A proprietary term used for a type of single sheet color proof used to check the registration of the colors, the existence of any egregious blemishes or other undesirable marks, and to confirm size and position of page elements. The Cromalin process utilizes several sheets—commonly four, one for each process color—of clear photosensitive plastic. Each sheet is exposed to one of the color separation negatives, and, when treated with process colors, dots will adhere to the surface of the plastic in the image areas. The four exposed sheets of plastic—each containing a different process color—are aligned with each other in proper register and laminated together.
'Cromalin is a trademark of du Pont.