JPH0844114A - Electrostatic charge controlling agent for development of electrostatic charge image, toner using same and electric charge imparting agent - Google Patents

Abstract

PURPOSE:To obtain an electrostatic charge controlling agent excellent in electrostatic charge stability in spite of a metal-free state and excellent also in other characteristics required by a toner, e.g. moisture, light and heat resistances by using a specified compd. CONSTITUTION:A compd. represented by the formula is used as the objective electrostatic charge controlling agent. In the formula, X is a divalent org. group such as -CH2-, -S- or -SO2-, each of A and B is a residue of an arom. ring which may have a substituent on the ring, a heterocyclic ring or a condensed arom.-heterocyclic ring, the arom. ring is, e.g. a benzene or naphthalene ring and each of R<1> and R<2> is H or acyl such as formyl or acetyl. When this electrostatic charge controlling agent is used, the objective high quality toner for developing an electrostatic charge image excellent in safety, having electrostatic charge stability and not causing the stain of a copy by continuous copying and the objective electric charge imparting agent are obtd.

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 charge image in an electronic copying machine, a toner using the charge control agent, and a charge imparting agent for imparting an electric charge to a toner used for developing an electrostatic charge image. It is about.

[0002]

2. Description of the Related Art A developer used in an electronic copying machine or the like is temporarily adhered to an image bearing member such as a photoconductor on which an electrostatic charge image is formed in the developing process and then exposed in a transfer process. After being transferred from the body to the transfer paper, it is fixed on the copy paper surface in the fixing step. At that time, as a developer for developing the 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 (magnetic toner) not requiring the carrier
It has been known.

By the way, one of the important characteristics required for toner is chargeability. That is, the contact with the carrier or the container wall of the developing tank causes an appropriate level of positive or negative electrification, and the electrification level is substantially stable over time even during continuous use or under adverse influence. Is especially required. The toner may be charged with a binder resin or a colorant itself, but it is difficult to obtain sufficient chargeability.

Therefore, as a charge imparting agent (charge controlling agent) which has been conventionally given to a toner, a positively chargeable nigrosine dye, a quaternary ammonium salt, a negatively chargeable metal-containing monoazo dye, a salicylic acid metal complex, and copper. It has been known that a toner contains a phthalocyanine pigment or the like. by the way,
These conventional charge control agents have some problems in terms of chargeability imparting effect and other required properties of toner.

One of them is the safety of the toner. Conventional charge control agents, especially negative charge control agents, include, for example:
The metal-containing dye type containing a metal such as chromium occupies most of them because of the high charge level imparted. However, it is preferable not to use a metal such as chrome, which has a doubt about safety, as a component of the toner, which is a substance used in a place extremely close to the human body. In particular, in recent years, there has been an increasing demand for such safety, and the toner does not contain metal such as chromium as much as possible, and the chargeability is better than before, and the charge control is excellent in other required toner characteristics. The development of agents is desired.

Further, the second problem of the toner is the safety of charging. Many conventional charge control agents have a high charge level but insufficient charge stability. For example, during continuous copying and continuous printing, the charge level changes over time, causing copy stains. Have the problem of doing. These problems tend to increase in recent years particularly with the demand for a copying machine or the like that can process a large number of sheets continuously and at high speed, and development of a charge control agent having more excellent charge stability is required. There is.

On the other hand, in addition to the above-mentioned charge control agent, the improvement of the charge imparting property to the toner is carried out by the carrier, the developing sleeve, the layer forming blade, etc. which come into contact with the toner during the developing process, the regulation, or the friction. A member (hereinafter referred to as a “charge-giving agent” including these) is a material that contacts the toner prior to or during the development step to give the toner the charge necessary for the development or to supplement the charge. Or the member shall be comprehensively evaluated). The charge-imparting agent is required to have resistance to friction with the toner and to be highly durable, and it is particularly preferable that the carrier can be used without being exchanged for a long period of time.

[0008]

Therefore, the present inventors have provided a high-quality electrostatic image developing toner which is excellent in charging stability and does not easily cause copy stains even if it does not contain metal.
In addition, as a result of earnest studies to provide a charge-imparting agent that provides an image with excellent fine line reproducibility and gradation without deterioration in performance over a long period of time, a compound having a specific structure was identified as a charge control agent. The inventors have found that these problems can be solved by using the above-mentioned method and have reached the present invention.

That is, an object of the present invention is to provide a charge control agent which is excellent in charge stability and does not contain any metal, and which is also excellent in other required properties of toner such as humidity resistance, light resistance and heat resistance. Furthermore, it is to provide a charge-imparting agent and a high-quality toner in which the print density is appropriate and stable even when adversely affected during continuous use, and copy stains are less likely to occur. Another object of the present invention is to provide a charge control agent having excellent safety. That is, the gist of the present invention resides in the general formula (I)

[0010]

Embedded image

(In the formula, X represents a divalent organic group, A and B each represent an aromatic ring residue which may have a substituent, and R ¹ and R ² are each a hydrogen atom or an acyl group. A charge control agent for developing an electrostatic charge image, which is a compound represented by the formula (1), and a toner and a charge imparting agent using the same. Hereinafter, the present invention will be described in detail.

The charge control agent for developing an electrostatic image of the present invention is characterized by being a compound represented by the above general formula (I). In the general formula (I), X is —CH ₂ —, —S—,
It represents a divalent organic group such as —SO ₂ —, —O—, or —NH—. A and B each represent an aromatic ring residue, which may have a substituent on the ring or a heterocycle. Alternatively, these aromatic rings may be further condensed with a heterocycle. R ¹ and R ² each represent a hydrogen atom; an acyl group such as a formyl group, an acetyl group, a benzoyl group and a cinnamoyl group, and a hydrogen atom or an acetyl group is preferable. Specific examples of A and B include benzene ring, naphthalene ring, anthracene ring, phenanthrene ring, carbazole ring, fluorene ring, fluorenone ring,
Examples thereof include a dibenzofuran ring, a dibenzothiophene ring and a benzocarbazole ring. In addition, specific examples of the substituent that may be present on the aromatic ring include a methyl group, an ethyl group, an n-propyl group, an iso-propyl group, an n-butyl group, an iso-butyl group, and a tert-group. An alkyl group such as a butyl group; an amino group, a substituted amino group; an alkoxyl group such as a methoxyl group and an ethoxyl group; a hydroxyl group; a halogen atom such as a chlorine atom and a bromine atom; a nitro group; a phenyl group and the like, and the number of substitutions is 1 And the substituents may be the same or different. Incidentally, A and B in the general formula (I) may be the same or different.

Of the compounds represented by the above general formula (I), those in which R ¹ and R ² are H can usually be easily synthesized by the following synthetic method. For example, the following general formulas (II) and (III)

[0014]

[Chemical 3]

(Where X, A and B are the above general formula (I)
The same meaning as in 1) is obtained by adding dimethylformamide, thionyl chloride and the like to a solvent such as toluene and boiling them to react. Also R
The compound of ¹ (or R ² ) = CH ₃ CO is R ¹ (or R
² ) = H can be obtained by boiling a compound with acetic anhydride. Specific examples of preferable compounds represented by the general formula (I) include, but are not limited to, the exemplified compounds represented by the following structural formulas.

[Exemplified Compound] A and B are represented by -X.
-, - NHCO- and ^{-OR (= - OR 1 = -OR} 2)
Is shown in accordance with IUPAC rules as a single compound that does not bond, and the bonding position of -X-, -CONH, CONH-, is represented by a numeral.

[0017]

[Table 1]

[0018]

[Table 2]

[0019]

[Table 3]

[0020]

[Table 4]

[0021]

[Table 5]

[0022]

[Table 6]

[0023]

[Table 7]

Next, the case where the charge control agent of the present invention is used in 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 such as polystyrene, polychlorostyrene, and poly-styrene.
α-methylstyrene, styrene-chlorostyrene copolymer, styrene-propylene copolymer, styrene-butadiene copolymer, styrene-vinyl chloride copolymer, styrene-vinyl acetate copolymer, styrene-maleic acid copolymer , Styrene-acrylic acid ester copolymer (styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer,
Styrene-octyl acrylate copolymer and styrene-
Phenyl acrylate copolymer, etc.), styrene-methacrylic acid ester copolymer (styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer and styrene-phenyl methacrylate) Copolymers, etc.), styrene-α-chloromethyl acrylate copolymers and styrene-acrylonitrile-acrylic acid ester copolymers and other styrenic resins (styrene or styrene-substituted homopolymers or copolymers), Vinyl chloride resin, rosin-modified maleic acid resin, phenol resin, epoxy resin, polyester resin, low molecular weight polyethylene, low molecular weight polypropylene,
Ionomer resins, polyurethane resins, silicone resins, ketone resins, ethylene-ethyl acrylate copolymers, xylene resins and polyvinyl butyral resins, etc., but as a particularly preferred resin for use in the present invention, styrene-acrylic acid ester copolymers, Examples thereof include styrene-methacrylic acid ester copolymer resin, saturated or unsaturated polyester resin and epoxy resin.

The above resins are not limited to being used alone, but may be used in combination of two or more kinds. 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 blue, nigrosine dye, aniline blue, phthalocyanine blue, phthalocyanine green, Hansa yellow, chrome yellow. , Rose Bengal, triarylmethane dyes, monoazo dyes, diazo dyes and pigments.

The compound represented by the above-mentioned general formula (I) is light yellow and may be contained in color toners such as blue, red and yellow. In this case, coloring composed of dyes and pigments having a corresponding color tone. Use agents. The content of the colorant is preferably 3 to 20 parts by weight with respect to 100 parts by weight of the resin.

As a method for containing the compound represented by the above general formula (I) in the toner, an internal addition method of adding and mixing with a resin in the toner, an external addition method of adding and mixing the toner particles after they are formed, and the like are possible. However, the internal addition method is more general and preferable. The content of the compound represented by the general formula (I) in the toner is 0.1 to 2 with respect to 100 parts by weight of the resin.
The amount is preferably 0 part by weight, more preferably 0.1 to 15 parts by weight, still more preferably 0.5 to 5 parts by weight. If the content of the compound represented by the general formula (I) is too small, the effect of improving the charging property is not improved, and if it is too large, the quality of the toner is deteriorated, which is not preferable.

In the toner of the present invention, in addition to the compound represented by the general formula (I), other charge control agents including known ones, that is, for example, nigrosine dye, quaternary ammonium salt, You may make it contain a metal-containing complex compound etc. Further, the toner of the present invention includes other known additives,
For example, a solid electrolyte, a polymer electrolyte, a charge transfer complex, a conductor such as a metal oxide such as tin oxide, a semiconductor, a ferroelectric substance, a magnetic substance or the like can be added to control the electrical properties of the toner.

In addition to the above, various plasticizers such as low molecular weight olefin polymers and auxiliary agents such as releasing agents may be added to the toner for the purpose of adjusting thermal characteristics, physical characteristics and the like.
Further, by adding fine powder of TiO ₂ , Al ₂ O ₃ , SiO ₂ or the like to the toner particles and coating the surface of the toner particles with these, the fluidity and aggregation resistance of the toner can be improved.

The toner may be produced by kneading the above components with a kneader, cooling, pulverizing and classifying.
In addition to the two-component developer, the toner of the present invention can be applied to so-called one-component developer (magnetic toner) such as encapsulated toner, polymerized toner and magnetite-containing toner. The average particle size of the toner is preferably 5 to 20 μm.

As a carrier which is mixed with the toner of the present invention to form a developer, there are known magnetic substances such as iron powder type, ferrite type and magnetite type carriers, or those whose surface is coated with a resin or magnetic resin. A carrier can be used. As the coating resin for the resin coating carrier, generally known styrene resins, acrylic resins, styrene-acrylic copolymer resins, silicone resins, modified silicone resins, fluorine resins, etc. can be used, but are not limited to these. Not something that is done. The average particle size of the carrier is not particularly limited, but one having an average particle size of 10 to 200 μm is preferable. It is preferable to use 5 to 100 parts by weight of these carriers with respect to 1 part by weight of the toner.

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

[0033]

EXAMPLES The present invention will be described in more detail with reference to examples below, but the present invention is not limited to the following examples as long as the gist thereof is not exceeded. In the following examples, "parts" simply means "parts by weight". Example-1

[0034]

[Table 8] Styrene-based resin (SBM-600 manufactured by Sanyo Kasei) 100 parts Carbon black (MA-100 manufactured by Mitsubishi Kasei) 7 parts Exemplified compound (3) 0.9 parts

The above materials were blended, kneaded, pulverized and classified to obtain a black toner having an average particle size of 11 μm. 5 parts of this toner and 100 parts of an acrylic resin coating carrier having an average particle diameter of about 100 μm were mixed and stirred to prepare a developer. Next, when this developer was actually copied by a copying machine using selenium as a photoreceptor, a clear copy was obtained.

Example-2 Except that 0.9 part of Exemplified Compound (4) was used as the charge control agent, the same procedure as in Example-1 was carried out.
Good copies were obtained as well. Example-3 Except that 0.9 part of Exemplified Compound (6) was used as the charge control agent, the same procedure as in Example-1 was carried out.
Good copies were obtained as well.

Example-4 Example-1 was carried out in the same manner as in Example-1 except that 0.9 part of the exemplified compound (9) was used as the charge control agent.
Good copies were obtained as well. Example-5 Except that 0.9 part of Exemplified Compound (14) was used as a charge control agent, the procedure of Example-1 was repeated.
A good copy was obtained as in No. 1.

Example-6 The procedure of Example-1 was repeated except that 0.9 part of the exemplified compound (16) was used as the charge control agent.
A good copy was obtained as in No. 1. Example-7 The procedure of Example-1 was repeated except that 1.5 parts of the exemplified compound (19) was used as a charge control agent.
A good copy was obtained as in No. 1.

Example-8 The procedure of Example-1 was repeated except that 0.9 part of the exemplified compound (23) was used as the charge control agent.
A good copy was obtained as in No. 1. Example-9 The procedure of Example-1 was repeated except that 1.2 parts of the exemplified compound (24) was used as a charge control agent.
A good copy was obtained as in No. 1.

Example 10 Except for using 2 parts of Exemplified Compound (28) as the charge control agent, the same procedure as in Example 1 was carried out. As a result, good copies were obtained in the same manner as in Example 1. Example-11 The same procedure as in Example-1 was carried out except that 2 parts of the exemplified compound (31) was used as a charge control agent, and good copies were obtained in the same manner as in Example-1.

Example-12 Except for using 2 parts of Exemplified Compound (33) as the charge control agent, the same procedure as in Example-1 was carried out. As a result, good copies were obtained in the same manner as in Example-1. Example-13 The same procedure as in Example-1 was carried out except that 2 parts of the exemplified compound (35) was used as a charge control agent, and good copies were obtained in the same manner as in Example-1.

Example-14 The procedure of Example-1 was repeated except that 0.9 part of Exemplified Compound (39) was used as the charge control agent.
A good copy was obtained as in No. 1. Example-15 The same procedure as in Example-1 was carried out except that 1.2 parts of the exemplified compound (74) was used as a charge control agent.
A good copy was obtained as in No. 1.

Example-16 The same procedure as in Example-1 was carried out except that 2 parts of the exemplified compound (78) was used as a charge control agent, and good copies were obtained in the same manner as in Example-1.

[0044]

EFFECT OF THE INVENTION The toner for electrostatic charge image development using the charge control for developing an electrostatic charge image and the charge-imparting agent according to the present invention have excellent safety and charge stability, and do not cause smearing of copies due to continuous copying. A high-quality electrostatic image developing toner and a charge-giving agent.

Front page continuation (72) Inventor Masako Takeuchi 1000 Kamoshida-cho, Midori-ku, Yokohama-shi, Kanagawa Sanryo Kasei Co., Ltd.

Claims (6)

[Claims] 1. A compound of the general formula (I) (In the formula, X represents a divalent organic group, A and B each represent an aromatic ring residue which may have a substituent, and R represents
¹ and R ² each represent a hydrogen atom or an acyl group)
A charge control agent for developing an electrostatic image, which is a compound represented by: 2. X is --CH _2- , --S--, --SO _2- ,
The charge control agent for developing an electrostatic charge image according to claim 1, which is -O- or -NH-. 3. The charge control agent for electrostatic image development according to claim 1, wherein R ¹ and R ² are each a hydrogen atom or an acetyl group. 4. A benzene ring, naphthalene ring, anthracene ring, wherein A and B each may have a substituent,
The charge control agent for developing an electrostatic charge image according to claim 1, which is a phenanthrene ring, a carbazole ring, a fluorene ring, a fluorenone ring, a dibenzofuran ring, a dibenzothiophene ring or a benzocarbazole ring. 5. A toner for developing an electrostatic charge image, which comprises a resin, a colorant, and the charge control agent for developing an electrostatic charge image according to claim 1. 6. A charge imparting agent for developing an electrostatic charge image, which comprises the charge control agent for developing an electrostatic charge image according to claim 1 on at least a part of the surface thereof.