Various binder components, and binder systems incorporating combinations of binder components, are known in the toothpaste art. Different binder components impart different rheological properties to the toothpaste. Cellulose polymers, in particular carboxymethyl cellulose (CMC), are widely used in toothpastes to act as a binder and thickener. However, for some toothpaste formulations, in particular toothpaste formulations containing a significant proportion of calcium carbonate particles, the addition of such a cellulose polymer can cause the toothpaste to exhibit a “stringy” effect and to exhibit “tailing” when the toothpaste is being manufactured. Such a stringy effect and tailing are manifested, for example, when the paste is mixed using a mixing blade and, after the blade has been lifted from the a mixer tank, paste on the blade falls downwardly under gravity as “tails” rather than being bound to the blade as a single non-flowing paste body.
There is a problem to fill the toothpaste package effectively and reliably if the toothpaste exhibits the stringy effect and tailing, particularly for toothpaste formulations containing a significant proportion of calcium carbonate particles.
There is accordingly a need in the art for a toothpaste composition which contains calcium carbonate particles and exhibits good rheological properties, in particular reduced stringiness and reduced tailing.
In addition, the binder component in the toothpaste has a significant impact on the stripe quality of the extruded strip to form a stable extrudable paste including the abrasive particles and the liquid phase. In striped toothpaste formulations containing a significant proportion of calcium carbonate particles, it is known to use a binder system which controls the stripe quality. In particular, is it is known to use a binder system incorporating the combination of carboxymethyl cellulose (CMC) and magnesium aluminium silicate (MAS) to provide a high stripe quality. However, the use of magnesium aluminium silicate (MAS) suffers from the problem that currently there are only a few qualified suppliers of toothpaste-grade magnesium aluminium silicate (MAS), which increases the cost and complexity of the supply chain.
There is accordingly a need in the art for a striped toothpaste composition which exhibits high stripe quality but avoids the supply chain problems of the known binder system incorporating the combination of carboxymethyl cellulose (CMC) and magnesium aluminium silicate (MAS).