AT2 Silica Gel

Gel de Sílice AT2 is a thixotropic agent in amorphous silica powder that increases the viscosity of resins, gels and paints without affecting their cure. With an incorporation rate of just 3% by weight, it prevents materials from sagging on vertical surfaces and facilitates thin, controlled layer applications. In addition, due to its high absorption capacity, it acts as a matting agent in silicone-based paints and other formulations.

Technical specifications

What it is used for

Gel de Sílice AT2 is incorporated directly into the liquid phase of the material to modify its rheological behaviour. It is especially useful when you need a resin, paint or gel to stay where you apply it without sagging, and also when you want to reduce the surface gloss of the final finish.

• Gelling and thixotropisation of polyurethane resins for vertical surface or overhead applications
• Latex thickener for thick-layer applications without sagging
• Matting agent in silicone-based paints for hyper-realistic effects on prosthetics and figures
• Viscosity regulator in gel coats and top coats
• Flow control agent in formulations with metallic fillers or hollow glass microspheres
• Gloss reduction in casting resins where a satin or matte finish is desired

How to use it

1. Prepare your resin, gel or paint in the usual mixing container, without adding the catalyst or hardener yet if the system allows it.
2. Weigh the Gel de Sílice AT2: the recommended ratio is approximately 3% by weight of the total mix. For example, for 100 g of resin, add about 3 g of silica.
3. Incorporate the powder very slowly and with gentle movements. As it is extremely volatile, avoid pouring it all at once or in the presence of air currents.
4. Mix slowly and continuously until a completely homogeneous dispersion is achieved, with no lumps or unincorporated areas.
5. If the system requires a catalyst, add it at this point following the resin manufacturer's instructions.
6. Apply the thixotropised material with a spatula, brush or spray gun depending on the application, checking that it does not sag before proceeding with the entire piece.

Usage tips

Dose control to avoid overdoing it

An excess of Gel de Sílice AT2 can make the mix too thick and difficult to apply, or cause trapped micro-bubbles in the mass. Always start with 2–3% by weight and adjust in small increments (0.5% additional) if you need more body. In latex, the range can drop to 1–2% depending on the initial viscosity.

Lump-free incorporation

Fumed silica tends to form agglomerates when it comes into contact with liquids. To avoid this, sieve the powder over the resin while stirring constantly and use a spatula or wide-blade stirrer rather than a wire whisk. For large volumes, a low-speed mechanical stirrer ensures uniform dispersion without introducing air.

Use as a matting agent in silicone paints

When using AT2 as a matting agent in silicone paints for hyper-realistic effects, incorporate it into the base fraction before adding the pigments. This ensures better dispersion and prevents the pigments from interfering with its distribution. The use percentage in this case can be lower (0.5–1.5%) depending on the level of gloss you want to eliminate: the higher the dose, the more matte the finish.

Frequently asked questions