JP5984528B2 - toner - Google Patents

Description

  The present invention relates to an electrophotographic method, an image forming method for developing an electrostatic image, and a toner used in a toner jet.

  In general electrophotography, a latent image is formed on an image carrier (photoreceptor), toner is supplied to the latent image to make a visible image, and the toner image is transferred to a transfer material such as paper. A method is known in which a toner image is fixed on a transfer material by heat / pressure to obtain a copy.

  In order to reduce the power consumption and shorten the wait time of an electrophotographic apparatus, an on-demand fixing apparatus combining a ceramic heater with a small heat capacity and a film has been put into practical use as a fixing apparatus.

In addition, with the recent increase in printing speed, the time for media such as toner and paper to pass through the nip of the fixing device has become shorter year by year.
Furthermore, in recent years, image data such as image data and posters captured by digital cameras, portable terminals, etc., and high-quality images such as graphic images with a high printing ratio, a user uses an image forming apparatus such as a laser printer (LBP). Opportunities to output using are increasing.

  Against this background, there has been a demand for a toner that exhibits excellent low-temperature fixability even under more severe fixing conditions, such as using images with a high print ratio in a short time and using thick paper.

  In order to achieve low-temperature fixing of the toner with such a fixing device, the toner needs to exhibit low-temperature fixability higher than that of the conventional toner. On the other hand, not only the non-crystalline polyester resin as the binder resin. There have been many proposals of toners using crystalline polyester resins.

It is known that the crystalline polyester resin can be improved in low-temperature fixability by being melted rapidly in the vicinity of the melting point to be compatible with the amorphous polyester resin and softening the entire binder resin.
In the case where a crystalline polyester resin is contained in the toner, proposals have been made to finely disperse the crystalline polyester resin in the toner (for example, Patent Document 1 and Patent Document 2). This is a technique for promoting the compatibilization of both resins by increasing the contact area between the amorphous polyester resin and the crystalline polyester resin.

  The toner in which the crystalline polyester resin is finely dispersed gradually melts from the outermost surface of the toner particles when heat is applied during fixing. Even with such toner, when fixing using media that is difficult to transmit heat, such as thick paper, the heat of the fixing roller on the paper side is difficult to transfer to the toner, so only the surface of the toner particles melts. The toner was not sufficiently fixed on the medium. As a solution, a method of applying a heat sufficient for fixing to the toner by slowing the printing speed and extending the passing time of the toner and the medium in the fixing nip is adopted. However, there is a problem in that productivity is reduced due to a long time required to print one sheet of paper.

  In general, a toner containing a crystalline polyester resin leaks the charge through the crystalline polyester resin even when the charge is held, so that the amount of charge on the toner particles is lowered depending on the standing time. As a result, there is a problem that the image is disturbed. As a measure against this, there is a step of idling the developing device to recharge the toner before reprinting. However, there is a problem that the time until the first printing becomes long.

  Conventionally, many annealing processes have been performed in order to control the dispersion state of the crystalline polyester resin in the toner. However, in the generally known annealing, the crystalline polyester resin has only a small aspect ratio due to surface tension, and has not yet solved the problem of charge leakage.

JP 2008-116613 A Japanese Patent No. 2011-145587

An object of the present invention is to provide a toner that solves the above problems.
The object of the present invention is to have an excellent low-temperature fixability without changing the fixing temperature even in fixing using a medium such as cardboard, which is difficult to transmit heat, and without lowering the printing speed. It is to provide a toner that is difficult to leak.

The present invention relates to a toner containing polyester resin A, polyester resin B, and a colorant.
(1) The polyester resin A is a resin having a portion capable of taking a crystal structure,
(2) The polyester resin B is a resin that does not have a portion capable of taking a crystal structure,
(3) In the transmission electron microscope (TEM) cross-section observation of the toner with, the cross-section of the toner has a domain from the polyester resin A, the major diameter of the largest domain diameter in the domain Is 3.0 μm or more,
(4) The average aspect ratio (major axis / minor axis) of the domain is 4.0 or more and 20.0 or less,
(5) A toner is provided in which the melting point Ta of the polyester resin A and the softening point Tb of the polyester resin B satisfy the following formula 1.
Ta <Tb Formula 1

  According to the present invention, the toner in which the maximum major axis and aspect ratio of the domain derived from the polyester resin A in the toner cross-section observation are controlled within a certain range and the softening point of the polyester resin B is higher than the melting point of the polyester resin A. By using the toner, it is possible to obtain a toner having good fixability and capable of preventing a decrease in charge amount due to standing.

FIG. 3 is a schematic view showing a cross section of one toner particle of the present invention.

  In the toner containing the polyester resin A having a portion capable of taking a crystal structure as the binder resin and the polyester resin B not having a portion capable of taking a crystal structure, the present inventors have determined the shape of the crystal structure in the toner. And the dispersion state.

  As a result, the present inventors, when observing the cross section of the toner particles, are excellent in fixability when using a thick paper, and the toner is charged only when the domain made of polyester resin A has a specific shape. It has been found that it exhibits an effect of excellent charging stability that is difficult to decrease. FIG. 1 is a schematic view showing the relationship between the polyester resin A and the polyester resin B in the cross section of one toner particle of the present invention. As shown in FIG. 1, the toner 1 particle of the present invention has a cross section in which the domain 10 derived from the polyester resin A is dispersed in the polyester resin B11. As shown by 10 in FIG. 1, the maximum long diameter of the domain consisting of the polyester resin A to be dispersed is increased, the domain consisting of the polyester resin A is made in a sharp shape from the toner surface toward the inside, and the polyester resin B is softened. It was found that by lowering the melting point of the polyester resin A than the point, the toner of the present invention is excellent in fixability when using thick paper and exhibits an effect that the charge amount is not easily lowered even when left.

  The toner of the present invention is characterized in that the maximum major axis of the domain made of polyester resin A is large, and has a sharp shape from the toner surface toward the inside, so that heat of the fixing roller is easily transmitted to the inside of the toner during fixing. It is. Further, the domain consisting of the polyester resin A is dispersed in the above-described state, whereby the charging stability at the time of charging is increased.

Details of the present invention will be described below.
The toner of the present invention has polyester resin A and polyester resin B as binder resins, and polyester resin A is a resin having a portion that can take a crystal structure, and polyester resin B has a portion that can take a crystal structure. It is a resin that does not. The polyester resin A exhibits a plasticizing effect on the polyester resin B only when heated at a temperature equal to or higher than the melting point as in fixing, and improves fixability.

  The reason why the toner of the present invention is excellent in fixability when using a medium that is difficult to transmit heat such as cardboard and is excellent in charging stability in which the amount of charge is not easily lowered by being left is not clear, but is presumed as follows. .

  When fixing using thick paper, compared to fixing plain paper, most of the amount of heat given from the fixing roller is absorbed by the paper medium, so there is enough heat to melt the toner. Does not reach the inside of the toner. Therefore, the design is such that the conveyance speed of the paper is decreased, the time for the paper to pass through the fixing roller is lengthened, and the toner is given a sufficient amount of heat to melt the toner.

  The conventional toner in which the crystalline polyester is finely dispersed, when heat is applied during fixing, the plasticity gradually proceeds from the toner surface toward the inside of the toner and is fixed.

  In the toner of the present invention, since the domain of the polyester resin A exists in a wedge-like state from the toner surface toward the inside of the toner, when heat is applied during fixing, the heat of the toner surface is converted to the crystal of the polyester resin A. It is transmitted to the inside of the toner instantly through the part. Therefore, since the plasticity progresses not only from the toner surface but also from the inside of the toner, it is assumed that fixing can be performed without reducing the fixing speed.

  In a conventional toner in which crystalline polyester is finely dispersed, if the charge is retained by friction and then left for a certain period of time, charge leakage occurs and the amount of charge decreases. This is because crystalline polyester is a substance that easily leaks charges.

  The toner of the present invention has a high aspect ratio of the polyester resin A domain. In other words, the crystalline polyester is dispersed in an elongated state in the toner. In general, the crystalline polyester and the amorphous polyester have different volume resistance values, and the crystalline polyester is easy to pass charges. In the toner of the present invention, it is surmised that the crystalline part of the polyester resin A serves as an electrode for conducting electricity, and the polyester resin B serves as an insulating layer. Therefore, a plurality of minute capacitors exist in the toner. It is inferred that the Therefore, it is presumed that the toner easily retains the electric charge given by frictional charging and is excellent in charging stability. In the present invention, since the ability to hold electric charge is important, the capacitor capacity, which is a general capacitor, is important. It is known that the capacitor capacity is proportional to the area of the electrode and inversely proportional to the distance between the electrodes. In the toner of the present invention, the domain composed of the polyester resin A that plays the role of an electrode has a high aspect ratio and a long maximum major axis, so that the area of the electrode in terms of a capacitor is large, It is presumed that the retention effect of has become easier to demonstrate.

  In order to exert the effects of the present invention, the toner of the present invention contains polyester resin A and polyester resin B. Polyester resin A is a resin having a portion capable of forming a crystal structure, and polyester resin B is crystalline. It is necessary that the resin does not have a site that can take a structure.

  In order to exert the effect of the present invention, it is necessary that the major axis of the domain having the largest major axis among the domains derived from the polyester resin A is 3.0 μm or more, preferably 4. It is 0 μm or more and 8.0 μm or less. The major axis of the domain having the largest major axis among the domains derived from the polyester resin A is not particularly limited, but can be changed each time according to the average particle diameter of the toner because it is equal to or less than the average particle diameter of the toner particles. In view of the current electrophotographic system, the average particle diameter of the toner particles is preferably 4.5 μm or more and 9.0 μm or less.

  When the maximum major axis of the domains derived from the polyester resin A is less than 3.0 μm, it is presumed that the effect of efficiently transferring the heat applied to the toner surface during fixing to the inside of the toner is reduced. Therefore, the fixability deteriorates under severe fixing conditions such as thick paper fixing. On the other hand, when the average particle diameter of the toner is 9.0 μm and the maximum long diameter of the domain derived from the polyester resin A is 8.0 μm or more, the toner exhibits an effect for fixing a thick paper. However, since the amount of the polyester resin A present on the toner surface increases, charge leakage tends to occur, and the charging stability of the toner tends to deteriorate. Therefore, the maximum major axis of the domain derived from the polyester resin A is preferably in the range of about 1.0 μm shorter than the average particle diameter of the toner.

  In order to exhibit the effects of the present invention, the average aspect ratio (major axis / minor axis) of the polyester resin A domain needs to be 4.0 or more and 20.0 or less, preferably 5.0 or more. 12.0 or less. When the average aspect ratio is less than 4.0, the charge retention effect as a capacitor formed by the polyester resin A and the polyester resin B is diminished, so that charge leakage occurs and the charge deteriorates after being left standing. When the average aspect ratio exceeds 20.0, each of the polyester resin A domains becomes too thin, and the effect of transferring the heat applied to the toner surface to the inside of the toner is diminished. Then, fixability deteriorates.

The maximum diameter and average aspect ratio of the polyester resin A domain in the present invention can be determined by performing cross section observation of the toner using a transmission electron microscope (TEM). The measuring method is not limited, and it is only necessary to observe the cross section of the domain of the polyester resin A.

  Specifically, the toner is embedded with a visible light curable embedding resin (D-800, manufactured by Nissin EM), cut to a thickness of 60 nm with an ultrasonic ultramicrotome (EM5, manufactured by Leica), and a vacuum dyeing apparatus. Ru staining was performed by (Filgen). Thereafter, observation was performed with a transmission electron microscope (H7500, manufactured by Hitachi) at an acceleration voltage of 120 kV. The toner to be observed was photographed by selecting 50 toners having a weight average particle diameter within ± 2.0 μm. In the case of the configuration of the present invention, when Ru dyeing is performed, the polyester resin A in the toner is darker and darker than the polyester resin B, and when wax is used, the wax is projected darker. The maximum major axis and the average aspect ratio of the domain made of the polyester resin A can be determined from the observed image, but the average aspect ratio can be calculated using image processing software as necessary.

  Image-Pro Plus 5.1J (Media Cybernetics) was used as the image processing software. A cross-sectional image of toner particles photographed by the method described above is used. First, in order to extract the toner particles to be analyzed, the toner particle portion is selected in order to separate the toner particles from the background portion. Select “Measurement”-“Count / Size” of Image-Pro Plus 5.1J. From the “Count / Size” window, select “Measurement”-“Measurement Item”. Select “Diameter (minimum)” and “Diameter (maximum)” from the measurement items. In “brightness range selection”, it is necessary to adjust the brightness range so that only the polyester resin A is selected. Depending on the conditions of Ru dyeing, the luminance range must be changed each time, but the polyester resin A can be easily discriminated by the above-described difference in shading. Select “Count” to display the measurement result. Thereafter, the obtained “diameter (minimum)” is defined as the minor axis, and the “diameter (maximum)” is defined as the major axis to determine the aspect ratio (major axis / minor axis). When counting, select “4 linked” in the “Count / Size” extraction option, enter “Smoothness 8”, and check “Fill hole” to select polyester resin A. Is easier to do. From the data of the aspect ratio of one toner particle thus obtained, an average value of 10 points was calculated in order from the one with the largest diameter (maximum), and the average value of the aspect ratio was repeated for 10 toner particles.

Furthermore, in order for the toner to exert the effects of the present invention, the melting point Ta of the polyester resin A and the softening point Tb of the polyester resin B must satisfy the following formula 1.
Ta <Tb Formula 1

  The polyester resin A exhibits a plasticizing effect on the polyester resin B only when heated at a temperature equal to or higher than the melting point as in fixing, and fixes the toner as compared with the case where the polyester resin B is used alone. This has the effect of further improving the performance. When the polyester resin A and the polyester resin B do not satisfy the relationship represented by the formula 1, since the polyester resin B softens first, the plasticizing effect due to the addition of the polyester resin A is reduced, which is not preferable. . The melting point of the polyester resin A can be calculated from an endothermic peak measured at the time of temperature increase in differential scanning calorimetry (DSC) measurement. Further, the softening point of the polyester resin B can be measured by using the temperature at which half of the resin flows out by the flow tester as the softening point.

  In order to bring the domain shape in the toner made of the polyester resin A into the range of the present invention, for example, there is a method of subjecting the toner particles to a thermal spheroidization treatment. In the present invention, the thermal spheronization means that the toner particles are instantaneously present in high-temperature hot air in a state where the toner particles are diffused in the air, and immediately thereafter, the spheroidization is performed by cooling with cold air. Is the method.

  When thermal spheronization is performed, the dispersion state of the polyester resin A tends to be in a desired range in the present invention. The apparatus for performing the thermal spheronization is not particularly limited, and examples thereof include a surffusion system (manufactured by Nippon Neuromatic Industry Co., Ltd.) and meteor embo As a method of heat spheronization, a method of treating with hot air at a temperature equal to or higher than the softening point of the polyester resin B in a short time and then rapidly cooling is preferable. The temperature of the hot air is preferably 100 ° C. or higher and lower than 400 ° C. This is because the polyester resin B and the polyester resin A are melted together, so that the dispersed polyester resin A is aggregated, and the maximum major axis of the domain is increased while maintaining the aspect ratio of the polyester resin A. It is assumed that there is. When the dispersion state of the polyester resin A is changed by annealing as in the prior art, the polyester resin B is not plasticized, and only the polyester resin A dispersed in the toner is plasticized. Therefore, the maximum major axis of the polyester resin A domain does not change, and the aspect ratio becomes small due to the surface tension. Therefore, the dispersion state of the polyester resin A cannot be within the desired range of the present invention. Therefore, it is necessary to perform the thermal spheronization process by the above method.

In order to make the domain shape in the toner derived from the polyester resin A within the scope of the present invention, the SP value Sa of the polyester resin A ((cal / cm ³ ) ^{1 / 2} ) and the SP value Sb ((cal / cm ³ ) ^1/2 ) of the polyester resin B can be achieved within a certain range. Specifically, the SP value Sa of the polyester resin A and the SP value Sb of the polyester resin B satisfy the relationship represented by the following formula 2.
−0.40 ≦ Sb−Sa ≦ 0.80 Formula 2

  More preferably, Sb-Sa is 0.2 to 0.5. In this case, it is possible to achieve a desired range for the domain shape without using the thermal spheronization treatment.

  Sb-Sa is an index showing the ease of compatibility of the polyester resin A and the polyester resin B and the ease of phase separation. The SP value (solubility parameter) is conventionally used as an index indicating the ease of mixing between resins and between resin and wax. When Sb-Sa is less than -0.40, the polyester resin A and the polyester resin B are easily compatible with each other in the toner, and the crystallization of the polyester resin A hardly occurs. Is difficult to grow. Further, when Sb-Sa exceeds 0.80, the polyester resin A and the polyester resin B cause phase separation, and the aspect ratio of the domain of the polyester resin A in the toner tends to be reduced by the surface tension. . When Expression 2 is satisfied, the polyester resin A can exist in both a compatible state and a separated state with respect to the polyester resin B. Therefore, crystallization of the polyester resin A occurs and the maximum major axis of the domain becomes large. However, since the aspect ratio remains small, the range of the present invention is easily satisfied.

  Note that the SP value used in the present invention is a commonly used Fedors method [Poly. Eng. Sci. , 14 (2) 147 (1974)], and calculated from the types and ratios of the monomers constituting the resin. The SP value of the polyester resin A represents the SP value of the polyester molecular chain excluding the crystal nucleating agent.

The polyester resin A is not particularly limited as long as the polyester molecular chain has a portion capable of taking a crystal structure.
In addition, having the part which can take the crystal structure said by this invention means that the said resin has an endothermic peak at the time of temperature rise in differential scanning calorimeter (DSC) measurement, and has an exothermic peak at the time of temperature fall, The measurement The measurement is performed according to the “ASTM D3418-82” measurement method.

The alcohol component which is a raw material monomer contains an aliphatic diol having 6 to 18 carbon atoms from the viewpoint of enhancing the crystallinity of the polyester molecular chain.
Examples of the aliphatic diol having 6 to 18 carbon atoms include 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11 -Undecanediol, 1,12-dodecanediol, etc. are mentioned. Among these, an aliphatic diol having 6 to 12 carbon atoms is preferable from the viewpoint of fixability and heat stability.

  Moreover, it is preferable that content of the said C6-C12 aliphatic diol is 85 mol% or more in all the alcohol components from a viewpoint of raising the crystallinity of the polyester resin A more.

（式中、Ｒは、炭素数２又は３のアルキレン基を示す。ｘ及びｙは、正の数を示し、ｘとｙの和は、１〜１６、好ましくは１．５〜５である。） Examples of the polyhydric alcohol component other than the aliphatic diol having 6 to 18 carbon atoms that can be used as the alcohol component include, for example, a polyoxypropylene adduct of 2,2-bis (4-hydroxyphenyl) propane, 2,2- Aromatic diols such as alkylene oxide adducts of bisphenol A represented by the following formula (I) including polyoxyethylene adducts of bis (4-hydroxyphenyl) propane; 3 such as glycerin, pentaerythritol, trimethylolpropane, etc. Alcohols having a value higher than that are listed.

(In formula, R shows a C2-C3 alkylene group. X and y show a positive number, and the sum of x and y is 1-16, Preferably it is 1.5-5. )

Moreover, as a carboxylic acid component which is a raw material monomer, from a viewpoint of improving the crystallinity of the polyester resin A, a C6-C18 aliphatic dicarboxylic acid compound is preferable.
Examples of the aliphatic dicarboxylic acid compound having 6 to 18 carbon atoms include 1,8-octanedioic acid, 1,9-nonanedioic acid, 1,10-decanedioic acid, 1,11-undecanedioic acid, 1,12- And dodecanedioic acid. Among these, an aliphatic dicarboxylic acid compound having 6 to 12 carbon atoms is preferable from the viewpoint of toner fixing properties and heat stability.

  Moreover, it is preferable that content of a C6-C12 aliphatic dicarboxylic acid compound is 85 mol% or more in all the carboxylic acid components.

  In this invention, carboxylic acid components other than a C6-C18 aliphatic dicarboxylic acid compound can be used together. For example, an aromatic dicarboxylic acid compound, a trivalent or higher valent aromatic polycarboxylic acid compound, and the like can be mentioned, but the invention is not particularly limited thereto.

  The aromatic dicarboxylic acid compound also includes an aromatic dicarboxylic acid derivative that can become the same structural unit as the structural unit derived from the aromatic dicarboxylic acid by a condensation reaction. Specific examples of the aromatic dicarboxylic acid compound preferably include aromatic dicarboxylic acids such as phthalic acid, isophthalic acid and terephthalic acid, anhydrides of these acids, and alkyl (C1 to C3) esters thereof. Examples of the alkyl group in the alkyl ester include a methyl group, an ethyl group, a propyl group, and an isopropyl group.

  Examples of the trivalent or higher polyvalent carboxylic acid compounds include 1,2,4-benzenetricarboxylic acid (trimellitic acid), 2,5,7-naphthalenetricarboxylic acid, and aromatic carboxylic acids such as pyromellitic acid, and these Derivatives such as acid anhydrides and alkyl (1 to 3 carbon atoms) esters may be mentioned.

The polyester resin A contains an alcohol component containing an aliphatic diol having 6 to 12 carbon atoms in an amount of 85 mol% or more and an aliphatic carboxylic acid having 6 to 12 carbon atoms in the total carboxylic acid component. It is preferably a polyester resin obtained by polycondensation with a dicarboxylic acid component containing 85 mol% or more.
The molar ratio (carboxylic acid component / alcohol component) between the alcohol component and the carboxylic acid component, which are raw material monomers for the condensation polymerization reaction, is preferably 0.80 or more and 1.20 or less.

  In the present invention, the weight average molecular weight of the polyester resin A is preferably 8,000 or more and 1,000,00 or less from the viewpoint of toner fixing property and heat-resistant storage stability.

  Further, the melting point of the polyester resin A is 60 ° C. or higher and 120 ° C. or lower, preferably 70 ° C. or higher and 90 ° C. or lower, from the viewpoint of low-temperature fixability of the toner.

  Further, the acid value of the polyester resin A is preferably 2 mgKOH / g or more and 40 mgKOH / g or less from the viewpoint of good charging characteristics of the toner.

  Further, the hydroxyl value of the polyester resin A is preferably 2 mgKOH / g or more and 40 mgKOH / g or less from the viewpoints of fixability and storage stability.

  The toner of the present invention preferably uses a crystal nucleating agent for the purpose of increasing the crystallinity of the polyester resin A. Known crystal nucleating agents can be used, and both inorganic crystal nucleating agents and organic crystal nucleating agents can be used. Specifically, examples of the inorganic crystal nucleating agent include silica, talc, kaolin, alumina, alum, and titanium oxide. Organic crystal nucleating agents include dibenzylidene sorbitol, bis (p-methylbenzylidene) sorbitol, lower alkyl dibenzylidene sorbitol such as bis (p-ethylbenzylidene) sorbitol, or aluminum benzoate compound, phosphate metal salt compound, linear chain Examples include fatty acid metal salts and rosin acid metal salts.

  The crystal nucleating agent may be bonded to the molecular terminal of the polyester resin A. The crystal nucleating agent site is not particularly limited as long as it is bonded to the polyester molecule terminal of the polyester resin A, but is an aliphatic carboxylic acid having 10 to 30 carbon atoms and / or an aliphatic having 10 to 30 carbon atoms. It is preferably a site derived from alcohol. It is preferable that the crystal nucleating agent site has a certain number or more of carbons because the crystal nucleating agent site itself has high crystallinity.

  About the addition amount of a crystal nucleating agent, it is preferable to contain 0.1 mol or more and 10.0 mol or less of a crystal nucleating agent with respect to 100 mol of raw material monomers in the polyester resin A from a viewpoint of raising the crystallization speed.

  As the polyester resin B used in the toner of the present invention, a known polyester resin obtained by a normal production method can be used.

  Examples of the divalent alcohol component include the above-mentioned formulas including 2,2-bis (4-hydroxyphenyl) propane polyoxypropylene adduct, 2,2-bis (4-hydroxyphenyl) propane polyoxyethylene adduct, and the like. An alkylene oxide adduct of bisphenol A represented by (I), ethylene glycol, 1,3-propylene glycol, neopentyl glycol, or the like can be used.

  As the trivalent or higher alcohol component, for example, sorbitol, pentaerythritol, dipentaerythritol and the like can be used.

  In the production of the polyester resin B applied to the present invention, these divalent alcohol components and trihydric or higher polyhydric alcohol components can be used alone or a plurality of monomers can be used.

  Examples of the divalent carboxylic acid component as the acid component include maleic acid, fumaric acid, phthalic acid, isophthalic acid, terephthalic acid, succinic acid, adipic acid, n-dodecenyl succinic acid, and anhydrides or lower of these acids. Examples include alkyl esters.

  Examples of the trivalent or higher polyvalent carboxylic acid component include 1,2,4-benzenetricarboxylic acid, 2,5,7-naphthalenetricarboxylic acid, pyromellitic acid, emporic trimer acid and acid anhydrides thereof, lower Examples include alkyl esters.

  The manufacturing method of polyester is not specifically limited, It can manufacture by esterification reaction or transesterification reaction using said each monomer. When polymerizing the raw material monomer, a commonly used esterification catalyst such as dibutyltin oxide may be appropriately used in order to accelerate the reaction.

The glass transition temperature (Tg) of the polyester resin B is preferably 45 ° C. or higher and 70 ° C. or lower from the viewpoint of fixability and storage stability.
The softening point of the polyester resin B is 80 ° C. or higher and 130 ° C. or lower, preferably 90 ° C. or higher and 120 ° C. or lower, from the viewpoint of low-temperature fixability of the toner. The polyester resin B preferably has a weight average molecular weight of 3,000 to 100,000 in gel permeation chromatography (GPC) soluble in tetrahydrofuran (THF).

  Further, the acid value of the polyester resin B is preferably 2 mgKOH / g or more and 40 mgKOH / g or less from the viewpoint of good charging characteristics of the toner, and the hydroxyl value is from the viewpoint of toner fixing property and storage stability. It is preferable that it is 2 mgKOH / g or more and 40 mgKOH / g or less.

  The mass ratio of the polyester resin A and the polyester resin B is preferably 5:95 to 40:60 from the viewpoint of low-temperature fixability of the toner and long-term storage stability of the image.

In the present invention, a wax can be used as necessary to give the toner releasability.
As the wax, hydrocarbon waxes such as low molecular weight polyethylene, low molecular weight polypropylene, microcrystalline wax, and paraffin wax are preferable because of easy dispersion in the toner and high releasability. If necessary, one or two or more kinds of waxes may be used together in a small amount.

  Specific examples include the following. Biscol (registered trademark) 330-P, 550-P, 660-P, TS-200 (Sanyo Chemical Industries), high wax 400P, 200P, 100P, 410P, 420P, 320P, 220P, 210P, 110P (Mitsui Chemicals) ), Sazole H1, H2, C80, C105, C77 (Schumann Sazol), HNP-1, HNP-3, HNP-9, HNP-10, HNP-11, HNP-12 (Nippon Seiki Co., Ltd.), Unilin (registered trademark) 350, 425, 550, 700, Unicid (registered trademark), Unicid (registered trademark) 350, 425, 550, 700 (Toyo Petrolite), wood wax, beeswax, rice wax, candelilla wax Carnauba wax (available from Celerica NODA).

  The timing of adding the wax may be added at the time of melt kneading during the production of the toner, or may be at the time of producing the polyester resin B, and is appropriately selected from existing methods. These waxes may be used alone or in combination.

  The wax is preferably added in an amount of 1 to 20 parts by mass with respect to 100 parts by mass of the binder resin.

  The toner of the present invention may be a magnetic toner or a non-magnetic toner. When used as a magnetic toner, it is preferable to use magnetic iron oxide. As the magnetic iron oxide, iron oxide such as magnetite, maghemite, and ferrite is used. In addition, for the purpose of improving the fine dispersibility in the toner particles, it is preferable that the magnetic iron oxide is subjected to a treatment of shearing the slurry during production to loosen the magnetic iron oxide.

  In the present invention, the amount of magnetic iron oxide contained in the toner is preferably 25% by mass or more and 45% by mass or less, more preferably 30% by mass or more and 45% by mass or less in the toner.

  When used as a non-magnetic toner, carbon black and other conventionally known pigments and dyes, or one or more of them can be used as the colorant.

  The amount of the colorant to be used is preferably 0.1 parts by mass or more and 60.0 parts by mass or less, and more preferably 0.5 parts by mass or more and 50.0 parts by mass or less with respect to 100.0 parts by mass of the resin component.

In the toner of the present invention, a fluidity improver having high fluidity-imparting ability to the toner particle surface can be used as the inorganic fine powder. As the fluidity improver, any fluidity improver can be used as long as the fluidity can be increased by adding the toner particles externally before and after the addition. For example, the following are mentioned. Fluorine resin powders such as vinylidene fluoride fine powder and polytetrafluoroethylene fine powder; wet-process silica, fine-powder silica such as dry-process silica, these silicas by silane coupling agent, titanium coupling agent, or silicone oil Treated silica with surface treatment. A preferred fluidity improver is a fine powder produced by vapor phase oxidation of a silicon halogen compound, and is referred to as dry process silica or fumed silica. For example, the thermal decomposition oxidation reaction of silicon tetrachloride gas in oxygen and hydrogen is utilized, and the reaction formula is as follows.
SiCl ₄ + 2H ₂ + O ₂ → SiO ₂ + 4HCl

  Further, in this production process, a composite fine powder of silica and another metal oxide obtained by using another metal halogen compound such as aluminum chloride or titanium chloride together with a silicon halogen compound may be used.

  Furthermore, it is preferable to use a treated silica fine powder obtained by hydrophobizing a silica fine powder produced by vapor phase oxidation of the silicon halogen compound. Among the treated silica fine powders, those obtained by treating the silica fine powder so that the degree of hydrophobicity titrated by a methanol titration test is in the range of 30 to 98 are particularly preferable.

  As a hydrophobizing method, it is applied by chemically treating with an organosilicon compound that reacts or physically adsorbs with silica fine powder. As a preferred method, silica fine powder produced by vapor phase oxidation of a silicon halogen compound is treated with an organosilicon compound. Examples of such organosilicon compounds include the following. Hexamethyldisilazane, trimethylsilane, trimethylchlorosilane, trimethylethoxysilane, dimethyldichlorosilane, methyltrichlorosilane, allyldimethylchlorosilane, allylphenyldichlorosilane, benzyldimethylchlorosilane, bromomethyldimethylchlorosilane, α- Chlorethyltrichlorosilane, β-chloroethyltrichlorosilane, chloromethyldimethylchlorosilane, triorganosilyl mercaptan, trimethylsilyl mercaptan, triorganosilyl acrylate, vinyldimethylacetoxysilane, dimethylethoxysilane, dimethyldimethoxysilane, diphenyldiethoxysilane, 1 -Hexamethyldisiloxane, 1,3-divinyltetramethyldisiloxane, 1,3-diphenyltetramethyl Ludisiloxane and dimethylpolysiloxane containing 2 to 12 siloxane units per molecule and containing hydroxyl groups bonded to one Si at each terminal unit. These are used alone or in a mixture of two or more.

  The silica fine powder may be treated with silicone oil, or may be treated in combination with the hydrophobic treatment.

As a preferable silicone oil, one having a viscosity at 25 ° C. of 30 mm ² / s or more and 1000 mm ² / s or less is used. For example, dimethyl silicone oil, methylphenyl silicone oil, α-methylstyrene modified silicone oil, chlorophenyl silicone oil, and fluorine modified silicone oil are particularly preferred.

  Examples of the method for treating silicone oil include the following methods. A method in which silica fine powder treated with a silane coupling agent and silicone oil are directly mixed using a mixer such as a Henschel mixer. A method of spraying silicone oil onto silica fine powder as a base. Alternatively, after dissolving or dispersing silicone oil in a suitable solvent, silica fine powder is added and mixed to remove the solvent. More preferably, the silicone oil-treated silica is heated to 200 ° C. or higher (more preferably 250 ° C. or higher) in an inert gas to stabilize the surface coating after the silicone oil treatment.

  A preferred silane coupling agent is hexamethyldisilazane (HMDS).

  In the present invention, the silica is preferably treated by a method in which silica is treated with a coupling agent and then treated with silicone oil, or a method in which silica is treated with a coupling agent and silicone oil at the same time.

  The inorganic fine powder is used in an amount of 0.01 to 8.00 parts by weight, preferably 0.10 to 4.00 parts by weight, based on 100.00 parts by weight of the toner particles.

  Other external additives may be added to the toner of the present invention as necessary. For example, there are resin fine particles and inorganic fine particles that function as a charge auxiliary agent, conductivity imparting agent, fluidity imparting agent, anti-caking agent, release agent at the time of fixing with a heat roller, lubricant, and abrasive.

  Examples of the lubricant include polyfluorinated ethylene powder, zinc stearate powder, and polyvinylidene fluoride powder. Of these, polyvinylidene fluoride powder is preferred. Examples of the abrasive include cerium oxide powder, silicon carbide powder, and strontium titanate powder. These external additives can be sufficiently mixed using a mixer such as a Henschel mixer to obtain the toner of the present invention.

  The toner of the present invention can be used as a one-component developer, but can also be mixed with a magnetic carrier and used as a two-component developer.

  Examples of the magnetic carrier include iron powder with oxidized surface or non-oxidized iron powder; metal particles such as iron, lithium, calcium, magnesium, nickel, copper, zinc, cobalt, manganese, rare earth, and alloy particles thereof. Commonly known materials such as magnetic particles such as oxide particles; ferrite; and a magnetic material-dispersed resin carrier (so-called resin carrier) containing a magnetic material and a binder resin that holds the magnetic material in a dispersed state are used. it can.

  When the toner of the present invention is mixed with a magnetic carrier and used as a two-component developer, the mixing ratio of the magnetic carrier is preferably 2% by mass or more and 15% by mass or less as the toner concentration in the developer.

  The method for producing the toner of the present invention is not particularly limited, but a production process in which the polyester resin A and the polyester resin B are melt-kneaded and cooled and solidified in that the toner has excellent low-temperature fixability. It is preferable that it is a manufacturing method using the crushing method to include.

  It is preferable to mix by adding shear at the time of melt-kneading because the molecular chain of the polyester resin A easily enters the polyester resin B, so that it can be uniformly compatibilized at the time of melting and the low-temperature fixability can be improved.

  In the raw material mixing step, a predetermined amount of polyester resin A, polyester resin B, colorant, other additives, and the like are mixed and mixed as materials constituting the toner particles. Examples of the mixing apparatus include a double-con mixer, a V-type mixer, a drum-type mixer, a super mixer, a Henschel mixer, a nauter mixer, and a mechano hybrid (manufactured by Nippon Coke Industries, Ltd.).

  Next, the mixed material is melt-kneaded to disperse the colorant and the like in the polyester resin. In the melt-kneading step, a batch kneader such as a pressure kneader or a Banbury mixer or a continuous kneader can be used. Due to the advantage of continuous production, single-screw or twin-screw extruders are the mainstream. For example, KTK type twin screw extruder (manufactured by Kobe Steel Co., Ltd.), TEM type twin screw extruder (manufactured by Toshiba Machine Co., Ltd.), PCM kneader (manufactured by Ikekai Tekko), twin screw extruder (manufactured by KC K ), Co-kneader (manufactured by Buss), kneedex (manufactured by Nippon Coke Industries Co., Ltd.) Furthermore, the resin composition obtained by melt-kneading may be rolled with two rolls or the like and cooled with water or the like in the cooling step.

  Next, the cooled product of the resin composition is pulverized to a desired particle size in the pulverization step. In the pulverization step, for example, after coarse pulverization with a pulverizer such as a crusher, a hammer mill, or a feather mill, for example, a kryptron system (manufactured by Kawasaki Heavy Industries), a super rotor (manufactured by Nisshin Engineering), a turbo mill Finely pulverize with a turbomill (made by Turbo Industries) or air jet type fine pulverizer.

  Then, if necessary, classification such as inertial class elbow jet (manufactured by Nippon Steel & Mining Co., Ltd.), centrifugal classification turboplex (manufactured by Hosokawa Micron), TSP separator (manufactured by Hosokawa Micron), Faculty (manufactured by Hosokawa Micron) The toner particles are obtained by classification using a machine or a sieving machine.

  Furthermore, if necessary, desired additives can be sufficiently mixed by a mixer such as a Henschel mixer to obtain the toner of the present invention.

  A method for measuring physical properties of the resin and toner of the present invention is as follows. Examples described later are also based on this method.

<Sample preparation before various measurements>
If the melting point of the polyester resin A and the softening point of the polyester resin B are available, it is preferable to measure with the material. However, even after toner preparation, measurement is possible if the sample is prepared properly. The sample preparation method is not particularly limited, and the following is an example of a method for separating the polyester resin A and the polyester resin B in the toner. If separation is not sufficient, it is necessary to change the conditions as appropriate.
About 1.5 g of toner was weighed and placed in a pre-weighed cylindrical filter paper (for example, trade name No. 86R (size 28 × 100 mm), manufactured by Advantech Toyo Co., Ltd.) and set in a Soxhlet extractor. Extraction was performed for 10 hours using 200 ml of tetrahydrofuran (THF) as a solvent. The THF soluble component was collected, allowed to stand at room temperature for 24 hours, and then filtered to obtain a deposited component (polyester resin A). Next, THF was evaporated from the filtrate using an evaporator to obtain a deposited component (polyester resin B).

<Measurement of weight average molecular weight by GPC>
The column is stabilized in a heat chamber at 40 ° C., THF is flowed through the column at this temperature as a solvent at a flow rate of 1 ml / min, and about 100 μl of the 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 and the count value of a calibration curve prepared from several types of monodisperse polystyrene standard samples. As a standard polystyrene sample for preparing a calibration curve, for example, a standard polystyrene sample having a molecular weight of about 10 ² to 10 ⁷ manufactured by Tosoh Corporation or Showa Denko KK is suitably used. The detector uses an RI (refractive index) detector. As the column, it is preferable to combine a plurality of commercially available polystyrene gel columns. For example, a combination of shodex GPC KF-801, 802, 803, 804, 805, 806, 807, 800P manufactured by Showa Denko Co., Ltd. of _{TSKgel G1000H (H XL), G2000H} (H XL), G3000H (H XL), G4000H (H XL), G5000H (H XL), G6000H (H XL), G7000H (H XL), include a combination of TSKgurd column be able to.

Moreover, a sample is produced as follows.
Place the sample in THF and leave it at 25 ° C. for several hours, then shake it well, mix well with THF (until the sample is no longer integrated), and let stand for more than 12 hours. At that time, the standing time in THF is set to 24 hours. Then, a sample processing filter (pore size of 0.2 μm or more and 0.5 μm or less, for example, Myssho Disc H-25-2 (manufactured by Tosoh Corporation)) can be used as a GPC sample. The sample concentration is adjusted so that the resin component is 0.5 mg / ml or more and 5.0 mg / ml or less.

<Measurement of melting point and heat of fusion of polyester resin and wax>
The melting point of the polyester resin and the wax is the peak temperature of the maximum endothermic peak in the DSC curve measured according to ASTM D3418-82 using a differential scanning calorimeter “Q2000” (manufactured by TA Instruments). The amount of heat obtained from the area is defined as the heat of fusion.
The temperature correction of the device detection unit uses the melting points of indium and zinc, and the correction of heat uses the heat of fusion of indium. Specifically, about 2 mg of a sample is precisely weighed, placed in an aluminum pan, and an empty aluminum pan is used as a reference. Measurement is performed at ° C / min. In the measurement, the temperature is once raised to 200 ° C., subsequently lowered to 30 ° C., and then the temperature is raised again. The maximum endothermic peak temperature of the DSC curve in the temperature range of 30 to 200 ° C. in the second temperature raising process is defined as the melting point and the amount of heat determined from the peak area as the heat of fusion.

<Measurement of Tg of polyester resin>
The Tg of the polyester resin and the toner is measured according to ASTM D3418-82 using a differential scanning calorimeter “Q2000” (manufactured by TA Instruments).
The temperature correction of the device detection unit uses the melting points of indium and zinc, and the correction of heat uses the heat of fusion of indium. Specifically, about 2 mg of a sample is precisely weighed, placed in an aluminum pan, and an empty aluminum pan is used as a reference. Measurement is performed at ° C / min. In the measurement, the temperature is once raised to 200 ° C., subsequently lowered to 30 ° C., and then the temperature is raised again. A specific heat change is obtained in the temperature range of 40 ° C. to 100 ° C. in the second temperature raising process. At this time, the intersection of the intermediate point line of the baseline before and after the change in specific heat and the differential heat curve is defined as the glass transition temperature Tg of the polyester resin.

<Measurement of softening point of polyester resin and toner>
The softening point of the polyester resin and toner is measured using a constant load extrusion type capillary rheometer “Flow Characteristic Evaluation Apparatus Flow Tester CFT-500D” (manufactured by Shimadzu Corporation) according to the manual attached to the apparatus. In this device, while applying a constant load from the top of the measurement sample with the piston, the measurement sample filled in the cylinder is heated and melted, and the melted measurement sample is pushed out from the die at the bottom of the cylinder, and the piston drop amount at this time A flow curve showing the relationship between temperature and temperature can be obtained.
In the present invention, the “melting temperature in the 1/2 method” described in the manual attached to the “flow characteristic evaluation apparatus Flow Tester CFT-500D” is the softening point. The melting temperature in the 1/2 method is calculated as follows. First, ½ of the difference between the piston lowering amount Smax at the time when the outflow ends and the piston lowering amount Smin at the time when the outflow starts is obtained (this is X. X = (Smax−Smin) / 2). And the temperature of the flow curve when the amount of descending piston is the sum of X and Smin in the flow curve is the melting temperature in the 1/2 method.
As a measurement sample, about 1.0 g of a sample is compression-molded at about 10 MPa for about 60 seconds using a tablet molding compressor (for example, NT-100H, manufactured by NPA System) in an environment of 25 ° C. A cylindrical shape having a diameter of about 8 mm is used.
The measurement conditions of CFT-500D are as follows.
Test mode: Temperature rising method Temperature rising rate: 4 ℃ / min
Starting temperature: 50 ° C
Achieving temperature: 200 ° C

<Measurement of acid value of polyester resin>
The acid value is the number of mg of potassium hydroxide necessary for neutralizing the acid contained in 1 g of the sample. The acid value of the polyester resin is measured according to JIS K 0070-1992. Specifically, it is measured according to the following procedure.

(1) Preparation of Reagent 1.0 g of phenolphthalein is dissolved in 90 ml of ethyl alcohol (95 vol%), and ion exchanged water is added to make 100 ml to obtain a phenolphthalein solution.
7 g of special grade potassium hydroxide is dissolved in 5 ml of water, and ethyl alcohol (95 vol%) is added to make 1 l. In order not to touch carbon dioxide, etc., put in an alkali-resistant container and let stand for 3 days, then filter to obtain a potassium hydroxide solution. The obtained potassium hydroxide solution is stored in an alkali-resistant container. The factor of the potassium hydroxide solution was as follows: 25 ml of 0.1 mol / l hydrochloric acid was placed in an Erlenmeyer flask, a few drops of the phenolphthalein solution were added, titrated with the potassium hydroxide solution, and the hydroxide required for neutralization. Determined from the amount of potassium solution. As the 0.1 mol / l hydrochloric acid, one prepared according to JIS K 8001-1998 is used.

(2) Operation (A) Main test 2.0 g of the pulverized polyester resin sample is precisely weighed into a 200 ml Erlenmeyer flask, and 100 ml of a mixed solution of toluene / ethanol (2: 1) is added and dissolved over 5 hours. Subsequently, several drops of the phenolphthalein solution is added as an indicator, and titration is performed using the potassium hydroxide solution. The end point of titration is when the light red color of the indicator lasts for about 30 seconds.
(B) Blank test Titration is performed in the same manner as above except that no sample is used (that is, only a mixed solution of toluene / ethanol (2: 1) is used).

(3) The acid value is calculated by substituting the obtained result into the following formula.
A = [(C−B) × f × 5.61] / S
Here, A: acid value (mgKOH / g), B: addition amount (ml) of a potassium hydroxide solution in a blank test, C: addition amount (ml) of a potassium hydroxide solution in this test, f: potassium hydroxide Solution factor, S: sample (g).

<Measurement of hydroxyl value of polyester resin>
The hydroxyl value is the number of mg of potassium hydroxide required to neutralize acetic acid bonded to a hydroxyl group when 1 g of a sample is acetylated. The hydroxyl value of the polyester resin is measured according to JIS K 0070-1992. Specifically, it is measured according to the following procedure.

(1) Preparation of reagent 25 g of special grade acetic anhydride is placed in a 100 ml volumetric flask, pyridine is added to make a total volume of 100 ml, and shaken sufficiently to obtain an acetylating reagent. The obtained acetylating reagent is stored in a brown bottle so as not to come into contact with moisture, carbon dioxide gas and the like.
Dissolve 1.0 g of phenolphthalein in 90 ml of ethyl alcohol (95 vol%) and add ion exchange water to make 100 ml to obtain a phenolphthalein solution.
Dissolve 35 g of special grade potassium hydroxide in 20 ml of water and add ethyl alcohol (95 vol%) to make 1 liter. In order not to touch carbon dioxide, etc., put in an alkali-resistant container and let stand for 3 days, then filter to obtain a potassium hydroxide solution. The obtained potassium hydroxide solution is stored in an alkali-resistant container. The factor of the potassium hydroxide solution was as follows: 25 ml of 0.5 mol / l hydrochloric acid was placed in an Erlenmeyer flask, a few drops of the phenolphthalein solution were added, titrated with the potassium hydroxide solution, and the hydroxide required for neutralization. Determined from the amount of potassium solution. As the 0.5 mol / l hydrochloric acid, one prepared according to JIS K 8001-1998 is used.

(2) Operation (A) Main test A 1.0 g sample of the pulverized polyester resin is precisely weighed into a 200 ml round bottom flask, and 5.0 ml of the acetylating reagent is accurately added to the sample using a whole pipette. At this time, if the sample is difficult to dissolve in the acetylating reagent, a small amount of special grade toluene is added and dissolved.
A small funnel is placed on the mouth of the flask, and the bottom of the flask is immersed in a glycerin bath at about 97 ° C. and heated. At this time, in order to prevent the temperature of the neck of the flask from rising due to the heat of the bath, it is preferable to cover the base of the neck of the flask with a cardboard having a round hole.
After 1 hour, the flask is removed from the glycerin bath and allowed to cool. After standing to cool, 1 ml of water is added from the funnel and shaken to hydrolyze acetic anhydride. The flask is again heated in the glycerin bath for 10 minutes for further complete hydrolysis. After cooling, wash the funnel and flask walls with 5 ml of ethyl alcohol.
Add several drops of the phenolphthalein solution as an indicator and titrate with the potassium hydroxide solution. The end point of titration is when the light red color of the indicator lasts for about 30 seconds.
(B) Blank test Titration similar to the above operation is performed except that a polyester resin sample is not used.

(3) Substituting the obtained results into the following formula to calculate the hydroxyl value.
A = [{(BC) × 28.05 × f} / S] + D
Here, A: hydroxyl value (mg KOH / g), B: addition amount (ml) of potassium hydroxide solution in blank test, C: addition amount (ml) of potassium hydroxide solution in this test, f: potassium hydroxide Factor of solution, S: sample (g), D: acid value (mgKOH / g) of polyester resin.

<Measurement method of weight average particle diameter (D4)>
The weight average particle diameter (D4) of the toner is determined based on the precise particle size distribution measuring apparatus “Coulter Counter Multisizer 3” (registered trademark, manufactured by Beckman Coulter, Inc.) having a 100 μm aperture tube. Using the attached dedicated software “Beckman Coulter Multisizer 3 Version 3.51” (manufactured by Beckman Coulter, Inc.) for setting and analyzing the measurement data, the measurement data is measured with 25,000 effective channels. Analysis was performed and calculated.
As the electrolytic aqueous solution used for the measurement, special grade sodium chloride is dissolved in ion-exchanged water so as to have a concentration of about 1% by mass, for example, “ISOTON II” (manufactured by Beckman Coulter, Inc.) can be used.
Prior to measurement and analysis, dedicated software was set up as follows.
In the “Standard Measurement Method (SOM) Change Screen” of the dedicated software, set the total count in the control mode to 50000 particles, set the number of measurements once, and set the Kd value to “standard particles 10.0 μm” (Beckman Coulter, Inc.) Set the value obtained using The threshold and noise level are automatically set by pressing the threshold / noise level measurement button. Also, the current is set to 1600 μA, the gain is set to 2, the electrolyte is set to ISOTON II, and the aperture tube flash after measurement is checked.

In the “pulse to particle size conversion setting screen” of the dedicated software, the bin interval is set to logarithmic particle size, the particle size bin is set to 256 particle size bin, and the particle size range is set to 2 μm to 60 μm.
The specific measurement method is as follows.
(1) About 200 ml of the electrolytic aqueous solution is put in a glass 250 ml round bottom beaker exclusively for Multisizer 3, set on a sample stand, and the stirrer rod is stirred counterclockwise at 24 rotations / second. Then, dirt and bubbles in the aperture tube are removed by the “aperture flush” function of the analysis software.
(2) About 30 ml of the electrolytic aqueous solution is put in a glass 100 ml flat bottom beaker, and "Contaminone N" (nonionic surfactant, anionic surfactant, organic builder pH 7 precision measurement is used as a dispersant therein. About 0.3 ml of a diluted solution obtained by diluting a 10% by weight aqueous solution of a neutral detergent for washing a vessel (made by Wako Pure Chemical Industries, Ltd.) 3 times with ion-exchanged water is added.
(3) Two oscillators with an oscillation frequency of 50 kHz are incorporated in a state where the phase is shifted by 180 degrees, and placed in a water tank of an ultrasonic dispersion device “Ultrasonic Disposition System Tetora 150” (manufactured by Nikka Ki Bios Co., Ltd.) having an electrical output of 120 W A fixed amount of ion-exchanged water is added, and about 2 ml of the above-mentioned Contaminone N is added to this water tank.
(4) The beaker of (2) is set in the beaker fixing hole of the ultrasonic disperser, and the ultrasonic disperser is operated. And the height position of a beaker is adjusted so that the resonance state of the liquid level of the electrolyte solution in a beaker may become the maximum.
(5) In a state where the electrolytic aqueous solution in the beaker of (4) is irradiated with ultrasonic waves, about 10 mg of toner is added to the electrolytic aqueous solution little by little and dispersed. Then, the ultrasonic dispersion process is continued for another 60 seconds. In the ultrasonic dispersion, the temperature of the water tank is appropriately adjusted so as to be 10 ° C. or higher and 40 ° C. or lower.
(6) To the round bottom beaker of (1) installed in the sample stand, the electrolyte solution of (5) in which the toner is dispersed is dropped using a pipette, and the measurement concentration is adjusted to about 5%. . The measurement is performed until the number of measured particles reaches 50,000.
(7) The measurement data is analyzed with the dedicated software attached to the apparatus, and the weight average particle diameter (D4) is calculated. The “average diameter” on the analysis / volume statistics (arithmetic average) screen when the graph / volume% is set with the dedicated software is the weight average particle diameter (D4).

  Although the basic configuration and features of the present invention have been described above, the present invention will be specifically described below based on examples. However, this does not limit the embodiment of the present invention.

<Example of production of polyester resin A1>
Into a reaction vessel equipped with a nitrogen introduction tube, a dehydration tube, a stirrer, and a thermocouple, 1,10-decanediol as an alcohol monomer and 1,10-decanedioic acid as an acid monomer are added in amounts shown in Table 1. did.
Then, 1 part by mass of tin dioctylate as a catalyst was added with respect to 100 parts by mass of the total amount of monomers, heated to 140 ° C. in a nitrogen atmosphere, and reacted for 6 hours while distilling off water at normal pressure.
Next, the reaction was carried out while raising the temperature up to 200 ° C. at 10 ° C./hour. After reaching 200 ° C., the reaction was conducted for 2 hours, and then the reaction vessel was depressurized to 5 kPa or less and reacted at 200 ° C. for 3 hours.
Thereafter, the pressure in the reaction vessel was gradually released and returned to normal pressure, and then the crystal nucleating agent (n-octadecanoic acid) shown in Table 1 was added and reacted at 200 ° C. for 2 hours under normal pressure. Thereafter, the inside of the reaction vessel was again decompressed to 5 kPa or less and reacted at 200 ° C. for 3 hours to obtain a polyester resin A1.
Various physical properties of the obtained polyester resin A1 are as shown in Table 2.

<Examples of production of polyester resins A2 to A12>
Except having changed the monomer seed | species, its compounding quantity, and the crystal nucleating agent as shown in Table 1, polyester resin A2 thru | or polyester resin A12 were obtained similarly to the manufacture example of polyester resin A1. These physical properties are as shown in Table 2.

<Manufacture of polyester resin B1>
Into a reaction vessel equipped with a nitrogen introduction tube, a dehydration tube, a stirrer, and a thermocouple, a monomer having a blending amount shown in Table 3 was added, and then dibutyltin was used as a catalyst in an amount of 1.5 mass with respect to 100 mass parts of the total amount of monomers. Part was added.
Next, the temperature was rapidly raised to 180 ° C. at normal pressure in a nitrogen atmosphere, and then water was distilled off while heating from 180 ° C. to 210 ° C. at a rate of 10 ° C./hour to perform polycondensation.
After reaching 210 ° C., the pressure in the reaction vessel was reduced to 5 kPa or less, and polycondensation was performed under the conditions of 210 ° C. and 5 kPa or less to obtain polyester resin B1.
The polymerization time was adjusted so that the softening point of the resin B1 obtained at this time was the value shown in Table 4. Various physical properties of the polyester resin B1 are as shown in Table 4.

<Examples of production of polyester resins B2 to B10>
Except having changed the monomer seed | species and its compounding quantity as described in Table 3, polyester resin B2 thru | or polyester resin B10 were obtained similarly to the manufacture example of polyester resin B1. These physical properties are as shown in Table 4.

<Toner Production Example 1>
Polyester resin A1 20.0 parts by mass Polyester resin B1 80.0 parts by mass Carbon black 5.0 parts by mass Fischer-Tropsch wax (DSC peak temperature 105 ° C) 5.0 parts by mass 3,5-di-t -Aluminum butylsalicylate compound 0.5 mass part After mixing the said material with a Henschel mixer (FM-75 type | mold, Mitsui Miike Kako Co., Ltd. product), it is a twin-screw kneader (Ikegai Iron Works Co., Ltd. PCM-30 type | mold). )) And kneaded under the conditions of a rotation speed of 3.3 s ^-1 and a kneading resin temperature of 120 ° C.

  The obtained kneaded material was cooled and coarsely pulverized to 1 mm or less with a hammer mill to obtain a coarsely pulverized material. The obtained coarsely pulverized product was finely pulverized with a mechanical pulverizer (T-250 manufactured by Turbo Kogyo Co., Ltd.). Further, the obtained finely pulverized powder was classified using a multi-division classifier utilizing the Coanda effect, and negative frictionally chargeable black particles having a weight average particle diameter of 7.0 μm were obtained.

  The obtained black particles were subjected to a thermal spheronization treatment under the condition of a hot air temperature of 200 ° C. in a meteole rainbow (manufactured by Nippon Pneumatic Industry Co., Ltd.) surface treatment device to obtain toner particles.

  To 100 parts by mass of the obtained toner particles, 1.0 part by mass of titanium oxide fine particles having a primary average particle diameter of 50 nm surface-treated with 15% by mass of isobutyltrimethoxysilane and a primary average of which was surface-treated with 20% by mass of hexamethyldisilazane. Toner 1 was obtained by adding 0.8 part by mass of hydrophobic silica fine particles having a particle diameter of 16 nm and mixing with a Henschel mixer (FM-75 type, manufactured by Mitsui Miike Chemical Co., Ltd.). Various physical properties of Toner 1 are as described in Table 5.

<Toner Production Examples 2 to 8, 10, 11, 14, 15>
In Toner Production Example 1, the procedure was the same as in Toner Production Example 1 except that the types of polyester resin A and polyester resin B and the mass ratio of polyester resin A and polyester resin B were changed as shown in Table 5. Toners 2 to 8, 10, 11, 14, and 15 were prepared. Various physical properties of the toners 2 to 8, 10, 11, 14, and 15 are as described in Table 5.

<Toner Production Examples 9, 12, 13, 16, 17>
In Toner Production Example 1, except that the types of polyester resin A and polyester resin B and the mass ratio of polyester resin A and polyester resin B were changed as shown in Table 5 and the thermal spheronization treatment was not performed. In the same manner as in Toner Production Example 1, toners 9, 12, 13, 16, and 17 were produced. Various physical properties of the toners 9, 12, 13, 16, and 17 are as described in Table 5.

<Example 1>
As a machine used for the evaluation in this example, a commercially available color laser printer Color Laser Jet CP4525 (manufactured by HP) was used. The toner of this evaluation machine was changed to the toner 1 manufactured in Toner Production Example 1, and the following evaluation was performed.

(1) Low temperature fixability (fixation using cardboard)
Instead of a commercially available color laser printer Color Laser Jet CP4525 (manufactured by HP), an external fixing device in which the fixing temperature, fixing nip pressure and process speed of the fixing device can be arbitrarily set was used.
A color laser copier paper (manufactured by HAMMERMILL, 216 g / m ² ) was used in an environment of a temperature of 23 ° C. and a relative humidity of 50%, and a black cartridge was used as a cartridge for evaluation. That is, the product toner was extracted from a commercially available black cartridge, the inside of the cartridge was cleaned by air blow, and then the toner 1 of the present invention was filled in a 150 g cartridge for evaluation. In each of the magenta, yellow, and cyan stations, product toner was extracted and magenta, yellow, and cyan cartridges with the remaining toner amount detection mechanism disabled were inserted for evaluation.
Thereafter, a solid black unfixed image was output so that the applied toner amount was 0.6 mg / cm ² . The fixing temperature of the fixing device was 150 ° C., the process speed was set to 300 mm / sec, and the solid black unfixed image was fixed.
The resulting solid black image is rubbed 5 times with Sylbon paper applied with a load of about 100 g. The density reduction rate of the image density before and after the rubbing is less than 10% as fixability A, and the density reduction rate is 5% below. The evaluation was B, C, and D for each increase. The lower the density reduction rate, the better the low-temperature fixability.
The evaluation results are shown in Table 6. In the present invention, the range up to C evaluation is acceptable.
A: The rate of density decrease is less than 10%.
B: The density reduction rate is 10% or more and less than 15%.
C: Density reduction rate is 15% or more and less than 20%.
D: Density reduction rate is 20% or more and less than 25%.
E: Density reduction rate is 25% or more.

(2) Charge stability after standing
Evaluation was performed using a commercially available color laser printer Color Laser Jet CP4525 (manufactured by HP) in an environment of a temperature of 23 ° C. and a relative humidity of 50%. Two black cartridges were used for evaluation. That is, the product toner was extracted from a commercially available black cartridge, the inside of the cartridge was cleaned by air blow, and then the toner 1 of the present invention was filled in a 150 g cartridge (this cartridge is referred to as cartridge 1). This operation was repeated to prepare another similar cartridge (this cartridge is referred to as cartridge 2). In each of the magenta, yellow, and cyan stations, product toner was extracted and magenta, yellow, and cyan cartridges with the remaining toner amount detection mechanism disabled were inserted. First, after inserting the cartridge 1 into the evaluation machine, when the front door of the evaluation machine was closed, the idle rotation for 90 seconds was automatically performed. Next, the triboelectric charge amount (Q / M) of the developer carried on the developer carrying member immediately after the output of the solid white image (the developer is not developed on the photosensitive drum) is the E-SpartAnalyzer Model EST-III. (Trade name; manufactured by Hosokawa Micron Corporation). The number of measured particles was about 3000, and the measurement was performed in an environment of a temperature of 23 ° C. and a relative humidity of 50%. The obtained triboelectric charge amount (Q / M) was defined as Q / M before standing. In addition, the cartridge 2 is used instead of the cartridge 1 and a solid white image is output in the same manner. After that, the cartridge 2 is taken out from the main body of the evaluation machine and developed by leaving it in an environment of a temperature of 23 ° C. and a relative humidity of 50% for 168 hours. The triboelectric charge amount (Q / M) of the developer carried on the agent carrying member was measured with an E-Spart Analyzer. The triboelectric charge (Q / M) obtained at this time was defined as Q / M after standing. The change rate% between the Q / M before being left and the Q / M after being left as the change rate of the charge amount was evaluated as the charge stability after being left. When the rate of change in charge amount was 0% or more and less than 10%, it was regarded as charge stability A after standing. The lower the rate of change in charge amount, the better the charging stability after standing.
The evaluation results are shown in Table 6. In the present invention, the range up to C evaluation is acceptable.
A: The change rate of the charge amount is 0% or more and less than 10%.
B: The change rate of the charge amount is 10% or more and less than 15%.
C: Change rate of charge amount is 15% or more and less than 20%.
D: The change rate of the charge amount is 20% or more and less than 25%.
E: Change rate of charge amount is 25% or more.
In Example 1, good results were obtained in any evaluation of the toner.

<Examples 2 to 12, Comparative Examples 1 to 5>
In Example 1, the evaluation was performed in the same manner as in Example 1 except that the toner used for evaluation was changed to toners 2 to 17 as shown in Table 6 (Examples 2 to 12, Comparative Examples 1 to 5). ). The evaluation results obtained at this time are as shown in Table 6.

1: Toner 1 particle 10: Domain derived from polyester resin A 11: Polyester resin B

Claims (3)

In a toner containing polyester resin A, polyester resin B, and a colorant,
(1) The polyester resin A is a resin having a portion capable of taking a crystal structure,
(2) The polyester resin B is a resin that does not have a portion capable of taking a crystal structure,
(3) In cross-sectional observation of the toner using a transmission electron microscope (TEM), the toner has a domain derived from the polyester resin A on the cross section of the toner, and the major axis of the domain having the largest major axis is the major axis. 3.0 μm or more,
(4) The average aspect ratio (major axis / minor axis) of the domain is 4.0 or more and 20.0 or less,
(5) A toner wherein the melting point Ta of the polyester resin A and the softening point Tb of the polyester resin B satisfy the following formula 1.
Ta <Tb Formula 1   The toner according to claim 1, wherein a mass ratio of the polyester resin A and the polyester resin B is 5:95 to 40:60. The polyester resin A comprises an alcohol component containing an aliphatic diol having 6 to 12 carbon atoms in an amount of 85 mol% or more and an aliphatic dicarboxylic acid having 6 to 12 carbon atoms in the total carboxylic acid component. the toner according to claim 1 or 2 characterized in that it is a polycondensate of a carboxylic acid component, containing more than 85 mole% against.

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