Aniline leather is a type of leather dyed exclusively with soluble dyes without covering the surface with a topcoat paint or insoluble pigments. The resulting product retains the hide's natural surface with the 'grain', i.e. visible pores, scars etc. of the complete original animal's skin structure.
Typically, leather is dyed both for aesthetic reasons and to conceal blemishes. The dye colors leather without producing the uniform surface of pigmented leather. Any visible variations on the surface of the undyed leather such as natural blemishes will remain visible.
There are different kinds of aniline leather, but the same kinds of dyes are used in the process. The dyes used are clear and transparent chemicals that allow the grain structure of the leather to be seen. These dyes show the natural texture, but do not protect the leather from damage.
Aniline leather may be referred to as full aniline or full sauvage leather to differentiate between this dye treatment and variants. Semi-aniline leather is produced through a very similar process to full-aniline, but has a thin protective top coat added to protect it from wear and staining. Pull-up aniline leather has additional oil or wax applied to the leather to give it a distressed look.
BASEBALL LEATHER-Leather used for the covers of baseballs. Prior to 1974 baseballs are covered in cowhide; today quality baseballs are covered in alumtanned horsehide.
BELTING LEATHER-The vegetable-tanned leather used in the construction of furniture and other strength-related requirements.
BLUE, IN THE-The state of hides or animals being "chrome" tanned after they have been removed from the tanning solution. Chromium salts cause the tanned hides to be light blue before they are dyed.
BOARDED LEATHER-Leather softened by creasing the grain by folding to and fro across the hide, either by hand or boarding machine.
BOAR DY-An adjective applied to stiff, inflexible leather. This term is not to be confused with boarding, which is the process of softening leather.
BRUSH COLORED-The application of dyestuff to leather with a brush, the leather being laid on a table.
BUFFED-Leather which has been abrased or sueded. This can also be referred to as snuffed, nubuck leather, or grain-sueded leather.
CASE LEATHERING-A general term for leather used in traveling bags and suitcases. The staple material for case leather is bovine hides.
CENTER CUT SUEDE-A suede split that has had the edges trimmed to leave the bends and the shoulder, leaving the best and most usable part, or the center of the material.
CHROME TANNAGE-Leather tanned in chromium salts, primarily basic chromium sulfate resulting in soft, mellow hides receptive to excellent color variety. Currently the most widely used tannage in the USA.
COMBINATION TANNAGE-Leathers tanned with more than one tanning agent, such as chrome and vegetable together, resulting in both softness and body in skins.
CORDOVAN-Leather made from the tight, firm shell portion of horse butts. Cordovan has very fine pores and a characteristic finish, and is very durable.
CORRECTED GRAIN-The outside skin is sanded or abraded to minimize faults. It is then pigmented to cover the sanding and printed with an artificial grain. A spray sealer topcoat is then applied. Corrected grain material is usually called top grain leather.
CROCK (noun)-The coloring matter that rubs off of poorly dyed leather.
CROCK (verb) -To transfer color of rubbing.
CROCKPROOF-Leather, suede or fabric that has been treated to prevent color from rubbing off. With suede, this term also means to treat to prevent shedding or rubbing off of fibers.
CRUST-Leather which has been tanned but not finished. Such leathers referred to as being "in the crust."
DEGRAINED LEATHER- Leather from which the grain has been removed after tanning, by splitting, abrading or other process.
DOUBLE BUTT SUEDE-A term sometimes used to mean center cut suede.
DRAWN GRAIN-Shrunken, shriveled, or wrinkled grain surface of leather.
DRUM DYING-The application of dye stuffs to leather by the immersion of the leather in a drum that is tumbled. This process allows full dye penetration into the fiber.
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.
EMBOSSED, FANCY-A fancy or geometric pattern is impressed into the leather.
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-A surface application on the leather to color, protect, or mask imperfections. More specifically, all processes administered to leather after it has been tanned.
FULL GRAIN-The term used for the outside original skin or hide which has had the hair removed, but otherwise has not been corrected or altered. Full-grain leather possesses the genuine original grain of the animal.
FULL HAND-Leather which is full-bodied, such as some combination tanned leathers and fine vegetable-tanned upholstery leather. Also called round hand.
GLOVE LEATHER-A term used to describe soft leather used for gloves, which is normally lambskin. The term is also used by some to define soft leather.
GRAIN (LEATHER)-The outside of the hide or skin consisting of the pores, 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.
GRAINED LEATHER-Any leather on which the original natural grain has been changed or altered by any method, process or manipulation; also top grain.
GRAIN SUEDED-A process of sueding the grain side of the skin to achieve a buffed or sueded condition. See "Snuffed".
HEAVY LEATHER-A somewhat indefinite term, generally understood to include vegetable-tanned sole, belting, strap and mechanical leathers made from unsplit cattlehides.
IMITATION-A variety of materials which have been made to resemble genuine leather. The great bulk of these are rubber or plastic-coated fabrics. It is unlawful to use terms connoting leather to describe imitations.
LEATHER-An animal skin which has been preserved and dressed for use.
LEATHERETTE-A manufactured product which imitates leather.
MATTE FINISH-A flat or dull finish.
MINERAL TANNED-Leather which has been tanned by any of several mineral substances, notably the salts of chromium, aluminum, and zirconium.
NAKED LEATHER-A leather with no surface, impregnated treatment of finish other than dye matter which might mask or alter the natural state of the leather.
NATURAL GRAIN-A leather which retains the full original grain.
NUBUCK-A brushed, grain-sueded leather.
OAK TANNAGE-Originally, the tannage leather occurred 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 leather with vegetable extracts.
OIL TANNED-Leather tanned with certain fish oils. Produces a very soft, pliable leather such as chamois.
PATENT LEATHER- Leather with a glossy impermeable finish produced by successive coats of drying oils, varnish, or synthetic resins.
PATINA-A surface appearance of something grown beautiful, especially with age or use; an appearance or aura that is derived from association, habit, or established character.
PERFORATED-In leather, the process of die cutting small holes to form a pattern. The holes can vary in size, density and pattern.
PIGMENTED-A process of coloring and coating in the leather surface with colored pigments dispersed in film-forming chemicals called binders which can be tailor-made to produce surfaces that are highly resistant to wear, fading, etc. Leather that has been sprayed with a pigmented, opaque finish. This is usually done to cover imperfections in leather
PLATING, PLATED LEATHER-Pressing leather with a heated metal plate under high pressure. Most furniture leather is usually sanded, pigmented and plated to cover imperfections.
PRODUCTION RUN-Cheaper, ungraded leather sold to manufacturers for use on furniture.
RECONSTITUTED LEATHER-Material composed of collagen fibers obtained from macerated hide pieces, which have been constructed into a fibrous mat.
RETAN-A modifying secondary tannage applied after intermediate operations following the primary tanning.
ROUND HAND-A full-handed leather, usually slightly swelled as with vegetable tanning.
SHRUNKEN GRAIN LEATHER-A full, natural-grain leather which is shrunken to enlarge and enhance the grain of the leather.
SHOULDER LEATHER-The thickest part of the hide from the shoulder area of the cow.
SIDE-Half a hide cut along the backbone.
SIDE LEATHER-Grain leather which has been cut in half, forming two "sides" in order to better accommodate tannery equipment.
SKIVE-To shave, slice or divide, to peel into a thin layer.
SNUFFED-The grain surface is abraded with brushes, emery wheel or sandpaper. Leather is snuffed for the purpose of removing defective grain, or for sueding the surface of the leather.
SPLIT LEATHER (SPLIT)-Skin sliced in layers to give uniform thickness to the piece (grainside). Split leather (inside) is trimmed and finished as suede. Cheap leathers are sometimes pigmented splits with embossed imitation grain.
SPLITTING-Cutting leather into two or more layers, or cutting leather into two sides preparatory to tanning.
SPREAD-The size of a skin measured by machine in square feet.
STRAP LEATHER-Heavyweight vegetable-tanned leather used for industrial purposes, or to support seats and backs on certain types of seating.
SUEDE-Leathers that are finished by buffing the flesh side (opposite the grain side) to produce a nap. Term refers to the napping process, and is unrelated to the type of skin used. See "Split Leather".
SUEDING-The process of raising fibers on the grain side of a hide or skin to give a velvet nap effect. This is generally called "nubuck" or "grain suede."
TABLE DYEING-The application of dyestuff to leather with a brush, the leather being laid on a table. Also called brush coloring.
TABLE RUN- Leathers which are not graded. See "Production Run".
TANNIN-Any various solvents; astringent substances of plant origin used in tanning leather.
TOP GRAIN-The term intended to define genuine grain leather, as opposed to split leather which has been pigmented and embossed with a new grain. In reality, top-grain leather usually has had the original grain removed and an imitation grain embossed into the surface.
TRIM-The removal of parts of a skin or hide not suitable for making leather, such as portions on the outer edges.
UNFINISHED LEATHER-Normally defines aniline-dyed, naked leathers with no additional application intended to finish, color or treat in a way that would alter the natural characteristics of the leather.
UPHOLSTERY LEATHER-A general term for leather processed for use in furniture, automobiles, and airplanes.
VAT DYEING-An older method of dyeing leather sometimes confused with drum dyeing.
VEAL CALFSKIN-An upholstery leather skin averaging 30 square feet of premier quality.
VEGETABLE TANNING-The conversion of rawhide into leather with a greater body and firmness than the more general method of chromium tanning.
WEIGHT-The weight of leather is measured in ounces per square foot.
WICK-To absorb and dissipate moisture and heat through the fiber structure of the leather.
PRIMER POINTS (Courtesy of Spinnebeck) "The most confusing term used within the leather industry is the term 'top grain'. Ironically, 'top grain' is the definition generally used when the grain is not genuine; when, in fact, the real grain has been taken away and an imitation grain embossed into the leather. When the genuine grain remains, the leather is called 'FULL Grain' or 'FULL TOP Grain'."
The better the quality of a hide of skin , the less it has to be treated. In a premium quality hide or skin the full natural grain is retained and exposed. One should see the "fat wrinkles," the natural markings, and the feel or hand should be supple and natural to the touch.
Although calfskins are finer than the hides of older animals, they are equal in durability and abrasion resistance because the fiber structure of calfskin is denser, tighter and stronger than that of cowhide. (Some disparity in opinion exists over the relative quality of European hides and skins versus American hides or skins. However everyone agrees that hides or skins in descending order of quality are: calfskin, premium cowhide, premium suede, select cowhide and production run cowhide.)
Transforming hides and skins into leather is done in three basic phases: pretanning, tanning, and finishing. Whatever is done to a piece of leather after it is tanned is part of the finishing process. This may include: dyeing, rolling, pressing, spraying, plasticizing, lacquering, antiquing, waxing, buffing, snuffing, embossing, glazing, waterproofing, stainproofing, flameproofing, or any other post-tanning treatment. Full-grain leathers are color-treated only by transparent aniline vegetable dyes which shade or color the skins without concealing or obscuring natural markings or grain character. Most furniture leathers have been treated with a coating of pigmentation to help even out the color.
Although many finish applications are administered for purposes other than altering or masking the surface of the leather, all applied opaque finishes and airtight surface sealants should be held suspect. Genuine, natural, unpigmented and unplasticized leather will breathe and ventilate, thus wicking away body heat. If upholstery leather is able to breathe, it can absorb moisture, be nourished, and remain soft and pliable. If the surface of the leather has been plasticized, as is the case for most automobile upholstery, the leather cannot breathe and may become stiff and boardy.
Kinds of leathers
The above information is provided courtesy of Ekornes - makers of
The Stressless? Chair.