Color Fastness To Light
Colorfastness to light is an offline quality assurance system. Generally, a man wears the fabric and goes outside of the home for doing their job. During the day, sunlight falls on the fabric’s surface. So it needs to know how much protection ability has a fabric to sunlight. Hence, it is determined by an experiment called colorfastness to light. However, colorfastness to light mostly depends on the depth of shade, humidity, temperature, presence of unwanted chemicals, presence of atmospheric impurities, and intensity of the incident light and spectral quality.
Colorfastness to light emphatically refers to the ability of the fabric to withstand sunlight. The following points determine the resistance to sunlight. They are-
- Firstly, the intensity of light.
- Secondly, season.
- Thirdly, the inherent properties of the fabric
- Then, the distance from the equator
- Finally, the altitude
Color Fastness Test Methods
There are two methods identically for colorfastness to light measurement. They are-
The sunlight method is a direct method evidently for measuring the color fastness of the fabric. However, to perform this test samples take place in a glass cabinet and are exposed to sunlight from 9 am to 3 pm.
Laboratory Instrument Method:
The colorfastness to light is also performed by the use of laboratory instruments. The following instruments are used to perform the test. They are-
Additionally, to perform this measurement a carbon-arc lamp or xenon-arc lamp is used in these machines as the light source.
Measure the fastness to light with the Microsol light fastness tester:
Here, I have given a lightfastness measurement system by Microsol light fastness tester.
The testing is done step by step and accordingly to the procedure. The following step is maintained during measuring the color fatness to light. They are-
- Firstly, cut the four pieces of test specimens according to the length & width-wise and attached them to the specimen holder.
- Secondly, the holder is set into the Microsol light fastness tester.
- Thirdly, the experiment continued for 72 hours according to the buyer’s requirement.
- After 72 hours later the specimen was taken from the light fastness tester
- Lastly, the test specimen compare with the Blue scale or computer color matching system (CCMS).
Light Fastness Scale:
To measure the colorfastness to light generally a blue scale is used. However, after completing the test, the sample is compared with the blue scale.
|Grade||Degree of Fading||Light Fastness Type|
|7||Very slight fading||Excellent|
|6||Slight fading||Very good|
|1||Very extensive fading||Very poor|
So, we should measure the lightfastness according to the testing procedure.