Utilisateur:Dronama/Brouillon

{{Infobox Chimie | nom = Laccaic Acid | image = Paracetamol-skeletal.svg | image2 = Paracetamol-3D-vdW.png | taille image = 130 | légende = Représentations du paracétamol | DCI = ? | nomIUPAC = N-(4-hydroxyphényl)éthanamide | synonymes = acétaminophène | CAS = 103-90-2 | ECHA = 100.002.870 | EINECS = 203-157-5 | RTECS = VV2710000 | ATC = N02BE01 | DrugBank = ? | PubChem = 1983, 11321051, 10464506 | chEBI = ? | NrE = E100 | FEMA = 2006 | SMILES = CC(=O)NC1=CC=C(C=C1)O | InChI = 1/C8H9NO2/c1-6(10)9-7-2-4-8(11)5-3-7/h2-5,11H,1H3,(H,9,10)/f/h9H | InChIKey =

Laccaic acids are a group of five anthraquinone derivatives, from A to E, making the red shellac obtained from the Etymology : The word varnish goes back to the old Indian Sanskrit word laksha, meaning a hundred thousand lice, and came into German via the Italian “lacca” in the 16th century. The word also exists in Hindi (Lakh) and Sinhala (Lakda). The term Lac Dye comes from English "dye" means paint dye. This pigment is mostly found in South and South-East Asia, getting its name and area of use from there.


Usage : It’s primary used to dye natural fabrics (mostly silk, wool, or cotton) and food, whether it be drinks or solid products. It’s less used in cosmetics as carmine, is already the most used natural dye. The bright red colorant gave a lightfast tint to silk and wool. It is similar in colour to dyes obtained from cochineals and kermes. The colour of the dye can be modified by the choice of mordant from violet to red to brown. The use of lac dye can be traced back to 250 AD when it was mentioned by Claudius Aelianus, a Roman writer on a volume about natural history. This pigment made from lac dye, Indian Lake, was listed by Winsor & Newton in their 1896 catalogue.  


Derivatives : Laccaic acids are a group of five derivatives of anthraquinone, rated from A to E. These derivatives differ through one ramification except for the acid D, which is closer in form to the kermesic acid. These acids can all be represented in a general form (lac-dye), where the derivative A is the most important.