Black reactive dye semi-finished product and preparation method and application thereof

The invention relates to a black reactive dye semi-finished product and a preparation method and application thereof. The chemical structural general formula of the semi-finished product is shown in a formula (I), and the structural formula is as shown in the specification, wherein R1 refers to -CH3(CH2)n, -CH3(CH2)n O, -COOX or -SO3X; R2 refers to -H, -CH3(CH2)n, -CH3(CH2)n O, -COOX or -SO3X; R3 refers to -H, -CH3(CH2)n, -CH3(CH2)n O, -COOX or -SO3X; R4 refers to -H, -CH3(CH2)n, -CH3(CH2)n O, -COOX or -SO3X; R5 refers to -(CH2)-; and X can be Na, K or Li. On one hand, the black reactive dye semi-finished product has a bisazo structure, and the fixation rate and deep dyeing property of the product can be improved; on the other hand, the black reactive dye semi-finished product comprises multiple sulfonated groups, can achieve the effects similar to a surfactant, is conveniently compound and mixed with other organic matters and is dissolved in water to prepare a dye solution.