This invention relates to printing images on continuous-web receivers.
Color and other multi-channel images can be printed using ink jet printers, multicolor transferable toner printers, heat sensitive coated paper printers, thermal dye transfer printers, and other types of printers. Many mass-market retail establishments have user-friendly kiosks at which shoppers make color prints. Because the kiosks use large amounts of paper, the images can be printed on a continuous web of paper, often supplied in roll form and fed from a feed roll to the printhead that applies the image to the receiver. The images are later separated from each other and from the web by a suitable cutter or knife.
It is desirable when roll-feeding to pull the web past the printhead. This provides positive control of the web as it passes the printhead. In various schemes, the printhead forms part of the pulling apparatus, as in U.S. Pat. No. 5,441,353 to Kim. In other schemes, a separate pulling mechanism beyond the printhead is used, as in U.S. Pat. No. 5,021,804 to Nozawa et al. However, printing technologies such as inkjet printing use non-contact printheads, so the printhead cannot form part of the pulling apparatus. Moreover, using a pulling mechanism downstream of the printhead results in the receiver between the printhead and the pulling mechanism being unprinted and discarded, increasing waste and print cost.
Other schemes push the web past the printhead. Examples of such schemes are JP Publication No. H05-147284 (1993) by Kikumura et al. and JP Publication No. 2004-217342 by Iemura et al. However, these schemes do not provide positive control of the receiver until it engages a pulling member sometime after printing begins. This can result in variations in the spacing between the receiver and a non-contact printhead in the leading portion of the image, changing image attributes. These changes can produce a visibly-objectionable difference between the portion of the image pushed past the printhead and the portion pulled past. Pushing the web past the printhead over its entire length exacerbates these problems and can lead to receiver buckle, possibly contacting a non-contact printhead and damaging it (a “head strike”).
There is a continuing need, therefore, for a way of printing images on a continuous web with reduced waste of paper while maintaining consistent image quality.
According to an aspect of the present invention, there is provided apparatus for printing a multi-channel image on a web receiver, comprising:
a) a plurality of printing modules arranged in sequence along a feed path of the receiver and spaced apart from the feed path, each adapted to produce on the receiver a separation image corresponding to one channel of the multi-channel image;
b) a movable transport for the web receiver, the transport including a take-up roll around which the receiver is entrained and a cutter arranged downstream of the take-up roll for selectively cutting the web receiver, wherein:
c) a controller adapted to perform the following steps in order:
According to another aspect of the present invention, there is provided a method of producing a print of a multi-channel image on a web receiver, comprising:
entraining the web receiver around a take-up roll on a transport;
traversing the transport past a plurality of non-contact printing modules and depositing respective separation images on the receiver by activating the printing modules as they are brought into operative association with the receiver on the transport, so that a first portion of the image is printed; and
drawing the receiver past the printing modules using the take-up roll and activating the printing modules to deposit respective separation images on the receiver, so that a second portion of the image is printed.
According to another aspect of the present invention, there is provided a method of producing a print of a multi-channel image on a web receiver, comprising:
entraining the web receiver around a take-up roll on a transport;
traversing the transport past a plurality of non-contact printing modules and depositing respective separation images on the receiver by activating the printing modules as they are brought into operative association with the receiver on the transport, so that a first portion of the image is printed;
drawing the receiver past the printing modules using the take-up roll and activating the printing modules to deposit respective separation images on the receiver, so that a second portion of the image is printed, wherein a selected one of the printing modules deposits a first-layer separation image on a selected area of the receiver in the first or second portion;
repositioning the receiver by returning the transport or rewinding the receiver, or both, so that the selected area of the receiver is brought into operative association with the selected printing module; and
moving the receiver by traversing the transport or drawing the receiver, or both, while activating the selected printing module to deposit a second-layer separation image on the selected area of the receiver.
An advantage of this invention is that it provides reduced waste of receiver material in a non-contact, continuous-web printer. It maintains positive tension on the paper during printing, improving image quality. It is not limited in the total length of sheet that can be printed, and it is not limited to certain predetermined sizes of cut sheet. The receiver only moves in a single direction during printing, which can improve throughput. The movable transport can overcome the inertia of the supply of web receiver, permitting the take-up roll to be driven by a smaller, more responsive motor, and permitting the take-up roll to have a lower diameter than would be required if the take-up roll had to overcome the web inertia. Using a smaller-diameter take-up roll reduces the amount of receiver wasted as a leader before the image. In embodiments using arcuate transports with concentric supply rolls, the device is more compact than prior-art systems with supply rolls arranged ahead of the printing modules. Unlike prior schemes, the amount of leader in the present invention is independent of the number of stations. This is particularly useful for additive-fabrication schemes, which can have tens of stations for jetting different components.
The above and other objects, features, and advantages of the present invention will become more apparent when taken in conjunction with the following description and drawings wherein identical reference numerals have been used, where possible, to designate identical features that are common to the figures, and wherein:
The attached drawings are for purposes of illustration and are not necessarily to scale.
In the following description, some embodiments will be described in terms that would ordinarily be implemented as software programs. Those skilled in the art will readily recognize that the equivalent of such software can also be constructed in hardware. Because image manipulation algorithms and systems are well known, the present description will be directed in particular to algorithms and systems forming part of, or cooperating more directly with, systems and methods described herein. Other aspects of such algorithms and systems, and hardware or software for producing and otherwise processing the image signals involved therewith, not specifically shown or described herein, are selected from such systems, algorithms, components, and elements known in the art. Given the systems and methods as described herein, software not specifically shown, suggested, or described herein that is useful for implementation of any embodiment is conventional and within the ordinary skill in such arts.
A computer program product can include one or more storage media, for example; magnetic storage media such as magnetic disk (such as a floppy disk) or magnetic tape; optical storage media such as optical disk, optical tape, or machine readable bar code; solid-state electronic storage devices such as random access memory (RAM), or read-only memory (ROM); or any other physical device or media employed to store a computer program having instructions for controlling one or more computers to practice the method(s) according various embodiment(s).
In the example shown in
In fluid communication with each nozzle array 120, 130 is a corresponding ink delivery pathway 122, 132. Ink delivery pathway 122 is in fluid communication with the first nozzle array 120, and ink delivery pathway 132 is in fluid communication with the second nozzle array 130. Portions of ink delivery pathways 122 and 132 are shown in
Not shown in
(Y), magenta (M), cyan (C), and black (K) image data, each image channel is printed separately using a respective nozzle array. Other colors, such as orange (Or), green (G), and transparent protectant (P) can be used in producing prints. As used herein, a “multi-channel image” is data defining respective patterns of a plurality of respective inks to be deposited on a receiver. This can be a conventional multi-color photograph or line-art image, or a mask set for a device to be fabricated by printing with additive-fabrication materials or etchants.
In embodiments, including those using printing technologies other than inkjet, each printing module 220c, 220m, 220y, 220k produces on the receiver 210, or causes to be produced on the receiver 210, a separation image corresponding to one channel (e.g., C, M, Y, or K) of the multi-channel image to be printed. The printing modules 220c, 220m, 220y, 220k produce the images without coming into mechanical contact with the receiver. That is, the receiver 210 and the printing modules 220c, 220m, 220y, 220k are spaced apart during normal operation, although they can come into contact if the receiver 210 buckles or cockles severely. Not all printing modules are necessarily used for each image.
Cutter 320 selectively cuts web receiver 210 to form printed sheets 315. Cutter 320 can include one or more knives, rotary cutting blades, or automatic scissors or shears. Cutter 320 is arranged downstream of take-up roll 214 in the direction of travel of receiver 210.
Transport 305 is a movable transport for web receiver 210. Transport 305 includes optional feed roll 310, supply roll 212, optional supply tensioner 222, receiver 210, take-up roll 214, take-up tensioner 224, and cutter 320. Transport 305 also includes mounting hardware (not shown) to hold these components in position with respect to each other so that all components of transport 305 can move past printheads 220c, 220m, 220y, 220k together. Transport 305 can be moved by a linear slide or driven belt. The movement of transport 305, and the movement of receiver 210 past supply roll 212 and take-up roll 214, causes receiver 210 to move in feed path 240. Printing modules 220c, 220m, 220y, and 220k are arranged in sequence along feed path 240, and are spaced apart from feed path 240. In various embodiments, transport 305 is curved, or rotates (e.g., using a servo) rather than, or in addition to, translating.
In alternative embodiments, a collection roll (not shown) is used instead of cutter 320. This permits roll-to-roll printing with reduced leader waste. In various embodiments, the collection roll is unwound into a second printing unit having a plurality of print modules to print images on the back side of receiver 210. Alternatively, the collection roll can be removed from the printer and installed as feed roll 310 in the same printer or a different printer to produce backside prints. In these embodiments, the roll unwinds counterclockwise after installation as feed roll 310, since it is wound onto the collection roll clockwise (or, in general, unwinds in the opposite direction of winding).
In still other embodiments, cutter 320 is a perforator, e.g., a full-width die punch or a wheel cutter with spikes that traverses the width of receiver 210. In these embodiments, image content can be printed on receiver 210 up to the perforation on both sides. This reduces the length of the leader to the width of the perforation line, generally <0.5 mm. This provides printing with reduced leader, with reduced probability of bursting the perforations as can happen in a roll-to-roll process. Moreover, these embodiments provide prints one at a time, which is particularly useful in a kiosk. Mounting the perforator on transport 305 permits custom- or variable-length prints, as opposed to the fixed-length prints of pre-perforated receiver stock.
Transport 405 includes platen 410, but does not include supply roll 212, optional supply tensioner 214, or optional feed roll 310. Receiver 210 can bend as it reaches platen 410 (as shown), optionally over a roller or ski, or not. In various embodiments, platen 410 is curved to cause receiver 210 to follow a curved path, as will be discussed further below.
Transport drive 406 is represented graphically here for clarity; similar drives are present in other embodiments described herein. Transport drive 406 can include a ball screw, linear slide, piezoelectric actuator, servomotor, or other component providing linear or rotational motion. Controller 486 is also shown here; similar controllers are present in other embodiments described herein. Controller 486 is a CPU, PLD, PAL, PLA, microcontroller, FPGA, or other firmware or software device adapted to control the components of the printer.
Controller 486 is adapted to cause transport 405 to move past printing modules 220c, 220m, 220y, 220k to print a portion of the image, and to cause take-up roll 214 to draw receiver 210 across transport 405 (here, platen 410 specifically) to print the remainder of the image. This will be shown with reference to
By “traverse from the leading printing module to the trailing printing module,” it is meant that transport 305 moves so that receiver 210 is successively brought into operative arrangement with each printing module 220c, 220m, 220y, 220k. In
Controller 486 (
Leader 510 is a portion of receiver 210 that is not printed since it is engaged with take-up roll 214. Leader 510 cannot be brought into operative arrangement with any printing module (e.g., 220c). Leader 510 will be discussed further below. Various embodiments advantageously provide smaller leaders than prior schemes, reducing waste.
In various embodiments, controller 486 (
In various embodiments, controller 486 (
In one example, an inkjet press operating at a nominal web velocity of 200 m/min=131″/s and 300 dpi, each pixel passes a fixed point in 25.4 μs. Therefore, printing modules 220c, 220m, 220y, 220k each jet one line every 25.4 μs. It is desirable to move each dot no more than half a pixel from its intended position, so the pixel time is constant ±12.7 μs. Therefore, the speed of a given point on receiver 210 should be maintained between 133 m/min (25.4+12.7 μs) and 300 m/min (25.4-12.7 μs). This is “constant” as used above. In other embodiments, each dot moves no more than one-quarter of a pixel, here, ±6.35 μs.
Referring back to
In step 905, the web receiver is entrained around a take-up roll on a transport. Step 905 is followed by step 910.
In step 910, the transport is traversed past a plurality of non-contact printing modules. While the transport traverses, respective separation images are deposited on the receiver by activating the printing modules as they are brought into operative association with the receiver on the transport, so that a first portion of the image is printed. An example of this was shown in
In step 915, the receiver is drawn past the printing modules using the take-up roll and the printing modules are activated, so that a second portion of the image is printed. An example of this was shown in
In optional step 920, the printed portion is cut from the web receiver using a cutter downstream of the take-up roll in the feed path of the web receiver. An example of this was shown in
In optional step 925, the transport is returned to its initial position after printing the second portion of the image. The web receiver remains entrained around the take-up roll, so after the transport traverses back over its path, it is in position to print the next image. Step 925 is followed by step 910. The transport can also return to its initial position so that additional ink can be deposited on the receiver. This permits depositing ink layers in an order different from the physical order of the printing modules along the receiver. This also provides drying time while the transport traverses back.
In step 1010, the web receiver is entrained around a take-up roll on a transport. Step 1010 is followed by step 1020.
In step 1020, the transport is traversed past a plurality of non-contact printing modules. Respective separation images are deposited on the receiver by activating the printing modules as they are brought into operative association with the receiver on the transport. In this way, a first portion of the image is printed. Step 1020 is followed by step 1030.
In step 1030, the receiver is drawn past the printing modules using the take-up roll. The printing modules are activated to deposit respective separation images on the receiver, so that a second portion of the image is printed.
During printing of the first or second portions, a selected one of the printing modules deposits a first-layer separation image on a selected area of the receiver in the first or second portion. The selected area can also be divided between the first and second portions. Step 1030 is followed by step 1040.
In step 1040, the receiver is repositioned by returning the transport or rewinding the receiver, or both. The receiver is repositioned so that the selected area of the receiver is brought back into operative association with the selected printing module. In various embodiments, the receiver is rewound until only the leader is entrained around the take-up roll, then the transport is traversed back. Step 1040 is followed by step 1050.
In step 1050, the receiver is moved by traversing the transport or drawing the receiver, or both, as appropriate for the amount of repositioning performed. The selected printing module is activated while the receiver moves, and deposits a second-layer separation image on the selected area of the receiver.
This method is particularly useful in microelectronics fabrication. Devices such as solar panels can use 50 materials or more. Moreover, substrates for microelectronic devices can be very expensive. Substrates can include patterned glass and mono-crystalline silicon. Reducing leader waste is particularly useful with expensive substrates.
The invention is inclusive of combinations of the embodiments described herein. References to “a particular embodiment” and the like refer to features that are present in at least one embodiment of the invention. Separate references to “an embodiment” or “particular embodiments” or the like do not necessarily refer to the same embodiment or embodiments; however, such embodiments are not mutually exclusive, unless so indicated or as are readily apparent to one of skill in the art. The use of singular or plural in referring to the “method” or “methods” and the like is not limiting. The word “or” is used in this disclosure in a non-exclusive sense, unless otherwise explicitly noted.
The invention has been described in detail with particular reference to certain preferred embodiments thereof, but it will be understood that variations, combinations, and modifications can be effected by a person of ordinary skill in the art within the spirit and scope of the invention.
Number | Name | Date | Kind |
---|---|---|---|
5021804 | Nozawa et al. | Jun 1991 | A |
5441353 | Kim | Aug 1995 | A |
6109745 | Wen | Aug 2000 | A |
7250959 | Cloutier et al. | Jul 2007 | B2 |
7350902 | Dietl et al. | Apr 2008 | B2 |
7507046 | Ehmann | Mar 2009 | B2 |
20020130909 | Wojcik | Sep 2002 | A1 |
20050093959 | Kitamura | May 2005 | A1 |
Number | Date | Country |
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H05-147284 | Jun 1993 | JP |
2004-217342 | Aug 2004 | JP |
Number | Date | Country | |
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20120274694 A1 | Nov 2012 | US |