JP2001125316A - Developer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a developer excellent in transparency and in the stability of the charged state and free form toner scattering. SOLUTION: The developer contains a colorant, a polyester resin having 90-120 deg.C softening point and a zirconium complex of a salicylic acid derivative and may further contain a natural wax having 65-90 deg.C melting point.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a developer for developing an electrostatic image in electrophotography, electrostatic recording, electrostatic printing and the like.

[0002]

2. Description of the Related Art In addition to black toner, cyan, yellow, and magenta toners are generally used for full-color copying machines and printers using an electrophotographic process. By fixing the color, a color development including a halftone is obtained.

In order to obtain a high color tone, each toner is required to have high transparency, and it is also necessary to obtain a uniform fixing surface with little roughness. Therefore, a low molecular weight polyester resin is generally used as a binder in a color toner. As a countermeasure against offset, a natural wax having a low melting point is used to maintain transparency.

[0004] Such a color toner has a low softening point,
Because there is a risk of sticking in the crusher during toner production,
By adding a lubricant such as metal soap, such inconvenience may be prevented. Further, in order to obtain a highly saturated color tone, the size of toner particles has been reduced.

[0005]

As described above, since a conventional full-color toner uses a soft resin as a binder resin, a so-called spent toner, which is a phenomenon in which the toner sticks to a carrier or a developing device according to life, is generated. Cheap. Therefore, it is difficult to maintain the chargeability over the life, and there is a problem that toner is easily scattered. The addition of wax also causes spent.

[0006] Further, metal soap compounded as an anti-filming agent for a photoreceptor has an action of adhering to a carrier or a charge controlling agent to reduce the ability to impart charge, so that the amount of charge decreases over its life and toner is scattered. Will cause. Further, when the size of the toner particles is reduced for the purpose of improving the image quality, the amount of fine powder toner increases, so that the spent toner is easily generated, and similarly, the problem of toner scattering occurs.

As described above, the full-color copying machine has a disadvantage that the life of the developer is short.

Accordingly, an object of the present invention is to provide a developer which is excellent in transparency and charge stability and does not cause toner scattering.

[0009]

In order to solve the above-mentioned problems, the present invention (claim 1) provides a coloring material and a softening point of 90 to 1
There is provided a developer comprising toner particles containing a polyester resin at 20 ° C. and a zirconium complex of a salicylic acid derivative.

[0010] The present invention (claim 2) provides toner particles containing a coloring material, a polyester resin having a softening point of 90 to 120 ° C, a zirconium complex of a salicylic acid derivative, and a natural wax having a melting point of 65 to 90 ° C. A developer is provided.

The developer of the present invention has a melting point of 100 to 140 ° C.
It is preferable to further contain a metal soap of

In the developer of the present invention, the ratio of toner particles having a particle size of 4 μm or less is 5 to 30% by number of the total number of toner particles, and the ratio of toner particles having a particle size of 12.7 μm or more is Is 5% by volume or less, and preferably has a particle size distribution with a volume average diameter of 6 to 10 μm.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.

The coloring material used in the present invention includes carbon black, organic or inorganic pigments and dyes, and the like. Although there is no particular restriction, examples of the carbon black include acetylene black, furnace black, thermal black, channel black, and Ketjen black. Examples of face dyes include, for example, Fast Yellow G, Benzimidazolone, Benzidine Yellow, Indofast Orange, Irgazine Red, Carmine FB, Permanent Bordeaux FRR, Pigment Orange R, Lysole Red 2G, Lake Red C, Rhodamine FB, Rhodamine B
Lake, phthalocyanine blue, pigment blue, brilliant green B, phthalocyanine green, and quinacridone. These coloring materials
They can be used alone or as a mixture.

The structure of the polyester resin used in the present invention is not particularly limited, and a commonly used thermoplastic polyester can be used. As used herein, the polyester resin refers to a resin having a main chain of a polymer obtained by ester condensation of a divalent acid and a dihydric alcohol, and a saturated or unsaturated monomer can be used. In the case of having an unsaturated double bond, it is possible to further copolymerize a vinyl monomer such as styrene, but it is not preferable if the crosslinking proceeds too much to become thermosetting.

As the monomer to be used, examples of the divalent acid include phthalic acid, terephthalic acid, fumaric acid, maleic acid, sebacic acid, succinic acid, and adipic acid. Examples of the dihydric alcohol include, for example, aliphatic glycols such as ethylene glycol, propylene glycol, butylene glycol, and butenediol, and more commonly, ethylene oxide adducts of aromatic bisphenol A, and propylene oxide. And adducts.

However, the polyester resin used in the present invention must have a softening point of 90 to 120 ° C. When a polyester resin having a softening point of less than 90 ° C. is used, offset occurs.
When a polyester resin having a softening point exceeding 20 ° C. is used, there is a disadvantage that the toner is not fixed.

In the present invention, the charge control agent (C
As the CA), a zirconium complex of a salicylic acid derivative is used. When a zirconium complex of a salicylic acid derivative is not blended, toner scattering occurs.

Examples of the zirconium complex of the salicylic acid derivative include those represented by the following general formula.

[0020]

Embedded image

In the above general formula (1), R ₁ and R ₂ are alkyl groups.

Examples of the natural wax that can be used in the present invention include rice wax, carnauba wax, candelilla wax, wood wax, beeswax, lanolin, montan wax and the like. Such wax is
Structurally, an ester of a higher fatty acid and a higher aliphatic alcohol is a main component, and unreacted higher fatty acids, higher alcohols, and other components are also included. By blending such a natural wax, transparency can be maintained, offset resistance can be improved, and less oil fixing can be achieved.

However, the natural wax used in the present invention must have a melting point of 65 to 90 ° C. When a wax having a melting point of less than 65 ° C. is used, the storage stability is reduced. On the other hand, when a wax having a melting point exceeding 90 ° C. is used, sufficient transparency cannot be obtained.

In the present invention, the formulation of the toner particles is not particularly limited. In general, toner particles are obtained by uniformly mixing and kneading a polyester resin, a colorant, and a charge control agent, and then pulverizing and classifying to a predetermined size.

As a mixing and dispersing method, a wet dispersing method using a high-speed dissolver, a roll mill, a ball mill, or the like;
A melt kneading method using a roll, a pressure kneader, an internal mixer, a screw-type extruder, or the like can be used. As a mixing means, a ball mill, a V-type mixer, a Folberg, a Henschel mixer, or the like can be used. it can.

As a means for coarsely pulverizing the mixture, for example, a hammer mill, a cutter mill, a jet mill, a roller mill, a ball mill and the like can be used. Further, as a means for finely pulverizing the coarsely pulverized product, a jet mill, a high-speed rotary pulverizer or the like can be used.

In the toner particles thus obtained, the ratio of toner particles having a particle size of 4 μm or less is 5 to 30% by number of the total number of toner particles, and the ratio of toner particles having a particle size of 12.7 μm or more is 5 vol. % Or less, and the volume average diameter is 6 to
It preferably has a particle size distribution of 10 μm.

If the volume average diameter is out of the above-mentioned range, there is a possibility that the obtained image quality is defective. Specifically, when the volume average diameter is less than 6 μm, fogging occurs. On the other hand, when the volume average diameter exceeds 10 μm, the resolution may be poor.

The developer of the present invention has a melting point of 100 to 140.
C. may be further added, and by blending the metal soap, photoreceptor filming can be favorably prevented. Examples of the metal soap that can be used include zinc stearate.

Further, the following external additives can be added. Specifically, as the external additive,
For example, silica fine particles, metal oxide fine particles, and a cleaning aid are used. As silica fine particles,
Examples include silicon dioxide, aluminum silicate, sodium silicate, zinc silicate, and magnesium silicate. Examples of the metal oxide fine particles include zinc oxide, titanium oxide, aluminum oxide, zirconium oxide, strontium titanate, and barium titanate. Examples of the cleaning aid include fine resin powders such as polymethyl methacrylate, polyvinylidene fluoride, and polytetrafluoroethylene, and may be used by adding 0.2 to 2 parts by weight as necessary. These external additives may have been subjected to a surface treatment such as hydrophobization with a silane coupling agent or the like.

These external additives can be added to the toner using a mixing device such as a Henschel mixer or a super mixer.

The developer of the present invention described above can be applied to, for example, an image forming apparatus as shown in FIG.

FIG. 1 is a schematic view showing an example of a full-color image forming apparatus to which the developer of the present invention can be applied.

In FIG. 1, a photosensitive drum 1a, which is an image carrier, is a cylindrical laminated organic photosensitive member having a diameter of 40 mm and a length of 266 mm, and is provided so as to be rotatable in the direction of the arrow shown in the figure.

The following are arranged around the photosensitive drum 1a along the rotation direction. That is, a charging roller 5a made of a conductive rubber roller for uniformly charging the photosensitive drum 1a is provided in contact with the surface of the photosensitive drum 1a, and the charged photosensitive drum 1a is provided downstream of the charging roller 5a. Is provided with an exposure section 7a for exposing the surface to form an electrostatic latent image. Further, a developing device 9a that accommodates a developer and develops the electrostatic latent image formed by the above-described exposure unit 7a with the developer is provided downstream of the exposure unit 7a. Downstream of the developing device 9a, a transport unit that transports the paper P as a transfer material to the photosensitive drum 1a is provided.

Further, the blade cleaning device 17 is located downstream of the contact position of the photosensitive drum 1a with the sheet P.
a and a static elimination lamp 19a. The blade cleaning device 17a removes the developer remaining on the photosensitive drum 1a after the transfer of the developer image described later to the blade 21.
To remove it. The charge removing lamp 19a is a tungsten lamp that removes light from the surface of the photosensitive drum 1a after transfer. This static elimination lamp 19
a. One cycle of image formation is completed by static elimination by a.
Next, when an image is formed, the uncharged photosensitive drum 1a is charged again by the charging roller 5a.

The conveying means 11 has a width substantially equal to the drum width of the photosensitive drum 1a. The transport means 11 is in the form of an annular belt, and a tension roller 13 and a drive roller 15 are provided on the upstream and downstream annular portions of the transport means 11, respectively. The transport means 11 is in contact with the tension roller 13 and the drive roller 15 along the outer circumference of the tension roller 13 and the drive roller 15 in this annular portion. In addition,
The distance from the tension roller 13 to the drive roller 15 is about 300 mm.

Tension roller 13 and drive roller 1
Numerals 5 are provided so as to be rotatable in the directions indicated by arrows i and j, respectively. With the rotation of the drive roller 15, the conveying means 11 is sent in a ring shape. The transport speed is controlled to be equal to the speed of the photoconductor.

In the vicinity of the conveying means 11, a paper feed cassette 25 for storing the paper P is provided. The paper feed cassette 25 is provided with a pickup roller 27 for picking up the sheets P one by one so as to be rotatable in a direction indicated by an arrow f. A registration roller pair 29 composed of an upper roller and a lower roller is rotatably provided in the transport direction of the sheet P taken out by the pickup roller 27 and in front of the transport unit 11. The registration roller pair 29 sends out the conveyed sheet P to the conveying unit 11 at a timing such that the leading end of the developer image formed on the photosensitive drum 1a comes to the leading end of the sheet P.

The fed sheet P is conveyed to a suction roller 24 installed in contact with the conveying means 11 at a position facing the tension roller 13 with the conveying means 11 interposed therebetween. The suction roller 24 is a SUS metal roller having a diameter of 6 mm. This may be a conductive rubber roller such as carbon-dispersed urethane rubber. Alternatively, a conductive brush or corona charger can be used.

The supply of the voltage to the suction roller 24 is performed by the power supply 4
1 is performed. The applied voltage here was -1.5 kV. The higher the applied voltage for the attraction, the more the amount of charge applied to the belt, the greater the amount of attraction, but there is a limit to the withstand voltage of the belt material (at most 3
kV).

The suction roller 24 rotates by following the annular belt. At the same time as the paper P is conveyed to the suction roller section, a suction bias is applied to the suction roller 24 from the power supply 41. Thus, the surface of the sheet P is negatively charged, and the opposite side of the belt (the tension roller 13 side) is positively charged. The sheet P can be attracted by the electrostatic force due to the charge.

The above-mentioned photosensitive drum 1a, charging roller 5
a, the exposure unit 7a, the developing unit 9a, the blade cleaning device 17a, and the charge removing lamp 19a constitute a process unit 100a.

The tension roller 1 is placed on the conveying means 11.
3 and the drive roller 15 along the transport direction, in addition to the process unit 100a, the process unit 100
b, process unit 100c, and process unit 100d (hereinafter, process unit 100a, process unit 100b, process unit 100c, and process unit 100d are collectively referred to as process unit 100). Process unit 10
0b, the process unit 100c, and the process unit 100d all have the same configuration as the process unit 100a.

That is, the photosensitive drum 1b, the photosensitive drum 1c, and the photosensitive drum 1d (hereinafter, the photosensitive drum 1a, the photosensitive drum 1b, the photosensitive drum 1c, and the photosensitive drum 1d are collectively referred to as the photosensitive drum 1d). 1) is provided substantially at the center of each process unit 100. Around the photosensitive drum 1, a charging roller 5 is provided.
b, charging roller 5c, and charging roller 5d (hereinafter, charging roller 5a, charging roller 5b, charging roller 5c, and charging roller 5d are collectively referred to as charging roller 5). On the downstream side of the charging roller 5, an exposure unit 7
b, exposure unit 7c and exposure unit 7d (hereinafter, exposure unit 7a,
The exposing unit 7b, the exposing unit 7c, and the exposing unit 7d are collectively referred to as an exposing unit 7); a developing unit 9b, a developing unit 9c, and a developing unit 9d (hereinafter, a developing unit 9a, a developing unit 9b, a developing unit 9c,
And the developing device 9d are collectively referred to as a developing device 9); a blade cleaning device 17b, a blade cleaning device 17c, and a blade cleaning device 17d (hereinafter, a blade cleaning device 17a, a blade cleaning device 17b, a blade cleaning device 17c,
And the blade cleaning device 17d are collectively referred to as a blade cleaning device 17);
b, the discharge lamp 19c, and the discharge lamp 19d (hereinafter, the discharge lamp 19a, the discharge lamp 19b, the discharge lamp 19c, and the discharge lamp 19d are collectively referred to as the discharge lamp 19).
Is the same as

The different configuration of each process unit is the developer housed in the developing unit.
a, yellow is stored in the process unit 100b, cyan is stored in the process unit 100c, and black is stored in the process unit 100d.

When a color image is output, the conveying means 1
1 are sequentially contacted with the respective photosensitive drums 1. At a contact position between the sheet P and each of the photosensitive drums 1, a power supply roller 23a, a power supply roller 23b, a power supply roller 23c, and a power supply roller 23d as transfer units are provided.
(Hereinafter, the power supply roller 23a, the power supply roller 23b, the power supply roller 23c, and the power supply roller 23d are collectively referred to as the power supply roller 23). Each of the photosensitive drums 1 is provided in one-to-one correspondence.

That is, the power supply roller 23 is positioned between the contact position between the corresponding photosensitive drum 1 and the conveying means 11 and the conveying means 1.
1 is provided in contact with the back surface of the photosensitive drum 1, and is opposed to the photosensitive drum 1 via the conveying means 11. The power supply roller 23a, the power supply roller 23b, the power supply roller 23c, and the power supply roller 23d are respectively connected to a bias power supply, which is a voltage application unit, although not shown in the figure. The power supply roller 23 is configured to rotate following the movement of the transport unit 11.

Here, the image forming process of the image forming apparatus thus configured will be described. The rotating photosensitive drum 1 of each of the above four process units is
First, it is uniformly charged to about -500 V by the contact charging roller 5 to which the AC superimposed DC bias is applied.

The photosensitive drum 1 uniformly charged by the charging roller 5 is irradiated with light from a solid-state scanning head (exposure unit 7) that performs exposure with a fluorescent material, and an electrostatic latent image is formed. The electrostatic latent image is developed by a developing unit 9 using a developer which is sufficiently charged in advance for each color.

On the other hand, the paper P is taken out of the paper feed cassette 25 by the pickup roller 27 and sent to the registration roller pair 29. The pair of registration rollers 29
After the timing of the rotation of the photosensitive drum 1 is set such that the leading end of the developer image comes to the leading end of the sheet P, the sheet P is sent out onto the conveying means 11.

When the sheet P is conveyed to the transfer position, a voltage of, for example, about 1400 V is applied as a bias voltage from the power supply rollers 23 to the conveying hand d11. By applying a bias voltage, a transfer electric field is formed between the photosensitive drum 1 and the transport unit 11. Therefore,
First, the developer image on the photoconductor drum 1a is transferred onto the paper P, and the paper P carrying the developer image is conveyed and reaches the photoconductor 1b. The developer image formed on the photoconductor drum 1b is transferred so as to be superimposed on the previously transferred developer image. The sheet P is further conveyed by the conveying means 11, and the developer images of the respective colors are similarly transferred on the photosensitive drums 1c and 1d.

As described above, the sheet P carrying the image formed by the multiple transfer is sent from the conveying means 11 to the fixing device 33. The fixing device 33 includes a heating roller 35 and a pressure roller 3.
The image P is fixed on the sheet P by passing the image between the heating roller and the pressure roller in a state where the image is in contact with the heating roller.

After the sheet P is separated from the transport means, the surface of the belt is cleaned by the blade cleaning 16.

[0055]

The present invention will be described in detail below with reference to examples and comparative examples.

In the present invention, in order to evaluate toner fixing, offset properties, images, life properties, and the like, a modified apparatus of the Toshiba Electronic Copier Premage 251 was used. FIG. 2 is a diagram showing a fixing device used for evaluating the toner characteristics of the present invention.

As shown, the apparatus comprises a heater 10
Heat roller 101 having a structure in which rubber is covered on a core metal containing 3 or a structure in which the surface is covered with a thin tube such as PFA or PTFE, a cleaning roller 104 provided on the heat roller 101, and a heat roller A pressure roller 102 is provided facing the heat roller 104 and is rotatable in synchronization with the heat roller 101. The cleaning roller 104 is for cleaning a small amount of toner stains, paper dust, and the like, and may be a roller impregnated with silicone oil.

In the offset confirmation experiment here,
No silicone oil was impregnated. The heat roller uses a PFA tube roller of φ40 for both upper and lower,
Roller hardness 70 °, nip width 6mm, load 55kgf,
The experiment was performed under the condition of a process speed of 127 mm / sec.

Example 1 91 parts by weight of a polyester resin having a softening point of 100 ° C., 3 parts by weight of an azo magenta pigment, 1 part by weight of a salicylic acid derivative zirconium complex (TN-105 manufactured by Hodogaya Chemical) as a charge control agent (CCA) And 5 parts by weight of rice wax having a melting point of 75 ° C. are uniformly mixed and kneaded with a pressure kneader, and then 2 m with a hammer mill.
Milled into m passes. Further, the powder was finely pulverized by a jet pulverizer, and the fine powder was cut by an airflow classifier to obtain magenta toner particles having a 50% volume particle size of 8.0 μm.

Further, 100 parts by weight of the toner particles described above,
Silica fine powder (Nippon Aerosil hydrophobic silica R97)
2) 1 part by weight, and 1 part by weight of zinc stearate,
The resulting mixture was mixed for 3 minutes with a Henschel mixer and sieved with a 200-mesh sieve to obtain the desired two-component negatively charged toner.

The toner was accommodated in a digital copying machine Premage 251 manufactured by Toshiba to form an image, and the image was evaluated. As a result, a clear magenta image could be obtained. The initial charge amount is 4.0 in Q / d (Fetom C / 10
μm Hosokawa Micron. Further, a good image was obtained even after a paper-passing test of 60,000 sheets, and toner scattering was good. The charge amount after 60,000 sheets was 3.8.

The same procedure as in Example 1 was repeated except that the softening point or CCA type of the binder resin blended in the sample of Example 1 was changed as shown in Table 1 below. The samples of Examples 1 to 8 were obtained. In Examples 2 to 3 and Comparative Examples 1 to 4, the softening point of the resin was changed, and in Comparative Examples 5 to 8, the CCA type was changed. These Examples 2-3 and Comparative Examples 1
Using the sample No. 8, an image was formed in the same manner as in Example 1, and the transparency, chargeability, and toner scattering were evaluated. The obtained results are summarized in Table 1 below.

[0063]

[Table 1]

As shown in Table 1, the present invention (Example 1)
In all of the samples of 3), good results were obtained with respect to transparency, charge amount, and toner scattering. On the other hand, in Comparative Example 1 in which a resin having a softening point of 121 ° C. was blended, fixing could not be performed, and in Comparative Example 3 in which a resin having a softening point of 89 ° C. was blended, offset occurred. Further, C
In all of the samples of Comparative Examples 5 to 8 which did not contain the salicylic acid derivative zirconium complex as CA, toner scattering occurred.

Next, Examples 4 to 6 and Examples 4 to 6 were prepared in the same manner as in Example 1 except that the melting point or the CCA type of the wax compounded in the sample of Example 1 was changed as shown in Table 2 below. Samples of Comparative Examples 9 to 16 were obtained. In Examples 4 to 6 and Comparative Examples 9 to 12, the melting point of the wax was changed, and in Comparative Examples 13 to 16, C was changed.
CA type was changed. Using the samples of Examples 4 to 6 and Comparative Examples 13 to 16, an image was formed in the same manner as in Example 1, and the transparency, chargeability, and toner scattering were evaluated and obtained. The results are summarized in Table 2 below.

[0066]

[Table 2]

As shown in Table 2, the present invention (Example 4)
In all of the samples 6) to 6), good results were obtained in transparency, charge amount, and toner scattering. On the other hand, in Comparative Example 9 in which a wax having a melting point of 91 ° C. was blended, the transparency was inferior, and in Comparative Example 11 in which a wax having a melting point of 64 ° C. was blended, storage stability was deteriorated. Further, in all of the samples of Comparative Examples 13 to 16 which did not contain the salicylic acid derivative zirconium complex as CCA, toner scattering occurred.

Next, the same procedure as in Example 1 was repeated except that the metal soap was removed from the sample of Example 1 or the CCA type was changed as shown in Table 3 below.
8 and Comparative Examples 17 to 20 were obtained. In Example 8, no metal soap was added, and Comparative Examples 17 to 2 were used.
At 0, the CCA species was changed. Examples 7 to
8 and Comparative Examples 17 to 20, images were formed in the same manner as in Example 1, and the filming of the photoreceptor, the chargeability, and the scattering of toner were evaluated. Summarize in 3.

[0069]

[Table 3]

As shown in Table 3, in the samples of the present invention (Examples 7 and 8), good results were obtained with respect to the charge amount and the toner scattering. In No. 7, the photoreceptor filming characteristics are also good. On the other hand, Comparative Examples 17 to 2 containing no zirconium complex of salicylic acid derivative as CCA
In each of the samples of 0, toner scattering occurred.

Further, Examples 9 to 13 and Comparative Examples 21 to 24 were carried out in the same manner as in Example 1 except that the 50% volume particle size or CCA type of the toner particles was changed as shown in Table 4 below. Sample was obtained. Example 10
In Examples 13 to 13, the 50% volume particle diameter of the toner particles was changed, and in Comparative Examples 21 to 24, the CCA type was changed.
Using the samples of Examples 9 to 13 and Comparative Examples 21 to 24, an image was formed in the same manner as in Example 1, and the image quality, chargeability, and toner scattering were evaluated. Are summarized in Table 4 below.

[0072]

[Table 4]

As shown in Table 4, in the sample of the present invention, good results were obtained with respect to image quality, charge amount, and toner scattering. In Examples 9 to 11, particularly excellent results were obtained. On the other hand, Comparative Example 2 containing no zirconium complex of a salicylic acid derivative as CCA
In the samples Nos. 1 to 24, not only toner scattering occurred but also the image quality was remarkably inferior.

[0074]

As described in detail above, according to the present invention,
A developer which is excellent in transparency and charge stability and free of toner scattering is provided. According to the present invention, even when a material in which toner scattering is inevitable is used in combination,
It is possible to improve the life of the developer by preventing toner scattering, and its industrial value is great.

[Brief description of the drawings]

FIG. 1 is a schematic diagram illustrating an example of a full-color image forming apparatus to which a developer of the present invention can be applied.

FIG. 2 is a schematic diagram illustrating a fixing device used for evaluating toner characteristics of the present invention.

[Explanation of symbols]

1a, 1b, 1c, 1d: Photoconductor drums 5a, 5b, 5c, 5d: Charging rollers 7a, 7b, 7c, 7d: Exposure units 9a, 9b, 9c, 9d: Developing device 11: Transport means 13: Tension roller 15 ... Driving rollers 17a, 17b, 17c, 17d ... Blade cleaning devices 19a, 19b, 19c, 19d ... Static elimination lamps 23a, 23b, 23c, 23d ... Power supply rollers 24 ... Adsorption rollers 25 ... Paper cassettes 27 ... Pickup rollers 29 ... Registration Roller pair 41 Power supply 100a, 100b, 100c, 100d Process unit 101 Fixing roller 102 Pressure roller 103 Heater 104 Cleaning roller

Claims (4)

[Claims] 1. A developer comprising toner particles containing a colorant, a polyester resin having a softening point of 90 to 120 ° C., and a zirconium complex of a salicylic acid derivative. 2. A developer comprising a toner particle containing a coloring material, a polyester resin having a softening point of 90 to 120 ° C., a zirconium complex of a salicylic acid derivative, and a natural wax having a melting point of 65 to 90 ° C. . 3. The developer according to claim 1, further comprising a metal soap having a melting point of 100 to 140 ° C. 4. The toner according to claim 1, wherein the proportion of toner particles having a particle diameter of 4 μm or less is 5 to 30% by number of the total number of toner particles, and the proportion of toner particles having a particle diameter of 12.7 μm or more is 5% by volume. 4. The developer according to claim 1, wherein the developer has a particle size distribution of 6 to 10 μm. 5.