PARIS — Yon-Ka Paris’ Françoise Mühlethaler has died.

A biochemist by training, she and her sister, Catherine Mühlethaler, an aesthetician, reinvented and ran the skilled skincare brand that was created in 1954 by brothers Ernest and Charles Mühlethaler, plus Ernest’s wife Cécile.

“A prolific, creative mind with infinite imagination, Françoise Mühlethaler explored many horizons, including a love of nature, science and aesthetics,” Yon-Ka said in a press release. “Her motto led her: ‘In the event you imagine in something, do it.’”

She believed in international expansion, helping launch Yon-Ka abroad in 1970. The brand reached markets resembling Belgium, Holland, Scandinavia, Asia and Canada by the mid-’70s and arrived within the U.S. in 1987.

“Despite facing various challenges, Françoise propelled the brand internationally and made Yon-Ka Paris certainly one of the primary French beauty brands to operate within the U.S.,” Yon-Ka said, calling her a pioneer, who “was never held hostage to trends.”

The Mühlethaler sisters co-owned each the beauty brand and the Mühlethaler Laboratories that produce its clean products which are formulated with sustainable ingredients, resembling plants and essential oils.

“Product innovation after product innovation, collection after collection, Françoise Mühlethaler left her mark on our family’s legend and the history of the Yon-Ka Paris brand, while cherishing the values of our family: authenticity, respect an also a taste for adventure,” said Catherine Mühlethaler, general manager of Yon-Ka Paris.

“She steadfastly promoted the talent and expertise of Yon-Ka’s laboratories, and propelled Yon-Ka education excellence, allowing this exceptional know-how to shine worldwide,” Mühlethaler continued. “The best tribute we will pay today is to proceed to follow the trail she traced by — to cite Françoise — ‘turning big dreams into reality and continuing to embrace the current and invent the long run.’”

“Due to her creative genius, generosity and exceptional intuition, Françoise Mühlethaler was ahead of her time, which widely contributed to Yon-Ka Paris’ success worldwide,” said Alexis Wolowinski, general manager of Yon-Ka Paris U.K., who called Mühlethaler “a member of the family, friend, mentor and extraordinary leader, who reinvented the Yon-Ka brand.”