Hexylresorcinol has a 95-year history of use in food and pharmaceuticals, but its benefits as an active ingredient for skin care applications have only begun to be realized.
In 2007, Sytheon introduced hexylresorcinol to the cosmetic market as a skin lightener and even toner under the trade name Synovea® HR. As a globally approved, highly pure active with excellent skin tolerance, Synovea® HR has become an increasingly sought after ingredient. In this blog post, we discuss:
- The definition and origins of hexylresorcinol
- Hexylresorcinol in the skin care industry (Synovea® HR)
- 4 important characteristics of Synovea® HR
- Formulation examples and tips
What Is Hexylresorcinol?
Hexylresorcinol is inspired by the natural alkyresorcinols family, which are amphiphilic phenolic lipids found in the bran fractions of rye and other cereals. Produced by organic synthesis, hexylresorcinol has GRAS (Generally Recognized as Safe) status and is commonly used in the food and pharmaceutical industry.
For example, it’s known to prevent melanosis in shrimp and extend the storage life of fresh-cut fruits such as apples and mangoes. Hexylresorcinol is also used in throat lozenges to provide temporary relief to mouth and throat symptoms due to its antiseptic and anesthetic properties.
How can hexylresorcinol be used in skin care applications?
Hexylresorcinol in Skin Care: Synovea® HR
Synovea® HR is known as the gold standard in skin brightening and even toning. Its exceptional efficacy can be attributed, in part, to Sytheon’s ability to attain highly purified hexylresorcinol (>99.5-99.9%), which is essentially free of resorcinol (a known skin irritant) and its intermediate, hexanoylresorcinol.
It works by modulating at least eight sites in the melanogenesis pathway, which means it can influence melanin production at many different points. It can simulate or increase glutathione, reducing oxidative stress and resulting in mitigating the harmful effects of free radicals on the skin. It also inhibits NFκB, which addresses conditions associated with inflammation.
- Skin Lightening: Synovea® HR brightens complexions and provides effective melanin inhibitory activity. It is proven to have the most effective melanin inhibitory activity over other well-known commercial products.
- Even Toning: Synovea® HR provides significant improvement in skin clarity and complexion.
- Hyperpigmentation & Dark Spot Correction: Synovea® HR aids in pigment reduction without affecting the surrounding areas.
- Dyspigmentation: 1% Synovea® HR has been found to match the effectiveness of 2% hydroquinone in minimizing dyspigmentation on the face and hands, without the safety concerns of hydroquinone.
Synovea® HR is the gold standard for these uses in skin care thanks to the following four characteristics.
4 Important Characteristics of Synovea® HR
#1. Excellent Safety Profile
Synovea® HR provides the best ratio between safety and performance, and it has the clinical studies to support it.
As mentioned, it has a purity level of >99%, resulting in Synovea® HR being able to interact well with all skin types. In fact, it offers the following skin protection properties:
- Skin Protection: Up-regulates glutathione, glutathione peroxidase and glutathione reductase.
- DNA Protection: Provides long-term protection of DNA degradation under UV light.
- DNA Repair: Inhibits DNA damage and improves DNA repair via NFκB pathway.
- Protein Protection: Protects collagen and other proteins by reducing Glycation.
#2. Photochemically Stable
Synovea® HR can’t be easily degraded by exposure to UV light or other forms of radiation, so it remains effective for a longer period of time. This is beneficial for both the product formula and the consumers using it. Photochemical stability extends the shelf life of the product, and consumers can use the product over a longer period of time with consistent and safe results.
#3. Clinically Validated
Like all Sytheon active ingredients, Synovea® HR has been rigorously tested to prove clinically efficacy and safety.
Some key results from clinical studies include:
- 2-4 times more effective than hydroquinone
- Significant improvements in skin lightening and even toning
- Significant improvements in skin complexion
- Significant reduction in skin age spots (20% in 4 weeks)
Synovea® HR is a true multifunctional active that can address multiple skin concerns due to its diverse range of actions on the skin, including reducing melanin production, neutralizing free radicals, stimulating collagen production, and more.
Hexylresorcinol has clear applications in skin care, and Synovea® HR stands out as a high performing, safe, and versatile active. Here’s how to use it in your next formula.
How to Formulate with Synovea® HR
There are many different types of formulas that Synovea® HR can be used in as the main active ingredient, including creams, serums, and lotions.
It can also be combined with other ingredients to enhance the benefits. Here are two examples:
#1. Even Toner Cream with Synovea® HR and Synovea® EL
Ethyl linoleate is a very good solubilizer for hexylresorcinol. It’s clinically proven to lighten UV-induced skin pigmentation by accelerating post-translational proteolytic degradation of tyrosinase.
By adding Synovea® HR and Synovea® EL (Ethyl Linoleate) to the skin-friendly emollient Caprylic/Capric Triglycerides, Sytheon has created an elegant, easy-to-use and very cost-effective synergistic skin lightening blend: Asyntra® SL. Asyntra® SL’s recommended use level is 2 to 4% and is commonly used in even toner creams.
#2. Dark Spot Corrector with Synovea® HR and Niacinamide
Niacinamide is a multifunctional ingredient that works well with all skin types and concerns. Specifically, it’s known to minimize enlarged pores, add moisture, and brighten skin. It can be formulated alongside Synovea® HR to enhance its skin brightening and even toning benefits. For example, Synovea® HR and niacinamide make a powerhouse dark spot corrector.
Here are some other tips about formulating with Synovea® HR:
- Suggested use level: 0.5 to 1.0%
- Recommended pH: <6
- Pre-solubilize in appropriate solvent before adding to the final formulation
- Oil-soluble ingredients: hydrophobic emollient esters and other high polarity esters, Hydra Synol® DOI, Caprylic/Capric Triglycerides, and Synovea® EL
- Water-soluble ingredients: Ethoxydiglycol, Butylene Glycol, non-ionic solubilizers, glycerol, and a wide range of glycols
- Not recommended with Ethanol
Hexylresorcinol is a well-researched, established ingredient with applications across many industries. For beauty brands seeking to use hexylresorcinol for skin brightening and even toning properties in their next skin care formula, Synovea® HR is the best choice. It’s globally approved, REACH registered, and patented, and multiple clinical studies with Synovea® HR demonstrated its strong performance in skin brightening and hyperpigmentation control for all skin types.