JPS6373269A - Color toner for electrophotography - Google Patents

Abstract

PURPOSE:To obtain the titled toner having stabilized electric charge and capable of preventing greasing by incorporating a metallic salt of fatty acid having >=16 carbon atom in a negative charge toner which contains a polyester resin composed of a bisphenol type diol and a polyvalent carboxylic acid as a binder. CONSTITUTION:The metallic salt of the fatty acid having >=16 carbon atom is incorporated in the negative charge toner which contains the polyester resin composed of the bisphenol type diol and the polyvalent carboxylic acid as the binder and an oil-soluble dye and/or pigment. The amount of polyester is preferably >=70wt% on the total weight basis of the binder resin. The used amount of the metallic salt of fatty acid having >=16 carbon atom added to the toner is preferably 0.1-0.5pts.wt. on the 100pts.wt. binding resin. As the metallic salt of fatty acid; zinc-, cadimium-, or barium-stearate, dibasic lead- stearate, zinc-, magnesium-, or iron-oleate, etc., are exemplified. Thus, the titled toner capable of obtaining a clear image and having stabilized electric charge and less greasing is obtd.

Description

[Detailed Description of the Invention] The present invention relates to a color toner for dry electrophotography, and more particularly to a toner that can obtain stable chargeability in a two-component developer consisting of a toner and a carrier. be.

It is well known that a polyester resin synthesized from a bisphenol diol and a polyhydric carboxylic acid is used as a toner binder in order to control the toner to be negatively charged.

However, with toners in which polyester resin is used as a toner binder and dyes and pigments are dispersed therein as colorants, charging properties tend to become unstable during operation due to the selection of colorants and differences in dispersibility. occurs, resulting in a smeared image.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a color toner for electrophotography which eliminates the drawbacks of the conventional toner, has stable charging properties, and is capable of producing images without background smudge.

As a result of intensive research to achieve the above object, the present inventors have developed a two-component developer consisting of toner and carrier,
The above object is achieved by providing a negative polarity toner containing a polyester resin comprising a bisphenol diol and a polycarboxylic acid as a binder, which contains a fatty acid metal salt having 16 or more carbon atoms. I found out what I can achieve.

That is, the present invention is characterized in that a negative polarity toner containing a polyester resin made of bisphenol diol and a polyhydric carboxylic acid as a binder and containing an oil-soluble dye and pigment contains a fatty acid metal salt having 16 or more carbon atoms. It is in.

As the polyester resin used as a main component in the binder resin of the toner of the present invention, thermoplastic saturated or unsaturated polyesters obtained by condensation of bisphenyl diols and polyhydric carboxylic acids are widely used. Representative diols are shown below.

(1) Polyoxypropylene (2,2)-2,2-bis(4-hydroxyphenyl)propane, (2) Polyoxyethylene (2)-2,2-bis(4-hydroxyphenyl)propane.

(3) Polyoxystyrene (6)-2,2-bis(4-
hydroxyphenyl)propane, (4) polyhydroxybutylene (2)-2,2-bis(4-hydroxyphenyl)propane, (5) polyoxypropylene (3)-bis(4-hydroxyphenyl)thioether, (6) Polyoxypropylene (2)-2,2-bis(4
-cyclohexanol)propane, (7) polyoxyethylene (2)-2,6-dichloro-4-hydroxyphenyl, (8) polyoxyethylene (2+ 5)-P+ p-bisphenol, (9) polyoxybutylene ( 4) Bis(4-hydroxyphenyl)ketone.

(10) polyoxyethylene-2,2-bis(4-hydroxyphenyl)propane, and (11) polyoxypropylene-2,2-bis(4-hydroxyphenyl)propane.

Examples of polyhydric carboxylic acids include maleic acid, fumaric acid, glutaric acid, phthalic acid, maleic anhydride, fumaric anhydride, phthalic anhydride, isophthalic acid, terephthalic acid, trimellitic acid, 1°2.4 -benzenetricarboxylic acid, etc.

Examples of polyester resins using these diols and polyhydric carboxylic acids include:

The ratio of these polyesters to the total binder resin is
It is 50% or more, preferably 70% or more.

As other binder resins that can be used in combination with polyester resins, there are the following conventionally known binder resins.

Monopolymers of styrene and its substituted products such as polystyrene, poly-P-chlorostyrene, polyvinyltoluene, styrene-P-chlorostyrene copolymers, styrene-propylene copolymers, styrene-vinyltoluene copolymers, styrene-vinyl Naphthalene copolymer, styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-methyl methacrylate copolymer , styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer,
Styrene-α-methyl chloromethacrylate copolymer,
Styrene-acrylonitrile copolymer, styrene-vinyl methyl ether copolymer, styrene-vinylethyl ether copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene- Styrenic copolymers such as acrylonitrile-indene copolymers, polyvinyl chloride,
Polyvinyl acetate, polyethylene, polypropylene, silicone resin, polyester.

Polyurethane, polyamide, epoxy resin, polyvinyl butyral, rosin, modified rosin, terpene resin, phenolic resin, xylene resin.

Aliphatic or alicyclic hydrocarbon resins, aromatic petroleum resins, chlorinated paraffins, paraffin waxes, etc. may be used alone or in combination.

The amount of the fatty acid metal salt having 16 or more carbon atoms added to the toner is 0.05 to 1.0 parts by weight per 100 parts by weight of the binder resin.
0 parts by weight, preferably 0.1 to 0.5 parts by weight.

Specific examples of these fatty metal salts include metal stearates with metals such as zinc, cadmium, barium, lead, iron, nickel, cobalt, copper, aluminum, and magnesium; dibasic lead stearate; zinc, magnesium,
Oleate metal salts with metals such as iron, cobalt, copper, lead, calcium, etc. Palmitate metal salts with nialium, calcium, etc.; lead caprylate; lead caproate; zinc linoleate; cobalt linoleate; calcium ricinoleate; zinc; There are lysyl inate metal salts with cadmium, etc.

Various colorants can be used in the toner of the present invention. For example, yellow colorants include nitro pigments such as Naphthol Yellow S, Hansa Yellow 5G,
Examples include azo pigments such as Hansa Yellow 3G, Hansa Yellow G, Benzidine Yellow GR, Benzidine Yellow G, and Vulcan Fast Iniro-5G, and inorganic pigments such as yellow iron oxide and loess. In addition, as dyes, C, 1. listed in the color index are used. Solvent Yellow 2, C,1, Solvent Yellow 6, C,1, Solvent Yellow 14, C,1, Solvent Yellow 15,
These are oil-soluble dyes such as C,1, Solvent Yellow 16, C,1, Solvent Yellow 19, and C,1, Solvent Yellow 21.

The magenta colorant includes pigments such as quinacridone pigments such as C,1, Pigment 122 and C,1, Pigment Violet 19, rhodamine pigments such as Rhodamine 6G Lake, Rhodamine B Lake, and C,1, Pigment Red 81; C,1, Pigment Red 87, C,1,
Violet 1, C, 1, Pigment Violet 38
Thioindigo pigments such as Brilliant Carmino 6B,
Examples include azo pigments such as Lysol Rubine GK, and oil-soluble dyes such as C,1, Solvent Red 49, C,1, Solvent Red 19, and C,1, Solvent Red 52.

The cyan colorant includes phthalocyanine blue, heliogen blue G, first sky blue, C,
, 1, Pigment Blue 15, C, I.

Pigment Blue 16, C, 1, Pigment Blue 17
°C,1, Pigment Green 7, C,1, Pigment Green 12, C,1, Pigment Green 36. C
, L Pigment Green 37, C,1, Pigment Green 38, etc.;
.

Solvent Blue 25, C, 1, Solvent Blue 55
, C,1, Solvent Blue 0, C,1, Solvent Blue 40, C,1, Direct Blue 25. C,1
, Direct Blue 86 and other oil-soluble dyes.

Modified versions of the above dyes and pigments can also be used.

It is also possible to use a blend of two or more.

The amount of the above-mentioned coloring agent added to the toner component may be as long as the toner is sufficiently colored.
．． It is 1 to 30 parts by weight.

Particularly in the case of color toners, the preferred ratio of these colorants and binder resins is by weight.

Yellow; 6: 100-10: 100 magenta; 5: 100-10: 100 cyan; 3
: 100 to 8: 100.

The present invention will now be explained in more detail with reference to the following examples, but it should be understood that the present invention is not limited thereto.

Example 1 Polyoxypropylene (2,2)-2,2-bis(4-
An average particle size of 10.5 μm containing 5 parts by weight of C, 1, Pigment Red 81 based on 100 parts by weight of a polyester resin consisting of (hydroxyphenyl) propane and fumaric acid.
To the toner particle powder, 1.0 part of hydrophobic silica was externally added, and further 0.3 part by weight of zinc stearate was externally added to prepare a toner.

The obtained toner was mixed so that the toner concentration was 3% by weight.
A developer was made using amorphous iron powder with an average particle size of 100 μm.

Using this developer, the dry two-component electronic copying machine Recopy FT
When copying was performed using the 5510, clear images with no background stains were obtained. When 30,000 sheets were continuously copied, the initial charge amount was -28.4it c/g.
When the toner concentration was 3.0%, the charge amount was extremely stable at -27.8 μc/g and the toner concentration was 2.7% when 30,000 sheets were printed. Furthermore, the obtained images were clear and free of background stains.

Furthermore, when the same developer was used to produce a full-color image using a dry-type full-color electronic copying machine Ricoh Color 5000,
Clear images with no background stains were obtained.

Example 2 2 parts by weight of C,1, Pigment Red 81 and 2 parts by weight of C,1, Pigment Red 57 to 100 parts by weight of a polyester resin consisting of polyoxypropylene (3)-bis(4-hydroxyphenyl)thioether and isophthalic acid. 1
A toner is prepared in the same manner as in Example 1, using the weight part as the colorant.

To this, 0.3 parts by weight of zinc stearate was externally added to prepare a toner.

The obtained toner was used as a developer in the same manner as in Example 1, and when copying was carried out using a Recopy FT5510, a clear image without background smudge was obtained. The amount of charge remained stable even after 30,000 sheets were continuously copied.

Example 3 Polyoxypropylene (2,2)-2,2-bis(4-
An average particle size of 12.5 μm containing 5 parts by weight of C,1, Pigment Blue 25 based on 100 parts by weight of a polyester resin consisting of (hydroxyphenyl) propane and fumaric acid.
To the toner particle powder, 1.0 part of hydrophobic silica was externally added, and further 0.3 part by weight of zinc stearate was externally added to prepare a toner.

The obtained toner was mixed so that the toner concentration was 5% by weight.
A developer was made using amorphous iron powder with an average particle size of 100 μm.

Using this developer, the dry two-component electronic copying machine Recopy FT
When copying was performed using the 5510, clear images with no background stains were obtained. Furthermore, when 30,000 sheets were continuously copied, the initial charge amount was -24.5 μc/g, and the toner concentration was 5.0%, but after 30,000 sheets, the charge amount was -24.5 μc/g.
The toner concentration was extremely stable at 22.3 μc/g and 4.8%. Furthermore, the obtained images were clear and free of background stains.

Furthermore, when the same developer was used to produce a full-color image using a dry-type full-color electronic copying machine Ricoh Color 5000,
Clear images with no background stains were obtained.

Example 4 3 parts by weight of C,1, Pigment Blue 17, C,1, Solvent Blue 25 to 100 parts by weight of a polyester resin consisting of polyoxypropylene (3)-bis(4-hydroxyphenyl)thioether and isophthalic acid. 2
A toner is prepared in the same manner as in Example 1, using the weight part as the colorant.

To this, 0.3 parts by weight of zinc stearate was externally added to prepare a toner.

The obtained toner was used as a developer in the same manner as in Example 3, and when copying was carried out using a Recopy FT5510, a clear image without background smudge was obtained. The amount of charge remained stable even after 30,000 sheets were continuously copied.

Comparative Example 1 C,1 was added to 100 parts by weight of the same polyester resin as in Example 1.
, hydrophobic silica, 1.
0 part was added externally to form a toner.

The obtained toner was mixed so that the toner concentration was 3% by weight.
A developer was made using amorphous iron powder with an average particle size of 100 μm.

Using this developer, the dry two-component electronic copying machine Recopy FT
When I made a copy using the 5510, the image had noticeable background stains. When 30,000 sheets were continuously copied, the initial charge amount was -27.5 μc/g and the toner density was 2.
．． Compared to 9%, at 30,000 sheets, the amount of charge is -12.2
It exhibited unstable charging characteristics with μc/g and toner concentration of 2.6%. The obtained image had background stains and lacked sharpness.

Comparative Example 2 C, 1 was added to 100 parts by weight of the same polynystyl resin as in Example 3.
, hydrophobic silica, 1.
0 part was added externally to form a toner.

The obtained toner was mixed so that the toner concentration was 5% by weight.
A developer was made using amorphous iron powder with an average particle size of 100 μm.

Using this developer, the dry two-component electronic copying machine Recopy FT
When I made a copy using the 5510, the image had noticeable background stains. When 30,000 sheets were continuously copied, the initial charge amount was -22.1 μC/g and the toner density was 4.
．． Compared to 9%, at 30,000 sheets, the amount of charge is -10.6
It showed unstable charging characteristics with μc/g and toner concentration of 4.6%. The obtained image had some background stains and lacked sharpness.

Twisting - End As described above, the toner to which fatty acid metal salts are added according to the present invention has stable charging properties and can provide clear images without background smudges.

Patent Roganjin Ricoke Co., Ltd.

Gi Agent: Patent attorney: Tsukimura Tsukimura, 1 Shigegai Tsumeso

Claims (1)

[Claims] 1. A two-component developer consisting of a toner and a carrier, a negative polarity toner whose binder is a polyester resin consisting of a bisphenol diol and a polyhydric carboxylic acid, characterized by containing a fatty acid metal salt having 16 or more carbon atoms. Color toner for electrophotography.