1 As originally filed Extruded plastics profiles comprising continuously introduced insulation elements 5 Description The present invention relates to a continuous process for producing a profile compris ing at least one core made of a polyurethane foam or a mixture comprising a polyure thane foam, at least one jacket made of at least one thermoplastic material, and op 10 tionally at least one foil between core and jacket, to a profile produced via said process, to the use of this profile for producing windowframes, doorframes, or in the fitting-out of interiors, or in apparatuses in which, during operation, temperature differences arise between interior space and exterior space, and also to an apparatus for carrying out the process of the invention. 15 The process of the invention can produce profiles from which windowframes or door frames can be produced for house construction. Within the prior art there are known processes for producing similar profiles and, re 20 spectively, windowframes or doorframes. DE 28 44 006 Al discloses a process for extruding plastics profiles which have a core made of foamed plastic enclosed on all sides by a jacket made of a plastic, where, in a single operation, the material for the jacket is introduced into the extruder die system, 25 and at the same time the core material is introduced into the cavity of the shaped jack et, where gases introduced into the cavity of the jacket during the foaming of the core material are dissipated by way of the extruder die system. A problem with this process is that, although the gases generated are dissipated, the foam obtained in the profile is not particularly uniform. Another disadvantage of this process is that the reactive sys 30 tem for the foamed plastic has to be passed through the hot extruder die system, with disadvantages in terms of energy and of process technology. WO 99/16996 Al discloses a process for producing frame profiles for windows or doors, where the outer profile is first produced from a thermoplastic and then a foama 35 ble mixture based on a polyurethane is introduced into the profile, and when the mix ture is foamed to fill the available space a strong adhesive bond is generated between exterior profile and foam. This document also discloses a process where a prefabricat ed, fully foamed core is inserted into the pre-shaped exterior profile. 40 DE 199 61 306 Al likewise discloses a process for producing a profile via extrusion. This profile comprises an exterior shell and a foamed interior core. In this process, the exterior shell of the profile is first extruded, and then a foamable material is foamed to fill the available space.
2 DE 1 959 464 likewise discloses a process for continuously extruding continuous pro files with a jacket made of thermoplastic and with a foam core, where the jacket made of thermoplastic is first produced via extrusion and a foamable material is then used to 5 fill the available space therein. The process of DE 1 779 271 produces a flexible plastics profile strip by using extru sion to produce the flexible exterior sheath and the foamed core simultaneously. 10 US 2006/0255488 Al likewise discloses a process for producing plastics profiles which have a foamed core, via simultaneous extrusion of the two materials, respectively in the molten state. EP 2 072 743 A2 discloses a process for foaming to fill the available space in a hollow 15 windowframe or hollow doorframe. For this, plastics profiles produced via extrusion are assembled to give finished windowframes or finished doorframes, and a foamable ma terial is then introduced to fill the available space. The prior art also discloses processes for producing these profiles having a foamed 20 core where fully foamed inserts are inserted into the extruded profiles, see by way of example DE 202009003392 U1 or WO 02/090703 A2. An example of a disadvantage of the processes mentioned from the prior art is that plastics profiles are produced via melt extrusion and then after a short time a foamable 25 material has to be inserted into these profiles. The profiles are therefore still hot or at least warm, and this has an adverse effect on the filling of the available space by foamable material introduced. Furthermore, when foaming fills the available space of one chamber of the plastics profile in a continuous process it is possible to produce only profiles with one, and no more than one, chamber comprising foam, since the 30 lance through which the reactive system is introduced has to be introduced into the profile. Another disadvantage is that the reactive polyurethane system has to be passed through the hot extruder die system. In the light of the prior art, it is an object of the present invention to provide a continu 35 ous process which can produce profiles comprising at least one core made of a foamed material and one jacket made of a thermoplastic material, where a feature of the pro cess is that it provides access to appropriate profiles which feature particularly uniform and homogeneous distribution of the foam within the profile chamber intended for that purpose. The foaming in the process is moreover intended to take place under condi 40 tions which permit ideal development of the foam. The process is moreover intended to 3 permit avoidance of complicated process technology for the individual precursor com pounds for jacket or core. The invention achieves these objects via a continuous process for producing a profile 5 comprising at least one core made of a polyurethane foam or a mixture comprising a polyurethane foam, one jacket made of at least one thermoplastic material, and option ally at least one foil between core and jacket, comprising at least the steps of: (A) optionally introducing a foil into a gripper-belt system which has the shape of the 10 profile, (B) introducing at least one liquid, foamable reactive system of the core comprising a polyisocyanate a) and at least one higher molecular compound having groups reactive towards isocyanate groups into the gripper-belt system in such a way 15 that any foil present at least to some extent encloses the reactive mixture, (C) shaping of the core in the gripper-belt system, (D) optionally cooling the core from step (C), 20 (E) introducing the core from step (C) or (D) into an extruder with attached extrusion die for producing hollow profiles, in order to sheath the core with a jacket made of at least one thermoplastic material and thus obtain the profile, 25 (F) optionally cooling the profile from step (E), and (G) optional cutting of the profile from step (E) or (F). The process of the invention serves for producing a profile comprising at least one core 30 made of a polyurethane foam or a mixture comprising a polyurethane foam, at least one jacket made of at least one thermoplastic material, and optionally at least one foil between core and jacket. The profile produced in the invention comprises at least one core made of a polyure 35 thane foam or a mixture comprising a polyurethane foam. In one particularly preferred embodiment, the at least one foamed material located in the core is a polyurethane foam. 40 Polyurethanes, in particular in foamed form, are known per se to the person skilled in the art, and are described by way of example in DE 10 124 333.
4 In the invention, it is particularly preferable to use rigid polyurethane foams in the core of the profile of the invention. The polyurethane foam or the mixture comprising a polyurethane foam according to the 5 present invention is obtained according to the present invention from a liquid reactive system comprising at least one polyisocyanate a) and at least one higher molecular compound having groups reactive towards isocyanate groups b). In contrast to the processes known from the prior art in the process according to the 10 present invention, not a readily polymerized material is introduced into the gripper-belt or the foil and foamed but a liquid reactive system, comprising the starting compounds for the preparation of polyurethane foams, i. e. at least one polyisocyanate a) and at least one higher molecular compound having groups being reactive towards isocyanate groups b), is introduced and the polymerization reaction for forming the polymeric poly 15 urethanes and the foaming for preparation of the foam take place, preferably at the same time. Polyurethane foams, in particular rigid polyurethane foams, have been known for a long time and are widely described in the literature. They are usually produced via re 20 action of organic polyisocyanates a) with compounds b1) having at least two groups reactive toward isocyanate groups, mostly polyols and/or polyamines. The at least one higher molecular compound having groups reactive towards isocyanate groups b) is according to the present invention preferably a compound having at least two groups reactive towards isocyanate groups b1). 25 Organic polyisocyanates a) that can be used are preferably aromatic polyfunctional isocyanates. Individual examples that may be mentioned are tolylene 2,4- and 2,6-diisocyanate 30 (TDI) and the corresponding isomer mixtures, diphenylmethane 4,4'-, 2,4'-, and 2,2' diisocyanate (MDI) and the corresponding isomer mixtures, mixtures made of diphenyl methane 4,4' and 2,4'-diisocyanates, polyphenyl polymethylene polyisocyanates, mix tures made of diphenylmethane 4,4'-, 2,4'-, and 2,2'-diisocyanates, and of polyphenyl polymethylene polyisocyanates (crude MDI), and mixtures made of crude MD[ and of 35 tolylene diisocyanates. The organic di- and polyisocyanates can be used individually or in the form of mixtures. Other materials often used are those known as modified polyfunctional isocyanates, i.e. products which are obtained via chemical reaction of organic di- and/or polyisocya 40 nates. Examples that may be mentioned are di- and/or polyisocyanates comprising 5 isocyanurate groups and/or comprising urethane groups. The modified polyisocyanates can optionally be mixed with one another or with unmodified organic polyisocyanates, e.g. diphenylmethane 2,4'- and/or 4,4'-diisocyanate, crude MDI, and/or tolylene 2,4 and/or 2,6-diisocyanate. 5 Materials that can also be used alongside these are reaction products of polyfunctional isocyanates with polyfunctional polyols so called polyisocyanate prepolymers, and also mixtures of these with other di- and polyisocyanates. 10 The polyisocyanate component a) is preferably introduced in the form of polyisocya nate prepolymers. These polyisocyanate prepolymers are obtainable by reaction of the above-mentioned polyisocyanates with polyols to obtain the prepolymer, for example at a temperature of 30 to 100 *C, preferably at about 80 "C. In a preferred embodiment, 4,4'-MD is used with uretone imine modified MDI and commercially available polyols 15 based on polyesters, for example on adipic acid, polyethers, for example based on ethylene oxide and/or propylene oxide or polytetrahydrofurane (PTHF) or polycarbona tols, for example as mentioned in European patent application EP 3007101407.0, are used for the preparation of prepolymers according to the present invention. 20 Polyols are known to the skilled artisan and are described for example in "Kun ststoffhandbuch, Band 7, Polyurethane" Carl Hanser Verlag, 3. Auflage 1993, Kapitel 3.1. Prepolymers on ether basis are preferably obtained by reaction of polyisocyanates, particularly preferably 4,4'-MDI, with bi- to three-functional polyoxipropylene- and/or polyoxipropylene-polyoxyethylene polyols. Their preparation is usually conducted by 25 the known basically catalyzed addition of propylene oxide alone, in mixture with eth ylene oxide or blockwise to H-functional, preferably OH-functional starting compounds. Starting compounds are for example water, ethylene glycols or propylene glycols or glycerine or trimethylol propane. Further, as catalysts multimetal cyanide compounds, so called DMC-catalysts, can be used. Furthermore, catalysts of Lewis-acids, like 30 bortrifluoride, can be used. Preferably polyethers are used as polyol, as mentioned under b) in the following. When ethylene oxide-/propylene oxide mixtures are used, ethylene oxide is used in an amount of 10 to 50 % by weight, in respect of the total amount of alkylene oxide. The 35 integration of alkylene oxides can take place blockwise or as a statistical mixture. Par ticularly preferred is addition of an ethylene oxide- and endcap ("EO-cap") in order to increase the amount of more reactive primary OH-end groups. The number average molecular weight of the polyols is preferably between 400 and 4500 g/mol.
6 A material that has proven particularly successful as organic polyisocyanate is crude MDI having from 29 to 33% by weight NCO content and having a viscosity at 25'C in the range from 150 to 1000 mPa-s. 5 As higher molecular compounds with groups reactive towards isocyanate groups b), preferably as compounds bi) which have at least two groups reactive towards isocya nate are in particular polyether alcohols and/or polyester alcohols, and/or polycar bonate alcohols having OH numbers in the range from 100 to 1200 mg KOH/g. 10 In a preferred embodiment according to the present invention mixtures comprising pol yetherols and polyesterols are used as higher molecular compounds b). Higher molecular compounds b) with groups reactive towards isocyanate groups have preferably a molecular weight of more than 400 g/mol according to the present inven 15 tion, preferably, the molecular weight is higher than 550 g/mol. The average functionali ty of the higher molecular compounds with groups reactive towards isocyanate groups is preferably less than 2.5. The polyester alcohols are mostly produced via condensation of polyhydric alcohols, 20 preferably diols, having from 2 to 12 carbon atoms, preferably from 2 to 6 carbon at oms, with polybasic carboxylic acids having from 2 to 12 carbon atoms, e.g. succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, decanedicar boxylic acid, maleic acid, fumaric acid, and preferably phthalic acid, isophthalic acid, terephthalic acid, and the isomeric naphthalenedicarboxylic acids. 25 The dicarboxylic acids can be used separately or as a mixture among one another. Instead of the free dicarboxylic acids, the corresponding dicarboxylic acid derivatives, for example dicarboxylic esters of alcohols with one to four carbon atoms or dicarbox ylic acid anhydrides can be used. Preferably, dicarboxylic acid mixtures of succinic-, 30 glutaric- and adipic acid in proportions of for example 20 to 35 : 35 to 50 : 20 to 32 : 35 to 50 : 20 to 32 parts by weight, and preferably adipic acid. Examples of 2 and more valent alcohols, preferably diols are: ethane diol, diethylene glycol, 1,2- or 1,3-propane diol, dipropylene glycol, 1,4-butane diol, 1,5-pentane diol, 1,6-hexane diol, 1,10-decane diol, glycerine and trimethylol propane. Preferably, ethan diol, diethylene glycole, 1,4 35 butane diole, 1,5-pentane diol and 1,6-hexane diole are used. Moreover, polyester pol yols of lactones, for example epsilon-caprolactone or hydroxycarboxylic acids, for ex ample omega-hydroxycaproic acids, can be used. For the preparation of polyester polyols, organic, for example aromatic and preferably 40 aliphatic polycarboxylic acids and/or derivatives and polyvalent alcohols can be poly- 7 condensed without a catalyst or preferably in the presence of esterification catalyst, advantageously in an atmosphere of inert gas, for example nitrogen, carbon monoxide, helium, argon and others, in melt at temperatures of 150 to 250 0C, preferably 180 to 220 0C, optionally under decreased pressure, up to a desired acid number, which is 5 preferably lower than 10, particularly preferably lower than 2. According to a preferred embodiment, the esterification mixture is polycondensed at above-mentioned tempera tures up to an acid number of 80 to 30, preferably 40 to 30, under normal pressure and subsequently under a pressure of less than 500 mbar, preferably 50 to 150 mbar. Iron-, cadmium-, cobalt-, lead-, zinc-, antimony-, magnesium-, titanium- and tin-catalysts in 10 the form of metals, metal oxides or metal salts can be used as esterification catalysts. The polycondensation can also be conducted in liquid phase in the presence of dillu tion- and/or entrainers, for example benzene, toluene, xylene or chlorobenzene for aci otropic distillation of the condensation water. For the preparation of polyester polyols, organic polycarboxylic acids and/or derivatives and polyvalent alcohols are advanta 15 geously polycondensated in a molar ratio of 1 : 1 to 1.8, preferably 1 : 1.05 to 1.2. The polyester polyols obtained advantageously have a functionality of 1.8 to 4, particu larly preferably of 1.9 to 3 and particularly of 2.0 to 2.5 and a molecular weight of 480 to 5000, preferably 1000 to 4500 g/mol and preferably 1600 to 4500. 20 The functionality of the preferred polyether used in the invention is preferably from 2 to 8, in particular from 3 to 8. In particular, it is possible to use polyether polyols blH) which are produced by known 25 processes, for example via anionic polymerization of alkylene oxides in the presence of catalysts, preferably alkali metal hydroxides, amines, or what are known as DMC cata lysts. Alkylene oxides mostly used are ethylene oxide and/or propylene oxide, preferably 30 pure propylene 1,2-oxide. Particular starter molecules that are used are compounds having at least 3, preferably from 4 to 8, hydroxy groups, or having at least two primary amino groups in the mole cule. 35 Starter molecules which are used having at least 3, preferably from 4 to 8, hydroxy groups in the molecule are preferably trimethylolpropane, glycerol, toluenediamine, pentaerythritol, sugar compounds, such as glucose, sorbitol, mannitol, and sucrose, polyhydric phenols, resols, e.g. oligomeric condensates derived from phenol and for- 8 maldehyde, and Mannich condensates derived from phenols, formaldehyde, and from dialkanolamines, and also melamine. Starter molecules used having at least two primary amino groups in the molecule are 5 preferably aromatic di- and/or polyamines, e.g. phenylenediamines, tolylene-2,3-, 2,4-, 3,4-, and 2,6-diamine, and 4,4'-, 2,4'-, and 2,2'-diaminodiphenylmethane, and also ali phatic di- and polyamines, such as ethylenediamine. The functionality of the polyether polyols is preferably from 3 to 8, and their hydroxy 10 numbers are preferably from 100 mg KOH/g to 1200 mg KOH/g, and in particular from 240 mg KOH/g to 570 mg KOH/g. Among the compounds b1) having at least two hydrogen atoms reactive toward isocy anate are also the optionally concomitantly used chain extenders and crosslinking 15 agents. It can prove advantageous for modification of mechanical properties to add difunctional chain extenders, crosslinking agents of functionality 3 or higher, or else optionally mixtures thereof. Chain extenders and/or crosslinking agents used are pref erably alkanolamines and in particular diols and/or trials having molecular weights smaller than 400, preferably from 60 to 300. 20 The amount advantageously used of chain extenders, crosslinking agents, or mixtures thereof is from 1 to 20% by weight, preferably from 2 to 5% by weight, based on polyol component b1). 25 Further information concerning the polyether alcohols and polyester alcohols used, and also production of these, is found by way of example in Kunststoffhandbuch [Plastics handbook], volume 7 "Polyurethane" [Polyurethanes], edited by GUnter Oertel, Carl Hanser-Verlag, Munich, 3 d edition, 1993, pages 57 to 74. 30 In an embodiment to which preference is further given, within the polyurethanes that are present in the invention within the core of the profile of the invention, there are fur ther additives present, for example selected from the group consisting of flame retard ants, surfactant substances, foam stabilizers, cell regulators, fillers, pigments, dyes, flame retardants, hydrolysis stabilizers, antistatic agents, agents having fungistatic and 35 bacteriostatic effect, and mixtures thereof. Flame retardants that can be used are organic phosphoric and or phosphonic esters. It is preferable to use compounds that are not reactive toward isocyanate groups. Among the preferred compounds are also phosphoric esters comprising chlorine. Typical rep- 9 resentatives of this group of flame retardants are triethyl phosphate, diphenyl cresyl phosphate, tris(chloropropyl) phosphate, and also diethyl ethanephosphonate. Alongside these, flame retardants comprising bromine can also be used. Flame retard 5 ants used comprising bromine are preferably compounds having groups reactive to ward the isocyanate group. Compounds of this type are esters of tetrabromophthalic acid with aliphatic diols and alkoxylation products of dibromobutenediol. It is also pos sible to use compounds which derive from the group of the brominated neopentyl com pounds comprising OH groups. 10 For production of the polyurethanes preferably used in the invention in the core of the profile of the invention it is usual to use blowing agents, catalysts, and cell stabilizers, and also, if necessary, further auxiliaries and/or additives. 15 Water can be used as blowing agent, and reacts with isocyanate groups with elimina tion of carbon dioxide. It is also possible to use what are known as physical blowing agents in combination with, or instead of, water. These are compounds which are inert toward the starting components and which are mostly liquid at room temperature, and which evaporate under the conditions of the urethane reaction. The boiling point of said 20 compounds is preferably below 50"C. Among the physical blowing agents are also compounds which are gaseous at room temperature and which are introduced under pressure into the starting components or are dissolved therein, examples being carbon dioxide, low-boiling-point alkanes, and fluoroalkanes. 25 The compounds are mostly selected from the group consisting of alkanes and/or cyclo alkanes having at least 4 carbon atoms, dialkyl ethers, esters, ketones, acetals, fluoro alkanes having from 1 to 8 carbon atoms, and tetraalkylsilanes having from 1 to 3 car bon atoms in the alkyl chain, in particular tetramethylsilane. 30 Examples that may be mentioned are propane, n-butane, iso- and cyclobutane, n-, iso-, and cyclopentane, cyclohexane, dimethyl ether, methyl ethyl ether, methyl butyl ether, methyl formate, acetone, and also fluoroalkanes which can be degraded in the tropo sphere and are not therefore hazardous to the ozone layer, e.g. trifluoromethane, difluoromethane, 1,1,1,3,3-pentafluorobutane, 1,1,1,3,3-pentafluoropropane, 1,1,1,2 35 tetrafluoroethane, difluoroethane, and heptafluoropropane; fluoroalkenes can also be used. The physical blowing agents mentioned can be used alone or in any desired combinations with one another. Catalysts used are in particular compounds which greatly accelerate the reaction of the 40 isocyanate groups with the groups reactive toward isocyanate groups. Examples of 10 these catalysts are strongly basic amines, e.g. secondary aliphatic amines, imidazoles, amidines, and also alkanolamines. If the intention is to incorporate isocyanurate groups into the polyurethane foam, specif 5 ic catalysts are required. Usual isocyanurate catalysts used are metal carboxylates, in particular potassium acetate and solutions thereof. As a function of requirement, the catalysts can be used alone or in any desired mix tures with one another. 10 Further additives used are the substances known per se for this purpose, for example surfactant substances, foam stabilizers, cell regulators, fillers, pigments, dyes, flame retardants, hydrolysis stabilizers, antistatic agents, agents having fungistatic and bacte riostatic effect. 15 More detailed information concerning a process for producing the polyurethanes pref erably used in the invention, and also concerning the starting materials, blowing agents, and catalysts used, and also auxiliaries and/or additives is found by way of example in Kunststoffhandbuch [Plastics handbook], volume 7 "Polyurethane" [Polyure 20 thanes], Carl-Hanser-Verlag, Munich, 1" edition, 1966, 2 nd edition, 1983 and 3 rd edition, 1993, pages 104 to 192. To produce the rigid polyurethane foams, the polyisocyanates a) and polyol component b) are reacted in amounts such that the isocyanate index is from 90 to 220, preferably 25 from 100 to 200, in particular from 110 to 190. The density of the rigid polyurethane foams preferably used in the invention is prefera bly from 10 to 400 kg/m3 particularly preferably from 20 to 200 kg/m 3 , very particularly preferably from 30 to 100 kg/m 3 . 30 Details of the production of the polyurethane foams according to the invention are specified in steps (B) and (C). The core of the profile of the invention can generally have any desired shape which 35 appears to the person skilled in the art to be suitable for the desired application. The cross-sectional shape of the core can be round and/or angular. The core can moreover be of uniform or nonuniform shape and by way of example can have cavities, grooves, ridges, etc., where these profiling effects can run either parallel to or perpendicularly to the direction of production. In one preferred embodiment, the core shaped in step (C) 40 of the process of the invention provides the shape of the profile to be produced or, re- 11 spectively, provides the region enclosed by the insulating element. In another embodi ment of the profile produced in the invention, for example in the case of a window pro file, the core produced in the invention is sheathed by a jacket to which fillets have been bonded, onto which further fillets are then optionally bonded. The entirety made 5 of core, jacket, and fillets forms the resultant profile of the invention. The shape of the core is in turn prescribed via the shape of the gripper-belt system used in the invention. The dimensions of the core are generally from 5 to 250 mm, preferably from 10 to 150 mm, particularly preferably from 20 to 100 mm, in particular 10 from 25 to 80 mm, and in the case of nonuniformly shaped cores these dimensions describe the greatest available distances in one direction. The profile produced in the invention comprises at least one core made of a polyure thane foam or a mixture comprising a polyurethane foam. In one preferred embodi 15 ment, the profile produced in the invention comprises precisely one core made of a polyurethane foam or a mixture comprising a polyurethane foam. It is also possible in the invention that the profile has two, three or fore cores made of a polyurethane foam or a mixture comprising a polyurethane foam. If there are two, three, or four cores pre sent in the profile produced in the invention, these can have identical or different 20 shapes. The profile produced in the invention comprises, alongside the at least one core, at least one jacket made of at least one thermoplastic material. The term "jacket" in the invention means a coating of the core of the profile of the invention. The jacket here 25 encloses the core to some extent or entirely, preferably entirely. In one preferred em bodiment, the jacket moreover has fillets bonded thereto. The thickness of the jacket per se or of the jacket and of the optionally present fillets of the jacket is generally from 1 to 20 mm, preferably from 2 to 15 mm, particularly prefer 30 ably from 3 to 10 mm, and the thicknesses of the jacket and of the fillets here can be different or identical. In one preferred embodiment, the jacket or the fillets has/have various thicknesses at various sites on the profile, where the thicknesses are identical in a longitudinal direction but can be different in a transverse direction. This is a func tion by way of example of the shape of the profile, which in turn is a function of the 35 subsequent application. The jacket of the profile to be produced in the invention generally comprises at least one thermoplastic material. Suitable thermoplastic materials are known per se to the person skilled in the art and by way of example are those selected from the group con 40 sisting of polyolefins, by way of example acrylonitrile-butadiene-styrene (ABS), polyme- 12 thyl methacrylate (PMMA), polyethylene (PE), polypropylene (PP), polystyrene (PS), or polyvinyl chloride (PVC), polycondensates, such as polyamides (PA), e.g. PA 6 or PA 6,6, polylactate (PLA), polycarbonates (PC), polyesters, such as polyethylene ter ephthalate (PET), polyether ether ketone (PEEK), polyadducts, such as thermoplastic 5 polyurethane, wood-plastics composites, and mixtures thereof. In a particularly pre ferred embodiment, the jcket of the profile to be produced in the invention comprises polyvinyl chloride (PVC). Polyvinyl chloride (PVC) and its preparation by polymerization of vinyl chloride is known per se to the person skilled in the art. 10 In one preferred embodiment, the jacket comprises a thermoplastic material which has a melting point below 220*C. In the profile produced in the invention, there is optionally at least one foil between core and jacket. The term "foil" in the invention means a layer or coating optionally present 15 between core and jacket in the profile produced in the invention. Said foil can generally be composed of any material which appears to the person skilled in the art to be suita ble for the profile of the invention. In one preferred embodiment, the foil optionally present between core and jacket com 20 prises a material selected from the group consisting of thermoplastic polyurethane, polyolefins, such as polyethylene, polypropylene, polystyrene, polyvinyl chloride, and/or paper, paperboard, textiles, nonwovens, Teflon, metal, metal-plastics composite mate rials, and mixtures thereof. The materials mentioned, and processes for producing same, are known per se to the person skilled in the art. The invention can also use a 25 foil which is composed of more than one material, the term used being composite ma terials. In one particularly preferred embodiment, the foil comprises Teflon between core and jacket of the profile produced in the invention, and it is very particularly preferable that 30 the foil is composed of Teflon. In this embodiment, the foil present prevents permanent adhesion of the core to the jacket, in such a way that articles produced from the profile produced in the invention, for example windowframes or doorframes, can easily be recycled after use, because the different plastics, for example polyurethane foam of the core and polyvinyl chloride of the jacket, can easily be separated from one another. 35 In another preferred embodiment, the foil comprises a thermoplastic polyurethane. The result is particularly strong adhesion of the foil to the core. Another result is particularly good adhesion of the foil to the jacket, the overall result therefore being particularly good and strong adhesion of the three components to one another, and a particularly 40 stable profile. Thermoplastic polyurethanes preferably used are by way of example 13 composed mainly of MDI and PTHF polyols, for example as described in DE 10234007. In another preferred embodiment, the foil comprises a metal or a metal-plastics com 5 posite material, by way of example described in DE 10211274. In said embodiment, there is a gastight sheath around the core, which preferably comprises a polyurethane foam. It is thus possible in the invention that blowing agent, in particular pentane, pre sent in the foam cannot escape by evaporation from the core. The core therefore also retains its low lambda value over a very long period, and the insulating effect of the 10 core or of the entire profile therefore remains in essence constant over a long period. The thickness of the foil which is optionally present between core and jacket is by way of example from 10 to 3000 pm, preferably from 25 to 1000 pm, particularly preferably from 50 to 750 pm, in particular from 100 to 500 pm. 15 A detailed explanation is provided below of the individual steps of the continuous pro cess of the invention: Step (A): 20 The optional step (A) of the process of the invention comprises introducing a foil into a gripper-belt system which has the shape of the profile. Step (A) of the process of the invention is carried out if a foil is to be present between 25 the core and the jacket of the profile to be produced. The invention preferably provides said foil in the form of a roll and introduces it by means of an unwind apparatus or, re spectively, conveying apparatus known to the person skilled in the art into the actual apparatus for producing the profile. 30 In step (A), the foil is introduced into a gripper-belt system known to the person skilled in the art. It is essential to the invention here that said gripper-belt system has the shape of the profile to be produced. Figures 2, 3 and 4 depict possible embodiments of said gripper-belt system in the invention. 35 A gripper-belt system with an appropriate number of elements is provided in step (A), designed appropriately for the number of cores to be comprised in the profile to be pro duced. If there is one core present in the profile to be produced, a gripper-belt system with two elements is preferably suitable. If there are two cores present in the profile to be produced, a gripper-belt system with three elements is used. If there are three cores 40 present in the profile to be produced, it is preferable to use a gripper-belt system with 14 four elements. If there are four cores present in the profile to be produced, it is prefera ble to use a gripper-belt system with five elements. If more than one core is present in the profile to be produced in the invention, these can have been arranged within the profile so as to be alongside one another and/or mutually superposed. The known con 5 tinuous processes cannot produce a profile of this type with two or four cores. The gripper-belt system used in the invention is known per se to the person skilled in the art and is described by way of example in DE 102004023881. 10 in step (A) of the process of the invention, the foil is introduced into the gripper-belt system in such a way that it preferably lies on the floor of the gripper-belt system and, on the sides of the gripper-belt system, is conducted as far as the upper edge. In one preferred embodiment, the dimensions of the foil are such that it overlaps the upper edge of the gripper-belt system and, by virtue of the temperature prevailing in the grip 15 per-belt system, to the extent that the temperature of the gripper-belt system or the temperature of the reacting PU foam is above the Tg or the Tm of the foil used, fuses to itself in such a way that the foil introduced forms a tube, where the shape of the tube is preferably exactly that prescribed by the gripper-belt system for the profile to be pro duced. 20 In another preferred embodiment, step (A) is carried out in such a way that when the foil is introduced into the gripper-belt system the jaws have not yet been closed com pletely. This embodiment makes it easier to introduce the foil and permits crease-free introduction. 25 It is preferable to introduce the foil into the gripper-belt system by way of a shaping apparatus, preferably a forming shoulder. Step (A) of the process of the invention is preferably carried out at a temperature from 30 room temperature to 40*C, particularly preferably from room temperature to 30*C. Step (B): Step (B) of the process of the invention comprises introducing at least one liquid foam 35 able reactive system of the core comprising at least one polyisocyanate a) and at least one higher molecular compound with groups reactive against isocyanate groups b) into the gripper-belt system, so that any optionally present foil at least to some extent en closes the precursor material. In the invention, a reactive system means a mixture of precursor compounds for the foamed material present in the core. 40 15 Step (B) of the process of the invention uses apparatuses known to the person skilled in the art to introduce the material. According to the present invention the components needed for producing the polyurethane foam, in particular a polyisocyanate component and a polyol component, and also the other components mentioned at an earlier stage 5 above are introduced. In one particularly preferred embodiment, the method for step (B) introduces a mixture comprising the diisocyanate component and the polyol com ponent. The mixture is produced from the individual substances in mixing equipment known to the person skilled in the art. By way of example, the catalysts and the blowing agents are metered into the polyol component by way of further metering pumps. 10 In one particularly preferred embodiment, in which step (A) of the process of the inven tion has been carried out, at least one liquid foamable reactive system of the core is charged in step (B) into the foil introduced in step (A), and it is preferable here that the foil has formed a tube in step (A) or forms a tube in step (B). The amount of the precur 15 sor material to be charged here is judged by the person skilled in the art in such a way that, after foaming, the entire space available for the core has been filled with polyure thane foam. If step (A) of the process of the invention is not carried out, it is preferable that the grip 20 per-belt system is provided with a release agent before charging of the precursor mate rial in step (B) of the process of the invention, Any of the blowing agents known to the person skilled in the art is generally suitable, and silicones or waxes are particularly suitable. 25 Step (B) of the process of the invention is preferably carried out at room temperature, and the temperatures of the starting components for polyurethane production here are those known to the person skilled in the art. 30 Step (C): Step (C) of the process of the invention comprises the shaping of the core in the grip per-belt system. 35 The invention preferably carries out step (C) in such a way that the foamable precursor material introduced in step (B) is foamed in the gripper-belt system. The precursor ma terial here, or the core being formed here, is preferably transported via the movement of the gripper-belt system. In a further preferred embodiment, a train unit, for example two motor-powered wheel systems, are present after the gripper-belt system, that pull 40 the foil, preferably at start, through the gripper-belt system. In a further preferred em- 16 bodiment, preferably after start, i. e. when the process is running in a stable way, the cured hart foam profile which is surrounded with foil, is transported by a train unit, for example two motor-powered wheel systems. 5 By virtue of the pressure conditions and temperature conditions prevailing in the grip per-belt system, the precursor materials present, in particular the polyisocyanate com ponent and polyol component, react to give the desired foam. The shaping of the grip per-belt system, or of the foil present in the gripper-belt system, causes the foam to assume the shape of the desired profile during the foaming process. "Overfill", which is 10 a function of the amount introduced and of the free-foamed density, is used to obtain compaction, thus giving the foam high homogeneity and stability. Step (C) of the process of the invention is preferably carried out at a temperature from room temperature to 55'C, particularly preferably from room temperature to 45"C. 15 Any gases produced in step (C) during the shaping of the core are preferably not dissi pated in the invention, but instead remain within the material of the core. To this end, the amount of precursor material can preferably be judged by the person skilled in the art in such a way that, after the foaming process, the foam charged to the gripper-belt 20 system or to a foil present therein, or to a tube shaped therefrom, has a desired density and quality. The pressure at which step (C) of the process of the invention is generally carried out is from 0.8 to 1.2 bar (a), preferably from 0.9 to 1.1 bar (a), particularly preferably atmos 25 pheric pressure. Step (D): The optional step (D) of the process of the invention comprises the cooling of the core 30 from step (C). Step (D) of the process of the invention is carried out if the temperature of the core made of a polyurethane foam or a mixture comprising a polyurethane foam optionally at least to some extent sheathed by at least one foil is too high for the next step (E) of 35 the process of the invention. Cooling can be carried out by the processes known to the person skilled in the art. By way of example, the core just formed can be passed through an appropriate coolant, such as water or air. In one preferred embodiment, the optional step (D) of the process of the invention is carried out.
17 The temperature to which the core is preferably cooled in step (D) of the process of the invention is from room temperature to 700C, preferably from room temperature to 500C, Step (E): 5 Step (E) of the process of the invention comprises introducing the core from step (C) or (D) into an extruder with attached extrusion die for producing annular profiles, in order to sheath the core with a jacket made of at least one thermoplastic material, thus ob taining the profile. 10 In step (E), the core obtained in step (B) and optionally sheathed by a foil is introduced into an extruder which comprises a die which replicates the shape of the profile. In the extruder of step (E), the thermoplastic material which is to form the jacket is now ap plied in molten form to the core. Embodiments of this extruder used in the invention are 15 in general terms known to the person skilled in the art and are described by way of example in WO 2009/098068. Step (E) gives the profile of the invention comprising at least one core made of at least one foamed material, at least one jacket made of at least one thermoplastic material, 20 and optionally at least one foil between core and jacket. Step (E) of the process of the invention is preferably carried out at a temperature at which the thermoplastic material of the jacket is molten, for example from 100 to 2200C, particularly preferably from 130 to 1900C. 25 The prevailing temperature at which the thermoplastic material solidifies after leaving the extruder is preferably by way of example from 25 to 180*C, preferably from 50 to 1500C. 30 Extrusion of thermoplastic materials is known per se to the person skilled in the art and is described by way of example in "Einfohrung in die Kunststoffverarbeitung" [Introduc tion to plastics processing], 5 th edition, September 2006; pp. 87 - 180; Walter Michaeli; Hanser Fachbuchverlag. 35 The present invention also provides the process of the invention where, in step (E), reinforcement is introduced into the gripper-belt system or, respectively, into the extru sion die, i.e. into the profile-shaped die, of the extruder in such a way that said rein forcement system is present in the profile between core and jacket or in essence en tirely within the jacket. The presence of reinforcement in this type of profile is known 40 per se to the person skilled in the art. The reinforcement can be composed of any ma- 18 terial which appears to the person skilled in the art to be suitable. By way of example, the reinforcement introduced comprises at least one material selected from the group consisting of metals, such as aluminum or iron, plastics, such as polyesters, e.g. poly ethylene terephthalate or polybutylene terephthalate, glassfiber-reinforced plastics, and 5 mixtures thereof. Preference is given here to reinforcement made of plastic or of glass fiber-reinforced plastic. If reinforcement is introduced into the profile in the invention, this reinforcement can have its final shape when it is introduced into the extruder, an example being the shape 10 of a strip. In a second embodiment, the reinforcement is extruded in the extruder simul taneously with the jacket of the profile. To this end, the material of the reinforcement is introduced, preferably in the molten state, along the extruder. In one preferred embodiment of the invention, the dimensions of the reinforcement are 15 dependent on the dimensions of the profile and can maximize the stability of the rein forced profile. The design of this reinforcement gives reduced heat transmission within the profile, for example in windowframes or doorframes. Step (F): 20 The optional step (F) of the process of the invention comprises the cooling of the profile from step (E). This cooling can be carried out by processes known to the person skilled in the art, for example by passing the resultant profile through an appropriate coolant, such as air or water. 25 The temperature to which the profile is preferably cooled in step (F) of the process of the invention is from room temperature to 60*C, preferably from room temperature to 40'C, achieved by processes known to the person skilled in the art. 30 Step (G): The optional step (G) of the process of the invention comprises the cutting of the profile from step (E) or (F) of the process of the invention. Apparatuses for cutting the profile of step (G) are known in general terms to the person skilled in the art, an example be 35 ing sawing. The continuous process of the invention can in principle produce a contin uous profile, and this can therefore be cut in step (G) of the process of the invention into lengths suitable for the application, for example pieces of from 1 to 12 m, prefera bly from 2 to 8 m.
19 The invention can provide the resultant profiles with a coating. By way of example, this is necessary or useful when the plastic used for the jacket is not per se resistant to light and/or to weathering. The invention can use a coating based on acrylate or based on aliphatic polyurethane in order to obtain profiles that are resistant to light and/or to 5 weathering. The coating can be applied after production of the jacket, for example after step (E), (F), and/or (G). Processes and apparatuses for coating the jacket are known per se to the person skilled in the art. The present invention also provides the profile that can be produced via the process of 10 the invention. In relation to the details and to the preferred embodiments, see the statements relating to the process. The present invention also provides a profile comprising a core made of a polyurethane foam or a mixture comprising a polyurethane foam, a jacket made of at least one ther 15 moplastic material, and optionally a foil between core and jacket. In relation to the de tails and to the preferred embodiments, see the statements relating to the process. In one particularly preferred embodiment, the profile of the invention comprises a core made of a polyurethane foam, a jacket made of polyvinyl chloride (PVC), and a foil be 20 tween core and jacket made of thermoplastic polyurethanes, Teflon, metal, or a com posite material comprising metal, textile, and combinations thereof. It is further prefera ble that the profile of the invention comprises reinforcement, preferably made of the abovementioned materials, particularly preferably made of plastic or of glassfiber reinforced plastic. 25 In one preferred embodiment of the profile of the invention, the foil encloses the core at least to some extent, preferably entirely. In another preferred embodiment, the present invention therefore provides the profile of 30 the invention where the at least one foil comprises at least one material selected from the group consisting of thermoplastic polyurethanes, Teflon, metal, composite material comprising metal, textile, and combinations thereof. The present invention also provides the use of the profile of the invention for producing 35 windowframes, doorframes, or in the fitting-out of interiors, or in apparatuses in which, during operation, temperature differences arise between interior space and exterior space, examples being cold rooms, air-conditioning equipment, ventilation systems, refrigerators, (deep) freezer chests, or pool covers. The profiles of the invention are preferably used here for edging, or as profile for a space surrounded by a structure. 40 20 The present invention also provides an apparatus for carrying out the process of the invention, comprising a unit for introducing the liquid precursor material of the foamed core, optionally a unit for introducing a foil, a gripper-belt system, an extruder with at tached extrusion die for producing hollow profiles, and optionally units for cooling and 5 cutting. It is known that the individual elements of the apparatus of the invention are known to the person skilled in the art. 10 Figures Figure 1 shows an apparatus of the invention, where this is preferably used for carrying out the process of the invention. The meanings of the reference signs here are as fol lows: 15 1 Profile produced 2 Cooling unit 3 Extruder with profile-shaped die 5 Cooling zone 20 6 Feed vessel for polyol and optionally additives 7 Feed vessel for diisocyanate 8 Pump 1 9 Pump 2 10 Mixing unit 25 11 Foil 12 Unwind unit 13 Forming shoulder 14 Gripper-belt system 15 Saw 30 Figure 2 shows a gripper-belt system which can be used in the invention in order to produce a profile with a foam core. 16 and 17 here indicate the two jaws. Figure 3 shows a gripper-belt system which can be used in the invention for producing 35 a profile of the invention with two foam-element cores. Reference signs 18, 19 and 20 here indicate the three jaws of this gripper-belt system. A indicates the separation be tween the foam elements. Figure 4 shows two gripper-belt systems that are arranged one upon the other, where 40 reference signs 21, 22, 23 and 24 describe the single jaws. B describes the distance between the jaws of the gripper-belt.