CA2180882A1

CA2180882A1 - Substructure for composite products and products formed therewith

Info

Publication number: CA2180882A1
Application number: CA002180882A
Authority: CA
Inventors: Vic De Zen
Original assignee: Royal Ecoproducts Ltd
Current assignee: Royal Ecoproducts Ltd
Priority date: 1996-07-10
Filing date: 1996-07-10
Publication date: 1998-01-11
Also published as: PL331042A1; WO1998001275A1; AR007839A1; CO4810239A1; AU3331797A; PE89098A1; CN1228729A; ZA976000B; BR9710254A; AU730567B2; JP2000514006A; US6253527B1; EP0921920A1

Abstract

A substructure for a composite product comprising a compression molding of particulate materials encapsulated and bound together by a thermoplastic binder into a compacted mass of a shape selected for its own use and composite products formed from such substructures. The particulate material comprises waste or recycled material and is chosen to control the physical properties of the substrate and products formed therefrom, and the thermoplastic binder comprises recycled thermoplastic material.

Description

2 1 80882 SUBSTRUCTURE FOR CO~IPOSITE PRODUCTS
AND PRODUCTS FORMED THEREWITH

FIFT .nOFTT~ TiQN
This invention rela~es to products of the type which presently use wood, plywood or other board or the like as the supporting substructure or 10 base.
B~CKGROTJND OF~TF I~ ON
There are at presenl. a large number of composite products which use wood, plywood or the like as a substructure or base to provide the requisite physical properties such as tensile and structural strength, rigidity and shape to which surface ~f~hmPnt~ or covers can be screwed, nailed, glued or other~vise fastened or attached.
Typical examples iIlclude insulated steel doors which use a perimeter frame of wood to which steel sheeting is applied on opposite sides thereof and the frame then fill~d with foamed insulation.
Other examples include wood door and window frame profiles whose exposed surfaces may l~e covered or clad, for instance, with plastic or ~Illminillm, or wood clad door panels used in folding or swing doors for garages or for truck or other vehicle doors and the like.
With such present composite products, the physical properties of the available sub~ilu~Lult;s are relatively limited being ~If~f~rmin~d by the selection of the wood, plywood or other board which is produced by conventional m~ f~rfllrin~ processes.
-Moreover, sl-hst~nti:~l wastage of wood by splintering, warping or by virtue of imperfections occurs in the m~mlf~rtllrin~ processes, and often the final product substructure is subject to water absorption, warping, min~tion and rotting.
Further, if other than conventional regular shapes of such materials, such as square or rectangular, are required for their end use, such shapes must be fabricated by sawing, cutting andlor assembling individual pieces and securing them together with nails, screws or other fastening means.
SUMMAI~Y OF TI~F TNVFN~ION
The present invention is directed to providing a very low cost and very durable substructure having superior qualities to the wood and wood 15 products ~Ub:~llU~,~Ult~S presently used in many cornmercial products thereby reducing the cost and enhancing the value of such products.
Further the invention provides an important environmental benefit in that it enables present waste materials to be converted into a highly useful 20 structural ~;U~ O~ whose shape can be accurately controlled to suit its intended end function. In addition, the invention enables the physical properties of the structural component or substructure to be selected over a wide range of variables to accord with the properties of the cladding or covering applied thereto and the intended use of the end composite product.
Additionally, the invention enables the desired shape of the structural component or substructure as well as its physical properties to be effected in the m~nllf~tllrin~ process without, or essentially without, any subsequent fabrication.
More particularly, clccording to the invention, the structural ~o~ o~ or substructure is a compression molding ~,UlU~ illg a particulate material s~lected to control its physical properties ~n~s~rslll~t~d and bound together by a thermoplastic binder into a compacted mass of a shape selected for its end use.
Further, according to the invention, the substructure is incorporated 5 into a composite product in ~hich the substructure is used to support a covering or cladding covering at least a portion of the surface thereof.
The Pnr~rs~ on of the particulate material by the thermoplastic binder according to the invention enables the effective use of waste or 10 recycled materials, such as reground low, medium, and high density polyethylene, polypropylene, polyethylene terephthalate (PET), nylon, PVC, ABS, and other ground up thermoplastic and/or thermosetting polymeric material.
Other particulate material which can be advantageously used are fibrous materials such as woo~ particles, i.e. sawdust, ground up wood pieces, ground cloth, paper and glass fibers.
Still other examples of particulate material that are useful for the 20 substructure are waste materi~lls such as fly ash, kiln dust, ground peanut shells, rice husks or corn husks.
Thus, it will be a~ cia~t;d that the invention enables the production of highly useful pl oducts while at the same time achieving 25 important environmental benefits by using up waste material which would other~vise have to be dispose(l of at an d~lU~lia~ site.
It will be understood that various mixtures of particulate material can be used as desired or required. For instancej the inclusion of the fibrous

3 o particulate material provides ~ood control of the expansion properties of the ~iUb~llU-,~Ult~, a necessity wheie the end composite product such as a door frame or panel whose shape and size is governed by the substructure is exposed to a wide range of tt~ a~ulciS during the year.

2t 80882 Again, the use of particulate material such as fly ash, glass pa~ticles, kiln dust imparts strength and rigidity to the substructure in the composite product of which it forms the base.
The thermoplastic binder also is preferably a recycled thermoplastic such as PVC or one of the polyethylenes or a mixture of recycled thellllu~l~li~, materials whose melting points are relatively similar. In this way, the entire ~ub~llu~ can comprise recycled or waste materials molded into a highly useful c-lmr~f~d structural ~ollll,oll~llt exhibiting the selected 0 physical properties. It will be understood that such a c~mron~nf will be free from water absorption, warpillg, splintering or otherwise deteriorating under its intended use.
The amount of thermoplastic binder per weight of the substructure can vary from about 10% to .Ibout 90% by weight with the encapsulated particulate material varying fiom about 90% to about 10% by weight of the ~ub~ depending upon the end use of the composite product for which the substructure is the base.
2o For most uses, the 11Ir~ I;C binder should comprise from about 40% to 60% by weight and tl~e physical property controlling particulate material from about 60% to about ~0% by weight of the substructure.
Because the ~ub:,uu~lu-~; of the invention is a molding, it will be understood that it can be pro~iuced in a very wide range of shapes without having to be fabricated for use as the base for a very wide range of products.
Examples of such products of the invention comprise insulated steel doors, door frame profiles for housing and garages, window frame profiles, swinging door panels, folding door panels for buildings or vehicles, or other products 3 o where the profile, shape and E)hysical ch~r~rfPricf~ of the final product depend upon t_e substructure.
Further, it will be understood that while the compacted nature of the substructure makes it a solid sturdy structure, and the ~n~rg~ fion of the particulate material by the th~l mf)rl~fiC binder renders it impervious to moisture, insects, rotting, and ~he like, nevertheless it can be readily drilled, cut or machined and will readily accept and retain nails, screws, staples or other fasteners. Surface covering Ol~ other exterior ~ff~hm~nt~ can also be readily 5 bonded thereto using UUIlUUt;l'.,i~l industrial adhesives.
Bl'~TFF DF~~CRTPTION C)F Tl TF. DRAWINGS
Figure 1 is an exploded perspective view showing the u~ rOI~r~
of a composite steel door having a compression molded substructure frame in accordance with the inventioll.
Figure 2 is a cross section on the line 2-2 of Figure 1.
Figure 3 is a cross section on the completed door showing the interior filled with an insulation material.
Figure 4 is a brokell away cross sectional view through one of the 20 vertical edges of the door which has been grooved to receive a plastic cap.
Figure S is a p~l~e~,liv~ view illll~trPtin~ the molding operation in which a rope of th. ~ ;r binder heated to a flowable viscous state and containing ~i ~ material is deposited in a mold ready for compression.
Figure 6 is a section on line 6-6 of Figure 5.
Figure 7 is a cross sectional view showing the application of pressure to compact the material laid into the mold cavity.
Figure 8 is a view similar to Figure 7 showing the ~ub~llu-,lu material after it has been c~ mp~nt~l .

Figure 9 is a perspective view illustrating the assembly of a composite panel comrri~in~ a compression molded substructure in the form of a frame ready to be introduced between cover sheets or panels.
Figure 10 illustrates a substitute frarne for that shown in Figure 9 in which the frame comes in two sections.
Figure 11 is a cross sectional view of the assembled panel of Figure 9 and showing the introduction of insulating foam into the interior thereof.
Figure 12 is a cross sectional view of a typical window profile comprising a compression molded ~ub~llu~lu~ in which exposed surfaces are covered with attached sheathing.
Figure 13 is a view similar to Figure 12 but showing a typical door frarne profile.
Figure 14 is a p~l~e-,live view illustrating the assembly of a door frame in which the profiles ha.ve been ~:ol~ h)ll molded to ~
profiles ready to support clad~ing on exposed surfaces where desired.
Figure lS is a p~ e~ive view of a truck illustrating a folding rear door made up of a series of panels which can be hinged together in any desired manner (the hinges not being shown).
Figure 16 is a sectional view on the line 16-16 of Figure 15 showing the C(JIllL~ iull molded subs~ructure to which a cover or sheathing has been attached covering the outer alld edge surfaces of the substructure.
Figure 17 is a view similar to Figure 16 but showing the substructure entirely sheathed.
Figure 18 is a rear end view of a truck of the type using a pair of vertically hinged swing doors.
.

~ 2~80882 Figure 19 is a cross sectional view on the line 19-19 of Figure 18 showing the composite struch1re of the door panel in accordance with the invention with the door panel in this example being fully clad or sheathed.

DETAILED DESCRIPI ION ~CCORDING TO THE PREFERRED
10 F~ oDl~ENTsOFTHEPRESENTINVENT~ON
The assembling of the steel door 50 illustrated in Figure 1 is simply one example of a composite product according to the invention using a substructure according to the invention.
As illustrated, the door is made up of a frame 1 c- mrricing a compression molding of particulate material Pn~lr~ tP-I and bound together by a thPrm-~rl~c~i~ binder as h~reinafter more fully described. This frame formsthe substructure to which steel cover plates 2 are secured by any suitable 2 o means such as nails, screws, illdustrial glues.
When ~gPmhlPfi, tlle hollow interior of the frame can then be filled with insulating material 3 such as foamed polyurethane which can be introduced into the interior of the frame through a bore ~ illustrated in Figure25 1 drilled through the frame which is further provided with bleed holes 5 to allow for the escape of air from the interior of the frame during the foaming operation.
As the substructure involved, that is the frame 1 in Figure 1, 3 o according to the invention is resistant to paint applications, the exposed vertical edges of the substructure frame can be grooved as at 6 to receive and retain an edge plastic cover 7.

As illustrated in Figure 1, the frame 1 is provided with an inward projection 8 registering with a hole 9 in the front cover plate or panel 2 for the mounting of the door handle or knob and the associated latching mP~h:lnicm (not shown).

Figure 5 shows the mold 10 for molding the frame 1 which comprises a channel 11 ~ .sl,u~ldillg to the shape of the frame 1 and into this channel is laid a rope 12 of sul~structure material forced out of nozzle 13 either by screw feed or ram ejection from feeder 14 which is caused to move around 10 the channel 11 as it delivers its feed by any suitable means, preferably a robotic device (not shown).
The rope 12 comprises a thermoplastic binder which has been heated to a molten or flowabl~ viscous state and contains a particulate material selected to control or define the physical properties of the substructure such as strength, hardness, co-efficient of expansion and the like.
Figure 6 which is a cross section showing the molten rope after it has been laid down in the chalmel 11 and settles in the channel illustrates 20 diagr~mm~ti~:llly the molten ~hPrmorl~ material lS and the particulate material at 16.
Figure 7 shows the platen 17 brought down to apply pressure to the molten rope to compact it into a dense mass as illustrated in Figure 8 in 25 which the particulate material 16 is Pnr~r5~ P~I by the ~ lw~Lli,lic material 15 which has been caused to flow around same under pressure and to then bind same together into a solid crmr~Pd mass on the cooling and hardening of the ~ ""~ material.
The selection of the particulate material 16 and the ratio of the tll~llllOpla~lic material will depend upon the end use of the door 50. Where the door will be exposed to substantial Itilllpt~ld~Ult; changes, the particulate material preferably comprises at least in part a fibrous material such as saw dust or cloth or paper particles The tll~llllopla~lic material 15 preferably 2 1 80~82 comprises recycled PVC or polyethylene and the ratio by weight would preferably be of the order of about to 30% to 60% particulate material with the balance being the thermoplastic binder material or principally thermoplastic binder together with some additional particulate material such as 5 fiy ash or kiln dust to impart llardness and strength.
It will be appreciated that because that substructure involves particulate material r~nr~rs~ d and bound together into a compact mass, it not only affords the ability to use waste particles that would otherwise pose a 10 disposal problem but to use them very advantdgeously to control or define thephysical properties of the ~ub~llu~lu~. At the same time, since the function of the th~ o~L,lic binder is to encapsulate and bind together the particulate material, recycled thermoplaslics can also be used advantageously rather than discarded so that the entire substructure can be totdlly of recycled or waste materials so that it can be pro(~uced at a very low cost.
From an ~IIVilOlllllt;llt21l point of view, it will be d~ 1 that it is not necessary to cut down trees to obtdin access to wood fibers which may take the form of sawdust or ground up splintered wood or other wood~ 0 wastdge which can serve as the particulate material. In addition, it will be that the basic shape of the composite product is or can be rl~f.ormin~d by the shape of the substructure which can be molded into such shape without having to be fql~rir~r~l On the otber hand, the substructure can be readily cut, drilled, and machined ready for ~ft~rhmrnf of the materials 25 to be supported thereby by conventional fasteners or industrial glues. It will also be lln~lP~fr,od that the substructure can be clad or sheatheed with a cover layer eg. of rubber or la~ex by dipping or other like processes.
With the particulate material enrs~r~llls~f~d by the thermoplastic 3 o material during the compression molding, as explained, a very wide range of particulate material can be advantdgeously employed. Recycled or reground fhr. ~ ir materials whose melting point is above the thermoplastic material which is heated to the molten state in the molding process to coAstitute the binder can serve as a useful particulate. Also useful are ~ 2180882 reground or recycled illrl ",~.s,~ plastics. As mentioned, examples of recycled plastics include reground low, medium and high density polyethylene, polypropylene, polyethylene terephthalate (PET), nylon, ABS
and PVC. In the fibrous group of useful particulates, ground up scrap wood 5 along with saw dust, ground cloth, paper give expansion control and for hardness short fine glass fibeIs are useful. Typical other waste particulate materials which give structur~ll strength include fly ash, kiln dust, ground peanut shells, ground rice husks and corn husks.
It will be understood also that combinations of these various particulate materials can be used to select the requisite physical properties ofthe ~ub~llu~ according to the nature and use of the composite end product for which the substructure forms the base.
In preparing the mixture of the thermoplastic binder and the particulate material selected to provide the desired physical properties of the substructure, the material is heated together until the thermoplastic material or materials with the lowest melting point become molten to the point that they can fiow as a viscous stream carrying the particulates contained therein so 2 o that the mixture can be delivered as a stream or molten rope l 2 into the mold lO. Any remaining still solid particulate thermoplastic material will then serveas part of the ~ particulate material if other particulate materials are present, or will form the remainder of the ~ul"u u~lu.~; if other particulate materials are not present.
Preferably the thc;l~lv~!k~i~lic material forming the binder Ct)nCti a substantial percentage by weight of the substructure and is recycled or reground tll~llllv~la~lic mateIial. However, there may be instances where the substructure would be accept~ble if the ~ llllo~ Lic binder material 30 constituted down to about lCI% by weight of the substructure in which case the cost of the molding would not be illOl~' ~'y high if the thermoplastic binder were not a recycled Illr~ liç

2 1 $9~82 Also, while not takilg full advantage of the invention, because of its very low cost, calcium carbonate may be used as a property controlling ~qn~rs~ d particulate.
Figure 9 again illustrates the use of a substructure 18 in the form of a rectangular frame for forming a composite product comrricin~ an insulated panel 19. In this case, the bUb~LlUC,~UI~ frame 18 is inserted between a pair ofcover plates or cladding 20 wl1ich are screwed, nailed or otherwise secured to the frame 18 and the interior filled with a foamed insulation 21 as in the case of 0 the steel door S0. The cover plates 20 may be of suitable material which would include steel, aluminurrl or plastic sheeting.
While c~ v~lu~u~ly the ~Ub~UU~ 18 is a complete frame, it will be appreciated that the substmcture may be made up of individual parts such as the half frame sections 22 shown in Figure 10.
Again the choice of the particulate material will depend upon the end use of the panel and also ~n the properties of the material forming the cover plates or cladding 20 with the fibrous particles being useful for expansion control and such p~rticulates as fly ash being useful for hardness.
Figure 12 illustrates a substructure 23 which has been compression molded into the shape of a window frame profile with exposed surfaces having cladding 24 of plastic or metal secured thereto.
In Figure 13, the compression molded :;Ub:>llU-,~Ul~ 25 is in the form of a door frame profile having cladding 26 in the form of plastic or metal secured to exposed surfaces thereof.
The selection of the particulate material of the substructures 23 and 24 in the form of the window and door frame profiles respectively is selected for their end use application. Where they are to be used in locations ~I,P. i~ wide It~ ld~Ule changes, the particulate material preferably .

includes a sigluficant proportion of fibrous particles up to the order of 30% of40% by weight of the substructure.
While completely f~lbricated composite products such as the door 5 50 or the panel 19 can have the ~ lUl;~Ult~ frame molded as a complete unit where frames such as the door and window frames of Figures 13 and 12 respectively are being incorporated into the construction of a house or other building, ;lfijllc~mf nf~ are likely to be required, for instance in the length of the door side frames indicated at 27 in Figure 14. Therefore these side frames are 10 delivered to the job in lengths ' ~i~liy longer than the height of the door frame so that they can be cut l:o the d~pl~,lJ length on site.
Figure 14 illustrates the fabrication of the door frame in which the side frames 27 are secured to a sill frame 28 and a header frame 29. All of 15 these frames comprise compression molded substructures of particulate material; ~ ' ~ and bound together by a thermoplastic binder as discussed above. Suitable cladding covering exposed surfaces of the door frame can be secured to the ~iUb~ UI~ through the use of screws, nails or other fasteners. Additionally ~)r alternatively, the cladding may be secured by 20 providing grooves 30 in the sllbstructure such as illustrated in Figure 13 and the cladding can be provided ~vith inturned fingers 31 as illustrated in Figure 13 to engage in the grooves 3(D.
Similarly, with respect to the window profile substructure 23, the 25 cladding 24 can have inturned fingers 32 engaging in grooves 33 formed in the ~Ub~llU~,~UI~ 23 as illustrated in Figure 12.
Another area where wood is widely used as a subst~ucture is in the construction of truck door par els where the use of the substructure of the 3 o present invention provides an importdnt saving in wood while, at the same time, providing enhanced physical properties of the doors f limin~lin~ warping, rotting, ~1fl- "; -~;"~, being inlpervious to water and insect attdck.

Figure 15 diagramrnatically illustrates a truck 34 having a folding rear door generally ~'iP~i~nsitpd at 35 made up of a series of horizontal door panels 36 pivotally connected together by suitable hinging (not shown).
~ CI,U1d~ with the preserlt invention, these door panels 36 comprise a composite product constituted by the substructure 37 shown in Figure 16 comprising the themloplastically Pn~rslll~it~d and bound particulate material defining the panel shape having a cladding 38 secured thereto covering the exposed rear face of the panel. Again, the particulate 0 material and the quantity thereof will be selected to meet the desired physical properties for the door panel 36. By the use of the recycled or waste particulate material, not only can a significant cost reduction be made from present door panels of the type illustrated by the door panel 36, but such panels utilizing the substructulre of the present invention will be s~h~tS~nti,illy superior to those presently in use.
While Figure 16 illustrates the substructure 37 has been clad on the outside and edges, the entire ~u~ u~lul~ 36 can be completely clad by the cladding 39 illustrated in Figure 17.

Figure 18 illustrates another door ,irr~n~PmPnt widely used on the rear of trucks such as the truc!k generally f'~P~igJn~itPd at 40. In this case, the door all~lg~ t comprises ~ pair of door panels 41 secured by hinges 42 at their outer edges and arrange(l to swing together to meet in the center where they can be secured by a suitable lock a~ lg~ t generally ;P~i~n,itPd at 43. At present these panels 41 comprise large plywood panels which may be covered as desired. If the plywood panels should chip or splinter, as is frequently the case, they become waste products adding to the enormous amount of wood that is involved in their production. Moreover, again, such 3 o door panels are exposed to all types of weather and are subject to deterioration.
By the use of the pl esent invention, such door panels can be provided at a tremendous saving in costs while elimir~tin~ the cutting down 2 ~ 8o882 of many trees and at the sam~ time improving the ~lIV~ by utilizing waste or recycled materials. ~rhus, as illustrated in Figure 19, each of the panels 41 is formed of a substructure 44 of particulate material ~nr~rg~
and bound together by a thermoplastic binder provided with a cladding 45 5 secured thereto.
~ rhe cladding 45 m~ly be plastic or metal such as thin aluminum or steel sheeting and, if desired, can be used to cover only the outside faces of the door panels 41.

It will be understo~d that only a limited number of examples of composite products have beel1 illustrated and that the compression molded substructure can take many different shapes for many different products and can be clad or covered with an exterior sheath not only mechanically or 15 adhesively but by a dipping process or the like. It is intended that all such products fall within the scope of the appended claims.

Claims

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

1. A substructure for a composite product comprising a compression molding of particulate material encapsulated and bound together by a thermoplastic binder into a compacted mass of a shape selected for its end use.

2. A substructure as claimed in Claim 1 in which said particulate material is a recycled material.

3. A substructure as claimed in Claim 2 in which said thermoplastic binder is a recycled thermoplastic material.

4. A substructure as claimed in Claims 1, 2 or 3 in which said particulate material comprises from about 10% to about 90% and said thermoplastic binder comprises from about 90% to about 10% by weight of said substructure.

5. A substructure as claimed in Claims 1, 2 or 3 in which said particulate material comprises from about 30% to about 70% and said thermoplastic binder comprises from about 70% to about 30% by weight of said substructure.

6. A substructure as claimed in Claims 1, 2 or 3 in which said particulate material comprises from about 40% to about 60% and said thermoplastic binder comprises from about 60% to about 40% by weight of said substructure.

7. A substructure as claimed in Claim 1 in which said thermoplastic binder and said particulate material are recycled materials with said thermoplastic binder comprising from about 30% to about 70% and said particulate material comprising from about 70% to 30% by weight of said substructure.

8. A substructure as claimed in Claim 7 in which at least some of said particulate material is a recycled fibrous material.

9. A substructure as claimed in Claim 8 in which said recycled fibrous material is selected from one or more of wood, cloth or paper.

10. A substructure as claimed in Claim 9 in which said fibrous material comprises from about 30% to about 60% by weight of said substructure.

11. A substructure as claimed in Claims 8, 9 or 10 in which said particulate material also includes ground recycled plastic material.

12. A substructure as claimed in Claims 8, 9 and 10 in which said thermoplastic binder comprises recycled thermoplastic material.

13. A substructure as claimed in Claim 1 in which said thermoplastic binder comprises recycled thermoplastic material comprising from about 40%
to 60% by weight of said substructure and said particulate material comprises recycled material comprising from about 60% to 40% by weight of said substructure, said recycled particulate material being selected from one or more of reground low, medium and high density polyethylene, polypropylene, polyethylene terephthalate, nylon, ABS, PVC, saw dust, ground wood pieces, ground cloth, paper, glass, fly ash, kiln dust, ground peanut shells, rice husks, corn husks, and mixtures thereof.

14 A composite product comprising a compression molding of particulate material encapsulated and bound together by a thermoplastic binder into a compacted mass shaped to conform to the desired shape of said composite product, and a cover material attached to said substructure and covering a least a portion of the surface thereof.

15. A composite product as claimed in Claim 14 in which said particulate material of said substructure is a recycled material.

16. A composite product as claimed in Claim 14 in which said thermoplastic binder is a recycled thermoplastic material.

17. A composite product as claimed in Claims 14, 15 or 16 in which said particulate material of said substructure comprises from about 10% to about 90% and said thermoplastic binder comprises from about 90% to about 10%
by weight of said substructure.

18. A composite product as claimed in Claims 14, 15 or 16 in which said particulate material of said substructure comprises from about 30% to about 70% and said thermoplastic birder comprises from about 70% to about 30%
by weight of said substructure.

19. A composite product as claimed in Claims 14, 15 or 16 in which said particulate material of said substructure comprises from about 40% to about 60% and said thermoplastic binder comprises from about 60% to about 40%
by weight of said substructure.

20. A composite product as claimed in Claim 14 in which said thermoplastic binder and said particulate material of said substructure are recycled materials with said thermoplastic binder comprising from about 30%
to about 70% and said particulate material comprising from about 70% to 30% by weight of said substructure.

21. A composite product as claimed in Claim 20 in which at least some of said particulate material of said substructure is a recycled fibrous material.

22. A composite product as claimed in Claim 21 in which said recycled fibrous material of said substructure is selected from one or more of wood, cloth or paper.

23. A composite product as claimed in Claim 22 in which said fibrous material of said substructure comprises from about 30% to about 60% by weight of said substructure.

24. A substructure as claimed in Claims 20, 21 or 22 in which said particulate material of said substructure also includes ground recycled plastic material.
25. A substructure as claimed in Claims 20, 21 and 22 in which said thermoplastic binder of said substructure comprises recycled thermoplastic material.

25. A composite product as claimed in Claim 14 in which said thermoplastic binder of said substructure comprises recycled thermoplastic material comprising from about 40% to 60% by weight of said substructure and said particulate material comprises recycled material comprising from about 60% to 40% by weight of said substructure, said recycled particulate material being selected from one or more of reground low, medium and high density polyethylene, polypropylene, polyethylene terephthalate, nylon, ABS, PVC, saw dust, ground wood pieces, ground cloth, paper, glass, fly ash, kiln dust, ground peanut shells, rice husks, corn husks, and mixtures thereof.

26. A composite product as claimed in Claim 14 comprising a door and said substructure comprises a rectangular frame defining the perimeter of said door, and said cover material comprises a cover panel secured to each side of said frame.

27. A composite product as claimed in Claim 26 in which said frame is filled with insulating material between said cover panels.

28. A composite product as claimed in Claim 27 in which said cover panels are steel sheets.

29. A composite product as claimed in any of Claims 26, 27 or 28 in which said particulate material of said substructure comprises from about 40%
to about 60% and said thermoplastic binder comprises from about 60% to about 40% by weight of said substructure.

30. A composite product as claimed in Claims 26, 27 or 28 in which said thermoplastic binder and said particulate material of said substructure are recycled materials with said thermoplastic binder comprising from about 30%
to about 70% and said particulate material comprising from about 70% to 30% by weight of said substructure.

31. A composite product as claimed in Claim 14 comprising a door frame member and said substructure has a door frame member profile and said cover material covers surfaces thereof which are exposed when said door frame member is incorporated into a door frame.

32. A composite product as claimed in Claim 31 in which said thermoplastic binder and said particulate material of said substructure are recycled materials with said thermoplastic binder comprising from about 30%
to about 70% and said particulate material comprising from about 70% to 30% by weight of said substructure.

33. A composite product as claimed in Claim 14 comprising a window frame member and said substructure has a window frame profile and said cover material covers surfaces of said window frame member which are exposed when said window frame member is incorporated into a window frame.

34. A composite product as claimed in Claim 33 in which said thermoplastic binder and said particulate material of said substructure are recycled materials with said thermoplastic binder comprising from about 30%
to about 70% and said particulate material comprising from about 70% to about 30% by weight of said substructure.

35. A composite product as claimed in Claims 33 or 34 in which said cover material is selected from plastic steel or aluminium.

36. A composite product as claimed in Claim 14 comprising a door panel and said cover material covers at least the outer face of said door panel.

37. A composite product as claimed in Claim 36 in which said thermoplastic binder and said particulate material of said substructure are recycled materials with said thermoplastic binder comprising from about 30%
to about 70% and said particulate material comprising from about 70% to about 30% by weight of said substructure.

38. A composite product as claimed in Claim 37 in which at least a portion of said particulate material is a fibrous material.

39. A composite product as claimed in Claims 37 or 38 in which said cover material comprises a plastic or metal sheeting.

40. A composite product as claimed in Claims 36 or 37 in which said cover material also covers the inner face of said door panel.

41. A composite product as claimed in Claim 14 in which said thermoplastic binder and said particulate material of said substructure are recycled materials with said thermoplastic binder comprising from about 30%
to about 70% and said particulate material comprising from about 70% to about 30% by weight of said substructure and said cover material comprises an encompassing sheath of material surrounding said substructure.