Question 46 (Textile Engineering & Fibre Science)
Consider the following Assertion [a] and Reason [r]
[a] In the case of durable press finishing of cotton fabrics, while the citric acid can be used as a crosslinking agent, oxalic acid cannot be.
[r] The mechanism of crosslinking requires formation of anhydride in the intermediate step .
Determine the correctness or otherwise of the above Assertion [a] and Reason [r]
|(A)||[a] is right [r] is wrong|
|(B)||[a] is right [r] is right|
|(C)||[a] is wrong [r] is right|
|(D)||[a] is wrong [r] is wrong|
Answer / Solution
Frequently Asked Questions | FAQs
What is a durable press finish on cotton?
A durable press finish on cotton is a chemical treatment applied to the fabric that improves its wrinkle resistance and crease retention. The treatment involves the application of a resin or polymer that is cured onto the fabric using heat, pressure, and sometimes a catalyst. The resulting fabric has improved shape retention, is less likely to wrinkle, and requires less ironing.
The use of durable press finishes is common in clothing and home textiles, particularly in cotton and cotton-blend fabrics. It is especially useful for items such as dress shirts, where a crisp, wrinkle-free appearance is desired. The treatment also extends the life of the fabric by reducing the need for frequent washing and ironing, which can weaken the fibers and cause shrinkage.
However, the use of durable press finishes can have some drawbacks. The chemicals used in the treatment can cause skin irritation or allergic reactions in some people. Additionally, the treatment can affect the texture and hand-feel of the fabric, making it stiffer and less breathable. Some people also find that the finish gives off a chemical odor, particularly when the fabric is new.
Overall, the use of a durable press finish on cotton can be a useful option for those who want the convenience of wrinkle-resistant clothing or home textiles, but it is important to consider the potential trade-offs in terms of comfort and environmental impact.
How can durable press finish characteristics be imparted to cotton materials?
Durable press characteristics can be imparted to cotton materials through the use of chemical treatments. The most common way to achieve durable press in cotton is through the application of a resin or polymer that is cured onto the fabric using heat and pressure.
Here are the steps involved in imparting durable press characteristics to cotton materials:
Preparation: The cotton fabric is washed and dried to remove any dirt or impurities that may interfere with the application of the resin.
Application: The resin or polymer is applied to the fabric using a variety of methods, such as padding, spraying, or foaming. The fabric is then dried to remove any excess moisture.
Curing: The fabric is cured under heat and pressure to activate the resin and bind it to the cotton fibers. This step is usually done in a press, where the fabric is sandwiched between two heated plates and subjected to pressure and heat for a specific period of time.
Post-curing: Some durable press treatments require a post-curing step, which involves subjecting the fabric to additional heat and pressure to further activate the resin and improve the durability of the finish.
Finishing: After the curing and post-curing steps, the fabric is finished using a variety of techniques, such as calendaring or brushing, to achieve the desired texture and appearance.
The specific chemicals and processes used to achieve durable press in cotton can vary depending on the desired characteristics of the finished product. Some treatments may also include other chemical additives, such as cross-linking agents or catalysts, to enhance the durability of the finish.
It’s important to note that while durable press finishes can be beneficial for certain applications, they do have some drawbacks. The use of chemical treatments can affect the texture and hand-feel of the fabric, and may also have environmental and health implications. As such, it’s important to weigh the benefits and trade-offs of durable press finishes when considering their use in cotton materials.