Fibre Price per Kilo Translated into Cost per Finished Metre
Translating fibre price per kilo into cost per finished metre requires adjusting raw cost for commercial regain, spinning yields, weaving crimp, finishing shrink, and customs tariffs.
ISO 1833 Quantitative Fibre Analysis
Blend Composition Testing
Chemical procedures for separating and weighing different fibre types within a blended textile provide an accurate breakdown of the material components. The iso 1833 quantitative fibre analysis standard uses selective dissolution to remove one component of a blend while leaving the other intact. It is the primary method for verifying label claims such as sixty percent cotton and forty percent polyester.
Results are expressed as a percentage of the total dry mass of the specimen.
Chemical Method
Technicians choose specific solvents based on the fibres present in the sample. For a cotton and polyester blend, concentrated sulphuric acid is used to dissolve the cotton, leaving the polyester fibres behind for weighing. The process requires precise temperature control and specific immersion times to ensure complete separation without damaging the insoluble component.
After the reaction, the remaining fibre is washed, dried and weighed to calculate the proportions. This method is repeated for each fibre type in more complex blends containing three or more materials.
Regulatory Compliance
Global labelling laws mandate that the fibre content stated on a garment tag must be accurate within a small tolerance. The data generated by the iso 1833 quantitative fibre analysis allows manufacturers to prove their products comply with these legal requirements. Customs authorities and consumer protection agencies use this test to check for fraudulent claims or the presence of undeclared fibres.
Because some fibres are much more expensive than others, accurate analysis prevents the sale of lower-quality goods as premium items. This verification builds trust between the brand and the end consumer.
Specimen Preparation
Samples must be cleaned of all non-fibrous matter before the chemical analysis begins. Natural fats and synthetic finishes are removed through a pre-treatment process using petroleum ether or water. This step ensures that the measured weight reflects only the fibres themselves.
Proper preparation is essential for accuracy.