He explained it in Kansas City. As he tried to describe this British product, the room's consensus is that the U.S. version of this is Elmer's School Glue. I've started doing this myself. I was using wax on my rough-turned bowls. Now, I just use a 50% diluted mix of Elmer's that I buy in gallon jugs (for very little on Amazon). It's easy and seems to seal well. Much less work than melting wax and burning the daylights out of myself.
The least messy way might be if you could get a surplus homogenizer that would pressurize the mixture of hot water and melted wax to about 2500 - 3500 PSI and force that through a tiny orifice then that would help to break the long molecular chains and attach water molecules to the wax molecules. OK, maybe not very practical for a DIY project. Another possible way would be to find a suitable surfactant. I can imagine this one getting out of hand in a hurry ... visualize putting bubble bath in a blender ... cancel that visualization ... not good.