JPH10119307A - Recording device and defective jet sensing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve a problem of light quantity sensing sensitivity following the relative relation of the light receiving distance and light diffraction and carry out the secure no-jetting sensing, particularly in the case a recording head is long. SOLUTION: Light receiving elements 6 and 6' for sensing two beams 7 and 7' are set on the positions opposite each other in the sub-scanning direction F outside a recording area which a print-head 1100 having many nozzles arranged in the sub-scanning direction can scan, and nozzles on the position close to respective light receiving elements 6 and 6' are used, and defective jetting is specified based on the jet timing of ink drops and the sensing timing of the light receiving elements 6 and 6' while the ink drops are jetted and controlled successively in a time sequential manner from the nozzles toward the beams 7 and 7' outside of a recording area scannable by a printing heat 1100 with a number of nozzles in the scanning direction F.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet printing apparatus, and more particularly to a recording apparatus suitable for an ink jet printing apparatus having a large number of printing nozzles and performing high-speed continuous printing, and a method for detecting a discharge failure.

[0002]

2. Description of the Related Art Conventionally, in a printing method using an ink-jet method, an image is obtained by performing printing by discharging minute ink droplets from a fine nozzle provided in a recording head onto a recording medium. In this method, unlike electrophotography, there are few intervening steps until an image is formed.
The main feature is that the intended product can be obtained stably.

However, there is a problem that white stripes and the like are generated along the scanning direction during serial scanning by a recording head due to deviation or non-ejection of ink droplets.

[0004]

In particular, the causes of non-ejection of ink droplets include nozzle clogging due to dust or thickened ink, disconnection of a heater in a bubble jet system, and ink droplets covering a nozzle opening in a whim. It is thought that.

On the other hand, there is a method of detecting non-ejection of ink droplets using a light emitting element (LED) and a light receiving element (photodiode). In this method, a recording head is stopped at a predetermined detection position, ink droplets are ejected from a nozzle into a light beam emitted from a light emitting element, and a non-ejection nozzle, that is, an ejection failure nozzle is detected based on a change in output of a light receiving element receiving the light beam. Is to be detected.

However, if the distance between the light receiving element and the light emitting element is increased, it becomes difficult to detect the ink droplet on the light emitting element side, that is, the ink droplet at a position distant from the light receiving element due to light diffraction and the like. For this reason, in the printing method, there is a problem that the longer the print head becomes, the more it becomes impossible to reliably detect non-discharge.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the problem of light quantity detection sensitivity associated with the correlation between the light receiving distance and the light diffraction. An object of the present invention is to provide an apparatus and a method for detecting a discharge failure.

[0008]

According to the present invention, there is provided a recording apparatus which performs recording on the entire surface of a recording medium by feeding the recording medium in a sub-scanning direction with respect to the recording head in a main scanning direction. A plurality of nozzles provided in the recording head and arranged in the sub-scanning direction to eject ink droplets, and provided in a scanning region of the recording head outside the recording region, and emits a light beam along the arrangement direction of the nozzles. A beam emitting unit that emits light; a beam receiving unit that detects whether an ink droplet ejected from the nozzle has passed through a light beam emitted from the beam emitting unit; An ink droplet ejection control means for sequentially and time-sequentially controlling the ejection of ink droplets from each of the nozzles toward the light beam using the nozzles of the unit; An ejection failure nozzle identification unit that identifies an ejection failure nozzle based on each ejection timing for ejecting ink droplets and the detection timing of the beam receiving unit that detects the form of the ejected ink droplet. .

Here, a part of the nozzles at a position close to the beam receiving means has a light quantity detection sensitivity associated with a correlation between the light receiving distance from the position of the beam receiving means to the ink droplet ejection position and the light diffraction. A nozzle that exists within a range that maintains a certain level.

The present invention also relates to a recording apparatus for recording on the entire surface of a recording medium by feeding the recording medium in a sub-scanning direction with respect to the recording head in a main scanning direction. A plurality of nozzles provided on the head and arranged in the sub-scanning direction to eject ink droplets; and a plurality of nozzles provided in a scanning area of the recording head outside the recording area and emitting a first light beam along the arrangement direction of the nozzles. A first beam emitting unit; a first beam receiving unit configured to detect whether an ink droplet ejected from the nozzle passes through the first light beam emitted from the first beam emitting unit; A first ink droplet ejection control means for using a half of the nozzles from one end on the side close to the beam receiving means to the central portion, and sequentially and time-sequentially controlling ink droplets from each of the half nozzles toward the first light beam. When, And the ejection timing for ejecting ink droplets in the first light beam by the serial first ink droplet ejection control means, the first to detect the form of the ejected ink droplets
A first ejection failure nozzle identification unit that identifies an ejection failure nozzle based on the detection timing of the beam reception unit; and a first ejection failure nozzle identification unit that is arranged in parallel with the side on which the first beam reception unit is provided, and The second that emits two light beams
A beam emitting unit, which is disposed in parallel with the side on which the first beam emitting unit is provided, and in which a second light beam emitted from the second beam emitting unit passes ink droplets ejected from the nozzle. Using the second beam receiving means for detecting whether or not, and using the remaining half of the nozzles from one end on the side close to the second beam receiving means to the center, from each of the remaining half nozzles toward the second light beam Second ink droplet ejection control means for sequentially and sequentially controlling the ejection of ink droplets, each ejection timing for ejecting ink droplets in a second light beam by the second ink droplet ejection control means, And a second defective ejection nozzle specifying means for specifying a defective discharge nozzle based on the detection timing of the second beam light receiving means for detecting the form of the droplet.

The half nozzle from one end on the side closer to the first or second beam receiving means to the center thereof means the light receiving distance from the position of the beam receiving means to the ink droplet ejection position and the light diffraction. Nozzles within a range in which the light amount detection sensitivity associated with the correlation with a constant level is maintained at a constant level.

The present invention also relates to a recording apparatus for recording on the entire surface of a recording medium by feeding the recording medium in a sub-scanning direction with respect to the recording head in a main scanning direction. A plurality of nozzles provided on the head and arranged in the sub-scanning direction to eject ink droplets; and a plurality of nozzles provided in a scanning area of the recording head outside the recording area and emitting a first light beam along the arrangement direction of the nozzles. A first beam emitting unit, a first beam receiving unit that detects whether or not an ink droplet ejected from the nozzle has passed through the first light beam emitted from the first beam emitting unit; First ink droplet ejection control means for sequentially and time-sequentially controlling the ejection of ink droplets from all the nozzles toward the first light beam using nozzles; During ~ And the ejection timing for ejecting ink droplets, a first discharge-defective nozzle determination means for determining a discharge-defective nozzle and a detection timing of the first beam receiving means for detecting a form of the ejected ink drops, said first
A second beam emitting unit that is arranged in parallel with the side on which the beam receiving unit is provided and emits a second light beam along the arrangement direction of the nozzles; and a second beam emitting unit that is parallel to the side on which the first beam emitting unit is provided. A second beam receiving means for detecting whether or not an ink droplet ejected from the nozzle has passed through a second light beam emitted from the second beam emitting means; and A second ink droplet ejection control means for controlling the ejection of ink droplets sequentially from all the nozzles toward the second light beam in a time-series manner; A second defective ejection nozzle judging unit for judging a defective ejection nozzle based on each ejection timing for ejecting ink droplets and a detection timing of the second beam light receiving unit for detecting the form of the ejected ink droplet; Defective nozzle specifying means for specifying a defective nozzle based on the result of the determination by the first defective nozzle determination means and the result of the determination by the second defective nozzle determination means. Features.

The present invention also relates to a method for detecting ink droplets ejected from a nozzle using a recording head having nozzles arranged in the sub-scanning direction, the method comprising: In the above, when a light beam is emitted from the beam emitting means along the arrangement direction of the nozzles, and it is detected by the beam receiving means whether or not an ink droplet ejected from the nozzle has passed through the emitted light beam. Using a part of nozzles located at a position close to the beam receiving means, sequentially ejecting ink droplets from the part of each nozzle toward the light beam in time series, and discharging ink droplets into the light beam. The position of the defective ejection nozzle is specified from the ejection timing and the detection timing of the beam receiving unit for detecting the form of the ejected ink droplet.

The present invention also relates to a method for detecting ink droplets ejected from a nozzle using a recording head having nozzles arranged in the sub-scanning direction. A recording head is moved, a first light beam is emitted from a first beam emitting unit along a direction in which the nozzles are arranged, and a first light beam emitted from the first beam emitting unit is emitted.
When detecting whether or not the ink droplet ejected from the nozzle has passed through the light beam by the first beam receiving unit,
Using a half nozzle from one end on the side close to the first beam receiving means to the central portion, ink droplets are sequentially ejected from the respective half nozzles toward the first light beam in a time series manner. Each ejection timing for ejecting ink droplets therein, and the first method for detecting the form of the ejected ink droplets.
An ejection failure nozzle is identified from the detection timing of the beam receiving unit, and the recording head is moved from the first inspection region to a second inspection region outside the recording region, and the second beam emitting unit is arranged along the nozzle arrangement direction. When the second beam receiving means detects whether or not the ink droplet ejected from the nozzle has passed through the second light beam emitted from the second beam emitting means from the second light beam, The second
Using half the nozzles from one end on the side close to the beam receiving means to the central part, ink droplets are sequentially ejected from the respective half nozzles toward the second light beam in a time-series manner, and the ink is discharged into the second light beam. An ejection failure nozzle is specified based on each ejection timing of ejecting a droplet and the detection timing of the second beam light receiving means for detecting the form of the ejected ink droplet.

Further, the present invention is a method for detecting an ink droplet ejected from a nozzle by using a recording head having nozzles arranged in the sub-scanning direction, wherein the method comprises the steps of: A recording head is moved, a first light beam is emitted from a first beam emitting unit along a direction in which the nozzles are arranged, and a first light beam emitted from the first beam emitting unit is emitted.
When detecting whether or not the ink droplet ejected from the nozzle has passed through the light beam by the first beam receiving unit,
Using all the nozzles, ink droplets are sequentially and sequentially ejected from all the nozzles toward the first light beam, and each ejection timing for ejecting the ink droplets in the first light beam, and The first method for detecting the form of an ink droplet
An ejection failure is determined from the detection timing of the beam receiving unit, and the recording head is moved from the first inspection region to a second inspection region outside the recording region, and the recording head is moved from the second beam emitting unit along the nozzle arrangement direction. When the second beam receiving unit detects whether or not the ink droplet ejected from the nozzle passes through the second light beam emitted from the second beam emitting unit, the second light beam is emitted. The nozzles are used to sequentially eject ink droplets from all the nozzles toward the second light beam in a time-series manner, and the respective ejection timings for ejecting ink droplets in the second light beam; An ejection failure is determined from the detection timing of the second beam light receiving means for detecting the form of the droplet, and the determination result based on the detection of the first beam light receiving means and the second When the the determination result based on the detection of the over arm receiving means it is determined to be both ejection failure nozzle,
Alternatively, when the determination result when the nozzle is located at a position close to the first or second light receiving unit is determined to be a defective discharge nozzle, the nozzle is specified as a defective discharge nozzle.

Here, the nozzle located at a position close to the first or second beam light receiving means means a light amount associated with a correlation between a light receiving distance from the position of the beam light receiving means to the ink droplet ejection position and light diffraction. A nozzle that exists in a range where the detection sensitivity maintains a certain level.

Further, the recording head may be constituted by an ink jet head which performs recording by discharging ink. In this case, an ink jet head can be configured by generating bubbles in the ink by using thermal energy and discharging the ink with the generation of the bubbles.

Further, a fabric may be used as the recording medium, and the fabric may be printed by discharging ink droplets onto the fabric.

[0019]

Embodiments of the present invention will be described below in detail with reference to the drawings.

First, an embodiment of the present invention will be described with reference to FIGS.
It will be described based on. In this example, a textile printing apparatus will be described as an example of the inkjet printing apparatus. First, the overall configuration of the present apparatus will be described with reference to FIGS.

In FIG. 7, reference numeral 1 denotes a cloth as a recording medium. The cloth 1 was unwound according to the rotation of the unwind roller 11, and was transported in a substantially horizontal direction by the transport unit 100 provided at a portion facing the printer unit 1000 via the intermediate rollers 13 and 15. After, the feed roller 17
Then, it is wound on a winding roller 21 via an intermediate roller 19.

The transport section 100 generally includes transport rollers 110 and 120 provided on the upstream and downstream sides of the printer section 1000 in the transport direction of the cloth 1, and an endless belt-shaped transport belt wound between the rollers. 130, and a pair of platen rollers 140 provided to extend the transport belt 130 with an appropriate tension within a predetermined range so as to regulate the printing surface of the fabric 1 flat when printing by the printer unit 1000 and to improve flatness. ing. Here, in the present embodiment, the transport belt 130 is made of a metal as disclosed in Japanese Patent Application Laid-Open No. H5-212851.
As shown in a magnified view, the surface is adhered to the conveyor belt 130 via an adhesive layer 133 to ensure flatness during printing.

The printing material 1000 is applied by the printer unit 1000 in the area between the platen rollers 140 to the cloth 1 conveyed in the state where the flatness is ensured, and the conveyance belt 130 or the adhesive The film is peeled off from the layer 133 and is wound up by the winding roller 21, and a drying process is performed by the drying heater 600 on the way. In addition, as the drying heater 600, an appropriate heater such as a heater that blows warm air onto the cloth 1 or a heater that irradiates infrared rays can be used.

FIG. 8 shows the printer section 1000 and the cloth 1.
Is schematically shown. FIG. 9 shows the carriage 1010
1 shows a scanning system.

In FIG. 8, the printer unit 1000 operates in a direction different from the transport direction (sub-scanning direction) F of the cloth 1, for example, the width direction (main scanning direction) of the cloth 1 orthogonal to the transport direction F.
It has a carriage 1010 that is scanned by S. 10
Reference numeral 20 denotes a support rail extending in the main scanning direction S. The support rail 120 supports and guides the slider 1012 fixed to the carriage 1010.
22 is supported. Reference numeral 1030 denotes a motor serving as a driving source for performing main scanning of the carriage 1010. The driving force of the motor 1030 is transmitted to the carriage 1010 via a belt 1032 to which the carriage 1010 is fixed and other appropriate transmission mechanisms.

The carriage 1010 moves the print head 1100 having a large number of printing agent applying elements arranged in a predetermined direction (in this example, the transport direction F) in a direction different from the transport direction F (in this example, the main scanning direction S). , And in the present example, it is held in two stages in the transport direction F. In the print head 1100 of each stage, the color used for the printing agent having a different color and the number of heads can be conveniently selected according to the image to be formed on the fabric 1 or the like, but are, for example, three primary colors of printing. Yellow (Y), magenta (M),
And cyan (C) or black (Bk). Instead of, or in addition to, these, special colors (metallic colors such as gold and silver, vivid red and blue, etc.) that cannot or cannot be expressed with the three primary colors can be used. In addition, even when the color is the same, a plurality of printing agents may be used according to the density.

In this embodiment, a plurality of print heads 1100 arranged in the main scanning direction S are provided in two stages in the transport direction F as shown in FIG. Print head 11 of each stage
The color of the printing agent used, the number of the printing agents, the number of the printing agents, the order of the printing agents, and the like may be the same or different for each stage depending on the image to be printed. Further, printing can be performed again by the next-stage print head 1100 for an area to be printed by the main scanning of the one-stage print head 1100 (complementary thinning printing by the respective-stage print heads 1100). Alternatively, a high-speed printing may be performed by sharing the printing area. Further, the number of stages of the print head 1100 is not limited to two, but may be one or three or more.

In this example, the print head 1100
For example, an ink-jet head, for example, a bubble jet head having a heating element that generates thermal energy that causes film boiling of ink as energy used for discharging ink is used. Then, with respect to the fabric 1 which is conveyed in a substantially horizontal direction by the conveyance unit 100, the ink ejection ports as the printing agent applying element are used in a state where the ink ejection ports face downward, so that the head difference between each ejection port is eliminated. The conditions are made uniform so that a good image can be formed, and a uniform recovery process can be performed on all the ejection openings.

In FIG. 9, the capping means 1220
Is provided in the support section 1200 at the top of the housing 103,
At the time of non-printing operation, the print head 1100 comes into contact with the ejection opening surface of the print head 1100 to suppress its drying and the intrusion of foreign matter, or to remove the foreign matter. Specifically, during a non-printing operation, the print head 1100 is
Move to a position facing 20. Thus, the capping unit 1220 is driven in the cap direction by the driving unit 1210, and performs capping by pressing an elastic member or the like against the nozzle discharge port surface.

The clogging prevention means 1231 receives the discharged ink when the print head 1100 performs a discharge operation (preliminary discharge operation) for equalizing discharge conditions by ink refresh. The clogging prevention means 1231 is provided at a portion facing the print head 1100 outside the recording area of the print head 1100, and a liquid receiving member 1231a for absorbing and receiving pre-discharged ink is provided between the capping means 1220 and the print area P. And on the opposite side. In addition,
A liquid holding member (not shown) is provided in the liquid receiving member 1231a, and a sponge-like porous member or the like is used as a material thereof.

Further, between the capping means 1220 and the print area P, a wiping means (wiping blade) capable of rubbing the nozzle outlet surface of the print head 1100
70 is disposed, and wipes off the machine, dust and the like by wiping adhered to the nozzle discharge port surface by the rubbing.
50 is a receiving tray for receiving dust and the like.

Next, a method for detecting a defective ejection nozzle, that is, a head, according to the present invention will be described with reference to FIGS. In FIG. 1, the print head 1100 has a large number of nozzles N on its lower surface, and discharges ink droplets toward the clogging prevention means 1231. Arrow 3
Indicates the main scanning direction S, and the carriage 1010 is moved in the main scanning direction S by the belt 1032. 8 ',
Reference numeral 8 "denotes a recording medium, which is fed in the sub-scanning direction F indicated by the arrow 4. 8 'indicates an already printed area, and 8" indicates an area to be printed.

In FIG. 1, light emitting elements 5, 5 'and light receiving elements 6, 6' are provided outside the recording area in pairs. That is, the light emitting element 5 and the light receiving element 6 are arranged along the sub-scanning direction F in pairs. In this case, the direction of the beam 7 emitted from the light emitting element 5 matches the arrangement direction of the nozzles N of the print head 1100 (the sub-scanning direction F). Thereby, each nozzle N
Ink droplets ejected from the beam 7 can be injected into the beam 7.

Similarly, the light emitting element 5 'and the light receiving element 6' are arranged in pairs in the sub-scanning direction F. However, the light emitting element 5 'is provided on the light receiving element 6 side, and the light receiving element 6' is provided on the light emitting element 5 side, whereby the beam 7 'emitted from the light emitting element 5' is similar to the beam 7. Then, ink droplets are ejected from each nozzle N of the print head 1100.

Here, an example of an experiment was conducted to examine how the detection of non-ejection changes when the position where an ink droplet is ejected from the nozzle N to the beam 7, 7 'becomes farther from the light receiving elements 6, 6'. Will be described based on FIG. 4 and FIG.

In FIG. 4, an arrow indicated by 7 is a narrowed beam (laser beam). 5 is a light emitting element,
6 is a light receiving element. While changing the position of the beam 7 from the position 34 close to the light emitting element 5 to the position 35 close to the light receiving element 6, ink droplets are ejected from the print head 1100 into the clogging prevention means 1231.

FIG. 5 shows the results when the ink droplets were ejected.
Shown in FIG. 5 shows the light intensity ratio on the vertical axis and the light receiving element 6 on the horizontal axis.
Distance from the ink drop. From FIG. 5, it is understood that the detection of the ejection failure becomes more difficult as the distance from the light receiving element 6 increases. Therefore, by arranging two detection systems and detecting portions close to the light receiving sensor side, it is possible to detect a discharge failure with respect to a larger head.

Therefore, as shown in FIG. 1, two light-emitting elements 5, 5 'and light-receiving elements 6, 6' are arranged on opposite sides, respectively, and two beams 7,
Run 7 '. FIG. 2 is a sectional view at the position of the beam 7, and FIG. 3 is a sectional view at the position of the beam 7 '. As shown in FIGS. 2 and 3, the print head 1100 is fixed at the positions of the beams 7, 7 ', and in response to the arrow 7, a certain amount of ink droplet is applied as shown by arrows A, B, C,. Driving in a cycle, arrows A ', B',
As shown by C ',..., Ink droplets are ejected at a certain period.

As shown in FIG. 6, the determination as to whether or not a discharge failure nozzle exists is made by the light quantity (in this case, indicated by voltage) sensed by the light receiving elements 6, 6 'on the vertical axis, and the time on the horizontal axis. If there is a position where the voltage does not change (a position where the change in voltage indicated by a dotted line in FIG. 6 does not appear), it is determined that no ink droplet is ejected there.
As described above, by determining whether or not the light amount detection sensitivity (voltage) involving the correlation between the light receiving distance and the light diffraction keeps a constant level, the half of the nozzles N closer to the light receiving elements 6, 6 ', respectively, is determined. , It is possible to detect a defective ejection nozzle.

From the nozzle N of such a print head 1100, arrows A, B, C,... Or arrows A ', B',
As shown by C ',..., The ink droplets are ejected by a control (ink droplet ejection control means) in which ink droplets are sequentially ejected in a certain cycle in a time series, or by a voltage change appearing by detecting a light amount change of the light receiving elements 6, 6'. The control for determining whether or not the ejection has been performed and identifying the ejection failure nozzle (ejection failure nozzle identification means)
The control is executed by a control unit (CPU or the like) in the apparatus main body that controls the print head 1100 comprehensively.

As described above, the print head 1100
Is divided into two and the ejection control of the nozzle N is performed.
By detecting the ejection failure of the nozzles N which are closer to 6 ′, the ejection failures of all the nozzles N can be reliably detected even when the print head 1100 is long.

Next, a second embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIG. In general, when the print head 1100 is long, an ink droplet is ejected from a nozzle N far from the light receiving elements 6, 6 ',
There is a problem of light diffraction between the case where an ink droplet is ejected from and the amount of light sensed by the light receiving elements 6, 6 'differs.

In the present embodiment, including the first embodiment described above, a new ejection failure detection method is proposed in consideration of such light quantity detection sensitivity. The apparatus configuration of this example is the same as that of the above-described first embodiment, and a method of ink droplet ejection control and ejection defective nozzle determination control will be described below.

First, as shown in FIGS. 10 and 11, the print head 1100 is moved above the beam 7 and ink droplets are sequentially ejected from all the nozzles N to the beam 7 by arrows A, B, C,. . Next, as shown in FIG. 12, the print head 1100 is moved above the beam 7 ', and arrows A', B ', C',... . That is, one nozzle N
In this case, the detection of the ejection failure is performed twice.

If a certain nozzle N is the light receiving element 6,
If it is determined that the ejection failure occurs near 6 ', but it is determined that ejection occurs near the light emitting elements 5' and 5, the nozzle N is detected again as a detection error for the nozzle N. . Conversely, when it is determined that the ink is ejected when it is close to the light receiving elements 6 and 6 ′, but it is determined that the ejection is defective when it is near the light emitting elements 5 ′ and 5, it is determined that the ink is ejected. In addition, when a discharge failure is detected both times, it is determined that a discharge failure has occurred, whereby a discharge failure nozzle can be specified. In this manner, by performing the ink ejection control and the control of the determination of the ejection failure nozzle, the ejection failure is detected twice for one nozzle, so that the accuracy of the ejection failure determination can be improved.

Next, the entire process of ink-jet printing and recording will be described. Using the above-described inkjet recording device,
After the inkjet printing process, the fabric is dried (including natural drying). Subsequently, a step of diffusing the dye on the fabric fiber and reacting and fixing the dye to the fiber is performed. By this step, it is possible to obtain sufficient color-forming properties and fastness due to fixation of the dye.

This diffusion and reaction fixing step may be a conventionally known method, for example, a steaming method. In addition,
In this case, the fabric may be subjected to an alkali treatment before the printing step.

Thereafter, in a post-treatment step, unreacted dye is removed and substances used in the pre-treatment are removed.
Finally, the record is completed through an orderly finishing process such as defect correction and ironing.

In particular, as a fabric for ink-jet printing, (1) the ink can be colored to a sufficient concentration;
(2) high ink dyeing rate; (3) quick drying of the ink on the fabric; (4) less occurrence of irregular ink bleeding on the fabric; And high performance such as excellent transportability. In order to satisfy these required performances, in the present invention, the fabric can be subjected to a pretreatment beforehand, if necessary. For example, Japanese Patent Application Laid-Open No. 62-53492 discloses cloths having an ink receiving layer, and Japanese Patent Publication No. 3-46589 proposes a cloth containing a reduction inhibitor or an alkaline substance. I have. As an example of such a pretreatment, there can be mentioned a treatment in which a cloth contains a substance selected from an alkaline substance, a water-soluble polymer, a synthetic polymer, a water-soluble metal salt, urea and thiourea.

Examples of the alkaline substance include alkali metal hydroxides such as sodium hydroxide and potassium hydroxide;
Examples thereof include amines such as mono-, di-, and triethanolamine, and alkali metal carbonates or bicarbonates such as sodium carbonate, potassium carbonate, and sodium bicarbonate. Furthermore, there are organic acid metal salts such as calcium acetate and barium acetate, ammonia and ammonia compounds. Further, sodium trichloroacetate which becomes an alkaline substance under steaming and dry heat may be used. Particularly preferred alkaline substances include sodium carbonate and sodium bicarbonate used for dyeing reactive dyes.

Examples of the water-soluble polymer include starch substances such as corn and wheat; cellulosic substances such as carboxymethylcellulose, methylcellulose and hydroxyethylcellulose; sodium alginate;
Locust bean gum, tragacanth gum, guar gum,
Examples include polysaccharides such as tamarind seeds, protein substances such as gelatin and casein, and natural water-soluble polymers such as tannin substances and lignin substances.

Examples of the synthetic polymer include a polyvinyl alcohol compound, a polyethylene oxide compound, an acrylic acid-based water-soluble polymer, and a maleic anhydride-based water-soluble polymer. Among them, polysaccharide polymers and cellulose polymers are preferable.

Examples of the water-soluble metal salt include compounds which form typical ionic crystals and have a pH of 4 to 10, such as halides of alkali metals and alkaline earth metals. Representative examples of such compounds include, for example, NaCl, Na ₂ S
O ₄ , KCl and CH ₃ COONa, and the like, and examples of the alkaline earth metal include CaCl ₂ and Mg
Cl _{2 and the} like. Among them, salts of Na, K and Ca are preferred.

The method for incorporating the above substances into the fabric in the pretreatment is not particularly limited, and examples thereof include a commonly used dipping method, padding method, coating method and spraying method.

Further, since the printing ink applied to the fabric for ink-jet printing merely adheres when applied to the fabric, it is necessary to carry out a fixing step of the dye or the like in the ink onto the fiber. Is preferred. Such a fixing step may be performed by a conventionally known method, for example, a steaming method, an HT steaming method, a thermofix method,
When a fabric which has been previously alkali-treated is not used, an alkali pad steam method, an alkali blotch steam method, an alkali shock method, an alkali cold fix method and the like can be mentioned. The fixing step may or may not include a reaction process depending on the dye. As an example of the latter, there is a method in which fibers are impregnated and do not physically separate. As the ink, any suitable ink can be used as long as it has a required pigment, and the ink is not limited to a dye and may include a pigment.

Further, the removal of unreacted dye and the substance used in the pretreatment can be carried out after the above-mentioned reaction fixing step by washing according to a conventionally known method. In addition, it is preferable to use a conventional fixing process in combination with this cleaning.

The printed material which has been subjected to the post-processing steps described above is thereafter cut into a desired size, and the cut pieces are subjected to a process for obtaining a final processed product such as sewing, bonding and welding. Is applied to obtain clothes such as one-piece dresses, dresses, ties, and swimwear, duvet covers, sofa covers, handkerchiefs, curtains, and the like. A method of processing a fabric by sewing or the like to produce clothing or other daily necessities is a conventionally known technique.

Examples of the printing medium include fabrics, wall cloths, threads used for embroidery, wallpaper, paper, OHP films, alumites and other plate-like materials, and various types of liquids to which a predetermined liquid can be applied using ink jet technology. The cloth includes all woven fabrics, non-woven fabrics and other fabrics regardless of the material, weave or knitting.

The present invention can employ not only the above-described ink-jet printing method but also various printing methods. In the case where the ink-jet printing method is used, among them, thermal energy is used as energy used for ink ejection. An excellent effect is provided by using a method of generating a change in the state of the ink by the thermal energy, that is, a bubble jet type print head and printing apparatus proposed by Canon Inc. This is because such a method can achieve higher density and higher definition of the print.

The typical configuration and principle are described in, for example, US Pat. Nos. 4,723,129 and 4,740.
It is preferable to use the basic principle disclosed in the specification of Japanese Patent No. 796. This method is a so-called on-demand type,
Although it can be applied to any type of continuous type, in particular, in the case of the on-demand type, it can be applied to a sheet holding liquid (ink) or an electrothermal converter arranged corresponding to the liquid path. Applying at least one drive signal corresponding to the printing information and providing a rapid temperature rise exceeding nucleate boiling, causing the electrothermal transducer to generate thermal energy, causing film boiling on the heat-acting surface of the printhead. This is effective because bubbles can be formed in the liquid (ink) corresponding to this drive signal on a one-to-one basis. 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, those described in US Pat. Nos. 4,463,359 and 4,345,262 are suitable. If the conditions described in U.S. Pat. No. 4,313,124 relating to the rate of temperature rise of the heat acting surface are adopted, more excellent printing can be performed.

The structure of the print head is not limited to the combination of a discharge port, a liquid path, and an electrothermal converter (a linear liquid flow path or a right-angled liquid flow path) as disclosed in the above-mentioned specifications. A configuration using U.S. Pat. No. 4,558,333 or U.S. Pat. No. 4,459,600, which discloses a configuration in which a heat acting portion is arranged in a bending region, is also included in the present invention. In addition, for multiple electrothermal transducers,
JP-A-59-123670 which discloses a configuration in which a common slit is used as a discharge portion of an electrothermal transducer and JP-A-59-123670 which discloses a configuration in which an opening for absorbing a pressure wave of heat energy corresponds to a discharge portion. The effect of the present invention is effective even in a configuration based on JP-A-138461. That is, according to the present invention, printing can be performed reliably and efficiently regardless of the form of the print head.

In addition, it goes without saying that the print head can be configured in accordance with the form of the printing apparatus, and in the case of the so-called line printer form, the ejection openings are arranged over a range corresponding to the width of the print medium. What should be done. In addition, as a serial type print head as in the above example, a print head fixed to the apparatus main body, or an ink supply from the apparatus main body or an ink supply from the apparatus main body by being attached to the apparatus main body. The present invention is also effective when a replaceable chip-type printhead that can be used or a cartridge-type printhead in which an ink tank is provided integrally with the printhead itself is used.

In addition, it is preferable to add a print head ejection recovery unit, a preliminary auxiliary unit, and the like as the configuration of the printing apparatus of the present invention since the effects of the present invention can be further stabilized. If you list these specifically,
Pre-heating means for heating using a capping means, a cleaning means, a pressure or suction means, an electrothermal converter or another heating element or a combination thereof for the print head, Pre-discharge means for performing another discharge can be given.

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 lower and which softens or liquefies at room temperature may be used. In general, the ink jet method generally controls the temperature of the ink itself 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. Sometimes, the ink may be in a liquid state. In addition, in order 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 to prevent evaporation of the ink, the ink is solidified in a standing state and heated. May be used. In any case, the ink liquefies by the application of the heat energy according to the print signal,
The present invention is also applicable to a case in which an ink having a property of being liquefied for the first time by the application of thermal energy, such as an ink in which a liquid ink is ejected and an ink which starts solidifying when it reaches a print medium, is used. . In such a case, the ink is held in a state in which the ink is held as a liquid or a solid in the concave portion or through hole of the porous sheet as described in JP-A-54-56847 or JP-A-60-71260. Alternatively, it may be configured to face the electrothermal converter. 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 an embodiment of the present invention, in addition to the one used as an image output terminal of an information processing device such as a computer, a form of a copying apparatus combined with a reader or the like may be adopted.

[0066]

As described above, according to the present invention, an ejection failure detection device including a light emitting element and a light receiving element is provided outside a recording area scanable by a print head having a large number of nozzles arranged in the sub-scanning direction. Are arranged, and the ink droplets are sequentially controlled in time series from the nozzles toward the beam by using nozzles located close to the light receiving element, and the discharge is performed based on the discharge timing of the ink drop and the detection timing by the light receiving element. Since the defective nozzle is determined, the problem of the light amount detection sensitivity associated with the correlation between the light receiving distance and the light diffraction can be cleared, and the defective discharge nozzle can be reliably specified. Accordingly, even when the print head is particularly long, the discharge control is performed by dividing the head into two and dividing the nozzle into halves, and detecting the discharge failure of the half nozzle using the two light receiving elements. The accuracy of detection can be improved.

In the case where the ejection failure detection is performed using the two light receiving elements as described above, it is possible to perform the non-discharge discrimination control by detecting the ink droplets ejected from all the nozzles by the respective light receiving elements. As a result, the accuracy of determining a defective ejection nozzle can be further improved.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a schematic configuration of an ejection failure detection device according to an embodiment of the present invention.

FIG. 2 is a side view showing the principle of performing non-ejection detection using half the nozzles.

FIG. 3 is a side view showing the principle of performing non-discharge detection using the remaining half of the nozzles in FIG. 2;

FIG. 4 is a side view showing an experimental example for examining a correlation between a light receiving distance and an ink droplet ejection position.

FIG. 5 is a graph showing a relationship between a light receiving distance and a light amount ratio.

FIG. 6 is a waveform diagram showing a voltage waveform detected by a light receiving element when ink droplets are sequentially ejected in a time series from a nozzle.

FIG. 7 is a cross-sectional view illustrating a schematic configuration of a textile printing apparatus that is an example of an inkjet printing apparatus including a non-discharge detection apparatus.

FIG. 8 is a perspective view showing a schematic configuration of a printing unit of the apparatus shown in FIG.

FIG. 9 is a cross-sectional view of the print unit shown in FIG.

FIG. 10 is a perspective view showing an experimental example for examining a correlation between a light receiving distance and an ink droplet ejection position.

FIG. 11 is a side view showing the principle of performing non-ejection detection sequentially from one direction using all nozzles.

FIG. 12 is a side view showing the principle of performing non-discharge detection sequentially from a direction opposite to that of FIG. 11 using all nozzles.

[Explanation of symbols]

 Reference Signs List 1 recording medium 3 main scanning direction (S) 4 sub-scanning direction (F) 5 beam emitting means (first beam emitting means) 5 'beam emitting means (second beam emitting means) 6 beam receiving means (first beam receiving means) 6 'beam receiving means (second beam receiving means) 1100 recording head N nozzle

Claims (17)

[Claims] 1. A recording apparatus for recording on the entire surface of a recording medium by feeding the recording medium in a sub-scanning direction with respect to the recording head in the main scanning direction, wherein the recording apparatus is provided on the recording head. A plurality of nozzles arranged in the sub-scanning direction to eject ink droplets; a beam emitting unit provided in a scanning area of the recording head outside a recording area, and emitting a light beam along the arrangement direction of the nozzles; A beam receiving unit that detects whether an ink droplet ejected from the nozzle has passed through the light beam emitted from the beam emitting unit, and using a part of nozzles at a position close to the beam receiving unit,
An ink droplet ejection control means for sequentially and sequentially controlling the ejection of ink droplets from each of the nozzles toward the light beam; and each ejection timing for ejecting ink droplets in the light beam by the ink droplet ejection control means. And a discharge failure nozzle specifying means for specifying a discharge failure nozzle based on the detection timing of the beam receiving means for detecting the form of the discharged ink droplet. 2. A partial nozzle close to the beam receiving means has a certain level of light amount detection sensitivity associated with a correlation between a light receiving distance from the position of the beam receiving means to an ink droplet ejection position and light diffraction. 2. The recording apparatus according to claim 1, wherein the nozzles are located in a range where the pressure is maintained. 3. A recording apparatus which performs recording on the entire surface of a recording medium by feeding the recording medium in a sub-scanning direction with respect to the recording head in the main scanning direction. A plurality of nozzles arranged in the sub-scanning direction to eject ink droplets, and a first beam emission provided in a scanning area of the recording head outside the recording area and emitting a first light beam along the arrangement direction of the nozzles Means, a first beam light receiving means for detecting whether or not an ink droplet ejected from the nozzle has passed through a first light beam emitted from the first beam emitting means, and a first beam light receiving means. A first ink droplet ejection control unit that uses half of the nozzles from one end on the near side to the center, and sequentially and sequentially controls the ejection of ink droplets from each half of the nozzles toward the first light beam; 1 in A discharge failure nozzle is identified from each discharge timing for discharging ink droplets in the first light beam by the droplet discharge control means and the detection timing of the first beam light receiving means for detecting the form of the discharged ink drops. 1 ejection failure nozzle identification means, a second beam emission means which is arranged in parallel with the side where the first beam light reception means is provided, and emits a second light beam along the arrangement direction of the nozzles, A second light beam emitted from the second beam emitting means, which is disposed in parallel with the side on which the one beam emitting means is provided, and detects whether or not the ink droplet ejected from the nozzle has passed through the second light beam. Two-beam light receiving means, and the remaining half of the nozzles from one end on the side close to the second beam light-receiving means to the central portion, and sequentially ink droplets from each of the remaining half nozzles toward the second light beam. A second ink droplet ejection control means for controlling ejection in time series, each ejection timing for ejecting an ink droplet in a second light beam by the second ink droplet ejection control means, and a form of the ejected ink droplet. 2. A printing apparatus, comprising: a second ejection failure nozzle specifying unit that identifies a failed ejection nozzle based on a detection timing of the second beam receiving unit that detects the ejection. 4. A half nozzle from one end on the side closer to the first or second beam light receiving means to a central portion, the light receiving distance from the position of the beam light receiving means to the ink droplet ejection position and the light diffraction. 4. The recording apparatus according to claim 3, wherein the nozzles are present in a range where a light amount detection sensitivity associated with the correlation maintains a constant level. 5. A recording apparatus which performs recording on the entire surface of a recording medium by feeding the recording medium in a sub-scanning direction with respect to the recording head in a main scanning direction. A plurality of nozzles arranged in the sub-scanning direction to eject ink droplets, and a first beam emission provided in a scanning area of the recording head outside the recording area and emitting a first light beam along the arrangement direction of the nozzles Means, a first beam receiving means for detecting whether or not an ink droplet ejected from the nozzle has passed through a first light beam emitted from the first beam emitting means, and using all the nozzles, First from all the nozzles
First ink droplet ejection control means for sequentially and sequentially controlling the ejection of ink droplets toward the light beam; each ejection timing for ejecting ink droplets in the first light beam by the first ink droplet ejection control means; A first ejection failure nozzle judging unit for judging an ejection failure nozzle from a detection timing of the first beam reception unit for detecting the form of the ejected ink droplet; and a parallel to a side where the first beam reception unit is provided. A second beam emitting unit that emits a second light beam along the arrangement direction of the nozzles; and a second beam emitting unit that is arranged parallel to a side on which the first beam emitting unit is provided. A second beam receiving means for detecting whether or not an ink droplet ejected from the nozzle has passed through a second light beam emitted from the means; and all the nozzles using all the nozzles From the second
Second ink droplet ejection control means for sequentially and sequentially controlling the ejection of ink droplets toward the light beam; each ejection timing for ejecting ink droplets in the second light beam by the second ink droplet ejection control means; A second ejection failure nozzle judging unit for judging an ejection failure nozzle based on a detection timing of the second beam light reception unit for detecting a form of the ejected ink droplet; and a first ejection failure nozzle for the same nozzle. A printing apparatus, comprising: a defective discharge nozzle specifying means for specifying a defective discharge nozzle based on a result of the determination by the determination means and a result of the determination by the second defective discharge nozzle determination means. 6. The recording apparatus according to claim 1, wherein the recording head is an inkjet head that performs recording by discharging ink. 7. The recording apparatus according to claim 6, wherein the ink jet head generates bubbles in the ink using thermal energy, and discharges the ink as the bubbles are generated. 8. The recording apparatus according to claim 1, wherein a cloth is used as the recording medium, and printing is performed by discharging ink droplets onto the cloth. 9. A method for detecting ink droplets ejected from a nozzle using a recording head having nozzles arranged in a sub-scanning direction, wherein the nozzle is located in a scanning area of the recording head outside a recording area. When a light beam is emitted from the beam emitting means along the arrangement direction of the beam, and it is detected by the beam receiving means whether or not the ink droplet ejected from the nozzle has passed through the emitted light beam, Using a part of the nozzles located at a position close to the means, sequentially discharging ink droplets from the part of the nozzles toward the light beam in a time-series manner, and discharging timings for discharging the ink droplets in the light beam;
A method of detecting a defective discharge, wherein the position of a defective discharge nozzle is specified based on the detection timing of the beam receiving means for detecting the form of the discharged ink droplet. 10. Some of the nozzles at a position near the beam receiving means have a certain level of light amount detection sensitivity according to the correlation between the light receiving distance from the position of the beam receiving means to the ink droplet ejection position and the light diffraction. 10. The method according to claim 9, wherein the nozzles are located within a range where the pressure is maintained. 11. A method for detecting an ink droplet ejected from a nozzle using a recording head having nozzles arranged in a sub-scanning direction, wherein the recording head is moved to a first inspection area outside the recording area. The first light beam is emitted from the first beam emitting means along the arrangement direction of the nozzles, and the ink droplets ejected from the nozzles pass through the first light beam emitted from the first beam emitting means. When it is detected by the first beam receiving means whether or not it has been performed, half the nozzles from one end on the side close to the first beam receiving means to the center are used, and from each of the half nozzles toward the first light beam. Ink droplets are sequentially ejected in chronological order, each ejection timing for ejecting the ink droplets in the first light beam, and the first method for detecting the form of the ejected ink droplets.
An ejection failure nozzle is specified based on the detection timing of the beam receiving unit, and the recording head is moved from the first inspection region to a second inspection region outside the recording region, and a second beam emitting unit is arranged along the nozzle arrangement direction. A second light beam is emitted from the second beam receiving means, and when the second beam light receiving means detects whether or not an ink droplet ejected from the nozzle has passed through the second light beam emitted from the second beam emitting means, A half nozzle from one end on the side close to the second beam receiving means to the center is used, and ink droplets are sequentially ejected from the respective half nozzles toward the second light beam in a time-series manner. Each ejection timing for ejecting ink droplets therein, and the second for detecting the form of the ejected ink droplets.
An ejection failure detection method, characterized by identifying an ejection failure nozzle from a detection timing of a beam receiving unit. 12. A half nozzle from one end on the side closer to the first or second beam light receiving means to a center portion, the light receiving distance from the position of the beam light receiving means to the ink droplet ejection position and the light diffraction. 12. The ejection failure detection method according to claim 11, wherein the nozzles are present in a range where the light quantity detection sensitivity associated with the correlation maintains a constant level. 13. A method for detecting an ink droplet ejected from a nozzle using a recording head having nozzles arranged in a sub-scanning direction, wherein the recording head is moved to a first inspection area outside the recording area. The first light beam is emitted from the first beam emitting means along the arrangement direction of the nozzles, and the ink droplets ejected from the nozzles pass through the first light beam emitted from the first beam emitting means. When the first beam receiving means detects whether or not the ink droplets have been ejected, ink droplets are sequentially ejected from all the nozzles toward the first light beam using all the nozzles, and the first light beam Each of the ejection timings at which the ink droplets are ejected, and the first method for detecting the form of the ejected ink droplets.
A discharge failure is determined from the detection timing of the beam receiving unit, and the recording head is moved from the first inspection region to a second inspection region outside the recording region, and the recording head is moved from the second beam emitting unit along the nozzle arrangement direction. Emitting a second light beam, and detecting, by the second beam light receiving means, whether or not an ink droplet ejected from the nozzle has passed through the second light beam emitted from the second beam emitting means. The nozzles are used to sequentially eject ink droplets from all the nozzles toward the second light beam in a time-series manner. Each ejection timing at which ink droplets are ejected in the second light beam, and the ejected ink The second method for detecting the form of a droplet
A discharge failure is determined from the detection timing of the beam receiving unit, and both the determination result based on the detection of the first beam receiving unit and the determination result based on the detection of the second beam receiving unit are discharged to the same nozzle. When it is determined that the nozzle is a defective nozzle, or when the determination result when the nozzle is located at a position close to the first or second light receiving unit is determined to be a defective nozzle, the nozzle is specified as a defective nozzle. A method for detecting a discharge failure. 14. A light quantity detection sensitivity associated with a correlation between light receiving distance from a position of said beam receiving means to a position where ink droplets are ejected and light diffraction, wherein a nozzle located at a position close to said first or second beam receiving means. 14. The ejection failure detecting method according to claim 13, wherein the nozzles are located in a range where a predetermined level is maintained. 15. The ejection failure detecting method according to claim 9, wherein the recording head is an inkjet head that performs recording by ejecting ink. 16. The ink-jet head according to claim 1, wherein bubbles are generated in the ink using thermal energy, and the ink is ejected with the generation of the bubbles.
5. A method for detecting a discharge failure according to item 5. 17. The ejection failure detecting method according to claim 9, wherein a textile is used as the recording medium, and printing is performed by ejecting ink droplets onto the textile.