Glossary: Leather

A


Altered Leather
Leather that has had the original surface of the skin removed (usually due to imperfections in the original surface) and a new grain embossed into the leather. This is also called corrected grain. Most top grain leathers have altered or corrected grain surfaces.

Aniline
A colourless oily liquid made from coal tar used in making dyes and resins in organic synthesis.

Aniline Dye
Any dye produced synthetically from coal tar products.

Aniline Dyed or Aniline Leather
Leather that has been dyed in a dye bath with some level of dye penetration.

B


Bark Tanned
Leather that has been vegetable-tanned mainly by means of tannins from the bark of trees.

Base Dyes
Common (usually lower grade) dye colours used in custom coloured leathers that are quickly made. Hides are dyed in advance awaiting the spray application of custom colours.

Blues, in the
The state of hides that have been tanned once using chromium salts. These hides are light blue in colour.

Bovine
An animal belonging to the cattle or ox family.

Breathability
An important characteristic of a full grain leather. Due to its intact grain and pore structure, full grain leather breathes. This means that the leather adjusts to temperature and wicks away moisture and body heat, making it very comfortable to sit on.

Brush Colouring
The process of applying dyestuff to the leather by means of a brush. In this cosmetic process dyes are not saturated into the hide.

Buffed Leather
Leather from which the grain is removed by an abrasive or bladed cylinder. This process is used in altered or corrected grain leather.

C


Chrome Tannage
Leather tanned with chromium salts resulting in soft, mellow hides receptive to excellent colour variety.

Combination Tannage
Leather that receives chrome and vegetable tannage producing suppleness and body in the hide.

Corrected Grain
Commonly referred to as top grain. Lacking an intact full grain surface. Usually pigmented.

D


Degrained Leather
Leather from which the grain has been removed after tanning, by splitting, abrading or other processes.

Drum Dyeing
The application of dyestuffs to leather by the immersion of the leather in a drum that is tumbled. This process allows full dye penetration into the fibre.

E


Embossed Leather
Usually corrected grain, in which a pattern is applied by extreme pressure in a press to give a unique design or imitation of full grain characteristics. Sometimes leathers are embossed to make them appear to be another leather, such as embossing an alligator pattern into cowhide.

Enhanced Full Grain
Full grain leather, which has received minor surface alteration to improve grain appearance.

F


Fat Wrinkle
Wrinkles in the grain of leather caused by fat deposits in the animal that create beauty in the leather. Fat wrinkles are not visible in imitation grain leather.

Finish
Generally defines a surface application on the leather to color, protect or mask imperfections. More specifically, it refers to all processes administered to leather after it has been tanned.

Full Grain
Leather in which the grain layer or dermis has not been altered. The grain layer gives each type of leather its distinctive appearance.

Full Hand
This defines leather that is full bodied and robust. Also called round hand or full round hand.

G


Grain (leather)
The outside of the hide or skin consisting of the pores, cells, wrinkles and other characteristics which constitute the natural texture of the leather.

Grain Character
The natural markings on the surface of the leather.

Grain, Embossed
An artificial grain pressed into the surface of top grain leather from which the original grain has been removed.

Grain Sueded
A buffing process to raise the fibres on the grain side of a hide or skin to produce a velvet-like effect. This is also known as 'Nubuck' leather.

H


Hand
A leather industry term used to describe the feel, i.e. suppleness or fullness of upholstery leather.

Hide
The pelt of a large animal.

K


Kip
The hide from a grass-fed, immature bovine.

L


Leather
An animal hide that has been preserved and dressed for use.

Leatherette
A manufactured product that imitates leather.

Liming
This process includes removal of the hair, preparing the hides for the tanning process.

M


Matte Finish
A flat or dull finish.

Milling
A process that produces suppleness in hides.

N


Naked Leather
A dyed leather that has received no topical application that may mask or alter the natural state of the leather.

Natural Grain
A leather that retains the full, original grain.

O


Oak Tannage
Originally the tannage of leather was almost entirely with oak bark, later the term applied to tannage with a blend containing oak tannin. Now, it is loosely applied to any tannage of heavy leather with vegetable extracts.

Overtannage
See Retannage.

P


Papillary
The upper portion of the hide that has been separated from the reticular or split layer.

Patent Leather
Leather with a glossy impermeable finish produced by successive coats of drying oils, varnish, or synthetic resins.

Patina
A natural characteristic that develops on full grain leather through normal use over a period of time.

Perforated
In leather, this is the process of die-cutting small holes to form a pattern. The holes can vary in size, density and pattern.

Pigmented
Leather that has been sprayed with a pigmented, opaque finish.

R


Rawhide
Untanned or partially tanned cattle hide.

Reconstructed Leather
Material composed of collagen fibres, obtained from macerated hide pieces, which have been reconstructed into a fibrous material.

Retannage
A modifying secondary tannage applied after intermediate operations following the primary tannage to further enrich and enhance the quality of the leather.

Round Hand
A full-handed leather, usually slightly swelled through tannage and fat liquoring.

S


Saturation
A most important aspect in producing high quality leathers. Full saturation of tanning, fat liquors and dyes are essential in the production of fine leathers.

Shrunken Grain Leather
A full, natural grain leather that is shrunken to enlarge and enhance the grain character of the leather.

Side
Half a hide cut along the backbone.

Side Leather
Hides that have been cut in half, forming two 'sides' in order to better accommodate small tannery equipment.

Shave
Hides are shaved to a particular thickness after tannage by a large shaving machine. The excess is removed from the bottom of the hide.

Skive
To slice or split into a thin layer, or to reduce leather to a specific thickness.

Snuffed
The grain surface is abraded with brushes, emery wheel or sandpaper. Leather is snuffed for the purpose of removing defective grain or sueding the surface of the leather.

Split Leather
Leather made from the bottom split, or reticular layer of the hide, which has an imitation grain embossed into a heavily finished pigmented surface to simulate papillary leather.

Splitting
Cutting leather into two or more layers preparatory to tanning.

Strap Leather
Heavyweight, vegetable-tanned leather used for industrial purposes or to support seats and backs on certain types of seating.

Suede
A fibrous leather, typically made from the reticular part of the hide.

Sueding
The process of raising fibres on the grain side of a hide to give a velvet nap effect. This is generally called 'Nubuck' or 'grain sueded.'

T


Table Dyeing
The application of dyestuff to leather with a brush; the leather being laid on a table. Also called brush colouring.

Table Run
Leathers that are not graded.

Tannin
Any various solvent, astringent substances of plant origin used in tanning leather.

Top Grain
An over-used term commonly used to refer to corrected grain leather. See Corrected Grain.

Trim
The removal of the outer edges of the hide not suitable for making leather.

U


Unfinished Leather
Normally defines aniline dyed, naked leathers with no additional application intended to finish, colour or treat in any way that would alter the natural characteristics of the leather.

Upholstery Leather
A general term for leather processed for many uses including applications, etc.

V


Vegetable Tanning
The conversion of rawhide into leather by use of vegetable tannins. This process produces leather with greater body and firmness than the more general method of chromium tanning.

W


Weight
The weight of leather is measured in ounces per square foot.

Wet Blue Leather
Leather that after chrome tanning has not been further processed and is sold in the wet condition.