JP2004175055A - Liquid storage container and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid storage container which can make an interface between a content liquid and a follower fluid into a flat and stable shape and minimizes such problems that the follower fluid does not follow the consumption of the content liquid and the content liquid leaks beyond a layer wall of the follower fluid. <P>SOLUTION: The liquid storage container has the follower fluid layer provided on an ink interface. The follower fluid is temporarily held by a lid and rotated to apply a centrifugal force, so that the interface of the content liquid and the follower fluid are brought into contact, whereby a gas interposed between the content liquid and the follower fluid is discharged to a vent hole side of the follower fluid. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention is a writing implement or applicator, which can contain a liquid content to be discharged through a discharge port of a pen tip, a coating destination, a printer head or the like in a so-called free state in which a liquid occluding substance such as a fiber convergence body is not absorbed. The present invention relates to a container for storing a discharged liquid such as a cosmetic container or an ink tank cartridge of an ink jet printer.
[0002]
[Prior art]
In ink tanks, such as writing instruments, applicators, and ink jet printer ink tanks, ink can be stored directly and freely in a free state, and if it is possible to secure an abundant amount of ink, follower fluids are arranged in layers at the ink interface. Then, a negative pressure means for holding the ink in the ink tank and a device which prevents the ink from directly contacting the atmosphere and prevent the air from being dissolved in the ink are known. For example, an ink jet printer ink tank (see Patent Document 1) and a writing instrument (see Patent Document 2) connected to an ink jet printer.
[0003]
[Patent Document 1]
JP 2001-301191 A (page 2, right column, line 35 to page 3, right column, line 36, FIGS. 1 to 3)
[Patent Document 2]
Japanese Utility Model Registration No. 2590375 (page 2, right column, fourth line to page 3, left column, third line, FIGS. 1 to 3)
[0004]
[Problems to be solved by the invention]
However, containers such as ink tanks for ink jet printers and writing implements disclosed in the above-mentioned prior art publications have difficulty in arranging follower fluid in a layer on the interface of ink, especially when the inside diameter is large. Was. In other words, the viscosity and surface tension of the ink contained in the container cannot be said to be too high, and the ink is easily deformed by an external force. In some cases, the pressure and the weight of the follower fluid were applied, and the interface of the ink was deformed, making it difficult for the ink to become flat. In particular, usually, the outer diameter of the discharge port of the filling nozzle is smaller than the area of the container at the interface of the ink, and the interface of the ink communicates with the atmosphere. Therefore, the interface of the ink is freely deformed by the pressure when the follower fluid is filled on the interface of the ink and the weight of the follower fluid, and this phenomenon appears remarkably. If the interface between the ink and the follower fluid is not flat, the follower fluid will not follow the interface of the ink that moves as the ink is consumed, or if the impact is applied or the ambient temperature rises, the follower fluid layer It was feared that the ink would leak out beyond the wall.
[0005]
[Means for Solving the Problems]
That is, the present invention comprises a container body having a discharge port and a lid having a ventilation hole, and accommodates, in a free state, a content liquid to be discharged from the discharge port to the outside in the container, and an interface of the content liquid. Liquid that is substantially incompatible with the content liquid and has a specific gravity equal to or less than the value of the content liquid, and is arranged in a layered manner so as to move following an interface movement accompanying a decrease in volume due to discharge of the content liquid. In the storage container, the lid may be a liquid storage container having a temporary follower fluid storage chamber having a volume equal to or larger than the volume in which the follower fluid is stored and arranged, and the follower may be inserted into the temporary follower fluid storage chamber of the lid. After filling the fluid, it is installed in the container body filled with the content liquid, and is rotated with the vent hole of the lid positioned inside to apply a centrifugal force to bring the interface of the content liquid into contact with the follower fluid. ,this And gist a method for manufacturing a liquid container for discharging gas interposed vent side of the follower fluid between the volumes liquid and follower fluid.
[0006]
[Action]
In filling the inner solution and the follower fluid into the container, the interface of the content liquid is not directly filled with the follower fluid. That is, the lid part filled with the follower fluid in the temporary follower fluid storage chamber is attached to the liquid storage part storing the content liquid, and the interface of the content liquid is brought into contact with the follower fluid by centrifugation. The centrifugal force is a force that strongly exerts the separability due to the difference in specific gravity between the two, and since the force is more uniformly applied overall, it is presumed that a flat interface can be formed. .
[0007]
【Example】
Hereinafter, an example will be described with reference to the drawings.
The one shown in FIG. 1 assumes an ink cartridge that is replaceably attached to a printer body (not shown). This ink cartridge basically includes a tank body 2 having a discharge port 2a for ink 1 and a lid 3 having a vent 3a. Each of them is an injection molded product of a polypropylene resin having a low gas permeability and a high light permeability, and a joint portion between the protrusions is a crossover fitting of protrusions for securing circumferential contact. Other examples include fusion by ultrasonic waves and bonding by an adhesive or the like. Inside,
About 25 cc of ink 1 (specific gravity: about 1.07) and 2.6 cc of high-viscosity gel-like fluid 4 (specific gravity: about 0.88) as a follower fluid of ink 1 by contact with the interface of the ink. I have.
[0008]
A filter 5 and a valve body 6 are arranged in the ink discharge port 2a in order from the inside, and coarse particles such as aggregates and reactants of pigments and other compounds which may be present in the ink 1 and a high-viscosity gel-like fluid are provided. 4. Also, it is possible to prevent air bubbles and the like remaining in the ink 1 from entering the printer head and the communication path to the printer head.
The valve body 6 is an elastic valve made of an elastic material such as silicone rubber, butyl rubber, ethylene propylene rubber, etc., and is deformed in response to a demand such as a suction force from a printer head to open the ink passage 6a having a one-character slit shape. Can be. The filter 5 is a twilled weave, 0.06 mm thick, 3000 MESH stainless steel wire mesh. The wire mesh may be plain woven, twilled weave, warp stranded plain weave, co-twisted woven, plain weave, twill weave, cedar twill weave, and the like. The thickness is 0.06 mm to 2.00 mm, and the mesh is 1200 MESH. ~ 3500 MESH is preferred. Although not shown, the functions of the filter 5 and the valve body 6 may be provided by a plate member made of communicating porous polyurethane or polyethylene resin which is thermally compressed so that the skeleton portions thereof come into contact with each other. .
[0009]
The ink 1 housed inside is assumed to be a water-based dye ink using water as a main medium using a dye as a coloring agent, but it is also possible to use a pigment ink or an oil-based ink using an organic solvent as a main medium. it can. The high-viscosity gel-like fluid 4 needs to be substantially incompatible with the ink 1. When an oil-based ink is used, an aqueous high-viscosity gel-like fluid 4 using water as a medium can be used. However, since the aqueous high-viscosity gel-like fluid has high gas permeability or is easy to dry, a layer of an oil-based backflow / permeation / drying inhibitor composition using an organic solvent as a medium is further provided thereon. May be formed.
[0010]
The inner wall surface of the tank body 2 which is an injection-molded product of a polypropylene resin is made of polybutene having an average molecular weight of 630, and is gelled with fine particle silica and dextrin fatty acid ester to impart viscoelasticity and have a high viscosity gel-like fluid having transparency. 4, the contact angle with the high-viscosity gel-like fluid 4 is set at 58 ° (25 ° C.), and when the layer of the high-viscosity gel-like fluid 4 moves, it adheres to the inner wall surface of each ink chamber and remains. High-viscosity gel-like fluids that can be minimized. The viscosity of the high-viscosity gel-like fluid 4 is set to 1960000 mPa · s (25 ° C.) so that the movement of the high-viscosity gel-like fluid 4 is smooth, however, a layer is formed between the inside wall of each ink chamber. Are formed so that no cuts are formed. Further, when the environmental temperature rises with the ink discharge port 2a facing upward or sideways, the high-viscosity gel-like fluid 4 does not flow out of the vent 3a, and the shape of the high-viscosity gel-like fluid 4 can be maintained. I have.
In particular, the contact angle between the high-viscosity gel-like fluid 4 and the inner wall surface of each ink chamber is preferably 30 ° or more and 90 ° or less. When the angle is less than 30 °, the high-viscosity gel fluid 4 is extremely strongly adhered to the inner wall surface of each ink chamber, and the movement of the layer of the high-viscosity gel fluid 4 may be hindered. In addition, the amount of the high-viscosity gel-like fluid 4 that adheres to and remains on the inner wall surface of each ink chamber even when moved is increased. A large amount of high-viscosity gel-like fluid 4 must be disposed in order to obtain a backflow-preventing effect and its sustainability in the high-viscosity gel-like fluid 4, which is uneconomical in terms of volume and cost. On the other hand, when the angle exceeds 90 °, the inner wall surface of each ink chamber becomes extremely hard to get wet, and the backflow prevention function may not be effectively exhibited. Further, there is a concern that the ejection resistance of the ink 1 is too low and the ink 1 adheres to the printer head. In a state where the ink 1 adheres to the printer head, there is a concern that unnecessary uncontrolled ink 1 is used at the time of next printing, which may affect print quality.
The contact angle and the viscosity can be adjusted by the composition of the high-viscosity gel fluid 4, the material of the tank body 1, the surface condition of the wall surface, and the like. In addition to this example, low molecular weight polybutene or α-olefin having an average molecular weight of 300 to 3700 can be suitably used as the substrate.
[0011]
A method for manufacturing the ink tank of this embodiment will be described with reference to FIGS.
First, as shown in FIG. 2, the lid 3 is placed with the vent hole 3a facing downward, and the required amount of the high-viscosity gel fluid 4 is filled into the lid 3 in this state while moving the filling nozzle 7. After filling the high-viscosity gel fluid 4, the lid 3 is fitted over the tank body 2 filled with the ink 1, and the container is closed (FIG. 3). Thereafter, centrifugal treatment is performed with the discharge port 2a on the outside and the ventilation hole 3a on the inside. Since the specific gravity of the high-viscosity gel fluid 4 is higher than that of the air interposed between the ink 1 and the high-viscosity gel fluid 4, the high-viscosity gel fluid 4 exchanges its position with the air and moves in the interface direction of the ink 1. By moving, the state of FIG. 1 can be obtained.
[0012]
In addition, the shape of the nozzle for filling the high-viscosity gel-like fluid 4 is not limited to the one shown in the figure, and a filling nozzle having a plurality of relatively small-diameter discharge ports may be used to transfer the high-viscosity gel-like fluid 4 at a time to the tank lid 3. May be filled. However, in any case, if air is entrapped at the time of filling, the amount of the high-viscosity gel-like fluid 4 that can be filled in the lid 3 is reduced. Therefore, care should be taken to minimize the entrapped air. .
[0013]
FIG. 4 shows another example of the lid 3.
This lid 3 does not need to change the direction of the lid 3 when filling the high-viscosity gel-like fluid 4. The vent 3a is arranged inside the tank, and the high-viscosity gel-like fluid 4 can be filled into the tank from the vent 3a by centrifugation. Thereby, the outflow due to the contact angle and the viscosity of the high-viscosity gel-like fluid 4 until the lid 3 is covered with the tank body 2 is minimized. Therefore, the range of the contact angle and the viscosity of the high-viscosity gel-like fluid 4 can be set only by the discharge function of the ink 1 after the production, which is preferable.
[0014]
FIG. 5 shows another example.
FIG. 5 shows an example in which one ink cartridge is filled with four colors of ink. The ink chamber is partitioned into four ink chambers by a wall 2b formed integrally with the tank body 2. Approximately 10 cc of each ink 1 of black, cyan, magenta, and yellow (specific gravity: about 1.06) is placed in each ink chamber. Specific gravity: about 0.89) is accommodated in 2.0 cc.
[0015]
The inner wall surface of each ink chamber, which is an injection-molded article of the polypropylene resin of this example, is based on an α-olefin having an average molecular weight of 420, is gelled by fine particle silica and dextrin fatty acid ester, imparts viscoelasticity, and has high transparency. The contact angle with the high viscosity gel fluid 4 is set to 69 ° (25 ° C.) by the viscosity gel fluid 4. When the layer of the high-viscosity gel-like fluid 4 moves, the amount of the high-viscosity gel-like fluid 4 that adheres to and remains on the inner wall surface of each ink chamber is reduced as much as possible. Further, the viscosity of the high-viscosity gel-like fluid 4 is set to 1240000 mPa · s (25 ° C.) so that the movement of the high-viscosity gel-like fluid 4 is smooth, however, a layer is provided between the inner wall surface of each ink chamber. Are formed so that no cuts are formed.
[0016]
As shown in FIG. 6 which is a cross-sectional view taken along the line II ′, an inner wall of the lid 3 is provided with a vent wall 3b and a partition wall 3b, which communicate with each other. It is as if a small space is formed. Even when the vent hole 3a of the tank lid 3 is in the upward state, the capillary force of the small space formed by the partition wall 3b, the contact angle of the high-viscosity gel-like fluid 4 with the inner wall surface of the tank lid 3, and the high viscosity Due to the viscosity of the gel fluid 4, the high viscosity gel fluid 4 is held by the tank lid 3. Thereby, even if the direction of the lid 3 is changed in manufacturing, the outflow of the high-viscosity gel-like fluid 4 from the lid 3 before the lid 3 is covered with the tank body 2 is minimized. is there.
[0017]
FIG. 7 shows another example.
FIG. 7 shows an example of a so-called raw ink type writing instrument in which ink 1 in a free state which is not held by an ink occluding body such as a fiber convergence body is stored. A metal ball-point pen tip 9 is press-fitted and fixed to the opening at the tip of the ink cylinder 8 as a liquid container. Further, the ink cylinder 8 has a substantially cylindrical shape with an inner diameter of about 8 mm in a portion for accommodating the ink 1 and is an injection molded article of polypropylene, which is a synthetic resin having excellent gas impermeability and having transparency, The remaining amount of ink is visible.
Inside the ink cylinder 8, a dye is used as a colorant in a free state, and 2 cc of an aqueous dye ink 1 (specific gravity: 1.10) using water as a main medium is brought into contact with the interface of the ink 3 to have a high viscosity. 0.2 cc of gel-like fluid 4 (specific gravity: 0.90) is stored.
[0018]
A cup-shaped floating body 10 is disposed so as to be partially immersed in the high-viscosity gel-like fluid 4. The floating body 10 has a cross section along the inner wall cross section of the ink cylinder 8 (that is, if the cross section of the ink cylinder 8 is circular, it is circular, and if it is square, it is quadrilateral). The gap with the inner wall is filled with the high-viscosity gel fluid 4. This floating body 10 makes it easy to keep the shape of the layer of the high-viscosity gel-like fluid 4 stable during use, and the ink easily leaks because the interface between the ink 1 and the high-viscosity gel-like fluid 4 is inclined. It has a role to control the situation. Further, since the floating body 10 is of a cup type, the amount of the resin material used can be reduced, which is advantageous in terms of cost. (A phenomenon in which dents are formed on the outer surface due to partial differences in shrinkage speed and non-uniformity). However, it may be a solid mass.
[0019]
At the rear opening of the ink cylinder 8, a tail plug 11 of an injection molded product of polypropylene, which is a synthetic resin colored or dyed in an ink color as a color display, is press-fitted and fixed. The tail plug 11 is formed with a vent hole 11 a as an air flow passage, and allows the outside air to communicate with the rear part of the high-viscosity gel-like fluid 4. Further, a guide portion 11b is arranged to extend to the ventilation hole 11a of the tail plug 11.
[0020]
The inner wall surface of the ink cylinder 8 has a contact angle of 43 ° (25 ° C.) with the high-viscosity gel fluid 4 and a viscosity of 380000 mPa · s (25 ° C.). When the ballpoint pen tip 9 is turned upward or sideways, and when the environmental temperature rises, the high-viscosity gel-like fluid 4 filled in the ink cylinder 8 is maintained without the high-viscosity gel-like fluid 4 flowing out from the air holes 11a. Shall do.
The contact angle and the viscosity in this example can be adjusted by the composition of the high-viscosity gel-like fluid 4, the material of the ink cylinder 8, the surface condition of the wall surface, and the like, similarly to the example of the ink cartridge for the ink jet printer. The high-viscosity gel-like fluid 4 of this example is based on an α-olefin having an average molecular weight of 1250, is gelled by fine-particle silica and a dextrin fatty acid ester, imparts viscoelasticity, and has transparency.
[0021]
In the method for manufacturing the writing instrument of this example, after the floating body 10 is arranged in the axial direction by the guide portion 11b inside the tail plug 11 with the vent hole 11a facing downward, the floating body 10 is placed in the high-viscosity gel-like fluid 4, Fill so that it is partially immersed (FIG. 8). Next, with the vent hole 11a of the tail plug 11 facing upward, the tail plug 11 is fitted over the ink cylinder 8 filled with the ink 1 (not shown), and the container is closed. Thereafter, when a centrifugal treatment is performed, the high-viscosity gel-like fluid 4 moves toward the interface of the ink 1, and gas is removed from the vent 11 a of the tail plug 11, so that the container shown in FIG. 7 can be obtained.
[0022]
【The invention's effect】
As described above, according to the present invention, the interface between the content liquid and the follower fluid can be formed into a flat and stable shape, and the follower fluid does not follow with the consumption of the content liquid, or the layer of the follower fluid does not follow. It is possible to obtain a device that minimizes the problem that the content liquid leaks out over the wall.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing an example.
FIG. 2 is a cross-sectional view illustrating a manufacturing method.
FIG. 3 is a cross-sectional view illustrating a manufacturing method.
FIG. 4 is a sectional view corresponding to FIG. 2, showing another example.
FIG. 5 is a longitudinal sectional view showing another example.
FIG. 6 is a sectional view taken along line II ′ of FIG. 5;
FIG. 7 is a longitudinal sectional view showing another example.
FIG. 8 is a cross-sectional view illustrating a manufacturing method.
[Explanation of symbols]
REFERENCE SIGNS LIST 1 Ink 2 Tank body 2a Discharge port 2b Wall 3 Lid 3a Vent 3b Divided wall 4 High-viscosity gel-like fluid 5 Filter 6 Valve 6a Ink passage 7 Filling nozzle 8 Ink cylinder 9 Ballpoint pen tip 10 Floating body 11 Tail 11a Through Stoma 11b Guide

Claims (4)

It is composed of a container body having a discharge port and a lid having a ventilation hole, and contains, in a free state, a content liquid to be discharged from the discharge port to the outside in the container. A liquid storage container arranged in a layered manner so that the follower fluid having a specific gravity equal to or less than the value of the content liquid is not compatible with, and moves in accordance with the movement of the interface due to the volume decrease due to the discharge of the content liquid. A liquid storage container having a temporary follower fluid storage chamber whose body has a volume equal to or greater than the volume in which the follower fluid is stored. 2. The liquid container according to claim 1, wherein a contact angle θ between the follower fluid and the inner wall of the temporary follower fluid storage chamber is 30 ° <θ ≦ 90 °. The liquid container according to claim 1, wherein the viscosity of the follower fluid is not less than 10,000 mPa · s and not more than 2,000,000 mPa · s (25 ° C.). After filling the temporary follower fluid accommodating chamber of the lid with follower fluid, it is installed in the container body filled with the content liquid, and the centrifugal force is applied by rotating the lid with the ventilation hole positioned inside. 4. The liquid storage container according to claim 1, wherein an interface between the content liquid and the follower fluid is brought into contact, and gas interposed between the content liquid and the follower fluid is discharged to the vent hole side of the follower fluid. Production method.

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