Article comprising Anti-graffiti coating layer

Abstract

An article comprising an anti-graffiti coating layer, a clear layer comprising methyl methacrylate copolymer and a prismatic sheeting layer in this order, wherein the anti-graffiti coating layer is a cured product of a formulation comprising a (meth)acrylate copolymer, and a combination of a radiation-curable difunctional (meth)acrylate monomer with Tg of 100 °C or higher and a radiation-curable difunctional (meth)acrylate monomer with Tg of 75 °C or lower, where Tg refers to the value when the radiation-curable (meth)acrylate difunctional monomer is cured alone.

Description

[0001] PA103288W002

[0002] ARTICLE COMPRISING ANTI-GRAFFITI COATING LAYER

[0003] Background

[0004] Retroreflective materials are configured to receive light rays impinging upon a viewing surface and so alter the rays that they are reflected back toward their sources. Retroreflective material is generally used to enhance low-light visibility of articles to which the retroreflective material is attached. Such material is used in a variety of applications ranging from traffic signs to bicycle reflectors. By enhancing low-light visibility, retroreflective materials enhance safety, provide decoration, and increase conspicuity in general.

[0005] A surface of a retroreflective material can be protected by an overlay film (overlaminate film). By using the overlay film, the colorfastness of digitally printed inks can be enhanced. In addition, the retroreflective material can be protected from damage caused by ultraviolet rays, rainwater, moisture, and the like, and physical damage caused by small stones, sand, and the like, and the adhesion of dirt can be prevented, and improvement of abrasion resistance can also be expected. For the purpose of improving such characteristics, a hard coat layer (for example, see US8,530,054 and US10,072,173) can also be provided on the surface of the overlay film.

[0006] The overlay film generally includes an adhesive layer on one surface of a transparent resin film, and as the transparent resin film, ethylene tetrafluoroethylene (ETFE) having an anti-graffiti function may be used. A resin comprising methyl methacrylate copolymer can also be used as the transparent resin film.

[0007] Summary

[0008] Therefore, an object of the present invention is to provide an article comprising a retroreflective material in which an overlay film in which ETFE is not used is laminated, and an article having excellent graffiti prevention performance and abrasion resistance.

[0009] In one aspect, there is provided an article comprising an anti-graffiti coating layer, a clear layer comprising methyl methacrylate copolymer, and a prismatic sheeting layer in this order, in which the anti-graffiti coating layer is a cured product of a formulation comprising a (meth)acrylate copolymer, and a combination of a radiation-curable difimctional (meth)acrylate monomer with Tg of 100°C or higher and a radiation-curable difunctional (meth)acrylate monomer with Tg of 75°C or lower, where Tg refers to the value when the radiation-curable (meth)acrylate difunctional monomer is cured alone. Here, Tg means the glass transition temperature. This article has an anti -graffiti coating layer as a cured product of a specific component and has a laminated structure as described above, and thus has excellent graffiti prevention performance and abrasion resistance.The (meth)acrylate copolymer can be a radiation-curable (meth)acrylate copolymer. By making the (meth)acrylate copolymer a radiation-curable (meth)acrylate copolymer, abrasion resistance can be remarkably improved while maintaining graffiti prevention performance.

[0010] The formulation further comprises a radiation-curable monofimctional (meth)acrylate monomer with Tg of 40°C or higher, where Tg refers to the value when the radiation-curable monofimctional (meth)acrylate monomer is cured alone. The article with this feature has better suppression of cracks when folding.

[0011] The amount of the radiation-curable monofunctional (meth)acrylate monomer can be from 0.1 to 40% by weight, based on the total weight of the (meth)acrylate copolymer, the radiation-curable difimctional (meth)acrylate monomer with Tg of 100°C or higher, the radiation-curable difimctional (meth)acrylate monomer with Tg of 75 °C or lower, and the radiation-curable monofimctional (meth)acrylate monomer with Tg of 40°C or higher. The article having this feature exhibits properties equal to or better than those of ETFE-based overlay films, especially anti-graffiti performance, excellent scratch resistance, and stay-clean properties. The article with this feature exhibits performance equivalent to or better than those using ETFE overlay film. In particular, the article has excellent anti-graffiti performance, scratch resistance, and stay-clean properties.

[0012] The formulation may not contain a silicone-based (meth)acrylate monomer. By not containing a silicone -based (meth)acrylate monomer, the surface hardness is improved, and both graffiti prevention performance and abrasion resistance are improved.

[0013] The thickness of the anti -graffiti coating layer can be from 2 to 20 micrometers. The article with this feature has particularly excellent anti-graffiti performance, scratch resistance, and flexibility.

[0014] The article can further comprise a colored layer and / or a printed layer on the clear layer side of the prismatic sheeting layer. The article with this feature protects the colored or printed layers from UV rays and scratches.

[0015] The article can further comprise a substrate layer disposed on a side of the prismatic sheeting layer opposite to the clear layer. The article having this configuration can be applied as a traffic sign.

[0016] The article can further comprise a printed logo layer disposed between the anti-graffiti coating layer and the clear layer comprising methyl methacrylate copolymer.

[0017] Brief Description of the Drawings

[0018] The disclosure may be more completely understood in consideration of the following detailed description of various embodiments of the disclosure in connection with the accompanying drawings, in which:FIG. 1 is a schematic cross-sectional view of a first aspect of an article comprising an antigraffiti coating layer;

[0019] FIG. 2 is a schematic cross-sectional view of a second aspect of an article comprising an anti-graffiti coating layer;

[0020] FIG. 3 is a schematic cross-sectional view of a third aspect of an article comprising an anti-graffiti coating layer;

[0021] FIG. 4 is a schematic cross-sectional view of a fourth aspect of an article comprising an anti-graffiti coating layer;

[0022] FIG. 5 is a schematic cross-sectional view of a fifth aspect of an article comprising an antigraffiti coating layer; and

[0023] FIG. 6 is a schematic cross-sectional view of a prismatic sheeting layer.

[0024] Detailed Description

[0025] As used herein, “comprises” and variations thereof do not have a limiting meaning where these terms appear in the description and claims.

[0026] As used herein, “preferred” and “preferably” refer to embodiments of the disclosure that may afford certain benefits, under certain circumstances. However, other embodiments may also be preferred, under the same or other circumstances. Furthermore, the recitation of one or more preferred embodiments does not imply that other embodiments are not useful, and is not intended to exclude other embodiments from the scope of the disclosure.

[0027] As used herein, “a”, “an”, and “the” are not intended to refer to only a singular entity, but rather include the general class of which a specific example may be used for illustration. The terms “a”, “an”, and “the” are used interchangeably with the term “at least one.” The phrases “at least one of’ and “comprises at least one of’ followed by a list refers to any one of the items in the list and any combination of two or more items in the list.

[0028] As used herein, “or” is generally employed in its usual sense comprising “and / or” unless the content clearly dictates otherwise.

[0029] As used herein, all numbers are assumed to be modified by the term “about” and preferably by the term “exactly.” As used herein in connection with a measured quantity, the term “about” refers to that variation in the measured quantity as would be expected by the skilled artisan making the measurement and exercising a level of care commensurate with the objective of the measurement and the precision of the measuring equipment used. Also herein, the recitations of numerical ranges by endpoints include all numbers subsumed within that range as well as the endpoints (e.g., 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4, 5, etc.).

[0030] As used herein, “(meth)acrylic” or “(meth)acrylate” is inclusive of both acrylic and methacrylic (or acrylate and methacrylate).As used herein, “curing” means the hardening or partial hardening of a composition. As used herein, “cured” refers to a material or composition that has been hardened or partially hardened (e.g., polymerized or crosslinked) by curing.

[0031] As used herein, "photopolymerizable composition" means a hardenable composition that can undergo polymerization upon initiation by actinic radiation, such as ultraviolet (UV) radiation.

[0032] Hereinafter, an article comprising an anti-graffiti coating layer according to a suitable embodiment will be described with reference to the drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and the overlapping description will be omitted. In addition, some parts of the drawings are exaggerated for ease of understanding, and the dimensional ratios do not necessarily match those of the description.

[0033] FIG. 1 is a schematic cross-sectional view of a first aspect of an article comprising an antigraffiti coating layer. The article 100 according to the first aspect shown in FIG. 1 comprises an anti -graffiti coating layer 10, a clear layer 11, and a prismatic sheeting layer 20 in this order.

[0034] FIG. 2 is a schematic cross-sectional view of a second aspect of an article comprising an anti -graffiti coating layer. The article 101 according to the second aspect shown in FIG. 2 comprises an anti-graffiti coating layer 10, a clear layer 11, and a prismatic sheeting layer 20 in this order. The article further comprises a first adhesive layer 12 between the clear layer 11 and the prismatic sheeting layer 20.

[0035] FIG. 3 is a schematic cross-sectional view of a third aspect of an article comprising an anti -graffiti coating layer. The article 102 according to the third aspect shown in FIG. 3 has the same configuration as the article according to the second aspect except that the second adhesive layer 30 is provided on the surface of the prismatic sheeting layer 20 opposite to the surface in contact with the first adhesive layer 12.

[0036] FIG. 4 is a schematic cross-sectional view of a fourth aspect of an article comprising an anti -graffiti coating layer. The article 103 according to the fourth aspect shown in FIG. 4 has the same configuration as the article according to the third aspect, except that the article comprises a release liner layer 40 on a surface of the second adhesive layer 30 opposite to the surface in contact with the prismatic sheeting layer 20.

[0037] FIG. 5 is a schematic cross-sectional view of a fifth aspect of an article comprising an antigraffiti coating layer. The article according 104 to the fifth aspect shown in FIG. 5 has the same configuration as the article according to the aspect, except that the substrate layer 50 is provided on a surface of the second adhesive layer 30 opposite to the surface in contact with the prismatic sheeting layer 20.

[0038] Anti-Graffiti Coating LayerThe anti -graffiti coating layer 10 is a cured product of a formulation (hereinafter, this may be referred to as “anti-graffiti coating formulation.”) comprising a (meth)acrylate copolymer, and a combination of a radiation-curable difimctional (meth)acrylate monomer with Tg of 100 °C or higher (hereinafter, this may be referred to as “high Tg difimctional monomer.”) and a radiation-curable difimctional (meth)acrylate monomer with Tg of 75 °C or lower (hereinafter, this may be referred to as “low Tg difimctional monomer.”). Here, Tg refers to the value when the radiation-curable (meth)acrylate difunctional monomer is cured alone.

[0039] Method for Measuring Tg can be as follows: The curable (photopolymerizable) difimctional (meth)acrylate monomer and 1-hydroxy-cyclohexyl -phenyl ketone ("IRGACURE184" available from Ciba) as a photopolymerization initiator is mixed at a mass ratio (monomer compound / photopolymerization initiator) 95 / 5 to prepare a solution. This solution is applied to a glass substrate using a bar coater (# 20) to form a uniform coating film. Next, the coating film is cured by irradiating it with ultraviolet light using a metal halide lamp at an integrated dose of 200mJ / cm2, and a cured product is obtained. The obtained cured product is peeled from the glass substrate to form a measurement sample. Tg of the measurement sample is measured using a thermogravimetric measuring device (so-called "TG-GDA", available for example from Shimadzu Corporation as the DTG-60 Series). The measurement is performed in a nitrogen atmosphere at a rate of temperature increase of 10 °C / minute with a measurement temperature range of -100 - 180 °C.

[0040] The anti -graffiti coating layer 10 does not need to be a layer that can prevent or repel graffiti, but rather it need only be a layer that can enable removal of graffiti with many solvents or solvent-based cleaners without damaging the clear layer 11.

[0041] The (meth)acrylate copolymer contained in the anti-graffiti coating formulation only needs to be a copolymer of a (meth)acrylic acid ester. Preferably, the polymer is a copolymer of methyl methacrylate and a compound having another ethylenically unsaturated bond. As the compound having an ethylenically unsaturated bond other than methyl methacrylate, a monomer (hereinafter, referred to as a “monomer A”) which imparts flexibility to the copolymer and / or a monomer (hereinafter, referred to as a “monomer B”) which increases the Tg of the copolymer can be used.

[0042] Preferably, monomer A has a homopolymer Tg of no greater than about 0° C. Preferably, monomer A is (meth)acrylate monomer and the alkyl group of the (meth)acrylate monomer has an average of about 4 to about 20 carbon atoms. Examples of monomer A comprise 2-methylbutyl acrylate, isooctyl acrylate, lauryl acrylate, 4-methyl-2-pentyl acrylate, isoamyl acrylate, sec-butyl acrylate, n-butyl acrylate, n-hexyl acrylate, 2-ethylhexyl acrylate, n-octyl acrylate, n-decyl acrylate, isodecyl acrylate, isodecyl methacrylate, and isononyl acrylate. The alkyl group can comprise ethers, alkoxy ethers, ethoxylated or propoxylated methoxy (meth)acrylates. Monomer A may comprise benzyl acrylate.Preferably, monomer B has a homopolymer Tg of at least about 10° C., for example, from about 10 to about 50° C. Monomer B may include (meth)acrylic acid, (meth)acrylamide and N-monoalkyl or N-dialkyl derivatives thereof, or a (meth)acrylate. Examples of monomer B include N-hydroxy ethyl acrylamide, diacetone acrylamide, N,N-dimethyl acrylamide, N,N-diethyl acrylamide, N-ethyl-N-aminoethyl acrylamide, N-ethyl-N-hydroxy ethyl acrylamide, N,N-dihydroxyethyl acrylamide, t-butyl acrylamide, N,N-dimethylaminoethyl acrylamide, and N-octyl acrylamide. Other examples of monomer B include itaconic acid, crotonic acid, maleic acid, fumaric acid, 2,2-(diethoxy)ethyl acrylate, 2-hydroxyethyl acrylate or methacrylate, 3-hydroxypropyl acrylate or methacrylate, methyl methacrylate, isobomyl acrylate, 2-(phenoxy)ethyl acrylate or methacrylate, biphenylyl acrylate, t-butylphenyl acrylate, cyclohexyl acrylate, dimethyladamantyl acrylate, 2-naphthyl acrylate, phenyl acrylate, N-vinyl formamide, N-vinyl acetamide, N-vinyl pyrrolidone, and N-vinyl caprolactam.

[0043] As the (meth)acrylate copolymer, functionalized (meth)acrylate copolymer is preferably used alone or in combination with non-functionalized (meth)acrylate copolymer. Functionalized (meth)acrylate copolymer may be obtained from the reaction product of: (a) from 50 to 99 parts by weight of (meth)acrylate ester monomer units (preferably methyl methacrylate) that are homo- or co-polymerizable to a polymer (b) from 1 to 50 parts by weight of monomer units having a pendent, free-radically polymerizable functional group. Examples of such materials are available from Mitsubishi Chemical America (Pasadena, TX) under the trade designations of Elvacite 1010, Elvacite 4026, and Elvacite 4059.

[0044] The high Tg difunctional monomer contained in the anti-graffiti coating formulation only needs to be a cured difunctional monomer having a Tg of 100°C or higher, according to the abovedescribed Tg measuring method. Tg is preferably 100 to 200 °C and is further preferably 100 to 120 °C.

[0045] Examples of the difunctional monomer having a high Tg difunctional monomer include aliphatic urethane dimethacrylate (available from Arkema Inc. under the name of CN 1964CG, Tg = 130°C), tricyclodecanedimethanol diacrylate (available from Arkema Inc. under the name of SR833 S, Tg = 186°C), and ethoxylated (2) bisphenol A dimethacrylate (available from Arkema Inc. under the name of SR348, Tg = 115 °C), tricyclodecane dimethanol dimethacrylate (available from Arkema Inc. under the name of SR834, Tg = 112°C), ethoxylated (4) bisphenol A dimethacrylate (available from Arkema Inc. under the name of SR540, Tg = 108°C), neopentyl glycol diacrylate (available from Arkema Inc. under the name of SR247, Tg = 104°C), dipropylene glycol diacrylate (available from Arkema Inc. under the name of SR508, Tg = 104°C), and diethylene glycol diacrylate (available from Arkema Inc. under the name of SR230, Tg = 100°C). The description of “ethoxylated (2)” means that there are two ethoxy per molecule, and the same applies to other similar notations.The low Tg difunctional monomer contained in the anti-graffiti coating formulation only needs to be a cured difunctional monomer having a Tg of 75°C or lower, according to the abovedescribed Tg measuring method. Tg is preferably -30 to 75 °C and is further preferably 10 to 50 °C.

[0046] Examples of the low Tg difimctional monomer include ethoxylated (3) bisphenol A diacrylate (available from Arkema Inc. under the name of SR349, Tg = 67°C), diethylene glycol dimethacrylate (available from Arkema Inc. under the name of SR231, Tg = 66°C), tripropylene glycol diacrylate (available from Arkema Inc. under the name of SR306 F, Tg = 62°C), aliphatic urethane acrylate oligomer (available from Arkema Inc. under the name of CN2920, Tg = 59°C), aliphatic urethane diacrylate (available from Arkema Inc. under the name of CN9066, Tg = 57°C), 1,4-butanediol dimethacrylate (available from Arkema Inc. under the name of SR214, Tg = 55 °C), ethoxylated (6) bisphenol A dimethacrylate (available from Arkema Inc. under the name of SR541, Tg = 54°C), urethane dimethacrylate (available from Arkema Inc. under the name of CN1970, Tg = 54°C), ethoxylated (2) neopentyl glycol diacrylate (available from Arkema Inc. under the name of SR9209 A, Tg = 48°C), 1,6-hexanediol diacrylate (available from Arkema Inc. under the name of SR238, Tg = 43°C), ethoxylated (4) bisphenol A diacrylate (available from Arkema Inc. under the name of SR601, Tg = 40°C), ethoxylated (8) bisphenol A dimethacrylate (available from Arkema Inc. under the name of SR542, Tg = 35°C), propoxylated (2) neopentyl glycol diacrylate (available from Arkema Inc. under the name of SR9003 B, Tg = 32°C), 1,6-hexanediol dimethacrylate (available from Arkema Inc. under the name of SR239, Tg = 30 °C), tetraethylene glycol diacrylate (available from Arkema Inc. under the name of SR268, Tg = 23 °C), neopentyl glycol dimethacrylate (available from Arkema Inc. under the name of SR248, Tg = 22 °C), cyclohexane dimethanol diacrylate (available from Arkema Inc. under the name of SR406, Tg = 21 °C), alkoxylated hexanediol diacrylate (available from Arkema Inc. under the name of SR564, Tg = 14 °C), propoxylated (2) hexanediol diacrylate (available from Arkema Inc. under the name of SR563, Tg = 14 °C), polyethylene glycol (200) diacrylate (available from Arkema Inc. under the name of SR259, Tg = 13 °C), ethylene glycol dimethacrylate (available from Arkema Inc. under the name of SR206, Tg = 12 °C), ethoxylated (10) bisphenol A diacrylate (available from Arkema Inc. under the name of SR602, Tg = 2 °C), ethoxylated (10) bisphenol dimethacrylate (available from Arkema Inc. under the name of SR602, Tg = -1 °C), triethylene glycol dimethacrylate (available from Arkema Inc. under the name of SR205, Tg = -8 °C), and polyethylene glycol (400) dimethacrylate (available from Arkema Inc. under the name of SR205, Tg = -21 °C).

[0047] The anti-graffiti coating formulation may contain a monofimctional ethylenically unsaturated monomer in addition to the (meth)acrylate copolymer, the high Tg difunctionalmonomer, and the low Tg difunctional monomer. Examples of such a monomer include the above-described monomer A and / or monomer B.

[0048] The anti-graffiti coating formulation may contain a radiation-curable monofunctional (meth)acrylate monomer having a Tg of 40°C or higher. Here, Tg refers to the value when the radiation-curable monofunctional (meth)acrylate monomer is cured alone. The cured condition can be the same as above. The amount of the radiation-curable monofunctional (meth)acrylate monomer is from 0.1 to 40 % by weight, based on the total weight of the (meth)acrylate copolymer, the high Tg difunctional monomer, the low Tg difunctional monomer and the radiation-curable monofunctional (meth)acrylate monomer with Tg of 40 °C or higher. The amount of the radiation curable monofunctional (meth)acrylate monomer may be from 5 to 40 %, or from 10 to 30 %.

[0049] Examples of the radiation-curable monofunctional (meth)acrylate monomer having a Tg of 40°C or higher include isobutyl methacrylate (Tg=53°C), benzyl methacrylate (Tg=54°C), 2-hydroxyethyl methacrylate (Tg=57°C), ethyl methacrylate (Tg=65°C), trimethylsilyl methacrylate (Tg=68°C), 2-hydropropyl methacrylate (Tg=76°C), isopropyl methacrylate (Tg=81°C), cyclohexyl methacrylate (Tg=92°C), isobomyl acrylate (Tg=94°C), acrylic acid (Tg= Tg=105°C), isobomyl methacrylate (Tg=l 10°C), Phenyl methacrylate (Tg=l 10°C), Methyl methacrylate, syndiotactic (Tg=115°C), tert-butyl methacrylate (Tg=118°C), acrylamide (Tg=165°C), potassium acrylate (Tg=194°C), methacrylic acid (Tg=228°C), sodium acrylate (Tg=230°C), and sodium methacrylate (Tg=310°C).

[0050] The anti-graffiti coating formulation can comprise one or more types of menthyl (meth)acrylates as the radiation-curable monofunctional (meth)acrylate monomer having a Tg of 40°C or higher. In some embodiments, menthyl (meth)acrylate is L- menthyl acrylate monomer, or a combination of L- menthyl acrylate monomer and L- menthyl methacrylate monomer.

[0051] Menthyl (meth)acrylate is represented by the formula (1) wherein R1is hydrogen atom or methyl group.

[0052] is represented by the formula (2) wherein R1is as described above.

[0053]

[0054] The content ratio of the components contained in the anti-graffiti coating formulation is optional, but the total of the high Tg difunctional monomer and the low Tg difunctional monomeris preferably 70 to 99 parts by mass, more preferably 75 to 95 parts by mass, and particularly preferably 80 to 90 parts by mass with respect to 100 parts by mass of the (meth)acrylate copolymer.

[0055] In the ratio of the high-Tg difunctional monomer to the low-Tg difunctional monomer, the low-Tg difunctional monomer is preferably 5 to 50 parts by mass, more preferably 15 to 50 parts by mass, and particularly preferably 40 to 50 parts by mass with respect to 100 parts by mass of the high-Tg difunctional monomer.

[0056] Anti-graffiti coating formulation may comprise at least one photoinitiator. Suitable exemplary photoinitiators are those available under the trade designations OMNIRAD from BASF Corporation (Charlotte, USA) and include 1 -hydroxy cyclohexyl phenyl ketone (OMNIRAD 184), 2,2-dimethoxy-l,2-diphenylethan-l-one (OMNIRAD 651), bis(2,4,6 trimethylbenzoyl)phenylphosphineoxide (OMNIRAD 819), l-[4-(2-hydroxyethoxy)phenyl]-2-hydroxy-2-methyl-l -propane- 1 -one (OMNIRAD 2959), 2-benzyl-2-dimethylamino-l-(4-morpholinophenyl)butanone (OMNIRAD 369), 2-Dimethylamino-2-(4-methyl-benzyl)-l-(4-morpholin-4-yl-phenyl)-butan-l-one (OMNIRAD 379), 2-methyl-l-[4-(methylthio)phenyl]-2-morpholinopropan-l-one (OMNIRAD 907), Oligo [2 -hydroxy-2 -methyl- l-[4-(l-methylvinyl)phenyl] propanone] ESACURE ONE (Lamberti S.p.A., Gallarate, Italy), 2-hydroxy-2-methyl-1 -phenyl propan-l-one (DAROCUR 1173), 2, 4, 6-trimethylbenzoyldiphenylphosphine oxide (OMNIRAD TPO), and 2, 4, 6-trimethylbenzoylphenyl phosphinate (OMNIRAD TPO-L). Additional suitable photoinitiators include for example and without limitation, benzyl dimethyl ketal, 2-methyl-2-hydroxypropiophenone, benzoin methyl ether, benzoin isopropyl ether, anisoin methyl ether, aromatic sulfonyl chlorides, photoactive oximes, and combinations thereof.

[0057] In some embodiments, a photoinitiator is present in anti-graffiti coating formulation in an amount of up to about 5% by weight, based on the total weight of polymerizable components in the anti-graffiti coating formulation. In some cases, a photoinitiator is present in an amount of 0.1 wt.% or more, 0.2 wt.% or more, 0.3 wt.% or more, 0.4 wt.% or more, 0.5 wt.% or more, 0.6 wt.% or more, 0.7 wt.% or more, 0.8 wt.% or more, 0.9 wt.% or more, 1.0 wt.% or more, 1.25 wt.% or more, or 1.5 wt.% or more; and 5 wt.% or less, 4.8 wt.% or less, 4.6 wt.% or less, 4.4 wt.% or less, 4.2 wt.% or less, 4.0 wt.% or less, 3.8 wt.% or less, 3.6 wt.% or less, 3.4 wt.% or less, 3.2 wt.% or less, 3.0 wt.% or less, 2.8 wt.% or less, 2.6 wt.% or less, 2.4 wt.% or less, 2.2 wt.% or less, 2.0 wt.% or less, 1.8 wt.% or less, or 1.6 wt.% or less. Stated another way, the photoinitiator may be present in a range of about 0.1-5 wt.%, 0.2-5 wt.%, 0.1 to 2 wt.%, 1.5 to 3 wt.%, or 0.5-5% by weight, based on the total weight of the anti-graffiti coating formulation.

[0058] Further, a thermal initiator can optionally be present in anti -graffiti coating formulation described herein. In some embodiments, a thermal initiator is present in anti-graffiti coating formulation or in an amount of up to about 5% by weight, based on the total weight ofpolymerizable components in the anti-graffiti coating formulation. In some cases, athermal initiator is present in an amount of about 0.1-5% by weight, based on the total weight of polymerizable components in the photopolymerizable composition. Suitable thermal initiators include for instance and without limitation, peroxides such as benzoyl peroxide, dibenzoyl peroxide, dilauryl peroxide, cyclohexane peroxide, methyl ethyl ketone peroxide, hydroperoxides, e.g., tert-butyl hydroperoxide and cumene hydroperoxide, dicyclohexyl peroxydicarbonate, 2,2,-azo-bis(isobutyronitrile), and t-butyl perbenzoate. Examples of commercially available thermal initiators include initiators available from DuPont Specialty Chemical (Wilmington, Del.) under the VAZO trade designation including VAZO 67 (2,2'-azo-bis(2-methybutyronitrile)) VAZO 64 (2,2'-azo-bis(isobutyronitrile)) and VAZO 52 (2,2'-azo-bis(2,2-dimethyvaleronitrile)), and LUCIDOL 70 from Elf Atochem North America, Philadelphia, Pa.

[0059] The anti-graffiti coating formulation may be solvent-free or solvent-based. In a case of containing a solvent, solvents that may be used include, but are not limited to, an ester, an alcohol, a ketone, a carboxylic acid, an aliphatic hydrocarbon, a cyclane, a haloalkane, or an aromatic hydrocarbon, and examples of the solvent include, but are not limited to, one or a plurality of solvents from the group consisting of ethyl acetate, n-butanol, acetone, methyl ethyl ketone, 1-methoxy-2 -propanol, acetic acid, benzene, toluene, ethylbenzene, isopropylbenzene, t-butylbenzene, heptane, cyclohexane, 1 -chlorobutane, 1 -bromobutane, and 1 -iodobutane, and the like.

[0060] In a case where the anti-graffiti coating formulation contains a solvent, the weight ratio of the components other than the solvent is 10 to 95 wt%, 15 to 80 wt%, or 20 to 50 wt% with respect to the entire anti-graffiti coating formulation.

[0061] In order to cure the anti-graffiti coating formulation to form the anti-graffiti coating layer 10, the anti -graffiti coating formulation may be applied onto the clear layer 11, and in a case where the anti-graffiti coating formulation contains a volatile component such as a solvent, at least a part of the volatile component may be volatilized, and then the anti-graffiti coating formulation may be cured by radiation (photopolymerization). The radiation cure may be performed, for example, by passing the film through a UV irradiator (LIGHT HAMMER 6 model I6B with H bulb from Heraeus Noblelight America LLC.) in a nitrogen purge environment with an oxygen concentration of less than 200 ppm and irradiating the film with ultraviolet rays (UV-A) with an intensity of 1680 mW / cm2and a total energy dose of 382 mJ / cm2.

[0062] The thickness of the anti -graffiti coating layer 10 may be from 2 to 20 micrometers, from 5 to 15 micrometers, or from 7 to 12 micrometers. The visible light transmittance of the antigraffiti coating layer 10 can be set to a value of about 70% or more, about 80% or more, or about 90% or more, 100% or less, about 98% or less, or about 95% or less, as an average visible lighttransmitance at a wavelength of 380 nm to 780 nm, in a case of being measured in accordance with JIS A 5759: 2008.

[0063] Clear Layer

[0064] The clear layer 11 is a layer comprising a (meth)acrylate copolymer. The clear layer 11 preferably consists of a copolymer of methyl methacrylate and ethyl acrylate (MMA / EA) or a copolymer of methyl methacrylate and butyl acrylate (MMA / BA). Preferably, the clear layer 11 consists of MMA / EA in which impact modifier particles are dispersed or MMA / BA in which impact modifier particles are dispersed. The impact modifier particles are formed of, for example, a conjugated diene-based rubber, an acrylic rubber, a polyolefin-based rubber, a silicone-based rubber, a fluorine rubber, and the like.

[0065] The thickness of clear layer 11 may be from 25 to 100 micrometers, from 60 to 90 micrometers, or from 70 to 80 micrometers. The visible light transmittance of the clear layer 110 can be set to a value obtained as an average visible light transmitance at a wavelength of 380 nm to 780 nm, which is about 70% or more, about 80% or more, or about 90% or more, 100% or less, about 98% or less, or about 95% or less, in a case of being measured in accordance with JIS A 5759: 2008.

[0066] First adhesive layer

[0067] The articles of the second to fifth aspects include the first adhesive layer 12 between the clear layer 11 and the prismatic sheeting layer 20. The first adhesive layer 12 is typically formed of an optical adhesive (optically clear adhesive).

[0068] Exemplary optical adhesives include pressure -sensitive adhesives (PSAs), heat-sensitive adhesives, solvent-volatile adhesives, and UV-curable adhesives such as UV-curable optical adhesives available from Norland Products, Inc. Exemplary PSAs include those based on natural rubbers, synthetic rubbers, styrene block copolymers, (meth)acrylic block copolymers, polyvinyl ethers, polyolefins, and poly(meth)acrylates. Other exemplary PSAs include (meth)acrylates, rubbers, thermoplastic elastomers, silicones, urethanes, and combinations thereof. In some cases, the PSA is based on a (meth)acrylic PSA or at least one poly(meth)acrylate. Exemplary silicone PSAs include a polymer or gum and an optional tackifying resin. Other exemplary silicone PSAs include a polydiorganosiloxane polyoxamide and an optional tackifier.

[0069] In some cases, the optical adhesive can be a removable adhesive such as those described in, for example, U.S.Pat.Nos. 3,691,140; 4,166,152; 4,968,562; 4,994,322; 5,296,277; 5,362,516, the disclosures of which are incorporated herein in their entireties by reference. The phrase “removable adhesive” for adhering a film to a substrate means an adhesive that affords convenient,manual removal of the film from the substrate without damaging the substrate or exhibiting excessive adhesive transfer from the film to the substrate.

[0070] In some cases, the optical adhesive can be a reusable and / or repositionable adhesive such as those described in, for example, U.S.Pat.No. 6,197,397; U.S. Patent Publication No.

[0071] 2007 / 0000606; and PCT Publication No. WOOO / 56556, the disclosures of which are incorporated herein in their entireties by reference. The phrases “reusable adhesive” or “repositionable adhesive” for adhering a film to a substrate mean an adhesive that (a) affords a temporary, secure attachment of the film to the substrate while affording convenient, manual removal of the film from the substrate without damaging the substrate or exhibiting excessive adhesive transfer from the film to the substrate, and (b) then affords subsequent reuse of the film on, for example, another substrate.

[0072] Prismatic Sheeting Layer

[0073] With reference to FIG. 6, an exemplary prismatic sheeting layer 20 comprises at least a multitude of cube-comer elements 14 and a body layer 18. The body layer 18 may also be referred to as an overlay film as well as a base substrate. The body layer 18 typically has a thickness of at least 20 micrometers and more typically at least 50 micrometers. The body layer 18 usually has a thickness less than 1,000 micrometers, and typically no greater than 250 micrometers. The cubecomer elements 14 project from a first, typically rear side of the body layer 18. The cube-comer elements 14 and the body layer 18 are typically formed from a light-transmissive polymeric material. A typical visible light transmittance of the light-transmissive polymeric material is a value obtained as an average visible light transmittance at a wavelength of 380 nm to 780 nm, which is measured in accordance with JIS A 5759:2008, and is about 70% or more, about 80% or more, or about 90% or more, 100% or less, about 98% or less, or about 95% or less.

[0074] In a preferred embodiment, the body layer 18 is the outermost layer on the front side of the prismatic sheeting layer 20. As shown in FIG. 6, light enters the prismatic sheeting layer 20 through the front surface 21. The light then passes through the body layer 18 and strikes the planar faces of the cube-comer elements 14 and returns in the direction from which it came as shown by arrow 23. The body layer 18 functions to protect the sheeting from outdoor environmental elements and / or provides mechanical integrity to the sheeting.

[0075] The prismatic sheeting layer 20 may comprise a land layer such as shown in U.S. Patent No. 5,450,235. In some embodiments, the land layer is integral with the cube- comer elements meaning that the land and cubes are formed from a single polymeric material — not two different polymeric layers subsequently united together. Particularly for embodiments, wherein the retroreflective sheeting is flexible, the land layer 16, typically, has a thickness in the range of about 0 to 150 micrometers, and preferably in the range of approximately 1 to 100 micrometers. Thethickness of the land is preferably no greater than 10 percent of the height of the cube comer elements, and more preferably about 1 to 5 percent thereof

[0076] Although the embodiment of the invention shown in FIG. 6 has a single body layer 18, it is within the scope of the present invention to provide more than one body layer 18 (e.g. a multilayer body). A seal fdm 30 is bonded to the (e.g. cube-comer) structured surface. The seal film 30 typically functions to maintain an air interface with the (e.g. backside) of the cube-comer elements to enhance retroreflectivity.

[0077] The prismatic sheeting layer 20 may comprise a seal film 30 as shown in FIG. 6. The seal film 30 is usually made of a polymer material and may be a colored film (colored layer) or a printed film (printed layer). The colored film is preferably a plastic film comprising a plastic resin such as polyester, which contains a suitable amount of one or more pigments such as titanium oxide, silica, red oxide, and the like, to impart a desired color. Illustrative examples of colors include white, gray, red, yellow, green, orange, blue, and brown. Colorants such as dyes and pigments may be used to impart a desired color to the colored film as appropriate for the intended application. Those skilled in the art will be able to readily select suitable colorants and colorant loadings for intended applications. The printed film is a film on which various printing is performed on a plastic resin such as polyester, and the reflectivity can be increased by incorporating a reflective material (e.g., aluminum flake powder, pearlescent pigment, etc.) into the printing.

[0078] Second Adhesive Layer

[0079] The second adhesive layer 30 is formed on a surface of the prismatic sheeting layer 20 opposite to the surface in contact with the first adhesive layer 12. The second adhesive layer 30 may be a pressure-sensitive adhesive (PSA), a structural adhesive, a hot melt adhesive, a radiation-curable adhesive, or the like, in which various adhesives such as acrylic, urethane, and epoxy are used as components. The second adhesive layer 30 is preferably formed of a PSA, and may be the same as the first adhesive layer.

[0080] Release Liner Layer

[0081] The fourth aspect of an article comprising an anti-graffiti coating layer comprises a release liner layer 40 on a surface of the second adhesive layer 30 opposite to a surface in contact with the prismatic sheeting layer 20 as shown in FIG. 4. The release liner layer 40 is formed of a release liner. Release liners generally have a low adhesion surface for contacting the adhesive layer. The release liner can include paper such as kraft paper, or polymer films such as poly (vinyl chloride), polyester, polyolefin, cellulose acetate, ethylene vinyl acetate, polyurethane. The release liner can be coated with a layer of release agent such as a silicone -containing material or a fluorocarbon-containing material. The release liner can include a polymer film coated with paper or polyethylene coated with a silicone-containing material. Exemplary release liners include CP Films Inc. under the trade names “T-30” and “T-10”, which have a silicone release coating on a polyethylene terephthalate film.

[0082] Substrate Layer

[0083] The substrate layer 50 is a material to which the laminate of the anti -graffiti coating layer 10, the clear layer 11, the first adhesive layer 12, the prismatic sheeting layer 20, and the second adhesive layer 30 is fixed, and in the case of traffic sign applications, the substrate layer 50 can be a metal plate, a resin plate, a wood plate, a glass plate, a concrete panel, or the like to which a traffic sign is attached.

[0084] The first aspect of an article can be obtained, for example, by curing an anti-graffiti coating formulation on the clear layer 11 to form an anti-graffiti coating layer 10 and physically fixing the anti -graffiti coating layer 10 on the prismatic sheeting layer 20. The second aspect of an article can be obtained, for example, by forming the first adhesive layer 12 on the surface of the clear layer 11 of the laminate of the anti -graffiti coating layer 10 and the clear layer 11 obtained as described above, where the clear layer 11 is not formed with the anti -graffiti coating layer 10, and joining the prismatic sheeting layer 20 to the laminate. For example, the article of the third aspect can be formed by bonding the laminate of the anti -graffiti coating layer 10, the clear layer 11, and the first adhesive layer 12 obtained in the same manner as the second aspect of an article to the surface of the prismatic sheeting layer 20 in which the second adhesive layer 30 is formed on one side, on the side opposite to the second adhesive layer 30 side. The fourth aspect of an article can be obtained, for example, by laminating the release liner layer 40 on the third aspect of an article obtained as described above, and the fifth aspect of an article can be obtained, for example, by bonding the third aspect of an article obtained as described above to the substrate layer 50.

[0085] Printed Logo Layer

[0086] The article can further comprise a printed logo layer disposed between the anti-graffiti coating layer and the clear layer comprising methyl methacrylate copolymer. The printed logo layer can be created by printing a logo onto the clear layer before applying the anti-graffiti layer. The presence of a printed logo layer makes it easy to identify whether a sign has an anti-graffiti overlaminate. It could also contain information such as a lot code, product name, manufacturer name, or date of manufacture.Examples

[0087] Unless otherwise noted, all parts, percentages, ratios, etc. in the Examples Section and the rest of the specification are by weight. If not specified below, reagents are available from fine chemical vendors or may be synthesized by known methods.

[0088] The following abbreviations are used in the Example Section: g = gram, mg = milligram, kg = kilogram, mL = milliliter, mm = millimeter, nm = nanometer, °C = degrees Celsius, °F = degrees Fahrenheit, min = minute, Tg = glass transition temperature, Pa = pascal, and wt% = weight percent.

[0089] Materials Used in the Examples

[0090]

[0091] Preparation of anti-graffiti coating formulation (coating solution)

[0092] Coating solution (CS-1)

[0093] 17.10 grams ofB44, 113.00 grams of SR238, 89.40 grams of MEK, 129.30 grams of MP-OH were added into a brown glass jar. Then 3.80 grams of Tinuvin 477 and 3.80 grams of Tinuvin 479 were added as an ultraviolet absorber, 1.25 grams of Tinuvin 123 was added as a HALS, 1.28 grams of OR184 and 1.28 grams of OR819 were added as a photo initiator, 0.16 grams of Tegorad 2250 was added as a leveling agent. The jar was closed with a polypropylene lid and the mixture was mixed at ambient temperature and pressure until the mixture was clear and the viscosity of the entire mixture was uniform. CS-1 was provided as a coating solution for Comparative example 3 (CE-3).

[0094] Coating solution (CS-2 to CS-8)

[0095] Coating solutions CS-2 to CS-8 were also prepared using the same procedure as CS-1. The charged amounts on composition are listed in Table 1.

[0096] Table 1. Compositions of coating solution (CS-1 to CS-8)

[0097] < < < < < <

[0098]

[0099] Preparation of anti -graffiti coating layer on 1170c substrate

[0100] The preparation procedures of CE-1 to CE-4 and EX-1 to EX-6 are described below. Each product obtained from the preparation procedures is referred to as 'overlaminate'

[0101] Overlaminates for Comparative Examples (CE-1 to CE-4)

[0102] 3M™ Premium Protective Overlay Film Series 1160i having an ETFE (Ethylene tetrafluoroethylene) surface (structure of 1160i : ETFE layer / Pressure Sensitive Adhesive Layer / Release Liner Layer) was used as comparative example 1 without anti-graffiti coating layer (CE-1).

[0103] 3M™ ElectroCut™ Film 1170c Clear having a PMMA base surface (structure of 1170c: Clear layer comprising methyl methacrylate copolymer / Pressure Sensitive Adhesive Layer / Release Liner Layer) was used as comparative example 2 (CE-2).

[0104] CE-3 and CE-4 were prepared using the 1170c substrate and CS-1 and CS-2 coating solutions, respectively. (The coating solution CS-1 was applied to 1170c, the resulting coating surface after drying had low gloss and CE-3 could not be obtained.) The coating solutions were applied to the substrate using a die coating method with an 8mil coating gap. After drying at 206 °F in air. The coated substrate was passed into UV irradiator (H-bulb of Fusion UV System Inc. DRS model) in a nitrogen purge environment with an oxygen concentration below 200 parts per million (ppm). During irradiation, ultraviolet rays (UV-A) with an intensity of 1680 mW / cm2were irradiated on the coated surface until a total energy dose of 382 mJ / cm2was reached. The anti -graffiti coating layer with a thickness of 10 micrometers on the 1170c substrate was prepared as CE-3 and CE-4, respectively.

[0105] Overlaminates for Examples (EX-1 to EX-6)

[0106] EX-1 to EX-6 were prepared using 1170c substrate and CS-3 to CS-8 coating solutions, respectively. The anti -graffiti coating layer with a thickness of 10 micrometers on the substrate as EX-1 to EX-6 was prepared using the same procedure of the CE-3 and CE-4, respectively.

[0107] Examples and Comparative Examples

[0108] Test methods:

[0109] Method for determining anti-graffiti performance (TM-1)

[0110] The anti-graffiti performance was assessed using the following procedure.

[0111] 1. Circles that were approximately 2 ! ” in diameter were marked on sheets of 3M™ Diamond Grade™ DG3Reflective Sheeting 4090 (structure: Prismatic Sheeting Layer Pressure Sensitive Adhesive Layer / Release Liner Layer) using a sharpie marker to mark where the retroreflectivitywould be measured. This was done because retroreflective sheeting brightness varies from spot to spot and it was important to measure the retroreflectivity of the same spot initially (of the base sheeting) and again after application of the overlaminate (to determine the impact of the overlaminate on the retroreflectivity), and again after graffiti was applied and cleaned (to determine if the retroreflectivity was adversely affected by the cleaning process).

[0112] 2. The retroreflectivity was measured using a handheld RetroSign GR3 retroreflectometer. The retroreflectivity was measured using a geometry of 0 deg sheeting orientation, -4 deg entrance angle, and 0.2 deg observation angle. The retroreflectity of each circle area to be tested was recorded.

[0113] 3. Articles comprising anti-graffiti coating layer of Example and Comparative Examples were obtained by laminating the overlaminate (either for Comparative Examples or for Examples) on 3M™ Diamond Grade™ DG3Reflective Sheeting 4090 at room temperature using a ROLLSROLLER Flatbed Applicator®. Care was taken to avoid air bubbles, wrinkles, etc. and if such defects occurred, the circle was not used.

[0114] 4. After application of the overlaminate, the retroreflectivity was remeasured using the same device and geometry as above and the retroreflectivity retention (retro after overlaminate was applied divided by retro before overlaminate was applied) was determined.

[0115] 5. Graffiti was applied using commercially available spray paints. Paints included Rustoleum Gloss Protective Enamel 7768830 Gloss Burgandy (an oil-based spray paint available from Rustoleum Corporation) and Cobalt Blue Liquitex Spray paint (a water-based spray paint available from Liquitex). The paints were applied by spraying in a spray booth with the samples with a distance of about 1 foot from the overlaminate. The circles were covered with paint and allowed to air dry. The articles were then placed in a 150 °F oven and further dried for at least one day. The oven drying was intended to simulate drying in the sun. Graffiti can be more difficult to remove after long periods of time or when exposed to high temperatures in warm climates.

[0116] 6. The graffiti was removed with solvents and / or commercially available cleaners by applying the cleaner onto the graffiti and being removed with a cloth rag or paper towel. In some cases, a plastic razor blade was used.

[0117] 7. After cleaning, any residual graffiti was removed with additional cleaning.

[0118] 8. The ease of removal or time to remove the graffiti was assessed in some cases.

[0119] 9. The retroreflectivity was measured of each circle using the same device and geometry as above). The retroreflectivity retention after cleaning the graffiti was determined by calculating the ratio of the reflectivity after cleaning to the retroreflectivity of the sheeting with the overlaminate (not the base sheeting before the overlaminate was applied).Method for determining steel wool abrasion resistance (TM-2)

[0120] The steelwool abrasion resistance was evaluated using the following procedure. First, the overlaminate was laminated on the prismatic sheet and the overlaminate was laminated on the aluminum plate using the same procedure as in TM-1. The Examples and Comparative Examples was evaluated by the surface changes after the steel wool abrasion test using 3 cm diameter circular head with #0000 steel wool after 10 cycles at 1 kg load and at 60 cycles / min. rate. The strokes were 85 mm long. The instrument used for the test was an abrasion tester (obtained under the trade designation “5800 HEAVY DUTY LINEAR ABRASER” from TABER INDUSTRIES). After the steel wool abrasion resistance test was completed, the overlaminate was observed for the presence of scratches and the retroreflectivity was measured before and after the steelwool abrasion resistance test and the retro retention % was calculated.

[0121] Method for stay clean and easy clean performance using dirt pick up resistance test (TM-3)

[0122] Stay clean and easy clean performance were evaluated by a dirt pick up resistance test using the following procedure. First, the overlaminate was laminated on the prismatic sheet and the overlaminate was laminated on the aluminum plate using the same procedure as in TM- 1. The aluminum plate with the overlaminate placed on the side wall of the metal paint can with PVC tape. 49.5 g of sand (EMD Milipore Co. SX0070 CAS# 14808-60-7), 0.1 ml brake fluid and 0.5 g contaminant (SDL ATLAS synthetic soil from SDL ATLAS) were added into the paint can. The paint can was tumbled with 80 rpm for 24 hours. The plate was removed and then the retroreflectivity was measured and retro retention % was calculated as a stay clean performance. The surface of the tested overlaminate was wiped 3 times by water-soaked cotton and then the retroreflectivity was measured and retro retention % was calculated as the easy clean performance.

[0123] Results

[0124] The resulting CE-1, CE-2, CE-4 and EX-1 to EX-6 articles were tested using methods described above. The coating solution CS-1 was applied to 1170c, the resulting coating surface after drying had low gloss and various tests could not be performed (CE-3). Table 2 summarizes Evaluation results of prismatic film with protective coating layer with retroreflectivity [cd / lx / m2] and retro retention percentage.

[0125] Anti-Graffiti Performance

[0126] In the evaluation of anti -graffiti performance, the ETFE 1160i of CE-1 demonstrated a Retro retention percentage of over 90% after testing. In contrast, the PMMA base 1170c of CE-2 exhibited significantly lower Retro retention percentages of 50.1%, 36.9%, and 39.8%, all well below 80%. CE-4, which is a UV-curable topcoat within the compositional range described inUS10072173B2, also showed Retro retention percentages below 80%, specifically 22.7%, 7.6%, and 76.0%. These results indicate that CE-2 and CE-4 do not possess superior anti-graffiti performance. Conversely, the protective coatings of the present invention, EX-1 through EX-6, all demonstrated higher Retro retention percentages compared to CE-2. Notably, EX-1 and EX-3 exhibited Retro retention percentages comparable to or exceeding that of the ETFE film 1160i (CE-1).

[0127] Steel Wool Abrasion Resistance

[0128] Following the steel wool abrasion resistance test, the invented coatings EX-1 through EX- 4 showed significantly higher Retro retention percentages compared to CE-1 and CE-2. While no visible scratches were observed on the surfaces of EX-1 through EX -4, numerous scratches were evident on the surfaces of CE-1 and CE-2.

[0129] Stay Clean Performance

[0130] In this test, all comparative examples and experimental examples, except for CE-1, demonstrated Retro retention percentages in the range of 30-50%. In contrast, the ETFE film of CE-1 exhibited a low value of 13.0%. These results suggest that the invented coatings possess superior stay clean performance compared to the ETFE film of CE-1.

[0131] Easy Clean Performance

[0132] In the easy clean performance test, EX-1 through EX-4 exhibited Retro retention percentages of over 90%, surpassing those of CE-1 and CE-2. Additionally, small scratches were observed on the surfaces of CE-1 and CE-2 after the test.

[0133] From these results, it could be concluded that the invented anti-graffiti coating provides equal or higher anti-graffiti performance, scratch resistance, stay and easy clean-ability than ETFE and PMMA base overlaminate films.

[0134] Table 2 Evaluation results of prismatic film with protective coating layer with retroreflectivity [cd / lx / m2] and retro retention percentage.

[0135]

[0136]

[0137]

Claims

What is claimed is:

1. An article comprising an anti-graffiti coating layer, a clear layer comprising methyl methacrylate copolymer and a prismatic sheeting layer in this order,wherein the anti-graffiti coating layer is a cured product of a formulation comprising a (meth)acrylate copolymer, and a combination of a radiation-curable difimctional (meth)acrylate monomer with Tg of 100 °C or higher and a radiation-curable difimctional (meth)acrylate monomer with Tg of 75 °C or lower, where Tg refers to the value when the radiation-curable (meth)acrylate difimctional monomer is cured alone.

2. The article according to claim 1,wherein the (meth)acrylate copolymer is a radiation-curable (meth)acrylate copolymer.

3. The article according to claim 1,wherein the formulation further comprises a radiation-curable monofimctional (meth)acrylate monomer with Tg of 40 °C or higher, where Tg refers to the value when the radiation-curable monofimctional (meth)acrylate monomer is cured alone.

4. The article according to claim 3,wherein the amount of the radiation-curable monofimctional (meth)acrylate monomer is from 0.1 to 40 % by weight, based on the total weight of the (meth)acrylate copolymer, the radiation-curable difimctional (meth)acrylate monomer with Tg of 100 °C or higher, the radiation-curable difimctional (meth)acrylate monomer with Tg of 75 °C or lower and the radiation-curable monofimctional (meth)acrylate monomer with Tg of 40 °C or higher.

5. The article according to claim 1,wherein the formulation comprises no silicone -based (meth)acrylate monomer.

6. The article according to claim 1,wherein the thickness of the anti -graffiti coating layer is from 2 to 20 micrometers.

7. The article according to claim 1,wherein the article further comprises a colored layer and / or a printed layer disposed on the clear layer side of the prismatic sheeting layer..

8. The article according to claim 1,wherein the article further comprises a substrate layer disposed on the side of the prismatic sheeting layer opposite to the clear layer.

9. The article according to claim 1,wherein the article further comprises a printed logo layer disposed between the anti-graffiti coating layer and the clear layer comprising methyl methacrylate copolymer.

Images