LEARN ALL ABOUT LEATHER
Leather A-Z
A fantastic A – Z of leather terms helping you to learn all about leather, what it is and how it is produced
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
ANILINE
The name of a dye used to colour leather, penetrating the hide throughout
Non toxic dyes are used
Aniline is not a type of leather but the term is often used to describe sensitive leathers
Aniline dyed leathers will be the same colour throughout unless a pigment or other substance has been used to colour the top surface
See also:
What is Aniline Leather?
Aniline Dyed Leather
ANILINE DYED
Process of colouring leathers throughout using coloured non-toxic dyes
The correct name for ‘Aniline’ leather
The leather has been through-dyed in a dye bath (drum dying) and has not received any coating of pigment or finish
As it is so sensitive in its natural state it often receives extra surface treatments in order to make it more serviceable
See also:
What is Aniline Leather?
ANILINE FINISHED
An aniline dyed or natural leather that has been finished with a surface coating, clear or coloured with dyes
ANTIQUING
The application of a contrasting colour (usually darker) over a base colour on the surface of the leather to accentuate the natural grain or embossing
May be applied by hand or machine
Commonly used on Chesterfield style furniture
BI-CAST
A split leather with a polymer coating
The polymer coating is created as a separate layer and then applied with adhesives, rather than being applied by spraying several thin coats as in ordinary leather
This results in a very even finish on leather of generally poor quality
The thickness of the polymer layer will determine whether it can be sold as leather
See also:
What is Bicast Leather?
BONDED LEATHER
Hides or skins that have been tanned are then disintegrated mechanically or chemically into particles or powders and are then bonded into sheet form which is then coated in a variety of ways to imitate leather
As the leather has been disintegrated these sheets are not leather and Bonded Leather cannot be sold as leather
BUFFED
Leather which has some of the top grain removed by mechanical sanding and abrasion
Used mainly on Aniline dyed leathers which are to be pigment coated or to create a softer feel to Aniline leathers
Full-Grain leather will be buffed to create Nubuck Leather
CHROME TANNED
99% of all upholstery leather is chrome-tanned
Leather tanned with Chromium Salts
Chrome tanning involves drumming the hide in a bath of chrome liquor
After this process, the hide is called a ‘wet blue’
Chrome Tanned leather is ‘duck egg’ blue in colour
COATED LEATHER
A product where the surface finishes that have been applied does not exceed a third of the total thickness of the product but is in excess of 0.15mm
Could also refer to Patent Leather
CORRECTED GRAIN LEATHER
The leather on which the outer surface of the grain has been lightly removed by sanding or buffing and then a new surface has been added with finishes
Usually followed by embossing
This leather generally has a pigment coating and is a then protected (finished) leather
CORRECTED
A new grain pattern is printed (embossed) into the finishes on the leather surface
CROCKING
Transferring of a colour or finish from leather to other material by rubbing or abrasion
CRUST
Leather that has been through the tanning process, aniline-dyed and dried, but with no surface finish
DRUM DYED
A dyeing process in which the leather is immersed in dye
The leather is placed in a drum with dyes and tumbled to ensure the complete absorption of colour
EMBOSSING/EMBOSSED LEATHER
Creating a motif or texture on the leather by impressing a pattern on the surface of the hide
A very even and uniform pattern is created and this may be done to disguise defects or blemishes or to create visually pleasing designs or textures
This can replicate the grain pattern of an animal or be something unrelated ie: Box print or Paisley
FAT LIQUORING
The process of replacing oils that have been leached from the hide during processing
Takes place in the re-tanning process and leaves the leather soft and supple
Fat Liquors are bonded to the fibres
FAT WRINKLES
Natural wrinkles in the leather that are a part of the unique qualities in the hide and usually found on the neck and belly areas of the hide
Fat Wrinkles are only visible in top grain leathers
FINISH
This term encompasses all procedures that are carried out after the tanning and initial dyeing process
These may include rolling, spraying, waxing, milling, buffing, embossing, antiquing, and the adding of any protective finishes
The term is also used to describe the surface appearance of the leather which maybe Matt, Gloss, Velvet etc.
FINISHED SPLIT
A split leather that has been finished with a surface coating to replicate the appearance of a grain leather – most commonly used on the outside back and arms of furniture
FULL ANILINE
Leather receiving its colour from dyes and with the top grain intact
May have topcoats of wax, oil or finishes to make the leather more serviceable
FULL GRAIN
A hide which has not been mechanically buffed or embossed
It may or may not have a pigment coat
The outer layer is taken from the hair side of the hide with nothing except the hair and surface debris removed
This still has the original grain surface intact and exhibits natural marking and characteristics
May also be referred to as Full Top Grain.
GRAIN
The outer surface of a hide or skin
It also refers to the pattern of the outer surface after the hair has been removed and will be peculiar to the animal that the skin or hide it has come from
The grain may be very natural as in Full Grain or maybe an imitation grain achieved by embossing
HAND
The term used to describe the feel or degree of softness of a hide or skin
HIDE
Term used for the skins of large animals such as cows, buffalo, elephant, camel etc
HYDROPHOBATED
Leathers which have been hydrophobated are water-resistant (waterproofed)
However, once anything has been added to water the leather will no longer resist it
LEATHER
The hide or skin of an animal that has been through the tanning process turning it into a non-perishable material
The hair or wool may or may not have been removed
If the leather has a surface coating applied the thickness of this surface (however applied) has to be 0.15mm or less
If the tanned hide or skin has been disintegrated and reformed this cannot be classified as leather ie: Bonded Leather
LIMING
The process of removing the hair from a rawhide through the use of chemicals prior to the Tanning Process
MATT FINISH
A leather that has a dull finish applied to the surface of the leather
MICRO-PIGMENT
This type of Aniline leather has a fine spray of pigment or finish added to the top surface to limit the natural hue variations of aniline-dyed leather and make it more serviceable
It may look very like pigmented leather but will react more like an aniline
Often referred to as Semi-Aniline (this term is often incorrectly used)
MILLING
Process in which tanned hides are tumbled in rotating drums with a combination of heat and a misting of water to soften the hand
NAKED LEATHER
A tanned aniline-dyed leather with no surface treatment
Commonly referred to as ‘Pure Aniline’
NAPPA LEATHER
Soft Full Grain Leather originally produced form unsplit sheepskin or lambskin for gloving and clothing but now also made from the Full Grain split hide
NATURAL GRAIN
Leather whose grain has not been altered in any way and the natural appearance of the grain is apparent
NITRO-CELLULOSE
A finish which is applied to Aniline leather
The nitro-cellulose finish is not the same as a polyurethane finish
It is less durable than polyurethane, but it is softer and leaves many of the aesthetic characteristics of Aniline leather
NUBUCK
A Full Grain Aniline dyed leather with a ‘suede-like’ nap effect created by removing the top hair cell layer by a buffing process
Softer than Suede
PEARLISED
A special finish giving a mottled appearance with a variation of sheen and hues
PIGMENTED
Leather whose surface is coated with a material containing pigment or other opaque materials
May also be known as Protected or Finished
POLISHING
Removal of the grain, scars and blemishes from a hide
May also be known as buffing
PROTECTED
Leather in which special chemicals have been introduced to prevent deterioration from polluted atmospheres
Leather whose surface is coated with a material containing pigment or other opaque materials
May also be known as Pigmented or Finished
PULL-UP
Refers to leather that derives its colour from dyes, waxes, and/or oils
When the leather is pulled during upholstery the oils/waxes dissipate and become lighter in areas which are stretched
Often sold as Aniline leather by retailers
PURE ANILINE
Leather which receives its entire colour from dyes only and exhibits natural markings and characteristics
SAUVAGE/KELA
A two-tone effect which adds depth and character
Can be tone-on-tone or a contrasting effect
SEMI ANILINE FINISHED
Leather that has been Aniline dyes incorporating a small quantity of pigment but not enough to conceal the natural characteristics of the original hide
See also Micropigment
SPEW
When the fat liquor introduced during the tanning process is destabilised and rises to the surface of the leather creating a white haze or film on the surface
This will have a greasy/fatty feel to it
Often looks like salts on brickwork
Requires a stabilising product to rebalance the fats
See also:
Spew – Not what you think!
SPLIT
The underneath layer of the hide after the splitting operation
Hides are often split into two or more thicknesses and a split is the bottom layers that are ‘split’ from the top
They are weaker and less breathable than top grain leather
Splits may be coated and embossed to simulate a top grain, or laminated (bi-cast)
SUEDE
The reverse side of any leather produced from the flesh split and has a rougher feel
The reverse side (or suede side) of top grain leather is termed ‘Hunter’
TANNING
The process of turning rawhide into leather
This process uses tanning agents to convert the hide into a stable non-perishable material
There are several types of tanning process including Chrome, Veg, Alum, Mineral and Oil depending on the tanning agents used which will produce different types of leather
TOP COAT
Synthetic transparent or coloured polyurethane resins applied as a protective coating producing a high gloss, semi-gloss(satin) or matt finish
TOP GRAIN
The outermost layer of the hide which is left after the splitting of the hide into layers
The top grain of the hide is strong, flexible and the most breathable part of the hide
It is also the part of the hide which will show the life of the animal through natural markings
Top Grain may be either natural (Full Grain) or Corrected
TUMBLING
A process in which tanned hides are placed in drums with heat and water and tumbled to the desired hand
Also called milling
UNFINISHED LEATHER
Leather that has been tanned, but to which no surface treatment has been applied
Synonymous with naked leather or pure aniline leather
VEGETABLE TANNED
Leather tanned with vegetable tanning agents
The process takes a lot longer than Chrome tanned leather
All About Leather is part of a series of articles taken from the Complete Guide to Leather compiled by Judy Bass Technical Director and Leather Instructor at LTT Leathercare Ltd