1、Designation: E2355 10Standard Test Method forMeasuring the Visible Light Transmission Uniformity of anAbsorptive Electrochromic Coating on a Glazing Surface1This standard is issued under the fixed designation E2355; the number immediately following the designation indicates the year oforiginal adopt
2、ion or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 The test described is a method for measuring theuniformity of an absorpti
3、ve electrochromic coating (ECC) in astatic colored or bleached state on a glazing surface, which isor will be one of two or more glazings in a preassembledpermanently sealed insulating glass unit (IGU).1.2 The test method is applicable only for layered (one ormore active coatings between the TCOs) a
4、bsorptive ECCs onvision glass (superstrate and substrate) areas planned for use inbuildings, such as glass doors, windows, skylights, and exteriorwall systems. The layers used for electrochromically changingthe optical properties may be inorganic or organic materialsbetween the superstrate and subst
5、rate and may include lami-nates.1.3 The test method is not applicable to other types ofcoatings on vision glass with other chromogenic coatings thatcannot be held in a static colored or bleached state.1.4 The test method is not applicable to IGUs that will beconstructed from superstrate or substrate
6、 materials other thanglass.1.5 The test method is not applicable for measuring theuniformity of ECC coatings during the coloring or bleachingprocesses.1.6 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.7 There is no comparabl
7、e International Standards Organi-zation Standard.1.8 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 establish appro-priate safety and health practices and determine the applica-bility of re
8、gulatory requirements prior to use.2. Referenced Documents2.1 ASTM Standards:2C168 Terminology Relating to Thermal InsulationC1048 Specification for Heat-Treated Flat GlassKind HS,Kind FT Coated and Uncoated GlassE2141 Test Methods for Assessing the Durability of Ab-sorptive Electrochromic Coatings
9、on Sealed InsulatingGlass UnitsE2188 Test Method for Insulating Glass Unit PerformanceE2189 Test Method for Testing Resistance to Fogging inInsulating Glass UnitsE2190 Specification for Insulating Glass Unit Performanceand EvaluationE2240 Test Method for Assessing the Current-Voltage Cy-cling Stabil
10、ity at 90C (194F) of Absorptive Electrochro-mic Coatings on Sealed Insulating Glass UnitsE2241 Test Method for Assessing the Current-Voltage Cy-cling Stability at Room Temperature of Absorptive Elec-trochromic Coatings on Sealed Insulating Glass Units3. Terminology3.1 DefinitionsRefer to Terminology
11、 C168 for definitionsof general terms.3.2 Definitions of Terms Specific to This Standard:3.2.1 bleached statea descriptor for an EC coating whenno ions reside in the electrochromic layer or after ions havebeen removed (or inserted, depending on the type of material)from the electrochromic layer(s) a
12、nd if applicable, the maxi-mum number of ions have been returned to the counterelec-trode layer to restore the photopic optical specular transmit-tance in the bleached state (tb) from that of the photopic opticalspecular transmittance in the colored state (tc).3.2.2 colored statea descriptor for an
13、EC coating afterions have been inserted (or removed, depending on the type ofmaterial) into the electrochromic layer and, if applicable,1This test method is under the jurisdiction of ASTM Committee E06 onPerformance of Buildings and is the direct responsibility of Subcommittee E06.22on Durability Pe
14、rformance of Building Constructions.Current edition approved Oct. 1, 2010. Published November 2010. Originallyapproved in 2004. Last previous edition approved in 2004 as E235504. DOI:10.1520/E2355-10.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Servic
15、e at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.removed from the counterelectrode layer to red
16、uce the photo-pic optical specular transmittance (of wavelengths from 400nm to 730 nm) from that in the bleached state (tb).3.2.3 durabilitythe capability of maintaining the service-ability of a product, component, assembly, or construction overa specified time.3.2.4 electrochromic coating (ECC)the
17、multilayered ma-terials that include the electrochromic layers, other layers, andtransparent conducting oxide layers required for altering theoptical properties of the coating.3.2.5 electrochromic layer(s)the material(s) in an ECglazing that alter its optical properties in response to theinsertion o
18、r removal of ions, for example, Li+or H+.3.2.6 electrochromic (EC) glazinga device with an ECCconsisting of several layers of electrochromic and attendantmaterials and one or more lites of glass, which are able to altertheir optical properties in response to a change in an appliedelectric field. The
19、 changeable optical properties include trans-mittance, reflectance, and absorptance result in changes in thesolar heat gain, visible transmittance, and U-factor of the glass.3.2.7 fenestrationany opening in a buildings envelopeincluding windows, doors, and skylights.3.2.8 performance parametersthe p
20、hotopic transmittanceratio (PTR) between the bleached and colored states; coloringand bleaching times; and open-circuit memory.3.2.9 photopic transmission ratio (PRT)the ratio of thephotopic transmission in the highest transmission, bleachedstate (tb) to the photopic transmission in the lowest trans
21、mis-sion (colored) state, (tc). PTR= tb/ tc.3.2.10 sealed insulating glass unitis defined in Specifica-tion E2190 but see also Appendix X1, Section X1.3.3.2.11 serviceabilitythe capability of a building product,component, assembly, or construction to perform the func-tion(s) for which it was designe
22、d and constructed.3.2.12 uniformitythe variation in visible light transmis-sion within an EC glazing.3.3 For additional useful definitions for terminology used inthis standard, see Appendix X1, Section X1.3.4. Significance and Use4.1 The ECCs used in the test method will ultimately beexposed (Test M
23、ethod E2141) to solar radiation and deployedto control the amount of radiation by absorption and reflectionand thus, limit the solar heat gain and amount of solar radiationthat is transmitted into the building.4.2 The test method referenced herein is a laboratory testconducted under specified condit
24、ions. This test method isintended for use in assessing the changes in uniformity of anECC on vision glass and subjected to a series of tests forassessing the durability of the coating or the IGU unit, or both.4.3 The useful life of IGUs with an absorptive ECC maydepend on their ability to maintain a
25、n acceptable uniformitywhen used in an IGU for buildings applications. As describedin Section 1.3(See Appendix X1, X1.4 and X1.5), this testmethod is intended to provide a means for measuring theuniformity of an absorptive electrochromic coating (ECC) on aglazing surface (including when sealed in an
26、 insulating glassunit).4.4 Effects of Test ProceduresData generated using thistest method may be used to evaluate and compare the effects ofsubjecting ECCs in IGUs to the accelerated weathering proce-dures described in Test Methods E2141, E2240,orE2241. Thistest method requires the measurement of un
27、iformity as a basisfor evaluating changes in one of several performance param-eters.4.4.1 Changes in the uniformity of the test specimens mayvary from none to significant. Some physical changes in thespecimens may be visible when there are no apparent changesin the performance. Similarly, performanc
28、e changes may occurwith no visible changes in the specimens.4.4.2 All conditions of measurement in this test methodmust be described in the report so that an assessment of theirsignificance can be made.4.5 SequencingIf this test method is performed as part ofa combined sequence with other measuremen
29、ts of the ECCperfomance (see 8.2) and visual inspection (see 8.3 in TestMethods E2141, E2240,orE2241) determined at the end ofone of the test methods, the result may be used as the initialuniformity measurement for the next test; duplication of theseuniformity measurements is not necessary unless so
30、 specified.5. Background5.1 Durability is a critical requirement for and EC glazingproduct for use on the building envelope. In selecting thematerials, device design, and glazing for any application, theability of the glazing to perform over time is an indication ofthat glazings durability. The purp
31、ose of this standard testmethod is to measure the uniformity of an absorptive electro-chromic coating (ECC) on a glazing surface.5.2 EC IGUs perform a number of important functions in abuilding envelope including: minimizing the solar energy heatgain; providing for passive solar energy gain; control
32、ling avariable visual connection with the outside world; enhancinghuman comfort (heat gain), security, ventilation, illumination,and glare control; providing for architectural expression; and(possibly) improving acoustical performance. Some of thesefunctions may deteriorate in performance over time.
33、 Largechanges in the uniformity of an ECC on a glazing surface mayresult in an unacceptable visual connection with the outsideworld, illumination, glare control, or in the architecturalexpression by the fenestration product.3Czanderna, A. W., Benson, D. K., Jorgensen, G. J., Zhang, J-G., Tracy, C. E
34、.,and Deb, S. K., “Durability Issues and Service Lifetime Prediction of Electrochro-micWindows for BuildingsApplications,” NREL/TP-510-22702, National Renew-able Energy Laboratory, Golden, CO, May 1997; Solar Energy Materials and SolarCells, 56, 1999, pp. 419-436.E2355 1026. Apparatus6.1 Laboratory
35、Space, that is large enough for the largestECC-glass specimen to be measured and that will maintain theECC testing temperature at 22 6 3C (72 6 5F). The spacemust permit using the equipment needed for making theuniformity measurements.6.2 Positioning Mechanism, that will hold and position thelight s
36、ource-detector pair(s) above and under the ECC sample.Because the sample sizes can vary, the light source-detectorpair(s) shall be moveable and adjustable.6.3 Holding Mechanism, that will hold a coated glassspecimen in the central position between the light source anddetector and that maintains the
37、correct beam size diameter(within the allowed tolerance). The repeatability of positioningis to be 63 mm. Clamp the source and detector pair to the glassduring measurement to avoid stray light.6.4 Computer Controlled Photodiode Array Spectrophotom-eter, for obtaining and storing data from the electr
38、o-opticalcharacterization of the optical transmittance in the colored andbleached state. The resolution of the transmittance (T) mea-surement shall be 0.1 %T.6.4.1 Broadband Lamp, that will provide a broadbandspectrum from the light source and that must be compatiblewith illuminating the photodiode
39、array spectrophotometerdescribed in 6.4 and that will provide sufficient intensity from400 to 720 nm. The illumination spot size of the source on thesample shall be 50 6 3 mm in diameter. Choose a source of“cool” light to minimize localized heating that could adverselyimpact the uniformity of the EC
40、C. The stability of the lamp formaking the transmittance measurements shall be sufficient toprovide the needed accuracy and precision.NOTE 1A 5-cm diameter spot size provides good reproducibility ofthe measurement of any broad non-uniformities in the ECC and allowsprecision measurements to be made w
41、ithout placing tight tolerances on theposition of the spot. The measurement may also be made with a smallerspot size, for example, 2-cm that is sequentially positioned until the areaof a 5-cm diameter circle has been sampled.6.4.2 Transmittance Measurements, to a precision of60.5 % T and with an acc
42、uracy of 62 % of the measuredtransmittance or 60.5 % in transmittance, whichever is thegreater.NOTE 2The accuracy is 60.5 % in the measured transmittance up toT = 25 % and then 2 % of the transmittance value for all T 25 %. Thus,the two criteria prevent specifying an unrealistic measurement accuracy
43、 atsmall values of T, such as in the colored state.6.5 Transmission Standards, to calibrate the equipmentappropriately.To calibrate the transmittance (T) measurements,select transmission standards that span the entire dynamicrange to be measured. For example, if an ECC sample with adynamic transmitt
44、ance range of 55 to 4 % is to be measured,calibration standards in the range of T = 3 to 5 % and in therange of T = 50 to 60 % are required.6.6 Temperature Measurement EquipmentUse an instru-ment or instruments to measure the temperature of the speci-men during the uniformity measurements. The resul
45、ts shall beaccurate to 60.1C (60.2F) with a total error of less than60.3C (60.5F) of the reading.6.7 Temperature Sensors, suitable for the room temperaturerange, such as thermocouples, are attached to the portions ofthe test specimens that will provide the best measurement ofthe ECC temperature. If
46、more than one specimen of identicalsize, design, and construction is tested simultaneously, it is notnecessary to monitor the temperature of all identical speci-mens.6.8 Voltage Cycling Unit, for imposing voltage cycles toalternately color and bleach the ECCs from a fully bleachedstate to the fully
47、colored state and back to the fully bleachedstate.6.9 Digital Camera, for taking photographs of the speci-mens.7. Test Specimen7.1 Test specimen size, design, and construction shall beestablished and specified by the user of this standard, exceptthe specimens shall be at least 250 by 250-mm.NOTE 3Co
48、nsideration should be given to the ultimate requirement fortesting specimens that are 355 6 6mmby5056 6 mm such as those usedin Test Methods E2188 and E2189, and for using heat-strengthened ortempered glass (see Specification C1048). Consult Section 5 in TestMethod E2188 for a description of test sp
49、ecimens and their preparation.NOTE 4The test method may also be used for smaller, prototype ECIGUs or EC laminated structures for measuring the uniformity of anabsorptive electrochromic coating (ECC) on a glazing surface.7.2 Six test specimens that are represented to be “identical”shall be supplied for measuring the uniformity of an absorptiveelectrochromic coating (ECC) on a glazing surface, which willultimately be one of two or more of the lites in a preassembledpermanently sealed insulating glass unit (IGU).3(See Appen-dix X1, Section X1.5.)7.3 The m
