Product Overview
Urine becomes an alkaline toxicity when fermented by the natural bacteria from the atmosphere, causing its pH value to rise.
The pH value of leather is neutral at 3-5; any noticeable ammonia odor indicates that the pH has risen to 10.
Reaching an alkaline toxic level, the leather constituents like the tanning agent, dyestuff, and fatliquor migrate, leaving behind discoloration and rings from dyestuff, tackiness from the tanning agent reverting to rawhide, whitish spew from fatliquor stiffen and dry out the leather.
Nubuck is a top-grain cattle leather that has been buffed on the grain side to create a luxurious velvet-like nap. Known for its exceptionally soft feel, nubuck is often mistaken for suede but differs in strength and structure: nubuck comes from the grain side, while suede is from the flesh side.
Though aniline dyed through, nubuck is frequently finished with a light surface dye—sometimes with micro-pigment—to mask natural blemishes. It is both hydrophilic and oleophilic, meaning it readily absorbs water and oils, which makes it highly sensitive to stains and fading.
Over time, sun exposure can fade the surface, but the dormant dyes within can be reactivated through hydration, similar to steeping tea leaves. For this, Hydrator 3.3 is used to revive the color and prepare the leather for conditioning.
Follow with Fatliquor 5.0 to restore lost oils and fat, which enhances color intensity, restores suppleness, and reduces water and grease ingress. Fatliquoring also helps maintain plumpness and flexibility, preventing creasing and stiffness.
Nubuck is an amphoteric material, meaning it is pH-sensitive and reacts to chemicals. Therefore, always use a leather-safe care system within pH 3 to 5 to preserve its chemistry and ensure long-lasting beauty.
Urine is a biological compound waste made up of urochrome (coloring agent), uric acid, and ammonium salts. When urine is deposited on Nubuck, it attracts airborne bacteria, which ferment the protein component—resulting in a putrid odor, while the ammonium salts convert into ammonia, producing a strong alkaline smell.
Once the ammonia odor becomes noticeable, the pH level of the contaminated Nubuck can reach as high as 10—well above the leather-safe range of pH 3 to 5.
Nubuck is an amphoteric protein material, meaning it can shift its ionic charge based on pH. At high alkalinity (pH 10), the protein fibers become negatively charged, repelling other essential components like tanning agents, fatliquor, and dyestuff—similar to how like poles of a magnet repel. This disruption of the Nubuck’s internal chemistry leads to a breakdown of hydrogen bonds, causing the leather to denature and begin reverting to rawhide.
Urine-contaminated Nubuck requires immediate and specialized decontamination to reverse the high pH damage and restore leather chemistry. Nubuck-safe Urine Decontamination Systems use:
Leather Urine Cleaner 1.5Urine 1.5 by Leather Doctor is a pH 1.5 balanced specialty urine cleaner and neutralizer from reverting the Nubuck leather into a sticky rawhide.
It is a water-based urine pre-cleaner working in conjunction with Urine Odor Killer 2.1 depending on the severity of the urine contamination. When contamination is odorous and discolored, proceeding with Urine 2.1 is mandatory to achieve the desired result. However, displaced original fat and oil will need to be replenished for suppleness with potential refinishing.
Acidifier 2.0 by Leather Doctor® is a pH 2.0 Nubuck-Safe™ solution specially formulated to restore nubuck leather affected by alkaline cleaners or household spills.
This pH 2.0 acidifier helps correct issues like tackiness, dye bleeding, and stiffness by rebalancing the leather’s pH and reinforcing its internal structure.
By strengthening the ionic bond between negatively charged tanning agents, dyestuffs, and fatliquors with the positively charged nubuck protein fibers, this treatment brings leather back to a healthy, squeaky-clean condition.
Key Benefits:
With its pH-balanced formula (4.5), it effectively cleans delicate materials without causing common problems like ring marks, browning, or texture damage. Whether you’re cleaning high-end accessories, shoes, or upholstery, this cleaner is an ideal choice for maintaining your items’ integrity and appearance.
Its ionic positive (+ve) charge strengthens the bonding between the negatively (-ve) charged leather constituents—such as tanning agents, dyes, and fatliquor—reducing common issues like tackiness, dye bleeding, and stiffness caused by pH imbalance.
This Acidic pH 3.0 Rinse & Balancer for Nubuck Leather enhances the overall integrity of nubuck leather by lifting and removing suspended soiling through towel extraction, helping maintain its softness, color stability, and natural nap.
Urine 2.1 is a professional-grade, leather-safe decontamination solution that neutralizes urine odors, and prevents leather damage caused by urine exposure.
Its primary function is to relax and restore leather structure by reducing stiffness, softening creases, and minimizing wrinkles. This treatment promotes colloidal water movement within the leather fiber structure, helping to reactivate dormant dyes and bring them to the surface, resulting in a richer, more even coloration. Used as a preparatory step before fatliquoring, it sets the stage for deeper conditioning and long-lasting suppleness. For best results, follow up with Fatliquor 5.0.
Fat liquor is the life-blood of Nubuck! When fat liquor diminishes through aging, dry rotting set in and the Nubuck loose it tensile tear strength and easily rip.
Fat liquor breaks the hydrogen bond when exposed to alkaline toxicity and the Nubuck dried out stiff and shrunk.
Alkaline toxicity is restored with Restorer 1.6 followed by neutralizing and protonating with Acidifier 2.0 to increase the Nubuck ionic positive (+ve) charge with the fat liquor.
Hydrator 3.3 is the pre-conditioner that relaxed the stiff Nubuck fiber preparing for an effective fat liquoring.
Conditioner S Plus is a specially formulated conditioner designed for Nubuck leather.
Urine contamination on nubuck requires a biochemical and pH-sensitive approach. This process focuses on neutralizing the high alkalinity, restoring the amphoteric leather structure, and fully reconditioning the nap.
⚠️ Important: Always test products in an inconspicuous area. Work in a well-ventilated space. Use Nubuck-safe tools (Nubuck brush, Nubuck Eraser, absorbent towels).
✅ Step 1: Remove Surface Contaminants
- Product: Urine 1.5
- Purpose: Breaks down and emulsifies urine residue on contact.
- Procedure:
- Shake well and apply Urine 1.5 to the contaminated area using a Nubuck brush and/or Eraser 4.
- Gently agitate with a Nubuck brush in circular motions to break up surface soiling.
- Blot with a clean, absorbent, white towel.
✅ Step 2: Acidify and Rinse
- Product: Acidifier 2.0
- Purpose: Lowers pH, neutralizes alkalinity, and returns protein fibers to an ionic positive (+ve) state.
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Procedure:
- Apply Acidifier 2.0 evenly.
- Let dwell 3–30 minutes.
- Gently brush to remove residues.
- Blot out moisture with absorbent towels.
✅ Step 3: Neutralize Ammonium Salt
- Product: Urine 2.1
- Purpose: Targets and neutralizes ammonium salts to prevent off-gassing ammonia odor.
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Procedure:
- Apply and brush Urine 2.1 thoroughly.
- Allow 15–60 minutes dwell time for biochemical neutralization.
- Blot off with white towel. Repeat if odor persists.
✅ Step 4: Hydrate and Purge Contaminants
- Product: Hydrator 3.3
- Purpose: Ionic recharging, inter-fibrillary movement of contaminants, and prep for wicking urochrome.
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Procedure:
- Apply Hydrator 3.3 generously to saturate the affected area.
- Use cling film to cover and dwell for up to 4–8 hours (or overnight for aged contamination).
- Remove cling film and place clean white wettable paper towel as an extension of the leather.
- Allow natural drying—yellow urochrome will wick into the tissue, drawing contamination to the surface.
✅ Step 5: Inspect for Residual Staining
- If yellowing or odor remains, repeat Hydrator 3.3 with tissue wicking until fully clear.
- Only proceed once the contamination is fully removed.
✅ Step 6: Recondition with Fatliquor
- Product: Fatliquor 5.0 Plus
- Purpose: Replenishes fat and oil lost during contamination, restores suppleness and strength.
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Procedure:
- Shake well and apply Fatliquor 5.0 Plus while the leather is still damp.
- Apply in multiple light coats with 30-minute intervals between applications.
- Let leather absorb as much as it can (target 14% moisture regain of leather weight).
- Allow to dry naturally, then gently massage or stake the leather to soften the nap.
✅ Tips Beyond the Stain Spot
- Product: Nubuck 4.5, Rinse 3.0, Hydrator 3.3 and Fatliquor 5.0
- Purpose: Cleaning, rinsing, hydrating and fatliquoring beyond the urine stain to the rest to even out appearance and suppleness.
- Procedure:
- Shake well, apply Nubuck 4.5 to the stain spot, and extend to the remaining surface without a dry edge using a Nubuck brush in a circular motion. This will ensure an even wet-out appearance.
- Blot with a clean, absorbent, white towel.
- Rinsing with Rinse 3.0 as above procedure.
- Hydrating with Hydrator 3.3 follows after Rinse 3.0 as above procedure.
- Fatliquoring with Fatliquor 5.0 Plus while the leather is still damp.
✅ Tips Inspection for Dye Damages
- Product: Aniline Staining Dye 21, Leather Pigment 54 and Suede Dye Fix 99
- Purpose: Color repairs is match up with Dye 21 and Pigment 54 and Fix with Fix 99 accordingly.
- Procedure:
- Color repair if necessary is repaired before conditioning finishing with Conditioner S Plus.
✅ Optional Finish Touch-Up
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Once dry, rejuvenate the nap with a nubuck brush.
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Apply Nubuck Conditioner S Plus if desired for added smoothness, softness and leather scent.
Urine decontamination is not just cleaning—it is a biochemical restoration. The process neutralizes harmful high pH, purges deep contamination, and restores the internal structure of the Nubuck with fat and oil. This holistic system helps maintain the supple strength, resilience, and luxurious nap nubuck is known for.
Edited September 18, 2024 | May 13 2025 by Roger Koh.