JP3079056B2 - Color inkjet recording apparatus and color inkjet recording ink set - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention is a color ink-di for performing color printing by using an ink jet head
Jet recording apparatus and color jet used in the apparatus
Print recording ink set .

[0002]

2. Description of the Related Art A conventional color ink jet recording method uses, for example, four ink jet heads for individually ejecting black, cyan, magenta, and yellow inks, and discharge energy generating elements such as piezoelectric elements and heating elements. There is a type in which ink droplets are ejected by the generation of pressure due to pressure, and color recording is performed on recording paper.

In this case, the black ink is used only in a single color as in the case of printing characters such as alphabets and numbers in FIG. 3, and black and other colors are not superimposed. On the other hand, color (yellow, magenta, cyan, etc.) inks perform overprinting. As described above, in the color recording, the usage conditions are different between the black ink and the other color inks.

[0004]

However, in such a conventional color ink jet recording method,
When color recording is performed, for example, when a solid printing area recorded in green (cyan ink and yellow ink) and a solid printing area recorded in red (yellow ink and magenta ink) come into contact with each other, two colors of ink are printed on recording paper. Since the inks come into contact with each other in a state, the inks are mixed at a boundary portion, and there is a problem that the printing quality is greatly reduced (see FIG. 3).

SUMMARY OF THE INVENTION The present invention has been made in view of such conventional problems, and has been made in consideration of the above-mentioned problems, and provides a color ink jet recording apparatus capable of performing high-quality color recording.
It is intended to provide an ink set .

[0006]

SUMMARY OF THE INVENTION According to the present invention , a black ink is a single color and a desired color is obtained by an ink jet head for ejecting a plurality of color inks and a black ink individually.
In color ink jet recording apparatus for performing recording on a recording sheet by superimposing each other when that, at least
Depending on the content of the color ink, the water resistance on the recording paper depends on the content.
Dissolving agent to shorten the fixing time of the ink on the recording paper.
Additives in the color ink
The content of the additive material depends on the fixing time of the color ink on the recording paper.
An amount that is less than the time during which no color mixing between different colors occurs
And the content of the additive material in the black ink is
Less than the content of the additive material in the ink,
The action of the black ink to dissolve the waterproofing agent on the recording paper
Weakens the action of dissolving the waterproofing agent.

[0007] By the way, when the ink is in a liquid state on the recording paper,
Inks come into contact with each other in a state
In addition, the print quality deteriorates. So, on the ink recording paper
The results of determining the relationship between the penetration time of
It is shown in the table.

[0008]

[Table 1]

From these results, it has been clarified that when the fixing time of the color ink is set to a predetermined time, for example, 10 seconds or less, good print quality with little mixing of colors can be obtained. In the present invention, the fixing time of the color ink is equal to the predetermined time.
So that the additive material is contained. This additive material contains
Melts the waterproofing agent on the recording paper, depending on the amount
Reduces the fixing time of the ink on the recording paper.
You. And for black ink, the content of the additive material
The color ink by making it less than that of the color ink.
Weakens the effect of dissolving the waterproofing agent on the recording paper compared to ink
You. Thus, the color ink and the black ink
By defining the content of additive material relatively,
High-density color record with clear print quality
Could be recorded in black.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. 1 and 2 are views showing one embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a carriage, and the carriage 1 is mounted on shafts 2 and 3 so as to be movable in the axial direction. On the carriage 1, four inkjet heads 4A to 4D for individually ejecting black, cyan, magenta, and yellow inks are mounted. By driving these inkjet heads 4A to 4D, color recording is performed on the recording paper 6 on the platen 5.

FIG. 2 shows the structure of the ink jet heads 4A to 4D. In FIG. 2, reference numeral 7 denotes a substrate of the inkjet heads 4A to 4D, and the substrate 7 is formed of stainless steel. 8 is an inkjet head 4A to 4D
The diaphragm 8 is also formed of stainless steel. Reference numeral 9 denotes a nozzle constituted by the substrate 7 and the vibration plate 8, and the nozzle 9 has a discharge port at a tip portion and ejects ink droplets.

Reference numeral 10 denotes a pressure chamber constituted by the substrate 7 and the vibration plate 8, and the pressure chamber 10 communicates with the nozzle 9.
Reference numeral 11 denotes a piezo element (pressure element) as pressure generating means. The piezo element 11 is provided on the diaphragm 8 outside the pressure chamber 10. The piezo element 11 generates pressure for ejecting ink from the nozzle 9.

Reference numeral 12 denotes a passage communicating with the pressure chamber 10.
The ink is supplied from the passage 12 to the pressure chamber 10. Passage 12
Are in communication with the ink chambers 13, respectively.
Has a supply port 14 communicating with the ink supply chamber. Next, the result of performing color recording using the ink jet printer will be described.

The composition of the ink used is as follows. Color (other than black) ink Hexylene glycol 10 wt% Glycerin 25 wt% Triethanolamine 2 wt% Water 61 wt% Dye 2 wt% Black ink Hexylene glycol 5 wt% Glycerin 30 wt% Triethanolamine 2 wt% Water 61 wt% Dye 2 wt% Included in color ink Hexylene glycol is 10wt%
On the other hand, the hexylene glycol contained in the black ink is 5 wt%, and the hexylene glycol content of the color ink is large. Hexylene glycol has the effect of dissolving the waterproofing agent of the recording paper 6, and the higher the content, the shorter the fixing time. As described above, the fixing time of the color ink is set to be shorter than the fixing time of the black ink, and the fixing time of the color ink is set to a predetermined time, for example, 1
It is set to 0 seconds or less.

The color ink and the black ink are used to drive the ink jet heads 4A to 4D to perform color recording on the recording paper 6. As a result, no color mixing occurs at the boundary between the colors. Therefore, high print quality could be obtained. In addition, as an inkjet printer,
Although the on-demand type is used in the present embodiment, the invention is not limited to this, and a continuous injection type or an electrostatic suction type may be used.

[0016]

As described above, according to the present invention, since the color ink penetrates and is fixed in about a few seconds, a clear boundary portion is formed because the liquid does not mix between the colors. In addition, a black ink having a longer fixing time than a color ink can achieve good print quality for both black and color recordings, such as recording of characters and the like used only in a single color, so that black recording with high density can be realized. be able to.

[Brief description of the drawings]

FIG. 1 is a diagram showing an inkjet printer according to an embodiment of the present invention.

FIG. 2 is a partial cross-sectional perspective view of an inkjet head.

FIG. 3 is an explanatory diagram showing a problem.

[Explanation of symbols]

 1: Carriage 2, 3: Shaft 4A-4D: Inkjet head 5: Platen 6: Recording paper 7: Substrate 8: Diaphragm 9: Nozzle 10: Pressure chamber 11: Piezo element 12: Passage 13: Ink chamber 14: Supply port

──────────────────────────────────────────────────続 き Continuation of front page (72) Inventor Osamu Taniguchi 4-1-1, Kamiodanaka, Nakahara-ku, Kawasaki-shi, Kanagawa Fujitsu Co., Ltd. (56) References JP-A-1-180883 (JP, A) JP-A-58-72461 (JP, A) JP-A-63-233881 (JP, A) JP-A-3-41171 (JP, A) JP-A-62-271778 (JP, A) (58) Fields investigated (Int) .Cl. ⁷ , DB name) C09D 11/00-11/20 B41J 2/01 B41M 5/00

Claims (2)

(57) [Claims] An ink jet head for separately ejecting a plurality of color inks and a black ink makes the black ink a single color ink.
In, the color inks overlap each other to get the desired color
In a color inkjet recording apparatus that performs recording on recording paper by that, at least the color ink, depending on the large content
Dissolve the waterproofing agent on the recording paper and apply the ink to the recording paper.
An additive material for shortening the contact time is contained, and the content of the additive material in the color ink is the same as that of the color.
The fixing time of the ink may be different between different colors on the recording paper.
And the amount of the additive material in the black ink is set to
Less than the content of the additive material in the color ink
Color ink dissolves the waterproofing agent on the recording paper.
An ink jet recording apparatus characterized in that the ink weakens the action of dissolving the waterproofing agent . 2. An ink-jet printer for ejecting ink individually.
Color ink jet recording on recording paper
Color inkjet recording ink used for recording device
A set that is used as a set to overlap with each other to obtain the desired color.
Number of color inks, and black ink used in a single color , at least in the color inks, depending on the amount of content
Dissolve the waterproofing agent on the recording paper and apply the ink to the recording paper.
An additive material for shortening the contact time is contained, and the content of the additive material in the color ink is the same as that of the color.
The fixing time of the ink may be different between different colors on the recording paper.
And the amount of the additive material in the black ink is set to
Less than the content of the additive material in the color ink
Color ink dissolves the waterproofing agent on the recording paper.
Is characterized by the fact that the ink has weakened the action of dissolving the waterproofing agent.
Color ink jet recording ink set.