A photomechanically produced plate for pictures or type made by exposing a gelatin film under a negative,hardening it with chrome alum,and printing directly from it.

• 珂罗版印刷法，一种通过照相制版工艺制造出来的用于印刷图片或文字的图版，将一层胶制剂薄片置于底片之下，用硫酸铬钾使之坚硬，然后便可直接印刷。