JPH0671973A - Ink jet recording device - Google Patents

Abstract

PURPOSE:To reduce the cost of a paper feed roller or a resist roller by setting the distance from an ejection outlet face of a recording head to a platen for retaining a recording paper with high accuracy by means of a simple constitution. CONSTITUTION:Feed rollers 3 and 4 and the like for feeding a recording paper 2 to the position of a recording head 5 and a platen 1 as a fixing component guiding the rear face of the recording paper 2 on the recording position are provided, and projections 9 for determining the distance from the ejection outlet face to the platen 1 are formed on both ends outside a recording zone of the platen 1, and the recording head 5 is pressed by the spring energizing force to the projections 9.

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 apparatus for recording by ejecting ink from a recording means onto a recording material.

[0002]

2. Description of the Related Art A recording device having a function of a printer, a copying machine, a facsimile or the like, or a recording device used as an output device such as a composite electronic device including a computer, a word processor or the like, a workstation, etc. Image (including characters etc.) on the recording material (recording medium) such as paper or plastic thin plate based on
Is configured to record. The recording apparatus can be classified into an ink jet type, a wire dot type, a thermal type, a laser beam type, etc., depending on the recording method.

In a serial type recording apparatus which employs a serial scan system in which main scanning is performed in a direction intersecting a conveying direction (sub-scanning direction) of a recording material, the recording material is set at a predetermined recording position and then the recording material is recorded. An image is recorded (main scanning) by a recording unit mounted on a carriage that moves along the material, and a predetermined amount of paper is fed (conveyed material to be recorded) after one line of recording is completed, and then again. The recording of the entire recording material is performed by repeating the operation of recording (main scanning) the image of the next row on the recording material that has stopped. On the other hand, in a line type recording apparatus that records only by sub-scanning in the conveyance direction of the recording material, the recording material is set at a predetermined recording position, and one line of recording is collectively performed while continuously recording paper. Feeding (pitch feeding) is performed to record the entire recording material.

Among the above recording apparatuses, an ink jet type recording apparatus (ink jet recording apparatus) performs recording by ejecting ink from a recording means (recording head) onto a recording material, and the recording means can be made compact. Easy, high-definition images can be recorded at high speed, plain paper can be recorded without special processing, running costs are low, and the non-impact method reduces noise. In addition, it is easy to record a color image using multicolor inks. Among them, the line type using a full multi type recording means in which a large number of ejection openings are arranged in the paper width direction can further speed up recording.

In particular, an ink jet type recording means (recording head) for ejecting ink by utilizing heat energy,
Through the semiconductor manufacturing process such as etching, vapor deposition, and sputtering, the electrothermal converter formed on the substrate, the electrode,
By forming the liquid passage wall, the top plate, and the like, it is possible to easily manufacture a liquid discharge device having a high-density liquid passage arrangement (ejection 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 or processed paper (paper with punched holes for filing, perforated paper, paper of any shape, etc.) has been required to be used.

In the ink jet recording apparatus, from the viewpoint of properly maintaining the position and formation of the ink droplets landing on the recording material to ensure image quality, the ejection port surface of the recording means (recording head) and the recording material. Distance from the recording surface of
It is necessary to keep a constant value. Therefore, in the conventional inkjet recording apparatus, a platen including a rubber roller or the like having a recording unit (image forming unit) is often used, and a recording material is brought into close contact with the platen roller, and the vicinity of the platen is recorded by a recording head. Is taken. In that case, a configuration is adopted in which the sheet distance is determined by abutting the member holding the platen roller and the member holding the recording head. Further, in the ink jet recording apparatus, a recovery operation for maintaining and recovering the ejection performance of the ejection port is usually required, and therefore the recording head itself needs to be moved. On the other hand, it is necessary to position and fix the recording head on or around the circumference of the platen roller whose position is fixed to perform recording on the recording material that is in close contact with the platen.

[0007]

However, in the above-mentioned conventional ink jet recording apparatus, the recording head has to be movably held for the recovery operation, while the platen roller of the platen roller is used for recording. Since it is necessary to position and fix it on the circumference, it is necessary to eliminate rattling between each component for moving the recording head and improve the accuracy of each component itself, and the recording head holding mechanism is complicated and expensive. There is an inconvenience that it becomes something like. Furthermore, since the recording material is pressed against the platen roller, the distance between the recording material and the ejection port surface of the recording head is greatly affected by the runout of the platen roller, the roundness, and the cylindricity. There is also the inconvenience of being easy.

The present invention has been made in view of the above technical problems, and an object of the present invention is to set the distance between the discharge port surface and the recording material with high accuracy with a very simple structure. An object of the present invention is to provide an ink jet recording apparatus which can realize the cost reduction of the transportation means.

[0009]

A feature of the present invention is that a platen having a recording portion is changed from a conventional roller to a fixing member such as a guide plate, and the recording head is abutted on both side portions of the fixing member for positioning. By adopting a structure in which another roller has the function of carrying the recording material, which was performed by the conventional platen roller, the accuracy of the distance between the recording head and the platen is increased, and the cost of the carrying means composed of rollers is reduced. It is a thing.

That is, according to the first aspect of the invention, in an ink jet recording apparatus for recording by ejecting ink from the recording means to the recording material, the recording means and the conveying means for conveying the recording material to the recording portion. The above-described object is achieved by having a configuration including a first guide member that guides the back surface of the recording material and a positioning unit that determines the position of the recording unit with respect to the first guide member. .

According to another aspect of the invention, in addition to the above configuration,
A structure in which the positioning unit is a protrusion provided on both sides of the first guide member, a structure in which the recording unit receives a spring biasing force toward the first guide member, and the first guide member is A configuration that is a flexible member, a configuration in which a second guide member that guides the surface of the recording material is provided between the first guide member and the recording unit, or the second guide member is By adopting a configuration in which the positioning is performed by the first guide member, the above object can be achieved more efficiently.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. 1 is a schematic perspective view showing a main part of a first embodiment of an inkjet recording apparatus to which the present invention is applied, and FIG. 2 is a schematic vertical sectional view of the inkjet recording apparatus of FIG. In FIGS. 1 and 2, 1 is a platen (first guide member) having a recording portion on the upper plane, 2 is a sheet-shaped recording material such as paper or a plastic thin plate, and 3 is a recording material 2 A conveying roller 4 for conveying the recording material 2 to the recording material 2 is pressed against the conveying roller 3 to apply a frictional conveying force to the recording material 2. Reference numeral 5 is a full line type recording means (recording head). A recording material pressing plate (second guide member) for pressing the material 2 near the recording portion (upper surface) of the platen 1, 7 is a head pressing spring for urging the recording head 5 toward the platen 1, 8 Is a guide plate for guiding the recording material 2 on the upstream side of the recording portion.

On the ejection port surface (the surface facing the recording material 2) of the full-line recording head 5, the entire width of the recording material 2 is set so that recording can be performed only by sub-scanning (movement in the carrying direction). The outlets are arranged over the corresponding range. Further, the recording head 5 is movably held in a direction approaching and separating from the platen (first guide member) 1 (vertical direction in the illustrated example). Therefore, both sides of the platen 1 (both sides sandwiching the paper passing range of the recording material 2)
Is provided with a protrusion 9 having a predetermined height. Then, the both ends of the recording head 5 are pressed against these protrusions 9 by the head pressing spring 7, whereby the recording head 5 is pressed.
The distance between the discharge port surface and the platen (first guide member) 1 is kept constant.

The recording head (inkjet head)
Reference numeral 5 is, for example, a multi-head having a density of 16 / mm and about 4,800 discharge ports over the width of A3 size, and the diameter of each discharge port in that case is within 30 microns. The recording head 5 is an inkjet head that ejects ink by using thermal energy, and includes an electrothermal converter for generating thermal energy. Further, the head 5 ejects ink from the ejection port by utilizing the pressure change caused by the growth and contraction of the bubbles due to the film boiling caused by the thermal energy applied by the electrothermal converter.

FIG. 3 is a partial perspective view schematically showing the structure of the ink ejection portion of the recording head 5. In FIG. 3, a plurality of electrothermal converters 52 and wirings corresponding thereto are formed on the substrate 51 of the recording head 5 with the layer of the thin film 53 interposed by the same manufacturing process as a semiconductor (thin film forming method or the like). Are formed. As shown in the drawing, each electrothermal converter 52 is arranged at a position corresponding to each discharge port 59 and liquid path 56. On the substrate 51 (on the thin film 53 on the substrate 51), a liquid path forming member 54 having a plurality of liquid path walls 54A formed in parallel on the lower surface at predetermined intervals is joined. Further, a top plate 55 is joined to the upper surface of the liquid path forming member 54. Although the liquid passage 56 is formed between the liquid passage walls 54A, the liquid passage forming member 54
Are positioned and joined in a positional relationship such that the electrothermal converters 52 are arranged at predetermined positions inside the liquid paths 56.

Each of the liquid passage walls 54A has a predetermined length,
The rear end of each liquid passage 56 has a common liquid chamber 5 formed between the liquid passage forming member 54 and the substrate 51 (or the thin film 53).
It communicates with 7. On the other hand, the other end (tip) of each liquid passage 56 is opened at the ejection port surface (face surface) 58 of the recording head 5, and the ejection port 59 is formed by each opening. Thus, the electrothermal converter 52 such as a heating resistor
The ink jet head 5 is configured so that the ink in the liquid path 56 is film-boiling by energizing (applying a pulse voltage) to the film to heat the film, and the ink droplet is ejected from the ejection port 59 due to the pressure change at that time. . The recording head 5 is mounted such that the arrangement direction of the plurality of ejection ports 59 intersects with the conveyance direction of the recording material (recording paper or the like) 2, and the distance between the ejection port surface 58 and the recording material 2 (paper interval). The distance) is set to about 0.5 to 2.0 mm, for example. Note that FIG.
Further, in the embodiment of FIG. 2, the recording head 5 is attached with its ejection port surface 58 facing downward.

The operation of the ink jet recording apparatus shown in FIGS. 1 to 3 is as follows. First, the recording head 5 in the standby state at a position sufficiently distant from the platen 1 moves to the recording position. At this time, since the recording head 5 can freely move up and down, the left and right positions in FIG. 2 are first determined, and then descend to the platen 1. The platen 1 is provided with the protrusions 9 at both ends outside the recording area of the recording head 5. The height of these protrusions 9 is the distance from the plane of the recording position of the platen 1 to the ejection port surface 58. Are accurately formed so that the value becomes a proper value. Therefore, the recording head 5 that has descended hits the protrusion 9 and the recording head 5 is positioned in the vertical direction. Further, the recording head 5 is fixed by applying a load by the head pressing spring 7.

Next, the recording material 2 is sandwiched between the conveying roller 3 and the pressing roller 4, and is conveyed by the rotation of the conveying roller 3. The recording material 2 that is conveyed advances while being bent along the curvature of the guide plate 8 and the conveyance roller 3, and the recording material pressing plate (second guide member) 6 and the platen (first guide member) 1 Its tip abuts between. At this time, the tip of the recording material 2 is separated from the peripheral surface of the transport roller 3. Therefore, when the recording material 2 passes through the recording material pressing plate 6 and further advances to the recording position, the distance between the recording material 2 and the ejection port surface 58 of the recording head 5 (inter-sheet distance) is , The projection 9 of the platen 1 determines.

According to the above-mentioned embodiment, the recording head 5 is positioned with respect to the recording head and the platen (first guide member) 1.
Since the platen 1 does not rotate like a roller or a belt, the recording head 5
The distance between the platen 1 and the platen 1 can be reliably set with high accuracy without being affected by the accuracy in processing and assembling other members, the uneven rotation, the shake, and the like. Further, in the conventional platen roller, it was necessary to wind a friction member such as rubber around the entire area in the longitudinal direction, but in the above embodiment, the transport roller 3 has a divided structure in which the rollers are arranged only in a predetermined axial range. Since the platen roller is not required to have a higher accuracy than the platen roller, the cost of the transport roller 3 can be reduced.

In the above-described embodiment, the projections 9 for determining the distance between the sheets are provided on both sides of the platen 1.
May be provided on the recording head 5, or may be provided on both the recording head 5 and the platen 1. Alternatively, the platen 1 may be made of a flexible member, the head pressing spring 7 may be omitted, and the recording head 5 may be pressed against the platen 1 to set the sheet-to-sheet distance with high accuracy. Good.

FIG. 4 is a schematic perspective view showing the essential structure of the second embodiment of the ink jet recording apparatus to which the present invention is applied. In this embodiment, the ink jet recording apparatus is a serial type. In FIG. 4, the recording head is mounted on a carriage 11 that can reciprocate in the width direction of the recording material 2, while a guide rail 10 for guiding the movement of the carriage 11 is a platen (made of a flexible member). It is fixed on the first guide member 1). In this case as well, protrusions 9 are provided on both sides of the platen 1, and the guide rails 10 are fixed while being pressed against the upper surfaces of the protrusions 9. When recording, the carriage 11 is pressed against the guide rail 10 from above, so that the distance between sheets can be determined with high accuracy by utilizing the elasticity of the platen 1. The image formation on the recording material 2 is performed by moving the carriage 11 along the guide rail 10 in a pressed state and ejecting ink from the recording head on the carriage 11 in synchronization with this. In the serial scan method as in this embodiment, the ejection port surface of the recording head has a plurality of ejections arranged in a direction perpendicular to the moving direction of the carriage 11 when mounted on the carriage 11. There is an exit.

The second embodiment shown in FIG. 4 is different from the first embodiment shown in FIGS. 1 to 3 in the above points, but has substantially the same structure in other parts, and the corresponding parts are the same. Reference numerals are used, and detailed description thereof is omitted. According to the second embodiment, the sheet-to-paper distance is determined by the projection 9 of the platen 1 and the guide rail 10 fixed thereon, so that the processing of other members is the same as in the case of the first embodiment. Also, it has become possible to set the paper distance with high accuracy and without being affected by the assembling accuracy, uneven rotation, and shake. Further, as in the case of the first embodiment, the carrying roller 3 has only to perform the paper feeding function, so that it is not required to be as accurate as the conventional platen roller.
In addition, since it is possible to have a divided structure in which the rollers are arranged only in a predetermined range in the axial direction, it is possible to reduce the cost of the conveying roller 3.

FIG. 5 is a schematic longitudinal sectional view showing the structure of the essential parts of a third embodiment of an ink jet recording apparatus to which the present invention is applied. In this embodiment, the conveying roller 3 and the pressing roller 4 in the first embodiment shown in FIGS. 1 and 2 are removed, and the recording material 2 is formed by a pair of registration rollers 20 and 21 which are in pressure contact with each other.
The transport means is configured. The registration rollers 20 and 21 correctly correct the leading end of the fed recording material 2 in a direction perpendicular to the conveying direction, and then convey the recording material 2 toward the recording portion. In the present embodiment, the recording material 2 is conveyed to the recording position on the platen 1 only by the conveying force of the registration rollers 20 and 21.

The third embodiment shown in FIG. 5 is different from the first embodiment shown in FIGS. 1 to 3 in the above points, but the other parts have substantially the same structure, and the corresponding parts are the same. Reference numerals are used, and detailed description thereof is omitted. Also in the third embodiment, as in the case of the first embodiment, the positioning of the recording head 5 is performed only by the two parts of the recording head and the platen (first guide member) 1, and the platen 1 Since the sheet does not rotate like a roller or a belt, the sheet-to-sheet distance can be reliably set with high accuracy without being affected by the accuracy of processing and assembling other members, uneven rotation, and shake. Furthermore, in this embodiment,
The registration rollers 20 and 21 as the conveying means are not required to have high accuracy as in the conventional platen roller,
In addition, since it is possible to have a divided structure in which the rollers are arranged only in a predetermined range in the functional axis direction, it is possible to reduce the cost of the conveying means.

In the third embodiment shown in FIG. 5, as in the case of the first embodiment, the projection for determining the inter-sheet distance is the recording head 5 as well.
May be provided on both the platen 1 and the recording head 5. Further, the platen 1 is made of a flexible member, the head pressing spring 7 is omitted, and the recording head 5
The sheet-to-sheet distance may be set with high accuracy by pressing the sheet against the platen 1.

In each of the above-described embodiments, the case of recording with one recording head is illustrated, but the present invention is a color ink jet recording apparatus using a plurality of recording heads for recording with different colors, or with the same color. The present invention can be widely applied regardless of the number of recording heads and recording colors, such as an inkjet recording apparatus for gradation recording using a plurality of recording heads recording with inks having different densities, and the same effect can be obtained. The present invention is also applicable to the case where the recording head and the ink tank are integrated, the case where the recording head and the ink tank are separated, and the like regardless of the arrangement of the recording head and the ink tank. It can be applied and the same effect can be achieved.

The present invention can be applied to an ink jet recording apparatus using a recording means (recording head) using an electromechanical transducer such as a piezo element, but among them, thermal energy is used. In this way, an excellent effect is brought about in an ink jet recording apparatus of the type that ejects ink. This is because such a system can achieve high density recording and high definition recording.

Regarding the typical structure and principle thereof, see, for example, US Pat. Nos. 4,723,129 and 4740.
This is preferably done using the basic principles disclosed in 796. This method can be applied to both the so-called on-demand type and the continuous type, but particularly in the case of the on-demand type, a liquid (ink) is used.
By applying at least one drive signal to the electrothermal converter arranged corresponding to the sheet or liquid path in which is stored, which corresponds to the recorded information and causes a rapid temperature rise exceeding nucleate boiling. , Generates heat energy in the electrothermal converter to cause film boiling on the heat acting surface of the recording means (recording head), and as a result, bubbles can be formed in the liquid (ink) in a one-to-one correspondence with this drive signal. So effective.

By the growth and contraction of the bubbles, the liquid (ink) is ejected through the ejection opening to form at least one droplet. It is more preferable to make the driving signal into a pulse shape because bubbles can be grown and contracted immediately and appropriately, and thus a liquid (ink) with excellent responsiveness can be ejected. As this pulse-shaped drive signal, US Pat.
Those described in US Pat. Nos. 4,633,359 and 4,345,262 are suitable. Incidentally, US Pat. No. 43131 of the invention relating to the rate of temperature rise of the heat acting surface.
If the conditions described in the specification of No. 24 are adopted, more excellent recording can be performed.

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

Further, as described above, the present invention can be effectively applied to a full line type recording head having a length corresponding to the maximum width of a recording material (recording medium) which can be recorded by the recording apparatus. . As such a recording head,
Either a structure that satisfies the length by combining a plurality of recording heads or a structure as one recording head integrally formed may be used. In addition, even with the serial type as in the above example, the recording head fixed to the device main body,
Alternatively, a replaceable chip-type recording head that can be electrically connected to the device body and supply ink from the device body when mounted on the device body, or an ink tank is integrally provided on the recording head itself. The present invention is also effective when the cartridge type recording head described above is used.

Further, it is preferable to add recovery means or preliminary auxiliary means to the recording head provided as a constitution of the recording apparatus in the present invention because the effect of the present invention can be further stabilized. Specific examples thereof include capping means, cleaning means, pressurizing or suctioning means, electrothermal converters or heating elements other than these, or preheating means for the recording head. It is also effective to perform stable recording by performing a preliminary discharge mode in which discharge different from recording is performed.

As described above, regarding the type and number of recording heads mounted, for example, only one is provided corresponding to a single color ink, or a plurality of recording heads having different recording colors and densities are provided. A plurality of inks may be provided corresponding to the ink. That is, for example, 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 either the recording head is integrally configured or a combination of a plurality of recording heads may be used. The present invention is extremely effective for an apparatus provided with at least one of color colors or full colors by color mixing.

In addition, in the above-described embodiments of the present invention, the ink is described as a liquid, but it is an ink that solidifies at room temperature or lower and that softens or liquefies at room temperature, or an ink jet. In the method, the temperature of the ink itself is generally adjusted within a range of 30 ° C. or higher and 70 ° C. or lower to control the temperature of the ink so that the viscosity of the ink is within a stable ejection range. It may be in a liquid form. in addition,
Whether the temperature rise due to thermal energy is positively used as the energy for changing the state of the ink from the solid state to the liquid state, or the ink that solidifies when left standing for the purpose of preventing evaporation of the ink is used. In any case, the ink is liquefied by applying the thermal energy according to the recording signal and the liquid ink is ejected,
The present invention is also applicable to the case of using an ink that has a property of being liquefied only by thermal energy, such as one that has already started to solidify when it reaches the recording medium.

The ink in such a case is described in JP-A-54-54.
As described in JP-A-56847 or JP-A-60-71260, a form in which the electrothermal converter is opposed to a liquid sheet or a solid material held in the recesses or through holes of the porous sheet. 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, as the form of the ink jet recording apparatus according to the present invention, in addition to the one 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, and a facsimile apparatus having a transmitting / receiving function. And the like may be used.

[0037]

As is apparent from the above description, according to the invention of claim 1, in the ink jet recording apparatus for recording by ejecting ink from the recording means to the recording material,
Conveying means for conveying the recording material to the recording portion, first guide member for guiding the back surface of the recording material in the recording portion, and positioning means for determining the position of the recording means with respect to the first guide member. The inkjet recording apparatus is capable of highly accurately setting the distance between the ejection port surface and the recording material with a very simple structure, and can reduce the cost of the transporting means. Provided.

According to another aspect of the present invention, in addition to the above structure, the positioning means is a projection provided on both sides of the first guide member, and the recording means is the first guide. A structure that receives a spring biasing force toward the member,
A configuration in which the first guide member is a flexible member, a configuration in which a second guide member for guiding the surface of the recording material is arranged between the first guide member and the recording unit, or Since the second guide member is positioned by the first guide member, the distance between the ejection port surface and the recording material can be set with high accuracy with a very simple structure, and the conveying means can be used. It is possible to more efficiently provide an inkjet recording apparatus that can reduce the cost.

[Brief description of drawings]

FIG. 1 is a schematic perspective view showing a main part of a first embodiment of an inkjet recording apparatus to which the present invention is applied.

FIG. 2 is a schematic vertical sectional view of a main part of the inkjet recording apparatus of FIG.

FIG. 3 is a partial perspective view schematically showing the structure of an ink ejection portion of the recording means in FIG.

FIG. 4 is a schematic perspective view showing a main part of a second embodiment of an inkjet recording apparatus to which the present invention is applied.

FIG. 5 is a schematic vertical cross-sectional view showing the main parts of a third embodiment of an inkjet recording apparatus to which the present invention has been applied.

[Explanation of symbols]

 1 First Guide Member (Platen) 2 Recording Material 3 Conveying Roller 4 Pressing Roller 5 Recording Means (Recording Head) 6 Second Guide Member (Recording Material Pressing Plate) 7 Head Pressing Spring 8 Guide Plate 9 Protrusion 10 Guide Rail 11 Carriage 20 Registration roller 21 Registration roller 52 Electrothermal converter 56 Liquid path 58 Discharge port surface 59 Discharge port

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Claims (8)

[Claims] 1. In an ink jet recording apparatus for recording by ejecting ink from a recording means to a recording material, a conveying means for conveying the recording material to a recording portion, and a recording portion guiding a back surface of the recording material. And a first guide member for
And a positioning unit that determines the position of the recording unit with respect to the guide member. 2. The ink jet recording apparatus according to claim 1, wherein the positioning unit is a protrusion provided on both sides of the first guide member. 3. The ink jet recording apparatus according to claim 1, wherein the recording unit receives a spring biasing force toward the first guide member. 4. The ink jet recording apparatus according to claim 1, wherein the first guide member is a flexible member. 5. The ink jet recording apparatus according to claim 1, wherein a second guide member for guiding the surface of the recording material is arranged between the first guide member and the recording unit. 6. The ink jet recording apparatus according to claim 5, wherein the second guide member is positioned by the first guide member. 7. The inkjet recording apparatus according to claim 1, wherein the recording means is an inkjet recording means including an electrothermal converter that generates thermal energy used for ejecting ink. 8. The ink jet recording apparatus according to claim 7, wherein the recording unit ejects the ink from the ejection port by utilizing film boiling generated in the ink by the thermal energy generated by the electrothermal converter. .