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
  • B29C45/00—Injection moulding, i.e. forcing the required volume of moulding material through a nozzle into a closed mould; Apparatus therefor
  • B29C45/16—Making multilayered or multicoloured articles
• • 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
  • B29C45/00—Injection moulding, i.e. forcing the required volume of moulding material through a nozzle into a closed mould; Apparatus therefor
  • B29C45/0001—Injection moulding, i.e. forcing the required volume of moulding material through a nozzle into a closed mould; Apparatus therefor characterised by the choice of material
• • 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
  • B29C45/00—Injection moulding, i.e. forcing the required volume of moulding material through a nozzle into a closed mould; Apparatus therefor
  • B29C45/16—Making multilayered or multicoloured articles
  • B29C45/1657—Making multilayered or multicoloured articles using means for adhering or bonding the layers or parts to each other
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60R—VEHICLES, VEHICLE FITTINGS, OR VEHICLE PARTS, NOT OTHERWISE PROVIDED FOR
  • B60R13/00—Elements for body-finishing, identifying, or decorating; Arrangements or adaptations for advertising purposes
  • B60R13/02—Internal Trim mouldings ; Internal Ledges; Wall liners for passenger compartments; Roof liners
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F21—LIGHTING
  • F21S—NON-PORTABLE LIGHTING DEVICES; SYSTEMS THEREOF; VEHICLE LIGHTING DEVICES SPECIALLY ADAPTED FOR VEHICLE EXTERIORS
  • F21S41/00—Illuminating devices specially adapted for vehicle exteriors, e.g. headlamps
  • F21S41/20—Illuminating devices specially adapted for vehicle exteriors, e.g. headlamps characterised by refractors, transparent cover plates, light guides or filters
  • F21S41/28—Cover glass
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F21—LIGHTING
  • F21S—NON-PORTABLE LIGHTING DEVICES; SYSTEMS THEREOF; VEHICLE LIGHTING DEVICES SPECIALLY ADAPTED FOR VEHICLE EXTERIORS
  • F21S41/00—Illuminating devices specially adapted for vehicle exteriors, e.g. headlamps
  • F21S41/20—Illuminating devices specially adapted for vehicle exteriors, e.g. headlamps characterised by refractors, transparent cover plates, light guides or filters
  • F21S41/2805—Cover glass
• • 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
  • B29C45/00—Injection moulding, i.e. forcing the required volume of moulding material through a nozzle into a closed mould; Apparatus therefor
  • B29C45/16—Making multilayered or multicoloured articles
  • B29C45/1657—Making multilayered or multicoloured articles using means for adhering or bonding the layers or parts to each other
  • B29C2045/1664—Chemical bonds
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
  • B29K2033/00—Use of polymers of unsaturated acids or derivatives thereof as moulding material
  • B29K2033/04—Polymers of esters
  • B29K2033/12—Polymers of methacrylic acid esters, e.g. PMMA, i.e. polymethylmethacrylate
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
  • B29K2069/00—Use of PC, i.e. polycarbonates or derivatives thereof, as moulding material
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
  • B29K2075/00—Use of PU, i.e. polyureas or polyurethanes or derivatives thereof, as moulding material
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
  • B29K2075/00—Use of PU, i.e. polyureas or polyurethanes or derivatives thereof, as moulding material
  • B29K2075/02—Polyureas
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
  • B29K2995/00—Properties of moulding materials, reinforcements, fillers, preformed parts or moulds
  • B29K2995/0018—Properties of moulding materials, reinforcements, fillers, preformed parts or moulds having particular optical properties, e.g. fluorescent or phosphorescent
  • B29K2995/0026—Transparent
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
  • B29K2995/00—Properties of moulding materials, reinforcements, fillers, preformed parts or moulds
  • B29K2995/0037—Other properties
  • B29K2995/0094—Geometrical properties
  • B29K2995/0097—Thickness
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29L—INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES
  • B29L2011/00—Optical elements, e.g. lenses, prisms
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60R—VEHICLES, VEHICLE FITTINGS, OR VEHICLE PARTS, NOT OTHERWISE PROVIDED FOR
  • B60R13/00—Elements for body-finishing, identifying, or decorating; Arrangements or adaptations for advertising purposes
  • B60R13/02—Internal Trim mouldings ; Internal Ledges; Wall liners for passenger compartments; Roof liners
  • B60R2013/0287—Internal Trim mouldings ; Internal Ledges; Wall liners for passenger compartments; Roof liners integrating other functions or accessories

Definitions

• the invention relates to the field of injected plastic parts, in particular luminous devices for motor vehicles.
• Luminous devices for motor vehicles conventionally comprise a casing with an opening forming a connection interface, and a lens fixed to the casing via the connection interface and closing the opening.
• the case is conventionally made of injected opaque plastic material.
• the crystal usually made of glass in the past, has for several years been commonly made of injected transparent plastic material, such as in particular polymethyl methacrylate PMMA, polycarbonate PC.
• injected transparent plastic material such as in particular polymethyl methacrylate PMMA, polycarbonate PC.
• These thermoplastic materials commonly sold in the form of granules, are heated to a temperature exceeding the glass transition temperature, to then be injected. However, they have a high viscosity, requiring high injection pressures. A high injection pressure requires a suitable injection press, which can significantly increase the manufacturing cost.
• the aim of the invention is to overcome at least one of the drawbacks of the aforementioned state of the art. More particularly, the aim of the invention is to produce plastic parts of luminous devices, having increased optical and mechanical properties and this in an economical manner.
• the subject of the invention is a part of a luminous device for a motor vehicle, comprising a substrate made of a first thermoplastic material; a coating placed on the substrate, made of a second plastic material; remarkable in that the second plastic material consists of polyurethane PUR, polyurea PUA or a combination of PUR and PUA.
• the part of the luminous device may also have one or more of the following characteristics, taken alone or in combination.
• the first and second materials have between them, at an interface between said materials, polar bonds.
• These polar connections are the result of reactive injection molding of the two materials, namely two separate injections but in the same manufacturing process where the second material is injected after the first material, that is to say when the latter ci is not yet cooled to room temperature, the second crosslinking material by chemical reaction of a polyol with an isocyanate.
• the first thermoplastic material comprises polymethyl methacrylate PMMA, polycarbonate PC, a combination of PMMA and PC.
• the substrate forms a wall with an average thickness which is greater than an average thickness of the coating.
• the coating has an average thickness of between 0.1 and 10 mm, preferably between 1 and 5 mm.
• the substrate and the coating are transparent, each having a transmittance for visible light of at least 92%.
• the second material consists of PUA.
• the second material consists of PUR.
• said part is a lens for closing the luminous device.
• the coating forms an outer surface of said part, capable of self-repairing by applying a heat source to said coating.
• the structure of the second material comprises an alignment and a superposition of short chains, of the order of one hundred to a few thousand carbon atoms, typically between one hundred and eight thousand carbon atoms.
• the second material exhibits the behavior of an oligomer.
• the coating forms an inner surface of said part, provided with optical microstructures.
• microstructures is meant structures or geometric shapes having a main dimension less than or equal to 10 -3 mm.
• the microstructures may have nanometric dimensions.
• the microstructures can be optical, such as for example diffractive.
• the microstructures can also confer a hydrophobic function.
• the invention also relates to a luminous device for a motor vehicle comprising a part in accordance with the present disclosure.
• the subject of the invention is a method for manufacturing a part of a luminous device for a motor vehicle, comprising the following successive steps: injection of a first thermoplastic material into a mold with a first geometry, so as to form a substrate ; injection of a second plastic material into the mold with a second geometry, while the first material has not completely cooled to room temperature, so as to form a coating on the substrate; remarkable in that the second plastic material consists of polyurethane PUR, polyurea PUA or a combination of PU and PUA, in particular a combination of PUR and PUA.
• the measures of the invention are advantageous in that they make it possible to produce parts of a luminous device, in particular optical parts, of complex shape while exhibiting particular mechanical and/or optical qualities, such as resistance to scratches and/or microstructures, respectively.
• the cost of production is also limited in that the coating is thin in relation to the substrate which is itself made of a less expensive thermoplastic material.
• FIG 1 is a sectional view of a light device glass, according to a first embodiment of the invention.
• FIG 2 is a sectional view of a light device glass, according to a second embodiment of the invention.
• FIG 3 is a schematic sectional view of a plastic injection press with a rotating mold, illustrating the injection of a first material, according to the invention
• FIG 4 is a schematic sectional view of a plastic injection press with a rotating mold, corresponding to Figure 3, however illustrating the injection of a second material, according to the invention.
• Figure 1 is a schematic representation of a light device lens, according to a first embodiment of the invention.
• the glass 2 comprises a transparent wall 4 and a mounting foot 6 to a housing (not shown) of the light device.
• the wall 4 in this case forms a left surface.
• the fixing foot 6 is formed integrally with the wall 4, at one edge of the latter.
• the wall 4 comprises a substrate 4.1 made of a first transparent plastic material of the thermoplastic type, such as for example polymethyl methacrylate PMMA, polycarbonate PC, or even a combination of PMMA and PC. The use of this type of material for this type of application is in itself well known.
• the substrate 4.1 is then made by injecting the plastic into a mould.
• the wall 4 further comprises a coating 4.2 forming in this case an outer face of the glass 2.
• This coating has the function of forming a protective layer of the glass 2, that is to say protecting it from attacks exterior, including scratches.
• This coating 4.2 has self-repairing properties, that is to say an ability to reduce or eliminate damage such as scratches by applying heat in order to increase its temperature. This property is known per se and also commonly referred to by the term self-healing.
• the coating 4.2 is made of a second material PUA polyurea plastic.
• PUA is the product of a union between an isocyanate and various polyamines, more specifically a polyaddition of an aliphatic or aromatic isocyanate or an isocyanate prepolymer to a polyfunctional amine or a mixture of amines.
• PANADUR® under the product name PANADUR CLEAR FAST.
• This product is two-component, namely a base component and a hardener. It is transparent and is commonly used as a coating of the “gelcoat” type for composite material comprising a matrix such as a resin, and carbon or glass fibers.
• the inventors of the present invention have discovered that a plastic material based on PUA can be injected with a substrate such as the substrate detailed above in order to form a coating having protective properties of the substrate, replacing potentially more expensive varnishes.
• the protective properties include a high hardness which can be adjusted by the ratio between the components of the PUA-based plastic material, and also by a self-healing or self-repairing capacity. This property is due to the structure of the plastic material in question, namely an alignment and superposition of short chains, typically of the order of a hundred carbon atoms. A scratch, such as a microgroove formed by the movement of a pointed object on the coating, will separate these short chains on several superimposed layers. An increase in the temperature of the coating, by application of an external heat source (such as a hair dryer), typically to reach 60-90°C, will allow these short chains to reorganize by realigning in a superimposed manner .
• an external heat source such as a hair dryer
• PUA has a low dynamic viscosity, typically between 1.3 and 2 Pa.s at 20°C, close to that of water, favoring implementation by injection.
• co-injection it is meant that the first and second plastic materials are injected in the same manufacturing process, preferably in the same mould, however at different times, in order to allow the first plastic material injected first to solidify somewhat. before injecting the second plastic material.
• the use of the same mold does not exclude that the substrate obtained by the first injection, namely of the first plastic material, is transferred into another cavity whose geometry is different in order to perform the second injection therein, in the occurrence of the second plastic material.
• the PUR is also capable of being used, as a replacement for the PUA, within the framework of the first embodiment.
• Figure 2 is a schematic representation of a light device glass, according to a second embodiment of the invention.
• the reference numbers of the first embodiment are used to designate the identical or corresponding elements of the second embodiment, these numbers being however increased by 100. Reference is also made to the description of these elements within the framework of the first embodiment. of achievement.
• the crystal 102 differs from that of the first embodiment essentially in that the coating 104.2 of the wall 104 forms an inner face of said wall and forms a microstructure 104.3.
• the microstructure 104.3 advantageously has optical properties such as in particular diffractive properties.
• optical microstructures on an inner face of luminous device glass is in itself known to those skilled in the art.
• this is made by a second plastic material forming a coating 104.2 of the substrate 104.1 made of a first thermoplastic material such as polymethyl methacrylate PMMA, polycarbonate PC, or a combination of PMMA and PC.
• the second plastic material may be based on PUR polyurethane injected onto the first plastic material.
• Such a plastic material is commercially available in particular from the company RÜHL Puromer GmbH, under the names puroclear® 3351 IT and 3098/4IT with implementation with puronate® 960/1. These materials are transparent with a transmittance of more than 92% and a low viscosity, of the order of 1 to 2.5 Pa.s at 25°c, i.e. very close to the viscosity of water. This plastic material is therefore particularly advantageous for implementation by injection in order to form the microstructures 104.3.
• thermoplastic plastic material such as PMMA or PC presents difficulty when producing long parts in that high injection pressures are required.
• the high viscosity of the molten plastic material injected into a mold generates flow resistance forces which increase with the injection length from the point of entry of said material into the mould. This means that the injection pressure at the mold entrance, then potentially high, gradually decreases along this distance to the farthest end of the material being injected.
• the PUA is also able to be used, replacing the PUR, within the framework of the second embodiment.
• first coating on a first face of the substrate, forming the outer face of the part, and a second coating on an opposite face of the same substrate, then forming the inner face of the part.
• first and second coatings can then be according to one of the coatings of FIGS. 1 and 2.
• the second plastic material is advantageously PUR, PUA, or a combination of PUR and PUA, essentially due to their low dynamic viscosity allowing them to be injected without difficulty in thin layers.
• the substrate in the first plastic material then forms the major part of the part, in this case the ice. It can form at least 70%, preferably at least 80%, by mass of the part in question.
• the first inexpensive plastic material thus makes it possible to limit the cost of production.
• PUR and PUA also have the advantage of being able to be transparent, and thus allow the production of optical parts such as the crystals of light devices described above or even lenses.
• the coating may have an average thickness greater than or equal to 0.5 mm, preferably 1 mm, and/or less than 10 mm, preferably 5 mm.
• the substrate advantageously has an average thickness greater than the average thickness of the coating, more advantageously greater than 3 times the average thickness of the coating.
• Figures 3 and 4 illustrate an embodiment of the injection of the first and second plastic materials, by means of a rotary mold.
• Figure 3 is a schematic sectional view of an injection molding machine with a rotating mold.
• the injection press 8 comprises a first injection screw 8.1 for the first plastic material and a second injection screw 8.2 for the second plastic material.
• the rotary mold 10 comprises a fixed part 10.1 and a rotatable part 10.2.
• the fixed part 10.1 is fixed to the injection pressure 8 and comprises a first face 10.1.1 and a second face 10.1.2 different from the first face 10.1.1.
• the mobile part 10.2 comprises, similarly, a first face 10.2.1 and a second face 10.2.2. Unlike the fixed part 10.1 of the mold 10, the first and second faces 10.2.1 and 10.2.2 are identical.
• the first side is fixed part 10.1 and a rotatable part 10.2.
• the fixed part 10.1 is fixed to the injection pressure 8 and comprises a first face 10.1.1 and a second face 10.1.2 different from the first face 10.1.1.
• the mobile part 10.2 comprises, similarly, a first face 10.2.1 and a second face 10.2.2. Unlike the fixed part 10.1 of the
• Figure 4 illustrates the injection press and the mold of figure 3 at a stage where the second plastic material is injected by the second injection screw 8.2.
• the components of the second plastic material can be mixed in the injection screw before injection into the mold 10.
• the movable part 10.2 of the mold 10 is moved closer to the fixed part 10.1 so that the second face 10.2. 2 of the movable part 10.2, carrying the substrate 4.1, engages with the second part
• the second plastic material can then be injected therein so as to form the coating 4.2, the latter being deliberately represented with an exaggerated thickness, for the purposes of clarity of presentation.
• the first plastic material forming the substrate 4.1 is still hot when the second plastic material is injected, so that the two plastic materials have chemical cohesion at their interface. This chemical cohesion is in the absence of adhesive, it is achieved by covalent or polar bonds between the first and second plastic materials.
• the components of the second plastic material can be mixed in a mixer attached to the injection press. The second plastic material is then transferred into the mold via a nozzle.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Manufacturing & Machinery (AREA)
• General Engineering & Computer Science (AREA)
• Injection Moulding Of Plastics Or The Like (AREA)
• Casting Or Compression Moulding Of Plastics Or The Like (AREA)
• Arrangements Of Lighting Devices For Vehicle Interiors, Mounting And Supporting Thereof, Circuits Therefore (AREA)
• Non-Portable Lighting Devices Or Systems Thereof (AREA)
• Moulds For Moulding Plastics Or The Like (AREA)

Applications Claiming Priority (2)

Publications (1)

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ID=76034669

Family Applications (1)

Country Status (7)

Families Citing this family (3)

Family Cites Families (20)

• 2020
  • 2020-12-18 FR FR2013712A patent/FR3117917B1/fr active Active
• 2021
  • 2021-12-17 KR KR1020237019859A patent/KR20230104961A/ko active Pending
  • 2021-12-17 JP JP2023537040A patent/JP2023553724A/ja active Pending
  • 2021-12-17 EP EP21843607.9A patent/EP4263170A1/de active Pending
  • 2021-12-17 WO PCT/EP2021/086665 patent/WO2022129620A1/fr not_active Ceased
  • 2021-12-17 CN CN202180083633.1A patent/CN116583396A/zh active Pending
  • 2021-12-17 US US18/255,974 patent/US20240035637A1/en active Pending

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