Printing Techniques

Presented by:

S.Rajesh KumarPSG TECH

E-mail: srk3rajesh@gmail.com

PRINTING

The printing is described as localized dyeing, dyes or pigment are applied locally or

discontinuously to produce the various designs.

Printing is the production of all active designs with well defined boundaries made by the

artistic arrangement of a motif is one or more colors. Printing is a process for reproducing

text and image, typically with ink on paper using a printing press.

Screen printing is a printing technique that uses a woven mesh to support an ink-blocking

stencil. The attached stencil forms open areas of mesh that transfer ink as a sharp-edged

image onto a substrate.

Screen printing is also a stencil method of print making in which a design is imposed on a

screen of silk or other fine mesh, with blank areas coated with an impermeable substance,

and ink is forced through the mesh onto the printing surface. It is also known as silk

screening or serigraphy.

Direct Printing:

In direct printing a design is etched into a copper roller. A dye that has been

thickened into a paste with starch, gelatin, or synthetic polymers is applied to the etched

area while the un-etched surface is kept clean.

The color design is transferred to the cloth under pressure. Direct printing may

also involve forcing the paste onto the fabric through a screen, a technique similar to

stencil printing except that the screen controls how much paste is applied to the cloth.

DIFFERENT STYLES OF PRINTING

Direct Printing

Resist Printing:

In resist printing a reverse-printing method, a dye repelling

substance is selectively applied to the cloth, which is then placed in a

dye bath. This method is used for example, to produce white polka dots

on a color background.

Discharge Printing:

In discharge printing, the whole fabric is dyed. A pattern is then

printed on the fabric with a chemical that oxidizes or reduces the dye,

creating a white pattern on a colored background.

Discharge Printing

Discharge Printing

Roller Printing

Flat (Silk) Screen Printing

Rotary Screen Printing

Block Printing

Heat Transfer Printing

Dye Sublimation Printing

Resist Printing

Automatic Print Hand Print

1. Accuracy 1. No Accuracy

2. Limited Production 2. No Limited Production

3. Production is high 3. Production is Low

4. Depends on m/c capacity 4. It is manually print

5. Capacity is 9 colors 5. Variety colors print

Difference between Automatic Print & Hand Print

Printing methods

Digital printing

Ink-jet printing

Heat-transfer printing

Design transferred to fabric from specially printed paper by heat & pressure

Electrostatic printing

Prepared screen covered with powdered dye; passes through electric field & pulled onto material

Foil printing

Adhesive applied to fabric, foil heated on heat transfer press & bonds to adhesive pattern

Stencil printing

Separate pattern cut for each color, color is applied in thick paste or sprayed on with air gun

Factors Affecting Cost of Printing

1. Size of printing

2. Number of color of printing

3. Any grading of size of printing from size to size

4. Any restriction/selection of use of dyes and chemicals

5. Lab test requirement

6. Wash sustainability

7. Tolerance in placement of print art-work

8. Tolerance in color shade variation

9. Place of printing

10. Type of printing

Preparation of the fabric to be printed

Preparation of the print paste

Making an impression of the print paste on the fabric

Drying of the printed fabric

Steaming of the printed fabric

After treatments (soaping etc)

Steps of printing

Design

Expose

Color

Develop sample

Steps of printing section

Block Printing

It is the oldest and simplest way of printing

In this method a wooden block with a raised pattern on the surface was dipped into

the printing colorant and then pressed face down on to fabric.

The desired pattern was obtained by repeating the process using different colors.

Generally the wooden block is carved out of hand

Printing is done manually

BLOCK PRINTING

BLOCK PRINTING

ADVANTAGES

1. Simple method of printing

2. No expensive equipment required

3. No limitation in repeat of size of style

4. Prints produced have great decorative value and stamp of craftsmanship

DISADVANTAGES

1. Involves much manual work

2. Method is slow and therefore low output

3. Good skilled labors needed for multi color design

4. Fine and delicate designs hard to produce

ROLLER PRINTING M/C

Diagram of roller printing m/c

ROLLER PRINTING

ADVANTAGES

1. Large quantities of fabric at the rate of 914-3658m per hour can be printed.

2. Faulty joints or joint marks are absent.

3. Fine sharp outlines and good prints can be obtained which is difficult to get in block

printing.

DISADVANTAGES

1. Not economical for short run of fabrics.

2. Difficult to produce blotch designs.

3. Repeat of design limited to the size of the rollers.

4. Setup cost of roller printing m/c is high

STENCIL PRINTING

It is one of the oldest way of printing.

In it color is applied to the fabric by brushing or spraying the interstices of a pattern

cut out from a flat sheet of metal or waterproof paper or plastic sheet or laminated

sheet.

A stencil is prepared by cutting out a design from a flat sheet of paper, metal, or

plastic.

A simple stencil design

Example of stencil printing

STENCIL PRINTING

ADVANTAGES

1. Simple and cost effective.

2. Stencils can be made rapidly and can be used for small orders.

3. Color combination is good in it.

DISADVANTAGES

1. Good design is difficult to obtain.

2. Process is laborious.

3. Not suitable for large scale production.

SCREEN PRINTING

It involves the application of the printing paste through a fine screen placed in

contact with the fabric to be printed.

A design is created in reverse on the screen by blocking areas of the screen with a

material such as an opaque paint.

The screen is then placed over the fabric and the printing paste is forced through the

open areas of the screen using a flexible synthetic rubber or steel blade known as a

squeegee.

PROCESS OF SCREEN PRITING

SCREEN PAPER SIDE SCREEN SQUEEZE SIDE

ORIGINAL PRINT PRINT ON FABRIC

SCREEN PRINTING

ADVANTAGES

1. Simple and cost effective.

2. Quick pattern making

3. 16 colors can be used in a design.

4. Sharp lines and features easily produced.

DISADVANTAGES

1. For high production large no. of tables required.

2. Delicate shading difficult to obtain.

3. Screen clogging may be there in fine areas.

FLAT-SCREEN PRINTING

It is the advanced version of screen printing by using automatic m/c to do work

It consists of printing table, conveyor belt, number of screens, mechanism to print

on the fabric, etc.

First the fabric is brought on the printing table through a feeding arrangement and it

is gummed to the conveyor belt on the table

Conveyor brings fabric periodically under screen and stops while the screen are

lowered on the required parts of the fabric.

Printing paste is distributed throughout the full length of the screen.

The squeeze is pressed to the screen .

One or more strokes of the squeeze ensure simultaneous printing of the pattern by

the common action of all screens which applies printing paste as required by the

color in the design.

FLAT-SCREEN PRINTING M/C

FLAT SCREEN PRINTING

ADVANTAGES

1. Greater production than manual screen printing

2. Printing with different repeat can be made easily

3. Good print is obtained

DISADVANTAGES

1. A big setup required for more number of screens

2. Prints with more colors may not be possible

3. Printing paste not evenly controlled

This process involves a print paste (like a thick paint) that is applied to an engraved

roller, and the fabric is guided between it and a central cylinder.

The pressure of the roller and central cylinder forces the print paste into the fabric.

Because of the high quality it can achieve, roller printing is the most appealing method

of printing designer and fashion apparel fabrics.

Long runs of the same fabric design are produced on a roller print cylinder machine

operating at speeds between 50 and 100 yards a minute. As many as 10 different colors

can be printed in one continuous operation, but each colour must have a separate roller.

The design is cut into the surface of copper rollers; by varying the depth of the

engraving on the roller the shade depth can be altered.

Rotary Screen Printing

Sharpness of line and fine detail can be achieved this way. A typical printing machine

has a large padded drum or cylinder, which is surrounded by a series of copper rollers,

each with its own dye trough and doctor blade that scrapes away excess dye.

The tubular screens rotate at the same velocity as the fabric, the print paste is

distributed inside a tubular screen, which is forced into the fabric as it is pressed

between the screen and a printing blanket (a continuous rubber belt). It picks up colour

from the engraved area of each roller in sequence.

The printed cloth is dried immediately and conveyed to an oven that sets the dye.

Knitted fabric is mostly printed in this method as it does not pull or stretch the fabric.

Rotary Screen Printing Process

Screen mode (50-60 min dryer temp 70 c)

Exposing m\c

Cold water (5 min)

After them spray gun develop

Dryer (30-40 min)

Re-wash

Dryer (20 min)

Re-expose (20 min)

Hard & applied.

Design complete

Steps in design to screen:-

TRANSFER PRINTING

It is a indirect method of printing in which dyes are transferred from paper to a

thermoplastic fabric under controlled conditions of temperature, time and pressure.

The image is first engraved on a copper plate.

Then pigment is applied on these plates.

The image is then transferred to a piece of paper, with a layer of glue applied .

This is then placed on the fabric and heat and pressure applied which fixes the print

onto fabric.

TRANSFER PRINTING

ADVANTAGES

1. Operation is simple and no expensive m/c is required.

2. No after treatment of fabric required

3. Print on fabric is of excellent quality

DISADVANTAGES

1. Process applicable to synthetic fabric like polyester .

2. Color range is limited.

3. Cost of printed paper high.

4. Not economical for small orders.

Dye sublimation allows photo lab quality picture printing. During the dye sublimation

printing process, an image is digitally printed in reverse with dye sublimation toners or inks

onto media.

That image is then placed on top of a fabric and subjected to high heat and pressure to

form a heat press.

The dye sublimation toners or inks sublimate the inks go from a solid state to a gaseous

state without becoming liquid in between and flow into the fabric, dyeing the threads.

This creates a gentle gradation of colour and does not distort or fade over time.

Dye Sublimination Printing

RESIST PRINTING

There are two types of resist printing

1) BATIK PRINTING

2) TIE & DIE PRINTING

BATIK PRINTING

Originated on island of Java and is a cottage based industry.

Batik is derived from word AMBATIK

The resist-dyeing process, whereby designs are made with wax on a fabric which is

subsequently immersed in a dye to absorb the color on the unwaxed portions, is

known as batik printing.

Special feature is the fine lines of color running irregularly across the fabric.

Dyeing fabrics

Industrially-produced Batik

HOW IS IT DONE?

Gum, wax-resist paste or resin is printed on the fabric from hot rollers

Fabric is dyed

Heat finished to remove surplus gum or wax and fix the dye

Alternatively, batik patterns can be printed on fabric from engraved rollers using photographic methods or CAD/CAM

Hand-produced Batik

HOW IS IT DONE?

A design is drawn on fabric with melted wax using a brush or tjanting and left to harden, fabric is then brush or dip dyed and the wax

melted off using an iron. The dye resists penetrating the fabric under the wax leaving a

patterned fabric.

BATIK PRINTING

ADVANTAGES

Gives a good artistic effect

Cheap printing

Greater artistic design

Fabric has a rich and graceful

appearance

DISADVANTAGES

Laborious

Time taking

Cracking effect

Dye should be applied at low

temperature than wax.

A resist method of dying where fabric of finished garments are either

twisted, knotted, gathered or crumpled and then bound with string or

elastic bands before dyeing.

Produces a variety of patterns. Garments made using tie dye come in

and out of fashion.

TIE & DYE

It is same as that of batik printing but here the dye is resisted by knots that are tied

in the cloth before it is immersed in dye bath.

The outside of the knotted portion is dyed, but inside is not penetrated if the knot is

firmly tied.

This gives a characteristic blurred or mottled effect .

ADVANTAGE

Interesting design created on fabric

No m/c cost is there

DISADVANTAGE

Costly

Laborious

Time taking

Skilled labour required

Burnout Printing

Burn-out textiles is a technique used to develop raised designs on fabric surface. This is

primarily being done in fabrics with at least 2 different fibre content i.e. Cotton-

Polyester, Silk-Rayon etc. Here one fibre component is being dissolved thru chemical

reactions while the other content remains intact giving away raised illusion designs.

1. This involves printing with a chemical that will destroy the fiber in the patterned design print area.

2. In fabrics that are made with blended yarns, the burn-out chemical will destroy one fiber and leave the other undamaged. Unusual and interesting fabrics can be created by this method.

Burn-out Prints

Tiny particles of fiber are made to adhere to a fabric surface in conformance to aparticular design. Rayon and nylon fibers are typically used for flocking.

The ability of flocked fibers to withstand dry cleaning and/or laundry depends onthe adhesive. Adhesives with excellent fastness to cleaning processes are used.

Flock Prints

Puff print

Foil print

Flock printDuplex Prints

Marketing Printing - Digital Printing

Iris Graphics

STORK

Toxot Imaje

Jemtex

STORK

Epson

Konica

Xaar

Spectra

Hewlet Packard

Canon

Lexmark

Ink-jet systems

Continuous flow Drop-on-demand (DOD)

Binarydeflection

Multipledeflection

Mechanical

Piezo - activatedThermic

"Bubble Jet"

Differences in the selection and generation of droplets

Ink-jet systems

Lighter Print Faults in Textile Screen Printing on Fabric:

Lighter shades on Selvedge and gradually deeper towards the other.

In the middle of the fabric and darker towards the selvedges.

While using large amount of foam.

Due to uneven application of Gum.

Darker Screen Printing faults:

May be obtained irregularly throughout the fabric.

If a soft table is used on a hard table surface.

If a hard squeeze is used on a soft table surface.

Deep stripes along the warp.

Very small specs of color on the ground (Unprinted Portion).

Screen may get clogged during working.

Difficulties in printing:

Printing faults:

1. Print color shadin

2. Print slarted

3. Color spot

4. Bleeding

5. Print wrong

6. Print burn

7. Air hole

8. Print bubble

9. Print missing

10. Wrong place

11. Not properly attached

12. Hand feels

13. Migration

14. Dirty mark

15. Uneven shade

16. Shade variation

17. Print sticky

18. Print not coverage

19. Print gap

20. Print over

21. Wrong side

22. Color wrong

23. Size mistake

24. Bunoledle card mistake

25.Fabric h

26.Fabric shade

27.Crease mark

28. Oil spot

29. Fabric burn

30.Needle mark

31. Cutting problem

32. Sticker wrong

33. Dye migration

34.Yarn hole

35. Yarn contamination

36. Fly yarn.

Thank you