JPH1044453A - Liquid container, head cartridge, and recorder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid container which can be produced easily at low cost while having high degree of freedom for altering the shape and in which a negative pressure can be generated in safety while enhancing the use efficiency. SOLUTION: An ink tank 100 has double wall structure of a tubular resin molded outer wall 101 and an inner wall 102 thinner than the outer wall 101. The ink tank 100 is provided, on one end face thereof, with a part 103 for feeding ink from the enclosed inner wall 102 to the outside of the tank. A pinch-off part 104 for forming an enclosed space is formed at one end of the inner wall 102. The inner wall 102 is also provided with a part 108, corresponding to the bent corner part around one end face of the outer wall 101, for promoting deformation of the inner wall at the time of delivering ink.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid storage container using a negative pressure to supply a liquid to an external member of a liquid storage container or to the outside, such as a pen or an ink discharge unit as a recording unit, and a liquid container. The present invention relates to a head cartridge integrated with a liquid ejecting head and a recording apparatus, and more specifically, to a field of ink jet recording to which an epoch-making ink tank for forming a liquid container itself by blow molding is applied.

[0002]

2. Description of the Related Art As a container for accommodating a liquid, there has been known a container for supplying a liquid while applying a negative pressure to the inside of the container when supplying the liquid to the outside. A feature of this type of container is that a proper liquid supply can be performed to a liquid using part connected to the container, such as a pen tip or a recording head, by a negative pressure applied by the container itself.

There are various types of such a theory that have been demonstrated in actual liquid storage containers, but the range of use of the various containers has been limited. This is because there is no manufacturing variation and there is no simple structure.

[0004] For example, in the field of ink jet recording which needs this negative pressure characteristic properly, there is a method in which a sponge as a negative pressure source is stored in an ink tank as a liquid storage container, or a bag of ink. Provide a spring in the storage section,
A device that forms a negative pressure by giving a force that resists inward deformation of a bag due to consumption of ink (Japanese Patent Application Laid-Open No. 56-67269,
Japanese Patent Application Laid-Open No. 6-226993) is known. The rubber ink container disclosed in U.S. Pat.No. 4,509,062 has a conical shape with a rounded conical portion, and the rounded conical portion is thinner than the thickness of the conical peripheral surface. It is a configuration of doing. The thin rubber bag structure with the rounded conical portion is a structure for the storage container to be preferentially displaced and deformed in accordance with ink consumption. These have been put to practical use as ink containers for ink jet devices, and are satisfactory at present.

However, since such a negative pressure generating structure is relatively expensive, it is not suitable for a writing implement having a pen tip such as a marker or a plotter. In particular, it is not preferable to have an extra complicated negative pressure generating structure as described above as a writing implement of this kind, because the writing implement itself becomes large in size.

[0006] Incidentally, the above-mentioned writing implement employs a form in which ink is supplied while air is introduced into the liquid storage container from the pen tip by using a felt capable of generating a negative pressure at the pen tip itself. ing. The biggest problem with the gas-liquid exchange structure in this ink supply mode is ink leakage from the pen tip. In order to solve this problem, as a mechanism for preventing ink leakage between the pen tip and the liquid storage container, a large number of fins are overlapped at predetermined intervals so as to intersect the ink supply direction, so that leakage due to environmental changes etc. It has been proposed to provide an ink holding mechanism that can hold ink to be ejected. However, at present, this mechanism leaves unusable ink inside the writing implement.

Further, the ink supply system of this type of writing implement is generally open to the atmosphere, which causes the stored ink to evaporate and reduce the amount of ink used. It is preferable to perform ink evaporation suppression as a typical closed type.

Here, the field of ink jet recording using a substantially closed type will be briefly summarized. Generally, when a negative pressure source is not used as the ink supply system,
2. Description of the Related Art There is known an ink supply unit that supplies ink by a difference in elevation with respect to an ink using unit (ink ejection head) called a “head difference”. In this case, since no special conditions are required for the ink storage unit, an ink storage bag such as a normal bag is often used.

However, since the ink supply path is of a sealed type, a supply pipe such as a tube is required from the ink storage bag to an ink use section (ink discharge head) located above, resulting in a large-sized apparatus. Would. In order to minimize or eliminate the head difference in the ink supply path, an ink tank for applying a negative pressure to the ink ejection head has been proposed and implemented. The one in which the head and the ink tank can be integrated will be referred to as a head cartridge.

The head cartridge can be further classified into a structure in which a recording head and an ink container are always integrated, a structure in which a recording unit and an ink container are separate, and both can be separated from a recording apparatus. It can be divided into a configuration to be used integrally.

In any of the configurations, in order to increase the efficiency of use of the ink stored in the ink storage section, the coupling section of the ink storage section with the recording means is often provided below the center of the ink storage section. For this reason, in order to stably hold the ink in the ink storage section of the head cartridge and to prevent ink leakage from a discharge section such as a nozzle provided in the recording section, the back pressure against the ink flow supplied to the recording section is reduced. Is required. This back pressure is called negative pressure because the pressure at the discharge port is made negative with respect to the atmospheric pressure.

One of the easiest methods for generating a negative pressure is a method utilizing the capillary force of a porous body as described above. The ink tank in the method is
Stored inside the ink tank for the purpose of storing ink,
Preferably, the ink jet recording apparatus includes a compressed and stored porous body such as a sponge, and an air communication port through which air can be introduced into the ink storage section to smoothly supply ink during printing.

However, a problem when using a porous member as an ink holding member is that the ink storage efficiency per unit volume is low. In order to solve this problem, a configuration in which a porous body 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 per unit volume and the ink holding capacity 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-like container having a combination of a bag and a spring as described above, or a rubber ink container can be used.

[0015]

With the current ink tanks as described above, the demands of the current market are at a satisfactory level.

However, the present inventors considered the ideal conditions required for a liquid container, particularly an ink jet ink tank, from the perspective of the future prospects.
I came up with the following three issues.

The first point is that the ink storage efficiency is further improved (first problem). That is, by further increasing the ink storage efficiency of the ink tank occupying the same space,
This is to increase the ink storage capacity of the ink tank.

The second point is that the number of constituent parts is small and the structure of the parts themselves is simple (second problem). Further, as additional effects, reduction in product yield, cost reduction,
Advantages such as reduction of quality control items can be expected.

However, an ink tank containing a porous member cannot be sufficiently satisfied in terms of ink storage efficiency as described above. Further, even with the current configuration using a bag-shaped container, a device having a complicated mechanism such as a spring inside the ink storage unit or between the ink storage unit and the housing uses a complicated mechanism. Not only is the cost high, the number of parts is large, and the assembly is complicated, but also the bag-like container has a multilayer structure to achieve both flexibility and prevention of ink evaporation.
The above issues are not satisfactory.

In the above-mentioned conical rubber ink container, since the structure limitation as described above is important,
It is not possible to provide a maximum space in the desired space. In addition, the kind of ink that can be used is restricted from a material viewpoint. Therefore, the conical rubber ink storage bag has a complicated structure and manufacturing conditions, is complicated in terms of quality control, and has a poor product yield.

An object of the present invention is to provide a liquid container capable of supplying a liquid while utilizing a stable negative pressure, as one of the components of the liquid supply system.

Another object of the present invention is to provide a negative pressure type liquid storage container which is inexpensive, can make maximum use of a given liquid storage space, has very little quality variation, and is excellent in environmental measures. It is to be.

Another object of the present invention is to achieve a negative pressure generation method which has not been available in the past, to a practical level, and to achieve a superior liquid supply performance while having a simple structure or operation, and to provide a negative pressure type liquid storage container. It is to provide.

Another object of the present invention is to provide a liquid storage container which can be downsized by utilizing a negative pressure in a liquid supply system based on a head difference.

Each of the objects of the present invention can be applied to a writing instrument and an ink jet recording head in the recording field, and another object in the ink jet field of the present invention is that the ink jet head can be completely integrated with or separated from the ink jet head. It is to provide a liquid storage container.

In addition, the remaining object of the present invention is to provide each of the inventions described below, such as a step invention and an apparatus invention in which the function of the liquid container is clarified in a method.

[0027]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention relates to an inner wall forming a liquid storage portion for storing a liquid therein, and an inner surface having a shape similar to or similar to the outer surface of the inner wall. A liquid container having an outer wall having a communication portion, a liquid supply unit for supplying liquid from the liquid storage unit to the outside, and a pinch-off portion in which a part where the inner wall is integrated is sandwiched by the outer wall. The resin forming the inner wall and the outer wall is substantially non-stretched, and the inner wall has a surface portion that can be moved substantially in parallel while substantially maintaining the shape, and the pinch-off portion exists on the surface portion. It is characterized by the following.

According to the present invention, there is further provided an inner wall forming a liquid storage portion for storing a liquid therein, an outer wall having an inner surface having a shape similar to or similar to the outer surface of the inner wall, and a substantial air communication portion,
A liquid storage container having a liquid supply unit that supplies liquid to the outside from the liquid storage unit, and a pinch-off unit in which a part where the inner wall is integrated is pinched by the outer wall,
The inner wall has a surface portion that moves while maintaining a substantially shape in response to a pressure change in the inner wall due to the discharge of the liquid, and the pinch-off portion is present on the surface portion.

According to the present invention, there is further provided an inner wall forming a liquid storage portion for storing a liquid therein, and an outer wall having an inner surface having a shape similar to or similar to the outer surface of the inner wall and a substantial air communication portion,
A liquid storage container having a liquid supply unit that supplies liquid to the outside from the liquid storage unit, and a pinch-off unit in which a part where the inner wall is integrated is pinched by the outer wall,
A structure that satisfies the relationship that a force that buckles the other surface of the inner wall requires a larger force than a force that deforms one of the surfaces of the inner wall having the pinch-off portion while maintaining the shape. It is characterized by.

Any of the above can solve the problem of the liquid storage container using negative pressure to supply a liquid to the outside such as a pen or a liquid discharge unit as a recording unit, and more preferable conditions will be mentioned. The details will be described later, but are as follows.

The liquid container has a cylindrical shape, and the surface portion (or one of the surfaces having the pinch-off portion of the inner wall) is located at one end surface of the cylinder, and the liquid supply portion is the surface portion (or The inner wall has one of the surfaces facing the pinch-off portion), and the inner wall has another thickness around the surface portion (or one of the surfaces having the pinch-off portion of the inner wall). The inner wall surface (or one of the surfaces of the inner wall having a pinch-off portion), and the inner wall surface portion (or the inner wall pinch-off portion). Preferably, one of the surfaces has two or more pinch-off portions.

The liquid container of the present invention is applied to a head cartridge and a recording apparatus particularly in the field of ink jet recording.

In the invention configured as described above, when the liquid in the inner wall is led out of the container, the surface of the inner wall moves in parallel to the opposite surface while maintaining its shape. With this deformation movement, the pressure in the inner wall decreases and a negative pressure is generated. Finally, the elastic force of the inner wall is balanced with the negative pressure, and the liquid cannot be drawn out any more in a normal use state. As a result, the surface reaches the opposing surface while maintaining the shape of the initial state, so that a stable negative pressure can be generated and maintained.

In particular, according to the present invention, the liquid storage container preferably has a cylindrical shape, the surface of the inner wall is located at one end of the cylinder, the liquid supply unit is provided on a surface facing the surface, and the surface of the inner wall is provided. In the case of having a deformation promoting portion whose thickness is thinner than the others, having a rib on the surface of the inner wall, and having two or more pinch-off portions on the surface of the inner wall, Acts like

That is, when the liquid is led to the outside of the container, the surface of the inner wall is deformed starting from the deformation promoting portion having a smaller thickness than the others, and a negative pressure is generated in the inner wall with this deformation. In addition, a pinch-off portion located on the surface of the inner wall facing the surface of the liquid supply unit is separated from the outer wall. At this time, since the pinch-off portion has a length component, the direction in which the pinch-off portion is deformed is restricted to a direction in which the surface portion moves substantially in parallel. Thereafter, the surface portion of the inner wall moves toward the liquid supply portion while bending at the deformation promoting portion while maintaining its shape. Here, only the deformation promoting portion bends because the surface adjacent to the surface portion of the inner wall corresponds to the side surface of the cylinder that is difficult to deform and buckle. Finally, the elastic force of the inner wall and the negative pressure are balanced, and the liquid cannot be discharged any more in a normal use state.

Thus, in the present invention, the liquid supply portion is formed in the process of consuming the liquid because the deformation promoting portion of the inner wall moves on the cylindrical side surface which is the surface adjacent to the surface portion of the inner wall. In the vicinity of the surface, a state in which almost no liquid remains can be created, and furthermore, the surface of the inner wall facing the liquid supply unit reaches the surface where the liquid supply unit is formed while maintaining the shape of the initial state, Stable negative pressure can be generated and maintained.

[0037]

Embodiments of the present invention will be described below with reference to the drawings.

(First Embodiment) Here, an ink tank for storing ink, which is applicable to an ink jet head for discharging ink for recording, will be described as an example of a liquid storage container. The ink tank according to the present embodiment has a cylindrical shape and adopts a double-walled structure made of a molding resin material, and maintains the shape of the end face facing the ink supply unit when the volume of ink contained in the sealed inner wall fluctuates. It is possible to generate and maintain a stable negative pressure by causing the vehicle to follow in a state in which the pressure is maintained.

FIG. 1 is a view for explaining a schematic configuration showing a first embodiment of a liquid container according to the present invention.
(A) is a cross-sectional view, and (b) is a side view of the end face facing the ink supply unit.

The ink tank 10 of the present embodiment shown in FIG.
0 is a cylindrical outer wall 101 made of molding resin, and
It has a double structure of an inner wall 102 which is thinner than the outer wall 101. The ink is stored in an ink storage unit that is a region surrounded by the inner wall 102. Further, the outer wall 101 protects the ink container so that the ink stored in the ink container does not leak to the outside due to inadvertent deformation of the inner wall.

Reference numeral 103 denotes an ink supply section from the inside of the container to the outside, and serves as a connection portion with an ink introduction section (not shown) on the ink jet head side.

The corners around one end of the ink tank are bent, and the inner wall 102 has bent corners corresponding to the bent corners around the one end of the outer wall 101.
The bent corners of the inner wall 102 serve as triggers for deformation of the inner wall when the ink is led out of the tank.
08, so the wall thickness is smaller than the other wall thicknesses. The thickness of the deformation accelerating portion 108 can be reduced naturally by forming a bent portion by blow molding, which will be described later, in order to make it thinner than the other thicknesses.

In the ink tank of this embodiment, in the initial state, the side of the inner wall corresponds to the side of the outer wall.
And the ink tank inner wall 102 can be made to follow the shape of the ink tank outer wall 101 almost in close contact with the shape of the ink tank outer wall 101, so that the ink storage amount per unit volume in the ink tank outer wall is increased (the ink storage efficiency is increased). Do)
be able to.

Reference numeral 104 denotes a pinch-off portion for forming an enclosed space by the inner wall 102. This pinch-off part 10
Numeral 4 is formed by sandwiching a parison for forming the wall of the ink tank with a mold at the time of blow molding to be described later. The inner walls 102 are welded to each other and engage with the outer wall 101. Since they are in close contact with each other, they are also used as supporting portions for supporting the inner wall 102 as described later.
The pinch-off section 104 is formed on both end faces of the ink tank as shown in FIG. 1B, and the ink supply section 103 is present on one end face side.

In this embodiment, a small gap 107 between the outer wall and the inner wall, which is formed in the vicinity of the pinch-off portion 104 and has a size of about several tens of μm, is used as an air intake. This gap applies an external force to the pinch-off portion 104 by selecting a material having low adhesion to the outer wall 101 for the inner wall 102,
It is easily formed by peeling the inner wall 102 from the outer wall 101.

Reference numeral 106 denotes an ink lead-out permitting member having a function of preventing ink leakage from the ink supply unit when a slight vibration or external pressure is applied to the tank, which serves as a connection portion with the ink jet head. In the present embodiment, a rubber stopper is used, and the structure has a meniscus holding force. The ink lead-out permitting member 106 substantially seals the ink containing part, and when the ink introduction part on the side of the inkjet head is inserted, the ink inside the ink containing part can be led out while maintaining the airtight state.

Depending on the combination of the ink tank 100 and the ink jet head, a porous member, a valve, a filter, a resin, or the like may be used instead of the rubber stopper at the location of the ink lead-out permitting member 106.

Here, the state change of the inner wall when ink is stored in the ink storage section of the ink tank and the ink is drawn out from the ink supply section will be described. FIG. 2 shows a state in which the liquid in the liquid container of the present invention is consumed.
(A) shows the start of derivation, (b) shows the middle, and (c) shows the end.

In the initial state, as shown in FIG. 1 (a), the inner wall and the outer wall are in close contact with each other, and the storage portion formed by the inner wall is filled with ink. When the ink in the inner wall is led to an external member (for example, an ink jet head) from this state, as shown in FIG.
8, the pinch-off portion 104 on the end face facing the ink supply portion 103 comes off the outer wall 101. Further, with this deformation, the pressure in the inner wall 102 decreases, and a negative pressure is generated. Here, since the pinch-off portion has a length component, the direction in which the pinch-off portion is deformed is restricted to a direction in which the surface moves substantially in parallel. After that, as shown in FIG. 2B, the deformation promoting portion 108 bends along the side surface of the inner wall 102 while the end face facing the ink supply portion 103 keeps its shape. Move towards. Here, only the deformation promoting portion 108 bends along the inner surface of the outer wall 101 because the side surface of the inner wall 102 is deformed.
This is because the cylindrical shape does not easily buckle. This form is
From another point of view, the end face facing the ink supply unit 103 satisfies the relationship that a force that buckles the side face requires a larger force than a force that moves while maintaining its shape. .

Then, as shown in FIG. 2C, finally, the elastic force of the inner wall is balanced with the negative pressure, and the ink cannot be discharged any more in a normal use state.

As described above, in this embodiment, in the process of consuming ink because the deformation promoting portion 108 of the inner wall 102 moves on the side surface of the inner wall 102, the transferred downstream side, that is, the ink supply portion 103 is formed. A state in which almost no ink remains in the vicinity of the end face, and furthermore, the end face facing the ink supply section 103 reaches the end face where the ink supply section 103 is formed while maintaining the shape of the initial state. It is possible to generate and maintain a negative pressure.

Next, a method for manufacturing the liquid container of the present embodiment will be described in detail.

In the present embodiment, blow molding using blowing air is employed as a method of manufacturing an ink tank. This is because the outer wall and the inner wall constituting the ink tank are made of a resin which is not substantially stretched, whereby the inner wall of the ink tank constituting the ink container is subjected to a substantially uniform load in any direction. I have to endure. Therefore, even if the ink contained in the ink tank inner wall oscillates in any direction while the ink is consumed to some extent, the ink tank inner wall can reliably hold the ink, and the overall ink tank durability can be improved. Have improved.

As the blow molding method, there are a method using an injection blow, a method using a direct blow, a method using a double wall blow, and the like. Here, the direct blow molding is used as an example, and FIGS. 3 and 4 are referred to. I will explain.

FIGS. 3A to 3D are views showing an example of a manufacturing process of the liquid container of the present invention, and FIG. 4 is a flowchart showing a manufacturing procedure of the liquid container of the present invention.

In FIG. 3, reference numeral 201 denotes a main accumulator for supplying the inner wall resin, reference numeral 202 denotes a main extruder for extruding the inner wall resin, reference numeral 203 denotes a sub-accumulator for supplying the outer wall resin, and reference numeral 204 denotes a sub-extruder for extruding the outer wall resin. It is.

First, an injection nozzle is used as a multi-layer nozzle, and an inner resin and an outer resin are simultaneously injected into a mold to prepare an integrated first and second parison.
In this case, the supply of the resin may be such that the inner resin and the outer resin are in contact with each other, or not all of them need to be in contact with each other.
Further, a structure in which a part of the resin is in contact may be used. In this case, the surface where the inner resin and the outer resin come into contact can be separated by selecting a material that does not weld the resins, or by adding a compound to one of the resins when supplying to the mold It is necessary to mold it. When the same type of material is required depending on the liquid contact property and the shape with respect to the ink, the resin may be supplied such that the inner material or the outer material has a multilayer structure so that different materials are located on the contact surface. .

It is ideal that the supply of the inner resin is uniform over the entire circumference. However, the resin may be partially thinned so as to easily follow the fluctuation of the internal pressure. In the present embodiment, the ink supply unit 10
The deformation promoting portion 108 was formed by bending the periphery of the end face facing the end face on which No. 3 was formed. The method of partially reducing the thickness is selected depending on the internal structure of the ink tank, but the configuration is in accordance with the supply direction of the resin supplied into the mold.

The supplied outer wall resin and inner wall resin are supplied to the die 206 via the ring 205 (steps S301, S302), and the parison 207 in which the first and second parisons are integrated is formed (step S301). Step S303). Next, a mold 208 arranged so as to sandwich the parison 207 integrated with the parison 207 is shown in FIG.
The parison 207 is sandwiched by moving from the state shown in FIG. 3B to the state shown in FIG. 3C (step S30).
4).

Subsequently, as shown in FIG. 3C, air is injected from the air nozzle 209 to blow-mold into a shape suitable for the mold 208 (step S305). At this time, the inner wall and the outer wall are in close contact with no gap. In addition, it is more preferable that the temperature of the mold is controlled within a range of about ± 30 ° C. with respect to the reference temperature at the time of molding because variation in individual thickness of each wall of the ink tank at the time of manufacturing can be reduced. .

Next, the inner and outer walls other than the ink supply section are peeled off (step S306). As a method of separating the inner wall and the outer wall other than performing the evacuation, there is a method of using materials having different thermal expansion rates (shrinkage rates) for the molding resin forming the inner wall and the outer wall. In this case, after the blow molding, the temperature of the molded product decreases, so that the molded product can be automatically peeled, and the number of steps can be reduced. Similarly, during blow molding, an external force is applied to the part sandwiching the parison between the molds after molding to separate the inner wall and the outer wall, and the gap is communicated with air, which can be used as an atmosphere communication port. Is more preferable because the number of steps can be reduced.

After the inner wall and the outer wall are separated as described above, ink is injected (step S307). At this time, before the ink is injected, the ink container may be made to have substantially the same shape as the initial state by the pressurized air, and then the ink may be injected. Further, when the ink container is formed in the same shape as the initial state, the ink may be injected by pressurization.

Further, when the amount of the ink to be injected is about 90% of the volume of the ink container, it is possible to easily cope with a change in the environment in which the ink tank is placed. Of the ink can be prevented from leaking to the outside from the change. After the ink is injected, the ink lead-out permission member is attached (step S3).
08).

In the above blow molding, since the parison 207 is processed in a viscous state, neither the inner wall resin nor the outer wall resin has orientation.

Further, assuming that the thicknesses of the inner wall resin and the outer wall resin before blow molding are t and T, the thicknesses t ₁ and T ₁ after blow molding.
Is processed to be thinner than the thicknesses t and T. The relationship between the thickness of the outer wall resin and the thickness of the inner wall resin is T> t from the point of the present invention.
It was formed so that T ₁ > t ₁ .

In this embodiment, the use of blow molding not only reduces the number of manufacturing steps and improves the yield due to the reduction in the number of parts, but also as shown in FIG. The shape of the inner wall 102 can be made along the shape of 101.

That is, in the initial state where the ink is filled,
Ink tank inner wall 10 with respect to ink tank outer wall 101
2 has a similar shape, and the ink tank inner wall 102 can follow the shape of the ink tank outer wall 101 serving as a housing at a predetermined range of intervals, so that the ink storage amount per unit volume in the ink tank outer wall is increased ( Ink storage efficiency).

Next, the molding resin constituting the ink tank of the present embodiment will be described.

The ink tank of this embodiment has a double structure of an inner wall for storing ink and an outer wall covering the inner wall. Therefore, the inner wall is preferably made of a material which is flexible when thinned, has excellent liquid contact properties, and has a low gas permeability, and the outer wall is preferably made of a material which is strong to protect the inner wall. It is.

Accordingly, the ink tank was molded using a polypropylene resin, a polyethylene resin, or a noril resin as a molding resin. Here, the noril resin is amorphous having almost no crystal structure, and the polypropylene resin and the polyethylene resin have crystallinity. Non-crystalline resins generally have low heat shrinkage, and crystalline resins generally have high heat shrinkage.

As the amorphous material, polystyrene, polycarbonate, polyvinyl chloride and the like can be mentioned as plastics. In addition, examples of the crystalline material include those that form a crystal part at a certain ratio under a predetermined environment for crystallization, and include polyacetal and polyamide.

The crystalline plastic has a relatively clear melting point such as a glass transition temperature (Tg: a temperature at which a molecule starts micro-Brownian motion and a property changes from a glassy state to a rubbery state). On the other hand, in the case of amorphous plastic, a glass transition temperature is present but no clear melting point is shown.

Plastics have a sudden change in mechanical strength, specific volume, specific heat, coefficient of thermal expansion and the like at the glass transition temperature and melting point. Therefore, by selecting a combination of materials utilizing this property, the resin on the inner side and the outer side can be selected. Can be improved. This example uses an amorphous noril resin on the outer side and a polypropylene resin on the inner side as in the first embodiment described above, and has a mechanical strength on the outer side, In addition, soft materials with large heat shrinkage can be selected.

Further, the polymer molecule has a C—C bond and a C—C bond.
In the case of a hydrocarbon structure consisting only of H bonds, it is called a nonpolar polymer. On the other hand, a polymer containing a large number of polar atoms such as O, S, N, and halogen is called a polar polymer, but the polar polymer has a large intramolecular condensing force and a large bonding force to the resin.

Utilizing this property, nonpolar resins
By combining a non-polar resin and a polar resin, it is possible to improve the releasability of the resin.

(Second Embodiment) Here, when the end face of the inner wall facing the end face on which the ink supply portion is formed is directed toward the ink supply portion when the ink is led out of the ink tank of the above-described embodiment, the end face is The means for maintaining the shape will be described with an example.

FIGS. 5 to 7 are side views of the second embodiment of the liquid container according to the present invention, as seen from the end face facing the ink supply section. In this figure, the same components as those in the first embodiment are denoted by the same reference numerals. As shown in FIG. 5, the pinch-off portion 1 of the inner wall 102 engaged with the outer wall 101
04a has a cross shape. Thereby, the inner wall 10
Since the one end surface of the inner wall 101 is not easily deformed, the shape of the one end surface of the inner wall 101 toward the ink supply unit at the time of drawing out the ink can be maintained. The shape of the pinch-off portion 104a is not limited to the cross shape as shown in FIG. 5 and may be any shape as long as the shape can be maintained, and a plurality of pinch-off portions 104a may be formed. The range which can be manufactured by the blow molding used is more preferable.

Also, as shown in FIG. 6, a rib 109 having a convex or concave shape is formed at the end face of the outer wall 101 and the inner wall 102 facing the ink supply portion 103 at the time of blow molding, so that the ink supply of the inner wall 102 can be performed. The portion of the end face facing the portion 103 becomes rigid, so that the shape toward the ink supply portion 103 when the ink is derived can be maintained.

Further, as shown in FIG. 7, the end surfaces of the outer wall 101 and the inner wall 102 facing the ink supply portion 103 are formed into curved portions 110 at the time of blow molding, whereby the inner wall 102 is formed.
Of the end face facing the ink supply unit 103 becomes rigid, and the shape toward the ink supply unit 103 when the ink is derived can be maintained.

Also in the above-described configurations shown in FIGS. 5 to 7, the force for buckling the side surface requires a larger force than the force for moving the end face facing the ink supply unit 103 while maintaining its shape. It has a structure that satisfies the relationship. If this relationship is satisfied, any or all of the configurations in FIGS. 5 to 7 may be appropriately combined.

(Other Embodiments) The liquid storage container of each of the above-described embodiments employs a cylindrical shape whose side surface is hardly deformed (buckled) due to internal pressure fluctuation.
It is more preferable to form the shape of a truncated cone in which the side surface of the cylinder is tapered so that the bottom surface on the supply port side becomes slightly larger, since the side surface of the inner wall is easily turned back along with the movement of the surface having the pinch-off portion.

Further, since the side surface of the inner wall is hardly deformed (buckled) due to the internal pressure fluctuation, and is easily turned back along with the movement of the surface having the pinch-off portion, the thickness distribution of the inner wall can be controlled by, for example, the supply port. It may be configured such that the thickness increases as approaching the side.

The liquid container may be used in accordance with various purposes, such as a liquid container integrated with an ink jet head described later or a liquid container relatively replaceable with the ink jet head. It can be applied to any of them.

In each of the above embodiments, the ink tank has been described as an ink tank in the field of ink jet recording. However, for example, a liquid is supplied to an external member of a liquid container such as a pen as a recording unit or an ink ejection unit or the like. Therefore, it is needless to say that the present invention can be applied to a liquid storage container using a negative pressure. In this case, the liquid supply unit corresponding to the ink supply unit of the ink tank may be provided with a liquid outflow prevention member that is an ink lead-out permission member in the ink tank.

Next, a case where the ink tank according to the first embodiment of the present invention shown in FIG. 1 is connected to a recording head will be described. FIG. 8A is a schematic view of a recording head which is recording means connectable to the ink tank according to the first embodiment of the present invention, and FIG. 8B shows a connection state between the recording head and the ink tank. FIG.

In FIG. 8A, reference numeral 401 denotes a recording head unit as recording means. The recording head unit (liquid ejecting head) 401 includes a liquid flow path having an ejection port for ejecting ink, A heating resistor element for discharging ink from the ink discharge port. Reference numeral 402 denotes an ink supply tube as an ink introduction unit for introducing ink into the recording head unit. At the end of the ink supply tube 402, a filter 403 for trapping bubbles and dust is provided. . A plurality of ink supply tubes 402 and filters 403 are provided so that full-color printing can be performed.
The recording head for each color of magenta may be assembled so as to have an integrated configuration.

When the above-described ink tank 100 is mounted on the recording head unit 401, FIG.
As shown in FIG.
The ink can be supplied by being connected to the ink lead-out permitting member 106 provided at 00.

After the ink tank is mounted, the ink inside the ink tank is introduced into the recording head by the recovery means or the like provided in the recording apparatus (not shown), and the ink communication state is formed. Thereafter, during the printing operation, ink is ejected from the ink ejection unit 404 provided in the recording head according to the recording signal, and the ink held in the ink tank inner wall 102 is consumed.

Further, the ink tank in each of the embodiments has a negative pressure generating and negative pressure holding capability in an inner package surrounded by the inner wall of the ink tank. It is sufficient that the ink lead-out permission member such as a stopper can hold ink when separated from the recording head.

Lastly, a description will be given of an ink jet recording apparatus which carries out recording by mounting the ink tank according to the first embodiment of the present invention shown in FIG. FIG. 9 shows the first embodiment of the present invention.
1 is a schematic diagram of an ink jet recording apparatus equipped with an ink tank according to the embodiment.

In FIG. 9, the head cartridge including the head unit 401 and the ink tank 100 is
The carriage is fixedly supported by a positioning means (not shown) on the main body of the inkjet recording apparatus, and is detachably mounted on the carriage.

The forward / reverse rotation of the drive motor 513 is transmitted to the lead screw 504 via the drive transmission gears 511 and 509 to rotate the lead screw 504, and the carriage is rotated by a pin (not shown) engaged with the spiral groove 505 of the lead screw 504. )
Having. Thereby, the carriage is reciprocated in the longitudinal direction of the apparatus.

Reference numeral 502 denotes a cap for capping the front surface of the recording head in the recording head unit, and is used for performing suction recovery of the recording head through an opening in the cap by a suction unit (not shown). The cap 502 can be moved by the driving force transmitted via the gear 508 and the like to cover the ejection opening surface of each recording head. Cap 50
In the vicinity of 2, a cleaning blade (not shown) is provided, and this blade is supported movably in the vertical direction in the figure. The blade is not limited to this form, and it goes without saying that a known cleaning blade can be applied to this embodiment.

The capping, cleaning, and suction recovery are configured so that desired operations can be performed at the corresponding positions by the action of the lead screw 505 when the carriage moves to the home position.
If a desired operation is performed at a known timing, any of the embodiments can be applied.

The connection pad 452 of the recording head unit mounted on the carriage is connected to the connection pad 531 when the connection plate 530 provided on the carriage is rotated around a predetermined axis, and is electrically connected. . Since no connector is used for this connection, no unnecessary force acts on the recording head.

[0096]

As described above, the liquid container of the present invention has an inner wall, an outer wall having an outer shape closely contacting the inner wall, a pinch-off portion which is engaged with the outer wall on the inner wall, and further comprises an outer portion of the container. With a structure that has a surface that moves while maintaining its shape in accordance with the pressure fluctuations in the inner wall when the liquid is led to the liquid, stable liquid derivation and negative pressure holding can be realized. .

Further, the liquid use efficiency can be improved by making the liquid supply portion for connection with the outside of the container face the surface of the inner wall.

Further, since there is no need for an absorbing member for generating a negative pressure in the container, there is no liquid selectivity and the liquid storage capacity can be increased.

In addition, since the number of parts of the container is reduced, the number of quality control items is reduced, the manufacturing process of the container is simplified, and accuracy from a practical point of view at the time of manufacturing the container can be easily satisfied. It is possible to provide a liquid storage container with low cost and high yield.

Further, since the liquid container is manufactured by blow molding, the inner and outer walls are more excellent in hermeticity than the container such as an ink tank manufactured by welding or adhering a plurality of ordinary parts, and the inner wall of the inner container is formed. By increasing the thickness, it is possible to prevent the ink from evaporating and make the ink more excellent in deterioration during long-term storage.

[Brief description of the drawings]

FIG. 1 is a view for explaining a schematic configuration showing a first embodiment of a liquid container according to the present invention, wherein FIG. 1 (a) is a cross-sectional view, and FIG. 1 (b) is a view of an end face facing an ink supply unit. FIG.

FIGS. 2A and 2B show a state in which the liquid in the liquid container according to the present invention is being consumed. FIG.
Indicates the end respectively.

FIG. 3 is a diagram illustrating an example of a manufacturing process of the liquid storage container of the present invention.

FIG. 4 is a flowchart showing a manufacturing procedure of the liquid storage container of the present invention.

FIG. 5 is a side view of a liquid storage container according to a second embodiment of the present invention as viewed from an end face facing an ink supply unit.

FIG. 6 is a side view of a liquid storage container according to a second embodiment of the present invention as viewed from an end face facing an ink supply unit.

FIG. 7 is a side view of an end face facing an ink supply unit in a second embodiment of the liquid container according to the present invention.

FIG. 8 is a schematic diagram of a recording head which is recording means connectable to the ink tank according to the first embodiment of the present invention.

FIG. 9 is a schematic view of an ink jet recording apparatus equipped with an ink tank according to the first embodiment of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 100 Ink tank 101 Outer wall 102 Inner wall 103 Ink supply unit 104, 104a Pinch-off unit 105 Air intake port 106 Ink lead-out permission member 107 Gap 108 Deformation promotion unit 109 Rib 110 Curved surface unit 201 Main accumulator 202 Main extruder 203 Secondary accumulator 204 Secondary extruder 205 Ring 206 Die 207 Parison 208 Die 209 Air nozzle 401 Recording head unit 402 Ink supply tube 403 Filter 404 Ink ejection unit

Claims (21)

[Claims] 1. An inner wall forming a liquid storage portion for storing a liquid therein, an outer wall having an inner surface having a shape equal to or similar to the outer surface of the inner wall and a substantial air communication portion, and A liquid container having a liquid supply unit for supplying a liquid, and a pinch-off unit in which a part where the inner wall is integrated with the outer wall is sandwiched by the outer wall, wherein a resin forming the inner wall and the outer wall is substantially A liquid storage container, wherein the inner wall has a surface portion which can be moved substantially in parallel while substantially maintaining the shape, and the pinch-off portion is present on the surface portion. 2. The liquid container according to claim 1, wherein the liquid container has a cylindrical shape, and the surface portion is located at one end surface of the cylinder. 3. The liquid container according to claim 1, further comprising a deformation accelerating portion having a smaller thickness than other portions around the surface of the inner wall. 4. The liquid container according to claim 1, wherein the liquid supply unit is provided on a surface facing the surface unit. 5. The liquid container according to claim 4, wherein a rib is provided on a surface portion of the inner wall. 6. The liquid container according to claim 4, wherein the liquid container has two or more pinch-off portions on a surface portion of the inner wall. 7. An inner wall forming a liquid storage portion for storing a liquid therein, an outer wall having an inner surface having a shape equal to or similar to the outer surface of the inner wall and a substantial air communication portion, and A liquid container having a liquid supply unit for supplying a liquid, and a pinch-off unit in which a part where the inner wall is integrated with the outer wall is sandwiched by the outer wall, wherein the inner wall has a pressure fluctuation in the inner wall due to the discharge of the liquid. A liquid container having a surface portion which moves while maintaining the shape substantially, and wherein the pinch-off portion is present on the surface portion. 8. The liquid container according to claim 7, wherein the liquid container has a cylindrical shape, and the surface portion is located at one end surface of the cylinder. 9. The liquid container according to claim 7, wherein a deformation promoting portion having a smaller thickness is provided around a surface of the inner wall. 10. The liquid container according to claim 7, wherein the liquid supply unit is provided on a surface facing the surface unit. 11. The liquid container according to claim 10, wherein a rib is provided on a surface portion of the inner wall. 12. The liquid container according to claim 10, wherein the inner wall has two or more pinch-off portions on a surface portion thereof. 13. An inner wall forming a liquid storage portion for storing a liquid therein, an outer wall having an inner surface having a shape equal to or similar to the outer surface of the inner wall and a substantially atmospheric communication portion, and A liquid container having a liquid supply unit for supplying a liquid, and a pinch-off portion in which a portion where the inner wall is integrated with the outer wall is sandwiched by the outer wall, wherein one of surfaces of the inner wall having a pinch-off portion is provided. A liquid container having a structure in which a force that buckles the other surface of the inner wall satisfies a relationship that requires a larger force than a force that deforms while maintaining the shape of the lip. 14. The liquid storage container has a cylindrical shape, one of the surfaces of the inner wall having a pinch-off portion is one end surface of the cylinder, and the other surface of the inner wall is a side surface of the cylinder. Item 14. The liquid container according to Item 13. 15. The liquid container according to claim 13, wherein a deformation promoting portion having a smaller thickness than the other is provided around one of the surfaces of the inner wall having the pinch-off portion. 16. The liquid container according to claim 13, wherein the liquid supply unit is provided on a surface of the inner wall facing one of surfaces having a pinch-off portion. 17. The liquid container according to claim 16, wherein one of the surfaces of the inner wall having the pinch-off portion has a rib. 18. The liquid container according to claim 16, wherein two or more pinch-off portions are provided on one of the surfaces of the inner wall having the pinch-off portion. 19. A liquid storage container according to claim 1, further comprising: a liquid ejection head joined to the liquid storage container to discharge a liquid. Head cartridge. 20. The head cartridge according to claim 19, wherein the liquid ejection head and the liquid storage container are relatively detachably configured. 21. A head cartridge comprising: the liquid storage container according to claim 1; and a liquid ejecting head that is connected to the liquid storage container and discharges a liquid according to a recording signal. A recording apparatus, comprising: a carriage on which the head cartridge is removably mounted and which is scanned.