Radiation dosimeter and method for measuring radiation dosage

A process for detecting and/or measuring gamma or electron beam radiation which comprises:

• exposing a dosimeter including a support having a layer of microcapsules on the surface thereof to gamma or electron beam radiation, said microcapsules containing and image-forming agent and a radiation curable composition, said composition being essentially insensitive to visible light and ultraviolet radiation and being sensitive to gamma or electron beam radiation such that, upon exposure to gamma or electron beam radiation, said composition polymerizes and composition polymerizes and hardens said microcapsules;
• subjecting said layer of microcapsules to a uniform rupturing force such that said image-forming agent is released from said microcapsules to form and image, the color, shade or density of said image corresponding to the amount of radiation to which said dosimeter is exposed;
• and
• comparing the color, shade or density of said image with a reference image to determine the amount of exposure.