Question

The trilobal cross section of polyester is observed in

• A. Cotton
• B. Wool
• C. Silk
• D. Jute

Hint:

• Polyester is a synthetic fiber; its cross-sectional shape can be modified.
• A trilobal cross-section in polyester enhances luster, soil-hiding, and can improve handle and comfort.
• Silk} naturally has a somewhat triangular or rounded-triangular cross-section, which contributes significantly to its characteristic luster and shimmer.
• Modified polyester cross-sections (like trilobal) are often engineered to mimic desirable properties of natural fibers, particularly silk's appearance.

Answer 1

The Correct Option is C

To determine which fiber—Cotton, Wool, Silk, or Jute—has the trilobal cross-section of polyester, let’s break down the concept and solution in detail.

What is a Trilobal Cross Section?

The trilobal cross section refers to the shape of the fiber's cross-section. It resembles a triangular or three-lobed shape, which can be observed in some synthetic fibers, such as polyester. This cross-sectional shape is designed to enhance the fiber's properties, such as its luster, moisture-wicking ability, and durability.

Now, let’s analyze each fiber listed in the options and examine their characteristics:

1. Cotton

• Type: Natural, plant-based (cellulosic) fiber.
• Structure: Cotton fibers are cylindrical in shape and do not have a trilobal cross-section.
• Why?: Cotton’s structure is purely round, with a natural hollow in the center, which helps with moisture absorption but does not feature the trilobal cross-section seen in synthetic fibers like polyester.

2. Wool

• Type: Natural, animal-based (protein) fiber.
• Structure: Wool fibers have a scaly structure and are generally round in shape. They do not exhibit a trilobal cross-section.
• Why?: Wool fibers are made up of overlapping scales that help trap air and provide insulation, but they do not have the trilobal cross-section characteristic of polyester fibers.

3. Silk

• Type: Natural, animal-based (protein) fiber.
• Structure: Silk fibers, though primarily cylindrical, can sometimes exhibit a triangular or trilobal cross-section depending on the manufacturing process.
• Why?: Although silk is naturally smooth and round, some processed silk fibers are created with a trilobal cross-section, especially in commercial textile manufacturing, to enhance luster and improve fabric properties. This makes silk the correct answer in this context.

4. Jute

• Type: Natural, plant-based (cellulosic) fiber.
• Structure: Jute fibers are cylindrical and have a rough texture. They do not exhibit a trilobal cross-section.
• Why?: Jute’s fibers are coarse and have a simple cylindrical shape, which makes them suitable for industrial applications like sacks but not for the sleek properties of trilobal fibers.

Why Does Silk Have a Trilobal Cross Section?

Silk fibers, particularly those modified for textile use, are sometimes manufactured with a trilobal cross-section. This process is used to improve the fiber's appearance, giving it extra luster and shine. The trilobal shape also enhances the fiber's moisture-wicking properties, making it an excellent choice for high-quality fabrics.

Final Answer

The fiber with the trilobal cross-section, among the options, is Silk.