Polyester-Viscose Blended Fabrics Disperse Dyeing Solution

Today, we're sharing a solution for high wash fastness of polyester-viscose blended fabrics with 180℃ high-temperature setting.

Our customer's fabric composition is 80% polyester/20% viscose. Previously, they had been using ordinary disperse black dyes, but in actual production, they encountered problems with substandard wash fastness. Simultaneously, the customer's process required 180℃ high-temperature setting after dyeing, and the six-fiber staining needed to reach level 4 or higher.

As is well known, controlling the fastness of polyester-viscose blended fabrics is extremely difficult, even more so than polyester-spandex blends, especially under high-temperature setting conditions. Most disperse dyes on the market struggle to simultaneously meet the requirements for wash fastness and heat migration.

Therefore, the customer brought fabric samples and their existing dyes to us, hoping we could provide a customized dye solution that could reliably pass 180℃ high-temperature setting.

Upon receiving the request, our engineers first conducted the initial testing using existing high-wash-fastness disperse dyes. The results showed that while the wash fastness was good after reduction washing, it significantly decreased after high-temperature setting at 180℃, exhibiting prominent heat migration, failing to meet the customer's actual production requirements.

As shown in the caption: The one on the right is a reductive wash followed by room temperature drying; its durability is excellent. A 180-degree settling will result in the shape shown on the left. Conclusion: The standard series has poor heat migration; a higher quality product is necessary.

Subsequently, the engineers tested our highest-grade high-wash SWF series disperse dyes. The engineers pointed out that the SWF series is a disperse dye system truly developed for high-wash and high-temperature setting processes, particularly suitable for polyester-viscose blended fabrics, maintaining excellent fastness performance even under 180℃ setting conditions.

After multiple rounds of sampling and process optimization, we ultimately recommended the following dye combination to the customer:

SWF-6GS Yellow

SWF-BFS Red

SWF-GSN Navy Blue

SWF-KSN Black

Experimental results showed that this combination maintained excellent wash fastness and six-fiber staining grade after high-temperature setting at 180℃, with all indicators consistently meeting or even exceeding the customer's requirements.

The customer was very satisfied after receiving our complete experimental report and data comparison. This solution not only successfully solved the long-standing problem of heat migration during high-temperature setting, but also helped customers effectively reduce dye and overall production costs thanks to its excellent cost-effectiveness, providing reliable and stable technical support for subsequent mass production.