Alphabetical Search

#|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

R&D	See: Research & Development.
Raceway brining	Raceway, such as a tank shaped like a racecourse, in which brine solution and hides are moved around by a paddle, for brine curing of hides.
Radiation curing	Method of curing hides by radiation.
Rapid tannage	See: Quick tannage.
Rash	Skin reaction to insects, bacteria, chemicals etc. See: Dermatitis.
Raw hide lace	Buffalo hide, limed, unhaired, dried out and lightly oiled, cut into strips for the purpose of joining transmission belting.
Raw material	Unprocessed natural product used in manufacture.
Rawhide	A more or less translucent product, made from bovine hides, with the hair and flesh removed by liming, unhairing and fleshing, and dried out in the limed state, usually without any tanning treatment.
Rawhide trimmings	Pieces cut from raw hides or skins to give them a satisfactory shape.
Reactive dyestuff	Dyestuff that contains functional groups capable of forming covalent bonds with active sites in fibres, such as hydroxyl groups in cellulose, amino, thiol, and hydroxyl groups in wool or amino groups in polyamides. These are especially suitable for gloves and other garments required to withstand wet conditions and also dry-cleaning.
Reactive resin	Resin which contains reactive organic groups, that are capable of attaching to the fibre by chemical union.
Reconstituted leather	Made by forming leather fragments and fibres into sheet material with the aid of adhesives, resins, etc.
Recycle (v); recycling	Recovery and/or reuse of what would otherwise be a waste material.
Red heat	Red colouration found on the flesh side of salted hides after storage. Caused by salt tolerant (halophilic) bacteria that are aerobic so they stay on the surface of the hide. Long term storage of hides with red heat can lead to pitting of the surface. The origin of salt may influence the development of red heat, with marine salt containing high levels of halophilic bacteria compared to rock salt. Kiln dried solar evaporated salts have been found to be free of halophilic bacteria.
Reduced chrome liquor	Solution of trivalent chromium salts, mainly basic sulphates,  prepared by the reduction of a dichromate solution, by sulphur dioxide or by an organic substance, such as glucose, in the presence of acid; used for chrome tanning.
Re-dye (v); re-dyeing	Subject a previously dyed material (leather) to a second dyeing treatment, which could be in a similar or different colour.
Reed bed	Also called reed bed filters (RBF). The process does not rely on microbial degradation as a major process but uses the reactive/adsorptive potential of soil and the uptake by plants. A system successfully used for treatment of COD.
Reflesh (v); refleshing	To give hides or skins a second fleshing.
Refrigeration	1. The science of producing and maintaining temperature below that of the surrounding  atmosphere. 2. Extract heat from a body or substance by lowering the temperature of the body, such as a  hide or skin, and by keeping its temperature below that of its surroundings.
Rehydration	Absorption of water into dried hides, skins or leather.
Rein	Long, narrow leather strap, each end of which is attached to the bit and which is used to guide or check a horse.
Rejects	Hide, skin or leather of inferior quality to the established grades and usable only for poor quality articles or not at all.
Reliming	Second liming step.
Rendement	Yield figure for a vegetable-tanned leather calculated from its analysis, namely the weight of leather at 14 % moisture content per 100 parts hide substance.
Rendered tallow	Harder kinds of fat (melted down) obtained from cattle and sheep body tissue by rendering, using either a heat process or a heat and chemical process.
Render (v); rendering	1. Convert packing house (abattoir) waste, livestock carcasses and tannery waste, such as fleshings, into industrial fats and oils (for instance tallow for soap) and various other products (for instance fertilisers and protein supplement in feeding stuffs for livestock). 2.   Process of extracting, melting or clarifying fat.
Rendering plant	Unit for the treatment of animal carcasses and waste offal in order to recover products such as tallow. It is also a plant to treat some tannery waste (fleshings).
Repair bend	Sole leather bend produced for the repair of footwear. See: Manufacturing bend.
Replacement tannin	Synthetic tanning agent which can largely, or entirely, replace the vegetable tannins without fundamentally altering the tanning process or the character of the finished leather.
Resalted	Treated with salt for a second time to ensure thorough saturation and hence better preserving properties.
Research & Development (R&D)	Work directed towards the innovation, introduction, and improvement of products and processes.
Reset (v); resetting	Treatment to increase the area of the hide or skin for the second time. See: Set (v); setting out.
Reshaving	Giving hides and skins a second shaving to ensure a correct and level thickness. See: Shave (v); shaving.
Resin	Organic substance of natural origin, (exuded in the sap of trees and plants) with high-molecular weight, amorphous, and sticky. These substances could be insoluble in water, but soluble in several organic solvents.
Resin	Organic substance of synthetic resins, made by polymerisation or polycondensation, with similar properties to natural resins, such as the polyacrylates.
Resin binder	Material such as polyacrylate, for incorporation in a pigmented finish to fix the pigment and form a film.
Resin finished	Leather with a pigment finish, incorporating a synthetic resin binder.
Resin retannage	Second tannage with a resin, generally for filling purposes, applied in the post-tanning operation after the primary tannage.
Resin tannage	Deposition within the fibres of pelt, or leather, of high molecular, water-insoluble polymerisation, polyaddition or condensation, products without these and the fibres necessarily combining. Note: Resin tannin.
Resin tannin	High molecular weight organic polymerisation, or condensation, product deposited within the fibres of pelt or leather without combination necessarily occurring; introduced either as a water solution and deposited through subsequent growth of molecular size (urea or melamine/formaldehyde condensates, vinyl or acrylic compounds) or as water dispersions (dicyandiamide/ formaldehyde condensates); used for pre-tanning and for filling leather.
Resin top coat	Synthetic resin used as a film-forming agent to give a protective top coat.
Resinous spue	Resinous exudation onto the surface of leather, which may be difficult to dissolve in organic solvents.
Resist	Substance which is applied to the tips of the hairs of furskins to protect them from uptake of dye whilst the shafts are dyed.
Resist wax	Wax mixture applied to the elevated areas of an embossed leather to prevent these taking up dye. Note: Used in the preparation of  “antique” leathers.
Resistance to hydrolysis	Resistance of a compound to being hydrolysed.
Restraining action	Slow down the dye uptake, by means of certain ionogenic (inorganic and organic) auxiliaries.
Retan (v); retanning	Subject an already tanned leather to a further tanning treatment to modify its properties, using an agent of the same, or entirely different, type.
Retannage	Modifying second tanning treatment, applied to leather that has already received a primary tannage to modify some of its properties, using an agent of the same, or an entirely different, type.
Retanned leather	Leather which has been subjected to an additional tannage with similar or other tanning materials.
Retanning material	Substance of diverse chemical properties able to be used in the retannage to impart specific properties to the leather.
Reticular layer	The deeper layer of the dermis formed by interlacing fascicle of white fibrous tissue. See: Dermis.
Reticular tissue	The inner, thick, dense layer of the dermis that blends into the subcutaneous connective tissue. Reticular tissue, because of its netlike structure is also known as ‘fibre network layer’. The reticular tissue forms the major part of leather, hence the properties of leather depend to a considerable extent upon the condition of the reticular tissue in the finished leather.
Reverse calf	Water-resistant suede calf leather finished on the flesh side.
Reverse coating	Application of finishes by a roller coater where the print roll is counter-rotating to the leather fed through the machine.
Reverse lamb	High-grade gloving leather with a suede finish on the flesh side, made from the skins of slink or unweaned lambskins.
Reverse Osmosis (RO)	Filtration process which consists of applying greater pressure on the water than the osmotic pressure, in order to force the water to pass through a semi-permeable membrane against the direction taken by the natural osmosis process. This technique is used in the production of drinking water from salt or brackish water. It retains particles of between 0,01 nanometre and 1,0 nanometre.
Reverse side	Water-resistant suede side leather finished on the flesh side.
Rewetting	See: Condition (v); conditioning.
Rib lines	Generally not visible in the raw but become apparent mainly in the neck and shoulder when the skin is held up to the light in the limed state. See: Blind rib.
Ribbiness	Naturally occurring defect in woolled sheepskins, especially of the merino, finer wool types, consisting of numerous long, raised ridges on the surface, usually running across it in parallel lines from the backbone to the belly and flanks.
Ringworm	Naturally occurring defect in woolled sheepskins, especially of the merino, finer wool types, consisting of numerous long, raised ridges on the surface, usually running across it in parallel lines from the backbone to the belly and flanks.
Rinse (v); rinsing	Cleansing of a material with a stream of running water.
RO	See: Reverse Osmosis.
Rock salt	Common salt obtained by direct mining of underground deposits in contrast to that obtained by evaporation of brines or solar evaporation. Calcium, potassium and magnesium compounds commonly occur with rock salt.
Roll (v); rolling	Mechanical process after drying performed, for example, on vegetable tanned sole leathers. The purpose is to give the leather fibre structure a high density by high pressure to improve the stiffness and water resistance.
Roller coating	Application of finishes by a roller coater machine. Most advanced and most economical coating of leather.
Roller leather	Leather with compact structure, smooth, fine grain, of high resistance to abrasion, smooth flesh side and firm feel; made from chrome, chrome/synthetic or synthetic tanned calfskins or sometimes sheepskin, for high draft belting in cotton spinning machinery, or from skins of calf or close structure sheep, mainly in natural colour or dyed red for covering rollers in such machinery. When used for belting it is sometimes interlaid with different colour synthetic materials. Uniform thickness of a tolerance not exceeding ± 0,05 mm is essential.
Rope damage	If rope is used for tying bundles of hides and skins for shipping, the rope should be oil-free. Oiled rope may form stains on the hides which will show in the finished leather.
Ross	Outer, scaly layer of the bark of older trees.
Rough tanned leather	Leather which after tanning has not been further processed. Note: It can be in a damp or dry condition. Differentiation is made between (a) wet blue leather which has not been fat-liquored and is in a damp condition and (b) crust leather which has been vegetable, chrome or combination tanned and which has been dried. In the UK the term "rough tanned" is used chiefly in connection with vegetable tanned hide leather, such as rough tanned strap butts. See: Crust leather.
Roughing	Imparting a rough surface by abrasion.
Roughness	Rough surface feel to the finish of the leather. Possible causes are poor buffing, contamination in the finish, solvent finish too dry Note: The solvent evaporates even before the finish reaches the surface of the leather, etc.
Round feel	Term used to describe the feel of a leather which is full, soft and flexible.
Rove	Apple-like gall on Quercus infectoria, produced by insect Cynips insana.
Rub (v); rubbing	To polish or abrade a material.
Rubbed grain	Grain enamel that has been damaged by bacterial, mechanical or chemical action. See: Low grain/sueded grain.
Rubbing off polishing	See: Brush off.
Run (v); running	Paddle or drum goods, continuously or intermittently, to treat hides and skins in different operations in beamhouse, tanning and post-tanning.
Run mark	If concentrated chemicals come into direct contact with hides or skins, damage can be caused. This damage is seen in the form of run marks where the concentrated chemical has spread over an area of the hide. Note: Alkali, acid or chrome run marks.
Run pelt	Sheepskin dewoolled by sweating whose grain and flesh surfaces have become pitted, or liquefied, in spots by a worm-like organism.
Russet leather	Vegetable tanned cattle hide leather which has been dressed ready for staining or finishing. Note: In Austria see: Cowhide. In France this term is also applied to finished leather. In the UK sometimes termed "skirt leather". The leather may now be combination or chrome tanned.
Russia calf	A calf leather tanned with the bark of willow, poplar and larch, curried on the flesh side with a mixture containing birch tar oil which gives it a characteristic odour.
Russia leather	Smooth finished, dyed side or calf leather scented with birch tar oil, vegetable tanned and made in imitation of the old-fashioned genuine Russia calf. Now also chrome or combination tanned and given water-repellent properties.

Search for a glossary term