Flourination should be requested from the bottle supplier. It is not something to do at home. It can be done in varing degrees. If you have a product that is migrating through the walls of an HDPE bottle level 5 flourination should be considered, to greatly reduce or eliminate paneling. The cost of flourination contributes about 10 to 15 cents per bottle, typically.
Auto-Rx went away from HDPE to PETE material of their new bottle. I think this was a good move.
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