Microfiber

The majority of modern diaper inserts contain a popular synthetic fabric, microfiber.  Why?  Because microfiber has been engineered to be one of the most soft and absorbent fabrics.  It also quickly absorbs moisture, instead of causing urine to bead off and lead to leaks, like can occur with some more natural fabrics, like hemp and some cottons.  Considering the volume of wetness it can contain, it is quite thin and makes for a trim-looking diaper.  All this sounds great, but microfiber isn't all it's cracked up to be.

Microfiber is pretty crummy when it comes to holding wetness under compression.  What little one doesn't get held on mama's hip and doesn't plop down on the floor multiple times an hour?  That's compression.  Unless you are doing hourly diaper changes, it is likely your microfiber-only insert is going to leak out of the cover, no matter how great of a cover you have.

What's the solution?  Either don't use microfiber, or add another fabric which holds the wetness under compression.  The best combination seems to be microfiber (or Zorb) with bamboo.  The microfiber absorbs quickly, and the bamboo (placed below the microfiber) slowly absorbs moisture from the microfiber.  For making my own inserts, the microfiber/bamboo combination has given me the best results.

For a great summary of multiple types of fabric and their absorption and performance under compression, visit this page, which summarizes an experiment done by a mom at home.

What have been your experiences with microfiber?  Have you tried Zorb?