JP2015152912A - Polyester resin for toner, toner for electrostatic charge image development, electrostatic charge image developer, toner cartridge, process cartridge, image forming apparatus, and image forming method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polyester resin for a toner, which is used for a toner for electrostatic charge image development excellent in low-temperature fixability.SOLUTION: The polyester resin for a toner contains a repeating unit (A) derived from a polyvalent carboxylic acid, a repeating unit (B) derived from a polyhydric alcohol represented by general formula (1) below, and a repeating unit (C) derived from a linear aliphatic polyhydric alcohol, in which the total content of the repeating unit (B) and the repeating unit (C) is 60 mol% or more and 100 mol% or less in repeating units derived from the whole alcohols, and a molar ratio of (repeating unit (B))/(repeating unit (C)) is 0.1 or more and 1.0 or less. In general formula (1), Rand Rrepresent hydrogen or a methyl group; Lrepresents a linear alkylene group which may have an ester group or an ether group; Land Lrepresent a divalent connecting group such as a cyclic alkylene group, an arylene group, or a combination of these groups; and Aand Arepresent a rosin ester group.

Description

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

A method of visualizing image information through a process of forming an electrostatic latent image and developing it, such as electrophotography, is currently used in various fields.
In this method, the entire surface of the photosensitive member (latent image holding member) is charged, and then the surface of the photosensitive member is exposed to laser light according to image information to form an electrostatic latent image. Next, the electrostatic latent image is developed with a developer containing toner to form a toner image, and finally the toner image is transferred and fixed on the surface of the recording medium.

The following toners are known as toners applied to the electrophotographic method as described above.
For example, Patent Document 1 discloses a compound represented by the following chemical formula (where X is aliphatic or aromatic, and Y is a purified rosin residue, a disproportionated rosin residue, or a hydrogenated rosin residue). An electrophotographic toner comprising resin particles made of a polyester resin, which is a basic group and n = 0 to 1) is an essential component of an alcohol component.

  Patent Document 2 contains a repeating unit derived from a dicarboxylic acid component and a repeating unit derived from a dialcohol component represented by the following general formula (1), and has an acid value of 3 mgKOH / g or more and 30 mgKOH / g. A toner containing the following polyester resin for toner is disclosed.

(In the general formula (1), R ¹ and R ² each independently represent hydrogen or a methyl group. L ¹ , L ² , and L ³ each independently represent a carbonyl group, an ester group, an ether group, a sulfonyl group, and a substituent. A divalent linking group selected from the group consisting of a chain alkylene group which may have a group, a cyclic alkylene group which may have a substituent, an arylene group which may have a substituent, and combinations thereof And L ¹ and L ² or L ¹ and L ³ may form a ring, and A ¹ and A ² each represent a rosin ester group.)

JP 2012-172027 A JP 2012-229413 A

  An object of the present invention is to provide a polyester resin for toner that is used in an electrostatic charge image developing toner excellent in low-temperature fixability.

The above problem is solved by the following means. That is,
The invention according to claim 1 is a polyhydric alcohol comprising (A) a polyvalent carboxylic acid component, (B) a polyhydric alcohol represented by the following general formula (1), and (C) a chain aliphatic polyhydric alcohol. The total amount of the polyhydric alcohol represented by (B) the general formula (1) and the (C) chain aliphatic polyhydric alcohol in the total alcohol component. The molar ratio of the polyhydric alcohol represented by the general formula (1) and the (C) chain aliphatic polyhydric alcohol [(B) / (C) ] Is a polyester resin for toners of 0.1 or more and 1.0 or less.

[In General Formula (1), R ¹ and R ² each independently represent hydrogen or a methyl group. L ¹ represents a chain alkylene group which may have a substituent, or a divalent group obtained by combining the chain alkylene group with an ester group or an ether group, and L ² and L ³ are each independently , A carbonyl group, an ester group, an ether group, a sulfonyl group, a chain alkylene group which may have a substituent, a cyclic alkylene group which may have a substituent, an arylene group which may have a substituent, and It represents a divalent linking group selected from the group consisting of a divalent group in which they are combined, and L ¹ and L ² or L ¹ and L ³ may form a ring. A ¹ and A ² represent a rosin ester group. ]

  The invention according to claim 2 is characterized in that the (C) chain aliphatic polyhydric alcohol is at least selected from the group consisting of 1,3-propanediol, ethylene glycol, 1,2-propanediol, and neopentyl glycol. The polyester resin for toner according to claim 1, which is one type.

  In the invention according to claim 3, (A) the polyvalent carboxylic acid component is at least two kinds of dicarboxylic acid containing an aromatic structure and dicarboxylic acid containing a chain aliphatic structure having 4 or less carbon atoms. Item 3. A polyester resin for toner according to Item 1 or Item 2.

The invention according to claim 4
An electrostatic charge image developing toner comprising the toner polyester resin according to any one of claims 1 to 3.

The invention according to claim 5
An electrostatic charge image developer comprising the electrostatic charge image developing toner according to claim 4.

The invention according to claim 6
Containing the electrostatic image developing toner according to claim 4;
The toner cartridge is detachable from the image forming apparatus.

The invention according to claim 7 provides:
A developing means for accommodating the electrostatic charge image developer according to claim 5 and developing a latent image formed on the surface of the latent image holding member with the electrostatic charge image developer to form a toner image,
It is a process cartridge that can be attached to and detached from the image forming apparatus.

The invention according to claim 8 provides:
A latent image carrier,
Charging means for charging the surface of the latent image carrier;
An electrostatic latent image forming means for forming an electrostatic latent image on the surface of the latent image holding member;
Developing means for containing the electrostatic charge image developer according to claim 5 and developing the electrostatic latent image with the electrostatic charge image developer to form a toner image;
Transfer means for transferring the toner image to a recording medium;
Fixing means for fixing the toner image on the recording medium;
An image forming apparatus.

The invention according to claim 9 is:
A charging step for charging the surface of the latent image carrier,
An electrostatic latent image forming step of forming an electrostatic latent image on the surface of the latent image holder;
A developing step of developing the electrostatic latent image with the electrostatic charge image developer according to claim 5 to form a toner image;
A transfer step of transferring the toner image to a recording medium;
A fixing step of fixing the toner image on the recording medium;
Is an image forming method.

According to the invention of claim 1, the total amount of the polyhydric alcohol component of (B) and the polyhydric alcohol component of (C) containing an aromatic structure in L ¹ in the general formula (1) is in the above range. Or a polyester for toners suitable for an electrostatic charge image developing toner having excellent low-temperature fixability compared to the case where the molar ratio of the polyhydric alcohol component of (B) / (C) is outside the above range. A resin is provided.
According to the second aspect of the present invention, the polyhydric alcohol component (C) is used for a toner for developing an electrostatic image having excellent low-temperature fixability as compared with a case where the repeating unit is derived from other than the alcohol component. A polyester resin for toner is provided.
According to the invention of claim 3, (A) it is used for a toner for developing an electrostatic image having excellent low-temperature fixability as compared with a case where the polyvalent carboxylic acid component is only a polyvalent carboxylic acid containing an aromatic structure. A polyester resin for toner is provided.

According to the invention of claim 4, the total amount of the polyhydric alcohol component of (B) and the polyhydric alcohol component of (C) containing an aromatic structure in L ¹ in the general formula (1) is in the above range. Or a toner for developing an electrostatic charge image having excellent low-temperature fixability as compared with a case where the molar ratio of the polyhydric alcohol component of (B) to the polyhydric alcohol component of (C) contains a polyester resin outside the above range. Is done.

According to the invention of claim 5, the total amount of the polyhydric alcohol component of (B) and the polyhydric alcohol component of (C), which contains an aromatic structure in L ¹ in the general formula (1), is in the above range. Compared with the case where a toner for developing an electrostatic charge image containing a polyester resin in which the molar ratio of the polyhydric alcohol component (B) / (C) polyhydric alcohol component is outside the above range is applied, the low temperature fixability is excellent. An electrostatic charge image developer is provided.

According to the invention of claim 6, 7, 8, 9, polyhydric alcohol component of which in L ¹ in the general formula (1) containing an aromatic structure, and a polyhydric alcohol component (B) (C) As compared with the case where a toner for developing an electrostatic charge image containing a polyester resin having a molar ratio of the polyhydric alcohol component (B) / polyhydric alcohol component (C) outside the above range is applied. A toner cartridge, a process cartridge, an image forming apparatus, and an image forming method excellent in low-temperature fixability are provided.

It is a figure explaining the state of a screw about an example of a screw extruder used for manufacture of toner concerning this embodiment. 1 is a schematic configuration diagram illustrating an example of an image forming apparatus according to an exemplary embodiment. It is a schematic block diagram which shows an example of the process cartridge which concerns on this embodiment.

  Hereinafter, the polyester resin for toner, the toner for developing an electrostatic charge image, the electrostatic charge image developer, the toner cartridge, the process cartridge, the image forming apparatus, and the image forming method of the present invention will be described in detail with reference to an exemplary embodiment. .

<Polyester resin for toner>
The polyester resin for toner according to the exemplary embodiment includes (A) a polyvalent carboxylic acid component, (B) a polyhydric alcohol represented by the following general formula (1), and (C) a chain aliphatic polyhydric alcohol. A polycondensate of a polyhydric alcohol component, and the total amount of (B) the polyhydric alcohol represented by the general formula (1) and (C) the chain aliphatic polyhydric alcohol is in the total alcohol component. The molar ratio of the polyhydric alcohol represented by the general formula (1) and the (C) chain aliphatic polyhydric alcohol [(B) / (C)] is 0.1 or more and 1.0 or less.

In the general formula (1), R ¹ and R ² each independently represents hydrogen or a methyl group. L ¹ represents a chain alkylene group which may have a substituent, or a divalent group obtained by combining the chain alkylene group with an ester group or an ether group, and L ² and L ³ are each independently , A carbonyl group, an ester group, an ether group, a sulfonyl group, a chain alkylene group which may have a substituent, a cyclic alkylene group which may have a substituent, an arylene group which may have a substituent, and It represents a divalent linking group selected from the group consisting of a divalent group in which they are combined, and L ¹ and L ² or L ¹ and L ³ may form a ring. A ¹ and A ² represent a rosin ester group.

The polyester resin for toner according to the present embodiment achieves low-temperature fixability when applied to an electrostatic charge image developing toner due to the structure described above.
The reason for this is not clear or is considered to be as follows.

Rosin is a molecule with high hydrophobicity and large volume and molecular weight. The polyester resin containing the rosin skeleton in the side chain has a property that it is difficult to contain water. When this polyester resin is applied to a toner, chargeability (particularly chargeability under high temperature and high humidity) can be improved.
However, polyester resins that regularly contain a rosin skeleton in the side chain tend to have a slow decrease in viscosity with respect to temperature due to the bulkiness and rigidity of the rosin skeleton. Is not sufficient, and various studies have been made at present.

In the present embodiment, the polyhydric alcohol component used to obtain the polyester resin includes (B) a polyhydric alcohol represented by the general formula (1) and (C) a chain aliphatic polyhydric alcohol. One of the features is the use.
(B) L ¹ in the general formula (1) includes a polyhydric alcohol represented by the general formula (1) which is a chain alkylene group which may include an ester group or an ether group, and also includes a chain aliphatic group. (C) It is thought that by using together with the chain aliphatic polyhydric alcohol, flexibility can be imparted to the main chain of the polyester resin. Due to the flexibility of the main chain, the bulkiness and rigidity of the rosin skeleton are alleviated, and so-called low-temperature fixing can be realized.
In particular, in this embodiment, the total amount of (B) the polyhydric alcohol represented by the general formula (1) and (C) the chain aliphatic polyhydric alcohol is 60 mol% or more and 100 mol% in the total alcohol components. And (B) the molar ratio of polyhydric alcohol represented by general formula (1) / (C) chain aliphatic polyhydric alcohol is 0.1 or more and 1.0 or less. Yes. By setting the content and molar ratio as described above, the main chain is imparted with flexibility while maintaining high chargeability due to the rosin skeleton of the side chain, and a decrease in viscosity at low temperatures can be exhibited. it is conceivable that.
For these reasons, the polyester resin according to the present embodiment is suitable for toner applications, and can achieve low-temperature fixability when applied to toner.

In Patent Document 1 described above, a polyester resin that regularly contains a rosin skeleton in the side chain is disclosed, but as a specific example, a compound represented by the above chemical formula that contains a bisphenol A skeleton in X is disclosed. There is only. With the structure of this specific example, the bulkiness of the rosin skeleton as described above, it is difficult to obtain the flexibility of the main chain that relaxes the rigidity, and the viscosity decreases at a low temperature like the polyester resin according to this embodiment. Is considered difficult to express.
Further, in Patent Document 2 described above, a polyester resin that regularly contains a rosin skeleton in the side chain is disclosed, but as a specific example, other dialcohol components are represented by the general formula (1). Only a structure in which many alcohol components are used is disclosed. With such a structure, the bulkiness of the rosin skeleton, the flexibility of the main chain that relaxes the rigidity is difficult to obtain, and it is difficult to express a decrease in viscosity at a low temperature like the polyester resin according to this embodiment. Conceivable.

In this embodiment, when L ¹ in the general formula (1) includes an alkylene group having 3 or less carbon atoms, includes an alkylene group having a methyl group as a substituent, or includes an ester group or an ether group. Furthermore, when the chain aliphatic group in the chain aliphatic polyhydric alcohol is an alkylene group having 3 or less carbon atoms, or when it is an alkylene group having a methyl group as a substituent, the repeating unit is It is presumed that it is difficult to take a regular structure in which the main chain structure of the polyester resin is determined because it becomes asymmetric or easily takes a bent structure derived from an alkyl group or an ester / ether group skeleton. It is considered that this irregularity of the main chain structure can effectively alleviate the bulkiness and rigidity of the rosin skeleton, and give preferable flexibility, thereby achieving a lower viscosity at a lower temperature.

  Hereinafter, a monomer component for obtaining a polyester resin for toner according to the present embodiment (hereinafter referred to as a specific polyester resin), (A) a polyvalent carboxylic acid component, (B) a polyvalent compound represented by the general formula (1). The monohydric alcohol and the (C) chain aliphatic polyhydric alcohol will be described in detail.

[(A) polyvalent carboxylic acid component]
The (A) polyvalent carboxylic acid component used to obtain the specific polyester resin will be described.
(A) As a polyvalent carboxylic acid component, at least 1 sort (s) chosen from the group which consists of the aromatic dicarboxylic acid containing an aromatic structure and the aliphatic dicarboxylic acid containing an aliphatic structure as shown below is preferable.
Specific examples of the aromatic dicarboxylic acid and the aliphatic dicarboxylic acid include aromatic dicarboxylic acids such as phthalic acid, isophthalic acid, terephthalic acid, 1,4-naphthalenedicarboxylic acid, and 2,6-naphthalenedicarboxylic acid; Oxalic acid, malonic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, succinic acid, glutaric acid, adipic acid, sebacic acid, azelaic acid, dimer acid, branched chain having 1 to 20 carbon atoms Aliphatic dicarboxylic acids such as alkyl succinic acid, branched chain alkenyl succinic acid having 1 to 20 carbon atoms; anhydrides of these acids; and alkyls of these acids (1 to 3 carbon atoms) ) Ester; and the like.
These aromatic dicarboxylic acids and aliphatic dicarboxylic acids may be used alone or in combination of two or more.
Among these, aromatic dicarboxylic acids such as isophthalic acid and terephthalic acid, succinic acid, and the like from the viewpoints of toner durability, fixability and colorant dispersibility when applied to toner, and easy availability. Aliphatic dicarboxylic acids such as acid, glutaric acid, sebacic acid and azelaic acid are preferred.

In addition, from the viewpoint of improving the low-temperature fixability of the toner when applied to the toner, (A) the polyvalent carboxylic acid component includes a dicarboxylic acid containing an aromatic structure (aromatic dicarboxylic acid), carbon It is preferable to use in combination with a dicarboxylic acid containing a chain aliphatic structure having a number of 4 or less. Here, the number of carbon atoms of 4 or less means that the number of carbon atoms in the chain aliphatic structure is 4 or less, excluding the carbon atoms constituting the carboxy group.
Specifically, aromatic dicarboxylic acids such as isophthalic acid, terephthalic acid, phthalic anhydride, 1,4-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, succinic acid (carbon number 2), adipic acid (carbon It is preferable to use together with aliphatic dicarboxylic acid, such as number 4) and glutaric acid (carbon number 3).
Thus, when using together 2 types of dicarboxylic acid components, 2 mol% or more and 15 mol% or less (preferably 3 mol% or more and 10 mol% or less) in all the dicarboxylic acid components used together are chain | strand-shaped with 4 or less carbon atoms. A dicarboxylic acid containing an aliphatic structure is desirable from the viewpoint of the balance between fixability and powder characteristics when applied to a toner.

In addition, trivalent or higher carboxylic acids may be used as the (A) polyvalent carboxylic acid component as long as the effects of the present embodiment are not impaired. However, the content of the trivalent or higher carboxylic acid in the (A) polyvalent carboxylic acid component is preferably 10 mol% or less (preferably 5 mol% or less).
Examples of the trivalent or higher carboxylic acids include trimellitic acid, pyromellitic acid, naphthalenetricarboxylic acid, benzophenone tetracarboxylic acid, biphenyltetracarboxylic acid, and aromatic carboxylic acids such as anhydrides thereof. Even if it uses, 2 or more types may be used together.
The trivalent or higher aromatic carboxylic acid is preferably trimellitic anhydride from the viewpoint of availability and reactivity.

[(B) Polyhydric alcohol represented by general formula (1)]
Next, the polyhydric alcohol represented by (B) General formula (1) which is one of the polyhydric alcohol components used in order to obtain specific polyester resin is demonstrated.
The polyhydric alcohol represented by the following general formula (1) is a so-called diol containing two rosin ester groups in one molecule and having two alcoholic hydroxyl groups in the molecule (hereinafter referred to as “ Specific rosin diol ").

In the general formula (1), R ¹ and R ² each independently represents hydrogen or a methyl group. L ¹ represents a chain alkylene group which may have a substituent, or a divalent group obtained by combining the chain alkylene group with an ester group or an ether group, and L ² and L ³ are each independently , A carbonyl group, an ester group, an ether group, a sulfonyl group, a chain alkylene group which may have a substituent, a cyclic alkylene group which may have a substituent, an arylene group which may have a substituent, and It represents a divalent linking group selected from the group consisting of divalent groups obtained by combining them, and L ¹ and L ² or L ¹ and L ³ may form a ring. A ¹ and A ² represent a rosin ester group.
Here, the rosin ester group refers to a residue obtained by removing a hydrogen atom from a carboxyl group contained in rosin.

Examples of the chain alkylene group represented by L ¹ include chain alkylene groups having 1 to 10 carbon atoms, and among them, those having a methyl group as a substituent are preferable.
L ¹ is preferably a divalent group in which a chain alkylene group and an ester group or an ether group are combined. Among these, as L ¹ , a divalent group in which a methylene group, an ether group, and an alkylene group having 2 to 8 carbon atoms in total are combined is preferable, and a methylene group, an ether group, and an alkylene having 2 to 5 carbon atoms in total. A divalent group obtained by combining groups is more preferable. In this preferred embodiment, two methylene groups are present and the two methylene groups are preferably present at both ends of L ¹ . Here, the total number of carbons means the total number of carbons including the carbon number of the substituent when having a substituent containing a carbon atom.

Specific examples of L ¹ include divalent groups having structures shown in the following 1 to 8. Note that n is an integer of 2 or more.
Among the divalent groups shown below, structures shown by 1, 2, 3, and 5 are preferable, and structures shown by 1 and 5 having a methyl group as a substituent are particularly preferable.

Examples of the chain alkylene group represented by L ² and L ³ include alkylene groups having 1 to 10 carbon atoms.
Examples of the cyclic alkylene group represented by L ² and L ³ include a cyclic alkylene group having 3 to 7 carbon atoms.
Examples of the arylene group represented by L ² and L ³ include a phenylene group, a naphthylene group, and an anthracene group.
L ² and L ³ are preferably a chain alkylene group, and more preferably a chain alkylene group having 1 to 2 carbon atoms.

  Examples of the substituent introduced into the chain alkylene group, cyclic alkylene group, and arylene group include an alkyl group having 1 to 8 carbon atoms, an aryl group, and the like, and a linear, branched, or cyclic alkyl group includes preferable. Specifically, methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, isopropyl group, isobutyl group, s-butyl group, t-butyl group, isopentyl group, neopentyl group 1-methylbutyl group, isohexyl group, 2-ethylhexyl group, 2-methylhexyl group, cyclopentyl group, cyclohexyl group, phenyl group and the like.

Next, a method for synthesizing the specific rosin diol represented by the general formula (1) will be specifically described.
The specific rosin diol represented by the general formula (1) is synthesized by a known method, for example, a reaction between an epoxy compound and rosin.
The epoxy compound that may be used in the present embodiment is a bifunctional epoxy compound containing two epoxy groups in one molecule, such as diglycidyl ether of an aliphatic diol so as to be L ¹ in the general formula (1). Is mentioned.

Thus, by synthesizing a specific rosin diol using a polyfunctional epoxy compound, for example, a specific polyester resin containing a repeating unit derived from the specific rosin diol can obtain a toner having further excellent chargeability. . This is because the reactivity of the epoxy compound is higher than the reactivity of general-purpose other functional alcohols, and thus the carboxylic acid having low reactivity possessed by rosin can be efficiently reacted. As a result, reverse reactions and side reactions are also suppressed.
This is because the reactivity of the epoxy compound is higher than the reactivity of general-purpose other functional alcohols, and thus the carboxylic acid having low reactivity possessed by rosin can be efficiently reacted. As a result, reverse reactions and side reactions are also suppressed.

Representative examples of diglycidyl ethers of aliphatic diols include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol as the aliphatic diol component, Examples include 1,6-hexanediol, neopentyl glycol, 1,9-nonanediol, diethylene glycol, triethylene glycol, polyethylene glycol, polypropylene glycol, and polytetramethylene glycol.
Among them, preferred are ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol, neopentyl glycol, diethylene glycol and the like.

  The said epoxy group containing compound is obtained by reaction of a diol component and an epihalohydrin, for example.

  The reaction between rosin and the bifunctional epoxy compound proceeds mainly by a ring-opening reaction between the carboxyl group of rosin and the epoxy group of the bifunctional epoxy compound. At that time, the reaction temperature is preferably higher than the melting temperature of both components and / or at a temperature at which uniform mixing is possible, and specifically, a range of 60 ° C. or higher and 200 ° C. or lower is common. In the reaction, a catalyst for promoting the ring-opening reaction of the epoxy group may be added.

  Examples of the catalyst include amines such as ethylenediamine, trimethylamine and 2-methylimidazole, quaternary ammonium salts such as triethylammonium bromide, triethylammonium chloride and butyltrimethylammonium chloride, and triphenylphosphine.

  The reaction is carried out in various ways. For example, in the case of a batch system, rosin and 2 are mixed at a predetermined ratio in a heatable flask equipped with a cooling tube, a stirrer, an inert gas inlet, a thermometer and the like. A functional epoxy compound is charged, heated and melted, and the reaction progress is traced by sampling the reactant appropriately. The degree of progress of the reaction is confirmed mainly by a decrease in the acid value. For example, the reaction is appropriately completed when reaching the end of the stoichiometric reaction or in the vicinity thereof.

  The reaction ratio between the rosin and the bifunctional epoxy compound is preferably such that the rosin is reacted in the range of 1.5 mol to 2.5 mol with respect to 1 mol of the bifunctional epoxy compound, and more preferably 1 mol of the bifunctional epoxy compound. More preferably, the rosin is reacted in the range of 1.8 mol to 2.2 mol, and most preferably in the range of 1.85 mol to 2.1 mol. If the amount of rosin is less than 1.5 mol, the epoxy group of the bifunctional epoxy compound will remain in the subsequent polyester production process, causing a sudden increase in molecular weight due to the action as a crosslinking agent, and there is a concern of gelation. . On the other hand, when the amount of rosin is more than 2.5 mol, unreacted rosin remains, which may cause deterioration of charging due to increase in acid value.

Next, the rosin in the specific rosin diol represented by the general formula (1) will be described.
Rosin is a general term for resin acids obtained from trees, and the main component is a substance derived from natural products including abietic acid, which is one of tricyclic diterpenes, and isomers thereof. Specific components include, for example, parastrinic acid, neoabietic acid, pimaric acid, dehydroabietic acid, isopimaric acid, sandaracopimalic acid in addition to abietic acid, and the rosin used in this embodiment is a mixture thereof. is there. Rosin is roughly classified into three types: tall rosin that uses pulp as raw material, gum rosin that uses raw pine oil as raw material, and wood rosin that uses pine stumps as raw material. Since rosin is easily available, at least one of gum rosin and tall rosin is preferred.

  These rosins are preferably purified, for example, from high-purity rosins, which are thought to be generated from peroxides of resin acids, or unsaponified substances contained in unpurified rosins. By removing it, purified rosin can be obtained. The purification method is not particularly limited, and various known purification methods are selected. Specifically, methods such as distillation, recrystallization, extraction and the like can be mentioned. Industrially, purification by distillation is preferably performed. The distillation is usually selected in consideration of the distillation time at a pressure of 200 ° C. or more and 300 ° C. or less and 6.67 kPa or less. The recrystallization is performed, for example, by dissolving unpurified rosin in a good solvent and then distilling off the solvent to obtain a concentrated solution, and adding a poor solvent to the solution. Good solvents include aromatic hydrocarbons such as benzene, toluene and xylene, chlorinated hydrocarbons such as chloroform, alcohols such as lower alcohols, ketones such as acetone, and acetates such as ethyl acetate. Examples of the poor solvent include hydrocarbon solvents such as n-hexane, n-heptane, cyclohexane, and isooctane. Extraction can be performed by, for example, converting an unpurified rosin into an alkaline aqueous solution using alkaline water, extracting an insoluble unsaponified product contained therein with an organic solvent, and then neutralizing the aqueous layer to purify the purified rosin. Is the way to get.

The rosin may be a disproportionated rosin. Disproportionated rosin is a rosin containing abietic acid as a main component heated at high temperature in the presence of a disproportionation catalyst to eliminate unstable conjugated double bonds in the molecule. A mixture of dehydroabietic acid and dihydroabietic acid.
Examples of the disproportionation catalyst include various known catalysts such as supported catalysts such as palladium carbon, rhodium carbon, and platinum carbon, metal powders such as nickel and platinum, iodides such as iodine and iron iodide, and phosphorus compounds. . The amount of the catalyst used is usually preferably 0.01% by mass or more and 5% by mass or less, more preferably 0.01% by mass or more and 1% by mass or less, and the reaction temperature is 100 ° C. or more and 300 ° C. or less with respect to rosin. It is preferably 150 ° C. or higher and 290 ° C. or lower. In addition, as a method for controlling the amount of dehydroabietic acid, for example, dehydroabietic acid isolated by a method of crystallizing from disproportionated rosin as an ethanolamine salt (J. Org. Chem., 31, 4246 (1996)) You may add so that it may become this range.

The rosin may be a hydrogenated rosin. The hydrogenated rosin includes, for example, tetrahydroabietic acid and dihydroabietic acid as main components, and is obtained by eliminating unstable conjugated double bonds in the molecule by a known hydrogenation reaction. The hydrogenation reaction is carried out by heating an unpurified rosin in the presence of a hydrogenation catalyst, usually under a hydrogen pressure of 10 Kg / cm ² or more and 200 Kg / cm ² or less, preferably 50 Kg / cm ² or more and 150 Kg / cm ² or less. . Examples of the hydrogenation catalyst include various known catalysts such as supported catalysts such as palladium carbon, rhodium carbon and platinum carbon, metal powders such as nickel and platinum, and iodides such as iodine and iron iodide. The amount of the catalyst used is usually 0.01% by mass or more and 5% by mass or less, preferably 0.01% by mass or more and 1.0% by mass or less with respect to rosin, and the reaction temperature is 100 ° C. or more and 300 ° C. or less. Preferably they are 150 degreeC or more and 290 degrees C or less.
These disproportionated rosin and hydrogenated rosin may be provided with the purification step before and after the disproportionation treatment or the hydrogenation treatment.

  The rosin may be a polymerized rosin obtained by polymerizing rosin, an unsaturated carboxylic acid-modified rosin obtained by adding an unsaturated carboxylic acid to rosin, or a phenol-modified rosin. Examples of the unsaturated carboxylic acid used for the preparation of the unsaturated carboxylic acid-modified rosin include maleic acid, maleic anhydride, fumaric acid, acrylic acid, methacrylic acid and the like. The unsaturated carboxylic acid-modified rosin is obtained by modifying an unsaturated carboxylic acid with about 1 part by mass or more and about 30 parts by mass or less with respect to 100 parts by mass of the raw material rosin.

Among rosins, purified rosin that has been purified, disproportionated rosin that has been disproportionated, or hydrogenated to obtain a uniform specific polyester resin with uniform reactivity and reduced residual monomers and side reactions It is preferable to use a treated hydrogenated rosin (also called a hydrogenated rosin). These may be used alone or in any mixture.
The homogeneous specific polyester resin has an advantage that the chargeability of the toner becomes easier to control.
Further, when these rosins are applied, the phase of the toner is further dissolved, and as a result, the uniformity of the image gloss at the time of low-temperature fixing at high speed and low-pressure fixing is more easily improved.

  Examples of the specific rosin diol represented by the general formula (1) are shown below, but this embodiment is not limited thereto.

  In the exemplary compound of the specific rosin diol, n represents an integer of 2 or more.

  In synthesizing the specific polyester resin, the content of the specific rosin diol in this embodiment is 5 mol% or more and 60 mol in the total polyhydric alcohol component from the viewpoint of achieving both fixability and chargeability when applied to the toner. % Or less, preferably 5 mol% or more and 40 mol% or less, more preferably 10 mol% or more and 35 mol% or less.

[(C) chain aliphatic polyhydric alcohol]
Then, (C) chain | strand-shaped aliphatic polyhydric alcohol which is one of the polyhydric alcohol components used in order to obtain specific polyester resin is demonstrated.
In this embodiment, in order to obtain a specific polyester resin, (C) a chain aliphatic polyhydric alcohol different from the above-mentioned (B) specific rosin diol is used in combination.

(C) A chain aliphatic polyhydric alcohol refers to a compound in which a plurality of alcoholic hydroxyl groups are linked by a chain aliphatic group. Among them, an aliphatic diol in which two alcoholic hydroxyl groups are connected by a chain aliphatic group is preferable.
The chain aliphatic group is preferably a chain alkylene group and may have a substituent such as an alkyl group. The chain aliphatic group is particularly preferably a chain alkylene group having 5 or less carbon atoms and including carbon atoms in the substituent.

Examples of the aliphatic diol include, for example, ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 2, 3-butanediol, 1,4-butenediol, 2-methyl-1,3-propanediol, 1,5-pentanediol, neopentyl glycol, 2-ethyl-2-methylpropane-1,3-diol, 2 -Butyl-2-ethylpropane-1,3-diol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, 2-ethyl-1,3-hexanediol, 2,4-dimethyl-1 , 5-pentanediol, 2,2,4-trimethyl-1,3-pentanediol, 1,7-heptanediol, 1,8-octanediol, 9-nonanediol, 1,10-decanediol, 3-hydroxy-2,2-dimethylpropyl-3-hydroxy-2,2-dimethylpropanoate, diethylene glycol, triethylene glycol, polyethylene glycol, dipropylene glycol, polypropylene Glycol and the like.
These aliphatic diols may be used alone or in combination of two or more.

  Among these, ethylene glycol, 1,2-propanediol, 1,3-propanediol, and neopentyl glycol are preferable from the viewpoint that the low-temperature fixability of the toner can be further improved when applied to the toner.

  In synthesizing the specific polyester resin, the content of the (C) chain aliphatic polyhydric alcohol is 10 mol% or more in the polyhydric alcohol component from the viewpoint of achieving both fixing property and chargeability when applied to the toner. 95 mol% or less is preferable and 15 mol% or more and 90 mol% or less are more preferable.

In the specific polyester resin according to the present embodiment, the total amount of (B) the polyhydric alcohol represented by the general formula (1) and (C) the chain aliphatic polyhydric alcohol is 60 mol% in the total alcohol components. The polycondensate is 100 mol% or less (preferably 70 mol% or more and 100 mol% or less, more preferably 80 mol% or more and 100 mol% or less).
By setting the content ratio, a polyester resin that can improve the low-temperature fixability of the toner when applied to the toner is obtained.

Furthermore, the specific polyester resin according to the present embodiment is (B) a molar ratio of (B) / (C)] a polyhydric alcohol represented by the general formula (1) / (C) a chain aliphatic polyhydric alcohol. Is a polycondensate having a molecular weight of 0.1 to 1.0 (preferably 0.2 to 0.5).
With this content ratio, a polyester resin that can improve the low-temperature fixability of the toner when applied to the toner is obtained.

[(D) Other polyhydric alcohols]
When obtaining the specific polyester resin according to the present embodiment, in addition to the polyhydric alcohol represented by (B) the general formula (1) and (C) the chain aliphatic polyhydric alcohol, For example, other polyhydric alcohols may be used.
Other polyhydric alcohols include etherified diphenols.
Etherified diphenol is a diol obtained by addition reaction of bisphenol A and alkylene oxide. The alkylene oxide is ethylene oxide or propylene oxide, and the average added mole number of alkylene oxide is 1 mol of bisphenol A. It is preferably 2 mol or more and 16 mol or less.

The specific polyester resin includes the polycondensate of (A) a polyvalent carboxylic acid component, (B) a polyhydric alcohol represented by the general formula (1), and (C) a chain aliphatic polyhydric alcohol, If necessary, (D) other polyhydric alcohol components can be used as raw materials to obtain by known and conventional polycondensation.
As the reaction method, either a transesterification reaction or a direct esterification reaction can be applied. Further, polycondensation may be promoted by a method of increasing the reaction temperature by pressurization, a method of reducing the pressure, or a method of flowing an inert gas under normal pressure. Depending on the reaction, a known and commonly used reaction catalyst such as at least one metal compound selected from antimony, titanium, tin, zinc, aluminum, manganese, and germanium may be used to accelerate the reaction. The addition amount of these reaction catalysts is preferably 0.01 parts by mass or more and 1.5 parts by mass or less, and more preferably 0.05 parts by mass or more and 1.0 parts by mass or less with respect to 100 parts by mass of the total amount of the acid component and alcohol component. preferable. The reaction temperature is preferably 180 ° C. or higher and 300 ° C. or lower.

  Since the rosin that is the base of the rosin ester group contained in the specific rosin diol has a bulky structure and high hydrophobicity, the specific polyester resin containing the rosin ester group is difficult to contain water. In addition, because of the structure of the specific polyester resin, a hydroxyl group or a carboxyl group is present only at the terminal of the resin molecule, so that the amount of the hydroxyl group or carboxyl group in the resin can be adversely affected to the chargeability of the toner. The amount of rosin ester groups can be increased. Furthermore, when the specific rosin diol is obtained by reacting rosin with a bifunctional epoxy compound, the ring opening reaction of the epoxy group occurring between the epoxy group in the bifunctional epoxy compound and the carboxyl group in the rosin is an alcohol component. Since the reactivity is higher than the esterification reaction that occurs between the rosin and the rosin, unreacted rosin hardly remains in the specific polyester resin.

  Below, an example of the synthetic scheme of specific polyester resin is shown. In the following synthesis scheme, a specific rosin diol is synthesized by reacting a bifunctional epoxy compound and rosin, and a polycondensate of a specific polyester resin is synthesized by dehydrating polycondensation of the specific rosin diol and dicarboxylic acid. The In the structural formula representing the specific polyester resin, a portion surrounded by a dotted line corresponds to a rosin ester group.

  In addition, when the polycondensate of a specific polyester resin is hydrolyzed, it is decomposed into the following monomers. Since the specific polyester resin is a 1: 1 condensate of a polyvalent carboxylic acid and a polyhydric alcohol, a constituent component of the resin is estimated from the decomposition product.

[Physical properties of specific polyester resin]
The softening temperature of the specific polyester resin according to this embodiment is preferably 80 ° C. or higher and 160 ° C. or lower, and preferably 90 ° C. or higher and 150 ° C. or lower, from the viewpoints of toner fixability, storage stability, and durability when applied to the toner. More preferred.
The glass transition temperature of the specific polyester resin according to the present embodiment is preferably 35 ° C. or more and 80 ° C. or less, and 40 ° C. from the viewpoint of toner fixability, storage stability, and durability when used as a toner binder resin. More preferably, it is 70 ° C. or lower.
The softening temperature and glass transition temperature can be easily adjusted by adjusting the raw material monomer composition, the polymerization initiator, the molecular weight, the catalyst amount, etc., or by selecting the reaction conditions.
Moreover, about the softening temperature and glass transition temperature of specific polyester resin, it calculates | requires by the method described in the Example.

The acid value of the specific polyester resin according to the exemplary embodiment is preferably 1 mgKOH / g or more and 50 mgKOH / g or less, and more preferably 3 mgKOH / g or more and 30 mgKOH / g or less from the viewpoint of chargeability of the toner when applied to the toner. .
Further, from the viewpoint of toner durability and hot offset resistance when applied to the toner, the weight average molecular weight (Mw) of the specific polyester resin according to this embodiment is preferably 4,000 or more and 1,000,000 or less, More preferably, it is 7,000 or more and 300,000 or less, and more preferably 20,000 or more and 90,000 or less.
In addition, the acid value of the specific polyester resin, the weight average molecular weight Mw, and the number average molecular weight Mn are calculated | required by the method described in the Example.

  The specific polyester resin according to this embodiment may be a modified polyester. Examples of the modified polyester include grafting and blocking with phenol, urethane, epoxy and the like by the methods described in JP-A-11-133668, JP-A-10-239903, JP-A-8-20636, and the like. Polyester.

<Toner for electrostatic image development>
The toner for developing an electrostatic charge image (hereinafter referred to as “toner”) according to the present embodiment contains the above-described specific polyester resin as a binder resin, and if necessary, a colorant, a release agent, and a charge control agent. , Including external additives and the like.
The toner according to the exemplary embodiment includes, in addition to the specific polyester resin, a known binder resin, for example, a polyester resin different from the specific polyester resin, styrene-acrylic, as long as the effects due to the specific polyester resin are not impaired. Other resins such as vinyl resin such as resin, epoxy resin, polycarbonate, polyurethane may be used in combination.
The content of the specific polyester resin in the binder resin constituting the toner is preferably 60% by mass or more, more preferably 80% by mass, and still more preferably 100% by mass.

(Coloring agent)
The colorant may be a dye or a pigment, but a pigment is desirable from the viewpoint of light resistance and water resistance.
Desirable colorants include carbon black, aniline black, aniline blue, calcoil blue, chrome yellow, ultramarine blue, dupont oil red, quinoline yellow, methylene blue chloride, phthalocyanine blue, malachite green oxalate, lamp black, rose bengal, Quinacridone, benzicine yellow, C.I. I. Pigment red 48: 1, C.I. I. Pigment red 57: 1, C.I. I. Pigment red 122, C.I. I. Pigment red 185, C.I. I. Pigment red 238, C.I. I. Pigment yellow 12, C.I. I. Pigment yellow 17, C.I. I. Pigment yellow 180, C.I. I. Pigment yellow 97, C.I. I. Pigment yellow 74, C.I. I. Pigment blue 15: 1, C.I. I. A known pigment such as CI Pigment Blue 15: 3 may be used.

As content of a coloring agent, the range of 1 to 30 mass parts is desirable with respect to 100 mass parts of binder resin. It is also effective to use a surface-treated colorant or a pigment dispersant as necessary.
By selecting the type of colorant, yellow toner, magenta toner, cyan toner, black toner and the like can be obtained.

(Release agent)
Examples of the release agent include paraffin wax such as low molecular weight polypropylene and low molecular weight polyethylene; silicone resin; rosins; rice wax; carnauba wax; The melting temperature of these release agents is preferably 50 ° C. or higher and 100 ° C. or lower, and more preferably 60 ° C. or higher and 95 ° C. or lower. The content of the release agent in the toner is desirably 0.5% by mass or more and 15% by mass or less, and more desirably 1.0% by mass or more and 12% by mass or less. When the content of the release agent is 0.5% by mass or more, the occurrence of defective peeling is prevented particularly in oilless fixing. When the content of the release agent is 15% by mass or less, the fluidity of the toner is not deteriorated, and the image quality and the reliability of image formation are improved.

(Charge control agent)
Known charge control agents may be used, but azo metal complex compounds, metal complex compounds of salicylic acid, and resin type charge control agents containing polar groups may be used.

(External additive)
The toner according to the exemplary embodiment may contain an inorganic powder as an external additive for toner particles for the purpose of improving fluidity.
Suitable inorganic powders include, for example, silica powder, alumina, titanium oxide, barium titanate, magnesium titanate, calcium titanate, strontium titanate, zinc oxide, silica sand, clay, mica, wollastonite, diatomaceous earth, Examples thereof include chromium oxide, cerium oxide, bengara, antimony trioxide, magnesium oxide, zirconium oxide, barium sulfate, barium carbonate, calcium carbonate, silicon carbide, and silicon nitride. Silica powder is particularly desirable. The proportion of the inorganic powder mixed with the toner is usually in the range of 0.01 to 5 parts by weight, preferably 0.01 to 2.0 parts by weight with respect to 100 parts by weight of the toner. Range. Moreover, you may use together well-known materials, such as a silica, titanium, a resin particle (resin particles, such as a polystyrene, PMMA, a melamine resin), and alumina, in this inorganic powder. Further, as a cleaning activator, a metal salt of a higher fatty acid typified by zinc stearate and particle powder of a fluorine-based high molecular weight substance may be added.

[Characteristics of toner]
The toner shape factor SF1 according to the exemplary embodiment is desirably in the range of 110 to 150, and more desirably in the range of 120 to 140.

Here, the shape factor SF1 is obtained by the following equation (1).
SF1 = (ML ² / A) × (π / 4) × 100 (1)
In the above formula (1), ML represents the absolute maximum length of the toner, and A represents the projected area of the toner.

  SF1 is quantified mainly by analyzing a microscope image or a scanning electron microscope (SEM) image using an image analyzer, and is calculated as follows, for example. That is, an optical microscope image of particles scattered on the surface of the slide glass is taken into a Luzex image analyzer through a video camera, and the maximum length and projected area of 100 particles are obtained, calculated by the above equation (1), and the average value is calculated. It is obtained by seeking.

  The volume average particle diameter of the toner according to the exemplary embodiment is preferably in the range of 4 μm to 15 μm, more preferably in the range of 4 μm to 10 μm, and still more preferably in the range of 4 μm to 8 μm.

  The volume average particle size is measured using a Coulter Multisizer (manufactured by Coulter Inc.) with an aperture diameter of 50 μm. At this time, the measurement was performed after the toner was dispersed in an electrolyte aqueous solution (Isoton aqueous solution) and dispersed by ultrasonic waves for 30 seconds or more.

[Toner Production Method]
The toner production method according to the exemplary embodiment is not particularly limited, and toner particles are produced by a known dry method such as a kneading and pulverizing method, a wet method such as an emulsion aggregation method or a suspension polymerization method, and the like. Thus, an external additive is externally added to the toner particles to obtain a toner.

The kneading and pulverizing method is a method for producing toner particles by kneading a kneaded product after kneading a toner forming material containing a binder resin to obtain a kneaded product.
More specifically, the kneading and pulverizing method is divided into a kneading step for kneading the toner forming material containing the binder resin and a pulverizing step for pulverizing the kneaded product. You may have other processes, such as a cooling process which cools the kneaded material formed by the kneading process as needed.
Each step will be described in detail.

-Kneading process-
In the kneading step, the toner forming material including the binder resin is kneaded.
In the kneading process, 0.5 to 5 parts by mass of an aqueous medium (for example, water such as distilled water or ion-exchanged water, alcohols, or the like) may be added to 100 parts by mass of the toner forming material. desirable.

  Examples of the kneader used in the kneading process include a single screw extruder, a twin screw extruder, and the like. Hereinafter, as an example of a kneading machine, a kneading machine having a feed screw part and two kneading parts will be described with reference to the drawings, but the invention is not limited thereto.

FIG. 1 is a diagram illustrating a screw state of an example of a screw extruder used in a kneading process in the toner manufacturing method according to the present embodiment.
The screw extruder 11 includes a barrel 12 having a screw (not shown), an inlet 14 for injecting a toner forming material as a raw material of the toner into the barrel 12, and an aqueous medium added to the toner forming material in the barrel 12. A liquid addition port 16 for discharging the toner, and a discharge port 18 for discharging the kneaded material formed by kneading the toner forming material in the barrel 12.

  The barrel 12 has a feed screw portion SA for transporting the toner forming material injected from the injection port 14 to the kneading portion NA in order from the side closer to the injection port 14, and the toner forming material is melt-kneaded by the first kneading process. A kneading part NA, a feed screw part SB for transporting the toner forming material melted and kneaded in the kneading part NA to the kneading part NB, and the toner forming material is melted and kneaded in a second kneading process. It is divided into a kneading part NB that forms the smelted product and a feed screw part SC that transports the formed kneaded product to the discharge port 18.

  The barrel 12 is provided with temperature control means (not shown) that is different for each block. That is, the temperature may be controlled at different temperatures from the block 12A to the block 12J. FIG. 1 shows a state in which the temperatures of the block 12A and the block 12B are controlled to t0 ° C., the temperatures of the blocks 12C to 12E are controlled to t1 ° C., and the temperatures of the blocks 12F to 12J are controlled to t2 ° C. ing. Therefore, the toner forming material of the kneading part NA is heated to t1 ° C., and the toner forming material of the kneading part NB is heated to t2 ° C.

  When the toner forming material containing the binder resin is supplied from the injection port 14 to the barrel 12, the toner forming material is sent to the kneading portion NA by the feed screw portion SA. At this time, since the temperature of the block 12C is set to t1 ° C., the toner forming material is fed into the kneading portion NA in a state of being heated and changed into a molten state. Since the temperatures of the block 12D and the block 12E are also set to t1 ° C., the toner forming material is melted and kneaded at the temperature of t1 ° C. in the kneading portion NA. The binder resin is in a molten state at the kneading portion NA and is subjected to shearing by the screw.

Next, the toner forming material that has been kneaded in the kneading part NA is sent to the kneading part NB by the feed screw part SB.
Next, the aqueous medium is added to the toner forming material by injecting the aqueous medium into the barrel 12 from the liquid addition port 16 in the feed screw portion SB. Moreover, although the form which inject | pours an aqueous medium in the feed screw part SB is shown in FIG. 1, it is not restricted to this, An aqueous medium may be inject | poured in the kneading part NB, The feed screw part SB and the kneading part NB In both cases, an aqueous medium may be injected. That is, the position and the injection location for injecting the aqueous medium are selected as necessary.

As described above, when the aqueous medium is injected into the barrel 12 from the liquid addition port 16, the toner forming material and the aqueous medium in the barrel 12 are mixed, and the toner forming material is cooled by the latent heat of vaporization of the aqueous medium. The temperature of the toner forming material is maintained appropriately.
Finally, the kneaded material formed by being melted and kneaded by the kneading part NB is transported to the discharge port 18 by the feed screw part SC and discharged from the discharge port 18.
As described above, the kneading process using the screw extruder 11 shown in FIG. 1 is performed.

-Cooling process-
The cooling step is a step of cooling the kneaded product formed in the kneading step. In the cooling step, the cooling temperature is 40 ° C. at an average temperature decrease rate of 4 ° C./sec or more from the temperature of the kneaded product at the end of the kneading step. It is preferable to cool to below. Rapid cooling at the above average cooling rate is preferable because the dispersion state immediately after the kneading process is maintained. In addition, the said average temperature-fall rate means the average value of the speed | rate to temperature-fall from the temperature of the kneaded material at the time of the completion | finish of a kneading process (for example, t2 degreeC when using the screw extruder 11 of FIG. 1) to 40 degreeC. .
Specific examples of the cooling method in the cooling step include a method using a rolling roll in which cold water or brine is circulated, a sandwiching cooling belt, and the like. When cooling is performed by the above method, the cooling rate is determined by the speed of the rolling roll, the flow rate of brine, the supply amount of the kneaded material, the slab thickness at the time of rolling the kneaded material, and the like. The slab thickness is preferably 1 to 3 mm.

-Crushing process-
The kneaded material cooled by the cooling process is pulverized by the pulverization process, and particles are formed. In the pulverization step, for example, a mechanical pulverizer or a jet pulverizer is used.

-Classification process-
The particles obtained by the pulverization step may be classified by a classification step in order to obtain toner particles having a volume average particle diameter in a target range, if necessary. In the classification process, conventionally used centrifugal classifiers, inertia classifiers, etc. are used, and fine powder (particles smaller than the target particle size) and coarse powder (target particle size). Larger particles) are removed.

-External addition process-
The obtained toner particles may be externally added with the above-described inorganic powder for the purpose of charge adjustment, fluidity provision, charge exchangeability and the like. These are performed by, for example, a V-type blender, a Henschel mixer, a Redige mixer, or the like, and are attached in stages.

-Sieving process-
You may provide a sieving process after the said external addition process as needed. Specific examples of the sieving method include a gyro shifter, a vibration sieving machine, and a wind sieving machine. By sieving, coarse particles of the external additive and the like are removed, and generation of streaks on the photosensitive member and scumming in the apparatus are suppressed.

In the toner according to the exemplary embodiment, the specific polyester resin is preferably present in the toner without unevenness. In order for the toner to take such a form, it is preferable to prepare the toner by a wet method such as an emulsion aggregation method or a suspension polymerization method.
The emulsion aggregation method includes an emulsification step of emulsifying the raw material constituting the toner to form resin particles (emulsion particles), an aggregation step of forming an aggregate containing the resin particles, and a fusion step of fusing the aggregates. You may have.
Specific steps are shown below.

-Emulsification process-
For example, the resin particle dispersion may be produced by applying a shearing force to a solution obtained by mixing an aqueous medium and a binder resin with a disperser. At that time, particles may be formed by heating to lower the viscosity of the resin component. A dispersant may be used for stabilizing the dispersed resin particles.
Furthermore, if the resin is oily and dissolves in a solvent having a relatively low solubility in water, the resin is dissolved in these solvents and dispersed in water together with a dispersant and a polymer electrolyte, and then heated or decompressed. By evaporating the solvent, a resin particle dispersion is produced.
Here, in preparing the resin particle dispersion, when a specific polyester resin used as a binder resin and a known binder resin are used in combination, one resin particle dispersion is prepared in a mixed state as described above. Alternatively, two resin particle dispersions containing different resins may be prepared and mixed in a subsequent aggregation step. The mixing conditions such as the mixing order are not particularly limited.

Examples of the aqueous medium include water such as distilled water and ion-exchanged water; alcohols; and the like. Water is preferable.
Examples of the dispersant used in the emulsification step include water-soluble polymers such as polyvinyl alcohol, methyl cellulose, ethyl cellulose, hydroxyethyl cellulose, carboxymethyl cellulose, sodium polyacrylate, and sodium polymethacrylate; sodium dodecylbenzenesulfonate, Anionic surfactants such as sodium octadecyl sulfate, sodium oleate, sodium laurate, potassium stearate, cationic surfactants such as laurylamine acetate, stearylamine acetate, lauryltrimethylammonium chloride, amphoteric such as lauryldimethylamine oxide Ionic surfactant, polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene Surfactants such as nonionic surfactants such as alkyl amines; and the like are; tricalcium phosphate, aluminum hydroxide, calcium sulfate, calcium carbonate, inorganic salts such as barium carbonate.

  Examples of the disperser used for preparing the emulsion include a homogenizer, a homomixer, a pressure kneader, an extruder, and a media disperser. As the size of the resin particles, the average particle diameter (volume average particle diameter) is preferably 1.0 μm or less, more preferably in the range of 60 nm to 300 nm, and further preferably in the range of 150 nm to 250 nm. . If it is less than 60 nm, the resin particles become stable particles in the dispersion, and thus aggregation of the resin particles may be difficult. On the other hand, if it exceeds 1.0 μm, the cohesiveness of the resin particles is improved and it becomes easy to prepare toner particles, but the particle size distribution of the toner may be widened.

  In preparing the release agent dispersion, the release agent is dispersed in water together with an ionic surfactant, a polymer electrolyte such as a polymer acid or a polymer base, and then heated to a temperature equal to or higher than the melting temperature of the release agent. Dispersion treatment is performed using a homogenizer or a pressure discharge type disperser to which a strong shearing force is applied while heating. Through the above treatment, a release agent dispersion is obtained. During the dispersion treatment, an inorganic compound such as polyaluminum chloride may be added to the dispersion. Examples of desirable inorganic compounds include polyaluminum chloride, aluminum sulfate, highly basic polyaluminum chloride (BAC), polyaluminum hydroxide, and aluminum chloride. Among these, polyaluminum chloride and aluminum sulfate are desirable. The release agent dispersion is used in the emulsion aggregation method, but the release agent dispersion may also be used when the toner is produced by suspension polymerization.

By the dispersion treatment, a release agent dispersion liquid containing release agent particles having a volume average particle diameter of 1 μm or less is obtained. In addition, the more preferable volume average particle diameter of the release agent particles is 100 nm or more and 500 nm or less.
When the volume average particle diameter is less than 100 nm, the properties of the binder resin used are affected, but generally the release agent component is hardly taken into the toner. On the other hand, if it exceeds 500 nm, the dispersion state of the release agent in the toner may be insufficient.

  For the preparation of the colorant dispersion, a known dispersion method can be used. For example, a general dispersion means such as a rotary shear type homogenizer, a ball mill having a medium, a sand mill, a dyno mill, or an optimizer can be employed. Is not to be done. The colorant is dispersed in water together with a polymer electrolyte such as an ionic surfactant, a polymer acid, or a polymer base. The volume average particle diameter of the dispersed colorant particles may be 1 μm or less, but if it is in the range of 80 nm or more and 500 nm or less, the dispersion of the colorant in the toner is preferable without impairing the cohesiveness.

-Aggregation process-
In the agglomeration step, a resin particle dispersion, a colorant dispersion, a release agent dispersion, etc. are mixed to form a mixed liquid, which is heated to agglomerate at a temperature lower than the glass transition temperature of the resin particles to form aggregated particles. To do. Aggregated particles are often formed by making the pH of the mixed solution acidic under stirring. The pH is preferably in the range of 2 to 7, and in this case, it is also effective to use a flocculant.
In the aggregation step, the release agent dispersion may be added and mixed at once with various dispersions such as a resin particle dispersion, or may be added in multiple portions.

  As the aggregating agent, a surfactant having a polarity opposite to that of the surfactant used for the dispersant, an inorganic metal salt, and a divalent or higher-valent metal complex are preferably used. In particular, the use of a metal complex is particularly desirable because the amount of the surfactant used can be reduced and the charging characteristics are improved.

  As the inorganic metal salt, an aluminum salt and a polymer thereof are particularly suitable. In order to obtain a narrower particle size distribution, the valence of the inorganic metal salt is bivalent than monovalent, trivalent than bivalent, trivalent than trivalent, and tetravalent than trivalent. Inorganic metal salt polymers are more suitable.

  Alternatively, a toner having a structure in which the surface of the core aggregated particles is coated with a resin may be prepared by additionally adding a resin particle dispersion when the aggregated particles have reached a desired particle size (coating step). In this case, the release agent and the colorant are not easily exposed on the toner surface, which is desirable from the viewpoint of chargeability and developability. In the case of additional addition, a flocculant may be added or pH adjustment may be performed before additional addition.

-Fusion process-
In the fusing step, the agglomeration is stopped by raising the pH of the suspension of the agglomerated particles to a range of 3 to 9 under stirring conditions according to the agglomeration step, and at a temperature equal to or higher than the glass transition temperature of the resin. The aggregated particles are fused by heating. Moreover, when it coat | covers with resin, this resin is also united and a core aggregated particle is coat | covered. The heating time may be as long as fusion is performed, and may be performed for about 0.5 hours to 10 hours.

Cool after fusion to obtain fused particles. Further, in the cooling step, crystallization may be promoted by reducing the cooling rate in the vicinity of the glass transition temperature (range of glass transition temperature ± 10 ° C.) of the resin, so-called slow cooling.
The fused particles obtained by fusing are made into toner particles through a solid-liquid separation process such as filtration and, if necessary, a washing process and a drying process. When no external additive is added to the toner particles, the obtained toner particles may be used as the toner.

-External addition process-
The inorganic particles described above may be externally added to the obtained toner particles in the same manner as in the kneading and pulverization method. The external addition method of the inorganic powder is the same as in the kneading and pulverization method.

<Electrostatic image developer>
The electrostatic image developer (hereinafter referred to as “developer”) according to this embodiment includes at least the toner according to this embodiment.
The toner according to the exemplary embodiment is used as it is as a one-component developer or as a two-component developer. When used as a two-component developer, it is used by mixing with a carrier.

  The carrier that can be used for the two-component developer is not particularly limited, and a known carrier may be used. Examples thereof include magnetic metals such as iron oxide, nickel and cobalt, magnetic oxides such as ferrite and magnetite, resin-coated carriers having a resin coating layer on the surface of the core material, and magnetic dispersion carriers. Further, a resin-dispersed carrier in which a conductive material or the like is dispersed in a matrix resin may be used.

  In the two-component developer, the mixing ratio (mass ratio) of the toner and the carrier is preferably in the range of toner: carrier = 1: 100 to 30: 100, and more preferably in the range of 3: 100 to 20: 100. .

<Image Forming Apparatus and Image Forming Method>
Next, an image forming apparatus according to this embodiment using the developer according to this embodiment will be described.
The image forming apparatus according to the present embodiment includes a latent image holding member, charging means for charging the surface of the latent image holding member, and electrostatic latent image forming for forming an electrostatic latent image on the surface of the latent image holding member. Means, a developer for storing the developer according to this embodiment in the electrostatic latent image, developing the electrostatic latent image with the developer to form a toner image, and transferring the toner image to a recording medium Transfer means for fixing, and fixing means for fixing the toner image on the recording medium.
By the image forming apparatus according to the present embodiment, a charging process for charging the surface of the latent image holding body, an electrostatic latent image forming process for forming an electrostatic latent image on the surface of the latent image holding body, and the electrostatic latent image A developing step of developing the image with the developer according to the present embodiment to form a toner image, a transfer step of transferring the toner image to a recording medium, and a fixing step of fixing the toner image on the recording medium. The image forming method according to the present embodiment is performed.

  In this image forming apparatus, for example, the part including the developing unit may be a cartridge structure (process cartridge) that can be attached to and detached from the main body of the image forming apparatus. The process cartridge includes a developing unit that stores the developer according to the exemplary embodiment and develops the electrostatic latent image formed on the surface of the latent image holding member with the developer to form a toner image. A process cartridge according to this embodiment that is detachably attached to the forming apparatus is preferably used.

Hereinafter, an example of the image forming apparatus according to the present embodiment will be described, but the present embodiment is not limited to this. In addition, the main part shown to a figure is demonstrated and the description is abbreviate | omitted about others.
FIG. 2 is a schematic configuration diagram showing a four-tandem color image forming apparatus. The image forming apparatus shown in FIG. 2 is a first to first electrophotographic method that outputs yellow (Y), magenta (M), cyan (C), and black (K) images based on color-separated image data. Fourth image forming units 10Y, 10M, 10C, and 10K (image forming means) are provided. These image forming units (hereinafter sometimes simply referred to as “units”) 10Y, 10M, 10C, and 10K are arranged in parallel in the horizontal direction at a predetermined distance from each other. The units 10Y, 10M, 10C, and 10K may be process cartridges that can be attached to and detached from the image forming apparatus main body.

Above each unit 10Y, 10M, 10C, 10K in the figure, an intermediate transfer belt 20 as an intermediate transfer member is extended through each unit. The intermediate transfer belt 20 is wound around a drive roller 22 and a support roller 24 that are in contact with the inner surface of the intermediate transfer belt 20, and travels in a direction from the first unit 10Y to the fourth unit 10K. The support roller 24 is urged away from the drive roller 22 by a spring or the like (not shown), and a predetermined tension is applied to the intermediate transfer belt 20 wound around the support roller 24. An intermediate transfer member cleaning device 30 is provided on the side surface of the latent image holding member of the intermediate transfer belt 20 so as to face the drive roller 22.
Further, each of the developing devices (developing means) 4Y, 4M, 4C, and 4K of the units 10Y, 10M, 10C, and 10K includes yellow, magenta, cyan, and black contained in the toner cartridges 8Y, 8M, 8C, and 8K. The four color toners can be supplied.

  Since the first to fourth units 10Y, 10M, 10C, and 10K described above have the same configuration, here, the first unit that forms a yellow image disposed on the upstream side in the intermediate transfer belt traveling direction. 10Y will be described as a representative. It should be noted that the second to fourth units are denoted by adding reference numerals with magenta (M), cyan (C), and black (K) instead of yellow (Y) to the same parts as the first unit 10Y. Description of 10M, 10C, 10K is omitted.

The first unit 10Y has a photoreceptor 1Y that functions as a latent image holding member. Around the photoreceptor 1Y, an electrostatic latent image is obtained by exposing the surface of the photoreceptor 1Y to a predetermined potential with a charging roller 2Y, and exposing the charged surface with a laser beam 3Y based on the color-separated image signal. An exposure device 3 for forming the electrostatic latent image, a developing device (developing means) 4Y for supplying the charged toner to the electrostatic latent image to develop the electrostatic latent image, and a primary transfer for transferring the developed toner image onto the intermediate transfer belt 20 A roller (primary transfer unit) 5Y and a photoconductor cleaning device (cleaning unit) 6Y for removing toner remaining on the surface of the photoconductor 1Y after the primary transfer are sequentially arranged.
The primary transfer roller 5Y is disposed inside the intermediate transfer belt 20 and is provided at a position facing the photoreceptor 1Y. Further, a bias power source (not shown) for applying a primary transfer bias is connected to each of the primary transfer rollers 5Y, 5M, 5C, and 5K. Each bias power source varies the transfer bias applied to each primary transfer roller under the control of a control unit (not shown).

Hereinafter, an operation of forming a yellow image in the first unit 10Y will be described. First, prior to the operation, the surface of the photoreceptor 1Y is charged to a potential of about −600V to −800V by the charging roller 2Y.
The photoreceptor 1Y is formed by laminating a photosensitive layer on a conductive substrate (volume resistivity at 20 ° C .: 1 × 10 ⁻⁶ Ωcm or less). This photosensitive layer usually has a high resistance (a resistance equivalent to that of a general resin), but has a property that the specific resistance of the portion irradiated with the laser beam changes when irradiated with the laser beam 3Y. Therefore, a laser beam 3Y is output to the surface of the charged photoreceptor 1Y via the exposure device 3 in accordance with yellow image data sent from a control unit (not shown). The laser beam 3Y is applied to the photosensitive layer on the surface of the photoreceptor 1Y, whereby an electrostatic latent image of a yellow print pattern is formed on the surface of the photoreceptor 1Y.

The electrostatic latent image is an image formed on the surface of the photoreceptor 1Y by charging. The specific resistance of the irradiated portion of the photosensitive layer is lowered by the laser beam 3Y, and the charged charge on the surface of the photoreceptor 1Y flows. On the other hand, this is a so-called negative latent image formed by the charge remaining in the portion not irradiated with the laser beam 3Y.
The electrostatic latent image formed on the photoreceptor 1Y in this way is rotated to a predetermined development position as the photoreceptor 1Y travels. Then, at this development position, the electrostatic latent image on the photoreceptor 1Y is converted into a visible image (developed image) by the developing device 4Y.

  The yellow developer stored in the developing device 4Y is triboelectrically charged by being stirred inside the developing device 4Y, and has the same polarity (negative polarity) as the charged electric charge on the photoreceptor 1Y. Is held on a developer roll (developer holder). As the surface of the photoreceptor 1Y passes through the developing device 4Y, the yellow toner is electrostatically attached to the latent image portion on the surface of the photoreceptor 1Y, and the latent image is developed with the yellow toner. . The photoreceptor 1Y on which the yellow toner image is formed continues to run at a predetermined speed, and the toner image developed on the photoreceptor 1Y is conveyed to a predetermined primary transfer position.

When the yellow toner image on the photoreceptor 1Y is conveyed to the primary transfer position, a predetermined primary transfer bias is applied to the primary transfer roller 5Y, and electrostatic force directed from the photoreceptor 1Y to the primary transfer roller 5Y. Acts on the toner image, and the toner image on the photoreceptor 1 </ b> Y is transferred onto the intermediate transfer belt 20. The transfer bias applied at this time has a polarity (+) opposite to the polarity (−) of the toner. For example, in the first unit 10Y, it is controlled to about +10 μA by a control unit (not shown).
On the other hand, the toner remaining on the photoreceptor 1Y is removed and collected by the photoreceptor cleaning device 6Y.

Further, the primary transfer bias applied to the primary transfer rollers 5M, 5C, and 5K after the second unit 10M is also controlled according to the first unit.
Thus, the intermediate transfer belt 20 to which the yellow toner image is transferred by the first unit 10Y is sequentially conveyed through the second to fourth units 10M, 10C, and 10K, and the toner images of the respective colors are superimposed to form a superimposed toner image. It is formed.

  The intermediate transfer belt 20 on which the four color toner images are superimposed through the first to fourth units is disposed on the image transfer surface side of the intermediate transfer belt 20, the support roller 24 in contact with the inner surface of the intermediate transfer belt 20, and the intermediate transfer belt 20. The secondary transfer roller (secondary transfer means) 26 is connected to a secondary transfer portion. On the other hand, a recording sheet (recording medium) P is fed at a predetermined timing to a gap where the secondary transfer roller 26 and the intermediate transfer belt 20 are pressed against each other via a supply mechanism, and a predetermined secondary transfer is performed. A bias is applied to the support roller 24. The transfer bias applied at this time has the same polarity (−) as the polarity (−) of the toner, and an electrostatic force from the intermediate transfer belt 20 toward the recording paper P is applied to the superimposed toner image, and the intermediate transfer belt. The superimposed toner image 20 is transferred onto the recording paper P. The secondary transfer bias at this time is determined according to the resistance detected by a resistance detection means (not shown) for detecting the resistance of the secondary transfer portion, and is voltage-controlled.

Thereafter, the recording paper P is sent to a fixing device (fixing means) 28, where the superimposed toner image is heated, and the color-superposed toner image is melted and fixed on the recording paper P. The recording paper P on which the fixing of the color image has been completed is conveyed by a conveyance roll (discharge roll) 32 toward the discharge unit, and a series of color image forming operations is completed.
The image forming apparatus exemplified above is configured to transfer the superimposed toner image onto the recording paper P via the intermediate transfer belt 20, but is not limited to this configuration, and is not limited to this configuration. A structure in which an image is transferred to a recording sheet may be used.

<Process cartridge, toner cartridge>
FIG. 3 is a schematic configuration diagram illustrating a preferred example of a process cartridge that stores the developer according to the present embodiment. The process cartridge 200 includes, together with the photoconductor 107, a charging device 108, a developing device 111, a photoconductor cleaning device (cleaning means) 113, an opening 118 for exposure, and an opening 117 for static elimination exposure. Are combined and integrated with each other.
The process cartridge 200 is detachable from an image forming apparatus main body including a transfer device 112, a fixing device 115, and other components not shown. It constitutes. Reference numeral 300 denotes a recording sheet.

  The process cartridge 200 shown in FIG. 3 includes a photoconductor 107, a charging device 108, a developing device 111, a photoconductor cleaning device 113, an opening 118 for exposure, and an opening 117 for static elimination exposure. These devices may be selectively combined. In the process cartridge according to the present embodiment, in addition to the developing device 111, the photoconductor 107, the charging device 108, the photoconductor cleaning device (cleaning means) 113, the opening 118 for exposure, and the charge removal exposure. You may provide at least 1 sort (s) selected from the group comprised from the opening part 117. FIG.

Next, the toner cartridge will be described.
The toner cartridge is detachably attached to the image forming apparatus, and at least in the toner cartridge that stores toner to be supplied to the developing means provided in the image forming apparatus, the toner is in the above-described embodiment. Such toner is used. The toner cartridge only needs to contain at least toner, and may contain developer, for example, depending on the mechanism of the image forming apparatus.

  2 is an image forming apparatus having a configuration in which the toner cartridges 8Y, 8M, 8C, and 8K can be attached and detached, and the developing devices 4Y, 4M, 4C, and 4K are respectively the developing devices ( Are connected to a toner cartridge corresponding to (color) by a developer supply pipe (not shown). When the amount of developer stored in the toner cartridge is low, the toner cartridge is replaced.

  Hereinafter, although an example is given and this embodiment is explained concretely, this embodiment is not limited only to an example shown below. In the examples, “parts” and “%” mean “parts by mass” and “% by mass” unless otherwise specified.

[Measurement methods for various physical properties]
<Measurement of acid value>
The acid value was measured according to JIS K0070 and using a neutralization titration method. That is, an appropriate amount of a sample is taken, 100 ml of a solvent (diethyl ether / ethanol mixed solution) and a few drops of an indicator (phenolphthalein solution) are added, and shaken sufficiently until the sample is completely dissolved in a water bath. This was titrated with a 0.1 mol / l potassium hydroxide ethanol solution, and the end point was when the indicator was light red for 30 seconds. When the acid value is A, the sample amount is S (g), the 0.1 mol / l potassium hydroxide ethanol solution used for the titration is B (ml), and f is the factor of the 0.1 mol / l potassium hydroxide ethanol solution. , A = (B × f × 5.611) / S.

<Measurement of weight average molecular weight Mw and number average molecular weight Mn>
Two “HLC-8120GPC, SC-8020 (6.0 mm ID × 15 cm) manufactured by Tosoh Corporation” were used, and THF (tetrahydrofuran) was used as an eluent. As experimental conditions, the experiment was conducted 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 RI detector. The calibration curve is “Polystyrene 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 ".

<Measurement of glass transition temperature>
Using “DSC-20” (manufactured by Seiko Denshi Kogyo Co., Ltd.), 10 mg of a sample was heated at a constant temperature increase rate (10 ° C./min) and measured.

<Measurement of softening temperature>
The softening temperature is measured using a Koka-type flow tester CFT-500 (manufactured by Shimadzu Corporation), the diameter of the fine pores of the die is 0.5 mm, the pressure load is 0.98 MPa (10 Kg / cm ² ), and the temperature is raised. The temperature was determined as a temperature corresponding to ½ of the height from the outflow start point to the end point when a sample of 1 cm ³ was melted out under a condition where the speed was 1 ° C./min.

[Synthesis Example 1]
-Synthesis of Rosindiol 1 (Exemplary Compound (10))-
100 parts by mass of neopentyl glycol diglycidyl (reagent, manufactured by Tokyo Chemical Industry Co., Ltd.) as a bifunctional epoxy compound, 200 parts by mass of disproportionated rosin (trade name: InCrystal KR614, manufactured by Arakawa Chemical Industries, Ltd.), and As a reaction catalyst, 0.2 part by mass of tetraethylammonium bromide (manufactured by Tokyo Chemical Industry Co., Ltd.) is charged into a stainless steel reaction vessel equipped with a stirrer, a heating device, a cooling tube, and a thermometer, and the temperature is raised to 130 ° C. A ring-opening reaction between the acid group of rosin and the epoxy group of the epoxy compound was performed.
The reaction was continued at the same temperature for 4 hours, and when the acid value reached 0.5 mg KOH / g, the reaction was stopped to obtain rosin diol 1.

[Synthesis Example 2]
-Synthesis of Rosindiol 2 (Exemplary Compound (16))-
100 parts by mass of neopentyl glycol diglycidyl (reagent, manufactured by Tokyo Chemical Industry Co., Ltd.) as a bifunctional epoxy compound, 205 parts by mass of hydrogenated rosin (trade name: Hyper CH, manufactured by Arakawa Chemical Industries, Ltd.) as a rosin component, In addition, 0.4 parts by mass of tetraethylammonium bromide (manufactured by Tokyo Chemical Industry Co., Ltd.) as a reaction catalyst was charged into a stainless steel reaction vessel equipped with a stirrer, a heating device, a cooling tube, and a thermometer, and the temperature was raised to 130 ° C. The ring-opening reaction between the acid group of rosin and the epoxy group of the epoxy compound was carried out.
The reaction was continued at the same temperature for 4 hours, and when the acid value reached 0.5 mg KOH / g, the reaction was stopped to obtain rosin diol 2.

[Synthesis Example 3]
—Synthesis of Rosindiol 3 (Exemplary Compound (4)) —
100 parts by mass of neopentylglycol diglycidyl (reagent, manufactured by Tokyo Chemical Industry Co., Ltd.) as a bifunctional epoxy compound, 200 parts by mass of purified rosin (trade name: Pine Crystal KR65, manufactured by Arakawa Chemical Industries, Ltd.) as a rosin component, and As a reaction catalyst, 0.4 parts by mass of tetraethylammonium bromide (manufactured by Tokyo Chemical Industry Co., Ltd.) was charged into a stainless steel reaction vessel equipped with a stirrer, a heating device, a cooling tube, and a thermometer, and the temperature was raised to 130 ° C. A ring-opening reaction between the acid group of rosin and the epoxy group of the epoxy compound was performed.
The reaction was continued for 4 hours at the same temperature, and when the acid value reached 0.5 mgKOH / g, the reaction was stopped to obtain rosindiol 3.

[Synthesis Example 4]
—Synthesis of Rosindiol 4 (Exemplary Compound (15)) —
80 parts by mass of ethylene glycol diglycidyl (reagent, manufactured by Tokyo Chemical Industry Co., Ltd.) as a bifunctional epoxy compound, 200 parts by mass of hydrogenated rosin (trade name: High Pale CH, manufactured by Arakawa Chemical Industries, Ltd.) as the rosin component, and As a reaction catalyst, 0.2 part by mass of tetraethylammonium bromide (manufactured by Tokyo Chemical Industry Co., Ltd.) is charged into a stainless steel reaction vessel equipped with a stirrer, a heating device, a cooling tube, and a thermometer, and the temperature is raised to 130 ° C. A ring-opening reaction between the acid group of rosin and the epoxy group of the epoxy compound was performed.
The reaction was continued at the same temperature for 4 hours, and when the acid value reached 0.5 mg KOH / g, the reaction was stopped to obtain rosin diol 4.

[Synthesis Example 5]
—Synthesis of Rosindiol 5 (Exemplary Compound (2)) —
90 parts by mass of propylene glycol diglycidyl (reagent, manufactured by Wako Pure Chemical Industries, Ltd.) as a bifunctional epoxy compound, 200 parts by mass of purified rosin (trade name: Pine Crystal KR65 Arakawa Chemical Industries, Ltd.) as a rosin component, and reaction As a catalyst, 0.4 parts by mass of tetraethylammonium bromide (manufactured by Tokyo Chemical Industry Co., Ltd.) was charged into a stainless steel reaction vessel equipped with a stirrer, a heating device, a cooling pipe, and a thermometer, and the temperature was raised to 130 ° C. A ring-opening reaction between the acid group of rosin and the epoxy group of the epoxy compound was performed.
The reaction was continued at the same temperature for 4 hours, and when the acid value reached 0.5 mgKOH / g, the reaction was stopped to obtain rosin diol 5.

[Synthesis Example 6]
-Synthesis of rosindiol 6 (comparative rosindiol)-
115 parts by mass of bisphenol A diglycidyl (reagent, manufactured by Tokyo Chemical Industry Co., Ltd.) as a bifunctional epoxy compound, 200 parts by mass of disproportionated rosin (trade name: Pine Crystal KR614, manufactured by Arakawa Chemical Industries) as a rosin component, and reaction catalyst Of tetraethylammonium bromide (manufactured by Tokyo Chemical Industry Co., Ltd.) in a stainless steel reaction vessel equipped with a stirrer, a heating device, a cooling tube and a thermometer, raising the temperature to 130 ° C., A ring-opening reaction between the acid group and the epoxy group of the epoxy compound was performed.
The reaction was continued at the same temperature for 4 hours, and when the acid value reached 0.5 mg KOH / g, the reaction was stopped to obtain rosin diol 6.

[Synthesis Example 7]
-Synthesis of rosindiol 7 (comparative rosindiol)-
105 parts by mass of diglycidyl terephthalate (trade name: Denacol EX711, manufactured by Nagase ChemteX Corp.) as a bifunctional epoxy compound, and 200 parts by mass of hydrogenated rosin (trade name: Hyper CH, manufactured by Arakawa Chemical Industries, Ltd.) as a rosin component , And 0.4 parts by mass of tetraethylammonium bromide (manufactured by Tokyo Chemical Industry Co., Ltd.) as a reaction catalyst were charged into a stainless steel reaction vessel equipped with a stirrer, a heating device, a cooling tube, and a thermometer, and the temperature was raised to 130 ° C. The ring-opening reaction between the acid group of rosin and the epoxy group of the epoxy compound was carried out.
The reaction was continued at the same temperature for 4 hours, and when the acid value reached 0.5 mg KOH / g, the reaction was stopped to obtain rosin diol 7.

[Synthesis Example A]
-Synthesis of specific polyester resin 1-
A stirrer containing 85 g of terephthalic acid (TPA) as the polyvalent carboxylic acid component, 1:60 g of rosin diol as the polyhydric alcohol component, 40 g of neopentyl glycol, and 0.1 g of tetra-n-butyl titanate as the reaction catalyst , Charged in a stainless steel reaction vessel equipped with a heating device, thermometer, fractionation device, and nitrogen gas inlet tube, and subjected to a polycondensation reaction at 230 ° C. for 9 hours with stirring in a nitrogen atmosphere to obtain a predetermined molecular weight and acid value. After confirming that the specific polyester resin 1 was reached, a specific polyester resin 1 was synthesized.
About the obtained rosin resin 1, the weight average molecular weight Mw and the number average molecular weight Mn, the acid value, and the glass transition temperature were measured by the above-mentioned method, and the measurement result was described in Table 1.

[Synthesis Examples B to P]
In the same manner as the synthesis of the specific polyester resin 1 in Synthesis Example A, using the monomer components described in Table 1 below in the content ratio (molar ratio) described in Table 1 below, the specific polyester resins 2 to 11 and Comparative polyester resins C1 to C5 were synthesized.
About the obtained polyester resin, the weight average molecular weight Mw and the number average molecular weight Mn, the acid value, and the glass transition temperature were measured by the above-mentioned method, and the measurement result was written together in Table 1.

Abbreviations in Table 1 are shown below.
EG: ethylene glycol PG: propylene glycol 13PD: 1,3-propanediol NPG: neopentyl glycol bisphenol A propylene oxide adduct TPA: terephthalic acid IPA: isophthalic acid

<Preparation of Toner 1>
[Preparation of resin particle dispersion 1]
(Preparation of polyester resin particle dispersion 1)
Specific polyester resin 1: 100 parts by mass was charged into a reactor equipped with a stirrer, dissolved and mixed at 120 ° C. for 30 minutes, and then mixed with 800 parts by mass of ion-exchanged water heated to 95 ° C., 1.0 mg of sodium dodecylbenzenesulfonate. An aqueous solution for neutralization in which 1.0 part by mass of 1 part by weight of 1N NaOH aqueous solution was put into a flask, emulsified with a homogenizer (Ultra Turrax, manufactured by IKA) for 5 minutes, and further 10 minutes in an ultrasonic bath. After shaking, the flask was cooled with room temperature water. As a result, a resin particle dispersion A1 having a median diameter of resin particles of 250 nm and a solid content of 20% by mass was obtained.

[Preparation of Colorant Particle Dispersion 1]
Cyan pigment: 50 parts by mass (manufactured by Dainichi Seika Kogyo Co., Ltd., copper phthalocyanine, CI Pigment Blue 15: 3)
Anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd., Neogen R): 5 parts by mass Ion-exchanged water: 200 parts by mass The above components are mixed and dissolved, and a homogenizer (IKA, Ultra Tarrax) 5 minutes And an ultrasonic bath for 10 minutes to obtain a Sian colorant particle dispersion 1 having a center diameter of 190 nm and a solid content of 21.5%.

[Preparation of release agent particle dispersion 1]
-Anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd., Neogen R): 2 parts by mass-Ion exchange water: 800 parts by mass-Paraffin wax (HNP-9 manufactured by Nippon Seiki Co., Ltd.): 200 parts by mass The mixture was heated to 120 ° C. and dispersed with a pressure discharge type gorin homogenizer to obtain a 20% by mass release agent dispersion having a volume average particle size of 170 nm.

-Preparation of toner-
Polyester resin particle dispersion 1 (high molecular weight resin particle dispersion): 100 parts by weight Colorant dispersion 1: 62 parts by weight Anionic surfactant (20% aqueous solution of Dowfax2A1): 15 parts by weight Release agent dispersion Liquid 1:77 parts by mass First, in a polymerization kettle equipped with a pH meter, a stirring blade, and a thermometer, among the above raw materials, polyester resin particle dispersion 1, an anionic surfactant, and 250 parts by mass of ion-exchanged water are added. The surfactant was blended with the polyester resin particle dispersion while stirring at 130 rpm for 15 minutes. Colorant dispersion 1 and release agent dispersion 1 were added and mixed with this, and then a 0.3 M nitric acid aqueous solution was added to the raw material mixture to adjust the pH to 4.8. Subsequently, 13 parts by mass of a 10% nitric acid aqueous solution of aluminum sulfate as a flocculant was dropped while applying a shearing force at 3000 rpm with an ultra turrax. Since the viscosity of the raw material mixture increased during the dropping of the flocculant, when the viscosity increased, the dropping speed was slowed so that the flocculant was not biased to one place. When the dropping of the flocculant was completed, the rotation speed was further increased to 5000 rpm, and the mixture was stirred for 5 minutes to sufficiently mix the flocculant and the raw material mixture.

  Subsequently, the raw material mixture was stirred at 500 rpm while being heated to 25 ° C. with a mantle heater. After stirring for 10 minutes, it was confirmed that a primary particle size was formed using a Coulter Multisizer II (aperture diameter: 50 μm; manufactured by Coulter, Inc.), and then 43 ° C. at 0.1 ° C./min for growing aggregated particles. The temperature was raised to. The growth of aggregated particles is confirmed at any time using a Coulter Multisizer. Depending on the aggregation rate, the aggregation temperature and the number of rotations of stirring were changed.

  On the other hand, for covering the aggregated particles, the polyester resin particle dispersion 1 is mixed with 160 parts by mass of 118 parts by mass of ion-exchanged water and 8.2 parts by mass of an anionic surfactant (20% aqueous solution of Dowfax2A1). The pH was adjusted to 3.8 in advance to obtain a coating resin particle dispersion. When the aggregated particles grew to 5.2 μm in the aggregation step, a coating resin particle dispersion prepared in advance was added and held for 20 minutes with stirring. Thereafter, in order to stop the growth of the coated aggregated particles, 1.5 pph of EDTA was added, and then a 1M sodium hydroxide aqueous solution was added to control the pH of the raw material mixture to 7.6. Subsequently, in order to fuse the aggregated particles, the temperature was raised to 85 ° C. at a temperature raising rate of 1 ° C./min while adjusting the pH to 7.6. After reaching 85 ° C., the pH is adjusted to 7.6 or less in order to proceed with the fusion, and after confirming that the aggregated particles have fused with an optical microscope, ice water is used to stop the growth of the particle size. Was injected and quenched at a temperature lowering rate of 10 ° C./min.

Subsequently, the obtained particles were sieved once with a 15 μm mesh for the purpose of washing. Thereafter, approximately 10 times the amount of ion-exchanged water (30 ° C.) was added to the solid content, stirred for 20 minutes, and then once filtered. Further, the solid content remaining on the filter paper was dispersed in a slurry, repeatedly washed with ion exchange water at 30 ° C. four times, and dried to obtain toner particles 1 having a volume average particle diameter of 6.1 μm.
The volume average particle size distribution index GSDv of the toner 1 (toner particles 1) is 1.23, and the shape factor SF1 of the toner particles determined by shape observation with Luzex is 128.

<Preparation of Developer 1>
Using the obtained toner 1, developer 1 was produced as follows.
To 50 parts by mass of toner, 1.5 parts by mass of hydrophobic silica (manufactured by Cabot, TS720) was added and mixed by a sample mill to obtain externally added toner 1.
Further, as a carrier, a ferrite carrier having an average particle diameter of 35 μm coated with 1% by mass of polymethyl methacrylate resin (Mw: 80000, manufactured by Soken Chemical Co., Ltd.) is used, and externally added so that the toner concentration becomes 5% by mass. Toner 1 was weighed, and both were stirred and mixed in a ball mill for 5 minutes to prepare Developer 1.

<Production of developers 2 to 11 and C1 to C5>
(Preparation of polyester resin particle dispersions 2-11, C1-C5)
First, in place of the specific polyester resin 1, the polyester resin particle dispersions 2 to 11 are the same as the polyester resin particle dispersion 1, except that the specific polyester resins 2 to 11 or comparative polyester resins C1 to C5 are used. C1 to C5 were prepared.

  Subsequently, toners 2 to 11 and C1 to C5 were produced in the same manner as the toner 1 except that a resin particle dispersion of a resin type according to Table 1 was used instead of the polyester resin dispersion 1. Developers 2 to 11 and C1 to C5 were prepared in the same manner as Developer 1 except that these toners 2 to 11 and C1 to C5 were used.

[Evaluation]
Each developer thus obtained was evaluated as follows. The results are shown in Table 2.

-Evaluation of low-temperature fixability-
A solid image is formed on each copy of the developer obtained on Fuji Xerox copy paper (J paper) to a toner amount of 0.9 mg / cm 2, using a Color Document-60 (Fuji Xerox Co., Ltd.) remodeling machine. The image was fixed at a nip width of 6.5 mm and a fixing speed of 220 mm / sec, and the low-temperature fixability was evaluated. In the evaluation, the fixing device temperature was changed every 10 ° C. from 100 ° C. to 200 ° C., and a fixed image was prepared at each fixing temperature, and then a certain fruit juice was applied to the image surface of each obtained fixed image. By rubbing with folding gauze, the degree of peeling of the image at the fold portion was observed, and the width of the paper appearing at the fold portion as a result of peeling the image was measured. The fixing temperature at which the width was 0.5 mm or less was defined as MFT (minimum fixing temperature, ° C.). The evaluation criteria are as follows.
-Evaluation criteria-
A: MFT is 120 ° C. or lower and exhibits low-temperature fixability.
B: MFT is over 120 ° C. and not more than 125 ° C., which is slightly inferior to A in low temperature fixability.
C: MFT is more than 125 ° C. and not more than 130 ° C., which is inferior to A in low temperature fixability.
D: MFT is over 130 ° C. and below 135 ° C., and the low temperature fixability is poor.
-E: MFT exceeds 135 degreeC and does not have low temperature fixability.

-Evaluation of fixing temperature range-
The hot offset occurrence temperature was measured using the same solit image as that of the apparatus. In the evaluation, the temperature was raised stepwise and the lowest temperature at which hot offset occurred was measured. The fixing temperature range was evaluated from the difference between the hot offset occurrence temperature and the minimum fixing temperature.
-Evaluation criteria-
A: The difference between the minimum fixing temperature and the hot offset occurrence temperature is 95 ° C. or more. B: The difference between the minimum fixing temperature and the hot offset occurrence temperature is 90 ° C. or more and less than 95 ° C. C: The minimum fixing temperature and the hot offset occurrence temperature The difference between the minimum fixing temperature and the hot offset occurrence temperature is 65 ° C. or more and less than 80 ° C. E: The difference between the minimum fixing temperature and the hot offset occurrence temperature is less than 65 ° C.

  From the above results, it can be seen that the developer corresponding to the example is superior in the low-temperature fixability and further has a wide fixing temperature range as compared with the developer corresponding to the comparative example.

1Y, 1M, 1C, 1K, 107 photoconductor (image carrier)
2Y, 2M, 2C, 2K, charging roller 3Y, 3M, 3C, 3K laser beam 3 exposure device 4Y, 4M, 4C, 4K, 111 developing device (developing means)
5Y, 5M, 5C, 5K Primary transfer rollers 6Y, 6M, 6C, 6K, 113 Photoconductor cleaning device (cleaning means)
8Y, 8M, 8C, 8K Toner cartridges 10Y, 10M, 10C, 10K Unit 20 Intermediate transfer belt 22 Drive roller 24 Support roller 26 Secondary transfer roller (transfer means)
28,115 Fixing device (fixing means)
30 Intermediate transfer member cleaning device 32 Transport roll (discharge roll)
108 Charging device 112 Transfer device 116 Mounting rail 117 Opening portion 118 for static elimination exposure Opening portion 200 for exposure Process cartridge,
P, 300 recording paper (recording medium)

Claims (9)

(A) a polycondensate of a polyvalent carboxylic acid component and (B) a polyhydric alcohol component including the polyhydric alcohol represented by the following general formula (1) and (C) a chain aliphatic polyhydric alcohol. Yes,
The total amount of the (B) polyhydric alcohol represented by the general formula (1) and the (C) chain aliphatic polyhydric alcohol is 60 mol% or more and 100 mol% or less in the total alcohol component, and The molar ratio [(B) / (C)] of the (B) polyhydric alcohol represented by the general formula (1) and the (C) chain aliphatic polyhydric alcohol is 0.1 or more and 1.0 or less. A polyester resin for toner.

[In General Formula (1), R ¹ and R ² each independently represent hydrogen or a methyl group. L ¹ represents a chain alkylene group which may have a substituent, or a divalent group obtained by combining the chain alkylene group with an ester group or an ether group, and L ² and L ³ are each independently , A carbonyl group, an ester group, an ether group, a sulfonyl group, a chain alkylene group which may have a substituent, a cyclic alkylene group which may have a substituent, an arylene group which may have a substituent, and It represents a divalent linking group selected from the group consisting of divalent groups obtained by combining them, and L ¹ and L ² or L ¹ and L ³ may form a ring. A ¹ and A ² represent a rosin ester group. ]   The (C) chain aliphatic polyhydric alcohol is at least one selected from the group consisting of 1,3-propanediol, ethylene glycol, 1,2-propanediol, and neopentyl glycol. The polyester resin for toner described.   The (A) polyvalent carboxylic acid component is at least two of a dicarboxylic acid containing an aromatic structure and a dicarboxylic acid containing a chain aliphatic structure having 4 or less carbon atoms. Polyester resin for toner.   A toner for developing an electrostatic charge image, comprising the polyester resin for toner according to any one of claims 1 to 3.   An electrostatic charge image developer comprising the electrostatic charge image developing toner according to claim 4. Containing the electrostatic image developing toner according to claim 4;
A toner cartridge to be attached to and detached from the image forming apparatus. A developing means for accommodating the electrostatic charge image developer according to claim 5 and developing a latent image formed on the surface of the latent image holding member with the electrostatic charge image developer to form a toner image,
A process cartridge attached to and detached from the image forming apparatus. A latent image carrier,
Charging means for charging the surface of the latent image carrier;
An electrostatic latent image forming means for forming an electrostatic latent image on the surface of the latent image holding member;
Developing means for containing the electrostatic charge image developer according to claim 5 and developing the electrostatic latent image with the electrostatic charge image developer to form a toner image;
Transfer means for transferring the toner image to a recording medium;
Fixing means for fixing the toner image on the recording medium;
An image forming apparatus comprising: A charging step for charging the surface of the latent image carrier,
An electrostatic latent image forming step of forming an electrostatic latent image on the surface of the latent image holder;
A developing step of developing the electrostatic latent image with the electrostatic charge image developer according to claim 5 to form a toner image;
A transfer step of transferring the toner image to a recording medium;
A fixing step of fixing the toner image on the recording medium;
An image forming method comprising: