Research and development


Quality improvement in production and the reduction of the CO2 footprint take priority for our research and development projects.

Use of cullet

  • Use of up to 20% cullet made of recycled glass in the flint glass furnace at the Köflach location
  • Use of industrial cullet (PIR glass)
  • 6% energy and 10% CO2 reduction


Use of secondary raw materials

  • 2015 – 2019 we increased the use of secondary raw materials from 5,000 tons per year to ~9,000 tons
  • Calumite/slag from steel production
  • Biomass ash
  • Soda ash


  • Does not contain fixed CO2 and thus significantly reduces the ecological footprint as well as the energy expenditure during melting
  • Blast furnace slag is available as a by-product of the steel industry
  • This homogeneous material has a positive effect on glass colour and quality


Biomass ash

  • The proprietary CAG Holding GmbH biomass plant produces over 10,000 tons of biomass ash which is available for us
  • Stoelzle participates in international research projects

State-of-the-art glass laboratory

  • Enlarged in-house glass laboratory
  • Experimental laboratory for research and development for the glass melt


Process optimization

  • The collection and analysis of process data enables a more precise calibration of the manufacturing processes
  • Implementation of new technologies in the field of inspection machines and process automatization

Type II pharmaceutical glass

  • New development of an old process
  • Innovative solution for interior surface treatment
  • Important reduction of the use of chemicals
  • Reduction of the environmental impact


NRG 4.0

  • New phosphorescent glass decoration technique
  • The colour changes according to the surrounding light