1. Key Test Methods

Chemical Dissolution Method (Chemical Dissolution Method)

This is the most commonly used method. Chemical reagents that dissolve only specific fibres are used, and the composition ratio is calculated by measuring the weight of the remaining fibres.

Microscopic Method (Microscopic Method)

• Application: This method is used when the dissolution method cannot be applied because the fibres have similar chemical properties, such as cashmere and wool, or when fibres have clear microscopic characteristics, such as cotton and linen.
• Method: The fibre cross-section or side profile is observed. The number of fibres is counted or the diameter is measured, and the volume ratio is converted into a mass ratio.
• Features: The analyst’s experience is highly important, and the distinctive morphological features of each fibre, such as wool scales and the natural twist of cotton, must be understood.

Quantitative Burning Test (Quantitative Burning Test)

• This is the most basic method, but it is used as a preliminary assessment when quickly checking whether a sample is a single fibre or a blend.
• The odour during burning, flame shape and ash form are observed. For example, cotton smells like burning paper and leaves grey ash, while polyester gives off a sweet odour and leaves a hard black residue.
• It is difficult to calculate an exact blend ratio by percentage using this method alone.

2. Advanced and Special Analysis Methods

FT-IR Spectroscopy (FT-IR Spectroscopy)

• This advanced method identifies fibre components by using the fact that each fibre molecule absorbs infrared wavelengths in different fingerprint regions.
• It can confirm components quickly without destroying the specimen and is highly effective for analysing coated fabrics and specially finished fibres.

DNA Barcoding (DNA Barcoding)

• This method has been introduced to determine authenticity and composition ratios for high-value animal fibres such as cashmere, yak and silk.
• DNA is extracted from fibre samples and compared with genetic information. It can detect differences between damaged wool and cashmere scales with an error margin of as little as 0.1%.

Solubility Sequence (Solubility Sequence)

This is a step-by-step dissolution method used when analysing complex blended products containing several fibre types, such as cotton, polyester, nylon and polyurethane. A single sample is placed sequentially in several reagents to remove each component one by one.

• Cyclohexanone: removes vinyl chloride-based fibres
• Acetone: removes acetate
• Formic acid: removes nylon
• 70% sulphuric acid: removes cotton and rayon
• Residue: confirms polyester

3. Testing Procedure (Standard Procedure)

4. Why Fiber Composition Testing Matters

• Consumer information: If the actual composition differs from the label, legal sanctions may apply. In many cases, an error margin of around 3% is permitted.
• Care instructions: Washing temperature and care methods can differ significantly depending on the material, making accurate composition information essential.
• Import and export duties: Tariff rates may be determined by the main fibre component, so accurate data is required.

Fiber composition testing is usually carried out strictly in accordance with KS K 0210, the test method for textile fibre composition, or ISO 1833.
For specific blended materials that require analysis, please contact us using the information below.