JP2796127B2 - Dry electrophotographic toner - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a dry electrophotographic toner.

[Prior art] In dry electrophotography, an electrostatic latent image is formed on a photoreceptor by a conventional method, developed with dry toner, the toner image is transferred onto copy paper, and then heat-fixed (usually using a heat roller). And have a copy. The dry toner used in this method has a binder resin and a colorant as main components, as is well known,
If necessary, additives such as a charge control agent and an anti-offset agent are added. Here, as binder resins, polystyrene, styrene and the like are required in terms of properties required for toner, namely, transparency, insulation, water resistance, fluidity (as a powder), mechanical strength, gloss, thermoplasticity, pulverizability, and the like. -Acrylic copolymers, polyester resins, epoxy resins and the like are generally used, and among them, styrene resins are widely used because of their excellent crushability, water resistance and fluidity. However, in order to preserve the copy obtained with the styrene-based resin-containing toner, if it is placed in a document holder made of a vinyl chloride-based resin sheet, the image side of the copy is left in close contact with the sheet. The plasticizer contained in the vinyl chloride resin undergoes transfer plasticization to the fixed toner image and is fused to the sheet side. As a result, when the copy is separated from the sheet, the toner image is partially or entirely peeled off from the copy, and Also had the disadvantage that it was also soiled. Such defects are also observed in the polyester resin-containing toner.

As measures for preventing transfer to a vinyl chloride resin sheet as described above, JP-A-60-263951 and JP-A-61-240252 disclose an epoxy resin that is not plasticized with a plasticizer for a vinyl chloride resin to a styrene resin or a polyester resin. Proposals have been made to blend.

However, when such a blended resin is used particularly for a color toner, the offset property, the curl of the fixed image, and the glossiness (the colorless image may be poor if the glossiness is low, due to the incompatibility between different resins). Visible), coloring, transparency and coloring.

Therefore, an epoxy resin toner mainly composed of an epoxy resin is considered. Various toners have been devised heretofore, but conventionally known epoxy resins do not always have sufficient properties such as offset properties, curl of a fixed image, and glossiness. Also, charging stability of the epoxy resin becomes a problem.

Generally, a toner is composed of a binder resin, a colorant, a charge control agent, and the like. Various types of face wash are known as colorants, some of which have charge control properties, and some of which have two functions of a colorant and a charge control agent.

It has been widely practiced to use an epoxy resin as a binder resin to form a toner with the above-described composition, but the problem is the dispersibility of a face wash, a charge control agent, and the like.

Generally, the kneading of the binder resin, the face wash, the charge control agent and the like is performed by a hot roll mill, and it is necessary to uniformly disperse the face wash, the charge control agent and the like in the binder resin. But,
It is difficult to sufficiently disperse the pigment, and if the facial cleanser as a coloring agent is poorly dispersed, the coloring is poor and the degree of coloring is low. In addition, if the dispersion of the charge control agent or the like is poor, the charge distribution becomes non-uniform, and poor charging, background contamination, scattering, insufficient ID, blurring,
It causes various failures such as poor cleaning.

JP-A-52-86334 discloses a compound having a positive charge property by reacting an aliphatic primary or secondary amine with a terminal epoxy group of a ready-made epoxy resin. In the above reaction, the amount of amine to be reacted is limited, and it is difficult to set an arbitrary charge level. In addition, since a long-chain amine is introduced at both ends, charging is unstable and does not contribute to dispersibility of a face wash or the like.

[Problem to be Solved by the Invention] A first object of the present invention is to provide a dry electrophotographic toner having excellent color reproducibility.

A second object of the present invention is to provide a dry electrophotographic toner having a stable positive charging property.

A third object of the present invention is to provide a toner having good compatibility with other resins and a good dispersion of a face wash or the like.

A fourth object of the present invention is to provide a dry electrophotographic toner which does not transfer a toner image to a sheet even when a fixed image surface of a copy is brought into close contact with a vinyl chloride resin sheet.

A fifth object of the present invention is to provide a dry electrophotographic toner having excellent fixing properties and good pulverizability.

[Means for Solving the Problems] The toner of the present invention is a dry electrophotographic toner containing a colorant and a binder resin as main components, wherein the binder resin is obtained by introducing a primary amine into a main chain of an epoxy resin. Amine-modified epoxy resin, a mixed resin of a polyester resin or a styrene-acrylic copolymer comprising a bisphenol-type diol and a polycarboxylic acid, wherein the amine-modified epoxy resin is 95 to 60 parts by weight, The resin or the styrene-acrylic copolymer is 5 to 40 parts by weight.

As a result of various studies, the present inventors have made an amine-modified epoxy resin in which a primary amine has been introduced into the main chain of the epoxy resin, and have found that the above object can be achieved by using this as a binder resin.

In general, amine can be introduced by adding a primary amine to a bisphenol A type epoxy resin. At this time, bisphenol A can also coexist. However, it is preferable that the amine portion is uniformly dispersed in the resin molecule. It is good for the purpose, and therefore, a lower amine bisphenol A type epoxy resin has a primary amine, bisphenol A
Is preferably polymerized to form a high molecular weight product.

Specific examples of the primary amine used in the present invention include methylamine, ethylamine, propylamine, isopropylamine, butylamine, amylamine, hexylamine, heptylamine, octylamine, nonylamine, decylamine, undecylamine, dodecylamine and triamine. Decylamine, tetradecylamine, pentadecylamine, cetylamine, cyclohexylamine, laurylamine, stearylamine and the like.

These amines to be introduced have a long-chain alkyl group and form a comb structure, so that the dispersibility of the face wash is improved,
In addition, compatibility with other resins is also improved.

On the other hand, examples of the liquid epoxy resin include EPOMIC R140, EPOMIC R140P, EPOMIC R139, and EPOMIC # 828 (all manufactured by Mitsui Petrochemical Industry Co., Ltd.). , Bisphenol S.

By introducing an amine, the epoxy resin of the present invention exhibits positive charge. Unlike the charging performance of a charge control agent or the like, the resin itself exhibits positive charging, so that charging is extremely stable and has sufficient durability. It is also possible to arbitrarily set the charging level depending on the amount of introduction. The amount of the introduced amine is 0.01 to 1.00% by weight based on 100 parts by weight of the epoxy resin.

A typical example of the epoxy resin used in the present invention is a polycondensate of bisphenol A and epichlorohydrin. Commercial products of such epoxy resins include EPOMIC R301, EPOMIC R302, EPOMIC R304, EPOMIC
R304P, EPOMIC R307, EPOMIC R309, EPOMIC R
362, EPOMIC R363, EPOMIC R364, EPOMIC R36
5, Epomic R366 and Epomic R367 (all manufactured by Mitsui Petrochemical Industries, Ltd.).

Further, there is an epoxy resin having an arbitrary softening point obtained by a polyaddition reaction between a liquid epoxy resin and a bisphenol. Epoxy R1 is a commercially available liquid epoxy resin.
40, EPOMIC R139, EPOMIC R140P (all manufactured by Mitsui Petrochemical Industry Co., Ltd.), and bisphenols include bisphenol A, bisphenol F, bisphenol AD and the like.

Furthermore, the present inventors have conducted various studies on the amine-modified epoxy resin according to the present invention without deteriorating its basic properties, and to obtain better fixing properties. A mixed system with a polyester resin comprising a polyvalent carboxylic acid or a styrene-acrylic copolymer has been found. As a result, it was found that the offset resistance was further improved, and the pulverizability during the production of the toner was also improved. Compatibility is a problem because two different resins are blended, but by defining the mixing ratio, the offset resistance can be improved without substantially impairing the basic characteristics of the amine-modified epoxy resin. be able to.

That is, the amine-modified epoxy resin of the present invention 95 to
It means that 5 to 40 parts by weight of the polyester resin or the styrene-acrylic copolymer is mixed with 60 parts by weight.

When the amount of the polyester resin or the styrene-acrylic copolymer is less than 5 parts by weight, no improvement in the offset property is observed, while when the amount exceeds 40 parts by weight, the negative charge property becomes strong, and it is difficult to control the polarity of the positive charge property. Also, toner transfer to a vinyl chloride resin sheet occurs. The mixing ratio of the polyester resin or the styrene-acrylic copolymer is preferably amine-modified epoxy resin 90 to
It is 10 to 25 parts by weight for 75 parts by weight.

The polyester resin used in the present invention is a thermoplastic saturated or unsaturated polyester obtained by condensation of a bisphenol type diol and a polyvalent carboxylic acid. Representative diols are shown below.

(A) Polyoxypropylene (2,2) -2,2-bis (4-
(B) polyoxyethylene (2) -2,2-bis (4-hydroxyphenyl) propane; (c) polyoxystyrene (6) -2,2-bis (4-hydroxyphenyl) propane (D) polyhydroxybutylene (2) -2,2-bis (4
(E) polyoxypropylene (3) -bis (4-hydroxyphenyl) thioether; (f) polyoxypropylene (2) -2,2-bis (4-
(G) polyoxyethylene (2) -2,6-dichloro-4
(H) polyoxyethylene (2,5) -p, p-bisphenol; (i) polyoxybutylene (4) bis (4-hydroxyphenyl) ketone; (j) polyoxyethylene-2,2 -Bis (4-hydroxyphenyl) propane; and (k) polyoxypropylene-2,2-bis (4-hydroxyphenyl) propane.

Examples of polycarboxylic acids include maleic acid, fumaric acid, glutaric acid, phthalic acid, maleic anhydride, fumaric anhydride, phthalic anhydride, isophthalic acid, terephthalic acid,
There are trimellitic acid and 1,2,4-benzenetricarboxylic acid.

Examples of polyester resins using these diols and polyvalent carboxylic acids include: Resin Example 1: Polyester having a softening point of 100 ° C. with the diol and fumaric acid of (a); Resin Example 2: of (b) Polyester having a softening point of 90 ° C with diol and terephthalic acid; Resin Example 3: Polyester having a softening point of 110 ° C with diol and isophthalic acid of (e); Resin Example 4: Diol, fumaric acid and triol of (a) Polyester having a softening point of 130 ° C with merit acid; and Resin Example 5: Polyester having a softening point of 100 ° C with the diol and fumaric acid of the above (j).

These resins may be used alone or in combination of two or more.

The styrene-acrylic copolymer used in the present invention may be any conventionally known resin, and may be obtained by copolymerizing a styrene monomer and an acrylate, or a methacrylate, or by partially cross-linking. It is obtained. Examples of the styrene monomer include styrene, α-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, 2,4-dimethylstyrene, and 3,4-dimethylstyrene. Examples of the acrylate include ethyl acrylate, methyl acrylate, propyl acrylate, n-butyl acrylate, isobutyl acrylate, dotesyl acrylate, 2-ethylhexyl acrylate, methacrylic acid, ethyl methacrylate, methyl methacrylate, and methacrylic acid. Propyl acrylate, n-butyl methacrylate, isobutyl methacrylate, dodecyl methacrylate, 2-ethylhexyl methacrylate and the like. Examples of the styrene acrylic copolymer include, for example, styrene-acryl copolymer, styrene-methyl methacrylate copolymer, styrene-
n-butyl acrylate copolymer, styrene-n-butyl methacrylate copolymer, styrene-diethylaminoethyl methacrylate copolymer, styrene-methyl methacrylate-n-butyl acrylate copolymer,
Styrene-methyl methacrylate-butyl acrylate-N- (ethoxymethyl) acrylamide copolymer,
Styrene-glycidyl methacrylate copolymer, styrene-dimethylaminoethyl methacrylate copolymer, styrene-diethylaminoethyl methacrylate copolymer, styrene-butadiene-acrylate copolymer, styrene-butadiene copolymer, styrene-
Butadiene-chlorinated paraffin copolymer, styrene-butadiene-dimethylaminoethyl methacrylate copolymer, styrene-acrylate-maleate copolymer, styrene-n-butyl acrylate-2
-Ethylhexyl acrylate copolymer, styrene-methyl methacrylate-acrylic acid-2-ethylhexyl copolymer, styrene-n-butyl acrylate-ethyl glycol methacrylate copolymer, and styrene-
Examples include n-butyl methacrylate-acrylic acid copolymer.

These resins may be used alone or in combination of two or more. As described above, the resin for a toner of the present invention is based on a blend of an amine-modified epoxy resin and a polyester resin or a styrene-acrylic copolymer resin, but the physical properties of the toner are determined by the properties of the amine-modified epoxy resin, Further, improvement in offset resistance and crushability can be obtained.

Next, other materials used for the dry toner of the present invention will be described.

First, as the coloring agent, all known dyes and pigments can be used. For example, carbon black, nigrosine dye, iron black, naphthol yellow S, Hansa yellow (10G, 5
G, G), cadmium yellow, yellow iron oxide, loess, graphite, titanium yellow, polyazo yellow, oil yellow, Hansa yellow (GR, A, RN, R), pigment yellow L, benzidine yellow (G, GR) , Permanent Yellow (NCG), Vulcan Fast Yellow (5G, R),
Tartrazine Lake, Quinoline Yellow Lake, Anthrazan Yellow BGL, Isoindolinone Yellow, Bengala, Lead Tan, Lead Powder, Cadmium Red, Cadmium Mercury Red, Antimony Vermilion, Permanent Red 4R,
Para Red, Phisae Red, Para Chlor Ortho Nitroaniline Red, Risol Fast Scarlet G,
Brilliant Fast Scarlet, Brilliant Carmine BS, Permanent Red (F2R, F4R, FRL, FRLL, F
4RH), Fast Scarlet VD, Belcan Fast Rubin B, Lithor Red, Lake Red (C, D), Anthosine B, Brilliant Scarlet G, Lisor Rubin GX, Permanent Red F5R, Brilliant Carmine 6B, Pigment Scarlet 3B, Bordeaux 5B, Toluidine Maroon , Permanent Bordeaux F2K, Helio Bordeaux BL, Bordeaux 10B, Bon Maroon Light, Bon Maroon Museum, Eoxi Lake, Rhodamine Lake B,
Rhodamine lake Y, alizarin lake, thioindigo red B, thioindigo maroon, oil red, quinacridone red, pyrazolone red, polyazo red, chrome permillion, benzidine orange, perinone orange, oil orange, cobalt blue, cerulean blue, alkali Blue Lake, Peacock Blue Lake, Victoria Blue Lake, Metal-Free Phthalocyanine Blue, Phthalocyanine Blue, Fast Sky Blue, Indanthrene Blue, (RS, BC), Indigo,
Ultramarine, Navy Blue, Anthraquinone Blur, Fast Violet B, Methyl Violet Lake, Cobalt Purple, Manganese Violet, Dioxane Violet, Anthraquinone Violet, Chrome Green, Zinc Green, Chromium Oxide, Pyridian, Emerald Green, Pigment Green B, Naphthol Green B , Green gold, acid green lake, malachite green lake, phthalocyanine green, anthraquinone green, titanium oxide, zinc white, lithopone, and mixtures thereof. The amount used is generally 0.1 parts by weight per 100 parts by weight of the binder resin.
5050 parts by weight.

The toner of the present invention may optionally contain a charge control agent. All known charge control agents can be used, for example, nigrosine dyes, triphenylmethane dyes, chromium-containing metal complex dyes, molybdate chelate pigments, rhodamine dyes, alkoxy amines, quaternary ammonium salts, alkylamides , Phosphorus simple substance or compound,
Tungsten alone or compound, fluorine-based activator, metal salt of salicylic acid and metal salt of salicylic acid derivative, hydrophobic silica and the like.

Other additives such as colloidal silica,
Hydrophobic silica, silicone oil, metal soap, nonionic surfactant, fatty acid metal salt (zinc stearate, aluminum stearate, etc.), metal oxide (titanium oxide, aluminum oxide, tin oxide, antimony oxide, etc.), fluoro It may contain a polymer or the like.

The toner of the present invention composed of the above materials may be used as a two-component developer together with a carrier, or may be used as a one-component developer with a carrier contained therein. As the carrier used here, iron powder, ferrite, glass beads and the like are the same as those in the related art. These carriers may be coated with a resin. The resin used in this case is carbon fluoride, polyvinyl chloride, polyvinylidene chloride, phenol resin, polyvinyl acetal, silicone resin, acrylic resin and the like. These may be used alone or in combination of two or more. In any case, the mixing ratio of the toner and the carrier is generally suitable for about 0.5 to 6.0 parts by weight of the toner per 100 parts by weight of the carrier.

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

Example 1 stirrer, thermometer, N ₂ inlet, bisphenol A type epoxy resin in a separable flask equipped with a cooling tube (EPOMIK
R140P, Mitsui Petrochemical) 250g, Bisphenol A117g,
50 ml of xylene was added, the temperature was raised under a N ₂ atmosphere, and 1 ml of a 0.65N aqueous sodium hydroxide solution was added. Thereafter, the temperature was raised to 150 ° C., and xylene was distilled off under reduced pressure. After the pressure was released, 11 g of stearylamine was added and reacted at 185 ° C. for 5 hours to obtain an amine-modified epoxy resin having a softening point of 142 ° C. (hereinafter referred to as resin A).

Next, the mixture of the following color toner formulations is melt-kneaded in a hot roll mill, cooled, coarsely pulverized by a hammer mill, and finely pulverized by an air jet pulverizer.
The toner was classified into particles having a particle size of m. The feed amount of the feeder in the fine pulverization was 580 g / hr.

Yellow toner formulation: Resin A 90 parts Polyester resin of Resin Example 1 10 parts Yellow pigment (Lionol Yellow FG manufactured by Toyo Ink Mfg. Co., Ltd.)
NT) 5 parts Magenta toner prescription: Resin A 90 parts Polyester resin of Resin Example 1 10 parts Red dye (Rionogen Magenta R manufactured by Toyo Ink Mfg. Co., Ltd.) 5 parts Cyan toner prescription: Resin A 90 parts The above resin examples 1 polyester resin 10 parts Blue pigment (Lionol Blue FG- manufactured by Toyo Ink Mfg. Co., Ltd.)
7351) 2 parts Next, 3.5 parts of each color toner were mixed with 96.5 parts of an iron powder carrier (TEFV23 manufactured by Nippon Iron Powder Co., Ltd.) to prepare a two-component developer of each color. When the charge amount of the obtained developer was measured by a blow-off method, it was yellow developer + 15.4 μc / g, magenta developer + 12.2 μc / g, and cyan developer + 13.2 μc / g.

Next, these three types of color developers are set in a commercially available electrophotographic copying machine for color (a modified Ricoh color 3000), developed for each color, and each toner image is transferred to copy paper. As a result, clear single-color images of yellow, magenta, and cyan were formed.

Also, a clear image was formed even in a fixed image of red, blue, and green by two-color superposition development. Further, a clear full-color image was obtained even with a fixed image obtained by three-color overlay development. The minimum fixing temperature is 110 ° C and the hot offset occurrence temperature is 1
90 ° C.

Further, when the full-color image was fixed on a transparent sheet for an overhead projector (OHP) and projected by the OHP, a clear full-color image without any turbidity was projected. Further, a full color image was subjected to a storage test in which a vinyl chloride resin sheet was brought into close contact with the sheet and left at room temperature for 180 hours. As a result, toner transfer to this sheet was not observed, and the full color image was favorably maintained.

When a running test was performed on up to 50,000 sheets by three-color superimposition development, no remarkable change was observed in the fixed image, and the 50,000th image was a clear image free from background smear and blur. The charge amount of the 50,000th sheet is yellow developer + 15.0μ.
c / g, magenta developer + 11.5 μc / g, cyan developer + 12.1
μc / g, and the charge was stable.

Example 2 Each color toner was prepared in the same manner as in Example 1 except that the resin A synthesized in Example 1 was used. The prescription is as follows.

Yellow toner formulation: Resin A 85 parts Resin example 4 polyester resin 15 parts Yellow pigment (Toyo Ink Mfg. Co., Ltd., Lionol Yellow FG)
NT) 5 parts Bontron P-51 manufactured by Orient Chemical Co., Ltd. 2 parts Magenta toner formulation: Resin A 85 parts Polyester resin of Resin Example 4 15 parts Red dye (Rionogen Magenta R manufactured by Toyo Ink Mfg.) 5 parts Bontron P-51 2 parts Cyan toner prescription: Resin A 85 parts Polyester resin of Resin Example 4 15 parts Blue pigment (Lionol Blue FG- manufactured by Toyo Ink Mfg. Co., Ltd.)
7351) 2 parts Bontron P-51 2 parts Next, 3.5 parts of each color toner was mixed with 96.5 parts of an iron powder carrier (TEFV23 manufactured by Nippon Iron Powder Co., Ltd.) to prepare a two-component developer of each color. The charge amount of the obtained developer is yellow developer + 1
6.0 μc / g, magenta developer + 14.2 μc / g, and cyan developer + 14.9 μc / g.

When an image was formed by a single color, a two-color superposition, and a three-color superposition using these developers, a clear fixed image was obtained in each of the single-color image, the two-color superposition image, and the three-color superposition full-color image. The minimum fixing temperature was 110 ° C., and the hot offset occurrence temperature was 200 ° C.

Furthermore, the projected image by OHP was clear, and there was no toner transfer to the vinyl chloride resin sheet.

No remarkable change was observed in both the image and the charge even in the running test of up to 50,000 sheets with three-color superposition.

Example 3 Synthesis was carried out in the same manner as in Example 1 except that 8 g of laurylamine was used instead of 11 g of stearylamine, to obtain an amine-modified epoxy resin having a softening point of 141 ° C. (hereinafter referred to as resin B). Next, using this resin B, yellow, magenta, and cyan color toners were produced in the same manner as in Example 1. The prescription is as follows.

Yellow toner formulation: Resin B 90 parts Polyester resin of Resin Example 3 10 parts Yellow pigment (Lionol Yellow FG manufactured by Toyo Ink Mfg. Co., Ltd.)
NT) 5 parts TP-302 manufactured by Hodogaya Chemical Co., Ltd. 1 part Magenta toner prescription: Resin B 90 parts Polyester resin of Resin Example 3 10 parts Red pigment (Rionogen Magenta R manufactured by Toyo Ink Mfg. Co., Ltd.) 5 parts TP-302 1 part Cyan toner formula: Resin B 90 parts Polyester resin of Resin Example 3 10 parts Blue pigment (Lionol Blue FG- manufactured by Toyo Ink Mfg. Co., Ltd.)
7351) 2 parts TP-302 1 part Next, in the same manner as in Example 1, yellow, magenta and cyan color toners and color developers were prepared,
When images were formed by two-color superposition and three-color superposition development, clear fixed images were obtained in both cases.

The image projected by the OHP was clear, and there was no toner transfer to the vinyl chloride resin sheet.

Even in a running test of up to 50,000 sheets with three-color superposition, no remarkable change was observed in both the image and the charging.

Example 4 In Example 3, the synthesis was carried out in the same manner as in Example 1 except that 5 g of octylamine was used instead of 8 g of laurylamine, to obtain an amine-modified epoxy resin (hereinafter referred to as resin C).

Next, yellow, magenta, and cyan toners were prepared in the same manner as in Example 1 using the resin C.

 The prescription is as follows.

Yellow toner formula: Resin C 85 parts Resin Example 5 polyester resin 15 parts Yellow pigment (Toyo Ink Mfg. Co., Ltd., Lionol Yellow FG)
NT) 5 parts Magenta toner formulation: Resin C 85 parts Polyester resin of Resin Example 5 15 parts Red pigment (Rionogen Magenta R manufactured by Toyo Ink Mfg. Co., Ltd.) 5 parts Cyan toner formulation: Resin C 85 parts The above resin examples 5 polyester resin 15 parts Blue pigment (Lionol Blue FG- manufactured by Toyo Ink Manufacturing Co., Ltd.)
7351) 2 parts TP-302 1 part In the same manner as in Example 1, yellow, magenta, and cyan color toners and color developers are prepared, and a single color
When an image was formed by color superposition and three-color superposition development, a clear fixed image was obtained in each case.

The projected image by OHP was clear, and no transfer to the vinyl chloride resin sheet was observed.

Even in a running test of up to 50,000 sheets with three-color superposition, no remarkable change was observed in both the image and the charging.

Example 5 A mixture of the following toner formulations using the resin A synthesized in Example 1 was melt-kneaded by a hot roll mill, cooled, coarsely ground by a hammer mill, and then finely ground by an air jet grinder. The powder was classified to a particle size of 5 to 15 μm to prepare a toner of each color. The feed amount of the feeder in fine powder is
It was 270 g / hr.

Yellow toner formulation: Resin A 90 parts Styrene-n-butyl methacrylate copolymer 10 parts Yellow pigment (Lionol Yellow FG manufactured by Toyo Ink Mfg. Co., Ltd.)
NT) 5 parts Magenta toner formulation: Resin A 90 parts Styrene-n-butyl methacrylate copolymer 10 parts Red pigment (Toyo Ink Mfg. Co., Ltd. Rionogen Magenta R) 5 parts Cyan toner formulation: Resin A 90 parts Styrene-n-butyl methacrylate copolymer 10 parts Blue pigment (Lionol Blue FG- manufactured by Toyo Ink Mfg. Co., Ltd.)
7351) 2 parts Next, 3.5 parts of each color toner were mixed with 96.5 parts of an iron powder carrier (TEFV23 manufactured by Nippon Iron Powder Co., Ltd.) to prepare a two-component developer of each color. The charge amount of the obtained developer was measured by a blow-off method, and was found to be 16.0 μc / g for yellow developer, 13.8 μc / g for magenta developer, and 14.7 μc / g for cyan developer.

Next, these three types of color developers are set in a commercially available electrophotographic copying machine for color (a modified Ricoh color 3000), developed for each color, and each toner image is transferred to copy paper. As a result, clear single-color images of yellow, magenta, and cyan were formed.

Also, a clear image was formed even in a fixed image of red, blue, and green by two-color superposition development. Further, a clear full-color image was obtained even with a fixed image obtained by three-color overlay development. The fixing lower limit temperature is 110 ° C, and the hot offset occurrence temperature is 2
It was 00 ° C.

Further, when the full-color image was fixed on a transparent sheet for an overhead projector (OHP) and projected by the OHP, a clear full-color image without any turbidity was projected. Further, a storage test was conducted in which the full-color image was brought into close contact with the vinyl chloride resin sheet and left at room temperature for 180 hours. As a result, no toner transfer to this sheet was observed, and the full-color image was favorably maintained.

When a running test was performed on up to 50,000 sheets by three-color superposition development, no remarkable change was observed in the fixed image, and the 50,000th sheet image was also a clear written image with no background smear or blur. The charge amount of the 50,000th sheet is yellow developer + 15.1
μc / g, magenta developer + 12.2 μc / g, cyan developer + 1
It was 4.0 μc / g, and the charge was stable.

Example 6 Each color toner was prepared in the same manner as in Example 5 using the resin A synthesized in Example 1. The prescription is as follows.

Yellow toner formulation: Resin A 85 parts Styrene-n-butyl acrylate-2-ethylhexyl acrylate copolymer 15 parts Yellow pigment (Lionol Yellow FG manufactured by Toyo Ink Mfg. Co., Ltd.)
NT) 5 parts Bontron P-51 manufactured by Orient Chemical Co. 2 parts Magenta toner formulation: Resin A 85 parts Styrene-n-butyl acrylate-2-ethylhexyl acrylate copolymer 15 parts Red pigment (Ryono manufactured by Toyo Ink Mfg. Co., Ltd.) Genmagenta R) 5 parts Bontron P-51 2 parts Cyan toner formulation: Resin A 85 parts Styrene-n-butyl acrylate-2-ethylhexyl acrylate copolymer 15 parts Blue pigment (Lionol Blue FG- manufactured by Toyo Ink Mfg. Co., Ltd.)
7351) 2 parts Bontron P-51 2 parts Next, 3.5 parts of each color toner was mixed with 96.5 parts of an iron powder carrier (TEFV23 manufactured by Nippon Iron Powder Co., Ltd.) to prepare a two-component developer of each color. The charge amount of the obtained developer was + for the yellow developer.
17.4 μc / g, magenta developer was +15.0 μc / g, and cyan developer was +16.9 μc / g.

When an image was formed by a single color, a two-color superposition and a three-color superposition using these developers, a clear fixed image was obtained for each of the single-color image, the two-color superposition image and the three-color superposition full-color image. The minimum fixing temperature was 100 ° C., and the hot offset occurrence temperature was 195 ° C.

Furthermore, the projected image by OHP was clear, and there was no toner transfer of the vinyl chloride resin sheet.

Even in a running test of up to 50,000 sheets with three-color superposition, no remarkable change was observed in both the image and the charging.

Example 7 Using the resin B synthesized in Example 3, toners of yellow, magenta and cyan were produced in the same manner as in Example 5. The prescription is as follows.

Yellow toner formulation: Resin B 90 parts Styrene-n-butyl methacrylate copolymer 10 parts Yellow pigment (Lionol Yellow FG manufactured by Toyo Ink Mfg. Co., Ltd.)
NT) 5 parts Hodogaya Chemical Co., Ltd. TP-302 1 part Magenta toner formulation: Resin B 90 parts Styrene-n-butyl methacrylate copolymer 10 parts Red pigment (Ryogen Magenta R manufactured by Toyo Ink Mfg. Co., Ltd.) 5 parts TP-302 1 part Cyan toner formulation: Resin B 90 parts Styrene-n-butyl methacrylate copolymer 10 parts Blue pigment (Lionol Blue FG- manufactured by Toyo Ink Mfg. Co., Ltd.)
7351) 2 parts TP-302 1 part Next, in the same manner as in Example 5, yellow, magenta, and cyan color toners and color developers are prepared, and similarly, image formation by single color, two-color superposition, and three-color superposition development is performed. As a result, clear fixed images were obtained in each case.

Furthermore, the projected image by OHP was clear, and there was no toner transfer of the vinyl chloride resin sheet.

Even in a running test of up to 50,000 sheets with three-color superposition, no remarkable change was observed in both the image and the charging.

Example 8 In the same manner as in Example 5 except that the resin C synthesized in Example 4 was used, yellow, magenta, and cyan color toners were produced. The prescription is as follows.

Yellow toner formulation: Resin C 85 parts Styrene-n-butyl acrylate-2-ethylhexyl acrylate copolymer 15 parts Yellow pigment (Lionol Yellow FG manufactured by Toyo Ink Mfg. Co., Ltd.)
NT) 5 parts Magenta toner formulation: Resin C 85 parts Styrene-n-butyl acrylate-2-ethylhexyl acrylate copolymer 15 parts Red pigment (Toyo Ink Mfg. Co., Ltd. Rionogen Magenta R) 5 parts Cyan toner formulation: Resin C 85 parts Styrene-n-butyl acrylate-2-ethylhexyl acrylate copolymer 15 parts Blue pigment (Lionol Blue FG- manufactured by Toyo Ink Mfg. Co., Ltd.)
7351) Part 2 Next, yellow, magenta, and cyan color toners and color developers were prepared in the same manner as in Example 1, and images were formed by single-color, two-color superposition, and three-color superposition development. Also, a clear fixed image was obtained.

The image projected by the OHP was clear, and no transfer to the vinyl chloride resin sheet was observed.

Even in a running test of up to 50,000 sheets with three-color superposition, no remarkable change was observed in both the image and the charging.

Comparative Example 1 Bisphenol A type epoxy resin (Epomic R368,
Yellow, magenta, and cyan toners were produced in the same manner as in Example 1 except that Mitsui Petrochemical Co., Ltd. was used as it was.

 The toner formulation is as follows.

Yellow toner formulation: R368 100 parts Lionol Yellow FGN-T 5 parts Magenta toner formulation: R368 100 parts Lionogen magenta R 5 parts Cyan toner formulation: R368 100 parts Lionol Blue FG-7351 2 parts The charge amount of the yellow developer is + 10.5μ
c / g, magenta developer +6.2 μc / g, cyan developer +
8.5 μc / g. When an image was formed by single-color, two-color superposition and three-color superposition development using these developers, fixed images were obtained for all of the single-color image, the two-color superposition image, and the three-color superposition image, but the background was slightly stained. Was. There was no toner transfer of the obtained image to the vinyl chloride resin sheet.

When a running test was performed by three-color superimposition development, the background dirt became severe on about 1000 sheets, transfer failure occurred, and no image was formed on 1600 sheets. At this stage, the charge amount of the developer was measured, and it was found that all three colors had negative polarity.

Comparative Example 2 Bisphenol A was used instead of the amine-modified epoxy resin.
A yellow toner, a magenta toner, and a cyan developer were prepared in the same manner and with the same prescription as in Example 1 except that the mold epoxy resin (R368, manufactured by Mitsui Petrochemical Company) was used as it was. The amount of charge of the obtained developer was +11.0 for the yellow developer.
μc / g, the magenta developer was +8.9 μc / g, and the cyan developer was +10.1 μc / g. When an image was formed by single-color, two-color superposition and three-color superposition development with these developers,
A fixed image was obtained for each of the single-color image, the two-color superimposed image, and the three-color superimposed image, but the image was slightly stained. There was no toner transfer of the obtained image to the vinyl chloride resin sheet.

When a running test was carried out by three-color superimposition development, the background stain became severe on about 3,000 sheets, transfer failure occurred, and no image was formed on 5,000 sheets. At this stage, the charge amount of the developer was measured, and it was found that all three colors had negative polarity.

Comparative Example 3 Bisphenol A was used instead of the amine-modified epoxy resin
Except that the epoxy resin (R368, manufactured by Mitsui Petrochemical Co., Ltd.) was used as it is, the same method and the same formulation as in Example 5
Magenta and cyan color toners and color developers were prepared. The charge amount of the obtained developer is +1 for the yellow developer.
1.6 µc / g, magenta developer +8.2 µc / g, cyan developer +9.8 µc / g. When an image was formed by single-color, two-color superposition and three-color superposition development with these developers,
A fixed image was obtained for each of the single-color image, the two-color superimposed image, and the three-color superimposed image, but the image was slightly stained. There was no toner transfer of the obtained image to the vinyl chloride resin sheet.

When a running test was carried out by three-color superimposition development, the background stain became severe on about 3,000 sheets, transfer failure occurred, and no image was formed on 5,000 sheets. At this stage, the charge amount of the developer was measured, and it was found that all three colors had negative polarity.

Comparative Example 4 Using the resin A synthesized in Example 1, a toner was produced in the same manner as in Example 1 according to the following formulation.

The feed amount of the feeder in the fine pulverization was only 170 g / hr.

Yellow toner prescription: Resin A 100 parts Lionol Yellow FGN-T 5 parts Magenta toner prescription: Resin A 100 parts Lionogen magenta R 5 parts Cyan toner prescription: Resin A 100 parts Lionol Blue FG-7351 2 parts Example 1 A developer was used in the same manner as described above. The charge amount of the obtained developer is yellow developer +17.5 μc / g, magenta developer +1
4.7 μc / g, cyan developer + 15.6 μc / g. Using these developers, fixed images were obtained by monochromatic, two-color superposition, and three-color superposition. The minimum fixing temperature was 110 ° C., and the hot offset occurrence temperature was 180 ° C.

Comparative Example 5 Each color toner was produced in the same manner as in Example 1 except that the amine-modified epoxy resin (hereinafter referred to as resin A) synthesized in Example 1 was used. The prescription is as follows.

Yellow toner formulation: Resin A 50 parts Styrene n-butyl methacrylate copolymer 50 parts Yellow pigment (Lionol Yellow FGN, manufactured by Toyo Nuki Manufacturing Co., Ltd.)
-T) 5 parts Magenta toner formulation: Resin A 50 parts Styrene n-butyl methacrylate copolymer 50 parts Red pigment (Toyo Ink Mfg. Co., Ltd. Rionogen Magenta R) 5 parts Cyan toner formulation: Resin A 50 parts Styrene n -Butyl methacrylate copolymer 50 parts Blue pigment (Lionol Blue FG manufactured by Toyo Ink Mfg. Co., Ltd.)
7351) 2 copies Each color developer was prepared and an image was formed in the same manner as in Example 1. When the obtained image was subjected to a storage test using a vinyl chloride resin sheet, the image was fused to the sheet, and the image was peeled off.

[Effects of the Invention] As described above, the dry electrophotographic toner of the present invention has good color reproducibility, stable positive charge, good compatibility with other resins, and good dispersibility of face wash. Good fixing properties and no transfer to PVC mat can be obtained.

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Kayo Makita 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Co., Ltd. (56) References JP-A-52-86334 (JP, A) 1-134466 (JP, A) JP-A-59-212847 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) G03G 9/087

Claims (1)

(57) [Claims] 1. A dry electrophotographic toner containing a colorant and a binder resin as main components, wherein the binder resin is obtained by reacting a liquid epoxy resin with a primary amine and a dihydric phenol. A modified epoxy resin, a polyester resin comprising a bisphenol-type diol and a polycarboxylic acid or a mixed system of a styrene-acrylic copolymer, wherein the amine-modified epoxy resin is 95 to 60 parts by weight, and the polyester resin or styrene is used. -Dry electrophotographic toner, characterized in that the acrylic copolymer is 5 to 40 parts by weight.