DOWSIL PR1204
Harmonization Code : 3208.20.90 | Paints and varnishes that are dispersed or dissolved in a non aqueous medium
Main features
- Adhesion-Promoting Surface Treatment
- Light, Even Application by Wiping, Dipping
- Room-Temperature Adhesive Cure
Product Description
DOWSIL™ PR-1204 RTV Prime Coat is a clear liquid adhesion promoter used before moisture-cure RTV or heat-cure silicone application. Applied as a very light, even film, it improves silicone bonding to many metals, glass, ceramics and masonry. The product can be wiped, dipped or sprayed, with typical non-volatile content of 7.9% and 180-degree peel strength of 66 ppi (45.5 N/cm²) on aluminum. After application, the carrier solvent evaporates and the active ingredients cure with atmospheric moisture, typically for 1 to 2 hours at room temperature and 20 to 90% relative humidity. Surface cleanliness, thin-film control and complete primer cure are important to bonding performance.
Key features
- Multi-substrate adhesion promotion: Supports RTV and heat-cure silicone bonding to many metals, glass, ceramics and masonry.
- Flexible application methods: Applies by wiping, dipping or spraying as a very light, even coat.
- Room-temperature moisture cure: Typically cures for 1 to 2 hours at 20 to 90% relative humidity.
- Aluminum peel result: Typical 180-degree peel strength is 66 ppi (45.5 N/cm²) on aluminum.
- Defined storage life: Typical shelf life is 18 months at 25°C when stored and handled as directed.
Suitable for
- Moisture-cure RTV silicone bonding processes.
- Heat-cure silicone bonding processes.
- PCB system assemblies requiring evaluation of primer-assisted silicone adhesion.
TDS, SDS & Technical Documents
Technical Specifications
No specifications available.
Additional Information
DOWSIL™ PR-1204 RTV Prime Coat
DOWSIL™ PR-1204 RTV Prime Coat is a clear adhesion-promoting surface treatment for moisture-cure RTV and heat-cure silicone systems. Applied as a very thin film, it supports bonding to many metals, glass, ceramics and masonry. Typical data include 7.9% non-volatile content and 180-degree peel strength of 66 ppi (45.5 N/cm²) on aluminum; these values are not specifications.
DOWSIL PR-1204 RTV Prime Coat.
Typical as-supplied properties
Values are typical and should not be used as product specifications.
| Property | Value | Unit | Method / condition |
|---|---|---|---|
| Physical state | Liquid | - | As supplied |
| Color | Colorless to pale yellow | - | As supplied |
| Non-volatile content | 7.9 | % | Typical value |
| Kinematic viscosity | 1 | mm²/s | At 25°C |
| Relative density | 0.77 | - | Water = 1 |
Application process
Bonding performance depends on surface preparation, complete wetting, very light primer application and full primer cure before the silicone elastomer is applied.
Store below 32°C (90°F), keep containers tightly closed, minimize headspace and prevent moisture ingress. Partially filled containers may be purged with dry air or nitrogen. Pour only small amounts for immediate use into clean, dry containers and discard remaining material after use. Do not use material that becomes milky or contains a large amount of white precipitate. Typical shelf life is 18 months at 25°C. The product is highly flammable; keep it away from heat, sparks, flames and other ignition sources, and use appropriate ventilation and protective measures in accordance with the current regional SDS.
Application control guidance
| Issue or observation | Technical guidance | Qualification boundary |
|---|---|---|
| White or chalky surface after application | This generally indicates overapplication. Wipe off excess material and reduce the applied coat. For dip or spray processes, 2- to 4-fold dilution with additional solvent may help limit build-up. | Confirm the selected dilution and application process by testing with the actual substrate and silicone system. |
| Cure is slower than expected | Low temperature or humidity extends cure time. Allow additional time. Mild heat may accelerate cure, but temperatures above 60°C (140°F) are not recommended. | Determine the appropriate cure schedule for the actual temperature, humidity, substrate and assembly conditions. |
| Milky appearance or substantial white precipitate | These conditions indicate moisture contamination. Do not use the affected material. | A small amount of white precipitate limited to the container-cap area does not affect the bulk material. |
| Poor wetting or inconsistent adhesion | Review surface cleanliness and reactivity. Mild abrasion, solvent cleaning and, for difficult surfaces, chemical or energy-based pretreatment may improve surface preparation. | Select and validate the preparation method for the exact substrate, finish, contamination state and silicone system. |
Applications
The primer is relevant where a thin adhesion-promoting treatment is required before applying compatible RTV or heat-cure silicone to a prepared surface. Validate the complete substrate, primer, silicone and cure combination for the intended assembly.
Evaluate DOWSIL PR-1204 for your silicone bonding process
Krayden can help review substrate preparation, application method, primer film control, cure conditions and silicone compatibility for your assembly. Share your substrate, process and performance requirements to plan product evaluation and confirm an appropriate handling and test approach.
