Color Fastness to Perspiration, Light & Water | How to improve fastness properties of textile [বাংলা

COLOR FASTNESS TO PERSPIRATION TEST
The color fastness to perspiration test determines the resistance of textile colors to human perspiration.

Fabric dyes and human perspiration can often react and cause color fading in clothing items. A color fastness test for perspiration is particularly relevant for sports apparel and swimwear, which will most likely be exposed to heavy perspiration during use.

As we all know, the composition of human sweat is complex, the main component of which is salt, of which the amount varies from person to person. Sweat is acidic and alkaline. The short-term contact between textiles and sweat may have little effect on its Color Fastness, but long-term contact with the skin and sweat will have a greater impact on certain dyes. Clothing with unqualified Color Fastness is likely to cause dyes to transfer from textiles to human skin through sweat. The human body may absorb dye molecules and heavy metal ions through the skin, and this would endanger health.

Fastness to perspiration
The fastness of colored fabric with reference to alkaline and acidic perspiration was evaluated. For the alkaline (pH‐8) and acidic (pH‐5.5) liquors were prepared and the composite specimens were dipped in acidic and alkaline solution separately for 30 minutes. Good and uniform penetration of the solution was ensured. The liquor was poured off and the excess water and air bubbles, if any were removed by passing the specimens in between two glass rods. Composite specimens were then placed between glass/acrylic plates with a pressure of 12 kpa per spirometer.

The perspirometer, was kept for four hours at a temperature of 37 (±20C). Afterwards, the fabrics were removed, separated and dried in air below 60°C. The values were rated as per the grey scale.

The details of the values assigned for these properties are:
The values were rated as per the grey scale. The details of the values assigned for these properties are:-
 •5 =Negligible (Excellent)
 •4 =Slightly changed (Good)
 •3 =Noticeable changed (Fairly good)
 •2 =Considerably changed (Fair)
 •1 =Much changed (Poor)

Comparison of common standards of textile Color Fastness to Perspiration:
ISO 105 E04 and AATCC 15 are the two main standards for perspiration testing. For this test, the lab attaches a strip of multifiber fabric to the test specimen to measure staining. This multifiber fabric has swatches of different kinds of fibers, such as nylon, cotton, acetate, polyester, wool and acrylic fabrics.
The lab then compares the staining of the multifiber fabric to the Grey Scale for Staining, with a desired grade 3 rating. The lab compares the color of the test specimen with the Grey Scale for Color Change, with a desired grade 4 rating.
ISO 105 E04
During this test, the lab soaks the fabric in a simulated perspiration solution for 30 minutes under a fixed pressure and then dries it slowly at an elevated temperature.
ISO 105 E04 tests for color fastness to both acidic and alkaline perspiration. Human sweat is typically acidic, though it can become alkaline in higher temperatures or when bacteria are present.
AATCC 15
AATCC 15 only tests color fastness to acidic perspiration. The AATCC previously included alkaline test methods in the standard but removed it in 1974, as they didn’t believe it reflected normal end usage.
The drying time, pressure and temperature also vary between ISO 105 E04 and AATCC 15. AATCC 15 requires the fabric to be heated for longer at a slightly higher temperature than ISO 105 E04.
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How to improve the Color Fastness to perspiration? Examples of techniques for improving the Color Fastness of nylon fabric to perspiration


Factors influences colour fastness to perspiration:
• The influence of perspiration agent on the Color Fastness of nylon
• The influence of perspiration fastness agent and wet friction enhancer
• The influence of perspiration fastness agent and adhesive
• The influence of micro-polymerization of acrylic monomers
• The influence of monomer and Color Fastness additives on the Color Fastness of nylon fabric to perspiration
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COLOR FASTNESS TO WATER TEST
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COLOR FASTNESS TO LIGHT TEST
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How to improve the Color Fastness of textiles:
1. Selection of dyestuff
How fast a product is heavily dependent on the choice of dyestuff. If the choice of dyeing materials is inappropriate, no matter how good the auxiliary agent and the best dyeing process are, there is no way to dye high-quality Color Fastness. Only by choosing the right dye can we talk about the next step.

o Choose dyes according to fiber characteristics
o Choose dyes according to the color depth
o Select the dye according to its Color Fastness grade
o The dye uptake rate of the fiber
o There should be good compatibility between dyes

2. Selection and use of additives
o Choose suitable additives
o Minimize the amount of retarder
o Selection of fixing agent
o Soaping and washing
o Use of softener

3. Improvement in the dyeing and finishing process