LLW Pressure Measurement Film (2LW): Pressure Range, Applications, and Reading Guide

LLW pressure measurement film, also referred to as 2LW, is designed for ultra-low pressure applications where accurate detection of moderate contact forces is required. Understanding its pressure range, application scenarios, and reading method is essential for obtaining reliable pressure distribution results.

What Is LLW (2LW) Pressure Measurement Film?

LLW is a double-layer pressure-sensitive film consisting of an L-sheet and a K-sheet. When pressure is applied, the microcapsules in the film react to produce a visible color pattern that reflects pressure distribution.

Key specifications:

• Pressure range: 0.5 MPa – 2.5 MPa
• Film size: 270 mm × 6 m
• Structure: Double-layer (L-sheet + K-sheet)

This model is positioned between micro-pressure films and standard low-pressure films, making it suitable for controlled and uniform pressure environments.

Typical Applications of LLW Film

LLW pressure measurement film is commonly used in applications where pressure is relatively low but still requires clear visualization and comparison.

Typical use cases include:

• Assembly contact verification
• Lamination pressure inspection
• Sealing surface uniformity testing
• Electronic component compression checks

In these applications, LLW film helps identify uneven pressure distribution, insufficient contact, or localized pressure variations.

How Pressure Distribution Is Displayed

After pressure is applied, the film develops a color pattern that directly represents the pressure distribution.

• Darker red areas indicate higher pressure
• Lighter red areas indicate lower pressure
• Uniform color suggests consistent load distribution

For accurate observation, the developed K-sheet should be placed on a white background with the PET surface facing upward and viewed under sufficient lighting conditions.

How to Determine Pressure Values

For quantitative analysis, the developed film can be compared with a standard pressure–density curve.

Key steps:

• Match the color density of the film with the reference color chart
• Select the appropriate curve based on test conditions
• Consider factors such as temperature, humidity, and pressure duration

Different pressing conditions (such as sustained or instantaneous pressure) may require different reference curves for accurate interpretation.

Selection Guidelines for LLW Film

When deciding whether LLW (2LW) is suitable, consider the following:

• Use LLW when the expected pressure falls within 0.5 MPa to 2.5 MPa
• Avoid using it for extremely low-pressure applications (below range)
• Avoid exceeding the upper limit, which may cause over-saturation

Choosing the correct pressure range ensures better color resolution and more reliable measurement results.

Conclusion

LLW pressure measurement film (2LW) is designed for ultra-low pressure applications requiring clear and stable pressure distribution analysis. By understanding its pressure range, application scenarios, and reading method, users can achieve accurate and repeatable results in practical testing environments.