Leather types
In general, leather is sold in three forms (sources wikipedia) :
- Full-Grain leather, made from the finest raw material, are
clean natural hides which have not been sanded to remove
imperfections. Only the hair has been removed. The grain remains in
its natural state which will allow the best fiber strength, resulting
in greater durability. The natural grain also has natural
breathability, resulting in greater comfort for clothing. The natural Full-Grain
surface will wear better than other leather. Rather than wearing out,
it will develop a natural "Patina" and grow more beautiful
over time. The finest leather furniture and footwear are made from
Full-Grain leather. Full grain leathers can mainly be bought as two
finish types: aniline and semi-aniline.
- Corrected-Grain leather, also known as Top-Grain
leather, is fuzzy on one side and smooth on the other. The smooth side
is the side where the hair and natural grain used to be. The hides,
which are made from inferior quality raw materials, have all of the
natural grain sanded off and an artificial grain applied. Top grain
leather generally must be heavily painted to cover up the sanding and
stamping operation. Corrected grain leathers can mainly be bought as
two finish types: semi-aniline and pigmented.
- Suede is leather that has had the grain completely removed or
is an interior split of the hide/skin. During the splitting operation
the grain and drop split are separated. The drop split can be further
split (thickness allowing) into a middle split or a flesh split. In
very thick hides the middle split can be separated into multiple
layers until the thickness prevents further splitting. The strongest
suedes are usually made from grain splits (that have the grain
completely removed) or from the flesh split that has been shaved to
the correct thickness. Suede is "fuzzy" on both sides. Suede
is less durable than top-grain. Suede is cheaper because many pieces
of suede can be split from a single thickness of hide, whereas only
one piece of top-grain can be made. However, manufacturers use a
variety of techniques to make suede appear to be full-grain. For
example, in one operation, glue is mixed with one side of the suede,
which is then pressed through rollers; these flatten and even out one
side of the material, giving it the smooth appearance of full-grain. Latigo
is one of the trade names for this product. A reversed suede is a
grained leather that has been designed into the leather article with
the grain facing away from the visible surface. It is not a true form
of suede.
Other less-common leathers include:
- Buckskin or brained leather is a tanning process that uses
animal brains or other fatty materials to alter the leather. The
resulting supple, suede-like hide is usually smoked heavily to prevent
it from rotting.
- Patent leather is leather that has been given a high gloss
finish. The original process was developed in Newark, New Jersey, by
inventor Seth Boyden in 1818. Patent leather usually has a plastic
coating.
- Shagreen is also known as Stingray skin/leather.
Applications used in furniture production date as far back as the art
deco period. The word "Shagreen" originates from France and
is commonly confused with a shark skin and stingray skin combination.
- Vachetta leather is used in the trimmings of luggage and
handbags, popularized by Louis Vuitton. The leather is left untreated
and is therefore susceptible to water and stains. Sunlight will cause
the natural leather to darken in shade, called a patina.
- Slink is leather made from the skin of unborn calves. It is
particularly soft, and is valued for use in making gloves.
- Deer Skin is one of the toughest leathers, partially due to
adaptations to their thorny and thicket filled habitats. Deerskin has
been prized in many societies including indigenous Americans. Most
modern deer skin is no longer procured from the wild, with "deer
farms" breeding the animals specifically for the purpose of their
skins. Deer skin is used in jackets and overcoats, professional
sporting equipment such as kendo bogu, as well as high quality
personal accessories like handbags and wallets. It commands a high
price due to its relative rarity and proven durability.
- Nubuck is top-grain cattle hide leather that has been sanded
or buffed on the grain side, or outside, to give a slight nap of short
protein fibers, producing a velvet-like surface.
There are two other descriptions of leather commonly used in specialty
products, such as briefcases, wallets, and luggage.
- Belting leather is a full grain leather that was originally
used in driving pulley belts and other machinery. It is often found on
the surface of briefcases, portfolios, and wallets, and can be
identified by its thick, firm feel and smooth finish. Belting leather
is the only kind of leather used in luxury products that can retain
its shape without the need for a separate frame; it is generally a
heavy-weight of full-grain, vegetable-tanned leather.
- Nappa leather, or Napa leather, is extremely soft and supple
and is commonly found in higher quality wallets, toiletry kits, and
other personal leather goods.
The following are not 'true' leathers, but contain leather material.
- Bonded Leather , or "Reconstituted Leather", is not
really a true leather but a man-made material composed of 90% to 100%
leather fibers (often scrap from leather tanneries or leather
workshops) bonded together with latex binders to create a look and
feel similar to that of genuine leather at a fraction of the cost.
Bonded leather is not as durable as other leathers, and is recommended
for use only if the product will be used infrequently. One example of
bonded leather use is in Bible covers.
- Bicast leather is a man-made product that consists of a thick
layer of polyurethane applied to a substrate of low-grade or
reconstituted leather. Most of the strength of bicast leather comes
from the polyurethane coating, which allows this material to be used
where strength or durability are required.
The vast majority of leather is sold according to its area. The leather
is placed through pin-wheel or electronic measuring machines and its
surface area is determined. The unit of measurement is square metre,
square decimetre or square foot. The thickness is also important, and this
is measured using a thickness gauge (the unit of measurement is
millimetres, e.g., 1.8 mm is a standard thickness for a school shoe).
In some parts of the world top-grain thicknesses are described using
weight units of ounces. Although the statement is in ounces only, it is an
abbreviation of ounces per square foot. The thickness value can be
obtained by the conversion:
- 1 oz/ft² = 1/64 inch (0.4 mm)
Hence, leather described as 7 to 8 oz is 7/64 to 8/64 inches (2.8 to
3.2 mm) thick. The weight is usually given as a range because the inherent
variability of the material makes ensuring a precise thickness very
difficult. Other leather manufacturers state the thickness directly in
millimetres.
