In article ,
Scott writes:
On Tue, 23 Jan 2018 12:32:01 -0000 (UTC),
(Andrew Gabriel) wrote:

In article ,
TimW writes:
On 23/01/18 10:48, wrote:
I have pillowcases with unknown stains on, they look like maybe oil, with just slight darkening, but standard washing doesn't touch them. There's no way to find out what's on them. Any ideas as to how to proceed? It'll be at least a day before I can rewash them.


NT

bio detergent, heat and time by whatever method you choose.

+1, and definitely not an eco washing powder.

If cotton, a 60C or 90C wash, otherwise hottest the label allows.

I thought biological detergents worked best at low temperatures?

The enzymes only work up to about 40C, after which they're destroyed.
The detergent in the powder will work hotter.
So, a modern machine (last 35 years) should fill at no more than 40C
anyway, and for a hot wash, it will crank the temperature up in stages.
There are other reasons too not to dunk clothes directly in 60 or 90
degree washes, but to work up to that in stages - some dirt which
is removable at lower temps will cook on at higher temps and be more
difficult to remove.

I would tend to soak overnight in lukewarm biological detergent then
give it a hot wash the next day. I could be entirely wrong.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]