Spectrophotometer Color Measurement Protocols and Batch Shade Variation Limits
Enforce CIE DE2000 spectrophotometric shade tolerance limits under dual illuminants with strict fabric conditioning to prevent batch rejections.
Side Center Side Shade Drift
Lateral Inconsistency
Transverse color inconsistencies describe the gradual or sudden changes in shade that occur between the edges and the middle of a fabric web during dyeing or finishing. A side center side shade drift is a common defect where the color near the selvedges does not match the color in the center of the roll. This problem is typically caused by uneven pressure across the padding rollers or inconsistent heating in the drying ovens.
It makes it nearly impossible to cut wide garment panels without seeing a color shift from one side of the piece to the other. The defect is quantified by taking spectrophotometer readings at the left, center and right positions of the fabric width. It is a major quality concern for producers of high width woven and knitted materials.
Mechanical Cause
Variations in the physical state of the machinery are the primary drivers of these lateral shade differences. When side center side shade drift occurs, it often points to a worn or poorly calibrated roller in the dyeing machine. If the rollers are slightly bowed, they will apply more pressure at the edges than in the middle, resulting in less dye being absorbed at the sides.
Similarly, if the air nozzles in the drying stenter are clogged at the ends, the center of the fabric will dry faster and develop a different color. Monitoring the uniformity of these mechanical forces is necessary for a stable production process. Regular maintenance of the padding and drying units is the only way to prevent the drift from exceeding acceptable limits.
Roll Mapping
Documenting the extent of the variation is required for the efficient use of the fabric in the garment factory. When a roll is identified with side center side shade drift, a detailed report is created that shows the delta e measurements across the width. This mapping allows the cutting room to decide if the fabric can be used for smaller pieces where the shift is less noticeable.
For example, a sleeve might be cut from the side and a pocket from the center, but a large coat back would show a visible line. In some cases, the edges of the fabric must be trimmed away and discarded, which increases the total cost of production. Clear communication between the mill and the cutter is essential to minimize the impact of this defect.
Marker Planning
Strategic layout of the pattern pieces is the final defense against the visual impact of lateral shading in finished garments. If the side center side shade drift is within a manageable range, the markers are designed to keep adjacent panels within the same zone of the fabric width. This ensures that the pieces sewn together have the best possible color match.
However, this level of planning adds significant time and complexity to the manufacturing process. It also reduces the fabric yield, as the nesting of pieces is less flexible. High end brands often set very strict limits on this drift to avoid these production headaches.
Maintaining a flat and uniform color across the entire width is the hallmark of a high quality textile mill.