OAR Box 1413 

Prepped by Ollie Stewart 

Document Number: 

49) 11-1-49 

Docket Number: 

A-94-52 

Printed 7/9/2008 3:11:22 PM Sheet 49 of 114 

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SCJNI BT-U3 riU TAItlNl SALLS /-12-3b ; 15=25 

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19199410234:#30/50 

United States Patent m 

Scher et sl. 

Ill 

US005IB360OA 

[ii) Patent Number: 

[45] Date of Patent: 

5,183,600 -rpnya 

Feb. 2,1993

 M

~

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[54] METHOD AND APPARATUS FOR 

CONTINUOUS CASTING OP 

POLYMERIZABLE MATERIAL 

pS] Inventors: Herbm L Seher.Tfteivillc; Israel S. 

. Ihgar, RaadallKown; Richard R. 

Baehr, Jr, AnntpoHi. all of Md. • 

m 

(21) 

PJJ 

rsu 

IS2) 

Assignee: Nevamar Gorpomden, Odenton, Md. 

AppL No.: 732,662 

Filed: JsLI«,19*l 

I M. CL* ««~., 

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B39C as/io 

-...264/26; 264/73; 

264/145; 264/148; 264/216; 264/236; 264/347; 

264/331.18; 264/342 RE: 425/174.1 ft 

• 425/?24j 425/445:425/75 

[58] FWdofS««h 264/216,13,22,212, 

264/26.331.18,166,16S. 148, 236,73,75,347, 

243,342 RE. 143; 429/1744 R, 174.1 E, 174.4, 

445,174.6,224,75 

[56] Rcfercncea-Chcd 

US. PATENT DOCUMENTS 

2.136422 

1379,24a 

isoa.-m 

1979,131 

2403,741 

2.607.081 

X663J00 

2.U2J75 

3.049.761 

3.09U»1» 

3£16J49 

3437.674 

MIU46 

3419J17 

3421,131 

3.329425 

3,392.882 

3,600.490 

3463.493 

11/1931 

6/1943 

1/1946 

3/1930 

12/1931 

7/1992 

1/1932 

12/1993 

2/1992 

I/I962 

6/1963 

11/1969 

1/1967 

•1/1970 

7/1970 

9/1970 

9/1970 

7/I9T1 

6/1971 

5/1972-

FIdds. 

wnHaw. 

244/236 

,264m 

Burnett «al. 264/22 

SdMcdfltaL. 

Taylor — — 264/169 

Mriff m, tl, 

Imbcrt a iL* . 429/174.1 R 

Yakubik. 

Haekert. 

laeoto - 264/29 

Smncbom « aL -— — 264/236 

OuggilH. 

Deacfc ^ r ^—_ _ 425/174.1 K 

DugfJm. 

Duggbtt. 

Menu. 

BtDlatdeyciaL . 

WillCT •«»••»•>—M«WMI»MMMMWa awf #7 9 

3.101,407 

U»MH 

3J72.I97 

349M24 

3,923,941 

j.978.171 

V9U.0M 

4j00146t 

4J0IM42 

4,113.161 

4.166AM 

4J2I.299 

429MI3 

4414/06 

4.425.217 

4^26,117 

4.710333 

4^39,129 

4/1974 

6/197* 

J/1973 

7/1979 

9/1975 

11/1973 

1/1976 

10/1976 

1/1977 

4/1977 

1/1979 

1/19(0 

9/1980 

11/1981 

2/1982 

9/1*83 

1/19M 

12/1916 

12/1987 

6/19U 

OoUswonhyaiil.. 

fioncUrk at al. . 

XatostaL . 

Kato etal. . 

Henna . 

Weaver. 

OtUaeaai. 

Rate etaL . 

MeUmctal. 

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BredUyctaL. 

Sdbennra • 

Teei*. 

Tfereaeti eL . 

Until-. 

HotcttaL . 

ManbodctaL 

Ida. 

FOREIGN PATENT DOCUMENTS 

0036819 9/1911 Earapen PW. 6ft . 

0246806 11/1987 Ewopew Pat Off.. 

3943266 6/1986 Fed. Rep. of Genuity . 

1491437 7/1967 FiaoM . 

" 1497708 9/1967 

4949163 11/1974 

33-140362 9/1971 Japan. 

1366385 9/1974 United Xhfdon — — 423/1716 

Primary JSmmMeN-JefFery Thuriow • 

Attomty. Agtm er f!rm-4oat% Day, Reavis* Fogue 

<? 

[ST] ABSTRACT 

A method and apparatus for oortamoat cadtaf of polyi 

mrinblt aalsrielfthat shrink during polymeriiation 

include* rapidly heating a moving matrix sshstaotially 

•nUbrmly thranghoat itt eross section by radio ft*-" 

fpency^cocrgy to initiate polymerisation aod maintain' 

qg die matrix thereafter fa substantial (banal Isolation 

such that substantially adiabaOe polymerisation ocean. 

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lbiaa41U2i!4:#31/&U 

U.S. Patent Feb. 2,1993 Sheet 1 of 5 5,183,600 

PF«JIM niiPR . MONOMERS. RESIN FILLER MODIFIERS, ETC. 

PIGMENTS • 

CATALYSTS 

SYSTEM" 

COMPOUNDING 

SECTION 

CAST UQUID MATRIX ONTO A MOVING CARRIER 

WEB AND ESTABUSH LEVEL SURFACE 

I 

HEAT MATRIX TO A POLYMERIZATION 

TEMPERATURE THAT PERMITS GELUNG 

WITHOUT SHRINKAGE. 

HOLD AT A SOAKING TEMPERATURE 

THAT IS CLOSE TO THE 

TEMPERATURE ATTAINED FROM 

THE AUTOGENIC REACTION UNDER 

ADIABATIC CONDITIONS 

Rg.1 

COOL SHEETS TO ROOM 

TEMPERATURE 

9, 
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JUVI DI*UO n v THIDM iALLi : /-12-3tj : lb'-25 '• 19193410234:#32/50 

U.S. Patent Feb. 2,1993 Sheet 2 of 5 5,183,600 
Ui 

CONVENTIONAL HEATING OF UQUID MATRIX BY CONDUCTION 

-XL . 

TEMPERATURE 

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RAD10 FREQUENCY HEATING OF LIQUID MATRIX 

(Woolly Uniform Rodtotion Field) 

DURATION 

OF 

RADIATION 

TEMPERATURE 

TEMPERATUREv 

OF MATRIX j 

VISCOSITY 

Rg.4 

D SETTING PERIOD OF FAIER OR 

PARTICLES (Much Shorter Period 

with Radio Frequency Heating) 

TIME' 

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ONE EMBODIMENT OF TYPICAL HEATING SEQUENCE 

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TEMPERATURE 

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TEMPERATURE RISE DUE TO 

EXOTHERMIC REACTION 

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HEATING 

PERIOD 

GELLING 

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OPTIONAL 

SECOND 

HEATING 

PERIOD 

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TIME- -••» 0 

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GEUMG TEMPERATURE fc CATALYST ACTIVATION TEMPERATURE 

CURING TEMPERATURE (approidmote temperature attained 

by matrix reacting under adrabatfc conditions) 

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of reaction and actually it cooled by dissipating beal 

METHOD AND APPARATUS POR CONTINUOUS back to that environment. This proeea continues until 

CASTING OF POLYMERI&ABLE MATERIAL substantially aU of tbe unsaturated bonds of die min 

„.~«,«»,,,„.,~ ~«. •.. « ..».^v-.»^». "^ monomer components ate consumed and tBe resin 

BACKGROUND OF THB INVENTION 5 is cured. Ibe mold h then opened after oopliof and a *' 

JL Rdd ofthe Invention pond ctf decomh* » ^ 

Tbe present invention relates to a new method and plained bebw^tfepre^i 

apparatus far continuously casting certain thick sheet • ttm>d j# ^ and 

materials sometimes used as turfade overlay, bat which nuybtlw ^ 

also eaa.be used, without underlay, suchas fbr a stand- !-* Such a batch process- has rigniflcanca ahoilonndngk 

alone restaurant table top. More particularly, the pm- Rh alow and inelQe^nquirini a great deal of matecot invention relates to tn improved method and appa- rial handling equipment Moreover, it presents dgnifi* 

ntns for continuously c-tttingpolymeric materials cant problems with contra^ dwmatrm'uniformity tn • 

whfchihrink during polymaization. die mold, particularly where decorative e*rtiala are 

a Description of die Prior Art

 ls

 used in dm matrix. For ekampb, flow patterns sad con-

. Polymeric materials such i s thermosettmg reaSns, veetioo ourenta in the liquid matrix which may mult 

diennophsric resins; acrylic resins and die like aie com- during pumping or during die beating and early stage* 

manly, used.aa ratface txrverag materials. Sheet* of of polymerization can resuh in aonunJibnnlty of the 

diese materials nre used ssdefcqredve finishing materials dacomdve pattern, b addition, snch a bitch process 

ianewbolldiBBconstntctioBa^inrcBwdeantforsuch M .|w»enM-Mgi>tfieM^i «mwflr<rtJ^|ytnffmattiwh nw 

applications as bathroom vanity tops, kitchen oonhter ltt«edv4th proper uniformity and, dms, does not poly* 

tops, furniture components.restaurant.table* wall pan- nerf^ tt ft, „„* rate throughont the meld cavity. 

ding and other uses. TTte sheets <ao be made of plain Tht result ( » be kicaliiedshriiddngwAlch may cnaie 

*M crion>ercan be patterned to hav tba apomiaaec erneks or lean h Uie final eundmMeiU 

of maiUe, granite or other patterns or textunl decora* « dues residual stresses. -

tion. The sheeta often are loaded widi decorative parti* Bnwui nrtar mm m h».m in, . m«it« --••-*-—*— dwwa* to provide these characteristics and dia ludn-oom* ^SS^^S^S^^^WgM&&&Z* w |aw*w« MW* MiMKiiamiM «>M .UM iwu wuw- eonunueus eastint lechnlaue as an aftesiurthM to the 

posftion typically includes mineral fillers indiesi^. y^^pt^^^^ZSi^^mZS 

d m carbonate or alwnfiumi Mfaydrate. It Is prtiftmd ^ ^ U A ft j ^ 160O490 bsued to BQIinxsefwanaae. bands wwriakka.lt is also preferred that «»wwyt as it BSI ^ doea, «r ^ aram rf the aaasa 

TSLK^^ S^To^^n^Sf'uSl^J^ • 

or machining after the sheet has been cast. product. To avoid the problem of wrinkling or tearing 

aingletlKnna^gorilwnnopJKtkreSnorandflure .tyt^tl*«^«tM»toand ^ • 

ofresi»suehttuiiutur»tedpolyester*andacry]IeKsin f^"*?> slippage tawttntbe $W * matrix and the 

precursors. Sueh resins require a catalyst and/or pro* • bdtofdKoonvevor.$pedfiedy.nillngiIeyteaehes« 

motersyjtentoiiutiatetl.eproca$offr«radlca1poly- P*oe«»ud^y^inat A rests on .layer of a film 

mrrirwkffi Typira?r«Ttn«Trer*"'aCTCTfrtdbyha^toga K wMcB ahnnka durim hcadni at the aame rate as the 

signirieant exothermic reaction during polymerbadon *>*& •«*; . Bfflingsley teaches Iha aaa of ofl or a 

andaaubstantialincKaseofdensityduringdiatprecess. abnilar liquid luttricanl between die fibn layer aad die 

Thus, a typical **mhturc«f 65% filler and 33% resin (a ' ct*

VBS'or Bt't

 *° • * approach, the film shrinks whh 

-matrU") shrinks during die polymerization procetf so the matrix and die thin fllm does not hang up oo tht 

diat dw cured solid composition IMS a density about 45 conveyor belts as it shrinks. 

S-8% higher than the Uquid matrix. This shrinkage Another conrinwwi cairin! awtroaebcanbe fennd b 

pmrtitt processing problems related to dw present US. Fax. Na *,9tfc09B Issued te Kato et aL Kato 

faventioa which ate discussed bdow. •' , ' teaches a dual belt system whieh n m dw force of a 

A vavi^bf prior madiodk have been uaed m achieve eeadbedtpawmeontrddwtaadeiideaofdw mania to -

synthetic sheet materials havfag a decorative patiem/50 distort or tear itself apart during tba polymerisation 

O&mid&iwlvasab* ^ -proen&Tlwmatrix fapais^'through aoonAnadapnoe 

the matrix is prepared by mixing the tesias whh tha o>Aoed by upper and bwerbtlt»whk*forwUw matrix 

filler and die desired decorarive partides or coloring » mdntafa a flat rectangular croaa sedion despite the 

n»teriah end widi a auwlard quantify of catalyst. The- presence of internal forces brought abort by toeaBxod 

amount of catalyst typically recommended in the prior 55 curing which wonld adietwiie eauae the matrix to puB 

art is ooe halfto two percent based ca die liquid resin apart, warp or bend. 

flactioo of dw matrix. Tbiamania fc thm poered or - Prom tbe foregoing it ean be seen that the prior art 

ptaped imoa large, caidng mold'and sealed iaitlM^ contmuous easting processes involve expensive and 

aoMFlhe mold is then subjected to snflldent heat to oomplicated amngenknts to eootrul dw curing of dw 

tegta deeompoaidon ef dw caulyst, which initiates CO polymeric materiaL Thieae prior art caadng mediods 

Kyaarizedon of dw resin. Beeanaa dw polymerisation alas pom quality problems, b corivendonalheltcatrihg ^ 

nexoi^ennic process. d» reaction contributes to tha equ^menttdje liquid matrix b fa thermal contact with 

heat of dw system, leading to Amber catalyst dacompo- • the bchs and may be heated by dw conduction of beal 

anion aad an increased rate of polymerisation. This . tlvough the bdtt which am enclosed in as environment 

follows the typical prior art approach whereby the M of heated fluid or gaa. Widi d& arrangement, the mold 

oonduedve er convective heat environment applied to or bah auriaee can cam* Initiation ef.a rapid acceleraidie matrix is warm enough to *1cick off" the polymeriza* .bg reaction before curing is complete, b extreme cases 

don reaction which then sustains itaelf by iu own heat diis can cause local boding, or at least, irregular cure 

•<w» 

7 
SfcWrBT:US fl'O fA'l'tNT SALtS 

_ _ P£_ 

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5,183,600 

3 4 

widi shrinkage stresses, cracking, ripple, craze layers, going polymerization occurs In a substanddly adiabatic 

etc. mamier. Optionally, additiood heat may be supplied to 

If the heating were to be done on a single supporting the mixture to iocreaae die reaction rale. According lo 

belt (without a top bell), the bottom of die matrix layer die present mveotion, h has been bund dwt dw matrix 

may polymerize before dw top, canting severe warp, 3 caa shrink uniformly without causing wrinkles on tbe 

concave upward. Also, excessive temperature differ* bottom sufftce and widiout developing problematic 

ences between die matrix center aad surface could stresses or deformities. 

cause flpw patterns to develop which reauh in objec * The present invention has the benefit of providing an 

tioaablea|>pearance of molding or streaks. The use of efficient uncomplicated method of continuous catting 

typicdbdt.'tysiems, panicularly together withconvee-10 diat avoids destructive intenwl and extend forces 

don heat, may resuh in die need to limh dw rate of which tend to produce distortion. It abo has the benefit 

beating, resulting Ina long heating time. This in turn of producing n cured homogeneous matrix with unimay require a higher matrix vbconty to reduce panicle form properties aad appearance. It also bas dw benefit 

setding. and longer equipment in the case of continuous of providing a sheet whieh shrinks uniformly througbeasting. Problems arise because, widi dw longer heating 15 out dw sheet materiaL dius avoiding warpage, wevitime, the viscosity of dw matrix udD be reduced for a ness, or odier rigns of ipegular shrinkage during cure 

longer period of time before it rapidly dimbs just prior even diough no externally applied pressure b provided, 

to gelling. This is illustrated in HG. 3. The lower vfc. Additiond advantages and benefits will be appareat to 

entity for an extended time will permit die mineral filler those skilled in dw an upon reading this tttsdotore. 

to settle and also any dense partides used for decorative 30 _ " nasruivnaN rat TH R nv AWMfic 

effctmaysettfeimdtioginaaontamogenomsheei BRIEF DESCRIPTION OF THE DRAWINGS 

bodi in physkd properties and in appearance at a cut FIO. I h a schematic flow diagram which depicts the 

process steps according to one embodiment of dw pres* 

SUMMARY OF THE INVENTION ^ n a Jisadiagmmadesldeelevatlondvfcwofime 

It it an object of dw present invention to provide an embodiment of an apparatus of the present fatvendoo. 

efficient and simple mediod and apparatus for cootinu- FIO. 3 is a diagram showing die rdarienship between 

ous casting of polymeric materials which shrink upon dw settling of the filler and the beating time of dw 

curing. It b an objea to provide a mediod which over- matrix prior to dw gelling fa • conventional heating 

comadwprebienuafpanicleKtdemeDt andsuriace 30 arrangement using conductive or convective heating.' 

distortion during the curing process. It is an object to FK3.4 is a diagram showing tbe improved retadooprovide a method which will prevent dw creation of ' ship between sealing ef dw filler end the shortened 

hternal stresses (and the assodated problems of warp, beating time made possible by the improved mediod tt 

cud aud craefcfag.) It fa a farther objective to provide a dw present invention. 

mediod which will avoid the tendency of the shrinking JS FIO. S is a graph Showing an embodiment of the 

matrix to detach itidfdue to shrinkage from the liquid heating sequence according to the present invention. 

^^SStt^^Snovdfc«ure.o f »*TAIL£D MNUffjON;OP THE RESECT 

the invention wUl be set forth in part in the description INVENTIO N 

which follows, and in pan will become apparent to 40 The process steps of the present invention are achethoae skilled in die art upon examination of the follow* maticdly illustrated in FIO. I. As shown ia FIG. L to 

ing or may be teamed by practice of the invention. The begin, dw matrix b prepared using a mixture of redo, 

objects and advantages ofthe invention may be realized filter and cpdonal mooomers, modifiers or ether mgre* 

and attained by means of the instrumentalities and com* dJents. The matrix fa unprepared for easting witii ti» 

Mnations particularly pointed out in the appended 45 aadhlonofpigmeaUindcatdysu.Tlwdecerative'Sheet 

claims. materid may be made of any polynwrixable material 

To achieve the foregoing and odier objectt and in - having flu, desired properties of heat assistance color 

accordance with the purpose of die present invention, stability, clarity, chamicd aad state resistance, sad 

du invention provides a method and apparatus for eon- edwrphydedpiopMtimsuilsbk'for'Cav'nwclrinnbilliy 

rinuous casting of a polymerizable materid which 50 and fabrication in dw polymerixed Hum. Tbe present 

shrinks upon curing. Aeeordlag to dw praent fovea- invention is particularly well suited lo materials which 

ti^E the mnpotitioa'Eia^an^u^E^usbig a controlled "shrink upon curing. Such materials are discjissrd fat 

emcmtfjftl ^ greater deufi below. 

piSfj|^ a web which b travd- '"„ - A oatdyst system typically consisting of oaa or mora 

n^lu a p^^ which b in a 55 caulyst groups b used. The oatdyst ahould be selected 

laj^statc.isallowedtcitn^ to permit gdling widiout significant shrinkage. The 

^lmti^'M:ti^'io'i»ooiB* level and sinooth by \, specific eatdyat selected and its concentratioa will de> 

dw||piCe^^ devioe could -' pend on tbe testa used. 

IK:UM&E&^ As explained more folly below, h has been found that, 

£ thenqnieidy Iwatirf at a point downstream of dw 40 by dw proper use of radio frequency eactgy, ths matrix 

..dcjj$t|!itt.^ may be partially jjoliymeriredquk^ and uniformly to 

•

:

ta&''iecikiaW''i-v-m\6 fteoncocy energy to a tempera* dw point cf cresting a solid rubbery materid suitable 

one did initiatespdyncnaarion. )t has been found in for further processing in accordance widi dw Invention 

accordance widi the present invention diat dw matrix before aa excessive amount of shrinkage ooeutt. Exceseanbe! awda te partially polyinerite quickly to a rub- 45 rive duiakage b that amount which, fa dw ease ef the 

berygdbeforeaignificamshrinkageeccura.Thereafter, given matrix, causes the matrix to form surftee wrindw mixture b mafaidned in subitaniisl thcrmd bolatioa kles, residual stresses, warp or. la extreme cases, to tear 

from iu auneunding environment. As a mult, the on- Itself apart. 

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• ^ 
ocm DIU J n u rrtiuvi JHLX.O • I-I<C-OQ > io-^o 

p.11 

A 0 1 OOI 1 U<iO<i • #-00/ QU 

5,183,600 

7 8 

between inlets 11 snd 19; ibe mstrix is blanketed along polymerize under adiabatic conditions at least to the 

hs length by a g o which approximates the temperature point when shrinkage U substantially complete, 

ofthe matrix. The matrix is thua maintained in subitan* In the embodiment of HO. 2, the gelled matrix sheet 

tial thermal isolation and polymerization proceeds in a • 42 ii carried on the web 4 and emerges from soaking 

substantially adiabatic manner. 5 chamber M. There, the web 4 is peeled from the bottom 

The apparatus or the present invention in one em* of the matrix sheet 43. Then traveling ssw 26, whose 

bodiment would end wiih soaking chamber 18. In the machine directional velocity is carefully synchronised 

embodiment of HO. 2. however, additional optional «*h theweb 4 velocity, makes a transverse cut through 

items are included as drmftwri bdow. the matrix 42. Thb separation by cutting physically 

la the region where the matrix aad web ate sepa* » W« w tbe delicate and dtfonnible -portionsif the 

nied, there h provided a traveling ssw 2& This « • gelled niuinx ftom shnhky stresses produced te the 

nngement fcr separating the sheet into individual downstream curing step. Sw* astejpJsjptanaTand 

pieces is optional. Alternate ways to control shrinkage other means CM be provided at> anrionedI ahwe. 

forces include the we of pinch rolls or by advancing IniteembodinitttofITO.2.^indiv^^ 

web4^«aughay>)ower>mtrth.nweb4or by other » nheett 44.«» de,»sned y Ae swfay y^^Tfc ; ^ds 

techniques known lo those skilled in the sit *• »° * *»"••» "WOrting tte gdled start 44. id* 

Dewnstreem ofthe traveling u w % there is pro- ^ces ^ the ^ttonslse^httO^^a i Bete 

vided a second section of conveyor platform 31 having lnogeIledSh^44optionanyma^liea«toasawn|l 

tm it weh 4'. Just beyond the second section of eon- ^^^SJ^^^SS^SJS ^ 

veyor platform 28, there is provided a second radio » ^^J^^i^»S^lSl^SS S 

wsveintcrfcrcncecbokeMuiJacentanoptioiuJsecODd TMS^* ^ lS32^KSL?STM ! 

heating chamber 31 Again, the heating ebaaber 32b JSS^?Jffi^£2KStee K 

ItlBmAtSX^^ enSSte5SSS&^5^ 

ehunb^Sathenkpn^mida.teteribenceehc^ 3Btf5Stt^JSw5S22 ^ 

3&A4iace«tothaexhteterieren«ch^Mbaseeond- ;£^JJS3££SL^ ^ 

a^^d^SSissuedwMcbisco * „ S^^T^E^ ^ 

structed and operates in essentially the same manner as ,b « the surToundina tas aod surwonlna membera in 

adi^ticsoatoa^bwll.lXwM.t^rfthesnc . a * chamber iTtf-eh^tteann ^ 

and soaking chamber 31, there is a cooling section. atsodated region of tl» cwmg intfrix sheet 44, tht 

^mtionofiheapparatoofttapre^iinventioo, ^trftdfeeiiveiy kt e thenndbolation fron Its envif iUuaia^bthemtejdin^tfHO. * 

follows. Xdcaen coated paper sheets 4 is pulled from and webs 4 and 4'have a low beat capacity and low 

toll % and threaded through the equipment line to the tfcennal conductivity. These wrihknt provide n wimotorized rewind ro0 2L As the web 4 advances, Just fa^. temperature profile la aD .direction* uniform 

prior to the entrance to the casting section, the edges of «ross-sectiond shrinkage and mntaaxatioa of wans, 

the web 4 arc folded sharply upright to form a moving ^ y^»intw and wifr^ftmrd strptus 

trough with vertical edges. •yju pieaeot invention relies, in part, upon certain 

A Iiquidnwtrix42which has been heated toatemper> reUrionthips 

aiurest which the hairiifc ofthe caulyst is such that the eniei of polymrrfc w h matirrialt snd thrir raHyi*' 

matrix wQI not polymerize In lhe pipe leading to the eystems discovered to be advantageous te the continu* 

canting head 8 and which has been passed through,a 45 p ^ t*wfag of polymeric imrtt riab **»ch shrink duHhg 

static mixer is pumped at a constant flow rate through polymerisation. Various materials were ned in lhe 

the casting head 8 onto the moving web 4. The relation* WQ^ reponed and the Wmiffr of the present tevm* 

sUp among the matrix flow rate, ihe web velodty and tion sre characterized as follows but art not mesnt tons 

the web width establishes'the average thickness of the limited by the following description. Thoee eklDed te 

Bqold matrix 42. Tbe web 4 advances a sufficient length JO ibean will recognize tba various dasao of polymerie 

to allow tbe liquid nutrixC to flew to a levdsurfiice: materials and eoanposites which can be used fa accer** 

Thev ^ 4 then euers the heating cavity 12 threugh the daue with flie present feverition. 

faterierence choke 10. Ia that hating cavity U, the , 

iquld matrix is heated quickly and uniformly ung Folyealcr Beam 

radio frequency energy to a temperature selected lo 55 An unsaturated polyester carting resin is prepared by 

activate the catalyst group and 10 cause polymeriratioo a condensation resctiaaofo^ydrfcaleQbQl and dibasic 

to a gd state withoat cawing a strongly exothermic adds. The viscous reaction producta are tim dissolved 

reaction and without cansing execuive shrinkage. fa vinyl or acrylic mooomeia such as styrena, vinyl 

Web4ibcnadvancesthrougheshfaterferettecheke toluene or methyl methacrylate (MMA). Tbe rates 

IS aad through adiabatic aoakbg chamber 18 whieh is so used contained about 30% styrene monomer, about 

mctmained at the same temperature as the aasociated • MSft MMA monomer and have a viaoadqr of dbout 

section of the matrix throughout its length as described 500 to 2^00 cp at 20 degrees C 

above, fa this manner, the combinstion of starting resin. These reams typically contain n steal! amount of ia* 

estslyat, heating temperature and rate of advance of dw hibitor, sueh as hydroquteone te prevent premature 

web caa be adjusted to provide a firm rubbery gd exh* 4S gelling during storage. They dio typically contain antiing ihe soaking chamber 18 which gd has not yet under* oxidanu and UV absorbera to hdp control aglnf and 

gone excess ve shrinkage. In one embodiment, the ma* UV degradation ofthe cured puts which cause yellow* 

trix remains in aoakiag chamber 18 long enough to lag. embrittlement and other physical deterioration. 

IV 
P.12 

5LINI CT-U5 ftU TAILINI 5ALH5 • I-U---0 • iO-^O laiaa'iiuzo^.ftiu/ou 

5,183,600 

9 10 

dd re^pplSsan'd ihS'exact composition is p!£ "HLPOINT 90" (Witeo Cheraicd Co.) 

prietary to the supplier. A wide variety cf resins ean be Mediyl ethyl ketone peroxide (MEKP) is n catdyst 

used according to die present invention. However, typiedlyuaedtoiainawftemdicd'reacriaos'iapdyes*' 

those found particularly well suited to be adapted for *. teirresins. When it isused donate the resin; it begins to 

usete the present inventionihavethe following charac- toomiwie at a toly high taapernture above 200» P. 

teristics: (I) They can be pdymerized to a thermoset- * Wenuarfwimasmdl^BiDOinrtofn^inphiher^ 

ti««ateby«fteradicdreKtle»iri^faycatdys* -^^^!^^SS}S^SmS ^ 

and (Z) tbe density of the cured teste is substantially Thus, polyester iwfaconwnteg about 1- ^ of MEKP, 

lttgberthantheIiquidretJn.Untheretbshrinfa<faring

 , 0

 ^J*"*!*^0^ 

^Accord^tepublishedmdtne^mddendS ^^^^^1^..%^! ^ 

the infilled mte typicaUy ean shrink up to about 15% ^S^i^J^SSSt 50 *

,ed ^m,BB n 

dur^i^vmerizatiooofr^eateranduptoaboul20% *•"««" te dimethyl p&tbtiate. 

te the ease of unfilled acrylic teste. The mixtures of w "U5F*245" (Witco Chemical Co.) 

rah and fDIer used (about JS * resin and 63%minerd *Mte*«h*l.2J Us OethjMexnnoyl peroxy hex* 

^

t,HWTT^4md%^Lf^I^ 4bhDqS^^t£«dSo»^ M*"^*^/W~Tte*ir.te8lat o «torobata*mlVF.Iib^S«aWbaSv e cocunlvnropically.Le, the same amount m each diree* n\wt» ' 

tJon, a volume shrinkage'of 7% would be caused by M 

linear shrinkage of 241%.- Lower filler rates wiO'have • "PERCADOX ItT (AKZO Cbemieds Inc.) 

correspondingly higher shrinkage. DH4-t-butyl<cycIobexyl)»peroxy dtearbonatc is a 

fa tbe cue of a minerd-nOcd resin matrix in which powder that dissolves in. styrene pionoimr, aad decomthe ADer has a substantid beat capacity, much ofthe poses rapidly in thamrinat about 110* P. Jt haa been 

fine energy change during polymerizatioB resuhs fa an 33 .£ ^ WprodueeagdtimBOf4-3 aunutesnl 130" P.* 

facreased temperature of the fiUer as wafl as the resin. jad dius caa be used ss aa alternative to ths cerabtea* 

The redns most preferably adapted for the present fa* tion of MEKP and cobdtnaphthenato.lt Is supplied as 

venrknshOMM be cnrable in a reasonably short period aa 100% active ingredient. 

during whidi the find cure b conducted in an essan* m~*<***nar*» «*•* /*«*<•;•. #•». I„I. « .% 

tidlydieimdlyisdattdcnvironnmtwitfaow TRIGONOX C (AXZO Cbemieds Inc.) 

ad heat of reaction causing enough temperature rise to t>buty]perexkfabenzoattbali«iMthatdecooipoecs 

cause thermd degradation of the polymer. - rapidly in polyester at about 250* P. It Is supplied as an 100% active ingredient 

EXAMPLES 

OSumiirtrnjnini 

Mttfcy) wnhaaytau MH W 

A1HPb«*r 

Pte»m» Fantefct 

I U 

41 

414 

309 

Aluminum Trihydrate (ATH) 

Aluminum Trihydrate(ATH)b a naturally oocunfag 35 

minerd derived froa processing of bauxite ore used te Aspects of the present favendon nre shown by the 

the manufacture of dununummetaL Its'inolecular fbr* following examples for puiposes of fllustratioo. .These 

nuIsisAbQi3H20.SBdhihspure,refinedstste,itbaa example* and cmhodinwMx are nw meant lo limit the 

almost white to yellowish granular soUd. fa a finely favendon in any way. Those skilled fa the art win reegroundfomv ATH has been widely used as a filler fa *° Qgnize diat changes, additions and modifications may be 

•|a»sticsloimpfOVerirerwisUnce.IibmoHU«fttlwhen irade,aU within the. spirit and scope of tbe invention, 

ground to an average partide size below shout 30 mt- EXAMPLE 1 

croas, but not too much bdow about 5 microns. The 

low practied limit of particle size b set by the viscosity A matrix rnlxture b prepared eoatppaed oft 

ofthe resin * ATH matrix. Thai: b, as the ATH particle .•».. 

dsc:'"6 reduced, its higher surface area resulo te te* 

creased visoosity ofthe matrix, making it km suitable te 

the present invention. At above shout 20-50000 cp, it 

becomes very difficult to process, pump and pour the -_ 

nurrixVVjth a deiired mixture of^Slfc ATH, 35% min, * 

thb vbcosity range occurs with ATH parddedse of The matrix b pumped at a rate of44#/Wn through 

about 1CV-20 microns depending on die processing con* a modified heat exchanger to preheat the matrix to 125* 

dittoes and the .particular brand of ATH. The.Ugh F. Once preheated, caldyat and pigment are added and 

Heeded Hmit ef particle size would be determined by «.

 1*iu* by use of a static miser assembly. The eompod* 

its settling rate andthusb dependent on the coneentra* tion of the catdyst sdutionjs.asfoBo*s: . 

tknfo the serin and the gd time ofthe matrix. For 45% ____________ — — -'^_______ _ 

ATH 33% i«rin mixtures, hb prefer^ te die ftfeseat rmAatfc . is* 

invention that particle size not exceed about 30 nderons. Tn>anC is*. 

The preferred filler ratios are from about 40% 10 40 tymmt4mtmm io» 

about 15%, and die more preierred rsrio b from about 

50% re 65%. tlw lower rede, of<»unc.befeg the most Tlw catalyrt sdutlon b a~cterad at a rate of 023 

difficult relative to heat of reaction. Tbe lower pre* (Mate Into die matrix stream. Tins provides ncoooau* 

/erred redo of ATH b appYoximatdy ths minimum tradoa of 0\2% Percadox I6S, 02% Trigonox C based 

oeneanradon that stiU provides good fire-hazard char*. *4S on the liquid portion ofthe matrix mixture. Tha matrix 

acicristlcs suitable for building applications, but lower • b then-dispensed oa to the web traveling at three feet 

ratioscould be used iffirereriuanceisofno concern, or per minute wiih s widdi of 38" to produce a aomiad 

if other means are wed tp provide fire resistance. 0.300" sheet. The matrix trsyds a suffleieni distance to 
P.13 

SENT BY:US PTO PATENT SALES ; 7-12-96 : 15:29 ; - 19199410234:#41/50 

5,183,600 

11 12 

give approximately 2 minutes leveling time prior to aomind 0.500" sheet. The liquid b then heated to initientering an RFduunber where about 13 KW b applied ate the polymerization and b dlowed to exotherm to a 

to lhe matrix, thb yidds a temperature of approxi*. temperature of approximately 230* F. to 240* F. During 

maidy 150* F. to 160* F. which starts die polymerize* the exotherm period the sheet it held in ibe adiabatic 

don. ln approximately 6 minutes the material has gelled s section'io bolate h from the outride environment. Tbe 

to a nibbersute and the paper b removed. The continu- • paper b then removed and tbe sheet beut to be deposous sheet b cut to the desired lengdi. At dus pant the ited omo die r*^iif bdt. The sheet b then pessed 

matrix has increased in temperature due to the exother* through die second RF cavity snd heated to apptoximie polymerization reaction to approximately 210* F. tnatdy 250' F. After passing through the soaking area 

but has not yet had sigmficant change to density. 10 & sheet b dlowed to cool to sootn temperature. The 

The wt matrix sheets are deposited onto s second d^ett are observed to be free ofwarp and other defcets. 

5 * S^uf^J? 6 J?"TM *•*••* • *? c m d * f Upon physicd tesdng it is found that the residud ity. 

d

^

,

^!S^^ d^I?»" ^ taeb^herUwthdofeznnxpteLItteiwftiiedtlit 

will have been heated to approximately 265*F. It b t^t-a^usotionwIiemfafa^lmaeetheBseofn 

dien pssed tea second soaking clumber where,I* is X,E^J!ns^^ ^ 

^per«ureinciearatoappre^dy^F..»(rF. 3 e ^ e S

3

^

<

SSSSw " 

doe to the heat ofreaetion. The fully cured sheet b then *"?._ r"^-„T.L^T£^7r_T7Lj.,_ t _•*«*«. 

cooled evenly and slowly to room tempenture. The ^iHSiSSS ^ IKSlTS S 

be exhaustive or to lfaut the invention to tlie precbe 

EXAMPLE 2 fonn disclosed. Obviously, many modifications aad 

A sheet U prepared according to example 1 with tha ^tion s are possible fa Hght of the above teaching, 

exception diat die cutting step b omitted. That b. once j5 2^^? M ^L5^ e M ^ fff^T^T!!!!^ 

the idcere paper web has been removed, the continuous chosen and described in order to best explain the princtgelled sheet bredepotited onto a continuous bdt The P1

** of the invention and its prettied apptiearion to 

bdt b constructed wthst ft dot* itt restrict sBpnage thsr*y enable others skilled fa the sit to best utilize tha 

between the sheet snd itself. The speed of thb bdt pref bveadoo te various embodiments and whh various 

errablyn independently controllable so (hat it can run n modifications ss nre suited to the particular use oontcnv 

slighdy slower dun the initld web. Ia dda manner plated, 

ahrfafcagc can be accounted for. What b claimed is: 

The eondnuous matrix sheet b dien passed through LAmethodofooottenoudycssttegapolyxKrizahle 

the second RF cavity and soaking section. Once the .Squid materid which contains a particulate filler and 

aheet exitt the oven it b then cut to the desired lengdi u which shrinks during polymerization to produce a sheet 

and allowed to cooL The sheets are Observed to have no substantially free of ware*, eonsbting essentially oft 

rignificamififrereneeinappeafanceorphysicdpropcfw (a) depadting a controlled amount of a Uquid mixture 

ties than those of example 1. containing said materid on a web having aa up~ 

pyiwp i -p « sticsin direction snd a downstream direction and 

40 moving st a predetermined speed to provide a 

A dieetb prepared according to example I with the moving mixture *of contained thickness; 

exception that a second RF cavity b not used. Once the (b) heating add mixture substantially uattbrady 

idled materid has been cut and redeperited onto the throughout Hs cross section by radio frequency 

second bdt it bellowed to rise in temperature under iu energy downstream of said deporitteg step ot least 

own heat of reaction, during whieh dme the sheet b 4} ten temperature »v**yfr«»» to labiate polymerize* 

TnvtKng through the second adiabatic soaking are&andlitm ; ' 

reaches a-maximum temperature of approxfmatdy 2S0* ^ providing CftndWtmt whifh fabHste ahrfakage 

F. The duets exit the oven and are cooled to room forces that occur ta said mixture further down* 

temperature. There b ao significant difference fa np* p^m ft^ ^ y t^t, , fop, traasstdasfan appearance or physicd propenies when compared to M stream: 

sheeta of example I. (d)matotabteg add botaed mixture foretime da-reafter in substantid Ihennd bdattea and free of 

substantid conStrdning forces such that pelymeri-

- astion and Amber shrinkage ocean te a sabstan* 

35 daily adiabatic meaner; 

whereby a sheet b provided free of eobatantid warp. 

2. The method sccording to dafan 3 wherein add 

radio frequency energy bfadw range of about 4to 2450 

megahartx. 

31A mediod of continuously ousting a nolymcrisable 

Bquld materid which contains a paideulate liller and 

which shrinks during polymerization to-produce n sheet 

substandaOy free of warp, eonsbting esscadaDy oft 

00 depositing a controlled amount of a liquid mixture 

45 containing add materid on n web having aa up* 

ao that the Percadox concentration b 04% based on stream direction and a downstream direction and 

EXAMPLE 4 

e matrix b prepared composed oft 

thuwttcd Vttfmtt Ken 

ATM SMI 

and b pumped st 20 #/mtn and mixed widi a catalyst 

mtptnf ffft** fning* 

SkRaduISS 

liyttM 

IS« 

SS* 

liquid. The matrix b then dispersed onto a web moving moving at a predetermined epeed to provide 

two feet per minute with a width of 30" to produce a moving mixture of controlled thickness;-

n