JP2008180874A - Electrostatic charge image development toner, electrostatic charge image developer, toner cartridge, process cartridge, image forming method, and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrostatic charge image development toner capable of suppressing the reduction in a charging amount even if being left from several hours for about ten hours or more after charging treatment. <P>SOLUTION: The electrostatic charge image development toner at least comprises: a crystalline resin; a noncrystalline resin; and an organometallic compound having an alkyl group in which the number of carbon is in the range of 5 to 18. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an electrostatic charge image developing toner, an electrostatic charge image developer, a toner cartridge, a process cartridge, an image forming method, and an image forming apparatus used for forming an image by electrophotography.

In order to meet the recent demand for energy saving, copying machines that form images using electrophotography are required to save more power. In order to save power, it is effective to lower the fixing temperature.
This is because it is possible to suppress power consumption in a standby state (a state in which image formation is possible immediately), in particular, power consumption in a fixing device having a large energy consumption. Also, due to the lower fixing temperature, the time until the fixing machine reaches a temperature at which fixing is possible from room temperature becomes shorter, so the complete stop state (power supply to the device is completely stopped, It is also possible to shorten the time (so-called warm-up time) required to shift from the state in which an image cannot be formed immediately) to the standby state.
Correspondingly, various toners that can be fixed at a lower temperature than in the past have been studied. In order to enable fixing at a low temperature, a crystalline resin is used as a binder resin for the toner. It is generally known. However, from a practical viewpoint, as the binder resin, an amorphous resin is used together with a crystalline resin. For example, a toner composed of a core layer and a shell layer covering the core layer, using a crystalline resin as a binder resin main component of the core layer, and using an amorphous resin as a binder resin of the shell layer is an example. (See Patent Document 1).
Japanese Patent Laying-Open No. 2005-227672.

As exemplified above, the reason why the non-crystalline resin is used together with the crystalline resin as the binder resin for the toner corresponding to fixing at a low temperature is that the crystalline resin is generally lower than the non-crystalline resin. This is because electric resistance is exhibited, so that a decrease in toner charging property caused by the crystalline resin is suppressed. For this reason, in a toner that uses both a crystalline resin and an amorphous resin as a binder resin, if the crystalline resin is not significantly exposed on the surface of the toner, the toner is suitable for image formation by charging treatment. Can be charged to a certain level. However, as a result of intensive studies by the present inventors, once charged to a level suitable for image formation, if left for several hours to more than a dozen hours or more, fogging or the like occurs and the level becomes unsuitable for image formation. It was confirmed that the charge amount was greatly reduced.
The present invention relates to a toner for developing an electrostatic charge image that can suppress a decrease in charge amount even if it is left for several hours to ten or more hours after performing a charging process, and an electrostatic charge image developer using the same, a toner cartridge, It is an object of the present invention to provide a process cartridge, an image forming method, and an image forming apparatus.

The above object is achieved by the present invention described below. That is,
The invention according to claim 1
An electrostatic charge image developing toner comprising at least a crystalline resin, an amorphous resin, and an organometallic compound having an alkyl group having 5 to 18 carbon atoms.

The invention according to claim 2
The organometallic compound having an alkyl group having 5 to 18 carbon atoms is a catalyst used for polymerization of at least one resin selected from the crystalline resin and the amorphous resin. The toner for developing an electrostatic image according to claim 1.

The invention according to claim 3 is:
2. The electrostatic charge according to claim 1, wherein the organometallic compound having an alkyl group having 5 to 18 carbon atoms includes any one metal element selected from Sn element and Ti element. This is an image developing toner.

The invention according to claim 4 is:
2. The electrostatic image developing toner according to claim 1, wherein the crystalline resin is a crystalline polyester resin.

The invention according to claim 5 is:
2. The electrostatic image developing toner according to claim 1, wherein the non-crystalline resin is a non-crystalline polyester resin.

The invention according to claim 6 is:
An electrostatic charge image developer comprising: a toner including at least a crystalline resin, an amorphous resin, and an organometallic compound having an alkyl group having 5 to 18 carbon atoms.

The invention according to claim 7 is:
It is detachable from an image forming apparatus having at least a toner image forming unit, and stores a developer to be supplied to the toner image forming unit.
In the toner cartridge, the developer includes a toner including at least a crystalline resin, an amorphous resin, and an organometallic compound having an alkyl group having 5 to 18 carbon atoms. .

The invention according to claim 8 is:
It is detachable from the image forming apparatus,
An image holding member; and at least a toner image forming unit that contains the developer and supplies the developer to an electrostatic latent image formed on the surface of the image holding member to form a toner image.
The developer is an alkyl group having 5 to 18 carbon atoms dispersed in at least one resin selected from a crystalline resin, an amorphous resin, and the crystalline resin and the amorphous resin. A process cartridge comprising: a toner containing at least an organometallic compound having

The invention according to claim 9 is
A charging step for charging the surface of the image carrier, an electrostatic latent image forming step for forming an electrostatic latent image on the charged surface of the image carrier, and developing the electrostatic latent image with the developer to form a toner image. A toner image forming step for forming the toner image, a transfer step for transferring the toner image to the surface of the recording medium, and a fixing step for fixing the toner image transferred to the surface of the recording medium,
In the image forming method, the developer includes a toner including at least a crystalline resin, an amorphous resin, and an organometallic compound having an alkyl group having 5 to 18 carbon atoms. is there.

The invention according to claim 10 is:
An image carrier, a charging unit that charges the surface of the image carrier, an electrostatic latent image forming unit that forms an electrostatic latent image on the charged surface of the image carrier, and the developer At least a toner image forming unit that forms a toner image by developing, a transfer unit that transfers the toner image to the surface of the recording medium, and a fixing unit that fixes the toner image transferred to the surface of the recording medium,
The developer is an alkyl group having 5 to 18 carbon atoms dispersed in at least one resin selected from a crystalline resin, an amorphous resin, and the crystalline resin and the amorphous resin. And an organic metal compound having at least a toner.

As described above, according to the present invention, according to the first aspect of the present invention, as compared with the case where the present configuration is not provided, it is allowed to stand for several hours to ten or more hours after performing the charging process. Even in this case, it is possible to provide a toner for developing an electrostatic image that can suppress a decrease in charge amount.
According to the second aspect of the present invention, compared to the case where the present configuration is not provided, a decrease in the charge amount can be further suppressed even if the device is left for several hours to tens of hours after performing the charging process. An electrostatic charge image developing toner can be provided.
According to the third aspect of the present invention, an organometallic compound having an alkyl group having 5 to 18 carbon atoms is used for binder resin polymerization of toner, as compared with the case where this configuration is not provided. Therefore, the dispersibility of the organometallic compound having an alkyl group having 5 to 18 carbon atoms in the binder resin can be made more uniform, and in this case, from several hours after the charging treatment is performed. It is possible to provide a toner for developing an electrostatic image that can further suppress a decrease in charge amount even when left for more than ten hours.
According to the fourth aspect of the present invention, it is possible to provide a toner for developing an electrostatic charge image that is excellent in low-temperature fixability particularly on paper as compared with the case where the present configuration is not provided.
According to the invention described in claim 5, compared with the case where this configuration is not provided, the use of an amorphous resin having excellent affinity with the crystalline polyester resin further improves the low-temperature fixability. A toner for developing a charge image can be provided.

  According to the sixth aspect of the present invention, compared to the case where the present configuration is not provided, the electrostatic charge that can suppress the decrease in the charge amount even after being left for several hours to tens of hours or more after performing the charging process. An image developer can be provided.

  According to the seventh aspect of the present invention, even when an image is formed immediately after the complete stop state) as compared with the case where this configuration is not provided, the occurrence of fog or the like due to insufficient charge amount of the toner is caused. It is possible to provide a toner cartridge capable of suppressing and obtaining a good quality image from the beginning of image formation.

According to the eighth aspect of the present invention, as compared with the case where the present configuration is not provided, even when an image is formed immediately after the complete stop state), the occurrence of fog due to insufficient charge amount of the toner is suppressed. In addition, it is possible to provide a process cartridge capable of obtaining a good quality image from the initial stage of image formation.
According to the ninth aspect of the present invention, even when an image is formed immediately after the complete stop state) as compared with the case where this configuration is not provided, the occurrence of fog or the like due to insufficient charge amount of the toner is caused. It is possible to provide an image forming method capable of suppressing and obtaining an image of good quality from the initial stage of image formation.
According to the tenth aspect of the present invention, even when an image is formed immediately after the complete stop state) as compared with the case where this configuration is not provided, the occurrence of fog or the like due to insufficient charge amount of the toner is caused. It is possible to provide an image forming apparatus that can suppress and obtain an image of good quality from the initial stage of image formation.

<Toner for electrostatic image development>
The toner for developing an electrostatic charge image of the present invention (hereinafter sometimes referred to as “toner”) includes a crystalline resin, an amorphous resin, and an organic metal having an alkyl group having 5 to 18 carbon atoms. And at least a compound.
Since the toner of the present invention contains a crystalline resin, it can be fixed in a low temperature range (110 ° C. or more and 140 ° C. or less). This is because the crystalline resin has a property that the melt viscosity is remarkably lowered when the melting point is exceeded. This crystalline resin (particularly a crystalline resin having a weight molecular weight of 5000 or more) has higher hydrophobicity (that is, lower solubility parameter SP value) and higher hydrophilicity (that is, solubility parameter SP) than amorphous resin. It has poor affinity with non-crystalline resin (which has a large value). For this reason, the crystalline resin and the amorphous resin are basically difficult to mix uniformly, and even when these two types of resins are heated and mixed, the phase separation occurs and the domain of the large crystalline resin is amorphous. It tends to be formed in a matrix made of resin.

  On the other hand, the present inventors diligently studied about a toner in which a large domain made of a crystalline resin is formed, and the charge amount tends to be remarkably lowered when left for several hours to ten or more hours after performing the charging process. I understood. This is because when a domain is formed, the domain is also exposed on the toner surface, and the domain exposed on the toner surface becomes a conduction path, and the charge of the toner flows out to the carrier and the developing sleeve. It seems to be because. For this reason, the present inventors considered that it is extremely important to improve the compatibility between the crystalline resin and the amorphous resin in order to prevent the formation of large domains made of the crystalline resin.

  Here, in the present invention, as a substance for improving the compatibility between the crystalline resin and the amorphous resin, an organometallic compound having an alkyl group having 5 to 18 carbon atoms (hereinafter referred to as “compatibility improver”). ”). Although the exact reason why the compatibility improver improves the compatibility of these resins is unknown, the hydrophobic alkyl group portion of the compatibility improver has an affinity for highly hydrophobic crystalline resins. Demonstrates non-hydrophilic alkyl groups (particularly ionic bonds (or bonds with high ionic bonds) formed by metal and organic group containing alkyl groups) are highly hydrophilic and non-crystalline. This is presumed to be due to exhibit affinity with the resin. Therefore, the presence of the compatibility improver in the toner improves the compatibility between the crystalline resin and the amorphous resin, thereby improving the uniformity and temporarily forming the crystalline resin domain. Even so, the size can be further reduced.

  In order for the compatibility improver to perform the above-described function, the compatibility improver needs to be included in a region where the crystalline resin and the amorphous resin are present in the toner. Therefore, when the toner is manufactured, the compatibility improver can be added to the raw material for toner (1) while the crystalline resin and the amorphous resin are mixed. More preferably, the resin and the amorphous resin are preliminarily added to at least one of the resins before being mixed, and (3) both the resins are mixed before the crystalline resin and the amorphous resin are mixed. Most preferably, it is added in advance.

This is because, assuming that the content of the compatibility improver contained in each of the toners produced by the three aspects (1) to (3) is the same in any of the three aspects, In the case of (1), the compatibility improver tends to be unevenly distributed in the resin matrix composed of the crystalline resin and the amorphous resin, so that the compatibility contributes to the improvement of the compatibility between the crystalline resin and the amorphous resin. While the effective amount of the improver is reduced, in the case of (2), since the compatibility improver is already dispersed in one resin, the effect of the compatibility improver that contributes to the improvement of the compatibility is achieved. This is because the amount increases compared to the case of (1), and in the case of (3), the effective amount of the compatibility improver contributing to the improvement of the compatibility is further increased than in the cases of (1) and (2). . In producing the toner of the present invention, the embodiment shown in (2) or (3) and the embodiment shown in (1) may be combined as necessary.
The above-mentioned “mixing of crystalline resin and non-crystalline resin” depends on the toner production method. For example, when a toner is prepared by a kneading pulverization method, two types of resins are mechanically mixed. In the case of using the agglomeration coalescence method, the crystalline resin particles and the amorphous resin particles present in the raw material dispersion (other raw material particles used as necessary) Means mixing in the process of agglomerating to form aggregated particles.

  Further, from the viewpoint described above, the compatibility improver is preferably dispersed as uniformly as possible in a region where the crystalline resin and the amorphous resin are present in the toner. Whether the compatibility improver is uniformly dispersed in the toner can be evaluated by, for example, measuring the cross section of the toner by X-ray photoelectron spectroscopy (XPS). In this case, for example, the compatibility improver at the toner center point and four peripheral portions (positions 1 μm inside from the toner surface to the center point side and 0, 90, 180, and 270 degrees relative to the center point). For example, a method may be used in which the area intensity of the 1s spectrum of the metal ions contained in is measured and the degree of variation with respect to the average value is evaluated.

In order to make the dispersion state of the compatibility improver more uniform in the region where the crystalline resin and the amorphous resin are present in the toner, the compatibility improver is made of a crystalline resin and an amorphous resin. It is preferable that it also serves as a catalyst used for polymerization of at least one selected resin. In this case, it is more preferable that the compatibility improver also functions as a catalyst used for polymerization of both resins. This is because the compatibility improver is used as a catalyst at the stage of resin polymerization with a low viscosity rather than dispersing the compatibility improver in the resin in a state where the viscosity after the resin polymerization is high. The compatibility improver can be more uniformly dispersed. Therefore, even if the charging process is performed for several hours to more than a dozen hours or more, a decrease in charge amount can be further suppressed.
In the case where the compatibility improver is also used as a catalyst during resin polymerization, the type of resin to be polymerized is not particularly limited, but at least one of the crystalline resin and the amorphous resin is a polyester resin. It is preferable that both are polyester resins. When a crystalline polyester resin is used as the crystalline resin, it is possible to obtain a toner that is particularly excellent in low-temperature fixability to paper. In addition, when an amorphous polyester resin is used as the amorphous resin, a toner having further excellent low-temperature fixability can be obtained because of excellent affinity with the crystalline polyester resin.

In addition, a so-called core-shell structure composed of a core layer and a shell layer covering the core layer, using a crystalline resin as a binder resin main component of the core layer and using an amorphous resin as a binder resin of the shell layer. An example of such toner is described (see Patent Document 1). In the toner having the core-shell structure, when the amorphous resin is used for the shell layer, the exposure of the crystalline resin on the toner surface is suppressed. In this case, too, the crystalline resin of the core layer and the non-crystalline property of the shell layer are used. If the compatibility of the resin is insufficient, there is no affinity between the shell and the core, so that a portion where the shell is repelled and is not covered is generated.
However, when the toner of the present invention has the above-described core-shell structure, the compatibility between the crystalline resin and the amorphous resin is improved, so that the formation of the shell layer is improved during the preparation of the toner, and the crystalline resin domain is reduced. In addition, the crystalline resin in the core layer can be suppressed from being exposed to the toner surface.

  Next, various constituent materials constituting the toner, various characteristic values, manufacturing methods, and the like will be described in more detail.

-Compatibility improver-
The number of carbon atoms of the alkyl group constituting the compatibility improver must be 5 or more and 18 or less, and preferably 7 or more and 12 or less. When the number of carbon atoms is less than 5, the affinity between the alkyl group and the crystalline resin is lowered, and the crystalline resin and the amorphous resin cannot be made compatible. Moreover, when the number of carbons exceeds 18, the compatibility improver as a whole becomes too hydrophobic, the affinity with the amorphous resin is lowered, and the crystalline resin and the amorphous resin are made compatible. Can not be. For this reason, in any case, if the toner is left for several hours to more than a dozen hours after being charged, the charge amount is significantly reduced.

Further, when the toner is prepared by using the aggregation and coalescence method described later, if the carbon number of the alkyl group constituting the compatibility improver is less than 5, the aggregation obtained by aggregating the toner raw material in the raw material dispersion In some cases, the coalescence of the crystalline resin and the amorphous resin may be insufficient due to insufficient fusion of the particles or insufficient dispersion of the crystalline resin in the toner.
On the other hand, when the crystalline resin or non-crystalline resin used for the preparation of the toner is a polyester resin, and the compatibility improver is used as a catalyst for polymerizing the polyester resin, the alkyl group constituting the compatibility improver is used. If the number of carbon atoms exceeds 18, the effect as a catalyst for promoting the esterification reaction during resin polymerization is reduced, so that it is difficult to control the molecular weight of the resulting polyester resin, and the molecular weight distribution may be broad.

  The molecular structure of the alkyl group constituting the compatibility improver is not particularly limited, and may be either a branched structure or a straight chain structure, but the alkyl group is likely to be entangled with the crystalline resin molecule, so that the compatibility can be improved more easily. From this point of view, a linear structure is preferable.

In addition, the organic group couple | bonded and / or coordinated with the metal which comprises a compatibility improvement agent should just be 1 or more and 4 or less range, and a compatibility improvement agent has 2 or more organic groups May contain an alkyl group having 5 to 18 carbon atoms in at least one organic group.
Moreover, if it is a metal which comprises a well-known organometallic compound, it will not specifically limit as a metal which comprises a compatibility improvement agent, For example, Sn, Ti, Al, Ca etc. are mentioned.
In JP-A-63-101856, JP-A-61-272758, JP-A-62-287260, JP-A-2005-215271, etc., an organic metal salt containing tin or titanium includes Although it is described that it can be used as a resin polymerization catalyst of a binder resin for toner, from the viewpoint that it can be used as a resin polymerization catalyst, Sn or Ti is used as a metal constituting the compatibility improver. And Sn is most preferable.

In view of the above viewpoint, the compatibility improver includes, for example, hexaethylditin oxide, didodecyltin oxide; a tin compound containing a carboxylate structure (for example, pentanoic acid, hexanoic acid, 2,2-dimethyl) Tin compounds containing carboxylate structures such as propanoic acid, 2-ethylhexanoic acid, heptanoic acid, octanoic acid, nonanoic acid, decanoic acid, tetradecanoic acid, dodecanoic acid, lauric acid, stearic acid, oleic acid); aliphatic mono Titanium carboxylate (for example, titanium octoate); Aliphatic titanium dicarboxylate (for example, titanium adipate, titanium sebacate, etc.); Titanium tricarboxylate (for example, titanium hexanetricarboxylate, titanium isooctanetricarboxylate); , Aliphatic titanium polycarboxylate (eg octanetetracarboxylic Titanium, decane tetracarboxylic acid titanium); organoaluminum compound (e.g., aluminum laurate, may be mentioned aluminum stearate), or the like. In the organic metals listed above, tin, titanium, and aluminum are listed as the metal species, but other metals may be used as long as they have the same valence.
Among the enumerated above, tin 2-ethylhexanoate, tin dioctanoate and tin distearate are particularly preferable. Moreover, a compatibility improver can also be used in combination of 2 or more types.

Further, the content of the compatibility improver contained in the toner is preferably 0.001% by mass or more, and more preferably 0.05% by mass or more. When the content is less than 0.001% by mass, the compatibility between the crystalline resin and the amorphous resin may be insufficient. In addition, although the upper limit of content is not specifically limited, It is preferable that it is 5 mass% or less practically, and it is more preferable that it is 3 mass% or less.
When the compatibility improver is a polyester resin or a crystalline resin or a non-crystalline resin and is also used as a catalyst during the polymerization, the compatibility improver is added to the total amount of monomers used for the polymerization. On the other hand, it is preferably used in the range of 0.01% by mass to 2% by mass, more preferably in the range of 0.05% by mass to 1% by mass, and more preferably 0.1% by mass to 0.7%. More preferably, it is used in the range of mass% or less.
When the amount of the compatibility improver used relative to the total amount of monomers used for the polymerization is less than 0.01% by mass, the reaction time during polyester polymerization becomes longer, and the effect of improving the compatibility between the crystalline resin and the amorphous resin is obtained. It may be difficult to obtain. In addition, the molecular weight distribution of the polyester resin becomes broad, and as a result, the fixability of the resulting toner may deteriorate. On the other hand, if it exceeds 2 mass%, the charging characteristics of the resulting toner will be affected, and the charge amount may vary greatly depending on the environment.

-Crystalline resin-
The crystalline resin is not particularly limited as long as it is a resin having known crystallinity, and specific examples include crystalline polyester resins and crystalline vinyl resins. From the viewpoint of achieving this, a crystalline polyester resin is preferred.
Here, in the present specification, “crystalline resin” refers to having a clear endothermic peak in differential scanning calorimetry (DSC) rather than a stepwise endothermic amount change. It means that the half width of the endothermic peak when measured at a rate of 10 ° C./min is within 6 ° C. On the other hand, “non-crystalline resin” means a resin having a half-value width exceeding 6 ° C. even when an endothermic peak is present, or a resin in which no clear endothermic peak is observed.
The melting point and glass transition temperature of each material such as a crystalline resin and an amorphous resin constituting the toner, and a release agent used as necessary are determined by a differential scanning calorimeter (manufactured by Shimadzu Corporation: DSC-50). ) And measured under a temperature rising rate of 10 ° C./min. At this time, the melting point is obtained as the temperature at the top of the endothermic peak, and the glass transition temperature is the temperature at the intersection of the extended line of the base line and the rising line of the endothermic peak (the line on the low temperature side with respect to the peak top). As sought.

The melting point of the crystalline resin is preferably in the range of 50 ° C to 130 ° C, and more preferably in the range of 60 ° C to 90 ° C. When the melting point is less than 50 ° C., the toner blocking property may be deteriorated, and when it is higher than 130 ° C., fixing in a low temperature region may be difficult. The crystalline resin may show a plurality of melting peaks, but in the present invention, the maximum peak is regarded as the melting point.
Further, the weight average molecular weight (Mw) of the crystalline resin is preferably in the range of 5,000 to 100,000 in terms of molecular weight measurement by a gel permeation chromatography (GPC) method in which tetrahydrofuran (THF) is soluble. It is preferable that it is the range of 50000 or less. On the other hand, the number average molecular weight (Mn) is preferably in the range of 2,000 or more and 10,000 or less as measured by GPC method.
The molecular weight distribution Mw / Mn is preferably in the range of 1.5 to 100, and preferably in the range of 2 to 20.

  When the weight average molecular weight or the number average molecular weight is smaller than the above range, the fixability in the low temperature range is excellent, but the resin is low and soft, and the toner may be blocked and the storage stability may be deteriorated. On the other hand, if the weight average molecular weight or number average molecular weight exceeds the above range, the squeezing out of the crystalline resin from the toner becomes insufficient at the time of fixing, which may adversely affect document storage stability. There is also.

  The content of the crystalline resin in the toner is preferably included in the range of 2% by mass or more and 40% by mass or less, and is preferably included in the range of 3% by mass or more and 20% by mass or less. If the content is less than 2% by mass, fixing in a low temperature range may be insufficient, and if it exceeds 40% by mass, the mechanical strength of the toner becomes insufficient, and filming on the surface of the image carrier tends to occur. Or the obtained image may be easily destroyed.

-Amorphous resin-
The non-crystalline resin is not particularly limited as long as it is a known non-crystalline resin, and a known resin material can be used. By using an amorphous resin together with a crystalline resin as a binder resin, it is possible to ensure the strength and chargeability required for the toner.
Examples of the amorphous resin include styrenes such as styrene, parachlorostyrene, and α-methylstyrene; methyl acrylate, ethyl acrylate, butyl acrylate, propyl acrylate, lauryl acrylate, ethyl hexyl acrylate, and methacrylic acid. Esters having a vinyl group such as methyl, ethyl methacrylate, butyl methacrylate, propyl methacrylate, lauryl methacrylate, ethyl hexyl methacrylate, vinyl acetate, vinyl benzoate; methyl maleate, ethyl maleate, butyl maleate, etc. Carboxylic acids having a double bond; olefins such as ethylene, propylene, butylene and butadiene; carboxylic acids having a double bond such as acrylic acid, methacrylic acid and maleic acid; Polymerized Things, more can be mentioned a mixture of these.

  Furthermore, epoxy resins, melamine resins, polyester resins, polyurethane resins, polyamide resins, cellulose resins, polyether resins, etc., non-vinyl condensation resins, or a mixture of these with the above vinyl resins or in the coexistence of these, Examples thereof include a graft polymer obtained when the monomer is polymerized. Of the non-crystalline resins listed above, a polyester resin is particularly preferable from the viewpoint of facilitating fixing in a low temperature range.

  The glass transition temperature of the amorphous resin is preferably in the range of 40 ° C. or higher and 80 ° C. or lower. From the viewpoint of the balance between storage stability and toner fixing property, it is preferably 50 ° C. or higher and 70 ° C. or lower. More preferred. If the glass transition temperature is less than 40 ° C., the toner may be blocked during storage or in a developing device (a phenomenon in which toner particles are aggregated into a lump). On the other hand, if the glass transition temperature exceeds 80 ° C., the fixing temperature of the toner is high, and fixing in a low temperature region may be difficult.

Further, the weight average molecular weight (Mw) of the amorphous resin is preferably from 5,000 to 100,000, preferably 10,000 or more, as determined by a gel permeation chromatography (GPC) method in which tetrahydrofuran (THF) is soluble. The number average molecular weight (Mn) is more preferably 2000 or more and 10,000 or less. Furthermore, the molecular weight distribution Mw / Mn is preferably from 1.5 to 100, more preferably from 2 to 20.
When the weight average molecular weight or the number average molecular weight is smaller than the above range, the fixability in the low temperature range is excellent, but the hot offset resistance may be deteriorated. On the other hand, when the weight average molecular weight or the number average molecular weight exceeds the above range, the hot offset resistance can be sufficiently secured, but the fixability in a low temperature region may be lowered. In addition to this, since the bleeding of the crystalline polyester present in the toner at the time of fixing is inhibited, there is a possibility of adversely affecting the document storage stability.

  The molecular weight distribution of the crystalline resin and the amorphous resin was performed under the following conditions. First, GPC uses “HLC-8120GPC, SC-8020 (manufactured by Tosoh Corporation)” apparatus, and two columns are “TSKgel, SuperHM-H (6.0 mm ID × 15 cm, manufactured by Tosoh Corporation)”. And THF (tetrahydrofuran) was used as the eluent. As experimental conditions, an experiment was performed using a sample concentration of 0.5%, a flow rate of 0.6 ml / min, a sample injection amount of 10 μl, a measurement temperature of 40 ° C., and an IR detector. The calibration curve is “polystylen standard sample TSK standard” manufactured by Tosoh Corporation: “A-500”, “F-1”, “F-10”, “F-80”, “F-380”, “A-2500”. ”,“ F-4 ”,“ F-40 ”,“ F-128 ”, and“ F-700 ”.

The content of the amorphous resin in the toner is preferably included in the range of 50% by mass to 90% by mass, and more preferably in the range of 70% by mass to 90% by mass. If the content is less than 50% by mass, the toner strength and chargeability may not be sufficiently secured, and if it exceeds 90% by mass, fixing in a low temperature region may be difficult.

-Polyester resin-
As the crystalline resin or non-crystalline resin, it is preferable to use a polyester resin as described above. In this case, at least one of the crystalline resin and the amorphous resin used as the binder resin is preferably a polyester resin, but it is particularly preferable that both are polyester resins.

The polyester resin used for the toner is not particularly limited, and a known polyester resin material can be used.
The polyester resin is polymerized from a polyvalent carboxylic acid component and a polyhydric alcohol component. In preparing the toner, a commercially available polyester resin may be used as the polyester resin, or a polymerized one may be used as necessary.

Examples of the polyvalent carboxylic acid component include oxalic acid, succinic acid, glutaric acid, adipic acid, peric acid, azelaic acid, sebacic acid, 1,9-nonanedicarboxylic acid, 1,10-decanedicarboxylic acid, 1,12 -Aliphatic dicarboxylic acids such as dodecanedicarboxylic acid, 1,14-tetradecanedicarboxylic acid, 1,18-octadecanedicarboxylic acid, phthalic acid, isophthalic acid, terephthalic acid, naphthalene-2,6-dicarboxylic acid, malonic acid, mesaconic acid Aromatic dicarboxylic acids such as dibasic acids such as, and the like, and anhydrides and lower alkyl esters thereof are also included, but not limited thereto.
Examples of the trivalent or higher carboxylic acid include 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, and the like, and anhydrides thereof. And lower alkyl esters. These may be used individually by 1 type and may use 2 or more types together.

As the acid component, in addition to the aliphatic dicarboxylic acid and aromatic dicarboxylic acid described above, a dicarboxylic acid component having a sulfonic acid group may be conventionally used in the polymerization of a polyester resin for toner. This is because a dicarboxylic acid having a sulfonic acid group can favorably disperse a colorant such as a pigment. On the other hand, if the sulfonic acid group is present in the polyester resin, the chargeability of the toner tends to deteriorate. Therefore, in this respect, the polyester resin preferably has no sulfonic acid group. However, when the polyester resin does not have a sulfonic acid group, especially when the polyester resin is a crystalline resin, the hydrophobicity becomes higher, so the compatibility with the amorphous resin is reduced. . Therefore, conventionally, whether or not to introduce a sulfonic acid group into a polyester resin has advantages and disadvantages in any case.
However, since a compatibility improver is used in the present invention, even if a crystalline polyester resin having no sulfonic acid group having excellent properties for suppressing deterioration of charging property is used, it is compatible with an amorphous resin. Solubility can be secured.

Furthermore, it is more preferable that the polyester resin contains a dicarboxylic acid component having a double bond in addition to the above-mentioned aliphatic dicarboxylic acid and aromatic dicarboxylic acid. A dicarboxylic acid having a double bond can be suitably used to prevent hot offset at the time of fixing in that it can be radically cross-linked through the double bond. Examples of the dicarboxylic acid include, but are not limited to, maleic acid, fumaric acid, 3-hexenedioic acid, and 3-octenedioic acid. In addition, these lower esters, acid anhydrides and the like are also included. Among these, fumaric acid, maleic acid and the like are mentioned in terms of cost.

On the other hand, as the polyhydric alcohol component, a dihydric or higher polyhydric alcohol can be used. Here, as the divalent polyhydric alcohol, polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane, polyoxyethylene (2.2) -2,2-bis (4 -Alkylene (2 to 4 carbon atoms) oxide adduct (average addition mole number 1.5 to 6) of bisphenol A such as hydroxyphenyl) propane, ethylene glycol, propylene glycol, neopentyl glycol, 1,4-butanediol, Examples include 1,3-butanediol and 1,6-hexanediol.
Examples of the trihydric or higher polyhydric alcohol include sorbitol, pentaerythritol, glycerol, and trimethylolpropane.

  When polymerizing an amorphous polyester resin, it is preferable to use a dihydric or higher secondary alcohol and / or a divalent or higher aromatic carboxylic acid compound among the raw material monomers described above. Examples of the dihydric or higher secondary alcohol include propylene oxide adducts of bisphenol A, propylene glycol, 1,3-butanediol, glycerol and the like. Among these, propylene oxide adducts of bisphenol A are preferable and divalent. As the above aromatic carboxylic acid compound, terephthalic acid, isophthalic acid, phthalic acid and trimellitic acid are preferable, and terephthalic acid and trimellitic acid are more preferable.

When the crystalline polyester resin is polymerized, it is preferable to polymerize using an aliphatic dicarboxylic acid and an aliphatic diol. A linear dicarboxylic acid having a main chain portion having 4 to 20 carbon atoms, It is more preferable to use a type aliphatic diol.
When the main chain portion is branched, the crystallinity of the polyester resin is lowered and the melting point is lowered, so that toner blocking resistance, image storage stability, and low-temperature fixability may be deteriorated. Further, when the number of carbon atoms in the main chain portion is less than 4, since the ester bond group concentration is high, the electric resistance is low, and the influence thereof may deteriorate the chargeability of the toner. On the other hand, when the number of carbon atoms in the main chain portion exceeds 20, it may be difficult to obtain a practical material. Therefore, the number of carbon atoms in the main chain portion is more preferably 14 or less.

  Examples of the aliphatic dicarboxylic acid preferably used for the polymerization of the crystalline polyester include succinic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelic acid, sebacic acid, 1,9-nonane. Dicarboxylic acid, 1,10-decanedicarboxylic acid, 1,11-undecanedicarboxylic acid, 1,12-dodecanedicarboxylic acid, 1,13-tridecanedicarboxylic acid, 1,14-tetradecanedicarboxylic acid, 1,16-hexadecanedicarboxylic acid Examples include acids, 1,18-octadecanedicarboxylic acid, and the like, or lower alkyl esters and acid anhydrides thereof. Among these, considering availability, sebacic acid and 1,10-decanedicarboxylic acid are preferable.

Specific examples of the aliphatic diol suitably used for the polymerization of the crystalline polyester include ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6. -Hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, 1,13- Examples include, but are not limited to, tridecanediol, 1,14-tetradecanediol, 1,18-octadecanediol, 1,14-eicosandecanediol, and the like. Among these, 1,8-octanediol, 1,9-nonanediol, and 1,10-decanediol are preferable in view of availability.
Examples of the trivalent or higher alcohol include glycerin, trimethylolethane, trimethylolpropane, pentaerythritol and the like. These may be used individually by 1 type and may use 2 or more types together.

Among the polyvalent carboxylic acid components used for the polymerization of the crystalline polyester resin, the content of the aliphatic dicarboxylic acid is preferably 80 mol% or more, and more preferably 90 mol% or more. When the content of the aliphatic dicarboxylic acid is less than 80 mol%, the crystallinity of the polyester resin is lowered and the melting point is lowered, so that toner blocking resistance, image storage stability, and low-temperature fixability may be deteriorated. .
Moreover, among the polyhydric alcohol components used for the polymerization of the crystalline polyester resin, the content of the aliphatic diol component is preferably 80 mol% or more, and preferably 90 mol% or more. If the content of the aliphatic diol component is less than 80 mol%, the crystallinity of the polyester resin is lowered and the melting point is lowered, so that toner blocking resistance, image storage stability, and low-temperature fixability may be deteriorated. is there.
If necessary, monovalent acids such as acetic acid and benzoic acid and monovalent alcohols such as cyclohexanol benzyl alcohol can also be used for the purpose of adjusting the acid value and hydroxyl value.

The production method of the polyester resin is not particularly limited and can be produced by a general polyester polymerization method in which an acid component and an alcohol component are reacted. Examples thereof include a direct polycondensation method and a transesterification method. Depending on the type, it will be manufactured separately.
The polyester resin can be produced by subjecting the polyhydric alcohol and polyhydric carboxylic acid to a condensation reaction according to a conventional method. For example, the above polyhydric alcohol and polyvalent carboxylic acid, if necessary, a catalyst is added, blended in a reaction vessel equipped with a thermometer, a stirrer, a flow-down condenser, and in the presence of an inert gas (such as nitrogen gas), Heating in the range of 150 ° C or higher and 250 ° C or lower, continuously removing by-product low-molecular compounds from the reaction system, stopping the reaction when it reaches a predetermined acid value, cooling, and the desired reaction It can be manufactured by acquiring an object.
In addition, as a catalyst which can be used at the time of manufacture of a polyester resin, the compatibility improvement agent mentioned above can also be used.

The acid value (mg number of KOH necessary for neutralizing 1 g of resin) of the polyester resin is easy to obtain the above-mentioned molecular weight distribution, and it is easy to prepare a resin particle dispersion by the phase inversion emulsification method. It is preferable that the toner content is in the range of 4 mgKOH / g or more and 30 mgKOH / g or less because the environmental stability of the toner (charging stability when the temperature and humidity change) is easily maintained.
The acid value of the polyester resin can be adjusted by controlling the carboxyl group at the terminal of the polyester resin according to the blending ratio and reaction rate of the starting polyhydric carboxylic acid component and polyhydric alcohol component. Or what has a carboxyl group in the principal chain of a polyester resin is obtained by using trimellitic anhydride as a polyvalent carboxylic acid component.

Further, when a toner is produced by the aggregation and coalescence method using the obtained polyester resin, a resin particle dispersion liquid in which the polyester resin is dispersed in a solution is prepared.
The particle diameter of the resin particle dispersion thus obtained can be measured with a laser diffraction particle size distribution measuring device (LA-700, manufactured by Horiba, Ltd.).

-Colorant-
In general, the toner of the present invention preferably contains a colorant. However, it is not necessary to be visible with the naked eye as in the case of forming an encryption information image such as a barcode, or transparency is required to improve the glossiness of the image. In the required use etc., the colorant may not be contained.

A known colorant can be used as the colorant.
Carbon black, magnetic powder, etc. can be used as the black pigment.
Examples of yellow pigments include Hansa Yellow, Hansa Yellow 10G, Benzidine Yellow G, Benzidine Yellow GR, Slen Yellow, Quinoline Yellow, and Permanent Yellow NCG.

Red pigments include Bengala, Watch Young Red, Permanent Red 4R, Resol Red, Brilliantamine 3B, Brilliantamine 6B, Dupont Oil Red, Pyrazolone Red, Rhodamine B Lake, Lake Red C, Rose Bengal, Eoxin Red, Alizarin Lake Etc.
Blue pigments include bitumen, cobalt blue, alkali blue rake, Victoria blue rake, fast sky blue, indanthrene blue BC, aniline blue, ultramarine blue, calco oil blue, methylene blue chloride, phthalocyanine blue, phthalocyanine green, malachite green oxare. Rate.
Moreover, these can be mixed and used in the state of a solid solution.

These colorants are dispersed by a known method, and for example, a rotary shear type homogenizer, a media type dispersing machine such as a ball mill, a sand mill, or an attritor, a high-pressure opposed collision type dispersing machine, or the like is preferably used.
Further, when the toner is prepared by using the aggregation and coalescence method, these colorants use polar ionic surfactants, and are dispersed in an aqueous solvent using the homogenizer described above. It can be used as a dispersion.
The colorant is selected from the viewpoints of hue angle, saturation, brightness, weather resistance, OHP permeability, and dispersibility in the toner. The content of the colorant contained in the toner is preferably in the range of 4 to 20 parts by mass with respect to 100 parts by mass of the binder resin contained in the toner.

-Release agent-
A release agent may be added to the toner as necessary. When a release agent is used, the release agent is preferably contained in the toner in the range of 3% by mass to 30% by mass, and more preferably in the range of 5% by mass to 15% by mass. If the amount is less than 3% by mass, sufficient fixing stability may not be obtained. If the amount is more than 30% by mass, filming on the surface of the photoconductor tends to occur, and the fixed image may be easily destroyed. is there.

The release agent that can be used is not particularly limited as long as it is a known toner release agent. For example, montan wax, ozokerite, ceresin, paraffin wax, microcrystalline wax, microcrystalline wax, and Fischer-Tropsch wax. Minerals such as petroleum wax, natural gas wax and their modified products, low molecular weight polyolefins such as polyethylene, polypropylene and polybutene, silicones which show a softening point upon heating, oleic amide, erucic amide, ricinoleic acid Examples thereof include fatty acid amides such as amide and stearamide, carnauba wax, rice wax, candelilla wax, plant waxes such as tree wax and jojoba oil, and beeswax animal waxes.
In addition, as a modifying aid component of the release agent, a higher alcohol having 10 to 18 carbon atoms or a mixture thereof, and a higher fatty acid monoglyceride having 16 to 22 carbon atoms or a mixture thereof may be used in combination.

-Other additives-
In addition to the above-listed components, various additives can be internally or externally added to the toner as required. Examples of the additive include a charge control agent, a fluidity aid, and a cleaning aid.
For example, examples of the charge control agent include silica, alumina, titania, calcium carbonate, magnesium carbonate, tricalcium phosphate, and all inorganic particles usually used as an external additive on the toner surface. These inorganic particles can be externally added to the toner in a wet manner. In this case, these inorganic particles can be used by being dispersed in a solvent using an ionic surfactant, a polymer acid, a polymer base, or the like.
In addition, when a charge control agent is internally added using the aggregation and coalescence method described later, as the charge control agent, a quaternary ammonium salt compound, a nigrosine compound, a dye comprising a complex such as aluminum, iron, or chromium, Various commonly used charge control agents such as triphenylmethane pigments can be used. However, in the aggregation coalescence method, it is used for internal addition in the process of aggregating the toner raw materials and fusing the aggregated aggregated particles from the viewpoint of controlling the ionic strength that affects the stability of the aggregated particles and reducing wastewater contamination. As the charge control agent, a material that is difficult to dissolve in water is suitable.

  In addition, for the purpose of imparting fluidity and improving cleaning properties, inorganic particles such as silica, alumina, titania and calcium carbonate and resin particles such as vinyl resin, polyester and silicone are used as fluidity aids and cleaning aids. It can be externally added to the surface. These external additives can be added to the toner particle surfaces while shearing the dry toner particles.

Examples of inorganic oxide particles added to the toner include SiO ₂ , TiO ₂ , Al ₂ O ₃ , CuO, ZnO, SnO ₂ , CeO ₂ , Fe ₂ O ₃ , MgO, BaO, CaO, K ₂ O, and Na _2. O, ZrO ₂ , CaO · SiO ₂ , K ₂ O · (TiO ₂ ) n (where n is an integer of 1 or more), Al ₂ O ₃ · 2SiO ₂ , CaCO ₃ , MgCO ₃ , BaSO ₄ , MgSO _4, etc. It can be illustrated. Of these, silica particles and titania particles are particularly preferable.
It is desirable that the surface of these inorganic oxide particles is previously hydrophobized. This hydrophobizing treatment can improve the powder fluidity of the toner, as well as the effect of charging on the environment and resistance to carrier contamination.

  The hydrophobic treatment can be performed by immersing the inorganic oxide particles in the hydrophobic treatment agent. Although there is no restriction | limiting in particular as a hydrophobization processing agent, For example, a silane coupling agent, a silicone oil, a titanate coupling agent, an aluminum coupling agent etc. are mentioned. These may be used individually by 1 type and may use 2 or more types together. Among these, silane coupling agents are preferable.

As the silane coupling agent, for example, any type of chlorosilane, alkoxysilane, silazane, and a special silylating agent can be used. Specifically, methyltrichlorosilane, dimethyldichlorosilane, trimethylchlorosilane, phenyltrichlorosilane, diphenyldichlorosilane, tetramethoxysilane, methyltrimethoxysilane, dimethyldimethoxysilane, phenyltrimethoxysilane, diphenyldimethoxysilane, tetraethoxysilane, Methyltriethoxysilane, dimethyldiethoxysilane, phenyltriethoxysilane, diphenyldiethoxysilane, isobutyltriethoxysilane, decyltrimethoxysilane, hexamethyldisilazane, N, O- (bistrimethylsilyl) acetamide, N, N- ( Trimethylsilyl) urea, tert-butyldimethylchlorosilane, vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane , Γ-methacryloxypropyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, γ-mercapto Examples thereof include propyltrimethoxysilane and γ-chloropropyltrimethoxysilane.
The amount of the hydrophobizing agent varies depending on the kind of the inorganic oxide particles and cannot be defined unconditionally. Degree.

-Various properties of toner-
The volume average particle diameter of the toner is preferably 3 μm or more and 9 μm or less, and more preferably 3 μm or more and 8 μm or less. If the volume average particle size is less than 3 μm, the chargeability may be insufficient and the developability may be deteriorated, and if it exceeds 9 μm, the resolution of the image may be deteriorated.
Further, the volume average particle size distribution index GSDv of the toner is preferably 1.30 or less.
When the volume distribution index GSDv exceeds 1.30, the resolution of the image may deteriorate.

In the present invention, the volume average particle size of the toner and the value of the volume average particle size distribution index GSDv are measured and calculated as follows.
First, with respect to the divided particle size range (channel), the volume-based particle size distribution of the toner measured using a Coulter Multimizer-II (manufactured by Beckman-Coulter) is accumulated from the small diameter side with respect to the divided particle size range (channel). A distribution is drawn, and the particle size that becomes 16% cumulative is defined as the cumulative volume average particle size D16v, and the particle size that becomes 50% cumulative is defined as the cumulative volume average particle size D50v. Similarly, the particle diameter that is 84% cumulative is defined as the cumulative volume average particle diameter D84v.
At this time, the volume average particle diameter means the cumulative volume average particle diameter D50v, and the volume average particle size distribution index (GSDv) is defined as (D84v / D16v) ^0.5 .
In the measurement, 0.5 mg to 50 mg of a measurement sample is added to 2 ml of a 5% by mass aqueous solution of sodium alkylbenzenesulfonate as a dispersant. This is added to 100 ml to 150 ml of the electrolytic solution.
The electrolyte solution in which the sample is suspended is subjected to a dispersion treatment with an ultrasonic disperser for 1 minute, and the particle size distribution of particles having a diameter in the range of 2 μm to 60 μm by using the Coulter counter TA-II with an aperture diameter of 100 μm. Measure. The number of particles to be sampled is 50,000.

The toner shape factor SF1 is preferably in the range of 110 to 160, and preferably in the range of 125 to 140.
When the shape factor SF1 is less than 110, a residual toner is generally generated in the transfer process during image formation. Therefore, it is necessary to remove the residual toner. However, the cleaning performance when the residual toner is cleaned with a blade or the like is required. It is easy to damage and may result in image defects. On the other hand, when the shape factor SF1 exceeds 160, when the toner is used as a developer, the toner may be destroyed due to a collision with a carrier in the developing device. At this time, as a result, the fine powder increases or the release agent component exposed on the toner surface may contaminate the surface of the photoreceptor to impair the charging characteristics. May cause problems.

The shape factor SF1 means a value defined by the following formula (1).
Formula (1) SF1 = ((absolute maximum length of toner particles) ² / projection area of toner particles) × (π / 4) × 100
In the present invention, the absolute maximum length of the toner particles represented by the formula (1) and the projected area of the toner particles are photographed with an optical microscope (Nikon, Microphoto-FXA) enlarged at a magnification of 500 times. The obtained image information was obtained by introducing the image information into an image analysis apparatus (Luzex III) manufactured by Nireco Co., Ltd. via an interface and performing image analysis.
The value of the shape factor SF1 was calculated as an average value based on data obtained by measuring 1000 toner particles sampled randomly.

Further, it is desirable that the crystalline resin is not exposed as much as possible on the surface of the toner, and the state of exposure of the crystalline resin on the toner surface can be confirmed using a transmission electron microscope (TEM) as follows.
First, the toner particles are embedded using a bisphenol A type liquid epoxy resin and a curing agent, and then a cutting sample is prepared. Next, the cutting sample is cut at −100 ° C. using a cutting machine using a diamond knife, for example, LEICA ultramicrotome (manufactured by Hitachi Technologies) to prepare an observation sample. Further, this observation sample is left in a desiccator under a ruthenium tetroxide atmosphere for dyeing. Judgment of dyeing can be judged by the degree of dyeing of the tape left at the same time. The observation sample dyed in this way can be observed with a TEM at a magnification of about 5000 times.
Since the toner sample is dyed with ruthenium tetroxide, the non-crystalline resin, the crystalline resin, and, if necessary, the release agent contained in the toner can be discriminated as the difference in dyeing density. Therefore, it is possible to determine whether or not the crystalline resin is exposed on the toner surface and the degree of exposure.
However, since the release agent has a structurally long carbon chain part, when the toner contains the release agent, the crystalline resin and the release agent are completely compatible, and the two cannot be discriminated separately. There is. In this case, it is determined that a compatible solution of the crystalline resin and the release agent has been formed, and the degree to which the crystalline resin is exposed on the toner surface is determined based on how the compatible solution is exposed to the toner surface. be able to.

Here, in the toner of the present invention, the exposure rate of the crystalline resin specified by the following formula (however, when the above-mentioned compatible solution is formed, it means the average value of the exposure rate of the compatible solution) is 10 % Or less, preferably 3% or less, and the closer to 0%, the better.
Exposure rate = total length of exposed area ÷ total length of toner cross section outer circumference x 100 (%)
[In the above formula, the total length of the exposed portion means the total value of the length of the exposed portion in the section of 10 toner particles randomly sampled, and the total length of the outer periphery of the toner cross section represents the total length of the exposed portion. It means the total value of the outer peripheral lengths of the 10 toner particle cross sections used in the measurement. ]

  In order to ensure the exposure rate of 10% or less, the toner of the present invention includes a core layer containing at least a crystalline resin, a shell layer covering the core layer, and containing an amorphous resin. Particularly preferred is a toner having a core-shell structure. This is because the shell layer is formed so that the exposure of the crystalline resin contained in the core layer is suppressed.

-Toner production method-
Next, a toner manufacturing method will be described. In the production of the toner, any known production method such as a dry production method such as a kneading and pulverization method or a wet production method such as an agglomeration coalescence method can be used.
In any case, the crystalline resin, the amorphous resin and the compatibility improver are mixed (for example, forced mixing using mechanical force such as shear force, It is particularly preferable that the heat treatment is performed at a temperature higher than the higher of the melting point of the crystalline resin or the glass transition temperature of the non-crystalline resin in a state of being spontaneously mixed by aggregation using the cohesive force of the components. This is because the compatibility improver can thermally diffuse into these two types of resins to further improve the compatibility between the crystalline resin and the amorphous resin.

  The compatibility improver can be added at any timing in the process of preparing the toner including the production stage of the toner raw material. However, before mixing the crystalline resin and the amorphous resin as described above, The resin is preferably dispersed and contained in the resin. Further, from the viewpoint of dispersing the compatibility improver more uniformly in the resin, the toner is preferably prepared by a wet process rather than a dry process, and among the wet processes, the toner structure, particle size / particle size distribution, toner It is more preferable to use an agglomeration and coalescence method that makes it easier to control the various physical properties.

In the following, a more detailed description will be given on the assumption that the aggregation and coalescence method is used as a preferred toner production method, but the toner production method of the present invention is not limited to the aggregation and coalescence method.
However, the agglomeration and coalescence method involves agglomeration including fine particles made of crystalline resin (volume average diameter: 10 to 300 nm) and fine particles made of amorphous resin, as well as other component fine particles used as necessary. And forming aggregated particles. For this reason, by passing through the formation process (mixing stage) of the aggregated particles, the crystalline resin and the amorphous resin can be roughly dispersed in the aggregated particles. Furthermore, it is also possible to dispose the crystalline resin component relatively inside the agglomerated particles by further attaching and covering the surface of the agglomerated particles with non-crystalline resin fine particles. From these viewpoints, the aggregation and coalescence method is preferable as the method for producing the toner of the present invention.
In this case, the toner of the present invention is a raw material dispersion obtained by mixing at least a resin particle dispersion in which particles made of crystalline resin are dispersed and a resin particle dispersion in which particles made of an amorphous resin are dispersed. It can be produced through at least the aggregation step for forming the aggregated particles and the fusion step for fusing the aggregated particles by heating.
The preparation of the raw material dispersion usually preferably includes a colorant particle dispersion in which colorant particles are dispersed and a release agent particle dispersion in which a release agent is dispersed. A dispersion in which other components are dispersed may be used as necessary.

In this toner manufacturing process, as a method of adding the compatibility improver to the toner, a method of dispersing in a crystalline resin or an amorphous resin in advance (first addition method), or a raw material used in the aggregation step A method of adding to the dispersion (second addition method) can be used, and both methods can be used in combination.
When at least the crystalline resin particles and the amorphous resin particles described above are used, the affinity between the crystalline resin and the amorphous resin is poor. Instead of being mixed together, they tend to be more separated and united with the same type of resin. For this reason, coalescence does not proceed at the interface between two types of resin particles having different hydrophobicity / hydrophilicity constituting the aggregated particles, and the resin composition is unevenly distributed and tends to be non-uniform after fusion. Further, this tendency is caused when the melt viscosity of the two types of resins used in the aggregation process are greatly different from each other (specifically, the relative ratio of the viscosity of the crystalline resin and the amorphous resin at 90 ° C. is When the viscosity of the resin is the standard (100%), the viscosity of the other resin is 500% or more, or when the volume ratio between the two types of resins used for toner preparation is close (specifically, crystalline resin) : Non-crystalline resin = in the range of 30:70 to 70:30).
However, by using the first addition method and the second addition method, particularly the first addition method, it is only necessary to suppress the promotion of phase separation between the crystalline resin and the amorphous resin in the fusion process described above. Furthermore, the compatibility between the crystalline resin and the amorphous resin can be improved.

After passing through the aggregation step, a resin particle dispersion in which particles made of an amorphous resin are dispersed is added to the raw material dispersion in which the aggregated particles before forming the fusion step are formed. As the particles, an attachment step of attaching the amorphous resin particles to the core particles may be performed (hereinafter, the aggregation step is the first aggregation step, the attachment step is the second aggregation step, and the first aggregation step). The non-crystalline resin used may be referred to as a first non-crystalline resin, and the non-crystalline resin used in the second aggregation step may be referred to as a second non-crystalline resin).
In this case, a toner having a so-called core-shell structure having a core layer containing at least a crystalline resin and an amorphous resin and a shell layer containing an amorphous resin covering the core layer can be obtained.

The heating temperature in the fusion step can be set to be equal to or higher than the glass transition temperature of the (first) non-crystalline resin when the second aggregation step is not performed, and the second aggregation step is performed. Can be set to a glass transition temperature higher than any one of the glass transition temperatures of the first amorphous resin and the second amorphous resin.
When the second aggregation step is performed, the method for adding the compatibility improver to the toner is selected from a crystalline resin, a first amorphous resin, and a second amorphous resin in advance. At least one of the method of dispersing in at least one of the resins, the method of adding to the raw material dispersion used in the first aggregation step, and the method of adding to the raw material dispersion used in the second aggregation step Either one can be used, and two or more types may be used in combination.

Next, each step will be described in more detail.
In the first aggregating step, first, a resin particle dispersion in which particles made of a crystalline resin are dispersed, a resin particle dispersion in which particles made of an amorphous resin are dispersed, and a colorant as necessary Prepare a particle dispersion or release agent particle dispersion.
The resin particle dispersion can be prepared by, for example, phase inversion emulsification by dissolving the resin in a solvent that can dissolve the resin. In addition, the colorant particle dispersion liquid uses, for example, an ionic surfactant and an opposite polarity ionic surfactant to disperse colorant particles of a desired color such as black, blue, red, and yellow in a solvent. Can be adjusted.
In addition, the release agent particle dispersion includes, for example, a release agent dispersed in water together with a polymer electrolyte such as an ionic surfactant, a polymer acid, or a polymer base, and heated to a temperature higher than the melting point and subjected to strong shearing. It can be adjusted by granulating with a device to be applied.
As a device for dispersing each component in the solution by the above mechanical means, Manton Gorin high-pressure homogenizer (Gorin), continuous ultrasonic homogenizer (Nippon Seiki Co., Ltd.), Nanomizer (Nanomizer), Microfluidizer Examples include Dizer (Mizuho Industrial Co., Ltd.), Harel type homogenizer, Slasher (Mitsui Mining Co., Ltd.), Cavitron (Eurotech Co., Ltd.), and the like.

  Next, various dispersions such as a crystalline resin particle dispersion and an amorphous resin particle dispersion are mixed to heteroaggregate toner raw material components such as crystalline resin particles and (first) amorphous resin particles. Aggregated particles (core particles) having a diameter substantially close to the desired toner diameter are formed.

  Subsequently, an adhesion process is performed as necessary. In this case, a resin particle dispersion containing the second amorphous resin particles is added to the raw material dispersion on the surface of the core particles obtained in the first aggregation step, and the second amorphous resin particles are The agglomerated particles (core / shell structure) having a core / shell structure in which a coating layer made of the second non-crystalline resin particles is formed on the surface of the core particles by adhering and forming a coating layer having a desired thickness on the surface of the core particles. Shell agglomerated particles). The second amorphous resin particles used at this time may be the same as or different from the amorphous resin particles used in the first aggregation step.

  In addition, the crystalline resin particles used in the first aggregation process and the second aggregation process, the first non-crystalline resin particles, the second non-crystalline resin particles, and other used as necessary The particle diameter of the colorant particles and the release agent particles contained in the dispersion is 1 μm or less in order to easily adjust the volume average particle diameter and particle size distribution of the toner to desired values. Is preferable, and it is more preferably within a range of 100 nm or more and 300 nm or less.

  In the first aggregating step, when the colorant particle dispersion is used for adjusting the raw material dispersion, the amount of the two polar ionic surfactants (dispersants) contained in the colorant particle dispersion is The balance can be shifted in advance. For example, an inorganic metal salt such as calcium nitrate or a polymer of an inorganic metal salt such as polyaluminum chloride is ionically neutralized, and the melting point of the crystalline resin particles, (first) amorphous resin Aggregated particles (core particles) can be produced by heating at a temperature lower than the glass transition temperature of the particles.

  In this case, in the second agglomeration step, the second resin particle dispersion treated with the dispersant having the polarity and amount that compensates for the deviation in the balance between the two polar dispersants described above is used as the solution containing the core particles. The core / shell aggregated particles can be prepared by adding a small amount of the core particles or the second amorphous resin particles used in the second aggregating step, if necessary, slightly below the glass transition temperature. it can. In addition, the 1st and 2nd aggregation process may be repeatedly performed in multiple steps stepwise.

  Next, in the fusion step, the aggregated particles obtained through the first aggregation step or the core / shell aggregated particles obtained through the first and second aggregation steps are heated in a solution to fuse. Get particles. The heating temperature in this case can be set to be equal to or higher than the glass transition temperature of the first amorphous resin in the case of the agglomerated particles obtained through the first agglomeration step, and can be obtained through the first and second agglomeration steps. In the case of the formed core / shell aggregated particles, the glass transition temperature of the first amorphous resin and the glass transition temperature of the second amorphous resin are set to be higher than the glass transition temperature showing a higher temperature. it can.

After completion of the fusing process, the fused particles formed in the solution are subjected to a known washing process, solid-liquid separation process, and drying process to obtain dried particles (toner particles).
In addition, it is preferable that the washing | cleaning process performs substitution washing | cleaning by ion-exchange water fully from a charging point. The solid-liquid separation step is not particularly limited, but suction filtration, pressure filtration, and the like are preferably used from the viewpoint of productivity. Further, although the drying process is not particularly limited, freeze drying, flash jet drying, fluidized drying, vibration fluidized drying and the like are preferably used from the viewpoint of productivity.

The resin particle dispersion used when the toner is produced by the aggregation coalescence method is prepared by adjusting the acid value of the resin, emulsifying and dispersing using an ionic surfactant, or using a phase inversion emulsification method. If the resin is soluble in an oily solvent with a relatively low solubility in water, the resin is dissolved in those solvents and dissolved in water with a disperser such as a homogenizer together with an ionic surfactant or polymer electrolyte. The particles can be dispersed in the mixture and then heated or reduced in pressure to evaporate the solvent.
Among these methods, a phase inversion emulsification method that can narrow the particle size distribution of the resin particles dispersed in the dispersion and can be easily prepared in a volume average particle size range of 0.08 nm to 0.40 nm is effective.

In the phase inversion emulsification method, first, an oil phase is prepared by dissolving a resin in an organic solvent that dissolves the resin, an amphiphilic organic solvent alone, or a mixed solvent. Next, a small amount of a basic compound is dropped while stirring the oil phase, and water is added dropwise little by little while stirring. Thereby, water droplets are taken into the oil phase. Thereafter, when the amount of water dropped exceeds a certain amount, the state in which the water phase is present as droplets in the oil phase is reversed, and the oil phase is present in the water phase as oil droplets. Thereafter, the organic solvent is volatilized under reduced pressure to obtain a resin particle dispersion.

  Here, the amphiphilic organic solvent means a solvent having a solubility in water at 20 ° C. of at least 5 g / L or more, preferably 10 g / L or more. When the solubility is less than 5 g / L, the effect of accelerating the aqueous treatment rate is poor, and the storage stability of the resulting resin particle dispersion may be inferior.

  Examples of organic solvents that can be used for phase inversion emulsification include, for example, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, sec-butanol, tert-butanol, n-amyl alcohol, isoamyl alcohol, and sec-amyl alcohol. , Tert-amyl alcohol, 1-ethyl-1-propanol, 2-methyl-1-butanol, n-hexanol, cyclohexanol and other alcohols, methyl ethyl ketone, methyl isobutyl ketone, ethyl butyl ketone, cyclohexanone, isophorone and other ketones , Ethers such as tetrahydrofuran and dioxane, ethyl acetate, acetic acid-n-propyl, isopropyl acetate, acetic acid-n-butyl, isobutyl acetate, acetic acid-sec-butyl, acetic acid-3-methoxybutyl Esters such as methyl propionate, ethyl propionate, diethyl carbonate, dimethyl carbonate, ethylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, ethylene glycol ethyl ether acetate, diethylene glycol , Diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether, diethylene glycol ethyl ether acetate, propylene glycol, propylene glycol monomethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl Glycol derivatives such as ether, propylene glycol methyl ether acetate, dipropylene glycol monobutyl ether, 3-methoxy-3-methylbutanol, 3-methoxybutanol, acetonitrile, dimethylformamide, dimethylacetamide, diacetone alcohol, ethyl acetoacetate Etc. can be illustrated. These solvents can be used singly or in combination of two or more.

  Moreover, as a basic compound, ammonia, the organic amine compound whose boiling point is 250 degrees C or less, etc. are mentioned, for example. Examples of desirable organic amine compounds include triethylamine, N, N-diethylethanolamine, N, N-dimethylethanolamine, aminoethanolamine, N-methyl-N, N-diethanolamine, isopropylamine, iminobispropylamine, ethylamine , Diethylamine, 3-ethoxypropylamine, 3-diethylaminopropylamine, sec-butylamine, propylamine, methylaminopropylamine, dimethylaminopropylamine, methyliminobispropylamine, 3-methoxypropylamine, monoethanolamine, diethanolamine, Triethanolamine, morpholine, N-methylmorpholine, N-ethylmorpholine and the like can be mentioned.

The basic compound is contained in the polyester resin in an amount that can be at least partially neutralized according to the carboxyl group contained in the polyester resin when a polyester resin is used as the resin component for preparing the resin particle dispersion. It is preferable to add in the range of 0.2 times equivalent to 9.0 times equivalent to the carboxyl group, and more preferably in the range of 0.6 times equivalent to 2.0 times equivalent.
If the amount is less than 0.2 times equivalent, the effect of adding a basic compound may not be exhibited. If the amount exceeds 9.0 times equivalent, it is estimated that the hydrophilicity of the oil phase increases excessively. The diameter distribution becomes broad and a good resin particle dispersion cannot be obtained.

  In addition, when preparing a toner by the aggregation coalescence method, emulsion polymerization, dispersion of resin particles, dispersion of colorant particles such as pigment, dispersion of a release agent, aggregation of toner raw material components, or emulsion polymerization and various components Examples of surfactants used for dispersion of particles and stabilization of aggregated particles include sulfate anion surfactants, sulfonates, phosphates, soaps, and the like, amine salts, quaternary ammonium Cationic surfactants such as salt types can be used, and it is also effective to use nonionic surfactants such as polyethylene glycol, alkylphenol ethylene oxide adducts, and polyhydric alcohols in combination with these surfactants Is. As a means for dispersing the surfactant in the solution, a general means such as a rotary shear type homogenizer, a ball mill having a media, a sand mill, or a dyno mill can be used.

<Electrostatic image developer>
The electrostatic image developer of the present invention (hereinafter sometimes referred to as “developer”) is not particularly limited as long as it contains the toner of the present invention. It is preferably either a developer or a two-component developer containing a toner and a carrier.
The carrier used for the two-component developer is not particularly defined, and a known carrier can be used.
Examples of the carrier core material include magnetic metals such as iron, steel, nickel, and cobalt, alloys of these magnetic metals with manganese, chromium, rare earth, and magnetic oxides such as ferrite and magnetite. However, from the viewpoint of core material surface properties and core material resistance, ferrite is preferable, and ferrite containing manganese, lithium, strontium, magnesium and the like is particularly preferable.

The carrier preferably has a core surface coated with a resin. There is no restriction | limiting in particular as resin which coat | covers a core material, According to the objective, it can select.
Examples of resins that can be used for coating the core material include polyolefin resins such as polyethylene and polypropylene; polystyrene, acrylic resin, polyacrylonitrile, polyvinyl acetate, polyvinyl alcohol, polyvinyl butyral, polyvinyl chloride, polyvinyl carbazole, polyvinyl ether, and polyvinyl. Polyvinyl resins such as ketones and polyvinylidene resins; vinyl chloride-vinyl acetate copolymers; styrene-acrylic acid copolymers; straight silicone resins composed of organosiloxane bonds or modified products thereof; polytetrafluoroethylene, polyvinyl fluoride , Fluororesins such as polyvinylidene fluoride and polychlorotrifluoroethylene; silicone resins; polyesters; polyurethanes; polycarbonates; - formaldehyde resins, melamine resins, benzoguanamine resins, urea resins, amino resins such as polyamide resins, epoxy resins, per se known resins and the like.
These resins may be used alone or in combination of two or more. Of the resins listed above, it is preferable to use at least a fluorine-based resin and / or a silicone resin. When at least a fluorine-based resin and / or a silicone resin is used as the resin, the effect of preventing carrier contamination (impact) due to toner or external additives can be enhanced.

It is preferable that resin particles and / or conductive particles are dispersed and contained in the resin film covering the core material. Examples of the resin particles include thermoplastic resin particles and thermosetting resin particles. Among these, a thermosetting resin is preferable from the viewpoint of relatively easily increasing the hardness, and resin particles using a resin containing nitrogen are preferable from the viewpoint of imparting negative chargeability to the toner. In addition, these resin particles may be used individually by 1 type, and may use 2 or more types together.
The average particle size of the resin particles is preferably about 0.1 μm to 2 μm, and is in the range of 0.2 μm to 1 μm. If the average particle size of the resin particles is less than 0.1 μm, the dispersibility of the resin particles in the resin coating may be deteriorated. May not be possible.

  As conductive particles, metal particles such as gold, silver and copper, carbon black particles, semiconductive oxide particles such as titanium oxide and zinc oxide, titanium oxide, zinc oxide, barium sulfate, aluminum borate, potassium titanate Examples thereof include particles whose surface such as powder is covered with tin oxide, carbon black, metal, and the like. These may be used individually by 1 type and may use 2 or more types together. Among these, carbon black particles are preferable from the viewpoints of production stability, cost, conductivity, and the like. The type of carbon black is not particularly limited, but carbon black having a DBP oil absorption of about 50 ml / 100 g to 250 ml / 100 g is preferable because of excellent production stability.

The method for forming the resin film on the surface of the core material is not particularly limited. For example, resin particles such as crosslinkable resin particles and / or conductive particles, and resins such as styrene acrylic resin, fluorine resin, and silicone resin Examples thereof include a method using a resin film forming solution containing a resin for forming a film in a solvent.
Specifically, a dipping method in which the core material is immersed in a resin film forming solution, a spray method in which the resin film forming solution is sprayed on the surface of the core material, and a resin film forming method in a state where the core material is suspended by flowing air. Examples include a kneader coater method in which a solution is mixed and a solvent is removed. Among these, a kneader coater method is preferable.

The solvent used for the resin film forming solution is not particularly limited as long as it can dissolve only the resin for forming the resin film, and can be selected from among solvents known per se, for example, And aromatic hydrocarbons such as toluene and xylene, ketones such as acetone and methyl ethyl ketone, ethers such as tetrahydrofuran and dioxane, and the like.
When resin particles are dispersed in the resin film, the resin particles are uniformly dispersed in the resin film in the thickness direction and in the tangential direction of the carrier surface. Even in this case, it is possible to always maintain the same surface state as that immediately after the manufacture of the carrier, and to maintain a good charge imparting ability for the toner over a long period of time.

When conductive particles are dispersed in the resin coating, the conductive coating is uniformly distributed in the thickness direction and the tangential direction of the carrier surface. However, it is possible to always maintain the same surface state as that immediately after the manufacture of the carrier, and to prevent the deterioration of the carrier for a long period of time.
Even when the resin particles and the conductive particles are dispersed in the resin coating, the above-described effects can be achieved at the same time.

<Image Forming Method, Image Forming Apparatus, Toner Cartridge, and Process Cartridge>
Next, an image forming method using the developer of the present invention will be described.
As a method for forming an image using the toner of the present invention, a known electrophotographic method can be used. Specifically, an electrostatic latent image forming step for forming an electrostatic latent image on the surface of an image carrier, and a toner A toner image forming step of developing the electrostatic latent image with a developer containing the toner, forming a toner image, a transfer step of transferring the toner image to a recording medium, and a fixing step of fixing the toner image to the recording medium It is preferable that it contains.
In addition to these processes, a known process used in an electrophotographic image forming method can be combined. For example, a cleaning process for cleaning toner remaining on the surface of the image carrier after the transfer process is completed. It may also contain or the like.
In the image forming method of the present invention, since the toner of the present invention is used, an image is formed immediately after the charging process is performed (completely stopped state) immediately after being left for several hours to more than ten hours (specifically, completely Even if an image is formed within 2 seconds to 10 seconds after the developing machine is operated from the stopped state, the occurrence of fog due to insufficient charge amount of toner is suppressed, and an image of good quality from the initial stage of image formation. Can be obtained.

  Here, the electrostatic latent image forming step is a step of forming an electrostatic latent image by charging the surface of the image carrier with a charging means and then exposing the image carrier with a laser optical system or an LED array. is there. Examples of the charging unit include a non-contact type charger such as corotron and scorotron, and a contact type that charges the image carrier surface by applying a voltage to a conductive member that is in contact with the image carrier surface. Any type of charger may be used. However, a contact charging type charger is preferable from the viewpoint that the amount of ozone generated is small, environmentally friendly, and excellent printing durability. In the contact charging type charger, the shape of the conductive member may be any of a brush shape, a blade shape, a pin electrode shape, a roller shape, and the like, and is not limited. Note that the latent image forming step is not limited to the above-described embodiment.

  In the toner image forming step, a developer holding body on which a developer layer containing at least toner is formed is brought into contact with or brought close to the surface of the image holding body, and the electrostatic latent image on the surface of the image holding body is subjected to toner. In which a toner image is formed on the surface of the image carrier. The development method can be performed using a known method, and examples of the development method when the developer is a two-component developer include a cascade method and a magnetic brush method. The developing method is not limited to the above-described mode.

  The transfer step is a step of transferring a toner image formed on the surface of the image carrier to a recording medium. The transfer process may be a system in which a toner image is directly transferred onto a recording medium such as paper, or a system in which the toner image is transferred onto a recording medium such as paper after being transferred onto a drum-like or belt-like intermediate transfer member. The transfer method is not limited to the above-described mode.

  For example, a corotron can be used as a transfer device that transfers the toner image from the image carrier to paper or the like. The corotron is effective as a means for charging the paper, but in order to give a predetermined charge to the paper as a recording medium, a high voltage of several kV must be applied and a high voltage power source is required. In addition, ozone is generated by corona discharge, which causes deterioration of rubber parts and the image carrier. Therefore, contact transfer that transfers a toner image onto a sheet by pressing a conductive transfer roll having an elastic material against the image carrier. The method is preferred. The transfer device is not limited to the above-described embodiment.

  The cleaning step is a step of removing toner, paper dust, dust, etc. adhering to the surface of the image carrier by bringing a blade, a brush, a roll or the like into direct contact with the surface of the image carrier.

  The most commonly employed method is a blade cleaning method in which a rubber blade such as polyurethane is pressed against the image carrier. On the other hand, a magnetic brush method in which a magnet is fixedly arranged inside, a cylindrical non-magnetic sleeve that can rotate on the outer periphery thereof, a magnetic carrier is held on the sleeve surface, and toner is collected, A method may be used in which semiconductive resin fibers and animal hairs are rotatable in a roll shape, and a toner having a polarity opposite to that of the toner is applied to the roll to remove the toner. In the former magnetic brush system, a cleaning pretreatment corotron may be provided. The cleaning method is not limited to the above-described mode.

  The fixing step is a step of fixing the toner image transferred on the surface of the recording medium with a fixing device. As the fixing device, a heat fixing device using a heat roll is preferably used. The heat fixing device includes a fixing roller having a heater lamp for heating inside a cylindrical metal core, a so-called release layer formed on the outer peripheral surface by a heat resistant resin film layer or a heat resistant rubber film layer, and the fixing roller. The pressure roller or the pressure belt is arranged in pressure contact with the roller and has a layer containing a heat-resistant elastic material formed on the outer peripheral surface of the cylindrical metal core or the surface of the belt-like base material. In the toner image fixing process, a recording medium on which a toner image is formed is passed through a contact portion formed by a fixing roller and a pressure roller or a pressure belt, and heat of binder resin, additives, etc. in the toner is passed. Fix by melting. As a fixing member constituting the fixing device, a roll-shaped member or an endless belt-shaped member containing a low surface energy material typified by a fluororesin component and a silicone-based resin on the surface can be used. However, the fixing method is not limited to the above-described mode.

In the case of producing a full-color image, each of the plurality of image holding bodies has a developer holding body for each color, and a latent image forming step using each of the plurality of image holding bodies and the developer holding bodies, and a toner image Through a series of steps including a forming step, a transfer step, and a cleaning step, each color toner image for each step is sequentially stacked on the same recording medium surface, and the stacked full-color toner images are thermally fixed in the fixing step. An image forming method is preferably used.
By using the developer of this embodiment in the image forming method, stable development, transfer, and fixing performance can be obtained even in a tandem system that is suitable for, for example, small size and high-speed color.

The configuration of the image forming apparatus that performs the above-described image forming method is not particularly limited, but the image carrier, a charging unit that charges the surface of the image carrier, and the charged image. An electrostatic latent image forming means for forming an electrostatic latent image on the surface of the holding body; a toner image forming means for developing the electrostatic latent image with the developer to form a toner image; and the toner image on the surface of the recording medium. The image forming apparatus preferably includes at least a transfer unit that transfers the toner image to the surface of the recording medium and a fixing unit that fixes the toner image transferred to the surface of the recording medium.
In this case, it is preferable to further include other known means such as a cleaning means for cleaning the toner remaining on the surface of the image carrier after the toner image is transferred.

In the image forming apparatus having the above-described configuration, a toner cartridge that is detachable from the image forming apparatus and contains a developer to be supplied to the toner image forming unit may be used. Further, the image forming apparatus is detachable from the image forming apparatus, accommodates the image carrier and the developer, and supplies the developer to the electrostatic latent image formed on the surface of the image carrier to form a toner image. A process cartridge including at least a toner image forming unit may be used.
As described above, the process cartridge is a single unit that is detachable from the apparatus main body including at least the image holding member and the toner image forming unit. In addition, the process cartridge includes a charging unit, an exposure unit, and a cleaning unit. It may be.

  Examples of recording media for transferring toner images include plain paper used in electrophotographic copying machines, printers, OHP sheets, coated paper whose surface is coated with resin, art paper for printing, etc. Can be used.

In addition, since a toner containing a crystalline resin and an amorphous resin that has been used conventionally has a crystalline resin and can be fixed in a low temperature range, basically, the image forming apparatus is warmed up. Time can also be shortened. However, if the compatibility between the crystalline resin and the non-crystalline resin contained in the toner is low, as described above, the charge amount becomes remarkably when left for several hours to more than ten hours after the charging process. descend.
In this case, for example, in an office, the image forming apparatus is turned on first in the morning, and the time until the fixing device reaches a fixing temperature from the completely stopped state where the apparatus is completely stopped overnight (that is, warm Even if the toner in the developing device is agitated for a time equivalent to the up type), the charge amount of the toner is not sufficiently recovered. If an image is formed immediately after the warm-up type in this state, fog or the like may occur. It is also expected to occur.

  In particular, in order to cope with further energy savings in the future, in image forming apparatuses that support fixing at lower temperatures, there is a potential for shortening the warm-up type determined by the time required for heating the fixing machine. In order to prevent the occurrence of fogging due to insufficient charge amount of the toner, the warm-up state is maintained until the charge amount of the toner recovers to the extent that fogging does not occur after the fixing machine is heated. There is a possibility that a problem arises that the warm-up type cannot be shortened substantially.

However, the toner of the present invention is extremely easy to avoid the above-mentioned problems because the decrease in the charge amount is suppressed even if the toner is left for several hours to more than ten hours after the charging process. From this point of view, it is preferable that the toner of the present invention can be fixed at a lower temperature. Specifically, the toner of the present invention preferably has a glass transition temperature of 63 ° C. or less, and 58 More preferably, it is not higher than ° C. The lower limit of the glass transition temperature of the toner is not particularly limited, but is preferably 50 ° C. or higher from the viewpoint of toner storage stability and blocking prevention.
The glass transition temperature of the toner was determined by measuring using a differential scanning calorimeter (manufactured by Shimadzu Corporation: DSC-50) under a temperature rising rate of 3 ° C./min. At this time, the glass transition temperature was determined as the temperature at the intersection of the extension line of the base line and the extension line of the peak rising line (line on the low temperature side with respect to the peak apex).

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated in detail, this invention is not limited only to a following example.

<Production of toner>
-Polymerization of crystalline polyester resin (A)-
In a heat-dried three-necked flask, 100% by mass of a monomer component composed of 100 mol% of decanedicarboxylic acid and 100 mol% of nonanediol and 0.3% by mass of dibutyltin oxide were added, The air was brought into an inert atmosphere with nitrogen gas, and the mixture was stirred and refluxed at 180 ° C. for 5 hours with mechanical stirring.
Thereafter, the temperature was gradually raised to 230 ° C. under reduced pressure, and the mixture was stirred for 2 hours. When it became viscous, it was cooled with air, the reaction was stopped, and the crystalline polyester resin (A) was polymerized.
When the molecular weight measurement (polystyrene conversion) by gel permeation chromatography was performed, the weight average molecular weight (Mw) of the obtained crystalline polyester resin (A) was 23300, and the number average molecular weight (Mn) was 7300.
Further, when the melting point (Tm) of the crystalline polyester resin (A) was measured by the above-described measurement method using a differential scanning calorimeter (DSC), it showed a clear endothermic peak, and the endothermic peak temperature was 72.2. ° C.

-Preparation of crystalline polyester resin particle dispersion (A)-
Subsequently, the crystalline polyester resin (A) was used to prepare a resin particle dispersion having the following composition.
-Crystalline polyester resin (A): 90 parts by mass-Ionic surfactant (Neogen RK, Daiichi Kogyo Seiyaku): 1.8 parts by mass-Ion exchange water: 210 parts by mass The above components are heated to 100 ° C. Then, after dispersion with IKA Ultra Turrax T50, the dispersion is heated to 110 ° C. with a pressure discharge type gorin homogenizer for 1 hour, and a resin particle dispersion liquid (A )

-Polymerization of crystalline polyester resin (B)-
Into a heat-dried three-necked flask, 100% by mass of a monomer component composed of 100 mol% of dimethyl sebacate and 100 mol% of 1,6-hexanediol and 0.4% by mass of tin dioctanoate were added, and then reduced pressure operation was performed. The air in the container was brought into an inert atmosphere with nitrogen gas, and stirred and refluxed at 180 ° C. for 5 hours with mechanical stirring.
Thereafter, the temperature was gradually raised to 230 ° C. under reduced pressure, and the mixture was stirred for 4 hours. When it became viscous, it was cooled with air, the reaction was stopped, and the crystalline polyester resin (B) was polymerized.
When molecular weight measurement (polystyrene conversion) was performed by gel permeation chromatography, the obtained crystalline polyester resin (B) had a weight average molecular weight (Mw) of 21,000 and a number average molecular weight (Mn) of 6300.
Further, when the melting point (Tm) of the crystalline polyester resin (B) was measured using a differential scanning calorimeter (DSC) by the above-described measuring method, it showed a clear endothermic peak, and the endothermic peak temperature was 65.2. ° C.

-Preparation of crystalline polyester resin particle dispersion (B)-
Next, a resin particle dispersion having the following composition was prepared using the crystalline polyester resin (B).
-Crystalline polyester resin (B): 90 parts by mass-Ionic surfactant (Neogen RK, Daiichi Kogyo Seiyaku): 1.8 parts by mass-Ion exchange water: 210 parts by mass The above ingredients are heated to 100 ° C. Then, after dispersion with IKA Ultra Turrax T50, the dispersion is heated to 110 ° C. with a pressure discharge type gorin homogenizer for 1 hour, and a resin particle dispersion (B) having an average particle size of 130 nm and a solid content of 30% by mass (B )

-Polymerization of amorphous polyester resin (1)-
-Bisphenol A ethylene oxide 2 mol adduct: 30 mol%
-Bisphenol A propylene oxide adduct: 70 mol%
・ Terephthalic acid: 80 mol%
・ Fumaric acid: 20 mol%
The above monomer is charged into a 5 liter flask equipped with a stirrer, nitrogen inlet tube, temperature sensor, and rectifying column. The temperature is raised to 190 ° C. over 1 hour, and the reaction system is uniformly stirred. Then, 1.0% by mass of tin dioctanoate was added to 100% by mass of the charged monomer.
Further, while distilling off the generated water, it took 6 hours from the same temperature to raise the temperature to 240 ° C., and continued the dehydration condensation reaction at 240 ° C. for another 2 hours, with a glass transition temperature of 62 ° C. and an acid value of 12. An amorphous polyester resin (1) having 5 mg KOH / g, a weight average molecular weight of 16,300, and a number average molecular weight of 4000 was obtained.

-Polymerization of amorphous polyester resin (2)-
-Bisphenol A propylene oxide 2 mol adduct: 80 mol%
・ Trimethylolpropane: 20 mol%
-Trimellitic anhydride: 5 mol%
・ Terephthalic acid: 85 mol%
-Dodecenyl succinic acid: 10 mol%
A monomer other than trimellitic anhydride was charged into a 5 liter flask equipped with a stirrer, nitrogen inlet tube, temperature sensor, and rectifying column, and the temperature was raised to 190 ° C. over 1 hour. Was confirmed to be uniformly stirred, and then 0.6% by mass of tin dihexanoate was added to 100% by mass of the charged monomer.
Further, 6 hours from the same temperature was required while distilling off the generated water, the temperature was raised to 240 ° C., and the dehydration condensation reaction was further continued at 240 ° C. until the softening point reached 110 ° C. Next, the temperature was lowered to 190 ° C., and 5 mol% of trimellitic anhydride was gradually added, and the reaction was continued for 1 hour at the same temperature. The glass transition temperature was 63 ° C., the acid value was 17 mg KOH / g, and the weight average molecular weight was 42000. A non-crystalline polyester resin (2) having a number average molecular weight of 8,000 was obtained.

-Polymerization of amorphous polyester resin (3)-
-Bisphenol A ethylene oxide 2 mol adduct: 30 mol%
-Bisphenol A propylene oxide adduct: 70 mol%
・ Terephthalic acid: 45 mol%
・ Fumaric acid: 40 mol%
-Dodecenyl succinic acid: 15 mol%
The above monomer is charged into a 5 liter flask equipped with a stirrer, nitrogen inlet tube, temperature sensor, and rectifying column. The temperature is raised to 190 ° C. over 1 hour, and the reaction system is uniformly stirred. Then, 0.8% by mass of tin distearate was added to 100% by mass of the charged monomer.
Further, while distilling off the generated water, it took 6 hours from the same temperature to increase the temperature to 240 ° C., and continued the dehydration condensation reaction at 240 ° C. for another 3 hours. The glass transition temperature was 57 ° C., and the acid value was 14.6 mgKOH. / G, a non-crystalline polyester resin (3) having a weight average molecular weight of 20000 and a number average molecular weight of 6500 was obtained.

-Polymerization of amorphous polyester resin (4)-
-Bisphenol A ethylene oxide 2-mol adduct: 50 mol%
-Bisphenol A propylene oxide adduct: 50 mol%
-Trimellitic anhydride: 2 mol%
・ Terephthalic acid: 75 mol%
-Dodecenyl succinic acid: 23 mol%
The glass transition temperature was 58 ° C. in exactly the same manner as the non-crystalline polyester resin (2) except that the above monomer was used and 0.8% by mass of titanium octoate was used instead of 0.6% by mass of tin dihexanoate. An amorphous polyester resin (4) having an acid value of 11.8 mgKOH / g, a weight average molecular weight of 30000 and a number average molecular weight of 5500 was obtained.

-Polymerization of amorphous polyester resin (5)-
-Bisphenol A ethylene oxide 2-mol adduct: 20 mol%
-Bisphenol A propylene oxide adduct: 80 mol%
・ Terephthalic acid: 60 mol%
・ Fumaric acid: 25 mol%
-Dodecenyl succinic acid: 15 mol%
The above monomer is charged into a 5 liter flask equipped with a stirrer, nitrogen inlet tube, temperature sensor, and rectifying column. The temperature is raised to 190 ° C. over 1 hour, and the reaction system is uniformly stirred. Then, 0.8% by mass of hexaethylditin oxide was added to 100% by mass of the charged monomer.
Further, while distilling off the generated water, it took 6 hours from the same temperature to increase the temperature to 240 ° C., and continued the dehydration condensation reaction at 240 ° C. for another 4 hours. The glass transition temperature was 59 ° C., and the acid value was 13.6 mgKOH. / G, a non-crystalline polyester resin (5) having a weight average molecular weight of 16000 and a number average molecular weight of 4200 was obtained.

-Polymerization of non-crystalline polyester resin (6)-
-Bisphenol A ethylene oxide 2-mol adduct: 20 mol%
-Bisphenol A propylene oxide adduct: 80 mol%
・ Terephthalic acid: 75 mol%
・ Fumaric acid: 25 mol%
The above monomer is charged into a 5 liter flask equipped with a stirrer, nitrogen inlet tube, temperature sensor, and rectifying column, and the temperature is raised to 190 ° C. over 1 hour, and the reaction system is uniformly stirred. After confirming the above, 1.2% by mass of dibutyltin oxide was added to 100% by mass of the charged monomer.
Further, while distilling off the water produced, it took 6 hours from the same temperature to increase the temperature to 230 ° C., and continued the dehydration condensation reaction at 230 ° C. for another 2 hours. An amorphous polyester resin (6) having 0 mg / KOH, a weight average molecular weight of 18000, and a number average molecular weight of 5200 was obtained.

-Polymerization of amorphous polyester resin (7)-
-Bisphenol A ethylene oxide 2-mol adduct: 40 mol%
-Bisphenol A propylene oxide adduct: 60 mol%
・ Terephthalic acid: 55 mol%
・ Fumaric acid: 45 mol%
The above monomer is charged into a 5 liter flask equipped with a stirrer, nitrogen inlet tube, temperature sensor, and rectifying column. The temperature is raised to 190 ° C. over 1 hour, and the reaction system is uniformly stirred. Then, 0.8% by mass of tin diacetate was added to 100% by mass of the charged monomer.
Further, while distilling off the generated water, it took 6 hours from the same temperature to raise the temperature to 240 ° C., and continued the dehydration condensation reaction at 240 ° C. for another 3 hours. The glass transition temperature was 60 ° C., the acid value was 13.6 mgKOH A non-crystalline polyester resin (7) having a weight average molecular weight of 15000 and a number average molecular weight of 5500 was obtained.

-Polymerization of amorphous polyester resin (8)-
In the polymerization of the amorphous polyester resin (1), the glass transition temperature was 61 ° C. and the acid value was 12.2 except that the tin dioctanoate was changed from 1.0 mass% to 1.0 mass% titanium sebacate. An amorphous polyester resin (8) having 8 mg KOH / g, a weight average molecular weight of 14500, and a number average molecular weight of 3800 was obtained.

-Polymerization of non-crystalline polyester resin (9)-
In the polymerization of the amorphous polyester resin (1), the glass transition temperature was 62 ° C. and the acid value was 11.1 except that the tin dioctanoate was changed from 1.0% by mass to 1.5% by mass of nonadecanoate. An amorphous polyester resin (9) having 5 mg KOH / g, a weight average molecular weight of 18500, and a number average molecular weight of 4300 was obtained.

-Preparation of non-crystalline polyester resin particle dispersion (1)-
・ Amorphous polyester resin (1): 100 parts by mass ・ Ethyl acetate: 50 parts by mass ・ Isopropyl alcohol: 15 parts by mass Ethyl acetate was introduced into a 5 L separable flask, and then the above resin was gradually introduced. The mixture was stirred with a motor and completely dissolved to obtain an oil phase. To this stirred oil phase, a 10% by mass aqueous ammonia solution is gradually added dropwise with a dropper so that the total amount becomes 3 parts by mass, and further 230 parts by mass of ion-exchanged water is gradually added dropwise at a rate of 10 ml / min. Phase-emulsification was performed, and the solvent was removed while reducing the pressure with an evaporator to obtain a resin particle dispersion (1) containing an amorphous polyester resin (1). The volume average particle diameter of the resin particles dispersed in this dispersion was 150 nm. The resin particle concentration of the dispersion was adjusted to 30% by mass with ion exchange water.

-Preparation of non-crystalline polyester resin particle dispersions (2) to (9)-
In the preparation of the non-crystalline polyester resin particle dispersion (1), the non-crystalline polyester resin (1) is converted into non-crystalline polyester resin (2), (3), (4), (5), (6), ( 7), (8), and (9) were carried out in the same manner except that the non-crystalline polyester resin particle dispersions (2), (3), (4), (5), (6), ( 7), (8) and (9) were obtained. The respective volume average particle diameters are shown in Table 1.

-Preparation of Colorant Particle Dispersion 1-
Carbon black (Cabot Corp .: Regal 330): 50 parts by mass Anionic surfactant (Nippon Oil & Fats Co., Ltd .: Newrex R): 2 parts by mass Ion-exchanged water: 198 parts by mass Then, after pre-dispersing for 10 minutes with a homogenizer (IKA Ultra Tarrax), dispersion processing is performed for 15 minutes at a pressure of 245 Mpa using an optimizer (counter-impact type wet pulverizer: Sugino Machine), and the central particle size of the colorant particles is A colorant particle dispersion 1 having a solid content of 20.0% by mass at 354 nm was obtained.

-Preparation of Colorant Particle Dispersion 2-
-Blue pigment (copper phthalocyanine B15: 3: manufactured by Dainichi Seika): 50 parts by mass-Ionic surfactant (Neogen RK, Daiichi Kogyo Seiyaku): 5 parts by mass-Ion exchange water: 195 parts by mass The above ingredients are mixed Then, after being dispersed for 10 minutes by a homogenizer (IKA Ultra Tarrax), dispersion processing is performed for 15 minutes at a pressure of 245 Mpa using an optimizer (counter-impact type wet pulverizer: Sugino Machine), and the central particle diameter of the colorant particles is determined. A colorant particle dispersion 2 having a solid content of 20.0% by mass at 462 nm was obtained.

-Preparation of release agent particle dispersion 1-
-Olefin wax (melting point: 88 ° C): 90 parts by mass-Ionic surfactant (Neogen RK, Daiichi Kogyo Seiyaku): 1.8 parts by mass-Ion exchange water: 210 parts by mass or more heated to 100 ° C After dispersion with IKA Ultra Turrax T50, the dispersion was heated to 110 ° C. with a pressure discharge type gorin homogenizer and dispersed for 1 hour to obtain a release agent particle dispersion 1 having a center diameter of 180 nm and a solid content of 30% by mass. Obtained.

-Preparation of release agent particle dispersion 2-
-Polymerized ester wax (melting point: 75 ° C): 90 parts by mass-Ionic surfactant (Neogen RK, Daiichi Kogyo Seiyaku): 1.8 parts by mass-Ion-exchanged water: 210 parts by mass or more heated to 100 ° C Then, after dispersion with IKA Ultra Turrax T50, heat treatment is performed at 110 ° C. with a pressure discharge type gorin homogenizer and dispersion treatment is performed for 1 hour. Release agent particle dispersion liquid 2 having a center diameter of 230 nm and a solid content of 30% by mass Got.

-Preparation of Toner 1-
Non-crystalline polyester resin particle dispersion (1): 166 parts by mass Crystalline polyester resin particle dispersion (A): 50 parts by weight Colorant particle dispersion 2: 25 parts by weight Release agent particle dispersion 1 : 40 parts by mass The above ingredients were mixed and dispersed in a round stainless steel flask using Ultra Turrax T50. Subsequently, 0.20 part by mass of polyaluminum chloride was added thereto, and the dispersion operation was continued with an ultra turrax. The flask was heated to 48 ° C. with stirring in an oil bath for heating. After holding at 48 ° C. for 60 minutes, 60 parts by mass of the amorphous polyester resin particle dispersion (1) was gradually added thereto.
Thereafter, the pH of the solution in the flask was adjusted to 8.0 with a 0.5 mol / l aqueous sodium hydroxide solution, and then the stainless steel flask was sealed and heated to 90 ° C. while continuing to stir using a magnetic seal, Hold for 3 hours.

After completion of the reaction, the mixture was cooled, filtered, washed with ion exchange water, and then subjected to solid-liquid separation by Nutsche suction filtration. This was further redispersed in 1 L of ion exchange water at 40 ° C., and stirred and washed at 300 rpm for 15 minutes.
This was repeated five more times, and when the pH of the filtrate became 7.5 and the electric conductivity was 7.0 μS / cmt, solid-liquid separation was performed using No5A filter paper by Nutsche suction filtration. Next, vacuum drying is continued for 12 hours to have a so-called core-shell structure having a core layer containing a crystalline polyester resin and an amorphous polyester resin and a shell layer containing an amorphous polyester resin covering the core layer. Toner 1 was obtained.
When the particle size at this time was measured, the volume average particle size was 5.9 microns and the volume average particle size distribution index GSDv was 1.22. In addition, the particle shape factor SF1 obtained by shape observation with Luzex was 136.

-Preparation of Toner 2-
166 parts by mass of the amorphous polyester resin particle dispersion (1) is 166 parts by mass of the amorphous polyester resin particle dispersion (2), and 50 parts by mass of the crystalline polyester resin particle dispersion (A) is crystalline. 60 parts by mass of the non-crystalline polyester resin particle dispersion (2) is added to 60 parts by mass of the non-crystalline polyester resin particle dispersion (2) to 50 parts by mass of the polyester resin particle dispersion (B). A toner was prepared in the same manner as in the preparation of toner 1 except that the toner 2 was changed.
When the particle size at this time was measured, the volume average particle size was 6.3 microns, and the volume average particle size distribution index GSDv was 1.24. In addition, the particle shape factor SF1 obtained from shape observation by Luzex was 132.

-Production of Toner 3-
166 parts by mass of the amorphous polyester resin particle dispersion (1) is added to 166 parts by mass of the amorphous polyester resin particle dispersion (3), and 40 parts by mass of the release agent particle dispersion 1 is dispersed in the release agent particles. Toner 3 was obtained in the same manner as in Toner 1 except that the amount was changed to 40 parts by mass of Liquid 2.
When the particle size at this time was measured, the volume average particle size was 6.2 microns, and the volume average particle size distribution index GSDv was 1.20. Further, the shape factor SF1 of the particle determined by shape observation with Luzex was 130.

-Production of Toner 4-
166 parts by mass of the amorphous polyester resin particle dispersion (1) is added to 166 parts by mass of the amorphous polyester resin particle dispersion (4). A toner was produced in the same manner as in the production of the toner 1 except that the mass part was changed to 60 parts by mass of the amorphous polyester resin particle dispersion (2).
When the particle size at this time was measured, the volume average particle size was 6.5 microns, and the volume average particle size distribution index GSDv was 1.20. In addition, the particle shape factor SF1 determined by shape observation with Luzex was 135.

-Production of Toner 5-
Toner 5 was prepared in the same manner as toner 1 except that 166 parts by mass of the amorphous polyester resin particle dispersion (1) was changed to 166 parts by mass of the amorphous polyester resin particle dispersion (5). Got.
When the particle size at this time was measured, the volume average particle size was 5.8 microns, and the volume average particle size distribution index GSDv was 1.24. Further, the shape factor SF1 of the particle determined by shape observation with Luzex was 130.

-Production of Toner 6-
Toner 6 was obtained in the same manner as toner 1 except that 25 parts by mass of colorant particle dispersion 2 was changed to 25 parts by mass of colorant particle dispersion 1.
When the particle size at this time was measured, the volume average particle size was 5.8 microns, and the volume average particle size distribution index GSDv was 1.23. In addition, the particle shape factor SF1 obtained by shape observation with Luzex was 136.

-Production of Toner 7-
166 parts by mass of the amorphous polyester resin particle dispersion (1) is added to 166 parts by mass of the amorphous polyester resin particle dispersion (8). A toner was prepared in the same manner as in the preparation of the toner 1 except that the mass part was changed to 60 parts by mass of the amorphous polyester resin particle dispersion (8).
When the particle size at this time was measured, the volume average particle size was 6.0 microns and the volume average particle size distribution index GSDv was 1.23. In addition, the particle shape factor SF1 determined by shape observation with Luzex was 134.

-Production of Toner 8-
166 parts by mass of the amorphous polyester resin particle dispersion (1) is added to 166 parts by mass of the amorphous polyester resin particle dispersion (9). A toner was prepared in the same manner as in the preparation of the toner 1 except that the mass part was changed to 60 parts by mass of the non-crystalline polyester resin particle dispersion (9).
When the particle size at this time was measured, the volume average particle size was 5.9 microns and the volume average particle size distribution index GSDv was 1.25. In addition, the particle shape factor SF1 determined by shape observation with Luzex was 134.

-Production of Toner 9-
166 parts by mass of the amorphous polyester resin particle dispersion (1) is added to 166 parts by mass of the amorphous polyester resin particle dispersion (6). A toner was prepared in the same manner as in the preparation of the toner 1 except that the mass part was changed to 60 parts by mass of the amorphous polyester resin particle dispersion (6).
When the particle size at this time was measured, the volume average particle size was 6.5 microns, and the volume average particle size distribution index GSDv was 1.24. Further, the shape factor SF1 of the particle determined by shape observation with Luzex was 130.

-Production of Toner 10-
166 parts by mass of the amorphous polyester resin particle dispersion (1) is added to 166 parts by mass of the amorphous polyester resin particle dispersion (7). A toner was produced in the same manner as in the production of the toner 1 except that the mass part was changed to 60 parts by mass of the resin particle dispersion (7).
When the particle size at this time was measured, the volume average particle size was 5.7 microns, and the volume average particle size distribution index GSDv was 1.24. In addition, the particle shape factor SF1 obtained by shape observation with Luzex was 128.

<Addition of external additives>
Using Henschel mixer, 100 parts by mass of toner of toner 1, 0.8 part of hydrophobic titania treated with decylsilane having an average particle diameter of 15 nm, and 1.3 parts of hydrophobic silica (NY50, manufactured by Nippon Aerosil Co., Ltd.) with an average particle diameter of 30 nm are used. After blending for 10 minutes at a peripheral speed of 32 m / s, coarse particles were removed using a sieve having a mesh of 45 μm to obtain an externally added toner 1. Toners 2 to 10 were prepared in the same manner to obtain externally added toners 2 to 10.

<Creation of carrier>
Ferrite particles (average particle size 50 μm, volume electric resistance 10 ⁸ Ω · cm): 100 parts by mass Toluene: 14 parts by mass Perfluorooctylethyl acrylate / methyl methacrylate copolymer (copolymerization ratio (molar ratio) 20) 80, Mw = 50,000): 1.6 parts by mass. Carbon black (VXC-72; manufactured by Cabot Corporation): 0.12 parts by mass. Cross-linked melamine resin particles (number average particle size: 0.3 μm): 0.3 Of the above components, the components excluding the ferrite particles are dispersed with a stirrer for 10 minutes to prepare a film-forming liquid, and the film-forming liquid and the ferrite particles are placed in a vacuum degassing kneader and heated at 60 ° C. for 30 minutes. After stirring for a minute, the pressure was reduced and toluene was distilled off to form a resin film on the surface of the ferrite particles to produce a carrier.

<Production of developer>
Developer 1 was prepared by stirring 94 parts by mass of carrier and 6 parts by mass of externally added toner 1 at 40 rpm for 20 minutes using a V-blender and sieving with a sieve having a 177 μm mesh. Developers 2 to 10 were prepared in the same manner for externally added toners 2 to 10.

  Table 2 shows various materials used for the production of each toner and the glass transition temperature (Tg) of the toner.

<Evaluation>
The obtained developers 1 to 10 were evaluated with a commercially available electrophotographic copying machine Docu Center Color a450 (manufactured by Fuji Xerox Co., Ltd.).
In the evaluation test, 5000 text images corresponding to an image area ratio of 5% were printed on an A4 size paper (Fuji Xerox Co., Ltd., J paper) in an environment of 28 ° C./85% RH over one day. Then, after printing 5000 sheets, the apparatus was turned off to stop it completely and left in this state for 24 hours in the same environment.
After the apparatus was completely stopped for 24 hours, the apparatus was turned on and the same character images were continuously printed on the same paper as described above.
The image was formed by setting the fixing temperature to 120 ° C. and the process speed to 160 mm / s. In addition, when printing 5000 sheets, the power supply of the completely stopped apparatus was turned on and the apparatus was warmed up as usual.
In contrast, when reprinting is performed after being left for 24 hours, development is performed so that the toner in the developing device is stirred and not recharged until the fixing machine is heated and fixing is possible. The printer was controlled so as not to operate, and at the same time as the fixing machine was heated (at this point, the developer was started and restarted), and a print test was conducted.
In the above series of print tests, the initial (10th of 5000 sheets), 5000 sheets (5000th sheet of 5000 sheets), and 24 hours of reprinting (10th sheet after starting reprinting) The image quality was evaluated, and the charge amount of the toner was evaluated at almost the same timing. The results are shown in Table 3.

  The charge amount, charge rate decrease, and image quality evaluation method and evaluation criteria shown in Table 3 are as follows.

-Measurement of charge amount-
When the first 10 sheets of the 5000-sheet print test have been printed ("Initial" column in Table 3), and immediately after the 5000-sheet print test is completed ("5000 sheets after" column in Table 3) , Development on the mag sleeve in the developing unit immediately before turning on the power for the reprinting test after being left for 24 hours (in the column of “After 5,000 sheets are printed and then left for 24 hours” in Table 3). The agent was collected and measured with a TB200 manufactured by Toshiba under the conditions of 25 ° C. and 55% RH.

-Charge reduction rate-
The decrease in charging rate was calculated based on the following formula.
Reduction in charge rate = (toner charge amount immediately after turning on the apparatus for the reprint test after being left for 24 hours) / (toner charge amount immediately after completion of print test for 5000 sheets) × 100 (%)

-Image quality evaluation-
The image quality was evaluated according to the following evaluation criteria by visually observing the surface on which the character image of the obtained printed matter was formed.
○: No fogging and blurring of characters, no problem △: There is more remarkable blurring of characters compared to the case of “○” evaluation, but there is no practical problem ×: There is blurring of fogging and characters, practical Unusable

Claims (10)

  A toner for developing an electrostatic charge image, comprising at least a crystalline resin, an amorphous resin, and an organometallic compound having an alkyl group having 5 to 18 carbon atoms.   The organometallic compound having an alkyl group having 5 to 18 carbon atoms is a catalyst used for polymerization of at least one resin selected from the crystalline resin and the amorphous resin. The toner for developing an electrostatic image according to claim 1.   2. The electrostatic charge according to claim 1, wherein the organometallic compound having an alkyl group having 5 to 18 carbon atoms includes any one metal element selected from Sn element and Ti element. Toner for image development.   The electrostatic image developing toner according to claim 1, wherein the crystalline resin is a crystalline polyester resin.   The electrostatic image developing toner according to claim 1, wherein the amorphous resin is an amorphous polyester resin.   An electrostatic charge image developer comprising: a toner including at least a crystalline resin, an amorphous resin, and an organometallic compound having an alkyl group having 5 to 18 carbon atoms. It is detachable from an image forming apparatus having at least a toner image forming unit, and stores a developer to be supplied to the toner image forming unit.
The toner cartridge, wherein the developer includes a toner including at least a crystalline resin, an amorphous resin, and an organometallic compound having an alkyl group having 5 to 18 carbon atoms. It is detachable from the image forming apparatus,
An image holding member; and at least a toner image forming unit that contains the developer and supplies the developer to an electrostatic latent image formed on the surface of the image holding member to form a toner image.
The developer is an alkyl group having 5 to 18 carbon atoms dispersed in at least one resin selected from a crystalline resin, an amorphous resin, and the crystalline resin and the amorphous resin. A process cartridge comprising: a toner containing at least an organometallic compound having the above. A charging step for charging the surface of the image carrier, an electrostatic latent image forming step for forming an electrostatic latent image on the charged surface of the image carrier, and developing the electrostatic latent image with the developer to form a toner image. A toner image forming step for forming the toner image, a transfer step for transferring the toner image to the surface of the recording medium, and a fixing step for fixing the toner image transferred to the surface of the recording medium,
An image forming method, wherein the developer includes a toner including at least a crystalline resin, an amorphous resin, and an organometallic compound having an alkyl group having 5 to 18 carbon atoms. An image carrier, a charging unit that charges the surface of the image carrier, an electrostatic latent image forming unit that forms an electrostatic latent image on the charged surface of the image carrier, and the developer At least a toner image forming unit that forms a toner image by developing, a transfer unit that transfers the toner image to the surface of the recording medium, and a fixing unit that fixes the toner image transferred to the surface of the recording medium,
The developer is an alkyl group having 5 to 18 carbon atoms dispersed in at least one resin selected from a crystalline resin, an amorphous resin, and the crystalline resin and the amorphous resin. And an organometallic compound having a toner.