@Mobjack Bay I came over here from Basenotes as well
Wanted desperately to become an independent natural perfumer but rose, sandalwood, jasmine are so fundamental to scent creation and SO EXPENSIVE, so started doing soap because of its propensity for cheaper essential oils.
To speak to the points re: soap and perfume raised by
@ResolvableOwl and
@Mobjack Bay, I found and attached a page in "An Introduction to Perfumery" by Tony Curtis and David G Williams 2nd ed, 2001 (someone told me this was the textbook they use in Grasse but don't quote me on that) - one of the 4-5 pages dedicated to soap in the whole book (!) that touches briefly on the issues with aromachemicals and their diffusion, discoloration, and degradation in soap.
I have yet to come across a really good resource for the intersection of soap and perfume. The soap books talk about perfume for a couple of pages, while the perfume books talk about soap for a couple of pages. We need depth, people!
I also dug around and found my copy of "Perfume" by William I Kaufman, 1974, which has a set of the Jean Carles charts and I am attaching them to this msg as well, tho they are slightly updated from the ones I linked to above. These charts are more granular. Truthfully I prefer the earlier charts as they are more concise, but the method is the same. The vertical columns are studies in contrast, and the horizontal rows are studies in similarities. Apologies for harping on the charts, but I did the natural materials study (thanks libertynatural.com) a few years ago and it
changed my life lol. Have been slowly collecting the synthetic aromachemicals (thanks creatingperfume.com) and hope to start that study soon.
Regarding fixative EOs for soapmaking, I've had the best luck with Atlas cedar, clary sage, patchouli, benzoin, and ylang-ylang (canaga, which IIRC comes from the last presses of ylang-ylang is a standard fragrance material for soapmaking).
The top/middle/base pyramid can get all turned around in soap. Like the citrus notes are top notes in perfumery but in soap orange stays forever, lemon has so-so sticking power, and Bergamot .. forget about it!
Tried for a while to find a nice rosemary-mint blend where the rosemary doesn't disappear completely, one day I threw some Atlas Cedar in there and voila! The rosemary stuck around. I've since found Atlas Cedar to be an unobtrusive all-around fixative for me when I do herbaceous/agrestic blends. I don't have to be too careful with % and it's cheaper than clary sage. But clary sage is lovely, and sometimes you really need it.
Meanwhile ylang-ylang and geranium are considered middle notes in perfumery but for me in soap they have fixative properties and can stick like hell. I've also had good luck with lavandin, classified as a top/mid-note, but it sticks much better than lavender and seems to act as a mild fixative for lemon.
Sometimes I'll use a FO like WSP's Sandalwood and blend it with EOs. Am hoping to someday stumble upon an original FO/EO blend that packs a punch.
What have you guys discovered to work for you as fixatives? Have you found upon any EO or FO/EO blends that really work for you or do not work for you in soap?
Edit:
@ScentimentallyYours that book looks so good. Thank you for the link. Buying it now...