JPH07333892A - Toner fro developing electrostatic charge image - Google Patents

Abstract

PURPOSE:To obtain an electrostatic charge image developing toner excellent in low temp. fixing property and offset preventing effect which is suitable for a contact heating method by incorporating a structural material obtd. by the reaction of a low mol.wt. resin and at least one of long-chain aliphatic polyol, long-chain aliphatic diol and long-chain aliphatic monoalcohol into a polyester resin. CONSTITUTION:This electrostatic charge image developing toner consists of at least a binder resin essentially comprising polyester resin and a coloring agent. The polyester resin contains such a structural material obtd. by the reaction of the low mol. polyester resin and at least one of long-chain aliphatic polyol, long-chain aliphatic dial and long-chain aliphatic monoalcohol. The low mol.wt. resin of the polyester resin is obtd. by condensation polymn. of a diol component, and dicarboxylic acid or its anhydride or lower alkyl ester, and polyol or polycarboxylic acid. A low mol.wt. resin having <=3000 number average mol.wt. (Mn) is preferably used.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrostatic charge image developing toner used in electrophotography, electrostatic recording, electrostatic printing and the like.

[0002]

2. Description of the Related Art In electrophotography, electrostatic recording, electrostatic printing, etc., an electrostatic charge image formed on an electrostatic charge image support is formed by toner particles containing a binder resin and a colorant as main components. To be visualized. The visualized image is fixed as it is on the electrostatic image support, or is transferred to a transfer paper and then fixed. Therefore, the toner for developing an electrostatic charge image is required to have not only developability on an electrostatic charge image support but also good transferability and fixability on a transfer sheet. Further, in recent years, from the viewpoint of energy saving, it is also required that fixing can be performed with low energy. By the way, the heat fixing method of the toner for developing an electrostatic image is roughly classified into a non-contact heating method such as oven fixing and a contact heating method such as heating roller fixing. The contact heating fixing method has an advantage that the heat efficiency is high and the fixing unit can be downsized without using a large electric power for the fixing unit. Therefore, it is a preferable method from the viewpoint of energy saving. However, this method has a problem that an offset occurs. Offset is a phenomenon in which part of the toner for developing an electrostatic image that forms an image is transferred to the surface of the heat fixing roll during fixing, and this is transferred onto the transfer paper that is sent next, thus contaminating the image. Say. Various proposals have been made to prevent this offset phenomenon. One of them is a proposal to incorporate a compound having releasability such as wax into the toner for developing an electrostatic image. Although this proposal has been widely practiced, when this compound was blended, there was a problem that wax adhered to the photoreceptor, so-called filming was likely to occur, and storage stability was lacking. There is also a proposal to use a high molecular weight polymer as a resin forming a toner for developing an electrostatic image. However, in this case, although offset can be prevented, there is a problem in that the softening point becomes high, the fixing temperature becomes high, and the resin is tough, so that it becomes difficult to pulverize the toner during manufacturing.

In order to solve these problems, a toner for developing an electrostatic charge image has been proposed which uses a vinyl polymer such as styrene having a wide molecular weight distribution from low molecular weight to high molecular weight as a binder resin. However, this toner for developing an electrostatic image is satisfactory in offset prevention and fixability, but not in low temperature fixability. On the other hand, in the case of a condensation resin represented by a polyester resin, a polymer having a relatively low molecular weight can be obtained. Therefore, there has been proposed a toner for developing an electrostatic image capable of fixing at a low temperature using a polyester resin as a binder resin. However, this electrostatic image developing toner has a problem that offset occurs at a high fixing temperature. Further, a toner for developing an electrostatic image, which is a mixture of a high molecular weight vinyl polymer and a low molecular weight polyester resin, is disclosed in JP-A-54-11424.
5, JP-A-58-11955, JP-A-58
No. 14147, for example. This electrostatic image developing toner has some effect in preventing offset when the temperature of the heat fixing roll rises above a predetermined fixing temperature, but it is difficult to uniformly mix both resins, and therefore triboelectrification Had a problem that it was likely to become uneven. Further, a toner for developing an electrostatic charge image using a resin having a crosslinked structure using a trivalent or higher valent alcohol and / or a trivalent or higher carboxylic acid as a monomer component of a polyester resin is disclosed in JP-A-54-86342. Kaisho 5
6-1952, JP-A-56-21136, JP-A-56-
168660, JP-A-57-37353, JP-A-58-
14146, JP-A-59-30542 and JP-A-61-1.
05561, JP 61-105563, JP 61-
No. 124961, Japanese Patent Laid-Open No. 61-275769, and the like. However, even in the toner for developing electrostatic images using these polyester resins, the amount of polyhydric alcohol or polycarboxylic acid blended in the resin is 30.
When it was at most mol%, the crosslinking reaction did not proceed sufficiently and the effect of preventing offset was insufficient. When it is mixed in an amount of more than 30 mol%, an offset-preventing effect is recognized, but unreacted alcoholic hydroxyl groups and carbonyl groups of carboxylic acids are likely to remain, and the electrostatic resistance of the toner for developing an electrostatic charge image is low. It had a problem of a significant decrease.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to solve the problems of the above-mentioned conventional toners for developing an electrostatic charge image, and to provide a toner for developing an electrostatic charge image having good developability, transferability and fixability. To provide. More specifically, the present invention provides a toner for developing an electrostatic charge image, which is excellent in low-temperature fixability and is excellent in offset prevention effect and suitable for a contact heating system.

[0005]

The present invention provides a toner for developing an electrostatic charge image, which comprises at least a binder resin containing a polyester resin as a main component and a colorant, and a low molecular weight product of the resin in the polyester resin. Long-chain aliphatic polyol,
Provided is a toner for developing an electrostatic charge image, which comprises a structure obtained by reacting at least one selected from a long-chain aliphatic diol and a long-chain aliphatic monoalcohol. Hereinafter, the present invention will be described in detail. In order to produce the polyester resin which is a feature of the present invention, a low molecular weight product is formed in advance with components other than the long-chain aliphatic polyol, the long-chain aliphatic diol and the long-chain aliphatic monoalcohol, and the second step reaction is carried out. At least one selected from long-chain aliphatic polyols, long-chain aliphatic diols, and long-chain aliphatic monoalcohols can be added and reacted. A structure obtained by reacting a low-molecular weight substance with at least one selected from a long-chain aliphatic polyol, a long-chain aliphatic diol, and a long-chain aliphatic monoalcohol by such a production method, and a long-chain aliphatic polyol A polyester resin in which a long-chain aliphatic diol or a polymer obtained by condensation polymerization without reacting with a long-chain aliphatic monoalcohol is mixed is obtained. in this case,
Reacting means cross-linking and grafting a long-chain aliphatic polyol with a low-molecular weight substance when only a long-chain aliphatic polyol is added, and a long-chain fat when only a long-chain aliphatic diol is added. It means to crosslink and graft a group diol and a low molecular weight body, and when only a long chain aliphatic monoalcohol is added, it means to graft a long chain aliphatic monoalcohol to a low molecular weight body,
When a long-chain aliphatic polyol, a long-chain aliphatic diol and a long-chain aliphatic monoalcohol are added, a long-chain aliphatic polyol, a long-chain aliphatic diol and a long-chain aliphatic monoalcohol are cross-linked and grafted with a low molecular weight substance. Means to let. By using at least one selected from a long-chain aliphatic polyol, a long-chain aliphatic diol, and a long-chain aliphatic monoalcohol as a side chain or a cross-linking agent component of a polyester resin, or as a side chain and a cross-linking agent component, Unlike the case where it is used for a chain, it is possible to prevent a decrease in the glass transition point of the binder resin. In the present invention, by incorporating a structure obtained by reacting a low molecular weight substance with at least one selected from a long-chain aliphatic polyol, a long-chain aliphatic diol, and a long-chain aliphatic monoalcohol, a polyester resin The elasticity is improved and the offset prevention effect at low temperature fixing is improved.

The low molecular weight polyester resin of the present invention is obtained by polycondensing a composition comprising (a) a diol component and a dicarboxylic acid or an anhydride thereof or a lower alkyl ester thereof as a main component, (b) ) A compound obtained by polycondensing a composition containing a diol component, a dicarboxylic acid or its anhydride or its lower alkyl ester, and a phenolic hydroxyl group-containing carboxylic acid or its anhydride or its lower alkyl ester as main components,
(C) A diol component, a polycarboxylic acid or an anhydride thereof or a lower alkyl ester thereof and a polyol or a polycarboxylic acid which are polycondensed, (d) a diol component, a dicarboxylic acid or an anhydride thereof or a lower alkyl ester thereof. , A phenolic hydroxyl group-containing carboxylic acid or an anhydride thereof or a lower alkyl ester thereof and a polycondensation of a polyol or a polycarboxylic acid, and those having a number average molecular weight (Mn) of 3,000 or less are preferably used. Number average molecular weight (M
It is preferable that n) is 1500 to 3000. By using a low molecular weight substance having a number average molecular weight (Mn) of 3000 or less, a long-chain aliphatic polyol, a long-chain aliphatic diol,
At least one selected from long-chain aliphatic monoalcohols can be reacted well. Number average molecular weight (M
When n) is greater than 3000, it tends to be difficult to react at least one selected from long-chain aliphatic polyols, long-chain aliphatic diols, and long-chain aliphatic monoalcohols. In the present invention, the number average molecular weight (Mn) can be measured by a known ordinary method and can be measured by gel permeation chromatography (GPC) under the following conditions. That is, a solvent (tetrahydrofuran) is caused to flow at a flow rate of 1 ml / min at a temperature of 25 ° C., and 8 mg of a tetrahydrofuran sample solution having a concentration of 0.4 gr / dl is injected as a sample weight for measurement. Further, in measuring the molecular weight of a sample, the measurement conditions in which the molecular weight distribution of the sample is included within the range in which the logarithm of the molecular weight and the count number of the calibration curve prepared by several kinds of monodisperse polystyrene standard samples are linear Select. Further, in this measurement, the reliability of the measurement is based on the NBS706 polystyrene standard sample (Mw = 28.8 × 10 ⁴ , Mn = 1) measured under the above-mentioned measurement conditions.
Mw / Mn of 3.7 × 10 ⁴ , Mw / Mn = 2.11)
Can be confirmed by becoming 2.11 ± 0.10. Examples of the diol component include diethanolamine, ethylene glycol, diethylene glycol, propylene glycol, isoprene glycol, octane diol,
2,2-diethyl-1,3-propanediol, spiroglycol, neopentyl glycol, 1,3-butanediol, 1,4-butanediol, 2-butyl-2-
Ethyl-1,3-propanediol, 1,6-hexanediol, hexylene glycol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, hydrobenzoin, bis (β-hydroxyethyl) terephthalate, Examples thereof include bis (hydroxybutyl) terephthalate, polyoxyethylenated bisphenol A, polyoxypropyleneated bisphenol A, polyoxyethylenated biphenol, and polyoxypropyleneated biphenol.

As the dicarboxylic acid, fumaric acid,
Maleic acid, succinic acid, itaconic acid, mesaconic acid, citraconic acid, glutaconic acid, phthalic acid, isophthalic acid,
Terephthalic acid, cyclohexanedicarboxylic acid, cyclohexenedicarboxylic acid, adipic acid, sebacic acid, dodecanedioic acid, naphthalenedicarboxylic acid, biphenyl-4,4
-Dicarboxylic acid, 2,3-piperazine-dicarboxylic acid,
Iminodicarboxylic acid, imidazole-4,5-dicarboxylic acid, piperidinedicarboxylic acid, N-phenylpyrazoledicarboxylic acid, pyridinedicarboxylic acid, carbazole-3,6-dicarboxylic acid, 9-methylcarbazole-
Examples thereof include 3,6-dicarboxylic acid, carbazole-3,6-dibutyric acid, carbazole-3,6-γ, γ′-diketobutyric acid, and the anhydrides thereof or lower alkyl esters thereof. Further, as the phenolic hydroxyl group-containing dicarboxylic acid, 4-hydroxyisophthalic acid,
Examples thereof include 5-hydroxyisophthalic acid, 4,6-dihydroxyisophthalic acid, 2,5-dihydroxy-1,4-benzenediacetic acid, chelidamic acid, and bis (2-hydroxy-3-carboxyphenyl) methane. Anhydrides or lower alkyl esters thereof can be used. Examples of the polyol include glycerin, trimethylolpropane, trimethylolethane, triethanolamine, pentaerythritol, sorbitol, glycerol, 1,3,5-trihydroxymethylbenzene and the like. As the polycarboxylic acid, trimellitic acid, pyromellitic acid, 1,2,4-cyclohexanetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, 2,5,7-naphthalenedicarboxylic acid, pyridinetricarboxylic acid, Pyridine-2,3,4,6-tetracarboxylic acid, 1,2,7,8-tetracarboxylic acid, butanetetracarboxylic acid and the like can be mentioned, and their anhydrides or their lower alkyl esters can be used. The compounding ratio of the diol component, the dicarboxylic acid or its anhydride or its lower alkyl ester in the low molecular weight compound can be arbitrarily changed in order to control the hydroxyl value and acid value of the resin.

Long-chain aliphatic polyols constituting the present invention,
When the long-chain aliphatic diol or the long-chain aliphatic monoalcohol has 12 or more carbon atoms, it is more preferable in terms of the effects of improving the elasticity of the resin and preventing offset. When the number of carbon atoms is 12 or more, at least one selected from long-chain aliphatic polyols, long-chain aliphatic diols, and long-chain aliphatic monoalcohols is added to the low molecular weight alcohol component in an amount of 0.
It is only necessary to use 1 to 50 mol%, and the glass transition temperature of the toner for developing an electrostatic charge image can be maintained within a range usually used (50 ° C. or higher). There is no problem. If the number of carbon atoms is less than 12, the amount of at least one selected from long-chain aliphatic polyols, long-chain aliphatic diols and long-chain aliphatic monoalcohols must be increased in order to obtain the required elasticity. No
It is difficult to maintain the glass transition point of the toner for developing an electrostatic charge image, which is usually required, that is, the temperature is less than 50 ° C., which may cause a problem in storage stability of the toner for developing an electrostatic charge image. Even if a long-chain aliphatic polyol having 12 or more carbon atoms, a long-chain aliphatic diol, or a long-chain aliphatic monoalcohol is used, the amount is less than 0.1 mol% with respect to the low molecular weight alcohol component. And the effect of improving the elasticity of polyester resin is not so great. On the other hand, if at least one selected from a long-chain aliphatic polyol having a carbon number of 12 or more, a long-chain aliphatic diol, and a long-chain aliphatic monoalcohol is used in an amount of more than 50 mol% with respect to the low molecular weight alcohol component, Although elasticity is obtained, the glass transition temperature of the binder resin is lowered, which may cause a problem in storage stability of the toner for developing an electrostatic image.

Furthermore, by incorporating a structure in which at least one selected from a long-chain aliphatic polyol, a long-chain aliphatic diol and a long-chain aliphatic monoalcohol is reacted with a low molecular weight substance in the polyester resin, The compatibility is improved when a compound having releasability such as wax is contained in the electrostatic image developing toner. The long-chain aliphatic polyol, long-chain aliphatic diol, or long-chain aliphatic monoalcohol used in the present invention has 1 carbon atom having a reactive group such as a hydroxyl group.
When it is an alkane or alkenyl compound having two or more reactive groups and two or more reactive groups, the number of carbon atoms is 6 or more, preferably 10 or more. Further, the carbon connecting the reactive groups may be linear or may have a branched structure.
The following compounds are exemplified as the long-chain aliphatic polyol component. Glycerin-tri-12-hydroxystearate, galactitol-hexapolyisopropyl ether and the like can be used. Examples of the long chain aliphatic diol include the following compounds. 1,12-dodecanediol (C12), 1,14 tetradecanediol (C1)
4), polyethylene glycol, polytetramethylene glycol and the like can be used. The following compounds are exemplified as the long-chain aliphatic monoalcohol. 1-dodecanol (C12), pentadecanol (C15), hexadecanol (C16), 9,12-octadecanedienol (C18), 10,12-pentacosadiin-1-ol ( C25) etc. can be used. The carbon number of the long-chain aliphatic polyol, the long-chain aliphatic diol or the long-chain aliphatic monoalcohol or the content of the unsaturated group, etc.
It can be arbitrarily changed for the purpose of adjusting the thermophysical properties of the polyester resin.

The polyester resin used in the present invention is
It is desirable that the glass transition temperature measured by a differential scanning calorimeter (DSC) is 50 ° C. or higher and the flow softening point measured by a flow tester is 80 ° C. or higher. In this case, if the glass transition temperature is lower than 50 ° C., the storage stability of the electrostatic charge image developing toner tends to be lowered, and if the flow softening point is lower than 80 ° C., the storage stability of the electrostatic charge image developing toner is lowered. Cheap. The toner for developing an electrostatic charge image of the present invention comprises a binder resin containing a colorant, and if necessary, a charge control agent, a magnetic powder or the like dispersed and mixed,
It is crushed and manufactured. Examples of the colorant include carbon black, aniline blue, phthalocyanine blue, quinoline yellow, malachite green, lamp black, rhodamine-B and quinacridone. Usually, 1 to 20% by weight is added to the binder resin. Charge control agents include those for positive charging and those for negative charging. Examples of positive charging agents include nigrosine dyes, ammonium salts, pyridinium salts, and azines. These charge control agents are usually added in an amount of 0.1 to 10% by weight based on the polyester resin. For negative charging, a chromium complex, an iron complex, etc. are exemplified. In the present invention, other binder resins such as styrene-acrylic copolymer resin may be mixed and used.

[0011]

EXAMPLES The present invention will now be described in more detail with reference to examples. <Example 1> Polyoxyethylenated bisphenol A
(2,2′-bis [4- (2-hydroxyethyleneoxy) phenyl] propane) 316 g (1 mol), isophthalic acid 91.3 g (0.55 mol), phthalic anhydride 8
1.4 g (0.55 mol), butanetetracarboxylic acid 4.1 g (0.02 mol), dibutyltin oxide 2.5 g
Was placed in a four-necked round-bottomed flask equipped with a stirrer, a condenser, and a nitrogen gas introduction tube, and heated to 200 ° C. while introducing nitrogen gas from the nitrogen gas introduction tube to distill water to obtain a low molecular weight substance. . Then, 8.7 g (0.05 mol, 5 mol% relative to the alcohol component) of 1,12-dodecanediol was added to this low molecular weight substance, and the reaction was further advanced at 230 ° C. for 3 hours to obtain a polyester resin. The glass transition point of this polyester resin measured by DSC was 68 ° C., the melting start temperature measured by a Koka type flow tester was 105 ° C., and the flow softening point was 143 ° C. The number average molecular weight (Mn) of the low-molecular weight substance before adding 1,12-dodecanediol was 1600, and the number average molecular weight (M of the polyester resin obtained by adding 1,12-dodecanediol was (M).
n) was 6800. Next, a mixture having the following composition was melt-kneaded at about 150 ° C. using a biaxial kneader. After cooling the molten mixture, it was pulverized and classified to have an average particle size of 8.5.
Thus, negatively charged toner particles having a size of μm were obtained. The toner particles 10
0.5 part by weight of hydrophobic colloidal silica was externally added to 0 part by weight with a Henschel mixer to obtain a toner for developing an electrostatic image of the present invention.・ 100 parts by weight of the above polyester resin ・ 8 parts by weight of carbon black (Mitsubishi Chemical Co., Ltd., trade name: MA-100) ・ 2 parts by weight of iron complex salt dye <Example 2> Polyoxyethylenated bisphenol A
(2,2′-bis [4- (2-hydroxyethyleneoxy) phenyl] propane) 316 g (1 mol), isophthalic acid 149 g (0.9 mol), trimellitic anhydride 1
9.2 g (0.1 mol), dibutyl tin oxide 2.5 g,
4 equipped with stirrer, condenser and nitrogen gas inlet tube
The mixture was placed in a two-necked round bottom flask and heated to 200 ° C. while introducing nitrogen gas from a nitrogen gas introducing tube to distill water to obtain a low molecular weight substance. Then, 4 g (0.02 mol, 2 mol% with respect to the alcohol component) of polyethylene glycol (molecular weight about 200) was added to this low molecular weight substance, and the mixture was heated under a nitrogen stream to give 230
The reaction was allowed to proceed at ℃ for 3 hours to obtain a polyester resin. The glass transition temperature of the obtained polyester resin was 66 ° C., the melting start temperature was 100 ° C., and the flow softening point was 135 ° C.
The number average molecular weight (Mn) of the low molecular weight product before adding polyethylene glycol was 2000, and the number average molecular weight (Mn) of the polyester resin obtained by adding polyethylene glycol was 7,200. Next, an electrostatic charge image developing toner of the present invention was obtained in the same manner as in Example 1 except that the polyester resin in Example 1 was replaced with the above polyester resin.

Example 3 Polyoxyethylenated bisphenol A (2,2'-bis [4- (2-hydroxyethyleneoxy) phenyl] propane) 316 g (1 mol), butane tetracarboxylic acid 11.7 g (0 0.05 mol), 148 g (1 mol) of phthalic anhydride, and 5 g of dibutyltin oxide were placed in a 4-neck round bottom flask equipped with a stirrer, a condenser and a nitrogen gas introducing pipe, and nitrogen gas was introduced from the nitrogen gas introducing pipe. While heating to 200 ° C., water was distilled off to obtain a low molecular weight substance. Then, 15 g (0.02 mol, based on the alcohol component) of a long-chain aliphatic diol (manufactured by Sanyo Chemical Industry Co., Ltd., trade name: Sannix SP-750) consisting of a hexafunctional polyether polyol having a molecular weight of about 750 was added to this low molecular weight substance. 1.905 mol%) and under a nitrogen stream 23
The reaction was further continued at 0 ° C. for 3 hours to obtain a polyester resin.
The glass transition temperature of the obtained polyester resin is 64 ° C.,
The melting start temperature was 110 ° C and the flow softening point was 138 ° C. The number average molecular weight (Mn) of the low molecular weight product before adding the long chain aliphatic diol was 1700, and the number average molecular weight (Mn) of the polyester resin obtained by adding the long chain aliphatic diol was 8000. there were. Next, an electrostatic charge image developing toner of the present invention was obtained in the same manner as in Example 1 except that the polyester resin in Example 1 was replaced with the above polyester resin. <Example 4> Polyoxyethylenated bisphenol A
(2,2′-bis [4- (2-hydroxyethyleneoxy) phenyl] propane) 252.8 g (0.8 mol), bisphenol A / propylene oxide (2,2)
2'-bis [4- (2-hydroxypropyleneoxy)
(Phenyl] propane) 68.8 g (0.2 mol), terephthalic acid 99.6 g (0.6 mol), isophthalic acid 6
6.4 g (0.4 mol), trimellitic acid 21 g (0.
1 mol) and 5 g of dibutyltin oxide were placed in a four-necked round bottom flask equipped with a stirrer, a condenser and a nitrogen gas introducing pipe, while introducing nitrogen gas from the nitrogen gas introducing pipe to 200
It was heated to ℃ and distilled water to obtain a low molecular weight product. Then, 18.6 g (0.1 mol, 10 mol% with respect to the alcohol component) of 1-dodecanol was added to this low molecular weight substance, and the reaction was further advanced at 230 ° C. for 3 hours under a nitrogen stream to obtain a polyester resin. The glass transition temperature of the obtained polyester resin is 65 ° C., the melting start temperature is 123 ° C., and the flow softening point is 158.
It was ℃. The number average molecular weight (Mn) of the low molecular weight substance before adding 1-dodecanol was 1800, and
-The number average molecular weight (Mn) of the polyester resin obtained by adding dodecanol was 7400. Next, an electrostatic charge image developing toner of the present invention was obtained in the same manner as in Example 1 except that the polyester resin in Example 1 was replaced with the above polyester resin. <Example 5> Polyoxyethylenated bisphenol A
(2,2′-bis [4- (2-hydroxyethyleneoxy) phenyl] propane) 252.8 g (0.8 mol), bisphenol A / propylene oxide (2,2)
2'-bis [4- (2-hydroxypropyleneoxy)
(Phenyl] propane) 68.8 g (0.2 mol), terephthalic acid 99.6 g (0.6 mol), isophthalic acid 6
6.4 g (0.4 mol), trimellitic acid 21 g (0.
1 mol) and 5 g of dibutyltin oxide were placed in a four-necked round bottom flask equipped with a stirrer, a condenser and a nitrogen gas introducing pipe, while introducing nitrogen gas from the nitrogen gas introducing pipe to 200
It was heated to ℃ and distilled water to obtain a low molecular weight product. Then, 9.3 g of 1-dodecanol (0.05 mol, 5 mol% based on the alcohol component) and 10.1 g of 1,12-dodecanediol (0.05 mol, 5 mol based on the alcohol component) were added to the low molecular weight product. Mol%) was added, and the reaction was further advanced at 230 ° C. for 3 hours under a nitrogen stream to obtain a polyester resin. The glass transition temperature of the obtained polyester resin was 66 ° C., the melting start temperature was 120 ° C., and the flow softening point was 144 ° C. In addition, the number average molecular weight (Mn) of the low molecular weight substance before adding 1-dodecanol and 1,12-dodecanediol was 1700, and the polyester resin obtained by adding 1-dodecanol and 1,12-dodecanediol The number average molecular weight (Mn) was 8,100. Next, an electrostatic charge image developing toner of the present invention was obtained in the same manner as in Example 1 except that the polyester resin in Example 1 was replaced with the above polyester resin.

<Comparative Example 1> In Example 1, 1, 12
A polyester resin having a number average molecular weight (Mn) of 8000 was produced in the same manner except that dodecanediol was not added, and then a comparative electrostatic image developing toner was obtained. The glass transition temperature of this polyester resin was 68 ° C., the melting start temperature was 110 ° C., and the flow softening point was 143 ° C. Comparative Example 2 The number average molecular weight (Mn) was the same as in Example 2 except that polyethylene glycol was not added.
12,000 polyester resins were produced, and then a comparative electrostatic image developing toner was obtained. The glass transition temperature of this polyester resin is 72 ° C, the melting start temperature is 116 ° C,
The flow softening point was 148 ° C.

<Comparative Example 3> A polyester resin having a number average molecular weight (Mn) of 7500 was produced in the same manner as in Example 3 except that the long-chain aliphatic diol was not added, and then a toner for developing an electrostatic image for comparison was prepared. Got This polyester resin has a glass transition temperature of 75 ° C. and a melting start temperature of 11
The softening point was 2 ° C and the softening point was 140 ° C. <Comparative Example 4> A number average molecular weight (Mn) of 110 was obtained in the same manner as in Example 4, except that 1-dodecanol was not added.
No. 00 polyester resin was produced, and then a comparative electrostatic image developing toner was obtained. The glass transition temperature of this polyester resin was 74 ° C, the melting start temperature was 120 ° C, and the flow softening point was 148 ° C. Comparative Example 5 The polyester resin of Comparative Example 1 has 1,12-
8.7 g of dodecanediol (0.05 mol, 5 mol% with respect to the alcohol component) was added, the reaction was allowed to proceed at 230 ° C. for 4 hours to obtain a resin, and then the polyester resin of Comparative Example 1 was added to the above 1,12- A comparative electrostatic image developing toner was obtained in the same manner as in Comparative Example 1 except that the resin added with dodecanediol was used. The polyester resin had a number average molecular weight (Mn) of 7,700, a glass transition temperature of 66 ° C., a melting start temperature of 105 ° C. and a flow softening point of 128 ° C., but 1,12-dodecanediol was the polyester of Comparative Example 1. No reaction with the resin was observed, and the glass transition temperature was also lowered.

Next, the following items were tested for each of the electrostatic image developing toners obtained in the above Examples and Comparative Examples. (1) Non-Offset Temperature Region and Non-Offset Temperature Range First, 5 parts by weight of each electrostatic image developing toner and a ferrite carrier (trade name: DFC150S6 manufactured by Dowa Iron Powder Co., Ltd.) 95
A two-component type developer was prepared by mixing with a part by weight. Next, using the developer, a commercially available copying machine (manufactured by Sanyo Electric Co., Ltd., trade name: Z-133) was used to transfer the A4 transfer paper in a length of 2 cm and a width of 5
A plurality of cm-shaped belt-shaped unfixed images were prepared. Then, a heat fixing roll having a surface layer made of Teflon and a pressure fixing roll having a surface layer made of silicone rubber are paired and rotated, and a roll pressure is set to 1 Kg / cm ² and a roll speed is 200 mm / sec. The surface temperature of the heat fixing roll was changed stepwise, and the toner image on the transfer paper having the above-mentioned unfixed image was fixed at each surface temperature. At this time, it was observed whether or not the toner was smeared in the blank area, and the temperature range in which the smear did not occur was defined as the non-offset temperature range. Further, the difference between the maximum value and the minimum value in the non-offset temperature region was defined as the non-offset temperature width.

(2) Fixing Strength The surface temperature of the heat fixing roll of the fixing device was set to 130 ° C., and the toner image on the transfer paper on which the unfixed image was formed was fixed. Then, the image density of the formed fixed image is measured by a reflection densitometer (trade name: RD-91, manufactured by Macbeth Co.).
4), the fixed image was rubbed with a cotton pad, and the image density was measured in the same manner. The fixing strength was calculated from the obtained measured value by the following formula and used as an index of low energy fixing property. Fixing strength (%) = (image density of fixed image after rubbing / image density of fixed image before rubbing) × 100 Table 1 shows the test results of the above items.

[0017]

[Table 1]

As is clear from the test results of Table 1, the non-offset temperature region of the toner for developing an electrostatic image of the present invention does not cause an offset from a low temperature to a high temperature, and the non-offset temperature range is as wide as 100 ° C. It was confirmed that the width was wide and the range was practically sufficient. Also, the fixing temperature 1
Since the fixing strength at 30 ° C. is 87% or more and the fixing strength is practically sufficient, the low temperature fixing property was confirmed. On the other hand, in the comparative example, the offset occurs on the low temperature side, the non-offset temperature width is narrower than that of the electrostatic image developing toner of the present invention, and the offset occurs in all the comparative examples at the fixing temperature of 130 ° C. The fixing strength test was not conducted. The polyester resin used in the toner for developing an electrostatic image of Comparative Example 5 was prepared by adding a long-chain aliphatic diol, but the composition in the polyester resin and the long-chain aliphatic diol reacted well. No useful effect on the fixability of the toner was obtained. Further, a continuous copy test of up to 10,000 sheets was conducted using each developer and the copying machine of the example in the above item (1).
As a result, in all the examples, the amount of triboelectrification by the blow-off triboelectrification amount measuring device (manufactured by Toshiba Chemical Co.) was from -25 μc / g to -2 from the initial stage to 10000 sheets.
The image density changes from the initial value to 1000 μc / g.
It maintained 1.4 or more in the process of continuous copying up to 0 sheets, and the background fog in the non-image area measured by a color difference meter (Z-1001DP manufactured by Nippon Denshoku Co., Ltd.) was 0.6 or less, which is practically no problem. It was confirmed.

[0019]

The toner for developing an electrostatic charge image of the present invention can maintain a sufficient non-offset temperature region and can be fixed at a low temperature, has excellent fixing strength, and obtains a sufficient number of image densities. There is an effect that can be. Therefore, when the electrostatic image developing toner of the present invention is applied to a copying machine, a printer or the like, it is possible to reduce power consumption and reduce machine cost due to low roll pressure.
This has the effect of increasing the copying speed.

Claims (4)

[Claims] 1. A toner for developing an electrostatic charge image comprising at least a binder resin containing a polyester resin as a main component and a colorant, wherein a low molecular weight product of the resin, a long-chain aliphatic polyol and a long chain are contained in the polyester resin. A toner for developing an electrostatic charge image, which comprises a structure obtained by reacting at least one selected from an aliphatic diol and a long-chain aliphatic monoalcohol. 2. The low molecular weight compound is a diol component and a polycarboxylic acid polycondensed with a dicarboxylic acid or its anhydride or its lower alkyl ester and a polycarboxylic acid, and has a number average molecular weight (Mn) of 3000 or less. The toner for developing an electrostatic charge image according to claim 1, characterized in that: 3. A low molecular weight compound contracts a diol component, a dicarboxylic acid or its anhydride or its lower alkyl ester, a phenolic hydroxyl group-containing carboxylic acid or its anhydride or its lower alkyl ester and a polyol or a polycarboxylic acid. The toner for developing an electrostatic charge image according to claim 1, wherein the polymerized number average molecular weight (Mn) is 3,000 or less. 4. A long-chain aliphatic polyol, a long-chain aliphatic diol or a long-chain aliphatic monoalcohol having 12 or more carbon atoms, and a long-chain aliphatic polyol, a long-chain aliphatic diol or a long-chain aliphatic monoalcohol. The toner for developing an electrostatic charge image according to claim 1, wherein the alcohol is used in an amount of 0.1 to 50 mol% with respect to the low molecular weight alcohol component.