Gomme laque ...

Bonsoir,

Quelque'un saurait la diff?rence entre les flocons de gomme laque fabriqu? ? la main VS ? la machine ?

Merci ....

Ce que je sais est que le traitement et le raffinage peuvent se faire avec des moyens artisanaux plus ou moins m?canis?s mais je n'ai jamais entendu dire que ?a donnait des produits diff?rents.

Peux-tu nous en dire plus, tu m'intrigues.

Bonjour,

Je vous site ce que j'ai trouv? .. c'Est en anglais mais bon ...

[quote:e883ef0389]Hand Made Shellac

Hand Made Shellac Shellac is filled into a long, narrow cloth bag. One end of the bag is held in front of the charcoal oven while the other end attached to a windlass is gradually turned. The molten lac is scraped out and mixed thoroughly to ensure uniformity and transferred to a block of molten lac on the surface of a smooth porcelain cylinder filled with hot water.

Standing in front of fire, the workman so manipulates the sheet as to heat it uniformly and then scratches it with his hands, legs and mouth. It is pulled in all directions to produce a sheet of about5'x4' with a varying thickness from 1/16" at edges to about 1/1000 of an inch in the center. [/quote:e883ef0389]


[quote:e883ef0389]Machine Made Shellac
Machine Made Shellac Machine Made Shellac is produced in two different ways-Heat process and Solvent process.

Heat Process
Separation of pure lac is achieved by melting shellac by steam heat and squeezing the soft molten lac through filter by means of hydraulic presses. The molten lac is then stretched by means of rollers into long and continuous sheets which is broken into pieces to form the machine-made shellac under heat process.

Grades of heat process Shellac (Machine made)

* RUCHI Orange
* RUCHI TN
* RUCHI Lemon 1
* RUCHI Black TN
* RUCHI Black TN



Solvent Process
The separation of insoluble impurities is achieved by dissolving the lac in a suitable solvent, usually industrial alcohol, the solution is then filtered through fine cloth and the alcohol is recovered by boiling the solution. The molten shellac is then stretched to the required thickness on a roller followed by stretching machines. The solvent process lends itself to manufacture of different type of shellac containing varying percentage of shellac wax. Dewaxed or partly dewaxed shellac may be manufactured by this process. The wax content may be as low as 0.2%.

Grades of dewaxed Shellac

* RUCHI Orange
* RUCHI Lemon
* RUCHI Garnet
* Blonde
* Super Blonde
* Bleached Shellac
* Aleuritic Acid

[/quote:e883ef0389]

Voila ...

Je me demandais au niveau de l'utilisation si il y avait une grande diff?rence et quelles ?taient ces diff?rences ...

J'ai une autre question ...

Quelqu'un connait la diff?rence entre SHellac et Seedlac ?

C'est simplement une qualit? de gomme lacque (shellac), mais attention, quand je dis qualit? ?a ne veut pas dire plus ou moins bon mais de couleur diff?rente, et plus ou moins raffin?e. Le seedlac et le buttonlac sont 2 gommes lacques un peu plus brunes que la gomme lacque orange, et un peu moins raffin?es aussi.

D'apr?s ce que je sais, le seedlac r?sulte du premier traitement des brindilles recouvertes de r?sine. C'est un mat?riel qui contient encore des impuret?s comme des morceaux de branches et d'insectes.