JP3498524B2 - ink cartridge - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink cartridge used in an inkjet printer or the like.

[0002]

2. Description of the Related Art Conventionally, an ink cartridge used in an ink jet printer has a porous material such as ink.
That is, it is known that a foam material is impregnated and placed in a cartridge case. In this way, the ink is carried in the foam material only when the ink is filled in the cartridge case, the ink is excessively supplied to the recording head due to its weight, vibration during printing or during transportation. The vibration of the ink causes the liquid surface of the ink to sway, and it is easy for air to be drawn into the ink. If the drawn air is sucked into the supply holes of the ejection nozzle, the ink may remain sufficiently in the cartridge. This is because, regardless of this, the ejection of ink may be interrupted and the print quality may be degraded.

When the ink is present in the foam material, an appropriate amount of the ink is supplied to the recording head by the capillary force of the foam material, and even if there is vibration, the liquid surface of the ink does not shake and air is entrained in the ink. Therefore, the ink ejection can be performed without interruption, and the printing quality can be maintained high.

[0004]

However, the following problems may occur due to the presence of the foam material.
In order to arrange the foam material and ink in the cartridge case, first, after inserting the compressed foam material into the cartridge case through the opening, the lid is attached to the opening by heat welding or the like. After that, the ink is injected from the ink supply hole or the air opening hole and penetrates into the foam material. Finally, the atmosphere communication hole and the ink supply hole are sealed with a sealing material, packed in a bag, and shipped.

However, even when the compressed foam material is inserted into the cartridge case, the inner surface of the cartridge case and the outer surface of the foam material may not be in complete contact with each other. For example, as shown in FIG. 6, foam material 55
At the time of insertion of the foam material 55, a part of the foam material 55, in particular, a corner 55a is caught on the inner wall surface 51 of the cartridge case 50, and the foam material 55 is distorted. In some cases, a relatively large gap portion 60 was formed between the two.

The injected ink collects in such a gap 60, but the ink accumulated in such a relatively large gap 60 is more resistant to flow than the ink carried in the foam material 55. There is little and it is easy to flow. Therefore, although the ink is still sufficiently remaining in the foam material 55, the ink existing in the gap portion 60 is consumed first, and the ink is discharged from the atmosphere communication hole through the gap portion 60. Air reaches the ink supply holes. When the air reaches the ink supply hole from the atmosphere communication hole in this way, the flow resistance of the air is smaller than that of the ink existing in the foam material 55, and thus the air is preferentially supplied to the ink supply hole. .

Therefore, although the ink is sufficiently left in the foam material 55, the ink is not supplied,
There is a problem that printing quality is deteriorated because printing by the printer becomes impossible or printing is cut out. It is an object of the present invention to prevent the above-mentioned problems by reducing or eliminating the gap portion generated between the porous body such as the foam material and the cartridge case to the extent that the above-mentioned problem does not occur. To do.

[0008]

Means for Solving the Problems and Effects of the Invention The ink cartridge of the present invention comprises a cartridge case having an ink supply hole and an atmosphere communicating hole, a porous body disposed in the cartridge case, and a porous body. An ink cartridge having the ink absorbed and supported by the above, wherein the porous body is swollen by being heat-treated while at least the porous body and the ink are accommodated in the cartridge case. It is characterized by.

When this heat treatment is performed, the porous body swells more rapidly than at room temperature, and the volume of the entire porous body tends to increase, so that when a gap exists in the cartridge case. The porous body almost fills the gap. This swelling is performed by the material forming the porous body absorbing the ink component, that is, since the porous body swells by the amount of the ink present in the gap, the porous body and the ink are separated from each other. The total volume remains the same and does not destroy the cartridge case. Even at room temperature, the porous material has the property of swelling little by little due to the ink components, but at room temperature, it does not swell to the extent that the gap disappears from normal manufacturing to shipping and use by consumers.

In the ink cartridge of the present invention, the gap has already been reduced or disappeared to the extent that the above-mentioned problems do not occur due to the heat treatment during manufacturing. Therefore, the ink is sufficiently contained in the porous body. It is possible to prevent the printing from being disabled by the printer or the like because the ink is not supplied although the ink remains.

Further, as described above, since the porous body swells as much as the ink existing in the gap is taken in and the total volume of the porous body and the ink does not change, at least the inside of the cartridge case is Even after the porous body and the ink are stored, the cartridge case is not destroyed due to the internal expansion even if the heat treatment is performed with the ink supply hole and the air communication hole sealed. Further, it may be packaged and then heat-treated.

The porous body is usually a foam made of a resin material. Examples of such a resin material include urethane foam resin and foam melamine resin. As the heat treatment, for example, at about 60 ° C. or higher,
In addition, it is preferable to perform the heating within a range of the lowest temperature among the heat resistant temperatures of the cartridge case, the porous body and the ink.

The heat treatment time is preferably about 1 hour or more. In particular, it is more preferable to perform the treatment for about 2 hours or more in order to realize sufficient swelling. The ink cartridge manufactured in this way is
For example, it is used in an inkjet printer.

[0014]

DETAILED DESCRIPTION OF THE INVENTION

[First Embodiment] FIG. 1 is a schematic vertical sectional view of an ink cartridge 2 to which the above-described invention is applied.

The ink cartridge 2 is used in an ink jet printer for ejecting ink onto a recording medium for printing, and has a rectangular parallelepiped cartridge case 4 whose upper surface is opened through an opening 4a. The opening 4a is closed by the lid 6.

As shown in a partially enlarged view of FIG. 2, ink is supplied to one side of the cartridge case 4 to supply ink to the ink supply manifold 5a of the ink jet recording head 5 when set and used in the ink jet printer. A supply hole 4b is formed, and an atmosphere communication hole 4c is formed on the other side of the cartridge case 4. Further, inside the position where the atmosphere communication hole 4c is formed,
An air buffer 4d is formed to prevent ink from evaporating through the atmosphere communication hole 4c.

Inside the cartridge case 4, an ink chamber 4e is provided on the ink supply hole 4b side, and a porous body 4f capable of storing ink (here, urethane foam resin is used) on the atmosphere communication hole 4c side. ) Is filled with the foam chamber 4g, and the two chambers 4e and 4g are communicated with each other at the lower part via the communication portion 4h.

A mesh filter member 8 for removing dust and the like contained in the ink supplied to the ink jet recording head 5 on the ink jet printer side, and an adapter 10 for connecting to the ink jet recording head 5 are provided in the ink supply holes 4b. Is provided.

The ink cartridge 2 is manufactured as follows. That is, as shown in FIGS. 3A and 3B, first, the inside of the foam chamber 4g of the cartridge case 4 is filled with the porous body 4f compressed from the opening 4a provided on one surface (upper surface). To be done. After that, the lid 6 is heat-welded, and then the degassed ink is filled through the ink supply hole 4b by the ink injection means (not shown). Note that FIG. 3A is a vertical cross-sectional view as viewed from the left side when vertically cut in a direction perpendicular to FIG. 3B.

This ink injection process is performed as follows. That is, an ink injection means (not shown) is connected to the ink supply hole 4b. Then, when the ink is injected, first, the negative pressure means is applied to the atmosphere communication hole 4c prior to the ink injection to bring the inside of the ink cartridge 2 into the negative pressure state.

Then, the inside of the ink cartridge 2 is in a predetermined negative pressure state (for example, 1 atm is 0 mmHg, -71
In the state of about 0 mmHg), the ink injection by the ink injection means is started. The injected ink is easily sucked into the ink cartridge 2 because the inside of the ink cartridge 2 is in a negative pressure state. At this time, the ink collides with the partition wall 4i that separates the foam chamber 4g and the ink chamber 4e and separates into upper and lower parts. First, the ink mainly flows toward the ink chamber 4e having a small flow resistance to fill the ink chamber 4e. Then, it flows into the foam chamber 4g through the communication portion 4h at the bottom. This makes the foam room 4g
Ink permeates into the porous body 4f inside the porous body 4f.
satisfy f.

Finally, one long sealing material 12 is heat-welded to the ink supply hole 4b, the atmosphere communication hole 4c, the cartridge case 4 and the lid 6 to completely seal the ink supply hole 4b and the atmosphere communication hole 4c. Stop. The ink supply hole 4b
The end 12a of the side sealing material 12 is the cartridge case 4
Is heat-welded to the bottom portion of the above, but the end portion 12b on the atmosphere communication hole 4c side is not heat-welded. This is for the user to peel off the sealing material 12 from the end 12b on the side of the atmosphere communication hole 4c.

Next, the ink cartridge 2 is placed at 60.degree.
The porous body 4f in the ink cartridge 2 is swollen with the ink by being left in the atmosphere for 2 hours or more for heat treatment. As a result, when the porous body 4f is filled in the foam chamber 4g, as shown in FIG.
Even if 0 is formed, the porous body 4 associated with this heat treatment
Due to the swelling of f, as shown in the partially enlarged sectional view of FIG.
The gap 20 almost disappears, and there is practically no problem.

That is, in the ink cartridge 2 after the heat treatment as described above, the ink in the gap 20 is supplied to the ink jet recording head side from the ink supply hole 4b prior to the ink in the porous body 4f. There is no. Alternatively, at least the air does not enter the gap 20. Therefore, even though the ink is sufficiently left in the porous body 4f, air is not supplied to the inkjet recording head 5 side to make printing impossible or to deteriorate the print quality. Therefore, the ink inside the porous body 4f is effectively used.

FIG. 5 shows the relationship between the heat treatment conditions obtained by the experiment and the ink use efficiency. FIG. 5A shows 60
The relationship between the heat treatment time t at ° C and the use efficiency M (%) of the ink filled in the ink cartridge 2 is shown.
Here, the ink use efficiency is a value represented by the following equation.

[0026]

[Equation 1]

Here, S: inkjet recording head 5
Is the total amount of ink ejected from P, and P is the amount filled in the ink cartridge 2. From the data in FIG. 5A, it can be seen that the longer the heat treatment time t, that is, the more sufficient the swelling of the porous body 4f is, the higher the use efficiency M is. The usage efficiency M, which was 75% without heating,
It can be seen that the usage efficiency M has risen to 81% just by heating for 1 hour. In particular, for 2 hours or more, the usage efficiency M =
At 83%, almost equilibrium is reached. Therefore, it can be seen that heat treatment for 1 hour or more, preferably 2 hours or more is sufficient.

Further, FIG. 5B shows the relationship between the heating temperature T and the use efficiency M (%) of the ink filled in the ink cartridge 2 when the heating process is performed for 2 hours by changing the heating temperature variously. Shows. From the data in FIG. 5B, it can be seen that the higher the heating temperature T, that is, the higher the temperature of the porous body 4f, the higher the use efficiency M. 40 ° C
However, it can be seen that the usage efficiency M has risen to 80%.
Particularly, at 60 ° C. or higher, the use efficiency M = 83%, and almost equilibrium is reached. Therefore, 40 ° C or higher, preferably 6
It can be seen that heat treatment at 0 ° C. or higher is sufficient. However, it doesn't matter how high the temperature is.
The heat treatment is performed within the minimum temperature range of the heat resistant temperatures of the cartridge case 4, the porous body 4f, and the ink.

[Others] Although the ink cartridge 2 is actually packed in a bag and shipped, the heat treatment for swelling the porous body 4f may be performed after the packing. In this case, the heat treatment is carried out within the minimum temperature range of the heat resistant temperatures of the bag body, the cartridge case 4, the porous body 4f and the ink.

[Brief description of drawings]

FIG. 1 is a schematic vertical cross-sectional view of an ink cartridge according to an embodiment.

FIG. 2 is a partially enlarged view of the ink cartridge when in use.

FIG. 3 is a diagram illustrating a part of a manufacturing process of the ink cartridge.

FIG. 4 is a partially enlarged sectional view of the ink cartridge.

FIG. 5 is a graph showing the relationship between heat treatment conditions and ink use efficiency M in the ink cartridge.

FIG. 6 is a partially enlarged sectional view of a conventional ink cartridge.

[Explanation of symbols]

2 ... Ink cartridge 4 ... Cartridge case 4a ... Opening 4b ... Ink supply hole 4c ... Atmosphere communicating hole 4d ... Air buffer 4e ... Ink chamber 4f ...
Porous body 4g ... Foam chamber 4h ... Communication part 4i ... Partition wall 5 ... Ink jet recording head 5a ... Ink supply manifold 6 ... Lid body 8 ... Mesh filter member 10 ... Adapter 12 ... Sealing material 12a ... Sealing material end 12b ...
Seal material end 20 ... Gap

Claims (7)

(57) [Claims] 1. An ink cartridge comprising: a cartridge case having an ink supply hole and an atmosphere communication hole; a porous body arranged in the cartridge case; and ink absorbed and carried by the porous body. The ink cartridge is characterized in that the porous body is swollen by being heat-treated while at least the porous body and the ink are accommodated in the cartridge case. 2. The cartridge case is stored with at least a porous material and ink, and is then heat-treated in a state where the ink supply hole and the atmosphere communication hole are sealed. Ink cartridge. 3. The ink cartridge according to claim 1, wherein the porous body is a foam made of a resin material. 4. The heat treatment is performed at about 60 ° C. or higher, and
The ink cartridge according to any one of claims 1 to 3, wherein the temperature is lower than or equal to the lowest temperature among the heat resistant temperatures of the cartridge case, the porous body and the ink. 5. The ink cartridge according to claim 4, wherein the heat treatment time is about 1 hour or more. 6. The ink cartridge according to claim 4, wherein the heat treatment time is about 2 hours or more. 7. The ink cartridge according to claim 1, which is used in an ink jet printer.