chapter  18
32 Pages

Formulating Sunscreen Products

Introduction 354

Formula Types 356

Emulsions 356

Oils 358

Gels 359

Sticks 361

Mousses 361

Aerosols 362

Ointments 362

Formulating Basics 362

Principles of Emulsification 362

Selecting Key Ingredients 365

Emulsifiers 365

Emollients 367

Film Formers 368

Stabilizers/Protectants 369 Organic Sunscreens 370

Inorganic/Particulate Sunscreens 372 Fragrances 373

Achieving Formula Goals 373

To Achieve High SPFs 373

To Achieve Water Resistance 374

To Obtain Mild Formulations 374

Patent Issues 375

Stability Evaluation 375

Organoleptic Considerations 376

The Use of Antioxidants in Sunscreen Formulations 376

Formulations 376

References 382

INTRODUCTION

With the publication of the Final Sunscreen Monograph on May 21, 1999, the

“playing field” for marketers of finish goods became more complex and now

offered some new opportunities for “marketing handles.” Although some

claims could no longer be made, such as those relating to aging and wrinkling,

we now see the appearance of strong claims dealing with ultraviolet-A (UV-A)

radiation. In fact, the US Food and Drug Administration (FDA) has even pub-

lished a list of those sunscreens for which usage permits UV-A reference.

Some additional claims have begun to appear deal with protection against infra-

red (IR) radiation. The FDA Tentative Final Monograph (TFM) does not deal with

IR in any way. Thus, IR claims are cosmetic and not drug claims. They must

be substantiated for the Federal Trade Commission (FTC), but not the FDA.

Marketersalso have made claims for “all-day” waterproof protection. The FDA

no longer allows a waterproof claim. They feel that the term suggests an

absolute-waterproof-which is not borne out by the currently available test

methods. The sweat proof claim can now be made, if the product meets the

requirements for a very water-resistant claim. Additionally, extended claims

such as “all day” are not permitted.