JP3136792B2 - Toner for developing electrostatic images - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrostatic image developing toner used in an electronic copying machine or the like.

[0002]

2. Description of the Related Art In a developing process, a developer used in an electronic copying machine or the like is once adhered to an image carrier such as a photoreceptor on which an electrostatic image is formed, and then is exposed to light in a transfer process. After being transferred from the body to the transfer paper, it is fixed on the copy paper surface in a fixing step. At this time, as a developer for developing an electrostatic image formed on the latent image holding surface, a two-component developer including a carrier and a toner and a one-component developer (magnetic toner) that does not require a carrier are used. )It has been known.

[0003] Conventionally, a nigrosine dye, a quaternary ammonium salt,
Charge control agents such as metal-containing complex dyes and carrier coating agents have been known. However, these conventional charge-imparting agents have a problem that the effect of imparting charge is not always sufficient, and in particular, the effect changes with time, so that copy smearing due to continuous copying occurs and the copy quality is reduced. Was.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a high-quality toner for developing an electrostatic image which is less likely to cause copy stains and the like over time.

[0005]

Means for Solving the Problems The present inventors have conducted intensive studies in order to solve the above-mentioned problems, and as a result, by incorporating a compound having a specific structure into the toner, these problems have been solved. And arrived at the present invention. That is, the present invention relates to an electrostatic image developing toner containing at least a resin and a colorant, wherein the toner comprises at least one cyclo-oligosaccharide or a derivative thereof.

Hereinafter, the present invention will be described in detail. The electrostatic image developing toner of the present invention is characterized by containing one or more cyclooligosaccharides or derivatives thereof. The cyclo-oligosaccharide generally refers to a monosaccharide obtained by condensation polymerization of 6 to 8 cyclic molecules due to loss of water molecules. Examples of the monosaccharide constituting the cyclo-oligosaccharide include glucose, fructose, xylose, galactose, mannose and arabinose.

The cyclo-oligosaccharides used in the present invention include cycloinulo-oligosaccharides composed of fructose,
Alternatively, cyclodextrin composed of glucose or a derivative thereof is particularly preferable, and is a compound represented by the following general formula (I) or (II).

[0008]

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Wherein R ¹ , R ² and R ³ each represent a hydrogen atom, an alkyl group, an acyl group or the like;
Represents a number from 6 to 8. R ¹ , R ² , R
All ^three may be the same or different. ]

[0010]

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Wherein R ⁴ , R ⁵ and R ⁶ each represent a hydrogen atom, an alkyl group, an acyl group or the like;
m represents any number from 6 to 8. R ⁴ , R ⁵ ,
R ⁶ may be all the same or different. Specific examples of the substituents R ¹ , R ² and R ³ include a hydrogen atom; an alkyl group such as a methyl group, an ethyl group, a propyl group and a butyl group; An acyl group is mentioned, and among them, R ¹ is preferably a hydrogen atom, and R ² and R ³ are preferably methyl groups. Also, n is preferably 6.

Specific examples of the substituents R ⁴ , R ⁵ and R ⁶ include a hydrogen atom; an alkyl group such as a methyl group, an ethyl group, a propyl group and a butyl group; an acetyl group, a propionyl group, a butyryl group and an isobutyryl group. R ⁴ is preferably a hydrogen atom, and R ⁵ and R ⁶ are preferably methyl groups. Also, m is preferably 6. Also, R ¹ ,
When R ² and R ³ are all hydrogen atoms, the solubility in water becomes high, and there is a possibility that a slight problem may occur in the electric characteristics.

Among the cyclo-oligosaccharides or derivatives thereof represented by the general formula (I) or (II), specific examples suitable for inclusion in the toner for electrostatic image of the present invention are represented by the following structural formulas. However, the present invention is not limited thereto.

[0014]

[Table 1]

[0015] Such cyclo-oligosaccharides or derivatives thereof can be used in the present invention irrespective of the production method, but a specific production method is described in JP-A-2-2527.
No. 01 publication. As the resin component usable in the present invention, various known resin components suitable for the toner for developing an electrostatic image can be used. For example, styrene-based resins, styrene-acrylic copolymer resins, polyester-based resins, epoxy-based resins, and mixed resins thereof, and those having an amino group in the alkyl side chain, and the like are available.

The content of the cyclo-oligosaccharide or a derivative thereof in the toner is 0.1 to 20 parts by weight based on 100 parts by weight of the resin.
It is preferably 1 part by weight, more preferably 1 to 15 parts by weight. If the content of the cyclo-oligosaccharide or a derivative thereof is too small, the effect of improving the chargeability cannot be expected, and if it is excessive, the quality of the toner deteriorates, which is not preferable. The colorant used in the present invention is not particularly limited as long as it is conventionally used, and carbon black or the like is used to obtain a black toner. Cyclo-oligosaccharides or derivatives thereof are usually white, so blue, red,
It may be contained in a color toner such as yellow, and in this case, a colorant comprising a dye or pigment of a corresponding color is used.

The content of the colorant is preferably 3 to 20 parts by weight based on 100 parts by weight of the resin. Further, in addition to the cyclo-oligosaccharide or a derivative thereof, the toner of the present invention may contain other charge control agents including known ones, such as a nigrosine dye, a quaternary ammonium salt, and a gold-containing complex salt dye. May be included.

Other components of the toner of the present invention include:
In order to improve fixability and fluidity, additives such as a low molecular weight olefin polymer and finely divided silica may be added. The toner may be produced by kneading the above components in a kneader or the like, cooling, pulverizing and classifying. In addition to the two-component developer, the toner of the present invention can be applied to a so-called one-component developer (magnetic toner) such as an encapsulated toner, a polymerized toner, and a magnetite-containing toner.

The average particle size of the toner is preferably 5 to 20 μm. The carrier for forming the developer by mixing with the toner of the present invention is not particularly limited, but is preferably an iron powder having an average particle diameter of 10 to 200 μm. The particle size of the iron powder is not particularly limited. In this case, a so-called coated carrier coated with a fluorine-based resin or the like for the purpose of improving durability during continuous use can also be used. Further, other known carriers such as a ferrite-based or magnetite-based carrier can also be used. These carriers are preferably used in an amount of 5 to 100 parts by weight based on 1 part by weight of the toner.

[0020]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, which should not be construed as limiting the scope of the invention. In the following examples, “parts” simply means “parts by weight”.

[0021]

Example 1 100 parts of styrene resin (SBM-600, manufactured by Sanyo Kasei Co., Ltd.) 10 parts of carbon black (# 44 manufactured by Mitsubishi Kasei Co., Ltd.) 2 parts of exemplified compound (1)

The above-mentioned materials were mixed and kneaded, and pulverized and classified to obtain a black positively charged toner having an average particle diameter of 11 μm. 5 parts of this toner and 100 parts of a fluororesin-coated carrier having an average particle diameter of about 100 μm were mixed and stirred to prepare a developer. Next, when this developer was actually photographed with a copying machine using an organic photoconductor as a photoreceptor, a clear copy with less background stains, so-called fog, was obtained.

Example 2 The procedure of Example 1 was repeated, except that 1 part of Exemplified Compound (2) was used instead of 2 parts of Exemplified Compound (1) as a charge controlling agent. A good copy was obtained in the same manner as described above.

Example 3 The procedure of Example 1 was repeated, except that 3 parts of Exemplified Compound (4) was used instead of 2 parts of Exemplified Compound (1) as a charge controlling agent. A good copy was obtained in the same manner as described above.

Example 4 The procedure of Example 1 was repeated except that 5 parts of Exemplified Compound (7) was used instead of 2 parts of Exemplified Compound (1) as a charge controlling agent. A good copy was obtained in the same manner as described above.

Example-5 Except that 3 parts of Exemplified Compound (10) was used instead of 2 parts of Exemplified Compound (1) as a charge controlling agent, the procedure of Example-1 was repeated. A good copy was obtained in the same manner as described above.

Example -6 The same procedure as in Example 1 was carried out except that 2 parts of Exemplified Compound (11) was used instead of 2 parts of Exemplified Compound (1) as a charge controlling agent. A good copy was obtained in the same manner as described above.

Example -7 The same procedures as in Example 1 were carried out except that 3 parts of Exemplified Compound (13) were used instead of 2 parts of Exemplified Compound (1) as a charge controlling agent. A good copy was obtained in the same manner as described above.

Example-8 Except that 4 parts of Exemplified Compound (16) was used instead of 2 parts of Exemplified Compound (1) as a charge controlling agent, the procedure of Example 1 was repeated. A good copy was obtained in the same manner as described above.

Example -9 Example 1 was carried out in exactly the same manner as in Example 1 except that 3 parts of Exemplified Compound (18) was used instead of 2 parts of Exemplified Compound (1) as a charge controlling agent. A good copy was obtained in the same manner as described above.

Example 10 The procedure of Example 1 was repeated, except that 4 parts of Exemplified Compound (20) were used instead of 2 parts of Exemplified Compound (1) as a charge controlling agent. A good copy was obtained in the same manner as described above.

[0032]

The toner for developing an electrostatic image of the present invention is a high-quality toner for developing an electrostatic image, which does not cause stains on a copy in continuous copying.

Continuation of front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G03G 9/08

Claims (1)

(57) [Claims] 1. An electrostatic image developing toner comprising at least a resin and a colorant, comprising at least one cyclooligosaccharide or a derivative thereof.