JPS6396664A - Toner composition - Google Patents

Abstract

PURPOSE:To prevent a powder toner from filming due to a metal salt and melt attaching in streaks to the surface of a photosensitive body at the time of cleaning by incorporating a fatty acid metal salt in the powder toner in an amount of <=0.5wt% of the toner, and further an abrasive and an electric resistance regulator. CONSTITUTION:The powder toner composed of a binder resin and a colorant further contains the fatty acid metal salt, such as zinc stearate, in an amount of <=0.5wt% of the total weight of the toner. Since a small amount of the toner is used, filming due to the toner is avoided, and an abrasive, such as silica, is added in an amount of 0.05-3wt%, thus permitting filming, if it happens, to be removed by polishing, and melt attaching of the toner in streaks to the surface of the photosensitive body at the time of cleaning to be prevented. Moreover, a regulator for controlling the electric resistance of the toner and a developer is added in an amount of 0.05-0.3wt%, permitting image density and image characteristics to be regulated, and a high-quality image to be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a toner composition, and more particularly, to a toner composition for developing an electrostatic charge image formed in an electrophotographic method, an electrostatic printing method, an electrostatic recording method, etc. The present invention relates to a toner composition.

<Prior art> Conventionally, in copying machines using electrophotography, colorants, binders, etc. Various toners containing resin and the like are used.

In the dry development method, an electrostatic image formed on the photoreceptor by charging and exposure to light is developed with the toner, and the developed toner image is transferred to a support such as transfer paper, and a heating roller or pressure roller The toner image is fixed on the support and the electrostatic charge image is visualized. Further, after the toner image is transferred to the support, the remaining toner on the photoreceptor is scraped off by a cleaning blade in order to clean the toner remaining on the photoreceptor. When this cleaning step is repeated, the toner is fused to the photoreceptor and gradually grows due to frictional heat between the photoreceptor surface and the cleaning blade. In particular, if the photoconductor is not smooth or if there are protrusions or holes on the photoconductor, damage to the photoconductor will increase and toner will tend to adhere to the surface of the photoconductor in the form of streaks. In combination, there are problems such as toner streaks appearing on the copied image and degrading the quality of the copied image.

In order to solve the above-mentioned problems, it is known that the above-mentioned toner is added with a fatty acid metal salt that protects the photoreceptor and improves cleaning properties, and an abrasive substance such as hydrophobic silica (Japanese Patent Publication No. 54 -16220, JP-A-58-125045).

<Problems to be Solved by the Invention> However, although the photoreceptor can be protected by adding the fatty acid metal salt, especially when the photoreceptor has an organic photosensitive layer, the fatty acid metal salt Since it has a high affinity with the photoreceptor, the fatty acid metal salt tends to form a film on the surface of the photoreceptor. When the fatty acid metal salt forms a film, the quality of the copied image etc. deteriorates because the filmed fatty acid metal salt functions as an insulating layer and the surface potential of the photoreceptor having the organic photosensitive layer is generally low. There was a problem with the decline.

Furthermore, if a large amount of the fatty acid metal salt is added in order to improve image characteristics such as gradation, not only will the above-mentioned filming occur, but the electrical resistance of the toner and developer will decrease, resulting in solid areas in the image. There is a problem in that toner smear occurs in the vicinity and the quality of copied images etc. deteriorates. Furthermore,
Since the organic photosensitive layer of the photoreceptor is softer than the photosensitive layer made of selenium or the like, when a toner containing an abrasive substance such as hydrophobic silica is used, the organic photosensitive layer is polished by the abrasive substance. There was a problem that it became unusable at an early stage.

Purpose> The present invention has been made in view of the above problems, and even when a photoreceptor having an organic photoreceptor layer is used as a photoreceptor, it protects the photoreceptor and prevents toner from forming on the surface of the photoreceptor. It is possible to form high-quality images by preventing streak-like fusion and adjusting the electrical resistance of toner and developer without deteriorating the photosensitive characteristics of the photoreceptor or the characteristics of toner and developer. An object of the present invention is to provide a toner composition.

Means and operation for solving the problems> The present invention has the following features:
In a powder toner containing a binder resin, a colorant, and other additives, where X is the weight part of fatty acid metal salt added to 100 parts by weight of this toner, X satisfies the following relational expression, and 0 < x ≦0.01 (ffrQ
Part) The above-mentioned conventional problems are solved by a toner composition to which an abrasive substance and an electrical resistance modifier are added.

According to the toner composition of the present invention having the above-mentioned structure, the amount of fatty acid metal salt added is small, and it is possible to suppress the formation of fatty acid metal salt on the surface of the photoreceptor. Even if this occurs, the abrasive substance polishes the fatty acid metal salt film and cleans it, so the photoreceptor can be protected and the toner will not form streaks on the photoreceptor surface when cleaning the photoreceptor. Can prevent fusion. Furthermore, since the amount of the fatty acid metal salt added is small, the electrical resistance of the toner and developer hardly decreases, and the characteristics of the toner and image characteristics are not adversely affected. Furthermore, the addition of an abrasive substance not only improves the fluidity of the toner, and by extension the toner's charging characteristics and image characteristics, but also the addition of an electrical resistance adjuster makes it possible to adjust the electrical resistance of the toner and developer. , image characteristics are improved.

The present invention will be explained in detail below.

The toner composition of the present invention comprises a powder toner containing a binder resin, a colorant, and other additives, and a fatty acid metal salt, an abrasive substance, and an electrical resistance modifier added to the toner.

Examples of the binder resin include styrene polymers, acrylic polymers, styrene-acrylic copolymers, polyethylene, chlorinated polyethylene, polypropylene, olefin polymers such as ionomers, polyvinyl chloride, polyester, polyamide, and polyurethane. , epoxy resin, diallyl phthalate resin, silicone resin, ketone resin, polyvinyl butyral resin, phenol resin, rosin-modified phenol resin, xylene resin, rosin-modified maleic acid resin, rosin ester, petroleum resin and the like.

The unsaturated monomers used in the above polymer include styrene, α-methylstyrene, 0-methylstyrene, p-
Styrenic monomers such as methylstyrene, p-methoxystyrene, p-chlorostyrene; acrylic acid, methyl acrylate, ethyl acrylate, n-butyl acrylate,
Isobutyl acrylate, 〇-octyl acrylate, 2-ethylhexyl acrylate, dodecyl acrylate,
Stearyl acrylate, cyclohexyl acrylate, phenyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, glycidyl acrylate, diethylaminoethyl acrylate, acrylamide, acrylonitrile, methacrylic acid, methyl methacrylate, methacrylic acid Ethyl, n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, 2-ethylhexyl methacrylate, dodecyl methacrylate, stearyl methacrylate, cyclohexyl methacrylate, phenyl methacrylate, glycidyl methacrylate, methacrylate Acrylic or methacrylic monomers such as 2-hydroxyethyl, 2-hydroxypropyl methacrylate, and diethylaminoethyl methacrylate; unsaturated double bonds such as maleic acid, fumaric acid, crotonic acid, itaconic acid, or their alkyl esters Carboxylic acid or alkyl ester thereof; Olefinic monomers such as ethylene, propylene, butadiene;
Examples include vinyl acetate; vinyl chloride; vinylidene chloride, vinylpyrrolidone, and vinylnaphthalene. The above monomers may be used singly or in a mixture of two or more.

Among the above polymers, those whose main component is a styrene polymer, an acrylic polymer, a styrene-acrylic copolymer, or the like are preferred. These polymers have a weight average molecular weight of ao, ooo to 200.000, especially 50.000.
-150,000 is preferable, and one type or a mixture of two or more types can be used.

Among the above polymers, rosin esters, rosin-modified phenolic resins, rosin maleic acid resins, epoxy resins, polyesters, cellulose polymers, polyether resins, etc. are useful for improving the triboelectric properties of toner. Useful.

Further, when the toner is a heat fixable toner, the above polymer has a softening point of 50 to 200°C, preferably a softening point of 70 to 200°C.
It is preferable to keep the temperature at 170°C overnight.

In addition, when the toner is a pressure fixable toner, olefin polymers such as polyethylene and polypropylene, etc.
Polymers that are easily plastically deformed are mainly used. This polymer can be used with other polymers, such as polyvinyl acetate, ethylene-vinyl acetate copolymer, hydrogenated polystyrene, hydrogenated rosin ester, aliphatic, alicyclic or aromatic petroleum It may contain resin or the like.

Examples of the coloring agent include carbon black, lamp black (C, 1, 7726B), chrome yellow (C, 1, 14090), Hansa yellow (C, IJkllL880, 11680, etc.), benzidine yellow. (C, 1, pick-up 21100, etc.)
, Suren Yellow G (C, 1, flk70600”)
, Quinoline Yellow (C, 1, 47005),
Permanent Orange GTR (C, 1, 臘12305
), Pyrazolone Orange (C, 1, Warehouse 21110'
), Palkan Orange (C, IJjL21160)
, Watch Young Red (C, 1, m 15865),
Permanent Red (C, 1, 12310, etc.), Brilliant Carmine 3B (C, lJh 16105), Brilliant Carmine 6B (C, 1, 151150),
DuPont Oil Red (C, 1, Chen 28105),
Pyrazolone Red (C,1,N121120), Lysol Red (C,1, Yang 1563G), Rhodamine B Lake (C,IJ145170), L/-Kylerad C (C,I.

Ljl15585), O-Zbengali (C,1,N
n45435), aniline blue (C, IJj150
405), Ultramarine Blue (C, 1, 7710
3), Calco Oil Blue (C, 1, Fjl aZ
OeQ Blue 3), methylene blue chloride (C,1, 52015'), phthalocyanine blue (C,1, 74180), phthalocyanine green (C,1, 74260), malachide green oxalate (C,1Jl142000') etc,
or C,1,SolvcntYellow 60,
C,1,5olvont Red 27,C,1,5o
Examples include oil-soluble dyes such as lventBlue 35. These blue agents are used alone or in combination of two or more, and are used in an amount that provides a sufficient toner image density, for example, 1 to 30% by weight, preferably 2 to 20% by weight.

Further, when the toner is a magnetic toner, a magnetic material is used together with or in place of the colorant. The above-mentioned magnetic material may be any material that exhibits magnetism or is magnetizable, such as iron such as ferrite and magnetite, metals or alloys that exhibit ferromagnetism such as cobalt, nickel, and manganese, or these metals. Examples include compounds containing the following. These magnetic materials have an average particle size of 0.1 to
It has a size of 1 μm, and is usually 20 to 75% by weight, preferably 40 to 70% by weight.
% by weight is used.

In order to control the charge of the toner for developing electrostatic images, the toner may contain a charge control agent as other additives, for example,
Oil-soluble dyes such as nigrosine dye (C, IJ, Beni 50415B), oil black (C, IJ128150), spirone black, naphthenic acid, salicylic acid, octylic acid, fatty acids mentioned below, resin acids such as manganese, iron, cobalt, and lead. , metal soaps that are metal salts of zinc, cerium, calcium, nickel, etc., metal-containing azo dyes, pyrimidine compounds, alkyl salicylic acid metal chelates, etc., containing 0.1 to 5% by weight based on the binder resin. is preferred.

In order to prevent the toner from adhering to the ankle roller, the toner may contain an anti-offset agent, such as various waxes such as low molecular weight polypropylene, low molecular weight polyethylene, and paraffin wax, and olefin monomers having 4 or more carbon atoms. Low molecular weight olefin polymers, fatty acid amides, silicone oils, etc., are added in amounts of 0.5 to 15% per toner.
Preferably, it contains ffim%.

A fatty acid metal salt is added to the powder toner in order to protect the photoreceptor and obtain a high-quality image without degrading developer properties.

The fatty acids of the fatty acid metal salts include saturated or unsaturated fatty acids having 8 to 36 carbon atoms, such as caprylic acid, capric acid, undecylic acid, lauric acid, tridecylic acid, myristic acid, valmitic acid, stearic acid, behenic acid, Lignoceric acid, cerotic acid, montanic acid, oleic acid,
Examples include elaidic acid, linoleic acid, lylunic acid, erucic acid, lysyllic acid, dihydroxystearic acid, cyclic fatty acids, dibasic acids, and dimer acids that are dimers of the above unsaturated fatty acids. Among the above fatty acids, saturated fatty acids, particularly stearic acid, are preferred.

Further, examples of the metal of the fatty acid metal salt include various metals such as zinc, lead, iron, copper, tin, cadmium, aluminum, calcium, magnesium, nickel, cobalt, manganese, lithium, and barium. Among the above metals, zinc is preferred. Among fatty acid metal salts, zinc stearate is particularly preferred because it has about 5 times the effect as aluminum stearate and the like.

The fatty acid metal salt is preferably in an amount such that, where X is the part by weight added of the fatty acid metal salt to 100 parts by weight of the powder toner, X satisfies the following relational expression: 0<x≦0.01 (parts by weight) , 0.001 to 0.01 parts by weight.

If the fatty acid metal salt is not added, the photoreceptor cannot be sufficiently protected, and streaks occur in copied images due to toner adhesion on the surface of the photoreceptor, resulting in a decrease in image quality. If the amount exceeds 0.01 part by weight, the fatty acid metal salt will form a film on the surface of the photoreceptor, and images will tend to be blurred, which is not preferable.

Further, an abrasive substance is added to the toner. The abrasive substance may be one that can polish the film to clean the photoreceptor when a film is formed by the fatty acid metal salt, and that does not adversely affect the characteristics of the toner, the photoreceptor, or the image. Any material can be used, such as talc, kaolin, barium sulfate, etc., but aluminum silicate, surface-treated aluminum silicate, titanium dioxide, calcium carbonate, antimony dioxide, barium titanate, calcium titanate, Strontium titanate, magnesium oxide, calcium silicate, zinc oxide, zirconium oxide, etc. are preferred, particularly,
Colloidal silica and surface-treated hydrophobic silica are preferred. With the addition of the abrasive substances mentioned above, in particular hydrophobic silica,
The fluidity of the toner and developer also improves, and the charging characteristics and image characteristics of the toner are improved. The abrasive material preferably has an average particle size of 5 to 100 mμ, particularly 10 to 30 mμ. If the particle size of the abrasive substance is outside the above range, the above effects will be reduced, which is not preferable.

A preferred specific example of the above-mentioned abrasive materials is "Aerosil R972J (average particle size 1 [
imμ), etc. can be exemplified.

The abrasive substance is preferably added in an amount of 0.05 to 0.3 parts by weight per 100 parts by weight of the powder toner.

When the amount of the abrasive substance added is less than 0.05 ffi parts,
The fluidity of the toner is poor, and if it exceeds 0.3 parts by weight, the photoreceptor tends to be easily damaged.

Further, an electrical resistance adjusting agent is added to the powder toner in order to adjust the electrical resistance of the toner and developer, image characteristics such as gradation, density, etc., and obtain a high quality image.

As the electric resistance adjusting agent, any substance can be used as long as it adjusts the electric resistance of the toner and does not adversely affect the characteristics of the toner, the photoreceptor, or the image.
For example, carbon black or the like may be used, but aluminum oxide, which allows fine adjustment of electrical resistance, is preferable.

The electrical resistance adjuster preferably has a particle size similar to that of the abrasive substance, and examples thereof include "Aluminum Oxide C" (average particle size: 20 mμ) manufactured by Nippon Aerosil Co., Ltd.

It is preferable to add 0.05 to 0.3 parts by weight of the electrical resistance:A adjuster to 100 parts by weight of the powder toner. If the amount of the electrical resistance adjuster added is less than 0.05 parts by weight, fine adjustment of electrical resistance becomes difficult. Also, 0.3
If the amount exceeds the ffl amount, image blurring tends to occur.

In order to improve the fluidity of the toner, the surface of the toner may be treated with a compound having low surface tension such as a silane coupling agent, silicone, or a fluorine compound. Furthermore,
If desired, the two pairs of powder toners may be heat-treated to make the corners and the like of the toner smooth in order to improve the fluidity of the toner.

The above powder toner has a particle size of 1 to 30 μm, preferably 5 μm.
~25 μm.

The toner composition of the present invention is useful as either a one-component toner or a two-component toner. Note that when used as a -component toner, the toner containing the above-mentioned magnetic material is used alone as a developer, and when used as a two-component toner, it is mixed with a carrier such as iron powder or glass beads and used as a developer. . In addition, as the above-mentioned carrier, glass beads,
Uncoated curers such as oxidized or unoxidized iron powder, or coated carriers in which magnetic materials such as iron, nickel, cobalt, and ferrite are coated with polymers such as acrylic polymers, fluorine polymers, and polyesters, are used. Usually 50-20
It has a particle size of 00 μl. Furthermore, when using a developer consisting of the above toner and carrier, the toner usually contains 2
~15ffim% is used.

The photoreceptor may include selenium, selenium-tellurium,
Photoreceptors such as zinc oxide, cadmium sulfide, and amorphous silicon can also be used, but organic photoreceptors such as selenium
Polyvinylcarbazole (PVK) 71 photoreceptor, polyvinylcarbazole and 2,4,7-dolinitrofluorenone or tetracyano-p-quinodimethane (TCN
When using an organic photoreceptor such as a photoreceptor consisting of Q) or a photoreceptor containing a photosensitive hm compound having a heterocyclic ring, a condensed ring, etc. in the polymer, the toner composition of the present invention is particularly suitable for:
suitable.

The above-mentioned toner composition can be prepared by a conventionally known developing method, for example, -
When the toner is a component toner, it is developed by a bristle brush development method, a magnetic brush development method, or a powder cloud development method, and when it is a two-component toner, it is developed by a cascade development method, a magnetic brush development method, or the like.

A method for producing the toner composition of the present invention will be briefly described below. First, a powder toner containing a binder resin, a colorant, etc. is manufactured. This powder toner is produced by a conventionally known method, for example, by mixing and dispersing the stone resin and a coloring agent using a heated mixer such as a hot roll or an extruder, and then pulverizing it using a pulverizer such as a hammer mill or jet mill. In addition, it is manufactured by a mechanical pulverization method in which particles are classified using a classifier to obtain a predetermined particle size, or a spray drying method in which the colorant, etc. is dispersed in a solution of the binder resin and spray-dried to a predetermined particle size. be able to. Then, by adding a predetermined amount of the fatty acid metal salt, abrasive substance, and electrical resistance adjuster to the toner and uniformly mixing them using an appropriate mixer such as a ball mill or a V-type mixer, the toner of the present invention can be prepared. A composition can be manufactured.

<Examples> The present invention will be described in more detail below based on Examples.

Example 1 90% by weight of styrene-acrylic copolymer as a binder resin, 7.5% by weight of carbon black as a colorant, 1.5% by weight of polypropylene as an anti-offset agent,
A powder toner having an average particle size of 5 to 20 μm was prepared by a conventional method using 1.0% by weight of nigrosine dye as a charge control agent. To 100 parts by weight of this toner, zinc stearate was added in the proportions shown in Table 1, and 0.2 parts by weight of hydrophobic silica (Aerosil R972J, manufactured by Nippon Aerosil Co., Ltd.) and aluminum oxide (aluminum oxide) were added to 100 parts by weight of this toner. C", manufactured by Nippon Aerosil Co., Ltd.) 0.
2 parts by weight were added and mixed uniformly to prepare a toner composition.

Further, 4.5 fflffi% of the above toner composition and 95.5% by weight of ferrite carrier having an average particle size of 50 to 80 μm were uniformly mixed in a ball mill to prepare a developer.

Using the above developer, the development characteristics were investigated using a copying machine (modified model DC-1ll manufactured by Sanda Kogyo Co., Ltd.) equipped with a photoreceptor having an organic photosensitive layer, and the results shown in Table 1 were obtained. Obtained.

As is clear from the results in Table 1, if zinc stearate is not added, the toner will fuse to the photoconductor, and if the amount added is 0.03 parts by weight or more, the film will not adhere to the photoconductor. Mining occurs. On the other hand, it has been found that when the amount of zinc stearate added is 0.01 ffl m parts or less, toner fusion to the photoreceptor, filming, and image bleeding do not occur. In addition, when the toner was fused to the photoreceptor, black streaks surrounding the fused toner were observed in the image.

Example 2 0.01 parts by weight of zinc stearate and 0.2 parts by weight of aluminum oxide of Example 1 were added to 100 parts by weight of the powder toner of Example 1, and the hydrophobic silica of Example 1 was added. Each of these components was added in the proportions shown in Table 2 to prepare a toner composition. The image characteristics were examined in the same manner as in Example 1, and the results shown in Table 2 were obtained.

As is clear from Table 2, when no hydrophobic silica is added, the toner has poor fluidity, and when the amount of hydrophobic silica added is 0.4 parts by weight or more, the photoreceptor may be damaged. , it was not possible to protect the photoreceptor. On the other hand, when the amount of hydrophobic silica added is 0.05 to 0.3 parts by weight, the toner has good fluidity and can protect the photoreceptor, as well as prevent the toner from forming on the surface of the photoreceptor. There was no fusion and the image characteristics were excellent.

(Hereinafter, blank space) Example 3 0.01 part by weight of zinc stearate and 0.01 part by weight of the hydrophobic silica of Example 1 were added to 100 parts by weight of the powder toner of Example 1.
．． 2 parts by weight was added, and the aluminum oxide of Example 1 was added in the proportions shown in Table 3 to prepare a toner composition. The image characteristics were examined in the same manner as in Example 1, and the results shown in Table 3 were obtained.

As is clear from Table 3, the toner without aluminum oxide had poor fluidity, and the amount added was 0.4
When the amount exceeds 1 part by weight, the fluidity of the toner decreases, the photoreceptor is scratched, and images are smeared. On the other hand, when the amount of aluminum oxide added was 0.05 to 0.3 parts by weight, the toner had good fluidity, no damage to the photoconductor, no blurring of the image, and good gradation. Excellent images were obtained. It has been found that as the amount of aluminum oxide added increases, the electrical resistance value of the developer decreases, and that the electrical resistance of the toner can be adjusted by changing the amount of aluminum oxide added.

<Effects of the Invention> As described in 2 below, in the toner composition of the present invention, the amount of fatty acid metal salt added is small, and the fatty acid metal salt is difficult to form a film on the surface of the photoreceptor. 1. Even if filming occurs due to bipedal fatty acid metal salts, the abrasive substance polishes and cleans the film of fatty acid metal salts, so the photoreceptor can be protected and when cleaning the photoreceptor. It is also possible to prevent the toner from fusing in the form of streaks on the surface of the photoreceptor. Furthermore, since the amount of the fatty acid metal salt added is small, the electrical resistance of the toner and developer is almost reduced, and the toner characteristics and image characteristics are not adversely affected. Furthermore, the addition of an abrasive substance not only improves the fluidity of the toner, and by extension the toner's charging characteristics and image characteristics, but also the addition of an electrical resistance adjuster makes it possible to adjust the electrical resistance of the toner and developer. This invention has an effect unique to the present invention in that high-quality images can be obtained.

Claims (1)

[Claims] 1. In a powder toner containing a binder resin, a colorant, and other additives, when x is the weight part of fatty acid metal salt added to 100 parts by weight of this toner, x satisfies the following relationship. A toner composition that satisfies the formula: 0<x≦0.01 (parts by weight) and further contains an abrasive substance and an electrical resistance regulator. 2. The toner composition according to claim 1, wherein the fatty acid metal salt is zinc stearate. 3. Claim 1 above, wherein the abrasive substance is silica.
The toner composition described in . 4. The abrasive substance is 0.0 parts by weight per 100 parts by weight of toner.
The toner composition according to claim 1 or 3, wherein 5 to 0.3 parts by weight is added. 5. The toner composition according to claim 1, wherein the electrical resistance adjuster is aluminum oxide. 6. The electrical resistance adjuster is added to 100 parts by weight of the toner,
The toner composition according to claim 1 or 5, wherein 0.05 to 0.3 parts by weight is added.