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Is tinting strength the same as color strength?


Tinting strength correlates with color strength for carbon blacks in the Regular Color and Utility grades (primary particle sizes above 20 nanometers). However, this is not the case for finer carbon black grades (such as Medium Color and High Color grades) because very fine carbon black grades do not completely disperse when measuring tinting strength. The result is that a false shade is achieved (too light) that does not correlate to color strength.
Masstone: what is this?


Masstone is a measure of the blackness of a particular grade of carbon black.
Melt Temperature: Is melt temperature affected by the amount of carbon black in a formulation?


Increasing the amount of carbon black in a formulation generally increases process melt temperature under consistent conditions. Higher melt temperature results from the higher shear that is generated with increased carbon black loading.
Morphology: how does carbon black morphology influence masterbatch viscosity?


The two main carbon black factors that need to be considered in predicting the viscosity of a masterbatch are carbon black surface area and carbon black structure. Increasing the surface area and structure of a carbon black typically will increase the viscosity of a masterbatch at a given loading. Surface area and structure need to be considered together. For example, a high surface area, low structure carbon black could give a similar viscosity as a low surface area, high structure carbon black at equal loading.
Particle size: how does carbon black particle size relate to carbon black surface area?


Carbon black particle size is inversely proportional to carbon black surface area.
Primary particle: what is a carbon black primary particle?


During the manufacturing process, the first particulates to form are called primary particles. At formation, these particles are semi-solid. As these particles move through the reactor, they collide and fuse together to form clusters called aggregates.
Screen 100#: what does Screen 100# mean? I find this figure on the QAC of the material I buy. Which is the size of particles retained on a 100# screen?


The size of particles retained on a 100# screen depends on the screen itself. That is, the number of meshes (#) indicates the number of threads per inch. The "opening" of the screen depends not only on the number of meshes, but also on the diameter of the single thread.<BR>As a reference value, we can say that a 100# screen will retain particles with dimensions of 140 to 180 microns. A 200# screen will retain particles of 70 to 90 microns, for example.
Under what environment does carbon black decompose?


Typically, carbon black begins to decompose between 450 degrees C to 500 degrees C, under air or oxygen. Carbon black does not decompose at these temperatures under a nitrogen atmosphere. Ash testing of carbon black is typically done at 550 degrees C.
UV Protection: How is UV Protection linked to the use of different types of carbon black?


The amount of protection against UV light is linked to the microscopic structure of carbon black in the final product. In fact, carbon black is made of very fine prime particles that are fused into clusters, known as primary aggregates. To a large degree, the average prime particle size determines the amount of optically available surface area presented by the primary aggregate. In other words, the finer the prime particle, the more surface area remaining exposed in the aggregate.<BR><BR>Since carbon black absorbs UV radiations, they are prevented from degrading the polymer chains (therefore preventing degradation of the final product). The higher the surface area, the higher the light absorption efficiency.<BR><BR>This means that a carbon black with finer particle (say, <25nm) shows a better efficiency in UV protection of the final compound.</p><BR><BR>Note: it should also be noted that a good DISPERSION of carbon black in the polymer matrix is essential to reach good UV protection. If a small particle size carbon black is not well dispersed in the polymer matrix, the UV protection cannot be good at all.
UV protection: which carbon black factors affect the UV protection of a plastic compound?


The four main factors that influence the UV protection of a plastic compound are: carbon black particle size, carbon black structure, carbon black dispersion quality in the plastic matrix, and carbon black loading in the plastic formulation. Please reference Cabot Corporation’s Technical Report S-115 for additional details regarding UV protection of polymers.