We are constantly find ourselves explaining to our clients who may be new to our little Selvedge denim world about the differences between these terms.
This one seems to be the biggest misconception: That Raw denim and Unsanforized denim are interchangeable words. It is no ones fault, and it is likely that this has never been laid out clearly enough to comprehend with ease.
There is Sanforized Raw denim. In fact, much of the Raw Selvedge denim world leans toward using Sanforized denim in the production of their denim. Why, you may ask? The answer is simple - shrinkage is maximized to eliminate the calculating and guessing process that often comes with buying Unsanforized denim. So a Sanforized pair of Raw denim means that they have been treated post-production to ensure the fabric will barely shrink any further, but they are still Raw, and will still shrink several more percent with a soak (generally about 3% as a rule of thumb).
Unsanforized denim on the other hand, can also be referred to as loom state or キバタ (Kibata, the Japanese term for Unsanforized). This denim does NOT receive any treatment post-production and is sent directly for cutting and sewing into jeans, as loom state fabric. These jeans are prone to shrink 7-10% (variance can be greater even, and depends on fabric and soak process) with the first soak, and sizing into the right pair for you is an imperative process to find the right fit. Unsanforized is preferred by hardcore enthusiasts due to the character and weave which tends to be much hairer and slubbier in nature. Read about caring for your Unsanforized jeans here.