temperature isopropyl alcohol ipa was used to wipe the test substrate prior to activator application to mimic accelerated aging the samples were exposed to uv light for 7 days and gel times were recorded again as described previously the result can be seen below and in table 4 it can be seen that cure times were not adversely affected after uv ageing the remaining composition comprising the following activators are suitable for use in uv blocking pack activator part b 10 2 morpholin 4 ylthio 1 3 benzothiazole santocure mbs 12 2 cyclohexylamino thio benzothiazole santocure cbs 14 n n 4 trimethylaniline dmpt 23 2 tert butylamino thio benzothiazole control gel times were also carried out using a thermocouple approximately 0 6 g of each material was used 0 6 g of material was dispensed through a static mixer into a test tube 12 u00d7 75 mm pyrex and a thermocouple then inserted into the test tube temperature increase from insertion of the thermocouple over time is recorded the samples were tested before and after uv exposure for 7 days the results can be seen in fig2 to 17 good correlation was obtained between the gel times observed with hand mixing and those recorded using a thermocouple approximately 15 seconds must be allowed between weighing the samples and recording the response for the instrument set up it can be.