1、Designation:D144707(Reapproved 2021)Standard Test Method forLength and Length Uniformity of Cotton Fibers byPhotoelectric Measurement1This standard is issued under the fixed designation D1447;the number immediately following the designation indicates the year oforiginal adoption or,in the case of re
2、vision,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 This test method covers the measurement of the lengthand length uniformity of cotton fibers by use of ph
3、otoelectricmeasurement.The test method is applicable to fibers takenfrom raw or partially processed cotton(up to card mat)or sometypes of cotton waste,but not to fibers from blends of cottonwith other fibers or to fibers recovered from cotton yarns,fabrics or to 100%synthetic fibers.1.2 This test me
4、thod is especially adapted for determiningthe length and length uniformity of cotton fibers by models ofthe Digital Fibrograph,hereafter referred to as Fibrograph.NOTE1Instructions for the use of Manual and Servo FibrographModels were included in the text of Test Method D1447 in 1971 andprevious edi
5、tions.NOTE2For other methods covering the measurement of the length ofcotton fibers refer to Test Method D1440.1.3 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.4 This standard does not purport to address all of thesafety con
6、cerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accor-dance with inte
7、rnationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:2D123 Ter
8、minology Relating to TextilesD1440 Test Method for Length and Length Distribution ofCotton Fibers(Array Method)D1441 Practice for Sampling Cotton Fibers for TestingD1776 Practice for Conditioning and Testing TextilesD3025 Practice for Standardizing Cotton Fiber Test Resultsby Use of Calibration Cott
9、on StandardsD7139 Terminology for Cotton Fibers3.Terminology3.1 For all terminology related to D13.11,refer to Termi-nology D7139.3.1.1 The following terms are relevant to this standard:fibrogram,mean length,uniformity index,upper-half-meanlength.3.2 For all other terminology related to textiles,ref
10、er toTerminology D123.4.Summary of Test Method4.1 Fibers are placed on comb(s)in such a way that they arecaught at random points along their lengths to form a beard.The beard is scanned photoelectrically from base to tip,theamount of light passing through the beard being used as ameasure of the numb
11、er of fibers that extend various distancesfrom the comb(s).4.2 The Fibrograph shows the amount and the lengthreadings from the Fibrogram being sensed on separate dials.5.Significance and Use5.1 This test method is considered satisfactory for accep-tance testing when the levels of the laboratories ar
12、e controlledby the use of the same reference standard cotton samplesbecause the current estimates of between-laboratory precisionare acceptable under these conditions.If there are differencesof practical significance between reported test results for twolaboratories(or more),comparative tests should
13、 be performedto determine if there is a statistical bias between them,usingcompetent statistical assistance.As a minimum,ensure the testsamples to be used are as homogeneous as possible,are drawnfrom the material from which the disparate test results wereobtained,and are randomly assigned in equal n
14、umbers to eachlaboratory for testing.The test from the two laboratories shouldbe compared using a statistical test for unpaired data,at a1This test method is under the jurisdiction ofASTM Committee D13 on Textilesand is the direct responsibility of Subcommittee D13.11 on Cotton Fibers.Current editio
15、n approved Jan.1,2021.Published January 2021.Originallyapproved in 1955.Last previous edition approved in 2012 as D1447 07(2021)1.DOI:10.1520/D1447-07R21.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStand
16、ards 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 StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)
