JP2001042564A - Toner and image forming method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the toner and the image forming method each capable of preventing occurrence of image defect due to offset phenomenon at the time of using a fixing device corresponding to energy economy. SOLUTION: This toner is obtained by melting fine resin particles containing a crystalline substance and an amorphous polymer and atatching to each other in an aqueous medium, and this crystal substance is characterized by having an endothermic peak (P1) of 50 deg.C to 130 deg.C in the first temperature rising course in the differential scanning calorimetry (DSC) and an exothermic peak (P2) of 30 deg.C to 110 deg.C in the first temperature lowering course in the DSC and satisfying P1>=P2. The image forming method in this invention includes a process for fixing a toner image with thin heating rollers and the above toner comprises the binder resin containing the above crystalline substance and the above amorphous polymer and a colorant.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a toner and an image forming method.

[0002]

2. Description of the Related Art In recent years, various attempts have been made to reduce fixing energy as a measure for saving energy in a heat roll fixing system. Here, as a measure for reducing the fixing energy, various attempts have been made to reduce the amount of heat (heat capacity) held by the heating roller itself, thereby shortening the time until heat storage and improving the heat transfer efficiency. I have. Specifically, thinning the core metal of the heating roller is used as a preferable measure as a measure of low heat capacity without requiring a large amount of heat. When a heating roller having a thin cored bar is used, the temperature of the roller surface is significantly reduced due to the passage of paper due to its low heat capacity. For this reason, it is necessary to keep the roller surface at a constant temperature by replenishing the heat taken by the paper passing by continuously heating the heating member.
However, if the heating from the heating member is continuously performed,
When narrow paper is passed in the paper passing direction, the temperature of an end region of the roller surface where the narrow paper does not contact becomes excessively high. If wide paper is passed in this state, a high-temperature-side offset phenomenon is likely to occur in the overheated end region, which tends to cause a problem of image contamination. On the other hand, a heating roller having a thin core has a large temperature change, and a toner used in a fixing device having such a heating roller has good adhesiveness (fixing property) to an image support in a wide temperature range. Is required.

[0003]

SUMMARY OF THE INVENTION The present invention has been made based on the above circumstances, and an object of the present invention is to provide:
An object of the present invention is to provide a toner that includes a heating roller having a thin cored bar and does not cause image defects due to an offset phenomenon even when used in a fixing device that meets the demand for energy saving. Another object of the present invention is to provide a method in which the paper passing between a heating roller having a thin metal core and a pressure roller is changed from a narrow one to a wide one, and the end of the wide paper is changed. An object of the present invention is to provide a toner which does not cause an image defect due to an offset phenomenon in a portion. Another object of the present invention is to provide a toner having a wide fixable temperature range, a small change in fixability due to a change in temperature, and exhibiting good fixability in a wide temperature range. Another object of the present invention is to provide an image forming method that includes a fixing step in response to a demand for energy saving and that does not cause image defects due to an offset phenomenon.

[0004]

Means for Solving the Problems In order to achieve the above object, the present inventors have conducted intensive studies and as a result, as a resin component constituting a toner, a crystalline material (a linear material having a specific thermal characteristic) has been developed. The present inventors have found that an excellent anti-offset effect and fixing performance can be obtained by including the amorphous compound) together with an amorphous polymer, and the present invention has been completed based on such findings.

That is, the toner of the present invention is obtained by fusing resin fine particles containing a crystalline substance and an amorphous polymer in an aqueous medium, and the crystalline substance is first heated by DSC. Endothermic peak (P1) during the process is 50 to 130 ° C
Wherein the exothermic peak (P2) in the first cooling process by the DSC is in the range of 30 to 110 ° C., and P1 ≧ P2 is satisfied.

According to the image forming method of the present invention, an electrostatic latent image formed on a photosensitive member is developed with a developer containing toner, and the toner image formed on the photosensitive member is transferred to an image forming support. In the image forming method including a step of fixing the transferred toner image by a fixing device, the fixing device includes a heating roller and a pressure roller that contacts the heating roller, and the heating roller is formed of aluminum, iron, or the like. And a metal or alloy selected from copper and having an inner diameter of 10 to 50 mm and a thickness of 0.1 to 2 mm is coated with a fluororesin on the surface of a metal core, and includes a fixedly arranged heating member. The pressure roller is formed by coating a surface of a core metal with a silicone rubber having an Asker C hardness of 35 to 75 at a thickness of 1 to 30 mm, and the pressure roller and the heating roller The toner includes a binder resin containing a crystalline substance and an amorphous polymer, and a colorant, and the crystalline substance is a first ascendant by DSC. Endothermic peak during temperature process (P
1) is at 50 to 130 ° C, the exothermic peak (P2) in the first cooling step by DSC is at 30 to 110 ° C,
The toner is characterized by satisfying P1 ≧ P2.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. <Fixing Device> The toner of the present invention uses an image forming method including a fixing step using a specific fixing device (the image forming method of the present invention).
It is preferably used. FIG. 1 is a cross-sectional view illustrating an example of a fixing device used in the present invention. The fixing device illustrated in FIG. 1 includes a heating roller 10 and a pressure roller 20 that contacts the heating roller 10. In FIG. 1, T is a toner image formed on transfer paper.

[0008] The heating roller 10 is formed by forming a coating layer 12 made of a fluororesin on the surface of a metal core 11 and includes a heating member 13 made of a linear heater.

The metal core 11 is made of a metal selected from aluminum, iron and copper or an alloy thereof.
Its inner diameter is 10 to 50 mm. The thickness of the core metal 11 is set to 0.1 to 2 mm, and demand for energy saving (thinning)
And strength (depending on the constituent materials). For example, in order to ensure the same strength as a 0.57 mm iron core with an aluminum core, the wall thickness must be 0.8 mm.

As the fluorine resin constituting the coating layer 12, PTFE (polytetrafluoroethylene) and PF
A (tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer) and the like.
The thickness of the coating layer 12 is 50 to 1000 μm.

As the heating member 13, a halogen heater can be suitably used. In addition, not only one heating member but also a configuration in which a plurality of heating members are included and the heat distribution area can be changed according to the size (width) of the passing paper as shown in FIG. . The heating roller 15 shown in FIG. 2 is provided with a halogen heater 16A for heating a central region of the roller surface, and halogen heaters 16B and 16C for heating end regions of the roller surface. . According to the heating roller 15 as shown in FIG. 2, when passing narrow paper, only the halogen heater 16A is energized, and when passing wide paper, the gen heater 16B and the halogen heater 16C are further supplied. It is only necessary to energize.

The pressure roller 20 is formed by forming a coating layer 22 made of silicone rubber on the surface of a metal core 21. The core 21 is made of a metal such as aluminum or iron or an alloy thereof. The thickness of the coating layer 22 is 1 to 30
mm. The Asker C hardness of the silicone rubber constituting the coating layer 22 is 35 to 75, preferably 40 to 50, and may be silicone sponge rubber.

The contact load (total load) between the heating roller 10 and the pressure roller 20 is usually 4 to 35 kgf, preferably 5 to 30 kgf, more preferably 5 to 30 kgf.
It is 25 kgf. This contact load is applied to the heating roller 1
It is defined in consideration of the strength of 0 (thickness of the metal core 11). For example, in the case of a heating roller having a metal core of 0.3 mm, it is preferably 25 kgf or less.

From the viewpoints of offset resistance and fixability,
The nip width is preferably 4 to 8 mm, and the surface pressure of the nip is preferably 0.6 to 1.5 kgf / cm ² .

As an example of fixing conditions by the fixing device as shown in FIG. 1, the fixing temperature (surface temperature of the heating roller 10) is set to 150 to 210 ° C., and the fixing linear speed is set to 80 to 6
40 mm / sec.

The fixing device used in the present invention may be provided with a fixing unit cleaning mechanism as required. In this case, as a method of supplying the silicone oil to the upper roller of the fixing unit, a method of supplying and cleaning with a pad, a roller, a web, or the like impregnated with the silicone oil can be used. High heat-resistant silicone oils are used, such as polydimethyl silicone,
Polyphenylmethyl silicone, polydiphenyl silicone and the like are used. Since those having low viscosity have a large outflow during use, the viscosity at 20 ° C.
Those having 0 to 100,000 cp are preferably used. In particular, the present invention is remarkably effective in a system using a fixed amount of silicone oil. The reason is that since silicone oil is insulative, the heating roller where the oil is present on the surface has more charge accumulation due to frictional charging due to friction due to rotation with the pressure roller,
As a result, repelling tends to occur, but this is effectively prevented by the present invention. The amount of silicone oil applied is preferably 0.1 to 10 μg / cm ² .

Further, in order to suppress overheating of the end area on the roller surface, the fixing device may be provided with a cooling fan or the like for the end area.

<Construction of Toner> The toner of the present invention is produced by fusing resin fine particles containing a crystalline substance and an amorphous polymer in an aqueous medium. As a method for fusing resin fine particles in an aqueous medium, for example,
JP-186253, JP-63-282749A,
Examples of the method include a method described in JP-A-7-146583. Further, as a particularly preferred fusion method, a method of salting out / fusing resin fine particles in an aqueous medium is particularly preferred. In the present invention, “salting out / fusion” means that salting out (aggregation of fine particles) and fusion (loss of interface between fine particles) occur simultaneously, or an act of causing salting out and fusion simultaneously. Say. In order to carry out salting out and fusion simultaneously, the glass transition temperature (T
g) Fine particles (resin fine particles, colorant fine particles) need to be aggregated under the above temperature conditions. The weight average particle size of the resin fine particles used to obtain the toner of the present invention is 5
0-2000 nm is preferred. Such resin fine particles may be obtained by any granulation polymerization method such as an emulsion polymerization method, a suspension polymerization method, and a seed polymerization method, but are preferably resin fine particles obtained by an emulsion polymerization method.

<Crystalline Substance> The toner of the present invention and the toner used in the image forming method of the present invention (hereinafter also referred to as “toner of the present invention”) have specific thermal characteristics as a resin component. Contains crystalline material.

[Physical Properties of Crystalline Substance] The crystalline substance constituting the toner according to the present invention has an endothermic peak (P1) in the first temperature raising step by DSC at 50 to 130 ° C., preferably 60 to 130 ° C. At 120 ° C. In addition, the crystalline substance has an exothermic peak (P) during the first cooling process by DSC.
2) is at 30 to 110 ° C, preferably 40 to 120
° C. Here, the relationship of P1 ≧ P2 is established between the endothermic peak (P1) and the exothermic peak (P2). Although the temperature difference (P1-P2) is not particularly limited,
It is preferably 0 ° C. or lower.

By including a crystalline substance having the above-mentioned thermal characteristics as a resin component of the toner, an excellent offset prevention effect (wide fixing temperature range) can be obtained, as is apparent from the results of Examples described later. ) And excellent fixability (high fixation rate). In order to exhibit the effects of the present invention, it is preferable that the amorphous polymer and the crystalline substance exist independently of each other. That is, the crystalline substance dissolves sharply, and the action of dissolving the amorphous polymer in the melted state acts. As a result, the melt viscosity of the entire toner can be reduced, and the fixability can be improved. is there. In addition, since they are present independently of each other, it is possible to suppress a decrease in the elastic modulus on the high temperature side, so that the offset resistance is not impaired.

When the endothermic peak (P1) is below 50 ° C., the fixing temperature is improved due to the low melting temperature, but the offset resistance and the storage stability are reduced.
When the endothermic peak (P1) exists in a range exceeding 130 ° C., the melting temperature is high, so that the melting temperature with the amorphous polymer becomes high, and as a result, the fixability cannot be improved. .

Exothermic peak (P2) indicating the state of recrystallization
If it is below 30 ° C., it cannot be recrystallized without cooling to a much lower temperature, and such a substance will be present in the toner with low crystallinity, and the Cannot contribute to the improvement of If the heat generation peak (P2) is in a range exceeding 110 ° C., the recrystallization temperature is too high, and the so-called melting temperature becomes high, and the low-temperature fixability is impaired.

The endothermic peak (P1) and the exothermic peak (P
2) is measured by a differential calorimeter (DSC). As the temperature raising / cooling conditions, after leaving at 0 ° C. for 1 minute, the temperature was raised to 200 ° C. at a rate of 10 ° C./min, and the temperature showing the maximum endothermic peak measured at that time is defined as P1. Then, after leaving at 200 ° C. for 1 minute, 10 ° C./mi
The temperature falls under the condition of n, and the temperature at which the maximum exothermic peak is measured is defined as P2. Specific examples of the measuring device include DSC-7 manufactured by PerkinElmer.

The number average molecular weight of the crystalline substance is from 1,500 to
It is preferably 15,000, and more preferably 2,000 to 10,000. 1,500-1
According to the crystalline substance having a number average molecular weight in the range of 5,000, in the obtained toner, the compatibility in a molten state with an amorphous polymer for exhibiting a decrease in the overall melt viscosity is improved, Fixability at lower temperatures is improved.
When the number average molecular weight is less than 1,500, the melt viscosity of the crystalline substance becomes excessively low, and the compatibility state tends to be nonuniform, and it is difficult to improve the fixing property. On the other hand, when the number average molecular weight exceeds 15,000, it takes a long time to melt the crystalline substance, and even in this case, the compatibility state becomes nonuniform, so that the effect of improving the fixing property is reduced. Here, the number average molecular weight of the crystalline substance means a value obtained from the molecular weight measured according to the following conditions.

(Conditions) Model used: "LC-6A" (manufactured by Shimadzu Corporation) Column: "Ultra Styra Gel Plus" Analysis temperature: 60 ° C. Solvent: = m-cresol / chlorobenzene = 3
/ 1 (volume ratio) • Calibration curve: Standard polystyrene calibration curve

[Compound Constituting Crystalline Substance] Examples of compounds composing the crystalline substance include polyesters, polyamides, and polyimides. Aliphatic diols and aliphatic dicarboxylic acids (acid anhydrides and acid chlorides) ), And aliphatic polyamides obtained by reacting an aliphatic polyester, an aliphatic diamine, and an aliphatic dicarboxylic acid (including an acid anhydride and an acid chloride). Is particularly preferred. Here, the dicarboxylic acid and diol used for preparing the crystalline substance preferably have no branched chain (having a skeleton having 1 or more carbon atoms such as an alkyl group from the skeleton of the main chain).

The diol used to obtain the crystalline polyester includes ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol,
4-butanediol, 1,4, butenediol, neopentyl glycol, 1,5-pentanediol, 1,
6-hexanediol, decanediol, hexadecanediol, dodecanediol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol,
Dipropylene glycol, polyethylene glycol,
Examples thereof include polypropylene glycol and polytetramethylene glycol.

The diamine used to obtain the crystalline polyamide includes ethylene diamine, diethylene diamine, triethylene diamine, 1,2-propylene diamine, 1,3-propylene diamine, 1,4-butane diamine, 1,4 -Butenediamine, 2,2-dimethyl-1,3-butanediamine, 1,5-pentanediamine, 1,6-hexanediamine, 1,4-cyclohexanediamine, 1,4-cyclohexanedimethylamine and the like. it can.

The dicarboxylic acids used to obtain crystalline polyesters and crystalline polyamides include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid,
Pimelic acid, spearic acid, azelaic acid, sebacic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutacoic acid, n-dodecylsuccinic acid, n-dodecenylsuccinic acid, isododecylsuccinic acid, isododecenylsuccinic acid Acids, n-octylsuccinic acid, n-octenylsuccinic acid, and acid anhydrides or acid chlorides thereof can be mentioned.

As a method for preparing the aliphatic polyester, there is also a method for preparing the polyester by ring-opening polymerization of various lactones, in addition to the condensation of the aliphatic dicarboxylic acid and the aliphatic diol. In this case, as the lactone, δ-valerolactone,
ε-caprolactone, β-propiolactone and the like can be exemplified. Particularly preferred crystalline materials include
Polyester obtained by reacting cyclohexanediol and adipic acid; polyester obtained by reacting 1,6 hexanediol and sebacic acid; polyester obtained by reacting ethylene glycol and succinic acid; ethylene glycol and sebacic acid And polyester obtained by reacting 1,4-butanediol and succinic acid. Of these, polyester obtained by reacting cyclohexanediol and adipic acid is preferred. Most preferred.

<Amorphous Polymer> [Physical Properties of Amorphous Polymer] The glass transition temperature (T) of the amorphous polymer (amorphous vinyl polymer) contained in the resin fine particles
g) is preferably in the range of 10 to 75 ° C, more preferably 40 to 65 ° C. The softening point of the amorphous polymer is preferably in the range of 80 to 220 ° C.
The molecular weight of the amorphous polymer is determined by the weight average molecular weight (M
In w), it is preferably 5,000 to 1,000,000, more preferably 8,000 to 500,000, and the number average molecular weight (Mn) is 2,000 to 200,0.
00 is preferred. In addition, the molecular weight distribution (Mw /
Mn) is preferably from 2.0 to 100, and more preferably from 5.0 to 80.

Here, the softening point of the amorphous polymer is a value measured using a Koka type flow tester (manufactured by Shimadzu Corporation). Specifically, the Koka type flow tester “CFT
-500 "(manufactured by Shimadzu Corporation), when a sample of 1 cm ³ is melted and flown out under the conditions of a diameter of a pore of a die of 1 mm, a length of 1 mm, a load of 20 kg / cm ² and a heating rate of 6 ° C./min. The temperature corresponding to one half of the height from the outflow start point to the outflow end point is shown as the softening point.

The glass transition point of the amorphous polymer is D
The intersection between the baseline and the slope of the endothermic peak is determined as the glass transition point by the value measured by SC. Specifically, using a differential scanning calorimeter, the temperature was raised to 100 ° C., and
After being left for a minimum of 10 minutes, it is cooled to room temperature at a temperature drop of 10 ° C./min. Then, the sample was heated at a rate of 10 ° C /
When measured in min, the intersection of the extension line of the base line below the glass transition point and the tangent line indicating the maximum slope from the peak rising portion to the peak apex is shown as the glass transition point. As a measuring device, DSC-7 manufactured by Perkin-Elmer can be used.

The molecular weight of the amorphous polymer is a molecular weight in terms of styrene measured by GPC. The method of measuring the molecular weight of a resin by GPC is measurement by GPC (gel permeation chromatography) using THF as a solvent.
That is, the measurement sample is 0.5 to 5 mg, more specifically, 1
1 cc of THF is added to each mg, and the mixture is stirred at room temperature using a magnetic stirrer or the like to be sufficiently dissolved. Then, after treating with a membrane filter having a pore size of 0.45 to 0.50 μm, the mixture is injected into GPC.
GPC measurement conditions were as follows: stabilize the column at 40 ° C,
THF is flowed at a flow rate of 1 cc / min, and about 100 μl of a sample having a concentration of 1 mg / cc is injected to measure. The column is preferably used in combination with a commercially available polystyrene gel column. For example, Shodex manufactured by Showa Denko KK
GPC KF-801,802,803,804,8
05,806,807 and TSK manufactured by Tosoh Corporation
gelG1000H, G2000H, G3000H, G
4000H, G5000H, G6000H, G7000
H, a combination of TSKguardcolumn and the like. Further, a refractive index detector (IR detector) or a UV detector may be used as the detector.
In measuring the molecular weight of a sample, the molecular weight distribution of the sample is calculated using a calibration curve created using monodispersed polystyrene standard particles. 1 for polystyrene for calibration curve creation
It is good to use about 0 points.

[Polymer Constituting Amorphous Polymer] As the polymerizable monomer used to obtain the amorphous polymer, a radical polymerizable monomer is an essential component, and if necessary, a cross-linkable polymer is used. Agents can be used. Further, it is preferable to contain at least one radical polymerizable monomer having an acidic group or a radical polymerizable monomer having a basic group described below.

(1) Radical polymerizable monomer The radical polymerizable monomer component is not particularly limited, and a conventionally known radical polymerizable monomer can be used. Also, to satisfy the required characteristics,
Species or a combination of two or more can be used. Specifically, aromatic vinyl monomers, (meth) acrylate monomers, vinyl ester monomers,
Vinyl ether monomers, monoolefin monomers, diolefin monomers, halogenated olefin monomers and the like can be used. Examples of the aromatic vinyl monomer include styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, p-methoxystyrene, p-phenylstyrene, p-chlorostyrene, and p-methylstyrene.
Ethylstyrene, pn-butylstyrene, p-ter
t-butylstyrene, pn-hexylstyrene, p-
n-octylstyrene, pn-nonylstyrene, p-
n-decylstyrene, pn-dodecylstyrene, 2,
Styrene-based monomers such as 4-dimethylstyrene and 3,4-dichlorostyrene, and derivatives thereof. Examples of (meth) acrylate monomers include methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, phenyl acrylate, methyl methacrylate, ethyl methacrylate, and methacrylic acid. Butyl, hexyl methacrylate, 2-ethylhexyl methacrylate, ethyl β-hydroxyacrylate, propyl γ-aminoacrylate, stearyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, and the like. Examples of the vinyl ester monomer include vinyl acetate, vinyl propionate, and vinyl benzoate. Examples of the vinyl ether monomer include vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether, vinyl phenyl ether and the like. Monoolefin monomers include ethylene, propylene,
Isobutylene, 1-butene, 1-pentene, 4-methyl-1-pentene and the like. Examples of the diolefin-based monomer include butadiene, isoprene, and chloroprene. As the halogenated olefin monomer,
Vinyl chloride, vinylidene chloride, vinyl bromide and the like.

(2) Crosslinking Agent As the crosslinking agent, a radical polymerizable crosslinking agent may be added in order to improve the properties of the toner. Examples of the radical polymerizable crosslinking agent include divinylbenzene, divinylnaphthalene,
Examples thereof include those having two or more unsaturated bonds such as divinyl ether, diethylene glycol methacrylate, ethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, and diallyl phthalate.

(3) Radical polymerizable monomer having an acidic group or radical polymerizable monomer having a basic group Radical polymerizable monomer having an acidic group or radical polymerizable monomer having a basic group For example, an amine compound such as a carboxyl group-containing monomer, a sulfonic acid group-containing monomer, a primary amine, a secondary amine, a tertiary amine, and a quaternary ammonium salt may be used. it can. As the radical polymerizable monomer having an acidic group, as a carboxylic acid group-containing monomer, acrylic acid, methacrylic acid, fumaric acid, maleic acid, itaconic acid, cinnamic acid, maleic acid monobutyl ester, maleic acid monomer Octyl ester and the like. Examples of the sulfonic acid group-containing monomer include styrene sulfonic acid, allyl sulfosuccinic acid, octyl allyl sulfosuccinate, and the like. They are,
The structure may be an alkali metal salt such as sodium or potassium or an alkaline earth metal salt such as calcium.

Examples of the radical polymerizable monomer having a basic group include amine compounds, such as dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, diethylaminoethyl acrylate, diethylaminoethyl methacrylate, and quaternary of the above four compounds. Ammonium salt, 3-dimethylaminophenyl acrylate, 2-hydroxy-3-methacryloxypropyltrimethylammonium salt, acrylamide, N-butylacrylamide, N, N-dibutylacrylamide,
Piperidylacrylamide, methacrylamide, N-butylmethacrylamide, N-octadecylacrylamide; vinylpyridine, vinylpyrrolidone; vinyl N-methylpyridinium chloride, vinyl N-ethylpyridinium chloride, N, N-diallylmethylammonium chloride, N, N- Diallylethylammonium chloride and the like can be mentioned.

As the radical polymerizable monomer used in the present invention, a radical polymerizable monomer having an acidic group or a radical polymerizable monomer having a basic group is contained in an amount of 0.1 to 15% of the whole monomer. Preferably, the radical polymerizable cross-linking agent is used in the range of 0.1 to 10% by weight, based on the total radical polymerizable monomer, depending on its properties.

[Chain transfer agent] For the purpose of adjusting the molecular weight of the amorphous polymer, a chain transfer agent generally used can be used. The chain transfer agent is not particularly limited, and for example, mercaptans such as octyl mercaptan, dodecyl mercaptan, tert-dodecyl mercaptan, and styrene dimer are used.

[Polymerization Initiator] The radical polymerization initiator used in the present invention can be appropriately used as long as it is water-soluble.
For example, persulfates (potassium persulfate, ammonium persulfate, etc.), azo compounds (4,4'-azobis-4-cyanovaleric acid and its salts, 2,2'-azobis (2-amidinopropane) salts, etc.), peroxides And the like.
Further, the radical polymerization initiator can be used as a redox initiator in combination with a reducing agent, if necessary. By using a redox-based initiator, the polymerization activity is increased, the polymerization temperature can be reduced, and a further reduction in the polymerization time can be expected. As the polymerization temperature, any temperature may be selected as long as it is equal to or higher than the minimum radical generation temperature of the polymerization initiator.
To 90 ° C. However, by using a polymerization initiator started at room temperature, for example, a combination of hydrogen peroxide and a reducing agent (such as ascorbic acid), polymerization can be performed at room temperature or higher.

In the present invention, a crystalline substance is dissolved in the above-mentioned radically polymerizable monomer to prepare a radically polymerizable monomer solution of the crystalline substance. It is preferable to carry out polymerization after emulsifying or suspending in water using a dispersant. The specific method of the polymerization treatment will be described later.

[Surfactant] In order to carry out emulsion polymerization using the above-mentioned radically polymerizable monomer, it is necessary to carry out emulsion polymerization using a surfactant. The surfactant that can be used at this time is not particularly limited, but the following ionic surfactants can be mentioned as preferred examples. Examples of the ionic surfactant include sulfonates (sodium dodecylbenzenesulfonate, sodium arylalkylpolyethersulfonate, 3,3-disulfondiphenylurea-4,4-diazo-bis-amino-8-naphthol-6). Sodium sulfonate, ortho-carboxybenzene-azo-dimethylaniline, sodium 2,2,5,5-tetramethyl-triphenylmethane-4,4-diazo-bis-β-naphthol-6-sulfonate), sulfuric acid Ester salts (sodium dodecyl sulfate, sodium tetradecyl sulfate,
Sodium pentadecyl sulfate, sodium octyl sulfate, etc.) and fatty acid salts (sodium oleate, sodium laurate, sodium caprate, sodium caprylate, sodium caproate, potassium stearate, calcium oleate, etc.). Further, a nonionic surfactant can also be used. Specifically, polyethylene oxide, polypropylene oxide, a combination of polypropylene oxide and polyethylene oxide, esters of polyethylene glycol and higher fatty acids, alkylphenol polyethylene oxide,
Esters of higher fatty acids and polyethylene glycol, esters of higher fatty acids and polypropylene oxide, sorbitan esters and the like can be mentioned. In the present invention, these are mainly used as emulsifiers at the time of emulsion polymerization, but may be used for other steps or purposes.

<Content Ratio of Crystalline Substance and Amorphous Polymer> The content ratio of the crystalline substance and the amorphous polymer in the fine resin particles is determined based on 100 parts by weight of the amorphous polymer and the crystalline substance. Is preferably 1 to 200 parts by weight, more preferably 2 to 100 parts by weight, particularly preferably 3 to 50 parts by weight. When the proportion of the crystalline substance is too small, the obtained toner does not have sufficient fixability. On the other hand, if this percentage is too high,
Excessive melting due to the presence of an excessive amount of a crystalline substance proceeds, and the melt viscosity is reduced, so that there is a problem that offset is likely to occur.

<Colorant> Examples of the colorant constituting the toner of the present invention include inorganic pigments and organic pigments.
Conventionally known inorganic pigments can be used. Specific inorganic pigments are exemplified below. As the black pigment, for example, carbon black such as furnace black, channel black, acetylene black, thermal black and lamp black, and magnetic powder such as magnetite and ferrite are also used. These inorganic pigments can be used alone or in combination of two or more as desired. The amount of the pigment to be added is 2 to 20% by weight, preferably 3 to 15% by weight, based on the polymer. When used as a magnetic toner, the above-mentioned magnetite can be added. In this case, from the viewpoint of imparting predetermined magnetic properties, it is preferable to add 20 to 60% by weight to the toner. Conventionally known organic pigments can also be used. Specific organic pigments are exemplified below. Pigments for magenta or red include C.I. I.
Pigment Red 2, C.I. I. Pigment Red 3,
C. I. Pigment Red 5, C.I. I. Pigment Red 6, C.I. I. Pigment Red 7, C.I. I. Pigment Red 15, C.I. I. Pigment Red 16, C.I.
I. Pigment Red 48: 1, C.I. I. Pigment Red 53: 1, C.I. I. Pigment Red 57: 1,
C. I. Pigment Red 122, C.I. I. Pigment Red 123, C.I. I. Pigment Red 139, C.I.
I. Pigment red 144, C.I. I. Pigment Red 149, C.I. I. Pigment Red 166, C.I. I.
Pigment Red 177, C.I. I. Pigment Red 1
78, C.I. I. Pigment Red 222 and the like. Examples of orange or yellow pigments include C.I.
I. Pigment Orange 31, C.I. I. Pigment Orange 43, C.I. I. Pigment Yellow 12, C.I. I.
Pigment Yellow 13, C.I. I. Pigment Yellow 14, C.I. I. Pigment Yellow 15, C.I. I. Pigment Yellow 17, C.I. I. Pigment Yellow 9
3, C.I. I. Pigment Yellow 94, C.I. I. Pigment Yellow 138 and the like. Green or cyan pigments include C.I. I. Pigment Blue 1
5, C.I. I. Pigment Blue 15: 2, C.I. I. Pigment Blue 15: 3, C.I. I. Pigment Blue 1
6, C.I. I. Pigment Blue 60, C.I. I. Pigment Green 7 and the like. These organic pigments can be used alone or in combination of two or more as desired. The amount of the pigment added is 2 to 20% by weight based on the weight of the polymer.
And preferably 3 to 15% by weight.

The colorant can be used after surface modification. As the surface modifier, a conventionally known one can be used, and specifically, a silane coupling agent, a titanium coupling agent, an aluminum coupling agent and the like can be preferably used.

<External additives> The toner of the present invention has fluidity,
A so-called external additive can be added and used for the purpose of improving the charging property and the cleaning property.
These external additives are not particularly limited, and various inorganic fine particles, organic fine particles, and lubricants can be used. Conventionally known inorganic fine particles can be used. Specifically, silica, titanium, alumina fine particles and the like can be preferably used. These inorganic fine particles are preferably hydrophobic. In particular,
As silica fine particles, for example, commercially available products manufactured by Nippon Aerosil Co., Ltd. R-805, R-976, R-974, R-972,
R-812, R-809, HVK-21 manufactured by Hoechst
50, H-200, commercially available TS-72 manufactured by Cabot Corporation
0, TS-530, TS-610, H-5, MS-5 and the like. As the titanium fine particles, for example, commercially available products T-805 and T-604 manufactured by Nippon Aerosil Co., Ltd., and commercially available products MT-100S, MT-100B and MT- manufactured by Teika Co., Ltd.
500BS, MT-600, MT-600SS, JA-
1. Commercial products TA-300SI, TA-
500, TAF-130, TAF-510, TAF-5
10T, commercial products IT-S, IT-OA manufactured by Idemitsu Kosan Co., Ltd.
IT-OB, IT-OC and the like can be mentioned. As the alumina fine particles, for example, a commercial product RF manufactured by Nippon Aerosil Co., Ltd.
YC, C-604, commercial product TTO-5 manufactured by Ishihara Sangyo Co., Ltd.
5 and the like. Further, as the organic fine particles, spherical organic fine particles having a number average primary particle diameter of about 10 to 2000 nm can be used. As this, a homopolymer such as styrene or methyl methacrylate or a copolymer thereof can be used. Lubricants include, for example, salts of stearic acid zinc, aluminum, copper, magnesium, calcium, etc., oleic acid zinc, manganese, iron,
Metal salts of higher fatty acids such as salts of copper, magnesium and the like, salts of zinc, copper, magnesium and calcium of palmitic acid, salts of zinc and calcium of linoleic acid, and salts of zinc and calcium of ricinoleic acid. . The addition amount of these external additives is preferably about 0.1 to 5% by weight based on the toner.

<Manufacturing Process of Toner> As one example of the manufacturing method of the present invention, (1) a dissolving process in which a crystalline substance is dissolved in a radical polymerizable monomer, and (2) a dispersion of resin fine particles is prepared. (3) a fusion step of fusing resin fine particles in an aqueous medium to obtain toner particles (associated particles);
(4) a filtration / washing step of filtering the toner particles from the dispersion liquid of the toner particles to remove a surfactant or the like from the toner particles, and (5) a drying step of drying the washed toner particles. (6) A step of adding an external additive to the dried toner particles may be included.

Hereinafter, each step will be described. [Dissolving Step] In this step, a crystalline substance is dissolved in a radical polymerizable monomer to prepare a radical polymerizable monomer solution of the crystalline substance. The use ratio of the crystalline substance is 1 to 100 parts by weight of the radical polymerizable monomer.
Preferably it is 200 parts by weight, more preferably 2 parts by weight.
To 100 parts by weight, particularly preferably 3 to 50 parts by weight.

[Polymerization Step] In a preferred example of this polymerization step, a droplet of the radical polymerizable monomer solution of the crystalline substance is placed in an aqueous medium (aqueous solution of a surfactant and a radical polymerization initiator). The polymerization reaction proceeds in the droplet by the radical from the radical polymerization initiator. Incidentally, an oil-soluble polymerization initiator may be contained in the droplet. In such a polymerization process, mechanical energy is applied to forcibly emulsify (form droplets).
Processing is required. Examples of the means for applying mechanical energy include means for applying strong stirring or ultrasonic vibration energy such as a homomixer, ultrasonic waves, and Manton-Gaulin.

By this polymerization step, resin fine particles containing a crystalline substance and an amorphous polymer can be obtained. Such resin fine particles may be colored fine particles or non-colored fine particles. The colored resin fine particles are obtained by polymerizing a monomer composition containing a colorant. In the case where uncolored resin fine particles are used, in a fusing step described later, a dispersion of colorant fine particles is added to a dispersion of resin fine particles, and the resin fine particles and the colorant fine particles are fused. Thus, toner particles can be obtained.

[Fusing Step] As a method of fusing in the fusing step, a salting out / fusion method using resin fine particles (colored or non-colored resin fine particles) obtained in the polymerization step is preferable. In addition, in the fusing step, not only resin fine particles and colorant fine particles, but also fine particles of an internal additive such as a releasing agent fine particle and a charge control agent can be fused.

The “aqueous medium” in the fusing step is
A substance whose main component (50% by weight or more) is composed of water. Here, examples of the component other than water include an organic solvent soluble in water, such as methanol, ethanol, isopropanol, butanol, acetone, methyl ethyl ketone, and tetrahydrofuran. Of these, methanol, which is an organic solvent that does not dissolve the resin,
Alcohol organic solvents such as ethanol, isopropanol and butanol are particularly preferred.

The coloring agent fine particles can be prepared by dispersing the coloring agent in an aqueous medium. Dispersion treatment of the colorant is carried out by adjusting the surfactant concentration in water to the critical micelle concentration (CM
C) It is performed in the state described above. The dispersing machine used for the dispersion treatment of the colorant is not particularly limited, but is preferably an ultrasonic dispersing machine, a mechanical homogenizer, a pressure dispersing machine such as Manton-Gaulin or a pressure homogenizer, a sand grinder, a Getzman mill or a diamond fine mill. A medium type dispersing machine may be used. Examples of the surfactant used include the same surfactants as described above. Note that the colorant (fine particles) may be surface-modified. In the method for modifying the surface of the colorant, the colorant is dispersed in a solvent, the surface modifier is added to the molecular weight liquid, and the system is reacted by raising the temperature. After completion of the reaction, the colorant is separated by filtration, washed and filtered repeatedly with the same solvent, and then dried to obtain a colorant (pigment) treated with the surface modifier.

The salting-out / fusing method, which is a preferred fusing method, is as follows:
In a water in which resin fine particles and colorant fine particles are present, a salting-out agent composed of an alkali metal salt, an alkaline earth metal salt, or the like is added as a coagulant having a critical coagulation concentration or more, and then the glass transition of the resin fine particles is performed. This is a step in which the salting-out is advanced by heating to more than the point, and at the same time, the fusion is performed. In this step, a method may be employed in which an organic solvent that is infinitely soluble in water is added, and the glass transition temperature of the resin fine particles is substantially lowered to effectively perform fusion. Here, the alkali metal salt and the alkaline earth metal salt that are salting-out agents include lithium, potassium, and sodium as the alkali metal,
As alkaline earth metals, magnesium, calcium,
Strontium, barium and the like can be mentioned, and preferably potassium, sodium, magnesium, calcium and barium can be mentioned. Also, as a constituent of the salt,
Chloride, bromide, iodine, carbonate, sulfate and the like can be mentioned. Further, as the organic solvent infinitely soluble in water,
Methanol, ethanol, 1-propanol, 2-propanol, ethylene glycol, glycerin, acetone and the like can be mentioned. Alcohols of methanol, ethanol, 1-propanol and 2-propanol having 3 or less carbon atoms are preferable, and especially, 2- Propanol is preferred.

When the fusion of the present invention is carried out by salting out / fusing, it is preferable to minimize the time of standing after adding the salting out agent. Although the reason for this is not clear, the aggregation state of the particles fluctuates depending on the standing time after salting out,
There are problems that the particle size distribution becomes unstable and the surface properties of the fused toner fluctuate. Further, the temperature at which the salting-out agent is added needs to be at least equal to or lower than the glass transition temperature of the resin fine particles. This is because
If the temperature at which the salting-out agent is added is equal to or higher than the glass transition temperature of the resin fine particles, the salting-out / fusion of the resin fine particles proceeds rapidly, but the particle size cannot be controlled, and the particles having a large particle size cannot be controlled. Problems that occur. The range of the addition temperature may be lower than the glass transition temperature of the resin, but is generally 5 to 55 ° C, preferably 10 to 45 ° C.
In the present invention, it is preferable to use a method in which a salting-out agent is added at a temperature equal to or lower than the glass transition temperature of the resin fine particles, and thereafter, the temperature is raised as quickly as possible, and the temperature is raised to a temperature equal to or higher than the glass transition temperature of the resin fine particles. The time until the temperature rise is preferably less than 1 hour. Further, it is necessary to raise the temperature promptly, but the rate of temperature increase is preferably 0.25 ° C./min or more. The upper limit is not particularly clear, but if the temperature is raised instantaneously, salting out proceeds rapidly, and there is a problem that particle size control is difficult to perform.

[Filtration / Washing Step] In this filtration / washing step, a filtration treatment for filtering the toner particles from the dispersion liquid of the toner particles obtained in the above step and a filtration treatment for the toner particles (cake-like) are performed. Washing treatment for removing extraneous substances such as surfactants and salting-out agents from the aggregates). Here, the filtration method is not particularly limited, such as a centrifugal separation method, a reduced pressure filtration method using a Nutsche method, a filtration method using a filter press, or the like.

[Drying Step] This step is a step of drying the washed toner particles. Dryers used in this step include spray dryers, vacuum freeze dryers, vacuum dryers and the like, stationary shelf dryers, mobile shelf dryers, fluidized bed dryers, rotary dryers ,
It is preferable to use a stirring dryer or the like. The moisture content of the dried toner particles is preferably 5% by weight or less, more preferably 2% by weight or less. In the case where the dried toner particles are aggregated by a weak attractive force between the particles, the aggregate may be crushed. Here, jet mill,
A mechanical crushing device such as a Henschel mixer, a coffee mill, a food processor and the like can be used.

[Step of Adding External Additive] This step is a step of adding an external additive to the dried toner particles. Examples of a device used for adding the external additive include various known mixing devices such as a turbular mixer, a Hensiel mixer, a Nauter mixer, and a V-type mixer.

The toner may contain a material capable of imparting various functions as a toner material in addition to the colorant and the release agent. Specific examples include a charge control agent. These components are added at the stage of polymerizing the resin fine particles, the dispersion is added, the resin fine particles and the colorant particles are added at the same time in the salting-out / fusion step, and included in the toner. It can be added by various methods such as an adding method. As a preferable method, a method in which the charge control agent particles and / or the release agent particles are added in a dispersion state at the stage of polymerizing the resin fine particles, and the resin fine particles and the colorant particles in the salting out / fusing step are used. At the same time, charge control agent particles and / or release agent particles are added in the form of a dispersion, and salting out /
A method of fusing is exemplified. As the release agent, it is preferable to use various known ones which can be dispersed in water. Specific examples include olefin waxes such as polypropylene and polyethylene, modified products thereof, natural waxes such as carnauba wax and rice wax, and amide waxes such as fatty acid bisamide. These are added as release agent particles and can be salted out / fused together with the resin and colorant. Similarly, various known charge control agents, which can be dispersed in water, can be used. Specific examples include a nigrosine dye, a metal salt of naphthenic acid or a higher fatty acid, an alkoxylated amine, a quaternary ammonium salt compound, an azo metal complex, a metal salt of salicylic acid, and a metal complex thereof. The particles of the release agent and the charge control agent preferably have a number average primary particle diameter of about 10 to 500 nm in a dispersed state.

<Particle Size of Toner> The volume average particle size of the toner of the present invention is preferably from 3 to 9 μm, and more preferably from 4 to 8 μm. Here, the volume average particle size of the toner is a value measured using a Coulter Counter TA-II, a Coulter Multisizer, a SLAD1100 (a laser diffraction particle size measuring device manufactured by Shimadzu Corporation), or the like. In the Coulter Counter TAII and Coulter Multisizer, values measured using an aperture having an aperture diameter of 100 μm and a particle size distribution in the range of 2.0 to 40 μm are shown.

<Developer> The toner of the present invention may be used as a one-component developer or a two-component developer, but is preferably a two-component developer.

When the toner is used as a one-component developer, there is a method of using the toner as it is as a non-magnetic one-component developer. However, usually, the toner particles contain magnetic particles of about 0.1 to 5 μm and a magnetic one-component developer is used. Used as a developer. As a method of containing the same, it is common to make the non-spherical particles contain the same as the coloring agent.

Further, it can be used as a two-component developer by mixing with a carrier. In this case, as the magnetic particles of the carrier, conventionally known materials such as metals such as iron, ferrite and magnetite, and alloys of these metals with metals such as aluminum and lead are used. Particularly, ferrite particles are preferable. The magnetic particles have a volume average particle size of 15
-100 μm, more preferably 25-60 μm.

The volume average particle size of the carrier is typically measured by a laser diffraction type particle size distribution analyzer “HELOS” equipped with a wet disperser (SYMPATIC (SYMPIC)).
(ATEC)).

The carrier is preferably a carrier in which magnetic particles are further coated with a resin, or a so-called resin-dispersed carrier in which magnetic particles are dispersed in a resin. Although there is no particular limitation on the resin composition for coating, for example, an olefin resin, a styrene resin, a styrene / acrylic resin, a silicone resin, an ester resin, a fluorine-containing polymer resin, or the like is used. The resin for forming the resin dispersion type carrier is not particularly limited, and known resins can be used.For example, styrene acrylic resin, polyester resin, fluorine resin, phenol resin, and the like can be used. it can.

[0069]

EXAMPLES The present invention will be described below in detail with reference to examples, but embodiments of the present invention are not limited thereto. In the following, “parts” means “parts by weight”.

[Production Example 1 of Colored Particles] (1) Preparation of Colorant Dispersion: 0.90 kg of sodium n-dodecyl sulfate and 10.0 L of pure water were added and stirred and dissolved. To this liquid, 1.20 kg of Regal 330R (carbon black manufactured by Cabot Corporation) was gradually added under stirring, and then, using a sand grinder (medium type disperser),
The dispersion was continued for 20 hours. After dispersion, the particle diameter of the dispersion was measured using an electrophoretic light scattering photometer ELS-800 manufactured by Otsuka Electronics Co., Ltd., and as a result, the dispersion was 122 nm in weight average diameter. Further, the solid content concentration of the above dispersion measured by a weight method by standing drying was 16.6% by weight. This dispersion is referred to as “colorant dispersion 1”.

(2) Preparation of latex A1: styrene =
567 g, n-butyl acrylate = 98 g, methacrylic acid = 35 g, t-dodecyl mercaptan = 24.1 g
Then, a crystalline substance (crystalline substance 1) shown in the following table 3 was added according to the recipe shown in the following table 1, and the temperature was raised to 85 ° C. with stirring to dissolve the crystalline substance, and a monomer solution (dissolved the crystalline substance) Radical polymerizable monomer solution). Then, a thermometer containing an aqueous solution in which 1 g of sodium dodecylbenzenesulfonate was dissolved in 2700 mL of pure water,
A four-necked flask having a cooling tube and a stirrer was heated to 85 ° C., and the monomer solution was added dropwise under the temperature condition.
While maintaining the temperature at 5 ° C., ultrasonic vibration was applied to completely disperse the monomer solution in an aqueous solution containing a surfactant. Thereafter, the temperature was lowered to 70 ° C., a water-soluble polymerization initiator solution in which 8.3 g of ammonium persulfate was dissolved in 500 mL of pure water was added dropwise, and the mixture was reacted at 70 ° C. for 4 hours under a nitrogen stream. Thereafter, the mixture was cooled and foreign substances were removed with a pole filter to obtain latex A1.

(3) Preparation of latex B1: styrene =
497 g, n-butyl acrylate = 168 g, methacrylic acid = 35 g, t-dodecyl mercaptan = 0.66
g, a crystalline substance (crystalline substance 1) shown in Table 3 below was added according to the recipe shown in Table 1 below, and the temperature was raised to 85 ° C. with stirring to dissolve the crystalline substance. A dissolved radically polymerizable monomer solution) was prepared.
Then, a four-necked flask equipped with a thermometer, a cooling pipe, and a stirrer in which an aqueous solution in which 1.34 g of sodium dodecylbenzenesulfonate was dissolved in 2700 mL of pure water was placed.
The mixture was heated to 5 ° C., the monomer solution was added dropwise at the temperature, and ultrasonic vibration was applied while maintaining the temperature at 85 ° C. to completely disperse the monomer solution in an aqueous solution containing a surfactant. Thereafter, the temperature was lowered to 70 ° C., a water-soluble polymerization initiator solution obtained by dissolving 1.48 g of ammonium persulfate in 500 mL of pure water was added dropwise, and reacted at 70 ° C. for 4 hours under a nitrogen stream. Thereafter, the mixture was cooled and foreign substances were removed with a pole filter to obtain latex B1.

(4) Salting-out / fusion step: 1.07 kg of sodium chloride as a salting-out agent and 5.0 L of ion-exchanged water were added and dissolved by stirring. This is designated as sodium chloride solution A. In a reaction vessel equipped with a temperature sensor, a cooling pipe, a nitrogen introduction device, a stirrer, and a comb baffle, the latex A1 produced above and the latex B1 produced were 5.0 kg and 5.0 k, respectively.
g, colorant dispersion 1 = 0.4 kg and ion-exchanged water 20.
And stirred. Then, the mixture was heated to 35 ° C., and sodium chloride solution A was added. Thereafter, after standing for 5 minutes, the temperature was raised, and the temperature was raised to a liquid temperature of 85 ° C. in 5 minutes (heating rate = 10 ° C./min). The mixture was heated and stirred at a liquid temperature of 85 ° C. ± 2 ° C. for 6 hours to carry out salting out / fusion. Then 3
The mixture was cooled to 0 ° C. or lower and the stirring was stopped. The solution is filtered through a sieve having an opening of 45 μm, and this filtrate is used as an association liquid. Then, using a centrifuge, the wet cake-like colored particles were collected by filtration from the associated liquid. Thereafter, the substrate was washed with ion-exchanged water. The wet cake-like colored particles that had been washed as described above were dried with warm air at 40 ° C. to obtain colored particles. This colored particle is referred to as “colored particle 1”. The colored particles 1 had a volume average particle diameter of 6.3 μm, and the resin had a number average molecular weight of 6,100 and a weight average molecular weight of 53,000.

[Production Examples of Colored Particles 2 to 26] Latex A
1 and latex B1 were prepared in the following Tables 1-2.
Colored particles 2 were prepared in the same manner as in the production of colored particles 1 except that the crystalline substances shown in Table 3 below were used in accordance with the formulation shown in Table 2.
~ Colored particles 26 were obtained.

[0075]

[Table 1]

[0076]

[Table 2]

[0077]

[Table 3]

To each of the colored particles 1 to 26, 1.0% by weight of hydrophobic silica (hydrophobicity = 65, number average primary particle diameter = 12 nm) was added to obtain a toner. These are referred to as “toner 1” to “toner 26”. Each of the toners 1 to 26 and a ferrite carrier coated with a silicone resin and having a volume average particle diameter of 60 μm were mixed to prepare a developer having a toner concentration of 6%. These are referred to as “developer 1” to “developer 26” corresponding to the toner.

<Examples 1 to 31 and Comparative Examples 1 to 9> [Actual photo test] A digital copying machine Konica 7060 manufactured by Konica Corporation using each of the developers 1 to 26 and having a fixing device shown in Tables 5 to 6 below. By carrying out a real-photographing test using, the anti-offset property (presence or absence of occurrence of fixing offset) and the fixing property (halftone fixing rate) were evaluated.
The results are shown in Tables 5 and 6 below. The developing conditions are as shown below.

(Developing conditions) Photoconductor; laminated organic photoconductor DC bias: -500 V Dsd (distance between photoconductor and developing sleeve): 600 μm Developer layer regulation: Magnetic H-Cut method Developer layer Thickness: 700 μm ・ Developing sleeve diameter: 40 mm

As the fixing device, a pressure fixing type heat fixing device was employed. The configuration of the fixing device and the fixing conditions are as follows.

(Fixing Device 1) Tetrafluoroethylene
Perfluoroalkyl vinyl ether copolymer (PF
A) The diameter is 30mmφ and the total width is 310m.
m, cylindrical thickness 2mm with heater built in the center
Of aluminum alloy as upper roller, tetrafluoro
Ethylene-perfluoroalkyl ether copolymer (P
FA) sponge-like silicone rubber coated on the surface
Car C hardness = 48: Thickness 8 mm) Diameter 40
It has a lower roller of mmφ. Nip pressure is 1.1k
g / cm ^Two(Total load = 19.8kgf) and the nip width is
5.8 mm. Using this fixing device, print lines
The speed was set at 250 mm / sec. The fixing device
Polydiphenyl silicone (2
(With a viscosity of 10,000 cp at 0 ° C)
The feeding method of the tub method was used. Fixing temperature is upper roll
And the set temperature of 175 ° C. What
The amount of silicone oil applied is 0.8μg / cm^Two
And This is referred to as “fixing device 1”. Also, the fixing device
As a mechanism for suppressing the rise in the end temperature of
Fans are installed inside the machine to cool both ends of the
Was placed.

[Fixing devices 2 to 8] According to Table 4 below, the thickness of the core of the heating roller, the material of the core, the thickness of the elastic layer of the pressure roller, the hardness (Asker C hardness), and the nip pressure (total load)
Further, fixing devices 2 to 8 having at least one condition of the nip width different from those of the fixing device 1 were prepared.

[0084]

[Table 4]

[Evaluation Method] (1) Presence or absence of fixing offset: After an A4 image having a 5 mm wide solid black band image in the vertical direction with respect to the transport direction is transported and fixed in the longitudinal direction, the image is perpendicular to the transport direction. To 5
Two A4 images each having a solid black band image having a width of mm and an A4 image having a halftone image having a width of 20 mm were conveyed continuously in a lateral direction, and at that time, it was confirmed whether or not image contamination due to fixing offset occurred. Here, the surface temperature of the heating roller was fixed at a center value of 175 ° C.

(2) Halftone fixing rate: The fixing rate of the halftone image when the surface temperature (center value) of the heating roller was fixed at 175 ° C. was measured. The fixation rate was calculated from the image density before and after the fixed image was rubbed with a 1 kg weight wound with a “sarashi cloth” by the following formula.

[0087]

## EQU1 ## Fixing ratio = [(image density after rubbing) / (image density before rubbing)] × 100

[0088]

[Table 5]

[0089]

[Table 6]

[Stationary Storage Test] A static storage test was performed on each of the toners 1 to 26 by the following method.
The results are shown in Tables 7 and 8 below.

(1) Residual amount on the mesh: The toner is placed in a glass cylinder, and a load of 500 g / cm ² is applied from above to the mesh, for 8 hours under an environment of a temperature of 55 ° C. and a relative humidity of 80%. Stored still. Before and after storage, the ratio of the toner remaining on the sieve when sieved with 100 mesh was measured.

(2) Evaluation of Halftone Image: A developer is obtained by mixing the toner after storage with the carrier, and a digital copying machine Ko manufactured by Konica Corporation equipped with a fixing device 4 is provided.
Using Nica 7060 in a high temperature and high humidity environment (temperature 35
After continuously printing an A4 image having a pixel ratio of 5% 100,000 times at a temperature of 85 ° C. and a relative humidity of 85%, a copy image of a halftone image was formed, and the image quality of the copy image was evaluated. The surface temperature (center value) of the heating roller was set at 175 ° C.

[0093]

[Table 7]

[0094]

[Table 8]

[0095]

According to the toner of the present invention, an image defect caused by an offset phenomenon can be generated when used in a fixing device provided with a heating roller having a thin cored bar in response to a demand for energy saving. Absent. According to the toner of the present invention, when the paper passing between the heating roller having the thin cored bar and the pressure roller is changed from a narrow one to a wide one, the end of the wide paper is changed. No image defect due to the offset phenomenon occurs in the portion. ADVANTAGE OF THE INVENTION According to the toner of this invention, the fluctuation | variation of the fixability resulting from a temperature change is small, and a favorable fixability can be exhibited in a wide temperature range. The toner of the present invention has excellent storage stability. The image forming method of the present invention includes a fixing step in response to a demand for energy saving, and does not cause image defects due to an offset phenomenon.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating an example of a fixing device used in the present invention.

FIG. 2 is an explanatory diagram showing an example of a heat distribution pattern of a heating roller constituting a fixing device used in the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Heating roller 11 Core metal 12 Coating layer 13 Heating member 15 Heating roller 16A Halogen heater 16B Halogen heater 16C Halogen heater 20 Pressure roller 21 Core metal 22 Coating layer

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Masafumi Uchida 2970 Ishikawacho, Hachioji-shi, Tokyo Konica Corporation (72) Inventor Tsuyoshi Uchida 2970 Ishikawacho, Hachioji-shi, Tokyo Konica Corporation (72) Inventor Hiroshi Yamazaki 2970 Ishikawacho, Hachioji-shi, Tokyo Konica Corporation F term (reference) 2H005 AA01 AB03 CA04 CA08 DA06 EA03 FB01 2H033 BA58 BB03 BB05 BB13 BB29 BB34

Claims (2)

[Claims] 1. A resin material containing a crystalline substance and an amorphous polymer, which is obtained by fusing in a water-based medium, wherein the crystalline substance has an endothermic peak (first endothermic peak in a first temperature raising process by DSC) P1) is at 50 to 130 ° C., and the exothermic peak (P2) in the first cooling step by DSC is 30 to 11
A toner which is at 0 ° C. and satisfies P1 ≧ P2. 2. An electrostatic latent image formed on a photoreceptor is developed with a developer containing toner, and the toner image formed on the photoreceptor is transferred to an image forming support. In the image forming method including a step of fixing by a fixing device, the fixing device includes a heating roller, and a pressure roller that is in contact with the heating roller, the heating roller,
The inner diameter is made of a metal or an alloy selected from aluminum, iron and copper, having an inner diameter of 10 to 50 mm and a thickness of 0.1.
Fluorine resin is coated on the surface of a core metal having a hardness of ~ 2 mm, and a heating member fixed and arranged is included therein. It is coated on the surface of the core metal with thickness,
The pressure roller and the heating roller are 4 to 35k.
gf, wherein the toner comprises a binder resin containing a crystalline substance and an amorphous polymer, and a colorant.
C shows an endothermic peak (P1) in the first heating process of 50
１３０130 ° C., the exothermic peak (P2) in the first cooling process by DSC is 30-110 ° C., and P1 ≧ P2
An image forming method, wherein the toner satisfies the following.