JPH01173059A - Light transmittable color toner - Google Patents

Abstract

PURPOSE:To obtain a sharp color by using a light transmittable color toner contg. the polymer obtd. by polymerizing a radical-polymerizable monomer having a specific rhodanine deriv. in the presence of a radical initiator. CONSTITUTION:The light transmittable color toner contains the polymer obtd. by polymerizing the radical-polymerizable monomer having the rhodanine deriv. expressed by formula I in the presence of the radical initiator. The rhodanine ring part of the polymer is considered to be an electron acceptor and the quinoline group part constitutes to be an electron donor and this polymer forms the color by forming an intra-molecular charge transfer type complex by the visible light. Namely, said polymer forms the color by absorbing light energy at the time of transition of the pi electron nonlocalized in the electron donor of the ground state to the unoccupied orbital of the electron acceptor through the pi group [=C=CH-CH=]. In formula I, (C) denotes a divalent org. group; R1 denotes a lower alkyl group of 1-6C, substd. or unsubstd. aryl group, hydro gen group; P denotes 0 or 1.

Description

Detailed Description of the Invention <Industrial Application Field> The present invention relates to a color toner used for developing color electrophotography, and in particular to a light-transparent color toner constituting a developed image transferred to a light-transparent sheet. Regarding.

<Prior art> Overhead projector (OHP) that enlarges and projects manuscripts, etc. on a screen during conferences and research presentations.
is frequently used. In this OHP, an original image is formed on a transparent sheet, and the original image is projected onto the screen by applying light that has passed through the transparent sheet to a screen.

When using such an OHP, attempts have been made to emphasize and identify specific characters, etc. in an image using a color other than black. For this purpose, it is necessary to form a developed image using a color toner other than black on the transparent sheet.

<Problems to be Solved by the Invention> However, commonly used light-transmitting color toners are obtained by dispersing colored pigments in resin, so the light that enters the toner is scattered by the pigments. As a result, it loses its translucency.Therefore, a coloring agent with excellent translucency is required.

The present invention is intended to solve the above problems,
The purpose of this is to have sufficient translucency even when transferred to a translucent sheet, so that the developed image can be transferred to a translucent sheet using a normal method and then projected onto a screen using an OHP. The purpose of the present invention is to provide a color toner that can provide vivid colors.

<Means for Solving the Problems> The present invention is based on the following general formula (where C is a divalent organic group, R3 is a lower alkyl group having 1 to 6 carbon atoms, or a substituted or unsubstituted oryl group). , hydrogen atom,
A light-transmitting color toner containing a polymer obtained by polymerizing a radically polymerizable monomer having a rhodanine derivative represented by a hydroxyl group (P represents 0 or 1) in the presence of a radical initiator, It accomplishes its purpose.

The polymer used in the light-transmitting color toner of the present invention is notable for having a rhodanine ring and a quinoline group introduced at the 5-position of the rhodanine ring via an ethanediilidene group in the molecular chain. It is a characteristic. In the above polymer, the rhodanine ring portion is considered to be an electron acceptor, and the quinoline group is considered to be an electron donor, and forms an intramolecular charge transfer type complex when exposed to visible light. In other words,
The π electrons delocalized in the ground state electron donor form the group r
=C=CH-CI (=C=CH-CI absorbs light energy and develops color when it transfers to the vacant orbital of the electron acceptor through =J. In particular, since the quinoline group has an ethanediylidene group at the 2-position, the electron donor The electron donating property increases, and as a result, light absorption appears in a relatively long wavelength region (658 nm) in the visible light region.

When the above-mentioned polymer is used as a coloring agent for a toner, since it is a blue polymer itself with excellent translucency, a translucent toner can be obtained simply by granulating it.

Furthermore, in the present invention, since the radically polymerizable monomer having a rhodanine derivative is polymerized in the presence of a radical initiator, the rhodanine derivative is regularly introduced into the side chain of the chain polymer. Therefore, since the number of rhodanine derivatives present in the polymer increases, the toner obtained by granulating this polymer exhibits a clearer image.

Furthermore, since there is no need to add a colorant, it is possible to obtain a toner with excellent moisture resistance and no humidity dependence.

The present invention will be explained in detail below.

The polymer used in the light-transmitting color toner of the present invention is obtained by bonding a rhodanine derivative having a reactive substituent to a monomer having a functional group for polymerization and a reactive substituent, is obtained by polymerizing using an initiator.

A rhodanine derivative having such a reactive substituent has the following general formula (%) (in the formula, B is a reactive substituent, C is a divalent organic group,
R1 represents a lower alkyl group or a hydroxyl group. C
Examples include alkylene groups having 4 or less carbon atoms, arylene groups such as phenylene groups, and carbonyloxyalkylene groups such as carbonyloxyethyl and carbonyloxypropylene groups. Examples of the alkyl group for Ro include lower alkyl groups such as methyl, ethyl, propyl, butyl, pentyl, and hexyl groups, and examples of the alkyl group that may have a substituent include phenyl, naphthyl, Examples include anthryl, phenanthryl, fluorenyl, etc. Substituents include lower alkyl groups having 1 to 4 carbon atoms, alkoxy groups such as methoxy, ethoxy, and propoxy, amino groups, and alkyl groups such as dimethylamino, diethylamino, and dipropylamino groups. Examples include an amino group and a halogen atom.

Specifically, as shown in the above specific example, the reactive substituent B is -C
OOH9-CHzCl, -OH, -COCI, -
N)lz etc. are exemplified.

These rhodanine derivatives can be synthesized by various methods, such as the following reaction formula.

S (in the formula, B and R are the same as above) That is, the rhodanine derivative is a 3-substituted rhodanine and a 2-substituted rhodanine.
It can be obtained by reacting -β-acetanilide vinylquinoline alkyl iodide in alcohol.

A monomer having a functional group for polymerization and a reactive substituent for bonding the rhodanine derivative described above is represented by the following general formula % (wherein m represents an integer of O to 3). The olefinic monomer represented by the following general formula % formula % (wherein Rz is -CHzC1, -NHz, -3OzC1,
-COOH), an acrylic or methacrylic monomer represented by the general formula % (in which R5 is a hydrogen atom or a methyl group, and m is an integer from 0 to 3). A monomer is exemplified.

The reaction between the monomer and the rhodanine derivative is achieved, for example, by the following reaction formula.

(The following is a blank space) +1 S As the alkali, pyridine, triethylamine, etc. are used.

The polymers of the present invention in which rhodanine derivatives are regularly supported on the side chains of chain polymers are polymers and copolymers of the above-mentioned monomers, and are It is easily polymerized by heating in the presence of radical initiators such as azo compounds such as bisisobutylnitrile, and peroxides such as benzoyl peroxide, cumene hydroperoxide, t-butyl hydroperoxide, and lauroyl peroxide. .

The radical initiator concentration is 0 relative to the number of moles of the monomers.
．． It is preferably 1 to 0.01 mol%. The polymerization temperature varies depending on the type of radical initiator used, but is usually preferably 20 to 100°C.

Moreover, the polymerization time is preferably 20 to 50 hours. The molecular weight of the resulting polymer can be varied from 1o, ooo to 40.0, depending on the monomer concentration, radical initiator concentration, and polymerization temperature.
It can be adjusted widely within the range of 000.

In the light-transmitting color toner of the present invention, the above polymer alone can be granulated to form a toner powder, but various binder resins can be used in combination for the purpose of improving the properties of the toner. .

The binder resin is preferably a translucent styrene polymer, acrylic polymer, methacrylic polymer, or styrene-acrylic polymer.

Examples of unsaturated monomers used in the above-mentioned polymers include styrene, α-methylstyrene, 0-methylstyrene, p-
Styrenic monomers such as methylstyrene, p-methoxystyrene, p-chlorostyrene; acrylic acid, methyl acrylate, ethyl acrylate, n-butyl acrylate,
Isobutyl acrylate, n-octyl acrylate, 2-ethylhexyl acrylate, dodecyl acrylate,
Stearyl acrylate, cyclohexyl acrylate, phenyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, glycidyl acrylate, diethylaminoethyl acrylate, acrylamide, acrylonitrile, methacrylic acid, methyl methacrylate, ethyl methacrylate , n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, 2-ethylhexyl methacrylate, dodecyl methacrylate, stearyl methacrylate, cyclohexyl methacrylate, phenyl methacrylate, glycidyl methacrylate, 2-methacrylate Examples include acrylic or methacrylic monomers such as -hydroxyethyl, -2-hydroxypropyl methacrylate, and diethylaminoethyl methacrylate. The above monomers may be used singly or in a mixture of two or more.

These polymers have a weight average molecular weight of 30,000 to 20
0,000, in particular, so, ooo to 15o, ooo are preferable, and one type or a mixture of two or more types are used.

Further, as other toner additives, colorless toner additives that do not adversely affect the color of the toner, such as charge control agents, offset inhibitors, etc., can be added according to well-known formulations.

Examples of the charge control agent include naphthenic acid, salicylic acid, octylic acid, metal soaps that are metal salts of manganese, iron, cobalt, lead, zinc, cerium, calcium, nickel, etc. of fatty acids and resin acids, and metal-containing azosols. Examples include dyes, pyrimidine compounds, alkyl salicylic acid metal chelates, and preferably 0.1 to 10% by weight per toner.

The anti-offset agent may be a polyamide resin that has good compatibility with the binder resin and has transparency, such as 11-nylon, which is a polymer of ω-aminoundecanoic acid, or 12-nylon, which is a ring-opening polymer of laurolactam. - Nylon, 6,10-nylon, which is a polymer of hexamethylene diamine, sebacic acid, and dodecasine dicarboxylic acid, 6.12-
It is preferable that 1 to 20 parts by weight, particularly 5 to 10 parts by weight, of nylon, a polyamide resin which is a polymer of the alkyl diamine and dimer acid, etc., is added to 100 parts by weight of the binder resin.

In addition, the method for producing the toner of the present invention includes mixing a polymer having a rhodanine derivative, other additives, reinforcing resin, etc., melting and kneading the mixture using a heating kneader such as a hot roll or an extruder, and then melting and kneading the mixture using a hammer mill, The process consists of pulverizing with a pulverizer such as a jet mill and classifying with a classifier in order to make the particles uniform in predetermined particle size.

Experimental example Hereinafter, the present invention will be explained in more detail based on Examples.

(Example 1) [Synthesis of rhodanine derivative] Synthesis of 3-carboxymethyl-5-(2-(3-ethylquinoline)dimetine) rhodanine 19.1 g of 3-carboxymethyl rhodanine and 2-β-acetanilide vinylquinoline After refluxing 46.6 g of ethiodide and 12.1 g of triethylamine in ethanol for 30 minutes, the product was recrystallized from pyridine to obtain the above compound (yield: 50%).

[Synthesis of monomer bound to rhodanine derivative] 3-(p
Synthesis of rhodanine (vinylbenzyl)-5-(2-(3-ethylquinoline)dimethine) 15.2 g of p-chloromethylstyrene and 3-carboxymethyl-5-(2-(3
-ethylquinoline)dimethine] 1.2 g of rhodanine and 12 ml of triethylamine are dissolved in 100 ml of dimethylformamide and reacted at 90°C for 3 hours. After the reaction,
The above monomer was obtained by pouring the solution into water, washing the resulting precipitate with water, and recrystallizing it with acetone.

[Solution polymerization]

Monomer 3-(p-vinylbenzyl)- obtained above
5-(2-(3-ethylquinoline)dimethine) 4.3 g of rhodanine and α as a polymerization initiator.

After dissolving the above mixture, 6 mg of α'-azobisisobutyronitrile and 5 ml of tetrahydrofuran were added as a solvent, and the mixture was charged during polymerization and degassing was repeated several times to prepare an ampoule under sufficient vacuum using the sealed tube method.

This was immersed in a 60° C. constant temperature bath for 30 hours to obtain 4.0 g of the polymer of the present invention.

[Preparation of toner]

・Polystyrene carrying the above 5-(2-(3-ethylquinoline)dimethine)rhodanine on its side chain
100 parts by weight Bontron E-84
(manufactured by Orient Chemical Co., Ltd.), mixed uniformly using a Henschel mixer FM20B (manufactured by Mitsui Miike Kakoki Co., Ltd.), and then transferred to a twin-screw extruder PCM.
-30 (manufactured by Member Iron Works Co., Ltd.), and was melt-kneaded and solidified with cold air. Next, the coarsely pulverized product was coarsely pulverized using a feather mill (manufactured by Micron Co., Ltd. for wire use), and the coarsely pulverized product was pulverized using a jet mill ID5-5 (manufactured by Nippon Pneumatic Co., Ltd.). A blue toner with an average particle size of 11 μm was obtained by removing fine powder with a particle size of 5 μm or less.

To 100 parts by weight of the above blue toner, 0.5 parts by weight of Aerosil R972 (manufactured by Nippon Aerosil Co., Ltd.), which is a hydrophobic silica as a fluidity imparting agent, was added, and after surface treatment using a Henschel mixer, the aggregates were formed using a vibrating sieve. was removed. Then, the above toner and ferrite carrier (average particle size 70 μm 1 manufactured by Nippon Tetsuko Co., Ltd.) were mixed using a Nauta mixer.
A developer having a toner concentration of 4.5% by weight was prepared.

(Example 2) - 100 parts by weight of polystyrene carrying the rhodanine derivative used in Example 1 on its side chain - Styrene-acrylic copolymer (XPA 525 manufactured by Mitsui Toatsu Kogyo Co., Ltd.)
) 50 parts by weight, Bontron E-84 (manufactured by Orient Chemical Co., Ltd.), 3 parts by weight, and 5 parts by weight of polyamide resin having a structural unit of 12 nylon (X4434, manufactured by Daicel-Hüls). A blue toner and developer were prepared.

(Comparative example) - Eisenspiron Blue GN) l (manufactured by Hodogaya Chemical Co., Ltd.) 1.5 parts by weight - Styrene-acrylic copolymer (manufactured by Mitsui Toatsu Kogyo Co., Ltd.
A blue toner and developer were prepared in the same manner as in Example 1 using 100 parts by weight of PA 525) and 3 parts by weight of Bontron E-84 (manufactured by Orient Chemical Co., Ltd.).

(Evaluation) Using the toners of Examples 1 and 2 and Comparative Example produced as described above, a document image was developed using a normal color electrophotographic copying machine (DC-2055 manufactured by Sanda Kogyo Co., Ltd.), and the developed image was was transferred and fixed onto a translucent sheet (polyethylene terephthalate).

When the images were projected onto a white projection surface using OHP, the images of Examples 1 and 2 had clearer colors than the images of Comparative Example.

<Effects of the Invention> According to the present invention, as described above, by using a polymer having rhodanine Pi bodies regularly in the side chains of a chain polymer as a coloring agent, a blue color with excellent translucency can be produced. Toner can be obtained and OHP's: Therefore, it becomes possible to project a clear color image on the screen.

Patent applicant: Mita Kogyo Co., Ltd.

Claims (1)

[Claims] The following general formula ▲ Numerical formula, chemical formula, table, etc. ▼ (In the formula, C is a divalent organic group, R_1 is a lower alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted aryl group, A light-transmitting color toner containing a polymer obtained by polymerizing a radically polymerizable monomer having a rhodanine derivative represented by a hydrogen atom, a hydroxyl group, and P represents 0 or 1 in the presence of a radical initiator. .