May 1954
| The goverment of the Czechoslovak Socialist Republic adopted a decision on the construction of the synthetic butadiene-styrene rubber production plant in Kralupy nad Vltavou |
4.6. 1958
| Kaučuk national corporation start-of-construction ceremony |
1. 7. 1963
| Field test launch (KRASTEN polystyrene production) |
4. 11. 1963
| Produced first wagon of synthetic rubber under trade mark KRALEX |
13. 3. 1965
| Produced first KOPLEN expandable polystyrene |
October 1969
| Commenced building of an copolymer ABS (acrylonitrile butadiene styrene) production plant |
January 1971
| Oil refinery start-of-construction ceremony |
25. 4. 1975
| Launched production of oil |
1. 9. 1976
| After change of technology a test run at the ABS FORSAN production plant was successfully launched |
25. 11. 1983
| Produced the millionth ton of KRALEX rubber |
1. 4. 1990
| Kaučuk company becomes a national corporation |
24. 2. 1993
| The Britisch company LRQA awarded the corporacion a certificate confirming compliance of Management System of the rubber production with ISO 9002 standards |
August 1995 | Kaučuk is awarded the so-called corporate certificate pursuant to international standard ISO 9002 |
31. 12. 1995
| The refinery is separated and joined with the newly established company Česká rafinerská, a. s. |
27. 5. 1996
| Kaučuk is transformed into a joint-stock company |
8. 10. 1996
| As one of the first in the Czech Republic, Kaučuk is awarded a „Responsible Care“ certificate - for conducting a responsible chemistry business |
27. 3. 1997
| Kaučuk becomes a member of the UNIPETROL group |
2nd half of 1997
| Production units Syren III (27. 8.) and Block Crystal Polystyrene (July) start-of-construction ceremony |
4. 6. 1998
| Produced the two millionth ton of KRALEX rubber |
10. 12. 1998
| Opening ceremony of the Styren III and Block Crystal Polystyrene production plants |
12. 12. 1999
| Kaučuk is certified according to ISO 14 000 |
1. 3. 2002
| Re-certification under the standards ISO 9001/2000 and ISO 14 000/1996 |
March 2002
| Unit Ethyl benzene II (ETB II) in Litvínov start-of-construction ceremony |
3. 6. 2003
| ETB II opening ceremony |
2004 | Reconstruction and renovation of ethylbenzene pipeline from Litvinov to Kralupy |
June 2005
| The new strategic partner PKN ORLEN entered in the UNIPETROL. |
19. 7. 2007
| Within the Group restructuring process, proceedings were launched for the sale of KAUČUK, completed on when Firma Chemiczna DWORY, S.A., Poland, a company with a similar product portfolio, acquired the ownership rights. |
2. 11. 2007
| In accordance with his strategic goals the new owner decided to change commercial name to SYNTHOS Kralupy a.s. There is another consequential change, connected with the change of the company name, which is the change of the SYNTHOS Group logo. |