Rotary and roller printing are two methods of textile printing. Roller printing involves engraving designs onto copper rollers and printing one color at a time onto fabric using pressure. Rotary printing uses perforated cylinders or screens to print designs continuously onto fabric using paste that passes through the perforations. Rotary printing allows for larger designs, more colors, and fresher designs compared to roller printing. Both methods have advantages like production levels but rotary printing provides higher quality and larger scale printing capabilities.
3. ROLLER PRINTING
• The printing of textiles from engraved copperplates was first practiced by Bell in 1770.
• Each color of the design requires a separate cylinder. Sometimes referred to as cylinder or
machine printing.
• Engraved roller printing is a modern continuous printing technique developed in the late 19th
and early 20th century.
• Until the development of rotary screen printing, it was the only continuous technique.
• In this method, a heavy copper cylinder (roller) is engraved with the print design by carving the
design into the copper.
• It was entirely obsolete.
4. ROTARY PRINTING
• Rotary screen printing is a continuous printing
process. A perforated cylinder or spherical
screen are used which are automatically fed with
paste from inside by pump and paste pass
through perforation.
• The screen is produced by photochemical
means, in that a photopolymer coating is
applied to the surface of the screen.
• A typical rotary screen print machine would
have an in-line configuration with upwards of
seven or eight print stations available, each
printing one color.
• The cylindrical printing screen itself is a very
fine ‘honey combed’ type mesh.
5. COMPARISON OF ENGRAVING
DEPARTMENT
Roller Printing
In which we Engrave by mechanical and chemical
then coat with chrome for Durability of screen
and copper is soft.
In which we use different type of chemical for
etching and mechanical process also available.
Laser engraving also use.
If we Engraved the roller for one design, then it
can’t be use for other design.
In which engraved Portion give the design.
Engraving of roller is expensive.
In which there no mesh problem for printing.
It engrave give less fine design.
Rotary Printing
In which we engraved by laser, Manually, Ink jet
and wax and no requirement of coat because
nickel is durable and prover cad system.
In which there is chemical etching method used
for engraving.
In this case screen is reusable for other design
because photoelement easily washable.
In which engraved portion give design by
pressure of paste through perforation.
Engraving of roller in inexpensive.
In which mesh have very important for design
(toner, fine).
In which we obtained more fine design.
6. COMPARISON OF ENGRAVING
DEPARTMENT
Roller Printing
In which there is no effect in coating on design
because design is engraved portion.
For photoengraving we must make positive and
negative image for etching on roller for required
design and separation of color.
In which in case of photoengraving we use same
process as such rotary screen but after exposing
of masked screen to light then we dip the copper
in acid and un-exposed area remove the
chemical and etch copper because copper is
sensitive for copper.
The depth of scales depend upon time duration
in acid of screen.
After that we remove the photochemical by
mineral and then coated.
Rotary Printing
The quality and thickness of the coating on
screen are determined by the down-ward
movement of the squeegee speed, viscosity of
the lacquer, squeegee diameter, rubber hardness
and rubber thickness
In rotary this process is also same and
separation of color.
In this case we washed the un-exposed area with
help of hot water we don’t need acid.
The depth depends upon the layer of
photochemical.
In we don’t remove the chemical from every part
of screen on masked area and then cured.
7. COMPARISON OF PRINTING
PROCESS
Roller Printing
In which we set the screen according
to color depth for printing because of
color contamination.
In which paste is taken from color box
evenly spread on roller for printing.
In which color doctor evenly spread
the color and lint doctor remove the
contamination.
Design is print on fabric from
engraved portion by pressure.
It can print woven and tricot fabric.
Rotary Printing
In which there is no setting of color
according to depth but in certain
designs, particularly those containing
tonal areas, it is advisable to print one
color on top of another.
In which past is evenly spread inside
the roller and squeegee system work.
In this case there is no lint doctor and
color doctor use for pressure the paste
through perforation.
In which design is print from
perforation.
It can print woven and knitted fabric.
8. COMPARISON OF PRINTING
PROCESS
Roller Printing
In which large design can not be print
wide 1.8m.
In which maximum 15 color can be
print and lack of freshness of design.
In this case (?)
In which temperature of dryer is
maintained because This is particularly
critical for designs in which a high
proportion of the total area is printed
(high percentage cover).
Rotary printing
In which there is no problem of large
design and large repeat can also be
print by Zimmer.
In which 16-32 color can be print and
there is no problem of freshness of
design.
Sometimes more than one pass is
required to achieve uniformity and
adequate penetration of paste for
irregular and thick fabric. In some
machines the squeegees this fills the
mesh in the printing areas of the
screen with paste before the screen
touches the fabric.
In this temperature of dryer also have
same importance
9. SQUEEZING MECHANISM
Roller Printing
In which there is no squeegee system for printing
just press the roller on fabric.
Pressure of roller is very crucial for same color of
print in it.
In which there is problem of impression of design
because to the mandrel ends inevitably produces
some bending and the fabric edges tend to be
printed more heavily than the middle.
In which above problem solve making more lapping
in center for continuous impression.
In which problem of changing the roller time which
50% of working time of production of printed fabric.
In which contact time and pressure of roller with
fabric show the paste flowing.
Pressure of roller is high.
Rotary Printing
In which there are many squeegee system like
conventional, air and magnetic squeegee.
Pressure of roller is not crucial for printing same
depth impression.
In which If the squeegee pressure is uneven, the
volume of print paste applied across the width will
vary, resulting in an unlevel appearance in the final
print.
The Zimmer brothers used the magnetic-rod
squeegee system in their rotary machines which
solve the problem.
In which there is no such problem.
In which pressure, pore size of screen, kinetic
motion of paste has direct effect on the quantity of
paste flowing through a screen and fabric type.
Pressure of roller is not high
10. COMPARISON OF MACHINE
Roller Printing
In which we use roller for printing.
In which color is taken from furnishing roller.
In which pressure bowl play important role in
printing and roller print around it.
In which fabric move with help of roller drive and
pressure bowl.
In which continuous use of blanket must replace.
Skill of operator is good.
In which lapping is required for even printing.
In which no adhesive material used to make contact
the fabric with bowl.
In which there is less penetration of past because
forcing the paste by pressure.
Rotary printing
In which we also use roller, but perforation is used
for printing.
In which color is take with help of suction pipe from
tank of color.
In which we use belt for printing and roller print on
it.
In which fabric move with the help of belt.
In which blanket is continuously washed under the
conveyer belt.
Skill of operator is not good.
In which there is no use of lapping.
In which adhesive material is used for making fabric
contact with blanket.
In which there is no such problem.
11. ROLLER PRINTING
Advantages
High production
Upton 16 colors can be used
Complex designs are possible
Fine vertical lines can be produced
Can be used for printing any style
Sharp lines can be produced
Floral designs can be produced
Disadvantages
Lack of freshness of the design
Large design (wider width not more than 1.8 m) is
not possible
Horizontal lines and large blotches are difficult to
produce
If back grey is used, then stitch impression
Sequence of colors printed (light colors earlier than
darker)
Higher coloring effect not possible
Design change time is high
Lower production in case of more colors
Engraving of rollers is expensive
Not suitable for short runs
12. ROTARY PRINTING
Advantages
It needs relatively cheap equipment.
It has very few preliminaries.
This type of printing permits printing on almost
any surface.
Areas of far greater size can be stenciled. Frames
1.27m X 1.52m (50” X 60”) are frequently used
for textile printing.
Surface to be printed need not be flat.
It give high production than roller.
Can be used for printing any style
Sharp lines can be produced
Floral designs can be produced
Disadvantages
Not suitable for small scale
Not environmentally friendly because this
method used lot water and drain of chemical.
This arises from inaccurate screen placement or
fabric movement, from the fabric slipping on the
blanket because of poor adhesion, or from
distortion of the screen mesh by the drag of the
squeegee.
Off-contact printing cause the splashing of
color.
When printing consecutive screen repeats, the
screen frame inevitably falls on part of the area
most recently printed and may leave an
impression.