Leather Types & Characteristics

Leather and suede are both products derived from the skin of hides of animals. Skin refer to small animals whereas hides refer to larger animals from which the leather is taken. These may include domestic animals such as cattle, goats or sheep; or wild animals such as kangaroo, deer, alligator, buffalo or seal. Suede is produced from lower portion after splitting the hide into two halves, or reversing the skins or hides. It is then mechanically abraded on the surface to create a soft nap. Calfskin is younger, therefore finer and softer than cowhide.

Production of leather begins with removal of the skin from animals flesh. Initially there is removal of hair and fibre, but this is not allays the case. Sometimes the hair, fibre or wool is left on to create a ‘double face’ leather. This type of leather with its surface hair is used for pilot seats, area rugs, etc. The skins and hides are then subjected to the “wet end” which will convert the animal hide to leather through a process called “tanning”. Initially there is removal of hair and fibre. Tanning is used o remove the water remaining in the skin, and to prevent the skins and hides from deterioration and decay. Tanning also makes leather softer and more flexible. Mineral tanning agents include aluminium sulphate and chromium sulphate (chrome tanned). Vegetable tanning agents include oak bark, hemlock bark, sumac and palmetto, and cod liver oil.

The leather hides are often split into different thickness depending on their intended use. The tanned leather is then finished using steel rollers or flat plates. This process is capable of imparting specific textures and patterns to the leather. Some inferior leather or second grade hides can be changed into more serviceable or made to look like higher grade leather.

Here is a very brief description of the steps that are used. Each of these steps is important and reacts with the follow steps.

Curing
When the animal is slaughtered it is immediately subject to decay. In order to stop bacterial damage the hide is subjected to various operations to put it into static sate. The most common method involve the use of salt as an agent to stop any microbial growth. One method involves using salt in the same weight as the hide and applying this to the flesh side. The leather is then stacked and can be stored for a period of time before processing.

The next method is similar but involves the use of a raceway curing system where the hides are placed in a pool in the shape of a raceway that is filled with water that has been saturated with salt. Paddles move the hides around the raceway ensuring adequate uptake of the salt solution. Once the hides are saturated they can be stored up to six months before further processing. Other Methods include air drying and freezing.

Soaking
Hides are soaked in water that contains agents designed to facilitate wetting. After soaking, the hides are washed to remove the excess salt and other contaminants.

Liming
High pH (calcium hydroxide, sodium sulphate) chemicals are used to weaken and remove hair.

Splitting
The hide is divided or split to ensure even thickness of the top grain. The bottom portion is referred to as the split. The top portion is the grain and may also be full grain.

Bating
Bating removes the chemicals used in the liming process. This is accomplished with neutralising agents and enzymes.

Pickling
This steps controls the pH of the leather, adjusting it for optimum results in the tanning process. Chrome tanning will not perform well in alkaline conditions. Dilute sulphuric acid is used, buffered with salt to prevent swelling of the hide.

Tanning
This is the actual transformation of the decaying material into an inert fabric. Chrome salts are the tanning chemical of choice for its speed and for the physical attributes it contributes to the leather. Vegetable tanning us used for heavier leather that is suitable for the shoe, equestrian or belting markets. Combination tanning processes are also common.

Wringing
This is a mechanical step to remove excess water.

Shaving
This ensures an uniform thickness of the hide. Variations up to 10% in thickness can occur, even on the same hide.

Re-tanning, Dyeing, Fat Liquoring
Considered as one step, the hides are re-tanned to give unique characteristics (white, or very soft leather). The leather is then dyed with basic or acid dyes to give the desired colour. Fat liquoring is the addition of oils to replace oils lost in the tanning process and will contribute to its handle or feel.

Drying
The leather is dried in rooms that allow moisture evaporation through the ventilation of the air. Vacuum drying is an alternate method used. The hides are dried under strict control of humidity and temperature to ensure it maintains the proper feel.

Buffing
Some hides are buffed to remove minor imperfections in the hide and to give a surface that will readily accept the dolour or pigment coats.

Finishing (broad type definition):
Finished leather is any leather that has a film on the surface. The film is composed of a binder and pigment and can be as thing as human hair. The finish will develop micro cracks with use that are visible to the human eye. These hairline fractures will allow access of the cleaner into fibres of the leather.

Aniline leathers
Aniline leathers are dyed only, therefore porous and do not have any protective coating on the surface. This porous leather will allow immediate penetration of any liquid or cleaner into the fibres. If left untreated, they will show the history of their use in the ‘patina’ that they will develop. If materials spilled on the surface have any dyeing characteristics, the fibres will be stained or discoloured. Cleaning will not remove the majority of these stains. One answer to this problem is to treat the leather with a chemical to provide a ‘barrier coating’ similar to scotch-guard or Teflon fluro-chemicals protectors. This will act as a repellent and give you time to remove the soil by keeping suspended above the fibres.

Aniline (A) or porous leathers
Use a fingernail, bone spatula or equivalent to lightly scratch or roughen  the leather surface. If the scratched areas turns to a lighter colour and the leather is plain surfaced (no pile), then it’s likely an aniline type. Alternately you can rub a wet surface, such as wet bone spatula or wet your finger, into the leather. If it darkens somewhat, and then dies back to the original colour, again it’s probably aniline type. Other aniline leathers may be known as unprotected, naked or raw; or even crust.

Protected (P) or non porous leathers
use a fingernail , bone spatula or equivalent to lightly scratch or roughen the leather surface. But unlike aniline leather, it the scratched area does not change colour or lighten, then it is finished or protected leather. Alternately you can apply a leather cleaner or conditioner in an out of the way location. The leather care product should no markedly alter or change colour to the leather. An aqueous (water) based cleaner will usually bead up on the shiny leather surface (if any protection is remaining) of a protected leather.

Nubuck (N) leathers
This type of leather will have a soft, very low and uniform pile or softly “micro-sanded” surface. It can appear similar to a microfiber textile fabric, very low pile velvet, or even to some aniline leather. Also if you wet the surface slightly, nubuck will darken noticeably. It may dry back to the original shade or slightly darker, depending on how the nubuck leather was finished. Nubuck are generally porous leather, but can be finished with a fluoro-chemical to provide some resistance to water penetration and staining.

Your Aniline leather furniture will also be known as NaturalUnprotectedNaked, or Pure Leather.

  • Keep your furniture at a distance of minimum two feet from any heat source. Exposure to heat radiators or vents for a prolonged period of time dries out your leather.
  • Do not place your furniture where direct sunlight falls. This is because all materials tend to fade over time if placed under direct sunlight, especially Aniline leathers which are extremely sensitive to sunlight. Avoid placing Aniline leathers under skylights or in windows.
  • Like any other item in your house, accumulation of dust can happen on leather as well. On a weekly basisuse Leather Master Soft Cleaner on a lightly dampened soft cloth to remove the dust. On your vacuum cleaner, you can also use a soft brush attachment in order to completely remove the dust particles from the surface of Aniline leather and make it suitable for people who are sensitive to dust.
  • All types of leathers last longer if you do preventative maintenance on a regular basis. Application of Leather Master Protection Cream on the surface of aniline leathers helps you to keep it clean, resist staining and prevent soiling in general. However, you must pay specific attention to protect areas like arms, seats and backs that are put to heavy use.
  • As a routine procedure, clean your furniture thoroughly with Leather Master Soft Cleaner once in every six months so as to remove dirt and any gradual perspiration and body oils accumulation. Further, more frequent cleaning of Aniline leathers may be required if you place the furniture upholstered with this leather in areas such as a TV room where they are subjected to heavy use. It is also important to apply the Protection Cream once again to Aniline leather after cleaning to enhance the protection level.
  • To keep your leather looking its best, do not place it in direct sunlight. This can result in fading over time.
  • In fact, it is also best to keep all leather furniture a minimum of two feet away from a heat source, like radiators and vents, as excessive exposure to heat can also cause fading and make the leather dry out and crack easily.
  • Clean leather furniture regularly with a soft damp cloth. However, never use abrasive or harsh cleaners as these can cause permanent damage to leather surface. Also, it is not recommended to use any kind of furniture polish, wax or oils to clean leather furniture. Instead, use products like Leather Master Soft Cleaner to maintain your furniture. The use of such a professional grade product once every three to six months will gently remove any dust and dirt along with body oils from the surface, without causing any adverse affects.
  • Make sure you clean spills immediately as leather is highly porous and it can be very tough to remove old stains later without ruining the leather.
  • For a good maintenance plan to keep your leather furniture looking fresh and new, use professional grade products like Leather Master Protection Cream. This product will prevent soiling and resist staining, hence making it a lot easier to clean your furniture regularly.
  • Keep your leather items away from direct sunlight. Sunlight tends to hasten the fading of nubuck leather, so be sure to distance your furniture from windows, skylights or glass doors.
  • As much as possible, keep your leather furniture at least two feet away from heat sources such as radiators or vents. Sustained exposure to heat causes the leather to dry out.
  • Vacuum at least once a week to keep the leather free from dust.
  • Wipe off any surface dirt using the Leather Master Nubuck Cleaning Cloth. Simply fold a soft, dry sponge into the cleaning cloth, and then rub the leather in various directions. This will lift off any dirt and soiling on the surface of the leather. The buffing action will also restore the velvety texture, reviving areas that have become smooth and flat from wear.
  • All leather products can benefit from preventive maintenance. Apply the Leather Master Nubuck Protector to make it more resistant to dirt and stains. Pay special attention to areas that are most prone to friction, such as arm rests, back rests and seats.
  • Treat water-based stains with the Leather Master Nubuck Cleaner. Squeeze a small amount onto a soft sponge, and then apply the foamy substance onto the affected area. Rub the material to remove the stain. For oil-based stains, use the Leather Master Degreaser. After drying, buff the surface with the Nubuck Cleaning Cloth to restore the leather to its original texture. Finish off with the Nubuck Protector to prevent soiling and staining.

Tips for Avoiding Leather Furniture Sun Damage

Sun and leather furniture are not friends. They do not usually mix well. Exposure to too much sunlight may lead to fading and drying. While leather wear and tear can’t be avoided, sun damage can definitely be prevented.

Fading

Fading is usually seen in semi-aniline and aniline leathers. This is a common problem with these types of leather furniture, particularly when your furniture is placed next to a window that gets considerable amount of sunlight. In just four to six months, you can see fading in semi-aniline and aniline leather furniture if you put expose them to sunlight.

Drying

Sun can cause drying to almost any type of leather. Whether your leather furniture is fully finished or not, sunlight can cause drying because it can slowly evaporate natural oils in the leather. When the leather gets dry, it will stiffen and crack.

Fading and drying are two common problems caused by exposure to sunlight. This does not mean, however, that you have to live in darkness 24/7. It just takes preventive ways to avoid sun damage. Here are the simple things you can do to avoid leather sun damage.

Keep your leather furniture shaded

This is the surest way to protect your leather furniture from sun damage. Place your furniture out of direct sunlight to avoid drying and cracking. This is especially true if you have semi-aniline and aniline type leather furniture. If you cannot move your furniture to a shaded part of your home, at least close blinds to not allow sunlight come in during the hottest and sunniest time of the day.

You should not use dark colours to cover your leather furniture because dark colours absorb more light. You can also apply commercial tinting film to your windows to block ultraviolet rays. UV rays cause the most damage to leather.

Keep your furniture from heat source

You should move your furniture away from heat sources like furnace or fireplace. Long term exposure to heat sources can also lead to drying and cracking.

Clean and protect your leather

Regular cleaning and conditioning help your leather furniture prevent sun damage. Having it cleaned by a professional leather cleaning company like McArdles Cleaning Services can make sure that your leather is thoroughly cleaned and protected.

Our professional leather cleaners can make your furniture looks both elegant and beautiful. Whether you have protected leather (aniline, semi-aniline, pigmented, and finished leather) or any other type, we can clean and protect it. Our leather protection products are the best in the industry. We use water-based leather protection cream to extend the life of your furniture.