Pitch meets Snowy

Pitch is that black sticky stuff that builds up on circular saw blades. Once coated with sticky pitch, the blade slows down from the friction and is liable to grab the work and hurl it at you. Kickback it's called, and it is scary. Trees, having about a billion years of evolution to perfect their biochemistry, can make some really tough stuff. Pitch defies paint thinner, alcohol and WD-40. However there is an answer
Snowy Color Safe Bleach, a powder, comes in cardboard boxes. "Contains sodium perborate, sodium carbonate and sodium silicates". Works like magic. Fill a cookie sheet with hot water, add a generous amount of Snowy, and submerge the blade in the mixture. Only takes a couple of minutes and the pitch softens up and comes off with a little scrubbing with an old tooth brush.
Makes a blade cut like new.