Introduction

Aluminum Coated Transfer Paper (ACTP) is a specialized substrate material engineered for high-performance thermal transfer applications. This composite material consists of a base paper layer coated with a precisely controlled aluminum layer, typically ranging from 0.5 to 5 microns in thickness, combined with a heat-activated adhesive system. The aluminum coating provides exceptional thermal conductivity (≈237 W/m·K), while the paper substrate offers flexibility and dimensional stability with a typical tensile strength of 30-50 N/cm in the machine direction.

Key Characteristics and Technical Specifications

Thermal Performance

The aluminum coating achieves a thermal reflectivity of 85-95% across the infrared spectrum (2.5-25 μm wavelength), with an emissivity value of 0.03-0.1. This enables efficient heat transfer with minimal energy loss, making ACTP particularly effective for applications requiring precise thermal management. The material maintains structural integrity within a temperature range of -40°C to 220°C, with a maximum peak temperature tolerance of 250°C for short durations.

Mechanical Properties

ACTP demonstrates excellent mechanical characteristics, including a Young's modulus of 3-5 GPa and a tear resistance of 400-600 mN (Elmendorf method). The base paper typically has a grammage of 60-120 g/m², with surface smoothness measuring 100-300 Bekk seconds. These properties ensure reliable performance during high-speed transfer processes while preventing wrinkling or deformation.

Surface Characteristics

The aluminum coating achieves a surface roughness (Ra) of 0.1-0.5 μm, optimized for uniform heat distribution. The material exhibits a contact angle of 70-90°, indicating moderate hydrophobicity that prevents moisture absorption (≤2% at 50% RH). Optical properties include a gloss level of 60-80 GU at 60° and a whiteness index of 85-95% (CIE standard).

Applications

Industrial Thermal Transfer

In industrial settings, ACTP serves as a critical component in:

• Textile Printing: Enables high-resolution (up to 1440 dpi) transfer of designs onto synthetic fabrics at temperatures of 180-210°C with dwell times of 15-30 seconds.

• Packaging: Used for metallic finish applications on flexible packaging materials, achieving a transfer efficiency of ≥95% at line speeds up to 150 m/min.

• Automotive Interiors: Transfers decorative aluminum finishes to polyurethane components with a bond strength of ≥3 N/mm (DIN 53530).

Electronics Manufacturing

The material finds specialized applications in electronics production:

• PCB Manufacturing: Serves as a thermal interface material for transferring conductive patterns, with a dielectric strength of ≥15 kV/mm.

• Flexible Circuits: Enables transfer of metallic traces with a line width resolution of 25-50 μm and resistivity of 2.8-3.2 μΩ·cm.

Decorative Applications

ACTP facilitates high-end decorative finishes in:

• Architectural Elements: Transfers mirror-finish aluminum coatings to MDF and acrylic substrates with a reflectivity of ≥85%.

• Consumer Products: Creates metallic finishes on plastic housings with a scratch resistance of ≥2H (pencil hardness test).

Maintenance and Handling

Storage Conditions

Proper storage is essential for maintaining ACTP performance:

• Maintain ambient temperature of 15-25°C and relative humidity of 40-60% RH

• Store rolls vertically on edge to prevent deformation (maximum stack height: 5 rolls)

• Use original packaging with moisture barrier (WVTR ≤1 g/m²/day)

• Rotate stock using FIFO (First In, First Out) system with maximum storage duration of 12 months

Handling Procedures

Follow these guidelines for optimal material handling:

• Wear clean, powder-free gloves when handling (recommended nitrile gloves with ≥5 mil thickness)

• Maintain cleanroom conditions of Class 1000 or better for critical applications

• Use tension control systems set to 1-2 N/cm during unwinding

• Avoid sharp bending (minimum bend radius: 50 mm)

Cleaning and Maintenance

For equipment using ACTP:

• Clean rollers weekly with isopropyl alcohol (≥99% purity)

• Inspect and replace guide rollers showing wear beyond 0.05 mm TIR

• Maintain nip pressure within 20-40 N/cm for consistent transfer

• Calibrate temperature sensors monthly with accuracy of ±1°C

Troubleshooting

Common issues and solutions:

• Incomplete Transfer: Increase temperature by 5-10°C increments up to maximum rating

• Coating Adhesion Failure: Verify substrate surface energy (≥38 dynes/cm)

• Wrinkling: Adjust tension to 1.5±0.2 N/cm and check roller alignment (≤0.1 mm/m)

• Oxidation Spots: Maintain storage humidity below 60% RH and use within 6 months