Introduction of Textile Printing

Introduction of Textile Printing

 Printing is one kind of dyeing. When different types of color used to make a particular design on the textile goods is called printing. N... 8:05 AM

 Printing is one kind of dyeing. When different types of color used to make a particular design on the textile goods is called printing. Normally printing is performed on the textile goods in dry condition.

Flow Chart of Printing:

Grey Cloth

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Brushing and Shearing

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Singeing

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Desizing

↓

Scouring

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Bleaching

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Mercerizing

↓

Stentering

↓

Washing

↓

Drying

↓

Winding/Beaming

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Printing

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Finishing

Printing Methods:

Printing effect is performed by using some instruments like screen, roller, block etc. The procedure of creating printing effect according to the design by using different types of instrument is called method of printing. The methods used for printing is given below:

1)      Block printing method

2)      Flat press printing method

3)      Stencile printing method / Spray printing method

4)      Screen printing method

5)      Roller printing method

6)      Transfer printing method

7)      Flock printing method

8)      Engraved roller printing method

9)      Batik printing method

10)   Photographic printing method

Style of Printing:

Sometimes we used various types of technique in different printing methods to perform the printing effect easily. This effect of printing is called style of printing. Style of printing mostly depends on the behavior of the dye and chemicals and the material to be printed. Style of printing can be divided into following groups:

1)      Direct style of printing

2)      Dyed style of printing

3)      Azoic style of printing

4)      Metal style of printing

5)      Block style of printing

6)      Crepe or Crepon style of printing

7)      Printing of Lining

8)      Discharge style of printing:

a)      White Discharge style of printing

b)      Color Discharge style of printing

9)      Resist Style of printing

10)   Raised style of printing

Ingredients of Printing:

It is required to produce printing pest before printing. A good printing pest is mainly responsible for good printing effect. So it is very important to make a printing pest carefully. There are different ingredients used in printing pest for different purposes. Generally following ingredients are used in printing pest:

•  Dye stuffs or pigment
• Wetting agent
• Thickener
• Solvents Dispersing agents
• Defoaming agents
• Oxidizing and reducing agent
• Catalyst and oxygen carrier
• Acid and alkali
• Carrier and swelling agent

Steps in printing process:

•     Preparation of print paste
•     Printing of fabric
•     Drying
•     Fixation of dyestuff
•     Washing

Difference between dyeing and printing:

Dyeing	Printing
The process by which a textile material is changed physically or chemically so that it looks mono uniform colored is called dyeing.	When different types of color used to make a particular design on the textile goods is called printing.
In dyeing process, the goods dyed is one color uniformly all over the fabric.	In printing process, color is applied according to the design only.
Dyeing is performed in wet condition.	Printing is performed in dry condition.
Fiber, Yarn and fabric are used for dyeing.	Only fabric is used for printing.
For dyeing there is no design.	For printing there is a particular design.
Only one color is generally used in dyeing process.	One or more colors are used in printing process.
A particular temperature is maintain in dyeing process.	There is no particular temperature controlling system in printing.
Thickener is not used in dyeing process.	Thickener must be used in printing process.
The density of dye solution is low.	The density of dye solution is high.
Generally after dyeing , steaming and curing are not required.	After printing , steaming and curing is must for fixing the dye molecules to the goods.
Dyed fabric is respectively soft in feeling.	Printed fabrics is respectively harsh in feeling.
Respectively low cost.	Respectively high cost.
There is no localized application.	There is localized application.
Much amount of water is required.	Less amount of water is used.
Liquor ratio is high.	Liquor ratio is less.

Automatic Flat Screen Printing:

A.      Approximately 17% of printed goods.

B.      Advantages

a.       Large repeats

b.      Multiple strokes for pile fabrics

C.      Disadvantages

a.       Slow

b.      No continuous patterns

Rotary Screen Printing:

A.      Approximately 50% of printed goods

B.      Advantages

a.       Fast

b.      Quick changeover of patterns

c.       Continuous patterns

C.      Disadvantages

a.       Design limitations

b.      Small repeats

Engraved Roller Printing:

A.      Approximately 26% of printed goods

B.      Advantages

a.       High design capability

                                                                 i.      Fine detail

                                                               ii.      Multiple tones

C.      Disadvantages

a.       Copper cylinders very expensive

b.      Not economical for short runs

c.       Requires highly skilled workers

Heat Transfer Printing:

A.      Approximately 7% of printed goods

B.      Advantages

a.       High quality prints

b.      Fewer seconds

c.       Economical for short runs

d.      Practically pollution free

C.      Disadvantages

a.       Slow

b.      Primarily only for polyester

Thickener:

Thickener or Gummy Substance:

Thickener is used in textile printing which is a main part of high molecular weight compound giving viscose paste in water. This imparts stickiness and plasticity to the printing paste so that it can be applied to a fabric surface without color spreading. All about 50% to above amount is used to prepare a printing paste.

• Function of Thickener:
• It is soluble in water.
• It is comparatively cheaper and available in the market.
•  It has great attractive towards dyestuffs i.e it acts as a dye carrier.
•  It also has viscosity properties for binding.
• It will not react with any dyestuffs or chemical.
•  It bears physical and chemical stability.
• It can be easily removed or withdrawn after printing.
• It prevents bleeding effects and retain the surface of print design.

Finishing:

Finishing Progress:

The treatment applied to the textile goods after dyeing and printing process is normally called finishing process.

Objects of Finishing:

1.         I   To increase the attractiveness of fabric.
2.                     To increase the service ability
3.             To increase the beauty and glitter ness of the fabric.
4.                     To increase the fineness and to ensure smoothness.
5.                   To ensure softness of the fabric.
6.                  To free from hairiness of the fabric.
7.             To increase attractiveness to the fabrics paying customers.

Finishing agents:

Starch, gum, glow, dextrin, china clay, epsum salt, gypsums salt, glycerol, soap, soluble oil, etc. were the finishing agent in previous time. Now long chain fatty acid compound, synthetic resin, cellulose derivatives, quandary ammonium compound etc. are using as finishing agents.