JP2005138460A - Inkjet printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inkjet printer capable of performing normal image recording by preventing ink from curing defects due to variation in ambient humidity. <P>SOLUTION: The inkjet printer 1 comprising a mechanism 3 for carrying a recording medium 99 in a specified carrying direction A, and a carriage 11 movable in the scanning direction B intersecting the carrying direction perpendicularly while mounting recording heads 5, 6, 7 and 8 having nozzles ejecting UV-curing ink toward the recording medium and irradiators 9 and 10 for irradiating ink impacting on the recording medium with UV-rays is further provided with a humidity detector 13 for detecting ambient humidity, and a control section 20 performing switching of the recording mode involving variation in quantity of UV-rays being irradiated from the UV irradiator toward the ink depending on the humidity detected by the humidity detector. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an ink jet printer, and more particularly to an ink jet printer using an ink that is cured by irradiation with ultraviolet rays.

  In recent years, the ink jet recording method can create images more easily and cheaply than the gravure printing method, and thus has been applied to various printing fields such as special printing such as photography, various printing, marking, and color filters. In particular, in the ink jet recording method, an ink jet printer that discharges and controls fine dots, an ink with improved color reproduction range, durability, and discharge suitability, ink absorptivity, color material coloring, and surface gloss. It is also possible to obtain image quality comparable to silver salt photography by combining with special paper that has been improved dramatically.

  In a conventional ink jet printer, a line for performing image recording by ejecting ink from a line head in which a plurality of ejection openings arranged in a direction orthogonal to the transport direction is formed on a recording medium transported in the transport direction. There is a serial method in which image recording is performed by moving a recording head mounted on a carriage in a scanning direction orthogonal to the conveyance direction of the recording medium and ejecting ink from an ejection port of the recording head while the recording head is moving.

Inkjet printers can be classified by ink type. In other words, conventional ink jet printers include a phase change ink jet method using a solid wax ink at room temperature, a solvent ink jet method using an ink mainly composed of a fast-drying organic solvent, and an ultraviolet curable ink that cures when irradiated with ultraviolet light. UV curable ink jet method using Among these, the ultraviolet curable ink jet method is attracting attention because it has a relatively low odor compared to other recording methods, and can be recorded on a recording medium that does not have quick-drying and ink absorbability other than dedicated paper (for example, patents). Reference 1).
JP 2001-310454 A

By the way, conventionally, a cation polymerization type ultraviolet curable ink containing a cation polymerizable compound may be used as an ink used in an ultraviolet curable ink jet type ink jet printer. Since this cationic polymerization type UV curable ink has the property that water becomes a polymerization inhibitor, it becomes difficult for the ink to harden even when irradiated with the same amount of UV light when the ambient humidity is high, resulting in ink curing. Defects may occur.
However, in the conventional ink jet printer, the ink is cured with a certain amount of ultraviolet light capable of curing the ink in a humidity environment within a predetermined range. Insufficient ink curing may occur due to shortage, and there is a possibility that normal image recording cannot be performed.

  SUMMARY OF THE INVENTION An object of the present invention is to provide an ink jet printer that can prevent ink curing failure due to changes in ambient humidity and can perform normal image recording.

The invention described in claim 1
A recording medium transport mechanism for transporting the recording medium in a predetermined transport direction;
A scanning head having a nozzle for ejecting ink that is cured by irradiating ultraviolet rays onto the recording medium, and an ultraviolet irradiating device that irradiates ultraviolet rays to the ink that has landed on the recording medium are mounted, and scanning that is orthogonal to the transport direction. A carriage that can move in any direction,
An inkjet printer comprising:
A humidity detector that detects ambient humidity;
A control unit that switches a recording mode with a change in the amount of ultraviolet light irradiated to the ink from the ultraviolet irradiation device according to the humidity detected by the humidity detection device;
It is characterized by having.

As described above, according to the first aspect of the present invention, the humidity detection device that detects the ambient humidity, and the change in the amount of ultraviolet light applied to the ink from the ultraviolet irradiation device according to the humidity detected by the humidity detection device. Since the recording unit is switched according to the ambient humidity, it is possible to change the amount of ultraviolet light irradiated from the ultraviolet irradiation device to the ink that has landed on the recording medium.
For example, if the ambient humidity is high, the ink is difficult to cure, but in such a case, the recording mode is switched to a result of increasing the amount of ultraviolet light applied to the ink landed on the recording medium.
On the other hand, since the ink is easily cured when the ambient humidity is low, the amount of ultraviolet light necessary for ink curing may be a normal amount of light. In such a case, it is not necessary to increase the amount of ultraviolet light applied to the ink landed on the recording medium, and image recording is performed in a normal recording mode.

The invention according to claim 2 is the inkjet printer according to claim 1,
The recording head has a plurality of nozzles;
The controller is
As the recording mode switching, control is performed to switch the number of nozzles used when recording an image with the same resolution.

  As described above, according to the second aspect of the present invention, the recording head has a plurality of nozzles, and the control unit determines the number of nozzles used when recording an image of the same resolution as the recording mode switching. Since the switching control is performed, the number of pixels recorded in one carriage scan is changed by switching the print mode, and the number of carriage scans necessary for printing an image with the same resolution is changed. As a result, the number of times the ink that has landed on the recording medium is irradiated with ultraviolet rays from the ultraviolet irradiation device also changes, and the amount of ultraviolet rays to be irradiated can be changed.

The invention according to claim 3 is the inkjet printer according to claim 2,
The controller is
When the humidity detected by the humidity detector is high, control is performed to reduce the number of nozzles used when recording an image with the same resolution.

Thus, according to the third aspect of the present invention, when the humidity detected by the humidity detector is high, the control unit reduces the number of nozzles used when recording an image with the same resolution. Since the control is performed, the number of pixels recorded in one carriage scan is decreased, and the number of carriage scans necessary for recording an image with the same resolution is increased. As a result, the number of times the ink that has landed on the recording medium is irradiated with ultraviolet rays from the ultraviolet irradiation device also increases, and the amount of ultraviolet rays to be irradiated can be increased.
For example, in the normal recording mode, in the case of an image having a resolution recorded by one carriage scan using all the nozzles, switching to the recording mode in which the number of nozzles to be used is halved will cause one carriage scan. The number of pixels to be recorded is halved, and two carriage scans are performed to record an image with the same resolution. As a result, the number of times the ultraviolet rays are irradiated from the ultraviolet irradiation device mounted on the carriage is two times, and the ultraviolet rays irradiated from the ultraviolet irradiation device to the ink landed on the recording medium as the number of nozzles used decreases. The amount of light can be increased.
If the recording mode is switched to 1/3 the number of nozzles used, the number of pixels recorded in one carriage scan is reduced to 1/3, and three carriage scans are performed to record an image with the same resolution. Therefore, the number of times the ultraviolet rays are irradiated from the ultraviolet irradiation device is also three times. Furthermore, if the recording mode is switched to ¼ the number of nozzles to be used, the number of pixels recorded in one carriage scan becomes ¼, and four carriage scans are performed in order to record an image with the same resolution. Therefore, the number of times the ultraviolet rays are irradiated from the ultraviolet irradiation device is also four times.

The invention according to claim 4 is the ink jet printer according to claim 1,
The controller is
As the recording mode switching, when an image having the same resolution is recorded, a control is performed in which one nozzle performs switching of a thinning-out amount of pixels to be recorded by one scanning.

  As described above, according to the fourth aspect of the present invention, when the control unit records an image of the same resolution as the switching of the recording mode, the thinning amount of pixels recorded by one nozzle in one scan is set. Since the switching control is performed, the number of pixels recorded in one carriage scan is changed by switching the print mode, and the number of carriage scans necessary for printing an image with the same resolution is changed. As a result, the number of times the ink that has landed on the recording medium is irradiated with ultraviolet rays from the ultraviolet irradiation device also changes, and the amount of ultraviolet rays to be irradiated can be changed.

The invention according to claim 5 is the inkjet printer according to claim 4,
The controller is
When the humidity detected by the humidity detection device is high, control is performed to increase the thinning-out amount of pixels recorded by one nozzle in one scan when recording an image with the same resolution. It is a feature.

As described above, according to the invention described in claim 5, when the humidity detected by the humidity detection device is high, the control unit records one nozzle once when recording an image with the same resolution. Since control for increasing the thinning-out amount of pixels to be recorded by scanning is performed, the number of pixels to be recorded by one carriage scan is decreased, and the number of carriage scans necessary for recording an image having the same resolution is increased. It will be. As a result, the number of times the ink that has landed on the recording medium is irradiated with ultraviolet rays from the ultraviolet irradiation device also increases, and the amount of ultraviolet rays to be irradiated can be increased.
For example, in the normal recording mode, in the case of an image having a resolution that is recorded for all the pixels necessary for one carriage scan, the amount of pixels to be recorded for one carriage scan is adjusted and one carriage is adjusted. When switching to a recording mode in which the number of pixels recorded by scanning is halved, two carriage scans are performed to record an image with the same resolution. As a result, the number of times the ultraviolet rays are irradiated from the ultraviolet irradiation device mounted on the carriage is two times, and the recording medium increases as the thinning amount of pixels recorded by one nozzle in one carriage scan increases. The amount of ultraviolet light irradiated from the ultraviolet irradiation device to the ink that has landed on the ink can be increased.
Note that if the recording mode is switched to a recording mode in which the number of pixels to be recorded in one carriage scan is increased and the number of pixels to be recorded in one carriage scan is reduced to 1/3, an image with the same resolution is recorded. Therefore, since the carriage scanning is performed three times, the number of times the ultraviolet rays are irradiated from the ultraviolet irradiation device is also three. Furthermore, if the number of pixels to be recorded in one carriage scan is further increased to switch to a recording mode in which the number of pixels recorded in one carriage scan is reduced to ¼, an image with the same resolution is recorded. Therefore, since the carriage scanning is performed four times, the number of times the ultraviolet rays are irradiated from the ultraviolet irradiation device is four.

The invention according to claim 6 is the ink jet printer according to claim 1,
The recording head has a plurality of nozzles;
The controller is
As the switching of the recording mode, control is performed to switch the number of nozzles used when recording images of the same resolution and the thinning-out amount of pixels recorded by one nozzle in one scan.

  Thus, according to the sixth aspect of the present invention, the recording head has a plurality of nozzles, and the controller uses the number of nozzles used when recording images of the same resolution as the recording mode switching. Since one nozzle performs control for switching the thinning amount of pixels to be recorded in one scan, various patterns can be set for switching the recording mode. Then, the number of pixels recorded in one carriage scan changes variously by switching the recording mode, and the number of carriage scans necessary for recording an image with the same resolution changes variously. As a result, the number of times the ultraviolet light is irradiated from the ultraviolet irradiation device to the ink that has landed on the recording medium also varies, and the amount of ultraviolet light that is irradiated can be varied.

The invention according to claim 7 is the ink jet printer according to claim 6,
The controller is
When the humidity detected by the humidity detector is high, the number of nozzles used when recording an image with the same resolution is reduced, and thinning out of pixels recorded by one nozzle in one scan is performed. It is characterized by performing control to increase the amount.

Thus, according to the invention described in claim 7, when the humidity detected by the humidity detector is high, the control unit reduces the number of nozzles used when recording an image of the same resolution. In addition, since one nozzle performs control to increase the thinning amount of pixels recorded in one scan, various patterns can be handled when the humidity is high. Then, the number of pixels recorded in one carriage scan decreases in various patterns, and the number of carriage scans necessary to record an image with the same resolution increases in various patterns. As a result, the number of times the ultraviolet light is irradiated from the ultraviolet irradiation device to the ink that has landed on the recording medium also increases in various patterns, and the amount of irradiated ultraviolet light can be increased in various patterns.
For example, in the normal recording mode, in the case of an image having a resolution that records all pixels necessary for one carriage scan using all nozzles, the number of nozzles used is halved and When the thinning amount of pixels recorded by carriage scanning is adjusted to switch to a recording mode in which the number of pixels recorded by one carriage scanning is halved, the number of pixels recorded by one carriage scanning is one. / 4, and four carriage scans are performed to record an image with the same resolution. As a result, the number of times the ultraviolet ray is irradiated from the ultraviolet ray irradiation device mounted on the carriage is four times, the number of nozzles to be used is reduced, and the thinning amount of pixels recorded by one nozzle in one carriage scan is increased. Accordingly, the amount of ultraviolet light irradiated from the ultraviolet irradiation device to the ink landed on the recording medium can be increased.
A recording mode in which the number of nozzles to be used is halved and the number of pixels to be recorded in one carriage scan is increased so that the number of pixels recorded in one carriage scan is ３. , The number of pixels recorded in one carriage scan is reduced to 1/6, and six carriage scans are performed to record an image with the same resolution. The number of times to be played is also six. Furthermore, the recording mode is set to reduce the number of nozzles to be used to 1/3 and increase the thinning amount of pixels to be recorded in one carriage scan so that the number of pixels to be recorded in one carriage scan is 1/3. If switched, the number of pixels recorded in one carriage scan becomes 1/9, and nine carriage scans are performed to record an image of the same resolution. The number of times is 9 times.

According to the first aspect of the present invention, the amount of ultraviolet light irradiated from the ultraviolet irradiation device to the ink landed on the recording medium can be changed by switching the recording mode according to the ambient humidity. When the ambient humidity is high, switching to a recording mode that results in an increase in the amount of ultraviolet light applied to the ink that has landed on the recording medium can prevent ink curing failure and perform normal image recording. .
In addition, when the ambient humidity is low, image recording is performed in a normal recording mode in which the amount of ultraviolet light applied to the ink landed on the recording medium is a normal amount of light, thereby eliminating extra work and time. An image can be quickly recorded on a recording medium, and as a result, productivity when recording an image on the recording medium can be improved.

  According to the second and third aspects of the invention, by changing the number of nozzles to be used, the number of times the ultraviolet rays are irradiated from the ultraviolet irradiation device to the ink landed on the recording medium can be changed to change the amount of ultraviolet light. For example, when the ambient humidity is high, the number of nozzles to be used is reduced to increase the number of times the ultraviolet light is irradiated from the ultraviolet irradiation device to the ink landed on the recording medium, thereby increasing the amount of ultraviolet light. As a result, ink curing failure can be prevented and normal image recording can be performed.

  According to the fourth and fifth aspects of the present invention, the ink that has landed on the recording medium is irradiated with ultraviolet rays from the ultraviolet irradiation device by switching the thinning-out amount of pixels recorded by one nozzle in one scan. The amount of ultraviolet light can be changed by changing the number of times. For example, when the ambient humidity is high, the recording medium can be obtained by increasing the thinning-out amount of pixels recorded by one nozzle in one scan. It is possible to increase the number of times the ultraviolet light is irradiated from the ultraviolet irradiation device to the ink landed on the ink, thereby increasing the amount of ultraviolet light. As a result, it is possible to prevent ink curing failure and perform normal image recording.

  According to the sixth and seventh aspects of the invention, the number of nozzles to be used and the thinning amount of pixels to be recorded in one scan by one nozzle are switched, so that the ink that has landed on the recording medium is changed from the ultraviolet irradiation device. For example, when the ambient humidity is high, the number of nozzles used is reduced, and one nozzle is used once because the number of times of irradiation with ultraviolet rays can be changed to change the amount of ultraviolet rays. By increasing the thinning amount of pixels to be recorded in this scanning, the number of times the ultraviolet rays are irradiated from the ultraviolet irradiation device to the ink landed on the recording medium is increased in various patterns, and the amount of ultraviolet light is increased in various patterns. As a result, ink curing failure can be prevented with various patterns and normal image recording can be performed.

  Hereinafter, embodiments of an inkjet printer according to the present invention will be described with reference to the drawings. However, the scope of the invention is not limited to the illustrated examples.

  FIG. 1 is a diagram illustrating a schematic configuration of an ink jet printer according to an embodiment of the present invention, and FIG. 2 is a control block diagram illustrating a main control configuration of the ink jet printer according to the present embodiment.

  As shown in FIG. 1, the ink jet printer 1 is a serial type ink jet printer, and includes a flat platen 2 that supports a non-recording surface on the back side of a recording surface of a recording medium 99. Conveying rollers 3a and 3b of the recording medium conveying mechanism 3 are disposed before and after the platen 2, respectively. The conveying rollers 3a and 3b are coupled by a conveying belt 3c and rotate in a predetermined direction around the axis before and after the platen 2, and the recording medium 99 is conveyed along with the rotation of the conveying rollers 3a and 3b. It is conveyed along the direction A.

  Above the platen 2, an image recording unit 4 that records an image on the recording surface of the recording medium 99 is disposed. The image recording unit 4 includes a guide member 12 extending in a direction orthogonal to the conveyance direction A (hereinafter referred to as “scanning direction B”), and a carriage 11 is supported on the guide member 12. The carriage 11 is reciprocally movable along the scanning direction B while being guided by the guide member 12 by driving of the carriage driving mechanism 11a.

  Four recording heads 5 and 6 eject inks of process colors of yellow (Y), magenta (M), cyan (C), and black (K) toward the recording surface of the recording medium 99 on the carriage 11, respectively. , 7 and 8 are mounted, and the four recording heads 5, 6, 7 and 8 can be simultaneously moved by the reciprocating movement of the carriage 11. In this embodiment, the recording head 5 discharges yellow ink, the recording head 6 discharges magenta ink, the recording head 7 discharges cyan ink, and the recording head 8 discharges black ink.

  As shown in FIGS. 3 to 7, a plurality of nozzles 5a,... For ejecting ink as droplets are arranged on the side of the recording head 5 that ejects yellow ink that faces the recording surface of the recording medium 99. It is installed. The plurality of nozzles 5a,... Are arranged along the conveyance direction A of the recording medium 99 to form a nozzle row 5b, and face the recording surface of the recording medium 99 in the recording head 5 having the ejection openings of the nozzles 5a. The surface to be used is the nozzle surface 5c.

  3 to 7, for the sake of convenience, only the yellow recording head 5 and the ultraviolet irradiation device 9 or the ultraviolet irradiation device 10 to be described later are shown. However, as shown in FIG. Other recording heads 6, 7 and 8 are also mounted adjacent to the recording head 5, and the carriage 11 has an ultraviolet irradiation device 9 mounted on the left end thereof and an ultraviolet irradiation device 10 mounted on the right end thereof. Both are provided. Further, it is assumed that a plurality of nozzles, nozzle rows, nozzle surfaces, and the like provided in the yellow recording head 5 are also provided in the other recording heads 6, 7, and 8. Hereinafter, the configuration, control, operation, and the like described for the yellow recording head 5 are also applied to the other recording heads 6, 7, and 8.

  Further, each of the recording heads 5, 6, 7, and 8 of the present embodiment scans the carriage 11 from one end to the other end in the scanning direction B of the recording medium 99 (hereinafter referred to as one scanning of the carriage 11). It is possible to switch the number of nozzles used for ink ejection at the time. For example, when all nozzles are used, when every other nozzle is used and half of all nozzles are used, every other nozzle is used and every third nozzle is used. In this case, switching is possible, for example, when every third nozzle is used and 1/4 of all nozzles are used.

  Further, in the present embodiment, the thinning amount of pixels recorded by one nozzle of each of the recording heads 5, 6, 7, and 8 is switched during one scanning of the carriage 11 by the control of the control unit 20 described later. It is possible. In other words, it is possible to switch the number of pixels from which one nozzle of each recording head 5, 6, 7, 8 ejects ink in the scanning direction B during one scan of the carriage 11. For example, when ink is ejected to all pixels in the scanning direction B, every other pixel in the scanning direction B is ejected, and when ink is ejected to half of all the pixels in the scanning direction B, scanning is performed. When ink is ejected every two pixels in the direction B and ink is ejected to one third of all the pixels in the scanning direction B, ink is ejected every three pixels in the scanning direction B and the scanning direction B It is possible to switch when, for example, ink is ejected to 1/4 of all the pixels.

  Furthermore, in the present embodiment, the number of nozzles used for ink ejection of the recording heads 5, 6, 7, and 8 during one scan of the carriage 11 and the one scan of the carriage 11 are changed. It is possible to switch both the thinning-out amounts of pixels recorded by one nozzle of each of the recording heads 5, 6, 7, and 8 at the same time, or to switch only one of them.

  Further, as described above, the ultraviolet irradiation devices 9 and 10 for irradiating the ink landed on the recording medium 99 with ultraviolet rays are mounted on both ends in the scanning direction B of the carriage 11, respectively. Similar to the recording heads 5, 6, 7, 8, the carriage 11 can be moved by reciprocating movement. Each ultraviolet irradiation device 9, 10 is provided with an ultraviolet light source (not shown), and each ultraviolet irradiation device 9, 10 emits ultraviolet light toward the recording surface of the recording medium 99 when the ultraviolet light source is turned on. Can be irradiated. As the ultraviolet light source, a high pressure mercury lamp, a low pressure mercury lamp, a metal halide lamp, a black light, a hot cathode tube, a cold cathode tube, an LED (Light Emitting Diode), or the like is applied.

  In addition, a humidity sensor 13 is provided at a predetermined position of the inkjet printer 1 as a humidity detection device that detects ambient humidity. In the present embodiment, the humidity sensor 13 is disposed at a position where the platen 2 does not contact the recording medium 99, and detects the humidity in the vicinity of the recording medium 99 every predetermined period or at all times. The detected humidity is transmitted as information to the control unit 20. The position at which the humidity sensor 13 is disposed is not limited to the platen 2 described above. For example, the humidity sensor 13 may be disposed at a predetermined position of the carriage 11.

Next, the control configuration in the present embodiment will be described with reference to FIG.
In the present embodiment, the inkjet printer 1 is provided with a control unit 20 that controls each drive unit, as shown in FIG. The control unit 20 includes a CPU 21, a RAM 22, a ROM 23, and the like. The control unit 20 is connected to the recording medium transport mechanism 3, the recording heads 5, 6, 7, 8 and ultraviolet rays via an interface (not shown). The devices 9 and 10, the carriage drive mechanism 11a, the humidity sensor 13 for detecting the humidity in the vicinity of the recording medium 99, and the input unit 14 for inputting an instruction at the time of image recording such as the type of the recording medium 99 are electrically connected. Yes. In addition to the above, each drive unit of the inkjet printer 1 is connected to the control unit 20.

The control unit 20 reciprocates the carriage 11 in the scanning direction B and repeats conveyance and stop of the recording medium 99 in accordance with the operation of the carriage 11 so that the recording medium 99 is intermittently conveyed in the conveyance direction A. The operation of the carriage drive mechanism 11a and the recording medium transport mechanism 3 is controlled.
The control unit 20 controls the ultraviolet irradiation devices 9 and 10 to generate ultraviolet rays.

  Further, the control unit 20 is connected to an input unit 14 and a recording head 5, 6, 7, 8 including a host computer and a scanner for inputting image information, a keyboard for inputting image recording conditions, and the like. Is configured to operate the recording heads 5, 6, 7 and 8 on the basis of a predetermined signal input from the input unit 14 and to eject a ink onto the recording medium 99 to record a predetermined image.

Further, the control unit 20 receives the humidity in the vicinity of the recording medium 99 detected by the humidity sensor 13 as information, and in response to this, recording accompanied by a change in the amount of ultraviolet light applied to the ink from the ultraviolet irradiation devices 9 and 10. Controls to switch modes. As the recording mode switching control, when performing control for switching the number of nozzles used when recording an image with the same resolution, or when recording an image with the same resolution, one nozzle records pixels in one scan. There is a case where control for switching the thinning-out amount is performed. In some cases, both the number of nozzles to be used and the thinning-out amount of pixels are simultaneously switched.
Hereinafter, the control of the recording head 5 that discharges yellow ink will be described in detail as an example. Note that the control example described for the recording head 5 is also applied to the other recording heads 6, 7, and 8. When a color image is actually recorded, each recording head 5, 6, 7 is used. , 8 are controlled simultaneously.

  For example, first, when an image with a predetermined resolution is recorded, a normal time when the ambient humidity is equal to or lower than a predetermined high humidity reference value (for example, when the absolute humidity is 0.015 g / g). The control unit 20 controls to perform image recording in the normal recording mode. Specifically, as shown in FIG. 3, among a plurality of nozzles 5a,... Constituting the nozzle row 5b arranged along the conveyance direction A of the recording medium 99, it is necessary for recording an image of the resolution. All the nozzles are used, and ink is ejected to all the pixels in the scanning direction B by one scanning B1 of the carriage 11 from the left end to the right end of the recording medium 99 in the scanning direction B. Thereby, as indicated by a white circle D1 in FIG. 3, an image G having a predetermined resolution in a range where ink is ejected by the recording head 5 can be recorded by one scan B1 of the carriage 11. In this case, since the carriage 11 is scanned only once for the image recording in the range, the number of times the ultraviolet rays are irradiated from the ultraviolet irradiation device mounted on the carriage 11 is also one.

  On the other hand, when recording an image having a predetermined resolution, the ink is difficult to cure at the first high humidity when the ambient humidity is higher than the first reference value of the high humidity. Control is performed so that image recording is performed in a recording mode in a wet state. Specifically, as shown in FIG. 4 (a), a plurality of nozzles 5a,... Constituting the nozzle row 5b arranged along the transport direction A of the recording medium 99 are used every other one. Control is performed so that half of all the nozzles necessary for recording a resolution image are used. At this time, for the pixels in the scanning direction B, ink is ejected to all the pixels. As a result, as indicated by a white circle D2 in the upper diagram of FIG. 4A, ink is ejected by the recording head 5 in the first scanning B1 of the carriage 11 from the left end to the right end in the scanning direction B of the recording medium 99. In this range, an image having a half of a predetermined resolution can be recorded, and the state shown in the upper diagram of FIG.

Next, the second scanning B2 of the carriage 11 from the right end to the left end in the scanning direction B of the recording medium 99 is performed using 1/2 nozzles as shown in the lower diagram of FIG. As indicated by a black circle D3, the remaining half of the image having a predetermined resolution in the range where ink is ejected by the recording head 5 is recorded. As a result, as shown in the lower diagram of FIG. 4B, an image G having a predetermined resolution similar to the image G recorded in the normal recording mode is recorded.
In this case, since the carriage 11 is scanned twice with respect to the image recording in the range, the number of times of irradiation with ultraviolet rays from the ultraviolet irradiation device mounted on the carriage 11 is also two. As a result, the amount of ultraviolet light irradiated from the ultraviolet irradiation device to the ink landed on the recording medium 99 can be increased.

  Further, when recording an image with a predetermined resolution, image recording may be performed as follows when the ambient humidity is high due to the high humidity first reference value. That is, as shown in FIG. 5A, the carriage 11 is adjusted by adjusting the thinning amount so that every other pixel to be recorded in the scanning direction B by one nozzle 5a in one scanning of the carriage 11 is thinned out. Control is performed so that the number of pixels recorded in one scan is halved. At this time, for the plurality of nozzles 5a,... Constituting the nozzle row 5b arranged along the transport direction A, all necessary nozzles are used. As a result, as indicated by a white circle D4 in the upper diagram of FIG. 5A, ink is ejected by the recording head 5 in the first scanning B1 of the carriage 11 from the left end to the right end in the scanning direction B of the recording medium 99. In this range, an image having a half of a predetermined resolution can be recorded, resulting in a state as shown in the upper diagram of FIG.

Next, as shown in the lower diagram of FIG. 5A, the second scan B2 of the carriage 11 from the right end to the left end in the scanning direction B of the recording medium 99 is performed to fill the thinned pixels, and the black circle D5 As shown in the diagram, the remaining half of the image having a predetermined resolution in the range where ink is ejected by the recording head 5 is recorded. As a result, as shown in the lower diagram of FIG. 5B, an image G having a predetermined resolution similar to the image G recorded in the normal recording mode is recorded.
Also in this case, since the carriage 11 is scanned twice with respect to the image recording in the range, from the ultraviolet irradiation device mounted on the carriage 11 as in the case where the number of nozzles to be used is halved. The number of times of irradiation with ultraviolet rays is two. As a result, the amount of ultraviolet light irradiated from the ultraviolet irradiation device to the ink landed on the recording medium 99 can be increased.

  Further, when recording an image with a predetermined resolution, a high humidity second reference value in which the ambient humidity exceeds the high humidity first reference value (for example, when the absolute humidity is 0.018 g / g). At higher second high humidity, the ink is more difficult to cure than at the first high humidity, so that the control unit 20 increases the amount of ultraviolet light applied to the ink from the first high humidity. Control is performed to perform image recording in the recording mode. Specifically, as shown in FIG. 6A, the thinning amount is adjusted so that one nozzle 5a records every two pixels in the scanning direction B in one scan of the carriage 11. And the number of pixels recorded in one scan of the carriage 11 is controlled to 1/3. At this time, for the plurality of nozzles 5a,... Constituting the nozzle row 5b arranged along the transport direction A, all necessary nozzles are used. As a result, as indicated by the white circle D6 in the upper diagram of FIG. 6A, ink is ejected by the recording head 5 in the first scanning B1 of the carriage 11 from the left end to the right end in the scanning direction B of the recording medium 99. 1/3 of a predetermined resolution in the above range can be recorded, resulting in a state as shown in the upper diagram of FIG.

  Next, a second scan B2 of the carriage 11 from the right end to the left end in the scanning direction B of the recording medium 99 is performed so as to fill one of the thinned pixels, as shown in the middle diagram of FIG. As shown by a black circle D7, an image of 1/3 of the remaining of the predetermined resolution in the range where ink is ejected by the recording head 5 is recorded. As a result, the state shown in the middle diagram of FIG.

Next, the third scan B3 of the carriage 11 from the left end to the right end in the scanning direction B of the recording medium 99 is performed as shown in the lower diagram of FIG. As shown by a horizontal stripe circle D8, an image of the remaining 1/3 of a predetermined resolution in a range where ink is ejected by the recording head 5 is recorded. As a result, as shown in the lower diagram of FIG. 6B, an image G having a predetermined resolution similar to the image G recorded in the normal recording mode is recorded.
In this case, since the carriage 11 is scanned three times for image recording in the range, the number of times the ultraviolet rays are irradiated from the ultraviolet irradiation device mounted on the carriage 11 is also three. As a result, the amount of ultraviolet light irradiated from the ultraviolet irradiation device to the ink landed on the recording medium 99 can be further increased.

  Further, when recording an image with a predetermined resolution, a high humidity third reference value in which the ambient humidity exceeds the high humidity second reference value (for example, when the absolute humidity is 0.02 g / g). At higher third high humidity, the ink is more difficult to cure than at the second high humidity, so that the control unit 20 increases the amount of ultraviolet light applied to the ink from the second high humidity. Control is performed to perform image recording in the recording mode. Specifically, as shown in FIG. 7 (a), a plurality of nozzles 5a,... Constituting the nozzle row 5b arranged along the transport direction A of the recording medium 99 are used every other one. Half of all the nozzles necessary for recording a resolution image are used, and every other pixel that one nozzle 5a records in the scanning direction B is thinned out by one scan of the carriage 11. In this way, the thinning amount is adjusted so that the number of pixels recorded by one nozzle 5a in one scan of the carriage 11 is halved. As a result, the number of pixels recorded by one scan of the carriage 11 is controlled to be ¼. As a result, as indicated by the white circle D9 in the top diagram of FIG. 7A, the recording head 5 performs the first scanning B1 of the carriage 11 from the left end to the right end in the scanning direction B of the recording medium 99. A 1/4 image of a predetermined resolution in the ink ejected range can be recorded, and a 1/4 image as shown in the top diagram of FIG. 7B is recorded. .

  Next, the second scan B2 of the carriage 11 from the right end to the left end in the scanning direction B of the recording medium 99 as shown in the second diagram from the top in FIG. As shown by a black circle D10, a quarter of the remaining image having a predetermined resolution in the range where ink is ejected by the recording head 5 is recorded. As a result, a 2/4 image as shown in the second diagram from the top in FIG. 7B is recorded.

  Next, using the remaining 1/2 nozzles, as shown in the third diagram from the top in FIG. 7A, 3 of the carriage 11 from the left end to the right end in the scanning direction B of the recording medium 99 is used. A second scan B3 is performed, and as shown by a horizontal stripe circle D11, an image of a quarter of the remainder of the predetermined resolution in the range ejected by the recording head 5 is recorded. As a result, a 3/4 image as shown in the third figure from the top in FIG. 7B is recorded.

Next, the fourth scan B4 of the carriage 11 from the right end to the left end in the scanning direction B of the recording medium 99 is performed as shown in the bottom diagram of FIG. Then, as indicated by the vertical stripes D12, the remaining 1/4 image of the predetermined resolution in the range where ink is ejected by the recording head 5 is recorded. As a result, as shown in the bottom diagram of FIG. 7B, an image G having a predetermined resolution similar to the image G recorded in the normal recording mode is recorded.
In this case, since the carriage 11 is scanned four times for image recording in the range, the number of times the ultraviolet rays are irradiated from the ultraviolet irradiation device mounted on the carriage 11 is also four times. As a result, the amount of ultraviolet light irradiated from the ultraviolet irradiation device to the ink landed on the recording medium 99 can be further increased.

By performing such control, the ink can be irradiated with an ultraviolet light amount corresponding to the ambient humidity with simple control.
It should be noted that the humidity reference value for switching the recording mode may be set to an appropriate number of 1 or more as necessary.
Also, the recording mode switching pattern is not limited to the above-described pattern, and may be set appropriately.

Next, “ink” used in the present embodiment will be described.
The ink used in the present embodiment is an ultraviolet curable ink that is cured by irradiation with ultraviolet rays as light, and includes as a main component a polymerizable compound (including known polymerizable compounds), a photoinitiator, and a color. It contains at least a material.

  The ultraviolet curable ink is roughly classified into a radical polymerization ink containing a radical polymerizable compound and a cationic polymerization ink containing a cationic polymerizable compound as a polymerizable compound. A cationic polymerization type ink is applicable. Note that the cationic polymerization ink has higher sensitivity to ultraviolet rays and less inhibition of the polymerization reaction by oxygen than the radical polymerization ink, and can reduce the illuminance necessary for curing the ink. In addition, since the cationic polymerization type ink has a characteristic that water becomes a polymerization inhibitor, the ink is difficult to be cured even when irradiated with the same amount of ultraviolet light when the ambient humidity is high.

Next, the operation of the ink jet printer 1 in the present embodiment will be described.
When an operator sets the recording medium 99 in the ink jet printer 1 and the power of the ink jet printer 1 is turned on, the ultraviolet light source is turned on to irradiate ultraviolet rays toward the recording surface of the recording medium 99 on which ink droplets land. To do.

When image information is sent from the input unit 14 to the control unit 20 of the inkjet printer 1 and setting information for various image recording conditions is sent, the control unit 20 starts image recording.
During the operation of the ink jet printer 1, on the other hand, the transport rollers 3 a and 3 b are operated and rotated, and the recording medium 99 is transported in the transport direction A from the rear to the front with the non-recording surface supported by the platen 2. It is conveyed along. On the other hand, the carriage 11 is operated to reciprocate along the scanning direction B immediately above the recording medium 99, and the four recording heads 5, 6, 7, 8 and the two ultraviolet irradiation devices 9 mounted on the carriage 11. , 10 also move as the carriage 11 reciprocates.

  During the movement of the carriage 11, the four recording heads 5, 6, 7, and 8 eject ink from the nozzles toward the recording surface of the recording medium 99, and the two ultraviolet irradiation devices 9 and 10 include the recording medium 99. Irradiate ultraviolet rays toward the recording surface. In this embodiment, since the respective ultraviolet light sources of the two ultraviolet irradiation devices 9 and 10 are always in the on state, the ink ejected from the respective recording heads 5, 6, 7, and 8 Immediately after landing on the recording medium 99 by the ultraviolet irradiation device on the downstream side of the recording heads 5, 6, 7, and 8 with respect to the moving direction, the ultraviolet rays are irradiated and cured immediately. Further, since the carriage 11 is reciprocated, the ultraviolet rays are irradiated a plurality of times from the two ultraviolet irradiation devices 9 and 10 to the same portion, so that the ink is reliably fixed on the recording surface of the recording medium 99.

  Thereafter, the inkjet printer 1 repeats the above operations, and a desired image composed of a plurality of dots of each process color is sequentially recorded on the recording surface of the recording medium 99.

  Here, in the ink jet printer 1 of the present embodiment, the humidity sensor 13 detects the humidity in the vicinity of the recording medium 99 every predetermined period or at all times. The detected humidity is transmitted to the control unit 20 as information, and the recording mode is switched according to the humidity near the recording medium 99 by the control of the control unit 20 that has received the information. As the recording mode is switched, the number of times the ultraviolet rays are irradiated from the ultraviolet irradiation devices 9 and 10 onto the ink on the recording medium 99 changes. The amount of ultraviolet light applied to the upper ink changes.

For example, when an image with a predetermined resolution is recorded, a first reference value for high humidity is determined in advance as a case where the absolute humidity is 0.015 g / g, and a second reference value for high humidity that further increases the humidity is absolute. It is determined that the humidity is 0.018 g / g, and the third reference value of high humidity that further increases the humidity is determined as the case where the absolute humidity is 0.02 g / g.
When the humidity detected by the humidity sensor 13 is 0.015 g / g or less, which is equal to or lower than the first reference value for high humidity, image recording is performed in the normal recording mode. In this normal recording mode, all the nozzles necessary for recording an image with a predetermined resolution are used, and one scan is performed by the carriage 11 from the left end to the right end in the scanning direction B of the recording medium 99. These nozzles discharge ink to all the pixels without thinning out the pixels to be recorded in the scanning direction B. As a result, an image in the range where ink is ejected is recorded by one scan of the carriage 11. As a result, the number of times the ultraviolet rays are irradiated from the ultraviolet irradiation device mounted on the carriage 11 is one.

  In addition, at the first high humidity when the humidity detected by the humidity sensor 13 is higher than 0.015 g / g which is the first reference value of high humidity and not more than 0.018 g / g which is the second reference value of high humidity, the ink Since it becomes difficult to cure, image recording is performed by switching the recording mode to the recording mode at the time of the first high humidity. In the recording mode at the time of the first high humidity, half of all the nozzles necessary for recording an image with a predetermined resolution are used, and from the left end to the right end in the scanning direction B of the recording medium 99 or In one scan of the carriage 11 from the right end to the left end, one nozzle discharges ink to all the pixels without thinning out the pixels recorded in the scanning direction B. As a result, it is possible to record an image with a half of a predetermined resolution in the range where ink is ejected by one scan of the carriage 11, and the image of the range where ink is ejected is recorded by two scans of the carriage 11. Is done. As a result, the number of times the ultraviolet rays are irradiated from the ultraviolet irradiation device mounted on the carriage 11 is two.

  In the first high humidity recording mode, all the nozzles necessary for recording an image with a predetermined resolution are used, and from the left end to the right end in the scanning direction B of the recording medium 99 or from the right end to the left end. Alternatively, a pattern in which one nozzle thins out half of all the pixels recorded in the scanning direction B in one scan of the carriage 11 and ejects ink to 1/2 pixels. Also by this, it is possible to record an image having a half of a predetermined resolution in a range where ink is ejected by one scan of the carriage 11, and an image in the range where ink is ejected is scanned twice by the carriage 11. Will be recorded. As a result, the number of times the ultraviolet rays are irradiated from the ultraviolet irradiation device mounted on the carriage 11 is two.

  Furthermore, at the time of the second high humidity when the humidity detected by the humidity sensor 13 is higher than 0.018 g / g which is the second reference value of high humidity and not more than 0.02 g / g which is the third reference value of high humidity, Since the ink is difficult to cure, the recording mode is switched to the recording mode at the second high humidity to perform image recording. In this second high humidity recording mode, all the nozzles necessary for recording an image of a predetermined resolution are used, and the carriage from the left end to the right end or the right end to the left end in the scanning direction B of the recording medium 99 is used. In one scan of 11, one nozzle thins out 2/3 of all the pixels recorded in the scanning direction B and ejects ink to 1/3 of the pixels. As a result, an image of 1/3 of a predetermined resolution in the range in which ink is ejected by one scan of the carriage 11 can be recorded, and the image in the range in which ink is ejected is recorded by three scans of the carriage 11. Is done. As a result, the number of times the ultraviolet rays are irradiated from the ultraviolet irradiation device mounted on the carriage 11 is three times.

  Furthermore, when the humidity detected by the humidity sensor 13 is higher than 0.02 g / g, which is the third reference value for high humidity, the ink is more difficult to cure, so the recording mode is set to the third high humidity. The image recording is performed by switching to the current recording mode. In the recording mode at the time of the third high humidity, half of all the nozzles necessary for recording an image with a predetermined resolution are used, and from the left end to the right end in the scanning direction B of the recording medium 99 or In one scan of the carriage 11 from the right end to the left end, one nozzle thins out 1/2 of all the pixels recorded in the scanning direction B, and ejects ink to 1/2 pixels. As a result, an image having a predetermined resolution in a range in which ink is ejected by one scan of the carriage 11 can be recorded, and an image in the range in which ink is ejected is recorded by four scans of the carriage 11. Is done. As a result, the number of times the ultraviolet rays are irradiated from the ultraviolet irradiation device mounted on the carriage 11 is four.

  In this embodiment, the timing for switching the recording mode in accordance with the humidity detected by the humidity sensor 13 is determined at the start of image recording in accordance with the humidity at that time, and then the humidity during image recording. The recording mode is not switched until the image recording is completed even if the value changes, but the present invention is not limited to this. For example, when the humidity changes, the recording mode is switched correspondingly even during image recording. It is also possible that

  As described above, according to the ink jet printer of the present embodiment, the humidity detection device that detects the ambient humidity, and the amount of ultraviolet light that is applied to the ink from the ultraviolet irradiation device according to the humidity detected by the humidity detection device. And a control unit that switches the recording mode with change, so that the amount of ultraviolet light irradiated from the ultraviolet irradiation device to the ink that has landed on the recording medium can be changed by switching the recording mode according to the ambient humidity. it can.

For example, if the ambient humidity is high, the ink is difficult to cure, but in such a case, the recording mode is switched to a result of increasing the amount of ultraviolet light applied to the ink landed on the recording medium. As a result, ink curing failure can be prevented and normal image recording can be performed.
On the other hand, since the ink is easily cured when the ambient humidity is low, the amount of ultraviolet light necessary for ink curing may be a normal amount of light. In such a case, it is not necessary to increase the amount of ultraviolet light applied to the ink landed on the recording medium, and image recording is performed in a normal recording mode. As a result, an extra work and time can be saved, and an image can be recorded on the recording medium earlier, and productivity when recording an image on the recording medium can be improved.

In the present embodiment, the recording head has a plurality of nozzles, and the control unit performs control to switch the number of nozzles used when recording an image with the same resolution as the recording mode switching. By switching the recording mode, the number of pixels recorded in one carriage scan changes, and the number of carriage scans necessary to record an image with the same resolution changes. As a result, the number of times the ink that has landed on the recording medium is irradiated with ultraviolet rays from the ultraviolet irradiation device also changes, and the amount of ultraviolet rays to be irradiated can be changed.
Specifically, when the humidity detected by the humidity detection device is high, the control unit performs control to reduce the number of nozzles used when recording an image with the same resolution. The number of pixels recorded by scanning decreases, and the number of carriage scans necessary to record an image with the same resolution increases. As a result, the number of times the ink that has landed on the recording medium is irradiated with ultraviolet rays from the ultraviolet irradiation device also increases, and the amount of ultraviolet rays to be irradiated can be increased.

For example, in the normal recording mode, in the case of an image having a resolution recorded by one carriage scan using all the nozzles, switching to the recording mode in which the number of nozzles to be used is halved will cause one carriage scan. The number of pixels to be recorded is halved, and two carriage scans are performed to record an image with the same resolution. As a result, the number of times the ultraviolet rays are irradiated from the ultraviolet irradiation device mounted on the carriage is two times, and the ultraviolet rays irradiated from the ultraviolet irradiation device to the ink landed on the recording medium as the number of nozzles used decreases. The amount of light can be increased.
If the recording mode is switched to 1/3 the number of nozzles used, the number of pixels recorded in one carriage scan is reduced to 1/3, and three carriage scans are performed to record an image with the same resolution. Therefore, the number of times the ultraviolet rays are irradiated from the ultraviolet irradiation device is also three times. Furthermore, if the recording mode is switched to ¼ the number of nozzles to be used, the number of pixels recorded in one carriage scan becomes ¼, and four carriage scans are performed in order to record an image with the same resolution. Therefore, the number of times the ultraviolet rays are irradiated from the ultraviolet irradiation device is also four times.
As a result, ink curing failure can be prevented and normal image recording can be performed.

Furthermore, in the present embodiment, the control unit performs control for switching the thinning amount of pixels recorded by one nozzle in one scan when recording images of the same resolution as the recording mode switching. By switching the recording mode, the number of pixels recorded in one carriage scan changes, and the number of carriage scans necessary to record an image with the same resolution changes. As a result, the number of times the ink that has landed on the recording medium is irradiated with ultraviolet rays from the ultraviolet irradiation device also changes, and the amount of ultraviolet rays to be irradiated can be changed.
Specifically, when the humidity detected by the humidity detector is high, the controller thins out pixels that one nozzle records in one scan when recording an image with the same resolution. Therefore, the number of pixels recorded in one carriage scan decreases, and the number of carriage scans necessary to record an image with the same resolution increases. As a result, the number of times the ink that has landed on the recording medium is irradiated with ultraviolet rays from the ultraviolet irradiation device also increases, and the amount of ultraviolet rays to be irradiated can be increased.

For example, in the normal recording mode, in the case of an image having a resolution that is recorded for all the pixels necessary for one carriage scan, the amount of pixels to be recorded for one carriage scan is adjusted and one carriage is adjusted. When switching to a recording mode in which the number of pixels recorded by scanning is halved, two carriage scans are performed to record an image with the same resolution. As a result, the number of times the ultraviolet rays are irradiated from the ultraviolet irradiation device mounted on the carriage is two times, and the recording medium increases as the thinning amount of pixels recorded by one nozzle in one carriage scan increases. The amount of ultraviolet light irradiated from the ultraviolet irradiation device to the ink that has landed on the ink can be increased.
Note that if the recording mode is switched to a recording mode in which the number of pixels to be recorded in one carriage scan is increased and the number of pixels to be recorded in one carriage scan is reduced to 1/3, an image with the same resolution is recorded. Therefore, since the carriage scanning is performed three times, the number of times the ultraviolet rays are irradiated from the ultraviolet irradiation device is also three. Furthermore, if the number of pixels to be recorded in one carriage scan is further increased to switch to a recording mode in which the number of pixels recorded in one carriage scan is reduced to ¼, an image with the same resolution is recorded. Therefore, since the carriage scanning is performed four times, the number of times the ultraviolet rays are irradiated from the ultraviolet irradiation device is four.
As a result, ink curing failure can be prevented and normal image recording can be performed.

Furthermore, in the present embodiment, the recording head has a plurality of nozzles, and the control unit switches the recording mode so that the number of nozzles used when recording images of the same resolution and one nozzle is one. Since control is performed to switch the thinning-out amount of pixels to be recorded in one scan, various patterns can be set for switching the recording mode. Then, the number of pixels recorded in one carriage scan changes variously by switching the recording mode, and the number of carriage scans necessary for recording an image with the same resolution changes variously. As a result, the number of times the ultraviolet light is irradiated from the ultraviolet irradiation device to the ink that has landed on the recording medium also varies, and the amount of ultraviolet light that is irradiated can be varied.
Specifically, when the humidity detected by the humidity detector is high, the control unit reduces the number of nozzles used when recording an image with the same resolution, and one nozzle is used once. Since control is performed to increase the thinning amount of pixels to be recorded by scanning, various patterns can be used when the humidity is high. Then, the number of pixels recorded in one carriage scan decreases in various patterns, and the number of carriage scans necessary to record an image with the same resolution increases in various patterns. As a result, the number of times the ultraviolet light is irradiated from the ultraviolet irradiation device to the ink that has landed on the recording medium also increases in various patterns, and the amount of irradiated ultraviolet light can be increased in various patterns.

For example, in the normal recording mode, in the case of an image having a resolution that records all pixels necessary for one carriage scan using all nozzles, the number of nozzles used is halved and When the thinning amount of pixels recorded by carriage scanning is adjusted to switch to a recording mode in which the number of pixels recorded by one carriage scanning is halved, the number of pixels recorded by one carriage scanning is one. / 4, and four carriage scans are performed to record an image with the same resolution. As a result, the number of times the ultraviolet ray is irradiated from the ultraviolet ray irradiation device mounted on the carriage is four times, the number of nozzles to be used is reduced, and the thinning amount of pixels recorded by one nozzle in one carriage scan is increased. Accordingly, the amount of ultraviolet light irradiated from the ultraviolet irradiation device to the ink landed on the recording medium can be increased.
A recording mode in which the number of nozzles to be used is halved and the number of pixels to be recorded in one carriage scan is increased so that the number of pixels recorded in one carriage scan is ３. , The number of pixels recorded in one carriage scan is reduced to 1/6, and six carriage scans are performed to record an image with the same resolution. The number of times to be played is also six. Furthermore, the recording mode is set to reduce the number of nozzles to be used to 1/3 and increase the thinning amount of pixels to be recorded in one carriage scan so that the number of pixels to be recorded in one carriage scan is 1/3. If switched, the number of pixels recorded in one carriage scan becomes 1/9, and nine carriage scans are performed to record an image of the same resolution. The number of times is 9 times.
For these reasons, it is possible to perform normal image recording while preventing ink curing failure with various patterns.

  The present invention is not limited to the above-described embodiment, and various improvements and design changes may be made without departing from the spirit of the present invention.

1 is a diagram illustrating a schematic configuration of an inkjet printer according to an embodiment of the present invention. It is a control block diagram which shows the main control structures of the inkjet printer in this Embodiment. It is a schematic diagram showing an example of a state of image recording in a normal recording mode in the ink jet printer of the present embodiment. FIG. 4A is a schematic diagram illustrating an example of a state of image recording in a recording mode at the time of first high humidity in the ink jet printer of the present embodiment, and FIG. 5B is a schematic diagram illustrating a state of a recorded image at that time. In the inkjet printer of this embodiment, (a) a schematic view showing another example of the state of image recording in the recording mode at the time of first high humidity, and (b) a schematic view showing the state of the recorded image at that time. . FIG. 4A is a schematic diagram illustrating an example of a state of image recording in a recording mode at the time of second high humidity in the ink jet printer according to the present embodiment, and FIG. 5B is a schematic diagram illustrating a state of a recorded image at that time. FIG. 4A is a schematic diagram illustrating an example of a state of image recording in a recording mode at the time of third high humidity in the inkjet printer of the present embodiment, and FIG. 5B is a schematic diagram illustrating a state of a recorded image at that time.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Inkjet printer 3 Recording medium conveyance mechanism 5,6,7,8 Recording head 5a Nozzle 5b Nozzle row 5c Nozzle surface 9,10 Ultraviolet irradiation apparatus 11 Carriage 13 Humidity detection apparatus 20 Control part 99 Recording medium A Conveyance direction B Scanning direction

Claims (7)

A recording medium transport mechanism for transporting the recording medium in a predetermined transport direction;
A scanning head having a nozzle for ejecting ink that is cured by irradiating ultraviolet rays onto the recording medium, and an ultraviolet irradiating device that irradiates ultraviolet rays to the ink that has landed on the recording medium are mounted, and scanning that is orthogonal to the transport direction. A carriage that can move in any direction,
An inkjet printer comprising:
A humidity detector that detects ambient humidity;
A control unit that switches a recording mode with a change in the amount of ultraviolet light irradiated to the ink from the ultraviolet irradiation device according to the humidity detected by the humidity detection device;
An ink jet printer comprising: The inkjet printer according to claim 1, wherein
The recording head has a plurality of nozzles;
The controller is
An inkjet printer characterized in that, as the recording mode switching, control is performed to switch the number of nozzles used when recording an image with the same resolution. The inkjet printer according to claim 2, wherein
The controller is
An ink jet printer that performs control to reduce the number of nozzles used when recording an image having the same resolution when the humidity detected by the humidity detection device is high. The inkjet printer according to claim 1, wherein
The controller is
An inkjet printer characterized in that, as the switching of the recording mode, control is performed to switch the thinning-out amount of pixels to be recorded by one nozzle in one scan when an image having the same resolution is recorded. The inkjet printer according to claim 4.
The controller is
When the humidity detected by the humidity detection device is high, control is performed to increase the thinning-out amount of pixels recorded by one nozzle in one scan when recording an image with the same resolution. Inkjet printer featuring. The inkjet printer according to claim 1, wherein
The recording head has a plurality of nozzles;
The controller is
An inkjet printer characterized in that, as the recording mode switching, control is performed to switch the number of nozzles used when recording an image of the same resolution and the thinning-out amount of pixels recorded by one nozzle in one scan. The inkjet printer according to claim 6.
The controller is
When the humidity detected by the humidity detector is high, the number of nozzles used when recording an image with the same resolution is reduced, and thinning out of pixels recorded by one nozzle in one scan is performed. An inkjet printer characterized by performing control to increase the amount.

Images