Although the foregoing remarks refer mainly to lithographic colour printing generally, they may with equal effect be applied to many of its more specific branches.
Colour printing for tin-plate decoration will be fully discussed in a subsequent chapter.
Transfer printing for ceramic decoration presents many features in common with transfer printing for metal decoration. Printing colour transparencies is a commercial phase of colour work which is productive of many curious and attractive effects. Unlike the ordinary colour prints, the transparency is intended for exhibition both by reflected and transmitted light. The paper is of a thin, tough quality, and the first printing is usually a white of good covering power and exceptional opacity. It is not necessary to print a solid white groundwork for the coloured design. If an intense brilliant colour is required by transmitted light the omission of part of the white printing will add considerably to the effective character of the design. A brilliancy secured in such a manner may be still further intensified by printing the colour or colours in register on both sides of the paper. This can be easily accomplished by first allowing the cylinder covering to take an impression from the stone, and then, with the sheet laid in the gripper, make a second impression in the usual way immediately after.
The first print, which might be termed the transfer, will then be made in accurate register on the back of the sheet.
Semi-transparent, or even transparent, effects can be obtained with any of the colours by an omission of the white printing from the parts affected. Complete opacity may be secured by its introduction.
This print is afterwards rendered more or less transparent by coating it with a suitable varnish.