JPS61164836A - Recording method - Google Patents

Abstract

PURPOSE:To enable the application on non-ink absorptive materials to be printed by a method wherein, a recording liquid is ejected and flown to a material to be printed and after recording, the adhered liquid droplets are cured by the irradiation of ultraviolet rays. CONSTITUTION:A film filter 1 excellent in heat resistance, solvent resistance, abrasion resistance and mechanical strength is provided the arrangement of minute pores 2. As a heat generator, a thermal head generally used at present in thermal printing is employed. An ordinary colorant is dissolved in monomer and/or prepolymer or solvent. An initiator of photo-polymerization is of a nature generating Lewis acid by the irradiation of ultraviolet rays, and it is preferable that the recording liquid 3 contains a component to be vaporized when heated. The recording liquid 3 being immersed in a felt 4 is fed into the pores 2 perforated in the film surface 1 uniformly. Said film is moved freely on a thermal head 5 in accordance with an inputted signal. Onto a film 6, positioned opposite to the thermal head, the recording liquid is transferred into the plurality of minute pores in the film filter 1 which is ejected and flown thereby forming desired images thereon. After that, the adhered droplets are cured by the irradiation of UV rays and volatile component is removed by blowing heated air. As described above, the formed image is a hardened one, it is made possible to perform printing on non-ink absorptive materials.

Description

Detailed Description of the Invention [Objective of the Invention] (Industrial Application Field) The present invention supplies a recording liquid containing an ultraviolet curable monomer and/or prepolymer to a film having many minute holes. The present invention relates to a recording method in which recording is performed by selectively heating and discharging the recording liquid in the microholes by the action of a heat generating section 9, and then curing by irradiating ultraviolet rays.

(Prior Art) While the spectacular development of office automation is progressing, one field that is currently lagging behind in development is the field of printers for producing hard copies.

Currently, the mainstream printer is the wire dot type impact printer.

However, this method has problems such as slow speed and strong noise, and is problematic as a high-speed output device or OA [device].

Therefore, quiet non-impact printers attracted attention.
Although there are various methods to date, the one that has received particular attention is the inkjet method.

This inkjet method is quiet, has low running costs, and can use plain paper. Although it has many advantages such as not requiring special fixing processing and being easy to colorize, it also has problems such as lack of reliability against nozzle clogging and the need for maintenance. In connection with this, curable binders and pigments cannot be used. For this reason, apart from printing on paper, many problems remain, such as the difficulty of applying it to non-absorbent printing materials such as metals, plastics, and glass.

(Problems to be Solved by the Present Invention) The present invention attempts to solve the problems caused by the above-mentioned inkjet method.

[Structure of the invention]

(Means for Solving the Problems) The present invention applies a recording liquid to a film having minute holes regularly or irregularly, supplies the recording liquid to the liquid holes, and then generates heat according to an input signal. The recording liquid in the hole is heated by bringing the heat-generating part into contact with the recording liquid, and the energy generated by thermal expansion of the recording liquid or vaporization of the recording liquid due to the heating causes the recording liquid to be transferred from the minute hole in the film to the recording medium. In a recording method in which recording is performed by flying discharge, the recording liquid includes a colorant (A) such as a dye or pigment, a monomer and/or prepolymer (B) that can be cured by ultraviolet irradiation, and a photopolymerization initiator. (C) and, if necessary, a solvent (D), is used to provide a recording method characterized in that after recording, a recording liquid on a recording medium is irradiated with ultraviolet rays.

In the present invention, the film having regular or irregular small holes is a synthetic resin film such as polyimide, polyester, polyethylene terephthalate, aluminum, nickel, stainless steel, or iron.

Metal films such as palladium can be used alone or in a stacked manner. The film preferably has excellent heat resistance, solvent resistance, abrasion resistance, and mechanical strength.

Since the thickness of the film is related to the strength of the film and the amount of recording liquid discharged, it is necessary to appropriately determine the thickness according to the material of the film and the amount of recording liquid discharged.

A few microns depending on the processability of the film, the amount of recording liquid discharged, etc.
It is several hundred microns.

Further, the size of the minute hole can be appropriately selected depending on the amount of recording liquid discharged, but it is preferably several microns to several hundred microns depending on the recording liquid retention and discharge state.

If you make the holes too small, the amount of recording liquid ejected will be small.
If you cannot obtain the recording density of printed matter, and if you enlarge the hole,
The discharge amount is too large to pass through the formation of minute dots.

The shape of the hole is preferably circular in order to obtain circular dots, but the shape of the hole is not particularly limited. Also, even if it is a hole that goes through the film.

The side of the film facing the heat generating part may be a concave hole that does not pass through.

Further, the number of the minute holes can be increased or decreased depending on the printing density, etc., and the number is about 1 to 100 per ln+, depending on the size of the holes.

These minute holes may be arranged irregularly, but
Preferably, they are located in a regular array.

The heating part that generates heat according to the input signal is the same as the one commonly used for thermal recording.

Alternatively, it can be used after further processing.

In the present invention, many dyes and pigments can be effectively used as the colorant (A) in the recording liquid, either alone or in combination.

Dyes include direct dyes, acid dyes, and basic dyes.

These include mordant dyes, metal-containing dyes, vat dyes, sulfur dyes, 2 reactive dyes, 1 disperse dye, alcohol-soluble dyes, oil-soluble dyes, etc. In terms of chemical structure, they include acridine dyes, aniline black, anthraquinone, dyes, azine dye,
Azo dyes, azomethine dyes, benzo and naphthoquine dyes, indigoid dyes, indophenols, indoanilines, indamines, leuco vat dye esters, naphtholimide dyes, nigrosine and insulin, nitro and nitroso dyes, oxazine and dioxazine dyes, oxidative dyes, phthalocyanines dye, polymethine dye,
Quinophthalone dyes, sulfur dyes, tri- and diallylmethane dyes, thiazine dyes, thiazole dyes, xanthine dyes are usefully used.

Further, as the pigment, both organic pigments and inorganic pigments can be used.

Examples of organic pigments include nitroso-based, nitro-based, phthalocyanine-based, insoluble azo-based, poorly soluble azo-based, soluble azo-based,
Basic dye lake type, acid dye lake type.

Vat dye lake type, quinacridone type, dioxazine type,
Perylene-based, isoindolinone-based, etc. are preferably used.

As the inorganic pigment, carbon black, titanium white, cobalt oxide, barium sulfate, calcium carbonate, magnesium carbonate, navy blue, etc. are preferably used.

Note that 9. The colorant (A) is preferably dissolved in the monomer and/or prepolymer (B) or solvent (D), but 1. Some dyes or pigments such as disperse dyes are used as recording agents. in case of.

It is necessary to disperse the particles so that the particle size is at least smaller than the minute holes in the film. The particle size of the recording agent in such a dispersed state is several microns or less, preferably 1.0 microns or less.

Monomers and/or prepolymers (B) that can be cured by ultraviolet irradiation are known per se, and include crosslinking polymerization types containing unsaturated double bonds and ring-opening polymerization types containing epoxy groups. There is something.

As a crosslinking polymerization type monomer containing an unsaturated double bond,
Styrenes, alkyl (meth)acrylates, ethoxyglycol di(meth)acrylates.

Ethylene glycol mono(meth)acrylates.

Polyprolene glycol di(meth)acrylates.

Polyethylene glycol mono (meth)acrylates, 1,6-hexanethiol di(meth)acrylate-t-
, 1,6-hexanediol mono (meth)acrylate, trimethylolpropane tri(meth)acrylate, etc. Similarly, examples of prepolymers include (meth)acrylates such as epoxy resins and polyesters, and isocyanate group-containing resins. Examples include reactants with hydroxyl group-containing unsaturated materials.

Ring-opening polymerization type compounds containing epoxy groups include bisphenol A diglycidyl ether, polyglycidyl ether of polyhydric alcohol, propylene oxide, butylene oxide, cyclic ethers, and lactones.

As the photopolymerization initiator (C), in the case of a cross-linked polymerization type containing an unsaturated double bond, such as benzoin and its derivatives, benzophenone and its derivatives, acetophenone and its derivatives, etc., which are known per se, can be used. There are things that generate radicals.

In the case of a ring-opening polymerization type, examples include those that generate a Lewis acid upon irradiation with ultraviolet light, such as onium salts of Lewis acids.

Examples of the solvent (D) used as necessary include water and organic solvents. Examples of the organic solvent include alcoholic solvents 9 such as methanol, ethanol, n-propyl alcohol, and isopropyl alcohol.

n-butyl alcohol, 5ec-butyl alcohol.

terL-7' tyl alcohol, isobutyl alcohol.

Pentyl alcohol, hexyl alcohol, heptyl alcohol, octyl alcohol, nonyl alcohol, decyl alcohol, diacetone alcohol, etc.

Ether solvent 2 For example, ethyl ether, butyl ether, ethylene glycol diethyl ether.

Glycol solvents 2, such as ethylene glycol monoethyl ether, diethylene glycol monobutyl ether, ethylene glycol monobutyl ether, etc. 2 For example, ethylene glycol, propylene glycol.

Butylene glycol, hexylene glycol, triethylene glycol, triethylene glycol, polypropylene glycol, methoxy glycol, ethoxy glycol, polyethylene glycol, glycerin, ketone solvents 2 Ester solvents such as acetone, methyl ethyl ketone, isobutyl ketone, cyclohexane, etc. , ethyl acetate, proyl acetate, phthyl acetate, ethyl formate, ethylene glycol monoethyl ether acetate, phenyl acetate, etc., hydrocarbon solvents 1 For example, hexane, octane, cyclohexane, toluene, xylene, petroleum-based hydrocarbon solvents, halogenated carbonized Hydrogen Solvent 2 For example, carbon tetrachloride, dichloromethane, trichloroethylene, tetrachloroethane, dichlorobenzene, etc.

Further, N-methyl-2-pyrrolidone, monoethanolamine, jetanolamine, morpholine, etc. can be used. These solvents are soluble in dyes.

Taking into consideration the dispersibility of dyes and pigments, as well as appropriate adjustment of the boiling point, surface tension, etc. of the recording liquid, it is possible to use one or more of them within a range that does not impair the desirable characteristics of the recording liquid. can.

The recording liquid described above preferably contains a component that vaporizes when heated, and from this point of view it is generally necessary to add one or more monomers or solvents having a boiling point of 150° C. or lower.

Various additives can be appropriately added to the recording liquid in the present invention depending on the purpose.

As the viscosity regulator, methylcellulose, hydroxypropylcellulose, carboxymethylcellulose, polyvinyl alcohol, polyvinylpyrrolidone, gum arabic, starch, sodium alginate, etc. are preferably used.

As the surface tension adjusting agent, anionic, cationic, or ionic activators can be used, and the amount of these activators is 10% by weight or less, preferably 1% by weight based on the recording liquid.
The amount used below is sufficient.

Also, to ensure stable dispersion of the recording agent.

The above-mentioned activators can be used as dispersants.

Pigment dispersants made of various pigment derivatives known in the pigment field can also be used.

Further, in order to maintain stable solubility of the dye, urea or a nitrogen-containing compound may be added.

Also, dimethylammonium chloride, alkylbenzyl, laurylamine acetate, N-alkyltrimethylenediamine, 2-bromonitropropane-1,3-
Diols, benzotriazoles, etc. can also be added as stabilizers.

The pH adjuster is added as necessary to increase the solubility of the recording material, to maintain stability, to adjust the hue, or to prevent changes in the physical properties of the solvent.

Examples of the PH3 regulator include sodium hydroxide, potassium hydroxide, ammonium hydroxide, lower alkanolamine, sodium phosphate, and sodium carbonate.

In addition, fluorescent dyes, infrared absorbers, fragrances, antifungal agents, bactericides, chelating agents, antioxidants, silane coupling agents, plasticizers, thermoplastics, etc. are used to impart recording liquid uses and resistance. Resins and the like can also be added.

In the present invention, ultraviolet rays are irradiated by means known per se, but if the recording liquid contains a low-volatility solvent, it is removed by (hot) air or the like during or before or after the ultraviolet irradiation. Sometimes the need arises.

In the present invention, the surface of the recording medium is subjected to physical treatment such as corona discharge treatment in order to improve adhesion with the recording liquid.
It is also a preferred embodiment to apply a chemical treatment such as an anchoring agent.

The present invention will be explained in detail below using examples.

Example 1 20 micron thick polyimide film (1).

10 holes (2) with a diameter of 30 microns per square crane
Fixed.

The following recording liquid (3) was applied to the surface of the polyimide film (1) by penetrating the felt (4), and the following recording liquid was uniformly supplied into the holes.

The film supplied with the recording liquid was moved over a heat generating head (5) that generates heat in response to an input signal.

In response to the heat generating head, the recording liquid is ejected and flies onto the polyester film (6), which is disposed on the side facing the heat generating head and whose surface is subjected to corona discharge treatment, to form an image, and after being cured by irradiating ultraviolet rays, Volatile components were removed by hot air. This cured image had excellent solvent resistance.

A similar image could also be obtained in a method in which the polyimide film with holes was fixed and the Rad portion was moved for one heat generation.

Recording liquid formulation (Recording liquid 1) Oil black HBB 6 parts by weight Ethylene glycol diacrylate 30 Hydroxypropyl cellulose 2 Isopropyl alcohol
40 ethylene glycol 10 benzoin ethyl ether 2 (recording liquid 2) Food red No. 3 7 ethylene glycol diacrylate 18 ethylene glycol
10 Anionic surfactant 5
Benzoin ethyl ether 1.2 Purified water
45 (Recording liquid 3) Phthalocyanine blue 4 bisphenol A diglycidyl ether propylene oidide
10 Methyl ethyl ketone 2
0 Aromatic diazonium salt of Lewis acid 1 (PP-3
3. Manufactured by Asahi Denka Kogyo ■, trade name) (Production method of recording liquid) In recording liquids 1 and 2, after dissolving the dye, pressure filtration was performed using a 3 micron filter.

Recording liquid 3 was dispersed using an attritor and filtered under pressure using a 10 micron filter.

Example 2 15 micron thick nickel foil with 3 diameters per 1fi square
Example 1 except that a film with 0 micron holes (100) was used, the following recording liquid was used, and hot air was not applied.
An image with excellent solvent resistance was obtained in the same manner as above.

(Recording liquid 4) Carbon black 12 parts by weight Navy blue
11.6-hexanediol diacrylate 30 styrene
40 dioctyl phthalate
5 Benzophenone 2 Bisdiethylaminobenzophenone 3 (Production method of recording liquid) Same as recording liquid 3.

〔Effect of the invention〕

According to the present invention, the generation of bubbles during the supply of recording liquid and the resulting printing defects, which have been problems with inkjet, do not occur, and the image is cured by ultraviolet irradiation.
It has become possible to perform printing with excellent solvent resistance, and it has also become possible to print on non-absorbent recording materials.

[Brief explanation of the drawing]

1 is a plan view of the film, FIG. 2 is a perspective view showing the recording method, and FIG. 3 is a sectional view showing the recording principle. The symbols in FIG. 9 are as follows. 1...Film, 2...Minute hole. 3...Recording liquid, 3a...Bubble. 4...Felt, 5...Heating head. 6... Recording paper

Claims (1)

[Claims] 1. Apply recording liquid to a film that has minute holes regularly or irregularly, and after supplying the recording liquid to the holes, bring a heat generating part that generates heat according to an input signal into contact with the holes. A recording method in which recording is performed by heating the recording liquid in the film and ejecting the recording liquid onto the recording medium from minute holes in the film using energy from thermal expansion of the recording liquid or vaporization of the recording liquid due to the heating. The recording liquid includes a colorant (A) such as a dye or pigment, a monomer that can be cured by ultraviolet irradiation, and/or a prepolymer (
B), a photopolymerization initiator (C), and if necessary a solvent (D
), and the recording method is characterized in that after recording, the recording liquid on the recording medium is irradiated with ultraviolet rays.