Experiment no: 03.

Name of the Experiment:

Pigment printing of polyester fabric.

Introduction:

Textile printing is one kind of localized dyeing that is dyes or pigments are applied locally or discontinuously to produce various design on the fabric. Printing has particular effect of color on the fabric according to design. In printing, one side is printed of the fabric.

Theory:

Pigment printing may be defined as “insoluble pigments, which have no affinity for the fiber, are fixed onto the textile substrate with a binding agent in the pattern required.” There are two pigment printing methods. One is electron beam irradiation method and another one is conventional thermal printing method.

Apparatus:

Biker Thermometer Pipette Mug Sample etc

Recipe:

Pigment=3-4 parts

Binder=40 parts

Fixer=4-5 parts

Emulsifier=10 parts

H2O=Rest

PH≤5

Thickener=40 parts.

Thickener preparation recipe:

Fine gum=3gm

Water (H2O) =50 ml.

Function of chemicals:

Binder:binder is a film forming substance made up of long chain macro moles,which is applied to the three dimensionally linked network.binders are those adhesive type coating foaming polymeric materials which sticks pigment particle on fabric surface.It forms a very thin invisible film on fabric surface during curing.Under this pigment particles are remained sticked.it is used to fix the pigment with fabric,it also make a bond.Fixer:It is used to convert a soluble dye in to an insoluble form on the fabric after printing.Emulsifier:It promotes formation of a stable emulsion when two unmixable liquids are combined with mechanical agitation.Thickner:It is used to control the viscosity of printing paste.It prevents the dyes from spreadingout on the cloth.

Working procedure:

At first we have produced thickener by taking require amount (from recipe) of fine gum and water.In another mug, we produced another paste for printing by adding Pigment, binder, fixer, emulsion according to the recipe requirement.After that, we took the thickener (40 parts) and mixed with the paste.We got the final printing paste and this printing paste was ready for use on the sample.Before starting printing, we cleaned the screen and squeeze for better printing.We bended the squeeze at 45° angle during printing for smooth distribution of printing paste on the screen.We have used 3-4 strokes during printing.Finally we got a printed fabric and send for curing process.

Fabric sample-

After treatment(curing):

The printed sample is taken and dried it to get a final printed fabric. For that we have used 160° C - 180° C temperature for about 30sec- 1 minute.

Precaution:

We were very careful during thickener making. We have taken all the chemicals at accurate amount. We placed the sample under the screen carefully We dried the printed fabric for better result.

Conclusion:

Pigment printing is less expensive and easy applicable. By doing this experiment now we know about pigment and how to dye of cotton fabric with pigments. This experiment is very important and I think it will be helpful for our job life.