Understanding Reservoir-Tech and Ethoxydiglycol in Formulations

You are correct in your understanding of the primary functions of Reservoir-Tech and Ethoxydiglycol. They serve different purposes in a cosmetic formulation.

• Reservoir-Tech: This ingredient is designed to form a film on the skin surface, helping to retain active ingredients and release them gradually over time. Its main benefits are reducing irritation from potent actives and providing a sustained effect by controlling the rate of absorption into the skin.

• Ethoxydiglycol: This is a solvent and carrier that enhances the penetration of other ingredients into the skin. It helps solubilize various substances and facilitates their transport across the skin barrier.

Can They Be Used Together?

While not strictly counteracting each other chemically, their mechanisms are different. Reservoir-Tech aims for controlled, slow release, while Ethoxydiglycol promotes faster and potentially deeper penetration. Using both might lead to a complex interaction where the effects could partially offset each other, or the outcome might be less predictable than using one tailored to your specific goal.

Choosing Between Them for Your Formula

For a formula focused on skin barrier repair and rejuvenation using Safe-B3 (Niacinamide), and with a concern for potential irritation or flushing, Reservoir-Tech is generally the more suitable choice. Here's why:

• Irritation Reduction: Reservoir-Tech is specifically noted to help reduce irritation from actives like AHAs and is tested for use with ingredients like Safe-B3. Its slow-release mechanism prevents a sudden high concentration of the active ingredient from entering the skin, which is beneficial for sensitive skin or when using actives at higher percentages.
• Controlled Absorption: It aligns with the goal of controlled delivery, which can be desirable for maintaining a consistent level of the active ingredient on or in the skin over a longer period.
• Safe-B3 and Flushing: Although Safe-B3 is a high-purity Niacinamide designed to minimize flushing, Ethoxydiglycol does increase penetration speed. If flushing is a concern, even with Safe-B3, the controlled release offered by Reservoir-Tech is a more direct way to mitigate this risk compared to using a general penetration enhancer like Ethoxydiglycol.

Ethoxydiglycol is excellent for formulations where maximizing the penetration of specific actives is the primary objective, and controlled release or irritation reduction is not the main concern.

In summary, for your specific formula aiming to nourish and repair the skin with Safe-B3 while minimizing potential irritation or flushing, Reservoir-Tech is likely the better choice due to its controlled-release and irritation-reducing properties. Using Ethoxydiglycol might increase penetration but could potentially work against the controlled delivery mechanism of Reservoir-Tech and might still increase the risk of flushing compared to using Reservoir-Tech alone with Safe-B3.