Laboratory Preparator

A wet film applicator is a laboratory tool used to apply a predetermined thickness of wet paint film onto a flat substrate, providing the foundation for subsequent dry film performance testing.

This article explores the alignment accuracy control when using a four-sided preparator in conjunction with an automatic coating machine. Alignment accuracy directly affects the uniformity of the coating and the reliability of detection.

The film applicator is a crucial tool in fields such as coatings and inks for preparing test samples, ensuring uniform thickness and a smooth surface through standardized operations. The article introduces its scraping-based working principle and the selection between manual and automatic types.

This article compares two commonly used tools in laboratory coating film preparation: the wire rod coater and the wet film applicator.

When using a wet film applicator, maintaining a constant speed during the scraping process is crucial for coating uniformity. The scraping speed directly affects the wet film thickness, and fluctuations in speed can lead to defects such as streaks and uneven thickness, compromising the repeatability and accuracy of experimental results.

The wire-wound drawdown bar directly quantifies the coating through the gap between wires, making it suitable for thin coating preparation with high precision, particularly for low-viscosity fluids. In contrast, the gap-type wet film applicator indirectly controls film thickness through the groove depth, with the actual coating thickness significantly influenced by material properties, making it more suitable for high-viscosity coatings and thick film preparation.