JP2001027821A - Electrostatic charge image developing toner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrostatie charge image developing toner excellent in fixability and anti-offsetting property. SOLUTION: The electrostatic charge image developing toner comprises aggregates of particles containing at least primary particles of a polymer, which have a structure which substantially includes a wax and is obtained by seed polymerization using a wax emulsion whose average particle diameter is preferably 0.01-3 μm as seed particles.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrostatic image developing toner used in an electrophotographic copying machine and a printer. More specifically, fixing properties, offset resistance,
Excellent blocking resistance, gloss of the obtained image, OH
The present invention relates to a toner for developing electrostatic images having good P transparency.

[0002]

2. Description of the Related Art Toners for developing electrostatic images, which have been widely used in electrophotography, have been used in combination with a styrene / acrylate copolymer, a coloring agent such as carbon black or a pigment, a charge controlling agent and / or a magnetic material. It has been manufactured by melt-kneading a mixture containing a body with an extruder, followed by pulverization and classification. However, the conventional toner obtained by the above-described melt-kneading / pulverizing method has a limitation in controlling the particle size of the toner, and it is necessary to produce a toner having an average particle size of substantially 10 μm or less, particularly 8 μm or less with high yield. However, it cannot be said that it is sufficient to achieve the high resolution required for electrophotography in the future.

In order to achieve low-temperature fixability, a method has been proposed in which a wax having a low softening point is blended into a toner during kneading. However, in a kneading / pulverizing method, a blend of about 5% is limited. Thus, a toner having a sufficient low-temperature fixing performance could not be obtained. JP-A-63-186253
In order to overcome the problem of particle size control and achieve high resolution, Japanese Patent Application Laid-Open Publication No. H11-15064 proposes a method for producing a toner by an emulsion polymerization / aggregation method. However, even in this method, the amount of wax that can be introduced in the aggregation step is limited, and a sufficient improvement effect on low-temperature fixability has not been obtained.
That is, based on the patent, the present inventors examined the amount of added wax, and as the amount of added wax was increased, the particle size distribution of the obtained toner became two peaks or 1 μm or less. There is a problem that fine powder remains, and a classification step is required after the aggregation step. JP-A-6-329
The method disclosed in Japanese Patent No. 947 is a method capable of obtaining aggregated particles having a narrow particle size distribution by adding an organic solvent which is infinitely soluble in water at the same time as an aggregating agent in the aggregating step. There are problems such as poor reproducibility due to the large number, and a heavy burden on wastewater treatment.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a novel toner which overcomes the drawbacks of the conventional electrostatic image developing toners and satisfies high resolution, low-temperature fixability and offset resistance. With the goal.

[0005]

Means for Solving the Problems As a result of intensive studies on the above problems, the present inventors have found that the above problems can be solved by using polymer primary particles obtained by emulsion polymerization using a wax emulsion as a seed. Reached the present invention. That is, the present invention mainly relates to a toner for developing an electrostatic image composed of a particle aggregate containing at least polymer primary particles, wherein the polymer primary particles have a structure substantially containing wax therein. The toner for developing an electrostatic image, characterized by the sequential addition of a monomer mixture containing a monomer having an acidic polar group or a basic polar group in the presence of a wax to perform seed emulsion polymerization, and then the obtained polymer primary particles Mixing the dispersion and a dispersion containing primary colorant particles and / or charge control agent particles,
The present invention relates to a method for producing a toner for developing an electrostatic image, characterized in that particles are aggregated to form associated particles.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
As the wax used as a seed in the present invention, any of known waxes can be used.Specifically, low molecular weight polyethylene, low molecular weight polypropylene, olefinic wax such as copolymerized polyethylene, paraffin wax, Behenyl behenate, montanic acid ester, ester wax having a long chain aliphatic group such as stearyl stearate, vegetable wax such as hydrogenated castor oil carnauba wax, ketone having a long chain alkyl group such as distearyl ketone, alkyl group And silicones having higher fatty acids such as stearic acid, higher-chain fatty acid alcohols, longer-chain fatty acid polyhydric alcohols such as pentaerythritol, and their partial esters, oleic amides, higher fatty acid amides such as stearic amide, and the like. You. Among these waxes, those having a melting point of 100 ° C. or less are more preferable for improving the fixing property, and the melting points of the wax are more preferably in the range of 40 to 90 ° C., and particularly preferably in the range of 50 to 80 ° C. It is. If the melting point exceeds 100 ° C., the effect of lowering the fixing temperature becomes poor.

The wax fine particles used in the present invention are obtained by emulsifying the above wax in the presence of at least one emulsifier selected from known cationic surfactants, anionic surfactants and nonionic surfactants. Two or more of these surfactants may be used in combination. Specific examples of the cationic surfactant include dodecyl ammonium chloride, dodecyl ammonium bromide, dodecyl trimethyl ammonium bromide, dodecyl pyridinium chloride, dodecyl pyridinium bromide, hexadecyl trimethyl ammonium bromide, and the like.

Specific examples of the anionic surfactant include sodium stearate, sodium dodecanoate,
And sodium dodecyl sulfate, sodium dodecylbenzenesulfonate, sodium lauryl sulfate and the like.

Further, specific examples of the nonionic surfactant include dodecyl polyoxyethylene ether, hexadecyl polyoxyethylene ether, nonylphenyl polyoxyethylene ether, lauryl polyoxyethylene ether, sorbitan monooleate polyoxyethylene ether, And monodecanoyl sucrose.

In the present invention, these waxes are dispersed in the presence of an emulsifier to form an emulsion, which is subjected to resin seed polymerization. The average particle size of the wax emulsion is 0.0
It is preferably 1 μm to 3 μm, more preferably 0.03 μm.
１1 μm, especially 0.05-0.8 μm is suitably used. The average particle size can be measured, for example, using a Microtrack UPA manufactured by Nikkiso Co., Ltd. If the average particle size of the wax emulsion is larger than 3 μm, the average particle size of the polymer particles obtained by seed polymerization becomes too large, and is not suitable for applications requiring high resolution as a toner. When the average particle size of the emulsion is smaller than 0.01 μm, the wax content in the polymer primary particles after the seed polymerization becomes too low, and the effect of the wax is reduced.

In performing the seed emulsion polymerization in the presence of the wax emulsion, a monomer having a polar group (a monomer having an acidic polar group or a monomer having a basic functional group) and other monomers must be sequentially added. Thereby, the polymerization proceeds in the emulsion containing the wax. At this time, the monomers may be added separately, or a plurality of monomers may be mixed in advance and added. Further, the monomer composition can be changed during the addition of the monomer. Further, the monomer may be added as it is, or may be added as an emulsified liquid which is previously mixed and adjusted with water or a surfactant. As the surfactant, one or more of the above surfactants are used in combination.

In carrying out the seed emulsion polymerization,
A certain amount of an emulsifier may be added to the wax emulsion. The timing of adding the polymerization initiator may be before adding the monomer, simultaneously adding the monomer, or after adding the monomer, or may be a combination of these adding methods.

The polymer primary particles obtained as described above are polymer particles substantially containing wax. The morphology of the primary particles is any of core-shell type, phase separation type, occlusion type and the like. It may be in the form or a mixture of these forms. Particularly preferred is the core-shell type. The wax is usually used in an amount of 1 to 4 parts by weight per 100 parts by weight of the binder resin.
0 parts by weight, preferably 2 parts by weight to 35 parts by weight, more preferably 5 parts by weight to 30 parts by weight. In addition, a component other than the wax, for example, a pigment, a charge control agent, or the like may be used as a seed at the same time as long as the gist of the present invention is not deviated. Further, a colorant may be used by dissolving or dispersing it in a monomer or wax.

The monomer having an acidic polar group used in the present invention includes a monomer having a carboxyl group such as acrylic acid, methacrylic acid, maleic acid, fumaric acid, and cinnamic acid, and a sulfonic acid group such as sulfonated styrene. And the like.

Examples of the monomer having a basic polar group include aminostyrene and quaternary salts thereof, nitrogen-containing heterocyclic-containing monomers such as vinylpyridine and vinylpyrrolidone, and amino acids such as dimethylaminoethyl acrylate and diethylaminoethyl methacrylate. Group-containing (meth) acrylates and these amino groups
(Meth) acrylic acid ester having a graded ammonium salt, furthermore, acrylamide, N-propylacrylamide, N, N-dimethylacrylamide, N, N-
Examples thereof include dipropylacrylamide, N, N-dibutylacrylamide and acrylamide.

Other comonomers include styrene,
Methyl styrene, chlorostyrene, dichlorostyrene,
styrenes such as p-tert-butylstyrene, pn-butylstyrene, pn-nonylstyrene, methyl acrylate, ethyl acrylate, propyl acrylate,
N-butyl acrylate, isobutyl acrylate, hydroxyethyl acrylate, ethyl hexyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, hydroxyethyl methacrylate, ethylhexyl methacrylate, (Meth) acrylic acid esters. Among them, styrene, butyl acrylate and the like are particularly preferred.

These monomers are used singly or as a mixture. In this case, the polymer has a glass transition temperature of 40.
The temperature is preferably -80 ° C. Glass transition temperature 80
If the temperature exceeds 100 ° C., the fixing temperature may become too high, or the OHP transparency may deteriorate. On the other hand, if the glass transition temperature of the polymer is lower than 40 ° C., the storage stability of the toner becomes too poor. Cause problems. In the present invention, acrylic acid is preferably used as a monomer having an acidic polar group, and styrene, acrylate, and methacrylate are preferably used as other monomers.

Examples of the polymerization initiator include persulfates such as potassium persulfate, sodium persulfate, and ammonium persulfate;
And a redox initiator combining these persulfates as a component with a reducing agent such as sodium acid sulfite, hydrogen peroxide, 4,4′-azobiscyanovaleric acid, t-butyl hydroperoxide, cumene hydroperoxide, etc. Water-soluble polymerization initiator, and a redox initiator system in which these water-soluble polymerization initiators are combined as one component with a reducing agent such as a ferrous salt, benzoyl peroxide, 2,2′-
Azobis-isobutyronitrile and the like are used. These polymerization initiators may be added to the polymerization system at any time before, simultaneously with, or after the addition of the monomers, and these addition methods may be combined as necessary.

In the present invention, known chain transfer agents can be used if necessary. Specific examples of such chain transfer agents include t-dodecyl mercaptan, 2-mercaptoethanol, diisopropylxanthogen and the like. , Carbon tetrachloride, trichlorobromomethane, and the like.
The chain transfer agent may be used alone or in combination of two or more kinds, and is used in an amount of 0 to 5% by weight based on the polymerizable monomer.

The average particle size of the polymer primary particles is usually 0.0
5 μm to 3 μm, preferably 0.1 μm to
It is 1 μm, more preferably 0.1 μm to 0.5 μm. The average particle size can be measured using, for example, UPA. When the particle size is smaller than 0.05 μm, it is difficult to control the coagulation speed, which is not preferable. 3μm
If it is larger, the particle size of the toner obtained by agglomeration becomes too large, which is not suitable for applications requiring high resolution as a toner.

In the present invention, when the polymer primary particles are obtained, the pigment may be used as a seed simultaneously with the wax, or the colorant may be used by dissolving or dispersing it in a monomer or wax. At the same time, it is preferable that the primary particles of the colorant are aggregated to form associated particles to obtain a toner. At this time, polymer primary particles containing wax are used, but two or more types of polymer primary particles may be used as necessary. The colorant used here may be any of an inorganic pigment, an organic pigment, an organic dye, or a combination thereof. Specific examples of these include carbon black, aniline blue,
Any known dyes and pigments such as phthalocyanine blue, phthalocyanine green, Hansa yellow, rhodamine dyes, chrome yellow, quinacridone, benzidine yellow, rose bengal, triallylmethane dyes, monoazo dyes, disazo dyes and condensed azo dyes Can be used alone or as a mixture. In the case of a full-color toner, it is preferable to use benzidine yellow, monoazo-based and condensed azo-based dyes and pigments for yellow, quinacridone and monoazo-based dyes and pigments for magenta, and phthalocyanine blue for cyan, respectively. The coloring agent is usually a binder resin 100
It is used in an amount of 3 to 20 parts by weight based on parts by weight.

These colorants are also used in the form of an emulsion by emulsifying the same in water in the presence of an emulsifier, and preferably have an average particle size of 0.01 to 3 μm.
Any known charge control agent can be used alone or in combination. Considering the color toner adaptability (the charge control agent itself is colorless or light color and there is no color hindrance to the toner), a quaternary ammonium salt compound is used as the positive charge, and chromium of salicylic acid or alkyl salicylic acid is used as the negative charge. Salts, metal complexes with zinc, aluminum, etc., metal salts of benzylic acid, metal complexes, amide compounds, phenol compounds, naphthol compounds, phenolamide compounds and the like are preferred. The amount used may be determined depending on the desired charge amount of the toner,
Usually, 0.01 to 1 with respect to 100 parts by weight of the binder resin.
0 parts by weight, more preferably 0.1 to 10 parts by weight.

In the present invention, when obtaining polymer primary particles,
Using a charge control agent as a seed simultaneously with wax,
The charge control agent may be used by dissolving or dispersing it in the monomer or wax, but it is preferable to form the associated particles by aggregating the primary particles of the charge control agent simultaneously with the primary particles of the polymer to form a toner. In this case, the charge control agent is also used in water as an emulsion having an average particle size of 0.01 to 3 μm. The timing of the addition may be simultaneously added and agglomerated in the step of aggregating the polymer primary particles and the colorant primary particles, or may be added at a stage where these primary particles are associated and secondary particles are generated. Alternatively, it may be added after the associated particles have grown to a final particle size of the toner.

In producing the toner of the present invention,
After the particle size of the agglomerated particles has substantially grown to the final particle size of the toner, the same or a different type of binder resin emulsion is further added, and the particles are adhered to the surface to improve the toner properties near the surface. It is also possible to modify. Further, the toner of the present invention can be used together with an additive such as a fluidizing agent, if necessary. Specific examples of such a fluidizing agent include fine particles such as hydrophobic silica, titanium oxide, and aluminum oxide. Powder, which is usually
It is used in an amount of 0.01 to 5 parts by weight, preferably 0.1 to 3 parts by weight, based on 100 parts by weight of the binder resin.

Further, the toner of the present invention contains an inorganic fine powder such as magnetite, ferrite, cerium oxide, strontium titanate, and conductive titania; a resistance regulator such as styrene resin and acrylic resin; a lubricant; Used as an additive. The amount of these additives used may be appropriately selected depending on the desired performance, and usually about 0.05 to 10 parts by weight per 100 parts by weight of the binder resin is suitable.

The electrostatic image developing toner of the present invention may be used in the form of either a two-component developer or a non-magnetic one-component developer. When used as a two-component developer, the carrier may be a magnetic substance such as iron powder, magnetite powder, or ferrite powder, or a carrier whose surface is coated with a resin, or a known carrier such as a magnetic carrier. As the coating resin for the resin-coated carrier, generally known styrene resins, acrylic resins, styrene-acryl copolymer resins, silicone resins, modified silicone resins, fluororesins, and mixtures thereof can be used.

[0027]

The present invention will be specifically described below with reference to examples. In the following examples, “parts” means “parts by weight”. The average particle size and molecular weight of the polymer particles were measured by the following methods. Average particle size: It was measured by Microtrac UPA manufactured by Nikkiso Co., Ltd. or Coulter Counter Multisizer II manufactured by Coulter Co., Ltd. Weight average molecular weight: measured by gel permeation chromatography (GPC). (Solvent: THF, calibration curve: standard polystyrene)

The obtained toner was subjected to a fixing test by the following method. A recording sheet carrying an unfixed toner image was prepared, the surface temperature of the heating roller was changed from 100 ° C. to 190 ° C., the sheet was conveyed to a fixing nip portion, and the fixing state when discharged was observed. The temperature region where the toner on the recording paper for fixing is sufficiently adhered to the recording paper without causing toner offset on the heating roller at the time of fixing is defined as a fixing temperature region.
The lower limit temperature of the fixing temperature at which this offset does not occur is TL,
When the upper limit temperature is TU, TU-TL is defined as the fixing temperature range. The following fixing method 1 or 2 was used. (Method 1) The heating roller of the fixing machine was evaluated with a release layer made of FEP and a nip width of 5 mm. (Method 2) In the heating roller of the fixing machine, the release layer was made of PFA (tetrafluoroethylene-perfluoroalkylvinyl ether copolymer), and the nip width was evaluated at 4 mm.

Example 1 <Production of polymer primary particles> The following wax emulsion and demineralized water were charged into a glass reactor equipped with a stirrer, a heating / cooling device, a concentrating device, and a raw material / auxiliary charging device. The temperature was raised to 90 ° C. under a nitrogen stream.

[0030]

Table 1 Behenyl behenate emulsion (average particle size 0.4 μm) 21.3 parts (as solid content) Deionized water (including water in wax emulsion) 404.9 parts

Thereafter, the following monomers, emulsifier aqueous solution and initiator were added, and emulsion polymerization was carried out for 5 hours.

[0032]

(Monomers) Styrene 64 parts Butyl acrylate 36 parts Acrylic acid 3 parts Trichlorobromomethane 1.3 parts Emulsifier aqueous solution 12 parts (Initiator) 2% hydrogen peroxide aqueous solution 43.0 parts 2% ascorbic acid aqueous solution 43.0 copies

After the completion of the polymerization reaction, the mixture was cooled to obtain a milky white polymer primary particle emulsion. (Hereinafter, it is abbreviated as resin emulsion A.) The average particle size of the obtained emulsion was 257 nm, and the weight average molecular weight of the polymer was 42,000. When a cross section of the obtained emulsion was observed with a TEM, it was observed that the wax was encapsulated in the resin. <Formation of associated particles (preparation of toner) and evaluation>

[0034]

TABLE 3 Resin Emulsion A 120 parts (as solid content) Charge control agent Bontron S-34 (10% dispersion) 0.65 parts (as solid content) phthalocyanine blue aqueous dispersion 6.7 parts (solid content) As)

An aqueous sodium chloride solution (9 parts as solid content) was added to the above mixture while dispersing and stirring with a disperser, and the mixture was kept at 20 ° C. for 1.5 hours. Thereafter, while further stirring, the temperature was raised to 45 ° C. and maintained for 0.5 hour, and further to 95 ° C. and maintained for 5 hours in order to further increase the bonding strength of the associated particles. Thereafter, the obtained slurry of associated particles is cooled,
The resulting mixture was filtered through a Kiriyama funnel, washed with water, and freeze-dried to obtain a toner having an average particle size of 6.9 μm. The toner thus obtained was evaluated by method 2 to find that the toner had a temperature of 115 to 190 ° C.
This was fixed.

Example 2 A resin emulsion (referred to as a resin emulsion B) using a purified paraffin (average particle size: 0.42 μm) emulsified with a nonionic surfactant as a wax emulsion.
Were prepared in the same manner as in Example 1 except that a resin emulsion and toner particles were produced. The toner thus obtained had an average particle size of 6.1 μm, and when evaluated by Method 2, it was fixed at 100 to 190 ° C. or higher.

Example 3 <Production of polymer primary particles> The following wax emulsion and demineralized water were charged into a glass reactor equipped with a stirrer, a heating / cooling device, a concentrating device, and a device for charging raw materials and auxiliaries. The temperature was raised to 90 ° C. under a nitrogen stream.

[0038]

Table 4 Behenyl behenate emulsion (average particle size 0.8 μm) 10.6 parts (as solid content) Deionized water (including water in wax emulsion) 352.3 parts

Thereafter, the following monomers, an aqueous emulsifier solution and an initiator were added, and emulsion polymerization was carried out for 5 hours.

[0040]

(Table 5) (Monomers) Styrene 75 parts Butyl acrylate 25 parts Acrylic acid 3 parts Trichlorobromomethane 0.5 parts Emulsifier aqueous solution 26 parts (Initiator) 2% hydrogen peroxide aqueous solution 43.2 parts 2% ascorbic acid aqueous solution 43.2 copies

After the completion of the polymerization reaction, the mixture was cooled to obtain a milky white polymer primary particle emulsion. (Hereinafter, it is abbreviated as resin emulsion C.) The average particle diameter of the obtained emulsion was 244 nm, and the weight average molecular weight of the polymer was 59000. When a cross section of the obtained emulsion was observed with a TEM, it was observed that the wax was encapsulated in the resin. <Formation of associated particles (preparation of toner) and evaluation>

[0042]

TABLE 6 Resin emulsion C 110 parts (as solid content) Charge control agent phenolamide compound (20% dispersion) 0.65 parts (as solid content) Phthalocyanine blue aqueous dispersion 6.7 parts (solid content) As

While dispersing and stirring the above mixture with a disperser, an aqueous solution of aluminum sulfate (0.4 wt.
And the mixture was kept at 20 ° C. for 1.5 hours. Thereafter, the temperature was raised to 60 ° C. with further stirring and maintained for 0.5 hour, and further raised to 95 ° C. for 5 hours to further increase the bonding strength of the associated particles.
Hold for hours. Thereafter, the obtained slurry of associated particles was cooled, filtered through a Kiriyama funnel, washed with water, and freeze-dried to obtain a toner. When the toner thus obtained was evaluated by Method 2, it was fixed at 140 to 190 ° C. or higher.

Comparative Example 1 <Production of Primary Polymer Particles> The following emulsifier and demineralized water were charged into a glass reactor equipped with a stirrer, a heating / cooling device, a concentrating device, and a device for charging raw materials and auxiliaries. Except for the above, emulsion polymerization was carried out in the same manner as in Example 3.

[0045]

Table 7 Dodecylbenzenesulfonic acid 0.3 part Deionized water (including water in wax emulsion) 315.3 parts

After the completion of the polymerization reaction, the mixture was cooled to obtain a milky white polymer primary particle emulsion. (Hereinafter, it is abbreviated as resin emulsion D.) The average particle diameter of the obtained emulsion was 219 nm, and the weight average molecular weight of the polymer was 60000.

<Formation of Associated Particles (Preparation of Toner) and Evaluation> Resin emulsion C was replaced with resin emulsion D100.
Toner particles were produced in the same manner as in Example 3 except that 10 parts (as a solid content) and 10 parts (as a solid content) of a behenyl behenate emulsion emulsified with sodium dodecylbenzenesulfonate (as a solid content) were used. did. The toner thus obtained had an average particle diameter of 6.0 μm, and when evaluated by Method 2, it was fixed at 152 to 190 ° C. or higher. Thus, comparing Example 3 using the toner containing wax and Comparative Example 1 using the toner co-aggregated at the time of aggregating the wax, the comparative example 1 has a higher fixing lower limit temperature TL, The fixing temperature range also became smaller.

Comparative Example 2 Toner particles were produced in the same manner as in Example 3 except that the resin emulsion C was changed to 100 parts (as solid content) of the resin emulsion D. The toner thus obtained is
The average particle size was 5.3 μm. When this was evaluated by Method 2, it was fixed at 160 to 190 ° C. or higher. Thus, when comparing Example 3 using the toner containing wax and Comparative Example 2 using the toner without wax, Comparative Example 2 has a higher fixing lower limit temperature TL and a wider fixing temperature range. It has become smaller.

Example 4 A resin emulsion E and toner particles were produced in the same manner as in Example 3 except that the monomers were changed as follows.

[0050]

[Table 8] (Monomers) 79 parts of styrene 21 parts of butyl acrylate 3 parts of acrylic acid 0.5 parts of trichlorobromomethane

The toner thus obtained has an average particle size of 8.1 μm.
The fixing was carried out at 48 to 190 ° C. or higher.

Comparative Example 3 A resin emulsion F and toner particles were produced in the same manner as in Comparative Example 1 except that the monomers were changed as follows.

[0053]

[Table 9] (Monomers) 79 parts of styrene 21 parts of butyl acrylate 3 parts of acrylic acid 0.5 part of trichlorobromomethane

The toner thus obtained had an average particle size of 5.9 μm.
Fixing was performed at 68 to 190 ° C. or higher. As described above, a comparison between Example 4 using the toner including the wax therein and Comparative Example 3 using the toner co-aggregated at the time of aggregating the wax shows that:
In Comparative Example 3, the fixing lower limit temperature TL was higher, and the fixing temperature width was smaller.

Comparative Example 4 Toner particles were produced in the same manner as in Example 4 except that the resin emulsion E was changed to 100 parts (as solid content) of the resin emulsion F. The toner thus obtained is
The average particle size was 4.9 μm. When this was evaluated by Method 2, it was fixed at 170 to 190 ° C. or higher. Thus, when Example 4 using the toner containing wax and Comparative Example 4 using the toner without wax are compared, Comparative Example 4
The lower fixing temperature TL was higher and the fixing temperature width was smaller.

Example 5 <Production of polymer primary particles> The following wax emulsion and demineralized water were charged into a glass reactor equipped with a stirrer, a heating / cooling device, a concentrating device, and a raw material / auxiliary charging device. The temperature was raised to 90 ° C. under a nitrogen stream.

[0057]

Table 10 Behenyl behenate emulsion (average particle size 0.42 μm) 21.3 parts (as solid content) Sodium dodecylbenzenesulfonate 0.5 part Deionized water (including water in wax emulsion) 396.9 parts

Thereafter, the following monomers, an aqueous emulsifier solution and an initiator were added, and emulsion polymerization was carried out for 5 hours.

[0059]

(Table 11) (Monomers) Styrene 72 parts Acrylic acid 28 parts Acrylic acid 3 parts Trichlorobromomethane 0.5 parts Emulsifier aqueous solution 26 parts (Initiator) 2% hydrogen peroxide aqueous solution 43.2 parts 2% ascorbic acid aqueous solution 43.2 copies

After the completion of the polymerization reaction, the mixture was cooled to obtain a milky white polymer primary particle emulsion. (Hereinafter, it is abbreviated as resin emulsion G.) The average particle size of the obtained emulsion was 144 nm, and the weight average molecular weight of the polymer was 74,000. When a cross section of the obtained emulsion was observed with a TEM, it was observed that the wax was encapsulated in the resin. Emulsion polymerization was carried out in the same manner as the resin emulsion G except that the following wax emulsion was charged into a glass reactor equipped with a stirrer, a heating / cooling device, a concentrating device, and each raw material / auxiliary charging device. H was obtained.

[0061]

[Table 12] Alkyl-modified silicone emulsion (average particle size: 0.27 µm) 21.1 parts (as solid) Deionized water (including water in wax emulsion) 392.2 parts

The resulting emulsion has an average particle size of 28.
4 nm, the weight average molecular weight of the polymer was 150,000. When a cross section of the obtained emulsion was observed with a TEM, it was observed that the wax was encapsulated in the resin. <Formation of associated particles (preparation of toner) and evaluation>

[0063]

Table 13 Resin emulsion G 60 parts (as solid content) Resin emulsion H 60 parts (as solid content) Charge control agent Bontron S-34 (10% dispersion) 0.65 part (as solid content) Phthalocyanine blue Aqueous dispersion 6.7 parts (as solid content)

The above mixture was kept at 20 ° C. for 1.5 hours while being dispersed and stirred by a disperser. Thereafter, while further stirring, the temperature was raised to 55 ° C. and maintained for 0.5 hour. In order to further increase the bonding strength of the associated particles, the temperature was raised to 95 ° C. and maintained for 5 hours. Thereafter, the obtained slurry of associated particles was cooled, filtered through a Kiriyama funnel, washed with water, and freeze-dried to obtain a toner. The toner thus obtained had an average particle size of 5.9 .mu.m, and when evaluated by Method 1, it was fixed at 115-187.degree.

Example 6 A wax emulsion was prepared except that an emulsion (average particle size: 0.27 μm) of glyceryl montanate emulsified with a nonionic surfactant was used to produce a resin emulsion (hereinafter referred to as “resin emulsion I”). In the same manner as in Example 5, a resin emulsion and toner particles were produced.
When the toner thus obtained was evaluated by the method 1, the toner was fixed at 120 to 190 ° C.

Example 7 As a wax emulsion, a polyethylene wax emulsion (Hitec E540 manufactured by Toho Chemical Co., Ltd.)
3B, average particle size 0.04 μm) in the same manner as in Example 5 except that the following monomers are used as monomers:
Resin emulsion (referred to as resin emulsion J) and toner particles were produced. When the toner thus obtained was evaluated by the method 1, it was fixed at 138 ° C.

[0067]

(Monomers) Styrene 80 parts Butyl acrylate 20 parts Acrylic acid 3 parts Trichlorobromomethane 1 part (Initiator) 2% aqueous hydrogen peroxide 43.4 parts 2% ascorbic acid aqueous solution 43.4 parts

Example 8 As a wax emulsion, a polyethylene wax emulsion (manufactured by Toho Chemical Co., Ltd., Hitec E103)
N, an average particle size of 0.03 μm) was used to produce a resin emulsion and toner particles in the same manner as in Example 7, except that a resin emulsion (referred to as resin emulsion K) was produced. When the toner thus obtained was evaluated by the method 1, it was fixed at 140 ° C.

Example 9 As a wax emulsion, an emulsion (average particle size: 0.43 μm) obtained by emulsifying a mixture of glyceride montanate and behenyl behenate with a nonionic surfactant was used, and a resin emulsion (referred to as resin emulsion L) was used. Was prepared in the same manner as in Example 7 except that a resin emulsion was prepared. When the toner thus obtained was evaluated by the method 1, the toner was fixed at 140 ° C. to 190 ° C.

The following Table summarizes the resin emulsions A to L used in the examples.

[0071]

[Table 15]

[0072]

According to the present invention, by encapsulating the wax in the polymer primary particles, a toner having a sufficient non-offset area even in the heating roller fixing method and having good OHP transparency and image glossiness can be obtained. be able to. That is, in Example 3, the fixing temperature range was 1 by incorporating wax.
In contrast, in Comparative Example 1, when the same amount of wax was co-agglomerated, the fixing temperature range was 152 to 190 ° C. or higher, and the fixing lower limit temperature was high. In the present invention, it has been found that even with the same composition, the fixing temperature varies depending on the presence of the wax. Further, in Comparative Example 2, when a toner containing no wax was synthesized and evaluated with respect to Example 3, the fixing temperature range was 160 to 190 ° C. or higher, and the minimum fixing temperature was further increased. It has become smaller. By including wax in the toner as described above, the minimum fixing temperature is lowered and the fixing temperature range is widened, but it has been found that the effect is particularly large when the wax is included.
Similarly, in the case where the monomer composition of the resin, that is, the Tg is different, in Example 4, by encapsulating the wax,
The fixing temperature range was 148 to 190 ° C or higher,
In Comparative Example 3, when the same amount of wax was co-agglomerated, the fixing temperature range was 168 to 190 ° C. or higher and the fixing lower limit temperature was higher. I confirmed the thing. Further, in Comparative Example 4, when a toner containing no wax was synthesized and evaluated with respect to Example 4, the fixing temperature width was 17%.
When the temperature is 0 to 190 ° C. or higher, the minimum fixing temperature further increases,
The fixing temperature range became smaller.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hideko Akai 1000 Kamoshita-cho, Aoba-ku, Yokohama-shi, Kanagawa Prefecture Inside Mitsubishi Chemical Research Laboratory (72) Inventor Tokuaki Takahashi 1000 Kamoshita-cho, Aoba-ku, Yokohama-shi, Kanagawa Mitsubishi F-term in Yokohama Research Laboratory, Chemical Co., Ltd. (reference) 2H005 AA06 AA15 AB03 AB06 CA13 CA14 DA01 DA06 DA10 EA05 EA07

Claims (7)

[Claims] 1. An electrostatic charge developing toner comprising a particle aggregate containing at least a polymer primary particle, wherein the polymer primary particle has a structure substantially containing wax therein. Image developing toner. 2. The electrostatic image developing toner according to claim 1, wherein the polymer primary particles are polymer particles obtained by seed polymerization using a wax emulsion as seed particles. 3. The wax emulsion having an average particle size of:
3. The structure according to claim 2, wherein the thickness is 0.01 μm to 3 μm.
3. The toner for developing an electrostatic image according to item 1. 4. The toner for developing an electrostatic image according to claim 1, wherein the polymer primary particles have an acidic polar group or a basic polar group. 5. The polymer primary particles contain the wax in an amount of from 1 part by weight to 100 parts by weight of the binder resin in the particles.
It is contained in an amount of 40 parts by weight.
5. The toner for developing an electrostatic charge image according to any one of 4. 6. A seed emulsion polymerization is carried out by sequentially adding a monomer mixture containing a monomer having an acidic polar group or a basic polar group in the presence of a wax, and then the obtained polymer primary particle dispersion and colorant primary A method for producing a toner for developing an electrostatic image, comprising mixing a dispersion liquid containing particles and aggregating the particles to form associated particles. . 7. A seed emulsion polymerization is performed by sequentially adding a monomer mixture containing a monomer having an acidic polar group or a basic polar group in the presence of a wax, and then the obtained polymer primary particle dispersion and a charge control agent are added. A method for producing a toner for developing an electrostatic image, comprising mixing a dispersion liquid containing primary particles and aggregating the particles to form associated particles.