- 3M Specialty Products
- Airgas
- Alex C. Fergusson Inc.
- Ashta Chemicals
- Avatar
- BASF
- BP Chemical
- Cargill Salt
- Carmeuse Lime
- Chemco
- Cytec
- Degussa Corporation
- Delta Chemical Corporation
- Dema Engineering
- Eagle Picher Minerals Inc.
- General Chemical
- Greer Lime
- Honeywell
- Houghton Chemical
- Hydro-Kirby Agri Services
- Jungbunzlauer
- Kemira
- LCI
- Natrium Products
- Occidental Chemical
- Potash Corporation
- PPG Industries
- Profile Products
- PVS
- Reagent Chemical
- Solvay
- Thymly Products
- Tolco Corporation
Maryland Chemical Company
est. 1953
