JP4212465B2 - Binder resin and toner for toner - Google Patents

Description

  The present invention relates to a binder resin for an electrophotographic toner and a toner. More specifically, the present invention relates to a toner binder resin and a toner having a polyester resin structure.

  In recent years, the required performance for copiers and printers using electrophotography has become more sophisticated. In general, electrophotography in copying machines and printers forms an electrostatic latent image on a photoconductor, then develops the latent image with toner, and forms a toner image on a fixing sheet such as paper. After the transfer, a method (heat roll fixing method) in which heat pressing is performed with a heat roll is performed. In this heat roll fixing system, there is a demand for a toner having good fixability that can be fixed at a lower temperature in order to improve economy by reducing power consumption and increase the copying speed.

  In the above-mentioned hot roll fixing method, since the surface of the hot roll and the toner are in contact with each other in a molten state, the toner adheres to the hot roll surface and is transferred again to the next adherend sheet, which becomes a so-called offset phenomenon. Occurs. Not causing this offset phenomenon is one of the important requirements for toner performance.

  Furthermore, with the speeding up of copying machines and printers, there is an increasing demand for higher performance of charged parts. That is, higher durability has been required for toner, and long-term printing stability is becoming necessary.

  In styrene-acrylic resins used as typical toner binder resins, the binder (binder) resin has a low molecular weight and attempts to lower the fixing temperature in order to improve the fixability. Attempts are generally made. However, lowering the molecular weight lowers the resin viscosity, but at the same time lowers the strength and cohesion of the resin, resulting in problems such as deterioration of the durability of the toner and offset phenomenon on the fixing roll. In addition, a method in which a high molecular weight resin and a low molecular weight resin are mixed to broaden the molecular weight distribution is used as the binder resin, or the high molecular weight portion of the binder resin is further crosslinked. It was done. However, in this method, the viscosity of the resin increases, and on the contrary, it becomes difficult to satisfy the fixing property.

  Various types of toners using high-density polyester resins instead of styrene-acrylic resins have been proposed as binder resins that require such contradictory performance (for example, JP-A-61-284771). (Patent Document 1), JP-A-62-291668 (Patent Document 2), JP-B-7-101318 (Patent Document 3), JP-B-8-3663 (Patent Document 4), US Pat. , 833,057 (Patent Document 5) and the like). They use a bisphenol A derivative as a raw material for a polyester resin, or use a tin-based catalyst as a catalyst for producing a polyester. On the other hand, in recent years, there are voices fearing that bisphenol A, tin, and the like may affect the environment in various applications, and there is a voice from the market for products that do not contain them. For this reason, it is necessary to study a toner that satisfies the above requirements.

In addition, as another aspect of environmental problems, it has been pointed out that the use of energy with the recent increase in population has expanded and that resources have been depleted. For this reason, resource saving, energy saving, resource recycling, etc. have been demanded from the market. Among these, PET bottles are collected by local governments and are beginning to be used as various clothing and container materials, but further development of new applications is desired.
JP-A 61-284771 JP-A-62-291668 Japanese Examined Patent Publication No. 7-101318 Japanese Patent Publication No. 8-3663 US Pat. No. 4,833,057

  Accordingly, an object of the present invention is to provide a high-performance binder resin for toner and toner having a structure and configuration that are considered to have a low environmental load.

As a result of intensive studies to achieve the above object, the present inventors have reached the invention described below. That is, the present invention
(1) The structural unit of the following (Formula 1) is 1 mol% or less with all the structural units derived from alcohol as 100 mol%,
Tetrahydrofuran insoluble component (AI) 0.1-40% by mass,
Tetrahydrofuran soluble component (A-S) and 99.9 to 60 wt%, consists of,
Tetrahydrofuran-soluble component (A- S) is, (A- S) in the component, polyvalent 100 mol% of the total of the structural units derived from alcohol, structural units derived from trifunctional or more compounds 1 to 20 mol% der is,
The tetrahydrofuran-insoluble component (AI) is a binder resin for toner containing a polyester resin (A) characterized in that it contains a structural unit derived from a polyvalent isocyanate compound ,

(2) Preferably, it is a binder resin for toner, wherein the acid value of the polyester resin (A) is 30 KOHmg / g or more,
( 3 ) Preferably, the tetrahydrofuran-soluble component (A- S ) is 10 mol% of the structural unit derived from isophthalic acid, with the total number of structural units derived from polyhydric alcohol in the component (A- S ) being 100 mol%. It is a binder resin for toner characterized by containing the above,
( 4 ) Preferably, the structural unit derived from the trifunctional or higher functional compound is a structural unit derived from trimethylolpropane, and is a binder resin for toner,
( 5 ) Preferably, the polyester resin (a) having an OH value of 20 to 90 KOHmg / g and 10 to 60% by mass;
Polyester resin (b) 40- having an OH value of 10 KOH mg / g or less and having a structural unit derived from a trifunctional or higher functional compound of 1 to 20 mol% with respect to 100 mol% of the total amount of alcohol-derived units constituting the polyester. 90% by mass,
It is a binder resin for toner characterized by being obtained from a polyvalent isocyanate,
( 6 ) Preferably, the polyester resin (a) and the polyester resin (b) are
Polyethylene terephthalate,
A polyvalent carboxylic acid;
Polyhydric alcohol,
A binder resin for toner, which is obtained by reacting in the presence of a catalyst selected from a titanium catalyst, a germanium catalyst, and an aluminum catalyst,
( 7 ) A toner containing the above binder resin for toner.

  The binder resin for toner and the toner of the present invention have a structure satisfying the market demand as described above, and exhibit excellent fixing property, smear property, offset resistance, development durability and blocking resistance. For this reason, the industrial significance of the present invention is great.

Hereinafter, the present invention will be described in detail. In the present invention, polycondensation is sometimes referred to as polymerization.
The binder resin for toner used in the present invention contains a polyester resin (A). Said polyester resin (A) contains the structural unit derived from polyhydric carboxylic acid and the structural unit derived from a polyhydric alcohol. Examples of the structural unit derived from the polyvalent carboxylic acid include structural units such as the following (formula 2).

（Ｒ^１は、炭素、水素、および必要に応じて窒素、酸素、燐、珪素から選ばれる元素からなる基である。）
多価アルコール由来の構造単位とは具体的には、下記のような構造のものが好ましい。

(R ¹ is a group consisting of carbon, hydrogen, and, if necessary, an element selected from nitrogen, oxygen, phosphorus, and silicon.)
Specifically, the structural unit derived from a polyhydric alcohol preferably has the following structure.

  Moreover, as a structural unit derived from a polyhydric alcohol, a structural unit like the following (Formula 3) can be illustrated.

（Ｒ^２は、炭素、水素、および必要に応じて窒素、酸素、燐、珪素から選ばれる元素からなる基である。）

(R ² is a group consisting of carbon, hydrogen, and, if necessary, an element selected from nitrogen, oxygen, phosphorus, and silicon.)

  The polyester resin (A) has a component (AI) insoluble in tetrahydrofuran (THF) of 0.1 to 40% by mass and a component soluble in tetrahydrofuran (AS) of 99.9 to 60% by mass. Become. Preferably, the THF-insoluble component (AI) is 0.5 to 25% by mass, and the THF-soluble component (AS) is 99.5 to 75% by mass. If the THF-insoluble component (AI) is less than 0.1% by mass, the offset resistance may not be sufficient, and if it exceeds 40% by mass, the fixability may be insufficient.

  Further, the THF-soluble component (AS) of the present invention is a structural unit derived from a polyfunctional compound having three or more functional groups, wherein the total number of structural units derived from polyhydric alcohol in the component (AS) is 100 mol%. Is 1 to 20 mol%. As such a structural unit, a structural unit such as the following (Formula 4) which is a structural unit derived from a trifunctional or higher alcohol, or a structural unit derived from a polyfunctional carboxylic acid having a trifunctional or higher functionality (Formula 5). The following structural units can be exemplified.

（Ｒ^３は、炭素、水素、および必要に応じて窒素、酸素、燐、珪素から選ばれる元素からなる基である。）

(R ³ is a group consisting of carbon, hydrogen, and, if necessary, an element selected from nitrogen, oxygen, phosphorus, and silicon.)

（Ｒ^４は、炭素、水素、および必要に応じて窒素、酸素、燐、珪素から選ばれる元素からなる基である。）
上記の多価カルボン酸や多価アルコールとして具体的には後述するポリエステル樹脂（ａ）やポリエステル樹脂（ｂ）の項で例示する化合物を挙げることが出来る。

(R ⁴ is a group consisting of carbon, hydrogen, and, if necessary, an element selected from nitrogen, oxygen, phosphorus, and silicon.)
Specific examples of the polyvalent carboxylic acid and polyhydric alcohol include the compounds exemplified in the section of the polyester resin (a) and the polyester resin (b) described later.

  Furthermore, the polyester resin (A) preferably has an acid value of 30 KOHmg / g or more. More preferably, it is 40 KOHmg / g or more, More preferably, it is 50 KOHmg / g. The upper limit value of the acid value varies depending on the molecular structure and cannot be defined unconditionally, but is preferably 120 KOH mg / g, and more preferably 100 KOH mg / g. By controlling the acid value of the polyester resin (A) within the above range, it will be described in detail later, but a sufficient glass transition temperature can be maintained. For example, even when the molecular weight of the polyester resin (A) is lowered. Good storage performance can be expressed. Further, the polyester resin (A) has a high acid value, and thus has high polarity and is considered to be able to express good fixability to paper.

  Moreover, the THF soluble component (AS) of the present invention has a total of 100 mol% of the structural units derived from polyhydric alcohol in the component (AS), and the structural unit derived from isophthalic acid is 10 mol% or more. It is preferable that Furthermore, it is preferable that the structural unit derived from a trifunctional or higher polyfunctional compound is a structural unit derived from trimethylolpropane.

  The THF-soluble component (A-S) has the above-described structure, that is, has a branched structure, and preferably a non-linear structure, so that the binder resin for toner of the present invention has good fixing performance as a toner. Show. This is presumably because the THF-soluble part is a component having a large influence on the fixability, and has a branched structure, so that the crystallinity is low, it is easy to melt and is advantageous for low-temperature fixability. Further, the binder resin for toner of the present invention exhibits good storage stability when used as a toner. By using the branched polyester structure as described above, for example, when compared with a linear polyester having a similar weight average molecular weight, the number of terminals of the molecular chain can be increased. It is advantageous to obtain a polyester resin. A high acid value polyester resin can maintain a relatively high Tg even as a low molecular weight substance advantageous for low-temperature fixability, and is considered to be able to maintain good toner storage performance. In addition, when the molecular weight is lowered, the resin strength generally tends to be weakened, but it is considered that there is an effect of improving the resin strength because the intermolecular force is increased by increasing the polarity of the above-described structure, that is, the terminal. Thereby, the development durability of the toner can be improved.

  The tetrahydrofuran-insoluble component (AI) preferably includes a structural unit derived from a polyvalent isocyanate compound. Examples of the structural unit derived from the polyvalent isocyanate include the following structural units (formula 6).

（Ｒ^５は、炭素、水素、および必要に応じて窒素、酸素、燐、珪素から選ばれる元素からなる基である。）

(R ⁵ is a group composed of carbon, hydrogen, and, if necessary, an element selected from nitrogen, oxygen, phosphorus, and silicon.)

  Since the structural unit derived from the isocyanate compound has a high intermolecular bonding force, it is preferably used because it has an effect of obtaining good durability.

  The structural unit derived from the polyvalent isocyanate of the THF-insoluble component (AI) is a structural unit derived from all the polyvalent carboxylic acid, polyhydric alcohol, and polyvalent amine used as necessary in the polyester resin (A). When the sum is 100 mol%, it is preferably 0.1 to 10 mol%, more preferably 0.5 mol% or more, and 7 mol% or less. When the structural unit derived from the polyvalent isocyanate compound is less than 0.1 mol%, the offset resistance may be insufficient, and when it exceeds 10 mol%, the fixability may be insufficient.

  In the polyester resin (A) of the present invention, each of the structural units described above is, for example, a structural unit derived from a polycarboxylic acid and a structural unit derived from a polyhydric alcohol. The structure which forms is formed. Moreover, the structural unit derived from the above polyisocyanate forms a structure as shown in (Formula 8) with the structural unit derived from the polyhydric alcohol.

  In the polyester resin (A) of the present invention, the content of the structural unit of the following (formula 1) is preferably 1 mol% or less with 100 mol% of all the structural units derived from the alcohol.

また後述するように、本発明に用いられるポリエステル樹脂（Ａ）は、後述するポリエステル樹脂（ａ）とポリエステル樹脂（ｂ）と多価イソシアネートとから得られることが好ましい。そのため、上記ポリエステル樹脂（ａ）、ポリエステル樹脂（ｂ）も式１で示されるアルコール由来の構造単位は、それぞれの樹脂のアルコール由来の構造単位の全てを１００モル％とした場合、１モル％以下であることが好ましい。

Moreover, it is preferable that the polyester resin (A) used for this invention is obtained from the polyester resin (a), the polyester resin (b), and polyhydric isocyanate which are mentioned later so that it may mention later. Therefore, in the polyester resin (a) and the polyester resin (b), the structural unit derived from the alcohol represented by the formula 1 is 1 mol% or less when all the structural units derived from the alcohol of each resin are 100 mol%. It is preferable that

  Many suitable polyhydric alcohol compounds of the polyester resin used for the binder resin for toner are smaller than those having the structure of Formula 1. For this reason, as a polyester resin, since the density of an ester group becomes high, it exists in the tendency for polarity to become high. For this reason, the polyester resin (A) of the present invention has a high affinity with an adherend such as paper, and a toner excellent in fixing property and smearing property can be obtained.

  The polyester resin of the present invention is usually obtained by a polycondensation reaction between a polyvalent carboxylic acid or acid anhydride thereof and a polyhydric alcohol.

The carboxylic acid is preferably a compound having a structure in which 1 to 5, preferably 1 to 3 hydrogen atoms are substituted with a carboxyl group in a hydrocarbon having 1 to 20 carbon atoms. This hydrocarbon is preferably an aliphatic, alicyclic or aromatic hydrocarbon. In particular,
Malonic acid, succinic acid, glutaric acid, adipic acid, azelaic acid, sebacic acid, azelaic acid and other aliphatic dicarboxylic acids, maleic acid, fumaric acid, citraconic acid, itaconic acid and other unsaturated dicarboxylic acids, cyclohexanedicarboxylic acid, etc. Examples thereof include aromatic dicarboxylic acids such as alicyclic dicarboxylic acid, terephthalic acid and isophthalic acid, and phthalic anhydride which is an anhydride of these dicarboxylic acids. In addition, lower alkyl esters of these dicarboxylic acids can be exemplified. These esters can obtain polyesters by a transesterification reaction with a polyhydric alcohol described later.

  Among these, aromatic dicarboxylic acids are preferable, and terephthalic acid and isophthalic acid are more preferable. In particular, when obtaining a polyester resin (b) described later, it is preferable to use isophthalic acid. Of course, other polyvalent carboxylic acids having a structure derived from isophthalic acid may be used. The above polyvalent carboxylic acids can be used in combination of two or more.

  Monovalent carboxylic acids can also be used for the purpose of adjusting the molecular weight. Preferable monovalent carboxylic acids include aliphatic carboxylic acids such as octanoic acid, decanoic acid, dodecanoic acid, myristic acid, palmitic acid, stearic acid, etc. It may be. In addition, these aliphatic monovalent carboxylic acids have the property of lowering the glass transition point, and therefore can be used for adjusting the glass transition point. On the other hand, aromatic carboxylic acids such as benzoic acid and naphthalenecarboxylic acid may be used. These monovalent carboxylic acids are used in an amount of 0 mol% to 30 mol%, preferably 0 mol% to 15 mol%, based on the structural units derived from all carboxylic acids. Two or more monovalent carboxylic acids can be used in combination.

  A trivalent or higher carboxylic acid can be used as the above trifunctional or higher functional compound. It is also suitable for adjusting the molecular weight. Specific examples of such a compound include trimellitic acid, pyromellitic acid, and acid anhydrides thereof.

  As the polyester resin in the present invention, a carboxylic acid that has been used in producing the conventional polyester resin as described above can be used, but it is preferable not to use a carboxylic acid having a bisphenol A skeleton.

  Specific examples of the polyhydric alcohol of the present invention include ethylene glycol, 1,4-butanediol, 1,2-propylene glycol, 1,3-propylene glycol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, diethylene glycol, triethylene glycol, dipropylene glycol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, 2-ethyl-1,3-hexanediol, cyclohexanedimethanol, Examples thereof include polyhydric alcohols such as hydrogenated bisphenol A, 1,4-cyclohexanedimethanol, hydroquinone, resorcin, and phthalyl alcohol. Of these, preferred are neopentyl glycol having a branched and / or cyclic structure, 2-ethyl-1,3-hexanediol, trimethylolethane, cyclohexanedimethanol, hydrogenated bisphenol A, and 1,4-cyclohexanedimethanol. Neopentyl glycol is preferred. Said polyhydric alcohol can be used in combination of 2 or more type.

  The above polyhydric alcohol is a compound having a bisphenol A skeleton, specifically, bisphenol A, bisphenol A-2 propylene oxide adduct, bisphenol A-3 propylene oxide adduct, bisphenol A-polypropylene oxide adduct, bisphenol A. -2 ethylene oxide adduct, bisphenol A-3 ethylene oxide adduct, and those having a structure different from bisphenol A-polyethylene oxide adduct are preferred, and the compound having the bisphenol A structure as described above is all alcohol. It is preferably used in an amount of 1 mol% or less.

A monohydric alcohol can also be used for the purpose of adjusting the molecular weight.
Preferable monovalent alcohols include aliphatic monoalcohols such as octanol, decanol, dodecanol, myristyl alcohol, palmityl alcohol, stearyl alcohol, and the like, and may have a branched or unsaturated group. These monohydric alcohols are used in an amount of 0 mol% to 30 mol%, preferably 0 mol% to 15 mol%, based on the structural units derived from all alcohols.

  A trihydric or higher polyhydric alcohol is suitably used as a trifunctional or higher functional compound. Moreover, it is a compound suitable also for the effect of extending the molecular weight distribution mentioned later, and for forming a THF insoluble component. Specific examples include trimethylolpropane, glycerin, 2-methylpropanetriol, trimethylolethane, pentaerythritol, sorbit, sorbitan, and the like, and trimethylolpropane, glycerin, 2-methylpropanetriol, and trimethylolethane are more preferable. . In particular, trimethylolpropane is preferably used. Two or more monohydric alcohols and trihydric or higher polyhydric alcohols can be used in combination.

  The polyester resin in the present invention is usually obtained by polycondensation of the above polycarboxylic acid and polyhydric alcohol, but it is preferable to use polyethylene terephthalate (PET) for the polycondensation reaction. The PET may be recycled PET collected from waste. Recycled PET is processed into flakes and has a weight average molecular weight of about 30000 to 90000, but is limited to the molecular weight distribution, composition, manufacturing method, form of use, etc. of PET. Absent. Moreover, it is not restricted to a recycled product.

  The content of the PET is 40 mol% or more as the number of moles of structural units derived from ethylene glycol, which is an alcohol component derived from PET, when the number of moles of all alcohol components in the polyester resin (A) is 100 mol%. Is preferable in view of the polycondensation reactivity described later.

  The alcohol component preferably contains at least PET-derived ethylene glycol and an alcohol having a branched structure and / or a cyclic structure, particularly preferably neopentyl glycol.

  The polycondensation reaction for obtaining the polyester resin in the present invention can be performed by a known method such as high-temperature polycondensation without solvent and solution polycondensation in an inert gas such as nitrogen gas. The ratio of the polyvalent carboxylic acid and polyhydric alcohol used in the reaction is generally 0.7 to 1.4 in terms of the ratio of the latter hydroxyl group to the former carboxyl group.

  When PET is used as a raw material, PET and an alcohol monomer may be added in advance, and after the depolymerization reaction of PET, the remaining alcohol and acid monomer may be added to perform a polycondensation reaction. Alternatively, PET, alcohol monomer, and acid monomer may be charged together and the depolymerization reaction and polycondensation reaction may be performed simultaneously.

  In the polycondensation reaction and the depolymerization reaction when obtaining the polyester resin, the catalyst used is a catalyst containing an element selected from titanium, germanium, and aluminum, such as a tin-based catalyst such as dibutyltin oxide and antimony trioxide. It is preferably different from the antimony catalyst or the like. It is more preferable to use titanium alkoxide, titanium acylate, titanium chelate or the like as the titanium-containing catalyst, and particularly preferably tetranormal butyl titanate, tetra (2-ethylhexyl) titanate, tetramethyl titanate, tetraisopropyl titanate. It is preferable to use it. Examples of the germanium-containing catalyst include germanium dioxide. Moreover, it is preferable that it is 0.01 mass%-1.00 mass% as addition amount in that case. A plurality of the above catalysts may be used simultaneously, and the catalyst may be added at the start of polymerization or during the polymerization. In the present invention, the depolymerization reaction refers to various polycondensation reverse reactions such as a hydrolysis reaction and a transesterification reaction.

  Specific examples of titanium alkoxides that correspond to the above-mentioned catalyst containing titanium include: ORGATIX TA-25 (tetranormal butyl titanate), TA-30 (tetra (2-ethylhexyl) titanate), TA-70 ( Tetramethyl titanate), etc., as titanium acylates, such as orgatics TPHS (polyhydroxytitanium stearate), etc., and as titanium chelates, organics TC-401 (titanium tetraacetylacetonate), TC-200 (titanium octylene glyco) Rate), TC-750 (titanium ethyl acetoacetate), TC-310 (titanium lactate), TC-400 (titanium triethanolamate), etc. (all manufactured by Matsumoto Pharmaceutical Co., Ltd.) Limited to this Not.

  A catalyst containing titanium is generally known as a catalyst for transesterification because its catalytic activity is deactivated when water is present in the system. In order to suppress the reaction with water generated during the polycondensation reaction and the deactivation of the catalytic activity, it is preferable to use PET as a raw material as described above.

  The polyester resin in the present invention is preferably produced by depolymerization and polycondensation at 200 ° C. to 270 ° C., preferably produced by polycondensation, and more preferably produced at 220 ° C. to 260 ° C. When the reaction temperature is 200 ° C. or lower, the solubility of PET during depolymerization may be low, or the solubility of polyvalent carboxylic acid components such as terephthalic acid in a polyhydric alcohol may be reduced, resulting in a decrease in reaction rate. is there. When the reaction temperature is 270 ° C. or higher, decomposition of the raw material may occur.

  The binder resin for toner of the present invention using the polyester resin obtained as described above has a content of an element selected from titanium, germanium and aluminum of 10 to 1500 ppm, preferably 30 to 1000 ppm. Moreover, it is preferable that content of tin is 0-1 ppm, More preferably, it is 0 ppm.

  When the above-mentioned recycled PET is used for the above polycondensation reaction, it may contain a residue of the antimony catalyst used during the production of the PET. In this case, the content of antimony is 100 ppm or less, and further 50 ppm or less. Is preferable.

  The metal analysis in the resin can be confirmed by using a known metal analysis method such as an atomic absorption analysis method or a plasma emission analysis method.

  The polyester resin (a) of the present invention will be described in detail. The polyester resin (a) of the present invention has a structure derived from the above-described trihydric or higher polyhydric alcohol such as trimethylolpropane at a ratio of 1 to 20 mol% when the number of moles of all alcohol components is 100 mol%. It is preferable to have it, More preferably, it is 2-12 mol%. If the amount of the trihydric or higher polyhydric alcohol is less than 1 mol%, it may be difficult to polymerize in the urethanization reaction described later, and offset resistance may be insufficient. In some cases, the fixing amount may be insufficient. On the other hand, if it exceeds 20 mol%, the viscosity during polymerization is remarkably increased and the polyester resin (a) may not be obtained stably.

  The polyester resin (a) has a structure derived from terephthalic acid of 60 mol% or more, a structure derived from ethylene glycol of 40 mol% or more, and a structure derived from neopentyl glycol when the number of moles of all alcohol components is 100 mol%. It is preferable to have a structure of 20 mol% or more. By controlling to the said composition, the polyester resin (a) which has a favorable thermophysical property can be obtained.

  Furthermore, the molecular weight of the polyester resin (a) is preferably 1000 to 6000, more preferably 1000 to 4000 in terms of number average molecular weight (Mn). When the number average molecular weight is less than 1000, Tg may be too low to easily cause blocking, and when it exceeds 4000, the fixability may be insufficient.

  The OH value of the polyester resin (a) is 20 to 90 KOHmg / g. Preferably, it is 30 KOHmg / g or more and 80 KOHmg / g or less. In the present invention, it is considered that the polyester resin (a) mainly reacts with the later-described polyvalent isocyanate to increase the molecular weight. When the OH value is less than 20 KOH mg / g, the reaction amount with the polyvalent isocyanate decreases, that is, the urethane content decreases, and the development resistance of the toner may be insufficient. In addition, sufficient high molecular weight may not be achieved. When the OH value is greater than 90 KOH mg / g, the molecular weight of the polyester resin (a) tends to be low, so that it is difficult to increase the molecular weight, and offset resistance may be insufficient.

  Moreover, it is preferable that the glass transition point of a polyester resin (a) is 0-50 degreeC, More preferably, it is 25-50 degreeC. When the glass transition point is less than 0 ° C, the blocking resistance may be insufficient, and when it exceeds 50 ° C, the fixability may be insufficient.

  Next, the polyester resin (b) of the present invention will be described in detail. The polyester resin (b) of the present invention preferably contains 1 to 20 alcohols and / or carboxylic acids having a trifunctional or higher polyfunctional group as a trifunctional or higher functional compound when the number of moles of all alcohol components is 100 mol%. It has mol%. More preferably, it is 2 to 15 mol%. As the trifunctional or higher functional compound, alcohol is more preferable, and more specifically, trimethylolpropane is preferable. It is considered that good fixing performance can be exhibited by forming a branched polyester structure using the polyfunctional compound. On the other hand, when the branched polyester structure is used, the number of molecular chain terminals can be increased when compared with, for example, a linear polyester having a comparable weight average molecular weight. As a result, a high acid value polyester resin can be obtained as described above, and a relatively high Tg can be maintained even when the molecular weight is lowered. For this reason, it is considered that the polyester resin obtained by the urethanization reaction described later can exhibit good storage performance when used as a toner. When the structural unit derived from a trifunctional or higher compound is 1 mol% or less, the effect of branching of the polyester is reduced, so that a sufficient effect may not be expressed, and when it is 20 mol% or more, In some cases, the viscosity of the polyester resin increases, making it difficult to develop good fixability.

  Moreover, it is preferable that the polyester resin (b) has 10 mol% or more of structural units derived from isophthalic acid. By introducing a structural unit derived from isophthalic acid, the molecular structure of the polyester resin can be made non-linear, and as with the introduction of a structural unit derived from a tri- or higher functional compound, good fixing performance as a toner is achieved. It can be expressed.

  The polyester resin (b) has a structure derived from terephthalic acid of 60 mol% or more, a structure derived from ethylene glycol of 40 mol% or more, and a structure derived from neopentyl glycol of 20 mol% or more. Is preferred. By adopting such a structure, it is possible to avoid crystallization of the polyester resin (b), whereby a toner binder resin having a good fixability described later can be obtained. Further, by having such a structure, good pulverization property can be exhibited at the time of toner formation.

  The molecular weight of the polyester resin (b) is preferably 1000 to 4500 in terms of number average molecular weight, more preferably 1000 to 4000, and still more preferably 1000 to 3000. If the number average molecular weight is less than 1000, Tg may be too low to easily cause blocking, and if it exceeds 4500, the fixability may be insufficient.

  The OH value of the polyester resin (b) is 10 KOH mg / g or less. In the present invention, by controlling the OH value of the polyester resin (b) within the above range, the polyester resin (b) rarely reacts with the polyvalent isocyanate described later, and even after becoming a urethane-modified polyester resin Regarding the part derived from the resin (b), it is considered that there is no significant change in the molecular weight. Therefore, since the polyester resin (b) mainly forms the THF-soluble component (AS), the molecular design of the THF-soluble component (AS) can be almost determined by the polyester resin (b). I can do it.

  When the OH value of the polyester resin (b) exceeds 10 KOH mg / g, it may react with a polyisocyanate described later, the molecular weight will increase more than necessary, and the fixability may be insufficient.

  Moreover, it is preferable that the acid value of a polyester resin (b) is 30 KOHmg / g or more, More preferably, it is 40 KOHmg / g or more, More preferably, it is 50 KOHmg / g. The upper limit value of the acid value varies depending on the molecular structure and cannot be defined unconditionally, but is preferably 120 KOH mg / g, and more preferably 100 KOH mg / g. When the acid value of the polyester resin (b) is within the above range, a sufficient glass transition temperature can be maintained. For example, even when the molecular weight of the polyester resin (b) is lowered, good storage performance is expressed. Can do. Further, it is considered that excellent fixability to paper can be expressed by making the terminal of the molecular chain highly polar. Also, when the molecular weight is lowered, the resin strength generally tends to be weakened, but the resin strength is improved by maintaining the above high acid value, that is, by making the terminal highly polar. It is thought that there is also an effect. Thereby, the development durability of the toner can be improved. In order to obtain such a high acid value polyester resin, it is preferable to produce a polyester using components such as the above-described trifunctional or higher functional compounds within the above-described range.

  It is preferable that the glass transition point of a polyester resin (b) is 40-80 degreeC, More preferably, it is 50-70 degreeC. If the glass transition point is less than 40 ° C, the blocking resistance may be insufficient, and if it exceeds 80 ° C, the fixability may be insufficient.

  In addition, the acid value in this invention points out mg number of potassium hydroxide required in order to neutralize 1 g of resin. The OH value refers to the number of mg of potassium hydroxide necessary to neutralize the acid anhydride necessary to esterify the OH group in 1 g of resin. The OH number is measured by back titration with a known acid anhydride, and in particular, a method using phthalic anhydride as the acid anhydride and imidazole as the catalyst is desirable. For these acid anhydrides and solvents that dissolve the catalyst, Use pyridine as the reaction reagent. As a solvent for diluting these after reacting the reaction reagent with the resin, a solvent having excellent resin solubility such as pyridine or tetrahydrofuran is used.

  Further, the content ratio of the polyester resin (a) and the polyester resin (b) of the present invention is a mass ratio, and (a) :( b) is preferably 10:90 to 60:40, particularly 10:90 to 50:50. Is more preferable. When the content of the polyester resin (a) is less than 10% by mass, the offset resistance may be insufficient, and when the content of the polyester resin (a) exceeds 60% by mass, the fixability may be insufficient. There is.

  Examples of the polyvalent isocyanate of the present invention include diisocyanates such as hexamethylene diisocyanate, isophorone diisocyanate, tolylene diisocyanate, xylylene diisocyanate, tetramethylene diisocyanate, and norbornene diisocyanate. In addition, trivalent or higher polyvalent isocyanates can also be used. The amount of polyisocyanate used is 0.6 to 1.6 molar equivalents as NCO groups per equivalent of total OH groups of the polyester resin (a) and the polyester resin (b). Is preferable, and an amount of 0.8 to 1.4 molar equivalent is particularly preferable. The high molecular weight compound obtained by the reaction with the isocyanate compound mainly forms a tetrahydrofuran-insoluble component (AI).

  When the amount of polyisocyanate used is less than 0.6 molar equivalent as an NCO group, offset resistance may be insufficient, and when it exceeds 1.6 molar equivalent, the OH group to be reacted Insufficient NCO groups remain, making it difficult to polymerize, and offset resistance may be insufficient.

  The so-called urethane elongation reaction in which the polyvalent isocyanate is reacted with the OH group in the polyester to increase the molecular weight can be obtained by a solvent method, a bulk method, a method using an extruder, or the like. More specifically, for example, it can be produced by the following method. That is, a mixture of the polyester resin (a) and the polyester resin (b) is fed to a twin-screw extrusion kneader at a constant speed, and at the same time, polyisocyanate is also injected at a constant speed and reacted at 100 to 200 ° C. while being dispersed and mixed. Let In the present invention, it is considered that the polyester resin (a) mainly reacts with the polyvalent isocyanate. However, as shown in the above method, the urethane elongation reaction of the polyester resin (a) is performed in the presence of the polyester resin (b). Is the most preferable method for the urethane elongation reaction of the present invention. The urethane-modified polyester obtained by the above method comprises a polyester resin (b) component that is considered to contribute mainly to fixing properties, and a reaction product of the polyester resin (a) that is considered to contribute mainly to offset resistance and a polyvalent isocyanate. It is considered that better fixing performance and anti-offset performance can be exhibited by entanglement at the molecular level.

  Of course, the polyester resin (a) and the polyvalent isocyanate may be contacted and kneaded and then kneaded with the polyester resin (b).

  The melting temperature of the toner binder resin of the present invention obtained as described above is preferably 110 ° C. or higher and 180 ° C. or lower. By having a melting temperature within this range, it is advantageous to satisfy both the fixing performance and the offset performance.

  The binder resin for toner of the present invention may contain a polyolefin wax such as polyethylene wax and polypropylene wax for the purpose of enhancing the performance of preventing the offset phenomenon to the roller, that is, the offset resistance, and the addition amount thereof is In the toner binder resin, the content is preferably in the range of 0 to 10% by mass.

  Specific product names of those corresponding to the polyolefin wax include Mitsui Chemicals high wax 800P, 400P, 200P, 100P, 720P, 420P, 320P, 405MP, 320MP, 4051E, 2203A, 1140H, NL800, NP055, NP105, NP505, NP805, etc. can be illustrated, but it is not limited to this.

  Furthermore, the binder resin for toner of the present invention may contain natural waxes such as ceramic wax, rice wax, sugar wax, urushi wax, beeswax, carnauba wax, candelilla wax, montan wax, and the addition amount thereof is: It is preferably in the range of 0 to 10% by mass in the binder resin for toner.

  Further, in the binder resin for toner of the present invention, a resin such as a styrene copolymer, a polyol resin, a polyurethane resin, a polyamide resin, a silicone resin, etc. is added in addition to the polyester resin as long as the effects of the present invention are not impaired. It may be added. The addition amount is preferably 0 to 50% by mass in the binder resin for toner.

Hereinafter, the toner of the present invention will be described in detail.
The toner of the present invention contains at least the binder resin for toner of the present invention, a charge adjusting agent (CCA), a colorant, and a surface treatment agent. The toner of the present invention is a toner for a so-called two-component developer that is developed by mixing with a carrier, a so-called magnetic one-component toner containing magnetic powder in the toner, or a one-component toner that is developed only with the toner. It can be used as a toner. In this case, the amount of the binder resin for toner of the present invention is preferably 50 to 95% by mass in the toner.

  As the colorant, conventionally known carbon black, magnetite, organic pigments and the like can be used. The addition amount is preferably 3 to 15 parts by mass with respect to 100 parts by mass of the binder resin for toner.

  As the charge control agent, known charge control agents such as nigrosine, quaternary ammonium salts and metal-containing azo dyes can be appropriately selected and used, and the amount used is 100 parts by weight of toner binder resin. In the present invention, it is preferably 0.1 to 10 parts by mass that are usually used.

  As the surface treatment agent, known ones such as silica and acid value titanium can be used, and the addition amount is preferably 0.1 to 20 parts by mass with respect to 100 parts by mass of the binder resin for toner. It is.

  The toner of the present invention may contain a polyolefin wax, and the amount thereof is preferably 0 to 10 parts by mass with respect to 100 parts by mass of the binder resin for toner. Specific examples include the aforementioned polyolefin waxes.

  Examples of the method for producing the toner of the present invention containing these materials include the following methods. The toner binder resin of the present invention, a colorant, and if necessary, other additives are thoroughly mixed with a powder mixer, and then melted and kneaded using a kneader such as a heating roll, a kneader, and an extruder. Mix the components thoroughly. After cooling this, pulverization and classification are performed to collect particles usually in the range of 8 to 20 μm, and a surface treatment agent is applied by a powder mixing method to obtain a toner.

  The toner obtained by the present invention can be used in various development processes such as a cascade development method, a magnetic brush method, and a touch-down development method, but is not limited thereto.

Further, the toner obtained by the present invention can be used in various fixing methods other than the oilless fixing method. Specifically, it can be used for an oil application heat roll method, a flash method, an oven method, a pressure fixing method, and the like. Furthermore, the toner of the present invention can be used in various cleaning methods such as a fur brush method and a blade method.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited by these Examples.

The measurement of the molecular weight and molecular weight distribution of the binder resin for toner in the present invention is obtained using GPC. The measurement was performed under the following conditions using a commercially available monodisperse standard polystyrene as a standard.
Detector: SHODEX RI-71S type refractive index measuring device (Showa Denko)
Solvent; Tetrahydrofuran Column; 1 KF-G, 3 KF-807L, 1 KF800D connected in series
(All columns are made by Showa Denko)
Flow rate: 1.0 ml / min Sample: 0.25% THF solution Note that the reliability of the measurement is the Mw / Mn of the NBS706 polystyrene sample (Mw = 288,000, Mn = 137,000, Mw / Mn = 2.11) performed under the above measurement conditions, It can be confirmed by 2.11 ± 0.10.

  Further, the glass transition point (Tg) in the present invention was measured by DSC-20 (manufactured by Seiko Denshi Kogyo Co., Ltd.) according to the differential scanning calorimetry (DSC). About 10 mg of a sample was heated to about 200 ° C. in advance, held for 5 minutes, and then immediately cooled to room temperature (25 ° C.) to unify the thermal history of the resin, and then from −20 ° C. to 100 ° C. The temperature was raised at 10 ° C./min until Tg was determined from the intersection of the obtained curve base line and the endothermic peak slope.

In the present invention, the THF-insoluble component amount and the THF-soluble component amount are determined as follows. About 5% by weight solution is prepared using about 2.5 g of resin and about 47.5 g of THF. (Hereinafter, the concentration of the above solution is referred to as “RC”.) That is, the above mixture is stirred at 25 ± 3 ° C. for 12 hours to completely dissolve the soluble components. The resulting solution is then allowed to stand for 16 hours. After the insoluble part and the supernatant are separated, the supernatant is analyzed for concentration analysis. (Hereinafter, the concentration of the supernatant is referred to as “SC”.) This value is calculated from a measured value of the mass of the remaining resin after collecting 5 g of the supernatant and drying at 150 ° C. for 1 hour to remove tetrahydrofuran. )
The values of the THF-insoluble component and the THF-soluble component are obtained from the RC value and the SC value according to the following formula.
THF soluble component ratio = (SC / RC) x 100 (%)
THF insoluble component ratio = [(RC-SC) / RC] × 100 (%)
Next, the supernatant is removed from the solution by decantation, and the residue is washed several times with THF. The residue is dried at 40 ° C. under reduced pressure to obtain a THF-insoluble component.

  The acid value in the present invention refers to the number of mg of potassium hydroxide necessary to neutralize 1 g of the resin. The acid value was measured by a neutralization titration method. 5 g of a sample was dissolved in 50 cc of a mixed solvent of xylene / dimethylformamide = 1/1 (mass ratio), a few drops of phenolphthalein / ethanol solution was added as an indicator, and titration was performed with 1/10 normal KOH aqueous solution. The point at which the color of the sample solution colored from colorless to purple was used as the end point, and the acid value (KOHmg / g) was calculated from the titration amount and the sample mass at this time.

  Moreover, the OH value in the present invention was measured by back titration with the following acid anhydride. That is, 5 cc of a separately prepared phthalating reagent (prepared at a ratio of 500 cc of pyridine / 70 g of phthalic acid / 10 g of imidazole) was added to 2 g of resin and dissolved, and then allowed to stand at 100 ° C. for 1 hour. Thereafter, 1 cc of water, 70 cc of tetrahydrofuran and several drops of phenolphthalein / ethanol solution were added to the resin solution, and titration was performed with a 0.4 N NaOH aqueous solution. The point where the color of the sample solution was changed from colorless to purple was used as the end point, and the OH value (KOHmg / g) was calculated from the titration amount and the sample mass.

Next, a toner evaluation method performed in the present invention will be described below.
1. Fixing property A heat roller fixing device modified so that the temperature and fixing speed of a fixing unit of a commercially available copying machine can be controlled arbitrarily after an unfixed image is created by a copying machine modified from a commercially available electrophotographic copying machine. Was used to fix the unfixed image. The fixing speed of the heat roll was 250 mm / sec, and the toner was fixed by changing the temperature of the heat roller by 5 ° C. The obtained fixed image was subjected to a load of 0.3 kgf with a cotton cloth and rubbed 10 times, and the image density before and after the friction test was measured with a Macbeth reflection densitometer. The lowest fixing temperature at which the change rate of image density at each temperature was 80% or more was defined as the minimum fixing temperature, and evaluation was performed according to the following rules. The heat roller fixing device used here does not have a silicone oil supply mechanism. That is, no offset prevention liquid is used. The environmental conditions were normal temperature and normal pressure (temperature 22 ° C., relative humidity 55%).
1; Minimum fixing temperature ≤ 160 ° C
2; 180 ° C ≥ minimum fixing temperature> 160 ° C
3; Minimum fixing temperature> 180 ° C

2. Smearing property According to the evaluation of fixing property, an unfixed image was prepared, and this unfixed image was fixed by a heat roller fixing device. The toner was fixed at a fixing speed of a hot roll of 250 mm / sec and a temperature of a hot roller of 170 ° C. The solid black portion (ID = 1.35 to 1.45; measured with a Macbeth densitometer) of the obtained fixed image was rubbed 5 times with a commercial copy paper under a load of 500 gf. The degree of stain on the copy paper after the rubbing test was confirmed by measuring the image density (ID) of the copy paper with a Macbeth reflection densitometer, and evaluated according to the following rules. The environmental conditions were normal temperature and normal pressure (temperature 22 ° C., relative humidity 55%).
1 ； ID ≦ 0.8 (less dirty)
2; 0.12 ≥ ID> 0.8
3; ID> 0.12 (a lot of dirt)

3. Offset resistance The evaluation of the offset resistance is based on the measurement of the minimum fixing temperature, but after the unfixed image is created by the copying machine, the toner image is transferred and the fixing process is performed by the above-mentioned hot roller fixing device. Then, the operation of visually observing whether or not toner contamination occurs on the transfer paper by sending the white transfer paper to the heat roller fixing device under the same conditions as the temperature setting temperature of the heat roller fixing device. Were successively raised, and the lowest set temperature at which the toner was smeared was defined as the offset generation temperature, which was evaluated according to the following rules. The fixing speed of the hot roll was 250 mm / sec. The environmental conditions were normal temperature and normal pressure (temperature 22 ° C., relative humidity 55%).
1 ； Offset generation temperature ≧ 230 ℃
2 ； 230 ℃> Offset generation temperature

4. Development durability After performing a continuous shooting test for 70,000 sheets with a commercially available copying machine (manufactured by Toshiba, Plesio 5560), the deterioration of image density and image quality was confirmed and evaluated according to the following rules.
1: Deterioration was not confirmed
2: Deterioration was confirmed

5. Blocking resistance After being left for 48 hours under an environmental condition of 55 ° C and 55% relative humidity, 5g of toner is placed on a 150 mesh screen, and the scale of the resistance tester of the powder tester (Hosokawa Institute of Powder Technology) Set to 3 and apply vibration for 5 minutes. The weight remaining on the mesh after vibration was measured, the remaining weight ratio was determined, and evaluated according to the following rules.
1: Less than 30%
2: Greater than 30%

Polyester resin production example Polyester resins (a) and (b) were produced by the following method. The resin a-1 is specifically exemplified. Resins b-1 to b-5 were obtained in the same manner as the resin a-1, except that the monomer composition was changed to the blending ratio shown in Table 1. In addition, the acid value, OH value, Tg, and Mn of the obtained resin are shown together in Table 1.
A 5-liter four-necked flask was equipped with a reflux condenser, a water separator, a nitrogen gas inlet tube, a thermometer, and a stirrer, and flake-like recycled PET (weight average) with respect to 100 mol% of all alcohol components. (Molecular weight: 75000) in units of ethylene glycol unit in PET, 50 mol%, neopentyl glycol 35 mol%, triethylene glycol 8 mol%, trimethylolpropane 7 mol%, terephthalic acid 38 mol%, and tetra (2-ethylhexyl) titanate (Matsumoto Pharmaceutical Co., Ltd.) 0.4% by mass (Orgatics TA-30) manufactured by Co., Ltd. was charged, and depolymerization and dehydration polycondensation were performed at 240 ° C. while introducing nitrogen into the flask. When the acid value of the reaction product reached the value shown in Table 1, it was extracted from the flask, cooled, and pulverized to obtain resin a-1.

以下に実施態様について実施例１を代表例として具体的に記述する。樹脂２〜７について、即ち実施例２〜４及び比較例１〜３についても実施例１と同様な操作を行って樹脂およびトナーを得て評価を行った。これらについて、樹脂ａと樹脂ｂの配合比やトリレンジイソシアネート添加量、樹脂分析結果（ＴＨＦ不溶成分、酸価、ＴＨＦ可溶成分中のトリメチロールプロパン量）、トナー性能評価結果を実施例１と併せて表２に示す。

In the following, the embodiment will be specifically described using Example 1 as a representative example. For the resins 2 to 7, that is, for Examples 2 to 4 and Comparative Examples 1 to 3, the same operations as in Example 1 were performed to obtain resins and toners, and evaluation was performed. For these, the blending ratio of resin a and resin b, the amount of tolylene diisocyanate added, the result of resin analysis (THF insoluble component, acid value, amount of trimethylolpropane in THF soluble component), and toner performance evaluation results are shown in Example 1. The results are also shown in Table 2.

Example 1
Resin a-1 (28% by mass), resin b-1 (72% by mass) and tolylene diisocyanate (2.1% by mass) at a rate of 15 kg / h as a total flow rate of the resin, a twin-screw extrusion kneader (Kurimoto Tekko) The resin 1 was obtained by feeding to KEX-40) and performing a kneading reaction at a temperature of 170 ° C. and a screw rotation speed of 150 rpm.

  Carbon black (MA-100, manufactured by Mitsubishi Chemical Co., Ltd.) 6 mass%, charge control agent (BONTRON E-84; manufactured by Orient Chemical Industry Co., Ltd.) 1.0 mass%, carnauba wax (100% by mass) Carnauba No. 1; imported by Yoko Kato Co., Ltd.) 2.0% by mass was dispersed and mixed with a Henschel mixer, and then melted at 120 ° C and 150rpm with a twin-screw extrusion kneader PCM-30 (Ikegai Iron Works) By kneading, a bulky toner composition was obtained. This toner composition was coarsely pulverized with a hammer mill. Further, the mixture was finely pulverized by a jet pulverizer (IDS2 type, manufactured by Nippon Pneumatic Co., Ltd.), and then classified by air flow to obtain a fine toner powder having an average particle size of 9.0 μm. Next, hydrophobic silica (R-972, manufactured by Aerosil Co.) is added from the outside at a ratio of 0.3% by mass with respect to 100% by mass of the above toner fine powder, and this is mixed with a Henschel mixer. Toner was obtained. Using the toner particles, fixing property, offset resistance, and development durability were examined.

表２の結果から明らかなように、本発明により製造されたトナー用樹脂１〜４を用いたトナーは、いずれも優れたトナー性能を示した。

As is apparent from the results in Table 2, all the toners using the toner resins 1 to 4 produced according to the present invention exhibited excellent toner performance.

Claims (7)

All the structural units derived from alcohol are 100 mol%, and the structural unit of the following (formula 1) is 1 mol% or less,
Tetrahydrofuran insoluble component (AI) 0.1-40% by mass;
Tetrahydrofuran soluble component (A-S) and 99.9 to 60 wt%, consists of,
Tetrahydrofuran-soluble component (A- S) is, (A- S) in the component, polyvalent 100 mol% of the total of the structural units derived from alcohol, structural units derived from trifunctional or more compounds 1 to 20 mol% der is,
A binder resin for toner comprising a polyester resin (A), wherein the tetrahydrofuran-insoluble component (AI) contains a structural unit derived from a polyvalent isocyanate compound .

The binder resin for toner according to claim 1, wherein the acid value of the polyester resin (A) is 30 KOH mg / g or more. The tetrahydrofuran-soluble component (A- S ) contains 10 mol% or more of structural units derived from isophthalic acid , with the total number of structural units derived from polyhydric alcohol in the component (A- S ) being 100 mol%. The toner binder resin according to claim 1. 2. The binder resin for toner according to claim 1, wherein the structural unit derived from a trifunctional or higher functional compound is a structural unit derived from trimethylolpropane. 10 to 60% by mass of a polyester resin (a) having an OH value of 20 to 90 KOHmg / g,
Polyester resin (b) 40- having an OH value of 10 KOH mg / g or less and having a structural unit derived from a trifunctional or higher functional compound of 1 to 20 mol% with respect to 100 mol% of the total amount of alcohol-derived units constituting the polyester. 90% by mass,
The binder resin for toner according to claim 1, wherein the binder resin is obtained from a polyvalent isocyanate. The polyester resin (a) and the polyester resin (b)
Polyethylene terephthalate,
A polyvalent carboxylic acid;
Polyhydric alcohol,
6. The toner binder resin according to claim 5 , wherein the binder resin is obtained by reacting in the presence of a catalyst selected from a titanium catalyst, a germanium catalyst, and an aluminum catalyst. A toner comprising the toner binder resin according to claim 1.