Turning supplier trade names into INCI names

The label on the drum says something like "Crodamol IPM" or "Optiphen Plus" or "Emulsifying Wax NF," and none of those words are allowed to appear on your cosmetic notification. Regulators speak INCI, the International Nomenclature of Cosmetic Ingredients, which is the shared naming system that turns a supplier's marketing name into one standard term everyone agrees on. Water is Aqua. Shea butter is Butyrospermum Parkii Butter. Every ingredient has an INCI name, and the trick is finding the right one without introducing an error.

Most of the pain here comes from one fact: a single trade name can be one INCI, or it can be five.

Single ingredient, easy case

When a raw material is one substance, the mapping is clean. "Crodamol IPM" is Isopropyl Myristate, CAS number 110-27-0. You look it up once, write down the INCI name and CAS, and you are done. Suppliers usually print the INCI right on the technical data sheet or the safety data sheet, often in a section labeled composition or ingredients.

The habit worth building is to never copy the trade name into your ingredient list, even as a placeholder. Placeholders have a way of surviving all the way to submission.

Blends are where it goes sideways

Plenty of raw materials are pre-made blends. An emulsifying wax might be Cetearyl Alcohol plus Polysorbate 60. A preservative like Optiphen is Phenoxyethanol plus Caprylyl Glycol. A "vitamin E" oil might be Tocopherol carried in a base of Helianthus Annuus Seed Oil.

When you buy a blend, your notification does not list the blend, it lists the components. So one line on your purchase order becomes two, three, or four lines on your ingredient list, each with its own INCI name and its own percentage of the final formula. This is the single most common place a filing goes wrong, because people list the blend at its use level and never break it apart.

Here is the math that matters. If your formula is 3 percent of a preservative blend that is 90 percent Phenoxyethanol and 10 percent Caprylyl Glycol, your formula actually contains 2.7 percent Phenoxyethanol and 0.3 percent Caprylyl Glycol. That Phenoxyethanol number is the one a regulator checks against its restricted list, and it has a limit. Listing the blend at 3 percent hides the number that decides compliance.

Getting the CAS number right

INCI names identify an ingredient by nomenclature, CAS numbers identify it by chemistry. The CAS Registry Number is a unique code for a specific substance, and it removes ambiguity when an INCI name could point to more than one thing. Some ingredients have several CAS numbers, some botanical extracts have none, and that is normal.

Pull the CAS from the supplier's safety data sheet section 3 where you can, and treat a missing CAS on a well defined chemical as a reason to double check rather than a dead end.

A workflow that holds up

1. For each raw material, open the supplier's technical data sheet and safety data sheet side by side.
2. Find the composition section and write down every component, its INCI name, and its CAS number.
3. Note the concentration of each component within the raw material.
4. Multiply by your formula's use level to get each component's real percentage in the finished product.
5. Combine duplicates. If two raw materials both contribute Glycerin, add the amounts so Glycerin appears once at its true total.

Do that and your ingredient list reflects what is actually in the bottle, which is the whole point of the exercise.

Why the wrong answer is expensive

The reason to be careful is that an ingredient list feeds straight into the compliance check. If a percentage is off because a blend was not broken apart, an ingredient that is actually over its restricted limit can look fine, and one that is fine can look over. Off the shelf AI tools are especially shaky here. They will confidently return an INCI name and a CAS number that look right and are subtly wrong, and the allergen and restricted list checks are exactly where subtle errors cause real problems.

We built the INCI matching in Cosmetic Comply to do the boring version correctly. You upload the supplier documents, the blends get expanded into their components, the percentages get carried through the math, and every result comes with a confidence score so a human knows where to look. Then a reviewer checks it before it ever reaches the regulator.

If you only fix one thing about your ingredient list this week, make it the blends. That is where the numbers that decide compliance are hiding.