JPH0396964A - Image forming method - Google Patents

Abstract

PURPOSE:To suppress moisture adsorptivity by using a metallic ion crosslinked nonlinear polyester which is a resin contg. trivalent and higher valency monomers and in which an ion crosslinking bond is generated by the coordination of polyvalent metallic ions in the hydrophilic functional group as the resin to be incorporated into a toner and enclosing the hydrophilic functional group with metallic ions. CONSTITUTION:The photosensitive layer 4 consisting of a carrier generating layer 2 and a carrier transfer layer 3 is formed on a conductive supporting body 1. The electrostatic latent image formed on the photosensitive layer 4 is then developed by using the toner and after this image is transferred onto a recording material, the toner remaining on the photosensitive layer 4 is removed by a cleaning blade. For example, 443g polyoxypropylene (2, 2)-2, 2-bis(4- hydroxyphenyl)propane, 176g polyoxyethylene (2)-2, 2-bis(4- hydroxyphenyl)propane, 120g terephthalic acid, and 0.8g diisopropyl orthotitanate are used as the resin to be incorporated into the toner.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an image forming method using a toner containing a specific non-linear polyester. The electrostatic latent image is developed with a toner containing a specific non-linear polyester, and after this toner image is transferred to a recording material, the toner remaining on the organic photoconductive photoreceptor is removed with a cleaning blade. Concerning an image form precept method including processes.

[Conventional technology]

Image forming methods using toner generally include a charging step in which the surface of a photoconductor is charged with a uniform potential, an exposure step in which the charged surface of the photoconductor is imagewise exposed to form an electrostatic latent image, a development step of developing the electrostatic latent image with toner; a transfer step of transferring the toner image obtained by development onto a recording material;
The process consists of a fixing process for fixing the transferred I/toner, and a cleaning process for removing toner remaining on the surface of the photoreceptor after the transfer.

In recent years, organic photoconductive photoconductors having a photosensitive layer made of various organic photoconductive substances have attracted attention as photoconductors. Organic photoconductive photoreceptors are superior to inorganic photoconductive photoreceptors made of selenium, cadmium sulfide, or the like in terms of film resistance, light weight, and productivity.

On the other hand, non-cotton-like polyester is known as a resin for toner. This non-linear polyester plays a major role in improving the offset resistance of the toner.

[Problems to be Solved by the Invention] However, since the surface of the organic photoconductive photoreceptor has a small Binkers hardness of about 10 to 30, when cleaning with a cleaning blade, the surface of the organic photoconductive photoreceptor is Since it is difficult to increase the pressure contact force of the cleaning blade, there is a problem in that cleaning defects are likely to occur when toner containing non-linear polyester is used.

In other words, in the production of non-linear polyester, a large amount of unreacted hydrophilic functional groups such as carpoxyl groups and hydroxyl groups tend to remain, and images cannot be produced in a high-temperature, high-humidity environment with a non-linear polyester of 80%. It becomes even more noticeable when it forms.

SUMMARY OF THE INVENTION An object of the present invention is to provide an image forming method that can effectively clean toner with a cleaning blade even in a high temperature and high humidity environment, and can also form an image without image fading. .

[Means to solve the problem]

In order to achieve the above object, in the present invention, an electrostatic latent image formed on an organic photoconductive photoreceptor is developed with a toner, and after this toner image is transferred to a recording material, an organic photoconductive photoreceptor is developed. In an image forming method including a step of removing toner remaining on the body with a cleaning blade, the toner is a non-linear polyester obtained from a monomer containing a trivalent or higher polyvalent monomer, and a hydrophilic polyester. The method uses a toner containing a metal ion crosslinked nonlinear polyester in which polyvalent metal ions are coordinated to the sexual functional groups to form ionic crosslinks.

Furthermore, even when unstellated toner with a maximum adsorbed moisture content of 0.4% by weight is melt-kneaded with other toner materials, the hydrophilic functional groups of non-cotton polyester tend to increase due to oxidation. The functional groups increase the moisture adsorption of the toner, which increases the physical adhesion between the toner and the organic photoconductive photoreceptor, making it extremely difficult to clean the toner with a cleaning blade.

In addition, since the toner has a high water adsorption property, the toner filmed on the surface of the organic photoconductive photoreceptor adsorbs water, greatly reducing the surface resistance of that area, and as a result, the electrostatic potential at that area. There is a problem in that the image is distorted and "image blur" is likely to occur.

Furthermore, in the image formation process, the hydrophilic functional groups of non-linear polyester tend to increase due to oxidation caused by ozone generated from chargers and transfer devices, so forming images multiple times may result in poor cleaning and image blurring. occurs significantly.

The above problems are particularly serious, for example, at temperatures of 33°C and relative temperatures of ~4°C.
Preferably, it is one man.

That is, the present invention does not use a nonlinear polyester containing a large amount of hydrophilic functional groups such as carboxyl groups and hydroxyl groups as it is, but uses metal ion crosslinking in which the hydrophilic functional groups are sealed with polyvalent metal ions. By using non-linear polyester in the mold, the moisture adsorption of the toner is suppressed to a low level, and as a result, the physical adhesion to the organic photoconductive photoreceptor is weakened, making cleaning with a cleaning blade easier. This method effectively prevents the occurrence of image deletion by reducing the amount of water adsorbed on the 1-toner filmed on the surface of the photoconductive photoreceptor, thereby suppressing the decrease in surface resistance caused by the water.

The toner used in the present invention is a non-linear polyester obtained from a monomer containing a polyvalent monomer of trivalent or higher valence, and a polyvalent metal ion is coordinated to a hydrophilic functional group to form an ionic crosslinking bond. This is a metal ion crosslinked nonlinear polyester formed.

Among polyvalent monomers having a valence of 3 or more, polyol monomers include sorbitol, 1.2.3.6-hexanetetrol, 14-sorbitan, pentaerythritol, dipentaerythritol, tripentaerythritol, sucrose. , 1,2,4-butanetriol, I. ．． 2.5-pentanetriol, glycerol, 2-methylpropanetriol, 2-methyl-1 2 4-butanetriol, trimethylolethane, trimethylolpropane, 1
3 5-trihydroxymethylhensen and the like can be used.

Examples of polycarboxylic acid monomers among trivalent or higher polyvalent monomers include 1.2.4-Hensentricarboxylic acid, 1,2.
5-benzenetricarboxylic acid, 12,4-cyclohexanetricarboxylic acid, 2,57-naphthalenetricarboxylic acid, 1,2.4-naphthalenetricarboxylic acid, 1,2.
4-butanetricarboxylic acid, I,2,5-hequinanetricarboxylic acid, 1,3-dicarboxyl-2-methyl-2
Methylene carboxylic propane, tetra(methylene carboxylic) methane, biromerisotonic acid, 1.7 nil) propane, polyoxyethylene (2.0) 2 2
-bis(4-hydroxyphenyl)propane, borioxypropylene (2,0)-bolyoxyethylene (2.0
)-2,2-bis(4-hydroxyphenyl)propane, borioxypropylene(6,0)-2,2-bis(4
-hydroxyphenyl)propane and other etherified bisphenols. In particular, etherified bisphenols greatly contribute to improving triboelectric charging properties.

Along with trivalent or higher polyvalent monomers, divalent polycarboxylic acid monomers that can be used in the production of nonlinear polyester include maleic acid, fumaric acid, succinic acid, adipic acid, sebacic acid, and malonic acid. Examples include itaconic acid, citraconic acid, mesaconic acid, glutaconic acid, cyclohexanedicarboxylic acid, phthalic acid, isophthalic acid, terephthalic acid, anhydrides or lower alkyl esters of these acids.

The blending ratio of trivalent or higher polyvalent monomers is 2.7.
8-octante I lacarboxylic acid, cyclohexanetetracarboxylic acid, 1.2.5.6-hexanetetracarboxylic acid, embol trimer acid, anhydrides or lower alkyl esters of these acids, and the like can be used. especially,
Benzenetricarboxylic acids are effective in forming ionic crosslinks with polyvalent metal ions.

Examples of divalent polyol monomers that can be used in the production of nonlinear polyesters together with trivalent or higher polyvalent monomers include ethylene glycol, diethylene glycol, triethylene glycol, l2-propylene glycol,
Diols such as 3-propylene glycol, 1,4-butanediol, neopentyl glycol, 1,4-butenediol, bisphenols such as 1,4-bis(hydroxymethyl)cyclohexane, bisphenol A, hydrogenated bisphenol A, Borioxypropylene (2
．． 2)-2.2-(4-hydroxydiphenyl)propane, polyoxypropylene (3.3)-2.2-bis(4-hydroxyphenyl) 0.1 to 80 mol%, preferably 5 to 50% Within this range, the offset resistance can be satisfied and the remaining hydrophilic functional groups can be sufficiently sealed with polyvalent metal ions.

As the polyvalent metal element that becomes the polyvalent metal ion for obtaining the metal ion crosslinked nonlinear polyester, Mg. Ca
, Ba, Zn, AI, Ti, Sn, etc. In particular, alkaline earth metals (Mg, CaBa) and zinc group elements (Zn) are preferred, and Mg and Z
n is preferred.

These polyvalent metal elements are subjected to the reaction in the form of a compound. Such polyvalent metal compounds include, for example, fluorides, chlorides, chlorates, bromides, iodides, oxides, hydroxides, sulfides, sulfites, sulfates of the above metal elements,
selenide, telluride, nitride, nitrate, phosphide,
Examples include phosphinates, phosphates, carbonates, or-1-silicates, acetates, oxalates, and lower alkyl metal compounds such as methyl compounds or ethyl compounds. Particularly preferred are acetates or oxides of the above metal elements.

The blending ratio of the polyvalent metal compound is 1 part polyvalent monomer with 3 or more valences
The amount is about 0.1 to 1 mole.

As a method for forming an ionic crosslinking bond by coordinating a polyvalent metal ion to a hydrophilic functional group, the following method h can be mentioned.

(1) A polyvalent metal compound or a dispersion solution of the polyvalent metal compound is added to a solution containing a nonlinear polyester obtained by an esterification reaction of a monomer compound containing a polyvalent monomer of trivalent or higher valence. Mix, raise the temperature, and perform solvent removal treatment for about 1 to 3 hours until the temperature of the reaction system is 150 to 180'C.
A method in which the reaction is completed by maintaining the temperature at this temperature for more than one hour.

(2) Before starting the esterification reaction to obtain a nonlinear polyester, a polyvalent metal compound is present in the reaction system,
How to perform a reaction.

(3) A method in which the reaction is completed by melt-kneading the product obtained by performing the solvent removal treatment in the above (1) using a roll, kneader, extruder, etc.

Although it contains the metal ion crosslinked non-11 obtained as described above, it may also contain other ingredients such as a coloring agent, a fixability improving agent, etc., as necessary.

Examples of the coloring agent include carbon black, other dyes, and pigments.

Examples of the fixability improver include polyolefin wax made of polypropylene and the like.

Further, inorganic fine particles surface-treated with a nitrogen-containing T substance may be further added and mixed to the toner obtained as described above to form a toner. According to such toner,
It exhibits suitable positive chargeability and can be preferably applied to negatively chargeable organic photoconductive photoreceptors.

Silica, alumina, titanium oxide, etc. can be used as the inorganic fine particles before surface treatment.

As the nitrogen-containing substance for surface treating these inorganic fine particles, amino-modified silicone is preferable. Specifically, the softening point of the chin-modified silane cutpurin linear polyester is preferably about 100 to 150°C from the viewpoint of improving offset resistance and fixing properties.

Here, the softening point is measured using a flow tester rCFT500 (manufactured by Shimadzu Corporation) under a load of 20k+!
/cm2, nozzle diameter 1mm, nozzle length 1mm,
Plunger drop of the flow tester obtained when preheating at 40°C for 10 minutes at a heating rate of 6°C/min and measuring and recording the sample ilcm3 (weight expressed as intrinsic specific gravity Xlcm3) vs. temperature peak curve (Softening flow curve) When the height of the S-shaped curve is h, it refers to the temperature when h/2.

The acid value of the metal ion crosslinked nonlinear polyester used in the present invention is preferably 2 to 50, particularly preferably IO to 30. When the acid value is within this range, moisture adsorption can be sufficiently suppressed, cleaning performance can be further improved, and image deletion can be more effectively prevented.

In the toner used in the present invention, the metal ion crosslinked nonlinear polyester as described above is an essential ingredient, and a glue agent, amino-modified silicone oil, etc. can be used.

Examples of methods for surface treating inorganic fine particles with amino-modified silicone include the following methods.

(1) A method in which inorganic fine particles are dispersed in a solution of amino-modified silicone dissolved in a solvent, and then the solvent is removed by filtration or spray drying, followed by drying and curing by heating.

(2) A method of spraying a solution of amino-modified silicone dissolved in a solvent to coat inorganic fine particles using a fluidized bed apparatus, and then removing the solvent by heating and drying to form a film.

In the i-free fine particles surface-treated with a nitrogen-containing substance, the average particle size of the primary particles is preferably 3 to 2000 mμ, particularly 5 to 500 mμ, and the specific surface area according to the BET method is 20 to 500 m / g. It is preferable that there be. Within this range, the toner cleaning performance of the cleaning blade is further improved.

The addition and mixing ratio of the inorganic fine particles whose surface has been treated with a nitrogen-containing substance is 0.1 to 5% by weight of the toner, particularly 0.1 to 5% by weight of the toner.
1 to 2% by weight is preferred.

In addition, when obtaining a magnetic toner, fine particles of a magnetic material such as magnetite or ferrite are contained in the toner particles.

The maximum adsorbed moisture content of the toner is preferably less than 0.4% by weight.

Here, the maximum amount of moisture adsorbed by a toner is a value obtained by placing 1 g of toner in an environment of a temperature of 33° C. and a relative humidity of 80%, sufficiently humidifying the toner, and then measuring the toner using the Karl Fischer method. Note that "toner" is a concept that includes external additives such as inorganic fine particles.

Since the maximum adsorbed moisture content of the toner is less than 0.4% by weight, the cleaning performance is further improved in a high temperature and high temperature environment of 33°C and relative humidity of 80%, and the occurrence of image deletion is prevented. This can be prevented even more effectively.

When a two-part developer is used, the carrier used with the toner is preferably magnetic particles.

As the carrier generating substance, a polycyclic quinone compound or the like can be used.

As the carrier transport substance, hydrazone compounds, styryl compounds, etc. can be used.

Organic photoconductive photoreceptors include a photosensitive layer and a conductive support.
It is structured in n layers.

As such a conductive support, a material obtained by vapor-depositing a metal such as aluminum on a plastic film such as polyethylene terephthalate 1 can be used.

Specific examples of the structure of the organic photoconductive photoreceptor are shown in FIGS. 1 to 4.

FIG. 1 shows a photosensitive layer consisting of a laminate of a conductive support layer 1, a carrier generation layer 2 mainly containing a carrier generation substance, and a carrier transport layer 3 mainly containing a carrier transport substance. This is a precept that has 4 points.

FIG. 2 shows a structure in which an intermediate layer 5 is provided on a conductive support 1, and a photosensitive layer 4 of the structure shown in FIG. 1 is provided on this intermediate layer 5.

Preferably, a coated carrier is formed by forming a coating layer of a resin such as a fluororesin on the surface.

In the present invention, using a toner containing the above specific metal ion crosslinked nonlinear polyester,
After the electrostatic latent image formed on the organic photoconductive photoconductor is developed with toner and the toner image is transferred to a recording material, the toner remaining on the organic photoconductive photoconductor is removed by a cleaning blade. The toner image transferred to the recording material is fixed by a heat roller fixing device or the like to form a fixed image.

The organic photoconductive photoreceptor used in the present invention is provided with a photosensitive layer containing an organic photoconductive substance.

The photosensitive layer is preferably composed of a binder resin containing an organic photoconductive substance dispersed therein.

Polycarbonate or the like can be used as such binder resin.

The photosensitive layer preferably has a laminated structure consisting of at least a carrier generation layer and a carrier transport layer.

Further, if necessary, an intermediate layer and an adhesive layer may be provided (16).
Photosensitive layer 4 formed by separating fine particulate carrier-generating substance 7
are provided on a conductive support 1.

FIG. 4 shows a structure in which an intermediate layer 5 is provided on a conductive support 1, and a photosensitive layer 4 having the structure shown in FIG. 3 is provided on this intermediate layer 5.

Next, an image forming apparatus that can be used to implement the image forming method of the present invention will be described.

FIG. 5 shows an outline of the image forming apparatus, in which 10 is an organic photoconductive photoreceptor, 21 is a charger, 22 is an exposure optical system, 23 is a developing device, 24 is a transfer device, 25 is a cleaning device, and 25A is a A cleaning blade, 26 a fixing device, and 30 a recording material.

The surface of the organic photoconductive photoreceptor 10 is first charged to a uniform potential by the charger 21 .

The uniformly charged surface of the organic photoconductive photoreceptor 10 is imagewise exposed by the exposure optical system 22 to form an electrostatic latent image on the surface.

This electrostatic latent image is developed by a developing device 23 to form a toner image corresponding to the electrostatic latent image.

The toner image obtained by the development is transferred onto the recording material 30 by the transfer device 24.

The toner image transferred onto the recording material 30 is fixed by a heat roller by the fixing device 26 to form a fixed image.

On the other hand, toner remaining on the organic photoconductive photoreceptor 10 without being transferred is scraped off and removed by a cleaning blade 25A in the cleaning device 25.

The surface of the cleaned organic photoconductive photoreceptor 10 is
It is uniformly charged again by the charger 21 and used for forming the next image.

〔Example〕

Examples of the present invention will be specifically described below along with comparative examples. Note that the embodiments of the present invention are not limited to the following examples. Furthermore, in the following description, "parts" represent "parts by weight" unless otherwise specified.

<Production of Photoconductor> 19 An organic photoconductive photoconductor was produced. This is called “Photoconductor A
”.

Structural formula (a) Photoreceptor B In the production of photoreceptor 8 above, the hydrazone compound represented by structure 2 (a) was changed to 11.25 g of a styryl compound represented by the following structural formula (b), and picryl A carrier generation layer with a thickness of about 0.5μ was prepared in the same manner except that the chloride was changed to 0.11 g of tetrabromoacetic anhydride.
A carrier transport layer having a thickness of about 12 μm was formed to produce an organic photoconductive photoreceptor having a functionally separated photosensitive layer. This will be referred to as "photoreceptor B."

Photoreceptor A A vinyl chloride-vinyl acetate-maleic anhydride copolymer "S-LEC M
F-1o" (manufactured by Sekisui Chemical Co., Ltd.) with a thickness of approximately 0. ]
Provide an intermediate layer of μ, 2X10-' to 3X10-'
Under a vacuum atmosphere of Torr, 4.10-dibromanthanthrone, a polycyclic quinone compound, was extracted with Monolite Red 2 YJ (C.I. No. 59300, LC.
1. A carrier-generating layer having a thickness of approximately 0.5 μm was formed by heating and evaporating a carrier-generating layer (manufactured by Nippon Steel & Co., Ltd.) at a temperature of 350° C. for 3 minutes, and depositing it on the intermediate layer.

On the other hand, 11.25 g of a hydrazone compound represented by the following structural formula (al), 0.028 g of picryl chloride,
Polycarbonate “Banlight L-1250J (
(manufactured by Teijin Kakaisha) was dissolved in 100 g of 1,2-dichloroethane, and the resulting solution was applied onto the carrier generation layer using a doctor blade and dried at a temperature of 80°C for 1 hour. A carrier transport layer with a thickness of about 12μ is formed, and a functionally separated photosensitive layer is provided.20 Structural formula (b) <Production of resin for toner> Resin A (for the present invention) Polyoxypropylene (2.2) -2 ．． 2-
443 g of bis(4-hydroxyphenyl)propane,
176g of polyoxyethylene(2)-2,2-bis(4-hydroxyphenyl)propane and 12g of terephthalic acid.
0 g and 0.8 g of diisoprobyl orthotitanate (esterification catalyst) in a container equipped with a thermometer, a stainless steel stirrer, a glass nitrogen gas inlet tube, and a down-flow condenser. ．． Place the flask in a round-bottomed flask, set the flask on a mantle heater, introduce nitrogen gas from the nitrogen gas inlet tube to maintain an inert atmosphere inside the flask, raise the temperature to 230°C, and stir. The reaction was carried out below. The acid value was measured to be 1.5 at the time when no viable water flowed out due to the reaction.

Furthermore, 139 g of 124-benzenetricarboxylic acid anhydride and 9 g of zinc oxide were added and reacted for about 8 hours. The reaction was terminated when the acid value reached 17, and the softening point was 132°. A metal ion crosslinked nonlinear polyester of C was produced. This will be referred to as "Resin A".

Resin B (for the present invention) Polyoxypropylene (2.2)-2. 482 g of 2-bis(4-hydroxyphenyl)broban, 126 g of polyoxyethylene(2)-2.2-bis(4-hydroxydiphenyl)propane, 1. 24 g of quinanediol to 6, 1174 g of fumar, and 0.8 g of diisoprobyl orthodicunate (esterification catalyst) were reacted in the same manner as in the production of resin 8 above, and then 1, 2.
77 g of 4-Hensentricarboxylic acid anhydride and 6 g of magnesium oxide were added and reacted for about 8 hours until the acid number reached 22. The mixture was stirred at 23 °C for 15 hours, and then the mixture was further heated to room temperature at atmospheric pressure. The mixture was stirred for 3 hours to produce inorganic fine particles A whose surface had been treated with a nitrogen-containing substance. The inorganic fine particles A had an average primary particle diameter of 12 mμ and a specific surface area of 130 m''/g by the BET method.

Inorganic fine particles B 00 parts of silica fine powder "Aerosil 200J (manufactured by Nippon Aerosil Co., Ltd.) were placed in a high-speed rotating mixer, and then amino-modified silicone oil r S F8417J with an ano equivalent of 3500 and a viscosity at 25°C of 1200 cps
A treatment solution prepared by dissolving 10 parts of hexamethyldisilazane r S Z6079J (manufactured by Toray Silicone Co., Ltd.) and 8 parts of Hexamethyldisilazane r S Z6079J (manufactured by Toray Silicone Co., Ltd.) in 100 parts of hexane was added dropwise to the high-speed rotating mixer. After surface treatment, the contents of the mixer were transferred to a flask and heated under an inert gas atmosphere at a temperature of 100 to 150°C for 5 hours with stirring to remove hexane, the solvent, and to initiate the reaction. By proceeding, inorganic fine particles B treated with a nitrogen-containing substance were manufactured. The reaction of the inorganic fine particles B was terminated when the average size of primary particles was reached, and a metal ion crosslinked nonlinear polyester having a softening point of 130°C was produced. This will be referred to as "Resin B".

Resin C (for comparison) A non-linear polyester not crosslinked with metal ions having a softening point of 125°C was produced in the same manner as in the production of Resin 8 except that zinc oxide was not used. This will be referred to as "resin C."

<Manufacture of inorganic fine particles> Inorganic fine particles A Silica fine powder "Aerosil 200J (manufactured by Nippon Aerosil Co., Ltd.) was placed in a mixer, and the silica fine powder was
γ-Aminopropyl I.Rie 1 diluted with alcohol so that the amino-modified silane coupling agent was 5% by weight.
- Added xysilane and stirred at high speed. After drying the obtained fine powder at 120°C, it was put into the mixer again, and while stirring, dimethyl silicone oil having a viscosity of 100 cps at 25°C was added to the silica fine powder at a concentration of 2%. Sprayed. Stir at high speed for 2 hours at room temperature,
In addition, 16024 has a diameter of 13 mμ and a specific surface area of 180 m27 by BET method.
It was g.

<Manufacture of toner> Toner 1 (for the present invention) Resin A ----- 111------
---------- 100 parts polypropylene wax
--------- 38 "Viscoll 660P
J (manufactured by Sanyo Kakai Industries) Carbon black
-----------1---- Part 10 "Mogul LJ
(manufactured by Cabot Corporation) The above materials were mixed, melted and kneaded using heating rolls, cooled, and then coarsely ground.Furthermore, they were pulverized using an ultrasonic jet mill, and classified using an air classifier to obtain an average particle size of 11. A powder of 0μ was obtained.

For 100 parts of this powder, 0.8 of the inorganic fine particles 8
A toner was prepared by mixing the two parts using a Henschel mixer. This is referred to as "toner 1".

The maximum adsorbed water content of this Toner 1 was 0.33% by weight.

Toner 2 (for the present invention) A toner was produced in the same manner as in the production of Toner 1 except that resin A was changed to resin B.

This will be referred to as "toner 2". The maximum adsorbed water content of this toner 2 was 0.35%.

Toner 3 (for the present invention) A toner was produced in the same manner as in Toner 1, except that inorganic fine particles A were replaced with inorganic fine particles B.

This will be referred to as "toner 2". The maximum adsorbed moisture content of this Toner 2 was 0.38%.

Toner 4 (for comparison) A toner was produced in the same manner as in the production of Toner 1 except that resin A was changed to resin C.

This will be referred to as "toner 3." The maximum adsorbed moisture content of this toner 3 was 0.55% by weight.

Preparation of developer> Each of the above toners 1 to 4 was mixed with a coating carrier consisting of spherical ferrite particles rF-150J (manufactured by Nippon Tetsuko Kogyo Co., Ltd.) with a coating layer made of a fluororesin on the surface. Developers 1 to 4 having a toner concentration of 4% by weight were prepared.

Example 1 Using a modified electrophotographic copying machine rtJ-Bix 1550J (manufactured by Konica ■) equipped with photoreceptor A and a cleaning blade, and developer 1, the temperature was 33°C and the relative humidity was 80%. In a high temperature and high humidity environment, the electrostatic latent image formed on the photoreceptor A is developed with toner L, and this toner image is transferred to a recording material made of plain paper.
We conducted a continuous live-photography test 30,000 times in which the toner remaining on the photoreceptor A was removed using a cleaning blade, while the toner transferred to the recording material was fixed using a heat roller fixing device to form a fixed image. The quality of cleaning performance and the occurrence of image deletion were evaluated.

Examples 2 to 5 and Comparative Example 1 A photographic test was conducted and evaluated in the same manner as in Example 1, except that the photoreceptor and developer were changed as shown in Table 1 below.

The above results are shown in Table 1 below.

As can be understood from the results in Table 1, Examples 1 to 5 of the present invention have good cleaning properties and do not cause image deletion.

On the other hand, according to Comparative Example 1, since the toner resin was non-linear polyester that was not crosslinked with metal ions, the cleaning performance was poor and image deletion was likely to occur.

〔Effect of the invention〕

As explained in detail above, according to the invention of claim 1,
The resin contained in the toner is a non-linear polyester obtained from a monomer containing a trivalent or higher polyvalent monomer, and a polyvalent metal ion is coordinated to a hydrophilic functional group to form an ionic crosslinking bond. It is a metal ion cross-linked non-linear polyester in which a polyester is formed, and the hydrophilic functional groups are sealed with polyvalent metal ions, so that the water adsorption of the toner is suppressed to a low level. As a result, even in high-temperature, high-humidity environments, less water is adsorbed to the i-ner, and the physical adhesion force caused by this water to the organic photoconductive photoreceptor is reduced. ... Charger 22 ... Exposure optical system 2
3...Developer 24...Transfer device 25...
-Cleaning device 25A...Cleaning blade 26...Fixing device 30...Recording material cleaning becomes easy, and moreover, less moisture is absorbed by the toner filmed on the surface of the organic photoconductive photoreceptor. Since the decrease in surface resistance due to moisture is suppressed,
Images can be formed without image deletion.

According to the invention of claim 2, the maximum adsorbed moisture amount of the toner is 0.
．． Since the amount is less than 4% by weight, the moisture adsorption of the toner is sufficiently small, and it is possible to stably reshape images without causing cleaning defects and without image fading over a large number of times.

[Brief explanation of drawings]

1 to 4 are schematic cross-sectional views showing specific examples of the structure of an organic photoconductive photoreceptor, and FIG. 5 is a schematic view of an image forming apparatus that can be used to implement the present invention. 1... Conductive support 2... Carrier generation layer 3
...Carrier transport N 4...Photosensitive layer 5...Intermediate layer 6...Layer 7 whose main component is a carrier transport substance...Carrier generation? ! l quality 10...organic photoconductive photoreceptor 3
1 One Cow Figure 3 Figure 12 Figure

Claims (2)

[Claims] (1) After developing the electrostatic latent image formed on the organic photoconductive photoreceptor with toner and transferring this toner image to a recording material,
In an image forming method including a step of removing toner remaining on an organic photoconductive photoreceptor with a cleaning blade, the toner is a non-linear polyester obtained from a monomer containing a polyvalent monomer of trivalent or higher valence. An image forming method comprising using a toner containing a metal ion crosslinked nonlinear polyester in which a polyvalent metal ion is coordinated to a hydrophilic functional group to form an ionic crosslinking bond. (2) The image forming method according to claim 1, wherein the maximum adsorbed moisture content of the toner is less than 0.4% by weight.