JP2003207940A - Toner and image forming method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide toners which do not give rise to image streaks and image fogging and can obtain high-grade images even in long-term use in both environments of the high-temperature and high-humidity environmental conditions and low-temperature and low-humidity environmental conditions. <P>SOLUTION: The nonmagnetic one-component toners are characterized in that a toner layer regulating member on a toner carrying member has a resin layer having resistance above 1.00×10<SP>4</SP>Ω.cm; the thickness of the resin layer is ≥5 and ≤50 μm; the toners contain a polyester compound at ≥50 mass% in a binder resin component; the compound has a main peak between 1.00×10<SP>3</SP>and 3.00×10<SP>4</SP>and has a toluene insoluble component at ≥1 and <70 mass%; the moisture content under the low temperature and low humidity of the toners is 100 to 5,000 ppm; and the toner particles of the grain size exceeding 16 μm are below 5 vol.%. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a toner for developing an electrostatic charge image used in an electrostatic copying machine, a laser printer or the like, and also to an image forming method using the toner. .

[0002]

2. Description of the Related Art Conventionally, styrene-acrylic resins, polyester resins, epoxy resins and the like have been known as binder resins used in toners. Among them, the polyester resin is a binder resin because of its excellent charging characteristics and offset resistance, excellent image transparency when an overhead projector (OHP) film is used as a transfer material, and relatively low cost. Is preferably used as.

As a means for regulating the amount of toner supplied by the toner supply member, a regulating member such as a thin metal plate is brought into contact with the supply member to uniformly charge the toner particles, and the toner on the toner supply member is also charged. A method of making the toner layer have a constant thickness is widely known.

The toner layer restriction member will be described with reference to FIG.

In FIG. 1, reference numeral 5 denotes a toner container for containing a non-magnetic toner 4 as a one-component developer, and an electrostatic latent image bearing member is held in an opening extending in the toner container 5 in the longitudinal direction. A developing roller 2 as a toner carrier, which is arranged to face the photosensitive drum 1 as a body, is rotatably arranged. Further, the developing roller 2 is horizontally installed so that the right half peripheral surface shown in the drawing projects into the toner container 5 at the opening of the toner container 5 and the left half peripheral surface is exposed to the outside of the toner container 5.

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

When a thin metal plate is used as the toner regulating member, there are problems that the toner particles are fused to the member, the charge imparting ability is insufficient, and the like. Therefore, various methods have been conventionally proposed as means for solving this problem.

For example, Japanese Patent Application Laid-Open No. 8-22149 discloses that
A method is disclosed in which a toner layer is provided with a silicone layer on the surface thereof to uniformly charge the toner particles. Further, JP-A-9-50185 and JP-A-11-
JP-A-288166 discloses a room temperature environment in which a polyamide elastomer layer is provided on the surface of a toner regulating member.
A method for preventing streaks and unevenness in a low temperature and low humidity environment is described. Further, Japanese Patent Application Laid-Open No. 2000-321820 describes a method of preventing the toner fusion on a member by defining the molecular weight distribution of the toner and keeping a uniform coat layer.

Based on these findings, the present inventors have made a detailed study on image characteristics when a toner using a polyester resin as a main binder resin is used for a long period of time in various environments. It was As a result, by using only the conventional technique, a character image is mainly used under both high temperature and high humidity conditions (temperature 30 ° C., relative humidity 80%) and low temperature low humidity conditions (temperature 15 ° C., relative humidity 10%). It has been found that it is difficult to continuously obtain a suitable image for a long period of time when printing the image with the low printing rate. Specifically, under high-temperature and high-humidity conditions, image streaks caused by toner fusing to the regulation member; image fog caused by poor charging occurred. Also, under low temperature and low humidity conditions, image streaks due to excessive charging of the toner (charge-up); since the charged-up toner does not separate from the supply member, the charge imparting ability and the dynamic friction coefficient are not stable at that portion. Image fogging occurred.

[0010]

SUMMARY OF THE INVENTION An object of the present invention is to obtain a high-quality image without causing image streaks and image fog even during long-term use in both high temperature and high humidity conditions and low temperature and low humidity conditions. To provide toner.

Further, an object of the present invention is to provide an image forming method capable of obtaining a high-quality image without causing image streaks and image fog even in a long-term use under both high temperature and high humidity conditions and low temperature and low humidity conditions. It is provided.

[0012]

The present invention relates to a toner for forming an image by using a non-magnetic one-component developing system, in which a toner layer on a toner carrier is regulated by a toner regulating member. It is applied to an image forming method having at least a forming step, and the regulating member is 1.00 × 10 ⁴
At least a resin layer having a resistance of Ω · cm or more,
The resin layer has a thickness of 5 μm or more and less than 50 μm, the toner has at least a binder resin and a colorant, and contains a polyester compound in an amount of 50% by mass or more of the binder resin component. In the gel permeation chromatography (GPC) measurement of the soluble component, 1.0
The toner has a main peak between 0 × 10 ^{3 and} 3.00 × 10 ⁴ , the toluene insoluble component of the toner is 1% by mass or more and less than 70% by mass, and the toner is left under low temperature and low humidity conditions for 24 hours. When water content is 100ppm or more 5000p
5 toner particles having a particle size of less than pm and a particle size of more than 16 μm.
The present invention relates to a toner having a particle size distribution of less than volume% and an image forming method using the toner.

[0013]

DETAILED DESCRIPTION OF THE INVENTION As a result of intensive investigations by the present inventors, in order to obtain a high-quality image even in long-term use under both high temperature and high humidity conditions and low temperature and low humidity conditions, the toner is 1) Water content, 2) Peak top position by GPC measurement, 3) Toluene insoluble component content, 4) Coarse particle content are defined, and for the toner layer regulating member surface, 5) A resin layer is provided on the surface layer. , 6) The resistance value of the resin layer and 7) the film thickness of the resin layer are defined, respectively, and it has been found that the object is preferably achieved.

The effects will be described in detail below in the order of items.

1) Water Content The water content of the toner is preferably 100 ppm or more and less than 5000 ppm, more preferably 300 ppm or more and 3000 pp.
More preferably, it is less than m.

The water content is considered to have a correlation with the total charge amount of the toner. By defining the water content of the toner within the above range, it is possible to suitably control the total charge amount of the toner under low temperature and low humidity conditions.

If the water content is less than 100 ppm, the toner is excessively charged, which causes development streaks, which is not preferable.

On the other hand, if the water content exceeds 5000 ppm, overcharge of the toner can be prevented under low temperature and low humidity conditions, but the toner cannot be sufficiently and uniformly charged in the initial image, which causes image fog, which is not preferable. .

In the present invention, the "moisture content" means the mass-based water content based on the Karl Fischer method, that is, the ratio of the mass of water to the total mass of the toner, at low temperature and low humidity (15 ° C, 10% RH). The sample was prepared by leaving it for 24 hours and using the Karl Fischer method (JIS K-
It was obtained by measuring the gas in heating at 125 ° C. based on the water vaporization method).

2) Peak top position by GPC measurement In the present invention, 1.00 × 10 in GPC measurement.
It preferably has a main peak between ^{3 and} 3.00 × 10 ⁴ . Furthermore, the main peak position is 3.00
More preferably, it is between × 10 ^{3 and} 1.00 × 10 ⁴ .

It is considered that the peak position of the GPC measurement has a correlation with the rising speed of the toner charging / and the toner fusion to the charging member.

When the main peak exceeds 3.00 × 10 ⁴ , the toner particles cannot be rapidly charged, so that a uniform image cannot be obtained in the initial image under low temperature and low humidity conditions, which is not preferable. . On the other hand, when the main peak is less than 1.00 × 10 ³ , the toner particles are rapidly charged, but low molecular weight substances contained in a large amount in the toner are fused to the charging member and contaminate the charging member. Not preferable.

Contamination of the charging member by the low molecular weight substance is a phenomenon which is noticeable not only under low temperature and low humidity conditions but also under high temperature and high humidity conditions.

In the present invention, the peak top molecular weight (Mp), the number average molecular weight (Mn), and the weight average molecular weight (Mw) of the toluene soluble content of the chromatogram by GPC (gel permeation chromatography) are as follows. Measured at.

First, as a sample preparation, the resin component in the sample was dissolved in toluene at room temperature so that the resin component was 0.4 to 0.6 mg / ml, and the resulting solution had a pore size of 0.2.
Filter with a μm solvent resistant membrane filter.

Next, the column was stabilized in a heat chamber at 40 ° C., and tetrahydrofuran (TH
F) at a flow rate of 1 ml / min, and the THF sample solution is added to about 1
Inject 00 μl and measure. In measuring the molecular weight of the sample, the molecular weight distribution of the sample was calculated from the relationship between the logarithmic value and the count number of the calibration curve prepared from several kinds of monodisperse polystyrene standard samples. As a standard polystyrene sample for preparing a calibration curve, TSK standard polystyrene F-850, F-450, F-28 manufactured by Tosoh Corporation
8, F-128, F-80, F-40, F-20, F-
10, F-4, F-2, F-1, A-5000, A-2
The calibration curve was created using 500, A-1000, and A-500. The detectors are RI (refractive index) detector and UV.
The (ultraviolet) detector was used by being arranged in series. As the column, it is preferable to combine a plurality of commercially available polystyrene gel columns, and in the present invention, sh manufactured by Showa Denko KK is used.
odex GPC KF-801, 802, 803, 8
The measurement was performed using a combination of 04, 805, 806, 807 and 800P.

The apparatus is a high speed GPC HPLC8120.
GPC (manufactured by Tosoh Corporation) was used.

3) Toluene insoluble component content In the present invention, the toluene insoluble component of the toner is 1% by mass.
It is preferably contained in the range of 70% by mass or more and less than 70% by mass. Furthermore, it is more preferable that the toluene insoluble component is 10% by mass or more and less than 60% by mass.

Here, the toluene-insoluble component reflects the gel content in the toner, and the gel content is considered to have a correlation with the charging uniformity of the toner. That is, the elasticity of the toner particles is increased by appropriately containing the gel content, and permanent deformation of the toner particles due to friction with the charging member is suppressed. As a result, it is possible to prevent the charging characteristics of the toner particles from varying even during long-term use.

When the toluene insoluble component of the toner is less than 1% by mass, that is, when the toner does not substantially contain a gel component, the charging characteristics of the toner particles vary with long-term use.
A uniform image cannot be obtained, which is not preferable. On the other hand, when the toluene insoluble component of the toner exceeds 70% by mass, the effect of the above 2) cannot be exhibited properly, which is not preferable.

The toluene insoluble content is defined as the value measured as follows.

About 1.0 g of the toner sample is weighed (W1
g), put it in a cylindrical filter paper (for example, No. 86R manufactured by Toyo Roshi Kaisha, Ltd.), apply it to a Soxhlet extractor, and use toluene 1 as a solvent.
The mixture is refluxed and extracted with 00 to 200 ml for 6 hours, and the soluble component extracted with a toluene solvent is evaporated, followed by vacuum drying at 100 ° C. for several hours, and the amount of the toluene-soluble resin component is weighed (W2g). The toluene insoluble content in the toner is calculated from the following formula. Toluene insoluble matter (mass%) = {(W1-W2) / W1}
× 100

4) Content of Coarse Grain Particles In the present invention, it is preferable that the toner particles having a particle diameter of more than 16 μm have a particle size distribution of 5% by volume. When the particle size distribution of the toner satisfies the above range, it is possible to prevent coarse particle from being caught in the nip portion between the toner supply member and the toner regulating member and disturbing the coating layer pressure.

The average particle size and particle size distribution of the toner are
Although it is possible to measure by various methods such as Coulter counter TA-II type or Coulter Multisizer (manufactured by Coulter), in the present invention, Coulter counter TA-II type (manufactured by Coulter) is used.

The measuring method will be described below.

(Particle size distribution measuring method) As the electrolytic solution, an about 1% NaCl aqueous solution was prepared using primary sodium chloride and used. In the present invention, ISOTON-II (manufactured by Coulter)
It was used. As a measuring method, the electrolytic aqueous solution 100 is used.
0.1 to 5 ml of a surfactant (preferably alkylbenzene sulfonate) as a dispersant in 150 ml of
In addition, 2 to 20 mg of the measurement sample was further added. About 1 with an ultrasonic disperser for the electrolyte that became a suspension system by adding the sample
After performing the dispersion treatment for 3 minutes,
The volume and number of toner particles were measured using a 100 μm aperture as an aperture, and the volume distribution and number distribution were calculated. Then, the weight-based weight average particle diameter (D4) of the toner particles was calculated, and the abundance ratio (volume%) of the toner having a particle diameter of more than 16 μm was calculated.

The channels are 1.59 to 2.00.
Less than μm; 2.00 to less than 2.52 μm; 2.52
3.18 μm or less; 3.18 to 4.00 μm or less;
0.00 to less than 5.04 μm; 5.04 to less than 6.35 μm; 6.35 to less than 8.00 μm; 8.00 to 10.0
Less than 8 μm; 10.08 to less than 12.70 μm;
70 to less than 16.00 μm; 16.0 to 20.16 μ
less than m; 20.16 to less than 25.40 μm; 25.40
~ 32.00 μm; 32.00-40.32 μm; 40.32-50.80 μm; 50.80-6
Using 16 channels less than 4.00 μm, particle size 1.
Particles of 59 μm or more and less than 64.00 μm were targeted. “Toner particles having a particle size exceeding 16 μm” according to the present invention
Is 16.0 to less than 20.16 μm; 20.16 to 2
Less than 5.40 μm; 25.40 to less than 32.00 μm;
32.00 to less than 40.32 μm; 40.32 to 50.
The toner contained in 6 channels of less than 80 μm; 50.80 to 64.00 μm is shown.

Next, the toner layer regulating member will be described.

5) Setting a resin layer on the surface In the present invention, it is preferable to provide a resin layer on the surface of the regulating member. As a result, it is possible to obtain a suitable image for a long period of time even in a usage mode in which the toner continues to have a large share, such as low-printing printing for a long period of time.
If the resin layer is not provided, it is not preferable because in the high temperature and high humidity environment, the toner is not properly charged, and in the low temperature and low humidity environment, aggregation of the toner is promoted and a suitable image cannot be obtained.

Any of the above resins can be used, but specifically, polycarbonate, polypropylene,
Resins such as polyurethane and polyamide elastomer can be used. In the present invention, a polyamide elastomer is preferably used from the viewpoints of abrasion resistance, low temperature characteristics, molding processability, charging characteristics and the like.

When a polyamide elastomer is used as the resin, the saturated water absorption of the polyamide elastomer is preferably less than 1.2%, more preferably 1.0%.
It is more preferably less than. By setting the saturated water absorption in the above range, favorable charging characteristics can be obtained even under high temperature and high humidity conditions.

6) Resistance Value In the present invention, the resin layer on the surface of the regulating member has a resistance value of 1.
It is preferably one having a resistance of 00 × 10 ⁴ Ω · cm or more. When the resin layer has a resistance value within the above range, the toner can be preferably charged under high temperature and high humidity conditions, and a uniform image can be obtained.

When the resin layer deviates from the resistance value within the above range, the effect of providing the resin layer, that is, the effect of uniformly charging the toner under the high temperature and high humidity condition is not suitably exhibited, which is preferable. Absent.

The resistance value of the resin layer was measured as follows.

(Measurement of volume resistance) P having a thickness of 100 μm
Forming a coating layer having a thickness of 7 to 20 μm on the ET sheet,
Based on ASTM standard (D-991-82) and Japan Rubber Association standard SRIS (2301-1969),
The voltage was measured by using a voltage drop type digital ohmmeter (manufactured by Kawaguchi Denki Seisakusho) provided with electrodes having a four-terminal structure for measuring the volume resistance of conductive rubber and plastic. Measurement environment is 20 ~
It was set to 25 ° C. and 50 to 60 RH%.

Although the present inventors have confirmed that the resin layer having a high resistance has an effect up to about 10 ¹⁶ Ω · cm, in the case of a material having a higher resistance than this, detection by the measuring device is performed. There are problems such as limitations, so we have not yet examined it. However, in the present invention, even when a material having a resistance higher than this is used, it is considered that the same effect can be obtained in comparison.

7) Film Thickness In the present invention, the film thickness of the resin layer on the regulating member is 5 μm.
It is preferably 50 μm or more and less than 50 μm. With the above-specified resin layer film thickness, the charge amount of the toner can be maintained in a suitable range in any environment.

When the resin layer film thickness is less than 5 μm,
Under high-temperature and high-humidity conditions, charge leakage causes variations in the charge amount of toner particles, resulting in poor uniformity of the initial image. On the other hand, when the thickness of the resin layer exceeds 50 μm, the charge-up of the toner, which occurs under low temperature and low humidity conditions, cannot be moderated gently, which causes image streaks, which is not preferable.

The film thickness measuring method of the present invention can be measured by a contact type film thickness meter. Further, a method of measuring by cross-section observation may be used.

In the toner used in the present invention, it is essential to use a polyester compound as a binder resin as a main constituent component of all binders. Specifically, when the content of the polyester compound in the binder resin component is 50% by mass or more, the toner has favorable charging characteristics and excellent image density stability. Further, when the ratio of the polyester compound is 80% by mass or more, the charging property of the toner becomes more preferable, so that the image density stability increases even in long-term use.

As the polyester compound used,
It is preferable to use a polyester resin obtained by polycondensing a polyhydric alcohol component and a polyvalent carboxylic acid component.

Among the polyhydric alcohol components, examples of the dihydric alcohol component include polyoxypropylene (2,
2) -2,2-bis (4-hydroxyphenyl) propane, polyoxypropylene (3,3) -2,2-bis (4-hydroxyphenyl) propane, polyoxypropylene (6) -2,2-bis (4-hydroxyphenyl) propane, polyoxyethylene (2,0) -2,2
Bisphenol A alkylene oxide adduct such as bis (4-hydroxyphenyl) propane, ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, neopentyl Glycol, 1,4-butenediol, 1,5-pentanediol, 1,6-hexanediol, 1,4-cyclohexanedimethanol, dipropylene glycol, polyethylene glycol, polytetramethylene glycol, bisphenol A, hydrogenated bisphenol A Etc.

Examples of trihydric or higher alcohol components include sorbitol, 1,2,3,6-hexanetetrol, 1,4-sorbitan, pentaerythritol, dipentaerythritol, tripentaerythritol, 1,
2,4-butanetriol, 1,2,5-pentanetriol, glycerol, 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, trimethylolpropane, 1,3.
5-trihydroxymethylbenzene etc. are mentioned.

Examples of the divalent carboxylic acid component among the polyvalent carboxylic acid components include maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, phthalic acid, isophthalic acid, terephthalic acid, cyclohexanedicarboxylic acid. , Succinic acid, adipic acid, sebacic acid, azelaic acid, malonic acid, n-dodecenylsuccinic acid, isododecenylsuccinic acid, n-dodecylsuccinic acid, isododecylsuccinic acid, n-octenylsuccinic acid, isooctenylsuccinic acid, n- Examples thereof include octyl succinic acid, isooctyl succinic acid, and anhydrides or lower alkyl esters of these acids.

Examples of the trivalent or higher carboxylic acid component include 1,2,4-benzenetricarboxylic acid (trimellitic acid), 1,2,5-benzenetricarboxylic acid, and 2,
5,7-naphthalene tricarboxylic acid, 1,2,4-naphthalene tricarboxylic acid, 1,2,4-butane tricarboxylic acid, 1,2,5-hexane tricarboxylic acid, 1,3-
Dicarboxyl-2-methyl-2-methylenecarboxypropane, 1,2,4-cyclohexanetricarboxylic acid, tetra (methylenecarboxyl) methane, 1,2,
7,8-octanetetracarboxylic acid, pyromellitic acid,
Examples thereof include empol trimer acids, anhydrides of these acids, and lower alkyl esters.

The toner of the present invention contains a colorant for imparting coloring power. The organic pigments or dyes preferably used in the present invention include the following.

As an organic pigment or an organic dye as a cyan colorant, a copper phthalocyanine compound and its derivative, an anthraquinone compound, a basic dye lake compound and the like can be used. Specifically, C.I. I. Pigment Blue 1, C.I. I. Pigment Blue 7, C.I. I. Pigment Blue 15, C.I. I. Pigment Blue 15: 1, C.I.
I. Pigment Blue 15: 2, C.I. I. Pigment Blue 15: 3, C.I. I. Pigment Blue 15: 4
C. I. Pigment Blue 60, C.I. I. Pigment Blue 62, C.I. I. Pigment Blue 66 and the like.

Organic pigments or organic dyes as magenta colorants include condensed azo compounds, diketopyrrolopyrrole compounds, anthraquinones, quinacridone compounds, basic dye lake compounds, naphthol compounds, benzimidazolone compounds, thioindigo compounds, perylene compounds. Is used. Specifically, C.I. I. Pigment Red 2,
C. I. Pigment Red 3, C.I. I. Pigment Red 5, C.I. I. Pigment Red 6, C.I. I. Pigment Red 7, C.I. I. Pigment Violet 19,
C. I. Pigment Red 23, C.I. I. Pigment Red 48: 2, C.I. I. Pigment Red 48: 3
C. I. Pigment Red 48: 4, C.I. I. Pigment Red 57: 1, C.I. I. Pigment Red 81:
1, C.I. I. Pigment Red 122, C.I. I. Pigment Red 144, C.I. I. Pigment Red 146,
C. I. Pigment Red 166, C.I. I. Pigment Red 169, C.I. I. Pigment Red 177, C.I.
I. Pigment Red 184, C.I. I. Pigment Red 185, C.I. I. Pigment Red 202, C.I. I.
Pigment Red 206, C.I. I. Pigment Red 2
20, C.I. I. Pigment Red 221, C.I. I. Pigment Red 254 and the like.

As the organic pigment or organic dye as the yellow colorant, compounds represented by condensed azo compounds, isoindolinone compounds, anthraquinone compounds, azo metal complexes, methine compounds and allylamide compounds are used. Specifically, C.I. I. Pigment Yellow 12,
C. I. Pigment Yellow 13, C.I. I. Pigment Yellow 14, C.I. I. Pigment Yellow 15, C.I.
I. Pigment Yellow 17, C.I. I. Pigment Yellow 62, C.I. I. Pigment Yellow 74, C.I. I.
Pigment Yellow 83, C.I. I. Pigment Yellow 93, C.I. I. Pigment Yellow 94, C.I. I. Pigment Yellow 95, C.I. I. Pigment Yellow 9
7, C.I. I. Pigment Yellow 109, C.I. I. Pigment Yellow 110, C.I. I. Pigment Yellow 1
11, C.I. I. Pigment Yellow 120, C.I. I. Pigment Yellow 127, C.I. I. Pigment Yellow 128, C.I. I. Pigment Yellow 129, C.I. I.
Pigment Yellow 147, C.I. I. Pigment Yellow 151, C.I. I. Pigment Yellow 154, C.I.
I. Pigment Yellow 168, C.I. I. Pigment Yellow 174, C.I. I. Pigment Yellow 175,
C. I. Pigment Yellow 176, C.I. I. Pigment Yellow 180, C.I. I. Pigment Yellow 18
1, C.I. I. Pigment Yellow 191, C.I. I. Pigment Yellow 194 and the like.

As the black colorant, carbon black,
A color tone adjusted to black using the yellow / magenta / cyan colorant is used.

These colorants may be used alone or in combination, and may be used in the form of a solid solution. The colorant used in the toner of the present invention includes hue angle, saturation, lightness, light resistance,
It is selected from the viewpoints of OHP transparency and dispersibility in toner.

The colorant is added in an amount of 1 to 20 parts by mass based on 100 parts by mass of the binder resin.

A low melting point compound, so-called wax, can be added to the toner in the present invention, if necessary.

Examples of waxes usable in the toner according to the present invention include petroleum waxes such as paraffin wax, microcrystalline wax, petroleum lactam and derivatives thereof, montan wax and derivatives thereof, hydrocarbon wax by Fischer-Tropsch method and the wax thereof. Derivatives, polyolefin waxes represented by polyethylene and polypropylene and their derivatives, natural waxes such as carnauba wax and candelilla wax and their derivatives, which are oxides, block copolymers with vinyl monomers, and graft modified products. including. Moreover,
Higher aliphatic alcohols, fatty acids such as stearic acid and palmitic acid, or compounds thereof, acid amide wax, ester wax, ketone, hydrogenated castor oil and its derivatives, plant wax, animal wax and the like can also be used.

In the toner relating to the image forming method of the present invention, the content of these wax components is preferably less than 20% by mass, and more preferably less than 10% by mass with respect to the toner. That is. If the wax component content exceeds 20% by mass, GP
This is not preferable because the effect of defining the peak top position in C measurement cannot be exhibited properly. Further, when toner particles are obtained by a pulverization method, if an excessive amount of wax is contained, the pulverizability becomes poor, and it becomes difficult to manufacture the toner.

The toner relating to the image forming method of the present invention may be blended with a charge control agent in order to stabilize the charging characteristics. Known charge control agents can be used,
In particular, a charge control agent having a high charging speed and capable of stably maintaining a constant charge amount is preferable.

Specific compounds include, as negative charge control agents, metal compounds of aromatic carboxylic acids such as salicylic acid, alkylsalicylic acid, dialkylsalicylic acid, naphthoic acid and dicarboxylic acids, metal salts of azo dyes or azo pigments or metals. Examples thereof include a complex, a polymer type compound having a sulfonic acid or carboxylic acid group as a side chain, a boron compound, a urea compound, a silicon compound, and calixarene. Examples of the positive charge control agent include a quaternary ammonium salt, a polymer type compound having the quaternary ammonium salt in the side chain, a guanidine compound, a nigrosine compound, an imidazole compound, and the like.

The charge control agent is preferably used in an amount of 0.5 to 10 parts by mass with respect to 100 parts by mass of the resin. However, in the toner relating to the image forming method of the present invention, it is not essential to add the charge control agent, and it is not always necessary to positively utilize the triboelectric charge between the toner layer thickness regulating member and the developer carrying member. It is not necessary to include a charge control agent.

In the present invention, a resin other than the polyester resin may be added in a small amount in the case where the effects described in the present invention are not impaired. For example, epoxy resin, styrene resin, acrylic resin, olefin resin, diene resin, polyamide resin, silicone resin, phenol resin, petroleum resin, urethane resin, etc. may be mentioned.

When using these resins, it is necessary to pay attention to the compatibility with the polyester resin. In order to improve the compatibility, those having various functional groups introduced at the polymer terminals can be preferably used. The addition amount of these resins is preferably less than 15% by mass with respect to the mass of the toner.

In the present invention, the glass transition temperature (Tg) of the toner particles is preferably 50 to 65 ° C. T
When g is less than 50 ° C, problems tend to occur from the viewpoint of storage stability and durability stability of the toner, and when it exceeds 65 ° C, the fixing point of the toner is increased. Particularly in the case of color toner for forming a full-color image, the color reproducibility at the time of fixing each color toner is lowered and the color reproducibility is slightly inferior.
The transparency of the OHP image is reduced.

In the present invention, for the Tg measurement, for example, "DSC-7" manufactured by Perkin Elmer Co. is used. The melting point of indium and zinc is used to correct the temperature of the device detection unit, and the heat of fusion of indium is used to correct the amount of heat. An aluminum pan was used as a sample and an empty pan was set as a control, and the temperature rising rate was 10 ° C./min. Measure with.

In the toner of the present invention, it is possible to add organic or inorganic fine particles which are generally widely known as external additives. Specifically, examples of the inorganic fine particles include metal oxides (aluminum oxide, titanium oxide,
Strontium titanate, cerium oxide, magnesium oxide, chromium oxide, tin oxide, zinc oxide, etc.), nitrides (silicon nitride, etc.), carbides (silicon carbide, etc.), metal salts (calcium sulfate, barium sulfate, calcium carbonate, etc.), Fatty acid metal salts (zinc stearate, calcium stearate, etc.), carbon black, silica and the like can be used. Examples of the organic fine particles include styrene, acrylic acid, methyl methacrylate, butyl acrylate, obtained by emulsion polymerization or spray drying.
A homopolymer or copolymer of a monomer component used in a binder resin for toner such as 2-ethylhexyl acrylate can be used. Moreover, it is also possible to use a plurality of types of these fine particles in combination, if necessary.

These fine particles are contained in an amount of 0.1 to 0.1 with respect to the toner.
With the addition amount of 3.0% by mass, it can be used without hindering various effects described in the present invention.

The method for producing the toner according to the present invention is not particularly limited, and the toner constituent materials such as the colorant and the charge control agent are uniformly mixed with the binder, melt-kneaded, and the obtained kneaded product is cooled and then jet-milled. A so-called pulverization method in which a fluidity modifier and the like are externally added can be used.

As another method, a wet process is used in which a colorant, a charge control agent, etc. are mixed and dispersed in a solution consisting of a solvent and a binder, and then the solution is introduced into a water system to suspend or coarsely emulsify and to perform classification drying. Tonerizing techniques can be used.

In the present invention, particularly when the polyester resin contains an ionic group, the polyester resin exhibits water dispersibility (self-emulsifying property). In this case, it is possible to exemplify a method in which a polyester resin is emulsified and dispersed in an aqueous system, and the polyester resin fine particles contained in the obtained dispersion are slowly aggregated to grow the coalescence into a size suitable for the toner to obtain the toner.

The polyester resin is dissolved in a water-soluble solvent such as ketones, alcohols, tetrahydrofuran, cellosolves, dioxane, etc., water is added, and the solvent is removed by azeotropic distillation to give an aqueous dispersion of the polyester resin. Obtainable. Slow coagulation can be achieved by adding an appropriate amount of electrolyte into the water dispersion system and controlling the temperature. In particular, a method of adding an amino group-containing ester consisting of amino alcohols and carboxylic acids, and hydrolyzing the ester in the system by raising the temperature, adjusting the pH, or the like to produce an amine salt of a carboxylic acid leads to a slow aggregation region. Preferred as a method. Particles containing a pigment (carbon black) can be produced if water-dispersed fine particles such as a pigment and carbon black coexist in the slow aggregation region. Further, it is possible to obtain toner particles colored with a dye by allowing a dye to coexist at the time of emulsification, and it is also possible to post-color the colorless particles obtained by a high temperature dispersion dyeing method.

As the toner particles according to the present invention, surface-modified particles can be used.

Particularly, when the toner particles are obtained by a pulverization method, the surface modification effect is suitably exhibited, which is preferable.

As an apparatus for surface modification treatment, a high-speed air impact method such as a hybridization system (manufactured by Nara Machinery Co., Ltd.), a klyptron system (manufactured by Kawasaki Heavy Industries, Ltd.), an inomizer system (manufactured by Hosokawa Micron Co., Ltd.), etc. Surface reformer applying MechanoFusion Systel (manufactured by Hosokawa Micron), MechanoMill (manufactured by Okada Seiko Co., Ltd.), etc., surface modifier applied by dry mechanochemical method, Tispercoat (manufactured by Nisshin Engineering Co., Ltd.), Momentary heat treatment for instantaneous heat treatment of toner particles such as surface reforming equipment applying wet coating method such as Coatmizer (made by Freund Industrial Co., Ltd.) and surffusion system (made by Nippon Pneumatic Mfg. Co., Ltd.) The devices can be used alone or in combination as appropriate.

As a method for adjusting the glass transition temperature of the polyester resin, the main peak position in the GPC measurement of the toluene soluble component, and the content of the toluene insoluble component of the polyester resin, the types of raw material acid components and alcohol components and combinations thereof are used. On the other hand, it can be achieved by appropriately adjusting the temperature, pressure and reaction time during the condensation reaction, the type and amount of the catalyst used, the timing of addition of various raw materials, the addition speed and the like.

As a method for adjusting the glass transition temperature of the toner, the main peak position in the GPC measurement of the toluene-soluble component, and the content of the toluene-insoluble component in the toner, a resin is used in addition to the method using the polyester resin described above. A method of separately adding a gel-containing polymer during melt-kneading and a method of separately adding compounds such as various metal complexes that cause crosslinking during kneading are preferably used.

As a method of adjusting the water content of the toner, there is a method of producing the toner by using a polyester resin having a suitable acid value. Here, the acid value of the polyester resin is determined by the following method.

200 to 300 ml of 2 to 10 g of sample
Weigh in an Erlenmeyer flask and methanol: toluene = 3
The resin is dissolved by adding about 50 ml of a mixed solvent of 0:70. If the solubility seems to be poor, a small amount of acetone may be added. Pre-standardized N / using a mixed indicator of 0.1% bromthymol blue and phenol red
Titrate with 10 potassium hydroxide / ethyl alcohol solution, and calculate the acid value from the consumption amount of the potassium hydroxide solution by the following calculation. Acid value = KOH (ml number) × f × 5.61 / sample mass (where f is a factor of N / 10KOH)

The acid value can be adjusted by adjusting the types and ratios of the acid component and the alcohol component constituting the polyester resin.

As other means for adjusting the water content of the toner, a method of adjusting the average particle diameter of the toner particles; a method of adjusting the surface properties of the toner particles by various surface modification treatment devices; A method of adjusting the addition amount, type, surface area, type and treatment amount of various surface treating agents to be used can also be suitably used.

Next, an image forming method of the present invention and an image forming apparatus for carrying out the method will be described with reference to the drawings.

An elastic roller is used as the toner carrier,
A method may be used in which the surface of the elastic roller or the like is coated with toner and the surface of the photosensitive member is brought into contact with the toner. In this case, development is performed by an electric field acting between the photoconductor and the elastic roller facing the photoconductor surface via the toner. Therefore, it is necessary that the surface of the elastic roller or the vicinity of the surface has an electric potential, and the electric field is present in a narrow gap between the surface of the photoconductor and the surface of the toner carrier. Therefore, it is possible to use a method in which the elastic rubber of the elastic roller is resistance-controlled in a medium resistance region to prevent electric conduction with the surface of the photoconductor and maintain an electric field, or a thin insulating layer is provided on the surface layer of the conductive roller. . Further, it is possible to adopt a configuration in which a conductive resin sleeve in which the side facing the surface of the photoconductor is coated with an insulating material is provided on the conductive roller, or a conductive layer is provided on the side not facing the photoconductor with the insulating sleeve. . Also,
It is also possible to use a rigid roller as the toner carrier and make the photoconductor flexible such as a belt. The roller as a toner carrier has a resistance value of 10 ² to 10 ⁹
The range of Ω · cm is preferable.

If the surface roughness Ra (μm) of the toner carrier is set to be 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.
When the surface roughness Ra of the toner carrier exceeds 3.0, not only is it difficult to thin the toner layer on the toner carrier, but also the chargeability of the toner is not improved, so that improvement in image quality cannot be expected. . When it is 3.0 or less, the toner carrying ability on the surface of the toner carrier is suppressed, the toner layer on the toner carrier is thinned, and the number of times 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, the surface roughness Ra is 0.2
If it is smaller than this, 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 "JISB 0601" and is based on a surface roughness measuring device ("Surfcoder S" manufactured by Kosaka Laboratory Ltd.).
E-30H "). Specifically, a 2.5 mm portion having a measurement length a in the direction of the center line is extracted from the roughness curve, the center line of this extracted portion is the X axis, the direction of longitudinal magnification is the Y axis, and the roughness curve is When represented by y = f (x), the value obtained by the following equation is expressed in micrometers (μm).

[0092]

[Equation 1]

In the image forming method of the present invention, the toner carrier may rotate in the same direction as the peripheral speed of the photoconductor,
It may rotate in the opposite direction. When the rotation is in the same direction, the peripheral speed of the toner carrier is 1.0 with respect to the peripheral speed of the photoconductor.
It is preferable to set it to be 5 to 3.0 times.

If the peripheral speed of the toner carrying member is less than 1.05 times the peripheral speed of the photosensitive member, the stirring effect of the toner on the photosensitive member is insufficient, and good image quality cannot be expected.
If the peripheral speed ratio exceeds 3.0, deterioration of the toner due to mechanical stress and toner sticking to the toner carrier occur and are promoted, which is not preferable.

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

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 an apparatus for carrying out the image forming method of the present invention. In FIG. 2, reference numeral 10 is a primary charging member that is in direct contact with the photosensitive drum 1 to perform direct charging. Rollers 11 to 13 are bias power sources, 15 is a transfer material such as paper, 16 is a transfer member, 17 is a fixing pressure roller, 18 is a fixing heating roller, and 19 is a cleaner. The same reference numerals are attached.

A bias power source 11 is connected to the charging roller 10 so as to uniformly charge the surface of the photosensitive drum 1. The developing device 7 accommodates the toner 4 in a toner container 5 and includes a developing roller 2 that is a toner carrier that rotates in the arrow direction. Further, the elastic regulating blade 3 and the toner 4, which are toner regulating members for regulating the toner and imparting the electric charge, are attached to the developing roller 2 and rotated in the arrow direction in order to impart the electric charge to the toner by friction with the developing roller 2. A coating 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 coating roller 9, and a voltage is applied to the negative side of the developing bias when the negative charging toner is used, and to the positive side of the developing bias when the positive charging toner is used. 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 its surface is preferably used. The hardness of the material of the elastic layer used for the elastic roller is 3
Those having 0 to 60 degrees (asker-C / load of 1 kg) are preferably used.

Further, the resistance of the developing roller 2 is preferably in the range of about 10 ² to 10 ⁹ Ωcm in terms of volume resistance value.
If it is lower than 10 ² Ωcm, for example, if there is a pinhole or the like on the surface of the photosensitive drum 1, an overcurrent may flow. On the other hand, when it is higher than 10 ⁹ Ωcm, toner charge-up due to triboelectric charging is apt to occur and the image density is apt to be lowered.

The toner coating amount is controlled by the elasticity regulating blade 3, which is in contact with the developing roller 2 via the toner layer. The contact pressure between the regulation blade 3 and the developing roller 2 at this time is 0.05 N / cm or more and 0.5 N / c or more as a linear pressure in the generatrix direction of the developing roller 2.
m or less is a preferable range.

The linear pressure is a load applied per length of the blade 3. For example, a load of 1.2 N is applied to the blade 3 having a contact length of 1 m to bring it into contact with the developing roller 2. In that case, the linear pressure is 1.2 N / m. 0.
If it is less than 05 N / cm, uniform triboelectric charging becomes difficult in addition to the control of the toner coat amount, which causes deterioration of fog. On the other hand, if it is higher than 0.5 N / cm, the toner particles are excessively loaded, and the deformation of the particles and the fusion of the toner to the regulation blade 3 or the developing roller 2 are likely to occur, which is not preferable.

The free end portion of the elastic regulating blade 3 may have any shape. For example, in addition to a straight sectional shape, an L-shaped portion that is bent near the tip, or a sphere that bulges near the tip is provided. A shape or the like is preferably used.

As the toner regulating member, it is preferable to use a metal elastic body such as stainless steel, steel or phosphor bronze as a base material, and to which a resin is adhered or coated on a portion corresponding to a sleeve contact portion.

Further, 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 effect on the toner, and a sufficient image density is obtained. Can be achieved and good quality images 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 the present example, the primary charging member is a charging roller 10 having a central core metal 10b and a conductive elastic layer 10a forming the outer periphery thereof as a basic configuration. The charging roller 10 is brought into contact with one surface of the photosensitive drum 1, which is an electrostatic latent image carrier, with a suppression force, and is driven to rotate as the photosensitive drum 1 rotates.

A preferable process condition when the charging roller 10 is used is that the contact pressure of the roller is 0.05 to 5 N /
The applied voltage may be a DC voltage or a DC voltage superimposed with an AC voltage, and is not particularly limited. However, when a DC voltage superimposed with an AC voltage is used, the AC voltage is 0.5. ~ 5dVpp, AC frequency = 5
0 Hz to 5 kHz, DC voltage = ± 0.2 to ± 1.5 kV
Therefore, when a DC voltage is used, the DC voltage = ± 0.2
Is ± 5 kV. In the present invention, the applied voltage of only the 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 becomes unnecessary and ozone generation is reduced as compared with non-contact corona charging. As a material of the charging roller and the charging blade as the contact charging means, conductive rubber is preferable, and a releasing film may be provided on the surface thereof.
As the releasable coating, nylon resin, PVDF (polyvinylidene fluoride), PVDC (polyvinylidene chloride)
Are applicable.

After the step of charging the electrostatic latent image carrier, an electrostatic latent image corresponding to an information signal is formed on the photosensitive drum 1 by, for example, exposure 14 from the light emitting element, and the developing roller 2
The toner develops the electrostatic latent image into a visible image at a position where the electrostatic latent image comes into contact with. Further, in the image forming method of the present invention, particularly by combining with a developing system in which a digital latent image is formed on the photosensitive drum 1, it is possible to faithfully develop a dot latent image without disturbing the latent image. Becomes The visible image is transferred to the transfer material 15 by the transfer member 16 and passes between the heating roller 18 and the pressure roller 17 to be fixed to obtain a permanent image. The heating / pressurizing fixing means is basically a heating roller 18 having a built-in heating element such as a halogen heater and an elastic pressing roller 17 pressed against the heating roller 18 as a basic structure. In addition, a method of heating and fixing 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 which is in contact with the surface of the photosensitive drum 1, and the photosensitive drum 1 is cleaned. It

FIG. 3 is a schematic block diagram of an example of an image forming apparatus for collectively transferring multiple toner images onto a recording material by using an intermediate transfer member in the image forming method of the present invention.

In FIG. 3, 7a to 7d are developing devices for respective colors of black, yellow, magenta, and cyan, 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. An intermediate transfer drum, which is a body, 25a is a conductive support, 25b is an elastic layer,
Reference numeral 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. 1 and 2 are denoted by the same reference numerals.

The rotatable charging roller 10 as a charging member, to which a charging bias voltage is applied, is brought into contact with the surface of the photosensitive drum 1 as the electrostatic latent image carrier to rotate the surface of the photosensitive drum 1. A first electrostatic latent image is formed on the photoconductor drum 1 by the laser light 22 emitted from the light source device 21 as the exposure means, which is uniformly primary charged.
The formed first electrostatic latent image is developed with the black toner in the black developing device 7a as the first developing device provided in the rotatable developing unit 24 to form a black toner image. The black toner image formed on the photoconductor drum 1 is electrostatically primarily transferred onto the intermediate transfer drum 25 by the action of the transfer bias voltage applied to the conductive support 25 a of the intermediate transfer drum 25.
Next, in the same manner as described above, a second electrostatic latent image is formed on the surface of the photosensitive drum 1, the developing unit 24 is rotated, and the second electrostatic latent image is formed.
Of the yellow developing device 7b as a developing device for developing the yellow toner image to form a yellow toner image, and the black toner image is primarily transferred to the intermediate transfer drum 25.
The yellow toner image is electrostatically primary-transferred thereon. Similarly, the developing unit 24 is rotated to generate the third electrostatic latent image and the fourth electrostatic latent image, and the magenta toner in the magenta developing device 7c as the third developing device and the fourth developing device are used as the fourth developing device. The cyan toner in the cyan developing device 7d performs sequential development and primary transfer, and the toner images of the respective colors are primarily transferred onto the intermediate transfer drum 25. Intermediate transfer drum 2
The multiple toner image primarily transferred onto the transfer material 5 is electrostatically and collectively transferred onto the transfer material 15 by the operation of the transfer bias voltage from the secondary transfer device 28 located on the opposite side through the transfer material 15. Next is transcribed. The multiple toner image secondarily transferred onto the transfer material 15 is heat-fixed on 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 the cleaner 19 having a cleaning blade that contacts the surface of the photosensitive drum 1, and the photosensitive drum 1 is cleaned.

The primary transfer from the photoconductor drum 1 to the intermediate transfer drum 25 is performed by the intermediate transfer drum 2 as a primary transfer device.
A transfer current is obtained by applying a bias from the bias power supply 26 to the conductive support 25a of No. 5 to transfer the toner image.

The intermediate transfer drum 25 comprises a conductive support 25a which is a rigid body, and an elastic layer 25b which covers the surface. As the conductive support 25a, a metal or alloy such as aluminum, iron, copper and stainless, and a conductive resin in which carbon or metal particles are dispersed can be used, and the shape thereof is cylindrical or cylindrical. Examples thereof include those having a shaft penetrating through the center and those having reinforcement inside the cylinder.

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 (NB
R), chloroprene rubber, butyl rubber, silicone rubber, fluorine rubber, nitrile rubber, urethane rubber, acrylic rubber, epichlorohydrin rubber, norbornene rubber, and other elastomer rubbers are preferably used. A resin such as a polyolefin resin, a silicone resin, a fluorine resin, a polycarbonate, or a copolymer or 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, graphite or fluorocarbons obtained by binding fluorine to graphite and polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), ethylene-tetrafluoroethylene. Copolymer (ETFE)
And fluorine compounds such as tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), silicone-based particles such as silicone resin particles, silicone rubber and silicone elastomer, polyethylene (P
E), polypropylene (PP), polystyrene (P
S), acrylic resin, polyamide resin, phenol resin, epoxy resin and the like are preferably used.

A conductive agent may be added to the binder of the surface layer in order to control the resistance. Examples of the conductive agent include various conductive inorganic particles and carbon black, ionic conductive agents, conductive resins and conductive particle dispersed resins.

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

The fixing device 23 is replaced by a heat roller fixing device having a heating roller 18 and a pressure roller 17, and the film in contact with the toner image on the transfer material 15 is heated, thereby the toner image on the transfer material 15 is heated. And transfer material 15
It is also possible to use a film heat fixing device that heat-fixes the multiple toner images.

Instead of the intermediate transfer drum 25 as an intermediate transfer member used in the image forming apparatus shown in FIG. 3, an intermediate transfer belt may be used to collectively transfer multiple toner particles onto a recording material. FIG. 4 shows a schematic configuration diagram of an apparatus using the intermediate transfer belt.

In FIG. 4, 30 is an intermediate transfer belt, and 3 is
1 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 sources, 39 is a charging member for cleaning, and FIG. -The same code | symbol is attached | subjected to the same member as FIG.

In the structure of FIG. 4, the toner image formed and carried on the photosensitive drum 1 passes from the primary transfer roller 32 to the intermediate transfer belt while passing through the nip portion between the photosensitive drum 1 and the intermediate transfer belt 30. By the electric field formed by the primary transfer bias applied to 30, the primary transfer is sequentially performed on the outer peripheral surface of the intermediate transfer belt 30.

The primary transfer bias for sequentially superposing and transferring the toner images of the first to fourth colors from the photosensitive drum 1 to the intermediate transfer belt 30 has the opposite polarity to the toner and is applied from the bias power source 34.

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

Reference numeral 33b denotes a secondary transfer roller, which corresponds to the secondary transfer counter roller 33a and is supported in parallel to the lower surface of the intermediate transfer belt 30 so as to be separated therefrom.

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

After the transfer of the image to the transfer material 15, the cleaning charging member 39 is brought into contact with the intermediate transfer belt 30, and a bias having a reverse polarity to that of the photosensitive drum 1 is applied from the bias power source 35 to transfer the image. Toner remaining on the intermediate transfer belt 30 without being transferred to the material 15 (transfer residual toner) is charged with an electric charge having a polarity opposite to that of the photosensitive drum 1. Next, the transfer residual toner is transferred to the photosensitive drum 1 in 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 comprises 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.

For the base layer and the surface treatment layer, rubber, elastomer or resin can be used. 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, fluororubber, polysulfide rubber, polynorbornene rubber, hydrogenated nitrile rubber and thermoplastic elastomer (for example, polystyrene type, polyolefin type,
One kind or two or more kinds selected from the group consisting of polyvinyl chloride type, polyurethane type, polyamide type, polyester type, fluororesin type and the like) can be used. However, the material is not limited to the above materials. Also,
As the resin, a resin such as a polyolefin resin, a silicone resin, a fluorine resin, or a polycarbonate can be used. You may use the copolymer or mixture of these resins.

As the base layer, the above-mentioned rubber, elastomer,
The resin can be used in the form of a film. Also,
A woven fabric-shaped, non-woven fabric-shaped, thread-shaped, or film-shaped core body layer may be coated with, dipped, or sprayed with the above-mentioned rubber, elastomer, or resin.

The material forming the core layer is, for example, cotton, silk,
Intangible fibers such as hemp and wool; regenerated fibers such as chitin fibers, alginate fibers and regenerated cellulose fibers; semi-synthetic fibers such as acetate fibers; polyester fibers, nylon fibers,
Synthetic fibers such as acrylic fiber, polyolefin fiber, polyvinyl alcohol fiber, polyvinyl chloride fiber, polyvinylidene chloride fiber, polyurethane fiber, polyalkylparaoxybenzoate fiber, polyacetal fiber, aramid fiber, polyfluoroethylene fiber and phenol fiber;
One or more selected from the group consisting of inorganic fibers such as carbon 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 low resistance value of the intermediate transfer belt 30. Although the conductive agent is not particularly limited, for example, carbon, metal powders such as aluminum and nickel, metal oxides such as titanium oxide, and quaternary ammonium salt-containing polymethylmethacrylate, polyvinylaniline, polyvinylpyrrole, One or more selected from the group consisting of conductive polymer compounds such as polydiacetylene, polyethyleneimine, boron-containing polymer compounds and polypyrrole can be used. However, the conductive agent is not limited to the above.

Further, a lubricant may be added if necessary in order to improve 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, graphite and fluorocarbons obtained by binding fluorine to graphite, polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVD).
F), ethylene-tetrafluoroethylene copolymer (E
Fluorine compounds such as TFE) and tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), silicone compounds such as silicone resin, silicone rubber and silicone elastomer, polyethylene (P
E), polypropylene (PP), polystyrene (P
S), 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 respectively formed in a plurality of image forming sections and which are successively transferred onto 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 portions, 42a to 42d are latent image forming means, and 43a to 4d.
3d is a transfer discharge part, 44a to 44d are primary charging parts, 4
5 is a static eliminator, 46 is a conveyor belt, 7a to 7d are developing devices, 48 is an adsorption charger, 49a to 49d are separate static eliminators and discharge parts, and 50 is a discharge port. The same members as those in FIGS. Numbers are attached.

In the configuration of FIG. 5, first to fourth image forming portions 41a to 41d are arranged in parallel, and each image forming portion is a photosensitive drum 1a to 1 which is a dedicated electrostatic latent image carrier.
It has d. The photosensitive drums 1a to 1d are provided with latent image forming means 42a to 42d and developing devices 7a to 7 on the outer peripheral side thereof.
d, transfer discharge parts 43a to 43d, cleaner 19a to
19d and primary charging units 44a to 44d are arranged.

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

While the yellow image is being transferred onto the transfer material 15 as described above, a latent image of a magenta component color is formed on the photosensitive drum 1b in the second image forming section 41b, and then the developing device 7b is operated. It is a visible image with magenta toner.
This visible image (magenta toner image) is transferred onto a predetermined position of the transfer material 15 when the transfer material 15 which has been transferred by the first image forming section 41a is carried into the transfer discharge section 42b. To be done.

Thereafter, the third and fourth steps are performed by the same method as described above.
In the image forming portions 41c and 41d of the above, cyan and black images are formed, and the same transfer material 15 is formed.
Then, the cyan color and the black color are superimposed and transferred.
When such an image forming process is completed, the transfer material 15 is conveyed to the fixing device 23 and the image on the transfer material 15 is fixed. As a result, a multicolor image can be obtained on the transfer material 15. Each photoconductor drum 1a after the transfer is completed
The residual toner 1d is removed by the cleaners 19a to 19d and is used for the subsequent latent image formation.

In the image forming apparatus, the conveyor belt 46 is used to convey the transfer material 15, as shown in FIG.
In, the transfer material 5 is conveyed from the right side to the left side, and in the conveying process, the transfer material 5 passes through each of the transfer discharge sections 43a to 43d in each of the image forming sections 41a to 41d to be transferred.

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

When the transfer material 15 passes through the fourth image forming portion 41d, a DC voltage is applied to the static eliminator 45, and the transfer material 15 is transferred.
Is discharged from the conveyor belt 46, then enters the fixing device 23, the image is fixed, and the sheet is discharged from the discharge port 50.

In this apparatus, each of the plurality of image forming sections is provided with an independent electrostatic latent image bearing member, and the transfer material is a belt type conveying means, and the electrostatic latent image bearing members are sequentially transferred. The electrostatic latent image carrier, which is configured to be sent to the transfer unit, is provided in common with the image forming unit, and the transfer material is a drum type conveying unit, and the transfer unit of the electrostatic latent image carrier is used. May be repeatedly sent to each color to receive the transfer of each color.

In the conveyor belt system of FIG. 5, since the volume resistance is high, the conveyor belt increases the charge amount in the process of repeating 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, but the toner of the present invention has excellent transferability, and therefore even if the charge on the conveyor belt increases each time transfer is repeated. With the same transfer current, the transferability of toner in each transfer can be made uniform, and a high-quality image of high quality can be obtained.

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

In FIG. 6, 44 is a primary charging section, 60 is a transfer drum, 61 is a gripper, 62 is a transfer charger, and 6
3a and 63b are separation chargers, 64 is a separation guide,
The same members as those in FIGS. 1 to 5 are denoted by the same reference numerals.

In the structure shown in FIG. 6, the electrostatic latent image formed on the photosensitive drum 1 by an appropriate means has developing devices 7a to 7a mounted on the developing unit 24 which rotates in the direction of the arrow.
In the first developing device 7a in 7d, it is visualized by the toner. The color toner image on the photosensitive drum 1 is
It is transferred by the transfer charger 62 onto 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 the cleaner 19 having a cleaning blade that contacts the surface of the photosensitive drum 1, and the photosensitive drum 1 is cleaned.

A corona charger or a contact charger is used as the transfer charger 62. When a corona charger is used as the transfer charger 62, a voltage of −10 kV to +10 kV is applied and the transfer current is − It is 500 μA to +500 μA. A holding member is stretched on the outer peripheral surface of the transfer drum 60,
This holding member is composed of a film-like dielectric sheet such as a polyvinylidene fluoride resin film or polyethylene terephthalate. For example, a thickness of 100 μm to 20
A sheet having 0 μm and a volume resistance of 10 ¹² to 10 ¹⁴ Ω · cm is used.

Next, the developing unit 24 rotates for the second color, and the developing device 7b faces the photosensitive drum 1. Then, it is developed with the second toner in the developing device 7b, and this toner image is also transferred onto the same transfer material 15 as described above.

Further, the third and fourth colors are similarly processed. In this way, the transfer drum 60 is rotated a predetermined number of times while carrying the transfer material 15, and the toner images of a predetermined number of colors are transferred in multiple. The transfer current for electrostatic transfer is 1st color <2
It is preferable to increase the order of the color <third color <4th color in order to reduce the transfer residual toner remaining on the photosensitive drum 1.

The multi-transferred transfer material 15 is separated from the transfer drum 60 by the separation chargers 63a and 63b, is fixed by the heating / pressurizing roller fixing device 23, and is color-mixed at the time of fixing, whereby a full-color copy image is obtained. Becomes

FIG. 7 shows another example of an apparatus for carrying out the image forming method of the present invention, in which the four color toner images primarily transferred onto the intermediate transfer drum are secondarily transferred onto a transfer material at once. A schematic configuration diagram of an image forming apparatus using a transfer belt as a secondary transfer means is shown.

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

As the organic photosensitive layer, the photosensitive layer contains a charge generating substance and a substance having a charge transporting property in the same layer.
It may be a single layer type or a function-separated type photosensitive layer in which the charge transport layer contains a charge generation layer as a component. 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 of preferred examples.

Polycarbonate resin, polyester resin, and acrylic resin are particularly preferable as the binder resin of the organic photosensitive layer because of good transferability and cleaning property, poor cleaning, fusing of toner to the photoreceptor, and filming of external additives. Hard to happen.

In the charging step, there are a method of non-contact with the photosensitive drum 1 using a corona charger, and a contact type method using a roller or the like. In order to reduce the amount of ozone and generate ozone, a contact type as shown in FIG. 7 is preferably used.

The charging roller 10 has a basic core metal 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.

Preferable process conditions when the charging roller 10 is used are the same as those of the apparatus shown in 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 ± 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 of the photosensitive drum 1, and at the same peripheral speed as the photosensitive drum 1, the counterclockwise arrow. Rotate in the direction.

First formed and carried on the surface of the photosensitive drum 1.
Color toner images are transferred to the photosensitive drum 1 and 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 transfer nip area by the applied transfer bias to the intermediate transfer drum 25 while passing through the transfer nip portion where the and are in contact with each other.

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

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

When the transfer means is a transfer roller, the core metal at the center and the conductive elastic layer forming the outer periphery thereof are the basic components.

For the intermediate transfer drum and transfer roller,
Common materials can be used. 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 can be satisfactorily formed. It is possible to form a toner image and prevent the transfer material 15 from being wound around the intermediate transfer drum 25. Particularly, it is particularly preferable that the volume specific resistance value of the elastic layer 25b of the intermediate transfer drum 25 is 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
It 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 the range of 10 to 40 degrees, while the hardness of the elastic layer of the transfer roller is the intermediate transfer drum 25.
It is preferable that the elastic layer 25b is harder than the elastic layer 25b and has a value of 41 to 80 degrees in order to prevent the transfer material 15 from being wound around the intermediate transfer drum 25. When the hardness of the intermediate transfer drum 25 and the transfer roller are opposite, a recess is formed on the transfer roller side, and the transfer material 15 is likely to be wound around the intermediate transfer drum 25.

In FIG. 7, below the intermediate transfer drum 25,
A transfer belt 73 is arranged. The transfer belt 73 is
It is wound around two rollers, that is, a bias roller 74 and a tension roller 75, arranged in parallel to the axis of the intermediate transfer drum 25, and is driven by a driving means (not shown). The transfer belt 73 is a tension roller 75.
Since the bias roller 74 side is configured to be movable in the arrow direction with the side being the center, the intermediate transfer drum 25
Can be contacted and separated from below in the direction of the arrow. The bias roller 74 includes a bias power supply 76 for secondary transfer.
Is applied with a desired secondary transfer bias, while the tension roller 75 is grounded.

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

A tension of about 5% is applied to the transfer belt 73 by the bias roller 74 and the tension roller 75 described above.

The transfer belt 73 is rotated at a constant speed or a peripheral speed different from that of 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, the bias power source 76 applies a bias having a polarity opposite to that of the frictional charge of the toner to the transfer belt 73. The upper toner image is transferred to the surface side of the transfer material 15.

The same material as the charging roller can be used as the material of the transfer rotary member, and the contact pressure of the roller is 5 to 500 g / c as a preferable transfer process condition.
m, the DC voltage is ± 0.2 to ± 10 kV.

For example, the conductive elastic layer 74b of the bias roller 74 is made of polyurethane or ethylene-propylene-diene terpolymer (E) in which a conductive material such as carbon is dispersed.
It is made of an elastic body having a volume resistance of about 10 ⁶ to 10 ¹⁰ Ωcm such as PDM). A bias is applied to the cored bar 74a by a constant voltage bias power source. The bias condition is preferably ± 0.2 to ± 10 kV.

Next, the transfer material 15 is conveyed to a fixing device 23 having a heating roller 18 containing a heating element such as a halogen heater and an elastic pressure roller 17 pressed against the heating roller 18 as a basic structure. The toner image is transferred to the transfer material 1 by passing between the heating roller 18 and the pressure roller 17.
5 is fixed under heat and pressure. A method of fixing with a heater through a film may be used.

[0176]

EXAMPLES The present invention will be described in detail below, but the present invention is not limited thereto.

Polyester Resin Synthesis Example Various materials were weighed so as to have a molar ratio as shown in Table 1, placed in a 2-liter four-necked flask, and the four-necked flask was refluxed and separated with water. An apparatus, a nitrogen gas introducing pipe, a thermometer and a stirrer were attached, and nitrogen was introduced into the flask from the nitrogen gas introducing pipe and heated by a mantle heater while stirring and reacting them. The reaction temperature at this time is 180 ° C to 240 ° C.
Met. Then, the reaction state was traced while measuring the acid value during this reaction, and when the predetermined acid value was reached, each reaction was terminated to synthesize polyester resins (1) to (6). The reaction time at this time was 5 to 10 hours. The abbreviations in the table are as follows. EG: ethylene glycol PG: propylene glycol BPA-PO: polyoxypropylene (2,2) -2,
2-bis (4-hydroxyphenyl) propane BPA-EO: polyoxyethylene (2,2) -2,2
-Bis (4-hydroxyphenyl) propane TPA: terephthalic acid IPA: isophthalic acid FA: fumaric acid TMA: trimellitic acid

Table 1 shows the acid value, glass transition temperature and peak top molecular weight of the toluene usable component of the obtained polyester resin.

[0179]

[Table 1]

(Toner Production Example) Toner Production Example 1 (Binder resin) Polyester resin (1) 100 parts by mass (colorant) C.I. I. Pigment Blue 15: 3 8 parts by mass (charge control agent) Negative charge control agent (zinc compound of dialkyl salicylic acid) 5 parts by mass The above materials are sufficiently premixed by a Henschel mixer, and melt-kneaded by a twin-screw extruder, After cooling, it was roughly pulverized to about 1 to 2 mm using a hammer mill, and then finely pulverized by an air jet type fine pulverizer. Further, the obtained finely pulverized product was classified to obtain toner particles (1) having a weight average particle diameter of 8.1 μm.

To 100 parts by mass of the toner particles (1), B
1.2 parts by mass of hydrophobized silica fine particles having an ET value of 350 m ² / g, a primary particle size of 7 nm, and a primary particle size of 3
Toner (1) was obtained by adding 1.1 parts by mass of calcium titanate having a particle size of 60 nm and a secondary particle size of 1.9 μm and mixing them with a Henschel mixer (Mitsui Miike Kakoki Co., Ltd.).

Table 2 shows the physical properties of Toner (1).

Production Example 2 of Toner In addition to using polyester resin (2) as a binder resin and 8 parts by mass of an aluminum compound of 3,5-di-tert-butylbutylsalicylic acid as a charge control agent, Weight average particle size in the same manner as in Production Example 9.
1 μm toner particles (2) and toner (2) were obtained.

Table 2 shows the physical properties of Toner (2).

Toner Production Example 3 Toner particles (3) having a weight average particle diameter of 9.2 μm and toner (3) were produced in the same manner as in Toner Production Example 1 except that the polyester resin (3) was used as the binder resin. ) Got.

Table 2 shows the physical properties of Toner (3).

Toner Production Example 4 Polyester resin (4) was used as the binder resin, and C.I. I. Pigment Red 122 was used in the same manner as in Toner Production Example 1 to obtain toner particles (4) having a weight average particle diameter of 8.2 μm and toner (4).

Table 2 shows the physical properties of Toner (4).

Production Example 5 of Toner Aside from using polyester resin (5) as the binder resin and 5 parts by mass of the aluminum compound of 3,5-di-tert-butylbutylsalicylic acid as the charge control agent, Weight average particle size 1 in the same manner as in Production Example 1
Toner particles (5) of 0.5 μm were obtained.

100 parts by mass of the obtained toner particles (5) were mixed with 0.4 part by mass of hydrophobized titanium oxide fine particles having a BET value of 6 m ² / g and a primary particle size of 250 nm with a Henschel mixer. Toner (5) was obtained.

Table 2 shows the physical properties of Toner (5).

Toner Production Example 6 Toner particles (6) having a weight average particle diameter of 9.0 μm were obtained in the same manner as in Toner Production Example 1 except that the polyester resin (6) was used as the binder resin.

To 100 parts by mass of the obtained toner particles (6), 1.8 parts by mass of untreated silica fine particles having a BET value of 200 m ² / g and a primary particle size of 12 nm were added to a Henschel mixer (Mitsui Miike Kakoki ( Co., Ltd.) to obtain Toner (6).

Table 2 shows the physical properties of Toner (6).

Toner Production Example 7 Toner particles (7) having a weight average particle size of 10.7 μm were obtained by changing the pulverization conditions and classification conditions of Toner Production Example 1.

Toner (7) was obtained by stirring the toner particles (7) under the same conditions as in Production Example 1 using a Henschel mixer without adding fine powder.

Table 2 shows the physical properties of Toner (7).

[0198]

[Table 2]

<Example 1> Using the obtained toner (1), image evaluation was performed according to the following methods.

[0200]Image fog evaluation Using an image forming apparatus as shown in FIG. 8, high humidity and high humidity conditions
A4 CLC paper under (temperature 30 ℃, humidity 80% RH)
(Canon; 80 g / m²) Of image density 2%
Character images were continuously printed on 15,000 sheets. 1st, 5
Using the 0th, 5000th, and 15000th images
Image fogging was evaluated under high temperature and high humidity conditions. So
After that, the device was put under low temperature and low humidity conditions (temperature 15 ° C, humidity 1
0% RH) for 24 hours, and then A4 CL in the same environment
C paper (Canon; 80 g / m ²) Using image density
2% of the character image was continuously printed on 15,000 sheets. 1 sheet
The 50th, 5000th, and 15000th images
Image fog evaluation under low temperature and low humidity conditions
It was

The image forming apparatus will be described below.

FIG. 8 is a schematic view of a modified laser beam printer (“LBP-840” manufactured by Canon Inc.) which utilizes a non-magnetic one-component system contact development type electrophotographic process. In this example, an apparatus obtained by modifying the following parts (a) to (h) was used. The reference numerals in the figure are the same as those in FIGS. (A) Change the process speed to 135 mm / s. (B) The charging method of the apparatus was direct charging by contacting a rubber roller, and the applied voltage was a DC component (-1200V). (C) A medium resistance rubber roller (diameter 16 mm, hardness ASKER-C 45 degrees, resistance 1) made of a silicone rubber in which carbon black is dispersed is used as a toner carrier (developing roller) 2.
0 ⁵ Ω · cm) and abutted on the photoconductor drum 1. (D) The rotational peripheral speed of the toner bearing member was in the same direction at the contact portion with the photosensitive drum 1, and was driven so as to be 155% of the rotational peripheral speed of the photosensitive drum 1. (E) The photoconductor was changed to the following.

As the photosensitive drum 1 used here, Al
A cylinder was used as a base body, and layers having the following constitution were sequentially laminated by dip coating to prepare a photosensitive drum. (1) Conductive coating layer: Mainly composed of a powder of tin oxide and titanium oxide dispersed in a phenol resin. Film thickness 15μ
m. (2) Undercoat layer: Mainly composed of modified nylon and copolymer nylon. The film thickness is 0.6 μm. (3) Charge generation layer: Mainly composed of a butyral resin in which a titanyl phthalocyanine pigment having absorption in a long wavelength region is dispersed. The film thickness is 0.6 μm. (4) Charge transport layer: Mainly composed of a hole-transporting triphenylamine compound dissolved in a polycarbonate resin (molecular weight 20000 according to Ostwald viscosity method) at a mass ratio of 8:10. Film thickness 20 μm. (F) As a means for applying toner to the toner carrier, an application roller 9 made of urethane foam rubber is provided in the developing device 7 and brought into contact with the toner carrier. A voltage of about −550V is applied to the coating roller 9. (G) In order to control the coat layer of the toner on the toner carrier, a polyamide elastomer (resistance 1.0 × 10 ⁶ Ω.
cm, the saturated water absorption rate was 0.8% by mass, and the film thickness was 25 μm). (H) The applied voltage at the time of development was only the DC component (-450V).

The electrophotographic apparatus was modified and the process conditions were set as follows so as to be compatible with the modification of these process cartridges.

The modified device uses a roller charger (only DC is applied) and uses a photosensitive drum 1 which is an electrostatic latent image carrier.
To be uniformly charged. After charging, an electrostatic latent image is formed by exposing the image portion with a laser beam 22 to form a visible image with toner, and then the toner image is transferred to the transfer material 15 by the roller 16 to which a voltage of +700 V is applied. To have.

Regarding the charging potential of the photosensitive drum 1, the dark portion potential was set to -580V and the light portion potential was set to -150V.

The fog image was evaluated by the following method using the obtained image sample.

The fog on the paper was measured in the white solid part (the part where characters are not printed) of the image sample. Fog is measured by REFLECT MET manufactured by Tokyo Denshoku Co., Ltd.
It was measured using an ERMODEL TC-6DS.

The fog amount was calculated by the following formula. The smaller the number, the less fog. Fog amount (%) = (whiteness before printing)-(whiteness of non-image forming part (white background) of recording material after printing)

The fog was measured at arbitrary 5 points on one sample image, and the arithmetic mean value was used for evaluation based on the following criteria. a: Very good (less than 1.0%) b: Good (1.0% or more, less than 2.0%) c: Practical (2.0% or more, less than 3.0%) d: Somewhat problematic Yes, but practical (3.0% or more, 4.0
%) E: Not practical (4% or more)

The evaluation results are shown in Table 3.

Evaluation of Image Streaks Immediately after printing the sample images for the above-mentioned image fog evaluation (first sheet, 50th sheet, 5000th sheet, 15000th sheet in both environments), one halftone image was printed out. The halftone image printed immediately after the first sheet is referred to as the "first streak evaluation image", and the 50th, 5000th, and 15000th streak evaluation images are obtained in the same manner in both environments. It was

Using the obtained image for evaluation, evaluation was made based on the following criteria. a: Very good (no streak observed) b: Good (one or two thin streaks) c: Practical use (two or more thin streaks, but no problem for practical use) d : There is a problem in practical use (there is one dark streak) e: Practical use (there is a streak of d rank or higher)

The evaluation results are shown in Table 3.

<Examples 2 to 5> Images were evaluated in the same manner as in Example 1 except that the toners (2) to (5) shown in Table 2 were used instead of the toner (1).

The evaluation results are shown in Table 3.

<Example 6> The same procedure as in Example 1 was carried out except that the surface resin of the elasticity-regulating blade was replaced with polyamide elastomer and polypropylene (resistance 6.4 x 10 ¹⁵ Ωcm, film thickness 9 µm) was used. Image evaluation was performed.

The evaluation results are shown in Table 3.

<Comparative Example 1> Image evaluation was performed in the same manner as in Example 1 except that Toner (6) shown in Table 2 was used instead of Toner (1). Since the fusion was remarkable and it was virtually impossible to regulate the toner layer thickness, the image evaluation was stopped at the time when the first image was sampled under the low temperature and low humidity condition.

The evaluation results are shown in Table 3.

<Comparative Example 2> The toner (7) shown in Table 2 was used in place of the toner (1), and the image evaluation was performed in the same manner as in Example 1.

The evaluation results are shown in Table 3.

Comparative Example 3 Example 1 was repeated except that the surface resin of the elasticity regulating blade was replaced with polyamide elastomer to be a conductive urethane resin (resistance 2.0 × 10 ³ Ω · cm, film thickness 90 μm). Image evaluation was performed in the same manner as in.

The evaluation results are shown in Table 3.

[0225]

[Table 3]

(Production Example of Toner ) Production Example 8 of Toner (Binder Resin A) Polyester Resin (1) 95 Parts by Mass (Binder Resin B) Styrene / n-Butyl Acrylate Copolymer (Mass Ratio 90/10) (Mn = 33000 Mw / Mn = 3.0) 5 parts by mass (colorant) C.I. I. Pigment Blue 15: 3 10 parts by mass (charge control agent) Negative charge control agent (zinc compound of dialkyl salicylic acid) 5 parts by mass The above materials are sufficiently premixed by a Henschel mixer, and melt-kneaded by a twin-screw extruder, After cooling, it was roughly pulverized to about 1 to 2 mm using a hammer mill, and then finely pulverized by an air jet type fine pulverizer. Further, the obtained finely pulverized product was classified to obtain toner particles (8) having a weight average particle diameter of 9.1 μm.

To 100 parts by mass of this toner particle (8), B
Toner (8) was prepared by mixing 0.8 parts by mass of hydrophobized silica fine particles having an ET value of 110 m ² / g and a primary particle diameter of 20 nm with a Henschel mixer (Mitsui Miike Kakoki Co., Ltd.).
Got

Table 4 shows the physical properties of Toner (8).

Toner Production Example 9 A toner having a weight average particle diameter of 8.8 μm was prepared in the same manner as in Toner Production Example 8 except that the binder resin A was 65 parts by mass and the binder resin B was 35 parts by mass. Toner particles (9) and toner (9) were obtained.

Table 4 shows the physical properties of Toner (9).

Toner Production Example 10 A toner having a weight average particle diameter of 9.0 μm was prepared in the same manner as in Toner Production Example 8 except that the binder resin A was 25 parts by mass and the binder resin B was 75 parts by mass. Toner particles (10) and toner (10) were obtained.

Table 4 shows the physical properties of Toner (10).

[0233]

[Table 4]

Example 7 Using the image forming apparatus and toner (1) used in Example 1, the temperature is 20 ° C. and the humidity is 50%.
A4 CLC paper (Canon; 8;
An image having a total image density of 2% in which all solid images and character images were mixed was continuously printed on 15,000 sheets using 0 g / m ² ). 1st, 50th, 5000th, 1500
The following evaluation was performed using the 0th image.

Image Density Evaluation Regarding image density, Macbeth densitometer (manufactured by Macbeth Co.)
Was used as the total solid image density.

Evaluation of Image Fog Image fog was evaluated in the same manner as in Example 1 using the white solid portion of the image sample.

The evaluation results are shown in Table 5.

<Example 8> Image evaluation was carried out in the same manner as in Example 7 except that the toner (8) shown in Table 4 was used in place of the toner (1).

The evaluation results are shown in Table 5.

Example 9 Image evaluation was carried out in the same manner as in Example 7 except that the toner (9) shown in Table 4 was used instead of the toner (1).

The evaluation results are shown in Table 5.

<Comparative Example 4> Image evaluation was carried out in the same manner as in Example 7 except that the toner (10) shown in Table 4 was used in place of the toner (1).

The evaluation results are shown in Table 5.

[0244]

[Table 5]

[0245]

As described above, according to the present invention,
In electrostatic copiers, laser printers, etc., high-quality images can be obtained without causing image streaks or image fog even during long-term use under both high temperature and high humidity conditions and low temperature and low humidity conditions.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a toner regulating member of a developing device.

FIG. 2 is a schematic configuration diagram of an example of an apparatus for performing the image forming method of the present invention.

FIG. 3 is a schematic configuration diagram of an example of an image forming apparatus that collectively transfers multiple toner images onto a recording material by using an intermediate transfer body.

FIG. 4 is a schematic configuration diagram of an apparatus using an intermediate transfer belt.

FIG. 5 is a schematic configuration diagram of an apparatus in which toner images of respective colors are sequentially transferred and superposed on the same transfer material.

FIG. 6 is a schematic configuration diagram of another apparatus example for carrying out the image forming method of the present invention.

FIG. 7 is a schematic configuration diagram of another apparatus example for carrying out the image forming method of the present invention.

FIG. 8 is a schematic diagram of an image forming apparatus used in an example.

[Explanation of symbols]

1 photoconductor drum 2 Development roller (toner carrier) 3 Elasticity regulation blade 4 Non-magnetic toner

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Satoshi Handa             3-30-2 Shimomaruko, Ota-ku, Tokyo             Non non corporation (72) Inventor Yasuhiro Hashimoto             3-30-2 Shimomaruko, Ota-ku, Tokyo             Non non corporation (72) Inventor Koichiro Takashima             3-30-2 Shimomaruko, Ota-ku, Tokyo             Non non corporation F-term (reference) 2H005 AA01 AA21 CA08 DA10 EA03                       EA05 EA06 EA07 EA10 FA07                 2H077 AD06 DB14 EA14 GA13

Claims (12)

[Claims] 1. A toner for forming an image using a non-magnetic one-component developing method, which comprises at least a toner layer forming step in which a toner layer on a toner carrier is regulated by a toner regulating member. The regulation member has at least a resin layer having a resistance of 1.00 × 10 ⁴ Ω · cm or more, and the thickness of the resin layer is 5 μm.
m or more and less than 50 μm, the toner has at least a binder resin and a colorant, and contains a polyester compound in an amount of 50% by mass or more of the binder resin component, and gel permeation of a toluene-soluble component of the toner. Chromatography (GPC) measurement, 1.00 ×
The toner has a main peak between 10 ^{3 and} 3.00 × 10 ⁴ , and the toner insoluble component of the toner is 1% by mass or more and 70% by mass.
The toner has a water content of 100 ppm or more and less than 5000 ppm when left for 24 hours under low temperature and low humidity conditions, and has a particle size distribution in which the toner particles having a particle size of more than 16 μm are less than 5% by volume. Toner characterized by that. 2. The toner according to claim 1, which has a main peak between 3.00 × 10 ^{3 and} 1.00 × 10 ⁴ in GPC measurement of a toluene-soluble component. 3. A toluene insoluble component is 10% by mass or more and 60% or more.
The toner according to claim 1, wherein the toner is less than mass%. 4. A polyester compound is contained in an amount of 80% by mass or more of the binder resin component.
4. The toner according to any one of 3 to 3. 5. The toner according to claim 1, which has a water content of 300 ppm or more and less than 3000 ppm when left for 24 hours under low temperature and low humidity conditions. 6. The glass transition temperature (Tg) of the toner is 5
The toner according to any one of claims 1 to 5, which has a temperature of 0 ° C or higher and lower than 65 ° C. 7. An image forming method using a non-magnetic one-component developing method, the image forming method including at least a toner layer forming step in which a toner layer on a toner carrier is regulated by a toner regulating member. The regulation member has at least a resin layer having a resistance of 1.00 × 10 ⁴ Ω · cm or more, and the thickness of the resin layer is 5 μm.
m or more and less than 50 μm, the toner has at least a binder resin and a colorant, and contains a polyester compound in an amount of 50% by mass or more of the binder resin component, and gel permeation of a toluene-soluble component of the toner. Chromatography (GPC) measurement, 1.00 ×
The toner has a main peak between 10 ^{3 and} 3.00 × 10 ⁴ , and the toner insoluble component of the toner is 1% by mass or more and 70% by mass.
The toner has a water content of 100 ppm or more and less than 5000 ppm when left for 24 hours under low temperature and low humidity conditions, and has a particle size distribution in which the toner particles having a particle size of more than 16 μm are less than 5% by volume. An image forming method characterized by the above. 8. The image forming method according to claim 7, which has a main peak between 3.00 × 10 ^{3 and} 1.00 × 10 ⁴ in GPC measurement of a toluene-soluble component. 9. A toluene insoluble component is 10% by mass or more and 60
The image forming method according to claim 7, wherein the image forming amount is less than mass%. 10. The image forming method according to claim 7, wherein the polyester compound is contained in an amount of 80% by mass or more of the binder resin component. 11. The image forming method according to claim 7, which has a water content of 300 ppm or more and less than 3000 ppm when left for 24 hours under low temperature and low humidity conditions. 12. The glass transition temperature (Tg) of the toner is 50 ° C. or higher and lower than 65 ° C. 7.
12. The image forming method according to any one of 1 to 11.