JPH06110250A - Toner binder and toner composition - Google Patents

Abstract

PURPOSE:To provide a polyester binder for an electrophotographic toner excellent in fixability at low temp. and plasticizer migration resistance. CONSTITUTION:A polyester binder for a toner and an electrophotographic toner compsn. using the binder are provided. The binder is made of polyester resin consisting of a polycarboxylic acid component and a polyol component as constituent units and at least part of the polyol component is an alkylene oxide deriv. of a heterocyclic compd. having two or more active hydrogen atoms in each molecule such as an isocyanuric acid-alkylene oxide adduct.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an electrophotographic toner binder and an electrophotographic toner composition comprising the binder.

[0002]

2. Description of the Related Art In electrophotography, an electrostatic latent image is formed on a photoconductor by a conventional method, developed with a dry toner, the toner image is transferred onto a copy sheet, and then heat fixing (usually with a heat roller is performed). Use) and got a copy. Heretofore, polystyrene resins, styrene-acrylic copolymers, polyester resins, epoxy resins and the like have been generally used as toner binders that are components of this dry toner, among which polystyrene resins, polystyrene-based resins such as styrene-acrylic copolymers. It is widely used from the viewpoints of performance such as thermoplasticity, pulverizability, and chargeability and low cost. However, with the recent increase in the processing speed of copiers and the widespread use of color copiers and printers, there has been a strong demand for polyester resins that are superior in low-temperature fixability to conventional styrene resins. Conventionally, as a typical example of this type of polyester resin for toner binder, US Pat.
Polyhydric alcohols having a valency of 3 or more in the specification of No. 1,106 (trimethylolpropane, pentaerythritol, etc.)
A polyester resin (1) using the alkylene oxide adduct of (1) has been proposed. Also, US Pat.
No. 7,211 and US Pat. No. 4,657,837 propose a polyester resin (2) using trimellitic acid.

[0003]

However, although the polyester resins (1) and (2) are superior in low-temperature fixability to conventional styrenic resins, the low-temperature fixability can be improved by, for example, reducing the molecular weight of polyester. If it is attempted, the plasticizer migration resistance deteriorates, and it is difficult to achieve both low-temperature fixability and plasticizer migration resistance. The present invention has been made under the background described above, and its object is to provide a polyester electrophotographic toner binder and an electronic material which are made of a novel polyester resin excellent in both low temperature fixing property and plasticizer migration resistance. It is to provide a photographic toner composition.

[0004]

Means for Solving the Problems The inventors of the present invention have conducted extensive studies to achieve the above object, and as a result, by using a polyester resin having a heterocyclic structure in the molecule as a binder, low-temperature fixing property and plasticity resistance of a toner can be obtained. The present invention has been achieved by finding that both agent transferability is compatible. That is, according to the present invention, in a toner binder comprising a polyester resin having a polycarboxylic acid component (A) and a polyol component (B) as constitutional units, at least a part of (B) has two or more active hydrogens in the molecule. An electrophotographic toner composition comprising an electrophotographic polyester toner binder and the above polyester toner binder, which is a heterocyclic compound oxyalkylene ether (B1).

In the present invention, the polycarboxylic acid component (A)
Consists of divalent carboxylic acids (A1) and, if necessary, trivalent or higher carboxylic acids (A2). Specific examples of the divalent carboxylic acids (A1) include (1) maleic acid, fumaric acid, succinic acid, adipic acid, sebacic acid, malonic acid,
Aliphatic dicarboxylic acids having 2 to 20 carbon atoms such as azelaic acid, mesaconic acid, citraconic acid and glutaconic acid; (2) Cyclohexanedicarboxylic acid, alicyclic dicarboxylic acids having 8 to 20 carbon atoms such as methylmedic acid; (3) Aromatic dicarboxylic acids having 8 to 20 carbon atoms such as phthalic acid, isophthalic acid, terephthalic acid, toluene dicarboxylic acid, naphthalene dicarboxylic acid; (4) carbon number in the side chain of isododecenyl succinic acid, n-dodecenyl succinic acid, etc. Examples thereof include alkyl or alkenyl succinic acids having a hydrocarbon group of 4 to 35; and anhydrides and lower alkyl (methyl, butyl, etc.) esters of these divalent carboxylic acids. Among these, the above (1), (3), (4) and anhydrides or lower alkyl esters of these dicarboxylic acids are preferable, and maleic acid, fumaric acid, isophthalic acid, terephthalic acid, dimethyl terephthalate, n- Dodecenyl (anhydrous) succinic acid is more preferred. (Anhydrous) maleic acid and fumaric acid are preferable because they have high reactivity, and isophthalic acid and terephthalic acid are preferable because they increase the glass transition temperature of the polyester. Alkyl or alkenyl (anhydrous) succinic acid has the advantage of improving the pigment dispersibility of the toner.

Specific examples of tricarboxylic or higher polycarboxylic acids (A2) include (1) 1,2,4-butanetricarboxylic acid, 1,
2,5-hexanetricarboxylic acid, 1,3-dicarboxylic-2-
Aliphatic polycarboxylic acids having 7 to 20 carbon atoms such as methyl-2-methylenecarboxypropane, tetra (methylenecarboxylic) methane, and 1,2,7,8-octanetetracarboxylic acid;
(2) Number of carbon atoms in 1,2,4-cyclohexanetricarboxylic acid
9-20 alicyclic polycarboxylic acids; (3) 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, 2,5,
Aromatic polycarboxylic acids having 9 to 20 carbon atoms such as 7-naphthalene tricarboxylic acid and 1,2,4-naphthalene tricarboxylic acid, pyromellitic acid and benzophenone tetracarboxylic acid;
In addition, their anhydrides and lower alkyl (methyl, butyl, etc.) esters can be mentioned. When (A2) is used, among these, (3) and its anhydrides and lower alkyl esters are preferable, and particularly 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid and their anhydrides. And lower alkyl ester are preferable from the viewpoints of price and imparting offset resistance of the toner. The proportion of (A2) used in (A) is usually 0 to 30 mol%, preferably 0 to 20 mol%, and more preferably 0 to 10 mol%.

In the present invention, the polyol component (B)
Is an oxyalkylene ether (B1) which is a heterocyclic compound having two or more active hydrogens in the molecule, optionally other dihydric alcohols (B2) and optionally other trihydric or higher alcohols ( B3).

The oxyalkylene ether (B1), which is a heterocyclic compound having two or more active hydrogens in the molecule, is the same as the heterocyclic compound (a) having two or more active hydrogens in the molecule. Compound (b) having one epoxy ring
It is a reaction product with.

Examples of the heterocyclic compound (a) having two or more active hydrogens in the molecule include aminopyridine, diaminopyridine, triaminopyridine, isocyanuric acid, melamine, acetoguanamine, benzoguanamine,
Examples thereof include 3-amino-1,2,4-triazole and methylol compounds thereof. Among these, a heterocyclic compound having 3 or more active hydrogens in the molecule is preferable, diaminopyridine, isocyanuric acid and melamine are more preferable, and isocyanuric acid is most preferable.

Specific examples of (b) include ethylene oxide (EO), 1,2-propylene oxide (PO) and 1,2-
Examples thereof include butylene oxide, 2,3-butylene oxide, styrene oxide and epichlorohydrin. Also, as (b), an aliphatic monohydric alcohol having 1 to 20 carbon atoms or glycidyl ether of monohydric phenol can be used. Of these, EO and / or PO are preferred. The number of moles of (b) added to 1 mole of (a) constituting (B1) is usually 2 to 10 moles, preferably 3 to 10 moles.
It is a mole.

As an example of the production method of (B1), (B1) is obtained by adding (b) to (a) in the presence of a catalyst (basic catalyst or acidic catalyst), if necessary. The reaction temperature is usually 20 to 250 ° C., preferably 70 to 200 ° C., and usually the reaction is carried out under pressure. The reaction can also be carried out in the presence of a solvent (for example, xylene, dimethylformamide, etc.) or other dihydric alcohols (B2) and / or other trihydric or higher alcohols (B3).

Other dihydric alcohols (B2) include
For example, (1) ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanedio-
Le, neopentyl glycol, 1,4-butenediol, 1,
Carbon number of 5-pentanediol, 1,6-hexanediol, etc.
2 to 12 alkylene glycols; (2) alkylene ether glycols such as diethylene glycol, triethylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol; (3) 1,4-cyclohexanedimethanol, An alicyclic diol having 6 to 30 carbon atoms such as hydrogenated bisphenol A; and (4) bisphenols such as bisphenol A, bisphenol F, and bisphenol S; and (5) alkylene oxides (EO, PO, Butylene oxide, etc.) 2 to 8 mol adduct. When using (B2),
Among these, (1) and (5) are preferable, and (5) is more preferable. Among the above (1), ethylene glycol increases the reaction rate, and 1,2-propylene glycol and neopentyl glycol are preferable from the viewpoint of low temperature fixability. In addition, among the above (5), particularly EO of bisphenol A
And / or PO2-4 mol adducts are preferred in that they provide good offset resistance to the toner.

Specific examples of other trihydric or higher alcohols (B3) include (1) sorbitol, 1,2,3,6-hexanetetraol, 1,4-sorbitan, pentaerythritol, dipentaerythritol, Tripentaerythritol, 1,2,4-butanetriol, 1,2,5-pentanetriol, glycerol, 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, trimethylolpropane Such as aliphatic polyhydric alcohols having 3 to 20 carbon atoms; (2) aromatic polyhydric alcohols having 6 to 20 carbon atoms such as 1,3,5-trihydroxylmethylbenzene; and alkylene oxide adducts thereof. be able to. When (B3) is used, the compound of (1) is preferable among them, and among them, glycerol, trimethylolpropane and pentaerythritol are preferable from the viewpoint of being inexpensive. (B1), (B2) in (B),
The composition ratio (weight basis) of (B3) is usually (B3)
1) 2 to 60%, (B2) 40 to 98%, (B3) 0 to 20%, preferably (B1) 4 to 40%, (B2) 60 to 96%, (B
3) 0 to 10%, more preferably (B1) 4 to 30%, (B
2) 70-96%, (B3) 0-5%.

In the present invention, for the purpose of adjusting the molecular weight and controlling the reaction, a monocarboxylic acid, a monoalcohol and the like can be used together with (A) and (B) if necessary. Specific examples thereof include monocarboxylic acids such as benzoic acid, paraoxybenzoic acid, toluenecarboxylic acid, salicylic acid, acetic acid, propionic acid and stearic acid; monoalcohols such as benzyl alcohol, toluene-4-methanol and cyclohexanemethanol. . The ratio of (A) and (B) constituting the polyester resin of the present invention is such that alcoholic hydroxyl group equivalent / carboxyl group equivalent is usually 0.6 to
The ratio may be 1.4, preferably 0.7 to 1.3, and more preferably 0.8 to 1.2. The composition ratio of (B1) in the polyester resin of the present invention is usually 1% by weight or more,
It is preferably 3 to 50% by weight, more preferably 5 to 25% by weight. When (B1) is less than 1% by weight, the plasticizer migration resistance of the toner is insufficient. Exemplifying the method for producing the polyester resin of the present invention, (A) and (B) are mixed in a predetermined ratio,
By carrying out a polyesterification reaction, the polyester resin of the present invention can be obtained. The reaction is usually 150-300 in the presence of a catalyst.
C., preferably at 170 to 280.degree. C. The reaction can be carried out under normal pressure, reduced pressure, or increased pressure, but the prescribed reaction rate (for example, about 30 to 90%)
After reaching, the reaction system is less than 200mmHg, preferably 25m
Reduce the pressure to mHg or less, more preferably 10 mmHg or less,
It is desirable to carry out the reaction.

Examples of the above-mentioned catalyst include catalysts usually used for polyesterification, for example, metals such as tin, titanium, antimony, manganese, nickel, zinc, lead, iron, magnesium, calcium and germanium; and compounds containing these metals (dibutyltin oxide). , Ortho-dibutyl titanate, tetrabutyl titanate, zinc acetate, lead acetate,
Cobalt acetate, sodium acetate, antimony trioxide, etc.). The polyester of the present invention by stopping the reaction when the properties of the reactant (eg, acid value, softening point, etc.) reach a predetermined value, or when the stirring torque or power of the reactor reaches a predetermined value. A resin can be obtained.

The polyester resin of the present invention is usually 0.5 to 3
0, preferably 2 to 20 mg KOH / g acid value and usually 5 to 10
It has a hydroxyl value of 0, preferably 10 to 60 mg KOH / g. If the acid value is less than 0.5, the toner charge will be low and
When it exceeds 0, the humidity dependency of the charge amount becomes large. Also, if the hydroxyl value is less than 5, the low temperature fixing of the toner is adversely affected, and
When it exceeds 00, the humidity dependency of the charge amount becomes large. The gel content (insoluble in tetrahydrofuran) of the polyester resin of the present invention is usually 0 to 50%, preferably 0 to 25%.
When the gel content exceeds 50%, it is difficult to synthesize polyester. The toner binder of the present invention comprises the polyester resin of the present invention, but may optionally contain other toner binder resin. Other toner binder resins include polystyrene resin, styrene-acrylic copolymer resin, styrene-butadiene copolymer resin,
Examples thereof include epoxy resins and polyester resins other than the present invention. Glass transition temperature (Tg) of the binder of the present invention
Is usually 30 to 85 ° C, preferably 40 to 80 ° C, more preferably
55 to 75 ° C. If the Tg is less than 30 ° C., the toner particles using the binder of the present invention tend to adhere to each other and aggregate (blocking), and if the Tg exceeds 85 ° C., the low temperature fixability of the toner deteriorates. The softening point of the binder of the present invention is usually 70 to 180 ° C, preferably 80 to 160 ° C. Softening point
If the temperature is lower than 70 ° C, the offset resistance of the toner tends to deteriorate, and if the temperature exceeds 180 ° C, the low-temperature fixability tends to be poor. The binder of the present invention is used as a toner component together with a colorant (C) and optionally other additives (D).

Examples of the colorant (C) include carbon black, nigrosine dye, aniline blue, red iron oxide,
Acetylene black, monoazo dye, diazo dye, quinacridone, anthraquinone dye, chalco oil blue,
Copper Phthalocyanine, Induslen Blue, Benzidine Yellow, Chrome Yellow, Ultramarine Yellow, DuPont Oil Red, Induslen Blue, Permanent Brown FG, Bryanto Farnest Scarlet, Malachite Green Oxalate, Lamp Black, Rose Bengal, Pigment Pigments or dyes such as Green B, Rhodamine B and Solvent-35, and JP-A-1-277253 and JP-A-1-15975.
Pigments or dyes other than the above described in JP-A-9 can be mentioned. The colorant (C) is usually 1 to 20 parts by weight, preferably 1 to 15 parts by weight, based on 100 parts by weight of the binder.

Other additives (D) include the following (D
1) to (D5). (D1) Release agent (offset inhibitor) A low molecular weight polyolefin (polyethylene, polypropylene) can be used, and a polyolefin having a carboxyl group is particularly preferable. The number average molecular weight of the low molecular weight polyolefin is usually 500 to 20,000, and its softening point (ring and ball method) is usually 80 to 180 ° C, preferably 100 to 160 ° C. The melt viscosity of polyethylene is usually 10 to 5,000.
cps (140 ℃), polypropylene type usually 10 ~ 5,000c
ps (160 ° C). The proportion of (D1) used is usually 0 to 10 parts by weight, preferably 0.
5 to 5 parts by weight.

(D2) Magnetic Material As a magnetic material in the case of a magnetic toner, a metal or alloy exhibiting ferromagnetism such as iron, cobalt, nickel or a compound containing these elements such as ferrite, magnetite or the like, or a ferromagnetic element Alloys containing no manganese but exhibiting ferromagnetism when subjected to an appropriate heat treatment, for example, manganese-copper-aluminum, manganese-copper-tin, and other types of alloys called Heusler alloys containing manganese and copper, or chromium dioxide. , And others. These magnetic materials are uniformly dispersed in the toner in the form of fine powder having an average particle size of 0.1 to 1 micron. When the magnetic toner is used, the content of (D2) is usually 15 to 80 parts by weight, preferably 40 to 70 parts by weight, per 100 parts by weight of the toner.

(D3) Charge control agent A conventionally known one having a positive charging property and / or a negative charging property can be used, and examples thereof include a nigrosine dye and a metal-containing dye.

(D4) Fluidity improver Silica fine powder, alumina, titanium oxide, barium titanate, magnesium titanate, calcium titanate, strontium titanate, zinc oxide, silica sand, clay, mica,
Inorganic fine particles (primary particle size 5mμ ~ 2μ) such as diatomaceous earth, chromium oxide, cerium oxide, red iron oxide, antimony trioxide, magnesium sulfide, zirconium oxide, barium sulfate, calcium carbonate, nitrogen carbide, and silicon nitride can be used. Among these, silica fine powder is preferable, and silica fine powder having a hydrophobic group on the surface is particularly preferable. The usage is
Usually 0 to 5 parts by weight per 100 parts by weight of binder, preferably
0.01 to 2 parts by weight.

(D5) Others For the purpose of improving fluidity or releasability, fatty acid metal salts, fatty acid esters and fatty acid ester waxes,
Partially saponified fatty acid ester, higher fatty acid, higher alcohol, liquid or solid paraffin wax, polyamide wax, polyhydric alcohol ester, silicon varnish, aliphatic fluorocarbon and the like can be used.
A wax having a softening point (ring and ball method) of 60 to 150 ° C. is particularly preferable.

As an example of the method for producing an electrophotographic toner, the toner is produced by the following method using the binder of the present invention, the colorant (C) and optionally other additives (D). After dry blending the respective components for the toner, the mixture is melted and kneaded by an extrusion kneader, and the kneaded product is cooled and coarsely pulverized. Next, the toner is obtained by further making it into fine particles by a jet stream type pulverizer and classifying it into particles of about 3 to 30 microns, and further adding a fluidity improver and a charge control agent to this and mixing them uniformly.

[0024]

EXAMPLES The present invention will be specifically described below with reference to production examples, examples, use examples and comparative examples, but the present invention is not limited thereto. Parts and% represent parts by weight and% by weight, respectively.

The abbreviations of the raw materials used in the production examples, examples and comparative examples are as follows. (1) Glycol A: Bisphenol A PO adduct (hydroxyl value 315) (2) Glycol B: Bisphenol A EO adduct (hydroxyl value 340) (3) Glycol C: Bisphenol F EO / PO
(1/1) adduct (hydroxyl value 320) (4) glycol D: PO adduct of bisphenol A (hydroxyl value 275) (5) TMP: trimethylolpropane (6) TPA: terephthalic acid (7) IPA: isophthalate Acid (8) FA: Fumaric acid (9) DMT: Dimethyl terephthalate (10) DSA: Dodecenyl succinic anhydride (11) TMA: Trimellitic anhydride (12) DBTO: Dibutyltin oxide (13) TBT: Tetrabutyl Titanate

The methods for measuring the properties of the polyester resins obtained in Examples and Comparative Examples are shown below. 1. Acid value and hydroxyl value The method specified in JIS K0070. However, if the sample does not dissolve, a solvent such as dioxane or tetrahydrofuran is used as the solvent. 2. Glass transition temperature (Tg) Method prescribed in ASTM D3418-82 (DSC
Law). 3. With a softening point (SP) flow tester (CFT-500, Shimadzu),
Using a 1.0 mmφ × 1.0 mm nozzle, measurement is performed at a load of 10 kg and a heating rate of 5 ° C./min, and the temperature at which 1/2 of a 1.5 g sample flows out is obtained. 4. Molecular weight Gel permeation chromatography (GP
Measured in C). The sample is Labo Plastomill (manufactured by Toyo Seiki Seisakusho), and after kneading at 120 ° C for 30 minutes, it is used. still,
The conditions for measuring the molecular weight by GPC are as follows. Equipment: Toyo Soda HLC-802A column: Column TSK gel GMH62
Book (manufactured by Toyo Soda Co., Ltd.) Measurement temperature: 25 ° C. Sample solution: 0.5 wt% THF solution Injection amount: 200 μl Detector: Refractive index detector The molecular weight calibration curve was prepared using standard polystyrene.

Production Example 1 129 parts of isocyanuric acid, 315 parts of glycol D and 0.5 part of triethylamine were added to an autoclave and maintained at 120 ° C., and 186 parts of PO was gradually injected under a nitrogen atmosphere to complete the reaction. After the reaction, volatile substances were removed by a conventional method. A heterocycle-containing oxyalkylene ether (hydroxyl value 401) diluted with glycol D was obtained. In the presence of hydroxyl and amino groups (especially when using no catalyst or amine catalyst)
The alkylene oxide (EO or PO) preferentially adds to the active hydrogen of the amino group.

Example 1 (Resin A) 700 parts of glycol D, 300 parts of oxyalkylene ether of Production Example 1 and 406 parts of TPA in a reaction vessel equipped with a thermometer, a stirrer equipped with a torque detector, a cooler and a nitrogen introducing tube. ,
DBTO (3.5 parts) was added and the reaction was carried out at 230 ° C under a nitrogen stream. When the reaction product became transparent, the reaction temperature was lowered to 200 ° C. and the polyesterification reaction was allowed to proceed under reduced pressure. When the viscosity of the reaction product gradually increased and the torque of the stirrer exhibited a predetermined value, the reaction was stopped, and the reaction product was taken out and rapidly cooled to obtain the polyester resin (A) of the present invention.

Example 2 (Resin B) The same reactor as in Example 1 was charged with 464 parts of glycol A, 434 parts of glycol B, 100 parts of tris (β-hydroxyethyl) isocyanurate (THEIC), 467 parts of IPA and 4 parts of TBT. And reacted at a temperature of 230 ° C. When the appearance of the reaction product became transparent, the reaction was continued at 200 ° C. under reduced pressure. When the torque of the stirrer reached a predetermined value, the reaction was stopped, the reaction product was taken out and rapidly cooled to obtain the polyester resin (B) of the present invention.

Example 3 (Resin C) In the same reactor as in Example 1, 560 parts of glycol A, 280 parts of glycol B, 60 parts of THEIC, 100 parts of EO 3 mol adduct of phenol / novolak resin (nucleus number 5.5), TP
A 458 parts and TBT 4 parts were added and the reaction was carried out at a temperature of 230 ° C. When the appearance of the reaction product becomes transparent, the pressure is reduced to 200.
The reaction was continued at ° C. When the torque of the stirrer reached a predetermined value, the reaction was stopped, the reaction product was taken out and rapidly cooled to obtain the polyester resin (C) of the present invention.

Example 4 (Resin D) 400 parts of glycol A, 400 parts of glycol B, 340 parts of TPA and 3.5 parts of DBTO were placed in the same reaction apparatus as in example 1 and reacted at 230 ° C. until the acid value became about 5. It was Then 19
After cooling to 0 ° C., 200 parts of THEIC and 275 parts of DSA were added to further advance the polyesterification reaction. When the viscosity of the reaction product gradually increased and the torque of the stirrer exhibited a predetermined value, the reaction was stopped, and the reaction product was taken out and rapidly cooled to obtain the polyester resin (D) of the present invention.

Example 5 (Resin E) The same reactor as in Example 1 was charged with 712 parts of glycol A and TH.
EIC80 parts, FA222 parts and DBTO2 parts at 200 ℃,
The reaction was carried out until the acid value became about 8, the reaction product was taken out and rapidly cooled to obtain the polyester resin (E) of the present invention.

Comparative Example 1 (Resin F) A comparative polyester resin F was obtained by repeating the method of Example 1 except using 850 parts of glycol D, 150 parts of TMP, 526 parts of TPA and 3.5 parts of DBPO.

Comparative Example 2 (Resin G) The same reactor as in Example 1 was charged with 950 parts of glycol B and TP.
330 parts of A was added and reacted at 230 ° C. until the acid value became 1.5. Next, it was cooled to 190 ° C., and 100 parts of TMA was added to further advance the polyesterification reaction. When the viscosity of the reaction product gradually increased and the torque of the stirrer exhibited a predetermined value, the reaction was stopped, the reaction product was taken out and rapidly cooled, and a comparative polyester resin G was obtained.

Table 1 shows the properties of polyester resins A to G, AV (acid value), Tg, Sp and Mw (weight average molecular weight).

[0036]

[Table 1]

Examples 6 to 10 and Comparative Examples 3 and 4 The polyester resins A to G obtained in Examples 1 to 5 and Comparative Examples 1 and 2 were used as binders, and toner components having the following compositions were used in the formulations shown in Table 2. Therefore, after mixing with a ball mill, melt-kneading with an extrusion kneader, cooling, coarse pulverization, fine pulverization and classification are performed, and each toner [1] to
Obtained [7]. However, for toner [2], a fluidity improver was further added after the classification and mixed with a Henschel mixer.

Carbon black "Carbon black MA-100 (manufactured by Mitsubishi Kasei Kogyo Co., Ltd.)" Chromatic pigment "Fastgen Magenta R-11 (manufactured by Dainippon Ink and Chemicals Co., Ltd.)" Charge control agent "Aizen Spyron Black TRH" (Hodogaya Chemical Co., Ltd.) "・ Anti-offset polypropylene wax" Viscole 660P (manufactured by Sanyo Kasei Co., Ltd.) "-Fluidity improver" Corodyl silica R972 (manufactured by Nippon Aerosil) "

The toner properties of the obtained toners [1] to [7] were evaluated by the following methods.

(1) Charge amount A sample obtained by frictionally charging 4 g of toner and 96 g of ferrite carrier F-100 (manufactured by Nippon Iron Powder Co., Ltd.) was measured by a blow-off charge amount measuring device manufactured by Toshiba Chemical Co.

(2) Fixability 30 g of toner and ferrite carrier F-100720 g are mixed to prepare a developer, and a commercially available copying machine (photoreceptor is an organic photoreceptor; fixing roller rotation speed is 150 mm / sec.
However, the fixing roller temperature was modified to be variable. ), The image forming test was conducted by changing the heat roller temperature, and the minimum fixing temperature and the offset generation temperature were obtained. The minimum fixing temperature here is the friction tester specified in JIS L0849-1971, and the fixing surface of the toner is rubbed with a cotton cloth for rubbing 10 times to determine the optical density of the image surface before and after rubbing by Macbeth. Measured with a reflection densitometer manufactured by the same company, and refers to the heat roller temperature when the fixing rate according to the following formula exceeds 70%. Fixing ratio (%) = (image density after rubbing) / (image density before rubbing) x 100 Also, the offset generation temperature is visually checked for the presence or absence of subsequent copy paper contamination, and the heat roller when the contamination is confirmed. Determined by temperature.

(3) Preservability 10 g of the toner is put into a screw tube of 20 cc, and the temperature is 50 ° C. × 40.
It was allowed to stand at% RH for 24 hours, and ranked in four stages according to the degree of toner aggregation. Rank A: No aggregation at all. Rank B: Aggregates slightly, but re-disperses when a light impact is applied to the screw tube. C rank: About 1/4 of the toner aggregates and does not redisperse even if a light shock is applied to the screw tube. Rank D: The degree of agglomeration is remarkable and does not redisperse even when a strong impact is applied to the screw tube.

(4) Resistance to migration of plasticizer The image after fixing is sandwiched between vinyl chloride sheets and 20 g / cm ²
Judgment is made based on the image and the degree of contamination of the vinyl chloride sheet when left for 1 week in the atmosphere of 40 ° C under the load. Rank A: No pollution at all. Rank B: There is slight pollution. Rank C: Medium pollution. Rank D: remarkable pollution.

Table 2 collectively shows the evaluation results of the toner characteristics of the toners [1] to [7].

[0045]

[Table 2]

Note: Evaluation was performed using a heat roller made of silicone rubber and a fixing machine equipped with a silicone oil supply device.

As is clear from the results shown in Table 2, the toner using the polyester resin of the present invention as a binder has toner properties such as fixing property (minimum fixing temperature and offset resistance), storability and plasticizer migration resistance. Is excellent. In particular, the toner [5] using the polyester resin of Example 5 has good plasticizer migration resistance despite having a small molecular weight. Further, the toner [6] (Comparative Example 3) using as a binder a polyester resin cross-linked with a trihydric alcohol (trimethylol propane) has offset resistance, storability and plasticizer migration resistance better than those of the toner according to the present invention. In terms of
The toner [7] (Comparative Example 4) using as a binder a polyester resin cross-linked with a trivalent carboxylic acid (trimellitic anhydride) is inferior in low-temperature fixability to the toner according to the present invention. Toners [1] of Examples 6 and 7 in Table 2,
For [2], 10,000 sheets were continuously copied. The image quality after copying 10,000 sheets was the same as the initial image quality. It can be seen that the toner using the polyester resin of the present invention does not change even after long-term friction with the carrier and has excellent durability.

[0048]

The present invention has the following effects. (1) The toner binder of the present invention has a heterocyclic structure in the molecule, and the toner obtained from this has excellent plasticizer migration resistance. That is, even if the molecular weight of the polyester, which is a usual means for improving the low-temperature fixability of the toner, is reduced, the expected decrease in the plasticizer migration resistance is small. (2) Since the toner binder of the present invention has a heterocyclic structure having excellent thermal stability in the molecule, a toner using the same has excellent offset resistance at high temperatures. (3) The toner binder of the present invention has a high Tg in spite of having a low softening point, so that the toner using the toner binder has excellent storability. (4) The toner binder of the present invention has a tough resin strength, and the toner using the toner binder is less worn by friction with the carrier and has excellent toner durability. As described above, the toner using the toner binder of the present invention has a fixability (low temperature fixability and offset resistance).
Not only that, it also has the properties required for practical use such as plasticizer migration resistance, storability, and durability, so it can be used for copiers (especially high-speed copiers) of various speeds, printers, and even full-color applications. It is useful.

[Procedure amendment]

[Submission date] November 12, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Claim 1

[Correction method] Change

[Correction content]

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0004

[Correction method] Change

[Correction content]

[0004]

Means for Solving the Problems The inventors of the present invention have conducted extensive studies to achieve the above object, and as a result, by using a polyester resin having a heterocyclic structure in the molecule as a binder, low-temperature fixing property and plasticity resistance of a toner can be obtained. The present invention has been achieved by finding that both agent transferability is compatible. That is, according to the present invention, in a toner binder comprising a polyester resin having a polycarboxylic acid component (A) and a polyol component (B) as constitutional units, at least a part of (B) has two or more active hydrogens in the molecule. An electrophotographic toner composition comprising an electrophotographic polyester-based toner binder and the above polyester-based toner binder, which is an alkylene oxide derivative (B1) of a heterocyclic compound.

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0007

[Correction method] Change

[Correction content]

In the present invention, the polyol component (B)
Is an alkylene oxide derivative (B1) of a heterocyclic compound having two or more active hydrogens in the molecule, optionally other dihydric alcohols (B2) and optionally other trihydric or higher alcohols (B3). Consists of.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0008

[Correction method] Change

[Correction content]

The alkylene oxide derivative (B1) of a heterocyclic compound having two or more active hydrogens in the molecule is
It is a reaction product of a heterocyclic compound (a) having two or more active hydrogens in the molecule and an alkylene oxide (b).

[Procedure Amendment 5]

[Document name to be amended] Statement

[Name of item to be corrected] 0027

[Correction method] Change

[Correction content]

Production Example 1 129 parts of isocyanuric acid, 315 parts of glycol D and 0.5 part of triethylamine were added to an autoclave and maintained at 120 ° C., and 186 parts of PO was gradually injected under a nitrogen atmosphere to complete the reaction. After the reaction, volatile substances were removed by a conventional method. An isocyanuric acid PO adduct (hydroxyl value 401) diluted with glycol D was obtained. In the presence of a hydroxyl group and an amino group (especially when no catalyst or an amine catalyst is used), the alkylene oxide (EO or PO) is preferentially added to the active hydrogen of the amino group.

[Procedure correction 6]

[Document name to be amended] Statement

[Correction target item name] 0028

[Correction method] Change

[Correction content]

Example 1 (Resin A) 700 parts of glycol D in a reaction vessel equipped with a thermometer, a stirrer equipped with a torque detector, a cooler and a nitrogen introducing tube, 300 parts of isocyanuric acid PO adduct of Production Example 1, 406 parts of TPA,
DBTO (3.5 parts) was added and the reaction was carried out at 230 ° C under a nitrogen stream. When the reaction product became transparent, the reaction temperature was lowered to 200 ° C. and the polyesterification reaction was allowed to proceed under reduced pressure. When the viscosity of the reaction product gradually increased and the torque of the stirrer exhibited a predetermined value, the reaction was stopped, and the reaction product was taken out and rapidly cooled to obtain the polyester resin (A) of the present invention.

Claims (4)

[Claims] 1. In a toner binder comprising a polyester resin having a polycarboxylic acid component (A) and a polyol component (B) as constitutional units, at least a part of (B) contains two or more active hydrogens in the molecule. An electrophotographic polyester toner binder which is an oxyalkylene ether (B1) of the heterocyclic compound having. 2. A glass transition point of 30 to 85 ° C. and a softening point of 70 to 180
The toner binder according to claim 1, which is at a temperature of ℃. 3. The toner binder according to claim 1, wherein the heterocyclic compound is isocyanuric acid. 4. An electrophotographic toner composition comprising the toner binder according to claim 1, a colorant (C) and optionally other additives (D).