Technologies FAQ

What is RFL?

In the chemical industry, RFL stands for Resorcinol Formaldehyde Latex. It is a widely used set of chemical formulations that are applied for bonding fabric with rubber. The RFL dipped fabric and rubber form a chemical bond during the rubber curing process. The result is a reinforced rubber part that will not delaminate even under high stress.

What fabric is used for diaphragms?

The fabrics that reinforce rubber diaphragms are usually specially designed for mouldability, flexibility and elongation under stress. To avoid delamination between the fabric and rubber, the fabric is dipped for adhesion to the rubber compound. Compotex offers a range of diaphragm fabrics from 100 – 400gsm which includes the treatment for rubber adhesion.

What is the shelf life of RFL?

Compotex always recommends that their RFL dipped fabrics are kept wrapped in black polythene until used. This is because RFL will react with light and the adhesion will slowly degrade. If kept wrapped, we recommend that the fabric is normally used within 12 months. Where high adhesion with the rubber compound is critical, we suggest that the fabric is used as soon as possible to avoid any unnecessary variation.

How do you bond to EPDM rubber?

In the past, only solvent treatments have given a bond to EPDM rubber. But now Compotex has developed water based systems for fabric adhesion for both sulphur and peroxide curing EPDM.

How can you improve the adhesion of fabric with silicone rubber?

Companies usually try to coat silicone directly on to fabric. But for dynamic and high performance parts the rubber must not delaminate off the fabric. In these cases a dipped fabric must be used. During the curing process the silicone rubber bonds into the fabric. Solvent treatment is a possibility but Compotex water based treatments with a long shelf life and stability are recommended.