Although the latest revision of several laundering test methods and procedures by the American Association of Textile Chemists and Colorists (AATCC) defines standard laundering conditions for traditional top-loading machines, many labs also have high-efficiency (HE) washing machines. AATCC offers a standard detergent specifically formulated for use in HE washers.
One of the most visible features of high-efficiency detergents is that they produce less foam or bubbles than traditional detergents. Excess foam interferes with cleaning and, especially, rinsing. Residue build-up in test specimens, ballast, and even the washing machine can lead to inconsistent test results and damage to the washer.
The AATCC HE detergent formula was recently adjusted to produce even less foam, although all active ingredients and performance remain the same. As a standard detergent, the target is to match the performance of mid-tier consumer detergents. Because textile testing typically involves little or no soil and a very small load size, the 50-mL dose of AATCC HE detergent produces even less foam than comparable consumer detergents. It is still important to ensure specimens are thoroughly rinsed before testing.
While traditional detergents should never be used in HE washers, HE detergents can be used in traditional washers. AATCC Laboratory Procedure (LP) 1-2018, Home Laundering: Machine Washing, includes instructions for use of both traditional powder detergent and HE liquid detergent in the Alternate Laundering Procedure for traditional top-loading washing machines. The test report should clearly indicate which detergent was used.
AATCC HE detergent contains no optical brighteners. For colorfastness testing, the optical brighteners present in most consumer detergents can interfere with specimen evaluation. Optical brighteners, also referred to as fluorescent whitening agents (FWAs), absorb light in the ultraviolet (invisible) region of the electromagnetic spectrum, and re-emit it in the blue (visible) region. A white surface treated with an optical brightener emits more visible light than shines on it, making it appear brighter.
AATCC standard reference detergents without optical brightener (WOB) let you assess color change due to the test procedure, without the added influence of brighteners. This makes it easier to determine whether a particular dye or process is suitable for your product. Brighteners do not affect any other textile properties or the detergent’s cleaning performance.
AATCC recently published LP1 provides complete laundering specifications and procedures for traditional top-loading washers, HE top-loading washers and HE front-loading washers. This document replaces Monograph 6.
The “standard” conditions for LP1 and related test methods use a traditional top-loading washer, but several “alternate” options are available for HE washers.