,-------------------~_, ________ ,.. __ ~----~------~--~----~-------.. ~--·--------------·------~------~---·----~---~ i i i CALIFOR.i'ITA STA1'E UNIVERSITY, NORTHRIDGE PRESifF..INK D.RYING OF FABRICS IN I'l!CROWAVE OVEN \\ A thesis subm:i.tted in pa:r-tial satisfaetion of the requirements for the degree of Master of Science in Home Economies by Gertrud1;;1 Ml,)rrison .......He:i.ma..."l i '··· -··-··--- ----·----~--------.--· ---------·-····· ····- ··--····· . ~-. -'----.. ----------·--- The thesis of Gertrude N:orrison Hsiman is approved: Callfo:t<nia St.a.to U<:~.iversity, Nortr.ridge -------------·-·--·-·-··-----------------------, I I DEDICATION I I To I HOMEMAKERS OF AMERICA who like to experiment wi t.'l£ new ideas. I I! l ! ' l I l_________________ ·-- -------------- ---· ·····-· ---- -·--···-- -----· ----·-- ----------- ·----·-·-----------·-·---------- --------- iii ,~,·~--------·-· -~ I I ! ACKNOWLEDGNENTS I I wish to express my thanks and gratitude to all the people I whose collaboration with me hs.s made this study possible .. Special thanks go to l1iss Susan Richards for her contributions, suggestions and the loan of her books. I ,~ thanks also go to Mrs. Betty Bailey, :t<Irso Dorothy Blackr.llan, l and Dr. Marjory Joseph for their kind guidance. I l{v thanks is extended to my neighbor, Mrs .. Betty Mumford, ll-'ho I did all the typing for me. I And, last but by no means least, I thank lilY husband, I Eugene F.. Heilllan, whose financial support and continued cooperation i. ! made my entire gradu.~te studies program possible. i· i I ! i I iv ________ , _____________ __ I ! TABLE OF CONTENTS Page TITLE PAGE ••~•••••e•••••••••••••••••••••••••••••••••••• i .APPROVAL PAGE ......... c; ....... Ql •• ,.. ......... ., •• ~ ••••• e • o ..... ii DEDICATIOt1 o ............................ e •••••••••••••• ~. iii ACKNOWLEDGMENTS ••••••••••••••~•••••••~•••e••••o•••••••• iv UST OF TABlES .......... CJ -ft •• •-• ••-• •• (t .................... vii LIST OF li'IGUR.ES viii ABSTR.t\cr •••••••••••••••••••••• ~ ••••••••••••• s- •-• •• .,. •. "'• ix CHAPTER I. INTROJ.lJ CIT ON 1 Objective •••••s•~•·•••••••e•••••~••••••~•••• 1 Justific~tion e~···········-~···8·~·········· 1 Hypotheses 2 Assu."Ylptions 3 Limitations •••e••~•••••~~'••••••••~~•••••••• 3 Definition of Terms •••••••••o••••••••••••••• 4 II. REVIE"~!l OF LITERATURE ................................. 5 Shrj.nksge 5 Nicrowave 17 IIL PROCEDTjP~k,; •• ~ ..... " , •• .- ••••• • •••., • "' •• 4t ..... ~ •• .., ••• 24 Pilot Study by Author ............ , ............. ., ... 24 Test Procodure 26 Oollf)ction eJJ.d Evaluation of Data • , ... ,. ...... ., 32 ! ----·-------·------··--·------· ---·-----·---··-···--·-··-·---·- --------' v r-·------·---------------··----------·- l 1 I IV. TEST RESULTS AND-OBSERVATIONS •••••••••••••••••• J5 Test Results ~oeeee••~••••••••••••••••••••••• J5 Observations •••••••••••••••••••••••••••••••• J8 v. CONCLUSIONS .AJ.~D RECOMMENDATIONS •••••••••• •• •••• 4J SELECTED BIBLIOGRAPHY ................................... 45 I 1 I APPEND[XES ••••••••••••••••••••••••••••••••••••••••••••• 48 I- Appendix A. Details -of Specimen Holder • ••••••• 49 Appendix B. Automatic Washl:ng Machine •• p ' Op eraw~ng arame~ers ~••••••••••••• .50 Appendix C. Dr,ying Apparatus Parameters ••••••• 51 ~mensional Changes of Selected Fabrl cs after Laundering Di"ied I under Three Conditions ............. 52 I Appendix E. ·- Area Shrinkage after One and Five i Lau.ndering a..~d Drying Cycles of !· I Selected Fabrics •••••••••••••••••• 53 ! ·i l ! ,------··-------- .l 1 I I LIST OF TABLES I Table Page 1. Elastic Properties of Various Fibers at Selected Extensions •e••••••e••~•e••••••••••••••••••••••••• 7 2. Percent Swelling in Fiber D'lamete:r and Length of Selected r~bers ~····•••••••-••••••~•·•••••••••••• 9 3. Fabric Description of Selected Interfacing and Underlining Woven Fabrics ••••~••••••••••••••••••• 28 4. Laundering Conditions for Selected Intarfa~lng and Underlining Fabric ·-··••••••••••••••••••••••• 30 .5. "F" Table after First Test cycle •••eeGe•••••••••• 39 6. "F" Table after Fifth Test CYcle ···············~· 39 !. i ! I I i t -·--·---~--- ~-- --- --~·-· -------------- .... ~----------"·------- ----·----- . -- ·------- ------------. ---- ------------------"·--- ·-- ________________________________________ ___.i vii --------·------------------------------- IJ:ST OF FIGURES I j :Figure Page 1. Typical Stress-strain CUrve of Textile Fibers ••••••••• 6 2. Approrlm!ition of Yarn Cross-section Showing Fibers l and Interfiber Space •••••••••••••••••••••••••••••••••• 10 I J. Forces Acting on Yarn AB Assembled into a Plain I Weave FabriC ••••••••••••••••••••••••••••••••ft•<i)o········ 11 I 4. Crimp Exchange Due to Applied Tension (t) ••••••••••••• 12 I I 5. A Geometric Explanation of Cloth Shrinkage •••••••••••• 13 I 6. The Effect of Fabric Cover Factor on Fabric I LalL~dering Shrinkage •••••••e~•·••••••••••e•••••~•••••• 1.3 of 7. The Effect Weave T;y-pe(Constant Cover Factor) I upon Fabric laundering Shrinkage o•••••••••••~••••••••• 14 ! 8. The UHF Spectrum Indicating Relative Position of the F~equency at wr~ch }ftcrowave Ovens Operate •••o•••• 18 9. Interaction Between Microwaves and Surrounding · Medi.a ••• ~ •••• : * ••• o •••••••••• o ••• ~ • ~ ...... "' ............. 18 lO. Components of a M:tc.ro\#rave Oven ........................... 21 11. Average Lengthwise Shrinkage a11d Average Percent Shrinkage of 10 x 10-inch Specimens after First and Fifth Laundering and Drying ~Jcles •••••••••••••••~ 12. Average \?ldthw-lse Shrinkage and Average Percent Shrink2.ge of 10 x 10-:l.nch Sp.ecimens after }l~rst and Fifth Laundering and Dr7lng Cycles ••••~••••••••••• Average Area Shrinkage of 10 x lOw.inch Specimens I after First and Fifth Laundering and Drying G.vcles •••• 40 I I i I I I L ____________ -------------------------- ---------------- --------- ------------------------ viii I I ABSTRAC! PRESHRINK DRYING OF FABRICS IN MICROWAVE OVEN by Gertrude M. Heiman Master of Science in Home Economics June , 1974 The object of this research was to determine the effectiveness JofI a domestic microwave oven in the preshrink drying of selected I !interfacing and underlining fabrics. A comparative study was I . I jconducted to determine whether the method of drying (i.e., tumble I idry, mi.crowave oven dry, or room-line dry) does significantly affect !the dimensional changes occur in the preshrinking of selected I ~hich I I iinterfaclng and underlin.i.ng woven fa.brics. I i The fabrics for this study were selected as representative of I I ;those available to consumers in Southern California4 These fabrics I iincluded one cotton, one rayon1 one polyester, two polyester-cotton I I ;blends, one rayon-polyester bland, and one rayon•polyester-goat ha:lr i !blend.. All fabrics tv8re of plain weave construction that did not 11•equirt) ironing when subjected t.o hom.e laundry processes. Specimens were laundered in four-pou.nd loads ac(!O:rding to I ·:procedures typic.:il of those us9d in the home for preshrinking iptn•poses and ace·ording to !HJC:;:>pted test. procedures.. Specilnens werl:'t ! i 1......---~~---·--·- ·--·-·------------··---------- .. ix r:::::.::~::::g~.t::i:,:::::::d~ng p~~dur~--t~ble dry, ------~ . I I Five laundering and drying cycles were carried out. Specimens 1 I I 1were measured before laundering and.after the first and fifth 1 laundering and dry:!.ng cycles. 1,, I The changes in dimensions indicated that in the preshrink I i 1dryi:ng of. selected interfacing and U.""lderlining fabrics, the method I iof d..."7ing, whether by tumble dryer, microwave oven, or room-line I !dry, does significantly affect tha dimensional changes which occur. !The microwave oven is not recommended for the preshrink drying of I i !fabrics. ·I I I,. I I I I l ·j i ! i ! L--·---------~--- ---- --·- ----------- -----~-----~---· -- --------------~ -- X r ·-----------· ·--------------. I ·j ' I I aiAPTER I INTROOOCTION In a reeent publication from Litton Microwave Cooking Center, I !Ludvigson suggested that approximately a yard of fabric could be I ; preshrunk in a. domestic microwave oven (9:63). A review of the I I textile literature disclosed that microwaves were being used in lthe'processing o£ textiles to dr,y dyes a.nd finishing agents (27:6). I l However, no information was found rel.ating to the preshrinking of I i :f'abries With a domestic microwave oven. I \ j£P~cti~ I 1 The objective of this study was to determine the effectiveness i i of a microvrave oven in the preshrink drying of s-elected interfacing 'j and underlining fabrics. l I !,_...........,___ Justification I . I A problem for the home sewer is the tgndenc,y of textile I ! materials to shrlnk or stretch dUJ.-ing the first few launderings and subsequent dr·yings.. Such dimensional changes t and ospecia~ly shrinkage, in apparel fabric .may render a fitted garment uncomfortable and sonH.:rtimes even useless. ··A lengthwise shrinkage of only 1.5 percent ca..n cause a change in dress size .. Textile m~~ufacturers do treat fabrics with various mechanical .a:nd e.i1e.r.'..ica.1 finishes to p:ceve:nt e.ha.nges in fabric di.IUensions .............------·- ................................................- .............................................................. --....................... - ... ·- 1 F"'deral Trade O.;mmiss:i.on (20: 31'1) .. T·o a v·o:td the i:m::-onvenien:ca of f<J.br·:i.c dimt:msional ch::mges in 1~otions before they ar~1 cut (10:98). It is cu:ricms that many necessary r,;l ti.1. prf2•r.>b.runk goud.s.. Clothing const.ructicn