This standard specifies the spectrophotometric method for the determination of the chromaticity of 50% aqueous solution of industrial caprolactam.
GB/T 13255.1-1991 history
2009GB/T 13255.1-2009 Test methods of caprolactam for industrial use.Part 1:Determination of colourity of 50% aqueous caprolactam solution.Spectrometric method
1991GB/T 13255.1-1991 Caprolactam for industrial use--Determination of colourity of 50% aqueous caprolactam solution--Spectromeric method