Rotary Screen Printing:
A printing machine that utilizes seamless cylindrical screens made of metal foil was originally developed in Holland. This process is called rotary screen printing. The machine employs a rotary screen for each color, as in flat screen printing and the design for each rotary screen is made in a manner similar to automatic flat screen printing. Working Flowchart of Rotary Screen Printing are as follows:
Process Flowchart for Rotary Screen Printing
Fabric is fed into the printer section
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The fabric passes under the rotating screens
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Pumping of printing paste
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Squeezing of print paste
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The fabric passes into drying woven
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Curing and Washing
Now I’ll describe the steps in brief as follows –
Steps | Description |
Fabric is fed into the printer section | The fabric to be printed is fed under uniform tension into the printer section of the machine. Its back is usually coated with an adhesive, which causes it to adhere to a conveyor printing blanket. |
The fabric passes under the rotating screens | The fabric is then passed under the rotating screens through which the printing paste is pumped. |
Pumping of printing paste | Printing paste is automatically pumped from the pressure tank. |
Squeezing of print paste | A squeeze in each rotary screen forces the paste through the screen onto the fabric as it moves along at rates of up to 100 yards per minute. |
The fabric passes into drying woven | The fabric is passed into the drying oven for drying. |
Curing and Washing | Curing and Washing are done as a part of finishing. |
This printing method combines the advantages of roller and flat-screen printing techniques. Rotary metal screens are lightweight in contrast to the heavy copper rolls, and they cost less. They give a color depth that is similar to or as good as that of flat screens. Prints of various types and intricate designs with shades of up to twenty colors can be obtained with a high degree of accuracy and sharpness. Rotaries operate continuously rather than starting and stopping as the flats do. Production output is considerably higher than it is on flat screen machines.
Author of this Article: Md. Abu Sayed Founder of Textile Apex Pabna Textile engineering college, Pabna, Bangladesh Email: sayed1952@facebook.com Cell : +8801745214773