1、Designation:F2213Standard Test Method forHydrophobic Surface Films by the Water-Break Test1This standard is issued under the fixed designation F22;the number immediately following the designation indicates the year of originaladoption or,in the case of revision,the year of last revision.Anumber in p
2、arentheses indicates the year of last reapproval.Asuperscriptepsilon()indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S.Department of Defense.1.Scope1.1 This test method covers the detection of the presence ofhydrophobi
3、c(nonwetting)films on surfaces and the presenceof hydrophobic organic materials in processing environments.When properly conducted,the test will enable detection ofmolecular layers of hydrophobic organic contaminants.Onvery rough or porous surfaces,the sensitivity of the test may besignificantly dec
4、reased.1.2 The values stated in SI units are to be regarded as thestandard.The inch-pound values given in parentheses are forinformation only.1.3 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to
5、 establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2C813 Test Method for Hydrophobic Contamination on Glassby Contact Angle MeasurementD351 Classification for Natural Muscovite Block Mic
6、a andThins Based on Visual QualityD1193 Specification for Reagent WaterD2578 Test Method for Wetting Tension of Polyethylene andPolypropylene FilmsD5946 Test Method for Corona-Treated Polymer Films Us-ing Water Contact Angle MeasurementsD7334 Practice for Surface Wettability of Coatings,Sub-strates
7、and Pigments by Advancing Contact Angle Mea-surementD7490 Test Method for Measurement of the Surface Tensionof Solid Coatings,Substrates and Pigments using ContactAngle MeasurementsF21 Test Method for Hydrophobic Surface Films by theAtomizer Test3.Terminology3.1 Definitions:3.1.1 contact angle,nthe
8、interior angle that a drop makesbetween the substrate and a tangent drawn at the intersectionbetween the drop and the substrate as shown in Fig.1;this isthe angle formed by a liquid at the three phase boundary wherea liquid,gas(air)and solid intersect.3.1.2 hydrophilichaving a strong affinity for wa
9、ter,wet-table.3.1.2.1 DiscussionHydrophilic surfaces exhibit zero con-tact angle with water.A sessile drop of water applied to thesurface will immediately spread out to form a film.3.1.3 hydrophobichaving little affinity for water,nonwet-table.3.1.3.1 DiscussionHydrophobic surfaces exhibit contactan
10、gles between a sessile drop of water and the surfaceappreciably greater than zero.3.1.4 sessile dropa drop of liquid sitting on the upper sideof a horizontal surface.3.1.5 water-breaka break in the continuity of a film ofwater on a surface on removal from an aqueous bath or onremoval of a flowing wa
11、ter source from the surface.4.Summary of Test Method4.1 The water-break test is performed by withdrawing thesurface to be tested,in a vertical position,from a container ofpurified water and observing the behavior of the water.Forlarge parts,the test surface may be doused with water and thewater beha
12、vior observed on removal of the water source.4.2 The interpretation of the test is based upon the pattern ofwetting.Contaminated areas having a surface tension lowerthan water will cause the water to bead up at that location or“break”while draining.Most common film contaminants suchas oils,silicones
13、,or fluorocarbon greases have surface tensionssignificantly lower than water.In the absence of hydrophobicfilms,the draining water layer will remain as a film over the1This test method is under the jurisdiction of ASTM Committee E21 on SpaceSimulation and Applications of Space Technology and is the
14、direct responsibility ofSubcommittee E21.05 on Contamination.Current edition approved Nov.1,2013.Published November 2013.Originallyapproved in 1962.Last previous edition approved in 2007 as F22 02(2007).DOI:10.1520/F0022-13.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact
15、 ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 surface.In areas where hydrophob
16、ic materials are present onthe surface,the draining water layer will break up into adiscontinuous film within one minute.NOTE1It is possible to use this test method with liquids other thanwater.Liquids with different wetting tensions will exhibit different contactangles with a given surface and therefore different levels of sensitivity tohydrophobic films.This principle has been applied to develop differentialwetting tension tests such as described in Test Method D2578 usingstandardized liquids
