Leather Workmanship

The wet-blue leathers warehouse

The wet-blue leathers warehouse

The warehouse buys leathers which have already been subjected to the first tanning, and in the same warehouse the whole wet-blue leathers are divided halves and selected and chosen according to article, then levelled to the required thickness and finally sent to the tanks for re-tanning and dying.

The re-tanning and dying drums

The re-tanning and dying drums

The semi-raw material, which has already been given a first summary tanning, is levelled to reduce the leather to the required thickness and then degreased. Degreasing is carried out in a series of barrel-shaped containers, called “bottali”, in precious wood, arranged so that they can be turned on their axis; they are moved by a toothed wheel system which, with the movement of the bottali, ensures an effective detergent action.

The next step, still in the mechanically rotated bottali, is to reload the leather to complete the first summary tanning; this operation consists of adding tannins (natural and synthetic) with small quantities of trivalent chrome. After this, in order to make the leathers more flexible, lubricants of fibre origin are added to the bottali, such as oils, fatty substances, sulphates, etc. This is followed by dying; for this operation, with the leathers always in the bottali, suitable colorants are added to give a specific colour either to the surface of the leather or throughout the thickness.

Hanging in the wind or squeezing

Hanging in the wind or squeezing

After the leathers have been removed from the bottali, a mechanical operation is carried out, in an industrial mangle, which allows for a first reduction of the water content (squeezing operation).

Vacuum

Vacuum

After the leathers have been through the mangle, they are stretched out on heated steel surfaces, by which means and depending on the temperature and the time, the leathers are further dried.

Chain loading for air-drying

Chain loading for air-drying

After the previous step, which takes place in a vacuum, the leathers are then hung on a rotating carousel which runs along the whole of the upper part of the building, and the leathers are thus naturally dried in the air.

Aerial chain unloading

Aerial chain unloading

Once the leathers on the chain have dried, they are unloaded and placed on special trolleys.

Palissone

Palissone

Once the leathers have been unloaded from the aerial chain, they are then placed inside the palissone: here they can be spread out and softened, according to the setting of the machines and depending on the articles.

Laboratory for testing the finish

Laboratory for testing the finish

Before the leathers are finished, the finishing processes are tested in the laboratory; once the colour and other characteristics have been defined, they are then placed in special spray machines.

Spray-finish machines

Spray-finish machines

Once the effectiveness and the yield of the different types of paint have been tested in the laboratory, the leathers are then sprayed in a special plant composed of a row of rotating cabins, each with eight + eight pistols with double rotating ducts, which spread the paint or other solutions onto the leathers with a slow movement, transported by a conveyor belt and by a second line which is used for drying or damping the leathers.

Machine with precious stones for coating and painting

Machine with precious stones for coating and painting

Rolimacr machine for impregnating with oils and waxes

Rolimacr machine for impregnating with oils and waxes

Fulling drums for softening the leathers for nappe, nubuk or flared articles

Fulling drums for softening the leathers for nappe, nubuk or flared articles

Three-roller rotating machine

Three-roller rotating machine

This operation is carried out in order to give shine and the final “feel” to the leather, which is sent under hydraulic pressure through the heated rollers at an electronically controlled temperature; the time of contact is controlled by a timer.

Trimming

Trimming

Measuring

Measuring

Once in the final warehouse, the leathers are trimmed, selected, measured, packaged, and finally arranged on pallets for despatch.

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