JPS63108358A - Polymer toner - Google Patents

Abstract

PURPOSE:To improve dispersibility of a colorant for a toner and to enable low temperature fixing and/or low pressure fixing by incorporating a large amount of polyamide type low melting point compound in a polymer toner. CONSTITUTION:The polymer toner is manufactured by suspension polymerizing a composition containing a polymerizable monomer, such as styrene, a colorant, such as carbon black, a low softening point compound having a softening point of 40-130 deg.C, and the like. As the low softening point compound, the polyamide is used in an amount is 50-3,000wt% of said monomer, thus permitting the dispersibility of the colorant to be enhanced, accordingly, its content in the toner to be increased, and the toner to be lowered in temperature and pressure at the time of fixing.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a polymerized toner produced by a suspension polymerization method.

[Prior Art] Toners conventionally used in dry image forming methods such as electrophotography, electrostatic printing, and electrostatic recording are generally prepared by melt-mixing colorants and other additives in a thermoplastic resin. After being uniformly dispersed, the particles are pulverized by pulverization ii, and then classified by a classifier to obtain a desired particle size. Although the resulting toner is quite good, it does have potential problems due to the grinding process. That is, the toner obtained using the pulverization method must have some brittleness to make the material more susceptible to pulverization.

However, if the toner is too brittle, it becomes too finely powdered and must be cut into fine particles to obtain toner with an appropriate particle size distribution, which increases costs. In some cases, it becomes even more finely powdered. Furthermore, if a material with a low melting point or a pressure fixable material is used to improve heat fixability, a fusion phenomenon may occur in a crushing device or a classification device, making continuous production impossible.

Therefore, as a means to overcome the problems of the pulverization method, a polymerized toner produced from a polymerizable monomer by a suspension polymerization method has been proposed.

In the conventional general suspension polymerization method, a monomer composition containing at least one colorant and a polymerizable monomer is granulated to the toner particle size in an aqueous medium, and a polymerization initiator that has been added in advance or a new polymerization initiator is When the polymerization initiator added to the toner is decomposed by heat, the radicals generated are used to polymerize the polymerizable monomer to form a polymer, thereby producing a polymerized toner. In other words, since this method does not involve a pulverization process, the polymerized toner does not need to be brittle and has a spherical shape, so it has excellent fluidity.
It has characteristics such as uniform triboelectric charging properties.

In recent years, efforts have been made to improve the image quality of copied images, increase the speed of copying machines, and/or reduce energy consumption. There is a long-awaited toner that can form a good fixed image by low-temperature fixing and/or low-pressure fixing. For these purposes, in the monomer composition,
By adding a large amount of a low softening point compound such as solid paraffin wax or low molecular weight polyolefin that has shape retention properties at room temperature, we create a polymerized toner that contains a larger amount of low softening point compounds than conventional polymerized toners. Attempts have been made to manufacture these low softening point compounds, but in general, these low softening point compounds have poor compatibility with one of the colorants, carbon black and magnetic powder, and only the colorant separates during the process of polymerizing toner production, resulting in the toner being damaged. Even if it is obtained as a toner, the content of the colorant decreases, causing problems such as not being able to obtain a sufficient image fR density.

[Problems to be Solved by the Invention] The present invention aims to improve the problems of the above-mentioned prior art. That is, the object of the present invention is to provide a polymerized toner that contains a large amount of a low softening point compound and has improved colorant dispersibility.

[Means and effects for solving the problems] According to the present invention, at least one polymerizable monomer, a coloring agent, and a softening point of 4
A polymerized toner manufactured by a suspension polymerization method from a monomer composition containing a low softening point compound of 0 to 130°C, wherein the low softening point compound is a polyamide resin, and the content thereof is 50 to 3, per 100 parts by weight of the monomer
000 parts by weight.

The present invention is characterized in that a polyamide wax, which has a more positive polarity, is used instead of paraffin wax and low molecular weight polyethylene wax, which have been conventionally used as low softening point compounds. In general, paraffin wax and low molecular weight polyethylene wax have weak polarity and are poorly compatible with relatively polar colorants such as carbon black and magnetic powder, which prevents the colorant in the monomer composition from being uniformly dispersed. In the present invention, the colorant is liberated in water during the suspension polymerization process, making it impossible to exhibit various properties as a toner. By using the monomer composition, a polymerized toner containing a large amount of a low softening point compound with good colorant dispersibility was obtained.

The polyamide-based low softening point compound in the present invention is expressed by, for example, a -shell structural formula, and has a softening point of 40 to 130°C, preferably 50 to 1, as measured by the ring and ball method (see JIS K 2531).
If the softening point is less than 40°C, the blocking resistance of the toner is insufficient;
Examples of polyamide-based low softening point compounds that have little effect in lowering the fixing temperature when the temperature exceeds 0 are 1, such as Diamond KH, Diamond H, Amide AP-1, Diamond 200, Diamond 0, and Diamond 0-200.
, Diamond L-200, Diamond Y, Diamond KP, Diamond KN, Methylolamide, Clover Ace KN, Suripack 0 (manufactured by Nippon Kasei), Sunmide 550. Sanmide H〒-85
, Sunmide HT-120, Sunmide H-100H
, Sunmide SN-2, Sunmide 155° Sunmide 1550H, Sunmide 15500", Sunmide 5
69, Sanmide 611DK-1, Sanmide 1578
K, Sanmide-579H, Sanmide-611H
1 Sanmide 1615A, Wax Type Polyamide H Tate 70B, FED-4A, FMD-Of
, FMD-03 (manufactured by Sanso Kagaku Kogyo ■), Persamide 335, Persamide 930, Persamide 940. Persamide 711, Persamide 756, DPX 80
2 (all manufactured by Henkel Jisui), etc.
It is not limited to these, and a mixture of these may be used. In addition, when using a low softening point compound with a softening point of 100°C or higher, the liquid temperature of the aqueous medium is lowered under pressure. It is preferable to carry out dispersion and granulation at a temperature of 100°C or higher.

The above-mentioned low softening point compound controls the fixing temperature of the polymerized toner and/or
Alternatively, in order to lower the fixing pressure, 50 to 3,000 parts by weight are mixed with 100 parts by weight of monopolymerizable monomer. It is particularly preferable that 70 to 1,000 parts by weight of the 50
If it is less than 3,000 parts by weight, it is insufficient to lower the fixing temperature or fixing pressure of the fixing roller, and if it exceeds 3,000 parts by weight, blocking resistance and durability tend to decrease.

The polymerizable monomers that can be used to form the polymerized toner of the present invention are monomers having a C1h-C< group as one reactive group, such as styrene, 0-methylstyrene, m-methylstyrene, p-methylstyrene, p-methoxystyrene, p-phenylstyrene, p-chlorostyrene, 3,4
-dichlorostyrene, p-ethylstyrene, 2,4-dimethylstyrene, p-n-butylstyrene, p-t
ert-butylstyrene, p-n-hexylstyrene,
pn-octylstyrene, pn-7nylstyrene, pn-tecylstyrene.

Styrene and its rust conductors such as p-n-dodecylstyrene; vinyl esters such as vinyl acetate, vinyl propionate, vinyl benzoate; acrylic acid, methacrylic acid, maleic acid, maleic hafester; methyl methacrylate, ethyl methacrylate , propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate,
α-methylene aliphatic monocarboxylic acid esters such as 2-ethylhexyl methacrylate, stearyl methacrylate, phenyl methacrylate, dimethylaminoethyl methacrylate, diethylamide methacrylate;
Methyl acrylate, ethyl acrylate, n-acrylate
Butyl, isobutyl acrylate, propyl acrylate,
Acrylic acid esters such as n-octyl acrylate, dodecyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, 2-chloroethyl acrylate, and phenyl acrylate; vinyl ethers such as vinyl methyl ether, vinyl ethyl ether, and vinyl isobutyl ether; Vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone, methyl isopropenyl ketone; N-vinylpyrrole, N-vinylcarbazole, N-
N-vinyl compounds such as vinyl indole and N-vinylpyrrolidone; vinylnaphthalenes; 7-crylonitrile,
There are monomers having reactive double bonds such as acrylic acid such as methacrylonitrile and acrylamide, or vinyl groups such as methacrylic acid derivatives. These may be used alone or in combination. If necessary, a crosslinking agent may be used. As a crosslinking agent, divinylbenzene,
Examples include divinylnaphthalene, diethylene glycol dimethacrylate, and ethylene glycol dimethacrylate. The amount of crosslinking agent added is usually 100f of polymerizable monomer.
It is used in an amount of 0.1 to 5 parts by weight per part of fi. Also,
A small amount of a polymer of these polymerizable monomers may be added to the monomer composition. Among the above-mentioned monomers, styrene, styrene having a substituent such as an alkyl group, or styrene and Mixed monomers with other monomers are preferred in consideration of developability and durability.

In addition, a preferable polymerized toner can be obtained by adding a polar polymer, a polar copolymer, or a cyclized rubber having a polar group as an additive during polymerization of the monomer to polymerize the polymerizable monomer. Polar polymer, polar copolymer or cyclized rubber is 1
It is preferable to add 0.5 to 50 parts by weight, preferably 1 to 40 parts by weight, per 100 parts by weight of the polymerizable monomer.
If it is less than 5% by weight, it is difficult to obtain a sufficient pseudocapsule structure, and if it exceeds 50 parts by weight, the amount of polymerizable monomer becomes insufficient and the properties as a polymerized toner tend to deteriorate. A polymerizable monomer composition containing a polar polymer, a polar copolymer, or a cyclized rubber is suspended in an aqueous phase of an aqueous medium in which the polar polymer and a dispersant with an opposite charge are dispersed, and polymerization is carried out. In other words, the cationic or anionic polymer, cationic or anionic copolymer, and anionic cyclized rubber contained in the 1f1 polymerizable monomer composition are preferably dispersed in an aqueous medium. The oppositely charged 7-ionic or cationic dispersant is electrostatically attracted to the toner particle surface, and the dispersant covers the particle surface to prevent the particles from coalescing and stabilize them. Since the polymer, polar copolymer, or cyclized rubber gathers on the surface layer of the toner particles, they form a kind of shell-like form, and the resulting particles become pseudo-capsules. and 1
The relatively high-molecular-weight polar polymer, polar copolymer, or cyclized rubber gathered on the surface layer of the particles encapsulates a large amount of low softening point compounds inside the toner particles. Examples of polar polymers (including polar copolymers and cyclized rubbers) and anti-loading dispersants that can be used in the present invention, which impart excellent properties such as hardness and abrasion resistance, are shown below. Note that polar polymers having a weight average molecular weight of s,ooo to 500.000 as measured by GpC are preferably used because they dissolve well in the polymerizable monomer and have durability.

(+) Cationic polymers include polymers of nitrogen-containing monomers such as dimethylaminoethyl methacrylate and diethylaminoethyl acrylate, copolymers of styrene and the nitrogen-containing monomers, styrene, unsaturated carboxylic acid esters, etc. There is also a copolymer of the nitrogen-containing monomer and the nitrogen-containing monomer.

(i) Examples of anionic polymers include nitrile monomers such as acrylonitrile, chlorine-containing monomers such as vinyl chloride, unsaturated carboxylic acids such as acrylic acid, unsaturated dibasic acids, and unsaturated dibasic acids. There are polymers of acid anhydrides or copolymers of styrene and the monomer.

The dispersant is preferably an inorganic fine powder that has the ability to stabilize the dispersion of monomer composition particles in an aqueous medium and is poorly soluble in water.The amount of the dispersant added to the aqueous medium is based on water. It is preferable to add 0.1 to 50% by weight (preferably 1 to 20% by weight).

(m) As the anionic dispersant, Aerosil #200
There are colloidal silicas such as #300 (manufactured by 13 Mokko Logil Co., Ltd.).

(iv) Aluminum oxide as a cationic dispersant;
Examples include magnesium hydroxide, wood-philic positively chargeable silica fine powder such as aminoalkyl-modified colloidal silica treated with a coupling agent.

An anionic cyclized rubber may be used instead of the above-mentioned polar polymer or copolymer.

To produce magnetic polymerized toners, magnetic particles are added to the monomer composition. In this case, the magnetic particles also serve as a coloring agent.The magnetic particles that can be used in the present invention include substances that are magnetized when placed in a magnetic field, such as iron,
Ferromagnetic total bending powder or magnetite such as cobalt or nickel.

Powders of alloys and compounds such as hematite and ferrite can be mentioned.The particle size is 0.05 to 5 gm, preferably 0.1
~1μ layer of magnetic fine particles are used. The content of these magnetic particles is preferably 10 to 60% by weight, preferably 20 to 50% by weight, based on the weight of the toner.Furthermore, these magnetic fine particles can be treated with a treatment agent such as a silane coupling agent, a titanium coupling agent, or an appropriate amount. In this case, the amount of treatment may be 5% by weight or less (preferably 0.1 to 3% by weight), depending on the surface area of the magnetic fine particles and the density of hydroxyl groups present on the surface. The zero-polymerized toner, which has sufficient dispersibility in the polymerizable monomer and low softening point compound with a small amount and does not have a negative effect on the physical properties of the toner, contains a colorant. Pigments such as known dyes, carbon blur 2, and grafted carbon black, in which the surface of the carbon black is coated with a resin, can be used. The coloring agent is contained in an amount of 0.5 to 30% by weight based on the monopolymer and the low softening point compound. Charge control agents and fluidity modifiers are added to the toner as necessary (
The charge control agent and fluidity modifier may be mixed with toner particles (external addition).The charge control agent may be a metal organic compound having a carboxyl group or a nitrogen-containing group. There are complexes, metal-containing dyes, nigrosine, etc. Examples of fluidity modifiers or cleaning aids for the surface of the latent image carrier (photoreceptor) include colloidal silica and fatty acid metal salts. In addition, fillers such as calcium carbonate and fine powder silica may be added to the toner in a range of 0.5 to 20% by weight for the purpose of increasing the amount. Teflon® to improve
A flowability improver such as fine powder or zinc stearate powder may be added.

A low molecular weight hydrocarbon compound (e.g. weight average molecular l 500-5.000) that improves mold release properties during hot roll fixing.
) or carnauba wax as a low softening point compound,
For example, hydrocarbon compounds are hydrophobic and have a low molecular weight, so they are difficult to mix with polymers produced by monopolymerization, and they are less likely to be exposed to the particle surface than polar polymers, polar copolymers, or cyclized rubber, and are trapped inside the polymerized toner. It will be pushed into the shape. As a result, even if it contains a large amount of a low softening point compound, it has excellent durability and blocking resistance because it is encapsulated. During fixing, it comes out from inside, significantly improving fixing properties and offset properties. In other words, it serves as an offset agent and a fixing agent.

When the polymerized toner of the present invention is applied to a two-component developer, it can be applied at the usual mixing ratio of toner and carrier.1 For example, it is used by mixing 1 to 500 parts by weight of carrier to 1 part by weight of toner. .

The suspension method involves uniformly adding 1 colorant (including magnetic materials in the present invention), 50 to 3,000 parts by weight of a low softening point compound, and additives to 100 parts by weight of the polymerizable monomer. The dissolved or dispersed monomer composition is
% by weight of a suspension stabilizer (e.g., a sparingly soluble inorganic dispersant) in an aqueous medium (e.g.).

(the mixture is heated to a temperature 5° C. or higher, preferably 10° C. to 30° C. higher than the polymerization temperature) using a conventional stirrer, homomixer, homogenizer, etc. Preferably melted or softened? The stirring speed, time, and temperature of the aqueous medium are adjusted so that the particles of the It polymer composition have the desired toner particle size, generally less than or equal to 30 IL11 (e.g., average particle size of 0.1 to 20 μm).

Thereafter, the temperature of the aqueous medium is lowered to the polymerization temperature while performing Wl stirring to an extent that prevents sedimentation of the particles so that the state is almost maintained by the action of the dispersion stabilizer.The polymerization temperature is 50°C or higher. The temperature is preferably set at 55 to 80°C, particularly preferably 60 to 75°C, and a substantially water-insoluble polymerization initiator is added and polymerized while stirring. After the reaction is completed, the generated toner particles are washed. 1. Removal of dispersion stabilizer,
The polymerized toner of the present invention can be obtained by collecting and drying the toner by a suitable method such as filtration, decantation, centrifugation, etc. In the suspension polymerization method, 200 to 3.0 parts of water is usually added to 100 parts by weight of the polymerizable monomer and low softening point compound.
00 parts by weight are used as aqueous dispersion medium.

Also suitable stabilizers, such as polyvinyl alcohol,
Gelatin, methylcellulose, methylhydropropylcellulose, ethylcellulose, carboxymethylcellulose and other sodium salts, polyacrylic acid and their salts, starch, gum alginate, zein, casein, tricalcium phosphate, talc, barium sulfate, bentonite, hydroxide An aqueous medium containing any one or a mixture of aluminum, ferric hydroxide, titanium hydroxide, thorium hydroxide, etc. to an extent that does not adversely affect the production method of the present invention may also be used.

Furthermore, for uniform dispersion of the inorganic dispersion stabilizer, a surfactant may be used to the extent that it does not adversely affect the production method of the present invention. Specific examples include sodium dodecylbenzenesulfonate, sodium tetradecylsulfate, sodium pentadecylsulfate, sodium octylsulfate, sodium allyl-alkyl-polyethersulfonate, sodium oleate, sodium laurate, Sodium caprate, sodium caprylate, sodium caproate.

Potassium stearate, calcium oleate.

3.3-Disulfone diphenyl urea-4,4-diazo-
Sodium bis-amino-8-naphthol-6-sulfonate, ortho-carboxyben1zene-7zodimethylaniline, 2,2,5.5-tetramethyl-triphenylmethane-4,4-diazo-bis-β -Naphthol-
Examples include disulfone-ugly sodium and others. However, it must be noted that when a hydrophilic organic stabilizer or surfactant is used, the moisture resistance of the polymerized toner decreases.

In addition, water-soluble polymerizable monomers simultaneously cause emulsion polymerization in water and contaminate the resulting suspension polymer with small emulsion polymer particles, so add a water-soluble polymerization inhibitor 1, such as a metal salt, etc. It is also possible to prevent emulsion polymerization in the aqueous phase, and it is also possible to add glycerin, glycol, etc. to water in order to increase the viscosity of the aqueous medium and prevent coalescence of particles during heavy loading.

In addition, salts such as NaCR, KCj', Na2SO4, etc. may be added to the aqueous medium to reduce the solubility of the easily soluble polymerizable monomer in water. It is also possible to add a Brønsted acid, such as hydrochloric acid, to the aqueous medium to increase the ionization of the polar groups of the rubber. In particular, adding a Brønsted acid such as hydrochloric acid to an aqueous medium can further enhance the effect of anionic polymers, anionic copolymers or cyclized rubbers.
It is valid.

The polymerized toner of the present invention can be applied to known dry electrostatic image development methods. One-component development methods using magnetic toner, such as powder cloud method and fur brush method; -Component development method: Applicable to an electric field curtain development method in which components are transported to a developing section and developed by an electric field curtain method. Although it is particularly preferably applicable to dry development, it can also be used as a toner for wet development in some cases.

[Example] Hereinafter, the present invention will be described in detail based on Examples.

A monomer composition was prepared by mixing the components listed in L at a temperature of 65° C. for 4 hours using a 7 triter. Obtained monomer composition 2
54 parts by weight, 20 parts by weight of amino-modified silica (100 parts by weight of 7-nirodyl 200 treated with 5 parts by weight of 7-minopropyltoxytoxysilane) and 0. 120 g of distilled water heated to 65° C. containing 25 parts by weight of IN hydrochloric acid
The mixture was added to 0 parts by weight of an aqueous medium under stirring using a homomixer, and stirred at 10,000 rpm for 15 minutes to form 1-dispersion granules.

After granulation, the liquid temperature was lowered to 60°C, and 2.2' was added as a polymerization initiator.
3 parts by weight of -7zobis(2,4-dimethylvaleronitrile) and 1.2'-7zobisisobutyronitrile.
5 li parts were added to the aqueous medium and stirred for 30 minutes.

Furthermore, the stirring was changed to paddle blade stirring, and the mixture was stirred at 60° C. for 10 hours to complete the polymerization.

The resulting aqueous medium containing the polymerized toner is cooled.

Dehydrate, wash with sodium hydroxide solution to dissolve and remove the amino-modified silica, wash with water, dehydrate, and dry (classify if necessary to remove fine particles of unnecessary components). A polymerized toner with an average particle size of 8 μm (measured with a Coulter counter using 7 perchers of 100 #Lm) was obtained. The obtained polymerized toner contained about 200 parts by weight of polyamide wax based on 100 parts by weight of polystyrene. Further, even when the obtained toner was left in an environment of 50° C. for one day, no blocking occurred. From this, it was found that the polyamide wax was encapsulated inside the polymerized toner particles.

The obtained polymerized toner 10 parts by weight, 0.1 parts by weight of zinc stearate powder, 0.1 parts by weight of hydrophobic silica (Aerosil R972, manufactured by Nippon Aerosil Co., Ltd.), and an average particle size of 40
A developer was prepared by mixing 1 part of 9Ofi (formed from 25 parts by weight of triiron tetroxide/Sfi and 25 parts by weight of oxidized resin) of the insulating carrier particles of No. 1, and development was carried out under the following conditions.

The developing device shown in FIG. 1 was used.

The image carrier has a selenium photoreceptor, and the peripheral speed of the image carrier l is 1
The maximum potential of the electrostatic image formed on the image carrier is +750V, the outer diameter of the sleeve (developer carrier) 2 is 20mm/sec, and its circumferential speed is 100mm/sec.

The magnetic flux density in the vertical direction of the sleeve surface of the N and S poles of the magnet roller 3 is 1000 Gauss, and the thickness of the developer layer is 200 Gauss.
ps+, the gap between the sleeve 2 and the image carrier 1 is 300μ, the bias voltage applied to the sleeve is DC voltage component +2
00V, and 1400V with an AC voltage component of 3.0KHz. The electrostatic latent image is well developed, and the developed toner image is electrostatically transferred to plain paper, and the toner image on the plain paper is transferred from a fixing roller with a silicone rubber surface layer and a pressure roller under a pressure of 15 kg/cm2. The hot pressure roller fixing device R1 consists of a tongue width of 7 ta and a paper advance speed of 20
It was fixed even after 0 seconds of wetness). The fixing temperatures are shown in Table 1.

In the current state ta of FIG. 1, the toner T containing the external additive is quantitatively supplied to the lower chamber by the supply roller 8 and the elastic member 7, and mixed with the carrier to form the developer 4. A DC bias is applied to the sleeve 2 containing the magnet roller 3 and the doctor blade 10 from a DC bias power supply 5, and an AC bias is applied from an AC bias power supply 6. sleeve 2
As the developer 4 rotates in the incoming direction, the developer 4 is conveyed to the aluminum cylinder 1! and a selenium photoreceptor 12 for developing an electrostatic latent image on an image carrier l. The developer layer regulating member 9 also serves as an outer wall of the developing device.

Comparative Example 1 Wax type polyamide FND-01 in Example 1 was
The same procedure as in Example 1 was carried out except that the overlapping portion was changed to 0. Table 1 shows the results of the blocking test, fixing temperature, carbon dispersion rate, and initial image density of the obtained toner.

Comparative Example 2 Wax type polyamide FMD-01 in Example 1 was
The same procedure as in Example 1 was carried out except that the amount was changed to 500 parts by weight.

The obtained toner was completely blocked at 50°C. A fixation test and initial image development were not performed.

Comparative Example 3 Wax type polyamide FMD-0120 in Example 1
The same procedure as in Example 1 was carried out except that 200 parts by weight of paraffin wax 140 (manufactured by Nippon Seiro Co., Ltd., softening point 60°C) was used instead of 01 parts by weight. Table 1 shows the results of the blocking test, fixing temperature, carbon dispersion rate, and initial image density of the obtained toner.

(Left below) Leave in an oven at a temperature of 50°C and a humidity of 50% for 24 hours.

2) By microscopic observation of toner.

(It is assumed that the black particles are carbon black that is uniformly dispersed.) 3) Fixing property test method: paper speed of 200 mm/sec, paper temperature of 25 ± 1°C, fixing device pressure of 15 kg/cm2. The image is fixed by changing the surface temperature of the fixing roller in 5°C increments of 50°C, 55°C, 60°C, 65°C, etc. The fixed image is tested by the following Kosuri test method.

Stack 5 sheets of Silpon crepe paper (20g/cm2) [manufactured by Kojin] with the glossy side facing down, and press with a pressure of 40g/cm2 against the fixed image surface to test the glossy side, and check the crepe paper for tears. It is rubbed back and forth five times in the direction of the grain (indicating the direction of the fibers), and the ratio of the density after the test to the density before the test [(density after rubbing/density before rubbing) x 100] is defined as the fixing property.

The lowest temperature at which the fixability is 80 or higher is defined as the fixing temperature.

4) Values measured by Macbeth optical reflection densitometer.

[Effects of the Invention] As described above, according to the present invention, the dispersibility of colorant 1 is improved, fixing can be performed at low temperature and/or low pressure, and sufficient image density can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a diagram schematically showing a developing device used in Examples and Comparative Examples of the present invention. l...Photosensitive drum, 2...Sleeve. 3... Magnet roller, 4... Developer, 5.6.
...Development bias power supply, 7...Elastic member. 8... Supply roller, 9... Developer regulating member. lO...Doctor blade, 11...Aluminum cylinder, 12...Selenium photoreceptor.

Claims (1)

[Claims] (1) At least a polymerizable monomer, a colorant and a softening point of 4
A polymerized toner manufactured by a suspension polymerization method from a monomer composition containing a low softening point compound of 0 to 130°C, wherein the low softening point compound is a polyamide resin, and the content thereof is 50 to 3, per 100 parts by weight of the monomer
000 parts by weight of a polymerized toner.