JPH05197193A - Toner for electrostatic charge image development - Google Patents

Abstract

PURPOSE:To provide a toner for electrostatic charge image development having excellent blocking resistance, excellent low-temperature fixing property and mold releasing property, and stably high developing property even in the high- temperature and high-humidity environment. CONSTITUTION:Toner grains of a toner for electrostatic charge image development having the toner grains obtained by suspension polymerization contain at least two types of constituents: high-softening point resin (A) and low- softening point resin (B), and have a structure divided into the phase A mainly made of the high-softening point resin (A) and the phase B mainly made of the low-softening point resin (B). No phase B exists near the surface to the depth 0.15 times the toner grain size from the surface of the toner grains, and the toner grains contain 1,000ppm or below of an organic solvent, a polymerized monomer, or their mixture. The relation of 1.00< R/r<=1.20 preferably exists between the maximum inscribed circle having a radius (r) and the minimum circumscribed circle having a radius R for the projection plane of the toner grains. The relation of 1.01<L/1<2.00 is preferably satisfied between the peripheral length L of the projection plane of the toner grains and the circumference (1) of the inscribed circle.

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 for developing an electrostatic charge image and thermally fixing it in an image forming method such as electrophotography.

[0002]

2. Description of the Related Art In order to visualize an electrostatic or electrostatic latent image on a recording medium, electrostatically sensitive or magnetically sensitive fine particles called toner are adsorbed on the latent image. There is an image forming method for forming a visible image.

As a typical example of the electrophotographic method, many methods are known as described in US Pat. No. 2,297,691. In this electrophotographic method, generally, a photoconductive substance is used to form an electric latent image on a photoconductor by various means, and then the latent image is developed with a toner to form a toner image. Then, if necessary, the toner image is transferred to a transfer material such as paper, and then the toner image is fixed on the transfer material by using heat, pressure and / or solvent vapor to obtain a copy. At present, a fixing method using heat is predominant in terms of fixing strength of a copy, ease of handling a transfer, and comfort of work. As a heat fixing method, there is a method using radiant heat such as a heat chamber method, but the so-called heat roller fixing method of pressing a heated roll-shaped heating member against a toner image to fix it has high thermal efficiency and high speed compatibility. It is used in most machines because of its high safety. However,
Even though it is highly efficient, the energy used for heat melting occupies a considerable amount in the copier,
Further, the so-called offset phenomenon, in which the toner adheres to the heat roll to directly contact the melted toner image and stains the subsequent image, and the so-called wrap-around phenomenon in which the toner to be fused around the heat roll is inevitable. There is. In order to reduce the energy required for melting the toner, increase the amount of components that melt at low temperature and reduce the adhesion of the toner to the heat roll. The presence of waxes or oils that fluidize quickly and have a small cohesive energy is effective, but at the same time, these substances have the drawback that the fluidity of the toner is lowered and the developability is significantly lowered.

Conventionally, toners used for these purposes are generally prepared by mixing and melting a coloring material consisting of a dye and / or a pigment or a magnetic material in a thermoplastic resin to uniformly disperse the coloring material, and then finely pulverizing it. By classification, it has been manufactured as a toner having a desired particle size. This method is relatively stable as a technology, and it is possible to manage each material and each process relatively easily.However, since the contents are exposed at the fracture surface, the above-mentioned components for lowering the melting point and It was not possible to contain enough components for mold release to be effective. Further, in this method, it is necessary to melt the material together with the binder resin in order to mix and immobilize the material, and to cool the melt and then mechanically pulverize it. Since the particles are pulverized, the particle size tends to be widened, and it is necessary to adjust the particle size distribution to a desired particle size distribution in a subsequent classification step, and there is a drawback that the product yield cannot be increased. To solve these problems, a toner manufacturing method using a so-called polymerization method has been proposed as a new manufacturing method.

For example, Japanese Patent Publication No. 36-10231, Japanese Patent Publication No. 47-51830, and Japanese Patent Publication No. 51-14895.
JP-A-53-17735, JP-A-53-
17736 and JP-A-53-17737, there is a so-called suspension polymerization method for producing a toner.
In the suspension polymerization method, inclusion in a toner such as a binder resin, a colorant such as a dye or a pigment, a magnetic substance, carbon black, a charge control agent, a release agent such as wax and silicone oil is required. A substance that is uniformly dissolved in the polymerizable monomer together with a polymerization initiator or a dispersant, if necessary.
Alternatively, it is dispersed to form a polymerizable composition, and the polymerizable composition is used to form fine particles in an aqueous continuous phase containing a dispersion stabilizer using a disperser, and then a polymerization reaction is caused to solidify, at the end of polymerization. This is to obtain toner particles having a desired particle diameter at once.

According to this method, since there is no crushing step,
In some cases, not only the melting and crushing steps but also the subsequent classification step can be omitted without the problems related to the crushing method described above, such as saving energy, shortening the time, and improving the process yield. Great cost reduction effect.

[0007]

The present inventors have heretofore considered that in suspension polymerization in an aqueous medium, the polar component is concentrated near the interface and the nonpolar component is concentrated in the center, and We have developed a polymerized toner that contains a large amount of silicone oil, waxes, or low molecular weight components with a molecular weight of 3000 or less that cannot be produced or stored by a toner production method that relies on kneading and pulverization, and that can fix at low temperature and can be fixed at the time of fixing. A toner was obtained which does not require the application of a release agent to the toner.

In the suspension polymerization method, in the case of a styrene-acrylic vinyl polymerizable monomer, the amount of the polymerization initiator is 0.5 to 2
By setting the polymerization temperature to 0% by weight and setting the half-life of the initiator to 0.5 to 30 hours, a toner composition usable as a heat fixing toner can be obtained.

With this setting, if the polymerization conversion rate is 90% or more, the toner particles will not coalesce into a dough-like shape even if stirring is stopped. For example, when the polymerization conversion rate reaches 97 to 98%. If taken out and dried, it can be used as a toner without any particular problems.

However, when a large amount of low-temperature melting wax is contained in this polymerized toner system, a high-quality image can be obtained without any problem under normal environment, but when left in a high-temperature environment, blocking resistance is improved. There was a phenomenon in which the developing property was lowered and the developing property was remarkably lowered.

US Pat. No. 4,971,879 describes a toner resin obtained by suspension polymerization in which the residual monomer content in the resin is 200 ppm or less.

However, US Pat. No. 4,971,879
In the specification, it is described that the amount of residual monomer in the resin for toner is reduced, and the technique for reducing the residual monomer in the toner obtained by suspension polymerization containing a large amount of the wax is essentially Is different.

Further, focusing on the shape of the toner obtained by suspension polymerization, the toner has a spherical shape, and it has been considered that the shape of the toner is suitable for high image quality. However, spherical toner tends to deteriorate its characteristics when various external additives are added, and thus cannot be a toner having excellent durability.Generally, spherical toner has a strong adhesive force to a photoreceptor. It was also confirmed that the image deterioration caused by the transfer failure and the cleaning failure after the transfer process are likely to occur.

An object of the present invention is to provide an electrostatic charge image developing toner that solves the above problems.

An object of the present invention is to provide a toner for developing an electrostatic image which is excellent in blocking resistance even in a high temperature and high humidity environment.

An object of the present invention is to provide a toner for developing an electrostatic charge image, which is fixed at a low temperature, has excellent releasability, and exhibits stable and high developability.

An object of the present invention is to provide a toner for developing an electrostatic charge image which can obtain a high image density.

It is an object of the present invention to provide a toner for developing an electrostatic charge image, which does not change its performance over a long period of use.

[0019]

The object of the present invention is achieved by the following constitutions.

In the toner for developing an electrostatic image having the toner particles obtained by the suspension polymerization method, the toner particles are
It contains at least two components of a high softening point resin (A) and a low softening point substance (B), and comprises an A phase mainly composed of the high softening point resin (A) and the low softening point substance. It has a structure separated into the B phase as a main component, and in the vicinity of the surface from the toner particle surface to a depth of 0.15 times the toner particle diameter,
The toner for developing an electrostatic charge image is characterized in that the B phase does not exist and the toner particles contain 1,000 ppm or less of an organic solvent, a polymerizable monomer or a mixture thereof.

The present invention will be described in detail below.

As shown in FIG. 1, the toner of the present invention has an internal structure having a surface layer portion (A phase) and a central portion (B phase), and is divided into two phases by a clear interface. By taking such a capsule-like structure and functionally separating the surface layer portion and the central portion, it becomes possible to design a toner that cannot be achieved with the conventional toner. Specifically, a high softening point resin is used for the surface layer to form a toner that is resistant to blocking and stirring by the developing device, and a low softening point substance is used for the central part, which is excellent in fixing property at the same time. It can be toner.
Further, a release material having a low melting point is contained in the central portion and extruded by pressurizing at the time of fixing, whereby the offset resistance can be remarkably improved. further,
The charge controllability may be imparted only to the surface layer portion.

In contrast to the so-called pseudo capsule proposed in Japanese Examined Patent Publication No. 1-53786, a solid surface layer is formed in the present invention. Part material does not seep into the surface layer. Therefore, the phenomenon that the low softening point substance in the central portion contaminates the carrier or the developing sleeve is remarkably improved. In particular, it is superior to the pseudo capsule when a large amount of the substance to be contained in the central portion is included.

Further, the toner of the present invention comprises a low softening point substance (B) such as a low molecular weight component and a non-polar component in the polymer, which is encapsulated in the center of the toner particles by a suspension polymerization method. However, when the toner is agitated by this suspension polymerization method, the viscosity of the polymerizable monomer system increases as the polymerization reaction proceeds, and it becomes difficult for the radical species and the polymerizable monomer to move, and Unreacted polymerizable monomer is likely to remain. In the case of a toner manufactured by an ordinary pulverization method, residual polymerizable monomer can be driven out by the heat applied during the manufacturing of the resin for the toner or during the melt kneading, but it is manufactured by the suspension polymerization method of directly manufacturing the toner. In the case of the above toner, it is not possible to apply high heat, so a large amount of the polymerizable monomer remains in the toner particles as compared with the usual pulverization toner. If the toner obtained by this suspension polymerization method is left at a high temperature in the absence of water, unreacted polymerizable monomer gradually evaporates from the surface, and low molecular weight components and non-polar components in the center It is considered that the developability of the toner is deteriorated by transporting and leaving a low softening point substance such as a component on the surface portion. In the toner, a trace amount of a volatile organic solvent component is present in addition to the polymerizable monomer, and the content of all solvent components including these is 1,0 at the time of producing the suspension polymerization toner.
By controlling the content to be not more than 00 ppm, it is possible to obtain a toner which does not deteriorate due to deterioration even when it is left at a high temperature while encapsulating a large amount of the low softening point substance.

Further, the toner of the present invention preferably has irregularities on its surface. An example of the surface shape is shown in FIG. It has been clarified that the contact points between toner particles are reduced by having such unevenness on the surface, the blocking resistance is improved, and the long-term stability of the blocking resistance is also improved. Generally, by adding a fluidity-imparting agent to the toner, it becomes a spacer,
Blocking resistance is improved. However, when various additives such as a fluidity-imparting agent are used for a spherical toner by ordinary suspension polymerization, the additives adhere to the surface of toner particles due to stress such as stirring, and thus the function of the additive is reduced. The phenomenon of being disturbed occurs. On the other hand, when the toner particles have irregularities on the surface, the irregularities on the surface of the toner particles prevent the additive from deteriorating, so that it is considered that good blocking resistance can be maintained for a long period of time. Further, the unevenness of the toner surface also improves the cleaning property.

Since the toner produced by the suspension polymerization method of the present invention is substantially spherical, a high-quality image can be obtained, and fine pulverization due to stirring of the developing device does not easily occur. No scattering occurs.

In the present invention, at least two components, a high softening point resin A and a low softening point substance B, preferably A: B = 5.
It is contained in the range of 0:50 to 95: 5 and has a structure in which a phase mainly composed of A and a phase mainly composed of B are separated. The phase mainly composed of A is the surface layer part, and the phase mainly composed of B is present in the central part.

The preferred range of the resin A is the molecular weight distribution by GPC, and the weight average molecular weight Mw is 5,000-.
It is preferably 200,000, and the outflow starting point by the flow tester is preferably 65 to 100 ° C. Resin A is
Any resin can be used as long as it is a resin obtained by suspension polymerization, but it may have a functional group that can serve as a charging site or a functional group that enhances adhesiveness to paper.

The polymerizable monomers usable in the suspension polymerization include styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, p-methoxystyrene,
Styrenic monomers such as p-ethylstyrene; methyl acrylate, ethyl acrylate, n-butyl acrylate,
Acrylic esters such as isobutyl acrylate, n-propyl acrylate, n-octyl acrylate, dodecyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, 2-chloroethyl acrylate, phenyl acrylate; methyl methacrylate, Ethyl methacrylate, n-propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, phenyl methacrylate, dimethylaminoethyl methacrylate, Methacrylic acid esters such as diethylaminoethyl methacrylate; acrylonitrile; methacrylonitrile; acrylamide.

These monomers may be used alone or in combination. Among the above-mentioned monomers, it is preferable to use the styrene-based monomer alone or in combination with other monomers, from the viewpoint of developing characteristics and durability of the toner.

The preferred range of the component B used in the present invention is that the weight average molecular weight Mw is 300 to 10,000 in terms of molecular weight distribution by GPC, and the melting point is 3
The temperature is preferably 0 to 130 ° C, more preferably 60 to 100 ° C. If the melting point is lower than 30 ° C,
When the toner is fixed, a low temperature offset is promoted to exert an adverse effect, and if the melting point is higher than 130 ° C., the resin B is solidified during toner production and the granulation property is deteriorated.

When a wax is used as the component B, the effect of the present invention is further exerted. Examples of the waxes used in the present invention include paraffin waxes, polyolefin waxes and modified products thereof such as oxides and graft-treated waxes, higher fatty acids, metal salts thereof, and amide waxes.

The ratio of resin A to component B is A: B
= 50: 50 to 95: 5, and more preferably A: B = 70: 30 to 90:10. A:
If the amount of component B is more than B = 50: 50, the capsule structure may not be maintained, and if the amount of component B is less than A: B = 95: 5, the action and effect of component B may not be sufficiently exhibited.

In the present invention, there is no phase mainly composed of B in the vicinity of the surface from the surface of the toner particles to a depth of 0.15 times the particle diameter of the toner. That is, the surface layer is conceptually 0.15 times thicker than the toner particles, but even if there is a crack and there is no 0.15 times thicker portion, the B If there is no phase based on, it is included in the scope of the present invention. If a phase mainly composed of B is present in the vicinity of the surface from the surface of the toner particles to a depth of 0.15 times the particle diameter of the toner, the capsule structure becomes unstable and, for example, blocking deteriorates.

In the present invention, the cross section of the toner particles is observed by a transmission electron microscope by a dyeing ultra-thin section method, and a B phase mainly containing B is present in the vicinity of the surface to a depth of 0.15 times the toner particle diameter. Confirm whether to do.

As described above, the toner particles in the present invention are preferably substantially spherical, and have a maximum inscribed circle of radius r and a minimum circumscribed circle of radius R with respect to the projection plane of the toner particles. It is preferable that there is a relationship of 1.00 <R / r ≦ 1.20. When R / r increases, the shape is away from the spherical shape, and when R / r exceeds 1.20, the characteristics of the spherical toner disappear. The weight average particle diameter of these spherical toner particles is preferably 2 to 20 μm, more preferably 3 to 12 μm, and further preferably 4 to 10 μm.
μm.

Further, in the present invention, it is preferable that the peripheral length L of the projection surface of the toner particles and the circumference 1 of the inscribed circle satisfy the relationship of 1.01 <L / 1 <2.00. .. Perimeter length L of toner particles
Is less than 1.01 × 1, almost no unevenness is present, and if greater than 2.00 × 1, many fine minute unevennesses or unevenness with a large drop exists. When the peripheral length L of the toner particles is smaller than 1.01 × 1, the unevenness is too small to exert the effect, and when the peripheral length L of the toner particles is smaller than 2.00 × 1, it is substantially Since the shape of the developing device approaches an irregular shape, it is difficult to obtain high image quality, and further, fine powder in the developing device is likely to occur.

The projection surface of toner particles in the present invention means
By an electron microscope, it means an image obtained by focusing on the contour of a particle at a magnification of at least 2,000 times or more, preferably 5,000 times, and further using a Luzex 5000,
As shown in FIG. 2A, the radii r and R of the inscribed circle and the circumscribed circle were obtained, and further, the peripheral length L was obtained as shown in FIG. 2B.

Such a toner image, at least 50
It is preferable that R, r, and L are measured for individual pieces, preferably 100 or more pieces, and the average value thereof is included in the claims.

The above-mentioned surface modification is carried out by dissolving a polar resin which is soluble in the monomer for forming the resin A mainly constituting the surface phase in the monomer and then carrying out an ordinary granulation-polymerization step. Can be achieved.

The polar resin which can be used is (1) a cation such as a polymer of a nitrogen-containing monomer such as dimethylaminoethyl methacrylate or diethylaminoethyl methacrylate, or a copolymer thereof with styrene or an unsaturated carboxylic acid ester. Polymer, (2) Nitrile-based monomers such as acrylonitrile; Halogen-containing monomers such as vinyl chloride; Unsaturated carboxylic acids such as acrylic acid and methacrylic acid; Unsaturated dibasic acids; Unsaturated dibasic Examples thereof include anionic polymers such as acid anhydrides; polymers of nitro monomers or copolymers thereof with styrene monomers, but are not particularly limited.

Among these polar resins, the weight average molecular weight / number average molecular weight (Mw /
Mn) is preferably 1.2 to 10, more preferably 1.
5 to 5 is good. When such a resin is added to the monomer and granulated or polymerized, the phase separation between the phase mainly containing the resin A (A phase) and the phase mainly containing the component B (B phase) is promoted.
That is, the interface between the A phase and the B phase becomes clear, and the concentration of the component B contained in the A phase is significantly reduced. As a result, the capsule structure of the toner itself becomes more prominent, and it is possible to achieve both improved blocking resistance and improved fixability.

Further, the above tendency becomes more remarkable as the acid value of the polar resin is higher, and when the acid value is preferably 5 or more, more preferably 20 or more, the phase separation is promoted. In addition, those having a high acid value are likely to be unevenly distributed in the vicinity of the surface of the toner particles even in the A phase, and as a result, it becomes possible to obtain an uneven toner having a depressed surface that greatly affects the shape of the toner surface. Although the details are unknown, the resin with a high acid value gathers in the vicinity of the surface of the toner particles in the initial stages of granulation and polymerization,
As the polymerization reaction of the monomer progresses, some polar resins gather as a kind of aggregate near the surface. It was presumed that, when the volumetric shrinkage due to the polymerization of the monomer eventually occurred, the degree of the shrinkage greatly varied depending on the uneven distribution of the polar resin, and eventually the atypical toner particles had a depressed surface. Such an effect is less likely to occur when the acid value is less than 5.

On the contrary, if the acid value is too high,
The surface condition of the toner particles is greatly disturbed and the granulation property is significantly reduced, which is not preferable, and the acid value is preferably 5 to 5.
It is preferably 100, more preferably 20-80.
Even if the acid value is 20 to 80, if Mw / Mn is 10 or more, it is difficult to uniformly disperse in the monomer, and it tends to be difficult to obtain a toner having a desired particle size distribution. Naturally, it is difficult to apply a polar resin having an extremely high Mw that does not uniformly dissolve in the monomer to the suspension polymerization method toner used in the present invention. Even if polymerization is performed using a polar monomer instead of the polar resin, the amorphism does not occur at all, and if the polymerization is performed using a larger amount of the polar monomer, the granulation property tends to be significantly reduced. Therefore, it is necessary to use a polar resin having a high acid value in order to obtain the toner having the uneven shape on the surface layer as described above.

The polymerization initiator used in the present invention has a half-life of 0.5 to 30 hours during the polymerization reaction, and the polymerization reaction is carried out at an addition amount of 0.5 to 20% by weight of the polymerizable monomer. Thus, a polymer having a maximum in the molecular weight of 10,000 to 100,000 can be obtained, and the desired strength and proper melting characteristics of the toner can be provided. Examples of the polymerization initiator include 2,2′-azobis- (2,4-dimethylvaleronitrile) and 2,2′-
Azo such as azobisisobutyronitrile, 1,1'-azobis (cyclohexane-1-carbonitrile), 2,2'-azobis-4-methoxy-2,4-dimethylvaleronitrile, azobisisobutyronitrile -Based or diazo-based polymerization initiators; benzoyl peroxide, methyl ethyl ketone peroxide, diisopropyl peroxycarbonate, cumene hydroperoxide, 2,4-
Examples thereof include peroxide type polymerization initiators such as dichlorobenzoyl peroxide and lauroyl peroxide.

In the present invention, it is preferable to add a charge control agent to the toner material in order to control the chargeability of the toner. As these charge control agents, among known ones, those having almost no polymerization inhibitory property and water phase transfer property are used. For example, as a positive charge control agent, a nigrosine dye, a triphenylmethane dye, a quaternary ammonium salt, an amine is used. Examples of the negative charge control agent include metal-containing salicylic acid compounds, metal-containing monoazo dye compounds, styrene-acrylic acid copolymers, styrene-methacrylic acid copolymers, and the like.

As the colorant used in the present invention, known colorants can be used, for example, carbon black, iron black,
C. I. Direct Red 1, C.I. I. Direct Red 4, C.I. I. Acid Red 1, C.I. I. Basic Red 1, C.I. I. Mordant Red 30, C.I. I. Direct Blue 1, C.I. I. Direct Blue 2, C.I.
I. Acid Blue 9, C.I. I. Acid Blue 15,
C. I. Pigment Blue 15, C.I. I. Basic Blue 3, C.I. I. Basic Blue 5, C.I. I. Mordant Blue 7, C.I. I. Direct Green 6, C.I.
I. Basic Green 4, C.I. I. Dyes such as Basic Green 6, Yellow Lead, Cadmium Yellow, Mineral Fast Yellow, Navel Yellow, Naphthol Yellow S, Hansa Yellow G, Permanent Yellow NC
G, tartrazine lake, molybdenum orange, permanent orange GTR, benzidine orange G, cadmium red, C.I. I. Pigment Red 122, Permanent Red 4R, Watching Red Calcium Salt,
Brilliant Carmine 3B, Fast Violet B,
Pigments such as methyl violet lake, dark blue, cobalt blue, alkali blue lake, Victoria blue lake, quinacridone, rhodamine lake, phthalocyanine blue, fast sky blue, pigment green B, malachite green lake, and final yellow green G are listed.

In the present invention, since the toner is obtained by using the polymerization method, it is necessary to pay attention to the polymerization inhibitory property and the water phase transfer property of the colorant, and preferably the surface modification, for example, the polymerization inhibitory property is not caused. It is better to give a hydrophobic treatment with a substance. In particular, since many dyes and carbon black have a polymerization inhibitory property, caution is required when using them. A preferred method of surface-treating the dye system is a method of polymerizing a polymerizable monomer in the presence of these dyes in advance, and the obtained colored polymer is added to the monomer system. Regarding carbon black, in addition to the same treatment as the above dye, graft treatment may be performed with a substance that reacts with the surface functional groups of carbon black, for example, polyorganosiloxane.

In the present invention, a magnetic substance may be added,
This is also preferably used after being surface-treated.

The additive which can be used in the present invention for imparting various characteristics has a particle diameter of 1/10 or less of the weight average particle diameter of the toner particles from the viewpoint of durability when added to the toner. Preferably. The particle size of the additive means the average particle size thereof obtained by observing the surface of the toner particles with an electron microscope. As the additives for the purpose of imparting these characteristics, for example, the following ones are used. 1) Flowability-imparting agents: metal oxides (eg, silicon oxide, aluminum oxide, titanium oxide), carbon black and carbon fluoride. It is more preferable that each is subjected to a hydrophobic treatment. 2) Abrasive: metal oxide (eg strontium titanate, cerium oxide, aluminum oxide, magnesium oxide, chromium oxide), nitride (eg silicon nitride), carbide (eg silicon carbide), metal salt (eg calcium sulfate, sulfuric acid) Barium, calcium carbonate). 3) Lubricants: Fluorine-based resin powder (eg vinylidene fluoride, polytetrafluoroethylene), fatty acid metal salt (eg zinc stearate, calcium stearate). 4) Charge controllable particles: metal oxides (eg tin oxide, titanium oxide, zinc oxide, silicon oxide, aluminum oxide),
Carbon black.

These additives are used in an amount of 0.1 to 10 parts by weight, preferably 0.1 to 5 parts by weight, based on 100 parts by weight of the toner particles. These additives may be used alone or in combination of two or more.

In the toner production method of the present invention, generally, the above-mentioned toner composition, that is, the polymerizable monomer, contains a colorant, a release agent, a plasticizer, a binder, a charge control agent, a crosslinking agent, and a magnetic material. Toner components such as toner and other additives, for example, an organic solvent to reduce the viscosity of the polymer formed in the polymerization reaction, a dispersant are appropriately added to prepare a monomer composition, a homogenizer, a ball mill. , Colloid mill,
The monomer composition that has been uniformly dissolved or dispersed by a disperser such as an ultrasonic disperser is suspended in an aqueous medium containing a dispersion stabilizer. At this time, the particle size of the obtained toner particles becomes sharper by using a high-speed stirrer or a high-speed disperser such as an ultrasonic disperser to make the desired toner particle size at a stretch. Regarding the timing of addition of the polymerization initiator, it may be added at the same time as other additives are added to the polymerizable monomer, or may be mixed immediately before being suspended in the aqueous medium.
Further, a polymerization initiator dissolved in a polymerizable monomer or a solvent may be added immediately after granulation and before the polymerization reaction is started.

After the granulation, a normal stirrer may be used to stir the particles so that the particle state is maintained and the particles are prevented from floating and settling.

In the suspension polymerization method used in the present invention, a known surfactant, organic dispersant or inorganic dispersant can be used as a dispersion stabilizer. Among them, the inorganic dispersant hardly produces harmful ultrafine powder, and its steric Since the dispersion stability is obtained due to the obstacles, the stability is not easily deteriorated even when the reaction temperature is changed, the cleaning is easy, and the toner is not adversely affected. Examples of such inorganic dispersants include polyvalent metal phosphates such as calcium phosphate, magnesium phosphate, aluminum phosphate and zinc phosphate; carbonates such as calcium carbonate and magnesium carbonate; calcium metasilicate, calcium sulfate and barium sulfate. Inorganic salts; inorganic oxides such as calcium hydroxide, magnesium hydroxide, aluminum hydroxide, silica, bentonite and alumina.

These inorganic dispersants are composed of the polymerizable monomer 10
It is preferable to use 0.2 to 20 parts by weight with respect to 0 parts by weight. However, although it is difficult to generate ultrafine particles, atomization of the toner is somewhat difficult.
You may use together a weight part surfactant.

Examples of the surfactant include sodium dodecylbenzenesulfate, sodium tetradecylsulfate, sodium pentadecylsulfate, sodium octylsulfate,
Examples thereof include sodium oleate, sodium laurate, sodium stearate, and potassium stearate.

When these inorganic dispersants are used, they may be used as they are, but in order to obtain finer particles, the inorganic dispersant particles can be generated in an aqueous medium. For example, in the case of calcium phosphate, a water-insoluble calcium phosphate can be produced by mixing an aqueous solution of sodium phosphate and an aqueous solution of calcium chloride under high-speed stirring, and more uniform and fine dispersion is possible.

By using this method, a very fine salt is obtained and a stable suspension state is obtained, so that the granulating property is good. Also for the toner shape, the size and number of surface irregularities are preferable. Furthermore, since the oil droplets are stable, the phase separation between A and B is promoted, and the internal structure of the toner is also preferable.

At this time, a water-soluble sodium chloride salt is also by-produced at the same time. However, when the water-soluble salt is present in the aqueous medium, the dissolution of the polymerizable monomer in water is suppressed, and the superposition due to emulsion polymerization is suppressed. This is more convenient because it makes it difficult for fine toner particles to be generated. Since it becomes an obstacle when removing the remaining polymerizable monomer at the end of the polymerization reaction, it is better to replace the aqueous medium or desalt with an ion exchange resin. The inorganic dispersant can be almost completely removed by dissolving it with an acid or an alkali after completion of the polymerization.

In the above-mentioned polymerization step, the polymerization temperature is 40
Polymerization is carried out at a temperature of not less than 0 ° C, generally 50 to 90 ° C. When the polymerization is carried out within this temperature range, the release agent and waxes to be sealed inside are precipitated by phase separation and the encapsulation becomes more complete. In order to consume the remaining polymerizable monomer, the reaction temperature is 90 to 15 at the end of the polymerization reaction.
It is possible to raise it to 0 ° C.

Under the above conditions, the conversion rate increases almost linearly up to the polymerization conversion rate of 90%, but the toner solidifies 90
%, The increase in the degree of polymerization is slow, and when the polymerization conversion rate is 95% or more, it is very slow. The polymerization reaction may proceed as it is, and the residual polymerizable monomer amount may be controlled to 1,000 ppm or less.

An organic solvent, a polymerizable monomer or a mixture thereof contained in the toner particles used in the present invention is added to 1,00.
As a means for reducing the amount to 0 ppm or less, a method of continuing the polymerization reaction as described above until the amount of the organic solvent, the polymerizable monomer or the mixture thereof is 1,000 ppm or less in the toner particles; the polymerization conversion rate is 95% or more. A method of accelerating the consumption of the polymerizable monomer when it reaches the toner; an organic solvent, a polymerizable monomer or a mixture thereof is used as a toner without carrying the low softening point resin (B) in the central portion to the phase A in the surface portion. The method of removing from a particle is mentioned.

As a method for promoting the consumption of the polymerizable monomer, (a) the polymerization reaction temperature is 5 to 60 ° C., preferably 10 to 50 ° C. when the polymerization conversion rate reaches 95% or more.
More preferably, a method of raising the temperature by 20 to 40 ° C. is particularly preferable, and a polymerization initiator which decomposes at a high temperature is preferably used in combination;
(B) A method of using a polymerization initiator having a long anti-depletion period and an initiator having a short anti-depression period in combination; (c) A method of using a polyfunctional polymerization initiator having a plurality of polymerization initiation points.

As a method for removing the organic solvent, the polymerizable monomer or a mixture thereof from the toner particles of (d),
After the completion of the polymerization reaction or in the latter half of the polymerization reaction, the method of stopping the reflux and distilling off some of the unreacted polymerizable monomer and / or the organic solvent under normal pressure or under reduced pressure; There is a method of degassing with.

The organic solvent, the polymerizable monomer or the mixture thereof finally contained in the toner particles is at least 1,
000 ppm or less, more preferably 100 ppm or less in order to eliminate the offensive odor caused by the polymerizable monomer and its reaction residue generated during fixing or the solvent.

The polymerization conversion rate was obtained by adding a polymerization inhibitor to 1 g of the suspension and dissolving this in 4 ml of THF.
The amount of residual polymerizable monomer and the amount of residual organic solvent was determined by using 0.2 g of toner dissolved in 4 ml of THF.
Each was measured by gas chromatography under the following conditions by the internal standard method.

G. C. Conditions Measuring device: Shimadzu GC-15A (with capillary) Carrier: N2, ² Kg / cm2 50 ml / min.
split 10 ml / 13s column: ULBON HR-1 50 m × 0.25 mm

[0068]

[Outer 1] Sample volume: 2 μl Labeled substance: Toluene

The particle size distribution measurement in the present invention will be described.

A Coulter Counter TA-II type (manufactured by Coulter) is used as a measuring device, and an interface (manufactured by Nikkaki) for outputting number average distribution and volume average distribution and a CX-1 personal computer (manufactured by Canon) are connected. The electrolyte is 1% using first-grade sodium chloride.
An aqueous NaCl solution is prepared.

The measuring method is as follows:
To 150 ml, 0.1 to 5 ml of a surfactant, preferably an alkylbenzene sulfonate, is added as a dispersant, and 0.5 to 50 mg of a measurement sample is further added.

The electrolytic solution in which the sample was suspended was subjected to a dispersion treatment for about 1 to 3 minutes with an ultrasonic disperser, and the Coulter counter TA-II type was used to form particles having a particle size of 2 to 40 μm using a 100 μm aperture as an aperture. The distribution is measured to obtain a volume average distribution and a number average distribution.

The weight average particle diameter (D4) is obtained from the thus obtained volume average distribution and number average distribution.

Next, the molecular weight measuring method in the present invention is shown below.

1) Sample Preparation i) Standard Sample As the standard sample, the following commercially available standard polystyrene is used.

[0076]

[Outside 2]

These 12 standard polystyrenes are divided into 3 groups as follows. 8.42 × 10 ⁶ , 7.75 × 10 ⁵ , 3.5 × 10
⁴ , 3.6 × 10 ^3, 2.7 × 10 ⁶ , 4.7 × 10 ⁵ , 1.5 × 10 ⁴ ,
2.35 × 10 ³ 1.2 × 10 ⁶ , 2.0 × 10 ⁵ , 1.02 × 10
⁴ , 5.0 x 10 ²

Approximately 3 mg each of the 4 samples in the group (1 cup in a microspatel) was placed in a 30 ml sample bottle, and 1
Add 5 ml of THF and let stand at room temperature for 4 hrs (while every 30 min shake vigorously for 1 min). Then, it is filtered using a membrane filter (regenerated cellulose, 0.45 μ: made by Toyo Roshi Kaisha, Ltd.) to obtain a standard sample.

Ii) Unknown sample Weigh 60 mg of the sample into a sample bottle, and further add THF1
Add 5 ml. The extraction conditions are such that the initial 3 hrs are shaken every 30 minutes and left at room temperature for 24 hrs. further,
Apply ultrasonic waves for 15 minutes to perform extraction sufficiently. The insoluble matter is precipitated by centrifugation (500 rpm / 20 min), and the supernatant is filtered using a membrane filter (regenerated cellulose, 0.45 μ: Toyo Roshi Kaisha, Ltd.) to obtain a sample.

2) 150C ALC / GPC manufactured by Waters Co. as a GPC device
Was measured under the following conditions. i) Solvent THF (Kishida Chemical's special grade) ii) Column Shoredex A-802, A-80
3, A-804, A-805 four connections (manufactured by Showa Denko) iii) Room temperature 28 ° C iv) Flow rate 1.0 ml / min v) Injection amount 0.5 ml vi) Detector RI

3) GPC data processing method i) Calibration curve-Chromatogram of the standard sample is taken and the retention time at the peak is read. When the peaks are divided, it is the time of the main peak.・ Draw a calibration curve from the molecular weight of the standard sample and the retention time of the peak. ii) Unknown sample ・ Calculate the chromatogram of the unknown sample and calculate the molecular weight from the retention time using a calibration curve.

The melting point of the wax in the present invention is measured by
Temperature rising rate 1 using DSC-7 (manufactured by Perkin Elmer)
The melting point of the wax is defined as the temperature at the apex of the peak showing the maximum endotherm in the DSC curve during the first temperature increase performed at 0 ° C./min.

[0083]

EXAMPLES The present invention will be specifically described below based on examples. All parts in the following formulations are parts by weight.

Example 1 A 0.1M Na ₃ PO ₄ aqueous solution and a 1M CaCl ₂ aqueous solution are prepared. TK type homomixer (made by Tokushu Kika Kogyo)
0.1M Na ₃ PO ₄ 451g and ion-exchanged water 7
09 g was added and the mixture was stirred at 12000 rpm. 1 MC
67.7 g of an aCl ₂ aqueous solution was gradually added to the above homomixer stirred at 70 ° C. under stirring to obtain a dispersion medium containing Ca ₃ (PO ₄ ) ₂ .

Styrene 170 g 2-Ethylhexyl acrylate 30 g C.I. I. Pigment Blue 15: 3 10 g Styrene-methacrylic acid-methyl methacrylate copolymer 5 g (Mw = 50,000, Mw / Mn = 2.5, acid value = 50) Paraffin wax (mp. 70 ° C.) 60 g Di-tert- Butyl salicylate metal compound 3g

Among the above formulations, C.I. I. Pigment Blue 15: 3, di-tert-butylsalicylic acid metal compound and styrene only Ebara Milder (Ebara Corporation)
Was used for premixing. Next, add all of the above prescriptions to 60
The mixture was heated to ℃, dissolved and dispersed to obtain a monomer mixture. Further, while maintaining the temperature at 60 ° C., the polymerization initiator 2,2′-azobis (2,4-dimethylvaleronitrile) [t1 / 2 = 1
40 min. at 60 ° C.] 10 g, and dimethyl-2,
2'-azobisisobutyrate [t1 / 2 = 1,270
min. at 60 ° C., t1 / 2 = 80 min. at80
[Deg.] C.] 1 g was dissolved to prepare a polymerizable monomer system. The polymerizable monomer system was put into the aqueous medium, and the temperature was maintained at 60 ° C. under N ₂
10,000 in a TK homomixer in the atmosphere
The mixture was stirred at rpm for 20 minutes to granulate suspension droplets having a toner particle size. Then, while stirring with a paddle stirring blade, 60
The reaction was carried out at ℃ for 3 hours. The polymerization conversion rate at this point was 90.
%Met. After that, the reflux of water vapor was stopped and the liquid temperature was adjusted to 8
The temperature was raised to 0 ° C. and stirring was continued for another 10 hours. After the reaction was completed, the suspension was cooled, hydrochloric acid was added to dissolve Ca ₃ (PO ₄ ) _2, and the mixture was filtered, washed with water and dried to obtain toner particles having a weight average diameter of 8.2 μm. The amount of the polymerizable monomer remaining at this point was 100 ppm. The toner particles at 45 ° C.,
The degassing treatment was performed for 12 hours under a reduced pressure of 50 mmHg.
The amount of remaining polymerizable monomer at this point is 90 ppm
Met.

It was confirmed by observation with an electron microscope that the surface of the toner particles had irregularities such as depressions and had an irregular shape. (R / r = 1.07, L / 1 = 1.15)
Furthermore, when the cross section of the toner particles was observed by a transmission electron microscope by a dyeing ultra-thin section method, it was divided into a surface layer part mainly composed of styrene-acrylic resin and a central part mainly composed of wax, and the particle particles from the surface were separated. It was confirmed that there was no wax-based phase in the vicinity of the surface up to a depth of 0.15 times the diameter.

To 100 parts of the obtained toner particles, B
A toner externally added with 0.7 part of hydrophobic silica having a specific surface area of 200 m ² / g by the ET method was obtained. Acrylic-coated ferrite carrier 93 for 7 parts of this toner
Parts were mixed to obtain a developer.

Using this developer, an unfixed image was obtained with a Canon full color copying machine CLC-500. The amount of toner on the paper is 0.75 ± 0.05 mg / cm ² ,
A fixing test was conducted using an external fixing tester. At this time,
As a fixing roller, silicone rubber (HTV) PF
A resin having a hardness of 55 degrees was used, which was coated with resin A in a thickness of 30 μm. The fixing process speed was 90 mm / sec, and the fixing test was conducted by adjusting the temperature every 5 ° C. in the temperature range of 100 to 220 ° C.

As a result, the fixing temperature range is 155 ° C to 19 ° C.
The temperature reached 0 ° C, and the releasing effect of the wax was exhibited.

When the blocking test was carried out as follows by leaving it in a dryer at 50 ° C. for 10 days, the evaluation was ◯.

After being left in the dryer, 5 g of the sample was taken in a powder tester manufactured by Hosokawa Micron Co., Ltd. equipped with 60 mesh, and shaken for 20 seconds under the condition of DC 1.8V. The residual amount of toner remaining in the screen was measured, and the blocking resistance was evaluated according to the evaluation criteria shown in the table below.

[0093]

[Table 1]

Next, with CLC-500, 20,000
As a result of running test of one sheet, image density is 1.4
As described above, images with extremely high resolution were stably obtained without fogging, toner cleaning failure did not occur, and toner scattering in the copying machine was not noticeable.

Example 2 Cyan toner particles (polymerizable monomer content: 230 ppm) of 8.3 μm were obtained in the same manner as in Example 1 except that the polar resin was not used.

The toner particles obtained were evaluated for blocking resistance in the same manner as in the examples, and were evaluated as good.

When a developer was prepared and imaged in the same manner, the image density tended to decrease with durability as compared with the toner of Example 1, and a slight cleaning defect was found after about 3000 sheets. It was When the toner at the start of the durability was observed by FE-SEM, it was a spherical toner without surface irregularities. Furthermore, when the cross section of the toner particles was observed by a transmission electron microscope by a dyeing ultra-thin section method, it was divided into a surface layer part mainly composed of styrene-acrylic resin and a central part mainly composed of wax, and the particle particles from the surface were separated. It was confirmed that there was no wax-based phase in the vicinity of the surface up to a depth of 0.15 times the diameter.

Comparative Example 1 In Example 1, the same state was maintained after 3 hours of reaction, and after a total of 8 hours, when the polymerization conversion reached 99% or more, the toner particles were taken out, and the dispersant was washed and dried. Processed. At this point, the residual polymerizable monomer content is 7,000.
It was ppm. The toner particles obtained were evaluated for blocking resistance in the same manner as in Example 1. Using the toner particles, a developer was prepared in the same manner as in Example 1 and an image was formed. As a result, it was a good image that was the same as in Example 1. However, there was a styrene odor from around the fixing device. When this toner was left for one month in an environment of 35 ° C., the toner tribo was extremely reduced, and an image with a lot of fog was formed.

Example 3 Instead of the polar resin used in Example 1, Mw = 30
000, Mw / Mn = 3.8, acid number 0.2 styrene-
Cyan toner particles having a weight average diameter of 8.6 μm (polymerizable monomer content: 210 ppm) were obtained in the same manner except that the butyl acrylate copolymer was used instead.

The toner particles obtained were evaluated for blocking resistance in the same manner as in Example 1.

The particle size distribution of the obtained toner particles was fairly broad, and the surface of the toner particles was not uneven, and the toner particles were true spherical. Furthermore, when the cross section of the toner particles was observed by a transmission electron microscope by a dyeing ultra-thin section method, it was divided into a surface layer part mainly composed of styrene-acrylic resin and a central part mainly composed of wax, and the particle particles from the surface were separated. Diameter of 0.15
It was confirmed that the wax-based phase did not exist in the vicinity of the surface up to the double depth. When a developer was prepared and imaged in the same manner as in Example 1, the image density tends to decrease with durability as compared with the toner of Example 1 3
From around 000 sheets, a slight cleaning defect was found.

Example 4 Toner particles were obtained in the same manner as in Example 1, except that the amount of wax was reduced to 20 g (10 parts). The amount of the polymerizable monomer remaining in the obtained toner particles was 60 ppm.

The blocking resistance of the obtained toner was evaluated in the same manner as in Example 1, and was evaluated as good.

It was confirmed by observation with an electron microscope that the surface of the toner particles had irregularities such as depressions and had an irregular shape. (R / r = 1.06, L / 1 = 1.13)
Furthermore, when the cross section of the toner particles was observed by a transmission electron microscope by a dyeing ultra-thin section method, it was divided into a surface layer part mainly composed of styrene-acrylic resin and a central part mainly composed of wax, and the particle particles from the surface were separated. It was confirmed that there was no wax-based phase in the vicinity of the surface up to a depth of 0.15 times the diameter.

Using the toner particles thus obtained, a developer was prepared in the same manner as in Example 1, and a fixing test was conducted in the same manner. As a result, the fixing temperature range was 160 to 170 ° C., which was in comparison with the toner of Example 1. The fixing temperature range was slightly narrow.

Example 5 The polar resin used in Example 1 was Mw = 100,000, Mw
/Mn=3.5, acid number 70 styrene-methacrylic acid-
Cyan toner particles having a weight average particle diameter of 8.0 μm were obtained in the same manner except that the methyl methacrylate copolymer was used instead.

The content of the polymerizable monomer in the obtained toner particles was 180 ppm.

The toner particles obtained were evaluated for blocking resistance in the same manner as in Example 1. The result was ◯.

It was confirmed by observation with an electron microscope that the surface of the toner particles had irregularities such as depressions and had an irregular shape. (R / r = 1.08, L / 1 = 1.08)
Furthermore, when the cross section of the toner particles was observed by a transmission electron microscope by a dyeing ultra-thin section method, it was divided into a surface layer part mainly composed of styrene-acrylic resin and a central part mainly composed of wax, and the particle particles from the surface were separated. It was confirmed that there was no wax-based phase in the vicinity of the surface up to a depth of 0.15 times the diameter.

A developer was prepared in the same manner as in Example 10
After running 000 sheets, a stable image was obtained with little fluctuation in image density, and no cleaning failure was observed. In addition, the toner after durability is FE-SEM
As a result, it was confirmed that the toner had a surface-roughened surface similar to that before endurance, and that silica adhered to the surface was confirmed.

Example 6 The polar resin used in Example 1 was Mw = 580000, M
The styrene-methacrylic acid-methyl methacrylate copolymer having w / Mn = 3.0 and an acid value of 63 was replaced with 50 g of paraffin wax, and the pigment used was C.I. I. Pigment Red 122 was replaced with 10 g to give magenta toner particles having a weight average diameter of 7.9 μm (R / r =
1.03, L / l = 1.05).

In the production of toner particles, the polymerization reaction was carried out at 60 ° C. for 4 hours, and then the degree of reduced pressure (absolute pressure)
Unreacted heavy monomer was distilled off under reduced pressure distillation at 188 Torr and 65 ° C. for 5 hours, and then a drying treatment was carried out in the same manner as in Example 1. The residual amount of the polymerizable monomer at the time of obtaining the final toner particles was 45 ppm.

The toner particles obtained were evaluated for blocking resistance in the same manner as in Example 1. The result was ◯.

It was confirmed by observation with an electron microscope that the surface of the toner particles had irregularities such as depressions and had an irregular shape. (R / r = 1.03, L / 1 = 1.05)
Furthermore, when the cross section of the toner particles was observed by a transmission electron microscope by a dyeing ultra-thin section method, it was divided into a surface layer part mainly composed of styrene-acrylic resin and a central part mainly composed of wax, and the particle particles from the surface were separated. It was confirmed that there was no wax-based phase in the vicinity of the surface up to a depth of 0.15 times the diameter.

Using the resulting toner particles, a developer was prepared and imaged in the same manner as in Example 1. As a result, a good image was obtained as in Example 1.

Immediately after preparing the developer, the tribo is -28.0 μc.
/ G, whereas the tribo of the toner left in the environment of 35 ° C for 1 month was also extremely stable at -26.8 µc / g, and was excellent in storage resistance, blocking resistance, and charge stability. It became clear that it was a toner.

Comparative Example 2 In Example 1, the same state was maintained after 3 hours of reaction, and after a total of 8 hours, when the polymerization conversion rate reached 99% or more, the reflux of steam was stopped and the liquid temperature was 95 ° C. After holding for 3 hours, the toner particles were taken out and the dispersant was washed and dried. The content of the polymerizable monomer in the toner particles obtained at this point was 500 ppm.

When the surface condition of the obtained toner particles was observed with a transmission electron microscope, the presence of a wax component was recognized on the surface, and the blocking resistance evaluation performed in the same manner as in Example 1 was x.

[0119]

The toner of the present invention has a high softening point resin (A).
It has a structure in which it is separated into an A phase mainly composed of and a B phase mainly composed of a low softening point substance (B). The B phase extends from the toner particle surface to a depth of 0.15 times the toner particle diameter. Since it does not exist in the vicinity of the surface and contains 1,000 ppm or less of an organic solvent, a polymerizable monomer or a mixture thereof, it has excellent low-temperature fixability and releasability and excellent blocking resistance. Further, it shows stable and high developability, and there is little or no change in performance after long-term use.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a state in which a toner according to the present invention is separated into two phases.

FIG. 2 is a diagram for explaining outer shape conditions of the toner according to the present invention.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Takehiko Chiba 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Takayuki Nagatsuka 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Within the corporation

Claims (5)

[Claims] 1. A toner for developing an electrostatic image comprising toner particles obtained by a suspension polymerization method, wherein the toner particles are at least two kinds of components of a high softening point resin (A) and a low softening point substance (B). Contains, and
It has a structure in which an A phase mainly composed of the high softening point resin (A) and a B phase mainly composed of the low softening point substance are separated, and the particle size is 0.15 times the toner particle size from the surface of the toner particles. The B phase does not exist in the vicinity of the surface to the depth, and the toner particles are made of an organic solvent, a polymerizable monomer, or a mixture thereof of 1,00.
A toner for developing an electrostatic charge image, which contains 0 ppm or less. 2. The toner particles have the following relationship (1): 1.00 <R / r <1.20 ... (1) between a maximum inscribed circle having a radius r and a minimum circumscribed circle having a radius R with respect to a projection surface. 1) and on the surface of the toner particles, the following relationship (2) 1.01 <L / 1 <2.00 between the peripheral length L of the projection surface and the circumference 1 of the inscribed circle is satisfied. The toner for developing an electrostatic charge image according to claim 1, wherein irregularities satisfying (2) are formed. 3. The component ratio of the high softening point resin (A) and the low softening point substance (B) of the toner particles is A: B = 50: 50 to.
It is 95: 5, Claim 1 or Claim 2 characterized by the above-mentioned.
The toner for developing an electrostatic image as described above. 4. The toner for developing an electrostatic charge image according to claim 1, wherein the low softening point substance (B) is a soft melting point wax. 5. The low softening point substance (B) is 30 to 130 ° C.
5. The melting point of claim 1 to claim 4
5. The toner for developing an electrostatic charge image according to any one of 1.