JP2007133113A - Image forming method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming method by which stable image density is obtained even under environmental variation and good resolution is also ensured, and the occurrence of banding adversely influential on an image caused by a contact portion of a toner supply roller and a toner carrier after being allowed to stand over a long period of time is suppressed. <P>SOLUTION: A surface of the toner carrier has a contact angle to ethylene glycol of 60-90° and a contact angle to diiodomethane of 30-38°. The toner is a toner for nonmagnetic one-component contact development having toner particles containing at least a binder resin and a colorant, the toner has an average circularity of 0.940-0.995 and a charge amount per unit mass Q/M of -75 to -25 mC/kg, and in toner which is not over 10% number average particle diameter (D(10)), toner whose Q/M is -120 to 0 mC/kg occupies ≥80% by number. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an image forming method for revealing an electrostatic charge latent image.

  2. Description of the Related Art As an electrophotographic apparatus such as a copying machine, a printer, and a facsimile receiving apparatus, an electrophotographic apparatus employing a pressure development method is known. The pressure development method uses a non-magnetic one-component toner as a toner and attaches the toner to the latent image on the photosensitive drum to visualize the latent image, which does not require a magnetic material and is easy to simplify and miniaturize. In addition to the above, it is frequently used because it is easy to colorize the toner.

  The toner carrier used in this electrophotographic development method can sufficiently withstand the heat generated when energized for a long time at a high voltage. In particular, the photoconductor is not contaminated by the decomposition of the polymer member, and the electrical resistance of the member changes. It is necessary not to do (Patent Document 1). Furthermore, since there is a drawback that the fluctuation range of the electric resistance increases due to changes in the environment such as temperature and humidity, there has been a problem that the image density changes greatly due to environmental changes (Patent Document 2). More severely, when a toner supply roller for applying toner to the surface of the toner carrier is provided, the toner supply roller and the toner carrier are in contact with each other, but the electrophotographic apparatus is not operated for a long period of time. When these are kept in contact at the same position for a long period of time, the exuding component from the toner supply roller adheres to the surface of the toner carrier, and as a result, banding occurs in a halftone image or the like. May occur. In particular, this phenomenon can remarkably occur when left in a high temperature and high humidity (40 ° C./95% RH) environment for a long period of time.

  On the other hand, approach from the toner is also performed with respect to the above problem.

  Various improvements have been made on the toner in order to improve development characteristics in electrophotography. In order to obtain good development characteristics, it is important that the toner charge amount distribution is sharp, and that a stable charge amount can be obtained even with environmental fluctuations. In order to deal with such problems, there is a technique in which the toner is a mixture of a toner having a large particle diameter and a toner having a small particle diameter, and the charge amount per unit mass is defined (for example, Patent Document 3). In this document, the use of this technique makes it possible to sharpen the charge amount of the toner and improve the resolution of the image.

  Similarly, there is a technique characterized in that the toner comprises a large particle size toner and a small particle size toner, and the electric resistance of the small particle size toner is lower than the electric resistance of the large particle size toner (for example, Patent Document 4). According to this document, an image with good image density and resolution can be obtained through durability by using this technology.

  However, no mention is made of the ability of any technology with environmental changes, and these current technologies are not sufficient as we are diligently examining them, and there is still room for improvement. It has become clear that it has.

Japanese Patent No. 3186541 Japanese Patent Laid-Open No. 7-13415 Japanese Patent Laid-Open No. 7-248638 JP 11-327192 A

  The problem to be solved by the present invention is to provide an image forming method that solves the problems of the background art. That is, it is to provide an image forming method capable of obtaining a stable image density even with environmental fluctuations and having good resolution. Another object of the present invention is to provide an image forming method that suppresses the adverse effect of banding images caused by a long-term leaving contact portion between a toner supply roller and a toner carrier.

As a result of intensive investigations by the present inventors, the toner carrier and at least a toner supply roller are brought into contact with the surface of the electrostatic latent image carrier directly or via toner, and the toner carrier carries the toner carrier. An image forming method for developing an electrostatic latent image on a surface of an electrostatic latent image carrier with toner to
The toner carrier surface has a contact angle with ethylene glycol of 60 to 90 degrees and a contact angle with diiodomethane of 30 to 38 degrees,
The toner is a non-magnetic one-component contact developing toner having toner particles containing at least a binder resin and a colorant, and the toner has an average circularity of 0.940 or more and 0.995 or less. 80% of toners having a / M of −75 mC / kg to −25 mC / kg and a toner having a Q / M of −120 mC / kg to 0 mC / kg in a toner having a 10% number average diameter (D (10)) or less. Even if the above (however, Q / M: charge amount per unit mass of toner) is accompanied by environmental fluctuations, a stable image density can be obtained, and it is effective for providing an image forming method with good resolution. The present invention was found out.

  According to the present invention, a stable image density can be obtained even with environmental fluctuations, and an image forming method with good resolution can be obtained. In addition, it is possible to obtain an image forming method in which the adverse effect of banding images due to the long-term leaving contact portion between the toner supply roller and the toner carrier is suppressed.

  Hereinafter, the present invention will be described in detail.

  Stabilizing the development characteristics of electrophotography even with environmental fluctuations is not affected by fluctuations in temperature and humidity, and there are many merits, since options such as locations of use are expanded. Therefore, the present inventors diligently studied to improve environmental stability. As a result, a toner having a specific charge amount in a certain circularity range and defining a charge amount on the small particle size side in the particle size distribution is used, and the toner is used with a specific contact angle with respect to a certain substance. It has been found that the environmental stability is improved when used in combination with a toner carrier having the above.

Specifically, it has at least a toner carrier and a toner supply roller, and the surface of the electrostatic latent image carrier is brought into contact with the toner carrier directly or via toner, and the electrostatic latent image is formed by the toner carried by the toner carrier. An image forming method for developing an electrostatic latent image on a surface of a carrier,
The toner carrier surface has a contact angle with ethylene glycol of 60 to 90 degrees and a contact angle with diiodomethane of 30 to 38 degrees, and the toner has toner particles containing at least a binder resin and a colorant. A toner for magnetic one-component contact development, wherein the toner has an average circularity of 0.940 or more and 0.995 or less, the Q / M of the toner is −75 mC / kg to −25 mC / kg, and 10% Toner having a Q / M of −120 mC / kg to 0 mC / kg in the toner having a number average diameter (D (10)) or less is 80% by number or more (where Q / M is the charge amount per unit mass of the toner) ) Is required. It has been found that the development characteristics can be stabilized even with an environmental change only in an image forming method that satisfies this condition.

  Here, when the contact angle with respect to ethylene glycol is 60 to 90 degrees and the contact angle with respect to diiodomethane is not 30 to 38 degrees in the toner carrier, image adverse effects cannot be suppressed. In particular, it is not possible to suppress the adverse effect of banding images due to the long-term leaving contact portion between the toner supply roller and the toner carrier when left for a long time in a high temperature and high humidity environment. Further, even when the contact angle of the toner carrier with ethylene glycol and diiodomethane is within the above range, if the toner to be used is not the circularity, charge amount, or charge amount distribution on the small particle diameter side as described above, the environmental variation is similarly caused. The development characteristics are not satisfied. In addition, the banding image level is also deteriorated.

  Although the reason for this is not clear, the present inventors have found that the exudate and toner from the surface of the toner carrier and the toner supply roller, the respective van der Waals force and the hydrogen bonding force are involved in the harmful effect of this image. I believe. Further, it was considered that the surface chemical characteristics of the toner carrier and the toner shape, the charge amount per unit mass of the toner, the charge amount on the small particle diameter side, and the like are closely related. Therefore, by adopting the above-described image forming method of the present invention, the matching between the toner and the toner carrier is promoted, and the image characteristics such as density, fog, resolution, and banding are excellent and stable even with environmental fluctuations. I think I was able to.

  Here, when the toner Q / M exceeds −25 mC / kg, the charge amount of the toner becomes insufficient and the density is lowered and fogging occurs. However, the environmental fluctuation particularly from a low humidity environment to a high humidity environment. It occurs remarkably when this occurs. Further, when it is less than -75 mC / kg, not only the fog and ghost are deteriorated under a low temperature and low humidity, but also an image with poor resolution when an environmental change from a high humidity environment to a low humidity environment occurs. It becomes. Further, when the toner having a Q / M of −120 mC / kg to 0 mC / kg is less than 80% by number in a toner having a 10% number average diameter (D (10)) or less, the toner is charged in a low temperature and low humidity environment. Not only does the quantity distribution become broad and image ill effects such as ghosting occur, but the charge amount becomes unstable, especially when the humidity environment changes, resulting in image density fluctuations, fogging, or inferior resolution. . When the average circularity of the toner is less than 0.940, the toner charge amount becomes unstable.

  The toner Q / M and the toner% having a Q / M of −120 mC / kg to 0 mC / kg in a toner having a 10% number average diameter (D (10)) or less are the charge amount measurement of the toner described later. The value is measured using a charge amount measuring device “E-SPART ANALYZER MODEL EST-II” (manufactured by Hosokawa Micron).

[Toner carrier]
As shown in FIG. 1, the toner carrier used in the image forming apparatus of the present invention can be configured to have a conductive elastic layer 2 on the outer periphery of a highly conductive shaft 1, as shown in FIG. The surface of the conductive elastic layer 2 has a contact angle with respect to ethylene glycol of 60 to 90 degrees and a contact angle with respect to diiodomethane of 30 to 38 degrees. At this time, the conductive elastic layer 2 may be a single layer or multiple layers, but at least the surface of the conductive elastic layer serving as the surface layer has a contact angle with ethylene glycol of 60 to 90 degrees and a contact angle with diiodomethane. Needs to be 30 to 38 degrees.

  In addition, the toner carrier used in the image forming apparatus of the present invention may have a configuration in which a conductive resin layer 3 is further provided on the conductive elastic layer 2 as shown in FIG. The surface of the conductive resin layer has a contact angle with respect to ethylene glycol of 60 to 90 degrees and a contact angle with diiodomethane of 30 to 38 degrees. The toner carrier having this configuration is preferable because the effects of the present invention can be optimally promoted. Each of the conductive elastic layer 2 and the conductive resin layer 3 may be a single layer or multiple layers, but at least the surface of the conductive resin layer serving as the surface layer has a contact angle with respect to ethylene glycol of 60 to 90 degrees, and The contact angle with respect to diiodomethane needs to be 30 to 38 degrees.

  Any material can be used as the highly conductive shaft 1 as long as it has good conductivity. Usually, it is a metal cylinder having an outer diameter of 4 to 10 mm formed of aluminum, iron, SUS, or the like. Is used.

The conductive elastic layer 2 formed on the outer periphery of the good conductive shaft 1 uses an elastomer such as EPDM or urethane, or other resin molding as a base material, and an electron such as carbon black, metal, or metal oxide. A material prepared by blending a conductive substance or an ionic conductive substance such as sodium perchlorate and adjusting the appropriate resistance region (volume resistivity) to 10 ³ to 10 ¹⁰ Ωcm, preferably 10 ⁴ to 10 ⁸ Ωcm. Form. The hardness of the conductive elastic layer is preferably 25-60 degrees in terms of ASKER-C hardness. The conductive elastic layer can be used in a thickness of 0.3 mm to 10 mm, preferably in the range of 1.0 mm to 5.0 mm.

  Specific examples of the base material include polyurethane, natural rubber, butyl rubber, nitrile rubber, polyisoprene rubber, polybutadiene rubber, silicone rubber, styrene-butadiene rubber, ethylene-propylene rubber, ethylene-propylene-diene rubber, chloroprene rubber, Acrylic rubber, and a mixture thereof may be mentioned, and silicone rubber or EPDM (ethylene-propylene-diene rubber) is preferably used.

  Examples of the electronic conductive material used for imparting conductivity to the conductive elastic layer 2 include conductive carbon such as ketjen black EC and acetylene black, SAF, ISAF, HAF, FEF, GPF, SRF, FT, Examples include carbon for rubber such as MT, carbon for color (ink) subjected to oxidation treatment, metal such as copper, silver, germanium, and metal oxide. Among these, carbon black (conductive carbon, carbon for rubber, carbon for color (ink), etc.) is preferable because the conductivity can be easily controlled with a small amount. These conductive powders are usually suitably used in the range of 0.5 to 50 parts by mass, particularly 1 to 30 parts by mass with respect to 100 parts by mass of the base material.

  Examples of the ion conductive material used to impart conductivity to the conductive elastic layer 2 include inorganic ion conductive materials such as sodium perchlorate, lithium perchlorate, calcium perchlorate, and lithium chloride. Examples thereof include modified aliphatic dimethyl ammonium etosulphate and stearyl ammonium acetate organic ion conductive materials.

  As for the conductivity-imparting agents such as these electron conductive materials and ion conductive materials, the amount necessary to make the conductive elastic layer have an appropriate volume resistivity as described above is used. 0.5 to 50 parts by mass, preferably 1 to 30 parts by mass with respect to parts.

  As the base material of the conductive resin layer 3 covering the conductive elastic layer 2 of the conductive roller having the configuration shown in FIG. 2, polyamide resin, urethane resin, urea resin, imide resin, melamine resin, fluororesin, phenol Examples thereof include resins, alkyd resins, silicone resins, polyester resins, polyether resins, and the like, and mixtures thereof. Urethane resin is preferably used as a base material for the conductive resin layer 3 because it has a large ability to charge toner by friction and has wear resistance.

  At this time, the urethane resin is composed of an isocyanate component and a polyol component. As the polyol component, polyether polyol, polyester polyol, polycaprolactone polyol, polycarbonate polyol, polyolefin polyol, polymer polyol and the like are used. As the polyol that effectively promotes the present invention, a polyether polyol is preferable. Specifically, the following formula (1)

（式中ｌは正の整数を示す。）
で示されるユニット（ＢＯ）、下記式（２）

(In the formula, l represents a positive integer.)
A unit (BO) represented by the following formula (2)

（式中ｍは正の整数を示す。）
で示されるユニット（ＰＯ）、及び、下記式（３）

(In the formula, m represents a positive integer.)
The unit (PO) represented by the following formula (3)

（式中ｎは正の整数を示す。）
で示されるユニットが、用いられるポリエーテルポリオールに含まれることが好ましい。このとき、式（１）、式（２）、式（３）で示されるユニットが全て１分子中に含まれるポリエーテルポリオール、または式（１）、式（２）、式（３）で示されるユニットが１分子中に少なくとも一種類以上含まれるポリエーテルポリオールのうちいずれでも用いることができるが、ウレタンの原材料として用いるポリエーテルポリオールは必ず式（１）、式（２）、式（３）で示されるユニットを全て含むようになるように調整することが良い。これは、式（１）、式（２）、式（３）で示されるユニットはそれぞれ炭素数に対するエーテル基の数が異なり、これらを併用することにより、現像剤に対する帯電付与性やファンデルワールス力などを緻密にコントロールすることができるからである。

(In the formula, n represents a positive integer.)
It is preferable that the unit shown by is contained in the polyether polyol used. At this time, the polyether polyol in which all the units represented by the formula (1), the formula (2) and the formula (3) are contained in one molecule, or the formula (1), the formula (2) and the formula (3) Any of the polyether polyols in which at least one unit is contained in one molecule can be used, but the polyether polyol used as a raw material for urethane is always represented by formula (1), formula (2), formula (3). It is good to adjust so that all the units shown by may be included. This is because the units represented by formula (1), formula (2), and formula (3) differ in the number of ether groups relative to the number of carbon atoms, and by using these together, the charge imparting property to the developer and van der Waals This is because power and the like can be precisely controlled.

  At this time, the polyether polyol (BO) having a unit represented by the formula (1) has a type having two or more hydroxyl groups, and the polyether polyol (PO) having a unit represented by the formula (2) has a hydroxyl group. As the polyether polyol (EO) having a type having one unit and the polyether polyol (EO) having a unit represented by the formula (3), those having a type having one hydroxyl group are preferably used because the effects of the present invention are promoted. Furthermore, it is more preferable that the polyether polyol (PO-EO) having the unit represented by the formula (2) and the unit represented by the formula (3) simultaneously has one hydroxyl group.

  As a result of further detailed investigation, the present invention can be adjusted so that the mass ratio of BO, PO, and EO of the polyether polyol used is BO: PO: EO = 100: 3: 2 to 100: 25: 20. This is preferable because it promotes the effect.

  Moreover, it is also preferable to adjust so that the mass ratio of BO: (PO-EO) of the polyether polyol to be used may be BO: (PO-EO) = 100: 5 to 100: 40.

  Specific examples of the isocyanate component of the urethane resin include tolylene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), naphthalene diisocyanate (NDI), tolidine diisocyanate (TODI), hexamethylene diisocyanate (HDI), isophorone diisocyanate (IPDI), Examples thereof include phenylene diisocyanate (PPDI), xylene diisocyanate (XDI), tetramethylxylene diisocyanate (TMXDI), and cyclohexane diisocyanate. Among these, aromatic isocyanate compounds such as tolylene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), naphthalene diisocyanate (NDI), phenylene diisocyanate (PPDI), xylene diisocyanate (XDI), tetramethylxylene diisocyanate (TMXDI) In particular, diphenylmethane diisocyanate (MDI) is preferable because it can improve the resilience of the developing roller after a local load.

  This isocyanate component is adjusted so that mass ratio with respect to all the polyols to be used becomes isocyanate: polyol = 20: 80-60: 40.

In the conductive resin layer 3, a conductivity-imparting agent such as an electronic conductive material or an ionic conductive material is blended with the base material, and an appropriate resistance region (volume resistivity) is 10 ³ to 10 ¹¹ Ωcm, preferably Is formed of a material adjusted to 10 ⁴ to 10 ¹⁰ Ωcm. Moreover, although the thickness of the conductive resin layer can be used in the range of 0.5 μm to 200 μm, it can be preferably used in the range of 1.0 μm to 100 μm.

  The thickness of the conductive elastic layer or conductive resin layer of the present invention was determined by cutting a roller on which the conductive elastic layer and the conductive surface layer were formed, measuring the cross-section at nine points, and calculating the average value. When the thickness was thin like the conductive resin layer, the cross section was measured at 9 points with a video microscope (magnification 1000 to 3000 times) and the average value was obtained.

  The kneading of the resin serving as the base material and the conductivity-imparting agent such as the electronic conductive material or the ionic conductive material is performed using a ball mill or the like to form the toner carrier surface roughness as occasion demands. After the coarse particles are added and dispersed, it can be carried out by adding a curing agent or a curing catalyst or the like at an appropriate time and stirring. The obtained composition is applied by a method such as spraying or dipping. Alternatively, a conductive elastic layer or a conductive resin layer is integrally formed by injecting the obtained composition into a cavity of a molding die in which a core metal is pre-arranged, and heating to cause reaction hardening or solidification. A method of cutting into a predetermined shape and dimensions such as a tube shape by cutting or the like from a slab or block separately formed using the above composition in advance, and press-fitting a core metal into this to conduct electricity on the core metal Examples thereof include a method of manufacturing by coating an elastic layer or a conductive resin layer, a method of appropriately combining these methods, and the like. If desired, the outer diameter may be further adjusted to a predetermined outer diameter by cutting or polishing treatment.

  Examples of the roughening particles include rubber particles such as EPDM, NBR, SBR, CR, and silicone rubber, or elastomer particles such as polystyrene, polyolefin, polyvinyl chloride, polyurethane, polyester, and polyamide-based thermoplastic elastomer (TPE). Or resin particles such as PMMA particles, urethane resin particles, fluorine resin, silicone resin, phenol resin, naphthalene resin, furan resin, xylene resin, divinylbenzene polymer, styrene-divinylbenzene copolymer, polyacrylonitrile resin alone or They can be used in combination. At this time, the surface roughness Rz of the toner carrier is generally adjusted to 1 to 15 μm. At this time, the surface roughness of the roller is set to Rz according to JIS B0601: 2001.

〔toner〕
The toner used in the image forming method of the present invention preferably has a sharp particle size distribution. Specifically, the volume average particle diameter (D4) / number average particle diameter (D1) of the toner is preferably in the range of 1.05 to 1.30. By having a particle size distribution in the numerical range, it is easy to obtain a toner with a sharper charge amount distribution. Here, when the volume average particle diameter (D4) / number average particle diameter (D1) is less than 1.05, the toner fluidity tends to be inferior, and the charge amount may be insufficient, and the volume average particle diameter (D4). / When the number average particle diameter (D1) exceeds 1.30, the charge amount distribution tends to be broad.

  The toner used in the image forming method of the present invention is 85 toners having a Q / M of −120 mC / kg to 0 mC / kg in a toner having a 10% number average diameter (D (10)) or less. % Or more is preferable. When the toner having a Q / M of −120 mC / kg to 0 mC / kg is less than 85% by number in the toner having a 10% number average diameter (D (10)) or less, the toner is used in a low temperature and low humidity environment. In addition to the potential for image damage such as ghosting, the charge amount may become unstable, especially when the humidity environment changes. Fluctuations, fogging, or images with poor resolution tend to occur. Furthermore, toner having a Q / M of −120 mC / kg to 0 mC / kg in a toner having a 10% number average diameter (D (10)) or less of the toner is set to 90 number% or more. Can be brought into the most desirable state.

  The toner used in the image forming method of the present invention preferably contains a polymer or copolymer of a sulfonic acid group, a sulfonic acid group or a sulfonic acid ester group. A polymer or copolymer of a sulfonic acid group, a sulfonic acid group, or a sulfonic acid ester group has a high polarity, and by adding the polymer or copolymer to the toner, the charge amount of the toner may vary with the environment. It tends to be stable.

Furthermore, the toner used in the image forming method of the present invention preferably contains an aromatic oxycarboxylic acid metal compound (Al, Zn, Cr, Co, Ni, Zr, Ti, Cu, Fe). By containing the substance in the toner, the concentration and fogging in a high temperature and high humidity environment tend to be good. When the toner is divided into two by a classifier, a toner (F) having a smaller number average particle diameter (D1) than the toner and a toner (G) having a larger number average particle diameter (D1) than the toner. The following formula (4) is preferably satisfied when the masses of the oxycarboxylic acids of toners (F) and (G) are Bf and Bg, respectively.
0 <Bf / Bg <2.5 (4)

  In the case of 1.0 ≧ Bf / Bg, the charge amount of the toner may become lower, and the density tends to decrease particularly when the environment changes from a low humidity environment to a high humidity environment. . When Bf / Bg ≧ 2.5, the charge amount of the toner may be increased, and when the environment changes from a high humidity environment to a low humidity environment, dot reproduction is performed on the image. The image quality may deteriorate and the resolution may be inferior. Moreover, such a tendency can be further suppressed by setting Bf / Bg <2.0.

  In the present invention, as a method for dividing the toner into toner (F) and toner (G), an air classification (using an elbow jet classification device EJ-L-3 (manufactured by Nippon Steel & Mining)) is used. Do. The toner (F) and toner (G) are the toners obtained by classifying the original toner once.

  Hereinafter, the toner used in the present invention will be described in more detail. The method for producing the toner according to the present invention is not particularly limited in the pulverization method or the polymerization method, but the volume average particle diameter (D4) / number average particle diameter (D1), which is a preferable requirement of the toner according to the present invention, is 1. In order to sharpen the particle size distribution of the toner from 0.05 to 1.30, it is preferable to produce the toner by a polymerization method.

  Examples of the toner production method by polymerization include a direct polymerization method, a suspension polymerization method, an emulsion polymerization method, an emulsion association polymerization method, and a seed polymerization method. Among these, the balance between the particle size and the particle shape is balanced. In view of easiness, it is particularly preferable to produce by suspension polymerization. In this suspension polymerization method, a monomer composition is prepared by uniformly dissolving or dispersing a colorant (and, if necessary, a polymerization initiator, a crosslinking agent, a charge control agent, and other additives) in the polymerizable monomer. Then, the monomer composition is dispersed in a continuous layer (for example, an aqueous phase) containing a dispersion stabilizer by using an appropriate stirrer, and a polymerization reaction is performed to have a desired particle size. Toner is obtained. When the toner is produced by this suspension polymerization method, since the individual toner particle shapes are substantially spherical, the charge amount distribution is relatively uniform and a toner having satisfactory development characteristics can be easily obtained.

  Examples of the polymerization initiator used in the present invention include tert-butyl peroxyacetate, tert-butyl peroxylaurate, tert-butyl peroxypivalate, tert-butyl peroxy-2-ethylhexanoate, tert-butylperoxyisobutyrate, tert-butylperoxyneodecanoate, tert-hexylperoxyacetate, tert-hexylperoxylaurate, tert-hexylperoxypivalate, tert-hexylperoxy-2- Ethyl hexanoate, tert-hexylperoxyisobutyrate, tert-hexylperoxyneodecanoate, tert-butylperoxybenzoate, α, α'-bis (neodecanoylperoxy) diisopropylbenze , Cumyl peroxyneodecanoate, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate, 1,1,3,3-tetramethylbutylperoxyneodecanoate, 1 -Cyclohexyl-1-methylethylperoxyneodecanoate, 2,5-dimethyl-2,5-bis (2-ethylhexanoylperoxy) hexane, 1-cyclohexyl-1-methylethylperoxy-2-ethyl Hexanoate, tert-hexyl peroxyisopropyl monocarbonate, tert-butyl peroxyisopropyl monocarbonate, tert-butyl peroxy 2-ethylhexyl monocarbonate, tert-hexyl peroxybenzoate, 2,5-dimethyl-2,5- Bis (benzoylperoxy) hexane tert-butylperoxy-m-toluoylbenzoate, bis (tert-butylperoxy) isophthalate, tert-butylperoxymaleic acid, tert-butylperoxy-3,5,5-trimethylhexanoate, 2 , 5-dimethyl-2,5-bis (m-toluoylperoxy) hexane, tert-amyl peroxyneodecanoate, tert-amyl peroxypivalate, tert-amyl peroxy 2-ethylhexanoate, Peroxyesters such as tert-amyl peroxynormal octoate, tert-amyl peroxyacetate, tert-amyl peroxyisononanoate, tert-amyl peroxybenzoate, benzoyl peroxide, lauroyl peroxide , Diacyl peroxide such as isobutyryl peroxide, succinic peroxide, diisopropyl peroxydicarbonate, di-2-ethoxyethyl peroxydicarbonate, di-2-ethylhexyl peroxydicarbonate, di-sec-butylperoxy Organic peroxides such as peroxydicarbonates such as dicarbonate, 2,2′-azobis- (2,4-dimethylvaleronitrile), 2,2′-azobisisobutyronitrile, 1,1 ′ -Azo-based polymerization initiation such as azobis (cyclohexane-1-carbonitrile), 2,2'-azobis-4-methoxy-2,4-dimethylvaleronitrile, azobisisobutyronitrile, etc. is used alone or in combination. It is possible.

  In the production of the polymerized toner of the present invention, examples of the polymerizable monomer constituting the polymerizable monomer composition include the following.

  Examples of the polymerizable monomer include styrene monomers such as styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, p-methoxystyrene, p-ethylstyrene, methyl acrylate, ethyl acrylate, Acrylate esters such as n-butyl acrylate, isobutyl acrylate, n-propyl acrylate, n-octyl acrylate, dodecyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, 2-chloroethyl acrylate, and phenyl acrylate , Methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, phenyl methacrylate, Methacrylic acid dimethyl aminoethyl, methacrylic acid esters other acrylonitrile such as diethylaminoethyl methacrylate, methacrylonitrile, and the like monomers acrylamide. These monomers can be used as a mixture.

  As the colorant used in the invention, carbon black, a magnetic material, and a yellow / magenta / cyan colorant shown below are used as the black colorant, and colors adjusted to each color are used. Moreover, it is necessary to pay attention to the polymerization inhibitory property and water phase transferability of the colorant. The colorant is preferably subjected to surface modification (for example, a hydrophobic treatment without polymerization inhibition). In particular, since dyes and carbon black have many polymerization-inhibiting properties, care must be taken when using them.

  As the yellow colorant, compounds typified by condensed azo compounds, isoindolinone compounds, anthraquinone compounds, azo metal complexes, methine compounds, and allylamide compounds are used. Specifically, C.I. I. Pigment Yellow 12, 13, 14, 15, 17, 62, 74, 83, 93, 94, 95, 109, 110, 111, 128, 129, 147, 168, 180, etc. are preferably used.

  As the magenta colorant, condensed azo compounds, diketopyrrolopyrrole compounds, anthraquinones, quinacridone compounds, basic dye lake compounds, naphthol compounds, benzimidazolone compounds, thioindigo compounds, and perylene compounds are used. Specifically, C.I. I. Pigment Red 2, 3, 5, 6, 7, 23, 48: 2, 48: 3, 48: 4, 57: 1, 81: 1, 122, 146, 166, 169, 177, 184, 185, 202, 206, 220, 221, 254 are particularly preferred.

  As the cyan colorant used in the present invention, copper phthalocyanine compounds and derivatives thereof, anthraquinone compounds, basic dye lake compounds, and the like can be used. Specifically, C.I. I. Pigment Blue 1, 7, 15, 15: 1, 15: 2, 15: 3, 15: 4, 60, 62, 66 and the like are particularly preferably used.

  These colorants can be used alone or in combination and further in the form of a solid solution. The colorant of the present invention is selected from the viewpoints of hue angle, saturation, brightness, weather resistance, OHP transparency, and dispersibility in the toner. The colorant is added in an amount of 1 to 20 parts by mass with respect to 100 parts by mass of the resin.

  Further, the toner of the present invention can be used as a magnetic toner by containing a magnetic material as a colorant. In this case, the magnetic material can also serve as a colorant. In the present invention, the magnetic material contained in the magnetic toner includes iron oxides such as magnetite, hematite and ferrite; metals such as iron, cobalt and nickel, or aluminum, cobalt, copper, lead, magnesium and tin of these metals. And alloys of metals such as zinc, antimony, beryllium, bismuth, cadmium, calcium, manganese, selenium, titanium, tungsten, vanadium, and mixtures thereof.

  The magnetic material used in the present invention is more preferably a surface-modified magnetic material. When used in a polymerization toner, the magnetic material is subjected to a hydrophobizing treatment with a surface modifier that is a substance that does not inhibit polymerization. Is preferred. Examples of such surface modifiers include silane coupling agents and titanium coupling agents.

  These magnetic materials preferably have an average particle size of 2 μm or less, preferably about 0.1 to 0.5 μm. The amount to be contained in the toner particles is about 20 to 200 parts by mass, particularly preferably 40 to 150 parts by mass with respect to 100 parts by mass of the binder resin.

  The toner used in the image forming method of the present invention may contain a release agent. Usable release agents include petroleum waxes such as paraffin wax, microcrystalline wax, petrolactam and derivatives thereof, montan wax and derivatives thereof, hydrocarbon waxes and derivatives thereof by Fischer-Tropsch method, and polyolefins represented by polyethylene Natural waxes and derivatives thereof such as wax and derivatives thereof, carnauba wax and candelilla wax, and the derivatives include oxides, block copolymers with vinyl monomers, and graft modified products. Furthermore, fatty acids such as higher aliphatic alcohols, stearic acid and palmitic acid, or compounds thereof, acid amide waxes, ester waxes, ketones, hardened castor oil and derivatives thereof, plant waxes, animal waxes, silicone oils, etc. are also used. it can.

  Among these, ester wax and hydrocarbon wax are preferable from the viewpoint of excellent releasability.

  And it is preferable that this mold release agent contains 1-30 mass% with respect to binder resin. More preferably, it is 3 to 25% by mass. When the content of the release agent is less than 1% by mass, the effect of adding the release agent is not sufficient, and further, the offset suppressing effect is also insufficient. On the other hand, if it exceeds 30% by mass, the long-term storage stability is deteriorated and the dispersibility of the toner material such as the colorant is deteriorated, leading to deterioration of the coloring power of the toner and deterioration of image characteristics. In addition, exudation of the release agent is likely to occur, and the durability under high temperature and high humidity is inferior. Further, since a large amount of the release agent is included, the toner shape tends to become distorted.

  In the production of the polymerized toner used in the image forming method of the present invention, polymerization may be performed by adding a resin to the polymerizable monomer composition. For example, it contains hydrophilic functional groups such as amino groups, carboxylic acid groups, hydroxyl groups, sulfonic acid groups, glycidyl groups, and nitrile groups that cannot be used because monomers are water-soluble and dissolve in aqueous suspension to cause emulsion polymerization. When it is desired to introduce the polymerizable monomer component into the toner, a random copolymer of these and a vinyl compound such as styrene or ethylene, a block copolymer, or a graft copolymer, and the like, Alternatively, it can be used in the form of a polycondensate such as polyester or polyamide, or a polyaddition polymer such as polyether or polyimine. When such a polymer containing a polar functional group is allowed to coexist in the toner, the above-described wax component is phase-separated, the encapsulation becomes stronger, and a toner having good blocking resistance and developability can be obtained.

  Among these resins, the effect is greatly increased by containing a polyester resin. I think this is because of the following reasons. Since the polyester resin contains many ester bonds which are functional groups having relatively high polarity, the polarity of the resin itself is increased. Due to its polarity, the tendency of the polyester to be unevenly distributed on the surface of the droplets in the aqueous dispersion medium becomes strong, and the polymerization proceeds while maintaining this state, resulting in a toner. For this reason, when the polyester resin is unevenly distributed on the toner surface, the surface state and the surface composition become uniform. As a result, the chargeability becomes uniform, and a very good developability can be obtained by a synergistic effect with the good inclusion property of the release agent.

  The toner used in the image forming method of the present invention preferably contains a polymer or copolymer of a sulfonic acid group, a sulfonic acid group or a sulfonic acid ester group. Monomers having a sulfonic acid group for producing this polymer are styrene sulfonic acid, 2-acrylamido-2-methylpropane sulfonic acid, 2-methacrylamide-2-methylpropane sulfonic acid, vinyl sulfonic acid, methacrylic acid. Examples include sulfonic acid.

  The polymer containing a sulfonic acid group according to the present invention may be a homopolymer of the above monomer, or may be a copolymer of the above monomer and another monomer. Absent. As a monomer that forms a copolymer with the above monomer, there is a vinyl polymerizable monomer, and 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 butyrate, 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.

  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, 2,2′-bis (4-methacryloxy / polyethoxy) phenyl) propane, trimethylolpropane trimethacrylate, tetramethylolmethane tetramethacrylate, divinylbenzene, divinylnaphthalene, divinyl ether, and the like.

  As the polymer having a sulfonic acid group, the monomers as described above can be used, but it is more preferable that the polymer contains a styrene derivative as a monomer.

  The toner of the present invention may contain a charge control agent in order to stabilize the charge characteristics. As the charge control agent, a known one can be used, and a charge control agent that has a high charging speed and can stably maintain a constant charge amount is particularly preferable. Further, when the toner is produced by a direct polymerization method, a charge control agent having a low polymerization inhibitory property and substantially free from a solubilized product in an aqueous dispersion medium is particularly preferable. Specific compounds include, as negative charge control agents, metal compounds of aromatic carboxylic acids such as salicylic acid, alkylsalicylic acid, dialkylsalicylic acid, naphthoic acid and dicarboxylic acid, metal salts or metal complexes of azo dyes or azo pigments, sulfones Examples thereof include a polymer compound having an acid or carboxylic acid group in the side chain, a boron compound, a urea compound, a silicon compound, and a calixarene. Examples of the positive charge control agent include a quaternary ammonium salt, a polymer compound having the quaternary ammonium salt in the side chain, a guanidine compound, a nigrosine compound, and an imidazole compound.

  As a method of incorporating a charge control agent into the toner, there are a method of adding it inside the toner particles and a method of adding it externally. The amount of these charge control agents used is determined by the toner production method including the type of binder resin, the presence or absence of other additives, and the dispersion method, and is not uniquely limited. When added internally, it is preferably used in the range of 0.1 to 10 parts by mass, more preferably 0.1 to 5 parts by mass with respect to 100 parts by mass of the binder resin. In addition, when externally added, the amount is preferably 0.005 to 1.0 part by mass, more preferably 0.01 to 0.3 part by mass with respect to 100 parts by mass of the toner.

  In the polymerization method for producing the toner of the present invention, generally, the above-described colorant, magnetic powder, release agent and other toner compositions are appropriately added to the polymerizable monomer to produce a homogenizer, ball mill, colloid mill, A polymerizable monomer composition is obtained by uniformly dissolving or dispersing by a dispersing machine such as an ultrasonic dispersing machine. This is suspended in an aqueous medium containing a dispersion stabilizer. At this time, the particle size of the obtained toner particles becomes sharper by using a high-speed disperser such as a high-speed stirrer or an ultrasonic disperser to obtain a desired toner particle size at a stretch. The polymerization initiator may be added at the same time when other additives are added to the polymerizable monomer, or may be mixed immediately before being suspended in the aqueous medium. It can also be added during granulation or immediately after granulation.

  After granulation, stirring may be performed using a normal stirrer to such an extent that the particle state is maintained and particle floating and sedimentation are prevented.

  In the production of the polymerized toner of the present invention, known surfactants, organic dispersants and inorganic dispersants can be used as dispersion stabilizers. In particular, inorganic dispersants are less likely to produce harmful ultrafine powders, and because of their steric hindrance, dispersion stability is obtained, so even if the reaction temperature is changed, stability is not easily lost, and washing is easy and does not adversely affect the toner. Therefore, it can be preferably used. Examples of such inorganic dispersants include polyvalent metal phosphates such as calcium phosphate, magnesium phosphate, aluminum phosphate and zinc phosphate, carbonates such as calcium carbonate and magnesium carbonate, calcium metasuccinate, calcium sulfate and barium sulfate. Inorganic oxides such as inorganic salts, calcium hydroxide, magnesium hydroxide, aluminum hydroxide, silica, bentonite and alumina can be mentioned.

  When these inorganic dispersants are used, they may be used as they are, but in order to obtain finer particles, the inorganic dispersant particles can be generated and used in an aqueous medium. For example, in the case of calcium phosphate, a sodium phosphate aqueous solution and a calcium chloride aqueous solution can be mixed with high-speed stirring to produce water-insoluble calcium phosphate, which enables more uniform and fine dispersion. At the same time, a water-soluble sodium chloride salt is produced as a by-product. However, if a water-soluble salt is present in the aqueous medium, dissolution of the polymerizable monomer in water is suppressed, and an ultrafine toner based on emulsion polymerization is produced. Since it becomes difficult to generate | occur | produce, it is more convenient. The inorganic dispersant can be almost completely removed by dissolving with an acid or alkali after completion of the polymerization.

  These inorganic dispersants are desirably used alone in an amount of 0.2 to 20 parts by mass with respect to 100 parts by mass of the polymerizable monomer. Since it is slightly weak, 0.001-0.1 part by mass of a surfactant may be used in combination.

  Examples of the surfactant include sodium dodecylbenzene sulfate, sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate, sodium oleate, sodium laurate, sodium stearate, potassium stearate and the like.

  After the polymerization is completed, the polymerized toner particles are filtered, washed and dried by a known method, and if necessary, inorganic fine powder is mixed and adhered to the surface, whereby the toner of the present invention can be obtained. Moreover, it is one of the desirable forms of this invention to put a classification process in a manufacturing process and to cut coarse powder and fine powder.

  In the present invention, the toner is preferably added with inorganic fine powder having a number average primary particle size of 4 to 100 nm as a fluidizing agent. The inorganic fine powder is added to improve the fluidity of the toner and to make the charge of the toner particles uniform. However, adjustment of the charge amount of the toner, improvement of environmental stability, etc. by treatment such as hydrophobizing the inorganic fine powder. It is also a preferable form to provide the function.

(Toner supply roller)
The toner supply roller used in the image forming method of the present invention will be described in detail. As the toner supply roller, a toner supply roller having a highly conductive shaft as a core and a foamed elastic layer formed on the outer periphery thereof, and the foamed elastic layer containing a copolymer of silicone and polyether is suitable. Can be used.

  Examples of the material (base material) for the foamed elastic layer include polyurethane, nitrile rubber, ethylene propylene rubber, ethylene propylene diene rubber, styrene butadiene rubber, butadiene rubber, isoprene rubber, natural rubber, silicone rubber, acrylic rubber, chloroprene rubber, From foamed elastic bodies obtained by using rubber raw materials such as butyl rubber and epichlorohydrin rubber, or monomers or the like that are raw materials for producing these rubber raw materials (these monomers may also be referred to as rubber raw materials). Select and use. It may be a foamed elastic body obtained by using the rubber raw material alone or a rubber raw material combining two or more of these rubber raw materials. Among these foamed elastic bodies, polyurethane foam is preferably used.

  As the polyol component constituting the raw material for forming the polyurethane foam, any of known polyols such as polyether polyol, polyester polyol, and polymer polyol, which are generally used in the production of flexible polyurethane foam, can be used. . Moreover, as a polyisocyanate component which comprises the raw material for forming a polyurethane foam, well-known at least bifunctional or more polyisocyanate is used. For example, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, orthotoluidine diisocyanate, naphthylene diisocyanate, xylylene diisocyanate, 4,4'-diphenylmethane diisocyanate, carbodiimide modified MDI, polymethylene polyphenyl isocyanate, polymeric poly Isocyanates and the like are used alone or in combination.

  The polyurethane foam raw material in which these polyol component and polyisocyanate component are blended preferably contains a copolymer of silicone and polyether. Although this component plays a role as a foam stabilizer, there are no particular restrictions on both the silicone part and the polyether part, and it is preferably used with known materials.

  Furthermore, crosslinking agents, foaming agents (water, low-boiling substances, gas bodies, etc.), surfactants, catalysts, conductivity-imparting agents for imparting desired conductivity, antistatic agents, and the like can be added. .

  The manufacturing method of the toner supply roller of the present invention is not particularly limited, and a suitable method may be selected from known manufacturing methods and manufactured. Specifically, it is produced by forming a foamed elastic layer by coating a cored bar made of a metal material such as iron or stainless steel, usually having a diameter of 4 to 10 mm and a length of 200 to 400 mm, with a foamed elastic body. can do. The outer diameter of the toner supply roller is not particularly limited, and may have various outer diameters depending on the purpose. In general, the outer diameter may be 10 to 20 mm.

  For example, after preparing a polyurethane raw material composition by homogeneously mixing a polyurethane raw material, a copolymer of silicone and polyether, a foaming agent, a catalyst used as required, a crosslinking agent, a chain extender, and other auxiliary agents, A method of injecting the raw material composition into a cavity of a molding die in which a metal core is preliminarily disposed, and heating and reaction-curing or solidifying to integrally form a foamed elastic layer, the polyurethane raw material composition in advance A foamed elastic slab or block that is separately formed using an object is cut into a predetermined shape or size such as a tube by cutting or the like, and a cored bar is press-fitted into this to cover the foamed elastic layer on the cored bar And a method of appropriately combining these methods. If desired, the outer diameter may be further adjusted to a predetermined outer diameter by cutting or polishing treatment.

  Next, the image forming method of the present invention will be described with reference to FIGS.

  The configuration of the image forming apparatus including the image forming method of this embodiment is shown in FIG. The image forming apparatus of this example is a laser beam printer using a transfer type electrophotographic process.

  FIG. 4 is a sectional view of a tandem type color LBP (color laser printer) as an example of an image forming apparatus used in the image forming method according to the present invention.

  In FIG. 4, reference numeral 101 (101a to 101d) denotes a drum-type electrophotographic photosensitive member (hereinafter referred to as a photosensitive drum) as a latent image carrier that rotates in a direction indicated by an arrow (counterclockwise) at a predetermined process speed. The photosensitive drums 101a, 101b, 101c, and 101d respectively share the yellow (Y) component, magenta (M) component, cyan (C) component, and black (Bk) component of the color image. These photosensitive drums 101a to 101d are rotationally driven by a drum motor (DC servo motor) (not shown), but independent driving sources may be provided for the respective photosensitive drums 101a to 101d. The rotational drive of the drum motor is controlled by a DSP (digital signal processor) (not shown), and other controls are performed by a CPU (not shown).

  The electrostatic adsorption conveyance belt 109a is stretched around a driving roller 109b, fixed rollers 109c and 109e, and a tension roller 109d. The electrostatic adsorption conveyance belt 109a is rotationally driven by the driving roller 109b in the direction of the arrow in the figure to adsorb and convey the recording medium S. To do.

  Hereinafter, yellow (Y) of the four colors will be described as an example.

  The photosensitive drum 101a is uniformly charged to a predetermined polarity and potential by the primary charging means 102a during its rotation. The photosensitive drum 101a is exposed to a light image by a laser beam exposure means (hereinafter referred to as a scanner) 103a, and an electrostatic latent image of image information is formed on the photosensitive drum 101a.

  Next, a toner image is formed on the photosensitive drum 101a by the developing unit 104a, and the electrostatic latent image is visualized. Similar steps are performed for the other three colors (magenta (B), cyan (C), and black (Bk)).

  Thus, the four-color toner images are synchronized with the photosensitive drums 101a to 101d by the registration rollers 108c that stop and re-transport the recording medium S conveyed by the paper feed roller 108b at a predetermined timing. The toner images are sequentially transferred onto the recording medium S at the nip portion with the belt 109a. At the same time, the photosensitive drums 101a to 101d after the transfer of the toner image to the recording medium S are subjected to repeated image formation by removing residual deposits such as transfer residual toner by the cleaning means 106a, 106b, 106c and 106d. .

  The recording medium S on which the toner images are transferred from the four photosensitive drums 101a to 101d is separated from the surface of the electrostatic attraction / conveyance belt 109a by the driving roller 109b and sent to the fixing device 110, and the toner image is fixed by the fixing device 110. Then, the sheet is discharged to the discharge tray 113 by the discharge roller 110c.

  Next, a specific example of the image forming method in the non-magnetic one-component contact developing method applied as the present invention will be described with reference to an enlarged view of the developing portion (FIG. 3). In FIG. 3, the developing unit 13 is located in a developer container 23 containing a non-magnetic toner 17 as a one-component developer, and an opening extending in the longitudinal direction in the developer container 23. A photosensitive drum) 10 and a toner carrier 14 disposed opposite to each other, and the electrostatic latent image on the latent image carrier 10 is developed and visualized. The latent image carrier contact charging member 11 is in contact with the latent image carrier 10. The bias of the latent image carrier contact charging member 11 is applied by a power source 12.

  The toner carrier 14 is horizontally provided with the substantially right half-periphery surface shown in the drawing through the opening into the developer container 23 and the left substantially half-periphery surface exposed outside the developer container 23. The surface exposed to the outside of the developer container 23 is in contact with the latent image carrier 10 located on the left side of the developing unit 13 as shown in FIG.

  The toner carrier 14 is rotationally driven in the direction of arrow B, the peripheral speed of the latent image carrier 10 is 50 to 170 mm / s, and the peripheral speed of the toner carrier 14 is 1 to 2 with respect to the peripheral speed of the latent image carrier 10. It is rotating at twice the peripheral speed.

  At a position above the toner carrier 14, a metal plate such as SUS, a rubber material such as urethane or silicone, a metal thin plate of SUS or phosphor bronze having spring elasticity, and a contact surface side to the toner carrier 14. A restricting member 16 made of a rubber material and the like is supported on the restricting member support metal plate 24 and is provided so that the vicinity of the free end side is in contact with the outer peripheral surface of the toner carrying member 14 by surface contact. The contact direction is a so-called counter direction in which the tip side with respect to the contact portion is located upstream of the rotation direction of the toner carrier 14. As an example of the regulating member 16, a plate-like urethane rubber having a thickness of 1.0 mm is bonded to the regulating member support sheet metal 24, and the contact pressure (linear pressure) with respect to the toner carrier 14 is appropriately set. is there. The contact pressure is preferably 20 to 300 N / m. The measurement of the contact pressure is converted from a value obtained by inserting three metal thin plates with known friction coefficients into the contact portion and pulling out the central one with only a spring. The regulating member 16 having a rubber material or the like bonded to the abutting surface is desirable in terms of adhesion to the toner, and can suppress the fusion and fixing of the toner to the regulating member in long-term use. Further, the restricting member 16 may be in contact with the toner carrier 14 by edge contact in which the tip is contacted. In the case of edge contact, it is more desirable in terms of toner layer regulation to set the contact angle of the regulating member with respect to the tangent of the toner carrying body at the contact with the toner carrying body to be 40 degrees or less.

  The toner supply roller 15 is in contact with the contact portion of the regulating member 16 with the surface of the toner carrier 14 on the upstream side in the rotation direction of the toner carrier 14 and is rotatably supported. The contact width of the toner supply roller 15 with respect to the toner carrier 14 is preferably 1 to 8 mm, and it is preferable that the toner carrier 14 has a relative speed at the contact portion.

  The charging roller 29 is not essential for the image forming method of the present invention, but is preferably installed. The charging roller 29 is an elastic body such as NBR or silicone rubber, and is attached to the suppression member 30. The contact load of the charging roller 29 on the toner carrier 14 by the suppressing member 30 is set to 0.49 to 4.9N. By the contact of the charging roller 29, the toner layer on the toner carrier 14 is finely packed and uniformly coated. The longitudinal positional relationship between the regulating member 16 and the charging roller 29 is preferably arranged so that the charging roller 29 can reliably cover the entire contact area of the regulating member 16 on the toner carrier 14.

  For driving the charging roller 29, it is essential to follow or have the same peripheral speed with the toner carrier 14. If a peripheral speed difference occurs between the charging roller 29 and the toner carrier 14, the toner coat becomes uneven. This is not preferable because unevenness occurs on the image.

  A bias of the charging roller 29 is applied by a power source 27 between the toner carrier 14 and the latent image carrier 10 in a direct current (27 in FIG. 3), and the nonmagnetic toner 17 on the toner carrier 14 is charged by the charging roller. From 29, charge is applied by discharge.

  The bias of the charging roller 29 is equal to or higher than the discharge start voltage having the same polarity as that of the non-magnetic toner, and is set so that a potential difference of 1000 to 2000 V is generated with respect to the toner carrier 14.

  After being charged by the charging roller 29, the toner layer formed as a thin layer on the toner carrier 14 is uniformly conveyed to a developing unit that is a portion facing the latent image carrier 10.

  In this developing unit, the toner layer formed as a thin layer on the toner carrier 14 is transferred to the latent image by a DC bias applied between the toner carrier 14 and the latent image carrier 10 by the power source 27 shown in FIG. The electrostatic latent image on the carrier 10 is developed as a toner image.

  Hereinafter, the present invention will be specifically described with reference to production examples and examples, but this does not limit the present invention in any way. In the examples and comparative examples, all parts and% are based on mass unless otherwise specified.

  A production example of the toner and toner carrier used in the image forming method of the present invention will be described.

(Production example of polar polymer)
In a pressurizable reaction vessel equipped with a reflux tube, a stirrer, a thermometer, a nitrogen introduction tube, a dropping device and a decompression device, 250 parts of methanol as a solvent, 150 parts of 2-butanone and 100 parts of 2-propanol, styrene as a monomer 92.5 parts, 5 parts of 2-ethylhexyl acrylate, and 2.5 parts of 2-acrylamido-2-methylpropanesulfonic acid were added and heated to reflux temperature with stirring. A solution obtained by diluting 4.0 parts of t-butylperoxy-2-ethylhexanoate as a polymerization initiator with 20 parts of 2-butanone was added dropwise over 30 minutes, and stirring was continued for 4 hours. Further, t-butylperoxy was further added. A solution prepared by diluting 0.40 part of 2-ethylhexanoate with 20 parts of 2-butanone was added dropwise over 30 minutes, and the mixture was further stirred for 5 hours to complete the polymerization.

  The polymer obtained after the polymerization solvent was distilled off under reduced pressure was coarsely pulverized to 100 μm or less using a cutter mill equipped with a 100 μm screen. The obtained polymer is designated as polar polymer 1.

<Manufacture of toner>
(Toner Production Example 1)
3 parts of tricalcium phosphate was added to 900 parts of ion-exchanged water heated to 65 ° C., and stirred at 10,000 rpm using a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.) to obtain an aqueous medium.

on the other hand,
Styrene 79 parts n-butyl acrylate 21 parts Saturated polyester resin 4.5 parts (Polycondensate of propylene oxide modified bisphenol A and terephthalic acid,
Tg = 65 ° C., Mn = 5000, Mw / Mn = 2.4)
Polar polymer 1 1 part Aluminum salicylate compound 1 part (Bontron E-88, manufactured by Orient Chemical Co., Ltd.)
C. I. Pigment Blue 15: 3 10 parts The above formulation was uniformly dispersed and mixed using an attritor (Mitsui Miike Chemical Co., Ltd.). This monomer composition was heated to 65 ° C., and 9 parts of an ester wax mainly composed of stearyl stearate (maximum endothermic peak 67 ° C. in DSC measurement) was added and dissolved therein. 3.5 parts by mass of 2′-azobis-2-methylpropionitrile (10 hour half-life temperature 65 ° C.) was dissolved.

The polymerizable monomer system was put into the aqueous medium, and the mixture was granulated by stirring at 10,000 rpm for 10 minutes with a TK homomixer in an N ₂ atmosphere at 70 ° C. Thereafter, the mixture was reacted at 65 ° C. for 7 hours while stirring with a paddle stirring blade. Thereafter, the liquid temperature was raised to 80 ° C., and stirring was further continued for 4 hours. After completion of the reaction, the suspension was cooled at a cooling rate of −5 ° C./min.

  Hydrochloric acid was added to the suspension cooled to room temperature (25 ° C.) to dissolve the calcium phosphate salt, followed by filtration and washing with water to obtain wet colored particles.

  Next, the particles were dried at 40 ° C. for 12 hours to obtain colored particles (toner particles) having a number average particle diameter (D1) of 6.38 μm.

  The toner particles are classified by air classification into toner particles (toner particles F) having a number average particle size (D1) of 3.70 μm, toner particles (toner particles M) having a number average particle size (D1) of 5.95 μm, and number average particles. The toner particles (toner particles G) having a diameter (D1) of 6.64 μm were divided into three. The toner particles F4 kg were reslurried with 10 kg of ion exchange water, filtered, and washed 7 times with the same amount of ion exchange water. Thereafter, after drying again at 40 ° C. for 12 hours, the toner particles M and the toner particles G were uniformly mixed to obtain cyan toner particles 1.

100 parts of the toner particles and 0.7 part of hydrophobic silica fine powder having a BET value of 200 m ² / g treated with silicone oil and a primary particle size of 12 nm are mixed with a Henschel mixer (Mitsui Miike Chemical Co., Ltd.). The cyan toner 1 having a number average particle diameter (D1) of 6.24 μm (volume average particle diameter (D4) of 6.80 μm) was obtained.

  The cyan toner 1 was classified into cyan toner 1 (F) having a small number average particle diameter (D1) of 5.46 μm by wind classification (elbow jet classification apparatus EJ-L-3: manufactured by Nippon Steel Mining). The toner was divided into cyan toner 1 (G) having a number average particle diameter (D1) of 6.51 μm and a large particle diameter. Then, the amount of oxycarboxylic acid was quantified by the method described later, and the oxycarboxylic acid masses Bf and Bg of cyan toner 1 (F) and cyan toner 1 (G) were determined, and the ratio (Bf / Bg) was calculated.

  Table 1 shows the physical properties of Cyan Toner 1.

(Toner Production Example 2)
As a colorant, C.I. I. Instead of using 10 parts of Pigment Blue 15: 3, C.I. I. A yellow toner 2 was produced in the same manner as in Toner Production Example 1 except that 10 parts of Pigment Yellow 17 was used.

  Table 1 shows the physical properties of Yellow Toner 2.

(Toner Production Example 3)
As a colorant, C.I. I. Instead of using 10 parts of Pigment Blue 15: 3, C.I. I. Magenta toner 3 was produced in the same manner as in Toner Production Example 1 except that 16 parts of Pigment Red 122 were used.

  Table 1 shows the physical properties of Magenta Toner 3.

(Toner Production Example 4)
As a colorant, C.I. I. Pigment Blue 15: 3 in place of using 10 parts of carbon black (DBP oil absorption of 42cm ^3/100 g, a specific surface area of 60 m ² / g) except for using 16 parts of the black toner 4 in the same manner as in Toner Production Example 1 Manufactured.

  Table 1 shows the physical properties of the black toner 4.

(Toner Production Example 5)
100 parts of the cyan toner particles 1 obtained in Toner Production Example 1 and 0.7 part of hydrophobic silica fine powder having a BET value of 200 m ² / g treated with silicone oil and a primary particle size of 12 nm are Henschel. After mixing with a mixer (Mitsui Miike Chemical Co., Ltd.), the particle size is adjusted by air classification, and the cyan toner having a number average particle size (D1) of 6.30 μm (volume average particle size (D4) of 6.50 μm). 5 was obtained.

  The cyan toner 5 is subjected to air classification, and the cyan toner 5 (F) having a small number average particle diameter (D1) of 5.51 μm and the cyan toner having a large number average particle diameter (D1) of 6.57 μm are large. Divide into 5 (G). Then, the amount of oxycarboxylic acid was quantified by the method described later, and the oxycarboxylic acid masses Bf and Bg of cyan toner 5 (F) and cyan toner 5 (G) were determined, respectively, and the ratio (Bf / Bg) was calculated.

  Table 1 shows the physical properties of Cyan Toner 5.

(Toner Production Example 6)
100 parts of the cyan toner particles 1 obtained in Toner Production Example 1 and 0.7 part of hydrophobic silica fine powder having a BET value of 200 m ² / g treated with silicone oil and a primary particle size of 12 nm are Henschel. After mixing with a mixer (Mitsui Miike Chemical Co., Ltd.), the particle size is adjusted by air classification, and the number average particle size (D1) is 5.50 μm (volume average particle size (D4) is 7.30 μm). 6 was obtained.

  The cyan toner 6 is subjected to air classification, and the cyan toner 6 (F) having a small number average particle diameter (D1) of 4.81 μm and the cyan toner having a large particle diameter of 5.74 μm and a number average particle diameter (D1) are large. Divide into 6 (G). Then, the amount of oxycarboxylic acid was determined by the method described later, and the oxycarboxylic acid masses Bf and Bg of the cyan toner 6 (F) and cyan toner 6 (G) were determined, respectively, and the ratio (Bf / Bg) was calculated.

  Table 1 shows the physical properties of Cyan Toner 6.

(Toner Production Example 7)
By the same operation as in Toner Production Example 1, colored particles (toner particles) having a number average particle diameter (D1) of 6.38 μm are obtained.

  The toner particles are classified by air classification into toner particles (toner particles F) having a number average particle size (D1) of 3.70 μm, toner particles (toner particles M) having a number average particle size (D1) of 5.95 μm, and number average particles. The toner particles (toner particles G) having a diameter (D1) of 6.64 μm were divided into three. The toner particles F4 kg were reslurried with 10 kg of ion exchange water, filtered, and washed 5 times with the same amount of ion exchange water. Thereafter, after drying again at 40 ° C. for 12 hours, the toner particles M and the toner particles G were uniformly mixed to obtain cyan toner particles 7.

100 parts of the toner particles and 0.7 part of hydrophobic silica fine powder having a BET value of 200 m ² / g treated with silicone oil and a primary particle size of 12 nm are mixed with a Henschel mixer (Mitsui Miike Chemical Co., Ltd.). The cyan toner 7 having a number average particle diameter (D1) of 6.24 μm (volume average particle diameter (D4) of 6.80 μm) was obtained.

  The cyan toner 7 is subjected to air classification, and the cyan toner 7 (F) having a small number average particle diameter (D1) of 5.46 μm and the cyan toner having a large number average particle diameter (D1) of 6.51 μm are large. Divide into 7 (G). Then, the amount of oxycarboxylic acid was quantified by the method described later, and the oxycarboxylic acid masses Bf and Bg of cyan toner 7 (F) and cyan toner 7 (G) were determined, respectively, and the ratio (Bf / Bg) was calculated.

  Table 1 shows the physical properties of Cyan Toner 7.

(Toner Production Example 8)
By the same operation as in Toner Production Example 1, colored particles (toner particles) having a number average particle diameter (D1) of 6.38 μm are obtained.

  The toner particles are classified by air classification into toner particles (toner particles F) having a number average particle size (D1) of 3.70 μm, toner particles (toner particles M) having a number average particle size (D1) of 5.95 μm, and number average particles. The toner particles (toner particles G) having a diameter (D1) of 6.64 μm were divided into three. Then, 4 kg of toner particles F were reslurried with 10 kg of ion exchange water, filtered, and washed three times with the same amount of ion exchange water. Thereafter, after drying again at 40 ° C. for 12 hours, the toner particles M and the toner particles G were uniformly mixed to obtain cyan toner particles 8.

100 parts of the toner particles and 0.7 part of hydrophobic silica fine powder having a BET value of 200 m ² / g treated with silicone oil and a primary particle size of 12 nm are mixed with a Henschel mixer (Mitsui Miike Chemical Co., Ltd.). The cyan toner 8 having a number average particle diameter (D1) of 6.24 μm (volume average particle diameter (D4) of 6.80 μm) was obtained.

  The cyan toner 8 is subjected to air classification, and the cyan toner 8 (F) having a small number average particle diameter (D1) of 5.46 μm and the cyan toner having a large particle diameter of 6.51 μm and a number average particle diameter (D1) are large. Divide into 8 (G). Then, the amount of oxycarboxylic acid was quantified by the method described later, and the oxycarboxylic acid masses Bf and Bg of cyan toner 8 (F) and cyan toner 9 (G) were determined, respectively, and the ratio (Bf / Bg) was calculated.

  Table 1 shows the physical properties of Cyan Toner 8.

(Toner Production Example 9)
A cyan toner 9 was obtained by the same operation except that the polar polymer 1 was not used in Toner Production Example 1.

  The cyan toner 9 is subjected to air classification, and a cyan toner 9 (F) having a small number average particle diameter (D1) of 5.46 μm and a cyan toner having a large number average particle diameter (D1) of 6.51 μm are large. Divide into 9 (G). Then, the amount of oxycarboxylic acid was quantified by the method described later, and the oxycarboxylic acid masses Bf and Bg of cyan toner 9 (F) and cyan toner 9 (G) were determined, respectively, and the ratio (Bf / Bg) was calculated.

  Table 1 shows the physical properties of Cyan Toner 9.

(Toner Production Example 10)
A cyan toner 10 was obtained in the same manner as in Toner Production Example 1 except that no aluminum salicylate compound was used.

  The cyan toner 10 is subjected to air classification, and the cyan toner 10 (F) having a small number average particle diameter (D1) of 5.46 μm and the cyan toner having a large number average particle diameter (D1) of 6.51 μm are large. Divide into 10 (G). Then, the amount of oxycarboxylic acid was quantified by the method described later, and the oxycarboxylic acid masses Bf and Bg of cyan toner 10 (F) and cyan toner 10 (G) were determined, respectively, and the ratio (Bf / Bg) was calculated.

  Table 1 shows the physical properties of the cyan toner 10.

(Toner Production Example 11)
A cyan toner 11α having a number average particle diameter (D1) of 6.24 μm was obtained in the same manner as in Toner Production Example 1 except that 1.4 parts of an aluminum salicylate compound was used. The cyan toner 11α is subjected to air classification and the cyan toner 11α (F) having a small number average particle diameter (D1) of 5.46 μm and the cyan toner 11α having a large number average particle diameter (D1) of 6.51 μm are large. Divided into (G). Then, cyan toner 1 (F) having a number average particle diameter (D1) of 5.46 μm obtained in Toner Production Example 1 and cyan toner 11α (G) are uniformly mixed to obtain cyan toner 11. Obtained.

(Toner Production Example 12)
A cyan toner 12α having a number average particle diameter (D1) of 6.24 μm was obtained in the same manner as in Toner Production Example 1 except that 0.3 part of an aluminum salicylate compound was used. The cyan toner 12α is subjected to air classification and the cyan toner 12α (F) having a small number average particle size (D1) of 5.46 μm and the cyan toner 12α having a large number average particle size (D1) of 6.51 μm are large. Divided into (G). Then, cyan toner 1 (G) having a number average particle diameter (D1) of 6.51 μm obtained in Toner Production Example 1 and cyan toner 12α (F) are uniformly mixed to obtain cyan toner 12. Obtained.

(Toner Production Example 13)
A cyan toner 13α having a number average particle diameter (D1) of 6.24 μm was obtained in the same manner as in Toner Production Example 1 except that 0.5 part of an aluminum salicylate compound was used. The cyan toner 13α is subjected to air classification, and the cyan toner 13α (F) having a small number average particle diameter (D1) of 5.46 μm and the cyan toner 13α having a large number average particle diameter (D1) of 6.51 μm are large. Divided into (G). Then, cyan toner 1 (G) having a number average particle diameter (D1) of 6.51 μm obtained in Toner Production Example 1 and cyan toner 13α (F) are uniformly mixed to obtain cyan toner 13. Obtained.

(Toner Production Example 14)
・ Styrene / butyl acrylate copolymer produced by solution polymerization method (glass transition temperature: 65 ° C., weight average molecular weight: 12500, Mw / Mn: 2.4) 100 parts Styrene / acrylic acid copolymer (glass transition temperature: 59 ° C., weight average molecular weight: 573,000, Mw / Mn: 2.0) 100 parts Aluminum salicylate compound (Bontron E-88; manufactured by Orient Chemical Co., Ltd.) 4 parts -Polar polymer 1 4 parts-C.I. I. Pigment Blue 15: 3 7 parts The above materials are mixed in a blender, melt kneaded with a biaxial extruder heated to 110 ° C., the cooled kneaded product is coarsely pulverized with a hammer mill, and the coarsely pulverized product is turbo milled (Turbo Industries). After finely pulverizing the product, the obtained finely pulverized product was subjected to air classification to obtain colored particles having a number average particle diameter (D1) of 7.43 μm.

  The toner particles are classified by air classification into toner particles (toner particles F) having a number average particle diameter (D1) of 4.70 μm, toner particles (toner particles M) having a number average particle diameter (D1) of 6.95 μm, and number average particles. The toner particles (toner particles G) having a diameter (D1) of 7.64 μm were divided into three. Then, 4 kg of toner particles F were reslurried with 10 kg of ion exchange water, filtered, and washed 9 times with the same amount of ion exchange water. Then, after drying at 40 ° C. for 12 hours, the toner particles M and the toner particles G were uniformly mixed to obtain cyan toner particles 14.

100 parts of the toner particles and 0.7 part of hydrophobic silica fine powder having a BET value of 200 m ² / g treated with silicone oil and a primary particle size of 12 nm are mixed with a Henschel mixer (Mitsui Miike Chemical Co., Ltd.). The cyan toner 14 having a number average particle diameter (D1) of 5.50 μm (volume average particle diameter (D4) of 7.00 μm) was obtained.

  The cyan toner 14 is air-classified, and the cyan toner 14 (F) having a small number average particle diameter (D1) of 5.46 μm and the cyan toner having a large number average particle diameter (D1) of 6.51 μm are large. 14 (G), and the amount of oxycarboxylic acid is determined by the method described later to determine the oxycarboxylic acid masses Bf and Bg of cyan toner 14 (F) and cyan toner 14 (G), respectively, and the ratio ( Bf / Bg) was calculated.

  Table 1 shows the physical properties of the cyan toner 14.

(Toner Production Example 15)
Styrene / n-butyl acrylate copolymer (mass ratio: 80/20) 200 parts Aluminum salicylate compound (Bontron E-88; manufactured by Orient Chemical Co., Ltd.) 8 parts Polar polymer 1 8 parts Stearyl stearate wax ( DSC main peak: 60 ° C.) 18 parts hydrocarbon wax (manufactured by Nippon Seisakusha; HNP-10, DSC main peak: 75 ° C.)
5 parts I. Pigment Blue 15: 3 7 parts The above materials are mixed in a blender, melt kneaded with a biaxial extruder heated to 110 ° C., the cooled kneaded product is coarsely pulverized with a hammer mill, and the coarsely pulverized product is turbo milled (Turbo Industries). After finely pulverizing, the obtained finely pulverized product was subjected to air classification to obtain colored particles having a number average particle diameter (D1) of 6.38 μm.

  The toner particles are classified by air classification into toner particles (toner particles F) having a number average particle size (D1) of 3.70 μm, toner particles (toner particles M) having a number average particle size (D1) of 5.95 μm, and number average particles. The toner particles (toner particles G) having a diameter (D1) of 6.64 μm were divided into three. Then, 4 kg of toner particles F were reslurried with 10 kg of ion exchange water, filtered, and washed 9 times with the same amount of ion exchange water. Thereafter, after drying at 40 ° C. for 12 hours, the toner particles M and the toner particles G were uniformly mixed to obtain cyan toner particles 15.

100 parts of the toner particles and 0.7 part of hydrophobic silica fine powder having a BET value of 200 m ² / g treated with silicone oil and a primary particle size of 12 nm are mixed with a Henschel mixer (Mitsui Miike Chemical Co., Ltd.). The cyan toner 15 having a number average particle diameter (D1) of 6.24 μm (volume average particle diameter (D4) of 6.80 μm) was obtained.

  The cyan toner 15 is air-classified, and the cyan toner 15 (F) having a small number average particle diameter (D1) of 5.46 μm and the cyan toner having a large number average particle diameter (D1) of 6.51 μm are large. The amount of oxycarboxylic acid is divided into 15 (G), and the amount of oxycarboxylic acid is determined by the method described later to determine the oxycarboxylic acid masses Bf and Bg of cyan toner 15 (F) and cyan toner 15 (G), respectively, and the ratio ( Bf / Bg) was calculated.

  Table 1 shows the physical properties of the cyan toner 15.

(Toner Production Example 16)
Cyan toner 16 was obtained in the same manner as in Toner Production Example 1 except that the number of parts of polar polymer 1 was changed to 0.3 parts and the number of parts of aluminum salicylate compound was changed to 0.3 parts.

  The cyan toner 16 is subjected to air classification, and the cyan toner 16 (F) having a small number average particle diameter (D1) of 5.46 μm and the cyan toner having a large number average particle diameter (D1) of 6.51 μm are large. Divided into 16 (G). Then, the amount of oxycarboxylic acid was quantified by the method described later, and the oxycarboxylic acid masses Bf and Bg of the cyan toner 16 (F) and cyan toner 16 (G) were determined, and the ratio (Bf / Bg) was calculated.

  Table 1 shows the physical properties of the cyan toner 16.

(Toner Production Example 17)
Cyan toner 17 was obtained in the same manner as in Toner Production Example 1 except that the number of parts of polar polymer 1 was changed to 0.3 parts and that of aluminum salicylate compound was changed to 0.3 parts.

  The cyan toner 17 is air-classified, and the cyan toner 17 (F) having a small number average particle diameter (D1) of 5.46 μm and the cyan toner having a large number average particle diameter (D1) of 6.51 μm are large. Divided into 17 (G). Then, the amount of oxycarboxylic acid was quantified by the method described later, and the oxycarboxylic acid masses Bf and Bg of cyan toner 17 (F) and cyan toner 17 (G) were determined, and the ratio (Bf / Bg) was calculated. .

  Table 1 shows the physical properties of the cyan toner 17.

(Toner Production Example 18)
By the same operation as in Toner Production Example 1, colored particles (toner particles) having a number average particle diameter (D1) of 6.38 μm are obtained.

  The toner particles are classified by air classification into toner particles (toner particles F) having a number average particle size (D1) of 3.70 μm, toner particles (toner particles M) having a number average particle size (D1) of 5.95 μm, and number average particles. The toner particles (toner particles G) having a diameter (D1) of 6.64 μm were divided into three. The toner particles F4 kg were reslurried with 10 kg of ion exchange water, filtered, and washed once with the same amount of ion exchange water. Thereafter, after drying again at 40 ° C. for 12 hours, the toner particles M and the toner particles G were uniformly mixed to obtain cyan toner particles 18.

100 parts of the toner particles and 0.7 part of hydrophobic silica fine powder having a BET value of 200 m ² / g treated with silicone oil and a primary particle size of 12 nm are mixed with a Henschel mixer (Mitsui Miike Chemical Co., Ltd.). The cyan toner 18 having a number average particle diameter (D1) of 6.24 μm (volume average particle diameter (D4) of 6.80 μm) was obtained.

  The cyan toner 18 is air-classified, and the cyan toner 18 (F) having a small number average particle diameter (D1) of 5.46 μm and the cyan toner having a large number average particle diameter (D1) of 6.51 μm are large. Divided into 18 (G). Then, the amount of oxycarboxylic acid was quantified by the method described later, and the oxycarboxylic acid masses Bf and Bg of the cyan toner 18 (F) and cyan toner 18 (G) were obtained, respectively, and the ratio (Bf / Bg) was calculated.

  Table 1 shows the physical properties of the cyan toner 18.

(Evaluation method of toner physical properties)
[Average circularity]
The average circularity in the present invention is used as a simple method for quantitatively expressing the shape of the particles, and is obtained for each particle according to the following formula (1) for a particle group having a circle equivalent diameter of 3 μm or more. It is a value obtained by dividing the sum of all the particles of circularity (ai) by the total number of particles (m).

  The circularity, the average circularity, and the mode circularity can be obtained from a particle image of toner particles. In the present invention, the measurement can be performed using a flow type particle image analyzer “FPIA-1000” manufactured by Toa Medical Electronics.

  The measurement method is as follows. A dispersion is prepared by dispersing 5 mg of toner in 10 ml of water in which about 0.1 mg of a surfactant is dissolved, and ultrasonic waves (20 kHz, 50 W) are irradiated to the dispersion for 5 minutes, and the dispersion concentration is set to 5000 to 2 The number of particles / μl is measured by the above apparatus, and the average circularity and mode circularity of a particle group having an equivalent circle diameter of 3 μm or more are obtained.

  The average circularity in the present invention is an index of the degree of unevenness of the toner particles, and indicates 1.000 when the toner is a perfect sphere, and the circularity becomes smaller as the surface shape becomes more complicated.

  In this measurement, the reason for measuring the circularity only for the particle group having an equivalent circle diameter of 3 μm or more is as follows. The particle group having an equivalent circle diameter of less than 3 μm includes a large number of particle groups of external additives that exist independently of the toner particles. Therefore, when the object to be measured is expanded to less than 3 μm, the effect of the toner particles This is because the circularity of the group cannot be estimated accurately.

[Average toner particle size]
The volume average particle size (D4) and the number average particle size (D1) of the toner of the present invention are measured by various known particle size measuring devices such as Coulter Counter TA-II type or Coulter Multisizer (manufactured by Coulter Co.). Is possible. Specifically, it can be measured as follows.

  Using a Coulter Multisizer (manufactured by Coulter), an interface (manufactured by Nikka) and a PC 9801 personal computer (manufactured by NEC) are connected to output the number distribution and volume distribution. As the electrolytic solution, a 1% NaCl aqueous solution prepared using primary sodium chloride can be used. For example, ISOTON R-II (manufactured by Coulter Scientific Japan) can be used. The measurement procedure is as follows.

  2 to 20 mg of a measurement sample is added to 100 to 150 ml of the electrolytic solution. The electrolyte in which the sample is suspended is subjected to a dispersion process for about 1 to 3 minutes with an ultrasonic disperser, and the volume and number of toner particles having a size of 2 μm or more are measured with the Coulter Multisizer using a 100 μm aperture. Calculate the distribution. From this, the volume average particle diameter (D4) and the number average particle diameter (D1) are determined.

[Toner charge measurement]
To measure the charge amount of the toner, a charge amount measuring device “E-SPART ANALYZER MODEL EST-II” manufactured by Hosokawa Micron Corporation was used. More specifically, the particle diameter and the particle charge amount are measured simultaneously by the particle moving speed and the laser Doppler method in a sonic vibration in a direct current electric field, and the particle diameter and particle charge amount of 3000 toners are measured. The charge amount of the toner was determined from the value.

  Made of "DSP-138" (manufactured by Dowa Iron Powder Co., Ltd.) as an iron powder carrier under a temperature of 15 ° C and a relative humidity of 10%, a mixture obtained by adding 2 g of toner to 98 g of iron powder carrier is made of polyethylene having a capacity of 50 to 100 ml. And leave it for 12 hours. Next, using a Yayoi-type shaker (model TS-LD; manufactured by Yayoi Co., Ltd.), what was shaken for 1 minute at a rotation speed of 1 minute was measured with the above measuring device, and Q / M ( The charge amount per unit mass, mC / kg) was determined. Further, a 10% number average particle diameter (D (10)) is obtained from the obtained data (CSV file), and a charge amount range of −120 mC / kg ≦ Q / M ≦ 0 mC / kg is obtained for a toner having the particle diameter or less. The number% of the toner having was obtained.

[Measurement of amount of oxycarboxylic acid in toner]
The amount of oxycarboxylic acid in the toner is measured by measuring the amount of oxycarboxylic acid A extracted from 0.1 g / liter of a sodium hydroxide aqueous solution from 1 g of toner, and is measured by the following method.

  That is, 50 ml of a 0.1 mol / liter aqueous sodium hydroxide solution containing 0.04 g of contamination is added as a dispersing agent, 1 g of toner is weighed and added, and stirred at 50 rpm using a stirrer to uniformly disperse. After the dispersion treatment for 3 hours, the mixture is filtered using a membrane filter (pore size: 0.45 μm), and the absorbance of the obtained filtrate is measured. By using a predetermined calibration curve from the obtained results, the mass A (mg) of oxycarboxylic acid extracted from 1 g of toner with a 0.1 mol / liter sodium hydroxide aqueous solution can be obtained.

<Manufacture of toner carrier>
(Polyether polyol (BO) having a unit represented by Formula 1)
100 parts of polytetramethylene glycol (trade name: PTG1000SN; molecular weight Mn = 1000; f = 2; manufactured by Hodogaya Chemical Co., Ltd.) and isocyanate (trade name: Millionate MT; MDI, f = 2; manufactured by Nippon Polyurethane Industry Co., Ltd.) ) 18.7 parts were mixed stepwise in a MEK solvent and reacted at 80 ° C. for 3 hours under a nitrogen atmosphere to obtain a bifunctional polyether polyol prepolymer having a molecular weight Mw = 10000 and a hydroxyl value of 18.2. -Polyol (1) was obtained.

Moreover, the following were prepared as polyol (2)-(6).
TE5042 (Mitsui Takeda Chemical Co., Ltd.) 2.2 Functional polyether polyol ... Polyol (2)
(Polyether polyol (PO) having a unit represented by Formula 2)
LB385 (manufactured by Sanyo Chemical Industries) Monofunctional polyether polyol ... polyol (3)
G100 (Mitsui Takeda Chemical Co., Ltd.) Trifunctional polyether polyol ... Polyol (4)
(Polyether polyol (EO) having a unit represented by Formula 3)
poly (ethylene glycol) methyl ether (PEME) (manufactured by Ardrich) monofunctional polyether polyol ... polyol (5)
(Polyether polyol (PO-EO) having units represented by Formula 2 and Formula 3 simultaneously)
HB260 (manufactured by Sanyo Chemical Industries) Monofunctional polyether polyol ... polyol (6)

(Production Example A of Toner Carrier)
A core metal (shaft) having an outer diameter of 8 mm is placed concentrically in a cylindrical mold having an inner diameter of 16 mm, and a liquid conductive silicone rubber (manufactured by Toray Dow Corning Silicone Co., Ltd.) is used as a material for forming the conductive elastic layer. ASKER-C hardness 45 degrees, volume resistivity 1 × 10 ⁷ Ω · cm product), put into 130 ° C oven, heat-molded for 20 minutes, demolded, and then secondarily applied in 200 ° C oven for 4 hours Sulfur was performed to form a conductive elastic layer having a thickness of 4 mm.
Polyol (1) 100 parts Polyol (3) 3.1 parts Polyol (5) 2 parts Isocyanate C2521 (Nippon Polyurethane Industry Co., Ltd., solid content 65%) 125 parts Methyl ethyl ketone is added to the above raw material mixture and the solid content is 25 to 30% by mass. What was adjusted so that it might become was used as the raw material liquid for conductive resin layer formation. 20 parts of carbon black MA230 (manufactured by Mitsubishi Chemical Corporation) and 15 parts of acrylic particles MX-1000 (manufactured by Soken Chemical Co., Ltd.) were added to the solid content of the raw material liquid, and this paint liquid was stirred and dispersed with a ball mill. The paint is applied on the conductive elastic layer previously molded by dipping so as to have a film thickness of 15 μm, dried in an oven at 80 ° C. for 15 minutes, and then cured in an oven at 140 ° C. for 4 hours to form a conductive resin as a surface layer. A toner carrier A having a layer was obtained.

(Production Example B of Toner Carrier)
Toner carrier B was obtained in the same manner except that the composition of the polyol and isocyanate used in Production Example A of the toner carrier was changed as follows.
Polyol (1) 79.3 parts Polyol (2) 39.7 parts Polyol (6) 47.6 parts Isocyanate C2521 (Nihon Polyurethane Industry Co., Ltd. solid content 65%) 213.3 parts

(Production example C of toner carrier)
Toner carrier C was obtained in the same manner except that the blending of the polyol and isocyanate used in Production Example A of the toner carrier was changed as follows.
Polyol (1) 124 parts Polyol (2) 61.9 parts Polyol (6) 9.3 parts Isocyanate C2521 (Nippon Polyurethane Industry Co., Ltd. solid content 65%) 187 parts

(Production Example D of toner carrier)
Toner carrier D was obtained in the same manner except that the blend of polyol and isocyanate used in Production Example A of the toner carrier was changed as follows.
Polyol (1) 89.2 parts Polyol (2) 44.6 parts Polyol (6) 22.7 parts Isocyanate C2521 (Nihon Polyurethane Industry Co., Ltd. solid content 65%) 154.9 parts

(Production Example E of Toner Carrier)
Toner carrier E was obtained in the same manner except that the blending of polyol and isocyanate used in Production Example A of the toner carrier was changed as follows.
Polyol (2) 100 parts Polyol (3) 25 parts Polyol (5) 20 parts Isocyanate C2521 (Nihon Polyurethane Industry Co., Ltd. solid content 65%) 172 parts

(Production Example F of Toner Carrier)
Toner carrier F was obtained in the same manner except that the blend of polyol and isocyanate used in Production Example A of the toner carrier was changed as follows.
Polyol (1) 100 parts Polyol (3) 2 parts Polyol (5) 1.5 parts Isocyanate C2521 (Nippon Polyurethane Industry Co., Ltd. solid content 65%) 139 parts

(Production example G of toner carrier)
A toner carrier G was obtained in the same manner except that the blending of the polyol and isocyanate used in the production example of the toner carrier A was changed as follows.
Polyol (2) 100 parts Polyol (3) 30 parts Polyol (5) 30 parts Isocyanate C2521 (Nihon Polyurethane Industry Co., Ltd. solid content 65%) 160 parts

(Production example H of toner carrier)
A toner carrier H was obtained in the same manner except that the blending of the polyol and isocyanate used in Production Example A of the toner carrier was changed as follows.
Polyol (1) 100 parts Polyol (6) 2 parts Isocyanate C2521 (Nihon Polyurethane Industry Co., Ltd. solid content 65%) 102 parts

(Production Example I of Toner Carrier)
Toner carrier I was obtained in the same manner except that the blending of polyol and isocyanate used in Production Example A of the toner carrier was changed as follows.
Polyol (2) 100 parts Polyol (6) 50 parts Isocyanate C2521 (Nihon Polyurethane Industry Co., Ltd. solid content 65%) 201.1 parts

(Production Example J of Toner Carrier (Comparative Production Example))
A toner carrier J was obtained in the same manner except that the blending of the polyol and isocyanate used in Production Example A of the toner carrier was changed as follows.
Polyol (2) 100 parts isocyanate C2521 (manufactured by Nippon Polyurethane Industry Co., Ltd., solid content 65%) 145 parts

(Production example K of toner carrier (comparative production example))
A toner carrier K was obtained in the same manner except that the blending of the polyol and isocyanate used in Production Example A of the toner carrier was changed as follows.
Polyol (4) 100 parts Polyol (5) 20.1 parts Isocyanate C2521 (Nihon Polyurethane Industry Co., Ltd. solid content 65%) 120 parts

(Measurement of contact angle of toner carrier)
A contact angle meter CA-S ROLL manufactured by Kyowa Interface Co., Ltd. was used, and a 15 gauge gauge needle manufactured by Kyowa Interface Science Co., Ltd. was used. The liquid diameter in the droplet dropping direction was about 1.5 mm, and 10 points were dropped per surface of the developing roller image area in a normal temperature and humidity environment (23 ° C./65% RH), and the contact angle after 10 seconds was measured. . The average value of the contact angles of 8 points excluding the maximum value and the minimum value of 10 contact angles was rounded off. Table 2 shows the values measured for each toner carrier with ethylene glycol and diiodomethane.

<Manufacture of toner supply roller>
Next, an example of manufacturing a toner supply roller that can be used in the present invention will be described below. 90 parts of polyol (trade name: FA908, manufactured by Sanyo Chemical Industries), 10 parts of polyol (trade name: POP34-28, manufactured by Sanyo Chemical Industries), TOYOCAT-ET (trade name, manufactured by Tosoh Corporation, tertiary amine catalyst) ) 0.1 part, TOYOCAT-L33 (trade name manufactured by Tosoh Corporation, tertiary amine catalyst) 0.5 part, water (foaming agent) 2.5 part, SH190 (Toray Dow as silicone and polyether copolymer) 1 part of Corning Silicone trade name) was mixed in advance. Thereafter, 24 parts of Coronate 1021 (trade name, manufactured by Nippon Polyurethane Industry Co., Ltd., NCO% = 45) as a polyisocyanate was added to this mixture, mixed and stirred, and then foam-molded with the above-mentioned mold to obtain an outer diameter of 5 mm. A toner supply roller was prepared by integrally forming a foamed elastic layer made of polyurethane sponge having a thickness of 4.5 mm around the core metal.

◎ (Image evaluation)
The image evaluation was performed using an image forming apparatus as shown in FIGS. The toner, toner carrier, and toner supply roller were mounted on an electrophotographic process cartridge, and the cartridge was left in a high temperature and high humidity environment (40 ° C./95% RH) for 30 days. Then, after standing for 3 days in a normal temperature and normal humidity (23 ° C., 60% RH) environment, left in a low temperature and low humidity environment (15 ° C., 10% RH) for 1 day, and in that environment (low temperature and low humidity environment; LL). Image evaluation was performed (Table 3 described later). Furthermore, after the image evaluation was completed in a low-temperature and low-humidity (15 ° C., 10% RH) environment, the entire machine was left in a normal temperature and normal humidity (23 ° C., 60% RH) environment for 1 day, and then the entire machine was further heated and humidified ( The sample was left for 1 day in an environment of 30 ° C. and 80% RH, and image evaluation was continuously performed in the environment (high temperature and high humidity environment; HH) (Table 4 described later). The image evaluation items are as follows, and image evaluation of each environment was performed after printing 5000 images with a printing rate of 1% in the initial and horizontal lines.

  Further, 300 g of each toner was filled in the process cartridge, and the process speed was 300 mm / s. In addition, the machine has been improved so that it can operate even when only one color process cartridge is installed.

(Image evaluation items)
a) Image Density The image density was evaluated using the “Macbeth reflection densitometer” (manufactured by Macbeth Co., Ltd.) by measuring the relative density with respect to a printout image of a white background portion having a document density of 0.00 and evaluated according to the following criteria. .
A: Image density is 1.45 or more B: Image density is 1.30 or more and less than 1.45 C: Image density is 1.15 or more and less than 1.30 D: Image density is less than 1.15

  In evaluation, A is the best and D is the worst.

b) Fog For the measurement of the fog, the reflectance of the non-image part of the standard paper and the printout image was measured using a reflection densitometer manufactured by Tokyo Denshoku Co., Ltd. and REFECTECTOMER MODEL TC-6DS. As a filter used in the measurement, amber light was used for cyan, blue was used for yellow, and green filters were used for magenta and black. The fog was calculated from the measurement results by the following formula and evaluated according to the following criteria.
Fog (reflectance:%) = reflectance on standard paper (%) − reflectance of sample non-image area (%)
A: Fog (reflectance) is 1.0% or less B: Fog (reflectance) is more than 1.0 to 1.5% C: Fog (reflection) is more than 1.5 to 2.0% D ; Fog (reflectance) is over 2.0

  In evaluation, A is the best and D is the worst.

c) Resolution The resolution was evaluated based on the reproducibility of small-diameter isolated 1 dot at 600 dpi, which is easy to close due to the latent image electric field and difficult to reproduce.
A: Less than 5 defects in 100 B: 6-10 defects in 100 C: 11-20 defects in 100 D: More than 20 defects in 100

  In evaluation, A is the best and D is the worst.

d) Ghost For image evaluation regarding ghost, a solid black band was output for one round of the toner carrier, and then a halftone image was output. A schematic diagram of the pattern is shown in FIG. In the evaluation method, the Macbeth density at the place where the black image is formed on the second turn of the toner carrier (black print portion) and the place where the black image is not formed (non-image portion) in one print image. The difference in reflection density measured by a reflectometer was calculated as follows. A ghost image is an image of a portion where the image density of the black printed portion on the first round of the toner carrying member is a non-image portion on the first round of the toner carrying member. Unlike the density, this is a ghost phenomenon in which the shape of the pattern produced in the first round appears as it is. The density difference here was evaluated by measuring the reflection density difference.
Reflection density difference = | reflection density (place where no image is formed) −reflection density (place where an image is formed) |

The smaller the reflection density difference is, the better the level is without ghosting. As a comprehensive evaluation of ghosts, evaluation was performed in four stages of A, B, C, and D.
The value of the reflection density difference was the maximum density difference value.
A: Reflection density difference less than 0.02 B: Reflection density difference 0.02 or more and less than 0.04 C: Reflection density difference 0.04 or more and less than 0.06 D: Reflection density difference 0.06 or more

  In evaluation, A is the best and D is the worst.

e) Banding evaluation In the banding evaluation, a halftone image was output and the following evaluation was performed visually.
A: Banding is not recognized at all. B: Banding is very slight.
C: Banding is recognized.
D: Severe banding is recognized.

  In evaluation, A is the best and D is the worst.

  A to C are in a range where there is no practical problem, but D has a problem in practical use and is not in an allowable range.

Example 1
Evaluation was performed using toner carrier A and cyan toner 1. The evaluation results are shown in Tables 3 and 4.

(Example 2)
Evaluation was performed using toner carrier B and cyan toner 1. The evaluation results are shown in Tables 3 and 4.

(Example 3)
Evaluation was performed using toner carrier C and cyan toner 1. The evaluation results are shown in Tables 3 and 4.

Example 4
Evaluation was performed using toner carrier D and cyan toner 1. The evaluation results are shown in Tables 3 and 4.

(Example 5)
Evaluation was performed using toner carrier E and cyan toner 1. The evaluation results are shown in Tables 3 and 4.

(Example 6)
Evaluation was performed using toner carrier F and cyan toner 1. The evaluation results are shown in Tables 3 and 4.

(Example 7)
Evaluation was carried out using toner carrier G and cyan toner 1. The evaluation results are shown in Tables 3 and 4.

(Example 8)
Evaluation was carried out using toner carrier H and cyan toner 1. The evaluation results are shown in Tables 3 and 4.

Example 9
Evaluation was performed using toner carrier I and cyan toner 1. The evaluation results are shown in Tables 3 and 4.

(Example 10)
Evaluation was performed using toner carrier D and magenta toner 2. The evaluation results are shown in Tables 3 and 4.

(Example 11)
Evaluation was carried out using toner carrier D and yellow toner 3. The evaluation results are shown in Tables 3 and 4.

(Example 12)
Evaluation was carried out using toner carrier D and black toner 4. The evaluation results are shown in Tables 3 and 4.

(Example 13)
Evaluation was performed using toner carrier D and cyan toner 5. The evaluation results are shown in Tables 3 and 4.

(Example 14)
Evaluation was performed using toner carrier D and cyan toner 6. The evaluation results are shown in Tables 3 and 4.

(Example 15)
Evaluation was performed using toner carrier D and cyan toner 7. The evaluation results are shown in Tables 3 and 4.

(Example 16)
Evaluation was performed using toner carrier D and cyan toner 8. The evaluation results are shown in Tables 3 and 4.

(Example 17)
Evaluation was performed using toner carrier D and cyan toner 9. The evaluation results are shown in Tables 3 and 4.

(Example 18)
Evaluation was performed using toner carrier D and cyan toner 10. The evaluation results are shown in Tables 3 and 4.

Example 19
Evaluation was carried out using toner carrier D and cyan toner 11. The evaluation results are shown in Tables 3 and 4.

(Example 20)
Evaluation was performed using toner carrier D and cyan toner 12. The evaluation results are shown in Tables 3 and 4.

(Example 21)
Evaluation was carried out using toner carrier D and cyan toner 13. The evaluation results are shown in Tables 3 and 4.

(Example 22)
Evaluation was performed using toner carrier D and cyan toner 14. The evaluation results are shown in Tables 3 and 4.

(Comparative Example 1)
Evaluation was performed using toner carrier J and cyan toner 8. The evaluation results are shown in Tables 3 and 4.

(Comparative Example 2)
Evaluation was performed using toner carrier K and cyan toner 8. The evaluation results are shown in Tables 3 and 4.

(Comparative Example 3)
Evaluation was performed using toner carrier D and cyan toner 14. The evaluation results are shown in Tables 3 and 4.

(Comparative Example 4)
Evaluation was performed using toner carrier D and cyan toner 15. The evaluation results are shown in Tables 3 and 4.

(Comparative Example 5)
Evaluation was performed using toner carrier D and cyan toner 16. The evaluation results are shown in Tables 3 and 4.

(Comparative Example 6)
Evaluation was performed using toner carrier D and cyan toner 17. The evaluation results are shown in Table 3 and Table 4.

FIG. 3 is an axial sectional view showing an example of the developing roller of the present invention. FIG. 3 is an axial sectional view showing an example of the developing roller of the present invention. It is an enlarged view of the developing unit of the electrophotographic apparatus. 1 is a cross-sectional view of an electrophotographic apparatus using an image forming method of the present invention. It is the schematic of the pattern used for evaluation of a ghost.

Explanation of symbols

1: Highly conductive shaft (shaft)
2: conductive elastic layer 3: conductive resin layer 10: photosensitive drum 13: developing unit 14: toner carrier 15: toner supply roller 23: developer container 29: charging roller

Claims (17)

At least a toner carrier and a toner supply roller are brought into contact with the surface of the electrostatic latent image carrier directly or via toner, and the surface of the electrostatic latent image carrier by the toner carried by the toner carrier. An image forming method for developing an electrostatic latent image, comprising:
The toner carrier surface has a contact angle with ethylene glycol of 60 to 90 degrees and a contact angle with diiodomethane of 30 to 38 degrees,
The toner is a non-magnetic one-component contact developing toner having toner particles containing at least a binder resin and a colorant, and the toner has an average circularity of 0.940 or more and 0.995 or less. 80% of toners having a / M of −75 mC / kg to −25 mC / kg and a toner having a Q / M of −120 mC / kg to 0 mC / kg in a toner having a 10% number average diameter (D (10)) or less. An image forming method as described above.
Q / M: Charge amount per unit mass of toner   The image forming method according to claim 1, wherein the toner carrier includes at least a shaft body, a conductive elastic layer provided on the shaft body, and a conductive resin layer constituting an outermost layer. . The conductive resin layer has a urethane resin composed of an isocyanate component and a polyol component, the polyol component is a polyether polyol, and the polyether polyol is represented by the following formula (1)

(In the formula, l represents a positive integer.)
Unit represented by the following formula (2)

(In the formula, m represents a positive integer.)
And the following formula (3)

(In the formula, n represents a positive integer.)
The image forming method according to claim 2, further comprising a unit represented by:   The polyether polyol has a molar ratio of the unit (BO) represented by the above formula (1), the unit (PO) represented by the above formula (2), and the unit (EO) represented by the above formula (3). The image forming method according to claim 3, wherein BO: PO: EO = 100: 3: 2 to 100: 25: 20.   The urethane resin includes an isocyanate component, a polyol (BO) having a unit represented by the formula (1), and a polyol (PO-EO) having a unit represented by the formula (2) and the formula (3) at the same time. And the mass ratio of BO and (PO-EO) is BO: (PO-EO) = 100: 5 to 100: 40. 5. The image forming method according to 4.   The image forming method according to claim 4, wherein the polyol having a unit represented by the formula (1) has two or more hydroxyl groups.   The image forming method according to claim 4, wherein the polyol having a unit represented by the formula (2) has one hydroxyl group.   The image forming method according to claim 4, wherein the polyol having a unit represented by the formula (3) has one hydroxyl group.   The image forming method according to claim 5, wherein the polyol having the units represented by the formula (2) and the formula (3) simultaneously has one hydroxyl group.   10. The image forming method according to claim 1, wherein the toner has a volume average particle diameter (D4) / number average particle diameter (D1) in the range of 1.05 to 1.30.   11. The toner having a Q / M of −120 mC / kg to 0 mC / kg in a toner having a 10% number average diameter (D (10)) or less of the toner is 85% by number or more. The image forming method according to any one of the above.   11. The toner having a Q / M of −120 mC / kg to 0 mC / kg is 90% by number or more in a toner having a 10% number average diameter (D (10)) or less of the toner. The image forming method according to any one of the above.   The image forming method according to claim 1, wherein the toner contains a polymer or copolymer of a sulfonic acid group, a sulfonic acid group, or a sulfonic acid ester group.   14. The toner according to claim 1, wherein the toner contains an aromatic oxycarboxylic acid metal compound (Al, Zn, Cr, Co, Ni, Zr, Ti, Cu, Fe). Image forming method. When the toner is divided into two parts by a classifier, a toner (F) having a smaller number average particle diameter (D1) than the toner and a toner (G) having a larger number average particle diameter (D1) than the toner. The image forming method according to claim 14, wherein the following formula (4) is satisfied when the masses of the oxycarboxylic acids of (F) and (G) are Bf and Bg, respectively.
1.0 <Bf / Bg <2.5 (4) When the toner is divided into two parts by a classifier, a toner (F) having a smaller number average particle diameter (D1) than the toner and a toner (G) having a larger number average particle diameter (D1) than the toner. The image forming method according to claim 14, wherein the following formula (4) is satisfied when the masses of the oxycarboxylic acids of (F) and (G) are Bf and Bg, respectively.
1.0 <Bf / Bg <2.0 (5)   The toner supply roller includes a cored bar and a foamed elastic layer formed around the cored bar, and the foamed elastic layer contains a copolymer of silicone and polyether. The image forming method according to any one of 1 to 16.

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