Antiviral and antibacterial coating composition for vehicle interior trim part and associated part and method of manufacturing the same

Abstract

Antiviral and antibacterial coating composition for vehicle interior trim part and associated part and method for manufacturing the same The invention relates to an antiviral and antibacterial coating composition for a vehicle interior trim part (10), comprising by weight: - from 50 to 86% of a binding agent, the binding agent comprising a matrix polymer selected from polyols and a mixture thereof; - from 10 to 30% of an active agent, the active agent being selected from quaternary ammonium salts and a mixture thereof; and - from 4 to 10% of a curing agent. Figure for abstract: Figure 1

Description

Title of the invention: Antiviral and antibacterial coating composition for vehicle interior trim part and associated part and method of manufacturing the same

[0001] The present invention relates to an antiviral and antibacterial coating composition, in particular for the manufacture of vehicle parts, more particularly in the automotive field.

[0002] The invention also relates to the use of said composition for the manufacture of a vehicle interior trim part, as well as a vehicle interior trim part obtained using such a composition and its manufacturing method.

[0003] In order to prevent the spread of disease in a pandemic context such as that of the Sars-CoV-2 virus associated with the Covid-19 disease, or to combat episodes of influenza, gastroenteritis, bacterial proliferation, etc., and more generally to improve hygiene inside a vehicle, it may be necessary to regularly disinfect the interior elements of the vehicle, in particular the external surfaces of seats, door panels and / or dashboards with which passengers of the vehicle frequently come into contact.

[0004] This is particularly necessary in the case of shared vehicles, such as rental vehicles, chauffeur-driven vehicles or taxis. A large number of different passengers are likely to use such vehicles.

[0005] Sanitizing or disinfecting surfaces in a vehicle interior has traditionally been performed manually, by applying an external disinfectant, such as spraying a disinfectant aerosol onto or wiping surfaces with a disinfectant-saturated disposable cloth. Such techniques, however, are expensive, time-consuming, prone to human error, and often not environmentally friendly.

[0006] Another option is to apply UV-C light to the surfaces to inactivate the virus. UV-C lamps are then installed temporarily or permanently in the vehicle. Although this option is effective, it has several disadvantages. Several applications may be required, during which no one may be inside the vehicle. In addition, the lamps do not deliver a homogeneous dose of UV-C energy to all surfaces to be disinfected and some hidden areas are not disinfected. In addition, high radiation doses for surfaces close to the lamps can lead to accelerated degradation (i.e. aging) of said surfaces.

[0007] One of the aims of the invention is to overcome the aforementioned drawbacks by proposing a solution for the disinfection of a vehicle interior trim part which is effective in the treatment of surfaces, in particular polymer parts, autonomous and safe, and easy to integrate.

[0008] For this purpose, the invention relates to an antiviral and antibacterial coating composition for vehicle interior trim parts, comprising by weight:

[0009] - from 50 to 86% of a binding agent, the binding agent comprising a polymer matrix selected from polyols and a mixture thereof;

[0010] - from 10 to 30% of an active agent, the active agent being chosen from ammonium salts quaternary and a mixture thereof; and

[0011] - from 4 to 10% of a hardening agent.

[0012] The inventors found that the active agent acts as a trap for bacteria and viruses and prevents them from attaching to a living cell.

[0013] The coating composition according to the invention may comprise one or more of the following characteristics, taken alone, or in any technically feasible combination:

[0014] - the active agent is chosen from dimethyloctadecyl chloride[3-(trimethoxysilyl) -propyl] ammonium and 3-(trimethoxysilyl)-propyldimethylocadecyl ammonium chloride and a mixture thereof;

[0015] - the matrix polymer is chosen from polyurethanes, polysiloxanes and a mixture of these;

[0016] - the curing agent is chosen from hydrophilic aliphatic polyisocyanate, hexamethylene diisocyanate and a mixture thereof.

[0017] The invention also relates to the use of a coating composition of the aforementioned type for the manufacture of an interior vehicle trim part.

[0018] The invention also relates to a vehicle interior trim part comprising:

[0019] - a substrate made of a polymer material; and

[0020] - a coating layer obtained by applying a coating composition of the aforementioned type on a surface of the substrate.

[0021] According to a preferred embodiment, the substrate is a polypropylene substrate, preferably an injected polypropylene substrate.

[0022] The invention also relates to a method of manufacturing a vehicle interior trim part of the aforementioned type comprising the following steps:

[0023] - the provision of the substrate;

[0024] - the application of a coating composition of the aforementioned type on a substrate surface; and

[0025] - curing the coated substrate to obtain the coating layer.

[0026] The method according to the invention may comprise one or more of the following characteristics, taken alone or in any technically feasible combination:

[0027] - the coating composition is applied to the surface of the substrate by spraying;

[0028] - the method further comprises a surface activation step before application coating, in which the surface to be coated is flamed.

[0029] The invention will be better understood from the following description, given solely by way of example and made with reference to the appended drawing in which:

[0030] [Fig-1] [Fig.l] is a schematic sectional view of an interior trim piece vehicle according to the invention.

[0031] An interior trim part 10 of a vehicle according to the invention is shown in [Fig.l].

[0032] The vehicle interior trim piece 10 is intended to be arranged inside a vehicle, in particular inside a motor vehicle.

[0033] The vehicle interior trim part 10 is for example an interior trim part, such as a dashboard, a dashboard insert, a center console or a door panel.

[0034] The vehicle interior trim part 10 comprises a substrate 12 made of a polymer material, preferably a thermoplastic material, and a coating layer 14 disposed on an external surface 120 of the substrate 12.

[0035] The substrate 12 gives the interior trim part 10 its shape and also provides some of its mechanical properties, in particular its rigidity. For example, the rigid substrate 12 has a three-dimensional shape.

[0036] The substrate 12 is made of a substantially rigid material, such as a plastic or composite material. As a result, the rigid substrate 12 has a stable shape with substantially stable dimensions under normal conditions of use, i.e. when normal stresses during use of the vehicle are applied to the substrate 12.

[0037] The substrate 12 is preferably made of a polyolefin material, more preferably polypropylene.

[0038] For example, the substrate 12 is an injected thermoplastic substrate, more preferably an injected polypropylene substrate.

[0039] Alternatively, the substrate 12 is a thermoplastic part, notably a polypropylene part, covered with a sheet consisting for example of thermoplastic polyolefin (TPO) and / or polyvinyl chloride (PVC).

[0040] The coating layer 14 covers at least a portion of the substrate 12, advantageously the entire substrate 12. Preferably, the coating layer 14 covers the surfaces of the substrate 12 accessible by a passenger of the vehicle and that a passenger can touch once the interior trim piece 10 is installed in the vehicle.

[0041] Preferably, the coating layer 14 has a thickness eu of between 5 and 30 μm.

[0042] Preferably, the coating layer 14 has a surface mass of between 2 and 8 g / m2, preferably between 3 and 6 g / m2 and more preferably between 4 and 5 g / m2.

[0043] The coating layer 14 comprises an active agent having antiviral and antibacterial properties.

[0044] The coating layer 14 is formed directly on an external surface 120 of the substrate 12 or on a primer layer applied to said surface 120.

[0045] The coating layer 14 is obtained by applying a coating composition according to the invention.

[0046] Said coating composition is water-based and comprises, by weight:

[0047] (a) from 50 to 86% of a binding agent;

[0048] (b) from 10 to 30% of an active agent; and

[0049] (c) from 4 to 10% of a curing agent.

[0050] Preferably, the coating composition comprises from 60 to 85%, more preferably from 65 to 80%, even more preferably from 74 to 78% by weight of the bonding agent.

[0051] By "binding agent" is meant in the context of the invention compounds capable of crosslinking the active ingredient with the substrate and holding all the materials together through chemical reactions, to form a cohesive coating.

[0052] The binding agent is a polymer matrix solution comprising at least one polyol.

[0053] For example, the bonding agent is chosen from polyurethanes and polysiloxanes, preferably from polyoxyethylene alkyl ether and polysiloxane fluoropolymer and mixtures thereof.

[0054] Preferably, the coating composition comprises from 10 to 30%, more preferably from 14 to 20%, even more preferably from 15 to 19% by weight of the active agent.

[0055] By "active agent" is meant in the context of the invention compounds having antiviral and / or antibacterial activity.

[0056] According to the invention, the active agent is a cationic antiviral agent.

[0057] More particularly, the active agent is chosen from quaternary ammonium salts and their mixture.

[0058] Quaternary ammonium salts have the general formula RiR2R3R4N+X , with X representing a halogen atom, such as F, Cl, Br, or I and Ri, R2, R3 and R4, which may be the same or different, independently represent a saturated or unsaturated, linear or branched or cyclic hydrocarbon chain, optionally substituted by one or more functional groups and optionally comprising one or more heteroatoms.

[0059] For example, RB R2, R3 and R4 can be chosen from CH3, CH3(CH2)X with x ranging from 1 to 25, and (CH2)3Si(OCH3)3

[0060] Preferably, Ri corresponds to CH3, R2 corresponds to CH3(CH2)i7, R3 corresponds to CH3, R4 corresponds to (CH2)3Si(OCH3)3.

[0061] Preferably, Rb R2, R3 and R4 independently represent an aromatic or aliphatic hydrocarbon chain.

[0062] Preferably, said hydrocarbon chain is a C1 to C100 hydrocarbon chain, more preferably a C1 to C25 hydrocarbon chain.

[0063] Specific examples of quaternary ammonium salts that are suitable for use in the present invention include, without limitation, tetraalkylammonium salts, trialkylammonium salts, dialkyldiarylammonium salts, alkyltriarylammonium salts, tetraarylammonium salts, cyclic ammonium salts, and dicyclic ammonium salts.

[0064] Preferably, the active agent is selected from dimethyloctadecyl[3-(trimethoxysilyl)-propyl] ammonium chloride and 3-(trimethoxysilyl)-propyldimethylocadecyl ammonium chloride and mixtures thereof.

[0065] Without wishing to be bound by any particular theory, the inventors assume that quaternary ammonium salts attract viruses, which have a negative charge, and hold them on the coated surface, thus inactivating them. The viruses can no longer attach to a living cell and eventually die.

[0066] Preferably, the coating composition comprises from 4 to 10%, more preferably from 5 to 9% and even more preferably an amount equal to 7% by weight of the curing agent.

[0067] By "curing agent" is meant in the context of the invention compounds capable of increasing the viscosity of a liquid without substantially changing their other properties or compounds capable of producing the curing of the coating due to the catalysis of the composition.

[0068] The curing agent is for example chosen from the group of aliphatic isocyanates.

[0069] For example, the curing agent is selected from hydrophilic aliphatic polyisocyanate and hexamethylene diisocyanate and mixtures thereof.

[0070] Optionally, the coating layer 14 also comprises pigments and / or additives. Pigments may be used to color the coating layer 14 to a desired color and enhance its appearance. Additives may increase resistance to UV, chemicals, abrasion, and / or moisture.

[0071] A process for preparing a coating composition as defined above will now be described. Said process comprises mixing its components.

[0072] A first solution comprising the binding agent is first prepared and stirred at room temperature, notably at 23°C.

[0073] The active agent and the curing agent are then added to the first solution, preferably by stirring the first solution.

[0074] In a preferred embodiment, the active agent is first introduced into the first solution in the form of a solution comprising the active agent and a first curing agent. A second curing agent, the same as or different from the first curing agent, is then introduced.

[0075] For example, the first curing agent is selected from (3-chloropropyl)trimethoxysilane and 3-(trimethoxysilyl)-propylamine and the second curing agent is selected from hydrophilic aliphatic polyisocyanate and hexamethylene diisocyanate.

[0076] The composition is then stirred for 2 to 10 minutes, preferably for 5 minutes.

[0077] The coating composition obtained preferably has a density of between 0.75 g / cm3 and 1.25 g / cm3, more preferably between 0.90 g / cm3 and 1.10 g / cm3.

[0078] The coating composition preferably has a solid volume value of between 10% and 30%, preferably between 20% and 25%.

[0079] These parameters allow easy deposition of the coating deposit on the surface to be coated.

[0080] The coating composition obtained can be maintained at least for 6 hours at 20°C and at least for 4 h at 27°C.

[0081] A method of manufacturing a vehicle interior trim part as defined above will now be described.

[0082] First, the substrate 12 is provided. For example, the substrate 12 is obtained by melting pellets of polymeric material, preferably polypropylene, and molding the molten material in a molding apparatus to obtain a substrate having the desired shape.

[0083] In a preferred embodiment, the surface of the substrate 12 to be coated is then subjected to a pretreatment to activate the surface. For example, the pretreatment is selected from flame treatment, corona discharge, treatment UV, plasma activation, mechanical processes such as frosting, sandblasting, and chemical processes such as etching.

[0084] Advantageously, the surface to be coated is flamed.

[0085] The coating composition is then applied to the surface of the substrate 12.

[0086] Advantageously, the coating composition is applied directly to the external surface 120 of the substrate 12. By “directly” is meant that no primer composition has been previously applied to the external surface 120 of the substrate 12. The process is therefore shorter and less expensive.

[0087] The coating composition may be applied by spraying, vapor deposition, roller application such as roller coating.

[0088] Advantageously, the coating composition is sprayed onto the surface of the substrate 12.

[0089] Next, the coated substrate 12 is cured, preferably at a temperature ranging from 60°C to 100°C, the heating time preferably being between 5 min and 15 min.

[0090] For example, the coated substrate 12 is oven cured at 80°C for 10 minutes.

[0091] The vehicle interior trim part 10 is thus obtained comprising the substrate 12 and the coating layer 14 according to the invention. Example

[0092] A CC coating composition was prepared by mixing the following components:

[0093] [TABLE 1]: Composition of the coating composition Component Proportion (% by weight) A Polyoxyethylene alkyl ether + Fluoropolymer (bonding agent) 76 B Dimethyloctadecyl (3-(trimethoxy silyl) propyl) ammonium chloride (active agent) + 3-chloropropyltrimethoxysilane and 3 (Trimethoxysilyl)propylamine (curing agent 1) 17 C Hydrophilic aliphatic polyisocyanate + hexamethylene diisocyanate (curing agent 2) 7

[0094] Component A was first placed in a container and stirred by a magnetic stirrer to create a vortex on the surface. Then, components B and C were added and the mixture was allowed to stir at 500 rpm for 5 minutes.

[0095] The resulting CC coating composition had a density of 1.01 g / cm3 and a solid volume value of 22.4% by volume.

[0096] The density of the composition was measured by pycnometer.

[0097] The solid volume value of the composition was measured with a test tube graduated by water displacement.

[0098] Next, the CC coating composition was spray-applied onto the surface of a previously flame-treated injected polypropylene substrate. The coated substrate was then cured in an oven at 80°C for 10 minutes.

[0099] A coated part with a coating layer 5 μm thick was thus obtained.

[0100] Said part has shown excellent antibacterial properties against Gram-positive organisms (Staphylococcus Aurus, Streptococcus, Listeria, etc.) and Gram-positive organisms (Escherichia Coli, Salmonella, Yersinia pestis, etc.).

[0101] The antiviral and antibacterial properties of the part were measured according to ISO 22196:2011 (Measurement of antibacterial activity on plastics and other non-porous surfaces).

[0102] During the test, a thin liquid layer containing bacteria (Staphylococcus Aurus or Escherichia Coli) was applied directly to the coated surface of the part defined above.

[0103] For each type of bacteria, the number of germs (CFU, for colony forming unit) was immediately measured in a control sample to determine the initial CFU.

[0104] Another sample for each bacterium was then incubated in a humid environment at 35 °C, with a relative humidity greater than 95%. After 24 hours, surviving bacteria were removed from the sample surfaces and the number of germs (final CFU) was determined.

[0105] [TABLE 2]: Antibacterial properties Culture media Organism Initial CFU (Oh) Final CFU (2 4 h) % reduction Antimicrobial activity Agar E. Coli 1.5.104 < 1.0 99.9997% excellent Agar S.Aurus 1.5.104 < 1.0 99.9997% excellent

[0106] As seen in Table 2, the coating composition exhibits excellent antibacterial properties for both types of bacteria.

[0107] No change in visual or haptic appearance was observed compared to uncoated parts.

[0108] Antiviral properties after aging were also measured.

[0109] A coated part was prepared according to the above protocol and was then subjected to a heat treatment simulating aging. The coated part was heated in a climate aging cycle of 90°C for 16 hours, with 0% relative humidity, then 55°C for 48 hours, with 95% relative humidity, then 30°C for 16 hours, with 0% relative humidity, then 100°C for 16 hours, with 0% relative humidity.

[0110] The antiviral properties of the part were then measured according to ISO 21702:2019 (Measurement of antiviral activity on plastics and other non-porous surfaces). [YES] [TABLE 3]: Antiviral properties Viral strain Contact time Temperature Relative humidity % reduction HCoV-229E 8 hours 55°C 95% 99%

[0112] As seen in Table 3, even after aging, virus reduction was still excellent.

[0113] The coating composition according to the invention shows long-lasting antiviral properties after aging.

[0114] The durability of the coating was also studied by carrying out various abrasion and scratch tests on a coated part before and after a certain climatic aging.

[0115] Aging was simulated by subjecting the coated part to 40°C for 240 h and saturated relative humidity or by subjecting the coated part to 90°C for 72 h with 95% relative humidity.

[0116] The abrasion test is carried out using a crockmeter according to DIN EN ISO 105-X12 (2016). The scratch test is carried out using a 430 P scratch hardness tester and the measuring method is carried out according to DIN EN ISO 11664-3 (2019).

[0117] Even after aging, the coated part showed good resistance to abrasion and scratching.

Claims

Claims

1. An antiviral and antibacterial coating composition for a vehicle interior trim part (10), comprising by weight: - from 50 to 86% of a binding agent, the binding agent comprising a matrix polymer comprising at least one polyol; - from 10 to 30% of an active agent, the active agent being selected from quaternary ammonium salts and a mixture thereof; and - from 4 to 10% of a curing agent.

2. The coating composition of claim 1, wherein the active agent is selected from dimethyloctadecyl[3-(trimethoxysilyl)-propyl] ammonium chloride and 3-(trimethoxysilyl)-propyldimethyloctadecyl ammonium chloride and a mixture thereof.

3. A coating composition according to claim 1 or 2, wherein the bonding agent is selected from polyurethanes and polysiloxanes.

4. A coating composition according to any preceding claim, wherein the curing agent is selected from hydrophilic aliphatic polyisocyanate, hexamethylene diisocyanate and a mixture thereof.

5. Use of a coating composition according to any one of claims 1 to 4 for the manufacture of an interior trim part (10) of a vehicle.

6. Interior trim part (10) of a vehicle, comprising: - a substrate (12) made of a polymer material; and - a coating layer (14) obtained by applying a coating composition according to any one of claims 1 to 4 on a surface (120) of the substrate (12).

7. A vehicle interior trim piece (10) according to claim 6, wherein the substrate (12) is a polypropylene substrate, preferably an injected polypropylene substrate.

8. A method of manufacturing an interior trim part (10) of a vehicle according to claim 6 or 7, comprising the following steps: - providing the substrate (12); - applying a coating composition according to any one of claims 1 to 4 to a surface (120) of the substrate (12); and - curing the coated substrate to obtain the coating layer (14).

9. The method of claim 8, wherein the coating composition is applied to the surface (120) of the substrate (12) by spraying.

10. The method of claim 8 or 9, further comprising a surface activation step prior to coating application, wherein the surface (120) to be coated is flamed.

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