JP2003053992A - Liquid container imparting negative pressure and ink jet recording head comprising it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid container having simple structure in which gas barrier performance or steam barrier performance is not damaged over a long term. SOLUTION: The liquid container for storing ink comprises a spring for imparting a negative pressure, a deformable sheet, a frame for securing the sheet while sustaining the shape, and a liquid supply opening for supplying ink to the outside wherein the outer surface of the frame is protected by a material exhibiting excellent gas barrier performance or steam barrier performance. Outer surface of the frame is protected by a multilayer film member formed by laminating and bonding a plurality of film members, and at least one layer of the multilayer film member is composed of a material exhibiting more excellent gas barrier performance or steam barrier performance than that of the frame material.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid use member connected to a liquid storage container such as a pen as a recording unit or an ink ejection unit, or a liquid storage container that uses negative pressure to supply liquid to the outside. The present invention relates to an ink jet recording head in which an ink tank as the liquid storage container and a recording head as a liquid using member are integrated.

[0002]

2. Description of the Related Art As a container for storing a liquid, there is known a container of a system for supplying the liquid while keeping the inside of the container at a negative pressure when the liquid is given to the outside. The characteristic of the container of this system is that the negative pressure given by the container itself can appropriately supply the liquid to a liquid using portion such as a pen tip or a recording head connected to the container.

For example, in the ink jet recording field in which the negative pressure characteristic is properly required, a sponge as a negative pressure generating source is stored in an ink tank as a liquid storage container, or a bag-shaped ink storage. A negative pressure is formed by providing a spring to the portion and applying a force against the inward deformation of the bag due to the consumption of ink (Japanese Patent Laid-Open No. 56-67269, Japanese Patent Laid-Open No. 6-226993, etc. (See) is known. In addition, a cone-shaped conical portion such as a rubber ink storage portion disclosed in U.S. Pat. No. 4,509,062 is formed, and the rounded conical portion is thinner than the conical peripheral surface thickness. There is also a configuration that does.

By the way, in the ink jet recording field using such a closed ink supply system, the following means are available as means for supplying the liquid to the portion using the liquid while maintaining an appropriate negative pressure. Conventionally known.

Generally, when the ink tank itself does not have a negative pressure source as the ink supply system, "head difference" is generated.
It is known that a negative pressure is maintained with respect to an ink using portion by a (pressure difference caused by a difference in height with respect to the ink using portion) to supply ink. In this case, an ink storage bag (also called an ink tank) does not require special conditions, and thus an ink storage bag such as a normal bag is often used.

However, since the ink supply system is a closed type as the ink supply path, a supply pipe such as a tube is required from the ink storage bag to the ink use portion (ink ejection head) located above, resulting in a large size. It becomes a device. Ink tanks have been proposed and implemented that can reduce or eliminate the water head difference in the ink supply path as much as possible and can apply a negative pressure to an ink ejection head (also referred to as a recording head). A device in which the ink discharge head and the ink tank can be integrated will be referred to as an inkjet cartridge.

The ink jet cartridge has a structure in which the recording head and the ink storage portion are always integrated, and the recording head and the ink storage portion are separate bodies, and both of them can be separated from the recording apparatus so that they can be integrated when used. It can be divided into the configuration to be used. In any of the configurations, in order to improve the use efficiency of the ink stored in the ink storage unit,
In many cases, the connecting portion of the ink containing portion with the recording head is provided below the center of the ink containing portion. Therefore, in order to stably hold the ink in the ink storage portion of the ink jet cartridge and prevent the ink from leaking from the ejection portion such as the nozzles provided in the recording head, it is necessary to prevent the ink from flowing to the recording head. A mechanism for generating pressure is required. This back pressure is called a negative pressure because it makes the pressure at the discharge port negative with respect to the atmospheric pressure.

As one of the easiest methods for generating a negative pressure, there is a method of utilizing the capillary force of a porous body. An ink tank to which the method is applied is a porous body such as a sponge housed in the entire ink tank for the purpose of storing ink, preferably compressed and housed,
In order to facilitate the ink supply during printing, the ink storage section includes an atmosphere communication port capable of taking in air.

However, a problem in using the porous member as the ink holding member is that the ink containing efficiency per unit volume is low. In order to solve this problem, a configuration in which the porous member is inserted into a part of the ink tank is used instead of the configuration in which the porous member is inserted into the entire ink tank. With this configuration, the ink storage efficiency and the ink holding capacity per unit volume can be increased as compared with the configuration in which the porous body is inserted into the entire ink tank.

From the viewpoint of further improving the ink storage efficiency, a bag-shaped container having a combination of a bag and a spring as described above, or a rubber ink storage container may be used.

[0011]

When the liquid storage container as described above is stored for a long period of time or left for a long period of time,
Since the inside of the ink tank has a negative pressure, gas such as oxygen and nitrogen permeates through the sheet or frame member, which is a material forming the ink tank, and mixes into the ink tank. At this time, since the open or semi-closed liquid storage container is partially communicated with the atmosphere, it is not necessary to consider the influence of the internal pressure rise of the liquid storage container due to long-term storage or fluctuation of atmospheric pressure. However, in a liquid container of a closed system, the internal pressure in the container increases with the inflow of gas, and when the pressure exceeds the meniscus pressure resistance on the ejection port side, the meniscus may be broken and lead to ink leakage from the ink ejection port. There is.

In particular, except for the flexible film which has been conventionally used in consideration of the gas barrier property, the materials used for the rigid structural members constituting the ink container and the recording head have little adverse effect on the ink and can be used as a sheet. In some cases, it is not possible to use a gas with a very good gas permeability from the option that welding is possible, and in this case, it is considered that the gas permeation from the rigid structural member is greatly related to the increase in the internal pressure inside the liquid storage container. To be

Further, when a sponge as a negative pressure generating source is housed inside the liquid container, a buffer material against an increase in internal pressure is generated due to gas entering the cells of the sponge as the amount of liquid inside decreases. However, in the liquid storage container constituted by the spring and the resin sheet, only the liquid is present, and considering that the liquid storage container is in the hermetically sealed state, the influence on the rise of the internal pressure in the container becomes remarkable.

In addition, in order to suppress an increase in the liquid concentration in the storage container, it is necessary to suppress the evaporation of water that permeates the members used in the liquid storage container.

In view of the above problems, it is an object of the present invention to provide a liquid container which has a simple structure and does not impair the gas barrier property for a long period of time.

[0016]

In order to achieve the above object, the liquid container of the present invention has a spring for applying a negative pressure, and a deformable sheet is fixed to the sheet,
A liquid storage container for storing ink, which has a frame for holding a shape and a liquid supply port for supplying ink to the outside, the outer surface of the frame being protected by a material having an excellent gas barrier property. It is characterized by

The outer surface of the frame is protected by a multi-layered film member in which a plurality of film members are laminated and bonded to each other, and at least one layer of the multi-layered film member has a gas barrier property superior to that of the material of the frame. It is preferably composed of a material.

Further, one layer serving as a joint surface of the multilayer film member with the frame may be made of the same material as the frame, and the multilayer film member may be joined to the frame by heat welding.
The multilayer film member made of a material different from that of the frame may be bonded to the frame by adhesion.

The outer surface of the frame may be composed of a single layer film member having an excellent gas barrier property.

Further, the liquid container of the present invention is mounted on an ink jet recording head.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments embodying the present invention will be described below with reference to the drawings.

(Ink Tank, Manufacturing Method Thereof and Ink Jet Recording Head) First, a manufacturing method of an ink tank as a liquid container according to the present invention and an ink jet recording head including the ink tank will be described.

FIG. 1 is a perspective view of an ink tank 127 manufactured according to the present invention, which is a rectangular frame 115.
The upper and lower openings of the upper and lower spring / seat unit 114
Has a sealed structure with attached. The spring / seat unit 114 includes the spring 107 and the pressure plate 10 as described later.
9 and a flexible tank sheet (flexible member) 106. The frame 115 has a first opening that communicates with the inside of the ink tank 127.
An ink supply port 128 and a second ink supply port 129 are formed.

2 to 6 are views for explaining a method of manufacturing such an ink tank 127.

First, FIGS. 2 (a), 2 (b) and 2 (c) are explanatory views of a process of molding the flexible tank sheet 106 into a convex shape.

The sheet material 101 as a forming material of the tank sheet 106 is formed from a raw material into a large size sheet, and the sheet material 101 occupies an important factor of ink tank performance. This sheet material 101 has low permeability of gas and ink components,
In addition, it is required to have flexibility and durability against repeated deformation. Suitable materials include PP, PE, PV
It may be DC, EVOH, nylon or the like, and as the composite material, a material such as aluminum or silica vapor-deposited may be used, and these may be laminated and used. Particularly, by stacking and using PP or PE having excellent chemical resistance and PVDC having excellent gas / water vapor barrier performance, excellent ink tank performance can be exhibited.
Further, the thickness of such a sheet material 101 is preferably about 10 μm to 100 μm in view of flexibility and durability.

Such a sheet material 101 is shown in FIG.
As shown in (a), the convex portion 103 and the vacuum hole 10
4 and a convex mold using a molding die 102 having a temperature adjusting mechanism (not shown). That is, the sheet material 101 is adsorbed to the vacuum holes 104, and the molding die 1
It is molded into a convex shape along the convex portion 103 by the heat from 02. The sheet material 101 is molded into a convex shape as shown in FIG. 2B, and then the tank sheet 1 is formed as shown in FIG.
It is cut out into a predetermined size as 06. The size may be any size suitable for the manufacturing apparatus in the next step, and can be set according to the volume of the ink tank 127 that stores the ink.

FIG. 3A is an explanatory view of the manufacturing process of the spring unit 112 used for making the inside of the ink tank 127 negative pressure. Spring 1 pre-formed in a semi-circle shape
07 is attached to the spring receiving jig 108, and from above,
Pressure plate 10 by spot welding using welding electrode 111
Attach 9. A thermal adhesive material 110 is attached to the pressure plate 109. The spring 107 and the pressure plate 109 form a spring unit 112.

FIG. 3B is an explanatory view of a process of attaching the spring unit 112 to the tank seat 106. The spring unit 112 is positioned and arranged on the inner surface of the tank seat 106 placed on a receiving jig (not shown). Then, the heat adhesive 113 is heated by using the heat head 113, so that the spring unit 112 and the tank sheet 106 are bonded to each other to form the spring / sheet unit 114.

FIG. 4A shows the spring / seat unit 11
It is explanatory drawing of the process of welding 4 to the frame 115. The frame 115 is fixed to the frame receiving jig 116. Sheet suction jig 117 surrounding the frame 115
After the frame 115 is positioned and arranged, the spring / seat unit 114 is adsorbed to the vacuum hole 117A to hold the unit 114 and the frame 115 relatively without displacement. Then, the heat head 118 heat-welds the annular joint surfaces of the peripheral edge portion of the frame 115 on the upper side in the drawing and the tank sheet 106 of the spring / seat unit 114. The sheet suction jig 117 makes the peripheral edge of the upper side of the frame 115 in FIG. 4A and the peripheral edge of the tank sheet 106 of the spring / seat unit 114 evenly face each other, so that the joint surface thereof is extremely high. It will be heat-welded and sealed uniformly. Therefore, the sheet suction jig 117 is important for heat welding so as to ensure uniform sealing.

FIG. 4B shows the tank sheet 1 protruding outside the frame 115 by a cutter (not shown).
It is explanatory drawing of the process of cutting out the part of 06. In this way, the spring seat frame unit 119 is completed by cutting off the portion of the tank seat 106 protruding from the frame 115.

FIGS. 5 and 6 (a) and 6 (b) show such a spring / seat / frame unit 119 in which another spring / seat unit 114 manufactured by the above-described process is manufactured.
It is explanatory drawing of the process of heat-welding.

As shown in FIG. 5, the spring seat frame unit 119 is attached to a receiving jig (not shown),
A suction jig 12 whose position is defined relative to the receiving jig 12
The outer periphery of the spring seat frame unit 119 is surrounded by 0. The receiving jig is in surface contact with the flat portion 106A of the outer surface of the tank seat 106 of the spring / seat / frame unit 119, and the flat portion 106A
Are held as shown in FIGS. 6 (a) and 6 (b). In the other spring / seat unit 114, the flat surface portion 106A of the outer surface of the tank seat 106 is suction-held by the pressing jig 121, and the pressing jig 121 is lowered,
The tip portion 1 of the spring 107 on the side of the spring / seat unit 114
07A and 107B and the tip portions 107A and 107B of the spring 107 on the side of the spring seat frame unit 119 are fitted substantially at the same time. That is, one tip portion 107A of the spring 107 has a convex shape and the other tip portion 107B has a concave shape so that they are fitted into each other by self-alignment. One spring member is configured by combining the components as a structure.

Further, the holding jig 121 is lowered to
As shown in FIG. 6A, the pair of springs 107 are compressed. At that time, the pressing jig 121 widely presses the flat portion 106A on the upper side in FIG. 5 of the spring / seat unit 114, that is, the flat region on the upper side of the tank sheet 106 formed on the convex portion. As a result, the position of the flat portion 106A of the tank seat 106 is regulated, and the spring / seat unit 114 approaches the lower unit 119 or the jig 120 while being kept in parallel. Therefore,
As shown in FIG. 6B, the peripheral edge portion of the tank seat 106 of the spring / seat unit 114 is in contact with the surface of the suction jig 120 and is suction-held in the vacuum hole 120A.
The welding surface of the frame 115 (the upper bonding surface in the figure) is evenly faced. And in this state,
By the heat head 122, the peripheral edge of the frame 115 of the spring / seat / frame unit 119 on the upper side in the drawing,
The tank seat 106 of the spring / seat unit 114,
The annular joint surfaces of are heat-welded to each other.

Thus, the flat portion 106A of the tank seat 106 of the upper unit 114 and the lower unit 1
The flat portions 10 of the pair of tank sheets 106 are compressed by compressing the pair of springs 107 while maintaining the parallelism with the flat portion 106A of the tank sheet 106.
The ink tank 127 having a high parallelism of 6 A can be stably mass-produced. In addition, a pair of springs 107
6 is uniformly compressed and deformed in the left and right directions in FIGS. 6A and 6B, a force that tilts the spring / seat unit 114 is not generated, and the parallelism of the flat surface portions 106A of the pair of tank seats 106 is reduced. It is possible to more stably produce the ink tank 127 having a high price. Further, as the volume inside the ink tank 127 changes, a pair of springs 10 is formed.
6 is compressed and deformed uniformly in the left and right in FIGS. 6A and 6B, the flat portion 106 of the pair of tank seats 106.
In A, the facing distance changes while maintaining high parallelism, and as a result, ink can be stably supplied. In addition, the flat portion 106 of the flexible tank sheet 106
Since an unreasonable force such as tilting A is not applied, the ink tank 127 has improved sealability, pressure resistance, and durability.

After that, the ink tank 127 of FIG. 1 is completed by cutting off the portion of the tank sheet 106 protruding to the outside of the frame 115. Ink tank 12
The inside of 7 has a sealed structure in which the first ink supply port 128 and the second ink supply port 129 communicate with the outside.

FIG. 7 is an explanatory diagram of a process of attaching the ink tank 127 to the recording head.

Head chip 133 constituting the recording head
Is attached to the ink tank storage chamber 130, and a plurality of ink tanks 127 are attached inside the ink tank storage chamber 130. The ink tank 127 is attached to the ink tank attachment portion 131 by welding or adhesion. Further, the ink tank 127 of this example is attached with the ink supply ports 128 and 129 facing downward. After that, the lid 132 is attached to the opening of the ink tank accommodating chamber 130 by welding or adhesion, and the ink tank accommodating chamber 13
The inside of 0 is a semi-closed space. Thus, the recording head including the ink tank is configured. The head chip 133 may constitute an inkjet recording head, and as the inkjet recording head, for example,
A configuration including an electrothermal converter for ejecting ink droplets from the ink ejection port can be adopted. In other words, it is possible to adopt a configuration in which the ink is film-boiling by the heat generation of the electrothermal converter and the bubbling energy is used to eject the ink droplet from the ink ejection port. An ink jet cartridge can be constructed by connecting such an ink jet recording head and an ink tank.

FIG. 8 is a cross-sectional view of the ink tank accommodating chamber 130 of FIG. 7 having an ink tank.

Ink can be stored inside the ink tank 127, and the ink is supplied from the first ink supply port 128 of the ink tank 127 to the supply path 136 via the filter 137 and further to the head chip 133. Supplied. In the head chip 133 of this example, a heater board 134 is bonded so as to form an ink jet recording head. The heater board 134 is provided with an ink discharge channel and an orifice, and an electrothermal converter (heater). ) Is provided, and the ink supplied from the ink tank 127 can be ejected. It is possible to fill the ink tank 127 with ink from the second supply port 129. That is, a joint seal 139 is fixed to the second supply port 129 by a joint seal plate 139 so as to prevent ink leakage and allow ink filling so as to seal the lower opening 141 of the tank storage chamber 130. Joint seal 13
The joint seal 138 is provided with a slit opening into which a needle-shaped supply pipe can be inserted. Ink tank 1
At the time of supplying the ink to the inside of 27, the needle-shaped supply pipe is inserted into the slit opening of the joint seal 138, and the ink is supplied into the ink tank 127 through the supply pipe. When ink is not supplied into the ink tank 127, ink is not leaked because the slit opening is closed by the elasticity of the joint seal 138. Reference numeral 140 denotes a communication passage communicating with the second supply port 129, which can be formed in advance inside the frame 115.

Further, the ink tank accommodating chamber 130, which has a semi-sealed structure by the lid 132, has a communication port 142 of a small hole.
It communicates with the outside only by. The inside of the ink tank storage chamber 130 is depressurized by blocking the inside of the ink tank storage chamber 130 from the atmosphere by closing the communication port 142 or discharging the air inside the ink tank storage chamber 130 from the communication port 142. It is possible to increase the negative pressure in the ink tank 127.

The second ink supply port 129 is obtained by repeating the pressure reduction and pressure increase in the ink tank accommodating chamber 130.
It is also possible to automatically suck and replenish ink into the ink tank 127. At that time, the ink tank storage chamber 13
Since the spring 107 elastically deforms with high responsiveness in response to a pressure change within 0, it can be suitably used as a small ink tank to which ink is frequently replenished.

Instead of the pair of springs 107, one spring having the same shape as when they are connected may be provided. In that case, the one spring is attached to one of the pair of tank seats 106, and then the tank seat 106 is attached.
It is also possible to couple the tank seat 106 to the frame 115 and then couple the other tank seat 106 to the frame 115 while compressing one spring thereof. At that time, 1
Instead of attaching one spring to one of the pair of tank seats 106, the spring may be simply sandwiched between the pair of tank seats 106.

At least one of the pair of tank sheets 106 may be formed of a flexible member.

(Example) The ink tank manufactured by the above manufacturing method is shown in FIG. 1 again, although it is also shown in FIG. The ink tank 127 shown in FIG.
It is composed of a deformable tank seat 106, a frame 115 and a spring unit 112. In this embodiment, polypropylene (PP) is used as the material used for the frame 115, but the material is not limited to this. As the frame material, in addition to PP, polyethylene (PE), a mixed material of PP and PE, noryl (PPO), polysulfone (PSF), for example, in terms of ink contact properties, material moldability, strength, and assemblability. , Acrylic, polystyrene (PS), and the like.

FIG. 10 shows an example of the film member 200 used for protecting the outer surface of the frame 115 from the viewpoint of suppressing gas permeation of the ink tank 127. A cross-sectional view of the multilayer film member is shown in FIG. 10 (a), and a cross-sectional view of the single-layer film member is shown in FIG. 10 (b).
Shown in.

As the constitution of the membrane member 200, at least one protective layer 201 made of a material excellent in gas barrier performance, that is, a material having low gas permeability, a layer 203 made of the same material as or a material different from the protective layer 201, and these two layers are used. And an adhesive layer 202 for adhering the two. Figure 1
0 (a) is a cross-sectional view of an example showing the configuration, and further includes a protective layer 201 and other layers 2 via an adhesive layer 202.
A configuration in which 03 are stacked is also possible. Further, it may be a multilayer film member having no adhesive layer such as a co-extruded film.

Further, for the purpose of improving the gas barrier performance, it is also possible to use a single protective layer 201 having a high gas barrier property as shown in FIG. 10B.

Materials used for the protective layer 201 include polyvinylidene chloride (PVDC), polyvinyl chloride (PVC), ethylene vinyl alcohol (EVO).
H), polyacrylonitrile (PAN), polyamide-based nylon, polyimide, and other materials with excellent gas barrier properties. As described above, since the tank sheet 106 forming the ink tank uses a material having an excellent gas barrier property, the tank sheet 106 is protected by the protective layer 20.
It may be adopted as 1.

Also, the layer 20 joined to the frame 115
As a material used in No. 3, in consideration of assemblability, P, which is a polyolefin-based material of the same material as the frame material, is used.
P, PE and nylon (N
Y) or polyethylene terephthalate (PET).

In the present embodiment, the reason for improving the gas permeability of the frame 115 is as follows.

Among the constituent materials of the ink tank 127, the literature values of the respective materials indicate that the oxygen permeability is P
P 1.70, PVDC 0.0038 [(cm ³ × cm) / (c
m ² × sec × Pa)]. In comparison of PP and PVDC, PP is expected to have a gas permeation that is 450 times that of PVDC. In this embodiment, the sheet 106 using PVDC or EVOH and the frame 115 using PP.
When the relative amount of the gas permeation amount is compared from the area and the thickness of the sheet, the gas permeation from the frame 115 is
It is 8 to 10 times that of the gas permeation from 06. A material having such a high gas barrier performance is used as the membrane member 2 of this embodiment.
00, by welding or adhering to the frame 115, the amount of gas permeation from the frame 115 can be suppressed to 10% or less of the current level.

Further, it is preferable that the above-mentioned constituent material is a material which, at the same time as the gas barrier property, prevents the ink from evaporating to the outside. By taking this evaporation into consideration, it is possible to obtain good characteristics with respect to the ink storability that the composition of the ink inside the ink tank is little changed over a long period of time. Regarding the water vapor permeability, PP is 51 and PVDC is 7 [(cm ³ × cm) / (cm ² × sec × Pa)] in literature values.

FIG. 11 shows the outer surface of the frame 115
This is an embodiment covered with a multilayer film member 200. In the figure, 140 is a supply / exhaust pipe for supplying ink into the ink tank and discharging the mixed gas in the ink tank.

12 and 13 show the steps of adhering and welding the multilayer film member 200 to the frame 115. 12 shows the case where the multilayer film member 200 is adhered or welded to the frame 115 as a single body before being assembled as an ink tank, and FIG. 13 shows the frame 11 of the ink tank 127 after being assembled as an ink tank.
5 shows a case where the multilayer film member 200 is adhered and welded.

In FIG. 12, the layer joined to the frame 115 is made of the same material as the frame 115. The multilayer film member 200 slightly wider than the frame width is placed horizontally with respect to the frame 115, and the heat head 150 is applied from above to heat-bond the horizontal portion of the frame 115 and the film member 200 (FIG. 12A). (See (b)). Next, the multilayer film member 200 and the heat head 150 are applied in parallel to one side surface of the frame 115, and similarly heat-welded (see FIG. 12C). Similarly, the multilayer protective member 200 and the heat head 150 are also applied to the other side surface in parallel and heat-welded (see FIG. 12D). Finally, the sheet protruding from the frame 115 is cut. Also in the case of FIG. 13, the multilayer film member 200 can be welded by the same process.

When a multi-layer film member having a material that cannot be heat-welded on the adhesive surface side to the frame 115 or a single-layer film member that is difficult to weld to the frame 115 is used, instead of heat welding, the frame 115 and An ink tank having a high gas barrier property can be assembled by bonding the film member 200 and the film member 200 with an adhesive.

FIG. 14 shows a case where the tank sheet 106 is used as the film member 200 as described above. The figure shows the ink tank immediately before cutting the sheet in the step shown in FIG. 6B, which is near the completion of the ink tank in the ink tank manufacturing process. As shown in FIG. 14, prior to coating the tank sheet 106 on the frame 115, the hatched portion 106-A (3 in the figure) of the sheet 106 in consideration of the gas barrier property (that is, high gas barrier property). Point) is cut.

FIGS. 15A to 15D show the sheet 106 in the process of manufacturing the ink tank shown in FIG.
Is shown to be heat welded. As shown in this figure, the sheet 106 remaining without being cut is heat-welded to each surface of the frame 115 by using the heat head 150, and the extra sheet 106 is cut. A desired ink tank can be manufactured.

In any case, the film member 200 is provided on the lower surface side frame 115 in which the first and second ink supply ports 128 and 129 of the ink tank are formed, as is clear from the configuration. No need to give. Also,
The order in which the film member or sheet is heat-welded to the frame is not limited to the order shown in the figure.

[0061]

As described above, by using a film having excellent gas barrier properties, it is possible to easily prevent gas contamination,
As a result, it is possible to suppress an increase in the internal pressure in the liquid container and, at the same time, to suppress evaporation, thereby suppressing an increase in the concentration of the liquid in the container.

[Brief description of drawings]

FIG. 1 is a perspective view of an ink tank of the present invention.

2 (a), (b), and (c) are explanatory views of a process of forming a tank sheet in the ink tank of FIG.

3A is an explanatory diagram of a manufacturing process of a spring unit in the ink tank of FIG. 1, and FIG. 3B is an explanatory diagram of a manufacturing process of a spring / sheet unit in the ink tank of FIG.

4A and 4B are explanatory views of a manufacturing process of the spring / seat / frame unit in the ink tank of FIG.

5A and 5B are explanatory views of a connecting process of the spring / seat unit and the spring / seat frame unit in the ink tank of FIG.

6 (a) and 6 (b) are cross-sectional views of a main part in the joining step of FIG.

FIG. 7 is an explanatory diagram of a mounting process of the ink tank of FIG.

8 is a cross-sectional view of a main part of the ink tank of FIG. 7 in a mounted state.

FIG. 9 is a perspective view of an ink tank according to the present invention.

10A and 10B are cross-sectional views of a film member having a low gas permeability applied to the ink tank according to the present invention, where FIG. 10A is an example of a multilayer film member, and FIG. 10B is an example of a single layer film member. Show.

FIG. 11 is a vertical sectional view of an ink tank according to the present invention.

FIG. 12 is one embodiment of the present invention, showing a step of attaching a film member to an ink tank according to the present invention before manufacturing the same, and FIG. 12A shows before attaching the film member to a frame constituting the ink tank. Is a perspective view for explaining the state of FIG. 5, (b) is a view showing a step of thermally welding the film member to the upper surface of the frame, (c)
FIG. 6A is a diagram showing a step of thermally welding the film member to one side surface of the frame next, and FIG. 8D is a diagram showing a step of subsequently thermally welding the film member to the other side surface of the frame.

FIG. 13 is another embodiment of the present invention, and is a perspective view illustrating a state in which the film member is attached to the ink tank according to the present invention after manufacturing.

FIG. 14 is a perspective view for explaining a state in which a film member is attached to the ink tank according to the present invention during the manufacturing thereof, which is still another embodiment of the present invention.

15 shows a step of thermally welding the film member to the frame in FIG. 14, (a) is a cross-sectional view taken along the line AA of FIG.
(B) is a figure which shows the process of heat-welding the membrane member (sheet) to one side surface of a frame from the state of (a), (c),
Next, the figure which shows the process of heat-welding the sheet to the other side surface of the frame, and (d) is the figure which shows the process of subsequently heat-welding the sheet to the upper surface of the frame.

[Explanation of symbols]

106 Tank sheet (flexible member) 106A flat part 107 spring 107A, 107B Tip 109 Pressure plate 110 thermal adhesive 112 spring unit 114 spring seat unit 115 frames 119 Spring seat frame unit 121 Holding jig 122 heat head 127 ink tank 128 1st ink supply port 129 Second ink supply port 130 ink chamber 133 head chip 150 heat head

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Nobuyuki Kuwahara             3-30-2 Shimomaruko, Ota-ku, Tokyo             Non non corporation (72) Inventor Tetsuya Ohashi             3-30-2 Shimomaruko, Ota-ku, Tokyo             Non non corporation F-term (reference) 2C056 EA26 KC14 KC18

Claims (9)

[Claims] 1. A spring having a negative pressure, a deformable sheet, a frame for fixing the sheet and holding a shape, and a liquid supply port for supplying ink to the outside. A liquid container for storing ink, wherein the outer surface of the frame is protected by a material having an excellent gas barrier property. 2. The outer surface of the frame is protected by a multi-layered film member in which a plurality of film members are laminated and bonded to each other,
The liquid container according to claim 1, wherein at least one layer of the multilayer film member is made of a material having a gas barrier property superior to that of the material of the frame. 3. The one layer serving as a bonding surface of the multilayer film member with the frame is made of the same material as the frame, and the multilayer film member is bonded to the frame by heat welding. Liquid storage container described. 4. The one layer serving as a bonding surface of the multilayer film member with the frame is made of a material different from that of the frame, and the multilayer film member is bonded to the frame by adhesion. Liquid storage container described. 5. The liquid container according to claim 1, wherein the outer surface of the frame is composed of a single-layer film member having an excellent gas barrier property. 6. The liquid container according to claim 1, wherein at least a part of the material having an excellent gas barrier property includes the same material as the sheet material. 7. The liquid container according to claim 1, wherein at least a part of an outer surface of the frame is covered with the sheet material itself. 8. An ink jet recording head comprising at least one liquid storage container according to any one of claims 1 to 7. 9. At least one of the liquid containers is
9. The ink container is mounted in the ink storage chamber.
The inkjet recording head according to 1.