Spectrophotometry in the Textile Industry: Ensuring Colour Consistency in Denim Production

A key to achieving success in the fashion market is ensuring consistency throughout a line of clothing. A line of shirts has to have the same type of cut, quality, and colour to maintain the integrity of a brand.

Because denim can be one of the toughest fabrics to work with, maintaining colour consistency from factory to factory for a particular brand of jeans is extremely difficult. Ensuring consistent colour measurement throughout a roll of denim requires a manufacturer to make use of precise measuring equipment, such as spectrophotometers/colorimeters.

Challenges of Dyeing Denim

Denim can be a challenging fabric to use for clothing manufacturing for a variety of reasons. The weaving required to create a roll of denim fabric requires precise manufacturing work, but also provides the toughness denim is known to possess.

Those challenges carry over to dyeing denim, where the weaving pattern in the fabric can make it difficult to consistently spread the dye across the entire roll. A couple of options for dyeing denim are Indigo and sulfur dyeing.

• Indigo dyeing is commonly used in denim manufacturing, as few other dyes can match the desirable sky blue colour an Indigo dye can create. However, the Indigo dyeing process, if not performed correctly, can lead to undesirable fading after washing.
• A sulfur dye will typically be a lower-cost option for dyeing denim than Indigo, but the colour choices are a bit more limited. Most manufacturers will stick to a darker colour when using sulfur dyeing. Non-blue colours are common with sulfur dyeing too.

Nothing’s Better Than Faded Jeans

One of the best properties of denim is the way the fabric fades over time. The faded look can be even more desirable than the original dyed colour of the jeans.

For example, one reason why denim created in Japan is popular is because of the way it fades. Individual brands of Japanese denim are well known for the specific colours they produce after they fade, but those faded colours must be consistent over time to maintain the brand’s integrity.

To achieve a consistent fading process, the dye the manufacturer applies in the production phase must be consistent from fabric roll to fabric roll. A mistake in the original dyeing process will lead to a different faded colour than what’s intended, which can be a disaster for a manufacturer of fashion jeans. Therefore, finding a way to consistently ensure the colour of the denim dye process is important, which is where spectrophotometers/colorimeters enter the picture.

How Do I Get the Most Precise Colour Measurements for Denim?

Achieving repeatable colour in denim production requires measurement precision that accounts for the fabric's unique characteristics. Here's how to optimize your measurement process for maximum accuracy and consistent results.

Use Spectrophotometers

While a few other methods of measuring the colour accuracy of denim are available for use, spectrophotometers/colorimeters provide the best results. These devices offer precise, objective colour data that captures the subtle variations critical for maintaining brand identity and predicting fade patterns. By measuring spectral reflectance across the visible spectrum, this equipment can detect colour differences that are beyond the limits of human perception but essential for upholding consistent quality.

Average Sample Data

It’s important to create a sample average to negate the possibility of a slight flaw or odd variable affecting the measurement. With the weaving involved in creating denim, it’s important to take samples of different orientations, which will compensate for differences in the measurements based on the direction of the fibers. For the best results, consider turning the fabric sample by 90 degrees each time you take a sample measurement with a spectrophotometer, and then average the results.

Why Is the Agera L2 the Ideal Colour Measurement Solution for Denim?

Learn how the new, innovative Agera L2 from HunterLab helps you master colour confidence in denim production.

Capability to Capture True Denim Appearance Accurately and Efficiently

When it comes to choosing the denim consumers want to add to their wardrobe, appearance is the priority. Agera L2 makes this evaluation fast and easy with:

• Dark Performance Mode: We've specially engineered this solution to provide high-precision readings of the darkest raw denim, from deep indigo to dark charcoal and black. This device empowers 6x precision improvements in samples below 20% reflectance.
• Automated sample rotation: While other instruments require manual sample repositioning, the Agera L2's built-in sample rotation feature automatically turns samples between measurements at specified degree intervals. This eliminates orientation-related variability and simplifies sample averaging, ensuring consistent results across denim's directional weave patterns.
• Reference-grade 0°/45° circumferential optical geometry with Certified Grade ‘A’ CIE D65 illumination: This combination replicates how human eyes see colour under natural daylight, making it the ideal way to quantify true denim appearance as consumers will experience it in everyday wear.
• Extra-large area of measurement: This spectrophotometer/colorimeter measures across 4 to 16 times the surface area of typical devices on the market. The more expansive view reduces sample averaging needs and supports better data capture in patterned, textured samples — perfect for denim's weave.
• Built-in camera with sample preview functionality: This feature helps operators ensure samples are correctly positioned for colour data capture, enabling more accurate results and fewer discrepancies.

Support for Brand Consistency Across Global Production

Standardized measurement protocols are a must when your operations span different lines and facilities — or the world. Our innovative Agera L2 supports colour consistency no matter where you manufacture, with features like:

• Fully self-contained colour workstation functionality: We've built in a new version of our easy-to-use software, Easymatch Essentials L2. Tablet-based navigation makes operation intuitive, and no external PC is required for measurement, analysis, data storage, or reporting.
• Data controls: Configure the device for role-based use for both operators and administrators, protecting your data security and integrity.
• Full connectivity suite: The Agera L2 features Ethernet and USB ports to keep information flowing freely. Easily view, share, export, and print data or push outcomes directly to LIMS and SPCs to help maintain your brand standards production-wide. HDMI ports allow for connections to a monitor, while USB ports simplify adding keyboard and mouse if desired.

Adaptability to Diverse Denim Production Needs

We've engineered this spectrophotometer/colorimeter for maximum flexibility and value. The Agera L2 offers:

• Measurement versatility: Easily measure various denim types from stretch to raw to processed, including surface characteristics.
• Exceptional efficiency: This device delivers insights in under 3 seconds, enabling you to make fast quality decisions or intervene sooner to reduce the potential for rejects and rework. Plus, Agera L2 stores up to 4 million records for fast retrieval, with a generous 8 GB capacity.
• Robust construction: Sturdy construction features an enclosed housing and sealed optical engine, ensuring long-lasting performance and fewer maintenance needs.

Gain Denim Colour Confidence and Consistency With HunterLab

Find the right spectrophotometer to meet your denim coloring needs with the Agera L2. HunterLab has been offering solutions for analyzing colours for more than 70 years. Please contact us to begin the process of selecting the right tool for your manufacturing requirements.