What is Unfinished leather

Unfinished leather

Section through automobile leather upholstery

Be cognizant that you’re dealing with the finished coating on the leather and not with the leather hide itself

Research

Information regarding the care of leather is scarce, often contradictory, misleading, or simply wrong. Misinformation can lead to inadvertent damage to your vehicles leather upholstery; my goal is to present clear, concise, accurate information.

There is a great deal of conflicting information on leather care being put out by leather experts themselves who use baffling pseudo scientific techno speak as another marketing ploy, which makes it difficult to find a definitive, unbiased answer. It had always confounded me that such a simple subject has been made into something so complicated.

Many vendors and indeed, some older generation detailer’s advocate the use of products and methodologies that are more suitable for a by-gone era of leather surface finishes as opposed to the pigmented urathane coatings used in modern vehicle upholstery


After various meetings and discussions with leather tanners, fat liquoring formulators, their chemists and many leather care product manufacturers I’ve gained an understanding of this versatile material on both a practical and scientific level.

I have always thought that the more facts and information you have at hand the easier it is to judge what information you are being given. After all, how can you fully understand and properly use any product unless you have all the facts? In the final analysis; it’s your vehicle, your hard earned money and your choice

Unfinished vs. Finished leather

a) Unfinished leather - the appeal of this type of aniline leather is its initial "natural" look and the soft, supple texture. The downside is aesthetic vulnerability; due to the porous nature of untreated leather, it stains easily and it is sensitive to ultra violet (UV) light, which means that the colour is subject to photochemical degradation (bleaching, (fading), discoloration, chalking, brittleness and cracking) all indications of UV deterioration. The porous nature of unfinished leather will allow a water- or oil-based solution to permeate the leather.

One of the best known tanneries supplying this type of leather hide was the Connolly Leather Company, London; they supplied leather hides to many British luxury car manufacturers like Aston Martin, Bentley, Ferrari, Jaguar, Lotus, and Rolls Royce. This English tannery had been producing and supplying highly finished, vat dyed leather primarily to car manufacturers at two plants, Northampton and Ashford, Kent. The term is also used to describe the particular brand of leather itself, when fitted in a car interior, as an expression of the quality and luxury status of the vehicle. Only the highest quality top grain (the top 0.05 inches of the hide) was selected for their use, this grade of leather is now only used in less than 5% of automobiles).

b) Finished or micro pigmented leather - is commonly used for automobile as these resins create a film that protects the leather. The water-based urethane pigmented (colour) coat and the clear topcoat provides abrasion and stain resistance.

This type of leather finish is the most durable and easiest to care for but tends to be stiffer than both unfinished and micro pigmented leather. When Ford first introduced its King Ranch leather in their F-Series trucks it had unfinished leather, later they adopted a micro pigment type finish

Using advanced micro pigments this finishing technique makes the finish rigorous enough to stand up to the conditions it would be subjected to in an automobile. Generally speaking micro pigment style leathers come in very earthy natural colours, incorporating a small quantity of pigment (a thin clear sealant that provides a uniform colour and affords some protection) but not so much as to conceal the natural characteristics of the hide so it will still retain the soft hand of Aniline leather. This type of leather is also used for perforated leather finishes.

Top-grain premium Aniline leather is mostly used in prestige European automobiles; Aston Martin, Bentley, Ferrari, Jaguar, Lotus, and Rolls Royce, US Cadillac and high-end German automobiles such as; Audi, BMW, Daimler AG, Mercedes-Benz, and Porsche, for some of these vehicles premium leather is standard OEM specified equipment, but for most it’s a ‘premium’ package that costs upwards of 2,000 USD . This is the niche market sector both Leatherique and Connolly were originally formulated for.

Be cognizant that most if not all OEM leather in these vehicles is now a semi-aniline (micro pigmented) finished leather Is a term used by the auto leather industry to better describe leather with a thin urethane layer of pigment coating, which provides an even colour and both abrasion and stain resistance. As opposed to the mislabelled Aniline leather (aniline is a dye (immersion) method not a leather type), which will absorb body oils and moisture and would be subject to abrasion unless it has been treated in some way.

Modern Leather Surface Technology

Automotive leather surface coatings have undergone major technological improvements over the past few decades. The leather used for automotive upholstery is finished leather; the ‘finish’ applied to the leather hide is a pigmented (colour) urethane protective layer and a clear abrasion resistant topcoat.

This type of leather has an aqueous (water- based) urethane pigmented (coloured) coating, think of it as a urethane paint applied on top of the leather, and then a clear top coat is applied, o you are not actually touching the leather.

The coating gives the leather more durability and protection. It is also much easier to clean. Finished leathers make up almost all auto leathers. Just because leather has a top coat doesn't mean it is any less desirable.

It also has micro-pores that allow transpiration, i.e. evaporation and hydration (the passage of water vapour through a membrane or pore) they are not sealed per se

Micro pigmented finished leather in more often used for automotive upholstery as it is more durable than uncoated aniline, whilst still retaining a natural appearance Semi-Aniline (micro pigmented) finished leather coating containing a small amount of pigment in the base coat, this surface coating helps impart greater stain resistance.

The increased durability is provided by the application of a light surface coating which retains the ‘feel’ of soft leather and contains both pigment (colour) and an anti-abrasion additive, this ensures consistent colour, imparts stain resistance and helps with the abrasion of entering and exiting the vehicle

Pigmented leather won't absorb liquids because of the protective properties of the finish making for easier clean-up. Since the leather hide has a clear coat finish, when treating the leather, so you are in fact dealing with a urethane (to all intents and purposes; that simply needs to be kept clean and hydrated…it really is that simple.

A simple concept that been stated a million times and still some will swear that treating finished leather with a conditioner is beneficial. But if you feel $50 plus and approx 2-3 hours work is a worthwhile investment of time / money to treat a urethane pigmented covering, that’s your choice

Surface care and preservation

The preservation of leather is a relatively simple matter. Keeping it clean and supple require no special abilities. Periodic hydration and cleaning with a water-based cleaner will remove most abrasive surface dirt and regular applications of a beneficial softener to ensure the finished leather remains soft and supple; Leather Master™ Soft Touch (ex Vital) - this is not a conditioner per se; it contains polymers in an aqueous emulsion and is used to improve and maintain the tactile feel and lustre by rehydration.

Protect the surface finish (Leather Master™ - Protection Cream) as a sacrificial layer; this way you are not actually cleaning the Leather's original surface, but cleaning from the surface of the protection. It also makes dirt easier to clean off

With leather, it is much easier to practice prevention than it is to try to resolve major challenges after the fact. Leather Protection will also work to remove small surface scratches on finished leathers. In general, Leather Protection Cream is used as a final step in combination with most of the Leather Master products.

Leather Master™ - Protection Cream (a Scotchgard™ type product specifically formulated for lather) the polymers penetrate the surface of finished leather and cross-link to form a durable protective film that is breathable, allowing transpiration and keeps the leather supple.

Being aqueous (water- based) it restores moisture to finished leather and provides a protective sacrificial barrier against all kinds of soiling, water, oil, alcohol-based stains and perspiration marks, so you are cleaning the protective layer

I hope you’ve found this article both informative and helpful.

TOGWT® Autopia Detailing Wiki Articles

1. “What exactly is ‘Finished leather’? “ - http://www.autopia.org/forum/autopia-detailing-wiki/145364-what-exactly-%91finished-leather%92.html

2. “Aniline Leather (Micro pigment) Cleaning and Care” – http://www.autopia.org/forum/autopia-detailing-wiki/137167-aniline-leather%3B-cleaning-care.html#post1455011 [/url]

3. “Proper Finished Leather Cleaning and Care” - http://www.autopia.org/forum/guide-detailing/136421-proper-finished-leather-cleaning-care.html

4. “Leather Upholstery Type Surface Identification” - http://www.autopia.org/forum/autopia-detailing-wiki/136895-leather-upholstery;-surface-identification.html#

5. “Leather Articles Hyperlinks” -http://www.autopia.org/forum/autopia-detailing-wiki/141973-leather-articles-hyperlinks.html