EP2461295A1 - Colour printer module for a franking machine - Google Patents

Abstract

The method involves allowing an inkjet franking system (10) to print a franking mark i.e. postal imprint (18A), on a mailpiece (18) using three primary inks such as cyan, magenta, and yellow, where one of the primary inks is constituted by a postal ink such as postal blue for cyan and/or postal red for magenta. The franking system is provided with a print module that is formed from three or four ink reservoirs each containing the inks of different colors in order to perform three-color or four-color printing process using a cyan, magenta, and yellow model. An independent claim is also included for a print module formed of three ink reservoirs.

Description

Field of the invention

The present invention relates to the field of mail processing and more particularly that of franking machines or other envelope printers comprising a digital inkjet printing module.

Prior art

Today, inkjet printing is widespread for printing photos, office documents but it has also been used for ten years in the postal field for the printing of franking marks. In the latter case, the printing is then only monochrome of a specific color, called postage country color franking (fluorescent red for the USA and Canada, red 185U in Great Britain, blue postal for Germany and France for example) and it concerns both the brand of frankness itself as logos, advertising, images or messages that can accompany it.

Therefore, if the sender wishes that the graphic elements other than the franking mark are not printed with the color of the postal ink, but more classically with the black ink, it is necessary to add to the machine to frank an additional print head fed from a black ink tank in addition to that supplied by the color postal ink, as illustrated for example by the patent US6,079,327 .

However, some senders / users want these logos, advertisements, images or messages to be printed not only monochrome but also in color in order to hold the recipient's attention or simply to convey the image of their company. To satisfy this need, the franking machine must be able to meet the two printing constraints (postal and color).

Conventionally, the printing methods implemented in a color printer use the cyan (C), magenta (M), yellow (J) primary inks, to which black (N) is added to enhance the color contrast. In an inkjet printer, these colors come together to create the other colors present in the range. By playing on the combination of these four primary inks and on their percentage, we obtain all the printable colors in a certain colorimetric volume. Some higher-performance printers used for high-quality photo printing use up to 8 different primary inks (Cyan, Cyan light, Magenta, Magenta light, Yellow, Yellow light, Matt BlacK, BlacK glossy). This allows you to expand the range and print colors that can only be achieved with just four primary inks.

Unfortunately, the franking marks must meet the postal specifications as defined, for example, in the Universal Postal Union (UPU) Standard S44, particularly in terms of contrast and modulation for reading bar codes and, in practice it is very difficult to obtain satisfactory franking marks beyond a certain printing speed, typically 1m / s, with a combination of inks. In fact, errors in the positioning of ink drops from different heads disturb the re-reading of the bar codes, even though they are barely discernible to the naked eye. This is also true in the case of integrated tri- or quadric-chromatic printheads, comprising several rows of nozzles each corresponding to one of the primary inks, as used in office inkjet printers.

In addition, even with such a wide range of colors, it is not possible to obtain the fluorescent red necessary for the printing of franking marks in the USA or Canada. That is why the plaintiff proposed in the application US2006 / 023023 a multi-printhead structure enabling color printing at high postage stamp printing rates and in which the postage stamp required for printing the postage mark is associated with the conventional three or four inks prerequisites for the desired color printing for other graphic elements.

It is this same solution that was taken over by Pitney Bowes, which, less than a year ago, introduced on the market a postage meter (Connect + ™ 3000 model) able not only to print the brand of postage to its specific postal color but also to include logos, advertising, images and messages printed in four-color process. To do this, this franking machine is provided with two printing modules, one classically allowing the monochrome printing of the franking mark and the other four-color printing of other printed graphic elements.

This solution responds well to the problem posed in particular as to the speed of printing. Unfortunately, it is very expensive because of the addition of the color printing module in addition to the standard postal printing module, and this addition also increases the overall length of the machine in which this module is incorporated and a significant change of its architecture.

Definition and object of the invention

Also, the present invention aims to provide a printing method for a color franking machine whose cost is comparable to that of a monochrome machine (that is to say, only printing with an ink postal color), without noticeable reduction in printing speed. An object of the invention is also to provide a printing module that can be mounted in the current franking machine architectures and therefore without requiring significant changes in its hardware configuration. Another object of the invention is to provide a franking machine using the same set of primary inks and thus can be used both in countries requiring a red postal ink than in those that require a blue mailing ink .

These objects are achieved by a color printing system for franking system for printing a postage mark on a mail piece from at least the three primary inks Cyan, Magenta and Yellow, characterized in that at least one of said Cyan or Magenta primary inks is made of a similar color postal ink, namely postal blue for Cyan and / or postal red for Magenta.

More particularly, this method in which a franking system comprises a printing module fed by three or four ink tanks each having a different color ink to provide a CMYK or CMYK printing or tri-color printing is characterized in that, to provide printing of said postage mark by means of a postal ink, the Cyan color ink tank is replaced by a postal blue postal ink tank and / or the reservoir Magenta ink is replaced by a 185U red ink or fluorescent red ink tank.

Thus, it becomes possible, while preserving the original architecture of the franking machine, to proceed to the printing of the franking mark and the graphic elements which accompany it with the same module of impression and without penalizing its printing speed.

In order to increase the contrast, said postage mark can be printed with a combination of postage and black ink. In order to obtain, once printed, the colorimetric components required by the postal specifications, said postage meter may be printed with a combination of a postal ink and at least one of said remaining inks.

According to the envisaged embodiment, said mail item further comprising graphic elements or identification of the sender or third parties associated with said franking mark, said elements can be printed from a single ink other than that which has made it possible to print said franking mark or else in a color obtained from at least two inks.

The invention also relates to a franking machine or an envelope printer comprising a printing module fed by at least three ink tanks, each having a different color ink, of which at least one postal ink and capable of enabling the setting in. of the aforementioned postal ink color printing method.

Brief description of the drawings

• . la figure 1 est une vue schématique partielle d'une machine à affranchir à jet d'encre avec son module d'impression conforme à l'invention, et les figures 2 et 3 illustrent différentes gammes colorimétriques obtenues respectivement avec des encres ou des types de papier différents.

Other characteristics and advantages of the present invention will emerge more clearly from the following description, given by way of non-limiting indication, with reference to the appended drawings, in which:

• . the figure 1 is a partial schematic view of an inkjet franking machine with its printing module according to the invention, and the Figures 2 and 3 illustrate different color ranges obtained respectively with different inks or paper types.

Detailed description of a preferred embodiment

The figure 1 shows in partial diagrammatic view an inkjet franking machine 10 with its printing head 12 overhanging a guide plate 14 on which are transported, in a longitudinal direction D of displacement and taped against a referencing wall 16 These mail items are transported, as is known, by rollers (only the counter-rollers 20A, 20B are shown above the guide plate 14 just upstream and downstream of the printhead 12 and defining between them a minimum printing length for mail items) or transport belts of the franking machine, so as to pass under the print head and thus allow the printing of a 18A postmark on each of these mail items. Of course, as in any franking machine, control circuits (not shown) are provided in its base to ensure its operation and in particular the rotation of the transport rollers according to the position of the mail items through the machine picked up by different sensors (not shown).

The print head 12 comprises four ink tanks 12C, 12M, 12Y, 12K each associated with means for ejecting this ink (typically one or two rows of ink jet nozzles) and is controlled by a set electronic circuits conventionally comprising a microprocessor or microcontroller 22, a memory 24 and a control circuit (driver 26). The control circuit provides control of the ink ejection nozzles of the print head under the control of the microprocessor and according to a control program stored in the memory. The control circuit may or may not be integrated with the print head while the microprocessor and its memory are advantageously integrated into the base of the franking machine to which the print head is connected, and of which they can constitute a part control circuits.

According to the invention, the ink of the reservoir 12C and the ink of the reservoir 12M comprising, in the context of a four-color process according to the CMYK model, respectively a Cyan ink and a Magenta ink are replaced by the specific postal inks, namely the postal blue in place of the Cyan and the red postal, red 185U or fluorescent red (depending on the country of installation of the machine), instead of the Magenta. Thus, the width of the printing module is not increased due to the presence of a second head and the printing speed, at least in the case of printing the only franking mark, does not increase. is not reduced, this impression (and in particular that of its 2D barcode) with the postal ink being made from the single row of nozzles associated with the reservoir filled with this ink, as in the prior art.

In addition, the use of such a standard four-color print head can preserve a space of 125 mm existing to date between transport rollers framing this print head in the current printing modules of franking machines authorizing the printing of mail items in the "postcard" format and thus avoiding any structural modification of these modules. Conversely, the use of an additional module, as proposed in the prior art mentioned in the preamble, or simply the use of a single additional ink causes a significant increase in costs and the size of the machine.

As for the other graphic elements 18B, in particular identification of the sender (logos, advertising, images for example) or third parties (donation call messages for example) associated with the postage mark 18A, so that surprisingly, the inventor found that the substitution of the two primary inks by the specific postal inks made it possible to obtain a perfectly acceptable rendering for the desired use, namely the printing of mail items. This result is obtained without any colorimetric compensation. The table below compares the CIE LAB components of the colors obtained under the D50 illuminant, on solid colors made with primary inks of the CMYK (Cyan Magenta Yellow Black) model, and postal blue and fluorescent red postal inks. Color / component The at* b * cyan 60 -26 -44 Postal Blue 60 -16 -41 Magenta 56 61 -1 Fluorescent red 64 51 18

Even if acceptable results are obtained without color compensation, the color control program stored in the memory 24 can be adapted to take account of this substitution of the primary inks, as shown by the example of FIG. figure 2 wherein a first set of primary inks has been replaced by a second set of similar color inks. By similar color is meant a color having the same color base. For example, Cyan, which is also called light blue or sky blue, is similar to postal blue which has the same blue base and Magenta also called fuchsia red or purplish red is similar to fluorescent red or 185U red which both have the same base red.

Indeed, the figure 2 shows the colorimetric range obtained with the primary inks of the first set (in solid lines) and that with the primary inks of the second set (in dashed lines), both projected on the a * b * plane in the CIE LAB space, which is a uniform color space representing all the colors perceived by the standard human eye. It can be noted that the two curves do not overlap, which indicates that some colors printable with the first game can not be with the second. Moreover, without color compensation, a color printed with the same proportions of primary inks will be perceived differently with the first or the second set.

In order to obtain a color reproduction close to the first set in the printable range, different methods can be applied. These well known methods will not be the subject of a detailed description and only their principle will be recalled. Thus, the adjustment of the color profile consists in modifying the proportions of primary inks of each color to obtain an equivalent rendering. The method of clipping is to reduce the non-printable colors to the border of the curve corresponding to the second set. Compression is used to distribute the distortion caused by the differences in inks throughout the range, compression being used to compensate for significant distortions while respecting the perception of color deviations.

It should be noted that the printing speed may vary according to the expected quality of the graphic elements or identification to be printed. Thus, if only postal ink is used, this speed will not differ from that of a traditional printing module containing only a postal ink. It will be the same if, in addition to the postal ink, these printed elements in addition to the franking mark only require the independent use (without mixing) of one or more of the other three inks of the head (logo in yellow and black message for example), the printing of the three colors (yellow, black and blue postal for example) being made indeed then at the same speed.

When an element to be printed requires the combination of at least two inks (for example an orange logo requiring the combination of red and yellow), the printing speed can be maintained if the quality obtained is sufficient, or reduced to obtain better print quality and especially better contrast.

Note that it is also possible to combine the postal ink and the black ink to increase the contrast of the bar codes included in the franking mark. This may be desirable on some particularly porous paper envelopes. We can then choose a print mode at high speed or reduced speed depending on the desired results.

In general, it is possible to combine the postal ink with one or more of the other primary inks to compensate for the paper-related defects of the envelopes, in particular to obtain the colorimetric components required by the postal specifications. Indeed, as shown in figure 3 which illustrates the color ranges obtained with the same set of primary inks on three different types of paper, depending on the type of paper, the saturated colors can quickly be outside the capabilities of the system. For better rendering, appropriate compensation for each type of paper is therefore desirable by resorting to various known compensation methods, including those mentioned above.

It will also be appreciated that if reference has previously been made to a print head in which the Cyan and Magenta inks have been replaced by similar postal inks, it is obvious that it can also be envisaged that only one of these two ink is replaced by a similar postal ink, the Cyan by the postal blue or the Magenta by the postal red whether it is the fluorescent red or the red 185U (this will be particularly the case when the machine is intended to be installed on one type of market).

Finally, it will be appreciated that while the foregoing description refers to a process and four-color printing modules of franking machines, the same principle of substituting a primary ink with a similar postal ink can be applied to a method and tri-chromic printing modules according to the CMY model, or to modules for printing envelopes printers comprising for example more than four primary inks, depending on the cost and size of the printing system. postage sought.

Claims (13)

A color printing system for a franking system (10) for printing a franking mark (18A) on a mail piece (18) from at least the three primary inks, Cyan, Magenta, and Yellow, characterized in that at least one of said Cyan or Magenta primary inks is made of a similar color postal ink, namely postal blue for Cyan and / or postal red for Magenta. A color printing method according to claim 1 wherein said franking system (10) comprises a print module (12) fed by three or four ink tanks (12C, 12M, 12Y, 12K) each having an ink of different colors to provide CMYK or CMYK printing in tri-color or four-color process, characterized in that , to ensure the printing of said postage mark by means of postal ink, the Cyan color ink tank is replaced by a postal blue postal ink tank and / or the Magenta color ink tank is replaced by a 185U red ink or fluorescent red ink tank. A color printing method according to claim 2, characterized in that said print module is powered by three ink tanks (12C, 12M, 12Y) each having a different color ink for trichromatic printing according to a pattern CMY and in that the Cyan color ink tank is replaced by a postal blue color postal ink tank or the Magenta color ink tank is replaced by a red 185U or red postal ink tank fluorescent. A color printing method according to claim 2, characterized in that said print module is powered by three ink tanks (12C, 12M, 12Y) each having a different color ink for trichromatic printing according to a pattern CMY and in that the Cyan color ink tank is replaced by a postage blue postal color ink tank and the Magenta color ink tank is replaced by a red 185U or red postal ink tank fluorescent. A color printing method according to claim 2, characterized in that said print module is powered by four ink tanks (12C, 12M, 12Y, 12K) each having a different color ink to provide four-color printing according to a CMYK model and in that the Cyan color ink tank is replaced by a postage blue postal ink tank or the Magenta color ink tank is replaced by a 185U red ink post or fluorescent red. A color printing method according to claim 2, characterized in that said print module is powered by four ink tanks (12C, 12M, 12Y, 12K) each having a different color ink to provide four-color printing according to a CMYK model and in that the Cyan color ink tank is replaced by a postage blue postal ink tank and the Magenta color ink tank is replaced by a 185U red ink post or fluorescent red. A color printing method according to claim 5 or claim 6, characterized in that said postage mark is printed with a combination of a post-ink and black ink to increase the contrast. A color printing method according to claim 2, characterized in that said postage mark is printed with a combination of a postage ink and at least one of said remaining inks to obtain, once printed, the colorimetric components required by postal specifications. A color printing method according to claim 2, characterized in that , said mail item further comprising graphic elements (18B) or identification of the sender or third parties associated with said franking mark, said elements are printed from a single ink other than that which has made it possible to print the said franking mark. A color printing method according to claim 2, characterized in that , said mail item further comprising graphic elements (18B) or identification of the sender or third parties associated with said franking mark, said elements are printed in a color obtained from at least two inks. Print module powered by at least three ink tanks (12C, 12M, 12Y, 12K) each having a different color ink, at least one of which is a postal ink and capable of enabling the color printing process to be carried out according to any of claims 1 to 10. A postage meter having a print module according to claim 11. An envelope printer having a print module according to claim 11.

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