Znaczenie i cel

5.1 Wraz ze wzrostem oporu pędzla farby, any natural tendency of the painter to overapply the paint will decrease. When all other factors are held constant, increasing brush resistance will result in greater film thickness, resulting in improved durability and concealment. Przeciwnie, it may sometimes be preferred to use a lesser degree of brush drag for easier application (tj., using a lesser degree of brush drag reduces the time and effort required to apply paint to a particular area).

5.2 This test method provides a standardized spawning procedure for assessing brush resistance as an alternative to the customary informal temporary procedure. The goal is to increase the reliability and precision of determining this feature as much as possible.

Notatka 1: Brush drag of paint is directly related to its high shear viscosity. There is generally good ranking order agreement between the results obtained by this method and the test method D4287. The sensitivity of this brushout method has been found to be sufficient to distinguish brush rates corresponding to high shear viscosity differences of not less than 0.3 poise (0.03 Pa.s). The cyclic data show that the ranking order agreement between the brush and viscosity methods is poor when latex and solve-based coatings belong to the same comparison group. This is due to the fact that the two paint types have significantly different rheological properties that can affect the relative perception of brush resistance. four

ASTM D4958-2016 “Porównanie możliwości nakładania pędzla farbą lateksową”

Zakres

1.1 This test method is a standardized brushing procedure for comparing brush resistance of architectural solvent-based coatings.

1.2 With slight modifications, this test method is also applicable to solvent-based coatings.

1.3 Wartości wyrażone w jednostkach SI należy traktować jako wzorce. Wartości podane w nawiasach służą wyłącznie celom informacyjnym.

1.4 Celem tej normy nie jest omówienie wszystkich kwestii związanych z bezpieczeństwem, Jeśli w ogóle, związane z jego użytkowaniem. Obowiązkiem użytkowników niniejszej normy jest ustanowienie odpowiednich praktyk w zakresie bezpieczeństwa i higieny pracy oraz określenie możliwości zastosowania ograniczeń regulacyjnych przed użyciem.