Molecular Reduction
Proportional values representing the breakdown of molecular bonds indicate whether a finished garment is safe for skin contact. In the context of dyeing, cleavage yield refers to the percentage of azo bonds reduced by a reducing agent during a fastness test. This figure determines whether a banned aromatic amine is released at levels exceeding the legal limit.
Safety Threshold
Safety testing relies on this figure to determine if restricted chemical compounds are present. Laboratories use gas chromatography to measure the substances released when a dye molecule is split by sodium dithionite. A high cleavage yield for certain restricted dyes indicates that the garment could release carcinogenic compounds when in contact with human skin.
Standard safety protocols usually set the threshold for these amines at 20 or 30 parts per million to ensure consumer protection.
Quantification Method
Calculation of the result is expressed as a ratio between the mass of the recovered amine and the theoretical maximum that could be produced from the sample. High cleavage yield values are associated with specific temperature and reaction time conditions that must be strictly controlled to prevent underestimating the risk.
Structural Stability
Verification of this property is a mandatory step for any product entering regulated markets like the European Union. Manufacturers select pigments based on their resistance to chemical breakdown.
