Whitening Principle of Optical Brightener
Optical Brightening Agents (OBAs) are a class of functional chemicals that are widely used in the textile, paper, plastics, detergent and other industries. It enhances the whiteness and brightness of objects by absorbing ultraviolet light and emitting blue-violet fluorescence, thus improving the visual effect of products.
Optical Brightening Agents (OBAs) are a class of functional chemicals that are widely used in the textile, paper, plastics, detergent and other industries. It enhances the whiteness and brightness of objects by absorbing ultraviolet light and emitting blue-violet fluorescence, thus improving the visual effect of products.
Fluorescent whiteners cause molecules to enter an excited state by absorbing high-energy near-ultraviolet light. The excited molecules jump to a lower energy ground state and emit fluorescence. Due to the energy loss, the emitted fluorescence has a long wavelength, usually around 450nm of blue light. This blue light compensates for the yellowing of the surface of the object, thereby increasing the visual whiteness of the object. Since the intensity of the fluorescence is greater than the original intensity of the visible light on the surface of the object, a slightly bluish whitening effect is produced.
White objects usually absorb blue light in the visible light range of 450 to 480nm, which results in a weak blue color and produces a slight yellowish tint, making the item appear somewhat old. To solve this problem, Optical Brightening Agents (OBA) have been used. It absorbs ultraviolet light (in the wavelength range of 300 to 400nm) and emits visible blue-violet fluorescence (in the wavelength range of 420 to 480nm), which fills in the color difference due to the yellow tone of the item, giving the object a brighter white effect.
In brief, the whitening and color rendering principle of fluorescent whitening agent is divided into the following two parts:
1. Absorption and emission
The molecular structure of fluorescent whitening agent contains a conjugated system, which can absorb short-wave ultraviolet light energy, and release blue-violet fluorescence after electron jump.
2. Color compensation effect
The emitted blue-violet fluorescence is superimposed on the reflected light of the material, which compensates for the original yellow or grayish hue of the material, making it look whiter and brighter.
Ogilvy chemical specializes in whitening and coloring, and is a veteran supplier with more than 20 years of experience. If you have whitening needs, welcome to contact us! Whether you are whitening recycled plastics, whitening virgin plastics PVC, whitening PET, whitening soap detergents, etc., we can provide you with the most environmentally friendly and affordable solutions!
