Question 21 (Textile Engineering & Fibre Science)
Bleached cotton fabric was sent to laboratory for determination of Copper Number, which is an estimate of the presence of
| (A) | Hydroxyl groups |
| (B) | Carboxyl groups |
| (C) | Reducing groups |
| (D) | Oxidizing groups |
Answer / Solution
[Show Answer]
Option C
Frequently Asked Questions | FAQs
What is copper number in textile?
Copper number is a term used in the textile industry to measure the concentration of substances, such as waxes, oils, and other impurities that can affect the performance and properties of textile fibers. It is a measure of the amount of copper ions that are released when a fiber is treated with a solution of copper sulfate.
The copper number test is a standard method used to evaluate the degree of purity of textile fibers. In this test, a small amount of the fiber is treated with a solution of copper sulfate, and the amount of copper ions released is measured using a spectrophotometer. The higher the copper number, the greater the concentration of impurities in the fiber.
The copper number is particularly important in the processing of textile fibers, such as cotton or wool. High levels of impurities can interfere with dyeing or other chemical treatments, affect the strength and durability of the fiber, and impact the overall quality of the final product. Therefore, the copper number test is an important quality control measure in the textile industry to ensure that fibers meet the required standards for purity and performance.
The determination of the copper number of a bleached fabric is a standard test in the textile industry that is used to measure the level of impurities, such as waxes, oils, and other substances, present in the fabric after the bleaching process. Here is a general overview of the procedure:
Sample preparation: Take a small sample of the bleached fabric and cut it into small pieces.
Copper sulfate solution preparation: Prepare a solution of copper sulfate by dissolving a specific amount of the compound in water. The exact concentration and volume of the solution depend on the test method and standards used.
Test procedure: Immerse the fabric samples into the copper sulfate solution for a specific period of time at a controlled temperature. After a given time, remove the samples and rinse them thoroughly with water to remove any excess copper ions.
Measure the copper number: Measure the amount of copper ions released from the fabric using a spectrophotometer or other analytical instruments. The result is expressed as the copper number, which is the amount of copper ions released per unit weight of the fabric.
The copper number test is an important quality control measure to ensure the purity and performance of the fabric. High levels of impurities can impact the strength, durability, and appearance of the fabric, and can also affect subsequent processing steps, such as dyeing or finishing.