WET TESTING OF TEXTILE MATERIALS

Color fastness refers to the resistance of color to fade or bleed of a dyed or printed textile materials to various types of influences e.g.. Factors Affecting the Color Fastness Proper

At first I thanks to Allah who has created us Then I give thanks

to my honorable course instructor Ismat Zerin who teaches us nicely My special thanks also goes to lab instructor Md

Rafiqul Islam who learn us friendly.

number

Name of experiment

1 Color fastness to Perspiration

2 Color fastness to Wash

3 Measuring shrinkage% to Wash

4 Color fastness to Rubbing

5 Dyeing of blended fabric with disperse and reactive

dye (Hot brand)

6 Improvement of color fastness properties

Color fastness is one of the important factors in case of buyers

demand The outstandingly important property of a dyed material is the fastness of the shade of color Color fastness refers to the resistance of color to fade or bleed of a dyed or printed textile materials to various

types of influences e.g water, light, rubbing, washing, perspiration etc

to which they are normally exposed in textile manufacturing and in daily use We have written a lot of articles on color fastness.

Standards of Color Fastness:

1 AATCC (American Association of Textile Chemists and Colorists) technical

manual:

Describes 66 numbers of different color fastness tests

2 SDC (Society of Dyers and Colorists):

In 1927, SDC (Europe) made fastness test committee

3 ISO(International Organization for Standardization):

In 1947, ISO made color sub committee ISO also grades the fastness:

For light fastness: 1~8

For other fastness: 1~5

Factors Affecting the Color Fastness Properties:

•The chemical nature of the fiber For example, cellulosic fibers

dyed with reactive or vat dyes will show good fastness properties Protein fibers dyed with acid mordant and reactive dyes will

achieve good fastness properties and so on That is to say

compatibility of dye with the fiber is very important

•The molecular structure (e.g.) of a dye molecule: If the dye

molecule is larger in size, it will be tightly entrapped inside the

inter-polymer chain space of a fiber Thus the fastness will be

better.

•The manner in which the dye is bonded to the fiber or the

physical form present.

•The amount of dye present in the fiber i.e depth of shade A deep shade will be less fast than a pale or light shade.

•The presence of other chemicals in the material.

•The actual conditions prevailing during exposure

Factors Affecting the Color Fastness Properties:

The textile color fastness is the capacity of a dyed textile to keep its original aspect without loosing color when being wet, washed

or exposed to the light It is one of the main issue of the textile

industry

The fiber type used

The dye and the fiber used have to be compatible A cellulosic fiber and a vat dye will have a good resistance And the polyesters provide a very good result with substantive dyes

The dye type

The way the dye is fixed on the fiber is a factor affecting the textile color fastness: the bigger is the dye molecule the easier it will fix on the fiber There are also insoluble dyes

in water so that the textile color fastness is improved when washing

The tone

The color fastness depends on the dye quantity present on the fiber A neutral or pastel color is more resistant than a dark color

Other chemical elements : the fiber finishing

The textile color fastness can be altered by different finishing used to improve the user comfort

A fastness is a place, such as a castle, which is considered safe because it is difficult to reach or easy to defend against attack This test is designed to determine the degree of color which may be transferred from the surface of a colored fabric to a specify test cloth for rubbing (which could be dry and Wet)

Experiment Name: - Color Fastness to

perspiration.

Continuous contact with the human perspiration also affects the fastness of some the dyed fabrics In fact the perspiration is found to be either slightly alkaline or acidic in nature When fabric is subjected to this alkaline or acidic perspiration continuously some times the tone and depth of the dyed shade gets affected

We can see how this change can be tested by artificially simulating the

the perspirometer.

Dip the fabric in the above recipe for

30 minutes at 30C; allow it dwell for 14hours under 4.5 kg weight of the

perspirometer.

Experiment Name: - Color Fastness to perspiration.

Recipe

Acid Bath

Alkali Bath

L-Histidine mono-hydrochloride mono-hydrate

Before knowing about the Color Fastness to perspiration you

must have to know about Color Fastness to Wash and Color

Fastness to Rubbing.

Measurement Principle

The garments a\which come into contact with the body where perspiration is heavy may suffer serious local discoloration This test is intended to determine the resistance of color of dyed

textile to the action of acidic and alkaline perspiration.

Equipment For Fastness Measurement

1 Perspiration tester

2 Oven, Maintained at 37+-2 Degree centigrade

3 Multifiber test fabric

4 Grey scale

5 Color matching chamber

6 Acidic and Alkaline solution

7 Glass or Acrylic plat3e 8 Weight.

Sample size will be 10 CM * 4 CM

Test Procedure

1 Wet-o0ut the composite test sample in mentioned alkaline or acidic solution at room temperature The Material ration will be 1:50 and leave for 30 minutes.

2 Pour off excess solution and place the composite sample

between two glass plate or acrylic plate under a pressure of 4.5

KG and place in a oven for 4 hours at 37+- and 2 degree

centigrade temperature.

3 Remove the specimen and hang to dry in warn air not

exceeding 60 Degree centigrade.

Evaluation

Evaluation is done by Grey scale in a dyed color matching

cabinet and rate from 1 to 5.

Description of Test Test result

Test method Temp 0 C Time Steel balls Chemicals

Description of test Test result

Color change in shade 2

Experiment Name: -Color fastness

Color fastness against rubbing /Crocking

In order to determine the color fastness of dyed or printed textiles or

leather, this test is used for the determination of color fastness

against rubbing, either under dry or under wet conditions.

Features of Crockmeter:

1.To determine the Color Fastness of Textiles.

2.The equipment consists of a counter

3.It is provided with a flat peg

4.It also consists of an operating handle

5.Tests the color fastness of the textile in a very accurate manner

6.It gives not only accurate but quick results also

There are two test methods for rubbing fastness.

1.ISO-105-X12

2.AATCC-08

In ISO-105-X12 the wet pickup of the rubbing cloth is 100% While in

AATCC-08 the wet Pickup of the rubbing cloth is 65%.We check rubbing by Dry and Wet methods In wet rubbing we wet the rubbing cloth according to test

method and give rating by comparing the Staining with the gray scale

Similarly for dry rubbing we check the rubbing with dry rubbing cloth and

compare the staining With gray scale for ratings.Color Fastness to rubbing is a main test which is always required for every colored fabric either it is Printed or dyed

If the color fastness to rubbing is good then its other properties like Washing

fastness and durability etc improves automatically because the rubbing is a method to check the fixation of the color on the fabric So if the fixation is good its washing properties will be good

Rubbing Fastness depends on:

Nature of the Color

Depth of the Shade

Construction of the Fabric Nature of the color Each color either it is pigment

, Reactive ,Disperse or direct has its own fastness properties to rubbing There are some colors like black, Red ,Burgundy ,Navy blue which have poor Color fastness properties because of their chemical structure.

Like Black color is a carbon base color and the particle size of carbon is large than the other colors that's why its rubbing properties are poor Similarly red

and blue are in the same case So to improve the color fastness we add more binder to improve the fastness properties of these colors It doesn't mean that

we can not achieve the best results with these colors The required results can achieve but production cost will be increase On the other hand the construction

of the fabric also effects the fastness properties.

If the rubbing fastness on 100.80/40.40 is 3 on the gray scale it will be 2-3 on 52.52/22.22 with the same printing parameters So always keep in mind these effects during finalize the required parameters with your customer

Always Check

Quality construction

Color

Depth of the Color

End Use of the product

Specifications of Crockmeter:

Diameter of the Rubbing Finger : 16 mm & 25 mm

Load on the Finger : 9 N & 20 N

Size of Crocking Cloth : (5 x 5) Cms & (7 x7) cms

Length of the Traverse : 100 ±5 mm

Counter (Re-settable) : 4-Digit Counter

Size of Test Specimen : 25 x 5 Cm

Overall Dimension of the Unit : 600 (W) x 190 (D) x 200 (H) mm

Net Weight of the Unit : 4 Kg (9 lbs.)

Construction : Cold-rolled steel

Working Principle of Crockmeter:

The crockmeter consists of a rigid flat metallic platform on which the test specimen can be held firmly and a abrading finger which rubs against it under a specified load

The platform is fixed over the base of the equipment and lies in a horizontal plane

The test specimen is held firmly over an abrasive paper which is pasted on the upper face of the platform, with the help of two pins holding it at both ends

The abrading finger has a flat circular rubbing face which is covered with 4 piece of white

abradant fabric during the test

The abradant fabrics picks up color lost by the test specimen during rubbing

It is held over the finger with the help of a tapered ring.

Motion to the finger is given through a reciprocating arm with runs an two ball bearings to

minimize friction and to apply a uniform load on the finger

The arm is moved by a manually operated crank and connecting lin The equipment is finished in dark metallic paint and bright chrome plating to give it a corrosion resistant finish

Some time we may improve the light fastness properties by natural sunlight If

we get the LF grade 2-3, then we make light fastness improvement by the sample with the solution of 1% detergent washing to get sample light also remove unfixed dyes Then we dry it in the present of sunlight for 12-20 hours After this if we test LF may get 3-4 rating it is only for sample improvement

which is already formed garments

Improvement Fastnesses and Color Strength Of

Pigment Printed Textile Fabric by plasma treatment

Fastness of treated samples was also higher than untreated fabrics because of

improving bonding strength to the binder At the same time, more color and dry rubbing fastness can be obtained with high treatment power argon plasma treatment Therefore,

we recommend proper argon or air plasma treatment to improve the functionality of

the textile fibers and also fabrics We may improve of fastnesses and color strength of pigment printed textile fabrics

To improve fastness and color strength of the polyester fabrics, atmospheric plasma

treatment was used Polyester fabric was treated with argon or air plasma at

atmospheric pressure, and plasma pretreatment effect on the pigment printing was

evaluated A printing paste comprising synthetic thickener, binder, and pigment was

applied using a flat screen printing technique The fabric was then dried and exposed to heat The cured prints were evaluated for color property, color fastness to

washing, and dry/wet rubbing The effects of atmospheric plasma treatments were

evaluated by XPS, SEM and AFM When the properties of atmospheric plasma treated samples were compared to those of untreated sample, higher K/S values were obtained Also, the fastness of treated samples increased between ½ and 1 point

Plasma treatments are ecologic, and can replace some finishing steps of textile

materials Plasma is produced by accelerating a gas via an electric field Gas atoms are ionized, and free electrons are produced Properties obtained with plasma are

dependent on plasma parameters such as gas, discharge power, pressure, and

electrical characteristics of the gas Plasma is the physicochemical treatment, and

generally is used for changing surface properties of polymers or the other

materials without any marked change in the bulk structure of the materials, because

plasma only modifies outermost layers During a plasma treatment, several concurrent processes may occur at the plasma-polymer interface, depending on the chemical and physical characteristics of the plasma itself As is well known, plasma treatment has two effects on the fiber surface One is physical etching, which occurs when an inert gas, such as argon, is used to modify the surface The other is chemical graft, which occurs when some polar radicals, such as oxygen and nitrogen, are induced to functionalize the surfaces of fibers Crosslinking of radical and excited surface species may also

contribute to the modification of the polymer surface structure

Among the surface properties textile materials which can be improved with the use of the plasma are wetability and quality of dyeing and printing

To achieve sufficient dyestuff adhesion and thus a satisfactory printing result,

atmospheric plasma treatment has been applied to textile materials

Standard soap 2g/L M: L 1:50 Time 35 min Temp 500c

Sample size:

Dimensional stability to wash:

Final (after wash) length-Original (before wash) ×100Original (before wash) length

For warp=33-35/35×100

=-5.75For weft=35.5-35/35×100

=1.42Result:

Warp=-5.75 % shrinkageWeft=+1.42% shrinkage

50 cm

NAME OF THE EXPERIMENT: DYEING OF BLENDED FABRIC (35×65) WITH DISPERSE DYE & REACTIVE DYE

Recipe of polyester part:

Disperse dye (blue) ―3% (OWF)

Calculation:-Sample weight – 20 gm

Total liquor =20×20=400ccAmount of Dye (blue) =13×3/100=.39gmAmount of dispersing agent=400×1.5/1000=0.27gmAmount of carrier =400×1/1000=0.4gmAmount of acetic acid -400×0.5/100=2ccAmount of additional water=400-(0.4+0.2) =399.4cc

Recipe of Cotton part:

Reactive dye (Blue) ―3% Leveling agent ―1g/L Common salt ―70g/L Soda ash ―18g/L M:L ―1:20 Time ―60 min Temp ―900c

Dyeing curve

Amount of soda ash=400×8/1000=3.2gm

Amount of additional water=400-0.4=399.6cc

EXPERIMENT NAME: -FIBER COMPOSITION.

 Acrylic fiber is dissolved D.M.F in 5 min boil.

 Polyester fabric is dissolved phenol in 5 min boil.

 Cotton fabric is dissolved 75% H2SO4 with 20 boil at room temp.

 Wool fabric is dissolved 5% NaOH with 10 min boil.

 Nylon fabric is dissolved HCl with 10 min boil at