pvl stands for polyvinyl alcohol
polyvinyl alcohol, also known as pvoh, pva, or pval, is a synthetic polymer that is soluble in water. it is effective in film forming, emulsifying, and has an adhesive quality. it has no odor and is not toxic, and is resistant to grease, oils, and solvents. it is ductile but strong, flexible, and functions as a high oxygen and aroma barrier.
the answer is Mol. concentration/time