Solution based chemical resistant PVDF acrylic clear coat film and method of making

Abstract

The present disclosure relates to a solution based polyvinylidene fluoride (PVDF) and acrylic clear coat film and its application as a weatherable topcoat with improved chemical resistance which can, e.g., satisfy chemical resistance requirements of automotive interior parts. The present disclosure also describes methods of making the chemical resistant clear coat film and laminates comprising the clear coat film.

Description

[0001] SOLUTION BASED CHEMICAL RESISTANT PVDF ACRYLIC CLEAR COAT FILM AND METHOD OF MAKING Field of the invention The present disclosure relates to a solution based polyvinylidene fluoride (PVDF) and acrylic clear coat film, method of making such film, and its application as a topcoat with improved chemical resistance, weatherability, formability and good adhesion to fluoropolymers, polyurethanes and other polymers. The present disclosure also describes methods of applying the clear coat on bright and paint films to satisfy chemical resistance requirements of, e.g., automotive interior parts. Background of the invention Decorative polymeric components have become standard in the automobile industry, primarily because polymers are relatively flexible, corrosion-resistant, and inexpensive. Polymeric parts also reduce vehicle weight, which enhances performance, especially fuel economy. Polymeric structures having metallized finishes are now commonly used as substitutes for articles that are expected to have a chrome-plated appearance, such as automobile grilles, door frames, dash boards, instrument consoles, badges, logos, signages, and other exterior and interior decorations. Along with this transition to polymeric components, decorative film and film laminates have been replacing conventional in situ methods of coating automotive body or interior parts to provide decorative surface finishes. For example, instead of spraying decorative paint onto a part, decorative film can be thermoformed onto a part through a three-dimensional overlay method (“TOM”) or form over part (“FOP”) process. Decorative paint film laminates can be thermoformed and / or injection molded into a part to provide gloss, color, and weatherability to the surface of the part. Instead of directly coating metal onto a molded substrate, usually by vacuum deposition, metallized film laminates can be formed onto a part to provide a metallized polymeric finish and can complement and even replace bright, reflective metal surface treatments, particularly chrome plating. A clear coat film oftentimes forms part of the film laminate as a topcoat, or outwardly facing layer, of the laminate. It is desirable that the clear coat film be substantially transparent while imparting weathering and chemical resistance. Depending on the application, the clear coat film may need to be formed from a polymer composition selected to provide a film which will not significantly fade, peel, crack, or chalk when exposed to the environment for the intended life of the part. It may also need to fulfill other desired characteristics such as UV resistance, toughness, scratch resistance, and mar resistance. Additionally, the clear coat film is desirably formable from a two-dimensional surface to a three-dimensional surface without objectionable loss of appearance or performance properties. Certain applications for film and film laminates, such as automotive interior applications, require, among other things, resistance to chemicals present in sunscreen lotions, such as octyl methoxycinnamate, octocrylene, avobenzone, para aminobenzoic acid, homosalate, titanium dioxide, zinc oxide, benzophenones, benzylidenes, salicylates, oxybenzone, phenylbenzimidazole sulfonic acid, oxybenzone, and / or other known UV filters, and chemicals present in insect repellents, such as N, N diethyl-meta- toluamide (DEET). Commonly used clear coats are formed from alloys of a fluoropolymer, such as polyvinylidene fluoride (PVDF), and an acrylic polymer. Such clear coat films are typically cast from dispersions of PVDF and (meth)acrylic mixtures. Higher amounts of PVDF typically increase the chemical resistance of a PVDF / acrylic coating. However, coatings containing high concentrations of dispersion-based PVDF have increased haze and reduced clarity and transparency. Clear coat films for high reflective surface finishes such as chrome finishes require low haze, high clarity, and transparency. While these properties may be achievable in clear coat films made with dispersions having a low PVDF content, e.g., 50 wt% or lower, such levels compromise the chemical resistance of the coating. For example, such clear coat films have poor resistance to chemicals such as sunscreen lotion and insect repellents, particularly those containing N,N-diethyl-meta-toluamide (DEET). Clear coats cast from solutions are also known. In EP 0 285 071 A2 is for example disclosed a thermofoldable laminate for use on an exterior car body panel comprising an exterior clear coat above a color coat. The clear coat comprises a thermoplastic paint system containing 50-70 wt% PVDF and 30-50 wt% acrylic resin. The PVDF and acrylic resin are dissolved in a mixture of ketones and then applied by reverse roll coater on a carrier. In WO 00 / 78538 A1 is disclosed a multilayer decorative sheet useful in vehicles comprising a clear coat with appearance properties for exterior automotive use. The clear coat comprises a blend of preferably 50 to 75 wt% PVDF and 25 to 50 wt% acrylic resin. The PVDF and acrylic- based clear coat can be prepared as a solution or as a dispersion of PVDF in a solution of acrylic resin. In the example, a mixture of ketones and an acetate ester as co-solvent are used as solvent for the PVDF and acrylic resin. A disadvantage of solutions of PVDF / acrylic with a relatively high PVDF content in ketone solvents is that such solutions must be heated to obtain a substantially clear solution. This may give rise to storage and shelf-life issues. In US 2010 / 310880 is disclosed the use of lactam solvent for PVDF / acrylic systems in order to obtain a clear solution at room temperature. Lactam solvent, however, has toxicological risks and other disadvantages. Therefore, there is a need for a clear coat film having substantial clarity while demonstrating excellent chemical resistance, weatherability, formability and good adhesion to polymers such as fluoropolymers and polyurethanes, that is formed from a composition that can be stored at room temperature. Summary The present inventors have found a solution based PVDF / acrylic clear coat film which has the desired clarity and transparency, formability and weatherability while demonstrating improved chemical resistance. In a first aspect, the present disclosure provides a chemical resistant clear coat film wherein the film is formed from a solution of polyvinylidene fluoride (PVDF) homopolymer and (meth)acrylic (co)polymer in a solvent system comprising dimethyl sulfoxide and ketone, wherein the weight ratio of PVDF homopolymer to (meth)acrylic (co)polymer in the clear coat film is 58:42 or greater. In certain embodiments, the weight ratio of PVDF homopolymer to (meth)acrylic (co)polymer in the clear coat film is 58:42 to 75:25. In some embodiments, the solution further comprises a crosslinker capable of crosslinking the (meth)acrylic (co)polymer. In certain embodiments, the ketone is selected from a group consisting of dimethyl ketone (acetone), diethyl ketone, methyl ethyl ketone (MEK), methyl isobutyl ketone, optionally substituted or unsubstituted cyclohexanone, such as trimethylcyclohexanone (TMCHONE), cyclopentanone, and mixtures thereof. In some embodiments, the clear coat film may comprise UV absorbers and / or hindered amine light absorbers (HALS). The clear coat film may have a total haze value of 1 or less as measured by ASTM D1003, and a chemical resistance rating of 2 or less as measured by GM standard test method GMW14445. The clear coat film may have a total haze value of 1 or less as measured by ASTM D1003, and a chemical resistance rating of 2 or less as measured by Ford standard test method BI 113-08. The present disclosure also provides a film comprising the chemical resistant clear coat film and one or more additional film layers. The one or more additional film layers may be a metallized film layer or a paint film layer. In certain embodiments, the chemical resistant clear coat film is the topcoat in the film. The present disclosure also provides an article comprising a carrier at least partially coated with the chemical resistant clear coat film. In a further aspect, the present disclosure provides a film laminate comprising a substrate; and a chemical resistant clear coat film formed from a solution of polyvinylidene fluoride (PVDF) homopolymer and (meth)acrylic (co)polymer in a solvent system comprising dimethyl sulfoxide and ketone, wherein the weight ratio of PVDF homopolymer to (meth)acrylic (co)polymer in the clear coat film is 58:42 or greater, wherein the clear coat film is coated on at least a portion of the substrate. In some embodiments, the film laminate may comprise one or more film layers disposed between the substrate and the chemical resistant clear coat film. The one or more film layers may comprise a metallized film layer. The one or more film layers may comprise a pigmented paint film layer. In another aspect, the present disclosure provides a method of making a chemical resistant clear coat film. Said method comprises the steps of dissolving a polyvinylidene fluoride (PVDF) homopolymer and (meth)acrylic (co)polymer in a solvent system comprising dimethyl sulfoxide and ketone to form a solution, wherein the weight ratio of PVDF homopolymer to (meth)acrylic (co)polymer in the solution is 58:42 or greater; casting the solution onto a base layer; and drying the solution to form the clear coat film. In some embodiments, the base layer is a carrier. In certain embodiments, the base layer is a paint film layer. In some embodiments, the base layer may be a metallized film layer. In one embodiment, the clear coat film has a total haze value of 1 or less as measured by ASTM D1003, and a chemical resistance rating of 2 or less as measured by GM standard test method GMW14445. In another exemplary embodiment, the clear coat film has a total haze value of 1 or less as measured by ASTM D1003, and a chemical resistance rating of 2 or less as measured by Ford standard test method BI 113-08. Brief Description of Drawings A full understanding of the invention can be gained from the following description of certain embodiments of the invention when read in conjunction with the accompanying drawings in which: FIG.1 is a cross-sectional view of a bright metallized laminate having the chemical resistant clear coat film of the present disclosure as a topcoat. FIG.2 is a cross-sectional view of a paint film laminate having the chemical resistant clear coat film of the present disclosure as a topcoat. FIG.3 is a schematic illustration of a process for manufacturing a paint film laminate as described in the present disclosure. Detailed description of the invention The following description of the preferred embodiment(s) is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses. As used herein, the following terms have the designated definitions, unless the context clearly indicates otherwise. As used herein, the singular forms "a”, “an” and “the” include plural referents unless the context clearly dictates otherwise. For example, although reference is made herein to “a” ketone, “a” (meth)acrylic (co)polymer, “an” amino moiety, a combination (a plurality) of each of these components can be used in the present disclosure unless the context clearly dictates otherwise. As used herein, “plurality” means two or more. The terms “comprising”, “comprises” and “comprised of” as used herein are synonymous with “including”, “includes”, “containing” or “contains”, and are inclusive or open-ended and do not exclude additional, non- recited members, elements or method steps. If used, the phrase “consisting of” is closed and excludes all additional elements. Further, the phrase “consisting essentially of” excludes additional material elements but allows the inclusion of non-material elements that do not substantially change the nature of the invention. When referring to any numerical range of values, such ranges are understood to include each and every number and / or fraction between the stated range minimum and maximum. For example, a range of “1 to 10” is intended to include all sub-ranges between (and including) the recited minimum value of 1 and the recited maximum value of 10, that is, having a minimum value equal to or greater than 1 and a maximum value of equal to or less than 10. When amounts, concentrations, dimensions and other parameters are expressed in the form of a range, a preferable range, an upper limit value, a lower limit value or preferable upper and limit values, it should be understood that any ranges obtainable by combining any upper limit or preferable value with any lower limit or preferable value are also specifically disclosed, irrespective of whether the obtained ranges are clearly mentioned in the context. The words “preferred”, “preferably”, “desirably” and “particularly”, and synonyms thereof, are used frequently herein to refer to embodiments of the disclosure that may afford particular benefits, under certain circumstances. However, the recitation of one or more preferable, preferred, desirable or particular embodiments does not imply that other embodiments are not useful and is not intended to exclude those other embodiments from the scope of the disclosure. Molecular weights are on a number average or weight average basis as indicated and are determined by gel permeation chromatography using tetrahydrofuran as a solvent and using polystyrene standards. The terms “acrylate” and “acrylic” are used broadly (and interchangeably) herein and encompass materials prepared from, for example, one or more of acrylic acid, methacrylic acid, or any acrylate or methacrylate compound. Thus, for example, a homopolymer consisting entirely of polymerized (meth)acrylic acid would still be an “acrylate” polymer even though no (meth)acrylate monomer was employed. The term “carrier” as used herein refers to a base plastic film onto which a coating is cast. The carrier can comprise a polyester casting film, such as polyethylene terephthalate (PET) film, or a biaxially oriented polypropylene (BOPP) film, etc. As used herein, “curing” and like terms as used herein, refers to a process of setting or drying of a material to form a coating on a carrier, film, base layer, or substrate. As used herein, the term "dispersion" refers to a finely divided solid or liquid in a continuous liquid medium. An aqueous dispersion is a dispersion in which the continuous liquid medium is water. As used herein, “formable” with respect to a layer, means that the layer can be formed, shaped or molded from a two-dimensional surface to a three-dimensional surface without objectionable loss of appearance or performance properties. As used herein, “homopolymer” refers to a polymer formed from a single type of monomer. As used herein, “insect repellent” refers to a composition that repels insects that can be applied to the skin. Such composition can be in lotion, gel or liquid form and can be applied manually or via spray or aerosol. Such composition can comprise N, N diethyl-meta-toluamide (DEET) in amounts of 20-30%. The term “on”, when used in the context of a coating applied on a surface or substrate, includes both coatings applied directly or indirectly to the surface or substrate. Thus, for example, a coating applied to a primer layer overlying a substrate constitutes a coating applied on the substrate. The term “(meth)” as used in “(meth)acrylate”, “(meth)acrylic acid”, and the like is intended to indicate that either a hydrogen or methyl group may be attached to the pertinent carbon atom of the monomer. For example, “(meth)acrylic” encompasses both acrylics and methacrylics, as well as mixtures thereof. Unless otherwise indicated, the term “polymer” includes both homopolymers and copolymers (e.g., polymers of two or more different monomers) and oligomers. Resin is used simultaneously with polymer. As used herein, “solution” refers to a homogenous mixture of two or more substances in relative amounts that can be varied continuously up to the limit of solubility. Unless otherwise indicated, the term “substrate” as used herein refers to the base material onto which a film (single or multi-layered) is laminated. A substrate can comprise, for example, acrylonitrile butadiene styrene copolymer (ABS), polycarbonate (PC), thermoplastic polyolefin (TPO), thermoplastic polyurethane (TPU), formable polyester, glass fiber-thermoset composites, polyvinyl Chloride (PVC), stainless steel and aluminum. As used herein, “sunscreen lotion” refers to a composition that contains a compound that absorbs, reflects, or scatters radiation in the UV range and that can be applied to the skin. The sunscreen lotion can be in the form of a lotion, a gel, a liquid, and can be applied manually or via spray or aerosol. The sunscreen lotion may contain octyl methoxycinnamate, octocrylene, avobenzone, para aminobenzoic acid, homosalate, titanium dioxide, zinc oxide, benzophenones, benzylidenes, salicylates, oxybenzone, phenylbenzimidazole sulfonic acid, oxybenzone, and / or other known UV filters. The sunscreen lotion can be waterproof. The sunscreen lotion may have an SPF of 15, or 30, or 45, 50 or as commercially available. Unless otherwise specified, the term “UV” is intended to mean ultraviolet. As used herein, “total haze value” refers to the sum of the internal haze and the surface haze. All percentages, ratios and proportions used herein are given on a weight basis unless otherwise specified. The present disclosure relates to a solution based clear coat film having improved chemical resistance. It has been surprisingly found that this clear coat film can be achieved by using a solution of polyvinylidene fluoride (PVDF) homopolymer rather than a dispersion of PVDF. By dissolving a polyvinylidene fluoride (PVDF) homopolymer in a solvent system comprising dimethyl sulfoxide and a ketone, a greater amount of PVDF can be incorporated into the solution to achieve a PVDF / acrylic clear coat that has chemical resistance to chemicals such as sunscreen lotion and insect repellant while maintaining desired clarity. Other properties, such as formability and weatherability, may also be retained. The clear coat can be used as a topcoat on a film laminate, such as paint film laminate or a metalized formable laminate. Clear Coat Film According to a first aspect, a chemical resistant clear coat film is provided wherein the film is based on a solution of polyvinylidene fluoride (PVDF) homopolymer and a (meth)acrylic (co)polymer in a solvent system comprising dimethyl sulfoxide and ketone, wherein the weight ratio of PVDF homopolymer to (meth)acrylic (co)polymer in the clear coat film is 58:42 or greater. It has been observed that while certain PVDF copolymers, such as Solef® 21510 / 1001 PVDF copolymer, available from Solvay, and Kynar® SL PVDF copolymer, available from Arkema, can be dissolved in common solvents to form clear coats, the chemical resistance of films formed from those solutions does not meet automotive specifications. It has also been observed that while PVDF homopolymers in dispersion may form clear coat films with good chemical resistance, these clear coat films have a total haze value greater than 1, which is unacceptable for certain automotive applications. The visual quality of high reflective chrome finishes suffers if the clear coat has any haze. While a higher amount of PVDF can improve the chemical resistance of a film in dispersion-based formulations, it can also reduce the transparency and clarity of the film. It has been surprisingly found that clear coat films based on a solution of PVDF homopolymer and (meth)acrylic (co)polymer in a solvent system comprising DMSO and ketone allows for incorporation of higher amounts of PVDF into the clear coat film, resulting in improved chemical resistance while maintaining desired levels of transparency and clarity, with very low total haze values (e.g., < 0.4). Use of solvents comprising DMSO and ketone for dissolving fluoropolymers as such has been disclosed in US 2014 / 100313. It is, however, surprising that such solvent when used for dissolving PVDF homopolymer and (meth)acrylic (co)polymer in a weight ratio of 58:42 or greater results in clear coat films that show, in combination, such improved chemical resistance and levels of transparency and clarity desired for use in interior and exterior automotive parts. The PVDF homopolymer used to make the clear coat film of the present disclosure can be selected from PVDF homopolymers known to those skilled in the art, such as those sold by Arkema as Kynar® 500 Plus and Kynar® 500 FSF PVDF, those sold by Solvay as Hylar® 5000S PVDF, or those sold by Gujarat Fluorochemicals as INOFLAR 5125. The PVDF homopolymer can have a melting point of 155°C or higher, or 155-178°C. The PVDF homopolymer can be present in the solution in amounts of up to 15 wt%. The (meth)acrylic (co)polymer used in the clear coat film can be a homopolymer or a copolymer, or mixtures thereof. The (meth)acrylic (co)polymer can be a resin that has properties that may improve certain properties of the solution or clear coat film formed therefrom, for example, adhesion promotion, viscosity control, hardness, scratch resistance, abrasion resistance, blocking resistance, outstanding clarity, and crosslinking functionalities. Commercially available (meth)acrylic (co)polymers are Elvacite® 2041, Elvacite® 2042, Elvacite® 2014, Elvacite® 2552, and BR85, all manufactured by Mitsubishi Chemical America, and Acryloid A11 manufactured by Dow Chemical. The (meth)acrylic (co)polymer can also be in solution. For example, the (meth)acrylic (co)polymer can be at 30-40 wt% in a solvent mixture, such as DuPont 68070 and 68080 acrylic adhesives. The (meth)acrylic (co)polymer can be present in the solution in amounts of up to 10 wt%, such as 4 wt% to 7 wt% based on the weight of the solution. In general, higher acrylic content offers greater scratch resistance, but at the cost of increased brittleness and less chemical resistance (especially to solvents). Including acrylic in polyvinylidene difluoride films is desirable, especially for metallized laminates incorporating the clear coat film, as 100 percent polyvinylidene difluoride films can cause the metallized laminate to appear somewhat cloudy. The ratio of PVDF homopolymer to (meth)acrylic polymer in the chemical resistant clear coat film of the present disclosure is 58:42 or greater. In some embodiments, the ratio can be 58:42 to 75:25. At ratios lower than 58:42, the film’s chemical resistance starts to deteriorate. Higher ratios may reduce other preferable properties, such as, gloss, hardness, and scratch resistance. The ketone in the clear coat composition of the present disclosure can be aliphatic, cycloaliphatic, aromatic, or mixtures of two or more of these types of ketones. The ketones can be linear or branched aliphatic and / or cycloaliphatic ketones and can be chosen from dimethyl ketone (acetone), diethyl ketone, methyl ethyl ketone (MEK), methyl isobutyl ketone, optionally substituted or unsubstituted cyclohexanone, such as trimethylcyclohexanone (TMCHONE), cyclopentanone, and others, and mixtures thereof. In certain embodiments, the weight ratio of DMSO to ketone in the clear coat solution can be, for example, 10:90 to 90:10, or 70:30 to 30:70. In certain embodiments, the total amount of solvent in the clear coat solution can be 80-90wt%. In some embodiments, the total amount of DMSO and ketone in the clear coat solution can range from 70 to 90 wt%, or 73 to 85wt%. The solvent system used for the solution of PVDF homopolymer and (meth)acrylic (co)polymer described in the present disclosure can be binary, i.e., consisting of DMSO and ketone. In another embodiment, the solvent system can be tertiary, comprising a third solvent. In other embodiments, the solvent system can have more than three solvents. These additional solvents can comprise 1-methoxy-2-propanol, diethylene glycol monobutyl ether acetate, 1-methoxy-2-propanol acetate, other glycol ethers, ethyl acetate, dimethyl glutarate, dimethyl adipate, dimethyl succinate, toluene, isopropyl alcohol, and propyl acetate. In certain embodiments, the total amount of DMSO plus ketone in the solvent system can range from 85 to 100 wt%, depending on whether there are other solvents present. In another embodiment, the clear coat film of the present disclosure can comprise other optional components. These optional components can be added to the solution of PVDF homopolymer and (meth)acrylic (co)polymer. In certain embodiments, the (meth)acrylic (co)polymer comprises crosslinkable functional groups such as OH-groups, carboxylic groups, or NH-groups. In such embodiments, the solution preferably comprises a crosslinker with crosslinkable functionalities, such as melamine, isocyanate, blocked isocyanate, and carbodiimide functionalities capable of crosslinking the (meth)acrylic (co)polymer(s) with hydroxyl, carboxylic, or NH- functionalities. Crosslinking the (meth)acrylic (co)polymers may further improve chemical, scratch and abrasion resistance of the clear coat film. It may also enhance adhesion to certain substrates in situations where the clear coat film is in direct contact with a substrate. For example, aminoplast resins, such as melamine resins, or blocked or unblocked polyisocyanates can be used as crosslinkers. Suitable melamine crosslinkers include Permuthane® XR-9116 crosslinker, available from Stahl, and Cymel® 303LF crosslinker, available from Allnex. Suitable isocyanates and blocked isocyanate crosslinkers include Desmodur 2489, Desmodur 2580, Desmodur BL 3272, and Desmodur BL 4265SN, all from Covestro Deutschland AG. Suitable carbodiimide crosslinkers include Permutex XR 5577 from Stahl. In one embodiment, the (meth)acrylic (co)polymer is an OH-functional (meth)acrylic (co)polymer and the solution comprises a crosslinker reactive with the OH-functionality of the (meth)acrylic (co)polymer. In some embodiments, the solution may also include other optional ingredients or additives that do not adversely affect the solution or the clear coat film formed therefrom. Such optional ingredients are typically included in a clear coat film to enhance film aesthetics, to facilitate manufacturing, processing, handling, and application of the solution or film, and to further improve a particular functional property of the solution or the film resulting therefrom. Such optional ingredients include, for example, UV absorbers, hindered amine light stabilizers, catalysts, lubricants, surfactants, anticorrosion agents, flow control agents, thixotropic agents, antioxidants, adhesion promoters, and mixtures thereof. For example, ultraviolet light absorbers, such as Tinuvin® 928, manufactured by BASF, can be added to the clear coat film to improve the weathering characteristics for its intended use. If present, these optional ingredients can be present in amounts up to 10 wt%, or up to 5 wt% of the dry film. It will be understood by those skilled in the art that clear coat films may be available in different colors. The formable metallized laminates described herein may be made in various colors by incorporating appropriately tinted (i.e., colored) clear coat films. As will be known to those skilled in the art, clear coat films may be tinted, for example, using pigments, inks, or mica, and such can be added as desired without undue experimentation. If tinted, clear coats are preferably transparent rather than opaque. Method of Making Film In another aspect, a method of making a chemical resistant clear coat film is provided, wherein the method comprises the following steps: (a) dissolving a polyvinylidene fluoride (PVDF) homopolymer and (meth)acrylic (co)polymer in a solvent system comprising dimethyl sulfoxide and ketone to form a solution, wherein the weight ratio of PVDF homopolymer to (meth)acrylic (co)polymer in the solution is 58:42 or greater; (b) casting the solution onto a base layer; and (c) drying the solution to form the clear coat film. The solution can be made by first dissolving PVDF in DMSO and ketone under heating and agitation. This dissolution step can be done at a temperature sufficient to dissolve the PVDF, such as 30 to 60°C. Once the PVDF is dissolved, (meth)acrylic (co)polymer and other desired optional ingredients, such as crosslinkers or UV absorbers, can be added while maintaining the heating and agitation, until all ingredients are fully dissolved. Alternatively, the solution can be made by first dissolving (meth)acrylic (co)polymer and desired additives, such as UV absorbers, in DMSO and ketone. This dissolution step can be done at a temperature of 30 to 60°C. PVDF can then be dissolved in the DMSO / ketone / acrylic solution under agitation at the same or a slightly higher temperature in the range of, for example, 40 to 65°C, to fully dissolve the PVDF. As will be understood by one of skill in the art, the order of addition of the crosslinker will depend on the type of crosslinker. For example, melamine and blocked isocyanate crosslinkers can be added in any addition sequence even though they are oftentimes added last. If unblocked isocyanate or carbodiimide is used as a crosslinker, it is added just before casting. Once mixed, the clear coat solution of the present disclosure can be cast onto a base layer and then dried by conventional methods. In one embodiment, the base layer can be a carrier, such as a PET film. In certain embodiments, the clear coat solution can be cast directly onto a carrier. In an alternative embodiment, the base layer can be another film that has already been cast on a carrier. This already cast film can comprise one or multiple layers. Such film layers can be, e.g., a clear PVF base film, a metallized film layer, a paint film color base layer or other film layers on which a clear coat is typically applied as a topcoat. U.S. Pat. Nos. 6,287,672, 6,565,955, 6,858,287 and 7,854,985 include examples of the different layers of film that can be disposed under a clear coat film. These previously cast layers may be already fully cured, or partially cured, or they may be uncured. As is known to one of skill in the art, a film layer can be cast wet-on-wet (meaning that the underlying layer is not dry), or wet-on-dry (meaning the underlying layer is dry), depending on the application. In some embodiments, there may be one or more layers between the clear coat layer and the base layer. For example, an adhesive layer may be present between the clear coat layer and the base layer to help the chemical resistant clear coat film adhere to the base layer. It will be appreciated by those of ordinary skill in the art that, as used herein, and unless otherwise noted, the concept of a layer being positioned on another layer, or being “between” two other layers does not necessarily imply that the layers are contiguous (i.e., in intimate contact). Rather, as used herein, the concept of a layer being positioned on another layer or between two other layers is meant to describe the relative positions of the layers within the film or laminate structure. Similarly, as used herein, in a description of a first layer being in contact with a second layer, “opposite” a third layer, the term “opposite” is intended to disclose the relative positions of the first and second layers within the film or laminate structure. As will be known by those skilled in the art, clear coat film may be formed by casting the clear coat solution onto the base layer via knife-over roll coating process, a reverse roll coating process, or a slot die coating process. Slot die coating methods are preferred. These techniques are well known in the art and will not be further discussed herein. Depending on the application, the solution can be cast at a wet thickness of, for example, from 1 to 500 μm. Once it dries, the thickness would be 2.5 – 75 micrometers. As known to one skilled in the art, the casting process can be adjusted to achieve the desired dry film thickness. For example, the dry film thickness may depend on the solids content of the wet solution and the density of solvent. If slot die casting is used, one of skill in the art can vary the pump speed to adjust the volume of solution delivered. The line speed can also be adjusted. If a different casting process is used, the adjustment process in order to achieve the desired dry thickness may be different. The desired thickness will depend on the application. Typically, the clear coat film has a thickness of from 0.1 mil (2.5 micrometers) to 3.0 mils (75 micrometers), and more typically from 0.2 mils (5 micrometers) to 0.6 mils (15 micrometers). The clear coat film of the present disclosure may be coextensive in boundaries with the base layer, or it may be disposed on only a portion or separate portions of the base layer. The clear coat film can be formable from a two-dimensional surface to a three-dimensional surface without objectionable loss of appearance or performance properties. Once the clear coat solution is cast onto the carrier or other film layer(s), the solvent can be optionally flashed off, for example, for 1 to 5 minutes at room temperature, and the film is then dried using any conventional drying technique. For example, the solvents can be evaporated, whereby the clear coat solution becomes drier but still uncured or a fully crosslinked coating film is not formed yet. The clear coat solution can then be cured with the base layer. Curing is preferably carried out thermally at a temperature of 60 to 200°C. The thermally curable solution is preferably one which comprises the crosslinkers described above. Preferably, the dryers are ovens having multiple heating zones wherein each successive heating zone operates at a progressively higher temperature. For example, an oven having four to six heating zones ranging in temperature from 200°F to 400°F may be used. The carrier is stable when exposed to heat while the clear coat film and underlying layers (if present) are dried / cured. The carrier may be removed from the film prior to lamination of the single or multi-layer film onto a substrate. Film Laminate In another aspect of the present disclosure, a film laminate is provided, wherein a film comprising the chemical resistant clear coat film described above is heat pressed onto a substrate to form the film laminate. The clear coat film is the outward facing layer, or topcoat of the laminate. The substrate can comprise polycarbonate, poly(methyl methacrylate) (PMMA), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), cyclic olefin copolymers (COC), polyetherimides (PEI), polystyrenes, polyimides, polypropylenes (PP) and polyethylenes (PE), polyvinyl fluorides (PVF), polyvinylidene fluorides (PVDF), acrylonitrile butadiene styrene copolymer (ABS), or a combination of one or more of the foregoing. In one embodiment, the film can comprise the chemical resistant clear coat film described above as the only layer. In another embodiment, the film can comprise a multi-layer structure as described above, comprising the chemical resistant clear coat film of the present disclosure on one or more film layers. The one or more other film layers can comprise, e.g., a clear PVF base film, acrylic, polyurethane, or polyester resins, a metallized layer, a paint film color base, or other film layers on which a clear coat can be typically applied as a topcoat. U.S. Pat. Nos. 6,287,672, 6,565,955, 6,858,287 and 7,854,985 include examples of the different layers of film that can be disposed under a clear coat film. In such embodiment, the clear coat film is outwardly facing, opposite the substrate, and the one or more other film layers are disposed between the clear coat film and the substrate. In another embodiment, the film laminate may further comprise a release liner releasably adhered to the outwardly facing clear coat film side of the laminate. A release liner is a removable carrier sheet – it can be removed from the clear coat film without damage to the film. The release liner may be of materials known to one skilled in the art. Suitable release liners include polyester films, e.g., polyethylene-terephthalate (PET), or polyolefin films, e.g., polypropylene (PP), or other polymer known films. PET is particularly preferred as a release carrier since PET films are very heat stable and stay flat during film casting and curing even at higher temperatures. An example of a suitable release carrier is REL 8752, which is a silicon-coated release PET film from St. Gobain. The liner can optionally be coated with an adhesive or a low surface energy coating. Suitable low surface energy coatings may include, for example, those formed from polyacrylics, silicones, and / or fluorochemicals. In some embodiments, an additional layer, such as a tacky polyester, may be applied on the chemical resistant clear coat film on the surface opposite the one or more film layers that have already been cast. After further processing, such additional layer may function as a release liner that can later be removed to expose the clear coat film as a topcoat. The chemical resistant clear coat film of the present disclosure can be incorporated into film laminates similar to how conventional clear coats are incorporated into film laminates, provided that the chemical resistant clear coat film is the topcoat of the film laminate. In one embodiment, the film can be a metallized film or formable bright film such as described in U.S. Patent Nos. 6,287,672, 6,565,955 and 6,858,287, incorporated by reference herein, wherein the chemical resistant clear coat film of the present disclosure is the clear topcoat. In another embodiment, a bright metallized formable film laminate can include a formable, weatherable chemical resistant clear coat film as described in the present disclosure, a formable clear coat leveling layer on the weatherable clear coat film, and a discontinuous layer of indium islands deposited on the formable leveling layer, opposite the chemical resistant clear coat film. In another embodiment, a discontinuous layer of metal islands may be deposited upon the formable base layer and then a second discontinuous layer of metal islands can be deposited onto the first discontinuous layer of metal islands. The presence of multiple metallic layers facilitates the retention of optical and reflective properties as the formable laminate is stretched. FIG. 1 is a cross-sectional view of a bright film laminate with a chemical resistant clear coat film in accordance with one aspect of the present disclosure. The chemical resistant clear coat film 10 is the outer, topcoat layer and is opposite to the substrate 14. Leveling layer 11 can comprise PVF, polyurethane or polyester resins. Metal layer 12 is vacuum deposited on the leveling layer 11. Adhesive layer 13 can comprise polyurethane, polyester or acrylic resins. The chemical resistant clear coat film 10, leveling layer 11, metal layer 12, and adhesive layer 13 together form multi-layered film 15. In FIG.1, the multi-layered film 15 has been laminated (e.g., via heat) to a substrate 14 to form bright film laminate 16. Substrate 14 can comprise acrylonitrile butadiene styrene copolymer (ABS), polycarbonate (PC), thermoplastic polyolefin (TPO), polypropylene (PP) or polyethylene terephthalate (PET), etc. In yet another embodiment, the film can be a paint film which itself can comprise one or more layers, such as described in U.S. Patent No.7,854,985, incorporated by reference herein, wherein the chemical resistant clear coat film of the present disclosure is the clear topcoat. Paint film laminates, methods of forming them, and ways of applying them to substrates may be found in U.S. Pat. No.7,854,985. FIG. 2 is a cross-sectional view of a paint film laminate with the chemical resistant clear coat film of the present disclosure. The chemical resistant clear coat film 10 is the outer, topcoat layer. Base coat layer 21 can comprise a PVDF acrylic alloy, polyurethane or polyester or acrylic resins. Optional adhesive layer 22 can comprise polyurethane, polyester or acrylic resins. The chemical resistant clear coat film 10, Base coat layer 21, and optional adhesive layer 22 together form multi-layered film 18. Substrate 14 has been laminated (e.g., via heat) to the multi-layered film 18 to form paint film laminate 17. Substrate 14 can comprise acrylonitrile butadiene styrene copolymer (ABS), polycarbonate (PC), thermoplastic polyolefin (TPO), polypropylene (PP) or polyethylene terephthalate (PET), etc. FIG.3 is a schematic illustration of a generic process for manufacturing a paint film laminate comprising the chemical resistant clear coat film of the present disclosure. As shown, a carrier 33 is advanced from a supply roll 38 through a series of process steps. The carrier 33 preferably comprises an extruded polyester film having a high gloss surface which can impart high gloss to the surface of the clear coat on which other layers, such as base coat or adhesives, are deposited. Advantageously, the carrier 33 comprises polyethylene terephthalate (PET). The carrier 33 can be 2 to 4 mils in thickness, preferably 2 mils in thickness. The carrier 33 passes through a first coating station 40 that may deposit a first coating, such as the chemical resistant clear coat film of the present disclosure. The carrier 33 coated with the first coating then passes through a dryer 41. Next, a second coating is deposited in coating station 42 and dried by dryer 43. The coating stations 40 and 42 may utilize any conventional coating or casting techniques, such as reverse roll coating or slot die coating techniques. Slot die coating methods are preferred. Thereafter, a third coating can be deposited in coating station 44 and dried by dryer 46. A primer coating can then be deposited over the third coating in coating station 48 and optionally dried by dryer 49. Thereafter, an adhesive coating can be deposited in coating station 50 and dried using dryer 51. The primer coating station 48 and adhesive coating station 50 may utilize any conventional coating or casting technique, such as reverse roll coating or slot die coating techniques. The dryers 49 and 51 may utilize any conventional drying technique. A substrate or backing sheet 30 is advanced from a supply roll 52 and laminated to the adhesive-coated surface of the film on carrier 33. The resulting paint film laminate is collected by product roll 54. Dryers 41, 43, 46 and 49 may utilize any conventional drying technique. Preferably, these dryers are ovens having multiple heating zones wherein each successive heating zone operates at a progressively higher temperature. Alternatively, dryer 41 may be eliminated from the process such that the second coating 42, such as base coat or adhesive is applied to the clear coat while the clear coat is still wet using a “wet on wet” coating technique. The carrier 33 can then be removed from the multiple layer film laminate structure, exposing the chemical resistant clear coat topcoat layer before the film laminate is thermoformed and injection molded. The following examples are illustrative of the present invention and are not intended to limit the scope of the invention in any way. Those of skill in the art should, in light of the present disclosure, appreciate that many changes can be made in the specific embodiments that are disclosed and still obtain a like or similar result without departing from the scope of the invention. Examples Materials The following list indicates some of the raw materials and ingredients used in the following examples. Alternative materials or suppliers may be substituted as is appreciated by one skilled in the art. Acrylic Black Dispersion – jet black pigment dispersion custom made for AkzoNobel Acrylic Resin A – 40 wt% solution of OH-functional methacrylic copolymer in solvent mixture of glycol ether acetate and other esters Bayhydur 302 – isocyanate crosslinker available from Covestro BYK-346 – silicone surfactant available from BYK Chemie CYCAT® 600 - strong acid catalyst based on dodecylbenzene sulfonic acid from Allnex Cymel® 303LF – methylated, monomeric melamine crosslinker available from Allnex Cymel® 385 – methylated high imino melamine crosslinker available from Allnex Cymel® XW 3106 - alkylated, high solids melamine crosslinker available from Allnex Desmodur® 2802 – polyfunctional carbodiimide crosslinker available from Covestro Diethylene Glycol Monobutyl Ether Acetate (DB Acetate) are solvents commercially available from Eastman Chemical Dipropylene Glycol Monomethyl Ether (DPM), Methyl Ethyl Ketone (MEK), Dimethyl Phthalate (DMP) – commercially available solvents Dimethylsulfoxide (DMSO) – solvent available from Gaylord Chemical DuPont 68080 – liquid acrylic adhesive for laminating Tedlar® PVF film to substrates, 30 wt% solution of polymethyl methacrylate in solvent (toluene and isopropyl alcohol) mixture available from DuPont Elvacite® 2041 – solid nonreactive acrylic resin based on poly methyl methacrylate (PMMA), manufactured by Mitsubishi Chemical America Elvacite® 2042 – solid nonreactive acrylic resin based on poly ethyl methacrylate (PEMA), manufactured by Mitsubishi Chemical America Elvacite® 4412 - solid OH-functional acrylic resin based on poly methyl methacrylate (PMMA), manufactured by Mitsubishi Chemical America HD-2125 – polycarbonate-based polyurethane dispersion available from Hauthaway Hylar® 5000S – PVDF resin available from Solvay Kynar® 500 – PVDF resin available from Arkema (The Examples below used Kynar® 500 Plus or Kynar® 500 FSF (fluorosurfactant free) grades of PVDF. While some examples refer to the specific grade of Kynar® 500 and others do not, the grade of Kynar® 500 is not expected to make a difference for purposes of this disclosure.) Permuthane® XR-9116 – melamine crosslinker available from Stahl Tinuvin® 900, Tinuvin® 928, Tinuvin® 1130 – UV absorbers of the hydroxyphenyl benzotriazole class, available from BASF Test Methods Films and film laminates prepared as described herein are tested for a number of properties according to the following procedures. Transparency / Haze / Clarity Transmission haze is the percentage of light which passing through deviates from the incident beam greater than 2.5 degree on the average. Total haze value is expressed in percentage, %. The lower the total haze value, the higher the clarity. In general, 0% indicates complete transparency, while greater than 30% is considered to be diffusing or translucent. Total haze is measured by a BYK Hazegard unit in accordance with standard method ASTM D1003. Adhesion Initial cross hatch adhesion test was tested in accordance with ASTM D3359 cross cut tape test method B. This method provides for cutting through the film in a crosshatch pattern of specified spacing, taping the cut area with 3M 989 Scotch tape, and then rapidly removing the tape. The area with cuts is inspected to determine if paint has been loosened or removed, and the area is given a rating. Test results were reported according to the test method from 0B - 5B. 5B is a perfect rating and it means that none of the paint was removed. Heat and Humidity Aging The procedures for testing heat and humidity aging are described in Tables 11 and 12. Heat aging was performed following the GMW16717 method. Heat and humidity aging was performed following the GMW14729 method. Water Bath Water bath testing involved submerging the sample piece in a water bath of 80°C ± 2°C for 3 hours. The requirements for the water bath testing are described in Tables 11 and 12. Color Fastness The conditions and procedures for testing color fastness are described in Tables 11 and 12. In the automotive industry, weathering tests of films and laminates used in automobiles are generally carried out in Florida and Arizona, as color fastness must be guaranteed upon exposure to both high temperatures and sunlight. Such conditions are generally simulated in the laboratory. Color fastness after exposure to light is carefully evaluated by means of various analytical methods which include the exposure of test samples to artificial light sources under controlled irradiation and humidity conditions. Color fastness has a small color change, ΔE measured according to automotive standard SAE J2412 for interior testing (such as for automotive interior trim components) and SAE J2527 for exterior testing. These test standards involve exposing samples to Xenon Arc light, accelerating the simulation of the outdoor or indoor environmental conditions, depending on which test is used. The smaller the ΔE, the better the color fastness. A ΔE of 3 or less is commonly considered acceptable for most automotive applications. Chemical Resistance Various samples of PVDF / acrylic films were tested to evaluate their chemical resistance. The tests included General Motors Worldwide Engineering Standards test procedure GMW14445 (2016), “Sunscreen and Insect Repellant Resistance” and Ford Laboratory Test Method BI 113-08 (2015), “Resistance to Sunscreen Lotion and Insect Repellent, Method A”, chemical resistance testing and physical measurements to determine adequacy of film when exposed to chemicals present in sunscreen lotion and insect repellent. The results for test samples evaluated following the method and procedure specified in the GMW14445 standard were interpreted according to Table 1.

[0002] Table 1 - GMW14445 Test Evaluation and Rating Rating Evaluation 1 No change 2 Slight change of gloss, color, swelling, or any other tolerable effects 3 Significant change of color, swelling, blisters, creases, or other non-tolerable effects 4 Very significant change of color, swelling, blisters, creases, or other non-tolerable effects The results for test samples evaluated following the Ford BI 113-08 standard, Method A were interpreted according to Table 2. Table 2 - Ford BI 113-08 Test Evaluation and Rating Rating Description Allowable Change Discoloration / Spotting None Surface Defect (Step 8) None 1 (No Change) Cloth Impression None Cloth Color Transfer None Discoloration / Spotting AATCC* (Proc. 1) Min.4.5 Surface Defect (Step 8) None 2 (Slight Change) Cloth Impression Very Slight Cloth Color Transfer None Discoloration / Spotting AATCC (Proc.1) Min.4 Sur Slight surface defect - can only be seen at certain 3 (Moderate face Defect (Step 8) angles Change) Cloth Impression No more than 50% of tests area Cloth Color Transfer AATCC (Proc.2) Min.4.5 Discoloration / Spotting AATCC (Proc.1) Min.3.5 4 (Significant Surface Defect (Step 8) Moderate surface defect - can be seen at all Change) angles Cloth Impression Significant cloth impression on more than 50% of tested area Cloth Color Transfer AATCC (Proc.2) Min.4 Discoloration / Spotting AATCC (Proc.1) Rating < 3.5 Surface Defect (Step 8) Severe 5 (Severe Change) Cloth Impression Severe Cloth Color Transfer AATCC (Proc.2) Rating ≤ 3.5 *AATCC refers to the American Association of Textile Chemists and Colorists Examples 1-13: Dissolution of PVDF PVDF powder and solvents were added in different proportions into a 2 oz. glass vial with a magnetic stir bar. Kynar 500 Plus, Kynar 500 FSF and Hylar 5000S were the grades of PVDF used. The vial was placed on a hot plate, and agitation and heating started. The PVDF gradually dissolved with increasing temperature under vigorous agitation. Heating and agitation stopped at 60°C. The solution was allowed to cool down to room temperature and sat overnight. The results are summarized in Tables 3 and 4 (percentages shown are wt%). Table 3 Example Ex.1 Ex.2 Ex.3 Ex.4 Ex.5 Ex.6 Ex.7 Ex.8 Ex.9 Kynar Kynar 500 Plus 500 Hylar PVDF 5000S FSF 12.3% 12.2% 12.3% 11.0% 12.8% 15.1% 11.8% 15.1% 12.4% Dimethyl Sulfoxide 42.2% 35.1% 52.8% 36.9% 36.2% 36.4% 44.1% 50.7% 54.8% (DMSO) Methyl Ethyl Ketone 45.4% 52.6% 35.0% 52.1% 51.1% 48.6% 0.0% 34.2% 32.9% (MEK) 1-Methoxy- 2-Propanol Acetate 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 44.2% 0.0% 0.0% (PMA) Table 4 Example Ex.10 Ex.11 Ex.12 Ex.13 Kynar 500 Plus PVDF 12.9% 13.8% 14.5% 15.2% Dimethyl Sulfoxide 52.2% 51.7% 51.3% 50.6% (DMSO) Methyl Ethyl Ketone 34.9% 34.5% 34.2% 34.3% (MEK) In all the examples, PVDF dissolved to form clear solutions when heated up and remained in solution when cooled down. Ex.7 (comprising no MEK) gelled overnight. All other examples remained in solution after 24 hours under ambient conditions. The results show that one can dissolve PVDF at high concentrations in different solvent systems comprising DMSO and MEK. Examples 14-18: Solution-based PVDF / Acrylic Clear Coat Film The PVDF / acrylic films of Examples 14-18 having the compositions shown in Table 5 were prepared as follows. DMSO and MEK were charged into a lined paint can, and agitation and heating commenced. Kynar 500 was slowly added during the heating and agitation. The agitation speed was increased during the course of addition and dissolution in order to maintain a vortex. After the Kynar 500 fully dissolved, Tinuvin 928, Acrylic Resin A and Permutex 9116 were added in that order. Agitation and heating were maintained until 54°C, to ensure full dissolution of all ingredients. The formulations were filtered through a 100 micron bag and allowed to stand overnight to allow air bubbles to rise. Each formulation was cast on a 2 mil PET release carrier to form a clear coat with a 0.2 -0.5 mil dry film thickness. The coatings were dried at 200°F for 2 minutes, followed by 350°F for 5 minutes in vented static ovens. Table 5 Example Ex.14 Ex.15 Ex.16 Ex.17 Ex.18 PVDF / Acrylic Ratio 30 / 70 40 / 60 50 / 50 58 / 42 68 / 32 Kynar 500 4.6% 6.1% 7.6% 9.1% 10.4% Acrylic Resin A 26.4% 22.8% 19.2% 16.2% 12.4% Tinuvin 928 0.5% 0.5% 0.5% 0.5% 0.5% Permuthane XR-9116 0.7% 0.6% 0.6% 0.5% 0.4% DMSO 33.9% 35.0% 36.0% 36.9% 38.1% MEK 33.9% 34.9% 36.1% 36.9% 38.1% The resulting clear films were subjected to sunscreen lotion and insect repellent testing following GM’s GMW14445 and Ford’s BI 113-08, Method A test methods. The test results are summarized in Table 6. Table 6 Example Ex.14 Ex.15 Ex.16 Ex.17 Ex.18 GMW 14445 4 3 3 2 1 Ford BI 113-08, 1 h test conditions 5 4 3 1 1 Ford BI 113-08, 24 h test 5 3 3 1 1 conditions Examples 19-23: Solution-based PVDF / Acrylic Clear Coat Film The PVDF / acrylic films of Examples 19-23 having the compositions shown in Table 7 were prepared as follows. DMSO and MEK were charged into a lined paint can, and agitation and heating were started. Elvacite 2041 and Tinuvin 928 were slowly added under heating and agitation. When Elvacite 2041 was mostly dissolved at ~40°C, Kynar 500 was slowly added. Dissolution of Kynar 500 at 40°C was fast. Viscosity of the mixture increased rapidly with addition of Kynar 500. Agitation was adjusted to maintain a vortex. The mixture was heated further to 60°C to allow complete dissolution of Elvacite 2041 and Kynar 500. The formulations were filtered through a 100 micron bag and allowed to stand overnight to allow air bubbles to rise. Each formulation was cast on a 2 mil PET release liner to form a clear coat with a 0.2-0.5 mil dry film thickness. The coatings were dried at 200°F for 2 minutes, followed by 350°F for 5 minutes in vented static ovens. Table 7 Example Ex.19 Ex.20 Ex.21 Ex.22 Ex.23 PVDF / Acrylic Ratio 45 / 55 50 / 50 55 / 45 60 / 40 70 / 30 Kynar 500 6.6% 7.4% 8.2% 9.0% 10.4% Elvacite 2041 8.2% 7.4% 6.8% 5.9% 4.5% Tinuvin 928 0.5% 0.5% 0.5% 0.5% 0.5% DMSO 42.3% 42.1% 42.3% 42.2% 42.2% MEK 42.4% 42.6% 42.3% 42.4% 42.4% The resulting clear coat films were subjected to sunscreen lotion and insect repellent testing following GM’s GMW14445 and Ford’s BI 113-08, Method A testing procedures. The test results are summarized in Table 8. Table 8 Example Ex.19 Ex.20 Ex.21 Ex.22 Ex.23 GMW 14445 4 3 3 2 1 Ford BI 113-08, 1 h test conditions 5 4 3 1 1 Ford BI 113-08, 24 h test 5 3 3 1 1 conditions Examples 22 and 23 were deemed acceptable. No change in appearance was observed for Example 23 after the GM and Ford tests. Examples 24 and 25: Weatherability of PVDF / Acrylic Films PVDF / acrylic films having the compositions shown in Table 9 were prepared as follows. DMSO and MEK were charged into a 2.5 gallon stainless steel vessel, and agitation and heating were commenced. Kynar 500 Plus was slowly added under heating and agitation. The agitation speed was increased during the course of addition and dissolution to maintain a vortex. After dissolution of Kynar 500 Plus at around 35-40°C, Tinuvin 928, Acrylic Resin A (for Ex.24) or DuPont 68080 (for Ex.25), and Cymel 303 were added in this order. Agitation and heating were maintained at 50°C to ensure full dissolution of all ingredients. The formulations were filtered through a 100 micron bag and allowed to stand overnight to allow air bubbles to rise. Each formulation was cast as a 0.2-0.5 mil film onto a 0.95 mil Tedlar PVF film (that had already been cast on a PET carrier) on a pilot coater equipped with a slot die coating head and a 3-zone oven. Line speed was maintained at 3 ft / min and the oven temperatures were set at 280°F, 360°F, 385°F, for Zones 1, 2, and 3, respectively. Table 9 Example Ex.24 Ex.25 Kynar 500 Plus 12.3% 10.4% Tinuvin 928 0.6% 0.5% DuPont 68080 0.0% 14.9% Acrylic Resin A 13.5% 0.0% Cymel 303F 0.5% 0.0% DMSO 43.8% 44.5% MEK 29.2% 29.7% The resulting clear coat films were subjected to sunscreen lotion and insect repellent tests following GM’s GMW14445 and Ford’s BI 113-08, Method A testing procedures. Test results and total haze measurements are summarized in Table 10. Test results of an AkzoNobel 0.5 mil Fluorex clear film cast from a 72:28 PVDF homopolymer:acrylic dispersion are included for comparison. The clear coat films of Examples 24 and 25 performed better than the comparative 0.5 mil Fluorex clear film. Table 10 0.5 mil Example Ex.24 Ex.25 Fluorex Clear Film GMW 14445, 80°C, 1 hour 1 1 2 Ford BI 113-08, 74°C, 1 hour 1 1 2 Ford BI 113-08, RT, 24 hours 1 1 1 Total Haze 0.29 0.31 2 The clear coat films of Examples 24 and 25 were then subjected to standard OEM aging and light fastness testing. Both films passed all the tests. The results of the aging and light fastness testing are summarized in Table 11 (clear coat film of Ex. 24 at a thickness of 0.23 mil dry film thickness on a 0.95 mil clear TEDLAR film) and Table 12 (clear coat film of Ex. 25 at a thickness of 0.21 mil dry film thickness of a 0.95 mil clear TEDLAR film). Table 11 Test Procedure Requirements Results No paint particles shall 1 Adhesion: ASTM D3359 cross cut remain on the adhesive Crosscut tape test method B tape after the tape has 5B, no removals been removed No paint particles shall Submerge a sample piece 2 Water Bath in a water bath of 80°C ± remain on the adhesive tape after t Visual No defects 2°C for 3 hours he tape has been removed No change of appearance and haptic Heat Aging GMW16717 method characteristics Visual No defects compared to as- 3 received condition Color DL Da Db DEcmc Change After Heat GMW16717 method DEcmc <= 3.00 -0.49 0.11 1.31 1.77 Aging No blistering; No change of appearance Heat and Humidity GMW14729 method and haptic Visual No defects Aging characteristics compared to as- received condition 4 Color DL Da Db DEcmc Change After Heat and GMW14729 method DEcmc<= 3.00 -0.32 0.09 0.93 1.26 Humidity Aging No blistering; No change of appearance Xenon 1240Kj / m2 Xenon and haptic Interior Test exposure characteristics Visual No defects compared to as- 5 received condition Color DL Da Db DEcmc Change after Xenon SAE J2412 standard DEcmc <= 3.00 -0.04 -0.06 0.27 0.35 Interior Test Xenon No blistering; No 6 Exterior 2500Kj / m2Xenon change of appearance exposure and hapti Visual No defects Test c characteristics compared to as- received condition Color DL Da Db DEcmc Change after Xenon SAE J2527 standard DEcmc<= 3.00 Exterior 0.50 0.11 0.86 1.17 Test Table 12 Test Procedure Requirements Results No paint particles shall Adhesion: ASTM D3359 cross cut remain on the adhesive Crosscut tape test method B tape after the tape has 5B, no removals been removed Submerge a sample piece No paint particles shall Water Bath in a water bath of 80°C ± remain on the adhesive tape afte Visual No defects 2°C for 3 hours r the tape has been removed No change of appearance and haptic Heat Aging GMW16717 method characteristics Visual No defects compared to as- received condition Color DL Da Db DEcmcChange After Heat GMW16717 method DEcmc <= 3.00 -0.31 -0.01 1.09 1.48 Aging No blistering; No Heat and change of appearance Humidity GMW14729 method and haptic charac Visual No defects Aging teristics compared to as- received condition Color DL Da Db DEcmcChange After Heat and GMW14729 method DEcmc <= 3.00 -0.18 0.01 0.67 0.90 Humidity Aging No blistering; No Xenon change of appearance Interior 1240Kj / m2Xenon and haptic Visual No defects Test exposure characteristics compared to as- received condition Color DL Da Db DEcmc Change SAE J2412 standard DEcmc<= 3.00 after Xenon -0.04 -0.10 0.29 0.40 Interior Test No blistering; No Xenon change of appearance Exterior 2500Kj / m2Xenon and haptic exposure charac Visual No defects Test teristics compared to as- 6 received condition Color DL Da Db DEcmcChange after Xenon SAE J2527 standard DEcmc <= 3.00 Exterior 1.27 0.04 1.04 1.41 Test Examples 24 and 25 show that clear coat films prepared in accordance with the present disclosure not only meet the GM and Ford chemical resistance testing, but also continue to meet weatherability requirements. Examples 26 and 27: Laminates Comprising Metallized Films with Chemical Resistant Clear Coats as Topcoat on Tedlar® PVF Base Layer DMSO and MEK were charged into a 2.5 gallon stainless steel vessel, and agitation and heating were commenced. Under heating and adequate agitation, slowly add Hylar 5000S. Increase agitation speed during the course of addition and dissolution to maintain a vortex. After dissolution of Hylar 5000S around 35-40°C, add Tinuvin 928, DuPont 68080 (for Ex.26) or Acrylic Resin A (for Ex.27), and Cymel 303 in order. Keep agitating and heating to 50°C, to ensure full dissolution of all ingredients. Filter the formulations through a 100 micron bag and let them stand overnight to allow air bubbles to rise. Table 13 Example Ex.26 Ex.27 Hylar 5000S 9.9% 11.9% Tinuvin 928 0.5% 0.6% DuPont 68080 14.0% 0.0% Acrylic Resin A 0.0% 12.7% Cymel 303F 0.0% 0.5% DMSO 45.4% 44.6% MEK 30.2% 29.7% Each formulation was cast as a 0.2-0.5 mil topcoat film onto a 0.95 mil Tedlar PVF film on a pilot coater equipped with a slot die coating head and a 3-zone oven. Line speed was maintained at 3 ft / min and the oven temperatures were set at 280°F / 360°F / 385°F for the first, second and third zones, respectively. The resulting film was then metallized with indium and tin on the Tedlar side to an optical density of 1.1- 1.3. The metallized side was then coated with an adhesive coating and laminated to a piece of acrylonitrile butadiene styrene (ABS) or polycarbonate (PC). The clear topcoat side was then subjected to sunscreen lotion and insect repellent testing, following GM’s GMW14445 and Ford’s BI 113-08, Method A testing procedures. Both samples showed good resistance to both GM and Ford testing liquids, with a rating of 1 for all tests. Examples 28-29: Laminates Comprising Metallized Films with Chemical Resistant Clear Coats as Topcoat and Polyurethane Base Layer To make the base coats for Examples 28 and 29, Tinuvin 1130 with DPM were premixed. Then the premix was slowly added into HD-2125 under adequate agitation sufficient to maintain a good vortex. The mixture was left to soak for at least 48 hours prior to use. The Bayhydur 302 was then added under adequate agitation just before casting the coatings. Table 14 Example Ex.28 Ex.29 Chemical Resistant Clear Coat Ex.26 Ex.27 PU Base Layer HD-2125 92.38% 92.38% DPM 5.88% 5.88% Bayhydur 302 0.55% 0.55% Tinuvin 1130 1.18% 1.18% The base coat and the topcoat were then cast in reverse order. First, a layer of wet chemical resistant clear coat solution (using the formulation from Ex.26 or Ex.27, depending on the Example, as indicated in Table 14) was hand cast on a 2 mil PET 8752 release liner from Saint Gobain. The coating was then dried in a vented oven at 250°F for 3 min, followed by 350°F for 3 min, to form a chemical resistant clear coat film having a dry film thickness of 0.2-0.5 mil. A 0.6-0.7 mil dry thickness film of the clear base coat was then cast over the respective clear topcoat specified in Table 14. The coating was then dried in a vented oven at 250°F for 3 min, followed by 350°F for 3 min. The resulting two-layer clear film was then metallized with indium and tin to an optical density of 1.1-1.3 on the base coat side. The resulting metallized side was then coated with an adhesive coating and laminated to pieces of acrylonitrile butadiene styrene (ABS) or polycarbonate (PC). The release liner was then removed and the chemical resistant clear topcoat side was subjected to sunscreen lotion and insect repellent testing, following GM’s GMW14445 and Ford’s BI 113-08, Method A test procedures. The two examples passed all tests with a rating of 1. Examples 30-31: Paint Films with Chemical Resistant Clear Coat as Topcoat and a Color Base Coat Table 15 Example Ex.30 Ex.31 Chemical Resistant Ex.26 Ex.27 Clear Coat Base Coat Kynar 500 22.25% 22.25% Elvacite 2042 7.42% 7.42% Acrylic Black Dispersion 19.91% 19.91% Tinuvin 900 0.74% 0.74% DB Acetate 41.74% 41.74% Dimethyl Phthalate 7.94% 7.94% To make the base color coat, DB acetate and DMP were charged into a container and agitation was started. Tinuvin 900 was added under adequate agitation. Upon complete dissolution of Tinuvin 900, Kynar 500 and Elvacite 2042 were added under vigorous agitation. The temperature of the mixture increased with dispersion of Kynar 500 and dissolution of Elvacite 2042. The temperature was maintained at 127°F until Kynar 500 was completely dispersed. Once dispersion was complete, the acrylic black dispersion was added slowly under agitation. Agitation was continued to ensure adequate mixing. The base coat and the topcoat were then cast in reverse order. First, a layer of wet chemical resistant clear coat solution (using the formulation from Ex.26 or Ex.27, depending on the Example, as indicated in Table 15) was hand cast on a 2 mil PET 8752 release liner from Saint Gobain. The coating was then dried in a vented oven at 250°F for 3 min, followed by 350°F for 3 min, to form a chemical resistant clear coat film having a dry film thickness of 0.2-0.5 mil. Secondly, a 1.5 mil dry thickness film of the color base coat was cast over the respective clear topcoat specified in Table 15. The coating was then dried in a vented oven at 380°F for 4 min. The release liner was then removed, and the chemical resistant clear topcoat side was subjected to sunscreen lotion and insect repellent tests, following GM’s GMW14445 and Ford’s BI 113-08, Method A testing procedures. The two examples passed all tests with a rating of 1. Examples 32-33: Dissolution of PVDF / acrylic in different solvents Kynar 500® FSF® and Elvacite 2041 were dissolved in two different solvent mixtures as follows. The wt.% used and solvents used summarized in Table 16. The solvents were charged into a lined paint container equipped with an air mixer and a digital thermometer. Under agitation and heating, Kynar 500® FSF® was slowly added. The agitation speed was increased during addition and dissolution to maintain a vortex. After the Kynar 500® FSF® fully dissolved / dispersed, Elvacite 2041 was added. The mixture was heated to 60°C and maintained at 60 °C for 15 minutes under agitation, to ensure full dissolution of Kynar 500® FSF® and Elvacite 2041. Table 16 Example Ex.32 Ex.33 Kynar 500® FSF®- PVDF 14.4 % 14.3 % Elvacite 2041 – acrylic resin 6.3 % 6.2 % gamma-Butyrolactone (BLO) - solvent 39.7% 0 Dimethyl Sulfoxide (DMSO) - solvent 0 39.7% Methyl Ethyl Ketone (MEK) - solvent 39.7% 39.8% In both examples, clear solutions of PVDF / acrylic were formed at 60 °C. The solution of Example 32 started gelling upon cooling and was completely gelled when cooled down to 28 °C. The solution of Example 33 remained clear and after 72 hours under ambient conditions all components remained in solution. Examples 34-36: Film with crosslinked clearcoat A clearcoat was prepared as follows. DMSO and MEK were charged into a 2.5 gallon stainless steel vessel, and agitation and heating were commenced. Under heating and adequate agitation, Kynar 500 was slowly added. Agitation speed was increased during the course of addition and dissolution to maintain a vortex. After dissolution of Kynar 500 around 35-40°C, Tinuvin 900, and Elvacite 4412 were added. Agitation and heating to 50°C were kept, to ensure full dissolution of all ingredients. The formulations were then filtered through a 100 micron bag and left standing overnight to allow air bubbles to rise. Melamine crosslinkers (Cymel 303LF and Cymel XW3106) and CYCAT 600 were added into the deairated mix at low agitation for 15 minutes, one hour before the coating operation started. The wt.% of all ingredients used are shown in Table 17. Table 17 Example Ex.34 Kynar 5000 – PVDF 9.0% Elvacite 4412 6.0% Tinuvin 900 0.54% Cymel 303LF – 0.10% melamine crosslinker Cymel XW3106 – 0.40% melamine crosslinker CYCAT 600 – acid 0.10% catalyst DMSO 42.0% MEK 42.0% Two different films comprising a clear coat and a base coat were made: one with the clear coat of Example 34 and one with a commercially available dispersion-based PVDF / nonreactive acrylic clearcoat (Fluorex Clear, ex. AkzoNobel). The clearcoat was cast as a 0.5 mil (DFT) topcoat film onto a 2 mil (50 microns) PET carrier film on a pilot coater equipped with a slot die coating head and a 3-zone oven. Line speed was maintained at 3 ft / min and the oven temperatures were set at 250°F / 320°F / 380°F for the first, second and third zones, respectively. A base coat was coated on top of the clear coat at a dry film thickness of 1 mil and dried in the 3-zone oven wherein the line speed was maintained at 3 ft / min and the oven temperatures were set at 250°F / 320°F / 320°F for the first, second and third zones, respectively. The thus-formed film was then laminated to ABS. The thus-formed laminate was thermofolded to a flat mold at 320 °F before it was cut for making test plaques. The plaques were tested for pencil hardness (according to ISO 15184), scratch resistance (Chrysler Scratch Resistance LP-463DD-18-02 Method A), gloss retention (the percent of 20 ° gloss retained after the samples go through the abrasion resistance test using a BYK Micro Tri-gloss meter), abrasion resistance (Chrysler Crock Mar Resistance LP-463PB-51-01; CS-10; 500 g weight, 1000 cycles), and chemical resistance to brake fluid (exposure to brake fluid for 30 minutes at 158 °F; GMW147014.3.1.3 Method 3). The results are shown in Table 18. Table 18 Example Ex.35 Ex.36 Clearcoat Ex.35 clearcoat Fluorex Clear Test results Pencil hardness 3H HB Scratch resistance 5N* 3N* Gloss retention > 60% < 30% Abrasion resistance pass pass Chemical resistance to brake fluid 9 (pass)** 6 (fail)** * The maximum load that did not result in scratching. ** The rating scale is from 1 (total structure destruction) to 10 (no change at all). Rating 8 (only slight surface change) or above is considered acceptable. The results show that a film with a clear PVDF / acrylic topcoat comprising OH-functional acrylic resin and a crosslinker has improved chemical, scratch, and abrasion resistance (Ex. 35) over a film with a commercially available PVDF / acrylic clearcoat film with nonreactive acrylic resin (Ex.36).

Claims

CLAIMS 1. A chemical resistant clear coat film wherein the film is formed from a solution of polyvinylidene fluoride (PVDF) homopolymer and (meth)acrylic (co)polymer in a solvent system comprising dimethyl sulfoxide and ketone, wherein the weight ratio of PVDF homopolymer to (meth)acrylic (co)polymer in the clear coat film is 58:42 or greater.

2. The clear coat film of claim 1, wherein the film has a total haze value of 1 or less as measured by ASTM D1003, and a chemical resistance rating of 2 or less as measured by GM standard test method GMW14445.

3. The clear coat film of claim 1 or 2, wherein the film has a total haze value of 1 or less as measured by ASTM D1003, and a chemical resistance rating of 2 or less as measured by Ford standard test method BI 113-08.

4. The clear coat film according to any one of the preceding claims, wherein the weight ratio of PVDF homopolymer to (meth)acrylic (co)polymer in the clear coat film is in the range of from 58:42 to 75:

25.

5. The clear coat film according to any one of the preceding claims, wherein the solution further comprises a crosslinker capable of crosslinking the (meth)acrylic (co)polymer.

6. The clear coat film according to claim 5, wherein the (meth)acrylic (co)polymer is an OH- functional (meth)acrylic (co)polymer and the crosslinker is reactive with the OH-functionality of the (meth)acrylic (co)polymer.

7. The clear coat film according to any one of the preceding claims, wherein the ketone is selected from a group consisting of dimethyl ketone (acetone), diethyl ketone, methyl ethyl ketone (MEK), methyl isobutyl ketone, cyclohexanone, substituted cyclohexanone, such as trimethylcyclohexanone (TMCHONE), cyclopentanone, and mixtures thereof.

8. The clear coat film according to any one of the preceding claims, wherein the film further comprises a UV absorber and / or a hindered amine light stabilizer (HALS).

9. A film comprising the chemical resistant clear coat film according to any one of the preceding claims and one or more additional film layers.

10. The film of claim 9, wherein the one or more additional film layers comprise a metallized film layer or a pigmented paint film layer.

11. An article comprising a carrier at least partially coated with the clear coat film according to any one of claims 1 to 8 or with the film of claim 9 or 10.

12. A film laminate comprising: a substrate; and a chemical resistant clear coat film according to any one of claims 1 to 8 or the film of claim 9 or 10, wherein the clear coat film or the film of claim 9 or 10 is coated on at least a portion of the substrate.

13. A method of making a chemical resistant clear coat film according to any one of claims 1 to 8, comprising the following steps: dissolving a polyvinylidene fluoride (PVDF) homopolymer and (meth)acrylic (co)polymer in a solvent system comprising dimethyl sulfoxide and ketone to form a solution, wherein the weight ratio of PVDF homopolymer to (meth)acrylic (co)polymer in the solution is 58:42 or greater; casting the solution onto a base layer; and drying the solution to form the clear coat film.

14. The method of claim 13, wherein the base layer is a carrier, a metallized film layer or a paint film layer.

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