JP2005091696A - Electrostatic latent image developing toner, toner cartridge, process cartridge, image forming method, and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrostatic latent image developing toner which has excellent fixation properties and hot offset resistance and yields a high-grade image free of fogging. <P>SOLUTION: A binder resin for the electrostatic latent image developing toner is a polycondensated polyester resin formed in the presence of a catalyst containing titanium of at least one kind selected from a group consisting of titanium halide, titanium diketone enolate, titanium carboxylate, titanyl carboxylate, and a titanyl carboxylate salt and contains a high softening point polyester having a softening point of 125 to 150°C and a low softening point polyester of a softening point of 85 to 105°C, wherein a difference of the softening points of the high softening point polyester and that of the low softening point polyester is 20 to 60°C. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a toner for developing an electrostatic latent image used for image formation by an electrostatic copying process such as a copying machine, a facsimile machine, and a printer. Also, the present invention relates to a toner cartridge, a process cartridge, an image forming method, and an image forming method. The present invention relates to an image forming apparatus.

Conventionally, as electrophotography, various methods are described in Patent Document 1, Patent Document 2, and the like. Generally, a photoconductive substance is used and an electric latent image is formed on a photoreceptor by various means. Then, the latent image is developed with toner, and the toner powder image is transferred to paper or the like, if necessary, and then fixed by heating, pressing, or solvent vapor to obtain a copy image.
Methods for developing electrical latent images can be broadly divided into liquid development methods that use a developer in which various pigments and dyes are finely dispersed in an insulating organic liquid, cascade methods, magnetic brush methods, powder cloud methods, etc. Thus, there is a dry development method using a toner in which a colorant such as carbon black is dispersed in a natural or synthetic resin, and there are a one-component development method and a two-component development method using a carrier.

Also, methods for heat-fixing toner images on transfer paper can be broadly classified into contact fixing methods and non-contact fixing methods. The former includes heating roller fixing, belt fixing, the latter includes flash fixing, and oven (atmosphere) fixing. . The heating roller fixing method is a very heat efficient fixing method because the toner image and the heating roller are in direct contact with each other, and the apparatus can be miniaturized, so that it is widely used.
However, due to energy saving in recent years, the heat energy that can be used at the time of fixing has become very small. For this reason, the toner used in such a fixing device is required to be further fixed at a low temperature.

As a technique for solving this problem, several proposals have conventionally been made.
For example, Patent Document 3 discloses a toner for roll fixing in which core particles made of a polyester resin and a wax having a polar group are coated with a resin, and the melt viscosity of the polyester resin and the wax is defined.
Patent Document 4, Patent Document 5, and Patent Document 6 are composed of a specific polyester resin and a release agent, and the melt viscosity at 80 to 120 ° C. of the polyester resin, the slope of the graph of the melt viscosity and the specific release agent. A film fixing toner having a prescribed melt viscosity is disclosed.
Patent Document 7 includes a specific polyester resin and a release agent, and a film fixing that defines the melt viscosity of the polyester resin at 80 to 120 ° C., the gradient of the melt viscosity and temperature, and the melt viscosity of the specific release agent. A capsule toner is disclosed.

Patent Document 8 contains a specific polyester resin, an organometallic compound, and a release agent. The melt viscosity of the polyester resin at 120 to 150 ° C., the gradient of the melt viscosity and the temperature, and the melt viscosity of the specific release agent. A film fixing toner that defines the above is disclosed.
Patent Document 9 discloses a toner composed of a styrene-acrylic resin that defines a relational expression between melt viscosity and temperature measured at 110 to 130 ° C.
Patent Document 10 discloses a toner containing a specific charge control agent and defining an average viscosity gradient.
Patent Document 11 discloses a novel polyester resin in which a polycondensation catalyst of a polyol component and a polycarboxylic acid component is a titanate ester of a diol.
Patent Document 12 discloses a toner containing a polyester resin having a high softening point and a low softening point.

When the polyester resin is used as a toner as in the above prior art, the toner can be fixed even at a low temperature of the hot mouth roller (low temperature fixability), and the toner does not fuse to the heat roll even at a high heat roller temperature. (Hot offset resistance) can be easily achieved, and it is known to be particularly excellent in low-temperature fixability.
However, energy saving is further advanced, and it is difficult to obtain sufficient fixing ability with the conventional technology, and the improvement of filming resistance is insufficient. Improvement in performance is desired.

US Pat. No. 2,297,691 Japanese Patent Publication No.43-24748 Japanese Patent No. 2743476 Japanese Patent Laid-Open No. 3-122661 Japanese Patent Laid-Open No. 4-85550 Japanese Patent Publication No. 8-16804 Japanese Patent Publication No. 8-12459 Japanese Patent Publication No. 7-82250 Japanese Examined Patent Publication No. 7-72809 Japanese Patent Laid-Open No. 10-246989 JP 2002-148867 A JP 2002-287427 A

  Therefore, the present invention has been made in view of the above circumstances, and the problem is that a polyester resin formed in the presence of a specific catalyst is used as a binder resin, and a fixing device with a low fixing energy is used. The present invention provides a toner for developing an electrostatic image that is excellent in fixability and hot offset resistance and hardly causes filming.

The features of the present invention, which is a means for solving the above problems, are listed below.
The electrostatic image developing toner of the present invention is an electrostatic image developing toner comprising at least a binder resin and a colorant, and the binder resin is titanium halide, titanium diketone enolate, titanium carboxylate, titanyl carboxylate. And a polycondensation polyester resin formed in the presence of at least one titanium-containing catalyst selected from the group consisting of titanyl carboxylates, and a high softening point polyester having a softening point of 125 to 150 ° C. and a softening point of 85. A low softening point polyester of ˜105 ° C. is contained, and the difference in softening point between the high softening point polyester and the low softening point polyester is 20 ° C. to 60 ° C.
The toner for developing an electrostatic image according to the present invention is further characterized in that the titanium diketone enolate is titanium acetylacetonate.
In the electrostatic image developing toner of the present invention, the titanium carboxylate is an aromatic titanium titanium carboxylate.
In the electrostatic image developing toner of the present invention, the carboxylic acid titanyl salt is a titanyl maleate salt or a titanyl oxalate salt.
The electrostatic image developing toner of the present invention is further characterized by containing an oxycarboxylic acid complex compound as a charge control agent.
The toner for developing an electrostatic charge image of the present invention further contains 0.5 to 10% by weight of carnauba wax and / or rice wax and / or ester wax as a wax component.

  The toner cartridge of the present invention is a toner cartridge filled with an electrostatic image developing toner to be replenished to the developing device, and is filled with the electrostatic image developing toner according to any one of claims 1 to 6. It is characterized by that.

  The process cartridge of the present invention supports at least the photosensitive member and the developing device integrally, and is detachable from the main body of the image forming apparatus. In the process cartridge, the developing device is any one of claims 1 to 6. The electrostatic charge image developing toner described in 1) is used.

  The image forming method of the present invention comprises a charging step for charging a latent image carrier by applying a voltage from the outside, an exposure step for forming an electrostatic image on the charged latent image carrier, and an electrostatic image A development process for developing a toner image by developing with toner, a transfer process for applying a voltage from outside to transfer the toner image onto a transfer body or a recording material, and a cleaning process for cleaning the surface of the latent image carrier after the transfer And an image forming method comprising a fixing step of heat-fixing a toner image on a recording material, wherein the image forming method uses the electrostatic image developing toner described in any one of 1 to 6. To do.

  The image forming apparatus of the present invention includes a charging device that charges a latent image carrier by applying a voltage from the outside, an exposure device that forms an electrostatic image on the charged latent image carrier, and an electrostatic image. A developing device that forms a toner image by developing with toner, a transfer device that applies a voltage from the outside to transfer the toner image onto a transfer member or a recording material, and a cleaning device that cleans the surface of the latent image carrier after the transfer And an image forming apparatus having a fixing device that heats and fixes a toner image on a recording material, wherein the image forming apparatus uses the toner for developing an electrostatic charge image described in any one of 1 to 6. To do.

  The present invention provides an electrostatic latent image developing toner, a toner cartridge, a process cartridge, and an image formation which are excellent in fixing property and hot offset resistance and capable of obtaining a high-quality image without fogging. A method and an image forming apparatus can be provided.

The best mode for carrying out the present invention will be described below with reference to the drawings. Note that it is easy for a person skilled in the art to make other embodiments by changing or correcting the present invention within the scope of the claims, and these changes and modifications are included in the scope of the claims. The following description is an example of the best mode of the present invention, and does not limit the scope of the claims.
The toner for developing an electrostatic latent image (hereinafter simply referred to as “toner”) used in the present invention is a toner composed of at least a binder resin and a colorant, and the binder resin is titanium halide, titanium diketone enolate, A polycondensation polyester resin formed in the presence of at least one titanium-containing catalyst selected from the group consisting of titanium carboxylate, titanyl carboxylate and titanyl carboxylate, and has a softening point of 125 to 150 ° C. An electrostatic charge comprising a point polyester and a low softening point polyester having a softening point of 85 to 105 ° C, and a difference in softening point between the high softening point polyester and the low softening point polyester is 20 to 60 ° C. An image developing toner is used.

The polyester resin of the present invention is obtained by using at least one titanium-containing catalyst selected from the group consisting of titanium halide, titanium diketone enolate, titanium carboxylate, titanyl carboxylate, and titanyl carboxylate. Therefore, dispersibility of other materials such as a colorant, a charge control agent, and a wax in the toner is good, and uniform chargeability can be obtained. In addition, filming can be improved due to good dispersibility of the wax.
Furthermore, in order to improve the low temperature fixability and the hot offset resistance, it contains a high softening point polyester having a softening point of 125 to 150 ° C and a low softening point polyester having a softening point of 85 to 105 ° C. The difference between the softening points of the high softening point polyester and the low softening point polyester is preferably 20 to 60 ° C. If the difference in softening point between the high softening point polyester and the low softening point polyester is less than 20 ° C., the compatibility between the high softening point polyester and the low softening point polyester becomes high and becomes uniform. Cannot be obtained. On the other hand, if the difference between the softening points of the high softening point polyester and the low softening point polyester exceeds 60 ° C., the compatibility between the high softening point polyester and the low softening point polyester is deteriorated by kneading, resulting in poor dispersion. When the difference in softening point between the high softening point polyester and the low softening point polyester is 20 to 60 ° C., an appropriate sea-island structure can be obtained, and sufficient low-temperature fixability and hot offset resistance can be obtained. Moreover, since the viscosity at the time of kneading | mixing is obtained moderately, dispersibility becomes still more favorable and uniform charging property is obtained.

Among the titanium-containing catalysts, the titanium halide is not particularly limited, and examples thereof include dichlorotitanium, trichlorotitanium, tetrachlorotitanium, trifluorotitanium, tetrafluorotitanium, and tetrabromotitanium.
The titanium diketone enolate is not particularly limited, and examples thereof include titanium acetylacetonate, titanium diisopropoxide bisacetylacetonate, and titanyl acetylacetonate. Among these titanium diketone enolates, titanium acetylacetonate is preferable, and the reactivity is improved and the presence of low molecular weight components at the impurity level such as unreacted monomers is reduced. Therefore, when used as a binder resin in a toner, filming due to these substances can be suppressed. As a result, it is possible to suppress a decrease in the charge amount and the fusion of the photoconductor due to the carrier spent in long-term use.

  Although it does not specifically limit as carboxylate titanium, For example, C1-C32 aliphatic carboxylate titanium, C7-38 aromatic carboxylate titanium, etc. are mentioned. In the case of titanium polycarboxylate having a valence of 2 or more, the number of carboxyl groups coordinated to titanium may be one or more, and a free carboxyl group may exist without being coordinated to titanium. Although it does not specifically limit as C1-C32 aliphatic carboxylate titanium, For example, aliphatic monocarboxylic acid titanium, aliphatic dicarboxylic acid titanium, aliphatic tricarboxylic acid titanium, and 4-8 valent or more aliphatic polycarboxylic acid. Examples thereof include titanium carboxylate. The aliphatic monocarboxylic acid titanium is not particularly limited, and examples thereof include titanium formate, titanium acetate, titanium propionate, and titanium octoate. The aliphatic dicarboxylic acid titanium is not particularly limited, and examples thereof include titanium oxalate, titanium succinate, titanium maleate, titanium adipate, and titanium sebacate. Although it does not specifically limit as aliphatic tricarboxylic acid titanium, For example, hexane tricarboxylic acid titanium, isooctane tricarboxylic acid titanium, etc. are mentioned. Although it does not specifically limit as aliphatic tricarboxylic acid titanium, For example, octane tetracarboxylic acid titanium, decane tetracarboxylic acid titanium, etc. are mentioned.

The aromatic carbonic acid titanium having 7 to 38 carbon atoms is not particularly limited. For example, aromatic monocarboxylic acid titanium, aromatic dicarboxylic acid titanium, aromatic tricarboxylic acid titanium, and tetravalent to octavalent or higher aromatic polycarboxylic acid. Examples thereof include titanium carboxylate. The aromatic monocarboxylic acid titanium is not particularly limited, and examples thereof include titanium benzoate. The aromatic titanium dicarboxylate is not particularly limited. For example, titanium phthalate, titanium terephthalate, titanium isophthalate, titanium 1,3-naphthalenedicarboxylate, titanium 4,4-biphenyldicarboxylate, 2,5-toluenedicarboxylic acid Examples thereof include titanium oxide and titanium anthracene dicarboxylate. Although it does not specifically limit as aromatic tricarboxylic acid titanium, For example, trimellitic acid titanium, 2,4,6- naphthalene tricarboxylic acid titanium, etc. are mentioned. Although it does not specifically limit as aromatic polycarboxylic acid titanium, For example, pyromellitic acid titanium, 2,3,4,6- naphthalene tetracarboxylic acid titanium etc. are mentioned.
Among these titanium carboxylates, titanium aromatic carboxylates having 7 to 38 carbon atoms are preferable, titanium titanium aromatic dicarboxylates are preferable, the reactivity is improved, and the presence of low molecular weight components such as unreacted monomers is reduced. To do. Therefore, when used as a binder resin in a toner, filming due to these substances can be suppressed. As a result, it is possible to suppress a decrease in the charge amount and the fusion of the photoconductor due to the carrier spent in long-term use.

Although it does not specifically limit as carboxylate titanyl, For example, C1-C32 aliphatic carboxylate titanyl, C7-38 aromatic carboxylate titanyl, etc. are mentioned. In the case of titanyl polycarboxylate having a valence of 2 or more, the number of carboxyl groups coordinated to titanium may be one or more, and a free carboxyl group may be present without being coordinated to titanium.
Although it does not specifically limit as a C1-C32 aliphatic carboxylate titanyl, For example, an aliphatic monocarboxylic acid titanyl, an aliphatic dicarboxylic acid titanyl, an aliphatic tricarboxylic acid titanyl, and a 4- to 8-valent or more aliphatic polycarboxylic acid. And titanyl carboxylate.
The aliphatic monocarboxylic acid titanyl is not particularly limited, and examples thereof include titanyl formate, titanyl acetate, titanyl propionate, and titanyl octoate. The aliphatic dicarboxylic acid titanyl is not particularly limited, and examples thereof include titanyl oxalate, titanyl succinate, titanyl maleate, titanyl adipate, and titanyl sebacate. Although it does not specifically limit as aliphatic tricarboxylic acid titanyl, For example, hexane tricarboxylic acid titanyl, isooctane tricarboxylic acid titanyl, etc. are mentioned. Although it does not specifically limit as a 4-8 valent or more aliphatic polycarboxylic acid titanyl, For example, an octane tetracarboxylic-acid titanyl, a decane tetracarboxylic-acid titanyl, etc. are mentioned.

Although it does not specifically limit as C7-38 aromatic carboxylic acid titanyl, For example, aromatic monocarboxylic acid titanyl, aromatic dicarboxylic acid titanyl, aromatic tricarboxylic acid titanyl, and 4-8 valent or more aromatic polycarboxylic acid. And titanyl carboxylate.
The titanyl aromatic monocarboxylate is not particularly limited, and examples thereof include titanyl benzoate. Although it does not specifically limit as aromatic dicarboxylate titanyl, For example, titanyl phthalate, titanyl terephthalate, titanyl isophthalate, titanyl 1,3-naphthalenedicarboxylate, titanyl 4,4-biphenyl dicarboxylate, 2,5-toluene dicarboxylic Examples thereof include titanyl acid and titanyl anthracene dicarboxylate. The aromatic tricarboxylic acid titanyl is not particularly limited, and examples thereof include titanyl trimellitic acid and titanyl 2,4,6-naphthalene tricarboxylic acid. Although it does not specifically limit as 4-8 valence or more aromatic polycarboxylic acid titanyl, For example, pyromellitic acid titanyl, 2,3,4,6- naphthalene tetracarboxylic acid titanyl etc. are mentioned.

  Although it does not specifically limit as carboxylic acid titanyl salt, For example, an aliphatic dicarboxylic acid titanyl, an aliphatic tricarboxylic acid titanyl, 4-8 valent or more aliphatic polycarboxylic acid titanyl, aromatic dicarboxylic acid titanyl, aromatic tricarboxylic acid Alkali metal (lithium, sodium, potassium, etc.) or alkaline earth metal (magnesium, calcium, barium, etc.) salt of titanyl, or titanyl carboxylate listed in titanyl of 4-8 or higher aromatic polycarboxylic acid Etc. Of these carboxylic acid titanyl salts, maleic acid titanyl salt and oxalic acid titanyl salt are preferred, and the reactivity is improved and the presence of low molecular weight components at the impurity level such as unreacted monomers is reduced. Therefore, when used as a binder resin in a toner, filming due to these substances can be suppressed. As a result, it is possible to suppress a decrease in the charge amount and the fusion of the photoconductor due to the carrier spent in long-term use.

The amount of titanium-containing catalyst used is not particularly limited, but the lower limit is preferably 0.01%, more preferably 0.02%, based on the total weight of the polyol and polycarboxylic acid used to obtain the polyester resin. 0.03% is particularly preferred and 0.05% is most preferred. The upper limit is preferably 5%, more preferably 2%, particularly preferably 1.5%, and most preferably 0.8%. When it is 0.01% or more, the effect as a polycondensation catalyst is sufficiently obtained, and when it is 5% or less, high catalytic action is obtained according to the amount of catalyst. In addition, when the amount is within the above-mentioned range of the catalyst amount, the necessary properties of the toner using the toner binder made of the polyester resin to be obtained become better. In the above and below, “%” means “% by weight” unless otherwise specified.
Among these titanium-containing catalysts, preferred are titanium diketone enolate, titanium carboxylate, titanyl carboxylate and combinations thereof, more preferably titanium diketone enolate, aromatic carboxylic acid titanium, aliphatic carboxylic acid. Acid titanyl salts, aromatic carboxylic acid titanyl salts and combinations thereof, more preferably, among titanium acetylacetonate, aromatic dicarboxylic acid titanium, and carboxylic acid titanyl salts, alkali metal salts and combinations thereof, particularly preferable. Is titanium terephthalate, titanium isophthalate, titanium orthophthalate, titanyl oxalate, titanyl maleate and combinations thereof, most preferably titanium terephthalate, potassium titanyl oxalate and combinations thereof.

In the toner of the present invention, polarity control can be blended in order to control polarity. Examples of polarity control agents in this case include nigrosine dyes, quaternary ammonium salts, amino group-containing polymers, metal-containing azo dyes, salicylic acid complex compounds, phenol compounds, and the like. A known compound can be used, but a compound represented by the following general formula (1) is preferred from the viewpoint of charge imparting ability.

Furthermore, the following specific examples are preferable from the viewpoint of charge application.

When the present invention is used for a two-component developing monochrome toner, carbon black can be used as a colorant. As a colorant, a titanium component measured with a wavelength dispersive X-ray fluorescence apparatus is converted to Fe atom in terms of Ti atom. By using a black iron oxide compound contained in an amount of 10 to 45% by weight, the thermal conductivity is increased, so that the low-temperature fixability is further improved.
The structure of the black oxide compound is preferably a polycrystalline particle powder containing a Fe ₂ O ₃ —FeTiO ₃ solid solution because it is black and weak in magnetism.
The black iron oxide compound according to the present invention is obtained by reducing, for example, magnetite particle powder whose particle surface is coated with a titanium compound, mixed powder of magnetite particle powder and titanium compound, or hematite particle powder whose particle surface is coated with a titanium compound. Each of the obtained reduced powders is obtained by a method of heating and firing at a temperature of 700 ° C. or higher in a non-oxidizing atmosphere and then pulverizing. When magnetite particle powder whose particle surface is coated with a titanium compound is used as a raw material, it is a preferable method from the viewpoint of easily obtaining particles having a small magnetization value and non-magnetism.

The magnetite particle powder and the hematite particle powder may be particles in any form such as granular, spherical, and needle-like, and particles having a size of about 0.03 to 1.5 μm can be used. There is a correlation between the size of the raw material particles and the size of the product particles. When small raw material particles are used, small product particles tend to be obtained, and when large raw material particles are used, large product particles tend to be obtained. It is in.
As the titanium compound, any of hydrated oxide, hydroxide and oxide of titanium can be used. When mixing with magnetite particle powder, it is preferable to use a water-soluble titanium compound. The amount of the titanium compound is preferably in the range of 10 to 45 wt. When the amount is less than 10% by weight, the magnetization value of the obtained black pigment particle powder is increased, the developing ability of the toner is lowered, and the image density is lowered. If it exceeds 45% by weight, non-magnetic black pigment particle powder can be obtained. However, since the amount of TiO ₂ produced increases, the L value (lightness) increases and the toner coloring power decreases. The ratio with respect to Fe atoms in terms of Ti atoms can be determined from the ratio of the obtained main peak using a fluorescent X-ray analyzer.

The present invention relates to a polycondensation polyester resin formed in the presence of a titanium-containing catalyst as a binder resin, and as a colorant, a titanium component measured with a wavelength dispersive fluorescent X-ray apparatus with respect to Fe atoms in terms of Ti atoms. By using a black iron oxide compound containing 10 to 45% by weight, the disadvantages of the prior art are improved. That is, in the present invention, even when a black iron oxide compound having a particle size larger than that of carbon black is used, the dispersibility of the black iron oxide compound is good. And does not adversely affect heat storage stability.
The mechanism by which the dispersibility of the black iron oxide compound is improved in the present invention is not clear, but the polycondensation polyester resin formed in the presence of the titanium-containing catalyst and the titanium component are converted into Fe atoms in terms of Ti atoms. By using the black iron oxide compound contained in an amount of 10 to 45% by weight, it is considered that the affinity of the black iron oxide compound for the resin is increased and the dispersibility is improved. From the viewpoint of dispersibility, the titanium component is preferably contained in an amount of 10 to 45% by weight with respect to Fe atoms in terms of Ti atoms.

The saturation magnetization σ s of the toner measured in a magnetic field of 398 kA / m (5 kOe) is preferably 0.1 to 5.0 emu / g. When the saturation magnetization of the toner is 5.0 emu / g or more, the holding force with the toner carrier having a built-in magnet such as a magnetic sleeve or a magnetic brush becomes strong, and the developability to the photoreceptor deteriorates. When it is less than 0.1 emu / g, the holding force with the toner carrier is weakened, and the toner scattering and the soiling are worsened.
To measure the saturation magnetization of the toner, when a magnetic field measuring device BHU-60 manufactured by Riken Denshi Co., Ltd. was used and the magnetic field was swept up to 398 kA / m (5 kOe) in a toner filled in a cell having an inner diameter of 7 mmφ and a height of 10 mm. The saturation magnetization was obtained from the hysteresis curve.
The content of the black iron oxide compound is 15 to 40 parts by weight, preferably 20 to 30 parts by weight. When the amount is less than 15 parts by weight, the coloring power of the toner is insufficient, and the toner has a reddish color. Further, the fixing temperature is not sufficiently lowered. In the case of 40 parts by weight or more, the specific gravity of the toner becomes too large and the developing ability is lowered.

In the present invention, it is preferable that at least a part of the polyester resin is modified with polyepoxide.
Examples thereof include a polyester resin that is a polycondensate of polyol and polycarboxylic acid, and a modified polyester resin that is obtained by further reacting a polyepoxide or the like with a polyester resin that is a polycondensate of polyol and polycarboxylic acid. Polyester resins, modified polyester resins, and the like may be used alone or in combination of two or more.
Although it does not specifically limit as a polyol, For example, diol, a trihydric or more polyol, etc. are mentioned. Although it does not specifically limit as polycarboxylic acid, For example, dicarboxylic acid, trivalent or more polycarboxylic acid, etc. are mentioned.

Although it does not specifically limit as a polyester resin which comprises the toner binder of this invention, For example, the following are specifically mentioned, These can also be used together.
Linear polyester: Linear polyester resin using diol and dicarboxylic acid Non-linear polyester: Non-linear polyester resin using polyol and / or polycarboxylic acid together with diol and dicarboxylic acid (Yl): (X2) Modified polyester resin reacted with polyepoxide.
The diol is not particularly limited. For example, a diol having a hydroxyl value of 180 to 1900 mg KOH / g, specifically, an alkylene glycol having 2 to 12 carbon atoms (ethylene glycol, 1,2-propylene glycol, 1,3-propylene). Glycol, 1,4-butylene glycol and 1,6-hexanediol); alkylene ether glycol (diethylene glycol, triethylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol and polybutylene glycol); alicyclic diol (1 , 4-cyclohexanedimethanol and hydrogenated bisphenol A); bisphenols (such as bisphenol A, bisphenol F and bisphenol S); Adducts such as ethylene oxide (hereinafter abbreviated as EO), propylene oxide (hereinafter abbreviated as PO) and butylene oxide (hereinafter abbreviated as BO)]; alkylene oxides having 2 to 4 carbon atoms of the above bisphenols ( EO, PO, and BO)) and the like.
Among these, preferred are alkylene glycols having 2 to 12 carbon atoms, alkylene oxide adducts of bisphenols, and combinations thereof, and particularly preferred are alkylene oxide adducts of bisphenols, and those having 2 carbon atoms. Use in combination with ˜12 alkylene glycols. In the above and below, the hydroxyl value and the acid value are measured by the method defined in JIS K 0070.

The trihydric or higher polyol (H) is not particularly limited. For example, polyols having a hydroxyl value of 150 to 1900 mgKOH / g, specifically, 3 to 8 or higher aliphatic polyhydric alcohols (glycerin, trie Tyrolethane, trimethylolpropane, pentaerythritol, sorbitol, etc.); adducts of the above aliphatic polyhydric alcohols with 2 to 4 carbon oxides (such as EO, PO and BO); trisphenols (such as trisphenol PA) A novolak resin (such as phenol novolak and cresol novolak); an adduct of C 2-4 alkylene oxide (such as EO, PO and BO) of the above trisphenol; a C 2-4 alkylene oxide of the above novolac resin (EO) , PO, BO, etc.) That.
Among these, preferred are aliphatic polyhydric alcohols having 3 to 8 valences or higher and alkylene oxide adducts of novolak resins, and particularly preferred are alkylene oxide adducts of novolak resins.

Although it does not specifically limit as dicarboxylic acid, For example, dicarboxylic acid with an acid value of 180-1250 mgKOH / g, specifically, C4-C36 alkylene dicarboxylic acid (succinic acid, adipic acid, sebacic acid, dodecenyl succinic acid, etc.) : C4-C36 alkenylene dicarboxylic acid (maleic acid, fumaric acid, etc.); C8-36 aromatic dicarboxylic acid (phthalic acid, isophthalic acid, terephthalic acid, naphthalenedicarboxylic acid, etc.), etc. are mentioned. Of these, preferred are alkenylene dicarboxylic acids having 4 to 20 carbon atoms and aromatic dicarboxylic acids having 8 to 20 carbon atoms. Moreover, even if these use together 2 or more types, there is no problem. In addition, as the dicarboxylic acid, acid anhydrides as described above or lower (1 to 4 carbon atoms) alkyl esters (methyl ester, ethyl ester, isopropyl ester, etc.) may be used.
Although it does not specifically limit as polycarboxylic acid more than trivalence, For example, polycarboxylic acid of acid value 150-1250 mgKOH / g, specifically, C9-C20 aromatic polycarboxylic acid (trimellitic acid, pyromellitic acid) Merit acid, etc.); vinyl polymer of unsaturated carboxylic acid (styrene / maleic acid copolymer, styrene / acrylic acid copolymer, α-olefin / maleic acid copolymer, styrene / fumaric acid copolymer, etc.), etc. Is mentioned. Among these, preferred are aromatic polycarboxylic acids having 9 to 20 carbon atoms, and particularly preferred are trimellitic acid and pyromellitic acid. In addition, as a polycarboxylic acid (J) more than trivalence, you may use the acid anhydride of the above-mentioned thing, or lower (C1-C4) alkylester (Methyl ester, ethyl ester, isopropyl ester, etc.).

Moreover, hydroxycarboxylic acid can also be copolymerized with a diol, a polyol, dicarboxylic acid, and polycarboxylic acid.
Although it does not specifically limit as hydroxycarboxylic acid, For example, a hydroxy stearic acid, hydrogenated castor oil fatty acid, etc. are mentioned.
The polyepoxide is not particularly limited. For example, polyglycidyl ether [ethylene glycol diglycidyl ether, tetramethylene glycol diglycidyl ether, bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, glycerin triglycidyl ether, pentaerythritol tetraglycidyl ether, Phenol novolac (average polymerization degree 3 to 60) glycidyl etherified product, etc.]; diene oxide (pentadiene dioxide, hexadiene dioxide, etc.) and the like. Among these, polyglycidyl ether is preferable, and ethylene glycol diglycidyl ether and bisphenol A diglycidyl ether are more preferable. The number of epoxy groups per molecule of the polyepoxide is preferably 2 to 8, more preferably 2 to 6, and particularly preferably 2 to 4. Although it does not specifically limit as an epoxy equivalent of polyepoxide, Preferably it is 50-500. The lower limit is more preferably 70, particularly preferably 80, and the upper limit is more preferably 300, particularly preferably 200. When the number of epoxy groups and / or the epoxy equivalent is within the above range, both developability and fixability are improved. It is more preferable if the above-mentioned ranges of the number of epoxy groups per molecule and the range of epoxy equivalent are satisfied at the same time.

The ratio of the polyol and the polycarboxylic acid is preferably 2/1 to 1/2, more preferably 1.5 / 1 to 1 as an equivalent ratio [OH] / [COOH] of the hydroxyl group [OH] and the carboxyl group [COOH]. 1 / 1.3, particularly preferably 1.3 / 1 to 1 / 1.2. The types of polyol and polycarboxylic acid to be used are preferably selected in consideration of molecular weight adjustment so that the glass transition point of the polyester toner binder finally adjusted is 40 to 90 ° C.
Although it does not specifically limit as a specific example of the linear polyester resin using diol and dicarboxylic acid, For example, the following (1)-(3) etc. are mentioned.
(1) Bisphenol A · PO2 molar adduct / terephthalic acid polycondensate.
(2) Bisphenol A · EO 4 mol adduct / bisphenol A · PO 2 mol adduct / terephthalic acid polycondensate.
(3) Bisphenol A · PO2 mol adduct / bisphenol A · PO3 mol adduct / terephthalic acid / isophthalic acid / maleic anhydride polycondensate.

Although it does not specifically limit as a specific example of (X2), For example, the following (4)-(10) etc. are mentioned.
(4) Bisphenol A · EO 2 mol adduct / bisphenol A · PO 3 mol adduct / terephthalic acid / phthalic anhydride / trimellitic anhydride polycondensate.
(5) Bisphenol A · PO2 mol adduct / bisphenol A · PO3 mol adduct / bisphenol A · EO2 mol adduct / phenol novolac PO5 mol adduct / terephthalic acid / maleic anhydride / dimethyl terephthalic acid ester / trimellitic anhydride Acid polycondensate.
(6) Bisphenol A · EO 2 mol adduct / bisphenol A · PO 2 mol adduct / terephthalic acid / trimellitic anhydride polycondensate.
(7) Bisphenol A · EO 2 mol adduct / bisphenol A · PO 2 mol adduct / terephthalic acid / maleic anhydride / trimellitic anhydride polycondensate.
(8) Bisphenol A · PO 2 mol adduct / bisphenol A · PO 3 mol adduct / terephthalic acid / isophthalic acid / maleic anhydride / trimellitic anhydride polycondensate.
(9) Bisphenol A / PO 2 mol adduct / bisphenol A / P03 mol adduct / EO adduct of phenol novolac / isophthalic acid / trimellitic anhydride polycondensate.
(10) Bisphenol A · EO 2 mol adduct / bisphenol A · PO 2 mol adduct / phenol novolak PO5 mol adduct / terephthalic acid / fumaric acid / trimellitic anhydride polycondensate.

Although it does not specifically limit as a specific example of the modified polyester resin which made the polyepoxide react with the non-linear polyester resin using polyol and / or polycarboxylic acid with diol and dicarboxylic acid, For example, the following (11)- (20).
(11) Modification obtained by reacting tetramethylene glycol diglycidyl ether with a polycondensate of bisphenol A · PO 2 mol adduct / bisphenol A · EO 2 mol adduct / phenol novolak PO5 mol adduct / terephthalic acid / dodecenyl succinic anhydride polyester.
(12) Bisphenol A · PO2 mol adduct / bisphenol A · PO3 mol adduct / bisphenol A · EO2 mol adduct / PO5 mol adduct of phenol novolac / terephthalic acid / dodecenyl succinic anhydride heavy bond ethylene glycol diglycidyl ether Modified polyester obtained by reacting
(13) Reaction of bisphenol A diglycidyl ether with bisphenol A · PO 2 mol adduct / bisphenol A · PO 3 mol adduct / phenol novolak EO adduct / isophthalic acid / maleic anhydride / trimellitic anhydride polycondensate The resulting modified polyester.
(14) Bisphenol A / PO 2 mol adduct / Bisphenol A / PO 3 mol adduct / Bisphenol A / EO 2 mol adduct / EO adduct of phenol novolac / Terephthalic acid / Isophthalic acid / Trimellitic anhydride polycondensate A modified polyester obtained by reacting diglycidyl ether.
(15) Bisphenol A / PO 2 mol adduct / bisphenol A / PO 3 mol adduct / bisphenol A / EO 2 mol adduct / phenol novolak PO5 mol adduct / terephthalic acid / isophthalic acid / maleic anhydride / trimellitic anhydride heavy A modified polyester obtained by reacting a condensate with bisphenol A diglycidyl ether.
(16) A modified polyester obtained by reacting ethylene glycol diglycidyl ether with bisphenol A · PO 3 mol adduct / phenol novolac PO 5 mol adduct / terephthalic acid / fumaric acid / trimellitic anhydride polycondensate.
(17) A modified polyester obtained by reacting tetramethylene glycol diglycidyl ether with a polycondensate of bisphenol A · PO 2 mol adduct / phenol novolac PO 5 mol adduct / terephthalic acid / dodecenyl succinic anhydride / trimellitic anhydride.
(18) Modified polyester obtained by reacting bisphenol A · PO2 molar adduct / bisphenol A · EO2 molar adduct / phenol novolak EO adduct / terephthalic acid / trimellitic anhydride polycondensate with ethylene glycol diglycidyl ether .
(19) Modification obtained by reacting bisphenol A diglycidyl ether with bisphenol A · PO2 mol adduct / bisphenol A · PO3 mol adduct / PO5 mol adduct of phenol novolac / terephthalic acid / trimellitic anhydride polycondensate polyester.
(20) A modified polyester obtained by reacting a phenol novolac glycidyl etherified product with a bisphenol A · PO 2 mol adduct / bisphenol A · EO 2 mol adduct / terephthalic acid / trimellitic anhydride polycondensate.

The toner binder is required to have different physical properties for full color and monochrome use, and the design of the polyester resin is also different. A high gloss image is required for full color, so it is necessary to use a low-viscosity binder. However, for monochrome use, gloss is not particularly required and hot offset properties are important, so it is necessary to use a highly elastic binder.
Non-linear polyesters, modified polyesters, and mixtures thereof are preferred for obtaining high hot offset resistance useful for monochrome copying machines and the like. In this case, since it is preferable that it is highly elastic, as this polyester resin, what uses both polyol and polycarboxylic acid is especially preferable.
The ratio of the polyol and the polycarboxylic acid is such that the sum of the number of moles of the polyol and the polycarboxylic acid is preferably 0.1 to 40 mol% with respect to the total number of moles of the diol, polyol, dicarboxylic acid, and polycarboxylic acid. Preferably they are 0.5-5 mol%, Especially 1-20 mol%.

In the polyester resin for monochrome use, the high softening point polyester preferably contains 5 to 70% of tetrahydrofuran (THF) insoluble matter, more preferably 10 to 60%, and particularly preferably 15 to 50%. When the THF-insoluble content is 5% or more, the hot offset resistance is good, and when it is 70% or less, good low-temperature fixability is obtained. The THF-insoluble content and the THF-soluble content can be obtained by the following method.
About 0.5 g of a sample is accurately weighed into a 200 ml stoppered Meyer flask, 50 ml of THF is added, and the mixture is stirred and refluxed for 3 hours. After cooling, the insoluble matter is filtered off with a glass filter. The value (%) of THF-insoluble matter is calculated from the weight ratio of the resin content on the glass filter after vacuum drying at 80 ° C. for 3 hours and the weight of the sample. The filtrate is used as a THF soluble component for the molecular weight measurement described later.
The peak top molecular weight of the polyester resin is preferably 1000 to 30000, more preferably 1500 to 25000, and particularly 1800 to 20000 for both monochrome and full color applications. When the peak top molecular weight is 1000 or more, the heat-resistant storage stability and the powder flowability are good, and when it is 30000 or less, the pulverization property of the toner is improved and the productivity is good.

In the above and the following, the peak top molecular weight and number average molecular weight of the polyester resin are measured under the following conditions using GPC for the THF-soluble matter.
Apparatus: Tosoh HLC-8120
Column: TSKgelGMHXL (2)
TSKgelMultiporeHXL-M (1 pc.)
Measurement temperature: 40 ° C
Sample solution: 0.25% THF solution Injection volume: 100 μL
Detector: Refractive index detector Reference material: Polystyrene The molecular weight showing the maximum peak height on the obtained chromatogram is called the peak top molecular weight.
The Tg of the polyester resin is preferably 40 to 90 ° C., more preferably 50 to 80 ° C., particularly 55 to 75 ° C. for both monochrome and full color applications. When the Tg is in the range of 40 ° C. to 90 ° C., the heat resistant storage stability and the low temperature fixability become better.
In the above and the following, the Tg of the polyester resin is measured by a method (DSC method) defined in ASTM D3418-82 using DSC20, SSC / 580 manufactured by Seiko Denshi Kogyo Co., Ltd.

Although it does not specifically limit as a manufacturing method of linear polyester resin, For example, a diol, dicarboxylic acid, and a polycondensation catalyst are heated at 180 to 260 degreeC, and it dehydrates and condenses on normal pressure and / or pressure reduction conditions, and obtains a polyester resin. The method etc. are mentioned.
The production method of the non-linear polyester resin is not particularly limited. For example, diol, dicarboxylic acid, trivalent or higher polyol and polycondensation catalyst are heated to 180 ° C. to 260 ° C. and dehydrated and condensed under normal pressure and / or reduced pressure conditions. And a method of obtaining a polyester resin by further reacting a tricarboxylic or higher polycarboxylic acid. A tricarboxylic or higher polycarboxylic acid can be reacted simultaneously with a diol, a dicarboxylic acid and a trivalent or higher polyol.
Although it does not specifically limit as a manufacturing method of modified polyester resin, For example, the method etc. which obtain modified polyester resin by adding polyepoxide to non-linear polyester resin, and performing molecular extension reaction of polyester at 180 to 260 degreeC are mentioned. . In the toner binder of the present invention, two or more polyester resins can be used in combination.

In the present invention, it is preferable to contain carnauba wax and / or rice wax and / or ester wax as the wax component. Carnauba wax is a natural wax obtained from the leaves of carnauba palm, and a low acid value type from which free fatty acids are eliminated is particularly preferable because it can be uniformly dispersed in the binder resin. Rice wax is a natural wax obtained by refining crude wax produced in a dewaxing or wintering process when refining rice bran oil extracted from rice bran.
Ester wax is synthesized by ester reaction from monofunctional linear fatty acid and monofunctional linear alcohol. These wax components are used alone or in combination. The addition amount of the wax component is 0.5 to 10 parts by weight, more preferably 2 to 8 parts by weight. In the present invention, other wax components of carnauba wax, rice wax, and synthetic ester wax can be used. For example, polyolefin wax such as polypropylene wax and polyethylene wax. The toner of the present invention can use other resins than the polyester resin. As other resins used in the present invention, conventionally known resins are used. For example, styrene, poly-α-still styrene, styrene-chlorostyrene copolymer, styrene-propylene copolymer, styrene-butadiene copolymer, styrene-vinyl chloride copolymer, styrene-vinyl acetate copolymer, styrene -Styrene such as maleic acid copolymer, styrene-acrylic acid ester copolymer, styrene-methacrylic acid ester copolymer, styrene-α-chloroacrylic acid methyl copolymer, styrene-acrylonitrile-acrylic acid ester copolymer Resin (monopolymer or copolymer containing styrene or styrene-substituted product), epoxy resin, vinyl chloride resin, rosin-modified maleic acid resin, phenol resin, polyethylene resin, polypropylene resin, petroleum resin, polyurethane resin, ketone resin, Ethylene-ethyl acrylate copolymer Examples thereof include coalescence, xylene resin, and polyvinyl butyrate resin. Moreover, the manufacturing method of these resin is not specifically limited, either bulk polymerization, solution polymerization, emulsion polymerization, and suspension polymerization can be used.

The toner production method of the present invention may be a conventionally known method, in which a resin component, a colorant, a wax component, and in some cases, a charge control agent, etc. are mixed using a mixer or the like, and a heat roll, an extruder, etc. After kneading using a kneader, the mixture is cooled and solidified, pulverized by pulverization with a jet mill or the like, and then classified.
Other additives may be added to the toner as necessary. Examples of the additive include silica, aluminum oxides, and titanium oxides. When the main purpose is to impart high fluidity, the average primary particle diameter of the hydrophobized silica or rutile type fine particle titanium oxide is suitably 0.001 to 1 μm, preferably 0.005 to 0.1 μm. In particular, organosilane surface-treated silica or titania is preferable, and is usually used in a proportion of 0.1 to 5% by weight, preferably 0.2 to 2% by weight.

  Further, for example, when the toner of the present invention is used as a two-component dry toner, the carrier used by mixing is mainly composed of glass, iron, ferrite, nickel, zircon, silica, etc., and has a particle size of 30 to 1000 μm. It is possible to appropriately select and use a powder of a certain degree, or a powder coated with a styrene-acrylic resin, a silicon resin, a polyamide resin, a polyvinylidene fluoride resin, or the like using the powder as a core material.

Since this toner has excellent dispersibility of wax and is excellent in fluidity, it can be sufficiently stored in a cartridge container, and the process cartridge is configured to convey toner from the cartridge container to the developing unit. Also suitable for 90.
FIG. 1 is a schematic view showing the configuration of the process cartridge of the present invention.
Examples of the process cartridge 90 include a toner cartridge 56 that fills toner, and a toner cartridge 56 that includes at least the photosensitive member 60 and the developing device 50 and fills toner in a toner container of the developing device. Usually, the toner cartridge 56 or the process cartridge 90 is mounted on the image forming apparatus 100 to form an image.

FIG. 2 is a schematic diagram showing the configuration of the image forming apparatus of the present invention.
The toner of the present invention can be used in an image forming apparatus. When the image forming operation is started, the photosensitive member 60 rotates in the clockwise direction. Then, the surface of the photoreceptor 60 is uniformly charged by the charging roller 70. Then, a laser beam corresponding to the image is exposed to the photosensitive member 60 by the exposure device 110 to form a latent image corresponding to the image data. When the photosensitive member 60 rotates and reaches the position of the developing device 50, it is developed with toner and becomes a toner image.
On the other hand, the transfer paper is fed from the paper feed cassette 130 by the separation paper feed unit, and is electrostatically attracted onto the transferred transfer paper by the transfer device 120. The transfer paper P is heated and pressed by the fixing device 140 to melt and fix the toner image, and is discharged onto a paper discharge tray of the image forming apparatus 100.
By using the above-described toner in the developing device 10, the charge rising of the toner can be accelerated by mixing and stirring with a small force, the toner charge amount distribution is narrow, the charge amount uniformity is high, and the fog is high. A high quality image can be obtained. In addition, since the lower limit of fixing is low, the power consumption of the fixing device 140 is small, and the running cost can be reduced. Further, by reducing the filming on the photoconductor 60 and the carrier, it is possible to lengthen the maintenance period of the apparatus by extending the usable period.

Hereinafter, the present invention will be described more specifically, but the present invention is not limited thereto. Hereinafter, a part shows a weight part. The softening point is measured by the following method.
(Measurement method of softening point)
Using a flow tester, the temperature is raised at a constant speed under the following conditions, and the temperature at which the outflow amount becomes 1/2 is defined as the softening point.
Apparatus: Shimadzu Corporation flow tester CFT-500D
Load: 20 kgf / cm ²
Die: 1mmΦ-1mm
Temperature increase rate: 6 ° C / min
Sample amount: 1.0 g

(Synthesis of polyester resin)
[Synthesis of linear polyester resin]
<Linear polyester: A1>
In a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen introduction tube, 400 parts of bisphenol A / PO2 molar adduct, 350 parts of bisphenol A / PO3 molar adduct, 250 parts of terephthalic acid, 85 parts of isophthalic acid, maleic anhydride 10 And 2 parts of titanium acetate as a polycondensation catalyst were added and reacted at 220 ° C. for 10 hours while distilling off the water produced under a nitrogen stream. Next, the reaction was carried out under a reduced pressure of 5-20 mmHg, and when the acid value reached 5, it was taken out, cooled to room temperature and pulverized to obtain a linear polyester resin A1. A1 did not contain THF-insoluble matter, and its acid value was 6, the hydroxyl value was 20, Tg was 59 ° C, and the softening point was 105 ° C.

<Linear polyester: A2>
The reaction was carried out in the same manner as A1 except that the polycondensation catalyst was replaced with 3 parts of isooctanetricarboxylic acid, cooled to room temperature and pulverized to obtain a linear polyester resin A2. A2 contained no THF-insoluble matter, and had an acid value of 9, a hydroxyl value of 23, a Tg of 59 ° C., and a softening point of 85 ° C.

<Linear polyester: A3>
In a reaction vessel equipped with a cooling tube, a pulverizer and a nitrogen introduction tube, 410 parts of bisphenol A / PO 2 mol adduct, 300 parts of bisphenol A / PO 3 mol adduct, 110 parts of terephthalic acid, 100 parts of isophthalic acid, maleic anhydride 15 parts and 2 parts of titanium terephthalate as a polycondensation catalyst were added and reacted at 220 ° C. for 10 hours while distilling off the water produced in a nitrogen stream. Subsequently, it was made to react under the reduced pressure of 5-20 mmHg, and when the acid value became 2 or less, it took out, cooled to room temperature, and pulverized to obtain a linear polyester resin A3. A3 contained no THF-insoluble matter, and had an acid value of 20, a hydroxyl value of 40, a Tg of 61 ° C., and a softening point of 90 ° C.

<Linear polyester: A4>
Except that the polycondensation catalyst was replaced with 3 parts of potassium titanyl oxalate, the reaction was carried out in the same manner as A3, cooled to room temperature and pulverized to obtain a non-linear polyester resin A4. A4 contained no THF-insoluble matter, and had an acid value of 17, a hydroxyl value of 35, a Tg of 61 ° C., and a softening point of 100 ° C.

[Synthesis of linear polyester resin for comparison]
<Linear polyester for comparison>
The reaction was carried out in the same manner as A1 except that the polycondensation catalyst was replaced with 2 parts of titanium tetrabutoxide. Since the reaction stopped due to catalyst deactivation and the generated water could not be distilled off, 1.5 parts of titanium tetrabutoxide was added five times during the reaction. The desired polycondensate could not be obtained. Further, the reaction product was strongly colored purple-brown.

<Linear polyester for comparison: A'1>
The reaction was carried out in the same manner as A1 except that the polycondensation catalyst was replaced with 2 parts of titanium tetraglycoxide. Since the reaction rate was slow, a linear polyester resin A′1 for comparison was obtained by reacting under normal pressure for 20 hours and under reduced pressure for 6 hours. A′1 is a purple-brown resin, containing no THF-insoluble matter, having an acid value of 5, a hydroxyl value of 11, a Tg of 58 ° C., and a softening point of 75 ° C.

[Synthesis of non-linear polyester resin]
<Non-linear polyester: B1>
In a reaction vessel equipped with a condenser, a stirrer, and a nitrogen introduction tank, 400 parts of bisphenol A / EO 2 mol adduct, 350 parts of bisphenol A / PO 3 mol adduct, 302 parts of terephthalic acid, 40 parts of phthalic anhydride and a polycondensation catalyst Then, 2.5 parts of titanium succinate was added and reacted at 230 ° C. for 10 hours while distilling off the water generated under a nitrogen stream. Next, the reaction is carried out under reduced pressure of 5 to 20 mmHg. When the acid value becomes 2 or less, the mixture is cooled to 180 ° C., added with 62 parts of trimellitic anhydride, taken out after reaction for 2 hours under sealed at normal pressure, and cooled to room temperature. To obtain a non-linear polyester resin B1.
B1 contained 5% by weight of THF-insoluble matter, and had an acid value of 31, a hydroxyl value of 17, a Tg of 62 ° C., and a softening point of 125 ° C.

<Non-linear polyester: B2>
A linear polyester resin B2 was obtained by reacting in the same manner as B1 except that the polycondensation catalyst was replaced with 3.0 parts of titanium sebacate, cooling to room temperature, and pulverizing. B2 contained 25% by weight of THF-insoluble matter, and had an acid value of 25, a hydroxyl value of 25, and a softening point of 145 ° C.

<Non-linear polyester: B3>
In a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen introduction tube, 132 parts of bisphenol A / PO 2 mol adduct, 371 parts of bisphenol A / PO 3 mol adduct, 20 parts of bisphenol A / EO 2 mol adduct, phenol novolac (average) PO5 mol adduct with a polymerization degree of about 5) 125 parts, 201 parts of terephthalic acid, 25 parts of maleic anhydride, 35 parts of dimethyl terephthalic acid ester and 1.5 parts of titanium acetylacetonate as a polycondensation catalyst, nitrogen at 230 ° C. It was made to react for 10 hours, distilling off the water produced | generated under air flow. Next, the reaction is carried out under a reduced pressure of 5 to 20 mmHg. When the acid value becomes 2 or less, the mixture is cooled to 180 ° C., added with 65 parts of trimellitic anhydride, taken out after reaction for 2 hours under normal pressure sealing, and cooled to room temperature. To obtain a non-linear polyester resin B3.
The non-linear polyester resin B3 had a softening point of 130 ° C., an acid value of 30, a hydroxyl value of 17, a Tg of 57 ° C., a THF insoluble content of 15% by weight, and a softening point of 130 ° C.

[Synthesis of non-linear polyester resin for comparison]
<Non-linear polyester for comparison: B'1>
The reaction was carried out in the same manner as B1 except that the polycondensation catalyst was replaced with 2 parts of titanium tetraglycoxide. Since the reaction was stopped in the middle due to catalyst deactivation, there was a problem that the produced water could not be distilled. Therefore, 1.5 parts of titanium tetraglycoxide was added four times during the reaction, and a non-linear polyester resin for comparison was used. B'1 was obtained. B′1 is a purple-brown resin containing 2% by weight of THF insolubles, having an acid value of 33, a hydroxyl value of 16, Tg of 68 ° C., and a softening point of 115 ° C.

<Non-linear polyester for comparison: B'2>
<Non-linear polyester: B'2>
380 parts of bisphenol A / PO2 molar adduct, 360 parts of bisphenol A / PO3 molar adduct, 110 parts of terephthalic acid, 125 parts of isophthalic acid, maleic anhydride in a reactor equipped with a cooling pipe, a pulverizer and a nitrogen introduction pipe 45 parts and 2 parts of titanium tetramethoxide as a polycondensation catalyst were added and reacted at 220 ° C. for 10 hours while distilling off the water produced in a nitrogen stream. Next, the reaction is carried out under a reduced pressure of 5 to 20 mmHg, and when the acid value becomes 2 or less, it is cooled to 180 ° C., 25 parts of trimellitic anhydride is added, taken out after reaction for 2 hours under normal pressure sealing, and cooled to room temperature. By pulverizing, a non-linear polyester resin B′2 was obtained. B′2 contained 50% by weight of THF-insoluble matter, and its acid value was 25, the hydroxyl value was 35, Tg was 61 ° C., and the softening point was 160 ° C.

(Example 1)
<Toner prescription>
Linear polyester resin: A1 50 parts by weight Non-linear polyester resin: B1 33 parts by weight Carbon black 10 parts by weight Charge control agent (Spiron Black TR-H: Hodogaya Chemical) 2 parts by weight Low molecular weight polypropylene 5 parts by weight
(Weight average molecular weight: 6000)
The above formulation is kneaded using a biaxial extruder, pulverized and classified to a weight average particle size of 7.5 μm, and then 0.75 parts by weight of silica fine powder (R-972: manufactured by Client Japan) using a Henschel mixer. Were mixed to obtain a toner of the present invention. A developer having a toner concentration of 3.5 parts by weight is prepared using the present toner and a carrier in which spherical ferrite particles having an average particle diameter of 80 μm are coated with a silicone resin.

(Fixability evaluation method)
Copying is performed by changing the heater temperature in the Ricoh imageo 420 to obtain a fixed image. A fixing tape (manufactured by 3M) is applied to the fixed image (toner adhesion amount: 0.85 ± 0.05 mg / cm ² ), and after applying a certain pressure (2 kg), it is slowly peeled off. The image density before and after that is measured with a Macbeth densitometer, and the fixing rate is calculated by the following equation. Decreasing the temperature of the fixing roller step by step
Fixing rate (%) = image density after tape peeling / original image density × 100
The temperature at which the fixing rate represented by the above formula is 80% or less is defined as the fixing temperature. (Image density = before tape attachment)
(Image evaluation method)
After taking an initial image and 50000 copies of the image in a normal temperature and humidity environment (18 to 27 ° C., 30 to 70%) with Ricoh imagio 420, the fog was evaluated as an image evaluation. Fog was judged comprehensively based on the following criteria.
A: Very good. No fogging.
B: Good. Slight fog generation C: Possible. Although fogging has occurred, there is practically no problem.
D: Bad. It is terrible.

(Example 2)
(Toner prescription)
Linear polyester resin: A2 35 parts by weight Non-linear polyester resin: B2 50 parts by weight Carbon black 10 parts by weight Charge control agent (Spiron Black TR-H: Hodogaya Chemical) 2 parts by weight Low molecular weight polypropylene 3 parts by weight
(Weight average molecular weight: 6000)
The above formulation is kneaded using a biaxial extruder, pulverized and classified to a weight average particle size of 6.5 μm, and then 1.00 parts by weight of silica fine powder (R-972: manufactured by Client Japan) using a Henschel mixer. Were mixed to obtain a toner of the present invention. The evaluation results are listed at the end.

(Example 3)
(Toner prescription)
Linear polyester resin: A2 40 parts by weight Non-linear polyester resin: B3 42 parts by weight Carbon black 10 parts by weight Charge control agent (Spiron Black TR-H: Hodogaya Chemical) 3 parts by weight Low molecular weight polypropylene 5 parts by weight
(Weight average molecular weight: 6000)
The above formulation is kneaded using a biaxial extruder, pulverized and classified to a weight average particle size of 5.5 μm, and then 1.50 parts by weight of silica fine powder (R-972: manufactured by Client Japan) using a Henschel mixer. Were mixed to obtain a toner of the present invention. The evaluation results are listed at the end.

Example 4
(Toner prescription)
Linear polyester resin: A3 40 parts by weight Non-linear polyester resin: B2 42 parts by weight Carbon black 10 parts by weight Charge control agent (Spiron Black TR-H: Hodogaya Chemical) 3 parts by weight Low molecular polypropylene 5 parts by weight (weight average) Molecular weight: 6000)
The above formulation was kneaded using a biaxial extruder, pulverized and classified to a weight average particle size of 6.5 μm, and then 1.25 parts by weight of silica fine powder (R-972: manufactured by Client Japan) using a Henschel mixer. Were mixed to obtain a toner of the present invention. The evaluation results are listed at the end.

(Example 5)
(Toner prescription)
Linear polyester resin: 42 parts by weight of A4 Non-linear polyester resin: 42 parts by weight of B3 10 parts by weight of carbon black Charge control agent (Spiron Black TR-H: Hodogaya Chemical) 1 part by weight Low molecular weight polypropylene 5 parts by weight
(Weight average molecular weight: 6000)
The above formulation is kneaded using a biaxial extruder, pulverized and classified to a weight average particle size of 7.5 μm, and then 0.75 parts by weight of silica fine powder (R-972: manufactured by Client Japan) using a Henschel mixer. Were mixed to obtain a toner of the present invention. The evaluation results are listed at the end.

(Example 6)
(Toner prescription)
Linear polyester resin: A4 40 parts by weight Nonlinear polyester resin: B3 43 parts by weight Carbon black 10 parts by weight Charge control agent: 3,5-di-tert-butylsalicylic acid compound 2 parts by weight Low molecular weight polypropylene 5 parts by weight
(Weight average molecular weight: 6000)
The above formulation is kneaded using a biaxial extruder, pulverized and classified to a weight average particle size of 7.5 μm, and then 0.75 parts by weight of silica fine powder (R-972: manufactured by Client Japan) using a Henschel mixer. Were mixed to obtain a toner of the present invention. The evaluation results are listed at the end.

(Example 7)
(Toner prescription)
Linear polyester resin: A4 40 parts by weight Non-linear polyester resin: B3 43 parts by weight Carbon black 10 parts by weight Charge control agent: 3,5-di-tert-butylsalicylic acid compound 2 parts by weight Carnauba wax 5 parts by weight
(Weight average molecular weight: 3500)
The above formulation is kneaded using a biaxial extruder, pulverized and classified to a weight average particle size of 7.5 μm, and then 0.75 parts by weight of silica fine powder (R-972: manufactured by Client Japan) using a Henschel mixer. Were mixed to obtain a toner of the present invention. The evaluation results are listed at the end.

(Example 8)
(Toner prescription)
Linear polyester resin: A4 40 parts by weight Nonlinear polyester resin: B3 43 parts by weight Carbon black 10 parts by weight Charge control agent: 3,5-di-tert-butylsalicylic acid compound 2 parts by weight Ester wax 5 parts by weight
(Weight average molecular weight: 2500)
The above formulation is kneaded using a biaxial extruder, pulverized and classified to a weight average particle size of 7.5 μm, and then 0.75 parts by weight of silica fine powder (R-972: manufactured by Client Japan) using a Henschel mixer. Were mixed to obtain a toner of the present invention. The evaluation results are listed at the end.

(Comparative Example 1)
(Toner prescription)
Linear polyester resin: A′1 40 parts by weight Nonlinear polyester resin: B′143 parts by weight Carbon black 10 parts by weight Charge control agent: 3,5-di-tert-butylsalicylic acid compound 2 parts by weight Ester wax 5 parts by weight
(Weight average molecular weight: 2500)
The above formulation is kneaded using a biaxial extruder, pulverized and classified to a weight average particle size of 6.5 μm, and then 1.00 parts by weight of silica fine powder (R-972: manufactured by Client Japan) using a Henschel mixer. Were mixed to obtain a toner of the present invention. The evaluation results are listed at the end.

(Comparative Example 2)
(Toner prescription)
Linear polyester resin: A′1 40 parts by weight Nonlinear polyester resin: B′2 43 parts by weight Carbon black 10 parts by weight Charge control agent: 3,5-di-tert-butylsalicylic acid compound 2 parts by weight Ester wax 5 parts by weight Part
(Weight average molecular weight: 2500)
The above formulation is kneaded using a biaxial extruder, pulverized and classified to a weight average particle size of 6.5 μm, and then 1.00 parts by weight of silica fine powder (R-972: manufactured by Client Japan) using a Henschel mixer. Were mixed to obtain a toner of the present invention. Shown in the evaluation result list.

表１から明らかなように、本発明のトナーは定着性、耐ホットオフセット性に優れ、かぶりが無い高品位な画像を得られることがわかる。

As is apparent from Table 1, it can be seen that the toner of the present invention is excellent in fixability and hot offset resistance, and can provide a high-quality image without fogging.

It is the schematic which shows the structure of the process cartridge of this invention. 1 is a schematic diagram illustrating a configuration of an image forming apparatus of the present invention.

Explanation of symbols

50 Developing Device 60 Photoconductor 70 Charging Device 80 Cleaning Device 90 Process Cartridge 100 Image Forming Device 110 Exposure Device 120 Transfer Device 130 Paper Feed Cassette 140 Fixing Device

Claims (10)

In the electrostatic image developing toner comprising at least a binder resin and a colorant,
The binder resin is a polycondensation formed in the presence of at least one titanium-containing catalyst selected from the group consisting of titanium halides, titanium diketone enolates, titanium carboxylates, titanyl carboxylates and titanyl carboxylates. A polyester resin, comprising a high softening point polyester having a softening point of 125 to 150 ° C and a low softening point polyester having a softening point of 85 to 105 ° C;
A toner for developing an electrostatic image, wherein the difference in softening point between a high softening point polyester and a low softening point polyester is 20 to 60 ° C. The electrostatic image developing toner according to claim 1,
The toner for developing an electrostatic charge image, wherein the titanium diketone enolate is titanium acetylacetonate. The electrostatic image developing toner according to claim 1,
The toner for developing an electrostatic charge image, wherein the titanium carboxylate is an aromatic titanium carboxylate. The electrostatic image developing toner according to claim 1,
The toner for developing an electrostatic image, wherein the titanyl carboxylate is a titanyl maleate or a titanyl oxalate. The toner for developing an electrostatic charge image according to any one of claims 1 to 4,
The toner includes an oxycarboxylic acid complex compound as a charge control agent. In the electrostatic image developing toner according to any one of claims 1 to 5,
A toner for developing electrostatic images, comprising 0.5 to 10% by weight of carnauba wax and / or rice wax and / or ester wax as a wax component. In a toner cartridge filled with electrostatic charge image developing toner to be replenished to the developing device,
The toner cartridge is filled with the electrostatic image developing toner according to any one of claims 1 to 6. In a process cartridge that integrally supports at least the photosensitive member and the developing device and is detachable from the image forming apparatus main body,
A process cartridge using the toner for developing an electrostatic charge image according to any one of claims 1 to 6. A charging step for charging the latent image carrier by applying a voltage from the outside, an exposure step for forming an electrostatic image on the charged latent image carrier, and developing the electrostatic image with toner to form a toner image A developing step for forming, a transferring step for transferring a toner image onto a transfer member or a recording material by applying a voltage from the outside, a cleaning step for cleaning the surface of the latent image carrier after the transfer, and a toner image on the recording material In an image forming method having a fixing step of heat fixing to
In the image forming method, the electrostatic image developing toner described in any one of 1 to 6 is used. A charging device that charges the latent image carrier by applying a voltage from the outside, an exposure device that forms an electrostatic image on the charged latent image carrier, and a toner image obtained by developing the electrostatic image with toner. A developing device for forming, a transfer device for applying a voltage from outside to transfer the toner image onto a transfer member or a recording material, a cleaning device for cleaning the surface of the latent image carrier after the transfer, and a toner image on the recording material In an image forming apparatus having a fixing device for heat fixing to
The image forming apparatus uses the toner for developing an electrostatic charge image described in any one of 1 to 6.

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