01
Why hair products contradict each other.
A hair fibre is a coil of keratin (the cortex) wrapped in five to ten overlapping layers of flattened scales (the cuticle), growing out of what is, biologically, skin.
Virgin hair is water-repellent, and there is a specific reason: a lipid layer called 18-MEA is covalently bound to the cuticle's outer surface. It is why healthy hair feels smooth, separates cleanly and does not tangle.
Damage, bleach, heat, UV, friction, does two things. It oxidises the disulfide bonds that give the cortex its strength, converting them into cysteic acid, and it strips 18-MEA. The fibre flips from water-repellent to water-attracting and its surface becomes increasingly negatively charged. Scales lift. Friction climbs. Hair tangles, snaps and goes dull, dullness is simply lifted scales scattering light instead of reflecting it.
Here is the contradiction most ranges never resolve. Scalp wants one thing, lengths want another. Scalp is skin: it has sebum, a microbiome and a pH around 4.5–5.5, and it needs genuine cleansing. Damaged mid-lengths and ends need deposition and protection. A shampoo aggressive enough to clean a scalp properly will strip ends; a formula rich enough to repair ends will leave a scalp greasy and flat.
The usual answer is to sell you three products and hope you apply them in the right places. Tricelleon's premise is that the fibre's own chemistry can be used to route the right treatment to the right zone automatically.
3zones addressed in one step, scalp, cuticle, cortex
5–10overlapping scale layers in a healthy cuticle
~3.67hair's isoelectric point, why acidic pH keeps cuticles flat
18-MEAthe bound lipid layer damage strips first