Removing Stains from a Boater

[Marshall]

I have an old Boater that I've been working on renovating. I found that an old toothbrush and a little water worked very well for removing dirt, but there are some sweat stains that I'm not sure how to get rid of. The stains are on the brim around the base of the crown (thus I assume they are from sweat).

I tried using a hydrogen peroxide/water mix, as I saw recommended in an old thread, though that had no effect. Do you guys have any thoughts on how I could go about removing the stains?

If it would be helpful I can post pictures later. Thanks!

 

[Marshall]

 

[mayserwegener]

I actually picked up this early 1900s German straw hat cleaner (bleach) a while back. I haven't given it a try though.