JP2005181485A - Toner, image forming method, and process cartridge - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a toner having a flocculation process, suppresses the fogging accompanying the deterioration in durability and achieves low-temperature fixability. <P>SOLUTION: In the toner having flocculation process, the toner having the fastness and low-temperature fixability of the toner in combination is achieved, by controlling the toner, in such a manner that the toluene insoluble content thereof is 45%, that the main peak molecular weight of the toluene soluble content is 45,000 and 100,000, and that the molecular weight components lower than the peak molecular weight are distributed more than the high molecular weight components in the half-band width of the main peak is achieved. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a toner, an image forming method, and a process cartridge used in a recording method using an electrophotographic method, an electrostatic recording method, or the like. Specifically, a toner used in an image forming apparatus such as a copying machine, a printer, a fax machine, and the like that forms an image on a transfer material after forming a developer image on an electrostatic latent image carrier in advance, and an image forming method and process It relates to the cartridge.

  Equipment using electrophotography is applied to devices such as printers and fax machines in addition to conventional copying machines. Especially for printers and fax machines, the electrophotographic process unit needs to be small, and in order to facilitate maintenance, the developer unit centered on the development unit and the drum unit centered on the electrostatic latent image carrier are divided into two units. In addition, a process cartridge that integrates them has been increasingly used.

  As a developing method used for these process cartridges, there are many one-component developing methods advantageous for downsizing. The one-component developing method uses a one-component developer (hereinafter also referred to as “toner”), friction between a layer thickness regulating member (hereinafter also referred to as “blade”) and toner particles, and a developer carrier (hereinafter referred to as “developing roller”). Is also applied to the developing roller at the same time as a thin film on the developing roller by friction of the toner particles, and the toner is transported to a developing area where the developing roller and the electrostatic latent image carrier face each other. The electrostatic latent image on the image carrier is developed and visualized as a toner image.

  In this one-component development system, a contact development method is also widely performed in which development is performed by bringing an electrostatic latent image carrier and a developing roller into direct or indirect contact, and bringing a toner layer into contact with the electrostatic latent image carrier. . The contact development method is a development method excellent in fine line reproducibility, image density uniformity and the like, and is preferable as a means for achieving high image quality.

  On the other hand, as a recent mainstream, a system that eliminates oil that has been applied to improve the peelability of media at the time of fixing can achieve good prints without glare, and has been widely accepted especially in offices. As a toner suitable for these oil-less systems, a toner synthesized by a polymerization method is advantageous in that it can sufficiently contain a wax component. In particular, an agglomerated toner having irregularities on the surface, represented by the emulsion agglomeration method, has excellent cleaning properties and is advantageous for an electrophotographic system.

  In recent years, it has been desired to increase the speed and energy saving of office equipment, and the physical properties required for toners to meet these demands include low-temperature fixability higher than that of conventional toners.

As an effective method for achieving low-temperature fixability, a method of lowering the main peak molecular weight of the binder resin component of the toner has been proposed (see Patent Document 1).
However, when a large number of prints are repeated using an emulsion aggregation method toner composed of a binder resin component having a reduced main peak molecular weight, the deterioration of the toner progresses due to the brittleness of the binder component, and the fog is remarkably deteriorated. There has occurred.

  In order to solve the above problems, emulsion aggregation method toners have been proposed in which the peak molecular weight of the binder component is relatively high and the internally added wax has a low melting point (see Patent Documents 2 to 5).

  As a result of a trial evaluation of the above toner by a non-magnetic one-component machine, the present inventors have improved the low-temperature fixing performance by using a low-melting wax. However, when printing is repeated, the toner breaks unexpectedly. The fog became worse. As a result of the present inventors examining the cause of fog deterioration, the aggregate composition of the low melting point wax and the binder resin particles results in the toner becoming brittle. It can be presumed that fog due to deterioration such as toner surface exposure exceeds an allowable range.

As mentioned above, especially in toners that have an agglomeration process, achieving low-temperature fixability and suppressing deterioration of durability as much as possible to suppress deterioration of fog are reciprocal, and both of these exhibit high performance. The toner to be waited for was long-awaited.
Japanese Patent Laid-Open No. 2001-235894 JP 2001-209212 JP JP 2002-202624 A JP 2001-324833 A JP 2001-324834 A

  An object of the present invention has been made in view of the above problems, and in a toner having an aggregation process used for non-magnetic one-component development, a toner that suppresses fogging due to durability deterioration and achieves low-temperature fixability. It is to provide.

  Another object of the present invention is to provide an image forming method that suppresses fogging due to durability deterioration and achieves low-temperature fixability.

  Furthermore, an object of the present invention is to provide a process cartridge that suppresses fogging due to durability deterioration and achieves low-temperature fixability.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors have synthesized toners having an unevenness and have a molecular weight of 45,000 or more by gel permeation chromatography (GPC) measurement of toluene-soluble components. By controlling the toner to have at least one main peak in the region of 100000 or less, and to distribute the low molecular weight component more than the high molecular weight component than the peak molecular weight in the half width of the main peak. The present inventors have found that the fastness can be increased moderately and that both the fogging suppression and the low-temperature fixability associated with the deterioration of durability are satisfactorily combined.

  That is, the present invention is as follows.

It contains at least a colorant, a binder resin, and a release agent, has a volume average particle size of 4 to 10 μm, a shape factor SF-1 of 115 to 140, and an average circularity of 0.950 to 0.990. In a GPC chart having a BET specific surface area of 2.0 to 7.0 m ² / g and gel permeation chromatography (GPC) measurement of a toluene-soluble component, the horizontal axis is a logarithm of molecular weight. It has at least one peak in the region of 100,000 or less, draws a line horizontally with the base line at half the height of the main peak, and sets the linear length of the lower molecular weight component than the main peak molecular weight (Mp) to La, Mp When the linear length of the higher molecular weight component is Lb, the following relational expression (1) is established, and in the molecular weight integrated value in the region having a molecular weight of 3000 or more, the integrated value of the lower molecular weight component than Mp is the higher molecular weight component than Sa and Mp. Product of Following equation (2) holds the value when the Sb, a toner, wherein the toluene-insoluble matter is 45% or less.
La / Lb> 1 Relational expression (1)
Sa / Sb> 1 Relational expression (2)
Furthermore, the present invention is an image forming method based on a non-magnetic one-component developing method, and the image forming method regulates a toner layer on the toner carrier by bringing a toner regulating member into contact with the surface of the toner carrier. Toner layer forming step; the toner layer carried on the surface of the toner carrier is brought into contact with the surface of the electrostatic latent image carrier, whereby the electrostatic latent image is developed and the toner image is formed on the electrostatic latent image carrier. a developing step of forming a; having at least, the toner regulating member is 9.5 N / mm ² or more 100 N / mm ² less than universal hardness, the toner is at least a colorant, a binder resin and the release The volume average diameter is 4 to 10 μm, the shape factor SF-1 is 115 to 140, the average circularity is 0.950 to 0.990, and the specific surface area is 2.0 to 7.0 (m ² / g). Yes, with GPC measurement of toluene soluble components, with the horizontal axis representing the logarithm of molecular weight In the chart, it has at least one peak in the region of molecular weight 45000 or more and less than 100,000, and draws a line horizontally with the base line at half height of the main peak, and the linear length of the lower molecular weight component than the main peak molecular weight (Mp) The following relational expression (1) holds when the linear length of the high molecular weight component is Lb from the thickness La and Mp, and the integral value of the low molecular weight component below the Mp is Sa, The present invention relates to an image forming method characterized in that the following relational expression (2) holds when the integral value of the high molecular weight component is Sb from Mp, and the toluene insoluble content is 45% or less.
La / Lb> 1 Relational expression (1)
Sa / Sb> 1 Relational expression (2)
Furthermore, the present invention relates to a process cartridge used for forming an image by a non-magnetic one-component developing method, wherein the process cartridge is brought into contact with a toner storage portion, a toner carrier, and the toner carrier. At least a toner regulating member for regulating toner on the carrier and an electrostatic latent image carrier, and the electrostatic latent image carrier is brought into contact with the toner carrier to thereby form an electrostatic latent image. are arranged to development, the toner regulating member is 9.5 N / mm ² or more 100 N / mm ² less than universal hardness, the toner is at least a colorant, a binder resin and the release agent Containing, the volume average diameter is 4 to 10 μm, the shape factor SF-1 is 115 to 140, the average circularity is 0.950 to 0.990, the specific surface area is 2.0 to 7.0 (m ² / g), In GPC measurement of toluene-soluble components, the horizontal axis represents the molecular weight In the displayed GPC chart, it has at least one peak in the region of molecular weight 45000 or more and less than 100,000, and draws a line horizontally with the base line at half the height of the main peak, which is lower than the main peak molecular weight (Mp) When the linear length of the component is La and the linear length of the high molecular weight component is Lb from Mp, the following relational expression (1) holds. When the integral value of the high molecular weight component is Sb from the values Sa and Mp, the following relational expression (2) is established, and the process cartridge is characterized by having a toluene insoluble content of 45% or less.
La / Lb> 1 Relational expression (1)
Sa / Sb> 1 Relational expression (2)

  As described above, according to the present invention, it is possible to provide a toner, an image forming method, and a process cartridge that suppress fogging due to durability deterioration and achieve low-temperature fixability.

  In an image forming apparatus using a non-magnetic one-component development system, as described above, when durability evaluation is performed using a conventional emulsion aggregation toner, the image quality at the initial stage is achieved while achieving low-temperature fixability. It was difficult to hold.

The toner of the present invention contains at least a colorant, a binder resin, and a release agent, has a volume average particle size of 4 to 10 μm, a shape factor SF-1 of 115 to 140, and an average circularity of 0.1. 950 to 0.990, BET specific surface area is 2.0 to 7.0 m ² / g, and the horizontal axis represents logarithm of molecular weight in gel permeation chromatography (GPC) measurement of toluene soluble components. In the GPC chart, it has at least one peak in the region of molecular weight 45000 or more and 100000 or less, draws a line horizontally with the base line at half height of the main peak, and is a straight line of lower molecular weight component than the main peak molecular weight (Mp) When the length is La and the linear length of the high molecular weight component is Lb from Mp, the following relational expression (1) is established, and the integrated value of the low molecular weight component from Mp is Sa in the molecular weight integrated value in the region of molecular weight 3000 or more. Mp Following equation (2) holds the integral value of the high molecular weight component is taken as Sb, and wherein the toluene insoluble content is a toner 45% or less.
La / Lb> 1 Relational expression (1)
Sa / Sb> 1 Relational expression (2)
By satisfying the above physical property values, a sufficient fixing area can be ensured by the effect of molecular weight distribution and gel content, and the toner can be solidified by precise control effect of molecular weight distribution, and mechanical stress on the toner such as contact development is severe. Even on the machine, the fog caused by the deterioration could be suppressed.

  This is because the low-temperature fixability and durability of the optimal molecular weight in balance are controlled to the main peak, and the fragility inherent in the structure of the agglomerated toner is reduced on the low molecular weight side in the half-value width of the main peak. It is presumed that the result is suppressed by distributing a large abundance ratio and improving the binding property between primary aggregated particles having an approximate molecular weight.

The toner shape of the present invention has a volume average particle size of 4 to 10 μm, a shape factor SF-1 of 115 to 140, an average circularity of 0.950 to 0.990, and a BET specific surface area of 2. 0 to 7.0 m ² / g.

  As a method for obtaining a toner having such a shape, a conventionally known emulsion aggregation method is preferably used.

  A toner having a volume average particle size of less than 4 μm has a significantly high triboelectric charge amount, and therefore has poor transferability and cleaning properties.

  On the other hand, toner exceeding 10 μm has poor dot reproducibility and is not suitable for high-definition machines.

  When the toner has a shape factor SF-1 of less than 115, the transfer residue is difficult to clean, particularly when used in a low-temperature and low-humidity environment, and the image quality deteriorates.

  Toners having a shape factor SF-1 exceeding 140 are likely to break down due to endurance stress in aggregation toners, resulting in fogging deterioration due to an increase in deteriorated toner, contamination of the latent image carrier, charging member, etc. Causes degradation of image quality.

  A toner having an average circularity of less than 0.950 is vulnerable to endurance stress and cannot withstand long-term use for the same reason as described above.

  A toner having an average circularity exceeding 0.990 is disadvantageous for cleaning properties, and a toner having a BET specific surface area of less than 2.0, which is not suitable for high-quality image stability, is inherently advantageous for aggregating toners. A toner that cannot effectively exhibit the advantage and exceeds 7.0 has poor durability for the same reason as described above.

  For the measurement of the average particle diameter of the toner, for example, a Coulter Counter TA-II type or Coulter Multisizer (manufactured by Coulter Co., Ltd.) is used, and an interface (manufactured by Nikkiki) that outputs the number distribution and volume distribution is connected to a personal computer. It can be measured with the measuring device. In this measurement, an electrolytic solution is used. As this electrolytic solution, for example, a 1% NaCl aqueous solution prepared using primary sodium chloride or ISOTON R-II (manufactured by Coulter Scientific Japan) can be used.

  As a measurement method, 0.1 to 5 ml of a surfactant (preferably alkylbenzene sulfonate) is added as a dispersant to 100 to 150 ml of the electrolytic aqueous solution, and 2 to 20 mg of a measurement sample is further added. The electrolyte in which the sample is suspended is dispersed for about 1 to 3 minutes with an ultrasonic disperser, and the volume of the toner is measured by measuring the volume of toner of 2 μm or more with the Coulter Counter TA-II type using a 100 μm aperture as the aperture. Calculate the distribution. Then, the volume average particle diameter obtained from the volume distribution according to the present invention is obtained.

The shape factor SF-1 is measured by using a Hitachi FE-SEM (S-800) to randomly sample 100 toner images, and the image information is sent to a Nicole image analyzer (Luxex 3) via an interface. Introduced and analyzed, the arithmetic mean value of the values calculated from the following equation is defined.
SF-1 = {(MXLNG) ² / AREA} × (π / 4) × 100
(MXLNG: absolute maximum length, AREA: toner projected area)
The average circularity is measured by a toner-based diameter equivalent circle-circularity scattergram measured by a flow type particle image measuring apparatus. In the present invention, “FPIA-1000” (Toa Medical) is used. Measurement is performed using an electronic company), and an arithmetic average value of values (circularity) calculated using the following equation is used.
Circularity = circumferential length having the same projection area as the particle image / peripheral length of the particle projection image Here, the “particle projection area” is an area of the binarized toner particle image.

  As a specific measurement method, 10 ml of ion-exchanged water from which impure solids and the like are previously removed is prepared in a container, and a surfactant, preferably an alkylbenzene sulfonate, is added as a dispersant therein, and then further measurement is performed. Add 0.02 g of sample and disperse uniformly. As a means for dispersion, an ultrasonic disperser “UH-50 type” (manufactured by SMT Co., Ltd.) equipped with a 5Φ titanium alloy chip as a vibrator is subjected to a dispersion treatment for 5 minutes, and a measurement dispersion liquid and To do. In that case, it cools suitably so that the temperature of this dispersion may not be 40 degreeC or more.

  To measure the shape of the toner, the flow type particle image measuring device is used, the concentration of the dispersion is readjusted so that the toner particle concentration at the time of measurement is 3000 to 10,000 / μl, and 1000 or more toner particles are obtained. measure. After the measurement, the average circularity of the toner is obtained using this data.

  The measurement of the BET specific surface area is performed using a known apparatus such as a degassing apparatus Bacuprep 061 (manufactured by Micromesotic), a BET measuring apparatus Gemini 2375 (manufactured by Micromesotic). The BET specific surface area in the present invention is a value of a multipoint BET specific surface area. Specifically, the procedure is as follows.

  After measuring the weight of the empty sample cell, the sample to be measured is filled so as to fall between 0.01 and 0.002 g. Furthermore, the sample cell filled with the sample is set in the degassing apparatus, and degassing is performed at room temperature for 3 hours. After completion of degassing, the mass of the entire sample cell is measured, and the accurate mass of the sample is calculated from the difference from the empty sample cell. Next, empty sample cells are set in the balance port and analysis port of the BET measuring apparatus. Set a dewar with liquid nitrogen in place and measure P0 using the saturated vapor pressure (P0) measurement command. After the P0 measurement is completed, the sample cell prepared for degassing is set in the analysis port, the sample mass and P0 are input, and the measurement is started by the BET measurement command. After that, the BET specific surface area is automatically calculated.

  The resin composition in the toner of the present invention has a toluene insoluble content of 45% or less.

  The toluene-insoluble component in the present invention refers to a polymerization ratio of a polymer component (substantially crosslinked polymer) that has become insoluble in the toluene solvent in the resin composition in the toner. It can be used as a parameter indicating the degree of crosslinking. Toluene insoluble content is defined by the values measured as follows.

  A toner sample or a resin composition (0.5 to 1.0 g) is weighed (W1 g), put into a cylindrical filter paper (for example, No. 86R manufactured by Toyo Roshi), passed through a Soxhlet extractor, and 100 to 200 ml of toluene as a solvent. After extracting for a time and evaporating the soluble component extracted with the solvent, it is vacuum-dried at 40 ° C. for several hours, and the amount of the toluene-soluble resin component is weighed (W2 g). The weight of components other than the resin component such as pigment in the toner is defined as (W3 g). The toluene insoluble matter is obtained from the following formula.

トルエン不溶分が４5重量％を超えて含有すると、良好に低温定着化を達成することが困難である。低温定着性を保証しつつ、トルエン不溶分を４５重量％以下の範囲で適度に調整することで、定着可能温度領域を好適に拡大できる。

If the toluene insoluble content exceeds 45% by weight, it is difficult to achieve good low-temperature fixing. By appropriately adjusting the toluene insoluble content within a range of 45% by weight or less while ensuring low temperature fixability, the fixable temperature range can be suitably expanded.

The binder resin component of the toner of the present invention has at least one main peak in the region of molecular weight 45,000 to 100,000 in the molecular weight distribution of gel permeation chromatography (GPC) measured by toluene soluble content. When a line is drawn horizontally with the base line at a height of ½, the linear length of the low molecular weight component from the main peak molecular weight (Mp) is La, and the linear length of the high molecular weight component from Mp is Lb. Equation (1) holds, and in the molecular weight integral value in the region of molecular weight of 3000 or more, when the integral value of the low molecular weight component from Mp is Sa and the integral value of the high molecular weight component from Mp is Sb, the following relational expression (2) is obtained. It holds.
La / Lb> 1 Relational expression (1)
Sa / Sb> 1 Relational expression (2)
As a result of the inventors trying to synthesize the toner by controlling the main peak to 45,000 to 100,000 by a conventionally known emulsion aggregation method, the ratio of the high molecular weight component is inevitably distributed in the half-value width of the main peak. The value of Lb was less than 1.

  When these toners were continuously printed using a one-component contact developing device, good low-temperature fixability was achieved when 5 parts or more of the release agent component was included. Under the environment, the fog tends to deteriorate with the number of durable sheets. When the present inventors investigated the cause of the fog deterioration, it can be inferred that the exposure and increase in the amount of the release agent on the toner surface due to the progress of the toner destruction was due to the inhibition of the frictional power of the toner. It was.

  As a result of intensive studies to overcome the brittleness of the agglomeration method toner while controlling the main peak that can guarantee low-temperature fixability to 45,000 to 100,000, the present inventors have found that the approximate molecular weight components of the main peak are excellent. As a method of binding, by increasing the distribution of low molecular weight components in the half width of the main peak, it is possible to bind better in the step of welding the primary particles to each other, and the low melting point release agent Even in the agglomeration method toner containing a large amount of toner, the toner of the present invention, which is robust and advantageous for fogging, has been completed.

When La / Lb is 1 or less, it is difficult to suppress fogging in the latter half of the durability.
A more preferable range of La / Lb is 3.0> La / Lb> 1.1.

  When La / Lb is less than 1.1, the fog suppression effect is not remarkably exhibited.

  On the other hand, when La / Lb is larger than 3.0, the ratio of the low molecular weight component increases, so that the brittleness of the resin increases, and as a result, the fog in the latter half of the durability deteriorates.

  For the same reason as described above, the brittleness of the aggregation toner can be improved by satisfying the relationship of Sa / Sb> 1.

  A more preferable range of Sa / Sb is 6.0> Sa / Sb> 1.1.

  When Sa / Sb is less than 1.1, the fog suppression effect is not exhibited remarkably.

  On the other hand, when Sa / Sb is larger than 6.0, the ratio of the low molecular weight component increases, so that the brittleness of the resin increases, and as a result, the fog in the latter half of the durability deteriorates.

  As a method of controlling the molecular weight distribution to La / Lb> 1 and Sa / Sb> 1, it can be adjusted by a method of adding a chain transfer agent in several times when the binder resin is polymerized by emulsion polymerization. .

  In the present invention, the molecular weight distribution of the binder resin component is measured by GPC (gel permeation chromatography) under the following conditions.

First, as a sample preparation, 1 g of toner and 200 ml of toluene were precisely weighed, and reflux extraction was performed for 12 hours using a Soxhlet extractor. After the predetermined time, the filtrate was concentrated under reduced pressure using a rotary evaporator to obtain a toluene usable component of toner. This toluene-usable component was dissolved in tetrahydrofuran (THF) at room temperature so as to be 0.4 to 0.6 mg / ml, and the obtained solution was filtered through a solvent-resistant membrane filter having a pore diameter of 0.2 μm.
<GPC measurement conditions for toluene-soluble component of resin component>
Apparatus: GPC-150C (manufactured by Waters)
Column: 7 series of KF801-7 (manufactured by Shodex) Temperature: 40 ° C
Solvent: THF
Flow rate: 1.0 ml / min.
Sample: 0.1 ml of a sample having a concentration of 0.4 to 0.6% by weight is measured under the above conditions, and a molecular weight calibration curve prepared from a monodisperse polystyrene standard sample is used in calculating the molecular weight of the sample.

  The binder resin component of the toner of the present invention has the above-described molecular weight distribution and gel content, and has a melt index value (hereinafter referred to as MI value) of 0.1 to 0.1 measured under the following conditions. By being 20, low-temperature fixability and the fog suppression effect in the latter half of the durability are guaranteed.

  When the MI value is less than 0.1, the low-temperature fixability is inferior, and such a toner is liable to cause breakage of resin fine particles forming the toner in the latter half of the endurance, resulting in deterioration of fog.

  When the MI value exceeds 20, the layer thickness regulating member, the charging roller, the charging auxiliary roller, the electrostatic latent image carrier and the like are likely to be fused with durability, and there is a high risk of causing fatal image defects. Further, the amount of the surface release of the release agent component increases and the fog tends to deteriorate.

  Other components for further improving the effects of the present invention will be described below.

  First, a toner manufacturing method will be described.

  As a method for producing a toner base of the present invention, for example, a pH adjuster, a flocculant, a stabilizer, and the like are added to an aqueous dispersion containing polymer fine particles, colorant fine particles, and release agent fine particles, and a large number of the fine particles are aggregated. What is obtained by thermally fusing the agglomerated particles is most preferable.

  In this toner manufacturing method, in the aggregation step, resin particles, colorant particles, or release agent fine particles that are uniformly dispersed in the mixed solution are aggregated to form aggregated particles. In the thermal fusing step, the resin in the aggregated particles is melted and fused to form toner particles.

  Hereinafter, the method for producing the toner of the present invention will be described in detail.

  The resin particle dispersion is obtained by dispersing at least resin particles in a dispersant. Examples of the resin include thermoplastic binder resins. Specifically, homopolymers or copolymers (styrene-based resins) of styrenes such as styrene, parachlorostyrene, and α-methylstyrene; acrylic Methyl acid, ethyl acrylate, n-propyl acrylate, n-butyl acrylate, lauryl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, lauryl methacrylate, methacrylic acid 2 -Homopolymers or copolymers of vinyl group esters such as ethylhexyl (vinyl resins); Homopolymers or copolymers of vinyl nitriles such as acrylonitrile and methacrylonitrile (vinyl resins); A single vinyl ether such as ether or vinyl isobutyl ether Polymer or copolymer (vinyl resin); homopolymer or copolymer of vinyl ketones such as vinyl methyl ketone, vinyl ethyl ketone, vinyl isopropenyl ketone (vinyl resin); ethylene, propylene, butadiene, isoprene, etc. Homopolymers or copolymers of olefins (olefin resins); non-vinyl condensation resins such as epoxy resins, polyester resins, polyurethane resins, polyamide resins, cellulose resins, and polyether resins, and these non-vinyl condensation resins And a graft polymer of a vinyl monomer and the like. These resins may be used alone or in combination of two or more.

  Among these resins, vinyl resins are particularly preferable. In the case of a vinyl resin, it is advantageous in that a resin particle dispersion can be easily prepared by emulsion polymerization or seed polymerization using an ionic surfactant or the like. Examples of the vinyl monomer include acrylic acid, methacrylic acid, maleic acid, cinnamic acid, fumaric acid, vinyl sulfonic acid, ethylene imine, vinyl pyridine, vinyl amine, and other vinyl polymer acids and vinyl polymer bases. The monomer used as a raw material is mentioned. In the present invention, the resin particles preferably contain the vinyl monomer as a monomer component, and a styrene-acrylic resin with a small change in toner charge amount in a high temperature and high humidity or low temperature and low humidity environment is preferable. In the present invention, among these vinyl monomers, vinyl polymer acids are more preferable from the viewpoint of ease of formation reaction of vinyl resins, and specifically, acrylic acid, methacrylic acid, maleic acid, cinnamon. A dissociable vinyl monomer having a carboxyl group such as an acid or fumaric acid as a dissociating group is particularly preferred from the viewpoint of controlling the degree of polymerization and the glass transition point. Furthermore, at this time, in order to adjust the molecular weight, a chain transfer agent, a crosslinking agent, or the like can be used in combination.

  For example, the chain transfer agent is not particularly limited, and for example, mercaptans such as octyl mercaptan, dodecyl mercaptan, tert-dodecyl mercaptan, halogen compounds such as carbon tetrabromide, disulfides and the like are used.

  Furthermore, as the crosslinking agent, those having two or more unsaturated bonds such as divinylbenzene, divinylnaphthalene, divinyl ether, diethylene glycol methacrylate, ethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, hexanediol diacrylate, diallyl phthalate, etc. In particular, divinylbenzene is preferably used.

  In the present invention, the radical polymerization initiator can be appropriately used as long as it is water-soluble. For example, persulfates (potassium persulfate, ammonium persulfate, etc.), azo compounds [4,4′-azobis-4-cyanovaleric acid and its salts, 2,2′-azobis (2-amidinopropane) salts, etc.], Examples thereof include peroxide compounds such as hydrogen oxide and benzoyl peroxide.

  Furthermore, the radical polymerization initiator can be combined with a reducing agent as necessary to form a redox initiator. By using a redox initiator, the polymerization activity is increased, the polymerization temperature can be lowered, and the polymerization time can be further shortened.

  Any temperature may be selected as long as the polymerization temperature is equal to or higher than the lowest radical generation temperature of the polymerization initiator, but a range of 50 ° C. to 80 ° C., for example, is used under normal pressure. Further, polymerization can be performed at a temperature equal to or higher than the boiling point of the dispersion (usually an aqueous medium) under pressurized conditions.

  Surfactants that can be used for polymerization include sulfonates (sodium dodecylbenzenesulfonate, sodium arylalkylpolyethersulfonate, 3,3-disulfonediphenylurea-4,4-diazo-bis-amino-8- Sodium naphthol-6-sulfonate, ortho-carboxybenzene-azo-dimethylaniline, 2,2,5,5-tetramethyl-triphenylmethane-4,4-diazo-bis-β-naphthol-6-sulfonate Sulfate ester salts (sodium dodecyl sulfate, sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate, etc.), fatty acid salts (sodium oleate, sodium laurate, sodium caprate, sodium caprylate, sodium caproate) , Potassium stearate, calcium oleate), and the like.

  As an average particle diameter of the said resin particle, it is 1 micrometer or less normally, and it is preferable that it is 0.01-1 micrometer. When the average particle size exceeds 1 μm, the particle size distribution of the finally obtained toner is broadened or free particles are generated, which tends to cause a decrease in performance and reliability. On the other hand, when the average particle size is within the above range, there are no disadvantages, and the uneven distribution among the toners is reduced, the dispersion in the toners is improved, and the variation in performance and reliability is advantageous.

The colorant particle dispersion is obtained by dispersing at least colorant particles in a dispersant. Examples of the colorant include phthalocyanine pigments, monoazo pigments, bisazo pigments, magnetic powder, and quinacridone pigments. Specific examples thereof include, for example, carbon black, chrome yellow, hansa yellow, benzidine yellow, sren yellow, quinoline yellow, permanent orange GTR, pyrazolone orange, vulcan orange, watch young red, permanent red, brillianthamine 3B, brillianthamine. 6B, DuPont Oil Red, Pyrazolone Red, Resol Red, Rhodamine B Lake, Lake Red C, Rose Bengal, Aniline Blue, Ultramarine Blue, Calco Oil Blue, Methylene Blue Chloride, Phthalocyanine Blue, Phthalocyanine Green, Malachite Green Oxalate, etc. Various pigments: acridine, xanthene, azo, benzoquinone, azine, anthraquinone, dioxane Various dyes such as gin, thiazine, azomethine, indico, thioindico, phthalocyanine, aniline black, polymethine, triphenylmethane, diphenylmethane, thiazine, thiazole and xanthene; . These colorants may be used alone or in combination of two or more.

  The average particle diameter of the colorant particles is preferably 0.5 μm or less, and more preferably 0.2 μm or less. If the average particle diameter exceeds 0.5 μm, irregular reflection of visible light cannot be prevented, and if coarse particles are present, coloring power, color reproducibility, and OHP permeability are adversely affected, and agglomerated particles described below. In the forming step, the resin particles and the colorant particles do not aggregate, or even if they aggregate, they may be detached at the time of fusion, which is not preferable in that the quality of the obtained toner may deteriorate. On the other hand, when the average particle size is within the above range, there are no disadvantages, and the uneven distribution among the toners is reduced, the dispersion in the toner is good, and the variation in performance and reliability is advantageous. .

  The release agent particle dispersion is obtained by dispersing at least release agent particles in a dispersant.

  As the mold release agent, those having a maximum endothermic peak of 150 ° C. or less are used, and those having a maximum endotherm of 45 ° C. to 130 ° C. can preferably achieve both durability and mold release properties.

  For example, low molecular weight polyolefins such as polyethylene; silicones having a melting point (softening point) upon heating; fatty acid amides such as oleic acid amide, erucic acid amide, ricinoleic acid amide, and stearic acid amide; ester waxes such as stearyl stearate Plant waxes such as carnauba wax, rice wax, candelilla wax, tree wax, jojoba oil; animal waxes such as beeswax; montan wax, ozokerite, ceresin, paraffin wax, microcrystalline wax, Fischer-Tropsch wax, etc. And particles such as mineral / petroleum wax; and modified products thereof. Among them, ester wax is preferably used from the viewpoints of stability when it is used as a release agent particle dispersion, environmental resistance when it is made into toner, image stability, and the like. In particular, esterified wax of pentaerythritol is used as a toner. The environmental stability and fixability are advantageous and more preferable.

  As an optimal wax that can achieve a good balance between low temperature fixability and durability by matching with the physical properties of the binder resin of the present invention, a low melting point ester wax having a maximum endothermic peak of 45 ° C. or higher and 70 ° C. or lower can be obtained. preferable.

  Further, in order to widen the latitude of the fixable temperature, in addition to the low melting point wax, a high melting point wax having a maximum endothermic peak of more than 70 ° C. and not more than 130 ° C. can be used to suitably impart a function.

  The average particle size of the release agent particles is preferably 2.0 μm or less, and more preferably 1.0 μm or less. When the average particle diameter exceeds 2.0 μm, the wax content tends to occur between the toners, which adversely affects the stability of the image over a long period of time. On the other hand, when the average particle size is within the above range, uneven distribution between toners is reduced, dispersion in the toner is improved, and variations in performance and reliability are reduced.

  There is no restriction | limiting in particular as a combination of the said colorant particle, the said resin particle, and the said mold release agent particle | grains, According to the objective, it can select suitably.

  In addition to the resin particle dispersion, the colorant particle dispersion, and the release agent dispersion, a particle dispersion obtained by dispersing appropriately selected particles in a dispersant may be further mixed.

  The particles contained in the particle dispersion are not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include internal additive particles, charge control agent particles, inorganic particles, and abrasive particles. In the present invention, these particles may be dispersed in the resin particle dispersion or the colorant particle dispersion.

  Examples of the charge control agent particles include particles such as quaternary ammonium salt compounds, nigrosine compounds, compounds composed of complexes of aluminum, iron, chromium, zinc, zirconium, and the like. The charge control agent particles in the present invention are preferably those that are difficult to dissolve in water from the viewpoints of controlling ionic strength that affects the stability during aggregation and fusion and recycling wastewater.

  The average particle size of the above-mentioned particles is usually 1 μm or less, and preferably 0.01 to 1 μm. When the average particle size exceeds 1 μm, the particle size distribution of the finally obtained toner is broadened or free particles are generated, which tends to cause a decrease in performance and reliability. On the other hand, when the average particle size is within the above range, there are no disadvantages, and the uneven distribution among the toners is reduced, the dispersion in the toners is improved, and the variation in performance and reliability is advantageous.

  Examples of the dispersant contained in the resin particle dispersion, the colorant particle dispersion, the release agent dispersion, the particle dispersion, and the like include an aqueous medium containing a polar surfactant. Examples of the aqueous medium include water such as distilled water and ion exchange water, and alcohols. These may be used individually by 1 type and may use 2 or more types together. The content of the polar surfactant in the dispersant having the polarity cannot be generally defined and can be appropriately selected according to the purpose.

  Examples of the polar surfactant include anionic surfactants such as sulfate ester, sulfonate, phosphate, and soap; cationic surfactants such as amine salt type and quaternary ammonium salt type Is mentioned. Specific examples of the anionic surfactant include sodium dodecylbenzenesulfonate, sodium dodecylsulfate, sodium alkylnaphthalenesulfonate, sodium dialkylsulfosuccinate and the like. Specific examples of the cationic surfactant include alkylbenzene dimethyl ammonium chloride, alkyl trimethyl ammonium chloride, distearyl ammonium chloride and the like. These may be used individually by 1 type and may use 2 or more types together.

  In the present invention, these polar surfactants and nonpolar surfactants can be used in combination. Examples of the nonpolar surfactant include nonionic surfactants such as polyethylene glycol, alkylphenol ethylene oxide adducts, and polyhydric alcohols.

  As content of the said resin particle in the said resin particle dispersion liquid, it is 5-60 mass parts normally, Preferably it is 10-40 mass parts. Further, the content of the resin particles in the aggregated particle dispersion when the aggregated particles are formed may be 50 parts by mass or less, and is preferably about 2 to 40 parts by mass.

  The content of the colorant particles and the like is about 1 to 10 parts by mass and preferably about 2 to 6 parts by mass in the aggregated particle dispersion when the aggregated particles are formed.

  The content of the release agent particles and the like is about 1 to 25 parts by mass and preferably about 5 to 20 parts by mass in the aggregated particle dispersion when the aggregated particles are formed. When the content is less than 5 parts by mass, a sufficient release effect cannot be obtained and the low-temperature fixability is poor.

  On the other hand, if the content of the release agent exceeds 20 parts by mass, the amount of the existing surface of the release agent or the amount of precipitation increases with the endurance deterioration of the toner, so that the fog characteristics deteriorate.

  On the other hand, when the content is larger than 20 parts by mass, the particle size distribution may be broadened depending on the type of the release agent, and the characteristics may be deteriorated. In this case, for example, when the resin particles are produced, the above problem can be solved by performing seed polymerization on the release agent.

  Furthermore, in order to control the chargeability of the toner obtained, the charge control particles and the resin particles may be added after the aggregated particles are formed.

(Dispersion preparation process)
The resin particle dispersion is prepared, for example, as follows. That is, the resin in the resin particles is a homopolymer or copolymer (vinyl resin) of a vinyl monomer such as the ester having a vinyl group, the vinyl nitrile, the vinyl ether, or the vinyl ketone. In some cases, a vinyl monomer homopolymer or copolymer (vinyl resin) resin is obtained by emulsion polymerization or seed polymerization of the vinyl monomer in an ionic surfactant. A dispersion is prepared by dispersing particles in an ionic surfactant. When the resin in the resin particles is a resin other than a homopolymer or copolymer of the vinyl monomer, the resin can be dissolved in an oily solvent having a relatively low solubility in water. The resin is dissolved in the oily solvent, and the solution is finely dispersed in water together with an ionic surfactant and a polymer electrolyte using a disperser such as a homogenizer, and then heated or decompressed to remove the oily solvent. By transpiration, a dispersion liquid in which resin particles made of resin other than vinyl resin are dispersed in an ionic surfactant is prepared.

  The dispersion means is not particularly limited, and examples thereof include known dispersion apparatuses such as a rotary shear type homogenizer and a ball mill having a medium, a sand mill, and a dyno mill.

  The colorant particle dispersion liquid, the release agent dispersion liquid, the particle dispersion liquid, and the like are prepared, for example, by adding particles such as the colorant particles to a dispersant and dispersing the particles using the dispersion means. Is done.

  The particle size of the colorant particle dispersion, the release agent dispersion, the particle dispersion and the like was measured using a laser diffraction / scattering particle size distribution analyzer LA-920 manufactured by Horiba.

(Aggregation process)
In the aggregated particle formation, aggregated particles are formed in the mixed solution to prepare an aggregated particle dispersion. The agglomerated particles can be formed in the mixed solution by adding, for example, a pH adjusting agent, a flocculant, and a stabilizer to the mixed solution and mixing them, and appropriately adding temperature, mechanical power and the like.

  Examples of the pH adjuster include alkalis such as ammonia and sodium hydroxide, and acids such as nitric acid and citric acid. Examples of the flocculant include monovalent metal salts such as sodium and potassium; divalent metal salts such as calcium and magnesium; trivalent metal salts such as iron and aluminum; and alcohols such as methanol, ethanol and propanol. It is done.

  Examples of the stabilizer mainly include the polar surfactant itself or an aqueous medium containing the same. For example, when the polar surfactant contained in the aqueous dispersion is anionic, a cationic one can be selected as the stabilizer.

  The addition / mixing of the flocculant and the like is preferably performed at a temperature below the glass transition point of the resin contained in the mixed solution. When the mixing is performed under this temperature condition, aggregation proceeds in a stable state. The mixing can be performed using, for example, a known mixing device, a homogenizer, a mixer and the like.

  The average particle size of the aggregated particles formed here is not particularly limited, but is usually controlled to be about the same as the average particle size of the toner to be obtained. The control can be easily performed, for example, by appropriately setting and changing the temperature and the stirring and mixing conditions. Through the above-described aggregated particle forming step, aggregated particles having an average particle size substantially the same as the average particle size of the toner are formed, and an aggregated particle dispersion liquid in which the aggregated particles are dispersed is prepared.

(Heat fusion process)
The thermal fusion process is a process in which the aggregated particles are heated and fused. Before entering the fusing step, the pH adjusting agent, the polar surfactant, the nonpolar surfactant, and the like can be appropriately added in order to prevent fusing between toner particles.

  The heating temperature may be from the glass transition temperature of the resin contained in the aggregated particles to the decomposition temperature of the resin. Therefore, the temperature of the heating differs depending on the type of resin of the resin particles and the resin fine particles, and cannot be generally defined. However, in general, the glass of resin contained in the aggregated particles or the adhered particles Transition point temperature to 140 ° C. In addition, the said heating can be performed using a publicly known heating apparatus and instrument.

  As the fusion time, a short time is sufficient if the heating temperature is high, and a long time is required if the heating temperature is low. That is, the fusion time depends on the temperature of the heating and cannot be defined in general, but is generally 30 minutes to 10 hours.

(Washing / drying process)
In the present invention, the toner obtained after the end of the fusing process can be washed, dried, etc. under appropriate conditions. In addition, inorganic particles such as silica, alumina, titania, calcium carbonate, and resin particles such as vinyl resin, polyester resin, and silicone resin are added to the surface of the obtained toner by applying a shearing force in a dry state. May be. These inorganic particles and resin particles function as external additives such as fluidity aids and cleaning aids.

(External addition process)
In the present invention, various fine powders generally known as external additives can be added to the toner particle surfaces as necessary.

  As the external additive used in the present invention, known inorganic fine powders or resin particles are used. In order to improve charging stability, developability, fluidity, and storage stability, silica, alumina, titania or a double oxide thereof may be used. It is preferably selected from inorganic fine powders.

  In addition, the external additive used in the present invention has a silicone varnish, various modified silicone varnishes, silicone oil, various modified silicone oils, a silane coupling agent, and a functional group as necessary for the purpose of hydrophobization and chargeability control. It can also be treated with a treating agent such as a silane coupling agent, an organic silicon compound, or an organic titanium compound, or in combination with various treating agents.

  For example, silane coupling agents typically include dimethyldichlorosilane, trimethylchlorosilane, allyldimethylchlorosilane, hexamethyldisilazane, allylphenyldichlorosilane, benzyldimethylchlorosilane, vinyltriethoxysilane, γ -Methacryloxypropyltrimethoxysilane, vinyltriacetoxysilane, divinylchlorosilane, dimethylvinylchlorosilane and the like. The inorganic fine powder is treated with a silane coupling agent by dry treatment in which the vaporized silane coupling agent is reacted with a cloud of inorganic fine powder by stirring or the like, or a silane cup in which the inorganic fine powder is dispersed in a solvent. It can be processed by a generally known apparatus such as a wet method in which a ring agent is dropped.

  As the external addition method, a conventionally known method such as a Henschel mixer can be used.

  As a method for obtaining the toner of the present invention, there is a method in which the step of preparing the resin fine particle dispersion is suitable in the aggregation method. Specifically, in the initial stage of emulsion polymerization or solution polymerization, the reaction temperature is adjusted; the pressure during the reaction is adjusted; a plurality of methods such as an initiator and a chain transfer agent are used; And the like.

  Further, the toner of the present invention can be suitably obtained also by a method such as adding a chain transfer agent when seed polymerization is performed in the heat fusion step.

  Next, an image forming method of the present invention, an image forming apparatus that implements the method, and a process cartridge will be described with reference to the drawings.

  First, the toner layer regulating member will be described with reference to FIG.

  In FIG. 1, reference numeral 5 denotes a toner container for storing a non-magnetic toner 4 as a one-component developer, and an electrostatic latent image carrier is provided in an opening extending in the longitudinal direction in the toner container 5. A developing roller 2 as a toner carrying member disposed to face the photosensitive drum 1 is rotatably disposed. In addition, the developing roller 2 is provided horizontally at the opening of the toner container 5 such that the right half circumferential surface shown in the drawing enters the toner container 5 and the left half circumferential surface is exposed outside the toner container 5.

  The regulating blade 3 as a toner regulating member is provided above the developing roller 2 by being supported by a presser metal plate 6, and the vicinity of the free end side of the regulating blade 3 is in surface contact with the outer peripheral surface of the developing roller 2. It is in contact with the state. The contact direction of the regulating blade 3 with respect to the developing roller 2 is a so-called counter (reverse) direction in which the tip end side is located upstream of the rotation direction of the developing roller 2 with respect to the contact portion.

  In the present invention, by setting the universal hardness of the toner layer regulating member within a suitable range, the mechanical stress applied to the toner can be reduced, and the toner can be imparted with good charge. The effect of suppressing is further improved.

  Here, the universal hardness in the present invention is measured based on the following measuring method.

(Universal hardness measurement method)
Measurement is performed using a hardness scale Fischer scope H100 manufactured by Fischer, Germany. This device uses a diamond indenter with a shape of a quadrangular pyramid and a face-to-face angle of 136 °, and when the set load is pushed into the target stepwise, the indentation search with the load applied is performed. Is detected and read electrically. The hardness value H is expressed as a ratio obtained by dividing the test load by the surface area of the indentation generated by the test load. The universal hardness value HU is represented by a hardness value at the set maximum indentation search.

  In the present invention, the measurement was performed by setting the set maximum pushing depth when measuring the universal hardness value HU to 15 μm.

  The reason why the universal hardness is an effective parameter in the present invention is not clear in detail, but is presumed as follows.

  The Fischer scope H100 is not a method of pushing the indenter into the surface of the test piece as in the conventional micro-Biccus method and measuring the residual indentation after unloading with a microscope to obtain the hardness. This is a measurement method that directly reads the indentation depth under load and obtains continuous hardness. Therefore, it is possible to measure the hardness of the thin film elastic body, which has been difficult to measure conventionally.

  Usually, as a method for measuring the hardness of an elastic body, it is widely known to use a Shore hardness tester or the like. However, the thickness of the test piece required in these measurement methods is several mm, which is thicker than the thickness of the toner layer regulating member actually used.

  On the other hand, the universal hardness obtained using the Fischer scope H100 can set the indentation depth in microns. The reason why the universal hardness is an effective parameter in the present invention is presumed to be that the surface hardness is measured in accordance with the actual usage pattern.

  The universal hardness of the restricting member is preferably 9.5 or more and less than 100. If it is less than 9.5 (soft), the toner particles are buried, the toner particles stay in the nip for a long time, and the fusion to the toner layer regulating member is promoted by the frictional heat accompanying the rotation of the developer carrier. Cause defects. On the other hand, when the universal hardness is 100 or more (hard), toner breakage and deformation are promoted at the nip portion and the durability cannot be endured.

  In the present invention, an elastic layer containing a nitrogen-containing compound is preferably provided on the surface layer of the toner layer regulating member. When the surface layer material is a nitrogen-containing compound, the charge imparting performance to the toner is more excellent, and therefore, the fog-suppressing power when the toner deteriorates in the latter half of the endurance is superior, which is preferable.

  Specific examples of the nitrogen-containing compound include polyurethane, polyamide, various nylons and the like. Among these, polyamide elastomers are excellent in moldability and charging characteristics and can be suitably used.

  As the toner carrying member, an elastic roller can be used, and a method can be used in which the surface of the elastic roller is coated with toner and brought into contact with the surface of the photosensitive member. In general, in a developing method in which a toner carrier and a photoreceptor are in contact with each other, toner is easily damaged or deformed. However, when the toner described in the present invention is used, such a change can be effectively suppressed. preferable.

In this case, development is performed by an electric field acting between the photosensitive member and the elastic roller facing the surface of the photosensitive member via the toner. Therefore, the surface of the elastic roller or the vicinity of the surface has a potential, and it is necessary to have an electric field in a narrow gap between the surface of the photosensitive member and the surface of the toner carrying member. For this reason, it is possible to use a method in which the elastic rubber of the elastic roller is resistance controlled to the middle resistance region to keep the electric field while preventing conduction with the surface of the photoreceptor, or a method of providing a thin insulating layer on the surface layer of the conductive roller. . Further, a conductive resin sleeve in which the side facing the surface of the photoreceptor is covered with an insulating material on the conductive roller, or a conductive layer is provided on the side not facing the photoreceptor with an insulating sleeve is also possible. . Further, a configuration in which a rigid roller is used as the toner carrying member and the photosensitive member is a flexible material such as a belt is possible. The resistance value of the roller as the toner carrier is preferably in the range of 10 ² to 10 ⁹ Ω · cm.

  As the surface shape of the toner carrier, when the surface roughness Ra (μm) is set to 0.2 to 3.0, both high image quality and high durability can be achieved. The surface roughness Ra correlates with the toner conveying ability and the toner charging ability. If the surface roughness Ra of the toner carrier exceeds 3.0, it is difficult not only to make the toner layer on the toner carrier thin, but also the chargeability of the toner is not improved, so that improvement in image quality cannot be expected. . Since the toner carrying ability on the surface of the toner carrier is suppressed by setting it to 3.0 or less, the toner layer on the toner carrier is thinned, and the number of contact between the toner carrier and the toner increases. Since the chargeability of the toner is also improved, the image quality is synergistically improved. On the other hand, when the surface roughness Ra is smaller than 0.2, it becomes difficult to control the toner coat amount.

  In the present invention, the surface roughness Ra of the toner carrier is based on JIS surface roughness “JIS B 0601 (2001)” using a surface roughness measuring device (“Surfcoder SE-30H” manufactured by Kosaka Laboratory Ltd.). Corresponds to the centerline average roughness measured. Specifically, a 2.5 mm portion as the measurement length a is extracted from the roughness curve in the direction of the center line, the center line of the extracted portion is the X axis, the direction of the vertical magnification is the Y axis, and the roughness curve is When expressed by y = f (x), it means a value obtained by the following formula expressed in micrometers (μm).

本発明の画像形成方法としては、トナー層規制部材により規制され、帯電付与されたトナーに対し、更にトナー担持体に接触した帯電補助ローラーによりバイアスを印加しても良い。これによりトナーの帯電が増すだけでなく均一化されることになりカブリ、ボタ落ちなどを含め、画質が向上するため望ましい。

In the image forming method of the present invention, a bias may be applied to the charged toner that is regulated by the toner layer regulating member and further in contact with the toner carrying member. This not only increases the charging of the toner but also makes it uniform, which is desirable because it improves the image quality including fogging and blurring.

As the auxiliary charging roller, a rubber or sponge material appropriately adjusted in resistance, such as chloroprene rubber, isoprene rubber, EPDM rubber, polyurethane rubber, epoxy rubber, butyl rubber, and silicone rubber, is preferably used. The rate is 10 ⁹ Ωcm or less, preferably 10 ⁴ Ωcm or more.

  In the image forming method of the present invention, the toner carrier may be rotated in the same direction as the circumferential speed of the photosensitive member, or may be rotated in the opposite direction. When the rotation is in the same direction, it is preferable to set the peripheral speed of the toner carrier to be 1.05 to 3.0 times the peripheral speed of the photosensitive member.

  When the peripheral speed of the toner carrier is less than 1.05 times the peripheral speed of the photoreceptor, the stirring effect received by the toner on the photoreceptor is insufficient, and good image quality cannot be expected. On the other hand, when the peripheral speed ratio exceeds 3.0, toner deterioration due to mechanical stress and toner adhesion to the toner carrier are generated and promoted, which is not preferable.

As the photosensitive member, a photosensitive drum or a photosensitive belt having a photoconductive insulating material layer such as a-Se, CdS, ZnO ₂ , OPC, or a-Si is preferably used. Further, the binder resin of the organic photosensitive layer in the OPC photoreceptor is not particularly limited. Of these, polycarbonate resins, polyester resins, and acrylic resins are particularly preferable because they are excellent in transferability and hardly cause toner fusion to the photoreceptor and filming of external additives.

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

  FIG. 2 is a schematic configuration diagram of an example of a process cartridge and a developing device for carrying out the image forming method of the present invention. In FIG. 2, reference numeral 10 denotes a primary charging member that contacts the photosensitive drum 1 and performs direct charging. 1 is a charging power source, 11 to 13 is a bias power source, 15 is a transfer material such as paper, 16 is a transfer member, 17 is a pressure roller for fixing, 18 is a heating roller for fixing, and 19 is a cleaner. Have the same symbols.

  A bias power supply 11 is connected to the charging roller 10 so as to uniformly charge the surface of the photosensitive drum 1. The developing device 7 contains the toner 4 in a toner container 5 and includes a developing roller 2 that is a toner carrier that rotates in the direction of the arrow. Further, the regulating blade 3 and the toner 4 which are toner regulating members for regulating the toner and charging are attached to the developing roller 2 and rotated in the direction of the arrow in order to apply the charging to the toner by friction with the developing roller 2. An application roller 9 is also provided. A developing bias power source 13 is connected to the developing roller 2. A bias power source (not shown) is also connected to the application roller 9, and when negatively charged toner is used, a voltage is applied to the negative side of the developing bias, and when positively charged toner is used, a voltage is applied to the positive side of the developing bias. Is set.

  A transfer bias power source 12 having a polarity opposite to that of the photosensitive drum 1 is connected to the transfer member 16.

  As the developing roller 2 which is a toner carrier, a so-called elastic roller having an elastic layer on the surface is preferably used. The hardness of the material of the elastic layer used for the elastic roller is preferably 30 to 60 degrees (asker-C / load 1 kg).

  The toner coat amount is controlled by a regulation blade 3, which is in contact with the developing roller 2 through a toner layer. The contact pressure between the regulating blade 3 and the developing roller 2 at this time is preferably in the range of 0.05 N / cm or more and 0.5 N / cm or less as the linear pressure in the direction of the developing roller 2 bus.

  Incidentally, the linear pressure is a load applied per length of the blade 3, for example, when a load of 1.2 N is applied to the blade 3 having a contact length of 1 m and brought into contact with the developing roller 2, The linear pressure is 1.2 N / m. If it is less than 0.05 N / cm, in addition to controlling the toner coating amount, uniform frictional charging becomes difficult, which may cause fogging. On the other hand, if it exceeds 0.5 N / cm, the toner particles are subjected to an excessive load, so that deformation of the particles and fusion of the toner to the regulating blade 3 or the developing roller 2 are liable to occur.

  The free end portion of the regulating blade 3 may have any shape, for example, in addition to a linear cross-sectional shape, an L-shape bent near the tip, a shape swelled in the vicinity of the tip, etc. Are preferably used.

  As the toner regulating member, a material in which a metal elastic body such as stainless steel, steel, phosphor bronze or the like is used as a base material and a resin is adhered or coated on a portion that contacts the sleeve contact portion is preferably used.

  Furthermore, by applying a DC electric field and / or an AC electric field to the toner regulating member, the uniform thin layer coating property and the uniform charging property are further improved due to the loosening action on the toner, and sufficient image density is achieved. A good quality image can be obtained.

  In FIG. 2, the photosensitive drum 1 rotating in the direction of the arrow is uniformly charged by the primary charging member. In this example, the primary charging member is a charging roller 10 that basically includes a central core 10b and a conductive elastic layer 10a that forms the outer periphery thereof. The charging roller 10 is brought into contact with one surface of the photosensitive drum 1 serving as an electrostatic latent image carrier with a suppressed pressure, and is driven to rotate as the photosensitive drum 1 rotates.

  As a preferable process condition when the charging roller 10 is used, the contact pressure of the roller is 0.05 to 5 N / cm, and the applied voltage is a DC voltage or a DC voltage superimposed with an AC voltage. Although not particularly limited, when a DC voltage superimposed with an AC voltage is used, the AC voltage is 0.5 to 5 dVpp, the AC frequency is 50 Hz to 5 kHz, and the DC voltage is ± 0.2 to ± 1.5 kV. When DC voltage is used, DC voltage = ± 0.2 to ± 5 kV. In the present invention, an applied voltage of only a DC voltage is preferably used.

  As charging means other than the charging roller 10, there are a method using a charging blade and a method using a conductive brush. These contact charging means have an effect that a high voltage is unnecessary and generation of ozone is reduced as compared with non-contact corona charging. The material of the charging roller and charging blade as the contact charging means is preferably conductive rubber, and a release coating may be provided on the surface thereof. As the releasable coating, nylon resin, PVDF (polyvinylidene fluoride), PVDC (polyvinylidene chloride), and the like are applicable.

  Following the electrostatic latent image carrier charging step, for example, an electrostatic latent image corresponding to an information signal is formed on the photosensitive drum 1 by exposure 14 from a light emitting element, and the toner is brought into contact with the developing roller 2 by a toner. The electrostatic latent image is developed and visualized. Furthermore, in the image forming method of the present invention, it is possible to develop faithfully with respect to the dot latent image so as not to disturb the latent image, particularly in combination with a developing system that forms a digital latent image on the photosensitive drum 1. It becomes. The visible image is transferred to the transfer material 15 by the transfer member 16 and is fixed by passing between the heating roller 18 and the pressure roller 17 to obtain a permanent image. The heating and pressure fixing means includes a heating roller 18 incorporating a heating element such as the halogen heater shown here and an elastic pressing roller 17 pressed against the heating roller 18 with a basic structure. In addition, a method of fixing by heating with a heater through a film is also used.

  On the other hand, the untransferred toner remaining on the photosensitive drum 1 without being transferred is collected by a cleaner 19 having a cleaning blade in contact with the surface of the photosensitive drum 1, and the photosensitive drum 1 is cleaned.

  FIG. 3 is a schematic configuration diagram of an example of an image forming apparatus that batch-transfers multiple toner images onto a recording material using an intermediate transfer member in the image forming method of the present invention.

  In FIG. 3, 7a to 7d are black, yellow, magenta and cyan developing devices, 21 is a light source device, 22 is a laser beam, 23 is a fixing device, 24 is a developing unit, and 25 is an intermediate transfer member. An intermediate transfer drum, 25a is a conductive support, 25b is an elastic layer, 26 is a bias power source, 27 is a transfer material tray, and 28 is a secondary transfer device. The same members as those in FIGS. did.

  A surface of the photosensitive drum 1 as an electrostatic latent image carrier is brought into contact with a rotatable charging roller 10 to which a charging bias voltage as a charging member is applied while rotating, so that the surface of the photosensitive drum 1 is uniformly primary. A first electrostatic latent image is formed on the photosensitive drum 1 by the laser beam 22 that is charged and emitted from the light source device 21 as an exposure unit. The formed first electrostatic latent image is developed with black toner in a black developing device 7a serving as a first developing device provided in the rotatable developing unit 24 to form a black toner image. The black toner image formed on the photosensitive drum 1 is electrostatically primarily transferred onto the intermediate transfer drum 25 by the action of a transfer bias voltage applied to the conductive support 25a of the intermediate transfer drum 25. Next, a second electrostatic latent image is formed on the surface of the photosensitive drum 1 in the same manner as described above, the developing unit 24 is rotated, and the yellow toner in the yellow developing device 7b as the second developing device is used. Development is performed to form a yellow toner image, and the yellow toner image is electrostatically primary transferred onto the intermediate transfer drum 25 on which the black toner image is primarily transferred. Similarly, the third electrostatic latent image and the fourth electrostatic latent image are rotated as the developing unit 24, and the magenta toner in the magenta developing device 7c as the third developing device and the fourth developing device are used. Development and primary transfer are sequentially performed with cyan toner in the cyan developing device 7d, and a toner image of each color is primarily transferred onto the intermediate transfer drum 25. The multiple toner image primarily transferred onto the intermediate transfer drum 25 is electrostatically applied onto the transfer material 15 by the action of the transfer bias voltage from the secondary transfer device 28 located on the opposite side via the transfer material 15. Secondary transfer is performed at once. The multiple toner image secondarily transferred onto the transfer material 15 is heated and fixed to the transfer material 15 by a fixing device 23 having a heating roller 17 and a pressure roller 18. The transfer residual toner remaining on the surface of the photosensitive drum 1 after the transfer is collected by a cleaner 19 having a cleaning blade in contact with the surface of the photosensitive drum 1, and the photosensitive drum 1 is cleaned.

  In the primary transfer from the photosensitive drum 1 to the intermediate transfer drum 25, a transfer current is obtained by applying a bias from a bias power source 26 to the conductive support 25 a of the intermediate transfer drum 25 serving as a primary transfer device. Is transferred.

  The intermediate transfer drum 25 includes a conductive support 25a that is a rigid body and an elastic layer 25b that covers the surface. As the conductive support 25a, a metal or an alloy such as aluminum, iron, copper, and stainless steel, and a conductive resin in which carbon or metal particles are dispersed can be used. The thing which penetrated the axis | shaft in the center, the thing which gave reinforcement to the inside of a cylinder, etc. are mentioned.

  The elastic layer 25b is not particularly limited, but styrene-butadiene rubber, high styrene rubber, butadiene rubber, isoprene rubber, ethylene-propylene copolymer, nitrile butadiene rubber (NBR), chloroprene rubber, butyl rubber, silicone. Elastomer rubbers such as rubber, fluorine rubber, nitrile rubber, urethane rubber, acrylic rubber, epichlorohydrin rubber and norbornene rubber are preferably used. A resin such as a polyolefin resin, a silicone resin, a fluorine resin, or a polycarbonate, and a copolymer or a mixture thereof may be used.

  Further, a surface layer in which lubricant powder having high lubricity and water repellency is dispersed in an arbitrary binder may be provided on the surface of the elastic layer 25b.

  The lubricant is not particularly limited, but various fluororubbers, fluoroelastomers, fluorocarbons and polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), ethylene-tetrafluoroethylene copolymers in which fluorine is bonded to graphite or graphite. (ETFE) and fluorine compounds such as tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), silicone compounds such as silicone resin particles, silicone rubber and silicone elastomer, polyethylene (PE), polypropylene (PP), polystyrene ( PS), acrylic resin, polyamide resin, phenol resin, epoxy resin and the like are preferably used.

  In addition, a conductive agent may be added to the surface layer binder in order to control resistance. Examples of the conductive agent include various conductive inorganic particles and carbon black, an ionic conductive agent, a conductive resin, and a conductive particle-dispersed resin.

  The multiple toner images on the intermediate transfer drum 25 are secondarily transferred collectively onto the transfer material 15 by the secondary transfer device 28. As the transfer device 28, a non-contact electrostatic transfer means or a transfer roller using a corona charger is used. Contact electrostatic transfer means using a transfer belt can be used.

  As the fixing device 23, instead of the heat roller fixing device having the heating roller 18 and the pressure roller 17, the toner image on the transfer material 15 is heated by heating the film in contact with the toner image on the transfer material 15. Also, a film heat fixing device that heat-fixes the multiple toner image on the transfer material 15 can be used.

  Instead of the intermediate transfer drum 25 as an intermediate transfer member used by the image forming apparatus shown in FIG. 3, it is also possible to batch transfer multiple toner images onto a recording material using an intermediate transfer belt. FIG. 4 shows a schematic configuration diagram of an apparatus using an intermediate transfer belt.

  In FIG. 4, 30 is an intermediate transfer belt, 31 is a roller for passing the intermediate transfer belt 30, 32 is a primary transfer roller, 33a is a secondary transfer counter roller, 33b is a secondary transfer roller, 34 to 36 are bias power supplies, 39 Is a cleaning charging member, and the same members as those in FIGS. 1 to 3 are denoted by the same reference numerals.

  4, the toner image formed and supported on the photosensitive drum 1 is applied from the primary transfer roller 32 to the intermediate transfer belt 30 in the process of passing through the nip portion between the photosensitive drum 1 and the intermediate transfer belt 30. The primary transfer is sequentially performed on the outer peripheral surface of the intermediate transfer belt 30 by the electric field formed by the primary transfer bias.

  A primary transfer bias for sequentially superimposing and transferring the first to fourth color toner images from the photosensitive drum 1 to the intermediate transfer belt 30 is applied from a bias power source 34 with a polarity opposite to that of the toner.

  In the primary transfer process of the first to fourth color toner images from the photosensitive drum 1 to the intermediate transfer belt 30, the secondary transfer roller 33 b and the cleaning charging member 39 can be separated from the intermediate transfer belt 30. .

  Reference numeral 33 b denotes a secondary transfer roller, which is supported in parallel with the secondary transfer counter roller 33 a and is arranged in a state in which it can be separated from the lower surface of the intermediate transfer belt 30.

  When the composite color toner image transferred onto the intermediate transfer belt 30 is transferred to the transfer material 15, the secondary transfer roller 33b is brought into contact with the intermediate transfer belt 30 and the intermediate transfer belt 30 and the secondary transfer roller 33b. The transfer material 15 is fed to the contact nip at a predetermined timing, and a secondary transfer bias is applied from the bias power source 36 to the secondary transfer roller 33b. The composite color toner image is secondarily transferred from the intermediate transfer belt 30 to the transfer material 15 by the secondary transfer bias.

  After the image transfer to the transfer material 15 is completed, a cleaning charging member 39 is brought into contact with the intermediate transfer belt 30 and a bias having a polarity opposite to that of the photosensitive drum 1 is applied from a bias power source 35 to the transfer material 15. A charge having a polarity opposite to that of the photosensitive drum 1 is imparted to the toner (transfer residual toner) remaining on the intermediate transfer belt 30 without being transferred. Next, the transfer residual toner is transferred to the photosensitive drum 1 in the vicinity of the nip portion with the photosensitive drum 1 and in the vicinity thereof, whereby the intermediate transfer belt 30 is cleaned.

  The intermediate transfer belt 30 includes a belt-shaped base layer and a surface treatment layer provided on the base layer. The surface treatment layer may be composed of a plurality of layers.

  Rubber, elastomer, or resin can be used for the base layer and the surface treatment layer. For example, as rubber and elastomer, natural rubber, isoprene rubber, styrene-butadiene rubber, butadiene rubber, butyl rubber, ethylene-propylene rubber, ethylene-propylene terpolymer, chloroprene rubber, chlorosulfonated polyethylene, chlorinated polyethylene, acrylonitrile butadiene rubber, Urethane rubber, syndiotactic 1,2-polybutadiene, epichlorohydrin rubber, acrylic rubber, silicone rubber, fluorine rubber, polysulfurized rubber, polynorbornene rubber, hydrogenated nitrile rubber and thermoplastic elastomer (for example, polystyrene, polyolefin, One type or two or more types selected from the group consisting of polyvinyl chloride, polyurethane, polyamide, polyester, fluororesin, and the like can be used. However, it is not limited to the above materials. As the resin, a resin such as a polyolefin resin, a silicone resin, a fluorine resin, or a polycarbonate can be used. A copolymer or a mixture of these resins may be used.

  As the base layer, the rubber, elastomer and resin described above can be used in the form of a film. In addition, a material obtained by coating, dipping, or spraying the above-described rubber, elastomer, or resin on one side or both sides of a core layer in the form of a woven fabric, a nonwoven fabric, a thread, or a film may be used.

  Materials constituting the core layer are, for example, natural fibers such as cotton, silk, hemp and wool; regenerated woven fibers such as chitin fiber, alginate fiber and regenerated cellulose fiber; semisynthetic fibers such as acetate fiber; polyester fiber, nylon Synthetic fibers such as fiber, acrylic fiber, polyolefin fiber, polyvinyl alcohol fiber, polyvinyl chloride fiber, polyvinylidene chloride fiber, polyurethane fiber, polyalkyl paraoxybenzoate fiber, polyacetal fiber, aramid fiber, polyfluoroethylene fiber and phenol fiber; carbon One or more selected from the group consisting of inorganic fibers such as fibers, glass fibers and boron fibers; metal fibers such as iron fibers and copper fibers can be used. Of course, the material is not limited to the above.

  Further, a conductive agent may be added to the base layer and the surface treatment layer in order to adjust the resistance value of the intermediate transfer belt 30. Although it does not specifically limit as a electrically conductive agent, For example, metal powder, such as carbon, aluminum, and nickel, metal oxides, such as a titanium oxide, and quaternary ammonium salt containing polymethyl methacrylate, polyvinyl aniline, polyvinyl pyrrole, One kind or two or more kinds selected from the group consisting of polydiacetylene, polyethyleneimine, boron-containing polymer compound, conductive polymer compound such as polypyrrole, and the like can be used. However, it is not limited to the said electrically conductive agent.

  Further, a lubricant may be added as necessary to increase the slipperiness of the surface of the intermediate transfer belt 30 and improve the transferability. The lubricant is not particularly limited, but various fluororubbers, fluoroelastomers, fluorocarbons bonded with fluorine to graphite or graphite, polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), ethylene-tetrafluoroethylene Fluorine compounds such as polymers (ETFE) and tetrafluoroethylene-perfluoroalkyl vinyl ether copolymers (PFA), silicone compounds such as silicone resins, silicone rubbers, silicone elastomers, polyethylene (PE), polypropylene (PP), polystyrene (PS), acrylic resin, polyamide resin, phenol resin, epoxy resin and the like are preferably used.

  Next, a schematic configuration diagram of an apparatus in which toner images of respective colors are formed in a plurality of image forming sections and transferred sequentially on the same transfer material will be described with reference to FIG.

  In FIG. 5, 1a to 1d are photosensitive drums, 19a to 19d are cleaners, 41a to 41d are image forming units, 42a to 42d are latent image forming means, 43a to 43d are transfer discharge units, and 44a to 44d are primary charges. , 45 is a static eliminator, 46 is a conveyor belt, 7a to 7d are developing devices, 48 is an adsorption charger, 49a to 49d are separation and neutralization discharge units, and 50 is a discharge port. Have the same symbols.

  In the configuration of FIG. 5, first to fourth image forming units 41a to 41d are arranged in parallel, and each image forming unit includes a photosensitive drum 1a to 1d which is a dedicated electrostatic latent image carrier. ing. Latent image forming means 42a to 42d, developing devices 7a to 7d, transfer discharge units 43a to 43d, cleaners 19a to 19d, and primary charging units 44a to 44d are arranged on the outer peripheral side of the photosensitive drums 1a to 1d.

  With such a configuration, first, for example, a yellow component color latent image in the original image is formed on the photosensitive drum 1a of the first image forming unit 41a by the latent image forming unit 42a. The latent image is made a visible image with yellow toner of the developing device 7a, and is transferred to the transfer material 15 by the transfer discharge portion 43a.

  As described above, while the yellow image is transferred to the transfer material 15, the second image forming unit 41b forms a magenta component color latent image on the photosensitive drum 1b, and then the magenta toner of the developing device 7b. Visible image. This visible image (magenta toner image) is transferred to a predetermined position of the transfer material 15 when the transfer material 15 that has been transferred by the first image forming portion 41a is transferred to the transfer discharge portion 42b. Is done.

  Thereafter, cyan and black images are formed in the third and fourth image forming portions 41c and 41d in the same manner as described above, and the cyan and black colors are superimposed on the same transfer material 15. It is transcribed. When such an image forming process is completed, the transfer material 15 is conveyed to the fixing device 23 to fix the image on the transfer material 15. As a result, a multicolor image is obtained on the transfer material 15. The photosensitive drums 1a to 1d after the transfer are removed from the residual toner by the cleaners 19a to 19d, and are used for subsequent latent image formation.

  In the image forming apparatus, the transfer belt 15 is used for transferring the transfer material 15. In FIG. 5, the transfer material 5 is transferred from the right side to the left side. Passes through the transfer discharge portions 43a to 43d in 41a to 41d and receives the transfer.

  In this image forming method, from the viewpoint of ease of processing and durability as a transport means for transporting the transfer material 15, a transport belt using a mesh of Tetoron fiber and polyethylene terephthalate resin, polyimide resin, urethane resin A conveyor belt using such a thin dielectric sheet is used.

  When the transfer material 15 passes through the fourth image forming unit 41d, a DC voltage is applied to the charge eliminator 45, the transfer material 15 is discharged, separated from the conveying belt 46, and then enters the fixing device 23 where the image is fixed. It is discharged from the discharge port 50.

  In this apparatus, each of the plurality of image forming units includes an independent electrostatic latent image carrier, and the transfer material is sequentially transferred to the transfer unit of each electrostatic latent image carrier by a belt-type conveying unit. The electrostatic latent image carrier that is common to the image forming unit is provided, and the transfer material is repeatedly sent to the transfer unit of the electrostatic latent image carrier by a drum-type conveyance unit. It may be configured to receive the transfer of each color.

  In the conveyance belt system of FIG. 5, since the volume resistance is high, the conveyance belt increases the charge amount in the process of repeating the transfer several times as in the color image forming apparatus. For this reason, uniform transfer cannot be maintained unless the transfer current is sequentially increased for each transfer. However, since the toner of the present invention has excellent transferability, the charge of the conveyor belt increases every time the transfer is repeated. Thus, the transferability of toner in each transfer can be made uniform with the same transfer current, and a high-quality high-quality image can be obtained.

  Further, FIG. 6 shows a schematic configuration diagram of another example of an apparatus for carrying out the image forming method of the present invention, which will be described below.

  In FIG. 6, 44 is a primary charging portion, 60 is a transfer drum, 61 is a gripper, 62 is a transfer charger, 63a and 63b are separation chargers, and 64 is a separation guide. The same symbols are attached.

  In the configuration of FIG. 6, the electrostatic latent image formed on the photosensitive drum 1 by suitable means is a first developing device in the developing devices 7a to 7d attached to the developing unit 24 that rotates in the direction of the arrow. In 7a, it is visualized by toner. The color toner image on the photosensitive drum 1 is transferred by the transfer charger 62 to the transfer material 15 held on the transfer drum 60 by the gripper 61. The transfer residual toner remaining on the surface of the photosensitive drum 1 after the transfer is collected by a cleaner 19 having a cleaning blade in contact with the surface of the photosensitive drum 1, and the photosensitive drum 1 is cleaned.

As the transfer charger 62, a corona charger or a contact charger is used. When the corona charger is used as the transfer charger 62, a voltage of -10 kV to +10 kV is applied, and the transfer current is -500 μA to +500 μA. It is. A holding member is stretched on the outer peripheral surface of the transfer drum 60, and this holding member is formed of a film-like dielectric sheet such as a polyvinylidene fluoride resin film or polyethylene terephthalate. For example, a sheet having a thickness of 100 μm to 200 μm and a volume resistance of 10 ¹² to 10 ¹⁴ Ω · cm is used.

  Next, the developing unit 24 rotates as the second color, and the developing device 7 b faces the photosensitive drum 1. The developing device 7b develops the second toner, and the toner image is also transferred onto the same transfer material 15 as described above.

  Further, the third color and the fourth color are similarly performed. In this way, the transfer drum 60 rotates a predetermined number of times while carrying the transfer material 15, and a toner image of a predetermined number of colors is transferred in a multiple manner. It is preferable to increase the transfer current for electrostatic transfer in order of the first color <second color <third color <fourth color in order to reduce the residual toner remaining on the photosensitive drum 1.

  The multiple transfer material 15 is separated from the transfer drum 60 by the separation chargers 63a and 63b, fixed by the heat and pressure roller fixing device 23, and added and mixed at the time of fixing to form a full-color copy image.

  FIG. 7 shows another example of an apparatus for carrying out the image forming method of the present invention. Secondary transfer at the time of secondary transfer of four color toner images that have been primary transferred onto an intermediate transfer drum onto a transfer material. As a means, a schematic configuration diagram of an image forming apparatus using a transfer belt is shown.

In the apparatus shown in FIG. 7, toners of respective colors of black, yellow, cyan, and magenta are introduced into the developing devices 7a to 7d, respectively, and the electrostatic latent image formed on the photosensitive drum 1 is developed. It is formed on the photosensitive drum 1. The photosensitive drum 1 has a photoconductive insulating material layer 71b such as a-Se, Cds, ZnO ₂ , OPC, or a-Si, and is rotated in the direction of the arrow by a driving device (not shown). As the photosensitive layer 71a, an amorphous silicon photosensitive layer or a photosensitive member having an organic photosensitive layer is preferably used.

  The organic photosensitive layer may be a single layer type in which the photosensitive layer contains a charge generation substance and a substance having charge transport performance in the same layer, or a function-separated type photosensitive layer having the charge generation layer as a component. It may be. A laminated photosensitive layer having a structure in which a charge generation layer and then a charge transport layer are laminated in this order on a conductive substrate is one preferred example.

  The binder resin for the organic photosensitive layer is particularly a polycarbonate resin, a polyester resin, or an acrylic resin, and has good transferability and cleaning properties, and poor cleaning, toner fusion to the photoreceptor, and filming of external additives are unlikely to occur.

  In the charging process, there are a non-contact method with the photosensitive drum 1 using a corona charger and a contact type method using a roller or the like, and either one is used, but efficient uniform charging, simplification, low In order to generate ozone, a contact type as shown in FIG. 7 is preferably used.

  The charging roller 10 is basically composed of a central cored bar 10b and a conductive elastic layer 10a formed on the outer periphery thereof. The charging roller 10 is pressed against the surface of the photosensitive drum 1 with a pressing force, and is driven to rotate as the photosensitive drum 1 rotates.

  Preferred process conditions when the charging roller 10 is used are the same as those in the apparatus of FIG.

  The toner image on the photosensitive drum 1 is transferred to the intermediate transfer drum 25 to which a voltage (for example, ± 0.1 to ± 5 kV) is applied. The surface of the photosensitive drum 1 after the transfer is cleaned by a cleaner 19 having a cleaning blade.

  The intermediate transfer drum 25 is disposed in parallel with the photosensitive drum 1 so as to be in contact with the lower surface portion of the photosensitive drum 1 and rotates in the counterclockwise direction of the arrow at the same peripheral speed as the photosensitive drum 1. To do.

  The first color toner image formed and supported on the surface of the photosensitive drum 1 passes through the transfer nip where the photosensitive drum 1 and the intermediate transfer drum 25 are in contact with each other, and the transfer nip is applied with the transfer bias applied to the intermediate transfer drum 25. The intermediate transfer is sequentially performed on the outer surface of the intermediate transfer drum 25 by the electric field formed in the area.

  If necessary, the surface of the intermediate transfer drum 25 is cleaned by the removable cleaning means 72 after the toner image is transferred onto the transfer material 15. When there is a toner image on the intermediate transfer drum 25, the cleaning means 72 is separated from the surface of the intermediate transfer drum 25 so as not to disturb the toner image.

  The transfer means is disposed by bearing in parallel with the intermediate transfer drum 25 and contacting the lower surface of the intermediate transfer drum 25. The transfer means is, for example, a transfer roller or a transfer belt, and rotates in the clockwise direction of the arrow at the same peripheral speed as that of the intermediate transfer drum 25. The transfer unit 73 may be disposed so as to be in direct contact with the intermediate transfer drum 25, or a belt or the like may be disposed between the intermediate transfer drum 25 and the transfer unit.

  When the transfer means is a transfer roller, the transfer roller is basically composed of a central cored bar and a conductive elastic layer forming the outer periphery thereof.

  Common materials can be used for the intermediate transfer drum and the transfer roller. By setting the volume specific resistance value of the elastic layer of the transfer roller to be smaller than the volume specific resistance value of the elastic layer 25b of the intermediate transfer drum 25, the voltage applied to the transfer roller can be reduced, and the transfer material 15 has a good value. A toner image can be formed and winding of the transfer material 15 around the intermediate transfer drum 25 can be prevented. In particular, the volume specific resistance value of the elastic layer 25b of the intermediate transfer drum 25 is particularly preferably 10 times or more than the volume specific resistance value of the elastic layer of the transfer roller.

  The hardness of the intermediate transfer drum and the transfer roller is measured according to JIS K-6301. The intermediate transfer drum 25 used in the present invention is preferably composed of an elastic layer 25b belonging to a range of 10 to 40 degrees, while the hardness of the elastic layer of the transfer roller is that of the elastic layer 25b of the intermediate transfer drum 25. What is harder than hardness and has a value of 41 to 80 degrees is preferable for preventing the transfer material 15 from being wound around the intermediate transfer drum 25. When the hardnesses of the intermediate transfer drum 25 and the transfer roller are reversed, a recess is formed on the transfer roller side, and the transfer material 15 is easily wound around the intermediate transfer drum 25.

  In FIG. 7, a transfer belt 73 is disposed below the intermediate transfer drum 25. The transfer belt 73 is stretched around two rollers arranged in parallel to the axis of the intermediate transfer drum 25, that is, a bias roller 74 and a tension roller 75, and is driven by a driving unit (not shown). The transfer belt 73 is configured so that the bias roller 74 side can move in the direction of the arrow about the tension roller 75 side, so that the transfer belt 73 can contact and separate from the intermediate transfer drum 25 in the direction of the arrow from below. A desired secondary transfer bias is applied to the bias roller 74 by a bias power supply 76 for secondary transfer, while the tension roller 75 is grounded.

Next, as the transfer belt 73, for example, carbon is dispersed in a thermosetting urethane elastomer, and the thickness is controlled to about 300 μm and the volume resistivity is 10 ⁸ to 10 ¹² Ω · cm (when 1 kV is applied). A rubber belt controlled to 20 μm and a volume resistivity of 10 ¹⁵ Ω · cm (when 1 kV is applied) is used. The outer diameter is a tube shape with a circumference of 80 × width of 300 mm.

  The transfer belt 73 is applied with a tension that extends by about 5% by the bias roller 74 and the tension roller 75 described above.

  The transfer belt 73 is rotated with a difference in speed or peripheral speed from the intermediate transfer drum 25. The transfer material 15 is conveyed between the intermediate transfer drum 25 and the transfer belt 73, and at the same time, a bias having a polarity opposite to the frictional charge of the toner is applied to the transfer belt 73 from the bias power source 76, thereby causing the intermediate transfer drum 25. The upper toner image is transferred to the surface side of the transfer material 15.

  The material for the transfer rotator can be the same as that of the charging roller. Preferred transfer process conditions include a roller contact pressure of 5 to 500 g / cm and a DC voltage of ± 0.2 to ± 10 kV.

For example, the conductive elastic layer 74b of the bias roller 74 is elastic with a volume resistance of about 10 ⁶ to 10 ¹⁰ Ωcm, such as polyurethane in which a conductive material such as carbon is dispersed, ethylene-propylene-diene terpolymer (EPDM), or the like. Made with body. A bias is applied to the core metal 74a by a constant voltage bias power source. The bias condition is preferably ± 0.2 to ± 10 kV.

  Subsequently, the transfer material 15 is conveyed to a fixing device 23 having a heating roller 18 incorporating a heating element such as a halogen heater and an elastic pressure roller 17 pressed against the heating roller 18 by a pressing force. By passing between 18 and the pressure roller 17, the toner image is heated and pressure-fixed on the transfer material 15. A method of fixing with a heater through a film may be used.

  The present invention will be specifically described below with reference to examples and comparative examples. In addition, “parts” in the following examples and the like are “parts by mass”.

(Preparation of release agent fine particle dispersion 1)
70 parts of ion-exchanged water, 30 parts of stearyl behenate and 1.7 parts of sodium dodecylbenzenesulfonate were mixed and emulsified by applying high-pressure shear at 90 ° C. to obtain a release agent fine particle dispersion 1. The average particle size was 320 nm.

(Preparation of release agent fine particle dispersion 2)
Dispersion 2 was obtained in the same manner as release agent fine particle dispersion 1 except that the release agent to be added was changed to 20 parts of stearyl behenate and 10 parts of polyethylene wax. The average particle size was 330 nm.

(Preparation of release agent fine particle dispersion 3)
Dispersion 3 was obtained in the same manner as release agent fine particle dispersion 1, except that the release agent to be added was changed to 20 parts of stearyl stearate and 10 parts of stearate ester of pentaerythritol. The average particle size was 350 nm.

(Preparation of release agent fine particle dispersion 4)
Dispersion 4 was obtained in the same manner as release agent fine particle dispersion 1, except that the release agent to be added was changed to 30 parts of pentaerythritol stearate. The average particle size was 300 nm.

(Preparation of release agent fine particle dispersion 5)
Dispersion 5 was obtained in the same manner as release agent fine particle dispersion 1, except that the parting agent to be added was changed to 30 parts of paraffin wax. The average particle size was 310 nm.

(Preparation of release agent fine particle dispersion 6)
Dispersion 6 was obtained in the same manner as release agent fine particle dispersion 1, except that the release agent to be added was changed to 30 parts of polyethylene wax. The average particle size was 400 nm.

(Preparation of colorant fine particle dispersion)
・ C. I. Pigment Blue 15: 3 25 parts by mass, anionic surfactant 2 parts by mass (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen SC)
-Ion exchange water 78 mass parts The above was mixed and it disperse | distributed using the sand grinder mill. When the particle size distribution in this colorant particle dispersion 1 was measured using a particle size measuring device (LA-920, manufactured by Horiba, Ltd.), the average particle size of the colorant particles contained was 0.25 μm and 1 μm. No coarse particles exceeding were observed.

(Adjustment of charge control fine particle dispersion)
-Di-alkyl-salicylic acid metal compound 20 parts by mass-Anionic surfactant 2 parts by mass (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen SC)
-Ion exchange water 78 mass parts The above was mixed and it disperse | distributed using the sand grinder mill. When the particle size distribution in this charge control fine particle dispersion 1 was measured using a particle size measurement device (LA-920, manufactured by Horiba, Ltd.), the average particle size of the charge control particles contained was 0.22 μm and 1 μm. No coarse particles exceeding were observed.

<Toner Production Example 1>
After the resin fine particle dispersion is synthesized by the emulsion polymerization method shown below, an agglomerated toner is produced.

(Preparation of resin fine particle dispersion 1)
In a reactor (with high shear stirring device, 1 liter flask), 400 parts by mass of ion-exchanged water and 3 parts by mass of 15% neogen SC were added and held at 85 ° C., and the release agent fine particle dispersion 1 Was added in an amount of 10 parts based on the total amount of monomers (solid content) and maintained at 85 ° C.

  Thereafter, the following monomers 1 and 10 parts by mass of ion-exchanged water in which 3.2 parts by mass of ammonium persulfate was dissolved as an initiator were added dropwise over 3 hours.

(Monomers 1)
Styrene 75 parts by mass nbutyl acrylate 23 parts by mass acrylic acid 2 parts by mass divinylbenzene 0.25 part by mass octanethiol 0.3 part by mass carbon tetrabromide 0.3 part by mass Further, 10 parts by mass of ion-exchanged water in which 1 part by mass of ammonium persulfate was dissolved and 1 part by mass of carbon tetrabromide were added at once, and emulsion polymerization was further performed for 3 hours to obtain a resin particle dispersion 1 having an average particle diameter of 400 nm. Obtained.

  In another reactor (volume 1 liter flask, anchor blade with baffle), 100 parts by mass (solid content) of the resin fine particle dispersion 1 obtained above and an anionic surfactant are charged and mixed uniformly before coloring. 7 parts by weight (solid content) of the agent fine particle dispersion and 7 parts (solid content) of the charge control agent fine particle dispersion were slowly added, and the temperature was slowly raised to 50 ° C. and uniformly mixed for 1 hour.

  After stirring for 1 hour, 0.1 part by mass of an aluminum sulfate aqueous solution as a solid content was dropped into the mixed dispersion, and the temperature was raised to 80 ° C. over 30 minutes.

Further, in order to strongly weld the aggregated particles, a 15% aqueous solution of neogen (2 parts solids) was added, and then the temperature was raised to 90 ° C. and held for 5 hours. After cooling, the reaction product was filtered, washed thoroughly with ion exchange water, and then fluidized bed dried at 45 ° C. to obtain toner particles 1. Toner 100 was obtained by stirring and mixing 1 part by mass of hydrophobic silica having a BET specific surface area of 100 (m ² / g) with 100 parts by mass of the toner particles. The physical properties of Toner 1 are shown in Table 1.

<Toner Production Example 2>
Toner 2 was obtained in the same manner as in Toner Production Example 1 except that release agent fine particle dispersion 2 was used instead of added release agent fine particle dispersion 1. The physical properties of Toner 2 are shown in Table 1.

<Toner Production Example 3>
In the toner production example 1, the release agent fine particle dispersion 3 is used in place of the added release agent fine particle dispersion 1, and the amount of carbon tetrabromide used when synthesizing the resin fine particle dispersion is 0.2 mass. Toner 3 was obtained using the same procedure except that the amount of divinylbenzene added was changed to 0.15 part by weight. The physical properties of Toner 3 are shown in Table 1.

<Toner Production Example 4>
In the toner production example 1, the release agent fine particle dispersion 4 is used in place of the added release agent fine particle dispersion 1, and the addition amount of divinylbenzene in the monomers constituting the resin fine particle dispersion is 0.05 parts by mass. Toner 4 was obtained using the same procedure except that The physical properties of Toner 4 are shown in Table 1.

<Toner Production Example 5>
In the toner production example 1, the release agent fine particle dispersion 4 is used instead of the added release agent fine particle dispersion 1, and the addition amount of octanethiol used when synthesizing the resin fine particle dispersion is 0.05 parts, Toner 5 was obtained using the same procedure except that the amount of carbon bromide added was changed to 0.1 parts by mass and hexanediol diacrylate was used instead of divinylbenzene. The physical properties of Toner 5 are shown in Table 1.

<Toner Production Example 6>
In the toner production example 1, the release agent fine particle dispersion 5 is used in place of the added release agent fine particle dispersion 1, and the amount of carbon tetrabromide used when synthesizing the resin fine particle dispersion is 0.2 mass. Toner 6 was obtained using the same procedure except that the amount of divinylbenzene added was changed to 0.15 part by weight. The physical properties of Toner 6 are shown in Table 1.

<Toner Production Example 7>
In the toner production example 1, the release agent fine particle dispersion 6 is used in place of the added release agent fine particle dispersion 1, and the amount of carbon tetrabromide used when synthesizing the resin fine particle dispersion is 0.2 mass. Toner 7 was obtained using the same procedure except that the amount of divinylbenzene added was changed to 0.15 part by weight. The physical properties of Toner 7 are shown in Table 1.

<Toner Production Example 8>
Toner 8 was obtained using the same procedure as in Toner Production Example 4 except that the amount of addition of release agent fine particle dispersion 4 was changed to 25 parts (solid content) with respect to the total amount of monomers. It was. The physical properties of Toner 8 are shown in Table 1.

<Toner Production Example 9>
A toner 9 was obtained in the same manner as in toner production example 4 except that the amount of the release agent fine particle dispersion 4 was changed to 4 parts (solid content) with respect to the total amount of monomers. It was. The physical properties of Toner 9 are shown in Table 1.

<Toner Production Example 10>
After the resin fine particle dispersion is synthesized by the emulsion polymerization method shown below, an agglomerated toner is produced.

(Preparation of resin fine particle dispersion 2)
In a reactor (with a high-shear stirring device, 1 liter flask), 400 parts by mass of ion exchange water and 3 parts by mass of 15% neogen SC were added and held at 85 ° C. Was added in an amount of 10 parts based on the total amount of monomers (solid content) and maintained at 85 ° C.

  Thereafter, the following monomers 1 and 10 parts by mass of ion-exchanged water in which 3.2 parts by mass of ammonium persulfate was dissolved as an initiator were added dropwise over 7 hours.

(Monomers 2)
・ 75 parts by mass of styrene 23 parts by mass of n-butyl acrylate 2 parts by mass of acrylic acid 0.3 parts by mass of divinylbenzene 0.3 parts by mass of octanethiol 0.3 parts by mass of carbon tetrabromide Cool after completion of the polymerization reaction A resin fine particle dispersion 2 having an average particle diameter of 200 nm was obtained.

  In another reactor (volume 1 liter flask, anchor blade with baffle), 100 parts by mass (solid content) of the resin fine particle dispersion 2 obtained above and an anionic surfactant are charged and mixed uniformly before coloring. 7 parts by weight (solid content) of the agent fine particle dispersion and 7 parts (solid content) of the charge control agent fine particle dispersion were slowly added, and the temperature was slowly raised to 50 ° C. and uniformly mixed for 1 hour.

  After stirring for 1 hour, 0.1 part by mass of an aluminum sulfate aqueous solution as a solid content was dropped into the mixed dispersion, and the temperature was raised to 80 ° C. over 30 minutes.

Further, in order to strongly weld the aggregated particles, a 15% aqueous solution of neogen (2 parts solids) was added, and then the temperature was raised to 90 ° C. and held for 5 hours. After cooling, the reaction product was filtered, washed thoroughly with ion exchange water, and then fluidized bed dried at 45 ° C. to obtain toner particles 10. To 100 parts by mass of the toner particles, 1 part by mass of hydrophobic silica having a BET specific surface area of 100 (m ² / g) was stirred and mixed to obtain toner 10. The physical properties of the toner 10 are shown in Table 1.

<Toner Production Example 11>
Toner 11 was obtained in the same manner as in Toner Production Example 10 except that the release agent fine particle dispersion was not added. The physical properties of the toner 11 are shown in Table 1.

<Toner Production Example 12>
In Toner Production Example 10, the amount of octanethiol used in synthesizing the resin fine particle dispersion was changed to 0.4 part, and the amount of carbon tetrabromide added was changed to 0.4 parts by weight. Instead of divinylbenzene, hexane was used. A toner 12 was obtained using the same procedure except that the diol diacrylate was used. The physical properties of the toner 12 are shown in Table 1.

<Toner Production Example 13>
In Toner Production Example 10, the amount of octanethiol used to synthesize the resin fine particle dispersion was changed to 0.05 parts and the amount of carbon tetrabromide added was changed to 0.05 parts by weight, and hexane was used instead of divinylbenzene. A toner 13 was obtained using the same procedure except that the diol diacrylate was used. The physical properties of the toner 13 are shown in Table 1.

（画像評価）
得られたトナー１乃至トナー13を用い、以下の方法に従って画像評価を行った。
画像形成装置としては市販のレーザプリンタＬＢＰ−２５１０（キヤノン製）を用い、常温常湿条件下（２３℃、４０％ＲＨ）でＡ４のＣＬＣ用紙（キヤノン製、８０ｇ／ｍ^２）を用いて行った。

(Image evaluation)
Using the obtained toner 1 to toner 13, image evaluation was performed according to the following method.
As the image forming apparatus, a commercially available laser printer LBP-2510 (manufactured by Canon) was used, and A4 CLC paper (manufactured by Canon, 80 g / m ² ) was used under normal temperature and humidity conditions (23 ° C., 40% RH). It was.

  The cartridge used for evaluation was a cyan cartridge. That is, the product toner was extracted from a commercially available cyan cartridge, the interior was cleaned by air blow, and then 180 g of the toner according to the present invention was filled for evaluation. In addition, the product toner was extracted from each of the magenta, yellow, and black stations, and evaluation was performed by inserting magenta, yellow, and black cartridges in which the toner remaining amount detection mechanism was disabled.

  As an evaluation image, an original chart with a printing ratio of 5% was used, 5000 continuous prints were performed, and image quality before and after durability was evaluated.

<Gascal image evaluation>
For the evaluation of the rough image, a halftone image was output before and after the endurance of 5000 sheets, and the fineness was visually evaluated. The durability evaluation was performed on an original chart with a total of 5000 sheets and a printing ratio of 5% in each environment.

A: The image after passing 5000 sheets is also uniformly fine.
B: The image after 5,000 sheets has also faded.
C: It is haze without waiting for 5000 sheets to pass.
D: Without waiting for 5000 sheets to pass, a conspicuous shading and a defective image occurred.

<Image fog>
To measure fog, use REFECTOMETER MODEL TC-6DS (manufactured by Tokyo Denshoku Co., Ltd.) (use amber filter), measure the reflectivity of standard paper and solid white pattern samples, calculate from the following formula, and judge from the values did. The initial fog was evaluated using a 10 sheet sample, and the durable fog was evaluated using a 5000 sheet sample.

A: Less than 0.05% B: 0.05% or more and less than 1.0% C: 1.0% or more and less than 3.0% D: 3.0% or more fog (reflectance;%) = (standard paper Reflectance:%)-(Sample reflectance:%)
(Low-temperature fixability evaluation)
The low temperature fixability was evaluated by the peelability of a fixed image by a rubbing test of a halftone image having a Macbeth density of 0.7 to 0.8. Before and after the endurance evaluation, a 1 cm square halftone patch was output, and the patch was rubbed 5 times with a weight of 50 g / cm 2 wrapped with sylbon paper. ) Was used to calculate the concentration reduction rate.

A: Density reduction rate less than 10% B: Density reduction rate 10% or more and less than 15% C: Density reduction rate 15% or more and less than 25% D: Density reduction rate 25% or more

It is explanatory drawing of the toner layer control member in the image forming method of this invention. It is a schematic block diagram of an example of the apparatus which implements the image forming method of this invention. It is a schematic block diagram of the other example of the apparatus which enforces the image forming method of this invention. It is a schematic block diagram of the other example of the apparatus which enforces the image forming method of this invention. It is a schematic block diagram of the other example of the apparatus which enforces the image forming method of this invention. It is a schematic block diagram of the other example of the apparatus which enforces the image forming method of this invention. It is a schematic block diagram of the other example of the apparatus which enforces the image forming method of this invention. It is the GPC chart which showed typically La, Lb, Sa, and Sb of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 1a-1d Photosensitive drum 2 Developing sleeve 3 Elastic regulation blade 4 Toner 5 Toner container 6 Presser metal plate 7, 7a-7d Developing device 9 Coating roller 10 Charging roller 10a Conductive elastic layer 10b Core metal 11-13 Bias power supply 14 Exposure 15 Transfer material 16 Transfer member 17 Pressure roller 18 Heating roller 19, 19a to 19d Cleaner 21 Light source device 22 Laser light 23 Fixing device 24, 51 Development unit 25 Intermediate transfer drum 25a Conductive support 25b Elastic layer 26 Bias power supply 27 Transfer material tray 28 Secondary transfer device 30 Intermediate transfer belt 31 Roller 32 Primary transfer roller 33a Secondary transfer counter roller 33b Secondary transfer roller 34 to 36 Bias power supply 39 Charging member for cleaning 41a to 41d Image forming unit 42a to 42d Latent image Forming means 43a to 43d Transfer discharge portion 44, 44a to 44d Primary charging portion 45 Static eliminator 46 Conveyor belt 48 Adsorption charger 49a to 49d Separation static elimination discharge portion 50 Discharge port 60 Transfer drum 61 Gripper 62 Transfer charger 63a, 63b Separation charger 64 Separation guide 71a Photosensitive layer 71b Photoconductive insulating material layer 72 Cleaning means 73 Transfer belt 74 Bias roller 74a Core metal 74b Conductive elastic layer 75 Tension roller 76 Bias power supply

Claims (28)

It contains at least a colorant, a binder resin, and a release agent, has a volume average particle size of 4 to 10 μm, a shape factor SF-1 of 115 to 140, and an average circularity of 0.950 to 0.990. The BET specific surface area is 2.0 to 7.0 m ² / g,
In the GPC chart with the horizontal axis representing the logarithm of molecular weight in gel permeation chromatography (GPC) measurement of toluene soluble components,
Having at least one peak in the region of molecular weight 45000 or more and 100,000 or less,
When a line is drawn horizontally from the base line at half the height of the main peak, the linear length of the lower molecular weight component than the main peak molecular weight (Mp) is La, and the linear length of the higher molecular weight component than Mp is Lb. The following relational expression (1) holds,
In the molecular weight integral value of the region having a molecular weight of 3000 or more, the following relational expression (2) is established, where Sa is the integral value of the low molecular weight component from Mp, and Sb is the integral value of the high molecular weight component from Mp.
A toner having a toluene insoluble content of 45% or less.
La / Lb> 1 Relational expression (1)
Sa / Sb> 1 Relational expression (2) The toner according to claim 1, wherein La and Lb satisfy the following relational expression (3).
3.0> La / Lb> 1.1 Relational expression (3) 3. The toner according to claim 1, wherein Sa and Sb satisfy the following relational expression (4).
6.0> Sa / Sb> 1.1 Relational expression (4)   4. The toner according to claim 1, wherein the toner release agent is an ester wax, and the maximum endothermic peak of the toner measured by a differential scanning calorimeter (DSC) is 45 ° C. or higher and 70 ° C. or lower. The toner described. 5. The toner according to claim 1, wherein the toner release agent has the following structural formula, and the maximum endothermic peak of the toner measured by a differential scanning calorimeter (DSC) is 45 ° C. or more and 70 ° C. or less. The toner described in 1.

(Wherein, a and b are integers from 0 to 4, and a + b is 4. R ₁ and R ₂ are organic groups having 1 to 40 carbon atoms, and the number of carbon atoms of R ₁ and R ₂ The difference is less than 3. m and n are integers from 0 to 40, and m and n cannot be 0 at the same time.   The toner contains two or more types of release agents, and has a maximum endothermic peak by a differential scanning calorimeter (DSC) of more than 70 ° C. and 130 ° C. or less, and has at least one endothermic peak. The toner according to claim 4.   The toner according to any one of claims 1 to 6, wherein the amount of the releasing agent added is 5 to 20 parts by weight.   The toner according to claim 1, wherein the toner has an MI value of 0.1 to 20 at 125 ° C. under a 5 kg load. An image forming method using a non-magnetic one-component developing method, wherein the image forming method includes a toner layer forming step of regulating a toner layer on the toner carrier by bringing a toner regulating member into contact with the surface of the toner carrier; A development step of developing the electrostatic latent image to form a toner image on the electrostatic latent image carrier by bringing the toner layer carried on the surface of the carrier into contact with the surface of the electrostatic latent image carrier; Having at least
The toner regulating member has a universal hardness of 9.5 N / mm ² or more and less than 100 N / mm ² , and the toner contains at least a colorant, a binder resin, and a release agent, and has a volume average diameter of 4 to 4. 10 μm, the shape factor SF-1 is 115 to 140, the average circularity is 0.950 to 0.990, the specific surface area is 2.0 to 7.0 (m ² / g),
In GPC measurement of toluene-soluble components in the GPC chart with the horizontal axis representing the logarithm of molecular weight,
Having at least one peak in the region of molecular weight 45000 or more and less than 100,000,
When a line is drawn horizontally from the base line at half the height of the main peak, the linear length of the lower molecular weight component than the main peak molecular weight (Mp) is La, and the linear length of the higher molecular weight component than Mp is Lb. The following relational expression (1) holds,
In the molecular weight integral value of the region having a molecular weight of 3000 or more, the following relational expression (2) is established, where Sa is the integral value of the low molecular weight component from Mp, and Sb is the integral value of the high molecular weight component from Mp.
An image forming method, wherein a toluene insoluble content is 45% or less.
La / Lb> 1 Relational expression (1)
Sa / Sb> 1 Relational expression (2)   The image forming method according to claim 9, wherein the image forming method includes an auxiliary charging step in which charging of the toner particles regulated in the toner layer forming step is controlled by an auxiliary charging member in contact with the toner carrier. Forming method.   The image forming method according to claim 9, wherein the toner layer regulating member has an elastic layer containing a nitrogen-containing compound on a surface layer thereof. The image forming method according to any one of claims 9 to 11, wherein La and Lb satisfy the following relational expression (3).
3.0> La / Lb> 1.1 Relational expression (3) The image forming method according to claim 9, wherein Sa and Sb satisfy the following relational expression (4).
6.0> Sa / Sb> 1.1 Relational expression (4)   14. The toner according to claim 9, wherein the toner release agent is an ester wax, and the maximum endothermic peak of the toner measured by a differential scanning calorimeter (DSC) is 45 ° C. or higher and 70 ° C. or lower. The image forming method described. The toner release agent is represented by the following structural formula, and the maximum endothermic peak of the toner measured by a differential scanning calorimeter (DSC) is 45 ° C. or higher and 70 ° C. or lower. The image forming method described in 1.

(Wherein, a and b are integers from 0 to 4, and a + b is 4. R ₁ and R ₂ are organic groups having 1 to 40 carbon atoms, and the number of carbon atoms of R ₁ and R ₂ The difference is less than 3. m and n are integers from 0 to 40, and m and n cannot be 0 at the same time.   The toner contains two or more types of release agents, and has a maximum endothermic peak by a differential scanning calorimeter (DSC) of more than 70 ° C. and 130 ° C. or less, and has at least one endothermic peak. The image forming method according to claim 14.   The image forming method according to claim 9, wherein the amount of the release agent added is 1 to 20 parts by weight.   18. The image forming method according to claim 9, wherein the toner has an MI value of 0 to 20 at 125 ° C. under a 5 kg load. A process cartridge used for forming an image by a non-magnetic one-component developing method, wherein the process cartridge is in contact with a toner containing portion, a toner carrier, and the toner carrier to remove toner on the carrier. At least a toner regulating member for regulating, and an electrostatic latent image carrier, and the electrostatic latent image carrier is arranged to develop the electrostatic latent image by being brought into contact with the toner carrier. The toner regulating member has a universal hardness of 9.5 N / mm ² or more and less than 100 N / mm ² , and the toner contains at least a colorant, a binder resin, and a release agent, and has a volume average diameter. Is 4 to 10 μm, the shape factor SF-1 is 115 to 140, the average circularity is 0.950 to 0.990, the specific surface area is 2.0 to 7.0 (m ² / g),
In GPC measurement of toluene-soluble components in the GPC chart with the horizontal axis representing the logarithm of molecular weight,
Having at least one peak in the region of molecular weight 45000 or more and less than 100,000,
When a line is drawn horizontally from the base line at half the height of the main peak, the linear length of the lower molecular weight component than the main peak molecular weight (Mp) is La, and the linear length of the higher molecular weight component than Mp is Lb. The following relational expression (1) holds,
In the molecular weight integral value of the region having a molecular weight of 3000 or more, the following relational expression (2) is established, where Sa is the integral value of the low molecular weight component from Mp, and Sb is the integral value of the high molecular weight component from Mp.
A process cartridge having a toluene insoluble content of 45% or less.
La / Lb> 1 Relational expression (1)
Sa / Sb> 1 Relational expression (2)   The process cartridge includes an auxiliary charging member that comes into contact with the toner carrying member between the time when the toner passes through the toner regulating member and the time when the toner comes into contact with the electrostatic latent image carrying member. Item 20. The process cartridge according to Item 19.   21. The process cartridge according to claim 19, wherein the toner layer regulating member has an elastic layer containing a nitrogen-containing compound on a surface layer thereof. The process cartridge according to any one of claims 19 to 21, wherein La and Lb satisfy the following relational expression (3).
3.0> La / Lb> 1.1 Relational expression (3) The process cartridge according to any one of claims 19 to 22, wherein Sa and Sb satisfy the following relational expression (4).
6.0> Sa / Sb> 1.1 Relational expression (4)   24. The toner according to claim 19, wherein the toner release agent is an ester wax, and the maximum endothermic peak of the toner measured by a differential scanning calorimeter (DSC) is 45 ° C. or higher and 70 ° C. or lower. The described process cartridge. 25. The toner according to claim 19, wherein the toner release agent has the following structural formula, and the maximum endothermic peak of the toner measured by a differential scanning calorimeter (DSC) is 45 ° C. or higher and 70 ° C. or lower. Process cartridge according to.

(Wherein, a and b are integers from 0 to 4, and a + b is 4. R ₁ and R ₂ are organic groups having 1 to 40 carbon atoms, and the number of carbon atoms of R ₁ and R ₂ The difference is less than 3. m and n are integers from 0 to 40, and m and n cannot be 0 at the same time.   The toner contains two or more release agents, and the toner has at least one endothermic peak at a maximum endothermic peak by a differential scanning calorimeter (DSC) of more than 70 ° C. and not more than 130 ° C. The process cartridge according to any one of claims 24 to 25.   27. The process cartridge according to claim 19, wherein the amount of the release agent added is 1 to 20 parts by weight.   The process cartridge according to any one of claims 19 to 27, wherein the toner has an MI value of 0.1 to 20 at 125 ° C and a load of 5 kg.

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