Why is there so much lint from the new sheet and the new comfort

I changed my daughter's bedding to new sheet and new comforter (twin-sized).  After washing them, I dried them indoors until they were completely dry.
They both feel good.  But they produce so much lint (on the floor, to the dresser next to bed, etc.) every day.  This did not happen with the old ones.  I am wondering why.  And this has been three weeks already.  Because I did not use a dryer after washing?  Thx much,