Description

Synovea® HR is a high-purity form of 4-Hexylresorcinol (HR) — a naturally occurring alkylresorcinol derived from cereal grains like rye. With over 80 years of safe use in the food and pharmaceutical industries, HR holds GRAS status and is widely recognized for its effectiveness as an anti-browning agent in shrimp and fresh-cut produce.

Now redefined for advanced skincare,  Synovea® HR was created as a powerful skin lightening and tone-evening ingredient. Its effectiveness is linked to its exceptional purity (≥99.5–99.9%), eliminating trace levels of resorcinol — a known skin irritant — and hexanoylresorcinol intermediates.

Proven Efficacy, Backed by Clinical Science

  • A randomized, double-blind study conducted by UC-Davis dermatologists showed 1% Synovea® HR performs equivalently to 2% hydroquinone in reducing visible pigmentation on the face and hands — with excellent tolerance (Wu et al., Archives of Dermatological Research, 2022).

  • A Unilever-sponsored study found synergistic effects between HR and niacinamide, enhancing anti-melanogenic activity in vitro, and confirming in vivo safety and efficacy in human trials (R. Shariff et al., Int. J. Cosmetic Science, 2021).

Key Benefits:

  • Brightens and evens skin tone with high efficacy

  • High purity minimizes irritation and maximizes performance

  • Demonstrated synergy with niacinamide

  • Clinically proven results on both face and hands

  • Well tolerated and safe for topical use, even on sensitive skin

Suggested Synergists / Additives for Improving Skin Lightening / Even Toning Effects

Synergist/Additive Why? Use level
Niacinamide
  • Inhibits transfer of melanin from melanocytes to keratinocytes
  • Clinically observed synergism with HR
1-2%
Synoxyl AZ
  • Non-sacrificing broad-action antioxidant
  • Reduces Cu-on induced melanin synthesis
  • Being senolytic, it reduces freckles
  • Reduces pigmentation & redness in photodamaged skin (clinical)
1%
Synastol TC
  • Strong peroxidase inhibitor, Glycation inhibitor & reversal
  • Broad-spectrum antioxidant & anti-inflammatory
  • Reduces pigmentation (clinical)
0.50%
Sytenol A
  • Works by modulating  α-MSH pathway & stimulating E-Cadherin
0.50%
Sytheon limited was purchased in November 2024 and their line of products including this one is now available within the Hallstar Beauty portfolio.
      • INCI
        Enter INCI name
        Hexylresorcinol