how to get black silicon stain out of jeans?

my husband has stain the size of a 50p on his jeans that he got doing some DIY on the roof. All i know is it's black silicon kind of stuff and it hasn't come out in the wash. would appreciate any suggestions as otherwise they'll have to be binned. cheers

Public Comments

1. buy a new pair it is the only way
2. Try treacle.This is not a joke reply. "Lyles Golden Syrup" works for most stains of that nature. If you would rather pay more, go to your local chemist and bu some glycerol. Alternetively try anti-freeze for car radiators. They are all exceptionally good for getting grass stains out of white trousers (I know this from cricket) and should work with silicon based products.Wash about an hour after application.
3. I don't know exactly what he has on his jeans. I think it is probably a tar like sealer. If this is the case then I would recommend using a paint thinner to soak the area and blotting the stain. Try not to rub to much. Keep doing this until the stain becomes very faint. The last part of the stain should be removed by pouring a narrow stream of thinner from about 3-4 feet high directly onto the stain. Place a container outside or in a large sink and put it inside the jeans so that there is only one layer of denim and the thinner is caught when poured through the fabric. The pressure of the liquid hitting the fabric should free up the remaining stain.