Overview on Textile Printing

Printing Technique 

Maruf Mahfuz (WUB), Mohammad Asif Hossain (BUTex), 

Kazi Sabbir Ahmad (AUST), Mosfiqur Rahman (EWU),
 Ruhul Amin (NTEC)

Management Trainee Officer

Pride Group, Savar Dhaka.

Introduction 

Textile printing is the process of applying color to fabric in definite patterns or designs. 

In properly printed fabrics the color is bonded with the fiber, so as to resist washing and friction. 

Textile printing is related to dyeing but, whereas in dyeing proper the whole fabric is uniformly covered with one color, in printing one or more colors are applied to it in certain parts only, and in sharply defined patterns.

History of Printing

The exact origin of textile printing is difficult to determine. However, a number of early civilizations developed various techniques for imparting color and design to textile garments. Batik is a modern art form for developing unique dyed patterns on textile fabrics very similar to textile printing. Batik is characterized by unique patterns and color combinations as well as the appearance of fracture lines due to the cracking of the wax during the dyeing process. Batik is derived from the Japanese term, “Ambatik,” which means “dabbing,” “writing,” or “drawing.” In Egypt, records from 23-79 AD describe a hot wax technique similar to batik. The early Egyptians also used ink-carved designs on the ends of wooden cylinders to print on fabrics as early as 400 AD. In Europe, the earliest evidence of textile printing is provided by a wooden block discovered in France dated to the end of the 14th century. The family name “Tuchdruckers” or “textile printers” was well known in Germany by 1440. In the United States, woodcut block printing was practiced in Massachusetts, New Jersey, and Pennsylvania by the 1770’s. A tremendous breakthrough occurred in 1783 when James Bell, a Scotsman, invented engraved roller printing.

Process of Direct printing

In fabric printing, a decorative pattern or design is applied to constructed fabric by roller, flat screen, or rotary screen methods.

Roller Printing

In the roller printing process, print paste 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 for printing designer and fashion apparel fabrics.

Screen printing

In flat screen printing, a screen on which print paste has been applied is lowered onto a section of fabric. A squeezer then moves across the screen, forcing the print paste through the screen and into the fabric.

Rotary Screen printing

In rotary screen printing, tubular screens rotate at the same velocity as the fabric. Print paste distributed inside the tubular screen is forced into the fabric as it is pressed between the screen and a printing blanket (a continuous rubber belt). Rotary screen printing machines are used mostly but not exclusively for bottom weight apparel fabrics or fabric not for apparel use. Host knit fabric is printed by the rotary screen method, because it does not stress (pull or stretch) the fabric during the process.

Screen Preparation 

To be considered:
•Mesh size selection
•Types of printing
•No of color on design
•Area of design
•Uniform tension

•Proper attachment of screen with frame

Color room functions

Factors to be considered for selection of printing technique:

• Color of the Fabric (Dark, Light).
• In case of Dark/ deep color mainly used discharge printing.
• In case of light color pigment print is preferable. In case of flock print on dark color a rubber made base is used.

Printing paste preparation

Pigment printing paste

•BR 1000 (Binder +Thickener)
•Pigment
• Fixing agent (Only for Acid wash, Enzyme wash)

Discharge printing paste

•Flurotex DBC for color discharge
•BW for white Discharge
• RNS powder
•Color

Rubber printing paste

•White 101 for white rubber
•Clear 594 for color rubber
•MK binder

Overview on different Printing

Pigment printing:

Pigments are mainly synthetic organic materials. Pigment printing is done to produce attractive design by applying pigment paste on the fabric surface. Pigments are found in particle state and the particle size range should be in the region of 0.1 – 3 microns. Pigment printing is done with binder system. We know that pigment has no affinity to cotton fabric for this reason binder is required during printing.

Flow chart of pigment printing 

Paste preparation 

↓ 

Table preparation/ Machine preparation 

↓ 

Fabric plaited on the table 

↓ 

Pigment printing paste apply with the help of screen 

↓ 

Curing at 150 ºc (belt speed 5 m/min)

Advantages & Disadvantages of Pigment printing

Advantages  

•Applicable to natural and synthetic fiber.
•Pigment printing is most economical printing process and allows maximum output of goods because of the elimination of washing off, quick sampling and high printing speeds.
•The advantage of pigment printing is that the process can be done without subsequent washing.
•Simple Application Simple technical process without wet after treatment
•Little requirements for machinery equipment

Disadvantage

•Handling properties of the pigment printing is rough because of having excessive cross linking agents.
•During second time printing it has very low effect that is not desirable

Discharge Printing 

Discharge means to remove specific colored area by another color or reducing it by bleaching agent. By this printing process, color is destroyed by one or multiple color. By this process pigment in the fabrics is removed chemically and replace it by another color. The dyed fabrics dyes should be dischargeable during printing process.

Paste preparation (White paste/ Color paste) 

↓ 

Table preparation/ Machine preparation 

↓ 

Fabric plaited on the table 

↓ 

Pigment printing paste apply with the help of screen 

↓ 

Curing at 150 ºc – 180 ºc (belt speed 5 m/min)

Advantages & disadvantages of discharge printing:

Advantages 

It enables light, brighter colors to be obtained on a dark ground.

•Very sharp features like fine outlines, dots, raster etc., can be produced with total clarity.

•Tinting of white pattern on coloured ground (In case of direct style) is avoided by discharge printing.

•The effect, clarity, distinction, richness and aesthetic appeal obtained add value for discharge printing

Disadvantages

•It is an expensive process. Two stage application involved in dyeing or padding and discharge printing.
•Limited choice of ground and motif colours.
• Requires rigid process care that any default will lead to damages.

Rubber Printing

A very common and versatile material that is used to print to garment due to its ability to adhere well to fabric. It can apply to most fabric materials in light or dark colours. The texture feels thick and tensile. A special rubber formulation has to be made in order to apply this print to elastic material.

Rubber printing Process 

Table preparation 

↓ 

Fabric plaited on the table 

↓ 

Rubber printing paste apply with the help of screen 

↓ 

Curing at 150ºc (Belt speed 5 m/min) 

↓ 

Delivery

Plastisol Printing 

PLASTISOL PRINTING PROCESS 

Printing paste preparation 

↓ 

Table preparation 

↓ 

Fabric plaited on the table 

↓ 

High-density paste apply by screen 

↓ 

Curing at 150ºc (belt speed 5m/min) 

↓ 

Delivery 

Advantages & Disadvantages of plastisol printing 

Advantages 

•Plastisol can be left in the screen for extended periods of time without clogging the mesh.
•It is ready to use right out of the container more than 90% of the time.
•In most applications, it can be printed wet-on-wet, which allows for increased production speeds.
•It comes in formulations that can be printed on light and dark color fabrics
•And, in most municipalities, the disposal of waste plastisol is a very simple process.

Disadvantages

•Since Plastisol is a thermoplastic, it will remelt if it comes in contact with anything hot enough. For that reason, plastisol prints cannot be ironed.
•If an iron touches a print, it will smear the ink.
•Plastisol ink also creates an ink film that can be felt with the hand. The higher the opacity of the ink, the greater the hand. This heavy hand is considered a disadvantage at the consumer level.

Characteristics of Different types of Printing 

Process Printing 

Process color printing, is known at four-color process printing, is a method that reproduces finished full-color artwork and photographs. The three primary colors used are cyan (process blue), magenta (process red), and yellow. These inks are translucent and are used to simulate different colors. The "K" in CMYK is black. Black ink is used to create fine detail and strong shadows.

Process printing flow chart 

Paste preparation 

↓ 

Table preparation 

↓ 

Fabric plaited on the table 

↓ 

Printing paste is applied through 4 different screens on the fabric 

↓ 

Curing at 150ºc (belt speed 5m/min) 

↓ 

Delivery

Foil printing

Foil printing is a sublimation transfer printing process. Foil printing is done by the help of paper. Foil paper is solid color which is made by buyer requirement. Printing is done in high temperature and pressure. By this printing process man-made and natural both fabric types can be print.

Foil printing flow chart 

Fabric plaited on the table 

↓ 

Foil gun / Foil paste (Gum)apply by screen 

↓ 

Dry slightly in air temp / Hand dryer 

↓ 

Apply foil paper on the fabric 

↓ 

Heat apply by heat press m/c 150 ºc for 5 sec) 

↓ 

Cooling for 4 sec 

↓ 

Foil paper removed by hand 

↓ 

 Delivery

Flock printing 

Flock printing is done by depositing various flocks on the surface of the fabric. Flocks means small finely cut natural or synthetic fibers. This flocks are applied on an adhesive coated surface for impart a decorative or functional characteristics to the surface of the fabric.

Flock printing flow chart 

Fabric plaited on the table 

↓ 

Apply flock paste with the help of screen 

↓ 

Flock powder apply with the help of flock gun 

↓ 

Manually dry by hanging for 30min 

↓ 

Curing at 180ºc (belt speed 3 

m/min) 

↓ 

Delivery 

↓ 

Brushing 

↓ 

Delivery

Emboss printing 

Emboss printing is not as available as pigment printing, f oil printing, f lock printing or any others dyes printing. It is specially done f or logo making or others decorative purpose. In this printing process, printing is done by embossing the printing paste on the textile materials.

Process flow of puff printing

Paste preparation with puff chemical

↓

Table preparation

↓

Fabric plaited on the table

↓

Apply printing paste by screen (3 times)

↓

Hanging f or 15min

↓

Curing at 150 ºc (belt speed 3m/min)

↓

Delivery

Crack printing

Crack printing is a printing method to produce attractive design on the fabric surf ace. Here rubber is used as the printing paste. It is near similar as rubber printing process but additional crack paste is used before applying rubber printing paste by the screen printer on the cotton fabric. 

Crack printing flow

Print paste preparation with cracking chemical 

↓

Crack paste/clear apply with the help of screen

↓

Dry in air temp or hand dryer m/c (slight)

↓

Printing paste apply with the help of screen

↓

Curing at 150ºc (belt speed 2 m/min)

↓

Delivery

High density:

High density printing is done by more number of stroke to make the printed area thicker during printing. High density printing may be two types: Rubber base high density & Plastisol base high density.

High density printing flow 

Paste preparation 

↓ 

Table preparation 

↓ 

Fabric plaited on the table 

↓ 

Printing paste is applied through screen on the fabric & stroke repeatedly till the design is produced 

↓ 

Curing at 150ºc (belt speed 5m/min) 

↓ 

Delivery

Sublimation

Sublimation is a transfer printing process. It is pigment based printing. Any type of design having greater complexity can easily be developed on the fabric surface. Here, the printed design is transferred from paper to fabric surface through heat pressing. The sublimation printing process is based on CYMK theory.

 

Conclusion: 

The development of modern equipment and colorant technology has enabled textile manufacturers to be able to reproduce highly colored textile designs with excellent colorfastness. This can be performed on a wide variety of fibers and fabric constructions, employing cost effective processes. However, as good as textile-printing technology is today, the processes are continuing to improve. New technologies and new developments in existing methods promise to continue the expansion of the capabilities of textile printing well into the future.