Overprinted objects are printed on the objects below them. Therefore, when designing white objects, be sure to never have an overprint, otherwise the white object will not be visible on the print. Solid black objects (100% black) are always automatically overprinted during prepress. To achieve no overprinting on 100% black object, it must be set to 1C/1M/1Y/100K.
Regular 100% black ink will not actually remain completely black, but rather will look dark gray on large surfaces. To achieve a stronger black tone in offset printing, rich black must be used, such as 40C/30M/0Y/100K.
In the case of glue binding, the thickness of the back of the publication depends on the number of pages and the thickness of the paper used. Be sure to ask us how thick your spine should be.