After the sewing thread textile is dyed, the ability of the Polyester Sewing Thread to maintain its original color can be expressed by testing various dye fastnesses. Commonly used methods for detecting dyeing fastness include washing fastness, rubbing fastness, light fastness, pressing fastness and so on.
1. Color fastness to washing
The color fastness to washing is to sew the sample together with the standard backing fabric, after washing, washing and drying, and washing under the appropriate temperature, alkalinity, bleaching and rubbing conditions, so that the test results can be obtained in a shorter time. . The gray grading sample card is usually used as the evaluation standard, that is, the evaluation is based on the color difference between the original sample and the faded sample. The washing fastness is divided into 5 grades, 5 is the best and 1 is the worst. Fabrics with poor washing fastness should be dry cleaned. If wet cleaning is carried out, more attention should be paid to the washing conditions, such as the washing temperature should not be too high, and the washing time should not be too long.
2. Dry cleaning color fastness
The same as the color fastness to washing, except that the washing is changed to dry cleaning.
3. Color fastness to rubbing
Color fastness to rubbing refers to the degree of color fading of dyed fabrics after rubbing, which can be dry rubbing and wet rubbing. The color stained on the standard rubbing white cloth is graded with a gray card, and the obtained grade is the measured color fastness to rubbing. Note that all the colors on the sample must be rubbed. The rating results are generally divided into 5 grades. The larger the value, the better the color fastness to rubbing.
4. Color fastness to sunlight
Spun Polyester Sewing Thread is usually exposed to light when in use. Light can destroy the dye and cause what is known as "fading". Colored sewing threads are discolored. degree test. The test method is to compare the fading degree of the sample after simulating sunlight exposure with the standard color sample, which can be divided into 8 grades, where 8 is the best score, and 1 is the worst. Fabrics with poor light fastness should not be exposed to the sun for a long time, and should be dried in a ventilated place.
5. Color fastness to perspiration
Perspiration fastness refers to the degree of fading of dyed fabrics after a small amount of perspiration. The sample and the standard lining fabric are sewed together, placed in the perspiration solution, clamped on the perspiration color fastness tester, placed in an oven at a constant temperature, then dried, and graded with a gray card to obtain the test result. Different test methods have different perspiration solution ratios, different sample sizes, and different test temperatures and times.
6. Color fastness to chlorine bleach
The color fastness to chlorine bleaching is to evaluate the degree of color change after washing the fabric in chlorine bleaching solution under certain conditions, which is the color fastness to chlorine bleaching.
7. Color fastness to non-chlorine bleaching
After the 40/2 polyester sewing thread is washed with non-chlorine bleaching conditions, the degree of color change is evaluated, which is the non-chlorine bleaching color fastness.
8. Color fastness to pressing
Refers to the degree of discoloration or fading of a best sewing thread during ironing. After covering the dry sample with cotton lining fabric, press it in a heating device with specified temperature and pressure for a certain period of time, and then use a gray sample card to evaluate the discoloration of the sample and the staining of the lining fabric. The color fastness to hot pressing includes dry pressing, wet pressing and wet pressing. The specific test method should be selected according to different customer requirements and test standards. Color fastness to saliva: attach the sample to the specified lining fabric, put it in artificial saliva, remove the test solution, place it between two flat plates in the test device and apply the specified pressure, and then place the sample Dry separately from the backing fabric, and evaluate the discoloration of the sample and the staining of the backing fabric with a gray card.
9. Color fastness to saliva
Attach the sample to the specified backing fabric, put it in artificial saliva, remove the test solution, place it between two flat plates in the test device and apply the specified pressure, and then dry the sample and the backing fabric separately. , Use the gray card to evaluate the discoloration of the sample and the staining of the lining fabric.
Post time: Sep-19-2022