JP2002248789A - Ink jet recorder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem of vaporization of a solvent such as a water contained in an ink in a tube through the tube in a method of supplying ink by using the tube so that the viscosity of the ink is possibly raised and a pigment in the ink is possibly stuck therein, thereby causing a trouble in supplying and ejection of ink. SOLUTION: In order to prevent a solvent such as a water from being vaporized from the tubes for conveying the ink from ink tanks 11, 12, 13, 14 to a print head 4, the tubes are wrapped with ink (dye ink) of which the raising of the viscosity and sticking due to vaporization of the solvent such as the water is hardly created or glycerin, diethylene glycol triethylene glycol, or mixture of them which is hardly vaporized. The ink of which the raising of the viscosity and sticking is hardly created or the solvent which is hardly vaporized is wrapped with a tube 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording apparatus for performing recording by ejecting ink droplets from an ejection nozzle onto recording paper at a high speed.

[0002]

2. Description of the Related Art In an ink jet printer recording apparatus, small droplets of ink are caused to fly according to various working principles, and the ink droplets are adhered to a recording material such as paper to perform recording. In general, such an ink jet recording type apparatus generally includes a recording unit (print head) for forming ink droplets, an ink supply unit for supplying ink to the recording unit, and ink discharged from the print head except during a recording operation. Recovery processing means,
And a clogging recovery processing means for eliminating clogging of the ejection nozzles and ink flow paths of the print head.

Various proposals have been made for supply means for supplying ink to the recording means (print head). For example, according to an ink supply unit of a printing apparatus described in Japanese Patent Publication No. 5-218 or the like, ink filled in an ink cartridge is supplied to a recording unit (recording head) mounted on a carriage using an ink supply tube. Supplied to

[0004]

However, in the above-described ink supply method using a tube, the solvent such as water contained in the ink communicating with the inside of the tube evaporates to the outside through the tube, and as a result, the remaining In addition, there has been a problem that the viscosity of the ink becomes high, which hinders the supply of the ink, and that the dye or solid contained in the ink adheres to the inner surface of the tube, thereby causing non-discharge.

[0005] This case is more remarkable when a pigment-based ink is used than when a dye-based ink is used. This is due to the difference in the pigment, the pigment is usually larger in particle size than the dye, and the solubility in water is low, so the pigment is more easily precipitated by evaporation of the water contained in the ink, It is easy to stick to the inside of the tube.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems. An ink supply means using one or more tubes is provided with an evaporation preventing means for preventing evaporation of water in the ink. It is an object of the present invention to provide a highly reliable ink jet recording apparatus capable of efficiently supplying ink while minimizing evaporation of a solvent such as moisture.

[0007]

Therefore, in the present invention, an object of the present invention is to provide an ink jet recording apparatus described in any one of the following items (1) to (3) to achieve the above object. It is.

(1) Recording means (print head) for forming ink droplets, carriage means for moving the recording means, cap means for capping the recording means, and supply to the recording means An ink tank that stores ink to be printed, an ink supply unit that uses one or more tubes in an ink path that connects the ink tank to the recording unit, and an ink supply unit that supplies ink from the ink tank to the recording unit. Pump means acting on the recording means via the cap for pumping ink;
An ink jet recording apparatus comprising: an ink supply unit using one or more tubes; and an evaporation preventing unit that prevents evaporation of moisture in the ink that is communicated with the ink supply unit.

(2) The ink supply means prevents evaporation of water (solvent) contained in the ink passing through the tube, prevents an increase in the viscosity of the ink, and prevents fixation of a dye or a solute in the ink.
In addition, the outside of the tube communicating with the pigment-based ink, in which the viscosity of the ink is likely to increase and fix, is covered with the dye-based ink, which is less likely to increase in viscosity and fix than the pigment-based ink, as evaporation preventing means. The ink jet recording apparatus according to the above (1), having a double tube structure in which the ink is wrapped in a tube.

(3) The evaporation preventing means is a solvent other than the dye-based ink, such as glycerin, diethylene glycol, triethylene glycol, or a mixture thereof, which hardly evaporates and does not react with the material of the tube. The inkjet recording apparatus according to the above (1) or (2).

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings.

FIG. 1 illustrates a basic ink jet recording apparatus of the present invention.

FIG. 1 shows ink tanks 11, 12, 13,
The tube 3 for supplying ink from 14 to the print head 4 is shown. The ink tanks 11, 12, and 13 store dye-based color ink, and the ink tank 14 stores pigment-based black ink.
Tubes e, f, and g are connected to 1, 12, and 13, and a trifurcated tube h is connected to the ink tank.

These tubes e, f, g and h are:
At the seal portion S1, they are put together in one guide tube 3, and are separated as before at the seal portion S2 and connected to the respective printing sub-tanks of the print head 4.

Incidentally, the seal portion S1 is provided with the ink tank 11,
12, 13, and 14, the seal portion S2 is attached to the print head 4,
It is provided as close as possible (FIGS. 1, 3, and 5).
reference).

Reference numeral 2 denotes a carriage for moving the print head 4, and reference numerals 21 and 22 denote sliding shafts for guiding the carriage 2.

5 is a cap as a capping means, 6
Denotes a suction tube, and 7 denotes a pump as a pump means.

The ink contains a cap 5 and a suction tube 6
Is supplied to the print head 4 from the ink tanks 11, 12, 13, and 14 through the tube 3 by rotation of the pump 7 acting on the print head 4 via.

In accordance with the reciprocating movement of the carriage 2 having the print head 4 on the slide shafts 21 and 22, ink is ejected from the print head 4 and printing is performed.

(First Embodiment) Next, a first embodiment of the present invention will be described with reference to FIGS.

FIG. 2 is a view best showing the features of the present invention, and is a cut-away view of a tube 3 serving as an ink supply path from an ink tank to a print head.

A, b, c, and d are inks of each color pumped from the ink tank. d is a black pigment ink, and a to c are cyan, magenta and yellow dye inks.

Generally, pigment-based inks have a larger particle size and lower solubility in water than dye-based inks, so that pigments are more likely to be precipitated more remarkably by evaporation of water contained in the ink. It is also in a state where it is easily fixed to the inside.

F and g are tubes for communicating dye-based color inks, and e is the outer tube 3 as it is. This allows the dye-based ink communicating with the inside of the tube e to function as evaporation prevention means.

Reference numeral h denotes a tube for communicating the pigment-based black ink.

According to the above-described structure, the viscosity of the ink is hardly increased due to the evaporation of the solvent such as the water outside the tube h which communicates the pigment-based ink, which is likely to increase the viscosity of the ink due to the evaporation of the solvent such as the water. A double tube structure is formed, which is wrapped in color ink and further covered with a guide tube e. This kind of double structure plays a role of preventing evaporation of a solvent such as water contained in the pigment ink d.

Further, when the length of the tube 3 which is in direct contact with the atmosphere and through which the dye-based ink communicates is made as short as possible, evaporation of a solvent such as moisture in the ink can be suppressed.

Next, an example of the periphery of the seal portion S1 of the tube of the first embodiment will be described with reference to FIG.

As shown in FIG. 3, in the guide tube e,
As a means for preventing evaporation of water (solvent), one tube h for passing the pigment-based ink and two tubes f and g for passing the dye-based ink are inserted together through the dye-based ink a. The dye-based ink a as a means for preventing evaporation of water (solvent) is also one of cyan, magenta, and yellow printing color inks.

In the vicinity of the seal portion S2, on the contrary, a tube h through which the pigment-based ink passes from the guide tube e.
One tube and two tubes f and g through which the dye-based ink passes are separated, and return to each of the four tubes including the tube e.

(Second Embodiment) Next, a second embodiment of the ink jet recording apparatus of the present invention will be described with reference to FIGS.

FIG. 4 is a cross-sectional view of the tube 3 serving as an ink supply path from the ink tank to the print head.

P is an ink tube for communicating pigment-based ink, and q, r, and s are ink tubes for communicating dye-based ink.

T denotes a liquid which is difficult to evaporate, and the ink tube in the tube 3 through which the tube p of the pigment-based ink and the ink tubes q, r, and s through which other dye-based inks pass can be inserted collectively. p, q,
r, s, each ink tube p, q,
The tube 3 surrounding r and s forms a kind of double structure.

The liquid T may not be a dye-based ink, but may be a liquid that hardly evaporates near room temperature and does not cause a chemical reaction with the tube material, such as glycerin, diethylene glycol, triethylene glycol, or a mixture thereof. .

Next, an example of the periphery of the seal portion of the tube according to the second embodiment will be described with reference to FIG.

As shown in FIG. 5, inside the guide tube 3,
One tube p for passing pigment-based ink and tubes q, r, and s3 for passing dye-based ink with glycerin, diethylene glycol, triethylene glycol, or a mixture T thereof interposed therebetween as means for preventing evaporation of water (solvent).
The book is inserted all together.

In the vicinity of the seal portion S2, on the contrary, a tube p through which the pigment-based ink passes from the guide tube 3
One tube and three tubes q, r, and s through which the dye-based ink passes are separated and return to each of the four tubes.

As described above, the double tube structure prevents the solvent such as water in the ink from evaporating through the ink tube to a minimum, and does not cause the ink to thicken or fix the dye. Efficient ink supply can be performed.

[0040]

As is apparent from the above description, according to the present invention, the ink supply means using one or more tubes is provided with the evaporation prevention means for preventing the evaporation of the water in the ink. Evaporation of a solvent such as water in the ink through a tube that supplies the ink from the tank to the print head is suppressed, and an efficient ink supply can be performed, and a highly reliable ink jet recording apparatus can be obtained.

In addition, the outside of the ink tube is not a dye-based ink but a liquid which hardly evaporates at around room temperature, such as glycerin, diethylene glycol, triethylene glycol, or a mixture thereof, and does not cause a chemical reaction with the tube material. By covering, a solvent such as water in the ink is prevented from evaporating through the tube to a minimum, and an ink jet recording apparatus capable of efficiently supplying the ink without increasing the viscosity of the ink or fixing the dye is obtained. I can do it.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a general inkjet recording apparatus of the present invention.

FIG. 2 is a sectional view showing a tube according to the first embodiment of the present invention.

FIG. 3 is an explanatory view around the seal portion of the tube according to the first embodiment of the present invention.

FIG. 4 is a sectional view showing a tube according to a second embodiment of the present invention.

FIG. 5 is an explanatory diagram around a seal portion of a tube according to a second embodiment of the present invention.

[Explanation of symbols]

 2 Carriage 3 Tube 4 Print head 5 Cap 6 Suction tube 7 Pump 11, 12, 13 Dye-based ink tank 14 Pigment-based ink tank

Claims (3)

[Claims] 1. A recording means (print head) for forming ink droplets, a carriage means for moving the recording means, a cap means for capping the recording means, and a supply to the recording means. An ink tank for storing ink, an ink supply means using one or more tubes in an ink path for communicating the ink tank with the recording means, and an ink for supplying ink from the ink tank to the recording means. An ink-jet recording apparatus comprising: a pump that acts on the recording means via the cap that pumps the ink; and an evaporation prevention device that prevents evaporation of water in the ink that communicates with the ink supply means that uses the one or more tubes. An ink jet recording apparatus comprising: 2. The ink supply means prevents evaporation of water (solvent) contained in ink passing through a tube, prevents an increase in viscosity of the ink, a fixation of a dye or a solute in the ink, and increases the viscosity of the ink. The outside of the tube through which the pigment-based ink, which easily causes sticking, is covered with a dye-based ink, which is less likely to increase in viscosity and stick than the pigment-based ink, as evaporation prevention means, and the dye-based ink is wrapped in a tube. The ink jet recording apparatus according to claim 1, having a double tube structure. 3. The method according to claim 1, wherein the evaporation preventing means is a solvent other than the dye-based ink, such as glycerin, diethylene glycol, triethylene glycol, or a mixture thereof, which hardly evaporates and does not react with the material of the tube. Item 3. The ink jet recording apparatus according to item 1 or 2.