Optical brightener NFW

Optical brightener NFW/NFW-L is a multifunctional whitening agent mainly used in the textile industry. It is a yellow-green powder, anionic, and its chemical structure is a stilbene derivative. It has a purplish color and is very similar to products like Huntsman's Uvitex NFW.

Main features:
1. High affinity for specific fibers
- The optical brightener NFW/NFW-L has a low affinity for cellulosic fibers such as cotton, but a strong affinity for wool and nylon fibers. Therefore, it is very effective on fabrics made from these materials.
2. High fluorescence intensity
- This product has a bright whiteness and purplish tint that enhances the overall appearance of treated fabrics. The high fluorescent intensity ensures that the fabric retains its brightness for a long time.
3. Good stability over the entire pH range
- The optical brighteners NFW/NFW-L are stable over a wide pH range from 2 to 12 and are therefore suitable for a wide range of dyeing processes. It maintains efficacy even in acidic or alkaline conditions, ensuring consistent results.
4. Compatibility with bleach
- This product is very stable when used with sodium hydroxide and hydrogen peroxide, which are commonly used in textile processing. However, when exposed to sodium chlorite and sodium hypochlorite, its stability is poor, which may affect its performance.

Product application:
1. Nylon and cotton fabrics
- Fluorescent whitening agent NFW/NFW-L is suitable for exhaust dyeing and continuous pad dyeing processes, especially for nylon and cotton fabrics. Although it has a lower affinity for cellulosic fibers, it can still be used effectively on cotton fabrics when mixed with nylon.
2. Wool and silk fabrics
- The additive is also very effective when treating wool and silk fabrics and its high affinity enhances the whitening effect. This application is particularly beneficial for luxury textiles to achieve vivid and bright colors.
3. Wide application in textile dyeing
- The product's adaptability to a variety of textile materials makes it ideal for manufacturers seeking brightness and whiteness in their products. This brightener has a wide range of applications and can be used on a variety of textile types and dyeing methods.

How to use:
1. Nylon and cotton treatment
- After reduction bleaching treatment, use optical brightener NFW/NFW-L at a dosage of 0.1-0.5% by weight of the fabric (o.w.f). The addition amount of sodium sulfate is 2-5g/L, and the liquid ratio is 1:10-20. Treatment temperature range is 80-100°C and time is 30-60 minutes.

2. Wool and Silk Treatment
- For wool and silk, this agent should be used after peroxide bleaching and reduction bleaching. Recommended dosage is 0.1-0.3% (o.w.f), adjust pH to 4-6 with acetic acid. The liquid ratio was maintained at 1:10-20, the temperature was set between 60-100°C, and the time was 20-60 minutes.

Things to note:
1. Temperature and electrolyte sensitivity
- The affinity of the product is closely related to the temperature and electrolyte content in the dye bath. To obtain ideal whitening results, these parameters must be carefully controlled.
2. Limited use of cellulosic fibers
- While the optical brightener NFW/NFW-L is very effective on wool, silk and nylon, its use on cellulosic fibers such as cotton is more limited. Manufacturers should take this into consideration when planning their dyeing process.
3. Water solubility
- This additive has good water solubility and requires only a small amount of warm water to dissolve completely, making it easy to operate during preparation and use.
4. Compatibility with acid dyes
- When adjusting the shade of fabrics, it is recommended to use acid dyes together with the optical brightener NFW/NFW-L to achieve the desired shade and brightness.
5. High temperature washing
- If the processed fabric requires high-temperature washing, it is recommended to add electrolytes during the washing process to maintain the whiteness and brightness given to the fabric by the whitening agent.
6. Sodium chlorite bleaching
- Sodium chlorite bleaching can remove the optical brightener NFW/NFW-L from cellulose and nylon fabrics, which may be necessary at certain post-processing stages.