ASTM D3450-15(R2020) pdf free download

ASTM D3450-15(R2020) pdf free download.Standard Test Method for Washability Properties of Interior Architectural Coatings
1. Scope
1.1 This test method covers the determination ofthe relative ease of removing soilant discolorations from the dried film of an interior coating by washing with either an abrasive or nonabrasive cleaner. 1.2 This test method is limited to coatings having a CIE-Y reflectance of 60 % or more, as measured in accordance with Test Method E1347. 1.3 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only. 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appro- priate safety, health, and environmental practices and deter- mine the applicability ofregulatory limitations prior to use. 1.5 This international standard was developed in accor- dance with internationally recognized principles on standard- ization established in the Decision on Principles for the Development of International Standards, Guides and Recom- mendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
3. Terminology
3.1 Definitions ofTerms Specific to This Standard: 3.1.1 soilant, n—a discoloring substance that clings to the surface ofa coating, whose dispersed color component is not in solution and therefore does not penetrate into the film. 3.1.1.1 Discussion—Soilant differs from stain in that the colorant of a stain is in solution and, therefore, can penetrate into the film.
4. Summary of Test Method
4.1 The test material is applied to a black plastic panel and allowed to dry for 7 days. The reflectance of the film is measured (R 1 ) and then a soilant consisting of carbon black dispersed in mineral oil is applied on the film. The panel is placed on a glass plate in a washability machine and the film is washed with either an abrasive or nonabrasive scrub medium for 100 cycles. The panel is rinsed and dried and the reflectance in the stained area is read (R 2 ). The ratio of the reflectance, R 2 /R 1 , is a measure of the degree to which the soilant has been removed.
5. Significance and Use
5.1 Interior architectural paints are often discolored by dirt and other soilant materials. This test method covers the relative ease and completeness of removal of a specific soilant from such a surface by scrubbing. The greater the ease of soil removal with a minimum of film erosion, the greater the useful service life is expected to be. 5.2 Results obtained by this test method do not necessarily correlate with all types of soilants. 5.3 Semigloss finishes generally require only the nonabra- sive type cleaner for good soilant removal, whereas flat paints may require the abrasive type.
9. Procedure
9.1 Clean the top ofthe glass plate (or preferably the suction plate) and both sides of the black plastic panel to be sure they are free of specks. Place the black panel on the plate and tape one end to the plate. Smooth the panel along the plate to ensure a close fit. 9.2 Stir the test material thoroughly and strain to remove all skins and particles. Draw down the material on the panel, starting from the taped end of the panel. For latex paints, the 0.25-mm (10-mil) side of the applicator will generally be satisfactory, whereas the 0.18-mm (7-mil) side can be used for solvent-based coatings. However, the film thickness of paint to be applied may be varied as mutually agreed upon between the purchaser and the seller. The rate ofapplication should be fairly slow, 3 to 4 s from end to end, to prevent pinholes or holidays in the film. Air dry in a horizontal position for 7 days in a room preferably maintained at 23 6 2°C (73.5 6 3.5°F) and 50 6 5 % relative humidity, or under conditions mutually agreeable to the purchaser and the seller. 9.3 On the last day of drying, measure the directional reflectance (green filter) ofa portion ofthe panel in accordance with Test Method E1347. Record this value as R 1 . 9.4 After reading the reflectance, use the applicator with the 3-mil (75-µm) clearance to draw down a film of soilant medium perpendicular to the coating film and in the area where the reflectance was measured. Permit the stained panel to dry for 16 to 24 h under the same drying conditions specified in 9.2. 9.5 Clean the glass surface on which the test panel is to be mounted and also the back of the test panel. Attach the test panel to the glass plate and place the mounted test panel, coated side up, in the pan. Clamp the assembly securely to the pan with the “C” clamps, centering the pan so that the sponge boat can move lengthwise on the panel.