Formulation Considerations

Choosing A Cleaning Silica Formulators choose a cleaning silica system to meet the desired toothpaste performance. Generally, performance is targeted to specific Pellicle Cleaning Ratio (PCR) and Relative Dentin Abrasion (RDA) ranges. The PCR of Huber cleaning silicas is displayed in the table shown to the right. This will drive a choice of standard cleaning, high cleaning silica or both. RDA values tend to increase with greater PCR. The absolute concentration of all cleaning silicas is important to achieve PCR/RDA targets and desired mouth-feel. (Often higher silica concentrations lead to better mouth-feel.) Zeodent® 103 high cleaning silica can be used alone or as a “booster” in conjunction with other Huber standard cleaning silicas to target higher cleaning/whitening performance. For maximum cleaning, it can be used at 10 to 20 percent loadings (higher, but acceptable RDA levels) with thickener silica to improve the mouth-feel. For lower RDA targets, Zeodent® 113 at ~20 percent loading or Zeodent® 124 at ~10 percent loading are usually better cleaning silica choices because of the higher loading level. These help reduce the level of gum necessary to obtain an acceptable rheological profile for toothpaste. Clear gel toothpaste is a special case where the optical properties of the silica must be taken into consideration along with meeting the PCR/RDA targets. Zeodent 113 and Zeodent 124 cleaning silicas deliver greater optical clarity than Zeodent 103 high cleaning silica.

• Choose a level of cleaning performance based on target PRC and RDA values

• Abrasion (RDA) typically increases with higher cleaning (PCR)

• Mouth-feel improves with higher loading levels