JPS58198049A - Electrostatic image developing toner - Google Patents

Abstract

PURPOSE:To obtain the entitled toner superior in an electrostatical charge controllability, developing performance, transferability, fixability, offset resistance, and negative chargeability, by using a specified resin as a fixing resin. CONSTITUTION:The entitled toner is obtained by copolymerizing 98-50pts.wt. active vinyl monomer mixture consisting of 60-85wt% aromatic vinyl monomer and 40-15wt% alpha,beta-disubstituted aliphatic unsatd. dibasic diester type monomer in the presence of 2-50pts.wt. unsatd. polyester contg. 0.2-10wt% aliphatic unsatd. dibasic acid, and having 50-90 deg.C glass transition point measured by DTA method, 80-120 deg.C glass transition point measured by the ring and ball method, 5-60mg KOH acid value, and 500-10,000 average mol.wt. measured by the terminal group method to obtain a resin compsn. having 50-80 deg.C glass transition point, 110-170 deg.C softening point, and <=50,000mol.wt., and melting and kneading it together with a colorant using this resin as a fixation resin, and finally finely pulverizing them after cooling.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to toners used in electrophotographic development.

More specifically, the present invention relates to a dry electrostatic image developing toner that has excellent charge control during development and transfer, excellent fixing properties and anti-offset properties when fixing using a heated roll fixing method, and has good negative chargeability. .

Electrophotography uses a photoconductive layer containing an inorganic photoconductive material such as selenium, zinc oxide, cadmium sulfide, or an organic photoconductive material such as anthracene or polyvinylcarbazole in a binder resin as necessary. Alternatively, an electrostatic latent image is formed on a photosensitive plate, developed with a developer consisting of toner, transferred to paper, a sheet, etc., and then fixed using a solvent, heat, pressure, etc.

This developer consists of a mixture of a toner and a carrier, and the toner further contains a coloring agent such as carbon black, a charge control agent such as an azo dye, etc. dispersed in a natural or synthetic fixing resin.
It is made to contain.

In electrophotography, the triboelectricity of toner and carrier during development is important. That is, when the amount of charge on the toner is small, the electrostatic attraction between the toner and the carrier is weak, and therefore the toner is released from the carrier by a slight impact, resulting in staining of the background. On the other hand, if the amount of charge on the toner is too large, the toner will be separated from the carrier during development and become fins, which will not only require a strong electric field in the device but also worsen the edge effect. Therefore, in producing toner, it is necessary to control the amount of charge within a suitable range. In order to control the amount of charge on the toner, a method is generally adopted in which a small amount of a charge control agent mainly consisting of a dye is added to a mixture of a fixing resin and a colorant. It is difficult to uniformly disperse the toner, and the toner itself has the disadvantage of causing unevenness in the amount of charge.

Furthermore, in electrophotography, the toner image is fixed after development and transfer. Conventionally, the so-called oven fixing method, in which the transferred toner image is melted and fixed in an oven, has been mainstream. In recent years, from the viewpoints of downsizing, high-speed copying, and energy saving of copying machines, there has been a shift to a so-called heated roll fixing system in which fixing is performed using a heated roll.

In the conventional oven fixing method, a so-called oligomer resin having a molecular weight of 10,000 or less is used as a toner fixing resin because it needs to be melted quickly in an oven. However, in the heated roll fixing method, when such oligomers are used as the fixing resin, part of the toner adheres to the surface of the fixing roll during fixing and stains other adjacent papers or sheets, resulting in so-called offset. It is extremely impractical.

In order to prevent this offset, there is a method of applying a mold release liquid such as silicone oil to the fixing roll, but it is mechanically difficult to apply it uniformly, and the mold release liquid is heated, causing odor. There are many problems such as the occurrence of

In order to prevent offset in terms of the fixing resin, it is effective to increase the molecular weight of the resin, and in the case of polystyrene, which is commonly used as a resin, the average molecular weight is 50,000 or more, preferably 100,000 or more, which requires heating. No offset to roll at all. However, when such a high molecular weight resin is used as a fixing resin, there is a drawback that the toner's fixability to paper or sheets is extremely poor, and once the fixed image is It has the disadvantage that it peels off easily.

Therefore, a first object of the present invention is to provide a toner for developing electrostatic images that has excellent charge control properties and excellent developability and transferability.

A second object of the present invention is to provide a toner for developing electrostatic images with excellent fixing properties and offset properties, which solves the problems that occur in heated roll fixing systems.

In particular, in order to achieve the second objective, there are methods of adding oligomers with a molecular weight of about 1000 or less to high molecular weight polystyrene, methods of adding a mold release agent such as paraffin to a relatively low molecular weight polymer, and methods of adding a mold release agent such as paraffin to a relatively low molecular weight polymer. A method of adding a low molecular weight polyolefin having a molecular weight of about 10,000 or less to an acrylic polymer, a method of partially crosslinking with a bifunctional monomer, etc. have been proposed. However, the reality is that the first objective mentioned above has not been achieved at the same time.

The present inventors have conducted intensive research on a toner for developing electrostatic images (hereinafter referred to as the toner of the present invention) that is particularly suitable for the heating roll fixing method and satisfies the above conditions, and have found that it has negative charging characteristics as a fixing resin. In the presence of an excellent unsaturated polyester resin, an active vinyl monomer mixture containing an aromatic vinyl monomer and an α,β-disubstituted aliphatic unsaturated dibasic acid diester monomer as essential components is combined. The inventors have discovered that the resin composition obtained by polymerization exhibits excellent properties, and have completed the present invention.

That is, the resin composition of the present invention contains 0.2 to 10% by weight of an aliphatic unsaturated dibasic acid, has a glass transition point (hereinafter referred to as Tg) by DTA of 50 to 90°C, and a softening point by the ring and ball method. (hereinafter referred to as softening point) is 80-120℃, acid value is 5-60 ■KOH/g, average molecular weight by end group method (
In the presence of 2 to 50 parts by weight of an unsaturated polyester having an average molecular weight of 500 to 10,000,
parts by weight of an active vinyl monomer mixture, and in this monomer mixture, at least 50% by weight of an aromatic vinyl monomer and 2 to 5% by weight of α, β- It is characterized by containing a disubstituted aliphatic unsaturated dibasic acid diester monomer as an essential component.

The present invention will be explained in more detail below.

The unsaturated polyester which is the first component of the resin composition of the present invention contains aliphatic saturated dibasic acid and/or aromatic dibasic acid, aliphatic dihydric alcohol and/or alicyclic dihydric alcohol and/or aromatic Although it is obtained by a polycondensation reaction with a dihydric alcohol, it must contain 0.2 to 10% by weight of aliphatic unsaturated dibasic acid as an essential component.

Examples of the aliphatic unsaturated dibasic acid used in the present invention include maleic acid, fumaric acid, itaconic acid, citraconic acid, and acid anhydrides thereof, and maleic anhydride is industrially most preferred.

Other dibasic acids include aliphatic saturated dibasic acids such as succinic acid, glutaric acid, adipic acid, pimelic acid, speric acid, azelaic acid, sebacic acid, 1,11-undecanedicarboxylic acid, and 1,12-dodecanedicarboxylic acid. , phthalic acid and anhydride isophthalic acid, terephthalic acid, tetrachlorophthalic anhydride, tetrabromo phthalic anhydride, 3.3',
Aromatic dibasic acids such as 4.4'-benzophenone tetracarboxylic anhydride are mentioned. Examples of dihydric alcohols include ethylene glycol propylene glycol, diethylene glycol, diprobi-6-lengelicol, 1,3-butanediol, ]-, ]4
-Butanediol 1,5-bentanediol, ■, 6-
Hexanediol, neopentyl glycol, 3,3.
Aliphatic dihydric alcohols such as 5-trimethyl-2,4-bentanediol, 114-cyclohexane dimetatool, alicyclic dihydric alcohols such as hydrogenated bisphenol A, bisphenol A ethylene oxide adduct (think bisphenol AEO adduct) ), bisphenol A
Propylene oxide adduct (hereinafter referred to as bisphenol APO)
aromatic dihydric alcohols such as (referred to as adducts).

In addition to these components, trifunctional compounds such as trimellitic anhydride, glycerin, trimethylolethane, and trimethylolpropane, and monofunctional compounds such as benzoic acid, p-tert-butylbenzoic acid, cyclohexanol, and 2-ethylhexanol are also used. Compounds can also be used as appropriate to adjust the molecular weight.

The aliphatic unsaturated dibasic acid in the second component is an important component in the sense that it becomes an active site during copolymerization, and its content is 0.
2-10% by weight is suitable.

When the content of the aliphatic unsaturated dibasic acid is less than 0.2% by weight, copolymerization is difficult to occur, and when it is more than 10% by weight, it becomes gelatinous during polymerization and is not practical. The preferred content varies depending on the molecular weight of the unsaturated polyester, but the optimum content is 0.5 to 7% by weight.

The Tg and softening point of unsaturated polyester are 50 to 90°C, respectively.
and 80 to 120° C., and if the above value is lower or higher than that, it will have an adverse effect on the fixability and crushability of the toner, although it will vary depending on the amount of unsaturated polyester used.

The acid value of unsaturated polyester is 5-60W @KOI-1/
g is suitable, but when the acid value is 5 KOH/g or less and 6
In the case of 0 KOH/g or more, the amount of charge becomes insufficient or excessive, depending on the amount of unsaturated polyester used, which adversely affects the developability and transferability. The preferred acid value is optimally 10 to 50 Akebono KOH/g.

The molecular weight of the unsaturated polyester is preferably 500 to 10,000, but if the molecular weight exceeds 10,000 and becomes too large, gelation tends to occur during polymerization, making it difficult to obtain a suitable resin composition. The preferred molecular weight varies depending on the amount of unsaturated polyester used, but 1500 to 5000 is optimal.

The above unsaturated polyester is produced by a conventional method while introducing an inert gas at an excess of 0 to 50%.
The desired unsaturated polyester can be obtained by carrying out the reaction at a temperature of 50° C. and monitoring the reaction by measuring the acid value, hydroxyl value, and softening point. Further, the acid anhydride may be added for the purpose of adjusting the acid value.

A resin composition is obtained by copolymerizing an active vinyl monomer mixture in the presence of the unsaturated polyester thus obtained.

The monomer mixture includes, as essential components, aromatic vinyl monomers such as styrene, α-methylstyrene, and 0-chlorostyrene, dimethyl maleate, diethyl maleate, dibutyl maleate, and di-2-maleate. Examples include α,β-disubstituted aliphatic unsaturated dibasic acid diester monomers such as ethylhexyl, dimethyl fumarate, diethyl fumarate, diptyl fumarate, di-2-ethylhexyl fumarate, and other vinyl-based Monomers include methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, 2-ethylhexyl methacrylate, acrylic acid , methacrylic acid, maleic acid, fumaric acid, itaconic acid and the like.

The above monomers may include at least 50% by weight of an aromatic vinyl monomer and 2 to 50% by weight of an α,β-disubstituted aliphatic unsaturated dibasic acid diester monomer as essential components. 91 According to a preferred embodiment of the present invention, the monomer contains 60 to 85% by weight of styrene as an aromatic vinyl monomer.
, most suitable when the α,β-disubstituted aliphatic unsaturated dibasic acid diester monomer is 40 to 15% by weight of diptyl fumarate, and the other monomer is 2-ethylhexyl acrylate 0 to 25% by weight. A fixing resin can be obtained.

To copolymerize the above monomer in the presence of the unsaturated polyester, 98 to 50 parts by weight, preferably 98 to 50 parts by weight of the monomer is added to 2 to 50 parts by weight, preferably 5 to 40 parts by weight, of the unsaturated polyester. It is optimal to use 95 to 60 parts by weight.

Polymerization reaction methods for copolymerizing monomers in the presence of unsaturated polyester include solution polymerization, suspension polymerization, and emulsion polymerization, but suspension polymerization is optimal from an industrial standpoint.

The suspension polymerization reaction can be carried out by combining the unsaturated polyester and the monomer in water in the presence of a polymerization initiator and a dispersant at a temperature of 60 to 90° C. according to a conventional method.

The molecular weight of the resin composition which is the fixing resin used to obtain the toner of the present invention is 50,000 or less, preferably 5,000 to 30,000.
It is 000.

When producing the resin composition by suspension polymerization, examples of the polymerization initiator include 2,2'-azobisisobutyronilyl, 10-benzoyl peroxide, benzyl peroxide, and t-butylperoxy-2-ethylhexane. Noate etc. can be used alone or in combination. Further, as the dispersant, polyvinyl alcohol, polyvinylpyrrolidone, methyl cellulose, hydroxyethyl cellulose, polyacrylic acid, polymethacrylic acid, magnesium carbonate, lime triphosphate, calcium phosphate, etc., which are used in ordinary suspension polymerization, can be used.

The obtained resin composition according to the present invention has a Tg of about 50 to 80.
C., and a softening point of about 110 to 170.degree. C. is particularly suitable as a fixing resin.

That is, when the tg is about 50°C or less, the fixing performance is excellent, but the toner often clumps due to the cold flow phenomenon, and when the tg is about 80°C or more, the fixing is insufficient, especially during high-speed copying. Become.

On the other hand, if the softening point is about 110°C or lower, contamination of the photoconductive layer or photosensitive plate is likely to occur due to toner filming phenomenon, and if the softening point is about 170°C or higher, it becomes difficult to crush when forming toner. Furthermore, it requires a large amount of heat during fixing, which is not practical.

In addition, the resin composition according to the present invention can improve the composition of fine resin powder (average particle size of about IOμ to 20μ) by blow-off method with iron powder (average particle size of about 500μ) by changing the amount of unsaturated polyester used. The amount of triboelectric charge is about -10μc/g~-
It can be adjusted arbitrarily within the range of 40 μC/g, and appropriate charging characteristics can be obtained when designing a copying machine without using a charge control agent such as a dye used in conventional toners. It is something.

The toner of the present invention can be obtained by using the resin composition according to the present invention as a fixing resin, melting and kneading a colorant by a conventional method, cooling it, and then pulverizing it with a hammer mill, jet mill, etc.

When the above-mentioned resin composition is used as a fixing resin in the toner of the present invention, it has excellent developability and transferability, and also has low-temperature fixability when fixing by a heated roll fixing method and so-called offset resistance that is difficult to offset. The traditional problems of pottery can be solved all at once.

It is not clear why the toner of the present invention is effective in both low-temperature fixing properties and offset resistance, but gel
When the molecular weight distribution of the resin composition of the present invention was measured by vermation chromatography (hereinafter referred to as GPC), the molecular weight distribution of only the monomer without using the unsaturated polyester was approximately 2 to 4 in terms of 'jiv/Mn. However, by copolymerizing an active vinyl monomer mixture in the presence of an unsaturated polyester, a low molecular weight portion (Mw/Mn) that has a large Mw/Mn of about 5 to 20 and contributes to low-temperature fixing properties (
This is thought to be due to the fact that the resin composition of the present invention contains both a high molecular weight part (molecular weight of about 5 million) that contributes to anti-offset properties.

Further, the α,β-disubstituted aliphatic unsaturated dibasic acid diester monomer in the monomer is an essential component of the resin composition of the present invention, and the monomer excluding this monomer is When the monomer is copolymerized in the presence of the unsaturated polyester, it is difficult to control the molecular weight, Tg, and softening point of the resin composition compared to the case of the resin composition of the present invention using the present monomer. And also,
The resulting resin composition has very poor pulverization properties when it is turned into a toner.

The reason why the present monomer is so effective is thought to be due to its polymerizability and property of softening the resin without reducing its crushability.

Colorants that can be used in the toner of the present invention include black pigments such as carbon black, acetylene black, lamp black, and aniline black, yellow pigments such as chrome yellow, zinc yellow, yellow iron oxide, nickel titanium yellow, benzidine yellow GR, and molybdenum. Orange pigments such as orange, permanent orange GTR, benzidine orange G1 indanthrene brilliant orange GK, red pigments such as red red pigment, permanent red 4R, watching red, calcium salts, lake red, alizarin lake, brilliant carmine 3B,
Violet pigments such as Manganese Purple, Fast No 1 Quiolette B1 Methyl Violet Lake, Blue pigments such as Navy Blue, Cobalt Blue, Victoria Blue Lake, Phthalocyanine Blue, Fast Sky Blue, Indan Stremburu-BC, Pigment Green B1 Malachite Green Lake, Fa Examples include green pigments such as Naru Yellow Green G, white pigments such as zinc white, titanium oxide, antimony white, and zinc sulfide, and various dyes such as nigrosine, methylene blue, rose bengal, giraffe yellow, and ultraman blue.

Furthermore, for the purpose of imparting fluidity and releasability to the toner of the present invention, known ones among low molecular weight olefin polymers, fatty acids, and fatty acid metal salts may be added at any stage of manufacturing the toner of the present invention. Also good.

As a low molecular weight olefin polymer, the molecular weight is about 100.
0 to 10,000 is preferable, and examples thereof include polyethylene, polypropylene polymers, ethylene-propylene copolymers, and the like. Examples of fatty acids and fatty acid metal salts include fatty acids having 12 to 18 carbon atoms, such as lauric acid, myristic acid, palmitic acid, stearic acid, seamaric acid, oleic acid, linoleic acid, and lilunic acid, and their calcium, barium, sodium, lithium, and magnesium. , manganese-14-zinc, nickel, cobalt, iron, lead salts, etc.

Further, the toner of the present invention is effective not only as a toner for a two-component developer but also as a toner for a -component developer by using a magnetic material. The magnetic material can be added at any stage of manufacturing the toner of the present invention, and includes, for example, iron sesquioxide, triiron tetroxide, nickel sesquioxide, and other oxides, fine or ultrafine iron particles as metal powder, Examples of magnetic materials include fine metal powders such as cobalt, copper, silver, gold, aluminum, and tin.

In addition, the particle size of the toner for the -component developer is 1 to 40.
μ, preferably 10 to 20 μ is suitable.

The present invention will be explained in more detail with reference to Examples below, but the present invention is not limited by these Examples.

In addition, "parts" shown in the following examples and comparative examples indicate "parts by weight" unless otherwise specified.

(Example-1) Isophthalic acid 1 was placed in a 10A four-eye flask equipped with a stirrer, condenser, inert gas introduction tube, and temperature needle.
660 parts of maleic anhydride, 25.5 parts of maleic anhydride, 3878 parts of bisphenol APO 2 mole adduct, and 27.8 parts of diptyltin oxide were reacted at 220°C in a nitrogen stream for about 10 hours to reduce the maleic acid content to 0.5 parts by weight. %, acid value 10
■KOII/g, hydroxyl value 15■Roll/g, average molecular weight approximately 4500, 7g 70℃ by DT8 and softening point 1
A 00'C unsaturated polyester (hereinafter referred to as polyester) was obtained. This polyester is finely pulverized and the average particle size is 1
Although the charge was set at 2μ, the amount of charge determined by the blow-off method was -32μ.
c/g.

A polymerizable solution was prepared by dissolving 200 parts of this polyester in 225 parts of styrene and 75 parts of diptyl fumarate.

In a polymerization reaction vessel with a capacity of 21 equipped with a stirrer, a condenser, a nitrogen gas blowing tube, and a thermometer, 1000 parts of water and polyvinyl alcohol (Poval 217 manufactured by Kuraray) were added.
5 After charging aLi and raising the temperature to 70°C while stirring at 150 rpm, the inside of the system was flushed with nitrogen gas, and 500 parts of polymerizable i-liquid containing 40% by weight of the above polyester and 2.2'
- 5.0 parts of azobisisobutyronitrile was added dropwise over 1 hour. After reaction at 70°C for 1 hour, the temperature was raised to 80°C in 30 minutes, and the polymerization was completed in 10 hours.

After the polymerization is completed, the suspension is cooled, filtered, and taken out. The dispersant is washed away with water, and after drying, a bead-shaped resin composition (12+
(referred to as lower resin) was obtained.

The number average molecular weight (hereinafter referred to as number average molecular weight) of this resin by GPC is 7800, the Tg is 67°C, and the softening point is 15.
At 5℃! there were.

90 parts of this resin and 10 parts of carbon blank (Morgan A manufactured by Cabosoto) were melt-kneaded at 180°C, cooled, and coarsely pulverized to several hundred microns in a thermometer mill, then finely pulverized in a jet mill to have an average particle size of 12 microns. Toner (A) was obtained.

(Example-2) Maleic acid-containing polyester was produced using the same method as the method for producing polyester of Example-1 from 1,660 parts of isophthalic acid, 57 parts of maleic anhydride, 4,190 parts of bisphenol APO 2 molar adduct, and 29.5 parts of diptyltin oxide. Quantitative 1.0% by weight, acid value 15 ■KOH/g, hydroxyl value 36 ■KOH/g
, average molecular weight about 2200.7g 73℃ and softening point 115
℃ polyester was obtained. This fine powder of polyester (
The charge amount of 12μc/g was -24μc/g.

From a polymerizable solution consisting of 100 parts of this polyester, 220 parts of styrene, and 180 parts of di-2-ethylhexyl fumarate, and 3.75 parts of AiBN, a number average molecular weight of 8500, 7 g, 65°C, and a softening point of 15 was prepared in the same manner as in Example-1.
A resin at 0°C was obtained.

90 parts of this resin and 10 parts of carbon black (Morgan A)
The mixture was melt-kneaded at 180° C., cooled, and then finely pulverized to obtain a toner (B) having an average particle size of 12 μm.

(Example-3) 50 parts of polyester obtained in Example-2, 296 parts of styrene
17 parts, 115.5 parts of dibutyl fumarate, and 2 parts of acrylic acid.
- A polymerizable solution consisting of 38.5 parts of ethylhexyl and 6.25 parts of 2.2'-azobisisobutyronitrile was prepared in the same manner as in Example 1 to obtain a number average molecular weight of 14,600.
7g of resin was obtained at 56°C and a softening point of 130°C.

90 parts of this 41n and carbon black (Morgan A)
10 parts were melt-kneaded at 170° C., cooled, and then finely pulverized to obtain a toner (C) having an average particle size of 12 μm.

(Example-4) Terephthalic acid 16 was placed in a 51-volume four-eye flask equipped with a stirrer, condenser, inert gas introduction tube, and temperature needle.
60 parts, 2,2-dimethyl 1,3-propanediol 1
368 parts and 16 parts of dibutyltin oxide were charged, and the temperature was raised from 150°C to 240°C over 6 hours in a nitrogen stream.
The reaction was further carried out at 240°C for 6 hours, the temperature was lowered to 11180°C, 203 parts of maleic anhydride was added and the reaction was carried out at 180°C for 2 hours, resulting in a maleic acid content of about 7% by weight and an acid value of 11■KO.
H/g, hydroxyl value 45 KOH/g, average molecular weight approximately 20
00.7g of polyester having a softening point of 95°C was obtained at 65°C. The amount of charge of this polyester fine powder (12μ) is -11
It was 6μc/g.

From a polymerizable solution consisting of 25 parts of this polyester, 295 parts of styrene, and 180 parts of diptyl fumarate, and 5.0 parts of 2,2'-azo 18-bisisobutyronitrile, a number average solution was prepared in the same manner as in Example 1. A resin having a molecular weight of 17,600.7 g, 59° C., and a softening point of 125° C. was obtained.

90 parts of this resin and carbon black (Mitsubishi Kasei MA-
8) and 10 parts were melt-kneaded at 170° C., cooled, and then finely pulverized to obtain a toner (D) having an average particle size of 12 μm.

(Example-5) 75 parts of polyester obtained in Example-1, 276 parts of styrene
and 149 parts of diptyl fumarate and 2.5 parts of 2,2'-azobisisobutyronitrile,
t-Butylperoxy 2-ethylhexanoate 3.3
part, number average molecular weight 105 in the same manner as in Example-1.
00.7g of resin was obtained at 58°C and a softening point of 152°C.

92 parts of this resin and 8 parts of carbon black (MA-3) were melt-kneaded at 180'C, cooled, and then finely pulverized to obtain a toner (E) having an average particle size of 12 .mu.m.

(Example-6) 1,000 parts of the polyester obtained in Example-2 and 83 parts of phthalic anhydride were charged into a four-eye flask with a volume of 2β equipped with a stirrer, a condenser, an inert gas introduction tube, and a temperature needle, and the mixture was heated with a nitrogen stream. Raise the temperature to 160'C over 1 hour,
React at 160°C for an additional 3 hours to reduce maleic acid content to 0.
．． 9% by weight, acid value 44 ■KOH/g, hydroxyl value 8 ■KO
A polyester having an average molecular weight of about 2300.7863°C and a softening point of 100°C was obtained. The amount of charge of the fine powder (12μ) of this polyester was -24μc/g. 2.2'-
A resin having a number average molecular weight of 12,000, a Tg of 60°C and a softening point of 153°C was obtained using 2.5 parts of azobisisobutyronitrile and the same method as in Example-1.

45 parts of this resin and carbon black (Mitsubishi Kasei #44)
) 5 parts and triiron tetroxide (Toda Kogyo magnetite) E
PT-500) were melt-kneaded at 180° C., cooled, and then finely pulverized to obtain a one-component toner (F) having an average particle size of 13 μm.

(Comparative Example-1) In Example-1, a number average molecule was obtained in the same manner as in Example-1 without using polyester! 30700.7g7
A comparative styrene-dibutyl fumarate copolymer resin having a softening point of 6°C and a softening point of 134°C was obtained. 90 parts of this resin and 10 parts of carbon black (Morgan A) were melt-kneaded at 160°C, cooled, and then finely pulverized to form a comparative toner (A) with an average particle size of 12μ.
I got it.

(Comparative Example-2) 50 parts of polyester obtained in Example-2, 382 parts of styrene
, 5 parts and 67.5 parts of 2-ethylhexyl acrylate, and 6.25 parts of 2,2'-azobisisobutyronitrile, a number average molecular weight of 15,500, Tg 6,000℃ and softening point 152℃
A comparative resin was obtained.

90 parts of this resin and 10 parts of carbon black (Morgan A
) were melt-kneaded at 180°C, cooled, and then finely pulverized.
(b) was obtained.

(Comparative Example-3) In the polyester of Example-1, only maleic anhydride was used as the dibasic acid, and a polyester obtained from 11,980 parts of maleic anhydride rI, 3,780 parts of bisphenol APO 2 mol adduct, and 23.8 parts of dibutyltin oxide ( Maleic acid content approximately 22% by weight, acid value 13.5 ■KOH/
g, hydroxyl value 22 ■KOH/g, average molecular weight approximately 3200
．． A resin was obtained in the same manner as in Example 2, except that 7g (65°C, softening point: 115°C) was used.

This resin is insoluble in TIIF for GPC measurement, which indicates that the resin has a crosslinked structure.Also, we tried to produce a two-component comparison toner (c) by adding carbon black, but 21- Even on a roll at 220°C, it did not melt and could not be kneaded.

(Comparative Example-4) 300 parts of polyester obtained in Example-1, 12 parts of styrene
From a polymerizable solution consisting of 0 parts and 80 parts of diptyl fumarate and 2.5 parts of 2.2'-azobisisobutyronitrile, a number average molecular weight of about 5400 was prepared in the same manner as in Example-1.
．． 7 g of a comparative resin having a softening point of 162° C. and a softening point of 60° C. was obtained.

90 parts of this resin and 10 parts of carbon black (MA-8) were melt-kneaded at 190°C, cooled, and then finely pulverized to have an average particle size of 1.
A comparative toner (d) of 2μ was obtained.

(Comparative Example-5) From 1660 parts of isophthalic acid, 52 parts of maleic anhydride, 3626.5 parts of bisphenol A 802 molar adduct and 26.7 parts of dibutyltin oxide, a method similar to the method for producing polyester of Example-1 was used. Maleic acid content pledge 1.
1% by weight, acid value 15 ■KOH/g, hydroxyl value 22 ■KO
A comparative polyester was obtained having an average molecular weight of about 3000.7 g at 95°C and a softening point of 125°C. The amount of charge of this polyester fine powder (12μ) is -20μc/g
Met.

A polymerizable solution consisting of 50 parts of this comparative polyester, 275 parts of styrene, 107.5 parts of diptyl fumarate, and 67.5 parts of di-2-ethyl 22-hexyl fumarate and 2.2'-
A comparative resin having a number average molecular weight of 15 soo, g, 7g, 58°C and a softening point of 172°C was obtained from 5 parts of azobisisobutyronitrile in the same manner as in Example-1.

90 parts of this resin and 10 parts of carbon black (MA-8) were melt-kneaded at 190°C, cooled, and then finely pulverized to have an average particle size of 1.
A comparative toner (e) of 3μ was obtained.

(Comparative Example-6) Maleic acid was prepared from 1,660 parts of isophthalic acid, 66 parts of maleic anhydride, 5,186 parts of bisphenol APO 2 molar adduct, and 34.6 parts of dibutyltin oxide in the same manner as the polyester manufacturing method of Example-1. Contains 1.0% by weight, acid value 8 ■KOH/g, hydroxyl value 66 ■KOH/g
, a polyester having an average molecular weight of about 1500 was obtained. Further, 196 parts of phthalic anhydride was added to 1000 parts of this polyester in the same manner as in Example-6, resulting in a maleic acid content of 0.
．． 8% by weight, acid value 70 KOII/g, hydroxyl group measurement 4.
5■KOH/g, average molecular weight approximately 1600.7g 52℃,
A comparative polyester having a softening point of 86°C was obtained. The chargeability of this Boester fine powder (12μ) was 22μc/g.

2. A polymerizable solution consisting of 50 parts of this comparative polyester, 305 parts of styrene, and 145 parts of dibutyl fumarate;
Number average molecular weight 20800, 7g57 from 3.75 parts of 2-azobisisobutyronitrile in the same manner as in Example-1
A comparative resin with a softening point of 146° C. and a softening point of 146° C. was obtained.

90 parts of this resin and carbon black (M^-8) 1
0 parts were melt-kneaded at 170° C., cooled, and then finely pulverized to obtain a comparative toner having an average particle size of 12 μm.

(Comparative Example-7) 1,660 parts of isophthalic acid, 444.5 parts of maleic anhydride, 4,846 parts of bisphenol APO 2 mol adduct, 93 parts of propylene glycol, and 35 parts of diptyltin oxide.
The second part was reacted in a nitrogen stream at 220°C for about 10 hours in the same manner as the polyester manufacturing method of Example-1, and then further reacted at 220°C for about 6 hours under 1wHg reduced pressure to form a maleic acid-containing compound 6. .7% by weight, acid value 5■KOH/g,
Hydroxyl value: 4 ■KOII/g - average molecular weight: approximately 12,500.
7 g of a comparative polyester having a softening point of 120° C. and a softening point of 76° C. was obtained. The charge amount of this Boester fine powder (13μ) was -25μc/g.

A polymerizable solution consisting of 100 parts of this comparative polyester, 280 parts of styrene, and 120 parts of dibutyl fumarate;
゜2'-Example from 5 parts of azobisisobutyronitrile-
In the same manner as in Example 1, a comparative resin was obtained which was partially insoluble in THF but had a number average molecular weight of 29,800.7 g at 58°C and a softening point of 173°C.

45 parts of this resin, 5 parts of carbon black (#44), and 50 parts of triiron tetroxide were melt-kneaded at 200°C, cooled, and then finely ground to form a one-component comparison toner (T) with an average particle size of 16 μm.
I got it.

Test Method Various characteristics of the toners obtained in the above-mentioned Examples and Comparative Examples other than Comparative Example-3 were evaluated by the following methods.

(Frictional electrification amount) Except for the one-component toners of Example-6 and Comparative Example-7, the amount of electrification with an iron powder carrier (DSP128B manufactured by Dowa Iron Powder Industries) was measured by a blow-off method. In the case of the above-mentioned component-based toner, measurements were made in the same manner except for magnetite.

(Fixing properties, offset properties) Copy paper and toner °- (thickness 0.5 to 1
．． 0 dragon) silicone rubber (Shin-Etsu Chemical ml KE-130O
RTV”) or Teflon rubber (DuPont PGP)
Stack them one after another and place a 100g weight on top. After the heat plate was held at 170° C. for 5 minutes, the toner was examined for fixing to copy paper (cellophane tape removability) and toner offset to silicone rubber or Teflon rubber.

Regarding the fixing property, the toner was evaluated as ◯ if 90% or more of the toner was not removed from the copy paper by the cellophane tape, × if the toner was removed by 50% or more, and Δ if the toner was removed by 50 to 90%. Regarding offset properties, a state in which the toner was not fused to the silicone rubber or Teflon rubber was rated as ○, a state in which the toner was fused to the entire surface was rated as ×, and a state in which some fusion was observed was rated as Δ.

(Developability, transferability) An image was formed on a zinc oxide photosensitive plate, transfer paper was placed on top of the image, and a corona AC voltage was applied using a corotron to transfer the image to the transfer paper.

Depending on the capri condition of the image obtained at that time, an image with no fog was evaluated as 0, an image with fog on the entire surface was evaluated as ×, and an image with fog on some parts was evaluated as Δ.

(Image density) Measured with a reflection density needle after fixing. An image density of 1.20 or higher was judged to be good.

(Crushability) Yield (%) of particle size 5 to 15μ by pulverization during toner production
) was measured. A crushability of 70% or more was judged to be good.

(Blocking property) After the toner was left in a constant temperature and humidity bath at 60° C. and 60% R11 (relative humidity) for one week, a state in which the toner did not block was judged as ◯, and a state in which blocking was observed was judged as ×.

Tables 1 and 2 show the results of various toner properties obtained by the above test method.

26- From Tables 1 and 2, Examples-1 to toner of the present invention
Example-6 exhibited good developability, transferability, fixing properties, anti-offset properties, pulverization properties, and anti-blocking properties, and had toner properties that could not be obtained in Comparative Examples-1 to Comparative Examples-7. I can see that you are doing it.

That is, what gives such good toner properties is the presence of a specific polyester containing 0.2 to 10% by weight of aliphatic unsaturated dibasic acid, and the presence of an aromatic vinyl monomer as an essential component. and at least 50% by weight of α,β-disubstituted aliphatic unsaturated dibasic acid diester monomers.
This is achieved by using a resin composition obtained by copolymerizing an active vinyl monomer mixture containing 0% by weight as a fixing resin.

27-

Claims (1)

[Claims] 1. Aliphatic unsaturated dibasic acid of 0.2 to 0.2 to
Contains 10% by weight, has a glass transition point of 50 to 90°C, a softening point of 80 to 120°C by ring and ball method, and an acid value of 5 to 60.
KOH/g, average molecular weight by end group method is 500-10
1. A toner for electrostatic image development used in a heated roll fixing system, characterized by using a resin composition obtained by copolymerizing a monomer in the presence of a 0.000 unsaturated polyester. 2. The toner according to claim 1, wherein the amount of unsaturated polyester is 2 to 50 parts by weight and the amount of monomer is 98 to 50 parts by weight. 3. The monomers must be at least 50% by weight of an aromatic vinyl monomer and 2 to 50% by weight of an α,β-disubstituted aliphatic unsaturated dibasic acid diester monomer as essential components. The toner according to claim 1, characterized in that: 4. The toner according to claim 1, wherein the resin composition is negatively chargeable.