12-6+The+Issue+Of+Shellac




 * WHAT IS SHELLAC?**

Shellac is a resinous compound secreted by the female lac bug (also known as: kerria lacca, laccifer lacca, carteria lacca and tachardia lacca) to form its cocoon. Resin is a polymer. There many kinds of resin and it is classified based on the functions. Shellac is used as a coating on medicines and candies. Shellac ranges in color from very light blond to ve

ry dark brown, with all shades of brown and yellow and orange and red in between. The color is influenced by the sap of the tree the lac bug is living on, as well as the time of harvest.Because it is contains crushed insects, another name for shellac is beetlejuice. However, because of the negative connotation associated with these names, on drug and nutritional supplement (vitamin) product labeling, shellac may be generically referred to as either enteric coating, pharmaceutical glaze, confectioner's glaze, resinous glaze, pure food glaze or natural glaze. In the European Union, shellac is known by the E Number E904.

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 * HOW IS IT MADE?**

 Shellac is scraped from the bark of the trees where the female lac bug deposits it to provide a sticky hold on the trunk. In the process of harvesting shellac, the insect may be crushed into the shellac resin. Raw shellac, which contains bark shavings and lac bug parts, is heated over a fire causing it to liquify. The thick sticky shellac is then dried into flat sheets, broken up into flakes, bagged and sold. Flakes are dissolved in denatured alcohol to make liquid shellac. It takes about 100,000 lac bugs to make 1 lb. of shellac flakes.

India is the principal lac producing country of the world, producing approximately 18,000 metric tonnes of unrefined (raw ) lac annually. About 85% of the country's production is exported to various countries. The USA, Germany and Egypt are some of the major lac importing countries of the world.


 * IN WHAT PRODUCTS IS THIS INGREDIENT FOUND?**

Although commonly thought of as a wood stain and protectant, shellac is also used as a glazing agent on pills and candies. Glazing agents are food additives that provide a shiny appearance and protective coating to foods guarding against unwanted changes to color, smell, or appearance. Skittles® candies sold in the UK (United Kingdom) contain shellac as a glazing agent. [Skittles® sold in the U.S. do not contain shellac, but do contain gelatin. In both countries, certain flavors contain the red food coloring cochineal (carmine, E120), derived from the crushed shells of the insect of the same name.] Shellac is sometimes used to replace the natural wax on apples which is removed during the cleaning proc ess. In the pharmaceutical industry, shellac is used as an enteric coating on time-release medications, allowing the medicine to be absorbed in the intestinal tract, instead of in the stomach. It is used on safety coated aspirin products to prevent stomach irritation. **FUNCTIONS OF SHELLAC IN INDUSTRIES?** The largest uses for shellac are for the food, drug, and cosmetics industries. Fruits and vegetables in the produce aisle of your favorite grocery store are coated with shellac and wax to make them shiny and eye-catching. In the world of cosmetics, women (and men) use shellac-based hair-spray to make themselves appear shiny and more eye-catching. Many vitamins, pills and food supplements are coated with shellac to make them slide easily down your throat, into your tummy. The most important use of shellac is for Woodworking finish, it can make the pro jects shiny and eye-catching.
 * COMPOSITIONS OF SHELLAC**

Shellac/Lac has been found to be composed of the following constituents: Lac Dye (a mixture of anthroquinoid derivatives) || 1-2 % ||
 * CONSTITUENT || PROPORTION ||
 * Lac Resin (a polyester complex of straight-chain hydroxy fatty acids and sesquiterpenic acids) || 68 % ||
 * Lac Wax (a mixture of higher alcohols, acids and their esters) || 6 % ||
 * Others (insect debris, impurities etc.) || 25 % ||




 * APPLICATIONS OF SHELLAC**

The various applications of Shellac/Lac can be summarized as follows:


 * LAC RESIN**

v Food processing industry v Cosmetics and toiletries industry v Varnish and printing industry v Coating of fruits and ve

getables v Electrical industry v Leather industry v Adhesive industry v Pharmaceutical industry v Perfumery industry v Miscellaneous applications


 * LAC DYE**

v Food and beverages industry v Textile industry


 * LAC WAX**

v Polishes (shoe, floor, car polishes etc.) v Food, confectionery

and tablet finishing


 * ADVANTAGES**

1. Non-yellowing when compared to varnish and cellulose-nitrate based lacquers.

2. Quick-drying. Many shellacked items can used the same day or shortly thereafter.

3. Wide variety of colors available.

4. Superior adhesion.

5. Excellent hardness -- it can be sanded and rubbed out well.

6. Excellent as a sealer coat to raise the fibers of the wood for subsequent sanding. Also seals in finishing contaminants such as silicone, waxes, dirt and oils.

7. Ease of repair. Because shellac re-dissolves in alcohol, scratches and other minor surface imperfections can be invisibly repaired by re-applying shellac to the damaged area. The new shellac melts into the old shellac allowing for perfect repair work.

8. Ease of removal. Old and new shellac can be removed with denatured alcohol which eliminates the need for harmful and toxic strippers.

9. Can be wiped on (padded), brushed or sprayed -- all with good results.

10. FDA approved -- safe for food utensils and children toys.

11. No unpleasant or toxic fumes.


 * DISADVANTAGES**

1. It re-dissolves in alcohol so perfumes and strong alcoholic beverages like whiskey will mar the surface.

2. Forms white rings on contact with water. This is more of a problem with shellacs that have wax and old shellac surfaces.

3. Tendency to show scratches. The resistance to scratches can be improved by a simple waxing.

4. Has a shelf life after mixed in alcohol.

5. Not resistant to alkaline compounds. Alkaline chemicals such as lye and ammonia discolors and mars shellac because of its acidic composition. These chemicals are frequently found in household cleaning products.

6. Sensitivity to heat -- shellac starts to soften at about 150 degrees F. Hot items can mar the surface

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