Black stain on collar - goatskin A2 flight jacket.

[gary]

Hi Roger

I noticed a black stain on the inside of the collar. It only really shows when the light is right. It doesn't seem to be oily or greasy but I suppose it was caused by sweat. What do you suggest for cleaning?

Thanks,

Gary

http://i1132.photobucket.com/albums/m572/turner_gary/2011_03300210.jpg

http://i1132.photobucket.com/albums/m572/turner_gary/2011_03300209.jpg

[Roger Koh]

This is some stain that we should not over clean it as the finish may have been weaken from this soiling contamination and may reveal any damages after the camouflaging stain is removed; nor do we under clean it.

Finish identification will help us determine the proper selection of the most suitable process to remove them safely. Therefore an absorbency test with a drop of water to the stain and to the surrounding areas to determine how they response will be the first step.

Show us some test pictures and I shall explain further from there…

Roger Koh
[email protected]
Tomorrow’s leather care Technology delivered Today!

[gary]

The first picture is 5 minutes after putting 3 drops, one above the stain, and two on the stain. They are the same as when I first put them.

http://i1132.photobucket.com/albums/m572/turner_gary/2011_03310211.jpg

The next one is 15 minutes later (20 min total). The drop above the stain is partially absorbed,
but the two on the stain have been completely absorbed to become invisible.

http://i1132.photobucket.com/albums/m572/turner_gary/2011_03310213.jpg

This one is also at 20 minutes, and in better focus.

http://i1132.photobucket.com/albums/m572/turner_gary/2011_03310212.jpg

[Roger Koh]

The test shows that the topcoat is partially damaged and ought to be replaced after complete removal of the sweat stain. At this point we do not know if the colorcoat has also been weaken and care should be taken so as to avoid over cleaning it and removing the weaken colorcoat at the same time.
The recommended cleaning process is as follows:

Step-1 Gentle Cleaning:
Use Cleaner-3.8 > Rinse-3.0.
Test clean by applying Cleaner-3.8 onto the horsehair Brush-1, agitation and extract with towel avoiding the rubbing action. Dry with hair dryer to inspect soiling appearance. If not satisfactory repeat, otherwise proceed to the next step.

Step-2 Prep Cleaning:
Use Prep-7.7 > Cleaner-3.8 > Rinse-3.0
Test clean as above step 1. All surface stain should be gone; however has to be gentle as not to remove the weaken finish; otherwise color refinishing is inevitable.

Step-3 Degreasing:
Use Degreaser-2.2 > Rinse-3.0
When Prep-7.7 cleaning reveal that colorcoat is damaged and stain is penetrated; Degreasing is necessary to remove stains from within the leather structure.

Step-3 Leather Rejuvenator:
Use Hydrator-3.3 > Fatliquor-5.0

Step-4 Topcoat Refinish:
Use Micro Topcoat-72S (satin) or a mix of gloss and matte to match original luster. Hopefully no weaken colorcoat is removed during the cleaning process.

Here’s the Semi-Aniline Kit-SA3, products mentioned not found in this kit can be add-on to it.


http://i300.photobucket.com/albums/nn4/Rogerkoh/Semi-AnilineKit.jpg
Leather Doctor® Semi-Aniline Leather Care Kit-SA3


Contents:
Prep-7.7 - 60ml
Cleaner-3.8 - 250ml
Rinse-3.0 - 250ml
Leather Scent-B - 120ml
Hydrator-3.3 - 250ml
Fatliquor-5.0 - 250ml
Leather (horsehair) Brush-1 - 1pc
3” Poly-Brush® - 1pc
Washable Rags - 5pcs


Roger Koh
[email protected]

[gary]

Hi Roger,

Here are photos taken after cleaning with Cleaner-3.8 and Prep-7.7. It looks about the same to me. I can't really tell whether the stain is only on the surface. I have the impression that has not penetrated, because only the "tops" of the texture are black, not the fissures between them. You can see that somewhat in the photos but under a magnifying glass it's very apparent.

Thanks,

Gary

http://i1132.photobucket.com/albums/m572/turner_gary/2011_04160218.jpg

http://i1132.photobucket.com/albums/m572/turner_gary/2011_04160219.jpg

[Roger Koh]

Place a drop test of Prep-7.7 onto the stain and leave it to dwell about an hour thereafter Clean off with Cleaner-3.8 using horsehair detail Brush-1 for agitation and towel extraction follows by rinse.

If the result is not satisfactory, place another drop on the same location and let it dwell overnight; thereafter cleaning, extracting and rinsing as above.

Show us the result and we can go further from there...

Roger

[gary]

Hi Roger,

The previous two pictures had been taken after letting the Prep-7.7 dwell for about 20 hours, followed by Cleaner-3.8 and Rinse-3.0. This was done over the entire stain. The result looks to me to be about the same as before the treatment.

Regarding my remark about only the tops of the grain texture being stained, but not the area between them, I think that may be because the finish has worn off the tops, allowing the stain in. The finish is still intact between the tops, keeping the stain out there.

Gary

[Roger Koh]

I think that may be because the finish has worn off the tops, allowing the stain in. The finish is still intact between the tops, keeping the stain out there.

Gary

If what you say is true, a stretch or light abrading test will lighten up the worn off tops to confirm that the finish is gone.

Otherwise, Degreaser-2.2 > Rinse-3.0 is the next procedure to test it out prior to optional color coat > topcoat.

Tips:
Use a wooden icecream stick to do the light abrading test.

Roger Koh
[email protected]

[gary]

Hi Roger,

I tried agitating a dime sized spot with Prep-7.7, using a smoothed end of a bamboo skewer. The photo below shows this, marked by the black tape. You can compare to previous photos noticing where the stitching comes closest to the leather. I was surprised to see that it brought out the stain much more in that spot. Only a few tiny particles of black showed on the cloth used to wipe it afterwards, along with a slight amount of brown color.

http://i1132.photobucket.com/albums/m572/turner_gary/2011_05050226.jpg

[Roger Koh]

Is the cleaned spot you show still wet or it has already been dried?

Look's like it is still wet when this picture is taken...

If it is dry, have you use the same bamboo skewers to stretch one of the black grains to see if it lightens – if so the finish may have been gone and the absorbent exposed structure may have been saturate with body oil, grease and sweat, through these absorbent stain areas.

To degrease it, Degreaser-2.2 > Rinse-3.0 will do a better job. Hydrator-3.3 is another product that will move the foreign contamination within the structure to wick-up clean prior soften it with Fatliquor-5.0 thereafter. It is then ready for the next phase of adhesion-coat > color-coat > top-coat repair