Canon Pixma MP620

[stratman]

If you look at the bottom of your print head you will see something like the following:

The longer and thinner set of nozzles on the right hand side is where the pigment ink exits the print head. The wider but shorter set of nozzles on the left hand side is where the dye-based CYMK ink exits. Since the pigment black are about twice as long as the CYMK nozzles, it takes one half the passes of the print head on the paper to print the page if just using pigment black such as for black text only printing on Plain Paper setting.

Matte setting uses only the CYMK inks, even for black text only printing, and therefore takes twice as many passes of the print head to cover the paper. Hence, Matte setting will take much longer to print the same black text than when set to Plain Paper.

 

[The Hat]

@barfl2, If you print your text using this method, the printer has to use all of the dye inks to form a single letter in each word, but the pigment black can form more that one letter at a time, so it’s a lot faster at covering the same area of paper, the pic below shows just how much longer the pigment head is to the colour ones.



When you’re using the Matte setting the letters are made up of hundreds of individual coloured dots, but the Pigment black can use far less dots to do the same job because the black dots are much bigger than the colour dots are.
Looks like @stratman was a bit quicker with his excellent explanation..

 

[stratman]

@The Hat your explanation adds details I did not even consider. Sort of a refiller's take on "it's not the size of the magician's wand but how he uses his wand".

 

[PeterBJ]

It seems it is much more complicated. The number of print head passes depends on both the quality and media settings, using other media setting than plain paper increases the number of print head passes. So the printing speed on other media than plain paper is much lower than and not only half that for pigment black only on plain paper. See this clip from the iP5200 service manual; click to enlarge:

 

[stratman]

@PeterBJ - nice!

The print head works much harder than most would suspect. Inkjet printers are amazing inventions.