JP2000258953A - Negatively chargeable dry toner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a dry toner having good negatively chargeable property and excellent heat-resistant storability, low temp. fixability and resistance against hot offset by coating at least a part of the toner surface with a resin containing negatively chargeable groups. SOLUTION: The toner consists of a toner binder, wax, and coloring agent. At least a part of the toner surface is coated with a resin containing negatively chargeable groups. As for the toner binder, a polyester resin, styrene resin, epoxy resin, urethane resin or the like is used. The resin containing negatively chargeable groups is, for example, a resin containing anionic functional groups such as a carboxyl group, sulfonate group, phosphate group, sulfamate group and acetylacetonate group. The main structural component of the resin is, for example, polyester, styrene (co)polymer, copolymer of styrene and diene, and (co)polymer of α,β-unsatd. carboxylic acid/alkyl (meth)acrylate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a color toner used for electrophotography, electrostatic recording, electrostatic printing, and the like.

[0002]

2. Description of the Related Art Conventionally, styrene resins, dry toners used for electrophotography, electrostatic recording, electrostatic printing, and the like have been used.
A toner binder such as polyester is melt-kneaded with a coloring agent or the like, and finely pulverized. These dry toners are frictionally charged with a carrier such as ferrite powder or a charging member, are formed on a photoconductor, and are developed into an electrostatic latent image. Then, after being transferred to paper or the like, it is heated and melted by a hot roll and fixed. At that time, if the temperature of the hot roll is too high, there is a problem (hot offset) that the toner is excessively melted and fused to the hot roll. On the other hand, if the temperature of the hot roll is too low, the toner does not melt sufficiently and the fixing becomes insufficient. From the viewpoint of energy saving and downsizing of apparatuses such as copying machines, toners having a higher hot offset generation temperature (hot offset resistance) and a lower fixing temperature (low temperature fixing property) are required. Particularly in full-color copying machines and full-color printers, since the gloss and color mixing of the image are required, the toner needs to have a lower melt viscosity, and a sharp-melting polyester toner binder is used. I have. Since hot offset is likely to occur in such a toner, silicone oil or the like is conventionally applied to a heat roll in a full-color device. However, the method of applying silicone oil to the heat roll requires an oil tank and an oil application device, and the device becomes complicated and large. It also causes deterioration of the heat roll and requires maintenance at regular intervals. Further, it is inevitable that oil adheres to copy paper, OHP (overhead projector) film, and the like. Particularly, in OHP, there is a problem of deterioration of color tone due to the adhered oil.

[0003] To achieve both the low-temperature fixing property and the hot offset resistance of a polyester toner binder,
Japanese Patent Application Laid-Open Nos. 4-48122, 7-101318, JP-A-4-21272, and JP-A-4-318012, which use a urethane-modified polyester as a toner binder, have been proposed. .

[0004]

However, although the disclosed toner has some improvement in compatibility between low-temperature fixability and hot offset resistance, it is still insufficient in compatibility with heat-resistant storage stability. It cannot be used for full color because glossiness is not exhibited.
In addition, since urethane bonds in the binder skeleton significantly reduce the negative chargeability of the binder, it is not practical.

[0005]

Means for Solving the Problems The present inventors have used a dry toner having good negative chargeability and excellent heat resistance storage stability, low-temperature fixability and hot offset resistance, especially a full-color copying machine. In this case, as a result of intensive studies to develop a dry toner having excellent image glossiness, the present invention was achieved. That is, the present invention provides a negatively chargeable toner comprising a toner binder (A), a wax (B) and a colorant (C), wherein at least a part of the toner surface is a resin (D) containing a negatively chargeable group. This is a negatively chargeable dry toner characterized by being covered.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail. In the present invention, as the toner binder (A), polyester resin (A1), styrene resin (A2), epoxy resin (A3), urethane resin (A4) and the like are used. Of these, preferred are (A1), (A
2) and (A3). From the viewpoint of the melting property at the time of fixing and the smoothness of the obtained image, polyester resin (A1) is more preferable, and from the viewpoint of achieving both low-temperature fixing property and hot offset resistance, urethane bonding and And / or polyester (A1a) modified with a urea bond.

Examples of the polyester resin (A1) include polycondensates of polyols (1) and polycarboxylic acids (2).

The polyols (1) include a diol (1-1) and a trivalent or higher polyol (1-2). As the diol (1-1), a carbon number of 2 to 1
8 alkylene glycols (ethylene glycol, 1,
2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, neopentyl glycol, 1,6-hexanediol, dodecanediol, etc.); alkylene ether glycols having 4 to 1000 carbon atoms (diethylene glycol, triethylene glycol) , Dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol, etc.); alicyclic diols having 5 to 18 carbon atoms (1,4-cyclohexanedimethanol, hydrogenated bisphenol A, etc.); Bisphenols (bisphenol A, bisphenol F, bisphenol S, etc.); alkylene oxides having 2 to 18 carbon atoms of the above alicyclic diols or bisphenols (ethylene oxide, propylene Oxides, butylene oxides, α-olefin oxides, etc.) (addition moles: 2 to 20). Preferred among these are alkylene glycols having 2 to 12 carbon atoms and alkylene oxide adducts of bisphenols having 2 to 18 carbon atoms, and particularly preferred are alkylene oxide adducts of bisphenols (particularly bisphenol A) (particularly, Of ethylene oxide or propylene oxide (2 to 3 mol adduct) and alkylene glycol having 2 to 12 carbon atoms (especially ethylene glycol, 1,2-propylene glycol, 1,4-butanediol, neopentyl glycol) It is a combination.
When used in combination, the ratio of the alkylene oxide adduct of bisphenols is usually 30 mol% or more, preferably 5 mol% or more.
It is at least 0 mol%, particularly preferably at least 70 mol%.

The trivalent or higher polyol (1-2) includes polyhydric aliphatic alcohols having 3 to 8 or more valences (glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, sorbitol, etc.); Octavalent or higher phenols (trisphenol PA, phenol novolak, cresol novolak, etc.); alkylene oxide adducts having 2 to 18 carbon atoms of the above trivalent or higher polyphenols (addition mole number is 2 to 20) and the like. No.

The polycarboxylic acids (2) include dicarboxylic acids (2-1) and tricarboxylic or higher polycarboxylic acids (2).
-2), (2-1) alone, and (2-1)
And a small amount of the mixture of (2-2) are preferred. Examples of the dicarboxylic acid (2-1) include alkylene dicarboxylic acids having 2 to 20 carbon atoms (succinic acid, adipic acid, sebacic acid, dodecane dicarboxylic acid, dodecenyl succinic acid, dodecyl succinic acid, etc.); alkenylene dicarboxylic acids (maleic acid, fumaral Acids); aromatic dicarboxylic acids (phthalic acid, isophthalic acid, terephthalic acid, naphthalenedicarboxylic acid, etc.); Preferred of these are:
C4-20 alkenylenedicarboxylic acids (especially adipic acid and dodecenylsuccinic acid) and C8-2
0 aromatic dicarboxylic acids (especially isophthalic acid and terephthalic acid). Trivalent or higher polycarboxylic acid (2-
Examples of 2) include aromatic polycarboxylic acids having 9 to 20 carbon atoms (such as trimellitic acid and pyromellitic acid). The ratio of the polyol (1) to the polycarboxylic acid (2) is usually 2/1 to 1/1, preferably 1 as the equivalent ratio [OH] / [COOH] of the hydroxyl group [OH] and the carboxyl group [COOH]. 0.5 / 1 to 1/1, more preferably 1.3
/1-1.02/1.

In the present invention, the polyester (A1a) modified with a urethane bond and / or urea bond may be a reaction product of a hydroxyl group-containing polyester (A1-1) with a polyisocyanate (3), or (A1a).
1-1) and a reaction product of polyols (1) and (3), isocyanate group-containing polyester prepolymer (A1-
A reaction product of 2) with an extender and / or a crosslinking agent (4),
And the like.

Polyester containing a hydroxyl group (A1-
Examples of 1) include polycondensates of polyols (1) and polycarboxylic acids (2), wherein the number of equivalents of hydroxyl groups in (1) is larger than the number of carboxyl groups in (2). No. The number of hydroxyl groups per molecule of the hydroxyl group-containing polyester is usually 1 or more, preferably 1.5 to 3 on average, and more preferably 1.8 on average.
~ 2.5. If the number is less than one per molecule, the molecular weight of the urethane-modified polyester becomes low, and the hot offset resistance deteriorates.

The polyols (1) and the polycarboxylic acids (2) include the same ones as those described as the constituents of the polyester resin (A1).
The same applies to preferred ones.

Further, a polyester containing a hydroxyl group (A
When reacting 1-1) with polyisocyanates (3), polyols (1) can be used in combination. It is more preferable to use the polyol (1) in combination, since the hot offset resistance is improved. Examples of the polyols (1) include those similar to those described as the constituent components of the polyester resin (A1). Of these, preferred are alkylene glycols having 2 to 12 carbon atoms and alkylene oxide adducts of bisphenols. The ratio of the hydroxyl group-containing polyester (A1-1) to the polyols (1) is defined as an equivalent ratio [OH (A1-1)] / [OH (1)] of the hydroxyl group.
It is usually 1/0 to 1/5, preferably 1/0 to 1/3, and more preferably 1 / 0.5 to 1/3.

Examples of the polyisocyanate (3) include aromatic polyisocyanates having 6 to 20 carbon atoms (excluding carbon in the NCO group, the same applies hereinafter), aliphatic polyisocyanates having 2 to 18 carbon atoms, and 4 to 15 carbon atoms. Alicyclic polyisocyanates, araliphatic polyisocyanates having 8 to 15 carbon atoms and modified products of these polyisocyanates (urethane group, carbodiimide group, allophanate group, urea group, buret group, uretdione group, uretoimine group, isocyanate) Examples thereof include a modified product containing a nurate group and an oxazolidone group), a product obtained by blocking these NCO groups with a compound capable of leaving (an oxime compound or a lactam compound), and a mixture of two or more of these compounds.

Specific examples of the aromatic polyisocyanate include 1,3- and / or 1,4-phenylene diisocyanate, 2,4- and / or 2,6-tolylene diisocyanate (TDI), crude TDI, ,
4′- and / or 4,4′-diphenylmethane diisocyanate (MDI), crude MDI [crude diaminophenylmethane [condensation product of formaldehyde and aromatic amine (aniline) or a mixture thereof; diaminodiphenylmethane and a small amount (eg, 20% by weight) of a mixture with a tri- or higher functional polyamine]: polyallyl polyisocyanate (PAPI)], 1,5-naphthylene diisocyanate, 4,4 ′, 4 ″ -triphenylmethane triisocyanate, m -And p-isocyanatophenylsulfonyl isocyanate.

Specific examples of the above aliphatic polyisocyanate include ethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate (H
DI), dodecamethylene diisocyanate, 1,6,1
1-undecane triisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, lysine diisocyanate, 2,6-diisocyanatomethyl caproate, bis (2-isocyanatoethyl) fumarate, bis (2-isocyanatoethyl) carbonate And aliphatic polyisocyanates such as 2-isocyanatoethyl-2,6-diisocyanatohexanoate.

Specific examples of the alicyclic polyisocyanate include isophorone diisocyanate (IPDI), dicyclohexylmethane-4,4'-diisocyanate (hydrogenated MDI), cyclohexylene diisocyanate,
Methylcyclohexylene diisocyanate (hydrogenated TD
I), bis (2-isocyanatoethyl) -4-cyclohexene-1,2-dicarboxylate, 2,5- and / or 2,6-norbornane diisocyanate.

Specific examples of the araliphatic polyisocyanate include m- and / or p-xylylene diisocyanate (XDI), α, α, α ′, α′-tetramethylxylylene diisocyanate (TMXDI). Can be

The modified polyisocyanate includes modified MDI (urethane-modified MDI, carbodiimide-modified MDI, trihydrocarbyl phosphate-modified MD).
I), modified products of polyisocyanates such as urethane-modified TDI, and mixtures of two or more thereof (for example, a combination of modified MDI and urethane-modified TDI (isocyanate-containing prepolymer)).

Examples of the above isocyanate blocking compounds include those obtained by blocking the NCO group of the above isocyanate compound with an oxime compound (methyl ethyl ketoxime, methyl ethyl ketoxime), ε-caprolactam, a phenol derivative or the like.

Of these, preferred are aromatic polyisocyanates having 6 to 15 carbon atoms, aliphatic polyisocyanates having 4 to 12 carbon atoms, alicyclic polyisocyanates having 4 to 15 carbon atoms, and block compounds thereof. Particularly preferred are TDI, MDI, HDI, hydrogenated MD
I, IPDI, and their methyl ethyl ketoxime-blocks.

The ratio of polyisocyanates (3) is equivalent ratio [NCO] / [OH] of isocyanate group [NCO], total [OH] of hydroxyl group-containing polyester (A1-1) and polyol (1). ], Usually 1/2 to 2/1,
It is preferably from 1.5 / 1 to 1 / 1.5, more preferably from 1.2 / 1 to 1 / 1.2. [NCO] / [OH] is 2
If it exceeds or less than １ ／, the molecular weight of the urethane-modified polyester becomes low, and the hot offset resistance deteriorates.

Further, for the purpose of adjusting the molecular weight of the urethane-modified polyester, a monool may be partially used in combination. Monools include alkyl alcohols (methanol, ethanol, butanol, octanol, lauryl alcohol, stearyl alcohol, etc.); alkyl alcohols (benzyl alcohol, etc.); alkylene oxide adducts of phenols (ethylene oxide adducts of phenol, nonylphenol Ethylene oxide adduct) and the like.

The reaction product of the isocyanate group-containing polyester prepolymer (A1-2) and the extender and / or the crosslinking agent (4) is obtained by converting the hydroxyl group-containing polyester (A1-1) and the isocyanates (3) into NCO groups. (A1-2) by reacting (3) in excess so that is left, and then reacting (4) to obtain (A1-2). As the hydroxyl group-containing polyester (A1-1) and the isocyanate (3), those described in the description of the reaction product of the hydroxyl group-containing polyester (A1-1) and the polyisocyanate (3) are used. And the preferable ones are also the same.

When a polyisocyanate is reacted with a hydroxyl group-containing polyester to obtain an isocyanate group-containing polyester prepolymer (A1-2), the ratio of the polyisocyanate is determined by the ratio of the isocyanate group [NCO] to the hydroxyl group [OH] of the hydroxyl group-containing polyester. Molar ratio [NCO] / [OH]
5/1 to 1/1, preferably 4/1 to 1.
2/1, more preferably 2.5 / 1 to 1.5 / 1.

The number of reactive groups per molecule in the prepolymer (A1-2) is usually one or more, preferably 1.5 to 3 on average, and more preferably 1.8 on average.
~ 2.5. By setting the above range, (A1-
The molecular weight of the elongation and / or cross-linking reaction product in 2) is increased, and the hot offset resistance is improved.

Examples of the extender and / or crosslinking agent (4) include amines (4-1), polyols (4-2), polymercaptans (4-3), water (4-4) and 4- (4).
(4-5) wherein one amino group is blocked by a compound capable of leaving. Among these, preferred are (4-1), (4-2), (4-4) and (4-5), and more preferred are (4-)
1), (4-4) and (4-5), and particularly preferred are blocked amines (4-5) and water (4-4).

As the amines (4-1), diamines (4)
-1a) tri- or hexavalent or higher polyamine (4-
1b), amino alcohol (4-1c), aminomercaptan (4-1d), amino acid (4-1e) and the like.

The diamine (4-1a) has 6 carbon atoms.
To 23 aromatic diamines (phenylenediamine, diethyltoluenediamine, 4,4'diaminodiphenylmethane, etc.); alicyclic diamines having 5 to 20 carbon atoms (4,4 '
-Diamino-3,3'dimethyldicyclohexylmethane, diaminocyclohexane, isophoronediamine, and the like; and aliphatic diamines having 2 to 18 carbon atoms (ethylenediamine, tetramethylenediamine, hexamethylenediamine, and the like).

Triamine or hexavalent or higher polyamine (4
As -1b), diethylenetriamine, triethylenetetramine and the like can be mentioned. Amino alcohol (4
-1c) includes those having 2 to 12 carbon atoms,
Specific examples include ethanolamine and hydroxyethylaniline. Amino mercaptan (4-1
Examples of d) include those having 2 to 12 carbon atoms, and specific examples include aminoethyl mercaptan and aminopropyl mercaptan. Amino acid (4-1e)
Examples thereof include those having 2 to 12 carbon atoms, and specific examples thereof include aminopropionic acid and aminocaproic acid.

Among these amines (4-1), preferred are 4-1a (especially 4,4'diaminodiphenylmethane, isophoronediamine and ethylenediamine) and a mixture of 4-1a and a small amount of 4-1b (especially diethylenetriamine). It is. The ratio of the mixture is 4-1a and 4
The molar ratio of -1b is usually 100/0 to 100/10, preferably 100/0 to 100/5.

Examples of the polyols (4-2) include the same ones as the polyols (1) described above, and preferred ones are also the same. Examples of the polymercaptans (4-3) include ethylenedithiol, 1,4-butanedithiol, and 1,6-hexanedithiol. 4
Examples of the compound (4-5) in which the amino group of -1 is blocked with a compound which can be eliminated include the amines of 4-1a to 4-1e and ketones having 3 to 8 carbon atoms (acetone, methyl ethyl ketone, Ketimine compounds and oxazoline compounds obtained from methyl isobutyl ketone.

The ratio of the extender and / or the crosslinking agent (4) is determined by the following formula: (4) the number of moles of NCO groups [NCO] in the isocyanate group-containing polyester prepolymer (A1-2).
The ratio [NCO] / [B] of the number of moles of the active hydrogen group [B] in the compound is usually 1/2 to 2/1, preferably 1.5 / 1 to 1/1.
1.5, more preferably 1.2 / 1 to 1 / 1.2. When (4) is water (4-1d), water is treated as a divalent active hydrogen compound. By setting [NCO] / [B] in the above range, the hot offset resistance is improved.

Further, if necessary, a reaction terminator can be used together with (D). Examples of the reaction terminator include monoisocyanates (lauryl isocyanate, phenyl isocyanate, etc.), monoepoxides (butyl glycidyl ether, etc.), monoamines (diethylamine, dibutylamine, butylamine, laurylamine, etc.); those obtained by blocking monoamines (ketimine compounds, etc.) ;
Monool (methanol, ethanol, isopropanol, butanol, phenol; monomercaptan (butyl mercaptan, lauryl mercaptan, etc.)).

The hydroxyl value of the polyester resin (A1) is usually 5 or more, preferably 10 to 120, and more preferably 20 to 80. If it is less than 5, it is disadvantageous in terms of compatibility between heat-resistant storage stability and low-temperature fixability. The acid value of (A) is usually 0 to 120, preferably 0 to 50, more preferably 5 to 5.
~ 30.

In the present invention, the styrene resin (A2)
Can be obtained by copolymerizing styrenes and a nitrile group-containing monomer. As styrenes, styrene, α-methylstyrene, p-methylstyrene, m-methylstyrene, p-methoxystyrene, p-hydroxystyrene,
Examples include p-acetoxystyrene, vinyltoluene, ethylstyrene, phenylstyrene, benzylstyrene and the like. Examples of the nitrile group-containing monomer include (meth) acrylonitrile and cyanostyrene. In addition to these monomers, alkyl (C1-22) esters of unsaturated carboxylic acids [methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, octyl (meth) acrylate, decyl (meth) acrylate , Lauryl (meth) acrylate, tetradecyl (meth) acrylate, hexadecyl (meth) acrylate, stearyl (meth) acrylate,
Behenyl (meth) acrylate, etc.), vinyl ester monomers [vinyl acetate, etc.], vinyl ether monomers [vinyl methyl ether, etc.], halogen-containing vinyl monomers [vinyl chloride, etc.], diene monomers (butadiene, isobutylene, etc.), etc. May be used in combination.

Examples of the epoxy resin (A3) include addition condensation products of bisphenols (bisphenol A, bisphenol F, bisphenol S, etc.) and epichlorohydrin. As the polyurethane (A4),
Polyadducts of polyols (1) and polyisocyanates (3) are exemplified. Examples of (1) and (3) include the same ones as described above, and preferred ones are also the same.

In the present invention, the toner binder (A)
The polystyrene-equivalent peak molecular weight measured by the GPC method is usually 1,000 to 10,000, preferably 1500 to 10,000.
It is 10,000, More preferably, it is 2000-8000. If it is less than 1,000, the heat-resistant storage stability deteriorates, and
If it exceeds, the low-temperature fixability deteriorates. The glass transition point (Tg) of the toner binder of the present invention is usually 35 to 85 ° C, preferably 45 to 70 ° C. If the temperature is lower than 35 ° C., the heat-resistant storage stability of the toner deteriorates, and if it exceeds 85 ° C., the low-temperature fixability becomes insufficient. The storage elastic modulus (G ′) of the toner binder was 10,000 dyn at a measurement frequency of 20 Hz.
The temperature (TG ′) at which e / cm 2 is reached is usually 100 ° C. or higher, preferably 110 to 200 ° C. If the temperature is lower than 100 ° C., the hot offset resistance deteriorates. The viscosity of the toner binder is 100 at a measurement frequency of 20 Hz.
The temperature (Tη) at which 0 poise is reached is usually 180 ° C. or lower, preferably 90 to 160 ° C. If it exceeds 180 ° C., the low-temperature fixability deteriorates. That is, TG ′ is preferably higher than Tη from the viewpoint of achieving both low-temperature fixability and hot offset resistance. In other words, the difference between TG ′ and Tη (T
G′-Tη) is preferably 0 ° C. or higher. It is more preferably at least 10 ° C, particularly preferably at least 20 ° C.
The upper limit is not particularly limited. In addition, the difference between Tη and Tg is preferably from 0 to 100 ° C. from the viewpoint of achieving both heat-resistant storage stability and low-temperature fixability. The temperature is more preferably from 10 to 90 ° C, particularly preferably from 20 to 80 ° C.

Hereinafter, the resin (D) having negative chargeability will be described in detail. In the present invention, the resin (D) having negative chargeability includes a carboxyl group, a sulfonic acid group,
Examples of the resin include a resin containing an anionic functional group such as a phosphate group, a sulfamic acid group, and an acetylacetonate group.

The main skeleton component of (D) includes polyester (D1), (co) polymer of styrenes (D2), copolymer of styrenes and dienes (D3), α, β-unsaturated Carboxylic acid / alkyl (meth) acrylate (co)
Polymer (D4) and the like.

The polyester (D1-1) containing a carboxyl group is a polycondensate of a polyol (1) and a polycarboxylic acid (2), and the carboxyl group in (2) is a hydroxyl group in (1). The polycarboxylic acid (2-2) having a valency of 3 or more is reacted with a compound used in excess of the number of equivalents of (1) or a compound used in excess of the number of hydroxyl groups in (1) than the carboxyl group in (2). And the like.
Polyols (1), polycarboxylic acids (2) and 3
Examples of the polycarboxylic acid (2-2) having a valency of equal to or higher than those described as the constituent components of the polyester resin (A1) are also preferable. Polyols (1) and polycarboxylic acids (2)
And the carboxyl group in (2) is replaced by (1)
Although the ratio of the polyols (1) and the polycarboxylic acid (2) used in excess of the number of equivalents of the hydroxyl groups in the
[OH] / carboxyl group [COOH] equivalent ratio [OH] /
[COOH] is usually 1/2 to 1/1, preferably 1
/1.8 to 1 / 1.02, more preferably 1 / 1.5
１ ／ 1 / 1.05. In the case where the number of equivalents of the hydroxyl group in (1) is used in excess of the carboxyl group in (2), 3
The ratio of the polyols (1) to the polycarboxylic acid (2) obtained by reacting the polycarboxylic acids (2-2) having a valency or higher is the equivalent ratio of the hydroxyl group [OH] to the carboxyl group [COOH].
[OH] / [COOH] is usually 2/1 to 1/1, preferably 1.8 / 1 to 1.02 / 1, and more preferably 1.5 / 1 to 1.05 / 1. The ratio of the trivalent or higher polycarboxylic acid (2-2) is determined by the molar ratio of the polyol (1) to the polycondensate of the polycarboxylic acid (2) [2-
2] / [OH] is usually 2/1 to 1.02 / 1, preferably 2/1 to 1.1 / 1, and more preferably 2/1.
１．５1.5 / 1.

Polyesters containing sulfonic acid groups (D
Examples of 1-2) include polycondensates of polyols (1), polycarboxylic acids (2) and / or polycarboxylic acids (2-3) containing a sulfonic acid group.
Examples of the polycarboxylic acids having a sulfonic acid group (2-3) include an ethylene oxide adduct of 4-sulfoisophthalic acid, a propylene oxide adduct of 4-sulfoisophthalic acid, and an ethylene / propylene oxide addition of 4-sulfoisophthalic acid. And body. Examples of the polyols (1) and the polycarboxylic acids (2) are the same as those described as the constituent components of the polyester resin (A1), and the preferable ones are also the same. The ratio of the polyols (1) to the polycarboxylic acids (2) and / or the sulfonic acid group-containing polycarboxylic acids (2-3) is equivalent ratio [OH] / hydroxyl group [OH] to carboxyl group [COOH]. As [COOH],
Usually 1/2 to 1/1, preferably 1 / 1.8 to 1/1.
02, more preferably 1 / 1.5 to 1 / 1.05.

Styrene (co) polymers containing carboxyl, sulfonic, phosphoric, sulfamic and / or acetylacetonato groups (D2-1)
Examples thereof include (co) polymers of the polymerizable monomer (d2-1) having an anionic functional group and styrenes.

As (d2-1), for example, α, β-
Unsaturated carboxylic acids [monobasic acids such as (meth) acrylic acid, crotonic acid, etc., polybasic acids such as maleic acid, itaconic acid and fumaric acid or acid anhydrides thereof, monoalkyl esters of these polybasic acids and the like], Polymerizable monomers having a sulfonic acid group [sodium alkyl allyl sulfosuccinate, 3-methylpropylacrylamide sulfonic acid, etc.], and polymerizable monomers having a phosphate group [monophosphate of 2-hydroxyethyl (meth) acrylate] (Di) ester, etc.], a polymerizable monomer having a sulfamic acid group [such as 2-ethylhexyl (meth) acrylate ester of a sulfamic acid-ethylene oxide adduct], a monomer having an acetylacetonato group [2-acetyl] Acetonatoethyl (meth) acrylate, etc.]. Of these, preferred are α, β-unsaturated carboxylic acids, polymerizable monomers having a sulfonic acid group, and polymerizable monomers having a phosphoric acid group, and particularly preferred are (meth) acrylic acid, Maleic anhydride, itaconic acid, maleic anhydride monoalkyl ester, 3-methylpropylacrylamide sulfonic acid, and mono (di) phosphate of 2-hydroxyethyl (meth) acrylate.

The (co) polymer of the styrenes (D2-1)
As styrenes constituting the styrene, styrene, α-methylstyrene, p-methylstyrene, m-methylstyrene,
p-methoxystyrene, p-hydroxystyrene, p-
Examples include acetoxystyrene, vinyltoluene, ethylstyrene, phenylstyrene, benzylstyrene and the like. Of these, styrene and a combination of styrene and other styrenes are preferred, and styrene is particularly preferred.

In (D2-1), (d2-1),
A small amount of other monomers can be copolymerized with the styrenes. Other copolymerizable monomers include alkyl (meth) acrylate [methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, Stearyl (meth) acrylate, etc.], substituted alkyl (meth) acrylates [hydroxyethyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, etc.], unsaturated nitriles [(meth) acrylonitrile, etc.], vinyl esters [vinyl acetate] And the like, vinyl ethers [such as butyl vinyl ether], and α-olefins [such as hexene, octene, and dodecene]. Preferred among these are alkyl (meth) acrylates, substituted alkyl (meth) acrylates, and unsaturated nitriles, and more preferably, alkyl (meth) acrylates having a C1-C12 alkyl group, and hydroxyethyl (meth) Acrylate and (meth) acrylonitrile. The copolymerization ratio of a polymerizable monomer (d2-1) having a carboxyl group, a sulfonic acid group, a phosphoric acid group, a sulfamic acid group and / or an acetylacetonate group, and other monomers copolymerizable with styrenes is as follows. , Usually (d2-1) is 5 to 99
% By weight, 1 to 95% by weight of styrenes and 0 to 10% by weight of other monomers, preferably (d2-1) is 10 to 98% by weight, styrenes is 2 to 90% by weight, Other monomers are 0 to 5% by weight.

A copolymer of styrenes and dienes containing a carboxyl group, a sulfonic acid group, a phosphoric acid group, a sulfamic acid group and / or an acetylacetonate group (D3
Examples of -1) include copolymers of the above-mentioned polymerizable monomer (d2-1) having an anionic functional group with styrenes and dienes.

As the styrenes constituting (D3-1), those similar to (D2-1) above can be mentioned, and preferred ones are also the same. Dienes include butadiene,
And isoprene, chloroprene, hexadiene and octadiene. Preferred among these are butadiene, isoprene and chloroprene, and particularly preferred are butadiene and isoprene. In (D3-1), a small amount of other monomers can be copolymerized with the (d2-1), styrenes and dienes. Examples of the other copolymerizable monomer include those similar to the above (D2-1), and preferred ones are also the same. Carboxyl group, sulfonic acid group,
A phosphoric acid group, a sulfamic acid group and / or an acetylacetonate group are converted to a polymerizable monomer (d2-1), styrenes,
The copolymerization ratio of other monomers copolymerizable with dienes is usually 5 to 98% by weight for (d2-1) and 1 to 94% by weight for styrenes.
% By weight, 1 to 40% by weight of dienes and 0 to 10% by weight of other monomers, and preferably (d2-1) is 1% by weight.
0 to 96% by weight, 2 to 85% by weight of styrenes, 2 to 30% by weight of dienes, and 0 to 5% by weight of other monomers.

(Co) polymer of α, β-unsaturated carboxylic acid / alkyl (meth) acrylate containing carboxyl group, sulfonic acid group, phosphoric acid group, sulfamic acid group and / or acetylacetonato group (D4- As 1), a polymer of the polymerizable monomer (d2-1) having an anionic functional group such as poly (meth) acrylic acid, and a copolymer of (d2-1) and an alkyl (meth) acrylate Coalescence and the like. Examples of the alkyl (meth) acrylate constituting (D4-1) include alkyl (meth) acrylate [methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, and 2- (meth) acrylate.
Ethylhexyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, etc.] and substituted alkyl (meth) acrylates [hydroxyethyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, etc.]. Of these, preferred are alkyl (meth) acrylates having a C1-C12 alkyl group, and hydroxyethyl (meth).
Acrylate. In (D4-1), (meta)
A small amount of other monomers can be copolymerized with the acrylate. Other copolymerizable monomers include unsaturated nitriles [such as (meth) acrylonitrile], vinyl esters [such as vinyl acetate], vinyl ethers [such as butyl vinyl ether], α-olefins [hexene, octene, dodecene]. Etc.].

Preferred among these are unsaturated nitriles, more preferably (meth) acrylonitrile. Other polymerizable monomers capable of copolymerizing a carboxyl group, a sulfonic acid group, a phosphoric acid group, a sulfamic acid group and / or an acetylacetonato group with a polymerizable monomer (d2-1) and an alkyl (meth) acrylate The copolymerization ratio of (d2-1) is usually 5 to 100% by weight, alkyl (meth) acrylate is 0 to 95% by weight, and other polymerizable monomers are 0 to 10% by weight. (D
2-1) is 10 to 96% by weight, alkyl (meth) acrylate is 0 to 90% by weight, and other monomers are 0 to 5% by weight.

In the present invention, the acid value of the negatively chargeable resin (D) is usually from 50 to 800, preferably from 60 to 800.
750, particularly preferably 70 to 700. (D)
The weight average molecular weight in terms of polystyrene according to the GPC method is usually 1,000 to 1,000,000, preferably 1
000-800,000, more preferably 50,
000 to 500,000.

In the present invention, known waxes (B) can be used, for example, polyolefin wax (polyethylene wax, polypropylene wax, etc.); long-chain hydrocarbon (paraffin wax, sasol wax, etc.); carbonyl group-containing wax. (Carnauba wax, montan wax, distearyl ketone, etc.)
And the like. The melting point of wax is usually 40 to 16
0 ° C, preferably 50 to 120 ° C, more preferably 60 to 90 ° C. The melt viscosity of the wax is 5 to 1 as a measured value at a temperature 20 ° C. higher than the melting point.
000 cps is preferred, and more preferably 10 to 10 cps.
0 cps. The content of the wax (B) in the toner is usually 2 to 30% by weight, preferably 3 to 25% by weight.
It is.

As the colorant (C) of the present invention, known dyes, pigments and magnetic powders can be used. Specifically, carbon black, Sudan Black SM, Fast Yellow-G, Benzidine Yellow, Pigment Yellow, India First Orange, Irgasin Red,
Balanitoaniline red, toluidine red, carmine FB, pigment orange R, lake red 2G, rhodamine FB, rhodamine B lake, methyl violet B lake, phthalocyanine blue, pigment blue,
Examples include Priliant Green, Phthalocyanine Green, Oil Yellow GG, Kayaset YG, Orazol Brown B, Oil Pink OP, magnetite, and iron black. The content of the colorant (C) in the toner is usually 2 to 1
It is 5% by weight, preferably 3 to 10% by weight.

An example of the method for producing the toner binder (A) of the present invention will be described. The polyester resin (A1) is obtained by mixing a polycarboxylic acid and a polyol with tetrabutoxy titanate,
It is obtained by heating to 150 to 280 ° C. in the presence of a known esterification catalyst such as dibutyltin oxide and performing dehydration condensation. It is also effective to reduce the pressure in order to improve the reaction rate at the end of the reaction.

The polyester (A1a) modified with a urethane bond and / or a urea bond can be obtained by a one-shot method,
It can be obtained by a known method such as a prepolymer method.
At 0 to 140 ° C., the polyisocyanate (3) is added to (A1) and optionally used polyols (2) for 10 times.
It is obtained by reacting for minutes to 48 hours. At the time of the reaction, a solvent can be used if necessary. Examples of usable solvents include aromatic solvents (toluene, xylene, etc.); ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.); esters (ethyl acetate, etc.); amides (dimethylformamide, dimethylacetamide, etc.) and ethers And the like (e.g., tetrahydrofuran).

(A1a) can be obtained by reacting an isocyanate group-containing polyester prepolymer (A1-2) with an elongating agent and / or a crosslinking agent (4). Isocyanate group-containing polyester prepolymer (A1-
2) can be obtained by using an excess of isocyanates (3) in the same production method as (A1a). (A1-
A reaction product of 2) with the elongating agent and / or the crosslinking agent (4) can be obtained by reacting at 0 to 140 ° C. for 10 minutes to 48 hours in the presence of water. This reaction may be performed subsequent to the prepolymer reaction, or may be performed by adding (4) to the prepolymer (A1-2) and then dispersing it in an aqueous medium.

The method for producing the resin (D) having a negative chargeability of the present invention will be exemplified. Examples of the polyester (D1-1) containing a carboxyl group and the polyester (D1-2) containing a sulfonic acid group include polyester resin (A1).
It can be obtained by the same manufacturing method as described above.

Styrene (co) polymers containing carboxyl, sulfonic, phosphoric, sulfamic and / or acetylacetonato groups (D2-
1) a copolymer of styrenes and dienes containing the above anionic functional group (D3-1), and α, β-unsaturated carboxylic acid / alkyl (meth) acrylate containing anionic functional group The (co) polymer (D4-1) is
It is obtained by copolymerizing constituent monomers with a known radical initiator. Examples of the radical initiator include azo initiators (azobisisobutyronitrile, azobisvaleronitrile, etc.) and peroxide initiators (benzoyl peroxide, t-butyl perbenzoate, di-t-butyl peroxide, di- t-butyl peroxyhexahydroterephthalate) and the like. Known polymerization methods such as solution polymerization, bulk polymerization, suspension polymerization, and emulsion polymerization can be used as the polymerization method. Solvents used for solution polymerization include aromatic solvents (toluene, xylene, etc.); ketone solvents (acetone, methyl ethyl ketone,
Methyl isobutyl ketone, cyclohexanone, etc.); halogen solvents (such as dichloroethane); and amide solvents (such as dimethylformamide).
When a solvent is used, the solvent is distilled off under normal pressure and reduced pressure after polymerization. When obtained by suspension polymerization, polymerization can be carried out in water using an inorganic dispersant such as calcium carbonate or calcium phosphate or an organic dispersant such as polyvinyl alcohol or methylated cellulose. The polymerization temperature is selected depending on the molecular weight of the radical initiator and the toner binder to be used, but is usually 5 to 200C, preferably 50 to 170C. The polymerization time is usually 1 to 4
8 hours, preferably 2 to 24 hours

The negatively chargeable dry toner of the present invention is characterized in that at least a part of the surface of the toner is covered with a resin (D) containing a negatively chargeable group. The coating in D) can be performed by the method exemplified below. A method in which (D) is added and kneaded when toner components are mixed, and then (D) is exposed to the surface by pulverization. When mixing (toning) toner components, (D) is added and kneaded. A method of transferring (D) to the surface during wet granulation in an aqueous medium, wherein (D) is dissolved in a solvent in which the toner is insoluble and the toner is insoluble, and (D) is further dispersed and stirred for a predetermined time After that, the solvent is filtered or distilled off to coat the surface of (D). Of the above methods, the method is preferable because the entire toner surface can be efficiently coated. When wet granulation of toner is performed to reduce the particle size of the toner, sharpen the particle size distribution, and the like for improving image quality and improving resolution, a method or a method is preferable. As the solvent used in the method, water alone may be used, but when (D) is hardly soluble, a solvent miscible with water may be used in combination. Miscible solvents include alcohols (methanol, isopropanol,
Ethylene glycol), dimethylformamide, tetrahydrofuran, cellosolves (eg, methylcellosolve), lower ketones (eg, acetone, methylethylketone), and the like. The amount of solvent used is 1 for the entire toner.
It is usually 50 to 2000 parts by weight, preferably 100 to 1000 parts by weight, based on 00 parts. If the amount is less than 50 parts by weight, the dispersion state of the toner is poor, and toner particles having a predetermined particle size cannot be obtained. If it exceeds 20,000 parts by weight, it is not economical.
The temperature at which the toner is dispersed in the solvent in which (D) is dissolved is usually 0 to 150 ° C (under pressure), preferably 40 to 150 ° C.
98 ° C. The time for dispersing the toner is usually from 1 minute to
It is 12 hours, preferably 10 minutes to 6 hours. The solvent is
After the above operation, the solution is filtered or distilled off.
In order to sufficiently perform the coating with, a method of distilling off the solvent is preferable. The temperature at which the solvent is distilled off is usually 0 to 140.
° C, preferably 25 to 100 ° C. In order to carry out the distillation quickly, the distillation may be performed under reduced pressure.

In the dry toner of the present invention, in addition to the wax (B) and the colorant (C), a charge control agent and a fluidizing agent may be further used. Known charge control agents include nigrosine dyes, quaternary ammonium salt compounds, quaternary ammonium base-containing polymers, metal-containing azo dyes, salicylic acid metal salts, sulfonic acid group-containing polymers, fluorinated polymers, and halogen substitution. Examples include aromatic ring-containing polymers. The content of the charge control agent is usually 0 to 5% by weight. Known fluidizers such as colloidal silica, alumina powder, titanium oxide powder, and calcium carbonate powder can be used. The content of the fluidizing agent is usually 0 to 5% by weight.

In the present invention, the particles formed by the elongation reaction and / or the crosslinking reaction of (A) have a median diameter (d50) of usually 2 to 2 from the viewpoint of developability and resolution.
0 μm, preferably 3 to 15 μm, more preferably 4 μm
８8 μm. The shape is preferably spherical from the viewpoint of fluidity.

The dry toner of the present invention can be produced by the following method. Kneading and pulverizing method After dry blending toner materials, they are melt-kneaded, then finely pulverized using a jet mill or the like, and further classified by wind power to obtain a color toner. Dispersion granulation method (for example, JP-A-9-15902) The method disclosed in the publication) After dissolving and dispersing the toner material in a solvent in which the toner binder is soluble, dispersing the toner material in a poor solvent (for example, water) of the toner binder with stirring, then distilling off the solvent to form toner particles, and after cooling, , Solid-liquid separation and drying to obtain a color toner. Of these, preferred is the dispersion granulation method, and particularly preferred is the dispersion granulation method in which the poor solvent serving as the dispersed phase is an aqueous medium. As a method of stably forming a toner dispersion in an aqueous medium, a method of adding a composition of a toner raw material to an aqueous medium, dispersing by a shearing force, and passing the composition of a toner raw material through a microporous body Examples thereof include a method of dispersing in an aqueous dispersion. Toner binder (A) and other toner raw materials (colorant, release agent, charge control agent, etc.)
May be mixed when forming a dispersion in an aqueous medium, but it is more preferable to mix the toner raw materials in advance and then add and disperse the mixture in the aqueous medium.
Further, other toner raw materials such as a coloring agent, a release agent, and a charge control agent do not necessarily need to be mixed when forming particles in an aqueous medium, and may be added after forming the particles. Good. For example, after forming particles containing no coloring agent, a coloring agent may be added by a known dyeing method.

The method of dispersion is not particularly limited, but known equipment such as a low-speed shearing type, a high-speed shearing type, a friction type, a high-pressure jet type, and an ultrasonic wave can be applied. In order to make the particle size of the dispersion 2 to 20 μm, a high-speed shearing type is preferred. When a high-speed shearing disperser is used, the number of rotations is not particularly limited, but is usually 1000 to 30000 rpm
m, preferably 5000 to 20000 rpm. The dispersion time is not particularly limited, but is usually 0.1 to 5 minutes in the case of a batch system. The temperature at the time of dispersion is usually 0
To 150 ° C (under pressure), preferably 40 to 98 ° C.
A higher temperature is preferred in that the viscosity of the dispersion comprising the toner binder (A) is lower and the dispersion is easier.

The amount of the aqueous medium to be used per 100 parts of the toner binder (A) is usually 50 to 2,000 parts by weight, preferably 100 to 1,000 parts by weight. If the amount is less than 50 parts by weight, the dispersion state of (A) is poor and toner particles having a predetermined particle size cannot be obtained. If it exceeds 2000 parts by weight, it is not economical. Further, if necessary, a dispersant can be used. The use of a dispersant is preferred in that the particle size distribution becomes sharp and the dispersion is stable. As dispersants, water-soluble polymers (polyvinyl alcohol, hydroxyethyl cellulose, etc.), inorganic powders (calcium carbonate powder, calcium phosphate powder, hydroxyapatite powder, silica fine powder, etc.) and surfactants (sodium dodecylbenzenesulfonate, Known materials such as sodium lauryl sulfate and sodium oleate can be used. When a dispersant is used, the dispersant can be left on the surface of the toner particles. However, it is preferable to remove the dispersant by washing after elongation and / or crosslinking reaction from the viewpoint of the charged surface of the toner.

Further, in order to lower the viscosity of the dispersion comprising the toner binder (A), a solvent in which (A) is soluble can be used. The use of a solvent is preferred in that the particle size distribution becomes sharp. The solvent has a boiling point of 100 ° C.
It is preferable that the organic solvent has a volatility of less than that it is easily removed. Examples of the solvent include ethyl acetate, acetone, methyl ethyl ketone and the like. The amount of the solvent used per 100 parts of the toner binder (A) is usually from 0 to 30.
0 parts, preferably 0 to 100 parts, more preferably 25 parts
~ 70 parts. If a solvent is used, elongation and / or
Alternatively, after the crosslinking reaction, the mixture is removed by heating under normal pressure or reduced pressure.

The toner particles formed by elongating and / or cross-linking the dispersion are subjected to solid-liquid separation using a centrifuge, a spacra filter, a filter press or the like, and the resulting powder is dried to obtain the dry powder of the present invention. A toner is obtained. As a method for drying the obtained powder, a known apparatus such as a fluidized bed dryer, a reduced pressure dryer, and a circulating dryer can be used. If necessary, the particles can be classified using a wind classifier or the like to obtain a predetermined particle size distribution.

The dry toner of the present invention may optionally contain iron powder,
Glass beads, nickel powder, ferrite, magnetite, and resins (acrylic resin, silicone resin, etc.)
Is mixed with carrier particles such as ferrite coated on the surface thereof and used as a developer for an electric latent image. In addition, instead of the carrier particles, friction with a member such as a charging blade can be performed to form an electric latent image.
The dry toner of the present invention is fixed on a support (paper, polyester film, or the like) by a copying machine, a printer, or the like to form a recording material. As a method for fixing to a support, a known hot roll fixing method, flash fixing method, or the like can be applied.

Hereinafter, the present invention will be further described with reference to examples, but the present invention is not limited to these examples. Hereinafter, "part" indicates "part by weight".

[0070]

Example 1 (Synthesis of toner binder) In a reaction vessel equipped with a cooling pipe, a stirrer, and a nitrogen introducing pipe, 343 parts of a 2-mol adduct of bisphenol A ethylene oxide and 166 parts of isophthalic acid were added.
Parts and 2 parts of dibutyltin oxide, and
After reacting at 30 ° C. for 8 hours, and further reacting under reduced pressure of 10 to 15 mmHg for 5 hours, the mixture was cooled to 110 ° C., and 17 parts of isophorone diisocyanate was added in toluene to obtain 11 parts.
The reaction was performed at 0 ° C. for 5 hours, and then the solvent was removed to obtain a urethane-modified polyester (1) having a weight average molecular weight of 72,000. In the same manner as above, 570 parts of a bisphenol A ethylene oxide 2 mol adduct and 217 parts of terephthalic acid were polycondensed at 230 ° C. for 6 hours under normal pressure to give a peak molecular weight of 240
An unmodified polyester (a) having 0, a hydroxyl value of 51 and an acid value of 5 was obtained. 570 parts of bisphenol A ethylene oxide 2 mol adduct, terephthalic acid 2
17 parts were subjected to polycondensation under ordinary pressure at 230 ° C. for 6 hours.
After cooling to 80 ° C., 116 parts of trimellitic anhydride was added thereto and reacted at 180 ° C. and normal pressure for 2 hours to obtain a resin (D1) having negative chargeability. The AV of (D1) was 71. (D1) 100 parts were dissolved and mixed in 200 parts of ethyl acetate, and a diethanolamine part was added to convert the carboxyl group of (D1) into an amine salt. Urethane-modified polyester (1) 200 parts and unmodified polyester (a)
Acetic acid solution 3 of resin (D1) having 700 parts and negative chargeability
00 parts and 2,000 parts of ethyl acetate were mixed and dissolved to obtain a toner binder (1) in ethyl acetate. Part of the resultant was dried under reduced pressure to isolate the toner binder (1). Tg is 55
° C, Tη was 128 ° C, and TG 'was 140 ° C. (Preparation of toner) 240 parts of an ethyl acetate solution of the toner binder (1) and trimethylolpropane tribehenate (melting point: 58 ° C., melt viscosity: 24 cps) in a beaker
20 parts and 4 parts of cyanine blue KRO (manufactured by Sanyo Pigment Co., Ltd.) are added, and the mixture is mixed at 50 ° C. with a TK homomixer at 12000 rpm.
And uniformly dissolved and dispersed. In a beaker, 706 parts of ion-exchanged water and a 10% suspension of hydroxyapatite (Super Tight 10 manufactured by Nippon Chemical Industry Co., Ltd.) 294
And 0.2 part of sodium dodecylbenzenesulfonate were added and uniformly dissolved. Then, the temperature was raised to 50 ° C., and the above-mentioned toner material solution was charged while stirring at 12,000 rpm with a TK homomixer, followed by stirring for 10 minutes. Then, the mixture was transferred to a kolben equipped with a stir bar and a thermometer.
After removing the solvent by heating up, filtration, washing and drying,
Air classification was performed to obtain toner particles having a particle diameter d50 of 6 μm.
Next, 0.5 part of colloidal silica (Aerosil R972: manufactured by Nippon Aerosil) was mixed with 100 parts of the toner particles using a sample mill to obtain the toner (1) of the present invention. Table 1 shows the evaluation results.

Example 2 (Synthesis of prepolymer) In a reaction vessel equipped with a cooling pipe, a stirrer, a cooling pipe, and a nitrogen introducing pipe, 570 parts of a 2-mol adduct of bisphenol A ethylene oxide and isophthalic acid 2
17 parts and 2 parts of dibutyltin oxide were added, and reacted at 230 ° C. for 8 hours under normal pressure.
After reacting for 5 hours under reduced pressure, the mixture was cooled to 140 ° C., and 213 parts of isophorone diisocyanate was added.
The reaction was carried out for a time to obtain a prepolymer (1). (Synthesis of resin (D) having a negatively chargeable group) Bisphenol A ethylene oxide 2 mol adduct 57
0 parts, 217 parts of terephthalic acid, 12 parts of sulfoisophthalic acid
0 parts were polycondensed at 230 ° C. for 6 hours under normal pressure to obtain a resin (D1) having negative chargeability. The AV of (D1) was 78. (Synthesis of ketimine compound) 50 parts of isophoronediamine and 50 parts of methyl ethyl ketone were charged into a reaction vessel equipped with a stir bar and a thermometer, and reacted at 50 ° C for 5 hours. Then, 5 parts of diethanolamine was added, and the ketimine compound ( 1) was obtained. (Preparation of Toner) In a beaker, 174 parts of the prepolymer (1), 26 parts of the ketimine compound (1), 48 parts of ethyl acetate, and carbon black (MA manufactured by Mitsubishi Chemical Corporation)
100) 16 parts were added thereto, and the mixture was stirred at 60 ° C. with a TK homomixer at 12,000 rpm to be uniformly dissolved and dispersed. This is referred to as a resin liquid (1). 1000 parts of ion-exchanged water, 40 parts of polyvinyl alcohol (PVA-235 manufactured by Kuraray Co., Ltd.), and 0.3 part of sodium dodecylbenzenesulfonate were placed in a beaker and uniformly dissolved. Then 60
C., 200 parts of the resin liquid (1) was charged and stirred for 10 minutes while stirring at 12,000 rpm with a TK homomixer. Then, the mixed solution was transferred to a kolben equipped with a stir bar and a thermometer, and reacted at 60 ° C. for 10 hours. Then, the temperature was increased to remove the solvent, and the mixture was filtered, dried, and air-classified.
Toner particles having a particle size d50 of 7 μm were obtained. Next, colloidal silica (Aerosil R97) was added to 100 parts of the toner particles.
2: Nippon Aerosil Co., Ltd.) was mixed in a sample mill to obtain a toner (2) of the present invention. Table 1 shows the evaluation results.
Shown in

Example 3 (Synthesis of Toner Binder) A toner binder (3) was obtained in the same manner as in Example 1 except that the resin (D1) having a negatively chargeable group was not used as a toner binder component. (Synthesis of resin (D) having a negatively chargeable group) Xylene 6 was placed in an autoclave reactor equipped with a thermometer and a stirrer.
After adding 46 parts and replacing with nitrogen, a mixed solution of 746 parts of styrene, 140 parts of acrylonitrile, 130 parts of acrylic acid, 15.5 parts of di-tert-butyl peroxide and 118 parts of xylene was added dropwise at 170 ° C. for 3 hours. This temperature was maintained for 30 minutes. Subsequently, the solvent was removed to obtain a resin (D3) having a negatively chargeable group. The AV of (D1) was 101. 100 parts of (D3) was mixed and dissolved in 500 parts of methanol to obtain a methanol solution of (D3). (Preparation of toner) In a beaker, 240 parts of an ethyl acetate solution of the toner binder (3) and trimethylolpropane tribehenate (melting point: 58 ° C., melt viscosity: 24 cps)
20 parts and 4 parts of cyanine blue KRO (manufactured by Sanyo Pigment Co., Ltd.) are added, and the mixture is mixed at 50 ° C. with a TK homomixer at 12000 rpm.
And uniformly dissolved and dispersed. In a beaker, 706 parts of ion-exchanged water and a 10% suspension of hydroxyapatite (Super Tight 10 manufactured by Nippon Chemical Industry Co., Ltd.) 294
And 0.2 part of sodium dodecylbenzenesulfonate were added and uniformly dissolved. Then, the temperature was raised to 50 ° C., and the above-mentioned toner material solution was charged while stirring at 12,000 rpm with a TK homomixer, followed by stirring for 10 minutes. Then, the mixture was transferred to a kolben equipped with a stir bar and a thermometer.
After removing the solvent by heating up, filtration, washing and drying,
Air classification was performed to obtain toner particles having a particle diameter d50 of 6 μm.
Then, 500 parts of the methanol solution (D3) was mixed with 100 parts of the toner particles, stirred, and dried. Then, 0.5 part of colloidal silica (Aerosil R972: manufactured by Nippon Aerosil) was mixed with 100 parts of the toner particles using a sample mill, and the toner (1) of the present invention was obtained.
Table 1 shows the evaluation results. A toner (3) was obtained in the same manner as in Example 1 except that the toner binder (3) was used. Table 1 shows the evaluation results.

Comparative Example 1 A comparative toner binder (1) and a comparative toner (1) were obtained in the same manner as in Example 1 except that (D1) was not used as a resin having a negatively chargeable group as a toner binder component.
Table 1 shows the evaluation results.

Comparative Example 2 (Synthesis of Toner Binder) 354 parts of bisphenol A ethylene oxide 2 mol adduct and isophthalic acid 1
66 parts were subjected to polycondensation using 2 parts of dibutyltin oxide as a catalyst to obtain a comparative toner binder (2) having a weight average molecular weight of 8,000. Tg of the comparative toner binder (2) was 57 ° C., Tη was 136 ° C., and TG ′ was 133 ° C. (Preparation of Toner) In a beaker, 100 parts of the comparative toner binder (1), 200 parts of ethyl acetate solution, and 4 parts of cyanine blue KRO (manufactured by Sanyo Dye) were put into a beaker.
The mixture was stirred at 12000 rpm with a K-type homomixer and uniformly dissolved and dispersed. Next, a toner was prepared in the same manner as in Example 1 to obtain a comparative toner (2) having a particle diameter d50 of 6 μm. Table 1 shows the evaluation results. Evaluation Examples 1 to 3 and Comparative Evaluation Examples 1 and 2

[0075]

Table 1---------------------------------------------------------------------------------------------------------------- (60 min value) MFT HOT -------------------------------------------------------------------------------- Example 1 -13.7 -16. 2 135 ° C 230 ° C or more Example 2 -12.1 -15.1 130 ° C 230 ° C or more Example 3 -14.0 -16.5 135 ° C 230 ° C or more Comparative Example 1 7.8 15.9 135 ° C 230 ℃ or more Comparative Example 2 -10.1 -15.6 135 ℃ 170 ℃ −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− −

[Evaluation Method] Charge Amount 1 g of the toner and 24 g of a ferrite carrier for electrophotography (FL961-150, manufactured by Powdertech Co., Ltd.) were mixed for 3 minutes using a Turbuler shaker mixer, and the charge amount was measured as a blow-off charge amount. It measured using the measuring device (made by Toshiba Chemical). The mixture was further mixed for 57 minutes, and the charge amount was measured.
The charge amount after mixing for 3 minutes is referred to as a charge amount (3 minutes value), and the charge amount after mixing for 60 minutes is referred to as a charge amount (60 minutes value). Minimum fixing temperature (MFT) An unfixed image developed using a commercially available black-and-white copying machine (AR5030; manufactured by Sharp) is converted into a commercially available copying machine (SF8400A;
A fixing unit (made by Sharp Corporation) was modified and evaluated using a fixing machine with a variable fixing temperature. The minimum fixing temperature was the fixing roll temperature at which the residual ratio of the image density after rubbing the fixed image with a pad was 70% or more. Hot offset occurrence temperature (HOT) The fixing was evaluated in the same manner as in the above MFT, and the presence or absence of hot offset to the fixed image was visually evaluated. The temperature of the fixing roll at which the hot offset occurred was defined as the hot offset occurrence temperature.

[0077]

Since the negatively chargeable dry toner of the present invention has the following effects, it can be suitably used as a dry toner used in electrophotography, electrostatic recording, electrostatic printing and the like. 1. Excellent developability and transferability. 2. Excellent heat-resistant storage stability, and excellent both low-temperature fixability and hot offset resistance. 3. Since the color toner is excellent in glossiness and hot offset resistance, it is not necessary to apply oil to the fixing roll. 4. High transparency and excellent color tone when used as a color toner.

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) G03G 9/08 365 F term (reference) 2H005 AA01 AA06 AA15 AA21 AB03 CA08 CA13 CA14 CA18 CA21 DA02 DA05 DA06 DA10

Claims (5)

[Claims] 1. A negatively chargeable toner comprising a toner binder (A), a wax (B) and a colorant (C), wherein at least a part of the toner surface is covered with a resin (D) containing a negatively chargeable group. A negatively-chargeable dry toner characterized in that the toner is dry. 2. The toner according to claim 1, wherein the toner is a toner binder (A),
2. The toner according to claim 1, comprising particles formed by dispersing a toner material solution comprising a wax (B) and a colorant (C) in an aqueous medium. 3. The toner according to claim 1, wherein the toner binder (A) comprises a polyester modified with a urethane bond and / or a urea bond. 4. The toner according to claim 1, wherein said resin (D) has an acid value of 50 to 800. 5. The resin (D) has a carboxyl group, a sulfonic acid group, a phosphoric acid group, a sulfamic acid group,
The toner according to any one of claims 1 to 4, wherein the toner is at least one group selected from the group consisting of acetylacetonate groups.