New posts (Nov 2011) on Autopia Detailing Wiki

Many of the following statements are controversial and are polar opposite of popular leather care practices recommended by product manufacturers. I've found that some leather care myths are deliberately perpetuated by the industry, especially those on the use of oil-based leather conditioners and others are just common errors of judgment.

Modern (> 1990) automotive finished leather upholstery used by 95% of OEM has multi- strata finish, the actual hide which must be kept hydrated to maintain tensile strength, elasticity and suppleness to prevent the hide from cracking and becoming dry. Within the top strata (urethane) which provides protection from abrasion and the surface coloring (pigmentation) which can wear off from normal use. This can be exacerbated by oils from the skin and grit, both of which act like an abrasive and can wear a hole in your bolsters and arm rests if you don't keep the surface clean. Finished leather s only requirement is to be kept clean and protected, urethane doesn’t require conditioning.

Avoid using any product that seals or renders finished leather water-proof, this includes most of the newer polymer or silica coating type products as they will not allow hydration (transpiration and evaporation of moisture)

Not all conditioners are alike; some are aqueous (water- based) as opposed to oil-based, some are an emulsion of oil and water. Some use a solvent as a carrier system and when applied to the leather surface, it appears to “soak in”.

a) Proteins, collagens and oils cannot permeate the leather and therefore remain on the surface; the same thing will apply to seating surfaces; the problem will be exasperated as the oil will attract dirt/grime to the surface. So the claims of strengthening and nourishing the leathers fibres are groundless as the oils cannot permeate the leather and therefore remain on the surface; the same thing will apply to seating surfaces; the problem will be exasperated as the oil will attract dirt/grime to the surface.

The finished leather used in automobiles is removed from a dead animal and then is subjected to a tanning process. Why would a deceased animal skin (hide) require proteins and collagens, these types of proteins are used to ensure a healthy and elastic dermis and to ensure the tendons remain supple in living tissue.

b) When leather tanners talk about conditioning leather they are referring to re-hydration; not the replenishment or replacement of the fat liquoring oils and waxes. The only 'conditioning' required for finished leather upholstery is hydration; oil-based products cannot permeate the finish leather (urethane pigmentation and / or covering) that is used in 95% plus of modern automobiles.

Modern leather needs to be kept hydrated with moisture to ensure the leather remains flexible and maintains its soft tactile feel. The oils cannot permeate the leather and therefore remain on the surface; the same thing will apply to seating surfaces; the problem will be exasperated as the oil will attract dirt/grime to the surface. This is done by regularly wiping the surface with a damp 100% cotton micro fibre towel and by using aqueous (water- based) leather care products. There is no reason to use oil-based leather care products to condition or feed leather hides

Aqueous (water- based) products are able to permeate deep into the hide, unlike oil, due to its larger particles, whereas water particles are smaller than both oil and the molecules of urethane, which enables aqueous (water- based) products to permeate and provide hydration, which is essential for suppleness recovery.


In summary, an aqueous micro emulsion is readily absorbed into the fibres and provides lasting and effective lubrication without migration, while re-hydration leaves leather feeling silky soft and pliable.


See also "Leather Conditioning" article - http://www.autopia.org/forum/guide-d...ml#post1454835