ethyl-3-methyl-α-methylstyrene, 2-methyl-4-propyl-α-methylstyrene, 2-chloro-4-ethyl-α-methylstyrene, etc. Is mentioned. These vinyl aromatic hydrocarbon monomers may be used alone or in combination of two or more.

  Specific examples of the (meth) acrylate monomer include methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, n-amyl acrylate, and isoamyl acrylate. Acrylic acid esters such as n-hexyl acrylate, 2-ethylhexyl acrylate, hydroxypropyl acrylate, lauryl acrylate; methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, Methacrylic acid esters such as isobutyl methacrylate, n-amyl methacrylate, isoamyl methacrylate, n-hexyl methacrylate, 2-ethylhexyl methacrylate, hydroxypropyl methacrylate, lauryl methacrylate And the like. These (meth) acrylate monomers may be used alone or in combination of two or more.

[Sulphonic acid acrylamide in polar resin]
As SO ₃ X (X = H, alkali metal) group-containing (meth) acrylamide, ie, sulfonic acid group or sulfonate group-containing (meth) acrylamide, 2-acrylamide-2-methylpropanesulfonic acid, 2-acrylamide- n-butanesulfonic acid, 2-acrylamide-n-hexanesulfonic acid, 2-acrylamide-n-octanesulfonic acid, 2-acrylamide-n-dodecanesulfonic acid, 2-acrylamide-n-tetradecanesulfonic acid, 2-acrylamide- 2-methylpropanesulfonic acid, 2-acrylamido-2-phenylpropanesulfonic acid, 2-acrylamido-2,2,4-trimethylpentanesulfonic acid, 2-acrylamido-2-methylphenylethanesulfonic acid, 2-acrylamide-2 -(4-chloro Phenyl) propanesulfonic acid, 2-acrylamido-2-carboxymethylpropanesulfonic acid, 2-acrylamido-2- (2-pyridine) propanesulfonic acid, 2-acrylamido-1-methylpropanesulfonic acid, 3-acrylamido-3- Examples thereof include acids such as methylbutanesulfonic acid, 2-methacrylamide-n-decanesulfonic acid and 4-methacrylamideamidobenzenesulfonic acid, or metal salts such as sodium salt and potassium salt of these acids. These may be used alone or in combination of two or more.

  The charge control agent is used in an amount of 0.01 to 10 parts by weight, more preferably 0.05 to 5 parts by weight, based on 100 parts by weight of the toner base particles. When the addition amount is less than 0.01 parts by mass, the charging ability is not sufficiently obtained, and voids are likely to occur from the initial image. When the amount exceeds 10 parts by mass, dispersion of the charge control agent itself is poor and the retained charge amount becomes excessive, and the object of producing a toner that eliminates the peeling offset at the time of fixing cannot be achieved. If the toner of the present invention is a polymerization method, a charge control agent may be contained in either the water phase or the oil phase.

[Measurement method of toner particle size]
The volume average particle size of the toner of the present invention is measured by particle size distribution analysis by the Coulter method. As the measuring device, Coulter Counter TA-II or Coulter Multisizer II (manufactured by Coulter Inc.) is used. The measurement is performed using an electrolytic solution. As the electrolytic solution, an electrolytic solution in which about 1% NaCl aqueous solution is prepared using primary sodium chloride can be used. For example, ISOTON-II (manufactured by Coulter Scientific Japan) can be used. As a measurement method, 0.1 to 5 ml of a surfactant (preferably alkylbenzene sulfonate) is added as a dispersant to 100 to 150 ml of the electrolytic aqueous solution, and 2 to 20 mg of a measurement sample is further added. The electrolytic solution in which the sample is suspended is subjected to a dispersion treatment with an ultrasonic disperser for about 1 to 3 minutes, and then the volume and the number of toner particles are measured in each channel by using the measurement apparatus with a 100 μm aperture. Then, the toner volume distribution and number distribution are calculated. Then, the number average particle diameter (D1) obtained from the toner particle number distribution and the weight-based toner weight average particle diameter (D4) obtained from the toner particle volume distribution (the median value of each channel is the representative value for each channel). Value). As channels, 2.00 to 2.52 μm; 2.52 to 3.17 μm; 3.17 to 4.00 μm; 4.00 to 5.04 μm; 5.04 to 6.35 μm; 6.35 to 8. 00 μm; 8.00 to 10.08 μm; 10.08 to 12.70 μm; 12.70 to 16.00 μm; 16.00 to 20.20 μm; 20.20 to 25.40 μm; 25.40 to 32.00 μm; 13 channels of 32.00-40.30 μm are used. Through the above operation, the volume average particle diameter of the color toner was measured.

[Molecular weight distribution]
The molecular weight and molecular weight distribution of the binder resin contained in the toner particles are measured by the following method. The column is stabilized in a 40 ° C. heat chamber, and THF as a solvent is allowed to flow through the column at this temperature at a flow rate of 1 ml per minute, and about 100 μl of the THF sample solution is injected and measured. In measuring the molecular weight of the sample, the molecular weight distribution of the sample was calculated from the relationship between the logarithmic value of the calibration curve prepared from several monodisperse polystyrene standard samples and the number of counts. As a standard polystyrene sample for preparing a calibration curve, for example, one having a molecular weight of about 10 ² to 10 ⁷ manufactured by Tosoh Corporation or Showa Denko KK, and at least about 10 standard polystyrene samples is suitable. is there. An RI (refractive index) detector is used as the detector. As the column, it is preferable to combine a plurality of commercially available polystyrene gel columns. For example, a combination of shodex GPC KF-801, 802, 803, 804, 805, 806, 807, 800P manufactured by Showa Denko KK TSKgel G1000H (H) (L), G2000H (H) (L), G3000H (H) (L), G4000H (H) (L), G5000H (H) (L), G6000H (H) (L), G7000H (H) (L) and the combination of TSK guard column can be mentioned.

  Moreover, a sample is produced as follows. Place the sample in THF and let stand for several hours, then shake well and mix well with THF (until the sample is no longer united) and let stand for more than 12 hours. At this time, the standing time in THF is set to be 24 hours or longer. Thereafter, a sample processing filter (pore size 0.45 to 0.5 μm, for example, Mysori Disc H-25-5 manufactured by Tosoh Corporation, Excro Disc 25CR manufactured by Gelman Science Japan Co., Ltd., etc.) can be used. A sample of GPC is used. The sample concentration is adjusted so that the resin component is 0.5 to 5 mg / ml. Through the above operation, the peak molecular weight of the binder resin in the color toner and the ratio Mw / Mn between the weight average molecular weight Mw and the number average molecular weight Mn were determined.

[Viscoelasticity]
As a means for knowing the fixing characteristics of the color toner, there is a method for knowing viscoelasticity using a strain control rheometer such as ARES (Rheometric Scientific F.E.). Here, the value obtained by the rheometer is considered to be a thermal characteristic in the binder part of the toner.

  Under the following conditions, storage elastic modulus G ′ and loss elastic modulus G ″ in a temperature range of 60 to 200 ° C. were measured, and tan δ = G ′ / G ″ was measured.

  As the measuring device, a rotating plate type rheometer ARES (trade name, manufactured by TA INSTRUMENTS) is used. The measurement sample was a disk-shaped sample of toner with a diameter of 7.9 mm and a thickness of 2.0 ± 0.3 mm, which was press-molded with a tablet molding machine at 25 ° C., mounted on a parallel plate, and room temperature ( 25 ° C.) to 120 ° C. over 15 minutes to adjust the shape of the disc, and then cool to the measurement start temperature of viscoelasticity to start measurement. In particular, it is important to set the sample so that the initial normal force becomes 0. As described below, in the subsequent measurement, the automatic tension adjustment (Auto Tension Adjustment ON) is set to normal. Force effects can be canceled.

The measurement is performed under the following conditions.
1. A parallel plate with a diameter of 7.9 mm is used.
2. The frequency (Frequency) is 1.0 Hz.
3. The applied strain initial value (Strain) is set to 0.1%.
4. Measure between 30 and 200 ° C at a ramp rate of 2.0 ° C / min.

  In the measurement, the following automatic adjustment mode setting conditions are used.

Measurement is performed in an automatic strain adjustment mode (Auto Strain).
5. The maximum strain (Max Applied Strain) is set to 20.0%.
6). The maximum torque (Max Allowed Torque) is set to 200.0 g · cm, and the minimum torque (Min Allowed Torque) is set to 0.2 g · cm.
7). Distortion adjustment (Strain Adjustment) 20.0% of Cur r
Set to ent Strain.

In the measurement, an automatic tension adjustment mode (Auto Tension) is adopted.
8). Automatic tension direction (Auto Tension Direction)
Is set as a compression.
9. 9. Initial Static Force (Initial Static Force)
0g, automatic tension sensitivity (Auto Tension Sensit
ivity) is set to 40.0 g.
10. The operating condition of the automatic tension (Sample Tension) is 1.0 × 10 ³ (Pa) or more.

  In the color toner of the present invention, the tangent value tan δ of dynamic viscoelasticity is preferably in the range of 0.5 to 25 at 100 ° C. or higher. When tan δ is 0.5 or less, the viscosity of the toner becomes low, so that the recording material is easily wound around the fixing member during fixing. When tan δ is 2.5 or more, the elasticity of the toner is strong. At this time, if the toner holding charge amount is low, a peeling offset at the time of fixing tends to occur.

[Toner charge amount]
The measurement of the triboelectric charge amount of the color toner is performed as follows. First, 50 to 100 ml of a mixture of a ferrite carrier having a volume average particle diameter of 50 μm coated with 1% of polymethyl methacrylate (Powder Tech Co.) and a toner having a weight ratio of 19: 1 to be measured for triboelectric charge is made of 50 to 100 ml of polyethylene. And shake by hand for about 10-40 seconds. Next, about 0.5 to 1.5 g of the mixture (developer) is placed in a metal measuring container having a 500 mesh screen at the bottom, and a metal lid is placed. The weight of the entire measurement container at this time is W ₁ g. Next, in the suction machine (at least the insulator is in contact with the measuring instrument), the pressure of the vacuum gauge is set to 250 mmAq by suction from the suction port and adjusting the air volume control valve. In this state, the toner is removed by suction for 2 minutes. The potential of the electrometer at this time is set to V. The capacity of the capacitor is C (μF). Further, the weight of the entire measurement container after the suction is measured and is defined as W ₂ (g). The triboelectric charge amount (μC / g) of the toner is calculated as follows.
Charge amount of toner [μC / g] = C × V / (W ₁ −W ₂ )
(However, the measurement conditions are 23 ° C. and 50% RH)

  When the color toner of the present invention is measured by the above method, the triboelectric charge amount is desirably -40 [μC / g] to -10 [μC / g]. More preferably, it is −30 [μC / g] to −15 [μC / g].

  In the color toner of the present invention, the glass transition temperature (Tg) is preferably in the range of 40 to 70 ° C. When Tg is 40 ° C. or less, the color toner mixture between pixels proceeds excessively during fixing. Further, when Tg is 70 ° C. or higher, the elasticity of the toner is strong, and when the toner holding charge amount is low at this time, peeling offset at the time of fixing tends to occur.

[Manufacturing developer, measuring various physical properties, and evaluating image quality]
EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples. However, the present invention is not limited only to these examples. Parts and% are based on mass unless otherwise specified.

[Preparation of resin dispersion A]
Styrene: 300 parts Butyl acrylate: 80 parts Acrylic acid: 8 parts Dodecyl mercaptan: 4 parts The above components are mixed in advance and dissolved to prepare a solution (a). On the other hand, 7 parts of nonionic surfactant (trade name: Novonil, Sanyo Kasei Co., Ltd.) and 10 parts of anionic surfactant (trade name: Neogen R, Daiichi Kogyo Seiyaku Co., Ltd.) are added to 520 parts of ion-exchanged water. Dissolve to prepare solution (b). The solutions (a) and (b) were put into a flask, emulsified by dispersing, and slowly mixed for 10 minutes. Further, 50 parts of ion-exchanged water in which 3 parts of ammonium persulfate was dissolved was added to perform nitrogen substitution. Thereafter, while stirring the flask, the contents were heated in an oil bath until the content reached 70 ° C., and emulsion polymerization was continued for 6 hours. Then, this reaction liquid was cooled to room temperature, and a resin dispersion A having a volume average particle size: 152 nm and a peak average molecular weight: 15000 was obtained.

[Preparation of resin dispersion B]
Polyester (2 mol of propylene oxide adduct of bisphenol A / 3 mol adduct of propylene oxide of bisphenol A / 5.5 mol adduct of phenol novolac / ethylene oxide / terephthalic acid / trimellitic anhydride / dimethyl terephthalate polycondensate): 200 parts Tetrahydrofuran: 280 parts Polyethylene glycol: 20 parts Ion exchange water: 500 parts The above components are mixed in advance and dissolved to prepare a solution, which is dispersed for 15 minutes with a rotor-stator homogenizer (trade name: Ultra Turrax, manufactured by IKA). Then, the temperature was raised and the mixture was left at 80 ° C. for 4 hours. Thereafter, the mixture was cooled to obtain a resin dispersion B having a volume average particle size of 180 nm and a peak average molecular weight of 12,000.

[Preparation of resin dispersion C]
Styrene: 300 parts butyl acrylate: 80 parts acrylic acid: 8 parts dodecyl mercaptan: 4 parts divinylbenzene: 2 parts The above components are mixed in advance and dissolved to prepare a solution (a). On the other hand, 7 parts of nonionic surfactant (trade name: Novonil, Sanyo Kasei Co., Ltd.) and 10 parts of anionic surfactant (trade name: Neogen R, Daiichi Kogyo Seiyaku Co., Ltd.) are added to 520 parts of ion-exchanged water. Dissolve to prepare solution (b). The solutions (a) and (b) were put into a flask, emulsified by dispersing, and slowly mixed for 10 minutes. Further, 50 parts of ion-exchanged water in which 3 parts of ammonium persulfate was dissolved was added to perform nitrogen substitution. Thereafter, while stirring the flask, the contents were heated in an oil bath until the content reached 70 ° C., and emulsion polymerization was continued for 6 hours. Then, this reaction liquid was cooled to room temperature, and a resin dispersion A having a volume average particle size: 152 nm and a peak average molecular weight: 50000 was obtained.

[Preparation of resin dispersion D]
Polyester (polycondensate of bisphenol A propylene oxide 2 mol adduct 100 parts / terephthalic acid 20 parts / isophthalic acid 20 parts / dodecenyl succinic acid 60 parts): 200 parts tetrahydrofuran: 280 parts polyethylene glycol: 5 parts ion-exchanged water: 500 parts The above components were mixed and dissolved in advance to prepare a solution, which was dispersed for 15 minutes with a rotor-stator homogenizer (trade name: Ultra Tarrax, manufactured by IKA), then heated to stand at 80 ° C. for 4 hours. Thereafter, the mixture was cooled to obtain a resin dispersion B having a volume average particle size of 180 nm and a peak average molecular weight of 4000.

[Preparation of Colorant Dispersion A]
Colorant P.I. Y. 74 (Fast Yellow SG: Sanyo Color Co., Ltd.): 70 parts anionic surfactant (trade name: Neogen, manufactured by Daiichi Kogyo Co., Ltd.): 3 parts Ion-exchanged water: 400 parts After mixing and dissolving the above components, Dispersion was performed using a homogenizer (manufactured by IKA, Ultra Tarrax) to obtain a colorant dispersion A in which a colorant having a volume average particle size of 150 nm was dispersed.

[Preparation of release agent dispersion A]
Polyethylene wax (trade name: POLYWAX655, melting point 93 ° C., manufactured by Toyo Petrolite Co., Ltd.): 100 parts anionic surfactant (trade name: Pionin A-45-D, manufactured by Takemoto Yushi Co., Ltd.): 2 parts Ion-exchanged water: 500 parts After the components are mixed and dissolved, they are dispersed using a homogenizer (IKA, Ultra Tarrax), then dispersed with a pressure discharge type homogenizer, and release agent fine particles having a volume average particle size of 280 nm (polyethylene wax). ) Was dispersed to obtain a release agent dispersion (1).

[Charge control agent fine particle dispersion A]
Sand grinder 20 parts of 4,4′-methylenebis [2- [N- (4-chlorophenyl) amide] -3-hydroxynaphthalene] (compound CA1 having the following structure), 4 parts of alkylnaphthalene sulfonate and 76 parts of demineralized water Dispersion was performed with a mill to obtain a charge control agent fine particle dispersion. The average particle size measured by UPA was 200 nm.

[Charge control agent fine particle dispersion B]
Among the polar resins having a sulfur atom, the weight average molecular weight comprising a vinyl monomer and SO ₃ X (X = H, alkali metal) group-containing (meth) acrylamide (hereinafter sometimes referred to as sulfonic acid acrylamide) is 10 parts of 20000 copolymer (CA2), 4 parts of alkylnaphthalene sulfonate and 76 parts of demineralized water were dispersed in a sand grinder mill to obtain a charge control agent fine particle dispersion. The average particle size measured by UPA was 200 nm.

[Toner Production Example 1]
Resin dispersion A: 300 parts Colorant dispersion A: 200 parts Release agent dispersion A: 100 parts Charge control agent fine particle dispersion A: 5 parts Rosin-modified maleic acid (softening point 139 ° C.): 60 parts (8 mass) %)
Cationic surfactant (trade name: Sanizol B50, manufactured by Kao Corporation): 3 parts Ion exchange water: 500 parts The above components were homogenized in a round bottom stainless steel flask (trade name: Ultra Turrax T50, manufactured by IKA). After mixing and dispersing to prepare a mixed solution, the mixture was heated to 50 ° C. with stirring in an oil bath for heating, and held at 50 ° C. for 30 minutes to form aggregated particles. When a part of the obtained aggregated particles was observed with an optical microscope, the volume average particle diameter of the aggregated particles was about 5.1 μm.

  50 parts of the resin dispersion A was gradually added to the liquid in which the aggregated particles were formed, and the mixture was further heated and stirred at 50 ° C. for 30 minutes to obtain an aggregated particle dispersion A. When the obtained aggregated particle dispersion A was observed with an optical microscope, the volume average particle diameter of the aggregated particles was about 5.7 μm.

  Next, 6 parts of sodium dodecylbenzenesulfonate (trade name: Neogen SC, manufactured by Daiichi Kogyo Co., Ltd.) as an anionic surfactant is added to the aggregated particle dispersion A, heated to 97 ° C., and held for 7 hours. Then, the aggregated particles were fused. Thereafter, it was cooled to 45 ° C. at a descending rate of 1.0 ° C./min, filtered, sufficiently washed with ion-exchanged water, and further filtered through a 400 mesh sieve. When the volume average particle diameter of the fused particles was measured with a Coulter counter, it was 5.8 μm. This was dried with a vacuum dryer to obtain yellow toner particles A.

  To 100 parts of the obtained toner particles A, 2.0 parts of colloidal silica (manufactured by Nippon Aerosil Co., Ltd., R972) was added and mixed using a Henschel mixer to obtain a yellow toner.

  Further, with respect to a ferrite carrier (manufactured by Powdertech) having a volume average particle diameter of 50 μm coated with 1% polymethyl methacrylate, color toner A having a toner concentration of 8% is weighed in a glass bottle and placed on a ball mill table. A yellow developer was obtained by mixing for 5 minutes.

[Toner Production Examples 2 to 4]
Among the formulations of Toner Production Example 1, as a colorant in the colorant dispersion A, Mitsubishi Carbon Black MA-100 (manufactured by Mitsubishi Chemical Corporation) for black toner and P.I. for magenta toner. R. 122 (KET RED309: manufactured by Dainippon Ink & Chemicals, Inc.) B. 15-3 (KET BLUE104: manufactured by Dainippon Ink Chemical Co., Ltd.) was used in the same manner to produce black developer: toner production example 2, magenta developer: toner production example 3, cyan developer: toner production example 4. did.

[Toner Production Example 5]
In the formulation of Toner Production Example 1, a yellow developer was obtained in the same manner except that the charge control agent fine particle dispersion A was replaced with the charge control agent fine particle dispersion B.

[Toner Production Example 6]
In the formulation of Toner Production Example 1, a yellow developer was obtained in the same manner except that the resin dispersion A was replaced with the resin dispersion B.

[Toner Production Example 7]
In the formulation of Toner Production Example 6, a yellow developer was obtained in the same manner except that the charge control agent fine particle dispersion A was replaced with the charge control agent fine particle dispersion B.

[Toner Production Example 8]
A yellow developer was obtained in the same manner as in the toner production example 1 except that the resin dispersion A was replaced with the resin dispersion C.

[Toner Production Example 9]
A yellow developer was obtained in the same manner as in the toner production example 5 except that the resin dispersion A was replaced with the resin dispersion C.

[Toner Production Example 10]
In the formulation of Toner Production Example 1, a yellow developer was obtained in the same manner except that the resin dispersion B was replaced with the resin dispersion D.

[Toner Production Example 11]
In the formulation of Toner Production Example 5, a yellow developer was obtained in the same manner except that resin dispersion B was replaced with resin dispersion D.

[Toner Production Example 12]
In the formulation of Toner Production Example 1, a yellow developer was obtained in the same manner except that the charge control agent fine particle dispersion A was not added.

[Toner Production Example 13]
A yellow developer was obtained in the same manner as in the toner production example 8 except that the charge control agent fine particle dispersion A was not added.

[Toner Production Example 14]
A yellow developer was obtained in the same manner as in the toner production example 6 except that the charge control agent fine particle dispersion A was not added.

[Toner Production Example 15]
First, a suspension polymerization toner was prepared by the following procedure. To 900 g of ion-exchanged water heated to 60 ° C., 3 parts of tricalcium phosphate was added and stirred at 10,000 rpm using a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.) to prepare an aqueous medium. .

Further, the following formulation was put into a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.), heated to 60 ° C., and then stirred at 9,000 rpm for dissolution and dispersion.
-Styrene 160 parts-n-butyl acrylate 40 parts-P.I. Y. 74 (Fast Yellow SG: Sanyo Dye Company) 16 parts Aluminum salicylate compound 4 parts (Bontron E-88: manufactured by Orient Chemical Co., Ltd.)
-Polyester resin 20 parts (polycondensate of propylene oxide modified bisphenol A and isophthalic acid,
Tg = 65 ° C., Mw = 10000, Mn = 6000)
-Stearyl stearate wax (DSC main peak 60 ° C) 30 parts-Divinylbenzene 0.6 parts-Polymer containing sulfur atom (vinyl monomer and SO ₃ X (X = H, alkali metal) group ( 5 parts of a copolymer having a weight average molecular weight of 20000 consisting of (meth) acrylamide (hereinafter sometimes referred to as sulfonic acid acrylamide): CA2)

  In this, 5 parts of a polymerization initiator 2,2'-azobis (2,4-dimethylvaleronitrile) was dissolved to prepare a polymerizable monomer composition.

  The polymerizable monomer composition was put into the aqueous medium, and granulated by stirring at 8,000 rpm using a TK homomixer at 60 ° C. in a nitrogen atmosphere.

  Then, the temperature was raised to 70 ° C. over 2 hours while stirring by transferring to a propeller type stirring device, and further 4 hours later, the temperature was raised to 80 ° C. at a rate of temperature rise of 40 ° C./Hr and reacted at 80 ° C. for 5 hours. To produce polymer particles. After completion of the polymerization reaction, the slurry containing the particles was cooled, washed with an amount of water 10 times that of the slurry, filtered and dried, and then the particle diameter was adjusted by classification to obtain toner particles B of cyan toner. To 100 parts of the obtained toner particles B, 2.0 parts of colloidal silica (manufactured by Nippon Aerosil Co., Ltd., R972) was added and mixed using a Henschel mixer (manufactured by Mitsui Miike Co., Ltd.) to obtain a yellow toner.

  Further, a ferrite carrier having a volume average particle diameter of 50 μm coated with 1% of polymethyl methacrylate (Powder Tech) and color toner A having a toner concentration of 8% with respect to the ferrite carrier are weighed in a glass bottle and ball mill A yellow developer was obtained by mixing for 5 minutes on the table.

[Toner Production Example 16]
A yellow developer was obtained in the same manner as in the toner production example 15 except that the polymer containing sulfur atoms was not added.

[Image evaluation]
The image forming apparatus for performing image evaluation is not particularly limited, and a copying machine as shown in FIG. 2 was used. Specifically, for evaluation of the two-component developer, a commercially available digital copying machine IRC3200 (manufactured by Canon Inc.) was used. In the copying machine, the developer supply system is stopped and only the developing unit can be used. The exposure unit was replaced with a printer capable of printing with no borders, and the fixing speed was set to 190 mm / s, and the copying machine was modified to output 40 sheets / min. Also, the fixing device was changed to a roller whose surface layer was covered with PFA for both the heating roller and the pressure roller, and the length in the direction perpendicular to the rotation direction was extended by 20 mm so as to correspond to the entire solid image. In addition, the width of the transfer device was expanded by 20 mm.

  Using the color toners of Toner Production Examples 1 to 16 as shown in Table 1, Examples 1 to 11 and Comparative Examples 1 and 2 as shown in Table 2 were combined, and plain paper (LETTER size 75 g paper manufactured by XEROX) Further, image evaluation was performed on yellow toner on gloss paper (manufactured by Hewlett-Packard, HP SOFT GLOSS PAPER LETTER 120 g). The evaluation image used was an image in which yellow, yellow and cyan secondary colors, yellow and magenta secondary colors, and 4 black 2 cm square patches, 5 point characters, and line images were repeated. The toner combinations used in the examples are shown in Table 2. The evaluation results are shown in Table 3.

[Fixing roller winding property test]
Fixing wrapping was confirmed at an early stage in a durability test under N / N (23 ° C., 50% RH) and H / H (30 ° C., 80% RH) environment. A solid image having an image paste amount of 1.1 mg / cm ² is placed on a plain paper and a glossy paper that have been completely humidity-controlled, at a position 1 mm from the leading edge of the transfer paper, and an unfixed image is obtained. This was fixed using a fixing machine of IRC3200. 20 sheets of plain paper and glossy paper were passed, and it was confirmed whether or not the fixing member was wound.
A: No winding occurs and a good image is obtained.
B: Wrapping does not occur, but the recording material is wrinkled.
C: Winding occurs.

[Toner scattering evaluation]
In a N / N (23 ° C., 50% RH) environment, it was confirmed that the unfixed image was not scattered on the image with the fixing member removed, and then a solid image with no border on the plain paper. Is printed, and it is confirmed whether or not scattering occurs on the 100-sheet image.
A: Uniform and good without scattering on solid images.
B: Slight scattering is recognized by the loupe check, but it is a solid image that does not cause any problems in the visual check.
C: Although scattering is confirmed visually at the front and rear edges of the solid image, it is not a level that causes a problem in actual use.
D: Level that causes a problem of partial scattering of the solid image at the front and rear ends.
E: It cannot endure actual use visually.

[Image density is thin]
For plain paper, in a N / N (23 ° C., 50% RH) environment, 100 full-border images are printed to check whether the image density is partially reduced. The image density was measured with a Macbeth densitometer 914D (manufactured by Macbeth Co., Ltd.) at the time of 100 sheets, and the difference between the light and dark portions was compared.
A: Difference in image density is less than 0.1.
B: Image density shading difference is 0.1 or more and less than 0.2.
C: Image density shading difference is 0.2 or more and less than 0.3.
D: Image density shading difference is 0.3 or more.

[Blank characters]
After endurance test under L / L (15 ° C, 10% RH), N / N (23 ° C, 50% RH), H / H (30 ° C, 80% RH) environment, 5 point letters and lines Images were made visually and with a magnifying glass. The evaluation criteria are as follows.
A: There is no scattering and the line image and the character image are clear.
B: Slight scattering is recognized by the loupe check, but there is no problem in the visual check.
C: Although a part scattered in the line image and the character image is visually confirmed, it is not a level that causes a problem in actual use.
D: Level at which the part scattered in the line image and the character image is problematic.
E: Unbearable for actual use.

1 is a schematic configuration diagram of a fixing device. 1 is a schematic configuration diagram of an image forming apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Developer hopper container 2 Supply roller 3 Regulating blade 4 Developing roller 5 Photoconductor 6 Developing bias power supply 7 Developer 8 Stir blade 9 Charging roller 10 Exposure device 11 Cleaning device 12 Transfer roller 13 Transfer bias power source 14 Heating roller 15 Pressure roller 16 Conveying belt 17 Transfer roller 18 Backup roller 19 Heating device 20 Intermediate transfer belt 21 Elastic layer 22 Surface layer 23 Roll core 24 Electromagnetic induction coil P Recording material

Claims (4)

A charging process in which a voltage is applied to the charging member to charge the image carrier, an electrostatic latent image forming process in which an electrostatic latent image is formed on the charged image carrier, and toner is transferred to the electrostatic latent image. A developing process for developing the toner image, a transfer process in which the toner image visualized on the image carrier by the toner is electrostatically transferred to the recording material with or without the intermediate transfer member, and on the recording material. In an image forming method having a fixing step of heat-fixing a toner image and repeatedly forming an image on an image carrier,
In the image forming method, an image having at least one of the main scanning direction and the sub-scanning direction longer than the length of the recording material is formed on the image carrier, and a part of the image is transferred to the recording material and fixed. ,
The toner includes an aggregating step of forming an aggregated particle dispersion in a dispersion in which at least a binder resin, resin fine particles including a release agent, and a colorant particle are dispersed to prepare an aggregated particle dispersion; and the aggregated particle dispersion An image forming method, which is a color toner obtained by a wet manufacturing method including a fusing step of fusing the aggregated particles by heating.   The image forming method according to claim 1, wherein the color toner contains a polar resin having a sulfur atom. 3. The image forming method according to claim 1, wherein the color toner is obtained by adding a compound represented by the following structural formula as a charge control agent during the aggregation process. 4.

(In the formula, each of rings A and R represents an aromatic ring residue which may have a substituent, and —OH and —CONH—R are adjacent to each other on the aromatic ring residue A. Combined.)

(In the formula, A ¹ , A ² , R ¹ and R ² each represent an aromatic ring residue which may have a substituent, and B represents a divalent organic group. -OH and -CONH-R ¹ and -OH and -CONH-R ² is attached to the Aitonaru substitution positions on the aromatic ring residue a ^1, a ^2.)   4. The image forming method according to claim 1, wherein the binder resin in the color toner has a peak molecular weight in the range of 5000 to 30000.

Images