The leather is absorbent to have such penetrated stain, most likely it is aniline and could be semi-aniline; will need better pictures of a test with Stripper-2.2 to confirm.
Any way they can be salvage, as you can see in other threads, head oil, grease and sweat contamination is very common on leathers; including urine stains.
The finish is already damages that will require a refinish after the decontamination cleaning.
Degreasing Headrest:
1] Degreaser-2.2 > Rinse-3.0.
These two steps system will remove the contamination.
Urine Stain Decontamination
1b] d’Urine-2.2 > d’Protein-10 > d’Urine-2.2
These three steps decontaminates the urine stain.
2] Hydrator-3.3
This step further removes suspended soiling from the leather structure and precondition the leather for fatliquor replenishing.
3] Fatliquor-5.0
This step soften and strengthen the leather when dry.
4] Color Repair to match existing finishing
5] Topcoat to match existing finishing
6] Rub-resistant Protection
Let me know how far you want the job to be done,
The finish type need to be positively identified to discuss about the refinishing process, it is either aniline or semi-aniline. If it is aniline mostly likely you may have to go a darker color to camouflage especially the urine stains.
Roger Koh
[email protected]
For your further reading:
Degreaser
Degreasers are specialty leather cleaning agent that may be solvent-based or water-based; formulation are available in both liquid spray and direct gel application. It is designed to be used primarily on heavy penetrated oily, greasy and sweaty soiling derived from skin and hair contact. Dwell time is one of the essential fundamental for effective soil suspension to take effect. Solvent-based comes in the form of aerosol spray as well as gel type. These products extract the oil and change it into powder residue to be vacuumed thereafter, and the remaining gel removed with solvent-based related products; besides the indirect cleanup mess, health and fire hazard is another consideration. The water-based pH specific type functions as an emulsifier, transforming the contamination milky in color for direct towel extraction; follows with an acidic matching rinse to complete the degreasing process. This acidic water-based system helps with bleeding control and simultaneously charging the protein fiber ionic positive, for a more effective hydrogen bonding with the other ionic negative charged leather constituents like dyestuff and fatliquor; thus stabilizing the chemistry integrity of the leather while removing foreign contamination. In most degreasing situation, existing fatliquor or natural oils are inevitably removed to a degree and leather rejuvenating for suppleness and strength is accomplished by proceeding to hydrating and fatliquor replenishing it. Protective latex glove is recommended, as almost all degreasers will remove oil from our skin as well. For the solvent-based types, a dust and mist mask is recommended during the process from breathing the airborne mist or dust.
Rinse
Rinse is aqueous solution that has a pH range of 2 to 4, design for removing residues after degreaser or cleaner. Browning or resoiling can occur without first removing the remaining residue. Effective rinsing will result in a squeaky-feel, free of suds feeling. Rinse is also used in routine cleaning to neutralize perspiration residue from browning the leather or turning it sticky.
Stain Remover - Protein
Protein cleaner is usually an alkaline solution design for removing protein stains. Protein stains like milk, blood, etc. has the tendency to coagulate with the leather protein fiber. It would require a protein cleaner to swell the stains in order to release it. It is highly recommended that alkaline cleaners are neutralized with an acidic counterpart thereafter, example would be using an acidifier, tarnish or urine remover when it has accomplish it purpose of specialty soil removing.
Odor Killer - Urine
Urine is a waste discharge from human or animal, besides the typical coloration it has the uric acid and the ammonium salt to deal with. When deposited urine attracts the natural bacteria from the atmosphere and starts to ferments, a putrid odor will develop from the protein component of the urine and ammonia odor will develop from the ammonium salt. When ammonia odor is detected, the pH of the contamination would have shifted above 10. Such high pH above the neutral average 3 to 5 of leather causes the leather protein fiber to shift ionic negative (-ve); that causes the leather to repels its other ionic negative (-ve) constituents like the tanning agent, fatliquor and dyestuff. Animals especially cats have the tendency to deposit on the same spot. The heat on the old deposit tends to leach out the tanning agents that manifest as darkening stain, while the leach out fatliquor appears as whitish powdery residue. In such severe situation, quite often the leather turns slimy and may show signs of damages. The best approach is to treat it with a low pH acidic ammonia neutralizer, to help dissolve the urine salt and slow down the bacteria activities. Such acidic treatment will help neutralize the ammonia alkalinity; simultaneous ionic charges the leather protein fiber positive to stabilize the leather chemistry, and retards bacteria activity from off gassing putrid odors. Remaining protein components are removed by using a leather protein stain remover follows with a second acidic treatment to neutralize the alkalinity once again for the sake of the leather chemistry stability. Another approach is by treating the area with culture bacteria; with the logic that the cultural bacteria will consume the food source in the urine thus eliminate the source of the putrid odors. Base on this logic, the sensitive cultural bacteria narrow pH range of neutral to alkaline has to be maintained; besides keeping them in a sufficiently moist and conducive warm environment; time of 1 to 2 days has to be set aside for it to work on. Controlling and maintaining these favorable conditions for the culture bacteria to stay alive seems a daunting task before we can see tangible results for severe problems; but may be feasible for mild situation. Thereafter the ammonia problem is to be further deal with by using an ammonia neutralizer as mentioned above, to complete the decontamination process. Leather rejuvenation follows with hydrating, first to remove suspended soiling within the leather structure follows with fatliquor replenishing to softening the leather with suppleness and strength when dry.
Leather Rejuvenator – Hydrating Conditioner
A leather safe hydrator has a pH range from 3 to 4, it is an acidic surfactantcy solution that is design to harmonize with the neutral pH of leather with a multipurpose functionality, such as:
• Hydrating dried, stiffed or shrunk leathers to separates the crushed, stick together fibrils and relaxes them in the inter-fibrillary leather structure for effective distribution of subsequent fatliquor.
• Facilitating colloidal water movement within the leather structure during the wicking process to move soiling particulates to the surface.
• Reactivating the dormant dyestuff to resurface thus reducing the contrast between the color coat and the leather crust.
• Reducing the interfacial tension as a preconditioner to eliminate blotchiness on subsequent application especially on absorbent leathers.
• Charging the leather protein fibers ionic positive below its iso-electric point to hydrogen bond with the ionic negative charged fatliquor.
• Checking surface cleanliness, since molecular layers of oil can prevent adhesion of subsequent coating.
• Facilitating better finish penetration during refinishing thus providing good surface properties, especially the uniformity of surface dyeing during aniline refinishing.
When use as a surface interfacial tension inspection purpose; a very light mist-spray suffices, to check for evenness of absorption to avoid blotchiness for subsequent application like fatliquor replenishing or dyestuff refinishing. When used as a leather structure rejuvenator, a complete plumping of the leather structure is highly recommended to realize its full potential. A check with thumb and finger with a little moisture oozing out would be the optimum level of hydration. When this level of moisture is reached, the damp leather is recommended to be sealed off with plastic cling wrapper to control evaporation. Dwelling while fully hydrated for up to 72 hours will deliver the result desired when the leather is further treated for optimum physical appearance.
Leather Rejuvenator – Fatliquor Conditioner
Fatliquor is a concoction of oil and related fatty substance derives from animal, vegetable and mineral sources; formulated as a stable emulsion that resembles the look of fresh milk in a bottle. The objective of fatliquor is for lubricating the leather fibrils like millions of interlocking miniature chains of hinges for flexibility and softness. Preconditioning the leather prior to accepting fatliquor topping-up has its share of contribution in many ways, in terms of appearance, without the blotchiness. The stiffness of leather if any, needs to be relaxed for an effectively distribution of the fatliquor. Leather fiber pH chemistry stability charge need be strengthen ionic positive (+ve), to hydrogen bond with the ionic negative (-ve) charge of the fatliquor. All these benefits from preconditioning the leather derive from the dwelling power of an acidic leather safe hydrator. It is a process of penetrating and distributing which lubricates the fibrils so that after drying they will be capable of sliding over one another smoothly. In addition to regulating its stretchability, compressibility and flexibility, the fatliquor contributes greatly to its rip tensile strength. Thus, helps to keep leather at its optimum physical performance and prevent premature ageing.
Leather Rejuvenator - Leather Scented Fatliquor Conditioner
As the name suggest, this is the leather-scented version, where the classical leather scent is infused into the fatliquor. Design for masking odor related problems or where leather scent is much sought after.