JPH02293870A - Toner for developing electrostatic charge image - Google Patents

Abstract

PURPOSE:To improve electrostatic chargeability and particularly the rise of electrostatic charge by incorporating a resin, carbon black and specific pigment into the toner. CONSTITUTION:The resin, the carbon black and the pigment expressed by formula I are incorporated as essential components into the toner. In the formula I, X1-4 denotes the compd. expressed by formula II; -H, etc.; R, R' denote 1 to 5C alkylene group. However, the case in which all of X4 to X4 are -H is excluded. All of known binder resins are usable; for example, honopolymers of styrene, such as polystyrene, poly p-chlorstyrene, and the substitution produce thereof, chlorinated paraffin, paraffin wax, etc., are usable alone or in combination. The electrostatic charge characteristics are improved in this way and sharp images are obtd.

Description

[Detailed description of the invention]

[Field of Industrial Use] The present invention relates to a toner for developing electrostatic images in electrophotography, electrostatic recording, electrostatic printing, etc. [Prior Art] Electrostatic printing, electrophotography, and the like are well-known methods for forming visible images by developing electrical latent images with toner. For example, as an electrophotographic method, U.S. Patent No.
Various methods described in Japanese Patent Publication No. 297,691, Japanese Patent Publication No. 42-23910, Japanese Patent Publication No. 43-24748, etc. are well known. In general, an electrical latent image is formed on a photoreceptor exhibiting photoconductivity by various means using a leading conductive material, and then the latent image is developed with toner to obtain a visible image, or If necessary, heat the powder image after transferring it to paper, etc.
A visible image is obtained by fixing under pressure or solvent vapor. Conventionally, carbon black has often been used as a colorant in toners for developing electrostatic images. In addition, various dyes and pigments may be used as charge control agents in such toners. For example, C. I. Pigment blue 15 is a representative example of copper-captate cyanine, a copper-captated cyanine sulfonylamine conductor described in JP-A-52-45931, and C described in JP-A-60-7435. ．． I. Examples include Plga+ent Red 48. However, when sulfonylamine derivatives of copper-hydrocyanine and copper-hydrocyanine are used together with carbon plaque, the toner exhibits a sharp black color with a bluish tinge, but on the other hand, because hydrogen groups and sulfone groups are hygroscopic, ,
In addition, the C.I. I. Pigment
When a red dye or pigment like Red 48 is used together with carbon plaque, the toner becomes reddish and the image lacks sharpness. Furthermore, when this pigment is used, its compatibility with the resin is insufficient, resulting in poor dispersibility of the colorant, reducing the coloring power of carbon black, and causing local charging variations. [Problems to be Solved by the Invention] The purpose of the present invention is to solve the above-mentioned problems, have sufficient coloring power, exhibit sharp images, have excellent compatibility with resins, and have excellent charging properties, especially frictional charging. An object of the present invention is to provide a toner for developing electrostatic images that has a good charge build-up. [Means and effects for solving the problems] The features of the present invention are that a resin, carbon black, and a compound of the general formula (
The toner for developing electrostatic images contains the pigment shown in 1) as an essential component. General formula (I) R, R': Alkylene group having 1 to 5 carbon atoms, however, XI""
'Except when all of X4 are -H<. ] All known binder resins can be used for the toner of the present invention, including monopolymers of styrene and its substituted products such as polystyrene, poly-p-chlorostyrene, polyvinyltoluene, and styrene-p-chlorostyrene. Chlorstyrene copolymer,
Styrene-propylene copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer,
Styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate Copolymer, styrene-butyl methacrylate copolymer, styrene-α-methyl chloromethacrylate copolymer, styrene-acrylic nitrile copolymer, styrene-vinyl methyl ether copolymer, styrene-vinylethyl ether copolymer, styrene -vinylmethylketone copolymer, styrene-butadiene copolymer, styrene-isobrene copolymer, styrene-acrylic nitrile-indene copolymer, styrene-maleic acid copolymer, styrene-maleic acid ester copolymer, etc. Styrenic copolymers, polymethyl methacrylate, polybutyl methacrylate, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, polyester, polyurethane, polyamide, epoxy resin, polyvinyl butyral,
Polyacrylic acid resin, rosin, modified rosin, terpene resin, phenolic resin, aliphatic or alicyclic hydrocarbon resin,
Aromatic petroleum resins, chlorinated paraffin, paraffin wax, etc. can be used alone or in combination. Any carbon black that can be colored can be used as the carbon black used in the present invention, and examples thereof include furnace black, channel black, thermal black, lamp black, and the like. The amount of carbon black added is 2 to 13.5 parts by weight per 100 parts by weight of the resin. If the amount added is less than 2 parts by weight, sufficient coloring power may not be obtained and the color of the resin or pigment may change. I am affected by it. If more than 13.5 parts by weight is added, sufficient triboelectric charging cannot be obtained due to the conductivity of carbon black, and the environmental stability of charging will be impaired. The amount is preferably 3 parts by weight to 10 parts by weight, and more preferably 3 parts by weight to 7 parts by weight. Particularly important constituents of the toner of the present invention are the copper-phthalocyanine compounds represented by the above-mentioned general formula (1). Specific examples of the compound represented by the general formula CI) include
, etc. When used with carbon black, this compound has high compatibility with the binder resin, so it is uniformly dispersed and provides a good sharp image to the toner. Furthermore, since the terminal hydrogen group of the compound is substituted with the terminal group shown in a) to d) above, charging properties are improved, and charging defects due to moisture absorption can be prevented, especially under high humidity conditions. The amount of the compound represented by the general formula (I) to be added to carbon black is in the range of 10 to 50 to 100 parts of carbon black. If it is less than 1O, the charge control role of the compound represented by the general formula (I) will not be sufficient, and if it exceeds 50, the blue tint will be too strong and may shift from black to blue. Preferably it is 20 to 40 to 100 of carbon black. Furthermore, the toner of the present invention is charged as necessary! #J preparation may be added. For example, when used as a negative toner, a metal chelate of alkyl salicylic acid can be used, and when used as a positive toner, a dimethylaminoethyl methacrylate-styrene copolymer can be used. Furthermore, for the developer in which the toner of the present invention is used, a fluidity modifier such as colloidal silica is added to the toner at a rate of 0.
01% to 5% by weight (preferably 0.1% to 2l)
It may be added in an amount of about i amount%). Furthermore, when using a carrier in the developer, conventionally known carriers can be used. For example, surface oxidized or unoxidized iron, nickel, copper, zinc,
Metals such as cobalt, manganese, chromium, and rare earths, their alloys or oxides, and ferrites made of the above metals can be used, and there are no special restrictions on the manufacturing method. Further, a system in which the surface of the carrier is coated with a resin or the like is particularly preferable as the developer of the present invention. As a method for this, any conventionally known method can be applied, such as a method in which a coating material such as a resin is dissolved or suspended in a solvent, applied, and adhered to a carrier, or a method in which a powder is simply mixed. Next, a general method for manufacturing the toner of the present invention will be explained. First, the resin, carbon black, and general formula (I) (and optionally a charge control agent) are uniformly dispersed using a Henschel mixer or the like, and then melt-kneaded using a 21-der extruder roll mill or the like. Next, the kneaded material is coarsely ground using a cutter mill, hammer mill, etc., and then finely ground using a jet mill, type mill, etc. The finely pulverized product is classified using a DS or zigzag classifier, and if necessary, silica or the like is dispersed in the classified product using a Henschel mixer or the like. [Example] The present invention will be explained in detail with reference to Examples below. In addition, all parts in the examples indicate parts by weight. A sharp black image without blur was obtained. Compound [11] in Example 1 x 1 to x 3...
- The above compound is uniformly dispersed using a Henschel mixer, then melt-kneaded using a roll mill, cooled, and then coarsely ground using a hammer mill, and then finely ground using an air jet type pulverizer. The obtained fine powder was classified and 1 to 20
Select μ and use it as toner. A developer was prepared by mixing 90 parts of carrier (Cu-Zn ferrite) with 10 parts of this toner. Using this developer, copies were made using an NP-5000 copying machine (manufactured by Canon ■) having a magnetic brush developing device in environments ranging from high temperature to low temperature and low humidity. As a result of measuring the amount of charge in the two-component blow-off method of the developer, the environmental dependence was good (Fig. 1), and when the copy was subjected to the same procedure as in Example 1, the charging property was also good (Fig. 1). ), and a sharp black image was obtained. A toner was produced using the above compound in the same manner as in Example 1, and 1% by weight of colloidal silica was added to the toner.
Copying was performed using a CLC-1 copying machine (manufactured by Canon ■). The copy exhibited an extremely sharp black color with no fog. In addition, durability tests were conducted using a CLC-1 copying machine modified to detect inductance toner concentration. Result 2
Even after 10,000 prints, clear black images with no fogging or smearing were obtained. In Moxibustion Example 1, the compound [11 was replaced by C. I. P
A toner and developer were prepared in the same manner as in Example 1, except that igment blue 15 was used in 2 parts. Charging was insufficient in a high-temperature environment (Figure 1), causing fog and toner scattering on the image. Comparative Example 2 In Example 1, C.I. I. P
A toner and developer were prepared in the same manner as in Example 1, except that igment Red 48 was used in 2 parts. NP-5
Images copied using a 000 copying machine (manufactured by Canon ■) had a reddish tinge, which was particularly noticeable in the halftone areas, lacked sharpness, and uneven shading occurred due to localized electrostatic charge variations. A toner and a developer were prepared in the same manner as in Example 1 except that the amount of carbon black was increased to 20 parts by weight and Compound [11 was not used. The amount of charge on the toner was low (Figure 1), causing a large amount of fog on the image. [Effects of the Invention] The present invention utilizes a compound for the purpose of adjusting the color tone and the amount of charge of black toner.

This relates to a toner for developing electrostatic images containing compound [1], which is characterized by the addition of compound [1] to improve charging characteristics and to obtain sharp images.

[Brief explanation of drawings]

Claims (1)

[Claims] (1) Resin, carbon black and the following general formula (I)
A toner for developing an electrostatic image, comprising a pigment represented by: General formula (I) ▲There are mathematical formulas, chemical formulas, tables, etc.▼ [X_1＿～＿4: ▲There are mathematical formulas, chemical formulas, tables, etc.▼
, ▲There are mathematical formulas, chemical formulas, tables, etc. ▼, -H, R, R'
: Alkylene group having 1 to 5 carbon atoms, except when all of X_1 to X_4 are -H. ]
(2) The toner for developing electrostatic images according to claim 1, wherein the total amount of the colorant of the carbon black and the pigment represented by the general formula (I) is 15 parts by weight or less based on 100 parts by weight of the resin. (3) The toner for developing electrostatic images according to claim (1) or (2), wherein the ratio of the added amount of the carbon black to the pigment represented by the general formula (I) is from 100/10 to 100/50.