Why do small holes appear in the paint? Three overlooked causes that lead to pinhole defects.
The small hole that appears as a pinhole is a paint defect caused by the overlap of oil, moisture, and material condition.
■Cause of Occurrence: Pinholes are defects where small holes remain on the surface of the paint film. During visual inspection, even one instance is subject to selection. There are three main causes: oil residue on the surface of the material, moisture due to insufficient drying, and voids or unevenness in the material. These factors allow air or gas to escape during painting, creating holes. ■Truth: The areas with holes have interrupted paint films, leading to weaknesses in corrosion resistance and adhesion. In aluminum die casting and castings, internal cavities or gas escape in the material are also relevant. Simply repainting the surface will not prevent recurrence unless the pre-treatment and material condition are verified. ■Improvement Measures: By recording the three points of degreasing to remove oil, ensuring no moisture remains during drying, and checking for voids or roughness, you can narrow down the causes by cross-referencing with defective lots. Since pinholes can also lead to blistering and rust recurrence, please utilize materials that can help organize pre-treatment, drying, and material conditions.
basic information
Corresponding materials: Iron, aluminum die-cast, zinc die-cast, castings / Confirmation of 3 processes: Degreasing, drying, surface condition of the material / Film thickness: 20-40 microns / Identification and response to causes of pinholes, blisters, and rust recurrence / Support for small lots and short delivery times.
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Applications/Examples of results
Automotive parts, aluminum die casting, cast parts, products for appearance inspection.
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