?- Bathco Ltd
- Bilbaina de Alquitranes
S.A.
- Coopers Creek chemical corporation
- Crowley Chemical Company Inc.
- DEZA a. s
- Hengshui Zehao Chemicals Co. Ltd.
- Himadri Speciality Chemicals Ltd
- JFE Chemical Corporation
- Koppers Inc.
- Mitsubishi Chemical Corporation.
- Neptune Hydrocarbons Mfg. Pvt. Ltd.
- Rain Carbon Inc
- Shandong Jiefuyi