The chemical structure and production cost of vat black BBN and vat black DB are analyzed. The process conditions of yarn dyeing with these two dyes are introduced as well as the attentions in dyeing.

分析了还原黑BBN和还原黑DB的结构特点和生产成本，具体介绍了纱线染色的工艺条件，以及染色过程中需注意的事项。

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Mr Black also called on the Welsh Government to make representations to the UK government to reduce the rate of VAT on building repairs and improvement work to existing buildings from 20% to 5%.

BBC: Welsh Liberal Democrats debate