JPH0394269A - Toner for dryelectrophotography - Google Patents

Abstract

PURPOSE:To provide the toner which has good color reproducibility, is chemically and biochemically stable and safe and is excellent in environmental stability and to obtain stable electrostatic chargeability to a positive polarity by specifying the respective ratios of a polyol resin and polyester resin constituting a binder resin. CONSTITUTION:The binder resin is formed by mixing 5 to 40pts.wt. polyester resin with 95 to 60pts.wt. polyol resin. The mixing ratio of the polyester resin is preferably 10 to 25pts.wt. per 90 to 75pts.wt. polyol resin. The basic skeleton of the polyol resin is obtd. by bringing an epoxy resin into reaction with primary amines and bivalent phenols to cause chain extension. The toner which has the excellent color reproducibility, is biochemically stable, is excellent in the environmental stability and has the stable positive chargeability is obtd. in this way.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to an improvement in a toner for dry electrophotography which mainly contains a colorant and a binder resin.

[Conventional technology]

In dry electrophotography, an electrostatic latent image is formed on a photoreceptor using a conventional method, and after development with dry toner, the toner image is transferred onto copy paper, and then thermally fixed (usually using a heated roller) to obtain a copy. ing. As is well known, the dry toner used in this method is mainly composed of a binder resin and a colorant, and if necessary, additives such as a charge control agent and an anti-offset agent are added thereto. Here, polystyrene, styrene, etc. are used as the binder resin in view of the properties required for toners, such as transparency, insulation, water resistance, fluidity (as a powder), mechanical strength, gloss, thermoplasticity, and pulverizability. Acrylic copolymers, polyester resins, epoxy resins, etc. are commonly used, and among them, styrene resins are widely used because of their excellent crushability, water resistance, and fluidity. However, in order to preserve copies obtained with styrene-based resin-containing toner, if they are 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 transfers to the fixed toner image, plasticizes it, and welds it to the sheet side. As a result, when the copy is removed from the sheet, the toner image partially or completely peels off from the copy, and The drawback was that the sheets also got dirty.

As a measure to prevent the above-mentioned transfer to vinyl chloride resin sheets, Japanese Patent Laid-Open No. 60-263951 and No. 61-2402 have been proposed.
No. 52 proposes blending styrene resin or polyester resin with an epoxy resin that is not plasticized with a vinyl chloride resin plasticizer.

However, when such blended resins are used especially for color toners, the incompatibility between different types of resins causes offset problems, curling of fixed images, and glossiness (in the case of a single color toner image, lack of gloss results in poor image quality). ), colorability, transparency, and color development become issues. Furthermore, various proposals have been made regarding epoxy resin toners mainly made of epoxy resins, but conventionally known epoxy resins do not necessarily have sufficient properties such as offset properties, curling of fixed images, and glossiness.

Another problem with epoxy resins is their reactivity with amines. In other words, epoxy resin is generally used as a resin with excellent mechanical strength and chemical resistance by reacting an epoxy group with a curing agent to create a crosslinked structure, but there are cases where amine-based resins are used as the cured product. Also, some of the dyes, pigments, and charge control agents that are kneaded together with resins in toners are amine-based.6 These amines may cause a crosslinking reaction with epoxy resins when mixed, so epoxy resins are not used in toners. There was a problem with including it in Moreover, the chemical activity of this epoxy group is considered to be biochemical, that is, toxic, such as skin irritation, and its presence requires careful attention.

Furthermore, since the epoxy group exhibits hydrophilic properties, it absorbs water significantly under high temperature and high humidity conditions, causing a decrease in charging, scumming, and poor cleaning. Another problem is the charging stability of epoxy resins. Generally, a 1-ner is composed of a binder resin, a colorant, a charge control agent, and the like. Various dyes and pigments are known as colorants, and some of them have charge control properties, and some have the dual function of being a colorant and a charge control agent. Although it is widely practiced to use an epoxy resin as a binder resin and form a toner with the above-mentioned composition, a problem arises in the dispersibility of dyes, pigments, charge control agents, and the like.

Generally, the mixing of binder resin, dyes, pigments, charge control agents, etc. is carried out in a heated roll mill, and it is necessary to uniformly disperse dyes, pigments, charge control agents, etc. in the binder resin. However, it is difficult to achieve sufficient dispersion, and poor dispersion of dyes and pigments as colorants results in poor color development and a low degree of coloration.
In addition, if the charge control agent is poorly dispersed, the charge distribution will be uneven, resulting in poor charging, scumming, and scattering. Lack of ID, absentmindedness,
This can cause various defects such as poor cleaning. Furthermore, JP-A No. 52-86334 discloses a product that has positive chargeability by reacting an aliphatic primary or secondary amine with the terminal epoxy group of a ready-made epoxy resin. Similarly, the epoxy group and the amine may cause a crosslinking reaction, making it impossible to use it as a toner. It also imparts positive chargeability, but it is difficult to set it to an arbitrary charge level in the epoxy group-clamping reaction. Furthermore, JP-A-52-156632 discloses reacting one or both of the terminal epoxy groups of an epoxy resin with alcohol, phenol, Grignard reagent, organic acid sodium acetylide, alkyl chloride, etc. However, if epoxy groups remain, problems such as reactivity with amines, toxicity, and wood affinity arise as described above. In addition, some of the above-mentioned reactants are hydrophilic, some affect charging, and some affect pulverization during toner production, and many problems still remain. [Problems to be Solved by the Invention] The first object of the present invention is to provide a toner for dry electrophotography with excellent color reproducibility. A second object of the present invention is to provide a dry electrophotographic toner that is stable against amine compounds and biochemically safe.

A third object of the present invention is to provide a dry electrophotographic toner with excellent environmental stability. A fourth object of the present invention is to provide a toner for dry electrophotography that is positively chargeable and stable.

A fifth object of the present invention is to provide a toner that has good compatibility with other resins and has good dispersion of dyes and pigments. A sixth object of the present invention is to provide a toner for dry electrophotography in which the toner image does not transfer to the vinyl chloride resin sheet even when the fixed image surface of the copy is brought into close contact with the sheet.

A seventh object of the present invention is to provide a toner with good crushability.

[Means to solve the problem]

The toner of the present invention is a dry electrophotographic toner containing a colorant and a binder resin as main components, in which the binder resin reacts an epoxy resin with a primary fi amine and a dihydric phenol to extend the chain length of the epoxy resin. It is a mixed system of a polyol resin obtained by reacting a monovalent active hydrogen-containing compound with the epoxy groups at both ends, and a polyester resin consisting of a bisphenol diol and a polyhydric carboxylic acid. 60 parts by weight, and the polyester resin is 5 to 40 parts by weight. As a result of various studies, the present inventors reacted the epoxy group of an epoxy resin with an active hydrogen compound to create a polyol resin in which a primary amine was introduced into the main chain of the epoxy resin, and used this as a binder resin. When used, it was found that the above purpose could be achieved.

According to the findings of the present inventors, epoxy resin has two epoxy groups in one molecule, and these groups are located at the ends of the molecular chain. By ring-opening the epoxy groups at both ends with a specific compound, a resin that is chemically stable, biologically safe, and has excellent environmental properties can be obtained.

The compounds used in the present invention to open the epoxy group are:
It is a compound that has monovalent active hydrogen in its molecule. Examples of such active hydrogen compounds include the following compounds, which can be used in one type or in a mixture of two or more types. Examples of monohydric phenols include phenol, cresol, isopropylphenol, aminophenol, nonylphenol, dodecylphenol, xylenol, and P-cumylphenol, and those having 6 to 40 carbon atoms are usually preferred. Monovalent carboxylic acids include acetic acid, propionic acid, caprylic acid, lauric acid, myristic acid, palmitic acid, stearic acid, acrylic acid, oleic acid,
margaric acid, alagic acid, linoleic acid, linolenic acid,
Examples include castor oil fatty acids and tall oil fatty acids, and those having 6 to 25 carbon atoms are usually preferred. The basic skeleton of the polyol resin according to the present invention is made by reacting an epoxy resin with primary amines and dihydric phenols to extend the chain length. The polyol resin of the present invention exhibits positive polarity due to the introduction of amine into the resin molecule. Compared to positively chargeable resins obtained by adding charge control agents or blending nitrogen-containing polymers, it has significantly improved charging stability and sufficient durability. Furthermore, it is possible to arbitrarily set the charging level depending on the amount introduced. Further, by introducing a primary amine having a long-chain alkyl group, the polyol resin of the present invention forms a comb-shaped structure, thereby improving the dispersibility of dyes and pigments and improving compatibility with other resins.

Specific examples of primary amines used in the present invention include propylamine, butylamine, hexylamine, octylamine, laurylamine, stearylamine, palmitylamine, oleylamine, etc. as aliphatic primary amines. , preferably one having 6 to 20 carbon atoms. In addition, aromatic primary amines include aniline, toluidine, xylidine, cumidine, hexylaniline, nonylaniline, dodecylaniline, etc.
Preferably, the benzene nucleus of aniline has 3 to 2 carbon atoms.
It is a compound with 0 alkyl groups bonded to it. The amount of amine introduced is 0.01 to 100 parts by weight of epoxy resin.
It is 1.00 parts by weight. A typical example of the epoxy resin used in the present invention is a polycondensate of bisphenol A and epichlorohydrin. Commercially available epoxy resins include Epomic R301. Epomic R30
2. Epomic R304. Epomic R304P, Epomic R307, Epomic R309, Epomic R3
62, Epomic R363, Epomic R364, Epomic R365, Epomic R366, Epomic R3
67 (manufactured by Mitsui Petrochemical Industries, Ltd.), etc.

Furthermore, there are also epoxy resins with arbitrary softening points obtained by polyaddition reaction between liquid epoxy resins and bisphenols. Evomic R1 is a commercially available liquid epoxy resin.
40, Epomic R139, Epomic R140P (manufactured by Mitsui Petrochemical Industries, Ltd.), etc., and bisphenols include bisphenol A, bisphenol F, bisphenol AD, etc. In this way, the above objectives can be achieved by carrying out the ring reaction between the terminals of the epoxy resin and the introduction of the amine into the main chain. Note that the end-to-end ring reaction does not in any way interfere with the purpose achieved by introducing the amine, and vice versa. Furthermore, the present inventors conducted various studies on the polyol resin of the present invention in order to obtain even better fixing properties without impairing its basic properties. It has been found that a mixed system with a polyester resin obtained from

This further improves the offset resistance and also improves the crushability during toner production. Since two different resins are blended, compatibility becomes an issue.
By regulating the mixing ratio, offset resistance can be improved without substantially impairing the basic properties of the polyol resin.

That is, the binder resin of the present invention is polyol resin 9
5-60 parts by weight, 5-4 parts of the polyester resin
0 parts by weight were mixed. If the amount of the polyester resin is less than 5 parts by weight, no improvement in offset properties is observed, while if it exceeds 40 parts by weight, the negative chargeability becomes strong and it becomes difficult to control the polarity of the positive chargeability. The mixing ratio of the polyester resin is preferably 10-25 parts by weight to 90-75 parts by weight of the polyol resin.

The polyester resin used in the present invention is a thermoplastic saturated or unsaturated polyester obtained by condensation of bisphenol diols and polyhydric carboxylic acids. Representative diols are shown below. (a) Polyoxypropylene (2.2)-2.2-bis(4-hydroxyphenyl)propane; (b) Polyoxyethylene (2)-2.2-bis(4-
(c) polyoxystyrene (6)-2,2-bis(4-
(d) Polyhydroxybutylene (2)-2,2-bis(hydroxyphenyl)propane;
4-hydroxyphenyl)propane; (e) polyoxypropylene (3) monobis(4-hydroxyphenyl)thioether: (f) polyoxypropylene (2)-2,2-bis(4)
-cyclohexanol)propane; (g) polyoxyethylene (2)-2,6-dichloro-
4-hydroxyphenyl; (h) polyoxyethylene (L5)-ptp-bisphenol; (i) polyoxybutylene (4) bis(4-hydroxyphenyl) ketone; (j) polyoxyethylene-2,2-bis( 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, trimellitic acid, 1,2.4 -benzenetricarboxylic acid, etc.

Examples of polyester resins using these diols and polyhydric carboxylic acids include: Resin Example 1: Polyester with a softening point of 100°C made from the above diol (a) and fumaric acid; Resin Example 2: The above diol (b) and terephthalic acid; Resin Example 3: Polyester with a softening point of 110°C and the above diol (Q) and isophthalic acid; Resin Example 4: The above diol (a), fumaric acid, and trimellitic acid Polyester with a softening point of 130° C. when mixed with an acid; and Resin Example 5: Polyester with a softening point of 100° C. when mixed with the diol (j) and fumaric acid. These resins may be used alone or in combination of two or more. As described above, the toner resin of the present invention is
Although it is a blend of a polyol resin and a polyester resin, the physical properties of the toner are determined by the properties of the polyol resin, and it also provides improved offset resistance and crushability. Next, other materials used in the dry toner of the present invention will be explained.

First, all known dyes and pigments can be used as colorants, such as carbon black, nigrosine dye, iron black,
Naphthol Yellow S, Hansa Yellow (10G, 5G
．． G), cadmium yellow, yellow iron oxide, loess,
Yellow ship, titanium yellow, polyazo yellow, oil yellow,
Hansa Yellow (GR.A, RN.R), Pigment Yellow, Benzidine Yellow (G.GR), Permanent Yellow (NCG), Vulcan Fast Yellow (5G, R). Tartrazine Lake, Quinoline Yellow Lake, Anthrazan Yellow BGL. Isoindolinone yellow, red red, lead red, lead vermilion, cadmium red, cadmium mercury red, antimony vermilion, permanent red 4R, rose red, phise red, parachlororthonitroaniline red, lithol fast scarlet G, brilliant fast scarlet, Brilliant Carmine BS, Permanent Red (F2R, F4R, FRL.FRLL, F4RH
), Fast Scarlet VD, Belcampus Rubin B, Lysol Red, Lake Red (C, O), Anthosine B, Brilliant Scarlet G, Lysol Rubin GX, Permanent Red F5R, Brilliant Carmine 6B, Pigment Scarlet 3B, Bordeaux 5B
, Toluidine Maroon, Permanent Bordeaux F2K,
Helioboride-BL, Bordeaux 10B, Bonmaroon Light, Bonmaroon Medium, Eosin Lake, Rhodamine Lake B, Rhodamine Lake Y, Alizarin Lake, Thioindigo Red B, Thioindigo Maroon, Oil Red, Oil Pink, Cinchona Acridone Red , birazolene red, polyazo red, chrome permillion, benzidine orange, perinone orange, oil orange, cobalt blue, cerulean blue, alkaline 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 blue, fast violet B, methyl violet lake, cobalt purple, manganese purple, 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 to 50 parts by weight per 100 parts by weight of the binder resin.

The toner of the present invention may contain a '#E electrical control agent, if necessary. All known charge control agents can be used, such as nigrosine dyes, triphenylmethane dyes, chromium-containing metal complex dyes, molybdate chelate pigments, rhodamine dyes, alkoxy amines, quaternary ammonium salts, and alkylamides. , phosphorus alone or in compounds;
These include tungsten alone or compounds, fluorine-based activators, metal salts of salicylic acid and metal salts of salicylic acid derivatives, and hydrophobic silica. Other additives include colloidal silica, hydrophobic silica, silicone oil, metal soap, nonionic surfactants, fatty acid metal salts (zinc stearate, aluminum stearate, etc.), metal oxides (titanium oxide,
(aluminum oxide, tin oxide, antimony oxide, etc.), fluoropolymers, etc. The toner of the present invention made of the above-mentioned materials may be used as a two-component developer together with a carrier, or may be used as a one-component developer containing a carrier.

The carriers used here include iron powder, ferrite,
Examples include conventionally known materials such as glass beads. In addition,
These carriers may be coated with resin. The resins used in this case include polyfluorocarbon, polyvinyl chloride, polyvinylidene chloride, phenol resin, polyvinyl acetal, silicone resin, and acrylic resin. These may be used alone or in combination of two or more. In any case, the mixing ratio of toner and carrier is generally 0.5 to 0.5 parts by weight of toner to 100 parts by weight of carrier.
Approximately 6.0 parts by weight is appropriate. [Examples] The present invention will be explained below using examples. All parts are by weight. Example 1 250 g of bisphenol A type epoxy resin (Epomiku Rl40P, manufactured by Mitsui Petrochemicals) was placed in a separable flask equipped with a stirrer/thermometer, N2 inlet, and cooling tube. Add 30 g of bisphenol AI, 29 g of P-cumylphenol, and 50 g of xylene, and raise the temperature to 70°C under N2 atmosphere.
A 5N aqueous lithium chloride solution was added, and the temperature was then raised to 150°C, during which time water and xylene were distilled off under reduced pressure. The reduced pressure was released, 12 g of stearylamine was added, and the mixture was reacted at 185° C. for 5 hours to obtain a polyol resin (hereinafter referred to as resin A) having a softening point of 142° C. and an N content of 0.14 weight meters.

When the epoxy equivalent of Resin A was measured by the hydrochloric acid-dioxane method, no reaction of epoxy groups was observed, confirming that there were no epoxy groups in Resin A and that all of them were ring-opened. Next, a mixture of the following color toner formulations is melt-kneaded using a hot roll mill, cooled, coarsely ground using a hammer mill, and then finely ground using an air jet grinder to produce a fine powder with a 5 to 15 mm diameter. Each color toner was made by classifying the particles into particle sizes. In addition, the feed amount of the feeder for fine pulverization is 560
g/hr.

Yellow Toner Formula: Resin A 90 parts Polyester of Resin Example 1 10 parts Magenta Toner Formula: Resin A 90 parts Polyester of Resin Example 1 10 parts Cyan Toner Formula: Resin A 90 parts Polyester of Resin Example 1 10 parts Used in magenta toner Although the red dye was amine-based, no crosslinking reaction was observed during cross-linking, and the dye could be made into a toner. Next, 3.5 parts of each color toner was mixed with 96.5 parts of iron powder carrier (TEFV23 manufactured by Nippon Tetsuko Co., Ltd.) to prepare various two-component type developers. When the charge amount of the obtained developer was measured by the blow-off method, the yellow developer was +15.0 μe/g, the magenta developer was +12.5 μc/g, and the cyan developer was +13
．． It was 3μc/g. Next, these three types of color developers are set in a commercially available color electrophotographic copying machine (an improved version of Ricoh's Color 3000), and each color is developed. After each toner image is transferred to copy paper, a heated roller Once the particles were fixed, clear single-color images of yellow, magenta, and cyan were formed. Clear images were also formed in red, blue, and green fixed images using two-color overlapping development. Furthermore, a clear full-color image was obtained even when the fixed image was developed using three-color overlapping development.
The lower limit fixing temperature was 110''C, and the hot offset generation temperature was 190'C.

When the above image forming experiment was conducted at 30°C and 90% high temperature and humidity, the fixed image showed ID defects, background smudges, transfer defects, and
Clear images were formed without any visible cracks.

In addition, a full-color image is displayed using an overhead projector (
When the image was fixed on a transparent OHP (OHP) sheet and projected using O}IP, a clear full-color image with no turbidity was projected. Furthermore, a storage test was conducted in which a full-color image was closely attached to a vinyl chloride resin sheet and left at room temperature for 180 hours, and no toner transfer to the sheet was observed, and the full-color image was maintained well.

In addition, when a running test was conducted up to 50,000 prints using three-color overlapping development, no significant change was observed in the fixed image, and the image on the 50,000th print was also a bright image with no background smudges or blurring. Also, the amount of charge on the 50,000th sheet is yellow developer + 1
4.5μc/g, magenta developer +11.1μc/g,
The cyan developer was +12.5 pc/g, and the charging was stable. In addition, a black toner was prepared using Resin A according to the following recipe in the same manner as described above. Resin A 90 parts Polyester of Resin Example 1 IO part Carbon black #44 (Mitsubishi Kasei Co., Ltd. $1) 12 parts This was similarly used as a developer and set in a commercially available electrophotographic copying machine (FT4820 manufactured by Ricoh Co., Ltd.) to form an image. As a result, a clear image emerged. Fixing lower limit temperature t;! 110℃,
The temperature at which hot offset occurred was 190°C. Even under high temperature and high humidity conditions, the image pattern was clear and undisturbed. No toner transfer of the fixed image to the vinyl chloride sheet was observed. On the other hand, when we conducted a running test with up to 50,000 sheets, we found that
Even after 10,000 images, the images were clear with no visible dirt or blurring. The amount of charge was initially +13.8 μc/g.
The charge was stable for the 50,000th sheet +12.0 μc/g. Example 2 When resin A synthesized in Example 1 was used to knead yellow, magenta, and cyan color toners in the same manner as in Example 1, toners could be formed without crosslinking.

The prescription is as follows. Yellow toner formulation: Resin A 90 parts Polyester of Resin Example 1 10 parts Lionol Yellow FGN-T (mentioned above) 5 parts TP-3
02 (manufactured by Hodogaya Chemical Industry Co., Ltd.) 1 part Magenta toner formulation: Resin A 90 parts Polyester of resin example 1 10 parts Oil pick #312 (mentioned above) 4 parts TP-3
02 (listed above) 1 part Cyan toner formulation: Resin A 90 parts Polyester of resin example 1 10 parts Lionol Blue FG-7351 (listed above) 2 parts TP-302 (listed above) 1
Next, the toner was used as a developer in the same manner as in Example 1. The charge amount of the obtained developer is yellow developer +16
．． 3 μc/g, magenta developer 13.1 p c/g
, cyan developer +14.0 μc/g. When monochromatic, two-color, and three-color superimposed images were formed using these developers in the same manner as in Example 1, clear fixed images were obtained for single-color images, two-color superimposed images, and three-color superimposed full-color images. Ta. The lower limit fixing temperature was 110°C, and the hot offset generation temperature was 190°C. Furthermore, when the above-mentioned image formation experiment was conducted under high temperature and high humidity conditions, no abnormal images were observed. Furthermore, the OHP projected image 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 of three-color overlay, no significant change was observed in the image or charge.Example 3 Using resin A synthesized in Example 1, yellow, magenta, and cyan were produced in the same manner as in Example 1. When the toners of each color (black and white) were kneaded, the toner could be formed without any crosslinking.The recipe is as follows.

Yellow Toner Formula 2 Resin A 85 parts Polyester of Resin Example 4 15 parts Lionol Yellow FGN-T (described above) 5 parts Bontron P-51 (Orient Chemical Co., Ltd. II) 2 parts Magenta Toner Formula: Resin A 85 parts Resin Example 4 15 parts Oil Pink #312 (see above) 4 parts Bontron P-51 (see above) 2 parts Cyan toner formulation: Resin A 85 parts Polyester of Resin Example 4 15 parts Lionor Blue FG-7351 (see above) 2 Part Bontron P-51 (mentioned above) 2 parts Black toner formulation: Resin A 85 parts Polyester of Resin Example 4 15 parts Carbon Black #44 (stated above) 12 parts Bontron P-51 (mentioned above) 2 parts Then, the above toner was used as a developer in the same manner as in Example 1. The charge amount of the obtained developer is yellow developer + 14.2
μc/g, magenta developer +11.4 μc/g, cyan developer +12.7 μc/g, black developer +12.9
It was μe/g. Using the obtained color developer, monochromatic and two-color
When forming images by overlapping colors and overlapping three colors,
Clear fixed images were obtained for a single color image, a two-color superimposed image, and a three-color superimposed full-color image.

The minimum fixing temperature was 110°C, and the hot offset generation temperature was 195°C. Furthermore, when the image forming experiment was conducted under high temperature and high humidity conditions, no abnormal images were observed.

Furthermore, the projected image by 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 of three-color overlay, no significant changes were observed in either image or charge.

Further, when images were formed using the black developer in the same manner as in Example 1, clear images were formed.

The minimum fixing temperature was 110°C, and the hot offset generation temperature was 195°C. Images were clear and undisturbed even under high temperature and high humidity conditions. No toner transfer of the fixed image to the vinyl chloride sheet was observed. Even in a running test of up to 50,000 sheets, both the image and charge remained stable, and no significant changes were observed.

Example 4 In Example 1, laurylamine was used instead of stearylamine, and the synthesis was carried out in the same manner as in Example 1, and a polyol resin (hereinafter referred to as resin Resin B) was obtained. When the epoxy equivalent of Resin B was measured in the same manner as Resin A, no reaction of the epoxy group was observed. Next, using this Resin B, the same procedure as in Example 1 was carried out. Yellow by the recipe of Example 2,
I made magenta and cyan toners. No crosslinking was observed due to crosstalk.

These toners were used as a developer in the same manner as in Example 1, and monochrome,
When images were formed by two-color superimposition and three-color superimposition, clear fixed images were obtained for single images, two-color superimposed images, and three-color superimposed full-color images. The minimum fixing temperature is 11
The temperature at which hot offset occurred was 190°C.
Further, when the image forming experiment was conducted under high temperature and high humidity, no abnormal images were observed.

Furthermore, the projected image by 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 of three-color overlapping, no significant changes were observed in either image or charging.

Example 5 Synthesis was carried out in the same manner as in Example 1 except that stearic acid was used instead of P-cumylphenol and cyclohexylamine was used instead of stearylamine, and the softening point was 143°C and the N content was 0. When the epoxy equivalent of Resin C was measured in the same manner as Resin A, no reaction of the epoxy groups was observed.

Next, using this resin C, Example 2 was carried out in the same manner as in Example 1.
Yellow, magenta, and cyan color toners were kneaded according to the following formula. There was no cross-linking and the toner could be formed. When images were formed using the same developer by single color, two-color stacking, and three-color stacking development, clear full-color images were obtained for single-color images, two-color stacking images, and three-color stacking images. A fixed image was obtained. The lower limit temperature for fixing was 110°C, and the temperature at which hot offset occurred was 190°C. Furthermore, no abnormal images were observed even under high temperature and high humidity conditions, and the images projected by OHP were clear, and no toner transfer to the vinyl chloride resin sheet was observed.

Furthermore, even in a running test of up to 50,000 sheets of three-color overlay, no significant change in image or charge was observed. A12
6g. Synthesis was carried out using 35 g of P-cumylphenol and 12 g of stearylamine to obtain a polyol resin (hereinafter referred to as resin D) having a softening point of 130°C.

When the epoxy equivalent of Resin D was measured in the same manner as Resin A, no reaction of the epoxy group was observed.

Next, yellow, magenta, cyan, and black toners were kneaded using Resin D in the same manner as in Example 1 according to the recipe of Example 3, and the toners were formed without crosslinking.

These toners were used as developers in the same manner as in Example 1, and when images were formed using the color developer in single color, two-color stacking, and 38-layer stacking, single-color images, two-color stacking images, and three-color stacking images were formed.
Clear fixed images were obtained, including full-color images with overlapping colors. The lower limit temperature for fixing was 100°C, and the temperature at which hot offset occurred was 195°C. Clear fixed images were obtained even under high temperature and high humidity conditions. Furthermore, the projected image by OHP was clear, and no toner transfer to the vinyl chloride resin sheet was observed.

Furthermore, even in a running test of up to 50,000 sheets of three-color overlay, no significant changes were observed in either image or charge. Furthermore, when images were formed using the black developer in the same manner as in Example 1, clear images were obtained both at room temperature and humidity, and at high and high temperatures.

Furthermore, no toner transfer to the vinyl chloride sheet of the fixed image was observed. Even in a running test of 50,000 sheets, no significant changes in image quality or charging were observed. Comparative example l Bisphenol^ type epoxy resin (Epomic S368
, Mitsui Petrochemical Co., Ltd.11) was used as it was, but Example 1
The toner was kneaded using the same recipe. Then, a crosslinking reaction occurred during the crosslinking of the magenta toner, and it solidified on the hot roll mill, making it impossible to form a toner.

When only yellow and cyan were converted into toner and used as a developer,
The amount of charge was +10.5 μc/g for the yellow developer and +8.5 μc/g for the cyan developer. An image was formed using a single color or a two-color superimposition, but the image looked a little smudged. Also, when similar image formation was performed under high temperature and high humidity,
The result was an abnormal image with smudges and smudges.

When we conducted a running test using two-color overlapping development,
After about 1,000 copies, the background smear became severe and transfer defects occurred, and after 1,600 copies, the image became unreliable.

At this point, when the amount of charge of the developer was measured, it was found that both colors had negative polarity.

Note that there was no toner transfer to the vinyl chloride sheet in the fixed images obtained in the initial stage. Comparative Example 2 Using the apparatus of Example 1, bisphenol A type resin 250
g, 139 g of bisphenol A, 30 g of ρ-cumylphenol, and 50 g of xylene were added. 70 under N2 atmosphere
The temperature was raised to 185°C, 1.8N aqueous lithium chloride solution was added, and the temperature was then raised to 185°C, during which time water and xylene were distilled off under reduced pressure. After the vacuum was released, the reaction was continued for another 5 hours to obtain a polyol resin with a softening point of 142°C.

No reaction of epoxy groups was observed in the obtained resin.

Next, using this resin, yellow, magenta, and cyan color toners were kneaded in the same manner as in Example 1.
The toner could be made without crosslinking or the like.

A developer was made from the obtained toner. Yellow developer +11.0μc/g, magenta developer +7.2μC
/g, cyan developer +9.0 pc/g. When images were formed by single-color, two-color superimposed, and three-color superimposed development using these developers, fixed images were obtained for single-color, two-color superimposed, and three-color superimposed images, but the images were slightly smudged. there were. Note that there was no toner transfer to the vinyl chloride resin sheet of the obtained image. Furthermore, when images were taken under high temperature and high humidity conditions, no abnormal images such as blurring were observed. However, when we conducted a running test using three-color overlapping development, we found that the background smearing became severe after about 100 sheets, and transfer defects occurred, and the image lost its shape after 1,600 sheets. At that stage, when we measured the amount of charge on the developer, we found that all three colors had negative polarity. Comparative Example 3 Using the apparatus of Example 1, 250 g of bisphenol A epoxy resin, 17 g of bisphenol AI, and 50 g of xylene were produced.
The mixture was heated under N2 atmosphere, and 1 mQ of 0.65N aqueous sodium hydroxide solution was added.

Thereafter, the temperature was raised to 150°C, and the pressure was reduced midway through to distill off the xylene. After releasing the reduced pressure, add 1 lb of stearylamine and add 1 lb of stearylamine.
The reaction was carried out at 85°C for 5 hours to obtain an amine-modified epoxy resin with a softening point of 142°C. When this resin was used to knead a toner with the same recipe as in Example 1, a crosslinking reaction occurred during the crosslinking of the magenta toner, which solidified on a hot roll mill, making it impossible to form a toner.

When only yellow and cyan were converted into toner and used as a developer,
The charge amount was +17.6 μc/g for the yellow developer and 15.2 μc/g for the cyan developer.

I was able to form images using single color and two-color stacking, but when I tried to create the same image shape under high temperature and high humidity, the result was an abnormal image with background smudges and unevenness. When a running test was conducted up to 10,000 sheets, no significant change was observed in the fixed image, and the 50,000th image was also a clear image without background smudges or shading. Further, the charge amount for the 50,000th sheet was +15.8 μc/g for the yellow developer and ◆13.9 μc/g for the cyan developer, and the charging was stable.

Comparative Example 4 Using Resin A synthesized in Example 1, a toner was made in the same manner as in Example 1 according to the following formulation. No crosslinking reaction was observed during crosstalk. However, the feed rate of the feeder during fine pulverization was only 150 g/hr L. Yellow toner formulation: Resin AI 00 parts Lionol Yellow FGN-T (mentioned above) 5 parts Magenta toner formulation: Resin A 100 parts Oil Pink #312 (mentioned above) 5 parts Cyan toner formulation: Resin A 100 parts Lionor Blue FG- 7351 (supra) 2 parts These toners were used as a developer in the same manner as in Example 1. The amount of charge of the obtained developer is yellow developer + 11.2pc7
g. The magenta developer was ◆14.0 μc/g, and the cyan developer was ÷15.5 μc/g. When images were formed using single color, two-color overlap, and three-color overlap, the minimum fixing temperature was 110.
℃, but hot offset occurred at 180℃.

〔Effect of the invention〕

Claims (1)

[Claims] (1) In a dry electrophotographic toner containing a colorant and a binder resin as main components, the binder resin reacts an epoxy resin with a primary amine and a dihydric phenol to extend the chain length of the epoxy resin. 1 on the terminal epoxy group
It is a mixed system of a polyol resin obtained by reacting a polyhydric active hydrogen-containing compound with a polyester resin consisting of a bisphenol diol and a polyhydric carboxylic acid, and the polyol resin is 95 to 60 parts by weight, and the polyester resin is 95 to 60 parts by weight. A toner for dry electrophotography, characterized in that the resin is contained in an amount of 5 to 40 parts by weight.