JP2780280B2 - Color inkjet recording method and apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Summary] The present invention relates to a color ink jet recording method and an apparatus for obtaining a mixed color by superimposing at least two colors selected from three primary color inks of yellow, magenta and cyan. An object of the present invention is to provide a color ink jet recording method and apparatus capable of clarifying mixed color printing with color inks and improving the color development of the mixed colors, and among three primary color inks of yellow, magenta and cyan. A color ink jet recording method is characterized in that the recording priority when obtaining a mixed color by superimposing at least two selected color inks is cyan, magenta, and yellow. At least two color inks selected from the three primary color inks A color ink jet recording apparatus in which the arrangement priority when arranging the print heads for the color inks is a print head for cyan, a print head for magenta, and a print head for yellow in the printing movement direction of the print head carriage. Is configured.

[Industrial applications]

The present invention relates to a color ink jet recording method for obtaining a mixed color by superimposing at least two color inks selected from three primary color inks of yellow, magenta and cyan, and an apparatus therefor.

[Conventional technology]

It is already known to carry out color recording using an ink jet recording technique. In this case, two colors selected from three primary colors of yellow, magenta and cyan are usually used as color inks. This is because a predetermined mixed color can be obtained by using at least two of the three primary colors. That is, as is well known,
A mixed color of red is obtained depending on the superposition of yellow and magenta, a green is obtained by superimposing yellow and cyan, and a blue is obtained by superimposing magenta and cyan. Therefore, in a color ink jet recording apparatus configured to perform color recording using all three primary colors of yellow, magenta and cyan, its print head carriage is provided with a yellow print head, a magenta print head and a cyan print head. As a result, the colors are overlapped as described above, and a desired mixed color is obtained. As is well known to those skilled in the art, black is theoretically obtained by using all three primary colors of yellow, magenta, and cyan. However, in practice, clear black cannot be obtained. Therefore, a black print head for black ink is used in addition to the color print head.

By the way, in the conventional color ink jet recording technique, when obtaining the above-described mixed colors, colors are customarily overlapped in the order of yellow, magenta, and cyan. For example, in a print head of a color ink jet recording apparatus using all three primary colors of yellow, magenta and cyan, a yellow print head, a magenta print head and a cyan print head are sequentially arranged in the printing direction. In order to obtain the mixed color of magenta ink, after the yellow ink jet droplet is applied to the printing paper, the magenta ink jet droplet is superposed thereon. Similarly, to obtain a green mixed color, cyan is superimposed on yellow, and to obtain a blue mixed color, cyan is superimposed on magenta.

[Problems to be solved by the invention]

By the way, in the conventional color ink jet recording technology as described above, there has been no description about the mixed color printing quality of red, green and blue. The present inventors have found that the single color printing of yellow, magenta or cyan is extremely sharp and clear, while the mixed color printing of red, green and blue is blurred and unclear. I found something.

Then, the present inventors investigated the cause of why the mixed color printing of red, green, and blue became unclear, and found the following as the cause. That is, when the ink-jet droplets of the first ink are applied to the printing paper, and then the ink-jet droplets of the second ink are superimposed thereon, the periphery of the printing location is bordered by the second ink, It was revealed that when the border portion of the second ink appeared to be mixed with the mixed color portion of the first ink and the second ink, the entire print became blurred and unclear.

Referring to FIG. 2, the first ink and the second ink distribution when the inkjet ink droplets of the first ink are applied to the printing paper and then the inkjet ink droplets of the second ink are superimposed thereon. The cross section of the printing location is shown to clarify. In FIG. 2, the first ink is distributed only in the shaded area, and the second ink is distributed in both the shaded area and the shaded area. Referring to FIG. 3A,
The first and second ink distributions shown in FIG. 2 are shown as the ink density distribution in the thickness direction, that is, the depth direction (Z) of the printing paper, and with reference to FIG. 3B, it is shown in FIG. The first and second ink distributions are shown as the ink density distribution in the paper surface direction (x) of the printing paper. 3A and 3B, the solid line shows the density distribution of the first ink, and the broken line shows the density distribution of the second ink. As can be seen from FIGS. 2, 3A and 3B, it can be seen that the mixed color area of the first ink and the second ink is bordered on the paper surface of the printing paper by the second ink. .

In short, when magenta is overlaid on yellow, the red mixed color region of yellow and magenta is bordered by magenta, and the border of magenta appears to be fused with the red mixed color region, so that the red mixed When the color area is blurred and indistinct, and yellow and cyan overlap, the green-based mixed color area of yellow and cyan is bordered by cyan, and the cyan bordering area blends with the green-based mixed color area. Therefore, when the green mixed color area is blurred and unclear, and when magenta is overlaid with cyan, the blue mixed color area of magenta and cyan is bordered by cyan, and the cyan border is obtained. The portion appears to be fused with the blue-based mixed color region, so that the blue-based mixed color region is blurred and unclear.

When magenta is overlaid on yellow, the second
As is apparent from the figure, since the magenta goes under the yellow and the yellow is emphasized, the mixed color becomes dark orange rather than red. Similarly, when cyan is superimposed on yellow, cyan goes around under yellow and emphasizes yellow,
The mixed color is closer to yellow-green than green.
Also, when cyan is superimposed on magenta,
The mixed color becomes closer to purple rather than blue because cyan flows under magenta and emphasizes magenta. Of course, by adjusting the densities of yellow, magenta and cyan, red is added as a mixed color when magenta is overlaid on yellow, and the edge is overlaid on magenta when cyan is overlaid on yellow. It is possible to obtain blue when cyan is superimposed, but in this case, there is a problem that the color balance when yellow, magenta, and cyan are recorded alone becomes poor.

In short, it has been clarified that in the conventional color ink jet recording technique, the original red, green and blue colors are not generated by the superposition of the three primary colors of yellow, magenta and cyan.

Accordingly, an object of the present invention is a color ink jet recording method and apparatus for superimposing at least two colors selected from the three primary colors of yellow, magenta and cyan as color inks to obtain a mixed color, and using the three primary colors. It is an object of the present invention to provide a color ink jet recording method and apparatus capable of clarifying mixed color printing and improving the color developability of those mixed colors.

[Means for solving the problem]

According to the present invention, the print head reciprocates in the main scanning direction, but performs a printing operation by ejecting ink only at the time of forward movement, does not perform a printing operation at the time of backward movement, and has three colors of yellow, magenta and cyan. In a color ink jet recording method in which a mixed color is obtained by superimposing at least two color inks selected from primary color inks, the recording priorities at the time of overlapping such color inks are cyan, magenta, and yellow. It is characterized by being done.

Further, according to the present invention, the print head reciprocates in the main scanning direction, but performs a printing operation by ejecting ink only at the time of forward movement, does not perform a printing operation at the time of backward movement, and performs printing at the time of performing a printing operation. The print head for cyan, the print head for magenta, and the print head for yellow are arranged in this order with respect to the moving direction of the head, and at least two colors selected from the three primary color inks of yellow, magenta, and cyan. In a color ink jet recording apparatus that obtains a mixed color by superimposing the color inks, the arrangement priority when arranging the print heads for the color inks on the print head carriage is oriented toward the print moving direction of the print head carriage. And a cyan print head, a magenta print head, and a yellow print head.

[Action]

In the color ink jet recording method according to the present invention, the recording priority when obtaining a mixed color by overlapping at least two color inks selected from the three primary color inks of yellow, magenta and cyan is cyan. , Magenta and yellow, the blue mixed color area obtained by overlapping cyan and magenta is bordered by magenta, and the green mixed color area obtained by overlapping cyan and yellow is yellow. The red mixed color area which is bordered and obtained by overlapping magenta and yellow will be bordered by yellow (FIG. 2,
3A and 3B), the blue mixed color region does not appear to be fused with the magenta border portion, and both the green mixed color region and the red mixed color region are yellow bordered. It does not seem to blend with the part. Further, in the color ink jet recording method according to the present invention, since magenta is superimposed on cyan,
Because magenta wraps around under cyan, the effect of magenta is weakened when blue-based mixed colors are developed, compared to cyan over magenta, and yellow over cyan or magenta as well. When yellow or yellow mixed colors are mixed, yellow or magenta is mixed so that cyan or magenta is superimposed on yellow or magenta. Yellow's influence will be weakened.

In the color ink jet recording apparatus according to the present invention, the arrangement when the print heads for at least two color inks selected from the three primary color inks of yellow, magenta and cyan are arranged on the print head carriage. Since the priority order is set to the cyan print head, magenta print head, and yellow print head in the printing movement direction of the print head carriage, when obtaining a blue-based mixed color of cyan and magenta, When magenta is superimposed on top to obtain a green mixed color of cyan and yellow, yellow is superimposed on cyan, and when red mixed color of magenta and yellow is obtained, Is superimposed on yellow. Therefore, as described above, the blue-based mixed color region obtained by overlapping cyan and magenta is bordered by magenta,
The green mixed color area obtained by overlapping cyan and yellow will be bordered by yellow, and the red mixed color area obtained by overlapping magenta and yellow will be bordered by yellow. The mixed color region does not appear to blend with the border of magenta, and neither the mixed green region nor the mixed red region appears to blend with the border of yellow. Further, in the color ink jet recording apparatus according to the present invention, when a blue-based mixed color is formed, magenta is superimposed on cyan, so that the effect of magenta is weakened, and similarly, a green-based mixed color or a red-based mixed color is formed. At times, yellow is overlaid on cyan or magenta, so the effect of yellow will be reduced.

〔Example〕

Next, an embodiment of a color ink jet recording apparatus according to the present invention will be described with reference to FIG.

FIG. 1 is a perspective view partially showing only a printing section of a color ink jet recording apparatus according to the present invention. The printing section includes a platen 10 rotatably supported by a suitable frame structure (not shown). Is provided. Platen
A paper holding rod 12 is incorporated in the printer 10 in a well-known manner, and the printing paper S is fed at a predetermined line interval by driving the platen 10 while being securely held on the platen 10 by the paper holding rod 12.

As shown in FIG. 1, a pair of guide rods 14, 14 are arranged in parallel along the platen 10, and each guide rod may be supported by a suitable frame structure as described above. A print head carriage 16 is slidably mounted on the pair of guide rods 14, so that the print head carriage 16 can move along the platen 10. The print head carriage 16 incorporates a well-known appropriate drive mechanism, for example, a belt drive mechanism, but such a drive mechanism is not directly related to the present invention and is not shown in FIG. .

The print head carriage 16 has an inkjet type 4
One of the print head 18 _C, is 18 _M, 18 _Y and 18 _B are mounted, the print head 18 _C those for cyan, the print head 18 _M is one for magenta, the print head 18 _Y is one for yellow, print head 18 _B is for black. It should be noted here that the print heads 18 _C and 18 on the print head carriage 16 are different.
Sequence order of _M and 18 _Y. That is, the cyan printing head 18 _C printing toward the moving direction (arrow W) of the print head carriage 16 is placed at the beginning and then is disposed printhead 18 _M for magenta, the print head 18 _Y is for yellow to the next It is to be arranged. Therefore, when performing blue recording with cyan and magenta, magenta is superimposed on cyan, and when performing green recording with cyan and yellow, yellow is superimposed on cyan.
When red recording is performed between magenta and yellow, yellow is superimposed on magenta. In this embodiment, for the location of the black printing head 18 _B, but has a rearmost in the print direction of movement of the print head carriage 16 (arrow W), black printing head 18 _B is located in the forwardmost Needless to say, this may be done.

Four printing heads 18 _C, 18 _M, 18 _Y and 18 respectively ink intake tube 20 _C for _B, 20 _M, 20 _Y and 20 _B are provided, are in these ink intake pipe flexible ink supply tube Connected. The ink supply tubes are bundled as a tube bundle 22 and connected to predetermined ink supplies (not shown): a cyan supply, a magenta supply, a yellow supply, and a black supply.

Next, the operation of the above-described color inkjet recording apparatus will be described. In addition, as an example, the printing paper S
The case where the alphabets "A", "B" and "C" are printed in blue, green and red, respectively, will be described above.

First, the print head carriage 16 is placed at the print start position (that is, the leftmost position in FIG. 1), and the print head carriage 16 is moved in the direction of arrow W from the print start position. During this movement of the print head carriage 16, first, it is activated when the print head 18 _C passes the printing position of the alphabet "A", printed the letters "A" in cyan, followed by the print head 18 _C
Is also activated when passing through the printing position of the alphabet "B", and the alphabet "B" is printed in cyan. At this time, the print head _{18M is} also operated to print the magenta alphabet "A" on the cyan alphabet "A", so that the alphabet "A" is recorded in blue.

Is again actuated when the print head 18 _M passes the printing position of the alphabet "C", the alphabet "C" were printed in magenta, while the print head 18 _Y be actuated, yellow on the alphabet "B" of cyan Is printed, and as a result, the alphabet "B" is recorded in green.

It is activated again when the print head 18 _Y passes the printing position of the alphabet “C”, and prints the yellow alphabet “C” on the magenta alphabet “C”, and as a result, the alphabet “C” is recorded in red. Will be done.

As is evident from the previous record, the blue alphabet "A" is bordered by magenta, but the magenta border does not seem to blend with the blue alphabet "A" and the blue alphabet "A""Is clearly visible. On the other hand, the green alphabet “B” and the red alphabet “C” are both bordered by yellow,
The yellow border does not seem to blend with the green alphabet "B" or the red alphabet "C", and the green alphabet "B" and the red alphabet "C" can be clearly seen. .

As described above, in the present invention, the print head carriage 16
When is moved only in the direction of arrow W, a printing operation is performed, and when it is moved in the direction opposite to arrow W, printing is not performed. Further, in the above-described embodiment, the print heads 18 _C , 18 _M and 18 _Y corresponding to the three primary color inks of yellow, magenta and cyan are used, however, at least two of these print heads are used. It is evident from the following claims that they are intended to be included within the scope of the invention.

〔The invention's effect〕

As is apparent from the above description, according to the present invention, when obtaining a blue-based mixed color of cyan and magenta, superimposing magenta on cyan and obtaining a green-based mixed color of cyan and yellow In this case, yellow is superimposed on cyan, and when a red-based mixed color of magenta and yellow is obtained, yellow is superimposed on magenta, thereby bordering the blue-based mixed color area with magenta. Since the green mixed color area is bordered with yellow and the red mixed color area is bordered with yellow, the blue mixed color area does not seem to blend with the magenta border, and the green mixed color area does not appear. Also, the red-based mixed color area does not seem to blend with the yellow border. Therefore, the blue-based mixed color region, the green-based mixed color region, and the red-based mixed color region can be clearly recognized. On the other hand, when a blue-based mixed color is formed, magenta wraps around the lower side of cyan, so that the effect of magenta is weakened, the blue-forming property is improved, and when a green-based mixed color or a red-based mixed color is formed, Yellow goes under cyan or magenta,
As a result, the effect of the yellow is weakened, and the coloring of green or red is improved.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a printing unit of a color ink jet recording apparatus according to the present invention, and FIG. 2 is a drawing in which an ink jet droplet of a first ink is applied to a printing paper and then a second ink droplet is applied thereon.
FIG. 3A is a schematic cross-sectional view showing the distribution of the first ink and the second ink when the ink-jet droplets of the first ink and the second ink are superimposed.
FIG. 3B is a graph showing the first and second ink distributions shown in FIG. 2 as an ink density distribution in the thickness direction of the printing paper, ie, the depth direction (Z). FIG. 3B is a graph showing the first and second ink distributions shown in FIG. FIG. 9 is a graph showing a second ink distribution as an ink density distribution in a paper surface direction (x) of a printing paper. 10 ... Platen, 12 ... Paper holding rod, 14 ... Guide rod, 16 ... Print head carriage, _18C / _18M / _18Y / 1
8 _B ... print head, 20 _C / 20 _M / 20 _Y / 20 _B ... ink intake tube, 22 ... tube bundle.

──────────────────────────────────────────────────続 き Continuation of front page (72) Inventor Akira Nakazawa 1015 Uedanaka, Nakahara-ku, Kawasaki City, Kanagawa Prefecture Inside Fujitsu Limited (56) References JP-A-58-179652 (JP, A) JP-A-62-161541 (JP, A) JP-A-1-237146 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) B41J 2 / 13,2 / 21

Claims (2)

(57) [Claims] When the print head reciprocates in the main scanning direction, the printing operation is performed by ejecting ink only at the time of forward movement, the printing operation is not performed at the time of backward movement, and three primary colors of yellow, magenta and cyan are provided. In the color ink jet recording method for obtaining a mixed color by superimposing at least two color inks selected from the above color inks, the recording priorities at the time of overlapping such color inks are set to cyan, magenta and yellow. A color ink jet recording method characterized by the above-mentioned. The print head reciprocates in the main scanning direction, but performs a printing operation by ejecting ink only at the time of forward movement, does not perform a printing operation at the time of backward movement, and moves the print head at the time of performing the printing operation. A printhead for cyan, a printhead for magenta, and a printhead for yellow are arranged in this order, and at least two color inks selected from the three primary color inks yellow, magenta, and cyan Print head carriage (16) in a color ink jet recording apparatus for obtaining a mixed color by superposing
SEQ priority cyan printing head toward a printing direction of movement of the print head carriage at the time of arranging the print head for color ink according to the above (18 _C), magenta printing head (18 _Y), printing yellow A color ink jet recording apparatus comprising a head ( _18B ).