Hello, dear wizards of formulating chemistry. Question: if you are testing for stability, besides temperature, do you normally test for light exposure? Also, when a product says "keep in a cool, dry place" does it mean their stability test was different? And, finally, what are the circumstances for PET? It lasts for a month, so do they keep it warm and cozy or just room temp? Thank you!
Comments
UV is not required as many cosmetics are sold in none transparent bottles. Now I tested some producs under UV, plain sun.... not always glorious! EDTA, BHA... are often the solution.
Keep in cool.... refers only to the way the customer should ideally store the product. Stabilities are often conducted at 30 and 40 degrees with... I think 65 and 75% humility.
For the PET, we get this done outside at the moment, but looking at the test, you would think that 30 degrees should be an obvious temperature.