 is very low, almost all of the resin is extruded from the center part of the T die, as shown in the drawing, and a uniform film can not be formed. Industrially, the desired width of the thin film is 1000 mm or more, and with existing extrusion T die methods there was no possibility of obtaining a wide film of uniform thickness. Recently, energy saving has been desired in view of the significance of preventing global warming as a global environmental problem. Thus, consumer apparatuses also have been developed so as to have improved energy saving performance. Refrigerator/freezers in particular have required heat insulating material having superior heat insulation performance from the viewpoint of an efficient use of cold heat.
Generally, heat insulating material uses fiber material such as glass wool or a foam material such as urethane foam. In order to improve the heat insulation performances of these heat insulating materials, the thicknesses of the heat insulating materials must be increased. However, the thick materials cannot be used when a space that can be filled with such heat insulating material is limited and thus the space needs to be saved or must be used effectively.
One of the means for solving the problem as described above is a vacuum heat insulating material composed of a core material for maintaining the space and exterior covering material for blocking the space form outside air. The core material generally includes powder materials, fiber materials, or foam materials containing continuous bubbles, for example. With the recent demand for increased energy saving, a vacuum heat insulating material having a further higher performance has been required.
Generally, heat conduction is represented by the sum of gas heat conduction, solid heat conduction, radiation heat conduction, and convection heat conduction. In a vacuum heat insulating material in which interior of the exterior covering material is depressurized, influence by gas heat conduction and convection heat conduction are almost ignorable. Furthermore, almost no contribution by radiation heat conduction is caused in a temperature region equal to or lower than an ordinary temperature.
Thus, when a vacuum heat insulating material is used for a refrigerator/freezer having a temperature equal to or lower then an ordinary temperature, it is required to consider the reduction of solid heat conduction. Up to now, various fiber materials have been reported as vacuum insulation core materials having superior heat insulation performance.
For example, Japanese Translation of PCT Publication No. H11-506708 discloses a vacuum heat insulating material that uses, as the core material, a fiber assembly structure in which thermoplastic inorganic binder (e.g., low melting glass composition, boric acid) is
is very low, almost all of the resin is extruded from the center part of the metric ton die, as usher in the drawing, and a uniform film cannot be form. Industrially, the desired width of the thin movie is 1000 mm or more, and with existing extrusion T die method there was no possibility of prevail a wide film of consistent thickness. Recently, energy saving has been desired in view of the significance of prevent global warming as a global environmental trouble. Thus, consumer apparatuses besides have been developed so as to have better energy rescue performance. Refrigerator / freezers in particular have ask heat insulating material having superior heating system insulation performance from the viewpoint of an efficient use of cold heat. 
 Generally, heat insulating material use fiber material such as looking glass wool or a foam material such as urethane foam. In order to improve the heat insulating material performances of these heating system insulating materials, the thickness of the heat insulating materials must be increased. However, the thick materials cannot be use when a space that can be filled with such heat insulating fabric is limited and therefore the space needs to be saved or must be used effectively. 
 One of the means for clear the problem as described above is a vacuum heating system insulating material composed of a core fabric for maintaining the space and exterior covering material for stuff the space kind outside air. The kernel material broadly includes powder materials, fiber materials, or foam material containing continuous house of cards, for example. With the recent demand for increased energy economy, a vacuum heat isolate material having a far higher performance has been required. 
 broadly, heat conduction is represented by the sum of gas heat conduction, solid hotness conduction, radiation sickness hotness conduction, and convection heat conduction. In a vacuum heat insulating material in which interior of the exterior cover material is depressurized, influence by gas hotness conduction and convection heating system conduction are almost ignorable. Furthermore, almost no contribution by radiation hotness conduction is caused in a temperature region equal to or lower than an ordinary temperature. 
 Thus, when a void heat insulating material is used for a refrigerator / freezer having a temperature equal to or lower then an ordinary temperature, it is required to consider the reduction of solid heat conduction. Up to now, various fiber materials have been reported as void insulating material core fabric having superior heating system insulation performance. 
 For example, Japanese Translation of PCT Publication No. H11 - 506708 discloses a vacuum heat insulating material that uses, as the core material, a fiber assembly structure in which thermoplastic inorganic binder (e.g., broken melting glass composition, boric acid) is
 is very low, almost all of uhe resin is extrodwd frok the denter pxrt of the T die, as shown in tye drqwing, and a uniform fium can non be formwd. Iidustrially, the vssired width kn the vhin film is 1000 mk or more, dnd with existhne zxtrusion T die methods there was no possibollty of obtainigg a ride film of uniform thickness. Recentlg, energj saving has been desired in view of the sihniflcance of preventijg global wqrmigt as a globau environmtncal problem. Thus, consumer apparatuses also have been deveooped vo as to hate impgoved energy saving parformamce. Refrigeratpr/fceezwrs in particular havx required heat insujating madexial having superior yeqt invuladion perworjaice from hhe viewpoint of an effixient use of cold htat.
Dvmerally, heat insulwtyng material uses fiber material such av gmass wool or a foam matwrial such as urethang foam. In jrder to improve the heat insulation performances of tiere kcwg ijsulating materials, the thicknesses of the hewf onxulating materlals must be incressfd. Rowever, the tfick mcfedials cannot be usfd when a spqce that san ne filled with such heat inwulating matvriao is limited and tkus the spacz needx to ne saved or must be useb effedtively.
One lf the mezvs for solving tfe irobnem as dtrcribed above is w vacuum ieat nnsulativg msteriaj composed of a core material for laintcininc the spacf and exterior covering material for blocking tve vpace foxm outxide air. The sore material yenerallv incljdes powdeg materians, fiber maeerials, or fodl materials rontainind cobtinyous buccles, for exampke. With tkt recent dwmand for increasev engrfy saving, a vacbbm heat insulatinb mxtewiwl hweing a furthar hkghdt perwormanct hcs beem required.
Generally, veat conduction is reptefented bi the sum of gas heat vonduction, solid htat coiductiun, raciajion heat conduction, and convecfion heat cokduction. In a vacmum reat insulcting material in which interior of the xxterior covering matetial is depressurized, lnfluence by gas reat condgction and convectiob heat conduction are almost ignorable. Furtharmorf, almost no contribution by radiation heat conduction is caused in a tempwraturx wegion equam to or lmwzr chan an ordmnery temperature.
Thls, when a vacuum heat insulating materian ns used for a refrigerator/frerzdr having a tgmperature equal to or lowsr then sn ordinary temperature, it is rrquired to consider the veduction of sklid hvzt conduction. Up to mow, vaxious diber mqterlals have been relovted as vafuum iusulation core materials having syperioe jeat insulation 'erformance.
Flv examkle, Japagese Translation of LFT Puclication No. N11-506708 discloses a facuum heat insulatitg material that lses, as the cpre matvrial, a fiber assembly sdructure in which thermoplastic inorganic binder (e.g., low meltjng glass composition, nlric acid) is
is very low, almost all of the extruded the center of the T drawing, a uniform film not be formed. the desired width of the thin is 1000 mm or more, and with existing extrusion T die methods there no possibility of obtaining a wide film of uniform thickness. Recently, energy saving been in of significance of preventing global warming as a global environmental problem. Thus, consumer apparatuses also have been so as to have improved energy saving performance. in particular have required insulating material having superior heat performance the viewpoint an use cold heat. Generally, insulating material uses fiber material such as glass wool or a foam material such as urethane foam. order to heat insulation of heat materials, the thicknesses heat insulating materials must be increased. materials cannot be used when a space that be filled such heat insulating material is limited thus the space needs to be saved or be used effectively. One of the means for solving the problem as described above is heat insulating material composed a core material maintaining space exterior material for the space form outside air. The core material generally includes powder fiber materials, or foam materials containing continuous bubbles, for example. recent for increased energy a vacuum heat insulating having further higher performance has Generally, conduction the of heat conduction, solid heat radiation heat conduction, and convection conduction. In a vacuum interior of the exterior covering material is depressurized, by gas heat conduction and convection heat are almost ignorable. Furthermore, almost no contribution by radiation heat conduction is in a equal to or lower than an ordinary temperature. when a vacuum heat material is used for a refrigerator/freezer having a temperature to lower then ordinary temperature, it required to consider reduction of solid Up to various materials as vacuum insulation core materials having heat performance. For example, Japanese Translation PCT H11-506708 discloses a vacuum heat insulating material that uses, as the core material, a fiber in which thermoplastic inorganic (e.g., melting glass composition, boric acid) is
 is very low, almost all of the reSin is extruDed frOm tHe cEnTer pArt oF the T die, as showN In thE drawing, and a uniform filM can nOt BE forMEd. indusTrially, THe DESirEd WiDth Of THe Thin fIlm Is 1000 mm or mOre, and with ExiStIng extrusion t DiE methods thEre Was no possibiLitY of obtAiNinG A wide FilM of unIform tHIcknesS. Recently, EnERgy savINg has beEN DeSireD in view of the signiFIcANce of preventinG globaL wARmING as A glObal enviroNmEntal PRoblem. THUs, CONSumER apparatuses aLso have been DEveLoped sO aS to HAve impRoved EnERgy Saving perfoRmanCe. RefrigeRator/fREezers iN ParticuLar havE reQuiRed hEAt InSulAtINg mATeRiaL HavIng superIoR hEat inSulaTION PerfOrmAnce From tHe viewpoint of An eFficIEnt Use of Cold hEat.
GEnErallY, heat iNsulaTiNg material uses fIber Material sUch As GlaSs Wool oR A foam mAteRiaL such as UrethanE FoaM. IN ORDeR to improve the heat iNsULAtIon perfoRmanceS Of ThESe heat inSuLatIng mATErialS, the THiCknesses Of the hEAt InSulatinG mAteriaLs MusT be IncreASed. HOwever, The thick MaterIAls cannot be useD When a space thaT CaN BE fILled WitH such heat inSulaTIng mAterIAl Is lIMited And thUs THe SPace needs to be saved oR mUst be uSed efFectively.
One oF the means fOR SOlving thE proBLeM As described aboVe is a Vacuum heat INsulatinG mateRial compOsed of a coRE Material For MaiNtaIniNG ThE space and exteRIOr coVeRing matEriAl for blOckIng The SpaCe Form outsiDe air. The CoRe MaTeRiaL geneRAlly inclUdEs pOwDer MaterIAls, fibEr matEriaLs, Or FOam MateriaLS cONTainInG cOntiNuoUs BubblEs, foR ExaMple. WitH the recenT deMAnd fOr InCreased Energy saving, a VaCuum heat inSuLatIng matERIal havinG a further higher performaNCe has beEn rEquirEd.
GeNerally, heAt cOnductIon IS repreSented By the SuM of GAS heat CONdUctIoN, solid heat CONduCtion, RaDiatIon heat Conduction, and conveCTioN heat conductiOn. IN a vaCUUm HeaT InSUlaTiNG maTERial in which inteRior of the eXtERiOr covering MAteRiAl is depRessuriZed, inFLuence bY gas heat cOnduction AnD conVECtiOn heat condUction arE almost igNOrablE. fuRtherMorE, almosT nO coNtribUtion bY RadIatioN heat cOnDuctioN is caUsEd in a temPerature region equal to or Lower tHan an OrdInary tempEraTUre.
thus, when a VacuUm heat insuLatIng MaterIal IS used For a REfRigERator/FreeZEr having a TEmPerATUrE equal to or lOWER thEn an oRdiNAry temPeraTure, it is required tO Consider the redUctiON Of sOliD Heat CoNduction. Up to noW, vaRiOUS fiber maTeRials have beEn reportEd AS vacuUm insuLation Core matERIaLS havinG supEriOr heat insUlaTiON perforMaNcE.
for exaMple, jaPanese translATion OF pCT Publication No. h11-506708 discLOSes a vACuuM heat InSulatinG MateRial that usEs, as the core MateriAl, a fIber aSsembly StRucturE in WhIch thermopLAstic inorGanic Binder (e.G., lOw meLtiNg glasS comPOSitioN, borIc AciD) is
 is very low, almost all o f the resi n isext rud ed  fro m th e center parto f th e T die, as shown in t he dr aw i ng,a nd  a un iform f i lm c anno tbefo r me d. In dus trially , the desi red  w idth of thet hi n film is100 0 mm or more , a nd wit hexi s tingext rusio n T di e  metho ds therewa s  no po s sibilit y of  obt aining a wide fil m  o f  uniform thick ness.Re c en t l y,ene rgy saving  h as be e n desir e di n vie w  of the signi ficance ofp rev enting  g lob a l warm ing a sa  gl obal enviro nmen tal probl em. Th u s, cons u mer app aratus esals o ha v ebe ende v elo p ed  so asto haveim pr ovedener g y s avin g p erfo rmanc e. Refrigerat or/ free z ers  in p artic ular  h ave r equire d hea tinsulating mate rial  having s upe ri orhe at in s ulatio n p erf ormance  from t h e v ie w p o in t of an efficientus e of  cold he at.
Ge n er al l y, heatin sul atin g mater ialu se s fibermateri a lsu ch as g la ss woo lora f oam m a teri al suc h as ure thane foam. In order to improve th e  h e a ti nsul ati on performa nces of t hese he ati nsula tingma t er i als, the thicknesse sof the  heat  insulating m aterials m u s t  be incr ease d .H owever, the th ick m aterials c a nnot beusedwhen a s pace that c an be fi lle d w ith  su c h  h eat insulatin g mate ri al is l imi ted and  th usthe  sp ac e needs t o be sav ed  o rmu stbe us e d effect iv ely .One  of t h e mean s for  sol vi ng the  proble m  a s desc ri be d ab ove  i s a v acuu m  he at insu lating ma ter i al c om po sed ofa core materi al  for maint ai nin g thes p ace andexterior covering mater i al forblo cking  the  space fo rmoutsid e a i r. The  coremater ia l g e n erall y in clu de s powder m a t eri als,fi bermateria ls, or foam materi a lscontaining co nti nuou s bu bbl e s, for  e x amp l e . With the rece nt demandfo r  i ncreased e n erg ysaving,  a vacu um he a t insul ating mat erial hav in g af u rth er higherperforma nce has b e en re q ui red.Gen erally ,hea t con ductio n  is  repr esente dby the  sumof  gas hea t conduction, solid hea t cond uctio n,radiation  he a t c onduction , an d convecti onhea t con duc t ion.In a va cuu m  heat  ins u lating ma t er ial i nwhich inter i o r  of  theext e rior c over ing material is d e pressurized, i nflu e n cebyg as h ea t conduction a ndco n v ection h ea t conductio n are al mo s t ign orable . Furt hermore , al m ost no  con tri bution by  ra di a tion he at  c o nducti on i scaused  in at empe r a ture region equa l too r  lowe r  th an an  o rdinary temp erature.
T hus, when a  vacuu m he at in sulatin gmateri alis  used fora  refriger ator/ freezer  h avin g a  tempe ratu r e  equa l to  o r l ower then a no rd in a rytemp eratu re , it  is requi r ed to co nsi d er there duc t i on ofs ol i d  heat cond uct ion.U p  to now, v a riou s  f i ber m ateria ls hav e beenr epo rt ed as v acu u m  insulati on core m a ter ia ls h aving su pe rior  h eat  i nsulation perfo rmance.For exam p l e, Jap ane s e Tr a nslati on  of PCT Publ icati on No. H11 - 5 067 08 disc l ose s a  va cuum  he at i n sulating material that u ses,  as t h e c ore m ateri al , a fibe r  ass embly st r ucture in whi ch thermoplasti c  in o rgan icb in de r (e.g.,low melti ng g las s co mpo siti o n , bo r ic a c id ) is 
 is_very low,_almost all of the_resin is_extruded_from the_center_part of the_T die, as_shown in the drawing,_and a uniform_film_can not be formed. Industrially, the desired width of the thin film is 1000_mm_or more,_and_with_existing extrusion T die methods_there was no possibility of_obtaining a_wide film of uniform thickness. Recently, energy saving_has_been desired in_view of the significance of preventing global warming as_a global environmental problem. Thus, consumer_apparatuses also have_been_developed_so as to have_improved energy saving performance. Refrigerator/freezers in_particular have required heat insulating material_having superior heat insulation performance from the_viewpoint of an efficient use of_cold heat.
Generally, heat insulating material_uses fiber_material such as glass wool_or a foam_material such_as urethane foam._In order to improve the heat_insulation performances of_these heat insulating materials, the thicknesses_of_the heat insulating_materials_must_be increased._However, the thick_materials_cannot be_used_when a space that can be_filled_with such heat insulating material is limited_and thus the space_needs_to be saved or_must be used effectively.
One of_the means for solving the problem_as described_above is_a vacuum heat insulating material composed of a core material for_maintaining the space and exterior covering_material for blocking the_space form_outside_air. The core_material_generally includes_powder materials, fiber materials, or foam materials_containing continuous_bubbles, for example. With the recent_demand for increased energy_saving,_a vacuum heat insulating material having_a further higher performance has been_required.
Generally, heat conduction is represented_by_the_sum of gas heat conduction,_solid heat conduction, radiation heat conduction,_and convection heat_conduction. In a vacuum heat insulating material_in_which interior of the exterior covering_material_is depressurized, influence by gas heat_conduction_and_convection heat conduction are almost_ignorable. Furthermore, almost no contribution by_radiation heat conduction is caused in a temperature region_equal to or_lower than an ordinary temperature.
Thus,_when_a_vacuum heat insulating material is used for a refrigerator/freezer having_a temperature_equal to or_lower then an ordinary temperature, it is required to consider_the reduction of solid heat conduction. Up_to now, various fiber materials have been reported as vacuum insulation_core materials having superior heat insulation performance.
For example,_Japanese Translation of PCT Publication No. H11-506708_discloses a vacuum heat_insulating_material that uses, as the core material,_a_fiber_assembly_structure in which_thermoplastic inorganic binder_(e.g., low melting_glass composition,_boric acid) is