Application of Protective Finishes on Denim and Analysis …
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2.2 Determination of Anti-Microbial
The test method AATCC 100 was used for testing the growth of microorganisms. The
microorganisms were grown in liquid culture and this concentration of test microorganism was standardized. The microbial culture was diluted in a sterile nutritive
solution. Control and test fabric swatches were inoculated in this liquid. The inoculation was performed such that the microbial suspension touches the fabric. Bacteria
levels on both control and test fabric were determined at “time zero”, that is “B” by
elution in a large volume of neutralizing broth, followed by dilution and plating. A
control was run to verify that the neutralization/elution method effectively neutralized
the anti-microbial agent in fabric. Additional inoculated control and test fabric were
allowed to incubate, undisturbed in sealed jars for 24 h, that is, “A”. After incubation, microbial concentrations were determined. Note: For AATCC 100, percentage
reduction: R = 100 (B – A/B), where “B” and “A” are the number of bacteria per
sample observed before and after 24 h of incubation, respectively.
2.3 Determination of Weight Add-On
The weight of the samples was taken before and after the application of finish. The
increase in weight gave the percentage add-on in weight. The concentration of antimicrobial finish was increased with the increase in weight of fabric, as there is more
absorption capacity.
2.4 Determination of Percentage Shrinkage
The standard ISO 6330:2012 specifies domestic washing and drying procedures for
textile testing. The procedure was applicable to textile fabrics, garments, or the textile
articles, which are subjected to appropriate combinations of domestic washing and
drying procedures.
2.5 Determination of Fabric Stiffness
The bending length was measured on Shirley’s stiffness tester, in accordance with
ASTM D1388-96 test method.
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2.2 Determination of Anti-Microbial
The test method AATCC 100 was used for testing the growth of microorganisms. The
microorganisms were grown in liquid culture and this concentration of test microorganism was standardized. The microbial culture was diluted in a sterile nutritive
solution. Control and test fabric swatches were inoculated in this liquid. The inoculation was performed such that the microbial suspension touches the fabric. Bacteria
levels on both control and test fabric were determined at “time zero”, that is “B” by
elution in a large volume of neutralizing broth, followed by dilution and plating. A
control was run to verify that the neutralization/elution method effectively neutralized
the anti-microbial agent in fabric. Additional inoculated control and test fabric were
allowed to incubate, undisturbed in sealed jars for 24 h, that is, “A”. After incubation, microbial concentrations were determined. Note: For AATCC 100, percentage
reduction: R = 100 (B – A/B), where “B” and “A” are the number of bacteria per
sample observed before and after 24 h of incubation, respectively.
2.3 Determination of Weight Add-On
The weight of the samples was taken before and after the application of finish. The
increase in weight gave the percentage add-on in weight. The concentration of antimicrobial finish was increased with the increase in weight of fabric, as there is more
absorption capacity.
2.4 Determination of Percentage Shrinkage
The standard ISO 6330:2012 specifies domestic washing and drying procedures for
textile testing. The procedure was applicable to textile fabrics, garments, or the textile
articles, which are subjected to appropriate combinations of domestic washing and
drying procedures.
2.5 Determination of Fabric Stiffness
The bending length was measured on Shirley’s stiffness tester, in accordance with
ASTM D1388-96 test method.