Is the stain on the seat or on the back cushion?
It is most likely a dyes stain.
It could also be a rust stain from partial removed bloodstain, if it is on the seat.
This is the recommended procedure for unknown stain.
Dye stain removal > tannin stain removal > tarnish stain removal.
All dyes will response with Prep-7.7 > Bleach-9.9
All stains that derived from plants and vegetables will response with d’Tannin-3.5
All metallic stains like the iron ions from blood will response with d’Tarnish-1.3
See this problem-solving guide for auto perforated leathers.
Leather-Safe Problem Solving Guide (P.p) – Perforated Leathers
The below is the recommended kit with optional d’Tannin-3.5 and d’Tarnish1.3 as add-on
Kit P7.di (Auto Perforated Leather Dye / Ink Remover Kit)
Leather Doctor® Kit P7.di is an innovative system developed to remove dye and ink stains from perforated leathers. This novice “reverse-transferring” technique utilizes Prep-7.7 that is squeeze through a paper towel. Prep-7.7 works by penetrating, lubricating and suspending the stains and is continuous wick through the more absorbent paper towel. Residual stains if any is further work by boosting Prep-7.7 with Bleach-9.9. Sticky residue is removed by Cleaner-3.8 follows by Rinse-3.0 and neutralized by Acidifier-2.0. To return the leather to softness, Hydrator-3.3 preconditions it prior to Fatliquor-5.0 replenishing. Micro Top-54M topcoat refinishes is an option and Protector-B+ imparts a non-stick rub-resistant protection with a buttery feel. Note that the product suffix number denotes its pH value in a leather-safe stain removal holistic system.
Like to give it a try?
Roger Koh
[email protected]