JPH1029306A - Liquid discharging method, liquid discharging head, and liquid discharging device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To create a picture quality free from density nonuniformity through constantly stable discharge by a method wherein a liquid temperature in a first liquid flow passage is regulated through a separation wall by regulating a liquid temperature in a second liquid flow passage having a bubble generating area at the time of discharging the liquid. SOLUTION: A sub-heater 2a for regulating temperature, which regulates the temperature of discharging liquid of a first common liquid chamber 15 indirectly through a separation wall 30 by heating a gas-generating liquid, supplied to a second liquid flow passage 16 to a predetermined temperature, is provided on the bottom of a second common liquid chamber 17, i.e., or an element substrate 1. The sub-heater 2a is provided to regulate the temperature of discharging liquid of the whole of a head through small number of heaters and, therefore, it is not necessary to provide the number of pieces of heaters coping with respective flow passage and it is enough that a small number of pieces of the same are arranged in the second common liquid chamber 17. The sub-heater 2a is a temperature regulating means for regulating the temperature of the discharging liquid at a predetermined temperature by heating the liquid to a predetermined temperature and transmit the heat of the foamed liquid to the discharging liquid through the separation wall 30.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid ejecting head for ejecting a desired liquid by generating bubbles caused by applying thermal energy to the liquid, a head cartridge using the liquid ejecting head, a liquid ejecting apparatus, and a liquid ejecting apparatus. The present invention relates to a method for manufacturing a discharge head. Further, the present invention relates to an inkjet kit having these liquid ejection heads.

In particular, the present invention relates to a liquid discharge head having a movable member that is displaced by utilizing the generation of air bubbles, a head cartridge using the liquid discharge head, and a liquid discharge device.

The present invention also relates to a printer, a copying machine, a facsimile having a communication system, and a printer for performing recording on a recording medium such as paper, thread, fiber, cloth, leather, metal, plastic, glass, wood, ceramics and the like. The present invention can be applied to a device such as a word processor having a unit, and further to an industrial recording device combined with various processing devices.

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.

[0005]

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 and the like, a recording apparatus using the bubble jet recording method includes a discharge port for discharging ink, and an ink flow communicating with the discharge port. A passage and an electrothermal converter as an energy generating means for discharging ink arranged in the ink flow path are generally arranged.

According to such a recording method, a high-quality image can be recorded at a 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 printers,
It is used in many office devices such as copiers and facsimile machines, and is increasingly used in industrial systems such as textile printing devices.

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

[0008] 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 which can discharge ink at a high speed and perform good ink discharging 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.

[0010] 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.

In the invention shown in FIGS. 35A and 35B, the valve 1 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. 35 (b), this valve 10
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 by considering the case where bubbles are generated inside the flow path 3 for holding the liquid to be discharged, it is clear that suppressing a part of the back wave by the valve 10 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. .

From such a viewpoint, the liquid (foaming liquid) which generates bubbles by heat and the liquid (ejection liquid) to be ejected are made different liquids, and the ejection liquid is ejected by transmitting the pressure by foaming to the ejection liquid. The method is described in JP-A-61-69467, JP-A-55-81172, U.S. Pat.
No. 80,259 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 ejection liquid and the foaming liquid are completely separated, the pressure at the time of foaming is transmitted to the ejection liquid by expansion and contraction 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.

[0018]

BACKGROUND OF THE INVENTION In the present invention, the fundamental discharge characteristics of the conventional method of discharging air by forming air bubbles (especially air bubbles accompanying film boiling) in the liquid flow path cannot be considered conventionally. From the viewpoint of the above, it is assumed that the level is raised to a level that cannot be predicted conventionally.

This premise returns to the principle of droplet ejection,
Analysis of the principle of the mechanism of the movable member in the flow path in order to provide a new method of discharging droplets using bubbles, which has not been obtained in the past, and a head and the like used in the method. Is obtained by performing a first technical analysis starting from the point of origin, a second technical analysis starting from the principle of droplet ejection by bubbles, and a third analysis starting from the bubble forming region of the heating element for forming bubbles. It was done.

Based on these analyses, the arrangement of 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 area. A completely new technology for actively controlling bubbles by arranging them has been established, and the present applicant has filed an application.

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 also discloses 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. For this reason, some of the present inventors have proposed an extremely 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 heat generating 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 is disclosed that it is also preferable to take into account the above, and that the refill speed can be significantly improved by considering the arrangement of the movable member and the structure of the liquid supply path.

The present inventors have accomplished the present invention with the aim of effectively utilizing the knowledge obtained through such research and the excellent liquid ejection principle from a comprehensive viewpoint.

[0024]

By the way, when printing by the ink jet method, there are a wide variety of fabrics to be dyed, and a wide variety of coloring materials suitable for each fabric. Among them, there are many coloring materials that are hardly soluble or insoluble in water. Usually, a coloring material that is hardly soluble or insoluble in water exists in an emulsified or dispersed form in water. However, if excessive heat is continuously applied to such a water-soluble ink, the emulsified state of the coloring material or the dispersion Are destroyed, and the coloring material is separated from water, and the separated coloring materials may aggregate with each other and become huge. It is also conceivable that clogging of the head is caused by the aggregate of the coloring material.

Also, in printing by the ink jet method, there are problems such as a change in density due to a change in head temperature and a change in a mixing ratio of inks of respective colors, and a change in color appearance. For this reason, Japanese Patent Application Laid-Open No. 7-47692
As indicated by the symbol, it is necessary to maintain the temperature of the printhead in an appropriate range by generating heat from a heater provided in the printhead. When the head is heated by the heat generated by the heater, a method of bringing ink to be ejected directly into the heater in the head and heating the same is effective as a method having good responsiveness. However, even when a small amount of heat is applied to the entire head, a large amount of heat is applied to the ink near the heater. It may be separated from water.

The main objects of the present invention are as follows.

A first object of the present invention is to use a liquid discharge head to which the above-described liquid discharge principle can be applied,
By appropriately adjusting the temperature of the liquid so that the composition and properties of the liquid used in the liquid discharge head do not change or deteriorate due to the heat energy as the discharge energy, it is possible to obtain a stable discharge and an image quality without density unevenness. It is an object of the present invention to provide a liquid ejection head or the like that can perform the above-described operations.

A second object of the present invention is to significantly reduce the amount of heat stored in the liquid on the heating element and to reduce residual bubbles on the heating element while improving the ejection efficiency and ejection force. Another object of the present invention is to provide a liquid discharge method, a liquid discharge head, and the like that can discharge 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 by the back wave and at the same time, by reducing the amount of meniscus retreat by the valve function of the movable member. An object of the present invention is to provide a liquid discharge head or the like 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 discharging method capable of reducing deposits on a heating element and expanding the range of use of a discharging liquid, and having sufficiently high discharging efficiency and discharging power. It is to provide a liquid ejection head and the like.

A fifth object of the present invention is to provide a liquid discharge method, a liquid discharge head, and the like 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 head and an apparatus which are easy to manufacture and inexpensive by configuring a liquid introduction path for supplying a plurality of liquids with a small number of parts.
It is another object of the present invention to provide a liquid discharge head, a device, and the like that are reduced in size.

A seventh object of the present invention is to provide a head kit for facilitating reuse of the liquid discharge head of the present invention.

[0034]

A typical requirement of the present invention to achieve the above object is as follows.

A first liquid flow path communicating with the discharge port, a second liquid flow path having a bubble generation area, and a second liquid flow path disposed between the second liquid flow path and the first liquid flow path. Using a head having a separation wall and a movable member formed on the separation wall and having a free end on the discharge port side and disposed between the first liquid flow path and the bubble generation region; A bubble is generated in the bubble generation region, a free end of the movable member is displaced toward the first liquid flow path based on a pressure generated by the bubble, and the pressure is changed to the first pressure by the displacement of the movable member. When the liquid is discharged by being guided to the discharge port side of the liquid flow path, the temperature of the liquid in the second liquid flow path having the bubble generation region is adjusted to allow the first liquid to flow through the separation wall. A liquid discharge method for adjusting the temperature of the liquid in the liquid flow path.

[0036] In the liquid discharging method, the bubble generation area may include a heating element provided at a position facing the movable member.

The temperature of the liquid in the second liquid flow path is adjusted by:
A liquid discharging method performed by heat generated by the heating element provided in the bubble generation region.

The temperature of the liquid in the second liquid flow path is adjusted by:
A liquid discharging method performed by heat generated by another heating element different from the heating element provided in the bubble generation region.

In another aspect of the present invention, the another heating element is provided in a common liquid chamber communicating with a plurality of the second liquid flow paths.

The heat is applied to the movable member so as to displace the movable member toward the first liquid flow path side and to apply a pressure to the movable member to the extent that the liquid in the first liquid flow path is discharged from the discharge port. Liquid ejection method that does not generate liquid.

The head has a plurality of first liquid flow paths and a plurality of second liquid flow paths individually corresponding to the plurality of first liquid flow paths. A liquid ejection method for adjusting the temperature of a liquid in a liquid flow path for each of the plurality of second liquid flow paths.

The head has a plurality of first liquid flow paths and a plurality of second liquid flow paths individually corresponding to the plurality of first liquid flow paths. A liquid discharging method for adjusting the temperature of the liquid in the liquid flow path to the entirety of the plurality of second liquid flow paths.

The temperature of the liquid in the second liquid flow path is adjusted by:
A liquid discharging method performed by cooling an element substrate provided with the heating element.

A liquid containing a color material emulsified or dispersed in water is supplied to the first liquid flow path, and a liquid not containing the color material is supplied to the second liquid flow path having the bubble generation region. Liquid ejection method.

A liquid discharge method wherein the color material emulsified or dispersed in water is a color material that is insoluble or hardly soluble in water.

A first liquid flow path communicating with the discharge port, a second liquid flow path having a bubble generation region, and a second liquid flow path disposed between the second liquid flow path and the first liquid flow path. And a movable member formed on the separation wall, having a free end on the discharge port side, and disposed between the first liquid flow path and the bubble generation region. A bubble is generated in a generation area, and the free end of the movable member is moved to the first position based on the pressure generated by the bubble.
A liquid discharge head that discharges liquid by displacing the movable member toward the discharge port side of the first liquid flow path by displacing the movable member; A liquid ejecting head having a temperature adjusting means for adjusting the temperature of the liquid in the liquid passage and the liquid in the first liquid flow path via the separation wall.

The liquid discharge head is a heating element provided in the second liquid flow path and different from the heating element forming the bubble generation region.

The liquid discharge head is a cooling means for cooling an element substrate provided with a heating element forming the bubble generation region.

The cooling means includes a coolant supply means for supplying a coolant to at least a part of the element substrate, and a coolant temperature for adjusting the temperature of the coolant supplied by the coolant supply means so as to come into contact with the element substrate. A liquid ejection head including an adjusting unit.

The liquid discharge head, wherein the separation wall is made of a heat transfer material.

A liquid discharge head wherein the heat transfer material is a metal material.

[0052] The liquid discharge head, wherein the another heating element is provided in a common liquid chamber communicating with a plurality of the second liquid flow paths.

A liquid discharge head in which the liquid supplied to the first liquid flow path and the liquid supplied to the second liquid flow path are different liquids.

The liquid supplied to the first liquid flow path is a liquid containing a color material emulsified or dispersed in water, and the liquid supplied to the second liquid flow path is a liquid containing the color material. A liquid ejection head that does not contain liquid.

The liquid discharge head is an electrothermal converter having a heating resistor that generates heat by receiving an electric signal.

[0056] The liquid discharge head, wherein the electrothermal transducer has a protective film disposed on the heating resistor.

A head cartridge having the liquid discharge head and a liquid container for holding a liquid supplied to the liquid discharge head.

[0058] A head cartridge in which the liquid discharge head and the liquid container are separable.

A head cartridge wherein the liquid container is refilled with liquid.

A head cartridge in which the liquid container is provided with a liquid inlet for refilling the liquid.

The liquid ejection head, the first liquid supplied to the first liquid flow path, and the second liquid supplied to the second liquid flow path
And a liquid container for holding the liquid.

[0062] A liquid discharge apparatus comprising: the liquid discharge head; and drive signal supply means for supplying a drive signal for discharging liquid from the liquid discharge head.

A liquid discharge apparatus comprising: the liquid discharge head; and temperature adjusting means for cooling the liquid in the second liquid flow path of the liquid discharge head to adjust the temperature.

A liquid discharge apparatus which discharges the liquid from the discharge port of the liquid discharge head and causes the liquid to adhere to a fabric to perform recording.

[0065] A liquid discharge apparatus, wherein a plurality of discharge ports of the liquid discharge head are arranged over the entire width of a recordable area of a recording medium.

A head kit including the liquid discharge head and a liquid container holding a liquid supplied to the liquid discharge head.

A head kit comprising: the liquid discharge head; a liquid container holding a liquid supplied to the liquid discharge head; and a liquid filling means for filling the liquid container with liquid.

A head kit wherein the liquid is ink for performing recording.

According to the liquid ejection method, 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 bubbles and the movable member displaced by the bubbles, and Since the liquid 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.

Further, according to the present invention, the temperature of the discharged liquid is adjusted via the liquid in the bubble generation region side without directly heating and cooling the discharged liquid, whereby the color material in the discharged liquid can be adjusted. Since separation and the like can be prevented, stable liquid ejection can always be performed, and a good image without density unevenness can be obtained.

According to the characteristic structure of the present invention, it is possible to prevent non-discharge even when the device is left for a long time at a low temperature or low humidity. There is also an advantage that it is possible to immediately return to a normal state by performing a slight recovery process.

More specifically, even under long-term storage conditions in which most of the conventional bubble jet type heads having 64 discharge ports are incapable of discharging, the head of the present invention has about half or less discharge failures. 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 droplets are achieved, and high-speed recording by high-speed liquid ejection and high image quality are achieved. Recording could be enabled.

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 refers to a state in which, when a bubble grows, the bubble does not slip through a gap (slit) around the movable member before the movable member is displaced. Means

Further, the term “separation wall” in the present invention broadly means 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.

[0079]

BEST MODE FOR CARRYING OUT THE INVENTION

(Embodiment 1) Hereinafter, a first embodiment of the present invention will be described in detail with reference to the drawings.

First, in this embodiment, a liquid for discharging
An example in which the discharge force and the discharge efficiency are improved by controlling the direction of pressure propagation based on bubbles and the direction of growth of bubbles will be described.

Here, in the present embodiment, the separation principle will be omitted for the sake of convenience in explaining the ejection principle, and a description will be given using a one-liquid type head in which only movable members are provided.

FIG. 1 is a schematic cross-sectional view of such a liquid discharge head of the present embodiment cut in the liquid flow direction, and FIG. 2 is a partially broken perspective view of the liquid discharge head.

In the liquid discharge head of this embodiment, a heating element 2 (4 in this embodiment) for applying thermal energy to liquid is used as a discharge energy generating element for discharging liquid.
(A heating resistor having a shape of 0 μm × 105 μm)
The liquid flow path 10 is arranged on the element substrate in correspondence with the heating element 2. The liquid flow path 10 has a discharge port 18
And a common liquid chamber 13 for supplying liquid to the plurality of liquid flow paths 10, and receives from the common liquid chamber 13 an amount of liquid corresponding to the liquid discharged from the discharge port. .

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 through the movable member 31 to the discharge port 18 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 heat generating element 2 generates heat to move the movable member 31.
Heat is applied to the liquid in the bubble generation region 11 between the heating element 2 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 of the present invention will be described. One of the most important principles of the present invention is
The movable member disposed to face the bubble is displaced from the first position in the steady state to the second position after the displacement based on the pressure of the bubble or the bubble itself. This is to guide the pressure due to the generation of bubbles and the bubbles themselves 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 VA, and the propagation direction of the pressure toward the upstream side is V
B.

In the conventional head as shown in FIG. 3, there is no structure for regulating the direction of pressure propagation by the generated bubbles 40. Therefore, the pressure propagation direction of the bubble 40 is V1
As shown in V8, the direction was perpendicular to the surface of the bubble, and was oriented in various directions. Among them, those having a component in the pressure propagation direction in the VA direction which has the most influence on the liquid discharge are V1-V
4, ie, a directional component of pressure propagation in a portion closer to the discharge port than a position substantially half of the bubble, and is an important portion directly contributing to liquid discharge efficiency, liquid discharge force, discharge speed, and the like. Further, V1 works efficiently because it is closest to the ejection direction VA, while V4 has relatively little direction component toward VA.

On the other hand, in the case of the present invention shown in FIG. 4, the movable member 31 shifts the pressure propagation directions V1 to V4 of the bubbles, which are oriented in various directions as in the case of FIG. (To the discharge port side) to convert the pressure into the VA pressure 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 in the same manner as the pressure propagation directions V1 to V4, 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 ejection operation of the liquid ejection 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 a part of the liquid filling the bubble generation region 11 is heated by the generated heat, thereby causing 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 bubble 40 has further grown, but the movable member 31 has been further displaced in accordance with the pressure accompanying the bubble 40 generation. 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 a 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, VD1 and VD2 of the flow from the upstream side (B), that is, the common liquid chamber side, in order to supplement the contracted volume of the bubbles in the bubble generation region 11 and to supplement the volume of the discharged liquid. And the liquid flows in from the discharge port side like Vc of the flow.

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

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

After the bubble 40 has reached the maximum volume state and enters the defoaming process after FIG. 1 (c), a volume of liquid that compensates for 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 this embodiment, 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 movable member returns to the original position at the time of defoaming, the meniscus stops retreating, and the liquid supply for the remaining W2 volume is mainly performed by the liquid supply from the flow VD2 of 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 (VD2) 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 refilling was achieved.

The characteristic feature of this embodiment is that when refilling is performed using the pressure at the time of defoaming with a conventional head, the vibration of the meniscus is increased and the image quality is degraded. In the high-speed refill of the above, 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. What you can do.

As described above, the present invention achieves high-speed refilling by forcibly refilling the foaming area via the liquid supply path 12 of the second flow path 16 and suppressing the meniscus retreat and vibration 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 this embodiment will be described below.

In the present embodiment, the second liquid flow path 16 has a liquid supply path 12 having an inner wall which is connected to the heating element 2 substantially flat upstream of the heating element 2 (the surface of the heating element is not greatly reduced).
have. In such a case, the supply of the liquid to the surface of the bubble generation region 11 and the surface of the heating element 2 is performed along the surface of the movable member 31 near the bubble generation region 11 like VD2. Therefore, stagnation of the liquid on the surface of the heating element 2 is suppressed, and deposition of gas dissolved in the liquid and so-called residual air bubbles that cannot be defoamed are easily removed. The heat storage does not become too high. Therefore, more stable generation of bubbles can be repeated at high speed. In the present embodiment, 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. 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 area is performed from the VD1 through the side portion (slit 35) of the movable member. 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 returning to the position of
In the case where the flow resistance of the liquid between the bubble generation region 11 and the region near the discharge port of the first liquid flow path 14 is large, the flow of the liquid from the VD1 to the bubble generation region 11 is prevented. . However, in the head structure of the present invention, the flow VD1 for supplying the liquid to the bubble generation region has a very high liquid supply performance, and the discharge efficiency is such that the movable member 31 covers the bubble generation region 11. Even if a structure requiring improvement is adopted, the liquid supply performance is not reduced.

Incidentally, 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 This is because the free end and the fulcrum 33 are arranged so as not to go against the flows S1, S2, and S3 flowing through the flow path 14 (including the second liquid flow path 16).

Supplementally, in FIG. 1 of this embodiment, as described above, the free end 32 of the movable member 31 has the area center 3 (the heating element 3) that divides the heating element 2 into an upstream area and a downstream area. (A line passing through the center of the area of the liquid flow path and perpendicular to the length direction of the liquid flow path). As a result, the area center position 3 of the heating element
The movable member 31 receives a pressure or a bubble that greatly contributes to the discharge of the liquid generated on the downstream side, and the pressure and the bubble can be guided to the discharge port side, thereby fundamentally improving the discharge efficiency and the discharge force. Can be.

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 makes an instantaneous mechanical displacement is also considered to contribute effectively to the ejection of the liquid.

(Embodiment 2) FIG. 6 shows a second embodiment of the present invention. In FIG. 6, A indicates a state in which the movable member is displaced (bubbles are not shown), B indicates a state in which the movable member is in the initial position (first position), and the state of B indicates a foaming region. It is assumed that 11 is substantially sealed with respect to the discharge port 18. (Here, although not shown, there is a flow path wall between A and B to separate the flow path from the flow path.) The movable member 31 in FIG. Is provided with a liquid supply path 12. This allows
The liquid can be supplied along the surface of the movable member on the heating element side and from a liquid supply path having a surface that is substantially flat or smoothly connected to the surface of the heating element.

Here, at the initial position (first position) of the movable member 31, the movable member 31 is close to or in close contact with the heating element downstream wall 36 and the heating element side wall 37 arranged downstream and laterally of the heating element 2. It is substantially sealed on the discharge port 18 side of the bubble generation region 11. For this reason, the pressure of the bubbles at the time of foaming, particularly the pressure on the downstream side of the bubbles, can be concentrated on the free end side of the movable member without being released.

Further, at the time of defoaming, the movable member 31 returns to the first position, and the liquid is supplied to the heating element at the time of defoaming because the discharge port side of the bubble generation region 31 is substantially closed. It is possible to obtain various effects described in the above embodiment, such as restraint of backward movement. In addition, the same function and effect as in the previous embodiment can be obtained in the effect regarding refill.

In this embodiment, as shown in FIGS. 2 and 6, a base 34 for supporting and fixing the movable member 31 is provided upstream of the heating element 2 and is smaller than the liquid flow path 10. 34, the liquid supply path 12 as described above.
Supply of liquid to Further, the shape of the base 34 is not limited to this, and any shape can be used as long as the refill can be performed smoothly.

In this embodiment, the distance between the movable member 31 and the heating element 2 is set to about 15 μm. However, the distance may be in a range in which the pressure based on the generation of bubbles is sufficiently transmitted to the movable member.

(Embodiment 3) FIG. 7 shows one of the basic concepts of the present invention, and is a third embodiment of the present invention. FIG. 7 shows the bubble generation region in one liquid flow path, and the positional relationship between the bubble generated therein and the movable member.
This is an example in which the liquid ejection method and the refill method of the present invention are more easily understood.

In many of the above-described embodiments, the pressure of generated bubbles is concentrated on the free end of the movable member, and the movement of the bubbles is concentrated on the discharge port side simultaneously with the steep movement of the movable member. Have achieved. On the other hand, in the present embodiment, while giving the degree of freedom of the generated bubble, the downstream portion of the bubble which is the discharge port side of the bubble directly acting on the droplet discharge is regulated by the free end side of the movable member. is there.

In terms of the structure, FIG. 7 is different from FIG. 2 (first embodiment) in that the barrier as the barrier located at the downstream end of the bubble generation area provided on the element substrate 1 in FIG. A convex portion (shaded portion in the figure) is not provided in this embodiment. That is, the free end region and both side end regions of the movable member are opened without substantially closing the bubble generation region with respect to the discharge port region, and this configuration is the present embodiment.

In the present embodiment, since the bubble growth at the downstream end portion of the downstream portion directly acting on the droplet discharge of the bubble is allowed, the pressure component is effectively used for the discharge. In addition, at least the upward pressure (the component force of VB, VB, VB in FIG. 3) of the downstream portion acts so that the free end portion of the movable member is applied to the bubble growth at the downstream end portion. Therefore, the discharge efficiency is improved in the same manner as in the above-described embodiment. In this embodiment, the response to the driving of the heating element is superior to that of the above embodiment.

Further, this embodiment has an advantage in manufacturing because it is simple in structure.

The fulcrum of the movable member 31 of this embodiment is fixed to one base 34 having a small width relative to the surface of the movable member. Therefore, the liquid is supplied to the bubble generation region 11 at the time of defoaming through both sides of the base (see arrows in the figure). This base may have any structure as long as it secures supply.

In the case of this embodiment, the refilling at the time of supplying the liquid is controlled by the presence of the movable member, so that the flow into the bubble generation region from above is controlled by the defoaming of the bubbles. This is excellent for the bubble generation structure of the above. Of course, this can also reduce the amount of meniscus retraction.

As a modification of the third embodiment, it is preferable that only the both ends (one or both sides) of the movable member with respect to the free end be substantially sealed with respect to the bubble generation region 11. Can be According to this configuration, since the pressure directed to the side of the movable member can be changed and used for the growth of the discharge port side end of the bubble described above, the discharge efficiency is further improved.

(Embodiment 4) An embodiment in which the ejection force of the liquid due to the mechanical displacement described above is further improved will be described in this embodiment. FIG. 8 is a cross-sectional view of such a head structure. FIG. 8 shows an embodiment in which the movable member extends so that the position of the free end of the movable member 31 is located further downstream of the heating element. Thereby, the displacement speed of the movable member at the free end position can be increased, and the generation of the ejection force due to the displacement of the movable member can be further improved.

Further, since the free end is closer to the discharge port side than in the previous embodiment, the growth of bubbles can be concentrated on a more stable directional component, so that more excellent discharge can be performed.

The movable member 31 is displaced at a displacement speed R1 in accordance with the bubble growth speed at the center of the pressure of the bubble, and the free end 32 farther from the fulcrum 33 than this position has a higher speed R2. Is displaced. Thereby, the free end 3
2 is applied to the liquid mechanically at a high speed to cause the liquid to move, thereby improving the discharge efficiency.

The free end shape has a shape perpendicular to the liquid flow as in FIG. 7 so that the pressure of the bubbles and the mechanical action of the movable member can be more efficiently contributed to the discharge. Can be.

(Embodiment 5) Hereinafter, an embodiment of a liquid ejection head according to the present invention will be described with reference to the drawings.

In this embodiment, the principle of the main liquid ejection is the same as in the previous embodiment. However, in this embodiment, the liquid flow path is formed into a multi-flow path structure, and the liquid is foamed by further applying heat. The liquid (foaming liquid) and the liquid to be mainly discharged (discharged liquid) can be separated.

FIGS. 9A and 9B are views showing the structure in the liquid flow path of the liquid discharge head of this embodiment.
9A is a schematic cross-sectional view of the liquid discharge head of the present embodiment in the flow channel direction, FIG. 9B is a cross-sectional view taken along the line aa of FIG. 9A, and FIG. FIG. 3 shows a partially broken perspective view of the liquid ejection head.

In the liquid discharge head of this embodiment, a second liquid flow path 16 for foaming is provided on the element substrate 1 on which the heating element 2 for applying thermal energy for generating bubbles in the liquid is provided. The first for the discharge liquid directly communicating with the discharge port 18 above
A liquid flow path 14 is provided. The upstream side of the first liquid flow path 14 communicates with a first common liquid chamber 15 for supplying a discharge liquid to the plurality of first liquid flow paths, and the upstream side of the second liquid flow path 16 has a plurality of And a second common liquid chamber 17 for supplying a foaming liquid to the second liquid flow path. The first common liquid chamber 15 and the second common liquid chamber 17 are separated by a separation wall 30.

In this embodiment, as shown in FIG.
The foaming liquid supplied to the second liquid flow path 16 at the bottom of the second common liquid chamber 17, that is, on the element substrate 1, is heated to a predetermined temperature, and the first common liquid chamber 15 is discharged through the separation wall 30. A sub-heater 2a for adjusting the temperature of the liquid indirectly is provided. The sub-heaters 2a are intended to adjust the temperature of the liquid ejected from the entire head by a small number of heaters. Therefore, it is not necessary to provide the sub-heaters 2a in a number corresponding to each liquid flow path. As shown in FIG. It is sufficient to arrange a small number in the second common liquid chamber 17. The sub-heater 2a can be formed at a predetermined position on the element substrate 1 in the same process as when the heating element 2 for liquid foaming is formed on the element substrate 1 by a known thin film technique.

The sub-heater 2a heats the foaming liquid to a predetermined temperature as described above, and conducts this heat to the discharge liquid through the separation wall 30 to adjust the temperature of the discharge liquid to a predetermined temperature. Temperature adjusting means. In this embodiment, a sub-heater 2a as a temperature adjusting means is provided in addition to the heat generating element 2.
The above-described desired temperature adjustment can be performed. When the temperature of the discharged liquid is adjusted using only the heating element 2, the method is characterized in that the method of adjusting the temperature is different for each liquid flow path. That is, in the liquid flow path (nozzle) for performing liquid discharge, a print signal for generating heat energy sufficient to discharge liquid to the heating element 2 in the nozzle is applied, but the nozzle not performing liquid discharge is used. However, a print signal for generating heat energy that does not reach liquid ejection is added. By adopting such a method, the foaming liquid in the nozzle that does not perform liquid ejection also has a certain rise in temperature. As a result, the calorific value of the foaming liquid becomes uniform to some extent, and the discharged liquid is heated relatively slowly through the separation wall in contact with the foaming liquid. When heat is applied by such gradual heating, the emulsified state or dispersed state of the colorant may be destroyed even if the discharged liquid contains a hardly soluble or insoluble colorant in water. However, when heated rapidly, the emulsified or dispersed state of the coloring material is destroyed, and the coloring material may be separated from water. Then, the coloring material separated from the water gradually aggregates and enlarges, causing clogging of the nozzle and causing non-discharge.

In order to adjust the temperature of the discharged liquid by such a heating element, a cooling system for cooling the foaming liquid may be required. For example, there is a case where a long-time continuous operation is required like ink-jet printing. In a long-time operation, the heating element in the liquid flow path is constantly driven, and the temperature of the foaming liquid in the vicinity of the heating element is also considerably high. This cooling system cools, for example, an element substrate provided with a heating element from the back side, and is configured to supply a coolant from the outside so as to contact the element substrate. This cooling system is roughly composed of temperature adjusting means for adjusting the temperature of the refrigerant, and supply means for supplying the refrigerant, the temperature of which has been adjusted by the temperature adjusting means, to the vicinity of the element substrate. However, the present invention is not limited to this. The details of the means for adjusting the temperature of the discharged liquid will be described later.

However, when the same liquid is used as the foaming liquid and the discharge liquid, the common liquid chamber may be made one and shared.

A separation wall 30 made of a material having elasticity such as metal is provided between the first and second liquid flow paths, and is provided between the first and second liquid flow paths. Are classified. In the case where the foaming liquid and the discharge liquid are liquids that should not be mixed as much as possible, the flow of the liquids in the first liquid flow path 14 and the second liquid flow path 16 can be separated as completely as possible by this separation wall. It is better to perform the separation, but if there is no problem even if the foaming liquid and the discharge liquid are mixed to some extent, the separation wall may not have the function of complete separation.

The separation wall of the portion located in the projection space above the heating element in the plane direction (hereinafter referred to as the discharge pressure generation area; the area A and the bubble generation area 11 in FIG. 9A) is a slit. By 35, the discharge port side (downstream side of the liquid flow) is a free end, and the cantilever-shaped movable member 31 has a fulcrum 33 located on the common liquid chamber (15, 17) side. Since the movable member 31 is disposed so as to face the bubble generation region 11 (B), the movable member 31 operates so as to open toward the discharge port side on the first liquid flow path side by bubbling of the bubbling liquid (arrow in the drawing). direction). FIG.
0, a space forming a second liquid flow path is provided on the element substrate 1 on which the heating resistor as the heating element 2 and the wiring electrode 5 for applying an electric signal to the heating resistor are arranged. The separation wall 30 is arranged via the.

The relationship between the arrangement of the fulcrum 33 and the free end 32 of the movable member 31 and the arrangement with the heating element is the same as in the previous embodiment.

Although the structure of the liquid supply path 12 and the heating element 2 has been described in the previous embodiment, the structure of the second liquid flow path 16 and the heating element 2 is the same in the present embodiment. doing.

Next, the operation of the liquid ejection head of this embodiment will be described with reference to FIG.

In driving the head, the same aqueous ink was used as the discharge liquid supplied to the first liquid flow path 14 and the foaming liquid supplied to the second liquid flow path 16. The heat generated by the heating element 2 acts on the foaming liquid in the bubble generation area of the second liquid flow path, so that the foaming liquid is added to the foaming liquid in the same manner as described in the previous embodiment by U.S. Pat. No. 4,723,129. The bubble 40 is generated based on the film boiling phenomenon as described in the above item.

In this embodiment, there is no escape of the foaming pressure from the three sides except for the upstream side of the bubble generation region, so that the pressure due to the bubble generation is applied to the movable member 6 disposed in the discharge pressure generating section. The movable member 6 is propagated intensively and displaces from the state shown in FIG. 11A to the first liquid flow path side as shown in FIG. 11B with the growth of bubbles. Due to the operation of the movable member, the first liquid flow path 14 and the second liquid flow path 16 communicate with each other largely, and the pressure based on the generation of bubbles mainly occurs in the direction (A direction) on the discharge port side of the first liquid flow path. Convey. The liquid is discharged from the discharge port by the propagation of the pressure and the mechanical displacement of the movable member as described above.

Next, as the bubbles shrink, the movable member 3
1 returns to the position shown in FIG.
In 4, the amount of the discharged liquid corresponding to the amount of the discharged liquid is supplied from the upstream side. Also in this embodiment, since the supply of the discharge liquid is in the direction in which the movable member closes as in the above-described embodiments, the refill of the discharge liquid is not hindered by the movable member.

The present embodiment is the same as the first embodiment and the like in the operation and effect of the main parts relating to the propagation of the foaming pressure due to the displacement of the movable member, the growth direction of the bubbles, the prevention of the back wave, etc. By adopting the two-channel configuration as in the present embodiment, there are further advantages as follows.

That is, according to the configuration of the above embodiment,
The discharge liquid and the foaming liquid are separated from each other, and the discharge liquid can be discharged by the pressure generated by the foaming of the foaming liquid. For this reason, conventionally, even if it is a high-viscosity liquid such as polyethylene glycol, which has been insufficiently foamed even when heat is applied and discharge power is insufficient, this liquid is supplied to the first liquid flow path, Liquid that foams well in the foaming liquid (ethanol: water = 4:
By supplying a liquid having a low boiling point or a liquid having a low boiling point to the second liquid flow path, the liquid can be satisfactorily discharged.

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

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

Further, a liquid weak to heat, for example, a disperse dye,
Even in the case of a liquid in which a metal complex dye, a pigment or the like is dispersed or emulsified in water, this liquid is supplied to the first liquid flow path as a discharge liquid, and is not easily thermally deteriorated in the second liquid flow path. By supplying a liquid that causes foaming, it is possible to discharge with high discharge efficiency and high discharge force as described above without thermally damaging the liquid that is vulnerable to heating.

<Other Embodiments> The embodiments of the main part of the liquid discharge head and the liquid discharge method according to the present invention have been described above. Hereinafter, the embodiments which can be preferably applied to these embodiments will be described with reference to the drawings. It will be described using FIG. However, in the following description, there is a case where either one of the above-described embodiment of the one-flow passage form and the embodiment of the two-flow passage form is described, but it is applicable to both embodiments unless otherwise specified. is there.

<Ceiling Shape of Liquid Flow Path> FIG. 12 is a 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 3 (or the liquid flow path 10 in FIG. 1) is provided on the separation wall 30. In this embodiment, the free end 32 of the movable member
The height of the flow path ceiling near the position 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. 13 is a view for explaining the arrangement relation between the movable member 31 and the second liquid flow path 16 described above. FIG. 2A is a view of the vicinity of the separation wall 30 and the movable member 31 as viewed from above, and FIG. 2B 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 is a diagram schematically showing the arrangement relationship between the movable member 6 and the second liquid flow path 16 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.

In the present embodiment, the second liquid flow path 16 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 foaming liquid in the second liquid flow path provided with the heating element is not so much. Since it can be prevented from being consumed, the bubble generation region 11 of the second liquid flow path
The filling amount of the foaming liquid into the liquid 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. And since this pressure can be used as a discharge force via the movable member 31,
Higher ejection efficiency and ejection 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. 13 (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. In addition, since the escape of bubbles from the slits can be suppressed, the discharge pressure and the discharge efficiency can be further increased. further,
The effect of the refill from the upstream side by the pressure at the time of the defoaming can be enhanced.

In FIGS. 11B and 12,
With the displacement of the movable member 6 toward the first liquid flow path 14, the second
Some of the bubbles generated in the bubble generation region of the liquid flow path 4
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.

<Movable Member and Separation Wall> FIG. 14 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. 13 shows a shape having good operability and durability.
As shown in (a), 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 easily operate without entering the second liquid flow path side. ,
Any shape having excellent durability may be used.

In the above embodiment, the plate-shaped movable member 31
And the separation wall 5 having the movable member is made of nickel having a thickness of 5 μm. However, the material for the movable member and the separation wall is not limited to this, and has a solvent resistance to the foaming liquid and the discharge liquid. Any material may be used as long as it has elasticity to operate well as a movable member and can form a fine slit.

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.

Considering the heat transfer effect of the above-mentioned temperature control means, polyethylene, polypropylene, polyamide, polyethylene terephthalate, melamine resin, phenol resin, epoxy resin, polybutadiene, polyurethane, polyether ether ketone, A resin having good heat resistance, solvent resistance, and moldability represented by recent engineering plastics such as polyether sulfone, polyarylate, polyimide, polysulfone, and liquid crystal polymer (LCP), and a compound thereof, 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 width of the slit 35 for forming the movable member 31 is 2 μm in the present embodiment. However, when the foaming liquid and the discharge liquid are different liquids and it is desired to prevent a mixture of the two liquids, the slit 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 discharge liquid, the liquid mixture can be prevented even with a slit of about 5 μm, but it is preferable that the slit be 3 μm or less. .

The movable member in the present invention has a thickness of the order of μm (t μm), and a movable member having a thickness of 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 (FIGS. 11 and 12, 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 ≦ 1, it was possible to suppress the mixing of the two liquids for a long time.

The slit that gives 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 discharge liquid, the movable member functions as a substantial partition 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 when the viscosity is changed, the mixing of the foaming liquid at the upper limit of 15% is performed. For the foaming liquid of 5 cP or less, the mixing ratio depends on the driving frequency, but it is 10%. % As the upper limit.

In particular, as the viscosity of the discharged liquid is set to 20 cP 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.

By applying energy such as heat to the ink, a state change accompanied by a steep volume change (formation of air bubbles) is caused in the ink, and the ink is ejected from 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. 5, it can be seen that the heating element area and the ink ejection amount are in a proportional relationship, but there is a non-foaming effective region S that does not contribute to ink ejection. 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, in order to effectively use the foaming pressure, it is effective to dispose the movable member so that the movable region of the movable member covers the area just above the effective foaming area about 4 μm or more from the periphery of the heating element. It can be said that it is a target. 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, depending on the type and forming method of the heating element.

FIG. 16 shows that the heating member 2 of 58 × 150 μm has a movable member 301 ((a)
FIG. 2 is a schematic diagram viewed from above when the movable member 302 (FIG. 2B) is arranged.

The dimension 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.

Foaming liquid: 40% aqueous solution of ethanol Discharge ink: dye ink Voltage: 20.2 V Frequency: 3 kHz As a result of an experiment performed under these measurement conditions, regarding the durability of the movable member, (a) the movable member 301 In the case of 1 × 10 ⁷ pulses, the fulcrum of the movable member 301 was damaged when 1 × 10 ⁷ pulses were applied. (B) 3 × 10 ^{8 for the} movable member 302
No damage was seen when the pulse was 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, it can be seen from the viewpoint of both durability and discharge efficiency 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. 17 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. 18 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.

If 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. 19 is a longitudinal sectional view of a liquid discharge head according to the present invention. FIG. 19A shows a head having a protective film described later, and FIG. 19B shows a head without a 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.

A gas 107 such as silicon is provided on the element substrate 1.
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. ) And wiring electrodes (0.2-1.0 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 when bubbles are generated and defoamed are extremely strong, and the durability of a hard and brittle oxide film is significantly reduced.
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 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 protection layer for protecting the resistance layer.

In the present embodiment, a heating element having a heating portion composed of a resistance layer that generates heat in response to an electric signal is used as the heating element. However, the present invention is not limited to this. 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.

Also, 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, the above-described resistance layer 105 is connected to the above-described resistance layer 105 through the wiring electrode 104 as shown in FIG. A rectangular pulse as shown by is applied to cause the resistance layer 105 between the wiring electrodes to generate heat sharply. In the head of each of the above-described embodiments, the heating element is driven by applying a voltage of 24 V, a pulse width of 7 μsec, a current of 150 mA, and an electric signal of 6 kHz, and the liquid ink is discharged from the ejection port by the above-described operation. Discharged. 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> A liquid discharge that 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. 21 is a schematic diagram showing the structure of such a liquid discharge head. The same reference numerals are used for the same components as those 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 (ejection liquid) to each first liquid flow path 3.

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 an 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 the present embodiment, the second liquid supply path 21 is arranged in parallel with the first liquid supply path 20, but is not limited to this, and is arranged outside the first common liquid chamber 15. Any configuration may be used as long as it is formed so as to penetrate through the separated wall 30 and communicate with the second common liquid chamber 17.

The thickness (diameter) of the second liquid supply passage 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 this embodiment shown in FIG. 22, 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 this embodiment, as described above, on the support 70 formed of a metal such as aluminum, an electric heater serving as a heating element for generating heat for generating bubbles due to film boiling of the foaming liquid. An element substrate 1 provided with a plurality of heat 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 the movable member 31 is arranged corresponding 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 the present embodiment, the second supply path for supplying the second liquid to the second liquid flow path and the first supply path for supplying the first liquid to the first liquid flow path Since the road and the grooved top plate as the grooved member are the same, the number of components can be reduced, and the process can be shortened and the cost can be reduced.

Further, 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 movable member as described above can achieve higher ejection force and ejection efficiency than the conventional liquid ejection head. The liquid can be discharged at high speed. In the present embodiment, when the same liquid is used for the foaming liquid and the discharge liquid, the deposit is not easily generated on the heating element by heating without being deteriorated by the heat applied from the heating element, and vaporized by heat. Various liquids can be used as long as they can change the reversible state of condensation and do not deteriorate the liquid flow path, the movable member, the separation wall, and the like.

Of 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 path 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 liquid to be discharged are:
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 recording liquid to be ejected, high-viscosity ink or the like can 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 performed using an ink having the following composition as a recording liquid that can be used for both the discharge liquid and the foaming liquid. Therefore, the landing accuracy of the droplet was improved, and a very good recorded image could be obtained.

Composition of Dye Ink (Viscosity 2 cP) (CI Food Black 2) Dye 3 wt% Diethylene glycol 10 wt% Thiodiglycol 5 wt% Ethanol 5 wt% Water 77 wt% Recording was performed by discharging a combination of liquids having the following compositions. As a result, it was possible to satisfactorily eject a liquid having a viscosity as high as 150 cP as well as a liquid having a viscosity of more than 10 cP, which was difficult to eject with a conventional head, and to obtain a high-quality recorded matter.

Composition of foaming liquid 1 Ethanol 40% by weight Water 60% by weight Composition of foaming liquid 2 Composition of water 100% by weight Composition of foaming liquid 3 Isopropyl alcohol 10% by weight Water 90% by weight Discharge liquid 1 of pigment ink (viscosity of about 15 cP) Composition Carbon black 5% by weight Styrene-acrylic acid-ethyl acrylate copolymer 1% by weight (acid value 140, weight average molecular weight 8000) monoethanolamine 0.25% by weight glycerin 69% by weight thiodiglycol 5% by weight ethanol 3 Weight% water 16.75 weight% composition of ejection liquid 2 (viscosity 55 cP) polyethylene glycol 200 100 wt% composition of ejection liquid 3 (viscosity 150 cP) polyethylene glycol 600 100 wt% Discharge speed is low for the liquid Because, the conducive variation in ejection directionality is poor landing accuracy of the dot on the recording paper, also by variation in the discharge amount due to unstable discharge occurs in these, high-quality image was difficult to obtain. 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.

<Manufacture of Liquid Discharge Head> Next, the process of manufacturing the liquid discharge head of the present invention will be described.

In the case of the liquid discharge head as shown in FIG. 2, a base 34 for providing the movable member 31 on the element substrate 1 is formed by patterning a dry film or the like. 31 was adhered or fixed by welding. Thereafter, a grooved member having a plurality of grooves forming each liquid flow path 10, a discharge port 18, and a concave part forming the common liquid chamber 13 is joined to the element substrate 1 in such a manner that the grooves correspond to the movable members. It was formed by doing.

Next, a description will be given of a manufacturing process of a liquid discharge head having a two-channel configuration as shown in FIGS. 9 and 21.

Generally, the second liquid flow path 1
6, a separation wall 30 is mounted thereon, and a grooved member 50 provided with a groove or the like constituting the first liquid flow path 14 is further mounted thereon. Alternatively, the second liquid flow path 1
After forming the wall of No. 6, the head was manufactured by joining the grooved member 50 on which the separation wall 30 was attached to the wall.

Further, a method of forming the second liquid flow path will be described in detail.

FIGS. 23A to 23E are schematic sectional views for explaining a first embodiment of the method of manufacturing a liquid discharge head according to the present invention.

In this embodiment, as shown in (a), hafnium boride, tantalum nitride and the like are formed on an element substrate (silicon wafer) 1 using the same manufacturing apparatus as used in the semiconductor manufacturing process. After the element for electrothermal conversion having the heating element 2 was formed, the surface of the element substrate 1 was washed for the purpose of improving the adhesion to the photosensitive resin in the next step. Further, in order to improve the adhesiveness, after the surface of the element substrate is surface-modified with ultraviolet-ozone or the like, for example, a silane coupling agent (A189 manufactured by Nippon Yunika)
Is diluted to 1% by weight with ethyl alcohol and spin-coated on the modified surface.

Next, as shown in FIG. 2B, an ultraviolet-sensitive resin film (manufactured by Tokyo Ohka: Dry Film Odile SY) was placed on the substrate 1 having been subjected to surface cleaning and having improved adhesion.
-318) The DF was laminated.

Next, as shown in (c), a photomask PM is arranged on the dry film DF, and ultraviolet rays are passed through the photomask PM to a portion of the dry film DF to be left as the second channel wall. Was irradiated. This exposure step
Manufactured by Canon Inc .: MPA-600, about 6
The exposure was performed at an exposure of 00 mJ / cm ² .

Next, as shown in (d), the dry film DF was developed with a developing solution (BMRC-3, manufactured by Tokyo Ohka Chemical Co., Ltd.) consisting of a mixture of xylene and butyl cellosolve acetate, and the unexposed portion was developed. The portion that was dissolved, exposed and cured was formed as a wall portion of the second liquid flow path 16. Further, the residue remaining on the surface of the element substrate 1 is removed by treating it with an oxygen plasma ashing apparatus (MAS-800, manufactured by Alcantech) for about 90 seconds, and subsequently, at 150 ° C. for 2 hours, and further 100 mJ / cm ^{2 of} ultraviolet irradiation. The exposure was completely cured.

According to the above method, the second liquid flow path can be uniformly formed with high accuracy on a plurality of heater boards (element substrates) which are divided and manufactured from the silicon substrate. A dicing machine (manufactured by Tokyo Seimitsu:
(AWD-4000) to cut and separate each heater board 1. An adhesive (made by Toray:
(SE4400) on the aluminum base plate 70 (FIG. 30). Next, the aluminum base plate 70
An aluminum wire (not shown) having a diameter of 0.05 mm is formed by connecting the printed wiring board 71 bonded above and the heater board 1 to each other.
Connected with.

Next, as shown in FIG. 23 (e), the joined body of the grooved member 50 and the separation wall 30 was positioned and joined to the heater board 1 thus obtained, as shown in FIG. 23 (e).
That is, the grooved member having the separating wall 30 and the heater board 1 are positioned and engaged and fixed by the pressing spring 78, and then the ink / foaming liquid supply member 80 is joined and fixed on the aluminum base plate 70, and the aluminum wire is fixed. , Grooved member 50, heater board 1, and ink / foaming liquid supply member 80
The gap with the silicone sealant (made by Toshiba Silicone:
(TSE399) and completed.

By forming the second liquid flow path by the above-described manufacturing method, it is possible to obtain a high-precision flow path with no positional deviation with respect to the heater of each heater board. In particular, by joining the grooved member 50 and the separation wall 30 in the previous step in advance, the positional accuracy of the first liquid flow path 14 and the movable member 31 can be improved.

[0229] These high-precision manufacturing techniques stabilize ejection and improve print quality. In addition, since it can be formed on a wafer at a time, a large amount can be manufactured at low cost.

In this example, an ultraviolet-curing dry film was used to form the second liquid flow path.
It can also be obtained by using a resin having an absorption band in the ultraviolet region, particularly around 248 nm, curing after laminating, and directly removing the resin in a portion serving as the second liquid flow path with an excimer laser.

FIGS. 24 (a) to 24 (d) are schematic sectional views for explaining a second embodiment of the method of manufacturing a liquid discharge head according to the present invention.

In this embodiment, as shown in (a), a 15 μm-thick resist 10
1 was patterned in the shape of the second liquid flow path.

Next, as shown in FIG.
00 was electroplated to grow a nickel layer 102 on the SUS substrate 100 by 15 μm. As the plating solution, a stress reducing agent (Zerool, manufactured by World Metal Co.), boric acid, a pit preventing agent (NP-APS, manufactured by World Metal Co.), and nickel chloride were used for nickel sulfamate. As for the method of applying an electric field at the time of electrodeposition, an electrode was attached to the anode side, the already patterned SUS substrate 100 was attached to the cathode side, and the temperature of the plating solution was set to 50 ° C.
And the current density was 5 A / cm ² .

Next, as shown in (c), ultrasonic vibration is applied to the SUS substrate 100 which has been plated as described above, and the nickel layer 102 is peeled off from the SUS substrate 100, and the desired second A liquid flow path was obtained.

On the other hand, a heater board provided with an electrothermal conversion element was formed on a silicon wafer using the same manufacturing apparatus as that for semiconductors. This wafer was separated into respective heater boards by a dicing machine in the same manner as in the previous embodiment. The heater board 1 is joined to an aluminum base plate 70 to which a printed board 104 has been joined in advance, and the printed board 7
1 and an aluminum wire (not shown) to form an electrical wiring. On the heater board 1 in such a state, as shown in FIG. 24 (d), it was positioned and fixed to the second liquid flow path obtained in the previous step. At the time of this fixing, as in the first embodiment, since the top plate on which the separation wall is fixed is engaged with and tightly attached to the top plate by the pressing spring in the subsequent step, it is fixed to the extent that no positional displacement occurs at the time of joining the top plate. Is enough.

In this embodiment, an ultraviolet curing adhesive (Amicon UV-3 manufactured by Grace Japan) is used for the positioning and fixing.
00), and using an ultraviolet irradiation device, the exposure amount is 10
Fixation was completed in about 3 seconds at 0 mJ / cm ² .

According to the manufacturing method of this embodiment, it is possible to obtain the second liquid flow path with high accuracy without displacement with respect to the heating element, and since the flow path wall is formed of nickel, It is possible to provide a highly reliable head that is resistant to alkaline liquids.

FIGS. 25A to 25D are schematic sectional views for explaining a third embodiment of the method for manufacturing a liquid discharge head according to the present invention.

In this embodiment, as shown in FIG. 15A, a resist 31 was applied to both surfaces of a 15 μm thick SUS substrate 100 having alignment holes or marks 100a. Here, as the resist, P made by Tokyo Ohka
MERP-AR900 was used.

After that, as shown in FIG.
Exposure was performed using an exposure apparatus (MPA-600, manufactured by Canon Inc.) in accordance with the alignment hole 100a of No. 00, and the resist 103 in the portion where the second liquid flow path was to be formed was removed. The exposure was performed at an exposure amount of 800 mJ / cm ² . Next, as shown in FIG.
The SUS substrate 100 patterned with No. 3 was immersed in an etchant (an aqueous solution of ferric chloride or cupric chloride) to etch a portion exposed from the resist 103, and then the resist was peeled.

Next, as shown in (d), the etched SUS substrate 100 is positioned and fixed on the heater board 1 and the second liquid flow path 4 is formed in the same manner as in the above embodiment of the manufacturing method. Was assembled.

According to the manufacturing method of this embodiment, the second liquid flow path 4 can be obtained with high accuracy without any positional deviation with respect to the heater. In addition, since the flow path is formed of SUS, acid or alkaline And a highly reliable liquid ejection head can be provided.

As described above, according to the manufacturing method of this embodiment, the electrothermal transducer and the second liquid flow path are formed by disposing the walls of the second liquid flow path in advance on the element substrate. Positioning can be performed with high accuracy. In addition, since the second liquid flow path can be formed simultaneously on a large number of element substrates on the substrate before cutting and separation, a large amount of low-cost liquid discharge head can be provided.

The liquid discharge head obtained by performing the method of manufacturing a liquid discharge head of the present embodiment is as follows.
Since the heating element and the second liquid flow path are positioned with high precision, the pressure of foaming due to the heat generated by the electrothermal transducer can be efficiently received, and the discharge efficiency is excellent.

Here, an embodiment of the means for adjusting the temperature of the discharged liquid in the liquid discharge head of this embodiment will be described with reference to the drawings.

(Embodiment 1 of Temperature Control Means)
As shown in (a) and (b), a configuration in which a sub-heater for temperature adjustment is provided in the common liquid chamber on the foaming liquid side is a temperature adjusting means for the entire liquid ejection head with respect to the ejection liquid.

In this embodiment, a first common liquid chamber 15 for supplying ink (discharge liquid) to a plurality of first liquid flow paths 14 having discharge ports 18 for discharging ink to a print medium is provided.
And a second common liquid chamber 17 for supplying a clear ink (foaming liquid) containing no coloring material to a plurality of second liquid flow paths 16 communicating with the first liquid flow path 14 and a valve (movable member) 31. Is a liquid ejection head having a configuration having: In this configuration, the ink in the first common liquid chamber 15 can be heated by heating the foaming liquid filled in the second common liquid chamber 17.

The second common liquid chamber 17 is provided with a sub-heater 2a, and generates heat by applying a pulse-like drive voltage. The sub-heater 2a heats the ink in advance so that the temperature rise in the nozzle goes smoothly. The drive pulse is applied to the sub-heater 2a when the temperature measured by a sensor (not shown) in the head is equal to or lower than the set head temperature of 40 ° C. The amount of heat generated by the application of the pulse heats the liquid to about 200 ° C. in a portion in contact with the heater, but a portion not in contact with the heater receives heat slowly from the portion in contact with the heater. Then, the ink in the liquid chamber communicating with each nozzle via the separation wall 30 is heated by the amount of heat from the liquid thus heated.

In a so-called two-liquid type liquid discharge head that performs liquid discharge using two different types of liquids as described above,
Heat on the foaming liquid side is transmitted to the discharging liquid side through a separation wall that separates the foaming liquid and the discharging liquid. Therefore, the discharge liquid (ink)
However, since excessive heat is not locally applied, the ink can be heated to an appropriate temperature, and the image quality can be further improved without density unevenness even when the power is turned on by smooth heating in the nozzles.

In particular, even if the ink contains a coloring material that is hardly soluble or insoluble in water, and the coloring material is present in an emulsified or dispersed state, it does not cause destruction of the emulsified or dispersed state due to excessive heat and is stable. To heat the ink. As a result, stable ejection without clogging becomes possible.

Here, the sub heater 2a is set at 50
A drive voltage of 24 V and a heat quantity of 100 μs are given at a period of 0 μs.

(Embodiment 2 of Temperature Adjusting Means) FIG. 26 (a)
2A and 2B are waveform diagrams of signals applied to a heating element for liquid ejection in temperature adjustment in the present embodiment, and FIG.
FIG. 7 is a cross-sectional view for explaining the temperature distribution in the liquid flow path in which the liquid is not discharged, and FIG. 28 is a graph showing the temperature change of each part shown in FIG. 27 when the pulse application timing is plotted on the horizontal axis. It is.

The temperature adjusting means in this embodiment is not provided with the sub-heater dedicated to the temperature adjustment in the first embodiment, but uses the heating element 2 for discharging liquid to adjust the temperature for each liquid flow path (nozzle). Is what you do. That is, as described above, in the liquid flow path (nozzle) for performing liquid discharge, a discharge signal for generating heat energy sufficient to discharge the liquid to the heating element 2 in the nozzle (see FIG. ) Is added, but a non-ejection signal (see FIG. 26 (b)) for generating heat energy that does not lead to liquid ejection even in a nozzle that does not eject liquid is added.

By adopting such a method, the temperature of the foaming liquid in the nozzle that does not perform liquid ejection also rises to some extent. As a result, as shown in FIG. 28, the temperature (part B) of the foaming liquid becomes uniform to some extent, and the discharge liquid (C) passes through the separation wall in contact with the foaming liquid.
Part) is also heated relatively slowly. When heat is applied by such gradual heating, even if the ejection liquid contains a coloring material that is hardly soluble or insoluble in water, the emulsified or dispersed state of the coloring material is not destroyed. There is an advantage that an image without density unevenness can always be printed with stable ejection.

FIGS. 27 and 28 show the temperatures of the vicinity of the heater at the non-ejection nozzle (A), the clear ink (B) of the entire second liquid flow path, and the ink (C) of the first liquid flow path. Is shown. Here, for the heater of the non-ejection nozzle, a driving voltage of 24 V and a heat quantity of 1.3 μs are applied to the heater of the non-ejection nozzle for 176 hours.
It is given at a period of μs.

(Third Embodiment of Temperature Adjusting Means) FIG.
5A and 5B show the configuration of the liquid discharge head of this embodiment, FIG. 5A is a schematic sectional view showing the structure of a liquid flow path of the head, and FIG. It is a graph which shows a temperature distribution.

This embodiment is characterized in that, in addition to the first and second embodiments, a cooling means for cooling the element substrate itself provided with a temperature adjusting means such as a heater is provided. This cooling means 2
b denotes a cooling path 2c that contacts the back surface of the element substrate 1, and a refrigerant temperature adjusting means 2 that adjusts the temperature of the refrigerant in the cooling path 2c.
d, and supply means 2e for supplying the coolant, the temperature of which has been adjusted by the adjusting means 2d, to the cooling path 2c. Since the element substrate 1 is cooled to a predetermined temperature by the cooling means 2b, the second liquid flow path 16 flowing in contact with the element substrate 1 and the second common flow for supplying the foaming liquid to the second liquid flow path 16 The foaming liquid in the liquid chamber 17 can be efficiently cooled to a predetermined temperature. Therefore, even when driving for a long time as in ink-jet printing, it is possible to suppress a rise in the temperature of the foaming liquid and the discharge liquid. In addition, as a refrigerant | coolant, water can be mentioned, for example.

The liquid discharge head shown in FIG.
This is a recording head held by a thermal recording head unit. This multi-nozzle head is formed with thousands to thousands of nozzles arranged along the front and back directions of the paper surface of FIG. 29A, and FIG. 29 is a cross section of one of the nozzles. From the second common liquid chamber 17 which is a common liquid chamber for clear ink (foaming liquid side), the clear ink filled in the second liquid flow path 16 which is an individual liquid chamber for each nozzle is discharged by applying a pulse voltage. The ink (discharge liquid side) in the first liquid flow path 14 is turned into ink droplets by the bubbles in the clear ink which is instantaneously heated by the heater 2 and generated by the heat energy thereof, and is applied to the cloth A as a printing material. Discharged. The discharge heater 2 is formed on the surface of a base plate (element substrate) 1. The back of the base plate 1 (in FIG. 29,
On the lower side), a water jacket 2c as a cooling path is attached. The water jacket 2c removes heat from the back surface of the base plate 1 with the cooling water, and the cooling water is adjusted to a predetermined temperature by the water temperature controller 2d, and then the head 2 is again rotated at a constant speed by the pump 2e as a coolant supply means. It is returned to the water jacket 2c.

FIG. 29 (b) shows the temperature distribution of the nozzle portion during printing with the above-mentioned applied pulse. The vertical direction in the figure corresponds to between the nozzle and the cooling water. The left-right direction in the figure is a temperature axis, and Tw indicates the temperature of the cooling water. The print head is cooled at a fixed rate by the cooling water, and is set so that the heat value of the print head is constant during the printing operation regardless of the ejection of ink droplets from the nozzles as described above. Therefore, in the base plate, the temperature difference ΔT between the nozzle side and the cooling water side is always constant irrespective of the printing duty and the history of the printing operation. Therefore, the temperature (nozzle temperature) near the heater filled with the clear ink can be reliably contained within the extremely narrow target temperature range T1 by appropriately setting the temperature of the cooling water. Further, since the temperature of the ink is controlled via the clear ink having a small temperature change, the temperature change is suppressed to a narrower target temperature range T0.

In such a two-liquid type liquid ejection head, by providing cooling means on the liquid chamber side filled with ink containing no coloring material, the temperature change of the ink in the nozzles can be further reduced. Even with a long head with a large temperature rise, smooth image quality with less density unevenness
It can be always obtained even with an ink composed of a coloring material (dispersed dye, pigment, etc.) that is hardly soluble or insoluble in water.

Next, the ink used in this embodiment will be described. Inks suitable for this embodiment include water-insoluble,
Alternatively, an ink-jet ink in which a hardly soluble colorant is dispersed can be used. A colorant is a substance having a property of giving a color to an object. Here, disperse dyes, metal complex dyes, pigments and the like are used.

As the disperse dye, C.I. I. Disperse Yellow 5, 42, 54, 64, 79, 82, 83, 9
3, 99, 100, 119, 122, 124, 126,
160, 184: 1, 186, 198, 199, 20
4, 211, 224 and 237; I. Disperse Orange 13, 29, 31: 1, 33, 49, 54,
55, 66, 73, 118, 119 and 163;
I. Disperse Red 54, 72, 73, 86, 8
8, 91, 92, 93, 111, 126, 127, 13
4, 135, 143, 145, 152, 153, 15
4, 159, 164,: 1,177,181,204,
206, 207, 221, 239, 240, 258, 2
77, 278, 283, 288, 311, 323, 34
3, 348, 356 and 362; I. Disperse Violet 33, I.P. C. Disperse Blue 5
6, 60, 73, 79, 79: 1, 87, 87: 1, 1
13, 128, 143, 148, 154, 158, 16
5, 165: 1, 165: 2, 176, 183, 18
5, 197, 198, 201, 214, 224, 22
5, 257, 266, 267, 287, 354, 35
8, 365 and 368; I. Disperse Greens 6: 1 and 9 are preferred, but not limited to these dyes.

Further, the content of these dyes (total content when two or more dyes are used in combination) is 0.1 to 25% by weight, preferably 0.5 to 20% by weight, and more preferably 1 to 25% by weight. -15% by weight. When the content of the disperse dye is 0.
If the amount is less than 1% by weight, the color density is insufficient. When the content exceeds 25% by weight, the storage stability of the ink is deteriorated, and the ink is likely to be thickened or deposited due to the evaporation of the ink in the vicinity of the nozzle tip, causing non-discharge.

Further, as the compound for dispersing the disperse dye in the aqueous medium of the ink used in the present invention, a so-called dispersant, surfactant, resin and the like can be used. As the dispersant or the surfactant, any of anionic and nonionic can be used. Examples of the anionic one include a fatty acid salt, an alkyl sulfate salt, an alkyl benzene sulfonate, an alkyl naphthalene sulfonate and a dialkyl sulfo succinate. Acid salts, alkyl phosphate salts, naphthalene sulfonic acid formalin condensates, polyoxyethylene alkyl sulfate salts, and substituted derivatives thereof, and the like. Nonionic ones include polyoxyethylene alkyl ether, polyoxyethylene alkyl Phenyl ether, polyoxyethylene fatty acid ester, sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene alkylamine, glycerin fatty acid ester, oxyethyleneoxy Pyrene block polymers, and substituted derivatives thereof.

Examples of the resin dispersant include styrene and its derivatives, vinyl naphthalene and its derivatives, aliphatic alcohol esters of α, β-unsaturated carboxylic acids, acrylic acid and its derivatives, maleic acid and its derivatives,
At least two or more monomers obtained from itaconic acid and its derivatives, fumaric acid and its derivatives, vinyl acetate, vinyl alcohol, vinylpyrrolidone, acrylamide, and its derivatives (at least one of which is a hydrophilic monomer) Block copolymer, random copolymer and graft copolymer, and salts thereof. These resins are preferably alkali-soluble resins that are soluble in an aqueous solution in which a base is dissolved.

The ink used in the present invention contains water as a main component and is contained in an amount of 10 to 93% by weight, preferably 25 to 87% by weight, more preferably 30 to 82% by weight based on the total weight of the ink. Is preferred. Further, by using a water-soluble organic solvent, the effect of the present invention can be made more remarkable. Examples of such solvents include monohydric alcohols such as methanol, ethanol, and isopropyl alcohol; ketones and keto alcohols such as acetone and diacetone alcohol; ethers such as tetrahydrofuran and dioxane; diethylene glycol, triethylene glycol, and tetraethylene glycol. Oxyethylene or oxypropylene addition polymers such as ethylene glycol, dipropylene glycol, tripropylene glycol, polyethylene glycol, and polypropylene glycol; ethylene glycol, propylene glycol,
Alkylene glycols having an alkylene group containing 2 to 6 carbon atoms, such as trimethylene glycol, butylene glycol and hexylene glycol; triols such as 1,2,6-hexanetriol; thiodiglycol; bishydroxyethyl sulfone; Glycerin; lower alkyl ethers of polyhydric alcohols such as ethylene glycol monomethyl (or ethyl) ether, diethylene glycol monomethyl (or ethyl) ether, and triethylene glycol monomethyl (or ethyl) ether; triethylene glycol dimethyl (or ethyl) ether, tetraethylene glycol Lower dialkyl ethers of polyhydric alcohols such as ethylene glycol dimethyl (or ethyl) ether; sulfolane, N-methyl-2-pyrrolidone,
-Pyrrolidone, 1,3-dimethyl-2-imidazolidinone and the like. The content of the water-soluble organic solvent,
Generally, 0 to 50% by weight based on the total weight of the ink.
%, Preferably in the range of 2-45%.

When the above medium is used in combination, it can be used alone or as a mixture. The most preferable liquid medium composition is one in which the solvent contains at least one kind of monohydric or polyhydric alcohol and a derivative thereof. . Among them, thiodiglycol, bishydroxyethyl sulfone, diethylene glycol, triethylene glycol, triethylene glycol monomethyl ether, tetraethylene glycol dimethyl ether, and ethanol are particularly preferable.

The main components of the ink used in the printing method of the present invention are as described above, but other various dispersants, surfactants, viscosity modifiers, surface tension modifiers, fluorescent brighteners and the like are required. It can be added according to.

As the metal complex salt dyes, Acid Milling Yellow MR, Acid Milling Cyanine 5R,
Acid First Cyanin Green G, Acid Milling Black TLB, Acid Blue Black 10
B, metallized yellow G, metallized brilliant blue G, metallized brown RR, metallized black BGL, and metallized black GL are preferred, but are not limited to these dyes.

Examples of the pigment include inorganic pigments such as ultramarine, titanium oxide, and tenal blue, as well as diazo yellow, disazo orange, and permanent carmine F.
B, phthalocyanine blue, phthalocyanine green,
Organic pigments such as thioindigo violet and dioxazine violet are not limited to these pigments.

<Liquid Discharge Head Cartridge> Next, a liquid discharge head cartridge equipped with the liquid discharge head according to the above embodiment will be schematically described.

FIG. 30 is a schematic exploded perspective view of a liquid discharge head cartridge including the above-described liquid discharge head. The liquid discharge head cartridge is mainly composed of a liquid discharge head section 200 and a liquid container 80. I have.

The liquid discharge head unit 200 includes the element substrate 1,
It comprises a separation wall 30, a grooved member 50, a pressing spring 78, a liquid supply member 90, a support 70 and the like. As described above, the element substrate 1 is provided with a plurality of heating resistors for applying heat to the foaming liquid in a row, and a functional element for selectively driving the heating resistors. Are provided. This element substrate 1 and the aforementioned separation wall 3 having a movable wall
0, a foaming liquid passage is formed, and the foaming liquid flows. By joining the separation wall 30 and the grooved top plate 50, a discharge flow path (not shown) through which the discharged liquid to be discharged flows is formed.

The pressing spring 78 is a member for applying an urging force in the direction of the element substrate 1 to the grooved member 50. With this urging force, the element substrate 1, the separating wall 30, the grooved member 50, and a support member to be described later are used. 70 and satisfactorily integrated.

The support 70 supports the element substrate 1 and the like. On the support 70, a circuit board 71 for connecting to the element substrate 1 and supplying an electric signal,
A contact pad 72 for exchanging electrical signals with the device by connecting to the device is provided.

The liquid container 90 contains therein a discharge liquid such as ink and a foaming liquid for generating bubbles, which are supplied to the liquid discharge head. Outside the liquid container 90, a positioning portion 94 for arranging a connection member for connecting the liquid ejection head and the liquid container and a fixed shaft 95 for fixing the connection portion are provided. The discharge liquid is supplied from the discharge liquid supply path 92 of the liquid container to the discharge liquid supply path 81 of the liquid supply member 80 via the supply path 84 of the connection member.
And the discharge liquid supply paths 83, 71, 21 of each member
To the first common liquid chamber. Similarly, the foaming liquid is supplied from the supply path 93 of the liquid container to the foaming liquid supply path 82 of the liquid supply member 80 via the supply path of the connecting member, and is supplied via the foaming liquid supply paths 84, 71, and 22 of the respective members. The liquid is supplied to the second liquid chamber.

In the above-described liquid discharge head cartridge, the supply form and the liquid container capable of supplying the liquid are described also when the foaming liquid and the discharge liquid are different liquids. However, when the discharge liquid and the foam liquid are the same. However, the supply path and the container for the foaming liquid and the discharge liquid do not have to be divided.

It is to be noted that the liquid container may be refilled and used after consumption of each liquid. For this purpose, it is desirable to provide a liquid inlet in the liquid container. Further, the liquid discharge head and the liquid container may be integrated or may be separable.

<Liquid Discharge Apparatus> FIG. 31 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.

In the liquid discharge apparatus of this embodiment, the motor 111 as a drive source for driving the recording medium transport 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. 32 is a block diagram of the entire apparatus for operating ink discharge recording to which the liquid discharge method and the 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 paper, the CPU 302 generates drive data for driving a driving motor for moving the recording paper 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 above-described recording apparatus and to which a liquid such as ink is applied includes plastics, cloth, aluminum, etc. 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 the discharge liquid used in these liquid discharge devices, a liquid suitable for each recording medium and recording conditions may be used.

<Recording System> Next, an example of an ink jet recording system in which recording is performed on a recording medium using the liquid discharge head of the present invention as a recording head will be described.

FIG. 33 is a schematic diagram for explaining the configuration of an ink jet recording system using the above-described liquid discharge head 201 of the present invention. The liquid ejection head in this embodiment is a full line type head in which a plurality of ejection ports are arranged at intervals of 360 dpi in a length corresponding to the recordable width of the recording medium 150, and is yellow (Y), magenta (M). , Cyan (C), and black (Bk) are fixedly supported in parallel by a holder 202 at predetermined intervals in the X direction.

A signal is supplied to each of these heads from a head driver 307 constituting drive signal supply means, and each head is driven based on this signal.

In each head, Y, M, C,
Bk four color inks are supplied from ink containers 204a to 204d, respectively. Reference numeral 204e denotes a foaming liquid container in which a foaming liquid is stored, and the foaming liquid is supplied from the container to each head.

[0292] Below each head, a head cap 203 having an ink absorbing member such as a sponge disposed therein.
a to 203d are provided, and the maintenance of the head can be performed by covering the ejection openings of each head during non-printing.

Reference numeral 206 denotes a transport belt which constitutes a transport means for transporting various non-recording media as described in each of the above embodiments. The transport belt 206 is drawn around a predetermined path by various rollers, and is driven by a driving roller connected to a motor driver 305.

In the ink jet recording system of this embodiment, a pre-processing device 251 and a post-processing device 252 for performing various processes on a recording medium before and after recording are respectively arranged upstream and downstream of the recording medium transport path. Provided.

The contents of the pre-processing and post-processing differ depending on the type of recording medium on which recording is performed and the type of ink. For example, for a recording medium such as metal, plastic, and ceramics, As a pretreatment, irradiation of ultraviolet rays and ozone is performed to activate the surface, thereby improving the adhesion of the ink. Further, in a recording medium such as plastic which easily generates static electricity, dust easily adheres to the surface due to the static electricity, and good recording may be hindered by the dust. For this reason, it is preferable to remove dust from the recording medium by removing static electricity from the recording medium using an ionizer device as a pretreatment.
When a cloth is used as a recording medium, an alkaline substance,
A treatment for providing a substance selected from a water-soluble substance, a synthetic polymer, a water-soluble metal salt, urea, and thiourea may be performed as pretreatment. The pre-processing is not limited to these, and may be a process of setting the temperature of the recording medium to a temperature suitable for recording.

On the other hand, the post-processing includes a fixing process for promoting the fixing of the ink to the recording medium to which the ink has been applied by heat treatment, ultraviolet irradiation, or the like, or a cleaning process for applying the pre-treatment and remaining unreacted processing agent. And the like.

Although the present embodiment has been described using a full-line head as a head, the present invention is not limited to this. For example, a small-sized head as described above is conveyed in the width direction of a recording medium to perform recording. It may be something.

<Head Kit> A head kit having the liquid ejection head of the present invention will be described below. FIG.
FIG. 2 is a schematic view showing such a head kit. The head kit includes a head 510 of the present invention having an ink ejection unit 511 for ejecting ink, and an ink container 520 which is an inseparable or separable liquid container from the head. When,
An ink filling means holding the ink for filling the ink container with ink is contained in a kit container 501.

When the ink has been consumed, the insertion portion of the ink filling means (such as an injection needle or the like) is inserted into the air communication port 521 of the ink container, the connection portion with the head, or a hole formed in the wall of the ink container. It is sufficient to insert a part of 531 and fill the ink container with the ink in the ink filling means through the insertion portion.

As described above, the liquid discharge head of the present invention,
By packing the ink container and ink filling means into one kit container to make a kit, even if the ink is consumed, the ink can be quickly and easily filled into the ink container as described above. Recording can be started quickly.

Although the head kit of this embodiment has been described as including the ink filling means, the head kit does not have the ink filling means, and is a separable type ink container filled with ink. The head and the head may be housed in a kit container 510.

In FIG. 34, only the ink filling means for filling the ink container with ink is shown, but in addition to the ink container, a foaming liquid filling means for filling the foaming liquid container with the foaming liquid is provided. It may be in a form contained in a kit container.

[0303]

As described above, according to the present invention,
A liquid ejection head that can apply the new liquid ejection principle is used, and the temperature of the liquid is appropriately adjusted so that the composition and properties of the liquid used in the head do not change or deteriorate due to heat energy as ejection energy. By doing so, it is possible to always obtain stable image quality with stable ejection without density unevenness.

According to the liquid ejection method, the head, and the like of the present invention based on the above-described novel ejection principle using the movable member, a synergistic effect between the generated bubble and the movable member displaced by the bubble can be obtained. 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 discharge method, head, and the like.

Further, according to the characteristic structure of the present invention, it is possible to prevent non-ejection even when the apparatus is left for a long time at a low temperature or low humidity. There is also an advantage that it is possible to immediately return to a normal state by performing a slight recovery process such as recovery. Along with this, the recovery time can be shortened, the loss of liquid due to the 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 droplets are achieved, and high-speed recording by high-speed liquid ejection and high image quality are achieved. Recording could be enabled.

Further, by using a liquid which is easily foamed or a liquid which does not easily generate deposits (burns) on the heating element as the foaming liquid in the head having the two flow paths, the degree of freedom in selecting the discharge liquid is increased. Liquids that were difficult to be discharged by the conventional bubble jet discharge method, such as high-viscosity liquids that became high and hardly foamed, and liquids that easily formed a volume on the heating element, could be discharged well.

Further, a liquid or the like which is weak to heat could be ejected without adversely affecting the liquid by heat.

Further, according to the method of manufacturing a liquid discharge head of the present invention, the above-described liquid discharge head can be manufactured with high accuracy, and the number of parts can be reduced, and it can be manufactured easily at low cost.

Further, by using the liquid discharge head of the present invention as a liquid discharge recording head for recording, it was possible to achieve higher quality recording.

Further, it was possible to provide a liquid discharge apparatus, a recording system, and the like in which the liquid discharge efficiency and the like of the liquid were further improved by using the liquid discharge head of the present invention.

Further, by using the head cartridge or the head kit of the present invention, the head can be easily used and reused.

[Brief description of the drawings]

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

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

FIG. 5 is a schematic diagram for explaining a flow of a liquid according to the present invention.

FIG. 6 is a partially cutaway perspective view of a liquid ejection head according to a second embodiment of the present invention.

FIG. 7 is a partially broken perspective view of a liquid ejection head according to a third embodiment of the present invention.

FIG. 8 is a sectional view of a liquid ejection head according to a fourth embodiment of the present invention.

FIGS. 9A and 9B are cross-sectional views of a liquid ejection head (two flow paths) according to a fifth embodiment of the present invention.

FIG. 10 is a partially broken perspective view of a liquid ejection head according to a sixth embodiment of the present invention.

FIG. 11 is a diagram for explaining the operation of the movable member.

FIG. 12 is a view for explaining a structure of a movable member and a first liquid flow path.

FIG. 13 is a view for explaining a structure of a movable member and a liquid flow path.

FIG. 14 is a view for explaining another shape of the movable member.

FIG. 15 is a diagram illustrating a relationship between a heating element area and an ink ejection amount.

FIG. 16 is a diagram showing an arrangement relationship between a movable member and a heating element.

FIG. 17 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. 18 is a diagram for explaining an arrangement relationship between a heating element and a movable member.

FIG. 19 is a longitudinal sectional view of the liquid ejection head of the present invention.

FIG. 20 is a schematic diagram showing a shape of a driving pulse.

FIG. 21 is a cross-sectional view for explaining a supply path of the liquid ejection head of the present invention.

FIG. 22 is an exploded perspective view of a head according to the present invention.

FIG. 23 is a process chart for describing the method for manufacturing a liquid discharge head according to the present invention.

FIG. 24 is a process chart for explaining the method for manufacturing a liquid discharge head according to the present invention.

FIG. 25 is a process diagram for describing the method for manufacturing a liquid discharge head according to the present invention.

FIGS. 26A and 26B are waveform diagrams of signals applied to a heating element for liquid ejection in temperature adjustment in the liquid ejection head of the present invention.

FIG. 27 is a cross-sectional view for explaining a temperature distribution in a liquid flow path in which liquid is not discharged.

FIG. 28 is a graph showing a temperature change of each part shown in FIG. 28 when the pulse application timing is plotted on the horizontal axis.

29 (a) and (b) show a configuration of a liquid ejection head of the present invention, where (a) is a schematic cross-sectional view showing the structure of a liquid flow path of the head, and (b) is (a) 4 is a graph showing a temperature distribution of the liquid flow path of FIG.

FIG. 30 is an exploded perspective view of the liquid ejection head cartridge.

FIG. 31 is a schematic configuration diagram of a liquid ejection device.

FIG. 32 is a device block diagram.

FIG. 33 is a diagram illustrating a liquid ejection recording system.

FIG. 34 is a schematic diagram of a head kit.

FIG. 35 is a view for explaining a liquid flow path structure of a conventional liquid discharge head.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Element board 2 Heating element (temperature adjusting means) 2a Sub heater (temperature adjusting means) 2b Cooling means (temperature adjusting means) 3 Center of area 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 second liquid flow path 17 second common liquid chamber 18 discharge port 19 constricted 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 fulcrum 34 support member 35 slit 36 bubble generation region front wall 37 bubble generation region side wall 40 bubble 45 droplet 50 grooved member 51 orifice plate 70 support 78 spring 80 supply member

Claims (34)

[Claims] 1. A first liquid flow path communicating with a discharge port, a second liquid flow path having a bubble generation region, and a first liquid flow path between the second liquid flow path and the first liquid flow path. A head having a separation wall disposed therein, and a movable member formed on the separation wall and having a free end on the discharge port side and disposed between the first liquid flow path and the bubble generation region. Generating bubbles in the bubble generation region, displacing a free end of the movable member to the first liquid flow path side based on a pressure caused by the generation of the bubbles, and displacing the pressure by the displacement of the movable member; When the liquid is discharged by guiding the liquid to the discharge port side of the first liquid flow path, the temperature of the liquid in the second liquid flow path having the bubble generation region is adjusted to allow the liquid to flow through the separation wall. A liquid discharging method comprising: adjusting a temperature of a liquid in a first liquid flow path. 2. The liquid discharging method according to claim 1, wherein the bubble generation region has a heating element provided at a position facing the movable member. 3. The liquid discharging method according to claim 2, wherein the temperature of the liquid in the second liquid flow path is adjusted by heat generated by the heating element provided in the bubble generation area. . 4. The apparatus according to claim 1, wherein the temperature of the liquid in the second liquid flow path is adjusted by heat generated by another heating element different from the heating element provided in the bubble generation area. 3. The liquid discharging method according to 2. 5. The liquid discharging method according to claim 4, wherein said another heating element is provided in a common liquid chamber communicating with a plurality of said second liquid flow paths. 6. The heat applies a pressure to the movable member to such an extent that the movable member is displaced toward the first liquid flow path and the liquid in the first liquid flow path is discharged from the discharge port. A bubble to be given is not generated.
The liquid discharging method according to any one of the above items. 7. The head, comprising: a plurality of first liquid flow paths;
A plurality of second liquid flow paths individually corresponding to the plurality of first liquid flow paths, and adjusting a temperature of the liquid in the second liquid flow path by the plurality of second liquid flow paths. The method according to claim 1, wherein the method is performed for each liquid flow path. 8. The head, comprising: a plurality of first liquid flow paths;
A plurality of second liquid flow paths individually corresponding to the plurality of first liquid flow paths, and adjusting a temperature of the liquid in the second liquid flow path by the plurality of second liquid flow paths. The method according to claim 1, wherein the method is performed for the entire liquid flow path. 9. The method according to claim 2, wherein the temperature of the liquid in the second liquid flow path is adjusted by cooling an element substrate provided with the heating element. The liquid discharging method according to the above. 10. A liquid containing a color material emulsified or dispersed in water is supplied to the first liquid flow path, and the liquid not containing the color material is supplied to the second liquid flow path having the bubble generation region. 10. The method according to claim 1, wherein the liquid is supplied. 11. The liquid discharging method according to claim 10, wherein the color material emulsified or dispersed in water is a color material insoluble or hardly soluble in water. 12. A first liquid flow path communicating with a discharge port, a second liquid flow path having a bubble generation area, and a first liquid flow path between the second liquid flow path and the first liquid flow path. A separating wall provided, and a movable member formed on the separating wall, having a free end on the discharge port side, and disposed between the first liquid flow path and the bubble generation region, A bubble is generated in the bubble generation region, a free end of the movable member is displaced toward the first liquid flow path based on a pressure generated by the bubble, and the pressure is changed to the first pressure by the displacement of the movable member. A liquid discharge head that discharges liquid by guiding the liquid to a discharge port side of a liquid flow path, comprising: a liquid in the second liquid flow path; and a liquid in the first liquid flow path through the separation wall. A liquid discharge head comprising a temperature adjusting means for adjusting a temperature. 13. The heating device according to claim 12, wherein the temperature adjusting means is provided in the second liquid flow path and is a heating element different from the heating element forming the bubble generation region. The liquid ejection head according to any one of the preceding claims. 14. The liquid discharge head according to claim 13, wherein the temperature adjusting unit is a cooling unit that cools an element substrate provided with a heating element forming the bubble generation region. 15. The cooling means for supplying a coolant to at least a part of the element substrate, and adjusting the temperature of the coolant supplied by the coolant supply means so as to contact the element substrate. 15. The liquid ejection head according to claim 14, further comprising a refrigerant temperature adjusting unit. 16. The liquid discharge head according to claim 12, wherein the separation wall is made of a heat conductive material. 17. The liquid discharge head according to claim 16, wherein the heat conductive material is a metal material. 18. The liquid ejection head according to claim 13, wherein the another heating element is provided in a common liquid chamber communicating with a plurality of the second liquid flow paths. 19. The liquid according to claim 12, wherein the liquid supplied to the first liquid flow path and the liquid supplied to the second liquid flow path are different liquids. Discharge head. 20. The liquid supplied to the first liquid flow path is a liquid containing a coloring material emulsified or dispersed in water,
20. The liquid ejection head according to claim 19, wherein the liquid supplied to the second liquid flow path does not include the coloring material. 21. The liquid ejection device according to claim 13, wherein the heating element is an electrothermal converter having a heating resistor that generates heat by receiving an electric signal. head. 22. The liquid discharge head according to claim 21, wherein the electrothermal transducer has a protective film disposed on the heating resistor. 23. A head cartridge comprising: the liquid ejection head according to claim 12; and a liquid container for holding a liquid supplied to the liquid ejection head. 24. The head cartridge according to claim 23, wherein the liquid discharge head and the liquid container are separable. 25. The head cartridge according to claim 24, wherein the liquid container is refilled with a liquid. 26. The head cartridge according to claim 24, wherein the liquid container is provided with a liquid inlet for refilling the liquid. 27. A liquid discharge head according to claim 12, wherein a first liquid is supplied to a first liquid flow path, and a second liquid is supplied to a second liquid flow path. And a liquid container for holding a liquid. 28. A liquid discharge head according to claim 12, further comprising: drive signal supply means for supplying a drive signal for discharging a liquid from the liquid discharge head. Liquid ejection device. 29. A liquid discharge head according to claim 12, further comprising: a temperature adjusting unit configured to cool the liquid in the second liquid flow path of the liquid discharge head to adjust the temperature. Characteristic liquid discharge device. 30. A liquid discharge apparatus which discharges the liquid from the discharge port of the liquid discharge head according to any one of claims 12 to 22, and performs recording by attaching the liquid to a cloth. . 31. A liquid discharge apparatus according to claim 12, wherein a plurality of the discharge ports of the liquid discharge head are arranged over the entire width of a recordable area of a recording medium. . 32. A head kit comprising: the liquid ejection head according to claim 12; and a liquid container holding a liquid supplied to the liquid ejection head. 33. A liquid discharge head according to claim 12, a liquid container holding liquid supplied to the liquid discharge head, and a liquid for filling the liquid container with liquid. 33. The head kit according to claim 32, further comprising: filling means. 34. The head kit according to claim 32, wherein the liquid is ink for performing recording.