JP2710342B2 - Toner for developing electrostatic images - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a toner for developing an electrostatic image.

[Prior Art] In a two-component developer, a charge control agent (hereinafter referred to as CCA) is added to control the charge amount. But CCA
However, there is a drawback that environmental fluctuations are large, such as high charge under low temperature and low humidity, and low charge under high temperature and high humidity.

[Purpose] It is an object of the present invention to provide a toner for developing an electrostatic charge image that can always obtain a stable charge without being affected by environmental fluctuations.

[Constitution] In the present invention, the electrostatic image developer is a toner composed of a binder resin and a colorant, both an organic acid metal salt or an organic acid metal complex as a negative CCA and a quaternary aluminum salt as a positive CCA. Is contained.

In other words, in an environment where charging is high, the charging level is lowered by the reverse polarity CCA, and in an environment where charging is low, the polarity is reversed.
Since the charging ability of the CCA also decreases, the charging level does not decrease, and the charge amount of the toner is stabilized.

The amount of CCA added to the toner in the present invention is 100% of the binder resin.
0.5 to 20 parts by weight of main CCA, 0.01 to 10 parts by weight of sub-CCA (more preferably 1 to 10 parts by weight of main CCA, 0.05 to 2 parts by weight of sub-CCA)
0 parts by weight, and the ratio of primary CCA: sub CCA is 5: 1 or more).

The primary CCA and the secondary CCA are determined depending on whether the polarity of the toner is positive or negative. That is, when it is desired to make the polarity of the toner negative, the organic acid metal salt or organic acid metal complex as the negative CCA becomes the main CCA, and the quaternary ammonium salt as the positive CCA becomes the sub CCA. When the polarity of the toner is desired to be positive, the main and sub CCAs are reversed.

Examples of the quaternary ammonium salt of positive polarity CCA in the CCA used in the present invention include those having the following structural formulas.

Wherein R ₁ is an alkyl group containing about 12 to about 22 carbon atoms, preferably about 14 to 18 carbon atoms, and R ₂ and R ₃ are about 1 to about 5 Are each independently selected from alkyl groups containing carbon atoms of
R ₄ is an alkylene group containing from about 1 to about 5 carbon atoms, R ₅ is a tolyl group or an alkyl or substituted alkyl group containing from about 1 to about 3 carbon atoms,
And n is a number of 3 or 4. Examples of alkyl groups include methyl, ethyl, propyl, butyl, pentyl, hexyl, octyl, nonyl,
Includes decyl, myristyl, cetyl, olely, pentadecyl, heptadecyl, stearyl and the like. R ₁
Preferred alkyl groups contain myristyl, stearyl, and cetyl for, preferred alkyl groups for R _2, R ₃ and R ₅ contains a methyl, ethyl and propyl, preferably an alkylene group for R ₄ is Methylene and ethylene. Examples of other alkylene groups include propylene, butylene, pentylene, and the like.

Specific examples of the formula (1) include, for example, stearyldimethylbenzylammonium P-toluenesulfonate, stearyldimethylbenzylammonium methylsulfate, stearyldimethylphenethylammonium methylsulfate, stearyldimethylphenethylammonium p-toluenesulfonate, cetyldiethylbenzylammoniummethyl Sulfate, myristyldimethylphenethylammonium p-toluenesulfonate, cetyldimethylbenzylammonium methylsulfate, and the like.

Wherein n is a number from about 5 to about 2500, and R ₁ , R ₂ and
R ₃ is independently selected from an alkyl group, and X is a halogen). Can be mentioned.

Wherein each of R ¹ , R ² , R ³ and R ⁴ is 10 carbon atoms
The following aromatic or aliphatic hydrocarbons. each
R ¹ , R ² , R ³ and R ⁴ can be linear or branched aliphatic or aromatic hydrocarbon moieties, which include allyl and alkyl moieties such as methyl, ethyl, propyl, butyl, Includes ventil, hexyl, futyl, isopropyl, phenyl and the like.

Specific examples of X represent anions such as halogen, phosphate, acetate, nitrate, benzoate, methyl sulfate, perchlorate, tetrafluoroborate and benzenesulfonate, and halogen is particularly preferable.

Examples of formula (4) include, for example, distearyl dimethyl ammonium chloride, dicetyl dimethyl ammonium chloride, dicetyl methyl benzyl ammonium bromide, stearyl cetyl dimethyl ammonium chloride, dimyristyl dimethyl ammonium iodide, decyl trimethyl ammonium hydroxide, hexadecyl Penzyl dimethyl ammonium hydroxide, penzyl phenyl dimethyl ammonium hydroxide and the like.

Further, as the organic acid metal salt and organic acid metal complex of negative polarity CCA, salicylic acid Zn salt, salicylic acid Cr salt, salicylic acid
Salicylic acid metal salts such as Al salt, tert-butyl salicylic acid Zn salt, tert-butyl salicylic acid Cr salt, and tert-butyl salicylic acid Al salt; organic acids such as α-naphthoic acid Zn complex, α-naphthoic acid Cr complex, and α-naphthoic acid Al complex There are metal complexes and the like.

As the colorant used in the present invention, a conventionally known face wash may be used alone or in combination. Other examples include carbon black, lamp black, nigrosine dye, aniline blue, phthalocyanine green, Hansa Yellow G, rhodamine 6G, lake, calco oil blue, ultramarine blue, Dupont oil red, and malachite green occite. The amount of colorant added is 10 for binder resin.
It is in the range of 1 to 25 parts by weight with respect to 0 parts by weight. (Preferably 2 to 10 parts by weight) As the binder resin used in the present invention, polystyrene,
Styrene such as polyvinyl toluene and its substituted homopolymer, styrene-propylene copolymer, styrene-
Styrenes such as vinyl naphthalene copolymer, styrene-ethyl acrylate copolymer, styrene-acrylonitrile copolymer, styrene-vinyl methyl ether copolymer, styrene-vinyl methyl ketone copolymer, and styrene-butadiene copolymer Copolymer, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, silicone resin, polyester, polyurethane, polyamide, epoxy resin, polyvinyl butyral, rosin, modified rosin, terpene resin, phenol resin, xylene resin, aliphatic or alicyclic Aromatic hydrocarbon resins, aromatic petroleum resins and the like are used alone or as a mixture.

The toner of the present invention is manufactured by a known method. For example, binder resin, colorant, CCA, etc. are premixed with a Henschel mixer, a super mixer, etc., then melted and kneaded with a kneading machine such as a three roll, kneader, solidified by cooling, pulverized with a jet mill, The product is classified by a classifier.

Hereinafter, the present invention will be described in more detail with reference to Examples.

Example 1 Composition of Toner Styrene / Acrylonitrile (80/20) Copolymer 100 parts by weight Carbon black 10 parts by weight Negative charge control agent (Bontron E-84, manufactured by Salicylic Acid Zn Salt Orient Chemical Co., Ltd.) 5 parts by weight Positive charge Control agent (quaternary ammonium salt, Hodogaya Chemical, TP-302)
0.5 parts by weight After thoroughly mixing the above ingredients with a Henschel mixer,
The mixture was kneaded with a three-roll mill heated to about 140 ° C. The kneaded product was allowed to cool naturally, then coarsely pulverized by a rotoplex, pulverized using a fine pulverizer using a jet stream, and further classified by a zigzag classifier to obtain a toner having an average particle diameter of 10 μm.

Place the toner and silicon-coated carrier weighed so that the toner concentration is 2.5% in separate containers, and adjust the temperature and humidity.
After leaving it in the air at 20 ° C and 50% for 3 hours, put it in a roll mill,
Mix for 10 minutes to make a developer. When the amount of triboelectric charge of the toner with respect to the carrier was measured by the blow-off method, it was -27 μm.
c / g.

Also, after leaving the above toner and silicon-coated ferrite carrier in the atmosphere set at a temperature and humidity of 10 ° C./5% and 30 ° C. 90% for 3 hours, respectively, put them in a roll mill and mix them for 10 minutes. When the triboelectric charge was measured by the blow-off method, the triboelectric charge at each temperature and humidity was as follows.

Temperature / humidity Amount of triboelectric charge of toner after mixing for 10 minutes (μc / g) 10 ° C 15% −31 20 ° C 50% −27 30 ° C 90% −24 Of the above triboelectric charge, temperature and humidity are 10 ° C 15% The environmental change rate was calculated and obtained using the measured value of the above and the measured value at 30 ° C. and 90%.

The environmental change rate obtained by the above equation is 22.6%, indicating that the toner of the present invention is very stable against environmental changes such as temperature and humidity.

Example 2 Composition of Toner Styrene / acrylonitrile (70/30) copolymer 100 parts by weight Carbon black 10 parts by weight Negative charge control agent (Bontron E-84, manufactured by Orient Chemical Co.) 0.3 part by weight Positive charge control agent ( 6 parts by weight of Bontron P-51 manufactured by Orient Chemical Co., Ltd. The above materials were produced according to the production method shown in Example 1. The results of measuring the triboelectric charging property of this toner with respect to the carrier of Example 1 at each temperature and humidity at a toner concentration of 2.5% are as follows.

Temperature and humidity Amount of triboelectric charge of toner after mixing for 10 minutes (μc / g) 10 ° C 15% +32 20 ° C 50% +29 30 ° C 90% +27 Stable against changes in temperature and humidity.

Comparative Example As a comparative example of the present invention, a toner containing no positive CCA was prepared.

Toner composition Styrene / acrylonitrile (80/20) 100 parts by weight Carbon black 10 parts by weight Negative charge control agent (manufactured by Orient Chemical Co., Ltd., Bontron E-84) 5 parts by weight The above materials were produced according to the production method described in Example 1. did.

As a result of measuring the triboelectric charging property of this toner with respect to the carrier of Example 1 under each temperature and humidity at a toner concentration of 2.5 wt%,
It was as follows.

Temperature / humidity Amount of triboelectric charge after mixing for 10 minutes (μc / g) 10 ° C 15% −37 20 ° C 50% −22 30 ° C 90% −6 The environmental fluctuation rate of the above toner is 83.8%. On the contrary, it was unstable.

[Effects] According to the present invention, there is no large variation in the triboelectric charge amount of the toner due to the previously insufficient change in temperature and humidity, and toner scattering and fogging in a high temperature and humidity environment are prevented. The reliability of information processing terminal devices such as various printers and facsimile machines using the method can be improved.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Chiharu Mochizuki 1-3-6 Nakamagome, Ota-ku, Tokyo Ricoh Co., Ltd. (56) References JP-A-63-68848 (JP, A) JP-A-Hei 1-155361 (JP, A) JP-A-57-196264 (JP, A) JP-A-59-232360 (JP, A) JP-A-61-118761 (JP, A)

Claims (1)

(57) [Claims] 1. A developer for developing an electrostatic image, wherein a toner comprising a binder resin and a colorant contains an organic acid metal salt or an organic acid metal complex and a quaternary ammonium salt. Image developing toner.