Dec. 17, 2019
1. Brightening effect of Fluorescent Brightener For Detergent
The whitening effect is often expressed by whiteness. In addition to the amount of fluorescent whitening agent added, it is also related to the compatibility of the resin and the light resistance of the plastic. The fluorescent whitening agent with good compatibility and good light resistance has good whitening effect and lasting. A direct and effective way to verify the whitening effect of fluorescent brighteners is to conduct a sample experiment.
2. The amount of fluorescent whitening agent
The amount of fluorescent whitening agent is usually expressed as a percentage relative to the mass of the plastic. The amount of optical brightener in plastic is related to its chemical structure, dispersion, and the properties of plasticizers or other additives in plastic formulations. The amount of fluorescent whitening agent is generally from 0.05% to 0.1% (for plastic), and for ultra-white varieties, the amount can reach 0.5% (for plastic) or more. Appropriate dosage should be determined by sample test to meet the requirements of the application. It is not that the more the amount of fluorescent whitening agent is used, the better the whitening effect, but there is a certain concentration limit that exceeds a certain limit , Not only does not have a whitening effect, and even yellowing occurs. Excessive amount of fluorescent whitening agent will also cause incompatibility, migration phenomenon, and degradation of anti-aging performance.
Using two or more different fluorescent brighteners, if selected properly, the fluorescence spectrum will be broadened, and its fluorescence intensity will be enhanced to achieve the purpose of synergism and improve its application performance.
3. The effect of pigments in plastic formula on whitening effect
Because the role of the fluorescent whitening agent is to convert ultraviolet light into visible blue or purple light, the components that have a greater impact on the fluorescent whitening agent itself are those that can absorb ultraviolet light, that is, white pigments and ultraviolet light stabilizers. Titanium dioxide in white pigments can absorb the 380nm light wave in ultraviolet light. If it is present in plastic products, it will reduce the whitening effect of fluorescent whitening agents. Due to the different absorption of 380nm light waves of different crystal types of titanium dioxide, the anatase type can only absorb 40% of 380nm light; the rutile type can absorb 90%. If titanium dioxide is used in combination with a fluorescent brightener, anatase Type titanium dioxide and appropriately increase the amount of fluorescent brightener. For plastics, a professional Optical Brightener Agent For Plastic should be used.
Optical Brightener Agent For Plastic
White pigments vary according to how much they absorb ultraviolet light. The ultraviolet light in the area that works for most fluorescent brighteners is also absorbed by the anatase and rutile titanium dioxide. The zinc sulfate has a slightly lower absorption capacity for this part of the ultraviolet light. This difference is apparent in molded articles colored with a white pigment containing a fluorescent whitening agent. At the same concentration of the fluorescent whitening agent, generally speaking, the whiteness reached when zinc sulfate is used is strong, and the whiteness is weaker when rutile titanium dioxide is used. Under certain conditions, the use of rutile pigments cannot significantly increase the degree of whiteness. If whiteness needs to be increased, the concentration of fluorescent whitening agent should be increased. For example, in a polyethylene formulation, a white effect can be obtained immediately with 2.0% rutile pigment and 0.2% optical brightener, or 5% anatase pigment and 0.05% optical brightener.
The above are the precautions for the use of fluorescent brightener introduced by Fluorescent Brightener Agent Supplier. I hope to help you.