Liz Crenshaw, consumer reporter for NBC4 in the Washington DC metropolitan area, showed us how we lose product each and every time we toss a container that no longer pumps, squeezes, or otherwise dispenses product. I have been known to cut open plastic containers to get the last drop of product out. She demonstrated that on TV last night.
She cut into plastic containers of Cetaphil and Aveeno. Working with a scientist at Marymount University, she demonstrated how more than 10% of the product can be left in the container, basically inaccessible unless you are willing to cut. Her findings match those of Consumer Reports.
It all has to do with the ease of flow, which is where rheology comes in. It's the science of flow. It should be no surprise that liquids flow more easily than creams and gels, so the thicker your product is, the more likely it is that some will be left behind - unless you take "drastic measures."
If I like a product and want to get every last drop, I cut into the container if possible. The last time I did this was with a Sisley Supremya sample. At $750 for the full-sized product, Supremya is costly. I wasn't going to leave a drop unused!
Is this a manufacturer's conspiracy? Liz thinks not. Simply science!
Photo courtesy of The Society of Rheology