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答案（中文）
限制条目 74 适用于“二异氰酸酯，通式为 O=C=NRN=C=O，其中 R 为未指定长度的脂肪族或芳香族烃单元”。这意味着该条目中的 R 基团不包含氨基甲酸酯、脲、脲二酮、缩二脲、脲基甲酸酯或异氰脲酸酯键（即，二异氰酸酯实体不是母体二异氰酸酯预聚合的产物）。该限制涵盖二异氰酸酯（作为其自身物质、作为其他物质的成分或混合物）的工业和专业用途，浓度≥0.1%（重量百分比）。因此，符合上述定义（非详尽列表如下所示）的二异氰酸酯含量≥0.1%（按重量计）的低聚物和预聚物仍在限制范围内。限制条目 74 所涵盖的二异氰酸酯物质示例：更多信息请参阅最终背景文件，该文件可在 ECHA 网站的“限制意向登记直至结果”部分中查阅。
Answer (EN)
Restriction entry 74 applies to ‘Diisocyanates, with generic formula O=C=N-R-N=C=O, with R being an aliphatic or aromatic hydrocarbon unit of unspecified length’. This means that the group R in this entry does not contain urethane, urea, uretdione, biuret, allophanate or isocyanurate linkages (i.e., the diisocyanate entity is not the result of prepolymerisation of a parent diisocyanate). The restriction covers industrial and professional uses of Diisocyanates (as substances on their own, as constituents of other substances or in mixtures) in concentration ≥0.1% by weight. As a result, oligomers and prepolymers that contain ≥0.1% (by weight) of the diisocyanates that meet the above definition (of which a non-exhaustive list is shown below), would still be in scope of the restriction.Examples of diisocyanate substances covered by restriction entry 74:More information is available in the Final background document accessible on the ECHA website in the Registry of restriction intentions until outcome section.