ABSTRACT
Introduction 218
The Electromagnetic Spectrum 218
Effect of UV Radiation on the Skin 220
Classification of UV Filters 221
PABA and p-Aminobenzoates 224
Salicylates 226
Cinnamates 227
Benzophenones 228
Anthranilates 229
Dibenzoylmethanes 230
Camphor Derivatives 230
Miscellaneous Compounds 231
Mechanism of Sunscreening Action 231
Effect of Vehicle on the Efficacy of UV Filters 232
pH Effects on UV Filters 233
Effect of Emollients on the Efficacy of UV Filters 233
Effects on the Extinction Coefficient 235
The Future of UV Filters 235
Conclusions 237
References 238
INTRODUCTION
The recent evidence linking ultraviolet-A (UV-A) rays to serious damage beyond
the fashionable and sought-after tan is daunting (1). These and other important
findings have prompted the cosmetic industry to create new sunscreen products
that would afford the consumers more efficient protection. Since the cosmetic
industry began formulating a myriad of new sunscreen active agents into an
array of functional products, it has become necessary for the cosmetic chemist
to know more about the chemical structure and reactivity of UV filters and
their potential interaction with other ingredients in the sun care cosmetic
formulations.
