Dye for beard

I used to have a goatee which I loved until it went grey. I tried dying with Just for Men and was happy with the result colourwise. But after a few uses my face became itchy and irritated. (To explain - a goatee is necessarily short; to stop the percentage of grey being noticable it was necessary to dye about twice a week).

I`ve tried other products but they all seem to have this same chemical that irritates my face. I`ve reluctantly shaved off my beard but but photographs tell me how much better I looked with it. Any suggestion what chemical may be causing this reaction and whether there are any products without it?