Color Fastness To Light Test Procedure

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 to do their job. During the day, sunlight falls on the fabric’s surface. So it needs to know how much protection a fabric has from 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, 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-

Sunlight Method:

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-

  1. Fade-o-meter
  2. Weather-o-meter

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 lightfastness tester.

The testing is done step by step and according 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 their length and width and attach 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 requirements.
  • After 72 hours, the specimen was taken from the light fastness tester
  • Lastly, the test specimen is compared 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.

GradeDegree of FadingLight Fastness Type
8No fadingOutstanding
7Very slight fadingExcellent
6Slight fadingVery good
5Moderate fadingGood
4Appreciable fadingModerate
3Significant fadingFair
2Extensive fadingPoor
1Very extensive fadingVery poor

So, we should measure the lightfastness according to the testing procedure.

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  • Shapad Das

    Understanding color fastness to light is crucial for evaluating fabric’s ability to withstand sunlight. It’s great to know about the two methods – sunlight and laboratory instrument methods, and the Microsol light fastness tester seems like an efficient tool for measurement. Thanks for the detailed explanation!

  • Thanks for your sharing. The light tester is a useful tool.

  • Light fastness tester is a good machine, to determine color fastness to light, weather and light aging of various colored textiles and other materials by simulating both light and dark cycles and nature weather conditions by specimen holder and rack sprays and long-arc-xenon lamp equipped

  • It is a good machine for textile testing, and wild range of use. Light & Weather Fastness Tester complies with ISO105-B02/B04, AATCC 16-2003, GB/T 8427/8430, etc.

  • Cynthy Lee

    The machine looks good and I want to know more about it. Water-cooled Light & Weather Fastness Tester may be the best choice.

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