p.1 

OAR Box 1413 

Prepped by Ollie Stewart 

Document Number: 

53) 11-1-53 

Docket Number: 

A-94-52 

Printed 7/9/2008 3:11:22 PM Sheet 53 of 114 
P.2 

United States Patent m 

Rodgers 

US005372493A 

[li] Patent Number: 

[45] Date of Patent: 

. 5,372,493 

Dec 13,1994 

[54] CONTINUOUS CASTING APPARATUS 

USING TWO MOVING BELTS 

[76] Inventor: • Gary C. Rodgers, 647 Laurentian 

Avenue, North Bay, Ontario, P1B 

7T8, Canada 

[21] AppLNo.: 62^24 

[22] Filed: May 13,1993 

[51] Int CL< •••••••••*»•*_•••••••*••••••«•*••••••••••*.•••••• 

B29 C 43/22 

[52] VS. O. . 425/188; 425/193; 

425/223; 425/224; 425/371; 425/378.1; 

425/388; 100/151; 100/152 

[58] Field of Search 425/223,224, 371, 372, 

425/378.1,388,85,193,188, DIG . 60* 100/151, 

152,154, 153 

[56] References Cited 

U.S. PATENT DOCUMENTS 

4.406,850 

4,420,359 

4,541,889 

4,714,015 

4,826,560 

4,839,125 

5,042,372 

5,185,115 

5,244,618 

9/1983 

12/1983 

9/1985 

12/1987 

5/1989 

6/1989 

8/1991 

2/1993 

5/1993 

Mlk 

Goldsworthy . 

Held..-

Stabler. 

Held... 

Ida 

BielfddtetaL 

Thole ...... . 

Kemereretal. 

-.. 264/171 

— 100/151 

„. 156/583.5 

,.-.. 100/154 

— 156/498 

264/216 

425/371 

— 425/371 

— 425/371 

Primary Examiner—Khanh Nguyen 

Attorney, Agent, or Firm-—David P. Gordon 

[57] ABSTRACT 

2,866,730 12/1958 

3,193,888 7/1965 

3,376,371 4/1968 

3,422,178 1/1969 

3,487,143 12/1969 

3,620,158 11/1971 

3,622,393 11/1971 

3,708,566 1/1973 

3,745,846 7/1973 

3.764.247 10/1973 

3,792^53 2/1974 

3,904,336 9/1975 

4,004,870 1/1977 

4,008.024 2/1977 

4,311,550 1/1982 

4,334.468 6/1982 

Potchcn et aL -_. 

Rochester 

Opel et aL .....—.. 

Junker et aL .___. 

Bergwall ________— 

TorellietaL — 

Sherwood -~~-.. 

Junker etaL —. . 

Birc_t___e___i 

OanettetaL — 

Ahrwefler __._. 

AxeretaL ..__ . 

Guttmger et aL — 

YokotaetaL — 

Kerttnla 

Guttiager et aL _ 

154/100 

425/371 

. 264/216 

264/216 

264/216 

100/154 

136/148 

264/171 

425/223 

425/371 

_ 425/371 

425/371 

425/224 

425/371 

425/371 

100/93 RP 

A apparatus for continuously casting a liquid thermoset 

resin or composition in which a liquid thermoset resin 

or composition is fed into a space defined between a pair 

of moving endless belts arranged such that the lower 

run ofthe upper belt is disposed above the upper run of 

the lower belt; the adjacent runs ofthe belts are moved 

concurrently with each other at substantially the same 

speed and a first fluid container is provided above the 

upper belt with its lower surface in contact widi the 

lower mn ofthe upper belt A second fluid container is 

provided below the lower belt with its upper surface in 

contact with the upper run of the lower belt The fluid 

in the first fluid container is maintained at a first desired 

temperature and the fluid in the second fluid container 

is maintained at a second desired temperature. The 

lower mn ofthe upper belt is maintained in contact with 

the lower surface of the first fluid container whereby 

the lower run of the upper belt is held up widiout any 

substantial sag. 

8 Claims, 3 Drawing Sheete_ 
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U.S. Patent Dec 13,1994 Sheet 1 of 3 5,372,49 3 

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U.S. Patent Dec 13,1994 Sheet 2 of 3 5,372,493 

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U.S. Patent Dec 13,1994 Sheet 3 of 3 5,372,493 

12. 28 

70 74 

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5,372,493 

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examples cited in this patent it appears to produce the 

CONTINUOUS CASTING APPARATUS USING product at a rate of from 0.114 to 0.216 meters per 

TWO MOVING BELTS minute. The longer system described in U.S. Pat No. 

4,046.850 gives examples of speeds of 0.217 to 0.624 

FIELD OF THE INVENTION 5 meters per minute. The longest system described in U.S. 

This invention relates to a process and apparatus for **• No. 3,376,371 gives abdt speed of 0.914 meters per 

continuously casting a liquid diermoset resm or compo- minute, 

sition, such as a thermoset plastic, into a fnishH shape. 1° the above-mentioned prior systems it will be seen 

The term "resin" will be understood to mean a liquid that an appropriate length of time is required for the 

polymer without any filler added to it The term "com-

 10

 adequate transfer of heat fiom the heat source to the 

position" will be understood to mean a blend of liquid product being formed or produced to effect polymeripolymer and some type of filler anywhere fiom fibre- zation as desired. The methods used to achieve this have 

glass to clays or any organic or inorganic material that been either running a short system slowly or providing 

could be added for whatever reason. The described a longer more complicated system running at a faster 

process and apparatus may be used to produce either

 15

 speed. This increases the critical dimensions of the 

unfilled product made from resin or a product that is forming area of the system. Furthermore the product 

made fiom a composition of inorganic or organic fil- being formed has to reach sufficient strength before it 

ler(s) and resin. can tolerate the removal fiom the surfaces which define 

The unsaturated cross-linking monomers used in the die product shape, due to the nature of the belts recompositions of this invention are the compounds con- 2° quired for these systems and their poor natural release 

ventionally used for dus purpose, for example, styrene; properties. This also dictates the speed and/or lengdi of 

alpha-methyl styrene; 2^-dimethyl styrene; 2,5- the belt forming section. 

dimethyl styrene; 2,4-dimediyl styrene; alpha-chloro The use ofthe cavity formed between die metal belts, 

styrene; alpha-ethyl styrene; methyl propyl styren**; ^ whatever means, as a heat exchanger is believed to 

p-ethyl styrene; b*rom<wytrene; dicbloro-styrene; iso- » ^ m ^gggj^ metho d whe o time is a fector. This 

propenyl toluene; vinyl naphthalenes; tte «>, m- and inefficiency becomes magnified the thicker the crossp-chlor^jand brom^styrenes- esters of »!?•*-««%- section of the part that is being formed. The cavity 

1

^ , (f

b

Si, a , ^,!^ l l !!^ y l "Sf^jS S formedbythebdtstodefinetheproductbeingfonned 

""f t ^ffilS ^ iS^,"" 3* ? **?? « i$ best sited for that purpose alone anTdrformity 

^^^^J^^^r^^ . tli^ f should be avoidSTL as possible. EffidS 

methacrylate; ethyl methacrylate; methyl ethacrylate;

 o f

 ^odwA to "»

 heate d surfece' 

acrylonitrile; methacrylonitrile; vinyl esters such as SUMMARY OF THE INVENTION 

vinyl acetate vinyl propionate; vinyl butyrate; vinyl 35 _..__ . 

laurat-nvM stearati aidvhiyl chloro-acetate; vinyl According to one aspect of the present invention 

ethers such as vinyl methvl ether; vinyl isobutyl ether; there is provided a process for continuously casting a 

vinyl 2-chloro ethyl ether and vinyl stearjrl ether; vinyl &?** thermoset resm or cjmpoaton which comprases 

ketones such as a vinyl methyl ketone; vinyl heptyi the steps of feeding said hqmd thermoset composition 

ketone and methyl isopropenyi ketone; olefins such as 40

 iaSo a space defined between a pair of moving endless 

isobutylene; vinylidene halides such as vinylidene chlo- ^t * arranged such that the lower run ofthe upper belt 

ride and vinylidene fluoride; N-vinyl compounds such

 is

 disposed above the upper run of die lower belt; causas N-vinylpyrrolc; N-vinyl carbazole; N-vinyl indole i°S the runs to move concurrently widi each other at 

and N-vinyl succinimide; acrylamide, ethacrylamide, substantially the same speed; providing a first fluid conN-methylolacrylamide; allyl compounds such as diallyl 45 tainer

 abov e

 said upper belt with its lower surface in 

phthalate; allyl alcohol; allyl acetate; allyl methacrylate; contact with the lower run of said upper belt; providing 

diallyl carbonate; allyl lactate; diallyl moltmntt- diaDyi a second fluid container below said lower bdt with its 

g\prm»tfa.AiMy]»f.ipi,tta.^intlyisebactte;di__Hyt<»ifn_. - upper-snrfi-ce-in-contact- with the upper run of said 

conate; die diallyl ester of muconic acid; diallyl hacon- lower bdt; maintaining the fluid in said first fluid conate; diallyl chlorophthalate; triallyl citrate trfaiiyi cyan- 50 tamer at a first desired temperature; maintaining the 

urate; traflyl phosphate trimethallyl phosphate and SsM in said second fluid container at a second desired 

tetraallyl silicate. temperature; and mamtaining the lower run of said 

upper bdt in contact with die lower surface of said first 

BACKGROUND OF THE INVENTION fi__ container. 

Previously proposed continuous cast systems used in 55 According to another aspect of the invention there is 

resin systems diat polymerize have a section of the provided an apparatus for continuously casting a liquid 

former that introduces heat to the product, and a se» thermoset resin or composition which comprises a pair 

tion of the former th&t carries out the post cure process. of moving endless belts defining a space therebetween 

This generaUy makes for a long system that requires a for said Uquid thermoset composition and arranged such 

large amount of critical control area. In U.S. Pat N a 60 diat die lower ran of die tipper bdt is disposed above 

3,376^71 (issued Apr. 2,1968-Opd et al) the apparatus the upper run of the lower bdt; said runs, in use, being 

is 50.3 meters long and in U.S. Pat No. 4,046,850 (issued caused to move concurrently with each other at subSep. 6, 1977-Kato et al) the apparatus is 15 meters in stantiaDy the same speed; a first fluid container above 

length. Other systems that are shorter operate at such a said upper bdt with its lower surface in contact with die 

slow speed diat dieir commercial use in the production 65 lower run of said upper bdt; a second fluid container 

of this type of product is questionable. An example is bdow said lower bdt with its upper surface in contact 

U.S. Pat No. 3,422,178 (issued Jan. 14, 1969-Junker et with the upper run of said lower bdt; means for maind) which has a length of 3.65 meters and referring to the taining the fluid in said first fluid container at a desired 

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5,372,493 

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temperature; means for maintaining the fluid in said circulates heated water througih platen contamer units 

second fluid container at a second desired temperature; 12 and 18 to create a temperature which is substantially 

and means for maintaining the lower run of said upper equal to die temperature of the pre-heated composition 

bdt in contact with die lower surface of said first fluid 10 as it enters the space between the bdts. Thus very 

container. 5 little heat is lost into the platen. 

**«*»*- mr.«TMrr»T»«., « „ —,m -_„ . nrn.,_-,« As shown in FIG. 1, the bdts 2 and 4 are inclined at 

BRIEF DESCRIPTION OF THE DRAWINGS anangleof about 15 degrees to the horizontd and the 

Embodiments of the present invention will now be resin composition is hdd in a batch mixing holding tank 

described, by way of example, with reference to the unit 40 and is fed to the dispenser unit 8 by a metering 

accompanying drawings, in which: 10 pump unit 42 which measures the resin composition and 

FIG. 1 is a diagrammatic representation of apparatus the catalyst for adding later, 

according to one embodiment ofthe present invention, After emerging from between the upper and lower 

FIG. 2 shows part of the apparatus of FIG. 1 in bdts 2 and 4 at die point of egress 44, die product 10 

greater detail, and travels along a horizontal moving endless conveyer bdt 

FIG. 3 is a cross-sectional view of part ofthe appara- 15 46 having been transformed into a formed sheet 48. 

tus according to a second embodiment of die invention. A saw unit 50 is provided above the bdt 46 to cut the 

The same reference numerals are applied to like parts formed sheet 48 into desired lengths, 

in all the figures. The power for driving the upper and lower bdts 2 

nBcronmnu /-_» TOTS _,_.__,! imm .

 an(* * is obtained firom a synchronous drive unit 52. A 

DESCRIPTION OF THEFREFERRED M foithe[ synchronou s drfye unit 54 is also provided for 

EMBODIMENTS ^ 1<Jwer ^44^, 1 for ^ horizontal conveyor bdt 46. 

Referring to the figures, a pair of moving endless In FIG. 2, a head pulley 56 and a tail pulley 58 for the 

bdts 2 and 4 defines a space 6 between them. The bdts upper bdt 2 are shown in greater detaiL A bdttensioner 

may, for example, be fabric bdts. A dispenser unit 8 unh 60 is provided in association with the tail pulley 58. 

(FIG. 2) feeds a quantity of liquid thermoset resin or 25 A corresponding head pulley 62 and tail pulley 64 with 

composition 10 at a controlled rate on to the upper run a tenaoner unit 66 are provided for the lower bdt 4. 

the lower bdt 4 ahead of the space 6 between die two The saw unh 50 indudes a highly polished chrome 

bdts 2 and 4. sted rod or tube on which one side of a saw bridge is 

A platen unh 12 is provided above the lower run of supported and along which it can travel The saw is 

the upper bdt 2 and is constructed as a hollow vessd 30 mounted on a traverse threaded screw mechanism and a 

having a flat external surface towards the bdt 2 and hydraulic drive motor is provided for the saw. In its rest 

fluid inlet and oudet ports 14 and 16. A corresponding position die saw is raised up and adjustable feet are 

platen unh 18 is provided below the upper run of the provided to pennit sdection of an appropriate cutting 

lower bdt 4 and is constructed as a hollow vessd hav- depth dependent on die thickness of the formed sheet 

ing a flat external surface towards the bdt 4 and fluid 35 48. The saw or slitter is subject to friction advancement 

inlet and oudet ports 20 and 22. along with sheet 48 as the slitter moves transversdy of 

As can be seen more dearly in FIGS. 2 and 3 a vac- the sheet 

uum plenum unh 24 is located above the platen unit 12 A cantilever arrangement is provided' for the upper 

and is connected to grooves 26 in said flat external platen unit 12 and, referring to FIG. 3 it will be seen to 

surface of platen unit 12 by way of pipes or tubes 28 40 indude a lower support member 68, an upper support 

passing through the platen unit 12. The grooves 26 may member 70 with an intermediate lift cylinder 72. Gauge 

be herringbone or chevron-shaped and holes drilled clamps 74 and 76 are also shown in FIG. 3 as wdl as 

through the platen 12 interconnect die tubes and the gauge blocks 78 and 80. The cantilever arrangement 

respective groove or grooves may be oriented in such a facilitates removal and/or replacement of the bdts and 

way as to pull wrinkles out to the edge of die bdt 45 in the raised position the upper platen unit 12 is hdd in 

The embodiment shown in FIG. 3 is similar to that in position by means of a hook arrangement. To change a 

FIGS. 1 and 2 except die platen units 12 and 18 are not bdt associated cylinders are retracted, die bdt then 

constructed as large tanks or containers for water, or becomes loose and can be slid off. A different size can 

other heating fluid, but are constructed from two layers be put on if one wants to change the dimensions—for 

of aluminum plate for the platen with channels 30 50 example, to produce a wider or a thinner product 

within the metal to form a cavity for die water to circu- In operation, the process is started by the loading of 

late therein. The channels 30 are formed by grooving the batch mixing tank unh 40 with up to 1125 kgs of 

out one ofthe plates, the plates being wdded along their resin, and adding tinters as per batching instructions, 

edges. However, distortion may be difficult to avoid so, Tmter and resin are blended together whfle a vacuum is 

alternatively, an O-ring seal could be used all around 55 drawn on the mixing tank 40. ATH filler is metered into 

the perimeter with damping bolts for the plates. the tank through a flush ball valve mounted on the 

The lower bdt 4 is constructed with integrel side bottom of the tank directed into the mixing head or 

dams 32. These may be polyurethane preformed rectan- blades. 1000 kg bags of filler are hung from a frame 

gular strips bonded to part of die bdt 4 and they act as mounted on digital read-out scales to monitor flow rate 

guide strips whidi help to define die width and height 60 and shut-off point Vacuum should be minimnin of 20" 

ofthe product which is nonnally a formed sheet They and preferred to be 25". Feed rate ofthe filler should be 

travd around with bdt 4. Alternativdy, the strips could 20-25 kgs/minute. After all filler is loaded, vacuum 

be fed in sepaxatdy instead of being bonded to the bdt should climb to 27" and mixing continue for 20-30 

In FIG. 1 a partid vacuum/exhauster unit 34 is pro- minutes. Temperature should be monitored at this stage, 

vided to maintain the vacuum or suction pressure on the 65 120 to 125 degrees F. is expected, 

lower run of the upper bdt 2 to hold it in contact with The mix at this point will have a viscosity of 

the platen unit 12 and prevent sag ofthe bdt A hot 14-16000 cps. A metering pump in the tank unit 40 will 

water tank 36 with an associated circulation pump 38 draw the matrix from die bottom of the tank and pump 

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it through a hot water heat exchanger which will fur- Catalyzation produces an exothermic heat gain. Enther raise the temperature to 150-160 degrees F. Probes dosing the production and curing sections wfll utilize 

will be installed at several points on the material section die heat to mnintam a controlled temperature environof the exchanger to monitor the correct heat gradient ment Heat in die curing section should be hdd around 

gain. A controller will vary the flow rate of the water as 5 180 degrees F. The air in this area will stratify, allowing 

required to meet predetermined values. The matrix wiU the product to cool as h reaches the lower curing secbe drculated bade into die batch tank 40 until the dis- tion levds. Supplementary heat will be required to 

charge temperature is seen to be stable at required vd- bring die environment temperature up on production 

ues. At this point, die discharge from the exchanger will line start up. Exotherm can raise the temperature ofthe 

be connected to a static mixer. Catdyst line will be 10 product to 250 degrees F. and will probably be able to 

connected and production line can start supply most or all ofthe heat after start up. If required, 

Graphs and flow charts will have been produced cooling may be added to lower levels of the curing 

giving the resin and catdyst start set points as expected section. 

to be required depending on size of sheet being pro- As described above, pre-heating takes place ina sepadu<*«d The pump has infoitdy and independendy vari- 15 ratdy designed heat exchanger to heat the product 

able stroke lengths as wdl as an infinitdy variable drive prior to introduction into the forming cavity. The adspeed. Stroke lengths will be adjusted manually. Drive vantages of this appear to be that the heated product has 

speed of the pistons are inter-connected with controls lower viscosity and will flow and fill die cavity better, 

regulating the variable drive speed of die fonning sec- Since heating of the product has already been carried 

tion. A slowing up or an increase in speed ofthe form- 20 out h is ready to polymerize as soon as it is shaped in 

ing bdts wiU automatically adjust the flow of matrix by the cavity thus permitting a shorter overall length of die 

making the required speed changes to the pump. system; introduction of the catdyst at the point of disViscosity of the matrix is now about 7-8000 cps and charge into the forming cavhy will produce a substanflows quite fredy. This ensures a good fill of the in- tially stress free product in cross-section since the temclined cavity being filled. Due to die raised temperature 25 perature of die product is uniform throughout the resinand resin design, gelation begins in 50-55 seconds after ous mixture. In the above-mentioned prior art systems, 

catalyzation. At 60-65 seconds, the shape of the matrix the resinous mixture is pre-catdyzed and heated in the 

is permanent The discharge of the static mixer must be fonning section. The product in contact with the heated 

within a few feet of the former opening. Producing J" surfaces will begin polymerization first the process and 

production wifl mean 3.5-4 seconds ofproduction in die 30 the related shrinkage not being consistent and even 

static mixer. Another 3 seconds wiB be used up in die through the cross-section. The greater the cross-section 

line fiom the end oftiie static mixer to the actual desired dimension, the greater the problem which may arise, 

discharge point at the feed end of the former. Both A further advantage ofthe instant described system 

fonning platens are temperatare controUed to ensure appears to be that die design of die heating for die 

tbat there wfll not be any heat loss fiom the heated 35 forming section area can be simplified to maintain a 

matrix. The ensures a more uniform cure through the process temperature rather than provide the process 

cross section of the matrix and a more predictable gd temperature, 

time through the duration of die production run. In some prior systems the length of time for the prodAt the design speed of 6'per minute, the matrix wiU uct to attain a desired temperature can result in fiUers of 

be dimenaond formed and stable in me first 5' of die 40 greater specific gravity settling out of the resin. The 

forming section. By the two minute mark, and point of instant described system reduces this problem due to the 

discharge, the materid is quite flexible bnt dimension- continud movement of the product through the heat 

ally stable and permanent It also releases very readily exchanger and equipment blending the catdyst into the 

from the Teflon covered forming bdts or other self- resinous system which keeps the partides in suspension, 

lubricating surfaces. Although die bdts in the forming 45 Also, the heated product is ready to polymerize as soon 

section are moving, they are motiodess relative to each as the catdyst is introduced providing a gdating of the 

other and die product being cast within die cavity de- resinous mixture in less than 1 meter into the fonning 

fined by the bdts. BasicaUy, we have one continuously seaion and thus aHowing 1 ^ time for any s^arating of 

moving mold that comes together at one end to define the particles from the min. It wfll be appreciated that 

the shape and opens at die odier end to release the 50 die heated less viscous mixture can provide the advanproduct tage of higher fiUer loading and better wetting out of 

As the product exits the fonning section, a IS degree the partides in die product providing a better bond 

flexing is required for the product to be taken on the between die partides and resm. 

horizontal conveyor 46 (FIG. 1). This section indudes In the system described with reference to FIGS. 1,2 

the cut-off saw or slitter 50. The consistency of fhe 55 and 3 a forming length of 3 meters has been demonproduct at this point is somewhat like cheddar cheese strated at belt speeds from 1 to 2.4 meters per minute, 

with a litde more flexural and body strength. Depend- In the above description the liquid thermoset resin 

ing on the actud physicd properties of the product composition 10 is fed direcdy on to the lower bdt 4 to 

being produced, a circular slitting blade wfll cut deady provide the formed sheet 48. The described apparatus is 

without any "saw dust". If required, a very thin, fine 60 equaUy applicable for use in applying a resin coating or 

toothed or abrasive blade could be instaUed. The prod- a resin composition to a pre-formed rigid or semi-rigid 

uct is quite free from any stickiness at this point board. This would be placed on the lower bdt 4 before 

As the product moves dong, it activates a sensor the application of the liquid composition 10 (FIG. 2) 

located at a point that wfll start the slitter unit 50, cut- and would then travd between the two bdts 2 and 4 

ting the product to specified length. After the sUtter has 65 where the liquid wfll bond to the board and a more 

made its cut a roller rotating above wfll lower and uniform thickness can normally be obtained when cornaccelerate the product giving it suffident vdodty to pared to one previous system where sanding machines, 

load it onto the loading tilt table ofthe curing section. have to be used to produce a uniform thickness after 

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forming a second composition sheet separatdy and 

bonding it to the board. The bdts 2 and 4 in FIG. 1 

would, of course, be more horizontal and in-line with 

die bdt 46. 

The product win be produced continuously and tachometers are used throughout to sense the drive speed 

and will, for example, supply the composition to die 

former section whereby when one gets the required 

flow speed that is working wdl at that speed, it wfll be 

"locked in". If the product is a litde too soft an adjustment can be made to slow that section down and allow 

a little more curing time. The dispensing wiU automaticaUy adjust Also, to speed up production an adjustment 

can be made. The plates give shape definition for die is 

product and not the bdts. Previously, sagging of the 

lower run of the upper bdt diminished or distorted the 

size of die cavity between the bdts. 

In FIG. 1 die water in platen units 12 and 18 is maintained at approximatdy the same temperature by a common hot water tank 36. However, if different temperatures are required then the platen units 12 and 18 can be 

connected to separate hot water tanks and not interconnected. It wfll also be understood that a cooling 

fluid could, dternativdy, be used if desired. 

The continuous cast system according to one constructed embodiment was designed for continuous 

product production from pre-mixed liquid state to individud sheets induding: 

1. infinitdy adjustable production rate with sdf regulating product dispensing rate; 

2. automatic sheet cutting to length on die fly; 

3. automatic self regulating materid handling from 

sheet cutting, dirough curing station, and onto skids at 35 

curing station discharge point; 

4. sheet width and sheet thickness changed with expected down time of 15 to 20 minutes; 

5. sheet length adjustable to 12,10, and 8 foot lengths 

from main control console sdector switch; 40 

6. production rate of 12.5 to 18 sq. ft per minute, 

depending on product width; 

7. three standard thicknesses; 

20 

25 

30 

L Apparatus for continuously casting a Uquid thermoset resin or composition to produce a formed sheet 

which comprises: 

0) an upper moving endless bdt and a lower moving 

endless bdt defining a space therebetween for sdd 

Uquid thermoset resin or composition and each bdt 

having and a lower run arranged such that the 

lower run of the upper bdt is disposed above the 

upper run of the lower belt; 

00 said runs, in use, being caused to move concurrently with each other at substantiaUy the same 

speed; 

(ui) a first fluid container having a lower surface 

above said lower run of sdd upper bdt with its 

lower surface constituting a platen in contact with 

die lower nm of said upper bdt said first fluid 

container having an inlet and an oudet port; 

Qv) a second fluid container having an upper surface 

below sdd upper run of sdd lower bdt with its 

upper surface constituting a platen in contact with 

the upper run of sdd lower bdt said second fluid 

container having an inlet and an oudet port; 

(v) a hot liquid tank to supply pre-heated Uquid to the 

inlet port of one of said fluid contamers and receive 

return Uquid from the oudet port of the odier of 

said fluid containers, the oudet port of said one 

fluid container being connected to the inlet port of 

sdd other fluid container; 

(vi) grooves formed in the externd surface of the 

platen of said first fluid container towards said 

lower run of sdd upper bdt; and 

(vii) a vacuum plenum unit connected to each of said 

grooves to maintain a partid vacuum or suction 

pressure in sdd grooves to hold up said lower run 

of sdd upper bdt widiout any substantid sag. 

2. Apparatus according to claim 1 wherein sdd vacuum plenum umt is located above sdd first fluid container and is connected to sdd grooves by tubular members passing through sdd first fluid container. 

3. Apparatus according to claim 1 wherein said first 

and second containers each comprise twp layers of 

metal plate connected together with fluid channels 

therewithin. 

8 4. Apparatus according to claim 1 wherein integral . produce sohd colours, "granite" look, and easily 

adaptable to "marble" look product;

 45 side daaa "* provided on sdd lower bdt to define the 

9. machine easily modified to produce custom lengdis width and hdght of Mid formed sheet 

other than industry standards; 5. Apparatus according to clannlmdudmg a cantilei^iiufft^-ts~emm^i^m--mmm v« ar^emrat for ^^ ^ 

lLp^uction line operated by one operator and one 50 %g £££,?* ^ ^ "" ^

 uA/a rCplaCe" 

6. Apparatus according to claim 1 wherein said pair 

of endless bdts is at an acute angle to the horizontal and 

materid handling; 

11 PLC control; 

13. close dimensiond tolerances; and 

14. manufactured to "hazardous locations" standards. 

It wfll be readily apparent to a person skilled in the 55 

art that a number of variations and modifications can be 

made without departing from the true spirit of die invention which wfll now be pointed out in the appended 

claims. 

I claim: 60 

induding a further moving endless bdt for recdving 

the sheet exiting from sdd space on hs upper run. 

7. Apparatus according to claim 6 wherein sdd acute 

angle is approximatdy 15 degrees. 

8. Apparatus according to claim 6 induding a saw 

unit above the upper run of sdd farther endless bdt to 

cut sdd formed sheet 

• * * • • 

65 

9.