D.E.F.I. stands for Device for Exclusive Formula Integrity, which describes the system that allows the product to be kept intact, with absolutely no preservatives, in a large format tube. The D.E.F.I. system guarantees the product’s sterility before and during use.

An airless dispenser prevents air from entering and thus prevents oxidation of the product. However, there is a “dead volume” which remains at the top of the dispenser that contains some of the product. There is therefore the risk of retro-contamination and the need for preservatives. The Tolérance Extrême D.E.F.I. system also prevents any air from entering as well as the oxidation of the product. However there is no dead volume, and retro-contamination is not possible. The formula is sterile and remains sterile throughout product use.

Partial sterilization consists of producing a “formula” under conditions that are controlled but not sterile. The sterilization takes place with the formula produced, before it is packaged in a sterile environment (this is the principle behind UHT milk). Tolérance Extrême’s complete sterilization process consists of producing and packaging in a sterile environment. This means:

- pre-sterilization of all equipment coming into contact with the product,
- sterilizing filtration of all the liquid or soluble material used in the composition of products
- packaging in a sterile environment.

Tolérance Extrême products were made for the most demanding skin, which does not tolerate any substance that is irritant or susceptible of facilitating penetration by allergens.
These products are made for all consumers in search of safe formulas:

- Hypersensitive and allergic skin.
- Skin intolerant of traditional cosmetics.
- Skin allergies.
- Acute manifestations of irritation (redness, tightness, tingling etc.)
- Following medical procedures (laser treatment, chemical peels etc.).

Hypersensitive skin has altered barrier function and is potentially more reactive to bacterial contamination of formulas or to the effect of certain substances (such as preservatives).
Tolérance Extrême formulas are perfectly sterile and free from preservatives, offering the advantage of being free of all potential irritants.

A preservative is a substance destined to prevent the development of micro-organisms in a formula. Annex VI of the relevant European Directive lists 57 of them.
However, some of the substances contained in cosmetic formulas for other purposes (adding fragrance, toning, firming etc.) may also have anti-microbial properties that inhibit the growth of micro-organisms.
These unlisted substances are “substances with an incidental preservative function” (example: certain alcohols, essential oils, ethylhexylglycerin etc.).

Tolérance Extrême products do not contain listed or unlisted preservatives (substances with an incidental preservative function). The difference is linked to the fact that the formula is sterile and that its integrity is guaranteed by the D.E.F.I. system.

With only 6 ingredients in the No-rinse Cleansing Lotion and 9 in the Soothing Moisturizing Cream, Tolérance Extrême offers ultra-safe formulas that focus on the essential. The ingredients are pure. They include:

• Avène Thermal Spring Water, naturally soothing and anti-irritant.
• Glycerin codex, a moisturizing emollient.
• Paraffin codex, Cyclomethicone and Safflower Oil, three emollient substances.
• Squalane, which restores the skin barrier.
• Textural agents, which provide the necessary viscosity for the mixing of the phases in pseudo-emulsions.