WO2013016860A1 - 喷墨打印装置及其打印方法 - Google Patents

喷墨打印装置及其打印方法 Download PDF

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Publication number
WO2013016860A1
WO2013016860A1 PCT/CN2011/077839 CN2011077839W WO2013016860A1 WO 2013016860 A1 WO2013016860 A1 WO 2013016860A1 CN 2011077839 W CN2011077839 W CN 2011077839W WO 2013016860 A1 WO2013016860 A1 WO 2013016860A1
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WIPO (PCT)
Prior art keywords
ink
nozzles
printing
color
ejecting
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Application number
PCT/CN2011/077839
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English (en)
French (fr)
Inventor
张原�
Original Assignee
北京美科艺数码科技发展有限公司
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Application filed by 北京美科艺数码科技发展有限公司 filed Critical 北京美科艺数码科技发展有限公司
Priority to US13/982,273 priority Critical patent/US9315022B2/en
Priority to PCT/CN2011/077839 priority patent/WO2013016860A1/zh
Priority to CN201180066357.4A priority patent/CN103370200B/zh
Publication of WO2013016860A1 publication Critical patent/WO2013016860A1/zh

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    • 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
    • B41J2/135—Nozzles
    • B41J2/14—Structure thereof only for on-demand ink jet heads
    • B41J2/1433—Structure of nozzle plates
    • 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
    • B41J11/00—Devices or arrangements  of selective printing mechanisms, e.g. ink-jet printers or thermal printers, for supporting or handling copy material in sheet or web form
    • B41J11/0015—Devices or arrangements  of selective printing mechanisms, e.g. ink-jet printers or thermal printers, for supporting or handling copy material in sheet or web form for treating before, during or after printing or for uniform coating or laminating the copy material before or after printing
    • 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
    • B41J2/135—Nozzles
    • B41J2/145—Arrangement thereof
    • 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
    • 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
    • B41J2/2107—Ink jet for multi-colour printing characterised by the ink properties
    • B41J2/2114—Ejecting specialized liquids, e.g. transparent or processing liquids

Definitions

  • the present invention relates to an inkjet printing apparatus and a printing method thereof, and more particularly to a color inkjet printing apparatus for improving the quality of a printed image and shortening the width of a bottom plate of a nozzle while ensuring print yield, and realizing the use of the color inkjet printing apparatus A method of printing white ink or clear ink or other underlying ink function.
  • Inkjet printing technology is a printing technique in which ink is ejected onto a print medium by a head to form an image or text.
  • Inks are generally classified into coated inks (white inks, clear inks or other underprint inks) and color inks.
  • white inks are used to print "background colors” on non-white print media to increase the vividness of printed images or The "foreground color” is printed on the transparent print medium to form a reflected image.
  • the printing resolution of the white ink is relatively high, and generally the printing resolution is higher than the printing resolution of the printed image, such as 1440*1440dpi.
  • the printing resolution of the printed image such as 1440*1440dpi.
  • it is generally covered by a transparent protective layer on the color image.
  • a UV lamp curing device is disposed on each side of the printing carriage of the inkjet printing device. Since there is a superimposition of the ground color and the printed image during the printing process, it is required that the ink droplet of the ground color has been printed when the image is printed. Curing, that is, it is required to be cured while printing, otherwise there will be a mixture of ink droplets of various colors, which affects the quality of inkjet printing.
  • the width of the UV lamp curing device must be irradiated to the entire printing width, that is, the width of the UV lamp curing device needs to be greater than or equal to the total width of the nozzle array on the bottom plate of the trolley, and the larger the irradiation width of the UV lamp curing device, the more expensive it is.
  • the scanning type ink-jet printing device of the scanning type there are mainly two methods for hitting the white background in the prior art, one method is to first print the white ink, and then the printing medium is poured after the white ink is printed. Go back and print the color image on the printing medium with white ink.
  • the nozzle arrangement method is shown in Figure 1. All the nozzles are arranged side by side on an axis.
  • This printing method is difficult because the accuracy of the paper feeding direction is not accurate enough.
  • the printing accuracy of the paper feed direction is ensured, and the printing time is correspondingly increased;
  • another method vertically aligns the white ink and the nozzle for jetting the color ink, wherein the nozzle for jetting the white ink sets the paper feed end of the printing medium, and the white ink is sprayed.
  • the nozzle first sprays white ink on the printing medium, and then the nozzle that ejects the color ink ejects a color image on the printing medium that has ejected the white ink.
  • This method is suitable for a printer with a small number of nozzles, as shown in FIG.
  • the nozzles for jetting color inks are located in another row; in industrial printing, it is common to use multiple nozzles in series to increase the print yield. For example, two nozzles for each color ink are printed, as shown in Fig. 4, two of the spray coating inks are shown.
  • the nozzle orifices are arranged in a row after the end and end of the nozzle, and the nozzles of the nozzles for jetting the color ink are connected in series and then in another row.
  • the width of the bottom plate of the mounting nozzles is increased, and the corresponding ink curing device is provided.
  • the width requirement is increased.
  • a UV lamp can be used to illuminate all the printing areas.
  • four rows of nozzles are installed in the vertical direction as shown in Fig. 4, two UV lamp curing devices are needed or used.
  • a wider UV lamp curing device can illuminate all of the print areas.
  • UV curing devices are very expensive, resulting in a significant increase in printing costs, while the increased width of the print head mounting plate also reduces the smoothness of the print car movement during printing.
  • an object of the present invention is to provide a color inkjet printing device capable of coating ink with improved print image quality while ensuring print yield and saving printing cost, and realizing the ink jet printing device using the same.
  • the printing method is to provide a color inkjet printing device capable of coating ink with improved print image quality while ensuring print yield and saving printing cost, and realizing the ink jet printing device using the same.
  • the invention provides an inkjet printing device, characterized in that it comprises at least four nozzles, all of which are nozzles of the same type, wherein at least two nozzles are used for spraying coating ink, and the other nozzles are used for spraying color inks.
  • the nozzles for spraying the coating ink are interpolated or arranged side by side in a row, the nozzles for ejecting the color ink are arranged side by side in another row; in the direction of movement of the printing medium, the nozzles for ejecting the color ink eject the same color
  • the nozzle orifices of the ink are connected in series one end, and the nozzles for ejecting different color inks in the nozzle for ejecting color ink are arranged side by side.
  • the coating ink is a white ink.
  • the coating ink is a transparent ink.
  • the number of the heads for ejecting the coating ink may be the same as or different from the number of the heads for ejecting the color ink of the same color.
  • the number of the ink jet heads for ejecting the same color is the same.
  • the invention provides an inkjet printing method, in particular,
  • the nozzles for spraying coating inks are used for jetting color inks
  • the nozzles are respectively arranged in two rows; the nozzles for spraying the coating ink are interpolated or arranged side by side; in the direction of the movement of the printing medium, the nozzles for ejecting the color inks are sprayed with the nozzles of the same color ink.
  • the nozzles for ejecting color ink the nozzles for ejecting ink of different colors are arranged side by side.
  • the nozzle for spraying the coating ink adopts an N-pass printing method, and the nozzle for ejecting color ink adopts 2N times. The printing method, where N is a natural number greater than zero.
  • the nozzle for spraying the coating ink adopts a two-pass printing method
  • the nozzle for jetting the color ink adopts a four-pass printing method
  • the coating ink is a white ink.
  • the coating ink is a transparent ink.
  • the invention has the following advantages and effects: 1) printing coating ink and printing color ink are completed once, the color registration is accurate, the inkjet printing yield is high; 2) the printing of the coating ink during printing The resolution is higher than the printing resolution of the printed image or the printing density is higher than the printing density of the printed image, which can ensure that the coating ink covers the entire printing area and improve the vividness of the printed image color; 3) the printing image is printed many times during the printing process.
  • Printing method the number of printing passes is twice the number of printing inks of the coating ink, the printing precision is high, and the streaking problem of single-pass printing is avoided; 4) because the printing precision of the coating ink coating layer in the image requires no color image The printing precision is high.
  • the nozzles for spraying the coating ink are arranged side by side or interpolated in one row, and the nozzles for jetting different color inks are arranged side by side in another row to ensure that the coating ink covers the entire printing area.
  • the width of the nozzle bottom plate is greatly shortened, the requirement for the width of the UV curing device is reduced, and the weight of the printing carriage is reduced.
  • the cost of inkjet printing to improve the stability of the work trolley.
  • FIG. 1 is a schematic structural view of an inkjet printing device of the present invention
  • FIG. 2 is a schematic view showing the arrangement of the heads in the prior art inkjet printing device
  • FIG. 3 is a schematic view showing another arrangement of the nozzles when the number of nozzles for jetting the same color ink is one in the prior art
  • FIG. 4 is a schematic view showing the arrangement of the nozzles when the number of nozzles for jetting the same color ink is two in the prior art
  • 5a is a schematic view showing the arrangement of the heads in the inkjet printing device according to an embodiment of the present invention.
  • Figure 5b is a schematic view showing another arrangement of the head in the ink jet printing apparatus according to an embodiment of the present invention.
  • 6a is a schematic view showing the arrangement of the heads in the inkjet printing device according to another embodiment of the present invention.
  • 6b is another schematic view showing the arrangement of the nozzles in the inkjet printing device according to another embodiment of the present invention.
  • Figure 7 is a schematic view showing the arrangement of the heads in the ink jet printing apparatus according to still another embodiment of the present invention.
  • This embodiment is an inkjet printing apparatus and a printing method when a color image is printed on a non-white printing medium.
  • the printing medium is a color other than white
  • the ink jet printing apparatus 60 in this embodiment includes a printing carriage 61 on which a head plate 611 for ejecting ink droplets onto a printing medium is mounted, and the ink jet printing apparatus 61 in this embodiment.
  • a printing platform 63 Also included is a printing platform 63, a rail beam 62 and a control system 64 that controls the printing carriage 61 to eject ink drops onto the print medium on the printing platform 63 during the reciprocating movement of the rails 62 to form a desired printed image or Text.
  • ten nozzles are mounted on the nozzle bottom plate 611 of the inkjet printing device.
  • the ten nozzles are nozzles of the same model, and each nozzle has n nozzle holes, and the nozzle nozzle spacing is d.
  • Ten nozzles are arranged in two rows. The nozzle holes of all the nozzles are arranged in parallel with the moving direction of the printing medium, and the nozzles are arranged in the same direction.
  • Each ink is printed by two nozzles.
  • the nozzles 9, 10 are for jetting white (W) ink
  • the nozzles 1, 2 are for jetting cyan (C) ink
  • the nozzles 3, 4 are for jetting magenta (M) ink
  • the nozzles 5, 6 are for jetting yellow (Y) Ink
  • nozzles 7, 8 for jetting black (K) ink
  • nozzles 9, 10 for jetting white (W) ink are interpolated at the paper feed end of the ink jet printing device
  • jetting cyan (C) ink, magenta (M) ink, yellow (Y) ink, black (K) ink nozzles are arranged side by side at the paper exit end of the inkjet printing device; in the direction of the movement of the printing medium, the nozzles of the white ink nozzles 9, 10 are ejected and the color ink is ejected
  • the nozzle holes of the nozzles 1-8 do not overlap.
  • the spacing of adjacent nozzles is equal along the direction of movement of the nozzle.
  • two nozzle nozzles for ejecting the same color ink are connected in series, that is, the nozzles of the nozzles 1 and the nozzles 2 are connected end to end, the nozzles of the nozzles 3 and the nozzles 4 are connected end to end, and the nozzles 5 are connected.
  • the nozzle holes of the nozzles 6 are connected in series with each other, and the nozzles 7 and the nozzles of the nozzles 8 are connected in series.
  • a UV lamp curing device 71, 72 is mounted on each side of the head plate 611 to cure the ink drops ejected onto the printing medium.
  • the width of the nozzle bottom plate is shortened by the length of one nozzle, so that the requirement of the width of the UV lamp curing device is reduced by the inkjet printing device, and the weight of the printing trolley is reduced and improved.
  • the white ink-jetting heads 9, 10 of the present invention can also be arranged side by side, and the nozzles for ejecting the color ink are arranged in the same manner as in Fig. 5a.
  • the white ink jetting nozzles 9, 10 first form a white background on the printing medium, and the UV lamp curing devices 71, 72 cure the ink droplets ejected onto the printing medium, and then eject the color ink nozzles 1 - 8 Print the desired color image on the cured white background of the print media. Since the one-pass printing method is easy to reduce the life of the head, the accuracy of the printed image is difficult to guarantee. In order to improve the accuracy of the printed image, multi-pass printing can be used, but the corresponding print yield is reduced.
  • the head of the inkjet white ink adopts a two-pass (two-pass) printing mode, and when the nozzles 9 and 10 for ejecting the white ink are interpolated, the width of the nozzle of the white ink nozzles 9, 10 is sprayed along the moving direction of the printing medium.
  • the white cover layer print resolution is twice the color image print resolution, when jetting white ink
  • the width of the nozzles for jetting the white ink nozzles 9 and 10 along the moving direction of the printing medium is the width of the nozzles of the single nozzles, that is, nd, and when printing, the nozzles 9 and 10 respectively eject a drop of ink droplets.
  • the printed image pixels are superimposed to form desired image data.
  • the ink amount of the white cover layer is generally increased, ensuring that the white ink covers the entire print area, and the vividness of the color of the printed image is improved.
  • the two nozzles for ejecting each color ink are respectively arranged one after the other, and are arranged side by side in another row.
  • the total width of the nozzle of the color ink nozzle of the nozzle is 2nd, so when the nozzle for spraying the coating ink adopts a two-pass printing method,
  • the nozzle that ejects the color ink is a four-pass printing method, which makes the printed image more accurate.
  • the ink jet printing method of the present invention can improve the accuracy of a printed image while ensuring that the white ink covers the entire print area.
  • the nozzle for jetting white ink may also adopt a three-pass printing mode, and the corresponding nozzle for jetting color ink adopts a six-pass printing mode. The more the number of print passes, the higher the accuracy of the printed image, the lower the corresponding print yield, and the compromise can be handled according to the actual printing needs.
  • This embodiment is an inkjet printing apparatus and a printing method when a color image is printed on a transparent medium.
  • a white ink is used to print a color image on a transparent medium, and then the color image is covered with white ink, and the observer observes the printed image through the transparent medium.
  • the nozzle bottom plate 611 of the inkjet printing device of the present invention comprises ten nozzles, the ten nozzles are the same type of nozzles, and the ten nozzles are arranged in two rows, and the nozzle holes are arranged in the direction and printing of all the nozzles.
  • the movement direction of the media is parallel, and the discharge direction of all the nozzles is uniform, and each ink is printed by two nozzles.
  • the nozzles 9, 10 are for jetting white (W) ink
  • the nozzles 1, 2 are for jetting cyan (C) ink
  • the nozzles 3, 4 are for jetting magenta (M) ink
  • the nozzles 5, 6 are for jetting yellow (Y)
  • the ink, the nozzles 7, 8 are used to eject the black (K) ink
  • the nozzles 9, 10 for ejecting the white (W) ink are arranged side by side at the paper exit end of the ink jet printing device, and the cyan (C) ink and magenta (M) are sprayed.
  • the nozzles of the ink, the yellow (Y) ink, and the black (K) ink are arranged side by side at the paper feeding end of the inkjet printing device, wherein the two nozzle orifices for printing the same color ink are serially connected end to end, that is, the nozzle 1 and the nozzle 2
  • the nozzles are connected end to end, the nozzles 3 and the nozzles of the nozzles 4 are connected in series, the nozzles 5 and the nozzles of the nozzles 6 are connected in series, and the nozzles 7 and the nozzles of the nozzles 8 are connected in series.
  • the white ink-jetting heads 9, 10 of the present invention can also be interpolated, and the nozzles 1-8 for ejecting the color ink are arranged in the same manner as in Fig. 6a.
  • the heads 1-8 for ejecting color ink first print a color image on a transparent print medium, the UV lamp curing devices 71, 72 cure the printed image, and then spray the white ink nozzles 9, 10 in a cured color image.
  • the white ink is sprayed on, and the observer observes the printed image through the transparent medium.
  • the printing method is the same as the printing method in the embodiment.
  • the nozzles 9 and 10 for spraying the white ink adopt the two-pass printing method, and the nozzles 1-8 for jetting the color ink are used. Four-pass printing method.
  • This embodiment is another inkjet printing apparatus for printing a color image on a non-white printing medium and a corresponding printing method.
  • a plurality of white ink nozzles may be interpolated or arranged side by side to increase printing.
  • the concentration of white ink in the area increases the vividness of the printed image.
  • three nozzles 9, 10, 11 for jetting white ink are arranged side by side.
  • the nozzles 9, 10, 11 can also be interpolated. It is also possible to interpolate or arrange four or more nozzles that spray white ink side by side according to actual needs.
  • the arrangement of the jet color ink jet heads 1-8 is identical to that of the heads 1-8 for jetting color inks in the first embodiment.
  • the nozzle for spraying the coating ink can be sprayed with a transparent color ink or other under color ink such as gray ink according to actual printing requirements.
  • a transparent color ink or other under color ink such as gray ink according to actual printing requirements.
  • the principle of the nozzle arrangement and the printing method is the same as the nozzle arrangement and printing method when the coating ink is a white ink.
  • the nozzles of the plurality of spray coating inks are interpolated or arranged side by side in a row, and the nozzle orifices for ejecting the color ink are arranged end by end in another row to ensure that the coating ink covers the entire printing area while being greatly shortened.
  • the width of the nozzle bottom plate reduces the requirement for the width of the UV lamp curing device, and the cost saving can also improve the stability of the inkjet printing car work.

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Abstract

一种喷墨打印装置（60），包括至少四个喷头（1、2、3、4、5、6、7、8、9、10），所有喷头为同一型号，其中至少两个喷头（9、10）用于喷射涂层油墨，其余喷头（1、2、3、4、5、6、7、8）用于喷射彩色油墨，所述用于喷射涂层油墨的喷头（9、10）并排排列或插值排列于一行中，所述用于喷射彩色油墨的喷头（1、2、3、4、5、6、7、8）并排排列于另一行中；沿打印介质运动方向，喷射彩色油墨的喷头中喷射同一色油墨的喷头喷孔首尾串接，喷射不同色油墨的喷头并排排列。通过将喷射涂层油墨的喷头并排排列或插值排列于一行中，喷射彩色油墨喷头的喷孔首尾串接后并排排列于另一行中，实现在保证涂层油墨覆盖整个打印区域的同时，缩短了喷头底板（611）的宽度，降低对UV固化装置宽度的要求，节约成本同时也能提高喷墨打印小车（61）工作的稳定性。

Description

喷墨打印装置及其打印方法 技术领域
本发明涉及一种喷墨打印装置及其打印方法，尤其涉及一种在保证打印产量的前提下提高打印图像质量，缩短喷头底板宽度的彩色喷墨打印装置及采用该彩色喷墨打印装置实现打白墨或透明油墨或其它底色油墨功能的打印方法。
背景技术
喷墨打印技术是通过喷头喷射油墨到打印介质上形成图像或文字的一种打印技术。油墨一般分为涂层油墨（白色油墨、透明色油墨或其它底色油墨）和彩色油墨，通常白色油墨被用于在非白打印介质上打印“背景色”以增加打印图像的鲜艳度或者在透明打印介质上打印“前景色”以形成反射图像。在打印“背景色”时，先使用白色油墨在非白打印介质上形成白色背景并进一步在其上打印彩色图像，然后从打印面看到形成的最终图像；在打印“前景色”时，先使用彩色油墨在透明打印介质上形成彩色图像，随后将白色油墨应用在彩色油墨上，并透过透明的打印介质观察到最终形成的图像。由于彩色油墨一般是有点透明的，在彩色打印介质上打印图像一般会显得图像的颜色看起来有点褪色，因此打印机常常首先在要打印图像的非白打印介质的表面的整个打印区域之上打印一层完全不透明的白色油墨，然后在打印白色油墨的打印介质上打印图像，以保证图像的鲜艳程度。在打印白色油墨时，为保证白色油墨均匀的覆盖整个打印区域，白色油墨的打印分辨率的要求较高，一般其打印分辨率高于打印图像的打印分辨率，如1440*1440dpi。现有技术中为保证已打印的彩色图像的不脱落，一般通过在彩色图像上覆盖一层透明的保护层。
现有技术中喷墨打印装置的打印小车的两侧各设置一UV灯固化装置，由于在打印过程中，存在底色和打印图像的叠加，这就要求在打印图像时底色的墨滴已固化，即要求边打印边固化，否则将存在各色墨滴混色，影响喷墨打印质量。因此要求UV灯固化装置的宽度必须照射到整个打印幅宽，即UV灯固化装置的宽度需大于等于小车底板上喷头排列的总宽，而UV灯固化装置照射宽度越大其价格也越贵。对于打印方式为扫描式的收放纸喷墨打印装置，现有技术中打白色背景的方法主要有以下两种，一种方法是先打印白色油墨，在打印完白色油墨后再将打印介质倒回去再在已打印白色油墨的打印介质上再打印彩色图像，其喷头排列方法如图1所示，所有喷头并排排列于一轴线上，采用这种打印方法由于走纸方向精度不够精准，很难保证走纸方向的打印精度，同时其打印时间相应增加；另一种方法将喷射白色油墨和喷射彩色油墨的喷头垂直排列，其中喷射白色油墨的喷头设置打印介质的进纸端，喷射白色油墨的喷头先喷射白色油墨于打印介质上，然后喷射彩色油墨的喷头喷射彩色图像于已喷射白色油墨的打印介质上，对于喷头排数较少的打印机采用这种方法比较合适，如图3所示，两排喷头，每色油墨采用一个喷头打印，喷射涂层油墨的喷头位于一排，喷射彩色油墨的喷头位于另一排；工业打印中，通常采用串接多个喷头来提高打印产量，以每色油墨采用两个喷头打印为例，如图4所示，喷射涂层油墨的两个喷头喷孔首尾串接后位于一排，喷射彩色油墨的各喷头喷孔首尾串接后位于另一排，由于喷头数量较多，将使得安装喷头的底板宽度增加，相应的对油墨固化装置宽度的要求增高，一般垂直方向安装三排喷头时，采用一个UV灯就能照射到所有打印区域，按照图4所示在垂直方向安装四排喷头时，则需要两个UV灯固化装置或者使用一个更宽的UV灯固化装置才能照射到所有打印区域，通常UV固化装置的价格非常昂贵，使得打印成本显著增加，同时喷头安装底板的宽度增加也使得打印过程中打印小车运动的平稳性降低。
发明内容
针对现有技术存在的问题，本发明的目的在于提供一种提高打印图像质量的同时保证打印产量、节约打印成本的可打涂层油墨的彩色喷墨打印装置及采用这种喷墨打印装置实现的打印方法。
本发明提出一种喷墨打印装置，其特征在于，包括至少四个喷头，所有安装喷头为同一型号喷头，其中至少两个喷头用于喷射涂层油墨，其余喷头用于喷射彩色油墨，所述用于喷射涂层油墨的喷头插值排列或并排排列于一行，所述用于喷射彩色油墨的喷头并排排列于另一行；沿打印介质运动方向，所述用于喷射彩色油墨的喷头中喷射同一色油墨的喷头喷孔首尾串接，所述用于喷射彩色油墨的喷头中喷射不同色油墨的喷头并排排列。
上述喷墨打印装置中，所述涂层油墨为白色油墨。
上述喷墨打印装置中，所述涂层油墨为透明色油墨。
上述喷墨打印装置中，所述用于喷射涂层油墨的喷头数量与所述用于喷射同一色彩色油墨的喷头数量可以相同也可以不同。
上述喷墨打印装置中，所述用于喷射同一色彩色油墨喷头的数量相同。
本发明提出一种喷墨打印方法，具体为，
提供至少四个喷头，所有喷头为同一型号喷头，其中至少两个喷头用于喷射涂层油墨，其余喷头用于喷射彩色油墨；所述用于喷射涂层油墨的喷头与用于喷射彩色油墨的喷头分别排在两行中；所述用于喷射涂层油墨的喷头插值排列或并排排列；沿打印介质运动方向，所述用于喷射彩色油墨的喷头中喷射同一色油墨的喷头喷孔首尾串接，所述用于喷射彩色油墨的喷头中喷射不同色油墨的喷头并排排列，喷墨打印时，所述喷射涂层油墨的喷头采用N遍打印方式，所述喷射彩色油墨的喷头采用2N遍打印方式，其中N为大于0的自然数。
上述喷墨打印方法中，喷墨打印时，所述喷射涂层油墨的喷头采用两遍打印方式，所述喷射彩色油墨的喷头采用四遍打印方式。
上述喷墨打印方法中，所述涂层油墨为白色油墨。
上述喷墨打印方法中，所述涂层油墨为透明色油墨。
与现有技术相比，本发明具有如下优点与效果：1）打印涂层油墨和打印彩色油墨一次走纸完成，其套色精确，喷墨打印产量高；2）打印过程中涂层油墨的打印分辨率高于打印图像的打印分辨率或者其打印浓度高于打印图像的打印浓度，能够保证涂层油墨覆盖整个打印区域，提高打印图像色彩的鲜艳度；3）打印过程中打印图像采用多遍打印方式，其打印遍数是涂层油墨打印遍数的两倍，打印精度高，避免单遍打印存在的斑纹问题；4）由于图像中对涂层油墨覆盖层的打印精度要求没有彩色图像的打印精度的要求高，本发明中将喷射涂层油墨的喷头并排排列或插值排列于一行中，将喷射不同色彩色油墨的喷头并排排列于另一行中，在保证涂层油墨覆盖整个打印区域的同时，大大缩短喷头底板的宽度，降低对UV固化装置宽度的要求，降低打印小车重量，节约成本的同时提高喷墨打印小车工作的稳定性。
附图说明
图1为本发明中喷墨打印装置结构示意图；
图2为现有技术喷墨打印装置中的喷头排列示意图；
图3为现有技术中喷射同色油墨的喷头数量为一个时喷头的另一排列示意图；
图4为现有技术中喷射同色油墨的喷头数量为两个时喷头的排列示意图；
图5a为本发明一个实施例中喷墨打印装置中喷头的排列示意图；
图5b为本发明一个实施例中喷墨打印装置中喷头的另一排列示意图；
图6a为本发明另一实施例中喷墨打印装置中喷头的排列示意图；
图6b为本发明另一实施例中喷墨打印装置中喷头的另一排列示意图；
图7为本发明又一实施例中喷墨打印装置中喷头的排列示意图。
具体实施方式
实施例一
本实施例为在非白打印介质上打印彩色图像时的喷墨打印装置及打印方法。一般当打印介质为除白色以外的其它颜色时，需先在打印介质的打印区域内打印一层白色油墨以保证打印图像的鲜艳度。如图1所示，本实施例中的喷墨打印装置60包括打印小车61，打印小车61上安装用于喷射墨滴到打印介质上的喷头底板611，本实施例中的喷墨打印装置61还包括打印平台63，导轨梁62及控制系统64，控制系统64控制打印小车61沿导轨梁62做往复运动的过程中喷射墨滴于打印平台63上的打印介质上形成所需的打印图像或文字。
如图5a所示，本实施例中喷墨打印装置的喷头底板611上安装十个喷头，该十个喷头为同一型号的喷头，每个喷头上有n个喷孔，喷头喷孔间距为d，十个喷头分两行设置，所有喷头的喷孔排列方向与打印介质的运动方向平行，且喷头的排列方向一致，每色油墨均采用两个喷头打印。喷头9、10用于喷射白色（W）油墨，喷头1、2用于喷射青色（C）油墨，喷头3、4用于喷射品红色（M）油墨，喷头5、6用于喷射黄色（Y）油墨、喷头7、8用于喷射黑色（K）油墨，用于喷射白色（W）油墨的喷头9、10插值排列于喷墨打印装置的进纸端，喷射青色（C）油墨、品红色（M）油墨、黄色（Y）油墨、黑色（K）油墨的喷头并排排列于喷墨打印装置的出纸端；沿打印介质运动方向，喷射白色油墨喷头9、10的喷孔与喷射彩色油墨喷头1-8的喷孔不重叠。沿喷头运动方向，相邻喷头的间距相等。喷射彩色油墨的喷头1-8中喷射同一色油墨的两个喷头喷孔首尾串接，即喷头1与喷头2的喷孔首尾串接、喷头3与喷头4的喷孔首尾串接、喷头5与喷头6的喷孔首尾串接，喷头7与喷头8的喷孔首尾串接。在喷头底板611的两侧各安装一UV灯固化装置71、72以固化喷射到打印介质上的墨滴。由于喷射白色油墨的两个喷头插值排列于同一行中，使得喷头底板宽度缩短近一个喷头的长度，从而使得喷墨打印装置对UV灯固化装置宽度的要求降低，使打印小车的重量减轻，提高打印过程中打印小车运行的稳定性。
如图5b所示，本发明中的喷射白色油墨的喷头9、10还可以并排排列，喷射彩色油墨的喷头的排列方式与图5a中的一致。
喷墨打印时，喷射白色油墨的喷头9、10先在打印介质上形成一白色背景，UV灯固化装置71、72对喷射到打印介质上的墨滴进行固化，然后喷射彩色油墨的喷头1-8在打印介质的已固化白色背景上打印所需的彩色图像。由于one-pass（单遍）打印方式容易降低喷头的使用寿命，且打印图像的精确度难于保证。为提高打印图像的精确度可以采用multi-pass（多遍）打印方式，但相应的会使打印产量降低。本实施例中喷墨白色油墨的喷头采用two-pass（两遍）打印方式，当喷射白色油墨的喷头9、10插值排列时，沿打印介质运动方向喷射白色油墨喷头9、10喷孔的宽度为单个喷头喷孔的宽度加二分之一喷孔间距，即为nd+d/2,喷墨打印时，白色覆盖层的打印分辨率为彩色图像打印分辨率的两倍，当喷射白色油墨的喷头9、10并排排列时，沿打印介质运动方向喷射白色油墨喷头9、10喷孔的宽度为单个喷头的喷孔宽度，即为nd，打印时，喷头9和10各喷射一滴墨滴与打印图像像素点上叠加形成所需的图像数据。由于白色覆盖层中同一点数据喷射两遍墨或者其打印分辨率为彩色图像的两倍，使得白色覆盖层的墨量总体增加，保证白墨覆盖整个打印区域，提高打印图像色彩的鲜艳度。喷射各彩色油墨的两喷头分别首尾串接后并排位于另一排，喷头彩色油墨喷头的喷孔总宽为2nd，因此当喷射涂层油墨的喷头采用two-pass（两遍）打印方式时，喷射彩色油墨的喷头即为four-pass（四遍）打印方式，从而使打印图像的精确度更高些。因此采用本发明的喷墨打印方法能够在保证白色油墨覆盖整个打印区域的同时使打印图像的精确度提高。根据实际打印需要，本发明的喷墨打印方法中，喷射白色油墨的喷头也可应采用三遍打印方式，相应的喷射彩色油墨的喷头采用六遍打印方式。打印遍数越多，其打印图像的精确度越高，相应的打印产量会越低，根据实际打印需要可以折中处理。
实施例二
本实施例为在透明介质上打印彩色图像时的喷墨打印装置及打印方法。一般在玻璃等透明介质上打印图像时，先使用白色油墨在透明介质上打印彩色图像，然后彩色图像上覆盖白色油墨，观察者透过透明介质观察打印图像。如图6a所示，本发明的喷墨打印装置中的喷头底板611包括十个喷头，该十个喷头为同一型号的喷头，十个喷头分两行设置，所有喷头的喷孔排列方向与打印介质的运动方向平行，且所有喷头的排向一致，每色油墨均采用两个喷头打印。喷头9、10用于喷射白色（W）油墨，喷头1、2用于喷射青色（C）油墨，喷头3、4用于喷射品红色（M）油墨，喷头5、6用于喷射黄色（Y）油墨、喷头7、8用于喷射黑色（K）油墨，喷射白色（W）油墨的喷头9、10并排排列于喷墨打印装置的出纸端，喷射青色（C）油墨、品红色（M）油墨、黄色（Y）油墨、黑色（K）油墨的喷头并排排列于喷墨打印装置的进纸端，其中打印同一色彩色油墨的两个喷头喷孔首尾串接，即喷头1与喷头2的喷孔首尾串接、喷头3与喷头4的喷孔首尾串接、喷头5与喷头6的喷孔首尾串接，喷头7与喷头8的喷孔首尾串接。
如图6b所示，本发明中的喷射白色油墨的喷头9、10还可以插值排列，其喷射彩色油墨的喷头1-8的排列方式和图6a中一致。
喷墨打印时，喷射彩色油墨的喷头1-8先在透明打印介质打印彩色图像，UV灯固化装置71、72对打印图像进行固化，然后喷射白色油墨的喷头9、10在以固化的彩色图像上喷射白色油墨，观察者透过透明介质观察打印图像，其打印方法和实施例中的打印方法一致，喷射白色油墨的喷头9、10采用两遍打印方式，喷射彩色油墨的喷头1-8采用四遍打印方式。
实施例三
本实施例为用于在非白打印介质上打印彩色图像的又一喷墨打印装置及相应的打印方法，为保证白色油墨覆盖整个打印区域，可以插值排列或并排排列多个白墨喷头以增加打印区域白色油墨的浓度，提高打印图像的鲜艳度。如图7所示，本实施例中并排排列三个喷射白色油墨的喷头9、10、11，本实施例中喷头9、10、11也可以插值排列。根据实际需要也可以插值排列或并排排列四个或更多喷射白色油墨的喷头。其中喷射彩色油墨喷头1-8的排列方式与实施例一中喷射彩色油墨的喷头1-8的排列方式一致。
上述实施例中，根据实际打印需求可以使喷射涂层油墨的喷头喷射透明色油墨或者其他底色油墨，如灰色油墨。本发明的实施例中无论涂层油墨为什么颜色的油墨，其喷头排列方式和打印方法的原理与涂层油墨为白色油墨时的喷头排列方式和打印方法一致。
本发明通过将多个喷射涂层油墨的喷头插值排列或并排排列于一行中，喷射彩色油墨的喷头喷孔首尾串接排列于另一行中，保证涂层油墨覆盖整个打印区域的同时，大大缩短喷头底板的宽度，降低对UV灯固化装置宽度的要求，节约成本的同时也能提高喷墨打印小车工作的稳定性。
需要指出的是根据本发明的具体实施方式所做出的任何变形，均不脱离本发明的精神以及权利要求所记载的范围。

Claims (9)

  1. 一种喷墨打印装置，其特征在于，包括至少四个喷头，所有喷头为同一型号喷头，其中至少两个喷头用于喷射涂层油墨，其余喷头用于喷射彩色油墨，所述用于喷射涂层油墨的喷头排列于一行中，所述用于喷射彩色油墨的喷头并排排列于另一行中；所述用于喷射涂层油墨的喷头插值排列或并排排列；沿打印介质运动方向，所述用于喷射彩色油墨的喷头中喷射同一色油墨的喷头喷孔首尾串接，喷射不同色油墨的喷头并排排列。
  2. 如权利要求1所述的喷墨打印装置，其特征在于，所述涂层油墨为白色油墨。
  3. 如权利要求1所述的喷墨打印装置，其特征在于，所述涂层油墨为透明色油墨。
  4. 如权利要求1所述的喷墨打印装置，其特征在于，所述用于喷射涂层油墨的喷头数量与所述用于喷射同一色彩色油墨的喷头数量可以相同也可以不同。
  5. 如权利要求1所述的喷墨打印装置，其特征在于，所述用于喷射同一色彩色油墨喷头的数量相同。
  6. 一种喷墨打印方法，具体为，提供至少四个喷头，所有喷头为同一型号喷头，其中至少两个喷头用于喷射涂层油墨，其余喷头用于喷射彩色油墨；所述用于喷射涂层油墨的喷头与用于喷射彩色油墨的喷头分别排在两行中；所述用于喷射涂层油墨的喷头插值排列或并排排列；沿打印介质运动方向，所述用于喷射彩色油墨的喷头中喷射同一色油墨的喷头喷孔首尾串接，所述用于喷射彩色油墨的喷头中喷射不同色油墨的喷头并排排列，喷墨打印时，所述喷射涂层油墨的喷头采用N遍打印方式，所述喷射彩色油墨的喷头采用2N遍打印方式，其中N为大于0的自然数。
  7. 如权利要求6所述的喷墨打印方法，其特征在于，喷墨打印时，所述喷射涂层油墨的喷头采用两遍打印方式，所述喷射彩色油墨的喷头采用四遍打印方式。
  8. 如权利要求6所述的喷墨打印方法，其特征在于，所述涂层油墨为白色油墨。
  9. 如权利要求6所述的喷墨打印方法，其特征在于，所述涂层油墨为透明色油墨。
PCT/CN2011/077839 2011-08-01 2011-08-01 喷墨打印装置及其打印方法 WO2013016860A1 (zh)

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