JP3284802B2 - Electrostatic toner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrostatic charge developing toner used in electrophotography, electrostatic printing and electrostatic recording. More specifically, the present invention relates to an electrostatic charge developing toner having excellent low-temperature fixability.

[0002]

2. Description of the Related Art In recent years, excellent low-temperature fixing characteristics have been demanded for toners from the viewpoint of miniaturization and energy saving of image forming apparatuses. If low-temperature fixing is realized, not only energy saving of the image forming apparatus can be achieved, but also warm-up time can be shortened, and more comfortable operability can be obtained. As the size of the image forming apparatus is reduced, the size of the fixing roller also needs to be reduced. Accordingly, it is necessary to use a fixing roller having a small diameter. When the diameter of the fixing roller is reduced, the nip width of the pair of fixing rollers is reduced, so that more excellent fixing characteristics for the toner are required. This requirement is particularly important for low-temperature fixing.

On the other hand, when the size of the fixing roller is reduced, when the roller heater is turned on, the roller is temporarily heated to a high temperature of 200 ° C. or higher. Therefore, a high-temperature offset characteristic is also required in the initial stage of the operation until the roller temperature reaches a low-temperature steady state. For a toner that can be fixed in a wide temperature range from a low temperature region to a high temperature region, both an anti-offset agent for securing a non-offset region in a low temperature region and an anti-offset agent for securing a non-offset region in a high temperature region are required.

However, the anti-offset agent often causes filming on the photoreceptor and the developing sleeve and also causes toner fog. This problem is particularly remarkable in the non-magnetic one-component developing system. In the non-magnetic one-component developing method, a charged toner thin layer is formed on the developing sleeve by the toner regulating member, but the offset applied to the developing sleeve due to the stress applied to the toner during toner regulation is prevented. Filming of the agent occurs.
Further, since the non-magnetic one-component toner is developed in contact with the photoconductor, the free offset preventing agent is more likely to adhere to the photoconductor than in the two-component development system. Therefore, it is difficult to solve this problem simply by using two kinds of offset preventing agents as described above.

Various proposals have been made for low-temperature fixing toners. For example, JP-A-60-25236
No. 6 discloses that the composition contains a binder resin and two kinds of release agents, and in the example, a combination of a wax having an acid group and a non-polar wax is described. . In the present invention, the non-offset property with respect to the low-temperature fixing property is good, but there is a problem in the dispersibility of the non-polar wax with the binder resin. Filming of the wax released to the toner carrier causes image noise such as a decrease in image density. JP-A-03-57
No. 64 discloses the use of a low melting point carnauba wax having an acid group as a release agent,
Since only carnauba wax is used, the non-offset property in a low temperature region is good, but there is a problem in the offset property in a high temperature region.

[0006]

SUMMARY OF THE INVENTION It is an object of the present invention to provide an electrostatic charge developing toner which has a wide non-offset area and does not cause filming on a photoreceptor or the like and can be fixed from a low temperature to a high temperature area. It is.

[0007]

According to the present invention, there is provided a polyester resin containing at least a binder resin, two kinds of offset inhibitors and a colorant, wherein the binder resin contains at least etherified diphenol and dicarboxylic acid as main components. It is a resin having an acid value of 15 to 50, and the softening point of the anti-offset agent 1 is 6
0 to 108 ° C., an acid value of 3 to 45, the softening point of the offset preventing agent 2 115 to 150 DEG ° C., an acid value of 1 to 30, an offset inhibitor 1
Carnauba wax, sasol wax, rice wack
, Candelilla wax, jojoba oil wax, beeswax
Selected from wax and oxidized polyethylene wax
The anti-offset agent 2 is an oxidized polyethylene wax
And an oxidized polypropylene wax .

In the present invention, two kinds of anti-offset agents having softening points in a low-temperature region and a high-temperature region are used as an anti-offset agent in order to prevent an offset in a fixing operation over a wide temperature range from a low temperature to a high temperature. At the same time, a polar anti-offset agent is used instead of the conventional non-polar one, and the polar anti-offset agent is added to the polar polyester resin by nature. Thus, the added anti-offset agent can be fused to the photoreceptor, the effect of preventing filming by the polyester resin can be satisfactorily exerted, and the occurrence of the offset phenomenon can be satisfactorily prevented.

The polyester resin used in the present invention is synthesized from a polyol component and a dicarboxylic acid. The polyol component contains at least an etherified diphenol, and the etherified diphenol is bisphenol A or di- (4-hydroxyphenyl). Methane diphenyls, ethylene oxide, propylene oxide, diethylene glycol, triethylene glycol, polyethylene glycol, dipropylene glycol, polypropylene glycol, polytetramethylene ether glycol, glycerol, trimethylolpropane, pentaerythritol, dipentaerythritol And an adduct with a compound selected from the group consisting of tripentaerythritol and maleic acid, fumaric acid, Konin acid, citraconic acid, itaconic acid, glutaconic acid, phthalic acid, isophthalic acid, terephthalic acid, succinic acid, adipic acid, sebacic acid, malonic acid, 1,2,4-benzenetricarboxylic acid, 1,
2,5-benzenetricarboxylic acid, 1,2,4-cyclohexanetricarboxylic acid, 1,2,5-cyclohexanetricarboxylic acid, 1,2,4-butanetricarboxylic acid,
1,3-Dicarboxy-2-methyl-2-methylcarboxypropanetetra (methylcarboxy) methane can be used. In synthesizing the polyester, a plurality of types of polyol components and dicarboxylic acid components may be mixed and used. A plurality of polyesters can be used in combination in the toner.

In the present invention, the acid value of the polyester is adjusted to 15 to 50, preferably 20 to 40. When the acid value is less than 15, the dispersibility of the anti-offset agents 1 and 2 decreases, and when it is more than 50, the environmental stability of the charge amount of the toner decreases.

The acid value can be adjusted by adjusting the ratio between the polyol component and the carboxylic acid component constituting the polyester resin.

The anti-offset agent 1 used in the present invention has a softening point of 60 such as carnauba wax, sasol wax, rice wax, candelilla wax, jojoba oil wax, beeswax wax, and oxidized polyethylene wax.
Acid value ~ 108 ° C. is 3 to 45, preferably to use a 3 to 35.

The anti-offset agent 2 used in the present invention may be an oxidized polyethylene wax or an oxidized polypropylene wax having a softening point of 115 to 150 ° C. and an acid value of 1 to 30, preferably 2 to 20. it can.

The amount of the anti-offset agent to be added is 1 to 100 parts by weight of the toner resin.
6 parts by weight, preferably 2 to 5 parts by weight, and 0.5 to 5 parts by weight, preferably 1 to 3 parts by weight, of the anti-offset agent 2 with respect to 100 parts by weight of the toner resin. The total amount of the agent is 2 to 7 parts by weight, preferably 3 to 5 parts by weight, based on 100 parts by weight of the toner resin. If the amount is less than 2 parts by weight, the effect of preventing the offset becomes insufficient, and if it is more than 7 parts by weight, the fluidity of the toner deteriorates.

The anti-offset agent 1 is replaced with the anti-offset agent 2
It is desirable to add more in terms of low-temperature fixability and prevention of offset during low-temperature fixation. In this case, the acid value of the anti-offset agent 1
It is preferable from the viewpoint of dispersibility that the acid value is larger than the acid value of the above.

The toner of the present invention can be mixed and kneaded by a conventionally known method, for example, by adding a predetermined amount of a colorant, a charge control agent and other desired additives in addition to the binder resin and the anti-offset agent. After that, it is obtained by crushing and classifying.

The colorant used in the present invention is not particularly limited, and a colorant conventionally used in electrophotography can be used, and examples thereof include the following. First, black pigment as a colorant, carbon black, copper oxide,
Manganese dioxide, aniline black, activated carbon, ferrite, magnetite and the like can be used. As a yellow pigment, graphite, zinc yellow, cadmium yellow, yellow iron oxide, mineral fast yellow, nickel titanium yellow, navels yellow, naphthol yellow S,
Bunzer Yellow G, Bunzer Yellow 10G, Benzidine Yellow G, Benzidine Yellow GR, Quinoline Yellow Lake, Permanent Yellow NCG, Tartrazine Lake and the like can be used.

Examples of the red pigment include red lead, molybdenum orange, permanent orange GTR, pyrazolone orange, vulcan orange, indasrene brilliant orange RK, benzidine orange G, indasrene brilliant orange GK, bengala, cadmium red, and leadtan. , Permanent Red 4R, Risor Red, Pyrazolone Red, Watching Red, Lake Red C, Lake Red D, Brilliant Carmine 6B,
Eosin Lake, Rhodamine Lake B, Alizarin Lake, Brilliant Carmine 3B, Permanent Orange GTR, Vulcan Fast Orange GG, Permanent Red F4RH, Permanent Carmine FB and the like can be used. As the blue pigment, navy blue, cobalt blue, alkali blue lake, Victoria blue lake, phthalocyanine blue, and the like can be used. The amount of these colorants is 1 to 20 parts by weight, preferably 3 to 15 parts by weight, based on 100 parts by weight of the resin in the toner.

A charge control agent generally used in conventional dry developers may be used if necessary. Examples of the negative charge control agent include chromium complex salt type azo dyes, copper phthalocyanine dyes, chromium complex salts, and the like. Zinc complex salts, aluminum complex salts, fluorinated quaternary ammonium salts and the like can be used. The charge control agent is used in an amount of 0.5 to 8 parts by weight, preferably 1 to 5 parts by weight, based on 100 parts by weight of the resin in the toner. The toner of the present invention may further contain a fluidizing agent and a resin bead as a cleaning aid, if necessary.

When a fluidizing agent is used, silica fine particles, titanium dioxide fine particles, alumina fine particles, magnesium fluoride fine particles, silicon carbide fine particles, boron carbide fine particles, titanium carbide fine particles, zirconium carbide fine particles, boron nitride fine particles, titanium nitride fine particles , Zirconium nitride fine particles, magnetite fine particles, molybdenum disulfide fine particles,
Fine particles of aluminum stearate, fine particles of magnesium stearate, fine particles of zinc stearate and the like can be used. These fine particles are desirably used after being subjected to a hydrophobic treatment with a silane coupling agent, a titanium coupling agent, a higher fatty acid, silicone oil, or the like. The amount of the fluidizing agent is 0.05 to 5 parts by weight, preferably 0.1 to 3 parts by weight, based on 100 parts by weight of the toner.

In addition, emulsion polymerization, soap-free emulsion polymerization,
Various organic fine particles such as styrene, acrylic, methacrylic, benzoguanamine, silicone, Teflon, polyethylene and polypropylene granulated by a wet polymerization method such as non-aqueous dispersion polymerization or a gas phase method may be used alone or in combination. it can.

The toner of the present invention is applied to, for example, a non-magnetic one-component developing device having a schematic structure shown in FIG. In this apparatus, the regulating member is pressed against the surface of the toner carrier (toner sleeve) to regulate the amount of toner on the surface of the toner carrier, and frictionally charges the toner supplied to the surface of the toner carrier. The toner is supplied from the toner carrier to the photoconductor. In FIG. 1, the non-magnetic one-component developing device includes a driving roller 1 which is driven to rotate counterclockwise in FIG. 1 by driving means (not shown). The driving roller has an inner diameter slightly larger than the outer diameter of the roller. Flexible developing sleeve 2 (endless,
Film). Both ends of the developing sleeve 2 are pressed against the driving roller 1 from behind by a pressing guide 3, while the slack portion 1 formed on the opposite side by the pressing is provided.
0 is in flexible contact with the electrostatic latent image carrier (photosensitive drum) PC. Further, a toner regulating blade 4 is in contact with the developing sleeve 2 from the same side as the pressing guide 3.

Behind the developing sleeve 2, a buffer chamber 5 is provided.
The toner supply chamber 6 is further provided behind the toner supply chamber 6, and the toner supply rotation member 7 (counterclockwise rotation) is provided in the buffer chamber 5.
The toner supply chamber 6 is provided with a toner stirring / supply rotation member 8 (clockwise CW rotation). Further, a lower seal member 9 for preventing toner from leaking from the buffer chamber 5 to the outside is in contact with the lower surface of the developing sleeve 2.

According to this developing device, the non-magnetic one-component toner T sent from the toner supply chamber 6 to the buffer chamber 5 by the rotation of the rotating member 8 is sequentially deposited on the surface of the developing sleeve 2 by the rotation of the toner supply rotating member 7. Supplied. On the other hand, the developing sleeve 2 is driven to rotate by the frictional force with the driving rotation of the driving roller 1, and the toner T
Is triboelectrically charged under the pressure of the blade 4 by passing between the toner regulating blade 4 and the sleeve 2 to form a thin layer having a predetermined thickness. This thin toner layer is applied to the developing sleeve 2
Is transported to a developing area facing the photosensitive drum PC, and is used for developing an electrostatic latent image. Excess toner remaining on the sleeve 2 after the development is returned to the buffer chamber 5 through the space between the seal member 9 and the developing sleeve 2 as the sleeve 2 rotates.

Although an example of the non-magnetic one-component developing apparatus using the non-magnetic one-component toner of the present invention has been described above, the present invention is not limited to this. For example, in the developing device shown in FIG. 1, a developing sleeve 2 whose inner diameter is larger than the outer diameter of the driving roller and in which a slack portion 10 is formed is used. A developing sleeve having an inner diameter equivalent to the outer diameter of the driving roller can also be used.

The toner of the present invention is not limited to a non-magnetic one-component toner, but is also applicable as a magnetic one-component toner or a two-component toner. The toner of the present invention can be applied to an image forming apparatus provided with a fixing device equipped with a small fixing roller pair having a roller diameter of 25φ or less, preferably about 10 to 20φ, and a spring pressure of 3.0 kg to 6 kg. .0k
Adjustable during g. Paper passing property at 6.0kg or more
(Paper jams and paper wrinkles), and if the weight is 3.0 kg or less, there is a problem in fixing strength and the like.

[0027]

EXAMPLES Example 1 (1) Synthesis of Low-Molecular-Weight Polyester Resin A 5-liter four-necked flask equipped with a reflux condenser, a water separator, a N ₂ gas inlet tube, and a stirrer was installed in a mantle heater. The flask was charged with 1376 g of a bisphenol propylene oxide adduct and 443 g of isophthalic acid, and 220 to ₂ g of N ₂ gas was introduced into the flask.
Dehydration polycondensation was performed at 70 ° C. to obtain a low molecular weight polyester resin (Mw: 4000, Tg: 58 ° C.).

(2) Synthesis of High-Molecular-Weight Polyester Resin A 5-liter 4-neck flask equipped with a reflux condenser, a water separator, an N ₂ gas inlet tube, and a stirrer, and a mantle heater were installed. 1,720 g of bisphenol propylene oxide adduct, 1028 g of isophthalic acid,
328 g of 1,6-dipropyl-1,6-hexanediol,
74.6 g of glycerin was charged and subjected to dehydration polycondensation at 240 ° C. while introducing N ₂ gas into the flask to obtain a high molecular weight polyester resin (Mw: 6800, Tg: 38 ° C.).

80 parts by weight of the polyester resin for low molecular weight and 20 parts by weight of polyester resin for high molecular weight are charged into a Henschel mixer and dry-blended until sufficiently uniform, and then diphenylmethane-4,4 is heated by a kneader.
40 parts by weight of diisocyanate were charged and reacted at a temperature of 120 ° C. for 1 hour, the softening point was 110 ° C., and the glass transition point (T
g) A urethane-modified polyester resin having an acid value of 28 at 59 ° C was obtained. The ester resin was used as a binder resin for a toner.

(3) Production of Toner * Urethane-modified polyester resin 100 parts by weight * Carbon black (Mogal L; manufactured by Cabot) 5 parts by weight * Charge control agent (S-34 (trade name; manufactured by Orient Chemical Co.) 2 weights) Parts * Offset preventive agent 1 (carnauba wax, acid value 4, softening point 85 ° C, manufactured by Kato Yoko Co., Ltd.) 1.5 parts by weight * Offset preventive agent 2 (Viscol TS-200; softening point 145 ° C, acid value 3.5) 1.0 parts by weight The above composition was mixed and dispersed with a Henschel mixer.
The mixture was kneaded with a twin screw extruder. Thereafter, the kneaded material is cooled and coarsely pulverized, and then finely pulverized using a fine pulverizer such as a jet mill,
Next, the finely pulverized product was classified by an air classifier to obtain particles having an average particle size of 8.6 μm (3.8% of 5 μm or less, 0% of 20 μm or more). Further, hydrophobic silica H-2000 is added to the particles.
(Available from Hoechst) was added in an amount of 0.5% by weight and treated with a Henschel mixer at 2500 rpm for 60 seconds to obtain toner particles A.

Continuous Print Test Next, the toner particles were set in a printer SP-1000 (manufactured by Minolta) equipped with a Teflon-coated roller as a fixing roller, and a continuous print test was performed at a fixing temperature of 130 ° C. 6,000 from the beginning without causing roller dirt and winding phenomenon
Good image quality was obtained up to one sheet.

The printing durability was evaluated for image density, fog and filming. The image density was measured using a Sakura Densitometer (manufactured by Konica Corporation) and ranked as follows. ：: image density of 1.40 or more; Δ: image density of 1.35 to less than 1.40; ×: image density of less than 1.35; −: measurement was not possible due to occurrence of offset. ○ or higher is desirable, but there is no practical problem with a rank of or higher.

For fog, images were visually evaluated and ranked as follows. ：: no fogging; Δ: slight fogging but no practical problem; ×: fogging and practical problem; −: no evaluation due to offset .

In the filming, the surface of the developing sleeve was visually evaluated and ranked as follows. ：: Filming has not occurred; Δ: Filming has occurred slightly but has no practical problem; X: Filming has occurred and there is a practical problem; −: Offset has occurred and measured. could not.

The printer SP-
The 1000 fixing device was equipped with an upper roller of 20φ (Teflon resin collate) and a lower roller of 20φ (silicone rubber), and the spring pressure was set to 4.5 kg.

Further, the non-offset region and the fixing strength were evaluated, and the results are shown in Table 2. Non-offset range: Roller set temperature 90 to 2 every 5 ° C
The temperature was changed to 30 ° C. to fix the toner image, and the temperature range in which no offset occurred was determined. Non-offset area is 1
In the case of fixing at 30 ° C., there is no practical problem if it is 130 ° C. ± 20 ° C. In the case of fixing at 170 ° C., there is no practical problem if it is 170 ± 20 ° C.

Fixing strength: The toner image is fixed by setting the roller temperature to 130 ° C., and the image density (ID) is 1.
As shown in FIG. 2, an eraser was applied to the portion in the range of 35 to 1.45, and after three reciprocations, the ID was measured and the fixing strength was calculated by the following equation. The fixing strength needs to be 85% or more.

(Equation 1)

The non-offset width and printing durability evaluated by the fixing test are shown in Tables 1 and 2 below.

Example 2 A toner particle B was obtained in the same manner as in Example 1 except that the offset preventing agent was changed as follows. * Offset preventive agent 1 (rice wax No. 1, softening point: 82 ° C, acid value: 7, manufactured by Noda Wax Co.) 2.0 parts by weight * Offset preventive agent 2 (Viscol TS-200, softening point: 145 ° C, (Acid value: 3.5; manufactured by Sanyo Chemical Co., Ltd.) 1.5 parts by weight Toner particles B were evaluated in the same manner as in Example 1.
The non-offset width and printing durability are shown in Tables 1 and 2 below.

Example 3 A toner particle C was obtained in the same manner as in Example 1 except that the offset preventing agent was changed as follows. * Offset preventive agent 1 (Sasol wax A7, softening point: 90 ° C, acid value: 27, manufactured by Kato Yoko Co., Ltd.) 2.0 parts by weight * Offset preventive agent 2 (Hoechst wax PED121, softening point: 115 ° C, acid value) : 17; manufactured by Hoechst Co.) 1.0 part by weight The same evaluation as in Example 1 was performed for toner particles C.
The non-offset width and printing durability are shown in Tables 1 and 2 below.

Example 4 (1) Synthesis of Polyester A 5-liter four-necked flask was equipped with a reflux condenser, a water separator,
An N ₂ gas introduction pipe and a stirrer were attached and installed in a mantle heater. The flask was charged with 200 g of a bisphenol ethylene oxide adduct, bisphenol propylene oxide 490, and terephthalic acid, and subjected to a dehydration polycondensation reaction while maintaining the temperature at 200 ° C. while introducing N ₂ gas into the flask. Thereafter, 120 g of anhydrous 1,2,4-benzenetricarboxylic acid was added and further reacted to obtain a polyester resin (softening point: 121 ° C., Tg: 63 ° C., acid value: 38).
This was used as the following binder resin for toner.

(2) Production of Toner * 100 parts by weight of the above polyester resin * 5 parts by weight of carbon black (Mogal L; manufactured by Cabot Corporation) * 3 parts by weight of charge control agent (E-81; manufactured by Orient Chemical Company) * Offset Inhibitor 1 (high wax 4202E; softening point: 108 ° C, acid value: 16, manufactured by Mitsui Petrochemical Co.) 1.0 part by weight * Offset inhibitor 2 (TS-200B, softening point: 136 ° C, acid value: 5) 2.9, manufactured by Sanyo Chemical Industries) 3.0 parts by weight Toner particles D were obtained in the same manner as in Example 1. Next, the toner particles D were evaluated in the same manner as in Example 1. The non-offset width and printing durability are shown in Tables 1 and 2 below.

Comparative Example 1 Toner particles E were obtained in the same manner as in Example 1 except that the offset preventing agent 2 was not added. Next, the toner particles E were evaluated in the same manner as in Example 1. The non-offset width and printing durability are shown in Tables 1 and 2 below.

Comparative Example 2 Toner particles F were obtained in the same manner as in Example 1, except that the offset preventing agent 1 was not added. Next, the toner particles F were evaluated in the same manner as in Example 1. The non-offset width and printing durability are shown in Tables 1 and 2 below.

Comparative Example 3 In Example 1, Viscol 550P (manufactured by Sanyo Chemical Industries, Ltd.) was used in place of the offset inhibitor 2, softening point: 145 ° C.
Toner particles G were obtained in the same manner except that acid value: 0 was used. Next, the toner particles G were evaluated in the same manner as in Example 1. Table 1 and Table 2 below show the non-offset width and printing durability.
Shown in

Comparative Example 4 In Example 3, Sasol wax H1 (manufactured by Kato Yoko Co., Ltd.) was used in place of the offset inhibitor 1, softening point: 108
° C and an acid value of 0.
I got Next, the toner particles H were evaluated in the same manner as in Example 1. The non-offset width and printing durability are shown in Tables 1 and 2 below.

Comparative Example 5 In Example 3, high wax 110 (manufactured by Mitsui Petrochemical Co., Ltd.) was used instead of offset inhibitor 1, softening point: 110
C., acid value: 0, toner particles I were obtained in the same manner except that high wax 400, softening point: 132.degree. Next, the toner particles I
Was evaluated in the same manner as in Example 1. The non-offset width and printing durability are shown in Tables 1 and 2 below.

[0048]

When the toner of the present invention is used, good fixing is possible over a wide temperature range from a low temperature region (around 130 ° C.) to a high temperature region (around 170 ° C.), no offset is observed, and printing durability is not observed. The nature was also excellent.

[0049]

[Table 1]

[0050]

[Table 2]

[Brief description of the drawings]

FIG. 1 is a diagram showing a schematic configuration of a one-component developing device.

FIG. 2 is a diagram for explaining a method for measuring fixing strength.

[Explanation of symbols]

1: Drive roller 2: Developing sleeve 3: Press guide 4: Toner regulating blade 5: Buffer chamber 6: Toner supply chamber 7: Toner supply rotating member 8: Toner stirring / rotating member 9: Lower seal member 10: Slack of developing sleeve Part T: toner PC: electrostatic latent image carrier (photosensitive drum)

──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Tsutsui's main tax Osaka International Building Minolta Co., Ltd. 2-3-13 Azuchicho, Chuo-ku, Osaka, Osaka (72) Inventor Masaaki Takama Azuchi, Chuo-ku, Osaka, Osaka 2-3-1, Machimachi, Osaka International Building Minolta Co., Ltd. (56) References JP-A-3-168652 (JP, A) JP-A-59-129863 (JP, A) JP-A-6-130714 (JP, A) A) JP-A-4-358159 (JP, A) JP-A-63-108357 (JP, A) JP-A-6-266156 (JP, A) JP-A-60-252365 (JP, A) JP-A-6060 JP-A-3-252865 (JP, A) JP-A-3-168865 (JP, A) JP-A-6-250442 (JP, A) JP-A-5-232743 (JP, A) JP-A-6-273976 (JP, A) JP-A-3-2874 (JP, A) JP-A-5-341577 ( P, A) (58) investigated the field (Int.Cl. ^7, DB name) G03G 9/08

Claims (4)

(57) [Claims] An acid value of at least 15 to 50, comprising at least a binder resin, two kinds of anti-offset agents and a colorant, wherein the binder resin comprises at least a polyester resin containing etherified diphenol and dicarboxylic acid as main components. a resin, a softening point of 60 to 108 ° C. in an offset inhibitor 1, acid value in 3 to 45,
The softening point of the offset preventing agent 2 115 to 150 DEG ° C., an acid number from 1 to 30
Yes, anti-offset agent 1 is carnauba wax, Sazo
Wax, rice wax, candelilla wax,
Jojoba oil wax, beeswax wax and oxidized polye
Anti-offset agent 2 selected from Tylene wax
Polyethylene wax and oxidized polypropylene
A toner for electrostatic charge development, wherein the toner is selected from wax . 2. The offset inhibitor 1 is added in an offset amount.
Claim 1 characterized in that it is larger than the added amount of the antioxidant 2
The electrostatic charge developing toner described above. 3. The acid value of the offset inhibitor 1 is offset.
Claim 2 wherein the acid value of the inhibitor 2 is larger than
For electrostatic charge development. 4. The electrostatic charge developing toner according to claim 1, wherein the toner is a non-magnetic one-component developing method toner.