JPH10221890A - Electrostatic charge controlling agent for developing electrostatic charge image, toner and electric charge imparting material using same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a toner excellent is stability of a charged state and excellent also in other characteristics required by a toner, that is, moisture, light and heat resistances, etc., without using a metal-contg. electrostatic charge controlling agent by using a compd. having a specified structure as an electrostatic charge controlling agent. SOLUTION: This electrostatic charge controlling agent is a compd. represented by the formula Ar<1> -COO-Ar<2> (I) or Ar<3> -(X-Ar<4> )n (II). In the formula I, Ar<1> is a residue of an arom. ring optionally substd. by one or more kinds of groups selected from among optionally substd. alkyl, alkoxy, etc., preferably a residue of a benzene or naphthalene ring and Ar<2> is a residue of an optionally substd. arom. ring, preferably a residue of a benzene or naphthalene ring. In the formula II, each of Ar<3> and Ar<4> is a residue of an optionally substd. arom. ring or an optionally substd. aliphatic residue, preferably a residue of a benzene or naphthalene ring, X is -COO- or -OCO- and (n) is an integer of >=2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a charge control agent for developing an electrostatic image used in an electronic copying machine and the like, and a charge for applying a charge to a toner using the same and a toner used for developing an electrostatic image. It is related to the imparting material.

[0002]

2. Description of the Related Art In a developing process, a developer used in an electronic copying machine or the like is once adhered to an image carrier such as a photoreceptor on which an electrostatic image is formed, and then is exposed to light in a transfer process. After being transferred from the body to the transfer paper, it is fixed on the copy paper surface in a fixing step. At that time, as a developer for developing an electrostatic image formed on the latent image holding surface, a two-component developer composed of a carrier and a toner and a one-component developer that does not require a carrier (magnetic toner or Non-magnetic toner) is known.

Incidentally, one of the important characteristics required of the toner is chargeability. That is, an appropriate level of positive or negative charge is generated by contact with a carrier, a developing tank, a developing roller, a layer forming blade, and the like, and the charge level is almost stable over time even during continuous use or under adverse effects. Is required. To impart chargeability to the toner, the binder resin or the colorant itself may be used, but it is difficult to obtain sufficient chargeability. Therefore,
Conventionally imparts chargeability to toner (charge control agent)
It has been known that a toner contains a positively charged nigrosine dye, a quaternary ammonium salt, a negatively charged metal-containing monoazo dye, a salicylic acid metal complex, a copper phthalocyanine pigment, and the like.

[0004]

However, these conventional charge control agents have several problems in terms of the effect of imparting chargeability and other characteristics required for the toner. Part 1
One is the safety of the toner. Most of the conventional charge control agents, particularly negative charge control agents, are for example the metal-containing dye types containing a metal such as chromium, because the applied charge level is high. However, it is preferable not to use a metal, such as chromium, whose safety is questionable, such as chromium, as a component of a substance such as toner, which is used very close to the human body. In recent years, in particular, the importance of such safety has been increasing, and the charge control of the toner, which does not contain a metal such as chromium as much as possible, has a better chargeability than before, and is excellent in other toner required characteristics. The development of agents is desired.

[0005] A second problem of the toner is charging stability. Conventional charge control agents often have a high charge level but do not have sufficient charge stability.For example, the charge level changes over time during continuous copying and continuous printing, causing copy smearing. Have the problem of In particular, these problems tend to increase especially in recent years as copiers and the like that process a large number of sheets continuously and at a high speed are required, and the development of a charge control agent having more excellent charge stability has been required. I have.

On the other hand, not only the charge control agent as described above, but also the improvement of the charge imparting property to the toner is caused by the conveyance, regulation, or friction of a carrier, a developing sleeve, a layer forming blade, etc. which come into contact with the toner during the developing process. A member (hereinafter referred to as a “charge applying material” including a material capable of applying a charge necessary for development to a toner or contacting the toner in advance in a developing process or prior thereto, or an auxiliary charge. Or collectively refer to members). The charge imparting material is required to have high durability against friction with the toner, and it is particularly desirable that the carrier can be used without replacement for a long period of time.

[0007]

Accordingly, the present inventors have provided a high-quality electrostatic image developing toner which is excellent in charge stability and is less likely to generate copy stains even if it is not metal-containing.
In order to provide a charge-imparting material capable of obtaining an image excellent in fine-line reproducibility and gradation without deterioration in performance over a long period of use.
As a result of intensive studies, they have found that these problems can be solved by using a compound having a specific structure as a charge control agent, and have reached the present invention.

[0008] That is, an object of the present invention is to provide a charge control agent which is excellent in charge stability without containing a metal, and which is also excellent in other required characteristics of toner, for example, moisture resistance, light resistance, heat resistance and the like. Another object of the present invention is to provide a charge-imparting material and a high-quality toner in which print density is moderate and stable even under adverse effects during continuous use, and hardly causes copy smear. Another object of the present invention is to provide a charge control agent excellent in safety. That is, the gist of the present invention is a charge control agent for developing an electrostatic charge image, which is a compound represented by the following general formula (I) or (II).

[0009]

Embedded image Ar ¹ —COO—Ar ² (I)

(Wherein, Ar¹Is unsubstituted or substituted
Or an unsubstituted alkyl group, alkoxyl group, amino
Group, alkylamino group, halogen group, nitro group and
Substituted with one or more groups selected from the group consisting of
Represents an aromatic ring residue, ^TwoIs substituted or unsubstituted
Represents an aromatic ring residue. )

[0011]

Embedded image

(Wherein, Ar ³ and Ar ⁴ each represent a substituted or unsubstituted aromatic ring residue or a substituted or unsubstituted aliphatic residue, and X represents —COO— or —O
CO-, and n represents an integer of 2 or more. However,
A plurality of Ar ⁴ and X may be different from each other. ), A resin, a colorant, and a charge controlling agent for developing an electrostatic image, and a toner for developing an electrostatic image, and the charge controlling agent for developing an electrostatic image is provided on at least one surface of the base material. In the charge imparting material for developing an electrostatic image.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Ar ¹ in the above general formula (I)
And the aromatic ring residue of Ar ² may be a carbocyclic ring or a heterocyclic ring, or may be a carbocyclic ring, a heterocyclic ring, or a condensed carbon and heterocyclic ring. Specific examples include aromatic ring residues having 4 to 30 carbon atoms, such as benzene ring residues, naphthalene ring residues, anthracene ring residues, phenanthrene ring residues, furan ring residues,
Thiophene ring residue, pyrrole ring residue, imidazole ring residue, oxazole ring residue, thiazole ring residue, pyridine ring residue, carbazole ring residue, fluorene ring residue, fluorenone ring residue, dibenzofuran ring residue, Examples include a dibenzothiophene ring residue and a benzocarbazole ring residue. Preferably, a benzene ring residue, a naphthalene ring residue,
Furan ring residues are good. Ar ¹ and Ar ² may be the same or different from each other.

Ar ¹ may be unsubstituted but has a substituent selected from a substituted or unsubstituted alkyl group, alkoxyl group, amino group, alkylamino group, halogen group, nitro group and phenyl group. Is also good. Specific examples of the substituent include a methyl group, an ethyl group, an n-propyl group, i
so-propyl group, n-butyl group, iso-butyl group,
And an unsubstituted alkyl group (preferably having 1 to 6 carbon atoms) such as a tert-butyl group, a haloalkyl group (fluoromethyl group, difluoromethyl group, trifluoromethyl group, chloromethyl group, bromomethyl group, fluoroethyl group, A substituted alkyl group such as a hydroxyalkyl group (e.g., a hydroxymethyl group, a dihydroxymethyl group, a trihydroxymethyl group, a hydroxyethyl group, a hydroxypropyl group, and a hydroxybutyl group); Preferably those having 1 to 6 carbon atoms), alkoxyl groups such as methoxyl group, ethoxyl group, n-propoxyl group, iso-propoxyl group, n-butoxyl group, iso-butoxyl group and tert-butoxyl group (preferably Has 1 to 6 carbon atoms), an amino group, an alk Amino group, and alkylamino group such as a dialkylamino group (preferably 1 to carbon atoms
10), a halogen group such as a fluorine atom, a chlorine atom and a bromine atom, a nitro group, a phenyl group and the like. Ar
¹ is preferably substituted with a tert-butyl group, a haloalkyl group, or a halogen group, or is unsubstituted.

Ar ² may be unsubstituted, but may be an optionally substituted alkyl group, an optionally substituted alkoxyl group, an optionally substituted amino group, a halogen group, a nitro group, a hydroxyl group, May have a substituent selected from an optionally substituted phenyl group. Ar ² is
It is preferably substituted with a tert-butyl group, a haloalkyl group, or a halogen group, or unsubstituted. When both Ar ¹ and Ar ² have a substituent, they may have different substituents.

In the above general formula (II), Ar ³ and Ar
⁴ may be an aromatic ring residue or an aliphatic residue, but the aromatic ring residue may be a carbocyclic ring or a heterocyclic ring, and further, carbocyclic rings, heterocyclic rings or a condensed carbon and heterocyclic ring. May be done. Specific examples include aromatic ring residues having 4 to 30 carbon atoms, such as benzene ring residues, naphthalene ring residues, anthracene ring residues, phenanthrene ring residues, furan ring residues, and thiophene ring residues. Group, pyrrole ring residue, imidazole ring residue, oxazole ring residue, thiazole ring residue, pyridine ring residue, carbazole ring residue, fluorene ring residue, fluorenone ring residue, dibenzofuran ring residue, dibenzothiophene ring And a benzocarbazole ring residue. Preferably, a benzene ring residue, a naphthalene ring residue and a furan ring residue are preferred.

Ar ³ and Ar ⁴ may be the same or different from each other. Although the compound represented by the general formula (II) are those having a plurality of Ar ^4, a plurality of Ar ⁴ in the present invention does not necessarily represent the same aromatic ring residue, a plurality of Ar ⁴ Are different from each other and are included in the above general formula (II). Ar ³ or A
Each of r ⁴ may be unsubstituted or may have a substituent. Specific examples of the substituent include a methyl group, an ethyl group, an n-propyl group, an iso-propyl group, an n-butyl group, an iso-butyl group, a tert-butyl group, and a haloalkyl group (fluoromethyl group, difluoromethyl group, Trifluoromethyl group, chloromethyl group, bromomethyl group,
Fluoroethyl group, fluoropropyl group, fluorobutyl group, etc.), hydroxyalkyl group (hydroxymethyl group, dihydroxymethyl group, trihydroxymethyl group,
A substituted or unsubstituted alkyl group (preferably having 1 to 6 carbon atoms) such as a hydroxyethyl group, a hydroxypropyl group, or a hydroxybutyl group; an amino group, an alkylamino group or a dialkylamino group; An amino group (preferably having 0 to 10 carbon atoms),
Methoxyl group, ethoxyl group, n-propoxyl group, i
alkoxyl groups (preferably having 1 to 6 carbon atoms) such as so-propoxyl group, n-butoxyl group, iso-butoxyl group and tert-butoxyl group; hydroxyl groups; halogens such as fluorine atom, chlorine atom and bromine atom Group, nitro group, phenyl group and the like. Preferably unsubstituted,
Alternatively, it may be substituted with a tert-butyl group, a haloalkyl group, a hydroxyl group, or a halogen group. Ar ³ and A
When both r ⁴ have a substituent, Ar ³ and Ar ⁴
May have different substituents, and a plurality of Ar ⁴
May have different substituents from each other. Also, Ar
^{When 3} or Ar ⁴ has a plurality of substituents, those substituents may be the same or different.

As with Ar ⁴ , even if they are different from each other, a plurality of Xs are included in the general formula (II). n is preferably 2 to 4, and more preferably 2. The compound represented by the general formula (I) can be easily synthesized, for example, by the following synthesis method. For example, general formulas (III) and (IV)

[0019]

Ar ^1- (COCl) (III) Ar ² -OH (IV)

The compound represented by the formula (where Ar ¹ and Ar ² have the same meanings as in the above formula (I)) is converted into, for example, a compound of the formula (III): the formula (IV) = 1: 1 (molar ratio) ), And then reacted in a solvent such as toluene in the presence of a base.

Specific examples of preferred compounds represented by the above general formula (I) include the compounds represented by the structural formulas shown in Table 1, but are not limited thereto. Absent. For example, when X = —COO—, the compound represented by the general formula (II) can be easily synthesized by the following synthesis method. For example, general formulas (V) and (VI)

[0022]

Ar ³ — (COCl) _n (V) Ar ⁴ —OH (VI)

(Wherein, Ar ³ and Ar ⁴ represent the above-mentioned general formula (I)
A compound represented by the same meaning as in I), for example, when n is 2, the general formula (V): the general formula (VI) = 1: 2,
When n is 3, general formula (V): general formula (VI) = 1: 3,
When n is 4, general formula (V): general formula (VI) = 1: 4
(All in molar ratio) by reacting them in a reaction system in a solvent such as toluene in the presence of a base.

Specific examples of preferred compounds represented by the above general formula (II) include, but are not limited to, exemplified compounds represented by the structural formulas shown in Tables 2 and 3. Not something.

[0025]

[Table 1]

[0026]

[Table 2]

[0027]

[Table 3]

[0028]

[Table 4]

Next, the case where the charge control agent of the present invention is used for a toner will be described. The toner contains at least a charge control agent, a resin and a colorant. The resin to be contained in the toner can be selected from a wide range including known resins. For example, polystyrene, polychlorostyrene, poly-α-methylstyrene, styrene-chlorostyrene copolymer, styrene-propylene copolymer, styrene-butadiene copolymer, styrene-vinyl chloride copolymer, styrene-vinyl acetate copolymer Styrene-maleic acid copolymer, styrene-acrylate copolymer (styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer, styrene-acrylic acid Octyl copolymer, styrene-phenyl acrylate copolymer, etc.), styrene-methacrylic ester copolymer (styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer) Merged and styrene-phenyl methacrylate Copolymers), styrene -
α-methyl methacrylate copolymer and styrene
Styrene resins such as acrylonitrile-acrylic acid ester copolymers (homopolymers or copolymers containing styrene or styrene substituents), vinyl chloride resins, rosin-modified maleic resins, phenolic resins, epoxy resins, polyester resins (saturated) , Low molecular weight polyethylene, low molecular weight polypropylene, ionomer resin,
Polyurethane resins, silicone resins, ketone resins, ethylene-ethyl acrylate copolymers, xylene resins, polyvinyl butyral resins, etc., are particularly preferred for use in the invention. Styrene-acrylate copolymers, styrene-methacrylic Acid ester copolymer resins, polyester resins, epoxy resins and the like can be mentioned. Further, the above-mentioned resins are not limited to being used alone, and may be used in combination of two or more.

The colorant to be contained in the toner can be selected from a wide range including known ones. For example, carbon black, lamp black, iron black, ultramarine, nigrosine dye, aniline blue, phthalocyanine blue, phthalocyanine green, hansa yellow , Chrome yellow,
Rose bengal, triarylmethane dyes, monoazo and disazo dyes and the like can be mentioned.

The compound represented by the above general formula (I) or (II) is white (or pale yellow), and is contained in, for example, blue, red, yellow and other color toners used for full-color image formation. In this case, a colorant composed of a dye or pigment having a corresponding color tone is used. The content of the colorant is
The amount is preferably 3 to 20 parts by weight based on 100 parts by weight of the resin.

As a method for incorporating the compound represented by the general formula (I) or (II) into the toner, there are an internal addition method in which the toner is added and mixed together with a resin, and an external addition method in which the toner particles are added and mixed after formation. And the like, but the internal addition method is more general and preferable. The content of the compound represented by formula (I) or (II) in the toner is preferably 0.1 to 20 parts by weight, more preferably 0.1 to 15 parts by weight, based on 100 parts by weight of the resin. , More preferably 0.5 to 5
Parts by weight. If the content of the compound represented by the general formula (I) or (II) is too small, the effect of improving the chargeability is not improved, and if the content is excessive, the quality of the toner is deteriorated.

In the toner of the present invention, apart from the compound represented by the above general formula (I) or (II), other charge control agents including known ones, for example, a nigrosine dye,
A secondary ammonium salt, a metal-containing complex compound and the like may be contained. Further, other known additives such as a solid electrolyte, a polymer electrolyte, a charge transfer complex, a conductor such as a metal oxide such as tin oxide, a semiconductor or a ferroelectric, and a magnetic substance are added to the toner of the present invention. The electrical properties of the toner can be controlled. In addition, some toners have thermal characteristics,
It is also possible to add various plasticizers such as low-molecular-weight olefin polymers and auxiliaries such as release agents for the purpose of adjusting physical properties and the like. Further, TiO ₂ , Al ₂ O ₃ ,
By adding fine powder such as SiO ₂ and coating the surface of the toner particles with these, it is possible to improve the fluidity and aggregation resistance of the toner.

The charge control agent of the present invention is particularly preferably used for a negatively chargeable toner. The toner may be produced by kneading the above components in a kneader or the like, cooling, pulverizing and classifying. Further, the toner of the present invention is applicable not only to a two-component developer used with a carrier but also to a so-called one-component developer (magnetic toner or non-magnetic toner) such as encapsulated toner, polymerized toner, and magnetite-containing toner. Can be. The average particle size of the toner is preferably 5 to 20 μm.

Examples of the carrier for forming the developer by mixing with the toner of the present invention include a magnetic substance such as a known iron powder-based, ferrite-based, and magnetite-based carrier, a magnetic substance having a resin coating on the surface thereof, or a magnetic resin. A carrier can be used. As the coating resin of the resin coating carrier, generally known styrene resin, acrylic resin, styrene acrylic copolymer resin, silicone resin, modified silicone resin, fluorine resin, or a mixture of these resins, etc. Available but not limited to these. The average particle size of the carrier is not particularly limited, but preferably has an average particle size of 10 to 200 µm. These carriers are used in an amount of 5 parts per 1 part by weight of toner.
It is preferable to use 100 parts by weight.

Next, the case where the charge control agent of the present invention is used as a charge imparting material will be described. The charge imparting material has the compound represented by the general formula (I) or (II) on at least a part of its surface. The charge controlling agent of the present invention, together with a binder resin, if necessary, is applied or coated by dissolving or dispersing in a solvent or a dispersion medium to a base material of the charge imparting material by dipping, spraying, brushing, or the like. Or, when the base material is in the form of carrier particles, by dipping it in the above coating solution, mixing and drying, or by a method such as coating a direct mixture with the base material with a fluidized bed, etc., onto the base material. If a coating layer containing the charge control agent is formed, the charge imparting material of the present invention can be obtained.
Alternatively, a charge-imparting material may be obtained by directly melting and kneading the binder resin and the charge control agent and extruding and laminating the charge control agent on a base material. Further, the charge control agent may be contained in a moldable resin, and the charge control agent may be formed into a shape of carrier particles, a developing sleeve, or a layer forming blade to serve as a charge imparting material.

[0037]

The present invention will be described in more detail with reference to the following examples. In the following examples, “parts” simply means “parts by weight”. Further, the exemplified compounds correspond to the compounds in Table 1. Example 1

[0038]

Table 5 Polyester resin (FC-023 manufactured by Mitsubishi Rayon Co., Ltd.) 100 parts Carbon black (MA-100 manufactured by Mitsubishi Chemical Corporation) 4 parts Exemplified compound (1) 3 parts

The above materials were mixed and kneaded, and crushed and classified to obtain a black toner having an average particle diameter of 9 μm. 5 parts of this toner and 100 parts of a ferrite carrier having an average particle diameter of about 100 μm were mixed and stirred to prepare a developer. Next, when this developer was actually photographed by a copying machine using selenium as a photoreceptor, a clear copy was obtained.

Example 2 The procedure of Example 1 was repeated except that 3 parts of the exemplary compound (2) was used as the charge controlling agent. As a result, a good copy was obtained as in Example 1. Example 3 The same procedures as in Example 1 were carried out except that 3 parts of the exemplary compound (16) was used as the charge controlling agent, whereby a good copy was obtained as in Example 1.

Example 4 The procedure of Example 1 was repeated except that 3 parts of the exemplified compound (18) was used as a charge controlling agent. As a result, a good copy was obtained as in Example 1. Example -5 The same procedures as in Example 1 were carried out except that 3 parts of Exemplified Compound (25) was used as the charge controlling agent. As in Example 1, a good copy was obtained.

Example -6 The same procedures as in Example 1 were carried out except that 3 parts of Exemplified Compound (33) was used as the charge controlling agent, whereby a good copy was obtained as in Example 1. Example -7 The same procedures as in Example 1 were carried out except that 3 parts of Exemplified Compound (39) was used as the charge controlling agent, whereby a good copy was obtained as in Example 1.

Example -8 The same procedures as in Example 1 were carried out except that 3 parts of Exemplified Compound (40) was used as the charge controlling agent, whereby a good copy was obtained as in Example 1. Example -9 A developer composed of a toner and a ferrite carrier was prepared in the same manner as in Example 1, 10 g of the developer was placed in a 20-ml sample bottle, mixed and stirred using a reciprocating shaker, and the charge amount with respect to the shaking time was blown off. It was measured using the method. Table 4 shows the charge amount.

[0044]

[Table 6] Table 4

[0045]

According to the present invention, the toner for developing an electrostatic image using the charge control for developing an electrostatic image and the charge-imparting material are excellent in safety and stable in charging, and do not generate copy stains due to continuous copying. It is a high quality electrostatic charge image developing toner and charge providing material.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kyoko Endo 1000 Kamoshitacho, Aoba-ku, Yokohama-shi, Kanagawa Prefecture Mitsubishi Chemical Research Institute Yokohama Research Laboratory

Claims (3)

[Claims] 1. A compound represented by the following general formula (I) or (II)
For electrostatic image development characterized by being a compound to be developed
Control agent Ar 1¹-COO-Ar^Two ... (I) (wherein, Ar¹Is unsubstituted, or substituted or unsubstituted
Alkyl group, alkoxyl group, amino group, alkyl group
Consists of mino, halogen, nitro and phenyl groups
Aromatic residue substituted with one or more groups selected from the group
Ar represents a group ^TwoIs a substituted or unsubstituted aromatic ring residue
Represents )(Wherein, Ar^ThreeAnd Ar^FourAre replaced or omitted, respectively.
A substituted aromatic ring residue or a substituted or unsubstituted aliphatic
X represents -COO- or -OCO-
And n represents an integer of 2 or more. However, a plurality of Ar^Four
And X may be different from each other. ). 2. An electrostatic image developing toner comprising a resin, a colorant, and the electrostatic image developing charge control agent according to claim 1. 3. A charge providing material for developing an electrostatic image, comprising the charge control agent for developing an electrostatic image according to claim 1 on at least a part of the surface of the base material.