At TWENTY, we have always taken a considered approach to formulation. As a UK professional nail brand, our gel products are formulated without TPO, and we’ve worked closely with our chemists to ensure our systems deliver the performance professional nail technicians expect.
As more brands begin transitioning to TPO-free formulas, many nail techs are encountering these systems for the first time. While they are designed to perform just as professionally as traditional gels, there are a few application nuances worth understanding to get the best results.
Here are some key things nail technicians may notice when working with TPO-free gel products.
1. A Slightly More Controlled Cure Profile
TPO (Trimethylbenzoyl Diphenylphosphine Oxide) is known for being a very efficient photoinitiator, meaning it activates quickly when exposed to UV/LED light. When it is removed from a formulation, alternative photoinitiator systems are used instead. Because of this, some TPO-free formulas may have a slightly more controlled cure profile, making correct curing conditions even more important.
For best results, always ensure:
● Your lamp outputs 365 + 405 nm wavelengths
● The lamp is 36W or above
● Full recommended cure times are followed
When cured correctly with the correctly matched professional lamp, TPO-free gels provide reliable and consistent performance.
2. Thin Layers Are Especially Important With Pigmented Colours
Highly pigmented gel colours always benefit from thin, controlled application, but this can be particularly important with TPO-free formulas. Pigment density can affect how efficiently light travels through the gel during curing. Applying thinner layers allows the light to penetrate the product more effectively.
We recommend:
● Applying two thin layers rather than one thicker coat
● Avoiding overloading the brush with product
● Building colour gradually
This is especially relevant for highly saturated shades such as whites, blacks and bold pigments.
3. The Inhibition Layer May Feel Slightly Different
Some nail technicians may notice a slight difference in the inhibition layer (tacky layer) after curing TPO-free products. This layer forms naturally during polymerisation and helps ensure proper bonding between layers of gel.
Depending on the alternative photoinitiator system used, the inhibition layer may feel:
● Slightly more noticeable
● Slightly less noticeable
Both are completely normal and do not indicate incomplete curing when the correct lamp and curing times are used.
4. Surface Preparation Can Support Pigmented Colour Application
When working with highly pigmented gel colours, preparing the surface underneath the colour layer can help ensure smooth, even application.
This can include:
● Wiping the cured base or builder layer with IPA
● Very lightly buffing the surface to remove shine
● Cleansing thoroughly before applying colour
These small steps can help optimise adhesion and colour performance.
The TWENTY Approach
At TWENTY, our TPO-free formulas are designed specifically for professional use, with
performance, safety and reliability at the forefront.
By combining correct lamp specifications, thin application and proper preparation, nail technicians can achieve consistently strong, long-lasting results across the entire TWENTY system.