Silpat Hygiene

Any of you folks own a Silpat, or perhaps a knockoff?  I own a couple knockoffs.  The other day they were dirty, and I was also doing a load of laundry.  I wondered "Why can't I just throw this thing in with my dish towels and the like?"  It seemed to wash fine.  I just hung it up to dry.  I've done it again once since then, still with no apparent ill effects.  Have any of you folks tried this?  I wonder if they would tolerate small amounts of bleach in the wash?