JP2005254806A - Ink-jet recording device and ink-jet recording method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ink-jet recording device which can prevent an excessive glossiness of a transparent or an opaque resin packaging material due to roughness or asperities of an image, occurring during image recording on the packaging material, and to provide an ink-jet recording method. <P>SOLUTION: The ink-jet recording device is formed of a plurality of recording heads 6, 6, etc. consisting of white ink recording heads 9, 10 for ejecting a white ink, a process color ink recording heads 11, 12, 13, 14, 15, 16, 19, 20 for ejecting inks of process colors, respectively, and transparent ink recording heads 17, 18 for ejecting a transparent ink. After the white ink is ejected from the white ink recording head 9, the process color inks are ejected from at least one of the process color ink recording heads 11, 12, 13, 14, 15, 16, 19, 20, and thereafter the transparent ink is ejected from the transparent ink recording head 18. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an ink jet recording apparatus and an ink jet recording method, and more particularly to an ink jet recording apparatus and an ink jet recording method using a transparent ink.

  When a color image is recorded on a resin packaging material or the like, image recording is mainly performed by gravure printing in which ink is put in a concave portion formed on a printing plate and directly transferred to a recording medium. The feature of gravure printing is that it can express characters, symbols, pictures, etc. in a rich color and can be recorded on a large amount of recording media at high speed. Here, for example, when recording on a transparent packaging material, it may be recorded on the back side of the packaging material in order to maintain durability against scratching of the recording surface, which is called “back printing”. Further, when recording on an opaque packaging material, the recording is performed on the front side of the packaging material, which is called “surface printing”.

  Gravure printing is a useful recording technique with the above-mentioned features when recording characters, symbols, pictures, etc. with a special color such as white on these packaging materials, but actually records images. It is necessary to produce a plate in the previous process, and costs and time are consumed for producing this plate.

  Therefore, paying attention to the recording technology using the inkjet recording device that does not require a pre-process, characters, symbols, pictures, etc., with a process color with a special color such as white as the background color for transparent or opaque resin packaging materials As an ink jet recording apparatus capable of recording the image, an ink jet recording apparatus having a control means capable of selectively performing front printing and back printing has been developed (for example, see Patent Document 1).

  In addition, as an ink jet recording apparatus that can handle various recording media, an ink jet recording apparatus using a photocurable ink is known, and the ink is instantaneously cured by irradiating the ink landed on the recording medium with light. Therefore, there is little ink permeation or bleeding into the recording medium, and it is possible to record images not only on plain paper but also on recording media such as plastic and metal that do not have an image receiving layer and have no ink absorbability. .

  However, in general, when image recording is performed using a recording medium having an image receiving layer, most of the ink is absorbed by the recording medium, whereas the recording medium does not have an image receiving layer using photocurable ink. When the image is recorded using the ink, the ink is cured and fixed at the same time as the light is irradiated and is not absorbed by the recording medium. Therefore, the ink remains on the surface of the recording medium and the ink landing portion is raised. Harden.

  In this way, when there is a cured film with a difference in smoothness on the surface of the recording medium, that is, in the image, it is recognized as a variation in glossiness visually, and the image quality as a whole image is deteriorated, resulting in high-definition image recording. There was a problem that could not be done.

Therefore, in order to alleviate the difference in glossiness between the image portion and the non-image portion, the composition of the transparent ink that is not colored or substantially uncolored is appropriately adjusted, and this transparent ink is applied to the non-image portion on the recording medium. An ink jet recording apparatus has been developed that smoothes the surface of a recording medium by discharging the ink (see, for example, Patent Document 2).
JP 2003-285427 A JP 2003-191601 A

  However, when an ink jet recording apparatus using ultraviolet curable ink is used to perform surface printing that discharges a process color after discharging a special color such as white as a background color on a transparent or opaque resin packaging material Since the image is cured and fixed at the same time as it is irradiated with light and is not absorbed by the recording medium, the texture becomes uneven or uneven, resulting in excessive glossiness. As compared with the case of reverse printing that discharges, there is a problem that the printing and printing quality deteriorates.

  In addition, on a transparent or opaque resin packaging material, it is possible to record characters, symbols, pictures, etc. with process colors using a special color such as white as a background color, and a recording medium having no image receiving layer. On the other hand, an inkjet recording apparatus and an inkjet recording method that can make glossiness uniform with transparent ink have not been developed.

  The present invention has been made in view of the above points, and an ink jet recording apparatus that prevents excessive glossiness due to roughness or unevenness of an image generated when an image is recorded on a packaging material made of a transparent or opaque resin. It is another object of the present invention to provide an ink jet recording method.

In order to solve the above problems, an ink jet recording apparatus according to the invention described in claim 1 is an ink jet recording apparatus including a plurality of recording heads that eject ink onto a recording medium,
The plurality of recording heads include a background color ink recording head that discharges background color ink, a process color ink recording head that discharges each process color ink, and a transparent ink recording head that discharges transparent ink. And consists of
The recording head for transparent ink is disposed on the most downstream side in the conveyance direction of the recording medium,
The background color ink recording head is arranged upstream of the transparent ink recording head in the transport direction of the recording medium.

According to the first aspect of the present invention, after ink is ejected from the background color ink recording head, ink is ejected from at least one process color ink recording head among the process color ink recording heads, and then transparent. Since ink is ejected from the ink recording head, light transmission can be prevented by the background color ink ejected first.
In addition, the amount of ink on the recording medium can be made uniform by the transparent ink that is finally ejected, and unevenness on the surface of the recording medium can be prevented.

An ink jet recording apparatus according to a second aspect of the present invention includes a carriage that scans in a direction orthogonal to a conveyance direction of the recording medium,
The background color ink recording head, the process color ink recording head, and the transparent ink recording head are mounted on the carriage.

  According to the second aspect of the present invention, the background color ink recording head, each process color ink recording head, and the transparent ink recording head are mounted on a single carriage. With this simple configuration, it is possible to prevent light from being transmitted by the background color ink and to prevent the surface of the recording medium from being uneven by the transparent ink.

  According to a third aspect of the present invention, there is provided the inkjet recording apparatus according to the third aspect, wherein the background color ink recording heads are arranged at one or both ends on the most upstream side of the recording heads arranged in a line along the scanning direction. The ink recording heads are arranged at the other end or both ends on the most downstream side of the recording heads arranged in a line along the scanning direction.

  According to the third aspect of the present invention, the background color ink recording heads are arranged at one or both ends on the most upstream side of the recording heads arranged in a line along the scanning direction. Since the recording heads arranged at the most downstream side or both ends of the recording heads arranged in a line along the scanning direction are arranged in a single line along the scanning direction, the background color ink recording head and the transparent ink recording head are arranged. Without disposing, by arranging the recording head for each process color ink at one end or both ends, and the other end or both ends, it is possible to prevent the occurrence of unevenness on the surface of the recording medium along with the transmission of light. it can.

  According to a fourth aspect of the present invention, in the ink jet recording apparatus, the background color ink recording head, the process color ink recording head, and the transparent ink recording head are formed into a substantially rectangular parallelepiped shape. The line head is arranged such that the longitudinal side of the recording medium is orthogonal to the conveyance direction of the recording medium.

  According to the invention described in claim 4, the recording head for background color ink, the recording head for each process color ink, and the recording head for transparent ink are formed in a substantially rectangular parallelepiped shape, and the longitudinal side of each recording head is the recording medium. Since the line head is arranged so as to be orthogonal to the transport direction, light transmission can be prevented by the background color ink and the transparent ink can be prevented by a simple configuration considering the arrangement of each line head. Unevenness can be prevented from occurring on the surface of the recording medium.

According to a fifth aspect of the present invention, there is provided the ink jet recording apparatus, wherein the ink to be ejected from each recording head of the background color ink recording head, the process color ink recording head, and the transparent ink recording head is an ink droplet. Discharged,
The amount of ink droplets ejected from at least one of the background color ink recording head and the transparent ink recording head is equal to the amount of ink droplets ejected from the process color ink recording head. It is characterized by being larger than the discharge amount per droplet.

  According to the fifth aspect of the present invention, the amount of ink droplets ejected from the background color ink recording head and the transparent ink recording head is the ink ejected from each process color ink recording head. Since there is more discharge amount per droplet, when only one ink droplet is ejected from each recording head onto the recording medium, the ink droplets from the recording head for background color ink and the recording head for transparent ink are recorded on the recording medium. The occupation area occupied by each process color ink is larger than the occupation area of the ink droplets from each process color ink recording head, so that the number of background color ink recording heads and the transparent ink recording heads can be reduced or reduced in size. Can do.

  An ink jet recording apparatus according to a sixth aspect of the invention is characterized in that the background color ink, the process color ink, and the transparent ink are ultraviolet curable inks.

  According to the sixth aspect of the present invention, since the background color ink, the process color ink, and the transparent ink are ultraviolet curable inks, the sensitivity to ultraviolet rays is high, and the amount of ultraviolet irradiation is small. Even in such a case, the landed ink droplets can be easily cured on the recording medium.

  An ink jet recording apparatus according to a seventh aspect of the invention is characterized in that the carriage includes an ultraviolet irradiation device for irradiating each ink droplet landed on the recording medium with ultraviolet rays.

  According to the invention described in claim 7, since the carriage includes the ultraviolet irradiation device that irradiates each ink droplet landed on the recording medium with ultraviolet rays, the ultraviolet irradiation device emits short wavelength ultraviolet rays having a large light energy. By irradiating, each ink droplet landed on the recording medium can be efficiently cured.

  According to an eighth aspect of the present invention, there is provided an ink jet recording apparatus in which a recording medium on which an image is recorded by the background color ink, the process color ink, and the transparent ink is a transparent or translucent resin film. It is characterized by being.

  According to the invention described in claim 8, since the recording medium on which the image is recorded is a transparent or translucent resin film, the ink having a high viscosity is used to prevent the ink from flowing on the recording medium. Even in such a case, the amount of ink on the recording medium is made uniform by the discharged transparent ink, and unevenness on the surface of the recording medium can be prevented.

The ink jet recording method according to the invention of claim 9 is:
A recording medium transporting process for transporting the recording medium to a recording area where ink is ejected;
For each pixel on the recording surface of the conveyed recording medium, the background color ink is first ejected from the background color ink recording head and finally the transparent ink is ejected from the transparent ink recording head. And an ink discharge step of forming a lowermost layer made of the background color ink and an uppermost layer made of the transparent ink on the surface.

  According to the ninth aspect of the invention, the background color ink is first ejected from the background color ink recording head to each pixel on the recording surface of the recording medium conveyed in the recording medium conveying step, and finally, A transparent ink is ejected from the transparent ink recording head, thereby forming an ink ejection step for forming a lowermost layer made of background color ink and an uppermost layer made of transparent ink on the recording surface. The lower layer can prevent light from being transmitted, and the uppermost layer made of transparent ink can uniformize the amount of ink on the recording medium, thereby preventing the surface of the recording medium from being uneven.

  In the ink jet recording method according to the tenth aspect, at least one of the process color inks is ejected in the ink ejecting step, and the background color is formed on a pixel from which the process color ink is ejected. The process color ink is ejected after the ink is ejected and before the transparent ink is ejected.

  According to the invention described in claim 10, in the ink ejection step, at least one of the process color inks is ejected, and after the background color ink is ejected on the pixels from which the process color ink is ejected. Since the process color ink is ejected before the transparent ink is ejected, the process color ink prevents the background color ink and the transparent ink from interfering with each other and prevents the transmission of light. It is possible to prevent the occurrence of unevenness.

  According to an eleventh aspect of the present invention, there is provided an ink jet recording method in which an ejection amount per one droplet of ink droplets ejected from at least one of the background color ink recording head and the transparent ink recording head is the process. It is characterized by being larger than the ejection amount per ink droplet ejected from the color ink recording head.

  According to the eleventh aspect of the present invention, the discharge amount per ink droplet ejected from at least one of the background color ink recording head and the transparent ink recording head is from the process color ink recording head. Since it is larger than the ejection amount per ejected ink droplet, when only one ink droplet is ejected from each recording head onto the recording medium, the ink droplets from the background color ink recording head and the transparent ink recording head The occupied area on the recording medium is larger than the occupied area of the ink droplets from each process color ink recording head, so that the number of installed background color ink recording heads and the transparent ink recording head can be reduced or reduced in size. Can be achieved.

  In an ink jet recording method according to a twelfth aspect of the present invention, an ultraviolet curable ink is used for the background color ink, the process color ink, and the transparent ink. It is characterized by comprising an ultraviolet irradiation step of irradiating each ink droplet landed on the recording medium with ultraviolet rays.

  According to the twelfth aspect of the present invention, ultraviolet curable ink is used for the background color ink, each process color ink, and the transparent ink, and each ink landed on the recording medium after the ink ejection step. Since it has an ultraviolet irradiation process to irradiate the droplets with ultraviolet rays, each ink droplet that has landed on the recording medium is made efficient by irradiating ultraviolet curable ink with high sensitivity to ultraviolet rays with short wavelength ultraviolet rays with high light energy. Can be cured well.

According to the first aspect of the present invention, after ink is ejected from the background color ink recording head, ink is ejected from at least one process color ink recording head among the process color ink recording heads, and then transparent. Since the ink is ejected from the ink recording head, it is possible to prevent light from being transmitted by the background color ink that is ejected first, thereby making the image clearly stand out and being transparent or translucent. An image can be recorded on a recording medium.
In addition, the amount of ink on the recording medium is made uniform by the transparent ink that is finally ejected, and it is possible to prevent the surface of the recording medium from becoming uneven. It is possible to record a uniform high-definition image.

  According to the second aspect of the present invention, the background color ink recording head, each process color ink recording head, and the transparent ink recording head are mounted on a single carriage. With a simple configuration, it is possible to prevent light from being transmitted by the background color ink, and it is possible to prevent unevenness on the surface of the recording medium from being generated by the transparent ink. And cost reduction.

  According to the third aspect of the present invention, the background color ink recording heads are arranged at one or both ends on the most upstream side of the recording heads arranged in a line along the scanning direction. Since the recording heads arranged at the most downstream side or both ends of the recording heads arranged in a line along the scanning direction are arranged in a single line along the scanning direction, the background color ink recording head and the transparent ink recording head are arranged. Without disposing, by arranging the recording head for each process color ink at one end or both ends, and the other end or both ends, it is possible to prevent the occurrence of unevenness on the surface of the recording medium along with the transmission of light. it can.

  According to the invention described in claim 4, the recording head for background color ink, the recording head for each process color ink, and the recording head for transparent ink are formed in a substantially rectangular parallelepiped shape, and the longitudinal side of each recording head is the recording medium. Since the line head is arranged so as to be orthogonal to the transport direction, light transmission can be prevented by background color ink and recording can be performed by transparent ink by a simple configuration in which the arrangement of each line head is taken into consideration. It becomes possible to prevent unevenness on the surface of the medium, which makes it possible to reduce the size and cost of the apparatus.

  According to the fifth aspect of the present invention, the discharge amount of the ink droplets from the background color ink recording head and the transparent ink recording head is the amount of ink droplets discharged from each process color ink recording head. Since the discharge amount per droplet is larger, when only one ink droplet is discharged from each recording head onto the recording medium, the ink droplets from the background color ink recording head and the transparent ink recording head occupy on the recording medium. Since the occupation area is larger than the occupation area of ink droplets from each process color ink recording head, the number of background color ink recording heads and transparent ink recording heads can be reduced or reduced in size. Accordingly, it is possible to reduce the size of the ink jet recording apparatus and reduce the manufacturing cost.

  According to the sixth aspect of the present invention, since the background color ink, the process color ink, and the transparent ink are ultraviolet curable inks, the sensitivity to ultraviolet rays is high, and the amount of ultraviolet irradiation is small. Even if it is, it is possible to easily cure the landed ink droplets on the recording medium, thereby recording a high-definition image on a recording medium such as a resin film having poor ink absorption, regardless of the recording medium. can do.

  According to the invention described in claim 7, since the carriage includes the ultraviolet irradiation device that irradiates each ink droplet landed on the recording medium with ultraviolet rays, the ultraviolet irradiation device emits short wavelength ultraviolet rays having a large light energy. By irradiating, it is possible to efficiently cure each ink droplet that has landed on the recording medium. This makes it possible to efficiently use energy, reduce the size of the apparatus, and reduce manufacturing costs.

  According to the invention described in claim 8, since the recording medium on which the image is recorded is a transparent or translucent resin film, the ink having a high viscosity is used to prevent the ink from flowing on the recording medium. Even in such a case, the amount of ink on the recording medium is made uniform by the discharged transparent ink, and it is possible to prevent unevenness on the surface of the recording medium. A high-definition image with uniform gloss can be recorded without any processing.

According to the ninth aspect of the invention, the background color ink is first ejected from the background color ink recording head to each pixel on the recording surface of the recording medium conveyed in the recording medium conveying step, and finally, A transparent ink is ejected from the transparent ink recording head, thereby forming an ink ejection step for forming a lowermost layer made of background color ink and an uppermost layer made of transparent ink on the recording surface. Light transmission can be prevented by the lower layer, whereby an image can be clearly highlighted and an image can be recorded on a transparent or translucent recording medium.
In addition, the uppermost layer made of transparent ink makes the amount of ink on the recording medium uniform, and it is possible to prevent unevenness on the surface of the recording medium, thereby preventing glossiness without any special post-treatment. It is possible to record a uniform high-definition image.

  According to the invention described in claim 10, in the ink ejection step, at least one of the process color inks is ejected, and after the background color ink is ejected on the pixels from which the process color ink is ejected. Since the process color ink is ejected before the transparent ink is ejected, the process color ink prevents the background color ink and the transparent ink from interfering with each other and prevents the transmission of light. As a result, it is possible to prevent the occurrence of unevenness, and the same effects as those of the invention of claim 9 can be obtained.

  According to the eleventh aspect of the present invention, the discharge amount per ink droplet ejected from at least one of the background color ink recording head and the transparent ink recording head is from the process color ink recording head. Since it is larger than the ejection amount per ejected ink droplet, when only one ink droplet is ejected from each recording head onto the recording medium, the ink droplets from the background color ink recording head and the transparent ink recording head The occupied area on the recording medium is larger than the occupied area of the ink droplets from each process color ink recording head, so that the number of installed background color ink recording heads and the transparent ink recording head can be reduced or reduced in size. As a result, it is possible to reduce the size of the ink jet recording apparatus and the manufacturing cost.

  According to the twelfth aspect of the present invention, ultraviolet curable ink is used for the background color ink, each process color ink, and the transparent ink, and each ink landed on the recording medium after the ink ejection step. Since it has an ultraviolet irradiation process to irradiate the droplets with ultraviolet rays, each ink droplet that has landed on the recording medium is made efficient by irradiating ultraviolet curable ink with high sensitivity to ultraviolet rays with short wavelength ultraviolet rays with high light energy. Thus, it is possible to cure well, so that a high-definition image can be recorded on a recording medium having poor ink absorbability, such as a resin film, regardless of the recording medium.

  The best mode for carrying out the present invention will be described below with reference to the drawings. However, although various technically preferable limitations for implementing the present invention are given to the embodiments described below, the scope of the invention is not limited to the following embodiments and illustrated examples.

The ink jet recording apparatus and the ink jet recording method according to the present invention will be described with reference to FIGS.
As shown in FIG. 1, the inkjet recording apparatus 1 according to the present invention is configured such that each constituent member is covered with a casing (not shown), and a planar shape that supports a recording medium P from a recording surface is provided inside the casing. A platen 2 is provided. Conveying rollers (not shown) for conveying the recording medium P are arranged on the upstream side and the downstream side of the platen 2, and the recording medium P is not recorded by rotating these conveying rollers. The surface is conveyed from the upstream side toward the downstream side while being supported by the platen 2. Here, the conveyance direction of the recording medium P is defined as a sub-scanning direction A.

  A plurality of ink tanks 3 are arranged for each color below one side of the platen 2 in the direction orthogonal to the sub-scanning direction A. Each ink tank 3 is replaceable, and each color ink is stored inside each ink tank 3.

  A long guide rail 4 extending in a direction perpendicular to the sub-scanning direction A is disposed above the platen 2. Here, the direction in which the guide rail 4 extends is defined as a main scanning direction B. A carriage 5 is supported on the guide rail 4, and the carriage 5 can reciprocate in the main scanning direction B while being guided by the guide rail 4.

  A plurality of recording heads 6, 6,... For ejecting ink toward the recording medium P are mounted on the carriage 5. Each recording head 6 and each ink tank 3 are connected to each other according to the type of ink through an ink supply pipe 7 formed of a tube-like member having flexibility such as rubber. Each color ink can be supplied from each ink tank 3 to each recording head 6.

  The ink supply pipe 7 is provided with a variable pressure pump 8 that can supply ink from each ink tank 3 to each recording head 6. The pressure inside the ink supply pipe 7 can be changed by each transformer pump 8, whereby the amount of ink supplied from each ink tank 3 to each recording head 6 can be appropriately changed.

  As shown in FIG. 2, the plurality of recording heads 6, 6,... Mounted on the carriage 5 are arranged at two ends on the most upstream side (hereinafter, the first stage) in the sub-scanning direction A of the carriage 5. One first white ink recording head 9 and two second white ink recording heads 10 are arranged, and between these, four light yellow ink recording heads 11 and four yellow ink recording heads are arranged. The head 12 is disposed along the main scanning direction B.

  Further, four light magenta ink recording heads 13 and four magenta inks are arranged downstream of the light yellow ink recording head 11 and the yellow ink recording head 12 in the sub-scanning direction A (hereinafter, second stage). Recording heads 14 are arranged along the main scanning direction B, and four light cyan ink recording heads 15 and four cyan ink recording heads 16 are arranged on the downstream side (hereinafter, third stage). Are arranged along the main scanning direction B.

  Further, the downstream side of the light cyan ink recording head 15 and the cyan ink recording head 16 in the sub-scanning direction A (hereinafter referred to as the fourth stage), and the most downstream ends of the carriage 5 in the sub-scanning direction A are Two first transparent ink recording heads 17 and two second transparent ink recording heads 18 are arranged, and between these, four light black ink recording heads 19 and four black ink recording heads are arranged. The recording head 20 is arranged along the main scanning direction B.

  Here, the interval between the first white ink recording head 9 and the second white ink recording head 10 is the pitch P1, and the interval between the light yellow ink recording head 11 and the yellow ink recording head 12 is the pitch P2. The spacing between the light yellow ink recording head 11 and the yellow ink recording head 12 adjacent to each other is set at a pitch P3, the white ink recording heads 9 and 10 and the light yellow ink recording head 11 and the yellow ink adjacent thereto. Assuming that the distance between the recording head 12 and the recording head 12 is a pitch P, the pitches P, P1, P2, and P3 are substantially the same along the main scanning direction B as shown in FIG.

Note that the recording heads 9 and 10 for white ink in the present embodiment are arranged so as to sandwich the recording heads 11 and 12 for light yellow and yellow ink, that is, the recording heads 6 and 6 arranged in a line along the main scanning direction B. 6,... Are disposed at both ends of the most upstream side, and the transparent ink recording heads 17 and 18 sandwich the light black and black ink recording heads 19 and 20, that is, along the main scanning direction B. If the recording heads 6, 6,... Arranged in a line are arranged at both ends on the most downstream side and the white ink is first ejected and the transparent ink is finally ejected, It is not limited to the embodiment.
For example, a white ink recording head is disposed at a position facing the yellow ink recording head 12 with the light yellow ink recording head 11 interposed therebetween, and is opposed to the light black ink recording head 19 with the black ink recording head 20 interposed therebetween. The transparent ink recording head may be disposed at the position where the white ink recording head is disposed, that is, the white ink recording head may be disposed at the most upstream end, and the transparent ink recording head may be disposed at the most downstream end.

  Each recording head 6 is formed in a substantially rectangular parallelepiped shape, and is arranged so that the longitudinal direction of the recording head 6 is parallel to the sub-scanning direction A. These recording heads 6 have a lower surface as an ejection surface, and a plurality of nozzles (not shown) for ejecting ink are arranged in a line in the longitudinal direction.

  The nozzles arranged in each recording head 6 eject ink to be ejected as ink droplets, but one droplet of ink droplets ejected from the white ink recording heads 9 and 10 and the transparent ink recording heads 17 and 18. The per unit ejection amount is larger than the ejection amount per ink droplet ejected from each process color ink recording head 11, 12, 13, 14, 15, 16, 19, 20. .

  The white ink, each process color ink, and the transparent ink in the present embodiment are ultraviolet curable inks, but any of water-based ink, oil-based ink, solvent ink, and solid ink is applicable, and is used for water-based ink and oil-based ink. As the colorant to be used, a pigment or a dye can be applied.

  The process color ink in this embodiment includes four standard inks of yellow (Y), magenta (M), cyan (C), and black (K), light yellow (LY), light magenta (LM), and light cyan ( LC) and light black (LK), which is a total of 8 color inks. In the present embodiment, eight colors of ink are used as process color inks, but it is not always necessary to use eight colors of ink as process color inks, and at least one of the eight colors is used as a process color ink. May be.

  The recording medium R in the present embodiment is, for example, a transparent or translucent resin film, and the resin is preferably PET (polyethylene terephthalate), PS (polystyrene), PP (polypropylene), or the like.

Next, the operation of this embodiment will be described.
When predetermined image information is sent to the inkjet recording apparatus 1, the recording medium R is intermittently transported in the sub-scanning direction A in the sub-scanning direction A while the non-recording surface is supported by the platen 2, and the initial stage The carriage 5 waiting at the position moves along the forward direction B1.
At this time, the recording heads 6, 6,... Arranged in the first stage on the recording area are the first white ink recording head 9, the light yellow ink recording head 11, the yellow ink recording head 12, The two white ink recording heads 10 pass in order, and ink is ejected from the first white ink recording head 9, the light yellow ink recording head 11, and the yellow ink recording head 12. Ink is not ejected from the second white ink recording head 10.
Thereafter, the carriage 5 that has moved along the forward direction B1 returns to the initial position when it reaches the final position in the forward direction B1. At this time, the recording medium R is in a stopped state.
Further, the recording medium R moves by a fixed amount along the sub-scanning direction A and stops, and the series of operations described above is repeated as appropriate.

  Next, the recording heads 6, 6,... Arranged in the second stage pass through the recording area in the order of the light magenta ink recording head 13 and the magenta ink recording head 14, and the light magenta. Ink is ejected from the ink recording head 13 and the magenta ink recording head 14, and a series of operations consisting of a certain amount of movement and stop of the recording medium R and reciprocation of the carriage 5 in the forward direction B1 and the backward direction B2. Is repeated as appropriate.

  Further, on the recording area, the recording heads 6, 6,... Arranged in the third stage pass in the order of the light cyan ink recording head 15 and the cyan ink recording head 16, and the light cyan ink recording. Ink is ejected from the head 15 and the cyan ink recording head 16, and a series of operations including a certain amount of movement and stop of the recording medium R and a reciprocating motion of the carriage 5 in the forward direction B1 and the backward direction B2 are appropriately repeated. Repeated.

  Further, on the recording area, the recording heads 6, 6,... Arranged in the fourth stage are the first transparent ink recording head 17, the light black ink recording head 19, the black ink recording head 20, The ink passes through the two transparent ink recording heads 18 in this order, and ink is ejected from the light black ink recording head 19, the black ink recording head 20, and the second transparent ink recording head 18. Ink is not ejected from the first transparent ink recording head 17.

  Thereafter, a series of operations including a certain amount of movement and stop of the recording medium R and a reciprocating motion of the carriage 5 in the forward direction B1 and the backward direction B2 are repeated as appropriate, and image recording in the recording area is completed.

Note that image recording can be performed by an operation different from the above-described operation under the control of a control unit (not shown), and this recording operation will be described in detail below.
When predetermined image information is sent to the inkjet recording apparatus 1, the recording medium R is intermittently transported in the sub-scanning direction A in the sub-scanning direction A while the non-recording surface is supported by the platen 2, and the initial stage The carriage 5 waiting at the position moves along the forward direction B1.
At this time, in the recording area, the recording heads 6, 6,... Arranged in the first stage are the first white ink recording head 9, the light yellow ink recording head 11, the yellow ink recording head 12, The two white ink recording heads 10 pass in order, and ink is ejected from the first white ink recording head 9, the light yellow ink recording head 11, and the yellow ink recording head 12. Ink is not ejected from the second white ink recording head 10.
Thereafter, the carriage 5 that has moved along the forward direction B1 reaches the final position in the forward direction B1, and the recording medium R moves by a certain amount along the sub-scanning direction A and stops.

Next, the carriage 5 that has reached the final position in the forward direction B1 (the initial position in the return direction B2) moves along the return direction B2.
Here, on the recording area, the recording heads 6, 6,... Arranged in the first stage are the second white ink recording head 10, the yellow ink recording head 12, the light yellow ink recording head 11, The first white ink recording head 9 passes in the order, and ink is ejected from the second white ink recording head 10, the yellow ink recording head 12, and the light yellow ink recording head head 11. Ink is not ejected from the first white ink recording head 9.
Thereafter, the carriage 5 moved along the return path direction B2 reaches the final position in the return path direction B2 (initial position in the forward path direction B1).
Further, the recording medium R moves by a fixed amount along the sub-scanning direction A and stops, and the series of operations described above is repeated as appropriate.

Further, after that, the recording heads 13, 14, 15, 16, 17, 18, 19, and 20 arranged in the second to fourth stages pass through the recording area, and these recording heads. 13, 14, 15, 16, 17, 18, 19, 20, a certain amount of movement and stop of the recording medium R and reciprocation of the carriage 5 in the forward direction B 1 and the backward direction B 2 A series of operations consisting of is repeated as appropriate.
Thereafter, the series of operations described above are performed, and image recording in the recording area is completed.

As described above, according to the ink jet recording apparatus and the ink jet recording method of the present embodiment, after ejecting ink from the first white ink recording head 9, the process color ink recording heads 11, 12, 13, 14, 15, Ink is ejected from at least one process color ink recording head 16, 19, or 20, and then ink is ejected from the transparent ink recording head 18, so that light transmission is prevented by the white ink ejected first. As a result, the image can be clearly highlighted and recorded on the transparent or translucent recording medium R.
In addition, the amount of ink on the surface of the recording medium R can be made uniform by the transparent ink that is finally ejected, and it is possible to prevent the surface of the recording medium R from being uneven, thereby performing a special post-treatment. High-definition images with uniform gloss can be recorded.

  The white ink recording heads 9 and 10, the process color ink recording heads 11, 12, 13, 14, 15, 16, 19, 20 and the transparent ink recording heads 17, 18 are mounted on a single carriage 5. Therefore, with a simple configuration in which the arrangement of the recording head in the carriage 5 is taken into consideration, it is possible to prevent light from being transmitted by the white ink, and to cause unevenness on the surface of the recording medium R by the transparent ink. Thus, the inkjet recording apparatus 1 can be reduced in size and the manufacturing cost can be reduced.

  Further, the white ink recording head 9.10 is disposed at the most upstream ends of the recording heads 6, 6,... Arranged in a line along the main scanning direction B, and the transparent ink recording head 17, 18 are arranged at the most downstream ends of the recording heads 6, 6,... Arranged in a line along the scanning direction B, so that the white ink recording heads 9, 10 and the transparent ink recording heads are disposed. 17 and 18 are arranged on both end sides of the process color ink recording heads 11, 12, 19, and 20 without being arranged in a single line along the main scanning direction B. As a result, it is possible to prevent unevenness on the surface of the device, thereby reducing the size of the device and reducing the manufacturing cost.

  Further, the ejection amount per one drop of ink droplets from the white ink recording heads 9 and 10 and the transparent ink recording heads 17 and 18 corresponds to the process color ink recording heads 11, 12, 13, 14, 15, 16. , 19 and 20, the amount of ink droplets ejected from each recording head 6 is larger than the ejection amount per ink droplet. The occupied area of the ink droplets from the ink recording heads 17 and 18 on the surface of the recording medium R occupies the ink droplets from the process color ink recording heads 11, 12, 13, 14, 15, 16, 19 and 20. By making it larger than the area, it becomes possible to reduce the number or size of the recording heads 9 and 10 for white ink and the recording heads 17 and 18 for transparent ink. Thereby, it is possible to reduce the size and manufacturing cost of the suppression of the ink jet recording apparatus 1.

  Furthermore, since the white ink, the ink of each process color, and the transparent ink are ultraviolet curable inks that are cured by the irradiation of ultraviolet rays, the ink can be efficiently cured by irradiating the ultraviolet rays. Therefore, regardless of the recording medium, a high-definition image can be recorded even on a recording medium having poor ink absorbability such as a resin film.

  Furthermore, since the recording medium R on which the image is recorded is a transparent or translucent resin film, high-viscosity ink is used to prevent the ink from flowing on the surface of the recording medium R. Even in this case, the ink amount on the surface of the recording medium R can be made uniform by the discharged transparent ink, and unevenness on the surface of the recording medium R can be prevented.

  Next, a second embodiment will be described with reference to FIG. However, this embodiment is different from the first embodiment only in the arrangement configuration of the recording head 6, and other configurations including the ink and the recording medium R are the same as those in the first embodiment. It is. Therefore, in the present embodiment, description will be made centering on the arrangement configuration of the recording head 6, and the same reference numerals will be given to the same configuration as in the first embodiment, and detailed description thereof will be omitted.

  As shown in FIG. 3, a plurality of recording heads 6, 6,... Are mounted on the carriage 5, and the most upstream side (hereinafter referred to as the first stage) of the carriage 5 in the sub-scanning direction A is disposed at both ends. Four white ink recording heads 21 are arranged, and on the downstream side (hereinafter, second stage), four light yellow ink recording heads 22 and four yellow ink recording heads 23 are provided. Arranged along the main scanning direction B. At this time, the four white ink recording heads 21 arranged in the first stage have four light yellow ink recording heads 22 and four yellow ink recording heads 23 arranged in the second stage, for a total of eight. Of the two recording heads, the recording heads are arranged so as to be positioned substantially at the center corresponding to the four recording heads arranged at the center.

  Further, four light magenta ink recording heads 24 and four magenta inks are disposed downstream of the light yellow ink recording head 22 and the yellow ink recording head 23 in the sub-scanning direction A (hereinafter, third stage). Are arranged along the main scanning direction B, and on the downstream side (hereinafter referred to as the fourth stage), four light cyan ink recording heads 26, four cyan ink recording heads 27, and Are arranged along the main scanning direction B. Further, four light black ink recording heads 28 and four black ink recording heads 29 are arranged along the main scanning direction B on the downstream side (hereinafter referred to as the fifth stage).

  Further, the downstream side of the light black ink recording head 28 and the black ink recording head 29 in the sub-scanning direction A (hereinafter referred to as the sixth stage) and the most downstream side of the carriage 5 in the sub-scanning direction A are 4 Two transparent ink recording heads 30 are arranged. At this time, the four transparent ink recording heads 30 arranged in the sixth stage are composed of four light black ink recording heads 22 and four black ink recording heads 23 arranged in the fifth stage. Of the two recording heads, the recording heads are arranged so as to be positioned substantially at the center corresponding to the four recording heads arranged at the center.

  Here, the intervals between the light yellow ink recording head 22, the light magenta ink recording head 24, the light cyan ink recording head 26 and the light black ink recording head 28 which are adjacent to each other are set at a pitch P3 and the white ink recording head 21. And the interval between the recording head 30 for transparent ink and the recording head 22 for light yellow ink and the recording head 28 for light black ink adjacent to the recording head 21 for white ink and the recording head 30 for transparent ink is a pitch P. 2, the pitches P and P3 are substantially the same along the sub-scanning direction A.

  Each recording head 6 is formed in a substantially rectangular parallelepiped shape, and the recording head for white ink and the recording head for transparent ink are formed so that the longitudinal direction is shorter than the recording head for each process color ink. Each recording head 6 is arranged so that the longitudinal direction of the recording head 6 is parallel to the sub-scanning direction A. Further, the lower surface of each recording head 6 is an ejection surface, and a plurality of nozzles (not shown) for ejecting ink are arranged in a line in the longitudinal direction.

Next, the operation of this embodiment will be described.
When predetermined image information is sent to the inkjet recording apparatus 1, the recording medium R is intermittently transported in the sub-scanning direction A in the sub-scanning direction A while the non-recording surface is supported by the platen 2, and the initial stage The carriage 5 waiting at the position moves along the forward direction B1.
Here, the white ink recording head 21 arranged in the first stage passes through the recording area, and ink is ejected from the white ink recording head 21.
Thereafter, the carriage 5 that has moved along the forward direction B1 returns to the initial position when it reaches the final position in the forward direction B1. At this time, the recording medium R is in a stopped state.
Further, the recording medium R moves by a fixed amount along the sub-scanning direction A and stops, and the series of operations described above is repeated as appropriate.

  In addition, after that, the recording heads 22, 23, 24, 25, 26, 27, 28, 29, 30 arranged in the second to sixth stages pass through the recording area, and these A certain amount of movement and stop of the recording medium R and the forward direction B1 and the backward direction B2 of the carriage 5 so that ink is ejected from the recording heads 22, 23, 24, 25, 26, 27, 28, 29, 30. A series of operations including the reciprocating motion is repeated as many times as necessary, and the above-described operation is performed to complete image recording in the recording area.

Note that image recording can be performed by an operation different from the above-described operation under the control of a control unit (not shown), and this recording operation will be described in detail below.
When predetermined image information is sent to the inkjet recording apparatus 1, the recording medium R is intermittently transported in the sub-scanning direction A in the sub-scanning direction A while the non-recording surface is supported by the platen 2, and the initial stage The carriage 5 waiting at the position moves along the forward direction B1.
Here, in the recording area, the white ink recording head 21 arranged in the first stage passes over the recording area, and ink is ejected from the white ink recording head 21.
After that, the carriage 5 moved along the forward direction B1 reaches the final position in the forward direction B1, and the recording medium R moves along the sub-scanning direction A by a certain amount and stops.

Next, the carriage 5 that has reached the final position in the forward direction B1 (the initial position in the return direction B2) moves along the return direction B2.
At this time, the white ink recording head 21 arranged in the first stage passes over the recording area, and ink is ejected from the white ink recording head 21.
Thereafter, the carriage 5 moved along the return path direction B2 reaches the final position in the return path direction B2 (initial position in the forward path direction B1).
Further, the recording medium R moves by a fixed amount along the sub-scanning direction A and stops, and the series of operations described above is repeated as appropriate.

In addition, after that, the recording heads 22, 23, 24, 25, 26, 27, 28, 29, 30 arranged in the second to sixth stages pass through the recording area, and these A certain amount of movement and stop of the recording medium R and the forward direction B1 and the return direction B2 of the carriage 5 so that ink is ejected from the heads 22, 23, 24, 25, 26, 27, 28, 29, 30. A series of operations consisting of the reciprocating motions is repeated as appropriate.
Further, the series of operations described above are performed, and image recording in the recording area is completed.

As described above, according to the ink jet recording apparatus and the ink jet recording method of the present embodiment, after ejecting ink from the white ink recording head 21, the process color ink recording heads 22, 23, 24, 25, 26, 27, 28 and 29, ink is ejected from at least one process color ink recording head, and then ink is ejected from the transparent ink recording head 30. Therefore, it is possible to prevent light from being transmitted by the first white ink ejected. As a result, the image can be clearly highlighted and the image can be recorded on the transparent or translucent recording medium R.
In addition, the amount of ink on the surface of the recording medium R can be made uniform by the transparent ink that is finally ejected, and it is possible to prevent the surface of the recording medium R from being uneven, thereby performing a special post-treatment. High-definition images with uniform gloss can be recorded.

  Since the white ink recording head 21, the process color ink recording heads 22, 23, 24, 25, 26, 27, 28, 29 and the transparent ink recording head 30 are mounted on a single carriage, With a simple configuration that considers the arrangement of the recording head in the carriage, it is possible to prevent light from being transmitted by the white ink, and it is possible to prevent the surface of the recording medium R from being uneven due to the transparent ink, As a result, it is possible to reduce the size of the ink jet recording apparatus and the manufacturing cost.

  Next, a third embodiment will be described with reference to FIG. However, this embodiment is different from the first embodiment in the configuration of the recording head 6, and the other configurations including the ink and the recording medium R are the same as those in the first embodiment. . Therefore, in the present embodiment, description will be made with a focus on the configuration of the recording head 6, and the same reference numerals are given to the same configurations as those in the first embodiment, and detailed description thereof will be omitted.

  As shown in FIG. 4, the inkjet recording apparatus 1 in the present embodiment includes a platen 2. White ink line head 31, light yellow line head 32, yellow line head 33, light magenta line head 34, and magenta line head 35 above the platen 2 from upstream to downstream in the sub-scanning direction A. A light cyan line head 36, a cyan line head 37, a light black line head 38, a black line head 39, and a transparent ink line head 40 are provided.

  Each line head is formed in a substantially rectangular parallelepiped shape, and extends in a direction orthogonal to the conveyance direction of the recording medium P over substantially the entire width of the recording medium R. Each line head has an ejection surface on the lower surface, and a number of nozzles (not shown) that eject ink as ink droplets are arranged. Here, the direction in which each line head extends is defined as an extending direction C.

  The ink jet recording apparatus 1 according to the present embodiment includes one line head for each ink color, but is not particularly limited, and includes a plurality of line heads for each ink color. May be. In the case where a plurality of line heads are provided for each ink color, the arrangement of each line head is such that the white ink line head 31 is arranged on the most upstream side in the sub-scanning direction A, and the transparent ink is used on the most downstream side. If the line head 40 is arrange | positioned, it will not specifically limit.

Next, the operation of this embodiment will be described.
When predetermined image information is sent to the ink jet recording apparatus 1, the transport roller rotates, and the upper part of the platen 2 is continuously moved in the sub-scanning direction A while the recording medium R is supported on the non-recording surface by the platen 2. Be transported.

Here, the recording medium R passes below the white ink line head 31 disposed on the most upstream side in the sub-scanning direction A, and the white ink is ejected from the white ink line head 31 onto the recording area. The
Thereafter, the recording medium R passes below the process color line heads 32, 33, 34, 35, 36, 37, 38, 39 disposed downstream of the white ink line head 31 in the sub-scanning direction A. In addition, ink is ejected from the process color line head onto the recording area.
Further, the transparent ink passes through the lower side of the transparent ink line head 40 disposed on the most downstream side in the sub-scanning direction A among the line heads, and the transparent ink is discharged onto the recording area from the transparent ink line head.
Thereafter, the series of operations described above is performed, and image recording in the recording area is completed.

As described above, according to the ink jet recording apparatus and the ink jet recording method of the present embodiment, the white ink recording head 31, the process color recording heads 32, 33, 34, 35, 36, 37, 38, 39 and the transparent ink recording. Even if the head 40 is a so-called line print type inkjet recording apparatus, which is a line head disposed in a direction orthogonal to the conveyance direction of the recording medium R, after ejecting ink from the white ink line head 31, Ink is ejected from at least one process color ink line head among the process color ink line heads 32, 33, 34, 35, 36, 37, 38, 39, and then ink is ejected from the transparent ink line head 40. Therefore, the white ink that is ejected first prevents light transmission. DOO becomes possible, thereby, the image it is possible to clearly highlight may be an image recorded on a transparent or semi-transparent recording medium R.
In addition, the amount of ink on the surface of the recording medium R can be made uniform by the transparent ink that is finally ejected, and it is possible to prevent the surface of the recording medium R from being uneven, thereby performing a special post-treatment. High-definition images with uniform gloss can be recorded.

  Further, since the white ink recording head 31, the process color ink recording heads 32, 33, 34, 35, 36, 37, 38, 39 and the transparent ink recording head 40 are line heads, the arrangement of the line heads is changed. With a simple configuration, it is possible to prevent light from being transmitted by the white ink, and it is also possible to prevent the surface of the recording medium R from being uneven due to the transparent ink. The size and manufacturing cost can be reduced.

  In the first embodiment and the second embodiment described above, the white ink recording head 6, the process color ink recording head 6, and the transparent ink recording head 6 have different ink forms. It is also possible to eject inks having different heating temperatures from the white ink recording head 6 and the process color ink recording head 6. In this case, the pitch P may be wider than at least one of the pitches P1, P2, and P3.

  For example, the pitch shown in FIG. 2 may be changed to the pitch shown in FIG. In FIG. 5, since the pitch P1 is narrower than the pitch P, the white ink recording heads are in a dense state, and the heating temperature of the white ink in the white ink recording head 6 can be made uniform. Further, in FIG. 5, since the pitches P2 and P3 are narrower than the pitch P, the process color ink recording heads and all the process color ink recording heads are in a denser state, and the heating temperature of the process color ink is uniform. Can be achieved. Furthermore, since the white ink recording head 6 and the process color ink recording head 6 can achieve a uniform heating temperature at a portion that affects the ink ejection, the one recording head 6 has the ink heating temperature. The other recording head 6 having a different difference is hardly affected by the temperature difference. Thereby, ink can be ejected from each recording head 6 at a more optimal heating temperature.

  Also in the example shown in FIG. 3, the pitch P may be wider than the pitch P <b> 3 when the white ink recording head 6 and the process color ink recording head 6 eject inks having different heating temperatures. . Even in this case, ink can be ejected from each recording head 6 at a more optimal heating temperature.

  Furthermore, in the first embodiment, the second embodiment, and the third embodiment, each color ink is ejected from each process color ink recording head, but the ink is not necessarily supplied from all process color ink recording heads. The ink may be discharged from at least one process color ink recording head among the process color ink recording heads. In addition, the recording head 6 in the first embodiment and the second embodiment is shown in FIGS. 2 and 3 in which four recording heads 6 are assembled to form one aggregate. The number of recording heads in the aggregate of recording heads 6 need not be four, the number of recording heads in each aggregate of recording heads 6 can be changed as appropriate, and a plurality of aggregates of recording heads 6 are aggregated. Instead of the recording head, it may be configured as a single unit.

  Furthermore, in the first embodiment, the second embodiment, and the third embodiment, the background color is white. However, the present invention is not limited to this. In other words, instead of the white ink recording heads 9, 10, 21, and 31 that discharge white ink, a recording head that discharges ink of a color other than white may be arranged so that a special color other than white may be used as the background color. .

  Here, the special color is a color other than a combination of the above process colors and process colors. For example, in each process color such as gold, silver, blue, green, red, red beans, ocher, dark red, etc. It means a color that cannot be expressed or a color that cannot be expressed by combining each process color.

  Furthermore, in the first embodiment, the second embodiment, and the third embodiment, the white ink, each process color ink, and the transparent ink are ultraviolet curable inks, but the special color ink is also ultraviolet curable. Type ink may be used. When these white inks, process color inks, transparent inks and special color inks are ultraviolet curable inks, an ultraviolet irradiation device 41 is provided downstream of the platen 2 in the sub-scanning direction A as shown in FIG. Then, the ink is ejected from the recording head 6 while being sucked and held by the platen 2, and the ultraviolet light may be irradiated from the ultraviolet irradiation device 41 to the ink landed on the recording medium R conveyed by the conveying roller 42. . As a result, the ink discharged onto the recording medium R can be instantaneously cured.

  Further, when at least one of water-based ink, oil-based ink, solvent ink, and solid ink is used as the white ink, each process color ink, transparent ink, and special color ink, as shown in FIG. A fixing mechanism 43 is provided on the downstream side in the sub-scanning direction A so that ink is ejected from the recording head 6 while being sucked and held by the platen 2, and the ink that has landed on the recording medium R conveyed by the conveying roller 42 is applied. Various actions may be performed from the fixing mechanism 43.

  The various actions from the fixing mechanism 33 are, for example, radiation by infrared rays, heat transfer by a heater, drying by hot air, and the like, and thereby ink that has landed on the recording medium R is instantaneously applied. It can be fixed on the recording medium R.

It is the schematic which shows the principal part of the inkjet recording device in 1st and 2nd embodiment. It is a top view which shows the arrangement | positioning relationship between the white head group, each process color head group, and a transparent head group in 1st embodiment. It is a top view which shows the arrangement | positioning relationship between the white head group, each process color head group, and a transparent head group in 2nd embodiment. It is the schematic which shows the principal part of the inkjet recording device in 3rd embodiment. It is a top view which shows the modification of the arrangement | positioning relationship between the white head group, each process color head group, and a transparent head group in 1st embodiment. It is the schematic which shows the 1st modification of the inkjet recording device which concerns on this invention. It is the schematic which shows the 2nd modification of the inkjet recording device which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Inkjet recording device 5 Carriage 6 Recording head 9, 10, 21 White recording head 11, 12, 13, 14, 15, 16, 19, 20, 22, 23, 24, 25, 26, 27, 28, 29 Process Color ink recording heads 17, 18, 30 Transparent ink recording head 31 White ink line heads 32, 33, 34, 35, 36, 37, 38, 39 Process color ink line head 40 Transparent ink line head A Scanning direction B Main scanning direction C Extension direction B1 Forward direction B2 Return direction R Recording medium

Claims (12)

An inkjet recording apparatus comprising a plurality of recording heads that eject ink onto a recording medium,
The plurality of recording heads include a background color ink recording head for discharging background color ink, a process color ink recording head for discharging process color inks, and a transparent ink recording for discharging transparent ink. Composed of a head and
The transparent ink recording head is disposed on the most downstream side in the conveyance direction of the recording medium,
2. The ink jet recording apparatus according to claim 1, wherein the background color ink recording head is disposed upstream of the transparent ink recording head in the transport direction of the recording medium. A carriage that scans in a direction orthogonal to the conveyance direction of the recording medium;
2. The ink jet recording apparatus according to claim 1, wherein the carriage includes the background color ink recording head, the process color ink recording head, and the transparent ink recording head. The background color ink recording heads are arranged at one or both ends on the most upstream side of the recording heads arranged in a line along the scanning direction,
The said transparent ink recording head is arrange | positioned at the other end or both ends of the most downstream side of the recording head arrange | positioned in a line along the said scanning direction, The Claim 1 or Claim 2 characterized by the above-mentioned. Inkjet recording device.   The background color ink recording head, the process color ink recording head, and the transparent ink recording head are arranged such that the longitudinal side of each recording head is orthogonal to the transport direction of the recording medium. The inkjet recording apparatus according to claim 1, wherein: Ink to be ejected from each recording head of the background color ink recording head, the process color ink recording head, and the transparent ink recording head is ejected as ink droplets;
The amount of ink droplets ejected from at least one of the background color ink recording head and the transparent ink recording head is one of the ink droplets ejected from the process color ink recording head. The inkjet recording apparatus according to claim 1, wherein the inkjet recording apparatus has a larger discharge amount per droplet.   6. The inkjet recording apparatus according to claim 1, wherein the background color ink, the process color ink, and the transparent ink are ultraviolet curable inks.   The ink jet recording apparatus according to claim 1, wherein the carriage includes an ultraviolet irradiation device that irradiates each ink droplet landed on the recording medium with ultraviolet rays.   The recording medium on which an image is recorded by the background color ink, the process color ink and the transparent ink is a transparent or translucent resin film. An ink jet recording apparatus according to claim 1. A recording medium transporting process for transporting the recording medium to a recording area where ink is ejected;
For each pixel on the recording surface of the conveyed recording medium, the background color ink is first ejected from the background color ink recording head and finally the transparent ink is ejected from the transparent ink recording head. An ink jet recording method comprising: an ink discharge step of forming a lowermost layer made of the background color ink and an uppermost layer made of the transparent ink on a surface.   The ink ejection step ejects at least one of the process color inks, and on the pixels from which the process color ink is ejected, after ejecting the background color ink, The ink jet recording method according to claim 9, wherein the process color ink is discharged before discharging.   The amount of ink droplets ejected from at least one of the background color ink recording head and the transparent ink recording head is one droplet of ink droplets ejected from the process color ink recording head. 11. The ink jet recording method according to claim 9, wherein the ink jet recording method is larger than a per unit discharge amount. For the background color ink, the process color ink and the transparent ink, ultraviolet curable ink is used,
12. The method according to claim 9, further comprising an ultraviolet irradiation step of irradiating each ink droplet landed on the recording medium with ultraviolet light and curing the ink droplet after the ink ejection step. The inkjet recording method as described in any one of these.

Images