JPH0844111A - Method for producing toner for developing electrostatic image - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide a method for producing a toner for developing an electrostatic charge image, which is excellent in blade cleaning property in an electrophotographic process and does not cause deterioration of image quality even when copying a plurality of sheets. In the method for producing a toner for developing an electrostatic image, which is obtained by polymerizing a polymerizable monomer system containing at least a low softening point substance and a colorant in a medium, the polymerizable monomer 100
5 to 30 parts by weight of a low softening point substance is contained with respect to parts by weight,
In addition, among the dynamic viscoelastic parameters obtained by the sinusoidal vibration method, the storage elastic modulus G ′ is 8.00 × 10 ³ <G ′.
It is characterized in that the particles having a substantially spherical shape are deformed by applying an external force to the particles in the range of ≦ 1.00 × 10 ⁹ dyne / cm ² .

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a toner for developing an electrostatic charge image used in electrophotography and the like, and in particular, it has an excellent blade cleaning property and does not cause deterioration of image quality even when copying a plurality of sheets. The present invention relates to a method for manufacturing a developing toner.

[0002]

2. Description of the Related Art Conventionally, as an electrophotographic method, U.S. Pat. No. 2,297,691 and JP-B-42-23910 are known.
Although many methods are known as described in JP-A-43-24748 and JP-A-43-24748, generally, a photoconductive substance is used and an electric latent image is formed on a photoreceptor by various means. After the latent image is formed, the latent image is developed with toner, and the toner image is transferred to a transfer material such as paper, if necessary, and then fixed by heating, pressure, heating pressure, solvent vapor or the like to obtain a copied image. It is a thing.

The toner remaining on the photoconductor without being transferred is cleaned by various methods, and the above steps are repeated.

Conventionally, the toner used for these purposes is generally a toner having a desired particle diameter by a fine pulverizer and a classifier after melt-mixing a coloring agent consisting of a dye and a pigment in a thermoplastic resin and uniformly dispersing them. Has been manufactured.

While this method of manufacture can produce fairly good toners, it does have certain limitations, ie, the choice of toner materials. For example, the resin colorant dispersion must be sufficiently brittle to be comminuted in an economically feasible manufacturing apparatus. However, if the resin colorant dispersion is made brittle in order to satisfy these requirements, the particle size range of the particles formed when actually pulverized at high speed tends to be wide,
In particular, a problem arises that a relatively large proportion of fine particles is contained in this. Further, such a brittle material is likely to undergo further fine pulverization or pulverization when used for developing such as a copying machine. Further, with this method, it is difficult to disperse solid fine particles such as a colorant into the resin completely and uniformly. Depending on the degree of dispersion, fog increases, image density decreases, and color mixing / transparency Care must be taken in dispersion as it causes defects. In addition, the exposure of the colorant on the fracture surface may cause fluctuations in the developing characteristics.

On the other hand, in order to overcome the problems of the toner by the pulverizing method, Japanese Patent Publication No. 36-10231 and 4
Nos. 3-10799 and 51-14895 propose a method for producing a toner by a suspension polymerization method. In the suspension polymerization method, a polymerizable monomer, a colorant,
A polymerization initiator and, if necessary, a cross-linking agent, a charge control agent, and other additives are uniformly dissolved or dispersed to form a monomer composition, and the monomer composition contains a dispersion stabilizer. The particles are dispersed in a continuous phase, for example, an aqueous phase using a suitable stirrer, and a polymerization reaction is simultaneously performed to obtain toner particles having a desired particle size.

Since this method does not include a crushing step at all, the toner does not need to be brittle, a soft material can be used, and the colorant is not exposed on the surface of the particles. It has the advantage of having excellent triboelectric charging properties. Further, since the classification process can be omitted, there are great cost reduction effects such as energy saving, time reduction, and process yield improvement.

However, since the shape of the toner obtained by this method is substantially spherical, there is a cleaning failure due to slipping of toner particles during the cleaning in the electrophotographic process, especially the blade cleaning. May occur, and the quality of the copied image may be significantly impaired.

In order to prevent this, as a method for deforming substantially spherical toner, for example, a method using a hydraulic press (Japanese Patent Laid-Open No. 2-256061) or a method using a ball mill (No. 2-256067). Gazette) or a method using an annula type wet media disperser (ibid. 2-256).
No. 068) has been proposed.

In these cases, since it is necessary to apply a relatively high energy to the toner for subjecting the toner to the deformation treatment, when the low softening point substance is not contained at all or the content thereof is low, the particles are Although it can be modified, it is difficult to apply it to a system containing a large amount of low softening point substance as in the present invention.

That is, in the modification treatment by these, the binder resin is destroyed by a rapid deformation, and in some cases,
Not only the low softening point substance leaks out and contaminates the entire system, but also sufficient copy image quality cannot be obtained.

[0012]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for producing a toner for developing an electrostatic charge image, which solves the above problems.

That is, an object of the present invention is to provide a method for producing a toner for developing an electrostatic charge image, which is excellent in blade cleaning property in an electrophotographic process and does not cause deterioration of image quality even when copying a plurality of sheets. .

[0014]

[Means and Actions for Solving the Problems]
It is achieved by the present invention described below.

That is, in the method for producing a toner for developing an electrostatic charge image obtained by polymerizing a polymerizable monomer system containing at least a low softening point substance and a colorant in a medium, 100 parts by weight of the polymerizable monomer is added. On the other hand, among the dynamic viscoelastic parameters obtained by the sinusoidal vibration method, the storage elastic modulus G ′ was 8.00 × 10 5 including 5 to 30 parts by weight of the low softening point substance.
Under the range of ³ <G ′ ≦ 1.00 × 10 ⁹ dyne / cm ² , an external force is applied to the particles so that the substantially spherical particles are deformed.

The method of applying an external force is a wet media type dispersing machine, and the specific gravity d is applied to the media.
Is 0.92 ≦ d ≦ 2.10.

The method for producing the toner of the present invention includes:
JP-B-36-10231 and JP-A-59-5385.
No. 6, JP-A-59-61842, a method of directly producing a toner by using the suspension polymerization method, or an aqueous organic solvent in which a monomer is soluble but the obtained polymer is insoluble. It is possible to produce a toner by using a dispersion polymerization method in which a toner is directly generated using a polymer or an emulsion polymerization method represented by a soap-free polymerization method in which a toner is directly polymerized in the presence of a water-soluble polar polymerization initiator. .

However, in the dispersion polymerization method, the toner obtained has an extremely sharp particle size distribution, but the selection of materials to be used is narrow and the use of organic solvents is related to the treatment of waste solvents and the flammability of the solvents. Manufacturing equipment is complicated and easy to be complicated. The emulsion polymerization method typified by soap-free polymerization is effective because the particle size distribution of the toner is relatively uniform, but when the emulsifier or the end of the initiator used is present on the surface of the toner particles, the environmental characteristics are easily deteriorated.

In the present invention, the suspension polymerization method under atmospheric pressure or under pressure is particularly preferable because a fine particle toner having a sharp particle size distribution and a particle size of 4 to 8 μm can be obtained relatively easily. The reason for this is that if the particle size distribution is uniform, the deforming treatment of the present invention can be carried out uniformly. A so-called seed polymerization method in which a monomer is further adsorbed to the polymer particles once obtained and then the polymerization is performed using a polymerization initiator can be suitably used in the present invention. In addition, a so-called salting-out association method or hetero-coagulation in which primary emulsion-polymerized particles are formed in advance with little or no use of an emulsifier, and then salted out or polymerized particles having an opposite charge in an aqueous system are added to combine The toner by the method can also be preferably used.
Further, the method for deforming the toner used in the present invention is not particularly limited, but it is preferable to use a wet media type disperser in which synthetic resin particles are used as media. The reason for this is that it is easy to obtain a balance from the viewpoint of dynamic viscoelasticity between the medium and the toner when applying impact force and shearing force.

A more preferable toner used in the present invention is a toner shape factor SF-1 measured by Luzex.
Is 110 to 135, and the low softening point substance is 5 to 30.
A low softening point substance, which is contained in an outer shell resin layer, is produced by a method of measuring a tomographic plane of a toner using a transmission electron microscope (TEM). When the storage elastic modulus G ′ obtained from the dynamic viscoelasticity measurement of the toner is in the range of 8.00 × 10 ³ <G ′ ≦ 1.00 × 10 ⁹ , it is deformed by applying a mechanical external force by the method as described above. It has been processed.

From the viewpoint of fixability, it is necessary to include a large amount of the low softening point substance in the toner, so that it is necessary to encapsulate the low softening point substance in the outer shell resin. The toner that cannot be encapsulated cannot be sufficiently pulverized unless special freeze pulverization is used in the pulverization process, and as a result, only a wide particle size distribution can be obtained, and toner fusion to the device also occurs. It's very bad. Further, in the freeze pulverization, the apparatus becomes complicated due to a measure to prevent dew condensation on the apparatus, and if the toner absorbs moisture, the workability of the toner is deteriorated, and it is necessary to add a drying step, which is a problem. As a specific method for encapsulating the low softening point substance, the polarity of the material in the aqueous medium is set to be smaller for the low softening point substance than the main monomer, and a small amount of a resin or monomer having a large polarity is used. By adding the above, it is possible to obtain a toner having a so-called core-shell structure in which a substance having a low softening point is coated with an outer shell resin. Toner particle size distribution control and particle size control are carried out by changing the type and addition amount of sparingly water-soluble inorganic salt or dispersant that acts as a protective colloid, and mechanical device conditions such as rotor peripheral speed, number of passes, stirring. The toner of the present invention can be obtained by controlling the stirring conditions such as the blade shape, the container shape, or the solid content concentration in the aqueous solution.

As a specific method for measuring the tomographic plane of the toner in the present invention, a cured product obtained by sufficiently dispersing the toner in an epoxy resin which is curable at room temperature and then curing the toner in an atmosphere at a temperature of 40 ° C. for 2 days Was stained with ruthenium tetraoxide, and optionally osmium tetraoxide, and then a thin sample was cut out using a microtome equipped with diamond teeth and the tomographic morphology of the toner was measured using a transmission electron microscope (TEM). . In the present invention, it is preferable to use the ruthenium tetroxide dyeing method in order to make a contrast between materials by utilizing a slight difference in crystallinity between the low softening point substance used and the resin constituting the outer shell. A typical example is shown in FIG. It was clearly observed that the low softening point substance was encapsulated by the outer shell resin.

The low softening point substance used in the present invention is preferably a compound having a main component maximum peak value measured according to ASTM D3418-8 of 40 to 90 ° C. When the maximum peak is less than 40 ° C., the self-aggregating force of the low softening point substance becomes weak, and as a result, the high temperature offset resistance becomes weak, which is not preferable for a full color toner. On the other hand, if the maximum peak exceeds 90 ° C., the fixing temperature becomes high, and it becomes difficult to appropriately smooth the surface of the fixed image, which is not preferable in terms of color mixing. Further, when the toner is obtained by the direct polymerization method, the temperature of the maximum peak value is high because the granulation and the polymerization are carried out in an aqueous system, so that the low softening point substance mainly precipitates during the granulation and hinders the suspension system. Therefore, it is not preferable.

In measuring the temperature of the maximum peak value of the present invention,
For example, Perkin Elmer DSC-7 is used. The melting point of indium and zinc is used to correct the temperature of the device detection unit, and the heat of fusion of indium is used to correct the amount of heat. For the sample, an aluminum pan was used and an empty pan was set as a control, and the temperature rising rate was 10 ° C./min. Measure with.

Specifically, paraffin wax, polyolefin wax, Fischer-Tropish wax,
Amide wax, higher fatty acid, ester wax and their derivatives or their graft / block compounds can be used. Particularly, in the present invention, an ester wax having one or more long-chain ester moieties having 10 or more carbon atoms represented by the following general structural formula has an effect on high temperature offset resistance without impairing transparency of OHP. preferable. The structural formulas of typical compounds of specific ester waxes preferable in the present invention are shown below as general structural formulas, general structural formulas and general structural formulas.

[0026]

Embedded image

[In the formula, a and b represent an integer of 0 to 4,
a + b is 4, R ₁ and R ₂ represent an organic group having 1 to 40 carbon atoms, and a group having a carbon number difference between R ₁ and R ₂ of 10 or more, and n and m are 0 to 0. Indicates an integer of 15, n and m
Cannot be 0 at the same time. ]

[0028]

Embedded image

[In the formula, a and b represent an integer of 0 to 4,
a + b is 4, R ₁ represents an organic group having 1 to 40 carbon atoms, n and m represent integers of 0 to 15, and n and m do not become 0 at the same time. ]

[0030]

[Chemical 3]

[In the formula, a and b represent an integer of 0 to 3,
a + b is 3 or less, and R ₁ and R ₂ have 1 to 40 carbon atoms
And an organic group having a carbon number difference of 10 or more between R ₁ and R ₂ , R ₃ is an organic group having 1 or more carbon atoms, and n and m are integers from 0 to 15. As shown, n and m are never 0 at the same time. ]

The ester wax preferably used in the present invention preferably has a hardness of 0.5 to 5.0.
The hardness of the ester wax is 20 mmφ in diameter and 5 in thickness.
It is a value obtained by measuring the Vickers hardness using, for example, a dynamic ultra-micro hardness meter (DUH-200) manufactured by Shimadzu Corporation after manufacturing a sample having a cylindrical shape of mm. The measurement conditions are
Vickers hardness is obtained by displacing 10 μm under a condition of a load rate of 9.67 mm / sec with a load of 0.5 g and holding it for 15 seconds, measuring the obtained dent shape. The hardness of the ester wax preferably used in the present invention is 0.5 to 5.0.
Indicates the value of. If the material has a hardness of less than 0.5 and has a low softening point, the pressure dependency and the process speed dependency of the fixing device become large, and the high temperature offset resistance effect is apt to be insufficiently expressed. Since the stability is poor and the release agent itself has a small self-cohesive force, the high temperature offset is likely to be insufficient in the same manner. Specific compounds include the following compounds.

[0033]

[Chemical 4]

In recent years, the need for double-sided images has been increasing, and in forming a double-sided image, the toner image on the transfer paper formed first on the front surface is also fixed on the rear surface when the image is formed on the rear surface. There is a possibility that the toner may pass through the heating part of No. 1 again, and it is necessary to more fully consider the high temperature offset resistance of the toner. Therefore, in the present invention, it is essential to add a large amount of the low softening point substance. Specifically, the low softening point substance is preferably added to the toner in an amount of 5 to 30% by weight. Addition of less than 5% by weight does not show sufficient high-temperature offset resistance, and the image on the back side tends to show an offset phenomenon when fixing a double-sided image. On the other hand, if it exceeds 30% by weight, coalescence of the toner particles is likely to occur during granulation in the production by the polymerization method, and particles having a wide particle size distribution are likely to be produced, which is not suitable for the present invention.

As the outer shell resin used in the present invention, generally used styrene- (meth) acrylic copolymers, polyester resins, epoxy resins and styrene-butadiene copolymers can be used. In the method of directly obtaining the toner by the polymerization method, those monomers are preferably used. Specifically, styrene, o (m-,
styrene-based monomers such as p-)-methylstyrene and m (p-)-ethylstyrene; methyl (meth) acrylate,
Ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, octyl (meth) acrylate, dodecyl (meth) acrylate, stearyl (meth) acrylate, behenyl (meth) acrylate, ( (Meth) acrylic acid ester-based monomers such as 2-ethylhexyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, and diethylaminoethyl (meth) acrylate; butadiene, isoprene, cyclohexene, (meth) acrylonitrile, acrylic acid An ene-based monomer such as amide is preferably used. These are alone or generally in the publication Polymer Handbook 2nd Edition III-P1.
39-192 (made by John Wiley & Sons)
The theoretical glass temperature (Tg) described in (4) is used by appropriately mixing the monomers so as to show 40 to 75 ° C. When the theoretical glass transition temperature is lower than 40 ° C, problems occur in storage stability and durability stability of the toner, while when it exceeds 75 ° C, the fixing point is increased, especially in the case of full-color toner. In the case of (3), the color mixing of the toners of respective colors is insufficient, the color reproducibility is poor, and further, the transparency of the OHP image is remarkably reduced, which is not preferable from the viewpoint of high image quality.

The molecular weight of the outer shell resin is measured by GPC (gel permeation chromatography). As a specific method for measuring GPC, the toner was previously extracted with a Soxhlet extractor in a toluene solvent for 20 hours, and then the toluene was distilled off with a rotary evaporator, and the low softening point substance was dissolved, but the outer shell resin was dissolved. Is an insoluble organic solvent (for example, chloroform), and after thorough washing, a solution soluble in THF (tetrahydrofuran) is filtered through a solvent-resistant membrane filter with a pore size of 0.3 μm to produce a sample manufactured by Waters. The column structure is A-801, 802, 80 manufactured by Showa Denko, using 150C.
3, 804, 805, 806, and 807 can be connected and a molecular weight distribution can be measured using the calibration curve of a standard polystyrene resin.
The number average molecular weight (Mn) of the obtained resin component is 5000.
~ 1,000,000, weight average molecular weight (Mw)
And the number average molecular weight (Mn) ratio (Mw / Mn) is 2 to 1
Outer shell resins exhibiting 00 are preferred for the present invention.

In the present invention, it is particularly preferable to add a polar resin in addition to the outer shell resin in order to encapsulate the low softening point substance in the outer shell resin. As the polar resin used in the present invention, a copolymer of styrene and (meth) acrylic acid, a maleic acid copolymer, a saturated polyester resin, and an epoxy resin are preferably used. It is particularly preferable that the polar resin does not contain an unsaturated group capable of reacting with the shell resin or the monomer in the molecule. In the case of containing a polar resin having an unsaturated group, a crosslinking reaction occurs with a monomer forming the outer shell resin layer, resulting in an extremely high molecular weight as a full-color toner, which is disadvantageous for color mixing of four-color toner, which is not preferable. .

As the colorant used in the present invention, carbon black, a magnetic substance, or a yellow / magenta / cyan colorant shown below, which is toned black, is used.

As the yellow colorant, condensed azo compounds, isoindolinone compounds, anthraquinone compounds,
Compounds represented by azo metal complexes, methine compounds and allylamide compounds are used. Specifically, C.I. I. Pigment Yellow 12, 13, 14, 15, 17, 6
2, 74, 83, 93, 94, 95, 109, 110,
111, 128, 129, 147, 168 and the like are preferably used.

As the magenta colorant, a condensed azo compound, a diketopyrrolopyrrole compound, an anthraquinone, a quinacridone compound, a basic dye lake compound, a naphthol compound, a benzimidazolone compound, a thioindigo compound, and a perylene compound are used. Specifically, C.I.
I. Pigment Red 2, 3, 5, 6, 7, 23, 4
8; 2, 48; 3, 48; 4, 57; 1, 81; 1, 1
44, 146, 166, 169, 177, 184, 18
5,202,206,220,221,254 are particularly preferred.

As the cyan colorant, a copper phthalocyanine compound and its derivative, an anthraquinone compound, a basic dye lake compound and the like can be used. Specifically, C.I. I.
Pigment Blue 1, 7, 15, 15: 1, 15: 2,
15: 3, 15: 4, 60, 62, 66 and the like can be used particularly preferably.

These colorants can be used alone or as a mixture, and can be used in the form of a solid solution. The colorant of the present invention is selected in terms of hue angle, saturation, lightness, weather resistance, OHP transparency, and dispersibility in the toner. The colorant is added in an amount of 1 to 20 parts by weight based on 100 parts by weight of the resin.

When a magnetic material other than carbon black is used as the black colorant, 40 to 150 parts by weight is added to 100 parts by weight of the resin, unlike other colorants.

The charge control agent used in the present invention includes
Known charge agents can be used, but a charge control agent that is colorless and has a high toner charging speed and that can stably maintain a constant charge amount is preferable. Furthermore, when the direct polymerization method is used in the present invention, a charge control agent having no polymerization inhibitory property and having no solubilized product in an aqueous system is particularly preferable. Specific compounds include metal compounds such as salicylic acid, naphthoic acid and dicarboxylic acid as negative compounds, polymer type compounds having sulfonic acid and carboxylic acid in the side chain, boron compounds, urea compounds, silicon compounds, currys arenes and the like. A quaternary ammonium salt, a high-molecular compound having a side chain of the quaternary ammonium salt, a guanidine compound, an imidazole compound or the like is preferably used as a positive system. The charge control agent is resin 10
0.5 to 10 parts by weight is preferable with respect to 0 parts by weight. However, the addition of the charge control agent is not essential in the present invention, and when the two-component developing method is used, the frictional charging with the carrier is used, and the blade is used even when the non-magnetic one-component blade coating developing method is used. By positively utilizing the triboelectric charging with the member or the sleeve member, it is not always necessary to include the charge control agent in the toner.

When the direct polymerization method is used in the present invention,
Examples of the polymerization initiator include 2,2′-azobis- (2
4-dimethylvaleronitrile), 2,2'-azobisisobutyronitrile, 1,1'-azobis (cyclohexane-1-carbonitrile), 2,2'-azobis-4-
Azo-based or diazo-based polymerization initiators such as methoxy-2,4-dimethylvaleronitrile and azobisisobutyronitrile; benzoyl peroxide, methyl ethyl ketone peroxide, diisopropyl peroxycarbonate, cumene hydroperoxide, 2,4-dichlorobenzoyl peroxide, lauroyl A peroxide type polymerization initiator such as peroxide is used. The amount of the polymerization initiator added varies depending on the desired degree of polymerization, but it is generally used in an amount of 0.5 to 20% by weight based on the monomer. Although the type of the polymerization initiator varies slightly depending on the polymerization method, it may be used alone or in combination with reference to the 10-hour half-life temperature.

It is also possible to further add and use a known crosslinking agent, chain transfer agent, polymerization inhibitor or the like in order to control the degree of polymerization.

When suspension polymerization is used in the toner production method of the present invention, the dispersant used is an inorganic compound such as tricalcium phosphate, magnesium phosphate, aluminum phosphate, zinc phosphate, calcium carbonate, Examples thereof include magnesium carbonate, calcium hydroxide, magnesium hydroxide, aluminum hydroxide, calcium metasilicate, calcium sulfate, barium sulfate, bentonite, silica, alumina, magnetic materials and ferrite. As the organic compound, polyvinyl alcohol, gelatin, methyl cellulose, methyl hydroxypropyl cellulose, ethyl cellulose, sodium salt of carboxymethyl cellulose, starch and the like can be dispersed in the aqueous phase and used. These dispersants were added in an amount of 0.
It is preferable to use 2 to 2.0 parts by weight.

As these dispersants, commercially available products may be used as they are, but in order to obtain dispersed particles having a fine and uniform particle size, the inorganic compound may be formed in a dispersion medium under high speed stirring. it can. For example, in the case of tricalcium phosphate, a dispersant suitable for the suspension polymerization method can be obtained by mixing an aqueous sodium phosphate solution and an aqueous calcium chloride solution under high speed stirring.

Further, in order to miniaturize these dispersants,
You may use together 001-0.1 weight part surfactant.
Specifically, commercially available nonionic, anionic, and cationic surfactants can be used. Examples thereof include sodium dodecylbenzene sulfate, sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate, sodium oleate, sodium laurate, and potassium stearate. , Calcium oleate and the like.

When the direct polymerization method is used in the toner manufacturing method of the present invention, the toner can be specifically manufactured by the following manufacturing method.

That is, a releasing agent, a colorant, a charge control agent, a polymerization initiator, and other additives made of a low softening point substance are added to the polymerizable monomer, and the mixture is homogenized by a homogenizer, an ultrasonic disperser or the like. The dissolved or dispersed monomer system is dispersed in an aqueous phase containing a dispersion stabilizer by a usual stirrer, homomixer, homogenizer or the like. Preferably, the stirring speed and time are adjusted so that the monomer droplets have the desired toner particle size, and granulation is performed. After that, stirring may be performed to the extent that the particle state is maintained and the particles are prevented from settling due to the action of the dispersion stabilizer. Polymerization temperature is 40
It is preferable to carry out the polymerization at a temperature of not lower than 0 ° C, generally 50 to 90 ° C. Further, the temperature may be raised in the latter half of the polymerization reaction, and in the latter half of the reaction in order to remove unreacted polymerizable monomers and by-products which may cause odor during fixing of the developer,
Alternatively, the aqueous medium may be partially distilled off after completion of the reaction. In the suspension polymerization method, it is usually preferable to use 300 to 3000 parts by weight of water as a dispersion medium with respect to 100 parts by weight of the monomer system.

For the polymerized toner obtained as described above,
Among the dynamic viscoelastic parameters obtained by the sinusoidal vibration method of the toner particles, the storage elastic modulus G ′ is 8.00 × 10 ³ <
Under the range of G ′ ≦ 1.00 × 10 ⁹ dyne / cm ² ,
It is introduced into a wet media type dispersing machine using synthetic resin particles (beads) as a medium, and a mechanical external force is applied to carry out a deforming treatment. The shaped particles are then collected by washing filtration and dried.

In the present invention, the storage modulus G ′ of the particles is
Is 8.00 × 10 ³ <G ′ ≦ 1.00 × 10 ⁹ dyne /
The reason for carrying out the modification treatment in the range of cm ² is that a balance between deformation and destruction of the particles can be obtained, and when the storage elastic modulus G ′ is 8.00 × 10 ³ dyne / cm ² or less, the particles are Cohesion between them occurred, and 1.00 × 10 ⁹ dyne / c
If it exceeds m ² , the particles are destroyed and the desired toner cannot be obtained.

Further, the specific gravity d of the synthetic resin particles used as a medium is preferably 0.92 ≦ d ≦ 2.10 from the viewpoint of impact energy and dynamic viscoelasticity. Specifically, polyethylene (PE), polymethylmethacrylate (PMMA), polytetrafluoroethylene (PT)
FE), polystyrene (PS), polystyrene-acrylonitrile copolymer (AS) and the like.

Furthermore, in the case of a two-component developer, a carrier is added to and mixed with the obtained toner particles to obtain a developer.

The storage modulus of the particles is determined by Rheometer R
It was determined by temperature dispersion measurement with DA-II (manufactured by Rheometric Co.).

The measurement conditions are as follows: measurement frequency 1 Hz measurement geometry parallel plate (diameter 8 m
m) Measurement temperature range: 30 to 95 ° C, heating rate: 2 ° C / min.

The value of SF-1 indicating the shape factor was used as an index showing the degree of irregularity of the particles.

In calculating SF-1, FE-SE
Using M (S-800: Hitachi, Ltd.), 1 toner image
00 pieces were randomly sampled, and the image information was introduced into the image analyzer Luzex3 (manufactured by Nireco) via the interface, analyzed, and

[0060]

[Equation 1] I asked more.

The case of SF-1> 110 was defined as anomalous.

[0062]

EXAMPLES The present invention will be specifically described by the following examples.

Example 1 The cyan toner used in this example was prepared as follows. 710 parts by weight of ion-exchanged water and 450 parts by weight of 0.1 mol / liter-Na ₃ PO ₄ aqueous solution were added to a 2-liter four-necked flask equipped with a high-speed stirring device TK-Homomixer, and the rotation speed was set to 12,000. It was prepared and heated to 65 ° C. 1.0 mol / liter-CaCl ₂
68 parts by weight of the aqueous solution was gradually added to prepare a dispersion medium system containing a minute water-insoluble dispersant Ca ₃ (PO ₄ ) ₂ . On the other hand, the dispersoid system is

Styrene monomer 165 parts by weight n-butyl acrylate monomer 35 parts by weight C.I. I. Pigment Blue 15: 3 13 parts by weight Saturated polyester 9 parts by weight (terephthalic acid-propylene oxide modified bisphenol A acid value 13, peak molecular weight 7000) Metal salicylate compound 2 parts by weight Compound (1) 60 parts by weight (peak temperature in DSC 59.4 ° C)

After the above mixture was dispersed for 2 hours using an attritor, 10 parts by weight of 2,2'-azobis (2,4-dimethylvaleronitrile) as a polymerization initiator was added to the dispersion medium. Input 1 while maintaining the rotation speed
Granulated for 3 minutes. After that, the stirrer was changed from the high-speed stirrer to the propeller stirrer, the internal temperature was raised to 80 ° C., and the polymerization was continued at 50 ° C. for 10 hours. After completion of the polymerization, a part of the slurry was sampled, further washed and dried, and the physical properties of the obtained cyan toner were measured. The weight average particle diameter of the cyan toner measured using a Coulter counter was 6 μm, the number variation coefficient was 28%, and SF-1 was 105. As a result of TEM observation, it was shown that the compound (1) which is a low softening point substance was covered with the outer shell resin.

Further, the cyan toner was compressed under pressure at a pressure of 400 kg / cm ² for 5 minutes at room temperature using a pressure molding machine to mold tablets having a diameter of 8 mm and a thickness of 3.0 mm.

The above-mentioned rheometer (PDAII:
Rheometric) was used to measure the storage elastic modulus at the same temperature as the slurry.

At this time, the storage elastic modulus G'obtained by the sinusoidal vibration method of the polymer particles is 5.95 × 10 ⁵ dyne /
cm ² .

The slurry was kept at 80 ° C. and introduced into a wet media type dispersing machine (Apex Mill: Kotobuki Giken Co., Ltd.) in order to give a mechanical impact force to the PMMA resin beads (diameter 0.75 mm) Specific gravity 1.19)
Was used for 75 seconds at a filling rate of 70% by volume at 750 rpm. After that, the dispersion stabilizer in the toner slurry was removed by washing with 0.5 N hydrochloric acid and washing with water, and the toner was obtained by pressure filtration and drying.

When the shape factor SF-1 was determined in order to evaluate the degree of deformation of this toner, it was found that the shape factor SF-1 was 121 and the deformation treatment was performed.

Further, a durability test was conducted using a full-color copying machine (modified CLC500, manufactured by Canon Inc.) for the purpose of investigating the effect of improving the durability of copy quality and blade cleaning property. Even in continuous copying, vertical streaks due to deterioration of copy quality and defective blade cleaning were not observed, and good durability,
Improved cleaning properties were obtained.

Example 2 Slurry temperature was 40 ° C. and storage modulus G ′ of the toner particles obtained by the sinusoidal vibration method was 8.98 × 10 ⁸ dy.
Except for setting ne / cm ² , the same operation as in Example 1 was performed.

At this time, SF-1 was 119, and good results were obtained in terms of copy image quality durability and blade cleaning property.

Example 3 The same operation as in Example 1 was carried out except that 1.0 mmφ polyethylene (specific gravity 0.92) was used for the resin media beads. SF-1 at this time was 131, and good deforming was obtained. Further, the copy image durability and the blade cleaning property were also good.

Example 4 The same operation as in Example 1 was carried out except that 3.0 mmφ polytetrafluoroethylene was used for the resin media beads. At this time, SF-1 was 133, and good deforming was obtained. Further, the copy image durability and the blade cleaning property were also good.

Example 5 Except that the compound (2) was used in place of the compound (1),
The completely same operation as in Example 1 was performed.

At this time, the storage elastic modulus of the toner particles obtained by the sinusoidal vibration method is 8.82 × 10 ⁸ dyne.
/ Cm ² , and the shape factor SF-1 was 124, which was subjected to the deforming treatment. Further, the durability of the copy quality and the blade cleaning property were good.

Example 6 The same operation as in Example 1 was carried out except that the compound (2) was used in place of the compound (1) and the polyethylene beads (PE) were used as the resin medium.

At this time, the storage elastic modulus of the toner particles obtained by the sinusoidal vibration method is 8.82 × 10 ⁸ dyne /
cm ² and a shape factor SF-1 of 119, which was modified. Also, the durability of the copy quality and the blade cleaning property were good.

Example 7 The same operation as in Example 1 was carried out except that the compound (2) was used in place of the compound (1) and PTFE was used as the resin medium.

The storage elastic modulus G'obtained by the sinusoidal vibration method of the toner particles at this time is 8.82 × 10 ⁸ dyn.
It was e / cm ² and SF-1 was 127, which was sufficiently modified. Also, the image quality durability of this toner,
The blade cleaning property was good.

Example 8 Except that the compound (3) was used instead of the compound (1),
The completely same operation as in Example 1 was performed. The storage modulus G ′ of the toner particles at this time is 7.20 × 10 ⁶ dyne /
a cm ^2, SF-1 had been treated favorably profiled and 121. Further, the image quality durability and blade cleaning property of this toner were good.

Example 9 The same operation as in Example 1 was carried out except that the slurry temperature was 40 ° C. and the compound (4) was used instead of the compound (1). At this time, the storage modulus G ′ of the toner particles is 1.00 × 10 ⁹ dyne / cm ² , and SF-1 is 1
11 was sufficiently modified. Further, the image quality durability and blade cleaning property of this toner were good.

Example 10 The same operation as in Example 1 was carried out except that the slurry temperature was 40 ° C. and the addition amount of the compound (1) was 10 parts by weight. The storage modulus G ′ of the toner particles at this time is 1.0.
The shape factor was 4 × 10 ⁶ dyne / cm ² , and the shape factor SF-1 was 118, indicating that the material was sufficiently deformed. Further, the image quality durability and blade cleaning property of this toner were good.

Example 11 The same operation as in Example 1 was carried out except that the slurry temperature was 90 ° C., the addition amount of the compound (1) was 10 parts by weight, and PE was used as the resin medium. At this time, the storage modulus G ′ of the toner particles was 8.72 × 10 ³ dyne / cm ² , and the shape factor SF-1 was 131, which was sufficiently modified. Further, the image quality durability and blade cleaning property of this toner were good.

Example 12 The same operation as in Example 1 was carried out except that the slurry temperature was 90 ° C., the addition amount of the compound (1) was 10 parts by weight, and PTFE was used as the resin medium. The storage modulus G ′ of the toner particles at this time is 8.72 × 10 ³ dyne / c.
m ² and the shape factor SF-1 was 134, which was sufficiently modified. Further, the image quality durability and blade cleaning property of this toner were good.

Comparative Example 1 The same operation as in Example 1 was carried out except that the toner obtained by suspension polymerization and having no external force applied was used. The shape factor SF-1 of the toner was 105. Further, in the evaluation of blade cleaning, a defect occurred in durability of only 10 sheets.

Comparative Example 2 Except that the slurry temperature was 30 ° C. and the storage elastic modulus of the polymerized toner particles obtained by the sinusoidal vibration method was 1.24 × 10 ⁹ dyne / cm ² . The completely same operation as in Example 1 was performed. Shape factor SF- at this time
No. 1 was deformed to 139, but as a result of observation with an optical microscope at 200 times, many crushed polymerized toner particles were observed. Also, in the evaluation of copy image durability, only 1
Image whitening occurred at the end of 00 sheets.

Comparative Example 3 The storage elastic modulus of polymerized toner particles obtained by the sinusoidal vibration method at a slurry temperature of 95 ° C. was 1.49 × 10 ³ dyne.
The same operation as in Example 1 was performed except that / cm ² was used. In this case, the desired toner could not be obtained because the polymerized toner particles were aggregated and agglomerated during the deforming treatment to form a lump.

Comparative Example 4 The same operation as in Example 1 was carried out except that the addition amount of the compound (1) was 10 parts by weight and the slurry temperature was 30 ° C. Cohesion due to crushing of toner particles occurred during the deforming treatment, and the desired toner could not be obtained. The storage modulus G ′ of the toner particles at this time is 3.22 × 10 ⁹ dyn
It was e / cm ² .

Comparative Example 5 The slurry temperature was 30 ° C., the compound (2) was used in place of the compound (1), and PE having a diameter of 1.00 mm was used as the medium.
Except for using particles, the same operation as in Example 1 was performed. At this time, the storage modulus G ′ of the toner particles is 2.1.
It was 4 × 10 ⁹ dyne / cm ² and the shape factor SF-1 was 106, which means that it was not deformed. Regarding the blade cleaning property, cleaning failure occurred after only 10 sheets.

Comparative Example 6 The slurry temperature was 95 ° C., the compound (3) was used in place of the compound (1), and the medium was PT having a diameter of 3.00 mm.
The same operation as in Example 1 was performed except that FE was used. In this case, the toners were fused to each other during the deforming treatment, and the desired toner could not be obtained. The storage elastic modulus G ′ at this time was 1.99 × 10 ³ dyne / cm ² .

Comparative Example 7 The same operation as in Example 1 was carried out except that the slurry temperature was 30 ° C., the compound (4) was used instead of the compound (1), and the addition amount was 10 parts by weight. . During the deforming treatment, coalescence due to crushing of toner particles occurred, and a desired toner could not be obtained. The storage elastic modulus at this time is 5.1.
It was 0 × 10 ⁹ dyne / cm ² .

[0094]

[Table 1]

[0095]

As described above, according to the present invention, even a toner containing a large amount of a substance having a low softening point can be appropriately deformed, and the blade cleaning property and the deterioration of image quality even when a plurality of sheets are copied. It is possible to obtain an excellent electrostatic charge image developing toner that does not occur.

[Brief description of drawings]

FIG. 1 is a schematic view of a toner layer in which a substance having a low softening point is encapsulated by an outer shell resin.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Koji Inaba 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc.

Claims (4)

[Claims] 1. A process for producing a toner for developing an electrostatic charge image, which is obtained by polymerizing a polymerizable monomer system containing at least a low softening point substance and a colorant in a medium, wherein the polymerizable monomer 1 is used.
5 to 30 parts by weight of the low softening point substance is included in the amount of 00 parts by weight, and among the dynamic viscoelastic parameters obtained by the sinusoidal vibration method, the storage elastic modulus G ′ is 8.00 × 10 ³ <
A toner for developing an electrostatic charge image, characterized in that the particles having a substantially spherical shape are deformed by applying an external force thereto under the range of G ′ ≦ 1.00 × 10 ⁹ dyne / cm ^2. Manufacturing method. 2. A method for applying an external force is a wet media type disperser, and synthetic resin particles having a specific gravity d of 0.92 ≦ d ≦ 2.10 are used for the media. The method for producing a toner for developing an electrostatic charge image according to claim 1. 3. The toner before applying an external force is manufactured by a direct polymerization method in which a low softening point substance is encapsulated in an outer shell resin layer by a method of measuring a tomographic plane of the toner using a transmission electron microscope (TEM). The method for producing a toner for developing an electrostatic charge image according to claim 1, wherein the toner is a generated toner. 4. The method for producing an electrostatic charge image developing toner according to claim 1, wherein the low softening point substance is an ester wax having at least one long-chain ester moiety having 10 or more carbon atoms.