Why can geckos walk on walls or even upside down on ceilings?
To find the riddle‘s solution the animals have to be observed in their natural environment and examined by state-of-the-art technology, such as the scanning electron microscope.
Flies for example secrete an adhesive on “the soles of their feet“ that enables them to even “stick“ on wind-screens at a speed of 30 km/h. Geckos, which as tropical small reptiles are much bigger and heavier, adhere to smooth walls without any secretion. The assumption that geckos cling is wrong.
Geckos are little masters as far as adhesion is concerned; they seem to even easily annul defined gravitational laws. Why are they able to do that?
The answer: Tiny nanohair on their feet help geckos to build up mechanical grip on extremely smooth surfaces and to defy gravity. Nature often uses this technique of adhesive power; insects too make use of it. Geckos, however, are the champions in their class!
Lamellae geckos even run headlong on glass panes thanks to the perfect adhesion of billions of fine hair (spatulae; ca. 200 nanometer wide and long) on their footpads, thus making use of the Van der Waals forces.
Amongst all animal species which have been examined so far, geckos have the highest number of spatulae per unit area. However, compared to flies or other insects, they are relatively heavy animals.
The geckos‘ trick is a fascinating solution of nature that is worth having a closer look at and considering it in technical applications.
RUDOLF GROUPS‘s textile coating division has orientated itself according to nature for quite some time. Thus, we have succeeded in developing a new adhesive system for textile surfaces that imitates the properties of geckos. To improve adhesion to smooth surfaces is an important challenge to many textiles.
As described above, the well-known GECKO-FINISH RUDOLF® creates a special adhesive power on smooth materials, such as glass, metal or varnished surfaces, that will exceed its own weight of finished fabric samples by far.
Whilst the “conventional“ GECKO-FINISH RUDOLF® could so far only be created by transfer coatings, the new GECKO-FINISH RUDOLF® can now be produced with the common direct coating operations, such as air knife or knife over roller, either as foam or as paste!
In both cases, an incredible adhesive power of textiles on substrates is the result. The adhesive power related to the respective substrate can even be tuned to a finer extent, which extends the choice of bondable substrates to even coarse walls - without leaving residues on the substrates when removed. Multiple usage is guaranteed!
The new GECKO-FINISH RUDOLF® opens up new fields of application, such as textile wall tattoos, exhibition designs, protective textiles, adhesive tapes, sun protection, acoustic insulation, decorations on virtually all substrates, permanently or temporarily! The use is even possible in public areas, since the DIN 4102B1 standard can be complied when adding a suitable flame retardant (®RUCO-COAT FR 2200 or 2250) to suitable fabric.