Process control for highlight color with developer switching

Abstract

Highlight color imaging apparatus and method for creating highlight color images that allows the inter-image areas to be used for developability or other control functions notwithstanding the necessity of developer switching. The black and highlight color images are separately formed and the order of image formation is one where the black image (B1) for the first copy is formed, followed by the highlight color image (C1) for the first copy; then the highlight color image (C2) for the second copy; then the black image (B2) for the second copy; then the black image (B3) for the third copy and finally the highlight color image (C3) for the third copy. With the foregoing order of image creation, developer switching is not required when two adjacent images are the same color. When developer switching is not required the inter-image area can be used for process control such as developability to form a test pattern thereat. Thus, in the example above, the area between the two adjacent color images (C1, C2) is available for forming a color test patch. Likewise, the area between the two black images (B2, B3), is available for forming a black test patch.