Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
  • B29C70/04—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising reinforcements only, e.g. self-reinforcing plastics
  • B29C70/06—Fibrous reinforcements only
  • B29C70/08—Fibrous reinforcements only comprising combinations of different forms of fibrous reinforcements incorporated in matrix material, forming one or more layers, and with or without non-reinforced layers
  • B29C70/088—Fibrous reinforcements only comprising combinations of different forms of fibrous reinforcements incorporated in matrix material, forming one or more layers, and with or without non-reinforced layers and with one or more layers of non-plastics material or non-specified material, e.g. supports
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C33/00—Moulds or cores; Details thereof or accessories therefor
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C37/00—Component parts, details, accessories or auxiliary operations, not covered by group B29C33/00 or B29C35/00
  • B29C37/0025—Applying surface layers, e.g. coatings, decorative layers, printed layers, to articles during shaping, e.g. in-mould printing
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
  • B29C70/04—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising reinforcements only, e.g. self-reinforcing plastics
  • B29C70/06—Fibrous reinforcements only
  • B29C70/08—Fibrous reinforcements only comprising combinations of different forms of fibrous reinforcements incorporated in matrix material, forming one or more layers, and with or without non-reinforced layers
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
  • B29C70/04—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising reinforcements only, e.g. self-reinforcing plastics
  • B29C70/28—Shaping operations therefor
  • B29C70/40—Shaping or impregnating by compression not applied
  • B29C70/50—Shaping or impregnating by compression not applied for producing articles of indefinite length, e.g. prepregs, sheet moulding compounds [SMC] or cross moulding compounds [XMC]
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C43/00—Compression moulding, i.e. applying external pressure to flow the moulding material; Apparatus therefor
  • B29C43/32—Component parts, details or accessories; Auxiliary operations
  • B29C43/44—Compression means for making articles of indefinite length
  • B29C43/48—Endless belts
  • B29C2043/483—Endless belts cooperating with a second endless belt, i.e. double band presses
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T428/00—Stock material or miscellaneous articles
  • Y10T428/249921—Web or sheet containing structurally defined element or component
  • Y10T428/249953—Composite having voids in a component [e.g., porous, cellular, etc.]

Definitions

• the present invention relates to a method and a device for continuously manufacturing a composite plate comprising a thermoplastic or thermosetting matrix and reinforcing threads, and a layer of a coating improving the surface appearance, this plate being more particularly intended for the production of panels for vehicles or containers for transporting or storing goods.
• the invention relates to a method, and the device allowing its implementation, which consists in applying to a sheet of son deposited continuously on a moving substrate a powder of a material capable of reacting under the effect of heat to form a coating layer, said layer comprising at least one organic, thermoplastic or thermosetting material, and at least one reinforcing material, to be heated and then to compress the assembly thus obtained to form a composite plate.
• the walls of trucks, trailers and containers used for the transport or storage of goods are generally made up of panels made of a thermoplastic or thermosetting material integrating reinforcing wires, in particular glass, and a finishing layer which has for function of improving the appearance of the surface visible from the outside.
• the finishing layer makes it possible to reduce the “marking” effect linked to the presence of the reinforcing wires in the vicinity of the surface, in other words to make it smoother and possibly more shiny.
• the aesthetic aspect is not the only advantage provided by the layer: the surface condition being improved, it becomes easier to apply patterns and inscriptions, for example by means of a paint or in the form of a 'stickers, or to keep them clean.
• the walls of trucks, trailers and containers each consist of a single panel of large dimensions up to 3.5 meters wide and 17 meters long, or even more.
• a first method consists in forming a continuous strip from a matrix comprising reinforcing threads, in coating this strip with a film capable of forming the covering layer, and in cutting said strip to the dimensions required to form the composite panel. final.
• Obtaining wide panels requires having a film width at least equal to that of the panel. The production of such films is difficult and also very expensive because it requires machines specially adapted to these large widths.
• the film can be obtained and deposited directly by extrusion at the time of manufacture of the panel or the film already wound up can be obtained in the form of reels. For widths greater than 2 meters, it is not possible to proceed by extrusion because the cost of the machine is much too high.
• Another method is to cut the strip from the first method above to the dimensions of the panel, then apply the coating as paint.
• the nature of the material used does not allow the paint to hang properly by direct application. This is why it is generally recommended to treat the surface to be coated beforehand, for example by applying an adhesion primer or else by treatment using a flame ("flame") or by Corona effect. On the treated surface, it is generally applied a layer of a "filling" primer having the consistency of a putty and which serves to mask the surface irregularities. On the primer, possibly after a sanding step, the layer of paint is applied which forms the actual finishing layer.
• the object of the present invention is to provide a process which allows the rapid and continuous manufacture of composite plates having a coating improving the surface appearance which have large dimensions, in particular a large width.
• the present invention also aims to provide a method in which the coating is formed on the composite plate by application of a powder.
• a layer of threads in the form of a mat of continuous threads, a fabric, a knitted fabric or a set of non-interlaced continuous threads is continuously deposited on a moving substrate, this layer comprising at least one organic material and at least one reinforcing material
• a powder of an organic material capable of forming a coating layer under the action of heat is deposited on at least one face of said sheet.
• the tablecloth coated with the powder is heated to a temperature sufficient to melt the powder
• the sheet of wires is formed from at least one organic, thermoplastic or thermosetting material, forming the matrix and from at least one material capable of reinforcing said matrix.
• thermoplastic materials such as polyolefins, for example polyethylene and polypropylene, polyesters, for example polyethylene terephthalate (PET) and polybutylene terephthalate (PBT), polyamides, for example polyamides 6, 6, 6, 11 or 12, polyvinyl chloride (PVC) or acrylic homopolymers or copolymers, and thermosetting materials such as epoxy resins, unsaturated polyester resins, polyvinyl esters or phenolic resins .
• PET polyethylene terephthalate
• PBT polybutylene terephthalate
• PVC polyvinyl chloride
• thermosetting materials such as epoxy resins, unsaturated polyester resins, polyvinyl esters or phenolic resins .
• the reinforcing material can be any type of material capable of being obtained in the form of wires, for example glass, carbon or aramid.
• the sheet consists of a reinforcing material, advantageously glass, and one or possibly several thermoplastic organic materials, advantageously polyethylene, polypropylene, a polyester (PET, PBT) or a polyamide, or thermosetting, advantageously an epoxy resin, an unsaturated polyester resin, a polyvinyl ester or a phenolic resin.
• the sheet is made up of glass and organic matter (s) thermoplastic (s).
• the sheet generally comprises between 20 and 90% by weight of reinforcing material, preferably in the form of glass, preferably between 30 and 85% and in a particularly preferred manner between 40 and 80% by weight of reinforcing material. It may consist for all or part of son of thermoplastic material and son of reinforcing material, these son preferably being arranged alternately in the web and advantageously being intimately mixed.
• the ply may also include mixed threads obtained by the simultaneous gathering and winding of the threads or filaments of one of the organic thermoplastic and reinforcing materials, these mixed threads being able to be mixed with threads consisting solely of an organic thermoplastic material and / or a reinforcing material.
• the sheet can also be made up of all or part of the son of reinforcing material coated with thermosetting organic material.
• the ply comprises at least 50%, advantageously at least 80% and preferably 100% by weight of mixed yarns.
• co-mixed yarns are meant here yarns composed of glass filaments and filaments of thermoplastic organic material intimately mixed.
• These sons can be obtained by mechanical means described for example in patent US-A-4,818,318.
• the reinforcing threads and the thermoplastic threads are extracted from their respective windings, then the filaments which constitute them are separated in the form of two tablecloths of the same width. These layers are then brought into contact with each other to form a single layer, alternating as regularly as possible the two kinds of filaments, then the mixed filaments are combined into a single thread.
• mixed yarns is also meant the yarns which are directly obtained during the manufacture of organic thermoplastic filaments and glass filaments, for example as described in EP-A- 0 599 695 and EP-A- 0 616 055
• the filaments obtained by extrusion and mechanical drawing of a thermoplastic organic material in the molten state are thus drawn in the form of a sheet and are mixed with a bundle or a sheet of glass filaments (or are projected into said bundle or said sheet), said glass filaments also being drawn.
• These yarns are preferred because the distribution of the filaments is more regular than in the mixed yarns obtained in another way.
• the ply of threads is in the form of a mat of continuous threads, a fabric, a knitted fabric or a set of continuous non-interlaced threads, for example a grid or a knitted fabric warp with weft insertion.
• the ply may comprise one or more of the structures with continuous and organized threads mentioned above arranged in directions which can vary to a large extent, these structures being able moreover to be linked together by various methods, for example by needling, sewing-knitting by means of a tying or bonding wire.
• the ply is exclusively in the form of at least one fabric and / or knitted fabric and / or a set of non-interlaced continuous threads, formed at least in part from co-mixed threads.
• the fabrics falling within the scope of the invention comprise co-mixed threads which can be weft or warp threads, preferably both at the same time.
• the sheet of wires moving at a speed of, for example, between 0.5 and 10 m / min passes through a device allowing the application of the coating material in the form of a powder. Any known device which makes it possible to obtain a uniform distribution of the powder can be used. It is in particular possible to pass the sheet through a bed of powder whose height at the outlet is adjusted by means of a doctor blade allowing the deposition of a constant thickness of powder.
• a powdering device comprising one or more cylinders provided with grooves or pins, or an electrostatic device operating by spraying the powder onto the sheet and the powder particles being retained on the surface due to the difference in electrical potential.
• an electrostatic device operating by spraying the powder onto the sheet and the powder particles being retained on the surface due to the difference in electrical potential.
• the thickness of the powder layer is adjusted so as to obtain a coating on the final composite strip having a thickness of between 0.3 and 1 mm, preferably between 0.5 and 0.8 mm.
• the powder consists of particles of thermoplastic or thermosetting material, preferably having a high film-forming power. More preferably, the powder makes it possible to give the final coating sufficient opacity to make the reinforcing filaments invisible in the matrix.
• the thermoplastic material can be chosen from polyolefins, in the form of homopolymers such as polyethylene or polypropylene, or of copolymers, polyamides, polyesters and PVC.
• the thermosetting material is chosen from epoxy, polyesters, polyurethanes and phenolic compounds.
• the powder when the powder is applied directly to the sheet, without an intermediate structure as indicated below, it is of the same nature as the matrix.
• the powder may also comprise additives such as color pigments, anti-UV agents, anti-graffiti agents, agents making it possible to improve resistance to impact (gravel) and to scratches, anti-fouling agents, fireproofing agents.
• the total content of additives is generally less than 30% of the total weight of the powder, and preferably is less than 10%.
• the sheet of wires coated with the powder then passes into an area where it is heated to a temperature sufficient to allow the transformation of the sheet of wires into a matrix within which the reinforcing wires are embedded, and the melting of the powder into a coating film.
• the temperature must be higher than the melting temperature of the organic material having the highest melting point.
• the temperature must remain below the degradation temperature of the material with the lowest melting point.
• the degradation temperature is the temperature at which the material begins to be altered, this alteration can result in decomposition (inflammation), loss of integrity (creep) and / or change in color (yellowing).
• the heating temperature can be of the order of 100 to 300 ° C, in particular of the order of 200 to 220 ° C when the sheet is made of glass and polypropylene and the coating is polypropylene base.
• Heating can be done in several ways, for example using a radiating device of the infrared type such as an oven, panels or lamps, using a device for blowing air. hot such as a forced convection oven, using a contact heating device such as heated cylinders, or even using a double-strip laminating machine. Heating can combine several of the aforementioned means.
• a radiating device of the infrared type such as an oven, panels or lamps
• a device for blowing air hot such as a forced convection oven, using a contact heating device such as heated cylinders, or even using a double-strip laminating machine. Heating can combine several of the aforementioned means.
• a consolidation step which consists in subjecting the assembly formed to compression in an appropriate device, for example a calender with two cylinders.
• the force applied depends on the nature of the ply yarns and on the rheology of the coating material, and it can vary from 1 to 100 bars.
• the pressure exerted in the compression device makes it possible to compact the sheet of wires and to make the coating layer homogeneous, in particular by giving it a constant thickness, the structure obtained being subsequently frozen by cooling.
• the cooling can take place partly during compression, for example by means of cylinders maintained at a temperature below the point of solidification of the material of lowest melting point, for example between 10 and 130 ° C., preferably at a temperature below 80 ° C, and better still below 60 ° C.
• the compression device can also consist of several calenders, in particular when the thickness is high or if a high degree of flatness and / or a high production rate is desired.
• a non-stick coating such as PTFE
• This material can for example be a film made of silicone paper, for single use or not, or an endless strip of canvas coated with PTFE.
• the compression device is in the form of a band press, for example made of steel, glass cloth or aramid cloth, preferably coated with PTFE.
• the press further comprises a hot zone upstream of the compression device, and a cold zone downstream, the heating or cooling elements being in the form of plates, bars or cylinders (calenders).
• the cooling can take place in the compression device or it can be carried out independently of the compression, for example by natural or forced convection of cold air or by passing over a cooling table.
• the strip obtained at the exit from the cooling zone can be wound on a mandrel of diameter adapted according to the thickness and the rigidity of the strip, or can be cut by a cutting device, for example a cutter or a saw. circular.
• the manufacture of the composite plate can be carried out from a single ply as described above, which corresponds to the simplest embodiment.
• a plate can be formed by associating one or more other plies of threads of different materials and / or structures with the preceding ply in order to form in particular plates greater thickness.
• the plies of threads are preferably formed from fabrics and / or knits and / or continuous threads which are not interlaced.
• the structures come in various forms: wires or assemblies of wires (grids, fabrics), films, sails, sheets, panels, foams, etc.
• They may consist entirely or partly of polyethylene, polypropylene, polyester such as polyethylene terephthalate (PET) and polybutylene terephthalate (PBT), polyamides, polyacrylics, polyurethane, polyester, glass, a metal, and include fillers (talc, calcium carbonate, balsa, wood, cork), adhesives and flame retardants.
• polyester such as polyethylene terephthalate (PET) and polybutylene terephthalate (PBT)
• PET polyethylene terephthalate
• PBT polybutylene terephthalate
• polyamides polyacrylics
• polyurethane polyurethane
• polyester glass
• glass glass
• metal a metal
• fillers talc, calcium carbonate, balsa, wood, cork
• adhesives and flame retardants include fillers (talc, calcium carbonate, balsa, wood, cork), adhesives and flame retardants.
• the structures have a thickness which can vary to a large extent depending on the material used, from 50 micrometers for the sails, films and sheets to several centimeters for the panels. Preferably, the thickness of the structures varies from 0.5 to 2 mm.
• the present invention also relates to a device for implementing the method, this device comprising: a) at least one device for feeding at least one ply of continuous threads, b) at least one powdering device, c) at least a device for heating the sheet coated with powder, d) at least one compression device, and optionally for cooling the sheet.
• the device according to the invention can also comprise at least one cutting device and / or at least one device for collecting the composite plate.
• the plates obtained by the process of the invention are economical because produced continuously. They are formed of a matrix, within which are embedded reinforcing filaments, protected by a coating forming a homogeneous finish layer, of beautiful appearance, which can receive decoration patterns and inscriptions in the form of paint, varnish or stickers. If the finish layer has a nice appearance, in particular a regular, flat and smooth surface without "marking" effect, it is mainly because the reinforcing threads are continuous and that they can be distributed in a manner substantially parallel to the plane. of the web during the compression step.
• the sheets generally have a thickness of 1 to 10 mm, preferably 1 to 6 mm, are easy to cut and have good mechanical properties, in particular good impact resistance (gravel, hail).
• the plates obtained are also rigid but may have sufficient flexibility if necessary to be able to be collected and stored in rolled form. They can also be used for thermoforming and molding of composite parts.
• the composite plate thus obtained can be used as it is or be associated with other flexible or rigid products, in particular for forming sandwich panels having an improved weight / rigidity ratio.
• the rigid product can be in the form of wooden (balsa, agglomerated) or thermoplastic or thermosetting foam sheets, or a honeycomb structure, for example of honeycomb type, based on aluminum, paper or polypropylene.
• the manufacturing of the panel is generally carried out by bonding the composite plate to at least one of the faces of the aforementioned structure by an appropriate means, preferably by gluing.
• the foam-based panels can be obtained from a foam plate cut to the desired dimensions, or be extruded directly onto the composite plate and then subjected to calendering.
• the thickness of the panels can vary from 2 to 100 mm, preferably from 10 to 50 mm.
• the composite plates and the panels formed from these plates are more particularly intended to form walls used in the field of transport (truck bodies, trailers, caravans, camper vans) or of building (cladding, light construction partitions).
• Composite plates have the advantage of being able to be welded without external material supply, and are suitable for being molded, in particular by thermoforming.
• it is easy to repair the coating when it has been damaged simply by depositing the coating powder, possibly dispersed in a liquid or in the form of sealant, and then heating. They can also be easily recycled in the form of granules or small pieces for injection or compression molding.
• FIG. 1 represents a schematic view of a device allowing the implementation of the invention in its simplest embodiment
• Figure 2 shows a schematic view of a device for implementing the invention according to the preferred embodiment.
• FIG. 1 schematically represents a production line for composite plates which comprises upstream at least one winding (1) of a fabric of co-mixed threads.
• the fabric (2) extracted from this winding passes over a return cylinder (3) and a take-up cylinder (4) making it possible to reduce the tension of the sheet, then under a powdering device (5) composed of a cylinder provided with grooves (5) connected to the base of a reservoir (7) filled with the coating powder which distributes the powder over the surface of the fabric.
• the powdered fabric is then heated without contact by infrared radiation panels (8) to a temperature sufficient to allow the melting of the organic matter contained in the threads and of the organic matter of the powder.
• the fabric thus heated passes between pressing rollers (9) which compress the molten organic matter under a force of approximately 5 kN to 50 kN per meter of width, then on a cooling table (10).
• the rigid, cooled composite strip (11) is continuously cut to the desired dimensions by the blades (12) of an automatic shear (not shown) in the form of plates (13) .
• the wires are brought together in wicks which are continuously projected onto the conveyor belt by means of a pneumatic ejection device (not shown) moving transversely relative to said belt, in an alternating movement, to form a matt (or sheet of curly threads).
• FIG. 2 schematically represents an installation making it possible to manufacture a composite plate according to the preferred embodiment of the invention.
• a dusting device (28) Downstream of the conveyor belt (21) and above the fabric-veil association, a dusting device (28) is installed comprising a grooved cylinder (29) connected to a reservoir (30) containing the coating powder.
• a second dusting device (31) can be installed below the combination to allow the application of the powder on the underside. This device is here composed of a nozzle (32) for spraying the powder previously heated by hot air.
• the combination of fabrics and sails coated with powder is introduced into a flat laminating press (33).
• This press essentially comprises two continuous bands (34, 35) driven by a set of rollers (36, 37), a heating zone (38), a zone (39) for cooling by circulation of water, and pressing rollers ( 40) in which the association is compressed and entrained.
• the association is heated by plates (41) to a temperature making it possible to obtain the fusion of the filaments of organic matter and of the powder, and the cylinders (40) helping both to distribute the molten matter uniformly within the association and to compact the tissues (15, 16).
• the second zone (39) cooled by the plates (42) the association is frozen and consolidated.
• a rigid strip is obtained which is wound on a mandrel (43). Each side of the strip has a homogeneous and smooth surface.
• the thickness of the strip is large and does not allow collection in the form of a winding, the latter is cut into panels for example by a circular saw placed on a follower carriage (not shown).
• the fabrics (15, 16) are replaced by two strips (11) collected in the form of windings produced in the installation of FIG. 1.
• EXAMPLE 1 The installation described in FIG. 1 is used to manufacture a composite plate 1.5 m wide and 1.5 mm thick made up of 60% by weight of glass and 40% by weight of polypropylene.
• thermoplastic alloy based on polyolefin sold by Plascoat
• the assembly running at a speed of 1.5 m / minute is heated between the infrared radiation panels (length: 1 m; temperature: 200 ° C) then passes between the rollers (diameter: 300 mm; temperature: 40 ° C ; air gap: 1.5 mm) of the radiator grille.
• the composite plate obtained has a thickness of 1.5 mm and the surface is coated with a homogeneous coating layer, white and shiny, 0.5 mm thick.
• twill 2 binds 2, of 1, 5 m wide, a polyester veil of 70 g / m 2 linked “jet fluid” (Reference NLC 10/701 marketed by PGI) is applied and the thermoplastic alloy powder of Example 1 is applied at the rate of 500 g / m 2 .
• the assembly is introduced into a double belt press comprising a zone heated to 220 ° C, a calender with two cylinders (pressure: 1.5 bar (0.15 MPa)) and a cooling zone at 20 ° C.
• the press operates at a speed of 2 meters per minute.
• a 1.5 mm thick plate is obtained, comprising a homogeneous and shiny coating layer, of white color.
• the assembly traveling at a speed of 1.5 m / minute is heated between the infrared radiation panels (temperature: 220 ° C.) and then enters the grille.
• the composite plate obtained has a thickness of 1.5 mm. It is cut and heated at 220 ° C for 1 minute in an infrared oven, then it is transferred to a press consisting of a rectangular mold and a counter mold regulated at 60 ° C and subjected to a pressure of 40 bars. (4 MPa) for 1 minute.
• FIG. 2 An installation as described in FIG. 2 is used to continuously form sandwich panels 1.5 m wide, 2.4 m long, 22.5 mm thick, made of polyurethane foam covered with plates. composites consisting of 60% by weight of glass and 40% by weight of polypropylene.
• Polyurethane foam panels (length: 1.55 m, width: 1.2 m, thickness: 20 mm, density: 100 kg / m 3 ; reference SPF 100 sold by SAITEC) are juxtaposed on the conveyor. During movement, the panels are coated on their upper and lower faces with a 1485 tex fabric, 4-ply twill 4, consisting of rovings of yarns mixed with 60% by weight of glass and 40% by weight of polypropylene. , then a polyester veil (NLC 10/701 marketed by PGI) at 70 g / m 2 , linked with a fluid jet. Powdering devices deliver 500 g / m 2 of thermoplastic powder
• the temperature of the powder sprayed on the underside is approximately 180 ° C.
• the first zone is 1 m long and the temperature is about 210 ° C
• the second zone 4 m long is kept at about 20 ° C
• the calender is composed of two rollers of 400 mm in diameter each pressing with a force of 2 kN on the whole.
• the air gap of the grille is 22 mm.
• the composite panel comes out continuously with a speed of 0.7 m / min then it is cut using a circular saw into panels 1, 5 m wide and 2.4 m long.
• the composite strips coating each side of the panels have a void rate of less than 3% and a homogeneous coating layer, white in color.
• Example 5 The procedure of Example 4 is modified, in that the panels have a width of 2.9 m and a thickness of 80 mm, and that a double-band steel press is used comprising a zone heated 3 m long and a cold zone of the same length exerting a pressure of 2 bar
• FIG. 2 The installation described in FIG. 2 is used to manufacture panels with honeycomb structure in polypropylene 2.9 m wide, 12 m long, 52.5 mm thick coated with composite plates made up of 60% by weight of glass and 40% by weight of black polypropylene colored in the mass.
• the core structures are made of honeycomb polypropylene honeycomb panels (length: 2.95 m, width: 1.2 m, thickness: 50 mm, density: 80 kg / m 3 ) deposited on the conveyor belt. joined together.
• the temperature of the first hot zone of the belt press is approximately 210 ° C, that of the second zone is approximately 20 ° C and the calender, whose air gap is equal to 52 mm, exerts a pressure of 2 bars (0.2 MPa) on the whole.
• the composite panel comes out continuously with a speed of 2 m / min then it is cut into rectangles.
• EXAMPLE 7 To continuously form a composite plate 2.9 m wide and 16 mm thick consisting of expanded polypropylene foam reinforced with glass strands coated with composite plates consisting of 60% by weight of glass and 40 % by weight of polypropylene, an installation as described in FIG. 2 is used comprising a foam extrusion and calendering device located upstream of the conveyor.
• the core foam is formed in a flat die (not shown) by extrusion from a polypropylene composition comprising 10% by weight of cut glass fibers of length less than 1 mm, and deposited on the conveyor.
• the foam has a thickness of 14mm at the outlet of the die, a width of 2.95 m and a density equal to 300 kg / m 3 .
• the upper and lower faces of the foam are coated with a fabric of 1485 g / m 2 of rovings mixed with 60% by weight of glass and 40% by weight of polypropylene twill 4 to 4, then to a polyester veil (NLC 10 sold by PGI) of 70 g / m 2 , bonded with fluid jet.
• the powdering devices deliver 600 g / m 2 of thermoplastic powder
• the press is a steel belt press comprising a first zone 3 m long at about 220 ° C, a second zone of the same length at about
• the press air gap is set to 16 mm.
• the composite plate comes out continuously at a speed of 2 m / min then it is cut into panels.
• the coating of the plate thus obtained is of excellent quality: it has in particular a beautiful shiny appearance. This is explained by the fact that the foam continues to expand under the effect of heat in the first zone of the strip and that the high pressure of the press makes it possible to have good consolidation of the coating layer.
• Example 2 The procedure is carried out under the conditions of Example 2 modified in that fabrics of 745 g / m 2 of glass strands (60% by weight) are used which are impregnated with a thermosetting epoxy resin brought to stage B of the polymerization. (40% by weight).
• the double-band press is heated to 180 ° C and operates at 1 m / min.
• a 1.5 mm thick plate is obtained, comprising a homogeneous and shiny coating layer, of white color.
• Example 1 The procedure is carried out under the conditions of Example 1 modified in that the coating powder is deposited on the sheet of wires at the rate of 390 g / m 2 .
• the coating of the composite plate thus formed is not homogeneous and lets see the weft of the fabric by transparency in several places.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Chemical & Material Sciences (AREA)
• Composite Materials (AREA)
• Laminated Bodies (AREA)
• Reinforced Plastic Materials (AREA)

Applications Claiming Priority (3)

Publications (1)

Family

ID=32338922

Family Applications (1)

Country Status (9)

Families Citing this family (30)

Family Cites Families (11)

• 2002
  • 2002-12-13 FR FR0216043A patent/FR2848492B1/fr not_active Expired - Fee Related
• 2003
  • 2003-12-10 AU AU2003296797A patent/AU2003296797A1/en not_active Abandoned
  • 2003-12-10 US US10/538,357 patent/US7674495B2/en not_active Expired - Fee Related
  • 2003-12-10 WO PCT/FR2003/003648 patent/WO2004062893A1/fr active Application Filing
  • 2003-12-10 EP EP03815104A patent/EP1575759A1/fr not_active Withdrawn
  • 2003-12-10 JP JP2004566115A patent/JP2006509664A/ja active Pending
  • 2003-12-10 CA CA 2509938 patent/CA2509938A1/fr not_active Abandoned
  • 2003-12-10 CN CNB2003801097396A patent/CN100537199C/zh not_active Expired - Fee Related
  • 2003-12-10 KR KR1020057010842A patent/KR20050091002A/ko not_active Application Discontinuation

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events