Penetration Measurement
A quantitative metric defines the depth to which pigment or dyestuff has permeated the individual fibre or yarn structure. The core dye ingress ratio provides a numerical value for the relationship between the dyed outer ring and the undyed or lighter interior. It identifies the efficiency of a dyeing cycle in achieving a solid, through-dyed appearance.
Processing Efficiency
Industrial pressure dyeing systems aim for a high value to ensure colorfastness and prevent frosting during subsequent abrasion. A low core dye ingress ratio often results from shortened cycle times or insufficient carrier chemicals in the bath. Penetration varies.
The absence of saturation creates a ring-dyed effect where the centre remains white.
Visual Appearance
Fabric appearance changes when surface fibres are disrupted if the internal core lacks colour. Weavers monitor the core dye ingress ratio to predict how denim or heavy canvas will age under mechanical stress. High ratios maintain shade depth even as the surface wears away through washing or friction.
Microscopic Evaluation
Analysis requires a cross-sectional cut of the yarn viewed under magnification. Technicians measure the diameter of the coloured zone against the total yarn diameter to calculate the percentage of saturation. The data allows for adjustments in temperature ramps or hold times within the dye vat.
