Digitally embossed floor coverings and methods of preparing the same

Abstract

Digitally embossed floor coverings (200) are provided comprising: a substrate (202) comprising polyvinylchloride, polyurethane, acrylic, melamine, and / or polyolefin; a decorative layer (203) applied to the substrate (202); a wear layer (201) applied to the decorative layer (203), and an additional layer (204) on top of the wear layer (201). A texture is digitally embossed into the wear layer (201) prior to application of the additional layer (204). The wear layer (201) is prepared from a UV radiation-curable coating composition comprising: a reactive diluent (1) comprising 2 to 6 acrylate functional groups, present in the curable coating composition in an amount of 10 to 40 percent by weight; and a free radical-polymerizable compound, present in the curable coating composition in an amount of 30 to 80 percent by weight. The free radical-polymerizable compound comprises 2 to 6 acrylate functional groups and an aliphaticpolyester- or polyurethane-functional linking group. Also provided are methods of preparing the floor coverings (200).

Description

DIGITALLY EMBOSSED FLOOR COVERINGS AND METHODS OF PREPARING THE SAMEFIELD OF THE DISCLOSURE

[0001] The present disclosure relates to multi-layer, digitally embossed floor coverings and methods of preparing them.BACKGROUND OF THE DISCLOSURE

[0002] Conventional floor coverings are typically multi-layer composites that include one or more wear layers combined with a substrate and resin to form a flooring sheet, plank or tile. The substrate usually comprises a continuous polymeric material, or a felted or matted fibrous material of overlapping, intertwined filaments or fibers. A wear layer may be defined as any layer that improves the wear properties of the floor covering, such as improved gouge and tear resistance, improved stain resistance, or improved scratch and abrasion resistance, compared to the same floor covering without such a wear layer.

[0003] Wear layers are often formed from plastisols; i. e., colloidal dispersions of polymeric particles, usually polyvinyl chloride (PVC), in a liquid plasticizer. When heated to around 180°C (356°F), the plastic particles absorb the plasticizer, causing them to swell and fuse together, forming a viscous gel. Once this is cooled to below 60°C (140°F) it becomes a flexible, permanently plasticized solid product. This solid plastisol may be mechanically embossed or treated with a blowing or foaming inhibitor for chemically embossing the surface. However, processing times for plastisol wear layers can be long; the processing times and high processing temperatures needed to form plastisol wear layers are a manufacturing disadvantage.

[0004] It would be desirable to provide an embossed floor covering that demonstrates abrasion and cracking resistance as expected in the industry while allowing for digital embossing.SUMMARY OF THE DISCLOSURE

[0005] Digitally embossed floor coverings are provided comprising: (a) a substrate comprising polyvinylchloride, polyurethane, acrylic, melamine, and / or polyolefin; (b) adecorative layer applied to the substrate; (c) a wear layer applied to the decorative layer, and (d) an additional layer on top of the wear layer (c). A texture is digitally embossed into the wear layer prior to application of the additional layer.

[0006] The wear layer is prepared from a UV radiation-curable coating composition comprising: (1 ) a reactive diluent comprising 2 to 6, or 2 to 4, or 2 to 3 (meth)acrylate functional groups, present in the curable coating composition in an amount of at least 10 percent by weight, or at least 15 percent by weight, or at least 20 percent by weight, and most 40 percent by weight, or at most 30 percent by weight, or at most 25 percent by weight, based on the total weight of the curable coating composition; and (2) a free radical-polymerizable compound different from the reactive diluent (1 ), present in the curable coating composition in an amount of at least 30 percent by weight, or at least 40 percent by weight, or at least 60 percent by weight, and at most 80 percent by weight, or at most 70 percent by weight, or at most 65 percent by weight, based on the total weight of the curable coating composition. The free radical-polymerizable compound comprises: (i) 2 to 6, or 2 to 4, or 2 to 3 (meth)acrylate functional groups; and (ii) a polyester- or polyurethane-functional linking group, wherein the group (ii) is aliphatic.

[0007] Also provided are methods of preparing floor coverings, comprising:(a) applying a decorative layer to a flooring substrate, wherein the flooring substrate comprises polyvinylchloride, polyurethane, acrylic, melamine, and / or polyolefin;(b) applying a wear layer to the decorative layer, wherein the wear layer is prepared from a UV radiation-curable coating composition comprising:(1 ) a reactive diluent comprising 2 to 6, or 2 to 4, or 2 to 3 (meth)acrylate functional groups, present in the curable coating composition in an amount of at least 10 percent by weight, or at least 15 percent by weight, or at least 20 percent by weight, and at most 40 percent by weight, or at most 30 percent by weight, or at most 25 percent by weight, based on the total weight of the curable coating composition; and(2) a free radical-polymerizable compound different from the reactive diluent (1 ), present in the curable coating composition in an amount of at least 30 percent by weight, or at least 40 percent by weight, or at least 60 percent by weight, and at most 80 percent by weight, or at most 70 percent by weight, or at most 65 percent by weight,based on the total weight of the curable coating composition; wherein the free radical- polymerizable compound comprises:(i) 2 to 6, or 2 to 4, or 2 to 3 (meth)acrylate functional groups; and(II) a polyester- or polyurethane-functional linking group; wherein the group (ii) is aliphatic;(c) applying an inhibitor solution via digital printing in a pattern on top of the wear layer;(d) partially curing the UV radiation-curable coating composition;(e) removing the inhibitor layer and the UV radiation-curable coating composition that remains uncured, to form an embossed pattern in the wear layer; and(f) applying an additional layer on top of the wear layer; and(g) conducting a final curing step to cure all layers and form an embossed floor covering.BRIEF DESCRIPTION OF THE DRAWINGS

[0008] FIG. 1 illustrates a schematic cross-sectional view of an example of a digitally embossed floor covering in accordance with the present disclosure.

[0009] FIG. 2 illustrates a schematic cross-sectional view of an example of a floor covering in accordance with the present disclosure, but no indentations from a digitally embossed pattern are shown. Primer layers between the flooring substrate and the decorative layer and between the wear layer and additional layer are shown.

[0010] FIG. 3 illustrates a schematic cross-sectional view of an example of a digitally embossed floor covering in accordance with the present disclosure. The wear layer comprises a preliminary layer applied to the decorative layer, and a second layer prepared from a UV radiation-curable coating composition and applied to the preliminary layer. Indentations from a digitally embossed pattern penetrate through the second layer to expose portions of the preliminary layer.

[0011] Note that the relative thicknesses of each layer shown in the Figures are not representative of actual relative thicknesses.DETAILED DESCRIPTION OF THE DISCLOSURE

[0012] Other than in any operating examples, or where otherwise indicated, all numbers expressing quantities of ingredients, reaction conditions and so forth used in the specification and claims are to be understood as being modified in all instances by the term “about.” Accordingly, unless indicated to the contrary, the numerical parameters set forth in the following specification and attached claims are approximations that may vary depending upon the desired properties to be obtained by the present disclosure. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.

[0013] Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the disclosure are approximations, the numerical values set forth in the specific examples are reported as precisely as possible. Any numerical value, however, inherently contain certain errors necessarily resulting from the standard deviation found in their respective testing measurements.

[0014] Also, it should be understood that any numerical range recited herein is intended to include all sub-ranges subsumed therein. 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.

[0015] As used in this specification and the appended claims, the articles "a," "an," and "the" include plural referents unless expressly and unequivocally limited to one referent.

[0016] The various embodiments and examples of the present disclosure as presented herein are each understood to be non-limiting with respect to the scope of the disclosure.

[0017] As used in the following description and claims, the following terms have the meanings indicated below:

[0018] The terms "on", "appended to", "affixed to", "bonded to", "adhered to", or terms of like import means that the designated item, e.g., a coating, component, or layer, iseither directly connected to (in contact with) the object surface, or indirectly connected to the object surface, e.g., through one or more other coatings, components, or layers.

[0019] FIG. 1 illustrates a schematic cross-sectional view of an example of an embossed floor covering 200 in accordance with the present disclosure.

[0020] The embossed floor coverings 200 of the present disclosure comprise (a) a substrate 202. Materials suitable for use as flooring substrates typically include polymers, metals, wood, composites, veneers and laminates. The substrate 202 often comprises polyvinylchloride, polyurethane, acrylic, melamine, and / or polyolefin. Note that the phrase “and / or” when used in a list is meant to encompass alternative examples including each individual component in the list as well as any combination of components. For example, the list “A, B, and / or C” is meant to encompass seven separate examples that include A, or B, or C, or A + B, or A + C, or B + C, or A + B + C.

[0021] The substrate 202 is typically in the form of a flat sheet that may be rolled, a plank, or tile, having two opposing surfaces. Thicknesses may vary depending on the type of flooring being prepared.

[0022] The embossed floor coverings 200 of the present disclosure further comprise(b) a decorative layer 203 applied to the substrate 202. The decorative layer 203 may be printed or transferred onto the surface of the substrate 202; alternatively, the decorative layer 203 comprises a film having a decorative pattern printed or transferred thereon, that is adhesively applied to the substrate 202 such as by using an adhesive as known in the art between the substrate 202 and the decorative layer 203. When the decorative layer is printed onto the surface of the substrate 202, the floor covering 200 may further comprise a primer layer 207 (FIG. 2) between the substrate 202 and the decorative layer 203, and the decorative layer 203 is printed onto the primer layer 207. Suitable primers include any of those known in the art.

[0023] The embossed floor coverings 200 of the present disclosure further comprise(c) a wear layer 201 applied to the decorative layer 203. The wear layer 201 is prepared from a curable coating composition, which comprises a (1 ) a reactive diluent having multiple (meth)acrylate functional groups. The term “(meth)acrylate” as used herein refers to acrylate and / or methacrylate functional groups. The reactive diluentcomprises at least 2, and at most 6, or at most 4, or at most 3 (meth)acrylate functional groups. For example, the reactive diluent may comprise 2 to 6, or 2 to 4, or 2 to 3 (meth)acrylate functional groups.

[0024] Examples of suitable reactive diluents include dipropylene glycol diacrylate, propoxylated neopentyl glycol diacrylate, trimethylolpropane triacrylate, a polyether triacrylate (for example, OTA-480, a triacrylated reactive diluent based on a glycerol derivative available from Allnex GMBH), ditrimethylolpropane triacrylate, pentaerythritol tetraacrylate, 2-ethylhexyl acrylate, cyclic trimethylolpropane formal acrylate, 1 ,6-hexanediol diacrylate, tripropylene glycol diacrylate and / or dipentaerythritol pentaacrylate.

[0025] The reactive diluent is typically present in the curable coating composition in an amount of at least 10 percent by weight, or at least 15 percent by weight, or at least 20 percent by weight, and at most 40 percent by weight, or at most 30 percent by weight, or at most 25 percent by weight, based on the total weight of the curable coating composition. For example, the reactive diluent may be present in the curable coating composition in an amount of 10 to 40 percent by weight, or 10 to 30 percent by weight, or 10 to 25 percent by weight, or 15 to 40 percent by weight, or 15 to 30 percent by weight, or 15 to 25 percent by weight, or 20 to 40 percent by weight, or 20 to 30 percent by weight, or 20 to 25 percent by weight, based on the total weight of the curable coating composition.

[0026] The curable coating composition further comprises (2) a free radical- polymerizable compound different from the reactive diluent (1 ). The free radical- polymerizable compound comprises at least 2, and at most 6, or at most 4, or at most 3 (meth)acrylate functional groups. For example, the free radical-polymerizable compound may comprise 2 to 6, or 2 to 4, or 2 to 3 (meth)acrylate functional groups.

[0027] The free radical-polymerizable compound further comprises a polyester- or polyurethane-functional linking group, wherein the polyester- or polyurethane- functional group is aliphatic. Often, the polyester- or polyurethane-functional group contains no aromatic functional groups. Usually, the free radical-polymerizable compound contains no aromatic functional groups. The polyurethane-functional group may be prepared from aliphatic polyisocyanates and polyols such that the reactionproduct has 2 to 6 free isocyanate and / or hydroxyl groups available to react with functional groups such as acid, hydroxyl, amino, and epoxy functional groups in a (meth)acrylic compound. Likewise, the polyester-functional group may be prepared from aliphatic polyacids and polyols such that the reaction product has 2 to 6 free acid and / or hydroxyl groups available to react with functional groups such as acid, hydroxyl, amino, and epoxy functional groups in a (meth)acrylic compound. Note that the prefix “(meth)” is intended to refer to either an acrylic group or a methacrylic group. The polyester- or polyurethane-functional linking group is thus typically multi-valent, by which is meant it is at least divalent.

[0028] Examples of suitable aliphatic polyisocyanates used to prepare a polyurethane- functional group include 4,4'-methylene-bis(cyclohexyl isocyanate), isophorone diisocyanate, an isomeric mixture of 2,2,4- and 2,4,4-trimethyl hexamethylene diisocyanate, 1 ,6-hexamethylene diisocyanate, and biurets and trimers thereof. Examples of suitable aliphatic polyacids used to prepare a polyester-functional group include succinic acid, adipic acid, azelaic acid, sebacic acid, maleic acid, fumaric acid, and trimellitic acid. Besides the polycarboxylic acids mentioned above, functional equivalents of the acids such as anhydrides where they exist or lower alkyl esters of the acids such as the methyl esters may be used. Examples of suitable aliphatic polyols used to prepare a a polyester- or polyurethane-functional linking group include ethylene glycol, propylene glycol, butylene glycol, 1 ,6-hexylene glycol, neopentyl glycol, diethylene glycol, glycerol, trimethylol propane, and pentaerythritol. Mixtures of any of the above reactants may also be used.

[0029] The polyester- or polyurethane-functional reaction products having free reactive functional groups may be reacted with functional groups on a suitable (meth)acrylic compound, such as (meth)acrylic acid, hydroxyethyl methacrylate, hydroxypropyl methacrylate, amino functional (meth)acrylates, and the like, to form the free radical-polymerizable compound used in the UV radiation-curable coating composition.

[0030] Examples of commercially available, suitable free radical-polymerizable compounds include aliphatic polyester and polyurethane acrylates sold under the name LAROMER from BASF; EBECRYL 4201 and 8702, aliphatic urethane acrylatesavailable from Allnex GMBH; and CN991 , a difunctional urethane acrylate available from Arkema, Inc. Often the free radical-polymerizable compound comprises two (meth)acrylate functional groups and an aliphatic polyurethane-functional group. Combinations of free radical-polymerizable compounds may also be used.

[0031] The free radical-polymerizable compound is typically present in the curable coating composition in an amount of at least 30 percent by weight, or at least 40 percent by weight, or at least 60 percent by weight, and at most 80 percent by weight, or at most 70 percent by weight, or at most 65 percent by weight, based on the total weight of the curable coating composition. For example, the free radical-polymerizable compound may be present in the curable coating composition in an amount of 30 to 80 percent by weight, or 30 to 70 percent by weight, or 30 to 65 percent by weight, or 40 to 80 percent by weight, or 40 to 70 percent by weight, or 40 to 65 percent by weight, or 60 to 80 percent by weight, or 60 to 70 percent by weight, or 60 to 65 percent by weight based on the total weight of the curable coating composition.

[0032] The curable coating composition may further comprise additives such as a photoinitiator, a defoamer, abrasion resistant particles such as aluminum oxide and silicon carbide, a filler, a dispersant, a flow / leveling agent, and / or an adhesion promoter, as known in the art. In certain examples, the UV radiation-curable coating composition further comprises white fused alumina particles having a grit size ( i. e., US grit size as per ANSI; according to manufacturer’s specification) of 120 to 360 grit, or 180 to 360 grit, or 240 to 360 grit, or 320 to 360 grit, present in the UV radiation- curable coating composition in an amount of 5 to 25 percent by weight, or 5 to 10 percent by weight, or 10 to 25 percent by weight, based on the total weight of the UV radiation-curable coating composition. Grit size may be determined using the Certified or Inspection Test Sieves, which each have a number corresponding to a size in the United States Standard Sieve Series, with screen openings specified by the ASTM E 11 -13 Standard Specification Table.

[0033] In certain examples, the curable coating composition is substantially free, essentially free, or completely free of a fluorine-functional (meth)acrylate compound. The terms “substantially free of [a given compound]” means that the composition contains less than 1000 parts per million (ppm) of the given compound; “essentiallyfree of [a given compound]” means that the composition contains less than 100 ppm of the given compound; and “completely free of [a given compound]” means that the composition contains less than 20 parts per billion (ppb) of the given compound. The weight is based on the total weight of the composition.

[0034] The curable coating compositions described herein are typically liquid at ambient temperature (for example, usually 20 to 25 °C, such as a typical room temperature, 72°F (22.2°C)). Any of the curable coating compositions described herein used to form the wear layer are typically 100% solids. “Solids”, or “nonvolatiles”, include any materials, whether solid or liquid at ambient temperature, that remain after subjecting a 1 -gram sample of the composition to 1 10°C for one hour.

[0035] The curable coating composition used to form the wear layer 201 is usually applied to the decorative layer 203 via roll coating, curtain coating, vacuum coating, or spray application. The thickness of the wear layer 201 is typically at least 100 microns, or at least 150 microns, and at most 250 microns, or at most 200 microns. For example, the thickness of the wear layer may range from 100 to 250 microns, or 100 to 200 microns, or 150 to 250 microns, or 150 to 200 microns. Multiple coats of the wear layer may be applied in order to obtain the desired film build (thickness).

[0036] In certain examples, the wear layer 201 may comprise (i) a preliminary layer 201 a applied to the decorative layer 203; and (ii) a second layer 201 b prepared from the UV radiation-curable coating composition and applied to the preliminary layer 201 a, as shown in FIG. 3. In such examples, the preliminary layer 201 a may be prepared from a UV radiation-curable coating composition that is the same as or different from that used to prepare the second layer 201 b. Usually the preliminary layer 201 a is designed to provide particular physical and / or aesthetic properties to the wear layer 201 , such as impact resistance, adhesion, shock absorption, and appearance. In certain examples, the preliminary layer 201 a comprises a matting agent such as silica. During digital embossing of the wear layer 201 , portions of a matte preliminary layer 201 a under a glossier second layer 201 b may be exposed to provide visual contrast with the second layer 201 b, enhancing the textured appearance of the embossed surface of the floor covering. After curing of such a preliminary layer 201 a and the UV radiation-curable coating composition(s) to form a cured preliminary layer201 a and a cured second layer 201 b, the cured preliminary layer 201 a demonstrates a 60° gloss less than a 60° gloss of the cured second layer 201 b. Gloss may be measured using a BYK® Micro-Tri-gloss 60° gloss meter. The gloss meter is placed onto the coated surface of a test panel parallel to the direction of the embossing pattern. The 60° gloss is read by pressing an operating button. This measuring process is repeated three times along the surface of the panel, and the average gloss is recorded, making sure the gloss is read parallel to the embossing pattern. The gloss of the cured preliminary layer is typically measured on the test panel prior to application of the second layer, and the gloss of the cured second layer is typically measured on the test panel after the second layer is applied on top of the preliminary layer.

[0037] The embossed floor coverings 200 of the present disclosure further comprise (d) an additional layer 204 on top of the wear layer 201. The additional layer may comprise a composition applied directly as a single layer to the wear layer 201. Alternatively, an intervening primer layer 209 (FIG. 2) may be applied to the wear layer 201 followed by one or more topcoat layers 204. The additional layer 204 is usually unpigmented (i. e., a clear coat), and at least a portion thereof is the outermost layer (topcoat) of the floor covering 200. Such layers contribute to scratch and stain resistance, and may be selected to provide any desired gloss level. The thickness of the additional layer 204 is typically 10 to 25 microns. Suitable compositions include any of those known in the art, such as those sold under the names Raycron and Claritage, available from PPG.

[0038] A texture is digitally embossed onto the floor covering 200 into the wear layer 201 before application of the additional layer 204. In an exemplary digital embossing process, an inhibitor solution as known in the art, such as a PVC plastisol, is applied by digital printing in a desired pattern on top of the wear layer 201 . The UV radiation- curable coating composition in the wear layer is subjected to curing conditions sufficient to partially cure the composition, after which the inhibitor layer and uncured coating composition are removed from the surface, such as by rinsing or by the use of a brush or other suitable removal tool or means, to form an embossed pattern. As noted above, if the wear layer includes both a preliminary layer 201 a and a second layer 201 b, during digital embossing of the wear layer 201 , portions of the preliminarylayer 201 a under the second layer 201 b may be exposed to provide visual enhancements to the embossed pattern.

[0039] When the additional layer 204 is subsequently applied, it conforms to the indentations 205 of the texture.

[0040] The embossed floor coverings 200 described herein can be prepared by a method comprising:(a) applying a decorative layer 203 to a flooring substrate 202, wherein the flooring substrate 202 comprises polyvinylchloride, polyurethane, acrylic, melamine, and / or polyolefin;(b) applying a wear layer 201 to the decorative layer 203, wherein the wear layer 201 is prepared from any of the UV radiation-curable coating compositions described above;(c) applying an inhibitor solution via digital printing in a pattern on top of the wear layer 201 ;(d) partially curing the UV radiation-curable coating composition by exposing the UV radiation-curable coating composition to UV or electron beam radiation;(e) removing the inhibitor layer and the UV radiation-curable coating composition that remains uncured, to form an embossed pattern in the wear layer 201 ;(f) applying an additional layer 204 on top of the wear layer 201 to form an embossed floor covering; and(g) conducting a final curing step to cure all layers and form an embossed floor covering.

[0041] The decorative layer 203 may comprise a film that is adhesively applied to the flooring substrate 202. Alternatively, a primer layer 207 may be applied between the flooring substrate 202 and the decorative layer 203, in which scenario the decorative layer 203 is printed onto the primer layer 207.

[0042] The curable coating composition may be applied to the decorative layer 203 by conventional means such as rolling, spraying, vacuum coating or curtain coating. Multiple coats of the curable coating composition the forms the wear layer 201 may be applied in order to obtain the desired film build (thickness). In certain examples, application of the wear layer 201 in step (b) comprises: (i) applying a preliminary layer201 a to the decorative layer 203; and (ii) applying a second layer 201 b prepared from the UV radiation-curable coating composition to the preliminary layer 201 a.

[0043] An inhibitor solution is applied on top of the wear layer 201 via digital printing in a desired pattern, after which the UV radiation-curable coating composition is partially cured to form a wear layer 201 by exposing the curable coating composition to ultraviolet (UV) or electron beam (EB) radiation. Subsequently, the inhibitor layer and the UV radiation-curable coating composition that remains uncured are removed, to form an embossed pattern in the wear layer 201 .

[0044] The term “cure”, “cured” or similar terms, as used in connection with a cured or curable composition, e.g., a “cured composition” of some specific description, means that at least a portion of any polymerizable and / or crosslinkable components that form the curable composition is polymerized and / or crosslinked. Additionally, curing of a composition refers to subjecting said composition to curing conditions such as those listed above, leading to the reaction of the reactive functional groups of the composition. The term “at least partially cured” means subjecting the composition to curing conditions, wherein reaction of at least a portion of the reactive groups of the composition occurs. The composition can also be subjected to curing conditions such that a substantially complete cure is attained and wherein further curing results in no significant further improvement in physical properties, such as hardness.

[0045] After exposing the curable coating composition to radiation, an additional layer 204 is applied on top of the embossed wear layer 201 using conventional means, to form a floor covering 200. Again, the additional layer 204 may comprise a composition applied directly as a single layer to the wear layer 201 , or an intervening primer layer 209 may be applied under the additional layer 204. If a primer layer 209 is used, it may be at least partially cured, usually by UV radiation, prior to application of the additional layer 204. A final curing step is usually performed after application of the additional layer 204 to cure all layers. Such curing may be achieved by exposing the curable coating composition(s) on the embossed floor covering to ultraviolet (UV) or electron beam (EB) radiation as above.

[0046] The present disclosure is also directed to the following aspects:1 . An embossed floor covering comprising:(a) a substrate comprising polyvinylchloride, polyurethane, acrylic, melamine, and / or polyolefin;(b) a decorative layer applied to the substrate;(c) a wear layer applied to the decorative layer, wherein the wear layer is prepared from a UV radiation-curable coating composition comprising:(1 ) a reactive diluent comprising 2 to 6 (meth)acrylate functional groups, present in the curable coating composition in an amount of at least 10 percent by weight and at most 40 percent by weight, based on the total weight of the curable coating composition; and(2) a free radical-polymerizable compound different from the reactive diluent (1 ), present in the curable coating composition in an amount of at least 30 percent by weight and at most 80 percent by weight, based on the total weight of the curable coating composition; wherein the free radical-polymerizable compound comprises:(i) 2 to 6 (meth)acrylate functional groups; and(ii) a polyester- or polyurethane-functional linking group; wherein the group (ii) is aliphatic; and(d) an additional layer on top of the wear layer (c), wherein a texture is digitally embossed into the wear layer prior to application of the additional layer.2. The floor covering according to aspect 1 , wherein the reactive diluent comprises 2 to 4 (meth)acrylate functional groups.3. The floor covering according to any preceding aspect, wherein the reactive diluent comprises 2 to 3 (meth)acrylate functional groups.4. The floor covering according to any preceding aspect, wherein the reactive diluent is present in the curable coating composition in an amount of at least at least 15 percent by weight, based on the total weight of the curable coating composition.5. The floor covering according to any preceding aspect, wherein the reactive diluent is present in the curable coating composition in an amount of at leastat least 20 percent by weight, based on the total weight of the curable coating composition.6. The floor covering according to any preceding aspect, wherein the reactive diluent is present in the curable coating composition in an amount of at most 30 percent by weight, based on the total weight of the curable coating composition.7. The floor covering according to any preceding aspect, wherein the reactive diluent is present in the curable coating composition in an amount of at most 25 percent by weight, based on the total weight of the curable coating composition.8. The floor covering according to any preceding aspect, wherein the free radical-polymerizable compound is present in the curable coating composition in an amount of at least 40 percent by weight, based on the total weight of the curable coating composition.9. The floor covering according to any preceding aspect, wherein the free radical-polymerizable compound is present in the curable coating composition in an amount of at least 60 percent by weight, based on the total weight of the curable coating composition.10. The floor covering according to any preceding aspect, wherein the free radical-polymerizable compound is present in the curable coating composition in an amount of at most 70 percent by weight, based on the total weight of the curable coating composition.11 . The floor covering according to any preceding aspect, wherein the free radical-polymerizable compound is present in the curable coating composition in an amount of at most 65 percent by weight, based on the total weight of the curable coating composition.12. The floor covering according to any preceding aspect, wherein the free radical-polymerizable compound comprises 2 to 4 (meth)acrylate functional groups.13. The floor covering according to any preceding aspect, wherein the free radical-polymerizable compound comprises 2 to 3 (meth)acrylate functional groups.14. The floor covering according to any preceding aspect, wherein the substrate (a) comprises polyvinylchloride.15. The floor covering according to any preceding aspect, wherein the decorative layer (b) comprises a film that is adhesively applied to the substrate (a).16. The floor covering according to any preceding aspect, further comprising a primer layer between the substrate (a) and the decorative layer (b), wherein the decorative layer is printed onto the primer layer.17. The floor covering according to any of the preceding aspects, wherein the wear layer comprises: (i) a preliminary layer applied to the decorative layer; and (ii) a second layer prepared from the UV radiation-curable coating composition and applied to the preliminary layer; and wherein after curing of the preliminary layer and the UV radiation-curable coating composition to form a cured preliminary layer and a cured second layer, the cured preliminary layer demonstrates a 60° gloss less than a 60° gloss of the cured second layer; wherein the 60° gloss is measured using a 60° gloss meter.18. The floor covering according to any of the preceding aspects, wherein the free radical-polymerizable compound comprises two (meth)acrylate functional groups and an aliphatic polyurethane-functional group.19. The floor covering according to any of the preceding aspects, wherein the reactive diluent (1) comprises dipropylene glycol diacrylate, propoxylated neopentyl glycol diacrylate, trimethylolpropane triacrylate, a polyether triacrylate,ditrimethylolpropane triacrylate, pentaerythritol tetraacrylate, 2-ethylhexyl acrylate, cyclic trimethylolpropane formal acrylate, 1 ,6-hexanediol diacrylate, tripropylene glycol diacrylate and / or dipentaerythritol pentaacrylate.20. The floor covering according to any of the preceding aspects, wherein the UV radiation-curable coating composition further comprises a photoinitiator, a defoamer, abrasion resistant particles selected from aluminum oxide particles and silicon carbide particles, a filler, a dispersant, a flow / leveling agent, and / or an adhesion promoter.21 . The floor covering according to any of the preceding aspects, wherein the UV radiation-curable coating composition further comprises white fused alumina particles having a grit size of 120 to 360 grit, present in the UV radiation-curable coating composition in an amount of 5 to 25 percent by weight, based on the total weight of the UV radiation-curable coating composition.22. The floor covering according to any of the preceding aspects, wherein the UV radiation-curable coating composition further comprises white fused alumina particles having a grit size of 180 to 360 grit.23. The floor covering according to any of the preceding aspects, wherein the UV radiation-curable coating composition further comprises white fused alumina particles having a grit size of 240 to 360 grit.24. The floor covering according to any of the preceding aspects, wherein the UV radiation-curable coating composition further comprises white fused alumina particles having a grit size of 320 to 360 grit.25. The floor covering according to any of the preceding aspects, wherein the UV radiation-curable coating composition further comprises white fused alumina particles present in the UV radiation-curable coating composition in an amount of 5 to10 percent by weight, based on the total weight of the UV radiation-curable coating composition.25. The floor covering according to any of the preceding aspects, wherein the UV radiation-curable coating composition further comprises white fused alumina particles present in the UV radiation-curable coating composition in an amount of 10 to 25 percent by weight, based on the total weight of the UV radiation-curable coating composition.26. The floor covering according to any of the preceding aspects, further comprising a primer layer between the wear layer (c) and the additional layer (d).27. The floor covering according to any of the preceding aspects, wherein the thickness of the wear layer is at least 100 microns and at most 250 microns.28. The floor covering according to any of the preceding aspects, wherein the thickness of the wear layer is at least 150 microns.29. The floor covering according to any of the preceding aspects, wherein the thickness of the wear layer is most 200 microns.30. The floor covering according to any of the preceding aspects, wherein the thickness of the additional layer ranges from 10 to 25 microns.31 . A method of preparing a digitally embossed floor covering comprising:(a) applying a decorative layer to a flooring substrate, wherein the flooring substrate comprises polyvinylchloride, polyurethane, acrylic, melamine, and / or polyolefin;(b) applying a wear layer to the decorative layer, wherein the wear layer is prepared from a UV radiation-curable coating composition comprising:(1) a reactive diluent comprising 2 to 6, (meth)acrylate functional groups, present in the curable coating composition in an amount of at least 10 percent byweight, and at most 40 percent by weight, based on the total weight of the curable coating composition; and(2) a free radical-polymerizable compound different from the reactive diluent (1 ), present in the curable coating composition in an amount of at least 30 percent by weight, and at most 80 percent by weight, based on the total weight of the curable coating composition; wherein the free radical-polymerizable compound comprises:(i) 2 to 6, (meth)acrylate functional groups; and(ii) a polyester- or polyurethane-functional linking group; wherein the group (ii) is aliphatic;(c) applying an inhibitor solution via digital printing in a pattern on top of the wear layer;(d) partially curing the UV radiation-curable coating composition by exposing the UV radiation-curable coating composition to UV or electron beam radiation;(e) removing the inhibitor layer and the UV radiation-curable coating composition that remains uncured, to form an embossed pattern in the wear layer;(f) applying an additional layer on top of the wear layer; and(g) conducting a final curing step to cure all layers and form an embossed floor covering.32. The method according to aspect 31 , wherein the reactive diluent comprises 2 to 4 (meth)acrylate functional groups.33. The method according to any of aspects 31 to 32, wherein the reactive diluent comprises 2 to 3 (meth)acrylate functional groups.34. The method according to any of aspects 31 to 33, wherein the reactive diluent is present in the curable coating composition in an amount of at least at least 15 percent by weight, based on the total weight of the curable coating composition.35. The method according to any of aspects 31 to 34, wherein the reactive diluent is present in the curable coating composition in an amount of at least at least 20 percent by weight, based on the total weight of the curable coating composition.36. The method according to any of aspects 31 to 35, wherein the reactive diluent is present in the curable coating composition in an amount of at most 30 percent by weight, based on the total weight of the curable coating composition.37. The method according to any of aspects 31 to 36, wherein the reactive diluent is present in the curable coating composition in an amount of at most 25 percent by weight, based on the total weight of the curable coating composition.38. The method according to any of aspects 31 to 37, wherein the free radical-polymerizable compound is present in the curable coating composition in an amount of at least 40 percent by weight, based on the total weight of the curable coating composition.39. The method according to any of aspects 31 to 38, wherein the free radical-polymerizable compound is present in the curable coating composition in an amount of at least 60 percent by weight, based on the total weight of the curable coating composition.40. The method according to any of aspects 31 to 39, wherein the free radical-polymerizable compound is present in the curable coating composition in an amount of at most 70 percent by weight, based on the total weight of the curable coating composition.41 . The method according to any of aspects 31 to 40, wherein the free radical-polymerizable compound is present in the curable coating composition in an amount of at most 65 percent by weight, based on the total weight of the curable coating composition.42. The method according to any of aspects 31 to 41 , wherein the free radical-polymerizable compound comprises 2 to 4 (meth)acrylate functional groups.43. The method according to any of aspects 31 to 42, wherein the free radical-polymerizable compound comprises 2 to 3 (meth)acrylate functional groups.44. The method according to any of aspects 31 to 43, wherein the decorative layer comprises a film and is adhesively applied to the flooring substrate.45. The method according to any of aspects 31 to 44, further comprising applying a primer layer between the flooring substrate and the decorative layer, wherein the decorative layer is printed onto the primer layer.46. The method according to any of aspects 31 to 45, wherein step (b) comprises: (i) applying a preliminary layer to the decorative layer; and (ii) applying a second layer prepared from the UV radiation-curable coating composition to the preliminary layer; wherein after curing of the preliminary layer and the UV radiation- curable coating composition to form a cured preliminary layer and a cured second layer, the cured preliminary layer demonstrates a 60° gloss less than a 60° gloss of the cured second layer; wherein the 60° gloss is measured using a 60° gloss meter.47. The method according to any of aspects 31 to 46, further comprising applying a primer layer between the wear layer and the additional layer.48. The method according to any of aspects 31 to 47, wherein the thickness of the wear layer is at least 100 microns and at most 250 microns.49. The method according to any of aspects 31 to 48, wherein the thickness of the wear layer is at least 150 microns and at most 250 microns.50. The method according to any of aspects 31 to 48, wherein the thickness of the wear layer is at least 100 microns and at most 200 microns.51 . The method according to any of aspects 31 to 50, wherein the thickness of the wear layer is at least 150 microns and at most 200 microns.52. The method according to any of aspects 31 to 51 , wherein the thickness of the additional layer ranges from 10 to 25 microns.53. The method according to any of aspects 31 to 52, wherein the free radical-polymerizable compound comprises two (meth)acrylate functional groups and an aliphatic polyurethane-functional group.

[0047] Whereas particular embodiments of this disclosure have been described above for purposes of illustration, it will be evident to those skilled in the art that numerous variations of the details of the present disclosure may be made without departing from the scope of the disclosure as defined in the appended claims.

Claims

WHAT IS CLAIMED IS:1 . A digitally embossed floor covering comprising:(a) a substrate comprising polyvinylchloride, polyurethane, acrylic, melamine, and / or polyolefin;(b) a decorative layer applied to the substrate;(c) a wear layer applied to the decorative layer, wherein the wear layer is prepared from a UV radiation-curable coating composition comprising:(1) a reactive diluent comprising 2 to 6 (meth)acrylate functional groups, present in the curable coating composition in an amount of at least 10 percent by weight and at most 40 percent by weight, based on the total weight of the curable coating composition; and(2) a free radical-polymerizable compound different from the reactive diluent (1 ), present in the curable coating composition in an amount of at least 30 percent by weight and at most 80 percent by weight, based on the total weight of the curable coating composition; wherein the free radical-polymerizable compound comprises:(i) 2 to 6 (meth)acrylate functional groups; and(ii) a polyester- or polyurethane-functional linking group; wherein the group (ii) is aliphatic; and(d) an additional layer on top of the wear layer (c), wherein a texture is digitally embossed into the wear layer prior to application of the additional layer.

2. The floor covering according to claim 1 , wherein the substrate (a) comprises polyvinylchloride.

3. The floor covering according to claim 1 or 2, wherein the decorative layer (b) comprises a film that is adhesively applied to the substrate (a).

4. The floor covering according to claim 1 or 2, further comprising a primer layer between the substrate (a) and the decorative layer (b), wherein the decorative layer is printed onto the primer layer.

5. The floor covering according to any of the preceding claims, wherein the wear layer comprises: (i) a preliminary layer applied to the decorative layer; and (ii) a second layer prepared from the UV radiation-curable coating composition and applied to the preliminary layer; and wherein after curing of the preliminary layer and the UV radiation-curable coating composition to form a cured preliminary layer and a cured second layer, the cured preliminary layer demonstrates a 60° gloss less than a 60° gloss of the cured second layer; wherein the 60° gloss is measured using a 60° gloss meter.

6. The floor covering according to any of the preceding claims, wherein the free radical-polymerizable compound comprises two (meth)acrylate functional groups and an aliphatic polyurethane-functional group.

7. The floor covering according to any of the preceding claims, wherein the reactive diluent (1 ) comprises dipropylene glycol diacrylate, propoxylated neopentyl glycol diacrylate, trimethylolpropane triacrylate, a polyether triacrylate, ditrimethylolpropane triacrylate, pentaerythritol tetraacrylate, 2-ethylhexyl acrylate, cyclic trimethylolpropane formal acrylate, 1 ,6-hexanediol diacrylate, tripropylene glycol diacrylate and / or dipentaerythritol pentaacrylate.

8. The floor covering according to any of the preceding claims, wherein the UV radiation-curable coating composition further comprises a photoinitiator, a defoamer, abrasion resistant particles selected from aluminum oxide particles and silicon carbide particles, a filler, a dispersant, a flow / leveling agent, and / or an adhesion promoter.

9. The floor covering according to any of the preceding claims, wherein the UV radiation-curable coating composition further comprises white fused alumina particles having a grit size of 120 to 360 grit, present in the UV radiation-curable coating composition in an amount of 5 to 25 percent by weight, based on the total weight of the UV radiation-curable coating composition.

10. The floor covering according to any of the preceding claims, further comprising a primer layer between the wear layer (c) and the additional layer (d).11 . The floor covering according to any of the preceding claims, wherein the thickness of the wear layer is at least 100 micronsand at most 250 microns.

12. The floor covering according to any of the preceding claims, wherein the thickness of the additional layer ranges from 10 to 25 microns.

13. A method of preparing a digitally embossed floor covering comprising:(a) applying a decorative layer to a flooring substrate, wherein the flooring substrate comprises polyvinylchloride, polyurethane, acrylic, melamine, and / or polyolefin;(b) applying a wear layer to the decorative layer, wherein the wear layer is prepared from a UV radiation-curable coating composition comprising:(1) a reactive diluent comprising 2 to 6 (meth)acrylate functional groups, present in the curable coating composition in an amount of at least 10 percent by weight, and at most 40 percent by weight, based on the total weight of the curable coating composition; and(2) a free radical-polymerizable compound different from the reactive diluent (1 ), present in the curable coating composition in an amount of at least 30 percent by weightand at most 80 percent by weight, based on the total weight of the curable coating composition; wherein the free radical-polymerizable compound comprises:(i) 2 to 6 (meth)acrylate functional groups; and(ii) a polyester- or polyurethane-functional linking group; wherein the group (ii) is aliphatic;(c) applying an inhibitor solution via digital printing in a pattern on top of the wear layer;(d) partially curing the UV radiation-curable coating composition by exposing the UV radiation-curable coating composition to UV or electron beam radiation;(e) removing the inhibitor layer and the UV radiation-curable coating composition that remains uncured, to form an embossed pattern in the wear layer;(f) applying an additional layer on top of the wear layer; and(g) conducting a final curing step to cure all layers and form an embossed floor covering.

14. The method according to claim 13, wherein the decorative layer comprises a film and is adhesively applied to the flooring substrate.

15. The method according to claim 13, further comprising applying a primer layer between the flooring substrate and the decorative layer, wherein the decorative layer is printed onto the primer layer.

16. The method according to any of claims 13 to 15, wherein step (b) comprises: (i) applying a preliminary layer to the decorative layer; and (ii) applying a second layer prepared from the UV radiation-curable coating composition to the preliminary layer; wherein after curing of the preliminary layer and the UV radiation- curable coating composition to form a cured preliminary layer and a cured second layer, the cured preliminary layer demonstrates a 60° gloss less than a 60° gloss of the cured second layer; wherein the 60° gloss is measured using a 60° gloss meter.

17. The method according to any of claims 13 to 16, further comprising applying a primer layer between the wear layer and the additional layer.

18. The method according to any of claims 13 to 17, wherein the thickness of the wear layer is at least 100 microns and at most 250 microns.

19. The method according to any of claims 13 to 18, wherein the thickness of the additional layer ranges from 10 to 25 microns.

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