JP2000006412A - Liquid jet head and recorder employing it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an easy-to-manufacture liquid jet head which can generate a high ejection force without deteriorating ejection efficiency by introducing the bubble generating pressure in a bubble generating region in the direction of ejection opening. SOLUTION: A substrate 110 arranged with heating elements 2, a thin film supporting member 131 having lower surface bonded with a movable separation film 5, and a grooved member 132 are laminated sequentially and tightly onto a support 136 and a orifice plate 9 is bonded tightly to the front face of the grooved member 132. Ejection liquid in a first liquid channel (ejection liquid channel) is separated completely from bubbling liquid in a second liquid channel (bubbling liquid channel) by the movable separation film 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a liquid discharge head for discharging a desired liquid by generating bubbles due to heat energy or the like, and a recording apparatus using the liquid discharge head.
In particular, the present invention relates to a liquid ejection head using a movable separation film that is displaced by utilizing the generation of bubbles.

In the present invention, "recording" means not only giving a meaningful image such as a character or a figure to a recording medium, but also printing a meaningless image such as a pattern. It also means giving.

[0003]

2. Description of the Related Art By giving energy such as heat to ink, a state change accompanied by a steep volume change (formation of air bubbles) is caused in the ink, and the ink is ejected from an ejection port by an action force based on this state change. An ink jet recording method in which an image is formed by attaching this to a recording medium, that is, a so-called bubble jet recording method, has been conventionally known.
A recording apparatus using this bubble jet recording method includes JP-B-61-59911 and JP-B-61-59914.
As disclosed in Japanese Patent Application Laid-Open Publication No. H10-157, an ejection port for ejecting ink, an ink flow path communicating with the ejection port, and an energy generating means for discharging ink arranged in the ink flow path. A heating element (electric heat conversion element) is generally provided.

According to the above-described recording method, a high-quality image can be recorded at high speed and with low noise, and in a head performing this recording method, ejection ports for ejecting ink are arranged at a high density. Therefore, it has many excellent points such that a high-resolution recorded image and a color image can be easily obtained with a small device. For this reason, this bubble jet recording method has recently been used in many office devices such as printers, copiers, and facsimile machines, and has been used in industrial systems such as textile printing devices.

On the other hand, in the conventional bubble jet recording method, heating is repeated while the heating element is in contact with the ink, so that deposits may be generated on the surface of the heating element due to scorching of the ink. In addition, in the case where the liquid to be discharged is a liquid which is easily deteriorated by heat or a liquid in which foaming is not sufficiently obtained, good discharge may not be performed by the above-described direct heating bubble formation by the heating element. .

[0006] On the other hand, the present applicant has disclosed in
Japanese Patent No. 81172 proposes a method in which a foaming liquid is foamed by thermal energy through a flexible membrane that separates the foaming liquid and the ejection liquid, and the ejection liquid is ejected. In this method, the structure of the flexible film and the foaming liquid is such that the flexible film is provided on a part of the nozzle, whereas a structure using a large film that vertically separates the entire head is used. It is disclosed in JP-A-59-26270. This large film is provided for the purpose of preventing the liquids in the two liquid paths from being mixed with each other by being sandwiched between two plate members forming the liquid paths.

On the other hand, the foaming liquid itself is characterized by taking into account the foaming characteristics, as disclosed in JP-A-5-229122, which uses a liquid having a boiling point lower than that of the discharge liquid. Japanese Patent Application Laid-Open No. 4-329148 uses a liquid having the same as a foaming liquid.

[0008]

However, the above-described conventional liquid discharge method using a separation membrane only has a structure in which a foaming liquid is separated from a discharge liquid, or only an improvement in the foaming liquid itself. It is not a practical level.

The inventors of the present invention have studied the droplet discharge using the separation film, focusing on the discharged droplets. Since the liquid discharge caused by the bubble formation due to the thermal energy involves the change of the separation film, Efficiency dropped, resulting in the conclusion that it was not put to practical use.

Therefore, the present inventors have studied a liquid discharge head capable of achieving a higher level of liquid discharge while utilizing the effect of the separation function of the separation membrane.

The present invention has been developed in the course of this research, and it is possible to improve the discharge efficiency for discharging liquid droplets, and to achieve an epoch-making method that stabilizes and increases the volume or the discharge speed of the discharged liquid droplets. It is intended to provide a liquid ejection head.

According to the present invention, there is provided a first liquid flow path for a discharge liquid communicating with a discharge port, a second liquid flow path provided to supply or move a foaming liquid and including a bubble generation region, and a first and a second liquid flow paths. A liquid having a displacement region of the movable separation film upstream of the discharge port with respect to the flow direction of the discharge liquid in the first liquid flow channel using a liquid discharge head having a movable separation film for separating the second liquid flow channel; In the ejection head, the ejection efficiency can be improved.

[0013] A first object of the present invention is to provide a structure in which a discharge liquid and a foaming liquid are substantially separated, more preferably completely separated, by a movable film. When transmitting the pressure to the discharge liquid by deforming, not only preventing the pressure from escaping to the upstream side, but also guiding the pressure toward the discharge port, it is possible to obtain a high discharge force without impairing the discharge efficiency An object of the present invention is to provide a liquid ejection head and a recording apparatus.

A second object of the present invention is to reduce the amount of deposits deposited on the heating element and efficiently discharge the liquid without thermally affecting the discharge liquid by the above-described structure. It is an object of the present invention to provide a liquid ejection head and a recording apparatus that can perform the above operation.

It is a third object of the present invention to provide a liquid discharge head and a recording apparatus having a wide selection degree regardless of the viscosity and material composition of a discharge liquid.

A fourth object of the present invention is to provide an inexpensive liquid ejecting head and a recording apparatus by adopting a structure capable of easily manufacturing a liquid ejecting head capable of obtaining the above-mentioned effects.

[0017]

To achieve the above object, a liquid discharge head according to the present invention comprises a first liquid flow path communicating with a discharge port for discharging a liquid, and a bubble generation region for generating a bubble in the liquid. A liquid separation head comprising: a second liquid flow path comprising: a first liquid flow path; and a movable separation film that always substantially separates the first liquid flow path and the second liquid flow path from each other. Is displaced on the upstream side of the discharge port with respect to the flow of the liquid in the first liquid flow path, and the downstream side of the movable separation membrane is relatively located on the downstream side of the movable separation membrane with respect to the flow direction of the liquid. A directional control means for largely displacing the discharge port side, and a thin film support member that supports the movable separation film by joining at least a part of the movable separation film.

In the liquid ejection head of the present invention having the above-described structure, at least a part of the movable separation film is joined to the thin film supporting member having a region capable of supporting the thin film on the surface. It has sufficient rigidity for handling and can prevent damage to the movable separation membrane. Therefore, handling of the movable separation membrane in the manufacturing process is easier than handling the movable separation membrane alone, and alignment can be performed accurately and easily.

Further, with the generation and growth of bubbles in the bubble generation region, the movable separation film provided on the bubble generation region is displaced toward the first liquid flow path. Since the downstream portion of the separation membrane is displaced to the first flow channel side more than the upstream portion of the movable separation membrane, the pressure due to the generation of bubbles is guided to the discharge side of the first liquid flow channel.

The direction control means is the movable separation membrane itself,
The movable separation membrane may have elasticity, or may be a movable member disposed adjacent to the movable separation membrane, or the movable member may be provided integrally with the thin film support member. Good.

Further, a heating element for generating heat for generating bubbles is provided at a position of the bubble generation region facing the movable separation film, and a direction control means is provided on the first liquid flow path side of the movable separation film. A movable separation membrane displacement regulating member that is provided with an opening formed to include a heating element in the vicinity of the bubble generation region, and that restricts displacement of the movable separation membrane. The thin film support member has an opening. It may be formed.

Further, the liquid supplied to the first liquid flow path and the liquid supplied to the second liquid flow path may be different liquids, and are supplied to the second liquid flow path. The liquid may be a liquid that is superior in at least one property among low viscosity, foaming property, and thermal stability as compared with the liquid supplied to the first liquid flow path.

Further, a liquid discharge apparatus according to the present invention includes the liquid discharge head according to the present invention, and recording medium transport means for transporting a recording medium receiving liquid discharged from the liquid discharge head. Alternatively, recording may be performed by discharging ink from a liquid discharge head and attaching the ink to a recording medium.

[0024]

Embodiments of the present invention will be described below with reference to the drawings. (First Embodiment) FIG. 1 is an exploded perspective view of a liquid discharge head according to a first embodiment of the present invention.

The liquid ejection head of the present embodiment has a support 1
36, the substrate 110 having the heating element 2 and the movable separation film 5
A thin film supporting member 131 and a grooved member 132 for supporting the groove are sequentially laminated in close contact with each other.

A substrate 110 is disposed on the upper surface of a support 136 formed of a metal such as aluminum. The substrate 110 is formed so as to communicate with the second liquid flow path 4 composed of a plurality of grooves formed by a dry film and to supply a foaming liquid to each of the second liquid flow paths 4. A second common liquid chamber (common foaming liquid chamber) 144 having a concave shape is formed. Further, each second liquid flow path (foaming liquid flow path) 4
Are provided with heating elements 2 which are electrothermal converters for generating bubbles of the foaming liquid by film boiling.

On the upper surface of the substrate 110, a thin film support member 131 is provided.
Are joined. The thin film support member 131 is
The opening 11 is formed, and the movable separation film 5 is joined to the lower surface. The movable separation film 5 has such a shape that the opening 11 is closed but the hole 10 is not closed. Since the movable separation film 5 is joined to the thin film support member 131, the movable separation film 5 has sufficient rigidity for handling and can prevent the movable separation film 5 from being damaged. However, it can be several steps easier than when the movable separation membrane 5 is used alone.

The grooved member 1 is provided on the upper surface of the thin film support member 131.
32 are joined. The grooved member 132 has a first
Liquid flow path (discharge liquid flow path) 3, first common liquid chamber (common discharge liquid chamber) 143, and first liquid supply path (discharge liquid supply path)
133 and a second liquid supply path (foaming liquid supply path) 134 are formed. Each first liquid flow path 3 which is a flow path of the discharge liquid is formed at a position corresponding to each second liquid flow path 4 formed on the substrate 110, and the first common liquid chamber 14
It communicates with 3. A first liquid supply path 133 for supplying a discharge liquid communicates with the upper part of the first common liquid chamber 143. Further, the second liquid supply path 134 penetrates from the upper surface to the lower surface of the grooved member 132, and the foaming liquid is discharged through the second liquid supply path 134 and the hole 10 of the thin film support member 131. The liquid is supplied to the second common liquid chamber 144 of the substrate 110 without being mixed.

The thin film support member 13 is provided on the lower surface of the grooved member 132.
After joining, the orifice plate 9 in which the discharge port 1 is formed at a position corresponding to the first liquid flow path 3 is joined to the front surface of the grooved member 132. Since the movable separation membrane 5 and the orifice plate 9 are fixed to each other,
The discharge liquids in the respective first liquid flow paths 3 do not mix.

As described above, since the movable separation film 5 is bonded to the thin film supporting member 131, handling such as bonding to the substrate can be easily performed. This facilitates the production of the liquid discharge head, and therefore can provide the liquid discharge head at low cost.

Further, since the first common liquid chamber 143 and the second common liquid chamber 144 are separated by the thin film supporting member 131 and the movable separation membrane 5, the first common liquid chamber 143 and the second common liquid chamber 144 are generated when only the movable separation membrane 5 is separated. The swing of the movable separation film 5 can be suppressed. This makes it possible to discharge the discharge liquid more stably.

Next, the operation of the liquid discharge head according to the present embodiment will be described with reference to the cross-sectional view in the flow direction shown in FIG.

In the present invention, the thin film support member 13
1 that focuses on the movement of the movable separation membrane 5 bonded to the lower surface of the movable separation membrane 1 and that includes means for regulating the direction of displacement acting directly or indirectly on the movable separation membrane 5 itself. Displacement (movement, expansion, extension, etc.) caused by bubbles in the film 5 was directed toward the discharge port.

In the initial state shown in FIG. 2A, the liquid in the first liquid flow path 3 is drawn to the vicinity of the discharge port 1 by capillary force. Note that, in the present embodiment, the discharge port 1 is positioned on the projection area of the heating element 2 onto the first liquid flow path 3.
The first liquid flow path 3 is located downstream with respect to the liquid flow direction.

In this state, when heat energy is applied to the heating element 2 (a heating resistor having a shape of 40 μm × 105 μm in this embodiment), the heating element 2 is rapidly heated, and the heating element 2 in the bubble generation area 7 is heated. The surface in contact with the second liquid heats and foams the second liquid (FIG. 2B). The bubbles 6 generated by this heating and foaming are described in US Pat.
These bubbles are based on the film boiling phenomenon described in No. 29, and are generated simultaneously with an extremely high pressure over the entire surface of the heating element. The pressure generated at this time is
As a pressure wave, the second liquid in the second liquid flow path 4 propagates and acts on the movable separation membrane 5, whereby the movable separation membrane 5 is displaced and the first liquid flow path 3 The discharge of the second liquid in the inside is started.

When the bubbles 6 generated on the entire surface of the heating element 2 grow rapidly, they become a film (FIG. 2C). The expansion of the bubble 6 due to the extremely high pressure in the initial stage of the generation causes the movable separation membrane 5 to be further displaced, whereby the discharge of the first liquid in the first liquid flow path 3 from the discharge port 1 proceeds.

Thereafter, as the bubbles 6 further grow, the displacement of the movable separation film 5 increases (FIG. 2D). Until the state shown in FIG. 2D, the movable separation membrane 5 is displaced by the upstream side 5A and the downstream side 5B with respect to the central part 5C of the region of the movable separation membrane 5 facing the heating element 2. Is continued to be substantially equal to the displacement.

Thereafter, when the bubble 6 further grows, the bubble 6 and the movable separation membrane 5 which continues to be displaced are relatively displaced toward the discharge port at the downstream side 5B relatively more than the upstream side 5A. The first liquid in the first liquid flow path 3 is directly moved in the direction of the discharge port 1 (FIG. 2).
(E)).

As described above, the step of displacing the movable separation film 5 in the discharge direction on the downstream side so as to directly move the liquid toward the discharge port improves the discharge efficiency.
Further, the movement of the liquid relatively upstream is reduced,
This effectively acts on the refilling (replenishment from the upstream side) of the liquid in the nozzle, particularly in the displacement area of the movable separation membrane 5.

As shown in FIGS. 2 (d) and 2 (e), the movable separation film 5 itself is displaced in the direction of the discharge port so as to change from FIG. 2 (d) to FIG. 2 (e). The discharge efficiency and the refill efficiency described above can be further improved, and the first liquid in the projection area of the heating element 2 in the first liquid flow path 3 is transported and moved in the direction of the discharge port, so that the discharge amount is increased. Can be improved.

Further, according to the configuration of the present embodiment, the discharge liquid can be discharged by using the discharge liquid and the foaming liquid as different liquids. For this reason, even if a high-viscosity liquid such as polyethylene glycol, which has conventionally been insufficiently foamed even when heat is applied and discharge power is insufficient, this liquid is supplied to the first liquid flow path 3. A liquid in which foaming is performed well in a foaming liquid (ethanol: water = 4: 6 mixed solution, about 1 to 2 cp, etc.)
Can be satisfactorily discharged by supplying the liquid to the second liquid flow path 4.

Also, by selecting a liquid that does not generate deposits such as kogation on the surface of the heating element even when it receives heat, foaming can be stabilized and good ejection can be performed.

Further, in the structure of the liquid discharge head according to the present invention, since the effects described in the above-described embodiments are also produced, it is possible to discharge a liquid such as a highly viscous liquid with a higher discharge efficiency and a higher discharge force. it can.

Even when a liquid weak to heating is used, this liquid is supplied to the first liquid flow path 3 as a discharge liquid, and the second liquid flow path 4 is hardly thermally deteriorated and foams well. Is supplied without causing thermal harm to liquids that are weak to heating, and can be discharged with high discharge efficiency and high discharge force as described above.

Next, a process of manufacturing the movable separation film 5 of the liquid ejection head of the present embodiment will be described with reference to FIGS.

First, as shown in FIG. 3A, a release agent 40 is applied on a silicon wafer 41. Then, FIG.
As shown in (b), a liquid polyimide resin 42 to be the movable separation film 5 is spin-coated to form a film. Next, as shown in FIG. 3C, a thin film support member 131 made of a metal such as nickel 43 is bonded on the polyimide resin 42,
Cut the four sides of the outer circumference with a cutter. Thereafter, as shown in FIG. 3D, the movable separation film 5 made of the polyimide resin 42 joined to the nickel 43 as the thin film support member 131 was peeled off from the silicon wafer 41 to produce. (Second Embodiment) FIG. 4 is an exploded perspective view of a liquid discharge head according to a second embodiment of the present invention.

The configuration of the liquid ejection head of this embodiment shown in FIG. 4 is the same as that of the first embodiment except that the shape of the thin film support member 231 is different.
Description will be made using the same reference numerals as in the first embodiment, except for the reference numerals related to the thin film support member 231. The method of manufacturing the movable separation film 5 is the same as that of the first embodiment.

The thin-film support member 231 of this embodiment has a plurality of movable members 151 formed as direction control members. Each movable member 151 is disposed so as to correspond to each of the first liquid flow path 3 and the second liquid flow path 4.

In this embodiment, since the movable member 151 is provided on the thin film supporting member 231 joined to the movable separation membrane 5, the handling of the movable separation membrane 5 in the manufacturing process becomes easy, and the first liquid flow path 3 Also, alignment with the second liquid flow path 4 can be performed accurately and easily. Therefore, the liquid discharge head can be easily manufactured, and therefore, the liquid discharge head can be provided at low cost, and the discharge efficiency can be improved.

Further, since the first common liquid chamber 143 and the second common liquid chamber 144 are separated by the thin film support member 231 and the movable separation film 5, the movable liquid that occurs when separated by only the movable separation film 5 is movable. The swing of the separation membrane 5 can be suppressed. Thereby, ejection can be performed more stably.

FIG. 5 is a sectional view of a liquid discharge head according to a second embodiment of the present invention in the flow direction. Next, the operation of the liquid discharge head of the present embodiment will be described in the flow direction shown in FIG. This will be described with reference to the sectional view of FIG.

As shown in FIG. 5A, in the present embodiment, the heating element 2 (40 μm × 105 in the present embodiment) for applying heat energy to generate bubbles in the liquid.
A second liquid flow path 4 for a foaming liquid is provided on a substrate 110 provided with a heating resistor having a shape of μm), and a first liquid for a discharge liquid directly communicated with a discharge port 1 thereon. A channel 3 is provided. In addition, a movable separation membrane 5 formed of an elastic thin film is provided between the first liquid flow path 3 and the second liquid flow path 4. Road 3
And the foaming liquid in the second liquid flow path 4 are separated. The movable separation film 5 is disposed so as to face the heating element 2 and faces at least a part of a bubble generation region 7 in which bubbles are generated by heat generation in the heating element 2.
Further, on the first liquid flow path 3 side of the movable separation film 5, the movable separation film 5 has a free end 151 a on the bubble generation region 7 and a fulcrum 151 b on the upstream side of the free end 151 a, respectively. A movable member 151 is provided as a direction restricting means arranged. The movable member 151 is a thin film support member 131.
It is provided above.

The free end 151a of the movable member 151 is provided on the downstream side with respect to the fulcrum 151b even if it is not provided on the portion facing the bubble generation region 7, and discharges the movable separation film 5 to extend. It is only necessary to guide the heating element 2 in the direction of the outlet 1. More preferably, the displacement of the movable separation membrane 5 can be efficiently controlled by facing at least a part of the heating element 2 via the movable separation membrane 5. . In particular, the heating element 2
Alternatively, the movable member 151 is positioned downstream of the area center of the bubble generation region 7 so as to face the movable separation membrane 5 such that the free end 151a thereof is located.
Since it becomes possible to concentrate the component which is about to expand in the direction perpendicular to the heating element 2 in the direction of the discharge port 1, the discharge efficiency is dramatically improved. Further, even when the free end 151a is provided on the downstream side of the bubble generation region 7, the free end 151a is further displaced to displace the movable separation film 5 more in the direction of the discharge port 1, so that the discharge is performed. Efficiency is improved.

When heat is generated in the heating element 2, bubbles 6 are generated in a bubble generation area 7 on the heating element 2, whereby the movable separation film 5 is displaced toward the first liquid flow path 3. However, here, in the movable separation membrane 5, the movable member 151
Regulates its displacement. In the movable member 151, since the free end 151a is provided on the bubble generation region 7 and the fulcrum 151b is provided upstream thereof, the movable separation membrane 5 is displaced more greatly on the downstream side than on the upstream side. (FIG. 5 (b)).

That is, the desired deformation and displacement can be stably obtained by the direction regulating means for regulating the direction in which the movable separation film 5 is displaced.

Thus, as the bubble 6 grows,
The downstream portion of the movable separation membrane 5 is greatly displaced, whereby the growth of the bubbles 6 is mainly transmitted to the discharge port 1 side, and the discharge liquid in the first liquid flow path 3 is efficiently discharged from the discharge port 1. Discharged.

Thereafter, when the bubble 6 contracts, the movable separation membrane 5
Returns to the position before the displacement, but at that time, the movable separation membrane 5 is displaced toward the second liquid flow path 4 from the position before the displacement due to the pressure of the defoaming. However, in the present embodiment, since the movable separation membrane 5 is integrated with the movable member 151, the displacement of the movable separation membrane 5 toward the second liquid flow path 4 is suppressed (FIG. 5C). ).

Therefore, a decrease in the pressure on the first liquid flow path 3 side is suppressed, whereby the retraction of the meniscus is suppressed, and the refill characteristics are improved.

Further, the movement of the liquid to the upstream side is suppressed by the movable member 151, and effects such as improvement of refill characteristics and reduction of crosstalk can be obtained.

Further, according to the structure of the present embodiment, the discharge liquid and the foaming liquid can be made different liquids, and the discharge liquid can be discharged. For this reason, even if a high-viscosity liquid such as polyethylene glycol, which has conventionally been insufficiently foamed even when heat is applied and discharge power is insufficient, this liquid is supplied to the first liquid flow path 3. A liquid in which foaming is performed well in a foaming liquid (ethanol: water = 4: 6 mixed solution, about 1 to 2 cp, etc.)
Can be satisfactorily discharged by supplying the liquid to the second liquid flow path 4.

Further, by selecting a liquid that does not generate deposits such as kogation on the surface of the heating element even when it receives heat, foaming can be stabilized and good discharge can be performed.

Further, in the structure of the liquid discharge apparatus of the present invention, the effect as described in the above-described embodiment is also obtained, so that it is possible to discharge a liquid such as a highly viscous liquid with a higher discharge efficiency and a higher discharge force. it can.

Even when a liquid weak to heating is used, this liquid is supplied to the first liquid flow path 3 as a discharge liquid, and the second liquid flow path 4 is hardly thermally degraded and foams well. Is supplied without causing thermal harm to liquids that are weak to heating, and can be discharged with high discharge efficiency and high discharge force as described above. (Third Embodiment) FIG. 6 is an exploded perspective view of a liquid discharge head according to a third embodiment of the present invention.

The configuration of the liquid discharge head of this embodiment shown in FIG. 6 is the same as that of the first embodiment except that the shape of the thin film support member 331 is different.
Description will be made using the same reference numerals as in the first embodiment, except for the reference numerals related to the thin film support member 331. The method of manufacturing the movable separation film 5 is the same as that of the first embodiment.

In the thin film support member 331 of this embodiment, the plurality of openings 31 for regulating the displacement of the movable separation membrane 5 as the direction control members correspond to the first liquid flow path 3 and the second liquid flow path 4. It is formed at the position where it does.

With the above-described configuration, the handling of the movable separation membrane 5 in the manufacturing process becomes easy, and the alignment with the first liquid flow path and the second liquid flow path can be performed accurately and easily. Therefore, the liquid discharge head can be easily manufactured, and therefore, the liquid discharge head can be provided at low cost, and the discharge efficiency can be improved.

Further, since the first common liquid chamber 143 and the second common liquid chamber 144 are separated by the thin film supporting member 331 and the movable separation film 5, the movable liquid that occurs when separated by the movable separation film 5 alone is movable. The swing of the separation membrane 5 can be suppressed. Thereby, ejection can be performed more stably.

Next, the operation of the liquid ejection head according to the present embodiment will be described with reference to the cross-sectional view in the flow direction shown in FIG.

In the present embodiment, as in the previous embodiments, the heating element 2 (in this embodiment, 40 μm × 10
A second liquid flow path 4 for a foaming liquid is provided on a substrate 110 on which a heating resistor having a shape of 5 μm is provided, and a first liquid for a discharge liquid directly communicated with a discharge port 1 thereon. A channel 3 is provided. In addition, a movable separation membrane 5 formed of an elastic thin film is provided between the first liquid flow path 3 and the second liquid flow path 4. Road 3
And the foaming liquid in the second liquid flow path 4 are separated. Further, a feature of the present embodiment is that the opening 31 is formed in the vicinity of the movable separation membrane 5 on the first liquid flow path 3 side, thereby restricting the displacement of the movable separation membrane 5. . The opening 31 is formed in the thin film support member 331.

Hereinafter, the discharge operation of the liquid discharge head of this embodiment will be described in detail with reference to FIG.

In FIG. 7A, no energy such as electric energy is applied to the heating element 2, and no heat is generated in the heating element 2. The movable separation film 5 is at a first position substantially parallel to the substrate 110.

What is important here is that the center of the opening 31 that regulates the displacement of the movable separation membrane 5 is provided on the downstream side of the center of the heating element 2. The center of the movable region is located downstream of the center of the heating element 2.

Here, when electric energy or the like is applied to the heating element 2, a part of the foaming liquid filling the bubble generation region 7 is heated by the heat generated by the heating element 2, and the heat is generated by the film boiling. Bubbles 6 are generated. Since the center of the movable region of the movable separation membrane 5 is located downstream of the center of the heating element 2, the movable separation membrane 5 is easily displaced downstream of the heating element 2 by the pressure of the bubbles 6. (FIG. 7
(B)).

When the bubble 6 further grows, the movable separation membrane 5 is further displaced toward the first liquid flow path 3 in accordance with the pressure generated by the bubble generation. As a result, the generated bubble 6 grows greatly from the upstream to the downstream, and the movable separation membrane 5 greatly exceeds the first position (FIG. 7C).

Thereafter, when the bubble 6 contracts due to a decrease in the bubble internal pressure characteristic of the film boiling phenomenon described above,
Accordingly, the movable separation membrane 5 that has been displaced to the second position is moved by the negative pressure due to the contraction of the bubble 6 as shown in FIG.
7 (d) gradually returns to the initial position (first position) shown in FIG.

When the bubbles 6 disappear, the movable separation film 5 returns to the initial position (first position) (FIG. 7E).
Further, at the time of defoaming, in order to compensate for the volume of the ejected liquid, as shown from the upstream side, that is the common liquid chamber side to the V _D1, V _D2, also the liquid as shown in V _C from the discharge port 1 side Comes in. At this time, since the liquid flowed from the heating element 2 to the downstream side (discharge port 1 side) during foaming, V _D1 , V _D
The flow of _D2 is increased, which greatly contributes to improving the refill speed and attenuating the retreat amount of the meniscus.

Here, as shown in FIG. 7, the opening 31 for regulating the displacement of the movable separation film 5 has a curved shape in the thickness direction, so that the stress of the movable separation film 5 at this portion is reduced. Concentration is eased, strength is less deteriorated, and durability is improved.

As described above, according to the configuration of the present embodiment, the center of the movable area of the movable separation membrane is located downstream of the center of the heating element, so that the movable area is displaced in accordance with the pressure caused by the bubble generation. Since the movable separation film grows on the downstream side, it is possible to efficiently discharge a liquid weak to heating or a highly viscous liquid at a high discharge pressure. Further, the discharge amount is further increased by the transporting action of the liquid in the first liquid flow path. (Other Embodiments) FIG. 8 is a schematic perspective view showing an example of an ink jet recording apparatus which is a liquid discharge apparatus to which the above-described liquid discharge head is mounted and which can be applied. In FIG. 8, reference numeral 601 denotes an ink jet head cartridge in which the above-described liquid ejection head and ink tank are integrated or the ink tank is detachable. The head cartridge 601 has a spiral groove 606 of a lead screw 605 that rotates via driving force transmission gears 603 and 604 in conjunction with forward and reverse rotation of a driving motor 602.
The carriage 6 is mounted on a carriage 607 that engages with the carriage 6.
07 is reciprocated along the guide 608 in the directions of arrows a and b. A paper pressing plate 610 for a print sheet (recording material) P conveyed on a platen 609 by a recording medium supply device (not shown) presses the print sheet P against a platen roller 609 in the carriage movement direction.

In the vicinity of one end of the lead screw 605, photocouplers 611 and 612 are provided. These are home position detecting means for confirming the presence of the lever 607a of the carriage 607 in this area and switching the rotation direction of the drive motor 602 and the like.
In the figure, reference numeral 613 denotes a support member that supports a cap member 614 that covers the front surface of the above-described liquid discharge head having the discharge ports. Reference numeral 615 denotes an ink suction unit that sucks ink accumulated by the head 601, such as idle discharge, inside the cap member 614. The suction unit 615 performs suction recovery of the head 601 via the opening in the cap. Reference numeral 617 denotes a cleaning blade, and reference numeral 618 denotes a moving member that enables the blade 617 to move in the front-rear direction (a direction orthogonal to the moving direction of the carriage 607). The blade 617 and the moving member 618 are body support members. 619. The blade 617 is not limited to this form,
Other well-known cleaning blades may be used. Reference numeral 620 denotes a lever for starting suction in the suction recovery operation, and the cam 62 engaged with the carriage 607.
1 and the driving force from the driving motor 602 is controlled by a known transmission means such as clutch switching. An ink jet recording control unit for giving a signal to the heating element 202 provided on the head 601 and controlling the driving of each mechanism described above is provided on the apparatus main body side, and is not shown here.

In the ink jet recording apparatus 600 having the above-described configuration, the recording is performed while the head 601 reciprocates over the entire width of the paper P conveyed on the platen 609 by the recording material supply device (not shown). .

[0081]

As described above, according to the present invention, since at least a part of the movable separation film of the liquid discharge head is joined to the thin film support member having a region capable of supporting the thin film on the surface, the movable head is movable. The separation membrane has sufficient rigidity for handling and can prevent damage to the movable separation membrane. Therefore, in the manufacturing process, handling is easier than handling the movable separation membrane alone, and alignment can be performed accurately and easily.

Further, with the generation and growth of bubbles in the bubble generation region, the movable separation film provided on the bubble generation region is displaced toward the first liquid flow path. Since the downstream portion of the separation membrane is displaced to the first flow channel side more than the upstream portion of the movable separation membrane, the pressure due to the generation of bubbles is guided to the discharge side of the first liquid flow channel. Thereby, the liquid in the first liquid flow path is efficiently discharged from the discharge port due to generation of bubbles.

As described above, an inexpensive liquid discharge head and a recording apparatus using the liquid discharge head can be provided, and the discharge efficiency can be improved.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view illustrating a liquid ejection head according to a first embodiment.

FIG. 2 is a sectional view in the flow channel direction for explaining the operation of the liquid ejection head shown in FIG.

FIG. 3 is a diagram illustrating a step of manufacturing a movable separation film of the present invention.

FIG. 4 is an exploded perspective view illustrating a liquid ejection head according to a second embodiment.

FIG. 5 is a cross-sectional view in the flow channel direction for explaining the operation of the liquid ejection head shown in FIG.

FIG. 6 is an exploded perspective view illustrating a liquid ejection head according to a third embodiment.

FIG. 7 is a cross-sectional view in the flow channel direction for explaining the operation of the liquid ejection head shown in FIG.

FIG. 8 is a schematic perspective view showing an example of an ink jet recording apparatus which is a liquid ejection apparatus to which the liquid ejection head of the present invention can be mounted and applied.

[Explanation of symbols]

 Reference Signs List 1 discharge port 2 heating element 3 first liquid flow path (discharge liquid flow path) 4 second liquid flow path (foaming liquid flow path) 5 movable separation membrane 6 bubble 7 bubble generation area 9 orifice plate 10 hole 11, 21, 31 Opening 40 Release agent 41 Silicon wafer 42 Polyimide resin 43 Nickel 110 Substrate 131, 231, 331 Thin film support member 132 Grooved member 133 First liquid supply path (foaming liquid supply path) 134 Second liquid supply Path (discharge liquid supply path) 136 Support 143 First common liquid chamber (common discharge liquid chamber) 144 Second common liquid chamber (common foaming liquid chamber) 151 Movable member 151a Free end 151b Support point 600 Inkjet recording device 601 Inkjet Head cartridge 602 Driving motor 603, 604 Driving force transmission gear 605 Lead screw 606 Spiral groove 607 Cap Tsu di 607a lever 608 guide 609 platen 610 paper pressing plate 611, 612 photocoupler 613 supporting member 614 cap member 615 ink suction means 617 cleaning blade 618 moves member 619 main support 620 lever 621 cams P print paper

Continuation of the front page (72) Fumi Yoshihira, Inventor 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Satoshi Shimazu 3-30-2, Shimomaruko, Ota-ku, Tokyo Canon Inc. F-term (reference) 2C057 AF52 AF93 AG12 AG46 AG58 AH03 BA05 BA13

Claims (9)

[Claims] A first liquid flow path that communicates with a discharge port that discharges a liquid; a second liquid flow path that includes a bubble generation region that generates bubbles in the liquid; and the first liquid flow path. A liquid separation head having a movable separation film that always substantially separates the second liquid flow path from each other, wherein the movable separation film is located at a position higher than the discharge port with respect to the flow of the liquid in the first liquid flow path. Direction control means for displacing on the upstream side, and displacing the downstream side of the movable separation membrane with respect to the liquid flow direction relatively more toward the discharge port side than the upstream side of the movable separation membrane, at least one of the movable separation membranes And a thin film support member partially joined to support the movable separation film. 2. The liquid discharge head according to claim 1, wherein the direction control means is the movable separation film itself, and the movable separation film has elasticity. 3. The liquid discharge head according to claim 1, wherein the direction control means is a movable member arranged adjacent to the movable separation film. 4. The liquid discharge head according to claim 3, wherein the movable member is provided integrally with the thin film support member. 5. The liquid discharge head according to claim 1, wherein a position of the bubble generation region facing the movable separation film is:
A heating element that generates heat for generating the bubbles, wherein the direction control unit includes the heating element near the bubble generation region on the first liquid flow path side of the movable separation membrane. A movable separation membrane displacement restricting member that is provided with the formed opening and restricts the displacement of the movable separation membrane, wherein the thin film support member has the opening formed therein. Liquid ejection head. 6. The liquid ejection head according to claim 1, wherein a liquid supplied to the first liquid flow path and a liquid supplied to the second liquid flow path are provided. Are liquids different from each other. 7. The liquid ejection head according to claim 6, wherein the liquid supplied to the second liquid flow path has a lower viscosity than the liquid supplied to the first liquid flow path. Foaming,
A liquid ejection head characterized in that the liquid is excellent in at least one property among thermal stability. 8. A liquid comprising: the liquid discharge head according to claim 1; and a recording medium transport unit that transports a recording medium that receives the liquid discharged from the liquid discharge head. Discharge device. 9. The liquid ejecting apparatus according to claim 8, wherein recording is performed by ejecting ink from the liquid ejecting head and attaching the ink to a recording medium.