Atex® silicone coated membranes can be joined or seamed with silicone adhesive tape available from the Silmix Division of Wacker Chemical Corporation. The following procedure and parameters are intended as a guide for seaming Atex® with the silicone adhesive tape
Attach tape: Apply the tape carefully to the edge of the first sheet of Atex® fabric, lightly rolling as the tape in unrolled to maintain its position.
Roll down tape: Apply moderate pressure with a 3kg hand roller on the side with the separation film. Roll over three times to remove all air bubbles and to fix the tape onto the substrate.
Remove backing film: Carefully peel back and remove the separation film as shown in graphic.
Add second layer: Apply the next sheet of Atex® fabric material onto the exposed upper adhesive side of the tape, carefully aligning the edges.
Roll together: Apply moderate pressure with the hand roller by rolling over the seam three times, paying attention that all air bubbles are removed between the upper surface of the tape and the second sheet of Atex® material.
Apply heat & pressure:Cure the tape by applying heat and pressure to the seam with a heated press, heat sealer, or similar equipment. Heat, as well as pressure is essential to achieving optimum bonding performance. Typical curing parameters are given in the table on the right.
The data presented here is in accordance with the present state of our and / or our suppliers knowledge, but do not absolve the user from carefully checking all parameters for the particular usage. We reserve the right to alter product constants within the scope of technical progress or new developments. The recommendations made here should be checked by preliminary trials because of conditions during processing over which we have no control, especially where other companies’ raw materials are also being used. The recommendations do not absolve the user from the obligation of investigating the possibility of infringement of third parties’ rights and, if necessary, clarifying the position. Recommendations for use do not constitute a warranty, either expressed or implied, of the fitness or suitability of the products for a particular purpose.
Typical Processing Parameters
|Pressure||15 N / cm2||20 lb / in2|
|Time (duration)||30-60 sec|
Stated conditions for curing are basic recommendations, curing conditions for manufacturing are always specific to a process and subject to trials. These figures are only intended as a guide and should not be used in preparing specifications.
When joining or seaming Atex® architectural fabrics with silicone adhesive tape it is recommended that the following practices are employed for best performance.
- Avoid rapid changes in fabric temperature as this might lead to condensation build-up and impact adhesion (e.g. by trying to bond sections of fabric that have been stored well below ambient conditions without allowing them to reach room temperature prior to bonding).
- Do not clean the fabric with ionic detergents, residues of the detergents might impact adhesion. Do not use soap, dishwashing detergents or similar cleaners. Instead use isopropyl alcohol or similar alcohol-based cleaners.
- Do not use a “rubber” roller to remove air bubbles and to fix the tape to the substrate (use a PVC or metal roller). Some rubber compounds contain chemicals that can affect the curing mechanism of the silicone and have a negative impact on adhesion.