oba for cotton

Oba(optical brightening agent) for cotton are mostly powdery, generally light yellow in appearance, anionic, easily soluble in water, and the solution is slightly yellow, fluorescent, and neutral. It can be absorbed by the fiber in the aqueous solution, has excellent leveling and permeability, can directly dye the fiber, and is convenient to use.

Generally, anionic oba(fluorescent whitening agents) can be alkali-resistant to pH=10~11, and the range of acid resistance is not the same, and they cannot be used in the same bath with cationic dyes and additives. Too high water hardness will also reduce the whitening effect. Some acid-resistant  optical brightening agents can be used for whitening cotton in the same bath with resin finishing agents.

The dosage of cotton cloth dip-dyeing optical brightening agents is 0.1%~0.3%, and the drying temperature is 90-100℃. If the whitened fabric is stacked in a wet state for more than 0.5h, then it is dried at a lower temperature or in a cool place. Dry it for better whitening effect.

Pad dyeing and whitening fabrics usually need to be scoured, bleached, dechlorinated, and dried. The dye liquor should be controlled in neutral or slightly alkaline. The dosage of optical brightening agents is 1-2g/L.

For sizing and whitening bleached fabrics or dark-colored fabrics with white patterns, optical brightening agents can be added to the finishing pulp, and the dosage is generally 1~2g/L.

Soap bath for whitening and brightening. After treatment, wash with water and dry. The amount of optical brightening agents is 50g, bath ratio is 1:15, and treatment is at 80°C for 6 minutes.

The addition of optical brightening agents to the whitening printing paste can make the whiteness of the white pattern more vivid. Generally, the optical brightening agents is fully dissolved in hot water before slurry preparation, and after cooling, it is quickly transferred into the prepared printing slurry under stirring. , The addition amount of optical brightener is 3~5g/L.

Optical brightening agents can also be added to the anti-whitening printing paste for whitening, the dosage is about 2-4g/L.

Light-colored fabrics are brightened. For light-colored fabrics such as general variegated poplin, optical brightening agents can be added to brighten the final finishing. The dosage is about 1g/L. The brightness and brightness of the late treatment increase, and the color changes.

Optical brightening agents used in cotton textiles include CXT CBS-X VBL BA BBU MAST-L NFW and so on.