Hologram recording material - by coating a rigid or flexible support with gelatin, and sensitising with aq. ammonium di:chromate soln.

摘要

Process for prodn. of a hologram recording material with a flexible or rigid support, consists of preparing a 12-18% suspension of pure gelatin in water and mixing to cause complete dissoln. at 20 deg.C, followed by mixing for 5-10 mins. at 70 deg.C; filtering the soln. using a filter maintained at 50 deg.C; cooling to 40 deg.C and maintaining the temp. at this; adding 0.5 wt.% ammonium dichromate w.r.t. gelatin and mixing to achieve complete dissoln. The bath is then maintained at 40 deg.C and the support is immersed in the bath for ca. 1 min. and withdrawn at 1-5 cm/min. The coated support is dried in air in the vertical position for 1 hr., then the material is hardened in an oven for 2 hrs. at 150 deg.C. The material is then sensitised by immersion for 5 mins. in a 4-10% aq. ammonium dichromate soln. and stored in darkness at 20-30 deg.C for a max. of 48 hrs. in air at 30-40% humidity. Prods. have improved efficiency of diffraction and signal/noise ratio than previous materials based, e.g. on silver halide materials and give holograms with high resolution.