Knowledge Base
Standards
ASTM D3258 is a global ASTM international standard method to determine the porosity of white or near white mineral spirits in insoluble paint films. This ASTM test method achieves this by staining to indicate the degree to which a subsequent coat will penetrate.
To undertake the ASTM D3258 test you’ll need film applicators, a reflectometer, a vacuum drawdown plate, a camel hair brush, a plastic wash bottle, a test panel, a penetrating medium and filter paper.
Following this ASTM method, the test paint is applied to a nonporous surface, air dried, then measured for reflectance. A special colored penetrating medium is applied, the excess is removed in a specified manner, and reflectance measured again. The difference between the two readings indicates the degree of porosity; the smaller the difference, the lower the porosity of the film and the greater its ability to resist penetration.
So, how can Industrial Physics improve your ASTM D3258 testing?
Single gap, bird-type film applicators
The TQC Sheen bird-type film applicator has one flat edge and is designed to support testing to standards including ASTM D3258. It’s a great choice for coating laboratories and companies involved in paint production.
The ‘bird-type’ applicator single gap is available in two different sizes and is suitable for applying a range of coatings onto flat and relatively solid substrates. It’s a robust device and the high-grade stainless steel is unaffected by acid or base elements.
Click here to find out more.
Your global test and measurement partner for ASTM D3258
TQC Sheen’s range of custom-sized Baker applicators are designed to be used for film application and drawdown to meet your specific testing needs.
TQC Sheen’s range of custom-sized Bird applicators are available as one-sided or four-sided, designed to be used for film application and drawdown.
TQC Sheen’s wide range of Bird applicators are available as one-sided or four-sided , designed to be used for film application and drawdowns. For custom-sized applicators, click here for options.
TQC Sheen’s wide range of Baker applicators designed to be used for film application and drawdowns. For custom-sized applicators, click here for options.
TQC Bird-type film applicator 50mm, 200µm Sheen Instruments equivalent product code: SH1100/50
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