JP3264065B2 - 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 composed of a carrier and a toner and a one-component developer (magnetic toner) not requiring a carrier are used.
It has been known.

[0003] Conventionally, a charge controlling agent such as a nigrosine dye, a quaternary ammonium salt, a coating agent for a carrier, and the like have been known as agents that impart a chargeability to a developer (for example, Japanese Patent Application Laid-Open No. 4-125655). Gazette, U.S. Pat. No. 5,151,338).

[0004]

However, these conventional charge-imparting agents do not always have a sufficient effect of imparting the chargeability, and in particular, the effect changes with time, so that copy contamination due to continuous copying occurs and the copy quality is reduced. There was a problem that it decreased.

[0005]

The inventors of the present invention have conducted intensive studies to provide a high-quality toner for developing an electrostatic charge image which is less likely to cause copy stains even after a lapse of time.
It has been found that by incorporating a compound having a specific structure into the toner, these problems can be solved.
The present invention has been reached.

That is, the gist of the present invention is characterized in that an electrostatic image developing toner containing at least a resin and a colorant contains at least one compound represented by the following general formula (I). The toner for developing electrostatic images.

[0007]

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(Wherein R ₁ represents a substituted or unsubstituted alkyl group having 1 to 24 carbon atoms or a substituted or unsubstituted aralkyl group, and R ₂ , R ₃ and R ₄ each represent:
Represents a substituted or unsubstituted alkyl group or a substituted or unsubstituted aralkyl group having 2 to 24 carbon atoms. A represents an aromatic ring residue which may have a substituent. )

Hereinafter, the present invention will be described in detail. The toner for developing an electrostatic image of the present invention is characterized in that it contains at least one compound represented by the above general formula (I).

Specific examples of the substituent R ₁ include a methyl group,
Ethyl group, n-propyl group, iso-propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group,
Alkyl groups such as tridecyl group, tetradecyl group, pentadecyl group, hexadecyl group, heptadecyl group, stearyl group, nonadecyl group, eicosyl group, docosyl group, tetracosyl group; hydroxyl-substituted alkyl group, halogen-substituted alkyl group, alkoxyl-substituted alkyl group Aralkyl groups such as a benzyl group and a phenethyl group;
Lower alkyl group-substituted aralkyl groups, nitro group-substituted aralkyl groups, substituted aralkyl groups such as halogen-substituted aralkyl groups, among others, methyl group, benzyl group, lower alkyl group-substituted benzyl group, nitro group-substituted benzyl group,
Halogen-substituted benzyl groups are preferred.

R ₂ , R ₃ and R ₄ are ethyl, n-propyl, iso-propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl Group, tridecyl group, tetradecyl group, pentadecyl group, hexadecyl group, heptadecyl group, stearyl group, nonadecyl group, eicosyl group,
Alkyl groups such as docosyl group and tetracosyl group; substituted alkyl groups such as hydroxyl-substituted alkyl group, halogen-substituted alkyl group, alkoxyl-substituted alkyl group; benzyl group;
Aralkyl groups such as phenethyl groups; and substituted aralkyl groups such as lower alkyl-substituted aralkyl groups, nitro-substituted aralkyl groups, and halogen-substituted aralkyl groups. Usually, an unsubstituted alkyl group having 2 to 16 carbon atoms or a benzyl group is preferred.

[0012] Since the methyl group increases the water solubility, many of the methyl groups do not precipitate in water due to salt exchange in the general synthesis method described below. On the other hand, if only one of R ₂ , R ₃ , and R _{4 is used} as an organic group having a large number of carbon atoms, the organic group is insoluble in water and is often obtained as a crystal. Tend to. Preferably, it is an alkyl group having 12 or less carbon atoms, and the difference in carbon number between R ₂ , R ₃ and R ₄ is 4 or less. Particularly preferably, R ₂ , R ₃ and R ₄ are the same group. Specifically, a butyl group, an octyl group, a decyl group, and a dodecyl group are preferable, and an n-butyl group,
An n-octyl group is particularly preferred.

A represents an aromatic ring residue which may have a substituent, and includes an arylene group such as a phenylene group, a naphthylene group and an anthrylene group, and a phenylene group and a naphthylene group are particularly preferred. These may have a substituent, and examples of the substituent include an alkyl group, a hydroxyl group, an amino group and a halogen group, and a hydroxyl group is particularly preferable. Among the compounds represented by the above general formula (I), specific examples of compounds suitable for inclusion in the toner for developing an electrostatic image of the present invention include compounds represented by the following structural formulas. However, the present invention is not limited to these. Illustrative compounds

[0014]

[Table 1]

[0015]

[Table 2]

[0016]

[Table 3]

[0017]

[Table 4]

[0018]

[Table 5]

[0019]

[Table 6]

The compound represented by the general formula (I) can be used in the present invention regardless of the production method. An example of the specific production method will be described below. General formula (I)
The compound represented by the general formula (II) is, for example, a compound represented by the general formula (II)

[0021]

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A quaternary ammonium halide compound represented by the following general formula (III):

[0023]

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(Wherein A has the same meaning as in the general formula (I), and Y represents an alkali metal such as sodium, potassium, etc.) and reacted in water or alcohol by heating to about 50 to 70 ° C. It can be obtained by:

The resin component usable in the present invention includes:
Various known toners suitable for the electrostatic image developing toner 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 compound represented by the general formula (I) in the toner is preferably 0.1 to 20 parts by weight, more preferably 1 to 20 parts by weight based on 100 parts by weight of the resin.
15 parts by weight.

If the content of the compound represented by the general formula (I) 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. Also,
Since the compound represented by the general formula (I) is usually white,
It may be contained in color toners such as blue, red and yellow,
In this case, a colorant composed of 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, the toner of the present invention contains, in addition to the compound represented by the general formula (I), other charge control agents including known ones, such as a nigrosine dye, a quaternary ammonium salt, and a polyamine resin. You may do it.

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. As a method for producing the toner, the above components may be kneaded in a kneader or the like, cooled, pulverized and classified. 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 or silicon-based resin for the purpose of improving durability during continuous use can 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.

[0030]

EXAMPLES Hereinafter, the present invention will be described in more detail by way of examples, but the present invention is not limited to the following examples unless it exceeds the gist thereof. In the following, the term “parts” simply means “parts by weight”.

Example 1

[Table 7] Styrene acrylic resin (styrene / acryl = 8/2) 100 parts Carbon black (MA-100 manufactured by Mitsubishi Chemical Corporation) 6 parts Low molecular weight polyethylene 1 part Low molecular weight polypropylene 1 part Exemplary compound (8) 2 Part The above compounds are compounded and kneaded, and crushed and classified to obtain an average particle size of 1
1 μm black toner was obtained. 0.2 part of hydrophobic silica was mixed with 100 parts of the toner to obtain a toner.
4 parts of this toner and 100 parts of a silicone resin-coated carrier (ferrite) having an average particle diameter of 100 μm were mixed and stirred to prepare a developer.

Next, when this developer was actually photographed by a copying machine using an organic photoconductor as a photoreceptor, a clear copy with little background fouling, so-called fog, was obtained. Initial image density is 1.37, fog is 0.84, charge amount is 1.
It was 5.3 μc / g. Further, a copy test was performed on 100,000 sheets. As a result, the image density was 1.37, the fog was 0.87, and the charge amount was 18.5.
μc / g.

Example 2 Example 1 was carried out in exactly the same manner as in Example 1 except that a silicone resin-coated carrier having an average particle diameter of 100 μm and having magnetite as a core was used as a coating carrier. A good copy was obtained in the same manner as described above. Initial charge amount, 10
After 000 sheets, the charge amounts were 14 μc / g and 1 respectively.
It was 9 μc / g. The initial image density is 100,000
It was 1.35 after each sheet.

Example 3 The procedure of Example 1 was repeated except that a fluororesin-coated carrier having an iron core and having an average particle size of 70 μm was used as a coating carrier. Good copies were obtained as well.

Example 4

[Table 8] Styrene resin 100 parts (manufactured by Sanyo Chemical Co., trade name: SBM-600) Carbon black 10 parts (Mitsubishi Kasei Co., Ltd. # 44) Exemplary compound (1) 3 parts

The above materials were blended and kneaded, and crushed and classified to obtain a black toner having an average particle size of 11 μm. 5 parts of this toner and 100 parts of a silicone-based resin-coated carrier (ferrite) having an average particle size of about 100 μm were mixed and stirred to prepare a developer. Next, when this developer was actually photographed by a copying machine using an organic photoconductor as a photoconductor, a white background was stained,
A clear copy with little so-called fog was obtained.

Example 5 The procedure of Example 4 was repeated except that 3 parts of Exemplified Compound (4) was used instead of 3 parts of Exemplified Compound (1) as a charge controlling agent. Good copies were obtained as in Example 4.

Example 6 The procedure of Example 4 was repeated except that 2 parts of Exemplified Compound (5) was used instead of 3 parts of Exemplified Compound (1) as a charge controlling agent.
Good copies were obtained as in Example 4.

Example 7 The procedure of Example 4 was repeated except that 2 parts of Exemplified Compound (6) was used instead of 3 parts of Exemplified Compound (1) as a charge controlling agent. Good copies were obtained as in Example 4.

Example 8 The procedure of Example 4 was repeated except that 2 parts of Exemplified Compound (7) was used instead of 3 parts of Exemplified Compound (1) as a charge controlling agent. Good copies were obtained as in Example 4.

Example 9 The procedure of Example 4 was repeated except that 2 parts of Exemplified Compound (8) was used instead of 3 parts of Exemplified Compound (1) as a charge controlling agent. Good copies were obtained as in Example 4.

Example 10 The procedure of Example 4 was repeated, except that 2 parts of Exemplified Compound (9) was used instead of 3 parts of Exemplified Compound (1) as a charge controlling agent. Good copies were obtained as in Example 4.

Example 11 The procedure of Example 4 was repeated except that 3 parts of Exemplified Compound (10) was used instead of 3 parts of Exemplified Compound (1) as a charge controlling agent. Good copies were obtained as in Example 4.

(Example-12) The procedure of Example-4 was repeated, except that 3 parts of Exemplified Compound (12) was used instead of 3 parts of Exemplified Compound (1) as a charge controlling agent. Good copies were obtained as in Example 4.

Example 13 The procedure of Example 4 was repeated except that 2 parts of Exemplified Compound (14) was used instead of 3 parts of Exemplified Compound (1) as a charge controlling agent. Good copies were obtained as in Example 4.

Example 14 The procedure of Example 4 was repeated, except that 2 parts of Exemplified Compound (15) was used instead of 3 parts of Exemplified Compound (1) as a charge controlling agent. Good copies were obtained as in Example 4.

Example 15 Except that 3 parts of Exemplified Compound (17) was used instead of 3 parts of Exemplified Compound (1) as a charge controlling agent, the procedure was the same as that of Example 4 to obtain Example. Good copies were obtained as in Example 4.

Example 16 The procedure of Example 4 was repeated except that 3 parts of Exemplified Compound (19) was used instead of 3 parts of Exemplified Compound (1) as a charge controlling agent. Good copies were obtained as in Example 4.

Example 17 The procedure of Example 4 was repeated, except that 2 parts of Exemplified Compound (21) was used instead of 3 parts of Exemplified Compound (1) as a charge controlling agent. Good copies were obtained as in Example 4.

Example 18 The procedure of Example 4 was repeated except that 2 parts of Exemplified Compound (22) was used instead of 3 parts of Exemplified Compound (1) as a charge controlling agent. Good copies were obtained as in Example 4.

Example 19 The procedure of Example 4 was repeated except that 4 parts of Exemplified Compound (24) was used instead of 3 parts of Exemplified Compound (1) as a charge controlling agent. Good copies were obtained as in Example 4.

Example 20 The procedure of Example 4 was repeated except that 3 parts of Exemplified Compound (27) was used instead of 3 parts of Exemplified Compound (1) as a charge controlling agent. Good copies were obtained as in Example 4.

Example 21 The procedure of Example 4 was repeated except that 2 parts of Exemplified Compound (28) was used instead of 3 parts of Exemplified Compound (1) as a charge controlling agent. Good copies were obtained as in Example 4.

Example 22 The procedure of Example 4 was repeated except that 3 parts of Exemplified Compound (29) was used instead of 3 parts of Exemplified Compound (1) as a charge controlling agent. Good copies were obtained as in Example 4.

(Example 23) Except that 3 parts of Exemplified Compound (30) was used instead of 3 parts of Exemplified Compound (1) as a charge controlling agent, the procedure was exactly the same as that of Example-4. Good copies were obtained as in Example 4.

(Example 24) Except that 3 parts of the exemplary compound (31) was used instead of 3 parts of the exemplary compound (1) as the charge controlling agent, the procedure was exactly the same as that of Example-4. Good copies were obtained as in Example 4.

Example 25 The procedure of Example 4 was repeated, except that 4 parts of Exemplified Compound (33) was used instead of 3 parts of Exemplified Compound (1) as a charge controlling agent. Good copies were obtained as in Example 4.

(Comparative Example 1) A developer was prepared and subjected to actual copying in the same manner as in Example 4 except that the exemplified compound (1) was not used as a material. Obtained.

(Comparative Example-2 and Example-26) As a comparison, the following compound (IV) was synthesized, and the exemplified compound (3
6) and the charge amount were compared.

[0060]

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The charge amount was measured for a sample prepared as follows. 400 mesh pass sample,
The styrene acrylic having an average particle size of 10 μm was charged at a rate of 1% and mixed with a mixer for 60 seconds. The mixture was 1% mixed with an iron powder carrier having an average particle diameter of 100 μm, stirred with shaking, and then measured for charge amount and a blow-off method. The results are shown below.

[0062]

[Table 9]

From the above results, it was found that Exemplified Compound (36) exhibited better charging characteristics, and the charge amount was 20% higher than Comparative Compound (IV). From this, it is presumed that the exemplary compound (36) can obtain a clearer copy with gradation.

(Comparative Example-3 and Example-27) As a comparison, the following compound (V) was synthesized, and the charge amount was compared with that of the exemplary compound (8).

[0065]

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The sample was prepared in exactly the same manner as in Comparative Example 2 except that a ferrite carrier was used instead of the iron powder carrier. The results of the charge amount are shown below.

[0067]

[Table 10]

From the above results, it is presumed that the comparative compound (V) has a remarkably low charge amount as compared with the exemplary compound (8), so that it is impossible to obtain a clear image without fog.

(Comparative Examples-4 to 10 and Examples-28, 2
9) In the general formula (I), R _{1 to} R ₄ are each as shown in Table 2,

[0070]

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For compounds which are all 1,5-naphthalenedisulfonic acids, the synthesis difficulty, properties, melting point,
Although the results of measurement of thermal stability by DSC are described, the compounds of Comparative Examples -4 to 10 were inferior in any of the above-mentioned properties. Example 28 (Exemplified compound (5), Example 6
Compounds of the present invention similar to those of Comparative Example are shown in Table 2 as Example 29 (Exemplified Compound (7), the same compound as Example 8), but there was no problem with the above performance.

[0072]

[Table 11]

[0073]

[Table 12]

(Comparative Example 11) 1,5-
A toner and a developer were prepared in the same manner as in Example 4, except that 2 parts of naphthalenedisulfonic acid distearyldimethylammonium salt was used. Next, when the actual shooting was performed in the same manner, the chargeability increased with the number of actual shootings, although the initial state was good.
A good copy cannot be obtained.

(Comparative Example 12) 1,5-
Evaluation was performed in the same manner as in Example 4 except that 2 parts of stearyltrimethylammonium naphthalenedisulfonic acid (the same compound as in Comparative Example 8) was used. As a result, the chargeability was increased with the number of actual copies, and a good copy was not obtained. Was.

Comparative Example 13 Evaluation was made in the same manner as in Example 4 except that 2 parts of naphthalene-1-sulfonic acid p-chlorobenzyltributylammonium salt was used as a charge controlling agent. No copy was obtained. Further, even when three parts were used, the charge amount was not improved. On the other hand, when the anion was replaced by 1,5-naphthalenedisulfonic acid ion, a good copy was obtained because of good chargeability and stability of charge amount as shown in Example 8.

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masako Takeuchi 1000 Kamoshita-cho, Midori-ku, Yokohama-shi, Kanagawa Prefecture Inside the Mitsubishi Chemical Research Institute (72) Inventor Hirofumi Oda 370 Enzura, Chigasaki-shi, Kanagawa Prefecture Mitsubishi Chemical Corporation Chigasaki Office (56) References JP-A-4-125655 (JP, A) JP-A-4-269766 (JP, A) JP-A-4-204549 (JP, A) JP-A-4-70849 (JP, A A) JP-A-4-60552 (JP, A) JP-A-6-59518 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G03G 9/08 CA (STN)

Claims (1)

(57) [Claims] 1. An electrostatic image developing toner comprising at least a resin and a colorant, comprising at least one compound represented by the following general formula (I). toner. Embedded image (Wherein, R ₁ represents a substituted or unsubstituted alkyl group having 1 to 24 carbon atoms or a substituted or unsubstituted aralkyl group, and R ₂ , R ₃ and R ₄ each represent a substituted or unsubstituted aralkyl group having 2 to 24 carbon atoms. Represents an unsubstituted alkyl group or a substituted or unsubstituted aralkyl group, and A represents an aromatic ring residue which may have a substituent.)