JPH1071719A - Liquid discharging head and liquid discharging apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To transmit the growth of a generated bubble further intensively efficiently to an upper side or to a discharge opening side by a method wherein a bubble is more largely expanded to a downstream than an upperstream in a direction toward the discharge opening by displacement of a movable component to discharge liquid, and a bubble forming area is so formed as to satisfy a specific relation. SOLUTION: A heating element 2 is heated, and a bubble based on a film boiling phenomenon is generated in liquid 11 of a bubble generation area 11. Propagation of pressure based on generation of the bubble and growth of the bubble itself are transmitted to the discharge opening 18 side by displacing a movable component 31 on which the pressure and the bubble based on generation of the bubble are acted, so as to be largely opened to the discharge opening 13 side by taking a fulcram 33 as a center. In this case, the expansion area related to the foam 2 of the bubble is formed to satisfy the relation, (width of expansion effective area)<=(width of bubble generation area)<=(width of heating element). The relation is preferably (width of heating element)-8μm<=(width of bubble generation area), and further, (area of expansion effective area)<=(area of movable component). Under a standstill state, the movable component 31 is constituted so as to seal the expansion effective area hermetically.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid discharge head for discharging a desired liquid by a novel discharge principle,
In particular, the present invention relates to a liquid ejection head and a liquid ejection apparatus having a structure in which a movable member is displaced by utilizing generation of bubbles.

[0002] Further, the liquid discharge head of the present invention comprises paper,
Thread, fiber, cloth, leather, metal, plastic, glass,
Applied to printers, copiers, facsimile machines with communication systems, word processors with printer units, etc. that record on recording media such as wood and ceramics, as well as industrial recording devices combined with various processing devices. This is a possible invention.

In the present invention, "recording" means not only giving an image having a meaning such as a character or a figure to a recording medium, but also giving an image having no meaning such as a pattern. Is also meant.

[0004]

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 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 the ink onto a recording medium, that is, a so-called bubble jet recording method, is conventionally known. As disclosed in U.S. Pat. No. 4,723,129, a recording apparatus using this bubble jet recording method includes a discharge port for discharging ink, and an ink flow path communicating with the discharge port. Generally, an electrothermal converter as an energy generating means for discharging ink arranged in the ink flow path is generally arranged.

According to such a 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 advantages 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.

[0006] As the bubble jet technology is used for products in various fields, the following various requirements have been increasing in recent years.

[0007] For example, as a study on a demand for improvement in energy efficiency, optimization of a heating element such as adjusting the thickness of a protective film is mentioned. This method is effective in improving the propagation efficiency of generated heat to the liquid.

In addition, in order to obtain a high quality image, a driving condition for providing a liquid discharging method or the like in which the ink discharging speed is high and a good ink discharging can be performed based on stable bubble generation has been proposed. From the viewpoint of high-speed printing, there has also been proposed a print head having an improved flow path shape in order to obtain a liquid discharge head having a high filling (refilling) speed of the discharged liquid into the liquid flow path.

[0009] Of the flow path shapes, FIG.
(A) and (b) are disclosed in JP-A-63-199997.
No. 2, for example. The flow path structure and the head manufacturing method described in this publication are based on the back wave (pressure in the direction opposite to the direction toward the discharge port, that is, the pressure in the liquid chamber 12) generated by the generation of bubbles. It is an invention which pays attention to. This back wave is known as loss energy because it is not energy directed toward the ejection direction.

The invention shown in FIGS. 22 (a) and 22 (b) shows a valve 1 which is located farther from the bubble generation region formed by the heating element 2 and located on the opposite side of the discharge port 11 with respect to the heating element 2.
0 is disclosed.

In FIG. 22B, this valve 10 is
It is disclosed that it has an initial position as attached to the ceiling of the flow channel 3 and hangs down into the flow channel 3 with the generation of bubbles by a manufacturing method using a plate material or the like. The present invention is disclosed as controlling the energy loss by controlling a part of the back wave by the valve 10.

However, in this configuration, as will be understood from consideration of the case where air bubbles are generated inside the flow path 3 for holding the liquid to be discharged, suppression of a part of the back wave by the valve 10 is not possible with liquid discharge. Is not practical.

Originally, the back wave itself is not directly related to the ejection as described above. At the time when this back wave is generated in the flow path 3, as shown in FIG.
The pressure of the bubbles that is directly related to the discharge has already made the liquid dischargeable from the flow path 3. Therefore, it is clear that even if only a part of the back wave is suppressed, the ejection is not greatly affected.

On the other hand, in the bubble jet recording method, since heating is repeated while the heating element is in contact with the ink, deposits are generated on the surface of the heating element due to scorching of the ink. In some cases, the generation of bubbles causes the generation of bubbles to be unstable, making it difficult to discharge ink satisfactorily. Further, even 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 difficult to be sufficiently obtained, a method for discharging the liquid to be discharged without changing the quality is desired. .

[0015] From such a viewpoint, the liquid (foaming liquid) that generates bubbles by heat and the liquid (ejected liquid) to be ejected are separated liquids, and the ejected liquid is ejected by transmitting the pressure due to foaming to the ejected liquid. The method is described in JP-A-61-69467, JP-A-55-81172, US Pat.
No. 0,259, and the like. In these publications, the ink, which is the ejection liquid, and the foaming liquid are completely separated by a flexible film such as silicon rubber so that the ejection liquid does not come into direct contact with the heating element, and the pressure due to the foaming of the foaming liquid is controlled. The configuration is such that the liquid is transmitted to the discharge liquid by deformation of the flexible film.
Such a configuration achieves prevention of deposits on the surface of the heating element, improvement in the degree of freedom in selecting the liquid to be discharged, and the like.

However, as described above, in the head having a structure in which the discharge liquid and the foaming liquid are completely separated, the pressure at the time of foaming is transmitted to the discharge liquid by expansion and contraction deformation of the flexible film. Is considerably absorbed by the flexible membrane. Further, since the amount of deformation of the flexible film is not so large, the effect of separating the ejection liquid and the foaming liquid can be obtained, but there is a possibility that the energy efficiency and the ejection force are reduced.

[0017]

SUMMARY OF THE INVENTION The present invention is based on the fundamental discharge characteristics of a conventional system in which a bubble (particularly a bubble accompanying film boiling) is formed in a liquid flow path to discharge a liquid. The main task is to raise the level to a level that cannot be predicted in the past, from a viewpoint that could not be considered in the past.

Some of the inventors went back to the principle of droplet discharge and conducted intensive research to provide a novel droplet discharge method utilizing bubbles which could not be obtained conventionally, and a head and the like used therefor. . At this time, the first technology analysis starting from the operation of the movable member in the liquid flow path, which is to analyze the principle of the mechanism of the movable member in the flow path, and the second technology starting from the principle of discharging droplets by bubbles The analysis, and further, the third analysis starting from the bubble formation region of the heating element for forming bubbles is performed.

According to these analyses, the positional relationship between the fulcrum and the free end of the movable member is determined to be such that the free end is located on the discharge port side, that is, on the downstream side, and the movable member faces the heating element or the bubble generation region. This has led to the establishment of a completely new technology for actively controlling air bubbles.

Next, it has been found that considering the energy that the bubble itself gives to the ejection amount, consideration of the growth component on the downstream side of the bubble is the largest factor that can significantly improve the ejection characteristics. That is, it has been found that the efficient conversion of the growth component on the downstream side of the bubble in the ejection direction leads to the improvement of the ejection efficiency and the ejection speed. From this,
The inventors have reached a very high technical level as compared with the conventional state of the art in which the growth component on the downstream side of the bubble is positively moved to the free end side of the movable member.

Further, a heating area for forming bubbles,
For example, a structural element such as a movable member or a liquid flow path that is involved in the growth of the downstream side of the bubble, such as the area center on the surface that controls foaming, downstream from the center line passing through the area center in the liquid flow direction of the electrothermal converter. It has been found that it is also preferable to take into account the above.

On the other hand, it has been found that the refill speed can be greatly improved by considering the arrangement of the movable member and the structure of the liquid supply path.

Some of the present inventors and the applicant have applied for the knowledge obtained through such research and the principle of excellent liquid ejection from a comprehensive point of view. This led to recalling a more favorable idea.

The present inventors have recognized that the present invention particularly provides a high-density liquid discharge head while further stabilizing the discharge force by considering the arrangement relationship between the heating element and the second liquid path. That is to do.

The main objects of the present invention are as follows. The first object is to direct the growth of the generated bubbles more efficiently and efficiently to the upper side or the discharge port side depending on the arrangement relationship between the bubble generation region and the heating element. It is an object of the present invention to provide a liquid discharge head and a liquid discharge device which can transmit and transmit information.

The second object of the present invention is to improve the discharge efficiency and the discharge pressure, to greatly reduce the heat storage in the liquid on the heating element, and to reduce the residual bubbles on the heating element. Another object of the present invention is to provide a liquid discharge head and a liquid discharge device capable of discharging a good liquid.

A third object of the present invention is to reduce the amount of meniscus retreat by suppressing the inertial force acting in the direction opposite to the liquid supply direction due to the back wave and at the same time by using the valve function of the movable member. It is an object of the present invention to provide a liquid discharge head and a liquid discharge apparatus in which a refill frequency is increased and a printing speed and the like are improved.

A fourth object of the present invention is to provide a liquid discharge head and a liquid discharge head which can reduce deposits on a heating element and can widen a range of use of a discharge liquid, and have sufficiently high discharge efficiency and discharge force. It is to provide a liquid ejection device.

A fifth object of the present invention is to provide a liquid discharge head and a liquid discharge apparatus which can increase the degree of freedom in selecting a liquid to be discharged.

A sixth object of the present invention is to provide a liquid discharge head and a liquid discharge apparatus which can easily manufacture the above-described liquid discharge head.

[0031]

In order to achieve the above object, the present invention provides a discharge port for discharging a liquid, a bubble generation region for generating bubbles by applying heat to the liquid with a heating element, and A movable member disposed to face the bubble generation region and capable of being displaced between a first position and a second position farther from the bubble generation region than the first position; ,
By the pressure based on the generation of bubbles in the bubble generator,
Displaced from the first position to the second position,
A liquid ejection head that ejects liquid by greatly expanding the bubble downstream from an upstream in a direction toward an ejection port by displacement of the movable member, wherein a heating element includes a foaming region that is involved in foaming. The liquid discharge is characterized in that the width centers of the heating element and the effective foaming area in the flow direction of the liquid are equal, and the condition of the bubble generation area is: effective foaming area ≦ width of bubble generation area ≦ heating element width. In the head.

Further, the present invention is characterized in that in the above-described liquid discharge head, the width of the heating element−8 μm ≦ the width of the bubble generation region.

Further, according to the present invention, in the above-described liquid discharge head, when the flow direction of the liquid is the length direction of the heating element and the effective foaming area, the condition of the bubble generating area is: length of the effective foaming area ≦ bubble generating area. Length ≦ the length of the heating element.

Further, according to the present invention, in the above liquid discharge head, the area of the effective bubbling area ≦ the area of the movable member,
In a stationary state, the movable member seals the effective foaming area.

In the present invention, (width of effective foaming area ≦
By setting (the width of the bubble generation area ≦ the width of the heating element), the generated bubbles can be grown upward or toward the discharge port. Thereby, the ejection force can be made more stable. Further, the density can be increased, and the image quality can be improved.

In addition, according to the liquid ejection method, the head and the like of the present invention based on the extremely novel ejection principle as described above, it is possible to obtain a synergistic effect between the generated bubble and the movable member displaced by the bubble. Since the liquid in the vicinity of the discharge port can be efficiently discharged, the discharge efficiency can be improved as compared with the conventional bubble jet method, head, and the like. For example, in the most preferred embodiment of the present invention, a dramatic improvement in the discharge efficiency of twice or more could be achieved.

According to a further characteristic configuration of the present invention,
Even if it is left for a long time at low temperature or low humidity, it is possible to prevent non-discharging, and even if it becomes non-discharging, it is possible to immediately return to a normal state by performing a slight recovery process such as preliminary discharge and suction recovery There is also an advantage that you can return.

More specifically, even under a long-term storage condition in which most of the conventional bubble jet type heads having 64 discharge ports do not discharge, about half or less discharge ports of the head of the present invention have defective discharge. It just becomes. In addition, when these heads are recovered by preliminary ejection, it is necessary to perform thousands of preliminary ejections with the conventional head for each ejection port,
In the present invention, it was sufficient to perform the recovery with about 100 preliminary ejections. This means that the recovery time can be shortened, the loss of liquid due to recovery can be reduced, and the running cost can be significantly reduced.

In particular, according to the configuration of the present invention having improved refill characteristics, responsiveness at the time of continuous ejection, stable growth of bubbles, and stabilization of liquid droplets are achieved, and high-speed recording by high-speed liquid ejection and high image quality are achieved. Recording could be enabled.

The other effects of the present invention will be understood from the description of each embodiment.

The terms "upstream" and "downstream" used in the description of the present invention refer to the flow direction of the liquid from the liquid supply source to the discharge port through the bubble generation region (or movable member).
Alternatively, it is expressed as an expression regarding this structural direction.

The "downstream side" of the bubble itself is as follows.
It mainly represents a portion on the ejection port side of a bubble which is considered to directly act on ejection of a droplet. More specifically, with respect to the center of the bubble, the downstream side with respect to the flow direction and the structural direction,
Alternatively, it means bubbles generated in a region downstream of the area center of the heating element.

The term "substantially sealed" used in the description of the present invention means that the bubble does not slip through a gap (slit) around the movable member before the movable member is displaced when the bubble grows. Means

Further, the term "separation wall" in the present invention means, in a broad sense, a wall (which may include a movable member) interposed so as to divide a bubble generation region and a region directly communicating with the discharge port. In a narrow sense, it means that the flow path including the bubble generation area is separated from the liquid flow path that directly communicates with the discharge port, and mixing of the liquid in each area is prevented.

Further, the "free end" of the movable member referred to in the present invention includes a free end which is a downstream end of the movable member and its vicinity, and also includes a vicinity of a downstream corner of the movable member. Means. Further, the "free end region" of the movable member in the present invention means any one of the free end itself, which is the downstream end of the movable member, or the vicinity of the free end, or the region where the free end and the side end are combined. ing.

The “resistance of the liquid flow path with respect to the movable member” in the present invention refers to the resistance of the liquid in the liquid flow path when the movable member moves away from the bubble generation region as bubbles are generated. Means the resistance applied to the movable member. Therefore, the present invention, by changing this resistance, that is, by having a resistance gradient, or by using the resistance of a physical stopper or the resistance of a substantial stopper with a liquid interposed,
It includes all technical contents for controlling the behavior of the movable member. Hereinafter, this resistance is simply expressed as “resistance” or “flow resistance”.

[0047]

BEST MODE FOR CARRYING OUT THE INVENTION

(Ejection Principle) A liquid ejection head applied to the present invention based on a new ejection principle will be described.

First, an example in which the direction of propagation of pressure based on bubbles for ejecting liquid and the direction of growth of bubbles are controlled to improve the ejection force and ejection efficiency will be described.

FIG. 1 is a schematic cross-sectional view of the liquid discharge head applied to the present invention cut in the liquid flow direction, and FIG. 2 is a partially cutaway perspective view of the liquid discharge head. .

The liquid discharge head applied to the present invention has a heating element 2 (in this embodiment, a heating resistor having a shape of 40 μm × 105 μm) acting as a discharge energy generating element for discharging the liquid. Is provided on the element substrate 1, and the heating element 2 is provided on the element substrate.
The liquid flow path 10 is arranged corresponding to the above. The liquid flow path 10 communicates with the discharge port 18 and also communicates with a common liquid chamber 13 for supplying the liquid to the plurality of liquid flow paths 10, and an amount of liquid corresponding to the liquid discharged from the discharge port. From the common liquid chamber 13.

A plate-shaped movable member 31 made of an elastic material such as metal and having a flat portion is provided on the element substrate of the liquid flow path 10 so as to face the heating element 2.
Are provided in a cantilever shape. One end of the movable member is fixed to a base (supporting member) 34 formed by patterning a photosensitive resin or the like on the wall of the liquid flow path 10 or the element substrate. Thus, the movable member is held and forms a fulcrum (fulcrum portion) 33.

The movable member 31 has a fulcrum (fulcrum portion; fixed end) 33 on the upstream side of a large flow flowing from the common liquid chamber 13 to the discharge port 18 through the movable member 31 by the liquid discharging operation. 33 is disposed at a position facing the heating element 2 at a distance of about 15 μm from the heating element so as to cover the heating element 2 so as to have a free end (free end portion) 32 on the downstream side with respect to 33. I have. A space between the heating element and the movable member is a bubble generation area. Note that the types, shapes, and arrangements of the heating element and the movable member are not limited thereto, and may be any shape and arrangement that can control the growth of bubbles and the propagation of pressure as described later. Note that the above-described liquid flow path 10
In order to explain the flow of the liquid to be discussed later, the movable member 31
The portion directly connected to the discharge port 18 with the boundary as the first liquid flow path 14 is divided into two areas of the bubble generation area 11 and the second liquid flow path 16 having the liquid supply path 12 for explanation. I do.

The movable member 31 is generated by causing the heating element 2 to generate heat.
Heat is applied to the liquid in the bubble generation region 11 between the heater and the heating element 2 to generate bubbles in the liquid based on the film boiling phenomenon as described in US Pat. No. 4,723,129. The pressure based on the generation of the air bubbles and the air bubbles act preferentially on the movable member, and the movable member 31 opens largely toward the discharge port around the fulcrum 33 as shown in FIG. 1 (b), (c) or FIG. To be displaced. Depending on the displacement or the displaced state of the movable member 31, the propagation of pressure based on the generation of bubbles and the growth of the bubbles themselves are guided to the ejection port side.

Here, one of the basic ejection principles applied to the present invention will be described. One of the most important principles in the present invention is that a movable member arranged to face a bubble is a first member in a steady state based on the pressure of the bubble or the bubble itself.
Is displaced from the position (1) to the second position, which is the position after the displacement, and the pressure accompanying the generation of bubbles and the bubbles themselves are guided by the displaceable movable member 31 to the downstream side where the discharge port 18 is arranged.

This principle will be described in more detail by comparing FIG. 3 schematically showing a conventional liquid flow path structure without using a movable member with FIG. 4 of the present invention. Here, the propagation direction of the pressure toward the discharge port is V _A , and the propagation direction of the pressure toward the upstream side is V _B
As shown.

A conventional head as shown in FIG.
The direction of pressure propagation by the generated bubbles 40
There is no configuration. Therefore, the pressure propagation direction of the bubble 40 is V₁
~ V₈As shown in the figure, the direction is perpendicular to the bubble surface.
I was right. Among them, it has the greatest effect on liquid ejection
V_AA component having a component in the pressure propagation direction in the direction₁~ V_Four
That is, the pressure of the part closer to the discharge port than the position of almost half of the bubble
Direction component of propagation, liquid discharge efficiency, liquid discharge force, discharge speed
This is an important part that directly contributes to the degree. Further V ₁Is a vomit
Outgoing direction V_AWorks efficiently because it is closest to the direction of_Four
Is V_AThe direction component toward is relatively small.

On the other hand, in the case of the present invention shown in FIG. 4, the movable member 31 moves downstream in the pressure propagation directions V _{1 to} V ₄ of the bubbles which have been oriented in various directions as in the case of FIG. Side (discharge port side), and converts the pressure into the _VA propagation direction, whereby the pressure of the bubbles 40 directly and efficiently contributes to the discharge. Then, the bubble growth direction itself is guided in the downstream direction similarly to the pressure propagation directions V _{1 to} V _4, and grows more downstream than upstream. As described above, by controlling the growth direction itself of the bubble by the movable member and controlling the pressure propagation direction of the bubble, it is possible to achieve a fundamental improvement in the discharge efficiency, the discharge force, the discharge speed, and the like.

Next, returning to FIG. 1, the discharge operation of the liquid discharge head of this embodiment will be described in detail.

FIG. 1A shows a state before energy such as electric energy is applied to the heating element 2 and a state before the heating element generates heat. What is important here is that the movable member 31 is provided at a position facing at least a downstream portion of the bubble generated by the heat generated by the heating element. In other words, on the liquid flow path structure, at least downstream of the area center 3 of the heating element (from a line passing through the area center 3 of the heating element and orthogonal to the length direction of the flow path, so that the downstream side of the bubble acts on the movable member. The movable member 31 is arranged to the position (downstream).

FIG. 1B shows that the heating element 2 generates heat when electric energy or the like is applied to the heating element 2, and the generated heat heats a part of the liquid filling the bubble generation region 11 to cause film boiling. This is a state in which accompanying air bubbles are generated.

At this time, the movable member 31 is displaced from the first position to the second position by the pressure based on the generation of the bubble 40 so as to guide the pressure propagation direction of the bubble 40 toward the discharge port. What is important here is that, as described above, the free end 32 of the movable member 31 is arranged on the downstream side (discharge port side), and the fulcrum 33 is arranged on the upstream side (common liquid chamber side). That is, at least a part of the movable member faces a downstream portion of the heating element, that is, a downstream portion of the bubble.

FIG. 1C shows a state in which the bubbles 40 have further grown, but the movable member 31 has been further displaced in accordance with the pressure accompanying the generation of the bubbles 40. The generated bubble grows greatly downstream from the upstream and grows greatly beyond the first position (dotted line position) of the movable member. Thus, bubble 4
When the movable member 31 is gradually displaced in accordance with the growth of 0, the pressure propagation direction of the bubble 40 and the direction in which the deposition is easily moved, that is, the growth direction of the bubble to the free end side is uniformly directed to the discharge port. It can be considered that being able to change the height also enhances the discharge efficiency. The movable member rarely hinders the transmission of bubbles or foaming pressure toward the discharge port, and efficiently controls the direction of pressure propagation and the direction of bubble growth according to the magnitude of the propagating pressure. Can be.

FIG. 1D shows a state in which the bubble 40 contracts and disappears due to the decrease in the internal pressure of the bubble after the above-mentioned film boiling.

The movable member 31 displaced to the second position
Is the initial position (first position) in FIG. 1A due to the negative pressure due to the contraction of the bubble and the restoring force due to the spring property of the movable member itself.
Return to. Further, at the time of defoaming, V _{D1 of} the flow from the upstream side (B), that is, the common liquid chamber side, to compensate for the contracted volume of the bubbles in the bubble generation region 11 and to supplement the volume of the discharged liquid. like the V _D2, also come flows liquid as V _C of the flow from the discharge port side.

The operation of the movable member and the discharge operation of the liquid accompanying the generation of bubbles have been described above. The liquid refill in the liquid discharge head applied to the present invention will be described in detail below.

The liquid supply mechanism of the present invention will be described in more detail with reference to FIG.

When the bubble 40 enters the defoaming process after passing through the state of the maximum volume after the state shown in FIG. 1 (c), a liquid having a volume supplementing the defoamed volume is placed in the bubble generation region in the first liquid flow path 14. The liquid flows from the discharge port 18 side and the common liquid chamber side 13 of the second liquid flow path 16. In the conventional liquid flow path structure without the movable member 31, the amount of the liquid flowing from the discharge port side to the defoaming position and the amount of the liquid flowing from the common liquid chamber are the same as the part closer to the discharge port than the bubble generation region and the common liquid. This is due to the magnitude of the flow resistance with the part close to the chamber (based on the flow path resistance and the inertia of the liquid).

Therefore, when the flow resistance on the side close to the discharge port is small, a lot of liquid flows from the discharge port side to the defoaming position, and the retreat amount of the meniscus becomes large. In particular, as the flow resistance on the side close to the discharge port is reduced to increase the discharge efficiency in order to increase the discharge efficiency, the meniscus M at the time of defoaming becomes larger, the refill time becomes longer, and the refill time becomes longer, and high-speed printing is performed. Was to hinder.

On the other hand, in the present configuration, since the movable member 31 is provided, when the volume W of the bubble is W1 on the upper side of the first position of the movable member 31 and W2 is on the bubble generation region 11 side, when the bubble disappears, Silence the retraction of the meniscus at the time when the movable member returns to the original position, the liquid supply for the volume of the subsequent remaining W2 is made mainly by the liquid supply from the flow V _D2 in the second flow path 16. Thus, while the amount corresponding to about half of the volume of the bubble W has conventionally been the meniscus retraction amount, it has become possible to suppress the meniscus retreat amount to a smaller amount, which is about half of W1.

Further, the supply of the liquid for the volume of W2 is forcibly performed mainly from the upstream side (V _D2 ) of the second liquid flow path along the surface of the movable member 31 on the side of the heating element using the pressure at the time of defoaming. Faster refill was realized because of the efficient refilling.

The characteristic feature here is that when refilling is performed using the pressure at the time of defoaming with the conventional head, the vibration of the meniscus becomes large and the image quality is deteriorated. In the high-speed refill, the flow of the liquid on the discharge port side between the area of the first liquid flow path 14 on the discharge port side and the bubble generation area 11 is suppressed by the movable member, so that the vibration of the meniscus can be extremely reduced. It is.

As described above, the present structure achieves the high-speed refill by forcibly refilling the foaming region via the liquid supply passage 12 of the second flow passage 16 and suppressing the meniscus retreat and vibration as described above. When used in the fields of stable printing, high-speed repetitive ejection, and printing, improvement in image quality and high-speed printing can be realized.

The configuration of the present invention further has the following effective functions. That is, the propagation of the pressure to the upstream side (back wave) due to the generation of bubbles is suppressed. Of the bubbles generated on the heating element 2, most of the pressure caused by the bubbles on the common liquid chamber 13 side (upstream side) is a force (back wave) for pushing back the liquid toward the upstream side.
This back wave caused the pressure on the upstream side, the amount of liquid movement due thereto, and the inertia force accompanying the liquid movement, which reduced the refill of the liquid into the liquid flow path and hindered high-speed driving. . In the present invention, first, the movable member 31
By suppressing these effects on the upstream side, the refill supply property is further improved.

Next, further characteristic structures and effects of the present configuration will be described below.

The second liquid flow path 16 of this configuration has a liquid supply path 12 having an inner wall that is substantially upstream of the heating element 2 and that is connected to the heating element 2 substantially flat (the heating element surface is not greatly reduced). ing. In such a case, the supply of the liquid to the bubble generation region 11 and the heat generating element 2 surface along the side surface closer to the bubble generation region 11 of the movable member 31 is performed as V _D2. Therefore, stagnation of the liquid on the surface of the heating element 2 is suppressed, and the deposition of gas dissolved in the liquid and the so-called residual air bubbles that cannot be defoamed are easily removed.
The heat stored in the liquid does not become too high. Therefore, more stable generation of bubbles can be repeated at high speed. In this configuration, the liquid supply path 12 having a substantially flat inner wall has been described. However, the present invention is not limited to this. Any liquid supply path that has a gentle inner wall that is smoothly connected to the surface of the heating element may be used. Any shape that does not cause stagnation of the liquid on the heating element or large turbulence in the supply of the liquid may be used.

In some cases, the supply of the liquid to the bubble generation region is performed from _VD1 through the side of the movable member (slit 35). However, in order to more effectively guide the pressure at the time of bubble generation to the discharge port, a large movable member is used so as to cover the entire bubble generation region (cover the heating element surface) as shown in FIG. by return to the position, in the case of forms, such as the flow resistance of the liquid becomes large between the region near the the bubble generation region 11 discharge ports of the first liquid flow path 14, the bubble generating area 11 from the aforementioned V _D1 Incoming liquid flow is impeded. However, in the head structure applied to the present invention, the flow V _D1 for supplying the liquid to the bubble generation region is used.
Therefore, the liquid supply performance becomes extremely high, and the liquid supply performance is not deteriorated even if a structure is required to improve the discharge efficiency such that the movable member 31 covers the bubble generation region 11.

The position of the free end 32 and the fulcrum 33 of the movable member 31 is such that the free end is relatively downstream from the fulcrum, as shown in FIG. With such a configuration, it is possible to efficiently realize functions and effects such as guiding the pressure propagation direction and growth direction of bubbles to the ejection port side during the above-described foaming. Further, this positional relationship achieves not only a function and an effect on discharge, but also an effect that the flow resistance to the liquid flowing through the liquid flow path 10 can be reduced and the refill can be performed at a high speed even when the liquid is supplied. As shown in FIG. 5, when the meniscus M retracted by the discharge returns to the discharge port 18 by capillary force or when liquid is supplied to the defoaming, the liquid flow path 10 (the first liquid (Including the flow path 14 and the second liquid flow path 16).
This is because the free end and the fulcrum 33 are arranged so as not to go against each other.

Supplementally, in the example of FIG. 1, as described above, the free end 32 of the movable member 31 is divided into the area center 3 (the heating element 2) that divides the heating element 2 into an upstream area and a downstream area. Line passing through the area center (center) and orthogonal to the length direction of the liquid flow path)
It extends with respect to the heating element 2 so as to face a position further downstream. As a result, the movable member 31 receives a pressure or a bubble that greatly contributes to the discharge of the liquid generated downstream of the area center position 3 of the heating element, and the pressure and the bubble can be guided to the discharge port side, and the discharge efficiency and the like can be improved. Discharge force can be fundamentally improved.

Further, many effects are obtained by utilizing the upstream side of the bubble.

Further, in the structure of the present embodiment, the fact that the free end of the movable member 31 performs an instantaneous mechanical displacement is also considered to contribute effectively to the ejection of the liquid.

The liquid discharge head according to the present invention based on the new discharge principle has been described above. Hereinafter, embodiments which can be preferably applied to the liquid discharge head will be described with reference to the drawings. However, in the following description, the aforementioned 1
Although there is a case where either one of the flow path form and the two flow path form is described, the present invention can be applied to both forms unless otherwise specified.

<Ceiling Shape of Liquid Flow Path> FIG. 6 is a cross-sectional view in the flow direction of the liquid discharge head of the present invention.
A grooved member 50 provided with a groove for constituting (or the liquid flow path 10 in FIG. 1) is provided on the separation wall 30. In this embodiment, the free end 3 of the movable member 31
The height of the flow path ceiling near the two positions is increased so that the operation angle θ of the movable member can be made larger. The operation range of the movable member may be determined in consideration of the structure of the liquid flow path, durability and bubbling force of the movable member, but it is desirable that the movable member be operated up to an angle including the angle in the axial direction of the discharge port. Conceivable.

Further, as shown in this figure, by making the displacement height of the free end of the movable member higher than the diameter of the discharge port,
A more sufficient transmission of the discharge force is achieved. As shown in this figure, the height of the liquid flow path ceiling at the fulcrum 33 of the movable member is lower than the height of the liquid flow path ceiling at the free end 32 of the movable member. The escape of the pressure wave to the upstream side due to the displacement can be more effectively prevented.

<Arrangement Relationship Between Second Liquid Flow Path and Movable Member> FIG. 7 is a diagram for explaining the arrangement relation between the movable member 31 and the second liquid flow path 16 described above. a) is a separation wall 3
FIG. 2B is a view of the vicinity of the movable member 31 as viewed from above, and FIG. 3B is a view of the second liquid flow path 16 from which the separation wall 30 has been removed, as viewed from above. FIG. 3C shows the movable member 31.
FIG. 4 is a diagram schematically illustrating an arrangement relationship between a first liquid flow path and a second liquid flow path by overlapping these elements. In each of the figures, the lower part of the drawing is the front side where the discharge ports are arranged.

The second liquid flow path 16 of this embodiment is located upstream of the heating element 2 (here, the upstream side is discharged from the second common liquid chamber side through the position of the heating element, the movable member, and the first flow path). A chamber having a constriction 19 at the upstream side of the large flow toward the outlet to suppress the pressure at the time of foaming from easily escaping to the upstream side of the second liquid flow path 16. (Foaming chamber) structure.

As in the conventional head, the flow path for bubbling and the flow path for discharging the liquid are the same, and a constricted portion is formed so that the pressure generated on the liquid chamber side from the heating element does not escape to the common liquid chamber side. In the case of the head provided with the above, it is necessary to adopt a configuration in which the cross-sectional area of the flow path in the constricted portion does not become so small in consideration of liquid refilling.

However, in the case of this embodiment, most of the liquid to be discharged can be used as the discharge liquid in the first liquid flow path, and the amount of the foaming liquid in the second liquid flow path provided with the heating element is too small. Since it can be prevented from being consumed, the filling amount of the foaming liquid into the bubble generation region 11 of the second liquid flow path 16 may be small. Therefore, since the interval in the constricted portion 19 can be made very small, that is, several μm to several tens of μm, it is possible to further suppress the pressure at the time of foaming generated in the second liquid flow path from being released too much to the surroundings, and to concentrate and move. It can be turned to the member side. Since this pressure can be used as the discharge force via the movable member 31, higher discharge efficiency and discharge force can be achieved. However, the shape of the first liquid flow path 16 is not limited to the above-described structure, and may be any shape as long as the pressure accompanying the generation of bubbles can be effectively transmitted to the movable member side.

As shown in FIG. 7 (c), the side of the movable member 31 covers a part of the wall constituting the second liquid flow path. Dropping into the liquid flow path can be prevented. This can further enhance the separability between the ejection liquid and the foaming liquid described above. Also,
Since the escape of bubbles from the slit can be suppressed, the discharge pressure and the discharge efficiency can be further increased. Further, the effect of refilling from the upstream side by the pressure at the time of defoaming can be enhanced.

In FIG. 1C and FIG. 6, bubbles generated in the bubble generation region of the second liquid flow path 16 due to the displacement of the movable member 31 toward the first liquid flow path 14 are shown. Some are first
However, by setting the height of the second flow path such that the bubbles extend, the ejection force can be further improved as compared with the case where the bubbles do not extend. be able to.
In order for the bubbles to extend into the first liquid flow path 14 in this manner, it is desirable that the height of the second liquid flow path 16 be lower than the height of the maximum bubble. μm to 30μ
m is desirable. In this embodiment, the height is set to 15 μm.

<Arrangement Relationship Between Bubble Generation Area and Heating Element> [Example 1] FIG. 8 shows a conceptual arrangement relation between a heating element and a bubble generation area, and FIG. 9 shows the heating element and air bubble generation in this embodiment. The arrangement of the areas is shown. The size of the heating element 2 in FIG.
× 150 μm, dimensions of the movable member 31 are 53 × 220 μ
m, the height of the second liquid flow path 16 is 15 μm, and the width is 62 μm
The dimensions of the heating element 2 in FIG.
m, the dimension of the movable member 31 is 53 × 220 μm, the height of the second liquid flow path 16 is 15 μm, and the width is 58 μm. FIG. 9 of the present embodiment differs from FIG. 8 in that the width of the second liquid flow path is different and is the same as the width of the heating element.

In FIG. 8, the pressure propagation directions of the bubbles 40 generated in the bubble generation region 16 are indicated by V _{1 to} V ₄ . The pressure reaches the movable member 31 while spreading in all directions.

In the present embodiment shown in FIG. 9, the center of the width of the bubble generating region 16 and the center of the width of the heating element 2 are the same (the same applies to the following embodiments). This is the arrangement relationship of (body width). In FIG. 8, the pressures V ₃ and V ₄ spreading on the sides are more easily transmitted upward in FIG. 9 due to the wall of the second liquid flow path. Therefore, the pressure due to the foaming is transmitted to the movable member without waste, and is converted into the discharge force, so that the discharge efficiency is improved.

Further, by adopting the structure as in this embodiment, the pitch of the nozzles can be increased, and the image quality can be remarkably improved.

[Embodiment 2] FIG. 10 shows an arrangement relationship between a heat generating pair and a bubble generation region according to Embodiment 2. The dimensions of the heating element 2 in FIG. 10 are 58 × 150 μm, the dimensions of the movable member 31 are 53 × 220 μm, and the height of the second liquid flow path 16 is 15 μm.
m, and the width is 50 μm. In the second embodiment, the width of the second liquid flow path is as narrow as 50 μm as compared with the first embodiment, and the relationship between the heating element 2 and the bubble generation region 16 is (width of the bubble generation region) = (heat generation). Body width) -8 μm.

By giving energy such as heat to the ink, a state change accompanied by a steep volume change (generation of bubbles) is caused in the ink, and the ink is ejected from the ejection port by the action force based on this state change. In the related art of an ink jet recording method for forming an image by adhering a liquid on a recording medium, that is, a so-called bubble jet recording method, FIG.
As shown in FIG. 3, although the heating element area and the ink discharge amount are in a proportional relationship, it can be seen that there is a non-foaming effective region S that does not contribute to ink discharge. In addition, from the appearance of the kogation on the heating element, it can be seen that the non-foaming effective area S exists around the heating element. From these results, it is considered that the width of about 4 μm around the heating element is not involved in foaming.

Therefore, if the heating element has a size of x μm in width and y μm in height, the relationship of (effective foaming area) = (x−8) (y−8) μm ² is established.

In the present embodiment, the effective foaming area is set at about 4 μm or more inside the periphery of the heating element. However, the present invention is not limited to this type depending on the type of heating element and the forming method.

Therefore, in the present embodiment, by adopting the arrangement shown in FIG. 10, the pressure propagation of the bubbles is converted into the discharge force without waste, and the discharge efficiency is improved.

Further, basically, even if the effective foaming area is the same, the discharge efficiency changes depending on the size of the heating element.
μm) = (vertical y μm) is ideal.

Therefore, with respect to the high density, it is possible to further increase the density by one step from the nozzle pitch, which is considered to be the limit, from the possible horizontal size of the heating element determined by the nozzle pitch and the area of the heating element required for ejection. It became.

The ejection efficiency was measured using the head of Example 2. The measurement conditions are as follows.

Bubbling liquid: 40% aqueous solution of ethanol Ejection ink: dye ink Voltage: 20.2 V Frequency: 3 kHz

As a result of conducting an experiment under these measurement conditions, it was confirmed that the kinetic energy based on the discharge amount and the discharge speed with respect to the input energy was remarkably improved as compared with the conventional head having no movable member.

[Embodiment 3] FIG. 11 shows an arrangement relationship between a heat generating pair and a bubble generation region in Embodiment 3.

The size of the heating element 2 in FIG. 11 is 58 × 1
The size of the movable member 31 is 53 × 150 μm, the height of the second liquid flow path 16 is 15 μm, and the width is 50 μm.

The relationship between the width of the heating element and the width of the bubble generation area is the same as that of the second embodiment, but the relationship between the length of the heating element and the length of the bubble generation area is different from that of the second embodiment. Sa)
= (Length of heating element)-8 m.

With such a positional relationship, the foaming chamber in the bubble generating region is constituted only by the heating element that effectively foams, so that the pressure propagation of the generated bubble is transmitted to the movable member without waste and the discharge force is reduced. , The discharge efficiency is improved.

Further, even if the discharged liquid is weak to heat and deposits are easily formed on the heating element, and the discharged liquid and the foaming liquid are different from each other, the movable member can be formed by adopting such a structure. Since the bubble generation region is filled with the bubbles while the liquid is displaced, the discharge liquid and the foaming liquid are not easily mixed. Further, by making the size of the movable member larger than the size of the bubble generation region, the airtightness of the bubble generation region is improved, and mixing of the discharge liquid and the foaming liquid is prevented.

<Movable Member and Separation Wall> FIG. 12 shows another shape of the movable member 31. Reference numeral 35 denotes a slit provided in the separation wall, and the slit forms the movable member 31. . (A) is a rectangular shape, (b) is a shape where the fulcrum side is narrower and the movable member is easy to operate, and (c) is a shape where the fulcrum side is wider and the movable member is wider. This is a shape that improves the durability of the device.
FIG. 7A shows a shape having good operability and durability.
As shown in the above, it is desirable that the width on the fulcrum side is narrowed in an arc shape, but the shape of the movable member is a shape that can be easily operated without entering the second liquid flow path side and has a durability. Any shape that is excellent in shape is acceptable.

In the above embodiment, the plate-like movable member 31
And the separation wall 20 having this movable member has a thickness of 5 μm.
However, the material of the movable member and the separation wall is not limited to this, but has solvent resistance to the foaming liquid and the discharge liquid, and has elasticity to operate well as the movable member. However, any material can be used as long as a fine slit can be formed.

As the material of the movable member, high durability
Metals such as silver, nickel, gold, iron, titanium, aluminum, platinum, tantalum, stainless steel, phosphor bronze, and alloys thereof, or resins having a nitrile group such as acrylonitrile, butadiene, styrene, and amide groups such as polyamide Resin, resin having a carboxyl group such as polycarbonate, resin having an aldehyde group such as polyacetal, resin having a sulfone group such as polysulfone,
In addition, resins and compounds such as liquid crystal polymers, highly ink-resistant metals such as gold, tungsten, tantalum, nickel, stainless steel, titanium, alloys of these and those with ink resistance coated on the surface or polyamide A resin having an amide group such as
Resins having an aldehyde group such as polyacetal, resins having a ketone group such as polyetheretherketone, resins having an imide group such as polyimide, resins having a hydroxyl group such as a phenol resin, resins having an ethyl group such as polyethylene, polypropylene, etc. A resin having an alkyl group, a resin having an epoxy group such as an epoxy resin, a resin having an amino group such as a melamine resin, a resin having a methylol group such as a xylene resin and its compound, and a ceramic such as silicon dioxide and its compound. desirable.

Examples of the material of the separation wall include polyethylene, polypropylene, polyamide, polyethylene terephthalate, melamine resin, phenol resin, epoxy resin, polybutadiene, polyurethane, polyetheretherketone, polyethersulfone, polyarylate, polyimide, polysulfone, and liquid crystal. A resin having good heat resistance, solvent resistance and moldability represented by recent engineering plastics such as polymer (LCP) and its compound, or silicon dioxide, silicon nitride, nickel,
Metals such as gold and stainless steel, alloys and their compounds, or those whose surfaces are coated with titanium or gold are desirable.

The thickness of the separation wall may be determined in consideration of the material and shape thereof from the viewpoint that the strength as the separation wall can be achieved and the movable member operates well.
A thickness of about 0.5 to 10 μm is desirable.

The width of the slit 35 for forming the movable member 31 is 2 μm in the present embodiment. However, if the foaming liquid and the discharge liquid are different liquids and it is desired to prevent a mixture of the two liquids, the slit 35 is used. The width may be set so as to form a meniscus between the two liquids, and the flow of each liquid may be suppressed. For example, when a liquid of about 2 cp (centipoise) is used as the foaming liquid and a liquid of 100 cp or more is used as the ejection liquid, the liquid mixture can be prevented even with a slit of about 5 μm, but it is preferably 3 μm or less. .

The movable member in the present invention is intended for a thickness on the order of μm (t μm), and a movable member having a thickness on the order of cm is not intended. For a movable member having a thickness on the order of μm, a slit width (W
μm), it is desirable to consider the manufacturing variation to some extent.

When the thickness of the member facing the free end and / or the side end of the movable member forming the slit is equal to the thickness of the movable member (FIG. 12, FIG. 6, etc.), the relationship between the slit width and the thickness is determined by manufacturing. By setting the following range in consideration of the variation, the mixture of the foaming liquid and the ejection liquid can be stably suppressed. Although this is a limited condition, as a design point of view, when a high-viscosity ink (5 cp, 10 cp, etc.) is used for a foaming liquid having a viscosity of 3 cp or less, W / t ≦
By satisfying the condition 1, the mixing of the two liquids can be suppressed for a long time.

The slit that provides the “substantially sealed state” of the present invention is more reliable if it is on the order of several μm.

As described above, when the functions are separated into the foaming liquid and the discharging liquid, the movable member becomes a substantial partitioning member. It can be seen that the foaming liquid mixes slightly with the discharge liquid when the movable member moves with the generation of bubbles. In consideration of the fact that an ejection liquid for forming an image generally has a colorant density of about 3% to 5% in the case of ink jet recording, this foaming liquid is in a range of 20% or less with respect to the ejection droplet. Does not cause a large change in concentration. Therefore, the present invention includes such a mixed liquid as a mixture of a foaming liquid and an ejected liquid such that the amount thereof is 20% or less of the ejected liquid droplets.

In the implementation of the above configuration example, even if the viscosity is changed, the mixing of the foaming liquid at the upper limit of 15% is performed. For the foaming liquid of 5 cps or less, the mixing ratio depends on the driving frequency, but is 10%. % As the upper limit.

In particular, as the viscosity of the discharged liquid is set to 20 cps or less, the mixed liquid can be reduced (for example, 5% or less).

Next, the positional relationship between the heating element and the movable member in the head will be described with reference to the drawings. However,
The shapes, dimensions, and numbers of the movable member and the heating element are not limited to the following. By the optimal arrangement of the heating element and the movable member, the pressure at the time of foaming by the heating element can be effectively used as the discharge pressure.

As described above, there is a non-foaming effective area around the heating element, and it is considered that the width of about 4 μm around the heating element is not involved in foaming.

Therefore, in order to effectively use the foaming pressure, it is effective to dispose the movable member such that the movable region of the movable member covers the area just above the effective foaming area at least about 4 μm from the periphery of the heating element. It can be said that it is a target.

FIG. 14 shows a movable member 301 ((a)) having a different total area of movable regions on a heating element 2 of 58 × 150 μm.
FIG. 2 is a schematic diagram viewed from above when the movable member 302 (FIG. 2B) is arranged.

The size of the movable member 301 is 53 × 145 μm.
m, which is smaller than the area of the heating element 2, but approximately the same as the effective foaming area of the heating element 2, and is arranged so as to cover the effective foaming area. On the other hand, the size of the movable member 302 is 53 × 220 μm, which is larger than the area of the heating element 2 (when the width is the same, the dimension between the fulcrum and the movable tip is longer than the length of the heating element). It is arranged so as to cover the effective foaming area in the same manner as the above. The durability and discharge efficiency of the two types of movable members 301 and 302 were measured. The measurement conditions are as follows.

Bubbling liquid: 40% aqueous solution of ethanol Discharge ink: Dye ink Voltage: 20.2 V Frequency: 3 kHz

As a result of an experiment conducted under these measurement conditions, regarding the durability of the movable member, (a) the movable member 301
When 1 × 10 ⁷ pulses were applied, damage was observed at the fulcrum portion of the movable member 301. (B) No damage was seen on the movable member 302 even when 3 × 10 ⁸ pulses were applied. It was also confirmed that the kinetic energy based on the discharge amount and the discharge speed with respect to the input energy was improved by about 1.5 to 2.5 times.

From the above results, from the viewpoints of both durability and discharge efficiency, it is preferable that the movable member is provided so as to cover directly above the effective foaming area, and that the area of the movable member is larger than the area of the heating element. It turns out that it is excellent.

FIG. 15 shows the relationship between the distance from the edge of the heating element to the fulcrum of the movable member and the amount of displacement of the movable member. FIG. 16 is a sectional view showing the positional relationship between the heating element 2 and the movable member 31 as viewed from the side. Heating element 2 is 40 ×
The one having a size of 105 μm was used. It can be seen that the greater the distance l from the edge of the heating element 2 to the fulcrum 33 of the movable member 31, the greater the displacement. Therefore, it is desirable to determine the optimal displacement amount and determine the position of the fulcrum of the movable member based on the required ink discharge amount, the discharge liquid flow path structure, and the shape of the heating element.

When the fulcrum of the movable member is located immediately above the effective foaming area of the heating element, the durability of the movable member is reduced because the foaming pressure is directly applied to the fulcrum in addition to the stress caused by the displacement of the movable member. . According to the experiment of the present inventor, it was found that, in the case where the fulcrum was provided right above the effective foaming area, the movable wall was damaged by about 1 × 10 ⁶ pulses, and the durability was reduced. I have. Therefore, by arranging the fulcrum of the movable member just above the effective foaming area of the heating element, the practicability increases even if the movable member has a shape or material whose durability is not so high. However, even if there is a fulcrum just above the effective foaming area, it can be used favorably if the shape and material are selected. With this configuration, a liquid ejection head having high ejection efficiency and excellent durability can be obtained.

<Element Substrate> The configuration of an element substrate provided with a heating element for applying heat to a liquid will be described below.

FIG. 17 is a longitudinal sectional view of the liquid discharge head of the present invention. FIG. 17A shows a head having a protective film described later, and FIG. 17B shows a head without the protective film.

On the element substrate 1, the second liquid flow path 16, the separation wall 3
0, a first liquid flow path 14, and a grooved member 50 provided with grooves forming the first liquid flow path.

The element substrate 1 contains a gas 107 such as silicon.
A silicon oxide film or a silicon nitride film 106 for insulation and heat storage is formed thereon, and hafnium boride (HfB ₂ ), tantalum nitride (TaN), and tantalum aluminum (TaAl) constituting a heating element are formed thereon. 17) and a wiring electrode (0.2 to 1.0 μm thick) of aluminum or the like are patterned as shown in FIG. These two wiring electrodes 10
From 4, a voltage is applied to the resistance layer 105, and a current flows through the resistance layer to generate heat. On the resistance layer between the wiring electrodes, a protective layer such as silicon oxide or silicon nitride is formed with a thickness of 0.1 to 2.0 μm, and further thereon, a cavitation resistant layer such as tantalum (with a thickness of 0.1 to 0.6 μm) is formed. ) Is deposited,
The resistance layer 105 is protected from various liquids such as ink.

In particular, the pressure and shock waves generated during the generation and defoaming of air bubbles are extremely strong, and significantly reduce the durability of a hard and brittle oxide film.
Are used as a cavitation-resistant layer.

A structure that does not require the above-mentioned protective layer may be used depending on the combination of the liquid, the liquid flow path structure, and the resistance material. An example thereof is shown in FIG. Examples of the material of the resistance layer that does not require such a protective layer include an iridium-tantalum-aluminum alloy.

As described above, the configuration of the heating element in each of the above-described embodiments may be only the above-described resistance layer (heating section) between the electrodes, or may include a protective layer for protecting the resistance layer.

In the present embodiment, a heating element having a heating section composed of a resistance layer that generates heat in response to an electric signal is used as the heating element. However, the heating element is not limited to this, and is sufficient to discharge the discharge liquid. What is necessary is just a thing which produces a bubble in a foaming liquid. For example, a light-to-heat converter that generates heat by receiving light from a laser or the like, or a heat generator that has a heat generating unit that generates heat by receiving a high frequency may be used as the heat generating unit.

The above-mentioned element substrate 1 includes, in addition to the electrothermal transducer composed of the above-described resistance layer 105 constituting the heating section and the wiring electrode 104 for supplying an electric signal to this resistance layer, Functional elements such as a transistor, a diode, a latch, and a shift register for selectively driving the electrothermal conversion element may be integrally formed by a semiconductor manufacturing process.

In order to drive the heat generating portion of the electrothermal transducer provided on the element substrate 1 as described above and discharge the liquid, a rectangular pulse is applied to the resistance layer 105 via the wiring electrode 104. Is applied to cause the resistance layer 105 between the wiring electrodes to generate heat sharply. In the head of each of the above embodiments,
Voltage 24 V, pulse width 7 μsec, current 150
The heating element was driven by applying an electric signal of mA at 6 kHz, and the liquid ink was ejected from the ejection port by the operation described above. However, the condition of the drive signal is not limited to this, and any drive signal can be used as long as it can appropriately foam the foaming liquid.

<Head Structure with Two Flow Channels> The liquid discharge which can satisfactorily separate and introduce different liquids into the first and second common liquid chambers, can reduce the number of parts, and can reduce the cost. An example of the structure of the head will be described.

FIG. 18 is a schematic diagram showing the structure of such a liquid discharge head, in which the same reference numerals are used for the same components as in the previous embodiment, and a detailed description is omitted here.

In this embodiment, the grooved member 50 is
An orifice plate 51 having a discharge port 18; a plurality of grooves forming a plurality of first liquid flow paths 14;
4 and a concave portion forming a first common liquid chamber 15 for supplying a liquid (discharge liquid) to each first liquid flow path 14.

The separation wall 30 is provided below the grooved member 50.
Can be formed to form a plurality of first liquid flow paths 14. Such a grooved member 50 has a first liquid supply path 20 that reaches the inside of the first common liquid chamber 15 from above. Further, the grooved member 50 penetrates the separation wall 30 from the upper part thereof and reaches the second common liquid chamber 17 in the second common liquid chamber 17.
The liquid supply path 21 of FIG.

The first liquid (discharge liquid) is indicated by arrow C in FIG.
As shown by, the liquid is supplied to the first common liquid chamber 15 and then to the first liquid flow path 14 via the first liquid supply path 20, and the second liquid (foaming liquid) is indicated by an arrow D in FIG. As shown, the second
Through the liquid supply path 21, the second common liquid chamber 17, and then the second common liquid chamber 17,
The liquid is supplied to the liquid flow path 16.

In this embodiment, the second liquid supply path 21
Is arranged in parallel with the first liquid supply passage 20, but is not limited to this, penetrates the separation wall 30 arranged outside the first common liquid chamber 15, and 17 may be arranged in any way as long as it is formed so as to communicate with 17.

The thickness (diameter) of the second liquid supply path 21
Is determined in consideration of the supply amount of the second liquid.
The shape of the second liquid supply path 21 does not need to be round,
It may be rectangular or the like.

The second common liquid chamber 17 is provided with a grooved member 50.
By the partition wall 30. As a forming method, as shown in an exploded perspective view of the present embodiment shown in FIG. 19, a common liquid chamber frame and a second liquid path wall are formed on an element substrate with a dry film, and a grooved member in which a separation wall is fixed. The second common liquid chamber 17 and the second liquid flow path 16 may be formed by bonding the combined body of the separation wall 30 and the element substrate 1 to the element substrate 1.

In the present embodiment, as described above, as a heating element that generates heat for generating bubbles due to film boiling with respect to a foaming liquid, on a support 70 formed of a metal such as aluminum. An element substrate 1 provided with a plurality of electrothermal conversion elements is provided.

On the element substrate 1, a plurality of grooves forming the liquid flow path 16 formed by the second liquid path wall and a plurality of the foaming liquid flow paths are communicated. Forming a second common liquid chamber (common bubbling liquid chamber) 17 for supplying water, and a separation wall 30 provided with the movable wall 31 described above.
And are arranged.

Reference numeral 50 denotes a grooved member. The grooved member is joined to the separation wall 30 to form a discharge liquid flow path (first
A first common liquid chamber (common discharge liquid chamber) 15 which communicates with the groove forming the liquid flow path) 14 and the discharge liquid flow path to supply the discharge liquid to each discharge liquid flow path; Of the recess,
A first supply path (discharge liquid supply path) 20 for supplying discharge liquid to the first common liquid chamber, and a second supply path (foam liquid supply) for supplying foaming liquid to the second common liquid chamber 17. (Road) 21. The second supply passage 21 penetrates the separation wall 30 disposed outside the first common liquid chamber 15 and
7, the foaming liquid is not mixed with the discharge liquid by the communication path, and the foamed liquid is mixed with the second common liquid chamber 1.
5 can be supplied.

The arrangement relationship between the element substrate 1, the separation wall 30, and the grooved top plate 50 is such that the movable member 31 is arranged corresponding to the heating element of the element substrate 1, and corresponds to the movable member 31. A discharge liquid channel 14 is provided. Further, in the present embodiment, an example is shown in which one second supply path is provided in the grooved member, but a plurality of second supply paths may be provided according to the supply amount. Furthermore, the flow path cross-sectional area of the discharge liquid supply path 20 and the foaming liquid supply path 21 may be determined in proportion to the supply amount.

By optimizing the cross-sectional area of the flow path, it is possible to further reduce the size of the components constituting the grooved member 50 and the like.

As described above, according to this embodiment,
A second supply path for supplying the second liquid to the second liquid flow path;
Since the first supply path for supplying the first liquid to the liquid flow path is formed of the same grooved top plate as the grooved member, the number of components can be reduced, and the process can be shortened and the cost can be reduced.

The supply of the second liquid to the second common liquid chamber communicating with the second liquid flow path is performed by the second liquid flow path in a direction penetrating the separation wall separating the first liquid and the second liquid. Since the structure is performed, the bonding step of the separation wall, the grooved member, and the heating element forming substrate only needs to be performed once, thereby improving the ease of manufacturing, improving the bonding accuracy, and discharging well. Can be.

Further, since the second liquid penetrates through the separation wall and is supplied to the second liquid common liquid chamber, the supply of the second liquid to the second liquid flow path is ensured, and the supply amount can be sufficiently secured.
Stable discharge is possible.

<Ejecting Liquid and Foaming Liquid> As described in the previous embodiment, in the present invention, the structure having the above-described movable member enables the ejection force and the ejection efficiency to be higher than those of the conventional liquid ejection head. Moreover, the liquid can be discharged at a high speed. In the present invention, when the same liquid is used for the foaming liquid and the discharge liquid, the liquid is not deteriorated by heat applied from the heating element, and hardly causes deposits on the heating element by heating, and is vaporized and condensed by heat. It is possible to use various liquids as long as the liquid does not deteriorate the liquid flow path, the movable member, the separation wall, and the like.

Among such liquids, as a liquid (recording liquid) used for recording, ink having a composition used in a conventional bubble jet apparatus can be used.

On the other hand, when a head having a two-flow channel structure according to the present invention is used and the discharge liquid and the foaming liquid are different liquids, a liquid having the above-mentioned properties may be used as the foaming liquid. , Methanol, ethanol, n-propanol, isopropanol, n-hexane, n-heptane, n-octane, toluene, xylene, methylene dichloride, trichlene, Freon TF, Freon BF, ethyl ether, dioxane, cyclohexane, methyl acetate, acetic acid ethyl,
Examples include acetone, methyl ethyl ketone, water, and the like, and mixtures thereof.

As the discharge liquid, various liquids can be used irrespective of the presence or absence of foaming properties and thermal properties. In addition, liquids having low foaming properties, liquids which are easily deteriorated or deteriorated by heat, high-viscosity liquids, and the like, which have been difficult to discharge conventionally, can be used.

However, the properties of the discharged liquid are as follows:
Alternatively, it is desirable that the liquid is not a liquid that hinders ejection, foaming, operation of the movable member, or the like due to a reaction with the foaming liquid.

As the ejection liquid for recording, a high-viscosity ink or the like can also be used. As other discharge liquids, liquids such as medicines and perfumes that are vulnerable to heat can be used.

In the present invention, recording was carried out using an ink having the following composition as a recording liquid which can be used for both the ejection liquid and the foaming liquid. Therefore, the landing accuracy of the droplet was improved, and a very good recorded image could be obtained.

[0164]

[Outside 1]

In addition, recording was performed by discharging a liquid having the following composition in combination with the foaming liquid and the discharge liquid. As a result, more than ten cp that were difficult to eject with the conventional head
As a matter of course, even a liquid having a very high viscosity of 150 cp, as well as a liquid having a viscosity of s, could be ejected favorably, and a recorded matter of high quality could be obtained.

[0166]

[Outside 2]

By the way, in the case of the liquid which has been conventionally difficult to be ejected as described above, since the ejection speed is low, the dispersion of the ejection direction is promoted, and the landing accuracy of the dots on the recording paper is poor. Discharge amount variation due to instability occurred, and as a result, it was difficult to obtain high-quality images. However, in the configuration of the above-described embodiment, the generation of bubbles can be sufficiently and stably performed by using the foaming liquid. As a result, it is possible to improve the landing accuracy of the droplets and stabilize the ink discharge amount, and it is possible to remarkably improve the quality of the recorded image.

<Liquid Discharge Apparatus> FIG. 20 shows a schematic configuration of a liquid discharge apparatus equipped with the above-described liquid ejecting head. In the present embodiment, a carriage HC of a liquid ejection apparatus, which will be described using an ink ejection recording apparatus using ink as an ejection liquid, is a head cartridge in which a liquid tank section 90 containing ink and a liquid ejection head section 200 are detachable. And reciprocate in the width direction of the recording medium 150 such as recording paper conveyed by the recording medium conveying means.

When a drive signal is supplied from a drive signal supply means (not shown) to the liquid discharge means on the carriage, the recording liquid is discharged from the liquid discharge head to the recording medium in accordance with this signal.

Further, in the liquid discharge apparatus of this embodiment, the motor 111 as a drive source for driving the recording medium conveying means and the carriage, the gears 112 and 113 for transmitting the power from the drive source to the carriage. It has a shaft 115 and the like. With this recording apparatus and the liquid ejection method performed by this recording apparatus, a recorded matter of a good image could be obtained by ejecting liquid to various recording media.

FIG. 21 is a block diagram of an entire apparatus for operating ink discharge recording to which the liquid discharge method and liquid discharge head of the present invention are applied.

The recording device receives print information from the host computer 300 as a control signal. The print information is temporarily stored in an input interface 301 inside the printing apparatus, and at the same time, is converted into data that can be processed in the printing apparatus, and is input to the CPU 302 also serving as a head drive signal supply unit. The CPU 302 processes data input to the CPU 302 using a peripheral unit such as the RAM 304 based on a control program stored in the ROM 303,
Convert to print data (image data).

In order to record the image data at an appropriate position on the recording sheet, the CPU 302 generates drive data for driving a driving motor for moving the recording sheet and the recording head in synchronization with the image data. The image data and the motor drive data are respectively
The image is transmitted to the head 200 and the drive motor 306 via the motor driver 305, and is driven at a controlled timing to form an image.

The recording medium which can be applied to the recording apparatus as described above and to which a liquid such as ink is applied includes plastics, cloth, aluminum and the like used for various papers, OHP sheets, compact discs and decorative plates, etc. Metal materials such as copper and copper, leather materials such as cow skin, pig skin and artificial leather, wood such as wood and plywood, ceramic materials such as bamboo materials and tiles, and three-dimensional structures such as sponges can be targeted.

As the recording apparatus described above, various types of paper and O
A printer device for recording on an HP sheet or the like, a recording device for a plastic for recording on a plastic material such as a compact disc, a recording device for a metal for recording on a metal plate,
A recording device for leather for recording on leather, a recording device for wood for recording on wood, a recording device for ceramics for recording on ceramic materials, a recording device for recording on a three-dimensional network structure such as a sponge, and a cloth Also includes a textile printing device for performing recording on the paper.

As a discharge liquid used in these liquid discharge devices, a liquid suitable for each recording medium and recording conditions may be used.

[0177]

As described above, in the liquid discharge head according to the present invention, by setting (width of effective foaming area ≦ width of bubble generating area ≦ width of heating element), the generated bubbles are directed upward. Alternatively, it can be grown to the ejection port side. Thereby, the ejection force can be made more stable. Further, the density can be increased, and the image quality can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing an example of a liquid ejection head applied to the present invention.

FIG. 2 is a partially cutaway perspective view of a liquid ejection head applied to the present invention.

FIG. 3 is a schematic diagram showing pressure propagation from bubbles in a conventional head.

FIG. 4 is a schematic diagram showing pressure propagation from bubbles in a liquid ejection head applied to the present invention.

FIG. 5 is a schematic diagram for explaining a flow of a liquid in a liquid ejection head applied to the present invention.

FIG. 6 is a view for explaining a structure of a movable member and a first liquid flow path.

FIG. 7 is a view for explaining the structure of a movable member and a liquid flow path;

FIG. 8 is a view showing a conceptual arrangement of a heating element and a second liquid flow path;

FIG. 9 is a diagram illustrating an arrangement relationship between a heating element and a second liquid channel according to the first embodiment.

FIG. 10 is a diagram illustrating an arrangement relationship between a heating element and a second liquid channel according to a second embodiment.

FIG. 11 is a diagram illustrating an arrangement relationship between a heating element and a second liquid channel according to a third embodiment.

FIG. 12 is a view for explaining another shape of the movable member.

FIG. 13 is a diagram showing a relationship between a heating element area and an ink ejection amount.

FIG. 14 is a diagram showing an arrangement relationship between a movable member and a heating element.

FIG. 15 is a diagram illustrating a relationship between a distance between an edge of a heating element and a fulcrum and a displacement amount of a movable member.

FIG. 16 is a view for explaining an arrangement relationship between a heating element and a movable member.

FIG. 17 is a longitudinal sectional view of the liquid ejection head of the present invention.

FIG. 18 is a cross-sectional view for explaining a supply path of the liquid ejection head according to the present invention.

FIG. 19 is an exploded perspective view of a head according to the present invention.

FIG. 20 is a schematic configuration diagram of a liquid ejection apparatus of the present invention.

FIG. 21 is a block diagram of a recording apparatus according to the present invention.

FIG. 22 is a view for explaining a liquid flow path structure of a conventional liquid discharge head.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 element substrate 2 heating element 3 area center 10 liquid flow path 11 bubble generation area 12 supply path 13 common liquid chamber 14 first liquid flow path 15 first common liquid chamber 16 bubble foaming area (second liquid flow path) 17 second Common liquid chamber 18 Discharge port 19 Narrowed portion 20 First supply path 21 Second supply path 22 First liquid flow path wall 23 Second liquid flow path wall 24 Convex part 30 Separation wall 31 Movable member 32 Free end 33 Support point 34 Support member 35 Slit 36 Front wall of bubble generation area 37 Side wall of bubble generation area 40 Bubble 45 Droplet 50 Grooved member 51 Orifice plate 70 Support 78 Spring

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kiyomitsu Kudo 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Yoshie Asakawa 8248-7, Hodaka, Hodaka-cho, Minamiazumi-gun, Nagano Prefecture

Claims (60)

[Claims] 1. A discharge port for discharging a liquid, a bubble generation region for generating bubbles by applying heat to the liquid with a heating element,
A first position between the first position and the first position;
And a movable member that can be displaced between a second position farther from the bubble generation region than the position described above, and the movable member is configured to move the first member by pressure based on the generation of bubbles in the bubble generator. A liquid discharge head that discharges liquid by displacing the bubble from the position of the movable member to the second position, and expanding the bubble by a displacement of the movable member to a greater extent than an upstream in a direction toward a discharge port. There is something called a foaming area involved in foaming in the body,
A liquid discharge head characterized in that the width center of the heating element and the effective foaming area with respect to the flow direction of the liquid are equal, and the condition of the bubble generation area is: effective foaming area ≦ width of bubble generation area ≦ width of heating element. 2. The liquid discharge head according to claim 1, wherein: width of heating element−8 μm ≦ width of bubble generation region. 3. The liquid discharge head according to claim 1, wherein the flow direction of the liquid is the length direction of the heating element and the effective foaming area. A liquid discharge head, wherein length ≦ length of the heating element. 4. The liquid discharge head according to claim 1, wherein the area of the effective foaming area ≦ the area of the movable member, wherein the movable member seals the effective foaming area in a stationary state. Discharge head. 5. The displacement of the movable member causes a downstream portion of the bubble to grow downstream of the movable member.
Liquid ejection head. 6. The liquid ejection head according to claim 1, wherein the movable member has a fulcrum and a free end located downstream from the fulcrum. 7. A discharge port for discharging a liquid, a bubble generation region for generating bubbles in the liquid by applying heat to the liquid with a heating element, and the heat generation from an upstream side of the heating element along the heating element. A liquid flow path having a supply path for supplying a liquid onto the body, and a free end provided on the discharge port side facing the heating element, the free end being formed based on pressure generated by the bubble. A movable member that displaces the pressure to the discharge port side by displacing, wherein there is a heating element that is a foaming region that participates in foaming,
A liquid discharge head characterized in that the width center of the heating element and the effective foaming area with respect to the flow direction of the liquid are equal, and the condition of the bubble generation area is: effective foaming area ≦ width of bubble generation area ≦ width of heating element. 8. The liquid discharge head according to claim 7, wherein: width of heating element−8 μm ≦ width of bubble generation region. 9. The liquid discharge head according to claim 7, wherein the flow direction of the liquid is the length direction of the heating element and the effective foaming area. A liquid discharge head, wherein length ≦ length of the heating element. 10. The liquid discharge head according to claim 7, wherein the area of the effective foaming area ≦ the area of the movable member, wherein the movable member seals the effective foaming area in a stationary state. Discharge head. 11. A discharge port for discharging a liquid, a bubble generation region for generating bubbles in the liquid by applying heat to the liquid with a heating element, and a free end provided on the heating element and facing the discharge port. A movable member that has the free end displaced based on the pressure due to the generation of the bubbles and guides the pressure toward the discharge port side,
A liquid supply head for supplying liquid onto the heating element from an upstream side of the movable member along a surface close to the heating element, wherein the heating element is a foaming region involved in foaming. Exists,
A liquid discharge head characterized in that the width center of the heating element and the effective foaming area with respect to the flow direction of the liquid are equal, and the condition of the bubble generation area is: effective foaming area ≦ width of bubble generation area ≦ width of heating element. 12. The liquid discharge head according to claim 11, wherein: width of heating element−8 μm ≦ width of bubble generation region. 13. The liquid discharge head according to claim 11, wherein the flow direction of the liquid is the length direction of the heating element and the effective foaming area. A liquid discharge head, wherein length ≦ length of the heating element. 14. The liquid ejection head according to claim 11, wherein the area of the effective foaming area ≦ the area of the movable member, wherein the movable member seals the effective foaming area in a stationary state. Discharge head. 15. A second liquid flow path having a first liquid flow path communicating with a discharge port, a second liquid flow path having a bubble generation region for generating bubbles in the liquid by applying heat to the liquid by a heating element, and 1 is provided between the liquid flow path and the bubble generation region, has a free end on the discharge port side, and sets the free end to the first position based on pressure generated by bubbles in the bubble generation region. A movable member that displaces the pressure toward the liquid flow path side and guides the pressure toward the discharge port side of the first liquid flow path. ,
A liquid discharge head characterized in that the width center of the heating element and the effective foaming area with respect to the flow direction of the liquid are equal, and the condition of the bubble generation area is: effective foaming area ≦ width of bubble generation area ≦ width of heating element. 16. The liquid discharge head according to claim 15, wherein: width of heating element−8 μm ≦ width of bubble generation region. 17. The liquid discharge head according to claim 15, wherein the flow direction of the liquid is the length direction of the heating element and the effective foaming area. A liquid discharge head, wherein length ≦ length of the heating element. 18. The liquid ejection head according to claim 15, wherein the area of the effective foaming area ≦ the area of the movable member, wherein the movable member seals the effective foaming area in a stationary state. Discharge head. 19. The liquid discharge head according to claim 1, wherein a heating element is provided at a position facing the movable member, and a space between the movable member and the heating element is the bubble generation region. 20. The liquid discharge head according to claim 7, wherein the free end of the movable member is located downstream from the center of the area of the heating element. 21. The liquid discharge head according to claim 19, further comprising a supply path for supplying a liquid onto the heating element from the upstream of the heating element along the heating element. 22. The supply path, wherein the supply path has a substantially flat or gentle inner wall upstream of the heating element, and supplies the liquid onto the heating element along the inner wall. 7. The liquid discharge head according to claim 11 or claim 21. 23. The liquid ejection head according to claim 7, wherein the bubbles are bubbles generated by causing film boiling of the liquid by heat generated by the heating element. 24. The movable member according to claim 7, wherein the movable member has a plate shape.
The liquid ejection head according to claim 11 or claim 19. 25. The liquid discharge head according to claim 24, wherein all of the effective foaming regions of the heating element face the movable member. 26. The liquid discharge head according to claim 24, wherein the entire surface of the heating element faces the movable member. 27. The liquid discharge head according to claim 24, wherein a total area of the movable member is larger than a total area of the heating element. 28. The liquid discharge head according to claim 24, wherein a fulcrum of the movable member is disposed at a position deviated from immediately above the heating element. 29. The liquid discharge head according to claim 24, wherein a free end of the movable member has a shape substantially orthogonal to a liquid flow path in which the heating element is disposed. 30. The liquid discharge head according to claim 24, wherein the free end of the movable member is disposed closer to a discharge port than the heating element. 31. The liquid discharge head according to claim 15, wherein the movable member is configured as a part of a separation wall disposed between the first flow path and the second flow path. 32. The liquid discharge head according to claim 31, wherein the separation wall is made of a metal material. 33. The liquid discharge head according to claim 32, wherein the metal material is nickel or gold. 34. The liquid discharge head according to claim 31, wherein the separation wall is made of a resin. 35. The liquid discharge head according to claim 31, wherein the separation wall is made of ceramic. 36. A first common liquid chamber for supplying a first liquid to a plurality of the first liquid flow paths, and a second liquid for supplying a second liquid to a plurality of the second liquid flow paths. 16. The liquid discharge head according to claim 15, wherein the second common liquid chamber is disposed. 37. A plurality of discharge ports for discharging a liquid, a plurality of grooves for forming a plurality of first liquid flow paths directly communicating with the respective discharge ports, and the plurality of first liquid flow paths. A grooved member integrally having a concave portion constituting a first common liquid chamber for supplying a liquid to one liquid flow path; and a plurality of members for generating bubbles in the liquid by applying heat to the liquid. An element substrate on which a heating element is disposed; and a part of a wall of a second liquid passage corresponding to the heating element, which is disposed between the grooved member and the element substrate; A separation member having a movable member displaced toward the first liquid flow path by a pressure based on the generation of the bubble at a position facing the liquid discharge head, wherein the heating element generates the bubble. The part is a bubble generation area, and the heating element is a foaming area related to foaming. The width center of the heating element and the effective foaming area with respect to the flow direction of the liquid are equal, and the condition of the bubble generation area is: effective foaming area ≦ width of bubble generation area ≦ width of heating element. Liquid ejection head. 38. The liquid discharge head according to claim 37, wherein: width of heating element−8 μm ≦ width of bubble generation region. 39. The liquid discharge head according to claim 37, wherein the flow direction of the liquid is a length direction of the heating element and the effective foaming area. A liquid discharge head, wherein length ≦ length of the heating element. 40. The liquid discharge head according to claim 37, wherein the area of the effective foaming area ≦ the area of the movable member, wherein the movable member seals the effective foaming area in a stationary state. Discharge head. 41. The liquid ejection head according to claim 37, wherein a free end of the movable member is located downstream of an area center of the heating element. 42. A first introduction path for introducing a liquid into the first common liquid chamber and a second introduction path for introducing a liquid into the second common liquid chamber, the grooved member. The liquid ejection head according to claim 37, comprising: 43. The liquid discharge head according to claim 42, wherein a plurality of said second introduction paths are provided in said grooved member. 44. The liquid discharge head according to claim 37, wherein a ratio of a sectional area of the first introduction path to a sectional area of the second introduction path is proportional to a supply amount of each liquid. 45. The liquid ejection head according to claim 37, wherein the second introduction path is an introduction path that supplies the liquid to the second common liquid chamber through the separation wall. 46. The liquid discharge head according to claim 15, wherein the liquid supplied to the first liquid flow path and the liquid supplied to the second liquid flow path are the same liquid. 47. The liquid discharge head according to claim 15, wherein the liquid supplied to the first liquid flow path and the liquid supplied to the second liquid flow path are different liquids. 48. The liquid supplied to the second liquid flow path has at least one of low viscosity, foaming property, and heat stability as compared with the liquid supplied to the first liquid flow path. 48. The liquid ejection head according to claim 47, which is an excellent liquid. 49. The liquid discharge head according to claim 7, wherein the heating element is an electrothermal conversion element having a heating resistor that generates heat by receiving an electric signal. 50. The liquid discharge head according to claim 49, wherein the electrothermal transducer has a protective film disposed on the heating resistor. 51. A wiring for transmitting an electric signal to the electrothermal transducer and a functional element for selectively supplying an electric signal to the electrothermal transducer are arranged on the element substrate. 49 liquid ejection heads. 52. The liquid discharge head according to claim 15, wherein the shape of the second liquid flow path in the bubble generation region or the portion where the heating element is arranged is a chamber shape. 53. The liquid discharge head according to claim 15, wherein the shape of the second flow path has a narrowed portion upstream of the bubble generation region or the heating element. 54. The distance from the surface of the heating element to the movable member is 30 μm or less.
The liquid ejection head according to claim 19 or 37. 55. The liquid discharge head according to claim 6, wherein the liquid discharged from the discharge port is ink. 56. A liquid discharge head comprising: the liquid discharge head according to claim 1; and a drive signal supply unit that supplies a drive signal for discharging a liquid from the liquid discharge head. apparatus. 57. A liquid discharge head according to claim 1, further comprising: a recording medium transport unit that transports a recording medium that receives the liquid discharged from the liquid discharge head. Liquid ejection device. 58. Recording is performed by ejecting a recording liquid from the liquid ejection head and attaching the recording liquid to a recording medium including recording paper, cloth, plastic, metal, wood, and leather. Liquid ejection device. 59. The liquid ejecting apparatus according to claim 56, wherein the liquid ejecting head ejects a plurality of colors of recording liquid and causes the plurality of colors of recording liquid to adhere to a recording medium to perform color recording. 60. The liquid ejection apparatus according to claim 56, wherein a plurality of the ejection ports are arranged over the entire width of a recordable area of the recording medium.