鱼明胶介质中AgBr/I纳米粒子的生长与感光性能

本文以鱼明胶为分散介质,采用双注法制备AgBr/I纳米粒子乳剂,控制银盐与卤溶液的注入速率(R),以TEM观测了粒子的生长,据此探讨了该乳剂中AgBr/I纳米粒子平均粒径(d)及分布(±σ)与反应条件的关系.发现在R为1.3 mmol/min^-8 mmol/min范围内,随R增大,d减小,R-d间呈良好的线性关系.除个别外,±σ值变化不明显.对于该纳米粒子乳剂采用二氧化硫脲进行化学敏化,结果表明:适当增加二氧化硫脲的加入量和延长敏化时间,均可有效提高乳剂的感光度,并有助于改善其低照度互易律失效,此外还揭示了曝光光源色温对该乳剂感光性能的影响.

THE GROWTH AND SENSITIVITY OF NANO-SIZED SILVER IODOBROMIDE PARTICLES IN FISH GELATIN AS DISPERSED MEDIUM

By means of varying addition rate of the reactants in a double jet precipitation,the growth of nano sized silver iodobromide particles in an aqueous fish gelatin solution was observed by TEM.The relationship of the average size ( ) and size distribution (± σ ) of the silver iodobromide nanoparticles with the addition rate ( R ) of the reactants was discovered.Increasing R values, values decreases linearly in a region of R values from 1.3 to 8.0 mmol/min,but no significant change of σ values was observed except for one or two data.Thiourea dioxide was used as chemical sensitizer to improve the photographic properties of the nanoparticles silver iodobromide emulsion.The results showed that photographic sensitivity increased by increasing the amount of thiourea dioxide or prolonging the sensitizing time.Improvement in low intensity reciprocity law failure due to thiourea dioxide sensitization was also found.Besides,photosensitive response of thiourea dioxide sensitized emulsion to color temperature of light source at exposure was indicated.