CA2023022A1 - Multi-color ink jet printing process and color pen for minimizing banding and color bleed and ink jet nozzle plate for use therewith - Google Patents
Multi-color ink jet printing process and color pen for minimizing banding and color bleed and ink jet nozzle plate for use therewithInfo
- Publication number
- CA2023022A1 CA2023022A1 CA 2023022 CA2023022A CA2023022A1 CA 2023022 A1 CA2023022 A1 CA 2023022A1 CA 2023022 CA2023022 CA 2023022 CA 2023022 A CA2023022 A CA 2023022A CA 2023022 A1 CA2023022 A1 CA 2023022A1
- Authority
- CA
- Canada
- Prior art keywords
- color
- nozzles
- ink
- ink jet
- columns
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
- B41J—TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
- B41J2/00—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
- B41J2/005—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by bringing liquid or particles selectively into contact with a printing material
- B41J2/01—Ink jet
- B41J2/21—Ink jet for multi-colour printing
- B41J2/2132—Print quality control characterised by dot disposition, e.g. for reducing white stripes or banding
Abstract
Abstract A process for multi-color ink jet printing and a color pen and nozzle plate for use therewith wherein nozzles are provided in adjacent spaced apart and vertically offset columns in the nozzle plate. Each column of nozzles is dedicated to a particular color of ink to be printed, and these columns of nozzles are passed in multiple, back and forth passes across a print medium during an ink jet printing process. Using this process, the rate of ink deposition per printhead pass across a print media will be minimized, and this enhances color uniformity and absorption by the print media, particularly in applications requiring large amounts of solid color area fill. In addition, the formation of horizontal and vertical color boundaries are inherently separated spatially and in time, and are limited to a maximum of two dot rows of drying ink dots after each pass. This approach thus minimizes color mixing and color bleed at the color boundaries without any sacrifice in print speed relative to known prior art processes.
Description
2~22 MULTI-CQLOR INK JET PRINTlNG PROCESS AND COLOR PEN
FOR MINIMIZING B~NDING AND cOLOR BLEED AND
INK JET NOZZLE PLATE FOR USE THEREWITH
Technical Field This invention relates generally to ink jet printing and more particularly to an improved multi-color dot-next-to-dot (DND) ink jet printing process for reducing bandiny and color bleed on printed media. This process serves to improve the overall ink jet print quality on the printed media.
Background_Art Substantial advances have been made in recent years in the field of color ink jet printing, and many of these advances relate to improving the print quality of the printed media, which include plain paper, special papers and various types of transparencies. Typical of these advancements in this art and technology are the various improvements and developments embodied in the Hewlett Packard "PAINTJET"
printer first marketed in August 1987. These are described in some detail in the Hewlett Packard Journal, Volume 39, No. 4, August 1988, incorporated~herein by reference.
In the field of multi-color ink jet printing, it is known to construct ink jet pens (also referred to as printheads) having nozzle or orifice groups of primary colors which are spaced adjacent to one another aiong a length dimension of the printhead and usually perpendicular to printhead motion. When the printhead is moved from side-to-side relative to an adjacent print medium, each color-dedicated nozzle group is fired simultaneously to produce a combined swath width having a total nu~ber of adjacent dot rows equal to the sum of the total numbe~ of nozzles in all of the nozzle groups. For example, in the three color thermal ink jet pen disclosed in U. S. Patent No. 4,812,859 issued to C. S. Chan et al, the three primary color nozzle groups of cyan, yellow, and magenta have sixteen nozzles in each group.
Thus, three separate adjacent color bands totalling forty-Case 187353 ~ -~` 2 ~ 2 2 eight ver~ical dot rows may be produced when the pen is scanned from side-to-side across a print medium moving relative thereto. U. S. Patent No. 4,812,859 issued to C. S.
Chan et al is assigned to the present assignee and is S incorporated herein by re~erence.
Whereas the above identified thermal ink jet color pen disclosed in U. S. Patent No. 4,812,859 performs quite satisfactorily in most respects, there are nevertheless certain ink jet printing applications where the above Chan et al patented approach to multi-color printing may produce either banding or an undesirable color bleed or color mixing.
A11 of these undesirable characteristics in print quality may result from an insufficient drying of ink printed over a given surface area of print media. Thus, this insufficient drying of ink may produce banding in areas of solid color fill where the excessive printed ink volume deposited per unit area per ~ unit of time produces an uneven drying of ink across the width `~ of a printed swath. The ink will bead up at a small angle and in a smoothly rounded curvature across the width of the printed swath, and as a result of this phenomenon the ink at the swath edges will dry faster than the ink in the interior regions of the swath. This produces a lighter color at the swath edges, and this lighter color may be visible as a narrow lighter band extending horizontally across the swath. Hence, the term "banding" has been used in the ink jet printing arts to describe this undesirable characteristic in print quality.
In yet other printing applications, this same excess f ink volume per 4nit of,printed area per unit of time ! may produce an undesirable color bleed or color mixing where different colors are printed in direct side-by-side contact to establish a two-color interface. If these two colors are printed either simultaneously or in sufficiently rapid succession, the wet ink at the two-color interface boundary will bleed laterally across this-boundary and mix with the ~5 other different colored ink which may not be completely dried.
Case 187353 2~2~22 ,, .
This interaction will in turn produce an undesirable visual blurring at the two color interface boundary.
Both of the above problems of banding and color bleed are caused by the side-by-side swath printing over adjacent printed areas of print media with more ink volume per unit area per unit of time than will permit a sufficient and uniform drying of the ink. The print media, such as untreated plain paper, simply cannot sufficiently absorb the ink printed above a given printing speed in the swath area whose width is defined by a number of simultaneously printed adjacent dot rows, such as the sixteen (16) dot rows per swath arranged in the nozzle geometry of the adjacent color printheads in U. S.
Patent No. 4,812,859 identified above.
Disclosure of Invention ~; 15 A general object of this invention is to provide a novel alternative approach to multi-color ink jet printing and one operable in contrast to the -simultaneous printing of adjacent swaths of different colors as described above. This novel approach is useful to either minimize or eliminate the above undesirable print characteristics of banding, color mixing and color bleed. This is accomplished in accordance with the present invention by printing selected dot rows of ink horizontally across a predefined print area and in succession by ink ejected from separate, vertically offset 25 nozzle columns in an ink jet pen or printhead. These selected ~ ~5 dot rows may be printed either simultaneously or in rapid succession, ~or both/ ~ntil all of the nozzles necessary to print a desired image or a solid area flll in the predefined area have be~en fired. The above nozzle firing sequence is such that never more than two adjacent dot rows are printed within the time it takes the nozzle plate to make one traverse or pass across one dimension of the predefined print area of the printed media.
In a preferred embodiment of thè invention, the above process employs a novel nozzle plate geometry wherein a Case 187353 ~2~ 2 , \
plurality of color-dedicated nozzle columns extend vertically along one dimension of the nozzle plate and perpendicular to the direction of nozzle plate horizontal motion described above. Each nozzle column is declicated only to one color of ink such as the primary ink colors of cyan, yello~, magenta or black, and the nozzles in each column are offset or staggered vertically with respect to nozzles in each adjacent column by a distance equal to one dot row. Thus, the selective firing of these nozzles during a horizontal traverse or pass across a print medium is always such that never more than two vertically spaced adjacent dot rows are deposited either simultaneously or in rapid succession. This operation continues as the nozzle plate completes all of its multiple passes over a single print area necessary to print a desired image or solid area fill over the above predefined area. The vertical dimension of this predefined area is substantially coextensive with the vertical dimension of the nozzle plate.
Another object of this invention is to provide a new ;
and improved color printing process of the type described which minimizes banding and color bleed without any sacrifice in printing speed.
Another object of this invention is to provide a new and improved process for ink jet color printing which improves ink drying uniformity over a given printed area and thereby improves the overall print quality of color images ~hich are printed within that area.
Another object is to provide a ne-~ and improved process of the type described which is particularly useful for lmprov1ng color print quality on less-absorbent types of print media having a low drying factor, such as certain grades of office papers and transparencies. -~
A feature of this invention is the provision of a multi-color inX jet printing process of the type described wherein full speed, multiple pass pri-nting is utilized to achieve an increased average drying time between different color dots printed adjacent to one another on a print medium.
Case 187353 ~" 2 ~ 2 .;
;
Another feature o~ this invention is the provision of a novel nozzle plate geometry for use in a multi-color ink jet pen, including spaced apart columns of color-dedicated nozzles therein. The nozzles in each column are vertically offset with respect to nozzles in adjacent columns by a predetermined distance equal to one dot row, and means are provided for fluidically coupling separate colors of ink to each of the columns of nozzles, respectively.
Another feature of this invention is the provision of a new and improved process of the type described which produces a horizontal ink drying boundary between only two solid filled printed rows, so that the total drying area never exceeds an allowable maximum of two dot rows in total width. -;Another feature of this invention is the provision of a color ink jet pen for generating graphic color pixels which are interlaced at the dot row level. This minimizes the visible effects of scan line errors on the printed medium.
Another feature of this invention is the provision of ~`an improved nozzle plate geometry which is operative in combination with currently available print algorithms for the purpose of reduci~g color bleed.
The above objects, features and various related advantages of this invention will become better understood with reference to the following description of the ;~ 25 accompanying drawings.
Brief Description of the Drawinqs ~j Figure 1 is an isom~etric view of a multi-color ink!jet pen having an ink ejection orifice plate whose nozzle arrangement is configured in accordance with the present invention.
Figure 2 is an enlarged plan view of the orifice plate of Figure 1.
Figures 3A through 3D are schematic plan views illustrating the nozzle firing sequence used on four 35 successive passes of the orifice plate over a given print ;~
.:
Case 187353 ?,02~û22 area. These successive passes are used to form adjacent upper and lower solid fill areas of cyan, C, and magenta, M, and these solid fill areas define a single horizontal cyan/magenta interface boundary.
Figures 4A through 4D are schematic plan views illustrating the nozzle fixing sequence used on four successive passes of the orifice plate over a given print area to form solid fill areas of cyan, C, magenta, M, yellow, Y, and black, K, as shown in Figure 4D. These C, M, Y, and K
solid fill areas are separated in Figure 4D by both vertical and horizontal interface boundaries located between the solid fill areas as shown.
Descri~tion of the Preferred Embo~iment ~ ;
Referring now to Figure 1, there is shown a three-color and black ink jet pen which is generally designated as 10 and includes an orifice or nozzle plate 12 which is secured to an~
adjacent barrier layer 14. The ~arrier layer 14 is typically formed of a polymer material such as the well-known insulator VACREL and is secured to a thin film resistor (TFR) substrate 16 whose general construction and architecture are well-known in the art. In the field of thermal ink jet printing, these thin film resistor substrates 16 may be constructed to have photolithographically defined heater resistors (not shown) which are aligned with ink ejection openings in the orifice -; 25 plate 12, and such construction is described in more detail in the above identified He~lett Packard Journal, Volume 39, No. 4, August 1988; inlthe Hewlett PacXard Journal, Volume 36,`
No. S, ~ay 1985, and also in the above identified U. S. Patent No. 4,812,859 issued to C. S. Chan et al. These ink ejection openings are referred to alternatively in this field of ink jet printing as either "orifices" or "nozæles".
The TFR substrate 16 is in turn mounted on one surface of a pen body housing 18 having separate ink storage compartments 20, 22, 24, and 26 therein containing, respectively, the primary ink colors of cyan, magenta, yellow, Case 187353 2 ~ 2 .
and black. This ink storage may be accomplished using a polyurethane foam material in the compartments 20, 22, 24, and 26, and processes used for foam storage in this type of pen body housing construction are disclosed, for example, in U. S.
Patent No. 4,771,295 issued to Jeffrey P. Baker et al, assigned to the present assignee and incorporated herein by reference.
The orifice plate 12 of Figure 1, also shown in the enlarged plan view of Figure 2, includes ~our columns of nozzles 30, 32, 34, and 36 which are fluidically isolated one from another and fed, respectively, with the four primary ink colors of cyan, magenta, yellow, and black as indicated in these figures. Each of these nozzle columns is separated from an adjacent column by a width dimension 'W as indicated in Figure 2 and is offset vertically from'an adjacent nozzle position by a length dimension D. Thus, the center-to-center spacing between adjacent nozzles of like color in any of th~
nozzle columns 30, 32, 34, and 36 is a dimension of four (4) times the number of nozzle columns, or 4D as indicated in Figure 2. Using a print density of 300 dots per inch (DPI), the dimension D will be approximately 0.0033 inches (1/300"), and W will range typically from 25D to 32D.
Referring now in succession to Figures 3A through 3D, the orifice plate or nozzle plate 12 is first moved as shown in Figure 3A from a firs. or starting position 4~ on the right hand side of the fi~ure to a second position 42 and in the direction of the arrow shown to form a dot pattern 44. The nozzles 46, 48, 50, 52,~and~ 54 in the nozzle plate 12''are '~
fired simultaneously to form, respectively, the two upper cyan dot rows 56 and 58 and the three lower magenta dot rows 60, 62, and 64 2S indicated. .:~
In preparation for maXing a second left-to-right pass as shown in Figure 3B, the nozzle plate 12 is first moved vertically down ~y a distance of one dot row with respect to the print media, D, and then the nozzles 46, 50, 52, and 54 ~' ,~ :............................................................................. .... ~
Case 187353 --` 2 ~ ?~ 2 , , are fired simultaneously to add the dot rows 66, 68, 70, and 72, respectively, in the resulting dot pattern 74.
Referring now to Figure 3C, the cyan nozzle 46 has been moved down one dot row in this next scan to ~orm the added row 76 of cyan dots; a magenta nozzle 50 adds the lower magenta dot row 78; the magenta nozzle 52 also adds the magenta dot row 80, and the magenta nozzle 54 adds the lawermost magenta dot row 82 in the resulting dot pattern 84.
Finally, in the fourth and final left-to-right pass 1~ shown in Figure 3D, these same cyan and magenta nozzles 46, 50, 52, and 54 are simultaneously fired on the left-to-right movement of the nozzle plate 12 indicated by the direction of the arrow to add the cyan dot row 86 and the three magenta dot rows 88 , 90, and 92. This pass completes the solid color area fill pattern indicated generally at 94 in Figure 3D and ; defining a single cyan/magenta interface boundary 96. Thus, it can be seen that the entire solid color area fill pattern 94 in Figure 3D was printed by the ink jet pen of Figures 1 ;~- and 2 above without ever printing more than two adjacent and touching dot rows either simultaneously or in rapid succession.
Referring now to Figures 4A through 4D, these figures illustrate an ink jet printing process operative in accordance ; with the present invention wherein four solid fill areas of cyan, magenta, yellow, and black are formed adjacent to one another and define both vertical and horizontal interface boundaries of separation therebetween. In Figure 4A, an orifice plate 12 is,moved,from the right hand position 98 in the direction of the arrow to the left hand position 100.
` ~ 30 During this pass, the nozzles 102, 104, 106, 108, 110, 112, 114, 116, and 118 on the nozzle plate 12 are fired to form, respectively, the cyan row 120, the yellow row 122, the cyan row 124, the yellow row 126, the black row 128, the magenta row 130, the blac~ row 132, the magenta-row 134, and the black row 136.
Case 187353 2~3~
On the next pass of the orifice plate 12 from the left hand position to the right hand position shown in Figure 4B, the cyan row 138 is formed using the cyan nozzle 102 simultaneously with the formation of the black row 140, the cyan row 142, the yellow row 144, the magenta row 146, the black row 148, the magenta row 150, and the black row 152.
These latter seven rows are formed, respectively, with the firing of nozzles 104, 106, 110, 112, 114, 116, and 118 in the nozzle plate 12 .
In the next right-to-left pass shown in Figure 4C, the cyan, yellow, magenta, and black rows 154, 156, 158, 160, 162, 164, 166, and 16i~ are added as the nozzle plate 12 is first moved one dot row lower than the position shown in Figure 4B
and then across the scan area between nozzle positions 98 and 100.
In the final horizontal pass of thls embodiment, the solid area color fill pattern 170 shown in Figure 4D i5 : completed with the left-to-right printhead motion shown therein to add the completing rows 172, 174, 176, 178, 180, and 182 of the pattern 170. During this fourth right-to-left : pass shown in Figure 4D, the nozzles 102, 104, 107, 110,112, 114, 116 and 118 are fired to form the two upper solid fill areas of cyan and yellow and the two lower sol~d fill areas of magenta and blacX. As seen in this pattern 170, the upper blocks of cyan and yellow are separated from the lower blocks of maganta and black by a continuous horizontal C/M and Y/K
color boundary and by a continuous vertical C/Y and M/K color boundary, The for,mation of: these solid area color fill patterns and their associated C/M and Y/K hori~ontal color : 30 boundries never requires the deposition of more than two adjacent rows of dots either simultaneously or in rapid succassion on a single pass of an ink jet pen. Also, it will be appreciated from the above description of Figures 4A-4 that in forming the continuous C/Y and M/K vertical color boundary, two horizontal adjacent dots of different colors are Case 18735 -~ S~ 2 never deposited either simultaneously or in rapid succession during a single printing pass.
Using this process for forming solid primary color fill areas, the volume of ink deposited per unit area per unit of time is approximately one fourth of the ink drop volume deposited per unit area per unit of time of any known prior art processes. In general, it can be seen that in accordance with the present invention, the deposited ink density is inversely proportional to the number of unique color nozzle columns used.
Various modifications may be made in the above described embodiments without departing from the scope of this invention. For example, the number of nozzIes in each nozzle column can be increased substantially, and the size, shape, dimensions and spacing of these nozzles may be widely varied depending upon the particular ink jet printing application in which this ink jet pen is used. In addition, this pen may be modified for use with ink ej~ction transducers (e.g.
piezoelectric types) other than thermal ink jet heater resistors and for use with ink storage methods other than foam storage. An example of another suitable ink stoxage method and pen body construction is the capillary ink feed system disclosed in U. S. Patent No. 4,791,438 issued to Gary E.
Hanson et al, assigned to the present assignee and incorporated herein by reference.
It should also be understood that the present invention is not limited to the use of a single nozzle plate and a corresponding single,ink jçt pen, but instead may employ, for example, two or more side-by-side pens which have the same adjacent nozzle column relationship as is described above. In such an alternative construction, it may be preferred to use a three color pen together with a separate black pen in a side-by-side arrangement on a common pen carriage member. In this alternative application, two or more separate pens may be replaced independently of each other, and this is particularly Case 187353 desirable where disposable ink jet pens are used in printing applications with a large disparity in ink color demands.
It should further be understood that the present invention is both compatible and useful with super pixelling printing processes where dot-next-to-dot (DND) printing is used for the mixing of colors in a matrix of pixels which themselves constitute super pixels. These matrices may for example be equally sectioned two-by-t-~o or three-by-three super pixels where the divided sections of the super pixel matrix are selectively printed with different colors of inX to form a secondary color fill. For example, the quadrants of a two-by-two super pixel may be selectively printed with the primary ink colors of magenta~yellow, cyan/yellow, and cyan/magenta to form the secondary colors of red, green and blue, respectively. Such super pixelling processes are described, for example, in copending application Serial No.
278,881 of C. S. Chan et al and also in copending application Serial No. (PD 189070~ of Jeffrey L. Trask, both assigned to the present assignee and incorporated herein by reference.
Therefore, while the present invention teaches a novel approach to both time and spatial separation of ink drop (dot) deposition on the printed media, it may be further combined with super pixelling techniques such as those described in the above-identified Trask and Chan et al copending and co-assigned applications to add even a further dimension of time and spatial separation to the ink dot deposition process.
This combination serves to even further enhance the ink drying unifor~ity and print quality of the printed media.
Finally, it will also be understood and appreciated that the present invention is also compatible and useful with dot-on-dot (DOD) printing processes, since many of these types of DOD processes reqùire that a first-deposited drop in a given printed area be dry or substantially dry before a second Case 187353 6~2~ 2 drop is deposited directly thereon. Since single pass drops deposited in accordance with the present invention have a large spatial distribution, the overall drying time is maximized and color bleed is minimized. This feature makes it possible to decrease the time between the first pass drops to the second pass of overlay drops, thereby permitting an increased DOD printing speed.
. ~
. , Case 187353 ~
FOR MINIMIZING B~NDING AND cOLOR BLEED AND
INK JET NOZZLE PLATE FOR USE THEREWITH
Technical Field This invention relates generally to ink jet printing and more particularly to an improved multi-color dot-next-to-dot (DND) ink jet printing process for reducing bandiny and color bleed on printed media. This process serves to improve the overall ink jet print quality on the printed media.
Background_Art Substantial advances have been made in recent years in the field of color ink jet printing, and many of these advances relate to improving the print quality of the printed media, which include plain paper, special papers and various types of transparencies. Typical of these advancements in this art and technology are the various improvements and developments embodied in the Hewlett Packard "PAINTJET"
printer first marketed in August 1987. These are described in some detail in the Hewlett Packard Journal, Volume 39, No. 4, August 1988, incorporated~herein by reference.
In the field of multi-color ink jet printing, it is known to construct ink jet pens (also referred to as printheads) having nozzle or orifice groups of primary colors which are spaced adjacent to one another aiong a length dimension of the printhead and usually perpendicular to printhead motion. When the printhead is moved from side-to-side relative to an adjacent print medium, each color-dedicated nozzle group is fired simultaneously to produce a combined swath width having a total nu~ber of adjacent dot rows equal to the sum of the total numbe~ of nozzles in all of the nozzle groups. For example, in the three color thermal ink jet pen disclosed in U. S. Patent No. 4,812,859 issued to C. S. Chan et al, the three primary color nozzle groups of cyan, yellow, and magenta have sixteen nozzles in each group.
Thus, three separate adjacent color bands totalling forty-Case 187353 ~ -~` 2 ~ 2 2 eight ver~ical dot rows may be produced when the pen is scanned from side-to-side across a print medium moving relative thereto. U. S. Patent No. 4,812,859 issued to C. S.
Chan et al is assigned to the present assignee and is S incorporated herein by re~erence.
Whereas the above identified thermal ink jet color pen disclosed in U. S. Patent No. 4,812,859 performs quite satisfactorily in most respects, there are nevertheless certain ink jet printing applications where the above Chan et al patented approach to multi-color printing may produce either banding or an undesirable color bleed or color mixing.
A11 of these undesirable characteristics in print quality may result from an insufficient drying of ink printed over a given surface area of print media. Thus, this insufficient drying of ink may produce banding in areas of solid color fill where the excessive printed ink volume deposited per unit area per ~ unit of time produces an uneven drying of ink across the width `~ of a printed swath. The ink will bead up at a small angle and in a smoothly rounded curvature across the width of the printed swath, and as a result of this phenomenon the ink at the swath edges will dry faster than the ink in the interior regions of the swath. This produces a lighter color at the swath edges, and this lighter color may be visible as a narrow lighter band extending horizontally across the swath. Hence, the term "banding" has been used in the ink jet printing arts to describe this undesirable characteristic in print quality.
In yet other printing applications, this same excess f ink volume per 4nit of,printed area per unit of time ! may produce an undesirable color bleed or color mixing where different colors are printed in direct side-by-side contact to establish a two-color interface. If these two colors are printed either simultaneously or in sufficiently rapid succession, the wet ink at the two-color interface boundary will bleed laterally across this-boundary and mix with the ~5 other different colored ink which may not be completely dried.
Case 187353 2~2~22 ,, .
This interaction will in turn produce an undesirable visual blurring at the two color interface boundary.
Both of the above problems of banding and color bleed are caused by the side-by-side swath printing over adjacent printed areas of print media with more ink volume per unit area per unit of time than will permit a sufficient and uniform drying of the ink. The print media, such as untreated plain paper, simply cannot sufficiently absorb the ink printed above a given printing speed in the swath area whose width is defined by a number of simultaneously printed adjacent dot rows, such as the sixteen (16) dot rows per swath arranged in the nozzle geometry of the adjacent color printheads in U. S.
Patent No. 4,812,859 identified above.
Disclosure of Invention ~; 15 A general object of this invention is to provide a novel alternative approach to multi-color ink jet printing and one operable in contrast to the -simultaneous printing of adjacent swaths of different colors as described above. This novel approach is useful to either minimize or eliminate the above undesirable print characteristics of banding, color mixing and color bleed. This is accomplished in accordance with the present invention by printing selected dot rows of ink horizontally across a predefined print area and in succession by ink ejected from separate, vertically offset 25 nozzle columns in an ink jet pen or printhead. These selected ~ ~5 dot rows may be printed either simultaneously or in rapid succession, ~or both/ ~ntil all of the nozzles necessary to print a desired image or a solid area flll in the predefined area have be~en fired. The above nozzle firing sequence is such that never more than two adjacent dot rows are printed within the time it takes the nozzle plate to make one traverse or pass across one dimension of the predefined print area of the printed media.
In a preferred embodiment of thè invention, the above process employs a novel nozzle plate geometry wherein a Case 187353 ~2~ 2 , \
plurality of color-dedicated nozzle columns extend vertically along one dimension of the nozzle plate and perpendicular to the direction of nozzle plate horizontal motion described above. Each nozzle column is declicated only to one color of ink such as the primary ink colors of cyan, yello~, magenta or black, and the nozzles in each column are offset or staggered vertically with respect to nozzles in each adjacent column by a distance equal to one dot row. Thus, the selective firing of these nozzles during a horizontal traverse or pass across a print medium is always such that never more than two vertically spaced adjacent dot rows are deposited either simultaneously or in rapid succession. This operation continues as the nozzle plate completes all of its multiple passes over a single print area necessary to print a desired image or solid area fill over the above predefined area. The vertical dimension of this predefined area is substantially coextensive with the vertical dimension of the nozzle plate.
Another object of this invention is to provide a new ;
and improved color printing process of the type described which minimizes banding and color bleed without any sacrifice in printing speed.
Another object of this invention is to provide a new and improved process for ink jet color printing which improves ink drying uniformity over a given printed area and thereby improves the overall print quality of color images ~hich are printed within that area.
Another object is to provide a ne-~ and improved process of the type described which is particularly useful for lmprov1ng color print quality on less-absorbent types of print media having a low drying factor, such as certain grades of office papers and transparencies. -~
A feature of this invention is the provision of a multi-color inX jet printing process of the type described wherein full speed, multiple pass pri-nting is utilized to achieve an increased average drying time between different color dots printed adjacent to one another on a print medium.
Case 187353 ~" 2 ~ 2 .;
;
Another feature o~ this invention is the provision of a novel nozzle plate geometry for use in a multi-color ink jet pen, including spaced apart columns of color-dedicated nozzles therein. The nozzles in each column are vertically offset with respect to nozzles in adjacent columns by a predetermined distance equal to one dot row, and means are provided for fluidically coupling separate colors of ink to each of the columns of nozzles, respectively.
Another feature of this invention is the provision of a new and improved process of the type described which produces a horizontal ink drying boundary between only two solid filled printed rows, so that the total drying area never exceeds an allowable maximum of two dot rows in total width. -;Another feature of this invention is the provision of a color ink jet pen for generating graphic color pixels which are interlaced at the dot row level. This minimizes the visible effects of scan line errors on the printed medium.
Another feature of this invention is the provision of ~`an improved nozzle plate geometry which is operative in combination with currently available print algorithms for the purpose of reduci~g color bleed.
The above objects, features and various related advantages of this invention will become better understood with reference to the following description of the ;~ 25 accompanying drawings.
Brief Description of the Drawinqs ~j Figure 1 is an isom~etric view of a multi-color ink!jet pen having an ink ejection orifice plate whose nozzle arrangement is configured in accordance with the present invention.
Figure 2 is an enlarged plan view of the orifice plate of Figure 1.
Figures 3A through 3D are schematic plan views illustrating the nozzle firing sequence used on four 35 successive passes of the orifice plate over a given print ;~
.:
Case 187353 ?,02~û22 area. These successive passes are used to form adjacent upper and lower solid fill areas of cyan, C, and magenta, M, and these solid fill areas define a single horizontal cyan/magenta interface boundary.
Figures 4A through 4D are schematic plan views illustrating the nozzle fixing sequence used on four successive passes of the orifice plate over a given print area to form solid fill areas of cyan, C, magenta, M, yellow, Y, and black, K, as shown in Figure 4D. These C, M, Y, and K
solid fill areas are separated in Figure 4D by both vertical and horizontal interface boundaries located between the solid fill areas as shown.
Descri~tion of the Preferred Embo~iment ~ ;
Referring now to Figure 1, there is shown a three-color and black ink jet pen which is generally designated as 10 and includes an orifice or nozzle plate 12 which is secured to an~
adjacent barrier layer 14. The ~arrier layer 14 is typically formed of a polymer material such as the well-known insulator VACREL and is secured to a thin film resistor (TFR) substrate 16 whose general construction and architecture are well-known in the art. In the field of thermal ink jet printing, these thin film resistor substrates 16 may be constructed to have photolithographically defined heater resistors (not shown) which are aligned with ink ejection openings in the orifice -; 25 plate 12, and such construction is described in more detail in the above identified He~lett Packard Journal, Volume 39, No. 4, August 1988; inlthe Hewlett PacXard Journal, Volume 36,`
No. S, ~ay 1985, and also in the above identified U. S. Patent No. 4,812,859 issued to C. S. Chan et al. These ink ejection openings are referred to alternatively in this field of ink jet printing as either "orifices" or "nozæles".
The TFR substrate 16 is in turn mounted on one surface of a pen body housing 18 having separate ink storage compartments 20, 22, 24, and 26 therein containing, respectively, the primary ink colors of cyan, magenta, yellow, Case 187353 2 ~ 2 .
and black. This ink storage may be accomplished using a polyurethane foam material in the compartments 20, 22, 24, and 26, and processes used for foam storage in this type of pen body housing construction are disclosed, for example, in U. S.
Patent No. 4,771,295 issued to Jeffrey P. Baker et al, assigned to the present assignee and incorporated herein by reference.
The orifice plate 12 of Figure 1, also shown in the enlarged plan view of Figure 2, includes ~our columns of nozzles 30, 32, 34, and 36 which are fluidically isolated one from another and fed, respectively, with the four primary ink colors of cyan, magenta, yellow, and black as indicated in these figures. Each of these nozzle columns is separated from an adjacent column by a width dimension 'W as indicated in Figure 2 and is offset vertically from'an adjacent nozzle position by a length dimension D. Thus, the center-to-center spacing between adjacent nozzles of like color in any of th~
nozzle columns 30, 32, 34, and 36 is a dimension of four (4) times the number of nozzle columns, or 4D as indicated in Figure 2. Using a print density of 300 dots per inch (DPI), the dimension D will be approximately 0.0033 inches (1/300"), and W will range typically from 25D to 32D.
Referring now in succession to Figures 3A through 3D, the orifice plate or nozzle plate 12 is first moved as shown in Figure 3A from a firs. or starting position 4~ on the right hand side of the fi~ure to a second position 42 and in the direction of the arrow shown to form a dot pattern 44. The nozzles 46, 48, 50, 52,~and~ 54 in the nozzle plate 12''are '~
fired simultaneously to form, respectively, the two upper cyan dot rows 56 and 58 and the three lower magenta dot rows 60, 62, and 64 2S indicated. .:~
In preparation for maXing a second left-to-right pass as shown in Figure 3B, the nozzle plate 12 is first moved vertically down ~y a distance of one dot row with respect to the print media, D, and then the nozzles 46, 50, 52, and 54 ~' ,~ :............................................................................. .... ~
Case 187353 --` 2 ~ ?~ 2 , , are fired simultaneously to add the dot rows 66, 68, 70, and 72, respectively, in the resulting dot pattern 74.
Referring now to Figure 3C, the cyan nozzle 46 has been moved down one dot row in this next scan to ~orm the added row 76 of cyan dots; a magenta nozzle 50 adds the lower magenta dot row 78; the magenta nozzle 52 also adds the magenta dot row 80, and the magenta nozzle 54 adds the lawermost magenta dot row 82 in the resulting dot pattern 84.
Finally, in the fourth and final left-to-right pass 1~ shown in Figure 3D, these same cyan and magenta nozzles 46, 50, 52, and 54 are simultaneously fired on the left-to-right movement of the nozzle plate 12 indicated by the direction of the arrow to add the cyan dot row 86 and the three magenta dot rows 88 , 90, and 92. This pass completes the solid color area fill pattern indicated generally at 94 in Figure 3D and ; defining a single cyan/magenta interface boundary 96. Thus, it can be seen that the entire solid color area fill pattern 94 in Figure 3D was printed by the ink jet pen of Figures 1 ;~- and 2 above without ever printing more than two adjacent and touching dot rows either simultaneously or in rapid succession.
Referring now to Figures 4A through 4D, these figures illustrate an ink jet printing process operative in accordance ; with the present invention wherein four solid fill areas of cyan, magenta, yellow, and black are formed adjacent to one another and define both vertical and horizontal interface boundaries of separation therebetween. In Figure 4A, an orifice plate 12 is,moved,from the right hand position 98 in the direction of the arrow to the left hand position 100.
` ~ 30 During this pass, the nozzles 102, 104, 106, 108, 110, 112, 114, 116, and 118 on the nozzle plate 12 are fired to form, respectively, the cyan row 120, the yellow row 122, the cyan row 124, the yellow row 126, the black row 128, the magenta row 130, the blac~ row 132, the magenta-row 134, and the black row 136.
Case 187353 2~3~
On the next pass of the orifice plate 12 from the left hand position to the right hand position shown in Figure 4B, the cyan row 138 is formed using the cyan nozzle 102 simultaneously with the formation of the black row 140, the cyan row 142, the yellow row 144, the magenta row 146, the black row 148, the magenta row 150, and the black row 152.
These latter seven rows are formed, respectively, with the firing of nozzles 104, 106, 110, 112, 114, 116, and 118 in the nozzle plate 12 .
In the next right-to-left pass shown in Figure 4C, the cyan, yellow, magenta, and black rows 154, 156, 158, 160, 162, 164, 166, and 16i~ are added as the nozzle plate 12 is first moved one dot row lower than the position shown in Figure 4B
and then across the scan area between nozzle positions 98 and 100.
In the final horizontal pass of thls embodiment, the solid area color fill pattern 170 shown in Figure 4D i5 : completed with the left-to-right printhead motion shown therein to add the completing rows 172, 174, 176, 178, 180, and 182 of the pattern 170. During this fourth right-to-left : pass shown in Figure 4D, the nozzles 102, 104, 107, 110,112, 114, 116 and 118 are fired to form the two upper solid fill areas of cyan and yellow and the two lower sol~d fill areas of magenta and blacX. As seen in this pattern 170, the upper blocks of cyan and yellow are separated from the lower blocks of maganta and black by a continuous horizontal C/M and Y/K
color boundary and by a continuous vertical C/Y and M/K color boundary, The for,mation of: these solid area color fill patterns and their associated C/M and Y/K hori~ontal color : 30 boundries never requires the deposition of more than two adjacent rows of dots either simultaneously or in rapid succassion on a single pass of an ink jet pen. Also, it will be appreciated from the above description of Figures 4A-4 that in forming the continuous C/Y and M/K vertical color boundary, two horizontal adjacent dots of different colors are Case 18735 -~ S~ 2 never deposited either simultaneously or in rapid succession during a single printing pass.
Using this process for forming solid primary color fill areas, the volume of ink deposited per unit area per unit of time is approximately one fourth of the ink drop volume deposited per unit area per unit of time of any known prior art processes. In general, it can be seen that in accordance with the present invention, the deposited ink density is inversely proportional to the number of unique color nozzle columns used.
Various modifications may be made in the above described embodiments without departing from the scope of this invention. For example, the number of nozzIes in each nozzle column can be increased substantially, and the size, shape, dimensions and spacing of these nozzles may be widely varied depending upon the particular ink jet printing application in which this ink jet pen is used. In addition, this pen may be modified for use with ink ej~ction transducers (e.g.
piezoelectric types) other than thermal ink jet heater resistors and for use with ink storage methods other than foam storage. An example of another suitable ink stoxage method and pen body construction is the capillary ink feed system disclosed in U. S. Patent No. 4,791,438 issued to Gary E.
Hanson et al, assigned to the present assignee and incorporated herein by reference.
It should also be understood that the present invention is not limited to the use of a single nozzle plate and a corresponding single,ink jçt pen, but instead may employ, for example, two or more side-by-side pens which have the same adjacent nozzle column relationship as is described above. In such an alternative construction, it may be preferred to use a three color pen together with a separate black pen in a side-by-side arrangement on a common pen carriage member. In this alternative application, two or more separate pens may be replaced independently of each other, and this is particularly Case 187353 desirable where disposable ink jet pens are used in printing applications with a large disparity in ink color demands.
It should further be understood that the present invention is both compatible and useful with super pixelling printing processes where dot-next-to-dot (DND) printing is used for the mixing of colors in a matrix of pixels which themselves constitute super pixels. These matrices may for example be equally sectioned two-by-t-~o or three-by-three super pixels where the divided sections of the super pixel matrix are selectively printed with different colors of inX to form a secondary color fill. For example, the quadrants of a two-by-two super pixel may be selectively printed with the primary ink colors of magenta~yellow, cyan/yellow, and cyan/magenta to form the secondary colors of red, green and blue, respectively. Such super pixelling processes are described, for example, in copending application Serial No.
278,881 of C. S. Chan et al and also in copending application Serial No. (PD 189070~ of Jeffrey L. Trask, both assigned to the present assignee and incorporated herein by reference.
Therefore, while the present invention teaches a novel approach to both time and spatial separation of ink drop (dot) deposition on the printed media, it may be further combined with super pixelling techniques such as those described in the above-identified Trask and Chan et al copending and co-assigned applications to add even a further dimension of time and spatial separation to the ink dot deposition process.
This combination serves to even further enhance the ink drying unifor~ity and print quality of the printed media.
Finally, it will also be understood and appreciated that the present invention is also compatible and useful with dot-on-dot (DOD) printing processes, since many of these types of DOD processes reqùire that a first-deposited drop in a given printed area be dry or substantially dry before a second Case 187353 6~2~ 2 drop is deposited directly thereon. Since single pass drops deposited in accordance with the present invention have a large spatial distribution, the overall drying time is maximized and color bleed is minimized. This feature makes it possible to decrease the time between the first pass drops to the second pass of overlay drops, thereby permitting an increased DOD printing speed.
. ~
. , Case 187353 ~
Claims (11)
1. A process for ink jet color printing which includes the steps of:
a. printing dot rows of ink across a predefined area of media to be printed, and b. completing a dot row scan of said predefined area without printing in excess of two dot rows either simultaneously or successively across said predefined area.
a. printing dot rows of ink across a predefined area of media to be printed, and b. completing a dot row scan of said predefined area without printing in excess of two dot rows either simultaneously or successively across said predefined area.
2. The process defined in claim 1 which includes providing an ink jet nozzle plate having a plurality of color-dedicated columns of nozzles therein, with each nozzle column being vertically offset with respect to each adjacent column by a distance equal to the width dimension of one dot row.
3. A process for color ink jet printing which includes ejecting ink to print a plurality of dot rows from a plurality of vertically offset color-dedicated nozzle columns in a nozzle plate which defines one dimension of a first color printed area, and then moving said nozzle plate relative to print media by a predetermined distance, and printing a second area of media adjacent to said first area.
4. The process defined in claim 3 which includes offsetting each nozzle column with respect to each adjacent column by an amount equal to a width dimension of one of said dot rows.
5. A process for scanning and printing a predefined area of print media with an ink jet printhead, which includes the steps of:
a. arranging color-dedicated nozzles in a printhead nozzle plate in adjacent columns of nozzles which are offset along a length dimension of said nozzle plate by the width of one row of dots to be printed horizontally across said predefined area, and b. selectively firing said nozzles to thereby print a plurality of dot rows without depositing in excess of two adjacent dot rows either simultaneously or in succession.
a. arranging color-dedicated nozzles in a printhead nozzle plate in adjacent columns of nozzles which are offset along a length dimension of said nozzle plate by the width of one row of dots to be printed horizontally across said predefined area, and b. selectively firing said nozzles to thereby print a plurality of dot rows without depositing in excess of two adjacent dot rows either simultaneously or in succession.
6. A multi-color ink jet printing process which comprises the steps of:
a. providing ink ejection nozzles in adjacent spaced apart columns for receiving, respectively, different colors of ink in each column, b. offsetting said nozzles vertically in each column by a predetermined distance, c. moving said columns of nozzles a predetermined number of passes with respect to an adjacent print medium, and d. firing a percentage of the nozzles in each column in a sequence that deposits a maximum of two adjacent dot rows either simultaneously or in succession, whereby the printed areas of ink drying on the printed media and defining a boundary between adjacent dot rows is limited to two dot rows.
a. providing ink ejection nozzles in adjacent spaced apart columns for receiving, respectively, different colors of ink in each column, b. offsetting said nozzles vertically in each column by a predetermined distance, c. moving said columns of nozzles a predetermined number of passes with respect to an adjacent print medium, and d. firing a percentage of the nozzles in each column in a sequence that deposits a maximum of two adjacent dot rows either simultaneously or in succession, whereby the printed areas of ink drying on the printed media and defining a boundary between adjacent dot rows is limited to two dot rows.
7. The process defined in claim 6 which further includes firing nozzles in each of said columns in a predetermined spaced vertical sequence therein.
8. A method for multi-color ink jet printing which comprises:
a. providing adjacent columns of ink ejection nozzles for each color, respectively, of a plurality of colors to be printed, b. moving said ink ejection nozzles relative to an adjacent print medium, and c. firing only a predetermined percentage of nozzles within each column on each successive pass of said nozzles across a horizontal dimension of a print scan area until all nozzles required for firing have been fired upon completion of all passes necessary to print a desired color image on said scan area.
a. providing adjacent columns of ink ejection nozzles for each color, respectively, of a plurality of colors to be printed, b. moving said ink ejection nozzles relative to an adjacent print medium, and c. firing only a predetermined percentage of nozzles within each column on each successive pass of said nozzles across a horizontal dimension of a print scan area until all nozzles required for firing have been fired upon completion of all passes necessary to print a desired color image on said scan area.
9. An ink jet pen for use in multi-color ink jet printers, including:
a. a nozzle plate having spaced apart columns of nozzles therein, with nozzles in each column being offset vertically with respect to nozzles in each adjacent column by a predetermined distance, and b. means fluidically coupled to each of said columns for supplying each column of nozzles with a separate color of ink.
a. a nozzle plate having spaced apart columns of nozzles therein, with nozzles in each column being offset vertically with respect to nozzles in each adjacent column by a predetermined distance, and b. means fluidically coupled to each of said columns for supplying each column of nozzles with a separate color of ink.
10. The pen defined in claim 9 which further includes:
a. a support housing having fluidically isolated ink storage compartments therein, and b. a thin film resistor substrate member disposed between said support housing and said nozzle plate for providing firing energy to said nozzle columns and propelling ink from said ink storage compartments to said nozzle columns respectively.
a. a support housing having fluidically isolated ink storage compartments therein, and b. a thin film resistor substrate member disposed between said support housing and said nozzle plate for providing firing energy to said nozzle columns and propelling ink from said ink storage compartments to said nozzle columns respectively.
11. The pen defined in claim 10 wherein said pen includes ink storage compartments of cyan, magenta, yellow, and black ink coupled, respectively, to vertically offset dedicated ink ejection nozzle columns of cyan, magenta, yellow, and black arranged along a length dimension of said nozzle plate.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US45479289A | 1989-12-21 | 1989-12-21 | |
| US454,792 | 1989-12-21 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2023022A1 true CA2023022A1 (en) | 1991-06-22 |
Family
ID=23806108
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA 2023022 Abandoned CA2023022A1 (en) | 1989-12-21 | 1990-08-09 | Multi-color ink jet printing process and color pen for minimizing banding and color bleed and ink jet nozzle plate for use therewith |
Country Status (3)
| Country | Link |
|---|---|
| EP (1) | EP0433556A2 (en) |
| JP (1) | JPH04118250A (en) |
| CA (1) | CA2023022A1 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US11807005B2 (en) | 2018-03-12 | 2023-11-07 | Hewlett-Packard Development Company, L.P. | Nozzle arrangements |
Families Citing this family (19)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3227284B2 (en) * | 1992-10-30 | 2001-11-12 | キヤノン株式会社 | Ink jet recording method and ink jet recording head |
| DE69330081T2 (en) * | 1992-10-30 | 2001-08-30 | Canon Kk | Ink jet recording system and device |
| JPH07276630A (en) * | 1994-04-12 | 1995-10-24 | Rohm Co Ltd | Ink jet print head and ink jet printer |
| US5654744A (en) * | 1995-03-06 | 1997-08-05 | Hewlett-Packard Company | Simultaneously printing with different sections of printheads for improved print quality |
| JPH10278317A (en) | 1997-02-04 | 1998-10-20 | Seiko Epson Corp | Ink jet recorder |
| EP0893265A3 (en) | 1997-07-25 | 2000-05-10 | Seiko Epson Corporation | Ink-jet printing apparatus |
| JP4028067B2 (en) | 1998-02-26 | 2007-12-26 | 東芝テック株式会社 | Driving method of recording head |
| DE10057061C1 (en) | 2000-11-17 | 2002-05-23 | Koenig & Bauer Ag | Printing device e.g. for offset printing plate manufacture, uses ink jet printing heads positioned in spaced parallel rows |
| US6922203B2 (en) * | 2001-06-06 | 2005-07-26 | Hewlett-Packard Development Company, L.P. | Barrier/orifice design for improved printhead performance |
| JP2009241444A (en) * | 2008-03-31 | 2009-10-22 | Fujifilm Corp | Liquid droplet ejecting apparatus and image forming method |
| JP5707805B2 (en) * | 2010-09-15 | 2015-04-30 | 株式会社リコー | Image forming apparatus |
| JP2014004780A (en) * | 2012-06-26 | 2014-01-16 | Riso Kagaku Corp | Inkjet printer |
| JP5878097B2 (en) * | 2012-08-29 | 2016-03-08 | 富士フイルム株式会社 | Inkjet recording method |
| JP2014046479A (en) * | 2012-08-29 | 2014-03-17 | Fujifilm Corp | Inkjet recording method, and printed matter |
| JP2014046480A (en) * | 2012-08-29 | 2014-03-17 | Fujifilm Corp | Inkjet recording method, and printed matter |
| JP5654535B2 (en) * | 2012-08-29 | 2015-01-14 | 富士フイルム株式会社 | Inkjet recording method and printed matter |
| JP5964721B2 (en) * | 2012-10-25 | 2016-08-03 | 富士フイルム株式会社 | Inkjet recording apparatus and inkjet recording method |
| JP6426022B2 (en) * | 2015-02-13 | 2018-11-21 | 株式会社ミマキエンジニアリング | Liquid discharge apparatus and liquid discharge method |
| WO2019177576A1 (en) * | 2018-03-12 | 2019-09-19 | Hewlett-Packard Development Company, L.P. | Nozzle arrangements and supply channels |
-
1990
- 1990-08-09 CA CA 2023022 patent/CA2023022A1/en not_active Abandoned
- 1990-08-30 EP EP19900116669 patent/EP0433556A2/en not_active Withdrawn
- 1990-12-21 JP JP41350590A patent/JPH04118250A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US11807005B2 (en) | 2018-03-12 | 2023-11-07 | Hewlett-Packard Development Company, L.P. | Nozzle arrangements |
Also Published As
| Publication number | Publication date |
|---|---|
| EP0433556A2 (en) | 1991-06-26 |
| JPH04118250A (en) | 1992-04-20 |
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