JP2003136692A - Ink jet printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink jet printer in which high quality printing can be sustained and printing can be performed without causing any deterioration of a recording medium even if UV radiation intensity is increased. SOLUTION: The ink jet printer A comprises rollers 1a and 1b for carrying a sheet-like recording medium R, a recording head 21 performing printing on the print face of the recording medium R being carried by the carrying rollers 1a and 1b by ejecting UV ink, and a member 4 for guiding the recording medium R being printed by means of the recording head 21 in the carrying direction D while supporting from the nonprint face side opposite to the print face. The ink jet printer A further comprises a temperature control mechanism for controlling the temperature of the recording medium R being printed by means of the recording head 21 to a target set temperature.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inkjet printer.

[0002]

2. Description of the Related Art Today, it is common practice to form an image on a monitor by a computer or the like and print the formed image on a recording medium such as a sheet of paper by an ink jet printer. The method of printing on a recording medium using an inkjet printer includes ultraviolet rays (hereinafter, UV
(Hereinafter referred to as “)” is used to cure the UV ink. The UV ink has a high viscosity at room temperature and a low viscosity when heated.
In this method, UV ink that has become low in viscosity by heating is attached to a recording medium, and then the recording medium to which the UV ink is attached is irradiated with UV to cure the UV ink and perform printing.

By the way, when the environmental temperature of the ink jet printer, especially the temperature inside the printer, changes due to the installation place, time, etc., the temperature of the recording medium to be printed also changes accordingly. Here, the viscosity of the UV ink changes depending on the temperature, and when the temperature of the recording medium changes, the adhesiveness and bleeding property of the UV ink on the recording medium also change due to the temperature change. That is, on the recording medium whose temperature has changed, the droplet diameter of the ejected UV ink slightly changes depending on the temperature of the recording medium and is not always constant. Therefore, the recording medium having the UV ink adhered thereto is directly irradiated with UV to fix the adhered UV ink on the recording medium. However, since the temperature of the recording medium at the time of printing is affected and the droplet diameter of the UV ink is unstable, There is a problem that the print quality of the final printed matter is not always the best.

Further, when the recording medium is irradiated with UV, the temperature of the recording medium rises. However, if the temperature of the recording medium is not suppressed, the recording medium itself may be deteriorated. However, there is a possibility that the print quality may be deteriorated. Therefore, it is difficult to further increase the UV irradiation intensity in order to prevent deterioration of the recording medium due to high temperature, and the UV irradiation intensity is necessarily limited.

[0005]

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide an ink jet printer capable of holding high quality printing and printing without changing the quality of a recording medium even when the UV irradiation intensity is increased. And

[0006]

The invention according to claim 1 is
A conveying unit that conveys a sheet-shaped recording medium; a head that ejects heated ink onto a printing surface of the recording medium that is conveyed by the conveying unit to perform printing; and a recording medium that performs printing by the head. An ink jet printer having a guide member for supporting the recording medium from the non-printing surface side opposite to the printing surface and guiding the recording medium in the conveying direction, wherein the temperature of the recording medium on which printing is performed by the head is a target setting. It is characterized by being controlled by temperature.

The "ink" here basically has a high viscosity at room temperature and a low viscosity when heated. Specifically, this “ink” is preferably a liquid having a viscosity at 30 ° C. of 50 to 3000 mPa · s. It is more preferably 50 to 1000 mPa · s, and even more preferably 100 to 500 mPa · s. At 50 mPa · s or less, bleeding is likely to occur, and clear printing cannot be performed. At 3000 mPa · s or higher, the smoothness of the image quality is lost. Furthermore, the viscosity at 60 ° C is 3 to
It is preferably a liquid of 30 mPa · s. 3 mPa
・ If it is less than s, problems may occur in high-speed discharge,
If it exceeds 30 mPa · s, the ejection property may be deteriorated. Further, particularly when ejected from a head composed of a piezo element, a liquid having a viscosity of 3 to 30 mPa · s is preferable. Also, "Control to the target set temperature"
The term "includes the meaning that the temperature of the recording medium is exactly equal to the set temperature, and means that the temperature is set to a certain range so that high-quality printing can be ensured.

According to the first aspect of the invention, the heated ink is ejected onto the recording medium to be printed for printing, but since the ink is heated and has a low viscosity, the recording medium is When it adheres to the recording medium, the time from the low-viscosity state to the high-viscosity state changes depending on the temperature of the recording medium. This inevitably changes the adhesiveness and bleeding property of the ejected ink on the recording medium.
Therefore, as shown in the above configuration, if the temperature of the recording medium on which printing is performed by the head is controlled to the target set temperature, the recording medium is always printed at the target set temperature. Therefore, in this case, the droplet size of the ink on the recording medium is always stable, that is, the adhesion and bleeding property of the ink on the recording medium are always stable. As a result, even if the temperature of the recording medium before printing changes due to the influence of the environment, it is possible to maintain high-quality printing in which the print quality does not deteriorate due to the temperature change of the recording medium.

Further, when UV is applied to a recording medium to which ink is attached, the temperature of this recording medium rises as shown in the prior art, but the temperature of the recording medium is set to a target as in the above configuration. By controlling the temperature, it is possible to suppress the temperature rise of the recording medium before and / or after the UV irradiation, and it is possible to prevent the recording medium from being deteriorated by the UV irradiation. Further, in this case, the UV irradiation intensity can be made stronger than in the conventional case, whereby the UV irradiation time can be shortened, and further, the shortening of the UV irradiation time can lead to the shortening of the printing process time.

According to a second aspect of the present invention, there is provided a transporting means for transporting the sheet-shaped recording medium, and a head for ejecting the heated ink onto the printing surface of the recording medium transported by the transporting means for printing. A recording medium on which printing is performed by the head is supported from the non-printing surface side opposite to the printing surface, and
An ink jet printer including a guide member for guiding a recording medium in a transport direction, comprising a temperature control mechanism for controlling a temperature of a recording medium on which printing is performed by the head to a target set temperature, the temperature control mechanism comprising: The feature is that the target set temperature can be changed.

In the ink jet printer according to the second aspect, the temperature control mechanism changes the temperature of the recording medium on which printing is performed by the head to a target set temperature, and the target set temperature is set to the environment of the printer and the recording medium itself. It can be changed based on the temperature, the properties that are different for each type of ink or recording medium used, and the like.
Therefore, according to the second aspect of the invention, by providing the temperature control mechanism, it is possible to obtain substantially the same effect as that of the first aspect.

Further, as in the ink jet printer according to the third aspect, the target set temperature may be switched according to the type of the recording medium on which the head prints. The "type of recording medium" means the form, material, thickness, heat capacity, and other properties of the recording medium itself.

According to a fourth aspect of the present invention, in the ink jet printer according to the second or third aspect, the temperature control mechanism includes temperature detection means for detecting the temperature of the recording medium,
The temperature control mechanism controls the temperature of the recording medium on which printing is performed by the head to the target set temperature, based on the temperature information of the recording medium detected by the temperature detecting unit.

According to the fourth aspect of the invention, the temperature detecting means is provided, and the temperature of the recording medium is controlled based on the temperature information of the recording medium detected by the temperature detecting means. The target set temperature can be surely controlled. As a result, high quality printing can be retained more reliably.

Further, as in the ink jet printer according to the fifth aspect, the ink may be a UV ink that cures when irradiated with ultraviolet rays.

An ink jet printer according to a sixth aspect may include a UV lamp for curing the UV ink. In this case, after printing is performed on the head, UV is irradiated from a UV lamp to cure the UV ink attached to the recording medium.

According to a seventh aspect of the present invention, there is provided an ink jet printer according to any one of the second to sixth aspects,
The temperature control mechanism includes a temperature adjusting unit that performs at least one of heating and cooling of the recording medium, the temperature adjusting unit being provided on the non-printing surface side of the recording medium, and the non-printing surface of the recording medium. At least one of heating and cooling of the recording medium is performed from the side. In the above configuration, the "temperature adjusting means" is provided on the non-printing surface side of the recording medium opposite to the printing surface, but the "temperature adjusting means" is of a contact type that directly contacts the non-printing surface of the recording medium. It may be a non-contact type which does not directly contact the non-printing surface of the recording medium. In addition, "temperature control means"
Is at least one of heating and cooling so as to cover a predetermined print area (area where ink is ejected) of the recording medium or an area wider than the print area,
It is preferable that the recording medium can be heated or cooled so that there is no uneven temperature distribution in the print area of the recording medium.

According to the invention of claim 7, the non-printing surface side of the recording medium opposite to the printing surface is directly heated and / or cooled. That is, the print surface side is not directly heated and / or cooled, but the non-print surface side is heated and / or cooled, whereby the temperature of the recording medium is controlled to the target set temperature. In such a configuration,
Since the print surface side of the recording medium is not directly affected by heating and / or cooling by the temperature adjusting means, the surface of the print surface is not altered and the print quality is not affected. As a result, deterioration of print quality can be prevented, and high-quality printing can be maintained.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of an ink jet printer of the present invention will be described below with reference to the drawings. In the present embodiment, an example in which the inkjet printer of the present invention is applied to an ultraviolet ray (hereinafter referred to as UV) inkjet printer will be described, but the present invention can be applied to various inkjet printers.

FIG. 1 is a cross-sectional view of an essential part of an ink jet printer for easily explaining the printing process on a recording medium which is a sheet of paper. As shown in the figure, the inkjet printer A schematically includes conveyance rollers 1a and 1b that have a role of conveying a recording medium R such as a sheet of paper.
A printing unit 2 for printing on the recording medium R conveyed by the conveying rollers 1a, 1b; a UV lamp 3 for irradiating the recording medium R on which ink is adhered with UV in the printing unit 2; and a recording medium R. And a guide member 4 for guiding in the transport direction D. A transport path is established along the transport direction D such that the recording medium R transported by the transport roller 1a passes through the printing unit 2 and is further transported by the transport roller 1b. In the present embodiment, an example is shown in which the paper feed source is roll paper wound in a roll shape, and this roll paper is referred to as “recording medium R”. Further, the recording medium R is not limited to the roll paper, but may be, for example, a cut sheet, and the type of paper can be changed appropriately. Further, the recording medium R may be made of a material other than paper, for example, a resin film. The recording medium R is not limited to the sheet shape, and may be a plate shape.

As shown in FIG. 1, the transport rollers 1a and 1b are provided.
Are spaced apart from each other at positions before and after printing is performed on the recording medium R in the printing unit 2. Conveyor rollers 1a, 1
b has a function as a transporting unit that drives the recording medium R in the transporting direction D by rotating in the same direction.

The printing unit 2 has an ink jet type recording head 21 and a carriage 2 having the recording head 21.
2 and a carriage rail 23 for guiding the movement of the carriage 22.

Ink such as cyan (C), magenta (M), yellow (Y), and black (B) is supplied to the recording head 21 by a tube or an ink cartridge (not shown). This ink has a high viscosity at room temperature, a low viscosity when heated, and a property of being cured when irradiated with UV. Below, this ink is called "UV
"Ink".

The carriage 22 has a recording head 21,
It is connected to the carriage rail 23 via the connecting portion 22a. The carriage rail 23 is a rail that extends substantially orthogonal to the transport direction D of the recording medium R, and is in the transport direction D.
The carriage 22 is guided in a direction substantially orthogonal to (a direction from the front side to the back side or the direction from the back side to the front side in FIG. 1). The direction in which the carriage rail 23 extends is referred to as a "scanning direction", and the following description will be given. When printing is performed on the recording medium R, UV ink is ejected from the recording head 21 to the recording medium R while the carriage 22 is guided by the carriage rail 23 and moves in the scanning direction.

The UV lamp 3 irradiates UV onto the printing surface of the recording medium R to which the UV ink is attached after the step of the printing section 2. By irradiating with UV, the UV ink attached to the recording medium R is set. The UV lamp 3 is fixed to the carriage rail 23 described above via the connecting portion 3a.

The guide member 4 is a plate-shaped member having a width equal to or larger than the width of the recording medium R. The guide member 4 is arranged so as to face the recording head 21, supports the recording medium R on which printing is performed by the recording head 21 from the non-printing surface side, and guides the recording medium R in the transport direction D. Is. The "non-printing surface" is the surface opposite to the printing surface of the recording medium R, that is, the surface on which printing is not performed. In detail, a portion of the guide member 4 arranged to face the recording head 21 is a platen 4a. A suction chamber (not shown) is provided on the back side of the platen 4a, and a suction port (not shown) formed of a plurality of small holes communicating with the suction chamber is provided. Platen 4a
Holds the non-printing surface of the recording medium R by suction.

By combining the above-mentioned respective components, the carriage 22 moves in the scanning direction with the recording medium R conveyed by the conveying rollers 1a, 1b being supported by the guide member 24 from the non-printing surface side. However, UV ink is ejected from the recording head 21 onto the printing surface of the recording medium R, and printing is performed.

Here, the structure of the characteristic portion of the present invention will be described. The inkjet printer A is equipped with the temperature control mechanism 5 shown in FIG. The temperature control mechanism 5 controls the temperature of the recording medium R on which printing is performed by the recording head 21 to a target set temperature. As shown in FIG. 2, the temperature control mechanism 5 is roughly provided with a temperature adjusting unit 51, a temperature detecting unit 52, an input unit 53, a control unit 54, and an interface 55. The temperature adjusting means 51, the temperature detecting means 52 or the input means 53, and the control unit 5
4 are connected to each other via an interface 55.

The temperature adjusting means 51 is provided in the vicinity of at least a part of the conveying path of the recording medium R conveyed by the conveying rollers 1a and 1b as the conveying means, and performs at least one of heating and cooling of the recording medium R. It is a thing. Specifically, as shown in FIG. 1, the temperature adjusting means 51 is arranged on the printing surface side of the recording medium R before printing by the recording head 21, and the heater 51 a and the reflector 5 are provided.
1b and.

The heater 51a has a function as a heat source extending in the width direction of the recording medium R (from the front side to the back side or from the back side to the front side in the plane of FIG. 1).
The reflector 51b is arranged so as to cover the heater 51a in a state where the printing surface side of the recording medium R is open, and the heater 51a
The radiant heat from the heater 51a generated by activating the is reflected. Therefore, these heaters 51a
Also, the reflector 51b has a function as a temperature adjusting means 51 for heating the recording medium R from the printing surface side.

The temperature detecting means 52 is arranged in the vicinity of at least a part of the conveying path of the recording medium R conveyed by the conveying rollers 1a and 1b in FIG. 1, and detects the temperature of the recording medium R. Specifically, the temperature detecting means 52
Is disposed on the printing surface side of the recording medium R before printing is performed by the recording head 21, and corresponds to the temperature sensor 52a shown in FIG. As shown in FIG. 1, the temperature sensor 52a is a non-contact type sensor that is fixed to the above-mentioned reflector 51b and does not directly contact the surface of the recording medium R. The temperature of the recording medium R is detected by the temperature sensor 52a. And
The temperature sensor 52a as the temperature detecting means 52 inputs the detected temperature information of the recording medium R (hereinafter referred to as "detected temperature information") to the control unit 54, as shown in FIG.

The input means 53 is an operation panel, a keyboard, etc., and inputs information (hereinafter referred to as “setting information”) regarding the type (form, material, thickness, etc.) of the recording medium R to the control section 54. is there. When the setting information is input to the operation panel, the keyboard or the like by the manual operation of the operator, the input unit 53 inputs the input setting information to the control unit 54. It should be noted that specifically, the setting information is information regarding properties of the recording medium R such as form: roll paper, material: paper, thickness: 0.01 mm.

The control section 54 includes a memory 54a and a CPU 5
4b and. The memory 54a has a temperature detecting means 5
The detected temperature information output from 2 and the setting information output from the input means are stored. Further, the memory 54a stores, as a data table, target set temperature information corresponding to the set information (hereinafter referred to as "target temperature information"). Therefore, in the memory 54a, the target temperature information can be switched according to the setting information by the input means 53. Specifically, when the setting information such as form: roll paper, material: paper, thickness: 0.01 mm is changed to setting information such as form: film, material: resin, thickness: 0.05 mm, the target temperature is changed. Also, the target temperature information can be switched so as to switch from 28 ° C to 26 ° C. The CPU 54b reads out the detected temperature information and the target temperature information stored in the memory 54a, and performs various calculations such as comparing the information. And the CPU 54
When it is determined that the temperature of the recording medium R needs to be raised or lowered in accordance with the calculation result, b sends an operation signal for causing the temperature adjusting means 51 to perform at least one of heating and cooling. Further, the CPU 54b causes the recording medium R to follow the calculation result.
If it is determined that the temperature increase or decrease of the temperature is unnecessary, the operation signal is not sent to the temperature adjusting means 51.

The interface 55 mediates transfer of various information and signals performed between the temperature adjusting means 51, the temperature detecting means 52 or the input means 53 and the control section 54.

Next, in the ink jet printer A according to the present invention, the operation from the feeding of the recording medium R to the ejection of the recording medium R will be described. First, the setting information is input to the input means 53 such as the operation panel and the keyboard by the manual operation of the operator. In this case, the setting information is information on the properties of the recording medium R such as form: roll paper, material: paper, thickness: 0.01 mm. As a result, the input unit 53 inputs the setting information to the control unit 54 via the interface 55. This setting information is stored in the memory 54a of the control unit 54. In the inkjet printer A, the leading end of the recording medium R set on a spindle (not shown) is guided to the conveying roller 1a along a paper feed guide (not shown), and the leading end of the recording medium R is aligned.

The aligned recording medium R is conveyed to the printing unit 2 by the conveying rollers 1a. During this time, the temperature sensor 52a as the temperature detecting means 52 is operated by the recording head 21.
Detects the temperature of the recording medium R on which printing is to be performed. The temperature sensor 52a inputs the detected temperature information to the control unit 54 via the interface 55. This detected temperature information is stored in the memory 54a of the control unit 54. Then, the CPU 54a of the control unit 54 reads out the detected temperature information stored in the memory 54a and the target temperature information corresponding to the setting information, and performs a comparison calculation. And the CPU 54b
When it is determined that the temperature of the recording medium R needs to be raised or lowered according to the calculation result, the operation signal is input to the temperature adjusting means 51 via the interface 55.
Then, the temperature adjusting means 51 operates. In this case, the heater 51a operates to generate radiant heat from the heater 51a,
The recording medium R is heated from the printing surface side. When it is determined that the temperature of the recording medium R does not need to be raised or lowered according to the calculation result, the CPU 54b does not input the operation signal to the temperature adjusting means 51. Therefore, the temperature adjusting means 5
The heater 51a as 1 does not operate, and the recording medium R is not heated. In this way, the temperature control mechanism 5 controls the temperature of the recording medium R on which printing is performed by the recording head 21 to the target set temperature based on the temperature information detected by the temperature detecting means 52.

Subsequently, while the temperature is controlled by the temperature control mechanism 5, the recording medium R is supported by the guide member 4 on the non-printing surface side and is guided in the transport direction D. The recording medium R is supported on the non-printing surface side by the guide member 4, but is in a state of being suction-held by the platen 4a as described above.

Then, the recording head 21 prints on the printing surface of the recording medium R on which the non-printing surface is supported. Specifically, in a state where the non-printing surface of the recording medium R is suction-held by the platen 4a, the recording head 21 moves in the scanning direction along with the operation of the carriage 22 and ejects UV ink onto the printing surface of the recording medium. , Printing is performed. The recording medium R after printing is performed by the recording head 2
It is transported to the downstream side of the transport direction D from 1, that is, immediately below the UV lamp 3.

Subsequently, the recording medium R conveyed immediately below the UV lamp 3, that is, the recording medium R to which the UV ink is attached is irradiated with UV from the UV lamp 3, and the UV ink attached to the recording medium R is cured. It will be. Then, the recording medium R which has undergone the above steps passes through a paper ejection guide (not shown) and is ejected.

As described above, according to the ink jet printer A according to the present embodiment, the temperature control mechanism 5 controls the temperature of the recording medium R on which the recording head 21 performs printing to the target set temperature, and the recording medium R is always kept. Printing is performed with the target set temperature maintained. In this case, since the temperature of the recording medium R is always kept constant, the time until the UV ink attached to the recording medium R changes from the low viscosity state to the high viscosity state is the temperature of the recording medium R. It will not change due to. Therefore, UV on the recording medium R
The droplet size of the ink is always stable, that is, the adhesion and bleeding properties of the UV ink on the recording medium R are always stable. As a result, the recording medium R before printing is affected by the environment.
Even if the temperature changes, the print quality does not deteriorate due to the temperature change of the recording medium R, and high quality printing can be maintained.

Further, in the ink jet printer A according to the present embodiment, the temperature of the recording medium R is controlled based on the detected temperature information of the recording medium R detected by the temperature detecting means 52, so that the temperature of the recording medium R is controlled. Can be reliably controlled by the target set temperature, and thus high-quality printing can be retained more reliably.

Next, a modified example of the above temperature control mechanism 5 will be described with reference to FIGS. Note that, in detail, FIG.
In the modification shown in FIG. 5, at least one of the temperature adjusting means 51 and the temperature detecting means 52 shown in FIG. 2 is different,
The other components are the same as those in the above example. Therefore, the same reference numerals as those in the above example are attached to these constituent elements, and detailed description thereof will be omitted.

As shown in FIG. 3, a cooling system using a compressor is applied as the temperature adjusting means 51. This cooling system includes a compressor 51c and a cooling unit 5
1d, and the compressor 51c and the cooling unit 51d
And a hose 51e for piping. In this cooling system, the compressor 51c compresses and liquefies the refrigerant, and the cooling unit 51d vaporizes the liquefied refrigerant to cool the recording medium R. As the temperature detecting means 52, the temperature sensor 52a shown in FIG. 1 is fixed to the cooling unit 51d. Therefore, in this case, based on the temperature information detected by the temperature sensor 52a as the temperature detecting means 52, the cooling system using the compressor 51c is operated to cool the recording medium R to be printed by the recording head 21, The temperature of the recording medium R is controlled to the target set temperature.

Further, as shown in FIG. 4, the temperature adjusting means 5
A cooling system using a Peltier element is applied as 1. This cooling system is provided with Peltier element built-in rollers 51f and 51g having Peltier elements built-in. The Peltier element built-in rollers 51f and 51g are arranged adjacent to each other so that the recording medium R is interposed therebetween, and are driven to rotate in opposite directions to convey the recording medium R in the conveying direction D while sandwiching the recording medium R therebetween. These Peltier element built-in rollers 51f,
In 51g, when the built-in Peltier element is activated, the sandwiched recording medium R can be cooled from both the printing side and the non-printing side. Since the Peltier device absorbs heat and radiates heat at the same time, in this case, for example, these rollers 51f and 51g with a built-in Peltier device are made hollow, and air is blown by a fan or the like into the hollow portion,
It is necessary to radiate heat. Further, a thermocouple sensor 52b is applied as the temperature detecting means 52. The thermocouple sensor 52b is
The temperature of the recording medium R is detected from the thermoelectric quantity generated by the temperature difference between the two contacts by connecting two different kinds of metal in a ring shape. Therefore, in this case, based on the temperature information detected by the thermocouple sensor 52b as the temperature detecting means 52, the cooling system using this Peltier element is operated to cool the recording medium R on which printing is performed by the recording head 21, The temperature of the recording medium R is controlled to the target set temperature.

Further, as shown in FIG. 5, a heating system using a heater 51h and a radiant lamp 51i as the temperature adjusting means 51 is applied. The heater 51h is arranged on the back side of the guide member 4. When the heater 51h is activated, the recording medium R supported on the non-printing surface side by the guide member 4 (or the platen 4a) can be heated from the non-printing surface side via the guide member 4 (or the platen 4a). ing. The guide member 4 (or the platen 4
The material a) is preferably formed of a material having a high thermal conductivity, and is preferably formed of a material capable of quickly and efficiently mediating the heating of the recording medium R. The radiant lamp 51i is fixed to the carriage rail 23 of the printing unit 2 and radiates infrared rays. When the radiation lamp 51i is activated, infrared rays are radiated to the printing surface side of the recording medium R, and the recording medium R can be heated from the printing surface side. Further, as the temperature detecting means 52, a thermocouple sensor 52b similar to that shown in FIG. 4 is used.
Apply. Therefore, in this case, based on the temperature information detected by the thermocouple sensor 52b as the temperature detecting means 52, the heating system using the heater 51h and the radiation lamp 51i is operated, and the recording medium R on which recording is performed by the recording head 21 is performed. Is heated to control the temperature of the recording medium R to a target set temperature. In this case, the temperature of the recording medium R may be controlled by providing a heating system for only one of the heater 51h and the radiation lamp 51i.

As described above, also in the modified examples shown in FIGS. 3 to 5, the same effect as that of the above example shown in FIG. 1 is obtained. Further, in the example shown in FIGS. 1 and 3 to 5, since the temperature of the recording medium R is controlled to the target set temperature by the control mechanism 5, U
It is possible to prevent the temperature of the recording medium R from rising due to V irradiation, and prevent the recording medium R from being deteriorated. Further, in this case, the UV irradiation intensity can be made stronger than in the conventional case, whereby the UV irradiation time can be shortened, and further, the shortening of the UV irradiation time can lead to the shortening of the printing process time. Note that FIG. 1 and FIGS.
In the example shown in FIG. 5, the temperature adjusting means 51 is provided at a position on the upstream side of the recording head 21 in the transport direction D or at a position facing the recording head 21 to heat the recording medium R before printing or during printing. Although at least one of cooling is performed, the temperature adjusting means 51 is moved from the recording head 21 in the transport direction D.
The recording medium R after being printed by being provided at a position on the downstream side of the
May be heated or cooled.

In this embodiment, FIG. 1 except FIG. 2 is used.
~ Fig. 5 shows various temperature control means 51 and temperature detection means 5
2 shows the configuration in which the recording medium R is heated or cooled to control the temperature of the recording medium R. However, the temperature of the recording medium R may be controlled by combining these temperature adjusting means 51 and temperature detecting means 52 in various ways to perform both heating and cooling. Further, here, like the heater 51h shown in FIG.
1 is provided on the non-printing surface side of the recording medium R, and the recording medium R
It is preferable to perform at least one of heating and cooling of the recording medium R from the non-printing surface side. Because the printing surface side of the recording medium R is not directly affected by the heating and / or cooling by the temperature adjusting means 51, the surface of the printing surface is not altered and the printing quality is not affected. This is because deterioration of print quality can be prevented and high quality printing can be maintained. In addition, the heater 5 shown in FIG.
When the temperature adjusting means 51 is provided on the back side of the guide member 4 (or the platen 4a) as in 1h, it is preferable that the guide member 4 (or the platen 4a) is made of a material having a high thermal conductivity. It is preferable that the recording medium R is formed of a material that can mediate heating or cooling quickly and efficiently.

[0048]

According to the present invention, since the temperature of the recording medium is controlled to the target set temperature, the recording medium is always printed at the target set temperature. Therefore, in this case, the droplet size of the ink on the recording medium is always stable, that is, the adhesion and bleeding property of the ink on the recording medium are always stable. As a result, even if the temperature of the recording medium before printing changes due to the influence of the environment, it is possible to maintain high-quality printing in which the print quality does not deteriorate due to the temperature change of the recording medium.

Further, in the present invention, since the temperature of the recording medium is controlled to the target set temperature, it is possible to prevent the temperature of the recording medium from becoming high due to UV irradiation, and prevent the recording medium from deteriorating. can do. Further, in this case, the UV irradiation intensity can be made stronger than in the conventional case, whereby the UV irradiation time can be shortened, and further, the shortening of the UV irradiation time can lead to the shortening of the printing process time.

[Brief description of drawings]

FIG. 1 is a main-portion cross-sectional view showing a printing portion of an inkjet printer according to an embodiment.

FIG. 2 is a block diagram showing a temperature control mechanism provided in the inkjet printer.

FIG. 3 is a cross-sectional view of an essential part showing a modified example of the printed portion.

FIG. 4 is a main-portion cross-sectional view showing a modified example of the printed portion.

FIG. 5 is a cross-sectional view of an essential part showing a modified example of the printed portion.

[Explanation of symbols]

A inkjet printer D conveying direction R recording medium 1a, 1b conveying roller (conveying means) 3 UV lamp 4 guide member 5 temperature control mechanism 21 recording head (head) 51 temperature adjusting means 51a heater (a part of temperature adjusting means) 51b reflector (Part of temperature adjusting means) 51c Compressor (part of temperature adjusting means) 51d Cooling part (part of temperature adjusting means) 51e Hose (part of temperature adjusting means) 51f, 51g Peltier element built-in roller (temperature adjusting means) 51h Heater (part of temperature adjusting means) 51i Radiant lamp (part of temperature adjusting means) 52 Temperature detecting means 52a Temperature sensor 52b Thermocouple sensor

Claims (7)

[Claims] 1. A conveyance means for conveying a sheet-shaped recording medium, a head for ejecting heated ink onto a printing surface of the recording medium conveyed by the conveyance means to perform printing, and printing by the head. An ink jet printer comprising: a recording medium which is supported from a non-printing surface side opposite to a printing surface, and a guide member which guides the recording medium in a conveyance direction, wherein the recording medium is printed by the head. An inkjet printer characterized in that the temperature is controlled to a target set temperature. 2. A conveyance means for conveying a sheet-shaped recording medium, a head for ejecting heated ink onto a printing surface of the recording medium conveyed by the conveyance means to perform printing, and printing by the head. An ink jet printer comprising: a recording medium which is supported from a non-printing surface side opposite to a printing surface, and a guide member which guides the recording medium in a conveyance direction, wherein the recording medium is printed by the head. An inkjet printer, comprising: a temperature control mechanism for controlling a temperature to a target set temperature, wherein the temperature control mechanism is capable of changing the target set temperature. 3. The ink jet printer according to claim 2, wherein the target set temperature is switched according to the type of a recording medium on which printing is performed by the head. 4. The ink jet printer according to claim 2 or 3, wherein the temperature control mechanism includes temperature detection means for detecting the temperature of the recording medium, and the temperature control mechanism detects the recording detected by the temperature detection means. An ink jet printer, wherein the temperature of a recording medium on which printing is performed by the head is controlled to the target set temperature based on medium temperature information. 5. The inkjet printer according to any one of claims 1 to 4, wherein the ink is a UV ink that cures when irradiated with ultraviolet rays. 6. The inkjet printer according to claim 5, further comprising a UV lamp for curing the UV ink. 7. The ink jet printer according to any one of claims 2 to 6, wherein the temperature control mechanism includes temperature adjusting means for performing at least one of heating and cooling of the recording medium, and the temperature adjusting means. An ink jet printer provided on the non-printing surface side of a recording medium, wherein at least one of heating and cooling of the recording medium is performed from the non-printing surface side of the recording medium.