Why can't I put your paper cups or soup cups in the microwave?

Paper hot cups and soup cups are designed to hold hot drinks and food, but not to withstand the extreme heat of a microwave. At best, the glue at the seam can loosen and the cup will start to leak. At worst, the cups can even catch on fire! This is true for all paper cups, not just ours. We recommend microwaving in glass or ceramic containers labeled as microwave safe.