JPS6040020B2 - Positively charged cyan toner for electrophotography - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a positively charged toner for electrophotography for developing a negative electrostatic latent image in electrophotography and the like.

There are various methods for electrophotography, but in general, a uniform electrostatic charge is applied to a photoconductive insulating layer, and an electrostatic latent image is formed by irradiating the insulating layer with a light image. The powder image is visualized using a dry toner whose main component is a resin that is charged by friction with a carrier such as iron powder or glass bulbs, and then the powder image is transferred to paper, etc., and then fixed by heat, pressure, or solvent vapor. It is something to do.

In color electrophotography, the original is exposed using color separation filters (blue, green, and red), and each of the above steps is repeated multiple times using yellow, magenta, and cyan color toners to produce a color image. It's something you get.

Conventionally, there are polystyrene resins, epoxy resins, phenolic resins, etc. as resins used in cyan toners that are positively charged due to friction with the carrier. Since it exhibits a weak negative charge, in order to use it as a positively charged toner, it has generally been done to use a resin or colorant with a strong positive charge control effect.

However, there are very few of them, and even if there are, each has its own drawbacks.

For example, a primary amino group (-N
H2), a secondary amino group (1NHR), a tertiary amino group (NR, R2), a pyridinium group, etc. are introduced into the resin.
There are drawbacks such as generation of an unpleasant odor due to the functional group during heat fixing and a decrease in charge control effect in a high-temperature environment.

In addition, colorants such as phthalocyanine blue pigments (
C. 174160 74100), etc., had the disadvantage that the effect could not be obtained unless a large amount was used. therefore,
In any case, the resins and colorants that can be selected to create a toner with clear positive polarity are severely limited, and the characteristics necessary for a dry cyan toner, such as color tone, transparency, light fastness, and fixing properties, are severely limited. Considering storage stability, fluidity, etc., there are almost no resins or colorants that can be used.

The present invention relates to a positively charged cyan toner for dry electrophotography, which uses a compound with a strong charge control effect, exhibits sufficient positive polarity even in a small amount, and is not limited by the type of resin used.

That is, the present invention provides a dry electrophotographic toner comprising a phthalocyanine pigment and a resin having the following general formula: R, R3: day or CH3, C2 day 5 R2, R4: CH3 or C2 day 5 R5, R6: This is a positively charged cyan toner for electrophotography, which is characterized by containing a compound represented by anion or CH3R7: day or CI Ae: anion.

Examples of compounds that fall into the above general formula include the following.

(Product name: NZEN MarisicCyanine, made by Hodogaya Chemical Industry ■) (Product name: Prim Hibi Nihi BXc
onc. Manufactured by Sumitomo Chemical Co., Ltd.) (Product name: YamaZENDia)
mondGreenGH (manufactured by Hoya Kagaku Kogyo Co., Ltd.)) These are just examples, and of course other compounds that fall into the above general formula can be applied to the present invention.

The content of such a compound in the toner is 1% by weight or less, preferably 5% or less based on the amount of resin.

In addition, this compound has extremely low light resistance, so it is difficult to use it alone as a coloring agent for toners, so it is better to use phthalocyanine pigments as a coloring agent to obtain the color tone of cyan toner. It has extremely strong light resistance, transparency, and color tone. therefore,
The main purpose of the compound represented by the above single-pronged formula is to be used as a positive charge control agent. There is no problem with the image (cyan color) even if the color of the charge control agent of the present compound is thigh color.

Regarding storage stability, since toners and developers are generally stored in a bolt, the present compound will not undergo chemical changes due to light during storage, and the charge control effect will not deteriorate. As the resin in the present invention, any resin used in ordinary dry toners can be used, but in general,
The selection may be made in consideration of properties for dry cyan toner other than charge control properties, such as coloration, transparency, adhesiveness, fluidity, and pulverizability of the resin itself.

For example, styrene resins, epixy resins, phenol resins, etc. are used, but styrene resins provide particularly preferable positive chargeability when used in combination with the above compounds. The toner of the present invention is particularly effective for use in the three primary colors of electrophotographic color copying machines.

Next, examples and test results will be shown.

Example 1 Polystyrene (trade name: Picolastik D-125 manufactured by Esso Standard Oil ■) 10 parts by weight Phthalocyanine (trade name: Lionol Flu KL manufactured by Toyo Ink Manufacturing ■) 5 parts by weight NZENBasicCya
nine days (manufactured by Hoya Chemical Industry)
3 parts by weight or more is melted and kneaded in a roll mill, cooled and coarsely ground using a jet mill, and then finely ground using an air jet type pulverizer.

The obtained characteristic powder is classified to obtain particles of 5 to 2 tsubo and used as toner.
And so. Carrier iron powder (E
A developer was prepared by mixing 97 parts by weight of FV150-250 mesh (manufactured by Nippon Tetsuko Co., Ltd.).

When this developer was used for development using a plain paper copying machine using a commercially available zinc oxide photoreceptor, a clear positive cyan image without fog was obtained.

The charge amount of the toner was measured using a commercially available blow-off powder charge measuring device and was found to be +5.2 m/c'. Example 2 Styrene-acrylic acid copolymer (product name: Heimer SB
M73 (manufactured by Sanyo Chemical) 10 parts by weight Phthalocyanine Flue (product name: Lionor Flu KL manufactured by Toyo Ink Manufacturing) 5 parts by weight Primoc
ineBXconc. (manufactured by Sumitomo Chemical Co., Ltd.) 4 parts by weight or more were mixed in the same manner as in Example 1 to prepare a toner.

Using this toner, a test was conducted in the same manner as in Example 1, and a clear positive cyan image without fogging was obtained. The amount of charge on the toner is 16. It was autumn/evening. Example 3 Styresoacrylic acid copolymer (trade name: /・Imer S
BM73 (manufactured by Sanyo Chemical) 10 parts by weight Phthalocyanine Fluoride (Product name: Phthalocyanine Fluorine L)
BG manufactured by Sumitomo Chemical Co., Ltd.) 5 parts by weight MZENDi
amondGreenGH (manufactured by Hodogaya Chemical Co., Ltd.)
2 parts by weight or more were mixed in the same manner as in Example 1 to prepare a toner.

When this toner was tested in the same manner as in Example 1, a clear positive cyan image without fogging was obtained.

Claims (1)

[Claims] 1. A cyan toner for dry electrophotography consisting of a phthalocyanine pigment and a resin, which has a general formula ▲ mathematical formula, chemical formula, table, etc. ▼ However, R_1, R_3: H or CH_3, C_2H_5R_
2, R_4: CH_3 or C_2H_5R_5, R_
6:H or CH_3R_7:H or Cl A■: A positively charged cyan toner for electrophotography, characterized by containing a compound represented by anion.