Pictures show besides the surface blacken stain; it also show that the stain has penetrated through these perforations holes into the leather structure and wick-up, trap beneath the leather finish layer as the secondary stain. The third brownish color stains appears around the perforation holes too, and this may be what the color is beneath the leather finish blue layer.
Further diagnosis may be helpful before we can prescribe the appropriate product and sequence of procedure to remove this stain safely.
1] Smell - can any musty odor be detected, besides others?
If musty odor is detected, then the black stain is mold growth. Cleaning and fungicide treatment may not remove these stains completely as they are sunken pits and only rectified with matching color pigments.
2] Tacky or slimy – when run with wet tap water, is the feel the same on stain and non-stain area?
If stain area tackiness or sliminess is detected then its due to alkalinity that need to be rectified with a pH 2.0 acidifier to revert the finish back to a healthy squeak.
Tips:
As the age of the stain is unknown and type is only a guess; it would be wise not to over clean it in a hurry as the vulnerable stain finish may be removed.
Assuming the test 1 and 2 above are negatives and ruled out; the recommended procedure is as follows:
Step-1 Test Removal of Surface Blacken Stain:
Use Cleaner-3.8 (pH 3.8) test clean with cotton swab to see how the blacken stain response and also the strength of the finish if it’s been transfer to the cotton swab. If color transfer to the cotton swab, color refinishing is inevitable. When there is no response to the blacken stain, switch to Prep-7.7 (pH 7.7) and test again if the blacken stain is removed, with or without any color transfer.
Step-2 Actual General Surface Blacken Stain Removal:
From the above test Cleaner-3.8 is the weaker removal and Prep-7.7 is the stronger removal for the blacken stain. Cleaner-3.8 is to be followed by Rinse-3.0 and Prep-7.7 remaining sticky residue is to be removed by Cleaner-3.8 follows by Rinse-3.0.
Tips:
See Leather-Safe Problem Solving Guide-AP9 - Auto Pigmented Leathers for procedure of other stain types.
Step-3 Coffee Stain Removal:
The tannin color that is found in coffee is to be removed by a specialty stain remover using d’Tannin-3.5
This product is sprayed and worked into the perforated holes to saturate the entire stain area and leave it natural dry.
When dry it is rinse with Rinse-3.0 and thereafter inspection to see if appearance improve, otherwise repeat.
Step-4 Hydrating:
The entire panel is to be hydrated through these perforation holes into the leather structure soak damp and cover with see-through plastic cling wrapper to prevent evaporation. This overnight dwelling allows the stain beneath to be suspended and redistributed. The plastic covering is removed, wick-up stains is extracted with terry towel until towel shows dry. Fresh Hydrator-3.3 is reapplied and this time absorbent paper towel is place on top, spray wet it and makes it an extension of the leather surface without any air bubbles in between. This second treatment is to trap further wicking of the residual stains onto the absorbent towel. This process is repeated until the tannin is completely removed from beneath the color finish by towel extraction and wicking-trapping with paper towel.
Tips:
A heavy towel can be used to weight the paper down during the normal drying process.
Step-5 Fatliquoring:
This process is using Fatliquor-5.0 working with the foam brush into the perforated holes reaching the leather structure fibrillary system to soften and strengthen the leather when dry.
Step-6 Non-Stick Rub-Resistant Protection:
Use Leather Scent-B.
I will be please to answer questions!
Below is the guide, maintenance cycle and the care Kit-AP3, individual specialty products available as add-on from this link: http://www.leathercleaningrestorationforum.com/forum/showthread.php?t=360
Roger Koh
[email protected]
http://i300.photobucket.com/albums/nn4/Rogerkoh/AutoPigmented-PSG1.jpg
A leather-safe Problem Solving Guide-AP9 for Auto Pigmented Leathers
http://i300.photobucket.com/albums/nn4/Rogerkoh/AutoPigmentedKit-AP3.jpg
Leather Doctor® Kit-AP3
Contents:
Prep-7.7 - 60ml
Cleaner-3.8 - 250ml
Rinse-3.0 - 250ml
Hydrator-3.3 - 250ml
Fatliquor-5.0 - 250ml
Leather Scent-B - 120ml
Leather Scent-D - 120ml
Leather Brush-1 (horsehair) - 1pc
3” Poly-Brush® - 1pc
Washable Rags - 10pcs
Individual refill available in larger package or concentrates
Email for details:
[email protected]
Prep-7.7
This is a pH 7.7 aqueous high viscosity leather preparatory cleaner for Pigmented leather types. It’s developed to strip foreign soil accumulation to its original finish. It works by dwell-time allowing its superior penetrating, lubricating and suspending power to do its work. Besides it's also used in the leather-safe dye and ink stains removal for: Grease based ink stains like ballpoint ink. Water based ink stains like stamp pad ink. Dye transfer stains like blue jeans, leather, ink print and newsprint. It is highly recommended that the remaining sticky residue is thereafter removed in conjunction with Cleaner-3.8 and Rinse-3.0 as a holistic leather-safe.
Cleaner-3.8
This is a pH 3.8 all purpose leather-safe anionic cleaner that is particularly effective in emulsifying oily soils and in suspending particulates. It works by penetrating, lubricating and suspending soiling safely and effectively through gentle chemical reaction; working in perfect harmony with all leather constituents that include the tanning agent, preservative, dyestuff and especially the fatliquor. It's for all leather types including: Pigmented, Aniline, Vachetta, Nubuck and Suede.
Rinse-3.0
This is a pH 3.0 aqueous leather-safe rinse to neutralize harmful alkaline and perspiration residues; for stabilizing and strengthening leather constituent pH chemistry integrity. It's for Pigmented, Aniline, Vachetta, Nubuck and Suede leather types.
Hydrator-3.3
This is a pH 3.3 aqueous leather-safe hydrator. It’s for hydrating dried, stiffed or shrunk leathers (to separates the crushed, stick together fibrils and relax them) prior to strengthening and softening with Fatliquor-5.0. And it’s also used for facilitating colloidal water movement within the leather structure capillary motion during the wicking process. That will cause suspended soil particulates to be moved to the leather surface to be extracted with absorbent towel while damp and erase with Leather Eraser-4 when dry. It’s for all leather types including: Pigmented, Aniline, Vachetta, Nubuck, Suede, Hair-on-Hide and Woolskin.
Fatliquor-5.0
This is a pH 5.0 anionic charged micro emulsion fatliquor leather rejuvenator. It’s for replenishing original fatliquor that diminishes thru sun-bleaching, ageing, heat and alkaline exposure or cleaning. It penetrates and lubricates the leather fibers so that after drying they will be capable of sliding over one another smoothly. Besides softening the leather with stretchability, compressibility and flexibility; fatliquor enhances its rip tensile strength greatly. Relaxes coarse breaks, creases and wrinkles to provide drapes, suppleness and prevents cracking. It helps to keep leather at its optimum physical performance and prevent premature ageing. It’s for all leather types including: Pigmented, Aniline, Vachetta, Nubuck, Suede, Hair-on-Hide and Woolskin.
A Fatliquor video by Discovery Channel: http://videos.howstuffworks.com/discovery/28309-dirty-jobs-fat-liquor-video.htm
Leather Scent-B
It’s a tactile buttery-feel for Pigmented and Aniline leather seats. This is a non-film forming, non-stick rub-resistant protector that enhances a soft natural buttery-feel with a classic leather scent. It’s for imparting a non-stick breathable barrier essentially to shield the detrimental effects of sticky soiling including the nasty ballpoint ink. And for helping to release those tenacious dye-transfers stains especially on light colored leathers easily without resorting to unnecessary color refinishing. Its natural buttery-feel protection increases the leather resistance to wet and dry rubs, thus reduce stretch, scuff and abrasion. And it reduces friction squeaks that wear the finishes when leather is rubbed against during movement. Or friction that wears the leather finishes caused by getting in and out of auto.
Leather Scent-D
It’s a tactile draggy-feel for Steering Wheel. This is a non-film forming, non-stick rub-resistant protector that enhances a draggy-feel with a classic leather scent. It imparts a non-stick breathable barrier essentially to shield the detrimental effects of sticky soiling including the nasty ballpoint ink. And it does help to release those tenacious dye-transfer stains especially on light colored leathers easily without resorting to unnecessary color refinishing. Its natural draggy-feel protection increases the leather resistance to wet and dry rubs, thus reduce stretch, scuff and abrasion. It is also used as a scuff repairer, filling and concealing surface scuffs to improve appearance. The drag produces an unforgettable familiar sound sweet to the ears when leather is rubbed.
Advanced Auto Leather-Safe Maintenance System
1st-Cycle
Step 1: Start new leather Preventive Maintenance with a Non-stick & Rub-resistant Protector.
This initial preventive measure for new car is to ensure that the topcoat is first protected against the detrimental effect of sticky soiling, including dye transfer from clothing and against the wearing out from sliding in and out of car. Scent-B is recommended for the seats to impart with a natural smooth buttery-feel; while else Scent-D is recommended for steering wheel and gear shift knob imparting with a natural draggy-feel for a safer anti-slip grip; both enriching the senses with the unforgettable classic leather scent. These odorless versions are also available as Buttery Feel-76 and Draggy Feel-79. Optional to the tactile feel is also available in waxy and silky feel; both infused with leather scent or come as odorless.
This sequence of non-stick, rub-resistant topcoat protection is performed by first cleaning with a leather-safe pH 3.8 cleaner, follows by a pH 3.0 rinse, then protected with the Scent-B/D when dry, thus: Cleaner-3.8 > Rinse-3.0 > Leather Scent-B/D.
Step 2: Neutralization for pH Control.
This pH neutralizing preventive measures is recommended to control sweaty body contact, which may contain traces of urea from shifting alkaline by the natural bacteria from the environment. Resulting is tackiness to the leather surface when dry and sliminess when wet from alkaline over exposure.
This sequence of pH neutralizing is first performed by towel rinse with a leather-safe pH 3.0 rinse that imparts a momentarily refreshing fragrance, then follows with Scent-B/D protector when dry, thus: Rinse-3.0 > Leather Scent-B/D.
Step 3: Sanitization for Odor Control (optional Sanitizer-3.9 as an add-on).
This sanitizing routine preventive maintenance or as needed after a sweaty ride is to control the activities of the odor causing bacteria from attacking the sweaty surface contamination hygienically clean and odor free.
This sequence of odor controlling is performed by first appllying with a leather-safe pH 3.9 sanitizer and towel off to dry, thereafter with Scent-B/D, thus: Sanitizer-3.9 > Leather Scent-B/D.
2nd-Cycle
Step 4: Periodic Maintenance.
This will be a repeat similar to Step 1, on a quarterly to a half-yearly basis depending on usage. It’s then followed by Step 2 and 3 similar to 1st-Cycle.
3rd-Cycle
Step 5: Restorative Cleaning
This recommended yearly to 2-yearly restorative cleaning cycle is necessary to remove all foreign contaminated residues, including the age-old, build-up of protector if any; stripping it down to its original OEM leather topcoat. It’s to prevent surface build-up that may distort the original aesthetic and tactile-feel characteristics of the leather. This sequence of restorative cleaning is performed by using a pH 7.7 leather prep to do the delicate chemical reaction of penetrating, lubricating and suspending foreign surface contamination, with its ability to slowly dwell it out safely. It is then followed by the removal of its sticky residue with the leather-safe pH 3.8 cleaner and rinsing with a pH 3.0 rinse to a healthy squeaky clean. It is also the time cycle to look at the beautiful but weak perforated panels, including those needle holes and seams. These weak areas unlike the protected surface are vulnerable to absorbing cleaning solution, that when wet and dry again may cause stiffness to the leather, and when compress, stretch or flex may result in premature cracks. A leather-structure preventive maintenance is to keep these weak areas perpetually soft and supple by rejuvenating it. Rejuvenation involves a leather-safe pH 3.3 hydrator to relax the stick together fibrils, separating them to prepare for effective fatliquoring; besides it’s to purge penetrated foreign contamination by the wicking process and balance the chemistry integrity within the thickness of the leather structure. Fatliquor is derived from especially ionic charged natural fat, oil and water use in tannery worldwide. The tannery leather moisture content when dry to the touch has an average of 14% and it’s mainly derived from this fatliquor - the life-blood of leathers. The main function of the fatliquor is to lubricate these leather fibrils acting like millions of interconnecting hinges, so that they can slide over one another smoothly without breaking with softness, suppleness and strength; thus prevents premature ageing to the leather from dryness, stiffness and cracking.
This process follows in this sequence: Prep-7.7 > Cleaner-3.8 > Rinse-3.0 > Hydrator-3.3 > Fatliquor-5.0 > Leather Scent-D. This 3rd-Cycle will be continued by Steps 2, 3 and 4 and the cycles go on.
4th-Cycle
Step 6: Topcoat Repair (optional Topcoat Micro-72 Gloss/Satin/Matte as an add-on)
The objective of the topcoat is to impart a film forming coating that provides abrasion and stain resistance to the colorcoat. It is this topcoat that decides its desired luster of gloss, satin or matte. Without this topcoat, the color basecoat would be: a) poor in aesthetics such as appearance and feel; b) susceptible to sticking together or attracting loose dust and dye especially in hot humid climate region; c) poor physical properties such as wet rub, sweat resistant and scuff resistant; d) poor in ageing properties such as soil resistant and wet cleaning resistant. It may be desirable to repair the topcoat especially to the heavy wear areas especially to the two front seats.
This process follows in this sequence: Prep-7.7 > Cleaner-3.8 > Rinse-3.0 > Topcoat Micro-72 gloss/satin/matte > Leather Scent-B. This 4th-Cycle will be continued by Steps 2, 3 and 4 and the cycles go on.