JPS63281171A - Electrostatic charge image developing toner - Google Patents

Abstract

PURPOSE:To obtain a stable image, irrespective of environmental conditions, by incorporating a specified compound in a resin component in an amount of 0.01-10wt.% of the resin. CONSTITUTION:The resin component contains, in an amount of 0.01-10wt.%, one of the compounds represented by formula I in which R1 is 1-18C alkyl, alkenyl, or aralkyl or aryl optionally substituted on the aromatic ring; each of R2 and R3 is H, halogen, nitro, or the like; each of X and Y is -O-, -COO-, -S-, or the like; M is Sc, Ti, V, or the like; A is H, Na, K,or the like; and each of l, m, and n is 1 or 2, thus permitting a stable high-quality image to be obtained always under whatever environmental conditions.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a toner for developing electrostatic latent images in electrophotography, electrostatic recording, and the like.

[Prior Art] In toner for developing electrostatic images, it is not possible to obtain a certain level of charging performance with the binder resin used alone, so dyes, pigments, etc. are used to control the toner to have the desired triboelectric charging performance. Addition of a charge control substance has been carried out.

Today, the ones that have been put into practical use in the relevant technical field are:
Nigrosine-based dyes are used to impart or control positive charge to the toner, and Japanese Patent Publication No. 45-26478 and Japanese Patent Publication No. 55-427 are used to impart or control negative charge to the toner.
Examples include metal-containing compounds shown in Publication No. 52 and the like. In terms of the ability to impart charge to toner particles, these compounds have particularly excellent properties among charge control substances that have been proposed to date, and they also produce images that are sufficient for practical use in conventional copying machines. We were able to provide a toner that gives you the best results.

[Problems to be solved by the invention] However, as electrophotography and electrostatic recording media become more personalized, faster, and more multifunctional, it is important to understand that electrophotography and electrostatic recording media are becoming more personalized, faster, and more multifunctional. There is a need for a toner that provides images with higher density, no fog, high resolution, clear contrast, or excellent gradation reproducibility. Various development methods have been used, including not only normal development and analog development, but also reversal development, digital development, and low-potential development, and it is required to provide toner that provides high image quality for any development method. ing.

With miniaturization and personalization, products have been used in harsh environments such as high temperature and high humidity in tropical regions, low temperature and low humidity in inland regions, and in places without air conditioning, making them stable under any environment. Furthermore, by increasing the speed, it must be able to withstand use in large quantities at one time or continuous use over long periods of time, and provide stable, high-quality images.

On the other hand, the performance required of toner is not limited to developability.
Various raw materials have been used to improve fixing properties, anti-offset properties, cleaning properties, and anti-blocking properties. As a result, the amount of triboelectric charge of other materials changes significantly, and the ability of charge control agents to simply "impart" or increase the charge is insufficient, and it is not possible to "control" the amount of charge on the toner at a constant level. It should not interfere with the other performance requirements and listed above, but rather should support it.

Toner is required to be controlled so that it is triboelectrically charged to a constant amount even during long-term use under any environment, and as a result, to provide stable high image quality. Therefore, conventional toners are no longer able to satisfy the various requirements mentioned above, and there is a need for improvement in charge control agents.

An object of the present invention is to provide a toner that provides a stable image without being affected by the environment such as temperature and humidity.

Another object of the present invention is to provide a toner that is highly durable and always provides stable images even when used continuously for a long period of time.

Still another object is to provide a toner that provides images with high resolution and fine line reproducibility.

Yet another object is to provide a toner that consistently provides high density, fog-free images.

Still another object is to provide an image that accurately represents delicate images and clearly represents images such as graphics.

Still another object is to provide a toner that can be used in both low-speed and high-speed machines.

Still another object is to provide a toner whose performance does not deteriorate even when left for a long period of time.

[Means and effects for solving the problems] The present invention has the following features:
The toner for developing electrostatic images is characterized in that it contains 0.01 to 10 parts by weight of a compound represented by the following general formula (I) based on 100 parts by weight of the resin component.

(Left below)
R2 and R3 are hydrogen, halogen, nitro, carbon number 1-18
alkyl, alkenyl, aralkyl, aryl,
or represents alkoxy, and X and Y are -o-, -co
o-, -5-1 or -NR5- (R5 is hydrogen or alkyl having 1 to 4 carbon atoms), X represents scandium, titanium, vanadium, manganese, nickel or zinc, A is hydrogen, sodium, Represents potassium, ammonium or organic ammonium, β, l, !
l represents 1 or 2; when it has multiple substituents, they may be the same or different,] As a result of extensive research into toners that can be charged to give stable images over a long period of time, it has been discovered that toners containing a compound represented by general formula (I) are particularly excellent.

That is, the compound represented by the general formula (I) used in the present invention is thermally and temporally stable, has low hygroscopicity,
When included in a toner, it provides a toner with excellent electrophotographic properties even under low humidity conditions. The present invention was achieved by discovering that it is a high quality charge control agent.

In addition, the compound represented by the general formula (I) has the property of having a certain amount of charge due to triboelectrification and stably maintaining a certain amount of charge under any environment. . Moreover, some of the compounds of general formula (I) have low coloring power when kneaded with a resin, and can also be used for color toners.

Further, the toner containing the compound represented by the general formula (I) used in the present invention has good dispersion in the resin, and can be used between toner particles or between the toner and the carrier, and between the toner and the sleeve in the case of -component development. It has been found that the amount of triboelectric charge between the toner and the toner carrier is stable, the distribution of the amount of triboelectricity is sharp and uniform, and the toner can be controlled to the amount of charge suitable for the developing system used.

In particular, it was found that the reduction in image density and fog caused by the charge-up phenomenon in a low-humidity environment were significantly improved. This is because, when toner particles tend to have an excessive charge, the compound of general formula (I) in the toner particles skillfully adjusts the charge of the entire toner particle and maintains the amount of charge at an appropriate constant value. I'm thinking of becoming deaf.

Methods for incorporating the compound represented by general formula (I) used in the present invention into the toner include a method of adding it inside the toner and a method of adding it externally. The amount of these compounds used is determined by the type of binder resin, the presence or absence of additives used as necessary, and the toner manufacturing method, including the dispersion method, and is not uniquely limited. However, it is preferably used in an amount of 0.1 to 10 parts by weight, more preferably 0.1 to 5 parts by weight, based on 100 parts by weight of the binder resin. In addition, when externally added, 0.
01 to 10 parts by weight are preferred.

The compound represented by general formula (I) used in the present invention is
It is obtained by treating a metallizable azo compound with a metallizing agent by a known method, and the counter ion can be changed depending on the subsequent treatment conditions.

For example, 4-acetyl-2-aminophenol is diazotized, β-naphthol is coupled, treated with an inorganic manganese salt, filtered at pH 3 or below, and the precipitate is collected at pH 6 to
By washing until it reaches 7, compound (1) is obtained.

Compound (+) Other specific examples of the compound represented by the general formula (I) used in the present invention include the following:
Synthesized in a similar manner.

Compound (2) Compound (3) (Hereinafter, blank) Compound (4) The compounds used in the present invention can also be used in combination with conventionally known charge control agents.

Any suitable pigment or dye can be used as the colorant used in the present invention, and for example, known dyes and pigments such as carbon black, iron black, phthalocyanine blue, ultramarine blue, quinacridone, and benzidine yellow are used.

The binder resin used in the present invention includes styrene, 0-
Methylstyrene, entero-methylstyrene, p-methylstyrene, p-methoxystyrene, p-phenylstyrene,
p-Chlorstyrene, 3,4-dichlorostyrene, p~
Ethylstyrene, 2,4-dimethylstyrene, p-n-
Butylstyrene, p-tart-butylstyrene, p
- Styrene and its derivatives such as n-hexylstyrene, p-n-octylstyrene, p-n-nonylstyrene, p-n-decylstyrene, p-n-dodecylstyrene; ethylene, propylene, butylene, isobutylene, etc. Ethylenically unsaturated upper olefins; unperturbed polyolefins such as butadiene; vinyl halides such as vinyl chloride, vinylidene chloride, vinyl bromide, vinyl fluoride; vinyl such as vinyl acetate, vinyl propionate, vinyl benzoate, etc. Esters: Methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, methacrylic acid α-methylene aliphatic monocarboxylic acid esters such as phenyl, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate; methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, propyl acrylate, acrylic acid −
n-octyl, dodecyl acrylate, 2-acrylate
Ethylhexyl, stearyl acrylate, acrylic acid-
Acrylic acid esters such as 2-chloroethyl and phenyl acrylate; Vinyl ethers such as vinyl methyl ether, vinyl ethyl ether, and vinyl isobutyl ether; Vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone, and methyl isopropenyl ketone; Tovinylvirol, N -N-vinyl compounds such as vinyl carbazolendole and N-vinylpyrrolidone; vinylnaphthalenes; acrylic acid or methacrylic acid derivatives such as acrylonitrile, methacrylonitrile, and acrylamide; carboxyl compounds such as acrylic acid, methacrylic acid, maleic acid, and fumaric acid Vinyl compound derivatives having groups; Hafestel such as maleic acid Hafestel and fumaric acid Hafestel; maleic anhydride, maleic ester, fumaric acid ester derivatives; homopolymers, copolymers, polyesters, polyurethanes, etc. , epoxy resin, polyvinyl butyral, rosin, modified rosin, terpene resin, phenol resin, aliphatic or alicyclic hydrocarbon resin, aromatic petroleum resin, helobarafine, paraffin wax, etc. can be used alone or in combination.

In particular, binder resins for toners used in pressure fixing systems include low molecular weight polyethylene, low molecular weight polypropylene, ethylene-vinyl acetate copolymers, ethylene-acrylic acid ester copolymers, higher fatty acids, polyamide resins, polyester resins, etc. can be used alone or in combination.

Further, when the toner of the present invention is used as a two-component developer, it is mixed with carrier powder.

All known carriers can be used in the present invention, such as magnetic powders such as iron powder, ferrite powder, and nickel powder, glass beads, etc., and carriers whose surfaces have been treated with resin, etc. Things can be given.

Furthermore, the toner of the present invention is capable of developing while applying an alternating electric field between the developer carrier and the latent image carrier in the development region of the developer carrier facing the latent image carrier for holding the latent image. In an image forming method in which an image is developed with a non-magnetic toner, magnetic particles having a true specific gravity of 6 or less and coated with an electrically insulating resin increase the amount of magnetic particles present in the development area of a developer carrier. 5 to 1001 g/c 2, and the magnetic brush is formed to have a non-contamination between the latent image carrier and the surface of the developer carrier and the surface of the magnetic brush formed on the surface of the developer carrier in the development area. It is also used in an image forming method characterized by developing a latent image while reciprocating magnetic toner.

Furthermore, the toner of the present invention can further contain a magnetic material and be used as a magnetic toner. The magnetic materials contained in the magnetic toner of the present invention include iron oxides such as magnetite, magnetite, and ferrite, and iron oxides containing other metal oxides;
Fe, Go, old metals, or these metals and AI! , Co, Cu.

Pb, Mg, Old, Sn, Zn, Sb, Be
, Bi, Cd, Ca, Mn.

Examples include alloys with metals such as Se, Ti, W, and V, and mixtures thereof. These ferromagnetic materials have an average grain size of about 0.1 to 2 layers, and their magnetic properties when applying IOK 6e are coercive force of 20 to 150 lee, and saturation magnetization of 50 to 20 lee.
0emu/g (preferably 50-100e fat u/g)
, a residual magnetization of 2 to 20 u/H is desirable, and the amount contained in the toner is 20 to 200 parts by weight, particularly preferably 40 to 150 parts by weight, per 100 parts by weight of the resin component.
Parts by weight.

The toner of the present invention may be mixed with additives as required. Examples of additives include lubricants such as Teflon, polyvinylidene fluoride, and fatty acid metal salts; or cerium oxide,
Abrasive agents such as titanate, rontium, and silicon carbide; or fluidity imparting agents such as colloidal silica and alumina;
There are anti-caking agents; conductivity imparting agents such as carbon black and tin oxide; and fixing aids such as low molecular weight polyethylene. , microcrystalline wax, carnauba wax, Sasol wax, etc. in a waxy substance of 0.5 to 5
It is also possible to add about wt%.

In manufacturing the toner according to the present invention, the constituent materials are sufficiently mixed using a ball mill or other mixer, and then
Thoroughly knead using a heat kneader such as a hot roll, niegu, extruder, etc., cool and solidify, then obtain by mechanical crushing and classification. After dispersing the constituent materials in a binder resin solution, spray drying. A polymerization toner production method in which the monomers to constitute the binder resin are mixed with predetermined materials to form an emulsified suspension and then polymerized; In the microcapsule toner, a method of containing a predetermined material in the core material, the shell material, or both can be applied.

In the toner of the present invention, the acid value of the soluble component of the toner is preferably 50 or less, more preferably 25 or less, and when the acid value of the soluble component of the toner is below the above range, The charge control action of the compound of general formula (I) used in the present invention works most effectively, exhibits superior developability, and can provide high-quality images. Acid value is 50
If it exceeds 100%, the amount of charge becomes excessive under low humidity, resulting in a decrease in developability.

In the present invention, the acid value value is Sample 1. It is a numerical value expressed in 1 g of potassium hydroxide required to neutralize the hydroxide, and is measured as follows.

2 g of the soluble component was dissolved in 200 g of a mixed solvent of toluene/ethanol = 2/l, and phenolphthalein was used as an indicator. Titrate with IN potassium hydroxide solution.

Further, in the heat fixing toner of the present invention, 1. The molecular weight of the tetrahydrofuran soluble component of the toner is Mn 2,00.
0~20,000. Mw is 50,000 to 5,000
,000, preferably 50,000 to 3.000.0
00 is better.

In the present invention, the values of My and Mu were calculated from values measured by gel permeable chromatography. The measurement conditions were as follows: Tetrahydrofuran was used as a solvent at a temperature of 25°C at a rate of 1III per minute! A sample solution of tetrahydrofuran with a sample concentration of 8 g/layer 2 was poured at a flow rate of 0.5 fat!
Inject and measure. In addition, as a column, 103-2
In order to accurately measure the molecular weight range of X106, it is recommended to combine multiple commercially available polystyrene gel columns, such as G-Styragej (manufactured by Waters) 5.
00.103.104.105 combination and 5hodex A-802, 803, 804, 805 manufactured by Showa Denko
When measuring the molecular weight of a sample that has a good combination of the following, the molecular weight distribution of the sample was calculated from the relationship between the logarithm value of a calibration curve prepared using several types of monodisperse polystyrene standard samples and the number of counts. As a standard polystyrene sample for creating a calibration curve, for example, Pressure Cbemic
aRCo, or Toyo Tsudani Gyo Co., Ltd. with a molecular weight of 6.
X 102.2. IX 103,4 X 103゜1.
75X 104.5. IX 104.1. IX 105
．． 3.9X 105゜8.6 X 105.2 X 1
It is appropriate to use at least 10 standard polystyrene samples of 0.6.4.48 x 106. Further, an R1 (refractive index) detector is used as a detector.

Further, in the kneaded and pulverized heat fixing toner, the tetrahydro-insoluble content of the resin component in the toner is 70 wt% or less, preferably 10 to 60 wt%, more preferably 10 wt% or less.
When the amount is 50 wt%, the compound of general formula (I) used in the present invention is well dispersed in the toner, and the charge control effect is effectively exhibited. When the tetrahydrofuran insoluble content is less than 10 wt%, the compound used in the present invention is poorly dispersed, resulting in uneven toner particles, poor durability, and problems such as a decrease in density and fogging during use may occur. . Moreover, when it exceeds 70 wt%, there are disadvantages such as problems in manufacturing such as poor fixing and insufficient crosstalk when using a kneading method.

In the present invention, the tetrahydrofuran insoluble content is the proportion of a portion of the polymer that has become insoluble in a solvent. The tetrahydrofuran-insoluble content is defined by the value measured as follows. In other words, the toner is kept at a constant weight (%ll)
+g) Weigh and use thimble filter paper (No. 86R manufactured by Toyosho Paper Co., Ltd.)
) using a Soxhlet extractor to remove the soluble components in the polymer with a solvent, and the sample remaining without being extracted is dried and weighed (Lg).

Let W3 be the weight of solid components such as magnetic material and silica contained in the toner, and the solvent-insoluble content is calculated as follows. For example, tetrahydrofuran is suitable as such a solvent, and extraction was carried out for about 6 hours here.

[Examples] Hereinafter, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited to these Examples. All parts in the following formulations are parts by weight.

Example 1 After premixing the above materials, they were kneaded with two rolls heated to 150°C, cooled, coarsely pulverized with a cutter mill, pulverized with a pulverizer using a jet stream, and further pulverized with a wind classifier. A fine powder having a volume average particle diameter of 100 ml was obtained by classification using a liquid crystal powder. This was thoroughly mixed with 0.4 part of hydrophobic colloidal silica to obtain toner No. 1. The physical properties of this toner No. 1 are shown in Table 1.

This toner was used for commercially available electronic copy 4m (product name MP-857).
0. When a continuous copying test of 30,000 sheets was conducted under normal conditions using a Canon product, images with high image density (1.3 to 1.35) and high resolution were stably obtained during the test. A similar test was also conducted at a low temperature and low humidity of 15°C and 10% RH.

A good image with no charge-up phenomenon, a stable high image density (1.30 to 1.35), and no fog was obtained. The amount of charge is determined by accurately weighing 1 g of toner and 9 g of iron powder carrier (200/300 mesh), mixing thoroughly, and blow-off (TB-200 manufactured by Toshiba Chemical Co., Ltd.).
).

Example 2 Toner No. 2 with a volume average particle diameter of 12 endometrium was obtained in the same manner as in Example 1 except for using the above materials, using an extruder as the crosstalk device. Table 1 shows the physical properties of toner No. 2.

Commercially available laser beam printer (product name LBP-OX
When a printout test was conducted using a Canon product, an image with high resolution and high image density (~1.30) was obtained. Furthermore, 15℃, 10%RH, 35℃, 80%RH
A similar test below yielded similar results.

Example 3 Toner No. 3 having a volume average particle diameter of 12 ml was obtained in the same manner as in Example 1 except that the above materials were used. Toner No.
The physical properties of No. 3 are shown in Table 1.

) +-No, 3 Commercially available copy a (Product name NP-25
As a result of a continuous copying test of 30,000 sheets under normal conditions with 0RE (manufactured by Canon), the image density (~1
．． A fog-free image with high 4) was obtained. 1 more
In similar tests under each environment of 5° C., 10% RH, 135° C., and 80% RH, excellent images similar to those under the normal environment were obtained.

Example 4 Toner N014 was obtained in the same manner as in Example 1 except for using the above materials. Table 1 shows the physical properties of toner N084.

The toner was mixed at a ratio of 5 parts to 100 parts of ferrite carrier having an average particle size of 50 to 80 μm to prepare a developer. This is a commercially available electronic copy a (product name NP-5000)
When a continuous copying test of to and ooo sheets was carried out using a Canon printer, fog-free blue images were stably obtained. Furthermore, when similar tests were conducted under the following environments: 15° C., 10% RH, and 30° C., 90% RH, good images were obtained as in the normal environment.

Comparative Example 1 Toner N015 having a volume average particle size of 11.5 parts was obtained in the same manner as in Example 1, except that 2 parts of the following monoazo compound chromium complex was used instead of compound (1). Toner No.
The physical properties of No. 5 are shown in Table 1.

As a result of carrying out the same copying test as in Example 1, good images were obtained under normal conditions, but at 15°C and 10% R.
Under the low temperature and low humidity environment of H, a charge 7 rise phenomenon occurred, the image density was low (1.0 to 1.1), and fogging also occurred.

Comparative Example 2 Toner N026 having a volume average particle size of 11.5 gm was obtained in the same manner as in Example 2, except that 0.5 part of the following monoazo compound chromium complex was used instead of compound (2). Toner N
The physical properties of o and 6 are shown in Table 1.

As a result of carrying out the same copying test as in Example 2, almost good images were obtained under normal conditions, but at 35°C and 80%
Under the high temperature and high humidity environment of RH, the image density decreased to a certain extent (1.0 to 1.05) that was problematic in practice.

[Effects of the Invention] The toner of the present invention can be used for developing electrostatic charge images in electrophotography, electrostatic recording, electrostatic printing, etc. by any conventionally known means. It produces such excellent effects.

■ Decrease in image density, which becomes a problem in low humidity environments, etc.
A charge-up phenomenon accompanied by fog etc. does not occur, and good images can be stably obtained.

■ Good images with high image density can be obtained even under high humidity conditions.

- Good images with high image density and no fogging can be obtained regardless of whether it is used in low-speed or high-speed machines with different copying speeds.

■ It has excellent resolution and line reproducibility, and is advantageous for digital development, which requires high resolution.

■ Since it has low tinting power, it can also be used in color toners.

Claims (1)

[Claims] (1) For 100 parts by weight of the resin component, apply the following general formula (
A toner for developing electrostatic images, characterized in that it contains 0.01 to 10 parts by weight of the compound represented by I). ▲There are mathematical formulas, chemical formulas, tables, etc.▼(I) [In the formula, R_1 is ▲There are mathematical formulas, chemical formulas, tables, etc.▼(
R^4 represents alkyl or alkenyl having 1 to 18 carbon atoms, or aralkyl or aryl which may have a substituent on the aromatic ring, and R^2 and R^3 represent hydrogen, halogen, nitro, carbon Represents 1 to 18 alkyl, alkenyl, aralkyl, aryl, or alkoxy, and X and Y are -O-, -COO-, -S-, or -N
R^5- (R^5 is hydrogen or alkyl having 1 to 4 carbon atoms), M represents scandium, titanium, vanadium, manganese, nickel or zinc, A is hydrogen,
It represents sodium, potassium, ammonium or organic ammonium, and l, m and n represent 1 or 2. In addition, when it has multiple substituents, each may be the same or different. ]