Articles including polymeric sheets and coatings, and coated substrates including the same

Abstract

A coated substrate may comprise a transparent substrate and an article positioned on at least a portion of a first surface of the substrate. An article may comprise a polymeric sheet comprising a first surface and a second surface opposite the first surface. The polymeric sheet may comprise a neutralized ethylene acid copolymer material comprising carboxylic acid groups. The carboxylic acid groups of the ethylene acid copolymer may be at least partially neutralized with metallic ions. The article may further comprise a coating in direct contact with at least a portion of the first surface of the polymeric sheet. The coating may comprise an acrylic material. The coating may be an air-contacting layer.

Description

ARTICLES INCLUDING POLYMERIC SHEETS AND COATINGS, AND COATED SUBSTRATES INCLUDING THE SAMECROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Application Serial No. 63 / 520,239 filed August 17, 2023, the contents of which are incorporated in their entirety herein.TECHNICAL FIELD

[0002] The present disclosure relates to polymeric materials, and more specifically to coated polymeric sheets.BACKGROUND

[0003] Transparent substrates often lack adequate protective properties for their intended uses. For example, portable electronic devices, such as cell phones, often have large, valuable, and fragile screens. Extensive research has gone into developing less fragile screens and into screen protectors. Screen protectors may be applied to the screen at the factory or by the end user. In either case, screen protectors benefit from having acceptable adhesion to the screen, relatively high impact resistance, and / or relatively high hardness (to provide scratch resistance and / or cracking).BRIEF SUMMARY

[0004] There is a need for new articles that provide one or more of acceptable adhesion to the screen, relatively high impact resistance, and / or relatively high hardness. Such articles, in some embodiments, may be useful as screen protectors. As described herein, such articles may include a polymeric sheet and a coating in contact with the polymeric sheet. In particular, the polymeric sheet may comprise a neutralized ethylene acid copolymer that is at least partially neutralized with metallic ions, and the coating may comprise an acrylic material. Such a combination of materials may, in one or more embodiments, provide beneficial effects such as enhanced scratch resistance and / or impact resistance while maintaining suitable optical characteristics for a screen protector.

[0005] According to one or more embodiments, an article may comprise a polymeric sheet comprising a first surface and a second surface opposite the first surface. The polymeric sheet may comprise a neutralized ethylene acid copolymer material comprising carboxylic acid groups. The carboxylic acid groups of the ethylene acid copolymer may be at least partially neutralized with metallic ions. The article may further comprise a coating in direct contact with at least a portion of the first surface of the polymeric sheet. The coating may comprise an acrylic material. The coating may be an air-contacting layer.

[0006] According to one or more additional embodiments, a coated substrate may comprise a transparent substrate and an article. The article may be on at least a portion of a first surface of the substrate. The article may comprise a polymeric sheet comprising a first surface and a second surface opposite the first surface. The polymeric sheet may comprise a neutralized ethylene acid copolymer material comprising carboxylic acid groups. The carboxylic acid groups of the ethylene acid copolymer may be at least partially neutralized with metallic ions. The article may further comprise a coating in direct contact with at least a portion of the first surface of the polymeric sheet. The coating may comprise an acrylic material. The coating may be an air-contacting layer.

[0007] These and other embodiments are described in more detail in the Detailed Description. It is to be understood that both the foregoing general description and the following detailed description present embodiments of the presently disclosed technology, and are intended to provide an overview or framework for understanding the nature and character of the technology as it is claimed. The accompanying drawings are included to provide a further understanding of the presently disclosed technology and are incorporated into and constitute a part of this specification. The drawings illustrate various embodiments and, together with the description, serve to explain the principles and operations of the presently disclosed technology. Additionally, the drawings and descriptions are meant to be merely illustrative, and are not intended to limit the scope of the claims in any manner.BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0008] The following detailed description of specific embodiments of the present disclosure can be best understood when read in conjunction with the following drawings, where like structure is indicated with like reference numerals and in which:

[0009] FIG. 1 schematically depicts a cross-sectional view of an article, according to one or more embodiments described herein; and

[0010] FIG. 2 schematically depicts a cross-sectional view of another article, according to one or more embodiments described herein

[0011] Reference will now be made in greater detail to various embodiments, some embodiments of which are illustrated in the accompanying drawings. Whenever possible, the same reference numerals will be used throughout the drawings to refer to the same or similar parts.DETAILED DESCRIPTION

[0012] One or more embodiments of articles that comprise polymeric sheets and coatings are described herein. The configurations of the polymeric sheets and coatings, as well as the materials of such are generally described.

[0013] "Copolymer" is defined as a polymeric compound prepared by polymerizing multiple different types of monomers. Trace amounts of impurities (for example, catalyst residues) may be incorporated into and / or within the copolymer.

[0014] The term “percent neutralization” is defined as the degree of neutralization or ionization of the total acid moieties present in the neutralized ethylene acid copolymer material. Percent neutralization can range from 0 to greater than 100 percent. At zero percent, no ionization of the acid groups has occurred. At 100 percent, all the acid groups have been neutralized or ionized. When more than 100 percent of the acid groups are neutralized, the neutralization cations are loosely associated with the acid groups.

[0015] The term “haze” is defined as the percentage of transmitted light that, in passing through a film specimen, deviates from the incident beam by forward scattering. Haze may also be defined as a measure of the intensity of the transmitted light that is scattered more than 2.5° (presented as a percentage of the total transmitted light). Haze may appear as a milky, smoky, hazy field when looking through a film specimen. Low values are a measurement of low “haze”.

[0016] The present disclosure will now be described with reference to specific embodiments. As depicted in FIG. 1, a coated substrate 100 may comprise a transparent substrate 106 and an article108 positioned on at least a portion of a first surface of the substrate 106. The article 108 may comprise a polymeric sheet 104 comprising a first surface and a second surface opposite the first surface. The polymeric sheet 104 may comprise a neutralized ethylene acid copolymer material comprising carboxylic acid groups, wherein the carboxylic acid groups of the ethylene acid copolymer are at least partially neutralized with metallic ions. The article 108 may further comprise a coating 102 in direct contact with at least a portion of the first surface of the polymeric sheet 104. The coating 102 may comprise an acrylic material. The coating 102 may be an aircontacting layer. The article 108 may be suitable for attachment to a substrate 106 or may already be attached to the substrate 106, thereby forming a coated substrate 100.

[0017] Still referring to FIG. 1, in one or more embodiments, the polymeric sheet 104 may be positioned next to the coating 102. In embodiments, the polymeric sheet 104 may be in direct contact with the coating 102. In embodiments where the article 108 forms part of a coated substrate 100, the polymeric sheet 104 may be positioned between the coating 102 and the substrate 106. In embodiments, the polymeric sheet 104 may be in direct contact with the substrate 106. Alternatively, as depicted in FIG. 2, the polymeric sheet 104 may be separated from the substrate 106 by an adhesive layer 202. In embodiments of the article 108 where the article 108 is not positioned next to a substrate 106, the polymeric sheet 104 may be an air contacting layer. Alternatively, in embodiments of the article where the article 108 is not positioned next to a substrate 106, the polymeric sheet 104 may be positioned between an adhesive layer 202 and the coating 102, and the adhesive layer 202 may be an air contacting layer.

[0018] As mentioned previously herein, the polymeric sheet 104 may comprise a neutralized ethylene acid copolymer. The neutralized ethylene acid copolymer may be an ionomer. The neutralized ethylene acid copolymer may comprise ethylene and a carboxylic acid, such as those provided by an acrylic acid, a methacrylic acid, or both. The carboxylic acid functionalities may be at least partially neutralized with a metal, such as sodium, magnesium, lithium, or zinc. The term “base resin” refers to the composition of the ethylene acid copolymer before neutralization to form the neutralized ethylene acid copolymer. Weight percent acid (wt % acid) in the base resin is based upon the total weight of all a, P ethylenically unsaturated carboxylic acid monomers and ethylene in the base resin. Weight percent acid of the base resin is measured by Fourier Transform Infrared Spectrophotometry (FTIR Analysis) using standards calibrated by titration. The degree of neutralization may be measured by several techniques. Thus, infrared analysis may beemployed and the degree of neutralization calculated from the changes resulting in the absorption bands. Another method comprises the titration of a solution of the ionic copolymer with a strong base. Yet another method comprises X-ray fluorescence. All these methods are within the skill of one in the art.

[0019] The neutralized ethylene acid copolymer may comprise copolymerized units of ethylene and acrylic acid, methacrylic acid, or both. In embodiments, the neutralized ethylene acid copolymer may comprise from 70 wt. % to 85 wt. %, such as from 75 to 85 wt. %, from 80 wt. % to 85 wt. %, from 70 wt. % to 80 wt. %, from 70 wt. % to 75 wt. %, from 75 wt. % to 80 wt. %, or any subset thereof of copolymerized units of ethylene and from 15 wt. % to 30 wt. %, such as from 15 wt. % to 25 wt. %, from 15 wt. % to 20 wt. %, from 20 wt. % to 30 wt. %, from 25 wt. % to 30 wt. %, from 20 wt. % to 25 wt. %, or any subset thereof of copolymerized units of acrylic acid or methacrylic acid, based on the total polymer weight of the neutralized ethylene acid copolymer.

[0020] According to some embodiments, the neutralized ethylene acid copolymer may comprise carboxylic acid groups. The carboxylic acid groups may be derived from the acrylic acid, the methacrylic acid, the comonomer, or a combination of these. The carboxylic acid groups may be neutralized with one or more metal salts. The cations of the metal salts may be mono- valent, divalent, trivalent, or have higher valences. The metal salts may include alkali metal salts, such as sodium (Na) salts, potassium (K) salts, or both; alkali earth metal salts, such as beryllium (Be) salts, zinc (Zn), magnesium (Mg) salts, calcium (Ca) salts, strontium (Sr) salts, barium (Ba) salts, and radium (Ra) salts; cation salts, such as aluminum (Al) salts, chromium (Cr) salts, iron (Fe) salts, or lanthanide metal cation salts; or combinations of these. In embodiments, the metal salts may comprise sodium salts, magnesium salts, zinc salts, or combinations of these.

[0021] From 0.1 % to 100 % of the carboxylic acid groups of the neutralized ethylene acid copolymer may be neutralized by the metal salts. In embodiments, from 1 % to 100 %, from 5 % to 100 %, from 10 % to 100 %, from 20 % to 100 %, from 40 % to 100 %, from 60 % to 100 %, from 80 % to 100 %, from 0.1 % to 80 %, from 0.1 % to 60 %, from 0.1 % to 40 %, from 0.1 % to 20 %, from 5 % to 95 %, from 10 % to 90 %, from 20 % to 80 %, from 30 % to 70 %, from 30% to 60 %, from 20 % to 40 %, or any subset thereof of the carboxylic acid groups of the neutralized ethylene acid copolymer may be neutralized by the metal salts. In embodiments, from40 % to 70 % of the carboxylic acid groups of the neutralized ethylene acid copolymer may be neutralized with sodium cations.

[0022] In the context of this disclosure, the percent neutralization is presented using the assumption that each cation will react with the maximum number of carboxylic acid groups calculated from its ionic charge. That is, it is assumed, for example, that Al3+will react with three carboxylic acid groups, that Mg2+and Zn2+will react with two, and that Na+will react with one. The neutralization level can be calculated according to the following equation: total cation valence > „Neutralization Level 100 total acid valence

[0023] In embodiments, the neutralized ethylene acid copolymer may further comprise 1 wt. % to 35 wt. % of a comonomer, on the basis of the total polymer weight of the neutralized ethylene acid copolymer. The comonomer may comprise carbon monoxide, sulfur dioxide, acrylonitrile, maleic anhydride, maleic acid diesters, maleic acid, maleic acid monoesters, itaconic acid, fumaric acid, fumaric acid monoester, a salt of these acids, glycidyl acrylate, glycidyl methacrylate, and glycidyl vinyl ether, methyl acrylate, ethyl acrylate, isopropyl acrylate, butyl acrylate, pentyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate and butyl methacrylate, pentyl methacrylate, or combinations thereof. In embodiments, the neutralized ethylene acid copolymer may comprise from 1 wt. % to 30 wt. %, from 1 wt. % to 25 wt. %, from 1 wt. % to 20 wt. %, from 1 wt. % to 15 wt. %, from 1 wt. % to 10 wt. %, from 1 wt. % to 5 wt. %, from 5 wt. % to 35 wt. %, from 10 wt. % to 35 wt. %, from 15 wt. % to 35 wt. %, from 20 wt. % to 35 wt. %, from 25 wt. % to 35 wt. %, from 30 wt. % to 35 wt. %, from 5 wt. % to 30 wt. %, from 10 wt. % to 25 wt. %, from 15 wt. % to 20 wt. %, or any subset thereof of the comonomer, on the basis of the total polymer weight of the neutralized ethylene acid copolymer.

[0024] The neutralized ethylene acid copolymer may have a melt flow index (h) of from 0.1 g / 10 min to 6 g / 10 min, as measured according to ASTM D1238. In embodiments, the neutralized ethylene acid copolymer may have a melt flow index (I2) of from 0.9 g / 10 min to 13 g / 10 min, from 0.9 g / 10 min to 10 g / 10 min, from 0.9 g / 10 min to 5 g / 10 min, from 0.9 g / 10 min to 6 g / 10 min, from 1 g / 10 min to 6 g / 10 min, from 2 g / 10 min to 10 g / 10 min, from 4 g / 10 min to 6 g / 10 mins, from 0.1 g / 10 min to 5 g / 10 min, from 0.1 g / 10 min to 4.75 g / 10 min, from 0.5 g / 10 min to4.5 g / 10 min, or any subset thereof. Melt flow index (I2) is measured at 190 °C and 2.16 kg, according to ASTM DI 238.

[0025] The neutralized ethylene acid copolymer may have a density of from 0.1 g / cm3to 2 g / cm3, from 0.5 g / cm3to 1.5 g / cm3, from 0.8 g / cm3to 1.2 g / cm3, from 0.9 g / cm3to 1.1 g / cm3, from 0.9 g / cm3to 1.0 g / cm3, from 0.95 g / cm3to 1.0 g / cm3, from 0.96 g / cm3to 0.98 g / cm3, or any subset thereof. Density is measured according to ASTM D792.

[0026] Suitable neutralized ethylene acid copolymers for use in the polymeric sheet 104 may be purchased from Dow. Inc. (Midland, Mi) under the trade name SURTYN™.

[0027] Still referring to FIG. 1, the polymeric sheet 104 may comprise at least 50 wt. % of the neutralized ethylene acid copolymer. In embodiments, the polymeric sheet 104 may comprise at least 60 wt. %, at least 75 wt. %, at least 90 wt. %, at least 95 wt. %, at least 99 wt. %, or even at least 99.9 wt. % of the neutralized ethylene acid copolymer, on the basis of the total weight of the polymeric sheet 104.

[0028] The polymeric sheet 104 may have a thickness of from 0.01 mm to 0.51 mm. The thickness of the polymeric sheet 104 should be selected such that it has sufficient thickness to provide impact protection while remaining thin enough to ensure optical transparency. In embodiments, the polymeric sheet 104 may have a thickness of from 0.05 mm to 0.51 mm, from 0.1 mm to 0.51 mm, from 0.15 mm to 0.51 mm, from 0.18 mm to 0.51 mm, from 0.2 mm to 0.51 mm, from 0.01 mm to 0.4 mm, from 0.01 mm to 0.35 mm, from 0.01 mm to 0.3 mm, from 0.05 mm to 0.45 mm, from 0.1 mm to 0.4 mm, from 0.15 mm to 0.35 mm, from 0.2 mm to 0.3 mm, or any subset thereof.

[0029] The article 108 may comprise a polymeric sheet 104 comprising a first surface and a second surface, and a coating 102 in direct contact with at least a portion of the first surface. In embodiments, no additional layers, such as a primer layer, may be present between the polymeric sheet 104 and the coating 102. The coating 102 may be an air contacting layer (e.g. the coating 102 may be an exterior layer with no further layers disposed thereon).

[0030] The coating 102 may comprise an acrylic material. Without being limited by theory, some embodiments of the acrylic material in the coating 102 may provide hardness, scratchprotection, and moisture protection to the a neutralized ethylene acid copolymer material in the polymeric sheet 104. In embodiments, the coating 102 may comprise at least 80 wt. %, at least 90 wt. %, at least 95 wt. %, at least 99 wt. %, or even at least 99.9 wt. % of the acrylic material, on the basis of the total weight of the coating 102.

[0031] The acrylic material may comprise ethyl acrylate (EA) and methyl methacrylate(MMA). In embodiments, the acrylic material may further comprise hydroxyl-ethyl methacrylate (HEMA). In embodiments, the acrylic material may further comprise itaconic acid. In embodiments, the acrylic material may comprise from 20 wt. % to 80 wt. % % of ethyl acrylate (EA), such as from 20 wt. % to 70 wt. %, from 20 wt. % to 60 wt. %, from 20 wt. % to 50 wt. %, from 20 wt. % to 40 wt. %, from 30 wt. % to 80 wt. %, from 40 wt. % to 80 wt. %, from 50 wt. % to 80 wt. %, from 60 wt. % to 80 wt. %, from 30 wt. % to 70 wt. %, from 40 wt. % to 60 wt. %, or any subset thereof of ethyl acetate, on the basis of the total weight of the acrylic material. In embodiments, the acrylic material may comprise from 15 wt. % to 75 wt. % methyl methacrylate, such as from 15 wt. % to 65 wt. %, from 15 wt. % to 55 wt. %, from 15 wt. % to 45 wt. %, from 15 wt. % to 35 wt. %, from 25 wt. % to 75 wt. %, from 35 wt. % to 75 wt. %, from 45 wt. % to 75 wt. %, from 55 wt. % to 75 wt. %, from 25 wt. % to 65 wt. %, from 35 wt. % to 55 wt. %, or any subset thereof of methyl methacrylate, on the basis of the total weight of the acrylic material. In embodiments, the acrylic material may comprise from 0 wt. % to 20 wt. % of HEMA, such as from 0 wt. % to 17.5 wt. %, from 0 wt. % to 15 wt. %, from 0 wt. % to 12.5 wt. %, from 0 wt. % to 10 wt. %, from 0 wt. % to 7.5 wt. %, from 0 wt. % to 5 wt. %, from 0 wt. % to 2.5 wt. %, from 0.1 wt. % to 20 wt. %, from 1 wt. % to 20 wt. %, from 2.5 wt. % to 20 wt. %, from 5 wt. % to 20 wt. %, from 7.5 wt. % to 20 wt. %, from 10 wt. % to 20 wt. %, from 2.5 wt. % to 17.5 wt. %, from 5 wt. % to 15 wt. %, or any subset thereof of HEMA, on the basis of the total weight of the acrylic material. In embodiments, the acrylic material may comprise from 0 wt. % to 20 wt. % of itaconic acid, such as from 0 wt. % to 17.5 wt. %, from 0 wt. % to 15 wt. %, from 0 wt. % to 12.5 wt. %, from 0 wt. % to 10 wt. %, from 0 wt. % to 7.5 wt. %, from 0 wt. % to 5 wt. %, from 0 wt. % to 2.5 wt. %, from 0.1 wt. % to 20 wt. %, from 1 wt. % to 20 wt. %, from 2.5 wt. % to 20 wt. %, from 5 wt. % to 20 wt. %, from 7.5 wt. % to 20 wt. %, from 10 wt. % to 20 wt. %, from 2.5 wt. % to 17.5 wt. %, from 5 wt. % to 15 wt. %, or any subset thereof of itaconic acid, on the basis of the total weight of the acrylic material. In embodiments, the acrylic material may comprise from 0.1 wt. % to 10 wt. % ofHEMA, from 15 wt. % to 30 wt. % of MMA, from 15 wt. % to 30 wt. % of EA, and from 01. wt. % to 10 wt. % of itaconic acid.

[0032] The acrylic material may be formed from the reaction product of an acrylic emulsion, such as a self-crosslinking acrylic emulsion. The self-crosslinking acrylic emulsion may be aqueous. The self-crosslinking acrylic emulsion may further comprise an adhesion promoter. The adhesion promoter may comprise an amino-functional silane, an alkoxysilane, or both. The alkoxy silane may comprise a mono-functional, a di-functional, a tri-functional alkoxy silane, or a combination of these.

[0033] The acrylic material may have a glass transition temperature of from 10 °C to 50 °C, such as from 10 °C to 40 °C, from 10 °C to 30 °C, from 10 °C to 20 °C, from 20 °C to 50 °C, from 30 °C to 50 °C, from 40 °C to 50 °C, from 20 °C to 40 °C, or any subset thereof.

[0034] Suitable commercially available acrylic materials include RHOPLEX™ ECO- 100, available from Dow Inc. (Midland, Michigan, USA).

[0035] In one or more embodiments, the acrylic material may comprise butyl acrylate (BA) and methyl methacrylate (MMA0. In embodiments, the acrylic material may further comprise one or more of hydryoxyl-ethyl methacrylate (HEMA), styrene, and a polyisocyanate. In embodiments, the acrylic material may comprise from 10 wt. % to 80 wt. % of butyl acrylate (BA), from 15 wt. % to 75 wt. % methyl methacrylate (MMA), from 0 wt. % to 20 wt. % of hydroxyl-ethyl methacrylate (HEMA), from 0 wt. to 20 wt. % styrene; and from 1 wt. % to 20 wt. % of a polyisocyanate, on the basis of the total weight of the acrylic material. In embodiments, the acrylic material may comprise from 0 wt. % to 15 wt. %, from 0 wt. % to 10 wt. %, from 0 wt. % to 5 wt. %, from 1 wt. % to 20 wt. %, from 1 wt. % to 15 wt. %, from 1 wt. % to 10 wt. %, from 2.5 wt. % to 20 wt. %, from 2.5 wt. % to 10 wt. %, from 2.5 wt. % to 5 wt. %, or any subset thereof of HEMA, on the basis of the total weight of the acrylic material. In embodiments, the acrylic material may comprise from 10 wt. % to 70 wt. %, from 10 wt. % to 50 wt. %, from 10 wt. % to 30 wt. %, from 10 wt. % to 20 wt. %, from 10 wt. % to 15 wt. %, or any subset thereof of BA, on the basis of the total weight of the acrylic material. In embodiments, the acrylic material may comprise from 10 wt. % to 75 wt. %, from 10 wt. % to 50 wt. %, from 10 wt. % to 30 wt. %, from 15 wt. % to 75 wt. %, from 15 wt. % to 50 wt.%, from 15 wt. % to 30 wt. %, from 20 wt. % to 75 wt. %, from 20 wt. % to 50 wt. %, from 20 wt. % to 30 wt. %, from 10 wt. % to 30 wt. %, or any subset thereof of MMA, on the basis of the total weight of the acrylic material. In embodiments, the acrylic material may comprise from 0 wt. % to 20 wt. %, from 0 wt. % to 15 wt. %, from 0 wt. % to 10 wt. %, from 0 wt. % to 5 wt. %, from 1 wt. % to 20 wt. %, from 1 wt. % to 10 wt. %, from 1 wt. % to 5 wt. %, from 1 wt. % to 2.5 wt. %, or any subset thereof of styrene, on the basis of the total weight of the acrylic material. In embodiments, the acrylic material may comprise from 1 wt. % to 18 wt. %, from 1 wt. % to 15 wt. %, from 1 wt. % to 13 wt. %, from 1 wt. % to 10 wt. %, from 1 wt. % to 7.5 wt. %, from 1 wt. % to 5 wt. % of the polyisocyanate, on the basis of the total weight of the acrylic material. In embodiments, the acrylic material may further comprise a methacrylic acid, such as from 0 wt. % to 10 wt. %, from 0 wt. % to 7.5 wt. %, from 0 wt. % to 5 wt. %, from 0 wt. % to 2.5 wt. %, from 0.1 wt. % to 10 wt. %, from 0.1 wt. % to 5 wt. %, from 0.1 wt. % to 2.5 wt. %, from 1 wt. % to 10 wt. %, from 1 wt. % to 5 wt. %, from 1 wt. % to 2.5 wt. %, or any subset thereof of the methacrylic acid. In embodiments, the acrylic material may comprise from 0 wt. % to 10 wt. % of the HEMA, from 10 wt. % to 30 wt. % of the BA, from 10 wt. % to 30 wt. % of the MMA, from 0 wt. % to 10 wt. % of styrene, and from 0 wt. % to 10 wt. % of the methacrylic acid.

[0036] Suitable commercially available acrylic materials include RHOSHIEED™ 3275, available from Dow Inc. (Midland, Michigan, USA).

[0037] The acrylic material may be applied in a relatively thin fdm, such as by spray coating, dip coating, or placing a droplet of acrylic material on the surface of the polymeric sheet 104. In embodiments, the surface of the polymeric sheet 104 may be treated by corona discharge before application of the acrylic material. Although the disclosed acrylic materials have relatively strong adhesion to the neutralized ethylene acid copolymer layer even without corona discharge treatment, in certain instances the anchorage may be further improved if the neutralized ethylene acid copolymer is corona treated before coating. Corona treatment in some cases will further improve the anchorage of the coating 102 to the polymeric sheet. Corona treatment can, for example, be carried out just before coating the polymeric sheet 104.

[0038] The coating 102 may have a thickness of from 0.2 pm to 20 pm, such as from 0.2 pm to 15 pm, from 0.2 pm to 10 pm, from 0.2 to 8 pm, from 0.2 pm to 6 pm, from 1 pm to 20 pm, from1 pm to 15 pm, from 1 m to 10 pm, from 1 to 8 pm, from 2 pm to 20 pm, from 2 pm to 15 pm, from 2 pm to 10 pm, from 2 pm to 8 pm, from 2 pm to 6 pm, or any subset thereof.

[0039] The article 108 may have a coating 102 equivalent weight of from 0.3 grams per square centimeter (gsm) to 32 gsm, such as from 0.5 gsm to 32 gsm, from 1 gsm to 32 gsm, from 2 gsm to 32 gsm, from 4 gsm to 32 gsm, from 8 gsm to 32 gsm, from 16 gsm to 32 gsm, from 24 gsm to 32 gsm, from 0.5 gsm to 25 gsm, from 0.5 gsm to 20 gsm, from 0.5 gsm to 15 gsm, from 0.5 gsm to 10 gsm, from 0.5 gsm to 5 gsm, from 2 gsm to 25 gsm, from 4 gsm to 20 gsm, from 6 gsm to 15 gsm, or any subset thereof.

[0040] As depicted in FIG. 2, the article 108 may include a polymeric sheet 104, a coating 102, and an adhesive layer 202. The adhesive layer 202 may be positioned on a second surface of the polymeric sheet 104, opposite the surface of the polymeric sheet 104 which is in contact with the coating 102. In some embodiments, the article 108 may be adhered to a substrate 106 by the adhesive layer 202. In other embodiments, such as those without a substrate 106, the adhesive layer 202 may be an air contacting layer.

[0041] The adhesive layer 202 may comprise a pressure sensitive adhesive (PSA). The pressure sensitive adhesive may comprise an acrylic PSA. The acrylic PSA may comprise one or more acrylate compounds. The one or more acrylate compounds may comprise one or more of 2- ethylhexyl-acrylate (2-EHA), ethyl acrylate and butyl acrylate (BA). In embodiments, the one or more acrylate compounds may comprise of 2-ethylhexyl-acrylate (2-EHA), ethyl acrylate and butyl acrylate (BA). In embodiments, the acrylic PSA may comprise from 10 wt. % to 80 wt. % of 2-ethylhexyl-acrylate (2-EHA), from 10 wt. % to 75 wt. % of ethyl acrylate, from 0 wt. % to 20 wt. % of butyl acrylate (BA), on the basis of the total weight of the acrylic PSA. The adhesive layer 202 may comprise at least 80 wt. %, such as at least 90 wt. %, at least 95 wt. %, at least 99 wt. %, or even at least 99.9 wt. % of the acrylic PSA.

[0042] The article 108 may be transparent. As used herein, a transparent material is one which allows a viewer to see objects on the other side clearly. Transparency can be quantified as the clarity of the material and the haze of the material.

[0043] At a protective thickness, the article 108 may have an average Gardner clarity of at least80 %, as determined by ASTM DI 746. In embodiments, at a protective thickness, the article 108may have an average Gardner clarity of at least 82 %, at least 84 %, at least 86 %, at least 88 %, at least 90 %, or at least 92 %, as determined by ASTM DI 746. Alternatively, the clarity may be measured as the Zebedee clarity, as determined according to ASTM DI 746. The article 108 may have an average Zebedee clarity of at least 10 %, such as at least 15 %, at least 20 %, at least 25 %, or at least 28 %. A protective thickness may be at least 0.1 mm, such as at least 0.12 mm, at least 0.14 mm, at least 0.16 mm, at least 0.18 mm, or at least 0.2 mm, from 0.01 mm to 3 mm, from 0.1 mm to 3 mm, from 0.1 mm to 1.5 mm, from 0.1 mm to 1 mm, from 0.1 mm to 0.5 mm, from 0.1 mm to 0.3 mm, from 0.2 mm to 0.3 mm, or any subset thereof.

[0044] At a protective thickness, the article 108 may have a haze of less than 20 %, as measured by ASTM DI 003. In embodiments, at a protective thickness, the article 108 may have a haze of less than 18 %, less than 16 %, less than 12 %, less than 10 %, less than 8 %, less than 6 % less than 4 %, less than 3 %, or even less than 2 %, as measured by ASTM DI 003.

[0045] At a protective thickness, the article 108 may have a Spencer Dart Impact resistance of at least 1500 grams force (gf), according to ASTM D3420. In embodiments, at a protective thickness, the article 108 may have a Spencer Dart Impact resistance of at least 2000 gf, at least 2200 gf, at least 2400 gf, at least 2800 gf, at least 3000 gf, at least 3250 gf, at least 3500 gf, at least 3750 gf, at least 4000 gf, at least 4250 gf, at least 4500 gf, at least 4750 gf, or at least 5000 gf-

[0046] The article 108 may have a hardness of at least 5B, as measured according to ASTM D3363-20. It should be understood that the hardness is measured on the air contacting surface of the coating 102. In embodiments, the article 108 may have a hardness of at least 4B, at least 3B, at least 2B, at least B, or at least HB. On the ASTM D3363-20 hardness scale, hardness goes from 6B (softest) to 9H (hardest).

[0047] The article 108 may principally comprise the polymeric sheet 104 and the coating 102. In embodiments, the polymeric sheet 104 and the coating 102 may comprise at least 95%, such as at least 98 %, at least 99 %, or even 99.9% of a thickness of the article 108. In embodiments, the polymeric sheet 104, the coating 102 and the adhesive layer 202 may comprise at least 95%, such as at least 98 %, at least 99 %, or even 99.9% of a thickness of the article 108.

[0048] In embodiments, the coated substrate 100 and the article 108 may lack a primer layer. In embodiments, the article 108 may comprise less than 1 wt. %, such as less than 0.5 wt. %, less than 0.1 wt. %, less than 0.01 wt. %, or even less than 0.001 wt. % of a primer layer. The primer layer may comprise an epoxy material. Without being limited by theory, it is believed that primer layers may degrade the transparency of the article 108.

[0049] The method of making the article 108 is not particularly limited, as each of the layers of the article 108 may be made by any suitable method known to one skilled in this art or yet to be discovered. For example, according to embodiments, the individual layers and the article 108 can be cast, extruded, co-extruded, laminated, and / or the like, including orientation (either uniaxially or biaxially) by various methodologies (e.g., blown fdm, mechanical stretching or the like).

[0050] The substrate 106 may comprise glass. In embodiments, the substrate 106 may be a cover glass for an electronic device.TESTING METHODS

[0051] Haze

[0052] Haze is measured according to ASTM DI 003.

[0053] Gardner Clarity

[0054] Gardner clarity is measured according to ASTM DI 746.

[0055] Zebedee Clarity

[0056] Zebedee clarity is measured according to ASTM DI 746.

[0057] Melt .Flow .index ..(I2)

[0058] Melt Flow Index I2 is measured according to ASTM D1238 at 190 °C and 2.16 kg.

[0059] Density

[0060] Density is measured according to ASTM D792.

[0061] Spencer Dart Impact

[0062] Spencer Dart Impact resistance is measured according to ASTM D3420.

[0063] Hardness

[0064] Hardness is measured according to ASTM D3363-20.

[0065] Glass Transition Temperature

[0066] Glass transition temperature is measured according to ASTM D3418.ASPECTS

[0067] According to a first aspect, an article may comprise a polymeric sheet comprising a first surface and a second surface opposite the first surface, the polymeric sheet comprising a neutralized ethylene acid copolymer material comprising carboxylic acid groups, wherein the carboxylic acid groups of the ethylene acid copolymer are at least partially neutralized with metallic ions; and a coating in direct contact with at least a portion of the first surface of the polymeric sheet, the coating comprising an acrylic material, wherein the coating is an air-contacting layer.

[0068] According to a second aspect, in conjunction with the first aspect, the combination of the polymeric sheet and the coating may comprise at least 95% of a thickness of the article.

[0069] According to a third aspect, in conjunction with the first or second aspects, the polymeric sheet may have a thickness measured as a distance between the first surface and the second surface, and the thickness may be from 0.01 mm to 0.51 mm.

[0070] According to a fourth aspect, in conjunction with any one of aspects 1-3, the ratio of a surface area of the first surface to a thickness of the article may be at least 100,000 mm.

[0071] According to a fifth aspect, in conjunction with any one of aspects 1-4, the coating may have a thickness of from 2 pm to 8 pm.

[0072] According to a sixth aspect, in conjunction with any one of aspects 1-5, the article may further comprise an adhesive layer in direct contact with the second surface of the polymeric sheet.

[0073] According to a seventh aspect, in conjunction with any one of aspects 1-6, the neutralized ethylene acid copolymer material may comprise from 1 wt. % to 35 wt. % of a comonomer comprising carbon monoxide, sulfur dioxide, acrylonitrile, maleic anhydride, maleic acid diesters, maleic acid, maleic acid monoesters, itaconic acid, fumaric acid, fumaric acid monoester, a salt of these acids, glycidyl acrylate, glycidyl methacrylate, and glycidyl vinyl ether, methyl acrylate, ethyl acrylate, isopropyl acrylate, butyl acrylate, pentyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate and butyl methacrylate, pentyl methacrylate, or combinations thereof.

[0074] According to an eighth aspect, in conjunction with any one of aspects 1-7, the neutralized ethylene acid copolymer material may be an ethylene methacrylic acid copolymer in which methacrylic acid groups of the copolymer are at least partially neutralized with sodium ions.

[0075] According to a ninth aspect, in conjunction with any one of aspects 1-8, the neutralized ethylene acid copolymer material may comprise from 15% to 30% by weight copolymerized units of acrylic acid or methacrylic acid, and 70% to 85% by weight copolymerized units of ethylene, based on the total weight of the neutralized acid copolymer; and about 40% to about 70% of carboxylic acid groups of the neutralized acid copolymer are neutralized as carboxylic acid salts comprising sodium cations.

[0076] According to a tenth aspect, in conjunction with any one of aspects 1-9, the neutralized ethylene acid copolymer material may have a melt flow index (I2) of from 0.9 g / 10 min to 13 g / 10 min, as measured by ASTM DI 238.

[0077] According to an eleventh aspect, in conjunction with any one of aspects 1-10, the acrylic material may comprise from 20 wt. % to 80 wt. % of ethyl acrylate (EA), from 15 wt. % to 75 wt. % methyl methacrylate (MMA), from 0 wt. % to 20 wt. % of hydroxyl-ethyl methacrylate (HEMA), and from 0 wt. to 20 wt. % itaconic acid; on the basis of the total weight of the acrylic material.

[0078] According to a twelfth aspect, in conjunction with any one of aspects 1-11, the acrylic material may comprise from 10 wt. % to 80 wt. % of butyl acrylate (BA), from 15 wt. % to 75 wt. % methyl methacrylate (MMA), from 0 wt. % to 20 wt. % of hydroxyl-ethylmethacrylate (HEMA), from 0 wt. to 20 wt. % styrene; and from 1 wt. % to 20 wt. % of a polyisocyanate, on the basis of the total weight of the acrylic material.

[0079] According to a thirteenth aspect, in conjunction with any one of aspects 1-12, the article may be a screen protector.

[0080] According to a fourteenth aspect, a coated substrate may comprise: a transparent substrate; and an article positioned on at least a portion of a first surface of the substrate, the article may comprise: a polymeric sheet comprising a first surface and a second surface opposite the first surface, the polymeric sheet comprising a neutralized ethylene acid copolymer material comprising carboxylic acid groups, wherein the carboxylic acid groups of the ethylene acid copolymer are at least partially neutralized with metallic ions; and a coating in direct contact with at least a portion of the first surface of the polymeric sheet, the coating comprising an acrylic material, wherein the coating is an air-contacting layer.

[0081] According to a fifteenth aspect, in conjunction with aspect 14, the substrate may comprise glass.EXAMPLES

[0082] The following examples are provided to illustrate embodiments described in this disclosure and are not intended to limit the scope of this disclosure or its appended claims.

[0083] Materials

[0084] PS-1 is a neutralized ethylene acid copolymer as described herein, with a melt flow rate (190°C / 2.16kg) of 4.5 g / 10 min (ASTM D1238) and a density of 0.970 g / cc (ASTM D792). The production of PS-1 is described in U.S. Patent No. 3264272, the entirety of which is incorporated by reference herein.

[0085] PS-2 is a neutralized ethylene acid copolymer as described herein, with a melt flow rate (190°C / 2.16kg) of 1.8 g / 10 min (ASTM D1238) and a density of 0.950 g / cc (ASTM D792). The production of PS-2 is described in U.S. Patent No. 3264272, the entirety of which is incorporated by reference herein.

[0086] PS-3 is a neutralized ethylene acid copolymer as described herein, with a melt flow rate (190°C / 2.16kg) of 0.7 g / 10 min (ASTM D1238) and a density of 0.970 g / cc (ASTM D792). PS- 3 is a highly branched a neutralized ethylene acid copolymer produced via random free-radical polymerization. The production of PS-3 is described in U.S. Patent No. 3264272, the entirety of which is incorporated by reference herein.

[0087] PS-4 is a neutralized ethylene acid copolymer as described herein, with a melt flow rate (190°C / 2.16kg) of 4.5 g / 10 min (ASTM D1238) and a density of 0.970 g / cc (ASTM D792). The production of PS-4 is described in U.S. Patent No. 3264272, the entirety of which is incorporated by reference herein.

[0088] COATING- 1 is an acrylic material formed from a water based acrylic latex with 42% solid and hydroxyl equivalent weight of 2600, as supplied. Once cured, the acrylic material of COATING-1 comprises from 10 wt. % to 80 wt. % of butyl acrylate (BA), from 15 wt. % to 75 wt. % methyl methacrylate (MMA), from 0 wt. % to 20 wt. % of hydroxyl-ethyl methacrylate (HEMA), from 0 wt. to 20 wt. % styrene, on the basis of the total weight of the acrylic material.

[0089] COATING-2 is an acrylic material formed from a self-crosslinking aqueous emulsion. Once cured, the acrylic material of COATING-2 comprises from 20 wt. % to 80 wt. % of ethyl acrylate (EA), from 15 wt. % to 75 wt. % methyl methacrylate (MMA), from 0 wt. % to 20 wt. % of hydroxyl-ethyl methacrylate (HEMA), and from 0 wt. to 20 wt. % itaconic acid, on the basis of the total weight of the acrylic material.

[0090] CR 9-101 is an isocyanate co-reactant, commercially available from Dow Inc. (Midland, MI).

[0091] For the following examples, a variety of coated and uncoated polymeric sheets were prepared. Sheets of 1 mil to 7 mil thickness were produced by cast extrusion and sheets of 8 mil to 10 mil thickness were produced by compression molding. The presence or absence of coatings is noted in the tables below.

[0092] Example 1

[0093] Each of the films was tested for Gardner clarity (ASTM D1746), haze (ASTM D1003), and impact resistance (ASTM D3420). 92 gauge polyethylene terephthalate (PET) was included as a comparative example. Results are shown in Table 1.Table 1 j [

[0094] As can be seen from Table 1, the polymeric sheets PS-1 to PS-4 generally have improved haze, Gardner clarity, and impact resistance, relative to the PET sheet.

[0095] Example 2

[0096] Four polymeric sheets of four grades of neutralized ethylene acid copolymer materials (PS-1 to PS-4) and comparative sheets of polyethylene terephthalate (PET) were coated with acrylic materials. The polymeric sheets were made using compression molding process. The resin was placed in a heated open mold cavity, the mold was then closed under pressure (using a hydraulic press), causing the material to flow and completely fdl the cavity, then pressure was held until the material solidified.

[0097] The polymeric sheets of PS-1, PS-2, PS-3, and PS-4 were 0.2 mm thick.

[0098] The polymeric sheets were coated with the acrylic materials. The polymeric sheets of PS-1 to PS-4 were treated with Corona discharge before coating. The PET fdms were not corona treated first set of experiments. Specifically, the polymeric sheets were coated with COATING- 1, COATING-2, and COATING-1 / CR 9-101 (100:7 mix ratio) via aMeyer rod drawdown coating method. After coating the polymeric sheets with the wet coating, samples were placed within an oven at 70 °C for 3 min to remove volatiles. The coating weights of the dried coatings were measured to be 3.6 Ib / ream for COATING-1 / CR 9-101 and 2.98 Ib / ream (3000 square feet) for COATING-2. The dried samples were removed from the oven, allowed to reach room temperature, and cured at 77 °F, 50% relative humidity before testing.

[0099] Samples hardness was measured using ASTM D3363-20 test method by pencil with results shown in Table 2. Pencil hardness goes from 6B (softest), 5B, 5B, 3B, 2B, B, HB, F, H, 2H, 3H, 4H, 5H, 6H, 7H, 8H, to 9H (hardest).Table 2

[0100] As can be seen from Table 2, the best results in terms of hardness were obtained with PS-1 and PS-4 that had been coated with either COATING-1 / CR 9-101 or COATING-2.

[0101] The coated and uncoated PS-1 samples were tested for haze, clarity, dart and abrasion. Comparative examples were also prepared using 92 ga PET. The PS-1 samples had a standard thickness of 8 mil (0.232 mm). The PET samples had a standard thickness of 1 mil (0.0254 mm). Thickness Ti is the measured thickness for the haze, Gardner clarity, and dart measurements. Thickness T2 is the measured thickness for the Zebedee clarity and Taber abrasion measurements.

[0102] Results are shown in Table 3.Table 3

[0103] Haze was measured using ASTM DI 003 Standard Test Method for Haze and Euminous Transmittance of Transparent Plastics. As can be seen from Table 3, the COATING-2 coating results in minimum impact on haze on PS-4 fdm and it even decreased the haze of the PET fdm. On the other hand, samples coated with COATING- 1 showed an increase in haze - 2.7X to 3.5Xthan uncoated samples. In every case, the haze of PET specimens as higher than the haze of PS- 1.

[0104] Clarity was measured, using ASTM D1746 - Standard Test Method for Transparency of Plastic Sheeting using Gardner and Zebedee meters. This test method covers the measurement of the transparency of plastic sheeting in terms of regular transmittance. As can be seen from Table 3, the clarity results with the Gardner and Zebedee meters match results from haze, where coating of COATING-2 improved the clarity of the PET fdm and maintained or slightly improved the clarity of PS-4 fdm, and coating with COATING- 1 / CR 9-101 decreased clarity between 3.5 and 4.3%.

[0105] In addition to optical properties, the two most-important mechanical properties for the application were measured. Specifically, impact resistance and abrasion resistance. Impact resistance was measured using ASTM D3420 method “Pendulum Impact Resistance of Plastic Film” and abrasion resistance was measured using ASTM D4060 method “Abrasion resistance of Organic Coatings by Taber Abraser”. As can be seen from Table 3, again the polymeric sheets comprising a neutralized ethylene acid copolymer material had the best abrasion and impact resistance.

[0106] While particular embodiments of the present invention have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. It is therefore intended to cover in the appended claims all such changes and modifications that are within the scope of this invention.

Claims

CLAIMS1. An article comprising: a polymeric sheet comprising a first surface and a second surface opposite the first surface, the polymeric sheet comprising a neutralized ethylene acid copolymer material comprising carboxylic acid groups, wherein the carboxylic acid groups of the ethylene acid copolymer are at least partially neutralized with metallic ions; and a coating in direct contact with at least a portion of the first surface of the polymeric sheet, the coating comprising an acrylic material, wherein the coating is an air-contacting layer.

2. The article of any preceding claim, wherein the combination of the polymeric sheet and the coating comprise at least 95% of a thickness of the article.

3. The article of any preceding claim, wherein the polymeric sheet has a thickness measured as a distance between the first surface and the second surface, and the thickness is from 0.01 mm to 0.51 mm.

4. The article of claim 3, wherein the ratio of a surface area of the first surface to a thickness of the article is at least 100,000 mm.

5. The article of any preceding claim, wherein the coating has a thickness of from 2 pm to 8 pm.

6. The article of any preceding claim, further comprising an adhesive layer in direct contact with the second surface of the polymeric sheet.

7. The article of any preceding claim, wherein the neutralized ethylene acid copolymer material comprises from 1 wt. % to 35 wt. % of a comonomer comprising carbon monoxide, sulfur dioxide, acrylonitrile, maleic anhydride, maleic acid diesters, maleic acid, maleic acid monoesters, itaconic acid, fumaric acid, fumaric acid monoester, a salt of these acids, glycidyl acrylate, glycidyl methacrylate, and glycidyl vinyl ether, methyl acrylate, ethyl acrylate, isopropyl acrylate, butyl acrylate, pentyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate and butyl methacrylate, pentyl methacrylate, or combinations thereof.

8. The article of any preceding claim, wherein the neutralized ethylene acid copolymer material is an ethylene methacrylic acid copolymer in which methacrylic acid groups of the copolymer are at least partially neutralized with sodium ions.

9. The article of any preceding claim, wherein the neutralized ethylene acid copolymer material comprises from 15% to 30% by weight copolymerized units of acrylic acid or methacrylic acid, and 70% to 85% by weight copolymerized units of ethylene, based on the total weight of the neutralized acid copolymer; and about 40% to about 70% of carboxylic acid groups of the neutralized acid copolymer are neutralized as carboxylic acid salts comprising sodium cations.

10. The article of any preceding claim, wherein the neutralized ethylene acid copolymer material has a melt flow index (h) of from 0.9 g / 10 min to 13 g / 10 min, as measured by ASTM D1238.

11. The article of any preceding claim, wherein the acrylic material comprises from 20 wt. % to 80 wt. % of ethyl acrylate (EA), from 15 wt. % to 75 wt. % methyl methacrylate (MMA),from 0 wt. % to 20 wt. % of hydroxyl-ethyl methacrylate (HEMA), and from 0 wt. to 20 wt. % itaconic acid; on the basis of the total weight of the acrylic material.

12. The article of any preceding claim, wherein the acrylic material comprises from 10 wt. % to 80 wt. % of butyl acrylate (BA), from 15 wt. % to 75 wt. % methyl methacrylate (MMA), from 0 wt. % to 20 wt. % of hydroxyl-ethyl methacrylate (HEMA), from 0 wt. to 20 wt. % styrene; and from 1 wt. % to 20 wt. % of a polyisocyanate, on the basis of the total weight of the acrylic material.

13. The article of any preceding claim, wherein the article is a screen protector.

14. A coated substrate comprising: a transparent substrate; and an article positioned on at least a portion of a first surface of the substrate, the article comprising: a polymeric sheet comprising a first surface and a second surface opposite the first surface, the polymeric sheet comprising a neutralized ethylene acid copolymer material comprising carboxylic acid groups, wherein the carboxylic acid groups of the ethylene acid copolymer are at least partially neutralized with metallic ions; and a coating in direct contact with at least a portion of the first surface of the polymeric sheet, the coating comprising an acrylic material, wherein the coating is an air-contacting layer.

15. The coated substrate of claim 14, wherein the substrate comprises glass.

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