Canon MP750 - mono printing

Hi - almost all the printing and copying on my Canon Pixma MP750 is
done in black and white, and yet the colour tanks continue to empty.
Can anyone advise why this happens??

We have a very low print and copy load (a few pages a week), and very
little of that involves colour (say, 5% of some of the documents). The
Printer Properties option in File>Print is set to Grayscale and the
screen shows Mono Printing on Plain Paper. Despite these settings and
usage, the colour tanks need to be replaced about half as often as the
black.

I would be grateful for any info on stopping this happening.

Many thanks in advance - Roy Simpson

All tanks will slowly drain due to cleaning cycles and evaporation. So it's
a question of degrees.

If you're selecting "plain paper" when printing, only the black tank is
used. If you select most other types of paper, the color tanks are used.


"RoyS" <roysim@btinternet.com> wrote in message
news:1177504030.815628.173950@r35g2000prh.googlegr oups.com...
> Hi - almost all the printing and copying on my Canon Pixma MP750 is
> done in black and white, and yet the colour tanks continue to empty.
> Can anyone advise why this happens??
>
> We have a very low print and copy load (a few pages a week), and very
> little of that involves colour (say, 5% of some of the documents). The
> Printer Properties option in File>Print is set to Grayscale and the
> screen shows Mono Printing on Plain Paper. Despite these settings and
> usage, the colour tanks need to be replaced about half as often as the
> black.
>
> I would be grateful for any info on stopping this happening.
>
> Many thanks in advance - Roy Simpson
>

"Dan G" <none@12345.org> wrote in message
news:7bidnYjP1JylArLbnZ2dnUVZ_gCdnZ2d@comcast.com. ..
> All tanks will slowly drain due to cleaning cycles and evaporation. So
> it's
> a question of degrees.
>
> If you're selecting "plain paper" when printing, only the black tank is
> used. If you select most other types of paper, the color tanks are used.
>
>
> "RoyS" <roysim@btinternet.com> wrote in message
> news:1177504030.815628.173950@r35g2000prh.googlegr oups.com...
>> Hi - almost all the printing and copying on my Canon Pixma MP750 is
>> done in black and white, and yet the colour tanks continue to empty.
>> Can anyone advise why this happens??
>>
>> We have a very low print and copy load (a few pages a week), and very
>> little of that involves colour (say, 5% of some of the documents). The
>> Printer Properties option in File>Print is set to Grayscale and the
>> screen shows Mono Printing on Plain Paper. Despite these settings and
>> usage, the colour tanks need to be replaced about half as often as the
>> black.
>>
>> I would be grateful for any info on stopping this happening.
>>
>> Many thanks in advance - Roy Simpson
>>
>
>
Color tanks are also used when printing in duplex mode.

Dan G, Burt - thanks for your replies. The problem occurs even tho' we
don't do duplex printing and plain paper is selected. It must be the
evaporation over time' altho' I have seen the suggestion that the
colours are also used to 'enhance' the black.

best wishes - Roy