The purpose of the AHFA Leather Education

Booklet is to publish information that assists retail

leather customers in making informed buying

decisions, and that equips the retail sales

associate / marketing specialist with overall leather

knowledge and education in order to correctly sell

upholstered leather furniture.

Published December 2004

The raw skins of animals were first used by primitive man to protect their bodies from severe weather, cold winds and rain during the ice age some 500,000 years ago. It was not until centuries later that man began to stretch out the skins and dry them under the sun to keep them from rotting. Some of the fluids from the animals were rubbed into the pores of the skins to soften the hides and make them more comfortable against human skin. It was discovered much later that parts of some trees contained an acid-like substance called tannin (or tannic acid), which could convert raw hides and skins into what we know as leather.

The bark of oak trees was the main material used. Some countries did not have oak trees so vegetable tanning materials like sumach leaves and other plant leaves were used. If the raw material was extremely thick, hides were soaked in the tanning liquid for as long as two years.

Once the tanning process was discovered, people began using leather for such things as footwear, clothing, saddles, holsters, bags, bindings, buttons, and many other things.

During the time of the industrial revolution, innovation and travel brought huge new opportunities for the makers of leather. Horse drawn carriages, luggage, trunks, upholstery and fashion all became important consumers of leather.

Nearly a century later, furniture design in the 1950s required softer, more pliable leathers for seating. This was accomplished by incorporating chromium salts in the tanning process.

Today, the leather industry continues to improve its methods and processes through aggressive technology but with an additional emphasis on protecting our natural environment. Similarly, with very few exceptions, animal hides are a by-product of the meat industry; almost all leather producing animals in just about every country are reared for the food they provide, not for their hides.

Leather tanning has come a long way from its primitive beginning. Early leathers were made primarily from ordinary cowhides, calfskins, pigskins, deerskins, and goatskins. However, today’s fashion-driven furniture, apparel, and clothing industries incorporate many exotic skins such as alligator, crocodile, and lizard, as well.

In a world of man-made materials, natural, elegant leather continues to command interest and appeal. Nothing says quality, fashion and style like leather.

 This is achieved by cleaning, drying, and preserving the hide. (See below for a more detailed look at the tanning process.)

Curing – The leather hide is cured by immersion in a salt solution to protect it from deterioration and to preserve it for future use.

Soaking – The leather hide is soaked in water to remove the salt solution and re-hydrate the hide to its original flaccid condition.

De-hairing – The soaked hides are treated with a lime solution for the de-hairing process.   The lime solution not only removes the hair, but also fats and soluble proteins.

Tanning – Tanning involves drumming the hides in a mixture of chemicals. Two of the most common types of tanning include chromium tanning, which results in a wet blue appearance, and vegetable tanning.

Splitting – The average thickness of a cowhide is 5mm before splitting. The hides are split in a splitting machine which activates a fast running wirecutter. This operation divides the hide into two pieces: top grain leather and split leather. The top grain hides are then shaved on the  flesh side to create a uniform thickness. Standard top grain upholstery leather thickness can be 0.9mm-1.4mm. Split leathers are typically used on non-stress areas, such as outside backs and outside arms.

Sorting – The hides are then sorted or separated by differing levels of quality. This quality is based on the extent of natural markings which could include tick bites, brands, barbed wire scars, and/or stretch marks. This process is called selection. The highest quality of leather hides are normally termed “A” selection. “B” and “C” hides possess a higher number of natural markings, therefore reducing overall selection.

Dyeing – The leather hide is drum dyed. The dye concentration in the drum affects level of penetration into the hide, richness of shade, colorfastness to light, ease of dry cleaning, and resistance to rubbing. The dyed leather is then treated with fat-liquors for softness and strength.

Drying – After the dyeing process, the leather hide can retain 45-60% water. Most upholstery leather is tunnel dried where the temperature and humidity are controlled. After the leather is dried, it dries to a paler shade as the oils spread uniformly and the dyes penetrate deeply.

Finishing – The finishing of a leather hide involves both mechanical and chemical treatments.

The hide is first trimmed and conditioned with fat-liquors to obtain uniform moisture content. The hide is then softened with a massage machine and stretched. Some leathers are further processed by applying a top coat finish to the grain surface. The top coat adheres to the leather’s surface while increasing the resistance to abrasion, cracking, peeling, rubbing, light, and heat. A pigmented finish is sometimes applied which contains a variety of colorations, resins, lacquers, oils and/or waxes. Afterwards, the hide is milled in a dry drum to soften the leather. Note: leather can be finished a variety of ways depending on quality of hide, type of leather, and level of pigmentation.

Graining – The grain, similar to human fingerprints, is unique to

each individual hide. It is the hallmark of full grain leather hides

and can vary from hide to hide or even within one particular hide.

identification marks and are part of virtually every hide.

Stretch Marks – Stretch marks occur as a result of giving birth

and become a permanent marking on the cow.

Healed Scars – Scratch marks are the result of the cow’s unsheltered

life and evidence that the hide is indeed top grain. Hides with fewer

scratch marks are usually more expensive, but the marks do not affect

strength or durability. Typical healed scars include those caused by

insect/tick bites and barbed wire marks.

Insect/Tick Bites – Scars caused by the abundance of insect and/or

tick bites. Typically, these scars heal but leave visible markings.

Fat Wrinkles – Wrinkles occur naturally in the loose skin around

the neck and belly of all cows. The skin must be loose to allow the

needed flexibility for grazing and overall growth.

Backbone – Natural furrows appear along the backbone of all

hides due to the animal’s physiology.

 Leather – An “Economical Choice” – Most customers are unaware that leather provides an economical approach to buying upholstered furniture. There are many types and styles of leathers that range in price. This allows each customer to experience the pleasure of owning leather furniture by offering affordable yet varying price ranges for all pocketbooks.

Leather is a natural material.

Leather is a lot like our skin – porous.

Leather “breathes” by absorbing up to 15% of its own weight in humidity/water. It absorbs and releases moisture that never stays on the surface enabling it to adjust to our body temperature.

Leather has excellent temperature adaptation making it comfortable during the heat of the summer and cool of the winter.

Leather molds to a form, but will not stretch out of shape.

Leather conforms to your body shape and becomes more comfortable with use.

Only leather ages so that it becomes more supple throughout the years.

Each leather hide is unique – No one hide is exactly like another.

Leather comes with its own distinctive markings and characteristics making each purchase truly unique.

Leather has legendary tear strength making it one of the strongest upholstery materials known to man.

Leather’s strength and elasticity gives it high ripping resistance.

Leather is naturally flame resistant and will not readily burn or melt.

When properly maintained, leather is easy to clean. Like our skin, leather has tight as well as strong fibers that prevent the penetration of dust, lint, animal hairs, or cigarette smoke.

Leather is an ideal choice for those persons who are dust-sensitive or possess allergenic conditions.

Basic Leather Classifications

Crust leather that has received only aniline dyes for color, then dried, softened and milled.

No protective finish.

Shades may vary from hide to hide and within a single hide.

Requires a high degree of preventative maintenance.

Susceptible to surface scratches.

Absorbent

May have special effects such as, but not limited, to wax, oil, etc.

Crust leather that has received additional aniline dyes, pigmentation for

color consistency, and/or a protective top coat finish, then dried, softened and milled.

May be partially or fully corrected.

Requires a low degree of preventative maintenance.

Surface is more difficult to scratch. Least absorbent.

May have special effects, such as, but not limited to, hand antiquing, savauge, etc.

Crust leather that has received only aniline dyes for color, then dried, softened, sanded or buffed, and milled.

Surface has a visible nap.

Shades may vary from hide to hide and within a single hide.

Requires a high degree of preventative maintenance.

Susceptible to surface scratches. May have special effects, such as, but not limited, to wax, oil, etc.

Avoid placing your furniture in direct sunlight (under windows or skylights). All materials will fade over time when placed in direct sunlight. Some leathers are especially sensitive to sunlight.

Maintain at least two feet between your furniture and heating sources. Prolonged exposure to heat vents and radiators will cause your leather to dry out.

Like all items in your house, leather can accumulate dust. You can fully remove dust particles from the surface with a soft cloth, making it ideal for dust sensitive persons.

Certain types of leathers perform better when preventative maintenance is practiced.

Your retailer may offer additional Leather Care and Maintenance suggestions or products.

Use of general household cleaning products, chemicals and abrasives are not recommended as they can break down the leather’s protective surface and cause damage. Never use harsh chemicals or cleaning agents (such as furniture polish, ammonia, or detergent soaps) on your leather furniture. Avoid all products containing solvents, silicones, or oils, as they may negatively affect the leather’s surface.

Techniques used to create this effect include tumbling the hides with abrasive items in order to scratch the leather’s surface.

This effect can be created during the finishing process either with a roller or spray equipment, or by hand. Similar to faux finishes on walls.

Natural markings may be visible with semi-aniline leathers.

Grain. The Top Grain of the hide is stronger and more flexible.

Wet Blue – Refers to the “blue” color and appearance created by the chromium tanning process.

The contents of this booklet have been compiled from the contributions

of leather suppliers, leather upholstery manufacturers, furniture retailers, and industry consultants.

All materials submitted have been carefully edited and placed in a

format designed to establish “standards” that can easily be recognized

by all segments of the leather industry. Acceptance and practice of the enclosed information is entirely at the discretion of the reader.

The American Home Furnishings Alliance (AHFA) has supported and

approved the development and publishing of this collection of industry