Method and apparatus for determining and controlling inkjet printing drying time
AssigneeHewlett-Packard Company
InventorsJefferson P. Ward, Thomas W. Ruhe, Thomas E. McCue, Jr.
Life of this patent
Estimating the term…
Abstract
Print media drying time need not be set to an artificially high "worst case" drying time. Instead a reliable drying time is estimated based upon factors, such as temperature, humidity, media type, print quality and ink drop volume. When the estimated drying time is undesirably slow, the estimated and actual drying time is reduced by altering the ink composition of the image to be printed. One technique is to over-print or under-print with composite black rather than a true pigment black. Another technique is to deplete the black ink used throughout the image.
Claims24
A method for printing a print job spanning a plurality of media sheets, the print job including print commands, the method comprising the steps of:
- identifying a print job parameter for the print job;
- sensing ambient humidity;
- estimating a media sheet drying time from the identified print job parameter and sensed humidity;
- reducing the estimated drying time by changing a plurality of print commands of the print job to reduce black pigment ink used for the print job;
- printing to the media sheet using the changed plurality of print commands;
- waiting for a time period before resuming printing, wherein the time period is based on the reduced estimated drying time.
An apparatus for printing a print job spanning a plurality of media sheets, the print job including print commands, the apparatus comprising:
- means for identifying a print job parameter for the print job;
- a sensor which detects ambient humidity;
- means for estimating a media sheet drying time from the identified print job parameter and sensed humidity;
- a controller which reduces the estimated drying time by changing a plurality of print commands of the print job, wherein the print commands reduce black pigment ink used for the print job to achieve an adjusted drying time;
- a media handling system which moves the media sheet along a media path into a position to receive print;
- an inkjet pen which prints to the media sheet using the changed plurality of print commands, wherein the controller controls the media handling system to allow a time period before printing to another media sheet, wherein the time period is based on the adjusted drying time.
A method for printing a print job spanning a plurality of media sheets, the print job including print commands, the method comprising the steps of:
- identifying a print job parameter for the print job;
- sensing ambient humidity;
- determining an estimated drying time for a media sheet based upon the identified print job parameter and sensed humidity;
- comparing the estimated drying time to a threshold drying time;
- when the estimated drying time exceeds the threshold drying time, reducing the estimated drying time by changing a plurality of print commands for the media sheet to reduce black pigment ink used for the media sheet, and printing to the media sheet using the changed plurality of print commands;
- when the estimated drying time does not exceed the threshold drying time, printing to the media sheet without reducing the black pigment ink used for the media sheet;
- and
- waiting for a time period before resuming printing, wherein the time period is based on one of either the determined estimated drying time or the reduced estimated drying time.
Dependencies are inferred from the claim text.