My husband had in his sweater a salad oil stain of 50x50cm. I thought the sweater was lost, but I have a booklet with old household tips. Here is that you have to wash the stain with alcohol and salt. I have this stain treated first by hand and then put in water with salt and alcohol after an hour just is machine washable. To my surprise, the entire stain is gone out. You'll never see it again.