JPH10152636A - Magnetic ink - Google Patents

Abstract

PURPOSE: To obtain a magnetic ink which contains a magnetic material which is excellent in compatibility with and dispersibility in a vehicle and does not damage the color of a colorant by using a ferromagnetic org. high-molecular susbtance having a triarylmethane base structure as the magnetic material. CONSTITUTION: This ink mainly comprises a magnetic material, a colorant, and a vehicle. The magnetic material comprises a ferromagnetic org. susbtance having a triarylmethane base structure represented by the formula [wherein Ar<1> is a bicyclic or higher, optionally substd., fused polycyclic arylene group (provided it may contain a heteroatom selected from among N, S, and O as a cycle member) or a phenylene group substd. by an electron-donating group; Ar<2> is an optionally substd. aryl group; and n is an integer of 3 or higher] and having a free radical concn. at the methine carbon site of 10<17> /g or higher.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic ink, and more particularly to a magnetic ink useful for printing, ink jet printers, thermal transfer ribbons, hot melt printers, writing instruments, and the like.

[0002]

2. Description of the Related Art In general, a magnetic ink is composed of a vehicle in which a magnetic substance, a dye, a resin, a dispersion solvent, and the like are combined, an additive, and the like. I have.
For example, an ink in which a magnetic substance is colloidally dispersed in an organic solvent such as kerosene or glycerin or water (Japanese Patent Laid-Open No.
147217) and an ink in which a magnetic substance is dispersed in wax (Japanese Patent Application Laid-Open No. 62-267379).

[0003]

However, these magnetic inks have a magnetic substance of ferrite, chromium oxide, Mn-
Bi alloy, Mn-Al alloy, Fe-Ni alloy, Sn-F
Since it is made of a metal oxide such as an e-alloy, the compatibility between the magnetic material and the vehicle is poor, the magnetic material is easily aggregated, and the dispersibility is poor. In addition, cracks are likely to occur after the magnetic ink dries after image formation. Further, since the magnetic ink has a dark magnetic material (for example, black, black-brown, brown, etc.), it is difficult to color, and the colors of pigments and dyes are not reflected.

Accordingly, an object of the present invention is to solve the above-mentioned problems, that is, to provide a magnetic ink in which a magnetic substance has excellent compatibility with a vehicle or the like, has good dispersibility, and does not impair the color of a dye. .

[0005]

As a result of intensive studies, the present inventors have found that the above object can be achieved by using a ferromagnetic organic polymer having a triarylmethane structure as a magnetic substance. The present invention has been completed.

That is, according to the present invention, in a magnetic ink containing a magnetic substance, a dye and a vehicle as main components, the magnetic substance has a triarylmethane basic structure represented by the following general formula, and the methine carbon site A magnetic ink is provided, which is a ferromagnetic organic polymer having a radical concentration of at least 10 ¹⁷ / g.

Embedded image [Wherein, Ar ¹ , Ar ² and n each represent the following. Ar ¹ : a substituted or unsubstituted condensed polycyclic arylene group having two or more rings (however, a ring member may include a hetero atom composed of N, S or O) or an electron-donating group-substituted phenylene group. Ar ² : a substituted or unsubstituted aryl group. n: an integer of 3 or more. ]

Since the magnetic ink of the present invention uses a ferromagnetic organic polymer having a triarylmethane structure as a magnetic material, the magnetic ink has good compatibility with a vehicle and the like, and has excellent dispersibility of the magnetic material. It is easy to color, shows a vivid color, and according to the present magnetic ink, an excellent image can be obtained.

Hereinafter, the magnetic ink of the present invention will be described in detail. The magnetic ink of the present invention has a triarylmethane structure represented by the above general formula as a magnetic material, and further contains a ferromagnetic organic polymer substance having a radical concentration at its methine carbon site of at least 10 ¹⁷ / g. It is characterized by.

In the above formula, specific examples of the unsubstituted fused polycyclic arylene group having two or more rings of Ar ¹ include naphthyl, anthryl, phenanthryl, pyrenyl, chrysene, naphthacene, benzophenane Examples thereof include a tolyl group, a perylene group, a benzopyrenyl group, a coronene group, an acenaphthylene group, and a decacyclene group. Examples of the substituent include a hydroxyl group and a methyl group. The ring member may contain a hetero atom such as N, S, or O. Further, the electron-donating group-substituted phenylene group is a phenylene group having a hydroxy group, a methoxy group, a methyl group, an ethyl group, or the like as a substituent, and specific examples thereof include a phenol group and a resorcinol group.

Specific examples of the unsubstituted aryl group of Ar ² include a phenyl group and the like. Examples of the substituent include a nitro group, a methyl group, an isopropyl group, a t-butyl group, a hydroxyl group and an amino group. And the like. Note that n
Represents the degree of polymerization, and represents an integer of 3 or more, preferably 10 or more.

Specific examples of the polymer having a triarylmethane structure include those shown in Table 1 below.

[Table 1]

The ferromagnetic organic polymer having a triarylmethane structure represented by the above general formula has a radical concentration of at least 10 ¹⁷ at the methine carbon site.
/ G, but preferably at least 10 ¹⁸ / g. In addition, this polymer substance is described in, for example, JP-A-2-160.
No. 731 can be synthesized. In addition, since the color of this polymer substance is white to flaky, coloring is easy.

The magnetic ink of the present invention using the above magnetic material is manufactured as an oily, aqueous or hot melt ink.

For example, in the case of an oil-based magnetic ink, it is obtained with a composition comprising a vehicle and a combination of a magnetic substance, a dye, an oil, a resin and a dispersion solvent. In this case, specific examples of the dye include Fast Yellow G, Hansa Brilliant Yellow 5GX, Disazo Yellow A
AA, naphthol red HFG, lake red C, benzimidazolone carmine HF3C, dioxazine violet, phthalocyanine blue, indakotron blue, phthalocyanine green, benzimidazolone brown HFR, carbon black, aniline black, titanium oxide, tartrazine lake, Rhodamine 6G lake, methyl violet lake, basic 6G lake, brilliant green lake, nigrosine and the like.

The vehicle is composed of an oil, a resin, a dispersion solvent and the like. Specific examples of the oil include linseed oil, soybean oil, soybean oil, castor oil, dehydrated castor oil, lysovarnish, maleated oil, and vinylated oil. Oil, urethane oil, machine oil, spindle oil and the like. In addition, as the resin, rosin, shellac, copal, dammar, gilsonite,
Zein, lime rosin, ester gum, phenolic resin,
Xylene resin, urea resin, melamine resin, ketone resin,
Coumarone / indene resin, petroleum resin, terpene resin, cyclized rubber, chloride rubber, alkyd resin, polyamide resin, acrylic resin, polyvinyl chloride, vinyl chloride / vinyl acetate copolymer resin, polyvinyl acetate, polyvinyl alcohol,
Examples include polyvinyl butyral, chlorinated polypropylene, styrene resin, epoxy resin, polyurethane, and cellulose derivatives.

As the dispersion solvent, n-hexane,
n-heptane, toluene, xylene, methyl alcohol, isopropyl alcohol, ethylene glycol, triethylene glycol, diethylene glycol, glycerin, methyl cellosolve, carbitol, ethyl acetate,
Acetone, methyl ethyl ketone and the like can be mentioned.

The additives include a wax, a dryer, a dispersant, a wetting agent, a crosslinking agent, a stabilizer, a thickener, a gelling agent, a defoaming agent, and a photopolymerization initiator.

In the case of a hot melt magnetic ink,
It is obtained with a composition comprising a magnetic substance, a dye, a hot melt vehicle and additives. In this case, specific examples of the hot melt vehicle include carnauba wax, beeswax,
Anhydrous lanolin, paraffin wax, montan wax, ozokerite, ceresin, vaseline, polyethylene wax,
Paraffin chloride, fatty acid amide, phenyl salicylate,
Examples include triphenyl phosphate, n-heptyl p-hydroxybenzoate, dicyclohexyl phthalate, and the like. Specific examples of the dye and the additive include those similar to those of the oil-based magnetic ink.

In the case of the aqueous magnetic ink, it is obtained with a composition comprising a vehicle in which a magnetic substance, a dye, a resin, a water-solubilizing agent, a co-solvent, water and the like are combined, and additives. In this case, specific examples of the dye include those similar to those of the oil-based magnetic ink.

Specific examples of the resin include starch, dextrin, alginate, cellulose ester, polyvinyl alcohol, polyacrylamide, polyethylene oxide, shellac, styrenated shellac, rosin maleic resin, casein, acrylic copolymer, and vinyl acetate-based resin. Resin, vinyl chloride resin, synthetic rubber latex, polyurethane, polyester, alkyd resin, rosin ester,
Epoxy esters and the like can be mentioned. In addition, as a water-solubilizing agent, ammonia water, monoethanolamine, monoisopropanolamine, ethyl monoethanolamine,
Diethylethanolamine, dimethylethanolamine, morpholine and the like, and as a cosolvent,
Ethyl alcohol, isopropyl alcohol, ethyl acetate, methyl ethyl ketone and the like can be mentioned.

The additives include petroleum wax,
Examples of the agent include a friction resistance improver such as polyethylene wax, a nonionic activator, and a defoamer such as silicone and alcohol.

The magnetic ink thus obtained can be used for printing, ink jet printers, thermal transfer, hot melt printers, writing instruments, and the like.
Moreover, a magnetic signal can be added by the contained magnetic substance, and reading by a magnetic head is possible.
It can also be used for printing magnetic cards such as certificates and tickets, printing banknotes, adding information such as secret documents, or maintaining information. At that time, since the magnetic material is not colored, full color printing is possible, and the color of the dye is reflected as it is. Further, since the magnetic material has good compatibility with a resin or the like, the magnetic material has good dispersibility and does not cause cracks or the like after printing.

[0023]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, but it should not be construed that the present invention is limited thereto. The percentages shown below are all based on weight.

(Synthesis of Magnetic Material) Synthesis Example 1 5% PTS was added to a mixture of benzaldehyde and pyrene at a molar ratio of 1.25, mixed well, and reacted at 160 ° C. in an argon stream for 60 minutes to obtain a softening point of 80 ° C. 1.5 g of B stage resin was obtained. This was dissolved in 25 ml of chloroform, and about 1.5 g of benzoquinone was added.
Irradiated for 2 hours. This solution was poured into about 50 ml of methanol, and the precipitate was separated by filtration. The resulting precipitate was white and the yield was about 80%. Radical concentration by ESR is 10
¹⁹ to 10 ²⁰ / g. FIG. 1 shows the magnetization curve of the obtained precipitate.

Synthesis Example 2 1,6-Dihydroxynaphthalene and 1.25-fold molar benzaldehyde were mixed, 3% of PTS was added thereto, and the mixture was heated with stirring in a nitrogen stream. First 50
℃ for 1 hour, then raise the temperature to 100 ℃ for 1 hour,
Subsequently, the mixture was heated at 130 ° C. for 2 hours. Although still a viscous liquid at the reaction temperature, a dark red solid product was obtained at room temperature.

After pulverizing the solid product, benzoquinone is mixed in a 1.5-fold molar amount with respect to the structural unit, taken in a quartz test tube, and about 20 ml of dichloromethane is added. The benzoquinone dissolves, but the resin powder becomes suspended. This was irradiated with light using a 450 W high-pressure mercury lamp while stirring at room temperature for 12 hours. The sample solution after irradiation was poured into a large excess of dichloromethane, and the precipitate was separated by filtration. The yield was about 70%.

Synthesis Example 3 1% PTS was added to a mixture of benzaldehyde and phenol at a molar ratio of 1.25, and mixed well.
After reacting for 2 minutes, a red B-stage resin was obtained. After pulverizing this resin, 1 g of the resin and about 0.5 g of benzoquinone were dispersed in about 20 ml of cyclohexane, and this was irradiated with a high-pressure mercury lamp for 12 hours. After irradiation, the solution is
Poured into ml of cyclohexane and the precipitate was filtered off to give a red product. The yield was about 70-80%.

Synthesis Example 4 A 1.25-fold molar amount of benzaldehyde and PTS corresponding to 5% of the total weight thereof were added to carbazole and mixed well. Then, it was transferred to a test tube with branches and heated in an argon stream at 160 ° C. for 5 to 10 minutes to obtain a B-stage resin. 3 g of this B-stage resin was dissolved in 20 ml of dichloromethane, and this was poured into 60 ml of methanol. Since only the reaction product precipitated, it was separated by filtration to separate and remove the acid catalyst and unreacted substances.

The obtained resin was placed in a test tube, and benzoquinone (BQ) was added thereto in a 1.5-fold molar amount with respect to the structural unit of the reaction product. Then, about 10 ml of dichloromethane was added to the test tube to completely dissolve the mixture, and the mixture was stirred uniformly by ultrasonic waves. This was irradiated with light at room temperature for 24 hours using a high-pressure mercury lamp with an output of 450 W. The sample solution after irradiation was poured into methanol to precipitate the resin. After the precipitate was separated by filtration, the precipitate was transferred to a Soxhlet extractor, and the resin was washed with methanol as a solvent for 10 hours. The yield was about 70%.

Example 1 Disazo Yellow AAA 20% Phenol resin 25% Spindle oil 30% Toluene 13% Carnauba wax 5% Soybean oil fatty acid 2% Magnetic material obtained in Synthesis Example 1 5% The above components were mixed and dispersed. Thus, an oil-based magnetic ink was obtained.

When printing was performed on art paper using the obtained ink, the obtained printed matter was a clear and very good yellow image, and could be read by a magnetic head.

Example 2 Phthalocyanine blue 3.5% N-heptyl p-hydroxybenzoate 92.5% Magnetic material obtained in Synthesis Example 4 4.0% After sufficiently mixing and dissolving the above components, a membrane was prepared. Filtration was performed with a filter to obtain a hot melt magnetic ink.

When printing was performed with an ink jet printer using the obtained ink, the obtained printed matter was clear,
It was a very good blue image. Magnetic reading was also possible.

Example 3 Naphthol Red HFG 15.0% Shellac aqueous varnish 60.0% Polyethylene wax 4.0% Water 15.5% Silicone 0.5% Magnetic material obtained in Synthesis Example 3 5.0% The components were mixed to obtain an aqueous magnetic ink. (Note that
The composition of the above-mentioned shellac aqueous varnish is as follows: shellac 33%, monoethanolamine 2%, ethanol 13%, water 52%.
It is. )

When printing was performed using the obtained ink,
The resulting print was a clear, very good red image, and was magnetically readable.

[0036]

The magnetic ink of the present invention has a triarylmethane structure as a magnetic material, and uses a ferromagnetic organic polymer having a radical concentration at its methine carbon site of at least 10 ¹⁷ / g. Printing, inkjet printer, thermal transfer,
It can be used for hot melt printers, writing instruments, etc., and the contained magnetic material has no color, so it can be made full color, and it has good compatibility with resin etc.,
A clear and very good image can be obtained without generating cracks after printing. Further, the printed matter obtained by using the present magnetic ink can be read by a magnetic head, and can be used for printing of a certificate, a ticket or the like, printing of a bill, addition of information such as a secret document, and maintenance.

[Brief description of the drawings]

FIG. 1 is a graph showing a magnetization curve of a magnetic material having a triarylmethane structure obtained in Synthesis Example 1.

Claims (1)

[Claims] 1. A magnetic ink containing a magnetic material, a dye and a vehicle as main components, wherein the magnetic material has a triarylmethane basic structure represented by the following general formula, and has a radical concentration of at least 10 at a methine carbon site.
A magnetic ink, which is a ferromagnetic organic polymer substance having a density of ¹⁷ / g. Embedded image [Wherein, Ar ¹ , Ar ² and n each represent the following. Ar ¹ : a substituted or unsubstituted condensed polycyclic arylene group having two or more rings (however, a ring member may include a hetero atom composed of N, S or O) or an electron-donating group-substituted phenylene group. Ar ² : a substituted or unsubstituted aryl group. n: an integer of 3 or more. ]