Veegum
Glaze Hardener, Binder
Links to Other Materials
- CMC Gum - Related
- Bentone MA - Related
- Bentonite - Related
- Cache
Miscellaneous
- Family: Additive
- Region: North America
- Mined At: Unspecified
- Raw Mineral: No
- Generic: No
Notes
Veegum is not a 'gum', rather it is a fine particle mineral called 'smectite' (bentonite and hectorite are similar minerals). It is a complex colloidal and extremely plastic magnesium aluminum silicate. It is an off-white insoluble flake magnesium aluminum silicate that swells to many times its original volume when added to water. Its aqueous dispersions are thus high viscosity thixotropic gels at low solids. Veegum is not subject to attack by microorganisms. Various grades are classified according to viscosity and ratio of aluminum to magnesium content.
Density (Mg/m3): 2.6
Viscosity (after shear mixing, 5% dispersion): 250 cps +/- 25%
Moisture: 8% max
Bacterial Count: less than 1000 per gram. No E. coli, S. aureus, Salmonella sp., P. aeruginosa at time of shipment.
It is very important to properly hydrate the powder, mix it in water before adding other ingredients (different grades of Veegum hydrate at different rates). Do not underestimate the time needed, in 25C water it could take 120 minutes using a propeller mixer! Using hot water or a higher energy mixer can drastically cut the time needed. It is also important to use the same water temperature, mixing time and energy and viscosity each time it is used to get consistent behavior in the slurry.
Veegum T is used as an in-mix suspending agent and surface hardener for glazes. It is also suitable for use as a spray-on surface hardener before decorating (mix it with water and put a light layer on dried ware).
VGT is employed as a plasticizing agent for nonplastic formulations such as high alumina or zirconia bodies, and as a nonmigrating binder in extruded bodies. The material is clean and therefore does not affect fired whiteness.
VGT has a high pH of 8.5 and yet acts as a flocculant, contributing to the workability of porcelain. 1.5-2.0% added to a porcelain, that is otherwise a little to short for modeling or throwing, will transform it into a plastic material.
Veegum CER is a mixture of Veegum T and medium viscosity sodium carboxymethylcellulose that gives optimum surface hardening of unfired ceramic glazes for safe handling of the ware. It serves as hardener, suspending agent and viscosity stabilizer in glazes.
Veegum Pro is Veegum treated with amine to improve dispersability. Veegum Pro hydrates readily in hot or cold water to form high viscosity dispersions. Recommended for use where a minimum amount of water is required and/or only slow type mixers are available.
Other Grades: F, HV, K, S728, HS
URLs
- Product Description - http://www.rtvanderbilt.com/veegum.pdf
- Carboxymethylcellulose information - http://www.lsbu.ac.uk/water/hycmc.html
- http://www.rtvanderbilt.com/VEEGUM+Presentation+Pt3.pdf - Powerpoint presentation on the use Veegum
Suppliers
- R.T. Vanderbilt
- Vanderbilt Minerals
Authors
- Tony Hansen (Owner)
XML
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<material name="Veegum" descrip="Glaze Hardener, Binder" generic="0" rawmineral="0" searchkey="Veegum T, Veegum CER, Veegum Pro" loi="0.00">
<families>
<family name="Additive"/>
</families>
<regions>
<region name="North America"/>
</regions>
<references>
<reference name="seealso" reason=""/>
<reference name="seealso" reason=""/>
<reference name="seealso" reason=""/>
</references>
<suppliers>
<supplier name="R.T. Vanderbilt" country="US" url="www.rtvanderbilt.com" label=""/>
<supplier name="Vanderbilt Minerals" country="US" url="http://www.rtvanderbilt.com/vmc.htm" label=""/>
</suppliers>
<notes>
<note>Veegum is not a \'gum\', rather it is a fine particle mineral called \'smectite\' (bentonite and hectorite are similar minerals). It is a complex colloidal and extremely plastic magnesium aluminum silicate. It is an off-white insoluble flake magnesium aluminum silicate that swells to many times its original volume when added to water. Its aqueous dispersions are thus high viscosity thixotropic gels at low solids. Veegum is not subject to attack by microorganisms. Various grades are classified according to viscosity and ratio of aluminum to magnesium content.
Density (Mg/m3): 2.6
Viscosity (after shear mixing, 5% dispersion): 250 cps +/- 25%
Moisture: 8% max
Bacterial Count: less than 1000 per gram. No E. coli, S. aureus, Salmonella sp., P. aeruginosa at time of shipment.
It is very important to properly hydrate the powder, mix it in water before adding other ingredients (different grades of Veegum hydrate at different rates). Do not underestimate the time needed, in 25C water it could take 120 minutes using a propeller mixer! Using hot water or a higher energy mixer can drastically cut the time needed. It is also important to use the same water temperature, mixing time and energy and viscosity each time it is used to get consistent behavior in the slurry.
Veegum T is used as an in-mix suspending agent and surface hardener for glazes. It is also suitable for use as a spray-on surface hardener before decorating (mix it with water and put a light layer on dried ware).
VGT is employed as a plasticizing agent for nonplastic formulations such as high alumina or zirconia bodies, and as a nonmigrating binder in extruded bodies. The material is clean and therefore does not affect fired whiteness.
VGT has a high pH of 8.5 and yet acts as a flocculant, contributing to the workability of porcelain. 1.5-2.0% added to a porcelain, that is otherwise a little to short for modeling or throwing, will transform it into a plastic material.
Veegum CER is a mixture of Veegum T and medium viscosity sodium carboxymethylcellulose that gives optimum surface hardening of unfired ceramic glazes for safe handling of the ware. It serves as hardener, suspending agent and viscosity stabilizer in glazes.
Veegum Pro is Veegum treated with amine to improve dispersability. Veegum Pro hydrates readily in hot or cold water to form high viscosity dispersions. Recommended for use where a minimum amount of water is required and/or only slow type mixers are available.
Other Grades: F, HV, K, S728, HS</note>
</notes>
</material>
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