JPH05265247A - Positively chargeable capsule type toner - Google Patents

Abstract

(57) [Summary] [Structure] For example, various cationic self-water-dispersible resins represented by vinyl resins, polyester resins and / or urethane resins having a tertiary amino group, and coloring materials. The present invention aims to provide a positively chargeable capsule type toner comprising [Effect] By using a cationic self-water dispersible resin having a tertiary amino group as a hydrophilic group in the resin,
It is possible to obtain a positively chargeable capsule type toner in which the colorant is uniformly dispersed in the particles without using a dispersion stabilizer. In the toner particles according to the present invention, the particle size can be easily controlled and the normal distribution can be achieved by the amount of the tertiary amino group that neutralizes the tertiary amino group. Furthermore, by using various cationic self-water-dispersible resins, resins having desired characteristics can be obtained very easily.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a novel and useful positively charged capsule type toner. More specifically, the present invention relates to a novel positively chargeable capsular toner comprising a cationic self-water-dispersible resin and a colorant, and in particular, a specific toner that can be used for toner electrostatic latent image. Regarding

[0002]

2. Description of the Related Art As a powder toner for forming an electrostatic latent image into a visible image, a coloring material, an additive, etc. are kneaded and melted in a toner resin to be dispersed, and after cooling,
It is a general method to mechanically grind and obtain this.

However, the toner obtained by such a method has a variation in electric characteristics due to non-uniformity when mixing colorants and additives, or a flow due to an irregular particle shape. At present, there are various problems such as poor productivity, low yield in reducing the particle size, and mechanical limitations.

In addition, in the case of such a general method, also in production, whether it is melt-kneading or crushing,
The difficulty is that the energy consumption required for them is enormous.

As a method other than the so-called pulverization method as described above, various polymerization methods have been studied. However, all of these improving means, since the monomer and the colorant and additives are mixed and dispersed to perform polymerization,
It is extremely difficult to uniformly include a coloring material, an additive, etc. in the particles.

Further, the addition of a dispersion stabilizer is indispensable,
Therefore, the influence of the addition thereof on the electrical characteristics and fluidity is just inevitable. Moreover, it is very costly to wash the dispersion stabilizer in question.

As described above, even by the conventional polymerization method,
Since the manufacturing process itself becomes complicated, and in addition, defects due to the manufacturing process are generated, a sufficiently satisfactory toner cannot be obtained.

[0008]

As described above, as a matter of fact, it is impossible to obtain a satisfactory toner as long as the conventional technique is followed.

Therefore, the inventors of the present invention have proposed Japanese Patent Application No. 2-2.
No. 60025, by applying the new encapsulation method, further develop the new capsule-type toner and manufacturing method using self-water-dispersible resin,
A new proposal was made as Japanese Patent Application No. 3-224227, thereby solving the problems of the pulverization method and the polymerization method.

In this case, since the self-water-dispersible resin is an anion type resin having an acid group in the hydrophilic group, a negatively chargeable capsule type toner can be easily obtained by this method. Was to be

However, when such anionic self-water-dispersible resin is used as a binder resin for a toner, it is not possible to impart a stable positive chargeability to the toner once obtained. However, the fact is that the production of positively chargeable capsule type toner has not been achieved so far.

[0012]

Therefore, the present inventors have
In view of the existence of the drawbacks in the conventional technology as described above,
In order to solve such problems, the present invention provides a novel technique in which a cationic self-water dispersible resin is used as a binder resin for positively charged capsule toner in order to solve the above problems. Therefore, I earnestly started research.

Therefore, an object of the present invention is to provide a positively chargeable capsule type toner.

That is, the present invention is basically intended to provide a positively chargeable capsule type toner comprising a cationic type self-water-dispersible resin and a colorant, and specifically, the present invention. Is to provide various positively chargeable capsule type toners each having a tertiary amino group and represented by a vinyl resin, a polyester resin and / or a urethane resin, respectively.

Here, the above-mentioned cationic self-water dispersible resin used in the present invention is one in which a tertiary amino group, for example, is introduced into the resin as a hydrophilic group, and When a cationic group such as a tertiary amino group is neutralized with an organic acid or an inorganic acid, it becomes a cation in an aqueous medium to exhibit hydrophilicity and an average particle size of 0.1 micron ( μm)
Those having the dispersibility of self-dispersion are referred to the following levels.

Specific examples of such cationic self-water dispersible resins include vinyl resins, polyester resins, urethane resins, and the like, and a mixture of two or more kinds of these resins. Of course, it may be used (combined use).

First, in the above vinyl-based resin, the hydrophilic group, for example, the tertiary amino group, has a tertiary amino group, for example, dimethylaminoethyl acrylate or diethylaminoethyl methacrylate. Various polymerizable monomers such as typical alkyl acrylates or methacrylates, and other polymerizable monomers copolymerizable with the tertiary amino group-containing alkyl acrylates or methacrylates. It is introduced into the resin by polymerization.

In this case, as the other copolymerizable polymerizable monomers, those which do not have an acid group per se and which can be used as a binder for toner by the obtained polymer are used. Of course, any of them can be used without any special limitation.

When the above-mentioned cationic self-water-dispersible resin is a polyester resin, the tertiary amino group is a so-called tertiary one represented by, for example, 2,2'-methylaminodiethanol. It is introduced into the resin by condensing the amino group-containing diols with other diols and dicarboxylic acids.

Further, also when the above-mentioned cationic self-water-dispersible resin is a urethane resin, such a tertiary amino group is typified by, for example, 2,2'-methylaminodiethanol, so-called ternary amino group. Using a secondary amino group-containing diol, with an isocyanate compound,
It is introduced into the resin by reacting with other diols and / or polyols.

The amount of the amino group in the cationic self-water-dispersible resin is usually 20 to 400 mg equivalent / resin solid content 100 g, preferably 50 to 25.
The range of 0 mg equivalent / resin solid content 100 g is suitable.

The number average molecular weight of the resin is
A range of 3,000 to 100,000, preferably a range of 5,000 to 50,000 is suitable. Furthermore, the glass transition point of the resin is 30 to
The temperature in the range of 90 ° C. is preferable, and the temperature in the range of 50 to 70 ° C. is suitable.

Of course, the above-mentioned coloring material used in the present invention includes various kinds of dyes and pigments, which are so-called and commonly used, which have been used as toner materials, There is no limit.

[0024]

EXAMPLES Next, the present invention will be described more specifically by way of examples, but the present invention is by no means limited to these examples. In the following,
Parts and% are based on weight unless otherwise specified.

Example 1 200 parts of methyl ethyl ketone was placed in a reaction vessel and
Heated to 0 ° C. Then, the mixture in the proportions shown below was added dropwise over 2 hours. The reaction was performed under a nitrogen atmosphere.

Dimethyaminoethyl acrylate 20 parts 2-Ethylhexyl acrylate 12 parts Methyl methacrylate 68 parts “Perbutyl O” [NOF Corporation product] 3 parts

Thereafter, even after the above mixture was added dropwise, 0.5 part of "perbutyl O" was added to the reaction solution every two hours, and the reaction was continued at 80 ° C. . The polymerization rate after the reaction was 98%, and thus the target resin was obtained.

Example 2 300 parts of methyl ethyl ketone was placed in a reaction vessel and
Heated to 0 ° C. Then, the mixture in the proportions shown below was added dropwise over 2 hours. The reaction was performed under a nitrogen atmosphere.

Dimethylaminoethyl acrylate 10 parts 2-Ethylhexyl acrylate 12 parts Styrene 78 parts “Perbutyl O” 3 parts

Even after the dropping of the above mixture, every hour,
Divide into 2 parts and add 0.5 parts of "Perbutyl O"
In addition to the reaction solution, the reaction was allowed to continue at 80 ° C. The polymerization rate after completion of the reaction was 97%, and thus the target resin was obtained.

Example 3 For 675 parts (nonvolatile content = 40%) of the cationic self-water-dispersible resin obtained in Example 1, “ELFTEX 8” (carbon manufactured by Cabot Corporation of the United States) was used. 30 parts of (black) were mixed with "Eiger Motor Mill M-250" (manufactured by Eiger, USA) for 1 hour.

Next, 1.3 mol (mol) equivalent of acetic acid to the tertiary amino group in the resin and 50% by weight of acetone relative to the solid content were added thereto, and the three-one motor was turned on. Water was added dropwise while stirring at 350 RPM to effect phase inversion emulsification.

Then, the organic solvent was removed by distillation under reduced pressure, the acetic acid was neutralized with triethylamine, and dried with a spray dryer to obtain the intended toner particles.

The property values of the positively chargeable capsule type toner obtained in this embodiment are shown in Table 1.

Example 4 Dry particles of the desired positively chargeable capsule-type toner were obtained by the same method as in Example 3 except that the cationic self-water-dispersible resin according to Example 2 was used. Obtained.

Table 1 shows the property values of the positively chargeable capsule type toner obtained in this example. Further, when a test chart was copied using this toner, a reproducible image was obtained, and it was judged that it was just usable for practical use.

[0037]

[Table 1]

<< Footnote in Table 1 >> The average particle diameter is a weight average particle diameter measured by "Coulter Multisizer" (produced by Coulter, Inc., USA).

The amount of charge is 3 g of toner,
A value obtained by charging up a developer consisting of 97 g of "X211A" (a carrier manufactured by Fuji Electric Chemical Co., Ltd.) for 60 minutes at room temperature and normal humidity.

Further, the image was obtained as a result of a copying test using the above-mentioned developer with a "FS-8200" machine [a product of Sharp Corporation].

[0041]

By using a cationic self-water-dispersible resin having a tertiary amino group as a hydrophilic group in the resin, the coloring agent can be incorporated into the particles without using a dispersion stabilizer.
It is possible to obtain a positively chargeable capsule type toner uniformly dispersed.

The toner particles according to the present invention have a normal distribution because the particle size can be easily controlled by the amount of the tertiary amino group that neutralizes the tertiary amino group.

Further, by using various cation type self-water dispersible resins, resins having desired characteristics can be obtained. Moreover, of course, any colorant can be used.

Furthermore, in the positively chargeable capsule type toner of the present invention, since the particle surface is completely covered with the resin, the surface electric value is not affected by the coloring material, and the color is not affected. Corresponding to the toner can be done very easily.

Claims (5)

[Claims] 1. A positively chargeable capsule-type toner comprising a cationic self-water-dispersible resin and a colorant. 2. The toner according to claim 1, wherein the cationic self-water dispersible resin is a vinyl resin. 3. The toner according to claim 1, wherein the cationic self-water dispersible resin is a polyester resin. 4. The toner according to claim 1, wherein the cationic self-water-dispersible resin is a urethane resin. 5. The cation-type self-water-dispersible resin as described above, wherein a tertiary amino group is introduced.
4. The toner according to any one of 4 above.