JP2020158603A - Polyester resin and manufacturing method thereof - Google Patents

Abstract

To provide polyester resin which is available for toner or adhesive, is superior to productivity, is superior to dispersibility of additives responding to each application, can fix in wide temperature zone from low temperature to high temperature, and can contribute to environmental load reduction.SOLUTION: As for polyester resin having unsaturated double bond, THF insoluble matter (1) of the polyester resin is not more than 5 mass%, radical initiating reagent is less than 0.15 mass%, and THF insoluble matter (2) after crosslinking with polyester resin which softening temperature is 100°C is not less than 10 mass%.SELECTED DRAWING: None

Description

The present invention relates to a polyester resin and a method for producing the same.

In response to recent demands for higher speed, smaller size, and energy saving of printers, the temperature of the fixing part of the heat roller type has been lowered. Therefore, there is a demand for a binder resin for toner having a wide fixing width that can be fixed at a lower temperature, and has a toner storage stability (storage stability) and an offset on the high temperature resistant side. In addition, there is a demand for materials that generate less volatile components due to heat during fixing and raw materials that do not contain heavy metal materials that have a large environmental impact.
For example, in Patent Document 1, a saturated polyester resin using a titanium-based catalyst having a low environmental load is used as a molding material.
Further, Patent Document 2 describes a method for producing a binder resin for toner, in which two types of unsaturated polyester resins having different molecular weights and softening temperatures are melt-kneaded in the presence of a radical reaction initiator.
Further, Patent Document 3 describes a method for producing a high molecular weight unsaturated polyester resin for a molding material application in which an unsaturated monomer is mixed with a high molecular weight unsaturated polyester resin and then radically polymerized with an initiator to form the resin. There is.

WO2006 / 079963 Japanese Unexamined Patent Publication No. 2013-144738 Japanese Unexamined Patent Publication No. 4-183713

However, the material described in Patent Document 1 does not use unsaturated polyester, and its performance as a toner that can be widely fixed at low to high temperatures and as an adhesive is insufficient.
Further, in the material of Patent Document 2, an initiator is added to unsaturated polyester and reacted, and it can be applied to a wide range of fixable toner from low temperature to high temperature. However, since the amount of the initiator added is large, the initiator There is a large amount of derived residue, which increases the environmental load.
Further, in the material of Patent Document 3, since the unsaturated polyester and the unsaturated monomer are reacted, the amount of the initiator added is large, the residue derived from the initiator tends to increase, and the environmental load increases.
The present invention is a polyester that can be used for toners, adhesives, etc., has excellent productivity, has excellent dispersibility of additives according to each application, can adhere in a wide temperature range from low temperature to high temperature, and can contribute to reduction of environmental load. It is an object of the present invention to provide a resin and a method for producing the same.

The first gist of the present invention is a polyester resin having an unsaturated double bond, wherein the THF insoluble content (1) of the polyester resin is 5% by mass or less and less than 0.15% by mass of a radical reaction initiator. The polyester resin has a THF insoluble content (2) of 10% by mass or more after being crosslinked with the polyester resin having a softening temperature of 100 ° C.
The second gist of the present invention is a method for producing a polyester resin in which a polyvalent carboxylic acid and a polyvalent alcohol are polymerized in the presence of an antioxidant and a catalyst, wherein the catalyst is a group Titanium of Group 4A of the periodic table. Compound X containing at least one selected from the group consisting of elements, Compound Y containing at least one selected from the group consisting of Group 1A and Group 2A of the Periodic Table, manganese, iron, and cobalt, and phosphorus compound Z. It is in the method of producing a polyester resin which is a catalyst containing.

By using the polyester resin of the present invention and its manufacturing method, it is excellent in productivity, excellent dispersibility of additives according to each application, can be fixed in a wide temperature range from low temperature to high temperature, and contributes to reduction of environmental load. A toner or adhesive that can be obtained is obtained.

The polyester resin of the present invention is a polyester resin having an unsaturated double bond, and is a radical reaction initiator having a THF insoluble content (1) of the polyester resin of 5% by mass or less and less than 0.15% by mass. The THF insoluble content (2) after cross-linking with the polyester resin having a softening temperature of 100 ° C. is 10% by mass or more.
In the present invention, the polyester resin having an unsaturated double bond is a polyester resin having an intercarbon double bond in the molecule, and has an unsaturated double bond in the main chain and / or side chain of the polyester resin. Is.

The unsaturated polyester resin of the present invention crosslinks unsaturated double bonds in the polyester resin to generate intermolecular carbon-carbon bonds, so that a part of the resin after the crosslinking reaction is not dissolved in THF. It changes to a dense cross-linking component (THF insoluble component), and a part of it changes to a low-cross-linking component that dissolves in THF, and the rest remains unreacted.
As a result, the resin obtained by the cross-linking reaction contains a THF-insoluble component (cross-linking component insoluble in THF) and a THF-soluble component (cross-linking component dissolved in THF and unreacted polyester resin). Since the THF insoluble component is crosslinked at a high density, it exerts an action of imparting higher elasticity to the toner, and the high temperature offset resistance of the toner is further improved. In other words, it is a material that is excellent in fixing and adhesion on the high temperature side.
In order to have an unsaturated double bond in the main chain and / or side chain of the polyester resin, for example, a polycarboxylic acid having an unsaturated double bond may be subjected to a polycondensation reaction using a polyol. ..
Further, the THF insoluble content (1) of the polyester resin of the present invention needs to be 5% by mass or less.

If the THF insoluble content (1) exceeds 5% by mass, the amount of resin discharged tends to decrease and the resin productivity decreases. The THF insoluble content (1) is preferably less than 4.5%.
Further, in the present invention, the THF insoluble content (2) after cross-linking the polyester resin with the polyester resin having a softening temperature of 100 ° C. with a radical reaction initiator of less than 0.15% by mass is 10% by mass or more. is necessary. If the THF insoluble content (2) is less than 10% by mass, fixing and adhesion at high temperature will be insufficient. The THF insoluble content (2) is preferably 10% by mass or more and less than 30% by mass from the viewpoint of fixing in a wide range from low temperature to high temperature.
The THF insoluble content (1) and the THF insoluble content (2) are values measured by the following methods.

<THF insoluble matter (1)>
Put about 2 g of Celite 545 (manufactured by Kishida Chemical Co., Ltd.) into a cylindrical glass filter 1GP100 (manufactured by Shibata Chemical Co., Ltd.) with an inner diameter of 3.5 cm, and keep the glass filter until the height of the layer of Celite 545 does not change. I tapped it on the cork table. This operation was repeated four times, and the glass filter was filled with Celite 545 so that the height of the layer of Celite 545 was 2 cm from the filter surface.
The glass filter filled with Celite 545 was dried at 105 ° C. for 3 hours or more, and the weight thereof was weighed (Yg). Next, about 0.5 g of the sample was placed in an Erlenmeyer flask and weighed (Xg), then 50 ml of THF (tetrahydrofuran) was added, and the sample was heated in a water bath at 70 ° C. for 3 hours to dissolve the sample under reflux with THF. I let you.
This solution was put into a glass filter filled with Celite 545 and suction filtered. The glass filter that captured the THF insoluble matter was dried at 80 ° C. for 3 hours or more, and the weight thereof was weighed (Zg) to determine the THF insoluble matter (1) according to the following formula.
THF insoluble content (1) = {(ZY) / X} x 100 (mass%)

<THF insoluble matter (2)>
10 parts by mass of the radical initiator was added to 90 parts by mass of a mold release agent (SP-0160 manufactured by Nippon Seiko Co., Ltd.) that was melted by heating to 75 ° C., and the obtained mixture was cooled, pulverized, and released. A radical reaction initiator (I) diluted with a mold was prepared.
Next, an unsaturated polyester resin: 90 parts by mass and a polyester resin having a softening temperature of 100 ° C.: 10 parts by mass were supplied to a twin-screw extruder (PCM-29: L / D = 30 manufactured by Ikegai Co., Ltd.) to the outside. The mixture was melt-mixed at a temperature setting of 180 ° C. and a residence time of about 1.5 minutes, cooled, and then pulverized. A radical reaction initiator (I) is added to this pulverized product as an additive diluted with a release agent, mixed, and supplied to the twin-screw extruder at an external temperature setting of 180 ° C. and a residence time of about 3 minutes. Melt kneading was performed to obtain a polyester resin. The resin after kneading in the presence of this radical initiator is defined as a THF insoluble component (2) as measured by the same method as in the THF insoluble component (1).

Further, the polyester resin having an unsaturated double bond of the present invention contains at least one selected from the group consisting of a repeating unit derived from a polyvalent carboxylic acid having a branched structure and a repeating unit derived from a polyhydric alcohol having a branched structure. Is preferable.
Examples of the polyvalent carboxylic acid having a branched structure include trimellitic acid, trimellitic anhydride, 1,3,5-benzenetricarboxylic acid, pyromellitic acid, pyromellitic anhydride, and diphenyl-3,3', 4,4'. -Tetracarboxylic acid dianhydride and the like are mentioned, and trimellitic anhydride, pyromellitic anhydride and diphenyl-3,3', 4,4'tetracarboxylic acid dianhydride are preferable from the viewpoint of high reactivity.
Examples of the polyhydric alcohol having a branched structure include glycerin, trimethylolpropane, trimethylolethane, erythritol, pentaerythritol, sorbitol, etc., and trimethylolpropane, erythritol, etc. in terms of suppressing a highly reactive and rapid gelation reaction. Pentaerythritol is preferred.

Further, the polyester resin of the present invention preferably has a softening temperature (T4) of 130 ° C. or higher and 180 ° C. or lower. If the softening temperature is less than 130 ° C., the amount of the initiator for increasing the THF insoluble content (2) to 10% or more tends to increase, and the environmental load tends to increase. When the softening temperature exceeds 180 ° C., the THF insoluble content (1) tends to exceed 5 wt%, the discharge amount of the resin tends to decrease, and the resin productivity tends to be low.

The unsaturated polyester resin of the present invention can be obtained, for example, by polymerizing a polycarboxylic acid having an unsaturated double bond and a polyol through an esterification reaction, a transesterification reaction, and a condensation reaction.
As the polycarboxylic acid having an unsaturated double bond, a dicarboxylic acid compound such as maleic acid, fumaric acid, citraconic acid, glutaconic acid, itaconic acid, anhydrides of these acids and alkyl esters is preferable, and among these, dicarboxylic acid compounds are preferable. From the viewpoint of reactivity, at least one selected from the group consisting of fumaric acid, maleic acid, anhydrides of those acids and alkyl esters is preferable, and fumaric acid is more preferable.
From the viewpoint of reactivity, the amount of the polycarboxylic acid component having an unsaturated double bond is preferably less than 1 to 60 mol parts, more preferably less than 1 to 50 mol parts, 1 out of 100 mol parts of the polycarboxylic acid component. It is particularly preferably less than ~ 45 mol parts, most preferably less than 1-40 mol parts.

Examples of polycarboxylic acids other than polycarboxylic acids having unsaturated double bonds include terephthalic acid, isophthalic acid, orthophthalic acid, sebacic acid, adipic acid, succinic acid, glutaric acid, metaconic acid, citraconic acid, and glutaconic acid. Polycarboxylic acids such as cyclohexanedicarboxylic acid, alkenylsuccinic acid, malonic acid, linolenic acid, trimellitic acid, pyromellitic acid; alkyl esters of these dicarboxylic acids (monomethyl ester, dimethyl ester, monoethyl ester, diethyl ester, monobutyl Esters, dibutyl esters, etc.); Examples thereof include acid anhydrides of these polycarboxylic acids. These polycarboxylic acids can be used alone or in combination of two or more.
Of these, terephthalic acid, isophthalic acid, or alkyl esters thereof are preferred. In particular, terephthalic acid and isophthalic acid are preferable because they have high reactivity with carboxylic acids having unsaturated double bonds and tend to have good toner storage stability.

The amount of the polycarboxylic acid component other than the polycarboxylic acid having an unsaturated double bond is preferably 50 mol parts or more out of 100 mol parts of the polycarboxylic acid component. When this content is 50 mol parts or more, the production stability of the polyester resin tends to be good. From the viewpoint of storage stability, the lower limit of this content is more preferably 55 mol parts or more, further preferably 60 mol parts or more, particularly preferably 65 mol parts or more, and most preferably 70 mol parts or more. The upper limit is preferably 99 mol parts or less from the viewpoint of reactivity.

Examples of the polyol include ethylene glycol, 1,3-propanediol, 1,2-propanediol, 1,3-butanediol, 2,3-butanediol, 1,4-butanediol, diethylene glycol, and 2-methyl. -1,3-propanediol, triethylene glycol, neopentyl glycol, 1,6-hexanediol, 1,8-octanediol, D-isosorbide, L-isosorbide, isomannide, 1,2-cyclohexanedimethanol, 1, 4-Cyclohexanedimethanol, 1,4-cyclohexanediol, sorbitol, 1,2,3,6-hexanetetralol, 1,4-sorbitan, erythritol, pentaerythritol, dipentaerythritol, erythritan, 1,2,4- Butantriol, 1,2,5-pentanetriol, glycerol, 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, trimethylpropane, mannitol, 1,10-decanediol, 1,12-Dodecanediol, polyethylene glycol, hydride bisphenol A, hydride bisphenol A ethylene oxide adduct and propylene oxide adduct, polyoxyethylene- (2.0) -2,2-bis (4-hydroxyphenyl) Propane, polyoxypropylene- (2.0) -2,2-bis (4-hydroxyphenyl) propane, polyoxypropylene (2.2) -polyoxyethylene- (2.0) -2,2-bis ( 4-Hydroxyphenyl) propane, polyoxypropylene (6) -2,2-bis (4-hydroxyphenyl) propane, polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane, poly Oxypropylene- (2.4) -2,2-bis (4-hydroxyphenyl) propane, polyoxypropylene (3.3) -2,2-bis (4-hydroxyphenyl) propanspiroglycol, cyclodecanedimethanol , Tricyclodecanedimethanol, tripentaerythritol, trehalose, cyclodextrin compound, lignin, lignophenol and the like, and these can be used alone or in combination of two or more.

Among these, a divalent polyol is preferable from the viewpoint of toner storage stability. Among the divalent polyols, ethylene glycol, neopentyl glycol, 1,2-propanediol, 1,4-cyclohexanedimethanol, D-isosorbide, L-isosorbide, isomannide, 1,2-cyclohexanedimethanol, sorbitol, 1,2,3,6-hexanetetralol, 1,4-sorbitan, erythritol, pentaerythritol, dipentaerythritol, erythritol, trimethylolethane, and trimethylolpropane are preferable.

Further, in order to carry out the crosslinking reaction of the THF insoluble content (2) to 10% or more with a small amount of the initiator added, it is preferable that trimethylolpropane, 1,4-cyclohexanedimethanol and isosorbide are copolymerized. In particular, the unsaturated polyester resin in which trimethylolpropane is copolymerized in an amount of 0.1 to 20 mol is easy to control the THF insoluble content (2) to 10% or more even if the amount of the initiator added is small, and the result is derived from the initiator. The amount of residue can be reduced and the environmental load can be suppressed.

From the viewpoint of the balance between the glass transition temperature (Tg) and the softening temperature (T4), the total amount of the polyol is preferably 150 mol parts or less, more than 80 mol parts, and 120 mol with respect to 100 mol parts of the polycarboxylic acid component. Part or less is particularly preferable. The molar ratio of the polycarboxylic acid to the polyol (polypoly / polycarboxylic acid) is preferably larger than that of the polycarboxylic acid from the viewpoint that the molecular weight of the polyester can be easily adjusted by distilling off the alcohol.

Further, in the present invention, a monovalent carboxylic acid or a monohydric alcohol may be used.
Examples of the monovalent carboxylic acid include aromatic carboxylic acids having 30 or less carbon atoms such as benzoic acid and p-methylbenzoic acid, aliphatic carboxylic acids having 30 or less carbon atoms such as stearic acid and behenic acid, and cinnamic acid. , Oleic acid, linoleic acid, linolenic acid and the like.
Examples of monohydric alcohols include aromatic alcohols having 30 or less carbon atoms such as benzyl alcohol, and fatty alcohols having 30 or less carbon atoms such as oleyl alcohol, lauryl alcohol, cetyl alcohol, stearyl alcohol, and behenyl alcohol.

From the viewpoint of the balance between the glass transition temperature (Tg) and the softening temperature (T4), the total amount of the polyol is preferably 150 mol parts or less, more than 80 mol parts, and 120 parts with respect to 100 mol parts of the polycarboxylic acid component. The molar part or less is particularly preferable. The molar ratio of the polycarboxylic acid to the polyol (polypoly / polycarboxylic acid) according to the resin 1 is preferably more than the polycarboxylic acid from the viewpoint that the molecular weight of the polyester can be easily adjusted by distilling off the alcohol. ..

Further, in the present invention, a polymerization catalyst such as titanium tetrabutoxide, dibutyltin oxide, tin acetate, zinc acetate, tin disulfide, antimony trioxide, germanium dioxide and the like can be used for polymerization. If it is desired to suppress coloring of the resin, compound X containing at least one selected from the group consisting of group 4A titanium elements of the periodic table, group 1A and 2A of the periodic table, manganese, iron, and cobalt It is preferable to use a catalyst containing compound Y containing at least one selected from the group consisting of, and phosphorus compound Z.

The polymerization temperature is preferably in the range of 180 to 290 ° C. When the polymerization temperature is 180 ° C. or higher, the productivity tends to be good, and when the polymerization temperature is 290 ° C. or lower, the decomposition of the resin and the by-production of volatile substances that cause odors tend to be suppressed. The lower limit of the polymerization temperature is more preferably 200 ° C. or higher, and particularly preferably 220 ° C. or higher. The upper limit of the polymerization temperature is preferably 270 ° C. or lower.

Further, in the present invention, it is preferable to add an antioxidant for the purpose of increasing the productivity of the resin and obtaining the polymerization stability. Examples of antioxidants include hydroquinone, methylhydroquinone, tert-butylcatechol, and hindered phenol compounds (eg, product names Adecastab AO-30, AO-60, AO-330, non-flex Alba manufactured by Seiko Kagaku Co., Ltd.). Can be mentioned. From the viewpoint of reducing the THF insoluble content (1), it is preferable to use two or more types in combination.

Further, the polyester resin having an unsaturated double bond of the present invention can be crosslinked with a polyester resin other than the polyester resin having an unsaturated double bond with a radical reaction initiator.
As the polyester resin other than the polyester resin having an unsaturated double bond, a polyester resin having a softening temperature of 80 ° C. or higher and 130 ° C. or lower is preferable. When the softening temperature is 80 ° C. or higher and 130 ° C. or lower, the material dispersibility during kneading in the presence of an initiator is good. If the softening temperature is less than 80 ° C., the dispersibility of the material tends to be low, and the glass transition temperature tends to decrease, so that the resin tends to become sticky in the summer and the storage stability tends to deteriorate. Further, when the softening temperature exceeds 130 ° C., fixing and adhesion on the low temperature side are likely to be hindered.

The form of the cross-linking reaction is, for example, a reaction in which an unsaturated double bond in a polyester resin is reacted by a radical addition reaction, a cation addition reaction, an anion addition reaction, or the like to generate an intermolecular carbon-carbon bond, or in a polyester resin. Examples thereof include the formation of intermolecular bonds by a condensation reaction, a double addition reaction, an ester exchange reaction, or the like of a polyvalent carboxylic acid group, a polyhydric alcohol group, a polyvalent epoxy group, or a polyvalent isocyanate group. Of these, a reaction in which an unsaturated double bond in a polyester resin is reacted by a radical addition reaction, a cation addition reaction, an anion addition reaction, or the like to generate an intermolecular carbon-carbon bond is preferable.

The reaction of reacting an unsaturated double bond in a polyester resin by a radical addition reaction, a cation addition reaction, an anion addition reaction, or the like to generate an intermolecular carbon-carbon bond is carried out by a thermal reaction, a photoreaction, a redox reaction, or the like. It can be advanced depending on the active species generated. Of these, a thermal reaction is preferable, and a radical reaction is particularly preferable. As the radical reaction, a radical reaction initiator may be used, or a radical reaction initiator may not be used. In particular, the method using a radical reaction initiator is preferable from the viewpoint of effectively causing the cross-linking reaction.

As the radical reaction initiator, an azo compound or an organic peroxide is used. Of these, organic peroxides are preferred because they have high initiator efficiency and do not produce cyanide by-products.

Examples of the organic peroxide include benzoyl peroxide, di-t-butyl peroxide, t-butyl cumyl peroxide, dicumyl peroxide, α, α-bis (t-butyl peroxy) diisopropylbenzene, 2, 5-Dimethyl-2,5-bis (t-butylperoxy) hexane, di-t-hexylperoxide, 2,5-dimethyl-2,5-di-t-butylperoxyhexin-3, Acetyl peroxide, isobutyryl peroxide, octaninol peroxide, decanolyl peroxide, lauroyl peroxide, 3,3,5-trimethylhexanoyl peroxide, m-toluyl peroxide, t-butylperoxyisobutyrate, t-Butylperoxyneodecanoate, cumylperoxyneodecanoate, t-butylperoxy2-ethylhexanoate, t-butylperoxy3,5,5-trimethylhexanoate, t-butylper Examples thereof include oxylaurate, t-butylperoxybenzoate, t-butylperoxyisopropyl carbonate, t-butylperoxyacetate and the like.

Among these, a radical reaction initiator having a high hydrogen abstraction ability is particularly preferable because the cross-linking reaction proceeds efficiently and the amount used can be small. Preferred examples of radical reaction initiators having high hydrogen abstraction ability include benzoyl peroxide, di-t-butyl peroxide, t-butylcumylper oxide, dicumylperoxide, α, α-bis (t-butylperoxy). ) Diisopropylbenzene, 2,5-dimethyl-2,5-bis (t-butylperoxy) hexane, di-t-hexylperoxide and the like. The amount of the radical reaction initiator used is preferably 0.01 to 2 parts by mass with respect to 100 parts by mass of the polyester resin.

When the amount of the radical reaction initiator used is 0.01 parts by mass or more, the cross-linking reaction tends to proceed easily, and when it is 2 parts by mass or less, the residue derived from the initiator is reduced but the odor is good. It tends to be. The amount used is more preferably 0.5 parts by mass or less, further preferably 0.25 parts by mass or less, and particularly preferably 0.15 parts by mass or less.

In addition, by diluting the radical reaction initiator with a diluent and adding it, there is a tendency that the self-induced decomposition of the radical reaction initiator can be suppressed, high safety can be ensured during the production of the polyester resin, and the radicals due to the self-induced decomposition Wasteful consumption of the reaction initiator can be suppressed, and the amount of the radical reaction initiator used can be reduced.
As the diluent for the radical reaction initiator, a release agent is particularly preferable. By containing the release agent in the polyester resin for toner in advance, the dispersibility of the release agent becomes better than when the release agent is added at the time of toner formation.

As the mold release agent, a hydrocarbon-based mold release agent is preferable, and for example, an aliphatic hydrocarbon-based wax such as low molecular weight polyethylene, low molecular weight polypropylene, microcrystalline wax, and paraffin wax; an aliphatic hydrocarbon such as polyethylene oxide wax. Oxides of waxes; or block compounds thereof and the like.
Among these, those having a melting point of 120 ° C. or lower are preferable because they can be easily mixed with the radical reaction initiator and tend to further improve the low temperature fixability of the toner. Paraffin wax is most preferable as a mold release agent having a melting point of 120 ° C. or lower, and HNP series manufactured by Nippon Seiko Co., Ltd .: For example, HNP-3 (melting point 64 ° C.), HNP-5 (melting point 62 ° C.), HNP-9, 10 (melting point 75 ° C.), HNP-11 (melting point 68 ° C.), HNP-12 (melting point 67 ° C.), HNP-51 (melting point 77 ° C.), SP series: for example, SP-0165 (melting point 74 ° C.), SP- 0160 (melting point 71 ° C.), SP-0145 (melting point 62 ° C.), HNP-3 (melting point 64 ° C.), FT series: FT-0070 (melting point 72 ° C.), FT-0165 (melting point 73 ° C.) and the like.

Examples of the method for preparing the radical reaction initiator diluted with the release agent include a method of mixing a liquid radical reaction initiator with a mold release agent liquefied by heating, and a method of mixing a liquid radical reaction initiator with a solid radical reaction initiator. Examples include a method of dissolving and mixing the radical reaction, and a method of impregnating a solid mold release agent with a liquid radical reaction initiator. Among them, from the viewpoint of uniformity and dispersibility of the radical reaction initiator, a method of mixing a liquid radical reaction initiator with a liquefied mold release agent and a radical reaction initiator which is a solid with the liquefied mold release agent. A method of dissolving the radical is preferable.

The mixing ratio of the unsaturated polyester resin to the other polyester resin is preferably 70/30 to 99/1 (mass mixing ratio). When this mixing ratio is within the above ratio range, the balance between the fixing strength on the low temperature side and the fixing strength on the high temperature side of the toner tends to be good.

When the resin is melt-kneaded in the presence of the radical reaction initiator, the polyester resin in the molten state immediately after the polymerization may be kneaded and the radical reaction initiator may be added, or the resin may be cooled and solidified after the polymerization. After obtaining the polyester resin of the above, the resin obtained by melt-kneading with the resin may be crushed, and further, a radical reaction initiator may be added and melt-kneaded again.
As an apparatus for performing melt-kneading, an apparatus similar to the polycondensation step of polyester resin may be used, but a melt-mixing apparatus is preferable from the viewpoint of uniformly mixing the polyester resin and the radical reaction initiator in a short time.

Examples of the melt mixer include a single shaft extruder, a twin shaft extruder, a continuously sealed mixer, a gear extruder, a disc extruder and a roll mill extruder, a static mixer and the like, and a continuous melt mixer; a Banbury mixer, a Brabender mixer, etc. And a batch closed type melting and mixing device such as a harke mixer. Among these, a continuous melt mixing device is preferable because the radical reaction initiator can be efficiently dispersed in the polyester resin in a short time. Further, when a radical reaction initiator is added to the polyester resin in the molten state immediately after polymerization to carry out the crosslinking reaction, the melt mixing apparatus is preferably connected to the polycondensation reaction kettle.

Next, the toner using the polyester resin of the present invention will be described. The toner of the present invention can be obtained by blending the polyester resin with additives such as a colorant, a charge control agent, a mold release agent, a flow modifier, and a magnetic material, if necessary.

Coloring agents include carbon black, niglocin, aniline blue, phthalocyanine blue, phthalocyanine green, Hansa yellow, rhodamine dyes, chrome yellow, quinacridone, benzidine yellow, rose bengal, triallyl methane dyes, monoazo, disazo, Examples thereof include condensed azo dyes and pigments. These dyes and pigments can be used alone or in admixture of two or more. In the case of full-color toner, yellow includes benzidine yellow, monoazo dye, condensed azo dye, magenta quinacridone, rhodamine dye, monoazo dye, and cyan include phthalocyanine blue. The content of the colorant is preferably 2 to 10% by mass in the toner from the viewpoint of the color tone, image density, and thermal characteristics of the toner.

Examples of the charge control agent include a quaternary ammonium salt as a positive charge control agent, a basic or electron donating organic substance, and the like, and as a negative charge control agent, metal chelates, metal-containing dyes, acidic or electron attracting properties. Organic substances and the like. In the case of color toners, it is important that the charge control agent is colorless or pale and that there is no color disturbance to the toner, for example, metal salts, metal complexes, amides of salicylic acid or alkylsalicylic acid with chromium, zinc, aluminum, etc. Examples thereof include compounds, phenol compounds and naphthol compounds. Further, a styrene-based, acrylic acid-based, methacrylic acid-based, or vinyl polymer having a sulfonic acid group may be used as the charge control agent.
The content of the charge control agent is preferably 0.5 to 5% by mass in the toner. When the content of the charge control agent is 0.5% by mass or more, the charge amount of the toner tends to be at a sufficient level, and when it is 5% by mass or less, the decrease in the charge amount due to the aggregation of the charge control agent is suppressed. Tend to be.

As the release agent, carnauba wax, rice wax, beeswax, polypropylene wax, polyethylene wax, synthetic ester wax, paraffin wax, etc. are used in consideration of the release property, storage stability, fixability, color development property, etc. of the toner. A fatty acid amide, a silicone wax or the like can be appropriately selected and used. These can be used alone or in combination of two or more.
The melting point of the release agent can be appropriately selected and used in consideration of the above toner performance. Since the content of the release agent affects the above-mentioned toner performance, it is preferably 0.3 to 15% by mass in the toner.

Additives such as fluidity modifiers include fine powders of silica, alumina, titania and other fluidity improvers, magnetite, ferrite, cerium oxide, strontium titanate, conductive titania and other inorganic fine powders, styrene resin and acrylic. Examples thereof include resistance modifiers such as resins and lubricants, which are used as internal additives or external additives.

The content of these additives is preferably 0.05 to 10% by mass in the toner. When the content of these additives is 0.05% by mass or more, the performance modifying effect of the toner tends to be sufficiently obtained, and when the content is 10% by mass or less, the image stability of the toner tends to be good. is there.

Further, as the binder resin, a binder resin other than the polyester resin of the present invention may be used as long as the effect of the present invention is not impaired. For example, a styrene resin, a styrene-acrylic resin, a cyclic olefin resin, or a methacrylic acid resin. , Epoxy resin and the like, and can be used alone or in combination of two or more.

The toner of the present invention can be used as any of a magnetic one-component developer, a non-magnetic one-component developer, and a two-component developer.

Regarding the method for producing a toner of the present invention, after mixing the above-mentioned binder resin, additives, etc., melt-kneading is performed with a twin-screw extruder or the like, coarse pulverization, fine pulverization, and classification are performed, and if necessary, inorganic particles are obtained. A method of manufacturing by external addition treatment (crushing method), the above-mentioned binder resin and compound are dissolved and dispersed in a solvent, granulated in an aqueous medium, the solvent is removed, and the solvent is washed and dried. Examples thereof include a method (chemical method) in which particles are obtained and, if necessary, externally treated with inorganic particles to produce the particles.

The particle size of the toner of the present invention is preferably in the range of 3 to 15 μm, more preferably in the range of 5 to 10 μm. This tends to improve productivity when it is 3 μm or more. Further, when the particle size is 15 μm or less, high image quality tends to be obtained.

Hereinafter, the present invention will be specifically described with reference to Examples. However, the present invention is not limited to the following examples. The evaluation method of the polyester resin shown in this example is as follows.

"Measurement / evaluation method"
<Measurement of glass transition temperature (Tg)>
The Tg of the polyester resin was measured from the intersection of the baseline of the chart and the tangent line of the endothermic curve at a heating rate of 5 ° C./min using a differential scanning calorimeter (“DSC-60” manufactured by Shimadzu Corporation). .. As a measurement sample, 10 mg ± 0.5 mg was weighed in an aluminum pan, thawed at 100 ° C. above the glass transition temperature for 10 minutes, and then rapidly cooled with dry ice.

<Measurement of softening temperature (T4)>
The polyester resin T4 is a resin sample using a flow tester (manufactured by Shimadzu Corporation, “CFT-500D”) under a nozzle of 1 mmφ × 10 mm, a load of 294 N, and a constant temperature temperature rise of 3 ° C./min. The temperature at which 4 mm in 1.0 g flowed out was measured and used as the softening temperature.

<Measurement of acid value (AV)>
Approximately 0.2 g of polyester resin was precisely weighed in an Erlenmeyer flask with branches (A (g)), 10 mL of benzyl alcohol was added, and the polyester resin was dissolved by heating in a heater at 230 ° C. for 15 minutes under a nitrogen atmosphere. After allowing to cool to room temperature, 10 mL of benzyl alcohol, 20 mL of chloroform, and several drops of phenolphthalein solution were added and titrated with a KOH solution of 0.02 (titration = B (mL), titer of KOH solution = p). .. The blank measurement was performed in the same manner (titration = C (mL)), and the calculation was performed according to the following formula.
Acid value (mgKOH / g) = {(BC) x 0.02 x 56.11 x p} / A

<Molecular weight: mass average molecular weight (Mw), peak molecular weight (Mp)>
By the GPC method, the mass average molecular weight (Mw) and the peak molecular weight (Mp) were determined by standard polystyrene conversion from the retention time corresponding to the peak value of the obtained dissolution curve. The peak value of the dissolution curve is a point where the dissolution curve shows a maximum value, and when there are two or more maximum values, the dissolution curve gives a maximum value.
Equipment: HLC8020 manufactured by Toyo Soda Industries Co., Ltd.
Column: Three TSKgelGMHXL (column size: 7.8 mm (ID) x 30.0 cm (L)) manufactured by Toyo Soda Industries Co., Ltd. are connected in series. Oven temperature: 40 ° C.
Eluent: THF
Sample concentration: 4 mg / 10 mL
Filtration conditions: Filter the sample solution with a 0.45 μm Teflon® membrane filter Flow rate: 1 mL / min Injection volume: 0.1 mL
Detector: RI
Standard polystyrene sample for preparing calibration lines: TSK standard manufactured by Toyo Soda Kogyo Co., Ltd., A-500 (molecular weight 5.0 × 102), A-2500 (molecular weight 2.74 × 103), F-2 (molecular weight 1.96) × 104), F-20 (molecular weight 1.9 × 105), F-40 (molecular weight 3.55 × 105), F-80 (molecular weight 7.06 × 105), F-128 (molecular weight 1.09 × 106) ), F-288 (molecular weight 2.89 × 106), F-700 (molecular weight 6.77 × 106), F-2000 (molecular weight 2.0 × 107).

<Manufacturing method of polyester resins 1 to 10>
The polyvalent carboxylic acid, polyhydric alcohol, additive, and catalyst having the charged composition shown in Table 1 were charged into a reaction vessel equipped with a distillation column. Then, the temperature was started to rise, and the temperature in the reaction system was heated to 260 ° C., and this temperature was maintained, and the esterification reaction was carried out until water was not distilled from the reaction system. Next, while maintaining the temperature inside the reaction system after cooling to 220 ° C., the inside of the reaction vessel was reduced to 0.5 kPa · abs and stirred at 200 rpm to carry out the condensation reaction while distilling the polyhydric alcohol from the reaction system. did.
At the end of the polymerization, when the stirring torque of 4 kg-m is reached at 50 rpm, the stirring of the reactor is stopped, the inside of the apparatus is set to normal pressure, the inside of the apparatus is pressurized with nitrogen, and the reaction product is taken out from the lower part of the apparatus to 50 or less. The mixture was cooled to obtain a polyester resin (resin 1 to 10).
For the polyester resin (resin B) having a softening temperature of 100 ° C., the inside of the apparatus is made normal pressure with nitrogen during the condensation reaction, about 3 g of the resin is sampled from the reaction vessel, the resin is cooled to room temperature, and then softened. The temperature was measured and sampling was repeated until the softening temperature shown in Table 1 was reached to proceed with the polymerization.
The glass transition temperature, softening temperature, acid value, and molecular weight of the obtained polyester resin were measured, and the results are shown in Table 1.

(Example 1)
Next, using the resin 1 in Table 1, the THF-insoluble component (1) of the resin 1, the gel 1, the THF-insoluble component after kneading the resin A, and the THF after the cross-linking reaction between the resin 1 and the resin B are performed. The insoluble matter (2) was determined.

<THF insoluble matter (1)>
Put about 2 g of Celite 545 (manufactured by Kishida Chemical Co., Ltd.) into a cylindrical glass filter 1GP100 (manufactured by Shibata Chemical Co., Ltd.) with an inner diameter of 3.5 cm, and keep the glass filter until the height of the layer of Celite 545 does not change. I tapped it on the cork table. This operation was repeated four times, and the glass filter was filled with Celite 545 so that the height of the layer of Celite 545 was 2 cm from the filter surface. The glass filter filled with Celite 545 was dried at 105 ° C. for 3 hours or more, and the weight thereof was weighed (Yg). Next, about 0.5 g of the sample was placed in an Erlenmeyer flask and weighed (Xg), then 50 ml of THF (tetrahydrofuran) was added, and the sample was heated in a water bath at 70 ° C. for 3 hours to dissolve the sample under reflux with THF. I let you. This solution was put into a glass filter filled with Celite 545 and suction filtered. The glass filter that captured the THF insoluble matter was dried at 80 ° C. for 3 hours or more, the weight was weighed (Zg), and the THF insoluble matter was calculated according to the following formula.
THF insoluble = {(Z-Y) / X} x 100 (mass%)

<THF insoluble content after kneading the resin>
1: 100 parts by mass of resin was supplied to a twin-screw extruder (PCM-29: L / D = 30 manufactured by Ikegai Co., Ltd.), melt-mixed at an outside temperature setting of 120 ° C., and stayed for about 1.5 minutes. Using the polyester resin crushed after cooling, the THF insoluble content after kneading of the resin A was evaluated according to the following procedure. The smaller the amount of THF insoluble after kneading, the better the correlation with the tendency to improve the pigment dispersion in the subsequent process. That is, if a large amount of THF insoluble matter is present in the kneaded resin, pigment dispersion tends to be poor.
Put about 2 g of Celite 545 (manufactured by Kishida Chemical Co., Ltd.) into a cylindrical glass filter 1GP100 (manufactured by Shibata Chemical Co., Ltd.) with an inner diameter of 3.5 cm, and keep the glass filter until the height of the layer of Celite 545 does not change. I tapped it on the cork table. This operation was repeated four times, and the glass filter was filled with Celite 545 so that the height of the layer of Celite 545 was 2 cm from the filter surface. The glass filter filled with Celite 545 was dried at 105 ° C. for 3 hours or more, and the weight thereof was weighed (Yg). Next, about 0.5 g of the sample was placed in an Erlenmeyer flask and weighed (Xg), then 50 ml of THF (tetrahydrofuran) was added, and the sample was heated in a water bath at 70 ° C. for 3 hours to dissolve the sample under reflux with THF. I let you. This solution was put into a glass filter filled with Celite 545 and suction filtered. The glass filter that captured the THF insoluble matter was dried at 80 ° C. for 3 hours or more, the weight was weighed (Zg), and the THF insoluble matter was calculated according to the following formula.
THF insoluble = {(Z-Y) / X} x 100 (mass%)

<THF insoluble matter (2)>
A mold release agent (manufactured by Nippon Seikan Co., Ltd.) in which 10 parts by mass of 2,5-dimethyl-2,5-bis (t-butylperoxy) hexane (Nichiyu Co., Ltd.) was heated to 75 ° C. and melted. SP-0160) 90 parts by mass, the resulting mixture was cooled and pulverized to prepare a radical reaction initiator (I) diluted with a release agent. The radical reaction initiator (I) is used as an additive.
Next, 1:90 parts by mass of resin and 12:10 parts by mass of resin were supplied to a twin-screw extruder (PCM-29: L / D = 30 manufactured by Ikekai Co., Ltd.), and the outside temperature was set to 180 ° C., about 1. The mixture was melt-mixed with a residence time of 5 minutes, cooled, and then pulverized. The radical reaction initiator (I) as an additive diluted with a release agent is added to the pulverized product in the amounts shown in Table 2, mixed, and supplied to the twin-screw extruder to set an external temperature of 180 ° C., about 3 A polyester resin was obtained by melt-kneading with a residence time of minutes. The gel amount (gel 2) of the resin obtained with each additive amount was evaluated, and the amount of the additive material at which the gel amount was 10 wt% or more was evaluated from the correlation between the additive amount and the gel amount. When the amount of the additive is large, the low molecular weight volatile components of the additive-derived residue increase, so that it is necessary to carry out the crosslinking reaction in the smallest possible amount. Gel 2 was measured by the same measurement method as gel 1.

(Examples 2 to 7, Comparative Examples 1 to 3)
In Examples 2 to 7 and Comparative Examples 1 to 3, the resin 1 was changed to resins 2 to 11 as shown in Table 2, and the same evaluation as in Example 1 was performed.

Additive AO-30: 4,4', 4''-(1-methylpropanyl-3-ylidene) tris (6-tert-butyl-m-cresol)
AO-60: Pentaerythritol tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate]
AO-330: 1,3,5-tris (3,5-di-tert-butyl-4-hydroxyphenylmethyl) -2,4,6-trimethylbenzene
TBC: 4-tert-Butylcatechol Non-Flex Alba: 2,5-Di-tert-butylhydroquinone
Catalyst TBT: Tetra-n-butoxytitanium NC2500: Titanium-based catalyst manufactured by Mitsubishi Chemical Corporation

As is clear from the results in Table 2, in each of the examples, the THF insoluble content (1) of the polyester resin is 5% by mass or less, the productivity and material dispersibility are good, and less than 0.15% by mass. A polyester resin having a THF insoluble content (2) of 10% by mass or more after being crosslinked with a polyester resin having a softening temperature of 100 ° C. and a small amount of residue derived from the initiator can be obtained.
On the other hand, as is clear from the results in Table 2, in the case of Comparative Example 1, THF insoluble after cross-linking with a polyester resin having a softening temperature of 100 ° C. with a radical reaction initiator (I) of 0.14% by mass or more. Minute (2) does not exceed 10% by mass.
In the case of Comparative Example 2, with the radical reaction initiator (I) of 0.14% by mass or more, gelation rapidly occurred and solidified, and the amount of THF insoluble matter (2) could not be controlled.
In the case of Comparative Example 3, with the radical reaction initiator (I) of 0.14% by mass or more, the THF insoluble content (2) reaches 30% by mass although it becomes 10% by mass or more, and the THF insoluble content is reached. The reproduction stability of (2) was poor.

In the case of Comparative Example 4, although the THF insoluble content (2) was 10% by mass or more, the reproduction stability of the THF insoluble content (2) was very poor.

Claims (6)

A polyester resin having an unsaturated double bond, the polyester resin having a THF insoluble content (1) of 5% by mass or less, a radical reaction initiator of less than 0.15% by mass, and a softening temperature of 100 ° C. A polyester resin having a THF insoluble content (2) of 10% by mass or more after being crosslinked with the resin. Claim 1 in which the polyester resin having an unsaturated double bond comprises at least one selected from the group consisting of a repeating unit derived from a polyvalent carboxylic acid having a branched structure and a repeating unit derived from a polyhydric alcohol having a branched structure. The polyester resin described in. The method for producing a polyester resin according to claim 1 or 2, wherein the polyvalent carboxylic acid and the polyhydric alcohol are polymerized in the presence of an antioxidant and a catalyst, wherein the catalyst is a titanium of Group 4A of the periodic table. Compound X containing at least one selected from the group consisting of group elements, compound Y containing at least one selected from the group consisting of groups 1A and 2A of the periodic table, manganese, iron, and cobalt, and a phosphorus compound. A method for producing a polyester resin which is a catalyst containing Z. The method for producing a polyester resin according to claim 3, wherein the polyvalent carboxylic acid or the polyhydric alcohol has a branched structure. The method for producing a polyester resin according to claim 4, wherein the polyvalent carboxylic acid or the polyvalent alcohol is contained in an amount of 0.1 to 30 mol parts based on 100 mol parts of the polyvalent carboxylic acid. A method for producing a polyester resin, wherein the polyester resin according to claim 1 or 2 is crosslinked with a polyester resin having a softening temperature of 80 ° C. or higher and 130 ° C. or lower with a radical reaction initiator.