A UV-curable composition, comprising: (meth)acrylic polymer and/or ethylene-vinyl acetate copolymer; the glass transition temperature Tg for said (meth)acrylic polymer and/ or ethylene-vinyl acetate copolymer being -50 to 47°C; curable components, comprising polyfunctional mercaptan and polyfunctional epoxy resin, wherein (a) said polyfunctional mercaptan is a mercaptan compound having 2 or more sulfhydryl groups, wherein the UV-curable composition contains 0.01 to 1.1 moles of sulfhydryl groups per 100 grams of said (meth)acrylic polymer and/or ethylene-vinyl acetate copolymer; and (b) said polyfunctional epoxy resin is an epoxy resin having 2 or more epoxy groups, wherein the UV-curable composition contains 0.005 to 1.05 moles of epoxy groups per 100 grams of said (meth)acrylic polymer and/or ethylene-vinyl acetate copolymer and wherein the molar ratio for the amount of sulfhydryl groups in said polyfunctional mercaptan to the epoxy groups in said polyfunctional epoxy resin is 1.2:1 to 1:1.2; and photobase generator, wherein the UV-curable composition contains 0.5 to 20 grams of the photobase generator per 100 grams of said (meth)acrylic polymer and/or ethylene-vinyl acetate copolymer wherein the T g values are calculated as disclosed in the appended description.. (meth)acrylic polymer and/or ethylene-vinyl acetate copolymer; the glass transition temperature Tg for said (meth)acrylic polymer and/ or ethylene-vinyl acetate copolymer being -50 to 47°C; curable components, comprising polyfunctional mercaptan and polyfunctional epoxy resin, wherein (a) said polyfunctional mercaptan is a mercaptan compound having 2 or more sulfhydryl groups, wherein the UV-curable composition contains 0.01 to 1.1 moles of sulfhydryl groups per 100 grams of said (meth)acrylic polymer and/or ethylene-vinyl acetate copolymer; and (b) said polyfunctional epoxy resin is an epoxy resin having 2 or more epoxy groups, wherein the UV-curable composition contains 0.005 to 1.05 moles of epoxy groups per 100 grams of said (meth)acrylic polymer and/or ethylene-vinyl acetate copolymer and wherein the molar ratio for the amount of sulfhydryl groups in said polyfunctional mercaptan to the epoxy groups in said polyfunctional epoxy resin is 1.2:1 to 1:1.2; and (a) said polyfunctional mercaptan is a mercaptan compound having 2 or more sulfhydryl groups, wherein the UV-curable composition contains 0.01 to 1.1 moles of sulfhydryl groups per 100 grams of said (meth)acrylic polymer and/or ethylene-vinyl acetate copolymer; and (b) said polyfunctional epoxy resin is an epoxy resin having 2 or more epoxy groups, wherein the UV-curable composition contains 0.005 to 1.05 moles of epoxy groups per 100 grams of said (meth)acrylic polymer and/or ethylene-vinyl acetate copolymer and wherein the molar ratio for the amount of sulfhydryl groups in said polyfunctional mercaptan to the epoxy groups in said polyfunctional epoxy resin is 1.2:1 to 1:1.2; and photobase generator, wherein the UV-curable composition contains 0.5 to 20 grams of the photobase generator per 100 grams of said (meth)acrylic polymer and/or ethylene-vinyl acetate copolymer wherein the T g values are calculated as disclosed in the appended description..