talc

Talc is the world’s softest mineral. Although all talc ores are soft, platy, water repellent and chemically inert, no

two talc ores are quite the same. Talc is a vital part of everyday life. The magazines we read, the polymers in our

cars and houses, the paints we use and the tiles we walk on are just some of the products that talc enhances.

Talc is a hydrated magnesium sheet silicate. The elementary sheet is composed of a layer of magnesiumoxygen/

hydroxyl octahedra, sandwiched between two layers of silicon oxygen tetrahedra. The main or basal

surfaces of this elementary sheet do not contain hydroxyl groups or active ions, which explains talc’s

hydrophobicity and inertness.

 

APPLICATION OF TALC : Agriculture And Food

Talc is an effective anti-caking agent, dispersing agent and die lubricant and therefore helps animal feed and

fertilizer plants to function more efficiently. In premixes and agricultural chemicals, it makes an ideal inert

carrier. Talc also is used as an anti-stick coating agent in a number of popular foods including chewing gum,

boiled sweets, cured meats, and for rice polishing. In olive oil production, as a processing aid, it increases yield

and improves the clarity of the oil.

Paints

Owing to its low cost and platy structure, Talc is widely used in the paint industry, particularly in marine paints

and protective coatings. Benefits include:Reinforcement of the Paint film,Reduction in the quantity of primary

pigment consumed, Controls gloss of paints,Helps in suspending other pigments, Improves durability of

Paint, Improves rust inhibitive properties & corrosion resistance, Improves stability of emulsion paints,

Prevents enamel from running, In traffic paints for better abrasion resistance, Improves stain resistance in

Paint, Enhancement of smoothness at the time of application. The amount of Talc used in paints varies

between 2 to 30%. Also the fineness of Talc used in paints varies between 100Âμ to 20Âμ. The oil absorption of

TALC used in Paints is between 40 to 60 gm per 100 gm. PHARMACUTICALS: Its high purity and lamellarity

makes it a high performance component in the creation of pharmaceutical products.In pharmaceuticals, talc

is used primarily as a basis for powders. It is employed as an active agent and auxiliary agent, e.g. as a carrier

for pharmaceuticals with a disinfectant, astringent, anti-itching or cooling effect. Talc is also suitable as a

lubricant in pill manufacturing.

Plastics

With the plastic industry on a fast growth-track, the usage of talc is growing fast in PP, HDPE, LDPE, PVC, ABS &

Thermosetting Compounds.Talc is having a huge demand as a filler due to its following properties:Platy in

nature, Excellent blending characteristics with oleoresinous materials , Excellent thermal resistance, Superior

electrical resistance, Chemically inert, Smooth greasy feel, Improves Chemical & Heat Resistance, Improves

impact absorbing strength, Gives dimensional stability , Improves stiffness, hardness, tensile strength, Gives

electrical insulation property. In Polypropylene, talc is used to improve mechanical strength and scratch

resistance. The Automotive industry uses Talc for dashboards, interior trims, bumpers etc. Talc is also used in

plastics for computer bodies and garden furniture where increased UV resistance is a highly desirable

characteristic. It is also used as antiblocking agent in film-like bags used for fruits, vegetables etc. Many

compounding factories are also using Talc. Talc imparts the the following properties to plastic:

Talc is a phyllosilicate which imparts a wide range of functions to floor and wall tiles and sanitary ware,

tableware, Refractories and technical ceramics. In traditional building ceramics (tiles and sanitary ware), it is

used essentially as a flux, enabling firing temperatures and cycles to be reduced. In refractory applications,

chlorite-rich talc is transformed into cordierite to improve thermal shock resistance. For steatite ceramics, talc

with a microcrystalline are the most appropriate. During firing, the talc is transformed into enstatite, which

possesses electro-insulating properties. As for very low iron content talc, they are particularly suitable for use

in frit, engobe and glaze compositions. Paper Plastics The Plastic Industry uses Talc of 20Âμ to 1Âμ particle size.

Ceramics

Talc is a phyllosilicate which imparts a wide range of functions to floor and wall tiles and sanitary ware,

tableware, Refractories and technical ceramics. In traditional building ceramics (tiles and sanitary ware), it is

used essentially as a flux, enabling firing temperatures and cycles to be reduced. In refractory applications,

chlorite-rich talc is transformed into cordierite to improve thermal shock resistance. For steatite ceramics, talc

with a microcrystalline are the most appropriate. During firing, the talc is transformed into enstatite, which

possesses electro-insulating properties. As for very low iron content talc, they are particularly suitable for use

in frit, engobe and glaze compositions.

Coatings

Talc confers a whole range of benefits to coatings. In interior and exterior decorative paints, they act as

extenders to improve hiding power and titanium dioxide efficiency. Talc’s lamellar platelets make paint easier

to apply and improve cracking resistance and sagging. They also enhance matting. In anti-corrosion primers,

talc is used to improve corrosion resistance and paint adhesion. Talc also brings benefits to inks, jointing

compounds, putties and adhesives.


Paper

 Talc is used in both uncoated and coated rotogravure papers where it improves printability as well as reducing

surface friction, giving substantial improvements in productivity at the paper mill and print house. It also

improves mattness and reduce ink scuff in offset papers. Used as pitch control agents, talc “cleans” the paper

making process by adsorbing any sticky resinous particles in the pulp onto their platy surfaces, thereby

preventing the agglomeration and deposition of these on the felts and calendars. As opposed to chemical

pitch-control products that pollute the process water, talc is removed together with the pulp, enabling the

papermaker to operate more easily in closed-circuit. In specialty papers such as colored papers or labels, talc

helps to improve quality and productivity.