AATCC 191 pdf free download

AATCC 191 pdf free download.Acid Cellulase Enzymes, Effect of: Top Loading Washer.
1. Purpose and Scope
1.1 This test method provides a simple testing procedure to evaluate the effect of acid cellulase enzymes on cellulosics by laundering.
1.2 The evaluations are carried out as listed in Section 8.
1.3 Other cellulase enzymes, i.e., modified acid and neutral types, may be evaluated by this test procedure. However, the concentration, pH, and time should be followed as recommended by the enzyme supplier.
1.4 A specific concentration of enzyme. buffer, and detergent are required in the bath to achieve the desired improvements. Since this test method utilizes an automatic washing machine to simulate the action of rotary drum machines, paddle machines, or jets used in production type operations (that usually operate at low liquor ratios), the concentrations required in this test method are based on grams/liter (gIL), to compensate for the difference in liquor ratios.
2. Principle
2.1 This test method determines the reaction of cellulosic fabrics to treatment with acid cellulase enzymes. Such treatments usually result in improvements in the hand, drape, fuzz and pill appearance of cellulosic fabrics together with the removal of linters and immature/dead cotton fibers. The agitation in the washer simulates the action in rotary drum machines, paddle machines and jets.
3. Terminology
3.1 cellulase enz’4me, n.—an enzyme that attacks cellulose.
4. Safety Precautions
NOTE: These safety precautions are for information purposes only. The precautions are ancillary to the testing procedures and are not intended to be all-inclusive. It is the user’s responsibility to use safe and proper techniques in handling materials in this test method. Manufacturers MUST be consulted for specific details such as material safety data sheets and other manufacturer’s recommendations. All OSHA standards and rules must also be consulted and followed.
4.1 Good laboratory practices should be followed. All chemicals should be handled with care. Wear safety glasses and rubber gloves when working with chemicals. Material Safety Data Sheets should be obtained for all the chemicals used in the method.
4.2 An eyewash/safety shower should be located nearby, and readily accessible in case of an emergency.
5. Apparatus
5.1 Automatic washing machine, (the term top loading washer used in this method is synonymous with an automatic washing machine) (see 10.1).
5.2 Automatic tumble dryer (see 10.1).
5.3 Ballast of 920 x 920 mm (36 x 36 in.) hemmed pieces of bleached cotton sheeting (Wash load ballast type 1), or 50/50 polyester/cotton plain weave (Wash load ballast type 3) (seel0.2 and
10.3).
5.4 Reagents
5.4.1 Non ionic detergent; linear alcohol with 9 moles of ethylene oxide.
5.4.2 Buffer AC, sodium acetate (see
10.3).
6.Test Specimens
6.1 Take four to eight garments, or four to eight full width fabric specimens, 0.9 m (1 yd) in length. It is recommended that the cut edges of fabric specimens be sealed by sewing or some other means.
6.2 Two to four garment/fabric specimens are to be used to run the test cycle with enzyme.
6.3 The other two to four garmentJfabnc specimens are to be used to run through the test cycle without enzyme, for comparison.
7.2 Set the home laundry machine on low, small load (12 gal water), approximately 41 kg (90 lbs.) water and hot wash/cold rinse temperature setting.
7.3 Fill the washer using the regular cycle (12 mins wash cycle).
7.4 Add a nonionic detergent (lIgL); volume 40 mL and weight 40 gm.
7.5 Add sodium acetate buffer (6 gIL), volume 195 mL and weight 240 gm.
7.5.1 Stir well; p1-I 4.5-5.0 (if too high, add acetic acid. pH should not be below 4.5; if so, add caustic, 50%).AATCC 191  pdf download.