Microcrystalline talc

Malusil Naintsch - absorbs interfering anionic substances without impairment of hydrophobic and organophilic character of material due to the activation process which changes its zeta potential Mistron Vapor C, P2, P5 - microcrystalline talc - compacted grades with 3% water)... 

Mistron 705, 754, Monomix, Super-20, Monomix-E, PE-60 - microcrystalline talc Naintsch E, SE, ASE, - extremely lamellar structure and talcs containing dolomite Luzenac OOC, 20M0, lOMO, Steabright, Steaopac - various finishes in decorative and industrial paints... 

Geologically, talc is typically formed by the alteration of a dolomite or serpentin-ite host rock. The talc formed from a dolomite host is typical of the type found in Montana, France, and China. These massive deposits are characterized by a microcrystalline talc structure, with talc concentrations in the deposit ranging from 93% to 99% talc by weight. Talc from these deposits can be sorted manually, optically, or mechanically to enhance color and talc content. 

Talc acts as a nucleating agent in crystalline polymers. It is not as effective as some chemical additives, but it does increase the crystallization temperature, as shown on the DSC chart (Fig. 8.18). The crystallization temperature of a polypropylene homopolymer is increased with talc concentration, as shown in Table 8.3. A very fine high-surface-area microcrystalline talc is usually used to increase crystallinity. The addition of talc to polypropylene, for any reason, will increase the crystallinity of the polymer. 

Other examples of the use of microcalorimetry to study drug-excipient compatibility in the solid state are provided by Selzer et al. (30), who studied the interaction between a solid drug and a range of excipients [including potato starch, a-lactose-monohydrate, microcrystalline cellulose (MCC), and talc] and Schmitt (31) who used water slurries instead of humidified samples. 

The third class of lubricant activity is the antiadherent. Some materials have adhesive properties and can adhere to the punch surfaces during compression. This will induce tablet disorders sticking, with a film forming on the surface of the tablets, or picking, where solid particles from the tablet stick to the punch surface. Most die wall lubricants also have antiadherent actions, and in many formulations, the addition of a specific antiadherent will not be required separately. The antiadherent includes talc, maize starch, and microcrystalline cellulose. 

Williams, R. 0.3rd, and McGinity, J. W. (1989), Compaction properties of microcrystalline cellulose and sodium sulfathiazole in combination with talc or magnesium stearate, /. Pharm. Sci., 78(12), 1025-1034. 

In another formulation for a water-dispersible tablet based on 74% crospovidone, containing as auxiliaries, microcrystalline cellulose, corn starch, silicon dioxide, talc etc. [615], it was possible to confirm that the compression force and... 

N-M20, Prever MIO, Extra 5/0 - high purity talc from Val Germanasca mine in Italy Mistrofil 325, 400 - microcrystalline chlorite... 

Drug formulations of dilitiazem hydrochloride also contain microcrystalline cellulose NF, sucrose stearate, eudragit, talc USP, magnesium stearate NF, hydroxy-propyl methyl cellulose USP, titanium dioxide USP, polysorbate NF, gelatin USP, etc. 

Most die-wall lubricants have antiadherent actions, and in many formulations, the addition of a specific antiadherent will not be required. Materials that can be added include talc, maize starch and microcrystalline cellulose. 

Distarch phosphate Fuller s earth Mica Microcrystalline cellulose Ozokerite Petrolatum Polyethylene, low-density Silica Talc Titanium dioxide... 

Beeswax Calcium hydroxide Calcium sulfate dihydrate Cocoa (Theobroma cacao) butter Corn (Zea mays) starch Distarch phosphate Lactose Lanolin Microcrystalline cellulose Petrolatum Starch Sucrose oleate Sucrose tristearate Talc Vegetable oil... 

Trideceth-14 Trideceth-15 stabilizer, tablets Microcrystalline cellulose stabilizer, talc... 

The importance of using sphere-forming excipients was noted early on. Conine and Hadley dted the necessity of using microcrystalline cellulose (4). Reynolds went on to indicate the need for either adhesive or capillary type binders (5). He dted cellulose gums, natural gums, and synthetic polymers as adhesives and microcrystalline cellulose, talc, and kaolin as capillary type binders. Since then much work has been conducted in an attempt to understand the significance of material properties. Some of the studies are discussed in the following text. 

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