The right glass for the respective purpose

Two glass types are mainly used for laboratory instruments made of glass

soda-lime glass and

borosilicate glass

They differ in terms of their chemical and physical properties and are therefore used for different applications.

Soda-lime glass

Soda-lime glass accounts for the majority of industrially manufactured glasses. It typically consists of 71 to 75 per cent sand (SiO2), 12 to 16 per cent natron (Na2O) and 10 to 15 per cent lime (CaO). Soda-lime glass is used for everyday items such as bottles for beverages, jars for food, drinking glasses and flat glass. The glasses have a smooth non-porous surface. In contrast to borosilicate glass, it is much more sensitive to temperature fluctuations. It is therefore not employed for applications involving severe changes in temperature.

Borosilicate glass

70 to 80 per cent of the weight of borosilicate glass consists of sand. Seven to 13 per cent are accounted for by boron trioxide, four to eight per cent by sodium oxide and potassium oxide and two to seven per cent by aluminium oxide. It has a higher chemical resistance than soda-lime glass and a higher resistance to heat and temperature changes. Borosilicate glass is for this reason also used for production plant components in the chemical industry, the laboratory and pharmaceutical industry or as glass for lamps. Examples of the use of borosilicate glass in the household include baking and pie dishes.

Borosilicate glass is used for measuring flasks, measuring cylinders and burettes, due to its high degree of strength. However, reagent bottles made of this material are also available in the Hirschmann laboratory glass range for appropriate application areas.

Hirschmann works exclusively together with selected quality suppliers. The following glass types are used for our glass volumetric measuring devices:

Measuring flasks: DURAN from Schott, borosilicate glass 3.3 in compliance with ISO 3585

Measuring cylinders: DURAN from Schott, borosilicate glass 3.3 in compliance with ISO 3585

Burettes: DURAN from Schott, borosilicate glass 3.3 in compliance with ISO 3585

Measuring pipettes: AR glass from Schott, soda-lime glass

Volumetric pipettes: