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Ciao Fabrizio,
ti disturbo per una curiosità: se non ho tradotto male da wikipedia, per ricavare la cera shellac occorre un trattamento che può uccidere gli insetti che la producono. Come mai sul biodizionario le voci 'shellac' e 'shellac wax' sono segnate doppio pallino verde?
Grazie mille e scusa se rompo sempre...
:-)

Ciao rossi,
io non ho mai saputo questa cosa e a me francamente non risulta. Quindi mi informerò ed eventualmente cambierò, ma mica di tanto, il giudizio del biodizionario.

Grazie Fabrizio! Ti copio-incollo qui sotto il brano in questione, non fosse mai che ho tradotto sbagliato
;-)

"Shellac is a brittle or flaky secretion of the lac insect Kerria lacca, found in the forests of Assam and Thailand. Freed from wood it is called "seedlac".

Once it was commonly believed that shellac was a resin obtained from the wings of an insect (order Hemiptera) found in India. In actuality, shellac is obtained from the secretion of the female insect, harvested from the bark of the trees where she deposits it to provide a sticky hold on the trunk. There is a risk that the harvesting process can scoop the insect up along with the secretion, leading to its death. The natural coloration of lac residue is greatly influenced by the sap consumed by the lac insect and the season of the harvest. Generally in the trade of seedlac there are two distinct colors; the orange Bysacki and the blonde Kushmi.

When purified, the chemical takes the form of golden yellow/ golden brown flakes, this possibly providing the basis for the "Wing Source Story." Shellac is a natural polymer and is chemically similar to synthetic polymers, thus it is considered a natural plastic. It can be turned into a moulding compound when mixed with woodflour and moulded under heat and pressure methods, so it is classified as thermoplastic. But old mouldings tend to become thermoset, that is, they suffer chemical reactions over time and are no longer fusible".

Ciao rossi,
da quello che si può intuire la lacca può essere raccolta spntaneamente oppure coltivata. Solo nell'ultimo caso si devono uccidere gli insetti.
Il giudizio del biodizionario, comedetto, non cambia.

Ok, grazie!