Jeans are popular with consumers because of  their durability, fashion, and universality.However, in recent years, with the enhancement of people's consumption awareness, there are more and more complaints about the quality of jeans, and the most concentrated two aspects are the color fastness and strength.What is the cause of the quality problem of jeans?How to explain it?

Washing Color Fastness Tester

The testing of washing color fastness is to combined the textile sample with two specified single fiber lining fabrics or a multi-fiber lining fabric, immerse in water, squeeze out water, place it between the two plates of the test device, and withstand the specified pressure. Put the test device with the combined sample into the incubator, keep it at a specified temperature °C for a certain period of time, separate the sample and the lining fabric separately, and evaluate the discoloration and lining of the sample with a gray sample card or spectrophotometer, stained.The equipment used: Washing Color Fastness Tester GT-D07.

Perspiration Tester

Color fastness of perspiration test includes acid fast and alkali-resistant perspiration color fastness: The principle is to suture the textile sample with the standard lining, and put it in an acid test solution containing histidine at pH (5.5±0.2) and an alkaline test solution having a pH of (8.0±0.2). Dispose of separately in the test solution.After removes the sample from solution, it is placed between the two plates in the test device to be subjected to a prescribed pressure.The device with the combined sample was placed in an incubator and held at (37 ± 2) °C for 4 h. The sample is then unrolled and suspended in air at a temperature not exceeding 60 ° C to dry. The color change of each sample and the staining of the lining fabric were evaluated using a gray sample card or instrument. The equipment used: Perspiration Tester GT-D09.

Crockmeter Rubbing Fastness Tester

Crockmeter rubbing fastness means the degree of discoloration when the fabric rubs against other fabrics in the dry state.The standard test method is: prepare one piece of (50mm ± 2mm) × (50mm ± 2mm) square white standard cotton rubbing cloth;Then take a sample with a size of not less than 50mm×140mm along the warp and weft directions of the sample.After the sample and the rubbing cloth are placed under the specified standard atmospheric pressure for at least 4 hours,The crock rubbing cloth is placed on the head of the device, and the warp direction is consistent with the running direction of the friction head; then the sample is fixed on the platform of the friction meter, so that the length direction of the sample is consistent with the running direction of the friction head. The friction was started and the running speed was 1 reciprocating friction cycle per second for a total of 10 cycles.Under a suitable light source, the number of stains of the rubbing cloth was evaluated using a gray sample card for assessing staining. The warp and weft directions of the samples were evaluated separately.The equipment used:Crockmeter Rubbing Fastness Tester GT-D05.

The reason of the unqualified color fastness:

The poor color fastness of jeans is mainly caused by the dyeing process. The first thing is to choose the right dye. The most important thing is that the dyeing process must be carried out in strict accordance with the process requirements.Especially the final solid color treatment, time and temperature must be guaranteed, in order to minimize the residual floating color, will improve the color fastness of the finished product.