Fiber Filler Mask 1L - Cadiveu Blonde Reconstructor is the Step 2 protein mask of the Blonde Reconstructor salon system, a slightly acidic pH 4.5 to 5.5 conditioning mask that rebuilds bleached and blonde hair with low-molecular-weight keratin amino acids and hydrolyzed pearl. Those small proteins restructure the fibre from the cortex out through the cuticle, which is how strength and condition come back after lightening. It is a professional back-bar step, layered under the pH-Balancing Mask, not a home mask.

Why the Fiber Filler Mask

Bleaching leaves the fibre porous and protein-depleted, which is what makes lightened hair feel dry, weak and rough. Fiber Filler answers that with proteins small enough to penetrate: keratin amino acids and hydrolyzed pearl restructure the fibre starting at the cortex and working out through the cuticle, while the slightly acidic pH of 4.5 to 5.5 keeps the cuticle from swelling as they deposit. Run as Step 2 after the Clarifying Shampoo and before the pH-Balancing Mask, it rebuilds strength and condition so the finished blonde looks and feels healthy rather than over-processed.

Key Ingredients

The reconstruction comes from a keratin amino acid complex and hydrolyzed pearl, low-molecular-weight proteins that reach into the cortex to rebuild the fibre, supported by panthenol and shea (butyrospermum) lipids for condition and slip. The mask is set to a slightly acidic pH of 4.5 to 5.5 so the cuticle stays compact as the proteins deposit. Because it contains keratin amino acids and hydrolyzed pearl, the mask is not vegan.

What to Expect

In the five minutes it processes, the mask floods the fibre with protein and lipids and leaves the hair softer, stronger and easier to comb, still damp and ready for the pH-Balancing Mask on top. It is a reconstruction step in a professional chronogram rather than a standalone treatment: paired with Step 1 and Step 3 it rebuilds bleached hair without weighing it down, and the result reads as healthy, resilient blonde.

Who It Is For

• Colorists and salons running the Blonde Reconstructor reconstruction protocol
• Bleached, lightened or chemically weakened blonde hair that needs protein rebuilt
• A post-bleach service that wants strength and condition back before finishing

Who It Is Not For

• Home users after a quick conditioning mask: this is a professional Step 2 in a salon chronogram
• Anyone wanting a vegan formula, which this is not, as it contains keratin amino acids and hydrolyzed pearl
• A colorist who reaches for protein over uncleared mineral build-up

Professional tip: leave the mask on the full five minutes and use gentle heat to drive the proteins in, then layer the pH-Balancing Mask straight over it without rinsing. On very porous, over-processed lengths, a second coat through the mid-lengths and ends rebuilds them more evenly.

How to Use

In the salon, Fiber Filler Mask works as one step of the full Blonde Reconstructor chronogram, so it is used alongside the other steps rather than on its own. Run the sequence in order, with its step in focus:

1. Step 1, Clarifying Shampoo: apply to damp hair, work into a lather, leave on for 5 minutes and rinse thoroughly (repeat if needed) to clear residue and heavy metals.
2. Step 2, Fiber Filler Mask: on clean, towel-dried hair, work in sections from the nape hairline, comb through for even distribution, then leave on for 5 minutes and do not rinse.
3. Step 3, pH-Balancing Mask: layer it straight over the un-rinsed Step 2, section and comb through, leave on for 10 minutes, then rinse clean.
4. Finish, the Blonde Lock leave-in: distribute a small amount evenly through wet or dry hair and do not rinse.

For a bleach service, add 6 g of Unbroken Blonde per 20 g of bleaching powder and mix to a homogeneous cream before you lighten, then run the reconstruction chronogram above.

Use gentle heat over the mask steps to optimize the result.

After the service, send the client home with the Blonde Reconstructor home care (Blonde Keeper Shampoo and Acidic Mask) to hold the result between visits.

Where It Fits in the Blonde Reconstructor System

Fiber Filler is Step 2 of the salon system: clarify with the Clarifying Shampoo (Step 1), rebuild with Fiber Filler, then seal and rebalance with the pH-Balancing Mask (Step 3); for a bleach service, Unbroken Blonde is added to the lightener for extra fibre protection. The four sit in the Blonde Reconstructor salon range, and clients keep the result up with the Blonde Reconstructor home care.

In Short

• The Step 2 protein reconstruction mask of the Blonde Reconstructor salon system: 1L, professional use
• A slightly acidic pH 4.5 to 5.5 mask with low-molecular-weight keratin amino acids and hydrolyzed pearl
• Rebuilds bleached and blonde hair from the cortex out; leave on 5 minutes, do not rinse, layer Step 3
• Not vegan (contains keratin amino acids and hydrolyzed pearl); a silicone-conditioned mask