Aniline and pure aniline – Terms which describe a leather with a natural surface, full grain, without any pigmented covering. The terms aniline derives from the fact that the leather has been dyed in a drum with synthetic colourings, known as aniline.
Asportato – This is an effect which is possible to note on the surface of the hides generally used in upholstery and leather goods: this operation is performed manually with a buffer soaked in a solvent of a particular finish in order to re-create on the finished piece a typical effect of ageing.
Automotive leather – We define this as the type of leather used for the covering of the car interiors, using big hides, with precise technical qualities of resistance.
Banks works – These are the preliminary operations to the real tanning process: the resoaking, depilation, decalcination, maceration, pickling and tanning. The definition derives from ancient times in which these operations were carried out on the banks of a river.
Basil – It is a type of leather in a intermediate level of process, partially greased and generally of a neutral colour; it is synonymous with crust. In ancient times it was like a vegetable tanned skin, neither greased nor dried and therefore it was biscuit colour, typical of the vegetable tanning.
Blowing – It is the tendency of the derma to detach from the fibre substrate, creating a rather unattractive “orange peel” effect.
It is usually considered a defect, but in fact a distinction has to be made between natural (and inevitable) blowing, in the flanks and legs articulations areas, and the blowing caused by processing problems, usually over-strong buffing or excessive dressing.
Blue scale – It is a sample scale made of eight blue colourings with increasing light fastness, used to evaluate the light resistance of the finished hides.
Buffing – In order to prepare the hide for a regular absorption of the refinishing and to remove the grain defects, the leather is smoothed on its surface using a grade of emery paper depending on the article and the degree of imperfections to eliminate.
Bulgaro – A synonym of Russian leather: this type of leather was mainly produced in Russia with veal or horse hides, using willow rinds, rue extracts and birch tar, which gave a particular brown-red colour.
Bycast – It is a term put in the tanner language at the beginning of the 80's. It defines a type of crust together with a polyurethane film which reproduces the image of the grain of a leather in full grain.
Collector – It is the person who collects from the slaughterhouses the raw hides from different animals in order to sell them to the tanneries.
Conservation – After being flayed, the hide passes through salt or brine in order to protect it from the degrading influence of micro-organisms and to grant a longer stocking time.
Croupon – This is how we define the central part of the bovine hide. Croupon has an important role in the production of sole-leather
Crust -> See Basil
Cuoietto – Leather obtained from chrome tanned bovine which simulates vegetable tanning.
Drum – Basic machine for the tanning, the drying and the greasing of the hides. In ancient times, it was built with just hard wooden staves held together with iron hoops, but today is made also of steel or resin. It is a cylinder which rotates on its axis, like the drum of a washing machine even if the dimensions are a little bit different. Normally it has an opening for the insertion of the hides and a steel lid closing; products for the process enter the drum through the axis rope. The rolling movement of the hides in the process liquids gives an acceleration and homogenisation of the chemical and physical process.
Drummed – It is a generic term which defines a type of soft leather with a grain in relief due to the long action of the dry fulling mill in the finishing phase.
Drumming – See Fulling
Drying – Through this operation humidity is removed from hides which have just finished the tanning, in order to prepare them for the next finishing operations. The methods used are the loom and in a vacuum.
Dying – Dying is made in a drum with metal-based liquids for colouring, making the colour penetrate through the section (passing dyeing) .
Finishing – It represents the final part of the tanning process. It is a sort of make up of the hides, subject to the whims of fashion or due to precise technical requests. Every article has its own formula and its own finishing procedure. It is an operation carried out with sprinkling plants using particular resins, pigments, colourings, and wax.
Flame-retardant – Type of leather which is fire resistant. This leather is requested for the interiors of aeroplanes, cars, boats.
Fleshing – These are the shreds presents on the skin in the inside of the skin (opposite to the grain), after the flaying of fat and muscle substances.
Fulling mill – This is a dry operation carried out in rolling drums and gives smoothness and grain to upholstery leather.
Grain – It is the surface picture in the grain side of leather; grain can be made more or less evident by using the fulling mill and depending on the requested processes. This is called “natural grain”
When the leather has an irregular grain or has undergone a buffing process, a new grain has to be applied by printing: therefore in this case it is called “printed grain”.
Greasing – Essential operation of lubrication of the hide through natural or synthetic oils. Greasing is necessary for almost all type of leathers, adding smoothness; without this process leather, when dried, becomes rigid and easily breakable.
Grey scale – It is a sample scale made up of ten grey shade images with increasing brightness, each one side by side with a reference darker grey. The first level of the scale (5) shows two identical greys, then, through intermediate levels (4/5, 4, etc.) it comes up to the last level, 0/1, where the two greys are the most different. It is used to evaluate rubbing resistance and ageing by heat.
Heifer – A female bovine which has never been pregnant. Heifers have a smaller but firmer belly, while cows (which have already been pregnant) have wider and looser flanks.
Leather – Leather is the principle product of vegetable tanning . Today, sole leather is produced both by slow and fast tanning. Slow tanning in tanks permits us to obtain leathers of much higher compactness and a better exploitation of the tanning soakings, and consequently a minor environmental impact. On the contrary it takes a long time, more than three months, and therefore a huge quantity of money. Fast tanning instead, gives the opportunity to process in two weeks. After a short period in tanks with tanning soakings, hides go through drums filled with gradually strengthening tanning solutions. Fast tanning is better suited for the production of light, soft leathers.
Leather goods – Leather used principally for handbags. It is obtained from bovine hides chrome or vegetable tanned, finished in lots of different ways, depending on current fashion.
Limed leather – It is leather depilated and fluffed before being tanned. Technically the leather is at the purest possible level and theoretically it should be composed solely of pure derma substance and water. The hide looks and feels like the tripe we eat: gelatinous, turgid and whitish.
Liming – This is the chemical or enzymatic process which is used to remove hairs and the epidermic layer of the skin.
Lining material – It defines low compactness hides for the internal lining of shoes. It optimises the use of low quality selection of bovine, ovine and horse hides.
Loom – Loom drying consists in laying the hide above a reticular panel, fixing it with tongs and placing it in a big tunnel oven with a temperature of 60 degrees, from which after four hours the hide comes out dried. Tongs are also called rivets, for that reason a hide dyed and dried in that way can be also called "hide out of rivets".
Measuring – This operation can be performed both on finished and crust leather, its aim is to determine the dimension, the surface extension, the “measurement” of a hide. Once the unit of measurement was the square foot, but following the compulsory introduction of the metric system in all EU countries, it has been substituted by the square meter.
Nubuck – Nubuck is a type of not finished leather, used in the production of shoes, clothes and furnishing: it is obtained from chrome tanned veal skins. Nabuk leather is distinguished by its elegance through the silky effect given it by the superficial grinding.
Nappa leather – Very smooth and light leather obtained from bovine hides especially suited for women’s shoes and boots or for clothes
Paddle wheel – It is a machine, generally made of wood, with a cylindrical shape and with an internal whirl half submerged, which moves the liquid and the skins in it. This machine was used for the operations of resoaking and liming. Today its use is strongly in decline, due to the large quantity of water necessary.
Paint – For paint we mean leather (or crust), in general bovine, chrome tanned and finished with shiny polyurethane black, white or coloured paint,.
The most important technical requirements of the layer of paint are adhesion and resistance to bending.
Pickling – It is a sulphuric acid solution added to salt (sodium chloride) which avoids the swelling of the limed leather. The goal of pickling is to facilitate and regulate the chrome penetration in the leather.
Pressing – The skin, after soaking during tanning, is completely full of water. Pressing means squeezing the hide between two felt rollers to bring the hide to an optimal humidity level.
Printing – It means printing on the hide a particular design more or less in relief, in order to enhance the grain characteristics or to make some copies. It is done using hydraulic forging presses in which the hide is strongly compressed between two heated metallic plates. In order to print smaller types of grain, it is now common to use cylinder presses giving a continuous printing and a big saving of time.
Pull-up – Special article of greased leather with smooth grain, with a gloomy effect which becomes evident pulling the hide.
Re-tanning – When in ancient times tanning was done in ground holes, the heavy sole hides went through another tanning process, called re-tanning. Nowadays it has a different meaning, as it is the drum process which gives the hides particular smoothness and thickness features.
Refleshing – It is useful to clean the flesh side from remaining fat and shreds. This operation is effected with automatic machines which, using cylinders with helical blades, remove materials on the flesh side.
Regenerated – This is a type of an artificial leather obtained from the carniccio remaining after chrome or vegetal tanning. It is therefore a succedaneous of leather, made of dermal fibres glued together with synthetic resin. It is used mainly for the inside of suitcases, shoes, and for less relevant details. In fact it has very different features from natural leather, for example it does not breathe
Resoaking – It is the operation of re-hydration. It is the putting in soak of the raw salted hides, with the addition of chemical products, to bring back the fresh conditions in which they were found after flaying.
Sauvage – It is a bovine leather, dyed in pure aniline through a particular process with a stained effect.
Selection – It consists in selecting the hides after the tanning in function of their imperfections. It is a delicate phase entrusted to workers of proved experience. A selection can also be made on the finished hides in the phase of final control: in that case selection is effected for varying natural defects or for process defects, the goods then being divided in 2 or at maximum in 3 grades with different prices.
Sex – It is important to know the gender of the bovine before acquiring them, because it has an influence on the size, the shape and the fibre of the hides.
Shammy leather – It defines the chrome tanned split, greased and fluffed. It is a smooth, flexible, elastic leather with a woolly and velvet fibre, light or heavy, dried in fashion colourings. It is used for shoe-uppers, for clothing and sometimes for handbags. When the surface is silky, with a plushy down we define it as writing shammy leather.
Shaving – Shaving, effected by using cylinders with helical blades, is used to bring the hide to a homogenous condition, removing materials on the flesh side. Rejects, better known as shred of flesh from shaving in order to distinguish it from the shred of flesh from fleshing, are used as raw material for the production of the so-called regenerated leather.
Shoe-upper – For upper we define the superior and external part of the shoe which covers the foot but not his plant which supports the arch support and on the sole. Shoe-upper leather is obtained from cows, veal, goats, mainly chrome tanned, rarely vegetable tanned. It has to be a smooth & flexible, resistant above all to torsion.
Skin – Membranous tissue which covers animal bodies. All vertebrates, mammalians, birds, reptiles, fish, give suitable skins to be transformed in leather, but the hides which are most often used for tanning are the bovine, the ovine, the horse and the reptile ones. The microscope exam identifies 3 layers of skin: epidermis, derma and the subcutaneous adipose tissue. The epidermis is composed mainly of cheratin, it is the external part and it is composed of epithelial cells: this part is not transformed in leather, but destroyed along with the other constituents of the epidermis tissue (follicles, hairs, glands) during the phases of the process. Derma is the layer which is effectively transformed in leather. It is separated from the epidermis by a thin membrane which is effectively the grain; the most consistent part is composed of collagen. The adipose tissue is the layer which adheres to the animal's body and it is composed of elastic fibres and fat substances; also this too is destroyed with machines and chemical products.
Split – This is the remaining part of the hide after the "splitting”, that is the separation of the hide in the grain and the flesh sides: the split is the less valuable inferior layer of the derma.
Splitting – This is an operation which consists in dividing in two or more parts the hide section: we have the full grain (the most valued part) and the split (less valued part due to its inferior firmness). From hides with considerable substance, it is possible to obtain a third layer, less firm than the two called subsplit.
Staking – Is a process to soften the leather, a dry-effect process with a special machine (staking machine) which separates the fibres which remain stuck together during the tanning process.
Subsplit - see Splitting
Tanning – The goals of this operation are the irreversible stabilisation of the hide's fibre, which would otherwise decompose, and the improvement of the resistance characteristics. It is carried out in big drums with chrome liquids or aldehydes (mineral tanning), or with synthetic tannins (vegetable tanning).
Trimming – This is the operation after finishing, when there is the selection of the finished leather; it consists in cutting along the perimeter of the hides all the shreds and frays which can be created during the process. This scope of this operation is merely aesthetic.
Upholstery – In this way hides for sofas and armchairs are defined; once upon a time these were obtained from sheep and goats or veal processed in a certain way. Today for the same goal, big bovine hides are used almost exclusively.
Vacuum – It is a new drying system for chrome tanned hides; during the drying process a big depression is created above the hides laid above metallic plates heated at 50/60 degrees.
Waterproof – In this way we define upper shoe leather, strongly greased and resistant to water.
Weight-range – Hides are classified by weight. Usually, the bigger they are the heavier they are, so the weight-range gives also a first impression of the size.
Wet Blue – We define in that way hides in the wet status, which have passed a tanning process but are still without colours, greasing and finishing. They are humid and of a blue-green nuance, typical of tanning with chrome salts.
Wet White – So we define hides that, after liming, have had a light tanning process without chrome but with other synthetic products, principally aldehydes. They are humid and of a whitish colour.