This is a very sensitive and difficult process which creates lot of rejection if necessary precautions are not taken in the process. At this stage, biscuitware is first selected without any blemishes for Under Glaze Decoration. In some factories they do Under Glaze Decoration even on the dried clayware directly. The following are few of the decoration techniques:
1.Stamping with, for example, the Murray Curvex Machine
2.Banding and Lining
3.Spraying by hand or by machine
4.Under glaze Lithography
5.Printing
6.Silk Screen Printing
Stamping is a very useful method and with Murray Curvex Machine the productivity can be increased to maximum level. The Murray Curvex machine prints by an off-set process using a gelatine pad . In some machines, rubber stamps are used.
Banding and Lining can be done by hand or by machine and so can spraying. There are spraying machines available which allow bands to be sprayed with sharp outlines. The plate is held in a vacuum chuck and spun in a vertical plane, while it is sprayed with a spray gun. Hollowware also can be sprayed by this machine.
… to be contd
