What it is

Lac is a natural resin of outstanding properties and exceptional versatility. The only known commercial resin of animal origin, it is hardened secretion of a tiny insect, Laccifer lacca (Kerr), popularly known as the lac insect. Lac being a natural organic resin having biodegradable properties is one of the many gifts of nature given to mankind. It has been in use for centuries in some form or other. Lately the scientific community has observed the significance of Lac resins.

Sticklac (Raw Lac)

Lac crop is collected by cutting down the lac bearing twigs of the hosts either weeks before larval emergence, when it is known as ari, or after, when it is known as phunki. Lac encrustations are separated from the twigs by either breaking off by hand or scrapping with a knife or sickle. Lac, thus gathered, is known as sticklac and it is in this form that cultivators bring it to the market for sale to manufacturers or their agents.

Properties of Lac

Lac, edible, is a hard amorphous natural resin & considered GRAS (Generally Recognized As Safe) by the FDA (Food and Drug Administration). The increasing use of the properties of lac has not been the result of chance. Alkyl esters of shellac in combination with cellulose nitrate and various synthetic resins make excellent resin-plasticizers for lacquers. On heat polymerization, the alkyl esters change into tough, flexible products possessing rubber-like properties. Aleuritic acid esters compounded with cellulose ethers and esters lend themselves excellently for the preparation of lacquers, plastics and fibre. Lac was employed as a dye in cosmetics and as as constituent of medicines for centuries. To-day lac is being used in many industries as a film former, a plastic, an insulator and an adhesive and cement.

Lac is used in Electrical equipments because of its excellent dielectric properties, dielectric strength, low thermal conductivity and a low coefficient of expansion. Shellac coatings do not change their electrical properties under UV-radiation.

Because of its acidic properties (resisting stomach acids), shellac-coated pills may be used for a timed enteric or colonic release. Shellac is used as a 'wax' coating on citrus fruit to prolong its shelf/storage life. It is also used to replace the natural wax of the apple, which is removed during the cleaning process. When used for this purpose, it has the food additive E number E904.

It is the central element of the traditional method of finishing furniture and fine violas, guitars and pianos. Because it is compatible with most other finishes, shellac is also used as a barrier or primer coat on wood to prevent the bleeding of resin or pigments into the final finish, or to prevent wood stain from blotching. Shellac is an odour and stain blocker and so is often used as the base of "solves all problems" primers. Lac provides an excellent barrier against water vapour penetration. Shellac-based primers are an effective sealant to control odours associated with fire damage.

Uses of Lac and its products

The largest uses for lac & its products are for the food, drug, and cosmetics industries. Fruits and vegetables in the produce aisle of your favorite grocery store are coated with lac 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 lac to make them slide easily down your throat, into your tummy. Of course the most important use of lac, in my not-so-humble opinion is as a woodworking finish, where you can make your projects shiny and eye-catching. Some of the major industrial and domestic fields in which it is used are listed below :

• As a film former : In french polishes, metal foil and pear varnishes, undercoats, enamels and wood sealers.

• In the cosmetic industry, shellac is known as a "Nail treatment" that lasts longer than regular polish. It is a combination of gel and regular polish and offers a water resistant seal among nail protection.

• As glaze for confectionery, coffee beans and medicinal pills.

• As aqueous varnishes for leather dressing, wood and paper and floor polishes, etc.

• As a dye for cotton and, especially, silk cloth.

• In watchmaking, due to its low melting temperature (about 80-100 °C), to adjust and adhere pallet stones to the pallet fork.

• In dental technology, where it is occasionally used in the production of custom impression trays and (partial) denture production.

• As a Ink : Applications such as lithographic ink, waterproof ink and colored ink.

• To increase the strength and longevity of ballet pointe shoes as a remedy for moisture weakening.

• In fireworks pyrotechnic compositions as a low-temperature fuel, where it allows the creation of pure 'greens' and 'blues'- colours difficult to achieve with other fuel mixes.

• As a plastic : In gramophone records, grinding wheels, sealing waxes, general moulded articles, insulators etc.

• As an insulator : In insulating varnishes, laminated paper products, micanites and micafolium, insulating cloth etc.

• As an adhesive and cement : In laminated paper and jute boards, plate sealer, gasket cement, general cements, optical cement, caping cement for electrical lamps and radio values, abrasive paper and cloth etc.

• As a Polish & Paints : Owing to the light color of bleached lac, bleached lac polishes are chiefly used for finishing wooden floors, playing cards, sports goods, ivory articles etc.

• As protective coatings : In confectionery and medicinal pills.

• As stiffening agents for felt and fabric hats : constituent of gossamer (or goss for short), a cheesecloth fabric coated in shellac and ammonia solution used in the shell of traditional silk top and riding hats.

• For preserving and imparting a shine to citrus fruits, such as lemons etc.

• In Jelly Belly jelly beans, in combination with beeswax to give them their final buff and polish.

• As a binder in Printing ink.

• As a protective and decorative coating for handlebar tape in cycle , and as a hard-drying adhesive for tubular cycle tires, particularly for track racing.

• For reattaching ink sacs when restoring fountain pens.

• For mounting insects, in the form of a gel adhesive mixture composed of 75% ethyl alcohol.

• As a binder in the fabrication of abrasive wheels, imparting flexibility and smoothness not found in vitrified (ceramic bond) wheels.

Areas of Cultivation

India contributes the largest share of world’s production of lac. Other countries producing lac are Thailand, Burma, Sri Lanka and Pakistan, Of these, the last three countries do no produce appreciable amounts. Thailand , however, has developed her lac industry considerably since World War II.

In India, the chief areas of lac cultivation are the districts of Chhattisgarh, adjacent districts of Madhya Pradesh, plateau of Bihar, West Bengal, Orissa and Assam. Limited quantity are also produced in Uttar Pradesh, East Punjab, Mysore and Madras.