You’ve just been working on your car or in the garage and your hands a greasy and oily.
In these circumstances, ordinary soap doesn’t really cut it. Your options are to use one of the industrial hand cleaners available from hardware stores or automotive stores, or…wait for it…shaving cream.
I kid you not.
I’m not sure why it works so well, other than to say it has exactly the right HLB.
The HLB is a measure of the properties of a surfactant. Shaving cream only really has one job in life – to create foam. Inside the can there is essentially water with a surfactant. As it comes out the nozzle, it gets mixed with air to create foam.
And evidently, by a sheer coincidence, the HLB required to create foam is also very good at dissolving oil and grease.