Problems and Dyeing Challenges in CVC, PC, and TC Blended Fabrics

In the textile industry, professionals often face technical questions during viva or job interviews — especially about blended fabrics like CVC, PC, and TC. These topics can be confusing if the basic concepts of mixing and blending are not well understood.

Let’s discuss these topics step by step.

 

🔹 Difference Between Mixing and Blending

Mixing:
When different grades of the same type of fiber are combined, it is called mixing.
👉 Example: 50% cotton fiber of 1.125" staple length + 50% cotton fiber of 1.25" staple length.
Here both are cotton fibers — only their grades differ. Hence, it is mixing.

Blending:
When two or more different types of fibers (such as cotton and polyester) are combined, it is called blending.
👉 Example: 60% cotton + 40% polyester (CVC) or 65% polyester + 35% cotton (PC/TC).

🧵 Mixing is usually done in the Blow Room, while Blending is done on the Draw Frame machine.

 

🔸 What Are CVC, PC, and TC Fabrics?

1. CVC (Chief Value of Cotton):
CVC fabric is a cotton-polyester blend where cotton content is higher than polyester.
👉 Example: 65/35 CVC = 65% cotton + 35% polyester.
This fabric combines the softness and comfort of cotton with the strength and wrinkle resistance of polyester.

2. PC (Poly-Cotton):
In PC fabric, polyester content is higher than cotton.
👉 Example: 80/20 PC = 80% polyester + 20% cotton.
PC fabrics are more durable and affordable but slightly less comfortable than cotton-rich fabrics.

3. TC (Tetron-Cotton):
TC is another name for PC fabric — where Tetron (a Japanese name for polyester) is used instead of “polyester.”
So, TC = Tetron + Cotton = Polyester + Cotton blend, with higher polyester content.

 

🔹 Why Is CVC Fabric Preferred Over 100% Cotton?

While pure cotton fabrics are soft, breathable, and absorbent, they also have a few disadvantages:

• Prone to wrinkles easily
• Require frequent ironing
• More expensive than blended options

On the other hand, CVC fabrics offer several advantages:

• Lower cost
• Higher durability
• Better wrinkle resistance (thanks to polyester)
• Improved moisture absorption (thanks to cotton)
  Thus, CVC combines the comfort of cotton and the strength of polyester — making it more practical for daily wear and industrial use.

 

🔸 Dyeing of CVC and Blended Fabrics

Dyeing blended fabrics like CVC, PC, or TC is more complex than dyeing pure cotton or polyester because each fiber type reacts differently to dyes and heat.

✅ Single-Part and Double-Part Dyeing:

• Single-Part Dyeing: Only one dyeing process is done, usually for lighter shades or when both fibers are dyed with compatible colors.
• Double-Part Dyeing: Both parts are dyed separately:
• Polyester part → Disperse dye (at 130–140°C)
• Cotton part → Reactive dye (at 40–60°C)

After polyester dyeing, the fabric undergoes reduction clearing before cotton dyeing.

✅ Dyeing Temperature:

• Polyester fibers are highly crystalline, requiring 130–140°C for proper dye fixation.
• Cotton fibers have both amorphous and crystalline regions and fix color around 60–80°C.
  That’s why polyester is dyed first at high temperature using HTHP (High Temperature High Pressure) Winch Dyeing Machines, followed by cotton dyeing in atmospheric winch machines.

 

🔹 Shade Matching in Blended Fabric Dyeing

Shade matching is a critical step in blended fabric dyeing.
The final shade is usually adjusted during the cotton dyeing stage.
If cotton is dyed first and then polyester, the high temperature required for polyester dyeing would cause color migration or loss from the cotton part.
Hence, polyester is always dyed first, followed by cotton.

 

✅ Conclusion

By now, you should have a clear understanding of mixing, blending, and the dyeing process of CVC, PC, and TC blended fabrics.
Blended fabrics are widely used in the textile industry because they combine comfort, durability, and cost efficiency.
Understanding their structure and dyeing process is essential for textile engineers and dyeing professionals.