JP3314290B2 - Non-magnetic one-component development method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-magnetic one-component developing method using a negative color toner.

[0002]

2. Description of the Related Art In recent years, as a method for developing an electrostatic latent image,
A method using a magnet roller having a sleeve provided with a magnetic field generating means inside and a magnetic one-component toner is popular, but the magnetic toner is not suitable for colorization because the magnetic substance mixed therein is black. Has disadvantages.

The developing operation in the method using a magnetic one-component toner is performed by rotating a sleeve, rotating an internal magnet, or rotating both of them. In order to prevent the magnetic pole pitch from appearing in the image, the rotation speed of the sleeve or the magnet is selected so that the moving speed of the magnetic toner is 2 to 4 times that of the latent image. Therefore, in order to ensure the uniformity of the image density, the number of rotations of the magnet becomes rapid and a powerful motor is required. Therefore, it naturally leads to an increase in the size of the device.

[0004] From such a background, a one-component developer having no magnetism is used as a color toner.
As disclosed in Japanese Patent Publication No. 75-75, a method of bringing a donor member having a thin layer of toner on the surface close to a latent image forming body and causing toner to fly only to the latent image in a non-contact state has been studied. Various proposals have also been made regarding retention of a thin toner layer.

For example, Japanese Patent Application Laid-Open No. 60-229065 discloses that a toner carrier is made endless so that it can be used repeatedly, and an elastic homogenizing member is brought into contact with a developer carrier roller to form a toner. Forming a thin layer,
It describes that development is performed by applying an AC and DC development bias. Further, Japanese Patent Application Laid-Open No. Sho 50-30537 discloses a method for increasing the image density by a pulse bias method. Further, Japanese Patent Application Laid-Open No.
No. 2635 and Japanese Patent Application Laid-Open No. Sho 50-10143 disclose the structure of a developing roller having a fine pattern of insulating and conductive properties on the surface. It forms valleys and attaches toner corresponding to the potential level of the latent image, aiming at multi-layering.

In any of the above methods, the amount of development on the photoreceptor changes depending on the state of the toner applied to the developing roller, so that the characteristics of the toner on the developing roller are important.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and is not only excellent in color reproducibility, but also has high image quality, and furthermore, the amount of applied toner and the amount of charge on a developing roller. Is stable even after long-term use, such as no toner contamination or fusing to the developing roller or developer coating blade even after long-term use. The purpose is to obtain a one-component developing method.

[0008]

According to the present invention, first, a toner supply member pressed against a developing roller and a developer application blade provided downstream of the toner supply member are used to form a negative color. A developing roller coated with a multi-layered toner and a latent image carrier composed of an organic photosensitive layer are brought into contact with each other in a developing section in contact or non-contact, and the latent image on the latent image carrier is reversely developed with color toner. In the non-magnetic one-component developing method, as the toner, a colorant,
A binder resin and a charge control agent, wherein the binder resin contains a polyol having the following components (a), (b), (c) and (d), and the charge control agent is a salicylic acid derivative metal salt. A non-magnetic one-component developing method characterized by using a certain one is proposed. (A) at least two or more bisphenol A epoxy resins having different number average molecular weights, (b) substituted or unsubstituted glycidyl ethers of alkylene oxide adducts of dihydric phenols, (c) bisphenols, (d) epoxy A compound having one active hydrogen in a molecule that reacts with a group.

Second, in the first method, (a)
A non-magnetic one-component developing method characterized by using a bisphenol A epoxy resin having the following constitutions (e) and (f). (E)
The number average molecular weight is 360 to 2000 (EEW 180 to 10
00) of 20 to 50% by weight, and (f) a number average molecular weight of 3000 to 10000 (EEW 1500 to 5
000) from 5 to 40% by weight.

Third, in the first method, as the color toner, silica fine particles having a volume average particle diameter of 4 to 10 μm and a hydrophobicity of 50% or more are present as external additives on the toner surface. And a non-magnetic one-component developing method characterized by using the following method.

Hereinafter, the present invention will be described in detail. First, the polyol as the binder resin in the present invention will be described. As described above, the polyol used in the present invention comprises the components (a) to (d). The component (a) is at least two or more bisphenol A epoxy resins having different number average molecular weights. One has a low molecular weight, and preferably has a number average molecular weight of 360 to 200.
0 (EEW 180 to 1000), the other having a high molecular weight, preferably having a number average molecular weight of 3000 to 1000
0 (EEW 1500 to 5000), and the component ratio is preferably 20 to 50% by weight for the former and 5 to 40% by weight for the latter.

The component (b) is a substituted or unsubstituted glycidyl ether of an alkylene oxide adduct of a dihydric phenol. Examples of the alkylene oxide adduct of a dihydric phenol which is reacted with a bisphenol used in the present invention include ethylene oxide, propylene oxide, butylene oxide and mixtures thereof.

The component (c) is, for example, bisphenols such as bisphenol A, AD and F.

The constituent component (d) is a compound having one active hydrogen in the molecule which reacts with the epoxy group.
As monohydric phenols, phenol, cresol,
Isopropylphenol, aluminum phenol, nonylphenol, dodecylphenol, xylenol, p-cumylphenol and the like.

These constituents are synthesized by the method shown in the synthesis examples described later to obtain the polyol according to the present invention.

Next, the charge control agent will be described. As the charge control agent used in the present invention, it is effective to add a colorless or white substance that does not impair the color tone of the color toner and stabilize the chargeability of the toner on the developing roller. Of these, addition of a metal salt of a salicylic acid derivative described below is particularly effective in stably imparting high toner chargeability.

Embedded image (In the formula, R ₃ , R ₄ and R ₅ are hydrogen, an alkyl group having 1 to 10 carbon atoms or an allyl group, particularly preferably hydrogen or an alkyl group having 1 to 6 carbon atoms. ₃ , R ₄ and R ₅ may be the same or different at the same time, and Me is zinc, nickel, cobalt,
Any metal selected from copper and chromium)

This compound is described in CLARK, J .; L. KA
O, H (1948) J. Amer. Chem. Soc.
70, 2151. For example, 2 mol of salicylic acid sodium salt (including the sodium salt of salicylic acid derivative) and 1 mol of zinc chloride are added to a solvent, mixed, heated and stirred to obtain a zinc salt. This metal salt is a white crystal and does not show coloring even when dispersed in a toner binder.
Metal salts other than zinc salts can also be produced according to the above method.

This compound has the effect of imparting non-charging properties to the toner and suppressing the change in the charging properties of the toner due to environmental changes. The amount is 0.1 to 10 parts by weight, preferably 1 to 7 parts by weight, based on 100 parts by weight of the binder resin.

The measurement of the charge amount of the toner on the developing roller is performed as follows.
Proceed as follows. The toner adhering to the developer carrier is sucked through a Faraday cage having a filter layer on the outlet side, and the weight and charge (Q / M) of the toner trapped in the Faraday cage are calculated.

The charge amount is preferably -5 to -30 .mu.C / g, more preferably -10 to -20 .mu.C / g, in consideration of sufficient developability and quality such as background fog. Further, the amount of toner adhered to the developing roller is calculated from the weight change per unit area by peeling off the toner layer with a tape (printable tape). The development amount of the toner on the latent image carrier is set in the same manner.

The volume average particle diameter of the toner is 4 to 10
More preferably, it is μm. As described above, by reducing the particle size, the resolution becomes better and the image quality can be improved. In particular, when used as a color toner, the difference in image quality such as color reproducibility due to the particle size is remarkable. The measurement of the volume average particle size is based on a coal tar multisizer.

The presence of fine silica particles having a hydrophobicity of 50% or more as an external additive on the toner surface improves the charge amount of the toner on the developer roller and the developability of the toner on the latent image bearing member. The change in the amount of charge of the toner on the developing roller due to the environmental conditions is reduced.

The degree of hydrophobicity of the external additive can be measured as follows. 50 ml of water is placed in a 20 ml beaker, and 0.2 g of an external additive is added. Then, with gentle stirring with a magnetic stirrer, add methanol from a burette whose tip was immersed in water at the time of dropping, and the external additive that had floated began to sink, and the number of ml of methanol dropped when it completely settled was read. Is calculated as the degree of hydrophobicity.

(Equation 1) (Where A is the number of ml of dropped methanol)

In this case, methanol has a surfactant, and the external additive floating with the dropwise addition of methanol is dispersed in water via methanol. The degree of hydrophobicity is high.

The degree of hydrophobicity of the external additive is controlled by subjecting the surface of the external additive to a surface treatment (hydrophobizing treatment) with a silane compound or the like. That is, the silane compound is reacted with the hydroxyl group bonded to the external additive to replace the hydroxyl group with a siloxyl group or the like, and the degree of hydrophobicity is lost by the above-mentioned reaction among the hydroxyl groups existing before the hydrophobicization. It is the ratio of hydroxyl groups.

The hydrophobic treatment is carried out by reacting an external additive with a dialkyldihalogenated silane, a trialkylhalogenated silane, a hexaalkyldisilane, an alkyltrihalogenated silane or the like at a high temperature.

In the binder resin of the present invention, the following resins can be mixed and used as needed. Styrene such as polystyrene, poly p-chlorostyrene, polyvinyltoluene and its substituted homopolymer; styrene-p-chlorostyrene copolymer, styrene-propylene copolymer, styrene-vinyltoluene copolymer, styrene-vinyl Naphthalene copolymer, styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer, styrene-
Octyl acrylate copolymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer, styrene-α-chloromethyl methacrylate copolymer, styrene-
Acrylonitrile copolymer, styrene-vinyl methyl ether copolymer, styrene-vinyl ethyl ether copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile- Indene copolymer,
Styrene-based copolymers such as styrene-maleic acid copolymer and styrene-maleic acid ester copolymer; polymethyl methacrylate, polybutyl methacrylate, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, polyester, polyurethane, polyamide, Epoxy resin, polyvinyl butyral, polyacrylic acid resin, rosin, modified rosin, terpene resin, phenol resin.

The coloring agents used in the present invention include carbon black, lamp black, ultramarine, aniline blue, phthalocyanine blue, phthalocyanine green,
Any conventionally known dyes and pigments such as Hansa Yellow G, Rhodamine 6G, Lake, Calco Oil Blue, Chrome Yellow, Quinacridone, Benzidine Yellow, Rose Bengal, triallylmethane dyes and the like may be used alone or in combination. sell. The amount of these colorants to be used is generally 1 to 30% by weight, preferably 3 to 20% by weight, based on the binder resin.

As the external additive, it is particularly preferable to use the silica having a hydrophobicity of 50% or more of the present invention.
If necessary, fatty acid metal salts (such as zinc stearate and aluminum stearate), metal oxides (such as titanium oxide, aluminum oxide, tin oxide and antimony oxide), and fluoropolymers may be used alone or in combination.

In the present invention, the linear velocity ratio between the developing roller on which the color toner is applied in multiple layers and the latent image carrier is 2: 1 to 1
Preferably, the ratio is 1: 1. That is, the ideal toner development amount on the latent image carrier is 0.8 to 2.0 m from the viewpoint of appropriate image density, background fog, and transfer rate to paper.
g / cm ² . In order to obtain such a high toner development amount by the non-magnetic one-component development method, it is necessary to apply a large amount of toner on the developing roller and to increase the rotation linear speed of the developing roller compared to the latent image carrier. is there. However, when the linear velocity of the developing roller is extremely increased, the deviation of the toner toward the rear end of the image and the scattering of the toner from the developing roller are likely to occur. Therefore, the linear velocity ratio between the developing roller and the latent image carrier is determined by the present inventors,
It has been found that a ratio of 2: 1 to 1: 1, preferably 1.5: 1 to 1: 1 is preferred.

Hereinafter, a synthesis example of the binder resin of the present invention and a comparative synthesis example are shown. (Synthesis Example 1) 378.7 g of low-molecular bis-A-type diglycidyl ether (EEW: 180) and high-molecular bis-A in a separable flask equipped with a stirrer, thermometer, N ₂ inlet, and condenser.
Condensed diglycidyl ether (EEW: 1500) 9
4.65 g, diglycidylated product of bisphenol A-type propylene oxide adduct (EEW: 320)
4 g, 264.4 g of bisphenol F, 72.25 g of p-cumylphenol, and 200 g of xylene were added. N ₂
The temperature was raised to 70 to 100 ° C. under an atmosphere, 0.183 g of lithium chloride was added, the temperature was further raised to 160 ° C., xylene was distilled off under reduced pressure, and polymerization was carried out at a reaction temperature of 180 ° C. for 6 to 9 hours. Thus, 1000 g of a modified epoxy polyol resin having a softening point of 111 ° C. and a Tg of 59 ° C. was obtained (hereinafter, this resin is referred to as resin 1).

(Synthesis Example 2) Using the apparatus of Synthesis Example 1, low-molecular bis-A-type diglycidyl ether (EEW: 180)
216.05 g, 54.0 g of a polymer bis-A condensed diglycidyl ether (EEW: 1500), 432.1 g of a diglycidylated product of a bisphenol A-type propylene oxide adduct (EEW: 320), bisphenol F2
66.65 g, p-cumylphenol 28.9 g, and xylene 200 g were charged into a separable flask. The temperature was raised to 70 to 100 ° C. in an N ₂ atmosphere, 0.183 g of lithium chloride was added, the temperature was further raised to 160 ° C., xylene was distilled off under reduced pressure, and the polymerization was carried out at a reaction temperature of 180 ° C. for 6 to 9 hours. Thus, 1000 g of a modified epoxy polyol resin having a softening point of 111 ° C. and a Tg of 59 ° C. was obtained (hereinafter, this resin is referred to as resin 2).

(Synthesis Example 3) Using the apparatus of Synthesis Example 1, low-molecular bis-A-type diglycidyl ether (EEW: 180)
447.8 g, 335.85 g of a polymer bis-A condensed diglycidyl ether (EEW: 5000), 111.95 g of a diglycidylated product of a bisphenol A-type ethylene oxide adduct (EEW: 960), bisphenol A
D28.75 g, p-cumylphenol 75.65 g,
200 g of xylene was charged into a separable flask. N
₂ Raise the temperature to 70 ° C in an atmosphere and add lithium chloride
83 g was added, and the temperature was further raised to 160 ° C., xylene was distilled off under reduced pressure, and polymerized at a reaction temperature of 180 ° C. for 6 to 9 hours to obtain 1000 g of a modified epoxy polyol resin having a softening point of 111 ° C. and a Tg of 59 ° C. (Hereinafter, this resin is referred to as resin 3).

(Synthesis Example 4) Using the apparatus of Synthesis Example 1, a low-molecular bis-A-type diglycidyl ether (EEW: 100)
0) 329.3 g, polymer bis-A condensed diglycidyl ether (EEW: 5000) 247.0 g, bisphenol A-type ethylene oxide adduct diglycidylated product (EEW: 960) 329.3 g, bisphenol AD
55.1 g, p-cumylphenol 39.3 g, and xylene 200 g were charged into a separable flask. The temperature was raised to 70 to 100 ° C. in an N ₂ atmosphere, and lithium chloride was added to 0.1 mL.
183 g was further added, and the temperature was raised to 160 ° C., xylene was distilled off under reduced pressure, and polymerized at a reaction temperature of 180 ° C. for 6 to 9 hours to obtain 1000 g of a modified epoxy polyol resin having a softening point of 111 ° C. and a Tg of 59 ° C. (Hereinafter, this resin is referred to as resin 4
).

(Synthesis Example 5) Using the apparatus of Synthesis Example 1, low-molecular bis-A-type diglycidyl ether (EEW: 340)
427.65 g, 106.9 g of a polymer bis-A condensed diglycidyl ether (EEW: 3250), 213.8 g of a diglycidylated product of a bisphenol A-type ethylene oxide adduct (EEW: 320), bisphenol F1
75.35 g, 76.3 g of p-cumylphenol, and 200 g of xylene were charged into a separable flask. The temperature was raised to 70 to 100 ° C. in an N ₂ atmosphere, 0.183 g of lithium chloride was added, the temperature was further raised to 160 ° C., xylene was distilled off under reduced pressure, and the polymerization was carried out at a reaction temperature of 180 ° C. for 6 to 9 hours. Thus, 1000 g of a modified epoxy polyol resin having a softening point of 111 ° C. and a Tg of 59 ° C. was obtained (hereinafter, this resin is referred to as resin 5).

(Synthesis Example 6) Using the apparatus of Synthesis Example 1, low-molecular bis-A-type diglycidyl ether (EEW: 340)
230.8 g, polymer bis-A condensed diglycidyl ether (EEW: 3250) 57.7 g, bisphenol A
Diglycidylation of ethylene oxide adduct (EE
W: 320) 461.55 g, bisphenol F21
6.8 g, p-cumylphenol 33.15 g, and xylene 200 g were charged into a separable flask. The temperature was raised to 70 to 100 ° C. in an N ₂ atmosphere, and lithium chloride was added to 0.1 mL.
183 g was further added, and the temperature was raised to 160 ° C., xylene was distilled off under reduced pressure, and polymerized at a reaction temperature of 180 ° C. for 6 to 9 hours to obtain 1000 g of a modified epoxy polyol resin having a softening point of 111 ° C. and a Tg of 59 ° C. (Hereinafter referred to as resin 6
).

(Comparative Synthesis Example 1) Using the apparatus of Synthesis Example 1, a low-molecular bis-A-type diglycidyl ether (EEW: 3) was used.
40) 420.75 g, diglycidylated product of bisphenol A type ethylene oxide adduct (EEW: 640)
350.65 g, Bisphenol A 183.35 g, p
-45.25 g of cumylphenol and 200 g of xylene were charged into a separable flask. N ₂ 70~ in an atmosphere
The temperature was raised to 100 ° C., 0.183 g of lithium chloride was added, the temperature was further raised to 160 ° C., xylene was distilled off under reduced pressure, and polymerized at a reaction temperature of 180 ° C. for 6 to 9 hours.
1000 g of a modified epoxy polyol resin having a softening point of 111 ° C. and a Tg of 59 ° C. was obtained (hereinafter, this resin is referred to as comparative resin 1).

(Comparative Synthesis Example 2) Using the apparatus of Synthesis Example 1, low-molecular bis-A-type diglycidyl ether (EEW: 3)
40) 477.5 g, 286.5 g of a polymer bis-A condensed diglycidyl ether (EEW: 3250), 101.15 g of bisphenol A, p-cumylphenol 13
4.85 g and 200 g of xylene were charged into a separable flask. The temperature was raised to 70 to 100 ° C. in an N ₂ atmosphere,
0.183 g of lithium chloride was added, the temperature was further raised to 160 ° C., xylene was distilled off under reduced pressure, and the mixture was polymerized at a reaction temperature of 180 ° C. for 6 to 9 hours to obtain a softening point of 111 ° C. and a Tg of 59.
Thus, 1000 g of a modified epoxy polyol resin at a temperature of .degree.

(Synthesis Example 7) Using the apparatus of Synthesis Example 1, low-molecular bis-A-type diglycidyl ether (EEW: 340)
550.0 g, high-molecular bis-A condensed diglycidyl ether (EEW: 3250) 40.0 g, bisphenol A
Diglycidylation of ethylene oxide adduct (EE
W: 320) 120.0 g, bisphenol F200.
0 g, p-cumylphenol 90.0 g, xylene 20
0 g was charged into a separable flask. The temperature was raised to 70 ° C. in an N ₂ atmosphere, and 0.183 g of lithium chloride was added.
Further, the temperature was raised to 160 ° C., xylene was distilled off under reduced pressure, and polymerization was carried out at a reaction temperature of 180 ° C. for 6 to 9 hours to obtain 1000 g of a modified epoxy polyol resin having a softening point of 111 ° C. and a Tg of 59 ° C. The resin is referred to as resin 7).

(Synthesis Example 8) Using the apparatus of Synthesis Example 1, low-molecular bis-A-type diglycidyl ether (EEW: 100)
0) 180.0 g, 450.0 g of a polymer bis-A condensed diglycidyl ether (EEW: 5000), 120.0 g of a diglycidylated product of a bisphenol A-type ethylene oxide adduct (EEW: 960), bisphenol F2
00.0 g, p-cumylphenol 50.0 g, and xylene 200 g were charged into a separable flask. The temperature was raised to 70 ° C. in an N ₂ atmosphere, and 0.183 g of lithium chloride was added.
In addition, the temperature was further raised to 160 ° C., xylene was distilled off under reduced pressure, and polymerized at a reaction temperature of 180 ° C. for 6 to 9 hours to obtain a modified epoxy polyol resin having a softening point of 111 ° C. and a Tg of 59 ° C. This resin is referred to as resin 8).

By using the binder resin shown in the above synthesis example, the amount of toner applied and the amount of charge on the developing roller are less changed even after long-term use, and toner contamination and fusing to the developing roller and the developer application blade are prevented. There is no occurrence.
Further, the color toner is excellent in necessary color reproducibility, stable gloss, transparency, and environmental stability.

Among these binder resins, in particular, at least two or more bisphenol A type epoxy resins having different number average molecular weights have a number average molecular weight of 3 or more.
20 to 50% of low molecular weight components having a molecular weight of 60 to 2000 (EEW 180 to 1000) and a number average molecular weight of 3000 to 100
00 (EEW 1500-5000) with a polymer component of 5
It was clarified that the amount of toner applied on the developing roller and the amount of charge were stable even after long-term use by setting the amount to 40% by weight.

According to the toner using the binder resin according to the present invention, the amount of toner applied and the amount of charge on the developing roller are stable even after long-term use, and toner contamination and fusing on the developing roller and the developer applying blade. Adhesion and the like are less likely to occur because the toner is less likely to be deformed even when the developing unit is agitated, and the external additives that adhere to the toner surface for the purpose of improving fluidity are less buried in the toner surface. It is presumed that the toner is hardly pulverized.

The salicylic acid derivative metal salt as a charge control agent has a very good dispersibility in the binder resin, and is considered to have an effect of stabilizing the chargeability of the toner.

Further, by using a small particle size toner having a volume average particle size in the range of 4 to 10 μm, the charge amount and the application amount of the toner on the developing roller become stable even after long-term use.

[0046]

Embodiments will be described below with reference to embodiments.

Example 1 Toners of respective colors were prepared according to the compositions shown in Table 1 below.

[0048]

[Table 1]

After being sufficiently mixed by a blender according to the above composition, the mixture was melt-kneaded by two rolls heated to 100 to 110 ° C. After the kneaded product was allowed to cool naturally, it was coarsely pulverized by a cutter mill, pulverized by a fine pulverizer using a jet mill airflow, and then subjected to a volume classifier of 11.1 μm using an air classifier.
m of each color particle were obtained.

Further, a surface treatment was performed with a titanium-based coupling agent. Titanium oxide fine particles having a hydrophobicity of 45%
5 parts by weight was mixed with 100 parts by weight of each color particle by a mixer.

Next, the toner was loaded into the developing device shown in FIG. The developing roller of this developing device has a silicone resin as a main component as a surface layer, and a blade that comes into contact with the developing roller is formed of a urethane material. The evaluation was performed by using a laser printer manufactured by Ricoh equipped with a belt-shaped organic photoreceptor as the latent image carrier, and setting the linear velocity ratio between the developing roller and the latent image carrier to be 1.2. Was.
In the first embodiment, the evaluation was performed by bringing the latent image carrier into contact with the developing roller. However, in other embodiments, the evaluation was performed without contact (gap: 150 μm). Some linear velocity ratios were also changed (see Table 2-1 (summary)). Further, only the example of the cyan toner is described in the second embodiment and thereafter.

The evaluation results of Example 1 are summarized as follows. After transferring the images of the respective toners to copy paper and fixing them with a heat roller, clear images of the respective colors were obtained. Similarly, red, blue,
A clear image was obtained also in the green fixed image and the fixed image obtained by the three-color superposition development, and no abnormalities such as uneven gloss, curl, and background fog were observed.

Further, when the full-color image was fixed on a transparent sheet for an overhead projector (OHP) and projected by the OHP, a clear full-color image without turbidity was projected.

Further, a storage experiment was conducted in which the full-color image was brought into close contact with a vinyl chloride sheet and allowed to stand at room temperature for 180 hours. No transfer to this sheet was observed, and the full-color image was favorably maintained.

Also, 10 g of each color toner is weighed,
After placing in a 0 cc glass container and leaving it in a thermostat set at 50 ° C. for 24 hours, the penetration was measured by a penetration meter, and the penetration of all the toners was 5 or more.

Table 2-2 shows the results of evaluation on toner developability, such as the amount of toner adhered to the developing roller, performed on the cyan toner, along with other examples and comparative examples.
Published in

Example 2 Binder resin (resin 8 obtained in Synthesis Example 8) 100 parts by weight Charge control agent (salicylic acid derivative Zn salt) 4 parts by weight Colorant (copper phthalocyanine blue pigment) 2 parts by weight Same as Example 1 To a volume average particle size of 11.5 μm
Was obtained. Further, 0.5 parts by weight of silica fine particles having a hydrophobicity of 45%, which had been surface-treated with a silane coupling agent, were mixed with 100 parts by weight of the cyan particles by a mixer to obtain a toner. This toner was evaluated for developability in the same manner as in Example 1. Table 2-
It is shown in FIG.

Example 3 Binder resin (resin 3 obtained in Synthesis Example 3) 100 parts by weight Charge control agent (salicylic acid derivative Zn salt) 4 parts by weight Colorant (copper phthalocyanine blue pigment) 2 parts by weight Same as in Example 1 To a volume average particle size of 10.9 μm
Was obtained. Further, 0.6 parts by weight of silica fine particles having a hydrophobicity of 45%, which had been surface-treated with a silane coupling agent, were mixed with 100 parts by weight of the cyan particles with a mixer to obtain a toner. This toner was evaluated for developability in the same manner as in Example 1. Table 2-
It is shown in FIG.

Example 4 Binder resin (resin 4 obtained in Synthesis Example 4) 100 parts by weight Charge control agent (salicylic acid derivative Zn salt) 4 parts by weight Colorant (copper phthalocyanine blue pigment) 2 parts by weight Same as in Example 1 To a volume average particle size of 10.4 μm
Was obtained. Further, 0.7 parts by weight of silica fine particles having a hydrophobicity of 45%, which had been surface-treated with a silane coupling agent, were mixed with 100 parts by weight of the cyan particles with a mixer to obtain a toner. This toner was evaluated for developability in the same manner as in Example 1. Table 2-
It is shown in FIG.

Example 5 Binder resin (resin 5 obtained in Synthesis Example 5) 100 parts by weight Charge control agent (salicylic acid derivative Zn salt) 4 parts by weight Colorant (copper phthalocyanine blue pigment) 2 parts by weight Same as Example 1 To obtain cyan particles having a volume average particle size of 7.8 μm. Further, 0.75 parts by weight of silica fine particles having a degree of hydrophobicity of 70% subjected to a surface treatment with a silane coupling agent were mixed with 100 parts by weight of the cyan color particles by a mixer to obtain a toner. This toner was evaluated for developability in the same manner as in Example 1. Table 2 shows the evaluation results.
-2.

Example 6 Binder resin (resin 6 obtained in Synthesis Example 6) 100 parts by weight Charge control agent (salicylic acid derivative Zn salt) 4 parts by weight Colorant (copper phthalocyanine blue pigment) 2 parts by weight Same as Example 1 To obtain cyan particles having a volume average particle size of 6.6 μm. Further, 0.8 parts by weight of silica fine particles having a hydrophobicity of 80%, which had been surface-treated with a silane coupling agent, were mixed with 100 parts by weight of the cyan particles with a mixer to obtain a toner. This toner was evaluated for developability in the same manner as in Example 1. Table 2-
It is shown in FIG.

Comparative Example 1 Binder resin (resin obtained in Comparative Synthesis Example 1) 100 parts by weight Charge control agent (salicylic acid derivative Zn salt) 4 parts by weight Colorant (copper phthalocyanine blue pigment) 2 parts by weight Same as in Example 1 To a volume average particle size of 11.5 μm
Was obtained. Further, 0.5 parts by weight of silica fine particles having a hydrophobicity of 45%, which had been surface-treated with a titanium-based coupling agent, were mixed with 100 parts by weight of the cyan particles by a mixer to obtain a toner. This toner was evaluated for developability in the same manner as in Example 1. Table 2-
It is shown in FIG.

Comparative Example 2 Binder resin (resin obtained in Comparative Synthetic Example 2) 100 parts by weight Charge control agent (salicylic acid derivative Zn salt) 4 parts by weight Colorant (copper phthalocyanine blue pigment) 2 parts by weight Same as in Example 1 To a volume average particle size of 11.5 μm
Was obtained. Further, 0.5 parts by weight of silica fine particles having a hydrophobicity of 45%, which had been surface-treated with a silane coupling agent, were mixed with 100 parts by weight of the cyan particles by a mixer to obtain a toner. This toner was evaluated for developability in the same manner as in Example 1. Table 2-
It is shown in FIG.

Comparative Example 3 100 parts by weight of a binder resin (resin 1 obtained in Synthesis Example 1) 4 parts by weight of a charge controlling agent (fluorinated quaternary ammonium salt) 2 parts by weight of a coloring agent (copper phthalocyanine blue pigment) Treated in the same manner as described above to obtain a volume average particle size of 11.4 μm.
Was obtained. Further, 0.6 parts by weight of silica fine particles having a hydrophobicity of 45%, which had been surface-treated with a silane coupling agent, were mixed with 100 parts by weight of the cyan particles with a mixer to obtain a toner. This toner was evaluated for developability in the same manner as in Example 1. Table 2-
It is shown in FIG.

Comparative Example 4 Binder resin (polyester resin synthesized from bisphenol A type alcohol and terephthalic acid: softening point 110 ° C.) 100 parts by weight Charge control agent (salicylic acid derivative Zn salt) 4 parts by weight Colorant (copper phthalocyanine blue pigment) 2 parts by weight were treated in the same manner as in Example 1 to obtain cyan particles having a volume average particle size of 6.8 μm. Further, 0.5 parts by weight of silica fine particles having a degree of hydrophobicity of 70% subjected to a surface treatment with a silane coupling agent were mixed with 100 parts by weight of the cyan particles with a mixer to obtain a toner. This toner was evaluated in the same manner as in Example 1. Table 2 shows the evaluation results.
-2.

Comparative Example 5 Binder resin (styrene-n-butyl methacrylate copolymer: softening point 112 ° C.) 100 parts by weight Charge control agent (salicylic acid derivative Zn salt) 4 parts by weight Colorant (copper phthalocyanine blue pigment) 2 parts by weight Was treated in the same manner as in Example 1 to obtain a volume average particle size of 11.3 μm.
Was obtained. Further, 0.6 parts by weight of silica fine particles having a degree of hydrophobicity of 70%, which had been surface-treated with a silane coupling agent, were mixed with 100 parts by weight of the cyan particles with a mixer to obtain a toner. This toner was evaluated in the same manner as in Example 1. Table 2 shows the evaluation results.
-2.

[0067]

[Table 2- (1)]

[0068]

[Table 2- (2)]

(Note) In Table 2-2, "30,000 sheets" means after printing 30,000 sheets, and "styrene-acryl" means a styrene-n-butyl-methacrylate copolymer.

Table 2-2 shows that the toner of Example has a slightly lower "toner charge amount on developing roller" after printing 30,000 sheets than the initial value. Amount of adhesion and amount of toner development on latent image carrier
Is almost the same as the initial value after 30,000 prints,
Further, it can be seen that good results are also obtained for "fusion to the developing roller and the developer coating blade" and "fogging on the background of the image".

On the other hand, in Comparative Example 1 synthesized using only a low-molecular-weight epoxy resin without using a high-molecular-weight bisphenol A-type epoxy resin as a polyol component, the "toner on developing roller" after printing 30,000 sheets The amount of charge is significantly reduced.

In Comparative Example 2 in which the glycidylated product of the alkylene oxide adduct of dihydric phenol was not used as the polyol component, the “toner adhesion amount on the developing roller” and the “toner development amount on the latent image carrier” were determined. The drop is large.

On the other hand, in the case of Comparative Example 3 using a fluorine-containing quaternary ammonium salt instead of the salicylic acid derivative Zn salt as the charge controlling agent, the “toner adhering amount on the developing roller” and the “toner electrifying amount on the developing roller” were low. In both cases, the initial values are low and the decrease after printing 30,000 sheets is remarkable. In addition, the "toner development amount on the latent image carrier" after printing 30,000 sheets is greatly reduced.

[0074]

As described above, the developing roller coated with the multi-layered negative color toner and the latent image carrier composed of the organic photosensitive layer are formed in the developing section by the toner supply member on the developing roller and the developer coating blade. According to the non-magnetic one-component developing method of contacting or non-contacting the latent image on the latent image carrier and reversal developing the latent image on the latent image carrier with the color toner, the toner using the binder resin according to the present invention has a long term. The amount of toner applied and the amount of charge on the developing roller are stabilized by the use of the toner, and toner contamination, fusion and the like on the developing roller and the developer applying blade hardly occur.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing an example of a developing device used in a non-magnetic one-component developing method according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Latent image carrier 2 Developing roller 2-1 Core metal 2-2 Resin coat layer 3 Toner supply member 4 Developer coating blade 5 Agitator

────────────────────────────────────────────────── ─── Continued on the front page (51) Int.Cl. ⁷ Identification code FI G03G 15/08 507 G03G 9/08 361 15/09 101 15/08 507L (72) Inventor Minoru Masuda Minoru Nakamagome 1, Ota-ku, Tokyo JP-A-5-142859 (JP, A) JP-A-61-285461 (JP, A) JP-A-5-224492 (JP, A) JP-A-61-77057 (JP, A) JP-A-58-203456 (JP, A) JP-A-3-94269 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G03G 9 / 08

Claims (3)

(57) [Claims] An image forming apparatus comprising: a developing roller coated with a multi-layered negative color toner and an organic photosensitive layer by a toner supply member pressed against the development roller and a developer application blade provided downstream of the toner supply member. A non-magnetic one-component developing method comprising: contacting the latent image carrier with the latent image carrier in a developing unit in a contact or non-contact manner; and performing reversal development of the latent image on the latent image carrier with a color toner. , A binder resin and a charge control agent, wherein the binder resin contains a polyol having the following components (a), (b), (c) and (d) as components, and
A non-magnetic one-component developing method, wherein the charge control agent is a salicylic acid derivative metal salt. (A) at least two or more bisphenol A epoxy resins having different number average molecular weights; (b) substituted or unsubstituted glycidyl ethers of alkylene oxide adducts of dihydric phenols; (c) bisphenols; (d) epoxy A compound having one active hydrogen in a molecule that reacts with a group. 2. The non-magnetic one-component developing apparatus according to claim 1, wherein the bisphenol A type epoxy resin represented by the above (a) has the following constitutions (e) and (f). Method. (E) The number average molecular weight is 360 to 2000 (EEW180
(F) a number average molecular weight of 3000 to 10000 (EEW1);
5 to 40% by weight of a polymer component (500 to 5000). 3. The color toner according to claim 1, wherein silica fine particles having a volume average particle diameter of 4 to 10 μm and a hydrophobicity of 50% or more are present on the toner surface as an external additive. Item 1. The non-magnetic one-component developing method according to Item 1.