Abstract: An object of the present invention is to provide an authenticity indicator that cannot be easily forged, that is clearly distinguishable, and that can be elaborately designed. An authenticity indicator 101 is in the form of a sheet and can be checked for its authenticity by observing the light reflected from it. The authenticity indicator comprises a first reflective layer 12 comprising a reflective area 12a that reflects specified light, and a second reflective layer 15 that reflects specified light. The reflective area of the first reflective layer has a cholesteric liquid crystalline structure. The second reflective layer comprises a volume hologram.

Abstract: A counterfeiting prevention label 1 has a label base 3 including a base sheet 31, and a volume hologram 2 including a volume hologram layer 22 and formed on the base sheet 31. The volume hologram 2 is extended between the upper side 31a and the lower side 31b of the label base 3. The opposite end surfaces of the volume hologram 2 are flush with the end surfaces of the label base 3, respectively. The volume hologram 2 may be placed in a depression 3a formed in the front surface of the label base 3. The volume hologram 2 and the label base 3 are blanked out after transferring the volume hologram 2 from a transfer sheet 10 to the label base 3.

Abstract: The invention provides (1) a volume hologram transfer foil comprising a substrate and protective layer, a volume hologram layer and a heat seal layer stacked on the substrate in this order, wherein a multilayer structure comprising the protective layer, the volume hologram layer and the heat seal layer in this order is releasable from the substrate, and (2) a volume hologram transfer foil wherein the above protective layer is used as a heat seal layer. The heat seal layer comprises a polyester resin having a glass transition temperature of ?10° C. to ?30° C. With the invention, thermo-compression adhesion of the volume hologram layer to any application member, especially a polyester resin card is improved, so that the invention provides a volume hologram transfer foil useful for prevention of illegal copying, and a volume hologram multilayer structure formed using such a transfer foil.

Abstract: A method of producing a volume hologram laminate which can regenerate a hologram image in an arbitrary wavelength by a simple process. The method uses a volume hologram forming substrate which includes: a substrate, a volume hologram layer formed on the substrate and containing a photopolymerizable material, a resin layer, formed on the substrate so as to contact to the volume hologram layer, containing a resin and a polymerizable compound. The producing method includes processes of: a hologram recording process to record a volume hologram to the volume hologram layer, a substance transit process of transiting the polymerizable compound to the volume hologram layer, and an after-treatment process of polymerizing the polymerizable compound.

Abstract: The present invention provides an optical diffusion device, which can exhibit discontinuously different optical properties only in desired regions without creating any difference in grades and/or breaks, facilitate control of the optical diffusion properties, and prevent the occurrence of the stray light, as well as provides a projection screen and a design member, both using the optical diffusion device. An exemplary optical diffusion device according to this invention includes a base, and a cholesteric liquid crystal polymer layer provided on the base and composed of a plurality of diffusion regions arranged on a plane. A diffusion angle of one of the diffusion regions (e.g., first diffusion regions) of the cholesteric liquid crystal polymer layer is different from a diffusion angle of another of the diffusion regions (e.g., second diffusion regions).

Abstract: A major object of the present invention is to provide a volume hologram transfer foil that gives a volume hologram laminate higher in antiforgery function, The present invention achieves the object by providing a volume hologram transfer foil comprising: a substrate, a volume hologram layer carrying a recorded volume hologram that is formed on the substrate, and an image forming layer carrying a formed image and a heat seal layer containing a thermoplastic resin that are formed on the volume hologram layer, and comprising no reflective layer having a function to reflect light.

Abstract: An object of the present invention is to provide an authenticity indicator that cannot be easily forged, that is clearly distinguishable, and that can be elaborately designed. An authenticity indicator 101 is in the form of a sheet and can be checked for its authenticity by observing the light reflected from it. The authenticity indicator comprises a first reflective layer 12 comprising a reflective area 12a that reflects specified light, and a second reflective layer 15 that reflects specified light. The reflective area of the first reflective layer has a cholesteric liquid crystalline structure. The second reflective layer comprises a volume hologram.

Abstract: This invention provides a volume hologram photosensitive composition, which can realize a hologram having an excellent brightness and, at the same time, having excellent heat resistance and mechanical strength, and a photosensitive medium for volume hologram recording using the volume hologram photosensitive composition. The volume hologram photosensitive composition comprises at least a photopolymerizable monomer, a photopolymerization initiator, a sensitizing dye for sensitizing the initiator, and a binder resin. The binder resin comprises a heat curing resin, and optionally a thermoplastic resin, and the thermoplastic resin is contained in an amount of 0 to 25% by weight based on the total solid content of the photosensitive composition.

Abstract: The invention provides (1) a volume hologram transfer foil comprising a substrate and protective layer, a volume hologram layer and a heat seal layer stacked on the substrate in this order, wherein a multilayer structure comprising the protective layer, the volume hologram layer and the heat seal layer in this order is releasable from the substrate, and (2) a volume hologram transfer foil wherein the above protective layer is used as a heat seal layer. The heat seal layer comprises a polyester resin having a glass transition temperature of ?10° C. to ?30° C. With the invention, thermo-compression adhesion of the volume hologram layer to any application member, especially a polyester resin card is improved, so that the invention provides a volume hologram transfer foil useful for prevention of illegal copying, and a volume hologram multilayer structure formed using such a transfer foil.

Abstract: A magnetic card of the invention comprises a card substrate 11 on which a magnetic layer 12, a thin-film layer 13 formed of a metal or a metal compound for concealing the magnetic layer, a printed layer 14 and a volume hologram layer 15 are successively provided, wherein magnetic information is recorded on or read from a volume hologram layer side. The volume hologram layer 15 is composed essentially of a photosensitive material comprising a cationic polymerizable compound, a radical polymerizable compound, a photo-radical polymerization initiator system that is sensitive to light of a specific wavelength to polymerize the radical polymerizable compound, and a photo-cationic polymerization initiator system that is less sensitive to the light of a specific wavelength but sensitive to light of another wavelength to polymerize the cationic polymerizable compound.

Abstract: A counterfeiting prevention label 1 has a label base 3 including a base sheet 31, and a volume hologram 2 including a volume hologram layer 22 and formed on the base sheet 31. The volume hologram 2 is extended between the upper side 31a and the lower side 31b of the label base 3. The opposite end surfaces of the volume hologram 2 are flush with the end surfaces of the label base 3, respectively. The volume hologram 2 may be placed in a depression 3a formed in the front surface of the label base 3. The volume hologram 2 and the label base 3 are blanked out after transferring the volume hologram 2 from a transfer sheet 10 to the label base 3.

Abstract: A magnetic card of the invention comprises a card substrate 11 on which a magnetic layer 12, a thin-film layer 13 formed of a metal or a metal compound for concealing the magnetic layer, a printed layer 14 and a volume hologram layer 15 are successively provided, wherein magnetic information is recorded on or read from a volume hologram layer side. The volume hologram layer 15 is composed essentially of a photosensitive material comprising a cationic polymerizable compound, a radical polymerizable compound, a photo-radical polymerization initiator system that is sensitive to light of a specific wavelength to polymerize the radical polymerizable compound, and a photo-cationic polymerization initiator system that is less sensitive to the light of a specific wavelength but sensitive to light of another wavelength to polymerize the cationic polymerizable compound.