How to send send cups a "print only in black ink" command?

Question

I try to get a HP Officejet Pro X476 to use only black ink to print plain text in document with colours.

In LibreOffice this is possible, I just have to click on "print text in black" what is an option in the printing dialog (colour section). But which option would that be if I want to tell this cups directly?

I have attached the current settings of my printer. In case I print directly to the queue I get a coloured text in colors, do I use libreoffice with the above mentioned settings, I get a result in black...

Is there a option to debug what cups received from libreoffice?

Thanks for any hint!

root@srv:~# lpoptions -d p1lp1 
copies=1 device-uri=socket://192.168.55.21:9100 finishings=3 job-hold-until=no-hold job-priority=50 job-sheets=none,none marker-change-time=0 number-up=1 ppd-timestamp=* printer-commands=ReportLevels printer-info='HP Officejet Pro X476dw MFP' printer-is-accepting-jobs=true **printer-is-colormanaged=true** printer-make-and-model='HP Officejet Pro X476-X576 MFP Postscript (recommended)' printer-state=3 printer-state-change-time=1448749443 printer-state-reasons=none printer-type=8425500 printer-uri-supported=ipp://localhost:631/printers/p1lp1

root@srv:~# lpoptions -d p1lp1 -l
PageSize/Media Size: Letter Legal Executive Statement FanFoldGermanLegal 3x5 4x6 5x7 5x8 *A4 A5 A6 B5 B6 Env3.5x5 4x6.Photo 8.5x13.3889 195x270mm 7.25x10.2361 7.75x10.75 Postcard DoublePostcardRotated Env10 EnvMonarch EnvISOB5 EnvC5 EnvC6 EnvDL EnvChou3 EnvChou4 Custom.WIDTHxHEIGHT
Duplex/Two-Sided: *None DuplexNoTumble DuplexTumble
InputSlot/Paper Feed: Auto Tray1 Tray2 *Tray3 Tray1_Man
HPOption_Tray3/Tray 3: *True False
HPPJLOutputMode/Print Quality: *GeneralOffice Professional Presentation MaximumDPI
HPPJLDryTime/Dry Time: *0 Medium Long
HPPJLSaturation/Saturation: -2 -1 *0 +1 +2
HPPJLInkBleed/Black Ink Spread: Least Less *Default
**HPPJLColorAsGray/Print Color as Gray**: False HighQuality * **BlackInkOnly**
HPRGBEmulation/RGB Color: HPRGBEmulationNone *sRGB PhotoSRGB Adobe VividSRGB

Answer 1

I found the solution:

The setting to print color as grey (from the ppd) is valid an is processed.

HPPJLColorAsGray/Print Color as Gray: False HighQuality * BlackInkOnly 

But the settings from the actual printout "overwrite" the default values (what makes sense to me) and in case color is in an document an this is printed with default values -- the colour ink is used. This behaviour can be controlled in the print dialogue generally. E.g. in libreoffice you can use an option "print text in black ink" this would result in real black text (not mixed as black from colors).

In LaTeX you can use \usepackage[monochrome]{xcolor} to force all text to black an so the use of the black ink.

Im my case I wanted to directly print to the print queue even though the default was set in the ppd to use BlackInkOnly it was not the case. After I added this option additionally as parameter to my print command it worked as I want it to be: color is printed in gray and only the black ink is used.

lpr  -P<printqueue> -o HPPJLColorAsGray=BlackInkOnly ...