Our paper aims to investigate both preparation and use of colour in Mediterranean area in two different historical periods: Late Helladic and Late Archaic and a modern technique of extraction from vegetable sources. We don’t have any historical-literary source about these items, so that it is necessary to take notice of more informative elements.In Mycaenean world we can find data in epigraphic documents about clothes and leather colouring. We will consider some tablets to understand, by a philological analysis, modalities and materials used for this kind of colouring process. About Late Archaic period (540-480 b.C.), we will concentrate our attention on Etruscan world. We will match results of chemical and physical analyses on pottery decorations, funeral paints and terracotta decorations with historical-archeological evidences lately acquired, in order to outline a description of materials used to create colours in different above mentioned painting contexts, and to single out provenience areas of these materials. Till now, this kind of data has not been object of a peculiar and complete investigation. Technique of extraction In this paper, we carried out a review about solid-liquid extractive techniques and we described an innovative solid-liquid extraction technology, Naviglio Extractor, that is based on a new extractive principle: Naviglio's Principle. We applied this technology to the extraction of tannic substances from chestnut wood. This extractive process changes completely the philosophy of the solid-liquid extraction thanks to the discovery of a new principle of extraction: the Naviglio's Principle. The extraction happens for the generation of a negative gradient pressure from the inside toward the outside of the solid matrix therefore it can be conducted at room temperature or sub room temperature. An extractive cycle is constituted by a static phase and a dynamic one; during the static phase the liquid is put under pressure to about 6-8 atm on the solid to extract and it is left for sufficient time to allow the liquid to penetrate the inner of solid and to balance the pressure between the inside and the outside of it. After this time, the pressure is immediately removed the falls quickly to 0-1 atm. We have extracted Kg 1 of chestnut wood using l 2 of water as solvent. Finally the volume of the water is reduced to l 1. The extraction is performed through 4 steps: each step is constituted by an extraction of g 242 of chestnut wood using l 2 of water. The same l 2 of water are used for the next extraction of g 242 of chestnut wood. We have checked step to step the concentration of polyphenols using Folin-Ciocalteau reagent: final polyphenol concentration is 4.6g/L.
COLOUR AND LEATHER TREATMENT IN MEDITERRANEAN AREA NOW AND IN ANCIENT TIMES: SOME MYCAENEAN AND ETRUSCAN EVIDENCES AND NEW TECHNIQUES OF EXTRACTION LINKED TO TRADITIONAL METHODS
montesano domenico;
2002
Abstract
Our paper aims to investigate both preparation and use of colour in Mediterranean area in two different historical periods: Late Helladic and Late Archaic and a modern technique of extraction from vegetable sources. We don’t have any historical-literary source about these items, so that it is necessary to take notice of more informative elements.In Mycaenean world we can find data in epigraphic documents about clothes and leather colouring. We will consider some tablets to understand, by a philological analysis, modalities and materials used for this kind of colouring process. About Late Archaic period (540-480 b.C.), we will concentrate our attention on Etruscan world. We will match results of chemical and physical analyses on pottery decorations, funeral paints and terracotta decorations with historical-archeological evidences lately acquired, in order to outline a description of materials used to create colours in different above mentioned painting contexts, and to single out provenience areas of these materials. Till now, this kind of data has not been object of a peculiar and complete investigation. Technique of extraction In this paper, we carried out a review about solid-liquid extractive techniques and we described an innovative solid-liquid extraction technology, Naviglio Extractor, that is based on a new extractive principle: Naviglio's Principle. We applied this technology to the extraction of tannic substances from chestnut wood. This extractive process changes completely the philosophy of the solid-liquid extraction thanks to the discovery of a new principle of extraction: the Naviglio's Principle. The extraction happens for the generation of a negative gradient pressure from the inside toward the outside of the solid matrix therefore it can be conducted at room temperature or sub room temperature. An extractive cycle is constituted by a static phase and a dynamic one; during the static phase the liquid is put under pressure to about 6-8 atm on the solid to extract and it is left for sufficient time to allow the liquid to penetrate the inner of solid and to balance the pressure between the inside and the outside of it. After this time, the pressure is immediately removed the falls quickly to 0-1 atm. We have extracted Kg 1 of chestnut wood using l 2 of water as solvent. Finally the volume of the water is reduced to l 1. The extraction is performed through 4 steps: each step is constituted by an extraction of g 242 of chestnut wood using l 2 of water. The same l 2 of water are used for the next extraction of g 242 of chestnut wood. We have checked step to step the concentration of polyphenols using Folin-Ciocalteau reagent: final polyphenol concentration is 4.6g/L.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
