NL2027440B1

NL2027440B1 - Page-wide Print Head Array and Printer Comprising said Page-wide Print Head Array

Info

Publication number: NL2027440B1
Application number: NL2027440A
Authority: NL
Inventors: H A Driessen Daniël
Original assignee: Canon Production Printing Holding Bv
Priority date: 2021-01-26
Filing date: 2021-01-26
Publication date: 2022-08-19

Abstract

The invention relates to a page-wide print head array comprising three print heads. The three print heads are positioned offset with respect to one another in the medium transport direction. The invention further relates to a printer comprising said page-wide 5 print head array.

Description

100098NLO1 1 Page-wide Print Head Array and Printer Comprising said Page-wide Print Head Array

FIELD OF THE INVENTION The invention relates to a page-wide print head array comprising three print heads. The invention further relates to a printer comprising said page-wide print head array.

BACKGROUND ART Printers are known in the art. A well-known type of printers are inkjet printers. This type of printer typically comprises one or more inkjet print heads configured to in operation eject ink onto a recording medium. The printers further comprise means for moving the recording medium with respect to the one or more print heads in a medium transport direction.

Inkjet printers may use either a single pass printing process or a scanning printing process. In a scanning process, the print head and the recording medium are moved with respect to one another in the medium transport direction and also in a scanning direction perpendicular to the medium transport direction. In a single pass process, during printing, the print heads and the recording medium are moved with respect to one another in the recording medium direction, but not in a direction perpendicular to the medium transport direction. In a single pass process, generally a page-wide print head array is used comprising one or more print heads. The page-wide print head array extends over at least the full width of a recording medium. Typically, page-wide print head arrays comprise two rows of print heads offset from one another in the medium transport direction.

All ink to be deposited on the recording medium by the page-wide array is deposited in one pass. Depending on the image to be printed, the print head array may need to deposit a large amount of ink. The ink may be supplied to the print head array via an ink supply system. Typically, such ink supply system may comprise an ink tank. In case large amounts of ink are requested at a time, the print heads in the print array may suffer a large under pressure, resulting in air being sucked into the print head. This phenomenon is also known as ink depletion. The occurrence of ink depletion is unwanted, as air in the print heads may case print artefacts to occur. Print artefacts may negatively influence the print quality of a printed image. When using a page-wide print head array having the print heads positioned in two rows offset in the medium transport

100098NLO1 2 direction, ink depletion is likely to occur when printing a full coverage plane. It is therefore an object of the invention to provide a page-wide array that is less sensitive to ink depletion.

SUMMARY OF THE INVENTION This object is achieved in a page-wide print head array comprising three print heads configured to in operation apply ink onto a recording medium that is moved with respect to the page-wide print head array in a medium transport direction, the page wide array extending in a first direction, the first direction being perpendicular to the medium transport direction, wherein a first one of the three print heads is positioned upstream in the medium transport direction with respect to a second one of the three print heads and wherein a third one of the three print heads is positioned downstream in the medium transport direction with respect to the second one of the three print heads.

The print head array is a mounting structure for mounting at least three print heads. The print head array may comprise fastening means for fastening the print heads in the print head array. In addition, the print head array may comprise adjustment means for adjusting the position of the print head in the print head array. The print head array may be configured to be positioned in a printer. When positioned in a printer, the print head array may be positioned such that in operation, the print heads may eject ink onto a recording medium, thereby forming an image onto the recording medium.

The print heads may be inkjet print heads. Inkjet print heads comprise a plurality of nozzles, through which ink may be expelled. Examples of inkjet print heads are thermal print heads or piezo electric print heads. Thermal print heads operate by locally heating the ink, thereby generating an increase in pressure in the print head, that results in ejection of a droplet. Piezo electric print heads comprise a piezo electric element that changes shape upon applying a voltage to the piezo electric element. The change in shape may result in the ejection of a droplet.

The print head array according to the present invention comprises at least three print heads. Optionally, the print head array may comprise more than three print heads. The print array may extend in a first direction, the first direction being essentially perpendicular to a direction of medium transport. The print heads may be divided over the print head array in the first direction. In that way, the entire width of a recording medium may be provided with ink by the print heads of the print head array. A first print

100098NLO1 3 head may be provided at an end portion of the print head array in the first direction. A second print head may be provided downstream in the first direction with respect to the first print head. A third print head may be provided downstream in the first direction with respect to the second print head.

The position of the different print heads in the print head array may further be shifted with respect to one another in the medium transport direction. The first print head is positioned upstream in the medium transport direction with respect to the second print head. The third print head is positioned upstream in the medium transport direction with respect to the second print head.

In this configuration, when a full coverage square is to be printed, the first, second and third print head start printing the full coverage square at a different moment in time, thereby reducing the risk of ink depletion compared to print head arrays according to the prior art.

In an embodiment, the print head array further comprises a fourth print head, wherein the fourth print head is positioned downstream in the medium transport direction with respect to the third one of the three print heads.

The more print heads are placed in a print head array, the more ink can be deposited and the longer the width of a recording medium that can be printed by the print head array. By positioning a fourth print head downstream in the medium transport direction with respect to the third one of the three print heads, the risk of ink depletion is reduced, also when using larger print head arrays.

In an embodiment, the print head array may comprise n print heads, n>3, wherein the n'" print head is positioned downstream in the medium transport direction with respect to the (n-1)! print head, and wherein the (n-1)! print head is positioned downstream in the medium transport direction with respect to the (n-2)" print head, etcetera.

Preferably, n may be in the range of 4 to 11, more preferably in the range of 5 to 7. In the embodiment, each print head that is positioned downstream of a first print head in the first direction and upstream of a second print head in the first direction is positioned upstream of said first print head in the medium transport direction and downstream of said second print head in the medium transport direction. Alternatively, each print head that is positioned downstream of a first print head in the first direction and upstream of a second print head in the first direction is positioned downstream of said first print head

100098NLO1 4 in the medium transport direction and upstream of said second print head in the medium transport direction. In an embodiment, the print head array may comprise at least two units of print heads, the atleast two units being adjacent to one another in the first direction, each unit comprising three print heads wherein a first one of the three print heads is positioned upstream in the medium transport direction with respect to a second one of the three print heads and wherein a third one of the three print heads is positioned downstream in the medium transport direction with respect to the second one of the three print heads.

In an embodiment, the first and second print head of the three print heads overlap in the first direction. The partial overlap between the first and second print heads may ensure that ink may be deposited over the full width of the recording medium, without leaving unprinted stripes.

In a further embodiment, the second and third print head of the three print heads overlap the first direction. The partial overlap between the second and third print heads may ensure that ink may be deposited over the full width of the recording medium, without leaving unprinted stripes.

In an embodiment, each one of the three print heads is configured to in operation eject droplets of an ink composition. The print heads may eject droplets onto the recording medium, thereby forming an image onto the recording medium.

In an aspect of the invention, a printer is provided, the printer comprising a page-wide print head array according to the present invention. Such printer may print image with improved print quality, because the occurrence of ink depletion is reduced.

In an embodiment, the printer comprises a plurality of page-wide print head arrays, wherein each one of the page-wide print head arrays is configured to eject in operation a specific type of ink. The printer may comprise a page-wide print head array configured to eject black ink. In

100098NLO1 addition, the printer may comprise a page-wide print head array configured to in operation eject cyan ink, a page-wide print head array configured to in operation eject magenta ink and a page-wide print head array configured to in operation eject yellow ink. Optionally, the printer may comprise a page-wide print head array configured to in 5 operation eject an overcoat composition. Optionally, the printer may comprise one or more further print head arrays configured to in operation eject further ink composition, such as, but not limited to an undercoat composition, metallic ink, red ink, green ink, orange ink, blue ink, light cyan ink, light magenta ink or grey ink. The printer according to this embodiment may be used to generate multi-color prints.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention will become more fully understood from the detailed description given herein below and accompanying schematical drawings which are given by way of illustration only and are not limitative of the invention, and wherein: Fig. 1 shows a schematic representation of an inkjet printing system. Fig. 2 shows a schematic representation of an page-wide printing array according to the prior art. Fig.3A shows a perspective view of a page-wide print head array according to a first embodiment of the invention. Fig. 3B shows a bottom view of a page-wide print head array according to a first embodiment of the invention. Fig. 4 shows a perspective view of a page-wide print head array according to a second embodiment of the invention. Fig. 5 shows a perspective view of a page-wide print head array according to a third embodiment of the invention. In the drawings, same reference numerals refer to same elements.

DETAILED DESCRIPTION An exemplary printing process in an ink-jet printing apparatus of the present invention will now be described with reference to the appended drawings shown in Fig. 1 and Fig.

100098NLO1 6

2. Figs. 1 and 2 show schematic representations of an inkjet printing system and an inkjet print head array, respectively. The print head array shown in Fig. 2 is a print head array according to the prior art. However, the present ink-jet printing process and ink-jet printing apparatus are not limited to this exemplary embodiment.

Fig. 1 shows a printer. A printer is also known as an inkjet printing system or an inkjet marking device. Fig. 1 shows that a sheet of a recording medium P is transported in a direction for conveyance as indicated by arrows 50 and 51 and with the aid of transportation mechanism 12. The transportation mechanism 12 drives a conveyor belt

21. The conveyor belt 21 may carry a sheet of recording medium, thereby transporting the sheet through the various parts of the printer. A recording medium may also be referred to as receiving medium or print medium. In the embodiment shown in Fig. 1, the recording medium P is a sheet. Alternatively, the recording medium may be a web. Transportation mechanism 12 may be a driven belt system comprising one (as shown in Fig. 1) or more belts. Alternatively, one or more of these belts may be exchanged for one or more drums. A transportation mechanism may be suitably configured depending on the requirements (e.g. sheet registration accuracy) of the sheet transportation in each step of the printing process and may hence comprise one or more driven belts and/or one or more drums. For a proper conveyance of the sheets of receiving medium, the sheets need to be fixed to the transportation mechanism. The way of fixation is not particularly limited and may be selected from electrostatic fixation, mechanical fixation (e.g. clamping) and vacuum fixation. Of these vacuum fixation is preferred. The printing process as described below comprises the following steps: media pre- treatment, image formation, drying and fixing and optionally post treatment. Media pre-treatment To improve the spreading and pinning (i.e. fixation of pigments and water-dispersed polymer particles) of the ink on the recording medium, in particular on slow absorbing media, such as machine coated media, the recording medium may be pre-treated, i.e. treated prior to printing an image on the medium. The pre-treatment step may comprise the application of the pre-treatment liquid of the present invention and may further comprise one or more of the following: — preheating of the receiving medium to enhance spreading of the used ink on the

100098NLO1 7 receiving medium and/or to enhance absorption of the used ink into the receiving medium; — corona or plasma treatment. In an alternative embodiment, the printer may not comprise a pre-treatment unit.

Primer pre-treatment Any conventionally known method can be used to apply the pre-treatment liquid. In the embodiment shown in Fig. 1, a roller coating (14) is used. Alternative examples of an application way include: an ink-jet application, a curtain coating and a spray coating.

There is no specific restriction in the number of times with which the pre-treatment liquid is applied. It may be applied in one time, or it may be applied in two times or more. Application in two times or more may be preferable, since cockling of the coated printing paper can be prevented and the film formed by the surface pre-treatment liquid will produce a uniform dry surface having no wrinkle by applying in 2 steps or more.

As an application area of the pre-treatment liquid, it may be possible to apply only to the printed portion, or to the entire surface of both the printed portion and the non-printed portion. The pre-treatment liquid may be an aqueous pre-treatment liquid.

Corona or plasma treatment Corona or plasma treatment may be used as a pre-treatment step by exposing a sheet of a recording medium to corona discharge or plasma treatment. In particular when used on media like polyethylene (PE) films, polypropylene (PP) films, polyetyleneterephtalate (PET) films and machine coated media, the adhesion and spreading of the ink can be improved by increasing the surface energy of the media.

With machine coated media, the absorption of water can be promoted which may induce faster fixation of the image and less puddling on the receiving medium. Surface properties of the receiving medium may be tuned by using different gases or gas mixtures as medium in the corona or plasma treatment. Examples are air, oxygen, nitrogen, carbondioxide, methane, fluorine gas, argon, neon and mixtures thereof.

Corona treatment in air is most preferred.

Fig. 1 shows that the sheet of receiving medium P may be conveyed to and passed through a first pre-treatment module 13, which module may comprise a preheater, for example a radiation heater, a corona/plasma treatment unit, a gaseous acid treatment

100098NLO1 8 unit or a combination of any of the above. Subsequently, a predetermined quantity of the present pre-treatment liquid is applied on the surface of the receiving medium P at pre-treatment liquid applying member 14. Specifically, the pre-treatment liquid is provided from storage tank 15 of the pre-treatment liquid to the pre-treatment liquid applying member 14 composed of double rolls 16 and 17. Each surface of the double rolls may be covered with a porous resin material such as sponge. After providing the pre-treatment liquid to auxiliary roll 16 first, the pre-treatment liquid is transferred to main roll 17, and a predetermined quantity is applied on the surface of the recording medium P. Alternatively, the pre-treatment liquid can also be applied by one or more print heads. Subsequently, the coated printing paper P on which the pre-treatment liquid was supplied may optionally be heated and dried by drying member 18 which is composed of a drying heater installed at the downstream position of the pre-treatment liquid applying member 14 in order to decrease the quantity of the water content in the pre- treatment liquid to a predetermined range.

To prevent the transportation mechanism 12 being contaminated with pre-treatment liquid, a cleaning unit (not shown) may be installed and/or the transportation mechanism may be comprised of multiple belts or drums as described above. The latter measure prevents contamination of the upstream parts of the transportation mechanism, in particular of the transportation mechanism in the printing region. Image formation Image formation is performed in such a manner that, employing an inkjet printer loaded with inkjet inks, ink droplets are ejected from the inkjet heads based on the digital signals onto a recording medium. Although both single pass inkjet printing and multi pass (i.e. scanning) inkjet printing may be used for image formation, single pass inkjet printing is preferably used since it is effective to perform high-speed printing. Single pass inkjet printing is an inkjet recording method with which ink droplets are deposited onto the receiving medium to form all pixels of the image by a single passage of a recording medium underneath an inkjet marking module. In Fig. 1, 11 represents an inkjet marking module comprising four page-wide print head

100098NLO1 9 arrays, indicated with 111, 112, 113 and 114, each arranged to eject an ink of a different color (e.g. Cyan, Magenta, Yellow and blacK). A page-wide print head array for use in single pass inkjet printing, 111, 112, 113, 114, has a length of at least the width of the desired printing range, the printing range being perpendicular to the medium transport direction, indicated with arrows 50 and 51. The inkjet page-wide print head array be constructed by combining three or more inkjet heads, such that the combined lengths of the individual inkjet heads cover the entire width of the printing range. Such a constructed page-wide print head array (PWA) is also termed an inkjet marking device. Fig. 2 shows an page-wide print head array according to the prior art, comprising 7 individual inkjet heads (201, 202, 203, 204, 205, 206, 207) which are arranged in two parallel rows, a first row comprising four inkjet heads (201 - 204) and a second row comprising three inkjet heads (205 - 207) which are arranged in a staggered configuration with respect to the inkjet heads of the first row. In image formation by ejecting an ink, an inkjet head (i.e. printhead) employed may be either an on-demand type or a continuous type inkjet head. As an ink ejection system, there may be usable either the electric-mechanical conversion system {e.g., a single- cavity type, a double-cavity type, a bender type, a piston type, a shear mode type, or a shared wall type), or an electric-thermal conversion system (e.g., a thermal inkjet type, or a Bubble Jet type (registered trade name)). Among them, it is preferable to use a piezo type inkjet recording head which has nozzles of a diameter of 30 um or less in the current image forming method.

Fig. 1 shows that after pre-treatment, the receiving medium P is conveyed to upstream part of the inkjet marking module 11. Then, image formation is carried out by each color ink ejecting from each page-wide print head arrays 111, 112, 113 and 114 arranged so that the whole width of the receiving medium P is covered.

Optionally, the image formation may be carried out while the recording medium is temperature controlled. For this purpose a temperature control device 19 may be arranged to control the temperature of the surface of the transportation mechanism (e.g. belt or drum} underneath the inkjet marking module 11. The temperature control device

100098NLO1 10 19 may be used to control the surface temperature of the recording medium P, for example in the range of 30°C to 60°C.

The temperature control device 19 may comprise heaters, such as radiation heaters, and a cooling means, for example a cold blast, in order to control the surface temperature of the receiving medium within said range.

Subsequently and while printing, the receiving medium P is conveyed to the downstream part of the inkjet marking module 11. Drying and fixing After an image has been formed on the receiving medium, the prints have to be dried and the image has to be fixed onto the receiving medium.

Drying comprises the evaporation of solvents, in particular those solvents that have poor absorption characteristics with respect to the selected recording medium.

Fig. 1 schematically shows a drying and fixing unit 20, which may comprise a heater, for example a radiation heater.

After an image has been formed, the print is conveyed to and passed through the drying and fixing unit 20. The print is heated such that solvents present in the printed image, to a large extent water, evaporate.

The speed of evaporation and hence drying may be enhanced by increasing the air refresh rate in the drying and fixing unit 20. Simultaneously, film formation of the ink occurs, because the prints are heated to a temperature above the minimum film formation temperature (MFT). The residence time of the print in the drying and fixing unit 20 and the temperature at which the drying and fixing unit 20 operates are optimized, such that when the print leaves the drying and fixing unit 20 a dry and robust print has been obtained.

As described above, the transportation mechanism 12 in the fixing and drying unit 20 may be separated from the transportation mechanism of the pre-treatment and printing section of the printing apparatus and may comprise a belt or a drum.

Hitherto, the printing process was described such that the image formation step was performed in-line with the pre-treatment step (at least application of an (aqueous) pre- treatment liquid) and a drying and fixing step, all performed by the same apparatus (see Fig. 1). However, the printing process is not restricted to the above-mentioned embodiment.

A method in which two or more machines are connected through a belt conveyor, drum conveyor or a roller, and the step of applying a pre-treatment liquid, the (optional) step of drying a coating solution, the step of ejecting an inkjet ink to form an

100098NLO1 11 image, and the step or drying an fixing the printed image are performed. It is, however, preferable to carry out image formation with the above defined in-line image forming method.

Fig.3A and 3B show a page-wide print head array 220 according to a first embodiment of the present invention. Fig. 3A shows a perspective view, whereas Fig. 3B shows a bottom view.

The page-wide print head array 220 comprises a housing 111, schematically depicted in Fig. 3A as a dotted bar. The page-wide print head array may further comprise means for attaching the page-wide print head array to a printer frame (not shown). The page-wide print head array may further comprise means for adjusting the position of the page-wide print head array with respect to the printer frame (not shown). The page-wide print head array 220 further comprises a first print head 210, a second print head 211 and a third print head 212. The print head array 220 has a length L extending in the first direction 52, the first direction 52 being perpendicular to medium transport direction 51. The first print head 210 is positioned upstream in the medium transport direction 51 with respect to the second print head 211. The third print head 212 is positioned downstream with respect to the second print head 211. Fig. 3B shows a bottom view of the page-wide print head array 220 according the a first embodiment of the present invention. Each one of the print heads 210, 211, 212 has a nozzle surface 9 which in operation is directed towards the conveyor belt (not shown in Fig. 3B) carrying the recording medium. In the nozzle surface 9, a number of nozzles 8 are positioned. In Fig. 3B 9 nozzles 8 are depicted, but in practice, the nozzle surface 9 may comprise many more nozzles, for examples hundreds of nozzles. Nozzles 8 are also referred to as orifices. Ink may be ejected through the nozzles 8 upon actuation of the print head. An open space is provided in the housing 111 of the page-wide array to allow ink ejected through the nozzles 8 to land on a sheet of recording medium. The first print head 210 and the second print head 211 overlap in a direction perpendicular to the medium transport direction 51. Also the second print head 211 and the third print head 212 overlap in a direction perpendicular to the medium transport direction 51. The overlap between the second print head 211 and the third print head 212 is indicated by reference number 70 in Fig. 3B. Fig. 4 shows a perspective view of a page-wide print head array 220 according to a

100098NLO1 12 second embodiment of the invention. The page-wide print head array 220 comprises a housing 111, schematically depicted in Fig. 4 as a dotted bar. The page-wide print head array 220 may further comprise means for attaching the page-wide print head array to a printer frame (not shown). The page-wide print head array may further comprise means for adjusting the position of the page-wide print head array with respect to the printer frame (not shown). The page-wide print head array 220 further comprises a first print head 210, a second print head 211, a third print head 212 and a fourth print head 213. The print head array 220 has a length L extending in the first direction 52, the first direction 52 being perpendicular to medium transport direction 51. The first print head 210 is positioned upstream in the medium transport direction 51 with respect to the second print head 211. The third print head 212 is positioned downstream in the medium transport direction 51 with respect to the second print head 211. The fourth print head 213 is positioned downstream in the medium transport direction 51 with respect to the third print head 212.

Fig. 5 shows a perspective view of a page-wide print head array 220 according to a third embodiment of the invention. The page-wide print head array 220 comprises a housing 111, schematically depicted in Fig. 5 as a dotted bar. The page-wide print head array may further comprise means for attaching the page-wide print head array to a printer frame (not shown). The page-wide print head array may further comprise means for adjusting the position of the page-wide print head array with respect to the printer frame (not shown). The print head array 220 has a length L extending in the first direction 52, the first direction 52 being perpendicular to medium transport direction 51.

The page-wide print head array 220 further comprises a first print head 210, a second print head 211, a third print head 212, a fourth print head 213, a fifth print head 214, a sixth print head 215 and a seventh print head 216. The first print head 210, the second print head 211and the third print head 212 together form a first unit of print heads. The fourth print head 213, the fifth print head 214 and the sixth print head 215 together form a second unit of print heads.

Inthe first unit of print heads, the first print head 210 is positioned upstream in the medium transport direction 51 with respect to the second print head 211 and the third print head 212 is positioned downstream in the medium transport direction 51 with respect to the second print head 211.

In the second unit of print heads, the fourth print head 213 is positioned upstream in the

100098NLO1 13 medium transport direction 51 with respect to the fifth print head 214 and the sixth print head 216 is positioned downstream in the medium transport direction 51 with respect to the fifth print head 214. The seventh print head 216 is positioned upstream in the medium transport direction 51 with respect to the fifth print head 214 and the sixth print head 215. The seventh print head 216 is positioned in the same position in the recording medium direction 51 as the first print head 210 and the fourth print head 213. However, the seventh print head 216 is positioned offset from the first print head 210 and the fourth print head 213 in the first direction 52.

Detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention, which can be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present invention in virtually and appropriately detailed structure. In particular, features presented and described in separate dependent claims may be applied in combination and any combination of such claims are herewith disclosed.

Further, the terms and phrases used herein are not intended to be limiting; but rather, to provide an understandable description of the invention. The terms “a” or “an”, as used herein, are defined as one or more than one. The term plurality, as used herein, is defined as two or more than two. The term another, as used herein, is defined as at least a second or more. The terms including and/or having, as used herein, are defined as comprising (i.e., open language).

100098NLO1 14 Embodiments

1. Page-wide print head array (111) comprising three print heads (210, 211, 212) configured to in operation apply ink onto a recording medium (P) that is moved with respect to the page-wide print head array (111) in a medium transport direction (51), the page wide print head array (111) extending in a first direction (52), the first direction (52) being perpendicular to the medium transport direction (51), wherein a first one (210) of the three print heads (210, 211, 212) is positioned upstream in the medium transport direction (51) with respect to a second one (211) of the three print heads (210, 211, 212) and wherein a third one (212) of the three print heads (210, 211, 212) is positioned downstream in the medium transport direction (51) with respect to the second one (211) of the three print heads (210, 211, 212).

2. Page-wide print head array (111) according to embodiment 1, wherein the print head array (111) further comprises a fourth print head (213), wherein the fourth print head (213) is positioned downstream in the medium transport direction (51) with respect to the third one (212) of the three print heads.

3. Page-wide print head array (111) according to embodiment 1, wherein the first (210) and second (211) print head of the three print heads overlap in the first direction (52).

4. Page-wide print head array (111) according to embodiment 3, wherein the second (211) and third print head (212) of the three print heads overlap in the first direction (52).

5. Page-wide print head array (111) according to any one of the preceding embodiments, wherein each one of the three print heads (210, 211, 212) is configured to in operation eject droplets of an ink composition.

6. Printer comprising a page-wide print head array (111) according to any of the embodiments 1-5.

7. Printer according to embodiment 6, wherein the printer comprises a plurality of page-wide print head arrays (111, 112, 113, 114) , wherein each one of the page-wide print head arrays (111, 112, 113, 114) is configured to eject in operation a specific type of ink.

Claims

100098NLO1 15 Conclusions

A page-wide printhead array (111) comprising three printheads (210, 211, 212) configured to operatively apply ink to a receiving medium (P), which receiving medium (P) is moved relative to the pagewide printhead array (111) in a media transport direction (51), the page-wide printhead array (111) extending in a first direction (52), the first direction (52) being perpendicular to the media transport direction (51), a first (210) of the three printheads ( 210, 211, 212) is upstream in the media transport direction (51) with respect to a second (211) of the three print heads (210, 211, 212) and wherein a third (212) of the three print heads (210, 211, 212) is downstream in the media transport direction (51) relative to the second (211) of the three print heads (210, 211, 212).

The page-wide printhead array (111) of claim 1, wherein the printhead array (111) further comprises a fourth printhead (213), the fourth printhead (213) being downstream in the media transport direction (51) relative to the third (212) of the three print heads.

The page-wide printhead array (111) of claim 1, wherein the first (210) and the second (211) printheads of the three printheads overlap in the first direction (52).

The page-wide printhead array (111) of claim 3, wherein the second (211) and third printheads (212} of the three printheads overlap in the first direction (52).

The page-wide printhead array (111) of any preceding claim, wherein each of the three printheads (210, 211, 212) is configured to eject droplets of an ink composition in operation.

A printer comprising a page-wide printhead array (111) according to any one of claims 1-5.

The printer of claim 6, wherein the printer comprises a plurality of page-wide printhead arrays (111, 112, 113, 114), wherein each of the page-wide printhead arrays (111, 112, 113, 114) is configured to actuate drops of a specific type of ink composition.