The document discusses various techniques for printing designs and patterns onto fabric, including flat-bed screen printing, rotary screen printing, engraved roller printing, and heat transfer printing. Flat-bed screen printing is a manual process that allows for multiple strokes but is slow with design limitations. Rotary screen printing is faster and allows for continuous patterns but has smaller repeats. Engraved roller printing provides high design capability but is expensive for short runs. Heat transfer printing provides high quality prints with fewer defects and is economical for short runs. The preparation of printing pastes and steps in the printing process are also outlined.
3. Textile Printing
The application of color to a fabric in a design or pattern
(localized dyeing)
Modern printing generally incorporates one of the following techniques:
Flat-bed screen printing
Rotary screen printing
Engraved roller printing
- Heat transfer printing
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4. I
Types Of Printing Processes
Automatic Flat Screen Printing
A Approximately 17%of printed goods
B. Advantages
1. Largerepeats
2. Multiple strokes for pile fabrics
C. Disadvantages
1. Slow
2. No continuous patterns
Rotarv Screen Printing
k Approximately 50% of printed goods
B. Advantages
1. Fast
2. Quick changeover of patterns
3. Continuous patterns
C. Disadvantages
1. Design limitations
2. Small repeats
& Engraved Roller Printing
I
A Approximately 26%of printed goods
B. Advantages
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1. High design capability
a. Finedetail
b. Multiple tones
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5. C. Disadvantages
1. Copper cylinders very expensive
2. Not economical for short runs
3. Requires highly skilled workers
Heat TransferPrinting
k Approximately 7% of printed goods
B. Advantages
1. High quality prints
2. Fewer seconds
3. Economical for short runs
4. Practically pollution free
C. Disadvantages
1. Slow
2. Primarily only for polyester
6. Steps In Printing Process
1. Preparation of print paste
2. Printing of fabric
3. Drying
4. Fixation of dyestuff
5. Washing - off
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7. I
Preparation Of Printing Pastes
Type of specific formulation used depends on the fiber, the colorant
system used and, to some extent, the type of printing machine.
TvDicaZ Inmedients Used Include:
Dyes or pigments
Thickeners
Binders, cross-linking agents
. Sequestrants
Dispersing agents - surfactants
Water-retaining agents (humectants)
Adhesion promoters
Defoamers
Catalysts
Hand modifiers
8. Flat-Bed Screen Printing
Mechanization of hand screen process
Fabric glued to blanket
Screens rise and fall
Printing done while screen i down position
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Rod or blade squeegee system
Up to four strokes possible
Slow process
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11. Rotary Screen Printing
Continuous screen printing process
Fabric glued to blanket
Fabric moves under rotating screens
Rod or blade squeegee system
Fine adjustments easily made
Speeds up to 100 yd/min
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13. 1
Figure 17-3 Diagrammatic View Of A
Roller-Printing System
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14. Heat Transfer Printing
Advantages
- Easier handling of units
- Easier training of operators
-Better registration and clarity
- Fewer seconds
- Inventory i paper
n
-Pollution - free
Disadvantages
a -Slow
- Limited to synthetic fibers, mainly polyester
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