What ingredients tend to cause acne?

I realize few of us are dermatologists, but I'm curious whether anyone with some knowledge on the subject can talk about what ingredients you might find in after shave products (or shave soaps, even) which have the potential to cause acne, blemishes, or otherwise be comedogenic.

I'm prompted to ask since I'm seeing minor pimples here and there on my cheeks and neck, even more than a week into shaving exclusively with my skin-friendly OneBlade, which leaves me irritation-free. I'm wondering whether an ASB or other product might be leading to these small blemishes. Any thoughts? FWIW these are more the mild, minor, pink and soft blemishes, rather than the rougher pimples I remember from adolescence.

Cocoa butter and coconut oil are big time offenders. It's part of the reason I don't use either in Bufflehead.

Cocoa butter and coconut oil are big time offenders. It's part of the reason I don't use either in Bufflehead.

I've heard both of these mentioned in the past. Is coconut oil still a problem if it's saponified? It's used in a number of classic shave soaps (MdC among them, I think), and I'm wondering whether it's actually problematic there.

Cocoa butter and coconut oil are big time offenders. It's part of the reason I don't use either in Bufflehead.

I've heard both of these mentioned in the past. Is coconut oil still a problem if it's saponified? It's used in a number of classic shave soaps (MdC among them, I think), and I'm wondering whether it's actually problematic there.

It is not. Cocoa butter, on the other hand, remains a problem because its unsaponifiable components are the components that are comedogenic (cause acne).

Good to know, thanks Barrister_N_Mann. Now I'm wondering if it's the dimethicone in the Nancy Boy ASB that's been causing trouble for me recently. That'd be a shame; I love how that stuff smells.