Introduction: Why Multilayer Moisture is Important

The stratum corneum comprises the top 15-20 μm of the skin and contains the layers directly exposed to the external environment. The SC is in a constant state of cellular renewal, and the SC cells (corneocytes) progress through different stages of development and ultimately desquamation.²

The SC can be viewed as being divided into 3 regions: the top layers, core layers, and deep down layers.

• The corneocytes within the top layers (0 to 4 μm depth) are most vulnerable to and affected by environmental damage;
• The core layers (4 to 12 μm depth) are the middle layers of the SC, containing more mature corneocytes;
• The deep down layers (12 to 20 μm below the skin surface) are most proximal to the living epidermis and contain cells early in the SC migratory process.

Presently, moisturizers typically address SC hydration with humectants, occlusives, and emollients.¹It is important that all layers of the SC are adequately hydrated; yet, traditional moisturizers may not adequately address these needs, particularly the needs of the uppermost surface layers. Glycerol is the most commonly used humectant that absorbs and delivers water to the corneocytes within the SC.² While glycerol is very effective in moisturizing the core layers of the SC, research suggests that the top layers may require even further hydration.³ Occlusive agents such as petroleum jelly can help maintain water within the top layers; however, their use can be associated with an unpleasant residue on the skin.^4,5

Thus, a need remains for a highly effective moisturizer that can target all of the critical layers of the SC and effectively hydrate it throughout.

1.    Epstein HA. Skinmed. 2004;3(5):279-280.
2.    Harding CR, Watkinson A, Rawlings A. Int J Cosmet Sci. 2000;22:21-52.
3.    Unilever, data on file.
4.    Lynde CW. Skin Therapy Lett. 2001;6(13):3-5.
5.    Del Rosso JQ. Cosmetic Dermatology. 2003;16(11):19-31.

The Science behind Stratys-3™

Unilever researchers have identified moisturizing agents that effectively complement the efficacy of glycerol. Our work has highlighted 2 such molecules: glycerol quat (GQ) and hydroxyethyl urea (HEU). GQ is a quaternized glycerol derivative and an even more robust humectant than glycerol, having 4 times more moisture-binding capacity than glycerol alone.¹ Furthermore, GQ is less lipophilic and therefore more likely to be retained within the surface layers of the SC compared with glycerol.¹ In contrast, HEU can penetrate more deeply into the SC to deliver hydration to the deep down layers.¹ The combination of glycerol, GQ, and HEU was designed to deliver moisture across all the layers of the SC to provide superior hydration* to the skin.¹

•    Glycerol Quat (GQ): Helps to deliver unprecedented moisture to the top layers of the SC
•    Glycerol: Primarily hydrates the core layers of the SC
•    HEU: Designed to penetrate to and hydrate the deep down layers of the SC

*Versus leading everyday body lotions.

1.    Unilever, data on file.

Clinical Results

This section includes 3 figures that describe several clinical studies of Stratys-3^TM:

•   Figure 1: Superior improvement in dryness with Stratys-3™ combination compared with glycerol
•   Figure 2: Superior delivery of short-term moisture to stratum corneum from lotion base with Stratys-3™ compared with glycerol
•   Figure 3: Superior moisture of Vaseline® Sheer Infusion™ with Stratys-3™ compared with leading everyday body lotions


Figure 1: Superior improvement in dryness with Stratys-3™ combination compared with glycerol¹

• Visual dryness was evaluated using the Kligman 0-4 point grading scale.
• 20% (w/w) solutions of Stratys-3™ and glycerol were applied twice daily.
• Both applications resulted in significant reduction in dryness after 2 days.
• The Stratys-3™ solution led to a significantly greater reduction in dryness compared with glycerol alone.

1.    Unilever, data on file.

• Study conducted in Connecticut in March on 18 subjects.
• Legs were preconditioned for uniform dryness.
• Humectant solutions were applied (2 mg/cm²) by clinician twice daily to marked test sites.
• Visual evaluations were conducted by a trained assessor.

Figure 2: Superior delivery of short-term moisture to stratum corneum from lotion base with Stratys-3™ compared with glycerol¹

• Skin hydration was measured using Skicon and Corneometer methods.
• A direct comparison of a fully formulated lotion containing 20% (w/w) Stratys-3™ and the equivalent lotion containing 20% (w/w) glycerol only.
• Skin hydration was measured 4 hours after single product application.
• Stratys-3™ delivered significantly more overall moisture to the SC than the identical lotion with glycerol only.

1.    Unilever, data on file.

• Study conducted in Connecticut in January on 14 subjects.
• Legs were preconditioned for uniform dryness.
• Lotions were applied (2 mg/cm²) by a clinician to marked test sites.
• Skin hydration measurements were conducted by trained assessor.
• Experiments were conducted using a Skicon 200EX Skin Hygrometer (I.B.S. Ltd, Japan) and Corneometer CM825 Skin Moisture Meter (Courage & Khazaka, Köln, Germany).

Figure 3: Superior moisture of Vaseline® Sheer Infusion™ with Stratys-3™ compared with leading everyday body lotions

• Skin hydration was measured using Skicon methods.
• A direct comparison of Sheer Infusion™ with Stratys-3™ versus the leading hand & body lotions in North America and Europe (Nielsen 52-week, 2.5 outlet data).
• Increase in skin moisture measured ½, 2, and 4 hours after single product application.
• Results demonstrate that lotion with Stratys-3™ delivers significantly more moisture to the SC than any of the leading body lotions.

• Study conducted in Connecticut in December on 168 subjects (14 subjects per each of 12 products).
• Legs were preconditioned for uniform dryness.
• Lotions applied (2 mg/cm²) by clinician to marked test sites.
• Skin hydration measurements were conducted by a trained assessor.
• Experiments were conducted using a Skicon 200EX Skin Hygrometer (I.B.S. Ltd, Japan).

Vaseline^® Sheer Infusion™ is the first Vaseline^® product with our breakthrough Stratys-3™ technology.

Figure 1: Stratys-3™  Molecule

The combination of glycerol, GQ, and HEU represents a scientific breakthrough in hydration of all layers of the stratum corneum. The clinical benefits of Stratys-3™ have been proven in patients with normal and extremely dry skin; additional studies are ongoing. Stratys-3™ is now available in Vaseline® Sheer Infusion™ as a highly effective everyday body lotion.