Application Of Pigment Carbon Black

Application of UV protection

One of the uses of carbon black in the plastics industry is to prevent ultraviolet light aging. Because carbon black has high light absorption, it can effectively prevent the plastic from being irradiated by the sun to produce photo-oxidative degradation. The role of carbon black as a UV stabilizer in plastics includes: converting light energy into heat; protecting the plastic surface from radiation of a certain wavelength; intercepting atomic groups to produce anti-aging effects, thereby preventing catalytic degradation. Ultraviolet rays are particularly harmful to polyolefins. Tests have shown that when the concentration of a certain fineness of carbon black is 2%, a perfect UV shielding effect can be achieved.

The protective effect of carbon black on the UV aging of plastics depends on the particle size, structure and surface chemistry of carbon black.

When the particle size of carbon black is small, due to the increased surface area, its ability to absorb light or shading increases, so the UV protection effect is enhanced, but the particle size is less than 20nm, and its protection effect tends to the same level. The reason is that when the particle size is too small, the reverse The scattering is reduced, and the light that continues forward threatens the stability of the polymer.

The structure is lower, that is, when the size of the aggregate is small, because the geometric volume of the aggregate is smaller, the protective effect on the polymer will be enhanced. This is also the reason why the carbon black with a lower structure is darker.

Carbon black has more oxygen-containing groups on the surface, that is, when the volatile content is higher, it can eliminate the genes generated when the polymer is decomposed, so the protective effect is also enhanced.

Injection masterbatch is divided into advanced and ordinary type

High-grade masterbatch is mainly used in cosmetic packaging boxes, ABS for automobiles, high-grade PVC synthetic leather, housings of household appliances and other high-grade products. It requires the color masterbatch to use the pigment to be evenly dispersed, especially for coloring products without color spots and stains. Carbon black should be pigmented carbon black with small particle size and low structure, because the blackness is mainly based on the absorption of light, the smaller the particle size, the higher the light absorption, the weaker the light reflection, the higher the blackness, and the product is generally dark black. bright.

Ordinary masterbatch is mainly used for PE garbage bags, cables, pipes and other products. Advanced films require small pigment particles and uniform dispersion. There should not be a color point greater than 0.6mm on the film. Common films can be used with larger particle sizes. , Ordinary pigment carbon black with higher structure, medium blackness and better dispersibility can be used.

The fiber masterbatch is mainly divided into polypropylene and polyester. Mainly used in chemical fiber silk, carpets, non-woven fabrics, etc. Carbon black is required to contain high purity, good dispersibility, high tinting power, no impurities, and pigment particles less than 1um.