It would have been cheaper to throw the bottles away but that was not acceptable to the manufacturer. Theories Refined Because of the observation that the charge was mobile enough to flow out of the bottles into the salt water and dissipate to ground, at least a portion of the theory about charge migration made sense. However, the difference in this capacitor structure is the charge on the outer surface of the dielectric medium separating the plates. Since the bottle had a relatively fixed and large mono-polar charge, it could cause induction to the shampoo inside the bottle. In reality, both of the theories initially considered are involved in this unusual case study.
Principles of induction come into play as well as charge migration.
Because of the unique structure of the filled shampoo bottle, it was considered a type of self powered capacitor. The charging mechanism initially resided in the charge on the outside of the polymer bottle under the metallic graphics. Charge induction to the shampoo allowed charge separation within the shampoo. The manufacturer changed the design of the bottle graphics to avoid the corona treatment. All of the existing stock of printed bottles were used after the soak in the salt water so it reduced the need for land fill of the bottles in stock as they could not be reprocessed due to the metallic ink.