March 26, 2024

TOLSA, a global supplier of specialised additives for the paints and coatings industry, reports strong growth for its portfolio of rheological additives based on high-purity sepiolite technology. The company’s long-term strategy is to expand its resources and capabilities with new investment in technology, manufacturing, capital, and personnel.

“With our versatile PANGEL S product offering we are firmly positioned as a strategic supplier to the US market,” said Alberto Fernández-Ibarburu, industrial product development leader for TOLSA. “We have tailored our products for water-based and solvent-based systems to meet the broad manufacturing needs of OEMs and producers, ensuring greater efficiencies and productivity.”

Powdered rheology additives are commonly used in paints and coatings to improve their rheological properties (pseudoplasticity/thixotropy), reducing the sagging effect, and enhancing workability. However, there are challenges associated with using these additives in terms of acquiring the required performance. The common challenges associated with these powdered rheology additives include:

Dispersion: There are issues related to the dispersion of mineral powdered rheology additives for paints and coatings formulations that may result in inconsistency and poor performance of the final product. It can lead to sedimentation issues with a lack of homogeneity in the mixture.

Leveling: Leveling refers to the ability of a paint or coating to flow out well and form a smooth surface after application. Paints and coatings need to possess the leveling properties that result in even surfacing. The aesthetics of the coated surface is determined by its leveling as it eliminates the surface defects occurring after the application. It is critical to obtain the right balance between sag resistance and leveling.

Application: Pseudoplastic behaviour of paints and coatings provides sedimentation and sag control, but at the same time good workability due to the viscosity reduction during the application. It is also needed during the application of a certain viscosity level to avoid spattering or dripping from the tools.

The rheological additives from the PANGEL S series are crafted with high-purity sepiolite. Due to the high pseudoplastic profile, PANGEL gives strong performance along with additional suspension capacity, and anti-sagging but at the same time excellent workability and application. PANGEL additives have been specially designed to optimise the rheology of the whole thickening systems either alone or in combination with other organic additives.

Sepiolite-based PANGEL S is a phyllosilicate with an acicular morphology that provides a strong chemical and thermal stable structure at high temperatures, at a wide pH range (3-14), and has very low electrolyte sensitivity. PANGEL S requires an appropriate particle wetting and subsequently a mechanical agitation that guarantees peripheral speeds between 18 and 25 m/s.

With PANGEL formulations, a mineral thickener is introduced and dispersed in a coating matrix to form a gel structure. When these silicate mineral particles are well dispersed, they interact among themselves and at the same time with other components of the paint. These interactions enable the formation of a gel structure which is mainly responsible for an increase in the viscosity and therefore provides sag and sedimentation resistance. These interactions are caused by a weak dipole attraction that could be easily broken under shear. Due to this fact, the coating viscosity decreases when the product is stirred, thus making it easier to work with.

A key feature of PANGEL technology is its ability to yield fewer defects when incorporated into a coatings system, thus providing a competitive advantage for the end-user. PANGEL products are characterised by the “3S” benefits they deliver: settling, sedimentation, and syneresis. They are particularly efficient in architectural and industrial coatings where solids content and filler density often drive strong variations in coatings stability.

PANGEL series products are sold as micronized solids. Their dispersion process is similar to that of other solid components of the formulation, ensuring an appropriate wetting of the product and application of sufficient mechanical energy (shear).

PANGEL S9, a purified sepiolite, is one of TOLSA’s leading products, offering high-shear thinning. It is normally used as a co-thickener with HEC or associative thickeners for improving syneresis and sedimentation and replaces attapulgite thickeners at half dosage.