Come ridurre i problemi di migrazione del silicone quando si utilizza carta glassine
Creato il 09.08
Reducing silicone migration when using glassine paper is a common challenge in industries like adhesives, plastics, food, and pharmaceuticals. Silicone migration can contaminate products, hinder adhesion, and cause quality defects.
Here is a comprehensive guide on how to reduce and prevent silicone migration issues.
理解问题
- What is Glassine? Glassine是一种超压光、致密且光滑的纸，因其对空气、油脂和水的抵抗力而闻名。其不粘特性源于硅油涂层。
- 什么是硅胶迁移？这是一个过程，其中硅胶涂层的低分子量（LMW）成分从玻璃表面转移到其接触的材料（例如，粘合剂、橡胶、食品、塑料）。
- 为什么这是一个问题？硅胶是一种强大的污染物。它可以：
- Kill Adhesion: Prevent tapes, labels, and adhesives from sticking.
- Cause Fish Eyes: Create imperfections in paints, coatings, and plastic films.
- Contaminate Products: Render food, pharmaceutical, or sensitive electronic components unusable.
- Inhibit Curing: 干扰某些材料（如橡胶或密封剂）的固化过程。
Strategies to Reduce Silicone Migration
The solution involves selecting the right glassine, handling it correctly, and implementing quality control measures.
1. 选择合适的玻璃纸（最关键的一步）
Not all glassine is created equal. The key is to specify glassine designed for low migration.
- Specify "低迁移"或"铂金固化"硅胶：这是最重要的因素。
- 传统过氧化物硫化硅胶：这种较旧的方法可能会留下低分子量硅胶物种和分解副产品，这些物质高度流动且容易迁移。
- 铂催化加成固化：这一更先进的工艺创造了更紧密、更交联的硅氧烷网络。几乎不留下低分子量残留物，极大地减少了迁移的潜在可能性。始终坚持使用铂固化的硅涂层玻璃纸。
- Request a "Cured" Coating: Ensure the silicone coating is fully cured. An under-cured coating will have more free silicone available to migrate. Reputable suppliers will have quality controls to ensure complete curing.
- Consider Coating Weight: Discuss the silicone coating weight (often measured in grams per square meter, gsm) with your supplier. A very thin coating might not provide a consistent barrier, while an excessively thick one could increase migration risk. An optimal, controlled coating weight is key.
- Understand the Base Paper: The density and quality of the underlying paper affect how the silicone is anchored. A high-density, smooth base paper provides a better foundation for the coating.
2. 正确的存储和处理
Environmental factors can accelerate migration.
- 控制温度：将玻璃纸存放在凉爽、气候控制的环境中。高温会增加硅氧烷分子的流动性，使其更容易迁移。避免存放在热源附近、阳光直射下或非空调的仓库中。
- 避免压力和摩擦：
- Do Not Over-stack pallets or rolls. Excessive weight can force the silicone to transfer, especially in warm conditions.
- Minimizar el deslizamiento de las hojas entre sí, ya que la fricción puede desgastar la superficie y liberar partículas de silicona.
- Manage Shelf Life: Use older stock first (FIFO - First-In, First-Out). While high-quality glassine has a long shelf life, properties can degrade over extended periods, especially in poor storage conditions.
3. 过程和应用考虑事项
How you use the glassine also matters.
- Minimizar el tiempo de contacto: Cuanto más tiempo esté un material sensible en contacto con el vidrio, mayor será la posibilidad de migración. Si es posible, reduzca el tiempo de permanencia. Por ejemplo, no almacene productos adhesivos en revestimientos de vidrio más tiempo del necesario.
- 避免“粘连”：粘连是指材料无意中粘附在玻璃纸上，当分离时，它可能会从涂层中拉出硅胶。使用正确的脱模水平（见下文）可以防止这种情况。
- 选择正确的释放级别：玻璃纸有不同的“释放”级别（例如，容易、中等、紧密）。
- Too Easy: 可能表示硅氧烷网络较松，可能增加迁移。
- Correct Level: Provides a clean, consistent release without stressing the coating.
- Too Tight: Can cause fiber tear (pulling paper fibers off) upon release, which is its own contamination problem.
- 与您的供应商合作，测试并选择适合您应用程序的理想发布级别。
4. 质量控制与测试
You can't manage what you don't measure.
- Supplier Qualification: Partner with reputable glassine manufacturers and converters. They should provide certificates of conformity and detailed specifications about their coating process (platinum vs. peroxide).
- Incoming Inspection: Implement simple QC checks for incoming glassine rolls or sheets.
- Migration Testing:
- The "Drawer Test": A common industry practice. Place a sample of the glassine in a closed drawer or container with a sample of your sensitive product (e.g., a piece of adhesive tape or plastic film). Store it at an elevated temperature (e.g., 40-50°C / 104-122°F) for a set period (e.g., 24-72 hours). Afterwards, test the adhesive or material for any loss of tack or performance. This accelerates potential migration.
- Laboratory Testing: For critical applications, labs can use techniques like FTIR (傅里叶变换红外光谱) or GC/MS (气相色谱-质谱联用) to detect and quantify silicone contamination on your product's surface.
Summary: 行动计划
1. 切换到铂金固化玻璃纸：立即联系您的供应商并确认硅胶涂层的类型。切换到铂金固化、低迁移等级。
2. 审核您的存储：确保您的存储区域凉爽、干燥，并避免阳光直射。
3. 审查处理实践：培训员工小心处理卷和纸张，以避免磨损和压力。
4. 实施质量控制测试：首先进行简单的“抽屉测试”以验证新材料批次，并定期检查存储的库存。
5. 与您的供应商沟通：明确您的应用程序和迁移问题。一位优秀的技术销售代表可以帮助您选择完美的等级。
通过采取系统的方法——专注于材料选择、存储、处理和验证——您可以有效消除硅胶迁移作为产品失败的来源。
Ray
Ferrill
Evelyn