JP2003005429A - Color toner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a color toner which can maintain a sharp image for a long time as it is immediately after copying and which does not contaminate a photoreceptor, a sleeve or the like. SOLUTION: In the color toner containing at least a binder resin and a coloring agent, the acid value of the toner ranges from 5 to 45 mgKOH/g. The molecular weight distribution of the resin component of the toner shows 1,000 to 100,000 number average molecular weight (Mn) by gel permeation chromatography(GPC). The coloring agent contains nitrogen, while the binder resin consists of a copolymer containing nitrogen. When the toner is extracted with tetrahydrofuran(THF) by Soxhlet extraction, the solution containing the extracted soluble content has <=20% transmittance at 350 nm wavelength by UV-visible spectroscopy.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color toner used in an image forming method such as electrophotography and electrostatic recording or a toner jet recording method.

[0002]

2. Description of the Related Art In recent years, in copying machines and the like using electrophotography, the development to color has been rapidly progressing, and color developers have come to be widely used.

Colorants such as dyes and pigments are generally used to color the developers. Today, dyes and pigments known in the art include azo yellow pigments, phthalocyanine blue pigments, anthraquinone color pigments,
Examples include quinacridone yellow pigments and perylene red pigments.

Furthermore, as a binder resin for color,
Especially when used in a full-color copying machine, the following conditions are required. That is, in a full-color machine, it is necessary to carry out development a plurality of times and to superimpose several layers of different colors on the same support, so the fixed developer diffusely reflects light and reproduces colors. Therefore, it is necessary for the shape of the particles to be in a state of almost complete melting so that the particles cannot be discriminated.

The color binder resins used today are polyester resins, epoxy resins, styrene.
Styrene-based copolymers such as acrylic copolymers, and blends or graft resins in which a plurality of them are combined are known.

[0006]

However, the developer containing the above dye / pigment and resin has some problems. One of them is that the formed color image cannot permanently maintain good image quality immediately after copying. That is, even a clear image immediately after copying causes deterioration in image quality such as a decrease in image density and a loss of color balance when left in a bright place. It is considered that this is because the dye / pigment absorbs natural light or ultraviolet rays contained in lighting to cause a photochemical reaction, resulting in deterioration.

In order to achieve such a requirement, a dye and / or a pigment, an ultraviolet absorber and / or a binder resin are contained in the binder resin.
Alternatively, a method of incorporating an antioxidant (Japanese Patent Application Laid-Open No. 01-1 / 1991)
No. 72924), but ultraviolet absorbers and antioxidants released during repeated copying adhere to the developing device and the photoconductor, and in the case of a two-component developer, strongly adhere to the carrier and adversely affect development. Exert.

Further, a method using a binder resin containing a benzophenone type monomer (Japanese Patent Laid-Open No. 06-019187).
In this case, the transparency of the OHP was not sufficient because the dispersion of the colorant in the binder resin was not so good, and the weather resistance of the toner was not improved so much.

An object of the present invention is to provide a color toner having a novel structure that solves the above problems.

[0010]

As a result of various studies, the present inventors have found that a good electrostatic image developer can be obtained by using a developer having the following constitution.

That is, in a color toner containing at least a binder resin and a colorant, the toner has an acid value of 5
~ 45 mgKOH / g, and the resin component of the toner is
In the molecular weight distribution by gel permeation chromatography (GPC), the number average molecular weight (Mn) is 1,
000 to 100,000, the colorant contains nitrogen, the binder resin is a nitrogen-containing copolymer, and the toner contains soluble components extracted by Soxhlet extraction with tetrahydrofuran (THF). The light transmittance of the solution by UV-visible spectroscopy is 2 at a wavelength of 350 nm.
Good performance was obtained when a color toner characterized by being 0% or less was used.

First of all, the effective action of the binder resin used in the present toner is high UV resistance. An image obtained by developing and fixing a toner using the binder resin can suppress the influence of ultraviolet rays contained in natural light or lighting even if left in a bright place for a long time. As a result, the fixed image is protected from ultraviolet rays, and a clear image immediately after copying can be maintained for a long time.

Further, in the present invention, since the UV resistant monomer is polymerized, there is no contamination on the photoreceptor, sleeve, etc., which is a problem in the conventional developer containing the UV resistant agent.

Further, in the present invention, since the colorant is very well dispersed in the binder resin, excellent OHP transparency can be exhibited. It is considered that this is because both the binder resin and the colorant contain nitrogen, so that the mutual affinity is improved and an excellent dispersion effect is exhibited.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION In the toner of the present invention, it is very preferable that the binder resin and the colorant contain nitrogen in terms of dispersion of the colorant. The reason for this is not clear, but probably because both the colorant and the binder resin contain nitrogen, the mutual affinity improves and the colorant is finely dispersed in the binder resin. Is.

In the present invention, the molecular weight distribution by GPC in the resin component of the toner is as follows, gel permeation chromatography (GPC) using a THF-soluble component obtained by dissolving the toner in a THF solvent.
Means the molecular weight distribution measured by.

That is, the toner is put in THF, left to stand for several hours, then shaken sufficiently and mixed well with THF (until the coalescence of the sample disappears), and then allowed to stand for 12 hours or more.
At this time, the leaving time in THF should be 24 hours or more. After that, a sample processing filter (pore size 0.45-0.5 μm, for example, Mysholydisk H
-25-5 manufactured by Tosoh Co., Ltd., available from Ekikuro Disc 25CR Gelman Science Japan Co., Ltd.) are used as GPC samples. The sample concentration is
The resin component is adjusted to 0.5 to 5 mg / ml.

The resin component of the toner of the present invention has a number average molecular weight (Mn) of 1,000 to 100 in the molecular weight distribution by GPC.
The fixability is preferably 100,000, and preferably 2000 to 70,000, and the crushability is good for a pulverized toner having a pulverization step during toner production.

The acid value of the toner is 5 to 45 mgKOH.
/ G is good, more preferably 10-40 mg
KOH / g is good. If it is less than 5 mgKOH / g, it is likely that the pigment and the organometallic compound are difficult to disperse, and thus charging failure, image unevenness, and fog are likely to occur. When it exceeds 45 mgKOH / g, the hygroscopicity of the binder resin is enhanced, so that the charge relaxation of the toner becomes strong, and the toner scattering and the transferability deteriorate.

Further, the light transmittance of the solution containing the soluble matter extracted by Soxhlet extraction of the toner of the present invention with tetrahydrofuran (THF) by UV-visible spectroscopy is:
The transmittance at a wavelength of 350 nm is preferably 20% or less. If the transmittance at a wavelength of 350 nm is higher than 20%, the resistance to ultraviolet rays becomes weak, and especially when a coloring agent having poor weather resistance is used, leaving it in a bright place for a long time causes a decrease in image density and However, image quality deterioration such as a loss of color balance occurs.

The binder resin used in the present invention is preferably one obtained by copolymerizing a UV resistant monomer. Among the UV-resistant monomers used in the present invention, examples of nitrogen-containing monomers include hindered amines, benzotriazoles, oxalic anilides, triazines, cyanoacrylates, and the like, and benzoic acid esters as nitrogen-free monomers. , Phenyl salicylates, benzophenones, hindered phenols and the like.

Specific examples of the nitrogen-containing monomer are hindered amines, which are piperidine derivatives having a sterically hindering group. For example, 4-acetoxy-2,2,6,6.
-Tetramethylpiperidine, 4-stearoyloxy-
2,2,6,6-tetramethylpiperidine, 4-acryloyloxy-2,2,6,6-tetramethylpiperidine, 4-methoxy-2,2,6,6-tetramethylpiperidine, 4-benzoyloxy- 2,2,6,6-tetramethylpiperidine, 4-cyclohexyloxy-2,
2,6,6-Tetramethylpiperidine, 4-phenoxy-2,2,6,6-tetramethylpiperidine, 4-benzyloxy-2,2,6,6-tetramethylpiperidine, 4- (phenylcarbamoyloxy) -2,2
6,6-Tetramethylpiperidine, bis (2,2,6,
6-tetramethyl-4-piperidyl) oxalate, bis (2,2,6,6-tetramethyl-4-piperidyl)
Malonate, bis (2,2,6,6-tetramethyl-4
-Piperidyl) adipate, bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis (1,
2,2,6,6-pentamethyl-4-piperidyl) sebacate, bis (2,2,6,6-tetramethyl-4-piperidyl) terephthalate, 1,2-bis (2,2,2
6,6-Tetramethyl-4-piperidyloxy) ethane, bis (2,2,6,6-tetramethyl-4-piperidyl) hexamethylene-1,6-zircabamate, bis (1-methyl-2,2,2) 6,6-tetramethyl-4-piperidyl) adipate, tris (2,2,6,6-tetramethyl-4-piperidyl) benzene-1,3,5-tricarboxylate and the like. Also, a high-molecular weight piperidine derivative polycondensate, for example, dimethyl-1-succinate.
(2-hydroxyethyl) -4-hydroxy-2,2
6,6-Tetramethylpiperidine polycondensate and the like are also effective.

As the benzotriazoles, 2-
(2′-hydroxy-5′-methyl-phenyl) benzotriazole, 2- (2′-hydroxy-3 ′, 5′-
Di-t-butyl-phenyl) benzotriazole, 2-
(3,5-di-t-amyl-2-hydroxyphenyl)
Benzotriazole, 2- (2'-hydroxy-3 ',
5'-di-isoamyl-phenyl) benzotriazole, 2- [2-hydroxy-3,5-bis- (α, α-
Dimethylbenzyl) phenyl] benzotriazole, 2
Examples thereof include-(2'-hydroxy-4'-octoxyphenyl) benzotriazole and 2- [2'hydroxy-5 '-(acryloyloxy) phenyl] benzotriazole.

Oxalic acid anilides include N- (2-ethyl-phenyl) -N '-(2-ethoxy-5-t-butylphenyl) oxalic acid diamide, N- (2-ethyl-phenyl) -N'. Examples include-(2-ethoxy-phenyl) oxalic acid diamide.

Cyanoacrylates include 2-ethylhexyl-2-cyano-3,3-diphenyl acrylate,
Examples thereof include ethyl-2-cyano-3,3-diphenyl acrylate.

When a UV-resistant monomer containing no nitrogen is used in the binder resin of the present invention, it is preferable to use another polymerizable monomer containing nitrogen (such as acrylonitrile).

It is preferable to blend at least one kind or two or more kinds of these UV resistant monomers, and when two kinds are blended, it is particularly preferable to use a combination of a benzotriazole type substance and a hindered amine type substance.

The polymerizable monomer to be copolymerized with the UV resistant monomer is, for example, styrene; o-methylstyrene, m-methylstyrene, p-methylstyrene, α-
Methylstyrene, p-phenylstyrene, p-ethylstyrene, 2,4-dimethylstyrene, pn-butylstyrene, p-tert-butylstyrene, pn-hexylstyrene, pn-octylstyrene, p- n-nonylstyrene, pn-decylstyrene, pn-dodecylstyrene, p-methoxystyrene, p-chlorostyrene, 3,4-dichlorostyrene, m-nitrostyrene, o-nitrostyrene, p-nitro Styrene such as styrene and its derivatives; Styrene unsaturated monoolefins such as ethylene, propylene, butylene, isobutylene; Unsaturated polyenes such as butadiene and isoprene;
Vinyl halides such as vinyl chloride, vinylidene chloride, vinyl bromide and vinyl fluoride; vinyl esters such as vinyl acetate, vinyl propionate and vinyl benzoate.
Methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, phenyl methacrylate, dimethylamino methacrylate. Α-Methylene aliphatic monocarboxylic acid esters such as ethyl and diethylaminoethyl methacrylate; methyl acrylate, ethyl acrylate, propyl acrylate, n-butyl acrylate, isobutyl acrylate, n-octyl acrylate, dodecyl acrylate , 2-ethylhexyl acrylate, stearyl acrylate,
Acrylic esters such as 2-chloroethyl acrylate 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; N -Vinylpyrrole, N-vinylcarbazole,
N such as N-vinylindole and N-vinylpyrrolidone
-Vinyl compounds; vinyl naphthalenes; acrylic acid or methacrylic acid derivatives such as acrylonitrile, methacrylonitrile and acrylamide.

Further, the binder resin of the present invention may be made into a binder resin by mixing the copolymer containing the UV resistant monomer with another resin.

The resin to be mixed is, for example, polystyrene, styrene-butadiene copolymer, styrene-based copolymer such as styrene-acrylic copolymer, polyethylene, ethylene-vinyl acetate copolymer, ethylene-vinyl alcohol copolymer. Examples thereof include ethylene-based copolymers such as coalesce, phenol-based resins, epoxy-based resins, acrylic phthalate resins, polyamide resins, polyester resins, maleic acid-based resins, and hybrid resins of polyester and styrene / acryl. In addition, the manufacturing method and the like of each resin are not particularly limited.

In the production of the toner of the present invention, the constituent materials are well kneaded by a heat kneader such as a heat roll, a kneader, an extruder, etc., and then mechanical pulverization / classification is used, or the binder resin solution is colored. A method of obtaining a toner by dispersing materials such as an agent and then spray-drying, or a method of obtaining a toner by mixing a predetermined material with a monomer that constitutes a binder resin and then performing emulsion suspension polymerization. Each method can be applied.

The amount of the UV resistant monomer used is preferably 0.01 to 20 parts by mass with respect to 100 parts by mass of the binder resin.

The coloring agent used in the present invention may be any one as long as it is a nitrogen-containing coloring agent.

For example, as the dye, C.I. I. Direct Red 1, C.I. I. Direct Red 4, C.I. I. Acid Red 1, C.I. I. Basic Red 1, C.I. I.
Mordant Red 30, C.I. I. Direct Blue 1,
C. I. Direct Blue 2, C.I. I. Acid Blue 9, C.I. I. Acid Blue 15, C.I. I. Basic Blue 3, C.I. I. Basic Blue 5, C.I. I. Mordant Blue 7, C.I. I. Direct Green 6, C.I.
I. Basic Green 4, C.I. I. Examples include Basic Green 6 and Solvent Yellow 162.

As the pigment, naphthol yellow S, Hansa yellow G, permanent yellow NCG, tartrazine lake, permanent orange GTR, pyrazolone orange, benzidine orange G, permanent red 4R, watching red calcium salt, brilliant carmine 3B, manganese purple. , Fast Violet B, Methyl Violet Lake, Alkali Blue Lake, Victoria Blue Lake, Phthalocyanine Blue,
First Sky Blue, Indren Sren Blue BC,
Pigment Green B, Malachite Green Lake, and the like.

When used as a full-color image forming toner, magenta coloring pigments include C.I.
I. Pigment Red 1, 2, 3, 4, 5, 6, 7,
8, 9, 10, 11, 12, 13, 14, 15, 16,
17,18,19,21,22,23,30,31,3
2,37,38,39,40,41,48,49,5
0,51,52,53,54,55,57,58,6
0,63,64,68,81,83,87,88,8
9, 90, 112, 114, 122, 123, 163
202, 206, 207, 209, 238, C.I. I. Pigment violet 19, C.I. I. Bat red 1
0, 13, 15, 23, 29, 35 and the like.

Although such a pigment may be used alone,
From the viewpoint of the image quality of a full-color image, it is more preferable to use a dye and a pigment together to improve the sharpness. Examples of magenta dyes include C.I. I. Solvent Red 1,3,8,2
3,24,25,27,30,49,81,82,8
3,84,100,109,121, C.I. I. Disperse Red 9, C.I. I. Solvent Violet 8,1
3, 14, 21, C.I. I. Disperse Violet 1
Oil-soluble dyes such as C.I. I. Basic red 1, 2,
9, 12, 13, 14, 15, 17, 18, 22, 2
3,24,27,29,32,34,35,36,3
7, 38, 39, 40, C.I. I. Basic Violet 1,3,7,10,14,15,21,25,26,
And basic dyes such as 27 and 28.

As the color pigment for cyan, C.I. I. Pigment Blue 2, 3, 15, 16, 17; C.I. I. Acid Blue 6; C.I. I. Acid Blue 45 or a copper phthalocyanine pigment having 1 to 5 phthalimidomethyl groups substituted on the phthalocyanine skeleton.

As the color pigment for yellow, C.I. I. Pigment Yellow 1, 2, 3, 4, 5, 6, 7, 10,
11, 12, 13, 14, 15, 16, 17, 23, 6
5, 73, 74, 83, 93, 97, 155, 180,
C. I. Butt Yellow 1, 3, 20 and the like.

As the black colorant used in the present invention, carbon black, a magnetic substance, and a color tone adjusted to black using the above-mentioned yellow / magenta / cyan colorant can be used.

The amount of the colorant used is preferably 0.1 to 15 parts by mass, more preferably 0.5 to 12 parts by mass, and most preferably 3 to 10 parts by mass with respect to 100 parts by mass of the binder resin. .

Further, a charge control agent may be blended in order to stabilize the charging characteristics of the color toner of the present invention. that time,
A colorless or light-colored charge control agent that does not affect the color tone of the colored particles or the colorant is preferable. As the negative charge control agent at that time, for example, a metal compound of alkyl-substituted salicylic acid (for example, a chromium compound of di-tert-butylsalicylic acid,
Examples thereof include organic compounds such as zinc compounds or aluminum compounds). When the negative charge control agent is blended, it is added in an amount of 0.1 to 10 parts by weight, preferably 0.5 to 8 parts by weight, based on 100 parts by weight of the binder resin.

As the positive charge control agent, a quaternary ammonium salt or a polymer having a quaternary ammonium salt in its side chain is known. The compounding amount is the same as that of the negative charge control agent.

Further, low molecular weight polyethylene, low molecular weight polypropylene, microcrystalline wax, carnauba wax, sazol wax, paraffin wax, ester wax, alcohol modified wax, urethane modified wax for the purpose of improving releasability during heat roll fixing. 0.5 to about waxy substances such as
Adding about 10% by mass is also one of the preferred embodiments of the present invention.

As the polyolefin monomer used in the present invention, ethylene, propylene, butene-1, pentene-1, hexene-1, heptene-1, octene-
1, straight chain α-olefins such as 1, nonene-1, and decene-1, branched α-olefins having a branched portion at the terminal, and olefins having different unsaturated group positions, and the like. Homopolymerized olefins or copolymerized olefins thereof are exemplified.

Further, in the color toner of the present invention, a fluidity improver may be added for the purpose of improving its fluidity.

The flow improver used in the present invention includes:
As long as the fluidity can be increased by adding it to the colorant-containing resin particles before and after the addition, any material can be used.

For example, fluorine-based resin powder, that is, fine powder of vinylidene fluoride, fine powder of polytetrafluoroethylene, or the like; or fatty acid metal salt, that is, zinc stearate,
Calcium stearate, lead stearate, etc .; or metal oxides, ie zinc oxide powder, etc .; or finely powdered silica, that is, wet process silica, dry process silica, silane coupling agents, titanium coupling agents, silicone oils, etc. Examples include treated silica that has been surface treated.

A preferable flow improver is a fine powder produced by vapor phase oxidation of a silicon halogen compound, which is so-called dry process silica or fumed silica, which is produced by a conventionally known technique. Is. For example, the thermal decomposition oxidation reaction of silicon tetrachloride gas in oxyhydrogen flame is utilized, and the basic reaction formula is as follows. SiCl ₄ + 2H ₂ + O ₂ → SiO ₂ + 4HCl

In this manufacturing process, it is also possible to obtain a fine composite powder of silica and another metal oxide by using another metal halogen compound such as aluminum chloride or titanium chloride together with the silicon halogen compound. Also includes.

The particle size is 0.0 as the average primary particle size.
It is desirable to be in the range of 01 to 2 μm, and it is particularly preferable to use fine silica powder in the range of 0.002 to 0.2 μm.

Further, if necessary, a fatty acid metal salt such as zinc stearate, stearic acid and aluminum, a fluorine-containing polymer such as polytetrafluoroethylene, polyvinylidene fluoride and tetrafluoroethylene-vinylidene fluoride copolymer. Fine powder or tin oxide,
A conductivity-imparting agent such as zinc oxide or titanium oxide may be added.

When the color toner of the present invention is used as a two-component developer, the carrier used during the development also plays an important role so that the effect can be sufficiently exhibited.

Examples of the carrier used in the present invention include surface-oxidized or non-oxidized iron, nickel, copper, zinc,
Metals such as cobalt, manganese, chromium, lithium, rare earths, their alloys or oxides and ferrites can be used. In addition, there is no particular limitation on the manufacturing method.

The system in which the surface of the carrier is coated with a resin or the like is particularly preferable in the J / B developing method. As the method, any conventionally known method such as a method of dissolving or suspending a coating material such as a resin in a solvent and applying the coating material and attaching it to a carrier, or a method of simply mixing with a powder can be applied.

The substance adhered to the surface of the carrier varies depending on the toner material, but for example, polytetrafluoroethylene, monochlorotrifluoroethylene polymer, polyvinylidene fluoride, silicone resin, polyester resin,
Metallic complex of tert-butyl salicylic acid, styrene resin, acrylic resin, polyamide, polyvinyl butyral, nigrosine, amino acrylate resin, basic dye and its lake, silica fine powder, alumina fine powder, etc. are used alone or in combination. Is suitable, but is not necessarily limited to this.

The amount of the above-mentioned compound to be treated may be appropriately determined so that the carrier satisfies the above conditions, but generally, the total amount is 0.1 to 30% by mass (preferably 0.5 to 20) based on the carrier of the present invention. Mass%) is desirable.

The average particle size of these carriers is 10 to 100.
It is preferable to have a thickness of μm, preferably 20 to 70 μm.

In a particularly preferred embodiment, Cu-Zn-
It is a ternary ferrite of Fe, and its surface is a combination of resins such as fluorine resin and styrene resin, for example, polyvinylidene fluoride and styrene-methyl methacrylate resin; polytetrafluoroethylene and styrene-methyl methacrylate resin, A mixture of a fluorine-based copolymer and a styrene-based copolymer; etc. in a ratio of 90:10 to 20:80, preferably 70:30 to 30:70, and 0.01 to 5% by mass, preferably 0.1-1% by mass
An example of the coated ferrite carrier is a coated ferrite carrier having the above-mentioned average particle diameter of 70 mass% or more of carrier particles of 250 mesh pass / 400 mesh on. Examples of the fluorine-based copolymer include vinylidene fluoride-tetrafluoroethylene copolymer (10: 90-9
0:10), and the styrene-based copolymer is styrene-2-ethylhexyl acrylate (20: 80-
80:20), styrene-2-ethylhexyne acrylate-methyl methacrylate (20-60: 5-30: 10).
˜50) are illustrated.

The above-mentioned coated ferrite carrier has a sharp particle size distribution, and it is possible to obtain a preferable triboelectrification property for the toner of the present invention and to improve electrophotographic characteristics.

When a two-component developer is prepared by mixing with the toner of the present invention, the mixing ratio is usually 2 to 15% by mass, preferably 4 to 13% by mass as the toner concentration in the developer. Results are obtained. If the toner density is less than 2% by mass, the image density will be too low for practical use.
If the content exceeds 100% by mass, fog and scattering in the machine will increase, and the useful life of the developer will be shortened.

The method for measuring the physical properties of the toner of the present invention is as follows.

(1) Method for measuring acid value 2 to 10 g of a sample is weighed in a 200 to 300 ml Erlenmeyer flask, and about 50 ml of a mixed solvent of methanol: toluene = 30: 70 is added to dissolve the resin. If the solubility seems to be poor, a small amount of acetone may be added. Using a mixed indicator of 0.1% bromthymol blue and phenol red, titration was performed with a previously standardized N / 10 potassium hydroxide-alcohol solution, and the acid value was calculated from the consumption amount of the alcohol potassium solution by the following calculation formula. . Acid value = KOH (ml number) × f × 56.1 / sample mass (where f is a factor of N / 10 KOH)

When the toner contains magnetic powder, the residue obtained by eluting the magnetic material with an acid is measured as a sample.

(2) Molecular weight distribution by GPC measurement The molecular weight of the chromatogram by gel permeation chromatography (GPC) is measured under the following conditions.

The column was stabilized in a heat chamber at 40 ° C., and THF was used as a solvent for the column at this temperature.
At a flow rate of 1 ml per minute to obtain a sample concentration of 0.05-
About 50% of the THF sample solution of the resin adjusted to 0.6 mass%
Inject ~ 200 μl and measure. In measuring the molecular weight of a sample, the molecular weight distribution of the sample is calculated from the relationship between the logarithmic value and the number of counts (retention time) of a calibration curve prepared from several kinds of monodisperse polystyrene standard samples. The standard polystyrene sample for preparing the calibration curve is, for example, manufactured by Tosoh Corporation or Pressure Chemical.
al Co. Made of 6 × 10 ² , 2.1 × 10 ³ ,
4 × 10 ³ , 1.75 × 10 ⁴ , 5.1 × 10 ⁴ , 1.1
× 10 ⁵ , 3.9 × 10 ⁵ , 8.6 × 10 ⁵ , 2 × 10 ⁶ ,
It is suitable to use a standard polystyrene sample of 4.48 × 10 ⁶ and at least about 10 points. An RI (refractive index) detector is used as the detector.

As the column, a plurality of commercially available polystyrene gel columns may be combined in order to accurately measure the molecular weight region of 10 ³ to 2 × 10 ⁶ , for example, shodex GPC KF-801 manufactured by Showa Denko KK 80
2, 803, 804, 805, 806, 807 combinations and Waters μ-styragel 50
A combination of 0, 10 ³ , 10 ⁴ and 10 ⁵ can be mentioned.

(3) Preparation of Solution Containing THF-Soluble Content 2 g of the toner is weighed, put in a cylindrical filter paper (for example, No. 86R size 28 × 100 mm manufactured by Toyo Filter Paper Co., Ltd.), and put on a Soxhlet extractor. Extract for 6 hours with 200 ml of THF as solvent. At this time, extraction is performed at a reflux rate such that the THF extraction cycle is once every about 4 to 5 minutes. The obtained extract is directly subjected to UV-visible spectroscopy without being concentrated.

(4) UV-Visible Spectroscopy Measurement was carried out with a Shimadzu self-recording spectrophotometer UV2200 (manufactured by Shimadzu Corporation). An optical cell having an optical path length of 1 mm is prepared, and the above extraction liquid is filled therein. The optical cell does not absorb or scatter in the ultraviolet and visible light range, and for example, a quartz cell or the like is used. A UV-Visible spectrophotometer is used to measure the transmittance of light passing through this optical cell. At this time, the same optical cell filled with THF is used as a control to remove the background.

[0070]

EXAMPLES Hereinafter, specific examples of the present invention will be described, but the present invention is not limited to these examples.

The physical properties of the binder resin used in this example are shown in Table 1.

<Example 1> Magenta toner 1 was prepared by the following method. Binder resin (1) 100 parts by mass Paraffin wax 2 parts by mass C.I. I. Pigment Red 57 5 parts by mass / di-tert-butylsalicylic acid aluminum complex 4 parts by mass are sufficiently premixed by a Henschel mixer,
The mixture was melt-kneaded with a twin-screw extruder, cooled, and then coarsely pulverized to a particle size of about 1 to 2 mm using a hammer mill. Then, it was pulverized by an air jet pulverizer. Further, the obtained finely pulverized product was classified by a multi-division classifier to obtain magenta resin particles having a weight average particle diameter of 8.0 μm.

To 100 parts by mass of the magenta resin particles, 1.0 part by mass of hydrophobic titanium oxide (BET110 m ^{2 /} g) treated with n-C ₄ H ₉ Si (OCH ₃ ) ₃ was added, and magenta toner was added. It was set to 1. Magenta Toner 1
And magnetic ferrite carrier particles surface-coated with a silicone resin (average particle size 50 μm) were mixed so as to have a toner concentration of 6% by mass to obtain a two-component magenta developer 1. The toner measurement results are shown in Table 2.

Using this magenta developer 1, continuous copying 1 was performed with a color copying machine CLC-800 (manufactured by Canon Inc.).
Durability test was performed on 10,000 sheets. The results are shown in Table 3.
As shown in Table 3, toner scattering, fog, and reduction in image density did not occur even after 10,000 sheets of running, and good results that were the same as the initial results were obtained. The image area ratio at this time was 25%, and the amount of applied toner per unit area was set to 0.7 mg / cm ² .

The toner scattering was evaluated according to the following criteria by observing the condition inside the copying machine after 10,000 sheets of durability test. A: No toner scattering occurs. B: A slight scattering is seen around the developing device. C: Contamination is found around the developing device. D: The area around the developing device is severely contaminated by the scattered toner.

The fog was evaluated by measuring the whiteness of the white background with a reflectometer (manufactured by Tokyo Denshoku Co., Ltd.) and calculating the fog density (%) from the difference between the whiteness and the whiteness of the transfer paper. The evaluation criteria are as follows. A: Very good (less than 1.0%) B: Good (1.0% to 2.0%) C: Normal (2.0% to 3.0%) D: Bad (3.0% or more)

The OHP transparency is measured by measuring the area per unit area.
Toner amount is 0.7 mg / cm ²Set to Shimadzu
Using spectrophotometer UV2200 (manufactured by Shimadzu Corporation)
It was The transmittance of the OHP film alone is 100%, For magenta toner: 650 nm For cyan toner: 500 nm For yellow toner: 600 nm The transmittance at the maximum absorption wavelength at is measured. A: 85% or more B: 75-85% C: 65-75% D: less than 65%

The image density was averaged five times using a Macbeth densitometer manufactured by Macbeth.

The color tone of the toner was quantitatively measured based on the definition of the color system standardized by the International Commission on Illumination (CIE) in 1976. That is, a ^* , b ^* (a ^* , b ^* are chromaticities indicating hue and saturation) and L ^* (lightness) were measured. An X-Rite spectrophotometer type 938 was used as a measuring instrument, a light source for observation was a C light source, and a viewing angle was 2 °.

When the light resistance was confirmed according to JIS K7102, the image after 200 hours of light irradiation showed almost the same image density as in the initial stage and a slight change in hue.

An ultraviolet carbon arc lamp was used as the light source.

The change in hue was evaluated quantitatively on the basis of the following evaluation criteria for light resistance by obtaining the ΔE value of the following formula. ^{ΔE = {(L1 * -L2 *} ) 2 + (a1 * -a2 *) 2 + (b
1 ^* -b2 ^* ) ² } ^1/2 L1 ^* : lightness a1 ^* , b1 ^* of image before light irradiation: chromaticity L2 ^* indicating hue and saturation of image before light irradiation L2 ^* : of image after light irradiation Lightness a2 ^* , b2 ^* : Hue and saturation showing the hue and saturation of the image after light irradiation is evaluated as follows: A: ΔE is less than 4 after 200 hours irradiation, ΔE is less than 4 after 200 hours irradiation. 7 C: ΔE is 7 to 10 after irradiation for 200 hours D: ΔE is 10 or more after irradiation for 200 hours

The storage stability of the toner was evaluated by leaving it in an oven at 50 ° C. for 1 week. As the evaluation, the level of cohesiveness was visually determined. The toner cohesiveness evaluation criteria are shown below. A: Aggregates are not seen at all and flowability is very good. B: Aggregates are not seen at all. C: Some aggregates are seen but quickly disentangled. D: Aggregates are disentangled by a developer stirring device (normally). ) E: Aggregates cannot be sufficiently disentangled with the developer agitator (somewhat bad)

The results are shown in Table 3. As shown in Table 3, both OHP transparency and weather resistance were good.

Example 2 Same as Example 1 except that the binder resin (1) was replaced by 20 parts by mass of the binder resin (2) and 80 parts by mass of the binder resin (3). Thus, a magenta toner 2 and a magenta developer 2 are obtained. The toner measurement results are shown in Table 2.

Further, the toner was evaluated in the same manner as in Example 1. The image obtained in Example 2 was free from toner scattering, fog, and reduction in image density due to the durability test.
OHP transparency and weather resistance were also good. The results are shown in Table 3.

Example 3 Example 1 was repeated except that the binder resin (1) was replaced by 20 parts by mass of the binder resin (2) and 80 parts by mass of the binder resin (4). Similarly, magenta toner 3 and magenta developer 3 were obtained. The toner measurement results are shown in Table 2.

Further, the toner was evaluated in the same manner as in Example 1. The image obtained in Example 3 was free from toner scattering, fog, and reduction in image density due to the durability test.
OHP transparency and weather resistance were also good. The results are shown in Table 3.

<Example 4> Magenta toner 4 and magenta developer 4 were obtained in the same manner as in Example 1 except that the binder resin (5) was used in place of the binder resin (1). The toner measurement results are shown in Table 2.

Further, the toner was evaluated in the same manner as in Example 1. The image obtained in Example 4 was free from toner scattering, fog, and reduction in image density due to the durability test.
OHP transparency and weather resistance were also good. The results are shown in Table 3.

<Example 5> C. I. Pigment Red 5
7 instead of C.I. I. Cyan Toner 1 and Cyan Developer 1 were obtained in the same manner as in Example 1 except that Pigment Blue 15: 3 was used. The toner measurement results are shown in Table 2.

Further, the toner was evaluated in the same manner as in Example 1. The image obtained in Example 5 was free from toner scattering, fog, and reduction in image density due to the durability test.
OHP transparency and weather resistance were also good. The results are shown in Table 3.

<Example 6> C.I. I. Pigment Red 5
7 instead of C.I. I. A yellow toner 1 and a yellow developer 1 were obtained in the same manner as in Example 1 except that Pigment Yellow 180 was used. The toner measurement results are shown in Table 2.

Further, the toner was evaluated in the same manner as in Example 1. The image obtained in Example 5 was free from toner scattering, fog, and reduction in image density due to the durability test.
OHP transparency and weather resistance were also good. The results are shown in Table 3.

Comparative Example 1 Using the binder resin (2),
Magenta toner 5 and magenta developer 5 were obtained in the same manner as in Example 1 except that a benzophenone-based ultraviolet absorber was used. Table 3 shows the measurement results of the toner.

Further, in the same manner as in Example 1, magenta developer 5 was used for evaluation.

Due to the durability of the magenta toner 5 due to the ultraviolet absorber contaminating the sleeve and the photosensitive member, toner scattering, fog, and a decrease in image density occurred. Also, the OHP transparency was poor. Furthermore, the effect of the ultraviolet absorber was not so great. The results are shown in Table 3.

Comparative Example 2 Magenta toner 6 and magenta developer 6 were obtained in the same manner as in Example 1 except that the binder resin (6) was used in place of the binder resin (1). The toner measurement results are shown in Table 2.

Further, in the same manner as in Example 1, magenta developer 6 was used for evaluation.

The magenta toner 6 had poor OHP transparency, probably because the affinity between the colorant and the binder resin was not so good. Also, the weather resistance was poor. The results are shown in Table 3.

Comparative Example 3 Magenta toner 7 and magenta developer 7 were obtained in the same manner as in Example 1 except that the binder resin (3) was used in place of the binder resin (1). The toner measurement results are shown in Table 2.

Further, in the same manner as in Example 1, evaluation was carried out using magenta developer 7.

Magenta Toner 7 had remarkably poor weather resistance. The results are shown in Table 3.

Comparative Example 4 Example 1 was repeated except that the binder resin (1) was replaced by 20 parts by mass of the binder resin (6) and 80 parts by mass of the binder resin (7). Similarly, magenta toner 8 and magenta developer 8 were obtained. The toner measurement results are shown in Table 2.

Further, in the same manner as in Example 1, magenta developer 8 was used for evaluation.

Since the magenta toner 8 has a high acid value, the charging stability is deteriorated, and toner scattering, fog, and a decrease in image density occur. Further, the transparency of OHP was extremely poor.
The results are shown in Table 3.

<Comparative Example 5> Example 1 was repeated except that the binder resin (1) was replaced by 20 parts by mass of the binder resin (6) and 80 parts by mass of the binder resin (8). Similarly, magenta toner 9 and magenta developer 9 were obtained. The toner measurement results are shown in Table 2.

Further, in the same manner as in Example 1, magenta developer 9 was used for evaluation.

Since magenta toner 9 has a low Tm, its storability is significantly deteriorated. Also, the fixing temperature region became narrow. The results are shown in Table 3.

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[Table 1]

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[Table 2]

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[Table 3]

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According to the present invention, an image on which toner has been developed and fixed can be prevented from being affected by natural light or ultraviolet rays contained in lighting light even if left in a bright place for a long time. In addition, there is no contamination on the photosensitive member, sleeve, etc., which is a problem with the conventional developer to which the UV-resistant agent is added.
HP transparency can be exhibited.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Yojiro Hotta             3-30-2 Shimomaruko, Ota-ku, Tokyo             Non non corporation (72) Inventor Takaaki Uetaki             3-30-2 Shimomaruko, Ota-ku, Tokyo             Non non corporation F-term (reference) 2H005 AA01 AA21 CA02 CA28 CA30                       EA06 EA10

Claims (4)

[Claims] 1. A color toner containing at least a binder resin and a colorant, wherein the toner has an acid value of 5 to 45 mgKOH / g, and the resin component of the toner has a molecular weight measured by gel permeation chromatography (GPC). In the distribution, the number average molecular weight (Mn) is 1,000 to 100,000, the colorant contains nitrogen, the binder resin is a copolymer having nitrogen, and the toner is tetrahydrofuran (THF). The color toner is characterized in that the solution containing the soluble component extracted by Soxhlet extraction in Step 1 has a light transmittance of not more than 20% at a wavelength of 350 nm by UV-visible spectroscopy. 2. The color toner according to claim 1, wherein the binder resin is a copolymer having a UV resistant monomer. 3. The UV resistant monomer is a binder resin 100.
The color toner according to claim 2, which is contained in an amount of 0.01 to 20 parts by mass with respect to parts by mass. 4. The ultraviolet-resistant monomer contains at least one selected from the group consisting of nitrogen-containing ultraviolet-resistant monomers, the derivatives, and mixtures thereof.
Or the color toner according to item 3.