图书资料、文物档案部门,利用黑白照相材料记录绝版书刊、文物档案;公安部门则用以记录刑事罪证、以及印制国民身份证照片等。这些黑白照相材料都做为重要档案长期保存,要求三十年内不变黄,不褪色。但影响黑白照相材料保存性的因素很多,诸如空气中的污染性气体、存放照相材料的条件、胶片或相纸接触含有害物质的纸张或塑料等等。这些方面需针对具体情况研究解 The books and information and cultural relics archives departments use black and white photographic materials to record out-of-date books and periodicals and cultural relics files; the public security departments record criminal convictions and print national ID cards and the like. These black and white photographic materials are long-term preservation as an important file, requiring thirty years, the same yellow, do not fade. However, there are many factors that affect the preservability of black and white photographic materials, such as polluted air, the conditions under which photographic materials are stored, the exposure of film or photographic paper to paper or plastic containing harmful substances, and the like. These aspects need to be solved on a case-by-case basis