JP2001075312A - Nonmagnetic one-component toner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To ensure a proper quantity of electric charges by rapid build-up of electrostatic charge, to suppress excess toner fogging to a photoreceptor and to prevent the stain of a white ground part of printed matter by incorporating a specified negative charge type electrostatic charge controlling agent and an ethylene-propylene copolymer having a specified melting point as toner components. SOLUTION: The nonmagnetic one-component toner contains at least a polyester resin, a colorant, a metal-containing azo compound as an electrostatic charge controlling agent and an ethylene-propylene copolymer having 125-140 deg.C melting point. The average particle diameter of toner particles is 4-20 μm, preferably 5-12 μm. The molecular weight of the ethylene-propylene copolymer is 2,000-30,000, preferably 5,000-25,000, further preferably 7,000-25,000. A preferred amount of the copolymer is 0.05-10 pts.wt., in particular 0.1-6 pts.wt. based on 100 pts.wt. bonding resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a non-magnetic one-component toner for developing an electrostatic image in electrophotography, electrostatic charge recording, electrostatic printing and the like.

[0002]

2. Description of the Related Art Conventionally, as an electrophotographic method, US Pat.
No. 221776, No. 2297691, No. 2357
As described in the specification such as 809, the photoconductive insulating layer is uniformly charged (charging step), and then the layer is exposed (exposure step) to dissipate the charge in the exposed portion. Thus, an electrostatic latent image is formed, and the electrostatic latent image is visualized by attaching a charged colored fine powder (toner) thereto (development step). After the image is transferred onto the transfer material (transfer step), the image is permanently fixed by heating, pressure or other appropriate means (fixing step). After the transfer of the toner image, the residual toner on the photoconductor is scraped off to clean the photoconductor surface (cleaning step).

Conventionally, a two-component magnetic brush developing method using a two-component developer with a toner and a carrier used to impart a charge to the toner and transport the toner to an electrostatic latent image portion by a magnetic force is used. , Which has been most conveniently used. Further, for example, as proposed in U.S. Pat. Nos. 3,909,258 and 4,121,931, a magnetic substance is included inside the toner without using a carrier, and the toner is electrostatically latent by the magnetic force of the toner. The magnetic one-component developing method of transporting to the image area has been more often used than before.

[0004] More recently, US Patent No. 2,895,847.
And JP-B-3152012, JP-B-41-
Nos. 9475, 45-2877 and 54-3
As described in Japanese Patent No. 624 or the like, a non-magnetic one-component developing method using only a toner containing no magnetic powder is also used. This developing method is advantageous in reducing the size and weight of the recording apparatus in that a magnet is not used for the developing roll. In particular, small-sized personal copying machines, printers, and plain paper fax machines, and full-color copying machines and printers, which have been actively developed in recent years, are increasingly using this developing method.

For example, for a full-color printer using a non-magnetic one-component toner by adopting a reversal developing method, compactness, high speed, low energy fixing, transparency at the time of projecting an overhead projector (hereinafter referred to as OHP), There is a demand for higher image quality. For this reason, as the size of the printer is reduced, the size of the developing device, the photoconductor, and the fixing device tends to be reduced. Therefore, in the developing device, the small-diameter developing roll is rotated at a high speed, so that the charging of the toner is lessened, and the charging startability is deteriorated.
As a result, toner fog on the photoreceptor increases, and white stains on printed matter occur. Also, the lower the toner charge amount, the lower the development amount, the lower the final print density, or the poor charging impairs the uniformity of the toner layer on the developing roll and deteriorates the uniformity of the solid image. Will be. In the fixing section, for example, the toner is heated by an upper heating roll having a heater therein and a lower pressure roll to heat the toner to apply pressure, and the toner is fixed. The contact nip width becomes small, and the heat and pressure are not sufficiently applied to the toner, so that the fixing becomes insufficient. Furthermore, because of insufficient fixing, the smoothness of the toner layer on the OHP sheet is impaired, and the transparency in the OHP sheet is deteriorated.

[0006] Examples of the addition of a wax to improve these properties include, for example, JP-A-49-65231, JP-A-58-16250, JP-A-50-27546, and JP-A-55-153944. Japanese Patent Application Laid-Open Nos. 9-73187 and 9-73187.
Japanese Patent Application Publication No. 0808 and the like propose that carnauba wax is contained in the toner, but it has not been sufficient yet. Examples of using a metal-containing compound as a charge control agent are described in JP-A-9-146295 and JP-A-2-146.
153362, JP-A-7-319241,
It has been proposed in Japanese Patent Application Laid-Open No. 61-155644, but it has not always been sufficient.

[0007]

Accordingly, the first aspect of the present invention is as follows.
The purpose of the development is to provide a developing device equipped with a small developing roll using a non-magnetic one-component system and a charging blade. It is an object of the present invention to provide a non-magnetic one-component toner which can ensure a sufficient amount of toner fogging on the photoreceptor, does not stain white portions of printed matter, and has good uniformity of a solid image. A second object of the present invention is to provide a non-magnetic one-component toner which can be sufficiently fixed without occurrence of offset in a fixing device of a small contact type heat roll.

[0008]

Means for Solving the Problems The present inventors have made intensive studies in view of the above circumstances, and as a result, have found that a specific negatively chargeable charge control agent,
By including an ethylene / propylene copolymer having a specific melting point as a toner component, the problem of the conventional toner was solved, and it was found that the toner exhibited excellent characteristics, and the present invention was completed. That is, the gist of the present invention is to provide at least a polyester resin, a colorant, a charge controlling agent for a metal-containing azo compound, and ethylene / melting point of 125 to 140 ° C.
Non-magnetic one-component toner containing a propylene copolymer.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. The toner particles used in the present invention are a fine powder in which a colorant, a charge controlling agent, an ethylene-propylene copolymer, and other additives are dispersed and contained as necessary in a polyester resin, and the average particle size of the toner particles is 4-20μ
m, preferably 5 to 12 μm. The toner particle size can be measured, for example, with a Coulter counter manufactured by Coulter Inc., a multisizer, or the like.

As the polyester resin used in the present invention, a known polyester resin suitable for a toner can be used. The polyester resin comprises a polyhydric alcohol and a polybasic acid, and if necessary, these polyhydric alcohol and polybasic acid are used. It is preferable that at least one of them is obtained by polymerizing a monomer composition containing a trifunctional or higher polyfunctional component (crosslinking component). In the above, examples of the dihydric alcohol used for the synthesis of the polyester resin include ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, and neopentyl. Glycols, 1,4-butenediol, 1,5-pentanediol, diols such as 1,6-hexanediol, bisphenol A, hydrogenated bisphenol A,
Examples thereof include bisphenol A alkylene oxide adducts such as polyoxyethylenated bisphenol A and polyoxypropylene oxidized bisphenol A, and the like. Among these monomers, it is particularly preferable to use a bisphenol A alkylene oxide adduct as a main component monomer, and particularly preferably an adduct having an average alkylene oxide addition number of 2 to 7 per molecule.

Examples of the trihydric or higher polyhydric alcohol involved in the crosslinking of polyester include sorbitol,
1,2,3,6-hexanetetrol, 1,4-sorbitan, pentaerythritol, dipentaerythritol, tripentaerythritol, sucrose, 1,2,4-butanetriol, 1,2,5-pentanetriol, glycerol , 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, trimethylolpropane, 1,3,5-trihydroxymethylbenzene, and the like.

On the other hand, polybasic acids include, for example, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, phthalic acid, isophthalic acid, terephthalic acid, cyclohexanedicarboxylic acid, succinic acid, adipic acid, sebacic acid, azelaic acid Examples thereof include acids, malonic acids, anhydrides of these acids, lower alkyl esters, alkenylsuccinic acids or alkylsuccinic acids such as n-dodecenylsuccinic acid and n-dodecylsuccinic acid, and other divalent organic acids.

Examples of the tribasic or higher polybasic acid involved in the crosslinking of polyester include 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid,
1,2,4-cyclohexanetricarboxylic acid, 2,5
7-naphthalenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, 1,3-dicarboxyl-2-methyl-2-methylenecarboxypropane, tetra (methylenecarboxyl) methane, Examples thereof include 1,2,7,8-octanetetracarboxylic acid, anhydrides thereof, and others.

These polyester resins can be synthesized by an ordinary method. Specifically, the reaction temperature (1
Conditions such as 70 to 250 ° C.) and reaction pressure (5 mmHg to normal pressure) may be determined according to the reactivity of the monomer, and the reaction may be terminated when predetermined physical properties are obtained. The softening temperature (Sp) of these polyester resins is 80 to
160 ° C is preferable, and among them, those having a temperature of 90 to 150 ° C are more preferable. Also, its glass transition temperature (Tg)
Is preferably 50 to 75 ° C, and among them, 55 to 70 ° C
Are more preferred. If Sp is lower than the above range, an offset phenomenon at the time of fixing tends to occur. On the other hand, if it is higher than the above range, fixing energy increases, and glossiness and transparency of color toner tend to deteriorate, which is not preferable. When the Tg is lower than the above range, the toner tends to aggregate and fix, and when the Tg is higher than the above range, the fixing strength at the time of thermal fixing tends to decrease, which is not preferable. Sp can be controlled mainly by the molecular weight of the resin, and the number average molecular weight is preferably 2,000 to 20,000, more preferably 3,000 to 12,000. Also,
Tg can be adjusted mainly by selecting a monomer component constituting the resin, and specifically, Tg can be increased by using an aromatic polybasic acid as a main component as an acid component. That is, among the above-mentioned polybasic acids, phthalic acid, isophthalic acid, terephthalic acid, 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid and the like, and anhydrides and lower alkyl esters thereof are used. It is desirable to use it as a main component.

The Sp of the polyester resin is JIS K72.
The measurement was performed using a flow tester described in No. 10 and K6719. Specifically, a flow tester (CFT-
500, manufactured by Shimadzu Corporation) using a heating rate of 3 ° C./min. In while heating, applying a load of 30kg / cm ² by a plunger of surface area 1 cm ^2, hole diameter 1
mm, a temperature corresponding to an intermediate point between the temperature at which the plunger starts to descend and the temperature at which the plunger ends is defined as the softening temperature.

Tg is measured by a differential scanning calorimeter (DS).
C) was performed at a heating rate of 10 ° C./min. By the way, when the acid value of the polyester resin is generally too high,
Since it is difficult to obtain a stable high charge amount and the charge stability at high temperature and high humidity tends to deteriorate, the acid value is set to 30 KOHmg / g or less, more preferably 20 KOHmg / g in the present invention. g or less. As a method for adjusting the acid value within the above range, other than a method of controlling the addition ratio of the alcohol-based and acid-based monomers used in the resin synthesis, for example, the acid monomer component is previously converted to a lower alkyl ester by a transesterification method. And a method of neutralizing residual acid groups by adding a basic component such as an amino group-containing glycol into the composition, but not limited thereto. It goes without saying that the method can be adopted. The acid value of the polyester resin is measured according to JIS K0070. However, when the resin is difficult to dissolve in the solvent, a good solvent such as dioxane may be used. These binder resins may be used alone or in combination of two or more different resins from among known resins, or may be used alone or in combination of two or more resins having different viscoelastic properties, thermal properties such as different molecular weight distributions even in the same type of resin. You may use together.

The colorant used in the present invention includes carbon black; I. Pigment Yellow 1, 3, 74, 97, 98, etc .; acetoacetic arylamide monoazo yellow pigments; C.I. I. Pigment Yellow 12, 13, 14, and 17 acetoacetic acid arylamide-based disazo yellow pigments; C.I. I. Condensed monoazo yellow pigments such as CI Pigment Yellow 93 and 155;
C. I. Pigment Yellow 180, 150, 1
Other yellow pigments such as 85; I. Solvent Yellow 19, 77, 79, C.I. I. Yellow dyes such as Disperse Yellow 164;

C. I. Pigment Red 48, 4
9: 1, 53: 1, 57, 57: 1, 81, 122, 5, 146, 184, 238;
I. Red or red pigments such as CI Pigment Violet 19; I. Red dyes such as Solvent Red 49, 52, 58 and 8; C.I. I. Pigment Blue 15: 3, 15: 4, etc., blue colourants of copper phthalocyanine and derivatives thereof; I. Green pigments such as CI Pigment Green 7 and 36 (phthalocyanine green) can be used, and they may be used alone or in combination of two or more. The amount of the coloring agent used is 100
The amount is preferably about 1 to 15 parts by weight, more preferably 2 to 10 parts by weight based on parts by weight.

As a full-color toner, there are usually cyan,
In addition to three color toners of magenta and yellow, four color toners of black toner are used. As the colorant for the cyan toner when used in a full-color toner, C.I.
I. Pigment Blue 15: 3 blue pigments are preferred. Examples of the colorant for magenta toner include C.I. I.
Pigment Red 57: 1, 122, 146, 184, 238, and C.I. I. Pigment Violet 19 red or red pigments are preferred.

As the colorant for the yellow toner, C.I.
I. Pigment Yellow 13, 17, 17, and 9
3, 150, 155, 180, and 185 are preferred. Carbon black is used as the colorant of the black toner, and carbon black having an ultraviolet absorbance of 0.05 or less described in JP-A-6-175403 or the like is preferable because uniform and good chargeability can be obtained. Further, it is preferable that the PH of the carbon black is 7 or less, because the negatively charged amount becomes better.

The charge control agent used in the present invention is a metal-containing azo compound. As the metal component of the metal-containing azo compound, chromium or iron is preferable. Examples of the chromium-azo compound include Bontron S manufactured by Orient Chemical Industry Co., Ltd.
-34, S-54 and T-95 manufactured by Hodogaya Chemical Industry Co., Ltd. The ratio of the major axis to the minor axis of the chromium-azo compound used in the present invention is preferably 3 or less, more preferably 2 or less. When the ratio of the major axis / minor axis is significantly larger than the above range, the offset occurrence temperature of the toner tends to decrease. The shape of the charge controlling agent is measured by taking a photograph with a scanning electron microscope at a high magnification, measuring the length direction of the 100 or more particles as the long diameter, and measuring the short direction as the short diameter, and calculating the long diameter / short diameter of each particle. What is necessary is just to calculate those average values. The chromium / azo compound used in the present invention is preferably a compound represented by the following general formula (1).

[0022]

Embedded image (In the formula, A to D may be the same or different and each represents a benzene ring which may be substituted. X ⁺ represents a cation.) In the formula (1), substitution of the benzene ring of A to D Examples of the group include an alkyl group, a halogen atom, a cyano group, a nitro group,
A hydroxyl group and an alkoxy group are preferred, and a chlorine atom is more preferred. X ⁺ represents a cation, and is preferably a hydrogen ion, an alkali metal ion, or an ammonium ion.

The iron / azo compound used in the present invention is preferably a compound represented by the following general formula (2).

[0024]

Embedded image

(Wherein, E to J may be the same or different and each represents an optionally substituted benzene ring.
X ⁺ represents a cation. )

In the general formula (2), when the benzene ring of E to J has a substituent, the substituent may be a halogen atom, a sulfonamide group, a mesyl group, a sulfonic acid group, a hydroxyl group, an amino group. Represents an alkoxycarbonyl group, an acetylamino group, a benzoylamino group, an optionally substituted hydrocarbon group, or an optionally substituted alkoxy group, wherein the substituent is an alkyl group, an alkenyl group, a halogen atom, a cyano group. , A hydroxyl group, an amino group and a nitro group are preferred, a halogen atom and an alkoxy group are more preferred, and a chlorine atom and a methoxy group are particularly preferred. X ⁺ represents a cation, preferably a hydrogen ion, an alkali metal ion, or an ammonium ion, and more preferably a sodium ion or a potassium ion.

The iron-containing compound represented by the general formula (2) is
Japanese Patent Application Laid-Open No. Sho 61-155644 discloses a method for producing the compound, which can be easily synthesized according to this method. However, commercially available products such as T-7 manufactured by Hodogaya Chemical Industry Co., Ltd.
7 or the like can also be used.

The charge controlling agent used in the present invention includes:
In addition to the charge control agent, as to impart a negative charge,
Surfactants such as naphtholic acid or its derivatives, chromium / zinc / aluminum / boron complexes or salt compounds, long-chain alkyl carboxylate, long-chain alkyl sulfonate, etc., and also impart positive chargeability For example, a small amount of a derivative such as a nigrosine dye or a derivative thereof, a triphenylmethane derivative, a quaternary ammonium salt, a quaternary phosphonium salt, a quaternary pyridinium salt, a guanidine salt, or an amidine salt may be used.

In order to improve the dispersibility and compatibility of the colorant and the charge controlling agent in the toner, a preliminary dispersion treatment, that is, a so-called master batch treatment, may be performed in advance by kneading with a resin or the like.

The ethylene / propylene copolymer used in the present invention has a melting point of 125 to 140 ° C, more preferably 125 to 135 ° C. The molecular weight is usually in the range of 2,000 to 30,000, preferably in the range of 5,000 to 25,000, more preferably in the range of 7000 to 25,000. Ethylene / propylene copolymers having a melting point of less than 125 ° C. are not preferred because they cause problems in stable production, and if the melting point exceeds 140 ° C., the low-temperature fixability of the toner is impaired. On the other hand, if the molecular weight is significantly smaller than the above range, there is a problem in the stable production of the ethylene / propylene copolymer, and the filming phenomenon on the photoreceptor and the developing member tends to occur.
On the other hand, when the molecular weight is significantly larger than the above range, the hot offset property tends to deteriorate.

The amount of the ethylene / propylene copolymer to be added is preferably 0.05 to 10 parts by weight, more preferably 0.1 to 6 parts by weight, based on 100 parts by weight of the binder resin. preferable. If the addition amount is significantly lower than the above range, the effect of improving the hot offset property tends to be low, and the fog on the photoreceptor and the white background stain on plain paper tend to be poor. If the addition amount is significantly higher than the above range, the filming phenomenon on the photosensitive member and the developing member tends to occur, and the poor transportability due to the deterioration of the toner fluidity tends to occur.

The production of the ethylene / propylene copolymer is as follows:
A known method is used and is not particularly limited. Examples of the method include a high-pressure radical polymerization method, a medium- and low-pressure polymerization method performed in the presence of various transition metal compound catalysts such as a Ziegler catalyst, and a method of heating and degrading a high-molecular-weight ethylene-propylene copolymer. For toner applications, a heat degradation method is preferred, in which a high molecular weight ethylene / propylene copolymer is thermally decomposed in a reactor at a heating temperature of 300 to 400 ° C,
It is preferable to obtain an ethylene / propylene copolymer having a desired melting point and molecular weight. The melting point can be adjusted by adjusting the molar ratio of ethylene and propylene, and the molecular weight can be adjusted by adjusting the degree of thermal decomposition based on the thermal decomposition temperature, time, and the like.

The melting point of the ethylene / propylene copolymer is as follows:
Using a differential scanning calorimeter (DSC), the temperature was raised at a rate of 10 ° C./m.
The temperature corresponds to the endothermic peak point at "in". The molecular weight is a value converted into a molecular weight by a solution viscosity method based on ASTM D445.

In the present invention, various kinds of known organic or inorganic fine powders may be used as other additives for the purpose of improving the adhesiveness, cohesiveness, fluidity, chargeability and the like of the toner particles. The fine particle powder to be added to the toner surface, so-called external additive, preferably has a primary particle diameter of 0.001 to 5 μm, particularly preferably 0.002 to 3 μm, and the surface thereof may be subjected to a treatment such as hydrophobization. . Examples of the fine particle powder include organic and inorganic fine particles, for example, polyvinylidene fluoride, a fluororesin powder such as polytetrafluoroethylene, a fatty acid metal salt such as zinc stearate and calcium stearate, a polymethyl methacrylate or a silicone resin as a main component. And inorganic fine powders such as silicon oxide, aluminum oxide, titanium oxide, zinc oxide, tin oxide, cerium oxide, strontium titanate, and conductive titania. .

Among these, silicon oxide, aluminum oxide, and titanium oxide fine particles are more preferable, and those whose surfaces are subjected to a hydrophobic treatment are particularly preferable. As a method of hydrophobization, for example, there is a method of reacting or physically adsorbing fine particles with an organic silicon compound such as hexamethyldisilazane, trimethylsilane, dimethyldichlorosilane, or silicon oil, and chemically treating them. The addition ratio of these fine particle additives to the toner is 10% by weight.
0: 0.01 to 10 is preferable, and 100: 0.05 is particularly preferable.
To 8 are more preferable. In a non-magnetic one-component toner, two types of relatively large particles (less than 90 m ² / g in BET specific surface area) and small particles (90 m ² / g or more in BET specific surface area) of these fine particle additives are used. It is preferable to use them in combination.

In the toner according to the present invention, any known substance such as a releasing agent such as low molecular weight polyethylene, paraffin wax, montan wax and carnauba wax can be contained as other components. . The non-magnetic toner according to the present invention can be manufactured by various manufacturing methods including a conventionally known method, and a general manufacturing method includes the following process examples (1) to (6).

(1) The resin, the charge control substance, the colorant and the additives to be added as required are uniformly dispersed by a mixing device having a rotating portion such as a blade or a screw. As the mixing device, a Henschel mixer manufactured by Mitsui Mining Co., Ltd., a Ladige mixer manufactured by Masbo, a Nauta mixer manufactured by Hosokawa Micron, a super mixer manufactured by Kawata, or a general V-type mixer in which the container itself rotates can be used. .

(2) The dispersion is melt-kneaded with a kneader, extruder, roll mill or the like. Examples of the kneading apparatus include continuous extruders such as a ZSP extruder manufactured by W & P, a co-kneader manufactured by BUSS, a TEM extruder manufactured by Toshiba Machine Co., a PCM extruder manufactured by Ikegai, and a Nidex manufactured by Mitsui Mining Co., Ltd. A general batch-type kneader can also be used. As a cooling device after the kneading, a drum cooler manufactured by Mitsui Mining Co./Mitsubishi Chemical Engineering Co., Ltd., a belt cooler manufactured by NBC Co., etc. can be used.

(3) After coarsely pulverizing the kneaded material with a coarse pulverizer,
Pulverize with a pulverizer. As a crusher, NPK I
Type / IDS type jet mill, Hosokawa Micron AF
G / TJM and other jet mills; Hosokawa Micron's Hammer Mill, Fats Mill, Feather Mill, Inomaizer, ACM Pulperizer, Turbo Mill's Turbo Mill, Kawasaki Heavy Industries' KTM, Nisshin Engineering's Super Rotor, NPK's Fine Mill The toner is crushed stepwise to a predetermined toner particle size using an impact crusher or the like.

(4) The finely pulverized material is classified by a classifier. Alpine / Hosokawa Micron TSP,
An airflow classifier with a rotating rotor inside the machine, such as a turbo qualifier manufactured by Nisshin Engineering Co., Ltd., CFS-HD manufactured by Condax / Mitsui Mining Co., Ltd., Donasex manufactured by Donaldson Co., Ltd., a DS / DSX type classifier manufactured by NPK, Using an elbow jet classifier manufactured by Iron Mining Co., Ltd., and a micron separator manufactured by Hosokawa Micron Co., Ltd., the toner is classified stepwise to a predetermined toner particle size. The coarse powder generated in the classification process is
Alternatively, it may be returned to the first-stage classification step and reused. Further, the toner fine powder may be reused by returning to the raw material mixing step and the kneading step.

(5) In the case of further external addition treatment, a predetermined amount of the classified product and various known external additives are blended, and the mixture is stirred by a high-speed stirrer such as a Henschel mixer or a super mixer which applies a shearing force to the powder.・ Mix. (6) In order to remove foreign matter and coarse particles, the final toner is obtained after sieving using a vibrating sieve such as a gyro shifter, a Sato type vibrating sieve, an ultrasonic sieve or a rotary sieve such as a turbo screener. be able to.

Further, as a method completely different from the above-mentioned production method, for example, toner particles may be formed by a production method using a suspension polymerization method or an emulsion polymerization method, that is, a so-called polymerization toner method. The obtained toner preferably has a softening temperature of 90 to 140 ° C and a glass transition temperature of 50 to 70 ° C. If the softening temperature is lower than 90 ° C., the hot offset property deteriorates, and the mechanical strength decreases, which is not preferable. On the other hand, if it exceeds 140 ° C., the fixing property deteriorates, which is not preferable. Glass transition temperature is 50
When the temperature is lower than 70 ° C., toner aggregation and fixation are liable to occur.

The softening temperature of the toner was measured using a flow tester (C
FT-500, manufactured by Shimadzu Corporation), and about 1 g of a sample was heated at a rate of 6 ° C./min. 1cm ² while heating with
A load of 20 kg / cm ² by the plunger of
It is extruded from a die having a hole diameter of 1 mm and a height of 1 mm, and a temperature corresponding to an intermediate point between the temperature at which the plunger starts to descend and the temperature at which it descends is defined as the softening temperature. Further, the glass transition temperature of the toner was once raised to 100 ° C. or more at a rate of 10 ° C./min using a differential scanning calorimeter (DSC).
The temperature was measured after cooling to room temperature by air cooling with a fan and raising the temperature again.

The toner of the present invention is developed by a non-magnetic one-component developing system in electrophotography, and then an image is formed by a heat fixing system in which the toner is fixed by bringing the toner into contact with a fixing roll having a built-in heat heater. It is useful when used for

An example of an electrophotographic recording apparatus using the toner of the present invention will be described below, but the present invention is not limited to this example. FIG. 1 is a schematic view of a main part configuration of an electrophotographic recording apparatus, in which a photosensitive member 1, a charging device 2, an exposure device 3,
The image forming apparatus includes a developing device 4, a transfer device 5, a cleaning device 6, and a fixing device 7. The photoreceptor 1 is formed of a conductor such as aluminum, for example, and has a photosensitive layer formed by applying a photosensitive conductive material on the outer peripheral surface. A charging device 2, an exposure device 3, a developing device 4, a transfer device 5, and a cleaning device 6 are arranged along the outer peripheral surface of the photoreceptor 1, respectively.

The charging device 2 is composed of, for example, a well-known scorotron charger, roller charger, etc., and uniformly charges the surface of the photoconductor 1 to a predetermined potential. The exposure device 3 includes the photoconductor 1
The photosensitive surface of the photosensitive member 1 is exposed by an LED, a laser beam, or the like to form an electrostatic latent image on the photosensitive surface. The developing device 4 includes an agitator 42, a supply roller 43, a developing roller 44, and a developing blade 45, and stores the toner T therein. If necessary, the developing device may be provided with a replenishing device (not shown) for replenishing toner.
The replenishing device can replenish toner from a container such as a bottle or a cartridge.

The supply roller 43 is made of a conductive sponge or the like, and rotatably contacts the developing roller 44. The developing roller 44 includes the photosensitive member 1 and the supply roller 43.
And is located between. The developing roller 44 is rotatably in contact with each of the photoconductor 1 and the supply roller 43. The supply roller 43 and the developing roller 44 are rotated by a rotation drive mechanism. The supply roller 43 carries the stored toner and supplies it to the developing roller 44. The developing roller 44 carries the toner supplied by the supply roller 43 and contacts the surface of the photoconductor 1.

The developing roller 44 is made of a metal roll such as SUS or aluminum, or a metal roll made of a silicone resin,
It is made of a resin roll coated with urethane resin, fluororesin or the like. The surface of the developing roller 44 may be smoothed or roughened as necessary. The developing blade 45 is made of resin such as silicon resin or urethane resin, S
It is formed of a metal such as US, aluminum, copper, brass, phosphor bronze and the like. The developing blade 45 is in contact with the developing roller 44 by being urged against the developing roller 44 by a predetermined force by a spring or the like.

The agitator 42 is rotated by a rotation drive mechanism, and agitates the toner and conveys the toner to the supply roller 43 side.
A plurality of agitators 42 may be provided with different blade shapes, sizes, and the like. The transfer device 5 applies a predetermined voltage value (transfer voltage) having a polarity opposite to the charged potential of the toner, and transfers the toner image formed on the photoconductor 1 to the paper P.

The cleaning device 6 comprises a cleaning member such as a urethane blade or a fur brush.
This is to scrape off the residual toner attached to the photoconductor 1 and collect the residual toner. The fixing device 7 includes an upper fixing member 71 and a lower fixing member 72, and has a heating device 73 inside the upper or lower fixing member. As the fixing member, a known heat fixing member such as a fixing roll in which a metal tube made of SUS or aluminum is coated with silicon rubber, a fixing roll in which Teflon resin is coated, and a fixing sheet can be used. Further, a releasing agent such as silicone oil may be supplied to the fixing member to improve the releasing property.
Further, a mechanism for forcibly applying pressure to the upper fixing member and the lower fixing member by a spring or the like may be employed. When the toner transferred onto the paper P passes between the upper fixing member 71 and the lower fixing member 72 heated to a predetermined temperature, the toner is heated to a molten state, cooled after passing through, and cooled on the paper P. The toner is fixed.

In the electrophotographic developing apparatus configured as described above, an image is recorded as follows. That is, first, the surface (photosensitive surface) of the photoconductor 1 is charged to a predetermined potential (for example, −600 V) by the charging device 2. continue,
The charged photosensitive surface of the photoreceptor 1 is exposed by the exposure device 3 in accordance with an image to be recorded, and an electrostatic latent image is formed on the photosensitive surface. Then, the developing device 4 develops the electrostatic latent image formed on the photosensitive surface of the photosensitive member 1.

The developing device 4 thins the toner supplied by the supply roller 43 by the developing blade 45.
The toner is frictionally charged to a predetermined polarity (here, the same polarity as the charged potential of the photoconductor 1 and has a negative polarity), and is carried by the developing roller 44, transported, and brought into contact with the surface of the photoconductor 1. The toner is reversed from the developing roller 44 to the surface of the photoconductor 1 by a so-called reversal developing method, and a toner image corresponding to the electrostatic latent image is formed. Then, the toner image is transferred to the sheet P by the transfer device 5. Thereafter, the photosensitive member 1
The remaining toner without being transferred to the photosensitive surface is removed by the cleaning device 6. The final image is obtained by passing the toner on the sheet P through the fixing device 7 and thermally fixing the toner.

[0053]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, which should not be construed as limiting the scope of the invention. In addition, in each of Examples and Comparative Examples, “parts” simply means “parts by weight”. [Example 1]

[0054]

100 parts of nonlinear polyester resin A Softening temperature: 150 ° C. Glass transition temperature: 65 ° C. Acid value: 8 KOH mg / g Hydroxyl value: 30 KOH mg / g Mn: 2400, Mw: 87000 ・ Ethylene / propylene copolymer p 0 0.5 part Melting point: 132 ° C Molecular weight: 7100 Density: 0.90 kg / m ³ ・ Charge control agent 1 part of Bontron S-54 manufactured by Orient Chemical Industry Co., Ltd. [irregular shape, major axis / minor axis ratio is 1.5] ・ Carbon black 5 parts MA-100S manufactured by Mitsubishi Chemical Corporation [pH: 3.0, UV absorbance] : 0.03]

The above composition is premixed with a high-speed stirrer, kneaded with a twin-screw continuous extruder, and then rapidly cooled while rolling with two rolls. The cooled product was coarsely pulverized by a feather mill until it passed the 2 mm line, and then adjusted to a volume average particle diameter of about 8.7 μm with a jet pulverizer / airflow classifier to obtain a classified toner. The particle size was measured with a Coulter Multisizer. The softening temperature of the toner is 140
° C and the glass transition temperature was 65 ° C. Then, 100 parts of the classified toner and RY50 silica manufactured by Nippon Aerosil Co., Ltd.
Five parts were mixed with a Henschel mixer, and 0.5 part of R812 silica manufactured by Nippon Aerosil Co., Ltd. was further added and mixed to prepare Black Toner a. As a result of evaluating the fixing characteristics,
High-temperature offset generation temperature 220 ° C or higher, fixing temperature 12
The temperature range was 0 ° C. and the temperature range was good. The image characteristics were evaluated using a commercially available tandem mechanism color printer B (plain paper passing speed 60 mm / sec, A4 plain paper color printing speed 8 sheets / min, non-magnetic one-component contact developing system). The image characteristics were good, with no white background staining and no fogging of the toner on the organic photoreceptor when printing on a white background. [Example 2]

[0056]

[Table 2]-Charge control agent 1 part of Bontron S-34 manufactured by Orient Chemical Industries Co., Ltd. [needle-shaped, ratio of major axis / minor axis of 5.4]

Black toner b was prepared in the same manner as in Example 1 except that S-34 was used as one part instead of S-54 as the charge control agent in Example 1. The softening temperature of the toner was 140 ° C., and the glass transition temperature was 65 ° C. As a result of evaluating the fixing characteristics, it was found that the high-temperature side offset occurrence temperature was 2
There was a tendency that the temperature was as low as 10 ° C., the fixing temperature was 130 ° C., and the working temperature range was somewhat narrow. Further, as a result of evaluating the image characteristics with the color printer B, there was almost no fog on the organic photoreceptor when printing on a white background, the image density of plain paper was good, and there was almost no fog on the white background. [Example 3]

[0058]

[Table 3] ・ Carbon black # 44, 5 parts, manufactured by Mitsubishi Chemical Corporation [pH: 8.0, UV absorbance: 0.03]

The carbon black of Example 1 was replaced with MA-10
Example 1 except that the above # 44 was replaced with 5 parts instead of 0S
The black toner c was adjusted in the same manner as described above. The softening temperature of the toner was 140 ° C., and the glass transition temperature was 65 ° C.
Met. The fixing characteristics of this toner were the same as those of the toner a. Further, as a result of evaluating the image characteristics with the color printer B, there was almost no fog on the organic photoreceptor when printing on a white background, the image density of plain paper was good, and there was almost no fog on the white background. [Comparative Example 1]

[0060]

[Table 4] ・ Charge control agent 1 part of Copy Charge NCA LP2243 (cyclic oligosaccharide) manufactured by Clariant

A black toner d was prepared in the same manner as in Example 1 except that the charge control agent of Example 1 was changed to LP-2243 in place of S-54. The toner softening temperature was 140 ° C. and the glass transition temperature was 64 ° C.

The fixing characteristics of this toner were almost good in the operating temperature range, with a high temperature side offset occurrence temperature of 220 ° C. and a fixing temperature of 120 ° C. In addition, the evaluation results of the color printer B showed that the fogging on the organic photoreceptor at the time of printing on a white background was considerably large and the fogging of plain paper on a white background was poor. [Example 4]

[0063]

[Table 5] 100 parts of linear polyester resin A Softening temperature: 106 ° C., Glass transition temperature: 62 ° C. Acid value: 10 KOH mg / g, Hydroxyl value: 37 KOH mg / g Mn: 3100, Mw: 7,700 1 part of T-77 manufactured by Tsuchiya Chemical Co., Ltd. 0.5 part of ethylene-propylene copolymer p Melting point: 132 ° C. Number average molecular weight: 7100 Density: 0.90 kg / m ³ Carbon black MA-100S 5 manufactured by Mitsubishi Chemical Corporation Part [pH: 3.0, UV absorbance: 0.03]

The above composition is premixed with a high-speed stirrer, kneaded with a twin-screw continuous extruder, and then cooled rapidly while rolling with two rolls. The cooled product was coarsely pulverized by a feather mill until it passed the 2 mm line, and then adjusted to a volume average particle diameter of about 8.2 μm by a jet pulverizer / airflow classifier to obtain a classified toner. The particle size was measured with a Coulter Multisizer. Next, 100 parts of the classified toner and 1.5 parts of RY50 silica manufactured by Nippon Aerosil Co., Ltd. were mixed with a Henschel mixer, and 0.5 part of R812 silica manufactured by Nippon Aerosil Co., Ltd. was further added and mixed.
Was adjusted. Table 1 shows the fixing characteristics of the toner. As a result, the fixing characteristics were good. Next, the actual printing test of the toner was performed using a color printer A of a commercially available intermediate transfer mechanism (plain paper passing speed of 96 mm / sec, A4 plain paper color printing speed of 4 sheets / min, non-magnetic one-component contact developing system). As a result, the image characteristics were good, such as good image density and no white background stain. [Comparative Example 2]

[0065]

* Ethylene / propylene copolymer q 0.5 part Melting point: 144 ° C. Number average molecular weight: 7000 Density: 0.90 kg / m ³

In place of the ethylene / propylene copolymer p in Example 4, 0.5 was added to the ethylene / propylene copolymer q.
The black toner K2 was adjusted in the same manner as in Example 4 except that the number of copies was set as a unit. The fixing characteristics of this toner are shown in Table 1. As a result, the minimum fixing temperature of plain paper was
The cold offset non-generation temperature of the P sheet was high, which was not preferable. Further, the result of actual photographing with the color printer A was almost good in both image density and white background fog.
[Comparative Example 3]

[0067]

[Table 7] ・ Charge control agent 1 part of Copy Charge NCA LP2243 manufactured by Clariant

A black toner K3 was prepared in the same manner as in Example 4 except that the charge control agent of Example 4 was changed to LP-1243 instead of T-77. As a result of performing the actual printing test of the toner with the color printer A, the image density was too high and the image characteristics were unfavorable, such as poor white paper fog on plain paper.

Example 5 100 parts of non-linear polyester resin A Charge control agent 1 part of T-77 manufactured by Hodogaya Chemical Industry Co., Ltd. 2 parts of ethylene-propylene copolymer p Carbon black MA-100S manufactured by Mitsubishi Chemical Corporation 4 parts A classified toner was obtained in the same manner as in Example 1 except that the composition of Example 1 was changed to the above composition. Next, 100 parts of the classified toner and 1.8 parts of RY50 silica manufactured by Nippon Aerosil Co., Ltd. were mixed with a Henschel mixer, and R8 manufactured by Nippon Aerosil Co., Ltd. was further mixed.
Black silica e was prepared by adding 0.2 part of 12 silica and additionally mixing. The softening temperature of the toner was 140 ° C.
Glass transition temperature was 65. As a result of performing a real image test of the toner using the color printer B, image characteristics such as high image density and no white background stain were excellent.

Example 6 Carbon Black # 44, 4 parts, manufactured by Mitsubishi Chemical Corporation The same operation as in Example 5, except that the carbon black of Example 5 was replaced with 4 parts of # 44 above instead of MA-100S, The black toner f was adjusted. The softening temperature of the toner was 140 ° C., and the glass transition temperature was 65 ° C. As a result of carrying out the actual printing test of this toner with the color printer B, the toner stain on the organic photoreceptor when printing on a white background was slightly large, and the white background fog on plain paper was also slightly bad. Poor fog on the photoreceptor may cause color mixing of black toner in the color image area when cyan, magenta, and yellow color toners and black toner are used at the same time, or worsen toner consumption when printing continuously. Is not preferred.

Comparative Example 4 Charge Control Agent Copy Charge NCA LP2243 (Cyclic Oligosaccharide) manufactured by Clariant Co. 1 part The charge control agent of Example 5 was replaced with the above LP2 instead of T-77.
Black toner g was adjusted in the same manner as in Example 5, except that 243 was used as one copy. As a result of carrying out the actual printing test of the toner with a color printer B, the image characteristics were unfavorable, for example, the amount of toner smear on the organic photoreceptor when printing on a white background was considerably large, and the fog on plain paper was poor. The softening temperature of the toner was 140 ° C., and the glass transition temperature was 64 ° C.
Met.

[Evaluation Method] The test method for each evaluation item was as follows. 1. Offset temperature / Minimum fixing temperature A state in which a square black solid image has not been
(Referred to as an unfixed image). Next, the surface temperature of the upper fixing roller is measured by a radiation thermometer using an external fixing machine composed of an upper fixing roller 30φ (containing a temperature-controllable heater inside) and a lower fixing roller 30φ each covered with silicon rubber. The temperature is changed at 5 ° C. while measuring with. At this time, silicon oil is supplied to the upper fixing roller of the external fixing machine so as to be applied, and the nip width of the upper and lower fixing rollers is 4 mm. The passing speed when using plain paper is 100 mm / sec.
The passage speed when the sheet was used was 50 mm / sec.

At each temperature, an unfixed image was passed to obtain a fixed image, and temperatures at which no cold offset and hot offset did not occur from the state of occurrence of an offset were defined as a cold offset non-occurrence temperature and a hot offset non-occurrence temperature, respectively. Further, a square black solid portion of the image fixed at each temperature was rubbed with a finger, and the lowest fixing temperature at which the toner did not fall on the image was defined as the lowest fixing temperature.

[0074]

[Table 8]

[0075]

According to the present invention, the minimum fixing temperature is low and the non-offset temperature region (usable temperature region) is wide by using a non-magnetic one-component toner for developing an electrostatic image in an electrophotographic recording apparatus or the like. This is an excellent effect that the fixing characteristics such as the above are good and good image characteristics can be obtained.

[Brief description of the drawings]

FIG. 1 is a schematic view of a main configuration of an electrophotographic recording apparatus using a toner of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 photoconductor 2 charging device 3 exposure device 4 developing device 5 transfer device 6 cleaning device 7 fixing device 42 agitator 43 supply roller 44 developing roller 45 regulating member 71 upper fixing member 72 lower fixing member 73 heating device T toner P paper

Continued on the front page (72) Inventor Teruki Senoguchi 1 Fukudacho, Joetsu City, Niigata Prefecture Inside the Naoetsu Works, Mitsubishi Chemical Corporation (72) Inventor Takeshi Owada 1 Fukudacho, Joetsu City, Niigata Prefecture Naoetsu Business, Mitsubishi Chemical Corporation In-house (72) Inventor Masakazu Sugihara 1 Fukudacho, Joetsu-shi, Niigata F-term (reference) 2H005 AA01 AA06 AA21 CA08 CA13 CA22 CB18 DA02 EA03 EA06 EA07 EA10 FA07 FB02

Claims (12)

[Claims] (1) at least a polyester resin, a colorant,
A charge controlling agent of a metal-containing azo compound and a melting point of 125 to 1
A non-magnetic one-component toner containing an ethylene / propylene copolymer at 40 ° C. 2. The non-magnetic one-component toner according to claim 1, wherein the metal component of the charge control agent is chromium. 3. The non-magnetic one-component toner according to claim 2, wherein the ratio of the major axis to the minor axis of the charge control agent is 3 or less. 4. The non-magnetic one-component toner according to claim 2, wherein the charge control agent is a compound represented by the following general formula (1). Embedded image (In the formula, A to D may be the same or different, and represent a benzene ring which may be substituted. X ⁺ represents a cation.) 5. The non-magnetic one-component toner according to claim 1, wherein the metal component of the charge control agent is iron. 6. The non-magnetic one-component toner according to claim 5, wherein the charge control agent is a compound represented by the following general formula (2). Embedded image (In the formula, EJ may be the same or different, and represents a benzene ring which may be substituted. X ⁺ represents a cation.) 7. The ethylene / propylene copolymer having a melting point of 125 to 135 ° C.
7. The non-magnetic one-component toner according to any one of items 1 to 6. 8. An ethylene / propylene copolymer having a molecular weight of 2,000 to 30,000, and an addition amount of the ethylene / propylene copolymer of 0.05 to 10 parts by weight based on 100 parts by weight of the polyester resin, 8. The non-magnetic one-component toner according to claim 1, wherein the amount of the charge control agent is 0.05 to 6 parts by weight. 9. The non-magnetic one-component toner according to claim 8, wherein the molecular weight of the ethylene / propylene copolymer is 5,000 to 25,000. 10. The polyester resin having a softening temperature of 8
The non-magnetic one-component toner according to any one of claims 1 to 9, wherein the toner has a glass transition temperature of 0 to 160 ° C, a glass transition temperature of 50 to 75 ° C, and an acid value of 30 KOHmg / g or less. 11. The non-magnetic one-component toner according to claim 1, which is used for a fixing method by heating contact. 12. The non-magnetic one-component toner according to claim 1, wherein the colorant is an acidic carbon black having an ultraviolet absorbance of 0.05 or less.