This seems a good time to repeat my tie washing advice.  I always wash my recycled ties before using them, unless it is very clear that the tie was never used AND I don't expect to wash the finished product.  Many silk ties will bleed excess dye when wet, so I always add a bit of color fixative to the load when washing them.  I use Retayne, which I get at my local quilt shop, but there may be other products available.  I use a mild detergent similar to "Quilt Soap", but you can use any mild washing product.  I also use a liquid fabric softener, as it helps prevent static cling when I press later.