Silicone mold processing is a precision manufacturing technique that transforms liquid silicone rubber (LSR) or condensed silicone rubber into elastic, detail-rich molds. By infusing uncured silicone onto prototype surfaces, it replicates complex structures—from 0.05mm micro-textures to large architectural components. Its core strengths (бюджетный, short cycle, high customization) make it a go-to for rapid sampling, Маленькая партийная производство, and personalized crafts. But how does the process work, what materials are best, and how to avoid common pitfalls?
1. Key Materials for Silicone Mold Processing: Match to Use Cases
The performance of a silicone mold depends entirely on material selection. Below is a breakdown of silicone types, their characteristics, and ideal applications—aligned with core material traits from industry standards:
| Силиконовый тип | Ключевые характеристики | Стандарты соответствия | Типичные приложения |
| Medical-Grade Silicone | Withstands high-temperature steam sterilization (121° C+); биосовместимый (no skin irritation) | FDA 21 CFR §177.2600; Iso 10993 | Medical orthosis production (НАПРИМЕР., custom braces), food-contact molds (chocolate, candy) |
| Industrial-Grade Silicone | Adjustable hardness (Shore A 5–60°); balances tear strength (>3кн/м) and resilience | ГБ/т 5574 (industrial rubber standards) | Resin handicraft molding, architectural decoration component duplication, industrial part prototyping |
| Specialty Conductive Silicone | Contains conductive fillers (НАПРИМЕР., carbon black); maintains flexibility | МЭК 60093 (электрическая проводимость) | Electronic device packaging (НАПРИМЕР., sensor gaskets, anti-static mold inserts) |
| Condensed Silicone Rubber | Бюджетный; cures via moisture absorption (releases ethanol); easy to mix | Industrial-grade only (no food/medical use) | Low-criticality crafts (НАПРИМЕР., simple plaster molds), temporary seals |
2. Step-by-Step Workflow of Silicone Mold Processing
Silicone mold processing follows a standardized 4-stage cycle—each step critical to capturing details and ensuring mold durability. The process is linear, with clear quality checkpoints:
Этап 1: Prototype Pre-Treatment (Заложить фундамент)
- Уборка: Wipe the prototype (3D print, physical object, or master model) with isopropyl alcohol to remove oil, пыль, or fingerprints. Even tiny debris causes mold defects (НАПРИМЕР., оспины).
- Исправление: Secure the prototype to a flat base (НАПРИМЕР., acrylic plate) using double-sided tape. Ensure it’s centered—this prevents uneven silicone distribution.
- Release Agent Application: Распылять тонкий слой PVA water-soluble release agent or silicone-specific release spray. This reduces adhesion, making demolding easier (critical for fragile prototypes like resin models).
Этап 2: Silicone Blending (Mix for Uniformity)
- Component Ratio: Mix silicone main agent and curing agent in a precise ratio (common ratios: 10:1 for industrial-grade, 1:1 for LSR). Use an electronic scale (±0.1g accuracy) to avoid curing failures.
- Добавки (При необходимости):
- For color-coded molds: Add non-toxic pigments (1–2% of total weight) to the main agent before mixing with curing agent.
- For heat-resistant molds: Incorporate thermal powder (НАПРИМЕР., глинозем) to boost temperature tolerance (до 200 ° C.).
- Defoaming: Медленно перемешать смесь (30–50 RPM) for 2–3 minutes, then place in a vacuum chamber (-0.1МПА) for 15–20 minutes. This removes air bubbles—without it, the mold will have holes that ruin details.
Этап 3: Gate Molding (Capture Details)
- Containment Setup: Build a frame (wood or acrylic) around the prototype. The frame should be 5–10cm taller than the prototype’s highest point to prevent silicone overflow.
- Техника заливки: Slowly pour the blended silicone over the prototype’s edges (not directly on top) at a rate of 1–2cm/min. This lets silicone flow into micro-details (НАПРИМЕР., 0.05mm texture lines) without trapping air.
- Leveling: Tap the frame gently 2–3 times to release surface bubbles. For deep cavities, use a small brush to guide silicone into gaps—avoiding air pockets.
Этап 4: Выклятый & Демольд (Finalize the Mold)
- Curing Conditions:
- Отверждение при комнатной температуре: Let stand for 24–48 hours (ideal for condensed silicone; humidity 40–60% works best).
- Ускоренное отверждение: Heat in an oven at 60–80°C for 2–4 hours (speeds up LSR curing; reduces cycle time for small-batch production).
- Демольд: После вылечения (test by touching the silicone—should be firm, not sticky), peel the mold from the prototype’s edges. Use a plastic spatula to lift stuck areas—never pull hard (this stretches the mold).
- Post-Trim: Cut off excess silicone (вспышка) with sharp scissors. Sand the mold’s inner edges with 400-grit sandpaper for a smooth finish (improves the quality of cast parts).
3. Сравнение: Silicone Molds vs. Traditional Molds
Silicone molds outperform traditional options (сталь, эпоксидная смола) in key areas—especially for small-scale or custom projects. The table below highlights the differences:
| Особенность | Silicone Molds | Стальные формы | Epoxy Resin Molds |
| Equipment Investment | Низкий (no large machines needed; works with basic tools) | Высокий (requires CNC machining centers; $50k+ setup) | Середина (needs mold frames and mixing equipment) |
| Detail Replication | Отличный (captures 0.05mm microstructures; ideal for textures) | Хороший (limited to 0.1mm details; best for smooth parts) | Справедливый (prone to bubble traps; loses detail in deep cavities) |
| Служба срока службы | Умеренный (30–50 cycles for industrial-grade; 10–20 for craft-grade) | Длинный (100k+ cycles; Для массового производства) | Короткий (5–10 cycles; brittle and prone to cracking) |
| Совместимость материала | Широкий (supports polyurethane, gypsum, цемент, смола, and low-temperature metals) | Ограничен (best for plastic injection molding) | Узкий (only works with low-viscosity resins) |
| Время цикла | Быстрый (24–48 hours per mold) | Медленный (2–4 weeks for machining) | Середина (3–5 days for curing) |
4. Общие проблемы & Solutions in Silicone Mold Processing
Even experienced operators face issues—most stem from poor process control. Below is a cause-and-effect guide to troubleshooting:
| Испытание | Первопричина | Practical Solution |
| Mold Dimensional Deviations | Ambient temperature/humidity fluctuations; uneven curing shrinkage | – Cure in a temperature-controlled room (20–25 ° C., 40–60% влажность).- Используйте силикон с низким кручением (<0.5% скорость усадки; НАПРИМЕР., LSR).- Add a 1–2% dimensional allowance to the prototype. |
| Пузыри в форме | Fast pouring; inadequate vacuum defoaming; stirring too vigorously | – Pour silicone at 1cm/min; avoid splashing.- Extend vacuum time to 25 минуты; repeat if bubbles remain.- Stir at 30 Rpm (use a slow-speed mixer if available). |
| Сложный демонтаж | Insufficient release agent; prototype surface roughness | – Apply a second thin layer of release agent (focus on textured areas).- Sand rough prototype surfaces with 600-grit sandpaper before pre-treatment. |
| Mold Tearing During Use | Low tear strength silicone; thin mold walls (<5мм) | – Switch to industrial-grade silicone with tear strength >4kN/m.- Make mold walls 8–10mm thick for high-cycle use (НАПРИМЕР., 50+ casts). |
5. Best Practices for Silicone Mold Maintenance
Proper care extends a silicone mold’s service life from 10 cycles to 50+. Follow these tips:
- Clean Immediately Post-Use: Wipe the mold with warm water and neutral detergent (НАПРИМЕР., мыло для посуды) after each casting. Avoid harsh chemicals (acetone dissolves silicone).
- Высохнуть тщательно: Pat the mold with a lint-free cloth, then air-dry in a cool, shaded area. Moisture trapped in cavities causes mold growth.
- Store Correctly:
- Lay flat (never fold) to prevent permanent creases.
- Для долгосрочного хранения (1+ месяц), dust the mold’s inner surface with talcum powder to prevent sticking.
- Repair Minor Damage: Fix small tears with a drop of silicone main agent + лечительный агент (10:1 соотношение). Лечение от 24 hours before reuse.
6. Yigu Technology’s Perspective on Silicone Mold Processing
В Yigu Technology, we see silicone mold processing as a catalyst for rapid innovation—especially for small businesses and creators. For architectural firms, our industrial-grade silicone (Shore A 20–30°) has replicated 1:10 scale building facades with 0.05mm texture accuracy, cutting prototyping time by 60% против. epoxy molds. For medical device makers, our medical-grade LSR molds meet FDA standards, enabling custom orthosis production with 24-hour turnaround.
We’re optimizing two key areas: 1) Developing eco-friendly condensed silicone (reducing VOCs by 30%) for sustainable crafting; 2) Integrating 3D scanning to automate prototype pre-treatment (обеспечение 100% silicone coverage). Our goal is to make high-precision silicone mold processing accessible—no large equipment required.
Часто задаваемые вопросы
- Can I reuse a silicone mold made via this process, and how many times?
Yes—reusability depends on the silicone type: Industrial-grade molds last 30–50 cycles; медицинский состав (LSR) molds last 50+ цикл; craft-grade condensed silicone lasts 10–20 cycles. Proper cleaning (теплая вода + detergent) and storage (плоский, сухой) extend life.
- What’s the best way to avoid curing shrinkage in silicone molds?
Используйте силикон с низким кручением (НАПРИМЕР., LSR with <0.5% усадка) and control curing conditions: Cure at 20–25°C (avoid extreme temperatures) and 40–60% humidity. For large molds, add a 1–2% dimensional allowance to the prototype (НАПРИМЕР., a 10cm prototype becomes 10.1cm to offset shrinkage).
- Can silicone mold processing be used for high-temperature casting materials (НАПРИМЕР., low-melting metals)?
Yes—but choose the right silicone: Use industrial-grade silicone with thermal powder additives (heat resistance up to 200°C) for low-melting metals (НАПРИМЕР., pewter, melting point 170°C). Avoid medical-grade or condensed silicone—they deform above 120°C. Always test a small mold sample first to confirm heat tolerance.