Mineral Technologies Mineral TechnologiesMinteqSpecialty Minerals
CareersCorporate ResponsibilityContact UsMSDSSitemapSearch
About SMIOur MineralsPaperSpecialty ApplicationsExhibitionsPublicationsUseful Links
 

In addition to the precipitated calcium carbonates (PCCs) widely used as the active ingredient in nutritional supplement and antacid tablets, and as an excipient, diluent or filler in other types of pharmaceutical and dietary tablets, Specialty Minerals Inc. (SMI) also manufactures USP talcs which can play a role in improved tablet making. 

Talc acts as both a glidant and lubricant during tableting, and as a polishing agent for tablet coatings. Talcs are chemically inert, oleophilic and hydrophobic, and have relatively high oil absorptions. Being the softest mineral, by definition as 1 on Moh’s scale of hardness, talcs have very low abrasion, protecting expensive tablet dies and other machine parts. 

Tablet Glidant and Lubricant
Glidants are added to the mixture to be pressed into tablets to improve the flowability of the powder or granulation. Poor flow through the feed system and into the tablet die can decrease productivity,and increase tablet making costs. Talcs added to powder blends improve flow rate, and decrease the angles of repose and fall.

Lubricants are added to the mixture to help keep the powder from sticking to the dies and other press parts during tablet manufacture, and to ease the ejection of the finished tablet from the press and reduce tablet breakage during ejection. Magnesium stearate is often used as a lubricant, but tends to increase disintegration and dissolution times. Replacing some of the magnesium stearate with a talc can maintain good lubricant activity while bringing disintegration and dissolution times back to acceptable levels.

While in some formulations, the largest particle sized talcs lead to the greatest improvement in powder flow, they usually result in mixtures that do not tablet well, or may not tablet at all. Talcs typically used as both lubricant and glidant are 2 to 3 micron fine talcs. SMI has two such talc products, MicroTalc® MP 15-38 USP talc, a 2.0 micron size and UltraTalc® 5000 USP talc, a 2.5 micron grade made in the U.S.

The SMI Healthcare Laboratory carried out a study of the glidant and lubricating properties of its USP talcs using products of particle sizes ranging from 2.5 to 16 microns made from two different talc ore sources. Glidant and lubricant performance of the range of talcs were tested in a spray dried lactose monohydrate-based formulation, and the lubricating properties of a small particle talc as a partial replacement for magnesium stearate in a dibasic calcium phosphate mix. This study confirms the advantages of using the fine USP talcs in tableting formulations. Click here to see the details and results of this study.


Chewing Gum Manufacture
Talc has two functions in chewing gum. With stick gums, talc is dusted onto the surface of the stick to absorb any oils or liquids that may migrate from the inside of the stick to the surface, which would cause the stick of gum to adhere to the wrapper. It’s that white powder you see on a stick of gum.

Additionally, it is also used inside the gum formulation when the gum flavor is a fruit. Normally, calcium carbonate is used in chewing gum as a masticating agent—a filler added to give it the right “chewiness.” But the flavor ingredients in fruit gums are acidic and would react with the calcium carbonate, giving off carbon dioxide gas, forming bubbles in the sticks and cracking the coverings on coated gum pieces. Inert talc, which does not react with acids, replaces the calcium carbonate as the masticating agent in these formulations.


Specialty Minerals Talcs For Foods, Nutritional Supplements and Pharmaceuticals
Two ranges of USP and food grade talcs are manufactured by SMI for healthcare applications.

The MicroTalc® MP USP talc series are six products ranging in size from 2 to 16 microns. They are made in the SMI Barretts, Montana plant, using platy microcrystalline Montana talc. The UltraTalc® USP talc series are also made in the U.S., using imported, usually Chinese, lamellar talc. While both are  platy, there are some morphological differences that may make one type or the other more suitable in your particular formulation. The SMI glidant and lubricant study (link below) gives an example of the differences.

All of these talcs are certified as USP, and are manufactured using Good Manufacturing Practices (GMP). They are also all certified as Kosher. Our talc manufacturing facilities are ISO 9000 quality certified.

 

Learn more: