Printing

T

EXTILE

P

RINTING

Textile printing is used to signify the production,

by various means of colored patterns on designs

upon all sorts of textile fiber.

Textile printing is the most important and versatile

of the techniques used to add design, color, and

specialty to textile fabrics.

2 K W M : P rin ti n g

S

TEPS OF

P

RINTING



The basic steps in the printing process are as

follows:



Preparation of the fabric



Preparation of the print paste.

Printing the fabric.



Drying the printed fabric.



Fixation of the printed dye or pigment.

P

RINT PASTE AND ITS INGREDIENTS



Print paste is a viscous solution of printing ingredients

referred below that is used for textile printing. The main

three printing ingredients are:

•

Dyestuff or pigments

•

Thickeners: Thickener can be defined as a substance

used to increase the viscosity of a print paste or other

fluid, in order to control its flow properties.

•

Chemicals and waters: The main types of chemicals

used for textile printing are wetting agents, solvents,

solution acids, dispersing agents, hygroscopic agents,

oxidizing & reducing agents, defoamers, acids, alkalis,

P

LASTISOL VS

. W

ATER

-

BASED

I

NK

 There are two main types of ink that are used for textile

printing.

 Water-based ink utilizes either dyes or pigments in a

suspension with water as the solvent. The evaporation of the water is necessary to set or cure the ink. Plastisol ink is a PVC based system that essentially contains no solvent at all.

Usage Recommendations Plastisol Water-base

T-Shirts/light colors Excellent Excellent T-Shirts/dark colored Good Poor Nylon Jackets Good Poor

Towels Poor Excellent

Yard goods Poor Excellent

S

TYLE OF

P

RINTING



Metal style of printing: In the metal style of printing

fabric is printed with silver or gold solution or

non-removable resins.





Resist Printing: In this method, the fabric is first printed

in a design with a chemical that resists dye. The fabric is

then dyed. The resist will leave the fabric white or some

other color in the print areas. One of the advantages of

this method is that dyes with very high colorfastness can

be used.





Flock Printing: Flock printing is a process in which a

‘flock’ is fixed on to a cloth by means of adhesive to form

printed pattern. It produces a pile or velvety effect on the

fabric similar to form a printed pattern.

S

TYLE OF

P

RINTING



Discharge Printing:

‘Discharge’ means removal and

‘Discharge style’ refers process which can produce a

white or colored effects on a dyed ground by printing

paste containing a chemical capable of removing the

ground color called ‘discharging agents.’ It could be of

two types





White Discharge: the printed part remains

white after destroying the dyed color



Color Discharge: With a dye incorporated in

the print paste which is resistant to discharging agents.

When printed the discharging agents removes the

ground color and at the same time deposit color on the

M

ETHOD OF

P

RINTING

 Block printing: In this method the wooden or metal block with a

negative and raised design (i.e. in relief) is first stamped on the print paste and then on the cloth and an impression of positive design is made on the cloth.

 Screen printing: In hand screen printing the fabric is stretched

out on a long table. The screens are moved methodically along the fabric. When a screen is in position the dye paste is pressed through the open mesh with a squeegee blade.

 Transfer printing: Transfer printing is defined as any process by

which a design is transferred from paper to another substrate. Selected disperse dyes transfer in vapor form to thermoplastic fibers when the printed paper and fabric are brought into close contact in a transfer press at 170°-220°C.

F

LAT BED

S

CREEN PRINTING

F

LAT BED SCREEN

P

RINTING

R

OTARY

S

CREEN PRINTING

R

OTARY

S

CREEN PRINTING

P

IGMENT PRINTING

 In pigment printing, insoluble pigments, which have no affinity

for the fiber, are fixed on to the textile with binding agents in the pattern required.

 Importance of pigment printing

• Pigments, of course, are used for the production of

plain-colored fabrics, but are of much greater importance in printing.

• _{The pigment can be applied to all fibers potentially and it is}

the only coloration to glass fiber, fabric and polyester

• No wet treatment is required, so drying and curing is

applicable to all fiber.

• Extensive color range of highly light fast colors

• _{Possible to produce good combination shades on blended}

fiber in one padding operation

• Application procedure is simple

F

OIL PRINTING

This printing method is based on the use of metallic foil paper of aluminum or copper one. A foil layer is affixed to a certain

material by a heating process.

14 K W M : P rin ti n g

W

ATER BASED GEL PRINT

A rapidly drying aqueous

printing ink containing a gel forming polymer soluble in the ink but which rapidly gels upon application of the ink to a substrate during a printing process. Gel ink gives high gloss ‘wet

looking’ prints that have a three-dimensional feel to

S

PRAY

P

RINTING

A spray gun forces the color through a screen

H

IGH DENSITY PRINTING

 _{High Density printing is the}

process of printing a specially formulated ink through a very thick stencil to achieve a raised, glossy smooth print with very sharp edges.