JP2002229259A - Electrostatic charge image developing color toner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrostatic charge image developing yellow toner excellent in color reproducibility and transparency, exhibiting stable electrostatic charge behavior even in continuous printing, giving a good image of high image quality, having good fixability even under conditions of a low energy fixation such as a low temperature fixation or a short time fixation and excellent also in anti-offsetting property. SOLUTION: The electrostatic charge image developing color toner contains at least a binder resin and an isoindolinone-based organic dye and the binder resin in a polyester resin obtained by reacting monomer components including (A) a polybasic acid compound selected from among polybasic acids whose basicity is >=2 and/or acid anhydride and/or their lower alkyl esters and (B) an aliphatic polyhydric alcohol having >=2 OH groups.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[0002]

2. Description of the Related Art As a toner composition for obtaining a visible image by an electrophotographic method, a composition in which a black colorant such as carbon black is dispersed in a binder resin is often used. However, recently, a color toner in which a cyan pigment, a magenta pigment, a yellow pigment or other chromatic color pigments are dispersed in a binder has been used,
Full-color or mono-color copying machines and printers using these color toners have been developed.

The characteristics required for such a color toner include that the image after printing has a vivid color developing property, and that excellent transparency is exhibited in the color superposition in multicolor printing. Having clear color reproducibility without color turbidity, or using an overhead projector (hereinafter, referred to as
It is required to have color reproduction characteristics such as the ability to project clear colors without turbidity when projecting a color image obtained by transferring and fixing on a sheet onto a screen.

Further, as a system for fixing a toner image, a heat roll fixing system is widely and generally used, and good fixing properties and offset resistance at that time are also important characteristics required for a color toner. is there. In recent color copying machines or printers, the processing speed has been increased, so that the fixing temperature has become lower and the fixing time has become shorter. Furthermore, in order to simplify the machine structure and facilitate maintenance, an oil-less fixing system was developed, in which oil for preventing offset was not applied to the fixing heat roll, and the demand for suitable color toners increased. I have.

As described above, color toners are required to be fixed with lower energy and to have offset resistance in a temperature range as wide as possible. On the other hand, it is necessary to use a binder resin having a higher Tg in order to prevent the toner from melting and causing the particles to coagulate and harden during storage or transportation at a high temperature.

In general, the composition of a color toner comprises a binder resin and a colorant as main components and various other additives. As a binder resin for a color toner, a polyester resin is widely used. However,
With the polyester resins used so far, a polyester resin for a toner which sufficiently satisfies the fixing performance and the anti-offset performance in a wide temperature range from a low temperature region to a high temperature region, which is currently required, has not been obtained.

[0007] In addition, a two-component developing method using a toner and a carrier includes a developing method for a color copying machine and a printer.
There is a non-magnetic one-component developing method which does not use a carrier, but recently, with an increase in printing processing speed, an improvement in development characteristics of a color toner corresponding thereto has been required. For example, it is an improvement of image quality such as elimination of background stains at the time of high-speed printing, uniformity of solid images, reproducibility of fine lines, etc., and elimination of toner scattering into the machine and toner spilling from the developing device. .

Various techniques relating to color toners have been disclosed, but particularly for yellow color toners, in recent high-speed printing processes, they are fixed with low energy and have sufficient offset resistance. However, a toner capable of obtaining a high-quality print image without contaminating the inside of the machine has not been obtained.

[0009]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a yellow static toner which is excellent in color reproducibility and transparency, shows a stable charging behavior even in continuous printing, and provides good high-quality images. An object of the present invention is to provide a color toner for developing a charge image.

[0010] Another object of the present invention is to develop a yellow-based electrostatic image which exhibits good fixing properties even under low energy fixing conditions such as low-temperature fixing or short-time fixing and has excellent offset resistance. It is to provide a color toner.

[0011]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems, and as a result, a polyester resin obtained by reacting a yellow pigment having a specific structure with an aliphatic polyhydric alcohol. The present inventors have found that the above-mentioned problems can be solved by using a color toner using the present invention, and have completed the present invention.

That is, the present invention relates to a color toner for developing an electrostatic image containing at least a binder resin and an organic pigment, wherein the binder resin comprises (A) a dibasic or higher polybasic acid and / or an acid anhydride. And / or a polybasic acid compound selected from these lower alkyl esters (B) is a polyester resin obtained by reacting a monomer component containing a dihydric or higher aliphatic polyhydric alcohol, and the organic pigment is represented by the following < It is intended to provide a color toner for developing an electrostatic image, which is an organic pigment represented by the general formula 1>. <General formula 1>

Embedded image (Wherein, R represents a single bond, a propenylene group, an arylene group or an alkylene group having 1 to 3 carbon atoms, X represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 5 carbon atoms, and the above-mentioned propenylene group, arylene group and The alkylene group having 1 to 3 carbon atoms may have a substituent)

[0013]

Next, the present invention will be described in detail. Examples of the polybasic acid compound (A) selected from divalent or higher polybasic acids and / or acid anhydrides and / or lower alkyl esters thereof used in the present invention include, for example, phthalic anhydride, terephthalic acid, and isophthalic acid. , Orthophthalic acid, naphthalenedicarboxylic acid, adipic acid, maleic acid, maleic anhydride, fumaric acid, itaconic acid, citraconic acid, hexahydrophthalic anhydride, tetrahydrophthalic anhydride,
Cyclohexanedicarboxylic acid, succinic acid, malonic acid, glutaric acid, azelaic acid, dicarboxylic acids such as sebacic acid or derivatives or esters thereof, for example, trimellitic acid, trimellitic anhydride, pyromellitic acid, pyromellitic anhydride Examples include trifunctional or higher polycarboxylic acids such as acids, derivatives thereof, and esterified products thereof.

Examples of the dihydric or higher aliphatic polyhydric alcohol (B) include, for example, 1,4-cyclohexanedimethanol, ethylene glycol, diethylene glycol,
Triethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, butanediol, pentanediol, hexanediol, polyethylene glycol, polypropylene glycol, ethylene oxide-propylene oxide random copolymer diol, ethylene oxide-propylene oxide block copolymer Diol, ethylene oxide-
Diols such as tetrahydrofuran copolymer diol, polycaprolactone diol, and sorbitol,
1,2,3,6-hexanetetraol, 1,4-sorbitan, pentaerythritol, 1,2,4-butanetriol, 1,2,5-pentanetriol, glycerin, 2-methylpropanetriol, 2-methyl -1,
Examples include trifunctional or higher polyhydric alcohols such as 2,4-butanetriol, trimethylolethane, trimethylolpropane, and 1,3,5-trimethylolbenzene.

As the aliphatic alcohol component (B) which reacts with the carboxylic acid compound (A), neopentyl glycol diglycidyl ether, glycerin triglycidyl ether, trimethylol propane triglycidyl ether, trimethylol ethane tri Epoxy compounds such as glycidyl ether and pentaerythritol tetraglycidyl ether can also be used.

In the present invention, for example, an aromatic diol exemplified below can be used in combination with the aliphatic polyhydric alcohol. The aromatic diol that can be used in the present invention is polyoxyethylene- (2.0)
-2,2-bis (4-hydroxyphenyl) propane and its derivatives, polyoxypropylene- (2.0)-
2,2-bis (4-hydroxyphenyl) propane, polyoxypropylene- (2.2) -polyoxyethylene- (2.0) -2,2-bis (4-hydroxyphenyl) propane, polyoxypropylene- (6) -2,2
-Bis (4-hydroxyphenyl) propane, polyoxypropylene- (2.2) -2,2-bis (4-hydroxyphenyl) propane, polyoxypropylene-
(2.4) -2,2-bis (4-hydroxyphenyl)
Propane, polyoxypropylene- (3.3) -2,2
-Bis (4-hydroxyphenyl) propane and its derivatives.

Further, aromatic epoxy compounds such as bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, cresol novolak type epoxy resin and phenol novolak type epoxy resin may be used as necessary. it can.

In the present invention, the flexibility of the molecular chain in the polyester resin is improved by using the aliphatic polyhydric alcohol. For example, when the polyester resin is mixed with a carrier and used as a two-component developer, the carrier is received in the developing device. This has the effect of relieving stress, preventing the resin coating layer on the carrier surface from peeling off, and consequently has the effect of extending the life of the developer.

In the non-magnetic one-component developing device, a developing sleeve roll and a charging member such as a charging blade are brought into pressure contact with each other.
In this method, the toner is passed through a gap between the two, and the toner is charged at the moment when the toner passes through the gap. When the toner according to the present invention is used in this developing system apparatus, the flexibility of the molecular chain works effectively against the strong shear added when passing through the gap between the developing sleeve roll and the charging member, and the toner No particles are crushed or adhere to the blade.

Further, the softening of the polyester main chain improves the fixability at low temperatures. Further, for the purpose of improving the fixing / offset performance, adding a wax to the toner is a commonly used means. In the polyester resin using the aliphatic polyhydric alcohol in the present invention, particularly, wax is used. Has good compatibility, and the fixing performance at low temperatures and the offset resistance are further improved.

Therefore, it is necessary to use the above aromatic diol within a range that does not impair the gist of the present invention. The amount of the aromatic diol used is desirably less than 5 mol% based on the total alcohol components. It is more preferably at most 3 mol%.

As the carboxylic acid component used in the present invention, naphthalenedicarboxylic acid and / or dimethylnaphthalate, diethylnaphthalate, dibutylnaphthalate and the like as lower alkyl esters thereof are more preferably used. It is necessary to use these compounds in an amount of 5 mol% or more of the total acid component, more preferably 10 mol% or more.

A monomer containing a naphthalene ring structure is effective in increasing the Tg of the resin, and improves the heat-resistant cohesion of the resin. Particularly in a system mainly using a soft aliphatic diol as an alcohol component, a decrease in Tg of the resin can be suppressed, and a low-temperature fixability by using the aliphatic diol and a heat cohesion property by naphthalenedicarboxylic acid can be obtained. A resin having both of them can be obtained.

Further, as the polyhydric alcohol component, 1,
Preferably, 4-cyclohexanedimethanol is used. The preferred amount is at least 5 mol% of the total alcohol component. It is more preferable to use 10 mol% or more.
By using 1,4-cyclohexanedimethanol, the Tg of the resin can be increased, and the heat-resistant coagulation property is further improved. As the polyester resin used in the present invention,
It is preferable that the resin uses both naphthalenedicarboxylic acid and 1,4-cyclohexanedimethanol.

The polyester resin in the present invention can be obtained, for example, by conducting a dehydration-condensation reaction or a transesterification reaction using the above-mentioned raw material components (A) and (B) in the presence of a catalyst. The reaction temperature and reaction time at this time are
Although not particularly limited, usually 150 to 300 ° C.
For 2 to 24 hours.

As a catalyst for carrying out the above reaction, for example, tetrabutyl titanate, zinc oxide, stannous oxide, dibutyltin oxide, dibutyltin dilaurate, p-toluenesulfonic acid and the like can be appropriately used.

The polyester resin used in the present invention preferably has a glass transition temperature (Tg) of 50 ° C. or higher, and particularly preferably has a Tg of 55 ° C. or higher. When the Tg is 50 ° C. or lower, a blocking phenomenon (thermal aggregation) tends to occur when the toner is stored, transported, or exposed to a high temperature inside a developing device of a machine.

Further, the softening point of the polyester resin used in the present invention is 90 ° C. or higher, especially 90 ° C. to 1 ° C.
It is preferably in the range of 80 ° C, more preferably 95%.
C. to 160.degree. When the softening point is lower than 90 ° C., the toner is liable to cause agglomeration, and when storing or printing, trouble tends to occur.

Further, as a full-color toner,
When color reproducibility at the time of color superposition or transparency when fixed on an OHP sheet is required, the softening point of the polyester resin is preferably in the range of 90 ° C to 130 ° C, more preferably , 95 ° C to 120 ° C.

The acid value of the polyester resin of the present invention is preferably 20 mgKOH / g or less from the viewpoint of improving the moisture resistance of the toner.

In the present invention, an organic pigment represented by the general formula 1 is used. By using a pigment having this structure, a yellow organic pigment usually used in a conventional toner, for example, an azo C.I. I. Pigment Yellow 17 and non-azo benzimidazolone C.I. I. Pigmen
While maintaining color reproducibility and transparency as compared with t Yellow 180 or the like, it shows a stable charging behavior during continuous printing, and as a result, a good high-quality image can be obtained. <General formula 1>

[0032]

Embedded image (Wherein, R represents a single bond, a propenylene group, an arylene group or an alkylene group having 1 to 3 carbon atoms, X represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 5 carbon atoms, and the above-mentioned propenylene group, arylene group and The alkylene group having 1 to 3 carbon atoms may have a substituent)

Particularly, in a toner using an organic pigment represented by the general formula (1) with a polyester resin using an aliphatic alcohol in the present invention as a binder, this is used in a developing device of a non-magnetic one-component developing system. In this case, the initial charge amount can be reached instantaneously when passing through the gap between the developing sleeve and the charging member, and an appropriate charge amount can be maintained even during long-time printing. Of the developer can be obtained.

The charge amount of the toner used in the developing device of the non-magnetic one-component developing system is evaluated as a charge amount immediately after the toner passes between the developing sleeve and a charging member such as a blade pressed against the developing sleeve. . There are various measurement methods.For example, the toner adhering to the developing sleeve is sucked through a Faraday gauge having a filter layer on the outlet side, and charged by the weight and charge amount of the toner trapped in the Faraday gauge. There is a method of calculating the quantity (Q / M). There is also a method of measuring the surface potential of the developing sleeve to determine the charge amount of the toner. The toner of the present invention shows a desired charge amount from the initial stage of printing, and the charge amount varies little even in long-time printing.

Further, since the organic pigment of the <general formula 1> used in the present invention does not have a benzidine skeleton in the molecular structure, a decomposition product is regarded as a safety and health problem like a disazo pigment. Nothing.

The pigment represented by the general formula 1 is an isoindolinone-based yellow pigment, and specific examples thereof include C.I.
I. Pigment Yellow 110 (for example, manufactured by Dainippon Ink and Chemicals, Inc., trade name: Fastgen Yellow GRO), C.I. I. Pigment Yellow
w109 (for example, Ciba-Geigy, trade name: Yellow 2RLT), C.I. I. Pigment Yellow
137 (for example, manufactured by Dainippon Ink and Chemicals, Inc., trade name: Super Yellow GROH), C.I. I. Pigme
nt Yellow 173 (for example, Ciba Geigy, trade name: Sandrin Yellow 6GL) and the like, and these can be used alone or in combination of two or more.

Among the above, C.I. I. Pigment
Yellow 110, C.I. I. Pigment Ye
llow109 is preferred. Particularly preferred are C.I. I.
Pigment Yellow 110. Each structure is as follows.

[0038]

Embedded image <C. I. Pigment Yellow109>

[0039]

Embedded image <C. I. Pigment Yellow110>

The amount of the colorant used in the present invention is preferably in the range of 1 to 20 parts by weight, more preferably 2 to 15 parts by weight, particularly preferably 2 to 10 parts by weight per 100 parts by weight of the binder resin. preferable.

In the present invention, in addition to the organic pigment described in <General Formula 1>, other colorants for adjusting the hue can be used. Examples of such a coloring agent include well-known coloring agents. For example, a phthalocyanine C.I. I. Pigment Blue 15-
3. Indanthrone C.I. I. Pigment Bl
ue 60 and the like are quinacridone C.I. I. Pigment Red 122, an azo C.I. I. Pigment Red 22, C.I. I. Pig
Ment Red 48: 1, C.I. I. Pigment
Red 48: 3, C.I. I. Pigment Red 5
7: 1 and the like, and azo-based C.I. I. P
pigment yellow 12, C.I. I. Pigme
nt Yellow 13, C.I. I. Pigment Y
yellow 14, C.I. I. Pigment Yellow
w 17, C.I. I. Pigment Yellow 9
7, C.I. I. Pigment Yellow 155, a benzimidazolone C.I. I. Pigment Yel
low 151, C.I. I. Pigment Yellow
154, C.I. I. Pigment Yellow 18
0, etc.

The above-mentioned pigments can be used in combination with the yellow pigment of the general formula 1 used in the present invention as long as the object of the present invention is not impaired. For example, a green toner can be obtained by combining with a phthalocyanine pigment, and a light-color toner can be obtained by combining with a quinacridone pigment. When the pigment of the <general formula 1> is used in combination with another pigment, the amount of the pigment of the <general formula 1> is preferably at least 40% by weight, more preferably at least 50% by weight. It is more preferably at least 60% by weight.

In the present invention, a charge control agent can be used if necessary. For example, a nigrosine dye, a triphenylmethane dye, a quaternary ammonium salt, a resin containing a quaternary ammonium group and / or an amino group as a positive charge control agent, a trimethylethane dye, a metal of salicylic acid as a negative charge control agent Complex salts, metal complex salts of benzylic acid, copper phthalocyanine, perylene, quinacridone, azo pigments, metal complex salt azo dyes, heavy metal-containing acid dyes such as azochrome complexes, calixarene-type phenol condensates, cyclic polysaccharides, carboxyl groups And / or a resin containing a sulfonyl group.

In the present invention, it is particularly preferable to use a colorless charge control agent. As the negative charge control agent, "Bontron E-84" manufactured by Orient Chemical Co. as a metal complex compound of salicylic acid, TP-302 and TP-4 having a quaternary ammonium salt structure as positive charge control agents
15, TP-610; (Hodogaya Chemical), Bontron P
-51; (Orient Chemical), Copy Charge PSY
(Clariant Japan) and the like are preferably used. Examples of the positively chargeable resin-type charge control agent containing a quaternary ammonium group and / or an amino group include “FCA-20”.
1-PS "(Fujikura Kasei Co., Ltd.) and the like.

Above all, as the charge controlling agent which can be particularly preferably used in the present invention, there are a compound represented by the following <General formula 2> and a compound represented by the <General formula 3>. <General formula 2>

[0046]

Embedded image Wherein R ₁ is a quaternary carbon, methine, methylene,
N may include a heteroatom of N, S, O, or P; Y represents a cyclic structure connected by a saturated bond or an unsaturated bond;
₂ and R ₃ are each independently an alkyl group, an alkenyl group, an alkoxy group, an aryl group or an aryloxy group which may have a substituent, an aralkyl group or an aralkyloxy group, a halogen group, hydrogen, a hydroxyl group, a substituent Which may have an amino group, a carboxyl group, a carbonyl group, a nitro group,
R ₄ represents hydrogen or an alkyl group; t is an integer of 0 to 1 to 12; m is an integer of 1 to 20; n is an integer of 0 to 1 to 20; Is an integer from 0 to 1 to 4, p is an integer from 0 to 1 to 4, q is an integer from 0 to 1 to 3, r is an integer from 1 to 20, and s is 0 or an integer from 1 to 20. )

<General formula 3>

[0048]

Embedded image (Wherein, R ₁ and R ₄ represent a hydrogen atom, an alkyl group, a substituted or unsubstituted aromatic ring (including a condensed ring), and R ₂ and R ₃ represent a substituted or unsubstituted aromatic ring (including a condensed ring) ), And M is one kind of 3 selected from B, Al, Fe, Ti, Co, and Cr.
Represents a valent metal, and X ⁺ represents a cation)

Specific examples of the compound represented by the general formula 2 include the following <Charge Control Agent 1> to <Charge Control Agent 3>.

<Charge control agent 1>

[0051]

Embedded image

<Charge control agent 2>

[0053]

Embedded image

<Charge control agent 3>

[0055]

Embedded image

Further, specific examples of the compound represented by the general formula 3 include the following <Charge control agent 4> and <Charge control agent 5>.
There is.

<Charge Control Agent 4>

[0058]

Embedded image

<Charge Control Agent 5>

[0060]

Embedded image

The above-mentioned charge control agents may be used alone or in combination.
Good charging performance can be obtained by adding 15 parts by weight, preferably 0.5 to 5 parts by weight.

In the toner of the present invention, various known waxes such as polypropylene wax, polyethylene wax, polyamide wax, Fischer-Tropsch wax and the like can be appropriately used as a releasing agent. It is preferable to use a wax containing an ester compound and / or an aliphatic alcohol compound as a release agent.

Among the waxes containing higher fatty acid ester compounds and / or aliphatic alcohol compounds, natural waxes such as carnauba wax, montan ester wax, rice wax, scale insect wax and / or synthetic ester waxes are particularly preferred. . As the synthetic ester wax, pentaerythritol tetrabehenate is particularly preferred.

These waxes show the best dispersibility in the polyester resin having the structure according to the present invention, and the fixability and the offset resistance are remarkably improved. Further, even when these waxes are used for printing many sheets for a long time, for example, when used as a non-magnetic one-component developing toner, the toner is stably charged without adhering to a charging member pressed against a developing sleeve. , And high-quality and high-definition images can be printed without image defects or background contamination. Further, when a color toner is used together with the coloring agent of the general formula 1 of the present invention, a color toner excellent in transparency as compared with a hydrocarbon wax such as a polypropylene wax can be obtained. The color toner having such characteristics is transparent and needs to have a clear projected image.
It is suitable for printing on a P sheet and for printing an intermediate color with good color reproducibility by printing two or more colors in a superimposed manner.

As the carnauba wax, it is preferable to use carbauba wax that has been freed from fatty acids and whose free fatty acids have been removed by purification. The acid value of the free fatty acid-type carnauba wax is preferably 3 or less, more preferably 2 or less. The free fatty acid type carnauba wax becomes finer crystals than the conventional carnauba wax, and the dispersibility in the polyester resin is improved. The montan-based ester wax is refined from a mineral, and becomes fine crystals like the carnauba wax by the purification, so that the dispersibility in the polyester resin is improved. The acid value of the montan ester wax is particularly preferably 30 or less. Rice wax is obtained by refining rice bran wax, and preferably has an acid value of 13 or less. The scale insect wax is the scale insect (also known as the larva)
The waxy components secreted by the larvae are, for example, dissolved in boiling water,
It can be obtained by cooling and solidifying the upper layer after separation, or by repeating the same. The scale insect wax purified by such a means is white in a solid state, has an extremely sharp melting point, and is suitable as a toner wax in the present invention. The acid value is reduced to 10 or less due to purification, and is preferably 5 or less for toner.

The above waxes may be used alone or in combination.
A good fixing offset performance can be obtained by adding 1 part by weight, preferably 1 to 5 parts by weight. When the amount is less than 0.3 parts by weight, the offset resistance is impaired, and when the amount is more than 15 parts by weight, the fluidity of the toner deteriorates, and in the two-component developing system, a spent carrier is generated by adhering to the carrier surface, It adversely affects the charging characteristics of the toner, and adheres to the layer thickness regulating member pressed against the developing roll in the non-magnetic one-component developing system.

The production method for obtaining the toner of the present invention is as follows.
It can be obtained by any known and commonly used means. For example, after melt-kneading a resin, a colorant, a wax, and various additives as necessary at a temperature equal to or higher than the melting point (softening point) of the resin, pulverizing,
It can be obtained by classification. The colorant is flushed in advance so that it is evenly dispersed in the resin.
Alternatively, a master batch melt-kneaded with a resin at a high concentration may be used.

Specifically, for example, the above-mentioned resin, colorant and wax are mixed as essential components by a kneading means such as a two-roll, three-roll, pressure kneader or a twin-screw extruder. At this time, the colorant may be uniformly dispersed in the resin, and the conditions for the melt-kneading are not particularly limited, but are generally at 80 to 180 ° C. for 10 minutes to 2 hours. The kneaded material is usually cooled by a cooling belt, a roller, or the like, but since the dispersion state of the release agent changes depending on the cooling conditions, the cooling conditions can be set so as to obtain a desired dispersion state.

Further, if necessary, coarse pulverization is performed for the purpose of reducing the load in the fine pulverization step and improving the pulverization efficiency. The apparatus and conditions used for the coarse pulverization are not particularly limited, but the coarse pulverization is generally performed using a rotoplex, a pulperizer, or the like to a particle size of 3 mm mesh pass or less.

Next, a method of finely pulverizing with a mechanical pulverizer such as a turbo mill or a kryptron, or an air pulverizer such as a spiral jet mill, a counter jet mill, or an impinging plate type jet mill, and classifying with a wind classifier or the like is used. No. Fine grinding and classification equipment, conditions are the desired particle size,
What is necessary is just to select and set it so that it may become a particle size distribution and a particle shape.

In the present invention, various additives (referred to as external additives) can be used for modifying the surface of the toner base such as improving the fluidity of the toner and improving the charging characteristics. Examples of the external additives that can be used in the present invention include inorganic fine powders such as silicon dioxide, titanium oxide, aluminum oxide, cerium oxide, zinc oxide, tin oxide, and zirconium oxide, and silicone oils and silane coupling agents. Surface-treated with a hydrophobizing agent, such as polystyrene, acrylic, styrene acrylic, polyester, polyolefin, cellulose, polyurethane, benzoguanamine, melamine, nylon, silicone, phenol, vinylidene fluoride, and Teflon (registered trademark). Are used.

Among these, silicon dioxide (silica) whose surface is hydrophobized with various polyorganosiloxanes, hexamethylene disilazane, a silane coupling agent or the like can be particularly preferably used. As such,
For example, there is one that is commercially available under the following trade names.

AEROSIL R972, R974, R202, R805, R812, RX200, RY200, R809, RX50, RA200HS, RA200H (Nippon Aerosil Co., Ltd.) WACKER HDK H2000, H1018, H2050EP HDK H3050EP, HVK2150 [Waker Chemical Yeast )] Nipsil SS-10, SS-15, SS-20, SS-50, SS-60, SS-100, SS-50B, SS-50F, SS-10F, SS-40, SS-70, SS-72F [Nippon Silica Kogyo Co., Ltd.] CABOSIL TG820F, TS-530, TS-720 [Cabot Specialty Chemicals, Inc.] The particle size of the external additive is one of the diameter of the colored particles as the base toner.
/ 3 or less, particularly preferably 1/10
It is as follows. Further, these external additives may be used in combination of two or more kinds having different average particle diameters.

In particular, in the case of a non-magnetic one-component developing toner, by using both a large particle size toner and a small particle size toner, the toner fluidity and development durability are improved, and the toner is fixed to the blade of the developing machine. In addition, it is preferable because it can prevent fogging and long-term stability of charging during running.

The proportion of the external additive is 0.05 to 5% by weight, preferably 0.1 to 5% by weight, based on 100 parts by weight of the base toner.
3% by weight.

As a method for externally adding the silica to the toner particles, for example, a Henschel mixer, which is a usual powder mixer, or a so-called surface modifier such as a hybridizer can be used. In this external addition process, silica may be attached to the surface of the toner particles, or a part of the silica may be embedded in the toner particles.

As a developing method using the toner of the present invention as a non-magnetic one-component developing toner, the toner of the present invention is carried on a developing sleeve without being mixed with a carrier, and the toner is used as a photosensitive member having an electrostatic latent image. There is a contact type non-magnetic one-component developing method in which development is performed by contacting with a drum.

When the toner of the present invention is used as a non-magnetic one-component developing toner, the toner is frictionally charged by passing between the developing sleeve and the charging member pressed against the developing sleeve. The present invention can be particularly effectively used in a contact type non-magnetic one-component developing device for developing a formed electrostatic latent image.

When the toner of the present invention is used as a non-magnetic one-component developing toner, the material of the charging member of the developing device is not particularly limited as long as it is under normal use conditions. For example, aluminum, stainless steel, urethane rubber,
A developing sleeve made of silicon rubber, aluminum, stainless steel, duralumin, copper, or a layer thickness regulating member in which urethane rubber or silicon rubber is bonded thereto can be suitably used.

A developing method suitable for the toner of the present invention to exhibit its effects is a case where one of the developing sleeve and the charging member is made of a metal such as aluminum or stainless steel. Sleeve / charging member) is a combination of a urethane rubber or silicone rubber developing sleeve and a stainless steel charging member,
Alternatively, it is a combination of a developing sleeve made of stainless steel and a charging member made of urethane rubber or silicon rubber.

When the electrostatic image developing toner of the present invention is used in a two-component developing system, the following carriers can be used.

As the core agent of the carrier, iron powder, magnetite, ferrite and the like used in a usual two-component developing system can be used. Among them, since the true specific gravity is low, the resistance is high, the environmental stability is excellent, and the sphere is easily formed. Ferrite or magnetite having good fluidity is preferably used. The shape of the core agent can be used without any particular problem, such as spherical or amorphous.
The average particle size is generally 10 to 500 μm, but is preferably 30 to 80 μm for printing a high-resolution image.

Examples of the coating resin for covering these core agents include polyethylene, polypropylene, polystyrene, polyacrylonitrile, polyvinyl acetate, polyvinyl alcohol, polyvinyl butyral, polyvinyl chloride, polyvinyl carbazole, polyvinyl ether polyvinyl ketone, and vinyl chloride. / Vinyl acetate copolymer, styrene / acrylic copolymer, straight silicone resin comprising organosiloxane bond or its modified product, fluororesin, (meth) acrylic resin, polyester, polyurethane, polycarbonate, phenolic resin, amino resin, melamine resin , Benzoguanamine resin, urea resin, amide resin, epoxy resin, acrylic polyol resin and the like can be used. Among these,
In particular, silicone resins, fluororesins, and (meth) acrylic resins are excellent in charge stability, coating strength, and the like, and can be more preferably used. That is, the resin-coated carrier used in the present invention is:
It is preferable that the magnetic carrier is a resin-coated magnetic carrier that uses ferrite or magnetite as a core agent and is coated with at least one resin selected from silicone resins, fluororesins, and (meth) acrylic resins.

[0084]

The present invention will be described below in more detail with reference to Examples and Comparative Examples. In the following, numerical values in the composition table represent "parts by weight". An example of the synthesis of the binder resin used in preparing the toner first is shown below.

(Synthesis Example 1) Naphthalenedicarboxylic acid 130 parts by weight Terephthalic acid 216 parts by weight Cyclohexanedimethanol 72 parts by weight Neopentyl glycol 104 parts by weight Ethylene glycol 31 parts by weight

The above-mentioned raw materials were placed in a glass 2-liter four-necked flask, fitted with a thermometer, a stirring rod and a nitrogen inlet tube, and heated in an electric heating mantle heater under a normal pressure nitrogen stream.
After reacting at 40 ° C for 10 hours, the pressure was sequentially reduced to 1330 Pa
The reaction was continued at (10 mmHg). The reaction is ASTM
The reaction was followed by a softening point according to E28-517, and the reaction was terminated when the softening point reached 105 ° C.

The resulting polymer was a colorless solid, having an acid value of 12, a glass transition temperature of 70 ° C.
The softening point was 106 ° C.

A binder resin was produced according to the formulation shown in Table 1 by the method according to Synthesis Example 1. The physical properties of the synthesized resin are shown in Table 1.

[0089]

[Table 1]

The indications in the table are as follows. • NDC: naphthalenedicarboxylic acid • TPA: terephthalic acid • IPA: isophthalic acid • BPA (2.2) PO: 2.2 mol bisphenol A propylene oxide adduct • NPG: neopentyl glycol • EG: ethylene glycol • CHDM: 1 , 4-cyclohexanedimethanol

Example 1 <Production of Toner> 94 parts by weight of resin of Synthesis Example 1 I. Pigment Yellow 110 3 parts by weight (Fastgen Yellow GRO, manufactured by Dainippon Ink and Chemicals, Inc.) 1 part by weight of compound <Charge Control Agent 1> 1 part by weight of purified carnauba wax 12 parts by weight (acid value 5, manufactured by Ceralica NODA) are mixed with a Henschel mixer and kneaded with a twin-screw kneader. The kneaded product thus obtained was pulverized and classified to obtain a “toner base material” having a volume average particle diameter of 7.5 μm.

-100 parts by weight of the above "toner raw material"-0.5 parts by weight of silica "NAX50" manufactured by Nippon Aerosil (average particle diameter of primary particles: 30 nm)-0.5 parts by weight of silica "RY200" manufactured by Nippon Aerosil The average particle size of the primary particles (12 nm) was mixed with a Henschel mixer and then sieved to obtain the toner of Example 1.

Thereafter, toners of Examples 2 to 6 and Comparative Examples 1 to 3 were produced in the same manner as in Example 1 with the composition shown in Table 2.

[0094]

[Table 2]

The indications in the table are as follows. Pig. Y110: CI Pigment Yellow 110 “Fast Gen Yellow GRO, manufactured by Dainippon Ink and Chemicals, Inc.” • TYHG: Toner Yellow HG VP2155 “Clariant Japan” • KET B.111: KET Blue 111, “Dainippon Ink and Chemicals”・ Carnauba wax; Carnauba wax No. 1 (acid value 5), manufactured by Cera Rica NODA Co., Ltd. 1 (acid value 2) manufactured by Cera Rica NODA Co., Ltd.-PP WAX; polypropylene wax manufactured by Viscol 550P "Sanyo Kasei"-wax 4; pentaerythritol tetrabehenate ester-PETB; pentaerythritol tetrabehenate ester-E-84; Zinc salicylate complex (Orient Chemical)

<Fixing Offset Test by Heat Roll Fixing> An unfixed image sample of A-4 paper size was prepared using a test machine modified from a commercially available non-magnetic one-component developing type printer, and a heat roll fixing unit having the following specifications was used. The fixing start temperature and the presence or absence of an offset phenomenon were confirmed under the following test conditions using In order to measure the fixing start temperature, an image density remaining ratio calculated by the following equation was obtained.

Image density residual ratio = image density after fastness test / image density before left test * Image density was measured by Macbeth image densitometer RD-918. * The image density after fastness test is the image density after rubbing the fixed image using a Gakushin type friction fastness tester (load: 200 g, rubbing operation: 5 strokes). Image density remaining ratio
At 80% or more, there was no practical problem, and the lowest temperature was the fixing start temperature.

The offset start temperature was a temperature at which the offset phenomenon was visually observed when the fixed image sample was observed. The results are shown in Table-3.

<Print Durability Test; Image Density of Printed Material, Background Stain, Contamination inside Machine, Charge Amount> (1) Image Density of Printed Product, Background Stain The toner obtained in each of Examples and Comparative Examples was filled in
Continuous printing was performed on the sheets, and the state where the toner layer on the developing sleeve was uniform and no defect was generated was determined as “○”, and the case where uneven portions such as stripes were generated was determined as “x”. The image density (solid image of 2 cm square) and background stain of the printed matter were measured by Macbeth densitometer RD-918. The background stain was obtained by subtracting the density of the white paper before printing from the density of the white background after printing. When the difference was less than 0.01, it was evaluated as ○, when it was less than 0.01 to 0.03, it was evaluated as Δ, and when it was 0.03 or more, it was evaluated as ×. The results are shown in Table-3. (2) Dirt inside the machine After printing 10000 sheets, spilling from the surface of the developing sleeve or from the gap where the developing sleeve and the charging member are in contact with each other, or when there is almost no dirt due to scattered toner. The result was indicated by Δ, and the case of severe stains was indicated by X. (3) Charge Along with the above-mentioned printing test, a suction type small charge measuring device (Model 210HS) manufactured by Trek, which measures the charge by taking the toner on the developing sleeve into a Faraday gauge by a suction nozzle. -2A), the charge amount of the toner was measured.

<Heat Resistance Coagulation Test> Toner 10 before mixing with carrier in 100 cc cylindrical polycup without lid
g was put in a thermostat set at 65 ° C. 2
After a lapse of 4 hours, the polycup was taken out, and the toner inside was discharged by slowly tilting the polycup on a horizontal table. At that time, there is no aggregation due to fusion of the toner particles at all, and the state where the toner powder spreads on the table is ○, the state where there is a little aggregation The state in which the shape of the polycup as it was in the polycup while being kept almost was evaluated as x. The results are shown in Table-3.

<Evaluation of OHP Sharpness> An unfixed image was formed on an OHP sheet by using a commercially available non-magnetic one-component developing system printer, and the unfixed image was fixed by a separately prepared fixing tester. . As a fixing tester, a heat roll fixing device with a built-in temperature sensor was used.
Performed at 0 ° C. The heat roll (upper) is made of Teflon (registered trademark of DuPont), the lower roll is made of HTV silicon,
The fixing was performed at a load of 7 kg / 350 mm, a nip width of 4 mm, and a sheet passing speed of 50 mm / sec.

The OHP sheet prepared according to the above procedure was projected on a white screen by an overhead projector, and the sharpness was evaluated. The evaluation was made by visual observation, and a clear and transparent good projected image was evaluated as ○, and a turbid blackish projected image was evaluated as ×. Table 3 shows the results.
It was shown to.

[0103]

[Table 3]

The indications in the table are as follows. * “Charge amount”: μC / g

(Example 7) 4 parts of the toner of Example 1 and a carrier manufactured by Powder Tech Co., Ltd. "Ferrite carrier F-15"
The developer was adjusted by friction mixing 96 parts of “0”. This developer was put into a developing device of a copying machine "BD-3504" manufactured by Toshiba Corporation, and a continuous printing test of 50,000 sheets was performed. as a result,
There was no change in image density between the initial printing and after continuous printing, and a printed matter of good image quality without image defects or background smear was obtained. Also,
Continuous printing was performed without contaminating the inside of the machine with scattering toner and the like.

(Comparative Example 4) 4 parts of the toner of Comparative Example 2 and a carrier "Ferrite carrier F-15" manufactured by Powder Tech Co., Ltd.
The developer was adjusted by friction mixing 96 parts of “0”. This developer was used in the same manner as in Example 7 to produce a copier “BD-350” manufactured by Toshiba Corporation.
4 "and a continuous printing test of 50,000 sheets was conducted. As a result, the image density of the printed matter in the latter half of continuous printing was lower than that in the initial stage of printing, and the printed matter was of low image quality in which background smear was observed. Furthermore, the inside of the machine was contaminated with scattered toner and the like.

(Comparative Example 5) 4 parts of the toner of Comparative Example 3 and a carrier "Ferrite carrier F-15" manufactured by Powder Tech Co., Ltd.
The developer was adjusted by friction mixing 96 parts of “0”. This developer was used in the same manner as in Example 7 to produce a copier “BD-350” manufactured by Toshiba Corporation.
4 "and a continuous printing test of 50,000 sheets was conducted. As a result, the image density of the printed matter in the latter half of continuous printing was lower than that in the initial stage of printing, and the printed matter was of low image quality in which background smear was observed. Furthermore, the inside of the machine was contaminated with scattered toner and the like.

From the above results, it can be seen that the toner of the comparative example has much toner spilled and scattered from the developing device, and contaminates the inside of the machine. Further, in the toner of Comparative Example 3 using a polyester using only an aromatic diol as an alcohol component, Example 1 in which the composition other than the resin was the same.
The fixing temperature is higher than that of the toner. Further, in the printing durability test, the toner layer on the developing sleeve after printing 10,000 sheets was non-uniform, and streak-like defects occurred in the circumferential direction of the developing sleeve. Further, in the layer thickness regulating member pressed against the developing sleeve, a fixed substance was observed at a portion in contact with the developing sleeve. Further, as the number of prints increased, the image density decreased, streak-like stains were observed in the developing direction, and background stains increased, resulting in a print image with poor print quality.

[0109]

The toner of the present invention is excellent in low-temperature fixing and offset resistance, and exhibits excellent heat characteristics in heat roll fixing under low energy conditions during high-speed printing. In addition, it is possible to obtain a long-life developer exhibiting a stable charging behavior even during continuous printing and capable of obtaining a good image without fluctuation in image density. Further, the toner of the present invention is excellent in transparency and shows good fixing / offset characteristics in a wide temperature range, and thus is suitable as a color toner of an oilless heat roll fixing system.

Claims (5)

[Claims] 1. A color toner for developing an electrostatic image containing at least a binder resin and an organic pigment, wherein the binder resin comprises: (A) a dibasic or higher polybasic acid and / or
A polybasic acid compound (B) selected from acid anhydrides and / or lower alkyl esters thereof; a polyester resin obtained by reacting a monomer component containing a dihydric or higher aliphatic polyhydric alcohol; The pigment is as follows <General formula 1
<1> A color toner for developing an electrostatic image, characterized by being an organic pigment. <General formula 1> (Wherein, R represents a single bond, a propenylene group, an arylene group or an alkylene group having 1 to 3 carbon atoms, X represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 5 carbon atoms, and the propenylene group, the arylene group and The alkylene group having 1 to 3 carbon atoms may have a substituent) 2. The polybasic acid compound contains naphthalenedicarboxylic acid and / or an acid anhydride and / or a lower alkyl ester thereof in a ratio of 5 mol% or more based on the total acid components. 2. The color toner for developing an electrostatic image according to 1. 3. The aliphatic polyhydric alcohol comprises 1,4-cyclohexanedimethanol in an amount of 5 to all alcohol components.
2. The composition of claim 1, wherein the content is at least mol%.
Or a color toner for developing an electrostatic image according to 2. 4. A charge control agent represented by the following <general formula 2>
The color toner for developing an electrostatic image according to any one of claims 1, 2 and 3, further comprising a compound represented by the following formula (3). <General formula 2> Wherein R ₁ is a quaternary carbon, methine, methylene,
N may include a heteroatom of N, S, O, or P; Y represents a cyclic structure connected by a saturated bond or an unsaturated bond;
₂ and R ₃ are each independently an alkyl group, an alkenyl group, an alkoxy group, an aryl group or an aryloxy group which may have a substituent, an aralkyl group or an aralkyloxy group, a halogen group, hydrogen, a hydroxyl group, a substituent Which may have an amino group, a carboxyl group, a carbonyl group, a nitro group,
R ₄ represents hydrogen or an alkyl group; t is an integer of 0 to 1 to 12; m is an integer of 1 to 20; n is an integer of 0 to 1 to 20; Is an integer of 0 to 1 to 4, p is an integer of 0 to 1 to 4, q is an integer of 0 to 1 to 3, r is an integer of 1 to 20, s is 0 or an integer of 1 to 20. <General formula 3> (Wherein, R ₁ and R ₄ represent a hydrogen atom, an alkyl group, a substituted or unsubstituted aromatic ring (including a condensed ring), and R ₂ and R ₃ represent a substituted or unsubstituted aromatic ring (including a condensed ring) ), And M is one kind of 3 selected from B, Al, Fe, Ti, Co, and Cr.
Represents a valent metal, and X ⁺ represents a cation) 5. The method according to claim 1, further comprising a wax containing a higher fatty acid ester compound and / or an aliphatic alcohol compound as a releasing agent.
The color toner for developing an electrostatic image according to any one of the above.