The screening detergency test is run with standard soiled cloths in a miniature laboratory washing machine following the guidelines of ASTM D 3050. The test is useful for formulating work and for comparing products in preparation for more extensive washing machine and in home testing. Usually one or more commercial or standard laundry detergents are run at the same time to provide a frame of reference since soils and fabrics change constantly.
Scientific Services standard Dust Sebum and Ground in Clay soiled swatches are used. Clean swatches of three different fabrics are included to measure redeposition. The U.S. Testing Co., Inc. Terg-o-Tometer is used for the laundering and rinsing steps. Reflectance's of the swatches are read before and after laundering on the "L" scale of a reflectometer. Results are reported as average change in "L" value for the six soil-fabric combinations and for the three fabrics. Results for the two soils and redeposition are summed to give scores which are totaled for a grand total score. These total scores aid in interpretation of the comparative results.
Scientific Services standard Dust Sebum and Ground in Clay soiled swatches are used. Clean swatches of three different fabrics are included to measure redeposition. The U.S. Testing Co., Inc. Terg-o-Tometer is used for the laundering and rinsing steps. Reflectance's of the swatches are read before and after laundering on the "L" scale of a reflectometer. Results are reported as average change in "L" value for the six soil-fabric combinations and for the three fabrics. Results for the two soils and redeposition are summed to give scores which are totaled for a grand total score. These total scores aid in interpretation of the comparative results.
STANDARD LAUNDRY CONDITIONS
|
Temperature-
Water Hardness- Detergent Concentration- Terg-o-Tometer Speed- Dissolve Time- Wash Time- Rinse Time- Soiled Cloth Load- |
90ºF
150 ppm Ca/Mg 2/1 Recommended Use Level 100 cpm 2 Minutes 10 Minutes 5 Minutes 2 Swatches each: Dust Sebum Soiled Cotton #400 Dust Sebum Soiled Cot. PEDP 7435 WRL Dust Sebum Soiled Polyester #777 2 Swatches each: Ground in Clay Soiled Cotton #400 Ground in Clay Soiled Cot. PEDP 7435 WRL Ground in Clay Soiled Polyester #777 1 Swatch each: Clean Cotton #400 Clean Cot. PEDP 7435 WRL Clean Polyester #777 |
Many variations from the standard conditions can be made to your specifications. Runs are made in sets of four at one temperature, but detergent concentration, temperature and water hardness are often varied. Replication is recommended unless the ranges of variables permit interpolation to spot aberrant results.
Soil redeposition, stain removal, calcium carbonate (CaCO3) deposition and dye fading/transfer are examples of other tests of laundry products and additives studied in the Terg-o-Tometer. Contact George C. Feighner for additional information.
Soil redeposition, stain removal, calcium carbonate (CaCO3) deposition and dye fading/transfer are examples of other tests of laundry products and additives studied in the Terg-o-Tometer. Contact George C. Feighner for additional information.