Chemical burns are not itchy at the moment of the incident. However, as these burns heal, they can get itchy. Resist yourself from scratching these, as doing so can damage the new tissue that is doing the repair. Moreso, the healing process slows down with intrusions like this, and can further lead to excessive scarring. It is best to leave the healing chemical burns on their own. You can apply a cold compress to it to keep the itch and inflammation at bay.