The raw materials of black masterbatch masterbatch mainly include: carrier, dispersant, colorant, filler, and additives. The carriers of masterbatch are mainly general plastics (5 categories such as PE, PP, PVC, PS, ABS) and engineering plastics (PA, PC, POM, PPO, PET, PBT, PPS, PEK, PKKT, PES, PSF, PAR, etc.), which are less toxic or non-toxic;
Dispersants mainly include: polyethylene wax, polypropylene wax, modified polyethylene wax, paraffin, etc., with less toxicity or non-toxicity; The fillers mainly include: calcium carbonate, kaolin, talc, mica powder, wollastonite, barium sulfate, etc., which may be mixed with a small amount of toxic heavy metals; Additives mainly include: antioxidants, light stabilizers, coupling agents and nucleating agents, etc., with low toxicity. Therefore, the toxic substances in masterbatches mainly come from colorants.
Inorganic pigments mainly include: chromate (chromium yellow, strontium yellow, zinc yellow, etc.), oxide (iron red, titanium dioxide, chromium oxide, etc.), sulfide (cadmium red, chrome yellow, etc.), silicate (ultramarine, etc.), ferricyanide (Hualan, etc.), metal pigments (copper powder, aluminum powder, etc.), natural pigments (clay, laterite, etc.), other pigments (cobalt blue, etc.).
Most inorganic pigments are insoluble in oil and water and have a certain particle size, so they are non-toxic. Only those inorganic pigments that contain heavy metal salts such as lead and chromium have harmful intermediates. Lead chromium pigments are mainly inorganic pigments composed of lead chromate, lead molybdate or lead co-precipitated compounds insoluble in water, and the color ranges from yellow to red.
The black master manufacturer has found that the inorganic pigments currently used, only the acid-soluble lead and acid-soluble chromium in Danhuang, zinc chromate and lead white account for a higher proportion of the total lead and chromium content, which is toxic; For other inorganic pigments, they are basically insoluble in oil or water, and most of the particle sizes of these pigments are greater than 10 um, rather than 0.5~5 um, so the toxicity is very low.
Organic pigments mainly include: phthalocyanine, reducing dyes, condensed azo macromolecules, azo series, quinacridone, lakes, chelates, isoindolinones, acid dyes and salt-based dyes.
In general, organic pigments are not soluble, and as a result, most organic pigments are less toxic. On the other hand, because pigments are insoluble in water and insoluble in some common solvents, the harm caused by organic pigments is mainly caused by processors and manufacturers. The toxicity in organic pigments mainly comes from some intermediates, such as nitro compounds, water-soluble amines, etc., which cause heterosexual hemoglobin to be generated in the body, resulting in blood poisoning.
Although organic pigments are not very toxic to living organisms, some impurities will inevitably be substituted into the production of pigments, and these impurities have a certain toxicity. For example, trace amounts of aromatic amines: national regulations strictly stipulate that in food packaging materials, the aromatic amines contained in pigments cannot be higher than 500×0.000001. traces of heavy metals; Polychlorinated biphenyls (PCBs): Due to their wide distribution and persistent toxicity, they are severely restricted in the United States and the European Union.
In addition to paying attention to these impurities in the production process, black master manufacturers also need to choose appropriate additives, because some additives will trigger the toxicity of organic pigments and increase the toxicity of organic pigments.