Pigmented (Micro or Semi-Aniline) - Semi Aniline Seat Stains

[Oxford_Brian]

Hi Roger.

Hopefully these images will upload. I think its a Semi Aniline chair and the stain is from a sauce or gravy. It is present for a long time (months at the minimum). It has been very much absorbed into the surface. Do you think it is gone beyond cleaning? I have used some leather cleaning products on it but it made no difference.
Thank you in advance
Brian

[Oxford_Brian]

So far, I have tried these. I keep my kit for special occasions! ( I do apologise for the photo quality. They are from my phone. )

[Roger Koh]

>>> I think its a Semi Aniline chair

Use this Aniline (A.s) – Semi, Leather problem Solving Guide as reference.



>>> and the stain is from a sauce or gravy. It is present for a long time (months at the minimum).

When looking for “Stain Type”, sauce or gravy with tannin or coloring derived from vegetable or plant would fall onto the Tannin-Based category.
Accordingly, the products used as 1st step would be d’Tannin-3.5 follows with Rinse-3.0 to remove the stain and Hydrator-3.3 > Fatliquor-5.0 system to restore the suppleness of the leather with Protector-B as a rub-resistant protector.

However, since it is aged, oxidation may have taken place and makes the stain removal not easier when it is fresh.


>>> It has been very much absorbed into the surface.

It is understood that below surface product penetration, lubrication and suspension is vital to release the stain to the surface, and this will take the form of hydrating it below surface, and reverse transfer the stain to an absorbent towel, instead of still remaining on the surface.
In theory, unknown stain may be removed by light cleaning using ‘Clean-3.8’, heavy cleaning using ‘StrongClean-4.3’ or greasy cleaning using SuperClean-4.9 according to the guide.


>>> Do you think it is gone beyond cleaning?

Traditional surface cleaning may not work as you have mentioned that the stain has penetrated.
The cleaning has to go deep into the leather structure where the stain lies.
In practice, saturate a facial cotton pad with ‘SuperClean-4.9’ lay on the stain and cling wrapped with food wrapper to control evaporation for up to 72 hrs and keeping it constantly wet to see if any stain is reverse transfer.


>>> I have used some leather cleaning products on it but it made no difference.

Improve the technique and see whether the stain moves.

This is tips is from your existing products, before we discuss how we can use Hydrator-3.3 to move the stain from below more efficiently.

The last resort is with d’Tannin-3.5 working on a reduction-oxidation (redox) principle to get rid of the tannin coloring.

Roger Koh
Leather Care System Formulator / Practitioner / Consultant / Instructor / Coach

[Oxford_Brian]

Thank you very much, Roger. I am trying the cotton pad soaked with Superclean 4.9. I still have a lot of this kit left (perhaps about 40% of products)
http://www.leathercleaningrestoratio...nk-Dye-Kit-Ap4

If there is anything else in there I can use, just let me know.

[Roger Koh]

Since you have the Kit-Ap4, we will make use of the towel to do a ‘reverse transfer’ technique with SuperClean-4.9 a milder version than Prep-7.7 not to over clean the stain by leaving any undesirable lightening effect especially with presence of aniline dyestuff, There is no such fear of a lightening effect if the leather is semi-aniline or micro-pigmented, so using SuperClean-4.9 with a pH value of 4.9 is closer to the leather average pH of 4. Prep-7.7 is pH 7.7 and may affect the pH sensitivity of aniline dyestuff if any.
This reverse transfer technique applies to the entire seat from edge to edge with the Towel-T5 from the kit while concentrating on the stain with SuperClean-4.9 and feathering it out to avoid any ring when dry for a more even appearance.

Instruction:

1 – Shake well and applied SuperClean-4.9 by FoamBrush-3 to achieve an even appearance.

2 – Apply Towel-T5 to the entire surface by spraying SuperClean-4.9 to wet it and stretch over with the help of horsehair Brush-1 working out any air bubble (please show some pictures you are doing it right).

3 – Cotton Pad mentioned is used as a reservoir concentrating on the stain.

4 – To control evaporation use food cling wrapper or equivalent to cover it.

5 – Let it dwell up to 72 hours with in between inspection, making sure any dryness is replenish instead with Hydrator-3.3 to keep the surface hydrated and for structural water movement for suspended soiling to resurface.

6 – Check out if stain is reverse transfer by lifting off the cotton pad during interval inspection.

7 – Remove the entire preparation once inspection reveal the stain is reverse transfer and gone.

This technique will give the best result in stain removal appearance almost seamless, however it also depends on the penetrating, lubricating and suspending power of the SuperClean-4.9, otherwise we need to change to a more suitable stain removal system to match the stain type with d’Tannin-3.5 reduction-oxidation (Redox) reaction system. Wicking or bringing the already suspended stain depends very much on Hydrator-3.3 otherwise it remains stuck within the leather fiber structure.
Like to see some pictures you are doing it right.

Any question you may have?

Roger Koh
Leather Care System Formulator / Practitioner / Consultant / Instructor / Coach