Designation:D4585–07
Standard Practice for
Testing Water Resistance of Coatings Using Controlled Condensation1
This standard is issued under thefixed designation D4585;the number immediately following the designation indicates the year of original adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.A superscript epsilon(e)indicates an editorial change since the last revision or reapproval.
1.Scope*
1.1This practice covers basic principles and operating procedures for testing water resistance of coatings using controlled condensation.Condensation is produced by expos-ing one surface of a coated specimen to a heated,saturated mixture of air and water vapor,while the reverse side of the specimen is exposed to the cooling effect of room temperature air.This practice is derived from research of the Cleveland Society for Coatings Technology.2
1.2This practice is limited to the methods of obtaining, measuring,and controlling conditions and procedures of con-trolled condensation tests.It does not specify specimen prepa-ration,specific test conditions,or evaluation of results.
N OTE1—Alternative practices for testing water resistance of coatings include Practices D870,D1735,and D2247.
1.3The values stated in SI units are to be regarded as the standard.The values given in parentheses are for information only.
1.4This 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 and health practices and determine the applica-bility of regulatory limitations prior to use.
2.Referenced Documents
2.1ASTM Standards:3
D609Practice for Preparation of Cold-Rolled Steel Panels for Testing Paint,Varnish,Conversion Coatings,and Related Coating Products
D610Test Method for Evaluating Degree of Rusting on Painted Steel Surfaces
D714Test Method for Evaluating Degree of Blistering of Paints
D823Practices for Producing Films of Uniform Thickness of Paint,Varnish,and Related Products on Test Panels
D870Practice for Testing Water Resistance of Coatings Using Water Immersion
editor evaluating revisionD1654Test Method for Evaluation of Painted or Coated Specimens Subjected to Corrosive Environments
D1730Practices for Preparation of Aluminum and Aluminum-Alloy Surfaces for Painting
D1735Practice for Testing Water Resistance of Coatings Using Water Fog Apparatus
D2247Practice for Testing Water Resistance of Coatings in 100%Relative Humidity
D2616Test Method for Evaluation of Visual Color Differ-ence With a Gray Scale
D3359Test Methods for Measuring Adhesion by Tape Test D3363Test Method for Film Hardness by Pencil Test
D4541Test Method for Pull-Off Strength of Coatings Using Portable Adhesion Testers
G154Practice for Operating Fluorescent Light Apparatus for UV Exposure of Nonmetallic Materials
3.Summary of Practice
3.1Water vapor is generated by heating a pan of water at the bottom of the test chamber.The specimens form the roof or walls of the test chamber so that the back sides of the specimens are exposed to the cooling effects of room tempera-ture air.The resulting heat transfer causes vapor to condense on the test specimens as liquid water saturated with air.
3.2The temperature and amount of condensate forming on the specimens is controlled by the test temperature and the room temperature.The test specimens are inclined so that condensate runs off the test surface by gravity and is replaced by fresh condensate in a continuous process during the condensate cycle.
3.3Exposure conditions are varied by selecting:(a)the temperature of the test,(b)the duration of the test,and(c) periodic drying of the specimens.Testing may be conducted at temperatures from38to82°C(100to180°F).Any effects such
1This practice is under the jurisdiction of ASTM Committee D01on Paint and
Related Coatings,Materials,and Applications and is the direct responsibility of
Subcommittee D01.27on Accelerated Testing.
Current edition approved June1,2007.Published July2007.Originally approved
in1986.Last previous edition approved in1999as D4585–99.
2Foecking,N.J.,“Cleveland Condensing Type Humidity Cabinet,”Offıcial
Digest,December1963,V ol35,No.467,pp.1318–1327;and Higgins,W.A.,
“Cleveland Condensing Type Humidity Cabinet:II,”Offıcial Digest,November
1965,V ol37,No.490,pp.1392–1404.
3For referenced ASTM standards,visit the ASTM website,,or
contact ASTM Customer Service at For Annual Book of ASTM
Standards volume information,refer to the standard’s Document Summary page on
the ASTM website.
*A Summary of Changes section appears at the end of this standard. Copyright©ASTM International,100Barr Harbor Drive,PO Box C700,West Conshohocken,PA19428-2959,United States.
as color change,blistering,loss of adhesion,softening,or embrittlement are observed and reported.
4.Significance and Use
4.1
Water can cause degradation of coatings,so knowledge of how a coating resists water is helpful in predicting its service life.Failure in a condensation test may be caused by a number of factors including a deficiency in the coating itself,contami-nation of the substrate,or inadequate surface preparation.The test is therefore useful for evaluating coatings alone or com-plete coating systems.
4.2Condensation tests of coatings are used for specification acceptance,quality control,and research and development of coatings and substrate treatments.These tests usually result in a pass or fail determination but the degree of failure also may be measured.A coating system is considered to pass if there is no evidence of water-related failure after a specified period of time.
4.3Results obtained from the use of condensation tests in accordance with this practice should not be represented as being equivalent to a period of exposure to water in the natural
environment,until the degree of quantitative correlation has been established for the coating or coating system.
4.4The test is usually conducted on metal,plastics,or wood specimens with the coating facing the inside of the chamber. However,it is possible to test the blister resistance of house paints on wood specimens by mounting the uncoated wood surface facing the inside of the chamber.
4.5This practice can be used for corrosion tests particularly if the specimens are periodically dried.While corrosion prod-ucts will drain into the water bath,they are not carried into the vapor that condenses on the test specimens.
5.Apparatus
5.1Test Chamber(see Fig.1and Fig.2),consisting of insulated side walls mounted on a base,test specimen racks attached to the side walls,a heated water pan,and provisions for controlling and indicating the vapor temperature within the chamber.Vents,approximately3to5mm(0.10to0.20in.) wide,shall be provided to admit room air at the bottom of the test chamber.Locate the chamber away from air vents and direct drafts.
N OTE2—The apparatus described in Practice G154may be used if the ultraviolet lamps specified in Practice G154are turned off.
5.2Specimens shall form the roof of the test chamber.If the specimens cannot completelyfill all the openings,blank panels shall be used.Certain substrates may deform from the heat and moisture.The specimens should be mounted to avoid gaps between specimens that allow heat and moisture to escape. Various types of tape can be used to seal the gaps that develop when the specimen deforms.Specimens shall be inclined from 15to75°from the horizontal and arranged so that condensate is returned to the water pan without dripping on other speci-mens.
5.3Water Supply,with water level control.The water quality should be agreed upon between the customer and the supplier for running this test.
5.4Water Heater,preferably located under the water pan, controlled by a thermostat with the sensing element located in the water.
5.5Thermometer,with the stem extending into the air-water vapor mixture in the test chamber.
5.6Program Timer,Blower,and Air Heater,(optional)fitted to the chamber to provide periods of drying on afixed schedule.
6.Test Specimens
6.1This practice does not cover the preparation of test specimens.The substrate composition and surface preparation, specimen preparation,and the number of specimens should be agreed upon prior to testing.
N OTE3—Applicable methods for the preparation of test panels and substrates are given in Practice D609and Practices D1730.Practices D823cover application techniques for the production of uniformfilms.
6.2It’s recommended that a control specimen of a paint with known durability be included with each test.Such control specimens can provide warning of changes in test severity in a given apparatus,and can indicate variations in test severity between different apparatuses.
6.3It’s recommended that at least two replicate specimens of each different coating be used,so as to compensate for variations between specimens and variations in test conditions within the apparatus.
FIG.1Controlled Condensation Apparatus
FIG.2Apparatus Cross Section
6.4Test specimens should beflat rigid material.Minimum size is76-mm(3-in.)wide and152-mm(6-in.)tall.
Maximum thickness is8mm(3⁄4in.).Materials thicker than8mm(3⁄4in.) insulate and the condensate does not form on the tested side of the panel.If the test panels overshadow the upper shelf,do not put test panels on the upper shelf.Check the samples periodi-cally to make sure condensation is occurring.
N OTE4—A3mm glass plate in place of a sample will work to monitor whether condensation is occurring.
7.Procedure
7.1Fill the water pan to a depth of approximately25mm(1 in.)with water.The quality of the water in the pan does not affect the test since the evaporation and condensation process yields distilled water,but the use of tap water can result in the accumulation of residues in the water pan.
7.2Fill all spaces in the specimen holder rack with speci-mens or corrosion-resistant blank panels.Mount coated metal panels with the coating to be tested facing the inside of the chamber.Coated wood specimens may be mounted in the same way.
7.2.1Blister tests to simulate the effects of water vapor migration from inside a frame house are mounted with the uncoated side of the wood specimen facing the inside of the test chamber.
7.2.2Close all cracks between specimens and all holes in specimens,to prevent water vapor loss and local temperature variation.Condensate usually seals cracks or holes smaller than1mm(0.04in.),but larger openings must be closed with tape or metal strips.
7.3Adjust the thermostat to maintain the desired tempera-ture of the saturated air and water vapor mixture.Vapor temperatures of38,49,or60°C(100,120,or140°F)are suggested.Other temperatures may be used provided that the temperature is reported in conformance with Section8.To ensure adequate condensation,maintain at least a11°C(20°F) temperature differential between the room and the vapor.
7.4Operate the chamber continuously unless otherwise specified or agreed.The removal of specimens for inspections during operation is permitted.When removing a specimen for inspection,replace it with a blank so that the test conditions are not altered.
7.5Cyclic operation with alternating periods of condensa-tion and drying may be used.Automatic drying requires the apparatus described in5.6.For manual drying of specimens, remove them from the apparatus.Drying periods should be at least4h long.
7.6To control for variability within the apparatus,reposi-tion the specimens on a regular basis so that all specimens spend equivalent amounts of time in the various areas of the apparatus(top,bottom,left,right,
and center).
7.7Conclude the test after a specified period of time or after effects from exposure to water are noted.
7.8Remove specimens at the conclusion of the test.Do not leave the specimens in the apparatus at the conclusion of the test as the specimens can remain wet for hours,or even days, when the apparatus is turned off.
7.9Wipe the test specimens dry.Rate specimens for changes in color,blistering,etc.Evaluate specimens no less than5min and no more than10min after removal from test, as the effects from water exposure can change within a short time.Remove only as many specimens as can be rated within the specified time.
N OTE5—Relevant procedures for evaluating water effects are de-scribed in Test Methods D610and D2616,and Test Methods D714, D1654,D3359,D3363,and D4541.
7.9.1If possible,rate the specimens again after they have been removed from the test for a recovery period long enough that moisture absorbed within the specimen dries out and the specimens reach moisture equilibrium with room air.A recov-ery period from12to24h is generally sufficient.The post-reco
very rating allows evaluation of the permanent effects of the exposure as distinct from the transient effects,and is especially important for evaluation of color and gloss.
8.Report
8.1Report the following information:
8.1.1Sample identification.
8.1.2Results of the evaluation(s).
8.1.3Reference to Practice D4585.
8.1.4Hours of test duration.
8.1.5Description of any cyclic operations.
8.1.6Condensation temperature.
8.1.7Special conditions of test or any deviations in test procedure.
9.Keywords
9.1adhesion;blistering;condensation;humidity;resistance-water;
rust
SUMMARY OF CHANGES
Committee D01has identified the location of selected changes to this standard since the last issue (D4585-99)that may impact the use of this standard.(Approved June1,2007.)
(1)The references to Practice G53have been changed to Practice G154.Practice G53has been replaced by Practice G154.
(2)A sentence was added to5.1about the location of the apparatus.(3)A sentence was added to6.4to check the samples regularly for condensation.
(4)A Note4was added to allow the use of a3mm piece of glass to check for condensation.
(5)Note4was renumbered to Note5.
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