Traditional dyeing is to dissolve the dye in water and then dye it on the fiber, because natural fibers are hydrophilic. This water-based dyeing method is not suitable for polyester, because polyester has high hydrophobicity, compact structure and difficult to react. However, in some organic solvents, the amorphous region of polyester will expand, and the dyes dissolved in the solvent will enter polyester to make the dyes adhere to the fiber. The criteria for selecting organic solvents are: no combustion or high ignition point; Non toxic or little toxic; Low surface tension; It is easy to recycle and can carry out closed cycle production; Proper boiling point; The dye dissolves well; Chemical decomposition will not occur within a certain temperature; No damage to fibers; Low price and convenient supply; The specific heat and evaporation heat are small. According to the above conditions, only perchloroethylene, trichloroethylene and 1,1,1-trichloroethane are suitable dyes before acetabulum. What are the problems in solvent dyeing with disperse dyes, especially perchloroethylene.
