The starting point
Start with what touches the surface and how the part is used. Both silicone-coated and PTFE-coated fabrics are candidates for release applications. The finished construction, movement, cleaning exposure and operating conditions determine which grade to trial. Neither material name is a complete specification.
01 / Material comparison
Compare equivalent constructions
A solid silicone rubber sheet, silicone-coated fiberglass mat and PTFE-coated fiberglass liner are different assemblies. Separate the working coating from its support. The coating affects contact behavior; reinforcement and geometry affect fit, handling and loading.
Compare products that could perform the same job. Record coating, substrate, thickness, surface finish, open or closed construction, edges and any adhesive. Comparing polymer names alone can hide the feature that determines performance.
02 / Material comparison
What to compare for your process
| Requirement | Silicone candidate | PTFE candidate |
|---|---|---|
| Release and handling | Trial the actual silicone finish with the contact product. | Trial the PTFE finish for release and required sliding movement. |
| Support | Identify solid rubber or fiberglass reinforcement; do not assume equal stretch. | Confirm fabric reinforcement, bend radius and edge construction. |
| Airflow | Choose a continuous surface or open mesh. | Choose closed coated cloth or open mesh. |
| Heat exposure | Request limits for the finished grade and exposure cycle. | Request limits for coating, substrate, adhesive and joints together. |
| Cleaning | Confirm liquids, concentration, temperature and contact time. | Confirm compatibility of the whole part, including edges and adhesive. |
| Food-contact use | Match documents to the supplied grade and contact conditions. | Match documents to the supplied grade and contact conditions. |
03 / Material comparison
Build a shortlist around the job
- Bakery trays: compare release, base texture, tray fit and handling using the actual recipe and cycle.
- Food drying: decide whether the surface must retain a wet product or allow air through it before comparing coatings.
- Heat sealing: record contact temperature, cycle time, pressure, sliding motion and adhesive requirements.
- Custom liners: include holes, edge finish, support spacing and repeated bending, where relevant.
04 / Material comparison
Run a controlled sample comparison
Use the same equipment settings, contact product, loading and cleaning method for each candidate. Record the starting condition and agree the acceptance criteria before the trial.
- Check fit and handling before loading.
- Record release, sticking, unwanted marking and dimensional change after processing.
- Inspect edges, coating and joints after cleaning and repeated use.
- Keep the sample identifier with each observation so the selected construction can be quoted again.
05 / Material comparison
Two common selection mistakes
Which material has the higher temperature limit? Request grade-specific limits under comparable conditions. A peak rating cannot replace a continuous limit, and an adhesive or printed layer can change the assembly limit.
Can I keep the same thickness when changing materials? Treat thickness as one field, not a measure of equivalent performance. Recheck fit, flexibility, reinforcement, surface behavior and loading.
Sources & scope
The selection steps are SIFMAT buyer guidance. External references explain material principles and examples; they do not establish the performance or compliance of a SIFMAT grade.
- Shin-Etsu — Characteristic Properties of Silicone Rubber Compounds
General silicone formulation and exposure behavior; not a SIFMAT finished-product specification.
- Ammeraal Beltech — PTFE Product Range
Manufacturer examples of coated-fabric constructions and applications; not SIFMAT product ratings.
Your next step
Compare Materials for Your Process
Tell us the contact product, temperature profile, equipment, dimensions, cleaning method and quantity. Include the current material if you are replacing a liner.
Compare Materials for Your Process