Minimal blistering time

Step 1. May be to examine the scorch time of the compound for seasonal or special cause trends. In rubber molding, we are trying to flow the material and vulcanize the material in one process. The onset of vulcanization, scorch, may be providing some of the viscosity and pressime increases we need in the product cavity to eliminate blisters and minimize flash. We may need to establish a range of acceptable scorch rates and adjust the accelerator level in the formula to keep the scorch rate in the good molding window. This adjustment may need to be a one-time affair, or it may need to be seasonal as shown in Figure 16C.12. 

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