A latent image receiving sheet comprises a substrate bearing microcapsules having walls of a nonmeltable polymer which is a thermosetting aminoplast resin. The walls of the microcapsules have an elongation less than 1%, and the image receiving sheet and microcapsules are resistant to heat. Surprisingly, the latent image receiving sheet capsules nonetheless rupture upon application to the record material of a point source energy input or pulse comprising a ΔT of at least 115°C per one millisecond. The latent image receiving sheet may be an ink transfer sheet or print plate, a gravure sheet, a cryptic message receiving sheet or an imageable sheet.