Penetration of cationic conditioning compounds into hair fibers: a TOF-SIMS approach

Cationic conditioning compounds protect against hair damage caused by cosmetic chemical treatments and grooming practices. They also enhance the retention of moisture. However, the question as to whether they do this superficially by residing on the hair surface or by penetrating into the fiber remains unanswered. In this work, an attempt has been made to show the penetration of a low-molecular-weight cationic conditioning compound into the hair cortex using the time-of-flight secondary ion mass spectrometry (TOF SIMS) method, applied in earlier research to show the penetration of oils into hair. An example of the practical benefit of such penetration into the cortex in greatly improving the fatigue resistance of hair has been discussed.