Measure the Color of Wet and Dry Denim Yarn

How to Measure the Color of Wet and Dry Denim Yarn

Denim yarn must be on-color to ensure a harmonious finished garment. An inline color control solution measures wet and dry yarn color after dyeing to identify deviations so yarn can be sorted by shade for shipment.

Challenges

Color consistency is a challenge for denim yarn manufacturers:

• Individual fibers are dyed with indigo pigments and multiple dyes to achieve a specific color
• Denim yarn develops different color tones during indigo dyeing due to variations in reducing agents
• Many parameters on the dyeing machine influence color, including dye concentration, chemistry, temperature, and length of time in the dye bath
• Denim yarn color can shift once dry
• Denim dye shops must adhere to sustainability initiatives

Solution

An inline color control solution can monitor wet and dry denim yarn at multiple times in the dye process to evaluate color quality. The non-contact ERX130 spectrophotometer is mounted over the rollers on a traversing beam at a distance of 300mm (11.8”) or on an inspection table for spot measurements. With a 90mm (3.5”) measurement field, the ERX130 takes stable readings and reports color data through QC software so operators can take countermeasures and track ISO compliance.

Results

Using an inline system, denim manufacturers can:

• Shorten start-up and shade change times by 20-50%
• Intervene early to improve quality 25-35%
• Reduce waste 20-50%
• Document the process for ISO 9001
• Work toward sustainability initiatives

How it Works

Bath Dyeing:

1. The textile is immersed in the dye bath at the beginning of the machine.
2. The ERX 130 is mounted on a traversing beam over the yarn rollers to capture color measurements on the wet yarn from middle to left to right.
3. Measurement data is sent to QC software so operators can evaluate consistency and regulate contact pressure on the padder rollers to squeeze out excess dye for color control.

Rope Dyeing:

1. The individual denim fibers are combined after dyeing and measured as a bundle. Small strings may need to be combined as multiple strings to create a larger measurement area.
2. The ERX130 is mounted on a traversing beam to capture color measurements middle to left ot right as the rollers move forwards and backwards.
3. With its large measuring spot, the ERX130 detects many fibers to capture a reliable measured value.
4. Measurement data is sent to QC software so operators can evaluate color consistency and sort yarn by shade.

Final QC:

1. Fixing, washing and drying also influence denim color so color can be checked again before shipment.
2. The ERX130 is mounted on an inspection table to take spot measurements.
3. Measurement data is sent to QC software so operators can evaluate color consistency and take countermeasures before shipment.

Featured Products

ERX130 Spectrophotometer

This durable non-contact spectrophotometer has a 30mm aperture, wavelength interval of 330 nm to 730 nm, and optical resolution of 1 nm. It offers excellent inter-instrument agreement and short- and long-term stability. Even with textured yarn, it captures homogeneous textile color measurements similar to d:8° geometry for reliable results.

ESWin Quality Control Software

Quality control software used to control measurement devices and calculate color values in 1 nm steps, enabling the machine operators and quality controllers to verify color is in tolerance.

Achieve Color Success

An inline color control solution from X-Rite helps denim yarn dyers monitor color quality of wet and dry yarn so color issues can be addressed and yarn can be sorted for color harmony.