CN111439032A

CN111439032A - Ink jet print head, ink jet printing apparatus, and ink jet printing method

Info

Publication number: CN111439032A
Application number: CN202010391150.5A
Authority: CN
Inventors: 谢永林; 王文浩
Original assignee: Suzhou Xinruifa Technology Co Ltd
Current assignee: Suzhou Xinruifa Technology Co Ltd
Priority date: 2020-05-13
Filing date: 2020-05-13
Publication date: 2020-07-24

Abstract

The present application provides an inkjet printhead comprising: at least two printing units, each of which is communicated with one color ink; the printing unit comprises a plurality of jet holes, the jet holes are arranged along a two-dimensional area, and the length of the two-dimensional area is greater than the width of the two-dimensional area; the printing units are arranged along the length direction. According to the ink-jet printing head, the ink-jet printing equipment and the ink-jet printing method, the printing units are arranged along the length direction, the color stacking sequence is the same in the back-and-forth printing process, the problem of color difference caused by different color stacking sequences is solved, and the printing quality is improved.

Description

Ink jet print head, ink jet printing apparatus, and ink jet printing method

Technical Field

The invention relates to the technical field of ink-jet printing, in particular to an ink-jet printing head, ink-jet printing equipment and an ink-jet printing method.

Background

In the ink jet printing technology, an ink jet printing head and a printing medium are relatively displaced, ink is ejected from an ejection hole of the ink jet printing head to form an ink droplet, and the ink droplet falls on the printing medium to form an image after passing through a space between the ink jet printing head and the printing medium, so that the printing work is completed.

Conventionally, in color printing, for example, as shown in fig. 1, a CMYK four-color print head is used to print a color pattern. The Yellow (Yellow) printing unit, the Cyan (Cyan) printing unit, the Magenta (Magenta) printing unit and the Black (Black) printing unit of the printing head are arranged along a first direction perpendicular to the length direction of the printing units, the arrangement direction of the Yellow (Cyan) printing unit, the Magenta (Magenta) printing unit and the Black (Black) printing unit is consistent with the movement direction of the printing head 1, and the printing head 1 scans back and forth along the

directions

12 and 13 and the printing medium 7 moves along the length direction of the printing units to complete the jet printing work so as to form characters or patterns with various colors; for example, when printhead 1 is in print zone 71, it is moved in direction 13 and the stacking sequence is Y-M-C-K, and after zone 71 is printed, print medium 7 is moved one step along print unit length direction 11, printhead 1 reverses its turn and moves in direction 12 and prints zone 72, the stacking sequence being K-C-M-Y, resulting in the stacking sequence of two adjacent zones being reversed. However, the difference in the color stacking sequence may cause color difference, for example, if a yellow ink drop lands on the printing medium first, a cyan ink drop is superimposed thereon, and then the cyan ink drop is superimposed thereon to generate a first green, if the cyan ink drop lands on the printing medium first, and then a yellow ink drop is superimposed thereon, a second green different from the first green may be generated, although both green colors exist, a certain color difference exists between the two green colors, and the printing quality is reduced.

Particularly for some special print media, for example: when the jet printing equipment is applied to printing of substrates such as hardboards, cloth and the like, solvent components in ink easily permeate the substrates, so that the colors of ink dots are changed, and the color superposition difference is more obvious in the process of superposing colors in different sequences; in addition, for some special printing fields, for example: when the pigment is used as ink and the adhesion capability of the pigment on cloth is poor, a color fixing agent needs to be coated on the cloth in advance, then the pigment ink is printed, and the influence of the color fixing agent on the color superposition aberration is more obvious.

In the prior art, some methods for solving the above problems are proposed, for example, japanese laid-open patent No. 11-320926 discloses that two sets of inkjet print heads can be used, and the arrangement order of the nozzles on the two sets of inkjet print heads is opposite, and the problem of color difference can be solved by using the second set of nozzles for printing during the return stroke, but as the number of the inkjet print heads increases, the cost of the inkjet system increases greatly; another method is a method disclosed in japanese laid-open patent No. 7-29423 which includes a solution to the problem of the color-difference of bi-directional printing by using unidirectional printing instead of bi-directional printing, but the printing speed is reduced and the printing efficiency is poor; in addition, the problem of chromatic aberration can be solved by increasing the number of printing passes (wherein a pass in the printing industry refers to the number of times that the printing head needs to pass through a certain area to complete printing of an image of the area, and only a part of ink dots of the image of the area are printed each time).

Disclosure of Invention

The present application provides an inkjet printhead comprising:

at least two printing units, each of which is communicated with one color ink;

the printing unit comprises a plurality of jet holes, the jet holes are arranged along a two-dimensional area, and the length of the two-dimensional area is greater than the width of the two-dimensional area;

the printing units are arranged along the length direction.

In one embodiment, the printing units are aligned along the length direction.

In one embodiment, the printing units are staggered along the length direction.

In one embodiment, adjacent printing units are closely connected along the length direction.

In one embodiment, there is a spacing between the adjacent printing units along the length direction.

In one embodiment, the number of printing units is 4, and black ink, cyan ink, magenta ink, and yellow ink are communicated, respectively.

In one embodiment, the number of printing units is 3, and cyan ink, magenta ink, and yellow ink are communicated, respectively.

In one embodiment, the orifices are aligned in at least one row along the length.

In one embodiment, the nozzles are arranged in at least two rows along the length direction, and the nozzles in two adjacent rows are staggered.

In one embodiment, the orifices are aligned in at least one row along a direction at an angle to the length direction.

Correspondingly, the application also provides an inkjet printing device, which comprises the inkjet printing head, a printing driving device for controlling the inkjet printing head to print on a printing medium, and a motion control device for controlling the inkjet printing head to move relative to the printing medium.

In one embodiment, the printer further comprises an image processing device which transmits image information to be printed into the print driving device.

Correspondingly, the present application also provides an inkjet printing method, which adopts the above inkjet printing apparatus, including:

the motion control device controls the ink jet printing head to move relative to the printing medium along a first direction perpendicular to the length direction;

the motion control device controls the printing medium to move along the length direction;

the printing driving device drives the ink-jet printing head to print on the printing medium when the ink-jet printing head and the printing medium move relatively.

In one embodiment, the inkjet printhead moves while printing on the print medium, and the print medium is stationary.

In one embodiment, the inkjet print head scans back along the first direction relative to the printing medium to print a partial area in the printing medium, and between two times of printing in the front and back adjacent partial areas, the inkjet print head turns around and stops printing, and the printing medium moves in steps along the length direction.

In one embodiment, the lengths of all the printing units of the at least two printing units along the length direction are the same, and the step length of the stepping movement of the printing medium along the length direction is 1/n of the length of each printing unit along the length direction, wherein n is more than or equal to 1, and the number of times that the ink jet printing head passes through the area when the partial area image is printed is completed.

In one embodiment, the motion control device drives the print head and the print medium to move relatively along the length direction, and drives the print medium to rotate around a rotation axis, wherein the rotation axis is parallel to the length direction; the print driving device controls the print head to print a pattern on the print medium.

In one embodiment, the print head moves in synchronization with the print medium.

In one embodiment, the relative movement distance between the printing head and the printing medium along the length direction is equal to e/k for each rotation of the printing medium, wherein e is the length of a two-dimensional area of the nozzle arrangement of one printing unit of the printing head, and k is a positive integer greater than or equal to 1

In one embodiment, the motion control device feeds back the relative position of the inkjet printhead and the print medium to the print driving device in real time.

According to the ink-jet printing head, the ink-jet printing equipment and the ink-jet printing method, the printing units are arranged along the length direction, and the color stacking sequence is the same in the bidirectional back-and-forth scanning printing process, so that the problem of color difference caused by different color stacking sequences is solved, and the printing quality is improved.

Drawings

FIG. 1 is a schematic diagram of a conventional inkjet printhead;

FIG. 2 is a schematic diagram of an exemplary embodiment of an inkjet printhead printing unit arrangement;

FIG. 3 is a schematic diagram of an exemplary embodiment of an inkjet printhead with printing units

FIG. 4 is a schematic diagram of an arrangement of orifices in a print order as set forth in one embodiment;

FIG. 5 is a schematic view of an inkjet printing apparatus according to an embodiment;

FIG. 6 is a schematic printing diagram of an inkjet printing apparatus according to an exemplary embodiment;

FIG. 7 is a schematic diagram of an embodiment of a proposed method of inkjet printing;

FIG. 8 is a schematic view of an ink jet printing method according to an embodiment;

fig. 9 is a schematic diagram of a printing apparatus proposed by an embodiment.

Detailed Description

In the description of this patent, it is noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience in describing the present invention and simplifying the description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus should not be construed as limiting the present invention; the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance; furthermore, unless expressly stated or limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, as they may be fixedly connected, detachably connected, or integrally connected, for example; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The meaning of the above terms in this patent may be specifically understood by those of ordinary skill in the art.

The inventor of the application invents a novel printing head, and the problem of color superposition and color difference during printing can be effectively solved under the conditions of not increasing additional nozzles and not reducing printing efficiency.

The present embodiment proposes an inkjet printhead including at least two printing units. Fig. 2 shows 7 arrangements, 2a-2b being aligned along

direction

11 and 2c-2g being staggered along direction 11. 2a, the inkjet printhead 1 comprises four printing units 20, which are arranged along the direction 11, with two adjacent printing units 20 being in close proximity without a gap. The length of the printing unit in the figure represents the length of the two-dimensional area of the arrangement of the spray orifices of the printing unit, and the width of the printing unit represents the width of the two-dimensional area of the arrangement of the spray orifices of the printing unit. 2b shows a case where there is a space between two adjacent printing units 20. 2c shows a case where the printing units 20 are partially arranged in a staggered manner along the direction 11, and two adjacent printing units 20 are closely connected without a space, and the two adjacent printing units 20 are partially overlapped when viewed from the direction 11. 2d also shows the case where the adjacent printing units 20 are arranged offset in the direction 11, and the adjacent two printing units 20 are spaced apart in the direction 11, and the adjacent two printing units 20 partially overlap when viewed from the direction 11. 2e shows the situation where two adjacent printing units 20 are completely staggered in the direction 11, and two adjacent printing units 20 are closely connected without a space. 2f shows the situation where two adjacent printing units 20 are completely offset from the direction 11, with a partial overlap between adjacent printing units 20 as seen in the direction 12. 2g shows a case where two adjacent printing units are completely staggered in the direction 11, and there is a space between two adjacent printing units 20, and there is no overlapping portion between the two adjacent printing units 20 as viewed in the direction 12.

Referring to fig. 3, taking the arrangement shown in fig. 2a as an example, three cases are shown, and as shown in fig. 3a, the inkjet printhead 1 includes four printing units, a first printing unit 21, a second printing unit 22, a third printing unit 23, and a fourth printing unit 24, which are arranged along the 11 direction, the first printing unit 21, the second printing unit 22, the third printing unit 23, and the fourth printing unit 24 communicate with C1, C2, C3, and C4 color inks, respectively, and the C1, C2, C3, and C4 may be any color. For example, the C1 is black ink, the C2 is cyan ink, the C3 is magenta ink, and the C4 is yellow ink. 3b shows a case where three printing units, namely, a first printing unit 21, a second printing unit 22 and a third printing unit 23 are included, the three printing units are arranged along the direction 11, the first printing unit 21, the second printing unit 22 and the third printing unit 23 are respectively communicated with inks of C1, C2 and C3, the C1, C2 and C3 can be any colors, for example, the C1 is magenta ink, the C2 is cyan ink and the C3 is yellow ink. Fig. 3C shows a case where two printing units, namely, a first printing unit 21 and a second printing unit 22, are included, the two printing units 10 are arranged along the direction 11, the first printing unit 21 and the second printing unit 22 are respectively communicated with C1 and C2 color inks, the C1 and C2 may be any color, for example, the C1 is magenta ink, and the C2 is black ink. The above three cases of printing units are taken as examples, and those skilled in the art can understand that other types of printing units are also applicable to the applied technical solution.

Referring to fig. 4, taking a first printing unit 21 as an example, the first printing unit 21 includes a plurality of nozzles 100, the nozzles 100 are arranged along a two-dimensional region 10, the two-dimensional region may be a region where the printing unit is located or a region slightly smaller than the printing unit, a length L of the two-dimensional region 100 is larger than a width W thereof, a length direction thereof is an 11 direction, and a width direction thereof is a 12 direction, as shown in fig. 4a, the printing unit 10 includes 6 nozzles 100 arranged in a row along the 11 direction, which are respectively labeled as a No. 1 hole, a No. 2 hole, a No. 3 hole, a No. 4 hole, a No. 5 hole and a No. 6 hole, the 6 nozzles are arranged in a row according to a label number, as shown in fig. 4b, the nozzles are arranged in a row, and the direction thereof has an angle with the 11 direction, as shown in fig. 4c, two rows of nozzles 100 in the two-dimensional region 10 are staggered, each row includes 4 nozzles, wherein the first row is labeled as a row, 12, 13 and 14, the second row is labeled as a row, the same as a row, and the second row is also shown in the same technical scheme, and the first application, the second row is also applicable to the first technical scheme, and the second application, wherein the second application, the first application, the second application, the same technical scheme is also includes four kinds of nozzles 14, and the same as the first application, the second application, and the second application, the first application, and the second application, and the same technical scheme.

According to the ink-jet printing head provided by the embodiment, the printing units are arranged along the length direction, and each printing unit ejects ink of one color, so that the overlapping sequence of the ink colors on a printing medium is consistent in the bidirectional scanning printing process, the problem of color difference caused by different overlapping sequences is solved, and the printing efficiency is improved while the printing speed is not reduced.

Correspondingly, the application also provides an ink jet printing device comprising the ink jet printing head of the embodiment, and the ink jet printing device can be used for small-sized scanners, medium-sized flat-plate machines, large-sized scanning and copying machines, large-sized jet printing machines, labeling machines, graphic and text printing machines, building material printing machines and the like.

As shown in fig. 5, the inkjet printing apparatus includes an inkjet printhead 1, a motion control device 3, and a print driving device 2, the print driving device 2 controls the inkjet printhead 1 to print on the print medium 7, and the motion control device 3 controls the inkjet printhead 1 to move relative to the print medium in a first direction perpendicular to the longitudinal direction and controls the print medium to move along the longitudinal direction. The ink jet printing apparatus further comprises image processing means 5, the image data source 4 providing image data signals to be printed, which image data signals are translated by the image processing means 5 into image information. The term "image" is meant herein to include any dot pattern specified by an image material. It may include graphical or textual images. It may also include various dot patterns suitable for printing functional devices or three-dimensional structures with suitable inks. The motion control device 3 feeds back the position of the inkjet printhead 1 and the position information of the printing medium 7 to the print driving device 2 in real time. The print driving device 2 sends an output signal to the electric pulse source 6 according to the image information provided by the image processing device 5, and the electric pulse source 6 sends an electric pulse waveform to the inkjet print head 1, so that the inkjet print head 1 ejects ink droplets. The print driving device 2 indicates when the inkjet print head starts printing and when the inkjet print head finishes printing according to the position of the inkjet print head 1 and the information of the print medium 7, and controls the inkjet print head 1 to print in a full range according to the pattern to be printed.

As shown in fig. 6, when the inkjet printing apparatus prints, the inkjet printhead 1 scans back and forth along the 12 direction to print multiple passes on the printing medium 7, and between the front and rear adjacent passes, the inkjet printhead 1 needs to turn around, at this time, the inkjet printhead 1 stops printing, the printing medium 7 moves along the 11 direction, and after the printing medium 7 has moved, the inkjet printhead 1 turns around to continue printing. The length (in the 11 direction) of the overlap of the print areas between the preceding and following adjacent passes determines the step length of the movement of the print medium 7 between the adjacent passes, which is 1/n of the length of the printing unit in the 11 direction, where n is the number of passes, n-1 is single-pass printing, and n >1 is multi-pass printing. The length of the printing unit is the distance between the two farthest nozzles in one printing unit along the 11 direction, for example, the distance between the nozzle No. 11 and the nozzle No. 24 in fig. 3c along the 11 direction.

Taking the example that the inkjet printing head 1 comprises four printing units and the printing units are respectively communicated with ink of KCMY, the inkjet printing head 1 moves along 12 directions in the printing process, the inkjet printing head 1 ejects black ink, cyan ink, magenta ink and yellow ink to a printing area in charge of each printing unit, and when the inkjet printing head 1 moves along the opposite direction of the 12 directions, the inkjet printing head also ejects black ink, cyan ink, magenta ink and yellow ink to the printing area in charge of each unit, and in the process of moving back and forth, the overlapping sequence of colors in each printing area is consistent, and color difference cannot be generated.

Fig. 7 shows a printing case when n is 1, and the moving step of the printing medium 30 is equal to the length of the printing unit in the direction 11. When the inkjet printing head 1 starts printing, the area 311 and 314 are within the printing range of the inkjet printing head 1, the printing head prints while moving along the direction 12, the area 311 is printed by black ink, the area 312 is printed by cyan ink, the area 313 is printed by magenta ink, and the area 314 is printed by yellow ink; the printing medium 30 moves by one step, the area 311 leaves the printing range, the area 315 enters the printing range, the inkjet printhead 1 moves in the opposite direction 13 of the printing range 12, the area 312 is printed by black ink, the area 313 is printed by cyan ink, the area 314 is printed by magenta ink, and the area 315 is printed by yellow ink; the print medium 30 continues to move one step, zone 312 leaves the print zone, zone 316 enters the print zone, zone 313 is printed with black ink, zone 314 is printed with cyan ink, zone 315 is printed with magenta ink, and zone 316 is printed with yellow ink; the print medium continues to move one step, zone 313 leaves the print zone, zone 317 enters the print zone, zone 314 is printed with black ink, zone 315 is printed with cyan ink, zone 316 is printed with magenta ink, and zone 317 is printed with yellow ink; to this end, the area 314 is printed with yellow, magenta, cyan and black inks in sequence to form the pattern to be formed in the area 314, and the subsequent areas 315 and 316 are printed with yellow, magenta, cyan and black inks in sequence to form the corresponding patterns, so that when the inkjet printhead 1 moves to the position shown in fig. 6, the area 317 is printed with yellow, magenta and cyan inks, i.e., black ink, the area 318 is printed with yellow and magenta inks, i.e., cyan ink, the area 319 is printed with yellow ink, i.e., magenta ink, and the area 320 is printed with yellow ink, i.e., yellow ink. The ink jet print head 1 prints on the print medium 30 in the above-described manner to form a desired pattern. The ink overlapping sequence of each area of the pattern is Y-C-M-K, so that the quality of the printed pattern is ensured.

Fig. 8 shows a printing situation when n is 2, and this embodiment differs from the embodiment shown in fig. 6 in that the moving step size of the printing medium 30 is equal to half the length of the printing unit in the 11 direction, which results in that one area needs to be printed twice with the same color. Starting from region 314b, each subsequent region is then printed with yellow, magenta, cyan and black inks to form a print pattern. The situation in which the ink jet print head 1 is printing the areas 316b-320a is shown in fig. 7, and the printing method is consistent with the embodiment shown in fig. 6, and will not be further elaborated herein. It will be appreciated by those skilled in the art that n can be any positive integer.

As shown in fig. 9, the motion control device 3 of the inkjet printing apparatus drives the print head 1 and the print medium 30 to move relatively along the length direction 11, and the motion control device 3 also drives the print medium 30 to rotate around a rotation axis G, which is parallel to the length direction 11; the print driving device (not shown in the drawings) controls the print head 1 to print a pattern on the print medium 30. The print head 1 and the print medium 30 move synchronously, and the relative movement distance between the print head 1 and the print medium 30 along the length direction 11 is equal to e/k for each rotation of the print medium 30, e is the length of one printing unit, and k is a pass number and is a positive integer greater than or equal to 1.

The above embodiments are merely illustrative of the technical ideas and features of the present invention, and the purpose thereof is to enable those skilled in the art to understand the contents of the present invention and implement the present invention, and not to limit the protection scope of the present invention. All equivalent changes and modifications made according to the spirit of the present invention should be covered within the protection scope of the present invention.

Claims

1. An inkjet printhead, comprising:

at least two printing units, each of which is communicated with ink of one color;

each printing unit comprises a plurality of jet holes, the jet holes are arranged along a two-dimensional area, and the length of the two-dimensional area is greater than the width of the two-dimensional area;

the printing units are arranged along the length direction.

2. The inkjet printhead of claim 1, wherein said printing units are aligned along said length direction.

3. The inkjet printhead of claim 1, wherein said printing units are staggered along said length direction.

4. An inkjet printhead according to claim 2 or 3, wherein adjacent printing units are closely connected along said length.

5. An inkjet printhead according to claim 2 or 3, wherein there is a space between adjacent printing units along the length direction.

6. The inkjet printhead of claim 1, wherein the number of printing units is 4 and black, cyan, magenta and yellow inks are communicated, respectively.

7. The inkjet printhead of claim 1, wherein the number of printing units is 3 and cyan, magenta and yellow inks are communicated, respectively.

8. The inkjet printhead of claim 1, wherein said orifices are arranged in at least one row along said length.

9. The inkjet printhead of claim 1, wherein said orifices are arranged in at least two rows along said length, adjacent rows being staggered.

10. The inkjet printhead of claim 1, wherein said orifices are aligned in at least one row along a direction at an angle to said length direction.

11. An inkjet printing apparatus comprising an inkjet printhead as claimed in any one of claims 1 to 10, print drive means for controlling the inkjet printhead to print on a print medium, and motion control means for controlling the relative motion of the inkjet printhead and the print medium.

12. Inkjet printing apparatus according to claim 12 further comprising image processing means for transmitting image information to be printed to said print driving means.

13. An inkjet printing method, characterized in that the inkjet printing apparatus according to any one of claims 11 to 12 is used, comprising:

14. The method of inkjet printing according to claim 13 wherein the inkjet printhead is moved while printing on the print medium and the print medium is stationary.

15. The method of inkjet printing according to claim 14 wherein the inkjet print head scans back along the first direction relative to the print medium to print a partial region of the print medium, the inkjet print head reversing and stopping printing between two prints of adjacent partial regions, and the print medium is moved stepwise along the length direction.

16. The inkjet printing method of claim 15, wherein the lengths of all printing units of the at least two printing units along the length direction are the same, and the step size of the step movement of the printing medium along the length direction is 1/n of the length of the two-dimensional area of each printing unit along the nozzle hole array, wherein n ≧ 1 is the number of times the inkjet printhead passes through the area when printing the partial area image is completed.

17. The method of inkjet printing according to claim 13 wherein a motion control device drives the printhead and the print medium relative to each other along the length direction and drives the print medium to rotate about a rotational axis, the rotational axis being parallel to the length direction;

the print driving device controls the print head to print a pattern on the print medium.

18. The method of inkjet printing according to claim 17 wherein the printhead moves in synchronization with the print medium.

19. The method of inkjet printing according to claim 18 wherein the distance of relative movement of the printhead and the print medium in the length direction per revolution of the print medium is equal to e/k, where e is the length of one print unit of the printhead and k is a positive integer greater than or equal to 1.

20. A method of inkjet printing according to claim 13 wherein the motion control means feeds back the relative position of the inkjet printhead and the print medium to the print drive means in real time.