Silicones

Core Identity: A class of synthetic polymers with a silicon-oxygen (Si-O) backbone and organic side groups (e.g., methyl). They are not natural ingredients.

Most Common Type: Dimethicone. This is the "silicone" found in the vast majority of skincare and cosmetic products.

Key Properties & Efficacy:

1. Exceptional Skin Feel Modifier:

   • Instant Blurring: Fills in skin fine lines and pore depressions, delivering an immediate silky-smooth, even, matte finish. It is a core ingredient in many primers and foundations.

   • Lightweight & Non-Greasy: Provides a smooth, non-sticky, and highly desirable texture.

2. Highly Effective Film-Former & Occlusive Agent:

   • Moisture Lock: Forms a breathable, protective film on the skin's surface, effectively preventing water loss and enhancing hydration.

   • Barrier Protection: Shields the skin from external irritants (e.g., makeup, pollutants). Commonly used in diaper rash creams to isolate urine irritation.

3. Stability & Safety:

   • Inert: Chemically stable, unlikely to react with other ingredients or deteriorate.

   • Low Sensitization Potential: Generally non-comedogenic (does not clog pores) and hypoallergenic, making it suitable for sensitive skin.

Common Applications:

• Medical Use: Silicone gels/sheets (a first-line choice for scar treatment).

In a Nutshell:
Silicones are the "magicians" of product texture and performance, providing instant smoothing, effective moisturization, and reliable protection. They are safe and have extremely widespread applications.