The Science of Leather: Why Proper Conditioning in Important
I get asked a lot about oiling or conditioning a baseball glove. This blog entry dives deep into the science with a clear and concise description about what’s going on inside the leather and what characteristics a good glove oil or glove conditioner should have.
The Living Material: Understanding the Microscopic Failure of Leather
Leather is not merely a fabric; it is a preserved biological wonder. It starts out as skin - a living bodily organ that can heal itself with scar tissue. Once the hide is harvested (the cow is dead) it loses that self-healing resiliency and begins to deteriorate. The tanning process halts the degradation, preserving the skin as leather. Unlike synthetic textiles woven from uniform strands, leather consists of a complex, chaotic network of millions of microscopic collagen fibers. When healthy, these fibers slide effortlessly past one another, giving high-quality leather its legendary flexibility and strength.
However, the cracking you see on an old glove, or even a leather jacket or sofa is not simply a sign of "old age"—it is a visible symptom of a specific chemical and physical failure occurring deep within that fiber network. As leather ages, the essential fats and liquors introduced during the tanning process degrade or evaporate due to environmental conditions like low humidity and UV exposure.
Without this internal lubrication, the collagen fibers no longer glide; they grind. This microscopic friction eventually snaps the fiber bonds, leading to the irreversible internal damage. Eventually the damage deep inside works it’s way up to the epidermal (outside) layer. We recognize this as cracking. To prevent this degradation, we must first understand the science of what keeps this "living" material alive.
The Role of pH Balance: The Invisible Destroyer
To understand why generic cleaners are fatal to leather, you must understand chemistry. Leather is inherently acidic, with a pH balance typically stabilized between 4.5 and 5.0 during the tanning process. This acidity is critical; it preserves the chemical bonds that hold the collagen fiber network together.
The danger arises when unsuspecting owners use standard household cleaners—dish soap, window cleaner, or laundry detergents. These products are almost exclusively alkaline (High pH). When a high-pH alkaline solution is applied to low-pH acidic leather, a damaging chemical reaction occurs instantly.
This reaction attacks the hydrogen bonds within the collagen bundles, effectively "un-tanning" the hide. It doesn't just dry the surface; it destroys the structural integrity of the material. With repeated exposure, the fiber bundles lose their cohesion, causing the leather to become brittle, weak, and eventually rot from the inside out. Once this chemical structure is compromised, the damage is irreversible.
Prevention: The Science of Conditioning
To prevent the microscopic friction that leads to cracking, we must mimic the original tanning process through a technique known as "re-liquoring." This involves replenishing the essential oils (fat liquors) that have evaporated over time, restoring the internal lubrication that allows collagen fibers to slide effortlessly past one another. This is exactly what Advanced Leather Conditioners do.
However, effective conditioning is about more than just adding moisture; it is a matter of pH balance. Just as alkaline cleaners destroy the fiber network, an improperly balanced conditioner can destabilize the leather's structure. You must use a conditioner chemically formulated to match leather’s natural acidity (pH 4.5–5.0). This lubrication is absorbed deeply into the internal fibrous structure, protecting the hide without disrupting its chemical integrity.
By routinely introducing these pH-balanced lubricants, you maintain the leather's resilience. A conditioned fiber is a flexible fiber; it bends under stress rather than snapping, keeping your leather soft, supple, and crack-free for decades.
If you have any questions about this chemical engineering stuff, I’m happy to answer them. Drop me a line on my email: Kevin@ADVLeather.com.
