Japan Wax
Saponification values, fatty acid makeup, and what this oil does in a bar of soap.
Saponification values
Grams of lye needed to saponify one gram of japan wax. Multiply by your oil weight, then apply your superfat.
- NaOH (bar soap)
- 0.153
- KOH (liquid soap)
- 0.215
- Iodine
- 11
- INS
- 204
Fatty acid profile
These figures account for 92% of japan wax. The remainder is made up of fatty acids this model does not track, so treat the derived qualities below as indicative rather than complete.
| Fatty acid | Percentage |
|---|---|
| Palmitic | 80% |
| Stearic | 7% |
| Oleic | 4% |
| Myristic | 1% |
Soap qualities at 100%
What a bar made entirely of japan wax would score. Almost nobody soaps a single oil at 100% — this is here so you can see what the oil contributes to a blend. The shaded band is the range most makers aim for in a finished recipe.
What that means in a recipe
Contributes a lot of hardness (88), so it firms a bar up and helps it unmould cleanly and last in the dish.
Derived from the numbers above rather than written by hand, so it stays in step with the data. Tendencies, not guarantees — your oils, water, and technique all move the result.
Oils that behave similarly
Closest matches by fatty acid makeup — the usual starting point when you have run out of japan wax and need a substitute. Check the lye maths again after swapping: SAP values differ even between oils that behave alike.
- Palmitic AcidSAP 0.153 NaOH
- Palm StearinSAP 0.142 NaOH
- Palm OilSAP 0.142 NaOH
- Red Palm ButterSAP 0.142 NaOH
- Ghee, any bovineSAP 0.162 NaOH