CA1221518A - Moving laminar flow of plasticized materials divergently towards orifice - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE
Method and apparatus for extruding laminated plastic products. One process for extruding multiple thermoplastic resins comprises supplying separate streams of thermoplastic resins into an extrusion apparatus and causing the streams to combine therein in a flowing manner to form an interface between said streams. The combined streams are then caused to flow laminarly without any mixing across the interface between the thermoplastic resin streams so as to maintain the physical integrity of each stream in said combined stream. The overall cross-sectional geometric configuration of the combined stream is altered within a forming die thereby providing a thermo-plastic resin extrudate exiting said die, which has a coexten-sive, integral, and uniform configuration of said thermoplastic resins in said extrudate.

Description

~2Z~Si8 This invention relates to novel apparatus and methodsfor the production of novel laminated products and more specifically relates to the production of laminated products wherein two or more overlying and coextensive fluid films are formed with laminar flow and, after forming of the laminar streams, are extruded through a common extrusion die orifice, the laminated sheet undergoing a lateral extension with a substantially zero coefficient of friction at the interfaces of the laminated products. By laminar flow is meant the flow of two or more adjacent streams without turbulence so there is no mixing of the materials of the streams. The present invention particularly recognizes that laminarly flowing adjacent streams can undergo a lateral extension without causing normally expected turbulence due to adherence between the stream surfaces.
There is a widespread need for laminated materials, in flat sheets or tubes in many varied applications.
By way of example, the seal range of presently used low density high melt index overwrap plastic film is relatively critical. In accordance with the invention, one side of the film can have a surface laminated thereon of high density, low melt index film, while the other side of the film can be of relatively stiff material. As another example, two separate streams could be laminated to insure a pinhole-free product. Again, materials of different comp-ositions and different colors could be internally laminated to produce a desired structure or form some desired pattern.
Many other novel products which can be formed in accordance with the invention will be described hereinafter.
Heretofore, compound extrusions have been accomplished with dissimilar and/or pigmented polymers.

- 122~518 Such dies are complex in design, and usually contain one or more separate passages to separate adjacent ox concentric orifices and the molten polymers are joined, sealed or adhered together, in the area beyond the extrusion die lips.
Other ar~angements are known to the art whereby laminated products are formed within an extrusion die. In these arrangements, however, it is not recognized that the product can be laterally extended before or after leaving the die while maintaining the integrity of the laminations.
By lateral extension, is meant the extension of the film in a direction perpendicular to the direction of the flow path. Thus, in a circular extrusion, the diameter of the flow channel within the die may constantly increase to the discharge orifice while still maintaining an integral laminar relationship among the second materials.
As an important feature of the present invention, a novel die structure and method is provided wherein similar and dissimilar thermoplastics, some of which may be pigmented, are joined prior to discharge from a common ex-trusion orifice, and are extended laterally and/or longitudinally after discharge, and while still in a molten condition, to form a laminated film product. By a film product, is meant one whose thickness is less than 10 mils, as contrasted to a sheet product whose thickness is greate~ than 10 mils.
In accordance with the invention, these film products could be as thin as 0. 1 mils (0. 0001"), e. g. 0. 5 mils (0. 0005").

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--- lZ2~5~8 More particularly, sinse all 'ayer thic~nesses are independently controllable during ~nd ~fter extrusion of the thermoplastic material, and compatibility of the relative materials comprisin,~ e~ch independent film i5 unaffected, each layer can represent any percentage of the whole film section with ~ny single layer being as thin as o.oooo66 inches in thickness. 1~minated products a~ thi3 th~ckness are not known to have been produced hereto~ore with methods available to the prior art.
More particularly, the conventional methods where- ~ _ in preformed finished films are overlayed and ~oined could not deal with films o~ such thin dnd ~ragile gauge dimensions.
Thus, though it is known that two ~ilms can be lndivldually cast and then laminated together either by adhesives, or otherwise, in such a method a certain minimum stiffness, and thus thickness, is required for the handling of the individual films. Since the individudl layers o~
film are not handled separately when using the process of the invention, it now becomes possible to laninate ~ilm layers of a thinness previously unusable.
In accordance with the invention, dissimilar, similar and plgmented therrnopl~stics can be introduced under pressure into the same extrusion die and be made to laminate over, under and inbetween a base extrudate if desired. Thls al30 applie3 ~or dissimilar polymers, i.e., polyethylene, polypropylene and vinyls and virtually any combinatlons of extrudable thermoplastic materlal. Control of this process ls very easily accompllshed since each di~ferent thermoplastic Il Il.
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1~ ~L2~518 ~`! material is supplied i`rom one or more single respective extruders and the v~rious molten streams are joined or Il associated within a common extruder die b~ l~minar flow ¦i within the die.
This might be accomplished through use of two extruders feeding a sin~le die. The lamination will occur no less than 4 11 inside the die and a good seal between jl the two layers is assured. The Joined streams then flow minarly toward the outlet or di~cnarge orifice without mlxing~ ¦
The die may be constructed with an internal core d~ viding a ~irst ~eed ~hannel into two streams. ~ second ¦¦ feed channel ln the core then supplies a central layer for the product to be formed. Control o~ amount dnd g~uge of the various streams may be obtained by appropriate location and dimensioning of the core. As previously stated, the ¦ streams would ~oin somewhere within the die so the lamination ¦ is formed under pressure.
The extrusion die of the invention may also be of the type having a tubular orlfice for the formatlon of an extruded tube. Thls type die will have an internal mandrel forming a circular discharge orifice with the die body, with expansion of the tube occurring within the die, if desired followed by further expansion, by vlrtue.
¦ A wholly unexpected feature of this inventlon is ¦ that the laminated films have, durlng extension of the fllm, ¦ very little frictlon at their interfaces so that the two films, which are coextensive, will extend lndependently o~
one another and uniformly, notwithstanding that they may have di~ferent mechanical properties.

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12Z~S18 By way of example, ln the case of a flat die arrangement, the laminated stream flows through a relatively small internal die channel, to be discharged by way of an extended orifice, whereby the film must extend laterally oYer a considerable distance within the die. Because of the un-expected low friction forces between the ldmin~te interface~, each film was able to extend independently and uniformly without any mixlng of the films or inter~ilm friction. Similarly, in the case of a circular die, the laminates have a constant radial thickness due to the low interfacial friction, and no undue gauge variation was found in the films 80 produced.
Whether the die is circular or flat, additional channels may be added to introduce new flow paths so that at least four films can be laminated into a single sheet.
Moreover, a dle rotàting etructure could be used with a circular die, with the outer laminate being a stripe ~hich form~ a helical lamina on the body of the film.
It will be further shown that the novel die and techniques o~ the invention can be utilized for applicatlon to injection or blow molding systems, whereby to produce symmetrical products for the formation of lined elements such as bottles.
The novel apparatus and method of the invention has been used for the formation of a great number of plastic film products, many of which are novel in themselves.
Examples of these novel products will be provided in detail hereinafter.

~2X~S~8 Accordingly, and within a broad aspect the present invention provides extrusion apparatus for extruding laminated plastic products; said extrusion apparatus including an extrusion die defining a flow path for fluid products and having a discharge orifice comprising, a first conduit passageway having one end adapted to be connected to a first extruder, a second conduit passageway having one end adapted to be connected to a second extruder; said first and second conduit passageways communicating with said flow path; whereby materials flowing from said first and second conduit passageways are laminarly joined under pressure before extrusion through said discharge orifice; said flow path having a divergent portion toward said discharge orifice, whereby said laminarly joined extruded materials are laterally extended prior to discharge from said discharge orifice.
In accordance with another broad aspect of the present invention there is provided an extrusion apparatus for extruding laminated plastic products including an extrus-ion die defining a flow path for fluid products and having a discharge orifice comprising, an annular plate member having a passageway therethrough defining a portion of said flow path having an outlet, a flow diverter in said passageway adapted to divide said passageway into at least two separate and spaced flow channels, at least one conduit passageway defined in said diverter to open toward said plate passage-way outlet in substantial parallel flow relation with said spaced flow channels, said passageway being adapted to be connected to a first extruder by means extending through said annular plate said conduit passageway in said diverter being adapted to be connected to a second extruder whereby materials flowing from each of said passageways are laminarly `~ -'A-.~.

122~S18 joined under pressure before extrusion through said discharge orifice, said flow path having a divergent portion toward said discharge orifice whereby said laminarly joined extruded materials are laterally extended prior to discharge from said discharge orifice.
Additionally and according to a further broad aspect of the present invention there is provided a method for form-ing a laminated body which comprises the steps of joining the flow of a first molten material into laminar flow with at least one additional molten material, the materials being joined under pressure, and thereafter moving said joined materials with laminar flow in a divergent flow path toward an orifice opening and extruding said joined materials through said opening.
According to a still further broad aspect of the present invention there is provided a process for extruding multiple thermoplastic resins comprising supplying separate streams of thermoplastic resins into an extrusion apparatus and causing the streams to combine therein in a flowing manner to form an interface between said streams; causing the com-bined streams to flow laminarly without any mixing across the interface between the thermoplastic resin streamsso as to maintain the physical integrity of each stream in said combined stream; altering the overall cross-sectional geometric configuration of the combined stream within a form-ing die thereby providing a thermoplastic resin extrudate exiting said die, having a coextensive, integral, and uniform configuration of said thermoplastic resins in said extrudate.

, -5B-~L22~8 The inventlon will readily become apparent upon reading the following description of the accompanying drawings, in which: ¦
Figure 1 shows a view in vertical section of an extrusion die ad~pted to join four laminates ahead of ~
common circular die orifice, wherein the extruder sources of the four streams are shown schematically.
Figure 2 shows a top plan view of the die of Figure 1 on a reduced scale.
Flgure 3 shows a front elevation view of a novel flat die constructed in accordance with the present invention.
Figure 4 shows a cross-sectional view of Figure 3 taken across the lines 4 - 4 in Figure 3.
Figure 5 shows a perspective view of the novel die of Figures 3 and 4.
Figure 5a shows a bottom view of the novel diverter orifice plate of Figures 3 and 4.
Figure 5b shows a cross-sectional view of the plate body of Flgure 5a.
Flgure 5c shows a top plan view of the diverter orifice of Figure 5a.
Figure 5d shows a side plan view of the diverter orifice of Figure 5c.

122~i18 Figure Se shows a cross-sectional view of Figure 5c across lines 5e - 5e in Figure 5c.
Figure 6 shows a modified diverter orifice plate wherein the man feed is through the central slot in the diverter orifice.
Figure 6a shows a cross-sectional view of Figure 6 taken across lines 6a - 6a in Figure 6.
Figure 7 illustrates apparatus using the concepts of the present invention for blow molding techniques.
Figure 8 illustrates the type of die shown in Fig-ures 1 and 2 whereina die rotating structure is provided.
Figure 9 shows a novel laminated film produced in accordance with the invention.
Figure lO illustrates a fire-resistant laminated film having a vinyl outer laminate.
Figure 11 illustrates a top view of a film having a laminated tear strip thereon.
Figure 12 is a cross-sectional view of Figure ll taken along lines 12 - 12 in Figure 11.
Figure 13 illustrates in perspective view a further embodiment for a film having a tear strip therein.
Figure 14 shows a top view of the web shown in Figure 13.
Figure 15 shows a high strength film having stiff outer layers on a relatively soft and inexpensive inner layer.
Figure 16 illustrates in perspective the manner in which an electrical capacitor can be produced in accord-ance with the techniques of the present invention.
Figure 17 illustrates in perspective an electrical resistor formed in accordance with the techniques of the invention.

Il ~2~S~8 Figure 18 is a slde elevational view of a multi-conductor i ~able constructed ln accordance with the invention.
ll Figure 19 is a cross-sectional view of Figure 18 across ¦¦ the lines 19 - 19 in Figure 18.
Figure 20 is an elevational view illustrating an electrical reactor constructed in accordance with the lnvention.
~ igure 21 is a cross-sectional view of the reactor of ¦ Figure 20 across the lines 21 - 21 in Figure 20.
Figure 22 shows a bag having inwardly curved panel sections to bias the bag open.
Figure 23 i9 a cross-section of Figure 22 across llnes 23 - 23 of Figure 22.
~ ferrlng now to the drawings, ln Figures 1 and 2 there is illu~trated an extrusion die having a central mandrel 10 withln an outer die body 11 adJust~bly connected to a die base 12 by suitable bolts connected from ~lange 13 in outer body 11 to base 12 in the usual manner. An inner ring 14 and outer ring 15 are suitablY connected to mandrel 10 and outer body 11 respectively to define a circular die orifice 16. In this ~tructure, various sizes Or palrs of rings 14 and 15 can be used to obtain various diameters for orifice 16.
Orifice 16 communicates with annular channel 17, as sho~n, where channel 17 is connected to a first extruder schematically shown as extruder 30 Which ~upports the die and forces a molten product under pressure through annular web 18 and into channel 17. ~ , Up to this point, the die descrlbed iR of a type well known to the art and operates to discharge an appropriately lnflated tube of an appropriate thermoplastic material through orifice 16.

~22~S18 In accordance with the invention, a conduit 20 passes through body 11 and communicates with a suitable annular channel or passage 21, opening into the channel 17 through an annular orifice 21a in the outer wall of channel 17. The conduit 20 is connected to a second extruder or second source of plastic material, schematically shown as extruder 22, which material may be similar or dissimilar to the first material forced through web 18. Because of the laminar flow of molten material within channel 17 toward orifice 16, the material from passage 21 coats the outside of the material coming through web 18, whereby the two streams are laminately joined under pressure prior to discharge from orifice 16. As the molten materials are ultimately passed through orifice 16, the resultant product is formed of two laminae which have the desired characteristics in their respect-ive opposite surface portions. Moreover, the extruded tube may be distended to increase its diameter, without rupture of either lamina when the tube is inflated since, until the tube laminae are set by cooling, they have been found to have substantially zero friction at their interface.
Further, in accordance with the invention, a tube having any desired number of laminar plies can be formed.
Thus, in Figure 1, two additional molten products may be injected into the die through channels 31 and 32 respectively which are connected respectively to extruders schematically shown as extruders 33 and 34. Channels 31 and 32 communicate with annular orifices 35 and 36 respectively which, in turn, communicate with the channel 17 through the respective inner and outer wall surfaces thereof.
During operation of the die of Figures 1 and 2, a gas under pressure is applied to the interior of the plastic tube, formed by the extrusion from die orifice 16, by way of the channel 37 in mandrel 10. Any su.itable means can be used ~2~ 8 `tl- ~o introduce t~lis ga~ into channel 37. With extruders 30 and ¦ 22 in operation, the material from extruder 22 and channel 21 will be deposited on the outer surface of the molten material i from extruder 30 passing upwardly tArough channel 17. The laminated product will then be forced through orifice 16 with ,I the resulting tube being formed of the two similar or dissimilar i' layers intimately bonded to one another.
i! When extruder 34 is also in operation, it will deposit a 11 further layer of material on the layered material from extruder ¦l 22. The resultant tube leaving orifice 16 will then be comprised ¦ of a "3-ply" material with each layer having its own particular characteristics.
When extruder 33 is also in operation, it will deposit a further~ and inner layer of material on the interlOr of the body of thermoplastic material moving up channel 17. Thus, a four-ply film will be forced through orifice 16 having an outer layer of the mflterlal from extruder 34, a second layer of material from extruder 22, a third layer of materlal from extru-der 30, and an innermost layer of material from extruder 33.
Referrlng now to the ~tructure as shown in Figures 3, 4 and 5, a sheet extruding die ls illustrated, lncluding dlverter means wherebv to accomplish the novel, laminar flow method of extrusion contemplated by the present invention. In this structureJ the numeral 50 designates a generally conventional ~lat die body havlng a neck portion 51. A pa~sage~ay 51a is ¦ formed in the neck portion, and communicates with an angularly extended or divergent passageway 50a in the body 50. The passage .
way 50a, in turn, opens into a channel 50b extending for sub-stantially the total width of the dle, being closed at the oute~
ends, but having a coextensive radial outlet such as deslgnated ¦I by the numeral 50c.

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il, , lZ21518 Also, in generally conventional fashion, the die body is adapted to receive a pair of die lips 52 and 53, mounted on the die body 50 in parallel spaced relation to provide an intermediate passageway 54 in communication with the passageway 50c and opening through an orifice 55 for discharge of a sheeted film product. Means, not shown, are conventionally provided for attachment of the lips 52 and 53 to the die body 50, and also for adjustment of the lips to provide for guage control in the film web discharged from th~ orifice 55.
In the conventional structure, the neck portion 51 would be bolted directly to an extruder nozzle such as designed by the numeral 56 in Figures 3, 4 and 5, the noz-zle 56 being secured in turn at the outlet of the extruder barrel 57. In the modified apparatus shown, however, a diverter plate 62 is interposed between the nozzle 56 and neck portion 51.
The diverter plate, as shown, is adapted to provide a matched fit intermediate the nozzle 56 and the neck 51.
The plate 62 may be considered as having obverse and reverse surfaces 62a and 62b. The plate itself generally conforms to the shape of the neck 51 and nozzle 56 and is secured thereto as by means of bolts. A shouldered passageway 63, opening through the obverse and reverse surfaces of the plate 62, also is adapted to match at least the passage 51a.
The numerals 63a and 63b designed the passageway shoulders.
In the passageway 63 is a diverter element 64.
This element is shaped to divide the passageway into two parts providing two flow channels therein which are spaced apart by the body of the element. This element is formed ,~ -11-~221S18 from a solid block having a length and width such as to permit its press fitted insertion into the passageway 63, and a depth such as to permit its engagement against the passageway shoulders fi3a and 63b, with the opposite ed~e portion surface lying in the same plane as the obverse surface 62a of the plate 62. As shown, intermediate the ends of the block, it is machined on both sides in an area substantially corresponding to the distance between the shouldered portions of the plate passageway to produce a channeled portion on each side wherein the surface is adapted to cooperate with the wall of the passageway 63 to form the flow channels 63c and 63d. The outer edge of the block is also machined to provide a wedge-shaped contour which serves to split a stream of molten or plasticized material into two streams which will flow through channels 63c and 63d. Likewise, the inner edge of the block is machined substantially in the manner shown to achieve streamlined flow.

In addition, the block is drilled to provide an internal passageway 65 having an orifice outlet 66 opening radially in parallel relation to the respective surfaces of the channeled portions. The drilled passageway has an inlet disposed so as to coincide with a corresponding passageway 67 drilled through ~he side edge of the plate 62, and centered on a line parallel to the side walls of passageway 63. The passageway 67 is internally threaded at its outer end to receive a supply conduit 68, adapted for connection to a second extruder such as the extruder 71 of Figure 3, Figures 5a, 5b, 5c, 5d and 5e illustrate the nature and structural features of the diverter plate 62 and element 64 in greater detail.

~2ZlS~8 In operation, and referring particularly to Figures 3 and 4, a first thermoplastic material i5 forced from ex-truder 57 into nozzle 56. The diverter element 64 in plate 62 causes this material to divide and flow in channels 63c and 63d. At the same time, a second extruder such as schematically illustrated extruder 71 forces a second molten material into channel 65 in diverter element 64 and through discharge orifice 66. Accordingly, the product flowing below diverter 65 will be a laminate of a central material determined by extruder 71 and outer surfaces determined by extruder 57. This flows to the die orifice 55 in a laminar manner so that there is no mixing of the various layers whereby the discharged product will be a laminated film wherein the various layers may have guage dimensions too thin to be produced by presently known techniques.
Moreover, and as an unexpected feature of the invention, the laminated structure easily spreads throughout the length of the die passageways when the film goes from the narrow width to wide width within the die. This occurs because of the unexpectedly low or near zero frictional inter-face between adjacent layers.
It will be noted that additional plies can be introduced by providing additional discharge orifices in the diverter 64, or in the walls forming passageway 51a.
Moreover, the relative thicknesses of the various laminae could be varied by using different thicknesses for channels 63c and 63d between the plate 62 and diverter element 64.
Moreover, an important feature of the novel structure is that a standard line can be quickly modified for lamination operaton by the simple addition of a suitable plate 62.

~221S~8 A modified type of diverter plate is illustrated in Figures 6 and 6a l~herein film is produced with the central lamina being formed from the main extruder 60 of Figures 3 and 4, while the coating laminae are produced from the extruder 71 of Figure 3.
The diverter plate as shown in Figures 6 and 6a differs from the plate 62 of Figures 3, 4 and 5 in that it is, as shown in Figure 6a, formed in two parts, female and male, respectively designated by the numerals 72 and 73. The part 72 is similar to the plate element 62 of the preceding figures and has obverse and reverse surfaces 72a and 72b, and a passageway 74 defined in the plate and opening through said surfaces. This passageway is disposed intermediate the side edges of the plate along a diameter thereof. In effect, this passageway is an elongated slot extending radially from the plate center to an equal distance in each direction therefrom. The ends of the passageway preferably are rounded and machined to provide a mating surface adapted to match with a similar mating sur-face on male part 73, as later set forth.
The plate 72 is drilled to provide a bore 75 ex-tended through the edge of the plate intermediate the obverse and reverse surfaces and on a iine parallel with the side walls of passageway. The bore 75 stops short of one end of the passageway 74. A bore 76 is also drilled ~hrough the obverse surface on a center line intersecting the center line of the bore 75, to open into the latter.
The obverse surface is routed to form bifurcate grooved portions 77 and 78 starting from the opening of bore 76 and extending into parallel open sided relation to the passageway 74 intermediate the ends thereof. Similar and matching grooves are formed in the male part 73, as later described.

122~18 The male part 73 is of substantially the same dimension and conformation as the part 72, and has obverse and reverse surfaces 73a and 73b. On the reverse surface of this part 73 is an elongated boss 80 originally having the exact conformation of the passageway 74, the end parts being rounded and polished for mating relationship with the end parts of the passageway or slot 74. The side walls of the boss, however are routed and machined to provide wide flat groove portions 81 and 82. The bottom faces of the respective grooves, when disposed, as particularly shown in Figure 6, in opposition to the side walls of the passage way 74 cooperate therewith to define a pair of channels 74a and 74b.
The reverse surface of the plate part 73 is also routed to form grooves 83 and 84 adapted for matched relation to the grooves 77 and 78. These grooves 83 and 84 at the base of the boss 80, are formed to open laterally into the grooves 81 and 82 in the boss. A slotted portion 85 is formed in the boss to open therethrough from the obverse surface of 20 the plate part 80. This portion 85 parallels the grooves 81 and 82, and is substantially coextensive therewith for the length of the groove portions 81 and 82.
In use, the plate parts 71 and 73 are assembled by insertion of the boss 80 into the passageway or slot 74, with the groove portions 83 and 84 matched to the grooves 77 and 78 respectively, whereby they cooperate to form a bifurcate passageway communicating with the bore 76. The two plate parts may then be bolted together to form a united assembly.

-122~5~
This assembly may be employed in substitution for the plate 62 of Figures 3 to 5 inclusive. As will be evident, when so employed, the feed from the extruder 57 will be de-livered through the longitudinal slot 85 in the boss 80, while the feed from the extruder 71 will be delivered by way of the bores 75 and 76 and the bifurcate passageway to the channels 74a and 74b. Thus, whereas when using the plate 62 and its diverter element 64, the feed from extruder 57 is divided to coat both sides by the stream supplied from 19 extruder 71, when using the plate assembly of Figures 6 and 6a, the coating action is reversed, the feed from extruder 57 being coated on both sides by the stream supplied by extruder 71.
While the invention has been described heretofore in connection with the drawing of thin film, it will be apparent that the novel laminating method and apparatus are equally applicable to molding techniques in general. By way of example, Figure 7 illustrates the manner in which the invention would apply to a blow mold system for the pro-duction of symmetric articles such as bottles which havean interior lining which is particularly impervious to the material which is to be contained by the bottle, while the exterior surface is of a relatively inPxpensive material.
If desired, a third outer layer of easily printable material could be added, should the main outer layer not be of such quality.
Referring now to Figure 7, I have schematically 1llustrated a well known type of blow molding system which includes mold halves 100 and 101 whlch define a symmetric bottle, and are connected to and supported by suitable rams 102 and 103 respectively. The upper portion of the mold receives a suitable knife 104 which is operated by mechanism 105 in the usual manner.

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~z2~la The die used in the blow mold system is schemati-cally illustrated as die 106 which is connected to an ex-truder 107 through a suitable adaptor 108. The die 106 is such that it will extrude a hollow cylindrical tube of material 109 through a suitable die orifice under pressure from extruder 107.
In accordance with the invention, an annular discharge orifice 110 is added to the die 106, and is con-nected to a second extruder, schematically illustrated as extruder 111, through the conduit 112. The material of extruder 111 will operate to place an external coating of material characterized by material from extruder 111 on the layer 109. Thus, the tube shown below die 106 has an inner layer 109 of material from extruder 107 and an outer layer 113 of material from extruder 111. The material 109 will be of some material desired as the bottle lining material and can be selected to be particularly impervious to the material contents for which the bottle is designed. The outer material 113 is then relieved of the function of being resistant to the contents of the bottle, and so can be selected for qualities of strength and cost. If desired, an additional layer could be laminated outside of layer 113 which is particularly capable of being printed, should the material 113 not be so capable.
In operation, the tube is discharged from the die and concentrically with an air blowing tube 115 which extends through the die 106 and adaptor 108. The tube 115, as is usual for such arrangements, may be withdrawn from the die.
Thus, when the tube extruded from die 106 is long enough, the rams 102 and 103 cause mold halves 100 and 101 to close.

122~S18 Air pressure is then applied to cause the tube to expand into the mold to conform to the mold shape and the bottom of the tube is sheared off. Thereafter, the air tube 115 is withdrawn, and knife 104 is operated by its operating mechanism 105 to shear the top of the mold. Thereafter, the mold is opened and the symmetric article molded is removed and a new cycle is begun.
It will be apparent that the same techniques described in Figure 7 would be equally applicable to an injection molding system whereby symmetric articles can be injection-molded with some predetermined liner material and some other predetermined body material.
As previously indicated, it is sometimes desirable to laminate at least one stripe into the body of the material being extruded. It is apparent that in the embodiment of Figures 3, 4 and 5, this type of striping can be achieved by simply constricting the width of the discharge orifice 66 in the adaptor member, whereby the flow of the striping material is reduced to an amount less than required to coat the entire surface of the flow streams through channels 63a and 63b.
In the case of the circular die arrangement of the type described in Figures 1 and 2; it is also possible to introduce a stripe into the tube being extruded, and it is also possible to cause the tube to rotate, whereby the stripe appears to spiral about the finished product.
A suitable rotating structure, along with another embodiment of means for injecting a coating film, is par~
ticularly illustrated in cross-section in Figure 8. In Figure 8, a portion of the die is essentially similar to that described in Figures 1 and 2 so that similar parts have been given similar identifying numerals.

~;~21S1~3 The die structure as shown in Figure 8 is a rotatable die adapted for employment of the laminar flow extrusion technique according to the present invention.
In the drawings, the numeral 140 designates an extruder nozzle having a flanged outlet 140a. Mounted on this outlet, and fixed thereto is a pivot plate 141. This plate provides

2 substantially concentric boss 142 extended therefrom, the plate and boss defining a conduit passage way adapted for communication with the interior of nozzle 140.
On the outer end an annular die bearing cap 143, is threaded on the boss 142, and pinned thereto. The cap 143 provides an annular flange 143a, adapted for engagement by two annular ball bearing raceway assemblies 144 and 145.
The remainder of the die structure is supported on the bear-ing 144 for rotation about the cap 143.
The die assembly itself includes two mated die support plates 146 and 147 respectively. These are annular members adapted to define a continuation of the flow passage-way through the pivot plate 141. The plate 146 is supported on the cap 143 and the bearing 144 substantially in the manner illustrated, and is adapted for mounting on a peri-pheral gear or sprocket plate 148, through which the plate 146 and the balance of the die assembly may be driven for rotation about the cap 143.
The plate 147 corresponds to the die base 12 of Figure 1, but is modified to provide a conduit passageway 151 forming part of an air supply conduit system.
An annular thrust cap member 149, adapted for threaded engagement with the plate element 146, and bearing against the bearing 145, serves to draw the plate 146 into sealed rotationally movable relation to the pivot cap 143.

5~8 jj The balance of the die structure, beyond the plate 147, also corresponds to t~le structure of Figure 1, including the die bodj 11, a mandrel 10, ~nnular orifice members 14 and 15 and an ori~ice 16~ continuous with ~n annular ch~nnel or passageway 17. The m~ndrel 10 provides a central bore 37 which is closed at its inner end~ lnd connected, by a p~ssage J
not shown, to ~n ~nnular groove 152 in the plate 11~7. This groove is connected in turn, and substantially as shown, to the air conduit passageway part 151 in plate 147.
The remainder of the air supply system is formed by a bore 153 ln the plate 146 J ~n annular groove 154 in the same plate~ and a bore 1~5 extended continuously through the boss 143 and the cap 143, this bore having an lnlet at 156.
In drilling the several straight-line bores, or passa~eways, opening~ are created which must then be plugged. Such plugs are shown, but not specially designated.
In order to provlde ~or a laminar flow extrusion system as contemplated by the present invention, in the apparatu~ of Figure 8 the maln extrusion flow derived through the nozzle 140 is supplemented by rlow ~rom a second extruder schematically designated by the numeral 160. The second extruder is connected as by means of conduit 161 to an annular passage 162 ~ormed between a pair Or annular orifice plat8e 163 and 164. These plates, in the apparatus as shown are mounted between the nozzle flange 140a, and the plate 141. In addition to the annular passageway 162 they 122~LS~8 also define an annular orifice 162a opening into the main flow path provided by the other apparatus parts. If desired, the orifice could be restricted to one or more drilled openings communicating with the passageway 162, rather than being a continuous opening.
In operation, using an annular orifice 162a, the extruded material flowing through the central passageway provided by the nozzle and the fixed and rotatable parts mounted thereon, is laminarly coated by the extruded material released through the orifice from the extruder 160. Additional materials may be similarly introduced to produce any desired degree of lamination.
By rotating the die structure, any gauge variation induced by inequalities in the orifice will be regularly distributed in helical fashion in the extruded annularly shaped film discharged. Additionally, if the orifice 162a is replaced by one or more individual orifice openings, one or more individual stripes of a second material may be laminated on the main flow stream. As these stripes are discharged from the rotating die orifice they will assume a helical flow path on the extruded tube surface.
The novel apparatus shown in Figures 1 - 8 is capable of producing many types of laminated products, many of which are formed to possess exceptional and unexpected properties.
An illustrative list of products capable of at least semi-solid fluid flow which could be laminated in various combinations follows. Note that this list is representative only and is not to be considered as limiting combinations selected therefrom.

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122~518 Polyacetal Polymethyl methacrylate Ethyl Cellulose Cellulose Acetate Cellulose Acetate Butyrate Cellulose Nitrate Nylon Polyethylene, High, Medium & Low Densities Polypropylene Co-polymerized Polyolefins Polyallomer Polycarbonate Poly I Butene Polychlorotrifluoroethylene Polytetrafluoroethylene Polyfluorocarbon Polystyrene Styrene Acrylonitrile Copolymer Acrylonitrile ~utadiene Styrene Terpolymers Polyvinyl Acetate Polyvinyl Alcohol Polyvinyl Butyral Polyvinyl Chloride Polyvinyl Chloride Elastomeric Compounds Rubber Extrusion Compounds Chlorinated Rubber Hard Rubber Silicone Rubber and Compounds All extrudable thermosetting compounds such as Mylar*, Phenolics & Epoxies Cellophane* & Paper Pulp Compounds Non-Ferrous metals such as Brass, and Aluminum Example 1 As a first example of a film of unusual characteris-tics which can be formed by the novel process and apparatus of the invention, a novel wrap film can be formed which has an extremely wide seal range. It is known that wrap film must have at least a minimum stiffness (known to the industry as "handle"). Handle is that quality whereby the film will not droop or tend to bunch up. However, the film should be capable of being sealed to itself by heat. To this end, wrap film has been formed of a main layer of polypropylene * Trade Mark . ..
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~ ~31 51~3 which provides the requisite stiffness. A layer of poly-e~hylene is then laminated ~o the polypropylene to permlt heat sealing between the overwrapped polyethylene surfaces. To creat a good heat seal~ the sealing temperature must be very accurately controlled. If the temperature were too low, the polyethylene layer would not soften properly for sealing.
If the temperature were too high, the polyethylene layer would be destroyed. In presently used film wrap, thi~ permissible sealing range ~s only from about 240F to 255~ or about 15F.
In accordance with the present invention, a novel wrap is formed which ha~ a ~eal ran~e which i~ extended to the range from 240 F to 320F, or 80F. This permits greater latitude in the design and operation of sealing equipment and also reduces the number Or rejects in any given operation.
More specifically, and as shown in Figure 9, apparatus aacording to the invention can easily extrude laminated fllm 200 having a central polypropylene layer 201 and outer polyeth~lene layer~ 202 and 203. The total thickness Or the film is preferably of the order of 1 - .05 mil with the polypropylene layer 201 occupying 20% of the total thick-ness, while the polyethylene layers 202 and 203 each occupy 40~ of the total thickness. More generally, the center layer 201 can occupy from 5% to 30% of total thickness whlle the outer layers 202 and 203 can each occupy from 45% to 35% of total thickne~s.
Whlle lt may be possible to fabricate the novel film of Figl lre 9 by other techniques, note that the central film 201 ma~ have a thickness of the order of o.oooo66~
It would be extremel~ difficult to handle such thin films in ¦ pre~ently known processes for film lamination.
Z~

1~ 1 .` 1 1! ~22~51fi ~! The film of Fi~ure 9, as indicated above, has been j formed to have the requisite stiffness of a wrap film becau~e of the strong polypropylene central layer. The outer poly-¦ ethylene layers have an increased thickness and therefore anincreased thermal inertia It is believed for this reason that the seal range has been increased to 80F (in the order of 400,' ) when compared to the seal ran~e of presently used jl wrap film of the same total thickness.
¦I Example 2 It has previously not been possible to provide film l which is colored to a metallic hue~ In accordance with the invention,however, it has been found that when the central I layer is of a dyed material and the outer layers are of jl~ transparent material~, that the overall film will take on a metallic hue dependent upon the color of the central layer.
By way of example, in the embodiment of Figure 9, the central polypropylene layer 201 can be colored yellow by the mixture of cadmium yellow in the polypropylene melt. When this layer is coated by tran parent layers 202 and 203 of polyethylene, the film will take on a metallic gold appearance.
Other similar metallic hues can be imparted to the film by ~uitably coloring the middle layer of the film.
In a similar manner, a green pigment has been introduced into the central layer with aluminum fl~ke~ to impart a green color after coating with a transparent coat.
Clearly, any combination of particular materlals ¦ could be used other than the polypropylene and polyethylene ¦I when obtaining the metallic hue effect.
Il Note that the film layers can be of any desired relative l! thickness for this result and that the thickness ratios are not I limited to those given in Example 1.
-1~2i! 518 Moreover, the central layer can be formed as acentral colored stripe covered by upper and lower trans-parent films by use of the apparatus of Figure 8 or by modifying the apparatus of Figures 3, 4 and 5 to inject only a thin stripe from the channel 69.
Thus, some desired pattern of metallic stripes or sections can be formed in the film.
Example 3 It is possible, in accordance with the invention, to form a relatively inexpensive fire-resistant film. By way of example, a film may be formed of a central and main body of fire-resistant polytetrafluoroethylene (melts at 700F), as shown in Figure 10, by layer 210 which may have a thickness in the range of 3 - 10 mils. The outer layers 211 and 212 may then be formed of polyethylene (or Si compounds) havi.ng a thickness of 1 mil. Note that various of the thermosetting materials or silicon compounds could be used as the fire-resistant layer. In this type arrangement, the polyethvlene acts as a lubricant for the extrusion of the polytetrafluoro-ethylene which cannot otherwise be easily extruded. Clearly, other thermoplastics could be used for the outer layers.
The no~el lamination apparatus and method may be further used for the preparation of film materials having tear-strips integrally formed therein. Such materials can then serve as a moisture-proof transparent package which can be conveniently opened by pulling the tear strip.
This type structure is illustrated in Figures 11 and 12 wherein a laminated film is formed of outer polyethylene layers 213 and 214 which may have a thickness of 1 mil, and a central 2 mil thick layer of parallel strips 215, 216 and 217 of polypropylene. Generally, the tear strip thickness will be twice the thickness of the body material of the film.

The strips may be spaced from one another along the full width of material, shown in Figure 11, which would run continuously in the direction of arrow 218. Clearly, the web may be suitably cut and formed into a desired package which would have a relatively strong polyethylene ribbon embedded therein to serve as a tear strip to open the package.
If desired, ribbons 215, 216 and 217 could be dyed a suitable identifying color.

As an alternative to the structure of Figures 11 and 12, tear strips could be formed in the manner shown in Figures 13 and 14. Referring to Figure 14, I have shown a polyethylene web 220 which has groups of polypropylene strips 221, 222 and 223 laminated thereon. The web 220 may have a thickness of 1 mil while the strips could have a thickness of 2 mils.
Each of the groups of strips include three strips such as strips 224, 225 and 226 for groups 221 (Figure 13).
Those regions between adjacent strips are regions of rela-tively low strength. Thus, if a package is formed of selected 20 portions of web 220, and groups 221, for example, surrounds the package, the central strip 225 (which could be colored) could be pulled, with the polypropylene regions between strips 224 and 225, and strips 225 and 226 separating.
Example 4 It is well known in structural fields that a very high strength structure is formed when a high strength stressed skin structure is formed on a relatively weak web;
More specifically, and as shown in Figure 15, a film of relatively thin high strength outer layers 230 and 231 con-nected by a relatively thick, inexpensive central layer 232 has been formed.

Il 122~8 I' Thu~s in Fi~ure 15 outer layer~ 230 and 231 formed of ¦~ ~olypropylene having a thickness of the order of 0~15 mil l (15~ of the total film thickne~s of 1 mll~ joined by a central polyethylene layer having a thickne~s of the order j of 0.70 mil (70% of total thickness). Thus, the film is relatively inexpensive because of the preponderance of polyethylene, but 1~ still very stiff becau~e of the struc- I
tural arrangement. t A similar film wa~ made of 40~ polypropylene, 20% poly- ¦

ethylene (a~ the inner layer) and 40% polypropylene".
l Example 5 ¦ The present invention also permlts the formation of an oxygen tran~mittlng film which ls essential for meat wrap use or the llke. It i~ deslrable to use polyethylene in meat wrap type film becau~e of its low co~t, and easy wrapping characterls tics. However~ when polyethylene has a thicknes~ greater than 0 5 mil, lt wlll block the pas~age of oxygen. However, since lt 1~
now pos~ible to deal with such thin layers in the novel apparatu ! Or thi~ invention, a central oxygen transmittlng body of a ¦ 3uitable vinyl can be laminated with outer film~ of polyethylene, ¦ each of which are under 0,5 mil.
I If desired, the thin polyethylene film could serve a~ the ¦ base material and be laminated to outer layers of ethyl cellulo3e .
Example 6 Film~ presently used for wrapping articles Auch as meat and flowers commonly have moisture condensed therein to obscure the package contents. In accordance with the inventlon, the ¦ main film body (which could be of the type of Example 5) may ¦ have an outer layer laminated thereon of a wettable material ~uch as polycarbonate or polyvinylacetate. Thi~ wettable material will prevent clouding due to conden3ation.

li , ' ,i ~2'.2~ 5~L8 Example 7 Film wraps for cheese must prevent transmission of oxygen gas. Polyethylene, which is inexpensive, prevents 2 transmission, is thicker than 0.5 mil, and, therefore, is desirable for use as a cheese wrap. However, polyethylene reacts with cheese, and, therefore, could not be used in the past, but relatively expensive vinyls have been used instead.
In accordance with the invention, a novel cheese wrap having a total thickness of 1 mil is formed of a central polyethylene base having vinyl layers laminated to its outer surfaces. The central polyethylene body may have a thickness of the order of 0.7 mil, while the outer vinyl layers would have a thickness of 0.15 mil.
Example 8 In accordance with the invention, a central laminate of a flocking type material such as glass fibers which are plasticized in a plastic material may be laminated between the outer polyethylene surfaces. The thickness of the central layer may be 5 mils, and the thickness of the outer poly-ethylene surfaces may be 1 mil. The flocking material willnow be coated by a smooth outer surface and will not be rough to the touch~
The foregoing examples have all been for the use of the novel products formed by the invention as wraps or containers. I have discovered that the novel method of the invention is also useful for the formation of novel electrical-type components. More specifically, the present invention further contemplates that one of the laminated products may be a conductive-type material which can be laminated with in-sulation materials in various geometrical arrangements forthe formation of electrical resistors, capacitors and inductors.

p -28-` '~LZ;2 ~8 Example 9 Another important product and method, in accord-ance with the present invention, is in the formation of prestressed film or sheets wherein the film tends to curl.
When this type film is used for the making of bags, the free ends of the bags will tend to curl inwardly or outwardly, thereby biasing the bag open. This novel arrangement is illustrated in Figures 22 and 23 which show a bag 240 having sealed edges 241, 242 and 243. Note that the bag could be formed of flat or tubular film. Where the bag is tubular, the bottom edge 242 is formed by sealing in the usual manner. The film is then formed of outer polye~hylene layer 244 having a thickness of 1/2 mil, a central layer 245 of polypropylene having a thickness of 1 mil and an inner layer 246 of polyethylene having a thickness of 3 1/2 mils. The upper edges 247 and 248 are seen to curl inwardly thereby biasing the bag open. This novel result is achieved by using different melt temperatures for the inner and outer layers 246 and 244 respectively. That is to say, when the product of Figures 22 and 23 is formed in the apparatus of Figure 1, the polyethylene melt from the extruder connected to channel 35 will be at a different temperature than the melt from extruder 34. Therefore, the cooling rates of the two layers are different so that, upon crystalization of the materials, there will be a built in stress tending to cause the material to curl as shown.
Note that this effect can be obtained from the differential cooling of at least two similar or dissimilar materials. Moreover, note that both channels 35 and 36 could be connected to the common extruder 34 with suitable heaters connected to the conduits leading to channel 35 to cause the difference in melt temperature.

12Z~18 The electrically conductive laminate or strip will be formed by a conductive-type material carried in a plasticized carrier. By way of example, a large concentra-tion of carbon particles can be plasticized in a polypropylene mix so that a strand having relatively high conductivity as compared to normal polypropylene can be extruded in a film or sheet form.
A suitable material can be formed of a plasticized mixture of 15% powdered bronze metal, 60% graphite or carbon power and 25% polypropylene. Clearly any desired thermo-plastic material can be used as a carrier vehicle for the conductive substance.
As a first embodiment of the invention for appli-cation to electrical device, Figure 16 illust~ates a five-ply structure which has two conductive layers 260 and 261 which are separated by a high dielectric layer 262. Layer 262 can, for example, be of polypropylene having a thickness of 5 mils, while layers 260 and 261 are electrically conductive layers formed of carbon powder particles embedded in a polypropylene carrier. The spaced conductive sheets 260 and 261 can then define the electrodes of a capacitor. Additional insulation layers 263 and 264 which can, for example, have a thickness of 1/2 mil and may be of polyethylene are then placed on the exterior of conductive electrodes 260 and 261 so that if these electrodes are rolled into a tight, rolled package, the opposite surfaces of the capacitor will now be short-circuited. When access is required to one of the conductive layers for the connection of an electrical lead, the thin insulation coatings 263 and 264 can, of course, be easily scraped away.

.

~2ZlS3~8 The structure of Figure 16 can, of course, be drawn from apparatus of the type shown in Figures 1 and 2 wherein the full web width is sliced into segments having a width of, for example, 1 inch, with these 1 inch sections being rolled up on a suitable roll. The structure may then be rated as having a certain number of micromicrofarads per inch, whereby a user, after determining the amount of capacitance which he needs, will simply cut off a suitable length from the roll and his capacitor will be available to h~m.
While Figure 16 illustrates the application of the invention for electrical capacitors, it will be apparent that the conductive material can, by the use of a suitable density of carbon power in the plastic carrier, have a controlled resistance per linear dimension.
Accordingly, electrical resistors can be formed where, for example, as shown in Figure 17, a die of the type shown in Figures 3 and 4 can extrude a central resistance strip 270 which has a predetermined amount of carbon embedded, for example, in polypropylene which is coated by an outer sheath 271 which could, for example, be of pure polypropylene.
Here again, the strip is wound on a roll and an electrical designer, after determining the resistance he desires, will cut off a suitable length for his purpose. Clearly, the struc-ture of Figure 17, when having suitable conductivity, can serve the general purpose of any insulated conductor.
Another manner in which the lamination technique of the invention may be used is illustrated in Figures 18 and 19 wherein conductive strands of plasticized material containing conductive powder are embedded in a pure insula-tion medium for the formation of multi-stranded cable.

12Zl~
Thus, a body 2~0 whlch could, for example, be of polypropy-lene has embedded therein continuous strands such a3 strands 281 and 282 of polypropylene havinG masticized therein carbon powder or the like. This arrangement which can be extruded by any deslred technique will then produce a cable having continuous conductors which are insulated ~rom one another, where any desired number of conductors or filament~
can be embedded in the insulation carrier body.
Figures 2~ and 21 illustrate a further application ~f the invention for the formation of electrical components ¦
wherein an inductance winding having a magnetic core is formed in a unitary operation. Thus, in Figures 20 and 21, a central core member 290 is formed of some suitable plastic material having3 for example, lron filings embedded therein to produce a relatively high permeability ~tructure. During the extrusion o~ this material, an outer electrical insula-tion layer 291 is formed on the magnetic body 21, while a splralling conductive stripe 292 winds around magneti¢ core 290.: Note that in~ulatlon layer 291 prevents short-circuiting between the turn~ of the wlnding 292. The winding stripe 292, which can be of any ~uitable plastic carrier havlng conductive particles emb~dded thereinl is caused to wind throughith~
u~e of a rotating die structure of an arrangement similar to that of Figure 8.

Claims (10)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. An extrusion apparatus for extruding laminated plastic products including an extrusion die defining a flow path for fluid products and having a discharge orifice comprising, an annular plate member having a passageway therethrough defining a portion of said flow path having an outlet, a flow diverter in said passageway adapted to divide said passageway into at least two separate and spaced flow channels, at least one conduit passageway defined in said diverter to open toward said plate passageway outlet in substantially parallel flow relation with said spaced flow channels, said passageway being adapted to be connected to a first extruder by means extending through said annular plate, said conduit passageway in said diverter being adapted to be connected to a second extruder whereby materials flowing from each of said passageways are laminarly joined under pressure before extrusion through said discharge orifice, said flow path having a diver-gent portion toward said discharge orifice whereby said laminarly joined extruded materials are laterally extended prior to discharge from said discharge orifice.

2, The method of forming a laminated body comprising the steps of joining the flow of a first molten material into laminar flow with at least one additional molten material, the materials being joined under pressure, and thereafter moving said joined materials with laminar flow in a divergent flow path toward an orifice opening and extruding said joined materials through said opening.

3. The method of claim 2 wherein a further plasticized material having laminar flow is joined to said first and second plasticized materials under pressure and prior to extrusion.

4. The method of claim 2, wherein said lamin-ated body is a sheet or film.

5. The method of claim 4, wherein said film has a thickness of less than 10 mils.

6. The method of claim 4, wherein said first and additional molten materials comprise dissimilar thermoplastic polymers defining interfaces therebetween.

7. The method of claim 5 or 6 wherein said molten materials are joined in an extruder into over-lying and coextensive fluid films defining therebetween interfaces without intermixing of the said molten materials, said fluid films being laterally extended and extruded through a common extrusion film die orifice to provide a thin film having coextensive integral and uniform layers of said molten materials.

8. The method of claim 2 wherein the materials are selected from the group consisting essentially of: poly acetal, poly methyl methacrylate; ethyl cellulose; cellulose acetate; cellulose acetate butyrate; cellulose nitrate; nylon;
polyethylene, high, medium and low densities; polypropylene;
copolymerized polyolefins; polyallomer; polycarbonate; poly I butene; polychlorotrifluoroethylene; polytetrafluoroethylene;
fluorocarbon; polystyrene; styrene acrylonitrile copolymer;
acrylonitrile butadiene styrene terpolymers; poly vinyl acetate;
poly vinyl alcohol; poly vinyl butyral; poly vinyl chloride;
poly vinyl chloride elastomeric compounds; rubber extrusion compounds; chlorinated rubber; hard rubber, and silicone rubber.

9. The method of claim 2, wherein the materials are selected from the group consisting essentially of: poly-propylene; polyethylene (high, medium and low density);
polyvinyl chloride; polyvinyl acetate; styrene acrylonitrile copolymer; acrylonitrile butadiene styrene terpolymer; nylon, and polymethylmethacrylate.

10. A process for extruding multiple thermoplastic resins, comprising:
(a) supplying separate streams of thermoplastic resins into an extrusion apparatus and causing the streams to combine therein in a flowing manner to form an interface between said streams;
(b) causing the combined streams to flow laminarly without any mixing across the interface between the thermoplas-tic resin streams so as to maintain the physical integrity of each stream in said combined stream;
(c) altering the overall cross-sectional geometric configuration of the combined stream within a forming die thereby providing a thermoplastic resin extrudate exiting said die, having a coextensive, integral, and uniform configuration of said thermoplastic resins in said extrudate.