JP5101180B2 - toner - Google Patents

Description

  The present invention relates to a toner used for developing a latent image formed in an electrophotographic method, an electrostatic recording method, an electrostatic printing method or the like.

  With the development of electrophotographic technology, a toner having excellent low-temperature fixability and storage stability is required. Therefore, a toner comprising a polyester having a softening point of 80 to 120 ° C. obtained by condensation polymerization of an alcohol component containing 1,2-propanediol and a carboxylic acid containing purified rosin and a release agent is disclosed. (See Patent Document 1).

  On the other hand, as the speed increases, there is a need for a toner having a property that is contrary to low-temperature fixability, such as offset resistance. Therefore, a toner containing a polyester having a softening point of 120 to 165 ° C. obtained by condensation polymerization of an alcohol component containing 1,2-propanediol and a carboxylic acid containing purified rosin is disclosed (Patent Document). 2).

Furthermore, from the viewpoint of grindability, a method of blending two types of polyesters having different softening points using aliphatic alcohol as the main raw material for the alcohol component is disclosed (see Patent Document 3).
Japanese Patent Laid-Open No. 2007-139813 JP 2007-137911 A JP 2002-287427 A

  However, with increasing machine speed, energy saving, and diversification of printing environment conditions, it has been found that conventional toner is insufficient for market demand. That is, the aliphatic alcohols used in Patent Documents 1, 2, and 3 have a high water absorption and insufficient storage stability at high temperatures and high humidity because of the large number of ester bonds in the molecule.

  Further, the purified rosin used in Patent Documents 1 and 2 has a limit in improving the storage stability because rosin is a monovalent acid and the amount of the rosin skeleton incorporated into the polyester molecule is limited. Furthermore, since rosin is a monovalent acid, when the polyester molecule is extended to the main chain, it is also preserved that this monocarboxylic acid, which is a purified rosin, cannot be extended and many low molecular weight products are produced. This is thought to be one of the reasons for the lack of sex.

  On the other hand, even when blending two types of polyesters with different softening points using aliphatic alcohol as the main ingredient of the alcohol component, all of low-temperature fixability, offset resistance and grindability in high-speed printing are maintained while maintaining grindability. It is difficult to prepare.

  An object of the present invention is to provide a toner that is excellent in all of low-temperature fixability, offset resistance, grindability, dispersibility of internal additives, and storage stability.

  As a result of repeated investigations to solve the above problems, the present inventors have made a condensation polymerization of an alcohol component containing 1,2-propanediol and a carboxylic acid component containing (meth) acrylic acid-modified rosin. A polyester resin obtained by polycondensation of 1,2-propanediol and an alcohol component containing 1,3-propanediol and a carboxylic acid component containing purified rosin. Thus, a toner excellent in all of low-temperature fixability, offset resistance, grindability, dispersibility of the internal additive and storage stability has been found, and the present invention has been completed.

  That is, the present invention is a toner comprising a polyester resin (A) and a polyester resin (B) having a softening point higher than that of the polyester resin (A) by 10 ° C. or more as a binder resin, The polyester resin (A) is obtained by polycondensing an alcohol component containing 65 mol% or more of 1,2-propanediol in a divalent alcohol component and a carboxylic acid component containing (meth) acrylic acid-modified rosin. A resin having a polyester unit, wherein the polyester resin (B) contains 1,2-propanediol and 1,3-propanediol in a divalent alcohol component in an amount of 70 mol% or more. And a toner which is a resin having a polyester unit obtained by condensation polymerization of a carboxylic acid component containing purified rosin.

  The toner of the present invention exhibits excellent effects such as excellent low-temperature fixability, offset resistance, grindability, dispersibility of the internal additive, and storage stability.

  The present invention provides a toner containing a polyester resin (A) and a polyester resin (B) having a softening point higher than that of the polyester resin (A) by 10 ° C. or more as a binder resin, the polyester resin ( A) is a polyester unit obtained by condensation polymerization of an alcohol component containing 65 mol% or more of 1,2-propanediol in a divalent alcohol component and a carboxylic acid component containing (meth) acrylic acid-modified rosin. A resin derived from a (meth) acrylic acid-modified rosin having a polyester resin (B) of 70 mol% or more of 1,2-propanediol and 1,3-propanediol combined in a divalent alcohol component It is a polyester which is a resin derived from a purified rosin having a polyester unit obtained by condensation polymerization of an alcohol component contained therein and a carboxylic acid component containing a purified rosin. In particular, it has a great feature.

  Since the (meth) acrylic acid-modified rosin used in the polyester resin (A) in the present invention is a rosin having two functional groups, the molecular chain can be extended as part of the main chain of the polyester to increase the molecular weight. On the other hand, low molecular weight components having a molecular weight of 500 or less, that is, residual monomer components and oligomer components are reduced. Furthermore, the alcohol component mainly composed of 1,2-propanediol is molecularly compact and highly reactive, so even if a (meth) acrylic acid-modified rosin having a high molecular weight and low reactivity is used. A polyester having a large number average molecular weight is obtained.

In addition, since a purified rosin having excellent storage stability is used in the polyester resin (B) in the present invention, and branched and linear propanediols are used in combination as alcohol components, Since the transition point is maintained and flexibility is imparted to the molecular chain by the linear 1,3-propanediol, the low temperature fixability can be maintained while maintaining the storage stability and the offset resistance. Acrylic acid-modified rosin has two functional groups, so when used in polyester with a high softening point, the molecular weight increases, so the storage stability and offset resistance are improved, but the reaction proceeds and the low-temperature fixability may be impaired. is there. Therefore, in the present invention, from the viewpoint of fixability, a monovalent purified rosin is used to suppress the molecular weight of the high softening point polyester.

  With the above configuration, it is presumed that the surprising effects of excellent storage stability, grindability, and dispersibility of the internal additive can be achieved while satisfying the contradictory properties of offset resistance and low-temperature fixability.

  Hereinafter, the raw material monomer of the polyester resin (A) will be described.

  The polyester resin (A) uses an alcohol component containing 65 mol% or more of 1,2-propanediol in a divalent alcohol component and a carboxylic acid component containing (meth) acrylic acid-modified rosin.

  1,2-propanediol, which is a branched-chain alcohol having 3 carbon atoms, used for the alcohol component of the polyester resin (A) in the present invention maintains offset resistance as compared with alcohol having 2 or less carbon atoms. It is effective for improving the low-temperature fixability as it is, and is effective for preventing a decrease in storage stability associated with a decrease in glass transition point as compared with a branched chain alcohol having 4 or more carbon atoms. Fixing at an extremely low temperature is possible, and a surprising effect is achieved that storage stability is improved while maintaining grindability.

  The alcohol component may contain an alcohol other than 1,2-propanediol as long as the effects of the present invention are not impaired. The content of 1,2-propanediol is a divalent alcohol component. Among them, it is 65 mol% or more, preferably 70 mol% or more, more preferably 80 mol% or more, further preferably 90 mol% or more, and further preferably substantially 100 mol%. Divalent alcohol components other than 1,2-propanediol include 1,3-propanediol, ethylene glycol having different carbon numbers, hydrogenated bisphenol A, or alkylene (2 to 4 carbon atoms) oxide (average addition) 1-16 moles) aliphatic dialcohols such as adducts, polyoxypropylene-2,2-bis (4-hydroxyphenyl) propane, polyoxyethylene-2,2-bis (4-hydroxyphenyl) propane, etc. Although an aromatic alcohol such as an alkylene oxide adduct of bisphenol A may be contained, it is preferable that the alcohol component of the polyester resin (A) consists essentially of an aliphatic alcohol. In the present specification, the “alcohol component consisting essentially of an aliphatic alcohol” means that the content of the aliphatic alcohol in the alcohol component is preferably 90 mol% or more, more preferably 95 mol% or more, even more preferably. Means 98 mol% or more, more preferably 99 mol% or more.

  On the other hand, the carboxylic acid component contains (meth) acrylic acid-modified rosin. The (meth) acrylic acid-modified rosin in the present invention is a rosin modified with (meth) acrylic acid, and is abietic acid, neoabietic acid, parastrinic acid, pimaric acid, isopimaric acid, sandaracopimaric acid, dehydroabietic acid And rosin containing repopimaric acid as a main component and obtained by addition reaction of (meth) acrylic acid. Specifically, among the main components of rosin, repopimaric acid having a conjugated double bond, abietic acid It can be obtained through a Diels-Alder reaction under heating with neoabietic acid and parastrinic acid and (meth) acrylic acid.

  In the present specification, “(meth) acryl” means acryl or methacryl. Therefore, (meth) acrylic acid means acrylic acid or methacrylic acid, and “(meth) acrylic acid-modified rosin” means rosin modified with acrylic acid or rosin modified with methacrylic acid. The (meth) acrylic acid-modified rosin in the present invention is preferably an acrylic acid-modified rosin modified with acrylic acid having little steric hindrance from the viewpoint of reaction activity in the Diels-Alder reaction.

  The degree of modification of rosin with (meth) acrylic acid ([meth) acrylic acid modification degree] is preferably 5 to 105, more preferably 20 to 105, from the viewpoint of increasing the molecular weight of the polyester and reducing the low molecular weight oligomer component. 40 to 105 are more preferable, and 60 to 105 are more preferable.

  The degree of (meth) acrylic acid modification is expressed by the formula (I):

(In the formula, X ₁ is the SP value of (meth) acrylic acid-modified rosin for calculating the degree of modification, and X ₂ is (meth) acrylic acid-modified obtained by reacting 1 mol of (meth) acrylic acid with 1 mol of rosin. (Saturated SP value of rosin, Y indicates SP value of rosin)
Is calculated by Here, the SP value means a softening point measured by a ring and ball automatic softening point tester described later. The saturated SP value means the SP value when the reaction of (meth) acrylic acid and rosin is caused to react until the SP value of the obtained (meth) acrylic acid-modified rosin reaches a saturation value. The molecule of formula (I) means the degree of increase in SP of rosin modified with (meth) acrylic acid, and the higher the value of formula (I), the higher the degree of modification.

  The production method of (meth) acrylic acid-modified rosin is not particularly limited. For example, rosin and (meth) acrylic acid are mixed and heated to about 180 to 260 ° C., and are contained in the rosin by Diels-Alder reaction. A (meth) acrylic acid-modified rosin can be obtained by adding (meth) acrylic acid to an acid having a conjugated double bond. The (meth) acrylic acid-modified rosin may be used as it is, or may be used after purification through an operation such as distillation.

  The rosin used in the (meth) acrylic acid-modified rosin in the present invention is natural rosin obtained from pine, isomerized rosin, dimerized rosin, polymerized rosin, disproportionated rosin, and the like, abietic acid, neoabietic acid, Any known rosin can be used without particular limitation as long as it is a rosin mainly composed of parastrinic acid, pimaric acid, isopimaric acid, sandaracopimaric acid, dehydroabietic acid and lepopimaric acid, but from the viewpoint of color, natural rosin pulp Natural rosin such as tall rosin obtained from tall oil obtained as a by-product in the step of producing rosin, gum rosin obtained from raw pine sprout, wood rosin obtained from pine stumps is preferred, and tall rosin is more preferred from the viewpoint of low-temperature fixability.

  The (meth) acrylic acid-modified rosin in the present invention is obtained through a Diels-Alder reaction under heating, so that impurities that cause odor are reduced and the odor is low, but the odor is further reduced. From the viewpoint of improving storage stability, (meth) acrylic acid-modified rosin is preferably obtained by modifying purified rosin with (meth) acrylic acid, and is obtained by modifying purified tall rosin with (meth) acrylic acid. More preferred.

  The purified rosin in the present invention is a rosin whose impurities are reduced by the purification process. By purifying rosin, impurities contained in rosin are removed. Main impurities include 2-methylpropane, acetaldehyde, 3-methyl-2-butanone, 2-methylpropanoic acid, butanoic acid, pentanoic acid, n-hexanal, octane, hexanoic acid, benzaldehyde, 2-pentylfuran, 2 , 6-dimethylcyclohexanone, 1-methyl-2- (1-methylethyl) benzene, 3,5-dimethyl-2-cyclohexene, 4- (1-methylethyl) benzaldehyde and the like. In the present invention, among these, the peak intensity of three types of impurities, hexanoic acid, pentanoic acid, and benzaldehyde, detected as a volatile component by the headspace GC-MS method, can be used as an indicator of purified rosin. The reason why the volatile component rather than the absolute amount of impurities is used as an indicator is that the use of the purified rosin in the present invention can improve the odor over the conventional polyester using the rosin.

That is, the purified rosin in the present invention has a hexanoic acid peak intensity of 0.8 × 10 ⁷ or less and a pentanoic acid peak intensity of 0.4 × 10 ⁷ or less under the measurement conditions of the headspace GC-MS method described later. Rosin having a peak intensity of benzaldehyde of 0.4 × 10 ⁷ or less. Furthermore, from the viewpoint of storage stability and odor, the peak intensity of hexanoic acid is preferably 0.6 × 10 ⁷ or less, and more preferably 0.5 × 10 ⁷ or less. The peak intensity of pentanoic acid is preferably 0.3 × 10 ⁷ or less, and more preferably 0.2 × 10 ⁷ or less. The peak intensity of benzaldehyde is preferably 0.3 × 10 ⁷ or less, and more preferably 0.2 × 10 ⁷ or less.

Furthermore, from the viewpoint of storage stability and odor, it is preferable that n-hexanal and 2-pentylfuran are reduced in addition to the above three substances. The peak intensity of n-hexanal is preferably 1.7 × 10 ⁷ or less, more preferably 1.6 × 10 ⁷ or less, and further preferably 1.5 × 10 ⁷ or less. The peak intensity of 2-pentylfuran is preferably 1.0 × 10 ⁷ or less, more preferably 0.9 × 10 ⁷ or less, and further preferably 0.8 × 10 ⁷ or less.

  As a purification method of rosin, known methods can be used, and methods such as distillation, recrystallization, extraction and the like can be mentioned, and purification by distillation is preferable. As the distillation method, for example, the method described in JP-A-7-286139 can be used, and examples thereof include vacuum distillation, molecular distillation, steam distillation, etc., but purification by vacuum distillation is preferable. For example, distillation is usually performed at a still temperature of 200 to 300 ° C. at a pressure of 6.67 kPa or less, and methods such as ordinary simple distillation, thin film distillation, rectification, etc. are applied. On the other hand, 2 to 10% by weight of a high molecular weight substance is removed as a pitch component, and at the same time, 2 to 10% by weight of an initial fraction is simultaneously removed.

  The softening point of the rosin before modification is preferably 50 to 100 ° C, more preferably 60 to 90 ° C, and further preferably 65 to 85 ° C. The softening point of rosin in the present invention means a softening point measured when the rosin is once melted by the method described later and naturally cooled for 1 hour in an environment of a temperature of 25 ° C. and a relative humidity of 50%. .

  Furthermore, the acid value of rosin before modification is preferably 100 to 200 mgKOH / g, more preferably 130 to 180 mgKOH / g, and further preferably 150 to 170 mgKOH / g.

  The content of the (meth) acrylic acid-modified rosin is preferably 5% by weight or more and more preferably 10% by weight or more from the viewpoint of low-temperature fixability in the carboxylic acid component. Further, from the viewpoint of storage stability, it is preferably 85% by weight or less, more preferably 65% by weight or less, and further preferably 50% by weight or less. From these viewpoints, the content of the (meth) acrylic acid-modified rosin is preferably 5 to 85% by weight, more preferably 5 to 65% by weight, and further preferably 10 to 50% by weight in the carboxylic acid component.

  As carboxylic acid compounds other than (meth) acrylic acid-modified rosin contained in the carboxylic acid component, oxalic acid, malonic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, succinic acid, adipic acid, Aliphatic dicarboxylic acids such as sebacic acid, azelaic acid, n-dodecyl succinic acid, n-dodecenyl succinic acid; aromatic dicarboxylic acids such as phthalic acid, isophthalic acid, terephthalic acid; alicyclic dicarboxylic acids such as cyclohexane dicarboxylic acid; and These acid anhydrides, alkyl (C1-3) esters and the like can be mentioned. Such acids, anhydrides of these acids, and alkyl esters of these acids are collectively referred to herein as carboxylic acid compounds. Among the above, aromatic dicarboxylic acids such as phthalic acid, isophthalic acid and terephthalic acid are preferable from the viewpoint of durability.

  Next, the raw material monomer of the polyester resin (B) will be described.

  The polyester resin (B) comprises 1,2-propanediol and 1,3-propanediol in a divalent alcohol component and an alcohol component containing 70 mol% or more, and a carboxylic acid component containing purified rosin. Use.

  The 1,2-propanediol having 3 carbon atoms used for the alcohol component of the polyester resin (B) in the present invention is effective in improving low-temperature fixability as compared with an alcohol having 2 or less carbon atoms. Compared with the above alcohols, it is effective in preventing deterioration in storage stability accompanying a decrease in glass transition point. Furthermore, in the polyester resin (B) in the present invention, since 1,2-propanediol is used in combination with linear 1,3-propanediol, the glass transition point of the polyester can be kept high. . In addition, the linear 1,3-propanediol imparts flexibility to the molecular chain, so that low temperature fixability can be ensured while maintaining offset resistance in oilless fixing.

  In the alcohol component of the polyester resin (B), the molar ratio of 1,2-propanediol to 1,3-propanediol (1,2-propanediol / 1,3-propanediol) is low temperature fixability and storage stability. From the viewpoint of achieving both, 70/30 to 99/1, preferably 75/25 to 95/5, and more preferably 77/23 to 85/15.

  The alcohol component may contain alcohol other than 1,2-propanediol and 1,3-propanediol as long as the effects of the present invention are not impaired. The total content of 3-propanediol is preferably 70 to 100 mol%, more preferably 80 to 100 mol%, and still more preferably 90 to 100 mol% in the divalent alcohol component. Examples of 1,2-propanediol and divalent alcohol components other than 1,3-propanediol include alkylene oxide adducts of bisphenol A, ethylene glycol, hydrogenated bisphenol A, sorbitol, or alkylenes thereof (2 to 4) Oxide (average added mole number: 1 to 16) adduct and the like. The content of the divalent alcohol component is preferably 70 to 100 mol%, more preferably 80 to 100 mol%, still more preferably 90 to 100 mol%, still more preferably 100 mol% in the alcohol component.

  On the other hand, the carboxylic acid component contains purified rosin. As the purified rosin, those described in the section of the polyester resin (A) can be used.

  The content of the purified rosin is preferably 2 to 50% by weight, more preferably 5 to 45% by weight, and further preferably 10 to 40% by weight in the carboxylic acid component from the viewpoint of storage stability.

  The carboxylic acid component other than the purified rosin preferably contains an aliphatic dicarboxylic acid compound having 2 to 4 carbon atoms. Examples of the aliphatic dicarboxylic acid compound having 2 to 4 carbon atoms include adipic acid, maleic acid, malic acid, succinic acid, fumaric acid, citraconic acid, itaconic acid, and anhydrides of these acids. Among these, it is more preferable that at least one aliphatic dicarboxylic acid compound selected from the group consisting of succinic acid, fumaric acid, citraconic acid, itaconic acid and anhydrides of these acids is contained. Since these aliphatic dicarboxylic acid compounds impart flexibility to the molecular chain, they are effective in improving low-temperature fixability. In the present invention, itaconic acid is preferable among the aliphatic dicarboxylic acid compounds.

  The content of the aliphatic dicarboxylic acid is preferably 0.5 to 20 mol% and more preferably 1 to 15 mol% in the carboxylic acid component from the viewpoint of improving the low-temperature fixability and suppressing the decrease in the glass transition point. Further, the carboxylic acid component may contain a carboxylic acid compound other than the aliphatic carboxylic acid compound and the purified rosin as long as the effects of the present invention are not impaired, and ensuring storage stability (that is, glass From the viewpoint of securing a transition point, it is preferable that an aromatic dicarboxylic acid such as phthalic acid, isophthalic acid, terephthalic acid or the like is contained. The content of the aromatic dicarboxylic acid is preferably 40 to 95 mol%, more preferably 50 to 95 mol%, still more preferably 60 to 80 mol% in the carboxylic acid component.

  In the polyester-based resin (A) and the polyester-based resin (B) in the present invention, the alcohol component is a trihydric or higher polyhydric alcohol and / or the carboxylic acid component is a trivalent or higher from the viewpoint of improving offset resistance. It preferably contains a polyvalent carboxylic acid compound. Examples of the trihydric or higher polyhydric alcohol include glycerin, pentaerythritol, trimethylolpropane, sorbitol, or an alkylene (carbon number 2 to 4) oxide (average added mole number 1 to 16) adduct thereof. Examples of the polyvalent carboxylic acid compound having a valence or higher include trimellitic acid, pyromellitic acid, anhydrides of these acids, and alkyl (C1-3) esters. Among these, trimellitic acid and its derivatives (anhydrides and alkyl (C1-3) esters) are preferable. In the polyester resin (A), not only becomes a branching site or acts as a crosslinking agent but also at a low temperature. Trimellitic acid and its derivatives are preferable because they are also effective for improving the fixing property.

  The content of trivalent or higher raw material monomers (trivalent or higher polyhydric alcohol and trivalent or higher polyvalent carboxylic acid compound) is preferably 1 to 25 mol%, and 3 to 23 mol in all raw material monomers in each resin. % Is more preferable, and 7 to 21 mol% is more preferable.

  Further, from the viewpoint of achieving both offset resistance and storage stability, it is more preferable for the polyester-based resin (A) that the trivalent or higher raw material monomer is contained only in the carboxylic acid component. Since the (meth) acrylic acid-modified rosin used in the present invention is a rosin having two functional groups, trivalent or higher raw material monomers can be used without impairing the low-temperature fixability of the rosin. The offset resistance can be further improved while maintaining the properties. From these viewpoints, the content of the trivalent or higher polyvalent carboxylic acid compound of the polyester-based resin (A) is preferably 0.001 to 40 mol with respect to 100 mol of the alcohol component of the polyester-based resin (A). 25 mol is more preferable, and the content of the trihydric or higher polyhydric alcohol in the polyester resin (A) is preferably 0.001 to 40 mol%, and 0.1 to 25 mol% in the alcohol component of the polyester resin (A). More preferred.

  The polycondensation of the alcohol component and the carboxylic acid component of the polyester resin (A) and the polyester resin (B) in the present invention is preferably performed in the presence of an esterification catalyst. Preferable examples of the esterification catalyst in the present invention include a titanium compound and a tin (II) compound having no Sn—C bond, and these are used alone or in combination.

  As a titanium compound, the titanium compound which has a Ti-O bond is preferable, and the compound which has a C1-28 total carbon number alkoxy group, an alkenyloxy group, or an acyloxy group is more preferable.

Specific examples of the titanium compound include titanium diisopropylate bistriethanolaminate [Ti (C ₆ H ₁₄ O ₃ N) ₂ (C ₃ H ₇ O) ₂ ], titanium diisopropylate bisdiethanolamate [Ti (C ₄ H ₁₀ O ₂ N) ₂ (C ₃ H ₇ O) ₂ ], titanium dipentylate bistriethanolaminate [Ti (C ₆ H ₁₄ O ₃ N) ₂ (C ₅ H ₁₁ O) ₂ ], titanium diethyl Rate bistriethanolaminate [Ti (C ₆ H ₁₄ O ₃ N) ₂ (C ₂ H ₅ O) ₂ ], titanium dihydroxyoctylate bistriethanolaminate [Ti (C ₆ H ₁₄ O ₃ N) ₂ (OHC ₈ H ₁₆ O) ₂ ], titanium distearate bistriethanolamate [Ti (C ₆ H ₁₄ O ₃ N) ₂ (C ₁₈ H ₃₇ O) ₂ ], titanium triisopropylate triethanolamate [Ti (C _{6 H 14 O 3 N) (C} 3 H 7 O) 3 ], titanium monopropylate tris (triethanolaminate) _{[Ti (C 6 H 14 O 3} N) 3 (C 3 H 7 O) Among these, titanium diisopropylate bistriethanolamate, titanium diisopropylate bisdiethanolamate, and titanium dipentylate bistriethanolamate are preferred, and these are, for example, commercial products of Matsumoto Trading Co., Ltd. Is also available.

Specific examples of other preferable titanium compounds include tetra-n-butyl titanate [Ti (C ₄ H ₉ O) ₄ ], tetrapropyl titanate [Ti (C ₃ H ₇ O) ₄ ], tetrastearyl titanate [Ti ( C ₁₈ H ₃₇ O) ₄ ], tetramyristyl titanate [Ti (C ₁₄ H ₂₉ O) ₄ ], tetraoctyl titanate [Ti (C ₈ H ₁₇ O) ₄ ], dioctyl dihydroxyoctyl titanate [Ti (C ₈ H ₁₇ O) ₂ (OHC ₈ H ₁₆ O) ₂ ], dimyristyl dioctyl titanate [Ti (C ₁₄ H ₂₉ O) ₂ (C ₈ H ₁₇ O) ₂ ] and the like. Among these, tetrastearyl titanate, tetra Myristyl titanate, tetraoctyl titanate and dioctyl dihydroxy octyl titanate are preferred, which can be obtained, for example, by reacting a titanium halide with the corresponding alcohol, but also as a commercial product such as Nisso Corporation It is available.

  The amount of the titanium compound present is preferably 0.01 to 1.0 part by weight and more preferably 0.1 to 0.7 part by weight with respect to 100 parts by weight of the total amount of the alcohol component and the carboxylic acid component.

  Examples of the tin (II) compound having no Sn—C bond include a tin (II) compound having a Sn—O bond, a tin (II) compound having a Sn—X (X represents a halogen atom) bond, and the like. Preferably, a tin (II) compound having a Sn—O bond is more preferable.

Examples of tin (II) compounds having Sn-O bonds include tin (II) oxalate, tin (II) acetate, tin (II) octoate, tin (II) 2-ethylhexanoate, and tin (II) laurate. , Tin (II) carboxylate having a carboxylic acid group having 2 to 28 carbon atoms such as tin (II) stearate, tin (II) oleate; octyloxy tin (II), lauroxy tin (II), stearoxy tin (II) ), Alkoxytin (II) having an alkoxy group having 2 to 28 carbon atoms such as oleyloxytin (II); tin (II) oxide; tin (II) sulfate, Sn—X (X represents a halogen atom) Examples of the tin (II) compound having a bond include tin (II) halides such as tin (II) chloride and tin (II) bromide, and among these, from the standpoint of charge rising effect and catalytic ability , (R ¹ COO) ₂ Sn (wherein R ¹ represents an alkyl group or alkenyl group having 5 to 19 carbon atoms), (R ² O) ₂ Sn (where R ² Is C 6-20 alk An alkoxytin (II) represented by SnO or a tin (II) oxide represented by SnO, and a fatty acid tin (II) and tin oxide represented by (R ¹ COO) ₂ Sn (II) is more preferred, and tin (II) octoate, tin (II) 2-ethylhexanoate, tin (II) stearate and tin (II) oxide are more preferred.

  The abundance of the tin (II) compound is preferably 0.01 to 1.0 part by weight, more preferably 0.1 to 0.7 part by weight, based on 100 parts by weight of the total amount of the alcohol component and the carboxylic acid component.

  When the titanium compound and the tin (II) compound are used in combination, the total amount of the titanium compound and the tin (II) compound is preferably 0.01 to 1.0 part by weight with respect to 100 parts by weight of the total amount of the alcohol component and the carboxylic acid component, 0.1-0.7 weight part is more preferable.

  The polycondensation of the alcohol component and the carboxylic acid component can be performed, for example, at a temperature of 180 to 250 ° C. in an inert gas atmosphere in the presence of the esterification catalyst.

  The difference in softening point between the two types of polyester resins is 10 ° C. or more from the viewpoint of enhancing the dispersibility of the internal additive and enhancing the effect on fixing property and offset resistance, particularly high-temperature offset resistance. In achromatic toners such as black toner, the temperature is preferably 10 to 60 ° C., more preferably 20 to 50 ° C., from the viewpoint of suppressing gloss. In addition, in chromatic color toners such as yellow toner, magenta toner, and cyan toner, 10 to 30 ° C. is preferable and 15 to 30 ° C. is more preferable from the viewpoint of improving gloss. The softening point of the polyester resin (A) having a lower softening point is preferably from 80 to 120 ° C, more preferably from 90 to 110 ° C, from the viewpoint of fixability. On the other hand, the softening point of the polyester resin (B) having a higher softening point is preferably from 100 to 180 ° C, more preferably from 120 to 180 ° C, and even more preferably from 120 to 160 ° C, from the viewpoint of high temperature offset resistance.

  The glass transition point of the polyester resin (A) and the polyester resin (B) is preferably 45 to 75 ° C, and more preferably 50 to 70 ° C, from the viewpoints of fixability, storage stability and durability. From the viewpoint of chargeability and environmental stability, the acid value is preferably 1 to 80 mgKOH / g, more preferably 5 to 60 mgKOH / g, and even more preferably 5 to 50 mgKOH / g.

  In the present invention, the polyester units in the polyester resins (A) and (B) are preferably amorphous different from crystallinity. In this specification, an amorphous resin refers to a resin having a difference between the softening point and the glass transition point (Tg) of 30 ° C. or more.

  The weight ratio of the polyester-based resin (A) to the polyester-based resin (B) is preferably 10/90 to 90/10, more preferably 20/80 to 80/20, from the viewpoint of fixability and durability. 70 to 70/30 is more preferable.

  In the present invention, when the binder resin is composed of three or more polyester resins, the total content in the binder resin is 50% by weight or more, preferably 70% by weight or more, more preferably 80% by weight. Any two kinds of resins as described above may satisfy the relationship between the softening points of the polyester resin (A) and the polyester resin (B). Accordingly, the binder resin includes a polyester resin not including polyester resin (A) and polyester resin (B) as other binder resins within a range not impairing the effects of the present invention. Other resin such as vinyl resin such as styrene-acrylic resin, epoxy resin, polycarbonate, polyurethane may be used in combination. The content of the other binder resin is preferably 1 to 30% by weight and more preferably 1 to 20% by weight in the binder resin.

  In the present invention, the polyester resin means a resin having a polyester unit. The polyester unit refers to a portion having a polyester structure, and the polyester resin includes not only polyester but also polyester modified to such an extent that the properties are not substantially impaired. Both (A) and (B) are preferably polyesters. Examples of the modified polyester include grafting and blocking with phenol, urethane, epoxy and the like by the methods described in JP-A-11-133668, JP-A-10-239903, JP-A-8-20636, and the like. And a composite resin having two or more types of resin units including a polyester unit.

  As the other binder resin, a composite resin having a condensation polymerization resin unit and an addition polymerization resin unit is preferable from the viewpoint of dispersibility of wax, and addition polymerization of a condensation polymerization resin unit such as polyester and a vinyl resin is preferable. A composite resin having a resin-based resin unit is more preferable. The ratio of the total weight of the polyester resins (A) and (B) to the weight of the composite resin (polyester resin (A) + (B) / composite resin) is 80/20 to 97/3. Is more preferable, and 85/15 to 95/5 is more preferable.

  As a raw material monomer of the polyester unit in the composite resin, an alcohol component obtained by removing 1,2-propanediol and 1,3-propanediol from the alcohol components of the polyester resins (A) and (B) and the polyester resin (A ) And (B) carboxylic acid components excluding (meth) acrylic acid-modified rosin and purified rosin.

  On the other hand, the raw material monomer of the vinyl resin unit includes styrene compounds such as styrene and α-methylstyrene; ethylenically unsaturated monoolefins such as ethylene and propylene; diolefins such as butadiene; halovinyls such as vinyl chloride; Vinyl esters such as vinyl and vinyl propionate; alkyl (1 to 18 carbon atoms) esters of (meth) acrylic acid, esters of ethylenic monocarboxylic acids such as dimethylaminoethyl (meth) acrylate; vinyl methyl ether, etc. Vinyl ethers; vinylidene halides such as vinylidene chloride; N-vinyl compounds such as N-vinylpyrrolidone, and the like. Among these, styrene, 2-ethylhexyl acrylate, butyl acrylate and acrylic acid long-chain alkyl (carbon (Equation 12-18) ester is preferred and charged From the viewpoint, styrene, from the viewpoint of fixability and adjustment of the glass transition point, alkyl esters of (meth) acrylic acid are preferred. The content of styrene is preferably 50 to 90% by weight and more preferably 75 to 85% by weight in the raw material monomer of the vinyl resin. The monomer weight ratio of styrene to the alkyl ester of (meth) acrylic acid (styrene / alkyl ester of (meth) acrylic acid) is preferably 50/50 to 95/5, more preferably 70/30 to 95/5.

  In addition, you may use a polymerization initiator, a crosslinking agent, etc. for the addition polymerization of the raw material monomer of a vinyl-type resin unit as needed.

  In the present invention, the weight ratio of the raw material monomer of the polyester unit to the raw material monomer of the addition polymerization resin unit (raw material monomer of the polyester unit / raw material monomer of the addition polymerization resin unit) is such that the continuous phase is the polyester unit and the dispersed phase Is preferably an addition polymerization type resin unit, 50/50 to 95/5 is preferable, and 60/40 to 95/5 is more preferable.

  In the present invention, the composite resin is a compound capable of reacting with both the raw material monomer of the polyester unit and the raw material monomer of the addition polymerization resin unit, as well as the raw material monomer of the polyester unit and the addition polymerization resin unit (both A resin (hybrid resin) obtained using a reactive monomer) is preferable.

  As the both reactive monomers, at least one functional group selected from the group consisting of a hydroxyl group, a carboxyl group, an epoxy group, a primary amino group and a secondary amino group in the molecule, and an ethylenically unsaturated bond A compound having the above formula is preferred, and by using such a bireactive monomer, the dispersibility of the resin to be the dispersed phase can be further improved. Specific examples of the both reactive monomers include, for example, acrylic acid, fumaric acid, methacrylic acid, citraconic acid, maleic acid, 2-hydroxyethyl (meth) acrylate, glycidyl (meth) acrylate, and carboxylic acids thereof. Derivatives such as anhydrides and alkyl (1 to 2 carbon atoms) esters may be mentioned, and among these, acrylic acid, methacrylic acid, fumaric acid, maleic acid and derivatives of these carboxylic acids are preferred from the viewpoint of reactivity.

  In the present invention, among the two reactive monomers, a monomer having two or more functional groups (polycarboxylic acid or the like) and a derivative thereof are used as a raw material monomer for the polyester unit as a monomer having one functional group (monocarboxylic acid or the like) and The derivative is treated as a raw material monomer for the addition polymerization resin unit. The amount of the both reactive monomers used is preferably 1 to 30 moles with respect to 100 moles of the raw material monomer of the polyester unit excluding the both reactive monomers, and from the viewpoint of further enhancing the dispersibility of the addition polymerization resin unit. In the process of producing the resin, in the method of reacting at a high temperature after the addition polymerization reaction, 1.5 to 20 mol is more preferable, and 2 to 10 mol is more preferable. After the addition polymerization reaction, the both reactivity is maintained while keeping the reaction temperature constant. In the method using a large amount of monomer, 4 to 15 mol is more preferable, and 4 to 10 mol is more preferable.

  In the present invention, from the viewpoint of uniformity of the polyester unit and the addition polymerization resin unit, the composite resin is prepared by previously mixing the raw material monomer of the polyester unit and the raw material monomer of the addition polymerization resin unit, and performing the condensation polymerization reaction and the addition polymerization reaction. Is preferably a resin obtained by performing in parallel in the same reaction vessel, and when the composite resin is a hybrid resin obtained by using both reactive monomers, the raw material monomer of the condensation polymerization resin unit In addition, it is preferable to use a resin obtained by previously mixing a mixture of monomers as raw materials for the addition polymerization resin unit and the both reactive monomers and performing the condensation polymerization reaction and the addition polymerization reaction in parallel in the same reaction vessel.

  In the present invention, the progress and completion of the condensation polymerization reaction and the addition polymerization reaction do not need to be simultaneous in time, and the reaction temperature and time are appropriately selected according to each reaction mechanism to allow the reaction to proceed and complete. Just do it. For example, the raw material monomer of the polyester unit, the raw material monomer of the addition polymerization resin unit, the bireactive monomer, etc. are mixed, and first, polycondensation is carried out by the addition polymerization reaction mainly at temperature conditions suitable for the addition polymerization reaction, for example, 50 to 180 ° C. After forming an addition polymerization resin having a functional group capable of reaction, the reaction temperature is then raised to a temperature condition suitable for the condensation polymerization reaction, for example, 190 to 270 ° C. The method of forming resin is mentioned.

  The toner of the present invention further includes a colorant, a release agent, a charge control agent, a magnetic powder, a fluidity improver, a conductivity modifier, an extender pigment, a reinforcing filler such as a fibrous substance, an antioxidant, and an aging agent. Additives such as an inhibitor and a cleaning property improver may be appropriately contained.

  As the colorant, all of dyes and pigments used as toner colorants can be used, and carbon black; I. C.I. Pigment Yellow 1, 3, 74, 97, 98, etc. acetoacetic acid arylamide monoazo yellow pigments; I. C.I. Pigment Yellow 12, 13, 14, 17, etc. acetoacetic acid arylamide disazo yellow pigments; I. Pigment Yellow 93, 95, and other polyazo yellow pigments; C.I. I. Pigment yellow 180; C.I. I. Pigment yellow 185; C.I. I. Solvent Yellow 19, 77, 79, C.I. I. Yellow dyes such as disperse yellow 164; I. CI Pigment Red 48, 49: 1, 53: 1, 57, 57: 1, 81, 122, 184, 5 and the like; I. Red dyes such as Solvent Red 49, 52, 58, 8; I. Blue dyes and pigments of copper phthalocyanine and its derivatives such as CI Pigment Blue 15: 3; I. Pigment Green 7 and 36 (phthalocyanine green) and the like, and these may be used alone or in combination of two or more. Either color toner or full color toner may be used. The content of the colorant is preferably 1 to 15 parts by weight with respect to 100 parts by weight of the total amount of the vinyl resin and polyester in the dispersion.

  As release agents, low molecular weight polyolefins such as polyethylene, polypropylene and polybutene; silicones; fatty acid amides such as oleic acid amide, erucic acid amide, ricinoleic acid amide and stearic acid amide; carnauba wax, rice wax, candelilla Plant waxes such as wax, tree wax and jojoba oil; animal waxes such as beeswax; mineral and petroleum waxes such as montan wax, ozokerite, ceresin, paraffin lux, microcrystalline wax, and Fischer-Tropsch wax. These release agents may be used alone or in combination of two or more.

  The melting point of the release agent is preferably from 50 to 120 ° C., more preferably below the softening point of the binder resin, in consideration of the blocking resistance and the influence on the low-temperature fixability of the binder resin. The content of the release agent is preferably 1 to 20 parts by weight, more preferably 2 to 15 parts per 100 parts by weight of the binder resin in consideration of the effect on the low temperature offset and the influence on the chargeability. Part by weight, more preferably 2 to 10 parts by weight.

  As the charge control agent, any one of negative chargeability and positive chargeability can be used. Examples of the negatively chargeable charge control agent include metal-containing azo dyes, copper phthalocyanine dyes, metal complexes of salicylic acid alkyl derivatives, and nitroimidazole derivatives. Examples of the positively chargeable charge control agent include nigrosine dyes, triphenylmethane dyes, quaternary ammonium salt compounds, polyamine resins, and imidazole derivatives. Also, a polymer type such as a resin can be used. The content of the charge control agent is preferably 0.1 to 8 parts by weight and more preferably 0.2 to 5 parts by weight with respect to 100 parts by weight of the binder resin.

The electrophotographic toner of the present invention may be a toner obtained by any conventionally known method such as a melt-kneading method, an emulsion phase inversion method, or a polymerization method. From the viewpoint, a pulverized toner obtained by a melt-kneading method including a step of melt-kneading a binder resin, that is, at least two polyester resins having different softening points, is preferable. In the case of the pulverized toner by the melt-kneading method, specifically, the additives such as the binder resin, the colorant, and the release agent are mixed with a mixer such as a Henschel mixer, and then the sealed kneader, uniaxial or biaxial The toner can be produced by melt-kneading with an extruder, open roll type kneader, etc., cooling, pulverizing and classifying. The volume median particle diameter (D ₅₀ ) of the toner is preferably 3 to 15 μm, more preferably 4 to 10 μm. In the present specification, the volume-median particle size (D ₅₀ ) means a particle size at which the cumulative volume frequency calculated by the volume fraction is 50% when calculated from the smaller particle size.

  Further, the toner of the present invention may be externally treated with an external additive such as inorganic fine particles such as silica, alumina, titania, zirconia, tin oxide and zinc oxide, and organic fine particles such as resin fine particles. Good.

As the external additive, silica having a small specific gravity is preferable from the viewpoint of preventing embedding. From the viewpoint of environmental stability, the silica is preferably hydrophobic silica that has been subjected to a hydrophobic treatment. The method for hydrophobizing is not particularly limited, and examples of the hydrophobizing agent include hexamethyldisilazane (HMDS), dimethyldichlorosilane (DMDS), silicone oil, methyltriethoxysilane, and the like. The treatment amount of the hydrophobizing agent is preferably 1 to 7 mg / m ² per surface area of the inorganic fine particles.

  The number average particle diameter of the external additive is preferably from 3 to 300 nm, more preferably from 5 to 100 nm, from the viewpoint of chargeability and prevention of scratches on the photoreceptor.

  The content of the external additive is preferably 0.01 to 10 parts by weight and more preferably 0.1 to 5 parts by weight with respect to 100 parts by weight of the toner base particles.

  The toner of the present invention can be used as a one-component developing toner or as a two-component developer mixed with a carrier.

When used as a two-component developer, in the present invention, from the viewpoint of image characteristics, it is preferable to use a carrier with low saturation magnetization that weakens the area around the magnetic brush. Saturation magnetization of the carrier is preferably ^{40~100Am 2 / kg, 50~90Am 2 /} kg is more preferable. The saturation magnetization is preferably 100 Am ² / kg or less from the viewpoint of adjusting the hardness of the magnetic brush and maintaining gradation reproducibility, and preferably 40 Am ² / kg or more from the viewpoint of preventing carrier adhesion and toner scattering.

  As the core material of the carrier, those made of known materials can be used without particular limitation, for example, ferromagnetic metals such as iron, cobalt, nickel, magnetite, hematite, ferrite, copper-zinc-magnesium ferrite, Examples include alloys and compounds such as manganese ferrite and magnesium ferrite, and glass beads. Among these, iron powder, magnetite, ferrite, copper-zinc-magnesium ferrite, manganese ferrite, and magnesium ferrite are preferable from the viewpoint of chargeability. From the viewpoint of image quality, ferrite, copper-zinc-magnesium ferrite, manganese ferrite and magnesium ferrite are more preferable.

  The surface of the carrier is preferably coated with a resin from the viewpoint of reducing carrier contamination. The resin that coats the carrier surface varies depending on the toner material. For example, fluororesin such as polytetrafluoroethylene, monochlorotrifluoroethylene polymer, polyvinylidene fluoride, silicone resin such as polydimethylsiloxane, polyester, styrenic resin, Acrylic resins, polyamides, polyvinyl butyral, amino acrylate resins, and the like can be used, and these can be used alone or in combination of two or more. However, when the toner is negatively charged, the chargeability and surface From the viewpoint of energy, a silicone resin is preferable. The method for coating the core material with the resin is not particularly limited, for example, a method in which a coating material such as a resin is dissolved or suspended in a solvent and applied to the core material, or a method of simply mixing with a powder.

  In the two-component developer of the present invention obtained by mixing the toner and the carrier, the toner to carrier weight ratio (toner / carrier) is preferably 1/99 to 10/90, and 5/95 to 7/93. More preferred.

[Softening point of resin]
Using a flow tester (Shimadzu Corporation, CFT-500D), a 1 g sample is heated at a heating rate of 6 ° C / min. While applying a load of 1.96 MPa with a plunger and extruded from a nozzle with a diameter of 1 mm and a length of 1 mm. . The amount of plunger drop of the flow tester is plotted against the temperature, and the temperature at which half of the sample flows out is taken as the softening point.

[Softening point of rosin]
(1) Sample preparation 10g of rosin is melted on a hot plate at 170 ° C for 2 hours. Then, it is naturally cooled for 1 hour in an open state in an environment of a temperature of 25 ° C. and a relative humidity of 50%, and pulverized in a coffee mill (National MK-61M) for 10 seconds.
(2) Measurement Using a flow tester (Shimadzu Corporation, CFT-500D), a 1 g sample was heated at a heating rate of 6 ° C / min, and a load of 1.96 MPa was applied by a plunger, with a diameter of 1 mm and a length of 1 mm. Extrude from nozzle. The amount of plunger drop of the flow tester is plotted against the temperature, and the temperature at which half of the sample flows out is taken as the softening point.

[Glass transition point of resin and rosin]
Using a differential scanning calorimeter (Seiko Denshi Kogyo Co., Ltd., DSC210), weigh 0.01 to 0.02 g of the sample into an aluminum pan, raise the temperature to 200 ° C, and from that temperature to 0 ° C at a rate of 10 ° C / min. The temperature of the cooled sample is raised at a heating rate of 10 ° C / min, and the temperature at the intersection of the base line extension below the maximum peak temperature of endotherm and the tangent that indicates the maximum slope from the peak rise to the peak apex To do.

[Acid value of resin and rosin]
Measured according to the method of JIS K0070. However, only the measurement solvent was changed from the mixed solvent of ethanol and ether specified in JIS K0070 to the mixed solvent of acetone and toluene (acetone: toluene = 1: 1 (volume ratio)).

[SP value of rosin]
After pouring 2.1 g of the molten sample into a predetermined ring, the sample is cooled to room temperature and then measured under the following conditions based on JIS B7410.
Measuring machine: Ring-and-ball automatic softening point tester ASP-MGK2 (manufactured by Meitec)
Temperature increase rate: 5 ℃ / min
Temperature rise start temperature: 40 ℃
Measuring solvent: Glycerin

(Degree of (meth) acrylic acid modification of rosin)
Formula (I):

(In the formula, X ₁ is the SP value of (meth) acrylic acid-modified rosin for calculating the degree of modification, and X ₂ is (meth) acrylic acid-modified obtained by reacting 1 mol of (meth) acrylic acid with 1 mol of rosin. (Saturated SP value of rosin, Y indicates SP value of rosin)
Calculated by The saturated SP value means the SP value when the reaction of (meth) acrylic acid and rosin is allowed to react until the SP value of the obtained (meth) acrylic acid-modified rosin reaches a saturation value. The molecular weight of the rosin 1 mol, when the acid value x (mg KOH / g), potassium hydroxide relative to the rosin 1 g (molecular weight: 56.1) that is xmg (x × 10 ^-3 g) reaction Therefore, the formula (II):
Molecular weight = 56100 ÷ x (II)
Can be calculated.

[Melting point of release agent]
Using a differential scanning calorimeter (Seiko Denshi Kogyo Co., Ltd., DSC210), the temperature was raised to 200 ° C, and the sample was cooled to 0 ° C at a temperature drop rate of 10 ° C / min. The maximum peak temperature of heat of fusion is taken as the melting point.

[Number average particle diameter of external additives]
Obtained from the following formula.
Number average particle diameter (nm) = 6 / (ρ × specific surface area (m ² / g)) × 1000
In the formula, ρ is the specific gravity of the inorganic fine powder or the external additive, and the specific surface area is the original BET specific surface area obtained by the nitrogen adsorption method of the raw material, or in the case of the external additive, before the hydrophobic treatment. is there. For example, the specific gravity of silica is 2.2 and the specific gravity of titanium oxide is 4.2.
The above formula is assumed to be a sphere having a particle size R,
BET specific surface area = S x (1 / m)
m (weight of particle) = 4/3 x π x (R / 2) ³ x specific gravity
S (surface area) = 4π (R / 2) ²
Is an expression obtained from

[Volume-median particle size of toner (D ₅₀ )]
In this specification, the volume-median particle size (D ₅₀ ) of the toner means the particle size of the toner in which the cumulative volume frequency calculated by the volume fraction is 50% calculated from the smaller particle size.
Measuring instrument: "Coulter Multisizer II" (Beckman Coulter, Inc.)
Aperture diameter: 50μm
Analysis software: Coulter Multisizer AccuComp version 1.19 (Beckman Coulter)
Electrolyte: Isoton II (Beckman Coulter)
Dispersion: Emulgen 109P (manufactured by Kao Corporation, polyoxyethylene lauryl ether, HLB: 13.6) is dissolved in the electrolyte so as to have a concentration of 5% by weight to obtain a dispersion.
Dispersion conditions: 10 mg of a measurement sample is added to 5 mL of the above dispersion, and dispersed for 1 minute with an ultrasonic disperser, then 25 mL of electrolyte is added, and further dispersed for 1 minute with an ultrasonic disperser. Prepare a dispersion.
Measurement conditions: By adding the sample dispersion to 100 mL of the electrolytic solution, the particle size of 30,000 particles is adjusted to a concentration that can be measured in 20 seconds, and then 30,000 particles are measured, Determine the volume median particle size (D ₅₀ ).

<Purification example of rosin>
1000 g of tall rosin was added to a 2000 mL-distillation flask equipped with a fractionation tube, reflux condenser and receiver, and distilled under a reduced pressure of 1 kPa, and the distillate at 195 to 250 ° C. was collected as the main fraction. . Hereinafter, tall rosin subjected to purification is referred to as unpurified rosin, and rosin collected as a main fraction is referred to as purified rosin.

  20 g of rosin was pulverized for 5 seconds with a coffee mill (National MK-61M), and 0.5 g was measured in a headspace vial (20 mL) after passing through a 1 mm sieve. Table 1 shows the results of sampling the headspace gas and analyzing the unpurified rosin and impurities in the purified rosin by the headspace GC-MS method.

[Measurement conditions for headspace GC-MS method]
A. Headspace sampler (Agilent, HP7694)
Sample temperature: 200 ℃
Loop temperature: 200 ° C
Transfer line temperature: 200 ° C
Sample heating equilibration time: 30min
Bayal pressurized gas: Helium (He)
Bayal pressurization time: 0.3min
Loop filling time: 0.03min
Loop equilibration time: 0.3min
Injection time: 1min

B. GC (gas chromatography) (Agilent, HP6890)
Analytical column: DB-1 (60m-320μm-5μm)
Carrier: Helium (He)
Flow rate condition: 1mL / min
Inlet temperature: 210 ° C
Column head pressure: 34.2kPa
Injection mode: split
Split ratio: 10: 1
Oven temperature condition: 45 ℃ (3min) -10 ℃ / min-280 ℃ (15min)

C. MS (mass spectrometry) (Agilent, HP5973)
Ionization method: EI (electron ionization) method Interface temperature: 280 ℃
Ion source temperature: 230 ° C
Quadrupole temperature: 150 ° C
Detection mode: Scan 29-350m / z

<Measurement of saturation SP value of acrylic acid-modified rosin using unpurified rosin>
Add 332 g (1 mol) of unpurified rosin (SP value: 77.0 ° C) and 72 g (1 mol) of acrylic acid to a 1000 mL flask equipped with a fractionation tube, reflux condenser, and receiver. After heating up over 8 hours and confirming that the SP value did not increase at 230 ° C, unreacted acrylic acid and low-boiling substances were distilled off under reduced pressure at 230 ° C and 5.3 kPa. A modified rosin was obtained. The SP value of the resulting acrylic acid-modified rosin, that is, the saturated SP value of the acrylic acid-modified rosin using unpurified rosin was 110.1 ° C.

<Measurement of saturation SP value of acrylic acid-modified rosin using purified rosin>
Purified rosin (SP value: 76.8 ° C) 338g (1 mol) and acrylic acid 72g (1 mol) and acrylic acid 72g (1 mol) were added to a 1000ml flask equipped with a fractionation tube, reflux condenser and receiver. After increasing the temperature over time and confirming that the SP value did not increase at 230 ° C, unreacted acrylic acid and low-boiling substances were distilled off at 230 ° C under a reduced pressure of 5.3kPa to modify acrylic acid. I got rosin. The SP value of the obtained acrylic acid-modified rosin, that is, the saturated SP value of the acrylic acid-modified rosin using purified rosin was 110.4 ° C.

<Production Example 1 of Acrylic Acid-Modified Rosin>
Purified rosin (SP value: 76.8 ° C) 6084 g (18 mol) and acrylic acid 907.9 g (12.6 mol) were added to a 10 L flask equipped with a fractionation tube, reflux condenser and receiver, and the temperature was increased from 160 ° C to 220 ° C. After heating for 8 hours and reacting at 220 ° C. for 2 hours, distillation was further performed under reduced pressure at 220 ° C. and 5.3 kPa to obtain acrylic acid-modified rosin A. The acrylic acid-modified rosin A had an SP value of 110.4 ° C., a glass transition point of 57.1 ° C., and an acrylic acid modification degree of 100.

<Resin production examples 1 to 7>
A fractionation tube with hot water of 98 ° C., equipped with a reflux condenser that was passed through cold water at room temperature, an carboxylic acid component other than the alcohol component, trimellitic anhydride and esterification catalyst shown in Table 2, and nitrogen Place in a 5 liter four-necked flask equipped with an introduction tube, dehydration tube, stirrer, and thermocouple, conduct a polycondensation reaction at 160 ° C for 2 hours in a nitrogen atmosphere, and then increase the temperature to 210 ° C over 6 hours Thereafter, the reaction was carried out at 66 kPa for 1 hour. After cooling to 200 ° C, the trimellitic anhydride shown in Table 2 is added and reacted at normal pressure (101.3 kPa) for 1 hour, then heated to 210 ° C until the desired softening point is reached at 40 kPa. Reaction was performed and polyester (resin 1-7) was obtained.

<Resin production example 8>
Equipped with reflux condenser, nitrogen introduction pipe, dehydration pipe, dropping funnel, stirrer, and thermocouple through which the alcohol components, carboxylic acid components other than trimellitic anhydride and esterification catalyst shown in Table 2 were passed through cold water at room temperature The styrene, 2-ethylhexyl acrylate, acrylic acid and di-t-butyl peroxide shown in Table 2 were added from a dropping funnel under a nitrogen atmosphere at 150 ° C. for 2 hours under a nitrogen atmosphere. After dropping the mixture, an aging reaction was performed at 150 ° C. for 2 hours. Thereafter, the temperature was raised to 230 ° C. and a condensation polymerization reaction was carried out for 8 hours. After cooling to 210 ° C, the trimellitic anhydride shown in Table 2 was added and reacted at normal pressure (101.3 kPa) for 1 hour, then the temperature was raised to 210 ° C and the desired softening point was reached at 40 kPa. To obtain a hybrid resin (resin 8) comprising a polyester unit and a vinyl resin unit.

<Examples 1-3 and Comparative Examples 1-3>
Binder resin shown in Table 3, carbon black "MOGUL L" (Cabot) 4 parts by weight, negative charge control agent "Bontron S-34" (Orient Chemical Industries) 1 part and polypropylene wax "NP" -105 "(Mitsui Chemicals, melting point: 105 ° C) 1 part by weight was mixed thoroughly with a Henschel mixer, then using a co-rotating twin screw extruder, the roll rotation speed was 200r / min, and the heating temperature in the roll was Melt-kneaded at 80 ° C. The obtained melt-kneaded product was cooled and coarsely pulverized, then pulverized with a jet mill and classified to obtain a powder having a volume median particle size (D ₅₀ ) of 8.0 μm.

  To 100 parts by weight of the obtained powder, 1.0 part by weight of “Aerosil R-972” (manufactured by Nippon Aerosil Co., Ltd., hydrophobizing agent: DMDS, number average particle diameter: 16 nm) was added as an external additive. The toner was obtained by mixing.

Test Example 1 [Preservation]
Evaluation of thermal storage stability Fill a glass container with toner and leave it in a constant temperature bath at 60 ° C. for 4 hours. The toner was cooled to 24 ° C. and the penetration was measured by a penetration test (JIS K2235-1991). The higher the penetration value, the more the toner is not aggregated and the better the storage stability. The results are shown in Table 3.

[Evaluation criteria for storage stability]
4: Penetration 20mm above 3: Penetration 15mm or more, less than 20mm 2: Penetration 10mm or more, less than 15mm 1: Penetration less than 10mm

Test Example 2 [Low-temperature fixability and offset resistance]
The toner is mounted on the printer “Page Presto N-4” (Casio Computer Co., Ltd., fixing: contact fixing method, developing method: non-magnetic one-component developing method, developing roll diameter: 2.3 cm), and the toner adhesion amount is 0.6 mg / An unfixed image was obtained by adjusting to cm ² . The fixing machine (fixing speed: 500mm / s) was improved so that the fixing machine of the AR-505 (Sharp Co.) copier with the contact fixing method can be fixed outside the machine. The fixing roll was fixed by fixing the unfixed image while increasing the temperature of the fixing roll from 100 ° C. to 250 ° C. in 10 ° C. increments.

  The image obtained at each fixing temperature was pasted with UNICEF Cellophane (Mitsubishi Pencil Co., Ltd., width 18 mm, JISZ-1522), passed through the fixing roll of the fixing machine set to 30 ° C., and then the tape was applied. The optical reflection density before and after peeling and tape peeling was measured using a reflection densitometer “RD-915” (manufactured by Macbeth). The fixing roller temperature at which the ratio between the two (after peeling / before peeling) first exceeded 95% was set as the minimum fixing temperature, and the low-temperature fixing property was evaluated according to the following evaluation criteria. Also, the hot offset occurrence temperature was confirmed at the same time, and the offset resistance was evaluated according to the following evaluation criteria. The results are shown in Table 3.

[Evaluation criteria for low-temperature fixability]
5: Minimum fixing temperature is less than 150 ° C. 4: Minimum fixing temperature is 150 ° C. or more and less than 160 ° C. 3: Minimum fixing temperature is 160 ° C. or more and less than 170 ° C. 2: Minimum fixing temperature is 170 ° C. or more and less than 180 ° C. 1: Minimum fixing temperature of 180 ° C or higher

[Evaluation criteria for offset resistance]
4: Hot offset generation temperature is 240 ° C or higher 3: Hot offset generation temperature is 230 ° C or higher and lower than 240 ° C 2: Hot offset generation temperature is 190 ° C or higher and lower than 230 ° C 1: Hot offset generation temperature is lower than 190 ° C

Test Example 3 [Wax Dispersibility]
Using a transmission electron microscope, the sample after melting and kneading the toner was measured for 50 points of wax dispersion (average value of major axis and minor axis is the dispersed particle diameter) in a field of view of 100,000 times. The average value was defined as the average dispersed particle size. The results are shown in Table 3.

[Evaluation criteria for wax dispersibility]
4: Wax average dispersion diameter of less than 0.5 μm 3: Wax average dispersion diameter of 0.5 μm or more and less than 1.0 μm 2: Wax average dispersion diameter of 1.0 μm or more, less than 3.0 μm 1: Wax average dispersion diameter of 3.0 μm or more

Test Example 4 [Crushability]
A resin powder is obtained which passes through a 16-mesh sieve (aperture: 1.0 mm) but does not pass through a 22-mesh sieve (aperture: 710 μm). 30g of the classified resin powder was ground for 10 seconds with a coffee mill (PHILIPS, HR-2170 type), then passed through a 30 mesh sieve (opening: 500μm), and the weight of the resin powder not passing through (A) g Weigh accurately. From this weight, the residual rate was determined by the following formula, and this operation was performed three times to determine the average value. The results are shown in Table 3.
Residual rate (%) = (A [g] /30.0 [g]) x 100

[Evaluation criteria for grindability]
4: Average survival rate is less than 10.0% 3: Average survival rate is 10.0% or more and less than 15.0% 2: Average survival rate is 15.0% or more and less than 20.0% 1: Average survival rate is 20.0% or more Is

  From the above results, polyester resin obtained using 1,2-propanediol and (meth) acrylic acid-modified rosin, 1,2-propanediol and 1,3-propanediol, and purified rosin are used. The toners of the examples using the polyester resins obtained in this way are excellent in all of the low-temperature fixability, the offset resistance, the grindability, the dispersibility of the internal additives and the storage stability as compared with the toners of the comparative examples. I understand.

The toner of the present invention is suitably used for developing a latent image formed in electrophotography, electrostatic recording method, electrostatic printing method and the like.

Claims (6)

A toner comprising a polyester resin (A) and a polyester resin (B) having a softening point higher than that of the polyester resin (A) by 10 ° C. or more as a binder resin, the polyester resin (A) Has a polyester unit obtained by polycondensation of an alcohol component containing 65 mol% or more of 1,2-propanediol in a divalent alcohol component and a carboxylic acid component containing (meth) acrylic acid-modified rosin. An alcohol component containing 70 mol% or more of 1,2-propanediol and 1,3-propanediol in the divalent alcohol component, and the headspace GC-MS. peak intensity of hexanoic acid is at 0.8 × 10 ⁷ or less at law, the peak intensity of pentanoic acid is at 0.4 × 10 ⁷ or less, spinning peak intensity of benzaldehyde is 0.4 × 10 ⁷ or less A carboxylic acid component containing a rosin is a resin having a polyester unit obtained by condensation polymerization, toner.   The toner according to claim 1, wherein the (meth) acrylic acid-modified rosin in the polyester-based resin (A) has a (meth) acrylic acid modification degree of 5 to 105.   In the alcohol component of the polyester resin (B), the molar ratio of 1,2-propanediol to 1,3-propanediol (1,2-propanediol / 1,3-propanediol) is 70/30 to 99/1. The toner according to claim 1, wherein   The polyester resin (A) and / or polyester resin (B) contains a trihydric or higher polyhydric alcohol and / or a tricarboxylic acid polyvalent carboxylic acid compound. The toner according to claim 1.   Polyester resin (A) and / or polycondensation of polyester resin (B) with an alcohol component and a carboxylic acid component in the presence of a titanium compound and / or a tin (II) compound having no Sn-C bond. The toner according to claim 1, wherein   The toner according to claim 1, further comprising a composite resin having a condensation polymerization resin unit and an addition polymerization resin unit as the binder resin.