JP2001105618A - Ink cartridge, production method thereof and ink jet recording apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve the simplification of a manufacturing process and to prevent the deterioration of a degassing degree. SOLUTION: An ink cartridge is equipped with an ink chamber 2 packed with foam 8, lids 12a, 12b having an ink injection hole 4, a vacuum hole 3 and an atmosphere communication hole 5 formed thereto and the seal member 7 for sealing the atmosphere communication hole 5 and elastomers 6 are inserted in the ink injection hole 4 and the vacuum hole 3 and the seal member 7a comprises an air and steam impermeable material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink cartridge, a method of manufacturing the same, and an ink jet recording apparatus suitable for simplifying the manufacturing process and preventing deterioration of the degree of degassing.

[0002]

2. Description of the Related Art An ink jet recording apparatus forms an image by applying a pressure to a plurality of ink chambers arranged in a print head in response to an electric signal and discharging ink from nozzles communicating with the ink chamber. .

As a method of applying pressure to the ink chamber, there are a method of generating a change in volume of the ink chamber using a piezoelectric element, a method of heating ink using a heating element, and generating bubbles.

In such a recording method, when air is mixed in an ink path such as a chamber of a print head, the ejection pressure becomes insufficient, which causes ejection failure or missing dots, thereby reducing the reliability of the ink jet recording apparatus. May cause a decrease.

In particular, when exchanging an ink cartridge, a large amount of air is mixed into the head, so that a recovery operation may take a long time or a large amount of ink may be wasted. Therefore, it has been conventionally known to use degassed ink to suppress the influence of air mixed in the ink path of the print head. By using degassing ink,
Air bubbles remaining in the print head can be dissolved in the ink, and the reliability of the ink jet recording apparatus can be improved.

Here, the ink cartridge has an injection hole for filling the ink and an air communication hole for preventing the negative pressure generated when the ink is reduced from being generated. Further, in order to maintain the degree of deaeration of the ink, a decompression process in the ink cartridge is performed.

However, the greater the degree of pressure reduction, the more easily the ink leaks from the injection hole or the air communication hole. In particular, this phenomenon becomes remarkable with respect to impact and temperature change.

For this purpose, as described in Japanese Patent Application Laid-Open No. Hei 7-132611, the injection hole and the air communication hole are sealed with a film having reduced water vapor permeability and gas permeability, so that the entire cartridge is formed. There has been proposed a method of packaging in an airtight container under reduced pressure.

[0009]

However, the above-mentioned prior art method has the following problems.

First, an ink injection step (under reduced pressure),
The sealing step (under atmospheric pressure), the re-deaeration step (under reduced pressure), and the cartridge manufacturing step are complicated. This is because although the ink injection is performed under reduced pressure, the subsequent sealing step is performed under atmospheric pressure, so that it is necessary to degas again. Incidentally, the reason why a film having gas permeability and not having water vapor permeability is used as the sealing material is to perform degassing again.

Second, the degree of deaeration is increased. This is because the degassed ink comes into contact with the air when the air is released to the atmosphere in the sealing step, and the degree of degassing deteriorates. Generally, it is difficult to deaerate ink by a decompression method. By the way, according to the deaeration method using the hollow fiber membrane, a predetermined degree of deaeration can be obtained. Further, by packaging under reduced pressure, it is possible to prevent the deterioration of the degree of deaeration, but it is difficult to restore the deteriorated degree of deaeration.

The present invention has been made in view of such a situation, and an ink cartridge, a method of manufacturing the same, and an ink jet recording apparatus capable of simplifying a manufacturing process and preventing deterioration of a degassing degree. That can be provided.

[0013]

According to a first aspect of the present invention, there is provided an ink cartridge comprising: an ink chamber filled with a foam; a lid formed with an ink injection hole, a pressure reduction hole, and an air communication hole;
A sealing member that seals the atmosphere communication hole, an elastic body is inserted into the ink injection hole and the pressure reducing hole, and the sealing member is made of a material having no gas permeability and water vapor permeability. It is characterized by. Further, the pressure reducing hole can be shared with the ink injection hole. Further, the sealing member may be made of a peelable material. The method of manufacturing an ink cartridge according to claim 4, wherein the ink cartridge body has a pressure reducing hole, an ink injection hole, and an air communication hole with respect to the ink cartridge body.
A first step of attaching a lid having an elastic body inserted into the pressure reducing hole and the ink injection hole; a second step of inserting an ink injection needle into the ink injection hole so as to penetrate the elastic body; A third step of inserting the ink cartridge so as to penetrate the elastic body, a fourth step of housing the ink cartridge main body in the decompression chamber, and setting the ink chamber of the ink cartridge main body in a decompressed state through the decompression needle through the decompression hole. A fifth step of performing deaeration of undegassed ink in the ink tank by a deaeration processing unit, and a seventh step of injecting the degassed ink from an ink injection hole through an ink injection needle. And an eighth step of retracting the decompression needle and the ink injection needle after the ink is injected, and closing the decompression hole and the ink injection hole by the restoring force of the elastic body. It is characterized in. The first and second steps include a ninth step of sealing the air communication hole with a sealing member made of a material having no gas permeability and water vapor permeability. be able to. In the seventh step, the degree of vacuum in the decompression chamber is set to 1
A tenth step at 60 Torr or less can be included. In the second and third steps, an eleventh step of sharing the pressure reducing hole with the ink injection hole and inserting an ink injection needle serving also as a pressure reducing needle into the ink injection hole so as to penetrate the elastic body is provided. The fifth and seventh steps include a twelfth step of injecting degassed ink after reducing the pressure of the ink chamber of the ink cartridge body via the ink injection needle. Can be. An ink jet recording apparatus according to an eighth aspect is characterized by mounting an ink cartridge manufactured by the manufacturing method according to the fourth to seventh aspects. In the ink cartridge, the manufacturing method thereof, and the ink jet recording apparatus according to the present invention, the ink chamber filled with the foam, the lid having the ink injection hole, the pressure reduction hole, and the air communication hole formed therein, and the air communication hole are sealed. In addition to a sealing member, an elastic body is inserted into the ink injection hole and the pressure reducing hole, and a material having no gas permeability and water vapor permeability is used for the sealing member.

[0014]

Embodiments of the present invention will be described below.

(First Embodiment) FIG. 1 is a cross-sectional view showing a first embodiment of the ink cartridge of the present invention, FIG. 2 is an exploded perspective view showing the ink cartridge of FIG. 1, and FIG. FIG. 3 is a cross-sectional view for explaining a method for manufacturing the ink cartridge of FIG.

As shown in FIGS. 1 and 2, a foam 8 made of a porous material such as a polyurethane foam is inserted into an ink chamber 2 in an ink cartridge body 1 of the ink cartridge. The ink chamber 2 is sealed by lids 12 a and 12 b having a pressure reduction hole 3, an ink injection hole 4, and an air communication hole 5.

An elastic body 6 such as butyl rubber is inserted into the ink injection hole 4 and the pressure reducing hole 3 in a compressed state. The elastic body 6 is fixed by lids 12a and 12b. The characteristics required of the elastic body 6 are ink resistance and restoring force. Needless to say, the need for ink resistance, but the need for restoring force will be described later. In addition, the decompression hole 3 can be omitted, and the manufacturing method when the omission is omitted will be described later.

The atmosphere communication hole 5 is provided with a peelable sealing member 7a.
It is sealed with. As the sealing member 7a, a material having no gas permeability and no water vapor permeability such as an aluminum sheet can be used. An ink supply unit 11 is provided on the ink cartridge body 1 on the connection side of the print head 15.
Above the ink supply unit 11, a filter 9a for filtering ink is provided.

When the ink cartridge body 1 is mounted on the print head 15, the joint 1 having the filter 9b provided on the print head case 14 is used.
3 is inserted into the ink cartridge body 1.

At this time, a packing 10 made of an elastic material such as rubber is inserted to keep the joint 13 and the ink cartridge body 1 airtight. A sealing member 7b for sealing the connection side is provided below the packing 10. Similar to the sealing member 7a, a material having neither gas permeability nor water vapor permeability can be used for the sealing member 7b.

Here, since the entire ink chamber 2 is in a decompressed state, it is necessary to open the sealing member 7a and open the atmosphere communication hole 5 to the atmosphere just before mounting the ink chamber 2 on the print head 15. . The reason will be described later.

Here, the supply of ink from the ink cartridge body 1 to the print head 15 is performed by the cap 2
0 is brought into close contact with a nozzle plate (not shown) and sucked from a pump 21 through a tube 23. When discharging the ink accumulated in the cap 20, the ink is sucked through an atmosphere release valve 22 connected to a tube 23.

After the print head 15 is filled with ink (not shown) by a suction operation, the print head 15 is filled with ink (not shown) from the relay board 16 in response to an electric signal sent through an FPC (not shown). Is applied to a plurality of ink chambers (not shown). And a nozzle (not shown) communicating with an ink chamber (not shown)
By discharging more ink (not shown), an image is formed.

Here, when the air communication hole 5 is used in an unopened state, there is no replenishment of air to the ink cartridge body 1 when the print head 15 is driven. For this reason,
When the negative pressure in the ink chamber 2 including the ink supply unit 11 increases, the meniscus formed in the nozzles (not shown) of the print head 15 is largely drawn. In this case, if the magnitude of the negative pressure exceeds the capillary force of the meniscus, the meniscus is broken, which results in poor ejection.

At the time of cartridge replacement or cleaning, the cap 20 is brought into close contact with a nozzle plate (not shown) of the print head 15, and a suction operation is performed by a pump 21 through a tube 23. However, in the unopened state of the air communication hole 5, a negative pressure remains in the ink chamber 2 after suction, so that the ink (not shown) flows backward and the ink supply to the print head 15 is incomplete.

Next, a method for manufacturing an ink cartridge having such a configuration will be described with reference to FIG.

First, the packing 10 and the filter 9a
Then, the lids 12a and 12b having the decompression hole 3 in which the elastic body 6 is inserted, the ink injection hole 4, the atmosphere communication hole 5, and the like are attached to the ink cartridge body 1 provided with the foam 8 and the like. In this state, ink is injected into the ink cartridge body 1.

At this time, the atmosphere communication hole 5 is kept sealed by the sealing member 7a. When ink is to be injected, the ink cartridge body 1 is set in the decompression chamber 30. The ink injection needle 32 is inserted into the ink injection hole 4, and the pressure reduction needle 31 is inserted into the pressure reduction hole 3 so as to pass through the elastic body 6.

Next, after the pressure in the ink chamber 2 is reduced through the pressure reducing hole 3, the undegased ink 35 in the ink tank 36 is degassed by the degassing unit 33 using a hollow fiber membrane or the like. Then, the degassed ink is supplied to the ink injection hole 4.
Inject more.

At this time, the degree of vacuum of the decompression chamber 30 is 1
60 Torr or less is desirable. After the ink injection, when the pressure reducing needle 31 and the ink injection needle 32 are retracted,
The pressure reducing hole 3 and the ink injection hole 4 are closed by the restoring force of the elastic body 6.

Therefore, even after the decompression chamber 30 is opened to the atmosphere, the decompression state of the ink chamber 2 is maintained.
As a result, since the ink degassing degree does not deteriorate, the re-degassing step becomes unnecessary. Further, in this injection method, since the ink injection needle 32 and the ink injection hole 4 are completely sealed, it is possible to prevent ink leakage at the time of ink injection and increase the amount of ink injection. It becomes possible.

Although the degree of decompression of the ink chamber 2 after the injection is in a very large state, the elastic body 6 is inserted into the ink injection hole 4 and the depressurization hole 3, and the gas permeable member is formed in the sealing member 7a. In addition, since a material having no water vapor permeability is used, ink leakage hardly occurs even with impact or temperature change.

Here, the result of measuring the degree of deaeration according to the first embodiment will be described. The degree of degassing indicates how small the amount of air contained in the ink is. Here, the measurement results of the dissolved oxygen amount (DO value) are shown in Table 1.

As a comparative example, the pressure reduction hole 3 and the ink injection hole 4
After the ink injection step, these holes are sealed at atmospheric pressure with a sealing member having gas permeability and not having water vapor permeability without inserting the elastic body 6 into the sealing member. The DO value of the noticed ink cartridge is also shown.

[0035]

[Table 1] Example: Decompression chamber vacuum degree = 160 Torr Comparative example: Decompression chamber vacuum degree = 160 Torr, decompression packaging vacuum degree = 100 Torr Time from opening to atmosphere after ink injection to decompression packaging = 5 minutes The number of measurement cartridges in both the example and the comparative example DO value measurement conditions: 25 ° C., 1 atm. For reference, the DO value of undegassed ink at 25 ° C., 1 atm is 7.5 to 8.5 mg / L.

From Table 1, it can be seen that although the degassed state of each of the examples and comparative examples has been continued for a long period of time, the initial value of the degassing degree is twice or more in the examples. This is due to the difference between whether the degassed ink comes into contact with the atmosphere or not after ink injection under reduced pressure. From the results of the comparative examples, it was confirmed that when the degassed ink was brought into contact with the atmosphere, a gas dissolved reaction occurred and the degree of degassing deteriorated.

In the comparative example, the package is packaged under reduced pressure. Although this is effective for maintaining the degree of deaeration, it is not effective for increasing the degree of deaeration. That is, it means that it is difficult to deaerate the ink only by reducing the pressure. Generally, deaeration of ink is performed by deaeration using a hollow fiber membrane, and the degree of deaeration once deteriorated cannot be increased only by reducing the pressure.

Table 2 shows the results of evaluation of the frequency of missing dots when printing was performed after performing a suction operation by exchanging cartridges by using these two ink cartridges for a print head.

[0039]

[Table 2] The number of evaluation cartridges is eight for each of the examples and comparative examples, and the above values indicate the total results.

As can be seen from Table 2, the frequency of dot omission is very low in the example, which is about 1/10 of the comparative example. this is,
The larger the degree of degassing, the easier the bubbles are to dissolve,
That is, there are few bubbles remaining in the print head. That is, the result reflects the difference in the degree of deaeration in Table 1 as it is.

As described above, in the first embodiment, the ink chamber 2 filled with the foam 8 and the lids 12a and 12b in which the ink injection hole 4, the pressure reduction hole 3, and the air communication hole 5 are formed.
And a sealing member 7 a for sealing the atmosphere communication hole 5, an elastic body 6 is inserted into the ink injection hole 4 and the pressure reducing hole 3, and a gas permeable and water vapor permeable Use of no material.

An ink injection needle 32 is inserted into the ink injection hole 4, and a pressure reduction needle 31 is inserted into the pressure reduction hole 3 so as to penetrate the elastic body 6. After that, the degassed ink was injected from the ink injection hole 4.

When the depressurizing needle 31 and the ink injecting needle 32 are retracted after the ink is injected, the depressurizing hole 3 and the ink injecting hole 4 are closed by the restoring force of the elastic body 6.

Therefore, even after the decompression chamber 30 is opened to the atmosphere, the decompression state of the ink chamber 2 is maintained.
Since the ink degassing degree does not deteriorate, it is not necessary to perform degassing again after the ink injection step, so that the decompression packaging step is not necessary, and the manufacturing process can be simplified.

In addition, since the ink injection needle 32 is completely sealed, it is possible to prevent ink leakage at the time of ink injection and to increase the amount of ink injection.

Further, the elastic member 6 is inserted into the ink injection hole 4 and the pressure reducing hole 3, and the sealing member 7a is made of a material having neither gas permeability nor water vapor permeability.
Leakage of ink can be made less likely to occur even with impact or temperature change.

Furthermore, since the ink degassed after the ink injection step does not come into contact with the atmosphere, not only the degree of degassing of the ink in the manufacturing process does not deteriorate but also the gas permeability and the water vapor permeability do not occur. Since the sealing member 7a is used, it is possible to prevent the degree of degassing of the ink from deteriorating even during long-term storage.

As described above, the print head 15
When the cartridge is mounted on the cartridge, it is possible to prevent ejection instability due to air mixing.

Further, by using the ink cartridge manufactured as described above for an ink jet recording apparatus, the ejection pressure of the print head 15 is properly maintained, and no ejection failure or dot omission occurs. In addition, not only can the reliability of the ink jet recording apparatus be improved, but also the size and cost of the ink jet recording apparatus can be reduced.

(Second Embodiment) FIG. 4 is a sectional view for explaining a method of manufacturing an ink cartridge according to a second embodiment of the present invention.

In the second embodiment, the decompression holes 3 in FIGS. 1 to 3 are omitted, and the decompression is performed through the ink injection holes 4.

That is, as shown in FIG. 4, the ink injection hole 4 in which the elastic body 6 is inserted, the air communication hole 5 and the like are provided in the ink cartridge body 1 in which the packing 10, the filter 9a, the foam 8 and the like are provided in advance. Lid 12 provided with
a, 12b are attached. In this state, ink is injected into the ink cartridge body 1.

At this time, the atmosphere communication hole 5 is kept sealed by the sealing member 7a. At the time of ink injection, the ink cartridge main body 1 is set in the decompression chamber 30. The ink injection needle 32 is inserted into the ink injection hole 4 so as to penetrate the elastic body 6.

Next, the injection valve 38 is closed and the pressure reducing valve 37 is opened, so that the pressure in the ink chamber 2 is reduced to a predetermined value. Thereafter, the pressure reducing valve 37 is closed and the injection valve 38 is opened,
The non-degassed ink 35 in the ink tank 36 is degassed by a degassing unit 33 using a hollow fiber membrane or the like, and the degassed ink is injected.

At this time, the degree of vacuum of the decompression chamber 30 is 1
60 Torr or less is desirable. When the ink injection needle 32 is retracted after the ink injection, the ink injection hole 4 is closed by the restoring force of the elastic body 6.

Therefore, even after the decompression chamber 30 is opened to the atmosphere, the decompression state of the ink chamber 2 is maintained.
The ink degassing degree does not deteriorate. This eliminates the need for a re-deaeration step. Further, in this injection method, since the ink injection needle 32 is completely sealed, it is possible to prevent ink leakage at the time of ink injection, and to increase the amount of ink injection.

Although the degree of pressure reduction of the ink chamber 2 after the injection is very large, the elastic member 6 is inserted into the ink injection hole 4 and the gas permeable and water vapor permeable The use of a non-existent material makes it difficult for ink to leak even when subjected to impact or temperature change.

As described above, in the second embodiment, the first
In addition to the effects of the first embodiment, the decompression holes 3 in FIGS. 1 to 3 are omitted, and the decompression is performed via the ink injection holes 4, so that not only the formation of the decompression holes 3 is unnecessary, but also The elastic body 6 inserted into the pressure reducing hole 3 becomes unnecessary. Further, since the decompression hole 3 is not required, the insertion of the decompression needle 31 into the decompression hole 3 shown in FIG. 3 is not required, and the manufacturing process is further simplified.

[0059]

As described above, according to the ink cartridge, the method of manufacturing the same, and the ink jet recording apparatus of the present invention, the ink chamber filled with the foam and the lid having the ink injection hole, the pressure reduction hole, and the air communication hole are formed. And a sealing member that seals the atmosphere communication hole, and an elastic body is inserted into the ink injection hole and the decompression hole, and the sealing member is made of a material without gas permeability and water vapor permeability. Therefore, the manufacturing process can be simplified and the degree of deaeration can be prevented from deteriorating.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a first embodiment of an ink cartridge according to the present invention.

FIG. 2 is an exploded perspective view showing the ink cartridge of FIG.

FIG. 3 is a cross-sectional view for explaining a method for manufacturing the ink cartridge of FIG.

FIG. 4 is a cross-sectional view for explaining a method of manufacturing an ink cartridge according to a second embodiment of the ink cartridge of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Ink cartridge main body 2 Ink chamber 3 Decompression hole 4 Ink injection hole 5 Atmospheric communication hole 6 Elastic body 7a, 7b: Sealing member (Sealable member for 7a) 8 Form 9a, 9b Filter 10 Packing 11 Ink supply Units 12a, 12b Lid 13 Joint 14 Print head case 15 Print head 16 Relay board 20 Cap 21 Pump 22 Atmospheric release valve 23 Tube 30 Decompression chamber 31 Decompression needle 32 Ink injection needle 33 Deaeration processing unit 34 Decompression pump 35 Non-degas ink 36 Ink tank 37 Pressure reducing valve 38 Injection valve

Claims (8)

[Claims] An ink chamber filled with a foam; a lid formed with an ink injection hole, a pressure reducing hole, and an air communication hole; and a sealing member for sealing the air communication hole. An ink cartridge, wherein an elastic body is inserted into the pressure reducing hole, and the sealing member is made of a material having neither gas permeability nor water vapor permeability. 2. The ink cartridge according to claim 1, wherein the pressure reducing hole is shared with the ink injection hole. 3. The ink cartridge according to claim 1, wherein the sealing member is made of a peelable material. 4. A first step of attaching a lid having an evacuation hole, an ink injection hole, and an air communication hole to the ink cartridge main body and having an elastic body inserted into the evacuation hole and the ink injection hole; A second step of inserting an ink injection needle into the injection hole so as to penetrate the elastic body; a third step of inserting a pressure reduction needle into the pressure reduction hole so as to penetrate the elastic body; A fourth step of accommodating the undegased ink in the ink tank, a fourth step of storing the ink chamber of the ink cartridge in a reduced pressure state through the pressure reducing hole through the pressure reducing needle, and A sixth step of deaeration by the deaeration section, and a seventh step of injecting the deaerated ink from the ink injection hole through the ink injection needle. And an eighth step of retracting the pressure reduction needle and the ink injection needle after the ink is injected, and closing the pressure reduction hole and the ink injection hole by a restoring force of the elastic body. A method for manufacturing an ink cartridge. 5. A ninth step in which the first and second steps include a step of sealing the atmosphere communication hole with a sealing member made of a material having neither gas permeability nor water vapor permeability. The method for manufacturing an ink cartridge according to claim 4, wherein the method is included. 6. The method according to claim 4, wherein the seventh step includes a tenth step in which the degree of vacuum in the decompression chamber is set to 160 Torr or less. 7. The second and third steps are such that the pressure reducing hole is shared with the ink injection hole, and an ink injection needle serving also as a pressure reducing needle passes through the elastic body in the ink injection hole. An eleventh step of inserting the degassed ink into the fifth and seventh steps after the ink chamber of the ink cartridge main body is depressurized through the ink injection needle. Twelfth
5. The method for manufacturing an ink cartridge according to claim 4, comprising the steps of: 8. An ink jet recording apparatus comprising an ink cartridge manufactured by the manufacturing method according to claim 4.