Patent ID: 7102802

Claim:
A method for storing holographic data, said method comprising: step (A) providing an optically transparent substrate comprising a photochemically active dye having structure (I) wherein R 1 and R 3 are independently a C 1 –C 30 aliphatic radical, a C 3 –C 30 cycloaliphatic radical, or a C 2 –C 30 aromatic radical; R 2 is hydrogen, a C 1 –C 30 aliphatic radical, a C 3 –C 30 cycloaliphatic radical, or a C 2 –C 30 aromatic radical; and at least one of the groups R 1 and R 3 comprises in proximity to the nitrone oxygen, a group —X—(P 1 ) a wherein X is independently at each occurrence an oxygen atom, a nitrogen atom, a sulfur atom, or a selenium atom; P 1 is an organic protecting group, and “a” is 1 or 2; step (B) irradiating the optically transparent substrate with a holographic interference pattern, wherein the pattern has a first wavelength and an intensity both sufficient to convert, within a volume element of the substrate, at least some of the photochemically active dye into a photo-product, and producing within the irradiated volume element concentration variations of the photo-product corresponding to the holographic interference pattern, thereby producing an optically readable datum corresponding to the volume element; and step (C) activating the optically transparent substrate to form an intramolecular hydrogen bond to a nitrone oxygen in residual photochemically active nitrone dye, to stabilize the optically readable datum.