1、Designation: D4969 07 (Reapproved 2012)D4969 17Standard Specification forPolytetrafluoroethylene(PTFE) Coated Glass Fabric1This standard is issued under the fixed designation D4969; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, t
2、he 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. Scope*1.1 This specification covers glass fabric impregnated, coated, and sintered on both sides with PTFE to a nomi
3、nal thickness of0.318 mm (0.015 in.) or less.1.2 The PTFE-coated glass fabric is for electrical, chemical, and mechanical uses.1.3 The PTFE-coated glass fabric of this specification does not pertain to structural fabric, single-sided PTFE coatings, ormaterials used for laminates.1.4 The values state
4、d in SI units as detailed in IEEE/ASTM SI-10.NOTE 1There is no ISO standard that covers information included in this specification. The dielectric test is mentioned in ISO 12086-2 andISO 130001 and 2.1.5 This international standard was developed in accordance with internationally recognized principl
5、es on standardizationestablished in the Decision on Principles for the Development of International Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D123 Terminology Relating to Textiles
6、D149 Test Method for Dielectric Breakdown Voltage and Dielectric Strength of Solid Electrical Insulating Materials atCommercial Power FrequenciesD257 Test Methods for DC Resistance or Conductance of Insulating MaterialsD374 Test Methods for Thickness of Solid Electrical Insulation (Metric) D0374_D03
7、74MD579 Specification for Greige Woven Glass FabricsD618 Practice for Conditioning Plastics for TestingD737 Test Method for Air Permeability of Textile FabricsD751 Test Methods for Coated FabricsD883 Terminology Relating to PlasticsD902 Test Methods for Flexible Resin-Coated Glass Fabrics and Glass
8、Fabric Tapes Used for Electrical InsulationD1424 Test Method for Tearing Strength of Fabrics by Falling-Pendulum (Elmendorf-Type) ApparatusD3892 Practice for Packaging/Packing of PlasticsD4441 Specification for Aqueous Dispersions of PolytetrafluoroethyleneIEEE/ASTM SI-10 Standard for Use of the Int
9、ernational System of Units (SI): The Modern Metric System2.2 ISO Standard:3ISO 12086-2 PlasticsFluoropolymer Dispersions and Moulding and Extrusion MaterialsPart 2: Preparation of TestSpecimens and Determination of PropertiesISO 130001 and 2 PlasticsPolytetrafluoroethylene (PTFE) Semi-Finished Produ
10、cts3. Terminology3.1 Definitions:1 This specification is under the jurisdiction of Committee D20 on Plastics and is the direct responsibility of Subcommittee D20.15 on Thermoplastic Materials.Current edition approved April 1, 2012Sept. 1, 2017. Published June 2012September 2017. Originally approved
11、in 1989. Last previous edition approved in 20072012 asD4969 07.D4969 07(2012). DOI: 10.1520/D4969-07R12.10.1520/D4969-17.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer
12、 to the standards Document Summary page on the ASTM website.3 Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http:/www.ansi.org.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indicatio
13、n of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be consid
14、ered the official document.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States13.1.1 Definitions of terms relating to plastics used in this specification shall be in accorda
15、nce with Definitions D883. Definitionsof terms relating to textiles used in this specification shall be in accordance with Terminology D123.3.1.2 structural fabricPTFE-coated fabric to a thickness of greater than 0.381 mm (0.015 in.).3.1.3 lot, none production run or a uniform blend of two or more p
16、roduction runs.4. Classification4.1 There shall be six types of PTFE-coated glass fabrics as described in Table 1.4.2 Use a one-line system to specify materials covered by this specification. The system uses redefined cells to refer to specificaspects of this specification, as illustrated below as f
17、ollows.SpecificationStandard NumberBlockType Grade Class SpecialNotesExample: ASTM D4969-XX IV ,For this example, the line call out would be: ASTM D4969 XX, IV , Porosity 1530 CFM, and would specify a Type IVporous product which is referenced in Table 1 with no grade or class since these subcategori
18、es do not appear in this specification.A comma is used as the separator between the standard number and the type. Separators are not needed between the type, grade,and class because they are, in turn, Roman numerals, Arabic digits, and uppercase letters, as provided in Section B8 of Form andStyle fo
19、r ASTM Standards. Provision for “Special Notes” is included so that other information can be provided when required. Anexample would be in this specification where porosity would be defined as 1530 CFM. When special notes are used, theyshouldshall be preceded by a comma.5. Materials and Manufacture5
20、.1 Glass FabricThe base material used in the manufacture of the products of this specification shall be a woven glass fabricproduced in accordance with Specification D579. A guideline for generally acceptable substrate fabrics for the common thicknessof PTFE/glass fabric products is given in Table 2
21、.5.2 CoatingThe glass fabric is impregnated or coated with polytetrafluoroethylene in accordance with Specification D4441.When necessary, use additives to aid the dispersion to achieve the required properties and performance of the final product.6. Physical Requirements6.1 The coating shall penetrat
22、e and adhere to the fabric and shall be substantially free of wrinkles, creases, blisters, and otherimperfections.6.2 Color:6.2.1 The material will have a natural color that varies from off-white to dark brown when viewed by the unaided eye. The usualcolor is tan.6.2.2 If color is required by the cu
23、stomer, specify it.6.2.3 Color will be uniform from roll to roll within a lot.6.2.4 Other colors for products that contain pigments, fillers, and additives will be agreed upon between the suppliers and thecustomers.6.3 ThicknessThe thickness of the glass fabric is dependent on glass style and percen
24、t PTFE coating. Tolerances are typically610 % of the finished thickness. Thickness shall be tested in accordance with Test Methods D374.NOTE 2Typically, glass and coated glass products are manufactured to a weight per unit area.6.4 Breaking StrengthWhen tested in accordance with Methods D902, the br
25、eaking strength shall be at least 80 % of thespecified value stated in Table 6 of Specification D579.TABLE 1 PTFE-Coated Glass Fabric TypesType Name General Description and Common ApplicationI Premium Smooth, defect-free, primarily used as a dielectric application, release sheet,and Military Specifi
26、cation material.II Standard Regular-grade material primarily used for mechanical applications wheretemperature and easy-release characteristics are required.III Mechanical Regular-grade material primarily used for mechanical applications wheresmoothness is not a critical requirement.IV Porous Permea
27、ble material, with a range of porosity primarily used as a release sheet inmolding.V Tear resistant Smooth, flexible, and tear-resistant material for mechanical applications requiringflexible materials.VI Conductive Regular-grade material primarily used for static discharge.D4969 172NOTE 3Reduction
28、of tensile strength is due to added heat required for coating.6.5 Edge Tear Strength(Elmendorf) Tears shall be tested in accordance with Test Method D1424. Tear values are dependentupon glass style and additives added to the PTFE. Typical Tear Resistant (Type 5) products exhibit two times the values
29、 of theircounterparts. Conductive (Type 6) products exhibit one half the values of their counterparts. Test values and tolerances shall bedetermined by the supplier and the customer.6.6 MassA sample shall be prepared in accordance with Method D751. The amount of PTFE added shall be agreed uponbetwee
30、n the customer and the supplier and shall have a tolerance of 65 % of the total coated product weight.6.7 WidthsThe coated glass fabric shall be furnished in the widths and tolerances indicated in Table 3, when tested inaccordance with Method D751.6.8 ConductivityFor Type 6 material, conductivity sh
31、all be tested in accordance with Test Methods D257, using the Flat MetalPlate Method, and a comparison bridge. Material shall be deemed conductive when the resistivity is below 106 /square.6.9 Dielectric BreakdownType I only.6.9.1 Dielectric Breakdown VoltageWhen tested in accordance with Test Metho
32、ds D149 and Methods D902, with a 14-in.electrode, the dielectric breakdown voltage for the various thickness shall be as specified in Table 4.6.9.2 Dielectric Breakdown After HeatingAfter exposure to a temperature of 150C (302F) for 12 h, the average value offive samples shall be not less than 80 %
33、of the value determined before exposure.6.10 LengthThe length of the products of this specification shall be furnished in rolls or in sheets. Typical roll lengths are 40to 80 m (36 to 72 (43.7 to 87.5 yd) and 16 to 65 m (17.5 to 71.1 yd).6.11 Percent PTFEWhen required in the purchase order or contra
34、ct, the supplier shall provide the ratio by weight of thefluoropolymer coating to the total weight of the finished product using the following formula:total weight2bare glass weighttotal weight 3100 (1)where:total weight = as calculated in 6.6 of this specification.bare glass weight = as specified i
35、n Table 6 of Specification D579.6.12 Smoothness, Type I Material Smoothness shall be tested using a profilometer, or equivalent, capable of measuring theaverage roughness to the nearest microinch.6.12.1 Three samples shall be measured across the width at a 45 angle to the weave.The length of measure
36、ment shall be greaterthan 12 in.6.12.2 Record the reading from each measurement. Average the recorded results and report the average value in microinches.Smoothness values and tolerances shall be determined between the customer and the supplier.6.13 Porosity, Type IV MaterialPorosity shall be measur
37、ed in accordance with Test Method D737.TABLE 2 Acceptable Substrate Fabrics for Common Thickness ofPTFE Glass Fabric ProductsPTFE/Glass Fabrics Thickness. Generally Acceptable Woven GlassFabrics Style Numbermm (in.)0.051 (0.002) 104, 1060.076 (0.003) 108, 10800.102 (0.004) 112, 113, 21130.127 (0.005
38、) 116, 1165, 2116, 21650.152 (0.006) 116, 1165, 21160.203 (0.008) 125, 1528, 76280.254 (0.010) 128, 1528, 76280.356 (0.014) 141, 11420.356 (0.014) 141, 1142, 3781TABLE 3 Widths of PTFE-Coated Glass FabricNominal Widths Tolerancesmm (in.) mm (in.)3.17 to 12.7 (18 to 12) 0.397 (164)12.7 to 38.1 (12 to
39、 12) 0.794 (132)12.7 to 38.1 (12 to 112) 0.794 (132)38.1 to 76.2 (112 to 3) 1.587 (116)76.2 to 305 (3 to 12) 1.411 (18 )305 or greater (12 or greater) 6.35 (14 )D4969 1736.13.1 Porosity values and tolerances shall be determined between the customer and the supplier.7. Sampling7.1 Sampling shall be s
40、tatistically adequate to satisfy the requirements of 9.1.7.2 A random sample of roll or sheet shall be selected from each lot for visual, dimensional, and weight inspection.7.3 Visual InspectionAt least ten yards of the roll selected in accordance with 7.2 shall be unwound and inspected forcomplianc
41、e with 6.1.8. Conditioning and Test Conditions8.1 ConditioningBecause of the nature of these materials, conditioning has little merit; however, if conditioning is desired,use Procedure A of Method D618 for a period of 4 h prior to test.8.2 Test ConditionsUnless otherwise specified, conduct tests at
42、the standard laboratory temperature of 23 6 3C (68 to 79F)and relative humidity of 50 to 70 %.9. Conformance9.1 Due to the various suppliers and customer requirements, color, thickness, breaking strength, edge tear, conductivity, percentPTFE, smoothness, and porosity can not be realistically specifi
43、ed in a table. However, when measuring these properties, these testmethods must be used to ensure consistency in measurements and comparisons between and among suppliers and users.9.2 Upon request, a manufacturers certification that the material was manufactured and tested in accordance with thisspe
44、cification together with a report of the test results shall be furnished.10. Packaging and Package Marking10.1 PackagingThe materials shall be packaged in standard commercial containers constructed so as to ensure acceptance bycommon carrier, unless otherwise specified in the contract or order.10.2
45、Package MarkingShipping containers shall be marked with the name of the material, type, thickness, and quantitycontained therein. Each roll or package of sheets shall be marked to designate type and lot number.10.3 All packaging and marking provisions of Practice D3892 shall apply to this specificat
46、ion.11. Keywords11.1 dispersion; fluorocarbon; fluoropolymers; polymer coating; polytetrafluoroethylene; PTFE; PTFE coated glass fabricTABLE 4 Electrical Properties of PTFE-Coated Glass FabricAType Thickness Dielectric Breakdownmm (in.) Volts, minType 1 0.051 (0.002) 10000.076 (0.003) 25000.102 (0.0
47、04) 33000.127 (0.005) 39000.152 (0.006) 43000.203 (0.008) 47000.054 (0.010) 52000.356 (0.014) 7500A Only Type 1 is applicable.D4969 174SUMMARY OF CHANGESCommittee D20 has identified the location of selected changes to this standard since the last issue(D4969 - 02D4969 - 07)(2012) that may impact the
48、 use of this standard. (March(September 1, 2007)2017)(1) RevisedAdded Note 1style 3781 to Table 2.(2) Fixed typo in line 2 of Table 3. Read as 12 in. not 1-12 in.(3) Added additional typical length to 6.10.ASTM International takes no position respecting the validity of any patent rights asserted in
49、connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn.Your comments are invited either for revision of this standard or for additional standard
