Performance analysis of fabric color fastness

 

The tests of color fastness generally include color fastness to light, color fastness to weather, color fastness to washing, color fastness to rubbing, color fastness to perspiration, etc. Usually, when the color fastness test is carried out, it is the degree of discoloration of the dyed object and the degree of staining on the substrate. The color fastness is graded, except for the color fastness to light, which is grade 8, and the rest are grade 5. The higher the number, the better the color fastness.

 

The nature or degree of variation in dyeing state can be expressed by color fastness. The color fastness of the fabric is related to the type of fiber, yarn structure, fabric structure, printing and dyeing method, dye type and external force.

 

Light fastness: Light fastness refers to the degree of discoloration of colored fabrics by sunlight. The test method is to compare the fading degree of the sample after simulating sunlight with the standard color sample, and it is divided into 8 grades, with grade 8 being the best and grade 1 the worst. Fabrics with poor light fastness should not be exposed to the sun for a long time, and should be dried in the shade in a ventilated place.

 

Washing fastness: Washing or soaping fastness refers to the degree of color change of dyed fabrics after being washed with washing liquid. The gray grading sample card is usually used as the evaluation standard, that is, the color difference between the original sample and the sample after fading is used for evaluation. Washing fastness is divided into 5 grades, grade 5 is the best and grade 1 is the worst. Fabrics with poor washing fastness should be dry-cleaned. If wet-cleaned, you need to pay more attention to the washing conditions, such as the washing temperature should not be too high, and the washing time should not be too long.

 

Rubbing fastness: Rubbing fastness refers to the degree of color fading of dyed fabrics after rubbing, which can be both dry rubbing and wet rubbing. The rubbing fastness is evaluated based on the degree of staining of the white cloth, which is divided into 5 grades. The larger the value, the better the rubbing fastness.

 

Perspiration fastness: Perspiration fastness refers to the degree of color fading of dyed fabrics after a small amount of sweat.

 

Ironing fastness: Refers to the degree of discoloration or fading of dyed fabrics when ironed.

 

Sublimation fastness: refers to the degree of sublimation of dyed fabrics during storage. The color fastness of normal fabrics is generally required to reach level 3-4 to meet the needs of wearing.

 

Perspiration fastness: The sample is sewn together with the standard lining fabric, treated in perspiration solution, clamped on the perspiration color fastness tester, placed in an oven at constant temperature, then dried, rated with gray card, and obtained Test Results. Different test methods have different proportions of perspiration liquid, different sample sizes, different test temperatures and time.