JP3458171B2 - Cyan toner for electrophotography - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel toner for developing an electrostatic charge image in electrophotography, electrostatic recording and the like, and more particularly to a cyan toner suitable for color electrophotography.

[0002]

2. Description of the Related Art An electrophotographic system in which an electric latent image is developed with a developer to form a visible image forms an electric latent image on a photoconductor made of a photoconductive material, and then the latent image is developed with a developer. After developing and transferring the toner powder image to paper or the like as required, the toner image is fixed by heating, pressing or the like to obtain a visible image.
Further, in order to obtain a multicolor image of color, an image obtained by exposing a document using a color separation filter or an image read by a scanner is laser-written and exposed, and the above steps are performed in yellow, magenta, and cyan. The color image is formed by superposing the toner images on each other using the color developer of.

As conventional cyan toner for electrophotography,
It is obtained by kneading a pigment such as copper phthalocyanine and a charge control agent together with a thermoplastic resin and pulverizing. However, since the cyan toner produced in this manner exists in the toner in a dispersed state as pigment particles, light scattering is caused by the dispersed particles and the transparency of the toner is lowered. For this reason,
The color reproducibility of an image in which a plurality of toners are superimposed is poor, and
The toner image transferred and fixed on the HP has a drawback that the projected image is dark and the saturation is low.

On the other hand, Japanese Unexamined Patent Publication Nos. 62-273570, 64-29855, and 1-28486.
No. 5, in place of the pigment, C.I. I. There is a proposal to increase transparency by using Solvent Blue 35, indophenol or anthraquinone dye. However, if these dyes are melt-kneaded together with the resin, a part of the pigment is thermally decomposed, the color tone of the pigment is changed, or the dye is not sufficiently dispersed, resulting in low saturation. It is difficult to control kneading conditions.

[0005]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a cyan toner for electrophotography, in which the above-mentioned drawbacks are improved. That is, it is to provide a cyan toner for electrophotography, which has good spectral reflection characteristics, transparency, and light resistance.

[0006]

According to the present invention, firstly, in a toner for electrophotography containing a thermoplastic resin and a colorant as main components, the colorant is represented by the following general formula (I) or (I
Provided is a cyan toner for electrophotography, which is a compound represented by I).

[Chemical 1] (In the formula (I), R ¹ represents a hydrogen atom or an alkoxy group.
R ² represents an alkoxy group or a dialkylamino group.
R ³ is a hydrogen atom, a halogen atom, an alkyl group or an alkyl group.
Represents a lucoxy group, M is zinc, nickel or copper, gold
Represents a genus atom, X represents an anion, and n represents a number of 2.
Represent. )

[Chemical 2] (In the formula (II), R ¹ represents a hydrogen atom or an alkoxy group.
R ² represents a hydrogen atom or a dialkylamino group,
R ³ is a hydrogen atom, a halogen atom, an alkoxy group or ace
Represents a tomido group, M is nickel, cobalt, iron or
Represents a metal atom of copper, X represents an anion, and n represents
Represents the number 2. ) Second, the volume average particle diameter (Dv) of the thermoplastic resin is 3 to 9 μm, and the ratio (Dv / Dp) to the number average particle diameter (Dp) is in the range of 1.00 to 1.15. Further, there is provided the electrophotographic cyan toner described in the first, which is dyed with the colorant represented by the general formula (I) or (II). Thirdly, the coloring agent is represented by the general formula (I) or (II)
There is provided a cyan toner for electrophotography as described in the above first or second, which is a mixture of a dye represented by the following formula and an anthraquinone dye. Fourthly, there is provided the electrophotographic cyan toner according to any one of the first to fourth aspects, wherein a layer of a releasing material is provided on the surface of the electrophotographic cyan toner particles.

That is, the cyan toner for electrophotography of the present invention contains the compound represented by the general formula (I) or (II) as a colorant, and thus has excellent spectral reflection characteristics, transparency and light resistance. Will be things.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below. As the thermoplastic resin used for the powder particles of the toner of the present invention, conventionally known ones can be widely used. For example, styrene, parachlorostyrene, vinyltoluene, vinyl chloride, vinyl acetate, vinyl propionate, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate. , Isobutyl (meth) acrylate, tert-butyl (meth) acrylate, dodecyl (meth) acrylate, 2-ethylhexyl (meth) acrylate,
Lauryl (meth) acrylate, (meth) acrylic acid 2-
Hydroxyethyl, glycidyl (meth) acrylate,
Hydroxypropyl (meth) acrylate, benzyl (meth) acrylate, furfuryl (meth) acrylate,
2-Chloroethyl (meth) acrylate, (meth) acrylonitrile, (meth) acrylamide, (meth) acrylic acid, vinyl methyl ether, vinyl ethyl ether,
Vinyl isobutyl ether, vinyl methyl ketone, N-
Examples thereof include polymers of monomers such as vinylpyrrolidone, N-vinylpyridine and butadiene, copolymers of two or more kinds of these monomers, or a mixture thereof.
Other polyesters, polyurethanes, polyamides, epoxy resins, rosins, modified rosins, terpene resins, phenol resins, aliphatic or alicyclic hydrocarbon resins, aromatic petroleum resins and the like can be used alone or in combination.

As a method for obtaining a toner, a coloring agent of the present invention [that is, a dye represented by the general formula (I) or (II), or the general formula (I) or (II) dye and anthraquinone dye] are mixed and kneaded and pulverized, or suspension polymerization, emulsion polymerization, a method of dyeing with the coloring agent of the present invention using polymer particles obtained by dispersion polymerization method, etc. However, in the present invention, the method of dyeing the resin particles obtained by the dispersion polymerization method with the colorant of the present invention is preferable.

As the dyes represented by the above general formulas (I) and (II) of the present invention, generally known dyes can be used. Typical examples are shown in [Table 1- (1)] and [Table 1- (2)] below.

[0011]

[Table 1- (1)]

[0012]

[Table 1- (2)]

It is also possible to use a mixture of two or more of the above colorants or a mixture with another blue colorant. As the blue colorant to be mixed and used, anthraquinone type oil-soluble dyes and disperse dyes are particularly preferable. The amount of the colorant of the present invention added is 0.3 to 100 parts by weight of the thermoplastic resin.
10 parts by weight, preferably 0.5 to 5 parts by weight.

Further, a charge control agent or a release agent may be added to the toner of the present invention, if necessary. As the charge control agent, for example, when it is negatively charged, a metal chelate of alkylsalicylic acid or naphthoic acid, JP-A-55-76353 is used.
And fluorine-containing compounds described in JP-A-3-213877, etc., and when positively charged, a quaternary ammonium salt and alkyl metal oxides described in JP-A-56-164350. Etc. can be used. As the release agent, low molecular weight polyolefins such as low molecular weight polyethylene, low molecular weight polypropylene and polyethylene oxide, natural waxes such as beeswax, carnauba wax and montan wax, higher fatty acids such as stearic acid, palmitic acid and myristic acid. In addition, metal salts of higher fatty acids, higher fatty acid amides and the like can be used. The release agent can exhibit more effects by forming a layer on the toner surface.

When a carrier is used as the developer, any conventionally known one can be used. For example, surface-oxidized or non-oxidized metals such as iron, nickel, copper, zinc, cobalt, manganese, and chromium, alloys or oxides thereof, and ferrites composed of the above metals can be used. Those coated with etc. can also be used. Further, for the developer in which the toner of the present invention is used, a fluidity modifier such as colloidal silica is added to the toner in an amount of 0.01 to
You may add about 3 weight part.

The cyan toner of the present invention has a volume average particle diameter (Dv) of 3 to 9 μm and a ratio (Dv / Dp) to the number average particle diameter (Dp) of 1.00 to 1.15. It is preferable. A dispersion polymerization method is preferable as a method for producing such a toner having a small particle size and a narrow particle size distribution. As a method for dyeing resin particles with a colorant, a method of dyeing by heating a dye and resin particles dispersed in water,
There is a solvent dyeing method in which a dye is dissolved or dispersed in an organic solvent and the resin particles are dyed in the solvent. When dyeing with the colorant of the present invention, the solvent dyeing method is preferable. The solvent used here can be a general-purpose organic solvent, but alcohol solvents such as methanol, ethanol, n-propyl alcohol, iso-propyl alcohol, n-butyl alcohol, iso-butyl alcohol, and tert-butyl alcohol are preferable. Depending on the solubility of the resin, other solvents or water may be added to the above alcohol solvent for dyeing in a mixed system,
It is also possible to dye with a system to which a surfactant or alcohol-soluble polymer is added.

[0017]

EXAMPLES The present invention will be described below in more detail with reference to examples, but the present invention is not limited thereto. All parts shown below are based on weight.

Example 1 Polyester resin (Tg 58 ° C., softening point 68 ° C.) 100
Part, 2 parts of the exemplified compound and 4 parts of zinc 3,5-ditertiarybutylsalicylate are kneaded by heating with a hot roll, pulverized and classified to obtain a volume average particle diameter of 8.5 μm.
m powder particles were obtained.

To 100 parts of this powder, 0.5 part of silica was added to prepare a cyan toner having silica on the particle surface. Next, 3 parts of this toner was mixed with 100 parts of the iron powder carrier to obtain a developer. This developer was placed in a magnetic brush developing device, and a copying test was conducted using a digital electrophotographic device having an organic photoconductor to obtain a clear cyan color copied image having good spectral characteristics. To examine the light resistance of this copied image, a part of the image was shielded from light and exposed to a xenon light source for 10 hours. Further, the haze degree of the copied image transferred to the polyester film was measured. The results are shown in Table 2.

Example 2 55 parts of styrene and 45 parts of methyl acrylate were copolymerized in a methyl alcohol solvent in the presence of polyvinylpyrrolidone as a dispersion stabilizer to give a volume average particle diameter (Dv) of 4.
Spherical powder particles having a narrow particle size distribution of 8 μm and a ratio Dv / Dp to the number average particle diameter (Dp) of 1.10 were obtained. Next, 100 parts of the powder particles are dispersed in 400 parts of methyl alcohol, 1.5 parts of the above-exemplified compound is added with stirring at room temperature, and the mixture is stirred at 50 ° C. for 3 hours for dyeing,
At room temperature, 20 parts of a 10% methanol solution of perfluoroalkyl sulfonic acid (Megafuck F-110 manufactured by Dainippon Ink and Chemicals, Inc.) was added, stirred for 30 minutes, filtered, and dried.
Cyan toner was obtained.

To 100 parts of this toner, 0.5 part of silica was added to prepare a cyan toner having silica on the surface of toner particles. Next, 3 parts of this toner was mixed with 100 parts of iron powder carrier to form a two-component developer, and an image was formed using a digital copying machine. As a result, a clear cyan having excellent dot reproducibility and good spectral characteristics was obtained. I got an image. The light resistance of this copied image was examined in the same manner as in Example 1. Further, the haze degree of the copied image transferred to the polyester film was measured.
The results are shown in Table 2.

Example 3 A styrene-maleic anhydride copolymer was dissolved in a mixed solvent of methyl alcohol and water, and 55 parts of styrene and 45 parts of methyl acrylate were copolymerized therein. The volume average particle diameter (Dv) was 3.7 μm, and the ratio Dv / Dp to the number average particle diameter (Dp) was 1.12. Next, 1.2 parts of the above-exemplified compound and C.I. I. Solvent Blue 1
After adding 4 and 0.8 parts and stirring at 50 degreeC for 3 hours and dyeing, it filtered and dried and the particle colored in cyan was obtained. Next, 100 parts of the dyed particles are mixed with water-methanol (1:
1) Redispersion in 300 parts of mixed solvent, 2 parts of perfluoroalkyl phosphoric acid were added and mixed by stirring, and the solvent was removed by a spray dryer to obtain a cyan toner.

Next, 3 parts of this toner is used as an iron powder carrier 10
When a two-component developer was mixed with 0 parts to form an image using a digital copying machine, a cyan image having excellent dot reproducibility and good spectral characteristics was obtained. The light resistance of this copied image was examined in the same manner as in Example 1. In addition, the developer,
Transfer to polyester film using a digital copier,
After fixing, the haze of the image was measured. The results are shown in Table 2. When this image was projected by an overhead projector (OHP), a clear cyan image was projected.

Example 4 Cyan particles 100 polymerized and dyed in the same manner as in Example 3
Parts are redispersed in 300 parts of water-methanol (1: 1) mixed solvent, 2 parts of perfluoroalkylphosphoric acid and 2 parts of carnauba wax emulsion are added and mixed by stirring, and the solvent is removed by a spray dryer to remove cyan. Toner was obtained.

Next, 3 parts of this toner is transferred to an iron powder carrier 10
An image was formed using a digital copying machine equipped with a fixing roller that does not use oil such as silicone oil by mixing with 0 part to form a two-component developer.
In the range of 0 to 210 ° C., there was no paper winding or offset phenomenon, and a cyan image with excellent dot reproducibility and good spectral characteristics was obtained. Further, the light resistance and the haze degree were measured in the same manner as in Example 1. The results are shown in Table 2.

Comparative Examples 1 to 2 Instead of the compound of Example 1, CI. Pigment
Blue 15 (Comparative Example 1), CI. Dispers
A toner was prepared in the same manner as in Example 1 except that eBlue 354 (Comparative Example 2) was used to obtain a copied image.
The results are shown in Table 2.

Comparative Example 3 Instead of the compound of Example 2, CI. Dispers
A toner was prepared in the same manner as in Example 2 except that eBlue 354 was used, and a copied image was obtained in the same manner as in Example 2. The results are shown in Table 2.

[0028]

[Table 2] ○: Almost no color change ×: Color change

[0029]

Since the cyan toner for electrophotography of the present invention has the above-mentioned constitution, it has a good spectral reflection characteristic, an excellent light resistance, and a transparent and clear projection image when copied on an OHP sheet. Is obtained.

─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A 64-29855 (JP, A) JP-A 63-227569 (JP, A) JP-A 61-292644 (JP, A) JP-A 59- 177571 (JP, A) JP-A-8-123085 (JP, A) JP-A-8-114949 (JP, A) JP-A-7-175267 (JP, A) JP-A-7-175259 (JP, A) JP 5-216227 (JP, A) JP 5-181316 (JP, A) JP 5-169840 (JP, A) JP 5-142863 (JP, A) JP 5-17701 (JP, A) JP-A-4-283758 (JP, A) JP-A-3-103476 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) G03G 9/08 CA (STN ) REGISTRY (STN)

Claims (4)

(57) [Claims] 1. An electrophotographic toner mainly comprising a thermoplastic resin and a colorant, wherein the colorant is a compound represented by the following general formula (I) or (II). Cyan toner. [Chemical 1] (In the formula (I), R ¹ represents a hydrogen atom or an alkoxy group.
R ² represents an alkoxy group or a dialkylamino group.
R ³ is a hydrogen atom, a halogen atom, an alkyl group or an alkyl group.
Represents a lucoxy group, M is zinc, nickel or copper, gold
Represents a genus atom, X represents an anion, and n represents a number of 2.
Represent. ) [Chemical 2] (In the formula (II), R ¹ represents a hydrogen atom or an alkoxy group.
R ² represents a hydrogen atom or a dialkylamino group,
R ³ is a hydrogen atom, a halogen atom, an alkoxy group or ace
Represents a tomido group, M is nickel, cobalt, iron or
Represents a metal atom of copper, X represents an anion, and n represents
Represents the number 2. ) 2. The volume average particle diameter (D) of the thermoplastic resin.
v) is 3 to 9 μm, the ratio (Dv / Dp) to the number average particle diameter (Dp) is in the range of 1.00 to 1.15, and is represented by the general formula (I) or (II). The cyan toner for electrophotography according to claim 1, wherein the cyan toner is dyed with a colorant. 3. The coloring agent is represented by the general formula (I) or (I
The cyan toner for electrophotography according to claim 1 or 2, which is a mixture of a dye represented by I) and an anthraquinone dye. 4. A layer of a releasable material is provided on the surface of the electrophotographic cyan toner particles.
3. The cyan toner for electrophotography according to any one of 3 above.