JPH05134453A - Developer for developing eolectrostatic charge image - Google Patents

Abstract

PURPOSE:To provide a developer for developing an electrostatic charge image ensuring a proper amt. of charges by triboelectric charge in an environment at low temp. and humidity even when applied to a highspeed machine and having excellent fixability and durability. CONSTITUTION:This developer for developing an electrostatic charge image contains a toner and a carrier and the binding resin of the toner is polyester obtd. by condensation-polymerizing a monomer compsn. contg. arom. dicarboxylic acid (A), a tri- or higher valent monomer (B), alkyl- or alkenylsuccinic acid, acid anhydride or lower monoalkyl ester thereof (C) and aliphatic diol (D).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrostatic charge image developing developer used in electrophotography, electrostatic printing and the like. More specifically, it relates to a developer for developing an electrostatic charge image containing a toner and a carrier.

[0002]

2. Description of the Related Art Conventionally, a method such as a cascade image method or a powder cloud method is known as a method for developing a developer for developing an electrostatic charge image in an electrophotographic method, but generally toner is efficiently conveyed to a developing section. In order to achieve this, a method of mixing with carrier particles such as iron powder and ferrite powder to form a magnetic brush and rubbing and developing an electrostatic charge image is widely known.

As still another developing method, a developer container for storing toner and magnetic particles for toner application, a toner carrier for transporting toner to a latent image carrier, and an upstream side of the toner outlet of the developer container. A magnet forming a magnetic brush of magnetic particles for toner application, which is in contact with the toner carrier, is arranged to form a thin layer of toner on the toner carrier.
There is a method of developing an electrostatic image by setting a gap between the toner carrier and the electrostatic holder larger than the toner layer thickness.

According to these methods, it is necessary to substantially keep the toner in a uniformly mixed state with a carrier or in a uniformly thin layer coated state on a carrier in the developing section, and yet to achieve that state. The force is mainly dominated by electrostatic attraction and physical adhesion. That is, it is necessary to precisely control the electrostatic charge amount and the triboelectric charging ability of the toner.

However, it is quite difficult to uniformly control the charge amount of the toner, and to stabilize the charge amount even after repeated copying over a long period of time or under a special environment of high temperature and high humidity and low temperature and low humidity. It is accompanied by.

Therefore, from JP-A-58-14144, JP-A-60-176049, JP-A-62-127748 and JP-A-62-127749, a toner and a resin-coated carrier containing a cross-linked polyester as a binder resin are disclosed. A developing agent is disclosed.

However, 1) When the developer is mechanically agitated in the developing device during durability in a low temperature and low humidity environment, the toner particles and the carrier coating layer are destroyed and the triboelectric chargeability of the toner becomes unstable.

2) When the durability is achieved in the intermittent mode, the time during which the developer is agitated in the developing device becomes long. As a result, the toner particles and the carrier coating layer are destroyed, and the triboelectric chargeability of the toner becomes unstable. There are problems such as.

Therefore, Japanese Patent Laid-Open No. 1-204062 is disclosed. Certainly, by using a specific polyester as the binder resin for the toner, it is possible to prevent the toner particles and carrier coating layer from being destroyed during durability in low temperature and low humidity environments and during durability in the intermittent mode, and to improve the triboelectric chargeability of the toner. It is possible to obtain a developer that is stabilized and has excellent durability, fixability, offset resistance, and blocking resistance.

However, when it is attempted to apply the technique disclosed in Japanese Patent Laid-Open No. 1-204062 to future high-speed copying machines in order to increase the speed of copying machines in recent years, triboelectrification and developing properties under low temperature and low humidity environment conditions are considered. It is difficult to say that the transferability, cleaning property, and fixing property are sufficient, and it is difficult to stably form a good image having high image density and sufficient fixing property without causing fog and image disturbance. ..

Further, in recent years, in order to obtain a high resolution, the toner particle size is being reduced, but it is disclosed in Japanese Patent Laid-Open No. 1-204062
It is difficult to improve the pulverizability when the toner has a smaller particle diameter with the technique disclosed in the publication. In order to improve pulverizability during toner production, the proportion of aliphatic diol in the monomer composition must be increased. However, when the proportion of the aliphatic diol in the monomer composition is increased, the glass transition temperature and softening point of the synthesized polyester are lowered. For this reason, the blocking resistance and offset characteristics of the toner deteriorate, and when the toner is durable under high temperature and high humidity, there arises a problem that the toner rubbed near the cleaning blade is fused to the drum.

[0012]

SUMMARY OF THE INVENTION An object of the present invention is to provide a developer for developing an electrostatic charge image, which has stable and uniform chargeability when applied to a high speed machine.

Still another object is to provide a developer for developing an electrostatic charge image, which maintains the initial characteristics even when the toner is continuously used for a long period of time.

Still another object is high temperature, low temperature and high humidity,
An object of the present invention is to provide a developer for developing an electrostatic charge image that is not easily affected by environmental changes such as low humidity.

Still another object is to provide a developer for developing an electrostatic charge image capable of obtaining a high quality image.

Still another object of the present invention is to provide a developer for developing an electrostatic charge image, which is excellent in storage stability and retains initial characteristics even after storage for a long time.

Still another object is to provide a developer for developing an electrostatic charge image, which has excellent pulverizability when producing a toner.

[0018]

A feature of the present invention is that in an electrostatic charge image developing developer containing a toner and a carrier, (A) an aromatic dicarboxylic acid (A) is used as a binder resin for the toner. B) Trivalent or higher polyvalent monomer (C) Alkyl or alkenyl succinic acid or its acid anhydride or its lower monoalkyl ester (D) Polyester obtained by condensation polymerization of a monomer composition having an aliphatic diol It is a developer for electrostatic image development used.

The inventors of the present invention continued to find out that the above object can be achieved by using a specific polyester resin as a binder resin.

The polyester is a polyester obtained by polycondensation of the monomer composition consisting of the above (A) to (D). Since an aliphatic diol is used, a flexible molecular chain is imparted to the polyester structure to form an intermolecular structure. The cohesive force can be reduced, and the energy received during friction and rubbing can be absorbed and relaxed by molecular motion.

Therefore, the mechanical stress applied to the carrier resin coating layer can be alleviated by stirring the developer, and the toner particles and the carrier coating layer can be prevented from being destroyed.

Therefore, it is possible to obtain an effect that the electrostatic property of the developer for developing an electrostatic image is excellent in environmental stability, prevent an excessive increase in the charge amount under low temperature and low humidity, and prevent fog and image disturbance. An image with high image density can be obtained without any occurrence.

Further, since the energy received when the toner is rubbed or rubbed is absorbed and relaxed by the molecular motion, the generation of scratches on the photoconductor is suppressed, and the cleaning failure and the image disturbance are not caused, and the durability of the photoconductor is improved. The property is improved.

Further, since the anchoring effect of the toner on the paper at the time of fixing becomes excellent, the fixability in a low temperature and low humidity environment can be improved.

Here, it is preferable to use two or more kinds of aliphatic diols in combination in the monomer composition. When only one type of aliphatic diol is contained in the monomer composition, it is often difficult to control the reaction during polyester synthesis, and the softening point and glass transition point of the synthesized polyester are often lowered. In many cases, the blocking resistance of the toner is lowered, and drum fusion occurs during durability under high temperature and high humidity.

When the proportion of the aliphatic diol in the monomer composition exceeds 60 mol%, it becomes difficult to control the reaction during polyester synthesis, and it is often difficult to obtain a polyester having stable performance. Further, the glass transition temperature and the softening point of the obtained polyester are lowered, the blocking resistance of the toner is lowered, and the toner melt-adhesion may occur during durability under high temperature and high humidity.

If the proportion of the aliphatic diol in the monomer composition is less than 45 mol%, the above effect cannot be obtained.

Further, since the aromatic dicarboxylic acid is present in the monomer composition, a rigid molecular chain is imparted to the obtained polyester. Therefore, the durability of the developer for developing an electrostatic image can be improved.

The ratio of the aromatic dicarboxylic acid in the monomer composition is preferably 50 mol% or less. If the proportion of the aromatic dicarboxylic acid in the monomer composition exceeds 50 mol%, the pulverizability during toner production deteriorates.

Further, since the polyvalent monomer having a valence of 3 or more is present in the monomer composition, the obtained polyester can have a three-dimensional network structure, and can impart appropriate elasticity to the polyester. You can Therefore, the repulsive force of the toner against the fixing roller during fixing is increased, so that a developer for electrostatic image development having excellent offset resistance can be obtained.

The proportion of the trivalent or higher polyvalent monomer in the monomer composition is preferably 40 mol% or less.

If the abundance ratio of the polyvalent monomer having a valence of 3 or more is excessive, it becomes difficult to control the reaction during the polyester synthesis, and it becomes difficult to obtain a polyester having stable performance. Also, the pulverizability during toner production deteriorates.

If the abundance ratio of the trivalent or higher polyvalent monomer is too small, the offset resistance is deteriorated.

Further, since alkyl or alkenyl succinic acid or its acid anhydride or its lower monoalkyl ester is present in the monomer composition, a flexible molecular chain is imparted to the polyester structure and intermolecular cohesive force is imparted. The energy received during friction or rubbing can be absorbed and relaxed by molecular motion. The use of alkenyl succinic acid is more preferable than the case of using alkyl succinic acid, because it is more preferable to use alkenyl succinic acid. This effect is greater than the effect obtained by the above aliphatic diol. Therefore, the sliding property of the toner can be significantly improved against the friction and rubbing that the toner receives. For this reason, the slipperiness of the toner with respect to the fixing roller is improved, and the toner on the unfixed image that has passed through the fixing roller is preferentially attached to the paper instead of the fixing roller, without lowering the offset generation temperature. The effect of lowering the minimum fixing temperature can be obtained.

However, if the proportion in the monomer composition is less than 10 mol%, the effect of lowering the minimum fixing temperature is small, and conversely if the proportion in the monomer composition exceeds 25 mol%. The glass transition temperature is lowered and the blocking resistance of the toner is lowered.

In the present invention, by using the polyester obtained by polycondensation of the above (A) to (D), the following functions (a), (b) and (c) can be obtained in addition to the above functions. You can

(A) The polyester described above can reduce the resistance to mechanical impact, so that the pulverizability at the time of toner production can be improved.

(B) The above polyester can lower the softening point as compared with the conventional one without lowering the glass transition temperature. Therefore, the kneading temperature set during toner production can be lowered, and the toner can be produced at a lower cost.

(C) The charge amount on the sleeve of the toner using the above polyester is very stable as compared with the conventional one even if the toner is durable under various environmental conditions. Therefore, the transfer efficiency at the time of transfer is improved, and an image having excellent fine line reproducibility in terms of image quality can be obtained.

The present inventors have the actions (a), (b),
The reason for (c) is presumed as follows.

In the above (A) to (D) monomer compositions,
The chemical structure capable of lowering the glass transition temperature in the synthesized polyester due to the presence of (C) alkyl or alkenyl succinic acid or its acid anhydride or its lower monoalkyl ester and (D) aliphatic diol. (So-called soft segment) can be present. Here, since the component (C) has an alkyl group or an alkenyl group in the side chain, by using the component (C) together as a monomer composition, an increase of an amorphous part in the structure of the synthesized polyester is caused. Conceivable. Therefore, it is considered that the component (D) mainly forms a soft segment in the crystalline portion and the component (C) mainly forms a soft segment in the amorphous portion. Here, the component (C),
By using (D) together, the presence of the soft segment in the polyester structure can be present in the crystalline portion and the amorphous portion in a well-balanced manner, and it becomes possible to control the balance of the molecular mobility, and the above action (a) ,
We speculate that we can obtain (b) and (c).

Here, the acid value (AV) is measured by weighing 2 to 10 g of the sample in an Erlenmeyer flask of 200 to 300 ml and mixing the mixed solvent of methanol: toluene = 30: 70 to about 5%.
Add 0 ml to dissolve the resin. If the solubility seems to be poor, a small amount of acetone may be added. Using a mixed indicator of 0.1% bromthymol blue and phenol red,
Titration is performed with a previously standardized N / 10 potash-alcohol solution, and the acid value is calculated from the consumption amount of the alcohol potash according to the following calculation formula (1).

Acid value = KOH (ml) × N × 56.1 / Sample weight (1) (where N is a factor of N / 10 KOH) Further, the hydroxyl value was measured by measuring the sample with an excessive acetylating agent,
For example, acetylation is performed by heating with acetic anhydride, the saponification number of the acetylated product produced is measured, and then calculated according to the following calculation formula (2).

(Where A is the sapon number after acetylation and B is the sapon number before acetylation) The softening point of the polyester of the binder resin of the present invention is preferably 80 to 170 ° C. When the softening point is lower than 80 ° C., the blocking resistance and offset resistance of the toner deteriorate. Further, when the softening point exceeds 170 ° C., the fixing property of the toner deteriorates.

In measuring the softening point, the flow tester CFT is used.
-500 type (made by Shimadzu) is used.

Under normal temperature and normal humidity (temperature of about 20 to 30 ° C., humidity of 3
A flow tester measurement is performed at 0 to 70% RH) to obtain a temperature-apparent viscosity curve. When the height of the S-shaped curve in the temperature-apparent viscosity curve of the obtained flow tester was h, the temperature at h / 2 was taken as the softening point.

The glass transition temperature Tg of the polyester as the binder resin of the present invention is preferably 50 to 70 ° C. When the glass transition temperature is lower than 50 ° C., the blocking resistance and offset resistance of the toner deteriorate. Glass transition temperature T
When g exceeds 70 ° C., the fixability deteriorates.

Here, in the present invention, the glass transition temperature T
g is measured by a differential thermal analysis measuring device (DSC measuring device),
It measures using DSC-7 (made by Perkin-Elmer company).

Specific examples of each of the components (A) to (D) are as follows.

Examples of the aromatic dicarboxylic acid as the component (A) include terephthalic acid, isophthalic acid, orthophthalic acid, cyclohexanedicarboxylic acid, 3,5-toluenedicarboxylic acid, 2,5-toluenedicarboxylic acid and the like. Examples thereof include acid anhydrides and lower monoalkyl esters.

Examples of the trivalent or higher polyvalent monomer as the component (B) include trivalent or higher polyvalent carboxylic acids or trivalent or higher polyhydric alcohols.

The trivalent or higher polycarboxylic acid is 1,
2,4-benzenetricarboxylic acid, 1,3,5-benzenetricarboxylic acid, 1,2,4-cyclohexanetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid,
2,5,7-naphthalene tricarboxylic acid, 1,2,4-
Butanetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, tetra (methylenecarboxy) methane, 1,3
Examples thereof include polycarboxylic acids such as -dicarboxyl-2-methyl-2-methylenecarboxypropane, 1,2,7,8-octanetetracarboxylic acid, their acid anhydrides and lower alkyl esters.

Examples of the trihydric or higher polyhydric alcohol include sorbitol, 1,2,3,6-hexanetetrol, 1,
4-sorbitan, sucrose, 1,2,4-butanetriol, 1,2,5-pentatriol, glycerol,
Pentaerythritol, dipentaerythritol, tripentaerythritol, 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, trimethylolpropane, 1,3,3.
Examples thereof include 5-trihydroxymethylbenzene.

Examples of the alkyl or alkenyl succinic acid as the component (C) include n-butyl succinic acid, n-butenyl succinic acid, isobutyl succinic acid, isobutenyl succinic acid,
n-octyl succinic acid, n-octenyl succinic acid, n-
Dodecyl succinic acid, n-dodecenyl succinic acid, isododecyl succinic acid, isododecenyl succinic acid and the like,
Examples thereof include acid anhydrides and lower monoalkyl esters.

Examples of the aliphatic diol as the component (D) include ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, pentaethylene glycol, 1,4-butanediol, 1,5-pentanediol and 1,6-hexane. Diol, 1,2-
Examples include propylene glycol, 1,3-propylene glycol, dipropylene glycol, neopentyl glycol and the like.

As the binder resin used in the toner constituting the developer for developing an electrostatic image of the present invention, in addition to the polyester resin, a copolymer of styrene and its substitution product; a styrene-methyl acrylate copolymer, Styrene-acrylic acid ester copolymers such as styrene-ethyl acrylate copolymer, styrene-n-butyl acrylate copolymer;
Styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-methacrylic acid n
-Copolymer of styrene and methacrylic acid ester such as butyl copolymer; Multi-component copolymer of styrene and acrylic acid ester and methacrylic acid ester; Other styrene-
Styrene such as acrylonitrile copolymer, styrene-vinyl methyl ether copolymer, styrene-butadiene copolymer, styrene-vinyl methyl ketone copolymer, styrene-acrylonitrile-indene copolymer, styrene-maleic acid ester copolymer Styrene-based copolymer of styrene and other vinyl-based monomer; polymethylmethacrylate,
Polybutyl methacrylate, polyvinyl acetate, polyamide, epoxy resin, polyvinyl butyral, polyacrylic acid, phenol resin, aliphatic or alicyclic hydrocarbon resin, petroleum resin, chlorinated paraffin, etc. can be used alone or in combination.

In the toner constituting the developer for developing an electrostatic image of the present invention, basically, additives such as a charge control agent, a release agent and a colorant are dispersed and contained in the above binder resin. It consists of particles.

In the present invention, a charge control agent can be used if necessary, and a conventionally known negative or positive charge control agent is used.

The charge control agents known in the art today include the following. The following substances control the toner to be negatively charged.

For example, organic metal complexes and chelate compounds are effective and there are monoazo metal complexes, acetylacetone metal complexes, aromatic hydroxycarboxylic acid and aromatic dicarboxylic acid type metal complexes as described above. Besides, aromatic hydroxycarboxylic acids, aromatic mono- and polycarboxylic acids and their metal salts, anhydrides and esters. Phenol derivatives such as bisphenol.

There are the following substances for controlling the toner to be positively charged.

Modified products with nigrosine and fatty acid metal salts; quaternary ammonium salts such as tributylbenzylammonium-1-hydroxy-4-naphthosulfonate and tetrabutylammonium tetrafluoroborate,
And onium salts such as phosphonium salts which are analogs thereof and lake pigments thereof; triphenylmethane dyes and lake pigments thereof (as a laker, phosphotungstic acid, phosphomolybdic acid, phosphotungsten molybdic acid, tannic acid) , Lauric acid, gallic acid, ferricyanide, ferrocyanide, etc.); metal salts of higher fatty acids; diorganotin oxides such as dibutyltin oxide, dioctyltin oxide, dicyclohexyltin oxide; dibutyltin borate, dioctyltin borate, dicyclohexyltin borate. Such as diorgano tin borate. These can be used alone or in combination of two or more. Of these, charge control agents such as nigrosine and quaternary ammonium salts are particularly preferably used.

Further, a wax-like substance such as low molecular weight polypropylene, microcrystalline wax, carnauba wax, sazol wax and paraffin wax is used as the binder resin 100 for the purpose of improving releasability at the time of heat roll fixing.
It is also one of the preferable modes of the present invention to add about 0.5 to 10% by weight to the toner.

The colorant that can be used in the toner of the present invention includes any appropriate pigment or dye. Toner colorants are well known, and examples of pigments include carbon black, aniline black, acetylene black, naphthol yellow, hansa yellow, rhodamine lake, alizarin lake, red iron oxide, phthalocyanine blue, and indanthrene blue. These are used in an amount necessary and sufficient for maintaining the optical density of the fixed image.
0.1 to 20 parts by weight, preferably 2 to 10 parts by weight
The addition amount of parts by weight is good. Further, a dye is further used for the same purpose. For example, there are azo dyes, anthraquinone dyes, xanthene dyes, methine dyes, etc. Resin 1
The amount of addition is 0.1 to 20 parts by weight, preferably 0.3 to 3 parts by weight, relative to 00 parts by weight.

In the toner of the present invention, the charging stability,
In order to improve developability, fluidity and durability, it is preferable to add fine silica powder.

The silica fine powder used in the present invention is BE.
The specific surface area by nitrogen adsorption measured by T method is 30m ² /
Those in the range of g or more (particularly 50 to 400 m ² / g) give good results. The fine silica powder is used in an amount of 0.01 to 8 parts by weight, preferably 0.1 to 5 parts by weight, based on 100 parts by weight of the toner.

Further, the silica fine powder used in the present invention contains, as required, silicone varnish, various modified silicone varnishes, silicone oil, various modified silicone oil, silane coupling agent, for the purpose of hydrophobizing and controlling the charging property. It is also preferable that the silane coupling agent having a functional group and the other treating agent such as an organic silicon compound are used in combination for the treatment.

Other additives include, for example, lubricants such as Teflon, zinc stearate and polyvinylidene fluoride,
Alternatively, abrasives such as cerium oxide, silicon carbide, and strontium titanate; or fluidity-imparting agents such as titanium oxide and aluminum oxide; anti-caking agents; or conductive materials such as carbon black, zinc oxide, antimony oxide, and tin oxide. A small amount of an imparting agent, or white and black fine particles having opposite polarities can be used as a developing property improver.

The developer for developing an electrostatic charge image of the present invention comprises a toner and a carrier, and the mixing ratio of the toner and the carrier is 2.0 to 12 parts by weight, preferably 0.5 to 8 parts by weight as a toner concentration. Is desirable.

As the carrier that can be used in the present invention, all known carriers can be used. For example, magnetic powder such as iron powder, ferrite powder, nickel powder, glass beads, etc. Examples thereof include those treated with resin, vinyl resin, silicon resin, or the like.

To prepare the toner according to the present invention, a binder resin, a metal salt or a metal complex, a pigment as a colorant or a dye, a charge control agent, if necessary, and other additives are added to a Henschel mixer or a ball mill. After sufficiently mixing with a mixer such as a heating roll, a kneader, using a heat kneader such as an extruder, kneading and kneading meat to make the resins compatible with each other in the metal compound, pigment, dye ,
Can be dispersed or dissolved, cooled and solidified, and then pulverized and classified to obtain the toner according to the present invention. Further, if desired, desired additives can be sufficiently mixed with a mixer such as a Henschel mixer to obtain the toner according to the present invention.

[0072]

EXAMPLES The present invention will be described below with reference to specific examples, but the present invention is not limited thereto. First, a synthesis example of the binder resin used in the present invention will be described. Aromatic dicarboxylic acid shown in Table 1 below, polyvalent monomer having a valence of 3 or more, alkyl or alkenyl succinic acid or its acid anhydride or its lower monoalkyl ester Aliphatic diol is put in a four-necked flask, and a stirrer and a thermometer are used. A nitrogen gas introduction tube was set and placed in the mantle heater. After replacing the inside of the reaction vessel with nitrogen gas, the mixture was heated and stirred at 210 ° C. to cause a reaction, to obtain binder resins of Synthesis Examples 1 to 8.

Acid value (AV), hydroxyl value (OHV), softening point (Tsp) and glass transition point (T) of the obtained binder resin.
g) is shown in Table 1.

[0074]

[Table 1] Here, the composition ratio of each monomer composition is shown by mol%.

[0075] After mixing well EXAMPLE 1 Synthesis Example (manufactured by Cabot Corporation) 100 parts by weight of the resin of 1 carbon black Mogaru L 10 parts by weight of the low molecular weight polypropylene 3 parts negatively chargeable charge control agent 2 parts by weight The above materials in a blender The mixture was kneaded with a twin-screw kneading extruder set at 150 ° C. The obtained kneaded product is cooled, roughly crushed with a cutter mill, crushed with a fine crusher using a jet stream, and further classified with an air classifier to obtain a black fine powder having a volume average particle diameter of 12 μm. Got

To 100 parts by weight of this black powder, 0.4 parts by weight of negatively charged hydrophobic dry colloidal silica was added and mixed with a Henschel mixer, and then carrier iron powder (TEFV2
00/300, manufactured by Nippon Iron Powder Co., Ltd.) to obtain a developer for developing an electrostatic charge image.

This electrostatic image developing agent was applied to a commercially available Canon copying machine NP-8580, and was subjected to normal temperature and normal humidity (23.5 ° C.,
60%), low temperature and low humidity (15 ° C, 10%), high temperature and high humidity (3
Under each environmental condition (2.5 ° C., 85%), the image is output 150,000 times in the intermittent mode in which the operation of the device is stopped each time one copy image is formed, not in the continuous mode. It was

In any of the environments, the charge amount on the sleeve was stable even after repeated 150,000 copies, there was no significant change in image quality, there were no problems with background fog and image disturbance, and no cleaning failure occurred. .. Table 2 shows a summary of the evaluation results.

Further, the evaluation of the pulverizability at the time of producing the toner was carried out by the following procedure.

When manufacturing a toner, various raw materials are mixed, melted and kneaded, the kneaded product is cooled, coarsely pulverized by a cutter mill, and then finely pulverized by a fine pulverizer using a jet stream. The crushing air pressure of the fine crusher was 6.
Volume average particle diameter of 8.0 when fixed at 0 kgf / cm ^2.
The pulverization feed amount (shown in kg / h) per hour at which a fine powder of μm was obtained was used as an index of pulverizability. The evaluation of pulverizability was not practically possible when the pulverizability was less than 3.0 kg / h.

The blocking property is about 1 g of toner of about 10 g.
The state of aggregation when placed in a 00 cc poly cup and left at 50 ° C. for 3 days was visually determined.

The fixing property and the offset property were evaluated by the following procedures.

The fixability is measured in a low temperature and low humidity environment (15 ° C., 10
%), The evaluation machine is left to stand overnight, and the evaluation machine and the fixing device inside the evaluation machine are completely acclimated to the environment of low temperature and low humidity.
00 sheets of copied images were taken, and the 200th sheet of the copied image was used for evaluation of fixing property. The fixing property was evaluated by rubbing the image with sillbon paper 10 times in a reciprocating manner under a load of about 100 g, and peeling of the image was evaluated by a reduction rate (%) of reflection density.

With respect to the offset property, the cleaning mechanism of the fixing roller was removed, and the number of copies for which the image was soiled or the roller was soiled was evaluated based on the number of copy resistant sheets.

Further, since the toner once taken in the cleaning wave may be transferred to the upper roller due to the dirt of the cleaning wave during continuous copying, and the copy may be contaminated. After returning the cleaning mechanism of the fixing roller to the normal state, raising the set temperature of the fixing device by 5 ° C. and taking 200 consecutive copy images, one copy image is taken at intervals of 30 seconds for up to 3 minutes.
It was examined whether image contamination occurred, and the state of stain on the cleaning wave of the fixing roller was evaluated.

In the present invention, the fine line reproducibility was measured by the following method. That is, an image obtained by copying an original of a fine line having a width of 100 μm accurately under an appropriate copying condition is used as a measurement sample, and using a Luzex 450 particle analyzer as a measuring device, a line width is displayed by an indicator from an enlarged monitor image. Measure. At this time, since the line width measurement position has unevenness in the width direction of the thin line image of the toner, the average line width of the unevenness is used as the measurement point. From this, the fine line reproducibility value (%) is calculated by the following formula.

[0087]

[Equation 2] Example 2 Resin of Synthesis Example 2 100 parts by weight Carbon black # 30 (manufactured by ORIUND CHEMICAL CO., LTD.) 5 parts by weight Low molecular weight polypropylene 3 parts by weight Negatively charged charge control agent 2 parts by weight The above materials were treated in the same manner as in Example 1. Then, mixing, kneading, pulverization and classification were carried out to obtain a black fine powder having a volume average particle diameter of 8.0 μm.

To 100 parts by weight of this black powder, 0.6 parts by weight of negatively charged hydrophobic dry colloidal silica was added and mixed with a Henschel mixer, and then carrier iron powder (TEFV2
00/300, manufactured by Nippon Iron Powder Co., Ltd.) to obtain a developer for developing an electrostatic charge image.

This electrostatic charge image developing developer was evaluated in the same manner as in Example 1.

In any of the environments, the charge amount on the sleeve was stable even after repeated 150,000 copies, there was no significant change in image quality, there were no problems with background fog and image disturbance, and no cleaning failure occurred. .. Table 2 shows a summary of the evaluation results.

[0091] the same manner as in Example 3 resin 100 parts by weight of carbon black in Synthesis Example 3 Mogaru L (manufactured by Cabot Corporation) Example 1 15 parts by weight low molecular weight polypropylene 3 parts negatively chargeable charge control agent 2 parts by weight These materials By the method, mixing, kneading, pulverization and classification were carried out to obtain a black fine powder having a volume average particle diameter of 8.0 μm.

To 100 parts by weight of this black powder, 0.6 parts by weight of negatively charged hydrophobic dry colloidal silica was added and mixed with a Henschel mixer, and then carrier iron powder (TEFV2
00/300, manufactured by Nippon Iron Powder Co., Ltd.) to obtain a developer for developing an electrostatic charge image.

This electrostatic charge image developing developer was evaluated in the same manner as in Example 1.

In any of the environments, the charge amount on the sleeve was stable even after repeated 150,000 copies, there was no significant change in image quality, there was no problem with background fog and image disturbance, and no cleaning failure occurred. .. Table 2 shows a summary of the evaluation results.

Example 4 Resin of Synthesis Example 1 100 parts by weight carbon black Mogul L (manufactured by Cabot) 10 parts by weight Low molecular weight polypropylene 3 parts by weight Positively chargeable charge control agent 2 parts by weight The above materials were the same as in Example 1. By the method, mixing, kneading, pulverization and classification were carried out to obtain a black fine powder having a volume average particle size of 12.0 μm.

To 100 parts by weight of this black powder, 0.4 parts by weight of positively charged hydrophobic dry colloidal silica was added and mixed with a Henschel mixer, and then carrier iron powder (TEFV2
00/300, manufactured by Nippon Iron Powder Co., Ltd.) to obtain a developer for developing an electrostatic charge image.

This electrostatic charge image developing developer was applied to a commercially available Canon copying machine NP-5540, and the same evaluation as in Example 1 was carried out.

In any of the environments, the charge amount on the sleeve was stable even after repeated 150,000 copies, there was no significant change in image quality, there was no problem with background fog and image disturbance, and no cleaning failure occurred. .. Table 2 shows a summary of the evaluation results.

Example 5 Resin of Synthesis Example 2 100 parts by weight Carbon black Mogul L (manufactured by Cabot) 10 parts by weight Low molecular weight polypropylene 3 parts by weight Positively chargeable charge control agent 2 parts by weight The above materials were the same as in Example 1. By the method, mixing, kneading, pulverization and classification were carried out to obtain a black fine powder having a volume average particle diameter of 12.2 μm.

To 100 parts by weight of this black powder, 0.4 parts by weight of positively charged hydrophobic dry colloidal silica was added and mixed with a Henschel mixer, and then carrier iron powder (TEFV2
00/300, manufactured by Nippon Iron Powder Co., Ltd.) to obtain a developer for developing an electrostatic charge image.

This electrostatic image developer was applied to a commercially available Canon copying machine NP-5540 and the same evaluation as in Example 1 was carried out.

In any of the environments, the charge amount on the sleeve was stable even after repeated 150,000 copies, there was no significant change in image quality, there were no problems with background fog and image disturbance, and no cleaning failure occurred. .. Table 2 shows a summary of the evaluation results.

Comparative Example 1 Resin of Synthesis Example 4 100 parts by weight Carbon black Mogul L (manufactured by Cabot) 10 parts by weight Low molecular weight polypropylene 3 parts by weight Negatively charged charge control agent 2 parts by weight The above materials were the same as in Example 1. By the method, mixing, kneading, pulverization and classification were carried out to obtain a black fine powder having a volume average particle size of 12.0 μm.

To 100 parts by weight of this black powder, 0.4 parts by weight of negatively charged hydrophobic dry colloidal silica was added and mixed with a Henschel mixer, and then carrier iron powder (TEFV2
00/300, manufactured by Nippon Iron Powder Co., Ltd.) to obtain a developer for developing an electrostatic charge image.

The electrostatic charge image developing developer was evaluated in the same manner as in Example 1.

Under normal temperature and normal humidity and low temperature and low humidity environment, 1
The amount of electrostatic charge on the sleeve was stable even after repeated copying of 50,000 times, there was no significant change in image quality, and there were no problems with background fog and image disturbance, but it was durable in a high temperature and high humidity environment.
Toner was fused to the drum near the 00th sheet, and cleaning failure occurred. Therefore, in a high temperature and high humidity environment, 130
The durability was stopped at around 00 sheets.

Further, the level of blocking resistance of the toner is insufficient.

Table 2 shows a summary of the evaluation results. As for the offset property, the number of copy-resistant sheets was 25, and the result was inferior in the offset property.

Comparative Example 2 Resin of Synthesis Example 5 100 parts by weight Carbon black Mogul L (manufactured by Cabot) 10 parts by weight Low molecular weight polypropylene 3 parts by weight Negatively charged charge control agent 2 parts by weight The above materials were the same as in Example 1. By the method, mixing, kneading, pulverization and classification were carried out to obtain a black fine powder having a volume average particle size of 12.0 μm.

To 100 parts by weight of this black powder, 0.4 parts by weight of negatively charged hydrophobic dry colloidal silica was added and mixed with a Henschel mixer, and then carrier iron powder (TEFV2
00/300, manufactured by Nippon Iron Powder Co., Ltd.) to obtain a developer for developing an electrostatic charge image.

This electrostatic charge image developing developer was evaluated in the same manner as in Example 1.

In any of the environments, the charge amount on the sleeve was stable even after repeated 150,000 copies, there was no significant change in image quality, there were no problems with background fog and image disturbance, and no cleaning failure occurred. ..

However, the grindability is 2.5 kg / h, and the level of grindability is insufficient. Also, the fixability is 35.7.
%, And the result was inferior in fixability. Further, the offset property was inferior in image stain and wave stain.

Table 2 shows a summary of the evaluation results.

Comparative Example 3 Resin of Synthesis Example 6 100 parts by weight Carbon black Mogul L (manufactured by Cabot) 10 parts by weight Low molecular weight polypropylene 3 parts by weight Negatively charged charge control agent 2 parts by weight The above materials were the same as in Example 1. By the method, mixing, kneading, pulverization and classification were carried out to obtain a black fine powder having a volume average particle size of 12.0 μm.

To 100 parts by weight of this black powder, 0.4 parts by weight of negatively-charged hydrophobic dry colloidal silica was added and mixed with a Henschel mixer, and then carrier iron powder (TEFV2
00/300, manufactured by Nippon Iron Powder Co., Ltd.) to obtain a developer for developing an electrostatic charge image.

This electrostatic charge image developing developer was evaluated in the same manner as in Example 1.

In a normal temperature and normal humidity environment, the charge amount on the sleeve is stable even after 150,000 copies, no significant change in image quality occurs, no background fog or image disturbance occurs, and cleaning failure occurs. There wasn't. However, during the durability test under high temperature and high humidity environment, the toner was fused to the drum around 27,000 sheets, and cleaning failure occurred. Therefore, under high temperature and high humidity environment, the durability was stopped around 27,000 sheets.

The offset property is that the number of copy-resistant sheets is 5
The number of sheets and wave stains is at a level of Δ, which is a level having some problems in practical use. Table 2 shows a summary of the evaluation results.

Comparative Example 4 Resin of Synthesis Example 7 100 parts by weight Carbon black Mogul L (manufactured by Cabot) 10 parts by weight Low molecular weight polypropylene 3 parts by weight Negatively charged charge control agent 2 parts by weight The above materials were the same as in Example 1. By the method, mixing, kneading, pulverization and classification were carried out to obtain a black fine powder having a volume average particle size of 12.0 μm.

To 100 parts by weight of this black powder, 0.4 parts by weight of negatively charged hydrophobic dry colloidal silica was added and mixed with a Henschel mixer, and then carrier iron powder (TEFV2
00/300, manufactured by Nippon Iron Powder Co., Ltd.) to obtain a developer for developing an electrostatic charge image.

The electrostatic charge image developing developer was evaluated in the same manner as in Example 1.

Under normal temperature and normal humidity and high temperature and high humidity environment, 1
The amount of electrostatic charge on the sleeve was stable even after repeated copying of 50,000 times, there was no significant change in image quality, there were no problems with background fog and image disturbance, and cleaning defects did not occur.
However, during running in a low temperature and low humidity environment, image distortion and fog became a problematic level for practical use, and the image density began to drop from around 83000 sheets and the image density at the time of running 87,000 sheets was 1.12. At some point the durability was stopped.

Also, during the durability test, cleaning failure occurred near 81,000 sheets.

Further, both the fixing property and the offset property are at practically problematic levels. Table 2 shows a summary of the evaluation results.

Comparative Example 5 Resin of Synthesis Example 8 100 parts by weight Carbon black Mogall L (manufactured by Cabot) 10 parts by weight Low molecular weight polypropylene 3 parts by weight Negatively charged charge control agent 2 parts by weight The above materials were the same as in Example 1. By the method, mixing, kneading, pulverization and classification were carried out to obtain a black fine powder having a volume average particle size of 12.0 μm.

To 100 parts by weight of this black powder, 0.4 parts by weight of negatively chargeable hydrophobic dry colloidal silica was added and mixed with a Henschel mixer, and then carrier iron powder (TEFV2
00/300, manufactured by Nippon Iron Powder Co., Ltd.) to obtain a developer for developing an electrostatic charge image.

This electrostatic charge image developing developer was evaluated in the same manner as in Example 1.

In a normal temperature and normal humidity environment, the charge amount on the sleeve is stable even after repeated 150,000 copies, there is no large change in image quality, there is no problem with background fog and image disturbance, and cleaning failure occurs. There wasn't. However, during running in a low temperature and low humidity environment, image distortion and fog are at a problematic level, and the image density starts to drop from around 80,000 sheets, and the image density at the time of running 83,000 sheets was 1.09. I stopped the endurance.

The pulverizability is 2.6 kg / h, which is a practically problematic level.

The fixability is 36.2%, which is a practically problematic level.

The offset property is a level at which there is a problem in practical use even when image contamination occurs and wave stains occur.

Table 2 shows a summary of the evaluation results.

[0134]

[Table 2]

[0135]

According to the present invention, by using a specific polyester as the binder resin, the triboelectric charge amount is appropriate under a low temperature and low humidity environment even when applied to a high-speed machine, and the durability and the cleaning property are improved. It is possible to obtain an electrostatic charge image developing developer which is excellent in fine line reproducibility and is excellent in fixability under low temperature and low humidity environmental conditions, pulverizability during toner production, blocking resistance and the like.

Front Page Continuation (72) Inventor Yoshinobu Castle 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Kyohisa Akashi 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. Within

Claims (2)

[Claims] 1. A developer for electrostatic charge image development containing a toner and a carrier, wherein (A) aromatic dicarboxylic acid (B) trivalent or higher polyvalent monomer (C) alkyl is used as a binder resin for the toner. Alternatively, a developer characterized by using a polyester obtained by polycondensing a monomer composition containing alkenylsuccinic acid or an acid anhydride thereof or a lower monoalkyl ester (D) aliphatic diol thereof. 2. The component (A) is 50 in the monomer composition.
Mol% or less, component (B) is 40 mol% or less, component (C)
Is 10 to 25 mol% and the component (D) is 45 to 60 mol%. The developer for developing an electrostatic charge image according to claim 1, wherein