METHOD FOR IMPROVING MECHANICAL ROBUSTNESS OF A COLOR PRINT

Abstract

A method for improving the abrasion resistance of a printed image, the image being processed digitally by a colour management system for a print process comprising a set of colorants, the colour management system transforming a colour of a part of the image into a colorant coverage for said part of the printed image, wherein a sum of coverage values for all colorants in the set of colorants is larger than a user-selectable threshold value. In a preferred embodiment the set of colorants includes a colorless, transparent colorant.

Claims

1. A method for improving the abrasion resistance of a printed image, that results from an image being processed digitally by a color management system for a print process comprising a set of colorants, the color management system transforming a color of a part of the image into a colorant coverage for said part of the printed image, wherein a sum of coverage values for all colorants in the set of colorants is larger than a user-selectable threshold value.

2. The method according to claim 1, wherein the set of colorants comprises a colorless, transparent colorant.

3. The method according to claim 1, wherein the print process is an ink jet process.

4. The method according to claim 3, wherein the colorant is a UV-curable ink.

5. A color management system, comprising a profiling module and a user interface for setting parameters to control a transformation of a color of a part of an image into a coverage value for said part of the image, the user interface comprising a field for setting a lower limit for a sum of the coverage values for all colorants.

6. A print system for printing an image on a substrate, the print system comprising a controller for processing digital image data into print instructions, the controller comprising a color management system according to claim 5.

7. A non-transitory computer readable medium storing computer executable instructions for applying the method according to claim 1.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The present invention will become more fully understood from the detailed description given herein below and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present invention, and wherein:

[0014] FIG. 1 is a flat bed print system wherein the invention is applicable; and

[0015] FIG. 2 is a user interface of a color management system according to the invention.

DETAILED DESCRIPTION OF EMBODIMENTS

[0016] The present invention will now be described with reference to the accompanying drawings, wherein the same or similar elements are identified with the same reference numeral.

[0017] FIG. 1 is a print system 5 comprising a workstation 8 and a print engine 4. The workstation 8 may be a personal computer or another device for preparing image data in print jobs for prints to be printed by the print system. This workstation has access to a network N, either wired or wireless, for receiving print jobs comprising image data from other image preparation devices (not shown). The workstation 8 is configured as a print controller that schedules the different print jobs and converts the image data into print data. This conversion comprises a color conversion from device independent colors to colors of the available colorants in the print engine 4. The available colorants are for example cyan (C), magenta (M), yellow (Y), black (K), white (W), varnish (V), light cyan (Ic), light magenta (Im), green (G) and orange (O). These print data are communicated to the print engine by a dedicated communication interface 6. Inside the print engine 4, an engine controller (not shown) organizes the print data into print swaths and controls the print engine to apply the colorants according to the print data.

[0018] The print engine 4 comprises a flat bed surface 1 for supporting a flat receiving medium. The height of the flat bed surface is adjustable to accommodate the thickness of the receiving medium, thus keeping a predetermined distance between the surface of the receiving medium and the print heads in the print head carriage 3. The print head carriage 3 is capable of moving across the flat bed in two directions, indicated in FIG. 1 as Z and X direction. Z is the scanning direction wherein the carriage reciprocates along gantry 7 to print a swath of ink drops that constitute the printed image, X is the sub-scanning direction wherein gantry 7 makes a stepwise movement at the time the gantry is reversing its reciprocating movement in the scanning direction Z. The movement of the gantry is guided by guide rails 2 at both sides of the flatbed.

[0019] FIG. 2 shows a user interface for a color management system according to the invention. The interface 10 shows two settings for the Total Area Coverage (TAC), which is the sum of the coverage values of the individual colorants. The individual values range from 0 to 1, so the sum is in the range of 0 to the number of colorants. In the present print system four colorants plus a colorless, transparent colorant is used. Both a minimum value 11 and a maximum value 12 are set in this interface. The range for the minimum value is 0 to 1, whereas the range for the maximum value is 1 to 4, in this embodiment. In known systems only a maximum is used, such that a colorants combination for a specific color is only acceptable if the TAC for this combination is lower than the selected value. In the present system also a minimum value 11 can be selected, such that an acceptable colorants combination has a TAC that is larger than the selected value. In normal print situations, the minimum value is 0, in order to obtain an area without any colorant coverage if a white color or a substrate color is specified in the image data. However, in special situations, such as a printed image for use under mechanically abrasive conditions, it is convenient to have a minimum TAC value that is larger than 0, preferably 1, such that all the substrate is covered with a full layer of colorant, which is in the present system a UV-curable ink.

[0020] The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the scope of the invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims.