Abstract: A gamma radiation dosimeter comprises a polyester film substrate, of which a central circular region is coated with a gamma-radiation sensitive layer which is covered by an overlayer. The radiation-sensitive layer is formed from styrene-acrylonitrile copolymer and contains 1-bromoadamantane and a leuco dye. The overlayer is formed from an acrylic resin binder containing a UV-absorber. The central region is surround by an annular region which is divided into six equally-sized sections, each of which is printed in a color which corresponds to the color developed in the central region when it has been exposed to successive increasing amounts of gamma radiation. After exposure of the device, the amount of radiation to which the device has been exposed can be determined by comparing the color generated in the region with the colors of the six sections.

Abstract: A device for monitoring UV radiation received by the skin comprises a housing. Adhesive on a face of the housing secures the device to the skin. A patch of irreversible UV sensitive material which changes color on being subjected to UV radiation is applied to an inner surface of the housing and receives UV radiation reflected from the skin. The color of the UV sensitive patch is compared with reference colors on the housing for determining the quantity of UV radiation to which the skin has been subjected.

Abstract: Photopolymers which are derivatives of polyvinyl alcohol and are useful as resists, stencils and relief images are made by reacting a compound having one or two formyl or acetal groups, such as terephthaldehyde, a naphthalene dialdehyde or the reaction product of an acetal and hydroxy-benzaldehyde, with an aromatic or heterocyclic compound carrying an acetyl group, so as to produce an intermediate of the formula: ##STR1## and reacting this with a polyvinyl alcohol to yield a photosensitive product of the formula: ##STR2## wherein m is 0 or 1, n is an integer from 1 to 6, X is an aromatic or heterocyclic group carrying at least one polar group and Z is an aromatic group of the formula: ##STR3## wherein R' and R", when both are present, are the same or different and each represents a hydrogen or a halogen atom or an alkyl, alkoxy, hydroxyalkyl, hydroxy, nitro or cyano group.