So I was at work today printing out a spreadsheet (with the grid printing out also). Now keep in mind that I made the entire thing myself and know that black was the ONLY color used in it (until the bottom of the page where one cell is shaded with yellow, if that makes a difference). So anyways, when it had about the first quarter of a page done, it started pulling another piece of paper up, I firmly grasped said piece of paper and tried to hold it/pull it back. Well at that point the second piece was already pretty far and my pulling caused the whole feed mechanism to go haywire for a second. Since during this little tug of war it couldn’t properly advance the paper, I expected the printing for those couple of lines to be compacted (which they were), but what was odd, was that color showed up. There was a (black) horizantal line, that had a magenta line above it and a cyan line below it, and another place where one of the lines had a yellow line above it. Now I assume that the paper feeders are mechanically independent of the print heads, that is to say that the print heads don’t know if there’s a paper jam, and even if they did, should randomly start printing other colors. So the ONLY logical conclusion is that HP (oh, if you didn’t figure it out, it’s an HP printer, an inkjet to be slightly more specific) is stealing ink from me. It seems that they found that when printing black they can print small amounts of color within that black. If the amounts are small enough, no one notices, but the cartridges will run out quite a bit faster. (Actually I doubt HP is stealing ink from me, but I really did find it quite odd that color showed up, when no color should even have been involved.)
Your printer uses three colors to print black(yellow+cyan+magenta=black). When you see three disistinct colors as you did it is because the print head is printing out of alignment.
Sorry, no conspiracy
It depends. My printer has a separate black ink cartridge and this saves color ink. Depending on how you configure the printer it will print in different ways. It has settings for “photo”, “text”, “mixed”, etc. But my black head was not working for a while and I was using color ink all the time and it used it up like crazy.
I also have a black cartridge as well as a color cartridge. So I’d assume black is just black. The other thing I was thinking was that even if it was using multiple colors on the black part, when I jammed up thr printer all the colors still should have come out on the same line, since there woulnd’t have beem any paper advancememt between the colors. But this had magenta, black, cyan, and yellow all on different lines. Odd.
Maybe later I’ll try to repeat it and put a picture of it online.
I don’t think it prints in only black, unless you tell it to print in ‘mixed’, as sailor said. It would help to know what software and printer you’re using.
I doubt this is a subtle ploy by HP to sell you more ink, somehow, though of course I could be wrong. I think it’s just a lack of communication between printer-designer and software-designer.
'Tis true, most inkjet printers (even those with a black cartridge) print some color in with the black. I’ve read various excuses for this from manufacurers - including HP. Sometimes they do it because there’s a drying agent in the color ink that also makes the black dry faster. Sometimes its just because it was simpler to program a mix and not take special note of pitch black and turn off the colors in the rasterizer. And some times its all of the above, and that makes you buy color cartridges even though you’ve only printed in B/W - more cash in the till for the manufacturer.
If you are printing mixed (color and B/W) on one page, then there’s a good chance the programmer took the easy way and didn’t trap pure black passages - he mixes color in the whole page because there is some color in there somewhere - and management didn’t jump his ass for being lazy because it makes them money.
Ehh. You’ve got to make up for the low selling price of the hardware somehow. Not pretty, but true.
The print head uses different jets on each pass across the page. The colors are interleaved through the jets, so that a magenta line might come out on one pass, and then get cyan or yellow sprayed on the same line with the next pass - even though the paper has advanced.
refill kits. they have ink refill kits you can get. they are quite a bit cheaper then ink cateridges. you can get them for both color and black cateridges. meijers carries them i belive.
and stick it to the printer companies!!! 
What’s a “cateridge”?Sounds like a painful hospital procedure.
Yes, and if you don’t mind how the colors come out then that’s fine. My printer (with the proper cartridges and ink) comes so close to what my monitor shows that I can’t tell the difference by eye.
If all you want is “Oh, looky, colors!” then go right ahead with the aftermarket stuff - and don’t be surprised when the company that built your printer discontinues a model that no longer makes them money.
You should be able to force your printer driver to print in grayscale; that should stop the color from being used in your black text. But, of course, your yellow cell won’t come out yellow. Printer manufacturers say that adding color to “pure” black text makes the text crisper, kind of like anti-aliasing.
My first inkjet in 1994 or so had swappable cartridges, meaning I could use a black cartridge or a CYM cartridge, but not both at the same time. Black text rendered with the color cartridge always came out a yucky (and wet!) brown. Although this may have improved nowadays, I think you would definitely notice a quality decrease if black weren’t drawn with black ink, as you’re also effectively decreasing the dot-pitch.
Sorry, it sometimes even happens when you explicitly set “black only” in the printer driver control panel. There are reports from CT (a reliable computer magazine over here) that the magazine’s people have verified of color cartridges running out of ink after printing large quantities text using the “black only” settings. HP comes to mind as being one of the companies named whose printers did this.
I guess you could try removing the color cartridge, if your printer will run that way. My Cannon here at work will print in black without the color installed. I realize you have an HP but you could try it if it concerns you enough.
To borrow an ancient offset-printing term, printing four color black (black, plus cyan, magenta and yellow) is called “fat black” so named because it results in a black that’s blacker than just black ink alone, which sometimes looks more like dark gray.
Yes, it does suck up the color ink, and yes, in the end it’ll cost you more. For printing graphics, it really makes a difference in overall quality. For printing spreadsheets, well…
Controlling it is challenging, if even possible. How it all comes out depends on the interplay of the application, the printer driver, Windows’ color matching and how everything’s been configured: grayscale or not, draft, normal, best, photo quality, even the kind of paper selected - regular, photo or transparency. If you think trying to prevent printing fat black is vexing, try forcing it to get truly black on transparencies in an application that doesn’t comprehend transparencies. (been there and failed, oddly enough, with an HP inkjet)
I can’t understand the claims of producing sharper text. Black alone has no registration or alignment issues. Printing fat black requires everything to be perfectly aligned, or you’ll get colored fringes, which will only blur the test, rather than sharpen it.