JP2761671B2 - Ink jet recording device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording apparatus that performs recording by discharging ink from a recording unit onto a recording material.

[Conventional technology]

2. Description of the Related Art Recording devices such as printers, copiers, and facsimile machines are configured to form an image on a recording material such as paper or a thin plastic plate based on image information.

The recording device 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. Among them, the ink jet type (ink jet recording device) discharges ink from a recording head onto a recording material. It is configured to perform recording.

Inkjet recording devices can record high-definition images at high speeds, and are non-impact systems, so there is little noise, and it is easy to record color images using multicolor inks. Has advantages.

In this ink jet recording apparatus, there is a case where the recorded ink on the recording material does not dry naturally or is difficult to dry. In consideration of such a case, the recording end portion of the recording material is forcibly set. It has been practiced to provide a drying and fixing device such as a hot air fan for drying.

[Technical problem to be solved by the invention]

In the conventional fixing method, the driving conditions of the fixing device, the conveyance speed of the recording material, and the amount of ink applied are adjusted so that the ink drying and fixing effect is uniform over the entire area of the recording material.

Therefore, in an environment where it is difficult to dry and fix, such as low temperature and high humidity, there is a technical problem that the dry fixing effect of the rear end portion of the recording material tends to be insufficient.

In other words, at the rear end portion of the recording material, before the drying time for leaving after passing through the drying / fixing unit is not sufficiently given,
Since it is touched by the user's hand, there is a possibility that the recorded image may be disturbed or the user's hand may become dirty.

Therefore, conventionally, fixing conditions have been generally set such that the rear end portion of the recording material is sufficiently dried.

However, in such a setting method, it is necessary to increase the driving energy of the fixing device, and the size and size of the fixing device are increased, the selection range of components is reduced, and the cost and size of the apparatus body are increased. There was a technical problem of inviting.

In addition, the recording material transport system for recording and fixing is independent,
Although it is conceivable to set the transport speed so that the fixing device staying time at the rear end portion of the recording material becomes longer, such a method increases the complexity of the transport system and the size of the apparatus main body, resulting in cost reduction. There was a technical problem of becoming too expensive.

That is, in an ink jet recording apparatus equipped with a conventional fixing device, the driving conditions of the fixing device, the conveyance speed of the recording material, and the ink ejection so as to make the effect of drying and fixing the ink on the recorded recording material uniform. Because the amount and the like are set, it has not been possible to provide an ink jet recording apparatus that can sufficiently dry the rear end portion of the recording material and can be configured to be small and inexpensive.

The present invention has been made in view of such technical problems, and an object of the present invention is to suppress energy consumption and to reliably perform ink fixing over the entire area including a rear end portion of a recording material. An object of the present invention is to provide an ink jet recording apparatus.

[Means for solving the problem]

The present invention is directed to an ink jet recording apparatus that performs recording by discharging ink from a recording unit to a recording material, and a fixing unit for fixing the recorded recording material ink.
A driving condition switching unit for changing a driving condition of the fixing unit; and a rear end portion detecting unit for detecting a rear end portion of the recording material, wherein the rear end portion of the recording material passes through the fixing unit. By detecting the timing, the driving conditions of the fixing unit at the timing are switched by the driving condition switching unit so as to enhance the fixing effect, so that energy consumption is suppressed and the rear end portion of the recording material is suppressed. It is intended to provide an ink jet recording apparatus capable of reliably performing ink fixing over the entire area including the above.

〔Example〕

 Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a longitudinal sectional view schematically showing a configuration of one embodiment of an ink jet recording apparatus according to the present invention.

In FIG. 1, reference numeral 1 denotes a recording material
A recording means (recording head) for performing recording on the recording medium 2 passes through a facing portion (lower side in the drawing) of the recording means 1.
A transport roller unit composed of a pair of rollers for transporting
Reference numeral 3 denotes a first paper discharge roller unit composed of a pair of rollers. Reference numeral 4 denotes a paper discharge roller unit of FIG. 2 composed of a pair of rollers for discharging the recording material 7 on which recording has been performed. A drying / fixing device comprising a hot air fan for drying ink on a material, in which a blowing port 5a is inclined so as to blow hot air toward the conveying direction of the recording material 7 (direction of arrow a). Is provided.

Reference numeral 6 denotes a recording material support member for supporting the back surface of the recording material 7 between the first discharge roller unit 3 and the second discharge roller unit 4, and faces the fixing device 5. It is provided.

In addition, 16 is a cassette which stores the recording material 7,
The recording material 7 stored in the cassette 16 is sent to a recording position by a feed roller 18.

 Reference numeral 17 denotes a paper discharge tray.

Here, in the present embodiment, a rear end portion detecting means 8 including a light emitting element 8A and a light receiving element 8B for detecting the rear end of the recording material 7 is provided upstream of the conveying roller unit 2 in the paper feeding direction.
Are arranged.

Then, the detection signal from the rear end portion detecting means 8 and the fixing device driving condition switching device 9 are incorporated so that the driving condition of the fixing device 5 can be changed by the switching device 9.

The recording head 1 is an ink jet recording head that discharges ink using thermal energy,
It has an electrothermal converter for generating thermal energy.

The recording head 1 performs recording by discharging ink from a discharge port using a pressure change generated by growth and shrinkage of bubbles caused by film boiling caused by thermal energy applied by the electrothermal transducer. It is.

FIG. 2 is a partial perspective view schematically showing the configuration of the ink ejection section of the recording head 1 in FIG.

In FIG. 2, a thin film is formed on a substrate 21 of the recording head 1.
A plurality of electrothermal converters 22 and wirings corresponding thereto are formed by the same manufacturing process (thin film forming method, etc.) as that of the semiconductor with the 23 layers interposed.

As shown, the electrothermal transducers 22 are arranged at positions corresponding to respective discharge ports and liquid paths described later.

On the substrate 21 (on the thin film 23 on the substrate 21), a liquid path forming member 24 having a plurality of liquid path walls 24A formed in parallel on a lower surface at predetermined intervals is joined.

Further, a top plate 25 is joined to the upper surface of the liquid path forming member 24.

The liquid passage 26 is formed between the liquid passage walls 24A, and the liquid passage forming member 24 is positioned at such a position that the electrothermal transducers 22 are arranged at predetermined positions inside the liquid passages 26. Positioned and joined in relation.

Each of the liquid path walls 24A has a predetermined length, and the rear end of each of the liquid paths 26 is connected to the liquid path forming member 24 and the substrate 21 (or the thin film 2).
3) and penetrates into the common liquid chamber 27 formed between them.

On the other hand, the other end (tip) of each liquid path 26 is opened as a discharge port 29 on a discharge port surface (face surface) 28 of the recording head 1.

In this way, by energizing (applying a pulse voltage) the electrothermal transducer 22 such as a heating resistor to generate heat, the ink in the liquid passage 26 is film-boiled. An ink jet recording head for discharging droplets is configured.

FIG. 3 is a functional block diagram showing a schematic functional configuration of a control unit relating to the fixing device driving condition switching device 9. As shown in FIG.

In FIG. 3, the fixing device driving condition switching device 9 includes:
For example, a CPU 101 such as a microprocessor, a ROM 102 storing a control program and various data of the CPU shown in the flowchart of FIG. 4, and a RAM 1 used as a work area of the CPU 101 and temporarily storing various data.
03 and so on.

To the CPU 101, a detection signal from a rear end portion detecting means 8 for detecting the rear end of the recording material 7 is input.

When the rear end portion detection signal is input to the CPU 101, a predetermined driving condition is read out from the fixing device driving condition table 104, and the fixing device driver 105 is controlled based on the driving condition to drive the fixing device 5. It is configured to be.

The operation of each part of the ink jet recording apparatus according to the present embodiment is as follows.

The recording material 7 is conveyed in the direction of the arrow while giving an appropriate tension by the conveyance roller unit 2 and the first paper discharge roller unit 3, and an image is recorded by ink ejected from the recording head 1 during that time.

The recording material 7 that has passed through the first paper discharge roller unit 3 is supported by the recording material support member 6 while the second paper discharge roller unit 4
In the meantime, hot air is blown from a hot air fan fixing device (dry fixing device) 5 composed of a heater and a flow-through fan, and the recorded ink on the recording material is dried and fixed.

When the recording material 7 is conveyed by a predetermined amount and the trailing end portion detecting device 8 detects the rear end of the recording material 7, a switching signal is sent from the detecting device 8 to the fixing device driving condition switching device 9.

Upon receiving the switching signal, the driving condition switching device 9 is switched to drive under the drying fixing device driving conditions set in advance so as to enhance the drying and fixing.

At this time, when the hot air fan 5 is used as the drying and fixing device as in the present embodiment, the drying and fixing conditions are increased by increasing the heater temperature or increasing the fan wind speed while keeping the heater temperature constant. be able to.

In this way, the recording material 7
By increasing the fixing effect at the rear end portion, it is possible to perform reliable dry fixing over the entire area of the recording material 7.

FIG. 4 is a flowchart showing an operation sequence of the above-described fixing device driving condition switching device 9.

In FIG. 4, when the fixing device 5 is started in step S1 in response to a fixing device start command, it is determined in step S2 whether or not there is a signal from the rear end portion detecting means 8 (rear end portion detection signal).

If there is no rear end portion detection signal, the fixing device driving conditions are fixed as they are in step S3.

When the rear end portion detection signal is issued, the process proceeds to step S4, and the driving condition of the fixing device is switched so that the fixing effect becomes high.

Next, in step S5, it is determined whether or not the recording material 7 has been discharged from the fixing device 5.

Until the recording material 7 is discharged, the fixing device 5 is driven under a condition with a high fixing effect.
Proceeding to S6, the driving of the fixing device 5 is stopped.

Next, experimental results regarding the drying and fixing conditions described above will be described.

In this experiment, an ink jet head of an ink jet printer BJC430 manufactured by Canon Inc. was used as the recording head 1, an ink of the same BJC430 (water-based ink containing a non-volatile solvent) was used as the ink, and a recording material 7 having a thickness of 75 μm was used. 10μ thick PVA resin on one side of PET film
Those coated with m were used.

The drying and fixing device 5 includes a once-through fan having a diameter of 30 mm.
By using a combination of 5c and a nichrome wire heating element 5b, the once-through fan 5c was driven at 1,000 revolutions per minute.

This experiment was performed in an environment at a room temperature of 23 ° C. and a humidity of 60%.

First, when the conveyance speed of the recording material 7 at the time of recording is 5 mm / sec, and the power consumption of the nichrome wire heating element 5b is fixed at 100 W, when the rear end of the recording material 7 is touched immediately after being discharged to the tray 17, The image was disturbed and ink adhered to the hand.

Next, an experiment was conducted by applying the above-described embodiment using the present invention.

That is, while the length of the rear end portion of the recording material 7 of 50 mm passes through the fixing device 5, the driving voltage is switched so that the rotation speed of the flow-through fan 5c of the fixing device 5 is increased to 3000 rotations per minute to reduce the wind speed. Increased.

Then, even if any part of the recording material 7 immediately after being discharged to the tray 17 was touched, a recorded matter without disturbance of an image or ink adhesion to a hand was obtained.

In this way, the power consumption when this embodiment is applied is about half that in the case where the once-through fan is driven at 3000 revolutions per minute over the entire area.

Further, since the driving time for high-speed rotation can be shortened, the degree of freedom in selecting a fan including a driving system is expanded, and the size and cost of the recording apparatus can be reduced.

FIG. 5 is a schematic diagram showing the configuration of an ink jet recording apparatus according to another embodiment of the present invention.

In FIG. 5, reference numeral 1 denotes a recording material 7 by discharging ink.
A recording head 2 for performing recording on the recording head 2, a transport roller unit composed of a pair of rollers for transporting the recording material 7 through a facing portion (the lower side in the drawing) of the recording head 1, and 3 composed of a pair of rollers The first paper discharge roller section 4 is a second paper discharge roller section composed of a pair of rollers for discharging the recorded recording material 7, and these are substantially the same as those in FIG. is there.

Therefore, in the present embodiment, the first discharge roller unit 3
A drying / fixing unit 10 composed of a backside heating plate is provided between the second fixing unit 10 and the second sheet discharging roller unit 4.

The backside heating plate 10 includes a plate member 11 having good heat conductivity and a heating element 12 joined to the plate member in a thermally coupled state.

The recording material 7 is heated by the first paper discharge roller unit 3 and the second paper discharge roller unit 4 by the backside heating plate 10 (plate-like member 11).
Transported in close contact with

Therefore, the recorded recording material 7 is heated from the back while being conveyed, and the recording ink is dried and fixed.

In FIG. 5, reference numeral 13 denotes a counter control device which receives an input signal of a pulse motor (not shown) for driving the transport roller unit 2, and reference numeral 14 denotes a driving condition switching device for switching a drying / fixing device driving condition. It is.

Therefore, in the present embodiment, the counter control device 13 and the drying / fixing driving condition switching device 14 are configured so that the driving conditions of the rear heating plate (dry fixing device) 10 can be switched and controlled.

FIG. 6 is a functional block diagram showing a schematic functional configuration of a control system of the fixing device 10 in the recording apparatus of FIG.

In FIG. 6, a counter control device 13 is used as a work area for a counter 110, for example, a CPU 111 such as a microprocessor, a ROM 112 storing a control program and various data of the CPU shown in the flowchart of FIG. And a RAM 113 for temporarily storing various data.

The counter 110 counts the number of pulses according to the amount of conveyance of the recording material 7 from the time of feeding.

The counter control device 13 sends a signal to the fixing device drive condition switching device 14 when the counter 110 counts a preset number of pulses.

The driving condition switching device 14 is configured to, upon receiving the signal, switch the driving condition of the fixing device (backside heating plate) 10 to a preset condition so as to increase the dry fixing condition.

The operation of each part of the ink jet recording apparatus according to the present embodiment is as follows.

The recording material 7 is conveyed in the direction of the arrow while giving an appropriate tension by the conveyance roller unit 2 and the first paper discharge roller unit 3, and an image is recorded by ink ejected from the recording head 1 during that time.

The recording material 7 that has passed through the first paper discharge roller unit 3 reaches the second paper discharge roller unit 4 while being supported by the backside heating plate 10, while the recording surface is moved by the backside heating plate 10. Dry fixing of the above ink is performed.

The counter control device 13 starts operating when the recording material 7 is fed, continues the operation while the recording material 7 is being conveyed, and counts the number of pulses corresponding to the transport amount of the recording material 7.

Therefore, when the counter control device 13 counts a preset number of pulses (time required for the desired rear end portion of the recording material 7 to reach the heating plate 10), the counter control device 13 sends a signal to the drying / fixing unit driving condition switching device 14 Send.

Upon receiving the signal, the drive condition switching device 14 switches the drive condition of the backside heating plate 10 to a preset condition so as to increase the dry fixing condition.

When a rear heating plate is used as the drying and fixing device 10 as in this embodiment, the voltage applied to the heating element 12 is increased, and the amount of heat generation is increased to increase the heating element temperature, thereby increasing the conditions for dry fixing. Can be.

Therefore, the rear end portion of the recording material 7 on which the signal generation time of the counter control device 13 is recorded is determined by the rear heating plate 10.
, The dry fixing effect at the rear end of the recording material 7 can be enhanced.

Thus, by increasing the fixing effect at the rear end portion of the recording material 7, it is possible to perform reliable dry fixing over the entire area of the recording material 7.

FIG. 7 is a flowchart showing a sequence of the control operation of the fixing device 10 described above.

In FIG. 7, the step of issuing a paper feed signal
The counter 110 is started in S101, and the fixing device 10 is started in step S102.

Therefore, it is determined whether or not the count value of the counter 110 has reached the set value in step S103.

If the set value has not yet been reached, the driving conditions of the fixing device 10 are fixed as they are in step S104.

When the count value has reached the set value, the process proceeds to step S105, and the driving conditions of the fixing device are switched so that the fixing effect becomes high.

Next, in step S106, it is determined whether or not the recording material 7 has been discharged from the fixing cutoff 10.

Until the recording material 7 is discharged, the fixing device 10 is driven under a condition with a high fixing effect.
Proceeding to S107, the driving of the fixing device 10 is stopped.

Next, experimental results regarding the drying and fixing conditions will be described.

In this experiment, as in the experiment of the above-described embodiment, the inkjet head of the inkjet printer BJC430 manufactured by Canon Inc. was used as the recording head 1, and the ink of the same BJC430 (water-based ink containing a non-volatile solvent) was used as the ink. And a 75 μm thick PET as the recording material 7.
A film coated on one side with a PVA resin having a thickness of 10 μm was used.

Therefore, first, an experiment was performed with the conveyance speed of the recording material 7 fixed at 5 mm / sec and the surface temperature of the backside heating plate 10 fixed at 80 ° C.

Under this condition, fixing was performed without any problem when the room temperature was set to 23 ° C. and the humidity was set to 50%. However, when the humidity alone was increased to 80%, when the recording material 7 was touched immediately after discharge, the trailing edge Incomplete fixing of the length of about 40 mm caused a problem that ink adhered to the hand and the image was disturbed.

Therefore, an experiment was conducted by applying the above-described embodiment using the present invention.

That is, the timing when the rear end 40 mm portion of the recording material 7 passes through the fixing device 10 is detected by the counter control device 13, and the driving voltage of the heater 12 is switched by the drying fixing device driving condition switching device 14. The surface temperature was adjusted to 110 ° C.

Then, even in an environment of room temperature 23 ° C. and humidity 80%, the recording material 7
Was completely fixed over the entire area.

In this way, the power consumption when this embodiment is applied can be reduced by about 30% compared to the case where the temperature of the entire area of the recording material 7 is adjusted to 110 ° C., and energy saving can be achieved. .

In addition, the time required to reach the reference temperature control temperature (80 ° C. in this experiment), that is, the waiting time, could be reduced by about 40% compared to the case where the reference temperature control temperature was set to 110 ° C. .

Furthermore, since the time for maintaining the temperature at a high temperature (110 ° C. in this experiment) can be shortened, the degree of freedom in selecting the material of the heater 13 is increased, and the size and cost of the recording apparatus can be reduced. Was.

In each of the above embodiments, a heating / drying fixing unit (hot air fan, backside heating plate) is used as the fixing unit, an optical unit or a counter control unit is used as the trailing end detecting unit, and the driving condition switching is performed. Although means for switching the wind speed or heater temperature was used as the means, the present invention
The invention is not limited to these means, and other means can be used as long as they have the same function and effect.

Further, in each of the above-described experiments, a specific coated paper was used as the recording material 7. However, the present invention is applied to a recording medium having a problem in fixing property such as recording on plain paper (PPC paper) or cloth or resin. As long as recording is performed on a recording material, the present invention can be applied to the case where recording is performed on any type of recording material, and the same operation and effect can be achieved.

According to the above-described embodiment, the driving conditions of the fixing units 5 and 10 are switched so that the fixing effect of the rear end portion of the recording material 7 on which recording is performed is enhanced. As a result, an ink jet recording apparatus capable of reliably performing fixing over the entire area including the rear end portion of the recording material 7 and achieving reduction in size and cost of the fixing device was obtained.

In the present invention, a serial recording method in which the recording head 1 is moved along the recording material 7 to perform scanning recording, or a recording head having a length corresponding to the width of the recording area of the recording material 7 is used. The present invention can be applied irrespective of the type of recording system such as the line recording system, and can achieve the same effect.

The recording head 1 is a replaceable cartridge type in which an ink discharge unit and an ink tank are integrated, and a type in which the ink discharge unit and the ink tank are separated from each other, for example, are coupled via a coupler and a tube. Any type of recording head can be used, such as a recording head or a type of recording head having only a head portion having no ink tank, and similar effects can be achieved.

Further, in the above embodiment, the case where one recording head 1 is used has been exemplified. However, the present invention is applicable to the case where a plurality of recording heads having different colors are used like color recording, or the case where gradation recording is used. For example, when a plurality of recording heads having the same color but different densities are used, the present invention can be applied regardless of the number of recording heads, and the same effect can be achieved.

Incidentally, the present invention, if the inkjet recording system,
For example, the present invention can be applied to a device using an electromechanical transducer such as a piezo element, and among others, it provides excellent effects in a bubble jet type ink jet recording apparatus and recording head proposed by Canon Inc.

According to such a method, it is possible to achieve higher density and higher definition of recording.

The representative configuration and principle are preferably performed using the basic principle disclosed in, for example, US Pat. Nos. 4,723,129 and 4,740,796.

This method can be applied to any of the so-called on-demand type and continuous type. In particular, in the case of the on-demand type, it corresponds to a sheet or a liquid path holding a liquid (ink). By applying at least one drive signal corresponding to the recording information and providing a rapid temperature rise exceeding nucleate boiling to the arranged electrothermal transducer, heat energy is generated in the electrothermal transducer, and recording is performed. This is effective because the film is boiled on the heat-acting surface of the head 1 and, as a result, bubbles in the liquid (ink) can be formed in one-to-one correspondence with the drive signal.

By discharging the liquid (ink) through the discharge opening by the growth and contraction of the bubble, at least one droplet is formed.

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 liquid (ink) having particularly excellent responsiveness can be achieved, which is more preferable. As the pulse-shaped drive signal, those described in US Pat. Nos. 4,463,359 and 4,434,262 are suitable.

Further, if the conditions described in US Pat. No. 4,313,124 relating to the invention relating to the temperature rise rate of the heat acting surface are adopted, more excellent recording can be performed.

As a configuration of the recording head, in addition to the combination configuration (a linear liquid flow path or a right-angled liquid flow path) of a discharge port, a liquid path, and an electrothermal converter as disclosed in each of the above-mentioned specifications, a heat acting section A configuration using U.S. Pat. No. 4,558,333 and U.S. Pat. No. 4,459,600, which disclose a configuration in which the is bent, is also included in the present invention.

In addition, JP-A-59-123670 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. Unexamined Japanese Patent Application Laid-Open (Kokai) Showa 59
The present invention is also effective as a configuration based on JP-A-138461.

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 present invention can be effectively applied to a full-line type recording head having a length corresponding to the maximum width of a recording medium on which a recording apparatus can record.

Such a recording head may have a configuration that satisfies the length by a combination of a plurality of recording heads, or a configuration as one integrally formed recording head.

In addition, even with the serial type printer as in the above example, the recording head fixed to the main unit or attached to the main unit enables electrical connection with the main unit and supply of ink from the main unit. The present invention is also effective when a replaceable chip type print head or a cartridge type print head having an ink tank provided integrally with the print head itself is used.

Further, the present invention is provided as a configuration of a recording apparatus. It is preferable to add recovery means for the recording head, preliminary auxiliary means, and the like, since the effects of the present invention can be further stabilized.

If these are specifically mentioned, for the recording head,
Capping means, cleaning means, pressurizing or suction means, preheating means using an electrothermal transducer or another heating element or a combination thereof, and performing a predischarge mode in which discharge is performed separately from recording. Is also effective for performing stable recording.

Regarding the type or number of print heads to be mounted, for example, in addition to one provided for a single color ink, a plurality of print heads are provided corresponding to a plurality of inks having different print colors and densities. May be used.

That is, for example, as the recording mode of the recording device,
Not only the recording mode of only the mainstream color such as black, but also a combination of a plurality of recording heads or a plurality of recording heads, any of which may be used, but at least one of multiple colors of different colors or full color by mixing colors. The present invention is also very effective for a device provided with such a device.

In addition, in the embodiments of the present invention described above, the ink is described as a liquid, but an ink that solidifies at room temperature or below, and softens or liquefies at room temperature, or in an ink jet system, Generally, the temperature of the ink itself is controlled 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. Anything should do.

In addition, 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 an 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 ink is liquefied, and the liquid ink is discharged. The present invention is also applicable to a case where ink having a property of being liquefied for the first time by heat energy is used.

In such a case, the ink is described in JP-A-54-56847 or JP-A-60-71260.
It may be configured such that it is opposed to the electrothermal converter in a state where it is held as a liquid or solid substance in the concave portion or through hole of the porous sheet.

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 inkjet recording apparatus according to the present invention includes, in addition to those used as image output terminals of information processing equipment such as a computer, a copying apparatus combined with a reader or the like, and a facsimile apparatus having a transmission / reception function. What you take may be used.

〔The invention's effect〕

As is apparent from the above description, according to the present invention, in an ink jet recording apparatus that performs recording by discharging ink from a recording unit to a recording material, a fixing unit for fixing the ink of the recorded recording material, A driving condition switching unit for changing a driving condition of the fixing unit, and a rear end portion detecting unit for detecting a rear end portion of the recording material,
Since the timing at which the rear end portion of the recording material passes through the fixing unit is detected, and the driving condition of the fixing unit at that time is switched by the driving condition switching unit so as to increase the fixing effect, energy consumption is reduced. And an ink jet recording apparatus capable of reliably performing ink fixing over the entire area including the rear end of the recording material.

[Brief description of the drawings]

FIG. 1 is a schematic longitudinal sectional view showing one embodiment of an ink jet recording apparatus according to the present invention, FIG. 2 is a partially cutaway perspective view showing the structure of an ink discharge section of the recording head in FIG. 1, and FIG. 1 is a block diagram showing a schematic functional configuration of a control system of a fixing unit of the recording apparatus of FIG. 1, FIG. 4 is a flowchart showing a control operation sequence of the fixing unit of the recording apparatus of FIG. 1, and FIG. FIG. 6 is a schematic longitudinal sectional view showing another embodiment of the ink jet recording apparatus, FIG. 6 is a block diagram showing a schematic functional configuration of a control system of a fixing unit of the recording apparatus of FIG. 5, and FIG. 6 is a flowchart illustrating a control operation sequence of a fixing unit of the apparatus. In the following, reference numerals indicating major components in the drawings are listed. DESCRIPTION OF SYMBOLS 1 ... Recording head, 2 ... Convey roller part, 3 ... First paper discharge roller part, 4 ... Second paper discharge roller part, 5 ... Fixing device (dry fixing device), 7 ... Recording material, 8: Rear end portion detection means, 9: Fixing device drive condition switching means, 10: Fixing device (backside heating plate), 13: Rear end portion detection means (counter control device), 14 ... Fuser driving condition switching means,
18: delivery roller, 100: CPU, 104: fixing device driving condition table, 105: fixing device driver, 110: counter, 111: CPU.

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hiroshi Taka 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Kenji Aono 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon (72) Inventor Jin Sugimoto 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Hiromitsu Hirabayashi 3-30-2, Shimomaruko 3-chome, Ota-ku, Tokyo Canon Inc. ( 58) Surveyed field (Int.Cl. ⁶ , DB name) B41J 2/01

Claims (3)

(57) [Claims] An ink jet recording apparatus that performs recording by discharging ink from a recording unit to a recording material; and a fixing unit configured to fix the recorded recording material ink.
A driving condition switching unit for changing a driving condition of the fixing unit; and a rear end portion detecting unit for detecting a rear end portion of the recording material, wherein the rear end portion of the recording material passes through the fixing unit. An ink jet recording apparatus comprising: detecting a timing; and switching a driving condition of the fixing unit at the timing by the driving condition switching unit so as to increase a fixing effect. 2. The recording device according to claim 1, wherein said recording means is a recording head for ejecting ink using thermal energy, and is an ink jet recording head including an electrothermal converter for generating thermal energy. The ink-jet recording apparatus according to claim 1. 3. The method according to claim 1, wherein the recording means discharges ink from a discharge port using a state change caused by growth of bubbles due to film boiling caused by thermal energy applied by the electrothermal transducer. The inkjet recording apparatus according to claim 2.