JPS6214166A - Magnetic toner - Google Patents

Abstract

PURPOSE:To obtain a magnetic toner good in magnetic characteristics, and capable of forming a fogless superior image fixed without accompanying any offset trouble by incorporating a specified magnetic powder and a specified releasing agent in a binder resin. CONSTITUTION:The magnetic toner is prepared by incorporating the magnetic powder containing 50-100wt% metallic iron, and a releasing agent selected from a group of (A) fatty acid ester wax, (B) partially saponified fatty acid ester wax, (C) fatty acid amide wax, and (D) higher fatty acid wax, and other necessary toner components in the binder resin. The releasing agent is added in an amount of 1-10wt%, and if it is <1wt%, an effect as a releasing agent is not exhibited, and accordingly, the offset trouble cannot sufficiently be prevented. On the other hand, if it is >10wt%, the fluidity of the magnetic toner drops, resulting in deteriorating both of developability and transferability, and hardly forming a good image.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a magnetic toner for developing latent images formed in electrophotography, electrostatic printing, electrostatic recording, magnetic recording, etc. It is something.

[Conventional technology]

At present, as a method for forming a visible image based on image information, a method using an electrostatic latent image or a magnetic layer image is widely used. Quiet? In the method using an ITL image, an electrostatic latent image is formed based on the given image information, and this is developed with a developer.The resulting toner image is usually transferred to transfer paper and fixed to form a visible image. Form.

Powder developers are preferred as developers for developing electrostatic latent images in such image forming methods because of their ease of handling. Powder developers are two-component developers, which are made by mixing a toner containing binder resin particles with a colorant, etc., and a carrier made of iron powder, glass beads, etc., and binder resin particles. It can be roughly divided into so-called one-component developers, which are made only of magnetic toner containing powder of magnetic particles, etc., and are used without being mixed with a carrier.The latter one-component developer The developer is preferable because it essentially does not have the problem of the toner concentration changing with use, unlike the two-component developer.

Conventionally, magnetic toners are usually composed of powder of magnetic particles made of iron oxide such as magnetite and other toner components dispersed in a binder resin.

[Problem that the invention seeks to solve]

However, such magnetic particles made of iron oxides such as magnetite are usually black, and therefore, even if they contain a chromatic coloring agent, their chromatic color development is low, and as a result, color magnetic toners with a wide variety of colors are produced. is difficult to obtain.

On the other hand, technical means to reduce the content ratio of magnetic particles made of iron oxide such as ill magnetite, (2) technical means to contain a large amount of chromatic coloring agent, (3) T-hematite, It is conceivable to adopt technical means such as using magnetic particles having a hue other than black, such as ferrite.

However, with the above technical means t1), the magnetic particles made of iron oxide such as magnetite have a small magnetization ability, so it is not possible to obtain the magnetic properties necessary for a magnetic toner, and as a result, the resulting image is fogged. However, in the technical means (2) above, chromatic colorants are usually used for dyeing.
If a large amount of this is contained in the toner particles, the softening point of the toner will increase, and the fixing performance will deteriorate during heat fixing of the toner image. Although it is possible to form an image exhibiting such a chromatic color using a film containing a sepia or red chromatic coloring agent with the technical means described in 3), it is possible to form an image exhibiting such a chromatic color using other chromatic colors such as green. However, it is difficult to obtain a magnetic toner that can produce a wide variety of colors, which limits the colors of the images that can be obtained, and increases the cost when using ferrite. It is difficult to obtain color magnetic toners that can form color images.

In addition, in the fixing process, a heat roller fixing method is widely adopted because it has high thermal efficiency and is advantageous compared to other methods. There is a tendency for the so-called offset phenomenon to occur, in which the toner is transferred to the surface of the roller and transferred again to the next transferred transfer paper, staining the image.

However, in the case of color toners, chromatic colorants are generally more difficult to grind into small-diameter particles than the carbon blank normally used for black toners, and their compatibility with binder resins is also low. , the dispersibility of the chromatic colorant in the binder resin tends to be insufficient, and therefore it is difficult to obtain sufficient color density and hiding ability.In contrast, toner particles are used to increase the color density and hiding ability of color toners. It may be possible to increase the content ratio of the chromatic colorant in the toner particles, but if this is done, chromatic colorant particles with a large particle size will be present at high density in the toner particles.
Not only does the toner particle become easily broken, but also the softening point of the toner increases, making it difficult to fix, and the elasticity of the toner decreases when melted, causing an offset phenomenon.

In addition, since the chromatic colorant generally has a larger particle size than the carbon blank in black toner, the surface smoothness of the color toner particles is inferior to that of black toner, and therefore the surface friction coefficient of the fixed color toner image is lower than that of black toner. It is generally larger than that of a toner image, so even if a color toner image and a black toner image are fixed to the transfer material with the same adhesion strength, the color toner image is more likely to be scratched than the black toner image. There is a problem that the toner image is easily removed and therefore the storage stability of the toner image after fixing is poor.

[Purpose of the invention]

The present invention has been made based on the above-mentioned circumstances, and an object thereof is to be able to form an image having good in-magnetic properties and without fog, and without causing an offset phenomenon. To provide a magnetic toner capable of forming an excellent fixed image, and also capable of sufficiently expressing the colors of a chromatic colorant to form a color image of various colors.

[Means for solving problems]

The magnetic toner of the present invention comprises a magnetic powder consisting of particles in which metallic iron is present in a proportion of 50 to 100% by weight in a binder resin, and a release material selected from the group shown in (a) to (d) below. It is characterized by containing an agent.

(a) Fatty acid ester wax (b) Partially saponified fatty acid ester wax (c) Fatty acid amide wax (d) Higher fatty acid wax According to this structure, since the magnetic powder is a specific material, the magnetizing ability is large. Good in-magnetic properties can be obtained, and since the magnetic toner particles contain a specific release agent, the toner has excellent non-offset properties and improves the smoothness of the toner particle surface. Therefore, the fixed image has sufficient strength against external mechanical forces such as abrasion, and since the magnetic powder itself is colorless or has a hue close to gray, chromatic colorants are used. When chromatic colorant is contained, the color corresponding to the content of the chromatic colorant will appear sufficiently.

The present invention will be specifically explained below.

In the present invention, 50% of metallic iron is contained in the binder resin.
A magnetic powder consisting of particles (hereinafter also simply referred to as "magnetic particles") present in a proportion of ~100% by weight, and the above (a)
A magnetic toner is constituted by containing a release agent selected from the group shown in (d) to (d) and other necessary toner components.

In the case of a color magnetic toner, the binder resin contains 50 to 100!1ffi9'6 of metallic iron.
a magnetic powder consisting of particles present in a proportion of , a release agent selected from the group shown in (a) to (d) above, a chromatic coloring agent, and other necessary toner components. to constitute color magnetic toner.

Note that particles in which metallic iron is present in a proportion of 50 to 100% by weight refer to particles in which the proportion of metallic iron as a compositional component is 50 to 100% by weight in one particle.

Here, "metallic iron" refers to the iron component itself, which does not form a compound with any other element other than iron.The ratio of metallic iron in the magnetic particles is 50 to 100%, but preferably 6%. If this ratio is less than 1%, the magnetic particles themselves will have a blackish hue, and therefore it will be difficult to form a color image with a variety of colors. It becomes difficult to obtain color magnetic toners that can be used.

The average particle size of the magnetic particles is preferably 31 or less, more preferably 1.5I or less. If this average particle size exceeds 3 ttm, it may be difficult to incorporate the magnetic particles in a well-dispersed state in the toner particles, and in this case, it may be difficult to obtain the magnetic properties necessary for a magnetic toner. It may disappear. The average particle size referred to here is "sub sieve sizer (Sub 5
ieve 5izer) J (manufactured by Fisher).

The magnetic particles preferably have a saturation magnetization of +30 emu/g or more in a magnetic field of 100,000 e, and when the saturation magnetization value is less than 130 emu/g, the toner is The content ratio of magnetic particles required in the particles increases, which may result in a decrease in fixing performance during thermal fixing of toner images.

The content ratio of magnetic particles in toner particles is 10 to 70
It is preferably % by weight, more preferably 20-20% by weight.
It is 55% by weight. If this proportion is less than 10% by weight, the necessary magnetic properties cannot be obtained, while if this proportion exceeds 70% by weight, the fixing performance during thermal fixing of the toner may deteriorate.

In the magnetic particles, compositional components other than metal iron include, for example, Fe1Oa, MOFezOz (however, HO is Ba, Co, Sr, Pb, Zn, Ni+Cu, Mn
, Li, and a combination of one or more of the following.

As a method for making the magnetic particles have 50 to 100% by weight of metallic iron as a compositional component, for example, a method of reducing an iron oxide containing iron element or an alloy thereof can be mentioned.

The binder resin in the magnetic toner is not particularly limited, and various resins can be used.

For example, when using a polyester resin as a binder resin, examples of the alcohol used to obtain the polyester resin include ethylene glycol, diethylene glycol, triethylene glycol,
．． Diols such as 2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, neopentyl glycol, 1,4-butynediol, 1.
Etherified bisphenols such as 4-bis(hydroxymethyl)cyclohexane, bisphenol A, hydrogenated bisphenol A, polyoxyethylenated bisphenol A1, polyoxypropylenated bisphenol A, and saturated or unsaturated bisphenols having 3 to 22 carbon atoms. Examples include divalent alcohol monomers substituted with hydrocarbon groups and other divalent alcohol monomers.

Carboxylic acids used to obtain polyester resins include, for example, maleic acid, fumaric acid, mesaconic acid, notraconic acid, itaconic acid, glutaconic acid, phthalic acid, isophthalic acid, terephthalic acid, cyclohexanedicarboxylic acid, succinic acid, adipine acids, cepatic acid, malonic acid, divalent organic acid monomers substituted with saturated or unsaturated hydrocarbon groups having 3 to 22 carbon atoms, anhydrides of these acids, lower alkyl esters, and luic acid. Examples include dimers and other divalent organic acid monomers.

In order to obtain a polyester resin used as a binder resin, it is preferable to use not only a polymer containing only the above difunctional monomer, but also a polymer containing a trifunctional or higher polyfunctional monomer component. be. Examples of trivalent or higher polyhydric alcohol monomers that are such polyfunctional monomers include sorbitol, 1,2.3.6-hexanetetrol, 1,4-sorbitan, pentaerythritol, and dipentaerythritol. , tripentaerythritol, sucrose, 1.2.4-butanetriol, 1,2.5-
Pentanetriol, glycerol, 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, trimethylolprohaf, t, 3. Examples include s-trihydroxymethylbenzene and others.

Examples of trivalent or higher polycarboxylic acid monomers include 1,2.4-benzenetricarboxylic acid, 1,2.5-benzenetricarboxylic acid, 1,2.4-cyclohexanetricarboxylic acid, 2.5-benzenetricarboxylic acid, and 2.5-benzenetricarboxylic acid. 7-naphthalenetricarboxylic acid, 1.2.4-naphthalenetricarboxylic acid, 1.2.4
-butanetricarboxylic acid, 1,2.5-hexanetricarboxylic acid, 1,3-dicarboxyl-2-methyl-2-
Examples include methylenecarboxypropane, tetra(methylenecarboxyl)methane, 1.2.7.8-octanetetracarboxylic acid, Empol trimer acid, acid anhydrides thereof, and others.

It is desirable that the above trifunctional or higher polyfunctional monomer component be contained in a proportion of 5 to 80 mol % in each of the alcohol component or acid component as a structural unit in the polymer.

Other resins that can be used as the binder resin include, for example, polymers or copolymers of monoolefin monomers or diolefin monomers. Examples of monoolefin monomers for obtaining such polymers or copolymers include styrene, 0-
Methylstyrene, m-methylstyrene, p-methylstyrene, α-methylstyrene, p-ethylstyrene, 2.
4-dimethylstyrene, p-n-butylstyrene, p-
terL-butylstyrene, p-n-hexylstyrene, p-n-octylstyrene, p-n-nonylstyrene, p-n-denlestyrene, p-n-dodecylstyrene, p-methoxystyrene, p-phenylstyrene, p-
Styrenes such as chlorostyrene and 3,4-dichlorostyrene; ethylenically unsaturated monoolefins such as ethylene, propylene, butylene, and isobutylene; vinyl halides such as vinyl chloride, vinylidene chloride, vinyl bromide, and vinyl fluoride Vinyl esters such as vinyl acetate, vinyl propionate, vinyl benzoate, vinyl butyrate; methyl acrylate, ethyl acrylate, acrylic 1
dn-butyl, isobutyl acrylate, propyl acrylate, n-octyl acrylate, dodecyl acrylate,
lauryl acrylate, acrylic M2-ethylhexyl,
stearyl acrylate, 2-chloroethyl acrylate,
Phenyl acrylate, methyl α-chloroacrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, isobutyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, methacrylate α-methylene aliphatic monocarboxylic acid esters such as lauryl acid, 2-ethylhexyl methacrylate, stearyl methacrylate, phenyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate; acrylonitrile, methacrylonitrile, Acrylic acid or methacrylic acid derivatives such as acrylamide; 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 isobropenyl ketone; N-vinylpyrrole ,
N-vinylcarbazole, N-vinylindole, N-
Examples include N-vinyl compounds such as vinylpyrrolidone; vinylnaphthalenes; and others.

Examples of the diolefin monomer include propadiene, butadiene, isoprene, chloroprene, pentadiene, and hexadiene.

These monoolefin-based monomers or diolefin-based monomers may be used alone, or may be used in combination, or may be combined to form a copolymer by polymerization. In this case, styrene-acrylic copolymer is particularly preferred.

Further, a crosslinked polymer obtained by reacting a crosslinking agent such as divinylhensen or divinylnaphthalene with the above monomer can also be used as the binder resin.

Other resins that can be used as the binder resin include, for example, epoxy resins. Composition components for obtaining epoxy resin include:
Examples include bisphenol A, epichlorohydrin, and others.

Among these, bisphenol A type epoxy resin is particularly preferred.

The release agent, which is an essential component in the magnetic toner according to the present invention, is selected from the group shown in (a) to (d) above, and may be used alone or in combination of two or more types. You may use a combination of things.

The content ratio of such a release agent is 1 to 1 with respect to the magnetic toner.
It is within the range of 0% by weight. If this proportion is less than 1% by weight, the effect as a mold release agent will not be exhibited, and therefore it will not be possible to sufficiently prevent the occurrence of offset phenomenon, and it will not be possible to obtain good fixing properties. If this ratio exceeds 1otit%, the fluidity of the magnetic toner will decrease, resulting in a decrease in developability and transferability, making it difficult to form a good image, and also causing development sleep or latency. The release agent adheres to the image support and forms a film, which inhibits its function.

Specific examples of such mold release agents are shown below.

(a) Fatty acid ester wax and (b) Partially saponified fatty acid ester wax A wax consisting of a fatty acid ester or a partially saponified product thereof having a melting point of about 30 to 130°C. Esters obtained by reacting unsaturated fatty acids with saturated or unsaturated aliphatic alcohols, or these esters, are combined with sodium, calcium, magnesium, lead,
It is obtained by partial saponification of metals such as aluminum, barium, and zinc with hydroxides.

Saturated or unsaturated fatty acids as raw material components may be either lower or higher, such as valeric acid, caproic acid, enanthic acid, caprylic acid, pelargonic acid, capric acid, undecylic acid, lauric acid, tridecylic acid, myristic acid, pentadecyl acid, palmitic acid,
Margaric acid, stearic acid, nondecylic acid, adipic acid, hehenic acid, lignoceric acid, cerotic acid, montanic acid, mellisic acid, hentriacontanonic acid, dotriacontanonic acid, tetratriacontanonic acid, hexatriacontanonic acid , octatriacontanonic acid, tuccinic acid, lindelic acid, lauroleic acid, tuzuic acid, myristoleic acid, seamaric acid, petroselic acid, oleic acid,
Elaidic acid, vaccenic acid, gadolenic acid, erucic acid,
Brassic acid, ceracoleic acid, linoleic acid, liluic acid, eleostearic acid, linoleaidic acid, valinaric acid, arachidonic acid, glutaric acid, adipic acid, pimelic acid, speric acid, azelaic acid, sebacic acid, and others with the number of carbon atoms Examples include dicarboxylic acids having 9 to 19 methylene groups.

In addition, saturated or unsaturated fats 111 which are other raw material components
Group alcohols may be lower or higher, and may be monohydric or polyhydric alcohols, such as methyl alcohol, ethyl alcohol, propyl alcohol, butyl alcohol, amyl alcohol, cabroyl alcohol, caprylic alcohol, and caprylic alcohol. , lauryl alcohol, myristyl alcohol, cetyl alcohol, stearyl alcohol, arachyl alcohol, behenyl alcohol, carnabil alcohol, seryl alcohol, coryanyl alcohol, myrinyl alcohol, methyl alcohol, rough ceryl alcohol, allyl alcohol, crotyl alcohol, 2 −
Buteno-1,2-penteno-1,3-hexeno-1,2-hebuteno-1,10-undecenol-1111-dobcenol-1,12-)lysocenol-1, oleyl alcohol, elaidyl alcohol,
Lilyl alcohol, Lilyl alcohol, ethylene glycol, propylene glycol, trimethylene glycol, 1,3-butanediol, 1゜4-butanediol, 2,3-butanediol, 2-phthene-1,4-diol, 1, 5-bentanediol, 2.4-bentanediol, 1,6-hexanediol, 2.5-hexanediol, 2-methyl-1,3-bentanediol,
2.4-heptanediol, 2-ethyl-L3-hexanediol, 2-ethyl-2-butyl-1,3-propanediol, hexadecane-1,2-diol, octadecane-1,2-diol, eicosane-1 , 2-diol, tocosan-1,2-diol, tetracosane-1
, 2-diol, diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, glycerin, pentaerythritol, sorbitol, and the like.

In addition, when either the fatty acid or the aliphatic alcohol is a lower class one, it is preferable that the other one is a higher class one.
Among these esters composed of fatty acids and aliphatic alcohols, the fatty acids have 5 carbon atoms.
The above are preferred, and esters having a total number of carbon atoms of 20 or more are more preferred.

These fatty acid ester waxes and partially saponified fatty acid ester waxes may be used alone or in combination of two or more.

That is, a mixture consisting of a composition in which two or more types of fatty acid ester waxes are mixed together, a mixture consisting of a composition in which a fatty acid ester wax and a partially saponified fatty acid ester wax are mixed together, or a mixture consisting of a composition in which two or more types of partially saponified fatty acid ester waxes are mixed together. It may be used as a mixture consisting of a mixed composition.

Commercially available fatty acid ester waxes and partially saponified fatty acid ester waxes include the following: Note that some of these commercially available products have a composition in which two or more types are mixed.

(lower alcohol ester of fatty acids) ``Butyl Stearate'' (manufactured by Yobin Fine Chemical Co., Ltd.) ``Butyl Stearate'' (Kao Soap Co., Ltd.) (polyhydric alcohol ester of fatty acids) ``Nissan Caster Wanox-AJ'' (NOF Corporation) ``Diamond Wax'' (manufactured by Shin Nihon Rika Co., Ltd.) ``Castor Hard'' (manufactured by Yobin Fine Chemical Co., Ltd.) (higher alcohol ester of fatty acids) Cetirno<Lumitate)
Ethylene glycol ester of montanic acid) "Hextowanox-OP" (manufactured by Hoechst Japan Co., Ltd., partially saponified product of butylene glycol ester of montanic acid) (partial ester of fatty acid and polyhydric alcohol) [Monogly-Ml (manufactured by NOF Corporation) , α-glycerol monostearate) "Fatty acid monoglyceride R-60J (manufactured by Matsumoto Yushi Pharmaceutical Co., Ltd., stearic acid monoglyceride) [Fatty acid monoglyceride R-80J (manufactured by Matsumoto Yushi Pharmaceutical Co., Ltd., oleic acid-stearic acid monoglyceride)""Rikemaru S- 200" (manufactured by Riken Vitamin Oil Co., Ltd., glycerin stearate) [Rikemar-13-100J (manufactured by Riken Vitamin Oil Co., Ltd.,
[Glycerin 7] hehenate) [Rike Maru S-300J (manufactured by Riken Vitamin Oil Co., Ltd., sorbitan monostearate) "Rike Maru PS-1004 (manufactured by Riken Vitamin Oil Co., Ltd.,
propylene glycol monosterolate) rATMUL-T-95J (manufactured by Kao Atlas Co., Ltd., high-purity monoglyceride) (mixed ester) rVLTN-4J (manufactured by Yobin Fine Chemical Co., Ltd.) r
'VLT-LJ (manufactured by Yubin Fine Chemical Co., Ltd.) rK
-3WaxJ (manufactured by Yobin Fine Chemical Co., Ltd.) "Rice wax" (manufactured by Noda Wax Co., Ltd.) "Carnauba wax" (manufactured by Noda Wax Co., Ltd.) (Han fatty acid amide wax From an alkylene bis fatty acid amide compound with a melting point of about 100 to 180 °C For example, waxes represented by the following structural formula can be cited as representative examples.

], C+oL+C0-NH-(C1lz)s-Nf
l-OCC+oL+2, Cl1)l! 3CONH(
CH) --Nll-OCC0Hx33, ClJi
tCO-NH-(CI(dz-NH-OCC+J low 74
．． 0. . +1! IcONH(CHx)i-NH-OCC
+Jtq5, C15lh+C0-N1+-Cost CHt
)x NH-OCC+sHs+6, ClJ3sC
ONi1-CH2N11-OCC+5H3s7, C
ltllssCO-NH-(C1lz)z-NH-OC
C+5Hff+8, CzJ4tCONH-Ctlz
-NH-OCC+sH3+12, Cz+L+C0-N
HCH2-NH-OCC! +841CzllsCO0C
C211s 14, CI? lI□Co-, NII (CHz)
s N11-OCC+Jz+ Incidentally, commercially available fatty acid amide waxes include, for example, the following.

"Bisamide" (manufactured by Nippon Hydrogen Industry Co., Ltd.) "Plastflow" (manufactured by Nitto Kagaku Co., Ltd.) "Diamid 200 Bis"
(manufactured by Nippon Hydrogen Industries Co., Ltd.) "Luburon EJ (manufactured by Nippon Hydrogen Industries Co., Ltd.)""Alflo H3O5J (manufactured by Nippon Oil & Fats Corporation)"
“Alflo V-60” (manufactured by NOF Corporation) “Amid-
6L” (manufactured by Yubin Fine Chemical Co., Ltd.) “Amide-7
3” (manufactured by Yubin Fine Chemical Co., Ltd.) “Amide-6H
” (manufactured by Yubin Fine Chemical Co., Ltd.) “Armorwax-EBSJ (manufactured by Lion Armor Co., Ltd.) “Hoechstowasox Cl (manufactured by Hoechst Japan Co., Ltd.)
"Nobuko Wanokusu 22DSJ (Nobuko Chemical Co. [Advax-280J (manufactured by Advance Co., Ltd.)]"
Kaohwanoxu EBJ (manufactured by Kao Soap Co., Ltd.), Varisin-285J (manufactured by Heker Castor Oil Co., Ltd.) (d) Higher fatty acid wax Higher fatty acid waxes include lauric acid, myristic acid, valmitic acid, stearic acid, oleic acid, linoleic acid, Waxes made of ricinoleic acid, arachidic acid, hehenic acid, lignoceric acid, ceracoleic acid, etc., or mixtures thereof can be mentioned.

In addition, as commercially available higher fatty acid waxes, the following can be mentioned, for example.

rF-3J (manufactured by Yubin Fine Chemical Co., Ltd.) rVLZ
-200J (manufactured by Yobin Fine Chemical Co., Ltd.) "Powdered stearic acid from cherry blossom, pine, bamboo, and camellia towns" (manufactured by NOF Corporation) "Beef tallow grade" (manufactured by NOF Corporation) rNAA 222J (manufactured by NOF Corporation) rNAA 2
21J (manufactured by NOF Corporation) rLunac S-40
J (manufactured by Kao Soap Co., Ltd.) rLunac S-90J
(manufactured by Kao Soap Co., Ltd.) rLunac S-30j (
(manufactured by Kao Soap Co., Ltd.) rLunac 8-55J (manufactured by Kao Soap Co., Ltd.) rLunac 8-95J (manufactured by Kao Soap Co., Ltd.)
rMY-85J (manufactured by Kao Soap Co., Ltd.) rMY-95J (Kao Soap Co., Ltd.!! rP-85J
(manufactured by Kao Soap Co., Ltd.) rP-95J (manufactured by Kao Soap Co., Ltd.) S-1 old (manufactured by Kao Soap Co., Ltd.) rS-204 <manufactured by Kao Soap Co., Ltd.] rT-3-2J (manufactured by Kao Soap Co., Ltd.) rT-3- 44 (manufactured by Kao Soap Company) rT-D-2J (manufactured by Kao Soap Company) rT-D-4J (manufactured by Kao Soap Company) "Kaoh Wax M-80J (manufactured by Kao Soap Company)""Kaoh Wax 85 Powder" (manufactured by Kao Soap Company) Kaowa 2x SSJ (manufactured by Kao Soap Co., Ltd.), Hoechstwax SJ (manufactured by Hoechst Japan Co., Ltd.) Chromatic colorants that can be used when the magnetic toner of the present invention is made into a color toner include various organic Pigments, inorganic pigments, and various chromatic dyes can be used, but organic chromatic pigments with clear colors and high light resistance and hiding properties are preferred.

Specifically, the following can be mentioned, for example. The exemplified substances below are from Color Index 3rd Edition 19.
71 C listed in the same supplement 1975, ! , name number,
and an example of the corresponding product name.

C01, Pigment Red 5 (Permanent Carmine FB, manufactured by Hoechst Japan Co., Ltd.) C,1, Pigment Red 48:1 (Sumika Print Red C1 manufactured by Sumitomo Chemical Co., Ltd.) C,1, Pigment Red 53:1 (Chromophthal Magenta G1 Ciba・Manufactured by Geigy) C, 1, Pigment Red 57:1 (Sumiyuki Print Carmine 6BC1 manufactured by Sumitomo Chemical) C,
1, Pigment Red 123 (Kayaset Red E-B, manufactured by Nippon Kayaku Co., Ltd.) C11, Pigment Red 139 (Kayaset Red E-GR, manufactured by Nippon Tohoku Co., Ltd.) C,! ,
Pigment Red 144 (Chromophthal Red BRN, manufactured by Ciba Geigy) C91, Pigment Red 149 (PV Fast Red B, manufactured by Hoechst Javan) C0
1, Pigment Red 166 (Chromophthal Scarlesoto R1 manufactured by Ciba Geigy) c, r, Pigment Red 177 (Chromophthal Red A3B, manufactured by Ciba Geigy) C, [, Pigment Red 178 (Kayaset Red H) -GG, made by Nippon Tohokusha) c, r
, Pigment Red 222 (Chromophthal Red Magenta G1 manufactured by Ciba Geiki) C11, Pigment Orange 3I (Chromophthal Orange 4R, manufactured by Ciba Geiki) C,1, Pigment Orange 43 (Hosta Palm Orange GR, manufactured by Hoechst) (manufactured by) C,1,
Pigment Yellow 17 (Fast Yellow GBFN, manufactured by Seizo Kagaku Co., Ltd.) C, 1
, Pigment Yellow 14 (Hengejin Yellow OT, DuPont? [)C, 1,
Pigment Yellow 138 (Variotol Yellow LO96011D, manufactured by Basf) C, I, Pigment Yellow 93 (Chromophthal Yellow 3G, manufactured by Ciba Geiki) C, 1, Pigment Yellow 94 (Chromophthal Yellow 6G, Ciba Geigy) Company!
! RiC,! , Pigment Green 7 (Chromophthal Green GF, manufactured by Ciba Gaiki Co., Ltd.) C, 1, Pigment Green 36 (Cyanine Green 5537-2Y, manufactured by Dainichiseika Chemical Co., Ltd.) C
91, Pigment Blue 15:3 (Sumikablin Tocyanin Blue GNI?-0, manufactured by Seikoku Kagaku Co., Ltd.) C, 1, Pigment Blue 60 (Chromophthal Blue^3R, manufactured by Ciba Geikie Co., Ltd.) C, 1, Pigment Violet 23 (Sumikablint Fast Violet RLN.

(Manufactured by Seiko Kagaku Co., Ltd.) If necessary, inorganic pigments such as red iron oxide, titanium oxide, and carbon black can also be used together with the above substances.

Examples of chromatic dyes include ab dyes, anthraquinone dyes, indigoid dyes, quinoneimine D dyes, and phthalocyanine dyes.

These chromatic colorants can be used alone or in combination of two or more, and the amount used is 3% in the toner.
The amount used is preferably ~20% by weight; if the amount used is less than 3% by weight, the chromaticity is low and it is difficult to obtain a color image with sufficient color, while if it exceeds 20% by weight In this case, the fixing performance tends to deteriorate during heat fixing of the toner image.

Other toner components include a charge control agent, a fluidity improver, an abrasive for the latent image support, and an agent for improving cleaning properties of the latent image support.

As the charge control agent, for example, IBN (Fettachwarz) having positive triboelectric charging properties as described in Japanese Patent Publication No. 41-2427.
IIBN ;c, 1. Floor 26150), alcohol (Nigrosin; C. 1. Na5041)
5), Sudan Chief Shubarut BB (Sudan
tiefschwarz BB; Solvent Black 3; C. 1. m26150), Brilliant Sprits TN
chwarz TN ; Falpen, Faprikeng,
(manufactured by Bahia), Zaponsc
hwarz
Ceresschwarz (R)G; Falpen,
Fabriken, manufactured by Baia), Chromogen schwarz ETOO (Chromogen schwarz ET)
OO; C. I.

Ik14645), Azo Oil Blank (R) (Az
Dyes such as o-Oi 1-Black (R); National (manufactured by Aniline Co., Ltd.), Spin Black TRII (manufactured by Hodogaya Chemical Co., Ltd.), Bontron S34 (manufactured by Orient Chemical Co., Ltd.), and pigments such as phthalocyanine blue may be mentioned. can. Further, oxidized carbon blanks and resins having positive or negative charge control groups can be considered as a type of charge control agent.

In order to improve the compatibility of these charge control agents with the binder resin, the above-mentioned substances may be salted with higher fatty acids and then incorporated into the binder resin, or the compatibility improver may be added together with the binder resin. It may be contained in the resin.

Examples of the fluidity improver and polishing agent for the latent image support include fine powders such as silica, amino-modified silica, titanium white, alumina, and cerium oxide. These substances may be contained in the binder resin together with other toner components, or may be added and mixed after obtaining the magnetic toner powder and adhered to the surface of the magnetic toner particles.

Examples of the cleaning property improving agent for the latent image support include fatty acid metal salts such as zinc stearate, fluorine resin powder, and the like.

As a method for manufacturing the magnetic toner of the present invention, conventionally known general toner manufacturing methods can be used. That is, for example, a binder resin, a powder made of 6n particles as described above, and other toner components to be added as necessary are premixed using a ball mill or the like, uniformly mixed and dispersed, and then heated rolls are used to mix and disperse the mixture. The magnetic toner has an average particle size of 5 to 301 fl, preferably 5 to 15 fl. obtain.

Note that the average particle size of the magnetic toner here refers to the average particle size of the magnetic toner.
The particle diameter is defined as the particle size when the cumulative weight is 50% when measured using a counter.

In addition, in some cases, it is desirable for the magnetic toner to have a spherical shape in order to obtain good fluidity. A preferred method is to spray the toner particles into hot air to instantaneously melt the surface of the toner particles and make the toner particles spherical by surface tension.

Other methods for producing magnetic toner include, for example, a method in which a monomer component of a binder resin is polymerized in the presence of magnetic powder as described above to form a polymer. This method is preferred because it is industrially stable and easy to manufacture.Specifically, the following method can be mentioned.

(1) A method in which ordinary bulk polymerization is carried out without a solvent at a temperature of 60 to 120° C. under a nitrogen stream.

(2) In water at a temperature of 60 to 120°C under a nitrogen stream, for example, gelatin, starch, polyvinyl alcohol, barium sulfate, calcium sulfate, barium carbonate, magnesium carbonate, calcium phosphate, talc/clay monosilicic acid, or metal oxides. A method in which suspension polymerization is carried out using a conventional method in the presence of powder, etc.

(3) Emulsification by a conventional method using an aqueous polymerization initiator in the presence of a surfactant such as sodium dodecylbenzenesulfonate, an alkyl sulfate type anionic emulsifier, or sodium dodecylsulfonate at a temperature of 40 to 90°C under a nitrogen stream. How to carry out polymerization.

(4) A suitable solvent (
A method in which solution polymerization is carried out by a conventional method in a state diluted with (for example, Hensen, xylene, ethanol, methyl ethyl ketone).

When producing a magnetic toner by the above method, it is preferable that the pH of the magnetic powder used is 6 or more, and the most preferable production method is the above method (2) using suspension polymerization. It's a method.

In addition, the magnetic particles are exposed on the surface of the magnetic toner particles.
When exposed with M, the triboelectric properties of the magnetic toner particles may be adversely affected by the triboelectrification properties of the magnetic particles. Alternatively, examples of higher fatty acids that can be used for this purpose and which are preferably coated with higher fatty acids include stearic acid, palmitic acid, and oleic acid. Coating can be easily carried out by immersing the non-containing particles in a solution dissolved in.

Further, in the magnetic toner of the present invention, its resistivity ρ (Ω
・+IJ) is preferably 1QIfΩ・1 or more. Here, resistivity ρ means that the sample is placed in a measurement cell with a cross-sectional area of 1c+J (Fc+J) at a thickness of 0.03 to 0.08 hc.
+a), a load of 1 kg is applied from the top surface, and the current value (i ampere) when the DC applied voltage (V volts) is varied is measured and calculated using the following formula.

Xh [Example] Examples of the present invention will be described below, but the present invention is not limited to these examples.
represents the department.

Example 1 Cross-linked polyester resin 50 parts Powder consisting of magnetic particles 50 parts (proportion of metallic iron in magnetic particles = 81% by weight, other composition components: magnetite) C,1, Pigment Red 5 9 parts (permanent carmine FB, (manufactured by Hoechst Japan) Mold release agent 3 parts Hoechstwax OPJ (manufactured by Hoechst Japan) The materials of the above formulation were mixed and dispersed in a ball mill, melted, kneaded, pulverized, and classified to form a red magnetic powder with an average particle size of 12n. A toner powder was obtained, and hydrophobic silica fine powder rR-972J (manufactured by Nippon Aerosil Co., Ltd.) was added and mixed in a proportion of 0.4% by weight to produce a red color magnetic toner.This magnetic The toner is referred to as "toner l".

Using this toner l, a modified electrophotographic copying machine r U-Bix 1200J (manufactured by Konishiroku Photo Industry Co., Ltd.) was prepared using a selenium photoconductor as a photoconductor and the magnetism of the charging electric scraper and transfer bridge was changed to positive magnetism. When we conducted a live-action test,
A red image without fog was obtained.

Next, toner 1 was examined for its fixing properties and offset generation temperature. The results are shown in Table 1 below.

Regarding fixing properties, the electrophotographic copying machine rU-Bix160
Using a fixing device for 0J (manufactured by Konishiroku Photo Industry Co., Ltd.), the toner image was fixed with the upper roller temperature set at 190°C, and the resulting fixed image was transferred to the rJK Wiper 150-
II re, fi by SJ (manufactured by Jujo Kimberly Co., Ltd.)
It was investigated whether stains caused by the JK'7 (par 150-3) +- had occurred. In Table 1, rOJ indicates that there is almost no toner staining and the fixing is sufficient;
” indicates that toner stains have occurred and fixing is poor.

Regarding the offset/7t generation temperature, please refer to the electrophotographic copying machine r.
U-Bix 1600J (manufactured by Konishiroku Photo Industry Co., Ltd.)
The toner image was fixed using a fixing device, and the set temperature of the upper roller was gradually increased at each temperature, and the temperature at which the offset phenomenon occurred was determined.

Example 2 Crosslinked polyester resin 50 parts Powder consisting of magnetic particles 50 parts (proportion of metallic iron in magnetic particles: 65% by weight, other composition components: magnetite) C,1, Pigment Blue 15:3 9 parts (
Sumikablin Tocyanine Blue GNR-0, manufactured by Sumima Kagaku Co., Ltd.) Nigrosine Base EX J 2 parts (manufactured by Orient Chemical Co., Ltd.) Mold release agent 3 parts Hoechst Wax SJ (manufactured by Hoechst Japan Co., Ltd.) The materials of the above formulation were used in Example 1 A dark blue magnetic toner powder was obtained by processing in the same manner as in Example 1, and hydrophobic silica powder was added and mixed in the same manner as in Example 1, thereby producing a dark blue color magnetic toner. This magnetic toner is referred to as "toner 2".

When a photocopying test was conducted using this toner 2 in the same manner as in Example 1, the resulting photocopied image was a dark blue image with no fog.

Next, in the same manner as in Example 1, this toner 2 was examined for fixability and offset generation temperature. The results will be explained in the first section below.
Shown in the table.

Example 3 Cross-linked polyester resin 55 parts Powder consisting of magnetic particles 45 parts (proportion of metallic iron in fii particles = 93% by weight, other composition components:
Magnetite) C11, Pigment Blue 15:3 2 parts (
Sumikablin Tocyanine Blue GNR-0, manufactured by Sumima Kagaku Co., Ltd.) C,1, Pigment Yellow 17 7 parts (Fast Yellow GBFN, manufactured by Sumima Kagaku Co., Ltd.) Mold release agent
3 parts: Hoechstowanox Cl (manufactured by Hoechst Javan Co., Ltd.) Low molecular weight polypropylene 2 parts: Viscole 660P J (manufactured by Sanyo Chemical Co., Ltd.) The materials of the above formulation were treated in the same manner as in Example 1 to obtain a green magnetic toner powder. A hydrophobic silica fine powder was added and mixed to the toner powder in the same manner as in Example 1 to produce a green color magnetic toner.This magnetic toner is referred to as "Toner 3".

When a photocopying test was conducted using this toner 3 in the same manner as in Example 1, the resulting photocopied image was a green image without fogging.

Next, the fixability and offset occurrence temperature of this toner 3 were examined in the same manner as in Example 1. The results will be explained in the first section below.
Shown in the table.

Example 4 Instead of the mold release agent in Example 1, a mold release agent consisting of 3 parts of "Carnauba wax" (manufactured by Noda Wax Co., Ltd.) and 3 parts of "Hoechst wax CJ (manufactured by Hoechst Japan Co., Ltd.) was used. A magnetic toner was produced in the same manner as in Example 1, except for using the following materials.This magnetic toner is referred to as "Toner 4."

When a photocopying test was conducted using this toner 4 in the same manner as in Example 1, the resulting photocopied image was a red image with no fog.

Next, the fixability and offset occurrence temperature of this toner 4 were examined in the same manner as in Example 1. The results will be explained in the first section below.
Shown in the table.

Example 5 Styrene-acrylic copolymer 50 parts (styrene: n-butyl acrylate-75: 25, weight average molecular weight Mw = 12 X 10') Powder consisting of magnetic particles 50 parts (ratio of metallic iron in magnetic particles 281 Weight %, other composition components: magnetite) C,! , Pigment Red 5 9 parts (permanent carmine FB, manufactured by Hoechst Japan Co., Ltd.) Nigrosine Base EX J 2 parts (manufactured by Orient Chemical Co., Ltd.) Mold release agent 3 parts ``Carnauba wax'' (manufactured by Noda Wax Co., Ltd.) Low molecular weight polypropylene 3 Department [Viscoal 660PJ (
(Manufactured by Sanyo Kasei Co., Ltd.) The above-prescribed materials were treated in the same manner as in Example 1 to obtain red magnetic toner powder, and hydrophobic silica fine powder was added and mixed to this toner powder in the same manner as in Example 1.
A red color magnetic toner was thus produced.

This magnetic toner is referred to as "toner 5".

Using this toner 5, an electrophotographic copying machine rU-Bix
1200J (manufactured by Konishiroku Photo Industry Co., Ltd.), a photocopy test was conducted, and the resulting copied image was a red image with no fog.

Next, the fixability and offset occurrence temperature of this toner 5 were examined in the same manner as in Example 1. The results will be explained in the first section below.
Shown in the table.

Comparative Example 1 A magnetic toner was produced in the same manner as in Example 5 except that the release agent was omitted. This magnetic toner was used as “comparison toner”
”.

Regarding this comparative toner I, the fixability and offset occurrence temperature were investigated in the same manner as in Example 1. The results are shown in Table 1 below.

Table 1 As can be understood from the results in Table 1, toners 1 to 5 according to the present invention can all form images with sufficient fixation, and have a high offset generation temperature and offset This phenomenon is unlikely to occur. On the other hand, Comparative Toner 1 does not contain a release agent, so the resulting image has poor fixing properties, and moreover, the offset generation temperature is low and the offset phenomenon is likely to occur.

(Effects of the Invention) According to the present invention, since metallic iron is present in the particles constituting the magnetic powder in a proportion of 50 to 100% by weight, the obtained magnetic toner has a large magnetization ability and a good property. It is possible to obtain magnetic properties and therefore to form fog-free images, and because it contains a specific mold release agent and these mold release agents have good compatibility with the binder resin.
Excellent non-offset properties can be imparted to the toner, preventing the occurrence of offset phenomena, and the smoothness of the toner particle surface has been improved, making it highly resistant to external mechanical forces such as rubbing in fixed images. Therefore, the storage stability of the fixed image is improved, and as a result, it becomes possible to form an image with good fixability without the occurrence of an offset phenomenon. Since the magnetic powder itself is colorless or exhibits a hue close to gray, when a chromatic colorant is contained, the color corresponding to the content of the chromatic colorant will fully appear, and the As a result, it is possible to obtain a color stone-based toner that can form color images of various colors.

Claims (1)

[Claims] 1) 50 to 100% by weight of metallic iron in the binder resin
1. A magnetic toner comprising: magnetic powder consisting of particles present in a ratio of 1 to 1; and a release agent selected from the group shown in (a) to (d) below. (a) Fatty acid ester wax (b) Partially saponified fatty acid ester wax (c) Fatty acid amide wax (d) Higher fatty acid wax 2) A patent characterized in that the binder resin further contains a chromatic colorant The magnetic toner according to claim 1.