| 2021 |
| 09/13 | （IR情報）15:00 当社株式の上場廃止に関するお知らせ |
| 09/13 | 1,827 | 1,827 | 1,826 | 1,826 | 0% | 1,200 | 209億9900万 | +0.05% |
| 09/10 | 1,826 | 1,826 | 1,826 | 1,826 | 0% | 2,400 | 209億9900万 | +0.05% |
| 09/09 | 1,826 | 1,826 | 1,826 | 1,826 | +0.05% | 3,000 | 209億9900万 | +0.05% |
| 09/08 | 1,825 | 1,825 | 1,825 | 1,825 | 0% | 500 | 209億8750万 | 0% |
| 09/07 | 1,826 | 1,826 | 1,825 | 1,825 | -0.05% | 1,200 | 209億8750万 | 0% |
| 09/06 | 1,826 | 1,826 | 1,826 | 1,826 | +0.05% | 700 | 209億9900万 | +0.05% |
| 09/03 | 1,825 | 1,825 | 1,825 | 1,825 | 0% | 4,100 | 209億8750万 | 0% |
| 09/02 | 1,825 | 1,825 | 1,825 | 1,825 | 0% | 100 | 209億8750万 | 0% |
| 09/01 | 1,825 | 1,826 | 1,825 | 1,825 | 0% | 11,000 | 209億8750万 | 0% |
| 08/31 | 1,825 | 1,825 | 1,825 | 1,825 | 0% | 1,100 | 209億8750万 | 0% |
| 08/30 | 1,825 | 1,825 | 1,825 | 1,825 | -0.05% | 1,600 | 209億8750万 | 0% |
| 08/27 | 1,826 | 1,826 | 1,825 | 1,826 | +0.05% | 600 | 209億9900万 | +0.05% |
| 08/26 | 1,825 | 1,826 | 1,825 | 1,825 | +0.05% | 8,300 | 209億8750万 | 0% |
| 08/24 | 1,824 | 1,824 | 1,824 | 1,824 | 0% | 2,200 | 209億7600万 | -0.05% |
| 08/23 | 1,824 | 1,824 | 1,824 | 1,824 | +0.05% | 11,300 | 209億7600万 | -0.05% |
| 08/20 | 1,823 | 1,823 | 1,823 | 1,823 | -0.05% | 2,100 | 209億6450万 | -0.11% |
| 08/19 | 1,821 | 1,824 | 1,821 | 1,824 | 0% | 10,800 | 209億7600万 | -0.05% |
| 08/18 | 1,824 | 1,824 | 1,810 | 1,824 | -0.11% | 6,400 | 209億7600万 | -0.05% |
| 08/17 | （IR情報）16:00 代表取締役の異動及び役員人事に関するお知らせ |
| 08/17 | （IR情報）16:00 株式併合及び定款の一部変更に係る承認決議に関するお知らせ |
| 08/17 | 1,826 | 1,826 | 1,823 | 1,826 | 0% | 11,000 | 209億9900万 | +0.05% |
| 08/16 | 1,824 | 1,826 | 1,824 | 1,826 | 0% | 2,300 | 209億9900万 | +0.05% |
| 08/12 | 1,824 | 1,826 | 1,780 | 1,826 | 0% | 7,700 | 209億9900万 | +0.05% |
| 08/11 | （IR情報）16:00 2022年3月期第1四半期決算短信〔日本基準〕(連結) |
| 08/11 | 1,824 | 1,826 | 1,824 | 1,826 | +0.05% | 2,300 | 209億9900万 | +0.05% |
| 08/10 | 1,824 | 1,825 | 1,824 | 1,825 | +0.05% | 700 | 209億8750万 | 0% |
| 08/05 | 1,824 | 1,824 | 1,823 | 1,824 | 0% | 1,600 | 209億7600万 | -0.05% |
| 08/04 | 1,823 | 1,824 | 1,823 | 1,824 | -0.05% | 4,800 | 209億7600万 | -0.05% |
| 08/03 | 1,824 | 1,825 | 1,824 | 1,825 | +0.05% | 10,200 | 209億8750万 | 0% |
| 08/02 | 1,824 | 1,824 | 1,824 | 1,824 | 0% | 1,700 | 209億7600万 | -0.05% |
| 07/27 | 1,825 | 1,825 | 1,824 | 1,824 | 0% | 2,300 | 209億7600万 | -0.05% |
| 07/26 | 1,824 | 1,824 | 1,824 | 1,824 | 0% | 1,000 | 209億7600万 | -0.05% |
| 07/20 | 1,824 | 1,824 | 1,824 | 1,824 | 0% | 300 | 209億7600万 | -0.05% |
| 07/19 | 1,825 | 1,825 | 1,824 | 1,824 | -0.05% | 300 | 209億7600万 | -0.05% |
| 07/16 | 1,824 | 1,825 | 1,824 | 1,825 | 0% | 10,700 | 209億8750万 | 0% |
| 07/15 | 1,825 | 1,825 | 1,825 | 1,825 | 0% | 200 | 209億8750万 | 0% |
| 07/14 | 1,825 | 1,825 | 1,825 | 1,825 | 0% | 400 | 209億8750万 | 0% |
| 07/13 | 1,825 | 1,825 | 1,824 | 1,825 | 0% | 13,900 | 209億8750万 | 0% |
| 07/12 | 1,823 | 1,825 | 1,823 | 1,825 | 0% | 3,800 | 209億8750万 | -0.05% |
| 07/09 | （IR情報）15:00 株式併合並びに単元株式数の定めの廃止及び定款の一部変更に関する臨時株主総会開催に関するお知らせ |
| 07/09 | （IR情報）15:00 自己株式の消却に関するお知らせ |
| 07/09 | （IR情報）15:00 取締役の異動に関するお知らせ |
| 07/09 | 1,825 | 1,825 | 1,825 | 1,825 | 0% | 1,800 | 209億8750万 | -0.05% |
| 07/08 | 1,825 | 1,825 | 1,825 | 1,825 | 0% | 100 | 209億8750万 | -0.05% |
| 07/07 | 1,825 | 1,825 | 1,824 | 1,825 | -0.11% | 1,300 | 209億8750万 | -0.05% |
| 07/06 | 1,827 | 1,827 | 1,827 | 1,827 | +0.05% | 100 | 210億1050万 | +0.05% |
| 07/05 | 1,825 | 1,826 | 1,825 | 1,826 | -0.05% | 900 | 209億9900万 | 0% |
| 07/02 | 1,827 | 1,827 | 1,827 | 1,827 | +0.11% | 200 | 210億1050万 | +0.05% |
| 07/01 | （IR情報）15:00 支配株主等に関する事項について |
| 07/01 | 1,827 | 1,827 | 1,823 | 1,825 | -0.05% | 12,100 | 209億8750万 | -0.05% |
| 06/30 | 1,825 | 1,826 | 1,825 | 1,826 | +0.05% | 300 | 209億9900万 | 0% |
| 06/29 | 1,825 | 1,826 | 1,824 | 1,825 | 0% | 7,200 | 209億8750万 | -0.05% |
| 06/28 | 1,828 | 1,828 | 1,820 | 1,825 | -0.11% | 16,000 | 209億8750万 | -0.05% |
| 06/25 | 1,828 | 1,828 | 1,827 | 1,827 | +0.11% | 300 | 210億1050万 | +0.05% |
| 06/24 | 1,825 | 1,825 | 1,825 | 1,825 | 0% | 800 | 209億8750万 | -0.05% |
| 06/23 | 1,823 | 1,826 | 1,823 | 1,825 | 0% | 2,900 | 209億8750万 | -0.05% |
| 06/22 | 1,828 | 1,828 | 1,825 | 1,825 | 0% | 500 | 209億8750万 | -0.05% |
| 06/21 | 1,826 | 1,826 | 1,824 | 1,825 | -0.16% | 700 | 209億8750万 | -0.05% |
| 06/18 | 1,827 | 1,828 | 1,827 | 1,828 | +0.16% | 300 | 210億2200万 | +0.05% |
| 06/17 | 1,824 | 1,828 | 1,822 | 1,825 | 0% | 10,200 | 209億8750万 | -0.11% |
| 06/16 | 1,828 | 1,829 | 1,823 | 1,825 | 0% | 4,200 | 209億8750万 | -0.11% |
| 06/15 | （IR情報）15:00 臨時株主総会招集のための基準日設定に関するお知らせ |
| 06/15 | 1,824 | 1,825 | 1,824 | 1,825 | +0.11% | 4,800 | 209億8750万 | -0.11% |
| 06/14 | （5%ルール）三井化学（49.9%）三井物産（34.58%） |
| 06/14 | 1,822 | 1,824 | 1,822 | 1,823 | 0% | 2,400 | 209億6450万 | -0.22% |
| 06/12 | （IR情報）11:00 三井化学株式会社及び三井物産株式会社による当社株券に対する公開買付けの結果並びに主要株主である筆頭株主の異動に関するお知らせ |
| 06/11 | 1,821 | 1,825 | 1,821 | 1,823 | -0.11% | 17,800 | 209億6450万 | -0.22% |
| 06/10 | 1,825 | 1,826 | 1,825 | 1,825 | -0.16% | 6,600 | 209億8750万 | -0.11% |
| 06/09 | 1,828 | 1,828 | 1,828 | 1,828 | 0% | 10,800 | 210億2200万 | +0.05% |
| 06/08 | 1,828 | 1,829 | 1,828 | 1,828 | 0% | 17,300 | 210億2200万 | +0.05% |
| 06/07 | 1,829 | 1,829 | 1,828 | 1,828 | -0.05% | 30,900 | 210億2200万 | +0.05% |
| 06/04 | 1,828 | 1,829 | 1,828 | 1,829 | 0% | 55,100 | 210億3350万 | +0.11% |
| 06/03 | 1,828 | 1,829 | 1,828 | 1,829 | +0.05% | 11,500 | 210億3350万 | +0.16% |
| 06/02 | 1,828 | 1,828 | 1,828 | 1,828 | 0% | 119,000 | 210億2200万 | +0.11% |
| 06/01 | 1,827 | 1,828 | 1,827 | 1,828 | +0.05% | 243,400 | 210億2200万 | +0.11% |
| 05/31 | 1,827 | 1,830 | 1,827 | 1,827 | 0% | 148,500 | 210億1050万 | +0.05% |
| 05/28 | 1,828 | 1,828 | 1,827 | 1,827 | 0% | 24,500 | 210億1050万 | +0.05% |
| 05/27 | 1,827 | 1,828 | 1,826 | 1,827 | +0.05% | 59,800 | 210億1050万 | +0.05% |
| 05/26 | 1,826 | 1,827 | 1,826 | 1,826 | 0% | 18,800 | 209億9900万 | 0% |
| 05/25 | 1,826 | 1,827 | 1,826 | 1,826 | 0% | 111,000 | 209億9900万 | 0% |
| 05/24 | 1,827 | 1,828 | 1,826 | 1,826 | 0% | 55,600 | 209億9900万 | 0% |
| 05/21 | 1,827 | 1,828 | 1,826 | 1,826 | -0.05% | 49,500 | 209億9900万 | 0% |
| 05/20 | 1,827 | 1,828 | 1,826 | 1,827 | +0.05% | 31,800 | 210億1050万 | +0.11% |
| 05/19 | 1,827 | 1,828 | 1,826 | 1,826 | -0.05% | 18,900 | 209億9900万 | +0.05% |
| 05/18 | 1,829 | 1,829 | 1,826 | 1,827 | -0.16% | 28,500 | 210億1050万 | +0.11% |
| 05/17 | 1,828 | 1,832 | 1,826 | 1,830 | +0.11% | 116,400 | 210億4500万 | +0.27% |
| 05/14 | （IR情報）16:00 三井化学株式会社及び三井物産株式会社による当社株券に対する公開買付けに関する賛同の意見表明及び応募推奨のお知らせ |
| 05/14 | （IR情報）16:00 役員の異動に関するお知らせ |
| 05/14 | （IR情報）16:00 2021年3月期決算短信〔日本基準〕(連結) |
| 05/14 | 1,827 | 1,835 | 1,826 | 1,828 | +0.22% | 38,500 | 210億2200万 | +0.16% |
| 05/13 | 1,824 | 1,828 | 1,822 | 1,824 | -0.16% | 15,700 | 209億7600万 | -0.05% |
| 05/12 | 1,825 | 1,829 | 1,824 | 1,827 | +0.11% | 7,000 | 210億1050万 | +0.11% |
| 05/11 | 1,824 | 1,825 | 1,820 | 1,825 | 0% | 30,600 | 209億8750万 | 0% |
| 05/10 | 1,824 | 1,827 | 1,824 | 1,825 | -0.16% | 1,500 | 209億8750万 | 0% |
| 05/07 | 1,828 | 1,830 | 1,826 | 1,828 | 0% | 2,200 | 210億2200万 | +0.16% |
| 05/06 | 1,824 | 1,829 | 1,824 | 1,828 | +0.22% | 6,600 | 210億2200万 | +0.16% |
| 04/30 | 1,825 | 1,825 | 1,824 | 1,824 | -0.05% | 9,400 | 209億7600万 | 0% |
| 04/28 | 1,825 | 1,825 | 1,824 | 1,825 | +0.11% | 1,800 | 209億8750万 | 0% |
| 04/27 | 1,824 | 1,825 | 1,823 | 1,823 | 0% | 11,500 | 209億6450万 | -0.11% |
| 04/26 | 1,825 | 1,825 | 1,823 | 1,823 | -0.11% | 8,100 | 209億6450万 | -0.11% |
| 04/23 | 1,824 | 1,825 | 1,824 | 1,825 | 0% | 1,600 | 209億8750万 | 0% |
| 04/22 | 1,824 | 1,825 | 1,823 | 1,825 | +0.05% | 3,300 | 209億8750万 | 0% |
| 04/21 | 1,824 | 1,826 | 1,824 | 1,824 | -0.05% | 2,100 | 209億7600万 | -0.05% |
| 04/20 | 1,827 | 1,827 | 1,824 | 1,825 | -0.16% | 6,800 | 209億8750万 | 0% |
| 04/19 | 1,823 | 1,828 | 1,822 | 1,828 | +0.44% | 12,800 | 210億2200万 | +0.16% |
| 04/16 | 1,825 | 1,826 | 1,820 | 1,820 | -0.33% | 24,700 | 209億3000万 | -0.27% |
| 04/15 | 1,825 | 1,826 | 1,825 | 1,826 | +0.05% | 20,300 | 209億9900万 | +0.05% |
| 04/14 | 1,824 | 1,826 | 1,824 | 1,825 | +0.05% | 3,400 | 209億8750万 | 0% |
| 04/13 | 1,824 | 1,825 | 1,824 | 1,824 | 0% | 8,500 | 209億7600万 | -0.05% |
| 04/12 | 1,825 | 1,825 | 1,823 | 1,824 | -0.11% | 6,600 | 209億7600万 | -0.05% |
| 04/09 | 1,826 | 1,826 | 1,824 | 1,826 | 0% | 2,200 | 209億9900万 | 0% |
| 04/08 | 1,825 | 1,826 | 1,823 | 1,826 | +0.05% | 11,100 | 209億9900万 | 0% |
| 04/07 | 1,823 | 1,826 | 1,823 | 1,825 | 0% | 14,600 | 209億8750万 | -0.05% |
