JP2000238279A - Ink cartridge - Google Patents

Abstract

PROBLEM TO BE SOLVED: To sustain the quality of ink suitable for printing by reducing the inner pressure to a specified level, hermetically sealing a bag of gas shielding film while ensuring a space, and housing an ink cartridge in a space of pressure lower than the reduced level thereby removing bubbles surely. SOLUTION: An elastic material 4 for absorbing and impregnating with ink is housed while being compressed in a housing chamber defined by partitioning a container 1 with a wall and a protrusion 10 for compressing the elastic material 4 is formed in the vicinity of an ink supply opening 5. A recess 12 forming a cavity is provided at the upper end of the protrusion 10 and a through hole 13 is extended therefrom to the supply opening 5. A packing 16 to be engaged with an ink supply needle of a recording head is then inserted into the outer end of the through hole 13 and sealed with a gas shielding film 17. A hole 8 communicating with the atmosphere and a groove 19 are made in the surface of a cover body 9 and covered by gas shielding films 20, 21 along with an ink ejection opening 7. After being ejected with ink, the container 1 is housed in a deaeration chamber and the inner pressure thereof is reduced to 0--300 mmHg. The gas shielding film 21 is provided with a stripping tongue 21a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink cartridge for an ink jet recording apparatus in which an ink jet recording head and an ink cartridge are mounted on a carriage and ink is supplied by replacing the cartridge.

[0002]

2. Description of the Related Art In an ink-jet printer of a type in which an ink container is mounted on a carriage having an ink-jet recording head, fluctuations in water head pressure due to ink swing due to movement of the carriage, and printing due to foaming. To prevent defects, the ink container is divided into two regions as described in European Patent Publication No. 581531, and a porous body is stored on the recording head side, and ink is stored in the other region. It has been proposed to do so. With such a structure, ink is supplied to the recording head through the porous body, so that inconvenience caused by the swing of the ink can be prevented.

[0003]

However, in the ink jet type recording apparatus, the pressure is reduced when the ink contains bubbles, because the ink in the pressure generating chamber is pressurized to generate ink droplets. Since the ejection performance of droplets is also reduced, some measures have been taken to prevent bubbles from being mixed in the step of injecting ink into the ink cartridge. For example, ink from which dissolved air has been eliminated is injected into a porous body, or injected under reduced pressure. On the other hand, at the time of use, the pressure was reduced for the purpose of keeping dissolved air excluded so that bubbles that entered when the ink cartridge was mounted or bubbles remaining in the recording head could be dissolved in the ink and eliminated. 2. Description of the Related Art Packaging in a metal container or packaging with an air-shielding film has been performed. However, if the pressure reduction value in the ink cartridge container is not optimized at the time of manufacturing and assembling the ink cartridge and thereafter, the bubbles remain in the ink cartridge and the ability to dissolve and remove the bubbles remaining in the recording head. It was found that the above-mentioned problems could not be sufficiently solved, such as lacking. The present invention has been made in view of such circumstances, and an object of the present invention is to provide an ink cartridge that can reliably remove ink bubbles and maintain ink at a quality suitable for printing. It is.

[0004]

According to the present invention, a porous body made of an elastic material suitable for absorbing ink is accommodated in the present invention, and is connected to an ink supply needle of a recording head. A container body provided with a matching ink supply port, an ink injection port for sealing the opening of the container body, and a lid having a recess forming a reduced pressure space;
The internal pressure is reduced to 0 to minus 300 mmHg, the space is secured in a bag made of an air-permeable film, and the bag is sealed and housed in a pressure space lower than the internal pressure.

[0005]

FIG. 1 and FIG. 2 show an embodiment of an ink cartridge, which is a container 1 formed by injection molding a substantially rectangular polymer material whose opening side is slightly divergent. Is divided into a plurality of ink storage chambers 3 by walls 2, and a porous body 4 made of an elastic material suitable for absorbing and impregnating ink is stored in each storage chamber 3 in a compressed state. Is formed with an ink supply port 5 which engages with the ink supply needle of the recording head. The opening 6 is sealed with a lid 9 having an ink injection hole 7 and an air communication hole 8.

A convex portion 10 for compressing the porous body 4 is formed in the vicinity of the ink supply port 5, and a concave portion 12 is formed at an upper end thereof to form a void 11 having a constant opening area. Through hole 13 extending from here to ink supply port 5
Are drilled. At the outer end of the through hole 13, a packing 16 is inserted, which is engaged with the ink supply needle of the recording head in a liquid-tight manner. It is sealed with an air-shielding film 17. In addition, the code | symbol 18 in a figure is
5 shows a filter material provided to cover the recess 12.

On the other hand, a meandering groove 19 having one end communicating with the atmosphere communication hole 8 and the other end extending to the other side of the lid 9 is formed on the surface of the lid 9 as shown in FIG. Thus, the first film 20 that is prevented from being inadvertently peeled off so as to cover the area indicated by hatching in the figure, and the second film 21 that can be easily peeled off by pulling up the tongue piece 21a
Is affixed. The films 20, 21 in the groove 19
The area which is not sealed is formed as a through hole in the lid 9.

FIG. 4 shows an embodiment of the ink injecting device. A receiving table 31 for holding a pallet 30 is configured to be vertically movable as shown by an arrow A by a driving mechanism (not shown). On the other hand, the base 32 has a through hole, the lower surface is formed by a step portion 33 on the peripheral surface of the pallet 30, the upper surface is formed by a lid 34 described later, and the injection chamber 35 is formed by the flow path 36 to the vacuum pump 37. It is connected.

The cover 34 has a through hole 38 formed in a region facing the injection chamber 35, and a piston member 39 which can move up and down as shown by an arrow B in the figure while maintaining an airtight state.
Is inserted.

The piston member 39 is connected to an injection needle 40 at a position facing the ink injection port 7 of the container 1 set in the injection chamber 35, and to an air supply device (not shown) so as to face the atmosphere communication port 8 of the container 1. It is provided with a flow path 41 that communicates. The injection needle 40 is connected to a branch pipe 44 via a flow path 42 and a tube 43.

In this embodiment, the gas-liquid separation unit 45 has an upper end and a lower end liquid-tightly fixed to a cylinder 47 so that the hollow fiber bundle 46 serves as a liquid flow path, and the cylinder 47 is connected to a vacuum pump 48. A negative pressure is applied to the outer periphery of the hollow fiber. One end of a cylinder 47 is connected to an ink tank 50 by a tube 49, and the other end is connected to a branch pipe 44 via a stop valve 51.

The measuring pipe 52 includes a cylinder 53 and a piston 5
The top dead center side is connected to the branch pipe 44 by a tube 55. In the drawing, reference numeral 56 denotes a stop valve, and 57 denotes a pump for pressure feeding ink.

When the pallet 30 on which the container 1 in which the components have been assembled by the above-described steps is placed reaches the ink injection device and is set below the injection chamber 35, the pedestal 31
Rises until it contacts the lower surface of the base 32.

Next, the piston member 39 is connected to the lid 9 of the container 1.
Is lowered to such an extent that a space can be secured between them, and the stop valve 56 is opened with the stop valve 51 communicating with the gas-liquid separation unit 45 closed, and the vacuum pump 37 is operated to operate the injection chamber 35. , The tube 43, and the measuring tube 52 are reduced to a predetermined pressure.

At the stage where the pressure has been reduced to a predetermined pressure, the stop valve 56 is closed, and the stop valve 51 is opened to inject a predetermined amount of the ink 7 into the measuring pipe 52. The member 39 is lowered to the bottom dead center. Thereby, the lower end 41a of the flow path 41 is connected to the atmosphere communication port 8, and the injection needle 40 enters from the ink injection port 7 to near the bottom surface of the container 1.

Next, with the stop valve 51 closed and shut off from the gas-liquid separation unit 45, the stop valve 56 is opened and the piston 54 of the measuring pipe 52 is pressed to discharge a predetermined amount of ink. A predetermined amount of ink is injected into the container 1.

At this time, since the ink which has been surely degassed by the gas-liquid separation unit 45 is injected into the porous body 4,
The ink easily dissolves the gas adsorbed in the pores of the porous body 4 that could not be exhausted in the above-described depressurization step, and generates bubbles in the porous body 4 without remaining. It is uniformly absorbed by the porous body 4.

At the stage when the ink injection is completed, the receiving table 31
The airtight film 20 cut to a size that covers the air communication port 8, the ink inlet 7, and the narrow groove 19 is adhered to form a capillary by the narrow groove 19 and the film 20. In this state, when the container 1 is housed in the degassing chamber and decompressed to about 200 mmHg, the container 1 is depressurized through the narrow groove 19 whose one end is still open. When a predetermined time has elapsed, the tongue piece 2 for peeling off
The container 1 is completely shielded from the atmosphere by adhering the air-shielding film 21 provided with 1a to the open area of the narrow groove 19.

When the pressure of the container 1 is reduced to a pressure lower than -300 mmHg, when small bubbles remain in the corners of the container 1, especially in the through holes 13, they expand due to the reduced pressure,
It has been found that the toner remains in the container as it is and hinders the printing operation. On the other hand, it was found that when the decompression value was increased beyond -300 mmHg, no bubbles remained or the size became invisible. That is, it is necessary to suppress the reduced pressure value to preferably -200 mmHg, and at least -300 mmHg.

On the other hand, in the ink cartridge bundled with the recording apparatus, it is necessary to fill the ink without leaving air bubbles in the flow path such as the pressure generating chamber of the recording head which is left in the atmosphere. At the time when the recording head is filled with the ink, as shown in FIG. 7, it is desirable that the pressure be lower than the reduced pressure value of the supply, and more preferably -200 mm.
Hg, more preferably below -250 mmHg.

By the way, a container made of a polymer material or the like and having a structure in which the lid 9 is adhered cannot be completely air-blocked. Then, the internal pressure in the container 1 gradually increases. Therefore, the container 1 in which the filling of the ink has been completed is a bag 60 made of an air-shielding film constituted as a laminated structure of a heat-sealable polymer material and a metal layer as shown in FIG. At a pressure lower than that of the container 1, for example,-
The pressure is reduced to 450 mmHg or less, and the opening is sealed by heat welding.

Between the bag 60 and the surface of the container 1, a lid 9
Since a decompressed space is secured by the concave portions 9a and gaps formed in the container 1, the negative pressure in this space acts on the container 1, and the internal pressure of the container 1 gradually decreases over time as shown in FIG. As a result, the ability to dissolve bubbles is improved, and the ink cartridge becomes more preferable. For example, Initial-2
What was not less than 00 mmHg was lowered to around -300 mmHg, and thereafter taken out of the bag 60 and
This internal pressure is maintained until 1 is peeled off.

As described above, the internal pressure is -300 mmH
By sealing with g or more, bubbles remaining in the container can be eliminated, or the size can be suppressed to a size that cannot be seen. On the other hand, if the airbag is housed in the bag 60 at a pressure lower than the internal pressure by about 150 mmHg or more, it is observed that the air bubbles disappear over time even if the air bubbles remain in the container. Further, it was confirmed by an experiment that the pressure in the container 1 also decreased with time as shown in FIG. As a result, the decompression pressure in the bag 60 is lower than the sealing pressure of the container 1 by about 150 mmHg or more, preferably -450 mmHg.
The pressure is preferably set to not more than mmHg.

In the ink cartridge bundled with the recording apparatus, the reduced pressure value is set lower than that of the supplies, and the reduced pressure value of the bag 60 is maintained at -450 mmHg or less, which is lower than that of the container. The internal pressure will be maintained at about -250 mmHg, which is also suitable for initial filling.

FIG. 7 shows the relationship between the internal pressure of the container and the success rate of the initial filling. When the internal filling pressure is lower than -240 mmHg, the filling can be surely completed by only one filling operation.

[0026]

As described above, in the present invention,
A container body containing a porous body made of an elastic material suitable for absorbing ink and having an ink supply port engaged with an ink supply needle of a recording head; and an ink for sealing an opening of the container body. Consists of an inlet and a lid provided with a concave part that secures a decompression space, and has an internal pressure of 0 to minus 300 mmHg.
The pressure is reduced and the air bag is sealed in a bag made of an air-tight film.The ink is housed in a pressure space lower than the inside of the container. It is possible to maintain the dissolved atmospheric pressure at or below the saturation value for a long period of time even after mounting on the recording head.

[Brief description of the drawings]

FIG. 1 is an assembled perspective view showing one embodiment of an ink cartridge of the present invention.

FIG. 2 is a sectional view showing an embodiment of the ink cartridge according to the present invention.

FIG. 3 is a top view illustrating a structure of a lid of the ink cartridge.

FIG. 4 is a configuration diagram illustrating an embodiment of an ink injection device.

FIG. 5 is a diagram showing a lapse of time of an internal pressure of a container.

FIGS. 6A and 6B are diagrams showing a packaging step, respectively.

FIG. 7 is a diagram showing the relationship between the internal pressure of the container and the success rate of initial filling of the recording head.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Container main body 4 Porous body 5 Ink supply port 7 Ink inlet 8 Air communication port 9 Lid 9a Depression for forming reduced pressure space 20, 21 Sealing film

Claims (3)

[Claims] 1. A container body containing a porous body made of an elastic material suitable for absorbing ink and provided with an ink supply port engaged with an ink supply needle of a recording head, and an opening in the container body. It consists of an ink inlet for sealing the part, and a lid with a concave part forming a decompressed space, the internal pressure is reduced to 0 to minus 300 mmHg, and the space is sealed in a bag made of an air-shielding film to secure An ink cartridge housed in a pressure space lower than the internal pressure. 2. The ink cartridge according to claim 1, wherein the internal pressure of the ink cartridge for initial filling is maintained at −250 mmHg or less at the start of use. 3. An initial internal pressure of the bag is minus 450 mm.
The ink cartridge according to claim 1, wherein the pressure is equal to or lower than Hg.