The color consistency of textiles is one of the important indicators for evaluating product quality. If you want to accurately determine the color difference of textiles, you can use an accurate color difference instrument to measure it. This article introduces the method of textile color difference, which interested users can see.
Analysis of the causes of color difference in textiles:
- Fabric raw material factors
Different textiles use different fiber raw materials. Even with the same dye and coloring process, due to different fiber properties, the absorption of dyes is different, which will lead to color differences in the textile fabric.
- Dye factors
Different dye ratios and uneven dye concentrations will result in different degrees of fabric coloring. If the dye is unevenly distributed in different parts of the fabric, color differences will form after the color is fixed.
- Dyeing conditions and environmental changes
In the textile dyeing process, due to improper mechanical structure or operation, it needs to go through multiple processes, resulting in changes in coloring conditions such as temperature changes, drying rate, uneven roller pressure, uneven dyeing, etc., which will cause color difference in textile fabrics.
- Color light changes
This difference is not due to uneven distribution of dyes on the fabric, but rather to changes in the shade of certain dyes on the fabric due to some reasons.
Textile color difference control method:
In order to ensure that the color difference of textiles is within a reasonable range, we need to verify and analyze the color difference in each link of the dyeing process.
- Prepare the ingredients
Regardless of the batch size, the first step to producing a single color requires dyes from the same batch, with the same shade and concentration. Otherwise, the formula should be readjusted during the dyeing process, and samples should be taken before the samples are put into production. Strictly controlling the color difference of textile raw materials is the first step to controlling the color difference of textiles.
- Sample
Textile samples should be prepared strictly according to the dosage and operating procedures of the formula. The process and technical conditions of the samples, including pressure, speed, temperature, concentration, etc., must be the same as those of normal production to determine the color difference of the samples and avoid color difference losses caused by batch production.
- Monitoring
Although color differences in formulas can be verified to a certain extent through samples, in actual production, it is difficult to completely align production processes between batches, and they are affected by various factors such as labor and equipment. Therefore, certain color differences will still occur during large-scale production, necessitating the use of specialized color verification equipment. If a colorimeter is used to perform random inspections of manufactured products, any significant color differences must be promptly identified to ensure strict control of textile color differences.
Textile colorimeter control measures:
In order to accurately evaluate the color difference of textiles and control the quality of textiles, a colorimeter can be used for testing. The use of a colorimeter makes the color processing of textiles more convenient. We use a colorimeter and a computer color matching system to change the color of textile products, thereby reducing the color difference between textile products in the same batch.
The colorimeter can accurately evaluate the color difference between two products. It can automatically compare the color difference between the model and the inspected product, and then output three sets of CIE-LAB data and four sets of color difference data after colorimetry: ΔE, ΔL, Δa, and Δb.
The principle behind this technique is to measure the sample’s three stimulus values (x, y, and z) by integrating them, and then calculate the sample’s color coordinates and other parameters. The detector is typically covered with a filter to correct the detector’s relative spectral sensitivity (S(λ)) to the CIE-recommended spectral tristimulus values (x(λ), y(λ), and z(λ). When these three light detectors are used to receive light stimuli, the sample’s three stimulus values (X, Y, and Z) can be measured using a single integral. To accurately match the light detector, the filter must meet the Luther condition.
Textile manufacturers can color textiles with large color differences based on the data measured by the colorimeter to ensure product color consistency and reduce corresponding losses.
What is the color difference grade of textiles?
What is the standard for color difference between the edge and center of fabric?
After dyeing, fabrics are prone to color differences between the center and edge, as well as between the left, center, and right sides. To control clothing quality and grade, it’s necessary to set standards for color differences between the center and edge of fabrics. This article explains the color difference level requirements for the center and edge of fabrics, and the principles of colorimeter testing.
What is the standard for color difference between the edges of fabrics?
Color difference in the center of the fabric edge is a common problem for dyed fabrics and is also difficult to overcome. Today, the clothing industry has increasingly stringent requirements for color difference in the center of the fabric edge, with some even requiring it to reach level 4 or above. According to the national standard GB250 and GB251 textile color card standards, the color difference standard for visual color comparison of clothing is divided into 5 levels, with level 5 being no color difference. Generally, the color difference requirement for first-class products is level 4 (including the center edge and the beginning and end). However, there is no standard requirement for color difference compared with the standard color, which depends on the agreement between the supply and demand parties. The specific grade standards are as follows:
Level 5: Color difference requirement is 0, tolerance requirement is 0.2;
Level 4-5: color difference requirement is 0.8, tolerance requirement is ±0.2;
Level 4: color difference requirement is 1.7, tolerance requirement is ±0.3;
Level 3-4: Color difference requirement is 2.5, tolerance requirement is ±0.35
Level 3: color difference requirement is 3.4, tolerance requirement is ±0.4;
Level 2-3: color difference requirement is 4.8, tolerance requirement is ±0.5;
Level 2: color difference requirement is 6.8, tolerance requirement is ±0.6;
Level 1-2: color difference requirement is 9.6, tolerance requirement is ±0.7;
Level 1: color difference requirement is 13.6, tolerance requirement is ±1.0;