Some Like It Soft - Wacker Chemie AG

Some Like It Soft

Synergies with Silicones

In spite of this compelling mechanism, until just a few years ago, acceptance of silicones in the price-sensitive fabric-softener market was muted. However, this is starting to change. Rising raw-material prices are making silicone softening agents ever more attractive. “Esterquats and silicones harmonize particularly well with each other, they complement and even enhance each other’s properties – this makes for attractive synergy effects,” says WACKER chemist Dr. Becker. As a result, mixtures of esterquats and novel functionalized silicones are now being used in fabric softeners more and more frequently (see Figure 1).

  • Softness Test

    In a series of comparative studies, employees tested terry towels that had been washed with and without silicone.

  • Wetting Test

    Water is dripped onto the fabric and then the time taken for the drop to soak in is measured.

  • Ironing Test

    On a sloped surface, chemists test to what extent silicones can simplify the ironing of fabrics.

  • Burghausen Lab

    An employee measuring the contact angle in an analytical lab in Burghausen.

Enhanced Wetting of Fibers

WACKER® FC 218 is a milky, opaque, aqueous macroemulsion of an amino-functional polydimethylsiloxane. Fabric softeners formulated with WACKER® FC 218 render the treated fabrics soft and wrinkle resistant and make them easier to iron. Hydrophilicity, the wetting property of the fibers, is also improved, making the product effective in applications where moisture has to be absorbed quickly by the fabric, as is the case in towels.

To determine how WACKER® FC 218 silicone fluid emulsions influence the properties of a fabric softener, Dr. Becker had the softness, water uptake and ease of ironing of freshly treated fabrics tested at the applications laboratory in Burghausen. A fabric softener formulated with ten percent esterquat and no silicone was compared to a formulation with a reduced 6.5 percent esterquat content and 1.29 percent silicone added.


The chemists in Burghausen examined the ability to absorb water of the two formulations – with and without WACKER® FC 218 – using the TEGEWA drop test. This is a standardized test method of the German TEGEWA – an industrial association whose members include manufacturers of textile auxiliaries and detergent raw materials.

Drip and Measure

To determine the wetting property, a droplet (70 microliters) of deionized water is carefully dripped onto the fabric and then the time taken for the drop to fully soak in is measured. The laboratory staff carry out this measurement three times on each of several, usually five, different places on the fabric and then calculate a mean value. Its outcome showed that the water-uptake speed increased significantly when the fabric softener was formulated with silicone: textile fibers were wetted after an average of about 16 seconds; with no silicone added, wetting took approximately 90 seconds. (Figure 1).