Write the residual DEA limit on the request. Do not assume a foam sample is a compliant cosmetic grade.
Two lines on the purchase order
Amide assay tells you how much active foam booster you bought. Residual DEA tells you how much unreacted alkanolamine remains. A cheap high-residual grade can look active and fail a cosmetic file.
Esteem’s amidification pages describe the route from fatty acid and alkanolamine. The commercial request still has to carry the limits your customer already signed.
Do not hide it in “cosmetic grade”
Those words vary by supplier. Write numbers: assay, residual alkanolamine, color, and the end use. If you need a nitrosamine statement, ask for it as a statement, not as a foam test.
Household dish liquids and industrial degreasers may not carry the same limit. Ordering the tightest grade for every tank raises cost without a specification.
Certificate contents
Free amine and acid value still describe the reaction. Include them if your quality system already tracks monoethanolamides that way.
Relabeling CDEA as “amide surfactant” in a DEA-free formula is a documentation failure even when the foam is good.
| Item | Why it is there | Not a substitute |
|---|---|---|
| Amide assay | Dose and foam | Residual DEA |
| Residual DEA | Cosmetic limit | A foam cylinder |
| Color | Clear liquids | Assay |
| End use | Which limit applies | One global grade |
What the reaction leaves behind
Cocamide DEA is made by amidification of coconut fatty acid, or a derivative, with diethanolamine. The amide is the foam booster. Diethanolamine that never reacted remains as residual DEA. Water is the other product of the condensation. Stopping the reaction early, or running with a large excess of amine, raises that residual. The foam can still look excellent because the amide is present.
Cosmetic buyers cap residual DEA for that reason, and because the secondary amine is the species discussed in nitrosamine control. A foam cylinder does not measure it. A certificate line does. Industrial and household buyers may set a different cap, or none. The end use decides which certificate you are buying.
Assay, residual, and color do different jobs
Amide assay tells the plant how much active to dose. Residual DEA tells quality whether the lot meets the cosmetic file. Color tells you whether the clear liquid will show the grade. None of the three stands in for the others. A dark, high-assay, high-residual lot can pass a sink test and fail both the color standard and the compliance file.
“Cosmetic grade” is not a number. Write assay, residual alkanolamine, color, and end use. If you need a nitrosamine statement, ask for that statement. Do not treat a tall foam as evidence that the statement would pass. CMEA is specified with residual monoethanolamine and free amine. It is not “CDEA with the DEA line left blank.”
Where a tight spec is wasted
Leave-on products and many rinse-off cosmetic brands need the tight residual limit. A workshop cleaner or a hand-dish liquid may not. Ordering the tightest grade into every tank raises cost and does not improve soil removal. Ordering an unspecced industrial amide into a DEA-free shampoo is a documentation failure even when the foam is good.
Do not substitute CMEA into a formula built on CDEA without a new foam and viscosity curve. The hydrophobe family is similar and the head group is not. Relabeling CDEA as “amide surfactant” on a DEA-free batch sheet does not change the molecule in the tote.
How to Specify with Esteem
- State cosmetic, household, or industrial.
- Write residual DEA and any nitrosamine testing you require.
- Write amide assay, free amine, and color.
- Keep a foam test as a separate line.
- Do not substitute CMEA when the formula was built on CDEA without a new curve.
Use this with the CDEA versus shampoo note and what is amidification for how the amide is made.