JP2002023418A - Electrostatic charge image developing toner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrostatic charge image developing toner such that a uniform toner layer can be obtained on a developing sleeve, proper gloss of a toner image can be easily controlled, good low temperature fixing property is obtained, melt sticking of the toner on a developing roll or blade, splashing of the toner and fog are prevented for long-term continuous copying, and stable image characteristics are obtained. SOLUTION: The electrostatic charge image developing toner contains at least a coloring agent, charge controlling agent and crosslinked polyester resin (A) and/or crosslinked polyether polyol resin (B) having >=3,000 peak top mol.wt. (Mp) and >=2,700 number average mol.wt. (Mn) in the chromatogram measured by gel permeation chromatography for the tetrahydrofuran soluble content.

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 for 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, development methods used in electrophotography include a two-component development method and a one-component development method. The two-component developing method refers to an electrostatic latent powder formed on a photoreceptor by forming a magnetic brush by charging an insulating fine powder containing a binder resin as a main component, that is, an insulating toner and a magnetic carrier, by friction. This is a method of developing an 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 a magnetic one-component toner, and the non-magnetic one-component developing method is a method in which a non-magnetic one-component toner is formed in a thin layer on a developing roller and is brought into contact with a photoconductor. Alternatively, a non-contact developing method is used.

In the above-mentioned non-magnetic one-component system, in order to obtain a good visible image, it is necessary to provide a sufficient amount of charge to the non-magnetic one-component developing toner as in the two-component developing system. In addition, it is indispensable to uniformly control the thickness of the non-magnetic one-component developing toner on the developing roller. At present, a rubber or metal layer regulating member is often pressed against a developing roller in order to impart a sufficient charge amount or to uniformly control the thickness of the toner.

A conventional non-magnetic one-component developing toner is
A technology has been proposed in which a binder resin such as a styrene-acrylic copolymer resin and a colorant are used as main components, and a relatively high charge is imparted by incorporating a charge control agent such as a gold-containing azo dye into the resin. I have.

[0005]

However, the conventional non-magnetic one-component developing toner has a blade member while the development is repeatedly performed by a pressing force against a layer regulating member provided so as to press against the developing roller. And the surface of the developing roller is significantly worn, and irregularities are generated on those surfaces.
Due to the unevenness, a phenomenon occurs in which the force applied when the toner passes between the blade member and the developing roller is not uniform, or the toner layer on the developing roller is partially thickened. 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 that toner flies from the developing roller to the photoreceptor at the time of continuous copying occurs, and the developing characteristics are easily deteriorated. Further, in the conventional non-magnetic one-component developing toner, a phenomenon in which the toner fuses to the developing roller by a pressing force or heat, that is, a problem of so-called roller fusion sometimes occurs.

[0006] In recent years, in particular, needs for outputting full-color images have been increasing, but it is necessary to impart a certain degree of gloss to the image surface in terms of image quality. In order to obtain gloss, the image surface needs to be moderately smooth. In this case, in the fixing process, the resin used for the toner needs to be thermally melted quickly and spread smoothly. Such a toner that is easily melted by heat generally has a low mechanical strength and has a problem that it is easily fused to members such as the blade and the developing sleeve.

According to the present invention, a uniform toner layer can be obtained on a developing sleeve, moderate glossiness can be easily adjusted, low-temperature fixability is good, and fusion to a developing roller and a blade in long-term continuous copying is achieved. It is an object of the present invention to provide a novel toner for electrostatic charge development which does not cause toner scattering, fogging and the like and can realize stable image characteristics.

[0008]

Means for Solving the Problems The present inventors diligently studied such a problem, and as a result, have a suitable glossiness, a good low-temperature fixability, and a long-term continuous copying in a non-magnetic one-component developing method. The present invention has been found that, in order to obtain stable developability, by using a toner for electrostatic charge development comprising a specific resin thermal characteristic and a resin composition, fusion of the toner to a developing roller and a blade can be prevented. It has been reached.

That is, the invention of claim 1 provides at least a peak top molecular weight (M) in a chromatogram measured by gel permeation chromatography of a coloring agent, a charge controlling agent and a tetrahydrofuran-soluble component.
p) is 3000 or more and the number average molecular weight (Mn) is 2700
An electrostatic charge developing toner using the crosslinked polyester resin (A) and / or the crosslinked polyether polyol resin (B) described above. The peak top molecular weight (Mp) is 7000 or more in the chromatogram measured by the aspiration chromatography, and the number average molecular weight (Mp)
n) is at least 4500, and a ratio of the weight average molecular weight to Mw, Mw / Mn, is 2 ≦ Mw / Mn ≦ 10, and the linear polyester resin (C) is mixed with the resin (A) and / or (B). The electrostatic charge developing toner according to claim 1, wherein:

The invention of claim 3 is characterized in that the inorganic fine particles (a) having a BET specific surface area of 100 m ² / g or more are mixed with 60 m ² / g.
The toner for electrostatic charge development according to claim 1, wherein a mixture of the following inorganic fine particles (b) is carried on the surface. The invention according to claim 4, wherein the average particle diameter is 0 by a wet method. 2. The electrostatic charge developing toner according to claim 1, wherein a charge control agent pulverized to 0.7 μm or more is fixed to the surface of the toner particles. 3. The toner according to claim 1, wherein the developing sleeve is made of a non-magnetic one-component developing device made of metal. 2. The electrostatic charge developing toner according to claim 1, wherein the toner is used in a non-magnetic one-component developing device comprising: The glass transition point of the toner is 50 to 70 ° C. and the flow softening point is 10%.
The toner according to claim 1, wherein the temperature is 5 to 135C.

The crosslinked polyester resin or polyether polyol resin used in the present invention needs to have a peak top molecular weight (Mp) of 3,000 or more, preferably 3200 or more, more preferably 35 or more.
00 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) needs to be 2700 or more, preferably 3000 or more, more preferably 3500 or more. When Mn is less than 2700, 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. It is not preferable because it occurs.

Usually, in the crosslinked polyester resin (A), the crosslinked polyether polyol resin (B) of the present invention is used.
When it has a molecular weight distribution equivalent to that of the above, toner fusion to the developing device member may occur, but 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, high toughness is also advantageous in terms of fixing properties, such as a wide non-offset temperature range, a small amount of oil applied to the fixing roller, and especially when a solid image is bent. It has advantages such as little toner peeling.

As described above, although the crosslinked polyether polyol resin exhibits good characteristics in comparison with the crosslinked polyester resin in achieving both durability and fixability,
In comparison with a crosslinked polyester resin, the hydroxyl value may be high due to the resin composition. When the hydroxyl value is high, the negative chargeability is poor, and fog and toner scattering may occur.
On the other hand, the crosslinked polyester resin can keep the hydroxyl value low. When the above-mentioned problems such as fogging and toner scattering occur when the crosslinked polyether polyol resin is used alone, the compatibility between the fixing property and the durability is slightly inferior. By using a polyester resin alone or by mixing it with a crosslinked polyether polyol resin, good chargeability can be obtained, and problems such as fogging and toner scattering can be avoided.

The linear polyester resin (C) according to claim 2 used in the present invention has a peak top molecular weight (Mp) of 700.
0 or more is required, more preferably 7500 or more, and still more preferably 8000 or more. Mp is 700
If it is less than 0, low molecules in the oligomer region increase, 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 fogging and toner scattering. Absent.

Further, the number average molecular weight (Mn) of the linear polyester resin (C) needs to be 4500 or more, preferably 5000 or more, more 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 (C) used in the present invention has a weight average molecular weight (Mw) and a number average molecular weight (Mw).
n), the ratio Mw / Mn needs to be 2 ≦ Mw / Mn ≦ 10, preferably 2 ≦ Mw / Mn ≦ 8,
More preferably, 2 ≦ Mw / Mn ≦ 5. Mw / Mn
Is less than 2, the brittleness of the linear polyester resin (C) is increased, and the linear polyester resin (C) 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, Mw / Mn
When the ratio is more than 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. By reducing the degree of crosslinking of the crosslinked polyester resin and / or the crosslinked polyether polyol resin used in the present invention, it is possible to impart an appropriate gloss to the image. Furthermore, by using the linear polyester resin (C) in combination with the cross-linked polyester resin (A) and / or the cross-linked polyether polyol resin (B), both low-temperature fixability and durability can be achieved. Thus, the glossiness can be arbitrarily adjusted.

The toner for electrostatic charge development of the present invention employs a method in which a charge control agent is internally added to toner particles by a conventional kneading and pulverizing method, but is pulverized to a mean particle diameter of 0.7 μm or less by a wet method. It is desirable that the charge control agent is fixed to the surface of the toner particles. The average particle size of a commercially available charge control agent that is commonly used is on the order of microns, and at least about 1 μm. When a relatively large charge control agent is attached to the toner particle surface using a mechanical distorting force by using a hybridizer (manufactured by Nara Machinery Co., Ltd.), most of the charge control agent particles When embedded and fixed on the toner particle surface, the charge control agent particles having an excessively large particle diameter cannot be fixed on the toner particle surface, and contaminate electrophotographic members such as a developing device and a photoreceptor in a copying process. This causes problems such as fog and toner scattering. In the present invention, as a result of intensive studies to solve such problems, the charge control agent was finely pulverized to 0.7 μm or less in a submicron region in a wet-dispersed solvent in a media type fine pulverizer. It has been found that good image characteristics can be obtained by fixing the charge control agent on the toner particle surface. 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 while being wet in a solvent and dried, so that the charge control agent can be easily dispersed and adhered uniformly to the surface of the toner particles. . In preparing the toner for electrostatic charge development of the present invention, the toner is prepared by a wet method as described above.
The charge control agent pulverized to 7 μm or less may be dried once and then mixed with the toner particles. The term "particle diameter" used herein refers to the average value of the major axis and minor axis of each particle in the photograph of the particles of the pulverized charge control agent obtained by photographing with an electron microscope at a magnification of 1000 times. It is the average value of the particle diameters of 200 individual particles defined and arbitrarily selected. In the present invention, after the charge control agent is dispersed and adhered to the toner particle surface as described above, the charge control agent can be buried and fixed on the toner particle surface using the above-described hybridizer or Henschel mixer. .

The crosslinked polyol polyether resin (B) specified in the present invention generally has poor chargeability. However, in addition to including a normal charge control agent in the toner particles, the crosslinked polyol polyether resin (B) further has a particle size of 0.7 μm. By embedding and fixing the charge control agent finely pulverized to the surface of the toner particles as described below, the chargeability is improved, and a very good electrophotographic image without memory or fog can be obtained.

The toner for developing an electrostatic charge of the present invention comprises inorganic fine particles (a) having a BET specific surface area of 100 m ² / g or more,
It is preferable to use a mixture of inorganic fine particles (b) of m ² / g or less in combination with toner particles. The inorganic fine particles (a) having a particle size of 100 m ² / g or more are used mainly for imparting fluidity to the toner. 60 m ² / g or less inorganic fine particles (b)
Mainly has a high polishing effect and a high effect of preventing fusion of toner particles to a developing roller or a blade. By using both, there is no decrease in fluidity even in continuous copying,
A stable image without a decrease in image density can be obtained. One of the inorganic fine particles (a) has a BET specific surface area of 100
When it is less than m ² / g, sufficient fluidity cannot be obtained, and the image density becomes insufficient. On the other hand, if the BET specific surface area of the other inorganic fine particles (b) is larger than 60 m ² / g, a sufficient polishing effect cannot be obtained, and the toner may be fused to the developing roller or blade. 60m ² / g
The following inorganic fine particles (b) are desirably added in an amount of 2.5 parts by weight or less based on 100 parts by weight of the toner particles. If more than 2.5 parts by weight is added, fluidity may be impaired and a sufficient image density may not be obtained. On the other hand, the amount of the inorganic fine particles (a) of 100 m ² / g or more is desirably 3 parts by weight or less. If more than 3 parts by weight is added, the coating of the inorganic fine particles on the toner particles becomes excessive, and the fixability may be impaired.

Examples of the inorganic fine particles (a) and (b) include silica, alumina, titanium oxide, magnetite, zinc oxide, silicon carbide, zirconia and the like, and compounds with organic substances such as magnesium stearate and zinc stearate. It can be suitably used. Also, inorganic fine particles (a)
Is not limited to the compounds exemplified above.

In the present invention, when the developing sleeve is made of metal, it is preferable to use a relatively large amount of the mixture of the inorganic fine particles since the fusion of the toner to the developing sleeve and the blade can be prevented well. . That is, the inorganic fine particles (b) having a particle size of 60 m ² / g or less are added in an amount of 2.
The inorganic fine particles (a) mixed in a large amount in the range of 5 parts by weight or less and 100 m ² / g or more have excellent durability when mixed in a large amount in the range of 3 parts by weight or less. On the other hand, when the developing sleeve is a substance having elasticity other than metal, such as rubber, in the above-described inorganic fine particle addition range, it is desirable in terms of durability that both addition amounts be as small as possible, The addition amount can be appropriately determined in consideration of the fluidity.

Hereinafter, the materials used in the present invention will be described. The crosslinked polyester resin (A) or linear polyester resin (C) used in the toner for electrostatic charge development of the present invention is obtained by polycondensation of a divalent carboxylic acid and a diol. Examples of the divalent carboxylic acid here include, for example, malonic acid, succinic acid, azelaic acid, sebacic acid, aliphatic dibasic acids such as hexahydrophthalic anhydride, and phthalic anhydride, phthalic acid, terephthalic acid, isophthalic acid, and the like. And their lower alkyl esters and halides.

The diol mentioned here includes, for example, ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,2-butanediol, 1,3-butanediol, 1,4-butane Diol, 1,6-hexanediol, neopentyl glycol, diethylene glycol, dipropylene glycol, cyclohexane dimethanol, hydrogenated bisphenol A, bisphenol A ethylene oxide adduct, bisphenol A propylene oxide adduct, polypropylene glycol, polytetramethylene glycol, etc. Can be exemplified.

In the case of a crosslinked polyester resin, a derivative of an unsaturated dibasic acid is usually used and can be produced by a crosslinking reaction with a crosslinking initiator.

The electrostatic charge developing toner of the present invention may contain the following binder resins in addition to the specific polyester resins (A) and (C) and the polyether polyol resin (B). 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-acrylate copolymer (styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer, styrene-acryl Octyl acid copolymer and styrene-phenyl acrylate copolymer), styrene
Methacrylate copolymers (styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-octyl methacrylate copolymer and styrene-phenyl methacrylate copolymer), styrene-
Styrene resins (homopolymers or copolymers containing styrene or styrene substituents) such as α-chloromethyl acrylate copolymer and styrene-acrylonitrile-acrylate copolymer, vinyl chloride resin, rosin-modified maleic acid Resins, phenol resins, epoxy resins, low molecular weight polyethylene, ionomer resins, polyurethane resins, silicone resins, ketone resins, ethylene-ethyl acrylate copolymers, xylene resins, polyvinyl butyral resins, etc. can be applied to the present invention. When these resins are contained, the content is about 60 to 100 parts by weight based on a total of 100 parts by weight of the specific polyester resin and / or the specific polyether polyol resin.

Colorants include carbon black, aniline blue, calco oil blue, chrome yellow, ultramarine blue, Dupont oil red, quinoline yellow, methylene blue chloride, phthalocyanine blue, malachite green oxalate, 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 25 to 75 nm, particularly 30 to 55 nm,
The specific surface area is preferably 110 m ² / g. 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.
It is preferably 2 to 20 parts by weight based on parts by weight.

The electrostatic charge developing toner of the present invention may contain other additives such as a charge controlling agent and a release agent. Examples of the charge control agent include metal-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 their manganese, cobalt,
Metal salts such as iron, zinc, aluminum, and lead, and alkylsalicylate 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 binder resin. 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 the developing characteristics to obtain a high quality image.

The crosslinked polyester resins (A) and (C) and the polyether polyol resin (B) of tetrahydrofuran (hereinafter, referred to as “B”) blended in the toner for developing an electrostatic charge of the present invention.
The molecular weight of the soluble component is measured by gel permeation chromatography (hereinafter abbreviated as GPC), and is determined by the peak top of the crosslinked polyester resin (A) and polyether polyol resin (B). The molecular weight (MP) is 3000 or more, the number average molecular weight (Mn) is 2700, the polyester resin (C) has a peak top molecular weight (MP) of 7000 or more, the number average molecular weight (Mn) is 4500 or more, and the weight average molecular weight (Mw) is 4500 or more and the weight average molecular weight (M
w), and Mw / Mn is 2 ≦ Mw / Mn ≦ 10. Further, as a toner for electrostatic charge development,
In the same GPC measurement, it is desirable that the compound has no peak at a molecular weight of 1,000 or less. The peaks in the chromatogram referred to here are clearly peaks in the chart curve, except for those whose shoulder-like curves cannot be drawn in the up-down direction, and clearly peaks in the chart curve (repeated curves can be drawn in the up-down direction) It refers to a curve.

Further, in the toner for developing an electrostatic charge of the present invention, in order to obtain low-temperature fixing characteristics, the glass transition point Tg in the thermal characteristics is 50 to 70 ° C., and the flow softening point is 105 to 15.0.
35 ° C. is preferable, and the glass transition point Tg is 50 to 6
More preferably, the flow softening point is 5 ° C and 110 ° C to 130 ° C. In this case, the glass transition point Tg of the toner is 5
If the temperature is lower than 0 ° C. or the flow softening point is lower than 105 ° C., offset tends to occur mainly on the high temperature side, and the usable fixing temperature width tends to be narrow. Also, simply lowering the molecular weight is not preferred because toner cracks are likely to occur in the developing tank and durability tends to deteriorate.
Conversely, when the glass transition point Tg exceeds 70 ° C. or when the flow softening point exceeds 135 ° C., the low-temperature fixability tends to deteriorate, which is not preferable. The glass transition point Tg in the present invention refers to the temperature of the shoulder portion of the endothermic peak in DSC (differential scanning calorimeter).

On the other hand, the flow softening point refers to the temperature at the middle point from the drop start temperature to the drop end temperature of the plunger under the following measurement conditions using an elevated flow tester CF-500 manufactured by Shimadzu Corporation. Shall be. The glass transition point of the toner is less than 70 ° C. and the flow softening point is 135 ° C.
It is preferred that the toner for electrostatic development is less than.

Measurement conditions Plunger; 1 cm ² Die diameter; 1 mm Die length; 1 mm Load; 20 kgf Preheating temperature; 50 to 80 ° C Preheating time; 300 sec Temperature rising rate: 6 ° C / min

The electrostatic charge developing toner of the present invention develops an electrostatic image by using a developing device comprising at least a developing roller or a developing film and a layer regulating member.
Then, it is suitably used for a non-magnetic one-component developing method for transferring to a transfer material. Examples of such a non-magnetic one-component developing method include, for example, a contact-type developing method described in JP-A-10-221949 and JP-A-9-16028.
A non-contact type developing method described in Japanese Patent Application Laid-Open No. 7-107 is mentioned.

[0035]

The present invention will be described in more detail with reference to the following Examples and Comparative Examples. In the examples below, “parts” means “parts by weight”.

Example 1 The following materials were weighed.・ Polyether polyol resin ... (trade name, manufactured by Mitsui Chemicals; TPO-067 Mp ... 3300, Mn ... 3050) 30 parts ・ Linear polyester resin ... (trade name, manufactured by Mitsui Chemicals; XPE-2285 Mp ... 11000, Mn ...) 4800) 70 parts ・ Carbon black (trade name; # 40, manufactured by Mitsubishi Chemical Corporation) 6 parts ・ Charge control agent: (trade name, S44, manufactured by Orient Chemical Co.) 1 part ・ Polyethylene wax… (trade name, manufactured by Clariant; PE) -190) 2 copies

The above 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, NAX50 (B
0.5 parts of ET specific surface area: 50 m ^{2 /} g) and H-2000 (BET specific surface area: 1) manufactured by Clariant
(30 m ^{2 /} g) was mixed with a Henschel mixer to obtain a toner for electrostatic charge development of the present invention having an average particle diameter of 9.3 μm.

Example 2 A cross-linked polyester resin (trade name, manufactured by Mitsui Chemicals, Inc .; XPE-1954 Mp.5400, Mn..3500) instead of the polyether polyol resin of Example 1 was replaced with 30 parts. Thus, toner particles were obtained. Other than the above, external addition was performed in the same manner as in Example 1 to obtain a toner for electrostatic charge development according to the present invention having an average particle diameter of 9.5 μm.

Example 3 In place of 30 parts of the polyether polyol resin of Example 1, the following resin was used. Polyether polyol resin ... (trade name, manufactured by Mitsui Chemicals; TPO-067 Mp ... 3300, Mn ... 3050) 15 parts Crosslinked polyester resin ... (trade name, manufactured by Mitsui Chemicals; XPE-1954) Mp ... 5400, Mn ... 3500 15 parts Except for this, the average particle diameter is 9.1 in the same manner as in Example 1.
A .mu.m toner for electrostatic development according to the invention was obtained.

Example 4 In Example 1, the polyether polyol resin and
Without using a linear polyester resin, only a cross-linked polyester resin (trade name: XPE1954, manufactured by Mitsui Chemicals, Inc.)
A toner for electrostatic charge development according to the present invention having an average particle diameter of 9.0 μm was obtained in the same manner as in Example 1 except that 00 parts were used.

Example 5 In Example 1, except that a linear polyester resin was not used and only 100 parts of a polyether polyol resin was used.
Colored particles were obtained in the same manner as in Example 1. To 100 parts of the obtained colored particles, 0.5 part of a charge controlling agent (trade name: S-44, manufactured by Orient Chemical Co., Ltd.) previously ground to a mean particle diameter of 0.5 μm with a media pulverizer, a Henschel mixer , And the charge control agent was fixed to the surface of the toner particles using a hybridizer (manufactured by Nara Machinery Co., Ltd.), and then externally added in the same manner as in Example 1 to obtain an average particle size of 9.0 μm. Of the present invention was obtained.

Comparative Example 1 The resin of Example 1 was replaced with the following resin.
All were in the same manner as in Example 1 and had an average particle size of 8.8 μm.
Of Comparative Example 1 was obtained. 100 parts of linear polyester resin ... (trade name X, manufactured by Mitsui Chemicals, Inc .; PE-1998 Mp ... 6300, Mn ... 3400, Mw / Mn = 2.0)

Comparative Example 2 Except that all of the resins of Example 1 were changed to the following resins,
In the same manner as in Example 1, a comparative electrostatic charge developing toner having an average particle diameter of 8.8 μm was obtained. 100 parts of linear polyester resin (trade name; manufactured by Mitsui Chemicals, Inc .; XPE-2176) Mp ... 6300, Mn ... 3200, Mw / Mn = 2.0

Comparative Example 3 The resin of Example 1 was replaced with the following resin.
All were in the same manner as in Example 1 and had an average particle size of 8.8 μm.
Of Comparative Example 1 was obtained. 100 parts of linear polyester resin (trade name, manufactured by Mitsui Chemicals, Inc .; XPE-2372 Mp ... 6300, Mn ... 3700, Mw / Mn = 2.0)

The following characteristics were evaluated with respect to the electrostatic charge developing toners of Examples and Comparative Examples obtained by the above operations. (1) Durability Table 1 shows the occurrence of fusing in a developing device built into a copying machine of a non-magnetic one-component developing device having an aluminum developing sleeve (trade name of FP-C1A manufactured by Matsushita Electric Industrial Co., Ltd.). Table 2 shows the fusing occurrence time in a non-magnetic one-component developing apparatus having a urethane rubber developing sleeve (trade name, manufactured by NEC Corporation; a developing device for Multiwriter 2050).

In each of the tests, the developing device has a stirring member made of sponge rubber which comes into contact with the developing sleeve. 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. The developing device was removed from the printer main body, and the toner was continuously stirred using a dedicated driving device. The amount of toner charged into the developing device was 100 g. The fusing time is from the start of stirring to the development sleeve that constitutes the developer
It means the time until the toner is fused to either the layer regulating member or the stirring member. The test was performed for up to 4 hours, and even after the lapse of 4 hours, if there was no fusion of the toner to the above-mentioned member, it was described as 4 hours or more.

[0047]

[Table 1]

[0048]

[Table 2]

From the above results, it was confirmed that the electrostatic charge developing toner of the present invention had good durability.

(2) Fixing property Next, the results of the fixing test are shown in Table 3. Fixing property is 130 ~
The reflection density reduction rate (%) before and after rubbing or bending of a 2 cm × 2 cm square solid portion fixed at 220 ° C. by changing the fixing temperature at 10 ° C. intervals was measured, and this value was taken as the fixing rate (%). . Fixing device (product name 830, manufactured by Sharp Corporation)
The fixing roller used for the first roller is an aluminum cylinder coated with a fluorine resin (trade name: Teflon) manufactured by DuPont, and has a structure in which a heater lamp is inserted inside the cylinder. The lower roller is made of silicone rubber. The fixing speed was 200 mm / sec. The surface temperature of the upper roller can be continuously variable and adjusted between 130 and 220 ° C. In the bending test, the fixing device was driven at room temperature at 100 mm / sec, and the solid was bent with the center of the solid inward. Then, the fixing test piece was passed through, and the fixing test piece was inserted in the direction perpendicular to the obtained fold. Then, the portion where the fold of the fixing sample passed through the fixing roller crossed in the solid portion was rubbed in the same manner as in the rubbing test. In the bending test, the fixing temperature at which the fixing rate was 60% was used as the evaluation value.
The reflection density before and after the bending test was measured using Macbeth RD-914. Table 3 shows the results of the fixing test.

[0051]

[Table 3]

As is apparent from Table 3, the toner for electrostatic charge development of the present invention has a lower fixing temperature for securing a fixing rate of 60% as compared with the toner of the comparative example, and therefore has good fixability. Has been demonstrated.

(3) Changes in Image Characteristics Table 4 shows the results of tests on changes in image characteristics during continuous use. As for the developing device using the aluminum developing sleeve, a copying machine of ipsio 2100 manufactured by Ricoh Company was used. With respect to the developing device using the urethane rubber developing sleeve, a printer of NEC's 2150 multi-writer was used. Image density was measured by Macbeth RD-
914. 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. The results are as shown in Table 4.

[0054]

[Table 4]

From the results shown in Table 4, it was proved that the electrostatic charge developing toner of the present invention had almost no change in image density and had good image characteristics with little fog.

[0056]

According to the present invention, it takes a long time to generate fusion in a metal sleeve or a non-metal sleeve in continuous use, the durability time is drastically increased, and the fixation in a bending test is performed. The temperature was lower than the conventional one, and a toner with less fog could be provided.

Claims (7)

[Claims] At least a peak top molecular weight (Mp) of 3000 or more and a number average molecular weight (Mn) of 2700 in a chromatogram measured by gel permeation chromatography of at least a coloring agent, a charge control agent and a tetrahydrofuran-soluble component. An electrostatic charge developing toner using the above-mentioned crosslinked polyester resin (A) and / or crosslinked polyether polyol resin (B). 2. A chromatogram measured by gel permeation chromatography of a tetrahydrofuran-soluble component, which has a peak top molecular weight (Mp) of 7000 or more, a number average molecular weight (Mn) of 4500 or more, and a weight average molecular weight Mw. Where Mw / Mn is 2 ≦ Mw / Mn ≦
The toner according to claim 1, wherein the linear polyester resin (C) is mixed with the resin (A) and / or the resin (B). 3. The method according to claim 1, wherein a mixture of inorganic fine particles (a) having a BET specific surface area of 100 m ² / g or more and inorganic fine particles (b) of 60 m ² / g or less is supported on the surface. 4. The toner for electrostatic charge development according to item 1. 4. The electrostatic charge developing toner according to claim 1, wherein a charge control agent pulverized to an average particle diameter of 0.7 μm or less by a wet method is fixed to the surface of the toner particles. 5. The electrostatic charge developing toner according to claim 1, wherein the toner is used in a non-magnetic one-component developing device in which a developing sleeve is made of metal. 6. The electrostatic charge developing toner according to claim 1, wherein the developing sleeve is used for a non-magnetic one-component developing device made of a material having elasticity other than metal. 7. The toner according to claim 1, wherein the toner has a glass transition point of 50 to 70 ° C. and a flow softening point of 105 to 135 ° C.