{
  "spec_version": "3",
  "endpoint": "timeline",
  "stock_code": "4205",
  "company_name": "日本ゼオン",
  "content_lang": "ja",
  "meta_lang": "en",
  "canonical_url": "https://the-shashi.com/tse/4205/",
  "api_url": "/api/4205/timeline.json",
  "updated": "2026-08-12",
  "license": "© 2026 Yutaka Sugiura. All rights reserved.",
  "attribution": "The社史 (the-shashi.com) — https://the-shashi.com/tse/4205/",
  "source": {
    "primary": [
      "有価証券報告書"
    ],
    "extraction": "有価証券報告書の沿革を基礎に、社史・報道で補完",
    "row_field": "source"
  },
  "timeline": [
    {
      "date": "1950/4",
      "importance": 3,
      "event": "合成樹脂の製造販売を目的に日本ゼオンを設立",
      "source": "有価証券報告書",
      "link": "/tse/4205/decisions/goodrich-joint-venture-1950/"
    },
    {
      "date": "1952/4",
      "importance": 1,
      "event": "蒲原工場完成、塩化ビニル樹脂の生産開始",
      "source": "有価証券報告書"
    },
    {
      "date": "1956/11",
      "importance": 1,
      "event": "高岡工場完成、塩化ビニル樹脂の生産開始",
      "source": "有価証券報告書"
    },
    {
      "date": "1959/7",
      "importance": 3,
      "event": "川崎工場完成、合成ゴムの生産開始と中央研究所開設",
      "source": "有価証券報告書"
    },
    {
      "date": "1961/9",
      "importance": 1,
      "event": "東京証券取引所に上場",
      "source": "有価証券報告書"
    },
    {
      "date": "1965/7",
      "importance": 2,
      "event": "徳山工場完成、自社技術GPB法によるブタジエンの生産開始",
      "source": "有価証券報告書"
    },
    {
      "date": "1967/3",
      "importance": 1,
      "event": "塩化ビニル樹脂の生産合理化のため蒲原工場を閉鎖",
      "source": "有価証券報告書"
    },
    {
      "date": "1969/8",
      "importance": 1,
      "event": "水島工場完成、塩化ビニル樹脂の生産開始",
      "source": "有価証券報告書"
    },
    {
      "date": "1971/11",
      "importance": 2,
      "event": "水島工場に自社技術GPI法のイソプレン抽出プラント完成",
      "source": "有価証券報告書"
    },
    {
      "date": "1981/8",
      "importance": 1,
      "event": "加工品事業部門をゼオン化成として分離・独立",
      "source": "有価証券報告書"
    },
    {
      "date": "1984/4",
      "importance": 2,
      "event": "高岡工場で水素化ニトリルゴムの生産開始",
      "source": "有価証券報告書"
    },
    {
      "date": "1988/7",
      "importance": 1,
      "event": "米国にZeon Chemicals Texasを設立し現地生産開始",
      "source": "有価証券報告書"
    },
    {
      "date": "1989/3",
      "importance": 2,
      "event": "英国BP Chemicalsのニトリルゴム部門を買収",
      "source": "有価証券報告書"
    },
    {
      "date": "1989/9",
      "importance": 3,
      "event": "米国B.F.Goodrichの特殊ゴム事業を買収",
      "source": "有価証券報告書",
      "link": "/tse/4205/decisions/special-rubber-acquisitions-1989/"
    },
    {
      "date": "1990/11",
      "importance": 3,
      "event": "水島工場でシクロオレフィンポリマーの生産開始",
      "source": "有価証券報告書"
    },
    {
      "date": "1995/7",
      "importance": 2,
      "event": "塩ビ事業を切離し新第一塩ビへ移管",
      "source": "有価証券報告書"
    },
    {
      "date": "1996/4",
      "importance": 1,
      "event": "米沢市に精密化学品の米沢工場を設立",
      "source": "有価証券報告書"
    },
    {
      "date": "2000/3",
      "importance": 3,
      "event": "水島工場の塩ビ生産を打ち切り塩ビ事業から撤退",
      "source": "有価証券報告書",
      "link": "/tse/4205/decisions/pvc-exit-2000/"
    },
    {
      "date": "2001/12",
      "importance": 2,
      "event": "光学フィルム工場としてオプテス高岡製造所が完成",
      "source": "有価証券報告書"
    },
    {
      "date": "2003/9",
      "importance": 1,
      "event": "会社分割でDCPD-RIM事業部門をRIMTECへ譲渡",
      "source": "有価証券報告書"
    },
    {
      "date": "2005/3",
      "importance": 1,
      "event": "本社を千代田区丸の内の現在地に移転",
      "source": "有価証券報告書"
    },
    {
      "date": "2007/9",
      "importance": 1,
      "event": "富山県氷見市にオプテス氷見製造所が完成",
      "source": "有価証券報告書"
    },
    {
      "date": "2010/12",
      "importance": 1,
      "event": "シンガポールにZeon Chemicals Singaporeを設立",
      "source": "有価証券報告書"
    },
    {
      "date": "2012/2",
      "importance": 1,
      "event": "ベトナムにZeon Manufacturing Vietnamを設立",
      "source": "有価証券報告書"
    },
    {
      "date": "2013/3",
      "importance": 1,
      "event": "トウペを公開買付けにより子会社化",
      "source": "有価証券報告書"
    },
    {
      "date": "2013/3",
      "importance": 1,
      "event": "福井県敦賀市にオプテス敦賀製造所が完成",
      "source": "有価証券報告書"
    },
    {
      "date": "2015/11",
      "importance": 2,
      "event": "徳山工場にカーボンナノチューブ製造プラントが竣工",
      "source": "有価証券報告書"
    },
    {
      "date": "2017/4",
      "importance": 2,
      "event": "住友化学とのS-SBR統合会社ZSエラストマーが営業開始",
      "source": "有価証券報告書"
    },
    {
      "date": "2018/3",
      "importance": 1,
      "event": "英国のZeon Chemicals Europeを清算",
      "source": "有価証券報告書"
    },
    {
      "date": "2020/10",
      "importance": 1,
      "event": "敦賀工場に大型テレビ用光学フィルムのラインが竣工",
      "source": "有価証券報告書"
    },
    {
      "date": "2022/2",
      "importance": 1,
      "event": "米国のAurora Microplatesを買収",
      "source": "有価証券報告書"
    },
    {
      "date": "2022/4",
      "importance": 1,
      "event": "東京証券取引所の市場区分見直しでプライム市場へ移行",
      "source": "有価証券報告書"
    },
    {
      "date": "2023/1",
      "importance": 1,
      "event": "米国のEdge Embossingを買収",
      "source": "有価証券報告書"
    },
    {
      "date": "2024/3",
      "importance": 1,
      "event": "高岡工場にCOPのリサイクルプラントが竣工",
      "source": "有価証券報告書"
    },
    {
      "date": "2024/10",
      "importance": 2,
      "event": "住友化学とのS-SBR合弁を解消しZSエラストマーを吸収合併",
      "source": "有価証券報告書"
    }
  ]
}