JP2000292969A - Dry toner - Google Patents

Abstract

(57) [Summary] [PROBLEMS] Excellent in low-temperature fixing property and high-temperature offset resistance,
High image density is obtained, fog on the fixed image is small,
Provided is a dry toner which has excellent blocking resistance and does not cause fusion of a toner to a photoreceptor or winding of a fixing sheet around a fixing roller. SOLUTION: A binder resin having a carboxyl group or an acid anhydride group, and 0.001 to 30 parts by weight of an oxazoline-based compound having two or more oxazoline groups in a molecule per 100 parts by weight of the binder resin. Or 0.01 to 50 parts by weight of a resin component having two or more oxazoline groups in the molecule, and the viscoelastic properties of the toner are such that the storage elastic modulus G ′ _{75 at} 75 ° C. is 3 × 10 ⁵ to 3 × 10 ⁷ Pa, and the storage elastic modulus G ′ _{125 at} 125 ° C. is 1,000 to
A dry toner having 1 × 10 ⁵ Pa and a storage elastic modulus G ′ _{195 at} 195 ° C. of 200 to ⁴ × 10 ⁴ Pa.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a dry toner used in electrophotography, electrostatic recording, magnetic recording, toner jet, and the like. In particular, the present invention relates to a dry toner used in a fixing method of heating and fixing a visible image formed by a toner to a recording material.

[0002]

2. Description of the Related Art Conventionally, electrophotography has been disclosed in U.S. Pat. No. 2,297,691, Japanese Patent Publication No. 42-23910.
Many methods are known, as described in Japanese Patent Publication No. JP-B-43-24748 and Japanese Patent Publication No. 43-24748. Generally, using a photoconductive substance, an electric latent image is formed on a photoreceptor by various means, and then the latent image is developed with a toner to form a visible image. After a toner image is transferred onto a transfer material such as paper, the toner image is fixed on the transfer material by heat, pressure or the like to obtain a copy. Further, the toner remaining on the photoreceptor without being transferred is cleaned and removed by various methods, and then the above steps are repeated.

In recent years, devices using electrophotography have begun to be used not only as conventional copiers but also as printers for computer output. Therefore, higher reliability has been strictly pursued for devices using electrophotography, and the required performance has become more sophisticated. The equipment is no longer feasible.

In digital printers and copying of high-definition images, the most important performance required for toner is fixing performance. Regarding the fixing process,
Although various methods and devices have been developed, the most common method at present is a pressure heating method using a heat roller. Briefly, in the pressure heating method using a heat roller, the toner image surface formed on the sheet to be fixed is brought into contact with the surface of the heat roller, the surface of which is formed of a material having releasability from toner, under pressure. The toner image is fixed by heat and pressure. According to this method, since the surface of the heat roller and the toner image of the sheet to be fixed come into contact with each other under pressure, the thermal efficiency at the time of fusing the toner image onto the sheet to be fixed is extremely good, and the fixing can be performed quickly. And is very effective in high-speed electrophotographic copying machines. However, in the above method, on the other hand, since the surface of the heat roller and the toner image are in a molten state and in contact with each other under pressure, a part of the toner image adheres to the surface of the fixing roller, and the adhered substance is transferred to the fixing roller. May be stained (so-called offset phenomenon). Therefore, preventing the toner from adhering to the surface of the heat fixing roller is one of the essential conditions of the heat roller fixing method.

[0005] Recently, instead of a heat roller, a fixing device having a pressure member for opposing pressure contact with a heating member and for adhering a recording material (fixed sheet) to the heating member via a film has been developed. Although practically used, it is a device that is advantageous in terms of thermal efficiency. However, the offset development has not yet been completely prevented. On the other hand, in the latent image portion of the fine image, the lines of electric force are concentrated at the boundary between the exposed portion and the non-exposed portion, and the surface potential of the photosensitive member is apparently increased.
Particularly, in a digital printer, the latent image is ON-O
Since it is composed of the binary basic pixels of the FF, the concentration of the lines of electric force at the boundary between the exposed part and the non-exposed part is large,
In the developing step, the amount of toner per unit area developed into a line latent image formed by basic pixels is larger than the amount of toner on a normal analog image. Therefore, in the fixing of such an image, at present, a toner having better fixability and anti-offset property is required.
In addition, when used as a printer, the copy amount is 3 to 5 times that of a copier of the same level.
At the same time, high durability of development and high image stability are also required.
As described above, in recent years, the performance required for a printer has become more sophisticated, and improvements in fixability with toner, high image quality stability, and the like have become indispensable.

Therefore, as a method of preventing offset development, the roller surface is formed of a material having excellent mold releasability with respect to the toner, such as a fluororesin, in order to prevent toner from adhering to the surface of the fixing roller. At the same time, an anti-offset liquid such as silicone oil is further supplied to the surface to coat the roller surface with a thin film of the liquid. Although this method is extremely effective in preventing offset of the toner, it generates an odor when the offset preventing liquid is heated, and requires an apparatus for supplying the offset preventing liquid. Therefore, the mechanism of the copying apparatus becomes complicated, and high accuracy is required in order to obtain a result with excellent stability, so that the copying apparatus becomes expensive. Therefore, it is expected that good offset resistance and fixing property can be achieved by the toner.

In order to solve the above-mentioned problem, Japanese Patent Publication No. Sho 51
No. 23354, a crosslinking agent and a molecular weight modifier were added,
A toner using a suitably crosslinked vinyl polymer as a binder resin has been proposed. However, although the offset resistance has been improved to some extent, sufficient performance has not been obtained in terms of the fixing temperature range. In place of these vinyl resins, cross-linking is performed on a polyester resin that is essentially superior to vinyl resins in terms of low-temperature fixability,
Further, a toner to which an offset inhibitor has been added is disclosed in
208559. However,
This toner has a problem in terms of toner productivity (pulverizability). Further, in Japanese Patent Application Laid-Open No. 56-116043,
There has been proposed a toner using a resin obtained by polymerizing a vinyl monomer in the presence of a reactive polyester resin and polymerizing the polymer through a crosslinking reaction, an addition reaction, and a grafting reaction in the course of the polymerization. However, although the pulverizability is improved, it is difficult to sufficiently utilize the functions of the resins in terms of low-temperature fixability and offset prevention.

As a binder resin (binder resin), a resin crosslinked by reacting a polymer having a carboxylic acid with a metal compound has been disclosed in JP-A-57-1782.
49 and JP-A-57-178250. A method of reacting a binder resin containing a vinyl monomer and a specific monoester compound as essential constitutional units with a polyvalent metal compound and crosslinking via a metal is disclosed in JP-A-61-1.
No. 10155 and Japanese Patent Application Laid-Open No. Sho 61-110156.

Further, JP-A-63-214760,
JP-A-63-217362, JP-A-63-217
In JP-A-363-363 and JP-A-63-217364, a carboxylic acid group having a molecular weight distribution divided into two groups, a low molecular weight region and a high molecular weight region, reacts with a polyvalent metal ion. There has been proposed a method for causing crosslinking. However, in any of the methods, the reaction between the binder resin and the metal compound or the dispersion of the metal compound in the binder resin is not sufficient, and sufficient high-temperature offset resistance has not been obtained. Japanese Patent Application Laid-Open No. 2-53078 discloses a technique in which an oxazoline is contained in a polyester resin in a binder resin for a toner and a crosslinking reaction is performed on the binder resin. However, it is not sufficient, and furthermore, the toner becomes too hard and the low-temperature fixability is deteriorated, and the toner is fused to the photoconductor due to the toner being scratched. It is also easy to cause deterioration of the toner developability.

[0010] Japanese Patent Application Laid-Open Nos. 56-16144, 2-23569 and 63-127254.
JP, JP-A-3-26831, JP-A-62-9
No. 356, JP-A-3-72505, etc., by using a binder resin having two peaks in the molecular weight distribution as a toner binder resin, it is attempted to provide good low-temperature fixability and high-temperature offset resistance. A way to do that has been proposed. Although these methods show some improvement in low-temperature fixability and high-temperature offset resistance, they are still not sufficiently satisfactory. Further, the binder resin component in the toner tends to be non-uniform, which causes fogging on an image. Also, JP-A-59-214860,
128071, JP-A-1-147465,
JP-A 1-330347, JP-A 4-20230
No. 7, JP-A-4-353866 and the like disclose a toner having specific rheological properties. However, the hot offset resistance has not been satisfied.

[0011]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a dry toner which can solve the above-mentioned problems and can obtain further effects. SUMMARY OF THE INVENTION An object of the present invention is to provide a dry toner having excellent low-temperature fixability and high-temperature offset resistance. Another object of the present invention is to provide a dry toner capable of obtaining a high image density. Another object of the present invention is to provide a dry toner having less fog on a fixed image. Another object of the present invention is to provide a dry toner having excellent blocking resistance.
Another object of the present invention is to provide a dry toner which does not cause toner fusion to a photoreceptor. Another object of the present invention is to provide a dry toner which does not cause the sheet to be fixed to be wound around a fixing roller. A main object of the present invention is to provide a dry toner capable of satisfying the above objects without contradiction.

[0012]

The above objects are achieved by the present invention described below. That is, the present invention is a dry toner having toner particles containing at least a binder resin, a colorant and a resin component having an oxazoline compound or an oxazoline group, wherein the binder resin has a carboxyl group or an acid anhydride group. And the binder resin 1
The oxazoline-based compound having two or more oxazoline groups in the molecule is contained in an amount of 0.001 to 30 parts by weight or the resin component having two or more oxazoline groups in the molecule is 0% by weight. .01～50 is configured by containing parts, further, when measuring viscoelastic properties of the toner, the storage modulus G _'75 at 75 ° C. is 300, 0
The storage elastic modulus at 125 ° C. G ′ ₁₂₅ is 1,000 to 100,000 P.
a, and a storage elastic modulus G ′ _{195 at} 195 ° C. of 200 to 40,000 Pa.

Further, in the above configuration, the binder resin 100
The oxazoline-based compound having two or more oxazoline groups in the molecule is contained in an amount of 0.01 to 20 parts by weight, or such a resin component is contained in an amount of 0.05 to 20 parts by weight.
A form containing up to 30 parts by weight is preferred. Also, 75
Storage modulus G _'75 at ℃ is 1,000,000～1
0,000,000 Pa, the storage elastic modulus at 125 ° C. G ′ ₁₂₅ is 3,000 to 30,000 Pa,
And the storage modulus G _'195 at 195 ° C. 1,000
Preferably, the pressure is up to 30,000 Pa.

Further, in a chromatogram of gel permeation chromatography (GPC) of a tetrahydrofuran-soluble component (THF-soluble component) extracted from the toner, a main peak is found in a molecular weight region of 3,000 to 30,000. And a molecular weight of 300,000 to 3,000
A form having at least a subpeak in the region of 0000 is preferred. Further, a GPC chromatogram of a tetrahydrofuran-soluble component (THF-soluble component) extracted from the toner has a main peak in a molecular weight region of 4,000 to 20,000 and a molecular weight of 300,000 to 1.0.
A form having at least a subpeak in the region of 00000 is preferred. Further, the carboxyl group or acid anhydride group of the binder resin is maleic acid, maleic acid half ester,
It is preferable that the resin be produced from an acid monomer selected from at least one or more maleic anhydrides.
Further, the binder resin is preferably a styrene copolymer. Further, the magnetic toner is preferably a magnetic toner having magnetic toner particles containing a magnetic substance as a colorant.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in more detail with reference to preferred embodiments of the present invention. The present inventors have solved the various problems in the related art, and as a result of intensive studies to develop a dry toner that meets the above-mentioned object, the binder resin of the dry toner has an acid group, which has an oxazoline group. A toner having a controlled storage elastic modulus G ′ at a specific temperature, thereby providing low-temperature fixability,
The present invention has been found that a dry toner having extremely excellent high-temperature offset resistance can be obtained. That is, in the dry toner of the present invention, the carboxyl group or the acid anhydride group of the binder resin reacts with the oxazoline group of the compound or resin having two or more oxazoline groups in the molecule, which is an essential component of the toner. By forming a crosslinked structure in the binder resin, the toner becomes harder and the high-temperature offset resistance can be improved.

Further, the viscoelastic properties of the dry toner of the present invention were measured at 75 ° C., 125 ° C. and 195 ° C.
It has been found that the toner fixing performance can be effectively improved by controlling the value of the storage elastic modulus G ′ of the toner at each temperature to fall within the respective optimum ranges. That is, if the value of the storage elastic modulus G ′ of the toner at each temperature is controlled so that G ′ ₇₅ is relatively large, G ′ ₁₂₅ is relatively small, and G ′ ₁₉₅ is relatively large, the toner The low-temperature fixability can be improved without impairing the blocking resistance, and the high-temperature offset resistance can be maintained.

That is, since the dry toner of the present invention has a high G ′ at 75 ° C., which is close to room temperature, the toner maintains elasticity even when left in a high-temperature environment, and does not impair blocking resistance. . Further, when the toner is heated by the fixing device, since the G ′ at 125 ° C. is low, the elasticity of the toner does not impair the fixability, and the viscosity of the toner quickly decreases even in a high-speed fixing system. , Good fixability is maintained. Further, in the dry toner of the present invention, 195 ° C.
Is controlled so as to increase G ′, the elasticity of the toner is maintained even when the temperature of the fixing device rises excessively, and as a result, good high-temperature offset resistance is exhibited.

Furthermore, in addition to having the viscoelastic properties at each temperature as described above, the dry toner of the present invention also contains, as described above, a binder resin having a crosslinked structure crosslinked with oxazoline. Since it is used, the developability of the toner can be further improved. That is, in the dry toner of the present invention, resin structure crosslinked by oxazoline is relatively hard, and, for G _'75 of the toner mentioned above is relatively large, the toner particles have a certain degree of hardness As a result, deterioration due to long-term use of the toner is reduced, and stable image density can be maintained for a long period of time.

Furthermore, in the dry toner of the present invention, as described above, the compound or resin component having an oxazoline group and the carboxyl group or acid anhydride group in the binder resin are crosslinked to form an amide bond. However, the toner having an amide bond has good wettability with a sheet to be fixed such as paper and has high affinity, and thus has an effect of improving the fixing property.
Thus, the dry toner of the present invention, since the high configure the value of G _'195, it is considered that low-temperature fixing property may become poor when applied to the fixing system at high speed, an amide bond described above Since it is contained in the toner, such low-temperature fixability does not deteriorate.

As described above, in the dry toner of the present invention, a crosslinked structure is formed in the binder resin, and the storage elastic modulus G 'of the toner at each temperature is controlled to a specific value. By doing so, the low-temperature fixability of the toner,
High temperature offset resistance and image stability are all improved.

Furthermore, the dry toner of the present invention has a molecular weight distribution of 3,000 as measured by a gel permeation chromatography (GPC) chromatogram of a tetrahydrofuran (THF) soluble component extracted from the toner.
It has a peak in the range of 0 to 30,000 and
It is preferable to adopt a configuration configured to have at least a sub-peak in a region of 0000 to 3,000,000. In other words, if a low molecular weight component having a peak in the molecular weight range of 3,000 to 30,000 is present in the constituent components of the toner, the toner has good low-temperature fixability. And a molecular weight of 3
If a high molecular weight component having a peak in the range of 00000 to 3,000,000 is present, the toner will exhibit good hot offset resistance.

The low molecular weight components described above have low melt viscosities, and therefore have a molecular weight of 300,000 to 3,000,000.
The high-molecular weight component having a peak in the region is easily phase-separated and difficult to mix uniformly. However, in the dry toner of the present invention, the hard component crosslinked by the oxazoline group has a certain share in the toner during toner production. As a result, the dispersibility of the binder resin constituting the toner particles with the colorant and other additives can be improved.

Further, in the dry toner of the present invention, the components crosslinked with oxazoline are hard and have a low melt viscosity, so that they do not easily mix with the low molecular weight resin. However, in a preferred embodiment of the dry toner of the present invention, Molecular weight 300,000
Since high molecular weight components having peaks in the region of ~ 3,000,000 exist, these high molecular weight components
Since the crosslinked ultra-high molecular weight component and low molecular weight component are easily mixed, all the components in the toner are uniformly mixed as a result, and the dispersibility of each component constituting the toner can be further improved. it can. As a result, it is possible to reduce a decrease in image density and a reduction in image fog due to poor dispersion of the toner raw materials. Further, the component cross-linked with oxazoline is relatively hard, and may damage the photoreceptor, and it is considered that the flaw may cause fusion of the toner on the photoreceptor. However, in the dry toner of the present invention, the cross-linking component is also uniformly dispersed in the toner component, and as a result, the cross-linking component does not exist unevenly on the toner surface and damages the photoreceptor. Nothing.

As described above, the dry toner of the present invention is configured so that the binder resin has a crosslinked structure and is controlled so as to have a specific elasticity at each temperature. And more preferably, GPC of a tetrahydrofuran (THF) soluble component extracted from a toner.
By configuring to have a specific molecular weight distribution in the molecular weight distribution measured in the chromatogram,
Even more effectively, low-temperature fixability, high-temperature offset resistance,
Image stability can be improved. As a result, it is possible to greatly improve the reliability of the electrophotographic apparatus.

Hereinafter, the storage elastic modulus that characterizes the dry toner of the present invention will be described. Dry toner of the present invention, when measured viscoelastic properties, within the storage modulus G _'75 is 300,000~30,000,000Pa at 75 ° C., more preferably, 1,000,000～10 ,
And the storage elastic modulus G ′ _{125 at} 125 ° C. is 1,000 to 100,000.
Pa, more preferably 3,000 to 30,00.
In the range of 0 Pa, and a storage modulus G _'195 at 195 ° C. in the range of 200～40,000Pa, more preferably lies in the range of 1,000～30,000Pa.

[0026] That is, the G _'75 is less than 300,000, and blocking resistance of the toner is deteriorated, and further, a decrease in image density of the long-term use becomes severe. on the other hand,
If G _'75 is more than 30,000,000, toner fusing tends to occur. Also, G _'125 of the toner 1,000P
If it is less than a, the low-temperature fixability of the toner is improved, but the viscosity of the toner when the toner passes through the fixing device becomes too low, so that the fixed image is wound around the fixing roller. On the other hand, when G _'125 is more than 100,000, no effect is obtained in the low-temperature fixability of the toner. Further, when less than G _'195 of the toner 200 can not be obtained sufficiently high temperature offset resistance. On the other hand, when G _'195 is more than 40,000,
Low-temperature fixability deteriorates.

In the present invention, the above-mentioned viscoelastic properties were measured by the following measuring methods. <Measurement of Viscoelastic Properties of Toner> The storage elastic modulus at each temperature was measured under the following conditions using a viscoelasticity measuring device (rheometer) RDA-II (manufactured by Rheometrics). Measurement jig: A parallel plate with a diameter of 7.9 mm was used. -Measurement sample: After heating and melting the toner or the binder resin, it was molded into a cylindrical shape having a diameter of about 8 mm and a height of 2 to 5 mm to obtain a measurement sample. Measurement frequency: 6.28 radians / second Measurement distortion setting: Initial value was set to 0.1%, and measurement was performed in the automatic measurement mode. -Elongation correction of sample: Adjusted in automatic measurement mode. Measurement temperature: The temperature was raised from 35 ° C to 200 ° C at a rate of 2 ° C per minute.

The dry toner of the present invention is an oxazoline compound in which the binder resin has a carboxyl group or an acid anhydride and has two or more oxazoline groups in the molecule, or two or more oxazoline compounds in the molecule. It is characterized by containing a resin component having an oxazoline group. The oxazoline-based compound, or two or more oxazoline groups contained in the resin component having an oxazoline group, undergo a ring-opening addition reaction with a carboxyl group or an acid anhydride group contained in the binder resin to form an amide group and crosslink. Form the structure. As described above, it is considered that this crosslinked structure improves the offset resistance of the toner.

As a method for crosslinking a binder resin having a carboxyl group or an acid anhydride group with a compound or a resin component having an oxazoline group, for example, 20 to 350
Under the temperature condition of ° C., if necessary, a method of stirring and mixing in the presence of a polymer substance, an organic solvent, or another catalyst, a binder resin having a carboxyl group or an acid anhydride group, and an oxazoline group. And a method in which the compound or the resin component is heated and melt-mixed using a heat kneader, and a method in which the material or the resin component is heat-melted and mixed together with other toner raw materials during the production of the toner using a heat kneader. In terms of obtaining the storage elastic modulus G ′ of the specific toner, which is a constituent requirement of the toner of the present invention, a method of heat-melting and mixing a binder resin and a compound or a resin component having an oxazoline group, and heat-melting and mixing during toner production The method is preferred. In particular, these methods are also preferable in terms of productivity of the toner and easy control of the crosslinking reaction.

Hereinafter, each material constituting the dry toner of the present invention will be described. First, an oxazoline-based compound having two or more oxazoline groups in the molecule will be described. As the oxazoline-based compound used in the present invention, those represented by the following general formula are preferably used.

Embedded image In the above formula, R represents an n-valent aliphatic, alicyclic or aromatic hydrocarbon residue, and R ₁ , R ₂ , R ₃ and R ₄ may be the same or different , Each represents hydrogen or a lower alkyl group, and n represents an integer of 2 to 4.

The hydrocarbon residue represented by R is, for example, a residue of a saturated aliphatic hydrocarbon having about 1 to 20 carbon atoms such as methane, ethane, propane, butane, pentane and hexane, or ethylene, propylene. , A residue of an unsaturated aliphatic hydrocarbon having about 1 to 20 carbon atoms such as butene and pentene, or a residue of an alicyclic hydrocarbon having about 4 to 30 carbon atoms such as cyclobutane, cyclopentane, cyclohexane and cyclohexene Or a residue of an aromatic hydrocarbon having about 6 to 30 carbon atoms such as benzene, toluene, xylene, and naphthalene. Examples of the lower alkyl group represented by R ₁ , R ₂ , R ₃ and R ₄ include alkyl groups having about 1 to 4 carbon atoms such as methyl, ethyl, propyl and butyl. n is an integer of 2 to 4, but 2 or 3 is common.

Further, as specific compounds represented by the above general formula, for example, the following compounds can be favorably used. 1,2-bis - (Δ ² - oxazolinyl -2) benzene 1,3-bis - (Δ ² - oxazolinyl -2) benzene 1,4-bis - (Δ ² - oxazolinyl -2) benzene 1,2-bis - (Δ ² - oxazolinyl -2) cyclohexane 1,3-bis - (Δ ² - oxazolinyl -2) cyclohexane 1,4-bis - (Δ ² - oxazolinyl -2) cyclohexane 1,1-bis - (Δ ² - oxazolinyl -2) methylene-bis - (Δ ² - oxazolinyl -2) ethylene 1,3-bis - (Δ ² - oxazolinyl -2) propane 1,4-bis - (Δ ² - oxazolinyl -2) butane 1,3-bis- (4,4,5,5-tetramethyl-Δ ² −
Oxazolinyl-2) cyclohexane 1,4-bis- (4,4-dimethyl-5,5-dipropyl-Δ ² -oxazolinyl-2) benzene 1,2,4-tris- (Δ ² -oxazolinyl-2) benzene 1 , 2,4,5-tetrakis - (Δ ² - oxazolinyl -2) benzene 1,2,4,5-tetrakis - (Δ ² - oxazolinyl -2) cyclohexane

In the dry toner of the present invention, when an oxazoline-based compound having two or more oxazoline groups in the molecule is used, 0.001 to 30 parts by weight with respect to 100 parts by weight of the binder resin. , And preferably in a proportion of 0.01 to 20 parts by weight. That is, when the amount is less than 0.001 part by weight, sufficient high-temperature offset resistance cannot be obtained, and the image density tends to decrease. On the other hand, when the content is more than 30 parts by weight, the toner becomes too hard and may damage the photoreceptor, which may cause toner fusion.

Next, the resin component having two or more oxazoline groups in the molecule used in the present invention will be described.
Examples of monomers having an oxazoline group that can be used to obtain such a resin component include, for example, 2-vinyl-2
-Oxazoline, 2-vinyl-4-methyl-2-oxazoline, 2-vinyl-5-methyl-2-oxazoline,
2-vinyl-4-ethyl-2-oxazoline, 2-vinyl-5-ethyl-2-oxazoline, 2-isopropenyl-2-oxazoline, 2-isopropenyl-4-methyl-2-oxazoline, 2-isopropenyl -5-methyl-2-oxazoline, 2-isopropenyl-4-ethyl-2-oxazoline, 2-isopropenyl-5-ethyl-2-oxazoline, 2-isopropenyl-4,5-
Examples thereof include oxazoline group-containing polymerizable monomers such as dimethyl-2-oxazoline, and one or more kinds selected from these can be used. These oxazoline group-containing monomers have a content of 1 to
It is used in an amount of 60 parts by weight, preferably 1 to 40 parts by weight.

The monomers copolymerizable with the above-mentioned monomers having an oxazoline group include, for example, styrene, o-methylstyrene, p-methylstyrene, pt
-Butyl styrene, 1,3-dimethylstyrene, α-methylstyrene, vinylnaphthalene, vinyl aromatic compounds such as vinylanthracene, acrylonitrile, vinyl cyanide compounds such as methacrylonitrile, acrylic acid,
Examples thereof include unsaturated carboxylic acids such as methacrylic acid, and esters thereof. These are not only one kind, but two
It can be used as a mixture of more than two species. The molecular weight of the resin component formed from these monomers is 3,000 to 300,000 by weight average molecular weight, preferably 50,000 to 300,000.
It should just be 00-250,000.

The resin component having an oxazoline group used in the present invention can be prepared by various known methods. For example, in the solution polymerization method, it can be obtained by copolymerizing a mixture of monomers in a solvent at 40 to 150 ° C. in the presence of an appropriate radical generator or chain transfer agent. In addition, it can also be produced by a generally known suspension polymerization method or emulsion polymerization method. When the dry toner of the present invention contains a resin component having two or more oxazoline groups in the molecule formed as described above, the amount of the resin component is 0 to 100 parts by weight of the binder resin. 0.1 to 50 parts by weight, preferably 0.05 to 30 parts by weight.
It is blended in the range of parts by weight. That is, if less than 0.01 parts by weight, sufficient hot offset resistance cannot be obtained,
In addition, the image density tends to decrease. On the other hand, when the amount is more than 50 parts by weight, the toner becomes too hard and may damage the photoreceptor, which may cause toner fusion.

Next, the resin component having two or more oxazoline groups in the molecule used in the present invention will be described.
Examples of monomers having an oxazoline group that can be used to obtain such a resin component include, for example, 2-vinyl-2
-Oxazoline, 2-vinyl-4-methyl-2-oxazoline, 2-vinyl-5-methyl-2-oxazoline,
2-vinyl-4-ethyl-2-oxazoline, 2-vinyl-5-ethyl-2-oxazoline, 2-isopropenyl-2-oxazoline, 2-isopropenyl-4-methyl-2-oxazoline, 2-isopropenyl -5-methyl-2-oxazoline, 2-isopropenyl-4-ethyl-2-oxazoline, 2-isopropenyl-5-ethyl-2-oxazoline, 2-isopropenyl-4,5-
Examples thereof include oxazoline group-containing polymerizable monomers such as dimethyl-2-oxazoline, and one or more kinds selected from these can be used. These oxazoline group-containing monomers have a content of 1 to
It is used in an amount of 60 parts by weight, preferably 1 to 40 parts by weight.

The monomers copolymerizable with the above-mentioned monomers having an oxazoline group include, for example, styrene, o-methylstyrene, p-methylstyrene, pt
-Butyl styrene, 1,3-dimethylstyrene, α-methylstyrene, vinylnaphthalene, vinyl aromatic compounds such as vinylanthracene, acrylonitrile, vinyl cyanide compounds such as methacrylonitrile, acrylic acid,
Examples thereof include unsaturated carboxylic acids such as methacrylic acid, and esters thereof. These are not only one kind, but two
It can be used as a mixture of more than two species. The molecular weight of the resin component formed from these monomers is 3,000 to 300,000 by weight average molecular weight, preferably 50,000 to 300,000.
It should just be 00-250,000.

The resin component having an oxazoline group used in the present invention can be prepared by various known methods. For example, in the solution polymerization method, it can be obtained by copolymerizing a mixture of monomers in a solvent at 40 to 150 ° C. in the presence of an appropriate radical generator or chain transfer agent. In addition, it can also be produced by a generally known suspension polymerization method or emulsion polymerization method. When the dry toner of the present invention contains a resin component having two or more oxazoline groups in the molecule formed as described above, the amount of the resin component is 0 to 100 parts by weight of the binder resin. 0.1 to 50 parts by weight, preferably 0.05 to 30 parts by weight.
It is blended in the range of parts by weight. That is, if less than 0.01 parts by weight, sufficient hot offset resistance cannot be obtained,
In addition, the image density tends to decrease. On the other hand, when the amount is more than 50 parts by weight, the toner becomes too hard and may damage the photoreceptor, which may cause toner fusion.

As described above, the dry toner of the present invention has a GPC chromatogram of a THF-soluble component,
Molecular weight 3,000-30,000, preferably 4,000
Having a main peak in the range of 0 to 20,000, and
It is preferable to have at least a subpeak in a molecular weight region of 300,000 to 3,000,000, preferably 300,000 to 1,000,000. When the main peak is less than 3,000, the blocking resistance of the toner deteriorates. On the other hand, when the main peak exceeds 30,000,
The low-temperature fixability of the toner deteriorates. In addition, molecular weight 300,0
If there is no subpeak in the range of 00 to 3,000,000, the ultrahigh molecular weight component generated by the crosslinking reaction of the binder resin and the relatively low molecular weight component in the binder resin are not sufficiently mixed. This causes poor dispersion in the toner, making it impossible to impart uniform charge to individual toner particles, thereby deteriorating the developability of the toner. As a method of obtaining a toner having the above-mentioned molecular weight distribution, there is a method of separately producing a low molecular weight component and a high molecular weight component of a binder resin, mixing them and using the mixture as a binder resin composition for a toner.

In the present invention, the molecular weight distribution of the chromatogram of the toner by GPC using THF (tetrahydrofuran) as a solvent was measured under the following conditions. That is, the column is stabilized in a heat chamber at 40 ° C., THF is passed through the column at this temperature at a flow rate of 1 ml per minute, and about 100 μl of a THF sample solution is injected and measured. In measuring the molecular weight of the sample, the molecular weight distribution of the sample was calculated from the relationship between the logarithmic value of a calibration curve prepared from several types of monodisperse polystyrene standard samples and the count number. As a standard polystyrene sample for preparing a calibration curve, for example, Tosoh Corporation or Showa Denko Corporation has a molecular weight of 1
It is appropriate to use a sample of about 0 ² to 10 ^{7 and} to use at least about 10 standard polystyrene samples. An RI (refractive index) detector is used as the detector.

As the column, it is preferable to combine a plurality of commercially available polystyrene gel columns.
Shodex GPC KF-801 manufactured by Showa Denko KK
802, 803, 804, 805, 806, 807, 8
00P combination or Tosoh TSKgel G
_{1000H (H XL), G2000H (} H XL), G3000H
(H _XL ), G4000H (H _XL ), G5000H (H _XL ), G
6000H (H _XL ), G7000H (H _XL ), TSKgua
rd column can be mentioned.

The measurement sample is prepared as follows. A sample (toner) to be measured is put in THF, left for several hours, shaken sufficiently, mixed well with THF (until the sample is no longer united), and left still for 12 hours or more. At this time, the time of being left in THF is set to be 24 hours or more. Thereafter, a sample processing filter (pore size 0.2 to 0.5 μm, for example,
-25-2 (available from Tosoh Corporation) can be used as a GPC sample. The sample concentration is adjusted so that the resin component is 0.5 to 5 mg / ml.

The method for producing the binder resin composition having a carboxyl group or an acid anhydride group used in the present invention includes the following. For example, a high-molecular-weight polymer and a low-molecular-weight polymer are separately synthesized by a solution polymerization method, then they are mixed in a solution state, and then a solvent is removed; a solvent-blending method is performed by melt kneading with an extruder or the like; A two-stage polymerization method in which a low-molecular-weight polymer obtained by a synthesis method is dissolved in a monomer for constituting a high-molecular-weight polymer, suspension polymerization is performed, and the resin is washed and dried to obtain a resin composition. Among these, it is preferable to use a solution blending method from the viewpoint that a molecular weight distribution of a GPC chromatogram of a desired toner is easily obtained.

Examples of the method for synthesizing the high molecular weight component of the resin composition include a solution polymerization method, an emulsion polymerization method and a suspension polymerization method. Among them, the emulsion polymerization method is a method in which a monomer (monomer) almost insoluble in water is dispersed as small particles in an aqueous phase with an emulsifier, and polymerization is carried out using a water-soluble polymerization initiator. In this method, the heat of reaction is easily adjusted, and the termination reaction rate is low because the phase in which the polymerization is performed (the oil phase composed of the polymer and the monomer) and the aqueous phase are different. With a high degree of polymerization and a high degree of polymerization. Further, since the polymerization process is relatively simple, and because the polymerization product is fine particles, it is easy to mix with a colorant, a charge control agent, and other additives in the production of a toner. There is an advantage as a method for producing a binder resin for toner. However, the resulting polymer tends to be impure due to the added emulsifier, and an operation such as salting out is required to remove the polymer, which is complicated.
In order to avoid this inconvenience, it is convenient to utilize the following suspension polymerization method.

In the suspension polymerization, 100 parts by weight or less of the monomer (preferably 1 part by weight) is added to 100 parts by weight of the aqueous solvent.
(0 to 90 parts by weight). As the dispersant, polyvinyl alcohol, partially saponified polyvinyl alcohol, and calcium phosphate are used.
It is used in the range of 0.05 to 1 part by weight with respect to 00 parts by weight. The polymerization temperature is suitably from 50 to 95 ° C., but should be appropriately selected depending on the polymerization initiator used and the target polymer.

In preparing a high molecular weight polymer component of a resin composition suitable for constituting the dry toner of the present invention,
At the time of polymerization, it is preferable to use a polyfunctional polymerization initiator as exemplified below alone or in combination with a monofunctional polymerization initiator. Examples of the polyfunctional polymerization initiator having a polyfunctional structure include 1,1-di-t-butylperoxy-
3,3,5-trimethylcyclohexane, 1,3-bis- (t-butylperoxyisopropyl) benzene,
2,5-dimethyl-2,5- (t-butylperoxy)
Hexane, 2,5-dimethyl-2,5-di- (t-butylperoxy) hexyne-3, tris- (t-butylperoxy) triazine, 1,1-di-t-butylperoxycyclohexane, , 2-Di-t-butylperoxybutane, 4,4-di-butylperoxyvaleric acid-n-butyl ester, di-t-butylperoxyhexahydroterephthalate, di-t-butylperoxyazelate , Di-t-butylperoxytrimethyl adipate, 2,2-bis- (4,4-di-t-butylperoxycyclohexyl) propane, 2,2-t-
A polyfunctional polymerization initiator having a functional group having a polymerization initiation function such as two or more peroxide groups in one molecule, such as butylperoxyoctane and various polymer oxides; and diallyl peroxydicarbonate, t-butyl peroxide In a molecule such as oxymaleic acid, t-butyl peroxyallyl carbonate, and t-butyl peroxyisopropyl fumarate, there are both a functional group having a polymerization initiation function such as a peroxide group and a polymerizable unsaturated group in one molecule. And polyfunctional polymerization initiators.

Of these, more preferred are 1,
1-di-tert-butylperoxy-3,3,5-trimethylcyclohexane, 1,1-di-tert-butylperoxycyclohexane, di-tert-butylperoxyhexahydroterephthalate, di-tert-butylperoxyazelate And 2,2-bis- (4,4-di-t-butylperoxycyclohexyl) propane, and t-butylperoxyallyl carbonate.

The polyfunctional polymerization initiator is used to satisfy various performances required as a binder resin for a toner.
It is preferable to use together with a monofunctional polymerization initiator. In particular,
It is preferable to use these polyfunctional polymerization initiators together with a polymerization initiator having a decomposition temperature lower than the decomposition temperature for obtaining a half-life of 10 hours.

Specific examples of the monofunctional polymerization initiator include, for example, benzoyl peroxide, 1,1-di (t
-Butylperoxy) -3,3,5-trimethylcyclohexane, n-butyl-4,4-di (t-butylperoxy) valerate, dicumyl peroxide, α, α′-
Organic peroxides such as bis (t-butylperoxydiisopropyl) benzene, t-butylperoxycumene and di-t-butyl peroxide; azo and diazo compounds such as azobisisobutyronitrile and diazoaminoazobenzene Can be These monofunctional polymerization initiators are:
The polyfunctional polymerization initiator may be added to the monomer at the same time as the above-mentioned polyfunctional polymerization initiator. It is preferable to add it after the half-life indicated by the acidic polymerization initiator has elapsed. The above polymerization initiator is preferably used in an amount of 0.05 to 2 parts by weight based on 100 parts by weight of the monomer from the viewpoint of efficiency.

On the other hand, as a method for synthesizing the low molecular weight component of the binder resin used in the present invention, a known method can be used. However, in the bulk polymerization method, a polymer having a low molecular weight can be obtained by polymerizing at a high temperature to increase the termination reaction rate, but there is a problem that the reaction is difficult to control. In this regard, in the solution polymerization method, a low-molecular-weight polymer can be easily obtained under mild conditions by utilizing the difference in radical chain transfer depending on the solvent and adjusting the amount of the polymerization initiator and the reaction temperature. Therefore, it is preferable as a method for obtaining a low molecular weight polymer of the resin composition used in the present invention. Among them, in order to highly control the acid component and molecular weight, for example,
A method of obtaining a low molecular weight polymer by mixing a plurality of polymers having different molecular weights and compositions, a method of post-adding monomers having different compositions, and the like can be used.

As a medium used in the solution polymerization, xylene, toluene, cumene, cellosolve acetate, isopropyl alcohol, benzene and the like can be used. In the case of a styrene monomer mixture, xylene, toluene or cumene is preferred. What is necessary is just to select and use suitably according to the polymer produced by polymerization.

The carboxyl group-containing monomer for introducing a carboxyl group or an acid anhydride group into the binder resin used in the present invention includes, for example, acrylic acid, methacrylic acid, α-ethylacrylic acid, crotonic acid and the like. Acrylic acid, and its α- or β-alkyl derivatives, fumaric acid, maleic acid, unsaturated dicarboxylic acids such as citraconic acid, and its half ester derivatives, maleic anhydride, and the like. A desired binder resin can be produced by copolymerizing with another monomer alone or in combination.

The unsaturated dicarboxylic acid half ester which can be used in the present invention includes, for example, monomethyl maleate, monoethyl maleate, monobutyl maleate, monooctyl maleate, monoallyl maleate,
Half esters of α, β-unsaturated dicarboxylic acids such as monophenyl maleate, monomethyl fumarate, monoethyl fumarate, monobutyl fumarate, monophenyl fumarate, etc., monobutyl n-butenylsuccinate, monomethyl n-octenyl succinate, Half-esters of alkenyldicarboxylic acids such as monoethyl n-butenylmalonate, monomethyl n-dodecenylglutarate, monobutyl n-butenyladipate, monomethyl phthalate, monoethyl phthalate, monobutyl phthalate, etc. And half esters of aromatic dicarboxylic acids. In the present invention, among these, maleic acid, maleic acid half ester, and maleic anhydride are particularly preferably used from the viewpoint of toner productivity.

Examples of the type of the binder resin used in the present invention include a homopolymer of styrene such as polystyrene, poly-p-chlorostyrene and polyvinyltoluene and a substituted product thereof; styrene-p-chlorostyrene copolymer. Styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-acrylate copolymer, styrene-methacrylate copolymer, styrene-α-chloromethyl methacrylate copolymer, styrene- Acrylonitrile copolymer, styrene-vinyl methyl ether copolymer, styrene-vinyl ethyl ether copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile- Styrene copolymers such as indene copolymers Coalescing; polyvinyl chloride, phenolic resin, natural modified phenolic resin, natural resin modified maleic acid resin, acrylic resin, methacrylic resin, polyvinyl acetate, silicone resin, polyester resin, polyurethane, polyamide resin, furan resin, epoxy resin, xylene resin , Polyvinyl butyral, terpene resin, coumarone indene resin, petroleum resin and the like can be used. Further, a crosslinked styrene resin is also a preferable binder resin. By introducing a carboxyl group or an acid anhydride group into these binder resins, a binder resin constituting the dry toner of the present invention can be obtained.

In the present invention, it is particularly preferable to use a styrene copolymer from the viewpoint of the development stability of the toner under high temperature and high humidity. Examples of comonomers for the styrene monomer of the styrene copolymer include acrylic acid, methyl acrylate, ethyl acrylate, butyl acrylate, dodecyl acrylate, octyl acrylate,
2-ethylhexyl acrylate, phenyl acrylate, methacrylic acid, methyl methacrylate, ethyl methacrylate, butyl methacrylate, octyl methacrylate,
Monocarboxylic acids having a double bond such as acrylonitrile, methacrylonitrile, acrylamide and the like or substituted products thereof; for example, maleic acid, butyl maleate,
Dicarboxylic acids having a double bond such as methyl maleate, dimethyl maleate and the like and substituted products thereof; for example, vinyl esters such as vinyl chloride, vinyl acetate, vinyl benzoate and the like, for example, ethylene, propylene, butylene and the like Vinyl monomers such as vinyl methyl ketone and vinyl hexyl ketone; vinyl ethers such as vinyl methyl ether, vinyl ethyl ether and vinyl isobutyl ether; Can be used alone or in combination.

As the binder resin constituting the dry toner of the present invention, a resin having a carboxyl group or an acid anhydride group is used, and the acid value of the binder resin is such that the crosslinking reaction is easy to control. It is preferably from 0.5 to 50 mgKOH / g, and more preferably from 1 to 30 mgKOH / g. In the present invention, the acid value of the binder resin was determined by the following method.

<Measurement of Acid Value> The basic operation is JIS K-0.
070 in accordance with the following procedures. About 0.5 to 2.0 (g) of the pulverized binder resin is precisely weighed, and the measured value is defined as the weight W (g) of the binder resin. The sample weighed above was placed in a 300 (ml) beaker, and a toluene / ethanol (4/1) mixed solution 15 was prepared.
Add 0 (ml) and dissolve. Using a 0.1N KOH methanol solution, titration is performed using a potentiometric titrator. At this time, for example, a potentiometric titrator AT-400 manufactured by Kyoto Electronics Co., Ltd. (win
workstation) and automatic titration using an ABP-410 motorized burette. The amount of the KOH solution obtained at this time is S (ml)
The blank is measured at the same time, and the amount of the KOH solution used at that time is defined as B (ml). Calculate the acid value by the following formula. f is a factor of KOH.

(Equation 1)

The dry toner of the present invention may contain the following waxes. Examples of the wax that can be used at this time include, for example, paraffin wax and its derivatives, montan wax and its derivatives,
Examples include microcrystalline wax and its derivatives, Fischer-Tropsch wax and its derivatives, polyolefin wax and its derivatives, carnauba wax and its derivatives, and the like. The above derivatives include oxides,
A block copolymer with a vinyl monomer and a graft-modified product are also included. The amount of wax contained in the toner is
It is effective to add 0.1 to 15 parts by weight, preferably 0.5 to 12 parts by weight, based on 100 parts by weight of the binder resin. A wax may be selected and used in combination.

Examples of the colorant that can be used in the toner of the present invention include the following pigments or dyes. As a colorant of the toner, for example, as a pigment, carbon black, aniline black, acetylene black,
Naphthol yellow, Banza yellow, Rhodamine lake, Alizarin lake, Bengala, Phthalocyanine blue, Indanthrene blue and the like can be used. These pigments may be used in an amount necessary and sufficient to maintain the optical density of the fixed image. For example, based on 100 parts by mass of the binder resin, 0.1 to 20 parts by mass, preferably 0.2 to 20 parts by mass.
It is preferable to add in the range of 10 parts by mass. For the same purpose, the following dyes can be used. For example, azo dyes, anthraquinone dyes, xanthene dyes, methine dyes, and the like can be used.
0.1 to 20 parts by weight, preferably 0.1 to 20 parts by weight, based on parts by weight.
It can be used in an amount of 3 to 10 parts by mass.

Further, the toner of the present invention may contain a magnetic material as a colorant to form a magnetic toner. However, in the present invention, from the viewpoints of charge stability and productivity of the toner,
It is preferable to use a magnetic material as a coloring agent. Examples of the magnetic material used in the present invention include iron oxides such as magnetite, hematite, and ferrite; metals such as iron, cobalt, and nickel; and aluminum, cobalt, copper, lead, magnesium, tin, zinc, antimony, and the like of these metals.
Examples of the magnetic material include alloys of metals such as beryllium, bismuth, cadmium, calcium, manganese, selenium, titanium, tungsten, and vanadium, and mixtures thereof.

For these magnetic materials, it is preferable to use particles having an average particle size of 2 μm or less, preferably about 0.1 to 0.5 μm. The amount to be contained in the toner is about 20 to 200 parts by mass, particularly preferably 40 to 1 part by mass, per 100 parts by mass of the resin component.
It may be used in a range of 50 parts by mass. In addition, these magnetic materials have a magnetic characteristic when 10K Oersted is applied.
The coercive force ratio (H _c) 20 to 300 oersted, a saturation magnetization (σ _s) 50~200emu / g, a residual magnetization (sigma _r). 2 to
Those having 20 emu / g are preferred.

The dry toner of the present invention may be configured to contain a charge control agent as described below. The following substances can be used to control the toner to be negatively charged. For example, an organic metal complex and a chelate compound are effective, and examples thereof include a monoazo metal complex, an acetylacetone metal complex, an aromatic hydroxycarboxylic acid, and an aromatic dicarboxylic acid-based metal complex. Other examples include aromatic hydroxycarboxylic acids, aromatic mono- and polycarboxylic acids and their metal salts, anhydrides, esters, and phenol derivatives such as bisphenol. Among these, a monoazo metal complex is particularly preferably used.

The following substances can be used for controlling the toner to be positively charged. For example, denatured products such as nigrosine and fatty acid metal salts, quaternary ammonium salts such as tributylbenzylammonium-1-hydroxy-4-naphthosulfonate, tetrabutylammonium tetrafluoroborate, and phosphonium salts which are analogs thereof Onium salts of these and their lake pigments, triphenylmethane dyes and these lake pigments (as the lacking agent, phosphotungstic acid, phosphomolybdic acid, phosphotungsten molybdic acid, tannic acid, lauric acid, gallic acid, ferricyanide) , Ferrocyanide, etc.) metal salts of higher fatty acids; diorganotin oxides such as dibutyltin oxide, dioctyltin oxide, dicyclohexyltin oxide; dibutyltin borate, dioctyltin borate, dicyclohexyl Diorgano tin borate such as Suzuboreto; can be used in combination singly, or two or more kinds.

When the dry toner of the present invention is used for image formation, it is preferable that an inorganic fine powder or a hydrophobic inorganic fine powder is externally added to the toner obtained above to form a developer. As the inorganic fine powder used at this time, for example, fine silica powder, fine titanium oxide powder, or a hydrophobized product thereof can be used. These are preferably used alone or in combination. Examples of the silica fine powder include both dry silica produced by vapor phase oxidation of a silicon halide compound or fumed silica, and wet silica produced from water glass and the like. It is preferable to use dry silica having few silanol groups inside and no production residue.

In the dry toner of the present invention, it is particularly preferable to use hydrophobic fine powder of silica as an external additive. In the hydrophobic treatment, hydrophobicity is imparted by chemically treating with an organosilicon compound which reacts or physically adsorbs with the fine silica powder. As a preferable method, a method of treating a dry silica fine powder produced by a vapor phase oxidation of a silicon halide compound with a silane coupling agent or treating with a silane coupling agent and simultaneously with an organosilicon compound such as silicone oil. Is mentioned.

Examples of the silane coupling agent used for the hydrophobizing treatment include hexamethyldisilazane, trimethylsilane, trimethylchlorosilane, trimethylethoxysilane, dimethyldichlorosilane, methyltrichlorosilane, allyldimethylchlorosilane, allyl Phenyldichlorosilane, benzyldimethylchlorosilane,
Bromomethyldimethylchlorosilane, α-chloroethyltrichlorosilane, β-chloroethyltrichlorosilane, chloromethyldimethylchlorosilane, triorganosilanemercaptan, trimethylsilylmercaptan,
Triorganosilyl acrylate, vinyldimethylacetoxysilane, dimethylethoxysilane, dimethyldimethoxysilane, diphenyldiethoxysilane, hexamethyldisiloxane, 1,3-divinyltetramethyldisiloxane, 1,3-diphenyltetramethyldisiloxane .

Examples of the organosilicon compound used for the hydrophobizing treatment include silicone oils. Preferred silicone oils have a viscosity of about 3 at 25 ° C.
Those having 0 to 1,000 centistokes are used.
For example, it is preferable to use dimethyl silicone oil, methylphenyl silicone oil, α-methylstyrene-modified silicone oil, chlorophenyl silicone oil, and fluorine-modified silicone oil.

As a method of hydrophobizing treatment with silicone oil, for example, silica fine powder treated with a silane coupling agent and silicone oil may be directly mixed using a mixer such as a Henschel mixer, or Alternatively, a method of injecting silicone oil into silica to be used may be used. Alternatively, after the silicone oil is dissolved or dispersed in an appropriate solvent, the mixture may be mixed with the base silica fine powder, and the hydrophobic treatment may be performed by removing the solvent.

In particular, as a preferred method of hydrophobizing silica fine powder, a method of treating with dimethyldichlorosilane, followed by treatment with hexamethyldisilazane, and further with silicone oil can be mentioned. As described above, those obtained by treating silica fine powder with two or more silane coupling agents and thereafter performing oil treatment can effectively increase the degree of hydrophobicity, and thus are preferably used in the dry toner of the present invention. Can be Further, in the present invention, the above-mentioned silica fine powder is subjected to a hydrophobic treatment with a silane coupling agent, or a hydrophobic treatment with a silicone oil to titanium oxide fine powder. Similarly, it can be preferably used.

Further, if necessary, an external additive other than silica fine powder or titanium oxide fine powder may be added to the dry toner of the present invention to form a developer. In this case, for example, resin fine particles or inorganic fine particles acting as a charge auxiliary agent, a conductivity-imparting agent, a fluidity-imparting agent, an anti-caking agent, a lubricant, an abrasive, etc. can be externally added.

The fine resin particles used in this case preferably have an average particle size of 0.03 to 1.0 μm.
Examples of the polymerizable monomer constituting the resin particles include styrene; o-methylstyrene, m-methylstyrene, and p-methylstyrene.
-Methylstyrene, p-methoxystyrene, p-ethylstyrene derivative; acrylic acid; methacrylic acid; methyl acrylate, ethyl acrylate, n-butyl acrylate;
Acrylates such as isobutyl acrylate, n-propyl acrylate, n-octyl acrylate, dodecyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, 2-chloroethyl acrylate, phenyl acrylate; methyl methacrylate, methacryl Ethyl acrylate, n-propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, phenyl methacrylate, dimethylaminoethyl methacrylate, methacryl Methacrylic esters such as diethylaminoethyl acrylate; and monomers such as acrylonitrile, methacrylonitrile, and acrylamide.

In the case of producing resin particles using the polymerizable monomers as described above, the polymerization method includes suspension polymerization,
Examples include emulsion polymerization and soap-free polymerization. More preferably, it is preferable to use resin particles obtained by soap-free polymerization. In particular, when the resin fine particles as described above are contained in the toner, as a primary charging device,
It has been confirmed that an image forming apparatus using a contact charging means such as a roller, a brush or a blade has a great effect in preventing the toner from fusing to the photosensitive drum.

Other fine particles include lubricants such as Teflon, zinc stearate and polyvinylidene fluoride (of which polyvinylidene fluoride is preferable); cerium oxide;
Polishing agents such as silicon carbide and strontium titanate (among which strontium titanate is preferred); fluidity-imparting agents such as titanium oxide and aluminum oxide (among which hydrophobics are particularly preferred); anti-caking agents; carbon black; Conductivity imparting agents such as zinc oxide, antimony oxide, and tin oxide are exemplified. Further, it is preferable to use a small amount of white fine particles and black fine particles having a polarity opposite to that of the toner as a developing property improver. The above-mentioned resin fine particles, inorganic fine powder, or hydrophobic inorganic fine powder externally added to the toner particles are used in an amount of 0.01 to 100 parts by weight of the toner.
It is preferable to use 5 parts by weight, preferably 0.05 to 3 parts by weight.

In preparing the dry toner of the present invention having the above-described structure, the following method can be used. For example, a binder, a colorant and a resin component having an oxazoline-based compound or an oxazoline group, and other additives are sufficiently mixed by a mixer such as a ball mill, and then heated rolls, a kneader, and a heat kneader such as an extruder. After melting, kneading and kneading, cooling and solidifying, pulverization and strict classification are performed to obtain toner particles having a desired particle size. Further, if necessary, the desired additive is sufficiently mixed with the toner particles obtained above by a mixer such as a Henschel mixer and externally added, whereby the dry process of the present invention having the specific structure described above is performed. A toner can be obtained.

[0076]

The present invention will be described more specifically below with reference to examples and comparative examples. All parts in the following formulations are parts by weight. << Oxazoline group-containing component >> (Production of oxazoline group-containing resin component A-1)
A 4-liter glass four-necked flask with a stirrer was equipped with a reflux condenser, a thermometer, a dropping funnel, and a nitrogen gas blowing tube, and charged with 1,250 parts of deionized water and 0.55 part of polyvinyl alcohol. The mixture was heated to 80 ° C. in a gas atmosphere to dissolve the polyvinyl alcohol, and then cooled to 50 ° C. Separately, 570 parts of styrene and 30 parts of 2-isopropenyl-2-oxazoline are mixed in a separate container,
2.6 parts of benzoyl peroxide was added to prepare a uniform polymerizable monomer solution (hereinafter simply referred to as a monomer solution). The monomer solution thus obtained was added to the flask, and the mixture was kept in a nitrogen gas atmosphere under stirring at 300 rpm for 10 minutes to bring the monomer solution into a suspended state.
The temperature was raised to 0 ° C. to start the polymerization, and then kept at this temperature for 7 hours to complete the polymerization. Next, the obtained reaction solution was added to 20
After filtering through a 0-mesh wire net, washing thoroughly with deionized water, and drying all day and night with a hot air circulating drier at 80 ° C., containing a particulate oxazoline group having a diameter of about 0.18 mm and a weight average molecular weight of 135,000. Resin component A-1 was obtained.

(Production of oxazoline group-containing resin component A-2) In the production of oxazoline group-containing resin component A-1, the monomer composition in the monomer solution was changed to styrene 450
Parts, 2-isopropenyl-2-oxazoline 50 parts and benzoyl peroxide 1.2 parts,
In the same manner as in Production Example 1, a particulate oxazoline group-containing resin component A-2 having a diameter of about 0.21 mm and a weight average molecular weight of 142,000 was obtained.

(Production of oxazoline group-containing resin component A-3) In the production of oxazoline group-containing resin component A-1, the monomer composition in the monomer solution was changed to styrene 495
Part, 2-isopropenyl-2-oxazoline 5 parts,
A granular resin component A-3 having a diameter of about 0.22 mm and a weight average molecular weight of 145,000 was obtained in the same manner as in Production 1 of A-1, except that 28 parts of benzoyl peroxide was used.

[Production Example of Resin] << Synthesis Example of High Molecular Weight Polymer >> (Synthesis of High Molecular Weight Polymer (H-1)) In a four-necked flask, 180 parts by weight of degassed water and 2% by weight of polyvinyl alcohol were added. After adding 20 parts by weight of the aqueous solution, 75 parts by weight of styrene, 20 parts by weight of n-butyl acrylate, 5 parts by weight of monobutyl maleate, and 2,2-bis (4,4-di-
A mixed solution of 0.10 parts by weight of a solution of tert-butylperoxycyclohexyl) propane (half-life of 10 hours, temperature of 92 ° C.) was added and stirred to form a suspension. After sufficiently replacing the inside of the flask with nitrogen, the temperature was raised to 85 ° C. to initiate polymerization. The temperature was maintained for 24 hours to complete the polymerization. This was separated by filtration, washed with water and dried to obtain a high molecular weight polymer (H-1). When the obtained high molecular weight polymer (H-1) was analyzed, the peak molecular weight was 800,000 and the acid value was 7.9.

(Synthesis of High Molecular Weight Polymer (H-2))
Except that the amount of 2-bis (4,4-di-tert-butylperoxycyclohexyl) propane was changed to 0.08 parts by weight, the same procedure as in the high-molecular-weight polymer (H-1) was carried out. -2) was obtained. The resulting high molecular weight polymer (H
Analysis of -2) revealed a peak molecular weight of 880,000 and an acid value of 8.0.

(Synthesis of High Molecular Weight Polymer (H-3))
Except that the amount of 2-bis (4,4-di-tert-butylperoxycyclohexyl) propane was changed to 0.25 parts by weight, a high-molecular-weight polymer (H) was prepared in the same manner as the high-molecular-weight polymer (H-1). -3) was obtained. The resulting high molecular weight polymer (H
Analysis of -3) revealed a peak molecular weight of 660,000 and an acid value of 7.8.

(Synthesis Example of Low-Molecular-Weight Polymer) (Synthesis of Low-Molecular-Weight Polymer (L-1)) 300 parts by weight of xylene was charged into a four-necked flask, and the inside of the vessel was sufficiently purged with nitrogen while stirring. Then, the temperature is raised to reflux. Under the reflux, a mixed solution of 83 parts by weight of styrene, 17 parts by weight of n-butyl acrylate, 0.1 part by weight of monobutyl maleate, and 1.7 parts by weight of di-tert-butyl peroxide was added for 4 hours. After the dropwise addition, the mixture was held for 2 hours to complete the polymerization to obtain a low molecular weight polymer (L-1) solution. A part of the obtained polymer solution was sampled, dried under reduced pressure, and analyzed for a low molecular weight polymer (L-1). As a result, the peak molecular weight was 16,200 and the acid value was 0.2. Was.

(Synthesis of Low Molecular Weight Polymer (L-2))
Polymerization was performed in the same manner as in the synthesis of the low molecular weight polymer (L-1) except that the amount of tert-butyl peroxide was changed to 2.5 parts by weight. Obtained. A part of this polymer solution was sampled, dried under reduced pressure, and the obtained low molecular weight polymer (L-2) was analyzed. The peak molecular weight was 8,100 and the acid value was 0.2. there were.

(Synthesis of Low Molecular Weight Polymer (L-3))
Polymerization was carried out in the same manner as in the synthesis of the low molecular weight polymer (L-1) except that the amount of tert-butyl peroxide was changed to 1.2 parts by weight, and the low molecular weight polymer (L-3) solution was obtained. Obtained. A part of this polymer solution was sampled, dried under reduced pressure, and the obtained low molecular weight polymer (L-3) was analyzed. As a result, the peak molecular weight was 21,400 and the acid value was 0.2. .

(Synthesis of Low Molecular Weight Polymer (L-4))
Polymerization is carried out in the same manner as in the synthesis of the low molecular weight polymer (L-1) except that the amount of tert-butyl peroxide is 5.0 parts by weight, to obtain a low molecular weight polymer (L-4) solution. Was. A part of this polymer solution was sampled, dried under reduced pressure, and the obtained low molecular weight polymer (L-4) was analyzed.
Met.

(Synthesis of Low Molecular Weight Polymer (L-5))
Polymerization was carried out in the same manner as in the synthesis of the low molecular weight polymer (L-1) except that the amount of tert-butyl peroxide was 0.3 parts by weight, and the low molecular weight polymer (L-5) solution was obtained. Obtained. A part of this polymer solution was sampled, dried under reduced pressure, and the obtained low molecular weight polymer (L-5) was analyzed. As a result, the peak molecular weight was 31,300 and the acid value was 0.2. .

Next, the high molecular weight polymers (H-1) to (H-3) and the low molecular weight polymer (L-
Using 1) to (L-5), each was blended at a ratio as shown in Table 1 to obtain a binder resin used in Examples and Comparative Examples by the following method. First, xylene 10
0 parts by weight, and charged so that the total of each high molecular weight polymer and low molecular weight polymer becomes 100 parts by weight. The mixture was heated, stirred under reflux, and kept for 12 hours. By leaving, a resin composition was obtained. Next, the obtained resin was cooled and solidified, and then pulverized to obtain a resin composition for toner (binder resins 1 to 8). GPC chromatograms and acid values were measured for the properties of the binder resins 1 to 8 thus obtained, and the results are shown in Table 1.

Further, using these binder resins 1 to 8, toners of Examples 1 to 12 and Comparative Examples 1 to 8 were obtained as follows. As magnetic iron oxide, the number average particle size is 0.2
μm magnetic iron oxide particles were used, and the monoazo iron complex used was represented by the following formula.

Embedded image

[0089]

[Table 1]

Example 1 100 parts by weight of binder resin 1 in Table 1 100 parts by weight of magnetic iron oxide 5 parts by weight of particulate oxazoline group-containing resin component (A-1) 2 parts by weight of monoazo iron complex 2 parts by weight polypropylene wax 4 parts by weight The mixture having the above composition is melt-kneaded with a biaxial extruder heated to 130 ° C., and the cooled kneaded material is coarsely pulverized with a hammer mill, and the coarsely pulverized material is finely pulverized with a jet mill. The obtained finely pulverized powder was classified by a fixed wall type air classifier to produce a classified powder. Furthermore, the ultrafine powder and the coarse powder were strictly classified and removed from the obtained classified powder at the same time using a multi-segment classification device utilizing the Coanda effect (an elbow jet classifier manufactured by Nippon Mining Co., Ltd.) to obtain a weight average particle size. (D4) A negatively chargeable magnetic toner of 5.9 μm in this example was obtained. Table 2 summarizes the GPC measurement results and the viscoelasticity measurement results for the obtained toner. Further, 1.5 parts by weight of hydrophobic silica fine powder was added to 100 parts by weight of the magnetic toner obtained above, and the mixture was externally added by mixing with a Henschel mixer to prepare a developer 1.

[0091] Example 2 - Table 1 in the binder resin 1 100 parts Magnetic iron oxide 100 parts by weight of 1,3-bis (delta ² - oxazolinyl -2) benzene 0.5 parts by weight monoazo iron complex 2 4 parts by weight of polypropylene wax 4 parts by weight of the above material was used to obtain a negatively chargeable magnetic toner having a weight average particle diameter (D4) of 5.9 μm in the same manner as in Example 1. Table 2 summarizes the GPC measurement results and the viscoelasticity measurement results for the obtained toner. Furthermore,
A developer 2 was prepared by adding 1.5 parts by weight of hydrophobic silica fine powder to 100 parts by weight of the magnetic toner obtained above and mixing with a Henschel mixer and externally adding the mixture.

Example 3 First, 100 parts by weight of the binder resin 1 in Table 1 and 1 part by weight of the particulate oxazoline group-containing resin component (A-1) were added to 13 parts by weight.
Melt and knead with a twin-screw extruder heated to 0 ° C,
The cooled kneaded material was roughly pulverized with a hammer mill to obtain a resin composition a, which was used as a toner raw material. -101 parts by weight of resin composition a-100 parts by weight of magnetic iron oxide-2 parts by weight of monoazo iron complex-4 parts by weight of polypropylene wax In the same manner as in Example 1, the weight average particle size of this example ( D4) A 5.9 μm negatively charged magnetic toner was obtained. Table 2 summarizes the GPC measurement results and the viscoelasticity measurement results for the obtained toner. Further, 1.5 parts by weight of hydrophobic silica fine powder was added to 100 parts by weight of the magnetic toner obtained above, and the mixture was externally added by mixing with a Henschel mixer to prepare a developer 3.

Example 4 First, 100 parts by weight of binder resin 1 and 1,3-bis (Δ
² -Oxazolinyl-2) 1 part by weight of benzene at 130 ° C
Was melt-kneaded with a heated twin-screw extruder, and the cooled kneaded product was roughly pulverized with a hammer mill to obtain a resin composition b, which was used as a toner raw material. -101 parts by weight of resin composition b-100 parts by weight of magnetic iron oxide-2 parts by weight of monoazo iron complex-4 parts by weight of polypropylene wax In the same manner as in Example 1, the weight average particle diameter of this example ( D4) A 5.9 μm negatively charged magnetic toner was obtained. Table 2 summarizes the GPC measurement results and the viscoelasticity measurement results for the obtained toner. Further, hydrophobic silica fine powder 1.
5 parts by weight were mixed with a Henschel mixer and externally added to prepare a developer 4.

[0094] Example 5 Binder Resin 1 100 parts Magnetic iron oxide 100 parts by weight of 1,3-bis (delta ² - oxazolinyl -2) benzene 0.1 parts by weight monoazo iron complex 2 parts by weight of polypropylene 4 parts by weight of wax Using the above materials, a negatively-charged magnetic toner having a weight average particle diameter (D4) of 5.9 μm in this example was obtained in the same manner as in Example 1. Table 2 summarizes the GPC measurement results and the viscoelasticity measurement results for the obtained toner. Further, 1.5 parts by weight of hydrophobic silica fine powder was added to 100 parts by weight of the magnetic toner obtained above, and the mixture was externally added by mixing with a Henschel mixer to prepare a developer 5.

Example 6 Binder Resin 100 parts by weight Magnetic iron oxide 100 parts by weight Granular oxazoline group-containing resin component (A-1) 5 parts by weight Monoazo iron complex 2 parts by weight Polypropylene wax 4 parts by weight Using the materials, in the same manner as in Example 1, a negatively-charged magnetic toner having a weight average particle diameter (D4) of 5.9 μm in this example was obtained. Table 2 summarizes the GPC measurement results and the viscoelasticity measurement results for the obtained toner. Further, 1.5 parts by weight of hydrophobic silica fine powder was added to 100 parts by weight of the magnetic toner obtained above, and the mixture was externally added by mixing with a Henschel mixer to prepare a developer 6.

Example 7 Binder Resin 100 parts by weight Magnetic iron oxide 100 parts by weight Granular oxazoline group-containing resin component (A-1) 5 parts by weight Monoazo iron complex 2 parts by weight Polypropylene wax 4 parts by weight Using the materials, in the same manner as in Example 1, a negatively-charged magnetic toner having a weight average particle diameter (D4) of 5.9 μm in this example was obtained. Table 2 summarizes the GPC measurement results and the viscoelasticity measurement results for the obtained toner. Further, 1.5 parts by weight of hydrophobic silica fine powder was added to 100 parts by weight of the magnetic toner obtained above, and the mixture was externally added by mixing with a Henschel mixer to prepare a developer 7.

Example 8 100 parts by weight of binder resin 4 100 parts by weight of magnetic iron oxide 5 parts by weight of particulate oxazoline group-containing resin component (A-1) 2 parts by weight of monoazo iron complex 4 parts by weight of polypropylene wax Using the materials, in the same manner as in Example 1, a negatively-charged magnetic toner having a weight average particle diameter (D4) of 5.9 μm in this example was obtained. Table 2 summarizes the GPC measurement results and the viscoelasticity measurement results for the obtained toner. Further, 1.5 parts by weight of hydrophobic silica fine powder was added to 100 parts by weight of the magnetic toner obtained above, and the mixture was externally added by mixing with a Henschel mixer to prepare a developer 8.

Example 9 100 parts by weight of binder resin 5 100 parts by weight of magnetic iron oxide 5 parts by weight of particulate oxazoline group-containing resin component (A-1) 2 parts by weight of monoazo iron complex 4 parts by weight of polypropylene wax Using the materials, in the same manner as in Example 1, a negatively-charged magnetic toner having a weight average particle diameter (D4) of 5.9 μm in this example was obtained. Table 2 summarizes the GPC measurement results and the viscoelasticity measurement results for the obtained toner. Further, 1.5 parts by weight of hydrophobic silica fine powder was added to 100 parts by weight of the magnetic toner obtained above, and the mixture was externally added by mixing with a Henschel mixer to prepare a developer 9.

[0099] Example 10 Binder resin 1 100 parts Magnetic iron oxide 100 parts by weight of 1,3-bis (delta ² - oxazolinyl -2) cyclohexane 1 part by weight monoazo iron complex 2 parts Polypropylene wax 4 In the same manner as in Example 1, a negatively chargeable magnetic toner having a weight average particle size (D4) of 5.9 μm was obtained using the above materials. Table 2 summarizes the GPC measurement results and the viscoelasticity measurement results for the obtained toner. Further, 1.5 parts by weight of hydrophobic silica fine powder was added to 100 parts by weight of the magnetic toner obtained above, and the mixture was externally added by mixing with a Henschel mixer to prepare a developer 10.

Example 11 Binder Resin 100 parts by weight Magnetic iron oxide 100 parts by weight Granular oxazoline group-containing resin component (A-2) 10 parts by weight Monoazo iron complex 2 parts by weight Polypropylene wax 4 parts by weight Using the materials, in the same manner as in Example 1, a negatively-charged magnetic toner having a weight average particle diameter (D4) of 5.9 μm in this example was obtained. Table 2 summarizes the GPC measurement results and the viscoelasticity measurement results for the obtained toner. Further, 1.5 parts by weight of hydrophobic silica fine powder was added to 100 parts by weight of the magnetic toner obtained above, and the mixture was externally added by mixing with a Henschel mixer to prepare a developer 11.

Example 12 100 parts by weight of binder resin 1 100 parts by weight of magnetic iron oxide 1 part by weight of particulate oxazoline group-containing resin component (A-3) 2 parts by weight of monoazo iron complex 2 parts by weight of polypropylene wax 4 parts by weight Using the materials, in the same manner as in Example 1, a negatively-charged magnetic toner having a weight average particle diameter (D4) of 5.9 μm in this example was obtained. Table 2 summarizes the GPC measurement results and the viscoelasticity measurement results for the obtained toner. Further, 1.5 parts by weight of hydrophobic silica fine powder was added to 100 parts by weight of the magnetic toner obtained above, and the mixture was mixed with a Henschel mixer and externally added to prepare a developer 12.

[0102] Comparative Example 1 Binder resin 1 100 parts Magnetic iron oxide 100 parts by weight of 1,3-bis (delta ² - oxazolinyl -2) benzene 35 parts by weight monoazo iron complex 2 parts Polypropylene wax 4 In the same manner as in Example 1, a negatively chargeable magnetic toner having a weight average particle size (D4) of 5.9 μm was obtained using the above materials. Table 2 summarizes the GPC measurement results and the viscoelasticity measurement results for the obtained toner. Further, 1.5 parts by weight of hydrophobic silica fine powder was added to 100 parts by weight of the magnetic toner obtained above, and the mixture was externally added by mixing with a Henschel mixer to prepare a developer 13.

Comparative Example 2 Binder Resin 100 parts by weight Magnetic iron oxide 100 parts by weight Granular oxazoline group-containing resin component (A-1) 60 parts by weight Monoazo iron complex 2 parts by weight Polypropylene wax 4 parts by weight Using the materials, in the same manner as in Example 1, a negatively-charged magnetic toner having a weight average particle size (D4) of 5.9 μm in this comparative example was obtained. Table 2 summarizes the GPC measurement results and the viscoelasticity measurement results for the obtained toner. Further, 1.5 parts by weight of hydrophobic silica fine powder was added to 100 parts by weight of the magnetic toner obtained above, and the mixture was externally added by mixing with a Henschel mixer to prepare a developer 14.

Comparative Example 3 100 parts by weight of binder resin 6 100 parts by weight of magnetic iron oxide 2 parts by weight of monoazo iron complex 4 parts by weight of polypropylene wax This comparative example was made in the same manner as in Example 1 using the above materials. (D4) 5.9 μm was obtained. Table 2 summarizes the GPC measurement results and the viscoelasticity measurement results for the obtained toner. Further, 1.5 parts by weight of hydrophobic silica fine powder was added to 100 parts by weight of the magnetic toner obtained above, and the mixture was externally added by mixing with a Henschel mixer to prepare a developer 15.

[0105]Comparative Example 4  -Binder resin 7 100 parts by weight-Magnetic iron oxide 100 parts by weight-Granular oxazoline group-containing resin component (A-1) 5 parts by weight-Monoazo iron complex 2 parts by weight-Polypropylene wax 4 parts by weight In the same manner as in Example 1,
A negatively charged magnetic toner having an amount average particle size (D4) of 5.9 μm
Obtained. Table 2 shows the results of GPC measurement of the obtained toner.
And the results of the viscoelasticity measurement are shown together. Furthermore, on
100 parts by weight of the magnetic toner obtained in
Rica fine powder is added at a ratio of 1.5 parts by weight.
The mixture was mixed with a mixer and externally added to prepare a developer 16.

Comparative Example 5 100 parts by weight of binder resin 100 parts by weight of magnetic iron oxide 0.005 parts by weight of particulate oxazoline group-containing resin component (A-1) 2 parts by weight of monoazo iron complex 2 parts by weight of polypropylene wax 4 parts by weight Part In the same manner as in Example 1 using the above materials, a negatively-charged magnetic toner having a weight average particle size (D4) of 5.9 μm in this comparative example was obtained. Table 2 summarizes the GPC measurement results and the viscoelasticity measurement results for the obtained toner. Further, 1.5 parts by weight of hydrophobic silica fine powder was added to 100 parts by weight of the magnetic toner obtained above, and the mixture was externally added by mixing with a Henschel mixer to prepare a developer 17.

Comparative Example 6 Binder Resin 100 parts by weight Magnetic iron oxide 100 parts by weight Monoazochrome complex 5 parts by weight Monoazo iron complex 2 parts by weight Polypropylene wax 4 parts by weight Similarly, a negatively-charged magnetic toner having a weight average particle diameter (D4) of 5.9 μm in this comparative example was obtained. Table 2 summarizes the GPC measurement results and the viscoelasticity measurement results for the obtained toner. Further, 1.5 parts by weight of hydrophobic silica fine powder was added to 100 parts by weight of the magnetic toner obtained above, and the mixture was externally added by mixing with a Henschel mixer to prepare a developer 18.

Comparative Example 7 100 parts by weight of polyester resin (peak molecular weight 5000, no sub-peak, acid value 30 mg KOH / g) 100 parts by weight of magnetic iron oxide 5 parts by weight of particulate oxazoline group-containing resin component (A-1) Monomono Iron complex 2 parts by weight ・ Polypropylene wax 4 parts by weight Using the above materials, a negatively-charged magnetic toner having a weight average particle size (D4) of 5.9 μm of this comparative example was obtained in the same manner as in Example 1. Table 2 summarizes the GPC measurement results and the viscoelasticity measurement results for the obtained toner. Further, 1.5 parts by weight of hydrophobic silica fine powder was added to 100 parts by weight of the magnetic toner obtained above, and the mixture was externally added by mixing with a Henschel mixer to prepare a developer 19.

Comparative Example 8 100 parts by weight of binder resin 8 100 parts by weight of magnetic iron oxide 5 parts by weight of particulate oxazoline group-containing resin component (A-1) 2 parts by weight of monoazo iron complex 2 parts by weight of polypropylene wax Using the materials, in the same manner as in Example 1, a negatively-charged magnetic toner having a weight average particle size (D4) of 5.9 μm in this comparative example was obtained. Table 2 summarizes the GPC measurement results and the viscoelasticity measurement results for the obtained toner. Further, 1.5 parts by weight of hydrophobic silica fine powder was added to 100 parts by weight of the magnetic toner obtained above, and the mixture was externally added by mixing with a Henschel mixer to prepare a developer 20.

[0110]

[Table 2]

[0111]

[Evaluation] Next, the developing agents 1 to 20 prepared as described above using the toners of Examples and Comparative Examples were evaluated by the following methods. <Image output test> The dry toner was placed in a process cartridge, and a Canon laser beam printer LBP-
930 was remodeled by A4 transverse feed from 24 sheets / min to 32 sheets / min. Further, the total pressure between the heating roller and the pressure roller of the fixing device was set to 25 kg, and the nip was set to 7 mm. The process speed was set to 145 mm / sec. Under the above setting conditions, under high temperature and high humidity environment (32.5 ° C, 85% RH)
An image output test was performed under low temperature and low humidity (15 ° C., 10% RH), and the obtained images were evaluated for the following items. The print mode was 2 sheets / 20 sec.

(1) Image density, toner fusing, roller wrapping One sheet of ordinary paper for copying machines (75 g / m ² )
After printing out 2,000 sheets, measuring the image density at the start and end of image output, and observing the photoreceptor and the obtained image after outputting 12,000 sheets, exposure was performed from the solid black image. The evaluation of the fusion of the toner to the body was performed. Image output environment is high temperature and high humidity environment (32.5 ° C, 85% RH)
The print mode was set to 2 sheets / 20 sec. or,
The winding around the fixing roller was also evaluated.

Image density The image density was measured using a Macbeth reflection densitometer (manufactured by Macbeth).
Was used to measure the relative density of a white background portion with a document density of 0.00 with respect to the printout image. Table 3 shows the results.

Fusion of toner to photoreceptor Toner fusion to the photoreceptor was evaluated by observing the photoreceptor and the obtained image by visual observation after 12,000 sheets of image were formed. Table 3 shows the results. A: No toner fusion was observed on the photoreceptor. ：: The toner was slightly fused on the photoreceptor, but did not appear on the image. Δ: Image omission of a white dot is observed on a solid black image. ×: Shooting star-shaped image omission is observed from a white point on a solid black image.

Winding around the fixing roller Further, a solid black image having a tip margin of 4.5 mm was imaged, and the winding around the fixing roller was evaluated according to the following criteria. Table 3 shows the results. A: No winding occurs. X: Winding occurs.

(2) Fog A fog was calculated from a comparison between the whiteness of the transfer paper measured by a reflectometer (manufactured by Tokyo Denshoku Co., Ltd.) and the whiteness of the transfer paper after printing solid white. The results are shown in FIG. The image output environment is a low temperature and low humidity environment (15 ° C, 10% R
H), and the print mode was 2 sheets / 20 sec.

<Low-temperature fixability, high-temperature offset resistance> The developer obtained by using the dry toners of the examples and comparative examples is placed in a process cartridge, and a Canon laser beam printer LBP-930 is fed by A4 transverse feed for 24 sheets. / Min. To 32 sheets / min., And the above-mentioned image output except that the surface temperature of the heating roller of the heating / pressing roller fixing device is modified from 120 ° C to 250 ° C. Set the same conditions as the tester and set the temperature to 5
° C, while changing the temperature in increments of
(0% RH), the image sample was printed out, and the following items were evaluated.

(1) Low-temperature fixability A fixed image was rubbed with a soft thin paper under a load of 50 g / cm ² , and the reduction rate (%) of the image density before and after rubbing was 1%.
The lowest temperature that is 0% or less is determined as the lowest fixing temperature,
The low-temperature fixability was evaluated, and the results are shown in Table 3. At this time, plain paper for copying machines (9
0 g / m ² ).

(2) High-temperature offset resistance A sample image having an image area ratio of about 5% is printed out.
High-temperature offset resistance was evaluated based on the degree of dirt that appeared on the image, and Table 3 shows the results. The values shown in Table 3 are the maximum temperatures at which no smear occurs on the image. At this time, plain paper for a copying machine (60 g / m ² ) in which an offset easily occurs was used as a test paper.

<Blocking Resistance Test> About 10 g of the toner was placed in a 100 cc polycop, left at 50 ° C. for 3 days, and the toner required in the polycop was visually observed and evaluated according to the following criteria. Table 3 shows the results. ◎: No aggregate was observed. ：: Aggregates are observed, but easily collapse. Δ: Aggregates are seen, but collapse when shaken ×: Aggregates can be grasped and do not collapse easily.

[0121]

[Table 3]

[0122]

As described above, according to the present invention,
Highly satisfying low-temperature fixing property, high-temperature offset resistance, and maintain high developability even under severe environmental conditions such as high temperature and high humidity, excellent blocking resistance, toner fusion to photoreceptor, A dry toner that does not cause roller wrapping can be provided.

[Brief description of the drawings]

FIG. 1 is a view showing a measurement result of a storage elastic modulus (G ′) of a toner of Example 1.

FIG. 2 is a diagram illustrating a GPC measurement result of the toner of Example 1.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Katsuhisa Yamazaki, Inventor, 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Koichi Toyama 3-30-2, Shimomaruko, Ota-ku, Tokyo No. F term in Canon Inc. (reference) 2H005 AA02 AA06 CA02 CA03 CA30 EA03 EA06 EA07 EA10

Claims (8)

[Claims] 1. A dry toner having toner particles containing at least a binder resin, a colorant and an oxazoline-based compound or a resin component having an oxazoline group, wherein the binder resin has a carboxyl group or an acid anhydride group. The resin contains 0.001 to 30 parts by weight of an oxazoline-based compound having two or more oxazoline groups in a molecule with respect to 100 parts by weight of the binder resin, or two in the molecule. The above resin component having an oxazoline group is contained in an amount of 0.01 to 50 parts by weight, and when its viscoelastic properties are measured, the storage elastic modulus at 75 ° C. G ′ ₇₅ is 300,000 to 30, , 000,000 Pa
And the storage elastic modulus G ′ _{125 at} 125 ° C. is 1,000
A dry toner having a storage modulus G ′ _{195 at 0} to 100,000 Pa and a storage elastic modulus at 195 ° C. of 200 to 40,000 Pa. 2. An oxazoline-based compound is contained in an amount of 0.01 to 20 parts by weight or a resin component having an oxazoline group in an amount of 0.05 to 20 parts by weight based on 100 parts by weight of a binder resin.
The dry toner according to claim 1, wherein the dry toner is contained in an amount of 30 to 30 parts by weight. 3. The storage elastic modulus G ′ _{75 at} 75 ° C. is 1,
1,000,000 to 10,000,000 Pa, and 1
Storage elastic modulus G ' _{125 at} 25 ° C is 3,000-30,
Is 000Pa, and, according to claim 1 the storage modulus G _'195 at 195 ° C. is 1,000~30,000Pa
Or the dry toner according to claim 2. 4. A gel permeation chromatography (GPC) chromatogram of a tetrahydrofuran (THF) -soluble component extracted from a toner has a main peak in a molecular weight region of 3,000 to 30,000, and Molecular weight 300,000-3,000,000
The dry toner according to any one of claims 1 to 3, wherein the dry toner has at least a sub-peak in a region (1). 5. A GPC chromatogram of a tetrahydrofuran (THF) soluble component extracted from a toner, which has a main peak in a molecular weight region of 4,000 to 20,000 and a molecular weight of 300,000 to 1,000.
The dry toner according to any one of claims 1 to 4, wherein the dry toner has at least a subpeak in a region of 0000. 6. The carboxyl group or the acid anhydride group of the binder resin is formed from an acid monomer selected from at least one of maleic acid, maleic acid half ester and maleic anhydride. The dry toner according to any one of claims 1 to 5. 7. The dry toner according to claim 1, wherein the binder resin is a styrene copolymer. 8. The dry toner according to claim 1, wherein the toner particles are magnetic toner particles containing a magnetic substance as a colorant.