UGPCB High-End Epoxy Resin Plugged Rigid-Flex PCB: 16L Rigid + 2L Flex All-in-One Solution

---

As digital electronics evolve toward higher integration, lighter weight, and uncompromised reliability, 剛体PCB have become the critical backbone for complex circuit systems. When space constraints and signal integrity are paramount, combining epoxy resin plugging with rigid-flex technology represents the gold standard for high-density interconnect solutions.

UGPCB leverages advanced manufacturing to deliver an Epoxy Resin Plugged Rigid-Flex PCB built on a FR4 + PI material platform. Featuring a 16L Rigid + 2L Flex 工事, this board is specifically engineered for demanding デジタル製品, offering the mechanical strength of rigid boards alongside the dynamic flexing capability of flexible circuits.

1. 製品の概要 & 意味

An epoxy resin plugged rigid-flex PCB is a hybrid circuit board that integrates rigid PCB sections and flexible PCB sections into a single, unified structure through lamination. This specific product combines 16 rigid layers (FR4) と 2 flexible layers (PI). The rigid section’s vias are filled using a specialized epoxy resin plugging process.

This design retains the bendability of the flex area while eliminating common rigid-flex failure points like “solder blow-out” or trapped air expansion during SMT assembly. The result is a highly reliable 回路基板 optimized for modern, compact digital devices.

2. 材料 & Stack-Up Architecture

The product’s performance relies on precise material selection and structural engineering:

• 基本材料:

  • Rigid Section: FR4 (Glass-reinforced epoxy laminate). This material offers high mechanical strength, excellent thermal stability, および電気絶縁 (meets UL 94 V-0 可燃性評価), providing a stable foundation for component mounting.

  • Flex Section: PI (ポリイミド) 膜. Known for its exceptional heat resistance (operating range: -200°C to +300°C), outstanding dynamic flex life (millions of cycles), 低誘電率, PI is ideal for dynamic flexing applications.

• Stack-Up Configuration:

  • Total Layers: 16L Rigid + 2L Flex (Equivalent to an 18-layer circuit)

  • 銅の厚さ: 1 オズ. As per IPC-4562, 1 OZ copper finished thickness is approximately 35μm. This provides an optimal balance between current-carrying capacity and fine-line etching capability.

  • 仕上がり板厚: 1.0mm. Achieving this thickness in an 18-layer stack demonstrates advanced lamination precision, meeting the industry’s demand for ultra-slim profiles.

  • 表面仕上げ: イマージョンゴールド (同意する). Conforming to IPC-4552, ENIG offers a flat surface, 優れたはんだ付け性, and superior oxidation resistance, making it ideal for fine-pitch component assembly.

3. Epoxy Resin Plugging: 作業原則 & 設計上の考慮事項

3.1 作業原則

In a multilayer rigid-flex PCB, vias electrically connect different layers. In traditional designs, unplugged vias can trap air. During high-temperature processes like lead-free reflow (peak temperatures around 245°C–260°C), this trapped air expands, potentially causing “popcorning,” delamination, or solder ball splatter.

The epoxy resin plugging process uses vacuum printing or injection to fill mechanical drilled holes (minimum size 0.2mm) with a high-viscosity, low-CTE (熱膨張係数) エポキシ樹脂. After filling, the board undergoes thermal curing and surface planarization, making the via surface flush with the board surface.

3.2 設計上の考慮事項

• Aspect Ratio Control: For a 0.2mm minimum finished hole size, アスペクト比 (板厚から穴径まで) must be controlled to ensure void-free filling. With a 1.0mm board thickness, the aspect ratio is 5:1, well within UGPCB’s stringent process capabilities.

• Trace/Space Capability: This product supports 4ミル/4ミル (0.1mm/0.1mm) fine-line circuitry. によると IPC-2221, such precision allows for high-density interconnects. The plugging process is carefully managed to not compromise the insulation distance between these fine traces.

4. 製品分類

Based on IPC-6013, the qualification and performance specification for flexible and rigid-flex boards, this product’s scientific classification is:

• Structural Type: タイプ 4 (リジッドフレックス Multilayer Board)

• Performance Class: クラス 3 (High-Reliability Electronic Products). This class is for products where continued performance is critical, 医療機器など, 産業用制御, and high-end digital consumer goods. It demands a high level of assurance and proven reliability.

5. 製造工程 & 品質管理

UGPCB follows IPC-A-600 standards for manufacturing and acceptance. The core process includes:

1. 内層イメージング: Fine-line circuitry is patterned on both PI and FR4 substrates, with strict control over the 4mil trace/space geometry.

2. Coverlay Lamination: PI coverlay is applied to the flex areas to protect circuits and enhance flex life.

3. Window Cutting & Lay-up: Rigid sections are windowed to expose flex areas, followed by precise alignment and lay-up.

4. ラミネート加工: High temperature and pressure fuse the multilayer stack. This step is critical to avoid wrinkles or separation at the rigid-flex interface.

5. 機械による穴あけ: 0.2mm micro vias are drilled with positional accuracy held within ±0.05mm.

6. Epoxy Resin Plugging: Core Process. Vacuum plugging equipment injects epoxy resin. After curing and sequential grinding, surface planarity meets IPC-4761 Type VII (Filled & Covered) 標準, providing sealed via protection.

7. ENIG Surface Finish: Applied per IPC-4552, ensuring a dense, uniform gold layer free from “black pad” defects.

8. 電気テスト: 100% 飛行探査機 or fixture testing verifies no opens or shorts.

6. 主な仕様 & Reliability Data

All parameters are grounded in industry standards to ensure accuracy and authority:

*Data references: IPC-TM-650 test method manual and UL certification standards.*

7. アプリケーション

Thanks to the high-density routing of the 16L rigid section and the dynamic flex capability of the 2L flex section, this product is primarily targeted at high-end デジタル製品:

• High-End Smartphones & タブレット: Used for camera modules, battery connections, and mainboard interconnects to save internal space.

• デジタルカメラ & Camcorders: Ideal for lens extension modules requiring repeated, high-frequency bending.

• Wearable Electronics: スマートウォッチ, VR/AR headsets. The 1.0mm thin profile and epoxy plugging ensure signal stability in ultra-compact enclosures.

• Solid-State Drives (SSD): Used as the carrier for memory modules, leveraging rigid-flex for multi-layer stacking and interface connections.

8. 製品の特徴 & 利点

1. Integrated Design, Saves Space: Replaces the traditional “PCB + コネクタ + FPC” assembly. This eliminates connectors, reduces BOM costs, and significantly improves signal integrity by minimizing impedance discontinuities.

2. Epoxy Resin Plugging Eliminates Solder Blow-Out: Solves the yield-loss issue caused by outgassing from vias during lead-free reflow soldering.

3. Fine-Line Circuitry: サポート 4ミル/4ミル trace and space, enabling high-density interconnect (HDI) デザイン. The 0.2mm micro vias offer high routing freedom.

4. 高い熱安定性 & Flex Durability: The FR4 and PI combination provides a robust platform for component assembly while ensuring long-term dynamic flex performance.

9. 行動を促す & Inquiry Guidance

UGPCB is more than a circuit board manufacturer. We are your partner in ensuring product reliability.

We understand the manufacturing challenges of epoxy resin plugged rigid-flex PCBs. The key is controlling adhesion at the rigid-flex boundary and guaranteeing void-free plugging. With years of experience, UGPCB utilizes automated vacuum plugging lines, high-precision direct imaging, and rigorous あおい システム. 毎 16L Rigid + 2L Flex board we ship meets クラス 3 reliability standards.

If you need a rigid-flex PCB that can handle high-density routing, lead-free assembly, and dynamic flexing without compromise, UGPCB is your ideal partner.

Contact UGPCB today for a custom quote.

• Submit your Gerber files. Our team will provide a free DFM (製造用のデザイン) analysis within 24 時間.

• 私たちはサポートします prototype そして low-to-medium volume production with flexible lead times.

• Our dedicated engineering team offers one-on-one support to accelerate your digital product launch.