Desiccant silicas

Indicating silica

Narrow-pore silica gels (Upasil 20) are also available with different color indicators. The degree of saturation is visualized by a change in color.

Different to the past (when indicators based on cobalt chloride have been used), present indicators are environmentally safe and available in a wide range of colors. Upasil indicating silica can be regenerated by heating, thus changing the color back to the active state. This allows the products to be used alone or in combination with, i.e. molecular sieves in gaugeglasses. This allows a simple visual inspection of the adsorption degree.

As with the narrow-pored white silicas, a maximum water adsorption of approx. 35% of the silicas‘ weight can be achieved.

Our product range

Upasil® ruby
Upasil® ruby

Upasil® ruby is an indicator silica gel used wherever products need to be reliably protected from moisture. The degree of saturation of the silica gel is indicated by a distinct colour change from ruby red to orange-yellow.

The product is available in spherical form in sizes 1–3 mm and 3–6 mm. The pH of the indicator gel ranges from 3.5 to 7.

Upasil® ruby contains a mixture of various indicators, is free from hazardous substances and therefore does not need to be classified as dangerous goods.

Upasil® 20 yellow
Upasil® 20 yellow

Upasil® 20 yellow is an indicator silica gel that provides reliable protection against moisture. The degree of saturation is indicated by a clear colour change from yellow to light blue.

The product is available in crushed form with a particle size of 2.5–6 mm or in spherical form with a diameter of 2–5 mm. The pH of the indicator gel is between 3.5 and 7.

Upasil® 20 yellow contains a mixture of various indicators; it is free from hazardous substances and is therefore not classified as a dangerous good.

Upasil® 20 blue cf
Upasil® 20 blue cf

Upasil® 20 blue cf is an indicator silica gel that provides reliable protection against moisture. The degree of saturation is indicated by a distinct colour change from blue to pink.

The product is available in spherical form with a particle size of 2–4 mm. The pH of the indicator gel is between 4 and 8.

Upasil® 20 blue cf contains a mixture of various indicators; it is free from cobalt(II) chloride and is therefore not classified as a dangerous good.

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