Noticed a word さらさら appearing on various products' packaging I've got from Japan. The main translation ("rustling sound") doesn't seem like something you'd ordinarily expect to see there... Especially on such a variety of products as tea, nappies and books (admittedly, might have been an ad on a plastic packaging for something else in the latter case). It is shown on front title side alongside the product description and brand name.
Here are a couple of examples I found around the house:
So, what does this mean?