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dima
03-19-2015, 07:32 AM
Hi, could you please help to find the right procedure to remove the stains on these aniline leather cushions? I'm not sure about their origin. My guess is wine or coffee? They are not throughout the leather (nothing on the back side). I washed these cushions in the dishwasher + water solution and a lot of dirt came out. Color became lighter and cushions are cleaner, but the stains are still there. Thanks

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Roger Koh
03-19-2015, 12:33 PM
Leather identification will then determine which Leather Problem Solving Guide to be used as reference so that the end result will retain its original characteristic. Picture 4 shows a typical “Nubuck”. Nubuck is aniline leather that has its surface buffed or sanded to produce a finger writing effect with very fine naps. Pictures show that this is a standard nubuck other than oil or wax pull-up types. More pictures of unused bigger area may confirm this leather type. Meanwhile refer to this Nubuck (N) Leather Problem Solving Guide.

4828

>>> My guess is wine or coffee?

Wine, Coffee, Tea, Juice, Beer and all stains derived from vegetables and plants is under the same stain type category in the Nubuck (N) Leather Problem solving guide.
Since the leather has been clean as described we may go straight to “step 3” and product used is d’Tannin-3.5.
Spot cleaning test is done with a cotton swab to just a spot to see how it response.
The stain is saturated and agitated and when cotton swab pick up soiling it is repeated until the cotton swab turns clean. It is let to slow natural dry for redox or reduction-oxidation chemical reaction to take place. Inspection is done when dry to evaluate if we have guess the right stain type.

Picture 4 shows the stain has an outer darker stain and this is characteristic of a bloodstain.
Bloodstain is a compound stain and the protein component is first removed follows with removing the iron stain.
Refer the stain removal steps from the chart:
Protein stain is first removed with d’Protein-10 using a small spatula or a bamboo skewers with a flat tip to loosen the coagulated protein stains (protein stain is the most stubborn stains as it binds with the protein leather fibers tenaciously). When released stain is pick up until it shows clean with satisfaction the high pH d’Protein-10 (pH value 10) has to be mandatory pH balanced with Acidifier-2.0 (pH 2.0) to return the leather to its pH neutral, isoelectric-point or pI (3 – 5). When dry the remaining dark outer rings is further treated with d’Tarnish-1.3. d’Tarnish-1.3 works by redox or reduction-oxidation chemical reaction and the result is inspected when the stain is dry. d’Tarnish-1.3 (pH 1.3) need to be pH balanced with Basifier-8.8 when it dries and stain satisfactorily removed.

Roger Koh
04-08-2015, 03:37 PM
Please have your feedback and we go from there!