JP2000318173A - Ink jet recording head, ink jet recording apparatus and method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To lower the resistance of a seal liquid at the time of discharge of ink. SOLUTION: A heat 10 is equipped with the ink discharge orifice 12 provided to an ink discharge surface, a discharge means 14 and an ink sump 18 for supplying ink to the discharge chamber 16. The discharge means 14 draws in a seal liquid so as to separate the same into the seal liquid 22A positioned at the ink discharge orifice 12 and the seal liquid 22B positioned around the ink discharge orifice 12 to discharge ink in this state. Therefore, when a plurality of the ink discharge orifices are provided, the drawing-in of the seal liquid and the discharge of ink can be performed at every discharge orifice and, as a result, the seal liquid can be drawn in without being lost and ink can be discharge in the optimum drawn-in state at every discharge orifice.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording head, an ink jet recording apparatus, and an ink jet recording method, and more particularly, to an ink jet recording head and an ink jet recording apparatus for sealing an ink discharge port for discharging ink with a sealing liquid. And an ink jet recording method.

[0002]

2. Description of the Related Art In a conventional ink jet recording apparatus, it is a major problem to prevent nozzle clogging due to drying and thickening of ink during non-operation. Various ink materials have been developed to solve this problem, but it is still difficult to reduce evaporation of the ink solvent. In a commercially available ink jet recording apparatus, at the time of non-printing or during a long period of non-operation, the nozzle and the outside air are shielded by a capping means made of resin or the like to delay the drying of the ink. However, this capping means
In order to more effectively increase the airtightness of the nozzle, complicated procedures and devices are required. Also, with this capping means, the nozzle cannot be completely shielded from the air, and during storage, the drying and thickening of the ink inside the nozzle gradually progress, which may cause nozzle clogging. is there.

[0003] In a commercially available ink jet recording apparatus, various maintenance operations are required in order to recover clogging of nozzles due to long-term suspension. For example, in the recovery by a vacuum operation in which a clog in the nozzle is pulled out from the outside of the nozzle by a negative pressure, a pump and an absorber of waste ink are required in the device, which complicates and enlarges the device, and increases the cost of the device. I have. Further, since the nozzle surfaces are collectively made to have a negative pressure, a large amount of ink is also sucked out from nozzles where no clogging occurs and discarded, thereby increasing running costs. In addition, in the case where the recovery is performed by repeating the dummy jet operation and the wiping operation, the device becomes complicated, for example, a mechanism for moving the head to the maintenance position or pressing a member such as a blade against the head surface to perform a sliding motion is required. Cost increases. After a long-term suspension of the inkjet recording apparatus, a maintenance operation is performed by combining these operations before printing, and a waiting time before printing and noise due to the maintenance operation are generated, which is disadvantageous to the user.

As means for avoiding the problem caused by clogging after a long period of suspension, as disclosed in Japanese Patent Application Laid-Open No. 52-104130, a film of a seal liquid insoluble in ink and a film of the seal liquid are provided. There is known a method in which the ink discharge port is sealed by means to shield the ink from the air and prevent the ink from drying.

Japanese Patent Application Laid-Open No. 49-115548 discloses that a seal liquid and a wetting mechanism seal an ink discharge port when the printing apparatus is not operating, and a seal liquid supply path is provided by a switch provided in a seal liquid supply path during operation. A method for stopping the supply of the water is described.

However, these methods have a disadvantage that the resistance of ink discharge is high at the start of discharge because the seal liquid is separated on the surface but is substantially continuous with the surrounding seal liquid inside. are doing. When the temperature of the environment in which the printing apparatus is used becomes low, the viscosity of the seal liquid may increase, and in the worst case, there is a problem that ink cannot be ejected.

Japanese Patent Application Laid-Open No. 54-69436 discloses a method of forming and releasing a seal liquid film in order to improve the ejection stability of ink droplets in a sealing method using a seal liquid.

JP-A-5-177841 describes a method of sealing a nozzle with a seal liquid as necessary, and a method of opening and closing a seal with a seal liquid in conjunction with carriage scanning.

However, in either method, switching between the state of being sealed by the sealing liquid and the state of being unsealed requires an external force such as opening and closing by a pump, an electromagnet, and a support, and the structure of the head is complicated. This leads to an increase in the size of the printing apparatus.

[0010]

As described above, in the conventional method of sealing a nozzle with a sealing liquid, the worst case is when the sealing liquid has a high resistance at the time of discharge and the viscosity of the sealing liquid increases due to an environment change. The case (1) has a disadvantage that ink cannot be ejected. In general, many non-volatile liquids having a low vapor pressure have a high kinematic viscosity due to a large molecular weight. Therefore, it is desirable to select a seal liquid having a high kinematic viscosity in order to make the seal liquid non-volatile for a longer period of time and maintain the sealing performance against clogging. Therefore, in order to adopt a specification that prevents clogging for a longer period of time, a sealing liquid having a high kinematic viscosity must be used, or the thickness of the sealing liquid must be increased, and the discharge resistance further increases. As a result, it becomes difficult to achieve both clogging prevention performance and discharge performance. If means for opening and closing the seal of the seal liquid is provided to avoid these problems, the apparatus becomes complicated and large.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the related art, and has as its object to provide an ink jet recording head and an ink jet recording capable of reducing the resistance of a seal liquid at the time of ink ejection. An apparatus and an inkjet recording method are provided.

[0012]

According to the first aspect of the present invention, there is provided an ink discharge port for discharging ink, a sealing liquid for sealing the ink discharge port, and
A first function of drawing the seal liquid into the ink discharge port so that the seal liquid of the seal liquid positioned at the ink discharge port and the seal liquid of the seal liquid positioned around the ink discharge port are separated; A second function of ejecting ink from the ink ejection port in response to an input image signal.

That is, the seal liquid is supplied to the ink discharge port automatically or manually. When the ink discharge unit attempts to discharge ink from the ink discharge port while the ink discharge port is sealed with the seal liquid, the seal liquid positioned at the ink discharge port of the seal liquid due to the viscosity of the seal liquid. Not only that, the seal liquid positioned around the ink outlet of the seal liquid also tries to prevent ink discharge.

Therefore, according to the present invention, the ink discharging means comprises:
The seal liquid is drawn into the ink discharge port so that the seal liquid positioned at the seal liquid ink discharge port and the seal liquid positioned around the seal liquid ink discharge port are separated. The ink discharging means is driven in two modes, a mode for executing the first function and a mode for executing the second function.

As described above, the seal liquid is drawn into the ink discharge port so that the seal liquid located at the ink discharge port of the seal liquid and the seal liquid located around the ink discharge port of the seal liquid are separated. In the case where the ink is to be ejected from the ink ejection port, it is possible to eliminate the effect of preventing the seal liquid located around the ink ejection port from ejecting the ink, and to stably eject the ink.

In particular, according to the present invention, the ink discharge means is arranged so that the seal liquid positioned at the ink discharge port of the seal liquid and the seal liquid positioned around the ink discharge port of the seal liquid are separated as described above. Has a first function of drawing ink into the ink ejection ports and a second function of ejecting ink. Therefore, when there are a plurality of ink ejection ports, the sealing liquid is drawn and the ink is ejected for each ejection port. Therefore, the seal liquid can be drawn in without any loss, and the ink can be discharged in an optimum drawing state for each discharge port.

Here, the ink discharge means may change the volume in the discharge chamber.
Thus, the amount of ink drawn in can be set to a predetermined value with high accuracy. The drawing of the sealing liquid increases the volume, and in this state, the volume is reduced to discharge the ink.

The ink discharging means may include a piezoelectric member and deform the piezoelectric member to execute the first function and the second function. Thus, the first function and the second function can be executed with high accuracy. That is, since the deformation of the piezoelectric member can be controlled with high accuracy by an electric signal, high image quality can be achieved.
In this case, the ink discharge means controls the area of the piezoelectric member to which the electric field is applied, thereby controlling the first area.
And the second function may be executed. As in claim 5, the electrodes provided on at least one side of the piezoelectric member are constituted by a plurality of electrodes having different areas, and the electrodes are switched to apply an electric field. By doing so, the first function and the second function are executed, and the electrode provided on at least one side of the piezoelectric member is constituted by a plurality of electrodes as in claim 6, and the number of selected electrodes By applying an electric field while changing the
And the second function may be executed.

According to a seventh aspect of the present invention, the first function and the second function are executed by controlling the thickness of the piezoelectric member for applying an electric field to the plurality of piezoelectric members stacked on each other. Is also good. In this case, as in claim 8, a plurality of piezoelectric members having different thicknesses and electrodes are alternately stacked in the thickness direction of the piezoelectric member, and the first electrode is applied by switching the electrodes to apply the electric field. And executing the second function and the second function.
A plurality of piezoelectric members and electrodes are alternately stacked in the thickness direction of the piezoelectric member, and the number of selected electrode sets is changed, and at the same time, an electric field is applied between the selected pairs of electrodes. By doing so, the first function and the second function may be executed.

By the way, a holding means for holding a state in which the sealing liquid is drawn may be provided. In this manner, if the retracted state is maintained, a plurality of ink discharges can be performed in the retracted state, and the seal liquid does not need to be retracted for each ink discharge, and the ink discharge interval can be shortened. it can.

[0021] The holding means may be as follows.
By continuing the execution state of the first function when the sealing liquid is drawn in, the drawn-in state may be maintained. As described in claim 13, a plurality of ink discharges can be performed in the pulled-in state, that is, the drawing-in operation can be prevented every time the ink is discharged, and the discharge interval can be shortened.

[0022] According to a fourteenth aspect, an output means for outputting a release signal for releasing the state in which the sealing liquid has been drawn into the original state to the sealing liquid drawing means may be provided.

If the retracted state is quickly returned each time by the retracting release signal, each discharge port 12 can be uniformly sealed by the sealing liquid (see FIG. 5B), so that the ink is converted into air. This has the effect of shortening the exposure time and more effectively preventing the increase in ink viscosity due to drying and the occurrence of nozzle clogging. Furthermore, it is possible to make the state before each pull-in the same state and prepare for the next ejection cycle, and this has an effect that ejection is more stable and higher image quality can be achieved.

On the other hand, the ink discharge means is controlled so that the drawing of the seal liquid and the discharge of the ink are completed within a predetermined basic discharge period after outputting the pull-in signal. May be provided.

As described above, when the drawing of the sealing liquid and the discharging of the ink are completed within a predetermined basic discharging period after the output of the drawing signal, the drawing and the discharging of the ink can be executed regularly, and the discharging of the ink can be performed. It can be performed stably.

The control means may control the ink discharge means so as to discharge the ink after a predetermined delay time from the output of the pull-in signal. Further, the control means may variably control the predetermined delay time. That is, the predetermined delay time can be variably controlled according to a change in the environment or the state of the head. Therefore, even if the environment changes, the control can be performed in an optimum time, and the ink can be stably ejected.

[0027] The control means may be as follows.
The ink discharge unit may be controlled so as to execute the drawing of the sealing liquid every time the image signal is input. Thereby, the control of drawing in the sealing liquid can be performed as needed, and unnecessary control can be eliminated.
In other words, when the sealing liquid is drawn every time the pull-in signal is output, the sealing liquid can be drawn into each ink ejection port individually, thereby eliminating unnecessary control. it can.

[0028] Further, the control means may be as follows.
Driving is performed in two modes, a mode for drawing in the seal liquid and a mode for discharging ink.

[0029] Further, the control means includes:
The ink discharging means may be controlled so as to draw in the sealing liquid every time before discharging the ink.

The ink jet recording apparatus may include the ink jet recording head according to any one of the first to twentieth aspects.

In the ink jet recording method for an ink jet recording apparatus according to the present invention, the seal liquid is drawn at least before the ink is ejected.

In this case, as in claim 23, the state where the sealing liquid is drawn in is maintained, and as in claim 24, when the sealing liquid is maintained in the drawn state, ink is discharged. You may make it discharge several times.
Further, the seal liquid may be drawn in every time before the ink is ejected.

[0033]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) A first embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a basic configuration example of the ink jet recording head 10 of the present embodiment. The ink jet recording head 10 of the present embodiment (hereinafter simply referred to as “head 1
0) is provided with an ink discharge port 12 provided on the ink discharge surface, a discharge chamber 16 provided with a discharge means 14 also serving as a drawing means, and an ink reservoir 18 for supplying ink to the discharge chamber 16. ing. The head 10 is provided with the head 1 by an action caused by, for example, a capillary force or a pressure difference.
The ink is supplied from an external ink tank 30 and an ink supply path 28 (not shown).

FIG. 1 shows only one ink ejection port 12, but a plurality of ink ejection ports 12 may be provided on the ink ejection surface. Although the drawing shows the ink discharge ports 12 arranged in the horizontal direction for the sake of convenience, the ink discharge direction, that is, the arrangement direction of the recording head 10 can be appropriately selected as desired, and a general Is ejected in the direction of gravity (downward).

The seal liquid usable in the present embodiment seals the ink discharge ports 12 and
Has a function of shielding the ink from the air. The seal liquid that maintains such a function contains at least a component insoluble in the ink, is incompatible with the ink, and does not spontaneously emulsify with the ink.

In order for the sealing liquid and the ink to be incompatible, specifically, the solubility of the sealing liquid in the ink is 0.1% by weight or less in an environment where the head 10 or the recording apparatus is used. Is preferred.

Further, when the sealing liquid is non-volatile,
This is preferable because the liquid does not evaporate while the head 10 is at rest and the sealing liquid does not change the sealing state of the discharge port 12. Non-volatile refers specifically to a vapor pressure of 0.1 mmHg or less under an environment in which the head 10 or the recording device is used.

The kinematic viscosity of the seal liquid that can be used in the present embodiment is determined by setting the period for preventing clogging, the diameter of the discharge means 14 and the discharge port 12, the discharge frequency of the recording head 10, the film thickness of the seal liquid, and the seal liquid. It can be appropriately selected according to design specifications such as a method of arrangement, and the kinematic viscosity can be widely used from low viscosity to high viscosity. However, in general, many non-volatile liquids having a low vapor pressure have a high kinematic viscosity due to a large molecular weight. For this reason, it is desirable to select a seal liquid having a high kinematic viscosity to maintain the sealing performance against clogging by making the seal liquid non-volatile for a longer period of time. Considering this, the kinematic viscosity of the sealing liquid in the environment where the head 10 or the recording device is used is preferably in the range of 1 to 200 mm ² / s.

The surface tension of the sealing liquid which can be suitably used in the present embodiment is in the range of 15 to 70 mN / m in an environment where the head 10 or the recording apparatus is used. In order for the sealing liquid to wet, the pressure is preferably 50 mN / m or less, and more preferably smaller than the surface tension of the ink used.

A liquid originally suitable for these properties may be used alone, or a plurality of materials may be mixed to adjust the viscosity or surface tension to a preferred range before use.

When a water-based ink is used, an organic solvent or oil that is liquid at normal temperature can be used as the seal liquid. For example, octane, nonane, tetradecane,
Hydrocarbons such as dodecane, higher fatty acids such as oleic acid and linoleic acid, water-insoluble alcohols such as n-decanol and dimethylbutanol, and plasticizers such as dibutyl phthalate and dibutyl maleate can be used. Alternatively, vegetable oil, mineral oil, silicone oil, fluorine oil and the like can be used. These may be used alone or in combination of two or more as long as they can be mixed uniformly.

Before starting printing, the seal liquid is applied to a brush, cloth,
The ink is supplied to the ink ejection surface by a method such as coating with a blade. In this case, the supply of the sealing liquid may be manual or automatic. In addition, a tube or a porous member is arranged near the ink ejection surface, and a mechanism for supplying a sealing liquid to the ink ejection surface by a capillary force, surface tension, a pressure difference, or the like is provided. Is also good. The seal liquid 22 supplied to the ink ejection surface by these methods is as shown in FIG.
As shown in (1), a film of the seal liquid is formed on the ink surface of the ink discharge port 12.

In the present embodiment, the thickness of the seal liquid on the ink discharge surface is determined by the period during which the sealing performance is maintained, the diameter of the discharge means 14, the diameter of the discharge port 12, the discharge frequency of the recording head 10, and the kinematic viscosity of the seal liquid. It can be set as appropriate with respect to design specifications such as a method of arranging the sealing liquid. However,
Taking into account the sealing performance against clogging and the fact that ejection is performed with lower energy, it is preferable that the thickness be 1 μm or more and 200 μm or less. The film thickness of the sealing liquid is, for example,
It can be controlled by adjusting the supply amount of the sealing liquid, or by forming the periphery of the recording head 10 or the like into a shape that regulates the holding amount of the sealing liquid.

The sealing liquid may be arranged in the ink jet recording head 10 in advance, or may be supplied to the ink jet recording head 10 as needed.

As shown in FIG. 1, the discharge means 14 discharges the seal liquid 22 so that the seal liquid 22A located at the ink discharge port 12 and the seal liquid 22B located around the ink discharge port 12 are separated. In addition to having a function of drawing into the ink ejection port 12, while being separated in this manner,
It has a function of discharging ink from the discharge port 12. The amount of the sealing liquid to be drawn is appropriately selected depending on the kinematic viscosity of the sealing liquid, the surface tension, the diameter of the discharge port, the shape of the discharge port, and the like. As an example, in the case of a configuration in which the shape of the discharge port does not change the cross-sectional area in the discharge direction, it is possible to satisfactorily separate the shape by drawing in the seal liquid film thickness or more. As described above, in order to have the function of drawing in and the function of discharging, the discharging means 14 pulls in the pressure of the discharge chamber 16 at a negative pressure with respect to the pressure outside the discharge port 12 and sets the pressure in the retracted state as a reference. At a positive pressure (meaning a relative pressure, not an absolute pressure). That is, for example, the discharge unit 14 pulls the pressure of the discharge chamber 16 into a strong negative pressure (absolute pressure) with respect to the pressure outside the discharge port 12, and changes the strong negative pressure to a weak negative pressure (absolute pressure). To discharge. Or return to the same pressure as the outside pressure,
It is also possible to adjust the volume and speed of the ejected ink droplet so that the pressure becomes absolute positive with respect to the external pressure.

There are various methods for generating the negative pressure and the positive pressure. In the present embodiment, since the positive pressure and the negative pressure can be controlled with good responsiveness and small, as shown in FIG. It is preferable to use a method of increasing the volume of the chamber 16 to generate a negative pressure and reducing the volume of the discharge chamber 16 to generate a positive pressure. In the case of the present invention, the discharge means 14 is arranged on the wall surface or the bottom surface of the discharge chamber 16 and deforms the wall surface or the bottom surface of the discharge chamber 16 so that the volume of the discharge chamber 16 increases / decreases. As shown in FIG. 3, in the head 10 having a plurality of discharge ports 12, a discharge unit 14 serving as a drawing-in unit is provided according to each of the discharge ports 12.

As a method of causing the above-described deformation,
Electrostrictive materials, magnetostrictive materials, and the like can be used. Also,
The deformation may be caused by combining these deformable members with an elastic member such as a spring material or a rubber material, or the elastic member may be deformed by applying a magnetic force or an electrostatic force to the elastic member. The deformable member, the elastic member, and the like may be made of a plurality of materials.

Of these methods, the use of a piezoelectric member is a preferable method because the deformation behavior can be controlled with high accuracy by an electric signal, so that high image quality can be achieved. That is, as shown in FIG. 4, for example, an elastic member 42 is provided as a part of the inner wall of the discharge chamber 16, and the piezoelectric member 38 is fixed to the elastic member 42. In particular, piezoelectric members have been put to practical use in devices such as ink jet heads and vibrators, and advanced manufacturing technology has been established.Therefore, various shapes and materials can be appropriately selected according to the specifications of the device. As it enables a small head design with low cost,
It is suitable for use in a method of changing the volume of the discharge chamber 16.

As the piezoelectric member, there can be widely used materials used for a vibrator or the like which generates distortion or deformation when an electric field is applied. For example, thin films of polycrystals and single crystals, such as quartz, lead zirconate titanate (PZT), barium titanate, lead niobate, lithium niobate, bismuth germanate, and lithium tantalate, zinc oxide, and aluminum nitride Use of an inorganic piezoelectric material consisting of, or a piezoelectric polymer material such as polyurea, polyvinylidene fluoride (PVDF) or a copolymer of PVDF, or a composite piezoelectric material of an inorganic piezoelectric material and a piezoelectric polymer material You can also.

As shown in FIG. 5A, the discharge means 14 also serving as the drawing means is divided into a drawing mode in which the discharge means 14 operates to separate the drawn sealing liquid 22A from the surrounding sealing liquid 22B. There is an ejection mode in which the ejection unit 14 operates so that ink droplets are ejected in accordance with an image signal later. In the present embodiment, the ink is ejected in the ejection mode in the ejection mode by operating in the ejection mode before ejection to make the ejection state.

In order for the discharge means 14 also serving as the drawing means to operate in the drawing mode, a negative pressure is generated to separate the sealing liquid and the drawing is performed. When a negative pressure is generated by deformation, the amount of deformation is adjusted so that a necessary volume is drawn. In addition, the amount of pull-in required for separation is determined by the diameter of the discharge port 12, the thickness of the seal liquid,
The optimum value is appropriately set according to design values such as the kinematic viscosity of the sealing liquid and the surface tension of the sealing liquid. Further, the pull-in amount may be variably controlled in response to a case where these conditions change due to an environment or the like.

In the case where the sealing liquid is drawn in and separated, especially in the case where the sealing liquid film thickness is set to be large in order to maintain the performance of clogging for a longer period of time, the amount of drawing-in required for separation may be large. is there. If the conditions for the generation of the negative pressure in the pull-in and the conditions for the generation of the positive pressure in the ejection mode are not significantly different, the polarity and the voltage of the applied voltage are set to be optimal for each mode. When the condition difference between the two modes is large, for example, the necessary deformation can be obtained by changing the effective area of the member to be deformed or the action direction of the electric field causing the deformation depending on the mode. When a piezoelectric member is used, in addition to increasing the amount of deflection of the piezoelectric member by increasing the applied voltage, the effective area of the deformable portion of the piezoelectric member is increased, and the drawing volume caused by the deformation is increased. Alternatively, the deformation can be increased by changing the thickness of the applied electric field. In these cases, for example, the electrodes to be used are switched in two modes to perform different driving.

To change the effective area of the deformable portion of the piezoelectric member, a method of controlling the area for applying an electric field to the piezoelectric member is used. In order to control an area for applying an electric field to the piezoelectric member, a method of switching a plurality of electrodes provided on the piezoelectric member between a drawing mode and a discharge mode is used. For example, as shown in FIGS. 17 (A) and 17 (B), the electrodes provided on at least one side of the piezoelectric member 38 are constituted by a plurality of electrodes (40B1, 40B2) having different areas. The area for applying the electric field to the piezoelectric member 38 is controlled by switching the electrodes and applying the electric field.
Alternatively, as shown in FIGS. 18 (A) and 18 (B), the electrodes provided on at least one side of the piezoelectric member 38 are constituted by a plurality of electrodes (40B1, 40B2, 40B3), and are selected in a pull-in mode and a discharge mode. By changing the number of electrodes (for example, 4
The three electrodes 0B1, 40B2, and 40B3 are selected, and only one electrode of 40B2 is selected in the ejection mode.) An electric field is applied to control the area where the electric field is applied to the piezoelectric member. The shape of the plurality of electrodes can be appropriately set to an optimum shape depending on the shape of the discharge chamber and the discharge means. For example, the electrodes are configured by arranging a plurality of rectangular electrodes or by combining comb shapes. Alternatively, as shown in FIG. 6, it is also possible to form a plurality of electrodes by forming another electrode around one electrode. Further, the plurality of electrodes may be provided on both sides of the piezoelectric member, but it is also possible to configure one electrode in the thickness direction of the piezoelectric member as a common electrode with respect to the other electrode on the other side, in this case, The electrode manufacturing process is simplified.

The switching of the electrodes in the pull-in mode and the discharge mode is performed by a switch, but the voltage applied to each electrode may be changed to a preset voltage simultaneously with the switching. By changing the applied voltage for each mode, the size and speed of the ink droplet to be ejected can be set appropriately, and the control to keep the size and speed of the ejected ink droplet stable depending on the usage environment of the printing device is also possible. Further, it is also possible to continue to apply a bias-like voltage for maintaining the drawn state as described later. The voltage to be applied may be set differently for each electrode.

As shown in FIG. 6, for example, an elastic film 42 is provided via a protective layer 44 as a part of the inner wall of the discharge chamber 16. A piezoelectric member (PZT layer) 38 sandwiched between the common electrode 40A, the first electrode 40B1, and the second electrode 40B2 is fixed to the elastic film 42 to form a discharging unit. The common electrode 40A and the first electrode 40B1 are connected via a power supply and a switch SW2, and the common electrode 40A and the second electrode 40B2 are connected via the power supply and a switch SW1. Note that an insulating layer 40C is arranged between the first electrode 40B1 and the second electrode 40B2.
As shown in FIG. 6A, the total area of the first electrode 40B1 and the second electrode 40B2 is larger than the area of the first electrode 40B1.

Here, the switch SW1 and the switch SW
2, the first electrode 40B1 and the second electrode 40
A voltage is applied to B2, and the piezoelectric member having the combined area of the first electrode 40B1 and the second electrode 40B2 is deformed. As a result, the amount of deformation required for the pull-in mode can be obtained. When the switch SW2 is opened in this state, the deformation of only the shape corresponding to the area of the second electrode 40B2 is released, and the deformation of the volume required for the ejection mode (relatively, the head 1).
(Deformation in the direction of decreasing the volume inside the zero), it is possible to obtain a positive pressure necessary for ejection. Note that, if the deformation of the volume required for the ejection mode is obtained, the voltage of the second electrode 40B2 is not limited to 0 V and can be set to an optimal voltage.

As described above, the drawing mode and the ejection mode can be executed by controlling the area of the piezoelectric member to which the electric field is applied. That is, when increasing the drawing volume, the area to which the electric field of the piezoelectric member is applied in the drawing mode is made larger than the area that causes the deformation of the piezoelectric member in the ejection mode (in the above example, the electric field is released). .

A large number of small electrodes are arranged on the piezoelectric member instead of the first and second electrodes, and the area of the piezoelectric member to which the electric field is applied in the pull-in mode is equal to the piezoelectric member in the ejection mode. Alternatively, a voltage may be selectively applied to the electrodes so as to be larger than the area that causes the deformation. Further, it is also possible to increase the area that causes deformation of the piezoelectric member in the discharge mode, compared to the area where the electric field of the piezoelectric member is applied in the retracting mode. In this case, with respect to the volume change in the retracting mode,
By increasing the volume change in the ejection mode, the volume and speed of the ejected ink droplet can be set larger.

To change the thickness of the deformable portion of the piezoelectric member, a method of controlling the thickness of the piezoelectric member to which an electric field is applied in the piezoelectric members stacked in the thickness direction is used.
In order to control the thickness of the piezoelectric member to which an electric field is applied, a method is used in which a plurality of electrodes stacked in the thickness direction of the piezoelectric member are switched between a drawing mode and a discharging mode.
For example, as shown in FIGS. 19A and 19B, a plurality of piezoelectric members (PZT layers) having different thicknesses in the thickness direction of the piezoelectric member.
(38A, 38B: 38A thickness <38B thickness) and electrodes (40A, 40B1, 40B)
2) are alternately laminated, and the electrodes are switched between the pull-in mode and the discharge mode (for example, 40 in the pull-in mode).
An electric field is applied (switching to select the electrodes B1 and 40B2 and selecting the electrodes 40A and 40B1 in the discharge mode) to control the thickness of applying the electric field to the piezoelectric member. Alternatively, as shown in FIGS. 20A and 20B, a plurality of piezoelectric members (PZT layers) (38A,
8B) and the electrodes (40A, 40B1, 40B2) are alternately stacked, and the number of sets of electrodes selected in the pull-in mode and the discharge mode is changed (for example, 40 in the pull-in mode).
Select two sets of electrodes 40B1 for 40A and 40B2 for 40B1, and select one of 40B1 and 40B2 in the ejection mode.
At the same time, an electric field is applied between the selected pairs of electrodes (for example, 40A and 4A in the pull-in mode).
0B1, and an electric field is applied between 40B1 and 40B2), and the thickness of applying the electric field to the piezoelectric member is controlled. The thickness of the piezoelectric member between the electrodes is set to an optimum value for each mode, but it is also possible to provide a dielectric layer to adjust the amount of deformation. The shape of these multiple electrodes is
The shape can be appropriately set to an optimum shape depending on the shape of the discharge chamber and the discharge means. For example, as shown in FIG. 7, a plurality of rectangular electrodes of the same type are alternately stacked with the piezoelectric member (PZT layer).

The switching of the electrodes between the pull-in mode and the discharge mode is performed by a switch, but the voltage applied to each electrode may be changed to a preset voltage simultaneously with the switching. By changing the applied voltage for each mode, the size and speed of the ink droplet to be ejected can be set appropriately, and the control to keep the size and speed of the ejected ink droplet stable depending on the usage environment of the printing device is also possible. Further, as described later, it becomes possible to continue applying a bias-like voltage for maintaining the drawn state.

As shown in FIG. 7, for example, an elastic film 42 is provided as a part of the inner wall of the discharge chamber 16 via a protective layer 44. On the elastic film 42, a common electrode 40A, a first piezoelectric member (PZT layer) 38A, a first electrode 40B1, a second piezoelectric member (PZT layer) 38B, and a second electrode 40B2 are sequentially stacked. The discharge means is formed by being fixed.

The first piezoelectric member (PZT layer) 38A and the second piezoelectric member (PZT layer) 38B are polarized in the thickness direction, and the common electrode 4 is applied so that a voltage is applied in the positive direction.
0A, a first electrode 40B1, and a second electrode 40B2 are connected to a power supply via switches SW1, SW2.

Here, when the switches SW1 and SW2 are closed, an electric field is applied to the first piezoelectric member (PZT layer) 38A and the second piezoelectric member (PZT layer) 38B, so that the entire piezoelectric member is largely deformed and retracted. The amount of deformation required for the mode can be obtained. When the switch SW2 opens in this state,
The application of the electric field to the second piezoelectric member (PZT layer) 38B is interrupted, so that the deformation of the second piezoelectric member (PZT layer) 38B is released, and the volume required for the ejection mode (relatively the head (Deformation in the direction of decreasing the volume inside 10), it is possible to obtain a positive pressure necessary for ejection. If the deformation required for the ejection mode is obtained, the second piezoelectric member (P
The electric field of the (ZT layer) 38B can be set to an optimum value.

As described above, the pull-in mode and the discharge mode can be executed by controlling the number of applied electric fields in the plurality of (two in the above example) piezoelectric members stacked. When increasing the drawing volume, the number of piezoelectric members to which an electric field is applied in the drawing mode is set to be larger than the number of piezoelectric members that cause deformation in the discharging mode. Further, it is possible to increase the number of piezoelectric members that cause deformation in the ejection mode, rather than the number of piezoelectric members that apply an electric field in the drawing mode. And the volume and speed of the ejected ink droplet can be set to be larger.

In the drawing mode, when the sealing liquid is gradually drawn in over time, a part of the sealing liquid around the discharge port 12 also flows in and is drawn together, so that the drawing amount until the separation is increased. Therefore, if a negative pressure for pull-in is applied in a short time and the pull-in is performed quickly, the amount of pull-in until the separation can be reduced. As a result, the size and the amount of deformation of the retracting means can be reduced, and the device can be downsized. Further, when the pull-in is performed in a shorter time, there is an advantage that the ejection frequency can be increased and the time required for printing can be reduced. That is, it is preferable that the rising time from the start of the application of the negative pressure to the application of the maximum negative pressure be short.

In order for the discharge means 14 also serving as the drawing means to operate in the discharge mode, the ink and the sealing liquid drawn into the discharge chamber 16 by applying a positive pressure (relative positive pressure) from the separated and drawn state. Discharge. If the discharge chamber 16 is deformed and pulled in, the discharge chamber 16 is deformed so as to reduce its volume and a positive pressure is applied. When the piezoelectric member is deformed and ejected, the voltage is changed in a direction in which the deformation of the piezoelectric member is restored with respect to the potential applied at the time of drawing, so that the piezoelectric member is deformed to apply a positive pressure. As the potential, an optimal potential is appropriately selected with respect to the diameter of the discharge port 12, the thickness of the seal liquid, the kinematic viscosity of the seal liquid, the surface tension of the seal liquid, the diameter and speed of the ink droplet to be discharged.

Next, the operation of the present embodiment will be described.

According to the present invention, the seal liquid is drawn into the discharge port 12 by the discharge means 14 also serving as the drawing means before the ink is discharged, and is separated from the seal liquid around the discharge port 12. Specifically, as shown in FIG. 8, before discharging, first, the discharging means 14 operates in the pull-in mode to draw the seal liquid into the discharge port 12, and as shown in FIG. 22A to surrounding sealing liquid 2
Separate with 2B. Next, in the divided state, the discharge means 14 operates in the discharge mode, and discharges the ink in the ink discharge ports 12 together with the seal liquid. At the time of discharge, the seal liquid in the discharge port 12 may not be completely discharged together with the ink. After the printing is completed, as shown in FIG. 5B, the ejection means 14 is returned to the state before being pulled in, the ink in the ink reservoir is re-supplied to the ejection port 12, and the sealing liquid around the ejection port 12 is supplied to the ink ejection port. Twelve inks are sealed to prevent clogging.

When a piezoelectric member is used as the discharging means 14, the applied voltage V1 in the pull-in mode and the applied voltage V2 in the discharging mode can be set to optimal values separately. Further, in the ejection mode, the waveform to be applied is not limited to a rectangular wave, and may be set to a trapezoidal wave, a triangular wave, or an arbitrary waveform so as to optimize the volume and speed of the ejected ink (ink drop). Good.

The state in which the sealing liquid is drawn may be maintained, and a plurality of ejections may be performed in this state.
In this manner, if a plurality of inks are ejected in a state where the seal liquid is drawn in, it is not necessary to perform the drawing operation for each discharge, and the discharge interval can be shortened and the discharge frequency can be increased. Has advantages. This holding uses a method of holding the negative pressure by the discharge means 14 after the pull-in operation. After the printing is completed, the holding is released and the seal is reliably returned to the sealed state, so that clogging can be prevented without unnecessarily exposing the ink at the ejection ports to the air. The release of the holding is performed by releasing the operating state of the retracting means.

In order to maintain the pull-in state while maintaining the negative pressure of the discharging means 14, for example, using a bias applying means (see FIG. 9) for continuously applying a voltage for deforming the discharging means 14 in a bias state. Continue to maintain negative pressure. When the piezoelectric member is used for the ejection unit 14, as shown in FIG. 8, a bias application signal is supplied from the bias application unit to apply a bias-like potential to the ejection unit 14 to maintain the deformation. When an image signal is input, the bias potential is maintained even after driving in the ejection mode according to the image signal (primarily lowering the applied voltage according to the ejection signal). That is, control is performed so as to maintain the state of drawing in the sealing liquid. To release the holding, the bias-like pull-in potential is returned to the reference potential, and the pull-in is returned.

As described above, in the present invention,
The seal liquid is drawn into the discharge port 12 to separate the seal liquid from the surrounding seal liquid to lower the discharge resistance. Hereinafter, preferable means for improving this effect will be described. The discharging means 14 which also serves as the drawing means,
Since the positive pressure and the negative pressure can be controlled with good responsiveness and small, it is preferable to deform the wall surface and the bottom surface of the discharge chamber 16 so that the volume of the discharge chamber 16 increases / decreases. In addition, the use of a piezoelectric member also enables the deformation behavior to be controlled with high accuracy using an electric signal,
This is preferable because high image quality can be achieved.

Further, since the discharge frequency can be increased, it is preferable to perform a plurality of discharges while maintaining the retracted state. In this case, the discharge means 14 maintains the negative pressure.

The ink jet recording apparatus according to the present embodiment comprises an ink ejection port 12, a sealing liquid for sealing the ink ejection port 12, and the ink ejection port 1 according to an image signal.
2 is an ink jet recording apparatus having an ink discharge means 14 for discharging ink from the ink jet head 2 and also serving as a seal liquid drawing means for drawing the seal liquid. With this inkjet recording apparatus, an image is recorded by discharging ink corresponding to an image signal onto an image recording medium. In the ink jet recording apparatus of the present invention, the discharging means 14 which also serves as the drawing means generates a negative pressure at the time of drawing to draw the seal liquid and separates it, and generates a positive pressure at the time of discharging to discharge the ink. Since the pressure can be controlled well, it is preferable to use a method of increasing or decreasing the volume of the discharge chamber 16 to generate the pressure. It is preferable to use a piezoelectric member for the discharging means 14 which also serves as the drawing means, since the behavior of the deformation can be controlled with high accuracy by an electric signal, so that high image quality can be achieved. In addition, since the ejection frequency can be increased, it is preferable to perform a plurality of ejections while maintaining the drawn state.

According to the present embodiment, the seal liquid 22A around the discharge port 12 is separated from the seal liquid 22A around the discharge port 12 by separating the seal liquid 22B around the discharge port 12 from the seal liquid 22B. Therefore, it is possible to eliminate the effect of hindering ink ejection from the ink jet head, thereby reducing the resistance during ejection. For this reason, even in a low temperature environment in which the viscosity of the sealing liquid increases, a clear image can be printed without causing ejection failure. In addition, since the discharge resistance is low, even if the seal liquid to be arranged is thick or a high-viscosity seal liquid material is selected, both performance against clogging and discharge performance can be achieved, preventing clogging for a longer period of time. Such a design of the head 10 is also possible. Also,
In the present embodiment, since the discharge port 12 is sealed by the seal liquid, clogging due to drying of the ink does not occur even after a long period of suspension, so that the discharge operation can be performed immediately when necessary, The subsequent maintenance step can be reduced or omitted. Therefore, the size and cost of the recording device can be reduced,
It is possible to reduce the waiting time before printing and the noise due to the maintenance, which are caused by the maintenance after the long-term suspension, and it is also possible to suppress an increase in the running cost due to a large amount of ink disposal.

In this embodiment, in order to separate the seal liquid 22A located at the ink discharge port 12 from the surrounding seal liquid 22B, the required amount of the seal liquid located at the ink discharge port 12 is drawn. That is, the drawing-in means 24 is driven by a predetermined operation amount within a predetermined time so as to draw a required amount of the sealing liquid located at the ink discharge port 12. By the way, as described in Japanese Patent Application Laid-Open No. 3-132356, there is a method in which a sealing liquid is drawn by solidification shrinkage of hot melt ink. However, in the shrinkage during cooling and solidification, the sealing liquid is drawn in at a slower speed than the drawing in the present embodiment, so that the surrounding sealing liquid gradually flows into the discharge port in accordance with the drawing and cannot be separated. Further, in the retracted state, the ink 21 cannot be discharged because the ink 21 is solidified. Further, in the case of shrinkage during cooling and solidification, a cooling time of several hours is required in the case of a long time from several minutes, whereas in the present embodiment, the time required for retraction is the kinematic viscosity of the sealing liquid, the surface tension, The thickness is appropriately selected depending on the thickness, the diameter of the discharge port, and the shape of the discharge port. In order to effectively separate the discharge port, it is preferable that the pull-in operation is performed within one second.
It is preferred to step in (within seconds) and operate the means. That is, the contents described in JP-A-3-132356 are essentially different from the contents of the present application.

In the present embodiment, the drawing-in means 24 is provided for each of the discharge ports 12. Therefore, if the pull-in is controlled for each discharge of each discharge port 12, it is possible to eliminate unnecessary control of the pull-in for the discharge ports 12 that do not perform the discharge operation, and it is also possible to set such that the optimum pull-in state is selected and discharged. Also, it is possible to draw in the sealing liquid without loss. In addition, since the drawing means and the discharging means 14 are combined, the drawing means and the discharging means 14 can be formed and formed collectively on the same substrate, which simplifies the structure of the head 10 and reduces the cost of the apparatus. Becomes possible. Furthermore, since the driving means of the drawing means and the driving means of the discharge means 14 are also used, the size and the price can be reduced.

[0079]

First Embodiment Hereinafter, the present embodiment will be described in more detail with reference to a first embodiment, but the present embodiment is not limited to this.

As shown in FIG. 9, the head 10 has an ink reservoir 18 inside, and an ink discharge means 14 which also serves as a seal liquid drawing means having a piezoelectric member is provided in a discharge chamber 16 communicating with a discharge port 12 having a diameter of 40 μm. Are arranged.

As the sealing liquid, a liquid prepared by mixing a plurality of types of silicone oils (kinematic viscosity: 30 mm ² /
s, surface tension 20.8 mN / m, specific gravity 1.0). The vapor pressure of this sealing liquid at 25 ° C. is 0.1 mmH
g or less, and there was no compatibility with the used ink.

The ink used was composed of 60% by weight of water, 38% by weight of diethylene glycol and 2% by weight of a dye, and had a kinematic viscosity of 2.0 mm ² / s, a surface tension of 40 mN / m and a specific gravity of 1.06.

As shown in FIG. 10, the discharging means also serving as a drawing means made of a piezoelectric member is constituted by using a PZT (lead zirconate titanate) piezoelectric member.
When a voltage is applied to the electrodes 40B1 and 40B2 provided on both sides of A, the electrode A is bent and deformed, and the volume inside the head 10 is increased. The ejection means 14 made of a piezoelectric member is composed of a protective layer 44 of silicon oxide having a thickness of 1.0 μm formed by thermally oxidizing a silicon single crystal substrate and an elastic layer made of zirconium oxide having a thickness of 0.8 μm formed by sputtering. Membrane 42
A first electrode 40B1 made of platinum having a thickness of 0.2 μm formed by a sputtering method, a PZT layer 38A having a thickness of 1.0 μm formed by repeating a sol-gel method a plurality of times, and a thickness formed by a sputtering method. The second electrode 40B2 is made of 0.1 μm platinum. The discharging means 14 composed of the piezoelectric member sequentially forms the protective layer 44, the elastic film 42, the first electrode 40B1, and the PZ on the silicon single crystal substrate.
After laminating and forming the T layer 38A and the second electrode 40B2,
It was formed by etching away a silicon single crystal portion. Further, the PZT layer 38A and the second electrode 40B2 can be patterned into a predetermined shape by photoresist and etching, and are formed in a rectangular shape having a width of 400 μm and a length of 1200 μm in this embodiment. The discharging means 14 thus manufactured
To form the wall surface of the ink reservoir,
When a voltage of 20 V is applied between B1 and the second electrode 40B2, a concave bending deformation of at most 2 μm occurs at the center of the wall of the ink reservoir 18 formed by the ejection means 14, and the volume of the ink reservoir increases. did. When the inside of the head 10 was filled with the ink and the ink was drawn in under these conditions, the ink was drawn from the ejection port toward the inside of the head 10 to a position of 25 μm.

The bias applying means 45 was manufactured using an IC circuit, and was arranged on the outer wall of the head 10. Bias applying means 4
In 5, a pull-in potential is applied to the piezoelectric member prior to the discharge signal to cause the discharge means 14 to operate in the pull-in mode. The bias application unit 45 sets the potential applied to the ejection unit 14 to 0 V
To 20 V, and keep applying this potential for a set time. After a potential for pull-in is applied to the ejection unit 14 at 45 steps of bias application, an ejection signal is applied in accordance with an image signal.

Using the head 10 of this embodiment, the state of ejection was observed under magnification. The sealing liquid was disposed in a film shape on the surface of the head 10 where the ejection ports were arranged so as to have a thickness of 20 μm. First, a voltage of 20 V was applied to the piezoelectric member serving as the discharge unit 14 by the bias applying unit 45 to deform the piezoelectric member so as to increase the volume of the discharge chamber 16. Negative pressure was generated by this volume increase, and the sealing liquid in contact with the discharge port was drawn into the discharge port to separate it from the surrounding seal liquid. In this state, the voltage applied to the piezoelectric member, which is the discharging means, is switched from 20 V to 5 V in accordance with the image signal, and the discharge chamber 16 is deformed so as to reduce the volume, and the ink is discharged. 18 was observed to be discharged. After a series of ejections, the bias was released to set the potential to 0 V, and the drawn ink was returned to return to the sealed state.

In the present embodiment, a bias is applied to draw in the seal liquid before the head 10 performs ejection while moving one line (one way by the carriage), and the head 10 moves according to the image signal while moving. Discharge was performed. After the head 10 moves by one line, the bias is released, the drawing is returned, and the head 10 returns to the sealed state. Printing was performed by repeating this series of operations.

In a normal temperature environment, the head 10 of this embodiment is attached to a recording apparatus having a mechanism for feeding recording paper, and an image is printed in a room at normal temperature (temperature: 25 ° C., relative humidity: 50%). Observation of the resulting image with the naked eye revealed that there was no print defect such as blurring and a clear image was recorded.

Further, this recording apparatus is used in a low-temperature environment (temperature
(C, 30% relative humidity) for 24 hours, and a printing test was performed in this low-temperature environment. As a result, clear printing was possible as in the previous test. Observation of the printed image with the naked eye revealed no difference from the printing test at room temperature, and a clear image was recorded.

Further, the ink jet recording head 1
0 was left for 30 days in an environment at a temperature of 25 ° C. and a relative humidity of 30% RH, and then a print test was performed without performing any ordinary maintenance operation of the ink jet recording apparatus to observe an output image. No ejection failure due to clogging occurred in the ink ejection ports, and the printed image had no disturbance of the dots, and a clear image was recorded as before leaving.
A print test was performed after leaving the same head 10 as the recording head 10 of the present embodiment under the same conditions for 30 days except that the seal liquid was not disposed, and clogging occurred in more than half of the discharge ports. And could only be partially printed.

For comparison, a head 10 similar to the head 10 of this embodiment was used except that the ejection means was not driven in the pull-in mode, and a seal liquid having a thickness of 2
It was arranged in a film shape so as to have a thickness of 0 μm. The ejection of the head 10 was observed and adjusted so that a voltage of -16 V was applied to the ejection means for 10 μs and the ejection was performed only at the positive pressure so that the same ejection as that of the head 10 of the example was obtained. The reason why the voltage required for ejection is higher than in the case of the embodiment is that the seal liquid located at the ejection port and the seal liquid located around the ejection port are not separated, so that the voltage around the ejection port is small. It is considered that the ejection is hindered by the sealing liquid located. Further, when this head 10 was attached to a recording apparatus, and a print test of an image was performed in a room at room temperature (air temperature 25 ° C., relative humidity 50%), no significant difference was observed with the naked eye from the print result of the example. . But,
After left for 24 hours in a low-temperature environment (temperature 5 ° C., relative humidity 30%), a printing test was performed in this low-temperature environment. As a result, defective portions where no printing was performed were conspicuous, and only unclear images were obtained. (Second Embodiment) Next, a second embodiment of the present invention will be described. This embodiment has the same configuration as the above-described first embodiment (the various configuration patterns of the first embodiment can be similarly applied to this embodiment). The reference numerals are attached and the description is omitted.

In this embodiment, as shown in FIG. 11, a pull-in signal for driving the discharge means 14 also serving as a pull-in means in a pull-in mode, based on a discharge basic signal and an image signal described later, and an image signal And a signal control means 60 for controlling a discharge signal for driving the discharge means 14 also serving as a drawing means in a discharge mode. The signal control means 60 outputs the pull-in signal to drive the discharge means 14 so as to draw the seal liquid at least before discharging the ink, and then outputs the discharge signal and outputs the discharge signal.
Drive. An ejection cycle in which ink droplets are continuously ejected from the same ejection port 12 from the pull-in to the end of ejection (hereinafter, referred to as “basic ejection cycle” (see FIG. 12))
Do within. The signal control means 60 of the present invention outputs a discharge signal with a predetermined time delay from the pull-in signal so as to discharge the ink after the drawn-in seal liquid is separated from the surrounding seal liquid.

As shown in FIG. 12, the signal control means 60 controls the basic signal (hereinafter referred to as the “basic ejection”) of the ejection frequency (= 1 / basic ejection cycle) when ink droplets are continuously ejected from the same ejection port 12. Signal) and an image signal for selecting ejection / non-ejection when the ink is ejected from the ejection means 14 in accordance with the image information. a (Details will be described later)
Output the delayed ejection signal. In order to output a delayed ejection signal, the signal control means 60 delays the image signal to make an ejection signal, or generates an image signal based on a signal delayed with respect to the ejection basic signal, and sets this as an ejection signal. I do. The delay time a is determined in consideration of design specifications such as the diameter of the discharge unit 14, the discharge port 12, the basic discharge frequency, the thickness of the seal liquid, the kinematic viscosity of the seal liquid, and the surface tension of the seal liquid.
Set the optimal time after the drawn sealing liquid is separated from the surrounding sealing liquid. Further, the delay time a is set so that the ejection is completed by the next pull-in.

It is also preferable that the signal control means 60 variably controls the delay time a of the ejection signal. If variable control is performed based on information on the environment and equipment, control can be performed so as to obtain the optimum delay time depending on the environment and equipment conditions, so that discharge can be performed by selecting conditions under which the same pull-in is performed each time. Further, the ejection is stabilized, and the image quality of the printed image is improved. Signals used as information include signals based on the operating environment such as ink temperature, head surface temperature, temperature inside the printing device, humidity inside the printing device, and atmospheric pressure inside the printing device, the basic ejection frequency, and the setting of the head moving speed during printing. There are a signal based on the setting of the printing apparatus such as a value, a setting value of an image resolution to be printed, and a signal based on a state of the printing apparatus such as a remaining ink amount and a head position during printing.

The signal control means 60 may be arranged on the head as shown in FIG. 11, and as shown in FIG.
It may be arranged in a recording apparatus other than the head, or may be arranged together with an electric circuit for controlling the head and the apparatus.

The signal control means 60 may control a signal applied to, for example, a piezoelectric member constituting the discharge means 14 which also serves as the pull-in means, in order to output the discharge signal delayed as described above. The signal on the way to the discharge means 14 which also functions as the means may be controlled, the discharge basic signal and the image signal may be controlled, and a signal delayed when generating the discharge basic signal and the image signal may be generated and controlled. Is also good. The signal control unit 60 includes a driving circuit of the ejection unit 14 also serving as a pull-in unit, an ejection basic signal generation circuit,
It may be configured to include an image signal generation circuit, a basic clock generation circuit, and the like.

To delay the image signal by the signal control means 60, various known delay circuits are used. For example,
A delay circuit including a capacitor and a resistor, a delay circuit including a plurality of buffer circuits connected in cascade, a delay circuit including a transmission circuit, a counter circuit, and a comparator circuit can be used. The signal control means 60 may be constituted by an IC or an IC circuit.
It is also possible to manufacture a C circuit and the like. Further, it is also possible to perform a delay by converting an input signal into data by a microcomputer control and comparing the data with data on a memory.

When the seal liquid is drawn in for each image signal,
As shown in FIG. 14, the control system according to the present embodiment outputs the ejection basic signal based on the device setting information from the device setting information generating circuit 64 in accordance with the input timing of the clock signal from the basic clock generating circuit 62. In accordance with the input timing of the clock signal from the ejection basic signal generation circuit 66 and the basic clock generation circuit 62, the image information generation circuit 6
An image signal generating circuit 70 for outputting an image signal based on the image information from 8 and a discharge unit 14 serving also as a sealing liquid drawing unit are controlled by a power supply of a drawing unit driving power supply 72 based on the discharge basic signal and the image signal. In addition, the above-mentioned signal control means 60 for controlling the discharge means 14 with the power supply of the discharge means drive power supply 74 is provided. The discharge unit driving power supply 74 may be configured to also serve as the drawing unit driving power supply 72.

The signal control means 60 includes a delay circuit 76 connected to the ejection basic signal generation circuit 66 and the image signal generation circuit 70, and a pull-in means driving power supply 72, the ejection basic signal generation circuit 66, and the image signal generation circuit 70. It has a pull-in means driving circuit 78 connected thereto, and a discharge means driving circuit 80 connected to the delay circuit 76 and the discharge means driving power supply 74.

Next, the operation of the present embodiment will be described.

The signal control means 60 outputs a pull-in signal according to the image signal as shown in FIG. In this method, the seal liquid of the discharge port 12 is drawn on demand only immediately before ink is discharged. Since the retraction is performed only immediately before the ejection, there is no waste in the retraction. When the head 10 having a plurality of ejection ports 12 is used, the retraction can be controlled corresponding to each of the ejection ports 12. Therefore, this method has an advantage that the optimal pull-in control for ejection can be performed for each individual ejection port 12, and high image quality can be achieved.

Then, the signal control means 60 outputs an ejection signal and ejects ink after a delay time a from the input of the image signal. Note that a pull-in signal may be output for each ejection basic signal.

The discharge means 14, which also serves as the pull-in means, operates in the pull-in mode according to the pull-in signal, as shown in FIG. When negative pressure is generated by deformation,
It is set so that the necessary volume can be drawn by adjusting the amount of deformation. That is, as described above, when a piezoelectric member is used for the ejection unit 14, in the pull-in mode, the ink ejection port 12 is used.
The voltage applied to the piezoelectric member changes so as to increase the volume of the first member (first period T1). Further, the amount of pull-in required for separation is appropriately set to an optimum value according to design values such as the diameter of the discharge port 12, the thickness of the seal liquid, the kinematic viscosity of the seal liquid, and the surface tension of the seal liquid. As an example, in the case of a configuration in which the shape of the discharge port does not change the cross-sectional area in the discharge direction,
It is preferable to draw in the sealing liquid at a film pressure or more because the liquid is well separated. Furthermore, the signal control means 60 may variably control the amount of pull-in in response to a case where these conditions change due to the environment or the like.

The discharge means 14, which also serves as the pull-in means, operates in the discharge mode according to the discharge signal, as shown in FIG. In the discharge mode, a positive pressure is applied from the drawn and partitioned state to discharge the ink and the seal liquid drawn into the discharge chamber 16. That is, as described above, the ejection unit 14
When a piezoelectric member is used in the ejection mode, the voltage applied to the piezoelectric member changes so that the volume of the ink ejection port 12 decreases (second period T2). As described above, when a positive pressure is generated by the deformation, the deformation is released from the deformed state of the retracted state to return to the state before the deformation, or the deformation operation is forcibly performed in the reverse direction of the retracted state. Apply pressure. When the piezoelectric member is deformed and discharged, the signal control unit 60 switches the potential applied at the time of pulling in to the reference potential (for example, switches from +10 V to 0 V) or switches to the discharge potential (for example, +10 V to +5 V).
Switch to) to perform the reverse deformation operation of the pull-in. The potential and the rise (or fall) time are appropriately optimized for the diameter of the discharge port 12, the thickness of the seal liquid, the kinematic viscosity of the seal liquid, the surface tension of the seal liquid, the diameter and speed of the ink droplet to be discharged. Choose a time.

The ink jet recording apparatus of the present invention includes an ink discharge port 12, a seal liquid for sealing the ink discharge port 12, and ink discharge means 14 for discharging ink from the ink discharge port 12 in accordance with an image signal. This is an ink jet recording apparatus having an ink ejection unit 14 also serving as a sealing liquid drawing unit for drawing the sealing liquid. With this inkjet recording apparatus, an image is recorded by discharging ink corresponding to an image signal onto an image recording medium. In the ink jet recording apparatus of the present invention, the discharging means 14 which also serves as the drawing means generates a negative pressure at the time of drawing to draw the seal liquid and separates it, and generates a positive pressure at the time of discharging to discharge the ink. Since the pressure can be controlled well, it is preferable to use a method of increasing or decreasing the volume of the discharge chamber 16 to generate the pressure. It is preferable to use a piezoelectric member for the discharging means 14 which also serves as the drawing means, since the behavior of the deformation can be controlled with high accuracy by an electric signal, so that high image quality can be achieved.

The signal control means 60 may be incorporated in the head, or may be arranged outside the head in the recording apparatus. It is also preferable to control the ejection signal variably, because ejection can be performed under more stable conditions according to the environment and the setting and state of the apparatus.

According to the present embodiment, since the signal control means 60 is provided to control the time from drawing in to discharging each time by pulling in each time, it is possible to set so that the state of drawing in is the same every time discharging is performed. . As a result, the state (amount, speed, and the like) of the ejected ink can be made constant every time, and the size of the ink dot to be printed and the variation in the landing position of the ink dot are reduced, thereby improving the image quality of the printed image. Immediately after the retraction, the amplitude of the vibration remaining on the retraction means 24 or the meniscus liquid level may be large. In this case, if the discharge is set after the vibration is sufficiently reduced, the discharge can be performed more stably. .

Furthermore, if the delay time a from the retracting to the discharge is controlled variably on the basis of various conditions, even if the time until the retracted state becomes stable due to environmental fluctuations or the like changes, the retracted state is obtained. Since the ejection can be set after the state becomes the same every time, the ejection is further stabilized, and the image quality of printing is improved. Due to environmental fluctuations, device settings and conditions, etc., the time from retraction to separation and the decay time of vibrations remaining on the seal liquid surface immediately after retraction may change. By selecting and discharging, it is possible to stabilize the operation and effect on the environment and the setting and state of the apparatus.

In the present embodiment, a discharge means 14 which also serves as a pull-in means is provided for each discharge port 12 to perform pull-in and discharge. Therefore, when a plurality of discharge ports 12 are provided, the pull-in can be controlled for each ink discharge of each discharge port 12, so that the sealing liquid can be drawn without loss, and optimal for each discharge port 12. It is also possible to set such that the ejection state is selected and ejected, thereby achieving high image quality.

Further, since the drawing means and the discharging means 14 are configured to serve as the drawing means, the drawing means and the discharging means 14 can be formed and formed on the same substrate at a time. The price can be reduced. Furthermore, since the driving means of the drawing means and the driving means of the discharge means 14 are also used, the size and the price can be reduced.

[0110]

Second Embodiment Hereinafter, the present invention will be described in more detail with reference to a second embodiment, but the present invention is not limited to this.

As shown in FIG. 15, the head has an ink reservoir 18 therein, and an ink discharge means 14 is disposed in a discharge chamber 16 communicating with the discharge port 12 having a diameter of 40 μm. In addition, on the wall surface of the ink reservoir 18, there is disposed an ejection unit 14 also serving as a sealing liquid drawing unit made of a piezoelectric member.

As the sealing liquid, a liquid prepared by mixing a plurality of types of silicone oils (kinematic viscosity: 30 mm ² /
s, surface tension 20.8 mN / m, specific gravity 1.0). The vapor pressure of this sealing liquid at 25 ° C. is 0.1 mmH
g or less, and there was no compatibility with the used ink.

The ink used was composed of 60% by weight of water, 38% by weight of diethylene glycol, and 2% by weight of a dye, and had a kinematic viscosity of 2.0 mm ² / s, a surface tension of 40 mN / m, and a specific gravity of 1.06.

As shown in FIG. 16, the discharge means 14, which also serves as a drawing means made of a piezoelectric member, is constituted by using a PZT (lead zirconate titanate) piezoelectric member.
When a voltage is applied to the electrodes 40B1 and 40B2 provided on both sides of the head 8A, the electrodes 40B1 and 40B2 bend and deform, thereby increasing the volume inside the head. The ejection means 14 made of a piezoelectric member is composed of a protective layer 40 of silicon oxide having a thickness of 1.0 μm formed by thermally oxidizing a silicon single crystal substrate and an elastic layer made of zirconium oxide having a thickness of 0.8 μm formed by sputtering. Membrane 42
A first electrode 40B1 made of platinum having a thickness of 0.2 μm formed by a sputtering method, a PZT layer 38A having a thickness of 1.0 μm formed by repeating a sol-gel method a plurality of times, and a thickness formed by a sputtering method. The second electrode 40B2 is made of 0.1 μm platinum. The discharging means 14 composed of the piezoelectric member sequentially forms the protective layer 44, the elastic film 42, the first electrode 40B1, and the PZ on the silicon single crystal substrate.
After laminating and forming the T layer 38A and the second electrode 40B2,
It was formed by etching away a silicon single crystal portion. In addition, the PZT layer and the second electrode can be patterned into a predetermined shape by photoresist and etching, and are formed in a rectangular shape having a width of 400 μm and a length of 1200 μm in this embodiment. The ejection means 14 thus manufactured is bonded to form a wall surface of the ink reservoir. When a voltage of 20 V is applied between the first electrode 40B1 and the second electrode 40B2, the wall surface of the ink reservoir formed by the ejection means 14 is formed. 2μ at the center
m of the concave deflection deformation occurred, and the volume of the ink reservoir increased. When the inside of the head was filled with ink and the ink was drawn in under these conditions, the ink was drawn from the ejection port 12 toward the inside of the head to a position of 25 μm.

The signal control means 60 was manufactured using an IC circuit and was arranged on the outer wall of the head. In the signal control means 60, a circuit for outputting the ejection signal is configured using a delay circuit. The signal control unit 60 outputs a pull-in signal in accordance with the image signal to drive the discharge unit 14 in the pull-in mode, delays the image signal, outputs a discharge signal after a predetermined time, and drives the discharge unit 14 in the discharge mode. I do. In the pull-in mode, the potential applied to the ejection means 14 was changed from 0 V to 20 V, and in the ejection mode, the potential applied to the ejection means 14 was changed from 20 V to 5 V. The delay time from the input of the image signal to the output of the ejection signal was set to 100 μs. Further, 110 μs after the input of the image signal, the ejection unit 1
4 is returned to 0V.

Using the head of this example, the state of ejection was observed under magnification. The sealing liquid was disposed in a film shape on the surface of the head where the ejection ports 12 were arranged so as to have a thickness of 20 μm. First, an image signal was input to the signal control means 60 to output a pull-in signal, and a voltage of 20 V was applied to the piezoelectric member serving as the discharge means 14 so as to increase the volume of the discharge chamber 16. A negative pressure was generated due to this increase in volume, and the sealing liquid in contact with the discharge port 12 was drawn into the discharge port 12 and separated from the surrounding seal liquid by 100 μs from the input of the image signal. 100 μs after the input of the image signal, the signal control means 60 outputs a discharge signal, switches the voltage applied to the piezoelectric member, which is the discharge means 14, to 5 V, and deforms the discharge chamber 16 so as to reduce the volume, thereby discharging the ink. As a result, it was observed that ink droplets were stably ejected. The ejection means 14 returns to the original state at 110 μs from the input of the image signal, returns the ink of the ejection port 12 to the initial state, and discharges the seal liquid around the ejection port 12 by 500 μs after the operation of the drawing means. The ink at the outlet 12 was returned to the sealed state. When an image signal was input as a continuous pulse and this discharge cycle was repeated at a frequency of 1 kHz, it was observed that the seal liquid was drawn in before every discharge, and that the liquid was stably discharged in that state. Further, when an image signal corresponding to image information is input at a frequency of 1 kHz of the basic ejection signal and ink is ejected, the measurement results of the diameter of the ejected ink droplet and the ejection speed indicate that the image signal is continuous / inconsistent. Regardless of the continuity (that is, the time interval of the ejection), it was observed that the ejection was stable and stable.

In a normal temperature environment, the head of this embodiment is attached to a recording apparatus provided with a mechanism for feeding recording paper, and an image is printed in a room at normal temperature (temperature: 25 ° C., relative humidity: 50%).
When the printed image was observed with the naked eye, there was no printing defect such as blurring, and a clear image was recorded.

Further, this recording apparatus is used in a low-temperature environment (temperature
(C, 30% relative humidity) for 24 hours, and a printing test was performed in this low-temperature environment. As a result, clear printing was possible as in the previous test. Observation of the printed image with the naked eye revealed no difference from the printing test at room temperature, and a clear image was recorded.

Further, after leaving the ink jet recording head in an environment of a temperature of 25 ° C. and a relative humidity of 30% RH for 30 days, a print test was performed without performing any maintenance operation of a normal ink jet recording apparatus, and an output was performed. The image was observed. No ejection failure due to clogging occurred in the ink ejection port 12, and the printed image had no disturbance of dots, and a clear image was recorded as before leaving.
A head similar to the recording head of the present embodiment was left under the same conditions for 30 days except that no seal liquid was disposed,
When a printing test was performed, clogging occurred in more than half of the discharge ports 12, and printing could be performed only partially.

For comparison, a head similar to the head of this embodiment was used except that the discharge means 14 was not driven in the pull-in mode, and a seal liquid having a thickness of 2
It was arranged in a film shape so as to have a thickness of 0 μm. The ejection of this head was observed, and an adjustment was made so that a voltage of -16 V was applied to the ejection means 14 for 10 μs for a period of 10 μs so that the same ejection as the head of the example was obtained, and the ejection was performed only with positive pressure. The reason why the voltage required for ejection is high is that the seal liquid located at the ejection port and the seal liquid located around the ejection port are separated, so that the ejection is hindered by the seal liquid located around the ejection port. It is thought that it is possible. Further, this head is attached to a recording device, and is operated at normal temperature (temperature: 25 ° C.,
When a print test of an image was performed in a room with a relative humidity of 50%), no significant difference was observed with the naked eye from the print result of the example. However, in a low temperature environment (temperature 5 ° C, relative humidity 3)
(0%) for 24 hours, and a printing test was performed in this low-temperature environment. As a result, defective portions where no printing was performed were conspicuous, and only unclear images were obtained.

[0121]

As described above, according to the present invention, since the ink discharging means has the first function of drawing in the sealing liquid and the second function of discharging ink, there are a plurality of ink discharging ports. In such a case, it is possible to perform the drawing of the seal liquid and the discharge of the ink for each discharge port, to perform the drawing of the seal liquid without loss, and to perform the ink discharge in the optimum drawing state for each discharge port. This has the effect of being able to do so.

Further, according to the present invention, by separating (separating) the seal liquid located at the ink discharge port from the seal liquid around the ink discharge port, the seal liquid around the ink discharge port can be separated from the seal liquid. The effect of hindering ink ejection can be eliminated, and thus the resistance during ejection can be reduced. For this reason, even in a low temperature environment in which the viscosity of the sealing liquid increases, a clear image can be printed without causing ejection failure. In addition, since the discharge resistance is low, even if the seal liquid to be arranged is thick or a high-viscosity seal liquid material is selected, both performance against clogging and discharge performance can be achieved, preventing clogging for a longer period of time. Such a head design is also possible. Further, in the embodiment of the present invention, since the ink discharge ports are sealed by the sealing liquid, clogging due to drying of the ink does not occur even after a long period of suspension, so that the discharge operation can be performed immediately when necessary. In addition, the maintenance process after a long-term suspension can be reduced or omitted. For this reason,
In addition to reducing the size and cost of the recording device, it also reduces the waiting time before printing and the noise caused by maintenance, which have been caused by maintenance after a long pause, and suppresses the rise in running costs due to large amounts of ink disposal. This also has the effect that it becomes possible.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a basic configuration of an inkjet recording head according to a first embodiment.

FIG. 2 is an explanatory diagram illustrating a method of generating a negative pressure / positive pressure by a change in the volume of a discharge chamber.

FIG. 3 is a diagram showing a configuration of a head having individual ejection means corresponding to individual ejection ports.

FIG. 4 is a diagram illustrating a configuration using a piezoelectric element as a discharge unit.

FIG. 5 is a diagram illustrating a state in which a sealing liquid is discharged from a discharge port and a sealing state.

FIG. 6 is a diagram illustrating a configuration of a discharge unit that changes an effective area of a piezoelectric member.

FIG. 7 is a diagram showing a configuration of a discharge unit for changing a thickness for applying an electric field.

FIG. 8 is a timing chart according to the first embodiment.

FIG. 9 is a diagram showing the configuration of the first embodiment.

FIG. 10 is a view showing a discharging means (piezoelectric member) in the first embodiment.

FIG. 11 is a cross-sectional view illustrating a basic configuration of an inkjet recording head according to a second embodiment.

FIG. 12 is a timing chart according to the second embodiment.

FIG. 13 is a cross-sectional view illustrating another basic configuration of the inkjet recording head according to the second embodiment.

FIG. 14 is a block diagram of a control system according to the second embodiment.

FIG. 15 is a diagram showing a configuration of a second example.

FIG. 16 is a view showing a discharging means (piezoelectric member) in a second embodiment.

FIGS. 17A and 17B are explanatory diagrams illustrating a method for controlling an area for applying an electric field to a piezoelectric member. FIGS.

FIGS. 18A and 18B are explanatory views illustrating another method for controlling an area for applying an electric field to a piezoelectric member.

FIGS. 19A and 19B are explanatory diagrams illustrating a method of controlling the thickness of a piezoelectric member to which an electric field is applied.

FIGS. 20A and 20B are explanatory views illustrating another method for controlling the thickness of a piezoelectric member to which an electric field is applied.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Head 12 Ink discharge port 14 Discharge means (discharge means also serving as drawing-in means) 16 discharge chamber 18 ink reservoir 22 seal liquid

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Susumu Hirata 430 Green Tech Nakai, Nakai-cho, Ashigara-gun, Kanagawa Fuji Xerox Co., Ltd. Inside (72) Inventor Yuji Suemitsu 430 Green Tech Nakai, Nakaicho, Kanagawa Prefecture, Fuji Xerox Co., Ltd. Within Fuji Xerox Co., Ltd. 72) Inventor Tetsu Mohri 430 Green Tech Nakai, Nakai-cho, Ashigara-gun, Kanagawa Prefecture F-term in Fuji Xerox Co., Ltd.

Claims (25)

[Claims] 1. An ink discharge port for discharging ink, a seal liquid sealing the ink discharge port, a seal liquid of the seal liquid positioned at the ink discharge port, and the ink discharge port of the seal liquid. A first function of drawing the seal liquid into the ink discharge port so that the seal liquid is separated from the seal liquid positioned around the ink discharge port, and a second function of discharging ink from the ink discharge port in response to an input image signal. And an ink discharging unit having the function described above. 2. An ink jet recording head according to claim 1, wherein said ink discharge means changes a volume in a discharge chamber. 3. The ink jetting device according to claim 1, wherein the ink discharging unit includes a piezoelectric member, and executes the first function and the second function by deforming the piezoelectric member. The inkjet recording head according to the above. 4. The ink-jet apparatus according to claim 3, wherein the ink discharge unit controls the area of the piezoelectric member to which an electric field is applied to execute the first function and the second function. Recording head. 5. An electrode provided on at least one side of the piezoelectric member includes a plurality of electrodes having different areas, and the first function and the second function are provided by switching the electrodes and applying an electric field.
5. The ink jet recording head according to claim 3, wherein the ink jet recording head performs the following function. 6. An electrode provided on at least one side of the piezoelectric member is constituted by a plurality of electrodes, and the first function and the second function are performed by changing the number of selected electrodes and applying an electric field. 5. The method according to claim 3, wherein the step is performed.
The inkjet recording head according to the above. 7. The ink discharge means executes the first function and the second function by controlling the thickness of a piezoelectric member to which an electric field is applied in a plurality of superposed piezoelectric members. The ink jet recording head according to claim 3, wherein 8. A structure in which a plurality of piezoelectric members having different thicknesses and electrodes are alternately stacked in the thickness direction of the piezoelectric member, and the first function and the second function are performed by switching the electrodes and applying an electric field. 8. The ink jet recording head according to claim 7, which performs the following function. 9. A structure in which a plurality of piezoelectric members and electrodes are alternately stacked in the thickness direction of the piezoelectric member, and an electric field is applied between the selected pairs of electrodes while changing the number of selected electrode pairs. 8. The ink jet recording head according to claim 7, wherein the first function and the second function are executed by applying the voltage. 10. The apparatus according to claim 1, wherein the ink discharge unit is driven in two modes, a mode for executing the first function and a mode for executing the second function. The inkjet recording head according to any one of the preceding claims. 11. The ink jet recording head according to claim 1, further comprising a holding unit for holding a state in which the sealing liquid is drawn. 12. The inkjet recording according to claim 11, wherein the holding unit holds the drawn-in state by continuing the execution state of the first function when drawing in the sealing liquid. head. 13. The ink discharging device according to claim 11, wherein the ink discharging device discharges the ink a plurality of times when the seal liquid is held in a state of being drawn by the holding device. Inkjet recording head. 14. The ink jet recording head according to claim 11, wherein a state in which the sealing liquid is drawn is released to an original state. 15. A control means for controlling the ink discharge means so that the drawing of the seal liquid and the discharge of the ink are completed within a predetermined discharge basic cycle after outputting the pull-in signal. The inkjet recording head according to any one of claims 1 to 10, wherein: 16. The ink jet recording head according to claim 15, wherein said control means controls said ink discharge means so as to execute discharge of said ink after a predetermined delay time from the output of said pull-in signal. . 17. An ink jet recording head according to claim 16, wherein said control means variably controls said predetermined delay time. 18. The ink jet printer according to claim 15, wherein the control unit controls the ink discharge unit so as to execute the drawing of the seal liquid every time the image signal is input. Item 7. The ink jet recording head according to item 1. 19. The apparatus according to claim 15, wherein said control means controls said ink discharge means to be driven in two modes, a mode for drawing in a seal liquid and a mode for discharging ink. The inkjet recording head according to any one of the preceding claims. 20. An ink jet recording apparatus according to claim 15, wherein said control means controls said ink discharge means so as to draw in the sealing liquid every time before ink discharge. head. 21. Any one of claims 1 to 20
13. An ink jet recording apparatus comprising the ink jet recording head according to item 9. 22. The ink jet recording method for an ink jet recording apparatus according to claim 21, wherein a seal liquid is drawn in at least before ink ejection. 23. The ink jet recording method according to claim 22, wherein a state in which the sealing liquid is drawn is maintained. 24. The ink jet recording method according to claim 23, wherein the ink is ejected a plurality of times while maintaining the state in which the seal liquid is drawn. 25. The ink jet recording method according to claim 22, wherein the sealing liquid is drawn in each time before the ink is ejected.