English
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русский1. What Silicone Release Paper Is
Silicone release paper (also called release liner) is a substrate—typically kraft paper, glassine, or coated paper—treated with a silicone release coating on one or both sides. The silicone layer provides a controlled low-adhesion surface so pressure-sensitive adhesives, tapes, labels, and adhesive films can be stored and handled without sticking. Release paper protects adhesive products during processing, die-cutting, lamination, and transport, and is removed easily when the adhesive product is applied.
2. Common Types and Coating Methods
Base Substrates
Typical substrates include unbleached kraft for economy and strength, glassine for superior smoothness and dimensional stability, and clay-coated papers for printability. Choice of substrate affects stiffness, printability, moisture resistance, and cost.
Silicone Coating Types
Silicone release coatings are applied in various chemistries and thicknesses. Common types are solvent-based silicone, solventless (100% solids) silicone, and waterborne silicone emulsions. Each offers different release force ranges, cure requirements, and environmental profiles.
3. Key Specifications to Compare
- Release force (g/25mm or N/25mm): Indicates how easily the adhesive peels from the liner; choose low release for easy unwind and higher release when stability is required.
- Coating weight (g/m²): Thicker silicone layers can provide more consistent release over time and through processing.
- Substrate caliper (µm or gsm): Thicker liners add stiffness and protect heavy adhesives; thinner liners reduce bulk and waste.
- Surface energy and smoothness: Smoother liners allow for precise die-cutting and printing; surface energy impacts coating adhesion.
- Single- or double-sided coating: Double-sided release paper is needed when both sides of a product are adhesive or when laminating double-coated tapes.
4. Typical Applications
- Pressure-sensitive labels and tapes: Release liners protect the adhesive during converting and serve as the backing until application.
- Medical and hygiene products: Liners for wound dressings, transdermal patches, and sanitary adhesives require biocompatible grades and clean converting.
- Electronics assembly: Die-cut release liners support films, protective masks, and adhesive tapes used in display and PCB production.
- Graphic overlays and laminates: Release paper aids roll-to-roll lamination and precise placement of thin films.
5. Practical Buying Checklist
- Match release force to your adhesive and process—ask for peel tests at your operating temperature.
- Specify single or double-sided coating and whether the liner must be printable or printable with specific inks.
- Confirm substrate moisture content and curl behavior for your converting equipment to avoid web breaks.
- Ask about environmental compliance (e.g., solvent emissions, food contact, RoHS) and recyclability or compostability if relevant.
6. Comparison Table — Typical Market Grades
| Grade | Substrate | Coating | Best for |
| Economy | Kraft paper (60–80 gsm) | Solvent-based silicone | General tapes, labels |
| High-performance | Glassine (50–70 gsm) | Solventless or waterborne silicone | Precision die-cut, medical |
| Printable | Clay-coated paper | Modified silicone for printability | Labels requiring inkjet/offset printing |
7. Storage, Handling and Converting Tips
Storage Conditions
Keep rolls in a cool, dry environment away from direct sunlight and humidity. Recommended storage is 18–25°C and 40–60% relative humidity. Avoid stacking heavy loads on top of rolls to prevent edge crushing and set a first-in-first-out (FIFO) system to minimize aging effects.
Converting Practices
Control web tension to reduce curl and wrinkles. Test slit widths and rewind tension for your machine setup. When switching coatings or substrates, run trial laminations and perform adhesion and unwind force tests at production speeds.
8. Troubleshooting Common Issues
Excessive Adhesion / Hard to Peel
Possible causes include an overly aggressive adhesive, low coating weight, or elevated storage temperatures that soften adhesive. Solutions: trial a lower-release silicone grade, increase coating weight, or lower storage temperature.
Tape Pop or Premature Release During Processing
If adhesive releases prematurely while die-cutting or rewinding, check converting tension and unwind balance. Consider a higher release force liner or adjust adhesive formulation to improve tack stability.
9. Frequently Asked Practical Questions
- Can release paper be recycled? Some kraft and glassine liners are recyclable in paper streams if the silicone load and contaminants meet local recycling standards; check with your waste processor.
- Is silicone transfer to adhesive a concern? High-quality silicone chemistries are formulated to minimize migration; ask suppliers for migration test data if silicone contamination affects downstream processes.
- How long can coated liners be stored? Typical shelf life is 6–12 months under recommended conditions; perform periodic peel tests if storage extends beyond this.
10. Final Tips for Specification and Supplier Selection
Provide your supplier with sample adhesive formulations, expected operating temperatures, print or die-cut requirements, and production speeds. Request release force data, samples for pilot trials, and clear environmental compliance documentation. Small upfront trials save time and cost at scale.
