ABSTRACT
Introduction 462
Background 462
Issues with the Current Sunscreen Products 462
Issues with Emulsions 465
Use of Surfactant-Free Dispersions in Sun Care 468
Properties of Lamellar Phase Dispersions 469
La Dispersions of Ultraviolet Absorbers 474
Dispersions of Organic UV Absorbers 474
Physical Sunscreen Suspensions 475
Formulating with Dispersions 475
Defining a Semiquantitiative Aesthetic Scale 475
Preparing the Final Formulation 479
The Advantages of Surfactant-Free Sunscreens 480
Beyond Conventional Sunscreens 485
Conclusion 488
References 488
Appendix 1 489
Sunscreen Formulations 489
INTRODUCTION
The sun may be considered one of life’s ultimate enigmas. On the one hand, it is
critical for the support of life on earth. From photosynthesis in plants to vitamin
D production in mammals, the sun plays an integral role in sustaining our existence.
On the other hand, studies during the past half-century have clearly demonstrated
that too much sun can give rise to physiological complications that can lead to the pre-
mature appearance of aging, the development of uneven pigmentation, the formation
of cancer, and even death in some cases. In fact, incidents of skin cancer are one of the
fastest growing problems in the field of dermatology. Why is this trend occurring
when the knowledge of the damage done by the sun is so well recognized?