JP2006206190A - Liquid housing container and liquid supply apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid housing container and a liquid supply apparatus having a long life which use a gas-liquid separation membrane. <P>SOLUTION: A gas-liquid separation membrane 2 located at an air vent in a liquid housing container includes a fibril portion 2A composed of fibrous portions and an annular node portion 2B which bundles the ends of fibrous portions of the fibril portion 2A and which is closed so as to surround the fibril portion 2A. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

The present invention relates to a liquid storage container for storing a liquid such as ink, and a liquid supply apparatus.

  Conventionally, as a container for storing a liquid, a liquid storage container having a gas-liquid separation membrane that allows a gas to pass and controls the passage of the liquid is known. For example, Patent Document 1 proposes an ink jet print head having an ink tank provided with a gas-liquid separation membrane. An opening provided in a part of the ink tank is covered with a gas-liquid separation film, and the air-liquid separation film prevents air leakage while removing bubbles in the ink tank through the gas-liquid separation film. It has become.

  By installing a membrane having such a gas-liquid separation capability at the opening of the liquid storage container, the liquid can be stored without leaking, and the gas in the liquid storage container can be removed through the film. it can.

Japanese Patent Laid-Open No. 61-24458

  However, the durability of the liquid storage container using the conventional gas-liquid separation membrane is insufficient. For example, when an ink tank in which a conventional gas-liquid separation membrane is installed as in Patent Document 1 is used for a long period of time, ink (liquid) permeates into the gas-liquid separation membrane, so that the gas-liquid separation membrane The air permeability may be reduced, or the ink may not be blocked by the gas-liquid separation membrane. In such a case, the ink may leak to the outside of the ink tank, causing the recording apparatus to become contaminated or malfunction.

  Such a defect tends to be more prominent as the surface tension of the ink is smaller. However, as an ink for an ink jet recording apparatus, for example, there is an increasing demand for an ink having a low surface tension.

  Specifically, when the operation of removing the gas inside the container through the gas-liquid separation membrane is repeated by generating a pressure difference inside and outside the liquid storage container, the liquid-blocking capability of the gas-liquid separation membrane is at an early stage. In some cases, liquid leaks when the liquid penetrates into the inside. In particular, in an ink tank such as cited document 1, it is often necessary to repeat the operation of removing the internal gas through the gas-liquid separation membrane a plurality of times, and the repeated durability of the gas-liquid separation membrane is ensured. Is important.

  In addition, the gas-liquid separation membrane used in such an ink tank has as much air permeability (amount of air flow per unit area) as possible in order to reduce the pressure difference and time required to remove the gas in the ink tank. High is required. Furthermore, when a large positive pressure is temporarily generated in the ink due to expansion of the ink due to temperature change or vibration or overturning during transportation of the ink tank, there is a risk that the ink leaks outside through the gas-liquid separation membrane. In order to reduce this, a high liquid pressure resistance is required for the gas-liquid separation membrane. The liquid pressure resistance is a limit pressure required to apply pressure to a liquid such as ink that is in close contact with the gas-liquid separation membrane and allow the liquid to pass through the gas-liquid separation membrane.

  An object of the present invention is to provide a liquid storage container and a liquid supply apparatus having excellent durability using a gas-liquid separation membrane.

  The liquid storage container of the present invention is a liquid storage container having an opening in which a gas-liquid separation membrane that allows passage of gas and restricts passage of liquid can be provided, and the gas-liquid separation membrane includes a fibrous portion And an annular bundling region that is closed so as to bind the ends of the fibrous portion and surround the fibrous region.

  The liquid supply device according to the present invention is a liquid supply device having an opening in which an air / liquid separation membrane that allows passage of gas and restricts passage of liquid can be provided in an ink supply path, wherein the gas / liquid separation is performed. The membrane includes a fibrous region constituted by a fibrous portion and an annular binding region that binds an end of the fibrous portion and is closed so as to surround the fibrous region.

  The present invention is based on the viewpoints found from the results of the following experiments and their analysis and examination.

  First, a liquid storage container was prepared in which a general gas-liquid separation membrane for controlling the outflow of liquid was provided at an opening for removing gas remaining inside. When the ink as a liquid was stored in the liquid storage container and an actual use durability test was performed, ink permeation occurred in the gas-liquid separation film, and further ink leakage occurred. In particular, when a gas pressure difference is repeatedly generated between the inside and outside of the container through the gas-liquid separation membrane, and the gas in the container is repeatedly removed, the ink soaks into the gas-liquid separation membrane, In addition, leakage of liquid from the gas-liquid separation membrane occurred remarkably.

  Here, the gas-liquid separation membrane has a porous structure, a region having a very thin fibrous structure (referred to as “fibril”), and a region having a structure in which the ends of the fibrous portion are bound ( It is composed of two types (called “nodes”). Since the pore diameter of this porous structure is much larger than the size of gas molecules, the gas-liquid separation membrane has air permeability. When a liquid comes into contact with the gas-liquid separation membrane, the liquid penetrates into the pores, so that finite energy is required to pass the liquid. Therefore, when the liquid is below a predetermined limit pressure, the liquid cannot pass through the gas-liquid separation membrane.

  As a result of careful analysis and examination of the cause of the phenomenon caused by the repeated removal of the gas in the container as described above, the present inventor found that the portion of the gas-liquid separation membrane where the ink soaked or leaked occurred. I found out that the structure of the membrane was partially destroyed. Furthermore, it was found that the breakage was not at the node portion of the gas-liquid separation membrane but at the fibril portion at the fibril portion. The fiber structure of the fibril portion is largely involved in the gas-liquid separation mechanism of the gas-liquid separation membrane, and it is considered that the rupture of the fiber structure is largely related to the liquid leakage.

  The present invention has been made based on such knowledge.

  According to the present invention, the function of the opening provided with the gas-liquid separation membrane is maintained for a long period of time, and the occurrence of liquid leakage and the like is prevented, thereby improving the durability of the liquid storage container and the liquid supply device. Can be improved.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(First embodiment)
1 to 4 are views for explaining a first embodiment of the present invention. In this embodiment, the box-shaped liquid storage container 1 was created using a resin material.

  A small window as an opening was opened on the upper surface of the liquid storage container 1, and the gas-liquid separation membrane 2 was attached by thermal fusion so as to close the small window to form the vent 3. As a method of installing the gas-liquid separation membrane 2, heat fusion is suitable, but of course not limited to this. For example, mechanical fixing (caulking) or adhesion using an adhesive may be used. Further, the liquid storage container 1 is connected to a liquid supply system (not shown) so that the ink 4 as a liquid can be freely charged and discharged. The liquid supply system is for supplying ink from an ink tank to a recording head, for example. In this case, the ink tank is connected to the liquid inlet formed in the liquid storage container 1 via an opening / closing valve, and the recording head is connected to the liquid outlet opening formed in the liquid storage container 1 via the opening / closing valve. be able to.

  The gas-liquid separation membrane 2 used in this example is formed by uniaxially stretching a resin film containing polytetrafluoroethylene to form a porous structure, and then subjecting the surface to a liquid repellent treatment. For the liquid repellent treatment in this example, a method of forming a fluorine compound layer on the film surface was used. However, various generally known processing methods can be used as appropriate according to the material of the membrane and the type of liquid to be stored, and it does not have to be unnecessary.

  The surface shape of the gas-liquid separation membrane 2 is composed of a region (fibril portion) 2A having a very thin fibrous structure and a region (node portion) 2B having a structure in which ends of the fibrous portions are bound. It is made up. FIG. 2 schematically shows the surface structure of the gas-liquid separation membrane 2. 3A is a diagram in which only the fibril portion 2A is extracted from the surface structure of FIG. 2 in order to facilitate understanding of the structure of the gas-liquid separation membrane 2. FIG. Similarly, FIG. 3B is a diagram in which only the node portion 2B is extracted from the surface structure of FIG. 2 in order to facilitate understanding of the structure of the gas-liquid separation membrane 2.

  Since this gas-liquid separation membrane 2 is formed by uniaxial stretching, the fiber structure of the fibril part 2A has a structure substantially aligned in one direction, and the ends thereof are bound to form the node part 2B. Yes. Further, as a characteristic surface shape, the node portion 2B has a ring shape, and the ring structure is a continuous structure in most part. The term “annular” as used herein does not necessarily mean a circle, but includes all forms that form a “closed structure to surround” the fibril part 2A as a fibrous region. For example, the shape may be a rhombus, an oval, an ellipse, a trapezoid, or an indefinite shape as well as a circle, and includes all of the structures that are closed so as to surround the fibril part 2A as a fibrous region.

  The node portion 2B may be an annular binding region that binds the ends of the fibrous portions constituting the fibril portion 2A and is closed so as to surround the fibril portion 2A. Therefore, as apparent from FIG. 2, the size and form of the fibril part 2A surrounded by the node part 2B, the number of fibrous parts constituting the fibril part 2A, and the like are not particularly specified. Further, as is apparent from FIG. 3B, the node portion 2B is formed such that a plurality of portions surrounding different fibril portions 2A are connected.

  In such a structure, the fibrous fibril part 2A is connected to the annular node part 2B, and has a structure like a frame of a tennis racket and a gut. In such a structure, the force in the pulling direction applied to the fiber structure of the fibril part 2A is limited by the annular node part 2B, so that the fibril part 2A is less deformed and the strength against breakage is improved.

  The liquid container 1 thus prepared was filled with dye-based ink 4 (surface tension = 28 mN / m) as a liquid. And the test which repeated the operation | movement which repeatedly produces the pressure difference between the gas 5 in the container 1 and the container 1 and discharges the gas 5 in the container 1 out of the container 1 through the gas-liquid separation membrane 2 was performed. 4 (a) and 4 (b) are explanatory diagrams of the state of the test. That is, first, as shown in FIG. 4 (a), the pressure outside the container 1 is made smaller than the pressure of the gas 5 in the container 1, and the gas 5 is separated from the gas-liquid separation membrane 2 as shown in FIG. 4 (b). To discharge through. Then, after introducing the gas 5 into the container 1 as shown in FIG. 4A, it is discharged as shown in FIG. 4B. Such an operation was repeated. The gas-liquid separation membrane 2 has an air permeability of 5.7 μm / (Pa · s) in the initial state, and the pressure difference generated inside and outside the container 1 at this time is 20 kPa at the maximum, as shown in FIGS. 4 (a) and 4 (b). The number of repetitions of the gas 5 discharging operation was 10,000.

  Here, the air permeability is a value representing how much gas (air) can permeate the membrane within a unit time due to a unit pressure difference per unit area of the membrane. In particular, the definition of the air permeability defined in ISO-5636 / 5 or JIS-P8117 is generally used, and this example is also followed. The air permeability defined in this way is also called ISO air permeability.

  Then, during and after the test of the operation shown in FIGS. 4A and 4B, the state of the gas-liquid separation membrane 2 and the change in the air flow rate were observed in detail. As a result, there was no liquid permeation into the gas-liquid separation membrane or liquid leakage to the outside, which was frequently occurring in the past, and no significant decrease in the air flow rate was observed. Furthermore, as a result of careful analysis of the surface structure of the gas-liquid separation membrane 2, the membrane structure was not destroyed.

  Conventionally, it has been considered that an increase in the liquid pressure resistance of the gas-liquid separation membrane is indispensable in order to reduce liquid permeation and liquid leakage into the gas-liquid separation membrane used for such applications. In general, however, the hydraulic pressure resistance is in contradiction with the air permeability. That is, in order to improve the liquid pressure resistance, it is necessary to reduce the pore size of the gas-liquid separation membrane, and thus the air permeability must be sacrificed. However, as a result of intensive studies by the inventor, sufficient effects can be obtained by using the gas-liquid separation membrane as described above without reducing the air permeability, that is, without improving the liquid pressure resistance more than necessary. I understood that. That is, by using the gas-liquid separation membrane as described above, sufficient durability, in particular, liquid permeation and liquid leakage in the case of repeatedly removing gas can be made difficult, and repeated durability can be improved. it can.

  In this example, the liquid pressure resistance of the gas-liquid separation membrane 2 to the dye ink 4 was 60 kPa. This value is sufficiently higher than the positive pressure that can be temporarily generated inside the liquid container such as a general ink tank when the temperature changes or falls within the actual use conditions. Therefore, in an actual use state, the liquid did not leak from the liquid storage container 1 due to a temperature change or a fall.

(Second Embodiment)
In the second embodiment, the average thickness of the fibers constituting the fiber structure of the fibril part 2A is 0.2 microns. Other than that, the liquid storage container 1 which is the same as that of the first embodiment was prepared.

  The thicker the fibers forming the fiber structure of the fibril part 2A, the more rigid against stress and the more difficult it is to break. For example, assuming that the fiber has a cylindrical shape, when the thickness is doubled, the tensile rigidity is quadrupled. However, if the thickness of the fiber is made extremely thick, the pore diameter becomes small, and sufficient air permeability may not be obtained.

  Therefore, as a result of the examination, in the gas-liquid separation membrane 2 having the structure as described above, if the average thickness of the fibers constituting the fiber structure of the fibril part 2A is at least 0.1 microns or more, the present inventor It was found that sufficient strength can be obtained. The average fiber thickness here is an average value of the diameter of the thinnest part of the fiber forming the fibril part 2A, and can be measured from an electron microscope image of the gas-liquid separation membrane 2 or the like. Of course, the larger the number of samples for calculating the average value, the better. For example, if 100 or more fibers are used for the calculation, an average value with a sufficiently reliable statistical accuracy can be obtained. In the case of this example, the average thickness of the fibers in the fibril part 2A is measured from the electron microscopic image of the region of 100 μm × 100 μm by measuring the diameter of each thinnest portion of the fibers (about 300) in the region. The average value was calculated.

  Similarly to the first embodiment described above, the liquid storage container 1 of the present embodiment was filled with liquid, and the gas 5 discharging operation was repeatedly tested. The test conditions were the same as in the first embodiment. As a result, even after the repeated test, liquid permeation into the gas-liquid separation membrane 2 and liquid leakage to the outside of the gas-liquid separation membrane 2 did not occur. Furthermore, neither the air flow rate of the gas-liquid separation membrane 2 nor the membrane structure was destroyed.

(Third embodiment)
In the present embodiment, an opening 3 having a rectangular shape with a cross section of 3 mm × 7 mm in the ventilation direction is provided in the upper part of the liquid storage container 1 (see FIGS. 1A and 1B), and a gas-liquid separation membrane is disposed there to allow ventilation. The mouth was 3. At that time, the gas-liquid separation membrane was arranged so that the direction in which the fibers constituting the fibrous region were substantially aligned was parallel to the short axis (direction of length 3 mm) of the opening 3.

  As a result of the study, the present inventor has found that adopting such a configuration produces a particularly good effect for our purpose. As described above, the strength of the gas-liquid separation membrane influences the leakage of liquid due to the tearing of the fiber portion of the gas-liquid separation membrane. That is, in order to prevent tearing, it is necessary to prevent the fiber from being stretched and contracted. To that end, it is effective to suppress deformation of the entire film.

  However, for example, if the opening opened in the container is made small in order to suppress deformation of the entire membrane, there is a problem that the ventilation area is reduced and the overall air permeability is lowered.

  As a result of the study, in the gas-liquid separation membrane in which the fibers constituting the fibrous region are substantially aligned in one direction, anisotropy was observed in the membrane strength, in other words, the difficulty of deformation due to external force. That is, it was found that the gas-liquid separation membrane is soft in the direction perpendicular to the fiber orientation direction but has a very strong membrane strength in the parallel direction.

  In view of these problems, a method for suppressing liquid leakage during repeated gas removal without reducing the area has been studied, and the following configuration has been achieved. That is, the opening 3 has a cross-sectional shape (rectangular shape) having a major axis and a minor axis, and the direction in which the strength of the gas-liquid separation membrane is large, that is, the fiber orientation direction is parallel to the minor axis of the rectangular opening 3. It has been found that a liquid storage container in which the durability of the gas-liquid separation membrane is remarkably excellent can be obtained when arranged.

  Here, the opening 3 is rectangular. However, the cross section of the opening with respect to the ventilation direction has a short axis and a long axis, and the direction in which the fibers constituting the fibrous region of the gas-liquid separation membrane are substantially aligned is referred to as the short section of the opening. It goes without saying that the same effect can be obtained by arranging them so as to be parallel to the axis. The term “shape having a short axis and a long axis” as used herein refers to all figures having a short axis and a long axis that have a non-uniform distance from the center because they have no more than two line symmetry axes. Typical examples include rectangles, ellipses, ellipses, rhombuses, parallelograms, and trapezoids. It goes without saying that these corners are slightly rounded or chamfered.

  The present embodiment is particularly effective in the fourth and fifth embodiments described later.

(Fourth embodiment)
5 and 6 are diagrams for explaining the fourth embodiment of the present invention. In the case of the present embodiment, an ink ejecting apparatus that ejects ink stored in the liquid container created in the second embodiment is used as the ink container (ink tank) 1.

  The ink storage container 1 in this apparatus is configured as shown in FIGS. 5 and 6, and the gas-liquid separation film 2 is placed in the ink storage container 1 by utilizing the pressure difference between the inside and the outside of the ink storage container 1. It is provided at a position where the existing gas 5 can be discharged. That is, the ink storage container 1 in this example is provided with a vent 3 having a gas-liquid separation film 2 on its upper surface, and further provided with a cap 6 that can contact and separate from the vent 3. The cap 6 covers the vent hole 3 as shown in FIG. 6, thereby forming an airtight chamber R (see FIG. 6) capable of pressure control above the gas-liquid separation membrane 2. The cap 6 is connected to negative pressure generating means such as a negative pressure pump through an open / close valve (not shown) that can be opened and closed. Then, by introducing a negative pressure into the airtight chamber R formed as shown in FIG. 6, a pressure difference can be generated between the inside and the outside of the ink storage container 1 through the gas-liquid separation film. It is like that.

  Further, pipes 7A and 8A for constituting the ink introduction system 7 and the ink lead-out system 8 are connected to the lower part of the ink container 1. These pipes 7A and 8A are provided with valves 7B and 8B capable of controlling the flow of ink. The pipe line 7A is connected to an ink supply unit (not shown) for supplying ink into the ink storage container 1, and the pipe line 8A is an ink injection part (not shown) for jetting ink in the ink storage container 1. It is connected to the. The ink ejecting unit is, for example, an ink jet recording head. In the case of an ink jet recording head, an image can be recorded on the recording medium by ejecting ink supplied from within the ink container 1 from the nozzle onto the recording medium.

  When using such an ink storage container 1, first, ink is filled into the ink storage container 1 through the conduit 7 </ b> A of the ink introduction system 7. At that time, as shown in FIG. 5, the cap 6 is separated above the vent 3 and the valve 8B of the ink outlet system 8 is opened to prevent the pressure difference between the inside and outside of the ink container 1 to open the conduit. 8A is released.

  After the ink container 1 is filled with ink in this way, the valves 7B and 8B are closed, and the vent hole 3 is closed by the cap 6 as shown in FIG. Then, a negative pressure is introduced into the hermetic chamber R to reduce the pressure. As a result, the inside of the ink storage container 1 is depressurized through the gas-liquid separation film 2, and the gas 5 mixed and remaining in the ink container 1 passes through the gas-liquid separation film 2 to form ink from the airtight chamber R as shown in FIG. 6. It is discharged out of the storage container 1.

  Thus, after the gas 5 in the ink container 1 is discharged, the caps 6 are released as shown in FIG. Accordingly, the ink in the ink storage container 1 can be supplied to the ink ejecting section through the ink lead-out system 8 while supplying ink into the ink storage container 1 from the ink supply section through the ink introduction system 7. When the gas 5 in the ink storage container 1 is discharged through the gas-liquid separation film 2 and the gas 5 is not left in the ink storage container 1, the gas 5 is introduced into the ink ejecting portion. It can be avoided. For example, when the ink ejecting section is an ink jet recording head, if bubbles enter the inside, the energy for ejecting ink from the nozzles is absorbed by the volume change of the bubbles, or the volume of the bubbles with the temperature change Or change. In such a case, ink ejection from the nozzles may become unstable. By not allowing the gas 5 to remain in the ink storage container 1, it is possible to avoid such a problem.

  The gas 5 may enter the ink storage container 1 from the ink introduction system 7 together with the ink. For this reason, the operation of discharging the gas 5 through the gas-liquid separation membrane 2 is repeated periodically or at an appropriate timing. During the discharging operation, as described above, the valves 7B and 8B are closed, and the airtight chamber R is formed by the cap 6 as shown in FIG. 6, and then a negative pressure is introduced into the airtight chamber R. The valve 7B of the ink introduction system 7 is a normally open valve that automatically closes when the inside of the ink storage container 1 becomes a predetermined pressure or lower in order to discharge the gas 5 in the ink storage container 1. Also good. Further, as shown in FIG. 6, the sealed chamber R is always formed by the cap 6, and a negative pressure is introduced into the sealed chamber R when the gas 5 in the ink container 1 is discharged. May be released to the atmosphere.

  In the present embodiment, the discharge operation of the gas 5 is repeatedly performed in association with the ink replenishment and supply operations as described above. The pressure difference between the inside and outside of the ink container 1 during the gas 5 discharging operation was 20 kPa, and the number of repetitions of the gas 5 discharging operation was 10,000. As a result, ink permeation into the gas-liquid separation membrane 2 and ink leakage did not occur, and the durability could be improved repeatedly.

(Fifth embodiment)
FIG. 7 is a diagram for explaining a fifth embodiment of the present invention. In the ink storage container 1 of the present embodiment, a gas-liquid separation membrane 2 is used to replenish the ink 4 therein.

  The ink container 1 is provided with an ink supply port 1A, an ink supply port 1B, and a suction port 1C. The ink supply port 1A is connected to the supply path 11 of the ink 4, the ink supply port 1B is connected to an ink supply path (not shown) for supplying the ink 4 to the ink jet recording head, and the suction port 1C is a negative pressure pump. Or the like to the negative pressure supply path 12. The suction port 1 </ b> C is provided with a gas-liquid separation film 2, and a negative pressure is introduced into the ink storage container 1 through the gas-liquid separation film 2.

  When the liquid level L of the ink 4 in the ink storage container 1 is lowered as indicated by the solid line in FIG. 7 and the ink 4 needs to be replenished into the ink storage container 1, it is first connected to the ink supply port 1B. Close the ink supply path. Then, a negative pressure is introduced into the ink container 1 from the suction port 1 </ b> C through the gas-liquid separation membrane 2. Due to the negative pressure, ink is sucked into the ink storage container 1 from the ink supply path 11 through the ink supply port 1A. With such ink suction and replenishment, the liquid level L gradually rises, and the liquid level L rises to the position of the two-dot chain line in FIG. When this is done, the suction replenishment of the ink 4 automatically stops. That is, since the gas-liquid separation film 2 allows the gas 5 in the ink storage container 1 to pass and prevents the ink 4 from passing, the ink level is reached when the liquid level L reaches the position of the gas-liquid separation film 2. The suction supply will automatically stop.

  Thus, the gas-liquid separation membrane 2 can also be used for supplying a predetermined amount of ink 4 into the ink storage container 1.

  In the present embodiment, a configuration is shown in which ink is filled while pressure is reduced from the outside of the ink storage container to generate a differential pressure inside and outside the ink storage container and gas is excluded. However, it is also possible to employ a configuration in which the inside of the ink storage container is pressurized to create a differential pressure inside and outside the ink storage container, and the ink is filled while excluding gas.

(Other embodiments)
The liquid storage container of the present invention can be widely applied not only as ink but also as a container for storing various liquids.

  Further, in the present invention, a gas is discharged from the inside of the liquid storage container to the outside through the gas-liquid separation membrane by generating a differential pressure (a low internal pressure and a high external pressure difference) inside and outside the liquid storage container. Can be achieved. In the first to fourth embodiments described above, the opening of the liquid storage container in which the gas-liquid separation membrane can be arranged has a vent hole that can discharge the gas in the liquid storage container to the outside through the gas-liquid separation film. did. In the fifth embodiment described above, the opening of the liquid storage container in which the gas-liquid separation membrane can be arranged is a suction port into which a negative pressure for sucking liquid through the gas-liquid separation membrane can be introduced. However, the opening part of the liquid storage container in which the gas-liquid separation membrane can be arranged may be an opening part for applying atmospheric pressure to the liquid storage container through the gas-liquid separation film.

  The present invention is also applicable to a liquid supply apparatus having the same components as the above-described liquid storage container in the liquid supply path, or a liquid supply apparatus having the above-described opening in the liquid supply path. Can do. The liquid supply path is a path for supplying the liquid from the liquid replenishment section to the liquid use section such as a liquid storage container or an ink jet recording head. In addition, when such an opening as described above is provided in the liquid supply path, as described above, a pressure difference is positively generated between the inside and outside of the gas-liquid separation membrane disposed in the opening. The structure for making it can be provided.

(A) is a schematic perspective view of the liquid storage container in the 1st Embodiment of this invention, (b) is a schematic sectional drawing of the liquid storage container. It is a schematic diagram of the surface structure of the gas-liquid separation membrane in FIG. (A) is the schematic diagram which extracted only the fibril part from FIG. 2, (b) is the figure which extracted only the node part from FIG. (A), (b) is a schematic sectional drawing for demonstrating the repetition test of the discharge | emission operation | movement of the gas with respect to the liquid storage container of FIG. It is a schematic sectional drawing of the liquid storage container in the 4th Embodiment of this invention. It is a schematic sectional drawing at the time of the gas discharge operation | movement of the liquid storage container of FIG. It is a schematic block diagram of the liquid storage container in the 5th Embodiment of this invention.

Explanation of symbols

1 Liquid container (ink container)
2 Gas-liquid separation membrane 2A Fibril part 2B Node part 3 Vent (opening)
4 Liquid (ink)
5 Gas 6 Cap 7 Ink introduction system 8 Ink delivery system R Airtight chamber

Claims (8)

A liquid storage container having an opening in which a gas-liquid separation membrane that allows passage of gas and restricts passage of liquid can be provided,
The gas-liquid separation membrane includes a fibrous region constituted by a fibrous portion, and an annular binding region that binds an end portion of the fibrous portion and is closed so as to surround the fibrous region. Characteristic liquid storage container.   The liquid container according to claim 1, wherein an average thickness of the fibrous portion is 0.1 microns or more.   The liquid container according to claim 1 or 2, wherein the fibrous portions are arranged substantially in one direction.   The liquid container according to any one of claims 1 to 3, wherein a material of the gas-liquid separation membrane includes polytetrafluoroethylene.   A differential pressure of an external pressure is lower than an internal pressure of the liquid storage container, and the gas existing in the liquid storage container is discharged to the outside through the gas-liquid separation membrane. The liquid storage container according to claim 1.   The cross-section has an opening made up of a short axis and a long axis, and the fiber arrangement direction of the gas-liquid separation membrane disposed in the opening is substantially parallel to the short axis direction of the opening. The liquid container according to claim 3.   The liquid storage container according to claim 1, wherein the liquid storage container constitutes an ink tank that stores liquid ink. A liquid supply apparatus having an opening in which a gas-liquid separation membrane that allows passage of gas and restricts passage of liquid in a liquid supply path can be provided,
The gas-liquid separation membrane includes a fibrous region constituted by a fibrous portion, and an annular binding region that binds an end portion of the fibrous portion and is closed so as to surround the fibrous region. A liquid supply device.

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