Wool, as a natural protein fiber, has a unique scale structure and physicochemical properties on its surface, which necessitates the use of targeted specialized auxiliaries to improve quality and overcome inherent drawbacks.

I. Core Finishing Objectives and Corresponding Auxiliaries
The selection of auxiliaries for wool fabrics should revolve around four core finishing needs:
1. Anti-shrinkage and anti-pilling finishing agents:
This is the most important aspect of wool finishing. Resin-type polymers (such as polyurethane and polyacrylate) or special organosilicon elastomers are mainly used. They form a flexible thin film on the fiber surface, effectively bonding the scales, significantly reducing felting shrinkage caused by the directional friction effect (D.F.E.) of the scales, and improving anti-pilling performance.
2. Softening and smoothing finishing agents:
Given that wool itself tends to be stiff or even itchy, amino-modified organosilicon microemulsions or ultra-smooth silicone oils should be selected. They can penetrate deep into the fibers, providing excellent softness and smoothness, significantly improving skin comfort and eliminating itchiness. It is important to choose products compatible with the weakly acidic environment of wool.
3. Easy-care and anti-wrinkle finishing agents:
To improve the daily practicality of wool fabrics, special anti-wrinkle resins for wool should be used. They can establish elastic cross-links between fiber molecules, improving the dimensional stability of the fabric, making clothing easier to care for and less prone to wrinkling.

II. Functional and Environmentally Friendly Auxiliaries
1. Special functional finishing agents:
Depending on the end use, the following can be selected:
Water and oil repellent agents: Fluorine-containing or modified organosilicon products, providing protective functions for wool coats and outdoor clothing.
Flame retardants: For wool fabrics used in interior decoration or protective clothing that meet specific regulatory requirements.
Antibacterial and mothproof agents: Protecting wool fibers from moth damage and adding hygienic functions.
2. Environmentally friendly and processing auxiliaries:
Low-temperature dyeing auxiliaries: Used in the dyeing process, they promote dye uptake, facilitating low-temperature dyeing, saving energy and reducing damage to wool fibers. Enzyme preparations: For example, proteases can be used for wool weight reduction or surface finishing, representing an environmentally friendly processing option.

III. Selection Principles and Precautions
1. Synergy and Sequence: When using multiple auxiliaries in the same bath, their ionic compatibility must be strictly verified. The finishing process usually follows the principle of "functionality first, then hand feel."
2. Process Adaptability: The selected auxiliaries must match the conventional processing conditions of wool (such as weakly acidic pH and medium temperature treatment), avoiding fiber damage caused by strong alkalis or prolonged high temperatures.
3. Regulatory Compliance:  Especially for export products, it is necessary to ensure that the selected auxiliary components comply with international environmental regulations (such as OEKO-TEX® STANDARD 100, REACH).

Conclusion: The selection of auxiliaries for wool fabrics is a precise science, with the core principles being "targeted protection" (shrinkage prevention) and "refined modification" (softening). The modern trend is to develop multi-functional, environmentally friendly, and low-temperature processing composite auxiliaries, comprehensively improving the performance of wool fabrics while maximizing the protection of their natural and noble qualities.