Question 41 (Textile Engineering & Fibre Science)
Consider the elements in Group I and the corresponding monomer(s) in Group II. Choose the correct alternative from amongst A, B, C and D
|Group I||Group II|
|P||Resin finishing||1||Polyester dyeing|
|S||Discharge printing||4||Hydrogen peroxide|
|6||Sodium sulphoxylate formaldehyde|
|(A)||P-3, Q-1, R-2, S-6|
|(B)||P-6, Q-1, R-4, S-3|
|(C)||P-3, Q-6, R-1, S-5|
|(D)||P-3, Q-6, R-4, S-1|
Option A is correct.
Frequently Asked Questions | FAQs
What are the benefits of resin finishing?
Resin finishing, also known as resin treatment or resin coating, is a textile finishing process that involves applying synthetic resin substances to the fabric surface. This treatment offers several benefits and can enhance the performance, appearance, and durability of the fabric. Here are some of the benefits of resin finishing:
Wrinkle Resistance: Resin finishing can impart wrinkle resistance to fabrics, reducing the formation of creases and wrinkles during use or storage. The resin forms a thin, flexible film on the fabric surface, which helps the fabric retain its smooth appearance for longer periods, requiring less ironing or pressing.
Dimensional Stability: Fabrics treated with resin finishing are more resistant to dimensional changes caused by stretching, tension, or repeated laundering. The resin coating helps stabilize the fabric structure, reducing shrinkage and ensuring that the fabric retains its original shape and size.
Durability: Resin finishing can improve the durability and abrasion resistance of fabrics. The resin coating creates a protective layer that shields the fabric fibers from wear and tear, increasing the fabric’s lifespan and making it more resistant to fraying, pilling, and damage.
Water and Stain Resistance: Resin finishing can provide water repellency and stain resistance to fabrics. The resin coating creates a barrier that prevents water or liquids from penetrating the fabric, allowing them to bead up and roll off the surface. This property helps keep the fabric dry and prevents stains from setting in, making it easier to clean.
Enhanced Print Clarity: Resin finishing can enhance the clarity and sharpness of printed designs on fabrics. The resin coating creates a smooth and uniform surface, reducing the absorption and spread of ink, resulting in vibrant and well-defined prints.
Improved Drapability: Resin finishing can modify the hand or feel of the fabric, making it softer and more pliable. It can enhance the drape and flow of the fabric, giving it a more pleasing and luxurious appearance.
Special Effects: Resin finishing allows for the incorporation of special effects in fabrics, such as glossy or matte finishes, embossed textures, or even three-dimensional effects. These effects can add visual interest and uniqueness to the fabric, making it suitable for various fashion and decorative applications.
It’s important to note that the specific benefits achieved through resin finishing can vary depending on the type of resin used, the application method, and the fabric composition. Additionally, resin finishes may have certain limitations, such as reduced breathability or a potential impact on the natural feel of the fabric. Therefore, it is crucial to consider the specific requirements and characteristics of the fabric and the intended end-use when considering resin finishing as a textile treatment.
What are carriers in dyeing?
In dyeing processes, carriers are auxiliary substances used to facilitate the application and fixation of dyes onto the fabric. They are typically organic compounds that help overcome limitations in dye solubility, improve dye penetration, enhance color yield, and promote uniform dye distribution. Carriers play a crucial role in certain dyeing methods, particularly for dyeing synthetic fibers like polyester.
Here are some key functions and benefits of carriers in dyeing:
Solubilization: Carriers are used to solubilize and disperse dyes that have poor solubility in water or the dye bath. They act as a carrier medium for the dye, allowing it to dissolve and distribute evenly in the dye bath. This ensures that the dye can be applied effectively to the fabric.
Dye Penetration: Carriers aid in the penetration of dyes into the fiber structure, particularly for hydrophobic synthetic fibers like polyester. They enhance the wetting properties of the dye solution, allowing it to permeate the fiber surface more easily. This improves the dye’s ability to migrate into the fiber and achieve deeper coloration.
Leveling and Dye Migration: Carriers promote leveling, which refers to the even distribution of dye on the fabric surface. They assist in controlling and reducing dye migration during the dyeing process. This helps prevent uneven dyeing and ensures consistent color throughout the fabric.
Color Yield and Intensity: Carriers can enhance the color yield and intensity of dyes. They improve the affinity of the dye for the fiber, leading to better dye fixation and increased color depth. This allows for vibrant and saturated color results.
Temperature Control: Carriers often have a higher boiling point than water, which enables dyeing at elevated temperatures. This is particularly useful in dyeing processes that require high temperatures, such as disperse dyeing of polyester. Carriers help maintain the stability and solubility of the dye bath at these elevated temperatures.
Reduced Staining and Ringing: Carriers can minimize staining or ringing effects, which occur when excess dye deposits unevenly on the fabric surface. They aid in preventing the formation of concentration gradients and assist in the uniform distribution of dye, resulting in more consistent and controlled dyeing.
It’s important to note that the use of carriers is specific to certain dye types and dyeing methods, especially when working with synthetic fibers. The choice of carrier and its concentration depends on the specific dyeing process, dye type, fiber composition, and desired results.
What is bio polishing?
Bio polishing, also known as enzymatic or bio-enzymatic treatment, is a textile finishing process that uses enzymes to improve the appearance and performance of fabrics, particularly those made from cotton or other cellulosic fibers. It involves the controlled degradation of the fabric’s surface to remove fuzz, pills, and other imperfections, resulting in a smoother and more refined fabric. Bio polishing is commonly used in the textile industry to enhance the quality and handle of fabrics.
Here’s an overview of the bio polishing process and its benefits:
Enzyme Treatment: Bio polishing involves the application of specific enzymes, typically cellulases, onto the fabric. These enzymes break down and remove the protruding fibers, such as fuzz and pills, that are present on the fabric surface. Cellulases are particularly effective as they target the cellulose fibers in the fabric while being gentle on the fabric itself.
Surface Smoothing: The enzymatic action of bio polishing causes the removal of microfibers and irregularities from the fabric surface. This leads to a smoother and more even fabric appearance, reducing the presence of fuzz, lint, and pills that can give the fabric a worn or aged look.
Improved Softness and Handle: Bio polishing enhances the softness and hand feel of the fabric. By removing the protruding fibers and irregularities, the fabric becomes smoother and has a more luxurious and comfortable touch. This is especially desirable for fabrics intended for garments or textiles that come into direct contact with the skin.
Enhanced Color Brilliance: Bio polishing can also enhance the color brilliance of the fabric. By removing the surface fuzz and lint, the fabric surface becomes cleaner and reflects light more evenly. This results in improved color perception, making the fabric appear brighter and more vibrant.
Pilling Prevention: Bio polishing helps prevent pilling, which is the formation of small, tangled balls of fiber on the fabric surface. By removing the loose fibers that can cause pilling, the fabric becomes more resistant to the formation of these unsightly and unwanted pills, thereby maintaining its visual appeal for a longer time.
Durability and Longevity: Bio polishing can improve the fabric’s durability and longevity. By removing weak and loose fibers, the fabric becomes more resistant to abrasion, wear, and tear. This can prolong the life of the fabric, allowing it to retain its appearance and quality even after repeated use and laundering.
Eco-Friendly Alternative: Bio polishing is considered an environmentally friendly alternative to traditional fabric treatments. Enzymes used in bio polishing are biodegradable and do not pose significant harm to the environment. Additionally, the process typically requires less water and energy compared to other textile finishing techniques.
Bio polishing is commonly applied to cotton fabrics, such as t-shirts, knits, and denim, as well as other cellulosic fibers. It is a popular choice for achieving a smooth and refined fabric surface with improved softness, color brilliance, and overall quality.
What chemicals are used in discharge printing?
Discharge printing is a fabric printing technique that involves the removal of color from dyed fabric to create patterns or designs. It utilizes specific chemicals known as discharge agents or discharge pastes to achieve the desired effect. The primary chemicals used in discharge printing include:
Discharge Agent: The discharge agent is the main chemical used in the process. It typically contains a reducing agent, such as thiourea dioxide or sodium bisulfite, which acts as a bleach to remove or reduce the existing color from the fabric. The discharge agent breaks down the dye molecules, making them soluble and removable during the subsequent washing or rinsing steps.
Thickening Agents: Thickening agents are used to give the discharge paste the desired consistency for printing. These agents help control the viscosity and prevent the discharge agent from spreading or bleeding excessively on the fabric. Common thickening agents include sodium alginate, guar gum, or other suitable natural or synthetic thickeners.
Catalysts or Activators: Catalysts or activators are additives that help initiate and accelerate the chemical reaction between the discharge agent and the fabric dye. They enhance the bleaching effect and promote color removal. Common catalysts used in discharge printing include zinc formaldehyde sulfoxylate or other suitable compounds.
Stabilizers: Stabilizers are sometimes added to the discharge paste to improve its stability and prevent premature reaction or breakdown of the discharge agent. These compounds help maintain the effectiveness of the discharge paste during storage and printing.
Printing Medium: The discharge paste needs to be compatible with the printing technique being used. Depending on the specific printing method, the discharge agent and other chemicals are mixed with a suitable printing medium or binder. The printing medium helps bind the discharge paste to the fabric during printing, ensuring proper adhesion and color removal.
It’s important to note that discharge printing involves the use of chemicals that can be hazardous if not handled properly. Safety precautions should be followed, such as using protective equipment, proper ventilation, and adhering to appropriate handling and disposal procedures, to ensure the safety of workers and the environment.
The specific composition and formulation of discharge agents may vary depending on factors such as the type of fabric, desired color removal effect, and printing method. It is recommended to consult with chemical suppliers or experts in discharge printing for guidance on the appropriate chemicals and procedures for a specific application.