JP3105364B2 - Ink jet recording head and ink jet recording apparatus - Google Patents

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 and an ink jet recording apparatus for performing recording by discharging ink onto a recording material.

[0002]

2. Description of the Related Art A recording apparatus having functions such as a printer, a copying machine, a facsimile, or a recording apparatus used as an output apparatus such as a composite electronic apparatus including a computer or a word processor, or a workstation is provided with image information (character information, etc.). (Including characters) on a recording material (recording medium) such as paper or a plastic thin plate based on
Is configured to be recorded. The recording apparatus can be classified into an ink jet type, a wire dot type, a thermal type, a laser beam type and the like according to a recording method.

In a serial type recording apparatus employing a recording method in which a main scanning is performed in a direction intersecting a conveying direction (sub-scanning direction) of a recording material such as paper or cloth, the recording material is set at a predetermined recording position. Later, move along the recording material (main scanning)
Image recording or character recording is performed by recording means (recording head) mounted on a carriage to be moved, a predetermined amount of paper is fed (sub-scanning) after one line of recording is completed, and then the next line of image or By repeating the operation of recording (main scanning) characters, images or characters are recorded in a desired range of the recording material. On the other hand, in a line type recording apparatus that performs recording only by sub-scanning in which a recording material is transported in the transport direction, the recording material is set at a predetermined recording position, and recording for one line is continuously performed collectively. By feeding a predetermined amount of paper (pitch feed), an image is recorded on the entire recording material.

Among the above recording apparatuses, an ink jet type recording apparatus (ink jet recording apparatus) performs recording by discharging ink from an ink jet recording means (ink jet recording head) onto a recording material. It can easily record high-definition images at high speed, can record on plain paper without special processing, has low running cost, and has low noise due to non-impact method. In addition, it has an advantage that it is easy to record a color image using multicolor inks. Above all, a line type using a full multi-type recording means in which a large number of discharge ports are arranged in the paper width direction can further increase the recording speed.

[0005] In particular, an ink jet type recording means (recording head) for discharging ink by using thermal energy,
Through a semiconductor manufacturing process such as etching, vapor deposition, sputtering, etc., an electrothermal converter, an electrode,
By forming the liquid path wall, the top plate, and the like, it is possible to easily manufacture a device having a high-density liquid path arrangement (discharge port arrangement), and to further reduce the size. On the other hand, there are various requirements for the material of the recording material,
In recent years, ordinary recording materials such as paper and resin thin plates (OHP
Etc.), thin paper and processed paper (paper with bunch holes or perforated paper for filing, paper of any shape, etc.), cloth, and the like have been required.

In general, in the above-mentioned ink jet recording apparatus, a common liquid chamber communicating with a plurality of discharge ports is provided in a recording head, and ink is supplied to the common liquid chamber from an ink tank by a pump or the like. I have. Also,
A part of the ink supplied to the common liquid chamber is returned to the ink tank. Therefore, the ink tank and the recording head are connected by a supply-side and return-side flow path.

FIG. 9 is a schematic diagram showing an example of an ink supply system to a recording head of a conventional ink jet recording apparatus.
In FIG. 9, a storage tank 71 storing ink and a common liquid chamber 73 of the recording head 72 are connected via a first flow path 74 and a second flow path 75.
4 is connected to a recovery pump 76. A plurality of discharge ports 78 are formed on a surface (discharge port forming surface) 77 of the recording head 72 facing the recording material, and each discharge port 78 communicates with the common liquid chamber 73 via a liquid path. . An electrothermal converter (not shown) for generating thermal energy for discharging ink droplets from the discharge port 78 is disposed in these liquid paths.

The recovery pump 76 discharges bubbles in the ink supply system and thickened and fixed ink in each liquid path,
This is for maintaining the ejection performance. Each of the flow paths 7
The filters 4 and 75 are provided with filters 79 and 80 for capturing dust in the ink. It is effective to dispose these filters near the ink ejection section. In the example of FIG. 9, the filters are provided at the connection portions between the flow paths 74 and 75 and the common liquid chamber 73. By operating the recovery pump 76, the ink in the storage tank (ink tank) 71 is supplied to the common liquid chamber 73 through the first liquid path 74, and the second liquid flows from the common liquid chamber 73 to the second liquid chamber 73. The ink is returned to the ink tank 71 through the path 75.

The method of circulating ink as shown in FIG. 9 is effective for removing air bubbles in each of the flow paths 74 and 75 and the common liquid chamber 73, and in particular, a full line type in which the number of discharge ports 78 is large. Is effective in the case of the ink jet recording head. Further, in the ink supply system of FIG. 9, during the printing operation, the flow resistance of the recovery pump 76 is large.
The ink is supplied from the storage tank 71 into the common liquid chamber 73 through the flow path (return side flow path) 75.

FIG. 10 is a schematic diagram showing another example of the configuration of an ink supply system to a recording head of a conventional ink jet recording apparatus. In this example, a recording sub-tank 81 is provided in addition to the storage tank (main tank) 71, and when the ink amount in the sub-tank 81 falls below a certain value due to ink ejection during recording, the recovery pump 76 removes the ink from the storage tank 71. The sub tank 81 is configured to supply ink.

In FIG. 10, a sub tank 81 is provided at one end of a common liquid chamber 73 of a recording head 72 via a first flow path 74, and the other end of the common liquid chamber 73 is connected to a second liquid path 75. Connected to the sub-tank 81 via the First fluid path 7
4, a recovery pump 76, a recovery rectifying valve 82, and a filter 83 are provided. A filter 84 and a solenoid valve 85 are provided in the second flow path 75. The storage tank (main tank) 71 is provided with a rectifying valve 8 for replenishment.
6, the recovery pump 76 of the first flow path 74
And the recovery rectifying valve 82.

In the ink supply system shown in FIG. 10, the recording operation is performed while the ink in the sub-tank 81 is supplied to the common liquid chamber 73. At the time of the ink ejection recovery operation, the ink is circulated so that each of the flow paths 74 is circulated. , 75 and the air in the common liquid chamber 73, the ink in the first flow path 74 and the ink in the common liquid chamber 73 are returned to the sub-tank 81 by closing the electromagnetic valve 85 and operating the recovery pump 76. Instead, it is also possible to perform a recovery operation of discharging ink from the discharge port 78 to discharge bubbles and thickened ink. In the configuration of FIG. 10, the filters 83 and 84 of the respective flow paths 74 and 75 are provided in the middle of these flow paths. Reference numeral 87 in FIG. 10 indicates an air vent valve of the sub tank 81 for recording.

[0013]

In the ink supply system shown in FIG. 9, the filters 79 and 80 are often attached to the upper surface of the common liquid chamber 73. 9 and 10, the filters 79, 80, 8
Numerals 3 and 84 are for preventing dust from entering the recording head 72 (into the common liquid chamber 73 and the liquid path) from the ink supply system. The smaller the mesh of these filters, the greater the effect. However, as the mesh size of the filter is reduced, the pressure loss of the ink at the time of ejection increases, and the occurrence of ejection failure increases.

For this reason, in order to reduce the pressure loss and to select a filter that does not cause a discharge failure in all the discharge ports, in the case of a recording head having a large number of discharge ports such as a full multi-head, the filter is not used. The required area increases, and as shown in FIG.
In the configuration in which the filter is attached to the (common liquid chamber 73),
There is a disadvantage that the recording head 72 becomes large. In the configuration in which the filter is provided in the middle of the ink flow path as shown in FIG. 10, a filter having a large area can be used relatively easily, but the ink supply pipes (flow paths 74 and 75) are always provided in the recording head 72. Since the recording head 72 needs to be connected, the handling of the recording head 72 becomes inconvenient, and the work during the assembling process of the recording head becomes difficult. With the replaceable type, there is a possibility that dust may enter the head after the head is replaced.

SUMMARY OF THE INVENTION The present invention has been made in view of such technical problems, and an object of the present invention is to reliably prevent clogging of dust in a recording head, and is very compact and easy to handle. An object of the present invention is to provide an ink jet recording means and an ink jet recording apparatus which can be combined at a low cost.

[0016]

In order to achieve the above object, the present invention (claim 1) has an electrothermal transducer, a common liquid chamber, a liquid path, and a discharge port, and discharges ink to a recording material. A first substrate provided with the electrothermal transducer, the common liquid chamber, the liquid path, and the discharge port; a first substrate holding the first substrate and the first substrate; A second substrate having a larger area, a first filter provided at both ends of the first substrate, each of which is connected to the common liquid chamber, and a second filter provided on the second substrate, each of which is provided via the first filter. The second communicating with the common liquid chamber
And a filter, wherein the recording head is connected to an ink supply path for supplying ink for performing recording on the recording material via detachable connection means.

In addition, the present invention provides the first configuration in addition to the above configuration.
The above object can be achieved more efficiently by adopting a configuration in which the mesh of the filter is larger than the mesh of the second filter, or a configuration in which the effective area of the first filter is smaller than the effective area of the second filter.

Another object of the present invention (claim 4) is to provide an ink jet recording apparatus for performing recording by discharging ink from a recording means to a recording material in order to achieve the above object. A first substrate provided with a liquid path and a discharge port, a second substrate holding the first substrate and having a larger area than the first substrate; and a common liquid chamber provided at both ends of the first substrate, respectively. A first filter communicating with the
A printhead having a second filter provided at both ends of the second substrate and communicating with the common liquid chamber via the first filter, an ink tank holding ink to be supplied to the printhead, An ink supply path for supplying the ink in the ink tank to the recording head, wherein the recording head is connected to the ink supply path via detachable connection means. I do.

[0019]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic perspective view showing one embodiment of an ink jet recording apparatus using an ink jet recording head to which the present invention is applied. FIG. 1 shows a case of an ink jet recording apparatus provided with a plurality (four in the illustrated example) of line type ink jet recording heads capable of full color recording. In FIG. 1, reference numerals 1 and 2 denote rollers for holding a recording material 3 such as a sheet of paper or a plastic thin plate and transporting the recording material 3 in a sub-scanning direction (conveying direction) indicated by an arrow F (paper feeding). It is a pair. Reference numerals 4B, 4Y, 4M, and 4C denote full multi-type ink jet recording heads (ink jet recording means) in which discharge ports are arranged over substantially the entire width of the recording material 3. In the following description,
When any one or all of these recording heads are indicated, they are simply indicated by recording heads (recording means) 4.

In the case of full-color recording, for example, black, yellow, magenta, and cyan are used as ink colors ejected from the four recording heads 4. In the illustrated example, four ink jet recording heads 4 are used. They are arranged in this order from the upstream side in the recording material conveyance direction (from below in the figure). Reference numeral 6 denotes a recovery system for preventing ink discharge failure of each recording head 4, which moves between each recording head 4 and the recording material 3 and replaces the recording material 3 during an ejection recovery operation (processing). Then, a recovery operation (recovery process) of the recording head 4 as described later is performed while facing each of the recording heads 4. Also,
Each of the inkjet recording heads 4 includes a head mounting unit 7.
Are mounted with their mutual positional relationship regulated. As described above, the ink jet recording apparatus to which the present invention is applied, that is, the head mounting section 7 for mounting the ink jet recording head 4 and the recording material 3 to the recording position of the recording head 4 mounted on the head mounting section 7. An inkjet recording apparatus having transport means 1 and 2 for transport is configured.

FIG. 2 is a schematic horizontal sectional view showing the configuration of the recording head 4 and the ink supply system in FIG. 1, and FIG. 3 is a vertical sectional view taken along line 3-3 in FIG. 2 and 3, the ink jet recording head 4 has a plurality of ejection ports 8 for ejecting ink, and a liquid path 9 communicating with each ejection port 8.
An electrothermal converter (heating element) 10 which is disposed in each liquid path 9 and generates thermal energy used for discharging ink, and a common liquid chamber for supplying ink to each liquid path 9 11 is provided. The plurality of ejection ports 8 are arranged at a predetermined pitch on the front surface (ejection port forming surface) 22 of the recording head 4.

Then, the respective electrothermal transducers 10 are driven (energized) based on the image signal or the ejection signal, and the thermal energy generated at that time causes the ink in the liquid passage 9 to undergo film boiling. Recording is performed by discharging ink from the corresponding discharge port 8 to the recording material 3 using a change in the state (pressure change or the like). At the time of this printing operation, a predetermined gap (for example, about 0.5 to 1.5 mm) is set between the discharge port forming surface 22 and the recording material 3.

In FIG. 2 and FIG. 3, a storage tank (ink tank) 12 for storing ink can supply ink to the recording head 4 via a first ink supply pipe 13 and a second ink supply pipe 14. It is connected. The first ink supply pipe 13 forms a flow path on the pressure feed side, and a recovery pump 15 is provided in the middle of the flow path. The second ink supply pipe 14 forms a return-side flow path. On the other hand, in the recording head 4, first filters 16 and 17 are provided at both ends of the common liquid chamber 11, and these first filters are disposed on both sides of the recording head 4 by communication paths 18 and 19, respectively. The second filters 20 and 21 are connected.

The first ink supply pipe 13 is connected to one of the second filters 20, and the second ink supply pipe 1
4 is connected to the other second filter 21. Therefore, at the time of the recovery operation, by operating the recovery pump 15, the storage tank 12 → the first ink supply pipe 13 → the recovery pump 15 → the second filter 20 → the communication path 1
8 → the first filter 16 → the ink is supplied (pressurized) to the common liquid chamber 11 through the path of the common liquid chamber 11, and the ink in the common liquid chamber 11 is further returned to the first filter 17 →
The flow is returned into the storage tank 12 through the path of the communication path 19 → the second filter 21 → the second ink supply pipe 14 → the storage tank 12.

That is, at the time of the recovery operation, the ink is circulated through the ink supply pipes 13 and 14 and the common liquid chamber 11 to remove air bubbles and dust inside the recording head 4. By discharging a part of the ink from each discharge port 8, the thickened and fixed ink in each liquid path 9 is also removed. On the other hand, at the time of the recording operation, since the flow path resistance of the recovery pump 15 is large, the ink is supplied into the common liquid chamber 11 through the second ink supply pipe 14.

FIG. 4 is a perspective view showing the structure of an embodiment of the ink jet recording head 4 to which the present invention is applied.
6 is a longitudinal sectional view taken along line 5-5 in FIG. 4, and FIG. 6 is a partial plan sectional view taken along line 6-6 in FIG. Figure 2
In FIG. 6, a plurality of electrothermal transducers (discharge heaters) 10 and wiring of aluminum or the like for supplying power thereto are formed on a first substrate 23 made of a silicon substrate or the like by a film forming technique. . Liquid paths 9 corresponding to the respective electrothermal converters 10 are formed on the first substrate 23 by a solid layer (for example, epoxy resin) 24. And
A top plate 25 is adhered on the solid layer 24. The common liquid chamber 11 for supplying ink to each liquid path 9 is formed by a concave portion inside the top plate 25.

On the first substrate 23, first filter cases 26 and 27 communicating with both ends of the common liquid chamber 11 in the top plate 25 are adhered and fixed. Filters 16 and 17 are inserted. The first substrate 23 is positioned and adhered to a second substrate (base plate of a recording head) 28 and held and fixed on the second substrate. Second filter cases 29 and 30 are fixed to both ends of the second substrate 28, and the second filters 20 and 21 are inserted into these filter cases. Then, at each of both ends, the first filter cases 26 and 27 and the second filter cases 29 and 30 are connected to the communication path 18,
19 are connected.

Each of the second filter cases 29, 30 is connected to the first ink supply pipe 13 and the second ink supply pipe 14 by detachable pipe joints 31, 32 so as to be easily detachable. ing. That is, by connecting each of the pipe joints 31 and 32 to the recording head 4, the ink tank (storage tank) 12 and the recovery pump 15 are connected to the recording head 4, and ink is supplied to the common liquid chamber 11 of the recording head 4. It is configured to be supplied or circulated.

The interior of each of the first filter cases 26 and 27 is housed in the common liquid chamber 11 formed inside the top plate 25.
These first filter cases can be easily connected to both ends of the top plate 25 and have a size that does not protrude from the first substrate 23. The mesh of the first filters 16 and 17 in each of the first filter cases 26 and 27 is selected to have such a size that the pressure loss does not affect the ejection performance even when the ink is ejected from all the ejection ports 8. ing.

The second filter cases 29, 30 and the second filters 20, 21 inside them are provided to prevent dust from entering the common liquid chamber 11 and each liquid passage 9 from the outside (in ink, in the air, etc.). The effect is greater as the mesh of the second filters 20 and 21 is finer, and the area of the second filters 20 and 21 is required to be increased to reduce pressure loss. Therefore, by disposing the second filter cases 29 and 30 in the second substrate 28 having a large area, the second filters 20 and 21 having a large area with a fine mesh can be used. Therefore, in the above embodiment, the mesh of the first filters 16 and 17 is the second filter.
It is selected to be larger than the mesh of the filters 20 and 21,
The effective area of the first filters 16 and 17 is selected to be smaller than the effective area of the second filters 20 and 21.

According to the above embodiment, the first head 25 connected to both ends of the top plate 25 forming the common liquid chamber 11 of the recording head 4 is formed.
The first filter 16, inside the filter cases 26 and 27,
The arrangement of the top plate 17 simplifies the shape of the top plate 25, and eliminates the need for drilling and complicated processing.
Can be determined only by the volume necessary for all ejections. Therefore, the size of the top plate 25 can be reduced, and finally, the size of the first substrate 23 can also be reduced, so that the size and cost of the recording head 4 can be reduced.

Further, during the manufacturing process of the first substrate 23, for example, when the first substrate 23, the solid layer 24, and the top plate 25 are attached, the first filter cases 26, 27 can be attached. The first filters 16 and 17 can prevent dust from entering the common liquid chamber 11 and the liquid path 9 during the manufacturing process. Since this manufacturing process is generally performed in a clean room, it is not necessary to make the meshes of the first filters 16 and 17 very small. Further, when the recording head 4 is used, the first filters 16 and 17 and the second filter 2 are used.
The double filter effect of 0 and 21 makes it possible to completely prevent dust from entering the common liquid chamber 11 and the liquid path 9 from the outside.

FIG. 7 is a perspective view showing the structure of another embodiment of the ink jet recording head 4 to which the present invention is applied, and FIG. 8 is a longitudinal sectional view taken along line 8-8 in FIG. In the present embodiment, as shown in FIGS. 7 and 8, the second filter case 2 containing the second filters 20 and 21 is provided.
Reference numerals 9 and 30 are fixed to the surface of the second substrate 28 opposite to the surface to which the first substrate 23 is bonded. That is, the second filter cases 29 and 39 on both sides are attached to both side portions on the lower surface of the second substrate 28. Then, the first filter cases 26 and 27 and the second filter case 29,
The communication paths 18 and 19 for connecting to the second substrate 30 are vertically penetrated through both ends of the second substrate 28.

The present embodiment is different from the embodiment of FIGS. 4 to 6 in the above points, but has substantially the same configuration in other parts, and corresponding parts are denoted by the same reference numerals. , And detailed description thereof will be omitted. According to the present embodiment,
A second filter case 29 attached to the second substrate 28,
Since the second filter case 30 is disposed on the surface on the opposite side of the first substrate 23, the shape and size of the second filter cases 29 and 30 can be more freely selected. Can be made equal to the length of the first substrate 23. Therefore, according to this embodiment, in addition to obtaining the same effects as those of the above-described embodiment, the effect of preventing dust from clogging in the recording head 4 is further enhanced, and
An effect is obtained that the recording head 4 can be further downsized.

In the above-described embodiment, a case of a line type ink jet recording apparatus using a full line type recording means 4 in which discharge ports 8 are formed over the entire width of the recording area of the recording material 3 will be described as an example. However, the present invention can be similarly applied to a serial type ink jet recording apparatus that moves (main scan) along a recording material by mounting a recording unit on a carriage. A similar effect can be achieved.

In the above-described embodiment, the case of a color ink jet recording apparatus provided with a plurality of recording means for recording in different colors has been exemplified. However, the present invention relates to an ink jet recording apparatus which performs recording with one recording means, Alternatively, the present invention can be similarly applied irrespective of the number or combination of recording means (recording heads) such as an ink jet recording apparatus for gradation recording using a plurality of recording means for recording with the same color and different density inks. Can achieve the same effects. Further, the present invention has a configuration in which a recording head and an ink tank are separately provided and these are connected by an ink supply pipe or the like, and a configuration using a replaceable cartridge type recording unit in which the recording head and the ink tank are integrated. Such,
Regardless of the configuration of the recording head and the ink tank, the present invention can be similarly applied to various ink jet recording apparatuses, and the same effects can be obtained.

The above-described double filter has a great effect particularly in a full-line type recording head in which a large number of ejection ports are arranged so as to correspond to the recordable width of the recording material. For a full line head, about 2000 to 4
Because it has a very large number of outlets of 000,
Even if one ejection port becomes defective due to dust clogging or the like, the entire head also becomes defective, yield is deteriorated, and there is a large cost problem. For this reason, it is necessary to minimize the intrusion of dust into the liquid chamber and the liquid path (discharge section).

The present invention can be applied to an ink jet recording apparatus using, for example, a recording means (recording head) using an electromechanical transducer such as a piezo element. This provides an excellent effect in an ink jet recording apparatus using a recording means of a method of ejecting ink. According to such a method, it is possible to achieve higher density and higher definition of recording.

The typical configuration and principle are described in, for example, US Pat. Nos. 4,723,129 and 4,740.
Preferably, this is done using the basic principles disclosed in US Pat. This method can be applied to both the so-called on-demand type and the continuous type. In particular, in the case of the on-demand type, liquid (ink)
By applying at least one drive signal corresponding to the recorded information and providing a rapid temperature rise exceeding nucleate boiling to an electrothermal transducer arranged corresponding to the sheet or liquid path in which Then, heat energy is generated in the electrothermal transducer, and the film is boiled on the heat acting surface of the recording means (recording head). As a result, air bubbles in the liquid (ink) can be formed in one-to-one correspondence with the driving signal. It is effective.

The liquid (ink) is ejected through the ejection opening by the growth and contraction of the bubble to form at least one droplet. When the drive signal is formed into a pulse shape, the growth and shrinkage of the bubble are performed immediately and appropriately, so that the ejection of a liquid (ink) having particularly excellent responsiveness can be achieved, which is more preferable. As the pulse-shaped drive signal, US Pat.
Those described in 463359 and 4345262 are suitable. In addition, US Pat. No. 4,431,131 of the invention relating to the rate of temperature rise of the heat acting surface.
If the conditions described in the specification of JP-A No. 24 are adopted, more excellent recording can be performed.

As the configuration of the recording head, in addition to the combination of the discharge port, the liquid path, and the electrothermal converter (linear liquid flow path or right-angled liquid flow path) as disclosed in the above-mentioned respective specifications, U.S. Pat. No. 4,558,333 and U.S. Pat. No. 4,558,333 which disclose a configuration in which a heat acting portion is arranged in a bending region.
A configuration using the specification of Japanese Patent No. 459600 is also included in the present invention. In addition, Japanese Unexamined Patent Publication (Kokai) No. 123670/1984 discloses a configuration in which a common slit is used as a discharge portion of an electrothermal converter for a plurality of electrothermal converters, and an aperture for absorbing pressure waves of thermal energy. The present invention is also effective as a configuration based on Japanese Patent Application Laid-Open No. 59-138461, which discloses a configuration corresponding to a discharge unit. That is, according to the present invention, the recording can be reliably and efficiently performed regardless of the form of the recording head.

Further, the full-line type recording head may have a configuration in which the length is satisfied by a combination of a plurality of recording heads, in addition to a configuration in which one recording head is integrally formed. In addition, even with a serial type, a recording head fixed to the apparatus main body, or an exchangeable print head that can be electrically connected to the apparatus main body or supplied with ink from the apparatus main body when attached to the apparatus main body. The present invention is also effective when a chip type recording head or a cartridge type recording head in which an ink tank is provided integrally with the recording head itself is used.

It is preferable to add recovery means or preliminary auxiliary means for the recording head provided as a configuration of the recording apparatus to the present invention since the effects of the present invention can be further stabilized. To be more specific, capping means, cleaning means, pressurizing or sucking means, preheating means using an electrothermal converter or another heating element or a combination thereof for the recording head. Performing a preliminary ejection mode in which ejection is performed separately from printing is also effective for performing stable printing.

As described above, the type and the number of print heads to be mounted are, as described above, one provided for only one color ink, a plurality of print heads having different print colors and densities. The recording mode of the recording apparatus is not limited to the recording mode of only the mainstream color such as black, but may be configured integrally with the recording head. The present invention is also very effective for an apparatus provided with at least one of a multi-color of different colors or a full-color of mixed colors, although any combination of the individual colors may be used.

In addition, in the embodiments of the present invention described above, the ink is described as a liquid. However, an ink which solidifies at room temperature or below and which softens or liquefies at room temperature, or an ink jet ink In general, in the method, the temperature of the ink itself is adjusted within a range of 30 ° C. or more and 70 ° C. or less to control the temperature so that the viscosity of the ink is in a stable ejection range. What is necessary is just to be liquid. in addition,
Whether to positively prevent temperature rise due to thermal energy by using it as energy for changing the state of the ink from a solid state to a liquid state, or use ink that solidifies in a standing state to prevent evaporation of the ink In any case, the ink is liquefied by the application of the heat energy according to the recording signal, and the liquid ink is ejected,
The present invention is also applicable to a case where an ink having a property of being liquefied for the first time by thermal energy, such as one that starts to solidify when it reaches a recording medium, is used.

The ink in such a case is disclosed in
As described in JP-A-56847 or JP-A-60-71260, a form in which the liquid sheet or the solid sheet is opposed to the electrothermal converter while being held as a liquid or solid substance in the concave portion or through hole of the porous sheet. It may be. In the present invention, the most effective one for each of the above-mentioned inks is to execute the above-mentioned film boiling method.

In addition, the form of the ink jet recording apparatus according to the present invention may be used as an image output terminal of an information processing apparatus such as a computer, a copying apparatus combined with a reader or the like, or a facsimile apparatus having a transmission / reception function. And the like.

[0048]

As is apparent from the above description, according to the present invention (claim 1), it has an electrothermal converter, a common liquid chamber, a liquid path, and a discharge port, and discharges ink to a recording material. A first substrate provided with the electrothermal transducer, the common liquid chamber, the liquid path, and the discharge port; a first substrate holding the first substrate and the first substrate; A second substrate having a larger area, a first filter provided at both ends of the first substrate, each of which is connected to the common liquid chamber, and a second filter provided on the second substrate, each of which is provided via the first filter. A second filter communicating with a common liquid chamber, wherein the recording head is connected to an ink supply path for supplying ink for performing recording on the recording material via detachable connection means. Record When handling head alone, in addition to being able to completely prevent dust from entering from the outside by a double filter effect into the common liquid chamber and liquid passages, the first
By providing the second filter communicating with the common liquid chamber via the filter on the second substrate holding the first substrate and having a larger area than the first substrate, a second filter having a large area with a fine mesh is provided. It is possible to freely select the shape and size of the second filter according to the use, for example, it can be used. Further, by providing the second filter and the first substrate on the second substrate,
There is provided an ink jet recording head which enables the recording head to be very compact, easy to handle, and inexpensive.

According to the present invention, in addition to the above configuration, a configuration in which the mesh of the first filter is larger than the mesh of the second filter, or the effective area of the first filter is made smaller than the effective area of the second filter. With this configuration, an ink jet recording unit that can achieve the above-described effects more efficiently is provided.

According to another aspect of the present invention (claim 4), in an ink jet recording apparatus for performing recording by discharging ink from a recording means to a recording material, an electrothermal transducer, a common liquid chamber, a liquid path, and a discharge port. A first substrate provided with a first substrate, a second substrate holding the first substrate and having a larger area than the first substrate, and a first substrate provided at both ends of the first substrate and communicating with the common liquid chamber. A recording head having a filter, and second filters provided at both ends of the second substrate and communicating with the common liquid chamber via the first filter, respectively, and ink holding ink to be supplied to the recording head A tank, and an ink supply path for supplying ink in the ink tank to the recording head, wherein the recording head is connected to the ink supply path via detachable connection means. When the recording head is handled as a single unit, it is possible to completely prevent dust from entering the common liquid chamber and the liquid path from the outside by the double filter effect, By providing the second filter communicating with the common liquid chamber on the second substrate that holds the first substrate and has a larger area than the first substrate,
It is possible to freely select the shape and size of the second filter according to the application, for example, a fine mesh having a large area with a fine mesh can be used as the second filter. By providing the second filter and the first substrate, there is provided an ink jet recording apparatus in which the recording head is very compact, easy to handle, and can be integrated at low cost.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view of an embodiment of an ink jet recording apparatus having an ink jet recording head to which the present invention is applied.

FIG. 2 is a schematic plan view of one embodiment of an ink supply system of the ink jet recording apparatus to which the present invention is applied.

FIG. 3 is a schematic partial longitudinal sectional view taken along line 3-3 in FIG. 2;

FIG. 4 is a schematic perspective view of one embodiment of an ink jet recording head to which the present invention is applied.

FIG. 5 is a schematic longitudinal sectional view taken along line 5-5 in FIG.

6 is a schematic plan sectional view taken along line 6-6 in FIG.

FIG. 7 is a schematic perspective view of another embodiment of the ink jet recording head to which the present invention is applied.

8 is a schematic longitudinal sectional view taken along line 8-8 in FIG.

FIG. 9 is a schematic diagram illustrating an example of an ink supply system of a conventional inkjet recording apparatus.

FIG. 10 is a schematic diagram illustrating another example of an ink supply system of a conventional inkjet recording apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Conveying roller pair 2 Conveying roller pair 3 Recording material 4 Recording means (recording head) 6 Recovery system 7 Head mounting part 8 Discharge port 9 Liquid path 10 Electrothermal converter 11 Common liquid chamber 12 Storage tank (main tank) 13th 1 ink supply pipe 14 second ink supply pipe 15 recovery pump 16 first filter 17 first filter 18 communication path 19 communication path 20 second filter 21 second filter 22 ejection port forming surface 23 first substrate 24 solid layer 25 Top plate 26 First filter case 27 First filter case 28 Second substrate 29 Second filter case 30 Second filter case 31 Pipe joint 32 Pipe joint

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Torachika Nagata 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (56) References JP-A-4-212864 (JP, A) JP-A-Hei. 5-50610 (JP, A) JP-A-3-234652 (JP, A) JP-A-4-211962 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B41J 2/175 B41J 2/05

Claims (6)

(57) [Claims] 1. An ink jet recording head having an electrothermal transducer, a common liquid chamber, a liquid path, and a discharge port for performing recording by discharging ink to a recording material, wherein the electrothermal transducer and the common A first substrate provided with a liquid chamber, the liquid path, and the discharge port; a second substrate holding the first substrate and having a larger area than the first substrate; and a second substrate provided at both ends of the first substrate. A first filter that communicates with the common liquid chamber, and a second filter that is provided on the second substrate and communicates with the common liquid chamber via the first filter, respectively. An ink jet recording head connected to an ink supply path for supplying ink for performing recording on the recording material via detachable connection means. 2. The method of claim 1, wherein the mesh of the first filter is larger than the mesh of the second filter.
Inkjet recording head. 3. The effective area of the first filter is smaller than the effective area of the second filter.
Inkjet recording head. 4. An ink jet recording apparatus for performing recording by discharging ink from a recording means to a recording material, comprising: a first substrate provided with an electrothermal transducer, a common liquid chamber, a liquid path, and a discharge port; A second substrate holding one substrate and having a larger area than the first substrate; first filters provided at both ends of the first substrate and communicating with the common liquid chamber, respectively; A print head provided with a second filter that communicates with the common liquid chamber via the first filter, an ink tank that holds ink to be supplied to the print head, and an ink tank that holds the ink in the ink tank. An ink supply path for supplying the ink to the recording head, wherein the recording head is connected to the ink supply path via detachable connection means. Jet recording apparatus. 5. The ink jet recording apparatus according to claim 4, wherein said recording head is an ink jet recording head including an electrothermal transducer for generating thermal energy used for discharging ink. 6. The ink jet recording apparatus according to claim 5, wherein the recording head discharges the ink from a discharge port using film boiling generated in the ink by thermal energy generated by the electrothermal transducer. .