Greying Tests

Ballast soil for redeposition/greying tests

„Soil makes a difference!“

What is true for stain removal testing is even more true for assessing soil redeposition or rather: whiteness maintenance performance. Existing ballast soil systems with total soil quantities as for single wash tests may be used for such testing, but appear to require too many wash cycles to obtain significant results. An ideal redeposition test system replicates‚ ’real’ greying levels with less wash cycles:
„Accelerate don’t exaggerate!“

For many years there has been no commonly agreed test protocol for assessing whiteness maintenance except the A.I.S.E. minimum test protocol which specifies the use of wfk SBL 2004 as soil ballast, dosed as for stain removal testing. However, the common experience (at least to our knowledge) is that the resulting soil level in the wash liquor is not sufficient for accelerated greying tests, the approach therefore of very limited suitability.

The demand for a better suiting whiteness maintenance test system with an improved greying ballast soil was obvious. To find the right solution was a challenge but in cooperation and with the expertise of the member companies of the wfk group we developed a promising Greying Ballast Soil, wfk GBS 2020.

The properties of our GBS 2020 are as follows:

• Greying ballast soil for reliable results after a short number of washing cycles
• Differentiation between products from different product categories and within one product category
• Simple test with AISE standard load, whiteness tracers and wfk GBS 2020, which in just as few as 3 washes, mimics the whiteness performance observed in wash & wear tests.
• Less labor intensive (less costs, material, time)