CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of priority under 35 U.S.C. § 119 of U.S. Provisional Application Serial No. 63/320269 filed on March 16, 2022, the content of which is relied upon and incorporated herein by reference in its entirety.

Field

[0002] The present disclosure relates generally to paper interleafs and methods and apparatuses for packing glass sheets with the same.

Background

[0003] In the packing and transportation of glass sheets, such as glass sheets used for display applications, an interleaf material, such as an interleaf paper, is commonly interposed between glass sheets in order to help protect the sheets from damage. In addition to imparting physical protection, interleaf materials are also designed to minimize the transfer of contaminants onto the glass surface. In addition, such interleaf materials should not impart undesirable levels of electrostatic charge to the glass or undesirably adhere to the glass surface. Moreover, such materials should perform well over time in a variety of different environments, such as in varying temperature and/or humidity conditions. There is a continued need for interleaf materials to meet these and other requirements in a cost effective manner.

SUMMARY

[0004] Embodiments disclosed herein include a paper interleaf. The paper interleaf includes a base paper substrate that includes at least one of a lignin or a polysaccharide. The paper interleaf also includes a coating adhered to the base paper substrate that includes at least about 0.5 weight percent starch.

[0005] Embodiments disclosed herein also include a method of making an paper interleaf. The method includes applying a coating solution to a base paper substrate. The base paper substrate includes at least one of a lignin or a polysaccharide. The coating solution includes at least 0.5 about weight percent starch, at least one of an alcohol, a polyol, or an amine, and water. [0006] Embodiments disclosed herein also include a method of packing glass sheets. The method includes positioning two or more glass sheets in a packing apparatus. The method also includes disposing a paper interleaf between adjacent glass sheets of the two or more glass sheets. The paper interleaf includes a base paper substrate that includes at least one of a lignin or a polysaccharide. The paper interleaf also includes a coating adhered to the base paper substrate that includes at least about 0.5 weight percent starch.

[0007] Additional features and advantages of the embodiments disclosed herein will be set forth in the detailed description which follows, and in part will be readily apparent to those skilled in the art from that description or recognized by practicing the disclosed embodiments as described herein, including the detailed description which follows, the claims, as well as the appended drawings.

[0008] It is to be understood that both the foregoing general description and the following detailed description present embodiments intended to provide an overview or framework for understanding the nature and character of the claimed embodiments. The accompanying drawings are included to provide further understanding and are incorporated into and constitute a part of this specification. The drawings illustrate various embodiments of the disclosure, and together with the description serve to explain the principles and operations thereof.

BRIEF DESCRIPTION OF THE DRAWINGS

[0009] FIG. 1 is a side perspective view of an exemplary packing apparatus in accordance with embodiments disclosed herein;

[0010] FIG. 2 is a side perspective view of a plurality of glass sheets and paper interleafs disposed between adjacent glass sheets in an exemplary packing apparatus in accordance with embodiments disclosed herein;

[0011] FIG. 3 is perspective view of an exemplary glass sheet in accordance with embodiments disclosed herein;

[0012] FIG. 4 is a perspective view of an exemplary paper interleaf in accordance with embodiments disclosed herein;

[0013] FIG. 5 is a side cutaway view of exemplary application of a coating solution onto a base paper substrate in accordance with embodiments disclosed herein; [0014] FIG. 6 is a side cutaway view of an exemplary paper interleaf comprising a base paper substrate and a coating adhered to its opposing major surfaces in accordance with embodiments disclosed herein;

[0015] FIG. 7 is a chart showing viscosity of exemplary coating solutions in accordance with embodiments disclosed herein;

[0016] FIG. 8 is a chart showing percent elongation at break of exemplary coating layer films in accordance with embodiments disclosed herein;

[0017] FIGS. 9A-9C are charts showing water contact angles of glass sheets under various conditions as disclosed herein; and

[0018] FIG. 10 is a chart showing particle densities on glass sheets under various conditions as disclosed herein.

DETAILED DESCRIPTION

[0019] Reference will now be made in detail to the present preferred embodiments of the present disclosure, examples 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 like parts. However, this disclosure may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

[0020] Ranges can be expressed herein as from “about” one particular value, and/or to “about” another particular value. When such a range is expressed, another embodiment includes from the one particular value and/or to the other particular value. Similarly, when values are expressed as approximations, for example by use of the antecedent “about,” it will be understood that the particular value forms another embodiment. It will be further understood that the endpoints of each of the ranges are significant both in relation to the other endpoint, and independently of the other endpoint.

[0021] Directional terms as used herein - for example up, down, right, left, front, back, top, bottom - are made only with reference to the figures as drawn and are not intended to imply absolute orientation.

[0022] Unless otherwise expressly stated, it is in no way intended that any method set forth herein be construed as requiring that its steps be performed in a specific order, nor that with any apparatus specific orientations be required. Accordingly, where a method claim does not actually recite an order to be followed by its steps, or that any apparatus claim does not actually recite an order or orientation to individual components, or it is not otherwise specifically stated in the claims or description that the steps are to be limited to a specific order, or that a specific order or orientation to components of an apparatus is not recited, it is in no way intended that an order or orientation be inferred, in any respect. This holds for any possible non-express basis for interpretation, including: matters of logic with respect to arrangement of steps, operational flow, order of components, or orientation of components; plain meaning derived from grammatical organization or punctuation, and; the number or type of embodiments described in the specification.

[0023] As used herein, the singular forms "a," "an" and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to “a” component includes aspects having two or more such components, unless the context clearly indicates otherwise.

[0024] As used herein, the term lignin refers to a crosslinked phenolic biopolymer having a weight average molecular weight of at least about 5,000 grams per mole.

[0025] As used herein, the term polysaccharide refers to a polymeric carbohydrate having monosaccharide units bound by glyosidic linkages. Examples include cellulose, amylose, glucan, xylan, mannan, arabinan, and galactan.

[0026] As used herein, the term starch refers to a polysaccharide comprising glucose monomers joined in alpha 1, 4 linkages, which may be branched and/or linear. An exemplary linear starch is amylose. An exemplary branched starch is amylopectin.

[0027] As used herein, the term “percent elongation at break” refers to percent elongation at break of coating layer films in accordance with the Percent Elongation at Break Procedure described herein.

[0028] As used herein, the term “water contact angle” refers to the water contact angle of a glass sheet contacted with interleaf paper in accordance with the Water Contact Angle Procedure described herein.

[0029] As used herein, the term “surface particle density” refers to the density of particles on a surface of a glass sheet contacted with interleaf paper in accordance with the Surface Particle Density Procedure described herein.

[0030] FIG. 1 shows a side perspective view of an exemplary packing apparatus 100 in accordance with embodiments disclosed herein. Packing apparatus 100 includes cover 102, support member 104, seat 106, pallet 108, and at least one support post 110. Packing apparatus 100 is configured to enclose a plurality of glass sheets positioned therein.

[0031] In certain exemplary embodiments, cover 102 can comprise a metal, a polymer, a polymer composite, and or metal/polymer laminate. In certain exemplary embodiments, support member 104, seat 106, pallet 108, and /or support post 110 can comprise a metal, such as aluminum or stainless steel, or a polymer composite.

[0032] FIG. 2 shows a side perspective view of a plurality of glass sheets 10 and paper interleafs 20 disposed between adjacent glass sheets 10 in an exemplary packing apparatus 100 in accordance with embodiments disclosed herein. Glass sheets 10 and paper interleafs 20 are positioned on cushioning member 112, which is in turn positioned over seat 106, wherein cushioning member 112 may be adhered to seat 106 with a suitable adhesive. Cushioning member 112 may, for example, comprise a resilient polymeric material, such as a material comprising ethylene-propylene-diene terpolymer.

[0033] FIG. 3 shows a perspective view of an exemplary glass sheet 10 in accordance with embodiments disclosed herein. Glass sheet 10 has a first major surface 12, an opposing second major surface 14 extending in a generally parallel direction to the first major surface 12 (on the opposite side of the glass sheet 10 as the first major surface 12) and an edge surface 16 extending between the first major surface 12 and the second major surface 14 and extending in a generally perpendicular direction to the first and second major surfaces 12, 14. [0034] Glass sheet 10 may comprise a variety of glass compositions. For example, embodiments disclosed herein include those in which glass sheet 10 comprises an alkali free glass composition, comprising 58-65 weight percent (wt%) SiO2, 14-20wt% AI2O3, 8-12wt% B2O3, l-3wt% MgO, 5-10wt% CaO, and 0.5-2wt% SrO. Glass sheet 10 may also comprise an alkali free glass composition, comprising 58-65wt% SiO2, 16-22wt% AI2O3, l-5wt% B2O3, l-4wt% MgO, 2-6wt% CaO, l-4wt% SrO, and 5-10wt% BaO. In addition, glass sheet 10 may comprise an alkali free glass composition, comprising 57-61wt% SiO2, 17-21wt% AI2O3, 5-8wt% B2O3, l-5wt% MgO, 3-9wt% CaO, 0-6wt% SrO, and 0-7wt% BaO. Glass sheet 10 may also comprise an alkali containing glass composition, comprising 55-72wt% SiO2, 12-24wt% AI2O3, 10-18wt% Na2O, 0-10wt% B2O3, 0-5 wt% K2O, 0-5 wt% MgO, and 0- 5wt% CaO, which, in certain embodiments, may also comprise 1 -5wt% K2O and 1 -5wt% MgO.

[0035] In certain exemplary embodiments, glass sheet 10 has a thickness of less than about 1 millimeter, such as a thickness ranging from about 0.1 millimeters to about 1 millimeter, including from about 0.2 millimeters to about 0.8 millimeters, and further including from about 0.3 millimeters to about 0.7 millimeters, including about 0.5 millimeters.

[0036] FIG. 4 shows a perspective view of an exemplary paper interleaf 20 in accordance with embodiments disclosed herein. Paper interleaf 20 has a first major surface 22 and an opposing second major surface 24 extending in a generally parallel direction to the first major surface 22 (on the opposite side of the paper interleaf 20 as the first major surface 22).

[0037] FIG. 5 shows a side cutaway view of exemplary application of a coating solution 200 onto a base paper substrate 100 in accordance with embodiments disclosed herein. As shown in FIG. 5, coating solution 200 is applied to base paper substrate 100 with a thin film applicator, specifically a blade applicator 300. Blade applicator 300 can extend slightly above a major surface of base paper substrate 100 while moving in a movement direction (shown in FIG. 5 by arrow “M”) in order to apply a thin coating solution 200 with relatively uniform thickness onto the major surface of base paper substrate 100. Exemplary blade applicators 300 include blade casting machines available from Kejing Group Company.

[0038] Once coating solution 200 has been applied to base paper substrate 100, it can be dried in order to evaporate solvents from coating solution 200. Drying of coating solution 200 may be accomplished by methods known to persons having ordinary skill in the art, including convective, conductive, and radiative methods. Drying temperatures may, for example, range from about 40°C to about 100°C, such as from about 60°C to about 90°C. Drying times may, for example, range from about 1 minute to about 30 minutes, such as from about 5 minutes to about 10 minutes.

[0039] Application (as shown, for example, in FIG. 5) and drying of coating solution 200 on base paper substrate 100 can be repeated on opposing major surface of base paper substrate 100 in order to form a paper interleaf with coating adhered to its opposing major surfaces. FIG. 6 shows a side cutaway view of an exemplary paper interleaf 20 comprising a base paper substrate 100 and a coating 210 adhered to its opposing major surfaces.

[0040] In certain exemplary embodiments, coating 210 comprises at least about 0.5 weight percent starch, such as at least about 3 weight percent starch, and further such as at least about 10 weight percent starch, and yet further such as at least about 20 weight percent starch, and still yet further such as at least about 50 weight percent starch, such as from about 0.5 weight percent starch to about 99 weight percent starch, including from about 3 weight percent starch to about 98 weight percent starch, and further including from about 50 weight percent starch to about 97 weight percent starch.

[0041] In certain exemplary embodiments, starch may comprise a plant-based starch, such as com starch, potato starch, rice starch, or pea starch. Starch may be nonionic, cationic, or anionic. Starch may be linear and/or branched.

[0042] In certain exemplary embodiments, coating solution 200 comprises at least about 0.5 weight percent starch, such as at least about 3 weight percent starch, and further such as at least about 10 weight percent starch, and yet further such as at least about 20 weight percent starch, such as from about 0.5 weight percent starch to about 50 weight percent starch, including from about 3 weight percent starch to about 40 weight percent starch, and further including from about 10 weight percent starch to about 30 weight percent starch.

[0043] In certain exemplary embodiments, coating solution 200 comprises water and at least one of an alcohol, a polyol, or an amine. In certain exemplary embodiments, coating solution 200 comprises an alcohol. In certain exemplary embodiments, coating solution 200 comprises a polyol. In certain exemplary embodiments, coating solution 200 comprises an amine. In certain exemplary embodiments, coating solution 200 comprises an alcohol and a polyol. In certain exemplary embodiments, coating solution 200 comprise an alcohol and an amine. In certain exemplary embodiments, coating solution 200 comprises a polyol and an amine. In certain exemplary embodiments, coating solution 200 comprises an alcohol, a polyol, and an amine. In certain exemplary embodiments, coating solution 200 comprises water, an alcohol, a polyol, and a amine.

[0044] In certain exemplary embodiments, alcohol may be selected from at least one of glycerol, xylitol, or sorbitol. In certain exemplary embodiments, polyol may comprise polyvinyl alcohol (PVA). In certain exemplary embodiments, amine may comprise one or more compounds having the general structure: wherein R is a C3-C10 cyclic compound, R’ is a C1-C3 aliphatic compound, and n ranges from 1 to 5, such as from 2 to 4. In certain exemplary embodiments, amine may be selected from at least one of hexamethoxymethylmelamine (HMMM), hexamethylomelamine, and diethylaminoethanol.

[0045] In certain exemplary embodiments, base paper substrate 100 comprises at least one of a lignin or a polysaccharide. In certain exemplary embodiments, base paper substrate 100 comprises a lignin and a polysaccharide.

[0046] In certain exemplary embodiments, base paper substrate 100 comprises a total lignin content of at least about 5 weight percent, such as at least about 10 weight percent, and further such as at least about 15 weight percent, and yet further such as at least about 20 weight percent, including from about 5 weight percent to about 40 weight percent, and further including from about 10 weight percent to about 35 weight percent, and yet further including from about 20 weight percent to about 30 weight percent.

[0047] In certain exemplary embodiments, base paper substrate 100 comprises a total polysaccharide content of no more than about 80 weight percent, such as no more than about 75 weight percent, and further such as no more than about 70 weight percent, and yet further such as no more than about 65 weight percent, including from about 40 weight percent to about 80 weight percent, and further including from about 45 weight percent to about 75 weight percent, and yet further including from about 50 weight percent to about 70 weight percent.

[0048] In certain exemplary embodiments, base paper substrate 100 comprises a thickness of from about 20 microns to about 200 microns, such as from about 50 microns to about 100 microns, and coating 210 comprises a thickness of from about 0.05 microns to about 5 microns, such as from about 0.1 micron to about 2 microns, and further such as from about 0.2 microns to about 1 micron.

[0049] In certain exemplary embodiments, coating solution 200 is made by forming a starch solution by mixing starch and solution comprising water and then forming coating solution 200 by mixing the starch solution with a solution comprising at least one of an alcohol or a polyol. During the mixing of starch and the solution comprising water in order to form a starch solution and/or during the mixing of the starch solution with a solution comprising at least one of an alcohol or a polyol, the temperature can be at least about 75°C, such at least about 90°C, including from about 75°C to about 100°C, and further including from about 90°C to about 100°C. Mixing time of the solutions may, for example, range from about 10 minutes to about 3 hours, such as from about 30 minutes to about 2 hours and can accomplished by stirring devices known to persons having ordinary skill in the art, such as magnetic stirrers.

[0050] In certain exemplary embodiments, solution comprising water also comprises an amine, such as HMMM, wherein the amine is dissolved in water prior to mixing the solution comprising water with starch, such that starch solution comprises water, starch, and an amine. In certain exemplary embodiments, solution comprising at least one of an alcohol or a polyol comprises water and a polyol, such as PVA, which is mixed with water, for example, at a temperature of at least about 75°C, such at least about 90°C, including from about 75°C to about 100°C, and further including from about 90°C to about 100°C and at a time from about 10 minutes to about 3 hours, such as from about 30 minutes to about 2 hours. In certain exemplary embodiments, solution comprising at least one of an alcohol or a polyol comprises an alcohol, such as glycerol. In certain exemplary embodiments, solution comprising water and a polyol are mixed with starch solution. In certain exemplary embodiments, solution comprising alcohol is mixed with starch solution. In certain exemplary embodiments, solution comprising water and a polyol and solution comprising an alcohol are mixed with starch solution.

[0051] In certain exemplary embodiments, alcohol, such as glycerol, acts as a plasticizer which can improve the flexibility of coating 210. Such can, for example, mitigate cracking of coating 210 during transportation (e.g., as a result of vibration).

[0052] In certain exemplary embodiments, amine, such as HMMM, acts as a crosslinking agent between starch and polyol, such as PVA. Such can, for example, improve the stability and homogeneity of coating 210.

[0053] In certain exemplary embodiments, coating 210 is substantially free of silicone.

[0054] Examples

[0055] Embodiments disclosed herein are further illustrated by the following non-limiting examples.

[0056] Five exemplary coating solutions were prepared from components that included one or more of aqueous starch solutions, aqueous PVA solutions, glycerol, and/or HMMM. The aqueous starch solutions included 10 weight percent grade com powder available from Shanghai Aladdin Biochemical Technology Co., Ltd. and/or 27 weight percent starch Vector 1C27216 solution available from Roquette Co. The aqueous PVA solution comprised 10 weight percent PVA available from Sinopharm Group Co. The glycerol was an electrophoresis-grade reagent available from Shanghai Aladdin Biochemical Technology Co., Ltd. The balance of the aqueous solutions comprised deionized water.

[0057] Specifically, in the case of the aqueous com starch solutions, corn starch powder was mixed with deionized water and then heated to about 95°C for about 30 minutes with continuous mixing. In the case of the aqueous PVA solutions, PVA was mixed with deionized water and heated to about 95°C for about 2 hours with continuous mixing. For Example 1 , aqueous com starch solution and aqueous PVA solution were then mixed for about 30 minutes. For Example 2, only Vector starch solution was used. For Example 3, aqueous com starch solution, aqueous PVA solution, and glycerol were mixed for about 1 hour. For Example 4, Vector starch solution, aqueous PVA solution, and glycerol were mixed for about 1 hour. For Example 5, HMMM was dissolved in deionized water before mixing with com starch powder. Then the mixture was heated to about 95°C for about 30 minutes, which was then mixed with aqueous PVA solution for about 30 minutes. All heating operations were done in an oil bath and all mixing operations were conducted with magnetic bar stirring at about 500 rpm. The Example 1-5 coating solution compositions are set forth in Table 1.

[0058] Table 1 :

[0059] Each exemplary coating solution was cooled to room temperature and then applied to a base paper at room temperature (about 25°C). The base paper was NVA newsprint paper available from Alberta Newsprint having a basis weight of about 45 grams per square meter. The application process was carried out by using a blade-casting machine with heating function available from Kejing Group Company. Aluminum foil was secured on the machine via a vacuum force and the base paper was stacked on the aluminum foil with one edge of the paper mechanically fixed at a casting start point. A 180 millimeter width blade was used to apply the coating solution to the base paper. The height of the blade above the paper was fixed at about 15 microns and the blade casting speed was fixed at about 180 millimeters per minute. Once coating solution had been applied over a major surface of the base paper, the paper was transferred onto a plate with two opposing edges fixed by clamps, which was, in turn, placed into a pre-heated blade casting machine at a temperature of about 80°C. The coating composition was then subsequently dried at a temperature of about 80°C for a time of about 7 minutes in order to form a coating over a first major surface of the base paper. This entire process was repeated in order to form a second coating over the opposing major surface of the base paper. After coating, the paper was then cut into about 4 inch by 4 inch samples for testing.

[0060] Coating Solution Viscosity

[0061] Viscosity of some of the above exemplary coating solutions was tested to determine applicability for coating over paper. Specifically, the Example 2 coating solution was measured by a Kinexus Pro+ Rheometer and the Example 3 and 4 coating solutions were measured by Brookfield RV111 with the results shown in FIG. 7. [0062] Eight additional exemplary coating solutions were prepared in accordance with methods described above and set forth in Table 2.

[0063] Table 2:

[0064] Percent Elongation at Break Procedure

[0065] The following Percent Elongation at Break Procedure was conducted to evaluate the flexibility of exemplary coating layer films. Each coating solution of Examples 6-13 was poured into a Petri dish and stored in a vacuum oven for about 1 hour at about 25°C. Each Petri dish was then moved to a fan oven for drying at about 8 hours at about 60°C. Each coating layer film was then peeled off the Petri dish. Each coating layer film was then cut in accordance with ISO 1184 (Plastics-D eformation of tensile properties of films) with percent elongation at break measured by Instron equipment and the results shown in FIG. 8. As can be seen in FIG. 8, one or more exemplary coatings, specifically Examples 7-12, showed a percent elongation at break of at least about 40%, such as at least about 100% (Examples 7- 11), and further such as at least about 150% (Examples 7-10), and yet further such as at least about 200% (Example 10), including from about 40% to about 300%, such as from about 100% to about 250%.

[0066] Surface morphology of exemplary coatings on base paper were also compared to the uncoated base paper (NVA newsprint as described above) by viewing high resolution scanning electron microscope (SEM) images of the various coated and uncoated papers. While relatively high roughness and porousness were characteristic of uncoated base paper surfaces, the exemplary coated papers exhibited a generally flatter and smoother surface as compared to the uncoated paper.

[0067] Due to penetration of coating material into the fiber structure of the base paper, the overall thickness of exemplary coated papers was not significantly greater than the thickness of uncoated paper, which facilitates dense packing of glass sheets and minimizes transportation cost. Thickness of exemplary coatings was taken an average of multiple SEM measurements and coated paper total thickness was measured from an average of cross section SEM images. Coating layer thickness and total coated paper thickness increased as a function of starch concentration of the coating solution. Coating weight was measured for exemplary coated papers and base paper, wherein both were stored at similar humidity for more than 1 day before weighting. Thicknesses and weights of exemplary coatings as well as total thickness of exemplary coated papers are set forth in Table 3.

[0068] Table 3

[0069] Glass Washing Procedures

[0070] A first glass washing procedure was conducted by first washing samples of Coming® Eagle XG® glass having a major surface area of about four inches by four inches and a thickness of about 0.5 millimeters in an aqueous solution containing about 4 weight percent of Semiclean KG detergent (produced by Yokohama Oils & Fats Industry Co., Ltd.) at a temperature of about 71°C for about 12 minutes with ultrasonic vibration of about 36 kHz. Next, the samples were washed in deionized water at a temperature of about 71°C for about 12 minutes with ultrasonic vibration of about 36 kHz, rinsed in deionized water at a temperature of about 54°C for about 5 minutes, soaked in deionized water at a temperature of about 35°C for about 8 minutes, and then rinsed in deionized water at a temperature of about 25°C for about 5 minutes. Then the samples were dried in a vacuum oven at a temperature of about 50°C for about 30 minutes.

[0071] A second glass washing procedure was conducted by first washing samples of Coming® Eagle XG® glass having a major surface area of about four inches by four inches and a thickness of about 0.5 millimeters in an aqueous solution containing about 1 weight percent of Semiclean KG detergent at a temperature of about 50°C for about 1 minute with ultrasonic vibration of about 36 kHz. Next, the samples were washed in deionized water at a temperature of about 50°C for about 1 minute with ultrasonic vibration of about 36 kHz and then rinsed in deionized water at a temperature of about 25°C for about 5 minutes. Then the samples were dried in a vacuum oven at a temperature of about 50°C for about 30 minutes. [0072] Water Contact Angle Procedure

[0073] Ten samples of Coming® Eagle XG® glass having a major surface area of about four inches by four inches and a thickness of about 0.5 millimeters and washed according to the first glass washing procedure described above were stacked between various paper interleafs while being packaged with an ultra-high vacuum aluminum foil. The package was then stored in a constant temperature humidity chamber at about 25°C and about 74% relative humidity while under about 5 kilograms of weight to simulate dense packing behaviors. After 2 weeks and 8 weeks, the samples were unpacked and surface water contact angles were measured on a major surface by measuring the angle that about a 2 microliter droplet of water makes with the glass surface as determined by the Kruss DSA 100E Drop Shape Analyzer prior to and subsequent to being washing by either the first or second glass washing procedures described above.

[0074] Measured glass water contact angles for glass samples under various conditions are shown in FIGS. 9A-9C wherein the letters A-X along the X-axis of the tables correspond as follows: A = sample washed with first procedure and not stacked between paper; B = sample stacked for 2 weeks with NVA newsprint base paper interleaf; C = sample stacked for 2 weeks with Example 1 interleaf; D = sample stacked for 2 weeks with Example 2 interleaf; E = sample stacked for 2 weeks with Example 3 interleaf; F = sample stacked for 2 weeks with Example 4 interleaf; G = sample stacked for 2 weeks with NVA newsprint base paper interleaf and subsequently washed with first procedure; H = sample stacked for 2 weeks with Example 1 interleaf and subsequently washed with first procedure; 1 = sample stacked for 2 weeks with Example 2 interleaf and subsequently washed with first procedure; J = sample stacked for 2 weeks with Example 3 interleaf and subsequently washed with first procedure; K = sample stacked for 2 weeks with Example 4 interleaf and subsequently washed with first procedure; L = sample stacked for 8 weeks with NVA newsprint base paper interleaf; M = sample stacked for 8 weeks with Example 1 interleaf; N = sample stacked for 8 weeks with Example 2 interleaf; O = sample stacked for 8 weeks with Example 3 interleaf; P = sample stacked for 8 weeks with Example 4 interleaf; Q = sample stacked for 8 weeks with NVA newsprint base paper interleaf and subsequently washed with first procedure; R = sample stacked for 8 weeks with Example 1 interleaf and subsequently washed with first procedure; S = sample stacked for 8 weeks with Example 2 interleaf and subsequently washed with first procedure; T = sample stacked for 8 weeks with Example 3 interleaf and subsequently washed with first procedure; U = sample stacked for 8 weeks with Example 4 interleaf and subsequently washed with first procedure; V = sample stacked for 8 weeks with Example 3 interleaf; W = sample stacked for 8 weeks with Example 3 interleaf and subsequently washed with first procedure; and X = sample stacked for 8 weeks with Example 3 interleaf and subsequently washed with second procedure.

[0075] As can be seen from FIGS. 9A-9C, samples of glass sheets contacted with exemplary paper interleafs (e.g., Examples 1-4) in accordance with the Water Contact Angle Procedure (with subsequent washing) have a water contact angle of less than about 5 degrees, such as a water contact angle of less than about 3 degrees, including a water contact angle of from about 0 degrees to about 5 degrees, such as a water contact angle of from about 1 degree to about 3 degrees.

[0076] Surface Particle Density Procedure

[0077] Samples of Coming® Eagle XG® glass having a major surface area of about four inches by four inches and a thickness of about 0.5 millimeters and washed according to the first glass washing procedure were stacked between various paper interleafs. The paper interleafs included NVA base paper, polysaccharide based paper (PBP) (available from Tokushu, Japan), and the paper interleafs of Examples 1-4. To simulate transportation of packaged glass, the stacks of glass sheets and paper interleafs were subjected to a mimic dense packing (MDP) procedure wherein they were vibrated using Telecordia Standard (GR63 Transportation Vibration, Section 4.4.5). Following vibration, the samples were washed according to the second glass washing procedure. Following washing, particle counts on a major surface of each sample were measured using a Toray HS830 system. Analyzed particle size ranges included: small particles (having a diameter ranging from about 0.3 microns to about 0.5 microns); medium particles (having a diameter ranging from about 0.5 microns to about 1 micron); and large particles (having a diameter of at least about 1 micron). Particle densities on glass sheet samples subjected to the MDP procedure between various paper interleafs are shown in FIG. 10.

[0078] As can be seen from FIG. 10, samples of glass sheets contacted with exemplary paper interleafs (e.g., Examples 1-4) in accordance with the Surface Particle Density Procedure (with subsequent washing) have a surface particle density of less than about 80 particles per square centimeter, such as less than about 60 particles per square centimeter, and further such as less than about 40 particles per square centimeter, including from about 2 particles per square centimeter to about 80 particles per square centimeter, such as from about 5 particles per square centimeter to about 60 particles per square centimeter, and further such as from about 10 particles per square centimeter to about 40 particles per square centimeter. [0079] Embodiments disclosed herein can enable cost effective packing and transportation of glass sheets, such as glass sheets used for display applications, having major surfaces with, for example, acceptable hydrophilicity and reduced particle densities.

[0080] It will be apparent to those skilled in the art that various modifications and variations can be made to embodiments of the present disclosure without departing from the spirit and scope of the disclosure. Thus, it is intended that the present disclosure cover such modifications and variations provided they come within the scope of the appended claims and their equivalents.