ISO Standards to determine the colorfastness of polyester fibers

Colorfastness of polyester fibers is a crucial quality indicator for textiles, as it determines how well the fabric retains its color when exposed to various environmental factors. Compared to many natural fibers like cotton, polyester generally exhibits excellent colorfastness due to its hydrophobic (water-repelling) and crystalline structure.

Several ISO 105 standards are used to determine the colorfastness of polyester fibers. ISO 105 is a comprehensive series of standards that provides a structured framework for testing how textile colors perform under various conditions

Commonly used ISO 105 standards for polyester

• ISO 105-B02 (Artificial light): This standard determines the colorfastness of polyester fibers to artificial light. A specimen of the textile is exposed to artificial light, which simulates natural daylight, along with a set of blue wool references. The colorfastness is assessed by comparing the change in color of the test specimen with the references.

• ISO 105-C06 (Laundering): This standard evaluates the colorfastness to domestic and commercial laundering. A textile specimen is agitated with an adjacent fabric in a soap solution under controlled conditions of time and temperature. The change in color of the specimen and any staining of the adjacent fabric are then assessed using a grey scale.

• ISO 105-E01 (Water): This standard measures the colorfastness to water. The textile is immersed in water and then subjected to pressure in a test device at a prescribed temperature. The color change and any staining on the adjacent fabric are then assessed.

• ISO 105-X12 (Rubbing): This standard determines the colorfastness to rubbing (also known as crocking). A specimen is rubbed with a standard white cloth under controlled conditions. This test is performed for both dry and wet states to evaluate the amount of color transfer.

These standards are crucial for predicting how polyester fabrics will perform in real-world conditions, from everyday wear and washing to exposure to sunlight and sweat. They help manufacturers ensure that their products meet quality requirements and prevent issues like color bleeding or fading.