Coated articles

Abstract

The present invention relates to an article comprising a carrier provided at least partially together with a coating layer, wherein i) the carrier comprises or consists of a thermoplastic composition, the thermoplastic composition comprising polycarbonate, ii) the coating layer is applied directly to the carrier and comprises or consists of a polyurethane obtained by reacting at least one diisocyanate or triisocyanate with at least one polyol, iii) the polycarbonate comprises at least 50% by weight of a first polycarbonate having a terminal hydroxyl content of at least 500 ppm based on the weight of the polycarbonate, and the thermoplastic composition comprises polyethylene terephthalate, polybutylene terephthalate, acrylonitrile-butadiene-styrene copolymer, styrene-acrylonitrile copolymer, optionally functionalized polypropylene, optionally functionalized polyethylene, optionally functionalized polyolefin elastomer, (meth)acrylic acid-polybutadiene core-shell copolymer, and polymers selected from the group consisting of at least two mixtures of the above.

Description

Technical Field

[0001] The present invention relates to a coated article. More specifically, the present invention relates to an article comprising a carrier and a polyurethane coating layer applied directly to at least a part of the carrier, wherein the carrier comprises or consists of a thermoplastic composition containing polycarbonate.

Background Art

[0002] Polycarbonate or polycarbonate-based compositions are well known for use in both exterior and interior automotive applications. To protect such articles from scratching, weathering, or chemicals, protective coatings are typically applied. For example, head lenses made of polycarbonate are generally provided with a hard coat having a thickness of several micrometers. Typically, these are acrylic or siloxane-based coatings.

[0003] In the automotive industry, new requirements and standards related to the impact properties of front panels of automobiles, especially electric vehicle vehicles, have been introduced. These requirements specify that in the event of an accident, i.e., a collision with a human or animal, front parts such as front panels should minimize damage to the human or animal. This can be achieved if the formation of sharp and / or brittle parts resulting from the collision is respectively avoided. Likewise, the front parts must not be broken or damaged by the collision. Although these requirements are addressed to some extent by the actual design of the panel or part, these requirements are also at least partially influenced by the properties of the coated part or panel. Therefore, it is preferred that the part or panel exhibits at most ductile impact fracture rather than brittle impact fracture.

[0004] Apart from the mechanical structure, there are also aesthetic requirements, such as the coating adhering sufficiently to the carrier and not peeling over time. This requirement is particularly important for automotive interior applications, such as interior trim bezels integrated with consoles, equipment panels, or door panels.

[0005] Therefore, an object of the present invention is to provide a coated article having sufficient or improved coating adhesion, and / or having any negative effects of the coating on the mechanical properties of the carrier, i.e., the uncoated article, minimized or further improved.

[0006] Prior art has disclosed the interaction between polyurethane and polycarbonate.

[0007] US2019 / 0232621 discloses a multilayer article comprising: i) a high-density substrate layer comprising a polymer composition, wherein the polymer composition is a blend comprising a polycarbonate polymer, a toughening component comprising a rubber-modified monovinylidene aromatic thermoplastic containing an impact modifier, and a filler comprising wollastonite; and ii) a polyurethane cover layer directly bonded to the high-density substrate layer, wherein the amount of polyester in the polymer composition is about 0 or less than about 5% by weight. According to this reference, it has been found that substrates formed of ABS (and in particular, mass ABS) combined with the specified maximum amount of polycarbonate together with the wollastonite filler result in improved adhesive performance (initial adhesion and adhesion after climate aging) when overmolded or painted with a polyurethane layer.

[0008] US2019 / 0153218 is a) A) 55 to 75 parts by weight of at least one polymer selected from the group consisting of aromatic polycarbonates and aromatic polyester carbonates; B) At least one mixture comprising 25 to 45 parts by weight of at least one polybutadiene-based graft polymer prepared by emulsion, suspension, or solution polymerization, and at least one polybutadiene-free vinyl(co)polymer; and C) Contains at least one polymer additive in an amount of 0.1 to 20.0 parts by weight (in each case, based on the total of components A and B), and the polybutadiene content based on the total of parts by weight of components A and B is 10% to 20% by weight. The present invention discloses a composite component comprising a carrier composed of a thermoplastic composition in which the total content of butadiene-free vinyl(co)polymer derived from component B, based on the sum of parts by weight of components A and B, is 12% to 23% by weight, and the sum of parts by weight of components A and B in the polycarbonate composition is normalized to 100, and b) at least one polyurethane layer selected from the group consisting of coating materials, foams, and dense skins, comprising b) at least one polyisocyanate component; at least one polyfunctional H-active compound; and optionally, at least one polyurethane additive and / or processing aid having a molar ratio of NCO-:H-active groups of 1:1 to 1.1:1.

[0009] US2002 / 01670177 is a polycarbonate composition comprising (A) an aromatic polycarbonate and / or polyester carbonate, (B) a graft polymer, and (C) a copolymer of styrene and at least one monomer containing at least one carboxyl group, The above copolymer is disclosed for a polycarbonate composition having a weight-average molecular weight M of 10,500 g / mol or more. According to this reference, it was discovered that by adding copolymer (C), a significant improvement in foam adhesion, particularly foam adhesion to polyurethane foam, can be achieved.

[0010] US5,688,837 discloses a method for bonding a polyurethane foam to polycarbonate, comprising: a) providing a nucleophilic radical to the surface of the polycarbonate; b) producing a polyurethane mix comprising at least one polyol and at least one diisocyanate, wherein the polyurethane mix exhibits an isocyanate index greater than 82; and c) forming the polyurethane mix on the surface of the polycarbonate. According to this reference, the polycarbonate must have at least one nucleophilic radical on its surface. The nucleophilic radical can be introduced by processing during the production of the polycarbonate. The nucleophilic radical can be formed on the polycarbonate during polymerization. For example, bisphenol A polycarbonate produced by a melt transesterification process contains a hydroxyl nucleophilic radical.

[0011] US2011 / 0027575 discloses a method for producing a composite material, comprising (i) producing a foamed polycarbonate molded composition by injection molding using chemical and / or physical foaming techniques, and (ii) applying a polyurethane reaction system to the top of the polycarbonate molded composition and curing it.

[0012] US2006 / 0151911 discloses an in-mold coating process comprising (i) obtaining a mold having at least two cavities, (ii) molding a thermoplastic substrate in the first cavity, (iii) introducing the substrate into the second cavity, and (iv) coating the substrate with lacquer, the coating being performed under high pressure, and the coating being cured. The method disclosed in this reference is suitable for lacquer layer thicknesses in the range of 0.01 to 3 mm.

[0013] W02024 / 017706 describes a method for preparing a composite component with improved interlaminated bonding, the component comprising a carrier containing polycarbonate and at least one polyurethane layer in direct contact with the carrier. The present invention also relates to a composite component with improved interlaminated bonding, and to the use of polycarbonate having a defined OH content as a carrier material in the preparation of a composite component with improved interlaminated bonding.

[0014] EP4309865 describes a method for producing a composite component with improved interlaminated bonding, the component comprising a carrier containing polycarbonate and at least one polyurethane layer in direct contact with the carrier. The present invention also relates to a composite component with improved interlaminated bonding, and to the use of a composition containing polycarbonate and a special hydroxyl group component as a carrier material in the production of a composite component with improved interlaminated bonding. [Overview of the Initiative] [Problems that the invention aims to solve]

[0015] While the prior art generally discloses material-based articles that include polycarbonate and can be combined with polyurethane coatings or foam layers, the prior art does not mention the use of such materials in certain automotive applications, particularly in front panel applications for electric vehicles. [Means for solving the problem]

[0016] From that perspective, the present invention relates to an article comprising a carrier provided at least partially together with a coating layer, - The carrier comprises or consists of a thermoplastic composition, and the thermoplastic composition comprises polycarbonate. - The above coating layer is applied directly to the above carrier and contains, or is made of, a polyurethane obtained by reacting at least one diisocyanate or triisocyanate with at least one polyol. - The above polycarbonate comprises at least 50% by weight of a first polycarbonate, which, when measured according to the method described herein based on the weight of the above polycarbonate, has a terminal hydroxyl content of at least 500 ppm, preferably at least 700 ppm.

[0017] More specifically, the present invention relates to an article comprising a carrier provided at least partially together with a coating layer, - The carrier comprises or consists of a thermoplastic composition, and the thermoplastic composition comprises polycarbonate. - The above coating layer is applied directly to the above carrier and contains, or is made of, a polyurethane obtained by reacting at least one diisocyanate or triisocyanate with at least one polyol. -The polycarbonate comprises at least 50% by weight of a first polycarbonate having a terminal hydroxyl content of at least 500 ppm, preferably at least 700 ppm, as measured according to the method described herein, based on the weight of the polycarbonate, and the thermoplastic composition comprises polymers selected from the group consisting of polyethylene terephthalate, polybutylene terephthalate, acrylonitrile-butadiene-styrene copolymer, styrene-acrylonitrile copolymer, optionally functionalized polypropylene, optionally functionalized polyethylene, optionally functionalized polyolefin elastomer, (meth)acrylic acid-polybutadiene core-shell copolymer, and mixtures of at least two of the above.

[0018] While not wishing to be bound by this, the inventors hold the view that improved coatings, i.e., improved coating adhesion, are obtained because the isocyanate groups of the two-component polyurethane coating react with the naturally occurring phenol-OH groups on the molten polycarbonate chains. From these bonded isocyanate groups, polyurethane chains can grow and form at least partially crosslinked coating layers that are chemically bonded to carriers.

[0019] A carrier referring to the context of the present invention comprises or consists of a thermoplastic composition containing polycarbonate, wherein the polycarbonate comprises at least 50% by weight of a first polycarbonate having a terminal hydroxyl content of at least 500 ppm, preferably at least 700 ppm, based on the weight of the polycarbonate.

[0020] Carriers are typically obtained by molding a thermoplastic composition, preferably by injection molding, such as by injection molding, extrusion molding, or compression molding. The carrier is preferably composed of a thermoplastic composition. However, the carrier may also include further components, such as non-thermoplastic compositions, that come into contact with a portion of the carrier produced from the thermoplastic composition. For example, a carrier may be molded from two components, where a first surface part of the carrier is made of a thermoplastic composition and the other surface part is not made of a thermoplastic composition. In the context of such an embodiment, the coating layer is applied to the surface of the carrier, at least partially, which is made of a thermoplastic composition. However, typically, and in preferred embodiments, the carrier is made of a thermoplastic composition, particularly in the form of a molded part, such as by injection molding. The coating layer may cover the entire surface of the carrier or only a portion of it. To avoid misunderstanding, in the context of the present invention, it should be understood that the coating layer is applied directly to the thermoplastic composition, and there is no other layer between the coating layer and the thermoplastic composition. This can be achieved by applying the coating to the carrier after the carrier has been manufactured in a molding apparatus.

[0021] The thermoplastic composition preferably comprises at least 75 wt.%, more preferably at least 85 wt.%, more preferably at least 95 wt.%, even more preferably at least 98 wt.% of polycarbonate, based on the weight of the thermoplastic composition.

[0022] According to the present invention, the thermoplastic composition may further comprise a polymer selected from the group consisting of polyethylene terephthalate, polybutylene terephthalate, acrylonitrile-butadiene-styrene copolymer, styrene-acrylonitrile copolymer, optionally functionalized polypropylene, optionally functionalized polyethylene, optionally functionalized polyolefin elastomer, (meth)acrylic acid-polybutadiene core-shell copolymer, and mixtures of at least two of the foregoing.

[0023] The thermoplastic composition may comprise known additives such as colorants, fillers, reinforcing fillers or fibers, antioxidants, UV stabilizers, release agents, flame retardants and the like. However, it is preferred that the thermoplastic composition is free of antistatic agents, as antistatic agents may migrate to the surface of the molded article and, depending on the type of antistatic agent, may negatively affect the adhesion of polyurethane.

[0024] The polycarbonate may be a single type of polycarbonate or a mixture of at least two different polycarbonates. Further, the polycarbonate may be a single grade, or a mixture of polycarbonates of the same type but of different grades, having different molecular weights, and / or different production methods, and / or different amounts of terminal hydroxyl content, and / or different end-capping rates, and / or different amounts of fleece content.

[0025] The first polycarbonate preferably consists of one or more bisphenol A polycarbonate homopolymers. It is further preferred that the polycarbonate consists of one or more bisphenol A polycarbonate homopolymers.

[0026] Commercially available polycarbonates, particularly bisphenol A polycarbonate homopolymers, can be obtained by two different manufacturing methods.

[0027] In the so-called interfacial method, one or more bisphenols, typically bisphenol A, react with a carbonate source such as phosgene in a two-phase liquid system. Such a two-phase system consists of an organic phase and an aqueous phase. The reaction typically occurs at the interface between the two phases, where the growing polymer chains remain dissolved in the organic phase. Interfacial polymerization is typically terminated by adding end-terminating agents, particularly phenolic end-terminating agents such as phenol, tert-butylphenol, and paracumylphenol. As a result, the interfacial polycarbonate typically contains little to no phenolic hydroxyl groups, i.e., terminal hydroxyl groups. Nevertheless, the above method has been disclosed in the prior art to increase the amount of hydroxyl groups in the interfacial polycarbonate. Such methods are disclosed, for example, in US 5,567,802 and 5,886,073, which are incorporated herein by reference.

[0028] In some cases, in a so-called melting process, also known as the melting transesterification or melting polycondensation process, one or more bisphenols, typically bisphenol A, react with diaryl carbonates, such as diphenyl carbonate in particular. This reaction is carried out in a molten phase consisting of raw materials and, optionally, one or more catalysts. No solvent is used, and the reaction medium is a single-phase system. In this method, bisphenol A reacts with diphenyl carbonate, thereby releasing phenol from the reaction medium. Typically, since no end-terminating agents are added in the melting process, the level of phenolic hydroxyl groups in molten polycarbonate is much higher than in interfacial polycarbonate. Apart from having a much higher phenolic hydroxyl group content, molten polycarbonate is further distinguished from interfacial polycarbonate in that it contains branched units as a result of the Fries rearrangement reaction that occurs at the relatively high temperatures in which transesterification takes place. The difference between "molten polycarbonate" and "interfacial polycarbonate" is well known to those skilled in the art.

[0029] The polycarbonate in the thermoplastic composition preferably contains at least 75% by weight, preferably at least 90% by weight, and more preferably at least 95% by weight of a first polycarbonate. It is more preferable that the polycarbonate consists of the first polycarbonate, meaning that there are no further polycarbonates in the polycarbonate other than the first polycarbonate.

[0030] The polycarbonate in the thermoplastic composition preferably has a terminal hydroxyl content of at least 500 ppm, preferably at least 700 ppm, as measured according to the method described herein. To avoid misunderstanding, the term “polycarbonate” may include mixtures of polycarbonates.

[0031] The first polycarbonate and / or the terminal hydroxyl content of the polycarbonate may be up to 2500 ppm, preferably up to 2000 ppm, more preferably up to 1500 ppm, or even more preferably up to 1250 ppm.

[0032] The first polycarbonate is preferably molten polycarbonate. The polycarbonate of the thermoplastic composition is preferably made of molten polycarbonate.

[0033] The polycarbonate in the thermoplastic composition preferably contains, essentially comprises, or comprises a bisphenol A polycarbonate homopolymer (or multiple homopolymers).

[0034] According to ISO 1133 (1.2 kg, 300°C), polycarbonate has a thickness of 5-40 cm. 3 / 10 minutes, preferably 6-32 cm 3 / 10 minutes, for example, 10-26cm 3 It is preferable to have a melt volume rate of 10 minutes. The first polycarbonate, when measured according to ISO 1133 (1.2 kg, 300°C), has a melt volume of 5-40 cm². 3 / 10 minutes, preferably 10-32 cm 3 It is preferable to have a melt volume rate of / 10 minutes.

[0035] The polycarbonate preferably has an end-to-end encapsulation rate (EC%) of up to 85%, preferably 25-85%, more preferably 30-80%, 50-80%, or 65-75%, and the end-to-end encapsulation rate is calculated according to the following formula I.

[0036]

number

[0037] Therefore, end-capping percentage is defined as the percentage of polycarbonate chain ends that are not hydroxyl groups. For example, a polycarbonate with a 75 mol% end-capping percentage means that the polycarbonate has 25 mol% of chain ends that are typically hydroxyl end groups derived from bisphenol A monomers. The other 75 mol% of end groups do not contain OH end groups and may be phenols or may correspond to end-terminating molecule(s).

[0038] In embodiments where the first polycarbonate is molten polycarbonate, the molten polycarbonate preferably has a fleece branching or fleece content of 100 to 1500 ppm, for example, 400 to 1200 ppm.

[0039] coating The coating layer in the article of the present invention is obtained by coating a carrier with a liquid coating comprising at least one polyisocyanate and at least one polyol. The resulting coating is a polyurethane coating. The polyisocyanate is preferably a diisocyanate or triisocyanate, or a mixture of diisocyanate and triisocyanate. A single polyisocyanate or a mixture of different polyisocyanates may be used. Similarly, a single polyol or a mixture of different polyols may be used. The polyol is preferably a diol, i.e., a compound having two hydroxyl functional groups.

[0040] Two-component polyurethane coatings are known to those skilled in the art, and in principle, any available coating system of this kind can be applied in the context of the present invention. This is because the inventors consider the underlying idea of ​​the present invention to be the interaction between terminal hydroxyl groups derived from polycarbonate and isocyanate groups.

[0041] In the context of the present invention, the coating layer is not foamed, i.e., the coating layer substantially does not contain voids; however, it will be recognized that in a typical wet coating process, the (unintentional) formation of small voids or bubbles cannot always be prevented.

[0042] In addition to the isocyanate index, the desired properties of the coating layer can be obtained by selecting appropriate polyisocyanates and polyols. The isocyanate index corresponds to the ratio of free isocyanate groups to isocyanate-reactive groups such as hydroxyl groups derived from polyols, amines, and water, before the reaction occurs. To avoid misunderstanding, the terminal hydroxyl content of the polycarbonate is not taken into account in the calculation of the isocyanate index. An isocyanate index of 1 indicates that the number of isocyanate equivalents is equal to the number of hydroxyl groups, amine groups (if present), and water (if present). Typically, amine groups and water are absent. Water has 2 equivalents per mole, primary amines have 2 equivalents, and secondary amines have 1 equivalent. The isocyanate index is preferably 0.90 to 1.2, and more preferably 0.95 to 1.1. In particular, for polycarbonates with a large number of terminal hydroxyl groups, a somewhat higher isocyanate index may be preferred compared to polycarbonates with a small number of terminal hydroxyl groups.

[0043] The coating layer, after curing, is preferably at least 50 μm, preferably at least 100 μm, more preferably at least 250 μm, and up to 5000 μm, preferably up to 4000 μm, and more preferably up to 2500 μm.

[0044] panel The articles of the present invention are preferably automotive interior articles or automotive exterior articles.

[0045] Interior articles may include, or constitute, the dashboard, equipment panels, console, display, functional surface trim, or door trim.

[0046] Exterior articles may include, or constitute, the front panel, side panels, or rear panels of a vehicle.

[0047] In particular, the article may be included in or constitute a vehicle front panel, such as the front panel of a car, truck, or bus. In such applications, the coating layer is exposed in the direction of driving, i.e., outward. The article is more preferably included in or constitutes a front panel of an electric vehicle, such as an electric car, truck, or bus. To avoid misunderstanding, the present invention relates to the use of the article as part of or as a front panel as described above.

[0048] The present invention further relates to vehicles such as fossil fuel-based cars, trucks, or buses, electric vehicles, trucks, or buses, or electric and fossil fuel-based hybrid cars, trucks, or buses, including articles disclosed herein that conform to the present invention.

[0049] method The present invention further relates to a method for manufacturing an article disclosed herein, the method being: i) The step of forming the carrier by injection molding by injecting a certain amount of thermoplastic composition into a mold, ii) A step of cooling the injection-molded article, iii) A step of directly applying a two-component polyurethane coating containing at least one polyisocyanate and at least one polyol to at least a portion of the injection-molded article, iii) a step of curing the above coating, The above thermoplastic composition comprises polycarbonate, wherein the polycarbonate comprises at least 50% by weight of a first polycarbonate having a terminal hydroxyl content of at least 500 ppm, preferably at least 700 ppm, based on the weight of the polycarbonate.

[0050] The cooled, injection-molded article from step ii) is transferred to a second cavity, and it is preferable that at least step iii) is carried out in the second cavity.

[0051] In step iii), it is even more preferable that, in order to further increase the amount of hydroxyl groups on the surface of the injection-molded part before applying the coating, at least the part that will become the coating surface of the injection-molded article is subjected to corona or flame treatment.

[0052] Typically, the method is carried out in a process known as flood coating or in-mold coating. In such a process, the carrier is manufactured by injection molding in an injection molding apparatus. After the injection of the thermoplastic composition, the formed carrier is cooled until it is fully solidified. Next, while the carrier is still in the mold, the coating is injected to cover at least one side or part of the carrier. This can be carried out in the same mold, or preferably in the second cavity described above. The coating is then cured, typically under pressure, until the carrier can be removed from the mold. After the carrier is removed from the mold, the coating may or may not be fully cured. [Modes for carrying out the invention]

[0053] The present invention will be further clarified based on the following non-limiting examples.

[0054] Measurement method JPEG2026534541000002.jpg243170 Polycarbonate material [Table 1]

[0055] Polycarbonates PC1 to PC5 are all bisphenol A polycarbonate homopolymers.

[0056] Coating adhesion Polycarbonate samples PC1-PC5 were molded into plaques with a thickness of 3 mm, and then a two-component polyurethane coating was applied. The polyurethane coating was Puroclear 3351iT, available from Ruhl. This coating is a two-component polyurethane coating containing polyester polyol and isocyanate, with a weight ratio of polyol to isocyanate of 100:230. The thickness of the cured coating was 0.6 mm.

[0057] Next, using a Dolly with a diameter of 20 mm and an applied tensile stress rate of 0.7 MPa / s, we performed the standard ISO 4624 Method B (No. 3 According to the 2016 edition, the resulting coated articles were passed through a so-called Positest. The adhesive used was LORD406E / 17 acrylic adhesive. The tests were carried out at room temperature of 23±2°C and relative humidity of 50±5%. The adhesion of the coating to the substrate was tested using a Positest known to those skilled in the art.

[0058] After the coating had fully cured (typically about 24 hours later, but before the samples were aged), a Positest was performed on the coated articles. Another Positest was performed on the obtained samples by putting the coated and fully cured articles through an aging cycle in accordance with the BMWPR303.5b climate test. This climate test involved exposing the articles to temperatures within the -30°C to 80°C cycle range under different relative humidity conditions during the cycle. The total duration of the cycle was 240 hours. The BMWPR303.5b climate test is well known to those skilled in the art.

[0059] The test results are shown in Table 2. [Table 2]

[0060] The results shown in Table 2 indicate that polycarbonate articles with relatively high terminal hydroxyl content exhibit improved adhesion to two-component polyurethane coatings based on isocyanate and polyol monomers. A clear effect is observed both before and after aging. The reason for the difference in post-aging Positest results between PC4 and PC5 is not fully understood by the inventors. A possible explanation is that differences in fleece content in these polycarbonates may be involved.

[0061] Further examples provided several polycarbonate plaques, including a two-component polyurethane coating based on isocyanate monomer and polyol monomer. The coating was Puroclear 3098-4IT, commercially available from Ruhl, and was applied to a cured coating layer thickness of 0.6 mm. After curing, the peel strength of the coating was measured according to ASTM D3167. The results are shown in Table 3 below. [Table 3]

[0062] The inventors have discovered that when using interfacial polycarbonates that lack terminal hydroxyl groups or have negligible terminal hydroxyl groups, the peel strength cannot be measured.

[0063] The data in this table shows that a low end-encapsulation rate (EC%) and, consequently, a high content of terminal hydroxyl groups, leads to increased peel strength. The data further suggests that, at terminal hydroxyl group content below approximately 700 ppm, the cooling time of the injection-molded sample before coating is not significantly related. The reason for this effect is not fully understood. It can also be understood that the adhesion of the coating decreases when the polycarbonate molding is cooled for a longer period.

[0064] The inventors also attempted to conduct a peel test using polycarbonate manufactured by an interfacial process, i.e., polycarbonate with sufficient end protection. The coating peeled off very easily, and as a result, the peel strength could not be measured.

[0065] Apart from the improvement in adhesive strength, the inventors also found that the impact characteristics of articles according to the present invention were improved compared to polycarbonate molded products provided by conventional acrylic or siloxane coatings, such as hard coats or UV-cured coatings. This finding was based on testing of several samples using the so-called "drop tower test procedure" according to ISO 6603-A, in which the coated side was the impact side. In particular, the inventors found that a 3.6 mm thick polycarbonate panel, prepared from molten polycarbonate with an MVR of 21 cm³ / 10 min, an end sealing rate of 75%, and a fleece content of 1050 ppm, coated with the same coating as Examples E1-E3, exhibited maximum ductile fracture in impact tests. No brittle fracture was observed. In contrast, corresponding articles with a hard coat coating layer or a UV-cured coating layer exhibited only brittle fracture. This embodiment is very important for the use of coated articles as front panels of (electric) vehicles.

Claims

1. An article comprising a carrier provided at least partially with a coating layer, - The carrier comprises or consists of a thermoplastic composition, and the thermoplastic composition comprises polycarbonate. - The coating layer is applied directly to the carrier and contains, or is made of, a polyurethane obtained by reacting at least one polyisocyanate with at least one polyol. The polycarbonate comprises at least 50% by weight of a first polycarbonate having a terminal hydroxyl content of at least 500 ppm, preferably at least 700 ppm, as measured according to the method described herein, based on the weight of the polycarbonate. An article comprising a polymer selected from the group consisting of polyethylene terephthalate, polybutylene terephthalate, acrylonitrile-butadiene-styrene copolymer, styrene-acrylonitrile copolymer, optionally functionalized polypropylene, optionally functionalized polyethylene, optionally functionalized polyolefin elastomer, (meth)acrylic acid-polybutadiene core-shell copolymer, and a mixture of at least two of the above.

2. The article according to claim 1, wherein the polycarbonate comprises at least 75% by weight, preferably at least 90% by weight, and more preferably at least 95% by weight of the first polycarbonate.

3. The article according to claim 1 or 2, wherein the first polycarbonate is molten polycarbonate.

4. The aforementioned polycarbonate, when measured according to ISO 1133 (1.2 kg, 300°C), has a thickness of 5 to 40 cm². ３ An article according to any one of claims 1 to 3, having a melt volume rate of 10 minutes.

5. The article according to any one of claims 1 to 5, wherein the thermoplastic composition comprises at least 95% by weight, preferably at least 98% by weight, of polycarbonate, based on the weight of the thermoplastic composition.

6. The article according to any one of claims 1 to 6, wherein the polycarbonate composition essentially consists of a bisphenol A polycarbonate homopolymer.

7. The article according to any one of claims 1 to 7, wherein the thermoplastic composition does not contain an antistatic agent.

8. The article according to any one of claims 1 to 8, wherein the polyurethane has an isocyanate index defined in the specification, of 0.90 to 1.2, preferably 0.95 to 1.

1.

9. The article according to any one of claims 1 to 8, wherein the polyisocyanate is diisocyanate or triisocyanate.

10. The article according to any one of claims 1 to 9, wherein the coating thickness, when measured after curing, is at least 50 μm, preferably at least 100 μm, more preferably at least 250 μm, and a maximum of 5000 μm, preferably a maximum of 4000 μm, and more preferably a maximum of 2500 μm.

11. The article according to any one of claims 1 to 10, wherein the article is an interior vehicle article or an exterior vehicle article.

12. A front panel for an electric vehicle comprising, or consisting of, the article described in any one of claims 1 to 11.

13. A vehicle, preferably an electric vehicle, comprising an article described in any one of claims 1 to 11, or a front panel made of the article, wherein the front panel is a panel facing forward of the vehicle.

14. i) The step of forming the carrier by injection molding by injecting a certain amount of thermoplastic composition into a mold, ii) A step of cooling the injection-molded article, iii) The step of directly applying a two-component polyurethane coating containing at least one polyisocyanate and at least one polyol to at least a portion of the injection-molded article, iii) a step of curing the coating, A method for producing an article according to any one of claims 1 to 11, wherein the thermoplastic composition comprises polycarbonate, and the polycarbonate comprises at least 50% by weight of a first polycarbonate having a terminal hydroxyl content of at least 500 ppm, preferably at least 700 ppm, based on the weight of the polycarbonate.

15. The method according to claim 14, further comprising the step of transferring the cooled, injection-molded article from step ii) to a second cavity before applying the coating in step iii).

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