JPS58176277A - Recording liquid - Google Patents

Abstract

PURPOSE:To provide a recording liquid for a heat energy-utilizing ink jet recording device which reduces incidence of trouble in the recording head and insures printing with high reliability for a long period, prepared by adding a specified compd. (dye) as recording medium. CONSTITUTION:Used as recording medium is a compd. of formula I [where Q1 and Q2 are substd. phenyl or naphthyl group substituent being -OH, -SO3M, -Cl, -Br or -NH2; M is Na, K, Li, ammonium or amine)] (e.g. a compd. of formula II). The recording liquid is prepared by blending the above recording medium, a water-soluble organic solvent (e.g. alcohol, cyclic ether or alkylene glycol) used in about 5-95wt% of the total liquid and water.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a new recording solution suitable for an inkjet recording method in which a 1% recording liquid is discharged from fine discharge ports (discharge orifices) provided in a recording head, and recording is performed using the droplets. Regarding liquid.

BACKGROUND ART Writing instruments (fountain pens, felt-tip pens, etc.) for recording on recording materials such as paper have conventionally used inks prepared by dissolving various dyes in water or other organic solvents.

In addition, in the so-called inkjet recording method, in which recording is performed by ejecting the liquid in the recording head from the ejection orifice using vibrations by a piezo vibrator or electrostatic attraction due to the application of high voltage, various dyes are dissolved in water or organic solvents. It is known that compositions are used. However, compared to ink for stationery such as general fountain pens and felt-tip pens, inkjet recording liquids require more stringent conditions in terms of many characteristics.

The inkjet recording method does not generate noise and can perform high-speed recording or color recording on plain paper without special fixing treatment, and various types of inkjet recording methods are being actively researched.

In such an inkjet recording method, recording is performed by flying droplets (dropl·t) of a recording liquid called in-flow and adhering them to a recording material. The basic components of such a recording liquid include a recording agent (dye or pigment is used) and a liquid medium for dissolving or dispersing it (water or various organic solvent compositions or mixtures thereof are used), and as necessary. Each additive is added accordingly.

There are several types of such recording methods, depending on the method of generating droplets and the method of controlling the flight direction of the droplets. An example of this is shown in FIG.

Namely, number one! ! ! ! The apparatus No. 1 applies a recording signal to a recording head section having a piezo vibrator, and performs recording by generating droplets of recording liquid in response to the signal. In FIG. 1, l is a recording head, which includes two piezo vibrators and a diaphragm 2b.
, a recording liquid inlet 3, a liquid chamber 4 in the head, and an ejection port (ejection orifice) 5. A recording liquid 7 stored in a storage tank 6 is introduced into the liquid chamber 4 through a supply pipe 8 . In some cases, an intermediate treatment means 9 such as a pump or a filter may be provided in the middle of the supply pipe 8. Then, a signal converted from the recording signal 8 into a pulse by the signal processing means (for example, pulse conversion@) 10 is applied to the piezo vibrator 2a, and a pressure change occurs in the recording liquid in the liquid chamber 4 in accordance with the signal. . As a result, the recording liquid is discharged from the discharge orifice 5 in the form of droplets 11, and recording is performed on the surface of the recording material 12.

In addition to the above devices, various types of devices are known. For example, as shown in FIG. 2, as a modification of FIG. There is a piezoelectric vibrator device (the mechanism of droplet generation in this device is essentially the same as the device shown in FIG. 1). Also, there is a device that continuously generates charged droplets and uses a part of the droplets for recording, or a recording spatula.
There is also known a device that applies thermal energy corresponding to a recording signal to a recording liquid in a chamber of a computer, and generates droplets using the energy.

An example thereof is shown in Fig. 3-a, Fig. 3-bllff, and Fig. 4.

The head 13 is made of glass, ceramic, plastic plate, etc. having a hole 14 through which ink passes, and a heat generating head 15 used for thermal recording (a thin film head is shown in the figure, but is not limited to this). Obtained by gluing. The heating head 15 includes a haze-retaining film 16 made of silicon oxide or the like, aluminum electrodes 17-1, 17-2, a heating resistor layer 18 made of nichrome or the like, a heat storage layer 19, and a substrate with good heat dissipation such as alumina. It consists of 20 pieces.

The ink 21 has reached the discharge orifice 22, and the pressure P
A meniscus 23 is formed by this.

Now, when an electric signal is applied to the electric @17-1 and 17-2, the part of the heating head 15 shown in the diagram suddenly generates heat, bubbles are generated in the ink 21 that is in contact with this part, and the pressure causes the meniscus to form. 23 is ejected, the ink 21 is ejected from the orifice 22, becomes a recording droplet 24, and flies toward the recording target 25. FIG. 4 shows an external view of a multi-head in which a large number of heads shown in FIG. 3-a are arranged. The multi-head is made by bonding a glass plate 27 having multi-grooves 26 and a heat generating head 28 similar to that shown in FIG. 3-a.

In particular, in the liquid jet recording method that uses thermal energy, it is necessary to record high-resolution, high-quality ms at higher speed for a longer period of time, or to dramatically improve the service life of the device. Repeated use life (endurance life) of the head
need to be improved.

Factors that determine the service life of a recording head applied to the above-described recording method include the life of the heat-generating head provided therein, as well as the deposition of solid matter on its surface. Since the recording liquid is exposed to high temperatures during the repeated generation and disappearance of bubbles, it is expected that the thermally unstable recording liquid will undergo chemical changes. In fact, if the generation and disappearance of bubbles continues for a long time, as a result, near the surface of the heating head,
It has been experienced and observed in many experiments that the formation and deposition of insoluble matter causes the head to become unable to eject.

The object of the present invention is to provide a recording liquid that can significantly extend the life of the head, significantly reduce the failure rate of the head, and increase its reliability.

The recording liquid of the present invention that achieves the above object contains a metal compound represented by the following general formula (however, Cr,
The recording material contains a metal complex (dye) of On, Ni, or Co as a recording agent.

(However, in the above formula, Qlg Ql represents a substituted phenyl group or a substituted 7-tyl group, and the substituents at that time are OH, 803M, NOI, C/,
Fk.

-NH.

Incidentally, in the above formula and above, M is one selected from Ha, Ll, ammoniums, and amines. ) The recording agent of the present invention described above particularly has an azo bond and -C-S- which are formed when heated to 250°C or higher.

-0=Even upon cleavage of N-bonds, the decomposition products have sufficient solubility in the liquid medium.

Therefore, even when bubbles are repeatedly generated and extinguished over a long period of time, no insoluble matter is generated or deposited on the surface of the heat generating head, and the recording head does not become incapable of ejecting. or,
As predicted from its molecular structure, the dye used as the recording agent of the present invention has sufficiently satisfactory solubility in liquid media, and is particularly excellent in solubility in water, so it is suitable for aqueous recording. Composing the liquid: .

It can sometimes be used very effectively.

Further, the recording liquid of the present invention contains water, water, and dye in addition to the recording agent.
By adding and blending a suitable solvent such as an organic solvent and further additives such as a surface tension modifier and a viscosity modifier as necessary, a liquid composition called an ink can be obtained.

If this recording liquid is used for recording with a recording head like the one shown in Figure 1, the usable life of the recording head will be longer than that when a conventional recording liquid is used, as shown in the following example. It improved dramatically.

Specifically, the recording agent used in the present invention is a metal complex of a compound having the following chemical structure (however, the metal is Cr, O
n, Ni, O.).

(A3) (A4) (A5) (A6) (411) (A14) (A15) (Al1) (A17) (A19) (421) (A24) [R=-〇LO lock H] (A25) Note that water or a mixture of water and various water-soluble organic solvents is used as a liquid medium component for forming the V-needle solution of the present invention. Examples of water-soluble organic solvents include methyl alcohol, ethyl alcohol, 1-propyl alcohol, isopropyl alcohol, turtle-butyl alcohol, 5ee-butyl alcohol, t@rt-butyl alcohol, and isobutyl alcohol. Alkyl/alcohol-Δ/types having 1 to 4 carbon atoms such as alcohols; amides such as dimethylformamide and dimethylacetamide; acetone;
Ketones or ketone/alcohols such as diacetone/alcohol; ethers such as detrahydrofuran and dioxane; N-methyl-2-pyrrolidone, 1.3 dimethyl-2
-Nitrogen-containing heterocyclic ketones such as imidazolidinone; polyalkylene glycols such as polyethylene glycol and polypropylene glycol; ethylene glycol, propylene glycol, butylene glycol, triethylene glycol, 1,2.6 hexanetriol, thio Alkylene glycols in which the alkylene group has 2 to 6 carbon atoms, such as diglycol, hexylene glycol, diethylene glycol; glycerin; ethylene glycol methyl ether, diethylene glycol methyl (or ethyl) ether, triethylene glycol monomethyl (or ethyl) ether and lower alkyl ethers of polyhydric alcohols.

Among these many water-soluble organic solvents, the polyhydric alcohol diethylene glycol and the lower alkyl ether of the polyhydric alcohol triethyleneglyfur monomethyl (
or ethyl) ether, etc. are preferred wood.

The content of the water-soluble organic solvent in the recording liquid is generally within the range of 5 to 95% by weight, preferably 10 to 80%, and more preferably 20 to 50% based on the total weight of the recording liquid. Ru.

The recording liquid of the present invention prepared from such components can be used as a recording liquid for writing instruments or a recording liquid for so-called inkjet recording, and has its own recording properties (signal response, droplet formation stability, ejection stability, etc.). long-term continuous recording performance, ejection stability after long-term recording interruption) storage stability, dissolution stability of recording material,
Fixability to recording material or light resistance of recorded images.

Weather resistance, water resistance, alcohol resistance, etc. are all well-balanced and excellent. In order to further improve such properties, various conventionally known additives may be further added. Examples: viscosity modifiers such as EVA, polyvinyl alcohol, celluloses, water-soluble resins; cations. , various anionic or nonionic surfactants, surface tension regulators such as jetanolamine and silyethanolamine; pH regulators using buffering agents, and the like.

In order to prepare the recording liquid used in the type of recording method that charges the recording liquid, lithium chloride, ammonium chloride,
Resistivity modifiers such as inorganic salts such as sodium chloride are used. Further, urea and thiourea are preferably used as water retention improvers at the tip of the discharge orifice. In addition, in the case of a type that discharges recording liquid by the action of thermal energy,
Thermal physical property values (eg, specific heat, coefficient of thermal expansion, thermal conductivity, etc.) may be adjusted.

It is necessary to use the recording liquid of the present invention as a recording liquid for so-called writing instruments.

The invention will be explained in more detail in the following examples.

Example 1 A 510W layer (lower layer) was formed on an alumina substrate by sputtering to a thickness of 5 μm, and then a H1 layer was formed as a heating resistance layer.
The island is 1000A thick and the aluminum electrode is 300A.
After laminating to 0A thickness, selective etching is performed for 50μs.
A heating resistor pattern of a x 200 μm was formed.

Next, the layer 81 was laminated to a thickness of 3,500 layers as a protective layer (upper layer) by sputtering to form an electrical/thermal converter on the substrate, and then grooves with a diameter of 5 μm and a depth of 50 μm were carved. The glass plate was joined so that the groove and the heating resistor matched.

Subsequently, the distance between the tip of the heating resistor and the oriice is 25
A recording head was prepared by polishing the orifice end face to 0 μm. Using this recording head, ink having the liquid composition shown below was ejected.

In this case, the recording head is driven at 10μ-@c.

When a 40 mm rectangular voltage pulse printing signal was applied at a cycle of 200 μm IC, it had a lifespan sufficient to withstand 140 hours of continuous printing.

Example 2 Of the inks with the liquid composition used in Example 1, structural formula A
The table below shows the durability time of the recording head when various dyes listed in the table below were used instead of the copper complex dye in No. 2.

The head was driven at 10 μs@e with a 50 V rectangular voltage pulse printing signal at a cycle of 200 μm.Example 3 N-methyl-2-pyrrolidone of the ink composition used in Example 1 was used. The same results as in Example 1 were obtained when silyethanolamine was used instead.

Practical Example 4 Even when ethylene glycol was used in place of diethylene glycol in each of the ink compositions used in Example 2, the same results as in Example 2 were obtained.

[Brief explanation of the drawing]

FIGS. 1 and 2 are schematic diagrams of an Infusiera F recording device, respectively. 3-a and 3-b are a vertical sectional view and a horizontal sectional view of a main part of another recording device. FIG. 4 is an external perspective view of a multi-head head shown in FIGS. 3-a and 3-bf; ij. However, in the figure, 1...recording head, 2m...piezo vibrator 111 element, 2
b...Vibration plate, 3...Inflow port, 4...Liquid chamber, 5...
・Discharge orifice, 6. Storage tank, 7. Mackerel liquid, s. Supply pipe, 9. Intermediate treatment means, io...
Signal processing means. 11...Droplet, 12.25...Recording material, S...
Recording signal, 14...Liquid chamber, 15...Heating head, 1
6... Protective layer, 17. Electrode, 1g... Heat generating resistor layer, 19... Heat storage layer, 20... Substrate, 26.-Groove. Patent applicant: Canon Co., Ltd. Representative: Gi Marushima −Light 7″′
! 11,・°] C speed diagram 4

Claims (1)

[Claims] A recording agent that forms a recording medium contains a metal complex of a compound represented by the following general formula (provided that any metal of Or, On, Ni, or Co) is used as a recording agent. recording liquid. (However, in the above formula, e Q+ p Qt represents a substituted Fe2 group or a substituted naphthyl group, and the substituents at that time are -OH, 505M, NOx, CI
, Br. -Su! At least one selected from the following. In addition, in the above formula and above, M is Na, K, Li,
A type selected from ammoniums and amines)