JP2002091068A - Electrostatic charge image developing toner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a new electrostatic charge image developing toner such that good color reproducibility is obtained even when master batch of a coloring agent is not used, uniform toner layer can be formed on a developing sleeve, proper gloss can be easily controlled, good low temperature fixing property is obtained, melt sticking on the developing sleeve or on a blade, splashing of the toner, fog or the like is prevented even for long-term continuous copying, and stable image characteristics can be obtained. SOLUTION: The electrostatic charge image developing toner contains a binder resin, coloring agent and dispersant, where the binder resin contains at least crosslinked polyester resin or/and polyether polyol resin.

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 an electrophotographic copying machine and an electrophotographic printer, and more particularly to an electrostatic charge developing toner useful in a non-magnetic one-component developing method.

[0002]

2. Description of the Related Art Conventionally, as a developing method used in electrophotography, there are a two-component developing method and a one-component developing method.
The above-described two-component developing method refers to an insulating fine powder containing a binder resin as a main component, that is, an insulating toner and a magnetic carrier, which are charged by friction to form a magnetic brush, and an electrostatic formed on a photoreceptor. This is a method of developing a latent image. The one-component developing method can be further divided into a magnetic one-component developing method and a non-magnetic one-component developing method. The magnetic one-component developing method is a method of developing with an electrostatic developing toner containing a magnetic powder, and the non-magnetic one-component developing method is a method in which an electrostatic developing toner not containing a magnetic powder is placed on a developing sleeve. This is a method of forming a thin layer and developing it in contact with or non-contact with a photoreceptor.

In the non-magnetic one-component method, in order to obtain a good visible image, it is necessary to impart a sufficient amount of charge to the toner for electrostatic charge development similarly to the two-component developing method.
In addition, it is indispensable to uniformly control the thickness of the electrostatic charge developing toner on the developing sleeve. at present,
In order to provide a sufficient charge amount or to uniformly control the thickness of the toner, a rubber or metal layer regulating member is often pressed against the developing sleeve. In addition, the electrostatic charge developing toner used in the conventional non-magnetic one-component method mainly includes a binder resin such as a styrene-acrylic copolymer resin and a colorant, and further includes a charge control such as a gold-containing azo dye. A technique has been proposed in which a relatively high charge is imparted by incorporating an agent.

However, in the conventional electrostatic developing toner, when the pressing force to the layer regulating member provided so as to press against the developing sleeve is low, the charge is not sufficiently applied to the toner, while the pressing force is reduced. When the height is increased, the surface of the blade member and the developing sleeve become significantly worn during repeated development, and irregularities are generated on those surfaces.When the toner passes between the blade member and the developing sleeve due to the irregularities, The phenomenon that the applied force becomes non-uniform or the toner layer on the developing sleeve is partially thickened occurs.
As a result, the amount of charge required by the toner is insufficient, and there is a problem that density unevenness and fog occur on an image. In particular, in the non-contact developing method, a problem occurs in that toner flies from the developing sleeve to the photoreceptor during continuous copying, and the developing characteristics are apt to deteriorate. Further, in the conventional electrostatic charge developing toner, a phenomenon in which the toner is fused to the developing sleeve by pressing force or heat, that is, a problem of so-called developing sleeve fusion may occur.

On the other hand, in recent years, there has been an increasing need for full-color image output. To improve the image quality of an electrostatic charge developing toner used for the purpose, it is necessary to impart some gloss to the image surface. In order to obtain gloss, the image surface needs to be moderately smooth. In this case, it is necessary that the resin used for the electrostatic charge developing toner be rapidly melted in the fixing process and spread smoothly. Such an electrostatic charge developing toner which is easily melted by heat generally has a low mechanical strength, and has a problem that it is easily fused to members such as a layer regulating member and a developing sleeve used in the non-magnetic one-component developing method. there were. In addition, in the case of a full-color toner, it is difficult to disperse a pigment-based colorant. Conventionally, a masterbatch in which a colorant is preliminarily dispersed in a binder resin in a high content is generally used. . When using the same method,
The production cost is high, and the molecular chains of the resin are easily cut, and the resulting low-molecular-weight resin becomes a component that is easily fused to members such as a layer regulating member and a developing sleeve, and the non-magnetic one component There has been a problem in that sleeve fusion, which is a problem in the developing method, is likely to occur.

[0006]

The present invention provides good color reproducibility without using a colorant masterbatch,
A uniform toner layer can be obtained on the developing sleeve, moderate glossiness can be easily adjusted, low-temperature fixability is good, and fusing on the developing sleeve and blade, toner scattering, fogging, etc. in long-term continuous copying It is an object of the present invention to provide a novel toner for electrostatic charge development that does not have any problems and can realize stable image characteristics.

[0007]

SUMMARY OF THE INVENTION The present invention relates to a toner for developing an electrostatic charge, comprising at least a binder resin containing a crosslinked polyester resin and / or a polyether polyol resin, a colorant and a dispersant. is there.

[0008]

DETAILED DESCRIPTION OF THE INVENTION The crosslinked polyester resin used in the present invention is not particularly limited, but is a mixture of a divalent carboxylic acid, a dihydric alcohol, a trivalent or higher polycarboxylic acid and / or a trivalent or higher alcohol. It can be obtained by condensation. Examples of the divalent carboxylic acid include aliphatic dibasic acids such as malonic acid, succinic acid, mazeleiic acid, sebacic acid, hexahydrophthalic anhydride, phthalic anhydride, phthalic acid, and the like.
Aromatic dibasic acids such as terephthalic acid and isophthalic acid, and alkyl or alkenyl succinic acids having a hydrocarbon group having 4 to 35 carbon atoms in the side chain such as isododecenyl succinic acid and n-dodecenyl succinic acid, and lower alkyls thereof. Examples thereof include esters and halides.

Examples of the dihydric alcohol include ethylene glycol, 1,2-propylene glycol,
3-propylene glycol, 1,2-butanediol,
1,3-butanediol, 1,4-butanediol,
1,6-hexanediol, neopentyl glycol,
Examples thereof include diethylene glycol, dipropylene glycol, cyclohexane dimethanol, hydrogenated bisphenol A, bisphenol A ethylene oxide adduct, bisphenol A propylene oxide adduct, polypropylene glycol, and polytetramethylene glycol. Examples of the trivalent or higher polycarboxylic acid include 1,2,4-butanetricarboxylic acid and 1,2,5-
Hexanetricarboxylic acid, 1,3-dicarboxyl-2
Aliphatic polycarboxylic acids such as -methyl-2-methylenecarboxypropane, tetra (methylenecarboxyl) methane, 1,2,7,8-octanetetracarboxylic acid,
Alicyclic polycarboxylic acids such as 1,2,4-cyclohexanetricarboxylic acid, 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, 2,5,7
And aromatic polycarboxylic acids such as -naphthalenetricarboxylic acid and 1,2,4-naphthalenetricarboxylic acid, pyromellitic acid and benzophenonetetracarboxylic acid, and anhydrides and lower alkyl esters thereof.

Examples of the trivalent or higher alcohol include, for example,
Sorbitol, 1,2,3,6-hexanetetraol, 1,4-sorbitan, pentaerythritol, dipentaerythritol, tripentaerythritol, 1,
Aliphatic polyvalents such as 2,4-butanetriol, 1,2,5-pentanetriol, glycerol, 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, and trimethylolpropane Examples thereof include alcohols, aromatic polyhydric alcohols such as 1,3,5-trihydroxylmethylbenzene, and alkylene oxide adducts thereof. In the crosslinked polyester resin, for the purpose of adjusting the molecular weight and controlling the reaction, monocarboxylic acids, monoalcohols, and the like can be used as necessary together with carboxylic acids and alcohols.

The polyether polyol resin used in the present invention can be produced by reacting a bisphenol type epoxy resin with a compound having active hydrogen that reacts with epoxy. Examples of compounds having active hydrogen that reacts with epoxy include monohydric phenols, dihydric phenols, carboxylic acids, alcohols, and alkylene oxide adducts of dihydric phenols. The polyether polyol resin used in the present invention preferably has a peak top molecular weight (Mp) of 3000 or more in a chromatogram measured by gel permeation chromatography of a tetrahydrofuran-soluble component, more preferably 3200 or more, More preferably, it is 3500 or more. When Mp is less than 3000, the number of low molecules in the oligomer region increases, and the frictional force between the toner and the developing device member easily causes the toner to fuse to the member, which causes problems such as fog and toner scattering. It is not preferable because it occurs. Further, the number average molecular weight (Mn) is preferably 2700 or more, more preferably 3000 or more, and still more preferably 3500 or more. Mn is 270
If it is less than 0, the number of low molecules in the oligomer region increases, and the frictional force between the toner and the developing device member easily causes the toner to fuse to the member, causing problems such as fog and toner scattering. Not preferred.

Usually, when a crosslinked polyester resin having a molecular weight distribution equivalent to that of the polyether polyol resin in the present invention is used for a toner, toner fusion to a developing member may occur. However, the polyether polyol resin used in the present invention does not cause toner fusion. Although the reason for this is not necessarily clear, it is presumed that it is effective that the composition is rich in toughness and high in elasticity as compared with the crosslinked polyester resin. In addition, the high toughness is advantageous also in the fixing property, the non-offset temperature range is wide, the oil amount applied to the fixing sleeve may be small, and in particular,
It has advantages such as little toner peeling when a solid image is bent.

[0013] As described above, the polyether polyol resin has a characteristic that the durability and the fixing property can be compatible with each other as compared with the crosslinked polyester resin. However, a toner using a polyether polyol resin having a high hydroxyl group is inferior in negative chargeability and may cause fogging and toner scattering. Therefore, the hydroxyl value of the resin is 30 mgK.
It is preferably OH / g or less. On the other hand, the crosslinked polyester resin can keep the hydroxyl value low. Using the polyether polyol resin alone, as described above, when problems such as fogging and toner scattering occur, although the compatibility of fixing performance and durability is slightly inferior,
By mixing or using the crosslinked polyester resin of the present invention alone, good charging properties can be obtained, and problems such as fogging and toner scattering can be avoided.

Further, the toner for electrostatic charge development of the present invention includes:
The peak top molecular weight (Mp) is 7000 or more, the number average molecular weight (Mn) is 4500 or more, and Mw / Mn is 2 to 10 in a chromatogram measured by gel permeation chromatography of a tetrahydrofuran-soluble component.
It is preferable to contain the linear polyester resin of the above. As described above, the linear polyester resin has a peak top molecular weight (Mp) of preferably 7000 or more, more preferably 7 or more.
It is 500 or more, more preferably 8000 or more. Mp
Is less than 7000, the number of low molecules in the oligomer region increases, and the frictional force between the toner and the developing device member easily causes the toner to fuse to the member, causing problems such as fog and toner scattering. But not preferred.

The number average molecular weight (Mn) is preferably 4500 or more, more preferably 5000 or more, and further preferably 5500 or more. When Mn is less than 4500, the number of low molecules in the oligomer region increases, and the frictional force between the toner and the developing device member easily causes the toner to fuse to the member, resulting in problems such as fog and toner scattering. It is not preferable because it occurs. The linear polyester resin used in the present invention has a weight average molecular weight (Mw) / number average molecular weight (Mn).
Is preferably 2 to 10, more preferably 2 to 10.
8, more preferably 2 to 5. When Mw / Mn is less than 2, the brittleness of the linear polyester resin is increased, and the linear polyester resin is easily crushed. As a result, the mechanical strength is reduced, the toner particles are broken in the developing device, and an increase in fine powder that does not contribute to development is likely to occur. On the other hand, when the Mw / Mn ratio exceeds 10, the molecular weight distribution is so wide that it becomes difficult to melt by heat, it becomes difficult to impart gloss to the image, and the low-temperature fixability may be impaired. In the present invention, by using the above-mentioned linear polyester resin in combination with a crosslinked polyester resin and / or a polyether polyol resin, the low-temperature fixability and the durability are compatible, and the glossiness of the toner image is reduced. It can be adjusted arbitrarily.

The coloring agents used in the present invention include carbon black, aniline blue, calco oil blue, chrome yellow, ultramarine blue, Dupont oil red, quinoline yellow, methylene blue clesoid, phthalocyanine blue, malachite green oxalate, and lamp. Black, rose bengal, rhodamine dyes or pigments, anthraquinone dyes, monoazo and disazo dyes or pigments and the like are used. In the case of carbon black, the primary particle diameter is preferably 25 to 75 nm, particularly 30 to 55 nm, and the specific surface area is preferably 110 m ² / g or more. When such a carbon black is used, the crushability by melting and kneading and the dispersibility with the material are good. The content of the colorant may be an amount sufficient to color a toner capable of forming a visible image by development.
-20 parts by weight are preferred.

The dispersant used in the present invention is contained in order to uniformly disperse the colorant in the toner particles, and its content is preferably in the range of 0.1 to 3% by weight in the toner. Examples of the dispersant include modified polyurethane, modified polyacrylate, polyetherester-type anionic surfactant, naphthalenesulfonic acid formalin condensate, aromatic sulfonic acid formalin condensate, polyoxyethylene alkyl phosphate, polyoxyethylene nonyl. Phenyl ether, stearylamine acetate, hydroxyl-containing carboxylic acid ester, salt of long-chain polyaminoamide and high molecular weight acid ester, salt of high molecular weight polycarboxylic acid, salt of long-chain polyaminoamide and polar acid ester, high molecular weight unsaturated acid ester , A polymer copolymer, a pigment derivative and the like can be used.

Among these, the number average molecular weight (Mn) is at least 1400 in the chromatogram measured by gel permeation chromatography and the melting point is at least 50 ° C. as measured by a differential calorimeter. Are preferred. When the number average molecular weight (Mn) is less than 1400, or when the melting point is less than 50 ° C., the toner is liable to cause sleeve fusion. Further, the dispersant used in the present invention contains an ester bond in its structure, so that the crosslinkable polyester resin of the dispersant or / and
And the compatibility with the polyether polyol resin can be improved. As a dispersant having an ester bond in such a structure, there is a dispersant obtained by adding an amine to polyester, and as commercial products, Solspers 28000, Solspers 26000, Solspers 24000, and Solspers 13000 (all of which are commercially available from Avicia). Name).

In the present invention, the BET specific surface area is 10
0 m ² / g or more inorganic fine particles and a BET specific surface area of 60 m ²
/ G or less of inorganic particles is preferably adhered to the surface of the toner particles by a stirring means such as a Henschel mixer.
The inorganic fine particles of 100 m ² / g or more are mainly used for imparting fluidity to the toner. Inorganic fine particles having a particle size of 60 m ² / g or less mainly have a high polishing effect and are used for the purpose of preventing fusion of toner particles to a developing sleeve or a blade. By using both of them, it is possible to obtain a stable image in which the fluidity of the toner particles does not decrease and the image density does not decrease even in continuous copying. BET specific surface area is 100m ² / g
When the inorganic fine particles having a BET specific surface area of less than 60 m ² / g are used, sufficient fluidity cannot be obtained, and the image density becomes insufficient. In addition, BET
In the case where a combination of inorganic fine particles having a specific surface area of 100 m ² / g or more and inorganic fine particles having a BET specific surface area of more than 60 m ² / g, a sufficient polishing effect cannot be obtained and toner is fused to a developing sleeve or a blade. There is.

The inorganic fine particles having a BET specific surface area of 60 m ² / g or less are desirably adhered to 2.5 parts by weight or less based on 100 parts by weight of the toner particles. If the amount is more than 2.5 parts by weight, the fluidity may decrease and a sufficient image density may not be obtained. On the other hand, the BET specific surface area is 100 m ²
The amount of the inorganic fine particles of not less than 3 parts by weight per 100 parts by weight of the toner particles is desirable. If the amount is more than 3 parts by weight, the coating of the inorganic fine particles on the toner particles becomes excessive, and the fixability may be reduced.

When the electrostatic charge developing toner of the present invention is used in a non-magnetic one-component developing method and the developing sleeve is made of metal, it is better to use more inorganic fine particles to fuse the toner to the developing sleeve or blade. Is preferable because it can be prevented well. That is, the amount of the inorganic fine particles having a BET specific surface area of 60 m ² / g or less is 0.3 to 2.5 parts by weight based on 100 parts by weight of the toner particles.
BET specific surface area is 100 m ² /
When the inorganic fine particles of g or more are mixed in the range of 0.5 to 3 parts by weight, the durability becomes good. On the other hand, when the developing sleeve is an elastic body such as rubber, the BET specific surface area is 60 m ² /
g or less of inorganic fine particles are mixed in the range of 0.3 to 2 parts by weight with respect to 100 parts by weight of toner particles, and the BET specific surface area is 1
When the inorganic fine particles having a particle size of 00 m ² / g or more are mixed in the range of 0.5 to 2 parts by weight, the durability becomes good. However, the addition amount can be appropriately determined in consideration of the fluidity. Examples of inorganic fine particles having a BET specific surface area of 100 m ² / g or more and inorganic fine particles having a BET specific surface area of 60 m ² / g or less include silica, alumina, titanium oxide, magnetite, zinc oxide,
In addition to silicon carbide, zirconium and the like, compounds with organic substances such as magnesium stearate and zinc stearate can also be suitably used, but are not limited to the compounds exemplified above.

In the present invention, it is preferable that a charge control agent pulverized to a mean particle size of 0.7 μm or less by a wet method is fixed to the surface of the toner particles. The average particle size of a commercially available charge control agent itself is on the order of microns, and is at least about 1 μm. A technique for fixing such a relatively large charge control agent to the surface of toner particles by using a mechanical distorting force by using a hybridizer (manufactured by Nara Machinery Co., Ltd.) or the like is known. However, when such a method is used, most of the charge control agent particles are embedded and fixed on the surface of the toner particles, but the charge control agent particles having an excessively large particle diameter cannot be fixed on the surface of the toner particles. When used, electrophotographic members such as a developing unit and a photoreceptor are contaminated, causing problems such as fogging and toner scattering. In the present invention, as a result of intensive studies to solve such a problem, the wet method, that is, the charge control agent finely pulverized into a submicron region in a solvent in which the charge control agent is wet-dispersed in a media-type fine pulverizing apparatus. It was found that good image characteristics can be obtained by fixing the toner to the surface of the toner particles. In this case, the toner particles may or may not include a charge control agent therein.

The charge control agent finely pulverized by the wet method as described above is mixed with the toner particles in a wet state in a solvent and dried, whereby the charge control agent can be easily dispersed and adhered uniformly to the surface of the toner particles. . Further, the charge control agent finely pulverized by the wet method as described above may be dried once and then mixed with the toner particles. After the charge control agent is dispersed and attached to the surface of the toner particles, the charge control agent can be embedded and fixed to the surface of the toner particles using the above-described hybridizer or Henschel mixer. As aforementioned,
Polyol polyether resins are generally inferior in chargeability, but are not limited to a production method in which a normal charge control agent is included in toner particles, and further, as in the present invention, a charge control agent pulverized to a submicron region. Is embedded and fixed on the surface of the toner particles to improve the chargeability in combination with the combined use with the linear polyester resin. As a result, a very good electrophotographic image free of memory and fog can be obtained.

The electrostatic charge developing toner of the present invention may contain a binder resin described below other than the above-mentioned crosslinked polyester resin and polyether polyol resin. That is, polystyrene, polychlorostyrene, poly-α-
Methylstyrene, styrene-chlorostyrene copolymer,
Styrene-vinyl chloride copolymer, styrene-vinyl acetate copolymer, styrene-maleic acid copolymer, styrene
Propylene copolymer, styrene-butadiene copolymer,
Styrene-vinyl chloride copolymer, styrene-vinyl acetate copolymer, styrene-acrylate copolymer (styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer Copolymer, styrene-octyl acrylate copolymer and styrene-phenyl acrylate copolymer), styrene-methacrylate copolymer (styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene- Octyl methacrylate copolymer and styrene-phenyl methacrylate copolymer), styrene-α
-Styrene resins (homopolymers or copolymers containing styrene or styrene substituents) such as methyl chloroacrylate copolymer and styrene-acrylonitrile-acrylate copolymer, vinyl chloride resin, rosin-modified maleic resin , Phenolic resin, epoxy resin, low molecular weight polyethylene, ionomer resin, polyurethane resin,
Silicone resin, ketone resin, ethylene-ethyl acrylate copolymer, xylene resin, polyvinyl butyral resin and the like can be applied to the present invention. When these resins are contained, the content is preferably the above-mentioned crosslinked polyester resin or /
And from 100 to 100 parts by weight of the polyether polyol resin in total.

The electrostatic charge developing toner of the present invention may contain other additives such as a charge control agent and a release agent. Examples of charge control agents include gold-containing azo dyes, nigrosine dyes, quaternary ammonium salts, triphenylmethane-based control agents, oil-soluble dyes such as oil black, naphthenic acid, salicylic acid, octylic acid, and manganese and cobalt thereof. Metal salts such as iron, zinc, aluminum, and lead; and alkylsalicylic acid metal chelates. Examples of the release agent include polyalkylene wax such as low molecular weight polypropylene and low molecular weight polyethylene, paraffin wax, higher fatty acid, and aliphatic amide. The addition amount is preferably 0.5 to 5 parts by weight based on 100 parts by weight of the resin component. As a method of including a release agent in the toner, there are a method of adding the toner inside the toner and a method of externally adding the toner. The charge control agent may be internally added to the toner. In addition, a higher fatty acid or another metal salt may be appropriately added in order to protect the photoreceptor and prevent deterioration of development characteristics and obtain a high-quality image.

The electrostatic charge developing toner of the present invention is a non-magnetic one-component developing method in which the developing sleeve is made of a metal such as aluminum, or a non-magnetic one in which the developing sleeve is made of a material having elasticity other than a metal such as urethane rubber. It can be suitably used for a one-component developing method. An example of such a non-magnetic one-component developing method is described in, for example, JP-A-10-221949.
Japanese Patent Application Laid-Open No.
And a non-contact developing method described in JP-A-160287.

[0027]

The present invention will be described in more detail with reference to the following Examples and Comparative Examples. In the following examples, "parts" means "parts by weight".
Means <Example 1> 30 parts of polyether polyol resin (trade name: TPO-067, Mp: 3300, Mn: 3050, manufactured by Mitsui Chemicals) 70 parts of linear polyester resin (trade name: XPE-2285, manufactured by Mitsui Chemicals, Inc.) , Mp: 11000, Mn: 4800, Mw / Mn: 2)-Phthalocyanine pigment 6 parts (Dainippon Ink & Chemicals, Inc .: KET Blue 104)-Dispersant 0.6 part (Abisia Corp .: Solspers) 24000, Mn: 1700, melting point: 56 ° C) 1 part of gold-containing azo dye (trade name: Bontron E-89 manufactured by Orient Chemical Co.) 2 parts of polyethylene wax (trade name: PE-190 manufactured by Clariant) The materials were mixed with a Henschel mixer, kneaded with an extruder, and finely pulverized with a jet mill to obtain toner particles. For 100 parts of the obtained toner particles, silica fine particles (trade name: NAX50, B manufactured by Nippon Aerosil Co., Ltd.)
0.5 parts of ET specific surface area: 50 m ^{2 /} g) and silica fine particles (trade name: H-2000, manufactured by Clariant, BET)
(Specific surface area: 130 m ^{2 /} g) 0.7 part was mixed with a Henschel mixer to obtain a toner for electrostatic charge development of the present invention having a volume average particle diameter of 9.7 μm.

Example 2 In Example 1, 30 parts of the polyether polyol resin was replaced with a crosslinked polyester resin (trade name: XPE-1954, manufactured by Mitsui Chemicals, Inc., Mp: 5).
(400, Mn: 3500) A toner for electrostatic charge development of the present invention was obtained in the same manner as in Example 1 except that 30 parts was used. The volume average particle diameter of the electrostatic charge developing toner was 9.7 μm.

Example 3 An electrostatic charge developing toner of the present invention was obtained in the same manner as in Example 1 except that 30 parts of the polyether polyol resin was replaced with the following resin. The volume average particle diameter of the electrostatic charge developing toner is 9.
It was 5 μm.・ 15 parts of polyether polyol resin (trade name: TPO-067, Mp: 3300, Mn: 3050, manufactured by Mitsui Chemicals) ・ 15 parts of cross-linked polyester resin (trade name: XPE-1954, Mp: 5400, manufactured by Mitsui Chemicals, Inc.) Mn: 3500)

Example 4 In Example 1, 30 parts of the polyether polyol resin and 70 parts of the linear polyester resin were replaced with a crosslinked polyester resin (trade name: XPE-1954, manufactured by Mitsui Chemicals, Inc., Mp: 5400, Mn: 35).
00) A toner for electrostatic charge development of the present invention was obtained in the same manner as in Example 1 except that the amount was changed to 100 parts. The volume average particle diameter of the electrostatic charge developing toner was 9.3 μm.

Example 5 Toner particles were obtained in the same manner as in Example 1. Next, with respect to 100 parts of the obtained toner particles, a gold-containing azo dye (trade name, manufactured by Orient Chemical Co., Ltd.) previously ground to an average particle size of 0.5 μm by a media grinder.
After mixing 0.5 part of Bontron E-89 with a Henschel mixer, the gold-containing azo dye was fixed to the surface of the toner particles using a hybridizer (manufactured by Nara Machinery Co., Ltd.). The two kinds of silica fine particles were mixed with a Henschel mixer to obtain a toner for electrostatic charge development of the present invention. The volume average particle diameter of this electrostatic charge developing toner is 9.2.
μm.

Comparative Example 1 In Example 1, 30 parts of the polyether polyol resin and 70 parts of the linear polyester resin were replaced with a linear polyester resin (trade name: XPE-1998, manufactured by Mitsui Chemicals, Inc., Mp: 6600, Mn: 340).
0, Mw / Mn: 2) A comparative electrostatic charge developing toner was obtained in the same manner as in Example 1 except that 100 parts was used and the dispersant was omitted. The volume average particle diameter of the electrostatic charge developing toner was 8.5 μm.

Comparative Example 2 In Example 1, 30 parts of the polyether polyol resin and 70 parts of the linear polyester resin were replaced with a linear polyester resin (trade name: XPE-2176, manufactured by Mitsui Chemicals, Mp: 6300, Mn: 320).
0, Mw / Mn: 2) A comparative electrostatic charge developing toner was obtained in the same manner as in Example 1 except that 100 parts was used and the dispersant was omitted. The volume average particle diameter of the electrostatic charge developing toner was 9.7 μm.

Comparative Example 3 In Example 1, 30 parts of the polyether polyol resin and 70 parts of the linear polyester resin were replaced with a linear polyester resin (trade name: XPE-2372, manufactured by Mitsui Chemicals, Inc., Mp: 6300, Mn: 370).
0, Mw / Mn: 2) A comparative electrostatic charge developing toner was obtained in the same manner as in Example 1 except that 100 parts was used and the dispersant was omitted. The volume average particle diameter of the toner for electrostatic charge development was 8.9 μm.

Comparative Example 4 In Example 1, 30 parts of the polyether polyol resin and 70 parts of the linear polyester resin were replaced with a linear polyester resin (trade name: XPE-2285, manufactured by Mitsui Chemicals, Inc., Mp: 11000, Mn: 48).
(00, Mw / Mn: 2) A comparative toner for developing electrostatic charge was obtained in the same manner as in Example 1, except that 100 parts was used. The volume average particle diameter of the electrostatic charge developing toner was 9.6 μm.

Comparative Example 5 A comparative electrostatic charge developing toner was obtained in the same manner as in Example 2 except that the dispersant was omitted. The volume average particle diameter of the electrostatic charge developing toner was 9.2 μm.

Comparative Example 6 A resin and a pigment having the following mixing ratios were kneaded with a twin-screw kneader, and then roughly ground using a hammer mill to prepare a master batch of a cyan pigment. -21 parts of polyether polyol resin (trade name: TPO-067, Mp: 3300, Mn: 3050, manufactured by Mitsui Chemicals)-49 parts of linear polyester resin (trade name: XPE-2285, Mp: 11000, manufactured by Mitsui Chemicals, Inc.) Mn: 4800, Mw / Mn: 2) 30 parts of phthalocyanine pigment (trade name: KET Blue 104, manufactured by Dainippon Ink and Chemicals, Inc.) Next, the following materials not containing a dispersant are mixed with a Henschel mixer and then extruded. And finely pulverized with a jet mill to obtain toner particles.・ 25.8 parts of polyether polyol resin (trade name: TPO-067, Mp: 3300, Mn: 3050, manufactured by Mitsui Chemicals) ・ 60.2 parts of linear polyester resin (trade name: XPE-2285, manufactured by Mitsui Chemicals, Inc.) Mp: 11000, Mn: 4800, Mw / Mn: 2)-20 parts of the above masterbatch-1 part of a gold-containing azo dye (trade name: Bontron E-89 manufactured by Orient Chemical Co.)-2 parts of polyethylene wax (manufactured by Clariant) Next, 100 parts of the toner particles obtained above were mixed with silica fine particles (trade name: NAX50, manufactured by Nippon Aerosil Co., Ltd.).
0.5 part of BET specific surface area: 50 m ^{2 /} g) and silica fine particles (trade name: H-2000, BE, manufactured by Clariant)
0.7 part (T specific surface area: 130 m ^{2 /} g) was mixed with a Henschel mixer to obtain a comparative electrostatic charge developing toner having a volume average particle diameter of 9.7 μm.

Next, the following evaluation tests were performed on the respective electrostatic charge developing toners of the examples and comparative examples obtained by the above operations. (1) Durability test Table 1 shows the results of the durability test. In the durability test, a sponge containing 100 g of toner in each developing device of a non-magnetic one-component developing device having a developing sleeve made of aluminum and a non-magnetic one-component developing device having a developing sleeve made of urethane rubber was used. The time from the start of stirring to the fusing of the toner to any of the developing sleeve, the layer regulating member, and the stirring member constituting the developing device is described. The stirring time is up to 4 hours.
If there is no toner fusion to the above members even after the elapse of time, the time is described as 4 hours or more. The layer regulating member was made of urethane rubber in the case of an aluminum sleeve, and was made of phosphor bronze in the case of a urethane rubber sleeve.

[0039]

[Table 1]

From the results shown in Table 1, it was confirmed that all of the electrostatic charge developing toners of Examples 1 to 5 of the present invention had good durability. On the other hand, it was confirmed that the electrostatic charge developing toners of all the comparative examples were inferior in durability.

(2) Fixing Test Next, the results of the fixing test are shown in Table 2. The fixing device used had a structure in which a heat fixing roll was formed by coating a cylinder made of aluminum with a fluororesin (trade name: Teflon, manufactured by DuPont) and having a heater lamp inserted inside the cylinder. The pressure roll is made of silicone rubber. First, the fixing test is performed on 2cm x 2cm unfixed paper.
A large number of square solid images are prepared. Next, the surface temperature of the heat fixing roll of the fixing device is set to 130 ° C., and the roll rotation speed is adjusted to 100 mm / sec. Then, the unfixed solid image is bent with its central portion inside, and then passed through the fixing device to be fixed. Next, the square solid image is folded again in the direction perpendicular to the obtained fold,
The fixing is performed again through the fixing device. According to such a fixing method, the unfixed solid image is fixed by changing the surface temperature of the heat fixing roll between 130 ° C. and 220 ° C. at 10 ° C. intervals. Next, a member in which gauze is wound around a flat cylindrical bottom surface having an area of 5 cm ² is slid reciprocally 5 times at a portion where the fold of the fixed square solid image obtained above crosses in the solid image portion. The image density of the solid image before and after sliding in this manner is determined by using Macbeth RD.
Measured at −914, the fixing rate was calculated as to what percentage the image density of the slid solid image had compared to the image density of the solid image before slid, and the fixing temperature at 60% was shown in Table 2. Noted.

[0042]

[Table 2]

As is clear from Table 2, the toner for developing an electrostatic charge of the present invention has a lower fixing temperature for securing a fixing rate of 60% as compared with the toner for developing an electrostatic charge of the comparative example. It was confirmed that it had the property.

(3) Image Characteristics Table 3 shows the results of tests for changes in image characteristics during continuous use. As for the developing device using the aluminum developing sleeve in Table 3, an ipsio 2100 copying machine manufactured by Ricoh Company was used. As for the developing device using a developing sleeve made of urethane rubber, a printer with 2150 multi-writer manufactured by NEC was used. The image density was measured using RD-914 manufactured by Macbeth. Fog was evaluated using a Hunter whiteness meter, and the difference in whiteness between non-image portions before and after imaging was used as an evaluation value.

[0045]

[Table 3]

From the results in Table 3, it can be seen that the electrostatic charge developing toner of the present invention has an image density from the initial stage to 5000 sheets in both the developing device using the aluminum developing sleeve and the developing device using the urethane rubber developing sleeve. , And good image characteristics with little fog were confirmed. Further, as a result of evaluating the initial image, the toner for electrostatic charge development of the present invention was excellent in color reproducibility and glossiness, but Comparative Examples 1 to 4 were inferior in pigment dispersibility and very sharp in color reproducibility. It was confirmed that the image lacked the degree.

[0047]

According to the present invention, a uniform toner layer can be obtained on the developing sleeve, moderate glossiness can be easily adjusted, good low-temperature fixability, and fusion to the developing sleeve and the blade during long-term continuous copying. And a toner for electrostatic charge development which does not cause toner scattering, fogging, etc., and can obtain a large number of stable image characteristics.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G03G 9/08 344

Claims (8)

[Claims] 1. An electrostatic charge developing toner containing at least a binder resin containing a crosslinked polyester resin and / or a polyether polyol resin, a colorant and a dispersant. 2. The polyether polyol resin has a peak top molecular weight (Mp) of 3,000 or more and a number average molecular weight (Mp) in a chromatogram measured by gel permeation chromatography of a tetrahydrofuran-soluble component.
2. The toner according to claim 1, wherein n) is 2700 or more. 3. A chromatogram measured by gel permeation chromatography of a tetrahydrofuran-soluble component having a peak top molecular weight (Mp) of 7000 or more, a number average molecular weight (Mn) of 4500 or more, and Mw
2. The toner according to claim 1, wherein the toner comprises a linear polyester resin having a ratio of / Mn of 2 to 10. 4. The dispersant has a number average molecular weight (Mn) of 1400 or more in a chromatogram measured by gel permeation chromatography and a melting point of 50 ° C. or more measured by a differential calorimeter. 2. The toner according to claim 1, wherein the toner has an ester bond. 5. The toner according to claim 1, wherein inorganic fine particles having a BET specific surface area of 100 m ² / g or more and inorganic fine particles having a BET specific surface area of 60 m ² / g or less are adhered to the surface of the toner particles. For electrostatic charge development. 6. The electrostatic charge developing toner according to claim 1, wherein a charge control agent pulverized to a mean particle diameter of 0.7 μm or less by a wet method is fixed to the surface of the toner particles. 7. The electrostatic charge developing toner according to claim 1, wherein the toner is used in a non-magnetic one-component developing method in which a developing sleeve is made of metal. 8. The electrostatic charge developing toner according to claim 1, wherein the developing sleeve is made of a non-magnetic one-component developing method made of a material having elasticity other than metal.