It seems that WD 40 is mostly paraffins.
So it seems they should be good at making waterproof greases more liquid and so more easily removed. Then the WD40 removed from the cloth by detergent and water.
The good thing about WD40 is probably that it is easily available and being in an aerosol easy to apply indoors to furniture.
I’ll be thinking of using it in the future.
I have had a go at cleaning it today. I used the cleaning stuff they flogged me when I got the sofa.
It’s not entirely gone, but looks a lot better. I’ll give it another go tomorrow, and maybe try WD40.
From the picture it is not apparent at all.
If the picture is accurate then anyone not knowing it was there, would be hard pushed to notice it without prompting.
Fun fact; £1 billion to the first person who tells me what WD40 stands for. Google not allowed.
water displacement
War Department…they tried lots of different “recipes” and number 40 was approved by the WD.
BBC R4 ages ago but I can’t remember who it was said that.
If I’m correct I’ll post my bank details later so you can transfer the money!
Wikipedia says @cooper1203 is correct.
So, i won’t need to write out my bank detalis now.
we were both half right i didnt know what the 40 meant.
however i did miss read your answer and thought for a moment you had said war displacement 
You won.
Put up your details and @maoster will see you right. 
You’re all loonies and only halfway correct, so it’s only £500k each. Send me your card details and CVV and I’ll send it. My email is PrinceUmbongonigeria.org.
It was developed for NASA as a water displacement system and it was the 40th “recipe” that they presented to NASA before finally being approved.
As an aside it’s actually a wonder spray, it lubricates, it cleans (UPVC window frames a specialty) and some people with arthritis have claimed (with absolutely zero medical evidence) that if sprayed on affected joints it works wonders
Since it is a water displacer, would it be good at preventing tears when peeling onions I wonder? Quick squirt in the eyes?
Money to a charity please. RNIB.
umm if the prize was a billion your missing a few zero’s there…
Being serious though the story i read was that it was developed as a means to stop the outer metal shell of the atlas missile going rusty.
I have heard of people using it as a toilet cleaner to stop limescale build up i wouldnt try it in your kettle though
